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Sample records for additional experiments conducted

  1. Conducting Miller-Urey Experiments

    NASA Technical Reports Server (NTRS)

    Parker, Eric Thomas; Cleaves, Henderson James; Burton, Aaron S.; Glavin, Daniel P.; Dworkin, Jason; Zhou, Manshui; Bada, Jeffrey L.; Fernandez, Facundo M.

    2014-01-01

    In 1953, Stanley Miller reported the production of biomolecules from simple gaseous starting materials, using apparatus constructed to simulate the primordial Earth's atmosphere-ocean system. Miller introduced 200 ml of water, 100 mmHg of H2, 200mmHg of CH4, and 200mmHg of NH3 into the apparatus, then subjected this mixture, under reflux, to an electric discharge for a week, while the water was simultaneously heated. The purpose of this manuscript is to provide the reader with a general experimental protocol that can be used to conduct a Miller-Urey type spark discharge experiment, using a simplified 3 L reaction flask. Since the experiment involves exposing inflammable gases to a high voltage discharge, it is worth highlighting important steps that reduce the risk of explosion. The general procedures described in this work can be extrapolated to design and conduct a wide variety of electric discharge experiments simulating primitive planetary environments.

  2. Conducting Miller-Urey Experiments

    PubMed Central

    Parker, Eric T.; Cleaves, James H.; Burton, Aaron S.; Glavin, Daniel P.; Dworkin, Jason P.; Zhou, Manshui; Bada, Jeffrey L.; Fernández, Facundo M.

    2014-01-01

    In 1953, Stanley Miller reported the production of biomolecules from simple gaseous starting materials, using an apparatus constructed to simulate the primordial Earth's atmosphere-ocean system. Miller introduced 200 ml of water, 100 mmHg of H2, 200 mmHg of CH4, and 200 mmHg of NH3 into the apparatus, then subjected this mixture, under reflux, to an electric discharge for a week, while the water was simultaneously heated. The purpose of this manuscript is to provide the reader with a general experimental protocol that can be used to conduct a Miller-Urey type spark discharge experiment, using a simplified 3 L reaction flask. Since the experiment involves exposing inflammable gases to a high voltage electric discharge, it is worth highlighting important steps that reduce the risk of explosion. The general procedures described in this work can be extrapolated to design and conduct a wide variety of electric discharge experiments simulating primitive planetary environments. PMID:24473135

  3. Conducting miller-urey experiments.

    PubMed

    Parker, Eric T; Cleaves, James H; Burton, Aaron S; Glavin, Daniel P; Dworkin, Jason P; Zhou, Manshui; Bada, Jeffrey L; Fernández, Facundo M

    2014-01-01

    In 1953, Stanley Miller reported the production of biomolecules from simple gaseous starting materials, using an apparatus constructed to simulate the primordial Earth's atmosphere-ocean system. Miller introduced 200 ml of water, 100 mmHg of H2, 200 mmHg of CH4, and 200 mmHg of NH3 into the apparatus, then subjected this mixture, under reflux, to an electric discharge for a week, while the water was simultaneously heated. The purpose of this manuscript is to provide the reader with a general experimental protocol that can be used to conduct a Miller-Urey type spark discharge experiment, using a simplified 3 L reaction flask. Since the experiment involves exposing inflammable gases to a high voltage electric discharge, it is worth highlighting important steps that reduce the risk of explosion. The general procedures described in this work can be extrapolated to design and conduct a wide variety of electric discharge experiments simulating primitive planetary environments. PMID:24473135

  4. Conducting plant experiments in space.

    PubMed

    Kiss, John Z

    2015-01-01

    The growth and development of plants during spaceflight have important implications for both basic and applied research supported by NASA and other international space agencies. While there have been many reviews of plant space biology, the present chapter attempts to fill a gap in the literature on the actual process and methods of performing plant research in the spaceflight environment. The author has been a principal investigator on six spaceflight projects and has another two space experiments in development. These experiences include using the US Space Shuttle, the former Russian space station Mir, and the International Space Station, utilizing the Space Shuttle and Space X as launch vehicles. While there are several ways to obtain a spaceflight opportunity, this review focuses on using the NASA peer-reviewed sciences approach to get an experiment manifested for flight. Three narratives for the implementation of plant space biology experiments are considered from rapid turnaround of a few months to a project with new hardware development that lasted 6 years. The many challenges of spaceflight research include logistical and resource constraints such as crew time, power, cold stowage, and data downlinks, among others. Additional issues considered are working at NASA centers, hardware development, safety concerns, and the engineering versus science culture in space agencies. The difficulties of publishing the results from spaceflight research based on such factors as the lack of controls, limited sample size, and the indirect effects of the spaceflight environment also are summarized. Finally, lessons learned from these spaceflight experiences are discussed in the context of improvements for future space-based research projects with plants. PMID:25981781

  5. French and English Together: An "Additive" Experience

    ERIC Educational Resources Information Center

    Wiltshire, Jessica; Harbon, Lesley

    2010-01-01

    This paper examines the nature of the "additive" experience of a bilingual French-English curriculum at Killarney Heights Public School in New South Wales. Predictably, the well-supported "additive" nature of the languages program model elicited positive reactions regarding educational success. The paper also explores issues for administration,…

  6. Fire extinct experiments with water mist by adding additives

    NASA Astrophysics Data System (ADS)

    Yang, Lijun; Zhao, Jianbo

    2011-12-01

    The effects of fire extinguishment with water mist by adding different additives were studied. Tens of chemical substances (including alkali metal salt, dilution agent and surface active agent) were selected as additives due to their different extinct mechanisms. At first the performance of fire extinguishment with single additive was studied, then the effects of the same kinds of chemical substances under the same mass fraction were compared to study their influences on the fire extinguishment factors, including extinct time, fire temperature and oxygen concentration from which the fire extinct mechanism with additives could be concluded. Based on this the experiments were conducted to study the cooperate effect of the complexity of different additives. It indicated the relations between different firefighting mechanisms and different additives were competitive. From a large number of experiments the extinct mechanism with water mist by adding additives was concluded and an optimal compounding additive was selected.

  7. Segmentation of conducting domains in PEDOT:PSS films induced by an additive for conductivity enhancement

    NASA Astrophysics Data System (ADS)

    Unuma, Takeya; Yoshikawa, Muneki; Nakamura, Arao; Kishida, Hideo

    2016-05-01

    We investigate the relationship between the morphology and in-plane conductivity of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films made from aqueous dispersions with/without ethylene glycol additive. Nanometer-scale current images of the films obtained using a conductive atomic-force microscope reveal that PEDOT-rich highly conducting domains are segmented into smaller ones — with the total area of these domains being nearly constant — for larger percentages of ethylene glycol leading to higher in-plane conductivities. The in-plane transport mechanism is found to have a strong dependence on the effective thickness of insulating barriers formed by excess PSS between neighboring highly conducting domains.

  8. Data on conducting the SAMEX-76 experiment

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The compilation of data on conducting the SAMEX-76 experiment is reported. This report includes many tables and graphs of the aircraft's flights and its measurements. Also given is the operation time of this equipment and the many observations that have been made by the Scientific Research Ship Akademik Korolev.

  9. Experiments On Transparent Conductive Films For Spacecraft

    NASA Technical Reports Server (NTRS)

    Perez-Davis, Marla E.; Rutledge, Sharon K.; De Groh, Kim K.; Hung, Ching-Cheh; Malave-Sanabria, Tania; Hambourger, Paul; Roig, David

    1995-01-01

    Report describes experiments on thin, transparent, electrically conductive films made, variously, of indium tin oxide covered by magnesium fluoride (ITO/MgF2), aluminum-doped zinc oxide (AZO), or pure zinc oxide (ZnO). Films are candidates for application to such spacecraft components, including various optoelectronic devices and window surfaces that must be protected against buildup of static electric charge. On Earth, such films useful on heat mirrors, optoelectronic devices, gas sensors, and automotive and aircraft windows.

  10. Developing a High Thermal Conductivity Fuel with Silicon Carbide Additives

    SciTech Connect

    baney, Ronald; Tulenko, James

    2012-11-20

    The objective of this research is to increase the thermal conductivity of uranium oxide (UO{sub 2}) without significantly impacting its neutronic properties. The concept is to incorporate another high thermal conductivity material, silicon carbide (SiC), in the form of whiskers or from nanoparticles of SiC and a SiC polymeric precursor into UO{sub 2}. This is expected to form a percolation pathway lattice for conductive heat transfer out of the fuel pellet. The thermal conductivity of SiC would control the overall fuel pellet thermal conductivity. The challenge is to show the effectiveness of a low temperature sintering process, because of a UO{sub 2}-SiC reaction at 1,377°C, a temperature far below the normal sintering temperature. Researchers will study three strategies to overcome the processing difficulties associated with pore clogging and the chemical reaction of SiC and UO{sub 2} at temperatures above 1,300°C:

  11. Conductivity and structure of bilinear organic addition compounds

    PubMed Central

    Phillips, J. C.

    1976-01-01

    The relationship between crystal structures and metallic conductivities of linear organic materials such as tetrathiafulvalene-tetracyanoquinodimethane is explained in terms of strong lateral elastic interactions between chains. A microdomain model is presented in which at high temperatures there are, in general, two coexisting phases on each stacked molecular chain. The ordering of (in general, four) phases on two interacting chains leads to a variety of phase transitions at low temperatures. By examining temperature-dependent electrical conductivities and magnetic susceptibilities one can establish the character of each such transition. PMID:16592359

  12. Cell biology experiments conducted in space

    NASA Technical Reports Server (NTRS)

    Taylor, G. R.

    1977-01-01

    A review of cell biology experiments conducted during the first two decades of space flight is provided. References are tabulated for work done with six types of living test system: isolated viruses, bacteriophage-host, bacteria, yeasts and filamentous fungi, protozoans, and small groups of cells (such as hamster cell tissue and fertilized frog eggs). The general results of studies involving the survival of cells in space, the effect of space flight on growing cultures, the biological effects of multicharged high-energy particles, and the effects of space flight on the genetic apparatus of microorganisms are summarized. It is concluded that cell systems remain sufficiently stable during space flight to permit experimentation with models requiring a fixed cell line during the space shuttle era.

  13. Tin nanoparticles as an effective conductive additive in silicon anodes.

    PubMed

    Zhong, L; Beaudette, C; Guo, J; Bozhilov, K; Mangolini, L

    2016-01-01

    We have found that the addition of tin nanoparticles to a silicon-based anode provides dramatic improvements in performance in terms of both charge capacity and cycling stability. Using a simple procedure and off-the-shelf additives and precursors, we developed a structure in which the tin nanoparticles are segregated at the interface between the silicon-containing active layer and the solid electrolyte interface. Even a minor addition of tin, as small as ∼2% by weight, results in a significant decrease in the anode resistance, as confirmed by electrochemical impedance spectroscopy. This leads to a decrease in charge transfer resistance, which prevents the formation of electrically inactive "dead spots" in the anode structure and enables the effective participation of silicon in the lithiation reaction. PMID:27484849

  14. Tin nanoparticles as an effective conductive additive in silicon anodes

    PubMed Central

    Zhong, L.; Beaudette, C.; Guo, J.; Bozhilov, K.; Mangolini, L.

    2016-01-01

    We have found that the addition of tin nanoparticles to a silicon-based anode provides dramatic improvements in performance in terms of both charge capacity and cycling stability. Using a simple procedure and off-the-shelf additives and precursors, we developed a structure in which the tin nanoparticles are segregated at the interface between the silicon-containing active layer and the solid electrolyte interface. Even a minor addition of tin, as small as ∼2% by weight, results in a significant decrease in the anode resistance, as confirmed by electrochemical impedance spectroscopy. This leads to a decrease in charge transfer resistance, which prevents the formation of electrically inactive “dead spots” in the anode structure and enables the effective participation of silicon in the lithiation reaction. PMID:27484849

  15. Tin nanoparticles as an effective conductive additive in silicon anodes

    NASA Astrophysics Data System (ADS)

    Zhong, L.; Beaudette, C.; Guo, J.; Bozhilov, K.; Mangolini, L.

