Sample records for conduction
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Method of forming macro-structured high surface area transparent conductive oxide electrodes
Forman, Arnold J.; Chen, Zhebo; Jaramillo, Thomas F.
2016-01-05
A method of forming a high surface area transparent conducting electrode is provided that includes depositing a transparent conducting thin film on a conductive substrate, where the transparent conducting thin film includes transparent conductive particles and a solution-based transparent conducting adhesive layer which serves to coat and bind together the transparent conducting particles, and heat treating the transparent conducting adhesion layer on the conductive substrate, where an increased surface area transparent conducting electrode is formed.
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Rolled-up transformer structure for a radiofrequency integrated circuit (RFIC)
Li, Xiuling; Huang, Wen
2016-05-03
A rolled-up transformer structure comprises a multilayer sheet having a rolled configuration comprising multiple turns about a longitudinal axis. The multilayer sheet comprises more than one conductive pattern layer on a strain-relieved layer, including a first conductive film and a second conductive film separated from the first conductive film in a thickness direction. The first conductive film comprises an even number of primary conductive strips, where each primary conductive strip has a length extending in the rolling direction, and the second conductive film comprises an even number of secondary conductive strips, where each secondary conductive strip has a length extending in the rolling direction. In the rolled configuration, turns of the primary conductive strips and turns of the secondary conductive strips wrap around the longitudinal axis. The primary conductive strips serve as a primary winding and the secondary conductive strips serve as a secondary winding of the rolled-up transformer structure.
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Passive safety device and internal short tested method for energy storage cells and systems
Keyser, Matthew; Darcy, Eric; Long, Dirk; Pesaran, Ahmad
2015-09-22
A passive safety device for an energy storage cell for positioning between two electrically conductive layers of the energy storage cell. The safety device also comprising a separator and a non-conductive layer. A first electrically conductive material is provided on the non-conductive layer. A first opening is formed through the separator between the first electrically conductive material and one of the electrically conductive layers of the energy storage device. A second electrically conductive material is provided adjacent the first electrically conductive material on the non-conductive layer, wherein a space is formed on the non-conductive layer between the first and second electrically conductive materials. A second opening is formed through the non-conductive layer between the second electrically conductive material and another of the electrically conductive layers of the energy storage device. The first and second electrically conductive materials combine and exit at least partially through the first and second openings to connect the two electrically conductive layers of the energy storage device at a predetermined temperature.
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Rim, Seung Bum; Kim, Taeseok; Smith, David D; Cousins, Peter J
2013-11-12
Methods of fabricating bypass diodes for solar cells are described. In once embodiment, a method includes forming a first conductive region of a first conductivity type above a substrate of a solar cell. A second conductive region of a second conductivity type is formed on the first conductive region. In another embodiment, a method includes forming a first conductive region of a first conductivity type above a substrate of a solar cell. A second conductive region of a second conductivity type is formed within, and surrounded by, an uppermost portion of the first conductive region but is not formed in a lowermost portion of the first conductive region.
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Wang, Zhong L [Marietta, GA; Xu, Sheng [Atlanta, GA
2011-08-23
An electric power generator includes a first conductive layer, a plurality of semiconducting piezoelectric nanostructures, a second conductive layer and a plurality of conductive nanostructures. The first conductive layer has a first surface from which the semiconducting piezoelectric nanostructures extend. The second conductive layer has a second surface and is parallel to the first conductive layer so that the second surface faces the first surface of the first conductive layer. The conductive nanostructures depend downwardly therefrom. The second conductive layer is spaced apart from the first conductive layer at a distance so that when a force is applied, the semiconducting piezoelectric nanostructures engage the conductive nanostructures so that the piezoelectric nanostructures bend, thereby generating a potential difference across the at semiconducting piezoelectric nanostructures and also thereby forming a Schottky barrier between the semiconducting piezoelectric nanostructures and the conductive nanostructures.
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Rolled-up transformer structure for a radiofrequency integrated circuit (RFIC)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Xiuling; Huang, Wen
A rolled-up transformer structure comprises a multilayer sheet having a rolled configuration comprising multiple turns about a longitudinal axis. The multilayer sheet comprises more than one conductive pattern layer on a strain-relieved layer, including a first conductive film and a second conductive film separated from the first conductive film in a thickness direction. The first conductive film comprises an even number of primary conductive strips, where each primary conductive strip has a length extending in the rolling direction, and the second conductive film comprises an even number of secondary conductive strips, where each secondary conductive strip has a length extendingmore » in the rolling direction. In the rolled configuration, turns of the primary conductive strips and turns of the secondary conductive strips wrap around the longitudinal axis. The primary conductive strips serve as a primary winding and the secondary conductive strips serve as a secondary winding of the rolled-up transformer structure.« less
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Rolled-up transmission line structure for a radiofrequency integrated circuit (RFIC)
Li, Xiuling; Huang, Wen
2015-04-28
A rolled-up transmission line structure for a radiofrequency integrated circuit (RFIC) comprises a multilayer sheet in a rolled configuration comprising multiple turns about a longitudinal axis, where the multilayer sheet comprises a conductive pattern layer on a strain-relieved layer. The conductive pattern layer comprises a first conductive film and a second conductive film separated from the first conductive film in a rolling direction. In the rolled configuration, the first conductive film surrounds the longitudinal axis, and the second conductive film surrounds the first conductive film. The first conductive film serves as a signal line and the second conductive film serves as a conductive shield for the rolled-up transmission line structure.
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Rim, Seung Bum [Palo Alto, CA; Kim, Taeseok [San Jose, CA; Smith, David D [Campbell, CA; Cousins, Peter J [Menlo Park, CA
2012-03-13
Bypass diodes for solar cells are described. In one embodiment, a bypass diode for a solar cell includes a substrate of the solar cell. A first conductive region is disposed above the substrate, the first conductive region of a first conductivity type. A second conductive region is disposed on the first conductive region, the second conductive region of a second conductivity type opposite the first conductivity type.
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Johnson, Carole D.; Dawson, C.B.; Belaval, Marcel; Lane, John W.
2002-01-01
A surface-geophysical investigation to characterize the hydrogeology and contaminant distribution of the former landfill area at the University of Connecticut in Storrs, Connecticut, was conducted in 2000 to supplement the preliminary hydrogeologic assessment of the contamination of soil, surface water, and ground water at the site. A geophysical-toolbox approach was used to characterize the hydrogeology and contaminant distribution of the former landfill. Two-dimensional direct-current resistivity, inductive terrain-conductivity, and seismic-refraction surface-geophysical data were collected and interpreted in an iterative manner with exploratory drilling, borehole geophysics, and hydraulic testing. In this investigation, a geophysical-toolbox approach was used to 1) further define previously identified conductive anomalies and leachate plumes; 2) identify additional leachate plumes, possible fracture zones, and (or) conductive lithologic layers in the bedrock; and 3) delineate bedrock-surface topography in the drainage valleys north and south of the landfill. Resistivity and terrain-conductivity surveys were used to further delineate previously identified geophysical anomalies to the north and southwest of the landfill. A conductive anomaly identified in the terrain-conductivity survey to the north of the landfill in 2000 had a similar location and magnitude as an anomaly identified in terrain-conductivity surveys conducted in 1998 and 1999. Collectively, these surveys indicated that the magnitude of the conductive anomaly decreased with depth and with distance from the landfill. These anomalies indicated landfill leachate in the overburden and shallow bedrock. Results of previous surface-geophysical investigations southwest of the landfill indicated a shallow conductive anomaly in the overburden that extended into the fractured-bedrock aquifer. This conductive anomaly had a sheet-like geometry that had a north-south strike, dipped to the west, and terminated abruptly about 450 feet southwest of the landfill. The sheet-like conductive anomaly was interpreted as a fractured, conductive lithologic feature filled with conductive fluids. To further delineate this anomaly, two two-dimensional resistivity profiles were collected west of the sheet-like conductive anomaly to assess the possibility that the sheet-like conductive anomaly continued to the west in its down-dip direction. Each of the north-south oriented resistivity profiles showed bullet-shaped rather than linear-shaped anomalies, with a relatively smaller magnitude of conductivity than the sheet-like conductive anomaly to the east. If these bullet-like features are spatially connected, they may represent a linear, or pipe-like, conductive anomaly in the bedrock with a trend of N290?E and a plunge of 12?. Additional surveys were conducted to assess the apparent southern termination of the sheet-like conductive feature. Terrain-conductivity surveys indicated the sheet-like feature was not continuous to the south. A two-dimensional resistivity line and a coincident terrain-conductivity profile indicated the presence of a steep, eastward dipping, low magnitude, electrically conductive anomaly on the eastern end of the profile. Although the sheet-like conductive anomaly apparently did not continue to the south, the survey conducted in 2000 identified an isolated, weak conductive anomaly south of the previously identified anomaly. Inductive terrain-conductivity surveys performed north of the sheet-like conductive anomaly and west of the landfill indicated the anomaly did not extend to the north into the area of the former chemical-waste disposal pits. No conductive plumes or conductive features were observed in the subsurface bedrock west of the landfill. A conductive anomaly was identified in the southern section of the new terrain-conductivity grid. The magnitude and distribution of the apparent conductivity of this anomaly was identified as a nearly vertica
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Oskouyi, Amirhossein Biabangard; Sundararaj, Uttandaraman; Mertiny, Pierre
2014-01-01
In this study, a three-dimensional continuum percolation model was developed based on a Monte Carlo simulation approach to investigate the percolation behavior of an electrically insulating matrix reinforced with conductive nano-platelet fillers. The conductivity behavior of composites rendered conductive by randomly dispersed conductive platelets was modeled by developing a three-dimensional finite element resistor network. Parameters related to the percolation threshold and a power-low describing the conductivity behavior were determined. The piezoresistivity behavior of conductive composites was studied employing a reoriented resistor network emulating a conductive composite subjected to mechanical strain. The effects of the governing parameters, i.e., electron tunneling distance, conductive particle aspect ratio and size effects on conductivity behavior were examined. PMID:28788580
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Method and apparatus for casting conductive and semi-conductive materials
Ciszek, T.F.
1984-08-13
A method and apparatus is disclosed for casting conductive and semi-conductive materials. The apparatus includes a plurality of conductive members arranged to define a container-like area having a desired cross-sectional shape. A portion or all of the conductive or semi-conductive material which is to be cast is introduced into the container-like area. A means is provided for inducing the flow of an electrical current in each of the conductive members, which currents act collectively to induce a current flow in the material. The induced current flow through the conductive members is in a direction substantially opposite to the induced current flow in the material so that the material is repelled from the conductive members during the casting process.
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Appendix 3 Summary of Field Sampling and Analytical Methods with Bibliography
Conductivity and Specific conductance are measures of the ability of water to conduct an electric current, and are a general measure of stream-water quality. Conductivity is affected by temperature, with warmer water having a greater conductivity. Specific conductance is the te...
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Current collectors for improved safety
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abdelmalak, Michael Naguib; Allu, Srikanth; Dudney, Nancy J.
A battery electrode assembly includes a current collector with conduction barrier regions having a conductive state in which electrical conductivity through the conduction barrier region is permitted, and a safety state in which electrical conductivity through the conduction barrier regions is reduced. The conduction barrier regions change from the conductive state to the safety state when the current collector receives a short-threatening event. An electrode material can be connected to the current collector. The conduction barrier regions can define electrical isolation subregions. A battery is also disclosed, and methods for making the electrode assembly, methods for making a battery, andmore » methods for operating a battery.« less
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Anisotropic conductivity imaging with MREIT using equipotential projection algorithm.
Değirmenci, Evren; Eyüboğlu, B Murat
2007-12-21
Magnetic resonance electrical impedance tomography (MREIT) combines magnetic flux or current density measurements obtained by magnetic resonance imaging (MRI) and surface potential measurements to reconstruct images of true conductivity with high spatial resolution. Most of the biological tissues have anisotropic conductivity; therefore, anisotropy should be taken into account in conductivity image reconstruction. Almost all of the MREIT reconstruction algorithms proposed to date assume isotropic conductivity distribution. In this study, a novel MREIT image reconstruction algorithm is proposed to image anisotropic conductivity. Relative anisotropic conductivity values are reconstructed iteratively, using only current density measurements without any potential measurement. In order to obtain true conductivity values, only either one potential or conductivity measurement is sufficient to determine a scaling factor. The proposed technique is evaluated on simulated data for isotropic and anisotropic conductivity distributions, with and without measurement noise. Simulation results show that the images of both anisotropic and isotropic conductivity distributions can be reconstructed successfully.
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NASA Astrophysics Data System (ADS)
Dai, Lidong; Sun, Wenqing; Li, Heping; Hu, Haiying; Wu, Lei; Jiang, Jianjun
2018-03-01
The electrical conductivity of gneiss samples with different chemical compositions (WA = Na2O + K2O + CaO = 7.12, 7.27 and 7.64 % weight percent) was measured using a complex impedance spectroscopic technique at 623-1073 K and 1.5 GPa and a frequency range of 10-1 to 106 Hz. Simultaneously, a pressure effect on the electrical conductivity was also determined for the WA = 7.12 % gneiss. The results indicated that the gneiss conductivities markedly increase with total alkali and calcium ion content. The sample conductivity and temperature conform to an Arrhenius relationship within a certain temperature range. The influence of pressure on gneiss conductivity is weaker than temperature, although conductivity still increases with pressure. According to various ranges of activation enthalpy (0.35-0.52 and 0.76-0.87 eV) at 1.5 GPa, two main conduction mechanisms are suggested that dominate the electrical conductivity of gneiss: impurity conduction in the lower-temperature region and ionic conduction (charge carriers are K+, Na+ and Ca2+) in the higher-temperature region. The electrical conductivity of gneiss with various chemical compositions cannot be used to interpret the high conductivity anomalies in the Dabie-Sulu ultrahigh-pressure metamorphic belt. However, the conductivity-depth profiles for gneiss may provide an important constraint on the interpretation of field magnetotelluric conductivity results in the regional metamorphic belt.
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2017-01-01
Photosynthetic efficiency is a critical determinant of crop yield potential, although it remains below the theoretical optimum in modern crop varieties. Enhancing mesophyll conductance (i.e. the rate of carbon dioxide diffusion from substomatal cavities to the sites of carboxylation) may increase photosynthetic and water use efficiencies. To improve water use efficiency, mesophyll conductance should be increased without concomitantly increasing stomatal conductance. Here, we partition the variance in mesophyll conductance to within- and among-cultivar components across soybean (Glycine max) grown under both controlled and field conditions and examine the covariation of mesophyll conductance with photosynthetic rate, stomatal conductance, water use efficiency, and leaf mass per area. We demonstrate that mesophyll conductance varies more than 2-fold and that 38% of this variation is due to cultivar identity. As expected, mesophyll conductance is positively correlated with photosynthetic rates. However, a strong positive correlation between mesophyll and stomatal conductance among cultivars apparently impedes positive scaling between mesophyll conductance and water use efficiency in soybean. Contrary to expectations, photosynthetic rates and mesophyll conductance both increased with increasing leaf mass per area. The presence of genetic variation for mesophyll conductance suggests that there is potential to increase photosynthesis and mesophyll conductance by selecting for greater leaf mass per area. Increasing water use efficiency, though, is unlikely unless there is simultaneous stabilizing selection on stomatal conductance. PMID:28270627
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Code of Federal Regulations, 2011 CFR
2011-07-01
...' ethical conduct standards, financial disclosure and financial interests regulations and other conduct... EMPLOYEE RESPONSIBILITIES AND CONDUCT § 811.1 Cross-references to employees' ethical conduct standards... Council on Historic Preservation are subject to the executive branch-wide standards of ethical conduct...
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Code of Federal Regulations, 2010 CFR
2010-07-01
...' ethical conduct standards, financial disclosure and financial interests regulations and other conduct... EMPLOYEE RESPONSIBILITIES AND CONDUCT § 811.1 Cross-references to employees' ethical conduct standards... Council on Historic Preservation are subject to the executive branch-wide standards of ethical conduct...
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Code of Federal Regulations, 2013 CFR
2013-07-01
...' ethical conduct standards, financial disclosure and financial interests regulations and other conduct... PRESERVATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 811.1 Cross-references to employees' ethical conduct... ethical conduct, financial disclosure and financial interests regulations at 5 CFR Parts 2634, 2635 and...
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Code of Federal Regulations, 2014 CFR
2014-07-01
...' ethical conduct standards, financial disclosure and financial interests regulations and other conduct... EMPLOYEE RESPONSIBILITIES AND CONDUCT § 811.1 Cross-references to employees' ethical conduct standards... Council on Historic Preservation are subject to the executive branch-wide standards of ethical conduct...
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Code of Federal Regulations, 2012 CFR
2012-07-01
...' ethical conduct standards, financial disclosure and financial interests regulations and other conduct... EMPLOYEE RESPONSIBILITIES AND CONDUCT § 811.1 Cross-references to employees' ethical conduct standards... Council on Historic Preservation are subject to the executive branch-wide standards of ethical conduct...
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Zhu, Huayang; Ricote, Sandrine; Coors, W Grover; Kee, Robert J
2015-01-01
A model-based interpretation of measured equilibrium conductivity and conductivity relaxation is developed to establish thermodynamic, transport, and kinetics parameters for multiple charged defect conducting (MCDC) ceramic materials. The present study focuses on 10% yttrium-doped barium zirconate (BZY10). In principle, using the Nernst-Einstein relationship, equilibrium conductivity measurements are sufficient to establish thermodynamic and transport properties. However, in practice it is difficult to establish unique sets of properties using equilibrium conductivity alone. Combining equilibrium and conductivity-relaxation measurements serves to significantly improve the quantitative fidelity of the derived material properties. The models are developed using a Nernst-Planck-Poisson (NPP) formulation, which enables the quantitative representation of conductivity relaxations caused by very large changes in oxygen partial pressure.
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Electrical contact arrangement for a coating process
Kabagambe, Benjamin; McCamy, James W; Boyd, Donald W
2013-09-17
A protective coating is applied to the electrically conductive surface of a reflective coating of a solar mirror by biasing a conductive member having a layer of a malleable electrically conductive material, e.g. a paste, against a portion of the conductive surface while moving an electrodepositable coating composition over the conductive surface. The moving of the electrodepositable coating composition over the conductive surface includes moving the solar mirror through a flow curtain of the electrodepositable coating composition and submerging the solar mirror in a pool of the electrodepositable coating composition. The use of the layer of a malleable electrically conductive material between the conductive member and the conductive surface compensates for irregularities in the conductive surface being contacted during the coating process thereby reducing the current density at the electrical contact area.
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Composites incorporated a conductive polymer nanofiber network
Pozzo, Lilo Danielle; Newbloom, Gregory
2017-04-11
Methods of forming composites that incorporate networks of conductive polymer nanofibers are provided. Networks of less-than conductive polymers are first formed and then doped with a chemical dopant to provide networks of conductive polymers. The networks of conductive polymers are then incorporated into a matrix in order to improve the conductivity of the matrix. The formed composites are useful as conductive coatings for applications including electromagnetic energy management on exterior surfaces of vehicles.
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Code of Federal Regulations, 2011 CFR
2011-07-01
...' ethical conduct standards, financial disclosure regulations and other conduct rules. 400.1 Section 400.1... CONDUCT § 400.1 Cross-references to employees' ethical conduct standards, financial disclosure regulations... executive branch-wide standards of ethical conduct and financial disclosure regulations at 5 CFR parts 2634...
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Code of Federal Regulations, 2011 CFR
2011-10-01
... 45 Public Welfare 3 2011-10-01 2011-10-01 false Cross-reference to employee ethical conduct... STANDARDS OF CONDUCT FOR EMPLOYEES § 1105.1 Cross-reference to employee ethical conduct standards and... ethical conduct at 5 CFR part 2635; the executive branch employees responsibilities and conduct...
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Code of Federal Regulations, 2010 CFR
2010-10-01
... 45 Public Welfare 3 2010-10-01 2010-10-01 false Cross-reference to employee ethical conduct... STANDARDS OF CONDUCT FOR EMPLOYEES § 1105.1 Cross-reference to employee ethical conduct standards and... ethical conduct at 5 CFR part 2635; the executive branch employees responsibilities and conduct...
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Code of Federal Regulations, 2010 CFR
2010-07-01
...' ethical conduct standards, financial disclosure regulations and other conduct rules. 400.1 Section 400.1... CONDUCT § 400.1 Cross-references to employees' ethical conduct standards, financial disclosure regulations... executive branch-wide standards of ethical conduct and financial disclosure regulations at 5 CFR parts 2634...
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Code of Federal Regulations, 2014 CFR
2014-07-01
...' ethical conduct standards, financial disclosure regulations and other conduct rules. 400.1 Section 400.1... CONDUCT § 400.1 Cross-references to employees' ethical conduct standards, financial disclosure regulations... executive branch-wide standards of ethical conduct and financial disclosure regulations at 5 CFR parts 2634...
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Code of Federal Regulations, 2012 CFR
2012-10-01
... 45 Public Welfare 3 2012-10-01 2012-10-01 false Cross-reference to employee ethical conduct... STANDARDS OF CONDUCT FOR EMPLOYEES § 1105.1 Cross-reference to employee ethical conduct standards and... ethical conduct at 5 CFR part 2635; the executive branch employees responsibilities and conduct...
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Code of Federal Regulations, 2013 CFR
2013-10-01
... 45 Public Welfare 3 2013-10-01 2013-10-01 false Cross-reference to employee ethical conduct... STANDARDS OF CONDUCT FOR EMPLOYEES § 1105.1 Cross-reference to employee ethical conduct standards and... ethical conduct at 5 CFR part 2635; the executive branch employees responsibilities and conduct...
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Code of Federal Regulations, 2014 CFR
2014-10-01
... 45 Public Welfare 3 2014-10-01 2014-10-01 false Cross-reference to employee ethical conduct... STANDARDS OF CONDUCT FOR EMPLOYEES § 1105.1 Cross-reference to employee ethical conduct standards and... ethical conduct at 5 CFR part 2635; the executive branch employees responsibilities and conduct...
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Code of Federal Regulations, 2012 CFR
2012-07-01
...' ethical conduct standards, financial disclosure regulations and other conduct rules. 400.1 Section 400.1... CONDUCT § 400.1 Cross-references to employees' ethical conduct standards, financial disclosure regulations... executive branch-wide standards of ethical conduct and financial disclosure regulations at 5 CFR parts 2634...
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Jang, Bor Z [Centerville, OH; Zhamu, Aruna [Centerville, OH; Guo, Jiusheng [Centerville, OH
2011-02-15
This invention provides a moldable, multiple-layer composite composition, which is a precursor to an electrically conductive composite flow field plate or bipolar plate. In one preferred embodiment, the composition comprises a plurality of conductive sheets and a plurality of mixture layers of a curable resin and conductive fillers, wherein (A) each conductive sheet is attached to at least one resin-filler mixture layer; (B) at least one of the conductive sheets comprises flexible graphite; and (C) at least one resin-filler mixture layer comprises a thermosetting resin and conductive fillers with the fillers being present in a sufficient quantity to render the resulting flow field plate or bipolar plate electrically conductive with a conductivity no less than 100 S/cm and thickness-direction areal conductivity no less than 200 S/cm.sup.2.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Elizondo-Decanini, Juan M.
Short pulse neutron generators are described herein. In a general embodiment, the short pulse neutron generator includes a Blumlein structure. The Blumlein structure includes a first conductive plate, a second conductive plate, a third conductive plate, at least one of an inductor or a resistor, a switch, and a dielectric material. The first conductive plate is positioned relative to the second conductive plate such that a gap separates these plates. A vacuum chamber is positioned in the gap, and an ion source is positioned to emit ions in the vacuum chamber. The third conductive plate is electrically grounded, and themore » switch is operable to electrically connect and disconnect the second conductive plate and the third conductive plate. The at least one of the resistor or the inductor is coupled to the first conductive plate and the second conductive plate.« less
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NASA Astrophysics Data System (ADS)
Bourdo, Shawn Edward
Two groups of materials that have recently come to the forefront of research initiatives are carbon allotropes, especially nanotubes, and conducting polymers-more specifically inherently conducting polymers. The terms conducting polymers and inherently conducting polymers sometimes are used interchangeably without fully acknowledging a major difference in these terms. Conducting polymers (CPs) and inherently conducting polymers (ICPs) are both polymeric materials that conduct electricity, but the difference lies in how each of these materials conducts electricity. For CPs of the past, an electrically conductive filler such as metal particles, carbon black, or graphite would be blended into a polymer (insulator) allowing for the CP to carry an electric current. An ICP conducts electricity due to the intrinsic nature of its chemical structure. The two materials at the center of this research are graphite and polyaniline. For the first time, a composite between carbon allotropes (graphite) and an inherently conducting polymer (PANI) has exhibited an electrical conductivity greater than either of the two components. Both components have a plethora of potential applications and therefore the further investigation could lead to use of these composites in any number of technologies. Touted applications that use either conductive carbons or ICPs exist in a wide range of fields, including electromagnetic interference (EMI) shielding, radar evasion, low power rechargeable batteries, electrostatic dissipation (ESD) for anti-static textiles, electronic devices, light emitting diodes (LEDs), corrosion prevention, gas sensors, super capacitors, photovoltaic cells, and resistive heating. The main motivation for this research has been to investigate the connection between an observed increase in conductivity and structure of composites. Two main findings have resulted from the research as related to the observed increase in conductivity. The first was the structural evidence from Raman spectroscopy, X-ray diffraction, and thermal analysis suggesting a more crystalline graphite matrix due to intimate interactions with PANI that resulted in a charge transfer. Confirmation of charge transfer was observed through magnetic susceptibility, electron paramagnetic resonance, and temperature dependent electrical conductivity studies.
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NASA Astrophysics Data System (ADS)
Nguyen, S. T.; Vu, M.-H.; Vu, M. N.; Tang, A. M.
2017-05-01
The present work aims to modeling the thermal conductivity of fractured materials using homogenization-based analytical and pattern-based numerical methods. These materials are considered as a network of cracks distributed inside a solid matrix. Heat flow through such media is perturbed by the crack system. The problem of heat flow across a single crack is firstly investigated. The classical Eshelby's solution, extended to the thermal conduction problem of an ellipsoidal inclusion embedding in an infinite homogeneous matrix, gives an analytical solution of temperature discontinuity across a non-conducting penny-shaped crack. This solution is then validated by the numerical simulation based on the finite elements method. The numerical simulation allows analyzing the effect of crack conductivity. The problem of a single crack is then extended to a medium containing multiple cracks. Analytical estimations for effective thermal conductivity, that take into account the interaction between cracks and their spatial distribution, are developed for the case of non-conducting cracks. Pattern-based numerical method is then employed for both cases non-conducting and conducting cracks. In the case of non-conducting cracks, numerical and analytical methods, both account for the spatial distribution of the cracks, fit perfectly. In the case of conducting cracks, the numerical analyzing of crack conductivity effect shows that highly conducting cracks weakly affect heat flow and the effective thermal conductivity of fractured media.
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Code of Federal Regulations, 2013 CFR
2013-07-01
...' ethical conduct standards, financial disclosure regulations and other conduct rules. § 400.1 Section Â... RESPONSIBILITIES AND CONDUCT § 400.1 Cross-references to employees' ethical conduct standards, financial disclosure... executive branch-wide standards of ethical conduct and financial disclosure regulations at 5 CFR parts 2634...
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McKinnell, James A; Miller, Loren; Singh, Raveena D; Mendez, Job; Franco, Ryan; Gussin, Gabrielle; Chang, Justin; Dutciuc, Tabitha D; Saavedra, Raheeb; Kleinman, Ken; Peterson, Ellena M; Evans, Kaye D; Heim, Lauren; Miner, Aaron; Estevez, Marlene; Custodio, Harold; Yamaguchi, Stacey; Nguyen, Jenny; Varasteh, Alex; Launer, Bryn; Agrawal, Shalini; Tjoa, Thomas; He, Jiayi; Park, Steven; Tam, Steven; Gohil, Shruti K; Stone, Nimalie D; Steinberg, Karl; Montgomery, Jocelyn; Beecham, Nancy; Huang, Susan S
2017-01-01
Abstract Background The majority of healthcare-associated infections due to MDROs occur in the post-discharge setting. Understanding MDRO spread and containment in NHs can help identify infection prevention activities needed to care for vulnerable patients in a medical home setting. Methods We conducted a baseline point prevalence study of MDRO colonization in residents of 28 Southern California NHs participating in a decolonization trial. In Fall 2016, residents were randomly sampled to obtain a set of 50 nares and skin (axilla/groin) swabs from each NH. Nasal swabs were processed for MRSA and skin swabs were processed for MRSA, VRE, ESBL, and CRE. In addition, environmental swabs were collected from high touch objects in resident rooms (bedrail, call button/TV remote, door knobs, light switch, bathroom) and common areas (nursing station, table, chair, railing, and drinking fountain). Results A total of 2,797 body swabs were obtained from 1400 residents. Overall, 48.6% (N = 680) of residents harbored MDROs. MRSA was found in 37% of residents (29.5% nares, 24.4% skin), followed by ESBL in 16% (Table 1). Resident MDRO status was only known for 11% of MRSA (59/518), 18% ESBL (40/228), 4% VRE (4/99), and none of the CRE (0/13) carriers. Colonization did not differ between long stay (48.8%, 534/1094) vs. post-acute (47.7%, 146/306) residents (P = NS), but bedbound residents were more likely to be MDRO colonized (58.7%, 182/310) vs. ambulatory residents (45.7%, 497/1088, P < 0.001). A total of 560 environmental swabs were obtained with 93% of common areas and 74% of resident rooms having an MDRO+ object with an average of 2.5 and 1.9 objects found to be contaminated (Table 2). Conclusion One in two NH residents are colonized with MDROs, which is largely unknown to the facility. MDRO carriage is associated with total care needs, but not long stay status. Environmental contamination in resident rooms and common areas is common. The burden of MDRO colonization and contamination is sufficiently high that universal strategies to reduce colonization and transmission are warranted. Disclosures J. A. McKinnell, Allergan: Research Contractor, Scientific Advisor and Speaker’s Bureau, Consulting fee, Research support and Speaker honorarium; Achaogen: Research Contractor, Scientific Advisor and Shareholder, Research support; Cempra: Research Contractor and Scientific Advisor, Research support; Theravance: Research Contractor, Research support; Science 37: Research Contractor, Salary; Expert Stewardship, LLC: Board Member and Employee, Salary; Thermo Fisher: Scientific Advisor, Salary; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; L. Miller, 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; R. D. Singh, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; J. Mendez, Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; R. Franco, Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; G. Gussin, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; L’Oreal: Consultant, Consulting fee; J. Chang, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; T. D. Dutciuc, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; R. Saavedra, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; K. Kleinman, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Molnlycke: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; E. M. Peterson, Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; L. Heim, Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; A. Miner, Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; M. Estevez, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; H. Custodio, Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; S. Yamaguchi, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; J. Nguyen, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; A. Varasteh, Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Product: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; B. Launer, 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; S. Agrawal, Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; T. Tjoa, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; J. He, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; S. Park, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; S. Tam, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; S. K. Gohil, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; S. S. Huang, Sage Products: Receipt of contributed product, Conducting studies in which participating healthcare facilities are receiving contributed product (no contribution in submitted abstract), Participating healthcare facilities in my studies received contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in which participating healthcare facilities are receiving contributed product (no contribution in submitted abstract), Participating healthcare facilities in my studies received contributed product; Clorox: Receipt of contributed product, Conducting studies in which participating healthcare facilities are receiving contributed product (no contribution in submitted abstract), Participating healthcare facilities in my studies received contributed product; 3M: Receipt of contributed product, Conducting studies in which participating healthcare facilities are receiving contributed product (no contribution in submitted abstract), Participating healthcare facilities in my studies received contributed product; Molnlycke: Receipt of contributed product, Conducting studies in which participating healthcare facilities are receiving contributed product (no contribution in submitted abstract), Participating healthcare facilities in my studies received contributed product
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Sensitive bridge circuit measures conductance of low-conductivity electrolyte solutions
NASA Technical Reports Server (NTRS)
Schmidt, K.
1967-01-01
Compact bridge circuit measures sensitive and accurate conductance of low-conductivity electrolyte solutions. The bridge utilizes a phase sensitive detector to obtain a linear deflection of the null indicator relative to the measured conductance.
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Current conducting end plate of fuel cell assembly
Walsh, Michael M.
1999-01-01
A fuel cell assembly has a current conducting end plate with a conductive body formed integrally with isolating material. The conductive body has a first surface, a second surface opposite the first surface, and an electrical connector. The first surface has an exposed portion for conducting current between a working section of the fuel cell assembly and the electrical connector. The isolating material is positioned on at least a portion of the second surface. The conductive body can have support passage(s) extending therethrough for receiving structural member(s) of the fuel cell assembly. Isolating material can electrically isolate the conductive body from the structural member(s). The conductive body can have service passage(s) extending therethrough for servicing one or more fluids for the fuel cell assembly. Isolating material can chemically isolate the one or more fluids from the conductive body. The isolating material can also electrically isolate the conductive body from the one or more fluids.
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Park, Han-Saem; Ko, Seo-Jin; Park, Jeong-Seok; Kim, Jin Young; Song, Hyun-Kon
2013-01-01
Electric conductivity of conducting polymers has been steadily enhanced towards a level worthy of being called its alias, “synthetic metal”. PEDOT:PSS (poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate)), as a representative conducting polymer, recently reached around 3,000 S cm−1, the value to open the possibility to replace transparent conductive oxides. The leading strategy to drive the conductivity increase is solvent annealing in which aqueous solution of PEDOT:PSS is treated with an assistant solvent such as DMSO (dimethyl sulfoxide). In addition to the conductivity enhancement, we found that the potential range in which PEDOT:PSS is conductive is tuned wider into a negative potential direction by the DMSO-annealing. Also, the increase in a redox-active fraction of charge carriers is proposed to be responsible for the enhancement of conductivity in the solvent annealing process. PMID:23949091
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Apparatus and Method for Generating Thrust Using a Two Dimensional, Asymmetrical Capacitor Module
NASA Technical Reports Server (NTRS)
Campbell, Jonathan W. (Inventor)
2001-01-01
A capacitor module system is provided for creating a thrust force. The system includes a capacitor module provided with a first conductive element having a cylindrical geometry. The first conductive element can be a hollow cylinder or a solid cylinder. The capacitor module also includes a second conductive element axially spaced from the first conductive element and of smaller axial extent. The second conductive element can be a flat disk, a dome, or a conductive tip at the end of a dielectric rod. A dielectric element is disposed between the first conductive element and the second conductive element. The system also includes a high voltage source having first and second terminals connected respectively to the first and second conductive elements. The high voltage source applies a high voltage to the conductive elements of sufficient value to create a thrust force on the module inducing movement thereof.
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Xie, Xufen; Yan, Jiawei; Liang, Jinghong; Li, Jijun; Zhang, Meng; Mao, Bingwei
2013-10-01
We present quantum conductance measurements of germanium by means of an electrochemical scanning tunneling microscope (STM) break junction based on a jump-to-contact mechanism. Germanium nanowires between a platinum/iridium tip and different substrates were constructed to measure the quantum conductance. By applying appropriate potentials to the substrate and the tip, the process of heterogeneous contact and homogeneous breakage was realized. Typical conductance traces exhibit steps at 0.025 and 0.05 G0. The conductance histogram indicates that the conductance of germanium nanowires is located between 0.02 and 0.15 G0 in the low-conductance region and is free from the influence of substrate materials. However, the distribution of conductance plateaus is too discrete to display distinct peaks in the conductance histogram of the high-conductance region. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Ceramic substrate including thin film multilayer surface conductor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wolf, Joseph Ambrose; Peterson, Kenneth A.
2017-05-09
A ceramic substrate comprises a plurality of ceramic sheets, a plurality of inner conductive layers, a plurality of vias, and an upper conductive layer. The ceramic sheets are stacked one on top of another and include a top ceramic sheet. The inner conductive layers include electrically conductive material that forms electrically conductive features on an upper surface of each ceramic sheet excluding the top ceramic sheet. The vias are formed in each of the ceramic sheets with each via being filled with electrically conductive material. The upper conductive layer includes electrically conductive material that forms electrically conductive features on anmore » upper surface of the top ceramic sheet. The upper conductive layer is constructed from a stack of four sublayers. A first sublayer is formed from titanium. A second sublayer is formed from copper. A third sublayer is formed from platinum. A fourth sublayer is formed from gold.« less
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Allen, Ranulfo; Pan, Lijia; Fuller, Gerald G; Bao, Zhenan
2014-07-09
Single-walled carbon nanotubes/polymer composites typically have limited conductivity due to a low concentration of nanotubes and the insulating nature of the polymers used. Here we combined a method to align carbon nanotubes with in-situ polymerization of conductive polymer to form composite films and fibers. Use of the conducting polymer raised the conductivity of the films by 2 orders of magnitude. On the other hand, CNT fiber formation was made possible with in-situ polymerization to provide more mechanical support to the CNTs from the formed conducting polymer. The carbon nanotube/conductive polymer composite films and fibers had conductivities of 3300 and 170 S/cm, respectively. The relatively high conductivities were attributed to the polymerization process, which doped both the SWNTs and the polymer. In-situ polymerization can be a promising solution-processable method to enhance the conductivity of carbon nanotube films and fibers.
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Golner, Thomas M.; Mehta, Shirish P.
2005-07-26
A method and apparatus for connecting high voltage leads to a super-conducting transformer is provided that includes a first super-conducting coil set, a second super-conducting coil set, and a third super-conducting coil set. The first, second and third super-conducting coil sets are connected via an insulated interconnect system that includes insulated conductors and insulated connectors that are utilized to connect the first, second, and third super-conducting coil sets to the high voltage leads.
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Behaviour of conductivity improvers in jet fuel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dacre, B.; Hetherington, J.I.
1995-05-01
Dangerous accumulation of electrostatic charge can occur due to high speed pumping and microfiltration of fuel. This can be avoided by increasing the electrical conductivity of the fuel using conductivity improver additives. However, marked variations occur in the conductivity response of different fuels when doped to the same level with conductivity improver. This has been attributed to interactions of the conductivity improver with other fuel additives or fuel contaminants. The present work concentrates on the effects of fuel contaminants, in particular polar compounds, on the performance of the conductivity improver. Conductivity is the fuel property of prime interest. The conductivitymore » response of model systems of the conductivity improver STADIS 450 in dodecane has been measured and the effect on this conductivity of additions of model polar contaminants sodium naphthenate, sodium dodecyl benzene sulphonate, and sodium phenate have been measured. The sodium salts have been found to have a complex effect on the performance of STADIS 450, reducing the conductivity at low concentrations to a minimum value and then increasing the conductivity at high concentrations of sodium salts. This work has focused on characterising this minimum in the conductivity values and on understanding the reason for its occurrence. The effects on the minimum conductivity value of the following parameters are investigated: (a) time, (b) STADIS 450 concentration, (c) sodium salt concentration, (d) mixed sodium salts, (e) experimental method, (f) a phenol, (g) individual components of STADIS 450. The complex conductivity response of the STADIS 450 to sodium salt impurities is discussed in terms of possible inter-molecular interactions.« less
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Singh, Raveena D; Jernigan, John A; Slayton, Rachel B; Stone, Nimalie D; McKinnell, James A; Miller, Loren G; Kleinman, Ken; Heim, Lauren; Dutciuc, Tabitha D; Estevez, Marlene; Gussin, Gabrielle; Chang, Justin; Peterson, Ellena M; Evans, Kaye D; Lee, Bruce Y; Mueller, Leslie E; Bartsch, Sarah M; Zahn, Matthew; Janssen, Lynn; Weinstein, Robert A; Hayden, Mary K; Gohil, Shruti K; Park, Steven; Tam, Steven; Saavedra, Raheeb; Yamaguchi, Stacey; Custodio, Harold; Nguyen, Jenny; Tjoa, Thomas; He, Jiayi; O’Donnell, Kathleen; Coady, Micaela H; Platt, Richard; Huang, Susan S
2017-01-01
Abstract Background MDROs can spread between hospitals, nursing homes (NH), and long-term acute care facilities (LTACs) via shared patients. SHIELD OC is a regional decolonization collaborative involving 38 of 104 countywide adult facilities identified by their high degree of direct and indirect patient sharing with one another. We report baseline MDRO prevalence in these facilities. Methods Adult patients in 38 facilities (17 hospitals, 18 NHs, 3 LTACs) underwent point-prevalence screening between September 2016–April 2017 for MRSA, VRE, ESBL, and CRE using nares, skin (axilla/groin), and peri-rectal swabs. In NHs and LTACs, residents were randomly selected until 50 sets of swabs were obtained. Swabbing in hospitals involved all patients in contact precautions. An additional set of swabs were also performed for all LTAC admissions from November 2016–February 2017. Results The overall prevalence of any MDRO among patients was 64% (44%–88%) in NHs, 80% (range 72%–86%) in LTACs, and 64% (54–84%) in hospitals (contact precaution patients) (Table 1). Only 25%, 64%, and 81% of patients were already known to harbor an MDRO in NHs, LTACs, and hospitals, respectively. Known MDRO patients also harbored another MDRO 49%, 63%, and 34% of the time for NHs, LTACs, and hospitals, respectively. In LTACs, MDRO point prevalence was 38% higher than the usual admission prevalence (65% higher for MRSA, 34% higher for VRE, 95% higher for ESBL, and 50% higher for CRE). Conclusion MDRO carriage in highly inter-connected NHs and LTACs was widespread, rivaling that found in hospitalized patients on contact precautions. MRSA, VRE, and ESBL carriage far outnumbered CRE carriage. A history of MDRO was insensitive for identifying MDRO carriers, and many patients carried multiple MDROs. The extensive MDRO burden and transmission in long-term care settings suggests that regional MDRO prevention efforts must include MDRO control in long-term care facilities. Disclosures R. D. Singh, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; J. A. McKinnell, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; L. G. Miller, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; K. Kleinman, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Molnlycke: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; L. Heim, Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; T. D. Dutciuc, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; M. Estevez, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; G. Gussin, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; L’Oreal: Consultant, Consulting fee; J. Chang, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; E. M. Peterson, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; B. Y. Lee, GSK: Consultant, Consulting fee; R. A. Weinstein, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Molnlycke: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; OpGen Company: Study support, Provided services at no charge; M. K. Hayden, Sage Products: Receipt of contributed product, Sage is contributing product to healthcare facilities participating in a regional collaborative on which I am a co-investigator. Neither I nor my hospital receive product.; Clorox: Receipt of contributed product, Research support; CDC: Grant Investigator and Receipt of contributed product, Research grant; Molnlycke: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; OpGen Company: Study support, Provided services at no charge for studies; S. K. Gohil, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; S. Park, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; S. Tam, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; R. Saavedra, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; S. Yamaguchi, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; H. Custodio, Xttrium Laboratories: Study coordination, Conducting studies in healthcare facilities that are receiving contributed product; Sage Products: Study coordination, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Study coordination, Conducting studies in healthcare facilities that are receiving contributed product; J. Nguyen, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; T. Tjoa, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; J. He, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; 3M: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; M. H. Coady, Sage Products: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Molnlycke: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; Clorox: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; R. Platt, Sage Products: Receipt of contributed product, Conducting clinical studies in which participating healthcare facilities are receiving contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting clinical studies in which participating healthcare facilities are receiving contributed product; Clorox: Receipt of contributed product, Conducting clinical studies in which participating healthcare facilities are receiving contributed product; receive research funds from Clorox, but Clorox has no role in the design; Molnlycke: Receipt of contributed product, Conducting studies in healthcare facilities that are receiving contributed product; S. S. Huang, Sage Products: Receipt of contributed product, Conducting studies in which participating healthcare facilities are receiving contributed product (no contribution in submitted abstract), Participating healthcare facilities in my studies received contributed product; Xttrium Laboratories: Receipt of contributed product, Conducting studies in which participating healthcare facilities are receiving contributed product (no contribution in submitted abstract), Participating healthcare facilities in my studies received contributed product; Clorox: Receipt of contributed product, Conducting studies in which participating healthcare facilities are receiving contributed product (no contribution in submitted abstract), Participating healthcare facilities in my studies received contributed product; 3M: Receipt of contributed product, Conducting studies in which participating healthcare facilities are receiving contributed product (no contribution in submitted abstract), Participating healthcare facilities in my studies received contributed product; Molnlycke: Receipt of contributed product, Conducting studies in which participating healthcare facilities are receiving contributed product (no contribution in submitted abstract), Participating healthcare facilities in my studies received contributed product
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Tooker, Angela C.; Felix, Sarah H.; Pannu, Satinderpall S.
A neural interface includes a first dielectric material having at least one first opening for a first electrical conducting material, a first electrical conducting material in the first opening, and at least one first interconnection trace electrical conducting material connected to the first electrical conducting material. A stiffening shank material is located adjacent the first dielectric material, the first electrical conducting material, and the first interconnection trace electrical conducting material.
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NASA Technical Reports Server (NTRS)
Prud'Homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor)
2011-01-01
A conductive ink containing a conductive polymer, wherein the conductive polymer contains at least one polymer and a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m/g, and it use in a method for making a conductive circuit.
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Materials and methods for autonomous restoration of electrical conductivity
Blaiszik, Benjamin J; Odom, Susan A; Caruso, Mary M; Jackson, Aaron C; Baginska, Marta B; Ritchey, Joshua A; Finke, Aaron D; White, Scott R; Moore, Jeffrey S; Sottos, Nancy R; Braun, Paul V; Amine, Khalil
2014-03-25
An autonomic conductivity restoration system includes a solid conductor and a plurality of particles. The particles include a conductive fluid, a plurality of conductive microparticles, and/or a conductive material forming agent. The solid conductor has a first end, a second end, and a first conductivity between the first and second ends. When a crack forms between the first and second ends of the conductor, the contents of at least a portion of the particles are released into the crack. The cracked conductor and the released contents of the particles form a restored conductor having a second conductivity, which may be at least 90% of the first conductivity.
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Voltage-Induced Nonlinear Conduction Properties of Epoxy Resin/Micron-Silver Particles Composites
NASA Astrophysics Data System (ADS)
Qu, Zhaoming; Lu, Pin; Yuan, Yang; Wang, Qingguo
2018-01-01
The nonlinear conduction properties of epoxy resin (ER)/micron-silver particles (MP) composites were investigated. Under sufficient high intensity applied constant voltage, the obvious nonlinear conduction properties of the samples with volume fraction 25% were found. With increments in the voltage, the conductive switching effect was observed. The nonlinear conduction mechanism of the ER/MP composites under high applied voltages could be attributed to the electrical current conducted via discrete paths of conductive particles induced by the electric field. The test results show that the ER/MP composites with nonlinear conduction properties are of great potential application in electromagnetic protection of electron devices and systems.
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Electrical and Thermal Conductivity and Conduction Mechanism of Ge2Sb2Te5 Alloy
NASA Astrophysics Data System (ADS)
Lan, Rui; Endo, Rie; Kuwahara, Masashi; Kobayashi, Yoshinao; Susa, Masahiro
2017-11-01
Ge2Sb2Te5 alloy has drawn much attention due to its application in phase-change random-access memory and potential as a thermoelectric material. Electrical and thermal conductivity are important material properties in both applications. The aim of this work is to investigate the temperature dependence of the electrical and thermal conductivity of Ge2Sb2Te5 alloy and discuss the thermal conduction mechanism. The electrical resistivity and thermal conductivity of Ge2Sb2Te5 alloy were measured from room temperature to 823 K by four-terminal and hot-strip method, respectively. With increasing temperature, the electrical resistivity increased while the thermal conductivity first decreased up to about 600 K then increased. The electronic component of the thermal conductivity was calculated from the Wiedemann-Franz law using the resistivity results. At room temperature, Ge2Sb2Te5 alloy has large electronic thermal conductivity and low lattice thermal conductivity. Bipolar diffusion contributes more to the thermal conductivity with increasing temperature. The special crystallographic structure of Ge2Sb2Te5 alloy accounts for the thermal conduction mechanism.
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Electrical and Thermal Conductivity and Conduction Mechanism of Ge2Sb2Te5 Alloy
NASA Astrophysics Data System (ADS)
Lan, Rui; Endo, Rie; Kuwahara, Masashi; Kobayashi, Yoshinao; Susa, Masahiro
2018-06-01
Ge2Sb2Te5 alloy has drawn much attention due to its application in phase-change random-access memory and potential as a thermoelectric material. Electrical and thermal conductivity are important material properties in both applications. The aim of this work is to investigate the temperature dependence of the electrical and thermal conductivity of Ge2Sb2Te5 alloy and discuss the thermal conduction mechanism. The electrical resistivity and thermal conductivity of Ge2Sb2Te5 alloy were measured from room temperature to 823 K by four-terminal and hot-strip method, respectively. With increasing temperature, the electrical resistivity increased while the thermal conductivity first decreased up to about 600 K then increased. The electronic component of the thermal conductivity was calculated from the Wiedemann-Franz law using the resistivity results. At room temperature, Ge2Sb2Te5 alloy has large electronic thermal conductivity and low lattice thermal conductivity. Bipolar diffusion contributes more to the thermal conductivity with increasing temperature. The special crystallographic structure of Ge2Sb2Te5 alloy accounts for the thermal conduction mechanism.
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Campbell, Jeremy B [Torrance, CA; Newson, Steve [Redondo Beach, CA
2011-11-15
A power module assembly of the type suitable for deployment in a vehicular power inverter, wherein the power inverter has a grounded chassis, is provided. The power module assembly comprises a conductive base layer electrically coupled to the chassis, an insulating layer disposed on the conductive base layer, a first conductive node disposed on the insulating layer, a second conductive node disposed on the insulating layer, wherein the first and second conductive nodes are electrically isolated from each other. The power module assembly also comprises a first capacitor having a first electrode electrically connected to the conductive base layer, and a second electrode electrically connected to the first conductive node, and further comprises a second capacitor having a first electrode electrically connected to the conductive base layer, and a second electrode electrically connected to the second conductive node.
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Recovery of Ventriculo-Atrial Conduction after Adrenaline in Patients Implanted with Pacemakers.
Cismaru, Gabriel; Gusetu, Gabriel; Muresan, Lucian; Rosu, Radu; Andronache, Marius; Matuz, Roxana; Puiu, Mihai; Mester, Petru; Miclaus, Maria; Pop, Dana; Mircea, Petru Adrian; Zdrenghea, Dumitru
2015-07-01
Ventriculo-atrial (VA) conduction can have negative consequences for patients with implanted pacemakers and defibrillators. There is concern whether impaired VA conduction could recover during stressful situations. Although the influence of isoproterenol and atropine are well established, the effect of adrenaline has not been studied systematically. The objective of this study was to determine if adrenaline can facilitate recovery of VA conduction in patients implanted with pacemakers. A prospective study was conducted on 61 consecutive patients during a 4-month period (April-July 2014). The presence of VA conduction was assessed during the pacemaker implantation procedure. In case of an impaired VA conduction, adrenaline infusio was used as a stress surrogate to test conduction recovery. The indications for pacemaker implantation were: sinus node dysfunction in 18 patients, atrioventricular (AV) block in 40 patients, binodal dysfunction (sinus node+ AV node) in two patients and other (carotid sinus syndrome) in one patient. In the basal state, 15/61 (24.6%) presented spontaneous VA conduction and 46/61 (75.4%) had no VA conduction. After administration of adrenaline, there was VA conduction recovery in 5/46 (10.9%) patients. Adrenaline infusion produced recovery of VA conduction in 10.9% of patients with absent VA conduction in a basal state. Recovery of VA conduction during physiological or pathological stresses could be responsible for the pacemaker syndrome, PMT episodes, or certain implantable cardiac defibrillator detection issues. © 2015 Wiley Periodicals, Inc.
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Conducting Compositions of Matter
NASA Technical Reports Server (NTRS)
Viswanathan, Tito (Inventor)
1999-01-01
The invention provides conductive compositions of matter, as well as methods for the preparation of the conductive compositions of matter, solutions comprising the conductive compositions of matter, and methods of preparing fibers or fabrics having improved anti-static properties employing the conductive compositions of matter.
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Conducting Compositions of Matter
NASA Technical Reports Server (NTRS)
Viswanathan, Tito (Inventor)
2001-01-01
The invention provides conductive compositions of matter, as well as methods for the preparation of the conductive compositions of matter, solutions comprising the conductive compositions of matter, and methods of preparing fibers or fabrics having improved anti-static properties employing the conductive compositions of matter.
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Conducting compositions of matter
NASA Technical Reports Server (NTRS)
Viswanathan, Tito (Inventor)
2000-01-01
The invention provides conductive compositions of matter, as well as methods for the preparation of the conductive compositions of matter, solutions comprising the conductive compositions of matter, and methods of preparing fibers or fabrics having improved anti-static properties employing the conductive compositions of matter.
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High thermal conductivity materials for thermal management applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Broido, David A.; Reinecke, Thomas L.; Lindsay, Lucas R.
High thermal conductivity materials and methods of their use for thermal management applications are provided. In some embodiments, a device comprises a heat generating unit (304) and a thermally conductive unit (306, 308, 310) in thermal communication with the heat generating unit (304) for conducting heat generated by the heat generating unit (304) away from the heat generating unit (304), the thermally conductive unit (306, 308, 310) comprising a thermally conductive compound, alloy or composite thereof. The thermally conductive compound may include Boron Arsenide, Boron Antimonide, Germanium Carbide and Beryllium Selenide.
