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Sample records for air electrode tube

  1. Experimental study of cylindrical air electrodes

    NASA Astrophysics Data System (ADS)

    Viitanen, M.; Lamminen, J.; Lampinen, M. J.

    1991-11-01

    The electrodes studied here are cylindrical and prepared to be placed inside the inner surface of a sintered brass tube, which is nickel-plated. Previously we have reported on the preparation of flat air electrodes and also on long run tests carried out with these electrodes. The electrode material was prepared by the so-called wet method to obtain a carbon dough which is easy to handle. The material preparation remains the same, but owing to the different geometrical shape, the preparation of the electrode itself is quite different. We have studied here the long-term performance of these new cylindrical air electrodes and at the same time measured the carbonate content of the electrolyte. We have also analyzed by comparative methods which property of the electrode lowers the performance after a fairly long period.

  2. Bifunctional oxygen/air electrodes

    NASA Astrophysics Data System (ADS)

    Jörissen, Ludwig

    A selective review on the materials and construction principles used for bifunctional oxygen/air electrodes is given. The discussion emphasizes the catalytically active materials used for the construction of these electrodes, which are a key component in electrically rechargeable air breathing electrochemical systems. Whereas, in acid electrolytes normally noble metal catalysts must be used, there is a possibility to use less expensive transition metal oxides in alkaline electrolytes. Typical transition metal oxides have the perovskite, pyrochlore and spinel structure.

  3. Applying a tapered electrode on a porous ceramic support tube by masking a band inside the tube and drawing in electrode material from the outside of the tube by suction

    DOEpatents

    Vasilow, Theodore R.; Zymboly, Gregory E.

    1991-01-01

    An electrode is deposited on a support by providing a porous ceramic support tube (10) having an open end (14) and closed end (16); masking at least one circumferential interior band (18 and 18') inside the tube; evacuating air from the tube by an evacuation system (30), to provide a permeability gradient between the masked part (18 and 18') and unmasked part (20) of the tube; applying a liquid dispersion of solid electrode particles to the outside surface of the support tube, where liquid flows through the wall, forming a uniform coating (42) over the unmasked support part (20) and a tapered coating over the masked part (18 and 18').

  4. Applying a tapered electrode on a porous ceramic support tube by masking a band inside the tube and drawing in electrode material from the outside of the tube by suction

    DOEpatents

    Vasilow, T.R.; Zymboly, G.E.

    1991-12-17

    An electrode is deposited on a support by providing a porous ceramic support tube having an open end and closed end; masking at least one circumferential interior band inside the tube; evacuating air from the tube by an evacuation system, to provide a permeability gradient between the masked part and unmasked part of the tube; applying a liquid dispersion of solid electrode particles to the outside surface of the support tube, where liquid flows through the wall, forming a uniform coating over the unmasked support part and a tapered coating over the masked part. 2 figures.

  5. Flexible intramuscular micro tube electrode combining electrical and chemical interface.

    PubMed

    Tian, Hong-Chang; Liu, Jing-Quan; Du, Jing-Cheng; Kang, Xiao-Yang; Zhang, Chuan; Yang, Bin; Chen, Xiang; Yang, Chun-Sheng

    2014-01-01

    With the rapidly developed micromachining technology, various kinds of sophisticated microelectrodes integrated with micro fluidic channels are design and fabricated for not only electrophysiological recording and stimulation, but also chemical drug delivery. As many efforts have been devoted to develop rigid microprobes for neural research of brain, few researchers concentrate on fabrication of flexible microelectrodes for intramuscular electrophysiology and chemical interfacing. Since crude wire electrodes still prevail in functional electrical stimulation (FES) and electromyography (EMG) recording of muscle, here we introduce a flexible micro tube electrode combining electrical and chemical pathway. The proposed micro tube electrode is manufactured based on polymer capillary, which provide circumferential electrode site contacting with electro-active tissue and is easy to manufactured with low cost.

  6. Air feed tube support system for a solid oxide fuel cell generator

    DOEpatents

    Doshi, Vinod B.; Ruka, Roswell J.; Hager, Charles A.

    2002-01-01

    A solid oxide fuel cell generator (12), containing tubular fuel cells (36) with interior air electrodes (18), where a supporting member (82) containing a plurality of holes (26) supports oxidant feed tubes (51), which pass from an oxidant plenum (52") into the center of the fuel cells, through the holes (26) in the supporting member (82), where a compliant gasket (86) around the top of the oxidant feed tubes and on top (28) of the supporting member (82) helps support the oxidant feed tubes and center them within the fuel cells, and loosen the tolerance for centering the air feed tubes.

  7. Air flow exploration of abrasive feed tube

    NASA Astrophysics Data System (ADS)

    Zhang, Shijin; Li, Xiaohong; Gu, Yilei

    2009-12-01

    An abrasive water-jet cutting process is one in which water pressure is raised to a very high pressure and forced through a very small orifice to form a very thin high speed jet beam. This thin jet beam is then directed through a chamber and then fed into a secondary nozzle, or mixing tube. During this process, a vacuum is generated in the chamber, and garnet abrasives and air are pulled into the chamber, through an abrasive feed tube, and mixes with this high speed stream of water. Because of the restrictions introduced by the abrasive feed tube geometry, a vacuum gradient is generated along the tube. Although this phenomenon has been recognized and utilized as a way to monitor nozzle condition and abrasive flowing conditions, yet, until now, conditions inside the abrasive feed line have not been completely understood. A possible reason is that conditions inside the abrasive feed line are complicated. Not only compressible flow but also multi-phase, multi-component flow has been involved in inside of abrasive feed tube. This paper explored various aspects of the vacuum creation process in both the mixing chamber and the abrasive feed tube. Based on an experimental exploration, an analytical framework is presented to allow theoretical calculations of vacuum conditions in the abrasive feed tube.

  8. Pressure Drop in Radiator Air Tubes

    NASA Technical Reports Server (NTRS)

    Parsons, S R

    1921-01-01

    This report describes a method for measuring the drop in static pressure of air flowing through a radiator and shows (1) a reason for the discrepancy noted by various observers between head resistance and drop in pressure; (2) a difference in degree of contraction of the jet in entering a circular cell and a square cell; (3) the ratio of internal frictional resistance to total head resistance for two representative types; (4) the effect of smoothness of surface on pressure gradient; and (5) the effects of supplying heat to the radiator on pressure gradient. The fact that the pressure gradients are found to be approximately proportional to the square of the rate of flow of air appears to indicate turbulent flow, even in the short tubes of the radiator. It was found that the drop in the static pressure in the air stream through a cellular radiator and the pressure gradient in the air tubes are practically proportional to the square of the air flow in a given air density; that the difference between the head resistance per unit area and the fall of static pressure through the air tubes in radiators is apparent rather than real; and that radiators of different types differ widely in the amount of contraction of the jet at entrance. The frictional resistance was found to vary considerably, and in one case to be two-thirds of the head resistance in the type using circular cells and one-half of the head resistance of the radiator type using square cells of approximately the same dimensions.

  9. Improved zinc electrode and rechargeable zinc-air battery

    SciTech Connect

    Ross, P.N. Jr.

    1988-06-21

    The invention comprises an improved rechargeable zinc-air cell/battery having recirculating alkaline electrolyte and a zinc electrode comprising a porous foam support material which carries the active zinc electrode material. 5 figs.

  10. Electrocatalysts for bifunctional oxygen/air electrodes

    NASA Astrophysics Data System (ADS)

    Nikolova, V.; Iliev, P.; Petrov, K.; Vitanov, T.; Zhecheva, E.; Stoyanova, R.; Valov, I.; Stoychev, D.

    Oxygen reduction and evolution have been studied with respect to the development of bifunctional air/oxygen electrode (BFE). Three groups of catalysts have been prepared: (i) Cu xCo 3- xO 4 by thermal decomposition of mixed nitrate and carbonate precursors; (ii) thin films of Co-Ni-Te-O and Co-Te-O were deposited by vacuum co-evaporation of Co, Ni and TeO 2 and (iii) Co xO v/ZrO 2 films were obtained by electrochemical deposition. The electrochemical behavior of the chemically synthesized catalysts was studied on classical bilayered gas diffusion electrodes (GDEs), where the catalyst is in form of powder. The GDE catalyzed with vacuum deposited catalysts was prepared by direct deposition of the catalyst on gas-supplying layer, thus creating a ready-to-use gas diffusion electrode. Catalysts prepared electrochemically were first deposited on Ni foam and than pressed onto the gas-supplying layer. Different catalysts deposited on classical and originally designed GDEs were compared by their electrochemical performances. Cu 0.3Co 2.7O 4 deposited on a classical bilayered GDE with loading of 50 mg cm -2 exhibits stable current-voltage characteristics after 200 charge-discharge cycles in a real metal hydride-air battery. The electrochemically and vacuum deposited Co xO v/ZrO 2, Co-Ni-Te-O and Co-Te-O films exhibit much higher mass activity compared to Cu 0.2Co 2.8O 4 for both oxygen reduction and evolution reactions. The difference is that the loading of electrochemically and vacuum deposited films is 0.06 mg cm -2 only, which is a substantial advantage from a practical viewpoint.

  11. Method of making an air electrode material having controlled sinterability

    DOEpatents

    Vasilow, Theodore R.; Kuo, Lewis J. H.; Ruka, Roswell J.

    1994-01-01

    A tubular, porous ceramic electrode structure (3) is made from the sintered admixture of doped lanthanum manganite and an additive containing cerium where a solid electrolyte (4), substantially surrounds the air electrode, and a porous outer fuel electrode (7) substantially surrounds the electrolyte, to form a fuel cell (1).

  12. Oxide modified air electrode surface for high temperature electrochemical cells

    DOEpatents

    Singh, Prabhakar; Ruka, Roswell J.

    1992-01-01

    An electrochemical cell is made having a porous cermet electrode (16) and a porous lanthanum manganite electrode (14), with solid oxide electrolyte (15) between them, where the lanthanum manganite surface next to the electrolyte contains a thin discontinuous layer of high surface area cerium oxide and/or praseodymium oxide, preferably as discrete particles (30) in contact with the air electrode and electrolyte.

  13. Method of making an air electrode material having controlled sinterability

    DOEpatents

    Vasilow, T.R.; Kuo, L.J.H.; Ruka, R.J.

    1994-08-30

    A tubular, porous ceramic electrode structure is made from the sintered admixture of doped lanthanum manganite and an additive containing cerium where a solid electrolyte, substantially surrounds the air electrode, and a porous outer fuel electrode substantially surrounds the electrolyte, to form a fuel cell. 2 figs.

  14. Interconnection concepts for rigid micro-electrodes of a dielectric elastomer bending tube actuator

    NASA Astrophysics Data System (ADS)

    Wehrheim, F.; Schlaak, H. F.

    2011-04-01

    A new concept for a tube-like dielectric elastomer actuator (DEA) utilizes rigid micro-electrodes to stabilize the tube structure in azimuthal direction. The individual electrodes are stacked in axial direction within the tube wall. An axial arrangement of a number of those electrode stacks forms a single actuator filament. Application of electrical voltage induces mechanical tension into those stacks by the effect of Maxwell-stress. The interaction of individual electrodes causes a change of the total length of selected actuator filaments. A circular arrangement of a number of actuator filaments allows bending of the tube in any direction. The desired tube actuator is focused on thin walled structures with an outer diameter less than 6 mm and an available wall thickness of less than 0.4 mm. To supply individual electrode stacks with different electric potentials an efficient electrical circuit has to be integrated within the DEA structure. The challenges for the design and fabrication of this circuit primarily lie on the micro-electrode dimensions, the minimization of electrical resistances and severe requirements regarding low mechanical interference. As assumption the actuator electrodes are already stacked and each individual electrode must be accessible at the edge. Considering different surface manufacturing technologies an especially shaped conductor geometry should be deposited onto the electrode edges and the surrounding dielectric. The design of the interconnections considers electrical and mechanical requirements as well as the definition of applicable material parameters. The present work details different concepts for interconnecting rigid electrodes of a thin walled tube-like DEA and discusses related manufacturing technologies.

  15. Vein-style air pumping tube and tire system and method of assembly

    DOEpatents

    Benedict, Robert Leon; Gobinath, Thulasiram; Lin, Cheng-Hsiung; Lamgaday, Robin; Losey, Robert Allen; Griffoin, Jean-Claude Patrice Philippe

    2017-01-03

    An air pumping tube and tire system and method of assembling is provided in which a tire groove is formed to extend into a flexing region of a tire sidewall and a complementary air pumping tube inserts into the tire groove. In the green, uncured air pumping tube condition, one or more check valves are assembled into the air pumping tube through access shafts and align with an internal air passageway of the air pumping tube. Plug components of the system enclose the check valves in the air pumping tube and the check valve-containing green air pumping tube is then cured.

  16. [A Case of Left Vertebral Artery Aneurysm Showing Evoked Potentials on Bilateral Electrode by the Left Vagus Nerve Stimulation to Electromyographic Tracheal Tube].

    PubMed

    Kadoya, Tatsuo; Uehara, Hirofumi; Yamamoto, Toshinori; Shiraishi, Munehiro; Kinoshita, Yuki; Joyashiki, Takeshi; Enokida, Kengo

    2016-02-01

    Previously, we reported a case of brainstem cavernous hemangioma showing false positive responses to electromyographic tracheal tube (EMG tube). We concluded that the cause was spontaneous respiration accompanied by vocal cord movement. We report a case of left vertebral artery aneurysm showing evoked potentials on bilateral electrodes by the left vagus nerve stimulation to EMG tube. An 82-year-old woman underwent clipping of a left unruptured vertebral artery-posterior inferior cerebellar artery aneurysm. General anesthesia was induced with remifentanil, propofol and suxamethonium, and was maintained with oxygen, air, remifentanil and propofol. We monitored somatosensory evoked potentials, motor evoked potentials, and electromyogram of the vocal cord. When the manipulation reached brainstem and the instrument touched the left vagus nerve, evoked potentials appeared on bilateral electrodes. EMG tube is equipped with two electrodes on both sides. We concluded that the left vagus nerve stimulation generated evoked potentials of the left laryngeal muscles, and they were simultaneously detected as potential difference between two electrodes on both sides. EMG tube is used to identify the vagus nerve. However, it is necessary to bear in mind that each vagus nerve stimulation inevitably generates evoked potentials on bilateral electrodes.

  17. Zinc electrode and rechargeable zinc-air battery

    SciTech Connect

    Ross, P.N. Jr.

    1989-06-27

    This patent describes an improved zinc electrode for a rechargeable zinc-air battery comprising an outer frame and a porous foam electrode support within the frame which is treated prior to the deposition of zinc thereon to inhibit the formation of zinc dendrites on the external surface thereof. The outer frame is provided with passageways for circulating an alkaline electrolyte through the treated zinc-coated porous foam. A novel rechargeable zinc-air battery system is also disclosed.

  18. Zinc electrode and rechargeable zinc-air battery

    SciTech Connect

    Ross, Jr., Philip N.

    1989-01-01

    An improved zinc electrode is disclosed for a rechargeable zinc-air battery comprising an outer frame and a porous foam electrode support within the frame which is treated prior to the deposition of zinc thereon to inhibit the formation of zinc dendrites on the external surface thereof. The outer frame is provided with passageways for circulating an alkaline electrolyte through the treated zinc-coated porous foam. A novel rechargeable zinc-air battery system is also disclosed which utilizes the improved zinc electrode and further includes an alkaline electrolyte within said battery circulating through the passageways in the zinc electrode and an external electrolyte circulation means which has an electrolyte reservoir external to the battery case including filter means to filter solids out of the electrolyte as it circulates to the external reservoir and pump means for recirculating electrolyte from the external reservoir to the zinc electrode.

  19. Explosively driven air blast in a conical shock tube

    SciTech Connect

    Stewart, Joel B. Pecora, Collin

    2015-03-15

    Explosively driven shock tubes present challenges in terms of safety concerns and expensive upkeep of test facilities but provide more realistic approximations to the air blast resulting from free-field detonations than those provided by gas-driven shock tubes. Likewise, the geometry of conical shock tubes can naturally approximate a sector cut from a spherically symmetric blast, leading to a better agreement with the blast profiles of free-field detonations when compared to those provided by shock tubes employing constant cross sections. The work presented in this article documents the design, fabrication, and testing of an explosively driven conical shock tube whose goal was to closely replicate the blast profile seen from a larger, free-field detonation. By constraining the blast through a finite area, large blasts (which can add significant damage and safety constraints) can be simulated using smaller explosive charges. The experimental data presented herein show that a close approximation to the free-field air blast profile due to a 1.5 lb charge of C4 at 76 in. can be achieved by using a 0.032 lb charge in a 76-in.-long conical shock tube (which translates to an amplification factor of nearly 50). Modeling and simulation tools were used extensively in designing this shock tube to minimize expensive fabrication costs.

  20. Multisorbent tubes for collecting volatile organic compounds in spacecraft air

    NASA Technical Reports Server (NTRS)

    Matney, M. L.; Beck, S. W.; Limero, T. F.; James, J. T.

    2000-01-01

    The sampling capability of Tenax-TA tubes, used in the National Aeronautics and Space Administration's solid sorbent air sampler to trap and concentrate contaminants from air aboard spacecraft, was improved by incorporating two sorbents within the tubes. Existing tubes containing only Tenax-TA allowed highly volatile compounds to "break through" during collection of a 1.5 L air sample. First the carbon molecular sieve-type sorbents Carboxen 569 and Carbosieve S-III were tested for their ability to quantitatively trap the highly volatile compounds. Breakthrough volumes were determined with the direct method, whereby low ppm levels of methanol or Freon 12 in nitrogen were flowed through the sorbent tubes at 30 mL/min, and breakthrough was detected by gas chromatography. Breakthrough volumes for methanol were about 9 L/g on Carboxen 569 and 11 L/g on Carbosieve S-III; breakthrough volumes for Freon 12 were about 7 L/g on Carboxen 569 and > 26 L/g on Carbosieve S-III. Next, dual-bed tubes containing either Tenax-TA/Carbosieve S-III, Tenax-TA/Carboxen 569, or Carbotrap/Carboxen 569 to a 10-component gas mixture were exposed, in dry and in humidified air (50% relative humidity), and percentage recoveries of each compound were determined. The Tenax-TA/Carboxen 569 combination gave the best overall recoveries (75-114% for the 10 compounds). Acetaldehyde had the lowest recovery (75%) of the 10 compounds, but this value was still an improvement over either the other two sorbent combinations or the original single-sorbent tubes.

  1. Metal | polypyrrole battery with the air regenerated positive electrode

    NASA Astrophysics Data System (ADS)

    Grgur, Branimir N.

    2014-12-01

    Recharge characteristics of the battery based on the electrochemically synthesized polypyrrole cathode and aluminum, zinc, or magnesium anode in 2 M NH4Cl are investigated. It is shown that polypyrrole electrode can be regenerated by the reoxidation with the dissolved oxygen from the air. Using the polypyrrole synthesized on high surface graphite-felt electrode under modest discharge conditions, stable discharge voltage of 1.1 V is obtained. Such behavior is explained by the complex interaction of polypyrrole and hydrogen peroxide produced by the oxygen reduction reaction. The electrochemical characteristics are compared with the zinc-manganese dioxide and zinc-air systems.

  2. Breakthrough of 1,3-dichloropropene and chloropicrin from 600 mg XAD-4 air sampling tubes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurately measuring air concentrations of agricultural fumigants is important for the regulation of air quality. Understanding the conditions under which sorbent tubes can effectively retain such fumigants during sampling is critical in mitigating chemical breakthrough from the tubes and facilitati...

  3. Characterization of gas diffusion electrodes for metal-air batteries

    NASA Astrophysics Data System (ADS)

    Danner, Timo; Eswara, Santhana; Schulz, Volker P.; Latz, Arnulf

    2016-08-01

    Gas diffusion electrodes are commonly used in high energy density metal-air batteries for the supply of oxygen. Hydrophobic binder materials ensure the coexistence of gas and liquid phase in the pore network. The phase distribution has a strong influence on transport processes and electrochemical reactions. In this article we present 2D and 3D Rothman-Keller type multiphase Lattice-Boltzmann models which take into account the heterogeneous wetting behavior of gas diffusion electrodes. The simulations are performed on FIB-SEM 3D reconstructions of an Ag model electrode for predefined saturation of the pore space with the liquid phase. The resulting pressure-saturation characteristics and transport correlations are important input parameters for modeling approaches on the continuum scale and allow for an efficient development of improved gas diffusion electrodes.

  4. Air electrode composition for solid oxide fuel cell

    DOEpatents

    Kuo, L.; Ruka, R.J.; Singhal, S.C.

    1999-08-03

    An air electrode composition for a solid oxide fuel cell is disclosed. The air electrode material is based on lanthanum manganite having a perovskite-like crystal structure ABO{sub 3}. The A-site of the air electrode composition comprises a mixed lanthanide in combination with rare earth and alkaline earth dopants. The B-site of the composition comprises Mn in combination with dopants such as Mg, Al, Cr and Ni. The mixed lanthanide comprises La, Ce, Pr and, optionally, Nd. The rare earth A-site dopants preferably comprise La, Nd or a combination thereof, while the alkaline earth A-site dopant preferably comprises Ca. The use of a mixed lanthanide substantially reduces raw material costs in comparison with compositions made from high purity lanthanum starting materials. The amount of the A-site and B-site dopants is controlled in order to provide an air electrode composition having a coefficient of thermal expansion which closely matches that of the other components of the solid oxide fuel cell. 3 figs.

  5. Air electrode composition for solid oxide fuel cell

    DOEpatents

    Kuo, Lewis; Ruka, Roswell J.; Singhal, Subhash C.

    1999-01-01

    An air electrode composition for a solid oxide fuel cell is disclosed. The air electrode material is based on lanthanum manganite having a perovskite-like crystal structure ABO.sub.3. The A-site of the air electrode composition comprises a mixed lanthanide in combination with rare earth and alkaline earth dopants. The B-site of the composition comprises Mn in combination with dopants such as Mg, Al, Cr and Ni. The mixed lanthanide comprises La, Ce, Pr and, optionally, Nd. The rare earth A-site dopants preferably comprise La, Nd or a combination thereof, while the alkaline earth A-site dopant preferably comprises Ca. The use of a mixed lanthanide substantially reduces raw material costs in comparison with compositions made from high purity lanthanum starting materials. The amount of the A-site and B-site dopants is controlled in order to provide an air electrode composition having a coefficient of thermal expansion which closely matches that of the other components of the solid oxide fuel cell.

  6. Reversible air electrodes integrated with an anion-exchange membrane for secondary air batteries

    NASA Astrophysics Data System (ADS)

    Fujiwara, Naoko; Yao, Masaru; Siroma, Zyun; Senoh, Hiroshi; Ioroi, Tsutomu; Yasuda, Kazuaki

    Reversible air electrodes integrated with a polymer electrolyte membrane have been proposed for use in rechargeable metal-air batteries or unitized regenerative fuel cells to reduce the impact of atmospheric carbon dioxide. Reversible air electrodes were prepared with an anion-exchange membrane (AEM) as a polymer electrolyte membrane and platinum-based catalysts. The AEM at the interface between the alkaline electrolyte and the air electrode layer plays major roles in AEM-type air electrodes as follows: it blocks (a) the permeation of cations in the alkaline electrolyte into the air electrode layer to prevent carbonate precipitation, (b) penetration of the alkaline solution itself, and (c) neutralization of the alkaline electrolyte by carbon dioxide, all of which prevent performance degradation of oxygen reactions. Catalysts for decreasing the overvoltage of oxygen reactions were also investigated with the AEM-type air electrode, and the overall efficiency was improved due to a remarkable decrease in the potential for the oxygen evolution reaction with Pt-Ir catalysts.

  7. Cracking of Composite Modified Alloy 825 Primary Air Port Tubes

    SciTech Connect

    Kish, Joseph R.; Keiser, James R; Singbeil, Douglas; Willoughby, Adam W; Longmire, Hu Foster

    2007-04-01

    Twenty primary air ports fabricated from modified Alloy 825-based composite tubes underwent a metallurgical examination to document the mode and extent of cracking on the external fireside surface of a kraft recovery boiler. Collectively, the crack features found are most consistent with thermal fatigue, but corrosion fatigue cannot be ruled out. Regardless of the true cracking mechanism, temperature cycling is implicated as a critical factor for crack propagation. on the basis of the relative crack lengths observed, membrane welds and tube weld repairs, and their adjacent heat-affected zones, appear to be more susceptible to cracking than the cladding itself. This work suggests that mills should avoid boiler operating conditions that promote large temperature fluctuations, which can cause Alloy 825-based composite tubes to crack.

  8. Natural convection from vertical helical coiled tubes in air

    SciTech Connect

    Ali, M.E.

    1999-07-01

    Helically coiled tubes are used in many engineering applications, such as heating, refrigerating and HVAC systems. They are used also in steam generator and condenser design in power plants because of their large surface area per unit volume. In spite of their widespread use, there is very little information available in the literature on natural convection from such coils. Two experimental investigation have been reported on steady state laminar and transition natural convection from the outer surface of vertically oriented helical coiled tubes in air. Four coils at constant heat flux boundary condition have been used with coil diameter to tube diameter ratio of 16.45 and 23.94. Six more coils have been used at variable surface temperature boundary condition with coil diameter to tube diameter ratio 19.923, 15.904, and 12.798. Local average heat transfer coefficients are obtained for laminar and transition natural convection. The data are correlated with Rayleigh number using the tube diameter as a characteristic length. It has been found that the Nusselt number decreases as Rayleigh number increases for constant heat flux. Transition to turbulent natural convection regime has obtained at a critical Rayleigh number of about 5,000 and it characterizes by a waveform like relation between Nusselt number and Rayleigh number.

  9. Bifunctional air electrodes containing elemental iron powder charging additive

    DOEpatents

    Liu, Chia-tsun; Demczyk, Brian G.; Gongaware, Paul R.

    1982-01-01

    A bifunctional air electrode for use in electrochemical energy cells is made, comprising a hydrophilic layer and a hydrophobic layer, where the hydrophilic layer essentially comprises a hydrophilic composite which includes: (i) carbon; (ii) elemental iron particles having a particle size of between about 25 microns and about 700 microns diameter; (iii) an oxygen evolution material; (iv) a nonwetting agent; and (v) a catalyst, where at least one current collector is formed into said composite.

  10. Novel air electrode for metal-air battery with new carbon material and method of making same

    DOEpatents

    Ross, P.N. Jr.

    1988-06-21

    This invention relates to a rechargeable battery or fuel cell. More particularly, this invention relates to a novel air electrode comprising a new carbon electrode support material and a method of making same. 3 figs.

  11. Fabrication and Characterization of All-Polystyrene Microfluidic Devices with Integrated Electrodes and Tubing

    PubMed Central

    Pentecost, Amber M.; Martin, R. Scott

    2016-01-01

    A new method of fabricating all-polystyrene devices with integrated electrodes and fluidic tubing is described. As opposed to expensive polystyrene (PS) fabrication techniques that use hot embossing and bonding with a heated lab press, this approach involves solvent-based etching of channels and lamination-based bonding of a PS cover, all of which do not need to occur in a clean room. PS has been studied as an alternative microchip substrate to PDMS, as it is more hydrophilic, biologically compatible in terms of cell adhesion, and less prone to absorption of hydrophobic molecules. The etching/lamination-based method described here results in a variety of all-PS devices, with or without electrodes and tubing. To characterize the devices, micrographs of etched channels (straight and intersected channels) were taken using confocal and scanning electron microscopy. Microchip-based electrophoresis with repetitive injections of fluorescein was conducted using a three-sided PS (etched pinched, twin-tee channel) and one-sided PDMS device. Microchip-based flow injection analysis, with dopamine and NO as analytes, was used to characterize the performance of all-PS devices with embedded tubing and electrodes. Limits of detection for dopamine and NO were 130 nM and 1.8 μM, respectively. Cell immobilization studies were also conducted to assess all-PS devices for cellular analysis. This paper demonstrates that these easy to fabricate devices can be attractive alternative to other PS fabrication methods for a wide variety of analytical and cell culture applications. PMID:28191042

  12. Progress in Air Separation with the Vortex Tube

    NASA Technical Reports Server (NTRS)

    Balepin, V.; Rosolt, D.; Petley, D.

    1999-01-01

    The current study is characterized by two distinct phases in the development of the vortex tube (VT) technology as a primary means for in-flight air separation. The purpose of the first phase was to systematically identify parameters that influence oxygen concentration and recovery and to quantify the extent of that influence. To that end, the project team used a series of planned factorial experiments to identify statistically significant variables (factors) and their interactions. These experiments identified a best range of the operating envelope that includes nozzle diameter, orifice diameter, inlet air pressure, and liquid phase content in the inlet air. The best results observed in this envelope were an oxygen content of approximately 68% and a recovery factor of approximately 38%. The primary objectives of the second phase of the current study were to investigate the application effects of the two different air separation efficiency enhancement methods. One of these methods resulted in a concentration increase of 12% and second resulted in a concentration increase of 5%. Several aspects of these methods application are subject to optimize.

  13. Novel configuration of bifunctional air electrodes for rechargeable zinc-air batteries

    NASA Astrophysics Data System (ADS)

    Li, Po-Chieh; Chien, Yu-Ju; Hu, Chi-Chang

    2016-05-01

    A novel configuration of two electrodes containing electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) pressed into a bifunctional air electrode is designed for rechargeable Zn-air batteries. MOC/25BC carbon paper (MOC consisting of α-MnO2 and XC-72 carbon black) and Fe0.1Ni0.9Co2O4/Ti mesh on this air electrode mainly serve as the cathode for the ORR and the anode for the OER, respectively. The morphology and physicochemical properties of Fe0.1Ni0.9Co2O4 are investigated through scanning electron microscopy, inductively coupled plasma-mass spectrometry, and X-ray diffraction. Electrochemical studies comprise linear sweep voltammetry, rotating ring-disk electrode voltammetry, and the full-cell charge-discharge-cycling test. The discharge peak power density of the Zn-air battery with the unique air electrode reaches 88.8 mW cm-2 at 133.6 mA cm-2 and 0.66 V in an alkaline electrolyte under an ambient atmosphere. After 100 charge-discharge cycles at 10 mA cm-2, an increase of 0.3 V between charge and discharge cell voltages is observed. The deep charge-discharge curve (10 h in each step) indicates that the cell voltages of discharge (1.3 V) and charge (1.97 V) remain constant throughout the process. The performance of the proposed rechargeable Zn-air battery is superior to that of most other similar batteries reported in recent studies.

  14. PEDOT:PSS as multi-functional composite material for enhanced Li-air-battery air electrodes

    PubMed Central

    Yoon, Dae Ho; Yoon, Seon Hye; Ryu, Kwang-Sun; Park, Yong Joon

    2016-01-01

    We propose PEDOT:PSS as a multi-functional composite material for an enhanced Li-air-battery air electrode. The PEDOT:PSS layer was coated on the surface of carbon (graphene) using simple method. A electrode containing PEDOT:PSS-coated graphene (PEDOT electrode) could be prepared without binder (such as PVDF) because of high adhesion of PEDOT:PSS. PEDOT electrode presented considerable discharge and charge capacity at all current densities. These results shows that PEDOT:PSS acts as a redox reaction matrix and conducting binder in the air electrode. Moreover, after cycling, the accumulation of reaction products due to side reaction in the electrode was significantly reduced through the use of PEDOT:PSS. This implies that PEDOT:PSS coating layer can suppress the undesirable side reactions between the carbon and electrolyte (and/or Li2O2), which causes enhanced Li-air cell cyclic performance. PMID:26813852

  15. An Inexpensive and Versatile Version of Kundt's Tube for Measuring the Speed of Sound in Air

    ERIC Educational Resources Information Center

    Papacosta, Pangratios; Linscheid, Nathan

    2016-01-01

    Experiments that measure the speed of sound in air are common in high schools and colleges. In the Kundt's tube experiment, a horizontal air column is adjusted until a resonance mode is achieved for a specific frequency of sound. When this happens, the cork dust in the tube is disturbed at the displacement antinode regions. The location of the…

  16. Fabrication of Uniform Nanoporous Oxide Layers on Long Cylindrical Zircaloy Tubes by Anodization Using Multi-Counter Electrodes.

    PubMed

    Park, Yang Jeong; Kim, Jung Woo; Ali, Ghafar; Kim, Hyun Jin; Addad, Yacine; Cho, Sung Oh

    2017-12-01

    We have presented a method to prepare a uniform anodic nanoporous oxide film on the surface of a cylindrical zircaloy (Zr) tube. The distribution of the electric field around the Zr tube determines the distribution of the thickness of the anodic nanoporous oxide film. The electric field generated when a cylindrical Zr tube is electrochemically anodized was simulated by using commercial code COMSOL. When four Pt wires were used as counter electrodes, a uniform electric field was achieved with minimal use of Pt. Based on the simulation results, a cylindrical Zr tube was anodized and the distribution of the thickness of the anodic nanoporous oxide layer was measured by FESEM. Also, mass production of uniform nanoporous anodic oxide films was possible by symmetrically arranging the zircaloy tubes and Pt wires.

  17. Fabrication of Uniform Nanoporous Oxide Layers on Long Cylindrical Zircaloy Tubes by Anodization Using Multi-Counter Electrodes

    NASA Astrophysics Data System (ADS)

    Park, Yang Jeong; Kim, Jung Woo; Ali, Ghafar; Kim, Hyun Jin; Addad, Yacine; Cho, Sung Oh

    2017-01-01

    We have presented a method to prepare a uniform anodic nanoporous oxide film on the surface of a cylindrical zircaloy (Zr) tube. The distribution of the electric field around the Zr tube determines the distribution of the thickness of the anodic nanoporous oxide film. The electric field generated when a cylindrical Zr tube is electrochemically anodized was simulated by using commercial code COMSOL. When four Pt wires were used as counter electrodes, a uniform electric field was achieved with minimal use of Pt. Based on the simulation results, a cylindrical Zr tube was anodized and the distribution of the thickness of the anodic nanoporous oxide layer was measured by FESEM. Also, mass production of uniform nanoporous anodic oxide films was possible by symmetrically arranging the zircaloy tubes and Pt wires.

  18. Carbon-based air electrodes carrying MnO 2 in zinc-air batteries

    NASA Astrophysics Data System (ADS)

    Wei, Zidong; Huang, Wenzhang; Zhang, Shengtao; Tan, Jun

    Catalysts prepared from the carbon black impregnated with manganous nitrate solution and then heated at temperature from 270°C to 450°C were investigated. It was found that the impregnated catalysts heated at temperature of 340°C exhibited the best catalytic activity for oxygen reduction in alkaline electrolyte. It was also found that the XRD spectra of pyrolytic MnO 2 from manganous nitrate over 340°C were different from those below 340°C. The enhanced catalysis of air electrodes was ascribed to the formation of MnO 2 crystal with d-value of 2.72 Å as the impregnated-catalysts was heated at temperature of 340°C. The other factors in preparation of air electrodes were also discussed.

  19. An improved bifunctional oxygen (air) electrode for reversible alkaline fuel cell systems and for rechargeable metal-air batteries

    NASA Astrophysics Data System (ADS)

    Kordesch, K.; Steininger, K.-H.; Tomantschger, K.

    1988-10-01

    Electrodes with a nickel layer of dual pore structure on the electrolyte side and a PTFE-bonded carbon layer on the oxygen (air) side are discussed, with application to space energy storage. During the electrolyis stage, the oxygen fills the large pores of the porous Ni structure with gas. During the discharge cycle, the iron/air or zinc/air cell of the carbon layer operates as a regular oxygen electrode.

  20. Permanent hydrophilization of outer and inner surfaces of polytetrafluoroethylene tubes using ambient air plasma generated by surface dielectric barrier discharges

    SciTech Connect

    Pavliňák, D.; Galmiz, O.; Zemánek, M.; Brablec, A.; Čech, J.; Černák, M.

    2014-10-13

    We present an atmospheric pressure ambient air plasma technique developed for technically simple treatment of inner and/or outer surfaces of plastic tubes and other hollow dielectric bodies. It is based on surface dielectric barrier discharge generating visually diffuse plasma layers along the treated dielectric surfaces using water-solution electrodes. The observed visual uniformity and measured plasma rotational and vibrational temperatures of 333 K and 2350 K indicate that the discharge can be readily applied to material surface treatment without significant thermal effect. This is exemplified by the obtained permanent surface hydrophilization of polytetrafluoroethylene tubes related to the replacement of a high fraction (more than 80%) of the surface fluorine determined by X-ray photoelectron spectroscopy. A tentative explanation of the discharge mechanism based on high-speed camera observations and the discharge current and voltage of measurements is outlined.

  1. Comparisons of Air Radiation Model with Shock Tube Measurements

    NASA Technical Reports Server (NTRS)

    Bose, Deepak; McCorkle, Evan; Bogdanoff, David W.; Allen, Gary A., Jr.

    2009-01-01

    This paper presents an assessment of the predictive capability of shock layer radiation model appropriate for NASA s Orion Crew Exploration Vehicle lunar return entry. A detailed set of spectrally resolved radiation intensity comparisons are made with recently conducted tests in the Electric Arc Shock Tube (EAST) facility at NASA Ames Research Center. The spectral range spanned from vacuum ultraviolet wavelength of 115 nm to infrared wavelength of 1400 nm. The analysis is done for 9.5-10.5 km/s shock passing through room temperature synthetic air at 0.2, 0.3 and 0.7 Torr. The comparisons between model and measurements show discrepancies in the level of background continuum radiation and intensities of atomic lines. Impurities in the EAST facility in the form of carbon bearing species are also modeled to estimate the level of contaminants and their impact on the comparisons. The discrepancies, although large is some cases, exhibit order and consistency. A set of tests and analyses improvements are proposed as forward work plan in order to confirm or reject various proposed reasons for the observed discrepancies.

  2. Bi-functional air electrodes for metal-air batteries. Final report, September 15, 1993--December 14, 1994

    SciTech Connect

    Swette, L.L.; Manoukian, M.; LaConti, A.B.

    1995-12-01

    The program was directed to the need for development of bifunctional air electrodes for Zn-Air batteries for the consumer market. The Zn-Air system, widely used as a primary cell for hearing-aid batteries and as a remote-site power source in industrial applications, has the advantage of high energy density, since it consumes oxygen from the ambient air utilizing a thin, efficient fuel-cell-type gas-diffusion electrode, and is comparatively low in cost. The disadvantages of the current technology are a relatively low rate capability, and the lack of simple reversibility. {open_quotes}Secondary{close_quotes} Zn-Air cells require a third electrode for oxygen evolution or mechanical replacement of the Zinc anodes; thus the development of a bifunctional air electrode (i.e., an electrode that can alternately consume and evolve oxygen) would be a significant advance in Zn-Air cell technology. Evaluations of two carbon-free non-noble metal perovskite-type catalyst systems, La{sub 1-x}CA{sub x}CoO{sub 3} as bifunctional catalysts for potential application in Zn-air batteries were carried out. The technical objectives were to develop higher-surface-area materials and to fabricate reversible electrodes by modifying the hydrophobic/hydrophilic balance of the catalyst-binder structures.

  3. Program and charts for determining shock tube, and expansion tunnel flow quantities for real air

    NASA Technical Reports Server (NTRS)

    Miller, C. G., III; Wilder, S. E.

    1975-01-01

    A computer program in FORTRAN 4 language was written to determine shock tube, expansion tube, and expansion tunnel flow quantities for real-air test gas. This program permits, as input data, a number of possible combinations of flow quantities generally measured during a test. The versatility of the program is enhanced by the inclusion of such effects as a standing or totally reflected shock at the secondary diaphragm, thermochemical-equilibrium flow expansion and frozen flow expansion for the expansion tube and expansion tunnel, attenuation of the flow in traversing the acceleration section of the expansion tube, real air as the acceleration gas, and the effect of wall boundary layer on the acceleration section air flow. Charts which provide a rapid estimation of expansion tube performance prior to a test are included.

  4. Performance of textured carbon on copper electrode multistage depressed collectors with medium-power traveling wave tubes

    NASA Technical Reports Server (NTRS)

    Ramins, Peter; Curren, Arthur N.

    1986-01-01

    Performance of multistage depressed collectors (MDCs) using textured carbon on copper substrate electrode surfaces was evaluated in conjunction with medium-power traveling wave tubes (TWTs). The MDC and TWT overall efficiencies for these electrodes were measured and compared with those obtained with the same TWT and a copper electrode MDC of identical design. Long-term stability of the carbon-coated copper electrode surfaces was investigated by periodic evaluation of TWT-MDC performance over an extended period of continuous wave (CW) operation. Application of textured carbon coating on copper MDC electrode surfaces produced a 13% improvement in both MDC and TWT overall efficiencies for the TWT-MDC tests. During 1600 hr of CW operation with a medium power TWT, no significant changes in MDC performance were noted. This indicated good stability of the textured carbon electrode surfaces. This stability was confirmed by scanning electron microscope examinations of the electrode surfaces before assembly of the MDC and after completion of the test program.

  5. Novel air electrode for metal-air battery with new carbon material and method of making same

    DOEpatents

    Ross, Jr., Philip N.

    1990-01-01

    A novel carbonaceous electrode support material is disclosed characterized by a corrosion rate of 0.03 wt. %/hour or less when measured a5 550 millivolts vs. a Hg/HgO electrode in a 30 wt. % KOH electrolyte a5 30.degree. C. The electrode support material comprises a preselected carbon black material which has been heat-treated by heating the material to a temperature of from about 2500.degree. to about 3000.degree. C. over a period of from about 1 to about 5 hours in an inert atmosphere and then maintaining the preselected carbon black material at this temperature for a period of at least about 1 hour, and preferably about 2 hours, in the inert atmosphere. A carbonaceous electrode suitable for use as an air electrode in a metal-air cell may be made from the electrode support material by shaping and forming it into a catalyst support and then impregnating it with a catalytically active material capable of catalyzing the reaction with oxygen at the air electrode of metal-air cell.

  6. Recurrent tense pneumoperitoneum due to air influx via abdominal wall stoma of a PEG tube.

    PubMed

    Vijayakrishnan, Rajakrishnan; Adhikari, Deep; Anand, Curuchi P

    2010-07-28

    A 70 years old male on ventilatory and circulatory support for sepsis and non ST segment elevation myocardial infarction developed abdominal distension 14 d after placement of a percutaneous endoscopic gastrostomy tube for enteral feeding. Radiography revealed free air in the abdomen and gastrograffin (G) study showed no extravasation into the peritoneum. The G tube was successfully repositioned with mechanical release of air. Imaging showed complete elimination of free air but the patient had a recurrence of pneumoperitoneum. Mechanical release of air with sealing of the abdominal wound was performed. Later, the patient was restarted on tube feeding with no complications. This case demonstrates a late complication of pneumoperitoneum with air leakage from the abdominal wall stoma.

  7. Gradient porous electrode architectures for rechargeable metal-air batteries

    DOEpatents

    Dudney, Nancy J.; Klett, James W.; Nanda, Jagjit; Narula, Chaitanya Kumar; Pannala, Sreekanth

    2016-03-22

    A cathode for a metal air battery includes a cathode structure having pores. The cathode structure has a metal side and an air side. The porosity decreases from the air side to the metal side. A metal air battery and a method of making a cathode for a metal air battery are also disclosed.

  8. An Inexpensive and Versatile Version of Kundt's Tube for Measuring the Speed of Sound in Air

    NASA Astrophysics Data System (ADS)

    Papacosta, Pangratios; Linscheid, Nathan

    2016-01-01

    Experiments that measure the speed of sound in air are common in high schools and colleges. In the Kundt's tube experiment, a horizontal air column is adjusted until a resonance mode is achieved for a specific frequency of sound. When this happens, the cork dust in the tube is disturbed at the displacement antinode regions. The location of the displacement antinodes enables the measurement of the wavelength of the sound that is being used. This paper describes a design that uses a speaker instead of the traditional aluminum rod as the sound source. This allows the use of multiple sound frequencies that yield a much more accurate speed of sound in air.

  9. Stability in alkaline aqueous electrolyte of air electrode protected with fluorinated interpenetrating polymer network membrane

    NASA Astrophysics Data System (ADS)

    Bertolotti, Bruno; Messaoudi, Houssam; Chikh, Linda; Vancaeyzeele, Cédric; Alfonsi, Séverine; Fichet, Odile

    2015-01-01

    We developed original anion exchange membranes to protect air electrodes operating in aqueous lithium-air battery configuration, i.e. supplied with atmospheric air and in concentrated aqueous lithium hydroxide. These protective membranes have an interpenetrating polymer network (IPN) architecture combining a hydrogenated cationic polyelectrolyte network based on poly(epichlorohydrin) (PECH) and a fluorinated neutral network based on perfluoropolyether (Fluorolink® MD700). Two phases, each one rich in one of the polymer, are co-continuous in the materials. This morphology allows combining their properties according to the weight proportions of each polymer. Thus, PECH/Fluorolink IPNs show ionic conductivity varying from 1 to 2 mS cm-1, water uptake from 30 to 90 wt.% and anionic transport number from 0.65 to 0.80 when the PECH proportion varies from 40 to 90 wt.%. These membranes have been systematically assembled on air electrodes. Air electrode protected with PECH/Fluorolink 70/30 IPN shows outstanding stability higher than 1000 h, i.e. a 20-fold increase in the lifetime of the non-modified electrode. This efficient membrane/air electrode assembly is promising for development of alkaline electrolyte based storage or production energy systems, such as metal air batteries or alkaline fuel cells.

  10. Performance and cycle life of carbon- and conductive-based air electrodes for rechargeable Zn-air battery applications

    NASA Astrophysics Data System (ADS)

    Chellapandi Velraj, Samgopiraj

    The development of high-performance, cyclically stable bifunctional air electrodes are critical to the commercial deployment of rechargeable Zn-air batteries. The carbon material predominantly used as support material in the air electrodes due to its higher surface area and good electrical conductivity suffers from corrosion at high oxygen evolution overpotentials. This study addresses the carbon corrosion issues and suggests alternate materials to replace the carbon as support in the air electrode. In this study, Sm0.5Sr0.5CoO3-delta with good electrochemical performance and cyclic lifetime was identified as an alternative catalyst material to the commonly used La0.4Ca 0.6CoO3 catalyst for the carbon-based bifunctional electrodes. Also, a comprehensive study on the effects of catalyst morphology, testing conditions on the cycle life as well as the relevant degradation mechanism for the carbon-based electrode was conducted in this dissertation. The cyclic life of the carbon-based electrodes was strongly dependent on the carbon support material, while the degradation mechanisms were entirely controlled by the catalyst particle size/morphology. Some testing conditions like resting time and electrolyte concentration did not change the cyclic life or degradation mechanism of the carbon-based electrode. The current density used for cyclic testing was found to dictate the degradation mechanism leading to the electrode failure. An alternate way to circumvent the carbon corrosion is to replace the carbon support with a suitable electrically-conductive ceramic material. In this dissertation, LaNi0.9Mn0.1O3, LaNi 0.8Co0.2O3, and NiCo2O4 were synthesized and evaluated as prospective support materials due to their good electrical conductivity and their ability to act as the catalyst needed for the bifunctional electrode. The carbon-free electrodes had remarkably higher catalytic activity for oxygen evolution reaction (OER) when compared to the carbon-based electrode. However

  11. Multiple tube premixing device

    DOEpatents

    Uhm, Jong Ho; Varatharajan, Balachandar; Ziminsky, Willy Steve; Kraemer, Gilbert Otto; Yilmaz, Ertan; Lacy, Benjamin; Stevenson, Christian; Felling, David

    2012-12-11

    The present application provides a premixer for a combustor. The premixer may include a fuel plenum with a number of fuel tubes and a burner tube with a number of air tubes. The fuel tubes extend about the air tubes.

  12. Multiple tube premixing device

    DOEpatents

    Uhm, Jong Ho; Naidu, Balachandar; Ziminksy, Willy Steve; Kraemer, Gilbert Otto; Yilmaz, Ertan; Lacy, Benjamin; Stevenson, Christian; Felling, David

    2013-08-13

    The present application provides a premixer for a combustor. The premixer may include a fuel plenum with a number of fuel tubes and a burner tube with a number of air tubes. The fuel tubes extend about the air tubes.

  13. Variation of the pressure limits of flame propagation with tube diameter for propane-air mixtures

    NASA Technical Reports Server (NTRS)

    Belles, Frank E; Simon, Dorothy M

    1951-01-01

    An investigation was made of the variation of the pressure limits of flame propagation with tube diameter for quiescent propane with tube diameter for quiescent propane-air mixtures. Pressure limits were measured in glass tubes of six different inside diameters, with a precise apparatus. Critical diameters for flame propagation were calculated and the effect of pressure was determined. The critical diameters depended on the pressure to the -0.97 power for stoichiometric mixtures. The pressure dependence decreased with decreasing propane concentration. Critical diameters were related to quenching distance, flame speeds, and minimum ignition energy.

  14. High enthalpy, hypervelocity flows of air and argon in an expansion tube

    NASA Technical Reports Server (NTRS)

    Neely, A. J; Stalker, R. J.; Paull, A.

    1991-01-01

    An expansion tube with a free piston driver has been used to generate quasi-steady hypersonic flows in argon and air at flow velocities in excess of 9 km/s. Irregular test flow unsteadiness has limited the performance of previous expansion tubes, and it has been found that this can be avoided by attention to the interaction between the test gas accelerating expansion and the contact surface in the primary shock tube. Test section measurements of pitot pressure, static pressure and flat plate heat transfer are reported. An approximate analytical theory has been developed for predicting the velocities achieved in the unsteady expansion of the ionizing or dissociating test gas.

  15. Lanthanum manganite-based air electrode for solid oxide fuel cells

    DOEpatents

    Ruka, R.J.; Kuo, L.; Li, B.

    1999-06-29

    An air electrode material for a solid oxide fuel cell is disclosed. The electrode material is based on lanthanum manganite having a perovskite-like crystal structure ABO[sub 3]. The A-site of the air electrode material preferably comprises La, Ca, Ce and at least one lanthanide selected from Sm, Gd, Dy, Er, Y and Nd. The B-site of the electrode material comprises Mn with substantially no dopants. The ratio of A:B is preferably slightly above 1. A preferred air electrode composition is of the formula La[sub w]Ca[sub x]Ln[sub y]Ce[sub z]MnO[sub 3], wherein Ln comprises at least one lanthanide selected from Sm, Gd, Dy, Er, Y and Nd, w is from about 0.55 to about 0.56, x is from about 0.255 to about 0.265, y is from about 0.175 to about 0.185, and z is from about 0.005 to about 0.02. The air electrode material possesses advantageous chemical and electrical properties as well as favorable thermal expansion and thermal cycle shrinkage characteristics. 10 figs.

  16. Lanthanum manganite-based air electrode for solid oxide fuel cells

    DOEpatents

    Ruka, Roswell J.; Kuo, Lewis; Li, Baozhen

    1999-01-01

    An air electrode material for a solid oxide fuel cell is disclosed. The electrode material is based on lanthanum manganite having a perovskite-like crystal structure ABO.sub.3. The A-site of the air electrode material preferably comprises La, Ca, Ce and at least one lanthanide selected from Sm, Gd, Dy, Er, Y and Nd. The B-site of the electrode material comprises Mn with substantially no dopants. The ratio of A:B is preferably slightly above 1. A preferred air electrode composition is of the formula La.sub.w Ca.sub.x Ln.sub.y Ce.sub.z MnO.sub.3, wherein Ln comprises at least one lanthanide selected from Sm, Gd, Dy, Er, Y and Nd, w is from about 0.55 to about 0.56, x is from about 0.255 to about 0.265, y is from about 0.175 to about 0.185, and z is from about 0.005 to about 0.02. The air electrode material possesses advantageous chemical and electrical properties as well as favorable thermal expansion and thermal cycle shrinkage characteristics.

  17. A study of the glow discharge characteristics of contact electrodes at atmospheric pressure in air

    SciTech Connect

    Liu, Wenzheng Sun, Guangliang Li, Chuanhui; Zhang, Rongrong

    2014-04-15

    Electric field distributions and discharge properties of rod-rod contact electrodes were studied under the condition of DBD for the steady generation of atmospheric pressure glow discharge plasma (APGD) in air. We found that under the effect of the initial electrons generated in a nanometer-scale gap, the rod-rod cross-contact electrodes yielded APGD plasma in air. Regarding the rod-rod cross-contact electrodes, increasing the working voltage expanded the strong electric field area of the gas gap so that both discharge area and discharge power increased, and the increase in the number of contact points kept the initial discharge voltage unchanged and caused an increase in the plasma discharge area and discharge power. A mesh-like structure of cross-contact electrodes was designed and used to generate more APGD plasma, suggesting high applicability.