    2016-08-01

    We have found that the addition of tin nanoparticles to a silicon-based anode provides dramatic improvements in performance in terms of both charge capacity and cycling stability. Using a simple procedure and off-the-shelf additives and precursors, we developed a structure in which the tin nanoparticles are segregated at the interface between the silicon-containing active layer and the solid electrolyte interface. Even a minor addition of tin, as small as ∼2% by weight, results in a significant decrease in the anode resistance, as confirmed by electrochemical impedance spectroscopy. This leads to a decrease in charge transfer resistance, which prevents the formation of electrically inactive “dead spots” in the anode structure and enables the effective participation of silicon in the lithiation reaction.

  16. Conductance of Ion Channels - Theory vs. Experiment

    NASA Technical Reports Server (NTRS)

    Pohorille, Andrew; Wilson, Michael; Mijajlovic, Milan

    2013-01-01

    . In addition, once the free energy profile becomes available the full current-voltage dependence can be readily obtained. For both channels we carried out calculations using both approaches. We also tested the main assumptions underlying the diffusive model, such as uncorrelated nature of individual crossing events and Fickian diffusion. The accuracy and consistency of different methods will be discussed. Finally we will discuss how comparisons between calculated and measured ionic conductance and selectivity of transport can be used for determining structural models of the channels.

  17. A Guide for Conducting Outdoor Field Experiences.

    ERIC Educational Resources Information Center

    Matthews, Bruce; And Others

    Since research indicates teachers generally lack confidence in their ability to conduct lessons in the outdoors and feel inadequate regarding knowledge of the natural world, this guide has been developed to build teacher confidence in utilizing the outdoors. Designed to be used in conjunction with a practicum workshop, this guide presents…

  18. Payload specialists Patrick Baudry conducts equilibrium experiments

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Payload specialists Patrick Baudry participates in an experiment involving equilibrium and vertigo. He is anchored to the orbiter floor by foot restraints and is wearing a device over his eyes to measure angular head movement and up and down eye movement.

  19. Wheel Abrasion Experiment Conducted on Mars

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.

    1998-01-01

    Sojourner rover showing Lewis' wheel abrasion experiment. The Mars Pathfinder spacecraft soft-landed on Mars on July 4, 1997. Among the many experiments on its small Sojourner rover are three technology experiments from the NASA Lewis Research Center, including the Wheel Abrasion Experiment (WAE). The WAE was designed, built, delivered, and operated on Mars by a team of engineers and scientists from Lewis' Photovoltaics and Space Environments Branch. This experiment collected data to assess wheel surface wear on the Sojourner. It used a specially designed rover wheel, with thin films (200 to 1000 angstroms) of aluminum, nickel, and platinum deposited on black, anodized aluminum strips attached to the rover's right center wheel. As the wheel spun in the Martian soil, a photovoltaic sensor monitored changes in film reflectivity. These changes indicated abrasion of the metal films by Martian surface material. Rolling wear data were accumulated by the WAE. Also, at frequent intervals, all the rover wheels, except the WAE test wheel, were locked to hold the rover stationary while the test wheel alone was spun and dug into the Martian regolith. These tests created wear conditions more severe than simple rolling. The WAE will contribute substantially to our knowledge of Martian surface characteristics. Marked abrasion would indicate a surface composed of hard, possibly sharply edged grains, whereas lack of abrasion would suggest a somewhat softer surface. WAE results will be correlated with ground simulations to determine which terrestrial materials behave most like those on Mars. This knowledge will enable a deeper understanding of erosion processes on Mars and the role they play in Martian surface evolution. Preliminary results show that electrostatic charging of the rover wheels sometimes caused dust to accumulate on the WAE wheel, making interpretation of the reflectance data problematic. If electrostatic charging is the mechanism for dust attraction, this indicates

  20. Polymer Photooxidation: An Experiment to Demonstrate the Effect of Additives.

    ERIC Educational Resources Information Center

    Allen, Norman S.; McKellar, John F.

    1979-01-01

    This undergraduate experiment shows that the inclusion of an appropriate additive can have a very marked effect on the physical properties of a polymer. The polymer used is polypropylene and the additives are 2-hydroxy-4-octyloxy-benzophenone and benzophenone. (BB)

  1. Effect of conductive additives in LiFePO4 cathode for lithium-ion batteries

    SciTech Connect

    Shim, J.; Guerfi, A.; Zaghib, K.; Striebel, K.A.

    2003-11-25

    The electrochemical properties of LiFePO4 cathodes with different carbon contents were studied to find out the role of carbon as conductive additive. LiFePO4 cathodes containing from 0 percent to 12 percent of conductive additive (carbon black or mixture of carbon black and graphite) were cycled at different C rates. The capacity of LiFePO4 cathode increased, as conductive additive content increased. Carbon increased the utilization of active material and the electrical conductivity of electrode, but decreased volumetric capacity of electrode.

  2. Analysis of Microgravity Experiments Conducted on the Apollo Spacecraft

    NASA Technical Reports Server (NTRS)

    Sharpe, R. J.; Wright, M. D.

    2009-01-01

    This Technical Memorandum (TM) discusses the microgravity experiments carried out during the later missions of the Apollo program. Microgravity experiments took place during the Apollo 14, 16, and 17 missions and consisted of four experiments in various materials processing concentrations with two of the four experiments taking place over the course of two missions. Experiments consist of composite casting, electrophoresis, heat flow and convection, and liquid transfer. This TM discusses the background, the workup, execution, and results of each experiment. In addition, the historical significance of each experiment to future applications/NASA programs is discussed.

  3. Results from the cascaded variable conductance heatpipe experiment on LDEF

    NASA Technical Reports Server (NTRS)

    Grote, Michael G.

    1991-01-01

    A Variable Conductance Heat Pipe Experiment (CVCHPE) was successfully flown onboard the LDEF and demonstrated temperature control better than +/- 0.3 C during 50 days of on-orbit data collection in a widely varying external environment. The experiment used two series connected, dry reservoir variable conductance heat pipes which require no electrical power for operation. The heat pipes used a central artery design with ammonia working fluid and nitrogen control gas.

  4. 30 CFR 250.1925 - May BOEMRE direct me to conduct additional audits?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... SHELF Safety and Environmental Management Systems (SEMS) § 250.1925 May BOEMRE direct me to conduct... 30 Mineral Resources 2 2011-07-01 2011-07-01 false May BOEMRE direct me to conduct additional audits? 250.1925 Section 250.1925 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION,...

  5. An Experiment in Heat Conduction Using Hollow Cylinders

    ERIC Educational Resources Information Center

    Ortuno, M.; Marquez, A.; Gallego, S.; Neipp, C.; Belendez, A.

    2011-01-01

    An experimental apparatus was designed and built to allow students to carry out heat conduction experiments in hollow cylinders made of different materials, as well as to determine the thermal conductivity of these materials. The evolution of the temperature difference between the inner and outer walls of the cylinder as a function of time is…

  6. Carbon Nanotube/Conductive Additive/Space Durable Polymer Nanocomposite Films for Electrostatic Charge Dissipation

    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.

  7. Estimation of stream nutrient uptake from nutrient addition experiments

    SciTech Connect

    Payn, Robert

    2005-09-01

    Nutrient uptake in streams is often quantified by determining nutrient uptake length. However, current methods for measuring nutrient uptake length are often impractical, expensive, or demonstrably incorrect. We have developed a new method to estimate ambient nutrient uptake lengths using field experiments involving several levels of nutrient addition. Data analysis involves plotting nutrient addition uptake lengths versus added concentration and extrapolating to the negative ambient concentration. This method is relatively easy, inexpensive, and based on sound theoretical development. It is more accurate than the commonly used method involving a single nutrient addition. The utility of the method is supported by field studies directly comparing our new method with isotopic tracer methods for determining uptake lengths of phosphorus, ammonium, and nitrate. Our method also provides parameters for comparing potential nutrient limitation among streams.

  8. Development of high capacity, high rate lithium ion batteries utilizing metal fiber conductive additives

    NASA Astrophysics Data System (ADS)

    Ahn, Soonho; Kim, Youngduk; Kim, Kyung Joon; Kim, Tae Hyung; Lee, Hyungkeun; Kim, Myung H.

    As lithium ion cells dominate the battery market, the performance improvement is an utmost concern among developers and researchers. Conductive additives are routinely employed to enhance electrode conductivity and capacity. Carbon particulates—graphite or carbon black powders—are conventional and popular choices as conductive fillers. However, percolation requirements of particles demand significant volumetric content of impalpable, and thereby high area conductive fillers. As might be expected, the electrode active surface area escalates unnecessarily, resulting in overall increase in reaction with electrolytes and organic solvents. The increased reactions usually manifest as an irreversible loss of anode capacity, gradual oxidation and consumption of electrolyte on the cathode—which causes capacity decline during cycling—and an increased threat to battery safety by gas evolution and exothermic solvent oxidation. In this work we have utilized high aspect ratio, flexible, micronic metal fibers as low active area and high conductivity additives. The metal fibers appear well dispersed within the electrode and to satisfy percolation requirements very efficiently at very low volumetric content compared to conventional carbon-based conductive additives. Results from 18650-type cells indicate significant enhancements in electrode capacity and high rate capability while the irreversible capacity loss is negligible.

  9. Effects of an additional dimension in the Young experiment

    SciTech Connect

    Barros, Allan Kardec

    2015-09-15

    The results of the Young experiment can be analyzed either by classical or Quantum Physics. The later one though leads to a more complete interpretation, based on two different patterns that appear when one works either with single or double slits. Here we show that the two patterns can be derived from a single principle, in the context of General Relativity, if one assumes an additional spatial dimension to the four known today. The found equations yield the same results as those in Quantum Mechanics.

  10. Inventory Control. Easily Made Electronic Device for Conductivity Experiments.

    ERIC Educational Resources Information Center

    Gadek, Frank J.

    1987-01-01

    Describes how to construct an electronic device to be used in conductivity experiments using a 35 millimeter film canister, nine volt battery replacement snaps, a 200-300 ohm resistor, and a light-emitting diode. Provides a diagram and photographs of the device. (TW)

  11. Comparison of carbon onions and carbon blacks as conductive additives for carbon supercapacitors in organic electrolytes

    NASA Astrophysics Data System (ADS)

    Jäckel, N.; Weingarth, D.; Zeiger, M.; Aslan, M.; Grobelsek, I.; Presser, V.

    2014-12-01

    This study investigates carbon onions (∼400 m2 g-1) as a conductive additive for supercapacitor electrodes of activated carbon and compares their performance with carbon black with high or low internal surface area. We provide a study of the electrical conductivity and electrochemical behavior between 2.5 and 20 mass% addition of each of these three additives to activated carbon. Structural characterization shows that the density of the resulting film electrodes depends on the degree of agglomeration and the amount of additive. Addition of low surface area carbon black (∼80 m2 g-1) enhances the power handling of carbon electrodes but significantly lowers the specific capacitance even when adding small amounts of carbon black. A much lower decrease in specific capacitance is observed for carbon onions and the best values are seen for carbon black with a high surface area (∼1390 m2 g-1). The overall performance benefits from the addition of any of the studied additives only at either high scan rates and/or electrolytes with high ion mobility. Normalization to the volume shows a severe decrease in volumetric capacitance and only at high current densities nearing 10 A g-1 we can see an improvement of the electrode capacitance.

  12. Lessons learned from experiments conducted on radar data management systems

    NASA Astrophysics Data System (ADS)

    Pierce, Mark W.

    1994-06-01

    The thesis provides lessons learned from experiments conducted by the 11th Air Force to verify the capabilities of two vendor-produced Radar Data Management Systems (RDMS). The first part of the thesis provides background information explaining the impetus for such experiments and why a lessons learned approach was taken. The experimental plan and the final report from the PACAF experiments are analyzed using evaluation tools taught in the C3 curriculum at the Naval Postgraduate School. The lessons learned from the mistakes made during these experiments are applied to produce a revised experimental plan. A lessons learned section follows the analysis. This section discusses specific lessons learned from the 11th Air Force experiments as well as more general lessons learned by the author. The thesis concludes with two chapters that provide overall conclusions and a summary, and recommendations for future work that can be accomplished in the area of radar data management.