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In-Situ Wire Damage Detection System
NASA Technical Reports Server (NTRS)
Jolley, Scott T. (Inventor); Gibson, Tracy L. (Inventor); Medelius, Pedro J. (Inventor); Roberson, Luke B. (Inventor); Tate, Lanetra C. (Inventor); Smith, Trent M. (Inventor); Williams, Martha K. (Inventor)
2014-01-01
An in-situ system for detecting damage in an electrically conductive wire. The system includes a substrate at least partially covered by a layer of electrically conductive material forming a continuous or non-continuous electrically conductive layer connected to an electrical signal generator adapted to delivering electrical signals to the electrically conductive layer. Data is received and processed to identify damage to the substrate or electrically conductive layer. The electrically conductive material may include metalized carbon fibers, a thin metal coating, a conductive polymer, carbon nanotubes, metal nanoparticles or a combination thereof.
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Making Complex Electrically Conductive Patterns on Cloth
NASA Technical Reports Server (NTRS)
Chu, Andrew; Fink, Patrick W.; Dobbins, Justin A.; Lin, Greg Y.; Scully, Robert C.; Trevino, Robert
2008-01-01
A method for automated fabrication of flexible, electrically conductive patterns on cloth substrates has been demonstrated. Products developed using this method, or related prior methods, are instances of a technology known as 'e-textiles,' in which electrically conductive patterns ar formed in, and on, textiles. For many applications, including high-speed digital circuits, antennas, and radio frequency (RF) circuits, an e-textile method should be capable of providing high surface conductivity, tight tolerances for control of characteristic impedances, and geometrically complex conductive patterns. Unlike prior methods, the present method satisfies all three of these criteria. Typical patterns can include such circuit structures as RF transmission lines, antennas, filters, and other conductive patterns equivalent to those of conventional printed circuits. The present method overcomes the limitations of the prior methods for forming the equivalent of printed circuits on cloth. A typical fabrication process according to the present method involves selecting the appropriate conductive and non-conductive fabric layers to build the e-textile circuit. The present method uses commercially available woven conductive cloth with established surface conductivity specifications. Dielectric constant, loss tangent, and thickness are some of the parameters to be considered for the non-conductive fabric layers. The circuit design of the conductive woven fabric is secured onto a non-conductive fabric layer using sewing, embroidery, and/or adhesive means. The portion of the conductive fabric that is not part of the circuit is next cut from the desired circuit using an automated machine such as a printed-circuit-board milling machine or a laser cutting machine. Fiducials can be used to align the circuit and the cutting machine. Multilayer circuits can be built starting with the inner layer and using conductive thread to make electrical connections between layers.
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Khadem, Masoud H; Wemhoff, Aaron P
2013-02-28
Non-equilibrium molecular dynamics (NEMD) simulations are used to investigate the thermal conductivity of herringbone graphite nanofibers (GNFs) at room temperature by breaking down the axial and transverse conductivity values into intralayer and interlayer components. The optimized Tersoff potential is used to account for intralayer carbon-carbon interactions while the Lennard-Jones potential is used to model the interlayer carbon-carbon interactions. The intralayer thermal conductivity of the graphene layers near room temperature is calculated for different crease angles and number of layers using NEMD with a constant applied heat flux. The edge effect on a layer's thermal conductivity is investigated by computing the thermal conductivity values in both zigzag and armchair directions of the heat flow. The interlayer thermal conductivity is also predicted by imposing hot and cold Nosé-Hoover thermostats on two layers. The limiting case of a 90° crease angle is used to compare the results with those of single-layer graphene and few-layer graphene. The axial and transverse thermal conductivities are then calculated using standard trigonometric conversions of the calculated intralayer and interlayer thermal conductivities, along with calculations of few-layer graphene without a crease. The results show a large influence of the crease angle on the intralayer thermal conductivity, and the saturation of thermal conductivity occurs when number of layers is more than three. The axial thermal conductivity, transverse thermal conductivity in the crease direction, and transverse thermal conductivity normal to the crease for the case of a five-layer herringbone GNF with a 45° crease angle are calculated to be 27 W∕m K, 263 W∕m K, and 1500 W∕m K, respectively, where the axial thermal conductivity is in good agreement with experimental measurements.
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Regulation of Kv2.1 K+ conductance by cell surface channel density
Fox, Philip D.; Loftus, Rob J.; Tamkun, Michael M.
2013-01-01
The Kv2.1 voltage-gated K+ channel is found both freely diffusing over the plasma membrane and concentrated in micron-sized clusters localized to the soma, proximal dendrites and axon initial segment of hippocampal neurons. In transfected HEK cells, Kv2.1 channels within cluster microdomains are non-conducting. Using TIRF microscopy the number of GFP-tagged Kv2.1 channels on the HEK cell surface was compared to K+ channel conductance measured by whole-cell voltage-clamp of the same cell. This approach indicated that as channel density increases non-clustered channels cease conducting. At the highest density observed, only 4% of all channels were conducting. Mutant Kv2.1 channels that fail to cluster also possessed the non-conducting state with 17% conducting K+ at higher surface densities. The non-conducting state was specific to Kv2.1 as Kv1.4 was always conducting regardless of the cell-surface expression level. Anti-Kv2.1 immuno-fluorescence intensity, standardized to Kv2.1 surface density in transfected HEK cells, was used to determine the expression levels of endogenous Kv2.1 in cultured rat hippocampal neurons. Endogenous Kv2.1 levels were compared to the number of conducting channels determined by whole-cell voltage clamp. Only 13 and 27% of the endogenous Kv2.1 was conducting in neurons cultured for 14 and 20 days, respectively. Together these data indicate that the non-conducting state depends primarily on surface density as opposed to cluster location and that this non-conducting state also exists for native Kv2.1 found in cultured hippocampal neurons. This excess of Kv2.1 protein relative to K+ conductance further supports a non-conducting role for Kv2.1 in excitable tissues. PMID:23325261
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The symmetry of single-molecule conduction.
Solomon, Gemma C; Gagliardi, Alessio; Pecchia, Alessandro; Frauenheim, Thomas; Di Carlo, Aldo; Reimers, Jeffrey R; Hush, Noel S
2006-11-14
We introduce the conductance point group which defines the symmetry of single-molecule conduction within the nonequilibrium Green's function formalism. It is shown, either rigorously or to within a very good approximation, to correspond to a molecular-conductance point group defined purely in terms of the properties of the conducting molecule. This enables single-molecule conductivity to be described in terms of key qualitative chemical descriptors that are independent of the nature of the molecule-conductor interfaces. We apply this to demonstrate how symmetry controls the conduction through 1,4-benzenedithiol chemisorbed to gold electrodes as an example system, listing also the molecular-conductance point groups for a range of molecules commonly used in molecular electronics research.
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NASA Technical Reports Server (NTRS)
Chamberlain, Neil F. (Inventor); Zawadzki, Mark S. (Inventor); Hodges, Richard E. (Inventor)
2012-01-01
Disclosed herein is a patch antenna comprises a planar conductive patch attached to a ground plane by a support member, and a probe connector in electrical communication with the conductive patch arranged to conduct electromagnetic energy to or from the conductive patch, wherein the conductive patch is disposed essentially parallel to the ground plane and is separated from the ground plane by a spacing distance; wherein the support member comprises a plurality of sides disposed about a central axis oriented perpendicular to the conductive patch and the ground plane; wherein the conductive patch is solely supported above the ground plane by the support member; and wherein the support member provides electrical communication between the planer conductive patch and the ground plane.
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Method and system for pipeline communication
Richardson,; John, G [Idaho Falls, ID
2008-01-29
A pipeline communication system and method includes a pipeline having a surface extending along at least a portion of the length of the pipeline. A conductive bus is formed to and extends along a portion of the surface of the pipeline. The conductive bus includes a first conductive trace and a second conductive trace with the first and second conductive traces being adapted to conformally couple with a pipeline at the surface extending along at least a portion of the length of the pipeline. A transmitter for sending information along the conductive bus on the pipeline is coupled thereto and a receiver for receiving the information from the conductive bus on the pipeline is also couple to the conductive bus.
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Rolled-up inductor structure for a radiofrequency integrated circuit (RFIC)
Li, Xiuling; Huang, Wen; Ferreira, Placid M.; Yu, Xin
2015-12-29
A rolled-up inductor structure for a radiofrequency integrated circuit (RFIC) comprises a multilayer sheet in a rolled configuration comprising multiple turns about a longitudinal axis. The multilayer sheet comprises a conductive pattern layer on a strain-relieved layer, and the conductive pattern layer comprises at least one conductive strip having a length extending in a rolling direction. The at least one conductive strip thereby wraps around the longitudinal axis in the rolled configuration. The conductive pattern layer may also comprise two conductive feed lines connected to the conductive strip for passage of electrical current therethrough. The conductive strip serves as an inductor cell of the rolled-up inductor structure.
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Fabric circuits and method of manufacturing fabric circuits
NASA Technical Reports Server (NTRS)
Chu, Andrew W. (Inventor); Dobbins, Justin A. (Inventor); Scully, Robert C. (Inventor); Trevino, Robert C. (Inventor); Lin, Greg Y. (Inventor); Fink, Patrick W. (Inventor)
2011-01-01
A flexible, fabric-based circuit comprises a non-conductive flexible layer of fabric and a conductive flexible layer of fabric adjacent thereto. A non-conductive thread, an adhesive, and/or other means may be used for attaching the conductive layer to the non-conductive layer. In some embodiments, the layers are attached by a computer-driven embroidery machine at pre-determined portions or locations in accordance with a pre-determined attachment layout before automated cutting. In some other embodiments, an automated milling machine or a computer-driven laser using a pre-designed circuit trace as a template cuts the conductive layer so as to separate an undesired portion of the conductive layer from a desired portion of the conductive layer. Additional layers of conductive fabric may be attached in some embodiments to form a multi-layer construct.
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Electrical Switchability and Dry-Wash Durability of Conductive Textiles
Wu, Bangting; Zhang, Bowu; Wu, Jingxia; Wang, Ziqiang; Ma, Hongjuan; Yu, Ming; Li, Linfan; Li, Jingye
2015-01-01
There is growing interest in the area of conductive textiles in the scientific and industrial community. Herein, we successfully prepared a conductive textile via covalently grafting polyaniline (PANI) onto cotton by a multi-step treatment process. The conductivity of the resultant fabric could be tuned by immersing in water having different pH values. The conductive and insulating properties of the textile could be conveniently switched by alternately immersing in acidic and alkaline bath solutions. Most importantly, the resultant conductive fabrics were able to withstand 40 simulated dry-wash cycles, with almost no decay in the electrical conductivity, indicating their excellent dry-wash durability. The present strategy for fabricating conductive fabrics with excellent switchability of electrical properties and dry-wash durability is expected to provide inspiration for the production of multifunctional conductive textiles for use in hash or sensitive conditions. PMID:26066704
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32 CFR 1903.14 - Disorderly conduct.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 32 National Defense 6 2012-07-01 2012-07-01 false Disorderly conduct. 1903.14 Section 1903.14 National Defense Other Regulations Relating to National Defense CENTRAL INTELLIGENCE AGENCY CONDUCT ON AGENCY INSTALLATIONS § 1903.14 Disorderly conduct. A person commits disorderly conduct when, with intent...
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32 CFR 1903.14 - Disorderly conduct.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 32 National Defense 6 2010-07-01 2010-07-01 false Disorderly conduct. 1903.14 Section 1903.14 National Defense Other Regulations Relating to National Defense CENTRAL INTELLIGENCE AGENCY CONDUCT ON AGENCY INSTALLATIONS § 1903.14 Disorderly conduct. A person commits disorderly conduct when, with intent...
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32 CFR 1903.14 - Disorderly conduct.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 32 National Defense 6 2013-07-01 2013-07-01 false Disorderly conduct. 1903.14 Section 1903.14 National Defense Other Regulations Relating to National Defense CENTRAL INTELLIGENCE AGENCY CONDUCT ON AGENCY INSTALLATIONS § 1903.14 Disorderly conduct. A person commits disorderly conduct when, with intent...
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32 CFR 1903.14 - Disorderly conduct.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 32 National Defense 6 2014-07-01 2014-07-01 false Disorderly conduct. 1903.14 Section 1903.14 National Defense Other Regulations Relating to National Defense CENTRAL INTELLIGENCE AGENCY CONDUCT ON AGENCY INSTALLATIONS § 1903.14 Disorderly conduct. A person commits disorderly conduct when, with intent...
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32 CFR 1903.14 - Disorderly conduct.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 32 National Defense 6 2011-07-01 2011-07-01 false Disorderly conduct. 1903.14 Section 1903.14 National Defense Other Regulations Relating to National Defense CENTRAL INTELLIGENCE AGENCY CONDUCT ON AGENCY INSTALLATIONS § 1903.14 Disorderly conduct. A person commits disorderly conduct when, with intent...
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38 CFR 21.8360 - Satisfactory conduct and cooperation.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Satisfactory conduct and... Children of Vietnam Veterans-Spina Bifida and Covered Birth Defects Satisfactory Conduct and Cooperation § 21.8360 Satisfactory conduct and cooperation. The provisions for satisfactory conduct and cooperation...
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Three-dimensional protonic conductivity in porous organic cage solids.
Liu, Ming; Chen, Linjiang; Lewis, Scott; Chong, Samantha Y; Little, Marc A; Hasell, Tom; Aldous, Iain M; Brown, Craig M; Smith, Martin W; Morrison, Carole A; Hardwick, Laurence J; Cooper, Andrew I
2016-09-13
Proton conduction is a fundamental process in biology and in devices such as proton exchange membrane fuel cells. To maximize proton conduction, three-dimensional conduction pathways are preferred over one-dimensional pathways, which prevent conduction in two dimensions. Many crystalline porous solids to date show one-dimensional proton conduction. Here we report porous molecular cages with proton conductivities (up to 10(-3) S cm(-1) at high relative humidity) that compete with extended metal-organic frameworks. The structure of the organic cage imposes a conduction pathway that is necessarily three-dimensional. The cage molecules also promote proton transfer by confining the water molecules while being sufficiently flexible to allow hydrogen bond reorganization. The proton conduction is explained at the molecular level through a combination of proton conductivity measurements, crystallography, molecular simulations and quasi-elastic neutron scattering. These results provide a starting point for high-temperature, anhydrous proton conductors through inclusion of guests other than water in the cage pores.
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Schulz-Heik, R Jay; Rhee, Soo Hyun; Silvern, Louise E; Haberstick, Brett C; Hopfer, Christian; Lessem, Jeffrey M; Hewitt, John K
2010-05-01
It is often assumed that childhood maltreatment causes conduct problems via an environmentally mediated process. However, the association may be due alternatively to either a nonpassive gene-environment correlation, in which parents react to children's genetically-influenced conduct problems by maltreating them, or a passive gene-environment correlation, in which parents' tendency to engage in maltreatment and children's conduct problems are both influenced by a hereditary vulnerability to antisocial behavior (i.e. genetic mediation). The present study estimated the contribution of these processes to the association between maltreatment and conduct problems. Bivariate behavior genetic analyses were conducted on approximately 1,650 twin and sibling pairs drawn from a large longitudinal study of adolescent health (Add Health). The correlation between maltreatment and conduct problems was small; much of the association between maltreatment and conduct problems was due to a nonpassive gene-environment correlation. Results were more consistent with the hypothesis that parents respond to children's genetically-influenced conduct problems by maltreating them than the hypothesis that maltreatment causes conduct problems.
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Three-dimensional protonic conductivity in porous organic cage solids
NASA Astrophysics Data System (ADS)
Liu, Ming; Chen, Linjiang; Lewis, Scott; Chong, Samantha Y.; Little, Marc A.; Hasell, Tom; Aldous, Iain M.; Brown, Craig M.; Smith, Martin W.; Morrison, Carole A.; Hardwick, Laurence J.; Cooper, Andrew I.
2016-09-01
Proton conduction is a fundamental process in biology and in devices such as proton exchange membrane fuel cells. To maximize proton conduction, three-dimensional conduction pathways are preferred over one-dimensional pathways, which prevent conduction in two dimensions. Many crystalline porous solids to date show one-dimensional proton conduction. Here we report porous molecular cages with proton conductivities (up to 10-3 S cm-1 at high relative humidity) that compete with extended metal-organic frameworks. The structure of the organic cage imposes a conduction pathway that is necessarily three-dimensional. The cage molecules also promote proton transfer by confining the water molecules while being sufficiently flexible to allow hydrogen bond reorganization. The proton conduction is explained at the molecular level through a combination of proton conductivity measurements, crystallography, molecular simulations and quasi-elastic neutron scattering. These results provide a starting point for high-temperature, anhydrous proton conductors through inclusion of guests other than water in the cage pores.
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Nerve conduction studies are safe in patients with central venous catheters.
London, Zachary N; Mundwiler, Andrew; Oral, Hakan; Gallagher, Gary W
2017-08-01
It is unknown if central venous catheters bypass the skin's electrical resistance and engender a risk of nerve conduction study-induced cardiac arrhythmia. The objective of this study is to determine if nerve conduction studies affect cardiac conduction and rhythm in patients with central venous catheters. Under continuous 12-lead electrocardiogram monitoring, subjects with and without central venous catheters underwent a series of upper extremity nerve conduction studies. A cardiologist reviewed the electrocardiogram tracings for evidence of cardiac conduction abnormality or arrhythmia. Ten control subjects and 10 subjects with central venous catheters underwent the nerve conduction study protocol. No malignant arrhythmias or conduction abnormalities were noted in either group. Nerve conduction studies of the upper extremities, including both proximal stimulation and repetitive stimulation, do not appear to confer increased risk of cardiac conduction abnormality in those patients with central venous catheters who are not critically ill or have a prior history of arrhythmia. Muscle Nerve 56: 321-323, 2017. © 2016 Wiley Periodicals, Inc.
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NASA Astrophysics Data System (ADS)
Revil, André; Soueid Ahmed, Abdellahi
2017-11-01
Umezawa et al. investigated the dependence of the electrical conductivity of rocks with respect to the saturation of the water phase. Four issues can be underlined in their work: (1) The conductivity model they used mixes bulk and surface tortuosities in the same linear equation (i.e., between the conductivity and the conductivity of the pore water). This conflicts with the fact that the conductivity is a concave down increasing function of the pore water conductivity and bulk tortuosity is defined only at high salinity while surface tortuosity is defined only at very low salinity. (2) The specific surface conductance obtained by Umezawa et al. is too low and conflicts with independent evaluations obtained with double layer models for aluminosilicates and silicates. (3) The expression given for the resistivity index conflicts with the inclusion of a surface conductivity term in the conductivity equation.
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Low resistance thin film organic solar cell electrodes
Forrest, Stephen [Princeton, NJ; Xue, Jiangeng [Piscataway, NJ
2008-01-01
A method which lower the series resistance of photosensitive devices includes providing a transparent film of a first electrically conductive material arranged on a transparent substrate; depositing and patterning a mask over the first electrically conductive material, such that openings in the mask have sloping sides which narrow approaching the substrate; depositing a second electrically conductive material directly onto the first electrically conductive material exposed in the openings of the mask, at least partially filling the openings; stripping the mask, leaving behind reentrant structures of the second electrically conductive material which were formed by the deposits in the openings of the mask; after stripping the mask, depositing a first organic material onto the first electrically conductive material in between the reentrant structures; and directionally depositing a third electrically conductive material over the first organic material deposited in between the reentrant structures, edges of the reentrant structures aligning deposition so that the third electrically conductive material does not directly contact the first electrically conductive material, and does not directly contact the second electrically conductive material.
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Cooling apparatus with a resilient heat conducting member
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chainer, Timothy J.; Parida, Pritish R.; Schultz, Mark D.
2016-06-14
A cooling structure including a thermally conducting central element having a channel formed therein, the channel being configured for flow of cooling fluid there through, a first pressure plate, and a first thermally conductive resilient member disposed between the thermally conducting central element and the first pressure plate, wherein the first pressure plate, the first thermally conductive resilient member, and the thermally conducting central element form a first heat transfer path.
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Flexible neural interfaces with integrated stiffening shank
Tooker, Angela C.; Felix, Sarah H.; Pannu, Satinderpall S.; Shah, Kedar G.; Sheth, Heeral; Tolosa, Vanessa
2016-07-26
A neural interface includes a first dielectric material having at least one first opening for a first electrical conducting material, a first electrical conducting material in the first opening, and at least one first interconnection trace electrical conducting material connected to the first electrical conducting material. A stiffening shank material is located adjacent the first dielectric material, the first electrical conducting material, and the first interconnection trace electrical conducting material.
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Proton conducting membrane using a solid acid
NASA Technical Reports Server (NTRS)
Boysen, Dane A. (Inventor); Narayanan, Sekharipuram R. (Inventor); Haile, Sossina M. (Inventor); Chisholm, Calum (Inventor)
2006-01-01
A solid acid material is used as a proton conducting membrane in an electrochemical device. The solid acid material can be one of a plurality of different kinds of materials. A binder can be added, and that binder can be either a nonconducting or a conducting binder. Nonconducting binders can be, for example, a polymer or a glass. A conducting binder enables the device to be both proton conducting and electron conducting.
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Electronically conducting metal oxide nanoparticles and films for optical sensing applications
Ohodnicki, Jr., Paul R.; Wang, Congjun; Andio, Mark A
2014-09-16
The disclosure relates to a method of detecting a change in a chemical composition by contacting a conducting oxide material with a monitored stream, illuminating the conducting oxide material with incident light, collecting exiting light, monitoring an optical signal based on a comparison of the incident light and the exiting light, and detecting a shift in the optical signal. The conducting metal oxide has a carrier concentration of at least 10.sup.17/cm.sup.3, a bandgap of at least 2 eV, and an electronic conductivity of at least 10.sup.-1 S/cm, where parameters are specified at the gas stream temperature. The optical response of the conducting oxide materials is proposed to result from the high carrier concentration and electronic conductivity of the conducting metal oxide, and the resulting impact of changing gas atmospheres on that relatively high carrier concentration and electronic conductivity. These changes in effective carrier densities and electronic conductivity of conducting metal oxide films and nanoparticles are postulated to be responsible for the change in measured optical absorption associated with free carriers. Exemplary conducting metal oxides include but are not limited to Al-doped ZnO, Sn-doped In.sub.2O.sub.3, Nb-doped TiO.sub.2, and F-doped SnO.sub.2.
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Apparatus for Use in Determining Surface Conductivity at Microwave Frequencies
NASA Technical Reports Server (NTRS)
Hearn, Chase P. (Inventor)
1995-01-01
An apparatus is provided for use in determining surface conductivity of a flat or shaped conductive material at microwave frequencies. A plate has an electrically conductive surface with first and second holes passing through the plate. An electrically conductive material under test (MUT) is maintained in a spaced apart relationship with the electrically conductive surface of the plate by one or more nonconductive spacers. A first coupling loop is electrically shielded within the first hole while a second coupling loop is electrically shielded within the second hole. A dielectric resonator element is positioned between the first and second coupling loops, while also being positioned closer to the MUT than the electrically conductive surface of the plate. Microwave energy at an operating frequency f is supplied from a signal source to the first coupling loop while microwave energy received at the second coupling loop is measured. The apparatus is capable of measuring the Q-factor of the dielectric resonator situated in the 'cavity' existing between the electrically conductive surface of the plate and the MUT. Surface conductivity of the electrically conductive surface can be determined via interpolation using: 1 ) the measured Q-factor with the electrically conductive surface in place, and 2) the measured Q-factor when the MUT is replaced with reference standards having known surface conductivities.
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NASA Astrophysics Data System (ADS)
Ren, Zongqing; Lee, Jaeho
2018-01-01
Artificial nanostructures have improved prospects of thermoelectric systems by enabling selective scattering of phonons and demonstrating significant thermal conductivity reductions. While the low thermal conductivity provides necessary temperature gradients for thermoelectric conversion, the heat generation is detrimental to electronic systems where high thermal conductivity are preferred. The contrasting needs of thermal conductivity are evident in thermoelectric cooling systems, which call for a fundamental breakthrough. Here we show a silicon nanostructure with vertically etched holes, or holey silicon, uniquely combines the low thermal conductivity in the in-plane direction and the high thermal conductivity in the cross-plane direction, and that the anisotropy is ideal for lateral thermoelectric cooling. The low in-plane thermal conductivity due to substantial phonon boundary scattering in small necks sustains large temperature gradients for lateral Peltier junctions. The high cross-plane thermal conductivity due to persistent long-wavelength phonons effectively dissipates heat from a hot spot to the on-chip cooling system. Our scaling analysis based on spectral phonon properties captures the anisotropic size effects in holey silicon and predicts the thermal conductivity anisotropy ratio up to 20. Our numerical simulations demonstrate the thermoelectric cooling effectiveness of holey silicon is at least 30% greater than that of high-thermal-conductivity bulk silicon and 400% greater than that of low-thermal-conductivity chalcogenides; these results contrast with the conventional perception preferring either high or low thermal conductivity materials. The thermal conductivity anisotropy is even more favorable in laterally confined systems and will provide effective thermal management solutions for advanced electronics.
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Ren, Zongqing; Lee, Jaeho
2018-01-26
Artificial nanostructures have improved prospects of thermoelectric systems by enabling selective scattering of phonons and demonstrating significant thermal conductivity reductions. While the low thermal conductivity provides necessary temperature gradients for thermoelectric conversion, the heat generation is detrimental to electronic systems where high thermal conductivity are preferred. The contrasting needs of thermal conductivity are evident in thermoelectric cooling systems, which call for a fundamental breakthrough. Here we show a silicon nanostructure with vertically etched holes, or holey silicon, uniquely combines the low thermal conductivity in the in-plane direction and the high thermal conductivity in the cross-plane direction, and that the anisotropy is ideal for lateral thermoelectric cooling. The low in-plane thermal conductivity due to substantial phonon boundary scattering in small necks sustains large temperature gradients for lateral Peltier junctions. The high cross-plane thermal conductivity due to persistent long-wavelength phonons effectively dissipates heat from a hot spot to the on-chip cooling system. Our scaling analysis based on spectral phonon properties captures the anisotropic size effects in holey silicon and predicts the thermal conductivity anisotropy ratio up to 20. Our numerical simulations demonstrate the thermoelectric cooling effectiveness of holey silicon is at least 30% greater than that of high-thermal-conductivity bulk silicon and 400% greater than that of low-thermal-conductivity chalcogenides; these results contrast with the conventional perception preferring either high or low thermal conductivity materials. The thermal conductivity anisotropy is even more favorable in laterally confined systems and will provide effective thermal management solutions for advanced electronics.
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A Model of Thermal Conductivity for Planetary Soils: 1. Theory for Unconsolidated Soils
NASA Technical Reports Server (NTRS)
Piqueux, S.; Christensen, P. R.
2009-01-01
We present a model of heat conduction for mono-sized spherical particulate media under stagnant gases based on the kinetic theory of gases, numerical modeling of Fourier s law of heat conduction, theoretical constraints on the gas thermal conductivity at various Knudsen regimes, and laboratory measurements. Incorporating the effect of the temperature allows for the derivation of the pore-filling gas conductivity and bulk thermal conductivity of samples using additional parameters (pressure, gas composition, grain size, and porosity). The radiative and solid-to-solid conductivities are also accounted for. Our thermal model reproduces the well-established bulk thermal conductivity dependency of a sample with the grain size and pressure and also confirms laboratory measurements finding that higher porosities generally lead to lower conductivities. It predicts the existence of the plateau conductivity at high pressure, where the bulk conductivity does not depend on the grain size. The good agreement between the model predictions and published laboratory measurements under a variety of pressures, temperatures, gas compositions, and grain sizes provides additional confidence in our results. On Venus, Earth, and Titan, the pressure and temperature combinations are too high to observe a soil thermal conductivity dependency on the grain size, but each planet has a unique thermal inertia due to their different surface temperatures. On Mars, the temperature and pressure combination is ideal to observe the soil thermal conductivity dependency on the average grain size. Thermal conductivity models that do not take the temperature and the pore-filling gas composition into account may yield significant errors.
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38 CFR 21.362 - Satisfactory conduct and cooperation.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Satisfactory conduct and.... Chapter 31 Conduct and Cooperation § 21.362 Satisfactory conduct and cooperation. (a) General. The... satisfactory conduct and cooperation in developing and implementing a program of rehabilitation services under...
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Conductivity is a measure of the ability of water to pass an electrical current. Because dissolved salts and other inorganic chemicals conduct electrical current, conductivity increases as salinity increases.
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36 CFR 905.735-201 - General standards of conduct.
Code of Federal Regulations, 2010 CFR
2010-07-01
... economy; (4) Losing complete independence or impartiality; (5) Making a Government decision outside... CORPORATION STANDARDS OF CONDUCT Conduct and Responsibilities of Employees § 905.735-201 General standards of conduct. (a) All employees shall conduct themselves on the job so as to efficiently discharge the work of...
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36 CFR 702.2 - Conduct on Library premises.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Conduct on Library premises. 702.2 Section 702.2 Parks, Forests, and Public Property LIBRARY OF CONGRESS CONDUCT ON LIBRARY PREMISES § 702.2 Conduct on Library premises. (a) All persons using the premises shall conduct themselves...
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21 CFR 868.5140 - Anesthesia conduction kit.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Anesthesia conduction kit. 868.5140 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5140 Anesthesia conduction kit. (a) Identification. An anesthesia conduction kit is a device used to administer to a patient conduction, regional, or...
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21 CFR 868.5140 - Anesthesia conduction kit.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Anesthesia conduction kit. 868.5140 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5140 Anesthesia conduction kit. (a) Identification. An anesthesia conduction kit is a device used to administer to a patient conduction, regional, or...
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36 CFR 702.2 - Conduct on Library premises.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Conduct on Library premises. 702.2 Section 702.2 Parks, Forests, and Public Property LIBRARY OF CONGRESS CONDUCT ON LIBRARY PREMISES § 702.2 Conduct on Library premises. (a) All persons using the premises shall conduct themselves...
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36 CFR 702.2 - Conduct on Library premises.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Conduct on Library premises. 702.2 Section 702.2 Parks, Forests, and Public Property LIBRARY OF CONGRESS CONDUCT ON LIBRARY PREMISES § 702.2 Conduct on Library premises. (a) All persons using the premises shall conduct themselves...
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21 CFR 868.5140 - Anesthesia conduction kit.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Anesthesia conduction kit. 868.5140 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5140 Anesthesia conduction kit. (a) Identification. An anesthesia conduction kit is a device used to administer to a patient conduction, regional, or...
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Electrical Conductivity of Ferritin Proteins by Conductive AFM
NASA Technical Reports Server (NTRS)
Xu, Degao; Watt, Gerald D.; Harb, John N.; Davis, Robert C.
2005-01-01
Electrical conductivity measurements were performed on single apoferritin and holoferritin molecules by conductive atomic force microscopy. Conductivity of self-assembled monolayer films of ferritin molecules on gold surfaces was also measured. Holoferritin was 5-25 times more conductive than apoferritin, indicating that for holoferritin most electron-transfer goes through the ferrihydrite core. With 1 V applied, the average electrical currents through single holoferritin and apoferritin molecules were 2.6 PA and 0.19 PA, respectively.
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Extremely High Thermal Conductivity of Aligned Carbon Nanotube-Polyethylene Composites.
Liao, Quanwen; Liu, Zhichun; Liu, Wei; Deng, Chengcheng; Yang, Nuo
2015-11-10
The ultra-low thermal conductivity of bulk polymers may be enhanced by combining them with high thermal conductivity materials such as carbon nanotubes. Different from random doping, we find that the aligned carbon nanotube-polyethylene composites has a high thermal conductivity by non-equilibrium molecular dynamics simulations. The analyses indicate that the aligned composite not only take advantage of the high thermal conduction of carbon nanotubes, but enhance thermal conduction of polyethylene chains.
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Conduction properties of thin films from a water soluble carbon nanotube/hemicellulose complex
NASA Astrophysics Data System (ADS)
Shao, Dongkai; Yotprayoonsak, Peerapong; Saunajoki, Ville; Ahlskog, Markus; Virtanen, Jorma; Kangas, Veijo; Volodin, Alexander; Van Haesendonck, Chris; Burdanova, Maria; Mosley, Connor D. W.; Lloyd-Hughes, James
2018-04-01
We have examined the conductive properties of carbon nanotube based thin films, which were prepared via dispersion in water by non-covalent functionalization of the nanotubes with xylan, a type of hemicellulose. Measurements of low temperature conductivity, Kelvin probe force microscopy, and high frequency (THz) conductivity elucidated the intra-tube and inter-tube charge transport processes in this material. The measurements show excellent conductive properties of the as prepared thin films, with bulk conductivity up to 2000 S cm-1. The transport results demonstrate that the hemicellulose does not seriously interfere with the inter-tube conductance.
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Pacemaker mediated tachycardia as a complication of the autointrinsic conduction search function.
Dennis, Malcolm J; Sparks, Paul B
2004-06-01
The autointrinsic conduction search (AICS) option, featured on some DDD pacemakers, performs periodic assessments of atrioventricular (AV) conduction capability during a single beat AV delay extension. Demonstration of ventricular conduction during the prolonged AV delay, permits ongoing AV delay extension if the patient's intrinsic conduction is preferred to ventricular pacing. A case is presented where the wide separation of atrial and ventricular pacing during the conduction search permitted retrograde ventriculoatrial conduction, precipitating pacemaker mediated tachycardia (PMT) on seven occasions in one patient. Two onset patterns are reported, both attributable to the AICS option. Recommendations for prevention strategies are made.
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Liu, Gao
2017-07-11
Embodiments of the present invention disclose a composition of matter comprising a silicon (Si) nanoparticle coated with a conductive polymer. Another embodiment discloses a method for preparing a composition of matter comprising a plurality of silicon (Si) nanoparticles coated with a conductive polymer comprising providing Si nanoparticles, providing a conductive polymer, preparing a Si nanoparticle, conductive polymer, and solvent slurry, spraying the slurry into a liquid medium that is a non-solvent of the conductive polymer, and precipitating the silicon (Si) nanoparticles coated with the conductive polymer. Another embodiment discloses an anode comprising a current collector, and a composition of matter comprising a silicon (Si) nanoparticle coated with a conductive polymer.
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Conducting Polymer Nanostructures: Template Synthesis and Applications in Energy Storage
Pan, Lijia; Qiu, Hao; Dou, Chunmeng; Li, Yun; Pu, Lin; Xu, Jianbin; Shi, Yi
2010-01-01
Conducting polymer nanostructures have received increasing attention in both fundamental research and various application fields in recent decades. Compared with bulk conducting polymers, conducting polymer nanostructures are expected to display improved performance in energy storage because of the unique properties arising from their nanoscaled size: high electrical conductivity, large surface area, short path lengths for the transport of ions, and high electrochemical activity. Template methods are emerging for a sort of facile, efficient, and highly controllable synthesis of conducting polymer nanostructures. This paper reviews template synthesis routes for conducting polymer nanostructures, including soft and hard template methods, as well as its mechanisms. The application of conducting polymer mesostructures in energy storage devices, such as supercapacitors and rechargeable batteries, are discussed. PMID:20717527
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Conducting polymer nanostructures: template synthesis and applications in energy storage.
Pan, Lijia; Qiu, Hao; Dou, Chunmeng; Li, Yun; Pu, Lin; Xu, Jianbin; Shi, Yi
2010-07-02
Conducting polymer nanostructures have received increasing attention in both fundamental research and various application fields in recent decades. Compared with bulk conducting polymers, conducting polymer nanostructures are expected to display improved performance in energy storage because of the unique properties arising from their nanoscaled size: high electrical conductivity, large surface area, short path lengths for the transport of ions, and high electrochemical activity. Template methods are emerging for a sort of facile, efficient, and highly controllable synthesis of conducting polymer nanostructures. This paper reviews template synthesis routes for conducting polymer nanostructures, including soft and hard template methods, as well as its mechanisms. The application of conducting polymer mesostructures in energy storage devices, such as supercapacitors and rechargeable batteries, are discussed.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
He, Qinggang; Kusoglu, Ahmet; Lucas, Ivan T.
2011-08-01
The objective of this effort was to correlate the local surface ionic conductance of a Nafion? 212 proton-exchange membrane with its bulk and interfacial transport properties as a function of water content. Both macroscopic and microscopic proton conductivities were investigated at different relative humidity levels, using electrochemical impedance spectroscopy and current-sensing atomic force microscopy (CSAFM). We were able to identify small ion-conducting domains that grew with humidity at the surface of the membrane. Numerical analysis of the surface ionic conductance images recorded at various relative humidity levels helped determine the fractional area of ion-conducting active sites. A simple square-root relationshipmore » between the fractional conducting area and observed interfacial mass-transport resistance was established. Furthermore, the relationship between the bulk ionic conductivity and surface ionic conductance pattern of the Nafion? membrane was examined.« less
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Interface-Controlled Conductive Fibers for Wearable Strain Sensors and Stretchable Conducting Wires.
Cao, Zherui; Wang, Ranran; He, Tengyu; Xu, Fangfang; Sun, Jing
2018-04-25
As an important subfield of flexible electronics, conductive fibers have been an active area of research. The interfacial interaction between nanostructured conductive materials with elastic substrates plays a vital role in the electromechanical performance of conductive fibers. However, the underlying mechanism has seldom been investigated. Here, we propose a fabricating strategy for a silver nanowire (Ag NW)/polyurethane composite fiber with a sheath-core architecture. The interfacial bonding layer is regulated, and its influence on the performance of conductive fibers is investigated, based on which an interfacial interaction model is proposed. The model underlines the significance of the embedding depth of the Ag NW network. Both supersensitive (gauge factor up to 9557) and ultrastable (negligible conductance degradation below the strain of 150%) conductive fibers are obtained via interface regulating, exhibiting great potential in the applications of wearable sensors and stretchable conducting connections.
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Effect of Diluent on Ultra-low Temperature Curable Conductive Silver Adhesive
NASA Astrophysics Data System (ADS)
Zhou, Xingli; Wang, Likun; Liao, Qingwei; Yan, Chao; Du, Haibo; Qin, Lei
2018-03-01
The ultra-low temperature curable conductive silver adhesive needed urgently for the surface conductive treatment of piezoelectric composite material. The effect of diluent acetone on ultra-low temperature curable conductive silver adhesive were investigated for surface conductive treatment of piezoelectric composite material. In order to improve the operability and extend the life of the conductive adhesive, the diluent was added to dissolve and disperse conductive adhesive. With the increase of the content of diluent, the volume resistivity of conductive adhesive decreased at first and then increased, and the shear strength increased at first and then decreased. When the acetone content is 10%, the silver flaky bonded together, arranged the neatest, the smallest gap, the most closely connected, the surface can form a complete conductive network, and the volume resistivity is 2.37 × 10-4Ω · cm, the shear strength is 5.13MPa.
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Upper mantle electrical conductivity for seven subcontinental regions of the Earth
Campbell, W.H.; Schiffmacher, E.R.
1988-01-01
Spherical harmonic analysis coefficients of the external and internal parts of the quiet-day geomagnetic field variations (Sq) separated for the 7 continental regions of the observatories have been used to determine conductivity profiles to depths of about 600 km by the Schmucker equivalent substitute conductor method. The profiles give evidence of increases in conductivity between about 150 and 350 km depth, then a general increase in conductivity thereafter. For South America we found a high conductivity at shallow depths. The European profile showed a highly conducting layer near 125 km. At the greater depths, Europe, Australia and South America had the lowest values of conductivity. North America and east Asia had intermediate values whereas the African and central Asian profiles both showed the conductivities rising rapidly beyond 450 km depth. The regional differences indicate that there may be considerable lateral heterogeneity of electrical conductivity in the Earth's upper mantle. -Authors
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Enhanced field-dependent conductivity of magnetorheological gels with low-doped carbon nanotubes
NASA Astrophysics Data System (ADS)
Qu, Hang; Yu, Miao; Fu, Jie; Yang, Pingan; Liu, Yuxuan
2017-10-01
Magnetorheological gels (MRG) exhibit field-dependent conductivity and controllable mechanical properties. In order to extend their application field, filling a large number of traditional conductive materials is the most common means to enhance the poor conductivity of MRG. In this study, the conductivity of MRG is improved by low-doped carbon nanotubes (CNTs). The influence of CNTs on the magnetoresistance of MRG is discussed from two aspects—the improvement in electrical conductivity and the magnetic sensitivity of conductivity variation. The percolation threshold of CNTs in MRG should be between 1 wt% and 2 wt%. The conductivity of a 4 wt% CNT-doped sample increases more than 28 000 times compared with pure MRG. However, there is a cliff-like drop for the range and rate of conductivity variation when the doping amount of CNTs is between 3 wt% and 4 wt%. Therefore, it is concluded that the optimal mass fraction of CNTs is 3%, which can maintain a suitable variation range and a strong conductivity. Compared with pure MRG, its conductivity increases by at least two orders of magnitude. Finally, a sketch of particle motion simulation is developed to understand the improving mechanism and the effect of CNTs.
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Magneto-acousto-electrical Measurement Based Electrical Conductivity Reconstruction for Tissues.
Zhou, Yan; Ma, Qingyu; Guo, Gepu; Tu, Juan; Zhang, Dong
2018-05-01
Based on the interaction of ultrasonic excitation and magnetoelectrical induction, magneto-acousto-electrical (MAE) technology was demonstrated to have the capability of differentiating conductivity variations along the acoustic transmission. By applying the characteristics of the MAE voltage, a simplified algorithm of MAE measurement based conductivity reconstruction was developed. With the analyses of acoustic vibration, ultrasound propagation, Hall effect, and magnetoelectrical induction, theoretical and experimental studies of MAE measurement and conductivity reconstruction were performed. The formula of MAE voltage was derived and simplified for the transducer with strong directivity. MAE voltage was simulated for a three-layer gel phantom and the conductivity distribution was reconstructed using the modified Wiener inverse filter and Hilbert transform, which was also verified by experimental measurements. The experimental results are basically consistent with the simulations, and demonstrate that the wave packets of MAE voltage are generated at tissue interfaces with the amplitudes and vibration polarities representing the values and directions of conductivity variations. With the proposed algorithm, the amplitude and polarity of conductivity gradient can be restored and the conductivity distribution can also be reconstructed accurately. The favorable results demonstrate the feasibility of accurate conductivity reconstruction with improved spatial resolution using MAE measurement for tissues with conductivity variations, especially suitable for nondispersive tissues with abrupt conductivity changes. This study demonstrates that the MAE measurement based conductivity reconstruction algorithm can be applied as a new strategy for nondestructive real-time monitoring of conductivity variations in biomedical engineering.
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Teuwen, Christophe P; Kik, Charles; van der Does, Lisette J M E; Lanters, Eva A H; Knops, Paul; Mouws, Elisabeth M J P; Bogers, Ad J J C; de Groot, Natasja M S
2018-01-01
Atrial extrasystoles (AES) can initiate atrial fibrillation. However, the impact of spontaneous AES on intra-atrial conduction is unknown. The aims of this study were to examine conduction disorders provoked by AES and to correlate these conduction differences with patient characteristics, mapping locations, and type of AES. High-resolution epicardial mapping (electrodes N=128 or N=192; interelectrode distance, 2 mm) of the entire atrial surface was performed in patients (N=164; 69.5% male; age 67.2±10.5 years) undergoing open-chest cardiac surgery. AES were classified as premature, aberrant, or prematurely aberrant. Conduction delay and conduction block were quantified during sinus rhythm and AES and subsequently compared. Median incidence of conduction delay and conduction block during sinus rhythm was 1.2% (interquartile, 0%-2.3%) and 0.4% (interquartile, 0%-2.1%). In comparison, the median incidence of conduction delay and conduction block during 339 AES was respectively 2.8% (interquartile, 1.3%-4.6%) and 2.2% (interquartile, 0.3%-5.1%) and differed between the types of AES (prematurely aberrant>aberrant>premature). The degree of prematurity was not associated with a higher incidence of conduction disorders ( P >0.05). In contrast, a higher degree of aberrancy was associated with a higher incidence of conduction disorders; AES emerging as epicardial breakthrough provoked most conduction disorders ( P ≥0.002). AES caused most conduction disorders in patients with diabetes mellitus and left atrial dilatation ( P <0.05). Intraoperative high-resolution epicardial mapping showed that conduction disorders are mainly provoked by prematurely aberrant AES, particularly in patients with left atrial dilation and diabetes mellitus or emerging as epicardial breakthrough. © 2017 American Heart Association, Inc.
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NASA Astrophysics Data System (ADS)
Wu, Chia-Yu; Huang, Yin-Hsien; Wu, Hsin-Han; Hsieh, Tsung-Eong
2018-06-01
Fourier's law of heat conduction at steady-state was adopted to establish a measurement method utilizing platinum (Pt) thin-film electrodes as the heater and the temperature sensor. The thermal conductivities (κ's) of Pyrex glass, an epoxy resin and a commercial underfill for flip-chip devices were measured and a good agreement with previously reported values was obtained. The thermal boundary resistances (RTBR's) of Pt/sample interfaces were also extracted for discussing their influence on the thermal conduction of samples. Afterward, the flip-chip samples with 2×2 solder joint array utilizing Si wafers as the die and the substrate, without and with the underfills, were prepared and their thermal conductance were measured. For the sample without underfill, the air presenting in the gap of die and the substrate led to the poor thermal conductance of sample. With the insertion of underfills, the thermal conductance of flip-chip samples improved. The resistance to heat transfer across Si/underfill interfaces was also suppressed and to promote the thermal conductance of samples. The thermal properties of underfill and RTBR at Si/underfill interface were further implanted in the calculation of thermal conductance of flip-chip samples containing various solder joint arrays. The increasing number of solder joints diminished the influence of thermal conduction of underfill and RTBR of Si/underfill interface on the thermal conductance of samples. The insertion of underfill with high-κ value might promote the heat conductance of samples containing low-density solder joint arrays; however, it became insignificant in improving the heat conductance of samples containing high-density solder joint arrays.
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NASA Astrophysics Data System (ADS)
Cai, Jizhe; Naraghi, Mohammad
2016-08-01
In this work, a comprehensive multi-resolution two-dimensional (2D) resistor network model is proposed to analyze the electrical conductivity of hybrid nanomaterials made of insulating matrix with conductive particles such as CNT reinforced nanocomposites and thick film resistors. Unlike existing approaches, our model takes into account the impenetrability of the particles and their random placement within the matrix. Moreover, our model presents a detailed description of intra-particle conductivity via finite element analysis, which to the authors’ best knowledge has not been addressed before. The inter-particle conductivity is assumed to be primarily due to electron tunneling. The model is then used to predict the electrical conductivity of electrospun carbon nanofibers as a function of microstructural parameters such as turbostratic domain alignment and aspect ratio. To simulate the microstructure of single CNF, randomly positioned nucleation sites were seeded and grown as turbostratic particles with anisotropic growth rates. Particle growth was in steps and growth of each particle in each direction was stopped upon contact with other particles. The study points to the significant contribution of both intra-particle and inter-particle conductivity to the overall conductivity of hybrid composites. Influence of particle alignment and anisotropic growth rate ratio on electrical conductivity is also discussed. The results show that partial alignment in contrast to complete alignment can result in maximum electrical conductivity of whole CNF. High degrees of alignment can adversely affect conductivity by lowering the probability of the formation of a conductive path. The results demonstrate approaches to enhance electrical conductivity of hybrid materials through controlling their microstructure which is applicable not only to carbon nanofibers, but also many other types of hybrid composites such as thick film resistors.
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Optimization of Graphene Conductive Ink with 73 wt% Graphene Contents.
Xu, Chang-Yan; Shi, Xiao-Mei; Guo, Lu; Wang, Xi; Wang, Xin-Yi; Li, Jian-Yu
2018-06-01
With the pace of development accelerating in printed electronics, the fabrication and application of conductive ink have been brought into sharp focus in recent years. The discovery of graphene also unfolded a vigorous research campaign. In this paper, we prepared graphene conductive ink and explored the feasibility of applying the ink to flexible paper-based circuit. Since experimental study concentrating upon ink formulation was insufficient, orthogonal test design was used in the optimization of preparation formula of conductive ink for the first time. The purpose of this study was to determine the effect of constituent dosage on conductivity of graphene conductive ink, so as to obtain the optimized formula and prepare graphene conductive ink with good conductivity. Characterization of optimized graphene conductive ink we fabricated showed good adhesion to substrate and good resistance to acid and water. The graphene concentration of the optimized ink reached 73.17 wt% solid content. Particle size distribution of graphene conductive ink was uniform, which was about 1940 nm. Static surface tension was 28.9 mN/m and equilibrium contact angle was 23°, demonstrating that conductive ink had good wettability. Scanning Electron Microscope (SEM) analysis was also investigated, moreover, the feasibility of lightening a light-emitting diode (LED) light was verified. The graphene conductive ink with optimized formula can be stored for almost eight months, which had potential applications in flexible paper-based circuit in the future.
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Multielectronic conduction in La1-xSrxGa1/2Mn1/2O3-δ as solid oxide fuel cell cathode
NASA Astrophysics Data System (ADS)
Iguchi, E.; Hashimoto, Y.; Kurumada, M.; Munakata, F.
2003-08-01
Four-probe dc conductivities, capacitances, and thermopower have been measured in the temperature range of 80-1123 K for La1-xSrxGa1/2Mn1/2O3-δ, which is a desirable cathode material for lanthanum-gallate electrolytes of solid oxide fuel cells. The dc conductivities in the specimens (0.1⩽x⩽0.3) are insensitive to x but the thermopower is very sensitive to x, although the x=0 specimen exhibits a somewhat different conduction behavior. At T<300 K, a relaxation process has shown in dielectric loss factor with the activation energy higher than that for dc conduction in every specimen. These results at T<300 K have been numerically analyzed within the framework of the multielectronic conduction consisting of the polaronic conduction of Mn 3d eg holes created by Sr doping, the band conduction of O 2p holes and the hopping conduction of Mn 3d eg electrons, where the O 2p holes and Mn 3d eg electrons are created by thermal excitation of electrons from O 2p bands to Mn 3d eg narrow bands. At T>500 K, the band conduction dominates the electronic transports. The ionic conduction due to O2- migration seems difficult to contribute directly to the dc conduction even at high temperature.
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Undergraduate Conductors' and Conducting Teachers' Perceptions of Basic Conducting Efficacy
ERIC Educational Resources Information Center
Silvey, Brian A.; Baumgartner, Christopher M.
2016-01-01
The purpose of this study was to examine undergraduate conductors' and conducting teachers' perceptions about basic conducting efficacy. At the beginning and end of the semester, undergraduate students (N = 19) enrolled in a basic conducting course (a) were surveyed about the importance of certain skills necessary for being an effective conductor…
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Code of Federal Regulations, 2011 CFR
2011-10-01
... 45 Public Welfare 3 2011-10-01 2011-10-01 false Cross-references to employee ethical conduct... EMPLOYEE RESPONSIBILITIES AND CONDUCT § 706.1 Cross-references to employee ethical conduct standards... States Commission on Civil Rights are subject to the executive branch standards of ethical conduct...
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49 CFR 99.735-1 - Cross-reference to ethical conduct standards and financial disclosure regulations.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 1 2011-10-01 2011-10-01 false Cross-reference to ethical conduct standards and... Transportation EMPLOYEE RESPONSIBILITIES AND CONDUCT General § 99.735-1 Cross-reference to ethical conduct... the executive branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Department of...
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Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 4 2011-01-01 2011-01-01 false Cross-references to employee ethical conduct standards... Cross-references to employee ethical conduct standards, financial disclosure regulations, and other conduct rules. Employees of DOE are subject to the Standards of Ethical Conduct for Employees of the...
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40 CFR 792.130 - Conduct of a study.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Conduct of a study. 792.130 Section... ACT (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems...
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Code of Federal Regulations, 2010 CFR
2010-10-01
... 45 Public Welfare 3 2010-10-01 2010-10-01 false Cross-references to employee ethical conduct... EMPLOYEE RESPONSIBILITIES AND CONDUCT § 706.1 Cross-references to employee ethical conduct standards... States Commission on Civil Rights are subject to the executive branch standards of ethical conduct...
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49 CFR 99.735-1 - Cross-reference to ethical conduct standards and financial disclosure regulations.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 1 2010-10-01 2010-10-01 false Cross-reference to ethical conduct standards and... Transportation EMPLOYEE RESPONSIBILITIES AND CONDUCT General § 99.735-1 Cross-reference to ethical conduct... the executive branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Department of...
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Code of Federal Regulations, 2010 CFR
2010-07-01
... employee ethical conduct standards, financial disclosure regulations, and other regulations. 105-735.1... CONDUCT § 105-735.1 Cross-references to employee ethical conduct standards, financial disclosure... executive branch-wide standards of ethical conduct at 5 CFR part 2635, GSA's regulations at 5 CFR part 6701...
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Electrically-Conductive Polyaramid Cable And Fabric
NASA Technical Reports Server (NTRS)
Orban, Ralph F.