  18. Systemic Air Embolism Associated with Pleural Pigtail Chest Tube Insertion

    PubMed Central

    Alkhankan, Emad; Nusair, Ahmad; Mazagri, Rida

    2016-01-01

    Pleural pigtail catheter placement is associated with many complications including pneumothorax, hemorrhage, and chest pain. Air embolism is a known but rare complication of pleural pigtail catheter insertion and has a high risk of occurrence with positive pressure ventilation. In this case report, we present a 50-year-old male with bilateral pneumonia who developed a pneumothorax while on mechanical ventilation with continuous positive airway pressure mode. During the placement of the pleural pigtail catheter to correct the pneumothorax, the patient developed a sudden left sided body weakness and became unresponsive. An air embolism was identified in the right main cerebral artery, which was fatal. PMID:27630781

  19. Plasticizers, antioxidants, and other contaminants found in air delivered by PVC tubing used in respiratory therapy.

    PubMed

    Hill, Sandra S; Shaw, Brenda R; Wu, Alan H B

    2003-06-01

    Of the many compounds that leach from respiratory therapy tubing into air passing through it, we selected five compounds to analyze. The five compounds are known to be potentially carcinogenic, toxic or known to induce estrogenic activity. Parts-per-million and parts-per-billion concentrations of these species were found in the air passing through the tubing: the plasticizers di-(2-ethylhexyl) phthalate (DEHP) and di-ethyl phthalate (DEP), the antioxidants butylated hydroxy toluene (BHT) and p-nonylphenol (p-NP), and the contaminant (from commercial preparation of DEHP) 2-ethylhexanol (2-EH). These levels are high enough to cause some concern about exposure for patients who use oxygen on a long-term basis, those sensitive or allergic to these species, or those with asthma. A method was developed for analysis of solid tubing samples, showing great variability in concentrations of small, volatile molecules from sample to sample. A method was also developed for pre-concentration of small molecules onto Tenax adsorbants from air passing through the tubing. Both solid samples and adsorbant loaded with analyte were analyzed by direct dynamic thermal desorption gas chromatography mass spectrometry (GCMS). This study does not imply that adverse reactions by patients to chemical compounds leaching from respiratory medical tubing will occur but that further investigation is warranted.

  20. Carbon composite micro- and nano-tubes-based electrodes for detection of nucleic acids

    PubMed Central

    2011-01-01

    The first aim of this study was to fabricate vertically aligned multiwalled carbon nanotubes (MWCNTs). MWCNTs were successfully prepared by using plasma enhanced chemical vapour deposition. Further, three carbon composite electrodes with different content of carbon particles with various shapes and sizes were prepared and tested on measuring of nucleic acids. The dependences of adenine peak height on the concentration of nucleic acid sample were measured. Carbon composite electrode prepared from a mixture of glassy and spherical carbon powder and MWCNTs had the highest sensitivity to nucleic acids. Other interesting result is the fact that we were able to distinguish signals for all bases using this electrode. PMID:21711910

  1. CNT Sheet Air Electrode for the Development of Ultra-High Cell Capacity in Lithium-Air Batteries

    PubMed Central

    Nomura, Akihiro; Ito, Kimihiko; Kubo, Yoshimi

    2017-01-01

    Lithium-air batteries (LABs) are expected to provide a cell with a much higher capacity than ever attained before, but their prototype cells present a limited areal cell capacity of no more than 10 mAh cm−2, mainly due to the limitation of their air electrodes. Here, we demonstrate the use of flexible carbon nanotube (CNT) sheets as a promising air electrode for developing ultra-high capacity in LAB cells, achieving areal cell capacities of up to 30 mAh cm−2, which is approximately 15 times higher than the capacity of cells with lithium-ion battery (LiB) technology (~2 mAh cm−2). During discharge, the CNT sheet electrode experienced enormous swelling to a thickness of a few millimeters because of the discharge product deposition of lithium peroxide (Li2O2), but the sheet was fully recovered after being fully charged. This behavior results from the CNT sheet characteristics of the flexible and fibrous conductive network and suggests that the CNT sheet is an effective air electrode material for developing a commercially available LAB cell with an ultra-high cell capacity. PMID:28378746

  2. Evaluation of Length-of-Stain Gas Indicator Tubes for Measuring Carbon Monoxide in Air.

    ERIC Educational Resources Information Center

    Klaubert, Earl C.; And Others

    Techniques for detection and measurement of carbon monoxide (CO) in air are of interest and utility in many aspects of automotive safety. CO concentrations may range from less than 100 parts per million (ppm), or 0.01 percent, to about 10 percent by volume. Gas indicator tubes have been used for many years primarily as detectors of hazardous gases…

  3. An uniform DBD plasma excited by bipolar nanosecond pulse using wire-cylinder electrode configuration in atmospheric air.

    PubMed

    Jiang, Peng-Chao; Wang, Wen-Chun; Zhang, Shuai; Jia, Li; Yang, De-Zheng; Tang, Kai; Liu, Zhi-Jie

    2014-03-25

    In this study, a bipolar nanosecond pulsed power supply with 15 ns rising time is employed to generate an uniform dielectric barrier discharge using the wire-cylinder electrode configuration in atmospheric air. The images, waveforms of pulse voltage and discharge current, and the optical emission spectra of the discharges are recorded. The rotational and vibrational temperatures of plasma are determined by comparing the simulated spectra with the experimental spectra. The effects of pulse peak voltage, pulse repetition rate and quartz tube diameter on the emission intensities of N2 (C(3)Πu→B(3)Πg, 0-0) and N2(+)B(2)Σu(+)→X(2)Σg(+),0-0 and the rotational and vibrational temperatures have been investigated. It is found that the uniform plasma with low gas temperature can be obtained, and the emission intensities of N2 (C(3)Πu→B(3)Πg, 0-0) and N2(+)B(2)Σu(+)→X(2)Σg(+),0-0 rise with increasing the pulse peak voltage and pulse repetition rate, while decrease as the increase of quartz tube diameter. In addition, under the condition of 28 kV pulse peak voltage, 150 Hz pulse repetition rate and 7 mm quartz tube diameter, the plasma gas temperature is determined to be 330 K. The results also indicate that the plasma gas temperature keep almost constant when increasing the pulse peak voltage and pulse repetition rate but increase with the increase of the quartz tube diameter.

  4. Air-water two-phase flow in a 3-mm horizontal tube

    NASA Astrophysics Data System (ADS)

    Chen, Ing Youn; Chang, Yu-Juei; Wang, Chi-Chung

    2000-01-01

    Two-phase flow pattern and friction characteristics for air-water flow in a 3.17 mm smooth tube are reported in this study. The range of air-water mass flux is between 50 to 700 kg/m2.s and gas quality is between 0.0001 to 0.9. The pressure drop data are analyzed using the concept of the two-phase frictional multipliers and the Martinelli parameter. Experimental data show that the two-phase friction multipliers are strongly related to the flow pattern. Taitel & Dukler flow regime map fails to predict the stratified flow pattern data. Their transition lines between annular-wavy and annular-intermittent give fair agreement with data. A modified correlation from Klimenko and Fyodoros criterion is able to distinguish the annular and stratified data. For two-phase flow in small tubes, the effect of surface tension force should be significantly present as compared to gravitational force. The tested empirical frictional correlations couldn't predict the pressure drop in small tubes for various working fluids. It is suggested to correlate a reliable frictional multiplier for small horizontal tubes from a large database of various working fluids, and to develop the flow pattern dependent models for the prediction of two-phase pressure drop in small tubes. .

  5. Fuel Cell Electrodes for Hydrogen-Air Fuel Cell Assemblies.

    DTIC Science & Technology

    The report describes the design and evaluation of a hydrogen-air fuel cell module for use in a portable hydrid fuel cell -battery system. The fuel ... cell module consists of a stack of 20 single assemblies. Each assembly contains 2 electrically independent cells with a common electrolyte compartment

  6. Low cost stable air electrode material for high temperature solid oxide electrolyte electrochemical cells

    DOEpatents

    Kuo, Lewis J. H.; Singh, Prabhakar; Ruka, Roswell J.; Vasilow, Theodore R.; Bratton, Raymond J.

    1997-01-01

    A low cost, lanthanide-substituted, dimensionally and thermally stable, gas permeable, electrically conductive, porous ceramic air electrode composition of lanthanide-substituted doped lanthanum manganite is provided which is used as the cathode in high temperature, solid oxide electrolyte fuel cells and generators. The air electrode composition of this invention has a much lower fabrication cost as a result of using a lower cost lanthanide mixture, either a natural mixture or an unfinished lanthanide concentrate obtained from a natural mixture subjected to incomplete purification, as the raw material in place of part or all of the higher cost individual lanthanum. The mixed lanthanide primarily contains a mixture of at least La, Ce, Pr, and Nd, or at least La, Ce, Pr, Nd and Sm in its lanthanide content, but can also include minor amounts of other lanthanides and trace impurities. The use of lanthanides in place of some or all of the lanthanum also increases the dimensional stability of the air electrode. This low cost air electrode can be fabricated as a cathode for use in high temperature, solid oxide fuel cells and generators.

  7. Low cost stable air electrode material for high temperature solid oxide electrolyte electrochemical cells

    DOEpatents

    Kuo, L.J.H.; Singh, P.; Ruka, R.J.; Vasilow, T.R.; Bratton, R.J.

    1997-11-11

    A low cost, lanthanide-substituted, dimensionally and thermally stable, gas permeable, electrically conductive, porous ceramic air electrode composition of lanthanide-substituted doped lanthanum manganite is provided which is used as the cathode in high temperature, solid oxide electrolyte fuel cells and generators. The air electrode composition of this invention has a much lower fabrication cost as a result of using a lower cost lanthanide mixture, either a natural mixture or an unfinished lanthanide concentrate obtained from a natural mixture subjected to incomplete purification, as the raw material in place of part or all of the higher cost individual lanthanum. The mixed lanthanide primarily contains a mixture of at least La, Ce, Pr, and Nd, or at least La, Ce, Pr, Nd and Sm in its lanthanide content, but can also include minor amounts of other lanthanides and trace impurities. The use of lanthanides in place of some or all of the lanthanum also increases the dimensional stability of the air electrode. This low cost air electrode can be fabricated as a cathode for use in high temperature, solid oxide fuel cells and generators. 4 figs.

  8. Condensation of the air-steam mixture in a vertical tube condenser

    NASA Astrophysics Data System (ADS)

    Havlík, Jan; Dlouhý, Tomáš

    2016-03-01

    This paper deals with the condensation of water vapour in the presence of non-condensable air. Experimental and theoretical solutions of this problem are presented here. A heat exchanger for the condensation of industrial waste steam containing infiltrated air was designed. The condenser consists of a bundle of vertical tubes in which the steam condenses as it flows downwards with cooling water flowing outside the tubes in the opposite direction. Experiments with pure steam and with mixtures of steam with added air were carried out to find the dependence of the condensation heat transfer coefficient (HTC) on the air concentration in the steam mixture. The experimental results were compared with the theoretical formulas describing the cases. The theoretical determination of the HTC is based on the Nusselt model of steam condensation on a vertical wall, where the analogy of heat and mass transfer is used to take into account the behaviour of air in a steam mixture during the condensation process. The resulting dependencies obtained from the experiments and obtained from the theoretical model have similar results. The significant decrease in the condensation HTC, which begins at very low air concentrations in a steam mixture, was confirmed.

  9. Air electrode material for high temperature electrochemical cells

    DOEpatents

    Ruka, Roswell J.

    1985-01-01

    Disclosed is a solid solution with a perovskite-like crystal structure having the general formula La.sub.1-x-w (M.sub.L).sub.x (Ce).sub.w (M.sub.S1).sub.1-y (M.sub.S2).sub.y O.sub.3 where M.sub.L is Ca, Sr, Ba, or mixtures thereof, M.sub.S1 is Mn, Cr, or mixtures thereof and M.sub.S2 is Ni, Fe, Co, Ti, Al, In, Sn, Mg, Y, Nb, Ta, or mixtures thereof, w is about 0.05 to about 0.25, x+w is about 0.1 to about 0.7, and y is 0 to about 0.5. In the formula, M.sub.L is preferably Ca, w is preferably 0.1 to 0.2, x+w is preferably 0.4 to 0.7, and y is preferably 0. The solid solution can be used in an electrochemical cell where it more closely matches the thermal expansion characteristics of the support tube and electrolyte of the cell.

  10. Effects of atmospheric air plasma treatment of graphite and carbon felt electrodes on the anodic current from Shewanella attached cells.

    PubMed

    Epifanio, Monica; Inguva, Saikumar; Kitching, Michael; Mosnier, Jean-Paul; Marsili, Enrico

    2015-12-01

    The attachment of electrochemically active microorganisms (EAM) on an electrode is determined by both the chemistry and topography of the electrode surface. Pre-treatment of the electrode surface by atmospheric air plasma introduces hydrophilic functional groups, thereby increasing cell attachment and electroactivity in short-term experiments. In this study, we use graphite and carbon felt electrodes to grow the model EAM Shewanella loihica PV-4 at oxidative potential (0.2 V vs. Ag/AgCl). Cell attachment and electroactivity are measured through electrodynamic methods. Atmospheric air plasma pre-treatment increases cell attachment and current output at graphite electrodes by 25%, while it improves the electroactivity of the carbon felt electrodes by 450%. Air plasma pre-treatment decreased the coulombic efficiency on both carbon felt and graphite electrodes by 60% and 80%, respectively. Microbially produced flavins adsorb preferentially at the graphite electrode, and air plasma pre-treatment results in lower flavin adsorption at both graphite and carbon felt electrodes. Results show that air plasma pre-treatment is a feasible option to increase current output in bioelectrochemical systems.

  11. Layered perovskite oxide: a reversible air electrode for oxygen evolution/reduction in rechargeable metal-air batteries.

    PubMed

    Takeguchi, Tatsuya; Yamanaka, Toshiro; Takahashi, Hiroki; Watanabe, Hiroshi; Kuroki, Tomohiro; Nakanishi, Haruyuki; Orikasa, Yuki; Uchimoto, Yoshiharu; Takano, Hiroshi; Ohguri, Nobuaki; Matsuda, Motofumi; Murota, Tadatoshi; Uosaki, Kohei; Ueda, Wataru

    2013-07-31

    For the development of a rechargeable metal-air battery, which is expected to become one of the most widely used batteries in the future, slow kinetics of discharging and charging reactions at the air electrode, i.e., oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), respectively, are the most critical problems. Here we report that Ruddlesden-Popper-type layered perovskite, RP-LaSr3Fe3O10 (n = 3), functions as a reversible air electrode catalyst for both ORR and OER at an equilibrium potential of 1.23 V with almost no overpotentials. The function of RP-LaSr3Fe3O10 as an ORR catalyst was confirmed by using an alkaline fuel cell composed of Pd/LaSr3Fe3O10-2x(OH)2x·H2O/RP-LaSr3Fe3O10 as an open circuit voltage (OCV) of 1.23 V was obtained. RP-LaSr3Fe3O10 also catalyzed OER at an equilibrium potential of 1.23 V with almost no overpotentials. Reversible ORR and OER are achieved because of the easily removable oxygen present in RP-LaSr3Fe3O10. Thus, RP-LaSr3Fe3O10 minimizes efficiency losses caused by reactions during charging and discharging at the air electrode and can be considered to be the ORR/OER electrocatalyst for rechargeable metal-air batteries.

  12. Assemblies of protective anion exchange membrane on air electrode for its efficient operation in aqueous alkaline electrolyte

    NASA Astrophysics Data System (ADS)

    Bertolotti, Bruno; Chikh, Linda; Vancaeyzeele, Cédric; Alfonsi, Séverine; Fichet, Odile

    2015-01-01

    Aqueous alkaline metal-air batteries represent promising energy storage devices when supplied with atmospheric air. However, under this condition, the air electrode shows a very short life time (i.e. 50 h of operation in 5 M LiOH at -10 mA cm-2), mainly due to the precipitation of carbonates inside the electrode porosity. The air electrode can then be protected by an anion exchange membrane on the electrolyte side. In this paper, we demonstrate that the efficiency of this protective membrane depends on the assembly method on the electrode. When a modified poly(epichlorohydrin) (PECH) network is synthesized directly on the electrode, the polymer seeps inside the electrode porosity, and a suitable interface inducing negligible additional polarization in comparison with classical pressure-assembled membranes is obtained. This protected electrode shows improved stability of up to 160 h of operation in 5 M LiOH. This performance is improved to 350 h by adjusting the conductivity and the ionic exchange capacity. Finally, the interest of interpenetrating polymer network (IPN) architecture compared to a single network is confirmed. Indeed, an electrode protected with a PECH/poly(2-hydroxyethyl methacrylate) (PHEMA) IPN is stable for 650 h in 5 M LiOH. In addition, degradation process becomes reversible since the assembly can be regenerated, which is not possible for the bare electrode.

  13. Air Pollution, Neighbourhood Socioeconomic Factors and Neural Tube Defects in the San Joaquin Valley of California

    PubMed Central

    Padula, Amy M.; Yang, Wei; Carmichael, Suzan L.; Tager, Ira B.; Lurmann, Frederick; Hammond, S. Katharine; Shaw, Gary M.

    2015-01-01

    Background Environmental pollutants and neighbourhood socioeconomic factors have been associated with neural tube defects, but the potential impact of interaction between ambient air pollution and neighbourhood socioeconomic factors on the risks of neural tube defects is not well understood. Methods We used data from the California Center of the National Birth Defects Study and the Children’s Health and Air Pollution Study to investigate whether associations between air pollutant exposure in early gestation and neural tube defects were modified by neighbourhood socioeconomic factors in the San Joaquin Valley of California, 1997–2006. Five pollutant exposures, three outcomes and 9 neighbourhood socioeconomic factors were included for a total of 135 investigated associations. Estimates were adjusted for maternal race-ethnicity, education and multivitamin use. Results We present below odds ratios that exclude 1 and a chi-square test of homogeneity p-value of <0.05. We observed increased odds of spina bifida comparing the highest to lowest quartile of particulate matter <10 micrometres (PM10) among those living in a neighbourhood with: a) median household income of less than $30,000 per year (OR 5.1, 95% CI 1.7, 15.3); b) more than 20% living below the federal poverty level (OR 2.6, 95% CI 1.1, 6.0); and c) more than 30% with less than or equal to a high school education (OR 3.2, 95% CI 1.4, 7.4). The ORs were not statistically significant among those higher SES neighbourhoods. Conclusions Our results demonstrate effect modification by neighbourhood socioeconomic factors in the association of particulate matter and neural tube defects in California. PMID:26443985

  14. Electrode

    SciTech Connect

    Clere, T.M.

    1983-08-30

    A 3-dimensional electrode is disclosed having substantially coplanar and substantially flat portions and ribbon-like curved portions, said curved portions being symmetrical and alternating in rows above and below said substantially coplanar, substantially flat portions, respectively, and a geometric configuration presenting in one sectional aspect the appearance of a series of ribbon-like oblate spheroids interrupted by said flat portions and in another sectional aspect, 90/sup 0/ from said one aspect, the appearance of a square wave pattern.

  15. Gas diffusion-type oxygen electrode using perovskite-type oxides for metal-air batteries

    SciTech Connect

    Hyodo, Takeo; Miura, Norio; Yamazoe, Noboru

    1995-12-31

    In order to develop an air cathode of metal-air batteries, oxygen reduction behavior of gas diffusion-type carbon electrodes loaded with perovskite-type oxides, La{sub 1{minus}x}A{prime}{sub x}FeO{sub 3} (A{prime} = Ca, Sr, Ba, 0 {le} x {le} 1.0), was examined in 8 M KOH at 60 C. Among the oxide catalysts tested, La{sub 0.5}Sr{sub 0.5}FeO{sub 3} (specific surface area: 21.5 m{sup 2}{center_dot}g{sup {minus}1}) gave the highest electrode performance. On the basis of electrode reaction kinetics, H{sub 2}O{sub 2} decomposition rates, and temperature programmed desorption of oxygen, it was concluded that such a performance was attributable to the active sites of the oxide for the direct 4-electron reduction of oxygen. Moreover, the electrode using La{sub 0.5}Sr{sub 0.5}FeO{sub 3} was found to be rather stable in a short-term operation for 90 h at 300 mA{center_dot}cm{sup {minus}2}.

  16. Simulation and modelling of charge transport in dye-sensitized solar cells based on carbon nano-tube electrodes

    NASA Astrophysics Data System (ADS)

    Gacemi, Yahia; Cheknane, Ali; Hilal, Hikmat S.

    2013-03-01

    For a better understanding of the mechanisms of dye-sensitized solar cells (DSSCs), based on carbon nano-tube (CNT) electrodes, a phenomenological model is proposed. For modelling purposes, the meso-scopic porous CNT electrode is considered as a homogeneous nano-crystalline structure with thickness L. The CNT electrode is covered with light-absorbing dye molecules, and interpenetrated by the tri-iodide (I-/I3-) redox couple. A simulation platform, designed to study coupled charge transport in such cells, is presented here. The work aims at formulating a mathematical model that describes charge transfer and charge transport within the porous CNT window electrode. The model is based on a pseudo-homogeneous active layer using drift-diffusion transport equations for free electron and ion transport. Based on solving the continuity equation for electrons, the model uses the numerical finite difference method. The numerical solution of the continuity equation produces current-voltage curves that fit the diode equation with an ideality factor of unity. The calculated current-voltage (J-V) characteristics of the illuminated idealized DSSCs (100 mW cm-2, AM1.5), and the different series resistances of the transparent conductor oxide (TCO) layer were introduced into the idealized simulated photo J-V characteristics. The results obtained are presented and discussed in this paper. Thus, for a series resistance of 4 Ω of the TCO layer, the conversion efficiency (η) was 7.49% for the CNT-based cell, compared with 6.11% for the TiO2-based cell. Two recombination kinetic models are used, the electron transport kinetics within the nano-structured CNT film, or the electron transfer rate across the CNT-electrolyte interface. The simulations indicate that both electron and ion transport properties should be considered when modelling CNT-based DSSCs and other similar systems. Unlike conventional polycrystalline solar cells which exhibit carrier recombination, which limits their

  17. Stability of carbon electrodes for aqueous lithium-air secondary batteries

    NASA Astrophysics Data System (ADS)

    Ohkuma, Hirokazu; Uechi, Ichiro; Matsui, Masaki; Takeda, Yasuo; Yamamoto, Osamu; Imanishi, Nobuyuki

    2014-01-01

    The air electrode performance of various carbon materials, such as Ketjen black (KB), acetylene black (AB and AB-S), Vulcan XC-72R (VX), and vapor grown carbon fiber (VGCF) with and without La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) catalyst were examined in an aqueous solution of saturated LiOH with 10 M LiCl in the current density range 0.2-2.0 mA cm-2. The best performance for oxygen reduction and evolution reactions was observed for the KB electrode, which has the highest surface area among the carbon materials examined. A steady over-potential of 0.2 V was obtained for the oxygen reduction reaction using the KB electrode without the catalyst, while the over-potential was 0.15 V for KB with the LSCF catalyst at 2.0 mA cm-2. The over-potentials for the oxygen evolution reaction were slightly higher than those for the oxygen reduction reaction, and gradually increased with the polarization period. Analysis of the gas in the cell after polarization above 0.4 V revealed the evolution of a small amount of CO during the oxygen evolution reaction by the decomposition of carbon in the electrode. The amount of CO evolved was significantly decreased by the addition of LSCF to the carbon electrode.

  18. Autonomous generation of a thermoacoustic solitary wave in an air-filled tube

    NASA Astrophysics Data System (ADS)

    Shimizu, Dai; Sugimoto, Nobumasa

    2016-10-01

    Experiments are performed to demonstrate the autonomous generation of an acoustic solitary wave in an air-filled, looped tube with an array of Helmholtz resonators. The solitary wave is generated spontaneously due to thermoacoustic instability by a pair of stacks installed in the tube and subject to a temperature gradient axially. No external drivers are used to create initial disturbances. Once the solitary wave is generated, it keeps on propagating to circulate along the loop endlessly. The stacks, which are made of ceramics and of many pores of square cross section, are placed in the tube diametrically on exactly the opposite side of the loop, and they are sandwiched by hot and cold (ambient) heat exchangers. When the temperature gradient along both stacks is appropriate, pulses of smooth profiles are generated and propagated in both directions of the tube. From good agreements of not only the pressure profile measured but also the propagation speed with the theory, the pulse is identified as the acoustic solitary wave, and it can be called thermoacoustic solitary wave or thermoacoustic soliton corresponding to the soliton solution of the K-dV equation in one limit.

  19. Radiative cooling of shock-heated air in an explosively driven shock tube.

    NASA Technical Reports Server (NTRS)

    Cooper, D. M.; Borucki, W. J.; Chien, K. Y.

    1972-01-01

    Results are presented of an experimental program to measure the effect of radiative cooling on the enthalpy distribution behind incident shock waves traveling in air. The shock velocity was nominally 16 km/sec and the preshock ambient pressure was varied from 0.4 to 1.6 torr. Shock-tube diameters of 4.7 and 9.4 cm were used to investigate the effects of varying optical depths. Radiative cooling rates were determined from spatially resolved measurements of the profile of the H sub alpha line and from absolute measurements of the continuum radiation. The measured enthalpy profiles are in good agreement with the theoretical predictions of Chien and Compton which account for both nongrey and multidimensional aspects of the radiative transport in the shock tube.

  20. Cracking and Corrosion of Composite Tubes in Black Liquor Recovery Boiler Primary Air Ports

    SciTech Connect

    Keiser, James R.; Singbeil, Douglas L.; Sarma, Gorti B.; Kish, Joseph R.; Yuan, Jerry; Frederick, Laurie A.; Choudhury, Kimberly A.; Gorog, J. Peter; Jetté, Francois R.; Hubbard, Camden R.; Swindeman, Robert W.; Singh, Prett M.; Maziasz, Phillip J.

    2006-10-01

    Black liquor recovery boilers are an essential part of kraft mills. Their design and operating procedures have changed over time with the goal of providing improved boiler performance. These performance improvements are frequently associated with an increase in heat flux and/or operating temperature with a subsequent increase in the demand on structural materials associated with operation at higher temperatures and/or in more corrosive environments. Improvements in structural materials have therefore been required. In most cases the alternate materials have provided acceptable solutions. However, in some cases the alternate materials have solved the original problem but introduced new issues. This report addresses the performance of materials in the tubes forming primary air port openings and, particularly, the problems associated with use of stainless steel clad carbon steel tubes and the solutions that have been identified.

  1. Solid oxide fuel cells, and air electrode and electrical interconnection materials therefor

    DOEpatents

    Bates, J.L.

    1992-09-01

    In one aspect of the invention, an air electrode material for a solid oxide fuel cell comprises Y[sub 1[minus]a]Q[sub a]MnO[sub 3], where Q is selected from the group consisting of Ca and Sr or mixtures thereof and a' is from 0.1 to 0.8. Preferably, a' is from 0.4 to 0.7. In another aspect of the invention, an electrical interconnection material for a solid oxide fuel cell comprises Y[sub 1[minus]b]Ca[sub b]Cr[sub 1[minus]c]Al[sub c]O[sub 3], where b' is from 0.1 to 0.6 and c' is from 0 to 9.3. Preferably, b' is from 0.3 to 0.5 and c' is from 0.05 to 0.1. A composite solid oxide electrochemical fuel cell incorporating these materials comprises: a solid oxide air electrode and an adjacent solid oxide electrical interconnection which commonly include the cation Y, the air electrode comprising Y[sub 1[minus]a]Q[sub a]MnO[sub 3], where Q is selected from the group consisting of Ca and Sr or mixtures thereof and a' is from 0.1 to 0.8, the electrical interconnection comprising Y[sub 1[minus]b]Ca[sub b]Cr[sub 1[minus]c]Al[sub c]O[sub 3], where b' is from 0.1 to 0.6 and c' is from 0.0 to 0.3; a yttrium stabilized solid electrolyte comprising (1[minus]d)ZrO[sub 2]-(d)Y[sub 2]O[sub 3] where d' is from 0.06 to 0.5; and a solid fuel electrode comprising X-ZrO[sub 2], where X' is an elemental metal. 5 figs.

  2. Solid oxide fuel cells, and air electrode and electrical interconnection materials therefor

    DOEpatents

    Bates, J. Lambert

    1992-01-01

    In one aspect of the invention, an air electrode material for a solid oxide fuel cell comprises Y.sub.1-a Q.sub.a MnO.sub.3, where "Q" is selected from the group consisting of Ca and Sr or mixtures thereof and "a" is from 0.1 to 0.8. Preferably, "a" is from 0.4 to 0.7. In another aspect of the invention, an electrical interconnection material for a solid oxide fuel cell comprises Y.sub.1-b Ca.sub.b Cr.sub.1-c Al.sub.c O.sub.3, where "b" is from 0.1 to 0.6 and "c" is from 0 to 9.3. Preferably, "b" is from 0.3 to 0.5 and "c" is from 0.05 to 0.1. A composite solid oxide electrochemical fuel cell incorporating these materials comprises: a solid oxide air electrode and an adjacent solid oxide electrical interconnection which commonly include the cation Y, the air electrode comprising Y.sub.1-a Q.sub.a MnO.sub.3, where "Q" is selected from the group consisting of Ca and Sr or mixtures thereof and "a" is from 0.1 to 0.8, the electrical interconnection comprising Y.sub.1-b Ca.sub.b Cr.sub.1-c Al.sub.c O.sub.3, where "b" is from 0.1 to 0.6 and "c" is from 0.0 to 0.3; a yttrium stabilized solid electrolyte comprising (1-d)ZrO.sub.2 -(d)Y.sub.2 O.sub.3 where "d" is from 0.06 to 0.5; and a solid fuel electrode comprising X-ZrO.sub.2, where "X" is an elemental metal.

  3. Experimental study of lean flammability limits of methane/hydrogen/air mixtures in tubes of different diameters

    SciTech Connect

    Shoshin, Y.L.; Goey, L.P.H. de

    2010-04-15

    Lean limit flames in methane/hydrogen/air mixtures propagating in tubes of internal diameters (ID) of 6.0, 8.9, 12.3, 18.4, 25.2, 35.0, and 50.2 mm have been experimentally studied. The flames propagated upward from the open bottom end of the tube to the closed upper end. The content of hydrogen in the fuel gas has been varied in the range 0-40 mol%. Lean flammability limits have been determined; flame shapes recorded and the visible speed of flame propagation measured. Most of the observed limit flames in tubes with diameters in the range of 8.9-18.4 mm had enclosed shape, and could be characterized as distorted or spherical flame balls. The tendency was observed for mixtures with higher hydrogen content to form smaller size, more uniform flame balls in a wider range of tube diameters. At hydrogen content of 20% or more in the fuel gas, limit flames in largest diameters (35.0 mm and 50.2 mm ID) tubes had small, compared to the tube diameter, size and were ''lens''-shaped. ''Regular'' open-front lean limit flames were observed only for the smallest diameters (6.0 mm and 8.9 mm) and largest diameters (35.0 and 50.2 mm ID), and only for methane/air and (90% CH{sub 4} + 10% H{sub 2})/air mixtures, except for 6 mm ID tube in which all limit flames had open front. In all experiments, except for the lean limit flames in methane/air and (90% CH{sub 4} + 10% H{sub 2})/air mixtures in the 8.9 mm ID tube, and all limit flames in 6.0 mm ID tube, visible flame speeds very weakly depended on the hydrogen content in the fuel gas and were close to- or below the theoretical estimate of the speed of a rising hot bubble. This observation suggests that the buoyancy is the major factor which determines the visible flame speed for studied limit flames, except that last mentioned. A decrease of the lean flammability limit value with decreasing the tube diameter was observed for methane/air and (90% CH{sub 4} + 10% H{sub 2})/air mixtures for tubes having internal diameters in the range

  4. Design, fabrication and performance of small, graphite electrode, multistage depressed collectors with 200-W, CW, 8- to 18-GHz traveling-wave tubes

    NASA Technical Reports Server (NTRS)

    Ebihara, Ben T.; Ramins, Peter

    1987-01-01

    Small multistage depressed collectors (MDC's) which used pyrolytic graphite, ion-beam-textured pyrolytic graphite, and isotropic graphite electrodes were designed, fabricated, and evaluated in conjuntion with 200-W, continuous wave (CW), 8- to 18-GHz traveling-wave tubes (TWT's). The design, construction, and performance of the MDC's are described. The bakeout performance of the collectors, in terms of gas evolution, was indistinguishable from that of typical production tubes with copper collectors. However, preliminary results indicate that some additional radiofrequency (RF) and dc beam processing time (and/or longer or higher temperature bakeouts) may be needed beyond that of typical copper electrode collectors. This is particularly true for pyrolytic graphite electrodes and for TWT's without appendage ion pumps. Extended testing indicated good long-term stability of the textured pyrolytic graphite and isotropic graphite electrode surfaces. The isotropic graphite in particular showed considerable promise as an MDC electrode material because of its high purity, low cost, simple construction, potential for very compact overall size, and relatively low secondary electron emission yield characteristics in the as-machined state. However, considerably more testing experience is required before definitive conclusions on its suitability for electronic countermeasure systems and space TWT's can be made.

  5. Studies on the oxygen reduction catalyst for zinc-air battery electrode

    NASA Astrophysics Data System (ADS)

    Wang, Xianyou; Sebastian, P. J.; Smit, Mascha A.; Yang, Hongping; Gamboa, S. A.

    In this paper, perovskite type La 0.6Ca 0.4CoO 3 as a catalyst of oxygen reduction was prepared, and the structure and performance of the catalysts was examined by means of IR, X-ray diffraction (XRD), and thermogravimetric (TG). Mixed catalysts doped, some metal oxides were put also used. The cathodic polarization curves for oxygen reduction on various catalytic electrodes were measured by linear sweep voltammetry (LSV). A Zn-air battery was made with various catalysts for oxygen reduction, and the performance of the battery was measured with a BS-9300SM rechargeable battery charge/discharge device. The results showed that the perovskite type catalyst (La 0.6Ca 0.4CoO 3) doped with metal oxide is an excellent catalyst for the zinc-air battery, and can effectively stimulate the reduction of oxygen and improve the properties of zinc-air batteries, such as discharge capacity, etc.

  6. Performance of the AIRS Pulse Tube Coolers and Instrument—A First Year in Space

    NASA Astrophysics Data System (ADS)

    Ross, R. G.; Rodriguez, J. I.

    2004-06-01

    Launched on NASA's Aqua platform on May 4, 2002, JPL's Atmospheric Infrared Sounder (AIRS) instrument has completed a successful first year in space and captured a number of important lessons. AIRS is designed to make precision measurements of air temperature over the surface of the Earth and uses a redundant pair of TRW 55 K pulse tube cryocoolers to cool its sensitive IR focal plane. Soon after the instrument went cold, contamination of cryogenic surfaces led to increased cooler loads and the need for decontamination cycles. In addition, single event transients occurred while passing through the South Atlantic Anomaly (SAA) necessitating corrective actions. In November 2002 the fundamental operating strategy of the AIRS instrument was changed from the original strategy of running a single cooler and having the second cooler as a non-operating backup. Instead, based on a new system-level reliability analysis, both coolers began operation simultaneously. This change resolved the contamination and SAA driven interruptions and has enabled unprecedented levels of continuous science measurements. A review of the AIRS instrument cryogenic performance over the past year is presented including its contamination buildup and interrupt history. The reliability analysis conducted to justify two-cooler operation is also reviewed.

  7. Recurrent sinusitis and impairment of eustachian tube function in air passengers and crew.

    PubMed

    Moser, M; Wolf, G

    1990-07-01

    Chronic and recurrent sinusitis, and thus impaired tubular function, are usually caused by isolated lesions of the ethmoid cells. Purulent nasal secretions are transported over the openings of the tubes into the epipharynx. Inflammation and swelling of the mucosa of the tube openings causes stenosis or blockage. Inflammatory foci, usually hidden in the anterior ethmoid cell system, are not always apparent in a plain film of the paranasal sinuses. They appear only in a computed-tomography scan or in a conventional tomogram. Once the diagnosis has been made, a simple, guided endoscopic procedure suffices to alleviate a stenosis, open inflamed ethmoid cells, and restitute ventilation of the nasal sinuses and, thus, tubal function. Radical procedures on the maxillary and frontal sinuses, and plastic operations on deviated nasal septa (which impair the function of the nose and the nasal sinuses only in extreme cases), are thus often unnecessary. Septum deviations are irrelevant to the fitness-to-fly of air personnel as long as the tube and the ventilation of the sinuses function freely. The Valsalva maneuver with otoscopic visualization of the excursion of the eardrum is the most reliable test of tubal function. Tympanometry is used mainly for documentation.

  8. [Calculating method for the necessary lamps and sterile rate in a tube-shaped ultraviolet air washer].

    PubMed

    Xu, Z; Chen, C; Shen, J

    1998-05-01

    It has much more advantage to use the cylindric ultraviolet air washer than to use the ordinary ultraviolet lamps. There was a calculation method for determining necessary lamps in a rectangled ultraviolet air washer, but it had a limiting condition. This paper developed two calculating methods for determining necessary lamps and its sterile rate in a tube-shaped ultraviolet air washer. The sterile rate can be extracted with any parameter. Necessary lamps can also be extracted with its sterile rate.

  9. The application of capnography to differentiate peri-chest tube air leak from parenchymal leak following pulmonary surgery

    PubMed Central

    Walker, William S.

    2014-01-01

    Prolonged air leak is a common complication of pulmonary resection. However, while a bubbling chest drain is commonly related to parenchymal air leakage, it may also be caused by air entering the pleural cavity via an incomplete seal of the tissues at the chest tube insertion site. Examination alone is not sufficient to guide the surgeon as to which of the above complications is responsible for drain bubbling. We describe a simple method, whereby a CO2 monitoring device is attached to the chest drain to determine whether the air loss observed is in fact due to a pulmonary air leak. PMID:24790853

  10. Investigation of Lithium-Air Battery Discharge Product Formed on Carbon Nanotube and Nanofiber Electrodes

    NASA Astrophysics Data System (ADS)

    Mitchell, Robert Revell, III

    Carbon nanotubes have been actively investigated for integration in a wide variety of applications since their discovery over 20 years ago. Their myriad desirable material properties including exceptional mechanical strength, high thermal conductivities, large surface-to-volume ratios, and considerable electrical conductivities, which are attributable to a quantum mechanical ability to conduct electrons ballistically, have continued to motivate interest in this material system. While a variety of synthesis techniques exist, carbon nanotubes and nanofibers are most often conveniently synthesized using chemical vapor deposition (CVD), which involves their catalyzed growth from transition metal nanoparticles. Vertically-aligned nanotube and nanofiber carpets produced using CVD have been utilized in a variety of applications including those related to energy storage. Li-air (Li-O2) batteries have received much interest recently because of their very high theoretical energy densities (3200 Wh/kgLi2O2 ). which make them ideal candidates for energy storage devices for future fully-electric vehicles. During operation of a Li-air battery O2 is reduced on the surface a porous air cathode, reacting with Li-ions to form lithium peroxide (Li-O2). Unlike the intercalation reactions of Li-ion batteries, discharge in a Li-air cell is analogous to an electrodeposition process involving the nucleation and growth of the depositing species on a foreign substrate. Carbon nanofiber electrodes were synthesized on porous substrates using a chemical vapor deposition process and then assembled into Li-O2 cells. The large surface to volume ratio and low density of carbon nanofiber electrodes were found to yield a very high gravimetric energy density in Li-O 2 cells, approaching 75% of the theoretical energy density for Li 2O2. Further, the carbon nanofiber electrodes were found to be excellent platforms for conducting ex situ electron microscopy investigations of the deposition Li2O2 phase

  11. Forced convective flow and heat transfer of upward cocurrent air-water slug flow in vertical plain and swirl tubes

    SciTech Connect

    Chang, Shyy Woei; Yang, Tsun Lirng

    2009-10-15

    This experimental study comparatively examined the two-phase flow structures, pressured drops and heat transfer performances for the cocurrent air-water slug flows in the vertical tubes with and without the spiky twisted tape insert. The two-phase flow structures in the plain and swirl tubes were imaged using the computerized high frame-rate videography with the Taylor bubble velocity measured. Superficial liquid Reynolds number (Re{sub L}) and air-to-water mass flow ratio (AW), which were respectively in the ranges of 4000-10000 and 0.003-0.02 were selected as the controlling parameters to specify the flow condition and derive the heat transfer correlations. Tube-wise averaged void fraction and Taylor bubble velocity were well correlated by the modified drift flux models for both plain and swirl tubes at the slug flow condition. A set of selected data obtained from the plain and swirl tubes was comparatively examined to highlight the impacts of the spiky twisted tape on the air-water interfacial structure and the pressure drop and heat transfer performances. Empirical heat transfer correlations that permitted the evaluation of individual and interdependent Re{sub L} and AW impacts on heat transfer in the developed flow regions of the plain and swirl tubes at the slug flow condition were derived. (author)

  12. Air Damping in a Fan-Shaped Rotational Resonator with Comb Electrodes

    NASA Astrophysics Data System (ADS)

    Uchida, Yuki; Sugano, Koji; Tsuchiya, Toshiyuki; Tabata, Osamu; Ikehara, Tsuyoshi

    We theoretically and experimentally evaluated the damping effect in a rotational resonator with a comb-drive actuator and sensor. The resonator was fabricated from an SOI wafer and has a fan-shaped mass. The underlying substrate was removed using back side deep reactive ion etching. One set of comb electrodes was attached to each side of the mass: one for electrostatic driving and the other for capacitive detection. In our theoretical analysis, the dynamics of the resonator were simplified so that they could be represented by a lumped system. In this lumped system, the damping coefficient was estimated by assuming the damping to be slide film damping and the air flow to be a Stokes flow. The phase shift due to the slide film damping of thick air layers was included in the lumped system. In the experimental evaluation, one side of the rotational combs was removed step-by-step and a half of the mass using a laser trimming tool so that the individual damping effects caused by the comb electrodes and mass could be determined quantitatively. We compared the experimental results with the results of the theoretical analysis and found that the difference in the damping coefficients between the experimental results and results of the theoretical analysis was less than 40%.

  13. New insights into the electrode mechanism of lithium sulfur batteries via air-free post-test analysis.

    PubMed

    Chen, Lin; Dietz Rago, Nancy L; Bloom, Ira D; Shaw, Leon L

    2016-08-02

    Effects of the volume expansion and shrinkage of Li2S cathodes on electrochemical cycle life are investigated via post-test analysis without exposure to air. The engineered electrodes that confine volume changes within micro-reactors have significantly longer life than the electrodes without the micro-reactor structure, providing the first unambiguous evidence of the importance of confining volume changes for improved battery performance.

  14. An air-cooled pulse tube cryocooler with 50 W cooling capacity at 77 K

    NASA Astrophysics Data System (ADS)

    Hu, Jianying; Wang, Xiaotao; Zhu, Jian; Chen, Shuai; Luo, Ercang; Li, Haibin

    2014-01-01

    A pulse tube cryocooler with 50 W cooling capacity at 77 K is developed to cool superconducting devices mounted on automobiles. The envisioned cryocooler weight is less than 40 kg, and the input electric power is less than 1 kW. To achieve these requirements, the working frequency is increased to 75 Hz, and the dual-opposed pistons use gas bearings to reduce compressor weight and volume. The heat from the main heat exchanger is rejected by forced convective air instead of water. The compressor and the cold finger are carefully matched to improve the efficiency. The details of these will be presented in this paper. After some adjustment, a no load temperature for the pulse tube cryocooler of 40 K was achieved with 1 kW input electric power in surroundings at 298 K. At 77 K, the cooling capacity is 50 W. If the main heat exchanger is cooled by water at 293 K, the cooling capacity increases to 64 W, corresponding to a relative Carnot efficiency of 18%.

  15. Zinc/air battery R and D research and development of bifunctional oxygen electrode: Tasks I and II, Final report

    SciTech Connect

    Klein, M.; Viswanathan, S.

    1986-12-01

    Studies were conducted of the bifunctional oxygen electrode. The development of a rechargeable metal-oxygen (air) cell has been hampered to a great extent by the lack of a stable and cost effective oxygen electrode capable of use during both charge and discharge. The first type of bifunctional electrode consists of two distinct catalytifc layers. The oxygen reduction catalyst layer containing a supported gold catalyst is in contact with a hydrophilic nickel layer in which evolution of oxygen takes place. Loadings of gold from 0.5 to 1.0 mg/cm/sup 2/ were investigated; carbon, graphite, metal, and spinel oxides were evaluated as substrates. The second part of the research effort was centered on developing a reversible oxygen electrode containing only one catalytic layer for both reduction and evolution of oxygen. The work was directed specifically to the study of perovskite type of oxides with the composition AA/sup 1/BO/sub 3/ where A is an element of the lanthanide series, A/sup 1/ is an alkaline earth metal and B, a first row transition element. Initial polarization data obtained in unscrubbed air gave a value of approximately 200 millivolts vs Hg/HgO reference electrode at a current density of 50 ma/cm/sup 2/. Electrodes were made both by roll-bonding and by pelletizing techniques and tested for polarization and cycle life. This study also indicates the optimum process conditions for the manufacture of oxides and fabrication of electrodes.

  16. Step-Wise Velocity of an Air Bubble Rising in a Vertical Tube Filled with a Liquid Dispersion of Nanoparticles.

    PubMed

    Cho, Heon Ki; Nikolov, Alex D; Wasan, Darsh T

    2017-03-21

    The motion of air bubbles in tubes filled with aqueous suspensions of nanoparticles (nanofluids) is of practical interest for bubble jets, lab-on-a-chip, and transporting media. Therefore, the focus of this study is the dynamics of air bubbles rising in a tube in a nanofluid. Many authors experimentally and analytically proposed that the velocity of rising air bubbles is constant for long air bubbles suspended in a vertical tube in common liquids (e.g. an aqueous glycerol solution) when the capillary number is larger than 10(-4). For the first time, we report here a systematic study of an air bubble rising in a vertical tube in a nanofluid (e.g. an aqueous silica dioxide nanoparticle suspension, nominal particle size, 19 nm). We varied the bubble length scaled by the diameter of the tubes (L/D), the concentration of the nanofluid (10 and 12.5 v %), and the tube diameter (0.45, 0.47, and 0.50 cm). The presence of the nanoparticles creates a significant change in the bubble velocity compared with the bubble rising in the common liquid with the same bulk viscosity. We observed a novel phenomenon of a step-wise increase in the air bubble rising velocity versus bubble length for small capillary numbers less than 10(-7). This step-wise velocity increase versus the bubble length was not observed in a common fluid. The step-wise velocity increase is attributed to the nanoparticle self-layering phenomenon in the film adjacent to the tube wall. To elucidate the role of the nanoparticle film self-layering on the bubble rising velocity, the effect of the capillary number, the tube diameter (e.g. the capillary pressure), and nanofilm viscosity are investigated. We propose a model that takes into consideration the nanoparticle layering in the film confinement to explain the step-wise velocity phenomenon versus the length of the bubble. The oscillatory film interaction energy isotherm is calculated and the Frenkel approach is used to estimate the film viscosity.

  17. Glow Discharge Emission Spectra in Air with Liquid Electrode Based on Distilled Water

    NASA Astrophysics Data System (ADS)

    Chuchman, M. P.; Mesarosz, L. V.; Shuaibov, A. K.; Kiris, V. V.; Tarasenko, N. V.

    2016-11-01

    The results of spectroscopic studies of a glow discharge plasma at atmospheric pressure in air with an electrode based on distilled water are presented. The parametric effects affecting the discharge emission are analyzed. The dependence of the emission intensity of the various discharge components and their spatial localization in the discharge gap on the current strength is explained by change in the discharge geometry and the conditions of oxidation with increase of the current. It is shown that the composition of the gas mixture in the electrode gap changes with increase of the discharge current from nitrogen-rich (12-19 mA) to rich in water vapor and its dissociation products (19-24 mA). At higher currents, the gas mixture is also rich in the products of plasma chemical reactions and nitric oxide in particular. The redistribution of the radiation intensity of the molecules of nitrogen and its oxide with increase of the current occurs mainly in the cathode region (at the plasma-fluid boundary), where the formation of oxides is improved as a result of increase in the amount of vaporized solution and in the effectiveness of oxidation reactions with increase of the water temperature and discharge current.

  18. Performance and microbial ecology of air-cathode microbial fuel cells with layered electrode assemblies.

    PubMed

    Butler, Caitlyn S; Nerenberg, Robert

    2010-05-01

    Microbial fuel cells (MFCs) can be built with layered electrode assemblies, where the anode, proton exchange membrane (PEM), and cathode are pressed into a single unit. We studied the performance and microbial community structure of MFCs with layered assemblies, addressing the effect of materials and oxygen crossover on the community structure. Four MFCs with layered assemblies were constructed using Nafion or Ultrex PEMs and a plain carbon cloth electrode or a cathode with an oxygen-resistant polytetrafluoroethylene diffusion layer. The MFC with Nafion PEM and cathode diffusion layer achieved the highest power density, 381 mW/m(2) (20 W/m(3)). The rates of oxygen diffusion from cathode to anode were three times higher in the MFCs with plain cathodes compared to those with diffusion-layer cathodes. Microsensor studies revealed little accumulation of oxygen within the anode cloth. However, the abundance of bacteria known to use oxygen as an electron acceptor, but not known to have exoelectrogenic activity, was greater in MFCs with plain cathodes. The MFCs with diffusion-layer cathodes had high abundance of exoelectrogenic bacteria within the genus Geobacter. This work suggests that cathode materials can significantly influence oxygen crossover and the relative abundance of exoelectrogenic bacteria on the anode, while PEM materials have little influence on anode community structure. Our results show that oxygen crossover can significantly decrease the performance of air-cathode MFCs with layered assemblies, and therefore limiting crossover may be of particular importance for these types of MFCs.

  19. Magnetically Diffused Radial Electric-Arc Air Heater Employing Water-Cooled Copper Electrodes

    NASA Technical Reports Server (NTRS)

    Mayo, R. F.; Davis, D. D., Jr.

    1962-01-01

    A magnetically rotated electric-arc air heater has been developed that is novel in that an intense magnetic field of the order of 10,000 to 25,000 gauss is employed. This field is supplied by a coil that is connected in series with the arc. Experimentation with this heater has shown that the presence of an intense magnetic field transverse to the arc results in diffusion of the arc and that the arc has a positive effective resistance. With the field coil in series with the arc, highly stable arc operation is obtained from a battery power supply. External ballast is not required to stabilize the arc when it is operating at maximum power level. The electrode erosion rate is so low that the airstream contamination is no more than 0.07 percent and may be substantially less.

  20. Influence of the angle of inclination of round-finned tubes in a staggered tube bundle on the free convective heat exchange between it and an unbounded air space

    NASA Astrophysics Data System (ADS)

    Kuntysh, V. B.; Samorodov, A. V.

    2010-05-01

    Results of experimental investigations of the average heat transfer from five-row staggered bundles of tubes with knurled spiral fins, operating in the free air-convection regime, in the case where the angel of inclination of the longitudinal axis of the tubes changed from 0 to 60° are presented. The investigations were carried out by the method of complete heat simulation. The average heat transfer was measured in the direction of a free air flow in each row of a tube bundle. The experimental data were generalized by similarity equations for calculating the average heat transfer from the tube bundles and their individual rows in the range of change in the Rayleigh number characteristic of the operating conditions of industrial heat exchangers assembled from finned tubes of the type of the above-indicated tubes.

  1. Secondary-electron-emission losses in multistage depressed collectors and traveling-wave-tube efficiency improvements with carbon collector electrode surfaces

    NASA Technical Reports Server (NTRS)

    Ramins, P.; Ebihara, B. T.

    1986-01-01

    Secondary-electron-emission losses in multistage depressed collectors (MDC's) and their effects on overall traveling-wave-tube (TWT) efficiency were investigated. Two representative TWT's and several computer-modeled MDC's were used. The experimental techniques provide the measurement of both the TWT overall and the collector efficiencies. The TWT-MDC performance was optimized and measured over a wide range of operating conditions, with geometrically identical collectors, which utilized different electrode surface materials. Comparisons of the performance of copper electrodes to that of various forms of carbon, including pyrolytic and iisotropic graphites, were stressed. The results indicate that: (1) a significant improvement in the TWT overall efficiency was obtained in all cases by the use of carbon, rather than copper electrodes, and (2) that the extent of this efficiency enhancement depended on the characteristics of the TWT, the TWT operating point, the MDC design, and collector voltages. Ion textured graphite was found to be particularly effective in minimizing the secondary-electron-emission losses. Experimental and analytical results, however, indicate that it is at least as important to provide a maximum amount of electrostatic suppression of secondary electrons by proper MDC design. Such suppression, which is obtained by ensuring that a substantial suppressing electric field exists over the regions of the electrodes where most of the current is incident, was found to be very effective. Experimental results indicate that, with proper MDC design and the use of electrode surfaces with low secondary-electron yield, degradation of the collector efficiency can be limited to a few percent.