  13. Conducting real-time multiplayer experiments on the web.

    PubMed

    Hawkins, Robert X D

    2015-12-01

    Group behavior experiments require potentially large numbers of participants to interact in real time with perfect information about one another. In this paper, we address the methodological challenge of developing and conducting such experiments on the web, thereby broadening access to online labor markets as well as allowing for participation through mobile devices. In particular, we combine a set of recent web development technologies, including Node.js with the Socket.io module, HTML5 canvas, and jQuery, to provide a secure platform for pedagogical demonstrations and scalable, unsupervised experiment administration. Template code is provided for an example real-time behavioral game theory experiment which automatically pairs participants into dyads and places them into a virtual world. In total, this treatment is intended to allow those with a background in non-web-based programming to modify the template, which handles the technical server-client networking details, for their own experiments. PMID:25271089

  14. Thermal Conductivity of Polycrystalline PbTe with PbSe Nanoparticle Additives

    NASA Astrophysics Data System (ADS)

    Steward, Ian M.; Dyck, Jeffrey S.; Zhao, Yixin; Burda, Clemens

    2008-03-01

    Thermoelectric materials (TEMs) are semiconductor materials that use the Seebeck and Peltier effects to convert a temperature difference into an electric potential and vice versa. All thermoelectric materials are characterized by a figure of merit, ZT, which is directly correlated to the thermoelectric energy conversion efficiency. One option to obtain improved ZT values is to lower the thermal conductivity of the TEM. Nanostructuring of traditional TEMs is one avenue toward lowering thermal conductivity, hopefully without significantly diminishing the electrical properties. Pellets of bulk, polycrystalline lead telluride with varying concentrations of PbSe nanoparticle additives were prepared by pressing mixed powders. Measurements of thermal conductivity were performed in the temperature range 6 K -- 300 K. The data were compared to a theoretical model in an attempt to link the temperature dependent behavior of the thermal conductivity to the synthesis parameters, nanoparticle concentration, and sample morphology as revealed through Scanning Electron Microscope images.

  15. Effect of Cd Addition in Band Gap and Volume Conductivity of SeTe Based Glasses

    NASA Astrophysics Data System (ADS)

    Saraswat, Vibhav K.; Kishore, V.; Saraswat, Y. K.; Saxena, N. S.

    2011-10-01

    Presented paper discusses the variation in optical band gap and volume dc conductivity of Se-Te-Cd ternary Chalcogenide glasses as a function of concentration of Cd i.e. the composition of the glasses. Also, the temperature dependence of volume conductivity has been studied. The amorphous nature of these glasses has been confirmed by XRD patterns. Keithley Electrometer/High resistance meter 6517A was used in its FVMI mode to record I_V characteristics at different temperatures. Variation in conductivity, derived from I_V curves, as a function of composition of sample could be accounted for the bonds formed in the system. Additionally, the Poole-Frenkel conduction mechanism has also been verified in order to investigate the good agreement with the established fact that most of Chalcogenide glasses obey the Poole-Frenkel conduction mechanism. Absorption spectra were recorded using Ocean Optics USB2000 spectrophotometer in visible region. Band gap calculation using Tauc relation reveals that the system under test is semi-conducting in nature. The observed results are found to be in good agreement with each other.

  16. Influence of dry mixing and distribution of conductive additives in cathodes for lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Bauer, Werner; Nötzel, Dorit; Wenzel, Valentin; Nirschl, Hermann

    2015-08-01

    Conductive additives, like carbon black or graphite, are essential components of lithium ion batteries due to the limited electrical conductivity of most electrode materials. However, there is still a lack of knowledge about the optimized distribution of these materials within the electrode. A dry mixing process is used in order to prepare a conductive coating by depositing carbon black on the surface of Li(Ni1/3Mn1/3Co1/3)O2 (NMC) cathode particles. It is demonstrated that this - from a theoretically point of view - favorable distribution does not allow the preparation of working electrodes without taking into account the role of the binder. After adding an organic binder to the slurry, the polymer deposits on top of the carbon shell during drying and inhibits the conductive contact between the particles. This can be avoided by a fraction of distributed carbon particles which are associated with the binder phase providing conductive paths through the isolating organic material. It is shown that carbon black and graphite are principally fulfilling this task, but both materials are leading to varying processing behavior and electrode properties.

  17. Effect of small additions of carbon nanotubes on the electrical conductivity of polyurethane elastomer

    NASA Astrophysics Data System (ADS)

    Novikov, G. F.; Rabenok, E. V.; Estrin, Ya. I.; Ol'hov, Yu. A.; Badamshina, E. R.

    2014-10-01

    The effect of small (0.002-0.018 wt %) additions of single-walled carbon nanotubes on the dielectric properties and electrical conductivity of crosslinked polyurethane elastomer is studied in the temperature range of 133-453 K and the 10-3 to 105 Hz range of electric field frequencies. It is shown that the dependence of direct current conductivity σ dc on temperature deviates significantly from the Arrhenius dependence and is described by the Vogel-Fulcher-Tamman equation σ dc = σ dc0exp{- DT 0/( T - T 0)}, where T 0 is the Vogel temperature and D is the strength parameter. A correlation is found between the nonmonotonic dependences of the glass transition temperature ( T g), D parameter, and σ dc and the concentration of nanotubes with earlier results for their effects on the physicomechanical characteristics (strength and Young's modulus) of these systems.

  18. Response of non-added solutes during nutrient addition experiments in streams

    NASA Astrophysics Data System (ADS)

    Rodriguez-Cardona, B.; Wymore, A.; Koenig, L.; Coble, A. A.; McDowell, W. H.

    2015-12-01

    Nutrient addition experiments, such as Tracer Additions for Spiraling Curve Characterization (TASCC), have become widely popular as a means to study nutrient uptake dynamics in stream ecosystems. However, the impact of these additions on ambient concentrations of non-added solutes is often overlooked. TASCC addition experiments are ideal for assessing interactions among solutes because it allows for the characterization of multiple solute concentrations across a broad range of added nutrient concentrations. TASCC additions also require the addition of a conservative tracer (NaCl) to track changes in conductivity during the experimental manipulation. Despite its use as a conservative tracer, chloride (Cl) and its associated sodium (Na) might change the concentrations of other ions and non-added nutrients through ion exchange or other processes. Similarly, additions of biologically active solutes might change the concentrations of other non-added solutes. These methodological issues in nutrient addition experiments have been poorly addressed in the literature. Here we examine the response of non-added solutes to pulse additions (i.e. TASCC) of NaCl plus nitrate (NO3-), ammonium, and phosphate across biomes including temperate and tropical forests, and arctic taiga. Preliminary results demonstrate that non-added solutes respond to changes in the concentration of these added nutrients. For example, concentrations of dissolved organic nitrogen (DON) in suburban headwater streams of New Hampshire both increase and decrease in response to NO3- additions, apparently due to biotic processes. Similarly, cations such as potassium, magnesium, and calcium also increase during TASCC experiments, likely due to cation exchange processes associated with Na addition. The response of non-added solutes to short-term pulses of added nutrients and tracers needs to be carefully assessed to ensure that nutrient uptake metrics are accurate, and to detect biotic interactions that may

  19. CMB topography and electrical conductivity as additional constraints for the lowermost mantle thermo-chemical structure

    NASA Astrophysics Data System (ADS)

    Deschamps, F.; Yin, Y.; Tackley, P. J.

    2013-12-01

    A variety of seismic observations, including tomographic models, indicate that the lowermost mantle is strongly heterogeneous. Seismic observations further support a thermo-chemical origin for the large scale heterogeneities. In particular, the large low-shear wave velocity provinces (LLSVP) observed by global tomographic images are better explained by a combination of thermal and chemical anomalies. Despite the accuracy of seismic information, uncertainties and trade-off still prevent the determination of a detailed lower mantle thermo-chemical structure. For instance, the nature of chemical heterogeneities and the exact role played by the post-perovskite phase transition are still debated. Additional constraints are needed to discriminate between the possible models of structure and dynamics of the lower mantle. Here, we consider two potential additional constraints, the electrical conductivity and the dynamic topography at the core-mantle boundary (CMB). Unlike density and seismic velocities, electrical conductivity increases with temperature. In addition, it strongly varies with the iron and silicate content. Using appropriate mineral physics data, we calculated a 3D distribution of electrical conductivity in lower mantle from the thermo-chemical structure inferred by probabilistic tomography, which maps iron and silicate excess in the LLSVP. In the lowermost mantle, we observe a belt of high conductivity, with maximum values around 20 S/m located in the LLSVP. Such a belt may trigger electric currents in the lowermost mantle and induce magnetic field variations with period of one year or more. It may thus be seen by global models of electrical conductivity. Unfortunately, such models do not sample yet regions deeper than 2000 km. A second, independent constraint we explored is the dynamic topography at the CMB. We used stagYY to calculate the dynamic topography associated with several models of thermo-chemical convection, and observe strong differences

  20. A theoretical study of wave dispersion and thermal conduction for HMX/additive interfaces

    NASA Astrophysics Data System (ADS)

    Long, Yao; Chen, Jun

    2014-04-01

    The wave dispersion rule for non-uniform material is useful for ultrasonic inspection and engine life prediction, and also is key in achieving an understanding of the energy dissipation and thermal conduction properties of solid material. On the basis of linear response theory and molecular dynamics, we derive a set of formulas for calculating the wave dispersion rate of interface systems, and study four kinds of interfaces inside plastic bonded explosives: HMX/{HMX, TATB, F2312, F2313}. (HMX: octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine; TATB: 1,3,5-triamino-2,4,6-trinitrobenzene; F2312, F2313: fluoropolymers). The wave dispersion rate is obtained over a wide frequency range from kHz to PHz. We find that at low frequency, the rate is proportional to the square of the frequency, and at high frequency, the rate couples with the molecular vibration modes at the interface. By using the results, the thermal conductivities of HMX/additive interfaces are derived, and a physical model is built for describing the total thermal conductivity of mixture explosives, including HMX multi-particle systems and {TATB, F2312, F2313}-coated HMX.

  1. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  2. Propulsion Integrated Vehicle Health Management Technology Experiment (PITEX) Conducted

    NASA Technical Reports Server (NTRS)

    Maul, William A.; Chicatelli, Amy K.; Fulton, Christopher E.

    2004-01-01

    The Propulsion Integrated Vehicle Health Management (IVHM) Technology Experiment (PITEX) is a continuing NASA effort being conducted cooperatively by the NASA Glenn Research Center, the NASA Ames Research Center, and the NASA Kennedy Space Center. It was a key element of a Space Launch Initiative risk-reduction task performed by the Northrop Grumman Corporation in El Segundo, California. PITEX's main objectives are the continued maturation of diagnostic technologies that are relevant to second generation reusable launch vehicle (RLV) subsystems and the assessment of the real-time performance of the PITEX diagnostic solution. The PITEX effort has considerable legacy in the NASA IVHM Technology Experiment for X-vehicles (NITEX) that was selected to fly on the X-34 subscale RLV that was being developed by Orbital Sciences Corporation. NITEX, funded through the Future-X Program Office, was to advance the technology-readiness level of selected IVHM technologies within a flight environment and to begin the transition of these technologies from experimental status into RLV baseline designs. The experiment was to perform realtime fault detection and isolation and suggest potential recovery actions for the X-34 main propulsion system (MPS) during all mission phases by using a combination of system-level analysis and detailed diagnostic algorithms.

  3. Progress photograph of sample experiments being conducted with lunar material

    NASA Technical Reports Server (NTRS)

    1969-01-01

    A progress photograph of sample experiments being conducted in the Manned Spacecraft Center's Lunar Receiving Laboratory with lunar material brought back to Earth by the crew of the Apollo 11 mission. Aseptic cultures of liverwort (marchantia polymorpha) - a species of plant commonly found growing on rocks or in wooded areas - are shown in two rows of sample containers. Seven weeks or some 50 days prior to this photograph 0.22 grams of finely ground lunar material was added to each of the upper samples of cultures. The lower cultures were untreated, and a noted difference can be seen in the upper row and the lower one, both in color and size of the culture.