1988-01-01
Tows coated with metal provide strength and conductance. Cable suitable for use underwater made of electrically conductive tows of metal-coated polyaramid filaments surrounded by electrically insulating jacket. Conductive tows used to make conductive fabrics. Tension borne by metal-coated filaments, so upon release, entire cable springs back to nearly original length without damage.
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Code of Federal Regulations, 2014 CFR
2014-07-01
... employee ethical and other conduct standards and financial disclosure regulations. 0.735-10 Section 0.735... ETHICAL CONDUCT, AND RELATED RESPONSIBILITIES Standards of Ethical Conduct and Related Responsibilities of Employees § 0.735-10 Cross-reference to employee ethical and other conduct standards and financial...
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49 CFR 99.735-1 - Cross-reference to ethical conduct standards and financial disclosure regulations.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 1 2013-10-01 2013-10-01 false Cross-reference to ethical conduct standards and... Transportation EMPLOYEE RESPONSIBILITIES AND CONDUCT General § 99.735-1 Cross-reference to ethical conduct... the executive branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Department of...
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Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 4 2013-01-01 2013-01-01 false Cross-references to employee ethical conduct standards... Cross-references to employee ethical conduct standards, financial disclosure regulations, and other conduct rules. Employees of DOE are subject to the Standards of Ethical Conduct for Employees of the...
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Code of Federal Regulations, 2013 CFR
2013-07-01
... employee ethical and other conduct standards and financial disclosure regulations. 0.735-10 Section 0.735... ETHICAL CONDUCT, AND RELATED RESPONSIBILITIES Standards of Ethical Conduct and Related Responsibilities of Employees § 0.735-10 Cross-reference to employee ethical and other conduct standards and financial...
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Code of Federal Regulations, 2012 CFR
2012-10-01
... 45 Public Welfare 3 2012-10-01 2012-10-01 false Cross-references to employee ethical conduct... EMPLOYEE RESPONSIBILITIES AND CONDUCT § 706.1 Cross-references to employee ethical conduct standards... States Commission on Civil Rights are subject to the executive branch standards of ethical conduct...
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49 CFR 99.735-1 - Cross-reference to ethical conduct standards and financial disclosure regulations.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 1 2014-10-01 2014-10-01 false Cross-reference to ethical conduct standards and... Transportation EMPLOYEE RESPONSIBILITIES AND CONDUCT General § 99.735-1 Cross-reference to ethical conduct... the executive branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Department of...
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Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 4 2012-01-01 2012-01-01 false Cross-references to employee ethical conduct standards... Cross-references to employee ethical conduct standards, financial disclosure regulations, and other conduct rules. Employees of DOE are subject to the Standards of Ethical Conduct for Employees of the...
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Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 4 2014-01-01 2014-01-01 false Cross-references to employee ethical conduct standards... Cross-references to employee ethical conduct standards, financial disclosure regulations, and other conduct rules. Employees of DOE are subject to the Standards of Ethical Conduct for Employees of the...
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Code of Federal Regulations, 2013 CFR
2013-10-01
... 45 Public Welfare 3 2013-10-01 2013-10-01 false Cross-references to employee ethical conduct... EMPLOYEE RESPONSIBILITIES AND CONDUCT § 706.1 Cross-references to employee ethical conduct standards... States Commission on Civil Rights are subject to the executive branch standards of ethical conduct...
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Code of Federal Regulations, 2014 CFR
2014-10-01
... 45 Public Welfare 3 2014-10-01 2014-10-01 false Cross-references to employee ethical conduct... EMPLOYEE RESPONSIBILITIES AND CONDUCT § 706.1 Cross-references to employee ethical conduct standards... States Commission on Civil Rights are subject to the executive branch standards of ethical conduct...
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49 CFR 99.735-1 - Cross-reference to ethical conduct standards and financial disclosure regulations.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 1 2012-10-01 2012-10-01 false Cross-reference to ethical conduct standards and... Transportation EMPLOYEE RESPONSIBILITIES AND CONDUCT General § 99.735-1 Cross-reference to ethical conduct... the executive branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Department of...
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28 CFR 523.20 - Good conduct time.
Code of Federal Regulations, 2011 CFR
2011-07-01
... TRANSFER COMPUTATION OF SENTENCE Good Conduct Time § 523.20 Good conduct time. (a) For inmates serving a... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Good conduct time. 523.20 Section 523.20... will award 54 days credit toward service of sentence (good conduct time credit) for each year served...
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28 CFR 523.20 - Good conduct time.
Code of Federal Regulations, 2013 CFR
2013-07-01
... TRANSFER COMPUTATION OF SENTENCE Good Conduct Time § 523.20 Good conduct time. (a) For inmates serving a... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Good conduct time. 523.20 Section 523.20... will award 54 days credit toward service of sentence (good conduct time credit) for each year served...
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28 CFR 523.20 - Good conduct time.
Code of Federal Regulations, 2012 CFR
2012-07-01
... TRANSFER COMPUTATION OF SENTENCE Good Conduct Time § 523.20 Good conduct time. (a) For inmates serving a... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Good conduct time. 523.20 Section 523.20... will award 54 days credit toward service of sentence (good conduct time credit) for each year served...
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28 CFR 523.20 - Good conduct time.
Code of Federal Regulations, 2014 CFR
2014-07-01
... TRANSFER COMPUTATION OF SENTENCE Good Conduct Time § 523.20 Good conduct time. (a) For inmates serving a... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Good conduct time. 523.20 Section 523.20... will award 54 days credit toward service of sentence (good conduct time credit) for each year served...
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Lv, Y; Cui, J; Jiang, Z M; Yang, X J
2013-02-15
Atomic force microscopy imaging combined with selective chemical etching is employed to quantitatively investigate three-dimensional (3D) composition distributions of single GeSi quantum rings (QRs). In addition, the 3D quantitative composition distributions and the corresponding conductance distributions are simultaneously obtained on the same single GeSi QRs by conductive atomic force microscopy combined with selective chemical etching, allowing us to investigate the correlations between the conductance and composition distributions of single QRs. The results show that the QRs' central holes have higher Ge content, but exhibit lower conductance, indicating that the QRs' conductance distribution is not consistent with their composition distribution. By comparing the topography, composition and conductance profiles of the same single QRs before and after different etching processes, it is found that the conductance distributions of GeSi QRs do not vary with the change of composition distribution. Instead, the QRs' conductance distributions are found to be consistent with their topographic shapes, which can be supposed to be due to the shape determined electronic structures.
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Scaling relation of the anomalous Hall effect in (Ga,Mn)As
NASA Astrophysics Data System (ADS)
Glunk, M.; Daeubler, J.; Schoch, W.; Sauer, R.; Limmer, W.
2009-09-01
We present magnetotransport studies performed on an extended set of (Ga,Mn)As samples at 4.2 K with longitudinal conductivities σxx ranging from the low-conductivity to the high-conductivity regime. The anomalous Hall conductivity σxy(AH) is extracted from the measured longitudinal and Hall resistivities. A transition from σxy(AH)=20Ω-1cm-1 due to the Berry phase effect in the high-conductivity regime to a scaling relation σxy(AH)∝σxx1.6 for low-conductivity samples is observed. This scaling relation is consistent with a recently developed unified theory of the anomalous Hall effect in the framework of the Keldysh formalism. It turns out to be independent of crystallographic orientation, growth conditions, Mn concentration, and strain, and can therefore be considered universal for low-conductivity (Ga,Mn)As. The relation plays a crucial role when deriving values of the hole concentration from magnetotransport measurements in low-conductivity (Ga,Mn)As. In addition, the hole diffusion constants for the high-conductivity samples are determined from the measured longitudinal conductivities.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Cho, Hyun Woo; Kim, Jeongmin; Sung, Bong June, E-mail: jjpark@chonnam.ac.kr, E-mail: bjsung@sogang.ac.kr
We investigate how the electrical conductance of microfibers (made of polymers and conductive nanofillers) decreases upon uniaxial deformation by performing both experiments and simulations. Even though various elastic conductors have been developed due to promising applications for deformable electronic devices, the mechanism at a molecular level for electrical conductance change has remained elusive. Previous studies proposed that the decrease in electrical conductance would result from changes in either distances or contact numbers between conductive fillers. In this work, we prepare microfibers of single walled carbon nanotubes (SWCNTs)/polyvinyl alcohol composites and investigate the electrical conductance and the orientation of SWCNTs uponmore » uniaxial deformation. We also perform extensive Monte Carlo simulations, which reproduce experimental results for the relative decrease in conductance and the SWCNTs orientation. We investigate the electrical networks of SWCNTs in microfibers and find that the decrease in the electrical conductance upon uniaxial deformation should be attributed to a subtle change in the topological structure of the electrical network.« less
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The optimal structure-conductivity relation in epoxy-phthalocyanine nanocomposites.
Huijbregts, L J; Brom, H B; Brokken-Zijp, J C M; Kemerink, M; Chen, Z; Goeje, M P de; Yuan, M; Michels, M A J
2006-11-23
Phthalcon-11 (aquocyanophthalocyaninatocobalt (III)) forms semiconducting nanocrystals that can be dispersed in epoxy coatings to obtain a semiconducting material with a low percolation threshold. We investigated the structure-conductivity relation in this composite and the deviation from its optimal realization by combining two techniques. The real parts of the electrical conductivity of a Phthalcon-11/epoxy coating and of Phthalcon-11 powder were measured by dielectric spectroscopy as a function of frequency and temperature. Conducting atomic force microscopy (C-AFM) was applied to quantify the conductivity through the coating locally along the surface. This combination gives an excellent tool to visualize the particle network. We found that a large fraction of the crystals is organized in conducting channels of fractal building blocks. In this picture, a low percolation threshold automatically leads to a conductivity that is much lower than that of the filler. Since the structure-conductivity relation for the found network is almost optimal, a drastic increase in the conductivity of the coating cannot be achieved by changing the particle network, but only by using a filler with a higher conductivity level.
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Kazemzadeh, Mohammad-Rahim; Alighanbari, Abbas
2018-04-16
A three-dimensional transformation optics method, leading to homogeneous materials, applicable to any non-Cartesian coordinate systems or waveguides/objects of arbitrary cross-sections is presented. Both the conductive boundary and internal material of the desired device is determined by the proposed formulation. The method is applicable to a wide range of waveguide, radiation, and cloaking problems, and is demonstrated for circular waveguide couplers and an external cloak. An advantage of the present method is that the material properties are simplified by appropriately selecting the conductive boundaries. For instance, a right-angle circular waveguide bend is presented which uses only one homogenous material. Also, transformation of conductive materials and boundaries are studied. The conditions in which the transformed boundaries remain conductive are discussed. In addition, it is demonstrated that negative infinite conductivity can be replaced with positive conductivity, without affecting the field outside the conductive boundary. It is also observed that a negative finite conductivity can be replaced with a positive one, by accepting some small errors. The general mathematical procedure and formulation for calculating the parametric surface equations of the conductive peripheries are presented.
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Regulation of Conduction Time along Axons
Seidl, Armin H.
2013-01-01
Timely delivery of information is essential for proper function of the nervous system. Precise regulation of nerve conduction velocity is needed for correct exertion of motor skills, sensory integration and cognitive functions. In vertebrates, the rapid transmission of signals along nerve fibers is made possible by the myelination of axons and the resulting saltatory conduction in between nodes of Ranvier. Myelin is a specialization of glia cells and is provided by oligodendrocytes in the central nervous system. Myelination not only maximizes conduction velocity, but also provides a means to systematically regulate conduction times in the nervous system. Systematic regulation of conduction velocity along axons, and thus systematic regulation of conduction time in between neural areas, is a common occurrence in the nervous system. To date, little is understood about the mechanism that underlies systematic conduction velocity regulation and conduction time synchrony. Node assembly, internode distance (node spacing) and axon diameter - all parameters determining the speed of signal propagation along axons - are controlled by myelinating glia. Therefore, an interaction between glial cells and neurons has been suggested. This review summarizes examples of neural systems in which conduction velocity is regulated by anatomical variations along axons. While functional implications in these systems are not always clear, recent studies in the auditory system of birds and mammals present examples of conduction velocity regulation in systems with high temporal precision and a defined biological function. Together these findings suggest an active process that shapes the interaction between axons and myelinating glia to control conduction velocity along axons. Future studies involving these systems may provide further insight into how specific conduction times in the brain are established and maintained in development. Throughout the text, conduction velocity is used for the speed of signal propagation, i.e. the speed at which an action potential travels. Conduction time refers to the time it takes for a specific signal to travel from its origin to its target, i.e. neuronal cell body to axonal terminal. PMID:23820043
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NASA Astrophysics Data System (ADS)
Mandolesi, E.; Moorkamp, M.; Jones, A. G.
2014-12-01
Most electromagnetic (EM) geophysical methods focus on the electrical conductivity of rocks and sediments to determine the geological structure of the subsurface. Electric conductivity itself is measured in the laboratory with a wide range of instruments and techniques. These measurements seldom return a compatible result. The presence of partially-interconnected random pathways of electrically conductive materials in resistive hosts has been studied for decades, and recently with increasing interest. To comprehend which conductive mechanism scales from the microstructures up to field electrical conductivity measurements, two main branch of studies have been undertaken: statistical probability of having a conductive pathways and mixing laws. Several numerical approaches have been tested to understand the effects of interconnected pathways of conductors at field scale. Usually these studies were restricted in two ways: the sources are considered constant in time (i.e., DC) and the domain is, with few exception, two-dimensional. We simulated the effects of time-varying EM sources on the conductivity measured on the surface of a three-dimensional randomly generated body embedded in an uniform host by using electromagnetic induction equations. We modelled a two-phase mixture of resistive and conductive elements with the goal of comparing the conductivity measured on field scale with the one proper of the elements constituting the random rock, and to test how the internal structures influence the directionality of the responses. Moreover, we modelled data from randomly generated bodies characterized by coherent internal structures, to check the effect of the named structures on the anisotropy of the effective conductivity. We compared these values with the electrical conductivity limits predicted by Hashin-Shtrikman bounds and the effective conductivity predicted by the Archie's law, both cast in its classic form and in an updated that allow to take in account two materials. The same analysis was done for both the resistive and the conductive conductivity values for the anisotropic case.
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Conduction quantization in monolayer MoS2
NASA Astrophysics Data System (ADS)
Li, T. S.
2016-10-01
We study the ballistic conduction of a monolayer MoS2 subject to a spatially modulated magnetic field by using the Landauer-Buttiker formalism. The band structure depends sensitively on the field strength, and its change has profound influence on the electron conduction. The conductance is found to demonstrate multi-step behavior due to the discrete number of conduction channels. The sharp peak and rectangular structures of the conductance are stretched out as temperature increases, due to the thermal broadening of the derivative of the Fermi-Dirac distribution function. Finally, quantum behavior in the conductance of MoS2 can be observed at temperatures below 10 K.
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NASA Technical Reports Server (NTRS)
Manohara, Harish (Inventor); Del Castillo, Linda Y. (Inventor); Mojarradi, Mohammed M. (Inventor)
2016-01-01
Systems and methods in accordance with embodiments of the invention implement micro- and nanoscale capacitors that incorporate a conductive element that conforms to the shape of an array elongated bodies. In one embodiment, a capacitor that incorporates a conductive element that conforms to the shape of an array of elongated bodies includes: a first conductive element that conforms to the shape of an array of elongated bodies; a second conductive element that conforms to the shape of an array of elongated bodies; and a dielectric material disposed in between the first conductive element and the second conductive element, and thereby physically separates them.
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Investigation of the technology of conductive yarns manufacturing
NASA Astrophysics Data System (ADS)
Ryklin, Dzmitry; Medvetski, Sergey
2017-10-01
The paper is devoted to development of technology of electrically conductive yarn production. This technology allows manufacturing conductive yarns of copper wire and polyester filament yarns. Method of the predicting of the conductive yarn breaking force was developed on the base of analysing of load-elongation curves of each strand of the yarn. Also the method of the predicting of the conductive yarn diameter was offered. Investigation shows that conductive yarns can be integrated into the textiles structure using sewing or embroidery equipment. Application of developed conductive yarn is wearable electronics creating with wide range of functions, for example, for specific health issue monitoring, navigation tools or communication gadgets.
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Conductivity Enhancement of PEDOT:PSS Films Through the Surface Treatment with Organic Solvent.
Lee, Sungkoo
2016-03-01
The improvement of conductivity is a key factor in application of conducting polymer to elec- tronic devices. The conductivity enhancement of PSS films were observed after dipping in polar organic solvents, including DMSO, ethylene glycol, glycerol and IPA. The conductivity of PSS films increased from 0.5 S/cm to over 800 S/cm, that is, by a factor of more than 1,600. The conductivity enhancement was dependent on the type of organic solvents and dipping time of PSS into solvent. The enhancement of conductivity may be caused by the phase separation between PEDOT chains and PSS counter anions.
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The role of mesophyll conductance in the economics of nitrogen and water use in photosynthesis.
Buckley, Thomas N; Warren, Charles R
2014-02-01
A recent resurgence of interest in formal optimisation theory has begun to improve our understanding of how variations in stomatal conductance and photosynthetic capacity control the response of whole plant photosynthesis and growth to the environment. However, mesophyll conductance exhibits similar variation and has similar impact on photosynthesis as stomatal conductance; yet, the role of mesophyll conductance in the economics of photosynthetic resource use has not been thoroughly explored. In this article, we first briefly summarise the knowledge of how mesophyll conductance varies in relation to environmental factors that also affect stomatal conductance and photosynthetic capacity, and then we use a simple analytical approach to begin to explore how these important controls on photosynthesis should mutually co-vary in a plant canopy in the optimum. Our analysis predicts that when either stomatal or mesophyll conductance is limited by fundamental biophysical constraints in some areas of a canopy, e.g. reduced stomatal conductance in upper canopy leaves due to reduced water potential, the other of the two conductances should increase in those leaves, while photosynthetic capacity should decrease. Our analysis also predicts that if mesophyll conductance depends on nitrogen investment in one or more proteins, then nitrogen investment should shift away from Rubisco and towards mesophyll conductance if hydraulic or other constraints cause chloroplastic CO2 concentration to decline. Thorough exploration of these issues awaits better knowledge of whether and how mesophyll conductance is itself limited by nitrogen investment, and about how these determinants of photosynthetic CO2 supply and demand co-vary among leaves in real plant canopies.
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Hong, Ji S; Tillman, Rebecca; Luby, Joan L
2015-03-01
To investigate which disruptive behaviors in preschool were normative and transient vs markers of conduct disorder, as well as which disruptive behaviors predicted the persistence of conduct disorder into school age. Data from a longitudinal study of preschool children were used to investigate disruptive behaviors. Caregivers of preschoolers ages 3.0-5.11 years (n = 273) were interviewed using the Preschool Age Psychiatric Assessment to derive the following diagnostic groups: conduct disorder, externalizing disorder without conduct disorder, internalizing disorder without externalizing disorder, and healthy. At school age, participants were again assessed via an age-appropriate diagnostic interview. Logistic and linear regression with pairwise group comparisons was used to investigate clinical markers of preschool conduct disorder and predictors of school age conduct disorder. Losing one's temper, low-intensity destruction of property, and low-intensity deceitfulness/stealing in the preschool period were found in both healthy and disordered groups. In contrast, high-intensity argument/defiant behavior, both low- and high-intensity aggression to people/animals, high-intensity destruction of property, high-intensity deceitfulness/stealing, and high-intensity peer problems were markers of preschool conduct disorder and predictors of school age conduct disorder. Inappropriate sexual behavior was not a marker for preschool conduct disorder but was a predictor of school age conduct disorder. These findings provide a guide for primary care clinicians to help identify preschoolers with clinical conduct disorder and those who are at risk for persistent conduct disorder in childhood. Preschoolers displaying these symptoms should be targeted for mental health assessment. Copyright © 2015 Elsevier Inc. All rights reserved.
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Corneal iron ring after conductive keratoplasty.
Kymionis, George D; Naoumidi, Tatiana L; Aslanides, Ioannis M; Pallikaris, Ioannis G
2003-08-01
To report formation of corneal iron ring deposits after conductive keratoplasty. Observational case report. Case report. A 54-year-old woman underwent conductive keratoplasty for hyperopia. One year after conductive keratoplasty, iron ring pattern pigmentation was detected at the corneal epithelium of both eyes. This is the first report of the appearance of corneal iron ring deposits following conductive keratoplasty treatment in a patient. It is suggested that alterations in tear film stability, resulting from conductive keratoplasty-induced changes in corneal curvature, constitute the contributory factor for these deposits.
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2014-09-01
with approximately 5 × 1018 Si atoms/cm3 to yield a conductive buffer for STM and photoemsission spectroscopy measurements. On some samples a 3 nm ErAs...where S is the Seebeck coefficient, σ is the electrical conductivity , and κ is the thermal conductivity . Here the electronic information is contained... conductivities (κ = κe + κlat). While the electronic component of thermal conductivity κe is inherently tied to electrical conductivity σ via Wiedemann
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Synthesis of Conductive Polymeric Nanocomposites for Applications in Responsive Materials
NASA Astrophysics Data System (ADS)
Chavez, Jessica
The development of next generation "smart" textiles has emerged with significant interest due to the immense demand for high-performance wearable technology. The economic market for wearable technologies is predicted to increase significantly in both volume and value. In the next four years, the wearable technology market will be valued at $34 billion. This large demand has opened up a new research area involving smart wearable devices and conductive fabrics. Many research groups have taken various paths to study and ultimately fabricate wearable devices. Due to the limiting capabilities of conventional conductors, researchers have centered their research on the integration of conductive polymers into textile materials for applications involving responsive material. Conducive polymers are very unique organic molecules that have the ability to transfer electrons across their molecular structure due to the excess presence of pi-electrons. Conductive polymers are favored over conventional conductors because they can be easily manipulated and integrated into flexible material. Two very common conductive polymers are polyaniline (PANI) and polypyrrole (PPY) because of their large favorability in literature, high conductance values, and environmental stability. Common commercial fibers were coated via the chemical polymerization of PANI or PPY. A series of reactions were done to study the polymerization process of each polymer. The conductive efficiency of each conducting polymer is highly dependent on the type of reactants used, the acidic nature of the reaction, and the temperature of the reaction. The coated commercial fiber nanocomposites produced higher conductivity values when the polymerization reaction was run using ammonium peroxydisulfate (APS) as the oxidizing agent, run in an acidic environment, and run at very low temperatures. Other factors that improved the overall efficiency of the coated commercial fiber nanocomposites was the increase in polymer concentration as well as the extension of the reaction time. The overall interaction between the conductive polymer and the commercial fibers showed that the conductive polymer was physically adsorbed to the commercial fiber. This physical adsorption caused a decrease in conductive efficiency as a function of repeated washes because the weak intermolecular forces between the conductive polymer and the commercial fiber. This led to the synthesis of conductive films and nanofibers by integrating the conductive polymers directly into a cellulose acetate matrix. The voltage efficiency of the conductive films was lower compared to the coated commercial fiber nanocomposites. However, the conductive material generated greater lux values compared to the coated commercial fiber nanocomposites. Theses conductive materials can be applied to applications in both the medical field and water filtration. The conductive films can be used to create a sensor based system that can trigger a sensor to signify when bandages used for wound management need to be changed. The conductive nanofibers can be used in water filtration as a means of electroplating metals ions from contaminated water. Overall, the synthesis of these conductive materials can be applicable for responsive materials.
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Code of Federal Regulations, 2011 CFR
2011-01-01
... 12 Banks and Banking 4 2011-01-01 2011-01-01 false Cross-reference to employee ethical conduct... and Conduct § 336.1 Cross-reference to employee ethical conduct standards and financial disclosure... Branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Corporation regulation at 5 CFR part...
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Code of Federal Regulations, 2011 CFR
2011-07-01
... 34 Education 1 2011-07-01 2011-07-01 false Cross-reference to employee ethical conduct standards... of Education STANDARDS OF CONDUCT § 73.1 Cross-reference to employee ethical conduct standards and... branch-wide Standards of Ethical Conduct at 5 CFR part 2635 and to the Department of Education regulation...
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Code of Federal Regulations, 2011 CFR
2011-04-01
... employee ethical conduct standards and financial disclosure regulations. 3c.1 Section 3c.1 Conservation of... STANDARDS OF CONDUCT § 3c.1 Cross-reference to employee ethical conduct standards and financial disclosure... branch-wide financial disclosure regulations at 5 CFR part 2634, the Standards of Ethical Conduct for...
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Code of Federal Regulations, 2011 CFR
2011-04-01
... 22 Foreign Relations 2 2011-04-01 2009-04-01 true Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1001.1 Cross-references to employee ethical conduct... Foundation should refer to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...
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Code of Federal Regulations, 2011 CFR
2011-01-01
... ethical conduct standards and financial disclosure regulations. 105.101 Section 105.101 Business Credit... RESPONSIBILITIES Standards of Conduct § 105.101 Cross-reference to employee ethical conduct standards and financial... to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR part 2635 and the...
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Code of Federal Regulations, 2011 CFR
2011-04-01
... 22 Foreign Relations 2 2011-04-01 2009-04-01 true Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1504.1 Cross-references to employee ethical conduct... Foundation are subject to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...
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40 CFR 792.130 - Conduct of a study.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Conduct of a study. 792.130 Section 792... (CONTINUED) GOOD LABORATORY PRACTICE STANDARDS Protocol for and Conduct of A Study § 792.130 Conduct of a study. (a) The study shall be conducted in accordance with the protocol. (b) The test systems shall be...
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36 CFR § 702.2 - Conduct on Library premises.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Conduct on Library premises. § 702.2 Section § 702.2 Parks, Forests, and Public Property LIBRARY OF CONGRESS CONDUCT ON LIBRARY PREMISES § 702.2 Conduct on Library premises. (a) All persons using the premises shall conduct themselves...
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Code of Federal Regulations, 2010 CFR
2010-07-01
... 34 Education 1 2010-07-01 2010-07-01 false Cross-reference to employee ethical conduct standards... of Education STANDARDS OF CONDUCT § 73.1 Cross-reference to employee ethical conduct standards and... branch-wide Standards of Ethical Conduct at 5 CFR part 2635 and to the Department of Education regulation...
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Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Cross-references to employee ethical conduct standards... ENERGY (GENERAL PROVISIONS) CONDUCT OF EMPLOYEES § 1010.102 Cross-references to employee ethical conduct... Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR part 2635, the DOE regulation at...
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Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Cross-reference to employee ethical conduct... and Conduct § 336.1 Cross-reference to employee ethical conduct standards and financial disclosure... Branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Corporation regulation at 5 CFR part...
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Code of Federal Regulations, 2010 CFR
2010-01-01
... ethical conduct standards and financial disclosure regulations. 105.101 Section 105.101 Business Credit... RESPONSIBILITIES Standards of Conduct § 105.101 Cross-reference to employee ethical conduct standards and financial... to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR part 2635 and the...
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Code of Federal Regulations, 2010 CFR
2010-04-01
... employee ethical conduct standards and financial disclosure regulations. 3c.1 Section 3c.1 Conservation of... STANDARDS OF CONDUCT § 3c.1 Cross-reference to employee ethical conduct standards and financial disclosure... branch-wide financial disclosure regulations at 5 CFR part 2634, the Standards of Ethical Conduct for...
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Code of Federal Regulations, 2010 CFR
2010-04-01
... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1001.1 Cross-references to employee ethical conduct... Foundation should refer to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...
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Code of Federal Regulations, 2010 CFR
2010-04-01
... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1504.1 Cross-references to employee ethical conduct... Foundation are subject to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...
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29 CFR 1400.735-20 - Code of Professional Conduct for Labor Mediators.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 29 Labor 4 2010-07-01 2010-07-01 false Code of Professional Conduct for Labor Mediators. 1400.735... Conduct and Responsibilities § 1400.735-20 Code of Professional Conduct for Labor Mediators. In 1964, a Code of Professional Conduct for Labor Mediators was drafted by a Federal-State Liaison Committee and...
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Code of Federal Regulations, 2012 CFR
2012-01-01
... 12 Banks and Banking 4 2012-01-01 2012-01-01 false Cross-reference to employees' ethical conduct... AND CONDUCT § 264.101 Cross-reference to employees' ethical conduct standards and financial disclosure... executive branch-wide standards of ethical conduct at 5 CFR part 2635 and the Board's regulation at 5 CFR...
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Code of Federal Regulations, 2014 CFR
2014-04-01
... 22 Foreign Relations 2 2014-04-01 2014-04-01 false Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1504.1 Cross-references to employee ethical conduct... Foundation are subject to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...
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Code of Federal Regulations, 2014 CFR
2014-01-01
... 12 Banks and Banking 4 2014-01-01 2014-01-01 false Cross-reference to employees' ethical conduct... AND CONDUCT § 264.101 Cross-reference to employees' ethical conduct standards and financial disclosure... executive branch-wide standards of ethical conduct at 5 CFR part 2635 and the Board's regulation at 5 CFR...
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Code of Federal Regulations, 2014 CFR
2014-04-01
... 22 Foreign Relations 2 2014-04-01 2014-04-01 false Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1001.1 Cross-references to employee ethical conduct... Foundation should refer to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...
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Code of Federal Regulations, 2014 CFR
2014-01-01
... 12 Banks and Banking 5 2014-01-01 2014-01-01 false Cross-reference to employee ethical conduct... and Conduct § 336.1 Cross-reference to employee ethical conduct standards and financial disclosure... Branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Corporation regulation at 5 CFR part...
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Code of Federal Regulations, 2014 CFR
2014-04-01
... employee ethical conduct standards and financial disclosure regulations. 3c.1 Section 3c.1 Conservation of... STANDARDS OF CONDUCT § 3c.1 Cross-reference to employee ethical conduct standards and financial disclosure... branch-wide financial disclosure regulations at 5 CFR part 2634, the Standards of Ethical Conduct for...
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Code of Federal Regulations, 2013 CFR
2013-04-01
... 22 Foreign Relations 2 2013-04-01 2009-04-01 true Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1504.1 Cross-references to employee ethical conduct... Foundation are subject to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...
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Code of Federal Regulations, 2013 CFR
2013-04-01
... 22 Foreign Relations 2 2013-04-01 2009-04-01 true Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1001.1 Cross-references to employee ethical conduct... Foundation should refer to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...
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Code of Federal Regulations, 2013 CFR
2013-04-01
... employee ethical conduct standards and financial disclosure regulations. 3c.1 Section 3c.1 Conservation of... STANDARDS OF CONDUCT § 3c.1 Cross-reference to employee ethical conduct standards and financial disclosure... branch-wide financial disclosure regulations at 5 CFR part 2634, the Standards of Ethical Conduct for...
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Code of Federal Regulations, 2012 CFR
2012-04-01
... 22 Foreign Relations 2 2012-04-01 2009-04-01 true Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1001.1 Cross-references to employee ethical conduct... Foundation should refer to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...
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Code of Federal Regulations, 2014 CFR
2014-07-01
... 34 Education 1 2014-07-01 2014-07-01 false Cross-reference to employee ethical conduct standards... of Education STANDARDS OF CONDUCT § 73.1 Cross-reference to employee ethical conduct standards and... branch-wide Standards of Ethical Conduct at 5 CFR part 2635 and to the Department of Education regulation...
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Code of Federal Regulations, 2013 CFR
2013-01-01
... 12 Banks and Banking 5 2013-01-01 2013-01-01 false Cross-reference to employee ethical conduct... and Conduct § 336.1 Cross-reference to employee ethical conduct standards and financial disclosure... Branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Corporation regulation at 5 CFR part...
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Code of Federal Regulations, 2012 CFR
2012-01-01
... 12 Banks and Banking 5 2012-01-01 2012-01-01 false Cross-reference to employee ethical conduct... and Conduct § 336.1 Cross-reference to employee ethical conduct standards and financial disclosure... Branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Corporation regulation at 5 CFR part...
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Code of Federal Regulations, 2012 CFR
2012-04-01
... 22 Foreign Relations 2 2012-04-01 2009-04-01 true Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1504.1 Cross-references to employee ethical conduct... Foundation are subject to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...
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Code of Federal Regulations, 2013 CFR
2013-07-01
... 34 Education 1 2013-07-01 2013-07-01 false Cross-reference to employee ethical conduct standards... of Education STANDARDS OF CONDUCT § 73.1 Cross-reference to employee ethical conduct standards and... branch-wide Standards of Ethical Conduct at 5 CFR part 2635 and to the Department of Education regulation...
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Code of Federal Regulations, 2013 CFR
2013-01-01
... 12 Banks and Banking 4 2013-01-01 2013-01-01 false Cross-reference to employees' ethical conduct... AND CONDUCT § 264.101 Cross-reference to employees' ethical conduct standards and financial disclosure... executive branch-wide standards of ethical conduct at 5 CFR part 2635 and the Board's regulation at 5 CFR...
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Code of Federal Regulations, 2012 CFR
2012-04-01
... employee ethical conduct standards and financial disclosure regulations. 3c.1 Section 3c.1 Conservation of... STANDARDS OF CONDUCT § 3c.1 Cross-reference to employee ethical conduct standards and financial disclosure... branch-wide financial disclosure regulations at 5 CFR part 2634, the Standards of Ethical Conduct for...
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Code of Federal Regulations, 2014 CFR
2014-01-01
... ethical conduct standards and financial disclosure regulations. 105.101 Section 105.101 Business Credit... RESPONSIBILITIES Standards of Conduct § 105.101 Cross-reference to employee ethical conduct standards and financial... to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR part 2635 and the...
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Code of Federal Regulations, 2012 CFR
2012-01-01
... ethical conduct standards and financial disclosure regulations. 105.101 Section 105.101 Business Credit... RESPONSIBILITIES Standards of Conduct § 105.101 Cross-reference to employee ethical conduct standards and financial... to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR part 2635 and the...
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Code of Federal Regulations, 2012 CFR
2012-07-01
... 34 Education 1 2012-07-01 2012-07-01 false Cross-reference to employee ethical conduct standards... of Education STANDARDS OF CONDUCT § 73.1 Cross-reference to employee ethical conduct standards and... branch-wide Standards of Ethical Conduct at 5 CFR part 2635 and to the Department of Education regulation...
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Code of Federal Regulations, 2013 CFR
2013-01-01
... ethical conduct standards and financial disclosure regulations. 105.101 Section 105.101 Business Credit... RESPONSIBILITIES Standards of Conduct § 105.101 Cross-reference to employee ethical conduct standards and financial... to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR part 2635 and the...
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Naseri, Maryam; Fotouhi, Lida; Ehsani, Ali
2018-06-01
Among various immobilizing materials, conductive polymer-based nanocomposites have been widely applied to fabricate the biosensors, because of their outstanding properties such as excellent electrocatalytic activity, high conductivity, and strong adsorptive ability compared to conventional conductive polymers. Electrochemical biosensors have played a significant role in delivering the diagnostic information and therapy monitoring in a rapid, simple, and low cost portable device. This paper reviews the recent developments in conductive polymer-based nanocomposites and their applications in electrochemical biosensors. The article starts with a general and concise comparison between the properties of conducting polymers and conducting polymer nanocomposites. Next, the current applications of conductive polymer-based nanocomposites of some important conducting polymers such as PANI, PPy, and PEDOT in enzymatic and nonenzymatic electrochemical biosensors are overviewed. This review article covers an 8-year period beginning in 2010. © 2018 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Ultra-low temperature curable nano-silver conductive adhesive for piezoelectric composite material
NASA Astrophysics Data System (ADS)
Yan, Chao; Liao, Qingwei; Zhou, Xingli; Wang, Likun; Zhong, Chao; Zhang, Di
2018-01-01
Limited by the low thermal resistance of composite material, ultra-low temperature curable conductive silver adhesive with curing temperature less than 100 °C needed urgently for the surface conduction treatment of piezoelectric composite material. An ultra-low temperature curable nano-silver conductive adhesive with high adhesion strength for the applications of piezoelectric composite material was investigated. The crystal structure of cured adhesive, SEM/EDS analysis, thermal analysis, adhesive properties and conductive properties of different content of nano-silver filler or micron-silver doping samples were studied. The results show that with 60 wt.% nano-silver filler the ultra-low temperature curable conductive silver adhesive had the relatively good conductivity as volume resistivity of 2.37 × 10-4 Ω cm, and good adhesion strength of 5.13 MPa. Minor micron-doping (below 15 wt.%) could improve conductivity, but would decrease other properties. The ultra-low temperature curable nano-silver conductive adhesive could successfully applied to piezoelectric composite material.
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Conductive properties of methanogenic biofilms.
Li, Cheng; Lesnik, Keaton Larson; Liu, Hong
2018-02-01
Extracellular electron transfer between syntrophic partners needs to be efficiently maintained in methanogenic environments. Direct extracellular electron transfer via electrical current is an alternative to indirect hydrogen transfer but requires construction of conductive extracellular structures. Conductive mechanisms and relationship between conductivity and the community composition in mixed-species methanogenic biofilms are not well understood. The present study investigated conductive behaviors of methanogenic biofilms and examined the correlation between biofilm conductivity and community composition between different anaerobic biofilms enriched from the same inoculum. Highest conductivity observed in methanogenic biofilms was 71.8±4.0μS/cm. Peak-manner response of conductivity upon changes over a range of electrochemical potentials suggests that electron transfer in methanogenic biofilms occurs through redox driven super-exchange. The strong correlation observed between biofilm conductivity and Geobacter spp. in the metabolically diverse anaerobic communities suggests that the efficiency of DEET may provide pressure for microbial communities to select for species that can produce electrical conduits. Copyright © 2017 Elsevier B.V. All rights reserved.
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Li, Baowen; Wang, Jiao; Wang, Lei; Zhang, Gang
2005-03-01
We study anomalous heat conduction and anomalous diffusion in low-dimensional systems ranging from nonlinear lattices, single walled carbon nanotubes, to billiard gas channels. We find that in all discussed systems, the anomalous heat conductivity can be connected with the anomalous diffusion, namely, if energy diffusion is sigma(2)(t)=2Dt(alpha) (0
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Carbon-Nanotube Conductive Layers for Thin-Film Solar Cells
NASA Technical Reports Server (NTRS)
Landis, Geoffrey A.
2005-01-01
Thin, transparent layers comprising mats of carbon nanotubes have been proposed for providing lateral (that is, inplane) electrical conductivities for collecting electric currents from the front surfaces of the emitter layers of thin-film solar photovoltaic cells. Traditionally, thin, semitransparent films of other electrically conductive materials (usually, indium tin oxide, zinc oxide, or cadmium sulfide) have been used for this purpose. As in the cases of the traditional semitransparent conductive films, the currents collected by the nanotube layers would, in turn, be further collected by front metal contact stripes. Depending on details of a specific solar-cell design, the layer of carbon nanotubes would be deposited in addition to, or instead of, a semitransparent layer of one of these traditional conductive materials (see figure). The proposal is expected to afford the following advantages: The electrical conductivity of the carbon- nanotube layer would exceed that of the corresponding semitransparent layer of traditional electrically conductive material. The greater electrical conductivity of the carbon-nanotube layer would make it possible to retain adequate lateral electrical conductivity while reducing the thickness of, or eliminating entirely, the traditional semitransparent conductive layer. As a consequence of thinning or elimination of the traditional semitransparent conductive layer, less light would be absorbed, so that more of the incident light would be available for photovoltaic conversion. The greater electrical conductivity of the carbon-nanotube layer would make it possible to increase the distance between front metal contact stripes, in addition to (or instead of) thinning or eliminating the layer of traditional semitransparent conductive material. Consequently, the fraction of solar-cell area shadowed by front metal contact stripes would be reduced again, making more of the incident light available for photovoltaic conversion. The electrical conductivities of individual carbon nanotubes can be so high that the mat of carbon nanotubes could be made sparse enough to be adequately transparent while affording adequate lateral electrical conductivity of the mat as a whole. The thickness of the nanotube layer would be chosen so that the layer would contribute significant lateral electrical conductivity, yet would be as nearly transparent as possible to incident light. A typical thickness for satisfying these competing requirements is expected to lie between 50 and 100 nm. The optimum thickness must be calculated by comparing the lateral electrical conductivity, the distance between front metal stripes, and the amount of light lost by absorption in the nanotube layer.
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Wojnarowska, Z; Swiety-Pospiech, A; Grzybowska, K; Hawelek, L; Paluch, M; Ngai, K L
2012-04-28
The pharmaceuticals, procaine hydrochloride and procainamide hydrochloride, are glass-forming as well as ionically conducting materials. We have made dielectric measurements at ambient and elevated pressures to characterize the dynamics of the ion conductivity relaxation in these pharmaceuticals, and calorimetric measurements for the structural relaxation. Perhaps due to their special chemical and physical structures, novel features are found in the ionic conductivity relaxation of these pharmaceuticals. Data of conductivity relaxation in most ionic conductors when represented by the electric loss modulus usually show a single resolved peak in the electric modulus loss M(")(f) spectra. However, in procaine hydrochloride and procainamide hydrochloride we find in addition another resolved loss peak at higher frequencies over a temperature range spanning across T(g). The situation is analogous to many non-ionic glass-formers showing the presence of the structural α-relaxation together with the Johari-Goldstein (JG) β-relaxation. Naturally the analogy leads us to name the slower and faster processes resolved in procaine hydrochloride and procainamide hydrochloride as the primary α-conductivity relaxation and the secondary β-conductivity relaxation, respectively. The analogy of the β-conductivity relaxation in procaine HCl and procainamide HCl with JG β-relaxation in non-ionic glass-formers goes further by the finding that the β-conductivity is strongly related to the α-conductivity relaxation at temperatures above and below T(g). At elevated pressure but compensated by raising temperature to maintain α-conductivity relaxation time constant, the data show invariance of the ratio between the β- and the α-conductivity relaxation times to changes of thermodynamic condition. This property indicates that the β-conductivity relaxation has fundamental importance and is indispensable as the precursor of the α-conductivity relaxation, analogous to the relation found between the Johari-Goldstein β-relaxation and the structural α-relaxation in non-ionic glass-forming systems. The novel features of the ionic conductivity relaxation are brought out by presenting the measurements in terms of the electric modulus or permittivity. If presented in terms of conductivity, the novel features are lost. This warns against insisting that a log-log plot of conductivity vs. frequency is optimal to reveal and interpret the dynamics of ionic conductors.
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34 CFR 74.42 - Codes of conduct.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Procurement Standards § 74.42 Codes of conduct. The recipient shall maintain written standards of conduct... interest is not substantial or the gift is an unsolicited item of nominal value. The standards of conduct...
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Wang, Ning; Chen, Haijun; He, Hongcai; Norimatsu, Wataru; Kusunoki, Michiko; Koumoto, Kunihito
2013-01-01
Authors reported an effective path to increase the electrical conductivity while to decrease the thermal conductivity, and thus to enhance the ZT value by nano-inclusions. By this method, the ZT value of Nb-doped SrTiO3 was enhanced 9-fold by yttria stabilized zirconia (YSZ) nano-inclusions. YSZ inclusions, located inside grain and in triple junction, can reduce the thermal conductivity by effective interface phonon scattering, enhance the electrical conductivity by promoting the abnormal grain growth, and thus lead to the obvious enhancement of ZT value, which strongly suggests that, it is possible to not only reduce the thermal conductivity, but also increase the electrical conductivity by nano-inclusions with low thermal conductivity. This study will give some useful enlightenment to the preparation of high-performance oxide thermoelectric materials. PMID:24316665
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Electrical conductivity and modulus formulation in zinc modified bismuth boro-tellurite glasses
NASA Astrophysics Data System (ADS)
Dhankhar, Sunil; Kundu, R. S.; Dult, Meenakshi; Murugavel, S.; Punia, R.; Kishore, N.
2016-09-01
The ac conductivity of zinc modified tellurium based quaternary glasses having composition 60 TeO2-10 B2O3-(30 - x) Bi2O3-x ZnO; x = 10, 15, 20, 25 and 30 has been investigated in the frequency range 10-1-105 Hz and in temperature range 483-593 K. Frequency and temperature dependent ac conductivity found to obey Jonscher power law modified by Almond-West. DC conductivity, crossover frequency and frequency exponent have been estimated from the fitting of the experimental data of conductivity with Jonscher power law modified by Almond-West. The ac conductivity and its frequency exponent have been analyzed by various theoretical models. In presently studied glasses ac conduction takes place via tunneling of overlapping large polaron tunneling. Activation energy is found to be increased with increase in zinc content and dc conduction takes place via variable range hopping proposed by Mott with some modification suggested by Punia et al. The value of the stretched exponent ( β) obtained by fitting of M^' ' }} reveals the presence of non-Debye type relaxation. Scaling spectra of ac conductivity and electric modulus collapse into a single master curve for all compositions and temperatures, reveals the presence of composition and temperature independent conduction and relaxation process in these glasses. Activation energy of conduction ( W) and electric modulus ( E R ) are nearly equal, indicating that polaron have to overcome the same energy barrier during conduction as well as relaxation processes.
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Determination of Thermal Conductivity of Silicate Matrix for Applications in Effective Media Theory
NASA Astrophysics Data System (ADS)
Fiala, Lukáš; Jerman, Miloš; Reiterman, Pavel; Černý, Robert
2018-02-01
Silicate materials have an irreplaceable role in the construction industry. They are mainly represented by cement-based- or lime-based materials, such as concrete, cement mortar, or lime plaster, and consist of three phases: the solid matrix and air and water present in the pores. Therefore, their effective thermal conductivity depends on thermal conductivities of the involved phases. Due to the time-consuming experimental determination of the effective thermal conductivity, its calculation by means of homogenization techniques presents a reasonable alternative. In the homogenization theory, both volumetric content and particular property of each phase need to be identified. For porous materials the most problematic part is to accurately identify thermal conductivity of the solid matrix. Due to the complex composition of silicate materials, the thermal conductivity of the matrix can be determined only approximately, based on the knowledge of thermal conductivities of its major compounds. In this paper, the thermal conductivity of silicate matrix is determined using the measurement of a sufficiently large set of experimental data. Cement pastes with different open porosities are prepared, dried, and their effective thermal conductivity is determined using a transient heat-pulse method. The thermal conductivity of the matrix is calculated by means of extrapolation of the effective thermal conductivity versus porosity functions to zero porosity. Its practical applicability is demonstrated by calculating the effective thermal conductivity of a three-phase silicate material and comparing it with experimental data.
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Sleifer, Pricila; Didoné, Dayane Domeneghini; Keppeler, Ísis Bicca; Bueno, Claudine Devicari; Riesgo, Rudimar dos Santos
2017-01-01
Introduction The tone-evoked auditory brainstem responses (tone-ABR) enable the differential diagnosis in the evaluation of children until 12 months of age, including those with external and/or middle ear malformations. The use of auditory stimuli with frequency specificity by air and bone conduction allows characterization of hearing profile. Objective The objective of our study was to compare the results obtained in tone-ABR by air and bone conduction in children until 12 months, with agenesis of the external auditory canal. Method The study was cross-sectional, observational, individual, and contemporary. We conducted the research with tone-ABR by air and bone conduction in the frequencies of 500 Hz and 2000 Hz in 32 children, 23 boys, from one to 12 months old, with agenesis of the external auditory canal. Results The tone-ABR thresholds were significantly elevated for air conduction in the frequencies of 500 Hz and 2000 Hz, while the thresholds of bone conduction had normal values in both ears. We found no statistically significant difference between genders and ears for most of the comparisons. Conclusion The thresholds obtained by bone conduction did not alter the thresholds in children with conductive hearing loss. However, the conductive hearing loss alter all thresholds by air conduction. The tone-ABR by bone conduction is an important tool for assessing cochlear integrity in children with agenesis of the external auditory canal under 12 months. PMID:29018492
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Origin of conductivity anomalies in the asthenosphere
NASA Astrophysics Data System (ADS)
Yoshino, T.; Zhang, B.
2013-12-01
Electrical conductivity anomalies with anisotropy parallel to the plate motion have been observed beneath the oceanic lithosphere by electromagnetic studies (e.g., Evans et al., 2005; Baba et al., 2010; Naif et al., 2013). Electrical conductivity of the oceanic asthenosphere at ~100 km depth is very high, about 10-2 to 10-1 S/m. This zone is also known in seismology as the low velocity zone. Since Karato (1990) first suggested that electrical conductivity is sensitive to water content in NAMs, softening of asthenosphere has been regarded as a good indicator for constraining the distribution of water. There are two difficulties to explain the observed conductivity features in the asthenosphere. Recent publications on electrical conductivity of hydrous olivine suggested that olivine with the maximum soluble H2O content at the top of the asthenosphere has much lower conductivity less than 0.1 S/m (e.g., Yoshino et al., 2006; 2009a; Poe et al., 2010; Du Frane and Tyburczy, 2012; Yang, 2012), which is a typical value of conductivity anomaly observed in the oceanic mantle. Partial melting has been considered as an attractive agent for substantially raising the conductivity in this region (Shankland and Waff, 1977), because basaltic melt has greater electrical conductivity (> 100.5 S/m) and high wetting properties. However, dry mantle peridotite cannot reach the solidus temperature at depth 100 km. Volatile components can dramatically reduce melting temperature, even if its amount is very small. Recent studies on conductivity measurement of volatile-bearing melt suggest that conductivity of melt dramatically increases with increasing volatile components (H2O: Ni et al., 2010a, b; CO2: Gaillard et al., 2008; Yoshino et al., 2010; 2012a). Because incipient melt includes higher amount of volatile components, conductivity enhancement by the partial melt is very effective at temperatures just above that of the volatile-bearing peridotite solidus. In this study, the electrical conductivity of peridotite with trace amount of volatile phases was measured in single crystal olivine capsule to protect escape of water from the sample at 3 GPa. The conductivity values were significantly higher than those of dry peridotite, suggesting that the observed conductivity anomalies at the asthenosphere are caused by a presence of trace amount of volatile component in fluid or melt. On the other hand, conductivity of partial molten peridotite measured under shear showed that the conductivity parallel to the shear direction becomes one order of magnitude higher than that normal direction. These observations suggest that partial melting can explain softening and the observed geophysical anomalies of asthenosphere.
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Nanowire structures and electrical devices
Bezryadin, Alexey; Remeika, Mikas
2010-07-06
The present invention provides structures and devices comprising conductive segments and conductance constricting segments of a nanowire, such as metallic, superconducting or semiconducting nanowire. The present invention provides structures and devices comprising conductive nanowire segments and conductance constricting nanowire segments having accurately selected phases including crystalline and amorphous states, compositions, morphologies and physical dimensions, including selected cross sectional dimensions, shapes and lengths along the length of a nanowire. Further, the present invention provides methods of processing nanowires capable of patterning a nanowire to form a plurality of conductance constricting segments having selected positions along the length of a nanowire, including conductance constricting segments having reduced cross sectional dimensions and conductance constricting segments comprising one or more insulating materials such as metal oxides.
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Thermal conductivity of pillared graphene-epoxy nanocomposites using molecular dynamics
NASA Astrophysics Data System (ADS)
Lakshmanan, A.; Srivastava, S.; Ramazani, A.; Sundararaghavan, V.
2018-04-01
Thermal conductivity in a pillared graphene-epoxy nanocomposite (PGEN) is studied using equilibrium molecular dynamics simulations. PGEN is a proposed material for advanced thermal management applications because it combines high in-plane conductivity of graphene with high axial conductivity of a nanotube to significantly enhance the overall conductivity of the epoxy matrix material. Anisotropic conductivity of PGEN has been compared with that of pristine and functionalized carbon nanotube-epoxy nanocomposites, showcasing the advantages of the unique hierarchical structure of PGEN. Compared to pure carbon allotropes, embedding the epoxy matrix also promotes a weaker dependence of conductivity on thermal variations. These features make this an attractive material for thermal management applications.
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Electrical conduction at domain walls in multiferroic BiFeO3
NASA Astrophysics Data System (ADS)
Seidel, Jan; Martin, Lane; He, Qing; Zhan, Qian; Chu, Ying-Hao; Rother, Axel; Hawkridge, Michael; Maksymovych, Peter; Yu, Pu; Gajek, Martin; Balke, Nina; Kalinin, Sergei; Gemming, Sybille; Wang, Feng; Catalán, Gustau; Scott, James; Spaldin, Nicola; Orenstein, Joseph; Ramesh, Ramamoorthy
2009-03-01
We report the observation of room temperature electronic conductivity at ferroelectric domain walls in BiFeO3. The origin and nature of the observed conductivity is probed using a combination of conductive atomic force microscopy, high resolution transmission electron microscopy and first-principles density functional computations. We show that a structurally driven change in both the electrostatic potential and local electronic structure (i.e., a decrease in band gap) at the domain wall leads to the observed electrical conductivity. We estimate the conductivity in the wall to be several orders of magnitude higher than for the bulk material. Additionally we demonstrate the potential for device applications of such conducting nanoscale features.
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NASA Astrophysics Data System (ADS)
Shibata, K.; Yoshida, K.; Daiguji, K.; Sato, H.; , T., Ii; Hirakawa, K.