  2. Silver-Copper Nanoalloy Catalyst Layer for Bifunctional Air Electrodes in Alkaline Media.

    PubMed

    Wu, Xiaoqiang; Chen, Fuyi; Jin, Yachao; Zhang, Nan; Johnston, Roy L

    2015-08-19

    A carbon-free and binder-free catalyst layer composed of a Ag-Cu nanoalloy on Ni foam was used as the air cathode in a zinc-air battery for the first time. The Ag-Cu catalyst was prepared using pulsed laser deposition. The structures of the catalysts were found to consist of crystalline Ag-Cu nanoalloy particles with an average size of 2.58 nm embedded in amorphous Cu films. As observed in the X-ray photoelectron spectra, the Ag 3d core levels shifted to higher binding energies, whereas the Cu 2p core levels shifted to lower binding energies, indicating alloying of the silver and copper. Rotating disk electrode measurements indicated that the oxygen reduction reaction (ORR) proceeded through a four-electron pathway on the Ag50Cu50 and Ag90Cu10 nanoalloy catalysts in alkaline solution. Moreover, the catalytic activity of Ag50Cu50 in the ORR is more efficient than that of Ag90Cu10. By performing charge and discharge cycling measurements, the Ag50Cu50 catalyst layer was confirmed to have a maximum power density of approximately 86.3 mW cm(-2) and an acceptable cell voltage at 0.863 V for current densities up to 100 mA cm(-2) in primary zinc-air batteries. In addition, a round-trip efficiency of approximately 50% at a current density of 20 mA cm(-2) was also obtained in the test.

  3. Electrochemical properties of lithium air batteries with Pt100-xRux (0 ≤ x ≤ 100) electrocatalysts for air electrodes

    NASA Astrophysics Data System (ADS)

    Yui, Yuhki; Sakamoto, Shuhei; Nohara, Masaya; Hayashi, Masahiko; Nakamura, Jiro; Komatsu, Takeshi

    2017-02-01

    Electrochemical properties of lithium air secondary battery cells with Pt100-xRux (0 ≤ x ≤ 100) electrocatalysts, prepared by the formic acid reduction method and loaded into air electrodes were examined in 1 mol/l LiTFSA/TEGDME electrolyte solution. Among the cells, the one with the Pt10Ru90 (x = 90)/carbon sample showed the largest discharge capacity of 1014 mAh/g and the lowest average charge voltage of 3.74 V. In addition, the x = 90 sample showed comparatively good cycle stability with discharge capacity of over 800 mAh/g at the 8th cycle. As a result, x = 90 was confirmed to be the optimized composition as the electrocatalyst for the air electrode.

  4. Inflation with air via a facepiece for facilitating insertion of a nasogastric tube: a prospective, randomised, double-blind study.

    PubMed

    Gupta, D; Agarwal, A; Nath, S S; Goswami, D; Saraswat, V; Singh, P K

    2007-02-01

    Insertion of a nasogastric tube is a routine procedure but during anaesthesia it is often difficult and time consuming. One hundred and sixty adults undergoing elective surgery under general anaesthesia were randomly divided into two groups. After induction of anaesthesia, neuromuscular blockade and tracheal intubation, a nasogastric tube was inserted through the nose with the head of the patient in the neutral position, either with or without prior inflation with air via a facepiece attached to a self-inflating bag applied firmly with the face. Insertion of the nasogastric tube was successful in 75/78 (96%) following inflation compared with 54/80 (68%) without inflation (p<0.001). In four patients receiving inflation, a fibreoptic endoscope was passed as far as the upper oesophageal sphincter; this revealed opening of the upper oesophageal sphincter during inflation.

  5. Electrode Configurations in Atmospheric Pressure Plasma Jets

    NASA Astrophysics Data System (ADS)

    Lietz, Amanda M.; Kushner, Mark J.

    2016-09-01

    Atmospheric pressure plasma jets (APPJs) are being studied for emerging medical applications including cancer treatment and wound healing. APPJs typically consist of a dielectric tube through which a rare gas flows, sometimes with an O2 or H2O impurity. In this paper, we present results from a computational study of APPJs using nonPDPSIM, a 2-D plasma hydrodynamics model, with the goal of providing insights on how the placement of electrodes can influence the production of reactive species. Gas consisting of He/O2 = 99.5/0.5 is flowed through a capillary tube at 2 slpm into humid air, and a pulsed DC voltage is applied. An APPJ with two external ring electrodes will be compared with one having a powered electrode inside and a ground electrode on the outside. The consequences on ionization wave propagation and the production of reactive oxygen and nitrogen species (RONS) will be discussed. Changing the electrode configuration can concentrate the power deposition in volumes having different gas composition, resulting in different RONS production. An internal electrode can result in increased production of NOx and HNOx by increasing propagation of the ionization wave through the He dominated plume to outside of the tube where humid air is diffusing into the plume. Work supported by US DOE Office of Fusion Energy Science and the National Science Foundation.

  6. The novel selected-ion flow tube approach to trace gas analysis of air and breath.

    PubMed

    Smith, D; Spanel, P

    1996-01-01

    We present an overview of the development and use of our selected-ion flow tube (SIFT) technique as a sensitive, quantitative method for the rapid, real-time analysis of the trace gas content of atmospheric air and human breath, presenting some pilot data from various research areas in which this method will find valuable application. We show that it is capable of detecting and quantifying trace gases, in complex mixtures such as breath, which are present at partial pressures down to about 10 parts per billion. Following discussions of the principles involved in this SIFT method of analysis, of the experiments which we have carried out to establish its quantitative validity, and of the air and breath sampling techniques involved, we present sample data on the detection and quantification of trace gases on the breath of healthy people and of patients suffering from renal failure and diabetes. We also show how breath ammonia can be accurately quantified from a single breath exhalation and used as an indicator of the presence in the stomach of the bacterium Helicobacter pylori. Health and safety applications are exemplified by analyses of the gases of the gases of cigarette smoke and on the breath of smokers. The value of this analytical method in environmental science is demonstrated by the analyses of petrol vapour, car exhaust emissions and the trace organic vapours detected in town air near a busy road. Final examples of the value of this analytical method are the detection and quantification of the gases emitted from crushed garlic and from breath following the chewing of a mint, which demonstrate its potential in food and flavour research. Throughout the paper we stress the advantages of this SIFT method compared to conventional mass spectrometry for trace gas analysis of complex mixtures, emphasizing its selectivity, sensitivity and real-time analysis capability. Finally, we note that whilst the current SIFT is strictly laboratory based, both transportable and

  7. Spinal cord electrophysiology II: extracellular suction electrode fabrication.

    PubMed

    Garudadri, Suresh; Gallarda, Benjamin; Pfaff, Samuel; Alaynick, William

    2011-02-20

    Development of neural circuitries and locomotion can be studied using neonatal rodent spinal cord central pattern generator (CPG) behavior. We demonstrate a method to fabricate suction electrodes that are used to examine CPG activity, or fictive locomotion, in dissected rodent spinal cords. The rodent spinal cords are placed in artificial cerebrospinal fluid and the ventral roots are drawn into the suction electrode. The electrode is constructed by modifying a commercially available suction electrode. A heavier silver wire is used instead of the standard wire given by the commercially available electrode. The glass tip on the commercial electrode is replaced with a plastic tip for increased durability. We prepare hand drawn electrodes and electrodes made from specific sizes of tubing, allowing consistency and reproducibility. Data is collected using an amplifier and neurogram acquisition software. Recordings are performed on an air table within a Faraday cage to prevent mechanical and electrical interference, respectively.

  8. Experimental study of limit lean methane/air flame in a standard flammability tube using particle image velocimetry method

    SciTech Connect

    Shoshin, Yuriy; Gorecki, Grzegorz; Jarosinski, Jozef; Fodemski, Tadeusz

    2010-05-15

    Lean limit methane/air flame propagating upward in a standard 50 mm diameter and 1.8 m length tube was studied experimentally using particle image velocimetry method. Local stretch rate along the flame front was determined by measured gas velocity distributions. It was found that local stretch rate is maximum at the flame leading point, which is in agreement with earlier theoretical results. Similar to earlier observations, extinction of upward propagating limit flame was observed to start from the flame top. It is stated that the observed behavior of the extinction of the lean limit methane/air flame can not be explained in terms of the coupled effect of flame stretch and preferential diffusion. To qualitatively explain the observed extinction behavior, it is suggested that the positive strain-induced flame stretch increases local radiation heat losses from the flame front. An experimental methodology for PIV measurements in a round tube is described. (author)

  9. Nitric oxide formation in a lean, premixed-prevaporized jet A/air flame tube: An experimental and analytical study

    NASA Technical Reports Server (NTRS)

    Lee, Chi-Ming; Bianco, Jean; Deur, John M.; Ghorashi, Bahman

    1992-01-01

    An experimental and analytical study was performed on a lean, premixed-prevaporized Jet A/air flame tube. The NO(x) emissions were measured in a flame tube apparatus at inlet temperatures ranging from 755 to 866 K (900 to 1100 F), pressures from 10 to 15 atm, and equivalence ratios from 0.37 to 0.62. The data were then used in regressing an equation to predict the NO(x) production levels in combustors of similar design. Through an evaluation of parameters it was found that NO(x) is dependent on adiabatic flame temperature and combustion residence time, yet independent of pressure and inlet air temperature for the range of conditions studied. This equation was then applied to experimental data that were obtained from the literature, and a good correlation was achieved.

  10. Fuel cell tubes and method of making same

    DOEpatents

    Borglum, Brian P.

    1999-11-30

    A method of manufacturing porous ceramic tubes for fuel cells with improved properties and higher manufacturing yield is disclosed. The method involves extruding a closed end fuel cell tube, such as an air electrode of a solid oxide fuel cell, in which the closed end also functions as the sintering support. The resultant fuel cell tube has a superior porosity distribution which allows improved diffusion of oxygen at the closed end of the tube during operation of the fuel cell. Because this region has the highest current density, performance enhancement and improved reliability of the fuel cell tube result. Furthermore, the higher manufacturing yield associated with the present method decreases the overall fuel cell cost. A method of manufacturing porous ceramic tubes for fuel cells with improved properties and higher manufacturing yield is disclosed. The method involves extruding a closed end fuel cell tube, such as an air electrode of a solid oxide fuel cell, in which the closed end also functions as the sintering support. The resultant fuel cell tube has a superior porosity distribution which allows improved diffusion of oxygen at the closed end of the tube during operation of the fuel cell. Because this region has the highest current density, performance enhancement and improved reliability of the fuel cell tube result. Furthermore, the higher manufacturing yield associated with the present method decreases the overall fuel cell cost.

  11. Equivalent ambipolar carrier injection of electrons and holes with Au electrodes in air-stable field effect transistors

    SciTech Connect

    Kanagasekaran, Thangavel E-mail: Shimotani@m.tohoku.ac.jp Ikeda, Susumu; Kumashiro, Ryotaro; Shimotani, Hidekazu E-mail: Shimotani@m.tohoku.ac.jp Shang, Hui; Tanigaki, Katsumi E-mail: Shimotani@m.tohoku.ac.jp

    2015-07-27

    Carrier injection from Au electrodes to organic thin-film active layers can be greatly improved for both electrons and holes by nano-structural surface control of organic semiconducting thin films using long-chain aliphatic molecules on a SiO{sub 2} gate insulator. In this paper, we demonstrate a stark contrast for a 2,5-bis(4-biphenylyl)bithiophene (BP2T) active semiconducting layer grown on a modified SiO{sub 2} dielectric gate insulator between two different modifications of tetratetracontane and poly(methyl methacrylate) thin films. Important evidence that the field effect transistor (FET) characteristics are independent of electrode metals with different work functions is given by the observation of a conversion of the metal-semiconductor contact from the Schottky limit to the Bardeen limit. An air-stable light emitting FET with an Au electrode is demonstrated.

  12. Sound propagation in narrow tubes including effects of viscothermal and turbulent damping with application to charge air coolers

    NASA Astrophysics Data System (ADS)

    Knutsson, Magnus; Åbom, Mats

    2009-02-01

    Charge air coolers (CACs) are used on turbocharged internal combustion engines to enhance the overall gas-exchange performance. The cooling of the charged air results in higher density and thus volumetric efficiency. It is also important for petrol engines that the knock margin increases with reduced charge air temperature. A property that is still not very well investigated is the sound transmission through a CAC. The losses, due to viscous and thermal boundary layers as well as turbulence, in the narrow cooling tubes result in frequency dependent attenuation of the transmitted sound that is significant and dependent on the flow conditions. Normally, the cross-sections of the cooling tubes are neither circular nor rectangular, which is why no analytical solution accounting for a superimposed mean flow exists. The cross-dimensions of the connecting tanks, located on each side of the cooling tubes, are large compared to the diameters of the inlet and outlet ducts. Three-dimensional effects will therefore be important at frequencies significantly lower than the cut-on frequencies of the inlet/outlet ducts. In this study the two-dimensional finite element solution scheme for sound propagation in narrow tubes, including the effect of viscous and thermal boundary layers, originally derived by Astley and Cummings [Wave propagation in catalytic converters: Formulation of the problem and finite element scheme, Journal of Sound and Vibration 188 (5) (1995) 635-657] is used to extract two-ports to represent the cooling tubes. The approximate solutions for sound propagation, accounting for viscothermal and turbulent boundary layers derived by Dokumaci [Sound transmission in narrow pipes with superimposed uniform mean flow and acoustic modelling of automobile catalytic converters, Journal of Sound and Vibration 182 (5) (1995) 799-808] and Howe [The damping of sound by wall turbulent shear layers, Journal of the Acoustical Society of America 98 (3) (1995) 1723-1730], are

  13. Study on electrical characteristics of barrier-free atmospheric air diffuse discharge generated by nanosecond pulses and long wire electrodes

    SciTech Connect

    Li, Lee Liu, Yun-Long; Teng, Yun; Liu, Lun; Pan, Yuan

    2014-07-15

    In room-temperature atmospheric air, the large-scale diffuse plasmas can be generated via high-voltage nanosecond pulses with short rise-time and wire electrodes. Diffuse discharge with the wire electrode length up to 110.0 cm and the discharge spacing of several centimeters has been investigated in this paper. Electrical characteristics of diffuse discharge have been analyzed by their optical photographs and measuring of the voltage and current waveforms. Experimental results show the electrode spacing, and the length of wire electrodes can influence the intensity and mode transition of diffuse discharge. The characteristic of current waveforms is that there are several current oscillation peaks at the time of applied pulsed voltage peak, and at the tail of applied pulse, the conduction current component will compensate the displacement one so that the measured current is unidirectional in diffuse discharge mode. The transition from diffuse discharge to arc discharge is always with the increasing of conduction current density. As for nanosecond pulses with long tail, the long wire electrodes are help for generating non-equilibrium diffuse plasmas.

  14. Performance of a small, graphite electrode, multistage depressed collector with a 500-W, continuous wave, 4.8- to 9.6-GHz traveling wave tube

    NASA Technical Reports Server (NTRS)

    Ramins, Peter; Lesny, Gary G.; Ebihara, Ben T.; Peet, Shelly

    1988-01-01

    A small, isotropic graphite multistage depressed collector (MDC) and a short permanent magnet refocuser were designed, fabricated, and evaluated in conjunction with a 500-W, continuous-wave (CW), 4.8 to 9.6 GHz traveling wave tube (TWT). A novel performance optimization system and technique were used to optimize the TWT-MDC performance for saturated broad-band operation. The MDC performance was evaluated in both four- and three-stage configurations. Average TWT overall and four-stage collector efficiencies of 43.8 and 82.6 percent, respectively, were obtained for saturated octave-bandwidth operation. The isotropic graphite electrode material performed well, and shows considerable promise. However, considerably more test experience is required before definitive conclusions on its suitability for space and airborne TWT's can be made.

  15. QUANTIZING TUBE

    DOEpatents

    Jensen, A.S.; Gray, G.W.

    1958-07-01

    Beam deflection tubes are described for use in switching or pulse amplitude analysis. The salient features of the invention reside in the target arrangement whereby outputs are obtained from a plurality of collector electrodes each correspondlng with a non-overlapping range of amplitudes of the input sigmal. The tube is provded with mcans for deflecting the electron beam a1ong a line in accordance with the amplitude of an input signal. The target structure consists of a first dymode positioned in the path of the beam wlth slots spaced a1ong thc deflection line, and a second dymode posltioned behind the first dainode. When the beam strikes the solid portions along the length of the first dymode the excited electrons are multiplied and collected in separate collector electrodes spaced along the beam line. Similarly, the electrons excited when the beam strikes the second dynode are multiplied and collected in separate electrodes spaced along the length of the second dyode.

  16. Rechargeable Lithium-Air Batteries: Development of Ultra High Specific Energy Rechargeable Lithium-Air Batteries Based on Protected Lithium Metal Electrodes

    SciTech Connect

    2010-07-01

    BEEST Project: PolyPlus is developing the world’s first commercially available rechargeable lithium-air (Li-Air) battery. Li-Air batteries are better than the Li-Ion batteries used in most EVs today because they breathe in air from the atmosphere for use as an active material in the battery, which greatly decreases its weight. Li-Air batteries also store nearly 700% as much energy as traditional Li-Ion batteries. A lighter battery would improve the range of EVs dramatically. Polyplus is on track to making a critical breakthrough: the first manufacturable protective membrane between its lithium–based negative electrode and the reaction chamber where it reacts with oxygen from the air. This gives the battery the unique ability to recharge by moving lithium in and out of the battery’s reaction chamber for storage until the battery needs to discharge once again. Until now, engineers had been unable to create the complex packaging and air-breathing components required to turn Li-Air batteries into rechargeable systems.

  17. Smooth- and enhanced-tube heat transfer and pressure drop : Part I. Effect of Prandtl number with air, water, and glycol/water mixtures.

    SciTech Connect

    Obot, N. T.; Das, L.; Rabas, T. J.

    2000-11-14

    An extensive experimental investigation was carried out to determine the pressure drop and heat transfer characteristics in laminar, transitional, and turbulent flow through one smooth tube and twenty-three enhanced tubes. The working fluids for the experiments were air, water, ethylene glycol, and ethylene glycol/water mixtures; Prandtl numbers (Pr) ranged from 0.7 to 125.3. The smooth-tube experiments were carried out with Pr values of 0.7, 6.8, 24.8, 39.1, and 125.3; Pr values of 0.7, 6.8, and 24.8 were tested with enhanced tubes. Reynolds number (Re) range (based on the maximum internal diameter of a tube) was 200 to 55,000, depending on Prandtl number and tube geometry. The results are presented and discussed in this paper.

  18. Multifunctional reference electrode

    DOEpatents

    Redey, L.; Vissers, D.R.

    1981-12-30

    A multifunctional, low mass reference electrode of a nickel tube, thermocouple means inside the nickel tube electrically insulated therefrom for measuring the temperature thereof, a housing surrounding the nickel tube, an electrolyte having a fixed sulfide ion activity between the housing and the outer surface of the nickel tube forming the nickel/nickel sulfide/sulfide half-cell are described. An ion diffusion barrier is associated with the housing in contact with the electrolyte. Also disclosed is a cell using the reference electrode to measure characteristics of a working electrode.

  19. Multifunctional reference electrode

    DOEpatents

    Redey, Laszlo; Vissers, Donald R.

    1983-01-01

    A multifunctional, low mass reference electrode of a nickel tube, thermocouple means inside the nickel tube electrically insulated therefrom for measuring the temperature thereof, a housing surrounding the nickel tube, an electrolyte having a fixed sulfide ion activity between the housing and the outer surface of the nickel tube forming the nickel/nickel sulfide/sulfide half-cell. An ion diffusion barrier is associated with the housing in contact with the electrolyte. Also disclosed is a cell using the reference electrode to measure characteristics of a working electrode.

  20. Swozzle based burner tube premixer including inlet air conditioner for low emissions combustion

    DOEpatents

    Tuthill, Richard Sterling; Bechtel, II, William Theodore; Benoit, Jeffrey Arthur; Black, Stephen Hugh; Bland, Robert James; DeLeonardo, Guy Wayne; Meyer, Stefan Martin; Taura, Joseph Charles; Battaglioli, John Luigi

    2002-01-01

    A burner for use in a combustion system of a heavy-duty industrial gas turbine includes a fuel/air premixer having an air inlet, a fuel inlet, and an annular mixing passage. The fuel/air premixer mixes fuel and air into a uniform mixture for injection into a combustor reaction zone. The burner also includes an inlet flow conditioner disposed at the air inlet of the fuel/air premixer for controlling a radial and circumferential distribution of incoming air. The pattern of perforations in the inlet flow conditioner is designed such that a uniform air flow distribution is produced at the swirler inlet annulus in both the radial and circumference directions. The premixer includes a swozzle assembly having a series of preferably air foil shaped turning vanes that impart swirl to the airflow entering via the inlet flow conditioner. Each air foil contains internal fuel flow passages that introduce natural gas fuel into the air stream via fuel metering holes that pass through the walls of the air foil shaped turning vanes. By injecting fuel in this manner, an aerodynamically clean flow field is maintained throughout the premixer. By injecting fuel via two separate passages, the fuel/air mixture strength distribution can be controlled in the radial direction to obtain optimum radial concentration profiles for control of emissions, lean blow outs, and combustion driven dynamic pressure activity as machine and combustor load are varied.

  1. Time-lag properties of corona streamer discharges between impulse sphere and dc needle electrodes under atmospheric air conditions.

    PubMed

    Okano, Daisuke

    2013-02-01

    In this study of corona streamer discharges from an impulse generator using a dc power supply, the relationship of the discharge time-lag with the dc bias voltage between the sphere-to-needle electrodes under atmospheric conditions is investigated. Devices utilizing corona discharges have been used to purify air or water, destroy bacteria, and to remove undesirable substances, and in order to achieve fast response times and high power efficiencies in such devices, it is important to minimize the time-lag of the corona discharge. Our experimental results show that (a) the discharge path of a negatively biased needle electrode will be straighter than that of a positively biased needle and (b) the discharge threshold voltage in both the positive and the negative needle electrodes is nearly equal to 33 kV. By expressing the discharge voltage as a power function of time-lag, the extent of corona generation can be quantitatively specified using the exponent of this power function. The observed behavior of a corona streamer discharge between the negative spherical and the positive needle electrodes indicates that the largest power exponent is associated with the shortest time-lag, owing to the reduction in the statistical time-lag in the absence of a formative time-lag.

  2. Time-lag properties of corona streamer discharges between impulse sphere and dc needle electrodes under atmospheric air conditions

    NASA Astrophysics Data System (ADS)

    Okano, Daisuke

    2013-02-01

    In this study of corona streamer discharges from an impulse generator using a dc power supply, the relationship of the discharge time-lag with the dc bias voltage between the sphere-to-needle electrodes under atmospheric conditions is investigated. Devices utilizing corona discharges have been used to purify air or water, destroy bacteria, and to remove undesirable substances, and in order to achieve fast response times and high power efficiencies in such devices, it is important to minimize the time-lag of the corona discharge. Our experimental results show that (a) the discharge path of a negatively biased needle electrode will be straighter than that of a positively biased needle and (b) the discharge threshold voltage in both the positive and the negative needle electrodes is nearly equal to 33 kV. By expressing the discharge voltage as a power function of time-lag, the extent of corona generation can be quantitatively specified using the exponent of this power function. The observed behavior of a corona streamer discharge between the negative spherical and the positive needle electrodes indicates that the largest power exponent is associated with the shortest time-lag, owing to the reduction in the statistical time-lag in the absence of a formative time-lag.

  3. Effect of Mach number, valve angle and length to diameter ratio on thermal performance in flow of air through Ranque Hilsch vortex tube

    NASA Astrophysics Data System (ADS)

    Devade, Kiran D.; Pise, Ashok T.

    2017-01-01

    Ranque Hilsch vortex tube is a device that can produce cold and hot air streams simultaneously from pressurized air. Performance of vortex tube is influenced by a number of geometrical and operational parameters. In this study parametric analysis of vortex tube is carried out. Air is used as the working fluid and geometrical parameters like length to diameter ratio (15, 16, 17, 18), exit valve angles (30°-90°), orifice diameters (5, 6 and 7 mm), 2 entry nozzles and tube divergence angle 4° is used for experimentation. Operational parameters like pressure (200-600 kPa), cold mass fraction (0-1) is varied and effect of Mach number at the inlet of the tube is investigated. The vortex tube is tested at sub sonic (0 < Ma < 1), sonic (Ma = 1) and supersonic (1 < Ma < 2) Mach number, and its effect on thermal performance is analysed. As a result it is observed that, higher COP and low cold end temperature is obtained at subsonic Ma. As CMF increases, COP rises and cold and temperature drops. Optimum performance of the tube is observed for CMF up to 0.5. Experimental correlations are proposed for optimum COP. Parametric correlation is developed for geometrical and operational parameters.

  4. Internal-liquid-film-cooling Experiments with Air-stream Temperatures to 2000 Degrees F. in 2- and 4-inch-diameter Horizontal Tubes

    NASA Technical Reports Server (NTRS)

    Kinney, George R; Abramson, Andrew E; Sloop, John L

    1952-01-01

    Report presents the results of an investigation conducted to determine the effectiveness of liquid-cooling films on the inner surfaces of tubes containing flowing hot air. Experiments were made in 2- and 4-inch-diameter straight metal tubes with air flows at temperatures from 600 degrees to 2000 degrees F. and diameter Reynolds numbers from 2.2 to 14 x 10(5). The film coolant, water, was injected around the circumference at a single axial position on the tubes at flow rates from 0.02 to .24 pound per second per foot of tube circumference (0.8 to 12 percent of the air flow). Liquid-coolant films were established and maintained around and along the tube wall in concurrent flow with the hot air. The results indicated that, in order to film cool a given surface area with as little coolant flow as possible, it may be necessary to limit the flow of coolant introduced at a single axial position and to introduce it at several axial positions. The flow rate of inert coolant required to maintain liquid-film cooling over a given area of tube surface can be estimated when the gas-flow conditions are known by means of a generalized plot of the film-cooling data.

  5. Incident shock-wave characteristics in air, argon, carbon dioxide, and helium in a shock tube with unheated helium driver

    NASA Technical Reports Server (NTRS)

    Miller, C. G., III; Jones, J. J.

    1975-01-01

    Incident shock-wave velocities were measured in the Langley 6-inch expansion tube, operated as a shock tube, with air, argon, carbon dioxide, and helium as test gases. Unheated helium was used as the driver gas and most data were obtained at pressures of approximately 34 and 54 MN/sq m. A range of pressure ratio across the diaphragm was obtained by varying the quiescent test-gas pressure, for a given driver pressure, from 0.0276 to 34.5 kN/sq m. Single- and double-diaphragm modes of operation were employed and diaphragms of various materials tested. Shock velocity was determined from microwave interferometer measurements, response of pressure transducers positioned along interferometer measurements, response of pressure transducers positioned along the driven section (time-of-arrival gages), and to a lesser extent, measured tube-wall pressure. Velocities obtained from these methods are compared and limitations of the methods discussed. The present results are compared with theory and the effects of diaphragm mode (single or double diaphragm), diaphragm material, heating of the driver gas upon pressurization of the driver section, diaphragm opening time, interface mixing, and two-dimensional (nonplanar) flow are discussed.

  6. Tri (2-chloroisopropyl) phosphate--an unexpected organochlorine contaminant in some charcoal air-sampling sorbent tubes.

    PubMed

    van Netten, C; Brands, R; Park, J; Deverall, R

    1991-09-01

    Air sampling in a government building was necessary in response to reports of a cancer cluster. SKC (Eighty Four, Pa.) charcoal coconut shell-based sorbent tubes (226-01 lot 120) were recommended for this procedure. A recently purchased supply was present at the University of British Columbia and consequently was used for this particular study. Analysis of the front charcoal section showed the presence of a flame retardant, tri (2-chloroisopropyl) phosphate, which was confirmed by gas liquid chromatography (GLC) and mass spectrometry analysis. In an effort to identify the source of this fire retardant in the building, it became apparent from the analysis done on unknown field blanks that tri (2-chloroisopropyl) phosphate was a contaminant of the sorbent tubes used. Analysis of additional blank tubes identified the foam separators as the most likely source of contamination. Levels of tri (2-chloroisopropyl) phosphate in the front charcoal section ranged from 1.3 to 5.9 micrograms. The foam separator contained between 11.4 and 16.5 micrograms, and the backup charcoal section contained between 14.5 and 24.0 micrograms of tri (2-chloroisopropyl) phosphate. In addition, another flame retardant, tri (1,3 dichloro-2-propyl) phosphate was also found. Because these contaminants have long column retention times in GLC, it may not be apparent that these contaminants are present and consequently are likely to have modified the sorbent characteristics of the activated charcoal. Another batch of sorbent tubes bearing the same catalog number and lot number was purchased from the supplier; no flame retardants were found in this batch.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Tri (2-chloroisopropyl) phosphate--an unexpected organochlorine contaminant in some charcoal air-sampling sorbent tubes

    SciTech Connect

    van Netten, C.; Brands, R.; Park, J.; Deverall, R. )

    1991-09-01

    Air sampling in a government building was necessary in response to reports of a cancer cluster. SKC (Eighty Four, Pa.) charcoal coconut shell-based sorbent tubes (226-01 lot 120) were recommended for this procedure. A recently purchased supply was present at the University of British Columbia and consequently was used for this particular study. Analysis of the front charcoal section showed the presence of a flame retardant, tri (2-chloroisopropyl) phosphate, which was confirmed by gas liquid chromatography (GLC) and mass spectrometry analysis. In an effort to identify the source of this fire retardant in the building, it became apparent from the analysis done on unknown field blanks that tri (2-chloroisopropyl) phosphate was a contaminant of the sorbent tubes used. Analysis of additional blank tubes identified the foam separators as the most likely source of contamination. Levels of tri (2-chloroisopropyl) phosphate in the front charcoal section ranged from 1.3 to 5.9 micrograms. The foam separator contained between 11.4 and 16.5 micrograms, and the backup charcoal section contained between 14.5 and 24.0 micrograms of tri (2-chloroisopropyl) phosphate. In addition, another flame retardant, tri (1,3 dichloro-2-propyl) phosphate was also found. Because these contaminants have long column retention times in GLC, it may not be apparent that these contaminants are present and consequently are likely to have modified the sorbent characteristics of the activated charcoal. Another batch of sorbent tubes bearing the same catalog number and lot number was purchased from the supplier; no flame retardants were found in this batch.

  8. Tracheostomy tube - speaking

    MedlinePlus

    Air passing through vocal cords (larynx) causes them to vibrate, creating sounds and speech. A tracheostomy tube blocks most of the air from passing through your vocal cords. Instead, your breath (air) goes out ...

  9. Experimental and numerical investigation on air-side performance of fin-and-tube heat exchangers with various fin patterns

    SciTech Connect

    Tang, L.H.; Zeng, M.; Wang, Q.W.

    2009-07-15

    Air-side heat transfer and friction characteristics of five kinds of fin-and-tube heat exchangers, with the number of tube rows (N = 12) and the diameter of tubes (D{sub o} = 18 mm), have been experimentally investigated. The test samples consist of five types of fin configurations: crimped spiral fin, plain fin, slit fin, fin with delta-wing longitudinal vortex generators (VGs) and mixed fin with front 6-row vortex-generator fin and rear 6-row slit fin. The heat transfer and friction factor correlations for different types of heat exchangers were obtained with the Reynolds numbers ranging from 4000 to 10000. It was found that crimped spiral fin provides higher heat transfer and pressure drop than the other four fins. The air-side performance of heat exchangers with the above five fins has been evaluated under three sets of criteria and it was shown that the heat exchanger with mixed fin (front vortex-generator fin and rear slit fin) has better performance than that with fin with delta-wing vortex generators, and the slit fin offers best heat transfer performance at high Reynolds numbers. Based on the correlations of numerical data, Genetic Algorithm optimization was carried out, and the optimization results indicated that the increase of VG attack angle or length, or decrease of VG height may enhance the performance of vortex-generator fin. The heat transfer performances for optimized vortex-generator fin and slit fin at hand have been compared with numerical method. (author)

  10. AN ASSESSMENT OF THE STATE OF THE ART, AND POTENTIAL DESIGN IMPROVEMENTS, FOR FLAT-TUBE HEAT EXCHANGERS IN AIR CONDITIONING AND REFRIGERATION APPLICATIONS - PHASE I

    SciTech Connect

    Jacobi, A.M.; Park, Y.; Tafti, D.; Zhang, X.

    2001-09-30

    Project objective is to evaluate the air-side heat transfer and pressure-drop performance of serpentine-fin, flat-tube heat exchangers. This assessment is conducted for smooth, corrugated, and interrupted fins, over a wide range of geometric and operating parameters, spanning HVAC and R applications. The performance of serpentine-fin, flat-tube exchangers is compared to that of conventional round-tube designs, which are considered the technology baseline. The research includes a literature review, a preliminary comparison of flat-tube to round-tube performance, a computational fluid dynamic study of flow through the heat exchangers, and complementary modeling to predict the performance of flat-tube designs over a wide range of conditions. Recommendations are provided for a new experimental study to provide performance data for dry, wet, and frosted-surface conditions. Specific flow visualization and naphthalene sublimation experiments are recommended to understand the flow and heat transfer interactions in the flat-tube geometry. These data could be used to evaluate condensate retention and frost-formation effects on flat-tube heat exchanger performance, and to compare this behavior to that of the conventional round-tube geometry. These findings will be highly valuable to design and development engineers as they work toward the next generation of highly compact, energy efficient HVAC and R systems.

  11. Experimental Investigation of Average Heat-Transfer and Friction Coefficients for Air Flowing in Circular Tubes Having Square-Thread-Type Roughness

    NASA Technical Reports Server (NTRS)

    Sams, E. W.

    1952-01-01

    An investigation of forced-convection heat transfer and associated pressure drops was conducted with air flowing through electrically heated Inconel tubes having various degrees of square-thread-type roughness, an inside diameter of 1/2 inch, and a length of 24 inches. were obtained for tubes having conventional roughness ratios (height of thread/radius of tube) of 0 (smooth tube), 0.016, 0.025, and 0.037 over ranges of bulk Reynolds numbers up to 350,000, average inside-tube-wall temperatures up to 1950deg R, and heat-flux densities up to 115,000 Btu per hour per square foot. Data The experimental data showed that both heat transfer and friction increased with increase in surface roughness, becoming more pronounced with increase in Reynolds number; for a given roughness, both heat transfer and friction were also influenced by the tube wall-to-bulk temperature ratio. Good correlation of the heat-transfer data for all the tubes investigated was obtained by use of a modification of the conventional Nusselt correlation parameters wherein the mass velocity in the Reynolds number was replaced by the product of air density evaluated at the average film temperature and the so-called friction velocity; in addition, the physical properties of air were evaluated at the average film temperature. The isothermal friction data for the rough tubes, when plotted in the conventional manner, resulted in curves similar to those obtained by other investigators; that is, the curve for a given roughness breaks away from the Blasius line (representing turbulent flow in smooth tubes) at some value of Reynolds number, which decreases with increase in surface roughness, and then becomes a horizontal line (friction coefficient independent of Reynolds number). A comparison of the friction data for the rough tubes used herein indicated that the conventional roughness ratio is not an adequate measure of relative roughness for tubes having a square-thread-type element. The present data, as well

  12. Memory effects on adsorption tubes for mercury vapor measurement in ambient air: elucidation, quantification, and strategies for mitigation of analytical bias.

    PubMed

    Brown, Richard J C; Kumar, Yarshini; Brown, Andrew S; Kim, Ki-Hyun

    2011-09-15

    The short- and long-term memory effects associated with measurements of mercury vapor in air using gold-coated silica adsorption tubes have been described. Data are presented to quantify these effects and to determine their dependence on certain relevant measurement parameters, such as number of heating cycles used for each analysis, age of adsorption tube, mass of mercury on adsorption tube, and the length of time between analyses. The results suggest that the long-term memory effect is due to absorption of mercury within the bulk gold in the adsorption tube, which may only be fully liberated by allowing enough time for this mercury to diffuse to the gold surface. The implications of these effects for air quality networks making these measurements routinely has been discussed, and recommendations have been made to ensure any measurement bias is minimized.

  13. A vacuum tube vee-trough collector for solar heating and air conditioning applications

    NASA Technical Reports Server (NTRS)

    Selcuk, M. K.

    1978-01-01

    An analysis is conducted of the performance of a vee-trough vacuum tube collector proposed for use in solar heating and cooling applications. The vee-trough reflector is a triangular sectioned, flat surfaced reflector, whose axis is laid in the East-West direction. A vacuum tube receiver placed at the bottom of the vee-trough collects solar heat most efficiently since convection is completely eliminated. Radiation losses are reduced by use of selective coatings on the absorber. Owing to its high temperature capabilities (300-400 F), the proposed scheme could also be used for power generation applications in combination with an organic Rankine conversion system. It is especially recommended for unattended pumping stations since the reflectors only require reversal once every six months.

  14. Air sampling of flame retardants based on the use of mixed-bed sorption tubes--a validation study.

    PubMed

    Lazarov, Borislav; Swinnen, Rudi; Spruyt, Maarten; Maes, Frederick; Van Campenhout, Karen; Goelen, Eddy; Covaci, Adrian; Stranger, Marianne

    2015-11-01

    An analytical methodology using automatic thermal desorption and gas chromatography mass spectrometry analysis was optimized and validated for simultaneous determination of a set of components from three different flame retardant chemical classes: polybrominated diphenyl ethers (PBDEs) (PBDE-28, PBDE-47, PBDE-66, PBDE-85, PBDE-99, PBDE-100), organophosphate flame retardants (PFRs) (tributyl phosphate, tripropyl phosphate, tris(2-chloroethyl)phosphate-, tris(1,3-dichloro-2-propyl) phosphate, tris(2-ethylhexyl) phosphate, triphenyl phosphate, tris(2-chloro-1-methylethyl) phosphate and tricresylphosphate), and "novel" brominated flame retardants (NBFRs) (pentabromotoluene, 2,3,4,5,6-pentabromoethylbenzene, (2,3-dibromopropyl) (2,4,6-tribromophenyl) ether, hexabromobenzene, and 2-ethylhexyl 2,3,4,5-tetrabromobenzoate) in air. The methodology is based on low volume active air sampling of gaseous and particulate air fractions on mixed-bed (polydimethylsiloxane (PDMS)/Tenax TA) sorption tubes. The optimized method provides recoveries >88%; a limit of detection in the range of 6-25 pg m(-3) for PBDEs, 6-171 pg m(-3) for PFRs, and 7-41 pg m(-3) for NBFRs; a linearity greater than 0.996; and a repeatability of less than 10% for all studied compounds. The optimized method was compared with a standard method using active air sampling on XAD-2 sorbent material, followed by liquid extraction. On the one hand, the PDMS/Tenax TA method shows comparable results at longer sampling time conditions (e.g., indoor air sampling, personal air sampling). On the other hand, at shorter sampling time conditions (e.g., sampling from emission test chambers), the optimized method detects up to three times higher concentrations and identifies more flame retardant compounds compared to the standard method based on XAD-2 loading.

  15. Selected Ion Flow-Drift Tube Mass Spectrometry: Quantification of Volatile Compounds in Air and Breath.

    PubMed

    Spesyvyi, Anatolii; Smith, David; Španěl, Patrik

    2015-12-15

    A selected ion flow-drift tube mass spectrometric analytical technique, SIFDT-MS, is described that extends the established selected ion flow tube mass spectrometry, SIFT-MS, by the inclusion of a static but variable E-field along the axis of the flow tube reactor in which the analytical ion-molecule chemistry occurs. The ion axial speed is increased in proportion to the reduced field strength E/N (N is the carrier gas number density), and the residence/reaction time, t, which is measured by Hadamard transform multiplexing, is correspondingly reduced. To ensure a proper understanding of the physics and ion chemistry underlying SIFDT-MS, ion diffusive loss to the walls of the flow-drift tube and the mobility of injected H3O(+) ions have been studied as a function of E/N. It is seen that the derived diffusion coefficient and mobility of H3O(+) ions are consistent with those previously reported. The rate coefficient has been determined at elevated E/N for the association reaction of the H3O(+) reagent ions with H2O molecules, which is the first step in the production of H3O(+)(H2O)1,2,3 reagent hydrate ions. The production of hydrated analyte ion was also experimentally investigated. The analytical performance of SIFDT-MS is demonstrated by the quantification of acetone and isoprene in exhaled breath. Finally, the essential features of SIFDT-MS and SIFT-MS are compared, notably pointing out that a much lower speed of the flow-drive pump is required for SIFDT-MS, which facilitates the development of smaller cost-effective analytical instruments for real time breath and fluid headspace analyses.

  16. The combined effects of sampling parameters on the sorbent tube sampling of phthalates in air

    PubMed Central

    Jo, Sang-Hee; Kim, Ki-Hyun; Kwon, Kyenghee

    2017-01-01

    The adsorption properties of various sorbent materials were investigated to assess the factors affecting biases in the sorbent tube (ST) sampling of airborne phthalates. The recovery of phthalates was assessed critically in relation to four key sampling parameters: (1) three types of sorbent materials (quartz wool (QW), glass wool (GW), and quartz wool plus Tenax TA (QWTN)), (2) the concentration level of phthalate standards, (3) purge flow rate, and (4) purge volume for analysis based on a ‘sorbent tube-thermal desorption-gas chromatography-mass spectrometry (ST-TD-GC-MS)’ system. Among these parameters, the type of ST was the most influential in determining the recovery of phthalates. For a given ST type, the recovery of phthalates tends to improve with increases in the concentration level of standards. In case of QW and QWTN tubes, the breakthrough of phthalates was not observed up to the maximum purge volume (100 L) tested in this work; however, in case of GW, the recovery decreased drastically to 60% even at a purge volume of 1 L for low molecular weight phthalates. The results of our study demonstrate that accurate analysis of airborne phthalates can be achieved through proper control of key sampling parameters, particularly the choice of sorbent material. PMID:28361993

  17. Comparison of electrode reduction activities of Geobacter sulfurreducens and an enriched consortium in an air-cathode microbial fuel cell.

    PubMed

    Ishii, Shun'ichi; Watanabe, Kazuya; Yabuki, Soichi; Logan, Bruce E; Sekiguchi, Yuji

    2008-12-01

    An electricity-generating bacterium, Geobacter sulfurreducens PCA, was inoculated into a single-chamber, air-cathode microbial fuel cell (MFC) in order to determine the maximum electron transfer rate from bacteria to the anode. To create anodic reaction-limiting conditions, where electron transfer from bacteria to the anode is the rate-limiting step, anodes with electrogenic biofilms were reduced in size and tests were conducted using anodes of six different sizes. The smallest anode (7 cm(2), or 1.5 times larger than the cathode) achieved an anodic reaction-limiting condition as a result of a limited mass of bacteria on the electrode. Under these conditions, the limiting current density reached a maximum of 1,530 mA/m(2), and power density reached a maximum of 461 mW/m(2). Per-biomass efficiency of the electron transfer rate was constant at 32 fmol cell(-1) day(-1) (178 micromol g of protein(-1) min(-1)), a rate comparable to that with solid iron as the electron acceptor but lower than rates achieved with fumarate or soluble iron. In comparison, an enriched electricity-generating consortium reached 374 micromol g of protein(-1) min(-1) under the same conditions, suggesting that the consortium had a much greater capacity for electrode reduction. These results demonstrate that per-biomass electrode reduction rates (calculated by current density and biomass density on the anode) can be used to help make better comparisons of electrogenic activity in MFCs.

  18. Preliminary study on zinc-air battery using zinc regeneration electrolysis with propanol oxidation as a counter electrode reaction

    NASA Astrophysics Data System (ADS)

    Wen, Yue-Hua; Cheng, Jie; Ning, Shang-Qi; Yang, Yu-Sheng

    A zinc-air battery using zinc regeneration electrolysis with propanol oxidation as a counter electrode reaction is reported in this paper. It possesses functions of both zincate reduction and electrochemical preparation, showing the potential for increasing the electronic energy utilization. Charge/discharge tests and scanning electron microscopy (SEM) micrographs reveal that when a nickel sheet plated with the high-H 2-overpotential metal, cadmium, was used as the negative substrate electrode, the dendritic formation and hydrogen evolution are suppressed effectively, and granular zinc deposits become larger but relatively dense with the increase of charge time. The performance of batteries is favorable even if the charge time is as long as 5 h at the current density of 20 mA cm -2. Better discharge performance is achieved using a 'cavity-opening' configuration for the discharge cell rather than a 'gas-introducing' configuration. The highest energy efficiency is up to 59.2%. That is, the energy consumed by organic electro-synthesis can be recovered by 59.2%. Cyclic voltammograms show that the sintered nickel electrode exhibits a good electro-catalysis activity for the propanol oxidation. The increase of propanol concentration conduces to an enhancement in the organic electro-synthesis efficiency. The organic electro-synthesis current efficiency of 82% can be obtained.

  19. Heat tube device

    NASA Technical Reports Server (NTRS)

    Khattar, Mukesh K. (Inventor)

    1990-01-01

    The present invention discloses a heat tube device through which a working fluid can be circulated to transfer heat to air in a conventional air conditioning system. The heat tube device is disposable about a conventional cooling coil of the air conditioning system and includes a plurality of substantially U-shaped tubes connected to a support structure. The support structure includes members for allowing the heat tube device to be readily positioned about the cooling coil. An actuatable adjustment device is connected to the U-shaped tubes for allowing, upon actuation thereof, for the heat tubes to be simultaneously rotated relative to the cooling coil for allowing the heat transfer from the heat tube device to air in the air conditioning system to be selectively varied.

  20. Influence of air flow parameters on nanosecond repetitively pulsed discharges in a pin-annular electrode configuration

    NASA Astrophysics Data System (ADS)

    Heitz, Sylvain A.; Moeck, Jonas P.; Schuller, Thierry; Veynante, Denis; Lacoste, Deanna A.

    2016-04-01

    The effect of various air flow parameters on the plasma regimes of nanosecond repetitively pulsed (NRP) discharges is investigated at atmospheric pressure. The two electrodes are in a pin-annular configuration, transverse to the mean flow. The voltage pulses have amplitudes up to 15 kV, a duration of 10 ns and a repetition frequency ranging from 15 to 30 kHz. The NRP corona to NRP spark (C-S) regime transition and the NRP spark to NRP corona (S-C) regime transition are investigated for different steady and harmonically oscillating flows. First, the strong effect of a transverse flow on the C-S and S-C transitions, as reported in previous studies, is verified. Second, it is shown that the azimuthal flow imparted by a swirler does not affect the regime transition voltages. Finally, the influence of low frequency harmonic oscillations of the air flow, generated by a loudspeaker, is studied. A strong effect of frequency and amplitude of the incoming flow modulation on the NRP plasma regime is observed. Results are interpreted based on the cumulative effect of the NRP discharges and an analysis of the residence times of fluid particles in the inter-electrode region.

  1. High performance air electrode for solid oxide regenerative fuel cells fabricated by infiltration of nano-catalysts

    NASA Astrophysics Data System (ADS)

    Lee, Sung-il; Kim, Jeonghee; Son, Ji-Won; Lee, Jong-Ho; Kim, Byung-Kook; Je, Hae-June; Lee, Hae-Weon; Song, Huesup; Yoon, Kyung Joong

    2014-03-01

    A high performance air electrode fabricated by infiltration of highly active nano-catalysts into a porous scaffold is demonstrated for high-temperature solid oxide regenerative fuel cells (SORFCs). The nitrate precursor solution for Sm0.5Sr0.5CoO3 (SSC) catalyst is impregnated into a porous La0.6Sr0.4Co0.2Fe0.8O3 (LSCF)-gadolinia-doped ceria (GDC) composite backbone, and extremely fine SSC nano-particles are uniformly synthesized by in-situ crystallization at the initial stage of SORFC operation via homogeneous nucleation induced by urea decomposition. The SSC nano-catalysts are in the size range of 40-80 nm and stable against coarsening upon the SORFC operation at 750 °C. The electrochemical performance is significantly improved by incorporation of SSC nano-catalysts in both power generation and hydrogen production modes. Systematic analysis on the impedance spectra reveals that the surface modification of the air electrode with nano-catalysts remarkably accelerates the chemical surface exchange reactions for both O2 reduction and O2- oxidation, which are the major limiting processes for SORFC performance.

  2. The Role of Air-Electrode Structure on the Incorporation of Immiscible PFCs in Nonaqueous Li-O2 Battery.

    PubMed

    Balaish, Moran; Ein-Eli, Yair

    2017-03-22

    Perfluorocarbons (PFCs) are considered advantageous additives to nonaqueous Li-O2 battery due to their superior oxygen solubility and diffusivity compared to common battery electrolytes. Up to now, the main focus was concentrated on PFCs-electrolyte investigation; however, no special attention was granted to the role of carbon structure in the PFCs-Li-O2 system. In our current research, immiscible PFCs, rather than miscible fluorinated ethers, were added to activated carbon class air electrode due to their higher susceptibility toward O2(•-) attack and to their ability to shift the reaction from two-phase to an artificial three-phase reaction zone. The results showed superior battery performance upon PFCs addition at lower current density (0.05 mA cm(-2)) but unexpectedly failed to do so at higher current density (0.1 and 0.2 mA cm(-2)), where oxygen transport limitation is best illustrated. The last was a direct result of liquid-liquid displacement phenomenon occurring when the two immiscible liquids were introduced into the porous carbon medium. The investigation and role of carbon structure on the mechanism upon PFCs addition to Li-O2 system are suggested based on electrochemical characterization, wettability behavior studies, and the physical adsorption technique. Finally, we suggest an optimum air-electrode structure enabling the incorporation of immiscible PFCs in a nonaqueous Li-O2 battery.

  3. Graphene Oxide Involved Air-Controlled Electrospray for Uniform, Fast, Instantly Dry, and Binder-Free Electrode Fabrication.

    PubMed

    Fei, Ling; Yoo, Sang Ha; Villamayor, Rachel Ann R; Williams, Brian P; Gong, Seon Young; Park, Sunchan; Shin, Kyusoon; Joo, Yong Lak

    2017-03-22

    We report a facile air-controlled electrospray method to directly deposit binder-free active materials/graphene oxide (GO) onto current collectors. This method is inspired from an electrospinning process, and possesses all the advantages that electrospinning has such as low cost, easy scaling up, and simultaneous solvent evaporation during the spraying process. Moreover, the spray slurry is only a simple mixture of active materials and GO suspension in water, no binder polymer, organic solvent, and conductive carbon required. In our research, high-capacity Si nanoparticles (Si NP, 70-100 nm) and SiO microparticles (SiO MP, 3-10 μm) were selected to demonstrate the capability of this method to accommodate particles with different sizes. Their mixture with GO was sprayed onto a collector and then thermally annealed in an inert gas to obtain Si NP or SiO MP/reduced graphene oxide (RGO) binder-free electrodes. We are also able to directly deposit fairly large electrode sheets (e.g., 12 × 21 in.) upon the application requirement. To the best of our knowledge, this is the simplest approach to produce Si-related materials/RGO layered structures directly on current collector with controllable area and loading. Si and SiO MP/RGO are evaluated in both half and full lithium cells, showing good electrochemical performance. Prelithiation is also studied and gives a high first cycle Coulombic efficiency. In addition to Si-related materials, other materials with different shapes and sizes (e.g., MoO3 nanobelts, Sn/carbon nanofibers, and commercial sulfur particles) can also be sprayed. Beyond the preparation of battery electrodes, this approach can also be applied for other types of electrode preparation such as that of a supercapacitor, fuel cell, and solar cell.

  4. Determination of antimony, arsenic, bismuth, selenium, tellurium and tin by low pressure atomic absorption spectrometry with a quartz tube furnace atomizer and hydride generation with air addition.

    PubMed

    Zhang, B; Wang, Y; Wang, X; Chen, X; Feng, J

    1995-08-01

    A new method has been developed for the determination of antimony, arsenic, bismuth, selenium, tellurium and tin by hydride generation-atomic absorption spectrometry in an electrically heated quartz tube furnace under sub-atmospheric pressure. The hydride generator, operating at a pressure lower than atmospheric, is used to generate and collect the hydrides of these elements. A certain volume (at atmospheric pressure) of air is then added to the generator after the formation of the volatile hydride. The gaseous mixture of the hydride and air is drawn into an evacuated, heated quartz tube by a vacuum pump. The proposed method gives improved sensitivities and detection limits.

  5. Finned tube heat exchangers: state of the art for the air side

    SciTech Connect

    McQuiston, F. C.

    1980-01-01

    The findings of various investigators during the past ten years has greatly enhanced our ability to analyze, model, design, and optimize the finned tube heat exchangers so widely used in the HVAC business. The effect of rows, fin pitch, and other geometric parameters are now well understood and generalized heat transfer correlations are available. The relation between heat and mass transfer has been much better defined and good correlations have been developed. Some advances have also been made in modeling techniques especially where partially dry cooling and dehumidifying coils are involved. All of these factors are reviewed to concisely summarize what is now available to the heat exchanger analyst.