  4. Modification of sandy soil hydrophysical environment through bagasse additive under laboratory experiment

    NASA Astrophysics Data System (ADS)

    Abd El-Halim, A. A.; Kumlung, Arunsiri

    2015-01-01

    Until now sandy soils can be considered as one roup having common hydrophysical problems. Therefore, a laboratory experiment was conducted to evaluate the influence of bagasse as an amendment to improve hydrophysical properties of sandy soil, through the determination of bulk density, aggregatesize distribution, total porosity, hydraulic conductivity, pore-space structure and water retention. To fulfil this objective, sandy soils were amended with bagasse at the rate of 0, 0.5, 1, 2, 3 and 4% on the dry weight basis. The study results demonstrated that the addition of bagasse to sandy soils in between 3 to 4% on the dry weight basis led to a significant decrease in bulk density, hydraulic conductivity, and rapid-drainable pores, and increase in the total porosity, water-holding pores, fine capillary pores, water retained at field capacity, wilting point, and soil available water as compared with the control treatment

  5. Software reliability: Additional investigations into modeling with replicated experiments

    NASA Technical Reports Server (NTRS)

    Nagel, P. M.; Schotz, F. M.; Skirvan, J. A.

    1984-01-01

    The effects of programmer experience level, different program usage distributions, and programming languages are explored. All these factors affect performance, and some tentative relational hypotheses are presented. An analytic framework for replicated and non-replicated (traditional) software experiments is presented. A method of obtaining an upper bound on the error rate of the next error is proposed. The method was validated empirically by comparing forecasts with actual data. In all 14 cases the bound exceeded the observed parameter, albeit somewhat conservatively. Two other forecasting methods are proposed and compared to observed results. Although demonstrated relative to this framework that stages are neither independent nor exponentially distributed, empirical estimates show that the exponential assumption is nearly valid for all but the extreme tails of the distribution. Except for the dependence in the stage probabilities, Cox's model approximates to a degree what is being observed.

  6. Experiments on thermal contact conductance between metals below 100 K

    NASA Astrophysics Data System (ADS)

    Choi, Yeon Suk; Kim, Myung Su

    2014-01-01

    The thermal contact conductance is one of the important components in heat transfer mechanism. The accurate estimation of thermal contact conductance is necessary for the development of a conduction-cooled superconducting magnet system because the metallic materials are thermally connected to the refrigerator or heat sink to cool the superconducting magnet without cryogen. The contact resistance occurs at the interface between metals and the amount of conductance can be affected by various factors, such as surface roughness, contact area, and contact pressure. In the superconducting magnet system, there are several metal components in contact with each other for cooling magnet as well as supplying current to the magnet. Therefore, a temperature gradient exists between superconducting magnet and cryocooler. In this study, we have developed the thermal contact conductance measurement system and used the steady state method to measure the thermal conductance between metals. The effects of temperature, contact pressure and interfacial materials on the thermal contact conductance are also discussed.

  7. Additional support for the existence of skin conductance responses at unconditioned stimulus omission.

    PubMed

    Spoormaker, Victor I; Blechert, Jens; Goya-Maldonado, Roberto; Sämann, Philipp G; Wilhelm, Frank H; Czisch, Michael

    2012-11-15

    The existence of a skin conductance response to an expected but omitted aversive stimulus has recently been challenged. To counter this claim, we provide a review of the literature and a temporal analysis of two independent skin conductance data sets during aversive conditioning and extinction that demonstrates a consistent and reproducible skin conductance response at omission of an anticipated aversive stimulus. The validity of this so-called unconditioned stimulus (US) omission response is relevant for skin conductance modeling in the context of neuroimaging and more generally for conditioning theory. PMID:22922467

  8. Stories from the trenches: Experiences of Alberta pharmacists in obtaining additional prescribing authority

    PubMed Central

    Charrois, Theresa; Rosenthal, Meagen; Tsuyuki, Ross T.

    2012-01-01

    Background: Pharmacists in Alberta can apply to the Alberta College of Pharmacists in order to obtain the designation of additional prescriber. This designation uniquely allows them to initiate therapy, in addition to other medication-related activities. Our objective was to examine specific experiences of pharmacists regarding the decision to apply and the application itself, and use this information to help inform other pharmacists who are considering additional prescribing. Methods: All pharmacists involved in a randomized, controlled trial being conducted in rural Alberta who had received their additional prescribing authorization (APA) were invited to participate. Pharmacists were contacted via e-mail and asked to respond to questions regarding their experiences in applying for APA. Responses were analyzed using content analysis and the identites of all respondents were kept anonymous. Results: Fourteen pharmacists were invited to participate. Review and examination of the responses revealed 3 main themes: motivation, hurdles and outcomes. Motivation can be understood as the reasons why they applied for their APA. Hurdles include any problems encountered of a personal, environmental or professional nature. Outcomes refer to how this designation has changed their practice. Discussion: Pharmacists had to address many factors that were unexpected during the application process; however, the eventual outcome of obtaining APA was deemed beneficial, both professionally and with regard to patient care. Conclusion: The information shared from these pharmacists will help other pharmacists, regardless of jurisdiction, overcome some of the challenges associated with obtaining advanced prescribing privileges. PMID:23509485

  9. Conductive network formation of carbon nanotubes in elastic polymer microfibers and its effect on the electrical conductance: Experiment and simulation

    NASA Astrophysics Data System (ADS)

    Cho, Hyun Woo; Kim, Sang Won; Kim, Jeongmin; Kim, Un Jeong; Im, Kyuhyun; Park, Jong-Jin; Sung, Bong June

    2016-05-01

    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 upon 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.

  10. Conductive network formation of carbon nanotubes in elastic polymer microfibers and its effect on the electrical conductance: Experiment and simulation.

    PubMed

    Cho, Hyun Woo; Kim, Sang Won; Kim, Jeongmin; Kim, Un Jeong; Im, Kyuhyun; Park, Jong-Jin; Sung, Bong June

    2016-05-21

    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 upon 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. PMID:27208970

  11. Experiment of electrical conductivity at low temperature (preliminary measurement)

    SciTech Connect

    Zhao, Y.; Wang, H.

    1998-07-01

    A muon collider needs very large amount of RF power, how to reduce the RF power consumption is of major concern. Thus the application of liquid nitrogen cooling has been proposed. However, it is known that the electrical conductivity depends on many factors and the data from different sources vary in a wide range, especially the data of conductivity of beryllium has no demonstration in a real application. Therefore it is important to know the conductivity of materials, which are commercially available, and at a specified frequency. Here, the results of the preliminary measurement on the electrical conductivity of copper at liquid nitrogen temperature are summarized. Addressed also are the data fitting method and the linear expansion of copper.

  12. Improving the Thermal Conductivity of UO2 Fuel with the Addition of Graphite Fibers

    SciTech Connect

    Hollenbach, Daniel F; Ott, Larry J

    2010-01-01

    The commercial nuclear power industry is investing heavily in advanced fuels that can produce higher power levels with a higher safety margin and be manufactured at low cost. Although chemically stable and inexpensive to manufacture, UO2 fuel is limited by its thermal conductivity. If the fuel thermal conductivity could be increased, existing nuclear reactors would be able to operate at higher powers and new reactors could be designed with higher power densities, thus decreasing the overall cost of electricity and the number of new electrical generating plants needed to meet demand. Movement to higher U-235 enrichments and fuel burnups is limited by UO2 thermal conductivity, which decreases with fuel burnup. Preliminary studies indicate that adding 1% to 5% by volume of long, thin fibers having a high thermal conductivity can substantially increase the bulk thermal conductivity of standard UO2 fuel with minimal decreases in its fissile inventory. The fibers need to remain intact to act as the primary path for transferring heat energy out of the fuel and therefore need to not chemically interact with the UO2 fuel.

  13. How to Conduct Clinical Qualitative Research on the Patient's Experience

    ERIC Educational Resources Information Center

    Chenail, Ronald J.

    2011-01-01

    From a perspective of patient-centered healthcare, exploring patients' (a) preconceptions, (b) treatment experiences, (c) quality of life, (d) satisfaction, (e) illness understandings, and (f) design are all critical components in improving primary health care and research. Utilizing qualitative approaches to discover patients' experiences can…

  14. COLUMN EXPERIMENTS AND ANOMALOUS CONDUCTIVITY IN HYDROCARBON-IMPACTED SOILS

    EPA Science Inventory

    A laboratory experiment was designed to increase the understanding of the geoelectric effects of microbial " degradation of hydrocarbons. Eight large columns were were paired to provide a replicate of each of four experiments. These large-volume columns contained "sterilized" soi...

  15. Results from the LDEF/A0076 cascaded variable conductance heatpipe experiment

    NASA Technical Reports Server (NTRS)

    Grote, Michael G.

    1992-01-01

    The A0076 Variable Conductance Heat Pipe Experiment (CVCHPE) on the Long Duration Exposure Facility (LDEF) demonstrated temperature control better than +/- 0.3 C during fifty days on on-orbit data collection in a widely varying external environment. The experiment used two series connected, dry reservoir variable conductance heat pipes which require no electrical power for operation. The heat pipes used a central artery design with ammonia working fluid and nitrogen control gas. The LDEF was in orbit for almost six years rather than the planned one year mission. Although no additional data were taken during this extended period, post-test data indicated that the set point drifted upward less than 1 C per year. There were significant changes to the appearance of all external thermal control surfaces primarily due to atomic oxygen degradation, and one small anomaly in the electronics. These changes, though, had little effect on the CVCHPE performance.

  16. Scaling of material properties for Yucca Mountain: literature review and numerical experiments on saturated hydraulic conductivity

    SciTech Connect

    McKenna, S.A.; Rautman, C.A.

    1996-08-01

    A review of pertinent literature reveals techniques which may be practical for upscaling saturated hydraulic conductivity at Yucca Mountain: geometric mean, spatial averaging, inverse numerical modeling, renormalization, and a perturbation technique. Isotropic realizations of log hydraulic conductivity exhibiting various spatial correlation lengths are scaled from the point values to five discrete scales through these techniques. For the variances in log{sub 10} saturated hydraulic conductivity examined here, geometric mean, numerical inverse and renormalization adequately reproduce point scale fluxes across the modeled domains. Fastest particle velocities and dispersion measured on the point scale are not reproduced by the upscaled fields. Additional numerical experiments examine the utility of power law averaging on a geostatistical realization of a cross-section similar to the cross-sections that will be used in the 1995 groundwater travel time calculations. A literature review on scaling techniques for thermal and mechanical properties is included. 153 refs., 29 figs., 6 tabs.

  17. HOW WELL ARE HYDRAULIC CONDUCTIVITY VARIATIONS APPROXIMATED BY ADDITIVE STABLE PROCESSES? (R826171)

    EPA Science Inventory

    Abstract

    Analysis of the higher statistical moments of a hydraulic conductivity (K) and an intrinsic permeability (k) data set leads to the conclusion that the increments of the data and the logs of the data are not governed by Levy-stable or Gaussian dis...

  18. Payload specialists Baudry and Al-Saud conduct Postural experiment

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Payload specialists Patrick Baudry (left) and Sultan Salman Abdelazize Al-Saud team up to conduct a French Postural Experement (FPE) on the middeck of the Space shuttle Discovery during the STS 51-G flight. Behind them on the middeck walls are two sleep restraints.

  19. Payload specialist Sultan Abdelazize Al-Saud conducts Postural experiment

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Payload specialist Sultan Salman Abdelazize Al-Saud assists in conducting a French Postural Experement (FPE) on the middeck of the Space shuttle Discovery during the STS 51-G flight. Behind him on the middeck walls are two sleep restraints. At the bottom of the frame, foot restraints are visible.

  20. Effect of alkali addition on DC conductivity and thermal properties of vanadium-bismo-borate glasses

    SciTech Connect

    Khasa, S. Dahiya, M. S.; Agarwal, A.

    2014-04-24

    The DC Conductivity and Differential Thermal Analysis of glasses with composition (30−x)Li{sub 2}O⋅xV{sub 2}O{sub 5}⋅20Bi{sub 2}O{sub 3}⋅50B{sub 2}O{sub 3}(x=15, 10, 5) has been carried out in order to study the effect of replacing the Transition Metal Oxide (TMO) with alkali oxide. A significant increase in the DC conductivity has been observed with increase in alkali content. Again the thermal measurements have shown the decrease in both glass transition temperature (T{sub g}) and crystallization temperature (T{sub x}). The Glass Stability (GS) and Glass Forming Ability (GFA) have also been calculated and these also were found to decrease with increase in alkali oxide content at the cost of TMO.