2017-10-01
An electric-field control of quantized conductance in metal (gold) quantum point contacts (QPCs) is demonstrated by adopting a liquid-gated electric-double-layer (EDL) transistor geometry. Atomic-scale gold QPCs were fabricated by applying the feedback-controlled electrical break junction method to the gold nanojunction. The electric conductance in gold QPCs shows quantized conductance plateaus and step-wise increase/decrease by the conductance quantum, G0 = 2e2/h, as EDL-gate voltage is swept, demonstrating a modulation of the conductance of gold QPCs by EDL gating. The electric-field control of conductance in metal QPCs may open a way for their application to local charge sensing at room temperature.
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Thermal conductivity of cross-linked polyethylene from molecular dynamics simulation
NASA Astrophysics Data System (ADS)
Xiong, Xue; Yang, Ming; Liu, Changlin; Li, Xiaobo; Tang, Dawei
2017-07-01
The thermal conductivity of cross-linked bulk polyethylene is studied using molecular dynamics simulation. The atomic structure of the cross-linked polyethylene (PEX) is generated through simulated bond formation using LAMMPS. The thermal conductivity of PEX is studied with different degrees of crosslinking, chain length, and tensile strain. Generally, the thermal conductivity increases with the increasing degree of crosslinking. When the length of the primitive chain increases, the thermal conductivity increases linearly. When the polymer is stretched along one direction, the thermal conductivity increases in the stretched direction and decreases in the direction perpendicular to it. However, the thermal conductivity varies slightly when the polymer is stretched in three directions simultaneously.
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A percolation model for electrical conduction in wood with implications for wood-water relations
Samuel L. Zelinka; Samuel V. Glass; Donald S. Stone
2008-01-01
The first models used to describe electrical conduction in cellulosic materials involved conduction pathways through free water. These models were abandoned in the middle of the 20th century. This article re-evaluates the theory of conduction in wood by using a percolation model that describes electrical conduction in terms of overlapping paths of loosely bound or...
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A singlechip-computer-controlled conductivity meter based on conductance-frequency transformation
NASA Astrophysics Data System (ADS)
Chen, Wenxiang; Hong, Baocai
2005-02-01
A portable conductivity meter controlled by singlechip computer was designed. The instrument uses conductance-frequency transformation method to measure the conductivity of solution. The circuitry is simple and reliable. Another feature of the instrument is that the temperature compensation is realised by changing counting time of the timing counter. The theoretical based and the usage of temperature compensation are narrated.
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30 CFR 250.1151 - How often must I conduct well production tests?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 2 2010-07-01 2010-07-01 false How often must I conduct well production tests... Requirements Well Tests and Surveys § 250.1151 How often must I conduct well production tests? (a) You must conduct well production tests as shown in the following table: You must conduct: And you must submit to...
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Laboratory-based electrical conductivity at Martian mantle conditions
NASA Astrophysics Data System (ADS)
Verhoeven, Olivier; Vacher, Pierre
2016-12-01
Information on temperature and composition of planetary mantles can be obtained from electrical conductivity profiles derived from induced magnetic field analysis. This requires a modeling of the conductivity for each mineral phase at conditions relevant to planetary interiors. Interpretation of iron-rich Martian mantle conductivity profile therefore requires a careful modeling of the conductivity of iron-bearing minerals. In this paper, we show that conduction mechanism called small polaron is the dominant conduction mechanism at temperature, water and iron content conditions relevant to Mars mantle. We then review the different measurements performed on mineral phases with various iron content. We show that, for all measurements of mineral conductivity reported so far, the effect of iron content on the activation energy governing the exponential decrease in the Arrhenius law can be modeled as the cubic square root of the iron content. We recast all laboratory results on a common generalized Arrhenius law for iron-bearing minerals, anchored on Earth's mantle values. We then use this modeling to compute a new synthetic profile of Martian mantle electrical conductivity. This new profile matches perfectly, in the depth range [100,1000] km, the electrical conductivity profile recently derived from the study of Mars Global Surveyor magnetic field measurements.
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Electronic Conductivity in Biomimetic α-Helical Peptide Nanofibers and Gels.
Ing, Nicole L; Spencer, Ryan K; Luong, Son H; Nguyen, Hung D; Hochbaum, Allon I
2018-03-27
Examples of long-range electronic conductivity are rare in biological systems. The observation of micrometer-scale electronic transport through protein wires produced by bacteria is therefore notable, providing an opportunity to study fundamental aspects of conduction through protein-based materials and natural inspiration for bioelectronics materials. Borrowing sequence and structural motifs from these conductive protein fibers, we designed self-assembling peptides that form electronically conductive nanofibers under aqueous conditions. Conductivity in these nanofibers is distinct for two reasons: first, they support electron transport over distances orders of magnitude greater than expected for proteins, and second, the conductivity is mediated entirely by amino acids lacking extended conjugation, π-stacking, or redox centers typical of existing organic and biohybrid semiconductors. Electrochemical transport measurements show that the fibers support ohmic electronic transport and a metallic-like temperature dependence of conductance in aqueous buffer. At higher solution concentrations, the peptide monomers form hydrogels, and comparisons of the structure and electronic properties of the nanofibers and gels highlight the critical roles of α-helical secondary structure and supramolecular ordering in supporting electronic conductivity in these materials. These findings suggest a structural basis for long-range electronic conduction mechanisms in peptide and protein biomaterials.
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Effective Thermal Conductivity of High Porosity Open Cell Nickel Foam
NASA Technical Reports Server (NTRS)
Sullins, Alan D.; Daryabeigi, Kamran
2001-01-01
The effective thermal conductivity of high-porosity open cell nickel foam samples was measured over a wide range of temperatures and pressures using a standard steady-state technique. The samples, measuring 23.8 mm, 18.7 mm, and 13.6 mm in thickness, were constructed with layers of 1.7 mm thick foam with a porosity of 0.968. Tests were conducted with the specimens subjected to temperature differences of 100 to 1000 K across the thickness and at environmental pressures of 10(exp -4) to 750 mm Hg. All test were conducted in a gaseous nitrogen environment. A one-dimensional finite volume numerical model was developed to model combined radiation/conduction heat transfer in the foam. The radiation heat transfer was modeled using the two-flux approximation. Solid and gas conduction were modeled using standard techniques for high porosity media. A parameter estimation technique was used in conjunction with the measured and predicted thermal conductivities at pressures of 10(exp -4) and 750 mm Hg to determine the extinction coefficient, albedo of scattering, and weighting factors for modeling the conduction thermal conductivity. The measured and predicted conductivities over the intermediate pressure values differed by 13%.
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Pingault, Jean-Baptiste; Rijsdijk, Frühling; Zheng, Yao; Plomin, Robert; Viding, Essi
2015-01-01
The development of conduct problems in childhood and adolescence is associated with adverse long-term outcomes, including psychiatric morbidity. Although genes constitute a proven factor of stability in conduct problems, less is known regarding their role in conduct problems’ developmental course (i.e. systematic age changes, for instance linear increases or decreases).Mothers rated conduct problems from age 4 to 16 years in 10,038 twin pairs from the Twins Early Development Study. Individual differences in the baseline level (.78; 95% CI: .68-.88) and the developmental course of conduct problems (.73; 95% CI: .60-.86) were under high and largely independent additive genetic influences. Shared environment made a small contribution to the baseline level but not to the developmental course of conduct problems. These results show that genetic influences not only contribute to behavioural stability but also explain systematic change in conduct problems. Different sets of genes may be associated with the developmental course versus the baseline level of conduct problems. The structure of genetic and environmental influences on the development of conduct problems suggests that repeated preventive interventions at different developmental stages might be necessary to achieve a long-term impact. PMID:25944445
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Pingault, Jean-Baptiste; Rijsdijk, Frühling; Zheng, Yao; Plomin, Robert; Viding, Essi
2015-05-06
The development of conduct problems in childhood and adolescence is associated with adverse long-term outcomes, including psychiatric morbidity. Although genes constitute a proven factor of stability in conduct problems, less is known regarding their role in conduct problems' developmental course (i.e. systematic age changes, for instance linear increases or decreases).Mothers rated conduct problems from age 4 to 16 years in 10,038 twin pairs from the Twins Early Development Study. Individual differences in the baseline level (.78; 95% CI: .68-.88) and the developmental course of conduct problems (.73; 95% CI: .60-.86) were under high and largely independent additive genetic influences. Shared environment made a small contribution to the baseline level but not to the developmental course of conduct problems. These results show that genetic influences not only contribute to behavioural stability but also explain systematic change in conduct problems. Different sets of genes may be associated with the developmental course versus the baseline level of conduct problems. The structure of genetic and environmental influences on the development of conduct problems suggests that repeated preventive interventions at different developmental stages might be necessary to achieve a long-term impact.
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Pan, Pan; Wu, Shaopeng; Hu, Xiaodi; Liu, Gang; Li, Bo
2017-02-23
Conductive asphalt concrete with high thermal conductivity has been proposed to improve the solar energy collection and snow melting efficiencies of asphalt solar collector (ASC). This paper aims to provide some insight into choosing the basic materials for preparation of conductive asphalt concrete, as well as determining the evolution of thermal characteristics affected by environmental factors. The thermal properties of conductive asphalt concrete were studied by the Thermal Constants Analyzer. Experimental results showed that aggregate and conductive filler have a significant effect on the thermal properties of asphalt concrete, while the effect of asphalt binder was not evident due to its low proportion. Utilization of mineral aggregate and conductive filler with higher thermal conductivity is an efficient method to prepare conductive asphalt concrete. Moreover, change in thermal properties of asphalt concrete under different temperature and moisture conditions should be taken into account to determine the actual thermal properties of asphalt concrete. There was no noticeable difference in thermal properties of asphalt concrete before and after aging. Furthermore, freezing-thawing cycles strongly affect the thermal properties of conductive asphalt concrete, due to volume expansion and bonding degradation.
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Consideration of Conductive Motor Winding Materials at Room and Elevated Temperatures
NASA Technical Reports Server (NTRS)
de Groh, Henry C., III
2015-01-01
A brief history of conductive motor winding materials is presented, comparing various metal motor winding materials and their properties in terms of conductivity, density and cost. The proposed use of carbon nanotubes (CNTs) and composites incorporating CNTs is explored as a potential way to improve motor winding conductivity, density, and reduce motor size which are important to electric aircraft technology. The conductivity of pure Cu, a CNT yarn, and a dilute Cu-CNT composite was measured at room temperature and at several temperatures up to 340 C. The conductivity of the Cu-CNT composite was about 3 percent lower than pure copper's at all temperatures measured. The conductivity of the CNT yarn was about 200 times lower than copper's, however, the yarn's conductivity dropped less with increasing temperature compared to Cu. It is believed that the low conductivity of the yarn is due primarily to high interfacial resistances and the presence of CNTs with low, semiconductor like electrical properties (s-CNT). It is believed the conductivity of the CNT-Cu composite could be improved by not using s-CNT, and instead using only CNTs with high, metallic like electrical properties (m-CNT); and by increasing the vol% m-CNTs.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Lappin, A.R.; VanBuskirk, R.G.; Enniss, D.O.
1982-03-01
Thermal-conductivity and bulk-property measurements were made on welded and nonwelded silicic tuffs from the upper portion of Hole USW-G1, located near the southwestern margin of the Nevada Test Site. Bulk-property measurements were made by standard techniques. Thermal conductivities were measured at temperatures as high as 280{sup 0}C, confining pressures to 10 MPa, and pore pressures to 1.5 MPa. Extrapolation of measured saturated conductivities to zero porosity suggests that matrix conductivity of both zeolitized and devitrified tuffs is independent of stratigraphic position, depth, and probably location. This fact allows development of a thermal-conductivity stratigraphy for the upper portion of Hole G1.more » Estimates of saturated conductivities of zeolitized nonwelded tuffs and devitrified tuffs below the water table appear most reliable. Estimated conductivities of saturated densely welded devitrified tuffs above the water table are less reliable, due to both internal complexity and limited data presently available. Estimation of conductivity of dewatered tuffs requires use of different air thermal conductivities in devitrified and zeolitized samples. Estimated effects of in-situ fracturing generally appear negligible.« less
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Wang, Jiawei; Zhou, Yuqi; Sun, Xiaodong; Ma, Qingyu; Zhang, Dong
2016-04-01
As a multiphysics imaging approach, magnetoacoustic tomography with magnetic induction (MAT-MI) works on the physical mechanism of magnetic excitation, acoustic vibration, and transmission. Based on the theoretical analysis of the source vibration, numerical studies are conducted to simulate the pathological changes of tissues for a single-layer cylindrical conductivity gradual-varying model and estimate the strengths of sources inside the model. The results suggest that the inner source is generated by the product of the conductivity and the curl of the induced electric intensity inside conductivity homogeneous medium, while the boundary source is produced by the cross product of the gradient of conductivity and the induced electric intensity at conductivity boundary. For a biological tissue with low conductivity, the strength of boundary source is much higher than that of the inner source only when the size of conductivity transition zone is small. In this case, the tissue can be treated as a conductivity abrupt-varying model, ignoring the influence of inner source. Otherwise, the contributions of inner and boundary sources should be evaluated together quantitatively. This study provide basis for further study of precise image reconstruction of MAT-MI for pathological tissues.
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Pan, Pan; Wu, Shaopeng; Hu, Xiaodi; Liu, Gang; Li, Bo
2017-01-01
Conductive asphalt concrete with high thermal conductivity has been proposed to improve the solar energy collection and snow melting efficiencies of asphalt solar collector (ASC). This paper aims to provide some insight into choosing the basic materials for preparation of conductive asphalt concrete, as well as determining the evolution of thermal characteristics affected by environmental factors. The thermal properties of conductive asphalt concrete were studied by the Thermal Constants Analyzer. Experimental results showed that aggregate and conductive filler have a significant effect on the thermal properties of asphalt concrete, while the effect of asphalt binder was not evident due to its low proportion. Utilization of mineral aggregate and conductive filler with higher thermal conductivity is an efficient method to prepare conductive asphalt concrete. Moreover, change in thermal properties of asphalt concrete under different temperature and moisture conditions should be taken into account to determine the actual thermal properties of asphalt concrete. There was no noticeable difference in thermal properties of asphalt concrete before and after aging. Furthermore, freezing–thawing cycles strongly affect the thermal properties of conductive asphalt concrete, due to volume expansion and bonding degradation. PMID:28772580
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NASA Astrophysics Data System (ADS)
Titus, Jitto; Thakur, Mrinal
2002-03-01
Conjugation is not a prerequisite for electrical conductivity in polymers. Nonconjugated polymers having at least one double bond in the repeat can become conductive upon doping. Polyisoprene having one double bond repeating after three single bonds in the backbone becomes conductive upon doping with electron acceptors such as iodine.^1 The conductivity of doped polyisoprene is about 10-2 - 10-1 ohm-1cm-1. Poly(allocimene) has on the average one double bond repeating after two single bonds in the polymer backbone. The conductivity of poly(allocimene) is about 1 ohm-1cm-1 upon iodine doping. For polyacetylene, the conductivity upon iodine doping is about 100 ohm-1cm-1. There seems to be a power law dependence of conductivity on the fraction of double bonds in the repeat: σ ~ 10^5(f)^10, where σ is the conductivity in ohm-1cm-1, f is the number fraction of double bonds (e.g. 0.25 in polyisoprene, 0.33 in poly(allocimene) and 0.5 in polyacetylene). The conductivity depends partly on substituents and the morphology of the polymer as well. 1. M. Thakur, Macromolecules, 21 661 (1988); J. Macromol. Sci.-PAC, A38.12, Dec., (2001).
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Thermal conductivity engineering of bulk and one-dimensional Si-Ge nanoarchitectures.
Kandemir, Ali; Ozden, Ayberk; Cagin, Tahir; Sevik, Cem
2017-01-01
Various theoretical and experimental methods are utilized to investigate the thermal conductivity of nanostructured materials; this is a critical parameter to increase performance of thermoelectric devices. Among these methods, equilibrium molecular dynamics (EMD) is an accurate technique to predict lattice thermal conductivity. In this study, by means of systematic EMD simulations, thermal conductivity of bulk Si-Ge structures (pristine, alloy and superlattice) and their nanostructured one dimensional forms with square and circular cross-section geometries (asymmetric and symmetric) are calculated for different crystallographic directions. A comprehensive temperature analysis is evaluated for selected structures as well. The results show that one-dimensional structures are superior candidates in terms of their low lattice thermal conductivity and thermal conductivity tunability by nanostructuring, such as by diameter modulation, interface roughness, periodicity and number of interfaces. We find that thermal conductivity decreases with smaller diameters or cross section areas. Furthermore, interface roughness decreases thermal conductivity with a profound impact. Moreover, we predicted that there is a specific periodicity that gives minimum thermal conductivity in symmetric superlattice structures. The decreasing thermal conductivity is due to the reducing phonon movement in the system due to the effect of the number of interfaces that determine regimes of ballistic and wave transport phenomena. In some nanostructures, such as nanowire superlattices, thermal conductivity of the Si/Ge system can be reduced to nearly twice that of an amorphous silicon thermal conductivity. Additionally, it is found that one crystal orientation, [Formula: see text]100[Formula: see text], is better than the [Formula: see text]111[Formula: see text] crystal orientation in one-dimensional and bulk SiGe systems. Our results clearly point out the importance of lattice thermal conductivity engineering in bulk and nanostructures to produce high-performance thermoelectric materials.
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Thermal conductivity engineering of bulk and one-dimensional Si-Ge nanoarchitectures
Kandemir, Ali; Ozden, Ayberk; Cagin, Tahir; Sevik, Cem
2017-01-01
Various theoretical and experimental methods are utilized to investigate the thermal conductivity of nanostructured materials; this is a critical parameter to increase performance of thermoelectric devices. Among these methods, equilibrium molecular dynamics (EMD) is an accurate technique to predict lattice thermal conductivity. In this study, by means of systematic EMD simulations, thermal conductivity of bulk Si-Ge structures (pristine, alloy and superlattice) and their nanostructured one dimensional forms with square and circular cross-section geometries (asymmetric and symmetric) are calculated for different crystallographic directions. A comprehensive temperature analysis is evaluated for selected structures as well. The results show that one-dimensional structures are superior candidates in terms of their low lattice thermal conductivity and thermal conductivity tunability by nanostructuring, such as by diameter modulation, interface roughness, periodicity and number of interfaces. We find that thermal conductivity decreases with smaller diameters or cross section areas. Furthermore, interface roughness decreases thermal conductivity with a profound impact. Moreover, we predicted that there is a specific periodicity that gives minimum thermal conductivity in symmetric superlattice structures. The decreasing thermal conductivity is due to the reducing phonon movement in the system due to the effect of the number of interfaces that determine regimes of ballistic and wave transport phenomena. In some nanostructures, such as nanowire superlattices, thermal conductivity of the Si/Ge system can be reduced to nearly twice that of an amorphous silicon thermal conductivity. Additionally, it is found that one crystal orientation, <100>, is better than the <111> crystal orientation in one-dimensional and bulk SiGe systems. Our results clearly point out the importance of lattice thermal conductivity engineering in bulk and nanostructures to produce high-performance thermoelectric materials. PMID:28469733
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Formation of conductive polymers using nitrosyl ion as an oxidizing agent
Choi, Kyoung-Shin; Jung, Yongju; Singh, Nikhilendra
2016-06-07
A method of forming a conductive polymer deposit on a substrate is disclosed. The method may include the steps of preparing a composition comprising monomers of the conductive polymer and a nitrosyl precursor, contacting the substrate with the composition so as to allow formation of nitrosyl ion on the exterior surface of the substrate, and allowing the monomer to polymerize into the conductive polymer, wherein the polymerization is initiated by the nitrosyl ion and the conductive polymer is deposited on the exterior surface of the substrate. The conductive polymer may be polypyrrole.
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Sealed substrate carrier for electroplating
Ganti, Kalyana Bhargava [Fremont, CA
2012-07-17
One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The substrate carrier includes a non-conductive carrier body on which the substrates are held, and conductive lines are embedded within the carrier body. A conductive bus bar is embedded into a top side of the carrier body and is conductively coupled to the conductive lines. A thermoplastic overmold covers a portion of the bus bar, and there is a plastic-to-plastic bond between the thermoplastic overmold and the non-conductive carrier body. Other embodiments, aspects and features are also disclosed.
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Conductive nanomaterials for printed electronics.
Kamyshny, Alexander; Magdassi, Shlomo
2014-09-10
This is a review on recent developments in the field of conductive nanomaterials and their application in printed electronics, with particular emphasis on inkjet printing of ink formulations based on metal nanoparticles, carbon nanotubes, and graphene sheets. The review describes the basic properties of conductive nanomaterials suitable for printed electronics (metal nanoparticles, carbon nanotubes, and graphene), their stabilization in dispersions, formulations of conductive inks, and obtaining conductive patterns by using various sintering methods. Applications of conductive nanomaterials for electronic devices (transparent electrodes, metallization of solar cells, RFID antennas, TFTs, and light emitting devices) are also briefly reviewed.
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Proton conducting membrane using a solid acid
NASA Technical Reports Server (NTRS)
Haile, Sossina M. (Inventor); Chisholm, Calum (Inventor); Boysen, Dane (Inventor); Narayanan, Sekharipuram R. (Inventor)
2002-01-01
A solid acid material is used as a proton conducting membrane in an electrochemical device. The solid acid material can be one of a plurality of different kinds of materials. A binder can be added, and that binder can be either a nonconducting or a conducting binder. Nonconducting binders can be, for example, a polymer or a glass. A conducting binder enables the device to be both proton conducting and electron conducting. The solid acid material has the general form M.sub.a H.sub.b (XO.sub.t).sub.c.
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Nonlinear DC Conduction Behavior in Graphene Nanoplatelets/Epoxy Resin Composites
NASA Astrophysics Data System (ADS)
Yuan, Yang; Wang, Qingguo; Qu, Zhaoming
2018-01-01
Graphene nanoplatelets (GNPs)/Epoxy resin (ER) with a low percolation threshold were fabricated. Then the nonlinear DC conduction behavior of GNPs/ER composites was investigated, which indicates that dispersion, exfoliation level and conductivity of GNPs in specimens are closely related to the conduction of composites. Moreover, it could be seen that the modified graphene nanoplatelets made in this paper could be successfully used for increasing the electric conductivity of the epoxy resin, and the GNPs/ER composites with nonlinear conduction behavior have a good application prospects in the field of intelligent electromagnetic protection.
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Deposition and post-processing techniques for transparent conductive films
DOE Office of Scientific and Technical Information (OSTI.GOV)
Christoforo, Mark Greyson; Mehra, Saahil; Salleo, Alberto
2017-07-04
In one embodiment, a method is provided for fabrication of a semitransparent conductive mesh. A first solution having conductive nanowires suspended therein and a second solution having nanoparticles suspended therein are sprayed toward a substrate, the spraying forming a mist. The mist is processed, while on the substrate, to provide a semitransparent conductive material in the form of a mesh having the conductive nanowires and nanoparticles. The nanoparticles are configured and arranged to direct light passing through the mesh. Connections between the nanowires provide conductivity through the mesh.
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Complex conductivity of organic-rich shales
NASA Astrophysics Data System (ADS)
Woodruff, W. F.; Revil, A.; Torres-Verdin, C.
2013-12-01
We can accurately determine the intrinsic anisotropy and material properties in the laboratory, providing empirical evidence of transverse isotropy and the polarization of the organic and metallic fractions in saturated and unsaturated shales. We develop two distinct approaches to obtain the complex conductivity tensor from spectral induced polarization (SIP) measurements. Experimental results indicate clear anisotropy, and characterize the effects of thermal maturation, TOC, and pyrite, aiding in the calibration and interpretation of geophysical data. SIP is a non-intrusive measurement, sensitive to the surface conductance of mineral grains, frequency-dependent polarization of the electrical double layer, and bulk conductivity of the pore water. The in-phase and quadrature components depend upon parameters of principal importance in unconventional shale formation evaluation (e.g., the distribution of pore throat sizes, formation factor, permeability, salinity and cation exchange capacity (CEC), fluid saturation and wettability). In addition to the contribution of the electrical double layer of non-conducting minerals to surface conductivity, we have observed a clear relaxation associated with kerogen pyrolysis, pyrite distribution, and evidence that the CEC of the kerogen fraction may also contribute, depending on thermal maturation history. We utilize a recent model for anisotropic complex conductivity, and rigorous experimental protocols to quantify the role of kerogen and pyrolysis on surface and quadrature conductivity in mudrocks. The complex conductivity tensor σ* describes the directional dependence of electrical conduction in a porous medium, and accounts for both conduction and polarization. The complex-valued tensor components are given as σ*ij , where σ'ij represents in-phase and σ"ij denotes quadrature conductivities. The directional dependence of the complex conductivity tensor is relegated to the textural properties of the material. The components of the formation factor and connectivity (tortuosity) tensors Fij and Tij (affecting the bulk and surface conductivity, respectively) are correlated as Fij=TijΦ. Both conductivity and connectivity tensors share the same eigenvectors; the anisotropy ratio is equivalent in TI media. At high pore water salinity, surface and quadrature conductivity share the same bulk tortuosity; when surface conductivity dominates (low salinity), conductivity is controlled by the surface conductance, and the tortuosity of electrical current along mineral surfaces usually higher than that of the pore water. We developed two distinct SIP measurement protocols to obtain the tensor: (1) azimuthal sampling and inversion of phasor potentials through the full-field solution of the Laplace equation; (2) direct measurement of complex conductivity eigenvalues by polarized, single-component stimulus current. Experiments also include unsaturated and saturated measurements with three brines of known salinity and pH, at log-distributed frequencies ranging 1 mHz to 45 kHz. Both azimuthal spectra and eigenvalue spectra validate the theoretical model and illustrate the effectiveness of the protocols themselves. We obtain the textural tensors and invert key parameters including Archie exponents and CEC, and characterize the relaxation phenomena associated with kerogen content and maturity for multiphase fluid systems.
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NASA Astrophysics Data System (ADS)
Katsura, Tomoo; Baba, Kiyoshi; Yoshino, Takashi; Kogiso, Tetsu
2017-10-01
We review the currently available results of laboratory experiments, geochemistry and MT observations and attempt to explain the conductivity structures in the oceanic asthenosphere by constructing mineral-physics models for the depleted mid-oceanic ridge basalt (MORB) mantle (DMM) and volatile-enriched plume mantle (EM) along the normal and plume geotherms. The hopping and ionic conductivity of olivine has a large temperature dependence, whereas the proton conductivity has a smaller dependence. The contribution of proton conduction is small in DMM. Melt conductivity is enhanced by the H2O and CO2 components. The effects of incipient melts with high volatile components on bulk conductivity are significant. The low solidus temperatures of the hydrous carbonated peridotite produce incipient melts in the asthenosphere, which strongly increase conductivity around 100 km depth under older plates. DMM has a conductivity of 10- 1.2 - 1.5 S/m at 100-300 km depth, regardless of the plate age. Plume mantle should have much higher conductivity than normal mantle, due to its high volatile content and high temperatures. The MT observations of the oceanic asthenosphere show a relatively uniform conductivity at 200-300 km depth, consistent with the mineral-physics model. On the other hand, the MT observations show large lateral variations in shallow parts of the asthenosphere despite similar tectonic settings and close locations. Such variations are difficult to explain with the mineral-physics model. High conductivity layers (HCL), which are associated with anisotropy in the direction of the plate motion, have only been observed in the asthenosphere under infant or young plates, but they are not ubiquitous in the oceanic asthenosphere. Although the general features of HCL imply their high-temperature melting origin, the mineral-physics model cannot explain them quantitatively. Much lower conductivity under hotspots, compared with the model plume-mantle conductivity suggests the extraction of volatiles from the plume mantle by the ocean island basalt (OIB) magmatism.
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Atrial electromechanical conduction delay in patients with neurocardiogenic syncope.
Sucu, Murat; Ercan, Suleyman; Uku, Okkes; Davutoglu, Vedat; Altunbas, Gokhan
2014-05-01
We aimed to investigate the presence of atrial electromechanical conduction delay in patients with neurocardiogenic syncope, which was diagnosed with head-up tilt table test (HUTT). A total of 29 patients (mean age: 30.6 ± 15.9 years) with vasovagal syncope, as diagnosed by HUTT, and 23 healthy control subjects (mean age: 34.7 ± 16.3 years) with a negative HUTT were enrolled to the study. Atrial electromechanical conduction delay was defined as the time elapsed from the beginning of the P wave in the electrogardiogram to the beginning of the Am wave in tissue Doppler. There was no statistically significant difference between the groups in terms of interatrial conduction delay, whereas the difference was significant with regard to the right intraatrial electromechanical conduction delay (P < 0.01) and the left intraatrial electromechanical conduction delay (P < 0.0001). There was a negative correlation between the left intraatrial electromechanical conduction delay and the right intraatrial electromechanical conduction delay (r = -0.486, P = 0.001), whereas a positive correlation was present with the interatrial electromechanical conduction delay (r = 0.507, P = 0.001). In this study, the tissue Doppler method revealed that there is left and right intraatrial electromechanical conduction delay in patients with vasovagal syncope. The impact and role of atrial conduction delay as a pathophysiological determinant should be confirmed in further studies. ©2013 Wiley Periodicals, Inc.
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Amone-P Olak, Kennedy; Ovuga, Emilio
2017-05-01
Exposure to war is associated with poor psychosocial outcomes. Yet the effects of different types of war events on various psychosocial outcomes such as conduct problems remain unknown. This study aims to assess whether various war events differ in predicting conduct problems. Using data from an on-going longitudinal research project, the WAYS study, the current article examined the relationship between specific war events and conduct problems in war-affected youth in Northern Uganda (N=539, baseline age=22.39; SD=2.03, range 18-25). Regression analyses were conducted to relate each type of war experience to conduct problems. War categories of "witnessing violence", "deaths", "threat to loved ones" and "sexual abuse" were associated with reporting conduct problems. Multivariable models yielded independent effects of ''witnessing violence'' (β=0.09, 95% CI: 0.01, 0.18) and ''Sexual abuse'' (β=0.09, 95% CI: 0.02, 0.19) on conduct problems while "duration in captivity" independently and negatively predicted conduct problems (β=-0.14, 95% CI: -0.23, -0.06). Types of war events vary in predicting conduct problems and should be considered when designing interventions to alleviate negative consequences of exposure to war. Moreover, longer duration in captivity appear to protect war-affected youth from conduct problems. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
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Amone-P′Olak, Kennedy; Ovuga, Emilio
2017-01-01
Exposure to war is associated with poor psychosocial outcomes. Yet the effects of different types of war events on various psychosocial outcomes such as conduct problems remain unknown. This study aims to assess whether various war events differ in predicting conduct problems. Using data from an on-going longitudinal research project, the WAYS study, the current article examined the relationship between specific war events and conduct problems in war-affected youth in Northern Uganda (N=539, baseline age=22.39; SD=2.03, range 18– 25). Regression analyses were conducted to relate each type of war experience to conduct problems. War categories of “witnessing violence”, “deaths”, “threat to loved ones” and “sexual abuse” were associated with reporting conduct problems. Multivariable models yielded independent effects of “witnessing violence” (β=0.09, 95% CI: 0.01, 0.18) and “Sexual abuse” (β=0.09, 95% CI: 0.02, 0.19) on conduct problems while “duration in captivity” independently and negatively predicted conduct problems (β=−0.14, 95% CI: −0.23, −0.06). Types of war events vary in predicting conduct problems and should be considered when designing interventions to alleviate negative consequences of exposure to war. Moreover, longer duration in captivity appear to protect war-affected youth from conduct problems. PMID:28171768
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Conducting single-molecule magnet materials.
Cosquer, Goulven; Shen, Yongbing; Almeida, Manuel; Yamashita, Masahiro
2018-05-11
Multifunctional molecular materials exhibiting electrical conductivity and single-molecule magnet (SMM) behaviour are particularly attractive for electronic devices and related applications owing to the interaction between electronic conduction and magnetization of unimolecular units. The preparation of such materials remains a challenge that has been pursued by a bi-component approach of combination of SMM cationic (or anionic) units with conducting networks made of partially oxidized (or reduced) donor (or acceptor) molecules. The present status of the research concerning the preparation of molecular materials exhibiting SMM behaviour and electrical conductivity is reviewed, describing the few molecular compounds where both SMM properties and electrical conductivity have been observed. The evolution of this research field through the years is discussed. The first reported compounds are semiconductors in spite being able to present relatively high electrical conductivity, and the SMM behaviour is observed at low temperatures where the electrical conductivity of the materials is similar to that of an insulator. During the recent years, a breakthrough has been achieved with the coexistence of high electrical conductivity and SMM behaviour in a molecular compound at the same temperature range, but so far without evidence of a synergy between these properties. The combination of high electrical conductivity with SMM behaviour requires not only SMM units but also the regular and as far as possible uniform packing of partially oxidized molecules, which are able to provide a conducting network.
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Cheng, Yehong; Zhou, Shanbao; Hu, Ping; Zhao, Guangdong; Li, Yongxia; Zhang, Xinghong; Han, Wenbo
2017-05-03
Graphene aerogels with high surface areas, ultra-low densities and thermal conductivities have been prepared to exploit their wide applications from pollution adsorption to energy storage, supercapacitor, and thermal insulation. However, the low mechanical properties, poor thermal stability and electric conductivity restrict these aerogels' applications. In this paper, we prepared mechanically strong graphene aerogels with large BET surface areas, low thermal conductivities, high thermal stability and electric conductivities via hydrothermal reduction and supercritical ethanol drying. Annealing at 1500 °C resulted in slightly increased thermal conductivity and further improvement in mechanical properties, oxidation temperature and electric conductivity of the graphene aerogel. The large BET surface areas, together with strong mechanical properties, low thermal conductivities, high thermal stability and electrical conductivities made these graphene aerogels feasible candidates for use in a number of fields covering from batteries to sensors, electrodes, lightweight conductor and insulation materials.
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Reduce the Sensitivity of CL-20 by Improving Thermal Conductivity Through Carbon Nanomaterials.
Wang, Shuang; An, Chongwei; Wang, Jingyu; Ye, Baoyun
2018-03-27
The graphene (rGO) and carbon nanotube (CNT) were adopted to enhance the thermal conductivity of CL-20-based composites as conductive fillers. The microstructure features were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD), and tested the properties by differential scanning calorimeter (DSC), static electricity accumulation, special height, thermal conductivity, and detonation velocity. The results showed that the mixture of rGO and CNT had better effect in thermal conductivity than rGO or CNT alone under the same loading (1 wt%) and it formed a three-dimensional heat-conducting network structure to improve the heat property of the system. Besides, the linear fit proved that the thermal conductivity of the CL-20-based composites were negatively correlated with the impact sensitivity, which also explained that the impact sensitivity was significantly reduced after the thermal conductivity increased and the explosive still maintained better energy.
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NASA Astrophysics Data System (ADS)
Jarad, Amer N.; Ibrahim, Kamarulazizi; Ahmed, Nasser M.
2016-07-01
In this work we report preparation and investigation of structural and optical properties of polyaniline conducting polymer. By using sol-gel in spin coating technique to synthesize thin films of conducting polymer polyaniline (PANI). Conducting polymer polyaniline was synthesized by the chemical oxidative polymerization of aniline monomers. The thin films were characterized by technique: Hall effect, High Resolution X-ray diffraction (HR-XRD), Fourier transform infrared (FTIR) spectroscopy, Field emission scanning electron microscopy (FE-SEM), and UV-vis spectroscopy. Polyaniline conductive polymer exhibit amorphous nature as confirmed by HR-XRD. The presence of characteristic bonds of polyaniline was observed from FTIR spectroscopy technique. Electrical and optical properties revealed that (p-type) conductivity PANI with room temperature, the conductivity was 6.289×10-5 (Ω.cm)-1, with tow of absorption peak at 426,805 nm has been attributed due to quantized size of polyaniline conducting polymer.
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Wilcox, R.B.
1991-09-10
A planar transparent light conducting means and an improved optically activated electrical switch made using the novel light conducting means are disclosed. The light conducting means further comprise light scattering means on one or more opposite planar surfaces thereof to transmit light from the light conducting means into adjacent media and reflective means on other surfaces of the light conducting means not containing the light scattering means. The optically activated electrical switch comprises at least two stacked photoconductive wafers, each having electrodes formed on both surfaces thereof, and separated by the planar transparent light conducting means. The light scattering means on the light conducting means face surfaces of the wafers not covered by the electrodes to transmit light from the light conducting means into the photoconductive wafers to uniformly illuminate and activate the switch. 11 figures.
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Preparation of Highly Conductive Yarns by an Optimized Impregnation Process
NASA Astrophysics Data System (ADS)
Amba Sankar, K. N.; Mohanta, Kallol
2017-12-01
We report the development of the electrical conductivity in textile yarns through impregnation and post-treatment of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). The conductive polymer is deposited on fibers, which fills the gap space within the hierarchical structure of the yarns. Organic nonpolar solvents act as reducing agent to increase the density of PEDOT moieties on the yarns, galvanizing increment in conductivity values. Post-treatment by ethylene glycol transforms the resonance configuration of the conductive moieties of conjugated polymer, which helps in further enhancement of electrical conductivity of the yarns. We have optimized the method in terms of loading and conformal change of the polymer to have a lesser resistance of the coated conductive yarns. The minimum resistance achieved has a value of 77 Ωcm-1. This technique of developing conductivity in conventional yarns enables retaining the flexibility of yarns and feeling of softness which would find suitable applications for wearable electronics.
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Inter-hemispheric asymmetry of Pedersen conductance
NASA Astrophysics Data System (ADS)
Deng, Y.; Lu, Y.; Sheng, C.; Yue, X.
2015-12-01
Ionospheric conductance is very important to the magnetosphere-ionosphere coupling in the high latitude region, since it connects the polar cap potential with the currents. Meanwhile, the altitudinal distribution of Pederson conductance gives us a rough idea about the altitudinal distribution of Joule heating at high latitudes. Based on the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) satellites observations of electron density profiles from 2009-2014, Pedersen conductivity has been calculated. A climatologic study of the height-integrated Pedersen conductivities in both E (100-150 km) and F (150-600 km) regions and their ratio in different seasons, solar and geomagnetic conditions have been conducted. A significant inter-hemispheric asymmetry is identified in the seasonal variation. Meanwhile, the conductance in both regions and the conductance ratio show a strong dependence on F10.7 and Ap indices. This result will strongly help our understanding of the inter-hemispheric difference in the high-latitude electrodynamics.
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Reduce the Sensitivity of CL-20 by Improving Thermal Conductivity Through Carbon Nanomaterials
NASA Astrophysics Data System (ADS)
Wang, Shuang; An, Chongwei; Wang, Jingyu; Ye, Baoyun
2018-03-01
The graphene (rGO) and carbon nanotube (CNT) were adopted to enhance the thermal conductivity of CL-20-based composites as conductive fillers. The microstructure features were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD), and tested the properties by differential scanning calorimeter (DSC), static electricity accumulation, special height, thermal conductivity, and detonation velocity. The results showed that the mixture of rGO and CNT had better effect in thermal conductivity than rGO or CNT alone under the same loading (1 wt%) and it formed a three-dimensional heat-conducting network structure to improve the heat property of the system. Besides, the linear fit proved that the thermal conductivity of the CL-20-based composites were negatively correlated with the impact sensitivity, which also explained that the impact sensitivity was significantly reduced after the thermal conductivity increased and the explosive still maintained better energy.
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Apparatus for detecting alpha radiation in difficult access areas
Steadman, Peter; MacArthur, Duncan W.
1997-09-02
An electrostatic alpha radiation detector for measuring alpha radiation emitted from inside an enclosure comprising an electrically conductive expandable electrode for insertion into the enclosure. After insertion, the electrically conductive expandable electrode is insulated from the enclosure and defines a decay cavity between the electrically conductive expandable electrode and the enclosure so that air ions generated in the decay cavity are electrostatically captured by the electrically conductive expandable electrode and the enclosure when an electric potential is applied between the electrically conductive expandable electrode and the enclosure. Indicator means are attached to the electrically conductive expandable electrode for indicating an electrical current produced by generation of the air ions generated in the decay cavity by collisions between air molecules and the alpha particles emitted from the enclosure. A voltage source is connected between the indicator means and the electrically conductive enclosure for creating an electric field between the electrically conductive expandable electrode and the enclosure.
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Heat Transfer Measurement and Modeling in Rigid High-Temperature Reusable Surface Insulation Tiles
NASA Technical Reports Server (NTRS)
Daryabeigi, Kamran; Knutson, Jeffrey R.; Cunnington, George R.
2011-01-01
Heat transfer in rigid reusable surface insulations was investigated. Steady-state thermal conductivity measurements in a vacuum were used to determine the combined contribution of radiation and solid conduction components of heat transfer. Thermal conductivity measurements at higher pressures were then used to estimate the effective insulation characteristic length for gas conduction modeling. The thermal conductivity of the insulation can then be estimated at any temperature and pressure in any gaseous media. The methodology was validated by comparing estimated thermal conductivities with published data on a rigid high-temperature silica reusable surface insulation tile. The methodology was also applied to the alumina enhanced thermal barrier tiles. Thermal contact resistance for thermal conductivity measurements on rigid tiles was also investigated. A technique was developed to effectively eliminate thermal contact resistance on the rigid tile s cold-side surface for the thermal conductivity measurements.
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Differential and directional effects of perfusion on electrical and thermal conductivities in liver.
Podhajsky, Ronald J; Yi, Ming; Mahajan, Roop L
2009-01-01
Two different measurement probes--an electrical probe and a thermal conductivity probe--were designed, fabricated, calibrated, and used in experimental studies on a pig liver model that was designed to control perfusion rates. These probes were fabricated by photolithography and mounted in 1.5-mm diameter catheters. We measured the local impedance and thermal conductivity, respectively, of the artificially perfused liver at different flow rates and, by rotating the probes, in different directions. The results show that both the local electrical conductivity and the thermal conductivity varied location to location, that thermal conductivity increased with decreased distance to large blood vessels, and that significant directional differences exist in both electrical and thermal conductivities. Measurements at different perfusion rates demonstrated that both the local electrical and local thermal conductivities increased linearly with the square root of perfusion rate. These correlations may be of great value to many energy-based biomedical applications.
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Preparation of Highly Conductive Yarns by an Optimized Impregnation Process
NASA Astrophysics Data System (ADS)
Amba Sankar, K. N.; Mohanta, Kallol
2018-03-01
We report the development of the electrical conductivity in textile yarns through impregnation and post-treatment of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). The conductive polymer is deposited on fibers, which fills the gap space within the hierarchical structure of the yarns. Organic nonpolar solvents act as reducing agent to increase the density of PEDOT moieties on the yarns, galvanizing increment in conductivity values. Post-treatment by ethylene glycol transforms the resonance configuration of the conductive moieties of conjugated polymer, which helps in further enhancement of electrical conductivity of the yarns. We have optimized the method in terms of loading and conformal change of the polymer to have a lesser resistance of the coated conductive yarns. The minimum resistance achieved has a value of 77 Ωcm-1. This technique of developing conductivity in conventional yarns enables retaining the flexibility of yarns and feeling of softness which would find suitable␣applications for wearable electronics.
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Modelling the effect of hydration on skin conductivity.
Davies, L; Chappell, P; Melvin, T
2017-08-01
Electrical signals are recorded from and sent into the body via the skin in a number of applications. In practice, skin is often hydrated with liquids having different conductivities so a model was produced in order to determine the relationship between skin impedance and conductivity. A model representing the skin was subjected to a variety of electrical signals. The parts of the model representing the stratum corneum were given different conductivities to represent different levels of hydration. The overall impedance and conductivity of the cells did not vary at frequencies below 40 kHz. Above 40 kHz, levels of increased conductivity caused the overall impedance to decrease. The variation in impedance with conductivity between 5 and 50 mSm -1 can be modelled quadratically while variation in impedance with conductivity between 5 and 5000 mSm -1 can be modelled with a double exponential decay. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
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Thermal conductance of two interface materials and their applications in space systems
NASA Technical Reports Server (NTRS)
Scialdone, J. J.; Clatterbuck, C. H.; Wall, J. L.
1992-01-01
Two polymeric materials, the Cho-Therm 1671 elastomer and the CV-2946 conductive RTV silicone, have been evaluated. Tests were conducted in vacuum and in air, for many clamping pressures, power densities, and as a function of time. Results obtained show that the CV-2946 thermal conductance after 24 hour in vacuum is 0.62 W/sq cm C(4W/sq in C) when clamped with an average pressure of about 350 psi. The maximum conductance of Cho-Therm 1671 is 4.3 W/sq in C at the clamping pressure about 200 psi. After 72 h in vacuum, the conductance reaches a steady 3.4 W/sq in C, independent of clamping pressure. It is concluded that the tightly bolted, torqued fixtures do not buckle or distort and provide an optimum thermal conductance. The fixtures simulating an actual spacecraft configuration suffered severe bowing and separating, which caused considerable degradation of conductance values.
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On the Effective Thermal Conductivity of Frost Considering Mass Diffusion and Eddy Convection
NASA Technical Reports Server (NTRS)
Kandula, Max
2010-01-01
A physical model for the effective thermal conductivity of water frost is proposed for application to the full range of frost density. The proposed model builds on the Zehner-Schlunder one-dimensional formulation for porous media appropriate for solid-to-fluid thermal conductivity ratios less than about 1000. By superposing the effects of mass diffusion and eddy convection on stagnant conduction in the fluid, the total effective thermal conductivity of frost is shown to be satisfactorily described. It is shown that the effects of vapor diffusion and eddy convection on the frost conductivity are of the same order. The results also point out that idealization of the frost structure by cylindrical inclusions offers a better representation of the effective conductivity of frost as compared to spherical inclusions. Satisfactory agreement between the theory and the measurements for the effective thermal conductivity of frost is demonstrated for a wide range of frost density and frost temperature.
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Characteristics of Sodium Polyacrylate/Nano-Sized Carbon Hydrogel for Biomedical Patch.
Park, Jong-Kyu; Seo, Sun-Kyo; Cho, Seungkwan; Kim, Han-Sung; Lee, Chi-Hwan
2018-03-01
Conductive hydrogels were prepared for biomedical patch in order to improve the electrical conductivity. Sodium polyacrylate and nano-sized carbon were mixed and fabricated by aqueous solution gelation process in various contents of nano-sized carbon with 0.1, 0.5, 1.0 and 2.0 wt%. Sodium polyacrylate/nano-sized carbon conductive hydrogels were investigated by molecular structure, surface morphology and electrical conductivity. The conductivity of the hydrogel/nano-sized carbon conductive hydrogel proved to be 10% higher than conductive hydrogel without nano-sized carbon. However, it was founded that conductive hydrogels with nano-sized carbon content from 0.5 up to 2.0 wt% were remarkably decreased. This may be due to the non-uniform distribution of nano-sized carbon, resulting from agglomerates of nano-sized carbon. The developed hydrogel is intended for use in the medical and cosmetic fields that is applicable to supply micro-current from device to human body.
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A Network Model for the Effective Thermal Conductivity of Rigid Fibrous Refractory Insulations
NASA Technical Reports Server (NTRS)
Marschall, Jochen; Cooper, D. M. (Technical Monitor)
1995-01-01
A procedure is described for computing the effective thermal conductivity of a rigid fibrous refractory insulation. The insulation is modeled as a 3-dimensional Cartesian network of thermal conductance. The values and volume distributions of the conductance are assigned to reflect the physical properties of the insulation, its constituent fibers, and any permeating gas. The effective thermal conductivity is computed by considering the simultaneous energy transport by solid conduction, gas conduction and radiation through a cubic volume of model insulation; thus the coupling between heat transfer modes is retained (within the simplifications inherent to the model), rather than suppressed by treating these heat transfer modes as independent. The model takes into account insulation composition, density and fiber anisotropy, as well as the geometric and material properties of the constituent fibers. A relatively good agreement, between calculated and experimentally derived thermal conductivity values, is obtained for a variety of rigid fibrous insulations.
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Wilcox, Russell B.
1991-01-01
A planar transparent light conducting means and an improved optically activated electrical switch made using the novel light conducting means are disclosed. The light conducting means further comprise light scattering means on one or more opposite planar surfaces thereof to transmit light from the light conducting means into adjacent media and reflective means on other surfaces of the light conducting means not containing the light scattering means. The optically activated electrical switch comprises at least two stacked photoconductive wafers, each having electrodes formed on both surfaces thereof, and separated by the planar transparent light conducting means. The light scattering means on the light conducting means face surfaces of the wafers not covered by the electrodes to transmit light from the light conducting means into the photoconductive wafers to uniformly illuminate and activate the switch.
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Hernandez, Maria Jose; Montes, Fernando; Ruiz, Federico; Lopez, Gustavo; Pita, Pilar
2016-01-01
Background and Aims Stomatal conductance has long been considered of key interest in the study of plant adaptation to water stress. The expected increase in extreme meteorological events under a climate change scenario may compromise survival in Eucalyptus globulus plantations established in south-western Spain. We investigated to what extent changes in stomatal conductance in response to high vapour pressure deficits and water shortage are mediated by hydraulic and chemical signals in greenhouse-grown E. globulus clones. Methods Rooted cuttings were grown in pots and submitted to two watering regimes. Stomatal conductance, shoot water potential, sap pH and hydraulic conductance were measured consecutively in each plant over 4 weeks under vapour pressure deficits ranging 0·42 to 2·25 kPa. Evapotranspiration, growth in leaf area and shoot biomass were also determined. Key Results There was a significant effect of both clone and watering regime in stomatal conductance and leaf-specific hydraulic conductance, but not in sap pH. Sap pH decreased as water potential and stomatal conductance decreased under increasing vapour pressure deficit. There was no significant relationship between stomatal conductance and leaf-specific hydraulic conductance. Stomata closure precluded shoot water potential from falling below −1·8 MPa. The percentage loss of hydraulic conductance ranged from 40 to 85 %. The highest and lowest leaf-specific hydraulic conductances were measured in clones from the same half-sib families. Water shortage reduced growth and evapotranspiration, decreases in evapotranspiration ranging from 14 to 32 % in the five clones tested. Conclusions Changes in sap pH seemed to be a response to changes in atmospheric conditions rather than soil water in the species. Stomata closed after a considerable amount of hydraulic conductance was lost, although intraspecific differences in leaf-specific hydraulic conductance suggest the possibility of selection for improved productivity under water-limiting conditions combined with high temperatures in the early stages of growth. PMID:27052343
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Atomistic simulations of highly conductive molecular transport junctions under realistic conditions
NASA Astrophysics Data System (ADS)
French, William R.; Iacovella, Christopher R.; Rungger, Ivan; Souza, Amaury Melo; Sanvito, Stefano; Cummings, Peter T.
2013-04-01
We report state-of-the-art atomistic simulations combined with high-fidelity conductance calculations to probe structure-conductance relationships in Au-benzenedithiolate (BDT)-Au junctions under elongation. Our results demonstrate that large increases in conductance are associated with the formation of monatomic chains (MACs) of Au atoms directly connected to BDT. An analysis of the electronic structure of the simulated junctions reveals that enhancement in the s-like states in Au MACs causes the increases in conductance. Other structures also result in increased conductance but are too short-lived to be detected in experiment, while MACs remain stable for long simulation times. Examinations of thermally evolved junctions with and without MACs show negligible overlap between conductance histograms, indicating that the increase in conductance is related to this unique structural change and not thermal fluctuation. These results, which provide an excellent explanation for a recently observed anomalous experimental result [Bruot et al., Nat. Nanotechnol., 2012, 7, 35-40], should aid in the development of mechanically responsive molecular electronic devices.We report state-of-the-art atomistic simulations combined with high-fidelity conductance calculations to probe structure-conductance relationships in Au-benzenedithiolate (BDT)-Au junctions under elongation. Our results demonstrate that large increases in conductance are associated with the formation of monatomic chains (MACs) of Au atoms directly connected to BDT. An analysis of the electronic structure of the simulated junctions reveals that enhancement in the s-like states in Au MACs causes the increases in conductance. Other structures also result in increased conductance but are too short-lived to be detected in experiment, while MACs remain stable for long simulation times. Examinations of thermally evolved junctions with and without MACs show negligible overlap between conductance histograms, indicating that the increase in conductance is related to this unique structural change and not thermal fluctuation. These results, which provide an excellent explanation for a recently observed anomalous experimental result [Bruot et al., Nat. Nanotechnol., 2012, 7, 35-40], should aid in the development of mechanically responsive molecular electronic devices. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr00459g
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NASA Astrophysics Data System (ADS)
Katsura, T.; Fei, H.; Koizumi, S.; Sakamoto, N.; Yurimoto, H.