  6. A large-area diffuse air discharge plasma excited by nanosecond pulse under a double hexagon needle-array electrode.

    PubMed

    Liu, Zhi-Jie; Wang, Wen-Chun; Yang, De-Zheng; Wang, Sen; Zhang, Shuai; Tang, Kai; Jiang, Peng-Chao

    2014-01-01

    A large-area diffuse air discharge plasma excited by bipolar nanosecond pulse is generated under a double hexagon needle-array electrode at atmospheric pressure. The images of the diffuse discharge, electric characteristics, and the optical emission spectra emitted from the diffuse air discharge plasma are obtained. Based on the waveforms of pulse voltage and current, the power consumption, and the power density of the diffuse air discharge plasma are investigated under different pulse peak voltages. The electron density and the electron temperature of the diffuse plasma are estimated to be approximately 1.42×10(11) cm(-3) and 4.4 eV, respectively. The optical emission spectra are arranged to determine the rotational and vibrational temperatures by comparing experimental with simulated spectra. Meanwhile, the rotational and vibrational temperatures of the diffuse discharge plasma are also discussed under different pulse peak voltages and pulse repetition rates, respectively. In addition, the diffuse air discharge plasma can form an area of about 70×50 mm(2) on the surface of dielectric layer and can be scaled up to the required size.

  7. Fast fabrication of copper nanowire transparent electrodes by a high intensity pulsed light sintering technique in air.

    PubMed

    Ding, Su; Jiu, Jinting; Tian, Yanhong; Sugahara, Tohru; Nagao, Shijo; Suganuma, Katsuaki

    2015-12-14

    Copper nanowire transparent electrodes have received increasing interest due to the low price and nearly equal electrical conductivity compared with other TEs based on silver nanowires and indium tin oxide (ITO). However, a post-treatment at high temperature in an inert atmosphere or a vacuum environment was necessary to improve the conductivity of Cu NW TEs due to the easy oxidation of copper in air atmosphere, which greatly cancelled out the low price advantage of Cu NWs. Here, a high intensity pulsed light technique was introduced to sinter and simultaneously deoxygenate these Cu NWs into a highly conductive network at room temperature in air. The strong light absorption capacity of Cu NWs enabled the welding of the nanowires at contact spots, as well as the removal of the thin layer of residual organic compounds, oxides and hydroxide of copper even in air. The Cu NW TE with a sheet resistance of 22.9 Ohm sq(-1) and a transparency of 81.8% at 550 nm has been successfully fabricated within only 6 milliseconds exposure treatment, which is superior to other films treated at high temperature in a hydrogen atmosphere. The HIPL process was simple, convenient and fast to fabricate easily oxidized Cu NW TEs in large scale in an air atmosphere, which will largely extend the application of cheap Cu NW TEs.

  8. Silver nanoparticle-decorated carbon nanotubes as bifunctional gas-diffusion electrodes for zinc-air batteries

    NASA Astrophysics Data System (ADS)

    Wang, T.; Kaempgen, M.; Nopphawan, P.; Wee, G.; Mhaisalkar, S.; Srinivasan, M.

    Thin, lightweight, and flexible gas-diffusion electrodes (GDEs) based on freestanding entangled networks of single-walled carbon nanotubes (SWNTs) decorated with Ag nanoparticles (AgNPs) are tested as the air-breathing cathode in a zinc-air battery. The SWNT networks provide a highly porous surface for active oxygen absorption and diffusion. The high conductivity of SWNTs coupled with the catalytic activity of AgNPs for oxygen reduction leads to an improvement in the performance of the zinc-air cell. By modulating the pH value and the reaction time, different sizes of AgNPs are decorated uniformly on the SWNTs, as revealed by transmission electron microscopy and powder X-ray diffraction. AgNPs with sizes of 3-5 nm double the capacity and specific energy of a zinc-air battery as compared with bare SWNTs. The simplified, lightweight architecture shows significant advantages over conventional carbon-based GDEs in terms of weight, thickness and conductivity, and hence may be useful for mobile and portable applications.

  9. Significance of High-Speed Air Temperature Measurements in the Sampling Cell of a Closed-Path Gas Analyzer with a Short Tube

    NASA Astrophysics Data System (ADS)

    Kathilankal, James; Fratini, Gerardo; Burba, George

    2015-04-01

    Eddy covariance gas analyzers measure gas content in a known volume, thus essentially measuring gas density. The fundamental flux equation, however, is based on the dry mole fraction. The relationship between dry mole fraction and density is regulated by the ideal gas law describing the processes of temperature- and pressure-related expansions and contractions, and by the law of partial pressures, describing the process of dilution. As a result, this relationship depends on water vapor content, temperature and pressure of the air sample. If the instrument is able to output precise high-speed dry mole fraction, the flux processing is significantly simplified and WPL density terms accounting for the air density fluctuations are no longer required. This should also lead to the reduction in uncertainties associated with the density terms resulting from the eddy covariance measurements of sensible and latent heat fluxes used in these terms. In this framework, three main measurement approaches may be considered: Open-path approach Outputting correct high-speed dry mole fraction from the open-path instrument is difficult because of complexities with maintaining reliable fast temperature measurements integrated over the entire measuring path, and also because of extraordinary challenges with accurate measurements of fast pressure in the open air flow. Classical long-tube closed-path approach For instruments utilizing traditional long-tube closed-path design, with tube length 1000 or more times the tube diameter, the fast dry mole fraction can be used successfully when instantaneous fluctuations in the air temperature of the sampled air are effectively dampened to negligible levels, instantaneous pressure fluctuations are regulated or negligible, and water vapor is measured simultaneously with gas or the air sample is dried. Short-tube closed-path approach, the enclosed design For instruments with a short-tube enclosed design, most - but not all - of the temperature

  10. The tubular MFC with carbon tube air-cathode for power generation and N,N-dimethylacetamide treatment.

    PubMed

    Liu, Jiadong; Liu, Lifen; Gao, Bo

    2016-01-01

    A continuous flow microbial fuel cell (MFC) was assembled with carbon tube air-cathode and carbon felt anode. The organic solvent N,N-dimethylacetamide (DMAC) was used as the only carbon source for power generation. After the adaptive phase, the cell potential was gradually increased from 0.15 to 0.45 V with 200 Ω of external resistor during 150 h of operation. The calculated power density of this MFC was 100 mW L(-1) when the cell potential was 0.45 V. The reversible redox peaks of carbon tube were obtained in cyclic voltammogram between -0.5 and -0.25 V under aerobic circumstance. The removal rate of DMAC was 15-50% after treatment with hydraulic retention time of 12 min. The results indicated that it is possible to realize the power extraction from DMAC wastewater in the form of electricity by the bioconversion process of MFC.

  11. Prediction of hydrodynamics and chemistry of confined turbulent methane-air frames in a two concentric tube combustor

    NASA Technical Reports Server (NTRS)

    Markatos, N. C.; Spalding, D. B.; Srivatsa, S. K.

    1978-01-01

    A formulation of the governing partial differential equations for fluid flow and reacting chemical species in a two-concentric-tube combustor is presented. A numerical procedure for the solution of the governing differential equations is described and models for chemical-equilibrium and chemical-kinetics calculations are presented. The chemical-equilibrium model is used to characterize the hydrocarbon reactions. The chemical-kinetics model is used to predict the concentrations of the oxides of nitrogen. The combustor considered consists of two coaxial ducts. Concentric streams of gaseous fuel and air enter the inlet duct at one end; the flow then reverses and flows out through the outer duct. Two sample cases with specified inlet and boundary conditions are considered and the results are discussed.

  12. Scanning drift tube measurements of electron transport parameters in different gases: argon, synthetic air, methane and deuterium

    NASA Astrophysics Data System (ADS)

    Korolov, I.; Vass, M.; Donkó, Z.

    2016-10-01

    Measurements of transport coefficients of electrons in a scanning drift tube apparatus are reported for different gases: argon, synthetic air, methane and deuterium. The experimental system allows the spatio-temporal development of the electron swarms (‘swarm maps’) to be recorded and this information, when compared with the profiles predicted by theory, makes it possible to determine the ‘time-of-flight’ transport coefficients: the bulk drift velocity, the longitudinal diffusion coefficient and the effective ionization coefficient, in a well-defined way. From these data, the effective Townsend ionization coefficient is determined as well. The swarm maps provide, additionally, direct, unambiguous information about the hydrodynamic/non-hydrodynamic regimes of the swarms, aiding the selection of the proper regions applicable for the determination of the transport coefficients.

  13. Combined hydrolysis acidification and bio-contact oxidation system with air-lift tubes and activated carbon bioreactor for oilfield wastewater treatment.

    PubMed

    Guo, Chunmei; Chen, Yi; Chen, Jinfu; Wang, Xiaojun; Zhang, Guangqing; Wang, Jingxiu; Cui, Wenfeng; Zhang, Zhongzhi

    2014-10-01

    This paper investigated the enhancement of the COD reduction of an oilfield wastewater treatment process by installing air-lift tubes and adding an activated carbon bioreactor (ACB) to form a combined hydrolysis acidification and bio-contact oxidation system with air-lift tubes (HA/air-lift BCO) and an ACB. Three heat-resistant bacterial strains were cultivated and subsequently applied in above pilot plant test. Installing air-lift tubes in aerobic tanks reduced the necessary air to water ratio from 20 to 5. Continuous operation of the HA/air-lift BCO system for 2 months with a hydraulic retention time of 36 h, a volumetric load of 0.14 kg COD/(m(3)d) (hydrolysis-acidification or anaerobic tank), and 0.06 kg COD/(m(3)d) (aerobic tanks) achieved an average reduction of COD by 60%, oil and grease by 62%, total suspended solids by 75%, and sulfides by 77%. With a COD load of 0.56 kg/(m(3)d), the average COD in the ACB effluent was 58 mg/L.

  14. Air quality inside a tunnel tube and in the vicinity of the tunnel portals

    SciTech Connect

    Pucher, K.; Zwiener, K.

    1997-12-31

    Due to the continually growing number of motor vehicles more and more roads are reaching the limits of their capability. This has led to slowly moving traffic and longer persisting traffic blockages. In cities and conurbation centers especially this leads to complete traffic chaos. The pollutant emissions of vehicles that only move very little mostly lead to high pollutant burdens also and in some circumstances to poor air quality. Therefore in more and more cities one is attempting to get traffic moving again through efficient road tunnels and underground lines and thereby also reduce the pollutant emission. Typical examples of such developments are the Central Artery Tunnel Project in Boston, the planned Ringroad tunnel in Stockholm and the Ringtunnel projects in Paris. Tunnel constructions and underground lines in densely built-up areas are also planned in many small cities. For all these tunnel projects the following points concerning the air quality are to be observed. On the one hand, a tunnel construction can accommodate traffic and thereby reduce the traffic blockages in the vicinity of the tunnel, so long as no additional traffic is attracted. This would therefore lead to a reduction of the pollutant burden and also to an improvement in the air quality in large areas of further surroundings of the tunnel construction. On the other hand, at the portals of the tunnel, alongside mobile pollutant sources from vehicles travelling on the already existing road, a stationary pollutant source of the tunnel ventilation flowing out from the tunnel portal also results. It is then to be investigated how high the emerging pollutant concentrations will be at the portal of the planned tunnel and how these pollutants will disseminate. In this report therefore, the air quality in the tunnel as well as in the vicinity of the tunnel portals will be more closely dealt with.

  15. A new certified reference material for benzene measurement in air on a sorbent tube: development and proficiency testing.

    PubMed

    Caurant, A; Lalère, B; Schbath, M-C; Stumpf, C; Sutour, C; Mace, T; Quisefit, J-P; Doussin, J-F; Vaslin-Reimann, S

    2010-11-01

    A certified matrix reference material (CRM) for the measurement of benzene in ambient air has been developed at Laboratoire National de Métrologie et d'Essais. The production of these CRMs was conducted using a gravimetric method fully traceable to the International System of Units. The CRMs were prepared by sampling an accurate mass of a gaseous primary reference material of benzene, using a high-precision laminar flowmeter and a mass flow controller, with a PerkinElmer sampler filled with Carbopack™ X sorbent. The relative standard deviations obtained for the preparation of a batch of 20 tubes loaded with 500 ng of benzene were below 0.2%. Each CRM is considered independent from the others and with its own certified value and an expanded uncertainty estimated to be within 0.5%, lower than the uncertainties of benzene CRMs already available worldwide. The stability of these materials was also established up to 12 months. These CRMs were implemented during proficiency testing, to evaluate the analytical performances of seven French laboratories involved in benzene air monitoring.

  16. Hydrogen peroxide detection in wet air with a Prussian Blue based solid salt bridged three electrode system.

    PubMed

    Komkova, Maria A; Karyakina, Elena E; Marken, Frank; Karyakin, Arkady A

    2013-03-05

    We report on a novel electroanalytical system for hydrogen peroxide (H2O2) detection in humidity or droplets of aerosol, formed by air bubbling through a washing chamber; the resulting flow mimics the exhaled human breath. The system is based on a planar three-electrode structure (with a Prussian Blue based H2O2 transducer modified working electrode) bridged by a solid salt-saturated filament material (filter paper, cotton textile). Respective to the hydrogen peroxide content in the washing valve, the response of the aerosol-sensing system is linear in the concentration range of 0.1-10 μM, which overlaps the generally accepted H2O2 content in exhaled breath condensate (EBC), with the sensitivity of 8 A M(-1) cm(-2). The response to the upper limit of the calibration range is stable for more than 50 injection cycles recorded within 3 days. Both the stability and the suitable calibration range allow one to consider the reported aerosol-sensing system as a prototype for a simple (avoiding intermediate EBC collection) noninvasive diagnostic tool for pulmonary patients.

  17. A Comparison of EAST Shock-Tube Radiation Measurements with a New Air Radiation Model

    NASA Technical Reports Server (NTRS)

    Johnston, Christopher O.

    2008-01-01

    This paper presents a comparison between the recent EAST shock tube radiation measurements (Grinstead et al., AIAA 2008-1244) and the HARA radiation model. The equilibrium and nonequilibrium radiation measurements are studied for conditions relevant to lunar-return shock-layers; specifically shock velocities ranging from 9 to 11 kilometers per second at initial pressures of 0.1 and 0.3 Torr. The simulated shock-tube flow is assumed one-dimensional and is calculated using the LAURA code, while a detailed nonequilibrium radiation prediction is obtained in an uncoupled manner from the HARA code. The measured and predicted intensities are separated into several spectral ranges to isolate significant spectral features, mainly strong atomic line multiplets. The equations and physical data required for the prediction of these strong atomic lines are reviewed and their uncertainties identified. The 700-1020 nm wavelength range, which accounts for roughly 30% of the radiative flux to a peak-heating lunar return shock-layer, is studied in detail and the measurements and predictions are shown to agree within 15% in equilibrium. The plus or minus 1.5% uncertainty on the measured shock velocity is shown to cause up to a plus or minus 30% difference in the predicted radiation. This band of predictions contains the measured values in almost all cases. For the highly nonequilibrium 0.1 Torr cases, the nonequilibrium radiation peaks are under-predicted by about half. This under-prediction is considered acceptable when compared to the order-of-magnitude over-prediction obtained using a Boltzmann population of electronic states. The reasonable comparison in the nonequilibrium regions provides validation for both the non-Boltzmann modeling in HARA and the thermochemical nonequilibrium modeling in LAURA. The N2 (+)(1-) and N2(2+) molecular band systems are studied in the 290 480 nm wavelength range for both equilibrium and nonequilibrium regimes. The non-Boltzmann rate models for these

  18. Iron-Air Rechargeable Battery

    NASA Technical Reports Server (NTRS)

    Narayan, Sri R. (Inventor); Prakash, G.K. Surya (Inventor); Kindler, Andrew (Inventor)

    2014-01-01

    Embodiments include an iron-air rechargeable battery having a composite electrode including an iron electrode and a hydrogen electrode integrated therewith. An air electrode is spaced from the iron electrode and an electrolyte is provided in contact with the air electrode and the iron electrodes. Various additives and catalysts are disclosed with respect to the iron electrode, air electrode, and electrolyte for increasing battery efficiency and cycle life.

  19. Generation of large-scale, barrier-free diffuse plasmas in air at atmospheric pressure using array wire electrodes and nanosecond high-voltage pulses

    SciTech Connect

    Teng, Yun; Li, Lee Liu, Yun-Long; Liu, Lun; Liu, Minghai

    2014-10-15

    This paper introduces a method to generate large-scale diffuse plasmas by using a repetition nanosecond pulse generator and a parallel array wire-electrode configuration. We investigated barrier-free diffuse plasmas produced in the open air in parallel and cross-parallel array line-line electrode configurations. We found that, when the distance between the wire-electrode pair is small, the discharges were almost extinguished. Also, glow-like diffuse plasmas with little discharge weakening were obtained in an appropriate range of line-line distances and with a cathode-grounding cross-electrode configuration. As an example, we produced a large-scale, stable diffuse plasma with volumes as large as 18 × 15 × 15 cm{sup 3}, and this discharge region can be further expanded. Additionally, using optical and electrical measurements, we showed that the electron temperature was higher than the gas temperature, which was almost the same as room temperature. Also, an array of electrode configuration with more wire electrodes had helped to prevent the transition from diffuse discharge to arc discharge. Comparing the current waveforms of configurations with 1 cell and 9 cells, we found that adding cells significantly increased the conduction current and the electrical energy delivered in the electrode gaps.

  20. Generation of large-scale, barrier-free diffuse plasmas in air at atmospheric pressure using array wire electrodes and nanosecond high-voltage pulses

    NASA Astrophysics Data System (ADS)

    Teng, Yun; Li, Lee; Liu, Yun-Long; Liu, Lun; Liu, Minghai

    2014-10-01

    This paper introduces a method to generate large-scale diffuse plasmas by using a repetition nanosecond pulse generator and a parallel array wire-electrode configuration. We investigated barrier-free diffuse plasmas produced in the open air in parallel and cross-parallel array line-line electrode configurations. We found that, when the distance between the wire-electrode pair is small, the discharges were almost extinguished. Also, glow-like diffuse plasmas with little discharge weakening were obtained in an appropriate range of line-line distances and with a cathode-grounding cross-electrode configuration. As an example, we produced a large-scale, stable diffuse plasma with volumes as large as 18 × 15 × 15 cm3, and this discharge region can be further expanded. Additionally, using optical and electrical measurements, we showed that the electron temperature was higher than the gas temperature, which was almost the same as room temperature. Also, an array of electrode configuration with more wire electrodes had helped to prevent the transition from diffuse discharge to arc discharge. Comparing the current waveforms of configurations with 1 cell and 9 cells, we found that adding cells significantly increased the conduction current and the electrical energy delivered in the electrode gaps.

  1. Superheater/intermediate temperature air heater tube corrosion tests in the MHD coal fired flow facility (Montana Rosebud POC tests)

    SciTech Connect

    White, M.

    1996-01-01

    Nineteen alloys have been exposed for approximately 1000 test hours as candidate superheater and intermediate temperature air heater tubes in a U.S. DOE facility dedicated to demonstrating Proof of Concept for the bottoming or heat and seed recovery portion of coal fired magnetohydrodynamic (MHD) electrical power generating plants. Corrosion data have been obtained from a test series utilizing a western United States sub-bituminous coal, Montana Rosebud. The test alloys included a broad range of compositions ranging from carbon steel to austenitic stainless steels to high chromium nickel-base alloys. The tubes, coated with K{sub 2}SO-containing deposits, developed principally, oxide scales by an oxidation/sulfidation mechanism. In addition to being generally porous, these scales were frequently spalled and/or non-compact due to a dispersed form of outward growth by oxide precipitation in the adjacent deposit. Austenitic alloys generally had internal penetration as trans Tranular and/or intergranular oxides and sulfides. While only two of the alloys had damage visible without magnification as a result of the relatively short exposure, there was some concern about Iona-term corrosion performance owing to the relatively poor quality scales formed. Comparison of data from these tests to those from a prior series of tests with Illinois No. 6, a high sulfur bituminous coal, showed less corrosion in the present test series with the lower sulfur coal. Although K{sub 2}SO{sub 4}was the principal corrosive agent as the supplier of sulfur, which acted to degrade alloy surface scales, tying up sulfur as K{sub 2}SO{sub 4} prevented the occurrence of complex alkali iron trisulfates responsible for severe or catastrophic corrosion in conventional power plants with certain coals and metal temperatures.

  2. Measurements of average heat-transfer and friction coefficients for subsonic flow of air in smooth tubes at high surface and fluid temperatures

    NASA Technical Reports Server (NTRS)

    Humble, Leroy V; Lowdermilk, Warren H; Desmon, Leland G

    1951-01-01

    An investigation of forced-convection heat transfer and associated pressure drops was conducted with air flowing through smooth tubes for an over-all range of surface temperature from 535 degrees to 3050 degrees r, inlet-air temperature from 535 degrees to 1500 degrees r, Reynolds number up to 500,000, exit Mach number up to 1, heat flux up to 150,000 btu per hour per square foot, length-diameter ratio from 30 to 120, and three entrance configurations. Most of the data are for heat addition to the air; a few results are included for cooling of the air. The over-all range of surface-to-air temperature ratio was from 0.46 to 3.5.

  3. Impact of air and refrigerant maldistributions on the performance of finned-tube evaporators with R-22 and R-407C. Final Report

    SciTech Connect

    Lee, Jangho; Domanski, P.A.

    1997-07-01

    The report presents basic features of the evaporator model, EVAP5M, and simulation results for an evaporator operating with R-22 and R-407C at non-uniform air and refrigerant distributions. EVAP5M was developed under this project to provide a tool for simulating a finned-tube air-to refrigerant evaporator operating with single-component refrigerants and refrigerant mixtures. The tube-by-tube modeling approach allowed for one-dimensional non-uniformity in the air velocity profile and arbitrary maldistribution on the refrigerant side. The model uses the Carnahan-Starling-DeSantis equation of state for calculating refrigerant thermodynamic properties. Simulations were performed for three evaporator slabs with different refrigerant circuitry designs. For the maldistributions studied, maldistributed air caused much more significant capacity degradation than maldistributed refrigerant. In some cases capacity decreased to as low as 57 percent of the value obtained for uniform velocity profile. Simulation results showed that R-22 and R-407C have similar susceptibility to capacity degradation. Relative change of capacity varied depending on the evaporator design and maldistribution studied. 17 refs., 18 figs., 9 tabs.

  4. In Situ-Grown ZnCo2O4 on Single-Walled Carbon Nanotubes as Air Electrode Materials for Rechargeable Lithium–Oxygen Batteries

    SciTech Connect

    Liu, Bin; Xu, Wu; Yan, Pengfei; Bhattacharya, Priyanka; Cao, Ruiguo; Bowden, Mark E.; Engelhard, Mark H.; Wang, Chong M.; Zhang, Jiguang

    2015-10-12

    Although lithium-oxygen (Li-O2) batteries have great potential to be used as one of the next generation energy storage systems due to their ultrahigh theoretical specific energy, there are still many significant barriers before their practical applications. These barriers include electrolyte and electrode instability, poor ORR/OER efficiency and cycling capability, etc. Development of a highly efficient catalyst will not only enhance ORR/OER efficiency, it may also improve the stability of electrolyte because the reduced charge voltage. Here we report the synthesis of nano-sheet-assembled ZnCo2O4 spheres/single walled carbon nanotubes (ZCO/SWCNTs) composites as high performance air electrode materials for Li-O2 batteries. The ZCO catalyzed SWCNTs electrodes delivered high discharge capacities, decreased the onset of oxygen evolution reaction by 0.9 V during charge processes, and led to more stable cycling stability. These results indicate that ZCO/SWCNTs composite can be used as highly efficient air electrode for oxygen reduction and evolution reactions. The highly enhanced catalytic activity by uniformly dispersed ZnCo2O4 catalyst on nanostructured electrodes is expected to inspire

  5. Membrane-electrode assemblies with high specific power based on functionalized carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Zabrodskii, A. G.; Glebova, N. V.; Nechitailov, A. A.; Terukova, E. E.; Terukov, E. I.; Tomasov, A. A.; Zelenina, N. K.

    2010-12-01

    It is demonstrated that the efficiency of catalysis and platinum usage in electrochemical energy converters can be improved by employing chemically functionalized multiwalled carbon tubes. On this basis, membrane-electrode assemblies for air-hydrogen fuel cells with specific powers up to 581 mW/cm2 have been obtained.

  6. Modeling air-driven flow of a viscous film coating the interior of a rigid, vertical tube

    NASA Astrophysics Data System (ADS)

    Ogrosky, Reed; Camassa, Roberto; Forest, Greg; Olander, Jeffrey

    2013-11-01

    The upwards, air-driven flow of a viscous fluid film coating the interior of a rigid, vertical tube is studied theoretically and numerically. The free surface of the film develops instabilities due to the interplay between interfacial stress from the airflow and surface tension from azimuthal curvature. Simple closure models for turbulent airflow coupled to long-wave asymptotic models for the liquid film have been shown to reproduce qualitatively the dynamics of the instabilities past initial transients observed in experiments. However, quantitative agreement requires improving the turbulent airflow modeling beyond leading order theories of free surface stress. An attempt in this direction is described here; the resulting model is compared with others in the literature and with experiments, for the case where the free surface is replaced by a rigid, wavy wall. This comparison is made for both wavy pipe and wavy channel flows, and the mean stress is seen to be out of phase with the wavy wall itself by a phase shift dependent on both the Reynolds number and the amplitude of the wall modulations. The free surface model is then studied through linear stability analysis and numerical solutions, both of which show improved agreement with experiments. We gratefully acknowledge support from NSF RTG DMS-0943851 and NIEHS 534197-3411.

  7. Frequency response of nonlinear oscillations of air column in a tube with an array of Helmholtz resonators.

    PubMed

    Sugimoto, N; Masuda, M; Hashiguchi, T

    2003-10-01

    Nonlinear cubic theory is developed to obtain a frequency response of shock-free, forced oscillations of an air column in a closed tube with an array of Helmholtz resonators connected axially. The column is assumed to be driven by a plane piston sinusoidally at a frequency close or equal to the lowest resonance frequency with its maximum displacement fixed. By applying the method of multiple scales, the equation for temporal modulation of a complex pressure amplitude of the lowest mode is derived in a case that a typical acoustic Mach number is comparable with the one-third power of the piston Mach number, while the relative detuning of a frequency is comparable with the quadratic order of the acoustic Mach number. The steady-state solution gives the asymmetric frequency response curve with bending (skew) due to nonlinear frequency upshift in addition to the linear downshift. Validity of the theory is checked against the frequency response obtained experimentally. For high amplitude of oscillations, an effect of jet loss at the throat of the resonator is taken into account, which introduces the quadratic loss to suppress the peak amplitude. It is revealed that as far as the present check is concerned, the weakly nonlinear theory can give quantitatively adequate description up to the pressure amplitude of about 3% to the equilibrium pressure.

  8. Mock-up tests on the combustion of hydrogen air mixture in the vertical tube simulating the CNS channel of the CARR

    NASA Astrophysics Data System (ADS)

    Yu, Qingfeng; Feng, Quanke; Kawai, Takeshi; Xu, Jian

    2007-01-01

    A two-phase thermo-siphon loop for removing nuclear heating and maintaining the stable liquid level in the moderator cell was adopted for the cold neutron source (CNS) of the China advanced research reactor (CARR). The moderator is liquid hydrogen. The two-phase thermo-siphon loop consists of the crescent-shape moderator cell, the moderator transfer tube, and the condenser. The hydrogen is supplied from the buffer tank to the condenser. The main feature of the loop is that the moderator cell is covered by the helium sub-cooling system. The cold helium gas from the helium refrigerator is firstly introduced into the helium sub-cooling system and then flows up through the tube covering the moderator transfer tube into the condenser. The main part of this system is installed in the CNS vertical channel made of aluminum alloy 6061 T6 (Al-6061-T6) of 6 mm in thickness, 270 mm in outer diameter and about 6 m in height. For confirming the safety of the CNS channel, the combustion tests using a tube compatible with the CNS channel were carried out using the hydrogen-air mixture under which air is introduced into the tube at 1 atmosphere, and then hydrogen gas is supplied from the gas cylinder up to the test pressures. And maximum test pressure is 0.14 MPa G. This condition is involved with the maximum design basis accident of the CARR-CNS. The peak pressure due to combustion was 1.09 MPa, and the design pressure of the CNS channel is 3 MPa. The safety of the CNS was thus verified even if the maximum design basis accident occurs. The pressure and stress distributions along the axial direction and the displacement of the tube were also measured.

  9. Shock shapes on blunt bodies in hypersonic-hypervelocity helium, air, and CO2 flows, and calibration results in Langley 6-inch expansion tube

    NASA Technical Reports Server (NTRS)

    Miller, C. G., III

    1975-01-01

    Shock shape results for flat-faced cylinders, spheres, and spherically blunted cones in various test gases, along with preliminary results from a calibration study performed in the Langley 6-inch expansion tube are presented. Free-stream velocities from 5 to 7 km/sec are generated at hypersonic conditions with helium, air, and CO2, resulting in normal shock density ratios from 4 to 19. Ideal-gas shock shape predictions, in which an effective ratio of specific heats is used as input, are compared with the measured results. The effect of model diameter is examined to provide insight to the thermochemical state of the flow in the shock layer. The regime for which equilibrium exists in the shock layer for the present air and CO2 test conditions is defined. Test core flow quality, test repeatability, and comparison of measured and predicted expansion-tube flow quantities are discussed.

  10. A Metal-Free, Free-Standing, Macroporous Graphene@g-C₃N₄ Composite Air Electrode for High-Energy Lithium Oxygen Batteries.

    PubMed

    Luo, Wen-Bin; Chou, Shu-Lei; Wang, Jia-Zhao; Zhai, Yu-Chun; Liu, Hua-Kun

    2015-06-01

    The nonaqueous lithium oxygen battery is a promising candidate as a next-generation energy storage system because of its potentially high energy density (up to 2-3 kW kg(-1)), exceeding that of any other existing energy storage system for storing sustainable and clean energy to reduce greenhouse gas emissions and the consumption of nonrenewable fossil fuels. To achieve high energy density, long cycling stability, and low cost, the air electrode structure and the electrocatalysts play important roles. Here, a metal-free, free-standing macroporous graphene@graphitic carbon nitride (g-C3N4) composite air cathode is first reported, in which the g-C3N4 nanosheets can act as efficient electrocatalysts, and the macroporous graphene nanosheets can provide space for Li2O2 to deposit and also promote the electron transfer. The electrochemical results on the graphene@g-C3N4 composite air electrode show a 0.48 V lower charging plateau and a 0.13 V higher discharging plateau than those of pure graphene air electrode, with a discharge capacity of nearly 17300 mA h g(-1)(composite) . Excellent cycling performance, with terminal voltage higher than 2.4 V after 105 cycles at 1000 mA h g(-1)(composite) capacity, can also be achieved. Therefore, this hybrid material is a promising candidate for use as a high energy, long-cycle-life, and low-cost cathode material for lithium oxygen batteries.

  11. Low resistance fuel electrodes

    DOEpatents

    Maskalick, Nichols J.; Folser, George R.

    1989-01-01

    An electrode 6 bonded to a solid, ion conducting electrolyte 5 is made, where the electrode 6 comprises a ceramic metal oxide 18, metal particles 17, and heat stable metal fibers 19, where the metal fibers provide a matrix structure for the electrode. The electrolyte 5 can be bonded to an air electrode cathode 4, to provide an electrochemical cell 2, preferably of tubular design.

  12. Quantification of VX vapor in ambient air by liquid chromatography isotope dilution tandem mass spectrometric analysis of glass bead filled sampling tubes.

    PubMed

    Evans, Ronald A; Smith, Wendy L; Nguyen, Nam-Phuong; Crouse, Kathy L; Crouse, Charles L; Norman, Steven D; Jakubowski, E Michael

    2011-02-15

    An analysis method has been developed for determining low parts-per-quadrillion by volume (ppqv) concentrations of nerve agent VX vapor actively sampled from ambient air. The method utilizes glass bead filled depot area air monitoring system (DAAMS) sampling tubes with isopropyl alcohol extraction and isotope dilution using liquid chromatography coupled with a triple-quadrupole mass spectrometer (LC/MS/MS) with positive ion electrospray ionization for quantitation. The dynamic range was from one-tenth of the worker population limit (WPL) to the short-term exposure limit (STEL) for a 24 L air sample taken over a 1 h period. The precision and accuracy of the method were evaluated using liquid-spiked tubes, and the collection characteristics of the DAAMS tubes were assessed by collecting trace level vapor generated in a 1000 L continuous flow chamber. The method described here has significant improvements over currently employed thermal desorption techniques that utilize a silver fluoride pad during sampling to convert VX to a higher volatility G-analogue for gas chromatographic analysis. The benefits of this method are the ability to directly analyze VX with improved selectivity and sensitivity, the injection of a fraction of the extract, quantitation using an isotopically labeled internal standard, and a short instrument cycle time.

  13. Ferrum nano particles and multiwall carbon nano tubes based electrode as FIA detector for determination of amino acids in hypothalamus microdialysis fluids

    NASA Astrophysics Data System (ADS)

    Sun, L.; Wang, J.; Wang, Y. T.; Yu, L.; Peng, H.; Zhu, J. Z.

    2017-01-01

    An amperometric electrode based on multiwall carbon nanotubes (MWCNTs) and Fe nanoparticles (NPs) has been successfully fabricated. Combined with Flow Injection Analysis (FIA) and chromatography separation column, the electrode exhibits linear response in the concentration range of 0.1 -12 μM and the sensitivity of 30.0 nA μM‑1 for most of amino acids. The determination of 17 amino acids in the hypothalamus microdialysis fluids of guinea pigs, illustrates that the electrode is a powerful tool to investigate physiology and pathology mechanisms

  14. The quantification of carbon dioxide in humid air and exhaled breath by selected ion flow tube mass spectrometry.

    PubMed

    Smith, David; Pysanenko, Andriy; Spanel, Patrik

    2009-05-01

    The reactions of carbon dioxide, CO(2), with the precursor ions used for selected ion flow tube mass spectrometry, SIFT-MS, analyses, viz. H(3)O(+), NO(+) and O(2) (+), are so slow that the presence of CO(2) in exhaled breath has, until recently, not had to be accounted for in SIFT-MS analyses of breath. This has, however, to be accounted for in the analysis of acetaldehyde in breath, because an overlap occurs of the monohydrate of protonated acetaldehyde and the weakly bound adduct ion, H(3)O(+)CO(2), formed by the slow association reaction of the precursor ion H(3)O(+) with CO(2) molecules. The understanding of the kinetics of formation and the loss rates of the relevant ions gained from experimentation using the new generation of more sensitive SIFT-MS instruments now allows accurate quantification of CO(2) in breath using the level of the H(3)O(+)CO(2) adduct ion. However, this is complicated by the rapid reaction of H(3)O(+)CO(2) with water vapour molecules, H(2)O, that are in abundance in exhaled breath. Thus, a study has been carried out of the formation of this adduct ion by the slow three-body association reaction of H(3)O(+) with CO(2) and its rapid loss in the two-body reaction with H(2)O molecules. It is seen that the signal level of the H(3)O(+)CO(2) adduct ion is sensitively dependent on the humidity (H(2)O concentration) of the sample to be analysed and a functional form of this dependence has been obtained. This has resulted in an appropriate extension of the SIFT-MS software and kinetics library that allows accurate measurement of CO(2) levels in air samples, ranging from very low percentage levels (0.03% typical of tropospheric air) to the 6% level that is about the upper limit in exhaled breath. Thus, the level of CO(2) can be traced through single time exhalation cycles along with that of water vapour, also close to the 6% level, and of trace gas metabolites that are present at only a few parts-per-billion. This has added a further dimension to

  15. Method for producing a tube

    DOEpatents

    Peterson, Kenneth A.; Rohde, Steven B.; Pfeifer, Kent B.; Turner, Timothy S.

    2007-01-02

    A method is described for producing tubular substrates having parallel spaced concentric rings of electrical conductors that can be used as the drift tube of an Ion Mobility Spectrometer (IMS). The invention comprises providing electrodes on the inside of a tube that are electrically connected to the outside of the tube through conductors that extend between adjacent plies of substrate that are combined to form the tube. Tubular substrates are formed from flexible polymeric printed wiring board materials, ceramic materials and material compositions of glass and ceramic, commonly known as Low Temperature Co-Fired Ceramic (LTCC). The adjacent plies are sealed together around the electrode.

  16. Manufacturing of Protected Lithium Electrodes for Advanced Lithium-Air, Lithium-Water & Lithium-Sulfur Batteries

    SciTech Connect

    Visco, Steven J

    2015-11-30

    The global demand for rechargeable batteries is large and growing rapidly. Assuming the adoption of electric vehicles continues to increase, the need for smaller, lighter, and less expensive batteries will become even more pressing. In this vein, PolyPlus Battery Company has developed ultra-light high performance batteries based on its proprietary protected lithium electrode (PLE) technology. The Company’s Lithium-Air and Lithium-Seawater batteries have already demonstrated world record performance (verified by third party testing), and we are developing advanced lithium-sulfur batteries which have the potential deliver high performance at low cost. In this program PolyPlus Battery Company teamed with Corning Incorporated to transition the PLE technology from bench top fabrication using manual tooling to a pre- commercial semi-automated pilot line. At the inception of this program PolyPlus worked with a Tier 1 battery manufacturing engineering firm to design and build the first-of-its-kind pilot line for PLE production. The pilot line was shipped and installed in Berkeley, California several months after the start of the program. PolyPlus spent the next two years working with and optimizing the pilot line and now produces all of its PLEs on this line. The optimization process successfully increased the yield, throughput, and quality of PLEs produced on the pilot line. The Corning team focused on fabrication and scale-up of the ceramic membranes that are key to the PLE technology. PolyPlus next demonstrated that it could take Corning membranes through the pilot line process to produce state-of-the-art protected lithium electrodes. In the latter part of the program the Corning team developed alternative membranes targeted for the large rechargeable battery market. PolyPlus is now in discussions with several potential customers for its advanced PLE-enabled batteries, and is building relationships and infrastructure for the transition into manufacturing. It is likely

  17. Tube support

    DOEpatents

    Mullinax, Jerry L.

    1988-01-01

    A tube support for supporting horizontal tubes from an inclined vertical support tube passing between the horizontal tubes. A support button is welded to the vertical support tube. Two clamping bars or plates, the lower edges of one bearing on the support button, are removably bolted to the inclined vertical tube. The clamping bars provide upper and lower surface support for the horizontal tubes.

  18. Substantial reduction of the heat losses to ambient air by natural convection from horizontal in-tube flows: impact of an axial bundle of passive baffles

    NASA Astrophysics Data System (ADS)

    Campo, A.; Cortés, C.

    This paper is concerned with a distinct and effective technique to insulate horizontal tubes carrying hot fluids without using the variety of insulating materials traditionally utilized in industry. The tubes transport hot fluids and are exposed to a natural convection environment of air at standard atmospheric temperature and pressure. Essentially, an ``equivalent quantity of insulation'' is provided by an envelope of straight symmetric baffles made from a low conductivity material that is affixed to the outer surface of the horizontal tubes. A simple 1-D lumped model of comparable precision to the customary 2-D differential model serves to regulate the thermal interaction between the two perpendicular fluid streams, one horizontal due to internal forced convection and the other vertical due to external natural convection in air. All computations are algebraic and lead to a rapid determination of the two quantities that are indispensable to design engineers: the mean bulk temperatures of the internal hot fluid moving either laminarly or turbulently, together with the degraded levels of heat transfer rates.

  19. Experiments of high-amplitude and shock-free oscillations of air column in a tube with array of Helmholtz resonators.

    PubMed

    Masuda, M; Sugimoto, N

    2005-07-01

    This experimental study is made to verify the weakly nonlinear theory for high-amplitude and shock-free oscillations of an air column developed in the previous paper [Sugimoto et al., J. Acoust. Soc. Am., 114, 1772-1784 (2003)]. The experiments use a new tube and resonators designed so as to not only avoid higher harmonic resonances and evanescences but also reduce the values of the coefficient of Q in the amplitude equation, and a rubber diaphragm sandwiched by circular plates to drive the air column. The steady-state pressure field in the tube and in the cavities of the resonators is measured, from which Fourier coefficients are obtained. In spite of nonlinearity, higher harmonics are suppressed significantly as designed, and the frequency response measured shows quantitatively good agreement with the one predicted up to about 170 dB (SPL). The first harmonics and the nonoscillatory component in the pressure field are well predicted, though the second harmonics show a quantitative discrepancy with the theory. In view of the good agreement of the frequency response, it is concluded that the theory is valid and useful enough to provide guidelines in designing the tube with the array of resonators.

  20. Heating rate measurements over 30 deg and 40 deg (half angle) blunt cones in air and helium in the Langley expansion tube facility

    NASA Technical Reports Server (NTRS)

    Reddy, N. M.

    1980-01-01

    Convective heat transfer measurements, made on the conical portion of spherically blunted cones (30 deg and 40 deg half angle) in an expansion tube are discussed. The test gases used were helium and air; flow velocities were about 6.8 km/sec for helium and about 5.1 km/sec for air. The measured heating rates are compared with calculated results using a viscous shock layer computer code. For air, various techniques to determine flow velocity yielded identical results, but for helium, the flow velocity varied by as much as eight percent depending on which technique was used. The measured heating rates are in satisfactory agreement with calculation for helium, assuming the lower flow velocity, the measurements are significantly greater than theory and the discrepancy increased with increasing distance along the cone.

  1. Ear Tubes

    MedlinePlus

    ... Marketplace Find an ENT Doctor Near You Ear Tubes Ear Tubes Patient Health Information News media interested ... throat specialist) may be considered. What are ear tubes? Ear tubes are tiny cylinders placed through the ...

  2. Mobile selected ion flow tube mass spectrometry (SIFT-MS) devices and their use for pollution exposure monitoring in breath and ambient air-pilot study.

    PubMed

    Storer, Malina; Salmond, Jennifer; Dirks, Kim N; Kingham, Simon; Epton, Michael

    2014-09-01

    Studies of health effects of air pollution exposure are limited by inability to accurately determine dose and exposure of air pollution in field trials. We explored the feasibility of using a mobile selected ion flow tube mass spectrometry (SIFT-MS) device, housed in a van, to determine ambient air and breath levels of benzene, xylene and toluene following exercise in areas of high motor vehicle traffic. The breath toluene, xylene and benzene concentration of healthy subjects were measured before and after exercising close to a busy road. The concentration of the volatile organic compounds (VOCs), in ambient air were also analysed in real time. Exercise close to traffic pollution is associated with a two-fold increase in breath VOCs (benzene, xylene and toluene) with levels returning to baseline within 20 min. This effect is not seen when exercising away from traffic pollution sources. Situating the testing device 50 m from the road reduced any confounding due to VOCs in the inspired air prior to the breath testing manoeuvre itself. Real-time field testing for air pollution exposure is possible using a mobile SIFT-MS device. This device is suitable for exploring exposure and dose relationships in a number of large scale field test scenarios.

  3. First clinical experience with the air purge control and electrical remote-controlled tubing clamp in mini bypass.

    PubMed

    Huybregts, Rien M A J M; Veerman, Derk P; Vonk, Alexander B A; Nesselaar, Alfred F; Paulus, Reggie C E; Thone-Passchier, Deirdre H; Smith, Annette L; de Vroege, Roel

    2006-09-01

    Most mini bypass systems do not contain a venous and cardiotomy reservoir in the cardiopulmonary bypass (CPB) circuit and lack the capability to remove venous air. In conjunction with the manufacturer the air purge control system, a system which automatically removes air that is captured in a venous bubble trap, has been developed. This system is combined with an electrical remote clamp, which automatically clamps the arterial line in case air leaves the bubble trap. Twenty consecutive patients undergoing surgery with CPB were included in this clinical validation. Venous air was removed by the air purge control during bypass. The electrical remote clamp was never activated by the system, confirming that the air purge control adequately removed venous air during these cases. The air purge control, in conjunction with the electrical remote clamp, is a valuable safety feature in mini bypass, enhancing patient safety and user friendliness while providing a level of safety equivalent to those of conventional bypass systems.

  4. Recirculating electric air filter

    DOEpatents

    Bergman, W.

    1985-01-09

    An electric air filter cartridge has a cylindrical inner high voltage electrode, a layer of filter material, and an outer ground electrode formed of a plurality of segments moveably connected together. The outer electrode can be easily opened to remove or insert filter material. Air flows through the two electrodes and the filter material and is exhausted from the center of the inner electrode.

  5. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  6. In vivo electrode implanting system

    NASA Technical Reports Server (NTRS)

    Collins, Jr., Earl R. (Inventor)

    1989-01-01

    A cylindrical intramuscular implantable electrode is provided with a strip of fabric secured around it. The fabric is woven from a polyester fiber having loops of the fiber protruding. The end of the main cylindrical body is provided with a blunt conductive nose, and the opposite end is provided with a smaller diameter rear section with an annular groove to receive tips of fingers extending from a release tube. The fingers are formed to spring outwardly and move the fingertips out of the annular groove in order to release the electrode from the release tube when a sheath over the electrode is drawn back sufficiently. The sheath compresses the fingers of the release tube and the fabric loops until it is drawn back. Muscle tissue grows into the loops to secure the electrode in place after the sheath is drawn back. The entire assembly of electrode, release tube and sheath can be inserted into the patient's muscle to the desired position through a hypodermic needle. The release tube may be used to manipulate the electrode in the patient's muscle to an optimum position before the electrode is released.

  7. Evolution of the air/SF6 turbulent mixing zone for different lengths of SF6: shock tube visualizations and 3D simulations

    NASA Astrophysics Data System (ADS)

    Haas, Jean-Francois; Griffond, Jerome; Souffland, Denis; Bouzgarrou, Ghazi; Bury, Yannick; Jamme, Stephane

    2015-11-01

    A turbulent mixing zone (TMZ) is created in a vertical shock tube (based in ISAE DAEP) when a Mach 1.2 shock wave in air accelerates impulsively to 70 m/s an air/SF6 interface. The gases are initially separated by a thin nitrocellulose membrane maintained flat and parallel to the shock by two wire grids. The upper grid (SF6 side) of square mesh spacing hu 1.8 or 12.1 mm is expected to seed perturbation for the Richtmyer-Meshkov instability (RMI) while the lower grid with hl 1 mm is needed to prevent the membrane from bulging prior to the shot. The experiments were carried out for different lengths L of SF6 between the initial interface and the shock tube's end plate: 10, 15, 20, 25 and 30 cm. The time resolved Schlieren image processing based on space and frequency filtering yields similar evolution for the TMZ thickness. Before reshock, the thickness grows initially fast then slows down and reaches different values (10 to 14 mm) according to L. Soon after reshock, the TMZ thickness growths rate is 21 mm/ms independently of L and hu. Numerical Schlieren images generated from 3D numerical simulations (performed at CEA DAM IDF) are analyzed as the experimental ones for L 15 and 25 cm and for hu 1.8 and 12.1 mm. The very weak experimental dependence on hu is not obtained by simulation as expected from dimensional reasoning. This discrepancy remains paradoxical.

  8. Heat Transfer from High-Temperature Surfaces to Fluids. III - Correlation of Heat-Transfer Data for Air Flowing in Silicon Carbide Tube with Rounded Entrance, Inside Diameter of 3/4 Inch, and Effective Length of 12 Inches. Part 3; Correlation of Heat-Transfer Data for Air Flowing in Silicon Carbide Tube with Rounded Entrance, Inside Diameter of 3/4 Inch, and Effective Length of 12 Inches

    NASA Technical Reports Server (NTRS)

    Sams, Eldon W.; Desmon, Leland G.

    1949-01-01

    A heat-transfer investigation was conducted with air flowing through an electrically heated silicon carbide tube with a rounded entrance, an inside diameter of 3/4 inch, and an effective heat-transfer length of 12 inches over a range of Reynolds numbers up to 300,000 and a range of average inside-tube-wall temperature up to 2500 R. The highest corresponding local outside-tube-wall temperature was 3010 R. Correlation of the heat-transfer data using the conventional Nueselt relation wherein physical properties of the fluid were evaluated at average bulk temperature resulted in a separation of data with tube-wall-temperature level. A satisfactory correlation of the heat-transfer data was obtained, however, by the use of modified correlation parameters wherein the mass velocity G (or product of average air density and velocity evaluated at bulk temperature P(sub b)V(sub b)) in the Reynolds number was replaced by the product of average air velocity evaluated at the bulk temperature and density evaluated at either the average inside-tube-wall temperature or the average film temperature; in addition, all the physical properties of air were correspondingly evaluated at either the average inside-tube-wall temperature or the average film temperature.

  9. Manual tube-to-tubesheet welding torch

    DOEpatents

    Kiefer, Joseph H.; Smith, Danny J.

    1982-01-01

    A welding torch made of a high temperature plastic which fits over a tube intermediate the ends thereof for welding the juncture between the tube and the back side of a tube plate and has a ballooned end in which an electrode, filler wire guide, fiber optic bundle, and blanketing gas duct are disposed.

  10. Electrical Characteristics, Electrode Sheath and Contamination Layer Behavior of a Meso-Scale Premixed Methane-Air Flame Under AC/DC Electric Fields

    NASA Astrophysics Data System (ADS)

    Chen, Qi; Yan, Limin; Zhang, Hao; Li, Guoxiu

    2016-05-01

    Electrical characteristics of a nozzle-attached meso-scale premixed methane-air flame under low-frequency AC (0-4300 V, 0-500 Hz) and DC (0-3300 V) electric fields were studied. I-V curves were measured under different experimental conditions to estimate the magnitude of the total current 100-102 μA, the electron density 1015-1016 m-3 and further the power dissipation ≤ 0.7 W in the reaction zone. At the same time, the meso-scale premixed flame conductivity 10-4-10-3 Ω-1·m-1 as a function of voltage and frequency was experimentally obtained and was believed to represent a useful order-of magnitude estimate. Moreover, the influence of the collision sheath relating to Debye length (31-98 μm) and the contamination layer of an active electrode on measurements was discussed, based on the combination of simulation and theoretical analysis. As a result, the electrode sheath dimension was evaluated to less than 0.5 mm, which indicated a complex effect of the collision sheath on the current measurements. The surface contamination effect of an active electrode was further analyzed using the SEM imaging method, which showed elements immigration during the contamination layer formation process. supported by National Natural Science Foundation of China (No. 51376021), and the Fundamental Research Fund for Major Universities (No. 2013JBM079)

  11. Integrated structure vacuum tube

    NASA Technical Reports Server (NTRS)

    Dimeff, J.; Kerwin, W. J. (Inventor)

    1976-01-01

    High efficiency, multi-dimensional thin film vacuum tubes suitable for use in high temperature, high radiation environments are described. The tubes are fabricated by placing thin film electrode members in selected arrays on facing interior wall surfaces of an alumina substrate envelope. Cathode members are formed using thin films of triple carbonate. The photoresist used in photolithography aids in activation of the cathodes by carbonizing and reacting with the reduced carbonates when heated in vacuum during forming. The finely powdered triple carbonate is mixed with the photoresist used to delineate the cathode locations in the conventional solid state photolithographic manner. Anode and grid members are formed using thin films of refractory metal. Electron flow in the tubes is between grid elements from cathode to anode as in a conventional three-dimensional tube.

  12. TUBE TESTER

    DOEpatents

    Gittings, H.T. Jr.; Kalbach, J.F.

    1958-01-14

    This patent relates to tube testing, and in particular describes a tube tester for automatic testing of a number of vacuum tubes while in service and as frequently as may be desired. In it broadest aspects the tube tester compares a particular tube with a standard tube tarough a difference amplifier. An unbalanced condition in the circuit of the latter produced by excessive deviation of the tube in its characteristics from standard actuates a switch mechanism stopping the testing cycle and indicating the defective tube.

  13. Bridging Oriented Copper Nanowire-Graphene Composites for Solution-Processable, Annealing-Free, and Air-Stable Flexible Electrodes.

    PubMed

    Zhang, Wang; Yin, Zhenxing; Chun, Alvin; Yoo, Jeeyoung; Kim, Youn Sang; Piao, Yuanzhe

    2016-01-27

    One-dimensional flexible metallic nanowires (NWs) are of considerable interest for next-generation wearable devices. The unavoidable challenge for a wearable electrode is the assurance of high conductivity, flexibility, and durability with economically feasible materials and simple manufacturing processes. Here, we use a straightforward solvothermal method to prepare a flexible conductive material that contains reduced graphene oxide (RGO) nanosheets bridging oriented copper NWs. The GO-assistance route can successfully meet the criteria listed above and help the composite films maintain high conductivity and durable flexibility without any extra treatment, such as annealing or acid processes. The composite film exhibits a high electrical performance (0.808 Ω·sq(-1)) without considerable change over 30 days under ambient conditions. Moreover, the Cu NW-RGO composites can be deposited on polyester cloth as a lightweight wearable electrode with high durability and simple processability and are very promising for a wide variety of electronic devices.

  14. Electrode electrolyte interlayers containing cerium oxide for electrochemical fuel cells

    DOEpatents

    Borglum, Brian P.; Bessette, Norman F.

    2000-01-01

    An electrochemical cell is made having a porous fuel electrode (16) and a porous air electrode (13), with solid oxide electrolyte (15) therebetween, where the air electrode surface opposing the electrolyte has a separate, attached, dense, continuous layer (14) of a material containing cerium oxide, and where electrolyte (16) contacts the continuous oxide layer (14), without contacting the air electrode (13).