  1. An alloy solidification experiment conducted on Shenzhou spacecraft

    NASA Astrophysics Data System (ADS)

    Huang, Q.; Luo, X.-H.; Li, Y.-Y.

    To gain a better understanding of how gravity-driven phenomena affect the solidification and crystal growth of metallic materials, directional solidification experiments have been performed on an Al-Al 3Ni eutectic alloy and an Al-Bi monotectic alloy on board the unmanned Chinese Shenzhou III spacecraft during its flight. For sake of comparison, identical experiments were also performed in the laboratory on earth. The results of investigations applying metallographic, SEM, EPMA and image analysis techniques are reported. Some interesting differences between the samples solidified in space and their counterparts solidified on the ground are described.

  2. Astronaut Mike Fincke Conducts Fluid Merging Viscosity Measurement (FMVM) Experiment

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Astronaut Mike Fincke places droplets of honey onto the strings for the Fluid Merging Viscosity Measurement (FMVM) investigation onboard the International Space Station (ISS). The FMVM experiment measures the time it takes for two individual highly viscous fluid droplets to coalesce or merge into one droplet. Different fluids and droplet size combinations were tested in the series of experiments. By using the microgravity environment, researchers can measure the viscosity or 'thickness' of fluids without the influence of containers and gravity using this new technique. Understanding viscosity could help scientists understand industrially important materials such as paints, emulsions, polymer melts and even foams used to produce pharmaceutical, food, and cosmetic products.

  3. Status of the Nuclear-Induced Conductivity Experiment (NICE) Project

    NASA Technical Reports Server (NTRS)

    Bitteker, Leo; Bragg-Sitton, Shannon M.; Litchford, Ron J.; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    Nuclear-based magnetohydrodynamic (MHD) energy conversion has been pursued in various forms since the 1950's. The majority of this work was motivated by the compatibility of MHD generators with the high temperature achievable with a nuclear reactor and the associated potential for very high cycle efficiency. As a result of this perspective, methods for enhancing the electrical conductivity of the MHD flow have primarily focused on traditional thermal ionization processes, especially those utilizing alkali metal seeds. However, electrical conductivity enhancement via thermal interactions imposes significant limitations on the flow expansion through the generator, and hence on the ultimate power density. Furthermore, the introduction of an alkali metal seed into the flow significantly complicates the engineering design and increases the potential for system failures due to plating of the evaporated metal on cold surfaces.

  4. Lunar electrical conductivity, permeability and temperature from Apollo magnetometer experiments

    NASA Technical Reports Server (NTRS)

    Dyal, P.; Parkin, C. W.; Daily, W. D.

    1977-01-01

    Magnetometers were deployed at four Apollo sites on the moon to measure remanent and induced lunar magnetic fields. Measurements from this network of instruments were used to calculate the electrical conductivity, temperature, magnetic permeability, and iron abundance of the lunar interior. The measured lunar remanent fields range from 3 gammas minimum at the Apollo 15 site to 327 gammas maximum at the Apollo 16 site. Simultaneous magnetic field and solar plasma pressure measurements show that the remanent fields at the Apollo 12 and 16 sites interact with, and are compressed by, the solar wind. Remanent fields at Apollo 12 and Apollo 16 are increased 16 gammas and 32 gammas, respectively, by a solar plasma bulk pressure increase of 1.5 X 10 to the -7th power dynes/sq cm. Global lunar fields due to eddy currents, induced in the lunar interior by magnetic transients, were analyzed to calculate an electrical conductivity profile for the moon. From nightside magnetometer data in the solar wind it was found that deeper than 170 km into the moon the conductivity rises from .0003 mhos/m to .10 mhos/m at 100 km depth. Recent analysis of data obtained in the geomagnetic tail, in regions free of complicating plasma effects, yields results consistent with nightside values.

  5. Using Phenomenology to Conduct Environmental Education Research: Experience and Issues

    ERIC Educational Resources Information Center

    Nazir, Joanne

    2016-01-01

    Recently, I applied a phenomenological methodology to study environmental education at an outdoor education center. In this article, I reflect on my experience of doing phenomenological research to highlight issues researchers may want to consider in using this type of methodology. The main premise of the article is that phenomenology, with its…

  6. Additional experiments on flowability improvements of aviation fuels at low temperatures, volume 2

    NASA Technical Reports Server (NTRS)

    Stockemer, F. J.; Deane, R. L.

    1982-01-01

    An investigation was performed to study flow improver additives and scale-model fuel heating systems for use with aviation hydrocarbon fuel at low temperatures. Test were performed in a facility that simulated the heat transfer and temperature profiles anticipated in wing fuel tanks during flight of long-range commercial aircraft. The results are presented of experiments conducted in a test tank simulating a section of an outer wing integral fuel tank approximately full-scale in height, chilled through heat exchange panels bonded to the upper and lower horizontal surfaces. A separate system heated lubricating oil externally by a controllable electric heater, to transfer heat to fuel pumped from the test tank through an oil-to-fuel heat exchanger, and to recirculate the heated fuel back to the test tank.

  7. Mini-columns for Conducting Breakthrough Experiments. Design and Construction

    SciTech Connect

    Dittrich, Timothy M.; Reimus, Paul William; Ware, Stuart Douglas

    2015-06-11

    Experiments with moderately and strongly sorbing radionuclides (i.e., U, Cs, Am) have shown that sorption between experimental solutions and traditional column materials must be accounted for to accurately determine stationary phase or porous media sorption properties (i.e., sorption site density, sorption site reaction rate coefficients, and partition coefficients or Kd values). This report details the materials and construction of mini-columns for use in breakthrough columns to allow for accurate measurement and modeling of sorption parameters. Material selection, construction techniques, wet packing of columns, tubing connections, and lessons learned are addressed.

  8. Parameters and pitfalls to consider in the conduct of food additive research, Carrageenan as a case study.

    PubMed

    Weiner, Myra L

    2016-01-01

    This paper provides guidance on the conduct of new in vivo and in vitro studies on high molecular weight food additives, with carrageenan, the widely used food additive, as a case study. It is important to understand the physical/chemical properties and to verify the identity/purity, molecular weight and homogeneity/stability of the additive in the vehicle for oral delivery. The strong binding of CGN to protein in rodent chow or infant formula results in no gastrointestinal tract exposure to free CGN. It is recommended that doses of high Mw non-caloric, non-nutritive additives not exceed 5% by weight of total solid diet to avoid potential nutritional effects. Addition of some high Mw additives at high concentrations to liquid nutritional supplements increases viscosity and may affect palatability, caloric intake and body weight gain. In in vitro studies, the use of well-characterized, relevant cell types and the appropriate composition of the culture media are necessary for proper conduct and interpretation. CGN is bound to media protein and not freely accessible to cells in vitro. Interpretation of new studies on food additives should consider the interaction of food additives with the vehicle components and the appropriateness of the animal or cell model and dose-response. PMID:26615870

  9. Conducting Closed Habitation Experiments: Experience from the Lunar Mars Life Support Test Project

    NASA Technical Reports Server (NTRS)

    Barta, Daniel J.; Edeen, Marybeth A.; Henninger, Donald L.

    2004-01-01

    The Lunar-Mars Life Support Test Project (LMLSTP) was conducted from 1995 through 1997 at the National Aeronautics and Space Administration s (NASA) Johnson Space Center (JSC) to demonstrate increasingly longer duration operation of integrated, closed-loop life support systems that employed biological and physicochemical techniques for water recycling, waste processing, air revitalization, thermal control, and food production. An analog environment for long-duration human space travel, the conditions of isolation and confinement also enabled studies of human factors, medical sciences (both physiology and psychology) and crew training. Four tests were conducted, Phases I, II, IIa and III, with durations of 15, 30,60 and 91 days, respectively. The first phase focused on biological air regeneration, using wheat to generate enough oxygen for one experimental subject. The systems demonstrated in the later phases were increasingly complex and interdependent, and provided life support for four crew members. The tests were conducted using two human-rated, atmospherically-closed test chambers, the Variable Pressure Growth Chamber (VPGC) and the Integrated Life Support Systems Test Facility (ILSSTF). Systems included test articles (the life support hardware under evaluation), human accommodations (living quarters, kitchen, exercise equipment, etc.) and facility systems (emergency matrix system, power, cooling, etc.). The test team was managed by a lead engineer and a test director, and included test article engineers responsible for specific systems, subsystems or test articles, test conductors, facility engineers, chamber operators and engineering technicians, medical and safety officers, and science experimenters. A crew selection committee, comprised of psychologists, engineers and managers involved in the test, evaluated male and female volunteers who applied to be test subjects. Selection was based on the skills mix anticipated for each particular test, and utilized

  10. Conducting Closed Habitation Experiments: Experience from the Lunar Mars Life Support Test Project

    NASA Technical Reports Server (NTRS)

    Barta, Daniel J.; Edeen, Marybeth A.; Henninger, Donald L.

    2006-01-01

    The Lunar-Mars Life Support Test Project (LMLSTP) was conducted from 1995 through 1997 at the National Aeronautics and Space Administration s (NASA) Johnson Space Center (JSC) to demonstrate increasingly longer duration operation of integrated, closed-loop life support systems that employed biological and physicochemical techniques for water recycling, waste processing, air revitalization, thermal control, and food production. An analog environment for long-duration human space travel, the conditions of isolation and confinement also enabled studies of human factors, medical sciences (both physiology and psychology) and crew training. Four tests were conducted, Phases I, II, IIa and III, with durations of 15, 30, 60 and 91 days, respectively. The first phase focused on biological air regeneration, using wheat to generate enough oxygen for one experimental subject. The systems demonstrated in the later phases were increasingly complex and interdependent, and provided life support for four crew members. The tests were conducted using two human-rated, atmospherically-closed test chambers, the Variable Pressure Growth Chamber (VPGC) and the Integrated Life Support Systems Test Facility (ILSSTF). Systems included test articles (the life support hardware under evaluation), human accommodations (living quarters, kitchen, exercise equipment, etc.) and facility systems (emergency matrix system, power, cooling, etc.). The test team was managed by a lead engineer and a test director, and included test article engineers responsible for specific systems, subsystems or test articles, test conductors, facility engineers, chamber operators and engineering technicians, medical and safety officers, and science experimenters. A crew selection committee, comprised of psychologists, engineers and managers involved in the test, evaluated male and female volunteers who applied to be test subjects. Selection was based on the skills mix anticipated for each particular test, and utilized

  11. Investigating the effects of conductivity on zone overlap with EMMA: computer simulation and experiment.

    PubMed

    Stahl, John W; Catherman, Adam D; Sampath, Ranasinghe K; Seneviratne, C Aravinda; Strein, Timothy G

    2011-06-01

    In this paper, we demonstrate, using both experiment and simulation, how sample zone conductivity can affect plug-plug mixing in small molecule applications of electrophoretically mediated microanalysis (EMMA). The effectiveness of in-line mixing, which is driven by potential, can vary widely with experimental conditions. Using two small molecule systems, the effects of local conductivity differences between analyte plugs, reagent plugs and the BGE on EMMA analyses are examined. Simul 5.0, a dynamic simulation program for CE systems, is used to understand the ionic boundaries and profiles that give rise to the experimentally obtained data for EMMA analyses for (i) creatinine determination via the Jaffe reaction, a reaction involving a neutral and an anion, and (ii) the redox reaction between gallate and 2,6-dichloroindophenol, two anions. Low sample conductivity, which is widely used in CE analyses, can be detrimental for in-line reactions involving a neutral reactant, as rapid migration of the ionic component across a low conductivity neutral zone results in poor reagent plug overlap and low reaction efficiency. Conversely, with two similarly charged reagents, a low conductivity sample plug is advantageous, as it allows field-amplified stacking of the reagents into a tight reaction zone. In addition, the complexity of simultaneously overlapping three reagent zones is considered, and experimental results validate the predictions made by the simulation. The simulations, however, do not appear to predict all of the observed experimental behavior. Overall, by combining experiment with simulation, an enhanced appreciation for the local field effects in EMMA is realized, and general guidelines for an advantageous sample matrix can be established for categories of EMMA analyses. PMID:21563180

  12. Heat, Light, and Videotapes: Experiments in Heat Conduction Using Liquid Crystal Film.

    ERIC Educational Resources Information Center

    Bacon, Michael E.; And Others

    1995-01-01

    Presents a range of experiments in heat conduction suitable for upper-level undergraduate laboratories that make use of heat sensitive liquid crystal film to measure temperature contours. Includes experiments mathematically described by Laplace's equation, experiments theoretically described by Poisson's equation, and experiments that involve…

  13. Additive Fabrication of Conductive Patterns by a Template Transfer Process Based on Benzotriazole Adsorption As a Separation Layer.