2016-12-01
Although the water corporation has been considered to enhance the electrical conductivity of olivine by the proton conduction, the magnitude of the proton conduction is relatively small at asthenospheric temperatures because of its smaller activation energy than those of the small polaron and ionic conductions. However, the water incorporation could enhance the ionic conduction, because it should increase the defect density in the Mg sites. Since the ionic conductivity is proportional to the diffusivity, we have measured the self-diffusion coefficients of Mg in forsterite as a function of pressure, temperature and water content. We annealed fine-grained polycrystalline aggregates of forsterite with water contents up to 300 ppm, on whose polished plane a 25Mg-enriched Mg2SiO4 thin film was made, at pressures of 1 to 13 GPa and temperatures of 1100 to 1300 K. The lattice and grain-boundary diffusion coefficients were calculated simultaneously using profiles obtained by the depth analysis of SIMS. Experimental results gave the activation energy of 280 ± 30 and 360 ± 30 kJ/mol, activation volumes of 4.3 ± 0.3 and 3.9 ± 0.7 cm3/mol, and water content exponents of 1.2 ± 0.2 and 1.0 ± 0.1 for the lattice and grain-boundary diffusions, respectively. Using the ionic conduction data by Constable [2006] and Yoshino et al. [2009], and the water and pressure effects on Mg diffusivity in this study, the ionic conduction is found by 2 orders of magnitude higher than the small polaron and proton conductions under oceanic-asthenosphere conditions. Thus, the high conductivity of the oceanic asthenosphere will be governed by the water-enhanced ionic conduction. The negative pressure dependence of the Mg diffusivity and the gradual temperature increase in the asthenosphere will produce a conductivity maximum at the top of the asthenosphere. The high-conductivity layer at the top of the asthenosphere observed under very young oceanic plates can be attributed to this ionic conduction maximum.
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Hernandez, Maria Jose; Montes, Fernando; Ruiz, Federico; Lopez, Gustavo; Pita, Pilar
2016-05-01
Stomatal conductance has long been considered of key interest in the study of plant adaptation to water stress. The expected increase in extreme meteorological events under a climate change scenario may compromise survival in Eucalyptus globulus plantations established in south-western Spain. We investigated to what extent changes in stomatal conductance in response to high vapour pressure deficits and water shortage are mediated by hydraulic and chemical signals in greenhouse-grown E. globulus clones. Rooted cuttings were grown in pots and submitted to two watering regimes. Stomatal conductance, shoot water potential, sap pH and hydraulic conductance were measured consecutively in each plant over 4 weeks under vapour pressure deficits ranging 0·42 to 2·25 kPa. Evapotranspiration, growth in leaf area and shoot biomass were also determined. There was a significant effect of both clone and watering regime in stomatal conductance and leaf-specific hydraulic conductance, but not in sap pH. Sap pH decreased as water potential and stomatal conductance decreased under increasing vapour pressure deficit. There was no significant relationship between stomatal conductance and leaf-specific hydraulic conductance. Stomata closure precluded shoot water potential from falling below -1·8 MPa. The percentage loss of hydraulic conductance ranged from 40 to 85 %. The highest and lowest leaf-specific hydraulic conductances were measured in clones from the same half-sib families. Water shortage reduced growth and evapotranspiration, decreases in evapotranspiration ranging from 14 to 32 % in the five clones tested. Changes in sap pH seemed to be a response to changes in atmospheric conditions rather than soil water in the species. Stomata closed after a considerable amount of hydraulic conductance was lost, although intraspecific differences in leaf-specific hydraulic conductance suggest the possibility of selection for improved productivity under water-limiting conditions combined with high temperatures in the early stages of growth. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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Electrically conductive ceramic powders
NASA Astrophysics Data System (ADS)
Lu, Yanxia
1999-11-01
Electrically conductive ceramic powders were investigated in this project. There are three ways to produce those materials. The first is doping alkali metal into the titanium dioxides in an inert or reducing atmosphere. The second is reducing un-doped titanium dioxide, forming a non-stoichiometric composition in a hydrogen atmosphere. The third is to coat a conductive layer, reduced titanium dioxide, on an insulating core such as alumina. Highly conductive powders have been produced by all these processes. The conductivity of powder compacts ranged between 10-2 and 10° S/cm. A novel doping process was developed. All samples were doped by a solid-vapor reaction instead of a solid state reaction. Titanium dioxide was doped with alkali metals such as Na or Li in this study. The alkali metal atom contributes an electron to the host material (TiO2), which then creates Ti 3+ ion. The conductivity was enhanced by creating the donor level due to the presence of these Ti3+ ions. The conductivity of those alkali doped titanium oxides was dependent on the doping level and charge mobility. Non-stoichiometric titanium oxides were produced by reduction of titanium dioxide in a hydrogen atmosphere at 800°C to 1000°C for 2 to 6 hours. The reduced titanium oxides showed better stability with respect to conductivity at ambient condition when compared with the Na or Li doped samples. Conductive coatings were prepared by coating titanium precursors on insulating core materials like SiO2, Al2O3 or mica. The titania coating was made by hydrolysis of titanyl sulfate (TiOSO 4) followed by a reduction procedure to form reduced titanium oxide. The reduced titanium oxides are highly conductive. A uniform coating of titanium oxides on alumina cores was successfully produced. The conductivity of coated powder composites was a function of coating quantity and hydrolysis reaction temperature. The conductivity of the powder as a function of structure, composition, temperature, frequency and moisture was studied. Three classifications of structure were identified for alkali-doped titanium oxides: (1) Pure titanium dioxide phase with alkali ions located in interstitial positions. (2) The titanium bronze phases. (3) Alkali-doped titanium oxides. Highly conductive powders were obtained in the first and second classifications with conductivity of 10-2 to 10° S/cm. Materials in the third classification had poor conductivity below 10-3 S/cm. The conductivity of a powder was determined mainly by the grain conductivity and the grain contact conductivity. The present results of impedance spectroscopy suggested that the grain contact resistance was a major factor of the electrical resistance of the samples. The aging effect at different moisture conditions was also caused by an increase of the contact resistance. Both sodium-doped and reduced titanium oxides showed re-oxidation at elevated temperature (above 140°C) in air, which is most probably caused by oxidizing the Ti3+ ions under those conditions. Lithium doped titanium oxides did not show this re-oxidation at temperatures up to 200°C. Theoretical models were applied to describe the effects of porosity, contact configuration and grain surface on conductivity of powder compacts. Percolation theory was used in the present study to demonstrate the effect of mixtures of conductive and non-conductive powders, which is one of applications for conductive ceramic powders when they are used as filler materials in paper, paints or plastics.
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Wu, Johnny; Witkiewitz, Katie; McMahon, Robert J; Dodge, Kenneth A
2010-10-01
Conduct problems, substance use, and risky sexual behavior have been shown to coexist among adolescents, which may lead to significant health problems. The current study was designed to examine relations among these problem behaviors in a community sample of children at high risk for conduct disorder. A latent growth model of childhood conduct problems showed a decreasing trend from grades K to 5. During adolescence, four concurrent conduct problem and substance use trajectory classes were identified (high conduct problems and high substance use, increasing conduct problems and increasing substance use, minimal conduct problems and increasing substance use, and minimal conduct problems and minimal substance use) using a parallel process growth mixture model. Across all substances (tobacco, binge drinking, and marijuana use), higher levels of childhood conduct problems during kindergarten predicted a greater probability of classification into more problematic adolescent trajectory classes relative to less problematic classes. For tobacco and binge drinking models, increases in childhood conduct problems over time also predicted a greater probability of classification into more problematic classes. For all models, individuals classified into more problematic classes showed higher proportions of early sexual intercourse, infrequent condom use, receiving money for sexual services, and ever contracting an STD. Specifically, tobacco use and binge drinking during early adolescence predicted higher levels of sexual risk taking into late adolescence. Results highlight the importance of studying the conjoint relations among conduct problems, substance use, and risky sexual behavior in a unified model. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.
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Preparation, characterization and application of novel proton conducting ceramics
NASA Astrophysics Data System (ADS)
Wang, Siwei
Due to the immediate energy shortage and the requirement of environment protection nowadays, the efficient, effective and environmental friendly use of current energy sources is urgent. Energy conversion and storage is thus an important focus both for industry and academia. As one of the hydrogen energy related materials, proton conducting ceramics can be applied in solid oxide fuel cells and steam electrolysers, as well as high temperature hydrogen separation membranes and hydrogen sensors. For most of the practical applications, both high proton conductivity and chemical stability are desirable. However, the state-of-the-art proton conducting ceramics are facing great challenges in simultaneously fulfilling conductivity and stability requirements for practical applications. Consequently, understanding the properties for the proton conducting ceramics and developing novel materials that possess both high proton conductivity and enhanced chemical stability have both scientific and practical significances. The objective of this study is to develop novel proton conducting ceramics, either by evaluating the doping effects on the state-of-the-art simple perovskite structured barium cerates, or by investigating novel complex perovskite structured Ba3Ca1.18Nb1.82O 9-delta based proton conductors as potential proton conducting ceramics with improved proton conductivity and enhanced chemical stability. Different preparation methods were compared, and their influence on the structure, including the bulk and grain boundary environment has been investigated. In addition, the effects of microstructure on the electrical properties of the proton conducting ceramics have also been characterized. The solid oxide fuel cell application for the proton conducting ceramics performed as electrolyte membranes has been demonstrated.
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Kim, Hyun-Sik; Lee, Kyu Hyoung; Yoo, Joonyeon; Youn, Jehun; Roh, Jong Wook; Kim, Sang-Il; Kim, Sung Wng
2017-07-06
Cation substitutional doping is an effective approach to modifying the electronic and thermal transports in Bi₂Te₃-based thermoelectric alloys. Here we present a comprehensive analysis of the electrical and thermal conductivities of polycrystalline Pb-doped p-type bulk Bi 0.48 Sb 1.52 Te₃. Pb doping significantly increased the electrical conductivity up to ~2700 S/cm at x = 0.02 in Bi 0.48-x Pb x Sb 1.52 Te₃ due to the increase in hole carrier concentration. Even though the total thermal conductivity increased as Pb was added, due to the increased hole carrier concentration, the thermal conductivity was reduced by 14-22% if the contribution of the increased hole carrier concentration was excluded. To further understand the origin of reduction in the thermal conductivity, we first estimated the contribution of bipolar conduction to thermal conductivity from a two-parabolic band model, which is an extension of the single parabolic band model. Thereafter, the contribution of additional point defect scattering caused by Pb substitution (Pb in the cation site) was analyzed using the Debye-Callaway model. We found that Pb doping significantly suppressed both the bipolar thermal conduction and lattice thermal conductivity simultaneously, while the bipolar contribution to the total thermal conductivity reduction increased at high temperatures. At Pb doping of x = 0.02, the bipolar thermal conductivity decreased by ~30% from 0.47 W/mK to 0.33 W/mK at 480 K, which accounts for 70% of the total reduction.
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Kwon, O; Park, J
2006-11-01
This study examined the application of a Self Recovering Sustainable Layer (SRSL) as a landfill final cover. Low-conductivity layers in landfill covers are known to have problems associated with cracking as a result of the differential settlement or climatic changes. A SRSL is defined as a layer with chemical properties that reduces the increased hydraulic conductivity resulting from cracking by forming low-conductivity precipitates of chemicals contained in the layer. In this study, the formation of precipitates was confirmed using a batch test, spectroscopic analysis and mineralogical speciation tests. The possibility of secondary contamination due to the chemicals used for recovery was evaluated using a leaching test. A laboratory conductivity test was performed on a single layer composed of each chemical as well as on a 2-layer system. The recovery performance of the SRSL was estimated by developing artificial cracks in the specimens and observing the change in hydraulic conductivity as a function of time. In the laboratory conductivity test, the hydraulic conductivity of a 2-layer system as well as those of the individual layers that comprise the 2-layer system was estimated. In addition sodium ash was found to enhance the reduction in conductivity. A significant increase in conductivity was observed after the cracks developed but this was reduced with time, which indicated that the SRSL has a proper recovering performance. In conclusion, a SRSL can be used as a landfill final cover that could maintain low-conductivity even after the serious damages due to settlement.
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Kim, Hyun-sik; Lee, Kyu Hyoung; Yoo, Joonyeon; Youn, Jehun; Roh, Jong Wook; Kim, Sang-il; Kim, Sung Wng
2017-01-01
Cation substitutional doping is an effective approach to modifying the electronic and thermal transports in Bi2Te3-based thermoelectric alloys. Here we present a comprehensive analysis of the electrical and thermal conductivities of polycrystalline Pb-doped p-type bulk Bi0.48Sb1.52Te3. Pb doping significantly increased the electrical conductivity up to ~2700 S/cm at x = 0.02 in Bi0.48-xPbxSb1.52Te3 due to the increase in hole carrier concentration. Even though the total thermal conductivity increased as Pb was added, due to the increased hole carrier concentration, the thermal conductivity was reduced by 14–22% if the contribution of the increased hole carrier concentration was excluded. To further understand the origin of reduction in the thermal conductivity, we first estimated the contribution of bipolar conduction to thermal conductivity from a two-parabolic band model, which is an extension of the single parabolic band model. Thereafter, the contribution of additional point defect scattering caused by Pb substitution (Pb in the cation site) was analyzed using the Debye–Callaway model. We found that Pb doping significantly suppressed both the bipolar thermal conduction and lattice thermal conductivity simultaneously, while the bipolar contribution to the total thermal conductivity reduction increased at high temperatures. At Pb doping of x = 0.02, the bipolar thermal conductivity decreased by ~30% from 0.47 W/mK to 0.33 W/mK at 480 K, which accounts for 70% of the total reduction. PMID:28773118
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Align and random electrospun mat of PEDOT:PSS and PEDOT:PSS/RGO
NASA Astrophysics Data System (ADS)
Sarabi, Ghazale Asghari; Latifi, Masoud; Bagherzadeh, Roohollah
2018-01-01
In this research work we fabricated two ultrafine conductive nanofibrous layers to investigate the materilas composition and their properties for the preparation of supercapacitor materials application. In first layer, a polymer and a conductive polymer were used and second layer was a composition of polymer, conductive polymer and carbon-base material. In both cases align and randomized mat of conductive nanofibers were fabricated using electrospinning set up. Conductive poly (3,4-ethylenedioxythiophene)/ polystyrene sulfonate (PEDOT:PSS) nanofibers were electrospun by dissolving fiber-forming polymer and polyvinyl alcohol (PVA) in an aqueous dispersion of PEDOT:PSS. The effect of addition of reduced graphene oxide (RGO) was considered for nanocomposite layer. The ultrafine conductive polymer fibers and conductive nanocomposite fibrous materials were also fabricated using an electrospinning process. A fixed collector and a rotating drum were used for random and align nanofibers production, respectively. The resulted fibers were characterized and analyzed by SEM, FTIR and two-point probe conductivity test. The average diameter of nanofibers measured by ImageJ software indicated that the average fiber diameter for first layer was 100 nm and for nanocomposite layer was about 85 nm. The presence of PEDOT:PSS and RGO in the nanofibers was confirmed by FT-IR spectroscopy. The conductivity of align and random layers was characterized. The conductivity of PEDOT:PSS nanofibers showed higher enhancement by addition of RGO in aqueous dispersion. The obtained results showed that alignment of fibrous materials can be considered as an engineering tool for tuning the conductivity of fibrous materials for many different applications such as supercapacitors, conductive and transparent materials.
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Electrical conductivity of high-purity germanium crystals at low temperature
NASA Astrophysics Data System (ADS)
Yang, Gang; Kooi, Kyler; Wang, Guojian; Mei, Hao; Li, Yangyang; Mei, Dongming
2018-05-01
The temperature dependence of electrical conductivity of single-crystal and polycrystalline high-purity germanium (HPGe) samples has been investigated in the temperature range from 7 to 100 K. The conductivity versus inverse of temperature curves for three single-crystal samples consist of two distinct temperature ranges: a high-temperature range where the conductivity increases to a maximum with decreasing temperature, and a low-temperature range where the conductivity continues decreasing slowly with decreasing temperature. In contrast, the conductivity versus inverse of temperature curves for three polycrystalline samples, in addition to a high- and a low-temperature range where a similar conductive behavior is shown, have a medium-temperature range where the conductivity decreases dramatically with decreasing temperature. The turning point temperature ({Tm}) which corresponds to the maximum values of the conductivity on the conductivity versus inverse of temperature curves are higher for the polycrystalline samples than for the single-crystal samples. Additionally, the net carrier concentrations of all samples have been calculated based on measured conductivity in the whole measurement temperature range. The calculated results show that the ionized carrier concentration increases with increasing temperature due to thermal excitation, but it reaches saturation around 40 K for the single-crystal samples and 70 K for the polycrystalline samples. All these differences between the single-crystal samples and the polycrystalline samples could be attributed to trapping and scattering effects of the grain boundaries on the charge carriers. The relevant physical models have been proposed to explain these differences in the conductive behaviors between two kinds of samples.
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Zhang, Yumei; Wang, Chunxue; Zhao, Xingquan; Chen, Hongyan; Han, Zaizhu; Wang, Yongjun
2010-09-01
In contrast with disorders of comprehension and spontaneous expression, conduction aphasia is characterized by poor repetition, which is a hallmark of the syndrome. There are many theories on the repetition impairment of conduction aphasia. The disconnection theory suggests that a damaged in the arcuate fasciculus, which connects Broca's and Wernicke's area, is the cause of conduction aphasia. In this study, we examined the disconnection theory. We enrolled ten individuals with conduction aphasia and ten volunteers, and analysed their arcuate fasciculus using diffusion tensor imaging (DTI) and obtained fractional anisotropy (FA) values. Then, the results of the left hemisphere were compared with those of the right hemisphere, and the results of the conduction aphasia cases were compared with those of the volunteers. There were significant differences in the FA values between the left and right hemispheres of volunteers and conduction cases. In volunteers, there was an increase in fiber in the left hemisphere compared with the right hemisphere, whereas there was an increase in fiber in the right hemisphere compared with the left hemisphere in conduction aphasia patients. The results of diffusion tensor tractography suggested that the configuration of the arcuate fasciculus was different between conduction aphasia patients and volunteers, suggesting that there was damage to the arcuate fasciculus of conduction aphasia cases. The damage seen in the arcuate fasciculus of conduction aphasia cases in this study supports the Wernicke-Geschwind disconnection theory. A disconnection between Broca's area and Wernicke's area is likely to be one mechanism of conduction aphasia repetition impairment.
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DC and AC conductivity properties of bovine dentine hydroxyapatite (BDHA)
NASA Astrophysics Data System (ADS)
Dumludag, F.; Gunduz, O.; Kılıc, O.; Ekren, N.; Kalkandelen, C.; Ozbek, B.; Oktar, F. N.
2017-12-01
Bovine dentine bio-waste may be used as a potential natural source of hydroxyapatite (BDHA), thus extraction of bovine dentin hydroxyapatite (BDHA) from bio-waste is significantly important to fabricate in a simple, economically and environmentally preferable. DC and AC conductivity properties of BDHA were investigated depending on sintering temperature (1000ºC - 1300°C) in air and vacuum (<10-2 mbar) ambient at room temperature. DC conductivity measurements performed between -1 and 1 V. AC conductivity measurements performed in the frequency range of 40 Hz - 100 kHz. DC conductivity results showed that dc conductivity values of the BDHA decrease with increasing sintering temperature in air ambient. It is not observed remarkable/systematic behavior for ac conductivity depending on sintering temperature.
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Modelling heat conduction in polycrystalline hexagonal boron-nitride films
Mortazavi, Bohayra; Pereira, Luiz Felipe C.; Jiang, Jin-Wu; Rabczuk, Timon
2015-01-01
We conducted extensive molecular dynamics simulations to investigate the thermal conductivity of polycrystalline hexagonal boron-nitride (h-BN) films. To this aim, we constructed large atomistic models of polycrystalline h-BN sheets with random and uniform grain configuration. By performing equilibrium molecular dynamics (EMD) simulations, we investigated the influence of the average grain size on the thermal conductivity of polycrystalline h-BN films at various temperatures. Using the EMD results, we constructed finite element models of polycrystalline h-BN sheets to probe the thermal conductivity of samples with larger grain sizes. Our multiscale investigations not only provide a general viewpoint regarding the heat conduction in h-BN films but also propose that polycrystalline h-BN sheets present high thermal conductivity comparable to monocrystalline sheets. PMID:26286820
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Method and apparatus for casting conductive and semiconductive materials
Ciszek, Theodore F.
1986-01-01
A method and apparatus is disclosed for casting conductive and semiconduce materials. The apparatus includes a plurality of conductive members arranged to define a container-like area having a desired cross-sectional shape. A portion or all of the conductive or semiconductive material which is to be cast is introduced into the container-like area. A means is provided for inducing the flow of an electrical current in each of the conductive members, which currents act collectively to induce a current flow in the material. The induced current flow through the conductive members is in a direction substantially opposite to the induced current flow in the material so that the material is repelled from the conductive members during the casting process.
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Enhancing electron transport in molecular wires by insertion of a ferrocene center.
Sun, Yan-Yan; Peng, Zheng-Lian; Hou, Rong; Liang, Jing-Hong; Zheng, Ju-Fang; Zhou, Xiao-Yi; Zhou, Xiao-Shun; Jin, Shan; Niu, Zhen-Jiang; Mao, Bing-Wei
2014-02-14
We have determined the conductance of alkane-linked ferrocene molecules with carboxylic acid anchoring groups using the STM break junction technique, and three sets of conductance values were found, i.e. high conductance (HC), medium conductance (MC) and low conductance (LC) values. The enhancing effect of the incorporated ferrocene on the electron transport in saturated alkane molecular wires is demonstrated by the increased conductance of the ferrocene molecules, attributed to the reduction of the tunneling barrier and the HOMO-LUMO gap induced by the insertion of ferrocene. Furthermore, the electron-withdrawing carbonyl group on the unconjugated backbone has little or no influence on single-molecule conductance. The current work provides a feasible approach for the design of high-performance molecular wires.
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Effect of Eutectic Concentration on Conductivity in PEO:LiX Based Solid Polymer Electrolytes
NASA Astrophysics Data System (ADS)
Zhan, Pengfei; Ganapatibhotla, Lalitha; Maranas, Janna
Polyethylene oxide (PEO) and lithium salt based solid polymer electrolytes (SPEs) have been widely proposed as a substitution for the liquid electrolyte in Li-ion batteries. As salt concentration varies, these systems demonstrate rich phase behavior. Conductivity as a function of salt concentration has been measured for decades and various concentration dependences have been observed. A PEO:LiX mixture can have one or two conductivity maximums, while some mixtures with salt of high ionic strength will have higher conductivity as the salt concentration decrease. The factors that affect the conductivity are specific for each sample. The universal factor that affects conductivity is still not clear. In this work, we measured the conductivity of a series of PEO:LiX mixtures and statistical analysis shows conductivity is affected by the concentration difference from the eutectic concentration (Δc). The correlation with Δc is stronger than the correlation with glass transition temperature. We believe that at the eutectic concentration, during the solidification process, unique structures can form which aid conduction. Currently at Dow Chemical.
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Han, Joong Tark; Kim, Byung Kuk; Woo, Jong Seok; Jang, Jeong In; Cho, Joon Young; Jeong, Hee Jin; Jeong, Seung Yol; Seo, Seon Hee; Lee, Geon-Woong
2017-03-01
Directly printed superhydrophobic surfaces containing conducting nanomaterials can be used for a wide range of applications in terms of nonwetting, anisotropic wetting, and electrical conductivity. Here, we demonstrated that direct-printable and flexible superhydrophobic surfaces were fabricated on flexible substrates via with an ultrafacile and scalable screen printing with carbon nanotube (CNT)-based conducting pastes. A polydimethylsiloxane (PDMS)-polyethylene glycol (PEG) copolymer was used as an additive for conducting pastes to realize the printability of the conducting paste as well as the hydrophobicity of the printed surface. The screen-printed conducting surfaces showed a high water contact angle (WCA) (>150°) and low contact angle hysteresis (WCA < 5°) at 25 wt % PDMS-PEG copolymer in the paste, and they have an electrical conductivity of over 1000 S m -1 . Patterned superhydrophobic surfaces also showed sticky superhydrophobic characteristics and were used to transport water droplets. Moreover, fabricated films on metal meshes were used for an oil/water separation filter, and liquid evaporation behavior was investigated on the superhydrophobic and conductive thin-film heaters by applying direct current voltage to the film.
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Enhancement in ionic conductivity on solid polymer electrolytes containing large conducting species
DOE Office of Scientific and Technical Information (OSTI.GOV)
Praveen, D.; Damle, Ramakrishna
2016-05-23
Solid Polymer Electrolytes (SPEs) lack better conducting properties at ambient temperatures. Various methods to enhance their ionic conductivity like irradiation with swift heavy ions, γ-rays, swift electrons and quenching at low temperature etc., have been explored in the literature. Among these, one of the oldest methods is incorporation of different conducting species into the polymer matrix and/or addition of nano-sized inert particles into SPEs. Various new salts like LiBr, Mg(ClO{sub 4}){sub 2}, NH{sub 4}I etc., have already been tried in the past with some success. Also various nanoparticles like Al{sub 2}O{sub 3}, TiO{sub 2} etc., have been tried in themore » past. In this article, we have investigated an SPE containing Rubidium as a conducting species. Rubidium has a larger ionic size compared to lithium and sodium ions which have been investigated in the recent past. In the present article, we have investigated the conductivity of large sized conducting species and shown the enhancement in the ionic conductivity by addition of nano-sized inert particles.« less
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Stringaris, Argyris; Lewis, Glyn; Maughan, Barbara
2014-07-01
Pathways from early-life conduct problems to young adult depression remain poorly understood. To test developmental pathways from early-life conduct problems to depression at age 18. Data (n = 3542) came from the Avon Longitudinal Study of Parents and Children (ALSPAC). Previously derived conduct problem trajectories (ages 4-13 years) were used to examine associations with depression from ages 10 to 18 years, and the role of early childhood factors as potential confounders. Over 43% of young adults with depression in the ALSPAC cohort had a history of child or adolescent conduct problems, yielding a population attributable fraction of 0.15 (95% CI 0.08-0.22). The association between conduct problems and depression at age 18 was considerable even after adjusting for prior depression (odds ratio 1.55, 95% CI 1.24-1.94). Early-onset persistent conduct problems carried the highest risk for later depression. Irritability characterised depression for those with a history of conduct problems. Early-life conduct problems are robustly associated with later depressive disorder and may be useful targets for early intervention. Royal College of Psychiatrists.
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Electrical conductivity of electrolytes applicable to natural waters from 0 to 100 degrees C
McCleskey, R. Blaine
2011-01-01
The electrical conductivities of 34 electrolyte solutions found in natural waters ranging from (10-4 to 1) molkg-1 in concentration and from (5 to 90) °C have been determined. High-quality electrical conductivity data for numerous electrolytes exist in the scientific literature, but the data do not span the concentration or temperature ranges of many electrolytes in natural waters. Methods for calculating the electrical conductivities of natural waters have incorporated these data from the literature, and as a result these methods cannot be used to reliably calculate the electrical conductivity over a large enough range of temperature and concentration. For the single-electrolyte solutions, empirical equations were developed that relate electrical conductivity to temperature and molality. For the 942 molar conductivity determinations for single electrolytes from this study, the mean relative difference between the calculated and measured values was 0.1 %. The calculated molar conductivity was compared to literature data, and the mean relative difference for 1978 measurements was 0.2 %. These data provide an improved basis for calculating electrical conductivity for most natural waters.
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Analysis of effective thermal conductivity of fibrous materials
NASA Technical Reports Server (NTRS)
Futschik, Michael W.; Witte, Larry C.
1993-01-01
The objective of this research is to gain a better understanding of the various mechanisms of heat transfer through fibrous materials and to gain insight into how fill-gas pressure influences the effective thermal conductivity. By way of first principles and some empiricism, two mathematical models are constructed to correlate experimental data. The data are obtained from a test series measuring the effective thermal conductivity of Nomex using a two-sided guarded hot-plate heater apparatus. Tests are conducted for certain mean temperatures and fill-gases over a range of pressures varying from vacuum to atmospheric conditions. The models are then evaluated to determine their effectiveness in representing the effective thermal conductivity of a fibrous material. The models presented herein predict the effective thermal conductivity of Nomex extremely well. Since the influence of gas conduction is determined to be the most influential component in predicting the effective thermal conductivity of a fibrous material, an improved representation of gas conduction is developed. Finally, some recommendations for extension to other random-oriented fiber materials are made concerning the usefulness of each model depending on their advantages and disadvantages.
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NASA Astrophysics Data System (ADS)
Hui, KeShi; Dai, LiDong; Li, HePing; Hu, HaiYing; Jiang, JianJun; Sun, WenQing; Zhang, Hui
2017-03-01
The electrical conductivity of pyroxene andesite was in situ measured under conditions of 1.0-2.0 GPa and 673-1073 K using a YJ-3000t multi-anvil press and Solartron-1260 Impedance/Gain-phase analyzer. Experimental results indicate that the electrical conductivities of pyroxene andesite increase with increasing temperature, and the electrical conductivities decrease with the rise of pressure, and the relationship between electrical conductivity ( σ) and temperature ( T) conforms to an Arrhenius relation within a given pressure and temperature range. When temperature rises up to 873-923 K, the electrical conductivities of pyroxene andesite abruptly increase, and the activation enthalpy increases at this range, which demonstrates that pyroxene andesite starts to dehydrate. By the virtue of the activation enthalpy (0.35-0.42 eV) and the activation volume (-6.75 ± 1.67 cm3/mole) which characterizes the electrical properties of sample after dehydration, we consider that the conduction mechanism is the small polaron conduction before and after dehydration, and that the rise of carrier concentration is the most important reason of increased electrical conductivity.
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Electronic Conductivity of Doped-Lanthanum Gallate Electrolytes
NASA Astrophysics Data System (ADS)
Yamaji, Katsuhiko; Xiong, Yue Ping; Kishimoto, Haruo; Horita, Teruhisa; Sakai, Natsuko; Brito, Manuel E.; Yokokawa, Harumi
Electronic conductivity of doped lanthanum gallate electrolytes were determined by using a Hebb-Wagner type polarization cell. Electronic conductivity of cobalt-doped, La0.8Sr0.2Ga0.8Mg0.15Co0.5O3-δ (LSGMC), and non cobalt-doped, La0.8Sr0.2Ga0.8Mg0.2O2.8 (LSGM8282), were measured as a function of oxygen partial pressures. The electronic conductivity of LSGM8282 showed a linear dependence on p(O2)1/4 in the higher p(O2) region, which is attributed to the electronic hole conductivity. The electronic conductivity of LSGMC showed a linear dependence on p(O2)1/6 in the higher p(O2) region. LSGMC has higher electronic conductivity than LSGM, and the conductivity was not clearly changed with temperatures between 600 and 800 °C. In lower p(O2) region, the electronic conductivity data have poor reproducibility and did not show any dependence on p(O2) because of the degradation of the electrolytes in severe reducing atmospheres.
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Thermal flux limited electron Kapitza conductance in copper-niobium multilayers
Cheaito, Ramez; Hattar, Khalid Mikhiel; Gaskins, John T.; ...
2015-03-05
The interplay between the contributions of electron thermal flux and interface scattering to the Kapitza conductance across metal-metal interfaces through measurements of thermal conductivity of copper-niobium multilayers was studied. Thermal conductivities of copper-niobium multilayer films of period thicknesses ranging from 5.4 to 96.2 nm and sample thicknesses ranging from 962 to 2677 nm are measured by time-domain thermoreflectance over a range of temperatures from 78 to 500 K. The Kapitza conductances between the Cu and Nb interfaces in multilayer films are determined from the thermal conductivities using a series resistor model and are in good agreement with the electron diffusemore » mismatch model. The results for the thermal boundary conductance between Cu and Nb are compared to literature values for the thermal boundary conductance across Al-Cu and Pd-Ir interfaces, and demonstrate that the interface conductance in metallic systems is dictated by the temperature derivative of the electron energy flux in the metallic layers, rather than electron mean free path or scattering processes at the interface.« less
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Stringaris, Argyris; Lewis, Glyn; Maughan, Barbara
2014-01-01
Background Pathways from early-life conduct problems to young adult depression remain poorly understood. Aims To test developmental pathways from early-life conduct problems to depression at age 18. Method Data (n = 3542) came from the Avon Longitudinal Study of Parents and Children (ALSPAC). Previously derived conduct problem trajectories (ages 4-13 years) were used to examine associations with depression from ages 10 to 18 years, and the role of early childhood factors as potential confounders. Results Over 43% of young adults with depression in the ALSPAC cohort had a history of child or adolescent conduct problems, yielding a population attributable fraction of 0.15 (95% CI 0.08-0.22). The association between conduct problems and depression at age 18 was considerable even after adjusting for prior depression (odds ratio 1.55, 95% CI 1.24-1.94). Early-onset persistent conduct problems carried the highest risk for later depression. Irritability characterised depression for those with a history of conduct problems. Conclusions Early-life conduct problems are robustly associated with later depressive disorder and may be useful targets for early intervention. PMID:24764545
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NASA Technical Reports Server (NTRS)
Zhu, Dong-Ming; Miller, Robert A.
2004-01-01
The development of low conductivity and high temperature capable thermal barrier coatings requires advanced testing techniques that can accurately and effectively evaluate coating thermal conductivity under future high-performance and low-emission engine heat-flux conditions. In this paper, a unique steady-state CO2 laser (wavelength 10.6 microns) heat-flux approach is described for determining the thermal conductivity and conductivity deduced cyclic durability of ceramic thermal and environmental barrier coating systems at very high temperatures (up to 1700 C) under large thermal gradients. The thermal conductivity behavior of advanced thermal and environmental barrier coatings for metallic and Si-based ceramic matrix composite (CMC) component applications has also been investigated using the laser conductivity approach. The relationships between the lattice and radiation conductivities as a function of heat flux and thermal gradient at high temperatures have been examined for the ceramic coating systems. The steady-state laser heat-flux conductivity approach has been demonstrated as a viable means for the development and life prediction of advanced thermal barrier coatings for future turbine engine applications.
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ERIC Educational Resources Information Center
Tanaka, John; Suib, Steven L.
1984-01-01
Discusses the properties of surface-conducting glass and the chemical nature of surface-conducting stannic (tin) oxide. Also provides the procedures necessary for the preparation of surface-conducting stannic oxide films on glass substrates. The experiment is suitable for the advanced inorganic chemistry laboratory. (JN)
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Electrical condition monitoring method for polymers
Watkins, Jr., Kenneth S.; Morris, Shelby J [Hampton, VA; Masakowski, Daniel D [Worcester, MA; Wong, Ching Ping [Duluth, GA; Luo, Shijian [Boise, ID
2008-08-19
An electrical condition monitoring method utilizes measurement of electrical resistivity of an age sensor made of a conductive matrix or composite disposed in a polymeric structure such as an electrical cable. The conductive matrix comprises a base polymer and conductive filler. The method includes communicating the resistivity to a measuring instrument and correlating resistivity of the conductive matrix of the polymeric structure with resistivity of an accelerated-aged conductive composite.
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The Measurement of Electrical Conductivity in Detonating Condensed Explosives
1993-03-01
in the light of our existing understanding. DETONATION CONDUCTION MODELS Various models of conduction have been considered during the course of these...reduction, shock induced conduction in the reaction products, and conduction in coagulated carbon behind the reaction zone. The first model , due to...results below show. The second model was proposed by Griem. 3 For relative simplicity, he assumed that the reaction zone could be represented by a
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Electrical screening procedure for solid ionic conductors
NASA Technical Reports Server (NTRS)
Kautz, H. E.; Singer, J.; Fielder, W. L.; Fordyce, J. S.
1973-01-01
An electrical screening method has been developed for preliminary evaluation of polycrystalline specimens of candidates for use as solid ionic conductive electrolytes in batteries. The procedure measures dielectric loss and capacitance, from which are calculated an ac conductivity attributed provisionally to ions and an activation energy for that conductivity. Electronic conductivity is directly measured. The screening procedure applied to sodium beta-alumina yielded acceptable values for conductivity and activation energy.
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The Polyanilines: A Novel Class of Conducting Polymers
1992-06-19
yield pos~ive and negative solitons. Other conducting polymers are briefly discussed. The polyanilines , a large class of versatile conducting polymers...Speia TEC-9NTlCAL REPORT NO.: 1992-35 - "THE POLYANILINES : A NOVEL CLASS OF CONDUCTING POLYMERS" by A.G. MacDiarmid Accepted for Publication in...34The Polyanilines : A Novel Class of Conducting Polymers," Proceed. Nobel Symposium 81, in Cpniuaated Polymers and Related Materials: The Interconnection
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Khomkin, A. L., E-mail: alhomkin@mail.ru; Shumikhin, A. S.
The conductivity of metal vapors at the critical point and near it has been considered. The liquid-metal conductivity originates in this region. The thermodynamic parameters of the critical point, the density of conduction electrons, and the conductivities of various metal vapors have been calculated within the unified approach. It has been proposed to consider the conductivity at the critical point—critical conductivity—as the fourth critical parameter in addition to the density, temperature, and pressure.
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Fabrication of glass microspheres with conducting surfaces
Elsholz, William E.
1984-01-01
A method for making hollow glass microspheres with conducting surfaces by adding a conducting vapor to a region of the glass fabrication furnace. As droplets or particles of glass forming material pass through multiple zones of different temperature in a glass fabrication furnace, and are transformed into hollow glass microspheres, the microspheres pass through a region of conducting vapor, forming a conducting coating on the surface of the microspheres.
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Fabrication of glass microspheres with conducting surfaces
Elsholz, W.E.
1982-09-30
A method for making hollow glass microspheres with conducting surfaces by adding a conducting vapor to a region of the glass fabrication furnace. As droplets or particles of glass forming material pass through multiple zones of different temperature in a glass fabrication furnace, and are transformed into hollow glass microspheres, the microspheres pass through a region of conducting vapor, forming a conducting coating on the surface of the microspheres.
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Maintainable substrate carrier for electroplating
Chen, Chen-An [Milpitas, CA; Abas, Emmanuel Chua [Laguna, PH; Divino, Edmundo Anida [Cavite, PH; Ermita, Jake Randal G [Laguna, PH; Capulong, Jose Francisco S [Laguna, PH; Castillo, Arnold Villamor [Batangas, PH; Ma,; Xiaobing, Diana [Saratoga, CA
2012-07-17
One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The carrier includes a non-conductive carrier body on which the substrates are placed and conductive lines embedded within the carrier body. A plurality of conductive clip attachment parts are attached in a permanent manner to the conductive lines embedded within the carrier body. A plurality of contact clips are attached in a removable manner to the clip attachment parts. The contact clips hold the substrates in place and conductively connecting the substrates with the conductive lines. Other embodiments, aspects and features are also disclosed.
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Thermal properties of granulated materials.
NASA Technical Reports Server (NTRS)
Wechsler, A. E.; Glaser, P. E.; Fountain, J. A.
1972-01-01
Review of the thermophysical properties of granular materials or silicates believed to simulate the lunar surface layer. Emphasis is placed on thermal conductivity data and the effects of material and environmental variables on the thermal conductivity. There are three basic mechanisms of heat transfer in particulate materials: conduction by the gas contained in the void spaces between the particles; conduction within the solid particles and across the interparticle contacts; and thermal radiation within the particles, across the void spaces between particle surfaces, and between void spaces themselves. Gas and solid conduction, thermal radiation, and the interaction between conduction and radiation are considered.
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Maintainable substrate carrier for electroplating
Chen, Chen-An; Abas, Emmanuel Chua; Divino, Edmundo Anida; Ermita, Jake Randal G.; Capulong, Jose Francisco S.; Castillo, Arnold Villamor; Ma, Diana Xiaobing
2016-08-02
One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The carrier includes a non-conductive carrier body on which the substrates are placed and conductive lines embedded within the carrier body. A plurality of conductive clip attachment parts are attached in a permanent manner to the conductive lines embedded within the carrier body. A plurality of contact clips are attached in a removable manner to the clip attachment parts. The contact clips hold the substrates in place and conductively connecting the substrates with the conductive lines. Other embodiments, aspects and features are also disclosed.
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Proton conduction in metal-organic frameworks and related modularly built porous solids.
Yoon, Minyoung; Suh, Kyungwon; Natarajan, Srinivasan; Kim, Kimoon
2013-03-04
Proton-conducting materials are an important component of fuel cells. Development of new types of proton-conducting materials is one of the most important issues in fuel-cell technology. Herein, we present newly developed proton-conducting materials, modularly built porous solids, including coordination polymers (CPs) or metal-organic frameworks (MOFs). The designable and tunable nature of the porous materials allows for fast development in this research field. Design and synthesis of the new types of proton-conducting materials and their unique proton-conduction properties are discussed. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Conductance bistability of gold nanowires at room temperature
NASA Astrophysics Data System (ADS)
Kiguchi, Manabu; Konishi, Tatsuya; Murakoshi, Kei
2006-03-01
Quantized conductance behavior of gold nanowires was studied under electrochemical potential control. We fabricated 1-nm -long monoatomic wires in solution at room temperature. Electrochemical potential significantly affected the stability of the monoatomic wire and fractional conductance peak occurrence in the conductance histogram. We revealed that the hydrogen adsorption on gold monoatomic wires was a decisive factor of the fractional peak, which was originated from the dynamic structural transition between two bistable states of the monoatomic wire showing the unit and the fractional values of the conductance. We could tune the stability of these bistable states to make the fractional conductance state preferable.
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Thermal conductivity of austenitic stainless steel, SRM 735, from 5 to 280 K
NASA Technical Reports Server (NTRS)
Hust, J. G.; Sparks, L. L.
1972-01-01
Thermal conductivity and electrical resistivity measurements were conducted on two lots of an austenitic stainless steel. Electrical resistivity measurements were performed on the second lot, both before and after the material was hot-swaged and reannealed to a size 1/10 the original diameter. These measurements indicate that this steel can be swaged and reannealed without an appreciable change in thermal conductivity. Electrical resistivity measurements as well as direct thermal conductivity measurements on several specimens from both lots indicate a material variability in these lots of less than 1% in thermal conductivity.
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Electrically conductive composite material
Clough, R.L.; Sylwester, A.P.
1989-05-23
An electrically conductive composite material is disclosed which comprises a conductive open-celled, low density, microcellular carbon foam filled with a non-conductive polymer or resin. The composite material is prepared in a two-step process consisting of first preparing the microcellular carbon foam from a carbonizable polymer or copolymer using a phase separation process, then filling the carbon foam with the desired non-conductive polymer or resin. The electrically conductive composites of the present invention has a uniform and consistent pattern of filler distribution, and as a result is superior over prior art materials when used in battery components, electrodes, and the like. 2 figs.
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Electrically conductive composite material
Clough, R.L.; Sylwester, A.P.
1988-06-20
An electrically conductive composite material is disclosed which comprises a conductive open-celled, low density, microcellular carbon foam filled with a non-conductive polymer or resin. The composite material is prepared in a two-step process consisting of first preparing the microcellular carbon foam from a carbonizable polymer or copolymer using a phase separation process, then filling the carbon foam with the desired non-conductive polymer or resin. The electrically conductive composites of the present invention has a uniform and consistent pattern of filler distribution, and as a result is superior over prior art materials when used in battery components, electrodes, and the like. 2 figs.
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Electrically conductive composite material
Clough, Roger L.; Sylwester, Alan P.
1989-01-01
An electrically conductive composite material is disclosed which comprises a conductive open-celled, low density, microcellular carbon foam filled with a non-conductive polymer or resin. The composite material is prepared in a two-step process consisting of first preparing the microcellular carbon foam from a carbonizable polymer or copolymer using a phase separation process, then filling the carbon foam with the desired non-conductive polymer or resin. The electrically conductive composites of the present invention has a uniform and consistant pattern of filler distribution, and as a result is superior over prior art materials when used in battery components, electrodes, and the like.
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Measurements of the microwave conductivity of the organic superconductor ET2 (IAuI)
NASA Astrophysics Data System (ADS)
Tanner, D. B.; Jacobsen, C. S.; Williams, J. M.; Wang, H. H.
The microwave conductivity of ET2(IAuI), which is superconducting below 4 K, has been measured between 20 and 300 K. The measurements were done by cavity perturbation at 35 GHz for electric field along the highly conducting direction. The samples were in the skin-depth limit. The room temperature conductivity is quite low, approximately 6 mu/cm. With a decrease in temperature the conductivity increases as T sup -2 reaching nearly 900 mu/cm at 20 K. These values are rather close to extrapolations of the frequency-dependent conductivity determined from far-infrared experiments.
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Significantly enhanced thermal conductivity of indium arsenide nanowires via sulfur passivation.
Xiong, Yucheng; Tang, Hao; Wang, Xiaomeng; Zhao, Yang; Fu, Qiang; Yang, Juekuan; Xu, Dongyan
2017-10-16
In this work, we experimentally investigated the effect of sulfur passivation on thermal transport in indium arsenide (InAs) nanowires. Our measurement results show that thermal conductivity can be enhanced by a ratio up to 159% by sulfur passivation. Current-voltage (I-V) measurements were performed on both unpassivated and S-passivated InAs nanowires to understand the mechanism of thermal conductivity enhancement. We observed a remarkable improvement in electrical conductivity upon sulfur passivation and a significant contribution of electrons to thermal conductivity, which account for the enhanced thermal conductivity of the S-passivated InAs nanowires.
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Double anisotropic electrically conductive flexible Janus-typed membranes.
Li, Xiaobing; Ma, Qianli; Tian, Jiao; Xi, Xue; Li, Dan; Dong, Xiangting; Yu, Wensheng; Wang, Xinlu; Wang, Jinxian; Liu, Guixia
2017-12-07
Novel type III anisotropic conductive films (ACFs), namely flexible Janus-typed membranes, were proposed, designed and fabricated for the first time. Flexible Janus-typed membranes composed of ordered Janus nanobelts were constructed by electrospinning, which simultaneously possess fluorescence and double electrically conductive anisotropy. For the fabrication of the Janus-typed membrane, Janus nanobelts comprising a conductive side and an insulative-fluorescent side were primarily fabricated, and then the Janus nanobelts are arranged into parallel arrays using an aluminum rotary drum as the collector to obtain a single anisotropically conductive film. Subsequently, a secondary electrospinning process was applied to the as-prepared single anisotropically conductive films to acquire the final Janus-typed membrane. For this Janus-typed membrane, namely its left-to-right structure, anisotropic electrical conduction synchronously exists on both sides, and furthermore, the two electrically conductive directions are perpendicular. By modulating the amount of Eu(BA) 3 phen complex and conducting polyaniline (PANI), the characteristics and intensity of the fluorescence-electricity dual-function in the membrane can be tuned. The high integration of this peculiar Janus-typed membrane with simultaneous double electrically conductive anisotropy-fluorescent dual-functionality is successfully realized in this study. This design philosophy and preparative technique will provide support for the design and construction of new types of special nanostructures with multi-functionality.
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Clinical guideline on bone conduction implants.
Lavilla Martín de Valmaseda, María José; Cavalle Garrido, Laura; Huarte Irujo, Alicia; Núñez Batalla, Faustino; Manrique Rodriguez, Manuel; Ramos Macías, Ángel; de Paula Vernetta, Carlos; Gil-Carcedo Sañudo, Elisa; Lassaleta, Luis; Sánchez-Cuadrado, Isabel; Espinosa Sánchez, Juan Manuel; Batuecas Caletrio, Ángel; Cenjor Español, Carlos
2018-04-13
During the last decade there have been multiple and relevant advances in conduction and mixed hearing loss treatment. These advances and the appearance of new devices have extended the indications for bone-conduction implants. The Scientific Committee of Audiology of the Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello SEORL-CCC (Spanish Society of Otolaryngology and Head and Neck Surgery), together with the Otology and Otoneurology Committees, have undertaken a review of the current state of bone-conduction devices with updated information, to provide a clinical guideline on bone-conduction implants for otorhinolaryngology specialists, health professionals, health authorities and society in general. This clinical guideline on bone-conduction implants contains information on the following: 1) Definition and description of bone-conduction devices; 2) Current and upcoming indications for bone conduction devices: Magnetic resonance compatibility; 3) Organization requirements for a bone-conduction implant programme. The purpose of this guideline is to describe the different bone-conduction implants, their characteristics and their indications, and to provide coordinated instructions for all the above-mentioned agents for decision making within their specific work areas. Copyright © 2018 Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. Publicado por Elsevier España, S.L.U. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Lebedev, Oleg V.; N.S. Enikolopov Institute of Synthetic Polymer Materials of RAS, Profsoyuznaya st., Moscow, 117393; Kechek’yan, Alexander S.
Electrically conductive oriented polymer nano-composites of different compositions, based on the reactor powder of ultra-high-molecular-weight polyethylene (UHMWPE) with a special morphology, filled with particles of nanostructured graphite (NG), multi-walled carbon nanotubes (MWCNTs), and electrically conductive carbon black (CB), were investigated. Polymer composites were obtained via compaction of the mechanical mixture of the polymer and filler powder, followed by uniaxial deformation of the material under homogeneous shear (HS) conditions (all of the processing stages were conducted at room temperature). Resulted composites possess a high tensile strength, high level of the electrical conductivity and low percolation threshold, owing it to the formationmore » of the segregated conductive structure, The influence of the type of nanosized carbon filler, degree of the deformation under HS condition, temperature and etc. on the electrical conductivity and mechanical properties of strengthened conductive composites oriented under homogeneous shear conditions was investigated. Changes in the electrical conductivity of oriented composite materials during reversible “tension–shrinkage” cycles along the orientation axis direction were studied. A theoretical approach, describing the process of transformation of the conductive system as a response on polymer phase deformation and volume change, was proposed, based on the data received from the analysis of the conductivity behavior during the uniaxial deformation and thermal treatment of composites.« less
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Maslowsky, Julie; Schulenberg, John E
2013-11-01
Substance use is a major contributor to morbidity and mortality among American adolescents. Conduct problems and depressive symptoms have each been found to be associated with adolescent substance use. Although they are highly comorbid, the role of the interaction of conduct problems and depressive symptoms in substance use is not clear. In national samples of 8th-, 10th-, and 12th-grade students from the Monitoring the Future study, latent moderated structural equation modeling was used to estimate the association of conduct problems, depressive symptoms, and their interaction to the use of alcohol (including binge drinking), cigarettes, and marijuana. Moderation by age and sex was tested. The interaction of conduct problems with depressive symptoms was a strong predictor of substance use, particularly among younger adolescents. With few exceptions, adolescents with high levels of both conduct problems and depressive symptoms used substances most frequently. Conduct problems were a strong positive predictor of substance use, and depressive symptoms were a weak positive predictor. Whereas conduct problems are often thought to be a primary predictor of substance use, this study revealed that depressive symptoms potentiate the relation of conduct problems to substance use. Therefore, substance use prevention efforts should target both depressive symptoms and conduct problems.
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Thermal Conductivity Measurement of Anisotropic Biological Tissue In Vitro
NASA Astrophysics Data System (ADS)
Yue, Kai; Cheng, Liang; Yang, Lina; Jin, Bitao; Zhang, Xinxin
2017-06-01
The accurate determination of the thermal conductivity of biological tissues has implications on the success of cryosurgical/hyperthermia treatments. In light of the evident anisotropy in some biological tissues, a new modified stepwise transient method was proposed to simultaneously measure the transverse and longitudinal thermal conductivities of anisotropic biological tissues. The physical and mathematical models were established, and the analytical solution was derived. Sensitivity analysis and experimental simulation were performed to determine the feasibility and measurement accuracy of simultaneously measuring the transverse and longitudinal thermal conductivities. The experimental system was set up, and its measurement accuracy was verified by measuring the thermal conductivity of a reference standard material. The thermal conductivities of the pork tenderloin and bovine muscles were measured using the traditional 1D and proposed methods, respectively, at different temperatures. Results indicate that the thermal conductivities of the bovine muscle are lower than those of the pork tenderloin muscle, whereas the bovine muscle was determined to exhibit stronger anisotropy than the pork tenderloin muscle. Moreover, the longitudinal thermal conductivity is larger than the transverse thermal conductivity for the two tissues and all thermal conductivities increase with the increase in temperature. Compared with the traditional 1D method, results obtained by the proposed method are slightly higher although the relative deviation is below 5 %.
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Zhang, Xiaoguang; McGuire, Michael A.; Chen, Yong P.; ...
2016-03-08
Topological insulators, with characteristic topological surface states, have emerged as a new state of matter with rich potentials for both fundamental physics and device applications. However, the experimental detection of the surface transport has been hampered by the unavoidable extrinsic conductivity associated with the bulk crystals. Here we show that a four-probe transport spectroscopy in a multi-probe scanning tunneling microscopy system can be used to differentiate conductivities from the surface states and the coexisting bulk states in topological insulators. We derive a scaling relation of measured resistance with respect to varying inter-probe spacing for two interconnected conduction channels, which allowsmore » quantitative determination of conductivities from both channels. Using this method, we demonstrate the separation of 2D and 3D conduction in topological insulators by comparing the conductance scaling of Bi 2Se 3, Bi 2Te 2Se, and Sb-doped Bi 2Se 3 with that of a pure 2D conductance of graphene on SiC substrate. We also report the 2D conductance enhancement due to the surface doping effect in topological insulators. This technique can be applied to reveal 2D to 3D crossover of conductance in other complex systems.« less
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Electrical conductivity modeling in fractal non-saturated porous media
NASA Astrophysics Data System (ADS)
Wei, W.; Cai, J.; Hu, X.; Han, Q.