  15. Heat transfer to two-phase air/water mixtures flowing in small tubes with inlet disequilibrium

    NASA Technical Reports Server (NTRS)

    Janssen, J. M.; Florschuetz, L. W.; Fiszdon, J. P.

    1986-01-01

    The cooling of gas turbine components was the subject of considerable research. The problem is difficult because the available coolant, compressor bleed air, is itself quite hot and has relatively poor thermophysical properties for a coolant. Injecting liquid water to evaporatively cool the air prior to its contact with the hot components was proposed and studied, particularly as a method of cooling for contingency power applications. Injection of a small quantity of cold liquid water into a relatively hot coolant air stream such that evaporation of the liquid is still in process when the coolant contacts the hot component was studied. No approach was found whereby heat transfer characteristics could be confidently predicted for such a case based solely on prior studies. It was not clear whether disequilibrium between phases at the inlet to the hot component section would improve cooling relative to that obtained where equilibrium was established prior to contact with the hot surface.

  16. Verification of computer-aided designs of traveling-wave tubes utilizing novel dynamic refocusers and graphite electrodes for the multistage depressed collector

    NASA Technical Reports Server (NTRS)

    Ramins, P.; Kosmahl, H. G.; Force, D. A.; Palmer, R. W.; Dayton, J. A., Jr.

    1985-01-01

    A computational procedure for the design of TWT-refocuser-MDC systems was used to design a short dynamic refocusing system and highly efficient four-stage depressed collector for a 200-W, 8- to 18-GHz, TWT. The computations were carried out with advanced, multidimensional computer programs which model the electron beam as a series of disks of charge and follow their trajectories from the RF input of the TWT, through the slow-wave structure and refocusing section, to their points of impact in the depressed collector. Secondary emission losses in the MDC were treated semi-quantitatively by injecting a representative beam of secondary electrons into the MDC analysis at the point of impact of each primary beam. A comparison of computed and measured TWT and MDC performance showed very good agreement. The electrodes of the MDC were fabricated from a particular form of isotropic graphite that was selected for its low secondary electron yield, ease of machinability, and vacuum properties. This MDC was tested (at CW) for more than 1000 hr with negligible degradation in TWT and MDC performances.

  17. Free compression tube. Applications

    NASA Astrophysics Data System (ADS)

    Rusu, Ioan

    2012-11-01

    During the flight of vehicles, their propulsion energy must overcome gravity, to ensure the displacement of air masses on vehicle trajectory, to cover both energy losses from the friction between a solid surface and the air and also the kinetic energy of reflected air masses due to the impact with the flying vehicle. The flight optimization by increasing speed and reducing fuel consumption has directed research in the aerodynamics field. The flying vehicles shapes obtained through studies in the wind tunnel provide the optimization of the impact with the air masses and the airflow along the vehicle. By energy balance studies for vehicles in flight, the author Ioan Rusu directed his research in reducing the energy lost at vehicle impact with air masses. In this respect as compared to classical solutions for building flight vehicles aerodynamic surfaces which reduce the impact and friction with air masses, Ioan Rusu has invented a device which he named free compression tube for rockets, registered with the State Office for Inventions and Trademarks of Romania, OSIM, deposit f 2011 0352. Mounted in front of flight vehicles it eliminates significantly the impact and friction of air masses with the vehicle solid. The air masses come into contact with the air inside the free compression tube and the air-solid friction is eliminated and replaced by air to air friction.

  18. Recirculating electric air filter

    DOEpatents

    Bergman, Werner

    1986-01-01

    An electric air filter cartridge has a cylindrical inner high voltage eleode, a layer of filter material, and an outer ground electrode formed of a plurality of segments moveably connected together. The outer electrode can be easily opened to remove or insert filter material. Air flows through the two electrodes and the filter material and is exhausted from the center of the inner electrode.

  19. Thin tubular self-supporting electrode for solid oxide electrolyte electrochemical cells

    DOEpatents

    Carlson, W.G.; Ruka, R.J.

    1992-04-28

    A self-supporting, gas-permeable air electrode tube is made having a sintered structure of calcium-doped LaMnO[sub 3], a density of from 60% to 85% of theoretical density, and a Coefficient of Thermal Expansion of from 10.2 [times] 10[sup [minus]6]/C to 10.8 [times] 10[sup [minus]6]/C, where one end is open and the other end is sealed with a plug. 2 figs.

  20. Thin tubular self-supporting electrode for solid oxide electrolyte electrochemical cells

    DOEpatents

    Carlson, William G.; Ruka, Roswell J.

    1992-01-01

    A self-supporting, gas-permeable air electrode tube (16) is made having a sintered structure of calcium-doped LaMnO.sub.3, a density of from 60% to 85% of theoretical density, and a Coefficient of Thermal Expansion of from 10.2.times.10.sup.-6 /.degree.C. to 10.8.times.10.sup.-6 /.degree.C., where one end is open and the other end is sealed with a plug (30).

  1. Effect of pH in a Pd-based ethanol membraneless air breathing nanofluidic fuel cell with flow-through electrodes

    NASA Astrophysics Data System (ADS)

    López-Rico, C. A.; Galindo-de-la-Rosa, J.; Ledesma-García, J.; Arriaga, L. G.; Guerra-Balcázar, M.; Arjona, N.

    2015-12-01

    In this work, a nanofluidic fuel cell (NFC) in which streams flow through electrodes was used to investigate the role of pH in the cell performance using ethanol as fuel and two Pd nanoparticles as electrocatalysts: one commercially available (Pd/C from ETEK) and other synthesized using ionic liquids (Pd/C IL). The cell performances for both electrocatalysts in acid/acid (anodic/cathodic) streams were of 18.05 and 9.55 mW cm-2 for Pd/C ETEK and Pd/C IL. In alkaline/alkaline streams, decrease to 15.94 mW cm-2 for Pd/C ETEK and increase to 15.37 mW cm-2 for Pd/C IL. In alkaline/acidic streams both electrocatalysts showed similar cell voltages (up to 1 V); meanwhile power densities were of 87.6 and 99.4 mW cm-2 for Pd/C ETEK and Pd/C IL. The raise in cell performance can be related to a decrease in activation losses, the combined used of alkaline and acidic streams and these high values compared with flow-over fuel cells can be related to the enhancement of the cathodic mass transport by using three dimensional porous electrodes and two sources of oxygen: from air and from a saturated solution.

  2. Variations in the structure and electrochemical characteristics of membrane electrode assemblies during the endurance testing of hydrogen-air fuel cells

    NASA Astrophysics Data System (ADS)

    Avakov, V. B.; Aliev, A. D.; Bogdanovskaya, V. A.; Ivanitskii, B. A.; Kazanskii, L. P.; Kapustin, A. V.; Korchagin, O. V.; Landgraf, I. K.; Tarasevich, M. P.; Chalykh, A. E.

    2015-05-01

    Variations in the characteristics of a membrane-electrode assembly (MEA) are studied during the endurance testing of a hydrogen-air fuel cell (FC) based on a Nafion 212 proton conducting membrane and platinum catalysts. It is shown that the voltage drop observed during MEA testing was mainly due to physicochemical transformations of the cathode catalyst, i.e., the oxidation of platinum and its subsequent recrystallization with nanoparticle coarsening. It is established that the rate of degradation increases along with temperature and loading, and with periodic FC depressurization. It is concluded that the enhancing effects of additional factors of degradation, e.g., platinum ion transport to the proton-conducting membrane and corrosion of the carbon carrier, were responsible for these processes.

  3. Coupled modeling of water transport and air-droplet interaction in the electrode of a proton exchange membrane fuel cell

    NASA Astrophysics Data System (ADS)

    Esposito, Angelo; Pianese, Cesare; Guezennec, Yann G.

    In this work, an accurate and computationally fast model for liquid water transport within a proton exchange membrane fuel cell (PEMFC) electrode is developed by lumping the space-dependence of the relevant variables. Capillarity is considered as the main transport mechanism within the gas diffusion layer (GDL). The novelty of the model lies in the coupled simulation of the water transport at the interface between gas diffusion layer and gas flow channel (GFC). This is achieved with a phenomenological description of the process that allows its simulation with relative simplicity. Moreover, a detailed two-dimensional visualization of such interface is achieved via geometric simulation of water droplets formation, growth, coalescence and detachment on the surface of the GDL. The model is useful for optimization analysis oriented to both PEMFC design and balance of plant. Furthermore, the accomplishment of reduced computational time and good accuracy makes the model suitable for control strategy implementation to ensure PEM fuel cells operation within optimal electrode water content.

  4. A solvent-free microbial-activated air cathode battery paper platform made with pencil-traced graphite electrodes.

    PubMed

    Lee, Seung Ho; Ban, Ju Yeon; Oh, Chung-Hun; Park, Hun-Kuk; Choi, Samjin

    2016-06-23

    We present the fabrication of an ultra-low cost, disposable, solvent-free air cathode all-paper microbial fuel cell (MFC) that does not utilize any chemical treatments. The anode and cathode were fabricated by depositing graphite particles by drawing them on paper with a pencil (four strokes). Hydrophobic parchment paper was used as a proton exchange membrane (PEM) to allow only H(+) to pass. Air cathode MFC technology, where O2 was used as an electron acceptor, was implemented on the paper platform. The bioelectric current was generated by an electrochemical process involving the redox couple of microbial-activated extracellular electron transferred electrons, PEM-passed H(+), and O2 in the cathode. A fully micro-integrated pencil-traced MFC showed a fast start-time, producing current within 10 s after injection of bacterial cells. A single miniaturized all-paper air cathode MFC generated a maximum potential of 300 mV and a maximum current of 11 μA during 100 min after a single injection of Shewanella oneidensis. The micro-fabricated solvent-free air cathode all-paper MFC generated a power of 2,270 nW (5.68 mW/m(2)). The proposed solvent-free air cathode paper-based MFC device could be used for environmentally-friendly energy storage as well as in single-use medical power supplies that use organic matter.

  5. A solvent-free microbial-activated air cathode battery paper platform made with pencil-traced graphite electrodes

    PubMed Central

    Lee, Seung Ho; Ban, Ju Yeon; Oh, Chung-Hun; Park, Hun-Kuk; Choi, Samjin

    2016-01-01

    We present the fabrication of an ultra-low cost, disposable, solvent-free air cathode all-paper microbial fuel cell (MFC) that does not utilize any chemical treatments. The anode and cathode were fabricated by depositing graphite particles by drawing them on paper with a pencil (four strokes). Hydrophobic parchment paper was used as a proton exchange membrane (PEM) to allow only H+ to pass. Air cathode MFC technology, where O2 was used as an electron acceptor, was implemented on the paper platform. The bioelectric current was generated by an electrochemical process involving the redox couple of microbial-activated extracellular electron transferred electrons, PEM-passed H+, and O2 in the cathode. A fully micro-integrated pencil-traced MFC showed a fast start-time, producing current within 10 s after injection of bacterial cells. A single miniaturized all-paper air cathode MFC generated a maximum potential of 300 mV and a maximum current of 11 μA during 100 min after a single injection of Shewanella oneidensis. The micro-fabricated solvent-free air cathode all-paper MFC generated a power of 2,270 nW (5.68 mW/m2). The proposed solvent-free air cathode paper-based MFC device could be used for environmentally-friendly energy storage as well as in single-use medical power supplies that use organic matter. PMID:27333815

  6. A solvent-free microbial-activated air cathode battery paper platform made with pencil-traced graphite electrodes

    NASA Astrophysics Data System (ADS)

    Lee, Seung Ho; Ban, Ju Yeon; Oh, Chung-Hun; Park, Hun-Kuk; Choi, Samjin

    2016-06-01

    We present the fabrication of an ultra-low cost, disposable, solvent-free air cathode all-paper microbial fuel cell (MFC) that does not utilize any chemical treatments. The anode and cathode were fabricated by depositing graphite particles by drawing them on paper with a pencil (four strokes). Hydrophobic parchment paper was used as a proton exchange membrane (PEM) to allow only H+ to pass. Air cathode MFC technology, where O2 was used as an electron acceptor, was implemented on the paper platform. The bioelectric current was generated by an electrochemical process involving the redox couple of microbial-activated extracellular electron transferred electrons, PEM-passed H+, and O2 in the cathode. A fully micro-integrated pencil-traced MFC showed a fast start-time, producing current within 10 s after injection of bacterial cells. A single miniaturized all-paper air cathode MFC generated a maximum potential of 300 mV and a maximum current of 11 μA during 100 min after a single injection of Shewanella oneidensis. The micro-fabricated solvent-free air cathode all-paper MFC generated a power of 2,270 nW (5.68 mW/m2). The proposed solvent-free air cathode paper-based MFC device could be used for environmentally-friendly energy storage as well as in single-use medical power supplies that use organic matter.

  7. Feeding Tubes

    MedlinePlus

    ... Feeding Tubes Health Information Sheet Q & A with Experts Patient Stories Social Security Disability Application Process For Kids ... Feeding Tubes Health Information Sheet Q & A with Experts Patient Stories Social Security Disability Application Process For Kids ...

  8. Electrodes For Alkali-Metal Thermoelectric Converters

    NASA Technical Reports Server (NTRS)

    Williams, Roger M.; Wheeler, Bob L.; Jeffries-Nakamura, Barbara; Lamb, James L.; Bankston, C. Perry; Cole, Terry

    1989-01-01

    Combination of thin, porous electrode and overlying collector grid reduces internal resistance of alkali-metal thermoelectric converter cell. Low resistance of new electrode and grid boosts power density nearly to 1 W/cm2 of electrode area at typical operating temperatures of 1,000 to 1,300 K. Conductive grid encircles electrode film on alumina tube. Bus wire runs along tube to collect electrical current from grid. Such converters used to transform solar, nuclear, and waste heat into electric power.

  9. Long life reference electrode

    DOEpatents

    Yonco, R.M.; Nagy, Z.

    1987-07-30

    An external, reference electrode is provided for long term use with a high temperature, high pressure system. The electrode is arranged in a vertical, electrically insulative tube with an upper portion serving as an electrolyte reservoir and a lower portion in electrolytic communication with the system to be monitored. The lower end portion includes a flow restriction such as a porous plug to limit the electrolyte release into the system. A piston equalized to the system pressure is fitted into the upper portion of the tube to impart a small incremental pressure to the electrolyte. The piston is selected of suitable size and weight to cause only a slight flow of electrolyte through the porous plug into the high pressure system. This prevents contamination of the electrolyte but is of such small flow rate that operating intervals of a month or more can be achieved. 2 figs.

  10. Long life reference electrode

    DOEpatents

    Yonco, R.M.; Nagy, Z.

    1989-04-04

    An external, reference electrode is provided for long term use with a high temperature, high pressure system. The electrode is arranged in a vertical, electrically insulative tube with an upper portion serving as an electrolyte reservoir and a lower portion in electrolytic communication with the system to be monitored. The lower end portion includes a flow restriction such as a porous plug to limit the electrolyte release into the system. A piston equalized to the system pressure is fitted into the upper portion of the tube to impart a small incremental pressure to the electrolyte. The piston is selected of suitable size and weight to cause only a slight flow of electrolyte through the porous plug into the high pressure system. This prevents contamination of the electrolyte but is of such small flow rate that operating intervals of a month or more can be achieved. 2 figs.

  11. Long life reference electrode

    DOEpatents

    Yonco, Robert M.; Nagy, Zoltan

    1989-01-01

    An external, reference electrode is provided for long term use with a high temperature, high pressure system. The electrode is arranged in a vertical, electrically insulative tube with an upper portion serving as an electrolyte reservior and a lower portion in electrolytic communication with the system to be monitored. The lower end portion includes a flow restriction such as a porous plug to limit the electrolyte release into the system. A piston equalized to the system pressure is fitted into the upper portion of the tube to impart a small incremental pressure to the electrolyte. The piston is selected of suitable size and weight to cause only a slight flow of electrolyte through the porous plug into the high pressure system. This prevents contamination of the electrolyte but is of such small flow rate that operating intervals of a month or more can be achieved.

  12. Membrane reference electrode

    DOEpatents

    Redey, L.; Bloom, I.D.

    1988-01-21

    A reference electrode utilizes a small thin, flat membrane of a highly conductive glass placed on a small diameter insulator tube having a reference material inside in contact with an internal voltage lead. When the sensor is placed in a non-aqueous ionic electrolytic solution, the concentration difference across the glass membrane generates a low voltage signal in precise relationship to the concentration of the species to be measured, with high spatial resolution. 2 figs.

  13. Membrane reference electrode

    DOEpatents

    Redey, Laszlo; Bloom, Ira D.

    1989-01-01

    A reference electrode utilizes a small thin, flat membrane of a highly conductive glass placed on a small diameter insulator tube having a reference material inside in contact with an internal voltage lead. When the sensor is placed in a non-aqueous ionic electrolytic solution, the concentration difference across the glass membrane generates a low voltage signal in precise relationship to the concentration of the species to be measured with high spatial resolution.

  14. A hierarchical three-dimensional NiCo2O4 nanowire array/carbon cloth as an air electrode for nonaqueous Li-air batteries.

    PubMed

    Liu, Wei-Ming; Gao, Ting-Ting; Yang, Yin; Sun, Qian; Fu, Zheng-Wen

    2013-10-14

    A 3D NiCo2O4 nanowire array/carbon cloth (NCONW/CC) was employed as the cathode for Li-air batteries with a non-aqueous electrolyte. After its discharge, novel porous ball-like Li2O2 was found to be deposited on the tip of NiCo2O4 nanowires. The special structure of Li2O2 and active sites of catalysts are also discussed.

  15. Calculation and measurement of a neutral air flow velocity impacting a high voltage capacitor with asymmetrical electrodes

    SciTech Connect

    Malík, M. Primas, J.; Kopecký, V.; Svoboda, M.

    2014-01-15

    This paper deals with the effects surrounding phenomenon of a mechanical force generated on a high voltage asymmetrical capacitor (the so called Biefeld-Brown effect). A method to measure this force is described and a formula to calculate its value is also given. Based on this the authors derive a formula characterising the neutral air flow velocity impacting an asymmetrical capacitor connected to high voltage. This air flow under normal circumstances lessens the generated force. In the following part this velocity is measured using Particle Image Velocimetry measuring technique and the results of the theoretically calculated velocity and the experimentally measured value are compared. The authors found a good agreement between the results of both approaches.

  16. Displaced electrode process for welding

    DOEpatents

    Heichel, L.J.

    1975-08-26

    A method is described for the butt-welding of a relatively heavy mass to a relatively small mass such as a thin-wall tube. In butt-welding heat is normally applied at the joint between the two pieces which are butt-welded together. The application of heat at the joint results in overheating the tube which causes thinning of the tube walls and porosity in the tube material. This is eliminated by displacing the welding electrode away from the seam toward the heavier mass so that heat is applied to the heavy mass and not at the butt seam. Examples of the parameters used in welding fuel rods are given. The cladding and end plugs were made of Zircalloy. The electrode used was of 2 percent thoriated tungsten. (auth)

  17. Tracheostomy tubes.

    PubMed

    Hess, Dean R; Altobelli, Neila P

    2014-06-01

    Tracheostomy tubes are used to administer positive-pressure ventilation, to provide a patent airway, and to provide access to the lower respiratory tract for airway clearance. They are available in a variety of sizes and styles from several manufacturers. The dimensions of tracheostomy tubes are given by their inner diameter, outer diameter, length, and curvature. Differences in dimensions between tubes with the same inner diameter from different manufacturers are not commonly appreciated but may have important clinical implications. Tracheostomy tubes can be cuffed or uncuffed and may be fenestrated. Some tracheostomy tubes are designed with an inner cannula. It is important for clinicians caring for patients with a tracheostomy tube to appreciate the nuances of various tracheostomy tube designs and to select a tube that appropriately fits the patient. The optimal frequency of changing a chronic tracheostomy tube is controversial. Specialized teams may be useful in managing patients with a tracheostomy. Speech can be facilitated with a speaking valve in patients with a tracheostomy tube who are breathing spontaneously. In mechanically ventilated patients with a tracheostomy, a talking tracheostomy tube, a deflated cuff technique with a speaking valve, or a deflated cuff technique without a speaking valve can be used to facilitate speech.

  18. Monodisperse CoFe2O4 nanoparticles supported on Vulcan XC-72: High performance electrode materials for lithium-air and lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Şener, Tansel; Kayhan, Emine; Sevim, Melike; Metin, Önder

    2015-08-01

    Addressed herein is the preparation and the electrode performance of monodisperse CoFe2O4 nanoparticles (NPs) supported on Vulcan XC-72 for the Lithium-air battery (LAB) and Lithium-ion battery (LIB). Monodisperse CoFe2O4 NPs were synthesized by the thermal decomposition of cobalt(II) acetylacetonate and iron(III) acetylacetonate in oleylamine and oleic acid in the presence of 1,2-tetradecanediol and benzyl ether. As-prepared CoFe2O4 NPs with a particle size of 11 nm were then supported on Vulcan XC-72 (Vulcan-CoFe2O4) at different theoretical loadings (20, 40 and 60 wt % CoFe2O4 NPs) by using the simple liquid phase self assembly method. CoFe2O4 NPs dispersed on Vulcan-CoFe2O4 composites were characterized by transmission electron microscopy (TEM), powder X-ray diffraction (PXRD) and atomic absorption spectroscopy (AAS). The AAS analyses indicated that the Vulcan-CoFe2O4 composites with different loadings were included 3.7, 8.1 and 16.4 wt % CoFe2O4 on the metal basis. The electrode performance of Vulcan-CoFe2O4 composites were evaluated as the anode active material for LIB and cathode active material for LABs by performing the galvanostatic charge-discharge tests. The highest discharge capacity for both LAB (7510 mAh g(Vulcan+CoFe2O4)-1; 13380 mAh gCoFe2O4-1 @ 0.1C) and LIB (863 mAh g(Vulcan+CoFe2O4)-1; 9330 mAh gCoFe2O4-1@ 0.1C) was investigated with 16.4 wt % CoFe2O4.

  19. Substantially oxygen-free contact tube

    NASA Technical Reports Server (NTRS)

    Pike, James F. (Inventor)

    1993-01-01

    A device for arc welding is provided in which a continuously-fed electrode wire is in electrical contact with a contact tube. The contact tube is improved by using a substantially oxygen-free conductive alloy in order to reduce the amount of electrical erosion.

  20. Substantially Oxygen-Free Contact Tube

    NASA Technical Reports Server (NTRS)

    Pike, James F. (Inventor)

    1991-01-01

    A device for arc welding is provided in which a continuously-fed electrode wire is in electrical contact with a contact tube. The contact tube is improved by using a substantially oxygen-free conductive alloy in order to reduce the amount of electrical erosion.

  1. A selected ion flow tube study of the reactions of NO + and O + 2 ions with some organic molecules: The potential for trace gas analysis of air

    NASA Astrophysics Data System (ADS)

    Španěl, Patrik; Smith, David

    1996-02-01

    A study has been carried out using our selected ion flow tube apparatus of the reactions of NO+ and O+2 ions in their vibronic ground states with ten organic species: the hydrocarbons, benzene, toluene, isoprene, cyclopropane, and n-pentane; the oxygen-containing organics, methanol, ethanol, acetaldehyde, acetone, and diethyl ether. The major objectives of this work are, on the one hand, to fully understand the processes involved in these reactions and, on the other hand, to explore the potential of NO+ and O+2 as chemical ionization agents for the analysis of trace gases in air and on human breath. Amongst the NO+ reactions, charge transfer, hydride-ion transfer, and termolecular association occur, and the measured rate coefficients, k, for the reactions vary from immeasurably small to the maximum value, collisional rate coefficient, kc. The O+2 reactions are all fast, in each case the k being equal to or an appreciable fraction of kc, and charge transfer producing the parent organic ion or dissociative charge transfer resulting in two or three fragments of the parent ion are the reaction processes that occur. We conclude from these studies, and from previous studies, that NO+ ions and O+2 ions can be used to great effect as chemical ionization agents for trace gas analysis, especially in combination with H3O+ ions which we now routinely use for this purpose.

  2. Indoor air pollution from coal combustion and the risk of neural tube defects in a rural population in Shanxi Province, China.

    PubMed

    Li, Zhiwen; Zhang, Le; Ye, Rongwei; Pei, Lijun; Liu, Jianmeng; Zheng, Xiaoying; Ren, Aiguo

    2011-08-15

    The authors evaluated indoor air pollution from coal combustion (IAPCC) as a potential risk factor for neural tube defects (NTDs) in a rural population in Shanxi Province, China. The studied rural population has both high IAPCC exposure and a high prevalence of NTDs. A population-based case-control study was used to identify 610 NTD cases and 837 normal controls between November 2002 and December 2007. Information was collected within 1 week following delivery or pregnancy termination due to prenatal NTD diagnosis. The authors derived an exposure index by integrating a series of IAPCC-related characteristics concerning dwelling and lifestyle. Compared with women with no IAPCC exposure, women with any exposure at all had a 60% increased risk of having a child with an NTD (adjusted odds ratio (OR) = 1.6, 95% confidence interval (CI): 1.1, 2.1). An increased NTD risk was linked to both residential heating (adjusted OR = 1.7, 95% CI: 1.1, 2.4) and cooking (adjusted OR = 1.5, 95% CI: 1.1, 2.1). The risk increased with increases in the exposure index, showing a dose-response trend (P < 0.001). This is the first known study to link IAPCC to NTDs. Additional studies are needed to confirm the link between IAPCC and NTDs.

  3. Silver decorated LaMnO3 nanorod/graphene composite electrocatalysts as reversible metal-air battery electrodes

    NASA Astrophysics Data System (ADS)

    Hu, Jie; Liu, Qiunan; Shi, Lina; Shi, Ziwei; Huang, Hao

    2017-04-01

    Perovskite LaMnO3 nanorod/reduced graphene oxides (LMO-NR/RGO) decorated with Ag nanoparticles are studied as a bifunctional catalyst for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in alkaline electrolyte. LMO-NR/RGO composites are synthesized by using cetyltrimethyl ammonium bromide (CTAB) as template via a simple hydrothermal reaction followed by heat treatment; overlaying of Ag nanoparticles is obtained through a traditional silver mirror reaction. Electron microscopy reveals that LMO-NR is embedded between the sheets of RGO, and the material is homogeneously overlaid with Ag nanoparticles. The unique composite morphology of Ag/LMO-NR/RGO not only enhances the electron transport property by increasing conductivity but also facilitates the diffusion of electrolytes and oxygen. As confirmed by electrochemical testing, Ag/LMO-NR/RGO exhibits very strong synergy with Ag nanoparticles, LMO-NR, and RGO, and the catalytic activities of Ag/LMO-NR/RGO during ORR and OER are significantly improved. With the novel catalyst, the homemade zinc-air battery can be reversibly charged and discharged and display a stable cycle performance, indicating the great potential of this composite as an efficient bifunctional electrocatalyst for metal-air batteries.

  4. Electrode compositions

    DOEpatents

    Block, J.; Fan, X.

    1998-10-27

    An electrode composition is described for use as an electrode in a non-aqueous battery system. The electrode composition contains an electrically active powder in a solid polymer and, as a dispersant, a C{sub 8}-C{sub 15} alkyl capped oligomer of a hexanoic acid that is electrochemically inert at 2.5--4.5 volts.

  5. Electrode compositions

    DOEpatents

    Block, Jacob; Fan, Xiyun

    1998-01-01

    An electrode composition for use as an electrode in a non-aqueous battery system. The electrode composition contains an electrically active powder in a solid polymer and, as a dispersant, a C.sub.8 -C.sub.15 alkyl capped oligomer of a hexanoic acid that is electrochemically inert at 2.5-4.5 volts.

  6. OH density optimization in atmospheric-pressure plasma jet by using multiple ring electrodes

    NASA Astrophysics Data System (ADS)

    Yue, Y.; Pei, X.; Lu, X.

    2016-01-01

    OH radical is one of the important reactive species generated by non-equilibrium atmospheric-pressure plasma jets, which is believed to play an important role in plasma medicine applications such as cancer therapy, wound healing and sterilization. In this study, a method to increase OH density is proposed. By using multiple pairs of ring electrodes, we generate 3-5 times more OH radicals than in the common device which uses only one high-voltage ring electrode. Discharge imaging shows that the plasma plume with only one ring electrode is longer and its emission intensity is higher than those with multiple pairs of ring electrodes. Further studies indicate that the distribution of OH radicals is significantly influenced by the gas flow rate. At higher gas flow rates, the OH peak concentration is detected further away from the nozzle, and the position of the peak OH concentration correlates with the product of the gas flow velocity and the pulse duration. As observed from the emission spectra, multiple electrodes only enhance the plasma inside the tube rather than the plasma plume in the surrounding air. These results suggest that the OH radicals are mainly generated inside the tube and then delivered to the outer plasma plume region by the gas flow.

  7. A perovskite oxide with high conductivities in both air and reducing atmosphere for use as electrode for solid oxide fuel cells

    NASA Astrophysics Data System (ADS)

    Lan, Rong; Cowin, Peter I.; Sengodan, Sivaprakash; Tao, Shanwen

    2016-08-01

    Electrode materials which exhibit high conductivities in both oxidising and reducing atmospheres are in high demand for solid oxide fuel cells (SOFCs) and solid oxide electrolytic cells (SOECs). In this paper, we investigated Cu-doped SrFe0.9Nb0.1O3‑δ finding that the primitive perovskite oxide SrFe0.8Cu0.1Nb0.1O3‑δ (SFCN) exhibits a conductivity of 63 Scm‑1and 60 Scm‑1 at 415 °C in air and 5%H2/Ar respectively. It is believed that the high conductivity in 5%H2/Ar is related to the exsolved Fe (or FeCu alloy) on exposure to a reducing atmosphere. To the best of our knowledge, the conductivity of SrFe0.8Cu0.1Nb0.1O3‑δ in a reducing atmosphere is the highest of all reported oxides which also exhibit a high conductivity in air. Fuel cell performance using SrFe0.8Cu0.1Nb0.1O3‑δ as the anode, (Y2O3)0.08(ZrO2)0.92 as the electrolyte and La0.8Sr0.2FeO3‑δ as the cathode achieved a power density of 423 mWcm‑2 at 700 °C indicating that SFCN is a promising anode for SOFCs.

  8. A perovskite oxide with high conductivities in both air and reducing atmosphere for use as electrode for solid oxide fuel cells

    PubMed Central

    Lan, Rong; Cowin, Peter I.; Sengodan, Sivaprakash; Tao, Shanwen

    2016-01-01

    Electrode materials which exhibit high conductivities in both oxidising and reducing atmospheres are in high demand for solid oxide fuel cells (SOFCs) and solid oxide electrolytic cells (SOECs). In this paper, we investigated Cu-doped SrFe0.9Nb0.1O3−δ finding that the primitive perovskite oxide SrFe0.8Cu0.1Nb0.1O3−δ (SFCN) exhibits a conductivity of 63 Scm−1and 60 Scm−1 at 415 °C in air and 5%H2/Ar respectively. It is believed that the high conductivity in 5%H2/Ar is related to the exsolved Fe (or FeCu alloy) on exposure to a reducing atmosphere. To the best of our knowledge, the conductivity of SrFe0.8Cu0.1Nb0.1O3−δ in a reducing atmosphere is the highest of all reported oxides which also exhibit a high conductivity in air. Fuel cell performance using SrFe0.8Cu0.1Nb0.1O3−δ as the anode, (Y2O3)0.08(ZrO2)0.92 as the electrolyte and La0.8Sr0.2FeO3−δ as the cathode achieved a power density of 423 mWcm−2 at 700 °C indicating that SFCN is a promising anode for SOFCs. PMID:27545200

  9. Measurement of conductivity and permittivity on samples sealed in nuclear magnetic resonance tubes

    SciTech Connect

    Huang, W.; Angell, C. A.; Yarger, J. L.; Richert, R.

    2013-07-15

    We present a broadband impedance spectroscopy instrument designed to measure conductivity and/or permittivity for samples that are sealed in glass tubes, such as the standard 5 mm tubes used for nuclear magnetic resonance experiments. The calibrations and corrections required to extract the dielectric properties of the sample itself are outlined. It is demonstrated that good estimates of the value of dc-conductivity can be obtained even without correcting for the effects of glass or air on the overall impedance. The approach is validated by comparing data obtained from samples sealed in nuclear magnetic resonance tubes with those from standard dielectric cells, using glycerol and butylmethylimidazolium-hexafluorophosphate as respective examples of a molecular and an ionic liquid. This instrument and approach may prove useful for other studies of permittivity and conductivity where contact to the metal electrodes or to the ambient atmosphere needs to be avoided.

  10. Binder-Free and Carbon-Free 3D Porous Air Electrode for Li-O2 Batteries with High Efficiency, High Capacity, and Long Life.

    PubMed

    Luo, Wen-Bin; Gao, Xuan-Wen; Shi, Dong-Qi; Chou, Shu-Lei; Wang, Jia-Zhao; Liu, Hua-Kun

    2016-06-01

    Pt-Gd alloy polycrystalline thin film is deposited on 3D nickel foam by pulsed laser deposition method serving as a whole binder/carbon-free air electrode, showing great catalytic activity enhancement as an efficient bifunctional catalyst for the oxygen reduction and evolution reactions in lithium oxygen batteries. The porous structure can facilitate rapid O2 and electrolyte diffusion, as well as forming a continuous conductive network throughout the whole energy conversion process. It shows a favorable cycle performance in the full discharge/charge model, owing to the high catalytic activity of the Pt-Gd alloy composite and 3D porous nickel foam structure. Specially, excellent cycling performance under capacity limited mode is also demonstrated, in which the terminal discharge voltage is higher than 2.5 V and the terminal charge voltage is lower than 3.7 V after 100 cycles at a current density of 0.1 mA cm(-2) . Therefore, this electrocatalyst is a promising bifunctional electrocatalyst for lithium oxygen batteries and this depositing high-efficient electrocatalyst on porous substrate with polycrystalline thin film by pulsed laser deposition is also a promising technique in the future lithium oxygen batteries research.

  11. Feeding tube insertion - gastrostomy

    MedlinePlus

    ... tube insertion; G-tube insertion; PEG tube insertion; Stomach tube insertion; Percutaneous endoscopic gastrostomy tube insertion ... and down the esophagus, which leads to the stomach. After the endoscopy tube is inserted, the skin ...

  12. Magnetohydrodynamic electrode

    DOEpatents

    Boquist, Carl W.; Marchant, David D.

    1978-01-01

    A ceramic-metal composite suitable for use in a high-temperature environment consists of a refractory ceramic matrix containing 10 to 50 volume percent of a continuous high-temperature metal reinforcement. In a specific application of the composite, as an electrode in a magnetohydrodynamic generator, the one surface of the electrode which contacts the MHD fluid may have a layer of varying thickness of nonreinforced refractory ceramic for electrode temperature control. The side walls of the electrode may be coated with a refractory ceramic insulator. Also described is an electrode-insulator system for a MHD channel.

  13. Volume-surface barrier discharge in dried air in three-electrode system fed by impulse high voltage with nanosecond rise time

    NASA Astrophysics Data System (ADS)

    Malashin, Maxim; Rebrov, Igor; Nebogatkin, Sergey; Sokolova, Marina; Nikitin, Alexey; Voevodin, Vadim; Krivov, Sergey

    2016-08-01

    Results of experimental investigation of a volume-surface barrier discharge in a three-electrode system under periodic impulse voltage applied to the surface discharge (SD) electrodes and a d.c. potential applied to an additional third electrode are presented. It is shown that there is a strong influence of polarity and amplitude of the d.c. potential on the direct current "extracted" out of the surface discharge plasma layer by electric field of the third electrode. The amount of charged positive species that constitute the "extracted" current prevails under positive impulse voltage for low values of the negative d.c. potential of the third electrode. The amount of negative species prevails with higher values of the positive d.c. positive of the third electrode. Contribution to the topical issue "6th Central European Symposium on Plasma Chemistry (CESPC-6)", edited by Nicolas Gherardi, Ester Marotta and Cristina Paradisi

  14. Multi-tube arrangement for combustor and method of making the multi-tube arrangement

    SciTech Connect

    Ziminsky, Willy Steve

    2012-07-31

    A fuel injector tube includes a one piece, unitary, polygonal tube having an inlet end and an outlet end. The fuel injector tube further includes a fuel passage extending from the inlet end to the outlet end along a longitudinal axis of the polygonal tube, a plurality of air passages extending from the inlet end to the outlet end and surrounding the fuel passage, and a plurality of fuel holes. Each fuel hole connects an air passage with the fuel passage. The inlet end of the polygonal tube is formed into a fuel tube. A fuel injector includes a plurality of fuel injector tubes and a plate. The plurality of fuel tubes are connected to the plate adjacent the inlet ends of the plurality of fuel injector tubes.

  15. Gastrostomy Tube (G-Tube)

    MedlinePlus

    ... warmth at the tube site; discharge that's yellow, green, or foul-smelling; fever) excessive bleeding or drainage from the tube site severe abdominal pain persistent vomiting or diarrhea trouble passing gas or having a bowel movement pink-red tissue (called granulation tissue) coming out ...

  16. Liquid electrode

    DOEpatents

    Ekechukwu, Amy A.

    1994-01-01

    A dropping electrolyte electrode for use in electrochemical analysis of non-polar sample solutions, such as benzene or cyclohexane. The liquid electrode, preferably an aqueous salt solution immiscible in the sample solution, is introduced into the solution in dropwise fashion from a capillary. The electrolyte is introduced at a known rate, thus, the droplets each have the same volume and surface area. The electrode is used in making standard electrochemical measurements in order to determine properties of non-polar sample solutions.

  17. GEIGER-MULLER TYPE COUNTER TUBE

    DOEpatents

    Fowler, I.L.; Watt, L.A.K.

    1959-12-15

    A single counter tube capable of responding to a wide range of intensities is described. The counter tube comprises a tubular cathode and an anode extending centrally of the cathode. The spacing between the outer surface of the anode and the inner surface of the cathode is varied along the length of the tube to provide different counting volumes in adjacent portions of the tube. A large counting volume in one portion adjacent to a low-energy absorption window gives adequate sensitivity for measuring lowintensity radiation, while a smaller volume with close electrode spacing is provided in the counter to make possible measurement of intense garnma radiation fields.

  18. Structural and microstructural characterization and properties of new phases in the Nd-Sr-Co-(Fe/Mn)-O system as air-electrodes in SOFCs.

    PubMed

    Boulahya, K; Muñoz Gil, D; Hassan, M; García Martin, S; Amador, U

    2017-01-24

    New oxides of the (NdSr)n+1MO3n+1 (M = Co and Mn or Fe) series are reported. Compounds of composition NdSrCo0.75Fe0.25O4.10, NdSrCo0.75Mn0.25O4.08 and Nd0.5Sr1.5Co0.75Mn0.25O3.86 are the n = 1 members of the Ruddlesden-Popper homologous series (K2NiF4 structural type) as determined by X-ray diffraction and different transmission electron microscopy techniques. Their crystal structure consists of connected (Co-Fe/Mn)O6 octahedra blocks separated by (Nd/Sr)O rock-salt like layers along the c-axis. Interstitial oxygen atoms or anion vacancies are induced depending on composition. Oxides with interstitial oxygen show good performances as intermediate temperature solid oxide fuel cell (IT-SOFC) cathode. The area-specific resistance values of electrodes made of these oxides at 973 K in air are 0.18 Ω cm(2) for NdSrCo0.75Fe0.25O4.10 and NdSrCo0.75Mn0.25O4.08 (comparable to the one of the state-of-the-art materials proposed as cathodes in IT-SOFC), and 1.38 Ω cm(2) for Nd0.5Sr1.5Co0.75Mn0.25O3.86.

  19. Protective tubes for sodium heated water tubes

    DOEpatents

    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.

  20. 21 CFR 874.3930 - Tympanostomy tube with semipermeable membrane.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Tympanostomy tube with semipermeable membrane. 874... Tympanostomy tube with semipermeable membrane. (a) Identification. A tympanostomy tube with a semipermeable... to permit a free exchange of air between the outer ear and middle ear. The tube portion of the...

  1. 21 CFR 874.3930 - Tympanostomy tube with semipermeable membrane.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Tympanostomy tube with semipermeable membrane. 874... Tympanostomy tube with semipermeable membrane. (a) Identification. A tympanostomy tube with a semipermeable... to permit a free exchange of air between the outer ear and middle ear. The tube portion of the...

  2. 21 CFR 874.3930 - Tympanostomy tube with semipermeable membrane.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tympanostomy tube with semipermeable membrane. 874... Tympanostomy tube with semipermeable membrane. (a) Identification. A tympanostomy tube with a semipermeable... to permit a free exchange of air between the outer ear and middle ear. The tube portion of the...

  3. 21 CFR 874.3930 - Tympanostomy tube with semipermeable membrane.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Tympanostomy tube with semipermeable membrane. 874... Tympanostomy tube with semipermeable membrane. (a) Identification. A tympanostomy tube with a semipermeable... to permit a free exchange of air between the outer ear and middle ear. The tube portion of the...

  4. 21 CFR 874.3930 - Tympanostomy tube with semipermeable membrane.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Tympanostomy tube with semipermeable membrane. 874... Tympanostomy tube with semipermeable membrane. (a) Identification. A tympanostomy tube with a semipermeable... to permit a free exchange of air between the outer ear and middle ear. The tube portion of the...

  5. Standard surface grinder for precision machining of thin-wall tubing

    NASA Technical Reports Server (NTRS)

    Jones, A.; Kotora, J., Jr.; Rein, J.; Smith, S. V.; Strack, D.; Stuckey, D.

    1967-01-01

    Standard surface grinder performs precision machining of thin-wall stainless steel tubing by electrical discharge grinding. A related adaptation, a traveling wire electrode fixture, is used for machining slots in thin-walled tubing.

  6. Self-shielding flex-circuit drift tube, drift tube assembly and method of making

    DOEpatents

    Jones, David Alexander

    2016-04-26

    The present disclosure is directed to an ion mobility drift tube fabricated using flex-circuit technology in which every other drift electrode is on a different layer of the flex-circuit and each drift electrode partially overlaps the adjacent electrodes on the other layer. This results in a self-shielding effect where the drift electrodes themselves shield the interior of the drift tube from unwanted electro-magnetic noise. In addition, this drift tube can be manufactured with an integral flex-heater for temperature control. This design will significantly improve the noise immunity, size, weight, and power requirements of hand-held ion mobility systems such as those used for explosive detection.

  7. Liquid electrode

    DOEpatents

    Ekechukwu, A.A.

    1994-07-05

    A dropping electrolyte electrode is described for use in electrochemical analysis of non-polar sample solutions, such as benzene or cyclohexane. The liquid electrode, preferably an aqueous salt solution immiscible in the sample solution, is introduced into the solution in dropwise fashion from a capillary. The electrolyte is introduced at a known rate, thus, the droplets each have the same volume and surface area. The electrode is used in making standard electrochemical measurements in order to determine properties of non-polar sample solutions. 2 figures.

  8. Tube Feedings.

    ERIC Educational Resources Information Center

    Plummer, Nancy

    This module on tube feedings is intended for use in inservice or continuing education programs for persons who work in long-term care. Instructor information, including teaching suggestions and a listing of recommended audiovisual materials and their sources appear first. The module goal and objectives are then provided. A brief discussion follows…

  9. Fluidized bed combustor and tube construction therefor

    DOEpatents

    De Feo, Angelo; Hosek, William

    1981-01-01

    A fluidized bed combustor comprises a reactor or a housing which has a windbox distributor plate adjacent the lower end thereof which contains a multiplicity of hole and air discharge nozzles for discharging air and coal into a fluidized bed which is maintained above the distributor plate and below a take-off connection or flue to a cyclone separator in which some of the products of combustion are treated to remove the dust which is returned into the fluidized bed. A windbox is spaced below the fluidized bed and it has a plurality of tubes passing therethrough with the passage of combustion air and fluidizing air which passes through an air space so that fluidizing air is discharged into the reaction chamber fluidized bed at the bottom thereof to maintain the bed in a fluidized condition. A fluid, such as air, is passed through the tubes which extend through the windbox and provide a preheating of the combustion air and into an annular space between telescoped inner and outer tubes which comprise heat exchanger tubes or cooling tubes which extend upwardly through the distributor plate into the fluidized bed. The heat exchanger tubes are advantageously arranged so that they may be exposed in groups within the reactor in a cluster which is arranged within holding rings.

  10. Tube construction for fluidized bed combustor

    DOEpatents

    De Feo, Angelo; Hosek, William

    1984-01-01

    A fluidized bed combustor comprises a reactor or a housing which has a windbox distributor plate adjacent the lower end thereof which contains a multiplicity of hole and air discharge nozzles for discharging air and coal into a fluidized bed which is maintained above the distributor plate and below a take-off connection or flue to a cyclone separator in which some of the products of combustion are treated to remove the dust which is returned into the fluidized bed. A windbox is spaced below the fluidized bed and it has a plurality of tubes passing therethrough with the passage of combustion air and fluidizing air which passes through an air space so that fluidizing air is discharged into the reaction chamber fluidized bed at the bottom thereof to maintain the bed in a fluidized condition. A fluid, such as air, is passed through the tubes which extend through the windbox and provide a preheating of the combustion air and into an annular space between telescoped inner and outer tubes which comprise heat exchanger tubes or cooling tubes which extend upwardly through the distributor plate into the fluidized bed. The heat exchanger tubes are advantageously arranged so that they may be exposed in groups within the reactor in a cluster which is arranged within holding rings.

  11. Shielded capacitive electrode

    DOEpatents

    Kireeff Covo, Michel

    2013-07-09

    A device is described, which is sensitive to electric fields, but is insensitive to stray electrons/ions and unlike a bare, exposed conductor, it measures capacitively coupled current while rejecting currents due to charged particle collected or emitted. A charged particle beam establishes an electric field inside the beam pipe. A grounded metallic box with an aperture is placed in a drift region near the beam tube radius. The produced electric field that crosses the aperture generates a fringe field that terminates in the back surface of the front of the box and induces an image charge. An electrode is placed inside the grounded box and near the aperture, where the fringe fields terminate, in order to couple with the beam. The electrode is negatively biased to suppress collection of electrons and is protected behind the front of the box, so the beam halo cannot directly hit the electrode and produce electrons. The measured signal shows the net potential (positive ion beam plus negative electrons) variation with time, as it shall be observed from the beam pipe wall.

  12. Neutron tubes

    DOEpatents

    Leung, Ka-Ngo; Lou, Tak Pui; Reijonen, Jani

    2008-03-11

    A neutron tube or generator is based on a RF driven plasma ion source having a quartz or other chamber surrounded by an external RF antenna. A deuterium or mixed deuterium/tritium (or even just a tritium) plasma is generated in the chamber and D or D/T (or T) ions are extracted from the plasma. A neutron generating target is positioned so that the ion beam is incident thereon and loads the target. Incident ions cause D-D or D-T (or T-T) reactions which generate neutrons. Various embodiments differ primarily in size of the chamber and position and shape of the neutron generating target. Some neutron generators are small enough for implantation in the body. The target may be at the end of a catheter-like drift tube. The target may have a tapered or conical surface to increase target surface area.

  13. Electron tube

    DOEpatents

    Suyama, Motohiro [Hamamatsu, JP; Fukasawa, Atsuhito [Hamamatsu, JP; Arisaka, Katsushi [Los Angeles, CA; Wang, Hanguo [North Hills, CA

    2011-12-20

    An electron tube of the present invention includes: a vacuum vessel including a face plate portion made of synthetic silica and having a surface on which a photoelectric surface is provided, a stem portion arranged facing the photoelectric surface and made of synthetic silica, and a side tube portion having one end connected to the face plate portion and the other end connected to the stem portion and made of synthetic silica; a projection portion arranged in the vacuum vessel, extending from the stem portion toward the photoelectric surface, and made of synthetic silica; and an electron detector arranged on the projection portion, for detecting electrons from the photoelectric surface, and made of silicon.

  14. Chest tube insertion

    MedlinePlus

    Chest drainage tube insertion; Insertion of tube into chest; Tube thoracostomy; Pericardial drain ... When your chest tube is inserted, you will lie on your side or sit partly upright, with one arm over your head. Sometimes, ...

  15. Microwave Tubes.

    DTIC Science & Technology

    1980-06-02

    better possibilities). It should be stated, also, that there exists for both TWT and the klystron, quite straight forward theoretical approaches which can...methods of large signal calculations for coupled cavity TWTs . Copies of this internal memo can be made available to any recipient of this report. M716S GP"I...electrodes and magnetic fields. The magnetic fields, in some cases (klystrons and TWTs ), serve merely to focus the beam, that is, confine the electron

  16. Magnetohydrodynamic electrode

    DOEpatents

    Marchant, David D.; Killpatrick, Don H.

    1978-01-01

    An electrode capable of withstanding high temperatures and suitable for use as a current collector in the channel of a magnetohydrodynamic (MHD) generator consists of a sintered powdered metal base portion, the upper surface of the base being coated with a first layer of nickel aluminide, an intermediate layer of a mixture of nickel aluminide - refractory ceramic on the first layer and a third or outer layer of a refractory ceramic material on the intermediate layer. The sintered powdered metal base resists spalling by the ceramic coatings and permits greater electrode compliance to thermal shock. The density of the powdered metal base can be varied to allow optimization of the thermal conductivity of the electrode and prevent excess heat loss from the channel.

  17. Cermet electrode

    DOEpatents

    Maskalick, Nicholas J.

    1988-08-30

    Disclosed is a cermet electrode consisting of metal particles of nickel, cobalt, iron, or alloys or mixtures thereof immobilized by zirconia stabilized in cubic form which contains discrete deposits of about 0.1 to about 5% by weight of praseodymium, dysprosium, terbium, or a mixture thereof. The solid oxide electrode can be made by covering a substrate with particles of nickel, cobalt, iron, or mixtures thereof, growing a stabilized zirconia solid oxide skeleton around the particles thereby immobilizing them, contacting the skeleton with a compound of praseodymium, dysprosium, terbium, or a mixture thereof, and heating the skeleton to a temperature of at least 500.degree. C. The electrode can also be made by preparing a slurry of nickel, cobalt, iron, or mixture and a compound of praseodymium, dysprosium, terbium, or a mixture thereof, depositing the slurry on a substrate, heating the slurry to dryness, and growing a stabilized zirconia skeleton around the metal particles.

  18. Nasogastric feeding tube

    MedlinePlus

    Feeding - nasogastric tube; NG tube; Bolus feeding; Continuous pump feeding; Gavage tube ... If your child has an NG tube, try to keep your child from touching or pulling on the tube. After your nurse teaches you how to flush the tube ...

  19. Kundt's Tube Experiment Using Smartphones

    ERIC Educational Resources Information Center

    Parolin, Sara Orsola; Pezzi, Giovanni

    2015-01-01

    This article deals with a modern version of Kundt's tube experiment. Using economic instruments and a couple of smartphones, it is possible to "see" nodes and antinodes of standing acoustic waves in a column of vibrating air and to measure the speed of sound.

  20. Photoelectrochemical electrodes

    NASA Technical Reports Server (NTRS)

    Williams, R. M.; Rembaum, A. (Inventor)

    1983-01-01

    The surface of a moderate band gap semiconductor such as p-type molybdenum sulfide is modified to contain an adherent film of charge mediating ionene polymer containing an electroactive unit such as bipyridimium. Electron transport between the electrode and the mediator film is favorable and photocorrosion and recombination processes are suppressed. Incorporation of particles of catalyst such as platinum within the film provides a reduction in overvoltage. The polymer film is readily deposited on the electrode surface and can be rendered stable by ionic or addition crosslinking. Catalyst can be predispersed in the polymer film or a salt can be impregnated into the film and reduced therein.

  1. Tube Thoracostomy (Chest Tube) Removal in Traumatic Patients: What Do We Know? What Can We Do?

    PubMed Central

    Paydar, Shahram; Ghahramani, Zahra; Ghoddusi Johari, Hamed; Khezri, Samad; Ziaeian, Bizhan; Ghayyoumi, Mohammad Ali; Fallahi, Mohammad Javad; Niakan, Mohammad Hadi; Sabetian, Golnar; Abbasi, Hamid Reza; Bolandparvaz, Shahram

    2015-01-01

    Chest tube (CT) or tube thoracostomy placement is often indicated following traumatic injuries. Premature movement of the chest tube leads to increased hospital complications and costs for patients. Placement of a chest tube is indicated in drainage of blood, bile, pus, drain air, and other fluids. Although there is a general agreement for the placement of a chest tube, there is little consensus on the subsequent management. Chest tube removal in trauma patients increases morbidity and hospital expense if not done at the right time. A review of relevant literature showed that the best answers to some questions about time and decision-making have been long sought. Issues discussed in this manuscript include chest tube removal conditions, the need for chest radiography before and after chest tuberemoval, the need to clamp the chest tube prior to removal, and drainage rate and acceptability prior to removal. PMID:27162900

  2. Investigation of capillary nanosecond discharges in air at moderate pressure: comparison of experiments and 2D numerical modelling

    NASA Astrophysics Data System (ADS)

    Klochko, Andrei V.; Starikovskaia, Svetlana M.; Xiong, Zhongmin; Kushner, Mark J.