    PubMed

    Chang, Yu; Yang, Zhen-Guo

    2016-06-01

    The traditional subtractive process to fabricate conductive patterns is environmentally harmful, wasteful, and limited in line width. The additive process, including direct printing of conductive paste or ink, direct printing of catalytic ink, laser-induced forward transfer, etc., can solve these problems. However, the current additive process also faces many difficulties such as low electrical and adhesion properties, low pattern thickness, high cost, etc. Benzotriazole (BTA), as widely used corrosion inhibitor, can be adsorbed onto a copper surface. The electroplated copper film on BTA-adsorbed copper foil shows poor adhesion. On the basis of this phenomenon, a novel template transfer process to additively fabricate conductive patterns has been developed. A permeant antiadhesive mask is printed on carrier copper foil, and then, BTA is adsorbed onto the exposed area of the carrier foil, thus forming the template. The template is electroplated to grow conductive patterns in the exposed parts, and then can be adhered to the flexible substrate. The substrate is peeled off, with the transfer of the conductive patterns to the substrate, to form the designed conductive patterns on PET. By reimmersing the template into BTA solution, the template can be used again. The mechanism of BTA adsorption and the reason for the low peeling strength are researched using Raman spectra, XPS and electrochemical impedance spectroscopy. Copper patterns more than 20 μm in thickness can be prepared on PET, the resistivity of the prepared copper patterns is 2.01 μΩ cm, which is about the same as bulk copper, and the peeling strength of the pattern on PET is measured to be 6.97 N/cm. This template transfer process, with no waste, low pollution, high electrical and adhesion properties, and low cost, shows high potential in the large scale manufacturing of electronic devices, such as RFID circuitry, FPCs, etc. PMID:27171553

  14. The Additional-Mass Effect of Plates as Determined by Experiments

    NASA Technical Reports Server (NTRS)

    Gracey, William

    1941-01-01

    The apparent increase in the inertia properties of a body moving in a fluid medium has been called the additional-mass effect. This report presents a resume of test procedures and results of experimental determinations of the additional-mass effect of flat plates. In addition to data obtained from various foreign sources and from a NACA investigation in 1933, the results of tests recently conducted by the National Advisory Committee for Aeronautics are included.

  15. Gas Chromatographic Determination of Methyl Salicylate in Rubbing Alcohol: An Experiment Employing Standard Addition.

    ERIC Educational Resources Information Center

    Van Atta, Robert E.; Van Atta, R. Lewis

    1980-01-01

    Provides a gas chromatography experiment that exercises the quantitative technique of standard addition to the analysis for a minor component, methyl salicylate, in a commercial product, "wintergreen rubbing alcohol." (CS)

  16. Voices from the Classroom: Experiences of Teachers of Deaf Students with Additional Disabilities

    ERIC Educational Resources Information Center

    Musyoka, Millicent Malinda; Gentry, Mary Anne; Bartlett, James Joseph

    2016-01-01

    The purpose of this research is to investigate experiences of K-12 classroom teachers of deaf students with additional disabilities. Today, more deaf and hard of hearing students are identified as having additional disabilities (Bruce, DiNatale & Ford, 2008; Ewing, 2011; Gallaudet Research Institute, 2011; Jones, Jones & Ewing, 2006;…

  17. Stimulated Raman scatter analyses of experiments conducted at the National Ignition Facility

    SciTech Connect

    Hinkel, D. E.; Rosen, M. D.; Williams, E. A.; Langdon, A. B.; Still, C. H.; Callahan, D. A.; Moody, J. D.; Michel, P. A.; Town, R. P. J.; London, R. A.; Langer, S. H.

    2011-05-15

    Recent experiments conducted at the National Ignition Facility achieved two main goals: providing radiation drive and symmetry suitable for subsequent ignition experiments. Of the many diagnostics fielded, one provided a time-resolved wavelength spectrum of light reflected from the target by stimulated Raman scatter (SRS). SRS occurs when incident light reflects off self-generated electron plasma waves. Analyses indicate that synthetic SRS spectra better match those of experiments when an atomic physics model with greater emissivity is utilized in target modeling, along with less inhibited electron transport (higher flux, with, ideally, nonlocal electron transport). With these models, SRS occurs in a target region where nearest-neighbor quads of laser beams significantly overlap the diagnosed quad. This increases SRS gain at lower density (lower wavelength), a feature consistent with experimental results. Inclusion of this effect of multiple quads sharing a reflected SRS light wave has resulted in improved capabilities used to successfully predict (preshot) the SRS spectrum from the first target driven with 1.25 MJ of laser energy. Additional resonant amplification of SRS light in the overlap intensity region is demonstrated in beam propagation simulations. Such effects will be reduced in a target optimized for these less dense and cooler plasma conditions.

  18. The Effects of Various Conductive Additive and Polymeric Binder Contents on the Performance of a Lithium-ion Composite

    SciTech Connect

    Stevenson, Cynthia; Liu, G.; Zheng, H.; Kim, S.; Deng, Y.; Minor, A.M.; Song, X.; Battaglia, V.S.

    2008-08-07

    Fundamental electrochemical methods, cell performance tests, and physical characterization tests such as electron microscopy were used to study the effects of levels of the inert materials (acetylene black (AB), a nano-conductive additive, and polyvinylidene difluoride (PVDF), a polymer binder) on the power performance of lithium-ion composite cathodes. The electronic conductivity of the AB/PVDF composites at different compositions was measured with a four-point probe direct current method. The electronic conductivity was found to increase rapidly and plateau at a AB:PVDF ratio 0.2:1 (by weight), with 0.8:1 being the highest conductivity composition. AB:PVDF compositions along the plateau of 0.2:1, 0.4:1, 0.6:1 and 0.8:1 were investigated. Electrodes of each of those compositions were fabricated with different fractions of AB/PVDF to active material. It was found that at the 0.8:1 AB:PVDF, the rate performance improved with increases in the AB/PVDF loading, whereas at the 0.2:1 AB:PVDF, the rate performance improved with decreases in the AB/PVDF loading. The impedance of electrodes made with 0.6:1 AB:PVDF was low and relatively invariant.

  19. Effect of Copper/Graphite Addition on Electrical Conductivity and Thermal Insulation of Unsaturated Polyester/Jute Composites

    NASA Astrophysics Data System (ADS)

    Biswas, Bhabatosh; Chabri, Sumit; Mitra, Bhairab Chandra; Das, Kunal; Bandyopadhyay, Nil Ratan; Sinha, Arijit

    2016-02-01

    Jute fibre along with Cu particle reinforced unsaturated polyester composites having different filler loading viz. 2, 5, 10 and 15 wt% were fabricated by compression molding technique. In present investigation, it was observed that with fillers (Jute and Cu) incorporation, the electrical conductivity was monotonically increased up to 10 wt% of filler content followed by saturation at 15 wt% of filler content. It was further observed that along with fillers (Jute and Cu) incorporation, the thermal insulation was decreased monotonically up to 10 wt% of filler content and achieved a saturation at 15 wt% of filler content. A similar trend was observed with the variation of electrical conductivity and thermal insulation after incorporation of graphite within copper reinforced UP/Jute composites. Structural investigation through SEM, XRD and FTIR confirm the dispersion of fillers. An improvement of crystallinity of the matrix with fillers addition was observed from XRD analyses. The interfacial bonding between fillers and matrix was studied from FTIR pattern.

  20. Sensitivity of Arctic Permafrost Carbon in the Mackenzie River Basin: A substrate addition and incubation experiment

    NASA Astrophysics Data System (ADS)

    Hedgpeth, A.; Beilman, D.; Crow, S. E.

    2014-12-01

    Arctic soil organic matter (SOM) mineralization processes are fundamental to the functioning of high latitude soils in relation to nutrients, stability, and feedbacks to atmospheric CO2 and climate. The arctic permafrost zone covers 25% of the northern hemisphere and contains 1672Pg of soil carbon (C). 88% of this C currently resides in frozen soils that are vulnerable to environmental change. For instance, arctic growing seasons may be lengthened, resulting in an increase in plant productivity and rate of below ground labile C inputs as root exudates. Understanding controls on Arctic SOM dynamics requires recognition that labile C inputs have the potential to significantly affect mineralization of previously stable SOM, also known as 'priming effects'. We conducted a substrate addition incubation experiment to quantify and compare respiration in highly organic (42-48 %C) permafrost soils along a north-south transect in western Canada. Near surface soils (10-20 cm) were collected from permafrost peatland sites in the Mackenzie River Basin from 69.2-62.6°N. The surface soils are fairly young (Δ14C values > -140.0) and can be assumed to contain relatively reactive soil carbon. To assess whether addition of labile substrate alters SOM decomposition dynamics, 4.77-11.75 g of permafrost soil were spiked with 0.5 mg D-glucose g-1 soil and incubated at 5°C. A mass balance approach was used to determin substrate-induced respiration and preliminary results suggest a potential for positive priming in these C-rich soils. Baseline respiration rates from the three sites were similar (0.067-0.263 mg CO2 g-1 soil C) yet show some site-specific trends. The rate at which added substrate was utilized within these soils suggests that other factors besides temperature and soil C content are controlling substrate consumption and its effect on SOM decomposition. Microbial activity can be stimulated by substrate addition to such an extent that SOM turnover is enhanced, suggesting that

  1. Column displacement experiments to evaluate electrical conductivity effects on electromagnetic soil water sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bulk electrical conductivity (EC) in superactive soils has been shown to strongly influence electromagnetic sensing of permittivity. However, these effects are dependent on soil water content and temperature as well as the pore water conductivity. We carried out isothermal column displacement experi...

  2. Long term experience with semi-conductive glaze high voltage post insulators

    SciTech Connect

    Baker, A.C.; Maney, J.W.; Szilagyi, Z. )

    1990-01-01

    Insulators using semi-conductive glaze have long been known for their superior contamination performance. Early glazes for this type however were not stable and successful use of semi-conductive glazed porcelain insulators was delayed many years until tin-antimony oxide glazes were developed. Service experience of eighteen years is now available for line and station post insulators with this type of glaze. Based on this experience, the aging characteristics of tin-antimony oxide semi-conductive glazes are described and quantified. Several different applications of these insulators are also described.

  3. In situ vitrification and the effects of soil additives; A mixture experiment case study

    SciTech Connect

    Piepel, G.F.; Shade, J.W. )

    1992-01-01

    This paper presents a case study involving in situ vitrification (ISV), a process for immobilizing chemical or nuclear wastes in soil by melting-dissolving the contaminated soil into a glass block. One goal of the study was to investigate how viscosity and electrical conductivity were affected by mixing CaO and Na{sub 2}O with soil. A three-component constrained-region mixture experiment design was generated and the viscosity and electrical conductivity data collected. Several second-order mixture models were considered, and the Box-Cox transformation technique was applied to select property transformations. The fitted models were used to produce contour and component effects plots.

  4. Viscosity, electrical conductivity, and cesium volatility of ORNL (Oak Ridge National Laboratory) vitrified soils with limestone and sodium additives

    SciTech Connect

    Shade, J.W.; Piepel, G.F.