2016-12-01
The variety of electrical conductivity in non-saturated conditions is important to study electric conduction in natural sedimentary rocks. The electrical conductivity in completely saturated porous media is a porosity-function representing the complex connected behavior of single conducting phases (pore fluid). For partially saturated conditions, the electrical conductivity becomes even more complicated since the connectedness of pore. Archie's second law is an empirical electrical conductivity-porosity and -saturation model that has been used to predict the formation factor of non-saturated porous rock. However, the physical interpretation of its parameters, e.g., the cementation exponent m and the saturation exponent n, remains questionable. On basis of our previous work, we combine the pore-solid fractal (PSF) model to build an electrical conductivity model in non-saturated porous media. Our theoretical porosity- and saturation-dependent models contain endmember properties, such as fluid electrical conductivities, pore fractal dimension and tortuosity fractal dimension (representing the complex degree of electrical flowing path). We find the presented model with non-saturation-dependent electrical conductivity datasets indicate excellent match between theory and experiments. This means the value of pore fractal dimension and tortuosity fractal dimension change from medium to medium and depends not only on geometrical properties of pore structure but also characteristics of electrical current flowing in the non-saturated porous media.
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High temperature conductivity of potassium-beta(double prime)-alumina
NASA Technical Reports Server (NTRS)
Williams, R. M.; Jeffries-Nakamura, B.; Underwood, M. L.; Ryan, M. A.; O'Connor, D.; Kikkert, S.
1992-01-01
Potassium beta(double prime)-alumina (BDPA) single crystals have been reported by several groups to leave higher ionic conductivity than sodium BDPA crystals at room temperature, and similar conductivities are obtained at temperatures up to 600-700 K. Potassium BDPA ceramics have been reported to have significantly poorer conductivities than those of sodium BDPA ceramics, but conductivity measurements at temperatures above 625 K have not been reported. In this study, K(+)-BDPA ceramics were prepared from Na(+)-BDPA ceramic using a modified version of the exchange reaction with KCl vapor reported by Crosbie and Tennenhouse (1982), and the conductivity has been measured in K vapor at temperatures up to 1223 K, using the method of Cole et al. (1979). The results indicate reasonable agreement with earlier data on K(+)-BDPA ceramic measured in a liquid K cell, but show that the K(+)-BDPA ceramic's conductivity approaches that of Na(+)-BDPA ceramic at higher temperatures, being within a factor of four at 700 K and 60 percent of the conductivity of Na(+)-BDPA at T over 1000 K. Both four-probe dc conductivity and four probe ac impedance measurements were used to characterize the conductivity. A rather abrupt change in the grain boundary resistance suggesting a possible phase change in the intergranular material, potassium aluminate, is seen in the ac impedance behavior.
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Phonon thermal conductivity of monolayer MoS{sub 2}
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Xiaonan; Tabarraei, Alireza, E-mail: atabarra@uncc.edu
We use nonequilibrium molecular dynamics modeling using Stillinger–Weber interatomic potential to investigate the thermal properties of monolayer molybdenum disulfide (MoS{sub 2}) nanoribbons. We study the impact of factors such as length, edge chirality, monovacancies, and uniaxial stretching on the thermal conductivity of MoS{sub 2} nanoribbons. Our results show that longer ribbons have a higher thermal conductivity, and the thermal conductivity of infinitely long zigzag and armchair MoS{sub 2} nanoribbons is, respectively, 54 W/mK and 33 W/mK. This is significantly lower than the thermal conductivity of some other graphene-like two-dimensional materials such as graphene and boron nitride. While the presence of molybdenum ormore » sulfur vacancies reduces the thermal conductivity of ribbons, molybdenum vacancies have a more deteriorating effect on thermal conductivities. We also have studied the impact of uniaxial stretching on the thermal conductivity of MoS{sub 2} nanoribbons. The results show that in contrast to three dimensional materials, thermal conductivity of MoS{sub 2} is fairly insensitive to stretching. We have used the phonon dispersion curves and group velocities to investigate the mechanism of this unexpected behavior. Our results show that tensile strain does not alter the phonon dispersion curves and hence the thermal conductivity does not change.« less
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NASA Astrophysics Data System (ADS)
Okuda, Yoshiyuki; Ohta, Kenji; Yagi, Takashi; Sinmyo, Ryosuke; Wakamatsu, Tatsuya; Hirose, Kei; Ohishi, Yasuo
2017-09-01
Bridgmanite (Bdg), iron (Fe)- and aluminum (Al)-bearing magnesium silicate perovskite is the most abundant mineral in the Earth's lower mantle. Thus, its thermal conductivity governs the lower mantle thermal conductivity that critically controls the thermo-chemical evolution of both the core and the lower mantle. While there is extensive research for the lattice thermal conductivity of MgSiO3 Bdg, the effects of Fe and Al incorporation on its lattice thermal conduction are still controversial. Here we report the lattice thermal conductivity of Mg0.832Fe0.209Al0.060Si0.916O3 Bdg measured up to 142 GPa at 300 K using the pulsed light heating thermoreflectance technique in a diamond anvil cell. The results show that the lattice thermal conductivity of Bdg is 25.5 ± 2.2 W/m/K at 135 GPa and 300 K, which is 19% lower than that of Fe and Al-free Bdg at identical conditions. Considering the temperature effect on the lattice conductivity and the contribution of radiative thermal conductivity, the total thermal conductivity of Fe and Al-bearing Bdg does not change very much with temperature at 135 GPa, and could be higher than that of post-perovskite with identical chemical composition.
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Through-plane conductivities of membranes for nonaqueous redox flow batteries
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, Travis Mark; Small, Leo J.; Pratt, III, Harry D.
In this study, nonaqueous redox flow batteries (RFB) leverage nonaqueous solvents to enable higher operating voltages compared to their aqueous counterparts. Most commercial components for flow batteries, however, are designed for aqueous use. One critical component, the ion-selective membrane, provides ionic conductance between electrodes while preventing crossover of electroactive species. Here we evaluate the area-specific conductances and through-plane conductivities of commercially available microporous separators (Celgard 2400, 2500) and anion exchange membranes (Neosepta AFX, Neosepta AHA, Fumasep FAP-450, Fumasep FAP-PK) soaked in acetonitrile, propylene carbonate, or two imidazolium-based ionic liquids. Fumasep membranes combined with acetonitrile-based electrolyte solutions provided the highest conductancemore » values and conductivities by far. When tested in ionic liquids, all anion exchange membranes displayed conductivities greater than those of the Celgard microporous separators, though the separators’ decreased thickness-enabled conductances on par with the most conductive anion exchange membranes. Ionic conductivity is not the only consideration when choosing an anion exchange membrane; testing of FAP-450 and FAP-PK membranes in a nonaqueous RFB demonstrated that the increased mechanical stability of PEEK-supported FAP-PK minimized swelling, in turn decreasing solvent mediated crossover and enabling greater electrochemical yields (40% vs. 4%) and Coulombic efficiencies (94% vs. 90%) compared to the unsupported, higher conductance FAP-450.« less
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Through-plane conductivities of membranes for nonaqueous redox flow batteries
Anderson, Travis Mark; Small, Leo J.; Pratt, III, Harry D.; ...
2015-08-13
In this study, nonaqueous redox flow batteries (RFB) leverage nonaqueous solvents to enable higher operating voltages compared to their aqueous counterparts. Most commercial components for flow batteries, however, are designed for aqueous use. One critical component, the ion-selective membrane, provides ionic conductance between electrodes while preventing crossover of electroactive species. Here we evaluate the area-specific conductances and through-plane conductivities of commercially available microporous separators (Celgard 2400, 2500) and anion exchange membranes (Neosepta AFX, Neosepta AHA, Fumasep FAP-450, Fumasep FAP-PK) soaked in acetonitrile, propylene carbonate, or two imidazolium-based ionic liquids. Fumasep membranes combined with acetonitrile-based electrolyte solutions provided the highest conductancemore » values and conductivities by far. When tested in ionic liquids, all anion exchange membranes displayed conductivities greater than those of the Celgard microporous separators, though the separators’ decreased thickness-enabled conductances on par with the most conductive anion exchange membranes. Ionic conductivity is not the only consideration when choosing an anion exchange membrane; testing of FAP-450 and FAP-PK membranes in a nonaqueous RFB demonstrated that the increased mechanical stability of PEEK-supported FAP-PK minimized swelling, in turn decreasing solvent mediated crossover and enabling greater electrochemical yields (40% vs. 4%) and Coulombic efficiencies (94% vs. 90%) compared to the unsupported, higher conductance FAP-450.« less
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Reduced DIDS-sensitive chloride conductance in Ae1-/- mouse erythrocytes
Alper, Seth L.; Vandorpe, David H.; Peters, Luanne L.; Brugnara, Carlo
2008-01-01
The resting membrane potential of the human erythrocyte is largely determined by a constitutive Cl- conductance ∼100-fold greater than the resting cation conductance. The 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid (DIDS)-sensitive electroneutral Cl- transport mediated by the human erythroid Cl-/HCO3- exchanger, AE1 (SLC4A1, band 3) is ≥10,000-fold greater than can be accounted for by the Cl- conductance of the red cell. The molecular identities of conductive anion pathways across the red cell membrane remain poorly defined. We have examined red cell Cl- conductance in the Ae1-/- mouse as a genetic test of the hypothesis that Ae1 mediates DIDS-sensitive Cl- conductance in mouse red cells. We report here that wildtype mouse red cell membrane potential resembles that of human red cells in the predominance of its Cl- conductance. We show with four technical approaches that the DIDS-sensitive component of erythroid Cl- conductance is reduced or absent from Ae1-/- red cells. These results are consistent with the hypothesis that the Ae1 anion exchanger polypeptide can operate infrequently in a conductive mode. However, the fragile red cell membrane of the Ae1-/- mouse red cell exhibits reduced abundance or loss of multiple polypeptides. Thus, loss of one or more distinct, DIDS-sensitive anion channel polypeptide(s) from the Ae1-/- red cell membrane cannot be ruled out as an explanation for the reduced DIDS-sensitive anion conductance. PMID:18329299
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Bounds on strong field magneto-transport in three-dimensional composites
NASA Astrophysics Data System (ADS)
Briane, Marc; Milton, Graeme W.
2011-10-01
This paper deals with bounds satisfied by the effective non-symmetric conductivity of three-dimensional composites in the presence of a strong magnetic field. On the one hand, it is shown that for general composites the antisymmetric part of the effective conductivity cannot be bounded solely in terms of the antisymmetric part of the local conductivity, contrary to the columnar case studied by Briane and Milton [SIAM J. Appl. Math. 70(8), 3272-3286 (2010), 10.1137/100798090]. Thus a suitable rank-two laminate, the conductivity of which has a bounded antisymmetric part together with a high-contrast symmetric part, may generate an arbitrarily large antisymmetric part of the effective conductivity. On the other hand, bounds are provided which show that the antisymmetric part of the effective conductivity must go to zero if the upper bound on the antisymmetric part of the local conductivity goes to zero, and the symmetric part of the local conductivity remains bounded below and above. Elementary bounds on the effective moduli are derived assuming the local conductivity and the effective conductivity have transverse isotropy in the plane orthogonal to the magnetic field. New Hashin-Shtrikman type bounds for two-phase three-dimensional composites with a non-symmetric conductivity are provided under geometric isotropy of the microstructure. The derivation of the bounds is based on a particular variational principle symmetrizing the problem, and the use of Y-tensors involving the averages of the fields in each phase.
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Universal Behavior of Quantum Spin Liquid and Optical Conductivity in the Insulator Herbertsmithite
NASA Astrophysics Data System (ADS)
Shaginyan, V. R.; Msezane, A. Z.; Stephanovich, V. A.; Popov, K. G.; Japaridze, G. S.
2018-04-01
We analyze optical conductivity with the goal to demonstrate experimental manifestation of a new state of matter, the so-called fermion condensate. Fermion condensates are realized in quantum spin liquids, exhibiting typical behavior of heavy-fermion metals. Measurements of the low-frequency optical conductivity collected on the geometrically frustrated insulator herbertsmithite provide important experimental evidence of the nature of its quantum spin liquid composed of spinons. To analyze recent measurements of the herbertsmithite optical conductivity at different temperatures, we employ a model of strongly correlated quantum spin liquid located near the fermion condensation phase transition. Our theoretical analysis of the optical conductivity allows us to expose the physical mechanism of its temperature dependence. We also predict a dependence of the optical conductivity on a magnetic field. We consider an experimental manifestation (optical conductivity) of a new state of matter (so-called fermion condensate) realized in quantum spin liquids, for, in many ways, they exhibit typical behavior of heavy-fermion metals. Measurements of the low-frequency optical conductivity collected on the geometrically frustrated insulator herbertsmithite produce important experimental evidence of the nature of its quantum spin liquid composed of spinons. To analyze recent measurements of the herbertsmithite optical conductivity at different temperatures, we employ a model of a strongly correlated quantum spin liquid located near the fermion condensation phase transition. Our theoretical analysis of the optical conductivity allows us to reveal the physical mechanism of its temperature dependence. We also predict a dependence of the optical conductivity on a magnetic field.
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Enhanced ionic conductivity of AgI nanowires/AAO composites fabricated by a simple approach.
Liu, Li-Feng; Lee, Seung-Woo; Li, Jing-Bo; Alexe, Marin; Rao, Guang-Hui; Zhou, Wei-Ya; Lee, Jae-Jong; Lee, Woo; Gösele, Ulrich
2008-12-10
AgI nanowires/anodic aluminum oxide (AgI NWs/AAO) composites have been fabricated by a simple approach, which involves the thermal melting of AgI powders on the surface of the AAO membrane, followed by the infiltration of the molten AgI inside the nanochannels. As-prepared AgI nanowires have corrugated outer surfaces and are polycrystalline according to scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations. X-ray diffraction (XRD) shows that a considerable amount of 7H polytype AgI exists in the composites, which is supposed to arise from the interfacial interactions between the embedded AgI and the alumina. AC conductivity measurements for the AgI nanowires/AAO composites exhibit a notable conductivity enhancement by three orders of magnitude at room temperature compared with that of pristine bulk AgI. Furthermore, a large conductivity hysteresis and abnormal conductivity transitions were observed in the temperature-dependent conductivity measurements, from which an ionic conductivity as high as 8.0 × 10(2) Ω(-1) cm(-1) was obtained at around 70 °C upon cooling. The differential scanning calorimetry (DSC) result demonstrates a similar phase transition behavior as that found in the AC conductivity measurements. The enhanced ionic conductivity, as well as the abnormal phase transitions, can be explained in terms of the existence of the highly conducting 7H polytype AgI and the formation of well-defined conduction paths in the composites.
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Visual ecology and potassium conductances of insect photoreceptors.
Frolov, Roman; Immonen, Esa-Ville; Weckström, Matti
2016-04-01
Voltage-activated potassium channels (Kv channels) in the microvillar photoreceptors of arthropods are responsible for repolarization and regulation of photoreceptor signaling bandwidth. On the basis of analyzing Kv channels in dipteran flies, it was suggested that diurnal, rapidly flying insects predominantly express sustained K(+) conductances, whereas crepuscular and nocturnally active animals exhibit strongly inactivating Kv conductances. The latter was suggested to function for minimizing cellular energy consumption. In this study we further explore the evolutionary adaptations of the photoreceptor channelome to visual ecology and behavior by comparing K(+) conductances in 15 phylogenetically diverse insects, using patch-clamp recordings from dissociated ommatidia. We show that rapid diurnal flyers such as the blowfly (Calliphora vicina) and the honeybee (Apis mellifera) express relatively large noninactivating Kv conductances, conforming to the earlier hypothesis in Diptera. Nocturnal and/or slow-moving species do not in general exhibit stronger Kv conductance inactivation in the physiological membrane voltage range, but the photoreceptors in species that are known to rely more on vision behaviorally had higher densities of sustained Kv conductances than photoreceptors of less visually guided species. No statistically significant trends related to visual performance could be identified for the rapidly inactivating Kv conductances. Counterintuitively, strong negative correlations were observed between photoreceptor capacitance and specific membrane conductance for both sustained and inactivating fractions of Kv conductance, suggesting insignificant evolutionary pressure to offset negative effects of high capacitance on membrane filtering with increased conductance. Copyright © 2016 the American Physiological Society.
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NASA Astrophysics Data System (ADS)
Tavakoli, Mahmoud; Rocha, Rui; Osorio, Luis; Almeida, Miguel; de Almeida, Anibal; Ramachandran, Vivek; Tabatabai, Arya; Lu, Tong; Majidi, Carmel
2017-03-01
Carbon doped PDMS (cPDMS), has been used as a conductive polymer for stretchable electronics. Compared to liquid metals, cPDMS is low cost and is easier to process or to print with an additive manufacturing process. However, changes on the conductance of the carbon based conductive PDMS (cPDMS) were observed over time, in particular after integration of cPDMS and the insulating polymer. In this article we investigate the process parameters that lead to improved stability over conductance of the cPDMS over time. Slight modifications to the fabrication process parameters were conducted and changes on the conductance of the samples for each method were monitored. Results suggested that change of the conductance happens mostly after integration of a pre-polymer over a cured cPDMS, and not after integration of the cPDMS over a cured insulating polymer. We show that such changes can be eliminated by adjusting the integration priority between the conductive and insulating polymers, by selecting the right curing temperature, changing the concentration of the carbon particles and the thickness of the conductive traces, and when possible by changing the insulating polymer material. In this way, we obtained important conclusions regarding the effect of these parameters on the change of the conductance over time, that should be considered for additive manufacturing of soft electronics. Also, we show that these changes can be possibly due to the diffusion from PDMS into cPDMS.
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Liu, L J; Schlesinger, M
2015-09-07
A correct description of the hydraulic conductivity is essential for determining the actual tumor interstitial fluid pressure (TIFP) distribution. Traditionally, it has been assumed that the hydraulic conductivities both in a tumor and normal tissue are constant, and that a tumor has a much larger interstitial hydraulic conductivity than normal tissue. The abrupt transition of the hydraulic conductivity at the tumor surface leads to non-physical results (the hydraulic conductivity and the slope of the TIFP are not continuous at tumor surface). For the sake of simplicity and the need to represent reality, we focus our analysis on avascular or poorly vascularized tumors, which have a necrosis that is mostly in the center and vascularization that is mostly on the periphery. We suggest that there is an intermediary region between the tumor surface and normal tissue. Through this region, the interstitium (including the structure and composition of solid components and interstitial fluid) transitions from tumor to normal tissue. This process also causes the hydraulic conductivity to do the same. We introduce a continuous variation of the hydraulic conductivity, and show that the interstitial hydraulic conductivity in the intermediary region should be monotonically increasing up to the value of hydraulic conductivity in the normal tissue in order for the model to correspond to the actual TIFP distribution. The value of the hydraulic conductivity at the tumor surface should be the lowest in value. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Effect of bone conduction transducer placement on distortion product otoacoustic emissions
NASA Astrophysics Data System (ADS)
Hazelbaker, Julie L.
The purpose of this study was to develop a technique to determine the magnitude of bone conducted sound in the cochlea when stimuli are delivered from three different locations on the head. Distortion product otoacoustic emissions (DPOAE) at 1000 and 2000 Hz were used as tools to determine cochlear response to stimuli introduced via air conduction and bone conduction in three subjects. The bone conduction transducer was moved to three head locations (ipsilateral mastoid, contralateral mastoid and forehead). The intensity of the emissions elicited was compared. The differences in DPOAE magnitude created by varying the location of the bone conduction transducer were compared with behavioral threshold differences with the same transducers at the same locations. It was assumed that results of behavioral measures would provide a prediction of the relationship between air and bone conducted DPOAE. However, in the current study, this was not the case. Behavioral bone conduction threshold data did not predict differences in DPOAE at different bone conduction transducer locations. This was a somewhat surprising result and should be considered further in future studies examining the properties of DPOAE elicited by bone conduction. Additionally, a wide band noise masker was introduced to the non-test ear when bone conducted stimuli were introduced to make DPOAE and behavioral test conditions as similar as possible. No great suppression effects were noted across subjects for either frequency. This was likely due to the shape and intensity of the contralateral masked used.
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Code of Federal Regulations, 2012 CFR
2012-01-01
... hearing to be conducted by telephone or audio-visual telecommunication; (10) Require each party to provide... prior to any deposition to be conducted by telephone or audio-visual telecommunication; (11) Require that any hearing to be conducted by telephone or audio-visual telecommunication be conducted at...
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Code of Federal Regulations, 2011 CFR
2011-01-01
... hearing to be conducted by telephone or audio-visual telecommunication; (10) Require each party to provide... prior to any deposition to be conducted by telephone or audio-visual telecommunication; (11) Require that any hearing to be conducted by telephone or audio-visual telecommunication be conducted at...
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The Workshop on Conductive Polymers: Final Report
DOE R&D Accomplishments Database
1985-10-01
Reports are made by groups on: polyacetylene, polyphenylene, polyaniline, and related systems; molecular, crystallographic, and defect structures in conducting polymers; heterocyclic polymers; synthesis of new and improved conducting polymers; future applications possibilities for conducting polymers; and challenges for improved understanding of properties. (DLC)
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NASA Astrophysics Data System (ADS)
Fuji-ta, K.; Katsura, T.; Tainosho, Y.
2004-04-01
We have developed a technique to measure electrical conductivity of crustal rocks with relatively low conductivity and complicated mineral components in order to compare with results given by magneto-telluric (MT) measurements. A granulite from Hidaka metamorphic belt (HMB) in Hokkaido, Japan at high temperature and pressure conditions was obtained. The granulite sample was ground and sintered under the conditions similar to those of mid- to lower crust. We have observed smooth and reversible change of conductivity with temperature up to about 900 K at 1 GPa. The results were consistent with the electrical conductivity structures suggested by the MT data analysis. Considering pore fluid conduction mechanism or the role of accessory minerals in the rock, the mechanisms of electrical conductivity paths in dry or basic rocks should be reconsidered.
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Ultrahigh Ionic Conduction in Water-Stable Close-Packed Metal-Carbonate Frameworks.
Manna, Biplab; Desai, Aamod V; Illathvalappil, Rajith; Gupta, Kriti; Sen, Arunabha; Kurungot, Sreekumar; Ghosh, Sujit K
2017-08-21
Utilization of the robust metal-carbonate backbone in a series of water-stable, anionic frameworks has been harnessed for the function of highly efficient solid-state ion-conduction. The compact organization of hydrophilic guest ions facilitates water-assisted ion-conduction in all the compounds. The dense packing of the compounds imparts high ion-conducting ability and minimizes the possibility of fuel crossover, making this approach promising for design and development of compounds as potential components of energy devices. This work presents the first report of evaluating ion-conduction in a purely metal-carbonate framework, which exhibits high ion-conductivity on the order of 10 -2 S cm -1 along with very low activation energy, which is comparable to highly conducting well-known crystalline coordination polymers or commercialized organic polymers like Nafion.
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Stretchable Conductive Composites from Cu-Ag Nanowire Felt.
Catenacci, Matthew J; Reyes, Christopher; Cruz, Mutya A; Wiley, Benjamin J
2018-04-24
Materials that retain a high conductivity under strain are essential for wearable electronics. This article describes a conductive, stretchable composite consisting of a Cu-Ag core-shell nanowire felt infiltrated with a silicone elastomer. This composite exhibits a retention of conductivity under strain that is superior to any composite with a conductivity greater than 1000 S cm -1 . This work also shows how the mechanical properties, conductivity, and deformation mechanism of the composite changes as a function of the stiffness of the silicone matrix. The retention of conductivity under strain was found to decrease as the Young's modulus of the matrix increased. This was attributed to void formation as a result of debonding between the nanowire felt and the elastomer. The nanowire composite was also patterned to create serpentine circuits with a stretchability of 300%.
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Fabrication of Conductive Macroporous Structures Through Nano-phase Separation Method
NASA Astrophysics Data System (ADS)
Kim, Soohyun; Lee, Hyunjung
2018-03-01
Thermoelectric power generation performance is characterized on the basis of the figure of merit, which tends to be high in thermoelectric materials with high electrical conductivity and low thermal conductivity. Porous structures cause phonon scattering, which decreases thermal conductivity. In this study, we fabricated porous structures for thermoelectric devices via nano-phase separation of silica particles from a polyacrylonitrile (PAN) matrix via a sol-gel process. The porosity was determined by control of silica particle size with various the mixing ratio of tetraethylorthosilicate as the precursor of silica particles to PAN. High electrical conductivity was maintained by subsequent carbonization of the PAN matrix in spited of a high porosity. As the results, the conductive porous structures having porosity from 13.9 to 83.3 (%) was successfully fabricated, keeping their electrical conductivities.
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Extreme low thermal conductivity in nanoscale 3D Si phononic crystal with spherical pores.
Yang, Lina; Yang, Nuo; Li, Baowen
2014-01-01
In this work, we propose a nanoscale three-dimensional (3D) Si phononic crystal (PnC) with spherical pores, which can reduce the thermal conductivity of bulk Si by a factor up to 10,000 times at room temperature. Thermal conductivity of Si PnCs depends on the porosity, for example, the thermal conductivity of Si PnCs with porosity 50% is 300 times smaller than that of bulk Si. The phonon participation ratio spectra demonstrate that more phonons are localized as the porosity increases. The thermal conductivity is insensitive to the temperature changes from room temperature to 1100 K. The extreme-low thermal conductivity could lead to a larger value of ZT than unity as the periodic structure affects very little the electric conductivity.
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Novel polymeric LIT and divalent cation fast ion conducting materials
NASA Astrophysics Data System (ADS)
Angell, C. A.
Solid state energy devices require a component which conducts electricity by ionic migration. The conductivity of this element of the system must be very high. Four types of materials show the promise to provide the necessary conductivity characteristics, while offering other desirable features such as the ability to distort in shape under mechanical stresses: (1) crystalline; (2) plastic crystal; (3) inorganic glassy; and (4) polymer salt solutions. This document reports on the following materials: lead halide-containing fast ion conducting glasses (LiF-PbF2-Al(PO3)3), mixed ionic electronic conduction (Na2O-V2O5-TeO2), alpha relaxation in ionic glasses, glass transition in P2O2, and conductivity transition between all-halide and all-oxide glasses.
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Oxygen-modulated quantum conductance for ultrathin HfO 2 -based memristive switching devices
Zhong, Xiaoliang; Rungger, Ivan; Zapol, Peter; ...
2016-10-24
Memristive switching devices, candidates for resistive random access memory technology, have been shown to switch off through a progression of states with quantized conductance and subsequent noninteger conductance (in terms of conductance quantum G 0). We have performed calculations based on density functional theory to model the switching process for a Pt-HfO 2-Pt structure, involving the movement of one or two oxygen atoms. Oxygen atoms moving within a conductive oxygen vacancy filament act as tunneling barriers, and partition the filament into weakly coupled quantum wells. We show that the low-bias conductance decreases exponentially when one oxygen atom moves away frommore » interface. In conclusion, our results demonstrate the high sensitivity of the device conductance to the position of oxygen atoms.« less
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Oxygen-modulated quantum conductance for ultrathin HfO 2 -based memristive switching devices
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhong, Xiaoliang; Rungger, Ivan; Zapol, Peter
Memristive switching devices, candidates for resistive random access memory technology, have been shown to switch off through a progression of states with quantized conductance and subsequent noninteger conductance (in terms of conductance quantum G 0). We have performed calculations based on density functional theory to model the switching process for a Pt-HfO 2-Pt structure, involving the movement of one or two oxygen atoms. Oxygen atoms moving within a conductive oxygen vacancy filament act as tunneling barriers, and partition the filament into weakly coupled quantum wells. We show that the low-bias conductance decreases exponentially when one oxygen atom moves away frommore » interface. In conclusion, our results demonstrate the high sensitivity of the device conductance to the position of oxygen atoms.« less
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NASA Astrophysics Data System (ADS)
Mukundan, R.
Chemical modifications of barium cerium gadolinium oxide through the substitution of Bi, Tb, Pr, Nb and Ta were attempted in an effort to increase the p-type or n-type conductivity, and to develop new mixed-conducting electrodes that are chemically compatible with the Ba(Cesb{1-x}Gdsb{x})Osb{3-x/2} electrolyte. The structure, oxygen non-stoichiometry, electronic and ionic-conductivity of several compositions in the doped-barium cerate systems were studied by X-ray diffraction, TGA, DC and AC conductivity, and EMF measurements. The cathodic overpotential of the mixed (electronic/ionic) conducting compositions in this system, on a Ba(Cesb{0.8}Gdsb{0.2})Osb{2.9} electrolyte, were also studied using Current Interruption and AC impedance techniques. The substitution of Bi into Ba(Cesb{0.9}Gdsb{0.1})Osb{2.95} lead to a significant increase in the electronic conductivity, and a total conductivity of about 0.94 S/cm was obtained for Ba(Bisb{0.5}Cesb{0.4}Gdsb{0.1})Osb3 at 800sp°C in air. However, the concentration of oxygen-ion vacancies and hence the ionic conductivity decreased due to the oxidation of Bi to the 5sp{+} state. Compositions in the Ba(Bisb{0.5}Cesb{x}Gdsb{0.5-x})Osb3 system also exhibited significant oxygen non-stoichiometry depending upon the ordering of the B-site cations and the relative concentrations of Ce and Gd. However, the absence of any detectable EMF in the non-stoichiometric compositions implied that the oxygen vacancies are strongly associated with the Bisp{3+} cations. Although highly conductive, chemically stable compositions were prepared in the Ba(Bisb{x}Cesb{y}Gdsb{1-(x+y)})Osb{3-d} system, their ionic conductivities were low. The mixed-conduction properties of Ba(Cesb{1-x}Gdsb{x})Osb{3-d} were enhanced under cathode conditions (600-800sp°C in air) by the substitution of Ce by Tb and Pr. While the substitution of Tb resulted in a decrease in the total conductivity, Pr induced a significant increase in the total conductivity at high Pr levels (≥40 mole%) due to an enhancement of the electronic conductivity. The Ba(Prsb{0.8}Gdsb{0.2})Osb{2.9} sample was found to have the best mixed-conducting properties of all the perovskites evaluated, sigmasb{T}=0.75 S/cm in air at 800sp°C, tsb{H+}=0.15 in a wet argon//dry argon gradient, and tsb{0.2-}≈ 0.05 in a dry air//dry argon gradient. The cathodic overpotentials of the mixed-conducting Pr-doped barium cerates were low, and decreased with increasing ionic and electronic conductivity of the electrode. The lowest overpotential was obtained for the Ba(Prsb{0.8}Gdsb{0.2})Osb{2.9}, cathode, and at low current densities was comparable to that of an optimized porous Pt-electrode. While the substitution of Nb and Ta for Ce lead to an enhancement in the electronic conductivity under reducing conditions associated with the increased reduction of Cesp{4+} to Cesp{3+}, the ionic-conductivity of these perovskites was low. There was no evidence for any protonic conductivity in the 15 mole% Nb and Ta substituted barium cerates. Moreover the anodic overpotential and the anode resistance of these perovskites on a Ba(Cesb{0.8}Gdsb{0.2})Osb{2.9} electrolyte were both high.
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Thermal conductivity anisotropy of metasedimentary and igneous rocks
NASA Astrophysics Data System (ADS)
Davis, Michael G.; Chapman, David S.; van Wagoner, Thomas M.; Armstrong, Phillip A.
2007-05-01
Thermal conductivity anisotropy was determined for three sets of metasedimentary and igneous rocks from central Utah, USA. Most conductivity measurements were made in transient mode with a half-space, line source instrument oriented in two orthogonal directions on a flat face cut perpendicular to bedding. One orientation of the probe yields thermal conductivity parallel to bedding (kpar) directly, the other orientation of the probe measures a product of conductivities parallel and perpendicular to bedding from which the perpendicular conductivity (kperp) is calculated. Some direct measurements of kpar and kperp were made on oriented cylindrical discs using a conventional divided bar device in steady state mode. Anisotropy is defined as kpar/kperp. Precambrian argillites from Big Cottonwood Canyon have anisotropy values from 0.8 to 2.1 with corresponding conductivity perpendicular to bedding of 2.0 to 6.2 W m-1 K-1. Anisotropy values for Price Canyon sedimentary samples are less than 1.2 with a mean of 1.04 although thermal conductivity perpendicular to bedding for the samples varied from 1.3 to 5.0 W m-1 K-1. The granitic rocks were found to be essentially isotropic with thermal conductivity perpendicular to bedding having a range of 2.2 to 3.2 W m-1 K-1 and a mean of 2.68 W m-1 K-1. The results confirm the observation by Deming [1994] that anisotropy is negligible for rocks having kperp greater than 4.0 W m-1 K-1 and generally increases for low conductivity metamorphic and clay-rich rocks. There is little evidence, however, for his suggestion that thermal conductivity anisotropy of all rocks increases systematically to about 2.5 for low thermal conductivity rocks.
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Relevance of Conduction Disorders in Bachmann's Bundle During Sinus Rhythm in Humans.
Teuwen, Christophe P; Yaksh, Ameeta; Lanters, Eva A H; Kik, Charles; van der Does, Lisette J M E; Knops, Paul; Taverne, Yannick J H J; van de Woestijne, Pieter C; Oei, Frans B S; Bekkers, Jos A; Bogers, Ad J J C; Allessie, Maurits A; de Groot, Natasja M S
2016-05-01
Bachmann's bundle (BB) is considered to be the main route of interatrial conduction and to play a role in development of atrial fibrillation (AF). The goals of this study are to characterize the presence of conduction disorders in BB during sinus rhythm and to study their relation with AF. High-resolution epicardial mapping (192 unipolar electrodes, interelectrode distance: 2 mm) of sinus rhythm was performed in 185 patients during coronary artery bypass surgery of whom 13 had a history of paroxysmal AF. Continuous rhythm monitoring was used to detect postoperative AF during the first 5 postoperative days. In 67% of the patients, BB was activated from right to left; in the remaining patients from right and middle (21%), right, central, and left (8%), or central (4%) site. Mean effective conduction velocity was 89 cm/s. Conduction block was present in most patients (75%; median 1.1%, range 0-12.8) and was higher in patients with paroxysmal AF compared with patients without a history of AF (3.2% versus 0.9%; P=0.03). A high amount of conduction block (>4%) was associated with de novo postoperative AF (P=0.02). Longitudinal lines of conduction block >10 mm were also associated with postoperative AF (P=0.04). BB may be activated through multiple directions, but the predominant route of conduction is from right to left. Conduction velocity across BB is around 90 cm/s. Conduction is blocked in both longitudinal and transverse direction in the majority of patients. Conduction disorders, particularly long lines of longitudinal conduction block, are more pronounced in patients with AF episodes. © 2016 American Heart Association, Inc.
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Current Use of Underage Alcohol Compliance Checks by Enforcement Agencies in the U.S.
Erickson, Darin J.; Lenk, Kathleen M.; Sanem, Julia R.; Nelson, Toben F.; Jones-Webb, Rhonda; Toomey, Traci L.
2014-01-01
Background Compliance checks conducted by law enforcement agents can significantly reduce the likelihood of illegal alcohol sales to underage individuals, but these checks need to be conducted using optimal methods to maintain effectiveness. Materials and Methods We conducted a national survey of local and state enforcement agencies in 2010–2011 to assess: (1) how many agencies are currently conducting underage alcohol compliance checks, (2) how many agencies that conduct compliance checks use optimal methods—including checking all establishments in the jurisdiction, conducting checks at least 3–4 times per year, conducting follow-up checks within 3 months, and penalizing the licensee (not only the server/clerk) for failing a compliance check, and (3) characteristics of the agencies that conduct compliance checks. Results Just over one third of local law enforcement agencies and over two thirds of state agencies reported conducting compliance checks. However, only a small percentage of the agencies (4–6%) reported using all of the optimal methods to maximize effectiveness of these compliance checks. Local law enforcement agencies with an alcohol-related division, those with at least one full-time officer assigned to work on alcohol, and those in larger communities were significantly more likely to conduct compliance checks. State agencies with more full-time agents and those located in states where the state agency or both state and local enforcement agencies have primary responsibility (vs. only the local law agency) for enforcing alcohol retail laws were also more likely to conduct compliance checks; however, these agency characteristics did not remain statistically significant in the multivariate analyses. Conclusions Continued effort is needed to increase the number of local and state agencies conducting compliance checks using optimal methods to reduce youth access to alcohol. PMID:24716443
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An analysis of electrical conductivity model in saturated porous media
NASA Astrophysics Data System (ADS)
Cai, J.; Wei, W.; Qin, X.; Hu, X.
2017-12-01
Electrical conductivity of saturated porous media has numerous applications in many fields. In recent years, the number of theoretical methods to model electrical conductivity of complex porous media has dramatically increased. Nevertheless, the process of modeling the spatial conductivity distributed function continues to present challenges when these models used in reservoirs, particularly in porous media with strongly heterogeneous pore-space distributions. Many experiments show a more complex distribution of electrical conductivity data than the predictions derived from the experiential model. Studies have observed anomalously-high electrical conductivity of some low-porosity (tight) formations compared to more- porous reservoir rocks, which indicates current flow in porous media is complex and difficult to predict. Moreover, the change of electrical conductivity depends not only on the pore volume fraction but also on several geometric properties of the more extensive pore network, including pore interconnection and tortuosity. In our understanding of electrical conductivity models in porous media, we study the applicability of several well-known methods/theories to electrical characteristics of porous rocks as a function of pore volume, tortuosity and interconnection, to estimate electrical conductivity based on the micro-geometrical properties of rocks. We analyze the state of the art of scientific knowledge and practice for modeling porous structural systems, with the purpose of identifying current limitations and defining a blueprint for future modeling advances. We compare conceptual descriptions of electrical current flow processes in pore space considering several distinct modeling approaches. Approaches to obtaining more reasonable electrical conductivity models are discussed. Experiments suggest more complex relationships between electrical conductivity and porosity than experiential models, particularly in low-porosity formations. However, the available theoretical models combined with simulations do provide insight to how microscale physics affects macroscale electrical conductivity in porous media.
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Patel, Shrayesh N; Javier, Anna E; Balsara, Nitash P
2013-07-23
Block copolymers that can simultaneously conduct electronic and ionic charges on the nanometer length scale can serve as innovative conductive binder material for solid-state battery electrodes. The purpose of this work is to study the electronic charge transport of poly(3-hexylthiophene)-b-poly(ethylene oxide) (P3HT-PEO) copolymers electrochemically oxidized with lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) salt in the context of a lithium battery charge/discharge cycle. We use a solid-state three-terminal electrochemical cell that enables simultaneous conductivity measurements and control over electrochemical doping of P3HT. At low oxidation levels (ratio of moles of electrons removed to moles of 3-hexylthiophene moieties in the electrode), the electronic conductivity (σe,ox) increases from 10(-7) S/cm to 10(-4) S/cm. At high oxidation levels, σe,ox approaches 10(-2) S/cm. When P3HT-PEO is used as a conductive binder in a positive electrode with LiFePO4 active material, P3HT is electrochemically active within the voltage window of a charge/discharge cycle. The electronic conductivity of the P3HT-PEO binder is in the 10(-4) to 10(-2) S/cm range over most of the potential window of the charge/discharge cycle. This allows for efficient electronic conduction, and observed charge/discharge capacities approach the theoretical limit of LiFePO4. However, at the end of the discharge cycle, the electronic conductivity decreases sharply to 10(-7) S/cm, which means the "conductive" binder is now electronically insulating. The ability of our conductive binder to switch between electronically conducting and insulating states in the positive electrode provides an unprecedented route for automatic overdischarge protection in rechargeable batteries.
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Hort, Ryan D; Revil, André; Munakata-Marr, Junko
2014-09-01
Time lapse resistivity surveys could potentially improve monitoring of permanganate-based in situ chemical oxidation (ISCO) of organic contaminants such as trichloroethene (TCE) by tracking changes in subsurface conductivity that result from injection of permanganate and oxidation of the contaminant. Bulk conductivity and pore fluid conductivity changes during unbuffered TCE oxidation using permanganate are examined through laboratory measurements and conductivity modeling using PHREEQC in fluid samples and porous media samples containing silica sand. In fluid samples, oxidation of one TCE molecule produces three chloride ions and one proton, resulting in an increase in fluid electrical conductivity despite the loss of two permanganate ions in the reaction. However, in saturated sand samples in which up to 8mM TCE was oxidized, at least 94% of the fluid conductivity associated with the presence of protons was removed within 3h of sand contact, most likely through protonation of silanol groups found on the surface of the sand grains. Minor conductivity effects most likely associated with pH-dependent reductive dissolution of manganese dioxide were also observed but not accounted for in pore-fluid conductivity modeling. Unaccounted conductivity effects resulted in an under-calculation of post-reaction pore fluid conductivity of 2.1% to 5.5%. Although small increases in the porous media formation factor resulting from precipitation of manganese dioxide were detected (about 3%), these increases could not be confirmed to be statistically significant. Both injection of permanganate and oxidation of TCE cause increases in bulk conductivity that would be detectable through time-lapse resistivity surveys in field conditions. Copyright © 2014 Elsevier B.V. All rights reserved.
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Current use of underage alcohol compliance checks by enforcement agencies in the United States.
Erickson, Darin J; Lenk, Kathleen M; Sanem, Julia R; Nelson, Toben F; Jones-Webb, Rhonda; Toomey, Traci L
2014-06-01
Compliance checks conducted by law enforcement agents can significantly reduce the likelihood of illegal alcohol sales to underage individuals, but these checks need to be conducted using optimal methods to maintain effectiveness. We conducted a national survey of local and state enforcement agencies from 2010 to 2011 to assess: (i) how many agencies are currently conducting underage alcohol compliance checks, (ii) how many agencies that conduct compliance checks use optimal methods-including checking all establishments in the jurisdiction, conducting checks at least 3 to 4 times per year, conducting follow-up checks within 3 months, and penalizing the licensee (not only the server/clerk) for failing a compliance check, and (iii) characteristics of the agencies that conduct compliance checks. Just over one-third of local law enforcement agencies and over two-thirds of state agencies reported conducting compliance checks. However, only a small percentage of the agencies (4 to 6%) reported using all of the optimal methods to maximize effectiveness of these compliance checks. Local law enforcement agencies with an alcohol-related division, those with at least 1 full-time officer assigned to work on alcohol, and those in larger communities were significantly more likely to conduct compliance checks. State agencies with more full-time agents and those located in states where the state agency or both state and local enforcement agencies have primary responsibility (vs. only the local law agency) for enforcing alcohol retail laws were also more likely to conduct compliance checks; however, these agency characteristics did not remain statistically significant in the multivariate analyses. Continued effort is needed to increase the number of local and state agencies conducting compliance checks using optimal methods to reduce youth access to alcohol. Copyright © 2014 by the Research Society on Alcoholism.
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Maximum on the Electrical Conductivity Polytherm of Molten TeCl4
NASA Astrophysics Data System (ADS)
Salyulev, Alexander B.; Potapov, Alexei M.
2017-05-01
The electrical conductivity of molten TeCl4 was measured up to 761K, i.e. 106 degrees above the normal boiling point of the salt. For the first time it was found that TeCl4 electrical conductivity polytherm has a maximum. It was recorded at 705K (κmax=0.245 Sm/cm), whereupon the conductivity decreases as the temperature rises. The activation energy of electrical conductivity was calculated.
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Modelling the Effect of Fruit Growth on Surface Conductance to Water Vapour Diffusion
GIBERT, CAROLINE; LESCOURRET, FRANÇOISE; GÉNARD, MICHEL; VERCAMBRE, GILLES; PÉREZ PASTOR, ALEJANDRO
2005-01-01
• Background and Aims A model of fruit surface conductance to water vapour diffusion driven by fruit growth is proposed. It computes the total fruit conductance by integrating each of its components: stomata, cuticle and cracks. • Methods The stomatal conductance is computed from the stomatal density per fruit and the specific stomatal conductance. The cuticular component is equal to the proportion of cuticle per fruit multiplied by its specific conductance. Cracks are assumed to be generated when pulp expansion rate exceeds cuticle expansion rate. A constant percentage of cracks is assumed to heal each day. The proportion of cracks to total fruit surface area multiplied by the specific crack conductance accounts for the crack component. The model was applied to peach fruit (Prunus persica) and its parameters were estimated from field experiments with various crop load and irrigation regimes. • Key Results The predictions were in good agreement with the experimental measurements and for the different conditions (irrigation and crop load). Total fruit surface conductance decreased during early growth as stomatal density, and hence the contribution of the stomatal conductance, decreased from 80 to 20 % with fruit expansion. Cracks were generated for fruits exhibiting high growth rates during late growth and the crack component could account for up to 60 % of the total conductance during the rapid fruit growth. The cuticular contribution was slightly variable (around 20 %). Sensitivity analysis revealed that simulated conductance was highly affected by stomatal parameters during the early period of growth and by both crack and stomatal parameters during the late period. Large fruit growth rate leads to earlier and greater increase of conductance due to higher crack occurrence. Conversely, low fruit growth rate accounts for a delayed and lower increase of conductance. • Conclusions By predicting crack occurrence during fruit growth, this model could be helpful in managing cropping practices for integrated plant protection. PMID:15655107
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NASA Astrophysics Data System (ADS)
Swint, Amy Lynn
Changes in the in-plane conductance of conductive thin films are observed as a result of chemical adsorption at the surface. Reaction of the indium tin oxide (ITO) surface with Bronsted acids (bases) leads to increases (decreases) in its in-plane conductance as measured by a four-point probe configuration. The conductance varies monotonically with pH suggesting that the degree of surface protonation or hydroxylation controls the surface charge density, which in turn affects the width of the n-type depletion layer, and ultimately the in-plane conductance. Measurements at constant pH with a series of tetraalkylammonium hydroxide species of varying cation size indicate that surface dipoles also affect ITO conductance by modulating the magnitude of the surface polarization. Modulating the double layer with varying aqueous salt solutions also affects ITO conductance, though not to the same degree as strong Bronsted acids and bases. Solvents of varying dielectric constant and proton donating ability (ethanol, dimethylformamide) decrease ITO conductance relative to H2O. In addition, changing solvent gives rise to thermally-derived conductance transients, which result from exothermic solvent mixing. The self-assembly of alkanethiols at the surface increases the conductance of ITO films, most likely through carrier population effects. In all cases examined the combined effects of surface charge, adsorbed dipole layer magnitude and carrier injection are responsible for altering the ITO conductance. Besides being directly applicable to the control of electronic properties, these results also point to the use of four-point probe resistance measurements in condensed phase sensing applications. Ultrasensitive conductance-based gas phase sensing of organothiol adsorption to gold nanowires is accomplished with a limit of detection in the 105 molecule range. Further refinement of the inherently low noise resistance measurement may lead to observation of single adsorption events at the gold surface.
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Meunier, Félicien; Zarebanadkouki, Mohsen; Ahmed, Mutez A; Carminati, Andrea; Couvreur, Valentin; Javaux, Mathieu
2018-01-26
Improving or maintaining crop productivity under conditions of long term change of soil water availability and atmosphere demand for water is one the big challenges of this century. It requires a deep understanding of crop water acquisition properties, i.e. root system architecture and root hydraulic properties among other characteristics of the soil-plant-atmosphere continuum. A root pressure probe technique was used to measure the root hydraulic conductances of seven-week old maize and lupine plants grown in sandy soil. Unbranched root segments were excised in lateral, seminal, crown and brace roots of maize, and in lateral roots of lupine. Their total hydraulic conductance was quantified under steady-state hydrostatic gradient for progressively shorter segments. Furthermore, the axial conductance of proximal root regions removed at each step of root shortening was measured as well. Analytical solutions of the water flow equations in unbranched roots developed recently and relating root total conductance profiles to axial and radial conductivities were used to retrieve the root radial hydraulic conductivity profile along each root type, and quantify its uncertainty. Interestingly, the optimized root radial conductivities and measured axial conductances displayed significant differences across root types and species. However, the measured root total conductances did not differ significantly. As compared to measurements reported in the literature, our axial and radial conductivities concentrate in the lower range of herbaceous species hydraulic properties. In a final experiment, the hydraulic conductances of root junctions to maize stem were observed to highly depend on root type. Surprisingly maize brace root junctions were an order of magnitude more conductive than the other crown and seminal roots, suggesting potential regulation mechanism for root water uptake location and a potential role of the maize brace roots for water uptake more important than reported in the literature. Copyright © 2018 Elsevier GmbH. All rights reserved.
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Adachi, Shunsuke; Tsuru, Yukiko; Kondo, Motohiko; Yamamoto, Toshio; Arai-Sanoh, Yumiko; Ando, Tsuyu; Ookawa, Taiichiro; Yano, Masahiro; Hirasawa, Tadashi
2010-01-01
Background and Aims The rate of photosynthesis in paddy rice often decreases at noon on sunny days because of water stress, even under submerged conditions. Maintenance of higher rates of photosynthesis during the day might improve both yield and dry matter production in paddy rice. A high-yielding indica variety, ‘Habataki’, maintains a high rate of leaf photosynthesis during the daytime because of the higher hydraulic conductance from roots to leaves than in the standard japonica variety ‘Sasanishiki’. This research was conducted to characterize the trait responsible for the higher hydraulic conductance in ‘Habataki’ and identified a chromosome region for the high hydraulic conductance. Methods Hydraulic conductance to passive water transport and to osmotic water transport was determined for plants under intense transpiration and for plants without transpiration, respectively. The varietal difference in hydraulic conductance was examined with respect to root surface area and hydraulic conductivity (hydraulic conductance per root surface area, Lp). To identify the chromosome region responsible for higher hydraulic conductance, chromosome segment substitution lines (CSSLs) derived from a cross between ‘Sasanishiki’ and ‘Habataki’ were used. Key Results The significantly higher hydraulic conductance resulted from the larger root surface area not from Lp in ‘Habataki’. A chromosome region associated with the elevated hydraulic conductance was detected between RM3916 and RM2431 on the long arm of chromosome 4. The CSSL, in which this region was substituted with the ‘Habataki’ chromosome segment in the ‘Sasanishiki’ background, had a larger root mass than ‘Sasanishiki’. Conclusions The trait for increasing plant hydraulic conductance and, therefore, maintaining the higher rate of leaf photosynthesis under the conditions of intense transpiration in ‘Habataki’ was identified, and it was estimated that there is at least one chromosome region for the trait located on chromosome 4. PMID:20810742
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Revisiting the block method for evaluating thermal conductivities of clay and granite
USDA-ARS?s Scientific Manuscript database
Determination of thermal conductivities of porous media using the contact method is revisited and revalidated with consideration of thermal contact resistance. Problems that limit the accuracy of determination of thermal conductivities of porous media are discussed. Thermal conductivities of granite...
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16 CFR 5.55 - Conduct of investigation.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Conduct of investigation. 5.55 Section 5.55 Commercial Practices FEDERAL TRADE COMMISSION ORGANIZATION, PROCEDURES AND RULES OF PRACTICE STANDARDS OF CONDUCT Disciplinary Actions Concerning Postemployment Conflict of Interest § 5.55 Conduct of...
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Organic conductive films for semiconductor electrodes
Frank, Arthur J.
1984-01-01
According to the present invention, improved electrodes overcoated with conductive polymer films and preselected catalysts are provided. The electrodes typically comprise an inorganic semiconductor overcoated with a charge conductive polymer film comprising a charge conductive polymer in or on which is a catalyst or charge-relaying agent.
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Rapid prototype extruded conductive pathways
Bobbitt, III, John T.
2016-06-21
A process of producing electrically conductive pathways within additively manufactured parts and similar parts made by plastic extrusion nozzles. The process allows for a three-dimensional part having both conductive and non-conductive portions and allows for such parts to be manufactured in a single production step.
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Electrically-conductive proppant and methods for making and using same
Cannan, Chad; Roper, Todd; Savoy, Steve; Mitchell, Daniel R.
2016-09-06
Electrically-conductive sintered, substantially round and spherical particles and methods for producing such electrically-conductive sintered, substantially round and spherical particles from an alumina-containing raw material. Methods for using such electrically-conductive sintered, substantially round and spherical particles in hydraulic fracturing operations.
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21 CFR 868.5120 - Anesthesia conduction catheter.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Anesthesia conduction catheter. 868.5120 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5120 Anesthesia conduction catheter. (a) Identification. An anesthesia conduction catheter is a flexible tubular device used to inject...
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21 CFR 868.5120 - Anesthesia conduction catheter.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Anesthesia conduction catheter. 868.5120 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5120 Anesthesia conduction catheter. (a) Identification. An anesthesia conduction catheter is a flexible tubular device used to inject...
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5 CFR 1632.3 - Conduct of agency business.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Conduct of agency business. 1632.3... OBSERVATION OF MEETINGS § 1632.3 Conduct of agency business. Members shall not jointly conduct or dispose of official Board business other than in accordance with this part. ...
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32 CFR 147.7 - Guideline E-Personal conduct.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 32 National Defense 1 2010-07-01 2010-07-01 false Guideline E-Personal conduct. 147.7 Section 147... CIVILIAN ADJUDICATIVE GUIDELINES FOR DETERMINING ELIGIBILITY FOR ACCESS TO CLASSIFIED INFORMATION Adjudication § 147.7 Guideline E—Personal conduct. (a) The concern. Conduct involving questionable judgment...
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38 CFR 21.6362 - Satisfactory conduct and cooperation.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Satisfactory conduct and cooperation. 21.6362 Section 21.6362 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS... Pension Recipients Satisfactory Conduct and Cooperation § 21.6362 Satisfactory conduct and cooperation...
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An Alternative to Impedance Screening: Unoccluded Frontal Bone Conduction Screening.