    2014-09-01

    Nanosecond electrical discharges in the form of ionization waves are of interest for rapidly ionizing and exciting complex gas mixtures to initiate chemical reactions. Operating with a small discharge tube diameter can significantly increase the specific energy deposition and so enable optimization of the initiation process. Analysis of the uniformity of energy release in small diameter capillary tubes will aid in this optimization. In this paper, results for the experimentally derived characteristics of nanosecond capillary discharges in air at moderate pressure are presented and compared with results from a two-dimensional model. The quartz capillary tube, having inner and outer diameters of 1.5 and 3.4 mm, is about 80 mm long and filled with synthetic dry air at 27 mbar. The capillary tube with two electrodes at the ends is inserted into a break of the central wire of a long coaxial cable. A metal screen around the tube is connected to the cable ground shield. The discharge is driven by a 19 kV 35 ns voltage pulse applied to the powered electrode. The experimental measurements are conducted primarily by using a calibrated capacitive probe and back current shunts. The numerical modelling focuses on the fast ionization wave (FIW) and the plasma properties in the immediate afterglow after the conductive plasma channel has been established between the two electrodes. The FIW produces a highly focused region of electric field on the tube axis that sustains the ionization wave that eventually bridges the electrode gap. Results from the model predict FIW propagation speed and current rise time that agree with the experiment.

  3. AIR RADIOACTIVITY MONITOR

    DOEpatents

    Bradshaw, R.L.; Thomas, J.W.

    1961-04-11

    The monitor is designed to minimize undesirable background buildup. It consists of an elongated column containing peripheral electrodes in a central portion of the column, and conduits directing an axial flow of radioactively contaminated air through the center of the column and pure air through the annular portion of the column about the electrodes. (AEC)

  4. Microvoltammetric Electrodes.

    DTIC Science & Technology

    1985-09-25

    Microvoltammetric Electrodes, J. 0. Howell, R. M. Wightman, Anal. Chem., 56, 524-529 (1984). 2. Flow Rate Independent Amperometric Cell , W. L. Caudill...Electroanal. Chem., 182, 113-122 (1985). C. List of all publications 1. Flow Rate Independent Amperometric Cell , W. L. Caudill, J. 0. Howell, R. M

  5. Radio-frequency capacitive discharge with non-flow-type and droplet-jet electrolytic electrodes

    SciTech Connect

    Gaisin, A. F.; Abdullin, I. Sh.; Basyrov, R. Sh.; Khaziev, R. M.; Samitova, G. T.; Shakirova, E. F.

    2014-12-15

    Results are presented from experimental studies of the shape, structure, and spectral characteristics of an RF capacitive discharge operating between a droplet-jet electrolytic electrode and an electrolytic cell in air at pressures of P = 10{sup 3}–10{sup 5} Pa, as well as of a discharge burning between a copper rod and the surface of non-flow electrolyte at atmospheric pressure. It is found that, at voltages of U ≥ 3500 V, the multichannel discharge burning between the rod and the electrolyte (saturated solution of NaCl in technical water) surface transforms into a torch discharge. Specific features of the burning of a discharge with a droplet electrolytic electrode are investigated. Different forms of discharges burning on the surface of a copper tube and an electrolyte jet are revealed.

  6. Tube furnace

    DOEpatents

    Foster, Kenneth G.; Frohwein, Eugene J.; Taylor, Robert W.; Bowen, David W.

    1991-01-01

    A vermiculite insulated tube furnace is heated by a helically-wound resistance wire positioned within a helical groove on the surface of a ceramic cylinder, that in turn is surroundingly disposed about a doubly slotted stainless steel cylindrical liner. For uniform heating, the pitch of the helix is of shorter length over the two end portions of the ceramic cylinder. The furnace is of large volume, provides uniform temperature, offers an extremely precise programmed heating capability, features very rapid cool-down, and has a modest electrical power requirement.

  7. Tube furnace

    SciTech Connect

    Foster, K.G.; Frohwein, E.J.; Taylor, R.W.; Bowen, D.W.

    1990-12-31

    A vermiculite insulated tube furnace is heated by a helically-wound resistance wire positioned within a helical groove on the surface of a ceramic cylinder, that in turn is surroundingly disposed about a doubly slotted stainless steel cylindrical liner. For uniform heating, the pitch of the helix is of shorter length over the two end portions of the ceramic cylinder. The furnace is of large volume, provides uniform temperature, offers an extremely precise programmed heating capability, features very rapid cool-down, and has a modest electrical power requirement.

  8. Tube furnace

    SciTech Connect

    Foster, K.G.; Frohwein, E.J.; Taylor, R.W.; Bowen, D.W.

    1990-01-01

    A vermiculite insulated tube furnace is heated by a helically-wound resistance wire positioned within a helical groove on the surface of a ceramic cylinder, that in turn is surroundingly disposed about a doubly slotted stainless steel cylindrical liner. For uniform heating, the pitch of the helix is of shorter length over the two end portions of the ceramic cylinder. The furnace is of large volume, provides uniform temperature, offers an extremely precise programmed heating capability, features very rapid cool-down, and has a modest electrical power requirement.

  9. System and method having multi-tube fuel nozzle with differential flow

    DOEpatents

    Hughes, Michael John; Johnson, Thomas Edward; Berry, Jonathan Dwight; York, William David

    2017-01-03

    A system includes a multi-tube fuel nozzle with a fuel nozzle body and a plurality of tubes. The fuel nozzle body includes a nozzle wall surrounding a chamber. The plurality of tubes extend through the chamber, wherein each tube of the plurality of tubes includes an air intake portion, a fuel intake portion, and an air-fuel mixture outlet portion. The multi-tube fuel nozzle also includes a differential configuration of the air intake portions among the plurality of tubes.

  10. A correlation to predict the heat flux on the air-side of a vapor chamber with overturn-U flattened tubes

    NASA Astrophysics Data System (ADS)

    Srimuang, Wasan; Limkaisang, Viroj

    2016-08-01

    The heat transfer characteristics of a conventional vapor chamber (CVC) and a loop vapor chamber (LVC) are compared. The vapor chambers consisted of a stainless steel box with different covers. The results indicated that the heat flux and convective heat transfer coefficient of the air-side of LVC is higher than CVC. An empirical correlation was developed to predict the convective heat transfer coefficient of the air-side of the LVC.

  11. Gastrostomy Tube Placement Without Nasogastric Tube: A Retrospective Evaluation in 85 Patients

    SciTech Connect

    Heberlein, Wolf E. Goodwin, Whitney J.; Wood, Clint E.; Yousaf, Muhammad; Culp, William C.

    2012-12-15

    Purpose: Our study evaluated techniques for percutaneous gastrostomy (G)-tube placement without the use of a nasogastric (NG) tube. Instead, direct puncture of a physiologic air bubble or effervescent-enhanced gastric bubble distention was performed in patients with upper digestive tract obstruction (UDTO) or psychological objections to NG tubes. Materials and Methods: A total of 886 patients underwent G-tube placement in our department during a period of 7 years. We present our series of 85 (9.6%) consecutive patients who underwent percutaneous G-tube placement without use of an NG tube. Results: Of these 85 patients, fluoroscopic guided access was attempted by direct puncture of a physiologically present gastric air bubble in 24 (28%) cases. Puncture of an effervescent-induced large gastric air bubble was performed in 61 (72%) patients. Altogether, 82 (97%) of 85 G tubes were successfully placed in this fashion. The three failures comprised refusal of effervescent, vomiting of effervescent, and one initial tube misplacement when a deviation from our standard technique occurred. Conclusion: The described techniques compare favorably with published large series on G-tube placement with an NG tube in place. The techniques are especially suited for patients with UDTO due to head, neck, or esophageal malignancies, but they should be considered as an alternative in all patients. Direct puncture of effervescent-enhanced gastric bubble distention is a safe, patient-friendly and effective technique.

  12. Tapered pulse tube for pulse tube refrigerators

    DOEpatents

    Swift, Gregory W.; Olson, Jeffrey R.

    1999-01-01

    Thermal insulation of the pulse tube in a pulse-tube refrigerator is maintained by optimally varying the radius of the pulse tube to suppress convective heat loss from mass flux streaming in the pulse tube. A simple cone with an optimum taper angle will often provide sufficient improvement. Alternatively, the pulse tube radius r as a function of axial position x can be shaped with r(x) such that streaming is optimally suppressed at each x.

  13. The secondary alkaline zinc electrode

    NASA Astrophysics Data System (ADS)

    McLarnon, Frank R.; Cairns, Elton J.

    1991-02-01

    The worldwide studies conducted between 1975 and 1990 with the aim of improving cell lifetimes of secondary alkaline zinc electrodes are overviewed. Attention is given the design features and characteristics of various secondary alkaline zinc cells, including four types of zinc/nickel oxide cell designs (vented static-electrolyte, sealed static-electrolyte, vibrating-electrode, and flowing-electrolyte); two types of zinc/air cells (mechanically rechargeable consolidated-electrode and mechanically rechargeable particulate-electrode); zinc/silver oxide battery; zinc/manganese dioxide cell; and zinc/ferric cyanide battery. Particular consideration is given to recent research in the fields of cell thermodynamics, zinc electrodeposition, zinc electrodissolution, zinc corrosion, electrolyte properties, mathematical and phenomenological models, osmotic pumping, nonuniform current distribution, and cell cycle-life perforamnce.

  14. Radiotracer Evaluation of the Contribution of Degradation Products of Phenolic Resins to the Poisoning of Electrodes in the 190 C Hydrogen/Air Fuel Cell.

    DTIC Science & Technology

    1980-12-01

    R.F. Pascoe , H.R. Kunz, "Surface Area Loss of Platinum Supported on Carbon in Phosphoric Acid Electrolyte", J. Electrochem. Soc. 127, 1219 (1980). 4...1a. SUPPLEMENTARY NOTES IS. KEY WORDS (Contin he a reverse side It noceasm, mid Identify by block number) Fuel cells, phosphoric acid , bipolar...plates, phenolic resins, composite graphite, Carbon-14, radiotracer, electro-catalyst, electrode poisoning, platinum on carbon catalyst, acid -resistant

  15. Surface potential distribution and airflow performance of different air-exposed electrode plasma actuators at different alternating current/direct current voltages

    SciTech Connect

    Yang, Liang; Yan, Hui-Jie; Qi, Xiao-Hua; Hua, Yue; Ren, Chun-Sheng

    2015-04-15

    Asymmetric surface dielectric barrier discharge (SDBD) plasma actuators have been intensely studied for a number of years due to their potential applications for aerodynamic control. In this paper, four types of actuators with different configurations of exposed electrode are proposed. The SDBD actuators investigated are driven by dual-power supply, referred to as a fixed AC high voltage and an adjustable DC bias. The effects of the electrode structures on the dielectric surface potential distribution, the electric wind velocity, and the mean thrust production are studied, and the dominative factors of airflow acceleration behavior are revealed. The results have shown that the actions of the SDBD actuator are mainly dependent on the geometry of the exposed electrode. Besides, the surface potential distribution can effectively affect the airflow acceleration behavior. With the application of an appropriate additional DC bias, the surface potential will be modified. As a result, the performance of the electric wind produced by a single SDBD can be significantly improved. In addition, the work also illustrates that the actuators with more negative surface potential present better mechanical performance.

  16. Detail, north end of console and pneumatic tube message port, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail, north end of console and pneumatic tube message port, also showing mirror to reflect view of communications switchboard - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  17. Telephone equipment room, showing channel terminal bank with vacuum tubes. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Telephone equipment room, showing channel terminal bank with vacuum tubes. View to east - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  18. 42 CFR 84.152 - Breathing tube test; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing tube test; minimum requirements. 84.152... Respirators § 84.152 Breathing tube test; minimum requirements. (a)(1) Type A and Type B supplied-air respirators shall employ one or two flexible breathing tubes of the nonkinking type which extend from...

  19. 42 CFR 84.172 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing tubes; minimum requirements. 84.172... Air-Purifying Particulate Respirators § 84.172 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:...

  20. 42 CFR 84.172 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing tubes; minimum requirements. 84.172... Air-Purifying Particulate Respirators § 84.172 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:...

  1. 42 CFR 84.152 - Breathing tube test; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing tube test; minimum requirements. 84.152... Respirators § 84.152 Breathing tube test; minimum requirements. (a)(1) Type A and Type B supplied-air respirators shall employ one or two flexible breathing tubes of the nonkinking type which extend from...

  2. 42 CFR 84.172 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tubes; minimum requirements. 84.172... Air-Purifying Particulate Respirators § 84.172 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:...

  3. 42 CFR 84.152 - Breathing tube test; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tube test; minimum requirements. 84.152... Respirators § 84.152 Breathing tube test; minimum requirements. (a)(1) Type A and Type B supplied-air respirators shall employ one or two flexible breathing tubes of the nonkinking type which extend from...

  4. 42 CFR 84.172 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing tubes; minimum requirements. 84.172... Air-Purifying Particulate Respirators § 84.172 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:...

  5. 42 CFR 84.172 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing tubes; minimum requirements. 84.172... Air-Purifying Particulate Respirators § 84.172 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:...

  6. 42 CFR 84.152 - Breathing tube test; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing tube test; minimum requirements. 84.152... Respirators § 84.152 Breathing tube test; minimum requirements. (a)(1) Type A and Type B supplied-air respirators shall employ one or two flexible breathing tubes of the nonkinking type which extend from...

  7. 42 CFR 84.152 - Breathing tube test; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing tube test; minimum requirements. 84.152... Respirators § 84.152 Breathing tube test; minimum requirements. (a)(1) Type A and Type B supplied-air respirators shall employ one or two flexible breathing tubes of the nonkinking type which extend from...

  8. Oriented nanotube electrodes for lithium ion batteries and supercapacitors

    DOEpatents

    Frank, Arthur J.; Zhu, Kai; Wang, Qing

    2013-03-05

    An electrode having an oriented array of multiple nanotubes is disclosed. Individual nanotubes have a lengthwise inner pore defined by interior tube walls which extends at least partially through the length of the nanotube. The nanotubes of the array may be oriented according to any identifiable pattern. Also disclosed is a device featuring an electrode and methods of fabrication.

  9. Mounting method improves electrical and vibrational characteristics of screen electrodes

    NASA Technical Reports Server (NTRS)

    Nelson, R. E.

    1969-01-01

    Electrical characteristics of the mesh or screen electrodes used in electron tubes are improved by decreasing the shunt capacitance of the tube while retaining the close spacing needed for the required resolution. Vibrational characteristics are enhanced by raising the natural resonant frequency.

  10. Tube-in-tube thermophotovoltaic generator

    DOEpatents

    Ashcroft, J.; Campbell, B.; DePoy, D.

    1998-06-30

    A thermophotovoltaic device includes at least one thermal radiator tube, a cooling tube concentrically disposed within each thermal radiator tube and an array of thermophotovoltaic cells disposed on the exterior surface of the cooling tube. A shell having a first end and a second end surrounds the thermal radiator tube. Inner and outer tubesheets, each having an aperture corresponding to each cooling tube, are located at each end of the shell. The thermal radiator tube extends within the shell between the inner tubesheets. The cooling tube extends within the shell through the corresponding apertures of the two inner tubesheets to the corresponding apertures of the two outer tubesheets. A plurality of the thermal radiator tubes can be arranged in a staggered or an in-line configuration within the shell. 8 figs.

  11. Tube-in-tube thermophotovoltaic generator

    SciTech Connect

    Ashcroft, John; Campbell, Brian; DePoy, David

    1998-01-01

    A thermophotovoltaic device includes at least one thermal radiator tube, a cooling tube concentrically disposed within each thermal radiator tube and an array of thermophotovoltaic cells disposed on the exterior surface of the cooling tube. A shell having a first end and a second end surrounds the thermal radiator tube. Inner and outer tubesheets, each having an aperture corresponding to each cooling tube, are located at each end of the shell. The thermal radiator tube extends within the shell between the inner tubesheets. The cooling tube extends within the shell through the corresponding apertures of the two inner tubesheets to the corresponding apertures of the two outer tubesheets. A plurality of the thermal radiator tubes can be arranged in a staggered or an in-line configuration within the shell.

  12. Gastrostomy feeding tube - bolus

    MedlinePlus

    Feeding - gastrostomy tube - bolus; G-tube - bolus; Gastrostomy button - bolus; Bard Button - bolus; MIC-KEY - bolus ... Your child's gastrostomy tube (G-tube) is a special tube in your child's stomach that will help deliver food and medicines until your ...

  13. Air Purification Effect of Positively and Negatively Charged Ions Generated by Discharge Plasma at Atmospheric Pressure

    NASA Astrophysics Data System (ADS)

    Nishikawa, Kazuo; Nojima, Hideo

    2001-08-01

    In this paper, the air purification effect of positively and negatively charged ions generated by discharge plasma at atmospheric pressure is reported. We have developed a novel ion generation device which consists of a cylindrical glass tube and attached inner and outer mesh electrodes. With the application of AC voltage between the electrodes, positively charged ions and negatively charged ions have been generated at atmospheric pressure. The ion densities of 3.0× 104--7.0× 104 counts/cm3 have been obtained with the AC voltage of 1.8-2.3 kV (effective value). We have examined the air purification properties of this device. By the operation of this device, the initial oxygen nitride (NO) density of 10 ppm in 1 m3 (in cigarette smoke) was decreased to 1 ppm after 30 min. The number of suspended germs in air has been significantly reduced by the use of this type of ion generation device.

  14. FUEL CELL ELECTRODES FOR ACID MEDIA

    DTIC Science & Technology

    fuel cell electrodes for acid media. Activated carbon electrodes were prepared, wetproofed with paraffin or Teflon, and catalyzed with platinum. The wetproofing agent was applied by immersion or electrodeposition and the catalyst applied by chemical decomposition of H2P+Cl6 solutions. Half cell studies with hydrogen anodes and oxygen (air) cathodes showed that electrochemical performance is essentially the same for paraffin and Teflontreated electrodes; however, the life of the Teflon-treated electrodes under equal conditions of load is greater than that for

  15. Coulometric Study of Acetate Adsorption at a Polycrystalline Platinum Electrode

    DTIC Science & Technology

    2011-08-01

    wire was etched lightly in aqua regia , flame annealed, encased in shrinkable PTFE tubing to expose a 1-cm length, and then lightly etched again. The...was sealed in a shrinkable PTFE tube so as to conceal the weld. The electrode was etched in aqua regia and made cathodic at 24 mA for 17 min (past...of ~0.02 V versus a reversible hydrogen electrode. The electrode was rehydrogenated after several days of use and its potential was monitored against

  16. Electrochemical cell having cylindrical electrode elements

    DOEpatents

    Nelson, Paul A.; Shimotake, Hiroshi

    1982-01-01

    A secondary, high temperature electrochemical cell especially adapted for lithium alloy negative electrodes, transition metal chalcogenide positive electrodes and alkali metal halide or alkaline earth metal halide electrolyte is disclosed. The cell is held within an elongated cylindrical container in which one of the active materials is filled around the outside surfaces of a plurality of perforate tubular current collectors along the length of the container. Each of the current collector tubes contain a concentric tubular layer of electrically insulative ceramic as an interelectrode separator. The active material of opposite polarity in elongated pin shape is positioned longitudinally within the separator layer. A second electrically conductive tube with perforate walls can be swagged or otherwise bonded to the outer surface of the pin as a current collector and the electrically insulative ceramic layer can be coated or otherwise layered onto the outer surface of this second current collector. Alternatively, the central pin electrode can include an axial core as a current collector.

  17. Feeding tube - infants

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/007235.htm Feeding tube - infants To use the sharing features on this page, please enable JavaScript. A feeding tube is a small, soft, plastic tube placed ...

  18. Tracheostomy tube - eating

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000464.htm Tracheostomy tube - eating To use the sharing features on this ... you swallow foods or liquids. Eating and Tracheostomy Tubes When you get your tracheostomy tube, or trach, ...

  19. Eustachian tube patency

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/001630.htm Eustachian tube patency To use the sharing features on this page, please enable JavaScript. Eustachian tube patency refers to how much the eustachian tube ...

  20. Graphene-based battery electrodes having continuous flow paths

    DOEpatents

    Zhang, Jiguang; Xiao, Jie; Liu, Jun; Xu, Wu; Li, Xiaolin; Wang, Deyu

    2014-05-24

    Some batteries can exhibit greatly improved performance by utilizing electrodes having randomly arranged graphene nanosheets forming a network of channels defining continuous flow paths through the electrode. The network of channels can provide a diffusion pathway for the liquid electrolyte and/or for reactant gases. Metal-air batteries can benefit from such electrodes. In particular Li-air batteries show extremely high capacities, wherein the network of channels allow oxygen to diffuse through the electrode and mesopores in the electrode can store discharge products.

  1. Heat exchanger tube mounts

    DOEpatents

    Wolowodiuk, W.; Anelli, J.; Dawson, B.E.

    1974-01-01

    A heat exchanger in which tubes are secured to a tube sheet by internal bore welding is described. The tubes may be moved into place in preparation for welding with comparatively little trouble. A number of segmented tube support plates are provided which allow a considerable portion of each of the tubes to be moved laterally after the end thereof has been positioned in preparation for internal bore welding to the tube sheet. (auth)

  2. Computer simulation of processes in solid-state laser radiators and amplifiers with glow-tube pumping: Electric-discharge pumping sources. Thermophysical processes in envelope and electrodes of pulse pumps

    NASA Astrophysics Data System (ADS)

    Gradov, V. M.; Zhiltsov, V. I.; Sklizkov, G. V.; Terentyev, Y. I.; Fedotov, S. I.; Shcherbakov, A. A.

    1986-03-01

    Thermophysical processes in pulse pumps for solid state lasers are analyzed on the basis of the results of computer simulation according to a theoretical model which includes mechanical and thermal stresses in the pump components. The thick walled pump envelope is assumed to be in a plane state of stress and strain under axisymmetric load consisting of internal pressure and heat. The corresponding system of equations covers pressure and temperature transients as well as the steady state mechnical and thermal stresses. The mathematical model emphasizes cathodic processes at the cathode surface and in the boundary layer. The corresponding system of equations is solvable by the Runge-Kutta method. Separate consideration is given to mechanical wear of the pump envelope and electrodes for which a physico-chemical structure and processes were also constructed and programmed.

  3. Metal-Air Batteries

    SciTech Connect

    Zhang, Jiguang; Bruce, Peter G.; Zhang, Gregory

    2011-08-01

    Metal-air batteries have much higher specific energies than most currently available primary and rechargeable batteries. Recent advances in electrode materials and electrolytes, as well as new designs on metal-air batteries, have attracted intensive effort in recent years, especially in the development of lithium-air batteries. The general principle in metal-air batteries will be reviewed in this chapter. The materials, preparation methods, and performances of metal-air batteries will be discussed. Two main metal-air batteries, Zn-air and Li-air batteries will be discussed in detail. Other type of metal-air batteries will also be described.

  4. A multi-electrode biomimetic electrolocation sensor

    NASA Astrophysics Data System (ADS)

    Mayekar, K.; Damalla, D.; Gottwald, M.; Bousack, H.; von der Emde, G.

    2012-04-01

    We present the concept of an active multi-electrode catheter inspired by the electroreceptive system of the weakly electric fish, Gnathonemus petersii. The skin of this fish exhibits numerous electroreceptor organs which are capable of sensing a self induced electrical field. Our sensor is composed of a sending electrode and sixteen receiving electrodes. The electrical field produced by the sending electrode was measured by the receiving electrodes and objects were detected by the perturbation of the electrical field they induce. The intended application of such a sensor is in coronary diagnostics, in particular in distinguishing various types of plaques, which are major causes of heart attack. For calibration of the sensor system, finite element modeling (FEM) was performed. To validate the model, experimental measurements were carried out with two different systems. The physical system was glass tubing with metal and plastic wall insertions as targets. For the control of the experiment and for data acquisition, the software LabView designed for 17 electrodes was used. Different parameters of the electric images were analyzed for the prediction of the electrical properties and size of the inserted targets in the tube. Comparisons of the voltage modulations predicted from the FEM model and the experiments showed a good correspondence. It can be concluded that this novel biomimetic method can be further developed for detailed investigations of atherosclerotic lesions. Finally, we discuss various design strategies to optimize the output of the sensor using different simulated models to enhance target recognition.

  5. Tube vibration in a half-scale sector model of a helical tube steam generator

    NASA Astrophysics Data System (ADS)

    Chen, S. S.; Jendrzejczyk, J. A.; Wambsganss, M. W.

    1983-12-01

    This paper presents the experimental technique and results of tests on a half-scale sector model of a steam generator helical coil tube bank. A series of tests was performed: (1) bench tests of a single helical tube in air; (2) tests of the sector model in air; (3) tests of the sector model in stationary water to determine natural frequencies and damping; (4) tests in flow. The experimental results reveal the general characteristics of the sector model and provide the information for the design evaluation of a helical tube array to avoid detrimental fluidelastic instability.

  6. Auto-ignition of toluene-doped n-heptane and iso-octane/air mixtures: High-pressure shock-tube experiments and kinetics modeling

    SciTech Connect

    Hartmann, M.; Fikri, M.; Schulz, C.; Gushterova, I.; Schiessl, R.; Maas, U.

    2011-01-15

    Toluene is often used as a fluorescent tracer for fuel concentration measurements, but without considering whether it affects the auto-ignition properties of the base fuel. We investigate the auto-ignition of pure toluene and its influence on the auto-ignition of n-heptane and iso-octane/air mixtures under engine-relevant conditions at typical tracer concentrations. Ignition delay times {tau}{sub ign} were measured behind reflected shock waves in mixtures with air at {phi}=1.0 and 0.5 at p=40 bar, over a temperature range of T=700-1200 K and compared to numerical results using two different mechanisms. Based on the models, information is derived about the relative influence of toluene on {tau}{sub ign} on the base fuels as function of temperature. For typical toluene tracer concentrations {<=}10%, the ignition delay time {tau}{sub ign} changes by less than 10% in the relevant pressure and temperature range. (author)

  7. A glass-sealed field emission x-ray tube based on carbon nanotube emitter for medical imaging

    NASA Astrophysics Data System (ADS)

    Yeo, Seung Jun; Jeong, Jaeik; Ahn, Jeung Sun; Park, Hunkuk; Kwak, Junghwan; Noh, Eunkyong; Paik, Sanghyun; Kim, Seung Hoon; Ryu, Jehwang

    2016-04-01

    We report the design and fabrication of a carbon nanotube based a glass-sealed field emission x-ray tube without vacuum pump. The x-ray tube consists of four electrodes with anode, focuser, gate, and cathode electrode. The shape of cathode is rectangular for isotropic focal spot size at anode target. The obtained x-ray images show clearly micrometer scale.

  8. Effects of Fuel Distribution on Detonation Tube Performance

    NASA Technical Reports Server (NTRS)

    Perkins, H. Douglas; Sung, Chih-Jen

    2003-01-01

    A pulse detonation engine uses a series of high frequency intermittent detonation tubes to generate thrust. The process of filling the detonation tube with fuel and air for each cycle may yield non-uniform mixtures. Uniform mixing is commonly assumed when calculating detonation tube thrust performance. In this study, detonation cycles featuring idealized non-uniform Hz/air mixtures were analyzed using a two-dimensional Navier-Stokes computational fluid dynamics code with detailed chemistry. Mixture non-uniformities examined included axial equivalence ratio gradients, transverse equivalence ratio gradients, and partially fueled tubes. Three different average test section equivalence ratios were studied; one stoichiometric, one fuel lean, and one fuel rich. All mixtures were detonable throughout the detonation tube. Various mixtures representing the same average test section equivalence ratio were shown to have specific impulses within 1% of each other, indicating that good fuel/air mixing is not a prerequisite for optimal detonation tube performance under conditions investigated.

  9. Bender/Coiler for Tubing

    NASA Technical Reports Server (NTRS)

    Stoltzfus, J. M.

    1983-01-01

    Easy-to-use tool makes coils of tubing. Tubing to be bend clamped with stop post. Die positioned snugly against tubing. Operator turns handle to slide die along tubing, pushing tubing into spiral groove on mandrel.

  10. Metal vapor laser including hot electrodes and integral wick

    DOEpatents

    Ault, Earl R.; Alger, Terry W.

    1995-01-01

    A metal vapor laser, specifically one utilizing copper vapor, is disclosed herein. This laser utilizes a plasma tube assembly including a thermally insulated plasma tube containing a specific metal, e.g., copper, and a buffer gas therein. The laser also utilizes means including hot electrodes located at opposite ends of the plasma tube for electrically exciting the metal vapor and heating its interior to a sufficiently high temperature to cause the metal contained therein to vaporize and for subjecting the vapor to an electrical discharge excitation in order to lase. The laser also utilizes external wicking arrangements, that is, wicking arrangements located outside the plasma tube.

  11. Metal vapor laser including hot electrodes and integral wick

    DOEpatents

    Ault, E.R.; Alger, T.W.

    1995-03-07

    A metal vapor laser, specifically one utilizing copper vapor, is disclosed herein. This laser utilizes a plasma tube assembly including a thermally insulated plasma tube containing a specific metal, e.g., copper, and a buffer gas therein. The laser also utilizes means including hot electrodes located at opposite ends of the plasma tube for electrically exciting the metal vapor and heating its interior to a sufficiently high temperature to cause the metal contained therein to vaporize and for subjecting the vapor to an electrical discharge excitation in order to lase. The laser also utilizes external wicking arrangements, that is, wicking arrangements located outside the plasma tube. 5 figs.

  12. Non-aqueous electrolytes for lithium-air batteries

    DOEpatents

    Amine, Khalil; Chen, Zonghai; Zhang, Zhengcheng

    2016-06-07

    A lithium-air cell includes a negative electrode; an air positive electrode; and a non-aqueous electrolyte which includes an anion receptor that may be represented by one or more of the formulas. ##STR00001##

  13. resterilizable electrode for electrosurgery

    NASA Technical Reports Server (NTRS)

    Engstrom, E. R.; Houge, J. C.

    1979-01-01

    Required properties of flexibility, electrical conductivity, tensile strength, and tear resistance of electrosurgical electrodes is retained through utilization of flexible-polymer/conductive particle composites for electrodes.

  14. Low circumferential voltage gradient self supporting electrode for solid oxide fuel cells

    DOEpatents

    Reichner, Philip

    1989-01-01

    The porous, self-supporting, elongated electrode is made, having at least two chambers through its axial length, the chambers separated by an electronically conductive member. This electrode can be an air electrode of a fuel cell, having a superimposed solid electrolyte and fuel electrode.

  15. Residual Strain Distribution in Bent Composite Boiler Tubes

    SciTech Connect

    Hubbard, Camden R; Gorti, Sarma B; Tang, Fei; Keiser, James R

    2006-01-01

    Kraft recovery boilers are typically constructed of carbon steel boiler tubes clad with a corrosion resistant layer, and these composite tubes are bent and welded together to form air port panels which enable the combustion air to enter the boiler. In this paper, the through-thickness residual strain in the carbon steel layer of non-heat-treated and heat-treated composite bent tubes were measured by neutron diffraction techniques and modeled by finite element modeling. The results can be used to optimize material selection and manufacturing processes to prevent stress corrosion and corrosion fatigue cracking in the boiler tubes.

  16. Electrically recharged battery employing a packed/spouted bed metal particle electrode

    DOEpatents

    Siu, Stanley C.; Evans, James W.; Salas-Morales, Juan

    1995-01-01

    A secondary metal air cell, employing a spouted/packed metal particle bed and an air electrode. More specifically a zinc air cell well suited for use in electric vehicles which is capable of being either electrically or hydraulically recharged.

  17. The Multiple Silicone Tube Device, “Tubes within a Tube,” for Multiplication in Nerve Reconstruction

    PubMed Central

    Dahlin, Lars B.

    2014-01-01

    Multiple nerve branches were created during the regeneration procedure after a nerve injury and such multiple branches are suggested to be used to control, for example, prosthesis with many degrees of freedom. Transected rat sciatic nerve stumps were inserted into a nine mm long silicone tube, which contained four, five mm long, smaller tubes, thus leaving a five mm gap for regenerating nerve fibers. Six weeks later, several new nerve structures were formed not only in the four smaller tubes, but also in the spaces in-between. The 7–9 new continuous nerve structures, which were isolated as individual free nerves after removal of the tubes, were delineated by a perineurium and contained both myelinated and unmyelinated nerve fibers as well as blood vessels. Stimulation of the proximal nerve elicited contractions in distal muscles. Thin metal electrodes, inserted initially into the smaller tubes in some experiments, became embedded in the new nerve structures and when stimulated contractions of the distal muscles were observed. The “tubes within a tube” technique, creating multiple new nerves from a single “mother” nerve, can be used to record multiple signals for prosthetic device control or as sources for supply of multiple denervated targets. PMID:24864255

  18. Electrode porosity and effective electrocatalyst activity in electrode-membrane-assemblies (MEAs) of PEMFCs

    SciTech Connect

    Fischer, A.; Wendt, H.

    1996-12-31

    New production technologies of membrane-electrode-assemblies for PEWCs which ensure almost complete catalyst utilization by {open_quotes}wetting{close_quotes} the internal catalyst surface with the ionomeric electrolyte, allow for a reduction of Pt-loadings from prior 4 mg cm{sup -2} to now less than 0.5 mg cm{sup -2}. Such electrodes are not thicker than from 5 to 10 {mu}m. Little has been published hitherto about the detailed micromorphology of such electrodes and the role of electrode porosity on electrode performance. It is well known, that the porosity of thicker fuel cell electrodes, e.g. of PAFC or AFC electrodes is decisive for their performance. Therefore the issue of this investigation is to measure and to modify the porosity of electrodes prepared by typical MEA production procedures and to investigate the influence of this porosity on the effective catalyst activity for cathodic reduction of oxygen from air in membrane cells. It may be anticipated that any mass transfer hindrance of gaseous reactants into porous electrodes would manifest itself rather in the conversion of dilute gases than in the conversion of pure gases (e.g. neat oxygen). Therefore in this investigation the performance of membrane cell cathodes with non pressurized air had been compared to that with neat oxygen at cathodes which had a relatively low Pt-loading of 0.15 mg cm{sup -2}.

  19. Ion-Selective Electrodes.

    ERIC Educational Resources Information Center

    Arnold, Mark A.; Meyerhoff, Mark E.

    1984-01-01

    Literature on ion-selective electrodes (ISEs) is reviewed in seven sections: books, conferences, reviews; potentiometric membrane electrodes; glass and solid-state membrane electrodes; liquid and polymer membrane ISEs; coated wire electrodes, ion-selective field effect transistors, and microelectrodes; gas sensors and selective bioelectrode…

  20. Method of pressure pulse cleaning a tube bundle heat exchanger

    SciTech Connect

    Scharton, T.D.; Taylor, G.B.

    1987-04-07

    A method is described of removing the products of corrosion, oxidation, sedimentation and comparable chemical reactions collectively known as sludge which settle on the bottom of a tube bundle heat exchange and form a pile of sludge. The tube bundle heat exchanger is characterized by a tube bundle heat exchanger wall and a thick metal plate known as a tube sheet near the lower portion of the tube bundle heat exchanger wall's interior surface. The tube sheet serves to support the lower ends of a multiplicity of heat exchanger tubes within the tube bundle heat exchanger. The tube bundle heat exchange wall further comprises a multiplicity of small holes known as hand holes, manways, drain lines and vents, located around its circumference and above the tube sheet. The method is described of removing the pile of sludge which settles on the tube sheet comprising: a. locating at least one air-gun type pressure pulse shock wave source outside the tube bundle heat exchanger so as to be able to introduce pressure pulse shock waves through one or more of the multiplicity of hand holes, manways, drain lines and vents; and b. filling the tube bundle heat exchanger with a liquid to a level above the pile of sludge.

  1. PEG tube insertion -- discharge

    MedlinePlus

    ... shower or bathe. Keeping the PEG-tube in Place If the feeding tube comes out, the stoma ... eds. Pfenninger and Fowler's Procedures for Primary Care . 3rd ed. Philadelphia, PA: Elsevier Mosby; 2011:chap 100. ...

  2. Glass tube splitting tool

    NASA Technical Reports Server (NTRS)

    Klein, J. A.; Murray, C. D.; Stein, J. A.

    1971-01-01

    Tool accurately splits glass tubing so cuts are aligned 180 deg apart and reassembled tube forms low pressure, gastight enclosure. Device should interest industries using cylindrical closed glass containers.

  3. Eustachian tube (image)

    MedlinePlus

    ... are more common in children because their eustachian tubes are shorter, narrower, and more horizontal than in ... become trapped when the tissue of the eustachian tube becomes swollen from colds or allergies. Bacteria trapped ...

  4. Neural Tube Defects

    MedlinePlus

    Neural tube defects are birth defects of the brain, spine, or spinal cord. They happen in the first month ... she is pregnant. The two most common neural tube defects are spina bifida and anencephaly. In spina ...

  5. HSPES membrane electrode assembly

    NASA Technical Reports Server (NTRS)

    Kindler, Andrew (Inventor); Yen, Shiao-Ping (Inventor)

    2000-01-01

    An improved fuel cell electrode, as well as fuel cells and membrane electrode assemblies that include such an electrode, in which the electrode includes a backing layer having a sintered layer thereon, and a non-sintered free-catalyst layer. The invention also features a method of forming the electrode by sintering a backing material with a catalyst material and then applying a free-catalyst layer.

  6. Guide tube flow diffuser

    SciTech Connect

    Berringer, R.T.; Myron, D.L.

    1980-11-04

    A nuclear reactor upper internal guide tube has a flow diffuser integral with its bottom end. The guide tube provides guidance for control rods during their ascent or descent from the reactor core. The flow diffuser serves to divert the upward flow of reactor coolant around the outside of the guide tube thereby limiting the amount of coolant flow and turbulence within the guide tube, thus enhancing the ease of movement of the control rods.

  7. Microhole Tubing Bending Report

    DOE Data Explorer

    Oglesby, Ken

    2012-01-01

    A downhole tubing bending study was made and is reported herein. IT contains a report and 2 excel spreadsheets to calculate tubing bending and to estimate contact points of the tubing to the drilled hole wall (creating a new support point).

  8. 1992 tubing tables

    SciTech Connect

    Not Available

    1992-01-01

    This paper is helpful to those designing oil well completions or purchasing tubing with proprietary or premium connections. Tables contain specifications and application data for over 100 different tubing joints, including those used with fiberglass pipe. The tables this year contain dimensional and performance data for coiled tubing.

  9. 66. Building 102, view of Klystron tubes located in test ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    66. Building 102, view of Klystron tubes located in test systems located at first floor level with top of tubes protruding through second floor and ready to be lit and installed through top of Klystron tube vaults to ready position. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  10. New electrosurgical ball electrode with nonstick properties

    NASA Astrophysics Data System (ADS)

    Rondinone, Joseph; Brassell, James; Miller, Scott A., III; Thorne, Jonathan O.; Rondinone, David M.; Safabash, Jason; Vega, Felix

    1998-04-01

    A new electrosurgical ball electrode (SilverBulletTM) has been developed for applying radiofrequency (RF) energy to fuse biological and other materials to tissue surfaces. Specifically, the electrode was developed for use in conjunction with the Fusion Medical Technologies, Inc. gelatin patch (RapiSealTM) for use in pulmonary surgery to seal air leaks, and in solid abdominal organ surgeries to provide hemostatic tamponade. The new electrode allows for the application of RF energy in contact mode without the problems of the electrode sticking to the gelatin patch or the underlying tissue. Designed for use with commercially available electrosurgical handpieces, the electrode consists of a stainless steel connector that fits into the hand- piece, and an electrode assembly made from silver that includes a shank region, and a tip extension extending distally from the shank region. The distal tip of the tip extension is rounded and has a length of about 10 mm. The uniqueness of this electrode is the shank region which has a cross sectional area that is larger than the tip extension. The shank region acts as a heat sink to draw away heat from the tip extension while the tip extension itself remains sufficiently small to access desired target sites and display the desired energy transfer properties. In addition to the physical design, the use of silver as the core element provides a material with high electrical and thermal conductivities. The bulk of the electrode is appropriately insulated.

  11. 21 CFR 868.5800 - Tracheostomy tube and tube cuff.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Tracheostomy tube and tube cuff. 868.5800 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5800 Tracheostomy tube and tube cuff. (a) Identification. A tracheostomy tube and tube cuff is a device intended to be placed into...

  12. 21 CFR 868.5800 - Tracheostomy tube and tube cuff.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Tracheostomy tube and tube cuff. 868.5800 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5800 Tracheostomy tube and tube cuff. (a) Identification. A tracheostomy tube and tube cuff is a device intended to be placed into...

  13. 21 CFR 868.5800 - Tracheostomy tube and tube cuff.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Tracheostomy tube and tube cuff. 868.5800 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5800 Tracheostomy tube and tube cuff. (a) Identification. A tracheostomy tube and tube cuff is a device intended to be placed into...

  14. Controlled porosity in electrodes

    DOEpatents

    Chiang, Yet-Ming; Bae, Chang-Jun; Halloran, John William; Fu, Qiang; Tomsia, Antoni P.; Erdonmez, Can K.

    2015-06-23

    Porous electrodes in which the porosity has a low tortuosity are generally provided. In some embodiments, the porous electrodes can be designed to be filled with electrolyte and used in batteries, and can include low tortuosity in the primary direction of ion transport during charge and discharge of the battery. In some embodiments, the electrodes can have a high volume fraction of electrode active material (i.e., low porosity). The attributes outlined above can allow the electrodes to be fabricated with a higher energy density, higher capacity per unit area of electrode (mAh/cm.sup.2), and greater thickness than comparable electrodes while still providing high utilization of the active material in the battery during use. Accordingly, the electrodes can be used to produce batteries with high energy densities, high power, or both compared to batteries using electrodes of conventional design with relatively highly tortuous pores.

  15. Micromachined electrode array

    DOEpatents

    Okandan, Murat; Wessendorf, Kurt O.

    2007-12-11

    An electrode array is disclosed which has applications for neural stimulation and sensing. The electrode array, in certain embodiments, can include a plurality of electrodes each of which is flexibly attached to a common substrate using a plurality of springs to allow the electrodes to move independently. In other embodiments of the electrode array, the electrodes can be fixed to the substrate. The electrode array can be formed from a combination of bulk and surface micromachining, and can include electrode tips having an electroplated metal (e.g. platinum, iridium, gold or titanium) or a metal oxide (e.g. iridium oxide) for biocompatibility. The electrode array can be used to form a part of a neural prosthesis, and is particularly well adapted for use in an implantable retinal prosthesis.

  16. Flexible retinal electrode array

    DOEpatents

    Okandan, Murat; Wessendorf, Kurt O.; Christenson, Todd R.

    2006-10-24

    An electrode array which has applications for neural stimulation and sensing. The electrode array can include a large number of electrodes each of which is flexibly attached to a common substrate using a plurality of springs to allow the electrodes to move independently. The electrode array can be formed from a combination of bulk and surface micromachining, with electrode tips that can include an electroplated metal (e.g. platinum, iridium, gold or titanium) or a metal oxide (e.g. iridium oxide) for biocompatibility. The electrode array can be used to form a part of a neural prosthesis, and is particularly well adapted for use in an implantable retinal prosthesis where the electrodes can be tailored to provide a uniform gentle contact pressure with optional sensing of this contact pressure at one or more of the electrodes.

  17. High frequency reference electrode

    DOEpatents

    Kronberg, James W.

    1994-01-01

    A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or "halo" at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes.

  18. High frequency reference electrode

    DOEpatents

    Kronberg, J.W.

    1994-05-31

    A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or halo' at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes. 4 figs.

  19. High efficiency iron electrode and additives for use in rechargeable iron-based batteries

    DOEpatents

    Narayan, Sri R.; Prakash, G. K. Surya; Aniszfeld, Robert; Manohar, Aswin; Malkhandi, Souradip; Yang, Bo

    2017-02-21

    An iron electrode and a method of manufacturing an iron electrode for use in an iron-based rechargeable battery are disclosed. In one embodiment, the iron electrode includes carbonyl iron powder and one of a metal sulfide additive or metal oxide additive selected from the group of metals consisting of bismuth, lead, mercury, indium, gallium, and tin for suppressing hydrogen evolution at the iron electrode during charging of the iron-based rechargeable battery. An iron-air rechargeable battery including an iron electrode comprising carbonyl iron is also disclosed, as is an iron-air battery wherein at least one of the iron electrode and the electrolyte includes an organosulfur additive.

  20. Pollen tube development.

    PubMed

    Johnson, Mark A; Kost, Benedikt

    2010-01-01

    Pollen tubes grow rapidly in a strictly polarized manner as they transport male reproductive cells through female flower tissues to bring about fertilization. Vegetative pollen tube cells are an excellent model system to investigate processes underlying directional cell expansion. In this chapter, we describe materials and methods required for (1) the identification of novel factors essential for polarized cell growth through the isolation and analysis of Arabidopsis mutants with defects in pollen tube growth and (2) the detailed functional characterization of pollen tube proteins based on transient transformation and microscopic analysis of cultured tobacco pollen tubes.

  1. REACTOR COOLANT TUBE SEAL

    DOEpatents

    Morris, W.J.

    1958-12-01

    A plle-flattenlng control element and a fluid seal therefore to permit movement of the element into a liquld contnining region of a neutronlc reactor are described. The device consists of flattened, thin-walled aluminum tubing contalnlng a uniform mixture of thermal neutron absorbing material, and a number of soft rubber closures for the process tubes, having silts capable of passing the flattened elements therethrough, but effectively sealing the process tubes against fluld leaknge by compression of the rubber. The flattened tubing is sufficiently flexible to enable it to conform to the configuratlon of the annular spacing surrounding the fuel elements ln the process tubes.

  2. Bacillus aerius sp. nov., Bacillus aerophilus sp. nov., Bacillus stratosphericus sp. nov. and Bacillus altitudinis sp. nov., isolated from cryogenic tubes used for collecting air samples from high altitudes.

    PubMed

    Shivaji, S; Chaturvedi, P; Suresh, K; Reddy, G S N; Dutt, C B S; Wainwright, M; Narlikar, J V; Bhargava, P M

    2006-07-01

    Four novel bacterial strains were isolated from cryogenic tubes used to collect air samples at altitudes of 24, 28 and 41 km. The four strains, 24K(T), 28K(T), 41KF2a(T) and 41KF2b(T), were identified as members of the genus Bacillus. Phylogenetic analysis based on 16S rRNA gene sequences indicated that three of the strains, 24K(T), 28K(T) and 41KF2a(T), are very similar to one another (>98 % sequence similarity) and show a similarity of 98-99 % with Bacillus licheniformis and 98 % with Bacillus sonorensis. DNA-DNA hybridization studies showed that strains 24K(T), 28K(T) and 41KF2a(T) exhibit <70 % similarity with each other and with B. licheniformis and B. sonorensis. Differences in phenotypic and chemotaxonomic characteristics between the novel strains and B. licheniformis and B. sonorensis further confirmed that these three isolates are representatives of three separate novel species. Strain 41KF2b(T) showed 100 % 16S rRNA gene sequence similarity to Bacillus pumilus, but differed from its nearest phylogenetic neighbour in a number of phenotypic and chemotaxonomic characteristics and showed only 55 % DNA-DNA relatedness. Therefore, the four isolates represent four novel species for which the names Bacillus aerius sp. nov. (type strain, 24K(T)=MTCC 7303(T)=JCM 13348(T)), Bacillus aerophilus sp. nov. (type strain, 28K(T)=MTCC 7304(T)=JCM 13347(T)), Bacillus stratosphericus sp. nov. (type strain, 41KF2a(T)=MTCC 7305(T)=JCM 13349(T)) and Bacillus altitudinis sp. nov. (type strain, 41KF2b(T)=MTCC 7306(T)=JCM 13350(T)) are proposed.

  3. 64. Building 102, view of Klystron tube amplifier housing with ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    64. Building 102, view of Klystron tube amplifier housing with tube removed and showing waveguide entrances at top of photograph. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  4. 65. Building 102, view of Klystron tube in amplifier housing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    65. Building 102, view of Klystron tube in amplifier housing showing top of tube connecting conductors. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  5. High performance cermet electrodes

    DOEpatents

    Isenberg, Arnold O.; Zymboly, Gregory E.

    1986-01-01

    Disclosed is a method of increasing the operating cell voltage of a solid oxide electrochemical cell having metal electrode particles in contact with an oxygen-transporting ceramic electrolyte. The metal electrode is heated with the cell, and oxygen is passed through the oxygen-transporting ceramic electrolyte to the surface of the metal electrode particles so that the metal electrode particles are oxidized to form a metal oxide layer between the metal electrode particles and the electrolyte. The metal oxide layer is then reduced to form porous metal between the metal electrode particles and the ceramic electrolyte.

  6. 25. View down launch tube, showing shock absorption system. Lyon ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. View down launch tube, showing shock absorption system. Lyon - Whiteman Air Force Base, Minuteman Missile Launch Facility Trainer T-12, Northeast of Oscar-01 Missile Alert Facility, Knob Noster, Johnson County, MO

  7. 48. Bottom of shock absorber, bottom of launch tube, soda ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    48. Bottom of shock absorber, bottom of launch tube, soda bottle liter at right - Ellsworth Air Force Base, Delta Flight, Launch Facility, On County Road T512, south of Exit 116 off I-90, Interior, Jackson County, SD

  8. 71. DETAIL OF NITROGEN GAS STORAGE TANKS AND TRANSFER TUBING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    71. DETAIL OF NITROGEN GAS STORAGE TANKS AND TRANSFER TUBING ON SLC-3W LIQUID OXYGEN APRON - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  9. Non-thermal plasma for air and water remediation.

    PubMed

    Hashim, Siti Aiasah; Samsudin, Farah Nadia Dayana Binti; Wong, Chiow San; Abu Bakar, Khomsaton; Yap, Seong Ling; Mohd Zin, Mohd Faiz

    2016-09-01

    A modular typed dielectric barrier discharge (DBD) device is designed and tested for air and water remediation. The module is made of a number of DBD tubes that can be arranged in series or parallel. Each of the DBD tubes comprises inner electrode enclosed with dielectric barrier and arranged as such to provide a gap for the passage of gases. Non-thermal plasma generated in the gap effectively creates gaseous chemical reactions. Its efficacy in the remediation of gas stream containing high NOx, similar to diesel emission and wastewater containing latex, are presented. A six tubes DBD module has successfully removed more than 80% of nitric oxide from the gas stream. In another arrangement, oxygen was fed into a two tubes DBD to generate ozone for treatment of wastewater. Samples of wastewater were collected from a treatment pond of a rubber vulcanization pilot plant. The water pollution load was evaluated by the chemical oxygen demand (COD) and biological oxygen demand (BOD5) values. Preliminary results showed some improvement (about 13%) on the COD after treatment and at the same time had increased the BOD5 by 42%. This results in higher BOD5/COD ratio after ozonation which indicate better biodegradability of the wastewater.

  10. Microtitrimetry by differential electrolytic potentiometry using metallic electrodes and nanomaterials modified metallic electrodes

    NASA Astrophysics Data System (ADS)

    Amro, Abdulaziz Nabil

    For the first time silver wire electrodes have been coated with carbon nanotubes using floating catalyst chemical vapor deposition (CVD) method. The production of CNTs has been conducted in a horizontal tubular reactor. Acetylene gas was used as a carbon source. Ferrocene has been used as a catalyst precursor for the growth of CNT. Different parameters have been optimized to get a high yield of CNTs and ensure their growth on the silver electrodes using univariate method. The parameters studied include the hydrogen flow rate, acetylene flow rate, temperature of the furnace, time of the reaction and the location of the electrodes in the reactor tube. The optimum conditions for those parameters were: for hydrogen and acetylene, the flow rates were 25 mL /min and 75 mL / min respectively. The furnace temperature was found to be 700 °C and the reaction time was 15 minutes. Regarding the location of the silver wires it should be located in the first 10 cm of the front side of the tube. Scanning electron microscopy (SEM) and transition electron microscopy (TEM) have been used to characterize carbon on silver electrodes. According to the experimental results, TEM figures show that CNT produced on Silver wire is multiwall carbon nanotubes MWCNT. Silver electrodes either pure or coated with CNT were used as indicating systems in micro titration using both dc differential electrolytic potentiometry (DEP) and mark-space bias DEP techniques. All types of titrimetric reactions were investigated using different types of electrodes like Pt and gold for oxidation reduction titrations, antimony electrodes for acid base titrations, silver electrodes for precipitation titrations in addition to Ag-CNT electrodes. End points at volumes of 1 microL were determined. Different parameters were optimized like the current density, the percentage bias, the volume of the sample and the concentrations of the reactants. Microtitrimetry has been applied on several types of analytes; Ferrous

  11. Intercostal drainage tube or intracardiac drainage tube?

    PubMed Central

    Anitha, N.; Kamath, S. Ganesh; Khymdeit, Edison; Prabhu, Manjunath

    2016-01-01

    Although insertion of chest drain tubes is a common medical practice, there are risks associated with this procedure, especially when inexperienced physicians perform it. Wrong insertion of the tube has been known to cause morbidity and occasional mortality. We report a case where the left ventricle was accidentally punctured leading to near-exsanguination. This report is to highlight the need for experienced physicians to supervise the procedure and train the younger physician in the safe performance of the procedure. PMID:27397467

  12. Method of preparing a positive electrode for an electrochemical cell

    DOEpatents

    Tomczuk, Zygmunt

    1979-01-01

    A method of preparing an electrochemical cell including a metal sulfide as the positive electrode reactant and lithium alloy as the negative electrochemical reactant with an alkali metal, molten salt electrolyte is disclosed which permits the assembly to be accomplished in air. The electrode reactants are introduced in the most part as a sulfide of lithium and the positive electrode metal in a single-phase compound. For instance, Li.sub.2 FeS.sub.2 is a single-phase compound that is produced by the reaction of Li.sub.2 S and FeS. This compound is an intermediate in the positive electrode cycle from FeS.sub.2 to Fe and Li.sub.2 S. Its use minimizes volumetric changes from the assembled to the charged and discharged conditions of the electrode and minimizes electrode material interaction with air and moisture during assembly.