    1990-05-01

    Engineering- and pilot-scale tests of the in situ vitrification (ISV) process have been conducted for Oak Ridge National Laboratory (ORNL) to successfully demonstrate the feasibility of applying ISV to seepage trenches and pits at ORNL. These sites contain soil that overlies crushed limestone fill; therefore, the ISV process is applied to a soil-limestone mixture. Previous testing indicated that while a good retention level of {sup 137}Cs and {sup 90}Sr was achieved in the melt, it would be desirable to improve {sup 137}Cs retention to 99.99% if possible to minimize activity in the off-gas system. Previous testing was limited to one soil-limestone composition. Both Cs volatility and ISV power requirements are in part dependent on melt temperature and viscosity, which depend on melt composition. The study described in this report determined the effect of varying soil and limestone compositions, as well as the addition of a sodium flux, on melt viscosity, electrical conductivity, and Cs volatility. 10 refs., 15 figs., 9 tabs.

  5. Chemical and biological consequences of using carbon dioxide versus acid additions in ocean acidification experiments

    USGS Publications Warehouse

    Yates, Kimberly K.; DuFore, Christopher M.; Robbins, Lisa L.

    2013-01-01

    Use of different approaches for manipulating seawater chemistry during ocean acidification experiments has confounded comparison of results from various experimental studies. Some of these discrepancies have been attributed to whether addition of acid (such as hydrochloric acid, HCl) or carbon dioxide (CO2) gas has been used to adjust carbonate system parameters. Experimental simulations of carbonate system parameter scenarios for the years 1766, 2007, and 2100 were performed using the carbonate speciation program CO2SYS to demonstrate the variation in seawater chemistry that can result from use of these approaches. Results showed that carbonate system parameters were 3 percent and 8 percent lower than target values in closed-system acid additions, and 1 percent and 5 percent higher in closed-system CO2 additions for the 2007 and 2100 simulations, respectively. Open-system simulations showed that carbonate system parameters can deviate by up to 52 percent to 70 percent from target values in both acid addition and CO2 addition experiments. Results from simulations for the year 2100 were applied to empirically derived equations that relate biogenic calcification to carbonate system parameters for calcifying marine organisms including coccolithophores, corals, and foraminifera. Calculated calcification rates for coccolithophores, corals, and foraminifera differed from rates at target conditions by 0.5 percent to 2.5 percent in closed-system CO2 gas additions, from 0.8 percent to 15 percent in the closed-system acid additions, from 4.8 percent to 94 percent in open-system acid additions, and from 7 percent to 142 percent in open-system CO2 additions.

  6. An in situ generated carbon as integrated conductive additive for hierarchical negative plate of lead-acid battery

    NASA Astrophysics Data System (ADS)

    Saravanan, M.; Ganesan, M.; Ambalavanan, S.

    2014-04-01

    In this work, we report an in situ generated carbon from sugar as additive in the Negative Active Mass (NAM) which enhances the charge-discharge characteristics of the lead-acid cells. In situ formed sugar derived carbon (SDC) with leady oxide (LO) provides a conductive network and excellent protection against NAM irreversible lead sulfation. The effect of SDC and carbon black (CB) added negative plates are characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), galvanostatic charge-discharge, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), respectively. The results show that subtle changes in the addition of carbon to NAM led to subsequent changes on the performance during partial-state-of-charge (PSoC) operations in lead-acid cells. Furthermore, SDC added cells exhibit remarkable improvement in the rate capability, active material utilization, cycle performance and charge acceptance compared to that of the conventional CB added cells. The impact of SDC with LO at various synthesis conditions on the electrochemical performance of the negative plate is studied systematically.

  7. Additive Routes to Action Learning: Layering Experience Shapes Engagement of the Action Observation Network

    PubMed Central

    Kirsch, Louise P.; Cross, Emily S.

    2015-01-01

    The way in which we perceive others in action is biased by one's prior experience with an observed action. For example, we can have auditory, visual, or motor experience with actions we observe others perform. How action experience via 1, 2, or all 3 of these modalities shapes action perception remains unclear. Here, we combine pre- and post-training functional magnetic resonance imaging measures with a dance training manipulation to address how building experience (from auditory to audiovisual to audiovisual plus motor) with a complex action shapes subsequent action perception. Results indicate that layering experience across these 3 modalities activates a number of sensorimotor cortical regions associated with the action observation network (AON) in such a way that the more modalities through which one experiences an action, the greater the response is within these AON regions during action perception. Moreover, a correlation between left premotor activity and participants' scores for reproducing an action suggests that the better an observer can perform an observed action, the stronger the neural response is. The findings suggest that the number of modalities through which an observer experiences an action impacts AON activity additively, and that premotor cortical activity might serve as an index of embodiment during action observation. PMID:26209850

  8. MREIT conductivity imaging based on the local harmonic Bz algorithm: Animal experiments

    NASA Astrophysics Data System (ADS)

    Jeon, Kiwan; Lee, Chang-Ock; Woo, Eung Je; Kim, Hyung Joong; Seo, Jin Keun

    2010-04-01

    From numerous numerical and phantom experiments, MREIT conductivity imaging based on harmonic Bz algorithm shows that it could be yet another useful medical imaging modality. However, in animal experiments, the conventional harmonic Bz algorithm gives poor results near boundaries of problematic regions such as bones, lungs, and gas-filled stomach, and the subject boundary where electrodes are not attached. Since the amount of injected current is low enough for the safety for in vivo animal, the measured Bz data is defected by severe noise. In order to handle such problems, we use the recently developed local harmonic Bz algorithm to obtain conductivity images in our ROI(region of interest) without concerning the defected regions. Furthermore we adopt a denoising algorithm that preserves the ramp structure of Bz data, which informs of the location and size of anomaly. Incorporating these efficient techniques, we provide the conductivity imaging of post-mortem and in vivo animal experiments with high spatial resolution.

  9. Physical conditions for conducting radiobiological experiments in beams of accelerated particles with high linear energy transfer

    NASA Technical Reports Server (NTRS)

    Kudryashov, Y. I.; Marennyy, A. M.; Popov, V. I.; Aykhorn, K.; Ertsgreber, G.

    1974-01-01

    The design and construction of an accelerator to conduct radiobiological experiments is reported that uses aluminum filters to control the accelerated ion beam while preserving its stability, and a vacuum chamber to conduct the ion beam with the help of a collector through a lavsan exit port to the target. Depth distribution of the absorbed dose from a monodirectional ion beam is practically completely represented by the change in the energy spectrum of the biological object.

  10. An additional condition for Bell experiments for accepting local realistic theories

    NASA Astrophysics Data System (ADS)

    Nagata, Koji; Nakamura, Tadao

    2013-12-01

    We assume that one source of two uncorrelated spin-carrying particles emits them in a state, which can be described as a spin-1/2 bipartite pure uncorrelated state. We consider a Bell-Clauser-Horne-Shimony-Holt (Bell-CHSH) experiment with two-orthogonal-settings. We propose an additional condition for the state to be reproducible by the property of local realistic theories. We use the proposed measurement theory in order to construct the additional condition (Nagata and Nakamura in Int J Theor Phys 49:162, 2010). The condition is that local measurement outcome is . Otherwise, such an experiment does not allow for the existence of local realistic theories even in the situation that all Bell-CHSH inequalities hold. Also we derive new set of Bell inequalities when local measurement outcome is.

  11. Biochar-Induced Changes in Soil Hydraulic Conductivity and Dissolved Nutrient Fluxes Constrained by Laboratory Experiments

    PubMed Central

    Barnes, Rebecca T.; Gallagher, Morgan E.; Masiello, Caroline A.; Liu, Zuolin; Dugan, Brandon

    2014-01-01

    The addition of charcoal (or biochar) to soil has significant carbon sequestration and agronomic potential, making it important to determine how this potentially large anthropogenic carbon influx will alter ecosystem functions. We used column experiments to quantify how hydrologic and nutrient-retention characteristics of three soil materials differed with biochar amendment. We compared three homogeneous soil materials (sand, organic-rich topsoil, and clay-rich Hapludert) to provide a basic understanding of biochar-soil-water interactions. On average, biochar amendment decreased saturated hydraulic conductivity (K) by 92% in sand and 67% in organic soil, but increased K by 328% in clay-rich soil. The change in K for sand was not predicted by the accompanying physical changes to the soil mixture; the sand-biochar mixture was less dense and more porous than sand without biochar. We propose two hydrologic pathways that are potential drivers for this behavior: one through the interstitial biochar-sand space and a second through pores within the biochar grains themselves. This second pathway adds to the porosity of the soil mixture; however, it likely does not add to the effective soil K due to its tortuosity and smaller pore size. Therefore, the addition of biochar can increase or decrease soil drainage, and suggests that any potential improvement of water delivery to plants is dependent on soil type, biochar amendment rate, and biochar properties. Changes in dissolved carbon (C) and nitrogen (N) fluxes also differed; with biochar increasing the C flux from organic-poor sand, decreasing it from organic-rich soils, and retaining small amounts of soil-derived N. The aromaticity of C lost from sand and clay increased, suggesting lost C was biochar-derived; though the loss accounts for only 0.05% of added biochar-C. Thus, the direction and magnitude of hydraulic, C, and N changes associated with biochar amendments are soil type (composition and particle size) dependent

  12. Biochar-induced changes in soil hydraulic conductivity and dissolved nutrient fluxes constrained by laboratory experiments.

    PubMed

    Barnes, Rebecca T; Gallagher, Morgan E; Masiello, Caroline A; Liu, Zuolin; Dugan, Brandon

    2014-01-01

    The addition of charcoal (or biochar) to soil has significant carbon sequestration and agronomic potential, making it important to determine how this potentially large anthropogenic carbon influx will alter ecosystem functions. We used column experiments to quantify how hydrologic and nutrient-retention characteristics of three soil materials differed with biochar amendment. We compared three homogeneous soil materials (sand, organic-rich topsoil, and clay-rich Hapludert) to provide a basic understanding of biochar-soil-water interactions. On average, biochar amendment decreased saturated hydraulic conductivity (K) by 92% in sand and 67% in organic soil, but increased K by 328% in clay-rich soil. The change in K for sand was not predicted by the accompanying physical changes to the soil mixture; the sand-biochar mixture was less dense and more porous than sand without biochar. We propose two hydrologic pathways that are potential drivers for this behavior: one through the interstitial biochar-sand space and a second through pores within the biochar grains themselves. This second pathway adds to the porosity of the soil mixture; however, it likely does not add to the effective soil K due to its tortuosity and smaller pore size. Therefore, the addition of biochar can increase or decrease soil drainage, and suggests that any potential improvement of water delivery to plants is dependent on soil type, biochar amendment rate, and biochar properties. Changes in dissolved carbon (C) and nitrogen (N) fluxes also differed; with biochar increasing the C flux from organic-poor sand, decreasing it from organic-rich soils, and retaining small amounts of soil-derived N. The aromaticity of C lost from sand and clay increased, suggesting lost C was biochar-derived; though the loss accounts for only 0.05% of added biochar-C. Thus, the direction and magnitude of hydraulic, C, and N changes associated with biochar amendments are soil type (composition and particle size) dependent

  13. NASA's Rodent Research Project: Validation of Capabilities for Conducting Long Duration Experiments in Space

    NASA Technical Reports Server (NTRS)

    Choi, Sungshin Y.; Cole, Nicolas; Reyes, America; Lai, San-Huei; Klotz, Rebecca; Beegle, Janet E.; Wigley, Cecilia L.; Pletcher, David; Globus, Ruth K.