ERIC Educational Resources Information Center
Square, Regina; And Others
1985-01-01
A bone conduction hearing screening test using frontal bone oscillator placement was compared with pure-tone air-conduction screening and impedance audiometry with 114 preschoolers. Unoccluded frontal bone conduction testing produced screening results not significantly different from results obtained by impedance audiometry. (CL)!
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7 CFR 1485.28 - Ethical conduct.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 10 2013-01-01 2013-01-01 false Ethical conduct. 1485.28 Section 1485.28 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY CREDIT CORPORATION, DEPARTMENT OF... COMMODITIES Market Access Program § 1485.28 Ethical conduct. (a) A MAP Participant shall conduct its business...
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7 CFR 1485.28 - Ethical conduct.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 10 2014-01-01 2014-01-01 false Ethical conduct. 1485.28 Section 1485.28 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY CREDIT CORPORATION, DEPARTMENT OF... COMMODITIES Market Access Program § 1485.28 Ethical conduct. (a) A MAP Participant shall conduct its business...
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21 CFR 868.5120 - Anesthesia conduction catheter.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Anesthesia conduction catheter. 868.5120 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5120 Anesthesia conduction catheter. (a) Identification. An anesthesia conduction catheter is a flexible tubular device used to inject...
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Method for electrically producing dispersions of a nonconductive fluid in a conductive medium
DePaoli, D.W.; Tsouris, C.; Feng, J.Q.
1998-06-09
A method is described for use in electrically forming dispersions of a nonconducting fluid in a conductive medium that minimizes power consumption, gas generation, and sparking between the electrode of the nozzle and the conductive medium. The method utilizes a nozzle having a passageway, the wall of which serves as the nozzle electrode, for the transport of the nonconducting fluid into the conductive medium. A second passageway provides for the transport of a flowing low conductivity buffer fluid which results in a region of the low conductivity buffer fluid immediately adjacent the outlet from the first passageway to create the necessary protection from high current drain and sparking. An electrical potential difference applied between the nozzle electrode and an electrode in contact with the conductive medium causes formation of small droplets or bubbles of the nonconducting fluid within the conductive medium. A preferred embodiment has the first and second passageways arranged in a concentric configuration, with the outlet tip of the first passageway withdrawn into the second passageway. 4 figs.
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Method for electrically producing dispersions of a nonconductive fluid in a conductive medium
DePaoli, David W.; Tsouris, Constantinos; Feng, James Q.
1998-01-01
A method for use in electrically forming dispersions of a nonconducting fluid in a conductive medium that minimizes power consumption, gas generation, and sparking between the electrode of the nozzle and the conductive medium. The method utilizes a nozzle having a passageway, the wall of which serves as the nozzle electrode, for the transport of the nonconducting fluid into the conductive medium. A second passageway provides for the transport of a flowing low conductivity buffer fluid which results in a region of the low conductivity buffer fluid immediately adjacent the outlet from the first passageway to create the necessary protection from high current drain and sparking. An electrical potential difference applied between the nozzle electrode and an electrode in contact with the conductive medium causes formation of small droplets or bubbles of the nonconducting fluid within the conductive medium. A preferred embodiment has the first and second passageways arranged in a concentric configuration, with the outlet tip of the first passageway withdrawn into the second passageway.
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NASA Astrophysics Data System (ADS)
Ahmadi Nadooshan, Afshin
2017-03-01
In this study, the effects of temperature (20 °C
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Microstructural modeling of thermal conductivity of high burn-up mixed oxide fuel
NASA Astrophysics Data System (ADS)
Teague, Melissa; Tonks, Michael; Novascone, Stephen; Hayes, Steven
2014-01-01
Predicting the thermal conductivity of oxide fuels as a function of burn-up and temperature is fundamental to the efficient and safe operation of nuclear reactors. However, modeling the thermal conductivity of fuel is greatly complicated by the radially inhomogeneous nature of irradiated fuel in both composition and microstructure. In this work, radially and temperature-dependent models for effective thermal conductivity were developed utilizing optical micrographs of high burn-up mixed oxide fuel. The micrographs were employed to create finite element meshes with the OOF2 software. The meshes were then used to calculate the effective thermal conductivity of the microstructures using the BISON [1] fuel performance code. The new thermal conductivity models were used to calculate thermal profiles at end of life for the fuel pellets. These results were compared to thermal conductivity models from the literature, and comparison between the new finite element-based thermal conductivity model and the Duriez-Lucuta model was favorable.
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Recent Development of Nanomaterial-Doped Conductive Polymers
NASA Astrophysics Data System (ADS)
Asyraf, Mohammad; Anwar, Mahmood; Sheng, Law Ming; Danquah, Michael K.
2017-12-01
Conductive polymers (CPs) have received significant research attention in material engineering for applications in microelectronics, micro-scale sensors, electromagnetic shielding, and micro actuators. Numerous research efforts have been focused on enhancing the conductivity of CPs by doping. Various conductive materials, such as metal nanoparticles and carbon-based nanoparticles, and structures, such as silver nanoparticles and graphene nanosheets, have been converted into polypyrrole and polypyrrole compounds as the precursors to developing hybrids, conjugates, or crystal nodes within the matrix to enhance the various structural properties, particularly the electrical conductivity. This article reviews nanomaterial doping of conductive polymers alongside technological advancements in the development and application of nanomaterial-doped polymeric systems. Emphasis is given to conductive nanomaterials such as nano-silver particles and carbon-based nanoparticles, graphene nano-sheets, fullerene, and carbon nanotubes (CNT) as dopants for polypyrrole-based CPs. The nature of induced electrical properties including electromagnetic absorption, electrical capacitance, and conductivities of polypyrrole systems is also discussed. The prospects and challenges associated with the development and application of CPs are also presented.
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Vail, III, William Banning
2001-01-01
Methods of operation of different types of multiple electrode apparatus vertically disposed in a cased well to measure information useful to determine the resistivity of adjacent geological formations from within the cased well are described. The multiple electrode apparatus has a plurality of spaced apart voltage measurement electrodes that electrically engage a portion of the interior of the cased well. During measurements of information useful to determine formation resistivity, current is conducted between a first current conducting electrode in electrical contact with the interior of the cased well to a second current conducting electrode that is also in electrical contact with the interior of the cased well. The first and second current conducting electrodes are separated by a distance sufficient so that at least a portion of the current conducted between the first and second current conducting electrodes is conducted through the geological formation of interest.
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Thermal conductivity of graphene nanoribbons accounting for phonon dispersion and polarization
NASA Astrophysics Data System (ADS)
Wang, Yingjun; Xie, Guofeng
2015-12-01
The relative contribution to heat conduction by different phonon branches is still an intriguing and open question in phonon transport of graphene nanoribbons (GNRs). By incorporating the direction-dependent phonon-boundary scattering into the linearized phonon Boltzmann transport equation, we find that because of lower Grüneisen parameter, the TA phonons have the major contribution to thermal conductivity of GNRs, and in the case of smooth edge and micron-length of GNRS, the relative contribution of TA branch to thermal conductivity is over 50%. The length and edge roughness of GNRs have distinct influences on the relative contribution of different polarization branches to thermal conductivity. The contribution of TA branch to thermal conductivity increases with increasing the length or decreasing the edge roughness of GNRs. On the contrary, the contribution of ZA branch to thermal conductivity increases with decreasing the length or increasing the edge roughness of GNRs. The contribution of LA branch is length and roughness insensitive. Our findings are helpful for understanding and engineering the thermal conductivity of GNRs.
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Process for analyzing CO.sub.2 in seawater
Atwater, James E.; Akse, James R.; DeHart, Jeffrey
1997-01-01
The process of this invention comprises providing a membrane for separating CO.sub.2 into a first CO.sub.2 sample phase and a second CO.sub.2 analyte phase. CO.sub.2 is then transported through the membrane thereby separating the CO.sub.2 with the membrane into a first CO.sub.2 sample phase and a second CO.sub.2 analyte liquid phase including an ionized, conductive, dissociated CO.sub.2 species. Next, the concentration of the ionized, conductive, dissociated CO.sub.2 species in the second CO.sub.2 analyte liquid phase is chemically amplified using a water-soluble chemical reagent which reversibly reacts with undissociated CO.sub.2 to produce conductivity changes therein corresponding to fluctuations in the partial pressure of CO.sub.2 in the first CO.sub.2 sample phase. Finally, the chemically amplified, ionized, conductive, dissociated CO.sub.2 species is introduced to a conductivity measuring instrument. Conductivity changes in the chemically amplified, ionized, conductive, dissociated CO.sub.2 species are detected using the conductivity measuring instrument.
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Li, Zheng; Niu, Li-Hua; Yuan, Feng-Hui; Guan, De-Xin; Wang, An-Zhi; Jin, Chang-Jie; Wu, Jia-Bing
2012-11-01
By using Granier' s thermal dissipation probe, the sap flow of poplar in a poplar-maize agroforestry system in west Liaoning was continuously measured, and as well, the environmental factors such as air temperature, air humidity, net radiation, wind speed, soil temperature, and soil moisture content were synchronically measured. Based on the sap flow data, the canopy conductance of poplar was calculated with simplified Penman-Monteith equation. In the study area, the diurnal variation of poplar' s canopy conductance showed a "single peak" curve, whereas the seasonal variation showed a decreasing trend. There was a negative logarithm relationship between the canopy conductance and vapor pressure deficit, with the sensitivity of canopy conductance to vapor pressure deficit change decreased gradually from May to September. The canopy conductance had a positive relationship with solar radiation. In different months, the correlation degree of canopy conductance with environmental factors differed. The vapor pressure deficit in the whole growth period of poplar was the most significant environmental factor correlated with the canopy conductance.
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NASA Astrophysics Data System (ADS)
El-Sayed, S. A.; Morsy, M. A.
2018-05-01
Amorphous chalcogenide composition AS4Se3Te3 is prepared by conventional quenching technique. The separate annealing or γ quanta irradiation not effect on the dc conductivity properties of the prepared composition. When the prepared samples are subjected to simultaneous annealing at temperature 413 K and γ quanta irradiation the dc conductivity increases. The dark dc conductivity increases by increasing the time of exposure to γ irradiation. At irradiation dose 1.47 × 104 Gy the dc conductivity starts to have metallic like conductivity character. These samples could be used as high temperature γ quanta dosimeter. By applying scaling theory on the samples irradiated with different dose of γ irradiation the critical exponents are determined and found to be < 2. The dark dc conductivity continuously decreases to 0 as temperature tends to zero. The steric value is low in the insulator side of conductivity, but high and almost saturated in the metallic side of conductivity.
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AC conductivity and Dielectric Study of Chalcogenide Glasses of Se-Te-Ge System
NASA Astrophysics Data System (ADS)
Salman, Fathy
2004-01-01
The ac conductivity and dielectric properties of glassy system SexTe79 - xGe21, with x = 11, 14, 17 at.%, has been studied at temperatures 300 to 450 K and over a wide range of frequencies (50 Hz to 500 kHz). Experimental results indicate that the ac conductivity and the dielectric constants depend on temperature, frequency and Se content. The conductivity as a function of frequency exhibited two components: dc conductivity s dc, and ac conductivity s ac, where s ac ˜ w s. The mechanism of ac conductivity can be reasonably interpreted in terms of the correlated barrier hopping model (CBH). The activation energies are estimated and discussed. The dependence of ac conductivity and dielectric constants on the Se content x can be interpreted as the effect of Se fraction on the positional disorder. The impedance plot at each temperature appeared as a semicircle passes through the origin. Each semicircle is represented by an equivalent circuit of parallel resistance Rb and capacitance Cb.
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Random network model of electrical conduction in two-phase rock
NASA Astrophysics Data System (ADS)
Fuji-ta, Kiyoshi; Seki, Masayuki; Ichiki, Masahiro
2018-05-01
We developed a cell-type lattice model to clarify the interconnected conductivity mechanism of two-phase rock. We quantified electrical conduction networks in rock and evaluated electrical conductivity models of the two-phase interaction. Considering the existence ratio of conductive and resistive cells in the model, we generated natural matrix cells simulating a natural mineral distribution pattern, using Mersenne Twister random numbers. The most important and prominent feature of the model simulation is a drastic increase in the pseudo-conductivity index for conductor ratio R > 0.22. This index in the model increased from 10-4 to 100 between R = 0.22 and 0.9, a change of four orders of magnitude. We compared our model responses with results from previous model studies. Although the pseudo-conductivity computed by the model differs slightly from that of the previous model, model responses can account for the conductivity change. Our modeling is thus effective for quantitatively estimating the degree of interconnection of rock and minerals.
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Microstructural Modeling of Thermal Conductivity of High Burn-up Mixed Oxide Fuel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Melissa Teague; Michael Tonks; Stephen Novascone
2014-01-01
Predicting the thermal conductivity of oxide fuels as a function of burn-up and temperature is fundamental to the efficient and safe operation of nuclear reactors. However, modeling the thermal conductivity of fuel is greatly complicated by the radially inhomogeneous nature of irradiated fuel in both composition and microstructure. In this work, radially and temperature-dependent models for effective thermal conductivity were developed utilizing optical micrographs of high burn-up mixed oxide fuel. The micrographs were employed to create finite element meshes with the OOF2 software. The meshes were then used to calculate the effective thermal conductivity of the microstructures using the BISONmore » fuel performance code. The new thermal conductivity models were used to calculate thermal profiles at end of life for the fuel pellets. These results were compared to thermal conductivity models from the literature, and comparison between the new finite element-based thermal conductivity model and the Duriez–Lucuta model was favorable.« less
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NASA Technical Reports Server (NTRS)
Smith, Joseph G., Jr.; Watson, Kent A.; Delozier, Donavon M.; Connell, John W.
2003-01-01
Thin film membranes of space environmentally stable polymeric materials possessing low color/solar absorptivity (alpha) are of interest for potential applications on Gossamer spacecraft. In addition to these properties, sufficient electrical conductivity is required in order to dissipate electrostatic charge (ESC) build-up brought about by the charged orbital environment. One approach to achieve sufficient electrical conductivity for ESC mitigation is the incorporation of single wall carbon nanotubes (SWNTs). However, when the SWNTs are dispersed throughout the polymer matrix, the nanocomposite films tend to be significantly darker than the pristine material resulting in a higher alpha. The incorporation of conductive additives in combination with a decreased loading level of SWNTs is one approach for improving alpha while retaining conductivity. Taken individually, the low loading level of conductive additives and SWNTs is insufficient in achieving the percolation level necessary for electrical conductivity. When added simultaneously to the film, conductivity is achieved through a synergistic effect. The chemistry, physical, and mechanical properties of the nanocomposite films will be presented.
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Apparatus for detecting alpha radiation in difficult access areas
Steadman, P.; MacArthur, D.W.
1997-09-02
An electrostatic alpha radiation detector for measuring alpha radiation emitted from inside an enclosure comprising an electrically conductive expandable electrode for insertion into the enclosure is disclosed. After insertion, the electrically conductive expandable electrode is insulated from the enclosure and defines a decay cavity between the electrically conductive expandable electrode and the enclosure so that air ions generated in the decay cavity are electrostatically captured by the electrically conductive expandable electrode and the enclosure when an electric potential is applied between the electrically conductive expandable electrode and the enclosure. Indicator means are attached to the electrically conductive expandable electrode for indicating an electrical current produced by generation of the air ions generated in the decay cavity by collisions between air molecules and the alpha particles emitted from the enclosure. A voltage source is connected between the indicator means and the electrically conductive enclosure for creating an electric field between the electrically conductive expandable electrode and the enclosure. 4 figs.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Pike, J.; Reboul, S.
2015-06-01
SRS High Level Waste Tank Farm personnel rely on conductivity probes for detection of incipient overflow conditions in waste tanks. Minimal information is available concerning the sensitivity that must be achieved such that that liquid detection is assured. Overly sensitive electronics results in numerous nuisance alarms for these safety-related instruments. In order to determine the minimum sensitivity required of the probe, Tank Farm Engineering personnel need adequate conductivity data to improve the existing designs. Little or no measurements of liquid waste conductivity exist; however, the liquid phase of the waste consists of inorganic electrolytes for which the conductivity may bemore » calculated. Savannah River Remediation (SRR) Tank Farm Facility Engineering requested SRNL to determine the conductivity of the supernate resident in SRS waste Tank 40 experimentally as well as computationally. In addition, SRNL was requested to develop a correlation, if possible, that would be generally applicable to liquid waste resident in SRS waste tanks. A waste sample from Tank 40 was analyzed for composition and electrical conductivity as shown in Table 4-6, Table 4-7, and Table 4-9. The conductivity for undiluted Tank 40 sample was 0.087 S/cm. The accuracy of OLI Analyzer™ was determined using available literature data. Overall, 95% of computed estimates of electrical conductivity are within ±15% of literature values for component concentrations from 0 to 15 M and temperatures from 0 to 125 °C. Though the computational results are generally in good agreement with the measured data, a small portion of literature data deviates as much as ±76%. A simplified model was created that can be used readily to estimate electrical conductivity of waste solution in computer spreadsheets. The variability of this simplified approach deviates up to 140% from measured values. Generally, this model can be applied to estimate the conductivity within a factor of two. The comparison of the simplified model to pure component literature data suggests that the simplified model will tend to under estimate the electrical conductivity. Comparison of the computed Tank 40 conductivity with the measured conductivity shows good agreement within the range of deviation identified based on pure component literature data.« less
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Electrical properties of polycrystalline olivine: evidence for grain boundary transport
NASA Astrophysics Data System (ADS)
Ten Grotenhuis, S. M.; Drury, M. R.; Peach, C. J.; Spiers, C. J.
2003-12-01
The physical and chemical properties of grain boundaries are known to play an important role in determining the electrical properties of polycrystalline oxides. Grain boundaries can either enhance conductivity if the transport of charge carriers along the grain boundaries is faster than through the lattice, or grain boundaries can reduce conductivity if the grain boundaries block the transport of charge carriers. The purpose of the experiments presented here is to deduce the mechanisms responsible for electrical conductivity in fine-grained forsterite, the Mg-end member of olivine, in order to get a better understanding of the contribution of grain boundary transport, of the properties of the grain boundaries, and to determine any relation between grain size and conductivity. A relationship between grain size and conductivity at high temperature could potentially be used to interpret zones of anomalous conductivity in the upper mantle. The materials studied consist of fine-grained forsterite (Mg2SiO4) with a minor amount (5%) of enstatite (MgSiO3) added. The electrical conductivity of three melt-free synthetic polycrystalline samples, with grain sizes between 1.1 and 4.7 mm, was measured at temperatures up to 1470° C. The complex impedance plots display one clear arc, indicating a single dominant conduction mechanism. Bulk conductivity is inversely proportional to the grain size of the different samples. This relation suggests that grain boundary diffusion of the charge carriers is controlling the electrical conductivity of the samples. The activation energy for diffusion of the charge carriers lies between 315 and 323 kJ/mol. This resembles previous data on grain boundary diffusion of Mg in forsterite and grain boundary diffusion creep. A geometrical model of less conducting cubic grains and more conducting grain boundaries agrees well with the experimental data. This model is applied to a natural mantle shear zone to predict the conductivity contrast between fine-grained shear zones and less deformed regions in the lithosphere. Upper mantle shear zones are predicted to have 1.5 to 2 orders of magnitude higher conductivity than less deformed regions in the lithosphere. This may mean that fine-grained shear zones can be detected using magnetotelluric methods.
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Hall, David R [Provo, UT; Fox, Joe [Spanish Fork, UT
2008-01-15
A transmission system in a downhole component comprises a data transmission element in both ends of the downhole component. Each data transmission element houses an electrically conducting coil in a MCEI circular trough. An electrical conductor connects both the transmission elements. The electrical conductor comprises at least three electrically conductive elements insulated from each other. In the preferred embodiment the electrical conductor comprises an electrically conducting outer shield, an electrically conducting inner shield and an electrical conducting core. In some embodiments of the present invention, the electrical conductor comprises an electrically insulating jacket. In other embodiments, the electrical conductor comprises a pair of twisted wires. In some embodiments, the electrical conductor comprises semi-conductive material.
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Non-permeable substrate carrier for electroplating
Abas, Emmanuel Chua; Chen, Chen-An; Ma, Diana Xiaobing; Ganti, Kalyana Bhargava
2012-11-27
One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The substrate carrier comprises a non-conductive carrier body on which the substrates are to be held. Electrically-conductive lines are embedded within the carrier body, and a plurality of contact clips are coupled to the electrically-conductive lines embedded within the carrier body. The contact clips hold the substrates in place and electrically couple the substrates to the electrically-conductive lines. The non-conductive carrier body is continuous so as to be impermeable to flow of electroplating solution through the non-conductive carrier body. Other embodiments, aspects and features are also disclosed.
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Conducting nanotubes or nanostructures based composites, method of making them and applications
NASA Technical Reports Server (NTRS)
Gupta, Mool C. (Inventor); Yang, Yonglai (Inventor); Dudley, Kenneth L. (Inventor); Lawrence, Roland W. (Inventor)
2013-01-01
An electromagnetic interference (EMI) shielding material includes a matrix of a dielectric or partially conducting polymer, such as foamed polystyrene, with carbon nanotubes or other nanostructures dispersed therein in sufficient concentration to make the material electrically conducting. The composite is formed by dispersing the nanotube material in a solvent in which the dielectric or partially conducting polymer is soluble and mixing the resulting suspension with the dielectric or partially conducting polymer. A foaming agent can be added to produce a lightweight foamed material. An organometallic compound can be added to enhance the conductivity further by decomposition into a metal phase.
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NASA Astrophysics Data System (ADS)
Gref, Orman; Weizman, Moshe; Rhein, Holger; Gabriel, Onno; Gernert, Ulrich; Schlatmann, Rutger; Boit, Christian; Friedrich, Felice
2016-06-01
A conductive atomic force microscope is used to study the local topography and conductivity of laser-fired aluminum contacts on KOH-structured multicrystalline silicon surfaces. A significant increase in conductivity is observed in the laser-affected area. The area size and spatial uniformity of this enhanced conductivity depends on the laser energy fluence. The laser-affected area shows three ring-shaped regimes of different conductance depending on the local aluminum and oxygen concentration. Finally, it was found that the topographic surface structure determined by the silicon grain orientation does not significantly affect the laser-firing process.
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Non-permeable substrate carrier for electroplating
Abas, Emmanuel Chua; Chen, Chen-an; Ma, Diana Xiaobing; Ganti, Kalyana; Divino, Edmundo Anida; Ermita, Jake Randal G.; Capulong, Jose Francisco S.; Castillo, Arnold Villamor
2015-12-29
One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The substrate carrier comprises a non-conductive carrier body on which the substrates are to be held. Electrically-conductive lines are embedded within the carrier body, and a plurality of contact clips are coupled to the electrically-conductive lines embedded within the carrier body. The contact clips hold the substrates in place and electrically couple the substrates to the electrically-conductive lines. The non-conductive carrier body is continuous so as to be impermeable to flow of electroplating solution through the non-conductive carrier body. Other embodiments, aspects and features are also disclosed.
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Measuring skin conductance over clothes.
Hong, Ki Hwan; Lee, Seung Min; Lim, Yong Gyu; Park, Kwang Suk
2012-11-01
We propose a new method that measures skin conductance over clothes to nonintrusively monitor the changes in physiological conditions affecting skin conductance during daily activities. We selected the thigh-to-thigh current path and used an indirectly coupled 5-kHz AC current for the measurement. While varying the skin conductance by the Valsalva maneuver method, the results were compared with the traditional galvanic skin response (GSR) measured directly from the fingers. Skin conductance measured using a 5-kHz current displayed a highly negative correlation with the traditional GSR and the current measured over clothes reflected the rate of change of the conductance of the skin beneath.
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Ion conduction in high ion content PEO-based ionomers
NASA Astrophysics Data System (ADS)
Caldwell, David, II; Maranas, Janna
Solid Polymer Electrolytes (SPEs) can enable the design of batteries that are safer and have higher capacity than batteries with traditional volatile organic electrolytes. The current limitation for SPEs is their low conductivity, resulting from a conduction mechanism strongly coupled to the dynamics of the polymer host matrix. Our previous work indicated the possibility of a conduction mechanism through the use of ion aggregates. In order to investigate this mechanism, we performed a series of molecular dynamics simulations of PEO-based ionomers at high ion content. Our results indicate that conduction through ion aggregates are partially decoupled from polymer dynamics and could enable the development of higher conductive SPEs.
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Electrostatically controlled heat shutter
NASA Technical Reports Server (NTRS)
Derr, L. J. (Inventor)
1973-01-01
A heat transfer assembly for conducting thermal energy is described. The assembly includes a hermetically sealed container enclosing a quantity of inert gas such as nitrogen. Two opposed walls of the container have high thermal conducting characteristics while the connecting walls have low thermal conducting characteristics. Electrodes are positioned adjacent to the high thermal conducing walls and biased relative to the conducting walls to a corona potential for creating an ionic gas wind which must contact the conducting walls to be neutralized. The contact of the gas molecules permits the maximum thermal energy transfer between the walls. Baffles can be positioned adjacent to the electrodes to regulate gas flow between the high thermal conducting surfaces.
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Temperament and Parenting during the First Year of Life Predict Future Child Conduct Problems
Lahey, Benjamin B.; Van Hulle, Carol A.; Keenan, Kate; Rathouz, Paul J.; D’Onofrio, Brian M.; Rodgers, Joseph Lee; Waldman, Irwin D.
2010-01-01
Predictive associations between parenting and temperament during the first year of life and child conduct problems were assessed longitudinally in 1,863 offspring of a representative sample of women. Maternal ratings of infant fussiness, activity level, predictability, and positive affect each independently predicted maternal ratings of conduct problems during ages 4–13 years. Furthermore, a significant interaction indicated that infants who were both low in fussiness and high in predictability were at very low risk for future conduct problems. Fussiness was a stronger predictor of conduct problems in boys whereas fearfulness was a stronger predictor in girls. Conduct problems also were robustly predicted by low levels of early mother-report cognitive stimulation. Interviewer-rated maternal responsiveness was a robust predictor of conduct problems, but only among infants low in fearfulness. Spanking during infancy predicted slightly more severe conduct problems, but the prediction was moderated by infant fussiness and positive affect. Thus, individual differences in risk for mother-rated conduct problems across childhood are already partly evident in maternal ratings of temperament during the first year of life and are predicted by early parenting and parenting-by-temperament interactions. PMID:18568397
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Flexible Fabrics with High Thermal Conductivity for Advanced Spacesuits
NASA Technical Reports Server (NTRS)
Trevino, Luis A.; Bue, Grant; Orndoff, Evelyne; Kesterson, Matt; Connel, John W.; Smith, Joseph G., Jr.; Southward, Robin E.; Working, Dennis; Watson, Kent A.; Delozier, Donovan M.
2006-01-01
This paper describes the effort and accomplishments for developing flexible fabrics with high thermal conductivity (FFHTC) for spacesuits to improve thermal performance, lower weight and reduce complexity. Commercial and additional space exploration applications that require substantial performance enhancements in removal and transport of heat away from equipment as well as from the human body can benefit from this technology. Improvements in thermal conductivity were achieved through the use of modified polymers containing thermally conductive additives. The objective of the FFHTC effort is to significantly improve the thermal conductivity of the liquid cooled ventilation garment by improving the thermal conductivity of the subcomponents (i.e., fabric and plastic tubes). This paper presents the initial system modeling studies, including a detailed liquid cooling garment model incorporated into the Wissler human thermal regulatory model, to quantify the necessary improvements in thermal conductivity and garment geometries needed to affect system performance. In addition, preliminary results of thermal conductivity improvements of the polymer components of the liquid cooled ventilation garment are presented. By improving thermal garment performance, major technology drivers will be addressed for lightweight, high thermal conductivity, flexible materials for spacesuits that are strategic technical challenges of the Exploration
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Sex Differences in Autonomic Correlates of Conduct Problems and Aggression
BEAUCHAINE, THEODORE P.; HONG, JAMES; MARSH, PENNY
2009-01-01
Objective To examine sex differences in autonomic nervous system functioning in children and adolescents with conduct problems and to evaluate the role of aggression in predicting autonomic nervous system functioning, over and above the effects of disruptive behavior. Although deficiencies in autonomic responding among boys with oppositional defiant disorder and/or conduct disorder are well documented, it remains unclear whether such findings extend to girls or apply only to children with aggressive forms of conduct problems. Method Electrodermal responding, cardiac pre-ejection period, and respiratory sinus arrhythmia were recorded while boys (n = 110; 53 with conduct problems, 57 controls) and girls (n = 65; 33 with conduct problems, 32 controls) between the ages of 8 and 12 sat for an extended baseline, then played a game with conditions of reward and frustrative nonreward. Results Both sex effects and aggression effects were found. Aggressive boys with conduct problems demonstrated reduced autonomic functioning, consistent with previous research. In contrast, aggressive girls with conduct problems exhibited greater electrodermal responding than controls, with no differences in cardiovascular reactivity to incentives. Conclusions Observed sex differences in the autonomic correlates of conduct problems and aggression may suggest different etiological mechanisms of externalizing psychopathology for girls compared with boys. PMID:18520959
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Money, M K; Pippin, G W; Weaver, K E; Kirsch, J P; Webster, D B
1995-07-01
Exogenous administration of GM1 ganglioside to CBA/J mice with a neonatal conductive hearing loss ameliorates the atrophy of spiral ganglion neurons, ventral cochlear nucleus neurons, and ventral cochlear nucleus volume. The present investigation demonstrates the extent of a conductive loss caused by atresia and tests the hypothesis that GM1 ganglioside treatment will ameliorate the conductive hearing loss. Auditory brainstem responses were recorded from four groups of seven mice each: two groups received daily subcutaneous injections of saline (one group had normal hearing; the other had a conductive hearing loss); the other two groups received daily subcutaneous injections of GM1 ganglioside (one group had normal hearing; the other had a conductive hearing loss). In mice with a conductive loss, decreases in hearing sensitivity were greatest at high frequencies. The decreases were determined by comparing mean ABR thresholds of the conductive loss mice with those of normal hearing mice. The conductive hearing loss induced in the mice in this study was similar to that seen in humans with congenital aural atresias. GM1 ganglioside treatment had no significant effect on ABR wave I thresholds or latencies in either group.
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Exploring the Parameters Controlling the Crystallinity-Conductivity Correlation of PFSA Ionomers
NASA Astrophysics Data System (ADS)
Kusoglu, Ahmet; Shi, Shouwen; Weber, Adam
Perfluorosulfonic-acid (PFSA) ionomers are the most commonly used solid-electrolyte in electrochemical energy devices because of their remarkable conductivity and chemical/mechanical stability, with the latter imparted by their semi-crystalline fluorocarbon backbone. PFSAs owe this unique combination of transport/stability functionalities to their phase-separated morphology of conductive hydrophilic ionic domains and the non-conductive hydrophobic backbone, which are connected via pendant chains. Thus, phase-separation is governed by fractions of backbone and ionic groups, which is controlled by the equivalent weight (EW). Therefore, EW, along with the pendant chain chemistry, directly impact the conductive vs non-conductive regions, and consequently the interrelation between transport and stability. Driven by the need to achieve higher conductivities without disrupting the crystallinity, various pendant-chain chemistries have been developed. In this talk, we will report the results of a systematic investigation on hydration, conductivity, mechanical properties and crystallinity of various types and EWs of PFSA ionomers to (i) develop a structure/property map, and (ii) identify the key parameters controlling morphology and properties. It will be discussed how the pendant-chain and backbone lengths affect the conductivity and crystallinity, respectively. Lastly, the data set will be analyzed to explore universal structure/property relationships for PFSAs.
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Effect of electron-hole asymmetry on optical conductivity in 8 -P m m n borophene
NASA Astrophysics Data System (ADS)
Verma, Sonu; Mawrie, Alestin; Ghosh, Tarun Kanti
2017-10-01
We present a detailed theoretical study of the Drude weight and optical conductivity of 8-P m m n borophene having tilted anisotropic Dirac cones. We provide exact analytical expressions of x x and y y components of the Drude weight as well as maximum optical conductivity. We also obtain exact analytical expressions of the minimum energy (ɛ1) required to trigger the optical transitions and energy (ɛ2) needed to attain maximum optical conductivity. We find that the Drude weight and optical conductivity are highly anisotropic as a consequence of the anisotropic Dirac cone. The optical conductivities have a nonmonotonic behavior with photon energy in the regime between ɛ1 and ɛ2, as a result of the tilted parameter vt. The tilted parameter can be extracted by knowing ɛ1 and ɛ2 from optical measurements. The maximum values of the components of the optical conductivity do not depend on the carrier density and the tilted parameter. The product of the maximum values of the anisotropic conductivities has the universal value (e2/4ℏ ) 2. The tilted anisotropic Dirac cones in 8-P m m n borophene can be realized by the optical conductivity measurement.
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Wang, Jian -Jun; Wang, Yi; Ihlefeld, Jon F.; ...
2016-04-06
Effective thermal conductivity as a function of domain structure is studied by solving the heat conduction equation using a spectral iterative perturbation algorithm in materials with inhomogeneous thermal conductivity distribution. Using this proposed algorithm, the experimentally measured effective thermal conductivities of domain-engineered {001} p-BiFeO 3 thin films are quantitatively reproduced. In conjunction with two other testing examples, this proposed algorithm is proven to be an efficient tool for interpreting the relationship between the effective thermal conductivity and micro-/domain-structures. By combining this algorithm with the phase-field model of ferroelectric thin films, the effective thermal conductivity for PbZr 1-xTi xO 3 filmsmore » under different composition, thickness, strain, and working conditions is predicted. It is shown that the chemical composition, misfit strain, film thickness, film orientation, and a Piezoresponse Force Microscopy tip can be used to engineer the domain structures and tune the effective thermal conductivity. Furthermore, we expect our findings will stimulate future theoretical, experimental and engineering efforts on developing devices based on the tunable effective thermal conductivity in ferroelectric nanostructures.« less
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Gao, Nuo; Zhu, S A; He, Bin
2005-06-07
We have developed a new algorithm for magnetic resonance electrical impedance tomography (MREIT), which uses only one component of the magnetic flux density to reconstruct the electrical conductivity distribution within the body. The radial basis function (RBF) network and simplex method are used in the present approach to estimate the conductivity distribution by minimizing the errors between the 'measured' and model-predicted magnetic flux densities. Computer simulations were conducted in a realistic-geometry head model to test the feasibility of the proposed approach. Single-variable and three-variable simulations were performed to estimate the brain-skull conductivity ratio and the conductivity values of the brain, skull and scalp layers. When SNR = 15 for magnetic flux density measurements with the target skull-to-brain conductivity ratio being 1/15, the relative error (RE) between the target and estimated conductivity was 0.0737 +/- 0.0746 in the single-variable simulations. In the three-variable simulations, the RE was 0.1676 +/- 0.0317. Effects of electrode position uncertainty were also assessed by computer simulations. The present promising results suggest the feasibility of estimating important conductivity values within the head from noninvasive magnetic flux density measurements.
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NASA Astrophysics Data System (ADS)
Hort, R. D.; Revil, A.; Munakata-Marr, J.; Mao, D.
2015-07-01
Electrical resistivity measurements can potentially be used to remotely monitor fate and transport of ionic oxidants such as permanganate (MnO4-) during in situ chemical oxidation (ISCO) of contaminants like trichloroethene (TCE). Time-lapse two-dimensional bulk conductivity and induced polarization surveys conducted during a sand tank ISCO simulation demonstrated that MnO4- plume movement could be monitored in a qualitative manner using bulk conductivity tomograms, although chargeability was below sensitivity limits. We also examined changes to in-phase and quadrature electrical conductivity resulting from ion injection, MnO2 and Cl- production, and pH change during TCE and humate oxidation by MnO4- in homogeneous aqueous solutions and saturated porous media samples. Data from the homogeneous samples demonstrated that inversion of the sand tank resistivity data using a common Tikhonov regularization approach was insufficient to recover an accurate conductivity distribution within the tank. While changes to in-phase conductivity could be successfully modeled, quadrature conductivity values could not be directly related to TCE oxidation product or MnO4- concentrations at frequencies consistent with field induced polarization surveys, limiting the utility of quadrature conductivity for monitoring ISCO.
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Radin, J W; Lu, Z; Percy, R G; Zeiger, E
1994-01-01
Responses of stomata to environment have been intensively studied, but little is known of genetic effects on stomatal conductance or their consequences. In Pima cotton (Gossypium barbadense L.), a crop that is bred for irrigated production in very hot environments, stomatal conductance varies genetically over a wide range and has increased with each release of new higher-yielding cultivars. A cross between heat-adapted (high-yielding) and unadapted genotypes produced F2 progeny cosegregating for stomatal conductance and leaf temperature. Within segregating populations in the field, conductance was negatively correlated with foliar temperature because of evaporative cooling. Plants were selected from the F2 generation specifically and solely for differing stomatal conductance. Among F3 and F4 populations derived from these selections, conductance and leaf cooling were significantly correlated with fruiting prolificacy during the hottest period of the year and with yield. Conductance was not associated with other factors that might have affected yield potential (single-leaf photosynthetic rate, leaf water potential). As breeders have increased the yield of this crop, genetic variability for conductance has allowed inadvertent selection for "heat avoidance" (evaporative cooling) in a hot environment. PMID:11607487
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Jian -Jun; Wang, Yi; Ihlefeld, Jon F.
Effective thermal conductivity as a function of domain structure is studied by solving the heat conduction equation using a spectral iterative perturbation algorithm in materials with inhomogeneous thermal conductivity distribution. Using this proposed algorithm, the experimentally measured effective thermal conductivities of domain-engineered {001} p-BiFeO 3 thin films are quantitatively reproduced. In conjunction with two other testing examples, this proposed algorithm is proven to be an efficient tool for interpreting the relationship between the effective thermal conductivity and micro-/domain-structures. By combining this algorithm with the phase-field model of ferroelectric thin films, the effective thermal conductivity for PbZr 1-xTi xO 3 filmsmore » under different composition, thickness, strain, and working conditions is predicted. It is shown that the chemical composition, misfit strain, film thickness, film orientation, and a Piezoresponse Force Microscopy tip can be used to engineer the domain structures and tune the effective thermal conductivity. Furthermore, we expect our findings will stimulate future theoretical, experimental and engineering efforts on developing devices based on the tunable effective thermal conductivity in ferroelectric nanostructures.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Xiaoguang; McGuire, Michael A.; Chen, Yong P.
Topological insulators, with characteristic topological surface states, have emerged as a new state of matter with rich potentials for both fundamental physics and device applications. However, the experimental detection of the surface transport has been hampered by the unavoidable extrinsic conductivity associated with the bulk crystals. Here we show that a four-probe transport spectroscopy in a multi-probe scanning tunneling microscopy system can be used to differentiate conductivities from the surface states and the coexisting bulk states in topological insulators. We derive a scaling relation of measured resistance with respect to varying inter-probe spacing for two interconnected conduction channels, which allowsmore » quantitative determination of conductivities from both channels. Using this method, we demonstrate the separation of 2D and 3D conduction in topological insulators by comparing the conductance scaling of Bi 2Se 3, Bi 2Te 2Se, and Sb-doped Bi 2Se 3 with that of a pure 2D conductance of graphene on SiC substrate. We also report the 2D conductance enhancement due to the surface doping effect in topological insulators. This technique can be applied to reveal 2D to 3D crossover of conductance in other complex systems.« less
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49 CFR 237.107 - Conduct of bridge inspections.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Conduct of bridge inspections. 237.107 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.107 Conduct of bridge inspections. Bridge inspections shall be conducted under the direct supervision of a designated...
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16 CFR 1025.66 - Qualifications and standards of conduct.
Code of Federal Regulations, 2011 CFR
2011-01-01
... standards of conduct. (a) Good faith transactions. The Commission expects all persons appearing in... conducted in good faith. (b) Exclusion of parties, participants, or their representatives. To maintain... reasonable standards of orderly and ethical conduct, failure to act in good faith, or violation of the...
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Organic conductive films for semiconductor electrodes
Frank, A.J.
1984-01-01
According to the present invention, improved electrodes overcoated with conductive polymer films and preselected catalysts are provided. The electrodes typically comprise an inorganic semiconductor over-coated with a charge conductive polymer film comprising a charge conductive polymer in or on which is a catalyst or charge-relaying agent.
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7 CFR 3022.5 - Reservation of right to conduct subsequent inquiry, investigation, and adjudication.
Code of Federal Regulations, 2011 CFR
2011-01-01
... USDA-FUNDED EXTRAMURAL RESEARCH; RESEARCH MISCONDUCT § 3022.5 Reservation of right to conduct..., investigation, and adjudication into allegations of research misconduct at a research institution conducting... research misconduct procedures in place, the research institution conducting the extramural research at...
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7 CFR 3022.5 - Reservation of right to conduct subsequent inquiry, investigation, and adjudication.
Code of Federal Regulations, 2012 CFR
2012-01-01
... USDA-FUNDED EXTRAMURAL RESEARCH; RESEARCH MISCONDUCT § 3022.5 Reservation of right to conduct..., investigation, and adjudication into allegations of research misconduct at a research institution conducting... research misconduct procedures in place, the research institution conducting the extramural research at...
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18 CFR 5.15 - Conduct of studies.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Conduct of studies. 5... Conduct of studies. (a) Implementation. The potential applicant must gather information and conduct studies as provided for in the approved study plan and schedule. (b) Progress reports. The potential...
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18 CFR 5.15 - Conduct of studies.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Conduct of studies. 5... Conduct of studies. (a) Implementation. The potential applicant must gather information and conduct studies as provided for in the approved study plan and schedule. (b) Progress reports. The potential...
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21 CFR 868.5130 - Anesthesia conduction filter.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Anesthesia conduction filter. 868.5130 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5130 Anesthesia conduction filter. (a) Identification. An anesthesia conduction filter is a microporous filter used while administering to a patient...
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21 CFR 868.5130 - Anesthesia conduction filter.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Anesthesia conduction filter. 868.5130 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5130 Anesthesia conduction filter. (a) Identification. An anesthesia conduction filter is a microporous filter used while administering to a patient...
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21 CFR 868.5130 - Anesthesia conduction filter.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Anesthesia conduction filter. 868.5130 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5130 Anesthesia conduction filter. (a) Identification. An anesthesia conduction filter is a microporous filter used while administering to a patient...
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21 CFR 868.5130 - Anesthesia conduction filter.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Anesthesia conduction filter. 868.5130 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5130 Anesthesia conduction filter. (a) Identification. An anesthesia conduction filter is a microporous filter used while administering to a patient...
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21 CFR 868.5130 - Anesthesia conduction filter.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Anesthesia conduction filter. 868.5130 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5130 Anesthesia conduction filter. (a) Identification. An anesthesia conduction filter is a microporous filter used while administering to a patient...
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23 CFR 627.9 - Conducting a VE analysis.
Code of Federal Regulations, 2014 CFR
2014-04-01
... FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS VALUE ENGINEERING § 627.9 Conducting a VE analysis. (a) A VE analysis should be conducted as early as practicable in... that consider alternative construction materials; and (2) Be conducted based on: (i) An engineering and...
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23 CFR 627.9 - Conducting a VE analysis.
Code of Federal Regulations, 2013 CFR
2013-04-01
... FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS VALUE ENGINEERING § 627.9 Conducting a VE analysis. (a) A VE analysis should be conducted as early as practicable in... that consider alternative construction materials; and (2) Be conducted based on: (i) An engineering and...
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13 CFR 105.402 - Standards of Conduct Counselors.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Standards of Conduct Counselors. 105.402 Section 105.402 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION STANDARDS OF... Conduct Counselors. (a) The SBA Standards of Conduct Counselor is the Designated Agency Ethics Official...
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Shrink-wrapping water to conduct protons
NASA Astrophysics Data System (ADS)
Shimizu, George K. H.
2017-11-01
For proton-conducting metal-organic frameworks (MOFs) to find application as the electrolyte in proton-exchange membrane fuel cells, materials with better stability and conductivity are required. Now, a structurally flexible MOF that is also highly stable is demonstrated to possess high proton conductivity over a range of humidities.
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Pin-deposition of conductive inks for microelectrodes and contact via filling
Davidson, J. Courtney; Krulevitch, Peter A.; Maghribi, Mariam N.; Hamilton, Julie K.; Benett, William J.; Tovar, Armando R.
2006-05-02
A method of metalization of an integrated microsystem. The method comprises providing a substrate and applying a conductive material to the substrate by taking up small aliquots of conductive material and releasing the conductive material onto the substrate to produce a circuit component.
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49 CFR 237.107 - Conduct of bridge inspections.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Conduct of bridge inspections. 237.107 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.107 Conduct of bridge inspections. Bridge inspections shall be conducted under the direct supervision of a designated...
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Thermal Analysis of Filler Reinforced Polymeric Composites
NASA Astrophysics Data System (ADS)
Ghadge, Mahesh Devidas
Improving heat dissipating property of composite materials is becoming increasingly important in domains ranging from the automotive industry, electronic devices to aeronautical industry. Effective heat dissipation is required especially in aircraft and racing tires to guarantee high performance and good service life [1]. The present study is focused on improving the thermal conductivity of Emulsion-styrene butadiene rubber (ESBR) which is a cheap alternative to other rubber composites. The disadvantages of ESBR are low thermal conductivity and high heat generation. Adding fillers with high thermal conductivity to ESBR is proposed as a technique for improving the thermal conductivity of ESBR. The purpose of the research is to predict the thermal conductivity of ESBR when filled with fillers of much higher thermal conductivity and also to find out to what extent the filler properties affect the heat transfer capabilities of the composite matrix. The influence of different filler shapes i.e. spherical, cylindrical and platelets on the overall thermal capability of composite matrix is studied, the finite element modelings are conducted using Abaqus. Three-dimensional and two-dimensional models are created in Abaqus to simulate the microstructure of the composite matrix filled with fillers. Results indicate that the overall thermal conductivity increases with increasing filler loading i.e. for a filler volume fraction of 0.27, the conductivity increased by around 50%. Filler shapes, orientation angle, and aspect ratio of the fillers significantly influences the thermal conductivity. Conductivity increases with increasing aspect ratio (length/diameter) of the cylindrical fillers since longer conductive chains are able to form at the same volume percentage as compared to spherical fillers. The composite matrix reaches maximum thermal conductivity when the cylindrical fillers are oriented in the direction of heat flow. The heat conductivity predicted by FEM for ESBR is compared with that predicted by mean field theories. At low volume fractions the FEM and mean field theory results are matching. However, at high volume fractions, the results obtained by the two methods are not in agreement. This is due to the fact that mean field theory do not consider the particle interactions happening at higher volume fractions. The present analysis can be used to tailor the thermal properties of ESBR for required thermal conductivity for a wide range of applications such as racing tires, electronic gadgets or aeronautical components. In addition, the proposed FEM models can be used to design and optimize the properties of new composite materials providing more insight into the thermal conductivity of composite polymers and aid in understanding heat transfer mechanism of reinforced polymers.
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Nonlinear dynamics in cardiac conduction
NASA Technical Reports Server (NTRS)
Kaplan, D. T.; Smith, J. M.; Saxberg, B. E.; Cohen, R. J.
1988-01-01
Electrical conduction in the heart shows many phenomena familiar from nonlinear dynamics. Among these phenomena are multiple basins of attraction, phase locking, and perhaps period-doubling bifurcations and chaos. We describe a simple cellular-automation model of electrical conduction which simulates normal conduction patterns in the heart as well as a wide range of disturbances of heart rhythm. In addition, we review the application of percolation theory to the analysis of the development of complex, self-sustaining conduction patterns.
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Electrically conductive cellulose composite
Evans, Barbara R.; O'Neill, Hugh M.; Woodward, Jonathan
2010-05-04
An electrically conductive cellulose composite includes a cellulose matrix and an electrically conductive carbonaceous material incorporated into the cellulose matrix. The electrical conductivity of the cellulose composite is at least 10 .mu.S/cm at 25.degree. C. The composite can be made by incorporating the electrically conductive carbonaceous material into a culture medium with a cellulose-producing organism, such as Gluconoacetobacter hansenii. The composites can be used to form electrodes, such as for use in membrane electrode assemblies for fuel cells.
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Gene Regulatory Networks in Cardiac Conduction System Development
Munshi, Nikhil V.
2014-01-01
The cardiac conduction system is a specialized tract of myocardial cells responsible for maintaining normal cardiac rhythm. Given its critical role in coordinating cardiac performance, a detailed analysis of the molecular mechanisms underlying conduction system formation should inform our understanding of arrhythmia pathophysiology and affect the development of novel therapeutic strategies. Historically, the ability to distinguish cells of the conduction system from neighboring working myocytes presented a major technical challenge for performing comprehensive mechanistic studies. Early lineage tracing experiments suggested that conduction cells derive from cardiomyocyte precursors, and these claims have been substantiated by using more contemporary approaches. However, regional specialization of conduction cells adds an additional layer of complexity to this system, and it appears that different components of the conduction system utilize unique modes of developmental formation. The identification of numerous transcription factors and their downstream target genes involved in regional differentiation of the conduction system has provided insight into how lineage commitment is achieved. Furthermore, by adopting cutting-edge genetic techniques in combination with sophisticated phenotyping capabilities, investigators have made substantial progress in delineating the regulatory networks that orchestrate conduction system formation and their role in cardiac rhythm and physiology. This review describes the connectivity of these gene regulatory networks in cardiac conduction system development and discusses how they provide a foundation for understanding normal and pathological human cardiac rhythms. PMID:22628576
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NASA Astrophysics Data System (ADS)
Lombardozzi, D.; Levis, S.; Bonan, G.; Sparks, J. P.
2012-08-01
Plants exchange greenhouse gases carbon dioxide and water with the atmosphere through the processes of photosynthesis and transpiration, making them essential in climate regulation. Carbon dioxide and water exchange are typically coupled through the control of stomatal conductance, and the parameterization in many models often predict conductance based on photosynthesis values. Some environmental conditions, like exposure to high ozone (O3) concentrations, alter photosynthesis independent of stomatal conductance, so models that couple these processes cannot accurately predict both. The goals of this study were to test direct and indirect photosynthesis and stomatal conductance modifications based on O3 damage to tulip poplar (Liriodendron tulipifera) in a coupled Farquhar/Ball-Berry model. The same modifications were then tested in the Community Land Model (CLM) to determine the impacts on gross primary productivity (GPP) and transpiration at a constant O3 concentration of 100 parts per billion (ppb). Modifying the Vcmax parameter and directly modifying stomatal conductance best predicts photosynthesis and stomatal conductance responses to chronic O3 over a range of environmental conditions. On a global scale, directly modifying conductance reduces the effect of O3 on both transpiration and GPP compared to indirectly modifying conductance, particularly in the tropics. The results of this study suggest that independently modifying stomatal conductance can improve the ability of models to predict hydrologic cycling, and therefore improve future climate predictions.
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Anisotropy of synthetic quartz electrical conductivity at high pressure and temperature
NASA Astrophysics Data System (ADS)
Wang, Duojun; Li, Heping; Yi, Li; Matsuzaki, Takuya; Yoshino, Takashi
2010-09-01
AC measurements of the electrical conductivity of synthetic quartz along various orientations were made between 0.1 and 1 MHz, at ˜855˜1601 K and at 1.0 GPa. In addition, the electrical conductivity of quartz along the c axis has been studied at 1.0-3.0 GPa. The impedance arcs representing bulk conductivity occur in the frequency range of 103-106 Hz, and the electrical responses of the interface between the sample and the electrode occur in the 0.1˜103 Hz range. The pressure has a weak effect on the electrical conductivity. The electrical conductivity experiences no abrupt change near the α - β phase transition point. The electrical conductivity of quartz is highly anisotropic; the electrical conductivity along the c axis is strongest and several orders of magnitude larger than in other directions. The activation enthalpies along various orientations are determined to be 0.6 and 1.2 eV orders of magnitude, respectively. The interpretation of the former is based on the contribution of alkali ions, while the latter effect is attributed to additional unassociated aluminum ions. Comparison of determined anisotropic conductivity of quartz determined with those from field geophysical models shows that the quartz may potentially provide explanations for the behavior of electrical conductivity of anisotropy in the crust that are inferred from the transverse magnetic mode.
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Vaddiraju, Sreeram; Cebeci, Hülya; Gleason, Karen K; Wardle, Brian L
2009-11-01
A novel method for the fabrication of carbon nanotube (CNT)-conducting polymer composites is demonstrated by conformally coating extremely high aspect ratio vertically aligned-CNT (A-CNT) arrays with conducting polymer via oxidative chemical vapor deposition (oCVD). A mechanical densification technique is employed that allows the spacing of the A-CNTs to be controlled, yielding a range of inter-CNT distances between 20 and 70 nm. Using this morphology control, oCVD is shown to conformally coat 8-nm-diameter CNTs having array heights up to 1 mm (an aspect ratio of 10(5)) at all inter-CNT spacings. Three phase CNT-conducting polymer nanocomposites are then fabricated by introducing an insulating epoxy via capillary-driven wetting. CNT morphology is maintained during processing, allowing quantification of direction-dependent (nonisotropic) composite properties. Electrical conductivity occurs primarily along the CNT axial direction, such that the conformal conducting polymer has little effect on the activation energy required for charge conduction. In contrast, the conducting polymer coating enhanced the conductivity in the radial direction by lowering the activation energy required for the creation of mobile charge carriers, in agreement with variable-range-hopping models. The fabrication strategy introduced here can be used to create many multifunctional materials and devices (e.g., direction-tailorable hydrophobic and highly conducting materials), including a new four-phase advanced fiber composite architecture.