  13. Beyond Slurry-Cast Supercapacitor Electrodes: PAN/MWNT Heteromat-Mediated Ultrahigh Capacitance Electrode Sheets

    PubMed Central

    Lee, Jung Han; Kim, Jeong A; Kim, Ju-Myung; Lee, Sun-Young; Yeon, Sun-Hwa; Lee, Sang-Young

    2017-01-01

    Supercapacitors (SCs) have garnered considerable attention as an appealing power source for forthcoming smart energy era. An ultimate challenge facing the SCs is the acquisition of higher energy density without impairing their other electrochemical properties. Herein, we demonstrate a new class of polyacrylonitrile (PAN)/multi-walled carbon tube (MWNT) heteromat-mediated ultrahigh capacitance electrode sheets as an unusual electrode architecture strategy to address the aforementioned issue. Vanadium pentoxide (V2O5) is chosen as a model electrode material to explore the feasibility of the suggested concept. The heteromat V2O5 electrode sheets are produced through one-pot fabrication based on concurrent electrospraying (for V2O5 precursor/MWNT) and electrospinning (for PAN nanofiber) followed by calcination, leading to compact packing of V2O5 materials in intimate contact with MWNTs and PAN nanofibers. As a consequence, the heteromat V2O5 electrode sheets offer three-dimensionally bicontinuous electron (arising from MWNT networks)/ion (from spatially reticulated interstitial voids to be filled with liquid electrolytes) conduction pathways, thereby facilitating redox reaction kinetics of V2O5 materials. In addition, elimination of heavy metallic foil current collectors, in combination with the dense packing of V2O5 materials, significantly increases (electrode sheet-based) specific capacitances far beyond those accessible with conventional slurry-cast electrodes. PMID:28139765

  14. Beyond Slurry-Cast Supercapacitor Electrodes: PAN/MWNT Heteromat-Mediated Ultrahigh Capacitance Electrode Sheets

    NASA Astrophysics Data System (ADS)

    Lee, Jung Han; Kim, Jeong A.; Kim, Ju-Myung; Lee, Sun-Young; Yeon, Sun-Hwa; Lee, Sang-Young

    2017-01-01

    Supercapacitors (SCs) have garnered considerable attention as an appealing power source for forthcoming smart energy era. An ultimate challenge facing the SCs is the acquisition of higher energy density without impairing their other electrochemical properties. Herein, we demonstrate a new class of polyacrylonitrile (PAN)/multi-walled carbon tube (MWNT) heteromat-mediated ultrahigh capacitance electrode sheets as an unusual electrode architecture strategy to address the aforementioned issue. Vanadium pentoxide (V2O5) is chosen as a model electrode material to explore the feasibility of the suggested concept. The heteromat V2O5 electrode sheets are produced through one-pot fabrication based on concurrent electrospraying (for V2O5 precursor/MWNT) and electrospinning (for PAN nanofiber) followed by calcination, leading to compact packing of V2O5 materials in intimate contact with MWNTs and PAN nanofibers. As a consequence, the heteromat V2O5 electrode sheets offer three-dimensionally bicontinuous electron (arising from MWNT networks)/ion (from spatially reticulated interstitial voids to be filled with liquid electrolytes) conduction pathways, thereby facilitating redox reaction kinetics of V2O5 materials. In addition, elimination of heavy metallic foil current collectors, in combination with the dense packing of V2O5 materials, significantly increases (electrode sheet-based) specific capacitances far beyond those accessible with conventional slurry-cast electrodes.

  15. Static and dynamic analysis of a four-tube piezoelectric actuator.

    PubMed

    Ma, Yuting; Feng, Zhihua; Pan, Chengliang; Kong, Fanrang

    2009-06-01

    Piezoelectric tubes with film electrodes on their outer and inner surfaces can be used to compose multitube actuators. The actuator of four piezoelectric tubes can substitute the traditional single-tube actuator with quartered electrodes which has been widely used in scanning probe microscopy and piezoelectric motors. In this article, the static deflection, static bending moment, resonant frequency, and dynamic deflection of the four-tube actuator are all studied in detail. The comparison between this actuator and the traditional single-tube actuator is also done and the results show that the four-tube actuator has better performances under certain conditions. The experiment results of a prototype actuator testified the validation of the analysis.

  16. Pulse Tube Refrigerator

    NASA Astrophysics Data System (ADS)

    Matsubara, Yoichi

    The pulse tube refrigerator is one of the regenerative cycle refrigerators such as Stirling cycle or Gifford-McMahon cycle which gives the cooling temperature below 150 K down to liquid helium temperature. In 1963, W. E. Gifford invented a simple refrigeration cycle which is composed of compressor, regenerator and simple tube named as pulse tube which gives a similar function of the expander in Stirling or Gifford-McMahon cycle. The thermodynamically performance of this pulse tube refrigerator is inferior to that of other regenerative cycles. In 1984, however, Mikulin and coworkers made a significant advance in pulse tube configuration called as orifice pulse tube. After this, several modifications of the pulse tube hot end configuration have been developed. With those modifications, the thermodynamic performance of the pulse tube refrigerator became the same order to that of Stirling and Gifford-McMahon refrigerator. This article reviews the brief history of the pulse tube refrigerator development in the view point of its thermodynamically efficiency. Simplified theories of the energy flow in the pulse tube have also been described.

  17. FUEL CELL ELECTRODE MATERIALS

    DTIC Science & Technology

    FUEL CELL ELECTRODE MATERIALS. RAW MATERIAL SELECTION INFLUENCES POLARIZATION BUT IS NOT A SINGLE CONTROLLING FACTOR. AVAILABLE...DATA INDICATES THAT AN INTERRELATIONSHIP OF POROSITY, AVERAGE PORE VOLUME, AND PERMEABILITY CONTRIBUTES TO ELECTRODE FUEL CELL BEHAVIOR.

  18. Improved biomedical electrode

    NASA Technical Reports Server (NTRS)

    Frost, J. D., Jr.

    1972-01-01

    Newly designed electrode is prefilled, disposable, electrolyte-saturated spong. New design permits longe periods of storage without deterioration, and readiness in matter of seconds. Electrodes supply signals for electroencephalogram, electro-oculogram, and electrocardiogram.

  19. Corneal-shaping electrode

    DOEpatents

    Doss, James D.; Hutson, Richard L.

    1982-01-01

    The disclosure relates to a circulating saline electrode for changing corneal shape in eyes. The electrode comprises a tubular nonconductive electrode housing having an annular expanded base which has a surface substantially matched to a subject corneal surface. A tubular conductive electrode connected to a radiofrequency generating source is disposed within the electrode housing and longitudinally aligned therewith. The electrode has a generally hemispherical head having at least one orifice. Saline solution is circulated through the apparatus and over the cornea to cool the corneal surface while radiofrequency electric current emitted from the electrode flows therefrom through the cornea to a second electrode, on the rear of the head. This current heats the deep corneal stroma and thereby effects corneal reshaping as a biological response to the heat.

  20. The CMG Nickel Electrode

    NASA Technical Reports Server (NTRS)

    Depaul, R. A.; Gutridge, I.

    1981-01-01

    The development and design of the Controlled Microgeometry electrode are described. Advantages of the electrode over others in existance include a higher number of ampere hours per kilogram and the ability to make them over a wide range of thicknesses. The parameters that control the performance of the electrode can be individually controlled over a wide range. Therefore, the electrode may be designed to give the optimum performance for a given duty cycle.

  1. Compartmented electrode structure

    DOEpatents

    Vissers, Donald R.; Shimotake, Hiroshi; Gay, Eddie C.; Martino, Fredric J.

    1977-06-14

    Electrodes for secondary electrochemical cells are provided with compartments for containing particles of the electrode reactant. The compartments are defined by partitions that are generally impenetrable to the particles of reactant and, in some instances, to the liquid electrolyte used in the cell. During cycling of the cell, reactant material initially loaded into a particular compartment is prevented from migrating and concentrating within the lower portion of the electrode or those portions of the electrode that exhibit reduced electrical resistance.

  2. Insulated ECG electrodes

    NASA Technical Reports Server (NTRS)

    Portnoy, W. M.; David, R. M.

    1973-01-01

    Insulated, capacitively coupled electrode does not require electrolyte paste for attachment. Other features of electrode include wide range of nontoxic material that may be employed for dielectric because of sputtering technique used. Also, electrode size is reduced because there is no need for external compensating networks with FET operational amplifier.

  3. Fuel cell electrodes

    DOEpatents

    Strmcnik, Dusan; Cuesta, Angel; Stamenkovic, Vojislav; Markovic, Nenad

    2015-06-23

    A process includes patterning a surface of a platinum group metal-based electrode by contacting the electrode with an adsorbate to form a patterned platinum group metal-based electrode including platinum group metal sites blocked with adsorbate molecules and platinum group metal sites which are not blocked.

  4. Aerospace electrode line

    NASA Astrophysics Data System (ADS)

    Miller, L.

    1980-04-01

    A facility which produces electrodes for spacecraft power supplies is described. The electrode assembly procedures are discussed. A number of design features in the production process are reported including a batch operation mode and an independent equipment module design approach for transfering the electrode materials from process tank to process tank.

  5. Electrically conductive diamond electrodes

    DOEpatents

    Swain, Greg; Fischer, Anne ,; Bennett, Jason; Lowe, Michael

    2009-05-19

    An electrically conductive diamond electrode and process for preparation thereof is described. The electrode comprises diamond particles coated with electrically conductive doped diamond preferably by chemical vapor deposition which are held together with a binder. The electrodes are useful for oxidation reduction in gas, such as hydrogen generation by electrolysis.

  6. Microresonator electrode design

    DOEpatents

    Olsson, III, Roy H.; Wojciechowski, Kenneth; Branch, Darren W.

    2016-05-10

    A microresonator with an input electrode and an output electrode patterned thereon is described. The input electrode includes a series of stubs that are configured to isolate acoustic waves, such that the waves are not reflected into the microresonator. Such design results in reduction of spurious modes corresponding to the microresonator.

  7. A Simple Hydrogen Electrode

    ERIC Educational Resources Information Center

    Eggen, Per-Odd

    2009-01-01

    This article describes the construction of an inexpensive, robust, and simple hydrogen electrode, as well as the use of this electrode to measure "standard" potentials. In the experiment described here the students can measure the reduction potentials of metal-metal ion pairs directly, without using a secondary reference electrode. Measurements…

  8. Longitudinal discharge laser electrodes

    DOEpatents

    Warner, B.E.; Miller, J.L.; Ault, E.R.

    1994-08-23

    The improved longitudinal discharge laser electrode with IR baffle includes an electrode made up of washers spaced along the laser axis in order to form inter-washer spaces for hollow cathode discharge to take place and for IR radiation to be trapped. Additional IR baffles can be placed between the electrode ann the window. 2 figs.

  9. Longitudinal discharge laser electrodes

    DOEpatents

    Warner, Bruce E.; Miller, John L.; Ault, Earl R.

    1994-01-01

    The improved longitudinal discharge laser electrode with IR baffle includes an electrode made up of washers spaced along the laser axis in order to form inter-washer spaces for hollow cathode discharge to take place and for IR radiation to be trapped. Additional IR baffles can be placed between the electrode ann the window.

  10. Lunar Lava Tube Sensing

    NASA Technical Reports Server (NTRS)

    York, Cheryl Lynn; Walden, Bryce; Billings, Thomas L.; Reeder, P. Douglas

    1992-01-01

    Large (greater than 300 m diameter) lava tube caverns appear to exist on the Moon and could provide substantial safety and cost benefits for lunar bases. Over 40 m of basalt and regolith constitute the lava tube roof and would protect both construction and operations. Constant temperatures of -20 C reduce thermal stress on structures and machines. Base designs need not incorporate heavy shielding, so lightweight materials can be used and construction can be expedited. Identification and characterization of lava tube caverns can be incorporated into current precursor lunar mission plans. Some searches can even be done from Earth. Specific recommendations for lunar lava tube search and exploration are (1) an Earth-based radar interferometer, (2) an Earth-penetrating radar (EPR) orbiter, (3) kinetic penetrators for lunar lava tube confirmation, (4) a 'Moon Bat' hovering rocket vehicle, and (5) the use of other proposed landers and orbiters to help find lunar lava tubes.

  11. Electrode Nanostructures in Lithium‐Based Batteries

    PubMed Central

    Mahmood, Nasir

    2014-01-01

    Lithium‐based batteries possessing energy densities much higher than those of the conventional batteries belong to the most promising class of future energy devices. However, there are some fundamental issues related to their electrodes which are big roadblocks in their applications to electric vehicles (EVs). Nanochemistry has advantageous roles to overcome these problems by defining new nanostructures of electrode materials. This review article will highlight the challenges associated with these chemistries both to bring high performance and longevity upon considering the working principles of the various types of lithium‐based (Li‐ion, Li‐air and Li‐S) batteries. Further, the review discusses the advantages and challenges of nanomaterials in nanostructured electrodes of lithium‐based batteries, concerns with lithium metal anode and the recent advancement in electrode nanostructures. PMID:27980896

  12. Electrode Nanostructures in Lithium-Based Batteries.

    PubMed

    Mahmood, Nasir; Hou, Yanglong

    2014-12-01

    Lithium-based batteries possessing energy densities much higher than those of the conventional batteries belong to the most promising class of future energy devices. However, there are some fundamental issues related to their electrodes which are big roadblocks in their applications to electric vehicles (EVs). Nanochemistry has advantageous roles to overcome these problems by defining new nanostructures of electrode materials. This review article will highlight the challenges associated with these chemistries both to bring high performance and longevity upon considering the working principles of the various types of lithium-based (Li-ion, Li-air and Li-S) batteries. Further, the review discusses the advantages and challenges of nanomaterials in nanostructured electrodes of lithium-based batteries, concerns with lithium metal anode and the recent advancement in electrode nanostructures.

  13. Breathing zone air sampler

    DOEpatents

    Tobin, John

    1989-01-01

    A sampling apparatus is provided which comprises a sampler for sampling air in the breathing zone of a wearer of the apparatus and a support for the sampler preferably in the form of a pair of eyeglasses. The sampler comprises a sampling assembly supported on the frame of the eyeglasses and including a pair of sample transport tubes which are suspended, in use, centrally of the frame so as to be disposed on opposite sides of the nose of the wearer and which each include an inlet therein that, in use, is disposed adjacent to a respective nostril of the nose of the wearer. A filter holder connected to sample transport tubes supports a removable filter for filtering out particulate material in the air sampled by the apparatus. The sample apparatus is connected to a pump for drawing air into the apparatus through the tube inlets so that the air passes through the filter.

  14. Breathing zone air sampler

    SciTech Connect

    Tobin, J.

    1989-08-22

    A sampling apparatus is presented which comprises a sampler for sampling air in the breathing zone of a wearer of the apparatus and a support for the sampler preferably in the form of a pair of eyeglasses. The sampler comprises a sampling assembly supported on the frame of the eyeglasses and including a pair of sample transport tubes which are suspended, in use, centrally of the frame so as to be disposed on opposite sides of the nose of the wearer and which each include an inlet therein that, in use, is disposed adjacent to a respective nostril of the nose of the wearer. A filter holder connected to sample transport tubes supports a removable filter for filtering out particulate material in the air sampled by the apparatus. The sample apparatus is connected to a pump for drawing air into the apparatus through the tube inlets so that the air passes through the filter.

  15. Conduction cooled tube supports

    DOEpatents

    Worley, Arthur C.; Becht, IV, Charles

    1984-01-01

    In boilers, process tubes are suspended by means of support studs that are in thermal contact with and attached to the metal roof casing of the boiler and the upper bend portions of the process tubes. The support studs are sufficiently short that when the boiler is in use, the support studs are cooled by conduction of heat to the process tubes and the roof casing thereby maintaining the temperature of the stud so that it does not exceed 1400.degree. F.

  16. Programming DNA tube circumferences.

    PubMed

    Yin, Peng; Hariadi, Rizal F; Sahu, Sudheer; Choi, Harry M T; Park, Sung Ha; Labean, Thomas H; Reif, John H

    2008-08-08

    Synthesizing molecular tubes with monodisperse, programmable circumferences is an important goal shared by nanotechnology, materials science, and supermolecular chemistry. We program molecular tube circumferences by specifying the complementarity relationships between modular domains in a 42-base single-stranded DNA motif. Single-step annealing results in the self-assembly of long tubes displaying monodisperse circumferences of 4, 5, 6, 7, 8, 10, or 20 DNA helices.

  17. Ruggedized electronographic tube development

    NASA Technical Reports Server (NTRS)

    Nevin, S.

    1981-01-01

    Because of their glass components and lack of far ultraviolet sensitivity, currently available Spectracons are not suited for rocket launch. Technology developed for second generation image tubes and for magnetically focused image tubes can be applied to improve the optical and mechanical properties of these magnetically focused electronographic tubes whose 40 kilovolt signal electrons exit a 4-micrometer thick mica window and penetrate a photographic recording emulsion.

  18. Retrograde gastrojejunostomy tube migration.

    PubMed

    Adesina, Adeleke; Rammohan, Guhan; Jeanmonod, Rebecca

    2014-01-01

    Percutaneous enteral feeding tubes are placed about 250,000 times each year in the United States. Although they are relatively safe, their placement may be complicated by perforation, infection, bleeding, vomiting, dislodgment, and obstruction. There have been numerous reports of antegrade migration of gastrojejunostomy (G-J) tubes. We report a case of G-J tube regurgitation following protracted vomiting and discuss the management of this very rare entity.

  19. COAXIAL TUBE COUPLING

    DOEpatents

    Niemoth, H.R.

    1963-02-26

    BS>This patent shows a device for quickly coupling coaxial tubes in metal-to-metal fashion, so as to be suitable for use in a nuclear reactor. A threaded coliar urges a tapered metal extension on the outer coaxial tube into a tapered seat in the device and simultaneously exerts pressure through a coaxial helical spring so that a similar extension on the inner tube seats in a similar seat near the other end. (AEC)

  20. TUBE SPLITTING APPARATUS

    DOEpatents

    Frantz, C.E.; Cawley, W.E.

    1961-05-01

    A tool is described for cutting a coolant tube adapted to contain fuel elements to enable the tube to be removed from a graphite moderator mass. The tool splits the tube longitudinally into halves and curls the longitudinal edges of the halves inwardly so that they occupy less space and can be moved radially inwardly away from the walls of the hole in the graphite for easy removal from the graphite.

  1. Premixed flame propagation in vertical tubes

    NASA Astrophysics Data System (ADS)

    Kazakov, Kirill A.

    2016-04-01

    Analytical treatment of the premixed flame propagation in vertical tubes with smooth walls is given. Using the on-shell flame description, equations for a quasi-steady flame with a small but finite front thickness are obtained and solved numerically. It is found that near the limits of inflammability, solutions describing upward flame propagation come in pairs having close propagation speeds and that the effect of gravity is to reverse the burnt gas velocity profile generated by the flame. On the basis of these results, a theory of partial flame propagation driven by a strong gravitational field is developed. A complete explanation is given of the intricate observed behavior of limit flames, including dependence of the inflammability range on the size of the combustion domain, the large distances of partial flame propagation, and the progression of flame extinction. The role of the finite front-thickness effects is discussed in detail. Also, various mechanisms governing flame acceleration in smooth tubes are identified. Acceleration of methane-air flames in open tubes is shown to be a combined effect of the hydrostatic pressure difference produced by the ambient cold air and the difference of dynamic gas pressure at the tube ends. On the other hand, a strong spontaneous acceleration of the fast methane-oxygen flames at the initial stage of their evolution in open-closed tubes is conditioned by metastability of the quasi-steady propagation regimes. An extensive comparison of the obtained results with the experimental data is made.

  2. Fluidized bed heat exchanger utilizing angularly extending heat exchange tubes

    DOEpatents

    Talmud, Fred M.; Garcia-Mallol, Juan-Antonio

    1980-01-01

    A fluidized bed heat exchanger in which air is passed through a bed of particulate material containing fuel disposed in a housing. A steam/water natural circulation system is provided and includes a steam drum disposed adjacent the fluidized bed and a series of tubes connected at one end to the steam drum. A portion of the tubes are connected to a water drum and in the path of the air and the gaseous products of combustion exiting from the bed. Another portion of the tubes pass through the bed and extend at an angle to the upper surface of the bed.

  3. Sapphire tube pressure vessel

    SciTech Connect

    Outwater, J.O.

    2000-05-23

    A pressure vessel is provided for observing corrosive fluids at high temperatures and pressures. A transparent Teflon bag contains the corrosive fluid and provides an inert barrier. The Teflon bag is placed within a sapphire tube, which forms a pressure boundary. The tube is received within a pipe including a viewing window. The combination of the Teflon bag, sapphire tube and pipe provides a strong and inert pressure vessel. In an alternative embodiment, tie rods connect together compression fittings at opposite ends of the sapphire tube.

  4. Composite Pulse Tube

    NASA Technical Reports Server (NTRS)

    Martin, Jerry L.; Cloyd, Jason H.

    2007-01-01

    A modification of the design of the pulse tube in a pulse-tube cryocooler reduces axial thermal conductance while preserving radial thermal conductance. It is desirable to minimize axial thermal conductance in the pulse-tube wall to minimize leakage of heat between the warm and cold ends of the pulse tube. At the same time, it is desirable to maximize radial thermal conductance at the cold end of the pulse tube to ensure adequate thermal contact between (1) a heat exchanger in the form of a stack of copper screens inside the pulse tube at the cold end and (2) the remainder of the cold tip, which is the object to which the heat load is applied and from which heat must be removed. The modified design yields a low-heat-leak pulse tube that can be easily integrated with a cold tip. A typical pulse tube of prior design is either a thin-walled metal tube or a metal tube with a nonmetallic lining. It is desirable that the outer surface of a pulse tube be cylindrical (in contradistinction to tapered) to simplify the design of a regenerator that is also part of the cryocooler. Under some conditions, it is desirable to taper the inner surface of the pulse tube to reduce acoustic streaming. The combination of a cylindrical outer surface and a tapered inner surface can lead to unacceptably large axial conduction if the pulse tube is made entirely of metal. Making the pulse-tube wall of a nonmetallic, lowthermal- conductivity material would not solve the problem because the wall would not afford the needed thermal contact for the stack of screens in the cold end. The modified design calls for fabricating the pulse tube in two parts: a longer, nonmetallic part that is tapered on the inside and cylindrical on the outside and a shorter, metallic part that is cylindrical on both the inside and the outside. The nonmetallic part can be made from G-10 fiberglass-reinforced epoxy or other low-thermal-conductivity, cryogenically compatible material. The metallic part must have high

  5. Wound tube heat exchanger

    DOEpatents

    Ecker, Amir L.

    1983-01-01

    What is disclosed is a wound tube heat exchanger in which a plurality of tubes having flattened areas are held contiguous adjacent flattened areas of tubes by a plurality of windings to give a double walled heat exchanger. The plurality of windings serve as a plurality of effective force vectors holding the conduits contiguous heat conducting walls of another conduit and result in highly efficient heat transfer. The resulting heat exchange bundle is economical and can be coiled into the desired shape. Also disclosed are specific embodiments such as the one in which the tubes are expanded against their windings after being coiled to insure highly efficient heat transfer.

  6. Sapphire tube pressure vessel

    DOEpatents

    Outwater, John O.

    2000-01-01

    A pressure vessel is provided for observing corrosive fluids at high temperatures and pressures. A transparent Teflon bag contains the corrosive fluid and provides an inert barrier. The Teflon bag is placed within a sapphire tube, which forms a pressure boundary. The tube is received within a pipe including a viewing window. The combination of the Teflon bag, sapphire tube and pipe provides a strong and inert pressure vessel. In an alternative embodiment, tie rods connect together compression fittings at opposite ends of the sapphire tube.

  7. Fuel nozzle tube retention

    DOEpatents

    Cihlar, David William; Melton, Patrick Benedict

    2017-02-28

    A system for retaining a fuel nozzle premix tube includes a retention plate and a premix tube which extends downstream from an outlet of a premix passage defined along an aft side of a fuel plenum body. The premix tube includes an inlet end and a spring support feature which is disposed proximate to the inlet end. The premix tube extends through the retention plate. The spring retention feature is disposed between an aft side of the fuel plenum and the retention plate. The system further includes a spring which extends between the spring retention feature and the retention plate.

  8. Eustachian tube evaluation in aviators.

    PubMed

    Iannella, Giannicola; Lucertini, Marco; Pasquariello, Benedetta; Manno, Alessandra; Angeletti, Diletta; Re, Massimo; Magliulo, Giuseppe

    2017-01-01

    The aim of the study is to evaluate the Eustachian tube functionality in a group of aviators to underline a subclinical dysfunction and the related risk of ear fullness or barotitis. Hypobaric chamber allows to simulate the pressure variation of the flight. This prospective study enrolled 42 aviation pilots, members of the Italian Air Force, to whom were evaluated Eustachian tube functionality by Tubomanometry, patients subjective assessments concerning feasibility of Valsalva's and Toynbee's clinical symptoms, tympanometry, and objective Valsalva before and after exposure to hypobaric chamber. The new Eustachian tube score (ETS-7) was also calculated for each pilot before and after exposure to hypobaric chamber. Results of our examination showed that: before chamber exposition, in 92.8 % of pilots, an ETS-7 of eight or more was found bilaterally. In three (7.2 %) cases, a unilateral ETS-7 ≤ 7 was found and two of those had a positive history. After undergoing the hypobaric chamber session, the evaluation of ETS-7 showed only 19 % of pilots with an ETD score ≤7, in particular three bilateral and five unilateral cases. Three of those pilots were clinically positive: two airmen reported persistent fullness, while the other one had a barotitis. Therefore, the combined use of TMM and ETS-7 before and after hypobaric chamber exposure appears to be a reliable method for assessing the functional capacity of the Eustachian tube in aviators, the stressful effect of flight on it, to exclude subjects at increased risk of ear pain, fullness, or barotrauma.

  9. Combustor cap having non-round outlets for mixing tubes

    SciTech Connect

    Hughes, Michael John; Boardman, Gregory Allen; McConnaughhay, Johnie Franklin; Arguinzoni, Carlo Antonio

    2016-12-27

    A system includes a a combustor cap configured to be coupled to a plurality of mixing tubes of a multi-tube fuel nozzle, wherein each mixing tube of the plurality of mixing tubes is configured to mix air and fuel to form an air-fuel mixture. The combustor cap includes multiple nozzles integrated within the combustor cap. Each nozzle of the multiple nozzles is coupled to a respective mixing tube of the multiple mixing tubes. In addition, each nozzle of the multiple nozzles includes a first end and a second end. The first end is coupled to the respective mixing tube of the multiple mixing tubes. The second end defines a non-round outlet for the air-fuel mixture. Each nozzle of the multiple nozzles includes an inner surface having first and second portions, the first portion radially diverges along an axial direction from the first end to the second end, and the second portion radially converges along the axial direction from the first end to the second end.

  10. Air-cooled, hydrogen-air fuel cell

    NASA Technical Reports Server (NTRS)

    Shelekhin, Alexander B. (Inventor); Bushnell, Calvin L. (Inventor); Pien, Michael S. (Inventor)

    1999-01-01

    An air-cooled, hydrogen-air solid polymer electrolyte (SPE) fuel cell with a membrane electrode assembly operatively associated with a fluid flow plate having at least one plate cooling channel extending through the plate and at least one air distribution hole extending from a surface of the cathode flow field into the plate cooling channel.

  11. Negative electrode composition

    DOEpatents

    Kaun, Thomas D.; Chilenskas, Albert A.

    1982-01-01

    A secondary electrochemical cell and a negative electrode composition for use therewith comprising a positive electrode containing an active material of a chalcogen or a transiton metal chalcogenide, a negative electrode containing a lithium-aluminum alloy and an amount of a ternary alloy sufficient to provide at least about 5 percent overcharge capacity relative to a negative electrode solely of the lithium-aluminum alloy, the ternary alloy comprising lithium, aluminum, and iron or cobalt, and an electrolyte containing lithium ions in contact with both of the positive and the negative electrodes. The ternary alloy is present in the electrode in the range of from about 5 percent to about 50 percent by weight of the electrode composition and may include lithium-aluminum-nickel alloy in combination with either the ternary iron or cobalt alloys. A plurality of series connected cells having overcharge capacity can be equalized on the discharge side without expensive electrical equipment.

  12. Igniter electrode life control

    SciTech Connect

    Scott, J.C.

    1985-10-07

    The prevention of electrode material erosion by undercutting in the outer electrode shell of igniter electrodes of jet engine ignition systems is prevented by the application of an electrical insulation coating. The coating is applied to the surface of the outer electrode shell which faces the ceramic insulation around the center electrode where erosion patterns are known to occur. The insulation material is selected from electrical insulation substances such as oxides of aluminum, tungsten, magnesium, beryllium or zirconium by choosing a non-porous electrical-insulating substance with thermal-expansion characteristics approximately equalling those of the outer electrode shell. Since a typical outer electrode shell is composed of 446 stainless steel, an optimum choice for the electrical insulation coating is Al/sub 2/O/sub 3/ deposited with a coating thickness of between 5 and 10 mils.

  13. Steam generator tube failures

    SciTech Connect

    MacDonald, P.E.; Shah, V.N.; Ward, L.W.; Ellison, P.G.

    1996-04-01

    A review and summary of the available information on steam generator tubing failures and the impact of these failures on plant safety is presented. The following topics are covered: pressurized water reactor (PWR), Canadian deuterium uranium (CANDU) reactor, and Russian water moderated, water cooled energy reactor (VVER) steam generator degradation, PWR steam generator tube ruptures, the thermal-hydraulic response of a PWR plant with a faulted steam generator, the risk significance of steam generator tube rupture accidents, tubing inspection requirements and fitness-for-service criteria in various countries, and defect detection reliability and sizing accuracy. A significant number of steam generator tubes are defective and are removed from service or repaired each year. This wide spread damage has been caused by many diverse degradation mechanisms, some of which are difficult to detect and predict. In addition, spontaneous tube ruptures have occurred at the rate of about one every 2 years over the last 20 years, and incipient tube ruptures (tube failures usually identified with leak detection monitors just before rupture) have been occurring at the rate of about one per year. These ruptures have caused complex plant transients which have not always been easy for the reactor operators to control. Our analysis shows that if more than 15 tubes rupture during a main steam line break, the system response could lead to core melting. Although spontaneous and induced steam generator tube ruptures are small contributors to the total core damage frequency calculated in probabilistic risk assessments, they are risk significant because the radionuclides are likely to bypass the reactor containment building. The frequency of steam generator tube ruptures can be significantly reduced through appropriate and timely inspections and repairs or removal from service.

  14. Chemical Dosimeter Tube With Coaxial Sensing Rod

    NASA Technical Reports Server (NTRS)

    Lueck, Dale E.

    1993-01-01

    Improved length-of-stain (LOS) chemical dosimeter indicates total dose of chemical vapor in air. Made with rods and tubes of various diameters to obtain various sensitivities and dynamic ranges. Sensitivity larger and dose range smaller when more room for diffusion in gap between tube and rod. Offers greater resistance to changing of color of exposed dye back to color of unexposed condition, greater sensitivity, and higher degree of repeatability. Developed to measure doses of gaseous HCI, dosimeter modified by use of other dyes to indicate doses of other chemical vapors.

  15. Pulse tube coolers for Meteosat third generation

    SciTech Connect

    Butterworth, James; Aigouy, Gérald; Chassaing, Clement; Debray, Benoît; Huguet, Alexandre

    2014-01-29

    Air Liquide's Large Pulse Tube Coolers (LPTC) will be used to cool the focal planes of the Infrared Sounder (IRS) and Flexible Combined Imager (FCI) instruments aboard the ESA/Eumetsat satellites Meteosat Third Generation (MTG). This cooler consists of an opposed piston linear compressor driving a pulse tube cold head and the associated drive electronics including temperature regulation and vibration cancellation algorithms. Preparations for flight qualification of the cooler are now underway. In this paper we present results of the optimization and qualification activities as well as an update on endurance testing.

  16. Electrode fabrication for high-speed polarization mode converter

    NASA Astrophysics Data System (ADS)

    Meng, X.; Zhang, S.; Chen, C.; Poirier, M.; Shepherd, F. R.; Das, S. R.

    2004-05-01

    As part of the development of a traveling wave polarization converter (TWPC), a technique for producing ``T-electrodes'' adjacent to the ridge sidewalls and air bridges has been developed. To maximize the conversion efficiency, the rf electrodes on the etched floor are required to be very close to the ridge sidewalls. In the fabrication of the electrode, patterned seed layer stripes were first put on the etched floor on both sides of the waveguide by a metal lift-off process. Onto this seed layer, the T-electrode was electroplated through a patterned thick photoresist. After resist removal, the unwanted seed layer was stripped off by chemical etch back. Through this multistep process, the electrodes were constructed successfully with the desired proximity to the ridge waveguide. For easy chip assembly, the bond pads were designed to be on the same side of the device. Two long and wide metal air bridges over the ridge waveguide were made to connect the electrode on one side to the bond pads on the other side of the ridge. It was found that the air bridges were easily damaged in the bonding process prior to lap and polish because of the particular device structure, i.e., air bridges being the highest point of the wafer and only a small number of air bridges on the wafer. To protect the air bridge a patterned photoresist layer was applied before the wafer was bonded to a carrier. .

  17. Preliminary design of an air solar collector

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Report containing performance specifications and engineering drawings of concentric-tube air solar collector show details of collector and subcomponents that indicate efficiency surpassing predetermined performance baseline for air collectors.

  18. Parametric Study of High Frequency Pulse Detonation Tubes

    NASA Technical Reports Server (NTRS)

    Cutler, Anderw D.

    2008-01-01

    This paper describes development of high frequency pulse detonation tubes similar to a small pulse detonation engine (PDE). A high-speed valve injects a charge of a mixture of fuel and air at rates of up to 1000 Hz into a constant area tube closed at one end. The reactants detonate in the tube and the products exit as a pulsed jet. High frequency pressure transducers are used to monitor the pressure fluctuations in the device and thrust is measured with a balance. The effects of injection frequency, fuel and air flow rates, tube length, and injection location are considered. Both H2 and C2H4 fuels are considered. Optimum (maximum specific thrust) fuel-air compositions and resonant frequencies are identified. Results are compared to PDE calculations. Design rules are postulated and applications to aerodynamic flow control and propulsion are discussed.

  19. Method for shaping polyethylene tubing

    NASA Technical Reports Server (NTRS)

    Kramer, R. C.

    1981-01-01

    Method forms polyethylene plastic tubing into configurations previously only possible with metal tubing. By using polyethylene in place of copper or stain less steel tubing inlow pressure systems, fabrication costs are significantly reduced. Polyethylene tubing can be used whenever low pressure tubing is needed in oil operations, aircraft and space applications, powerplants, and testing laboratories.

  20. Pyrotechnic Tubing Connector

    NASA Technical Reports Server (NTRS)

    Graves, Thomas J.; Yang, Robert A.

    1988-01-01

    Tool forms mechanical seal at joint without levers or hydraulic apparatus. Proposed tool intended for use in outer space used on Earth by heavily garbed workers to join tubing in difficult environments. Called Pyrotool, used with Lokring (or equivalent) fittings. Piston slides in cylinder when pushed by gas from detonating pyrotechnic charge. Impulse of piston compresses fittings, sealing around butting ends of tubes.

  1. Plasma bullets behavior in a tube covered by a conductor

    SciTech Connect

    Xian, Y. B.; Xu, H. T.; Lu, X. P. Pei, X. K.; Gong, W. W.; Lu, Y.; Liu, D. W.; Yang, Y.

    2015-06-15

    In this work, for better applications of atmospheric pressure plasma jets, the physics of plasma streamers in a glass tube with a part of it covered by a conductor is investigated. To better understand the propagation mechanism of plasma bullets in capillary tubes passing through a curved or narrow passage for some biomedical or material applications, the propagation of plasma streamers in a tube covered by a floating conductor is investigated. For a plasma streamer propagating in a tube covered by a conductor, the plasma streamer is suppressed and becomes shorter, and a secondary streamer is generated in the tube at the downstream end of the conductor. The larger the area covered by the conductor, or the thinner the tube, the stronger the plasma streamer is inhibited. The electric potential of the conductor is measured to be as high as 6 kV. On the other hand, a higher voltage applied on the HV electrode, or a higher gas flow rate will make the secondary plasma streamer longer. It is found that the capacitor formed by the conductor outside the tube and the wall of the tube plays an important role in inhibiting the original plasma streamer and generating the secondary streamer. Moreover, the active species generated by the original plasma play important role in generating a secondary plasma streamer.

  2. Fallopian Tube Catheterization

    PubMed Central

    Thurmond, Amy Suzanne

    2013-01-01

    Fallopian tube catheterization is used for treatment of infertility caused by proximal tubal occlusion, and has replaced surgical treatment for this condition. More recently, fallopian tube catheterization has been used for tubal sterilization. Interventional radiologists tested numerous methods for tubal occlusion using the rabbit as an animal model. As a result, a tubal device has recently been Food and Drug Administration approved for permanent sterilization using hysteroscopic guidance; it can also be placed fluoroscopically by fallopian tube catheterization as an “off-label” procedure. This is a 5-year continuation and update on a procedure that has been done by interventional radiologists for 25 years; history of the development of fallopian tube catheterization in women has been published in detail in this journal. Highlighted in this article will be description of the basic components needed for fallopian tube catheterization. PMID:24436565

  3. Supply Chain Viability for the North American Microwave Power Tube Industry

    DTIC Science & Technology

    2007-11-02

    Sponsored by DTIC Supply Chain Viability for the North American Microwave Power Tube Industry Supply Chain Viability for the US Microwave Power Tube...Industry iii Supply Chain Viability for the North American Microwave Power Tube Industry September 2002 Therese M. Philippi Federico M. Sciammarella...Patterson Air Force Base 45433-7739 Supply Chain Viability for the US Microwave Power Tube Industry ii REPORT DOCUMENTATION PAGE Form Approved Public

  4. Pneumatic vacuum tube message center, basement room 23, looking southeast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Pneumatic vacuum tube message center, basement room 23, looking southeast toward doorway and corridor. Note soundproof walls, pedestal flooring, and cable tray suspended from the ceiling - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  5. Uncharged positive electrode composition

    DOEpatents

    Kaun, Thomas D.; Vissers, Donald R.; Shimotake, Hiroshi

    1977-03-08

    An uncharged positive-electrode composition contains particulate lithium sulfide, another alkali metal or alkaline earth metal compound other than sulfide, e.g., lithium carbide, and a transition metal powder. The composition along with a binder, such as electrolytic salt or a thermosetting resin is applied onto an electrically conductive substrate to form a plaque. The plaque is assembled as a positive electrode within an electrochemical cell opposite to a negative electrode containing a material such as aluminum or silicon for alloying with lithium. During charging, lithium alloy is formed within the negative electrode and transition metal sulfide such as iron sulfide is produced within the positive electrode. Excess negative electrode capacity over that from the transition metal sulfide is provided due to the electrochemical reaction of the other than sulfide alkali metal or alkaline earth metal compound.

  6. Solid sorbent air sampler

    NASA Astrophysics Data System (ADS)

    Galen, T. J.

    1986-04-01

    A fluid sampler for collecting a plurality of discrete samples over separate time intervals is described. The sampler comprises a sample assembly having an inlet and a plurality of discreet sample tubes each of which has inlet and outlet sides. A multiport dual acting valve is provided in the sampler in order to sequentially pass air from the sample inlet into the selected sample tubes. The sample tubes extend longitudinally of the housing and are located about the outer periphery thereof so that upon removal of an enclosure cover, they are readily accessible for operation of the sampler in an analysis mode.

  7. Solid sorbent air sampler

    NASA Technical Reports Server (NTRS)

    Galen, T. J. (Inventor)

    1986-01-01

    A fluid sampler for collecting a plurality of discrete samples over separate time intervals is described. The sampler comprises a sample assembly having an inlet and a plurality of discreet sample tubes each of which has inlet and outlet sides. A multiport dual acting valve is provided in the sampler in order to sequentially pass air from the sample inlet into the selected sample tubes. The sample tubes extend longitudinally of the housing and are located about the outer periphery thereof so that upon removal of an enclosure cover, they are readily accessible for operation of the sampler in an analysis mode.

  8. Velocity Estimate Following Air Data System Failure

    DTIC Science & Technology

    2008-03-01

    12 Figure 2.2. Pitot Tube...that relay pitot -static information from the aircraft’s air data system and inertial measurement information from the Inertial Navigation System...Air data systems receive total and static pressure inputs from a pitot -static system. A typical pitot tube, as shown below, receives total pressure

  9. Nanoscopic electrode molecular probes

    DOEpatents

    Krstic, Predrag S [Knoxville, TN; Meunier, Vincent [Knoxville, TN

    2012-05-22

    The present invention relates to a method and apparatus for enhancing the electron transport property measurements of a molecule when the molecule is placed between chemically functionalized carbon-based nanoscopic electrodes to which a suitable voltage bias is applied. The invention includes selecting a dopant atom for the nanoscopic electrodes, the dopant atoms being chemically similar to atoms present in the molecule, and functionalizing the outer surface and terminations of the electrodes with the dopant atoms.

  10. [Enteral tube feeding].

    PubMed

    Haller, Alois

    2014-03-01

    Tube feeding is an integral part of medical therapies, and can be easily managed also in the outpatient setting. Tube feeding by the stomach or small intestine with nasogastral or nasojejunal tubes is common in clinical practice. Long-term nutrition is usually provided through a permanent tube, i. e. a percutaneous endoscopic gastrostomy (PEG). Modern portable nutrition pumps are used to cover the patient's nutritional needs. Enteral nutrition is always indicated if patients can not or should not eat or if nutritional requirements cannot be covered within 3 days after an intervention, e. g. after abdominal surgery. Industrially produced tube feedings with defined substrate concentrations are being used; different compositions of nutrients, such as glutamine fish oil etc., are used dependent on the the condition of the patient. Enteral nutrition may be associated with complications of the tube, e. g. dislocation, malposition or obstruction, as well as the feeding itself, e. g.hyperglycaemia, electrolyte disturbances, refeeding syndrome diarrhea or aspiration). However, the benefit of tube feeding usually exceeds the potential harm substantially.

  11. Pocket ECG electrode

    NASA Technical Reports Server (NTRS)

    Lund, Gordon F. (Inventor)

    1982-01-01

    A low-noise electrode suited for sensing electrocardiograms when chronically and subcutaneously implanted in a free-ranging subject. The electrode comprises a pocket-shaped electrically conductive member with a single entrance adapted to receive body fluids. The exterior of the member and the entrance region is coated with electrical insulation so that the only electrolyte/electrode interface is within the member remote from artifact-generating tissue. Cloth straps are bonded to the member to permit the electrode to be sutured to tissue and to provide electrical lead flexure relief.

  12. Pocket ECG electrode

    NASA Technical Reports Server (NTRS)

    Lund, G. F. (Inventor)

    1980-01-01

    A low noise electrode suited for sensing electrocardiograms when chronically and subcutaneously implanted in a free ranging subject is described. The electrode comprises a pocket shaped electrically conductive member with a single entrance adapted to receive body fluids. The exterior of the member and the entrance region is coated with electrical insulation so that the only electrolyte/electrode interface is within the member, remote from artifact-generating tissue. Cloth straps are bonded to the member to permit the electrode to be sutured to tissue and to provide electrical lead flexure relief.

  13. The effect of voltage waveform and tube diameter on transporting cold plasma strings through a flexible dielectric tube

    SciTech Connect

    Sohbatzadeh, Farshad; Omran, Azadeh Valinataj

    2014-11-15

    In this work, we developed transporting atmospheric pressure cold plasma using single electrode configuration through a sub-millimetre flexible dielectric tube beyond 100 cm. It was shown that the waveform of the applied high voltage is essential for controlling upstream and downstream plasma inside the tube. In this regard, sawtooth waveform enabled the transport of plasma with less applied high voltage compared to sinusoidal and pulsed form voltages. A cold plasma string as long as 130 cm was obtained by only 4 kV peak-to-peak sawtooth high voltage waveform. Optical emission spectroscopy revealed that reactive chemical species, such as atomic oxygen and hydroxyl, are generated at the tube exit. The effect of tube diameter on the transported plasma was also examined: the smaller the diameter, the higher the applied voltage. The device is likely to be used for sterilization, decontamination, and therapeutic endoscopy as already suggested by other groups in recent past years.

  14. Effects of Fuel Distribution on Detonation Tube Performance

    NASA Technical Reports Server (NTRS)

    Perkins, Hugh Douglas

    2002-01-01

    A pulse detonation engine (PDE) uses a series of high frequency intermittent detonation tubes to generate thrust. The process of filling the detonation tube with fuel and air for each cycle may yield non-uniform mixtures. Lack of mixture uniformity is commonly ignored when calculating detonation tube thrust performance. In this study, detonation cycles featuring idealized non-uniform H2/air mixtures were analyzed using the SPARK two-dimensional Navier-Stokes CFD code with 7-step H2/air reaction mechanism. Mixture non-uniformities examined included axial equivalence ratio gradients, transverse equivalence ratio gradients, and partially fueled tubes. Three different average test section equivalence ratios (phi), stoichiometric (phi = 1.00), fuel lean (phi = 0.90), and fuel rich (phi = 1.10), were studied. All mixtures were detonable throughout the detonation tube. It was found that various mixtures representing the same test section equivalence ratio had specific impulses within 1 percent of each other, indicating that good fuel/air mixing is not a prerequisite for optimal detonation tube performance.

  15. Snorkeling and Jones tubes.

    PubMed

    Lam, Lewis Y W; Weatherhead, Robert G

    2015-01-01

    We report a case of tympanic membrane rupture during snorkeling in a 17-year-old young man who had previously undergone bilateral Jones tubes placed for epiphora. To our knowledge, this phenomenon has not been previously reported.

  16. Enteral nutrition by tube.

    PubMed

    Armstrong, P J; Hand, M S; Frederick, G S

    1990-01-01

    When oral intake is unsatisfactory or contraindicated, maintenance of nutrition by tube feeding is an alternative to the parenteral route. A large volume of research data supports the decision to use the enteral route whenever possible. Entry of food into the alimentary tract is a stimulus to structural and functional maintenance of that tract. Enteral nutrition can be given via indwelling nasoesophageal, pharyngostomy, esophagostomy, percutaneous or surgical gastrostomy, or enterostomy tube. Use of an appropriate catheter, familiarity with the technique used, and careful patient selection and monitoring are important factors in successful tube feeding. Blenderized pet food diets should be fed whenever possible; commercially available liquid diets provide an alternative when tube caliber or patient factors preclude the use of blenderized foods.

  17. Tube-Forming Assays.

    PubMed

    Brown, Ryan M; Meah, Christopher J; Heath, Victoria L; Styles, Iain B; Bicknell, Roy

    2016-01-01

    Angiogenesis involves the generation of new blood vessels from the existing vasculature and is dependent on many growth factors and signaling events. In vivo angiogenesis is dynamic and complex, meaning assays are commonly utilized to explore specific targets for research into this area. Tube-forming assays offer an excellent overview of the molecular processes in angiogenesis. The Matrigel tube forming assay is a simple-to-implement but powerful tool for identifying biomolecules involved in angiogenesis. A detailed experimental protocol on the implementation of the assay is described in conjunction with an in-depth review of methods that can be applied to the analysis of the tube formation. In addition, an ImageJ plug-in is presented which allows automatic quantification of tube images reducing analysis times while removing user bias and subjectivity.

  18. Kinking of medical tubes.

    PubMed

    Ingles, David

    2004-05-01

    The phenomenon of kinking in medical tubing remains a problem for some applications, particularly critical ones such as transporting gasses or fluids. Design features are described to prevent its occurrence.

  19. Ear tube insertion

    MedlinePlus

    ... Ear tube surgery - what to ask your doctor Review Date 8/5/2015 Updated by: Sumana Jothi ... Otolaryngology, NCHCS VA, SFVA, San Francisco, CA. Internal review and update on 09/01/2016 by David ...

  20. Ear tube insertion - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100045.htm Ear tube insertion - series—Normal anatomy To use the ... 4 Overview The eardrum (tympanic membrane) separates the ear canal from the middle ear. Review Date 8/ ...

  1. Gastrostomy tube placement - slideshow

    MedlinePlus

    ... presentations/100125.htm Gastrostomy tube placement - series—Normal anatomy To use the sharing features on this page, ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...

  2. Triboelectric sensor for self-powered tracking of object motion inside tubing.

    PubMed

    Su, Yuanjie; Zhu, Guang; Yang, Weiqing; Yang, Jin; Chen, Jun; Jing, Qingshen; Wu, Zhiming; Jiang, Yadong; Wang, Zhong Lin

    2014-04-22

    We report a self-powered, single-electrode-based triboelectric sensor (SE-TES) array for detecting object motion inside of a plastic tube. This innovative, cost-effective, simple-designed SE-TES consists of thin-film-based ring-shaped Cu electrodes and a polytetrafluoroethylene (PTFE) tube. On the basis of the coupling effect between triboelectrification and electrostatic induction, the sensor generates electric output signals in response to mechanical motion of an object (such as a ball) passing through the electrodes. An array of Cu electrodes linearly aligned along the tube enables the detection of location and speed of the moving steel ball inside. The signal-to-noise ratio of this fabricated device reached 5.3 × 10(3). Furthermore, we demonstrated real-time monitoring and mapping of the motion characteristics of the steel ball inside the tube by using a seven-unit array of electrode channels arranged along the tube. Triggered by the output current signal, LED bulbs were utilized as real-time indicators of the position of a rolling ball. In addition, the SE-TES also shows the capability of detecting blockage in a water pipe. This work demonstrates potentially widespread applications of the triboelectric sensor in a self-powered tracking system, blockage detection, flow control, and logistics monitoring.

  3. Clearing obstructed feeding tubes.

    PubMed

    Marcuard, S P; Stegall, K L; Trogdon, S

    1989-01-01

    This is a report of an in vitro study evaluating the ability of six solutions to dissolve clotted enteral feeding, which can cause feeding tube occlusion. The following clotted enteral feeding products were tested: Ensure Plus, Ensure Plus with added protein (Promod 20 g/liter), Osmolite, Enrich, and Pulmocare. Clot dissolution was then tested by adding Adolf's Meat Tenderizer, Viokase, Sprite, Pepsi, Coke, or Mountain Dew. Distilled water served as control. Dissolution score for each mixture was assessed blindly. Best dissolution was observed with Viokase in pH 7.9 solution (p less than 0.01). Similar results were obtained when feeding tube patency was restored in eight in vitro occluded feeding tubes (Dobbhoff, French size 8) by using first Pepsi (two/eight successful) and then Viokase in pH 7.9 (six/six successful). We also report our experience in the first 10 patients with occluded feeding tubes using this Viokase solution injected through a Drum catheter into the feeding tube. In seven patients, this method proved to be successful, and the reasons for failure in three patients include a knotted tube, impacted tablet powder, and a formula clot fo 24 hr duration and 45 cm in length.

  4. Membrane Bioprobe Electrodes

    ERIC Educational Resources Information Center

    Rechnitz, Garry A.

    1975-01-01

    Describes the design of ion selective electrodes coupled with immobilized enzymes which operate either continuously or on drop-sized samples. Cites techniques for urea, L-phenylalanine and amygdalin. Micro size electrodes for use in single cells are discussed. (GH)

  5. Electrode stabilizing materials

    DOEpatents

    Amine, Khalil; Abouimrane, Ali; Moore, Jeffrey S.; Odom, Susan A.

    2015-11-03

    An electrolyte includes a polar aprotic solvent; an alkali metal salt; and an electrode stabilizing compound that is a monomer, which when polymerized forms an electrically conductive polymer. The electrode stabilizing compound is a thiophene, a imidazole, a anilines, a benzene, a azulene, a carbazole, or a thiol. Electrochemical devices may incorporate such electrolytes.