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NASA Astrophysics Data System (ADS)
Zhong, Haoxiang; He, Aiqin; Lu, Jidian; Sun, Minghao; He, Jiarong; Zhang, Lingzhi
2016-12-01
A water-soluble conductive composite binder consisting of carboxymethyl chitosan (CCTS) as a binder and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as a conduction-promoting agent is reported for the LiFePO4 (LFP) cathode in Li-ion batteries. The introduction of conductive PEDOT:PSS as a conductive composite binder facilitates the formation of homogeneous and continuous conducting bridges throughout the electrode and raises the compaction density of the electrode sheet by decreasing the amounts of the commonly used conducting agent of acetylene black. The optimized replacement ratios of acetylene black with PEDOT:PSS (acetylene black/PEDOT:PSS = 1:1, by weight) are obtained by measuring electrical conductivity, peel strength and compaction density of the electrode sheets. The LFP half-cell with the optimized conductive binder exhibits better cycling and rate performance and more favorable electrochemical kinetics than that using only acetylene black conducting agent. The pilot application of PEDOT:PSS/CCTS binder in 10 Ah CCTS-LFP prismatic cell exhibits a comparable cycling performance, retaining 89.7% of capacity at 1 C/2 C (charge/discharge) rate as compared with 90% for commercial PVDF-LFP over 1000 cycles, and better rate capability than that of commercial PVDF-LFP, retaining 98% capacity of 1 C at 7 C rate as compared with 95.4% for PVDF-LFP.
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Grillet, Anne M.; Humplik, Thomas; Stirrup, Emily K.; ...
2016-07-02
The polymer-composite binder used in lithium-ion battery electrodes must both hold the electrodes together and augment their electrical conductivity while subjected to mechanical stresses caused by active material volume changes due to lithiation and delithiation. We have discovered that cyclic mechanical stresses cause significant degradation in the binder electrical conductivity. After just 160 mechanical cycles, the conductivity of polyvinylidene fluoride (PVDF):carbon black binder dropped between 45–75%. This degradation in binder conductivity has been shown to be quite general, occurring over a range of carbon black concentrations, with and without absorbed electrolyte solvent and for different polymer manufacturers. Mechanical cycling ofmore » lithium cobalt oxide (LiCoO2) cathodes caused a similar degradation, reducing the effective electrical conductivity by 30–40%. Mesoscale simulations on a reconstructed experimental cathode geometry predicted the binder conductivity degradation will have a proportional impact on cathode electrical conductivity, in qualitative agreement with the experimental measurements. Lastly, ohmic resistance measurements were made on complete batteries. Direct comparisons between electrochemical cycling and mechanical cycling show consistent trends in the conductivity decline. This evidence supports a new mechanism for performance decline of rechargeable lithium-ion batteries during operation – electrochemically-induced mechanical stresses that degrade binder conductivity, increasing the internal resistance of the battery with cycling.« less
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Li, Zhiyong; Yuan, Xiaoqing; Feng, Ying; Chen, Yongkui; Zhao, Yuling; Wang, Huiyong; Xu, Qingli; Wang, Jianji
2018-05-09
Photo-induced conductivity modulation of stimuli-responsive materials is of great importance from the viewpoint of fundamental research and technology. In this work, 5 new kinds of azobenzene-based photo-responsive ionic liquids were synthesized and characterized, and UV/vis light modulation of their conductivity was investigated in an aqueous solution. The factors affecting the conductivity modulation of the photo-responsive fluids, such as photo-isomerization efficiency, photo-regulation aggregation, concentration and chemical structure of the ionic liquids, were examined systematically. It was found that the conductivity of the ionic liquids in water exhibited a significant increase upon UV light irradiation and the ionic liquids with a shorter alkyl spacer in the cation showed a more remarkable photo-induced conductivity enhancement with a maximum increase of 150%. In addition, the solution conductivity was restored (or very close) to the initial value upon an alternative irradiation with visible light. Thus, the solution conductivity can be modulated using alternative irradiation with UV and visible light. Although the reversible photo-isomerization of the azobenzene group under UV/vis irradiation is the origin of the conductivity modulation, the photo-regulated aggregation of the ionic liquid in water is indispensable for the maximum degree of conductivity modulation because UV irradiation can weaken, even break the aggregated cis-isomers of the ionic liquids in an aqueous solution.
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Data Transmission System For A Downhole Component
Hall, David R.; Hall, Jr., H. Tracy; Pixton, David; Dahlgren, Scott; Sneddon, Cameron; Fox, Joe; Briscoe, Michael
2005-01-18
The invention is a system for transmitting data through a string of downhole components. In accordance with one aspect of the invention, the system includes a plurality of downhole components, such as sections of pipe in a drill string. Each component has a first and second end, with a first communication element located at the first end and a second communication element located at the second end. Each communication element includes a first contact and a second contact. The system also includes a coaxial cable running between the first and second communication elements, the coaxial cable having a conductive tube and a conductive core within it. The system also includes a first and second connector for connecting the first and second communication elements respectively to the coaxial cable. Each connector includes a conductive sleeve, lying concentrically within the conductive tube, which fits around and makes electrical contact with the conductive core. The conductive sleeve is electrically isolated from the conductive tube. The conductive sleeve of the first connector is in electrical contact with the first contact of the first communication element, the conductive sleeve of the second connector is in electrical contact with the first contact of the second communication element, and the conductive tube is in electrical contact with both the second contact of the first communication element and the second contact of the second communication element.
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Data transmission system for a downhole component
Hall, David R.; Hall, Jr., Tracy H.; Pixton, David S.; Dahlgren, Scott Steven; Fox, Joe; Sneddon, Cameron; Briscoe, Michael A.
2006-05-09
The invention is a system for transmitting data through a string of downhole components. In accordance with one aspect of the invention, the system includes a plurality of downhole components, such as sections of pipe in a drill string. Each component has a first and second end, with a first communication element located at the first end and a second communication element located at the second end. Each communication element includes a first contact and a second contact. The system also includes a coaxial cable running between the first and second communication elements, the coaxial cable having a conductive tube and a conductive core within it. The system also includes a first and second connector for connecting the first and second communication elements respectively to the coaxial cable. Each connector includes a conductive sleeve, lying concentrically within the conductive tube, which fits around and makes electrical contact with the conductive core. The conductive sleeve is electrically isolated from the conductive tube. The conductive sleeve of the first connector is in electrical contact with the first contact of the first communication element, the conductive sleeve of the second connector is in electrical contact with the first contact of the second communication element, and the conductive tube is in electrical contact with both the second contact of the first communication element and the second contact of the second communication element.
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NASA Astrophysics Data System (ADS)
Hanif, M. P. M.; Supri, A. G.; Rozyanty, A. R.; Tan, S. J.
2017-10-01
The wood fiber (WF) type of Pulverised Wood Filler obtained by combustion process at temperature under 700 °C for 3 hours was characterized and coated with ferric chloride (FeCl3) by ethanol solution. Both carbonized wood fiber (CWF) and carbonized wood fiber-ferric chloride (CWF-FeCl3) were used as filler in ethylene vinyl acetate (EVA) conductive polymer. The filler was coated with FeCl3 to enhance the properties of the CWF to achieve progressive mechanical and electrical properties. The CWF and CWF-FeCl3 loading were varied from 2.5 to 10.0 wt%. EVA/CWF and EVA/CWF-FeCl3 conductive polymer were processed by using Brabender Plasticoder at 160 °C with 50 rpm rotor speed for 10 min. The mechanical properties were investigated by tensile testing and the tensile fractured surface of conductive polymers was analyzed by scanning electron microscopy (SEM) analysis. Then, the electrical conductivity of conductive polymer was determined by four-point probe I-V measurement system. The EVA/CWF-FeCl3 conductive polymer showed greater electrical conductivity and tensile strength but lower elongation at break than EVA/CWF conductive polymer. SEM morphology displayed rougher surface between CWF-FeCl3 and EVA phases compared to EVA/CWF conductive polymer.
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Carbon nanomaterials used as conductive additives in lithium ion batteries.
Zhang, Qingtang; Yu, Zuolong; Du, Ping; Su, Ce
2010-06-01
As the vital part of lithium ion batteries, conductive additives play important roles in the electrochemical performance of lithium ion batteries. They construct a conductive percolation network to increase and keep the electronic conductivity of electrode, enabling it charge and discharge faster. In addition, conductive additives absorb and retain electrolyte, allowing an intimate contact between the lithium ions and active materials. Carbon nanomaterials are carbon black, Super P, acetylene black, carbon nanofibers, and carbon nanotubes, which all have superior properties such as low weight, high chemical inertia and high specific surface area. They are the ideal conductive additives for lithium ion batteries. This review will discuss some registered patents and relevant papers about the carbon nanomaterials that are used as conductive additives in cathode or anode to improve the electrochemical performance of lithium ion batteries.
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Bessaire, Bastien; Mathieu, Maillard; Salles, Vincent; Yeghoyan, Taguhi; Celle, Caroline; Simonato, Jean-Pierre; Brioude, Arnaud
2017-01-11
A process to synthesize continuous conducting nanofibers were developed using PEDOT:PSS as a conducting polymer and an electrospinning method. Experimental parameters were carefully explored to achieve reproducible conductive nanofibers synthesis in large quantities. In particular, relative humidity during the electrospinning process was proven to be of critical importance, as well as doping post-treatment involving glycols and alcohols. The synthesized fibers were assembled as a mat on glass substrates, forming a conductive and transparent electrode and their optoelectronic have been fully characterized. This method produces a conformable conductive and transparent coating that is well-adapted to nonplanar surfaces, having very large aspect ratio features. A demonstration of this property was made using surfaces having deep trenches and high steps, where conventional transparent conductive materials fail because of a lack of conformability.
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Anti-resonance scattering at defect levels in the quantum conductance of a one-dimensional system
NASA Astrophysics Data System (ADS)
Sun, Z. Z.; Wang, Y. P.; Wang, X. R.
2002-03-01
For the ballistic quantum transport, the conductance of one channel is quantized to a value of 2e^2/h described by the Landauer formula. In the presence of defects, electrons will be scattered by these defects. Thus the conductance will deviate from the values of the quantized conductance. We show that an anti-resonance scattering can occur when an extra defect level is introduced into a conduction band. At the anti-resonance scattering, exact one quantum conductance is destroyed. The conductance takes a non-zero value when the Fermi energy is away from the anti-resonance scattering. The result is consistent with recent numerical calculations given by H. J. Choi et al. (Phys. Rev. Lett. 84, 2917(2000)) and P. L. McEuen et al. (Phys. Rev. Lett. 83, 5098(1999)).
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Cylindrical Asymmetrical Capacitor Devices for Space Applications
NASA Technical Reports Server (NTRS)
Campbell, Jonathan W. (Inventor)
2004-01-01
An asymmetrical capacitor system is provided which creates a thrust force. The system is adapted for use in space applications and includes a capacitor device provided with a first conductive element and a second conductive element axially spaced from the first conductive element and of smaller axial extent. A shroud supplied with gas surrounds the capacitor device. The second conductive element can be a wire ring or mesh mounted on dielectric support posts affixed to a dielectric member which separates the conductive elements or a wire or mesh annulus surrounding a barrel-shaped dielectric member on which the h t element is also mounted. A high voltage source is connected across the conductive elements and applies a high voltage to the conductive elements of sufficient value to create a thrust force on the system inducing movement thereof.
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Ballistic and Diffusive Thermal Conductivity of Graphene
NASA Astrophysics Data System (ADS)
Saito, Riichiro; Masashi, Mizuno; Dresselhaus, Mildred S.
2018-02-01
This paper is a contribution to the Physical Review Applied collection in memory of Mildred S. Dresselhaus. Phonon-related thermal conductivity of graphene is calculated as a function of the temperature and sample size of graphene in which the crossover of ballistic and diffusive thermal conductivity occurs at around 100 K. The diffusive thermal conductivity of graphene is evaluated by calculating the phonon mean free path for each phonon mode in which the anharmonicity of a phonon and the phonon scattering by a 13C isotope are taken into account. We show that phonon-phonon scattering of out-of-plane acoustic phonon by the anharmonic potential is essential for the largest thermal conductivity. Using the calculated results, we can design the optimum sample size, which gives the largest thermal conductivity at a given temperature for applying thermal conducting devices.
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Using electrical impedance tomography to map subsurface hydraulic conductivity
Berryman, James G.; Daily, William D.; Ramirez, Abelardo L.; Roberts, Jeffery J.
2000-01-01
The use of Electrical Impedance Tomography (EIT) to map subsurface hydraulic conductivity. EIT can be used to map hydraulic conductivity in the subsurface where measurements of both amplitude and phase are made. Hydraulic conductivity depends on at least two parameters: porosity and a length scale parameter. Electrical Resistance Tomography (ERT) measures and maps electrical conductivity (which can be related to porosity) in three dimensions. By introducing phase measurements along with amplitude, the desired additional measurement of a pertinent length scale can be achieved. Hydraulic conductivity controls the ability to flush unwanted fluid contaminants from the surface. Thus inexpensive maps of hydraulic conductivity would improve planning strategies for subsequent remediation efforts. Fluid permeability is also of importance for oil field exploitation and thus detailed knowledge of fluid permeability distribution in three-dimension (3-D) would be a great boon to petroleum reservoir analysts.
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Tuning thermal conductivity in molybdenum disulfide by electrochemical intercalation
Zhu, Gaohua; Liu, Jun; Zheng, Qiye; Zhang, Ruigang; Li, Dongyao; Banerjee, Debasish; Cahill, David G.
2016-01-01
Thermal conductivity of two-dimensional (2D) materials is of interest for energy storage, nanoelectronics and optoelectronics. Here, we report that the thermal conductivity of molybdenum disulfide can be modified by electrochemical intercalation. We observe distinct behaviour for thin films with vertically aligned basal planes and natural bulk crystals with basal planes aligned parallel to the surface. The thermal conductivity is measured as a function of the degree of lithiation, using time-domain thermoreflectance. The change of thermal conductivity correlates with the lithiation-induced structural and compositional disorder. We further show that the ratio of the in-plane to through-plane thermal conductivity of bulk crystal is enhanced by the disorder. These results suggest that stacking disorder and mixture of phases is an effective mechanism to modify the anisotropic thermal conductivity of 2D materials. PMID:27767030
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Aithal, Sreedevi; Aithal, Venkatesh; Kei, Joseph; Driscoll, Carlie
2012-10-01
Although newborn hearing screening programs have been introduced in most states in Australia, the prevalence of conductive hearing loss and middle ear pathology in the infants referred through these programs is not known. This study was designed to (1) evaluate the prevalence of conductive hearing loss and middle ear pathology in infants referred by a newborn hearing screening program in north Queensland, (2) compare prevalence rates of conductive hearing loss and middle ear pathology in indigenous and nonindigenous infants, and (3) review the outcomes of those infants diagnosed with conductive hearing loss and middle ear pathology. Retrospective chart review of infants referred to the Audiology Department of The Townsville Hospital was conducted. Chart review of 234 infants referred for one or both ears from a newborn hearing screening program in north Queensland was conducted. A total of 211 infants attended the diagnostic appointment. Review appointments to monitor hearing status were completed for 46 infants with middle ear pathology or conductive hearing loss. Diagnosis of hearing impairment was made using an age-appropriate battery of audiological tests. Results were analyzed for both initial and review appointments. Mean age at initial diagnostic assessment was 47.5 days (SD = 31.3). Of the 69 infants with middle ear pathology during initial diagnostic assessment, 18 had middle ear pathology with normal hearing, 47 had conductive hearing loss, and 4 had mixed hearing loss. Prevalence of conductive hearing loss in the newborns was 2.97 per 1,000 while prevalence of middle ear pathology (with or without conductive hearing loss) was 4.36 per 1,000. Indigenous Australians or Aboriginal and Torres Strait Islander (ATSI) infants had a significantly higher prevalence of conductive hearing loss and middle ear pathology than non-ATSI infants (35.19 and 44.45% vs 17.83 and 28.66%, respectively). ATSI infants also showed poor resolution of conductive hearing loss over time with 66.67% of ATSI infants reviewed showing persistent conductive hearing loss compared to 17.86% of non-ATSI infants. Medical management of 17 infants with persistent conductive hearing loss included monitoring, antibiotic treatment, examination under anesthesia, and grommet insertion. Conductive hearing loss was found to be a common diagnosis among infants referred through screening. ATSI infants had significantly higher rates of middle ear pathology and conductive hearing loss at birth and showed poor resolution of middle ear pathology over time compared to non-ATSI infants. Future research using a direct measure of middle ear function as an adjunct to the automated auditory brainstem response screening tool to distinguish conductive from sensorineural hearing loss may facilitate prioritization of infants for assessment, thus reducing parental anxiety and streamlining the management strategies for the respective types of hearing loss. American Academy of Audiology.
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Induced polarization of volcanic rocks - 1. Surface versus quadrature conductivity
NASA Astrophysics Data System (ADS)
Revil, A.; Le Breton, M.; Niu, Q.; Wallin, E.; Haskins, E.; Thomas, D. M.
2017-02-01
We performed complex conductivity measurements on 28 core samples from the hole drilled for the Humu'ula Groundwater Research Project (Hawai'i Island, HI, USA). The complex conductivity measurements were performed at 4 different pore water conductivities (0.07, 0.5, 1.0 or 2.0, and 10 S m-1 prepared with NaCl) over the frequency range 1 mHz to 45 kHz at 22 ± 1 °C. The in-phase conductivity data are plotted against the pore water conductivity to determine, sample by sample, the intrinsic formation factor and the surface conductivity. The intrinsic formation factor is related to porosity by Archie's law with an average value of the cementation exponent m of 2.45, indicating that only a small fraction of the connected pore space controls the transport properties. Both the surface and quadrature conductivities are found to be linearly related to the cation exchange capacity of the material, which was measured with the cobalt hexamine chloride method. Surface and quadrature conductivities are found to be proportional to each other like for sedimentary siliclastic rocks. A Stern layer polarization model is used to explain these experimental results. Despite the fact that the samples contain some magnetite (up to 5 per cent wt.), we were not able to identify the effect of this mineral on the complex conductivity spectra. These results are very encouraging in showing that galvanometric induced polarization measurements can be used in volcanic areas to separate the bulk from the surface conductivity and therefore to define some alteration attributes. Such a goal cannot be achieved with resistivity alone.
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Lin, Frank S; Ip, James E; Markowitz, Steven M; Liu, Christopher F; Thomas, George; Lerman, Bruce B; Cheung, Jim W
2015-05-01
Adenosine (ADO) can uncover dormant conduction following pulmonary vein (PV) isolation. We sought to identify the value of dormant conduction for predicting atrial fibrillation (AF) recurrence and chronic PV reconnection. One hundred fifty-two patients (80 male; age 60 ± 11 years) undergoing PV isolation for AF were studied. After PV isolation, sites of ADO-induced PV reconnection were recorded and targeted with additional ablation. In patients undergoing repeat ablation for recurrent AF, chronic PV reconnection was assessed. Forty-five (30%) patients had ADO-induced PV reconnection following PV isolation. Dormant conduction was successfully eliminated with additional ablation in 41 (91%) of these patients. After follow-up of 598 ± 270 days, 60 (39%) patients had recurrent AF. Dormant PV conduction was not a significant predictor of AF recurrence (hazard ratio 1.51; 95% confidence interval: 0.89-2.56; P = 0.12) although three of four (75%) patients with residual dormant conduction following initial ablation developed recurrent AF. Twenty-six patients with recurrent AF underwent repeat ablation with 52 of 99 (53%) PVs found to have chronic reconnection. Nine of 11 (82%) PVs with dormant conduction and 43 of 88 (49%) PVs without dormant conduction at initial procedure had chronic reconnection at repeat ablation. When additional ablation is performed to eliminate ADO-induced PV reconnection after PV isolation, dormant conduction is not a significant predictor of recurrent AF. Although PVs with dormant conduction at initial procedure may develop chronic reconnection, the majority of PVs that show conduction recovery at repeat ablation occur in nondormant PVs. © 2015 Wiley Periodicals, Inc.
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Heat, chloride, and specific conductance as ground water tracers near streams
Cox, M.H.; Su, G.W.; Constantz, J.
2007-01-01
Commonly measured water quality parameters were compared to heat as tracers of stream water exchange with ground water. Temperature, specific conductance, and chloride were sampled at various frequencies in the stream and adjacent wells over a 2-year period. Strong seasonal variations in stream water were observed for temperature and specific conductance. In observation wells where the temperature response correlated to stream water, chloride and specific conductance values were similar to stream water values as well, indicating significant stream water exchange with ground water. At sites where ground water temperature fluctuations were negligible, chloride and/or specific conductance values did not correlate to stream water values, indicating that ground water was not significantly influenced by exchange with stream water. Best-fit simulation modeling was performed at two sites to derive temperature-based estimates of hydraulic conductivities of the alluvial sediments between the stream and wells. These estimates were used in solute transport simulations for a comparison of measured and simulated values for chloride and specific conductance. Simulation results showed that hydraulic conductivities vary seasonally and annually. This variability was a result of seasonal changes in temperature-dependent hydraulic conductivity and scouring or clogging of the streambed. Specific conductance fits were good, while chloride data were difficult to fit due to the infrequent (quarterly) stream water chloride measurements during the study period. Combined analyses of temperature, chloride, and specific conductance led to improved quantification of the spatial and temporal variability of stream water exchange with shallow ground water in an alluvial system. ?? 2007 National Ground Water Association.
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P-Type Transparent Cu-Alloyed ZnS Deposited at Room Temperature
Woods-Robinson, Rachel; Cooper, Jason K.; Xu, Xiaojie; ...
2016-03-16
All transparent conducting materials (TCMs) of technological practicality are n-type; the inferior conductivity of p-type TCMs has limited their adoption. Additionally, many relatively high-performing p-type TCMs require synthesis temperatures > 400 °C. Here, room-temperature pulsed laser deposition of copper-alloyed zinc sulfide (Cu x Zn 1- x S) thin films (0 ≤ x ≤ 0.75) is reported. For 0.09 ≤ x ≤ 0.35, Cu x Zn 1- x S has high p-type conductivity, up to 42 S cm -1 at x = 0.30, with an optical band gap tunable from ≈3.0–3.3 eV and transparency, averaged over the visible, of 50%–71% formore » 200–250 nm thick films. In this range, synchrotron X-ray and electron diffraction reveal a nanocrystalline ZnS structure. Secondary crystalline Cu y S phases are not observed, and at higher Cu concentrations, x > 0.45, films are amorphous and poorly conducting. Furthermore, within the TCM regime, the conductivity is temperature independent, indicating degenerate hole conduction. A decrease in lattice parameter with Cu content suggests that the hole conduction is due to substitutional incorporation of Cu onto Zn sites. This hole-conducting phase is embedded in a less conducting amorphous Cu y S, which dominates at higher Cu concentrations. Finally, the combination of high hole conductivity and optical transparency for the peak conductivity Cu x Zn 1- x S films is among the best reported to date for a room temperature deposited p-type TCM.« less
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Shapiro, Allen M.; Ladderud, Jeffery; Yager, Richard M.
2015-01-01
A comparison of the hydraulic conductivity over increasingly larger volumes of crystalline rock was conducted in the Piedmont physiographic region near Bethesda, Maryland, USA. Fluid-injection tests were conducted on intervals of boreholes isolating closely spaced fractures. Single-hole tests were conducted by pumping in open boreholes for approximately 30 min, and an interference test was conducted by pumping a single borehole over 3 days while monitoring nearby boreholes. An estimate of the hydraulic conductivity of the rock over hundreds of meters was inferred from simulating groundwater inflow into a kilometer-long section of a Washington Metropolitan Area Transit Authority tunnel in the study area, and a groundwater modeling investigation over the Rock Creek watershed provided an estimate of the hydraulic conductivity over kilometers. The majority of groundwater flow is confined to relatively few fractures at a given location. Boreholes installed to depths of approximately 50 m have one or two highly transmissive fractures; the transmissivity of the remaining fractures ranges over five orders of magnitude. Estimates of hydraulic conductivity over increasingly larger rock volumes varied by less than half an order of magnitude. While many investigations point to increasing hydraulic conductivity as a function of the measurement scale, a comparison with selected investigations shows that the effective hydraulic conductivity estimated over larger volumes of rock can either increase, decrease, or remain stable as a function of the measurement scale. Caution needs to be exhibited in characterizing effective hydraulic properties in fractured rock for the purposes of groundwater management.
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A general population twin study of conduct problems and the auditory P300 waveform.
Bertoletti, Eleonora; Michelini, Giorgia; Moruzzi, Sara; Ferrer, Giuseppina; Ferini-Strambi, Luigi; Stazi, Maria Antonietta; Ogliari, Anna; Battaglia, Marco
2014-01-01
Reduced amplitude of the P300 event-related potential has been consistently associated with a variety of externalising problems, including conduct disorder. The few available genetically-informative studies of these relationships, however, were conducted among adolescents/adults (i.e., at an age when conduct disorder has typically already become manifest). Among 200 general population twins with a mean age of 9 years (range 6-14 years), we studied the relationship between the P300 waveform elicited by an auditory oddball task and the DSM-oriented conduct problems scale of the Child Behavior Checklist 6-18. Conduct problems scores were negatively and significantly correlated (r = -0.19, p = 0.01) with P300 amplitude; correlations between P300 amplitude and the other DSM-oriented Child Behavior Checklist scales were non-significant, except for oppositional defiant problems (p = 0.01). We found moderate heritability estimates for both P300 amplitude (0.58, CI:0.37;0.73) and conduct problems (0.52, CI:0.25;0.70). Bivariate twin analyses indicated that the covariation between these two phenotypes can be explained by additive genetic factors only, with a genetic correlation of -0.33. An association between reduced P300 amplitude and conduct problems can be substantiated already in childhood, at an age that precedes the most typical onset of conduct disorder. This relationship appears to be genetic in nature. Reduced P300 amplitude can represent a valuable marker for conduct problems, and can contribute to the early identification of children at high-risk for conduct disorder.
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Mays, Darren; Gilman, Stephen E; Rende, Richard; Luta, George; Tercyak, Kenneth P; Niaura, Raymond S
2014-06-01
Adolescents with conduct problems are more likely to smoke, and tobacco advertising exposure may exacerbate this risk. Males' excess risk for conduct problems and females' susceptibility to advertising suggest gender-specific pathways to smoking. We investigated the associations between gender, conduct problems, and lifetime smoking and adolescents' exposure to tobacco advertising, and we examined prospective relationships with smoking behaviors. Adolescents completed baseline (2001-2004; n = 541) and 5-year follow-up (2007-2009; n =320) interviews for a family study of smoking risk. Baseline interviews assessed conduct problems and tobacco advertising exposure; smoking behavior was assessed at both timepoints. Generalized linear models analyzed gender differences in the relationship between conduct problems, advertising exposure, and smoking behavior at baseline and longitudinally. At baseline, among males, conduct problems were associated with greater advertising exposure independent of demographics and lifetime smoking. Among females at baseline, conduct problems were associated with greater advertising exposure only among never-smokers after adjusting for demographics. In longitudinal analyses, baseline advertising exposure predicted subsequent smoking initiation (i.e., smoking their first cigarette between baseline and follow-up) for females but not for males. Baseline conduct problems predicted current (i.e., daily or weekly) smoking at follow-up for all adolescents in adjusted models. The findings of this study reinforce that conduct problems are a strong predictor of subsequent current smoking for all adolescents and reveal important differences between adolescent males and females in the relationship between conduct problems, tobacco advertising behavior, and smoking behavior. The findings suggest gender-specific preventive interventions targeting advertising exposure may be warranted.
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Detection of temperature distribution via recovering electrical conductivity in MREIT.
Oh, Tong In; Kim, Hyung Joong; Jeong, Woo Chul; Chauhan, Munish; Kwon, Oh In; Woo, Eung Je
2013-04-21
In radiofrequency (RF) ablation or hyperthermia, internal temperature measurements and tissue property imaging are important to control their outputs and assess the treatment effect. Recently, magnetic resonance electrical impedance tomography (MREIT), as a non-invasive imaging method of internal conductivity distribution using an MR scanner, has been developed. Its reconstruction algorithm uses measured magnetic flux density induced by injected currents. The MREIT technique has the potential to visualize electrical conductivity of tissue with high spatial resolution and measure relative conductivity variation according to the internal temperature change based on the fact that the electrical conductivity of biological tissues is sensitive to the internal temperature distribution. In this paper, we propose a method to provide a non-invasive alternative to monitor the internal temperature distribution by recovering the electrical conductivity distribution using the MREIT technique. To validate the proposed method, we design a phantom with saline solution and a thin transparency film in a form of a hollow cylinder with holes to create anomalies with different electrical and thermal conductivities controlled by morphological structure. We first prove the temperature maps with respect to spatial and time resolution by solving the thermal conductivity partial differential equation with the real phantom experimental environment. The measured magnetic flux density and the reconstructed conductivity distributions using the phantom experiments were compared to the simulated temperature distribution. The relative temperature variation of two testing objects with respect to the background saline was determined by the relative conductivity contrast ratio (rCCR,%). The relation between the temperature and conductivity measurements using MREIT was approximately linear with better accuracy than 0.22 °C.
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Hydrogenation of Penta-Graphene Leads to Unexpected Large Improvement in Thermal Conductivity.
Wu, Xufei; Varshney, Vikas; Lee, Jonghoon; Zhang, Teng; Wohlwend, Jennifer L; Roy, Ajit K; Luo, Tengfei
2016-06-08
Penta-graphene (PG) has been identified as a novel two-dimensional (2D) material with an intrinsic bandgap, which makes it especially promising for electronics applications. In this work, we use first-principles lattice dynamics and iterative solution of the phonon Boltzmann transport equation (BTE) to determine the thermal conductivity of PG and its more stable derivative, hydrogenated penta-graphene (HPG). As a comparison, we also studied the effect of hydrogenation on graphene thermal conductivity. In contrast to hydrogenation of graphene, which leads to a dramatic decrease in thermal conductivity, HPG shows a notable increase in thermal conductivity, which is much higher than that of PG. Considering the necessity of using the same thickness when comparing thermal conductivity values of different 2D materials, hydrogenation leads to a 63% reduction in thermal conductivity for graphene, while it results in a 76% increase for PG. The high thermal conductivity of HPG makes it more thermally conductive than most other semiconducting 2D materials, such as the transition metal chalcogenides. Our detailed analyses show that the primary reason for the counterintuitive hydrogenation-induced thermal conductivity enhancement is the weaker bond anharmonicity in HPG than PG. This leads to weaker phonon scattering after hydrogenation, despite the increase in the phonon scattering phase space. The high thermal conductivity of HPG may inspire intensive research around HPG and other derivatives of PG as potential materials for future nanoelectronic devices. The fundamental physics understood from this study may open up a new strategy to engineer thermal transport properties of other 2D materials by controlling bond anharmonicity via functionalization.
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A Model of Thermal Conductivity for Planetary Soils. 2; Theory for Cemented Soils
NASA Technical Reports Server (NTRS)
Piqueux, S.; Christensen, P. R.
2009-01-01
A numerical model of heat conduction through particulate media made of spherical grains cemented by various bonding agents is presented. The pore-filling gas conductivity, volume fraction, and thermal conductivity of the cementing phase are tunable parameters. Cement fractions <0.001-0.01% in volume have small effects on the soil bulk thermal conductivity. A significant conductivity increase (factor 3-8) is observed for bond fractions of 0.01 to 1% in volume. In the 1 to 15% bond fraction domain, the conductivity increases continuously but less intensely (25-100% conductivity increase compared to a 1% bond system). Beyond 15% of cements, the conductivity increases vigorously and the bulk conductivity rapidly approaches that of bedrock. The composition of the cements (i.e. conductivity) has little influence on the bulk thermal inertia of the soil, especially if the volume of bond <10%. These results indicate that temperature measurements are sufficient to detect cemented soils and quantify the amount of cementing phase, but the mineralogical nature of the bonds and the typical grain size are unlikely to be determined from orbit. On Mars, a widespread surface unit characterized by a medium albedo (0.19-0.26) and medium/high thermal inertia (200-600 J s(0.5)/sq m/K) has long been hypothesized to be associated with a duricrust. The fraction of cement required to fit the thermal data is less than approx.1-5% by volume. This small amount of material is consistent with orbital observations, confirming that soil cementation is an important factor controlling the thermal inertia of the Martian surface
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A model of thermal conductivity for planetary soils: 2. Theory for cemented soils
NASA Astrophysics Data System (ADS)
Piqueux, S.; Christensen, P. R.
2009-09-01
A numerical model of heat conduction through particulate media made of spherical grains cemented by various bonding agents is presented. The pore-filling gas conductivity, volume fraction, and thermal conductivity of the cementing phase are tunable parameters. Cement fractions <0.001-0.01% in volume have small effects on the soil bulk thermal conductivity. A significant conductivity increase (factor 3-8) is observed for bond fractions of 0.01 to 1% in volume. In the 1 to 15% bond fraction domain, the conductivity increases continuously but less intensely (25-100% conductivity increase compared to a 1% bond system). Beyond 15% of cements, the conductivity increases vigorously and the bulk conductivity rapidly approaches that of bedrock. The composition of the cements (i.e. conductivity) has little influence on the bulk thermal inertia of the soil, especially if the volume of bond <10%. These results indicate that temperature measurements are sufficient to detect cemented soils and quantify the amount of cementing phase, but the mineralogical nature of the bonds and the typical grain size are unlikely to be determined from orbit. On Mars, a widespread surface unit characterized by a medium albedo (0.19-0.26) and medium/high thermal inertia (200-600 J s-0.5 m-2 K-1) has long been hypothesized to be associated with a duricrust. The fraction of cement required to fit the thermal data is less than ˜1-5% by volume. This small amount of material is consistent with orbital observations, confirming that soil cementation is an important factor controlling the thermal inertia of the Martian surface.
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Evaluating a Computerized Aid for Conducting a Cognitive Task Analysis
2000-01-01
in conducting a cognitive task analysis . The conduct of a cognitive task analysis is costly and labor intensive. As a result, a few computerized aids...evaluation of a computerized aid, specifically CAT-HCI (Cognitive Analysis Tool - Human Computer Interface), for the conduct of a detailed cognitive task analysis . A
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39 CFR 447.21 - Prohibited conduct.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 39 Postal Service 1 2010-07-01 2010-07-01 false Prohibited conduct. 447.21 Section 447.21 Postal Service UNITED STATES POSTAL SERVICE PERSONNEL RULES OF CONDUCT FOR POSTAL EMPLOYEES Employee Conduct... for an examination of the Office of Personnel Management or Board of Examiners for the Foreign Service...
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Electrically conducting polymers for aerospace applications
NASA Technical Reports Server (NTRS)
Meador, Mary Ann B.; Gaier, James R.; Good, Brian S.; Sharp, G. R.; Meador, Michael A.
1991-01-01
Current research on electrically conducting polymers from 1974 to the present is reviewed focusing on the development of materials for aeronautic and space applications. Problems discussed include extended pi-systems, pyrolytic polymers, charge-transfer systems, conductive matrix resins for composite materials, and prospects for the use of conducting polymers in space photovoltaics.
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18 CFR 706.211 - General conduct prejudicial to the Government.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false General conduct prejudicial to the Government. 706.211 Section 706.211 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT Conduct and Responsibilities of Employees § 706.211...
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30 CFR 250.207 - What ancillary activities may I conduct?
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What ancillary activities may I conduct? 250... and Information Ancillary Activities § 250.207 What ancillary activities may I conduct? Before or... the Regional Supervisor may direct you to conduct ancillary activities. Ancillary activities include...
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5 CFR 919.630 - May the OPM impute conduct of one person to another?
Code of Federal Regulations, 2010 CFR
2010-01-01
...'s knowledge, approval or acquiescence. The organization's acceptance of the benefits derived from the conduct is evidence of knowledge, approval or acquiescence. (b) Conduct imputed from an... individual to whom the improper conduct is imputed either participated in, had knowledge of, or reason to...
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Code of Federal Regulations, 2011 CFR
2011-07-01
... employee ethical and other conduct standards and financial disclosure regulations. 0.735-10 Section 0.735-10 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS STANDARDS OF ETHICAL CONDUCT AND RELATED RESPONSIBILITIES Standards of Ethical Conduct and Related Responsibilities of...
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Code of Federal Regulations, 2011 CFR
2011-01-01
... disclosure and ethical conduct standards regulations. 400.101 Section 400.101 Banks and Banking EXPORT-IMPORT BANK OF THE UNITED STATES EMPLOYEE FINANCIAL DISCLOSURE AND ETHICAL CONDUCT STANDARDS REGULATIONS § 400.101 Cross-reference to employee financial disclosure and ethical conduct standards regulations...
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Code of Federal Regulations, 2011 CFR
2011-04-01
... 22 Foreign Relations 2 2011-04-01 2009-04-01 true Cross-reference to employee ethical conduct... INVESTMENT CORPORATION ADMINISTRATIVE PROVISIONS EMPLOYEE ETHICAL CONDUCT STANDARDS AND FINANCIAL DISCLOSURE REGULATIONS § 705.101 Cross-reference to employee ethical conduct standards and financial disclosure...
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Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 9 2011-10-01 2011-10-01 false Cross-referrence to employee ethical conduct standards... GENERAL AND ADMINISTRATIVE PROVISIONS EMPLOYEE ETHICAL CONDUCT STANDARDS AND FINANCIAL DISCLOSURE REGULATIONS § 508.101 Cross-referrence to employee ethical conduct standards and financial disclosure...
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7 CFR 1486.511 - What is the general policy regarding ethical conduct?
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 10 2011-01-01 2011-01-01 false What is the general policy regarding ethical conduct? 1486.511 Section 1486.511 Agriculture Regulations of the Department of Agriculture (Continued... ethical conduct? (a) The Recipient shall maintain written standards of conduct governing the performance...
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45 CFR 73.735-1002 - Ethical standards of conduct.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 45 Public Welfare 1 2011-10-01 2011-10-01 false Ethical standards of conduct. 73.735-1002 Section... Ethical standards of conduct. (a) Like other Federal employees, an individual serving in a consultant capacity must conduct himself or herself according to ethical behavior standards of the highest order. In...
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22 CFR 401.7 - Conduct of hearings.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Conduct of hearings. 401.7 Section 401.7 Foreign Relations INTERNATIONAL JOINT COMMISSION, UNITED STATES AND CANADA RULES OF PROCEDURE General § 401.7 Conduct of hearings. Hearings may be conducted, testimony received and arguments thereon heard by the...
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12 CFR 368.3 - Business conduct.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Business conduct. 368.3 Section 368.3 Banks and... SECURITIES SALES PRACTICES § 368.3 Business conduct. A bank that is a government securities broker or dealer... conduct of its business as a government securities broker or dealer. ...
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21 CFR 868.5150 - Anesthesia conduction needle.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Anesthesia conduction needle. 868.5150 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5150 Anesthesia conduction needle. (a) Identification. An anesthesia conduction needle is a device used to inject local anesthetics into a patient to...
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21 CFR 868.5150 - Anesthesia conduction needle.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Anesthesia conduction needle. 868.5150 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5150 Anesthesia conduction needle. (a) Identification. An anesthesia conduction needle is a device used to inject local anesthetics into a patient to...
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This SOP describes the method for conducting internal field audits and quality control procedures. Internal field audits will be conducted to ensure the collection of high quality data. Internal field audits will be conducted by Field Auditors (the Field QA Officer and the Field...
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Code of Federal Regulations, 2010 CFR
2010-04-01
... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Cross-reference to employee ethical conduct... INVESTMENT CORPORATION ADMINISTRATIVE PROVISIONS EMPLOYEE ETHICAL CONDUCT STANDARDS AND FINANCIAL DISCLOSURE REGULATIONS § 705.101 Cross-reference to employee ethical conduct standards and financial disclosure...
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Code of Federal Regulations, 2010 CFR
2010-07-01
... employee ethical and other conduct standards and financial disclosure regulations. 0.735-10 Section 0.735-10 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS STANDARDS OF ETHICAL CONDUCT AND RELATED RESPONSIBILITIES Standards of Ethical Conduct and Related Responsibilities of...
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Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 9 2010-10-01 2010-10-01 false Cross-referrence to employee ethical conduct standards... GENERAL AND ADMINISTRATIVE PROVISIONS EMPLOYEE ETHICAL CONDUCT STANDARDS AND FINANCIAL DISCLOSURE REGULATIONS § 508.101 Cross-referrence to employee ethical conduct standards and financial disclosure...
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7 CFR 1486.511 - What is the general policy regarding ethical conduct?
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 10 2010-01-01 2010-01-01 false What is the general policy regarding ethical conduct? 1486.511 Section 1486.511 Agriculture Regulations of the Department of Agriculture (Continued... ethical conduct? (a) The Recipient shall maintain written standards of conduct governing the performance...
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Code of Federal Regulations, 2010 CFR
2010-01-01
... disclosure and ethical conduct standards regulations. 400.101 Section 400.101 Banks and Banking EXPORT-IMPORT BANK OF THE UNITED STATES EMPLOYEE FINANCIAL DISCLOSURE AND ETHICAL CONDUCT STANDARDS REGULATIONS § 400.101 Cross-reference to employee financial disclosure and ethical conduct standards regulations...
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45 CFR 73.735-1002 - Ethical standards of conduct.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 45 Public Welfare 1 2010-10-01 2010-10-01 false Ethical standards of conduct. 73.735-1002 Section... Ethical standards of conduct. (a) Like other Federal employees, an individual serving in a consultant capacity must conduct himself or herself according to ethical behavior standards of the highest order. In...
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25 CFR 1000.355 - How are trust evaluations conducted?
Code of Federal Regulations, 2010 CFR
2010-04-01
... 25 Indians 2 2010-04-01 2010-04-01 false How are trust evaluations conducted? 1000.355 Section... EDUCATION ACT Trust Evaluation Review Annual Trust Evaluations § 1000.355 How are trust evaluations conducted? (a) Each year the Secretary's designated representative(s) will conduct trust evaluations for...
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12 CFR 368.3 - Business conduct.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 12 Banks and Banking 5 2013-01-01 2013-01-01 false Business conduct. 368.3 Section 368.3 Banks and... SECURITIES SALES PRACTICES § 368.3 Business conduct. A bank that is a government securities broker or dealer... conduct of its business as a government securities broker or dealer. ...
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12 CFR 368.3 - Business conduct.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 12 Banks and Banking 4 2011-01-01 2011-01-01 false Business conduct. 368.3 Section 368.3 Banks and... SECURITIES SALES PRACTICES § 368.3 Business conduct. A bank that is a government securities broker or dealer... conduct of its business as a government securities broker or dealer. ...
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12 CFR 368.3 - Business conduct.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 12 Banks and Banking 5 2012-01-01 2012-01-01 false Business conduct. 368.3 Section 368.3 Banks and... SECURITIES SALES PRACTICES § 368.3 Business conduct. A bank that is a government securities broker or dealer... conduct of its business as a government securities broker or dealer. ...
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12 CFR 368.3 - Business conduct.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 12 Banks and Banking 5 2014-01-01 2014-01-01 false Business conduct. 368.3 Section 368.3 Banks and... SECURITIES SALES PRACTICES § 368.3 Business conduct. A bank that is a government securities broker or dealer... conduct of its business as a government securities broker or dealer. ...
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48 CFR 32.202-3 - Conducting market research about financing terms.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Conducting market research... 32.202-3 Conducting market research about financing terms. Contract financing may be a subject included in the market research conducted in accordance with part 10. If market research for contract...
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48 CFR 32.202-3 - Conducting market research about financing terms.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Conducting market research... 32.202-3 Conducting market research about financing terms. Contract financing may be a subject included in the market research conducted in accordance with part 10. If market research for contract...
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18 CFR 706.211 - General conduct prejudicial to the Government.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false General conduct prejudicial to the Government. 706.211 Section 706.211 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT Conduct and Responsibilities of Employees § 706.211...
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18 CFR 706.211 - General conduct prejudicial to the Government.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false General conduct prejudicial to the Government. 706.211 Section 706.211 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT Conduct and Responsibilities of Employees § 706.211...
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18 CFR 706.211 - General conduct prejudicial to the Government.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false General conduct prejudicial to the Government. 706.211 Section 706.211 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT Conduct and Responsibilities of Employees § 706.211...
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18 CFR 706.211 - General conduct prejudicial to the Government.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true General conduct prejudicial to the Government. 706.211 Section 706.211 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT Conduct and Responsibilities of Employees § 706.211...
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Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 9 2014-10-01 2014-10-01 false Cross-referrence to employee ethical conduct standards... GENERAL AND ADMINISTRATIVE PROVISIONS EMPLOYEE ETHICAL CONDUCT STANDARDS AND FINANCIAL DISCLOSURE REGULATIONS § 508.101 Cross-referrence to employee ethical conduct standards and financial disclosure...
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Code of Federal Regulations, 2014 CFR
2014-04-01
... 22 Foreign Relations 2 2014-04-01 2014-04-01 false Cross-reference to employee ethical conduct... INVESTMENT CORPORATION ADMINISTRATIVE PROVISIONS EMPLOYEE ETHICAL CONDUCT STANDARDS AND FINANCIAL DISCLOSURE REGULATIONS § 705.101 Cross-reference to employee ethical conduct standards and financial disclosure...
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Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 9 2012-10-01 2012-10-01 false Cross-referrence to employee ethical conduct standards... GENERAL AND ADMINISTRATIVE PROVISIONS EMPLOYEE ETHICAL CONDUCT STANDARDS AND FINANCIAL DISCLOSURE REGULATIONS § 508.101 Cross-referrence to employee ethical conduct standards and financial disclosure...
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Code of Federal Regulations, 2013 CFR
2013-01-01
... disclosure and ethical conduct standards regulations. 400.101 Section 400.101 Banks and Banking EXPORT-IMPORT BANK OF THE UNITED STATES EMPLOYEE FINANCIAL DISCLOSURE AND ETHICAL CONDUCT STANDARDS REGULATIONS § 400.101 Cross-reference to employee financial disclosure and ethical conduct standards regulations...
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Code of Federal Regulations, 2012 CFR
2012-01-01
... disclosure and ethical conduct standards regulations. 400.101 Section 400.101 Banks and Banking EXPORT-IMPORT BANK OF THE UNITED STATES EMPLOYEE FINANCIAL DISCLOSURE AND ETHICAL CONDUCT STANDARDS REGULATIONS § 400.101 Cross-reference to employee financial disclosure and ethical conduct standards regulations...
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Code of Federal Regulations, 2013 CFR
2013-04-01
... 22 Foreign Relations 2 2013-04-01 2009-04-01 true Cross-reference to employee ethical conduct... INVESTMENT CORPORATION ADMINISTRATIVE PROVISIONS EMPLOYEE ETHICAL CONDUCT STANDARDS AND FINANCIAL DISCLOSURE REGULATIONS § 705.101 Cross-reference to employee ethical conduct standards and financial disclosure...
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Code of Federal Regulations, 2012 CFR
2012-07-01
... employee ethical and other conduct standards and financial disclosure regulations. 0.735-10 Section 0.735-10 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS STANDARDS OF ETHICAL CONDUCT AND RELATED RESPONSIBILITIES Standards of Ethical Conduct and Related Responsibilities of...
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Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 9 2013-10-01 2013-10-01 false Cross-referrence to employee ethical conduct standards... GENERAL AND ADMINISTRATIVE PROVISIONS EMPLOYEE ETHICAL CONDUCT STANDARDS AND FINANCIAL DISCLOSURE REGULATIONS § 508.101 Cross-referrence to employee ethical conduct standards and financial disclosure...
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Code of Federal Regulations, 2012 CFR
2012-04-01
... 22 Foreign Relations 2 2012-04-01 2009-04-01 true Cross-reference to employee ethical conduct... INVESTMENT CORPORATION ADMINISTRATIVE PROVISIONS EMPLOYEE ETHICAL CONDUCT STANDARDS AND FINANCIAL DISCLOSURE REGULATIONS § 705.101 Cross-reference to employee ethical conduct standards and financial disclosure...
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Code of Federal Regulations, 2014 CFR
2014-01-01
... disclosure and ethical conduct standards regulations. 400.101 Section 400.101 Banks and Banking EXPORT-IMPORT BANK OF THE UNITED STATES EMPLOYEE FINANCIAL DISCLOSURE AND ETHICAL CONDUCT STANDARDS REGULATIONS § 400.101 Cross-reference to employee financial disclosure and ethical conduct standards regulations...
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21 CFR 868.5150 - Anesthesia conduction needle.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Anesthesia conduction needle. 868.5150 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5150 Anesthesia conduction needle. (a) Identification. An anesthesia conduction needle is a device used to inject local anesthetics into a patient to...
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Isochoric thermal conductivity of solid n-alkanes: Hexane C6H14
NASA Astrophysics Data System (ADS)
Konstantinov, V. A.; Revyakin, V. P.; Sagan, V. V.
2011-05-01
The isochoric thermal conductivity of solid n-hexane C6H14 is studied using three samples with different densities for temperatures ranging from 100 K to the onset of melting. In all cases, the isochoric thermal conductivity varies more weakly than Λ∝1/T. The present results are compared with the thermal conductivities of other representatives of the n-alkanes. The contributions of low-frequency phonons and "diffuse modes" to the thermal conductivity are calculated.
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Experimental Investigation of Electrical Conductivity and Permittivity of SC-TiO 2 -EG Nanofluids.
Fal, Jacek; Barylyak, Adriana; Besaha, Khrystyna; Bobitski, Yaroslav V; Cholewa, Marian; Zawlik, Izabela; Szmuc, Kamil; Cebulski, Józef; Żyła, Gaweł
2016-12-01
The paper presents experimental studies of dielectric properties of nanofluids based on ethylene glycol and SC-TiO2 nanoparticles with average size of 15-40 nm with various mass concentrations. The dielectric permittivity both real part and imaginary part as a function of temperature and frequency were measured. Also, dependence ac conductivity on frequency, temperature, and mass concentration were investigated. Based on the curves of ac conductivity, dc conductivity was calculated, and 400 % enhancement in dc conductivity was exposed.
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Experimental Investigation of Electrical Conductivity and Permittivity of SC-TiO 2 -EG Nanofluids
NASA Astrophysics Data System (ADS)
Fal, Jacek; Barylyak, Adriana; Besaha, Khrystyna; Bobitski, Yaroslav V.; Cholewa, Marian; Zawlik, Izabela; Szmuc, Kamil; Cebulski, Józef; żyła, Gaweł
2016-08-01
The paper presents experimental studies of dielectric properties of nanofluids based on ethylene glycol and SC-TiO2 nanoparticles with average size of 15-40 nm with various mass concentrations. The dielectric permittivity both real part and imaginary part as a function of temperature and frequency were measured. Also, dependence ac conductivity on frequency, temperature, and mass concentration were investigated. Based on the curves of ac conductivity, dc conductivity was calculated, and 400 % enhancement in dc conductivity was exposed.
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Composite mixed oxide ionic and electronic conductors for hydrogen separation
Gopalan, Srikanth [Westborough, MA; Pal, Uday B [Dover, MA; Karthikeyan, Annamalai [Quincy, MA; Hengdong, Cui [Allston, MA
2009-09-15
A mixed ionic and electronic conducting membrane includes a two-phase solid state ceramic composite, wherein the first phase comprises an oxygen ion conductor and the second phase comprises an n-type electronically conductive oxide, wherein the electronically conductive oxide is stable at an oxygen partial pressure as low as 10.sup.-20 atm and has an electronic conductivity of at least 1 S/cm. A hydrogen separation system and related methods using the mixed ionic and electronic conducting membrane are described.
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Method of forming an electrically conductive cellulose composite
Evans, Barbara R [Oak Ridge, TN; O'Neill, Hugh M [Knoxville, TN; Woodward, Jonathan [Ashtead, GB
2011-11-22
An electrically conductive cellulose composite includes a cellulose matrix and an electrically conductive carbonaceous material incorporated into the cellulose matrix. The electrical conductivity of the cellulose composite is at least 10 .mu.S/cm at 25.degree. C. The composite can be made by incorporating the electrically conductive carbonaceous material into a culture medium with a cellulose-producing organism, such as Gluconoacetobacter hansenii. The composites can be used to form electrodes, such as for use in membrane electrode assemblies for fuel cells.
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Electron Induced Conductivity of Al2O3 as Pertaining to Thermionic Integrated Circuits.
1985-12-01
No.6, pp. 4450-4456, December 1983. 18. Pomerantz, M. A., Shatas, R. A. and Marshall, 3. F., "Electrical Conductivity Induced in MgO Crystals by 1.3...Experiments were conducted to measure the electron induced conductivity CEIC) of single crystal sapphire (A120 ) and poly-crystalline alumina (A1203 ). The...induced conductivity (EIC) of single crystal sapphire (A li2O-) and poly-crystalline alumina (Alzz2O. The EIC is generated when the samples are bombarded