  6. Long term flight electrodes

    NASA Technical Reports Server (NTRS)

    Mosier, B.

    1975-01-01

    The reproducibility, stability, and methods of preparation for the various types and forms of biomedical electrodes are discussed. A critical and selective compilation of information on biological and/or physiological electrodes is presented. A discussion of plant hydrocolloids, clays, hydrophyllic colloids, synthetic waxes, and acrylic polymers is included.

  7. HIGH VOLTAGE ELECTRODES

    DOEpatents

    Murray, J.J.

    1963-04-23

    S>This patent relates to electrode structure for creating an intense direct current electric field which may have a field strength of the order of two to three times that heretofore obtained, with automatic suppression of arcing. The positive electrode is a conventional conductive material such as copper while the negative electrode is made from a special material having a resistivity greater than that of good conductors and less than that of good insulators. When an incipient arc occurs, the moderate resistivity of the negative electrode causes a momentary, localized decrease in the electric field intensity, thus suppressing the flow of electrons and avoiding arcing. Heated glass may be utilized for the negative electrode, since it provides the desired combination of resistivity, capacity, dielectric strength, mechani-cal strength, and thermal stability. (AEC)

  8. Bifunctional catalytic electrode

    NASA Technical Reports Server (NTRS)

    Cisar, Alan (Inventor); Murphy, Oliver J. (Inventor); Clarke, Eric (Inventor)

    2005-01-01

    The present invention relates to an oxygen electrode for a unitized regenerative hydrogen-oxygen fuel cell and the unitized regenerative fuel cell having the oxygen electrode. The oxygen electrode contains components electrocatalytically active for the evolution of oxygen from water and the reduction of oxygen to water, and has a structure that supports the flow of both water and gases between the catalytically active surface and a flow field or electrode chamber for bulk flow of the fluids. The electrode has an electrocatalyst layer and a diffusion backing layer interspersed with hydrophilic and hydrophobic regions. The diffusion backing layer consists of a metal core having gas diffusion structures bonded to the metal core.

  9. Management of chest drainage tubes after lung surgery.

    PubMed

    Satoh, Yukitoshi

    2016-06-01

    Since chest tubes have been routinely used to drain the pleural space, particularly after lung surgery, the management of chest tubes is considered to be essential for the thoracic surgeon. The pleural drainage system requires effective drainage, suction, and water-sealing. Another key point of chest tube management is that a water seal is considered to be superior to suction for most air leaks. Nowadays, the most common pleural drainage device attached to the chest tube is the three-bottle system. An electronic chest drainage system has been developed that is effective in standardizing the postoperative management of chest tubes. More liberal use of digital drainage devices in the postoperative management of the pleural space is warranted. The removal of chest tubes is a common procedure occurring almost daily in hospitals throughout the world. Extraction of the tube is usually done at the end of full inspiration or at the end of full expiration. The tube removal technique is not as important as how it is done and the preparation for the procedure. The management of chest tubes must be based on careful observation, the patient's characteristics, and the operative procedures that had been performed.

  10. Coiled tubing operations and services

    SciTech Connect

    Jaworsky, A.S. II )

    1991-11-01

    Coiled tubing offers many advantages over conventional jointed tubing used for drilling in oil fields, including time savings, pumping flexibility, fluid placement, reduced formation damage and safety. The article gives an overview of coiled tubing history and development. Operating concepts are explained, along with descriptions of the major equipment and components associated with coiled tubing use in the oil field today.

  11. Personal continuous air monitor

    DOEpatents

    Morgan, Ronald G.; Salazar, Samuel A.

    2000-01-01

    A personal continuous air monitor capable of giving immediate warning of the presence of radioactivity has a filter/detector head to be worn in the breathing zone of a user, containing a filter mounted adjacent to radiation detectors, and a preamplifier. The filter/detector head is connected to a belt pack to be worn at the waist or on the back of a user. The belt pack contains a signal processor, batteries, a multichannel analyzer, a logic circuit, and an alarm. An air pump also is provided in the belt pack for pulling air through the filter/detector head by way of an air tube.

  12. Electrodes for sealed secondary batteries

    NASA Technical Reports Server (NTRS)

    Boies, D. B.; Child, F. T.

    1972-01-01

    Self-supporting membrane electrode structures, in which active ingredients and graphite are incorporated in a polymeric matrix, improve performance of electrodes in miniature, sealed, alkaline storage batteries.

  13. Aluminum-based metal-air batteries

    DOEpatents

    Friesen, Cody A.; Martinez, Jose Antonio Bautista

    2016-01-12

    Provided in one embodiment is an electrochemical cell, comprising: (i) a plurality of electrodes, comprising a fuel electrode that comprises aluminum and an air electrode that absorbs gaseous oxygen, the electrodes being operable in a discharge mode wherein the aluminum is oxidized at the fuel electrode and oxygen is reduced at the air electrode, and (ii) an ionically conductive medium, comprising an organic solvent; wherein during non-use of the cell, the organic solvent promotes formation of a protective interface between the aluminum of the fuel electrode and the ionically conductive medium, and wherein at an onset of the discharge mode, at least some of the protective interface is removed from the aluminum to thereafter permit oxidation of the aluminum during the discharge mode.

  14. Design and testing of ultralite fabric reflux tubes

    SciTech Connect

    Pauley, K.A.; Antoniak, Z.I.; King, L.L.; Hollenberg, G.W.

    1993-01-01

    This paper describes the design, fabrication, and testing of Ultralite Fabric Reflux Tubes intended to provide thermal control for a Lunar Colony. The Ultralite Fabric Reflux Tubes, under this phase of development, are constructed of thin-walled copper liners overwrapped with aluminoborosilicate fabric. These devices were constructed and tested in air at the Pacific Northwest Laboratory and subsequently taken to the NASA Johnson Space Center for thermal vacuum experimentation.

  15. Design and testing of Ultralite Fabric Reflux Tubes

    SciTech Connect

    Pauley, K.A.; Antoniak, Z.I.; King, L.L.; Hollenberg, G.W. )

    1993-01-10

    This paper describes the design, fabrication, and testing of Ultralite Tubes intended to provide thermal management for habitat modules in a lunar colony. The Ultralite Fabric Reflux Tubes, under this phase of development, are constructed of thin-walled copper liners overwrapped with aluminoborosilicate fabric. These devices were constructed and tested in air at the Pacific Northwest Laboratory and subsequently taken to the NASA Johnson Space Center for thermal vacuum experimentation.

  16. Effect of external floating electrode for enhancing efficiency of generating an atmospheric pressure inductively coupled microplasma

    NASA Astrophysics Data System (ADS)

    Tukasaki, Katsuki; Kumagai, Shinya; Sasaki, Minoru; Toyota Technological Institute Team

    2015-09-01

    To make a plasma source which can generate a microplasma at low power without using an ignitor (ex. high-voltage power supply), we have used an electrically floating electrode inside a glass tube surrounded by an antenna coil of inductive coupling. Helium gas was fed into the glass tube. When VHF power was supplied to the antenna coil, the floating electrode reached electrically high potential and an atmospheric pressure inductively coupled microplasma was generated. The ignition power depended on the length of the floating electrode further. The longer the length was, the less ignition power was. To make the plasma source compact, the floating electrode was moved outside the glass tube (O.D. 1.5mm, I.D. 1mm) while only a part of floating electrode (Ni wire, 10mm, ϕ 0.3mm) was remained inside the glass tube. Both the cable and Ni wire was magnetically connected to each other through the wall of glass tube. With changing the cable length, ignition power was measured. The ignition power varied with the unit of half wavelength of the VHF. The wavelength resonance effect decreased the ignition power. This study was supported by MEXT program for Forming Strategic Research Infrastructure (S1101028) Japan.

  17. Circle nephrostomy tube revisited

    PubMed Central

    Noureldin, Yasser A.; Diab, Christian; Valenti, David; Andonian, Sero

    2016-01-01

    Introduction: There are few options for patients requiring chronic urinary drainage using nephrostomy tubes. Although circle nephrostomy tube (CNT) was invented in 1954, it is rarely used. Its advantages include longer indwelling time such that it is changed semi-annually when compared with the standard nephrostomy tube (SNT), which is changed monthly. However, there are no studies comparing indwelling times and costs with these two tubes. The aim of the present study was to compare CNT with SNT in terms of frequency of tube changes, reasons for earlier tube changes, and associated costs. Methods: Patients who had CNT inserted between 2009 and 2015 were reviewed. The indications for chronic indwelling nephrostomy tubes were tabulated. The frequency of tube changes was compared between CNT and SNT in the same patients. Furthermore, costs associated with insertion and exchange of CNT and SNT were analyzed. Results: Seven patients with mean age of 71.9 ± 7.6 years (range 43–96) had a total of 36 CNT changes. The mean number of CNT changes was four (range 2–5) at a mean interval of 168.3 ± 15.6 days (range 120–231). All patients had SNT prior to converting to CNT. When compared with the mean interval for SNT changes, the mean interval for CNT changes was significantly longer (44.8 ± 19.4 vs. 168.3 ± 41.3 days; p=0.028). Tube blockage and urinary leakage were the most common reasons for earlier than scheduled CNT changes. In our centre, CNT insertion and exchange cost $1965.48 and $923.96 compared with $1450.43 and $803.81 for SNT, respectively. There was an estimated cost savings of $46 861.10 (range $87 414.30 –$40 553.20) for the whole cohort by switching from SNTs to CNTs. Conclusions: Despite the small sample size as the main limitation, this study confirms that CNTs are associated with significantly fewer changes and lower cost when compared with SNTs for poor-surgical-risk patients requiring chronic NTs.

  18. Development of calcium zirconate-based hydrogen sensors with oxide reference electrodes for molten aluminum

    NASA Astrophysics Data System (ADS)

    Krishnan, Vivek

    Hydrogen is a major cause of gas porosity in aluminum and is frequently removed from the melt prior to casting. The degassing process can be better controlled if the hydrogen content in the melt is known. Thus, gas sensors which can make continuous in situ measurements in molten aluminum are needed. Current online hydrogen sensing systems are complex designs which are prohibitively expensive. Solid electrolyte based potentiometric sensors have been developed as an attractive alternate. These sensors have traditionally used a gas phase as the reference electrode. The present design has a condensed-phase reference electrode to avoid the need for transport of the reference gas into and out of the melt. The use of an oxide rather than a hydride phase reference is expected to considerably lower device cost and improve shelf life and reliability. The sensor element consists of a solid electrolyte tube based on 10 mol% Indoped CaZrO3, which was synthesized using both solid oxide and oxalate co-precipitation techniques. Precursor oxalate powders prepared using polymeric surfactants (PEG) were characterized using SEM, XRD, FTIR and particle size analysis. PEG was found to reduce particle size and also influence the process of perovskite formation. The oxalate co-precipitation technique enabled powder synthesis at reduced processing time and temperature. Closed-one-end tubes were slip cast and densified for use as solid electrolytes. Impedance spectroscopy and D.C. resistance measurements were made at temperatures between 650 and 900°C. Undoped CaZrO3 was found to be a p-type conductor in air. Indoped CaZrO3 acted as a proton conductor in air and argon+H2O, whereas the material was found to be a p-type conductor in pure argon. While bulk conduction was found to be homogenous with activation energies matching those from D.C. measurements, conduction across the grain boundary was found to be heterogeneous. Potentiometric sensors using In-doped CaZrO3 as the electrolyte, and

  19. Electrode for electrochemical cell

    DOEpatents

    Kaun, T.D.; Nelson, P.A.; Miller, W.E.

    1980-05-09

    An electrode structure for a secondary electrochemical cell includes an outer enclosure defining a compartment containing electrochemical active material. The enclosure includes a rigid electrically conductive metal sheet with perforated openings over major side surfaces. The enclosure can be assembled as first and second trays each with a rigid sheet of perforated electrically conductive metal at major side surfaces and normally extending flanges at parametric margins. The trays can be pressed together with moldable active material between the two to form an expandable electrode. A plurality of positive and negative electrodes thus formed are arranged in an alternating array with porous frangible interelectrode separators within the housing of the secondary electrochemical cell.

  20. Electrode for electrochemical cell

    DOEpatents

    Kaun, Thomas D.; Nelson, Paul A.; Miller, William E.

    1981-01-01

    An electrode structure for a secondary electrochemical cell includes an outer enclosure defining a compartment containing electrochemical active material. The enclosure includes a rigid electrically conductive metal sheet with perforated openings over major side surfaces. The enclosure can be assembled as first and second trays each with a rigid sheet of perforated electrically conductive metal at major side surfaces and normally extending flanges at parametric margins. The trays can be pressed together with moldable active material between the two to form an expandable electrode. A plurality of positive and negative electrodes thus formed are arranged in an alternating array with porous frangible interelectrode separators within the housing of the secondary electrochemical cell.

  1. Premixer assembly for mixing air and fuel for combustion

    SciTech Connect

    York, William David; Johnson, Thomas Edward; Keener, Christopher Paul

    2016-12-13

    A premixer assembly for mixing air and fuel for combustion includes a plurality of tubes disposed at a head end of a combustor assembly. Also included is a tube of the plurality of tubes, the tube including an inlet end and an outlet end. Further included is at least one non-circular portion of the tube extending along a length of the tube, the at least one non-circular portion having a non-circular cross-section, and the tube having a substantially constant cross-sectional area along its length

  2. Experimental Investigation of Free-Convection Heat Transfer in Vertical Tube at Large Grashof Numbers

    NASA Technical Reports Server (NTRS)

    Eckert, E R G; Diaguila, A J

    1955-01-01

    Report presents the results of an investigation conducted to study free-convection heat transfer in a stationary vertical tube closed at the bottom. The walls of the tube were heated, and heated air in the tube was continuously replaced by fresh cool air at the top. The tube was designed to provide a gravitational field with Grashof numbers of a magnitude comparable with those generated by the centrifugal field in rotating-blade coolant passages (10(8) to 10(13)). Local heat-transfer coefficients in the turbulent-flow range and the temperature field within the fluid were obtained.

  3. Nitrogen gas propagation in a liquid helium cooled vacuum tube following a sudden vacuum loss

    NASA Astrophysics Data System (ADS)

    Dhuley, R. C.; Van Sciver, S. W.

    2017-02-01

    We present experimental measurements and analysis of propagation of the nitrogen gas that was vented to a high vacuum tube immersed in liquid helium (LHe). The scenario resembles accidental venting of atmospheric air to a SRF beam-line and was investigated to understand how the in-flowing air would propagate in such geometry. The gas front propagation speed in the tube was measured using pressure probes and thermometers installed at regular intervals over the tube length. The experimental data show the front speed to decrease along the vacuum tube. The empirical and analytical models developed to characterize the front deceleration are summarized.

  4. Neural tube defects.

    PubMed

    Greene, Nicholas D E; Copp, Andrew J

    2014-01-01

    Neural tube defects (NTDs), including spina bifida and anencephaly, are severe birth defects of the central nervous system that originate during embryonic development when the neural tube fails to close completely. Human NTDs are multifactorial, with contributions from both genetic and environmental factors. The genetic basis is not yet well understood, but several nongenetic risk factors have been identified as have possibilities for prevention by maternal folic acid supplementation. Mechanisms underlying neural tube closure and NTDs may be informed by experimental models, which have revealed numerous genes whose abnormal function causes NTDs and have provided details of critical cellular and morphological events whose regulation is essential for closure. Such models also provide an opportunity to investigate potential risk factors and to develop novel preventive therapies.

  5. The electrostatic storage tube

    NASA Technical Reports Server (NTRS)

    Rutherford, R. E., Jr.

    1973-01-01

    An electrostatic camera system is discussed which is based on the electrostatic storage tube. The development of the system was begun following a series of experiments which indicated that the device offers signficantly improved performance over currently available devices. The approach used in developing the high performance camera involves: converting the input image to an electron image at low loss, applying a low noise gain process, and storing the resulting charge pattern in a low-loss target. The basic processes and elements of the electrostatic storage tube are illustrated and discussed. Graphs that depict the camera performance characteristics are included.

  6. PRODUCTION OF URANIUM TUBING

    DOEpatents

    Creutz, E.C.

    1958-04-15

    The manufacture of thin-walled uranium tubing by the hot-piercing techique is described. Uranium billets are preheated to a temperature above 780 d C. The heated billet is fed to a station where it is engaged on its external surface by three convex-surfaced rotating rollers which are set at an angle to the axis of the billet to produce a surface friction force in one direction to force the billet over a piercing mandrel. While being formed around the mandrel and before losing the desired shape, the tube thus formed is cooled by a water spray.

  7. Improved capacitive EKG electrode

    NASA Technical Reports Server (NTRS)

    Day, J. L.; Griffith, M. E.; Portnox, W. M.; Stotts, L. J.

    1979-01-01

    Light, compact electrode monitors heart signals through burn ointment and requires no electrolyte paste for coupling to skin. Innovation is useful because of its ability to monitor heart condition of burn victims.

  8. Manufacturing SP-100 rhenium tubes

    NASA Astrophysics Data System (ADS)

    Sayre, Edwin D.; Ruffo, Thomas J.

    1992-01-01

    A process for producing high quality, thin walled, wrought, rhenium tubing was successfully developed and qualified in the SP-100 fuel fabrication program. Rhenium was selected for the fuel-cladding barrier versus tungsten because of the cold workability and nuclear characteristics of rhenium. Several tube fabricating processes including swaging, drawing, and extruding sintered tube shells and chemical vapor deposition were evaluated before a drawn tube made by forming and electron beam welding rhenium strip was selected as the most cost effective. The process for making the rhenium tubes is discussed in general and the tube, room temperature, tensile properties are compared favorably with the properties reported in the literature.

  9. Conducting polymer electrodes for electroencephalography.

    PubMed

    Leleux, Pierre; Badier, Jean-Michel; Rivnay, Jonathan; Bénar, Christian; Hervé, Thierry; Chauvel, Patrick; Malliaras, George G

    2014-04-01

    Conducting polymer electrodes are developed on a flexible substrate for electroencephalography applications. These electrodes yield higher quality recordings than dry electrodes made from metal. Their performance is equivalent to commercial gel-assisted electrodes, paving the way for non-invasive, long-term monitoring of the human brain.

  10. The development of an improved streak tube for fusion diagnostics

    NASA Astrophysics Data System (ADS)

    Howorth, J. R.; Milnes, J. S.; Fisher, Y.; Jadwin, A.; Boni, R.; Jaanimagi, P. A.

    2016-11-01

    The fusion diagnostic community, including the National Ignition Facility, the Laboratory for Laser Energetics, Megajoule in France, and others require optical recording instruments with precise time resolution covering a dynamic range of many orders of magnitude. In 2012, LLE, Photek, and Sydor Instruments embarked on the re-design of an improved streak tube for fusion diagnostics. As a baseline we started with the Photek ST-Y streak tube which is a member of the RCA design dating back to 1957, because the tube body can accommodate a 35 mm long photocathode, and consequently more fibre coupled diagnostic channels than smaller designs. Electron optical modelling was carried out by both Paul Jaanimagi in the US and by Photek with different software packages in a parallel exercise. Our goal was to address some of the short-comings of this tube, the initial approach being to increase the field between the photocathode and extractor electrode from 700 to 1300 V/mm to reduce space charge effects and to improve time resolution. Many changes and modifications were made: the time resolution was improved to 5 ps, the usable cathode length was increased from 20 mm to 32 mm under high extraction field operation, and the off-axis spatial resolution was substantially improved compared to other tubes of this format. Several tubes have been built and tested in Sydor ROSS-5800 streak cameras.

  11. Methods for batch fabrication of cold cathode vacuum switch tubes

    DOEpatents

    Walker, Charles A.; Trowbridge, Frank R.

    2011-05-10

    Methods are disclosed for batch fabrication of vacuum switch tubes that reduce manufacturing costs and improve tube to tube uniformity. The disclosed methods comprise creating a stacked assembly of layers containing a plurality of adjacently spaced switch tube sub-assemblies aligned and registered through common layers. The layers include trigger electrode layer, cathode layer including a metallic support/contact with graphite cathode inserts, trigger probe sub-assembly layer, ceramic (e.g. tube body) insulator layer, and metallic anode sub-assembly layer. Braze alloy layers are incorporated into the stacked assembly of layers, and can include active metal braze alloys or direct braze alloys, to eliminate costs associated with traditional metallization of the ceramic insulator layers. The entire stacked assembly is then heated to braze/join/bond the stack-up into a cohesive body, after which individual switch tubes are singulated by methods such as sawing. The inventive methods provide for simultaneously fabricating a plurality of devices as opposed to traditional methods that rely on skilled craftsman to essentially hand build individual devices.

  12. Heat transfer and hydrodynamics analysis of a novel dimpled tube

    SciTech Connect

    Wang, Yu.; He, Ya-Ling; Lei, Yong-Gang; Zhang, Jie

    2010-11-15

    In the present investigation, heat transfer and hydrodynamics analysis of a new enhanced heat transfer tube with ellipsoidal dimples was carried out. The dimples are disposed to form a certain specified angle between the major axis of the ellipsoid and flow direction, and the direction of the major axis of each adjacent ellipsoidal dimple in the same cross-section is alternated. Experimental tests were carried out with heating water on the shell side with a constant flow rate, and cold air in the tube side with flow rates range from 1 to 55 m{sup 3}/h. The temperatures and pressures for the inlet and outlet of both sides were measured. The heat transfer and pressure drop of the new dimpled tube were investigated and compared with the results of a dimpled tube with spherical dimples and a conventional smooth tube. The computed results indicated that the Nusselt number for ellipsoidal dimpled tube and spherical dimpled tube are 38.6-175.1% and 34.1-158% higher than that for the smooth tube respectively. The friction factors of dimpled tube increase by 26.9-75% and 32.9-92% for ellipsoidal and spherical dimples compared with the smooth tube respectively. It was perceived that ellipsoidal dimple roughness accelerates transition to critical Reynolds numbers down to less than 1000. By integrated performance evaluation of (Nu{sub a}/Nu{sub s})/(f{sub a}/f{sub s}), a maximum of about 87% heat transfer enhancement with the same friction penalty could be achieved by optimize the dimpled tube design. (author)

  13. Heat-shrink plastic tubing seals joints in glass tubing

    NASA Technical Reports Server (NTRS)

    Del Duca, B.; Downey, A.

    1968-01-01

    Small units of standard glass apparatus held together by short lengths of transparent heat-shrinkable polyolefin tubing. The tubing is shrunk over glass O-ring type connectors having O-rings but no lubricant.

  14. Flux Tube Model

    NASA Astrophysics Data System (ADS)

    Steiner, O.

    2011-05-01

    This Fortran code computes magnetohydrostatic flux tubes and sheets according to the method of Steiner, Pneuman, & Stenflo (1986) A&A 170, 126-137. The code has many parameters contained in one input file that are easily modified. Extensive documentation is provided in README files.

  15. Snorkeling and Jones tubes

    PubMed Central

    Lam, Lewis Y. W.; Weatherhead, Robert G.

    2015-01-01

    Summary We report a case of tympanic membrane rupture during snorkeling in a 17-year-old young man who had previously undergone bilateral Jones tubes placed for epiphora. To our knowledge, this phenomenon has not been previously reported. PMID:27330470

  16. Tube Feeding Transition Plateaus

    ERIC Educational Resources Information Center

    Klein, Marsha Dunn

    2007-01-01

    The journey children make from tube feeding to oral feeding is personal for each child and family. There is a sequence of predictable plateaus that children climb as they move toward orally eating. By better understanding this sequence, parents and children can maximize the development, learning, enjoyment and confidence at each plateau. The…

  17. Misdirected Minitracheostomy Tube

    PubMed Central

    Singh, Ajmer; Nanda, Chinmaya; Mehta, Yatin

    2017-01-01

    We report a patient who after an uneventful coronary artery bypass graft surgery and left ventricular aneurysmorrhaphy developed intracerebral hemorrhage and subsequently required minitracheostomy. Chest X-ray showed misdirected minitracheostomy tube facing upward toward the laryngeal opening which was repositioned using bronchoscope. PMID:28074805

  18. Misdirected minitracheostomy tube.

    PubMed

    Singh, Ajmer; Nanda, Chinmaya; Mehta, Yatin

    2017-01-01

    We report a patient who after an uneventful coronary artery bypass graft surgery and left ventricular aneurysmorrhaphy developed intracerebral hemorrhage and subsequently required minitracheostomy. Chest X-ray showed misdirected minitracheostomy tube facing upward toward the laryngeal opening which was repositioned using bronchoscope.

  19. Investigation of Pitot tubes

    NASA Technical Reports Server (NTRS)

    Herschel, W H; Buckingham, E

    1917-01-01

    Report describes the principles of operation and characteristics of some of the instruments which have been devised or used to measure both low and high speeds of aeroplanes. Since the pitot tube is the instrument which has been most commonly used in the United States and Great Britain as a speedometer for aeroplanes, it is treated first and somewhat more fully than the others.

  20. Downhole pulse tube refrigerators

    SciTech Connect

    Swift, G.; Gardner, D.

    1997-12-01

    This report summarizes a preliminary design study to explore the plausibility of using pulse tube refrigeration to cool instruments in a hot down-hole environment. The original motivation was to maintain Dave Reagor`s high-temperature superconducting electronics at 75 K, but the study has evolved to include three target design criteria: cooling at 30 C in a 300 C environment, cooling at 75 K in a 50 C environment, cooling at both 75 K and 30 C in a 250 C environment. These specific temperatures were chosen arbitrarily, as representative of what is possible. The primary goals are low cost, reliability, and small package diameter. Pulse-tube refrigeration is a rapidly growing sub-field of cryogenic refrigeration. The pulse tube refrigerator has recently become the simplest, cheapest, most rugged and reliable low-power cryocooler. The authors expect this technology will be applicable downhole because of the ratio of hot to cold temperatures (in absolute units, such as Kelvin) of interest in deep drilling is comparable to the ratios routinely achieved with cryogenic pulse-tube refrigerators.

  1. Capacitive de-ionization electrode

    DOEpatents

    Daily, III, William D.

    2013-03-19

    An electrode "cell" for use in a capacitive deionization (CDI) reactor consists of the electrode support structure, a non-reactive conductive material, the electrode accompaniment or substrate and a flow through screen/separator. These "layers" are repeated and the electrodes are sealed together with gaskets between two end plates to create stacked sets of alternating anode and cathode electrodes in the CDI reactor.

  2. Fuel electrode containing pre-sintered nickel/zirconia for a solid oxide fuel cell

    DOEpatents

    Ruka, Roswell J.; Vora, Shailesh D.

    2001-01-01

    A fuel cell structure (2) is provided, having a pre-sintered nickel-zirconia fuel electrode (6) and an air electrode (4), with a ceramic electrolyte (5) disposed between the electrodes, where the pre-sintered fuel electrode (6) contains particles selected from the group consisting of nickel oxide, cobalt and cerium dioxide particles and mixtures thereof, and titanium dioxide particles, within a matrix of yttria-stabilized zirconia and spaced-apart filamentary nickel strings having a chain structure, and where the fuel electrode can be sintered to provide an active solid oxide fuel cell.

  3. Rubens Flame-Tube Demonstration.

    ERIC Educational Resources Information Center

    Ficken, George W.; Stephenson, Francis C.

    1979-01-01

    Investigates and explains the phenomenon associated with Rubens flame-tube demonstration, specifically the persistance of flames at regular intervals along the tube for few minutes after the gas is turned off. (GA)

  4. Tubing For Sampling Hydrazine Vapor

    NASA Technical Reports Server (NTRS)

    Travis, Josh; Taffe, Patricia S.; Rose-Pehrsson, Susan L.; Wyatt, Jeffrey R.

    1993-01-01

    Report evaluates flexible tubing used for transporting such hypergolic vapors as those of hydrazines for quantitative analysis. Describes experiments in which variety of tubing materials, chosen for their known compatibility with hydrazine, flexibility, and resistance to heat.

  5. Nickel gradient electrode

    SciTech Connect

    Zimmerman, A.H.

    1988-03-31

    This invention relates generally to rechargeable batteries, and, in particular, relates to batteries that use nickel electrodes. It provides an improved nickel electrode with a selected gradient of additive materials. The concentration of additives in the impregnating solution are controlled during impregnation such that an additive gradient is generated. In the situation where the highest ionic conductivity is needed at the current collector boundary with the active material, the electrochemical impregnating solution is initially high in additive, and at the end of impregnation has been adjusted to significantly lower additive concentration. For chemical impregnation, the electrodes are similarly dipped in solutions that are initially high in additive. This invention is suitable for conventional additives such as cobalt, cadmium, barium, manganese, and zinc. It is therefore one objective of the invention to provide an improved nickel electrode of a battery cell with an additive in the active material to increase the life of the battery cell. Another objective is to provide for an improved nickel electrode having a greater concentration of additive near the current collector of nickel.

  6. Weld electrode cooling study

    NASA Astrophysics Data System (ADS)

    Masters, Robert C.; Simon, Daniel L.

    1999-03-01

    The U.S. auto/truck industry has been mandated by the Federal government to continuously improve their fleet average gas mileage, measured in miles per gallon. Several techniques are typically used to meet these mandates, one of which is to reduce the overall mass of cars and trucks. To help accomplish this goal, lighter weight sheet metal parts, with smaller weld flanges, have been designed and fabricated. This paper will examine the cooling characteristics of various water cooled weld electrodes and shanks used in resistance spot welding applications. The smaller weld flanges utilized in modern vehicle sheet metal fabrications have increased industry's interest in using one size of weld electrode (1/2 inch diameter) for certain spot welding operations. The welding community wants more data about the cooling characteristics of these 1/2 inch weld electrodes. To hep define the cooling characteristics, an infrared radiometer thermal vision system (TVS) was used to capture images (thermograms) of the heating and cooling cycles of several size combinations of weld electrodes under typical production conditions. Tests results will show why the open ended shanks are more suitable for cooling the weld electrode assembly then closed ended shanks.

  7. Collapse pressure of coiled tubing

    SciTech Connect

    Yang, Y.S.

    1996-09-01

    The collapse pressure is a measure of an external force required to collapse a tube in the absence of internal pressure. It is defined as the minimum pressure required to yield the tube in the absence of internal pressure. Coiled tubing is sometimes used in high-pressure wells. If the external pressure becomes too high, the coiled tubing will collapse. This could not only lead to serious well-control problems, but may result in extensive fishing operations. A reliable safety criterion of collapse pressure for the coiled tubing is needed by the coiled tubing operators. Theoretical models of collapse pressure are well developed for perfectly round coiled tubing but not for oval coiled tubing. Coiled tubing is initially manufactured with nearly perfect roundness, sometimes having a small ovality (typically {le} 0.5%). Perfectly round CT becomes oval owing to the plastic mechanical deformation of the coiled tubing as it spooled on and off the reel and over the gooseneck. As the cycling continues, the ovality usually increases. This ovality significantly decreases the collapse failure pressure as compared to perfectly round tubing. In this paper, an analytical model of collapse pressure for oval tubing under axial tension or compression is developed based on elastic instability theory and the von Mises criterion. The theoretical model shows satisfactory agreement with experimental data.

  8. Enteral Tube Feeding and Pneumonia

    ERIC Educational Resources Information Center

    Gray, David Sheridan; Kimmel, David

    2006-01-01

    To determine the effects of enteral tube feeding on the incidence of pneumonia, we performed a retrospective review of all clients at our institution who had gastrostomy or jejunostomy tubes placed over a 10-year period. Ninety-three subjects had a history of pneumonia before feeding tube insertion. Eighty had gastrostomy and 13, jejunostomy…

  9. Air breathing direct methanol fuel cell

    DOEpatents

    Ren, Xiaoming

    2002-01-01

    An air breathing direct methanol fuel cell is provided with a membrane electrode assembly, a conductive anode assembly that is permeable to air and directly open to atmospheric air, and a conductive cathode assembly that is permeable to methanol and directly contacting a liquid methanol source.

  10. Multistage Pulse Tube Refrigeration Characterization of the Northrop Grumman High Capacity Cooler - An Update

    DTIC Science & Technology

    2008-01-01

    Stirling and not a pulse tube cryocooler . While this technology is significantly different from the HCC (dual pulse tube), both coolers have two stages...International Cryocooler Conference, pp. 219-224, 2003. 2. Roberts, T. et al, “Multistage Stirling Cycle Refrigeration Performance Mapping of the Ball... cryocooler by the Air Force Research Laboratory. This cooler?s design uses two pulse tube cold ends in parallel. The nominal 85 K cold end is thermally

  11. Porous electrode preparation method

    DOEpatents

    Arons, R.M.; Dusek, J.T.

    1983-10-18

    A porous sintered plaque is provided with a bimodal porosity that is especially well suited for use as an electrode within a molten carbonate fuel cell. The coarse porosity is sufficient for admitting gases into contact with the reaction surfaces while the fine porosity is wetted with and retains molten electrolyte on the reaction sites. The electrode structure is prepared by providing a very fine powder of such as nickel oxide and blending the powder with a suitable decomposable binder to form a solid mass. The mass is comminuted into agglomerate size particles substantially larger than the fine oxide particles and formed into a cohesive compact for subsequent sintering. Sintering is carried out at sufficient conditions to bind the agglomerates together into a porous structure having both coarse and fine porosity. Where lithiated nickel oxide cathodes are prepared, the sintering conditions can be moderate enough to retain substantial quantities of lithium within the electrode for adequate conductivity. 2 figs.

  12. Composite carbon foam electrode

    DOEpatents

    Mayer, S.T.; Pekala, R.W.; Kaschmitter, J.L.

    1997-05-06

    Carbon aerogels used as a binder for granulated materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy. 1 fig.

  13. Composite carbon foam electrode

    DOEpatents

    Mayer, Steven T.; Pekala, Richard W.; Kaschmitter, James L.

    1997-01-01

    Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivty and power to system energy.

  14. Fuel cell electrode

    SciTech Connect

    Struthers, R. C.

    1985-03-05

    A flat, laminated fuel cell gas electrode arranged between and separating gas and liquid mediums in a fuel cell. The electrode includes a flat, perforated sheet metal support and electric conductor part with a rear surface disposed toward the gas medium, a flat, hydrophobic gas permeable membrane with a rear surface in contact with a front surface of said part, a flat liquid and gas permeable metallic current collector with a rear surface spaced from a front surface of said membrane and with a front surface disposed toward the liquid medium, a catalytic barrier structure of bonded together particulate catalytic material and metal conductor filaments by and in electric conducting contact with the collector and having a rear surface in contact with the front surface of the membrane and a plurality of spaced apart electric conducting fasteners engaged with and between said part and collector securing the parts of the electrode in assembled relationship and electrically connecting the current collector with said part.

  15. Liquid-permeable electrode

    DOEpatents

    Folser, George R.

    1980-01-01

    Electrodes for use in an electrolytic cell, which are liquid-permeable and have low electrical resistance and high internal surface area are provided of a rigid, porous, carbonaceous matrix having activated carbon uniformly embedded throughout. The activated carbon may be catalyzed with platinum for improved electron transfer between electrode and electrolyte. Activated carbon is mixed with a powdered thermosetting phenolic resin and compacted to the desired shape in a heated mold to melt the resin and form the green electrode. The compact is then heated to a pyrolyzing temperature to carbonize and volatilize the resin, forming a rigid, porous structure. The permeable structure and high internal surface area are useful in electrolytic cells where it is necessary to continuously remove the products of the electrochemical reaction.

  16. Chest Tube Thoracostomy

    MedlinePlus

    ... that is done to drain fluid, blood, or air from the space around the lungs. This procedure may be done ... needed include: ■ ■ Collapsed lung (pneumothorax)— This occurs when air has built up in the area around the lungs (the pleural space) from a leak in the lung. This leak ...

  17. Rapid and selective brain cooling method using vortex tube: A feasibility study.

    PubMed

    Bakhsheshi, Mohammad Fazel; Keenliside, Lynn; Lee, Ting-Yim

    2016-05-01

    Vortex tubes are simple mechanical devices to produce cold air from a stream of compressed air without any moving parts. The primary focus of the current study is to investigate the feasibility and efficiency of nasopharyngeal brain cooling method using a vortex tube. Experiments were conducted on 5 juvenile pigs. Nasopharygeal brain cooling was achieved by directing cooled air via a catheter in each nostril into the nasal cavities. A vortex tube was used to generate cold air using various sources of compressed air: (I) hospital medical air outlet (n = 1); (II) medical air cylinders (n = 3); and (III) scuba (diving) cylinders (n = 1). By using compressed air from a hospital medical air outlet at fixed inlet pressure of 50 PSI, maximum brain-rectal temperature gradient of -2°C was reached about 45-60 minutes by setting the flow rate of 25 L/min and temperature of -7°C at the cold air outlet. Similarly, by using medical air cylinders at fill-pressure of 2265 PSI and down regulate the inlet pressure to the vortex tube to 50 PSI, brain temperature could be reduced more rapidly by blowing -22°C ± 2°C air at a flow rate of 50 L/min; brain-body temperature gradient of -8°C was obtained about 30 minutes. Furthermore, we examined scuba cylinders as a portable source of compressed gas supply to the vortex tube. Likewise, by setting up the vortex tube to have an inlet pressure of 25 PSI and 50 L/min and -3°C at the cold air outlet, brain temperature decreased 4.5°C within 10-20 min.

  18. YouTube Physics

    NASA Astrophysics Data System (ADS)

    Riendeau, Diane

    2012-09-01

    To date, this column has presented videos to show in class, Don Mathieson from Tulsa Community College suggested that YouTube could be used in another fashion. In Don's experience, his students are not always prepared for the mathematic rigor of his course. Even at the high school level, math can be a barrier for physics students. Walid Shihabi, a colleague of Don's, decided to compile a list of YouTube videos that his students could watch to relearn basic mathematics. I thought this sounded like a fantastic idea and a great service to the students. Walid graciously agreed to share his list and I have reproduced a large portion of it below.

  19. Tube coupling device

    NASA Technical Reports Server (NTRS)

    Myers, William N. (Inventor); Hein, Leopold A. (Inventor)

    1987-01-01

    A first annular ring of a tube coupling device has a keyed opening sized to fit around the nut region of a male coupling, and a second annular ring has a keyed opening sized to fit around the nut of a female coupling. Each ring has mating ratchet teeth and these rings are biased together, thereby engaging these teeth and preventing rotation of these rings. This in turn prevents the rotation of the male nut region with respect to the female nut. For tube-to-bulkhead locking, one facet of one ring is notched, and a pin is pressed into an opening in the bulkhead. This pin is sized to fit within one of the notches in the ring, thereby preventing rotation of this ring with respect to the bulkhead.

  20. Induction plasma tube

    DOEpatents

    Hull, D.E.

    1982-07-02

    An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.

  1. Induction plasma tube

    DOEpatents

    Hull, Donald E.

    1984-01-01

    An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.

  2. Joined concentric tubes

    DOEpatents

    DeJonghe, Lutgard; Jacobson, Craig; Tucker, Michael; Visco, Steven

    2013-01-01

    Tubular objects having two or more concentric layers that have different properties are joined to one another during their manufacture primarily by compressive and friction forces generated by shrinkage during sintering and possibly mechanical interlocking. It is not necessary for the concentric tubes to display adhesive-, chemical- or sinter-bonding to each other in order to achieve a strong bond. This facilitates joining of dissimilar materials, such as ceramics and metals.

  3. Ceramic component for electrodes

    DOEpatents

    Marchant, David D.

    1979-01-01

    A ceramic component suitable for preparing MHD generator electrodes consists of HfO.sub.2 and sufficient Tb.sub.4 O.sub.7 to stabilize at least 60 volume percent of the HfO.sub.2 into the cubic structure. The ceramic component may also contain a small amount of PrO.sub.2, Yb.sub.2 O.sub.3 or a mixture of both to improve stability and electronic conductivity of the electrode. The component is highly resistant to corrosion by molten potassium seed and molten coal slag in the MHD fluid and exhibits both ionic and electronic conductivity.

  4. Sandwich-type electrode

    DOEpatents

    Lu, Wen-Tong P.; Garcia, Earl R.

    1983-01-01

    Disclosed is an improvement on a method of making an electrode wherein a suspension in a liquid is prepared of a powdered catalyst containing a noble metal, carbon powder and a binder, and the suspension is poured over a carbon substrate dried, compressed and sintered to form a solid catalyst layer bonded to the carbon substrate. The improvement is placing a carbon paper on the catalyst layer prior to compressing. The improved electrode can be used as either a cathode or an anode in a sulfur dioxide depolarized electrolyzer in a process for producing hydrogen from water.

  5. Aluminum reference electrode

    DOEpatents

    Sadoway, D.R.

    1988-08-16

    A stable reference electrode is described for use in monitoring and controlling the process of electrolytic reduction of a metal. In the case of Hall cell reduction of aluminum, the reference electrode comprises a pool of molten aluminum and a solution of molten cryolite, Na[sub 3]AlF[sub 6], wherein the electrical connection to the molten aluminum does not contact the highly corrosive molten salt solution. This is accomplished by altering the density of either the aluminum (decreasing the density) or the electrolyte (increasing the density) so that the aluminum floats on top of the molten salt solution. 1 fig.

  6. Aluminum reference electrode

    DOEpatents

    Sadoway, Donald R.

    1988-01-01

    A stable reference electrode for use in monitoring and controlling the process of electrolytic reduction of a metal. In the case of Hall cell reduction of aluminum, the reference electrode comprises a pool of molten aluminum and a solution of molten cryolite, Na.sub.3 AlF.sub.6, wherein the electrical connection to the molten aluminum does not contact the highly corrosive molten salt solution. This is accomplished by altering the density of either the aluminum (decreasing the density) or the electrolyte (increasing the density) so that the aluminum floats on top of the molten salt solution.

  7. Apparatus Splits Glass Tubes Longitudinally

    NASA Technical Reports Server (NTRS)

    Shaw, Ernest; Manahan, Robert O'neil

    1993-01-01

    Tubes split into half cylinders by hot-wire/thermal-shock method. Tube to be cut placed on notched jig in apparatus. Nichrome wire stretched between arms of pivoted carriage and oriented parallel to notch. Wire heated by electrical current while resting on tube. After heating for about 1 minute for each millimeter of thickness of glass, tube quenched in water and split by resulting thermal shock. Apparatus used to split tubes in sizes ranging from 3/8 in. in diameter by 1 in. long to 1 1/2 in. in diameter by 4 in. long.

  8. Tube bundle system

    PubMed Central

    Marchewka, W.; Mohamed, K.; Addis, J.; Karnack, F.

    2015-01-01

    A tube bundle system (TBS) is a mechanical system for continuously drawing gas samples through tubes from multiple monitoring points located in an underground coal mine. The gas samples are drawn via vacuum pump to the surface and are typically analyzed for oxygen, methane, carbon dioxide and carbon monoxide. Results of the gas analyses are displayed and recorded for further analysis. Trends in the composition of the mine atmosphere, such as increasing methane or carbon monoxide concentration, can be detected early, permitting rapid intervention that prevents problems, such as a potentially explosive atmosphere behind seals, fire or spontaneous combustion. TBS is a well-developed technology and has been used in coal mines around the world for more than 50 years. Most longwall coal mines in Australia deploy a TBS, usually with 30 to 40 monitoring points as part of their atmospheric monitoring. The primary uses of a TBS are detecting spontaneous combustion and maintaining sealed areas inert. The TBS might also provide mine atmosphere gas composition data after a catastrophe occurs in an underground mine, if the sampling tubes are not damaged. TBSs are not an alternative to statutory gas and ventilation airflow monitoring by electronic sensors or people; rather, they are an option to consider in an overall mine atmosphere monitoring strategy. This paper describes the hardware, software and operation of a TBS and presents one example of typical data from a longwall coal mine PMID:26306052

  9. Traveling-Wave Tubes

    NASA Technical Reports Server (NTRS)

    Kory, Carol L.

    1998-01-01

    The traveling-wave tube (TWT) is a vacuum device invented in the early 1940's used for amplification at microwave frequencies. Amplification is attained by surrendering kinetic energy from an electron beam to a radio frequency (RF) electromagnetic wave. The demand for vacuum devices has been decreased largely by the advent of solid-state devices. However, although solid state devices have replaced vacuum devices in many areas, there are still many applications such as radar, electronic countermeasures and satellite communications, that require operating characteristics such as high power (Watts to Megawatts), high frequency (below 1 GHz to over 100 GHz) and large bandwidth that only vacuum devices can provide. Vacuum devices are also deemed irreplaceable in the music industry where musicians treasure their tube-based amplifiers claiming that the solid-state and digital counterparts could never provide the same "warmth" (3). The term traveling-wave tube includes both fast-wave and slow-wave devices. This article will concentrate on slow-wave devices as the vast majority of TWTs in operation fall into this category.

  10. Concentric tube support assembly

    DOEpatents

    Rubio, Mark F.; Glessner, John C.

    2012-09-04

    An assembly (45) includes a plurality of separate pie-shaped segments (72) forming a disk (70) around a central region (48) for retaining a plurality of tubes (46) in a concentrically spaced apart configuration. Each segment includes a support member (94) radially extending along an upstream face (96) of the segment and a plurality of annularly curved support arms (98) transversely attached to the support member and radially spaced apart from one another away from the central region for receiving respective upstream end portions of the tubes in arc-shaped spaces (100) between the arms. Each segment also includes a radial passageway (102) formed in the support member for receiving a fluid segment portion (106) and a plurality of annular passageways (104) formed in the support arms for receiving respective arm portions (108) of the fluid segment portion from the radial passageway and for conducting the respective arm portions into corresponding annular spaces (47) formed between the tubes retained by the disk.

  11. TUBE SHEARING VALVE

    DOEpatents

    Wilner, L.B.

    1960-05-24

    Explosive operated valves can be used to join two or more containers in fluid flow relationship, one such container being a sealed reservoir. The valve is most simply disposed by mounting it on the reservoir so thst a tube extends from the interior of the reservoir through the valve body, terminating at the bottom of the bore in a closed end; other containers may be similarly connected or may be open connected, as desired. The piston of the valve has a cutting edge at its lower end which shears off the closed tube ends and a recess above the cutting edge to provide a flow channel. Intermixing of the fluid being transferred with the explosion gases is prevented by a copper ring at the top of the piston which is force fitted into the bore at the beginning of the stroke. Although designed to avoid backing up of the piston at pressures up to 10,000 psi in the transferred fluid, proper operation is independent of piston position, once the tube ends were sheared.

  12. Dual porosity gas evolving electrode

    DOEpatents

    Townsend, Carl W.

    1994-01-01

    A dual porosity electrode for use in thermoelectrochemical systems where simultaneous transport of gas and liquid into and/or out of the electrode is required. The electrode includes catalytic electrode particles having diameters ranging from about 25 to 100 angstroms. The catalytic electrode particles are anchored to a support network in clusters which have internal pores ranging in size from 25 to 100 angstroms. The pores between the clusters range in size from between about 1 to 20 microns. A method for making the dual porosity electrodes is also disclosed.

  13. Dual porosity gas evolving electrode

    DOEpatents

    Townsend, C.W.

    1994-11-15

    A dual porosity electrode is described for use in thermoelectrochemical systems where simultaneous transport of gas and liquid into and/or out of the electrode is required. The electrode includes catalytic electrode particles having diameters ranging from about 25 to 100 angstroms. The catalytic electrode particles are anchored to a support network in clusters which have internal pores ranging in size from 25 to 100 angstroms. The pores between the clusters range in size from between about 1 to 20 microns. A method for making the dual porosity electrodes is also disclosed.

  14. Electrical properties of textile electrodes.

    PubMed

    Rattfalt, Linda; Chedid, Michel; Hult, Peter; Lindén, Maria; Ask, Per

    2007-01-01

    In this study we aim to explain the behavior of textile electrodes due to their construction techniques. Three textile electrodes were tested for electrode impedance and polarization potentials. The multifilament yarn (A) is favorable for its low thread resistance. Although, when knitted into electrodes, the staple fiber yarn (B) showed a comparable and satisfiable electrode impedance. The multifilament yarn had however a lower polarization potential drift then the other specimens. The monofilament yarn (C) had high electrode impedance and varying mean polarization potentials due to its conductive material and small contact area with the skin.

  15. Solid-Sorbent Air Sampler

    NASA Technical Reports Server (NTRS)

    Galen, T. J.

    1986-01-01

    Portable unit takes eight 24-hour samples. Volatile organic compounds in air collected for analysis by portable, self-contained sampling apparatus. Sampled air drawn through sorbent material, commercial porous polymer of 2, 3-diphenyl-p-phenylene oxide. High-boiling-point organic compounds adsorbed onto polymer, while low-boiling-point organics pass through and returned to atmosphere. Sampler includes eight sample tubes filled with polymeric sorbent. Organic compounds in atmosphere absorbed when air pumped through sorbent. Designed for checking air in spacecraft, sampler adaptable to other applications as leak detection, gas-mixture analysis, and ambient-air monitoring.

  16. Experimental correlation for flooding vapor velocity in a fluted tube with a twisted insert

    SciTech Connect

    Kang, Y.T.; Stout, R.; Christensen, R.N.

    1996-12-31

    This paper develops a flooding correlation from experiments in a fluted tube with a twisted insert for application to absorption heat pump systems. Fluted tubes have been used to enhance both heat and mass transfer during absorption and desorption processes. In the present tests, a plastic twisted tape was inserted to increase the absorption rate in counter current absorption. The effects of the twisted insert and the angle of inclination on the flooding were examined. Water and Ethyl alcohol solution flows downward in the fluted tube while air flows counter current in an upward direction. The flooding mechanism in a fluted tube with a twisted insert was analyzed by visual observation, and experimental correlations for the flooding for both vertical and nearly horizontal positions were developed. The experimental data from this paper were compared with those for smooth tubes from the literature. The results show that the flooding initiated form the bottom for the vertical tube, and from the top of the tube for the nearly horizontal tube. The fluctuation of the pressure drop for the vertical tube was much stronger than that for the horizontal tube. The effect of the position of the insert was not significant for the nearly horizontal tube while it was somewhat significant for the vertical tube. The superficial flooding vapor velocity for the nearly horizontal position is lower than that for the vertical position for a given liquid mass flow rate.

  17. Reliability of steam generator tubing

    SciTech Connect

    Kadokami, E.

    1997-02-01

    The author presents results on studies made of the reliability of steam generator (SG) tubing. The basis for this work is that in Japan the issue of defects in SG tubing is addressed by the approach that any detected defect should be repaired, either by plugging the tube or sleeving it. However, this leaves open the issue that there is a detection limit in practice, and what is the effect of nondetectable cracks on the performance of tubing. These studies were commissioned to look at the safety issues involved in degraded SG tubing. The program has looked at a number of different issues. First was an assessment of the penetration and opening behavior of tube flaws due to internal pressure in the tubing. They have studied: penetration behavior of the tube flaws; primary water leakage from through-wall flaws; opening behavior of through-wall flaws. In addition they have looked at the question of the reliability of tubing with flaws during normal plant operation. Also there have been studies done on the consequences of tube rupture accidents on the integrity of neighboring tubes.

  18. Virtual electrodes for high-density electrode arrays

    DOEpatents

    Cela, Carlos J.; Lazzi, Gianluca

    2015-10-13

    The present embodiments are directed to implantable electrode arrays having virtual electrodes. The virtual electrodes may improve the resolution of the implantable electrode array without the burden of corresponding complexity of electronic circuitry and wiring. In a particular embodiment, a virtual electrode may include one or more passive elements to help steer current to a specific location between the active electrodes. For example, a passive element may be a metalized layer on a substrate that is adjacent to, but not directly connected to an active electrode. In certain embodiments, an active electrode may be directly coupled to a power source via a conductive connection. Beneficially, the passive elements may help to increase the overall resolution of the implantable array by providing additional stimulation points without requiring additional wiring or driver circuitry for the passive elements.

  19. Electrically recharged battery employing a packed/spouted bed metal particle electrode

    SciTech Connect

    Siu, S.C.; Evans, J.W.; Salas-Morales, J.

    1995-08-15

    A secondary metal air cell, employing a spouted/packed metal particle bed and an air electrode, is described. More specifically a zinc air cell well suited for use in electric vehicles which is capable of being either electrically or hydraulically recharged. 5 figs.

  20. High performance methanol-oxygen fuel cell with hollow fiber electrode

    NASA Technical Reports Server (NTRS)

    Lawson, Daniel D. (Inventor); Ingham, John D. (Inventor)

    1983-01-01

    A methanol/air-oxygen fuel cell including an electrode formed by open-ended ion-exchange hollow fibers having a layer of catalyst deposited on the inner surface thereof and a first current collector in contact with the catalyst layer. A second current collector external of said fibers is provided which is immersed along with the hollow fiber electrode in an aqueous electrolyte body. Upon passage of air or oxygen through the hollow fiber electrode and introduction of methanol into the aqueous electrolyte, a steady current output is obtained. Two embodiments of the fuel cell are disclosed. In the first embodiment the second metal electrode is displaced away from the hollow fiber in the electrolyte body while in the second embodiment a spiral-wrap electrode is provided about the outer surface of the hollow fiber electrode.