    2015-01-01

    Research using rodents is an essential tool for advancing biomedical research on Earth and in space. Prior rodent experiments on the Shuttle were limited by the short flight duration. The International Space Station (ISS) provides a new platform for conducting rodent experiments under long duration conditions. Rodent Research (RR)-1 was conducted to validate flight hardware, operations, and science capabilities that were developed at the NASA Ames Research Center. Twenty C57BL6J adult female mice were launched on Sept 21, 2014 in a Dragon Capsule (SpaceX-4), then transferred to the ISS for a total time of 21-22 days (10 commercial mice) or 37 days (10 validation mice). Tissues collected on-orbit were either rapidly frozen or preserved in RNAlater at -80C (n2group) until their return to Earth. Remaining carcasses on-orbit were rapidly frozen for dissection post-flight. The three controls groups at Kennedy Space Center consisted of: Basal mice euthanized at the time of launch, Vivarium controls housed in standard cages, and Ground Controls (GC) housed in flight hardware within an environmental chamber. Upon return to Earth, there were no differences in body weights between Flight (FLT) and GC at the end of the 37 days in space. Liver enzyme activity levels of FLT mice and all control mice were similar in magnitude to those of the samples that were processed under optimal conditions in the laboratory. Liver samples dissected on-orbit yielded high quality RNA (RIN8.99+-0.59, n7). Liver samples dissected post-flight from the intact, frozen FLT carcasses yielded RIN of 7.27 +- 0.52 (n6). Additionally, wet weights of various tissues were measured. Adrenal glands and spleen showed no significant differences in FLT compared to GC although thymus and livers weights were significantly greater in FLT compared to GC. Over 3,000 tissue aliquots collected post-flight from the four groups of mice were deposited into the Ames Life Science Data Archives for future Biospecimen

  14. Effect of addition of Ag nano powder on mechanical properties of epoxy/polyaminoamide adduct coatings filled with conducting polymer

    SciTech Connect

    Samad, Ubair Abdus; Khan, Rawaiz; Alam, Mohammad Asif; Al-Othman, Othman Y.; Al-Zahrani, Saeed M.

    2015-05-22

    In this study the effect of Ag Nano powder on mechanical properties of epoxy coatings filled with optimized ratio of conducting polymers (Polyaniline and Polyppyrole) was evaluated. Bisphenol A diglycidyl ether epoxy resin (DGEBA) along with polyaminoamide adduct (ARADUR 3282-1 BD) is used as curing agent under optimized stoichiometry values. Curing is performed at room temperature with different percentages of Nano filler. Glass and steel panels were used as coating substrate. Bird applicator was used to coat the samples in order to obtain thin film with wet film thickness (WFT) of about 70-90 µm. The samples were kept in dust free environment for about 7 days at room temperature for complete curing. The coated steel panels were used to evaluate the mechanical properties of coating such as hardness, scratch and impact tests whereas coated glass panels were used for measuring pendulum hardness of the coatings. To check the dispersion and morphology of Nano filler in epoxy matrix scanning electron microscopy (SEM) was used in addition Nano indentation was also performed to observe the effect of Nano filler on modulus of elasticity and hardness at Nano scale.

  15. Effect of addition of Ag nano powder on mechanical properties of epoxy/polyaminoamide adduct coatings filled with conducting polymer

    NASA Astrophysics Data System (ADS)

    Samad, Ubair Abdus; Khan, Rawaiz; Alam, Mohammad Asif; Al-Othman, Othman Y.; Al-Zahrani, Saeed M.

    2015-05-01

    In this study the effect of Ag Nano powder on mechanical properties of epoxy coatings filled with optimized ratio of conducting polymers (Polyaniline and Polyppyrole) was evaluated. Bisphenol A diglycidyl ether epoxy resin (DGEBA) along with polyaminoamide adduct (ARADUR 3282-1 BD) is used as curing agent under optimized stoichiometry values. Curing is performed at room temperature with different percentages of Nano filler. Glass and steel panels were used as coating substrate. Bird applicator was used to coat the samples in order to obtain thin film with wet film thickness (WFT) of about 70-90 µm. The samples were kept in dust free environment for about 7 days at room temperature for complete curing. The coated steel panels were used to evaluate the mechanical properties of coating such as hardness, scratch and impact tests whereas coated glass panels were used for measuring pendulum hardness of the coatings. To check the dispersion and morphology of Nano filler in epoxy matrix scanning electron microscopy (SEM) was used in addition Nano indentation was also performed to observe the effect of Nano filler on modulus of elasticity and hardness at Nano scale.

  16. Technical Project Plan for The Enhanced Thermal Conductivity of Oxide Fuels Through the Addition of High Thermal Conductivity Fibers and Microstructural Engineering

    SciTech Connect

    Hollenbach, Daniel F; Ott, Larry J; Besmann, Theodore M; Armstrong, Beth L; Wereszczak, Andrew A; Lin, Hua-Tay; Ellis, Ronald James; Becher, Paul F; Jubin, Robert Thomas; Voit, Stewart L

    2010-09-01

    The commercial nuclear power industry is investing heavily in advanced fuels that can produce higher power levels with a higher safety margin and be produced at low cost. Although chemically stable and inexpensive to manufacture, the in-core performance of UO{sub 2} fuel is limited by its low thermal conductivity. There will be enormous financial benefits to any utility that can exploit a new type of fuel that is chemically stable, has a high thermal conductivity, and is inexpensive to manufacture. At reactor operating temperatures, UO{sub 2} has a very low thermal conductivity (<5 W/m {center_dot}K), which decreases with temperature and fuel burnup. This low thermal conductivity limits the rate at which energy can be removed from the fuel, thus limiting the total integrated reactor power. If the fuel thermal conductivity could be increased, nuclear reactors would be able to operate at higher powers and larger safety margins thus decreasing the overall cost of electricity by increasing the power output from existing reactors and decreasing the number of new electrical generating plants needed to meet base load demand. The objective of the work defined herein is to produce an advanced nuclear fuel based on the current UO{sub 2} fuel with superior thermal conductivity and structural integrity that is suitable for current and future nuclear reactors, using the existing fuel fabrication infrastructure with minimal modifications. There are two separate components to the research: (1) Enhanced Thermal Conductivity (ETC) - adding high conductivity fibers to the UO{sub 2} prior to sintering, which act as conduits for moving the heat energy generated within the pellet to the outer surface, (2) Microstructural Engineering (ME) - adding second phase particulates to UO{sub 2} bodies to retard grain growth and to increase thermal conductivity, as well as improve fracture and creep resistance. Different groups will perform the laboratory work for each of these research

  17. Conducting polymer-skinned electroactive materials of lithium-ion batteries: ready for monocomponent electrodes without additional binders and conductive agents.

    PubMed

    Kim, Ju-Myung; Park, Han-Saem; Park, Jang-Hoon; Kim, Tae-Hee; Song, Hyun-Kon; Lee, Sang-Young

    2014-08-13

    Rapid growth of mobile and even wearable electronics is in pursuit of high-energy-density lithium-ion batteries. One simple and facile way to achieve this goal is the elimination of nonelectroactive components of electrodes such as binders and conductive agents. Here, we present a new concept of monocomponent electrodes comprising solely electroactive materials that are wrapped with an insignificant amount (less than 0.4 wt %) of conducting polymer (PEDOT:PSS or poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate)). The PEDOT:PSS as an ultraskinny surface layer on electroactive materials (LiCoO2 (LCO) powders are chosen as a model system to explore feasibility of this new concept) successfully acts as a kind of binder as well as mixed (both electrically and ionically) conductive film, playing a key role in enabling the monocomponent electrode. The electric conductivity of the monocomponent LCO cathode is controlled by simply varying the PSS content and also the structural conformation (benzoid-favoring coil structure and quinoid-favoring linear or extended coil structure) of PEDOT in the PEDOT:PSS skin. Notably, a substantial increase in the mass-loading density of the LCO cathode is realized with the PEDOT:PSS skin without sacrificing electronic/ionic transport pathways. We envisage that the PEDOT:PSS-skinned electrode strategy opens a scalable and versatile route for making practically meaningful binder-/conductive agent-free (monocomponent) electrodes. PMID:24988178

  18. Characterization of stony soils' hydraulic conductivity using laboratory and numerical experiments

    NASA Astrophysics Data System (ADS)

    Beckers, Eléonore; Pichault, Mathieu; Pansak, Wanwisa; Degré, Aurore; Garré, Sarah

    2016-08-01

    Determining soil hydraulic properties is of major concern in various fields of study. Although stony soils are widespread across the globe, most studies deal with gravel-free soils, so that the literature describing the impact of stones on the hydraulic conductivity of a soil is still rather scarce. Most frequently, models characterizing the saturated hydraulic conductivity of stony soils assume that the only effect of rock fragments is to reduce the volume available for water flow, and therefore they predict a decrease in hydraulic conductivity with an increasing stoniness. The objective of this study is to assess the effect of rock fragments on the saturated and unsaturated hydraulic conductivity. This was done by means of laboratory experiments and numerical simulations involving different amounts and types of coarse fragments. We compared our results with values predicted by the aforementioned predictive models. Our study suggests that it might be ill-founded to consider that stones only reduce the volume available for water flow. We pointed out several factors of the saturated hydraulic conductivity of stony soils that are not considered by these models. On the one hand, the shape and the size of inclusions may substantially affect the hydraulic conductivity. On the other hand, laboratory experiments show that an increasing stone content can counteract and even overcome the effect of a reduced volume in some cases: we observed an increase in saturated hydraulic conductivity with volume of inclusions. These differences are mainly important near to saturation. However, comparison of results from predictive models and our experiments in unsaturated conditions shows that models and data agree on a decrease in hydraulic conductivity with stone content, even though the experimental conditions did not allow testing for stone contents higher than 20 %.

  19. Conducting Action Research in Kenyan Primary Schools: A Narrative of Lived Experiences

    ERIC Educational Resources Information Center

    Otienoh, Ruth

    2015-01-01

    This paper is a narrative of my personal experiences of conducting action research in Kenyan primary schools. It highlights the opportunities, successes, challenges and dilemmas I encountered during the process: from the school hunting period, to the carrying out of the actual research in two schools, with four teachers. This study reveals that…

  20. Conducting Design Experiments to Support Teachers' Learning: A Reflection from the Field

    ERIC Educational Resources Information Center

    Cobb, Paul; Zhao, Qing; Dean, Chrystal

    2009-01-01

    This article focuses on 3 conceptual challenges that we sought to address while conducting a design experiment in which we supported the learning of a group of middle school mathematics teachers. These challenges involved (a) situating teachers' activity in the institutional setting of the schools and district in which they worked, (b) developing…

  1. Using Conductivity Measurements to Determine the Identities and Concentrations of Unknown Acids: An Inquiry Laboratory Experiment

    ERIC Educational Resources Information Center

    Smith, K. Christopher; Garza, Ariana

    2015-01-01

    This paper describes a student designed experiment using titrations involving conductivity measurements to identify unknown acids as being either HCl or H[subscript 2]SO[subscript 4], and to determine the concentrations of the acids, thereby improving the utility of standard acid-base titrations. Using an inquiry context, students gain experience…

  2. Estimating the hydraulic conductivity of slowly permeable and swelling materials from single-ring experiments

    NASA Astrophysics Data System (ADS)

    GéRard-Marchant, P.; Angulo-Jaramillo, R.; Haverkamp, R.; Vauclin, M.; Groenevelt, P.; Elrick, D. E.

    1997-06-01

    The in situ determination of the field-saturated hydraulic conductivity of low-permeability porous materials is a major concern for both geotechnics and soil physics with regards to environmental protection or water resources management. Recent early-time single-ring infiltration experiments, involving sequential constant head and falling head conditions, allow its efficient estimation. Nevertheless, the theory on which the interpretation was based was still strictly valid to nondeformable soils and implicity relied on a particular form of the hydraulic conductivity-soil water pressure head relationship. This theory is now extended to deformable materials, without any restrictive hypothesis. A new concept, bulk sorptivity, which characterizes the solid phase movement, is introduced. Field experiments, conducted on two liners of swelling and slowly permeable materials, revealed that neglecting the soil deformation induces an underestimation of the actual coefficient of permeability of the soil.

  3. psiTurk: An open-source framework for conducting replicable behavioral experiments online.

    PubMed

    Gureckis, Todd M; Martin, Jay; McDonnell, John; Rich, Alexander S; Markant, Doug; Coenen, Anna; Halpern, David; Hamrick, Jessica B; Chan, Patricia

    2016-09-01

    Online data collection has begun to revolutionize the behavioral sciences. However, conducting carefully controlled behavioral experiments online introduces a number of new of technical and scientific challenges. The project described in this paper, psiTurk, is an open-source platform which helps researchers develop experiment designs which can be conducted over the Internet. The tool primarily interfaces with Amazon's Mechanical Turk, a popular crowd-sourcing labor market. This paper describes the basic architecture of the system and introduces new users to the overall goals. psiTurk aims to reduce the technical hurdles for researchers developing online experiments while improving the transparency and collaborative nature of the behavioral sciences. PMID:26428910

  4. Spinel dissolution via addition of glass forming chemicals. Results of preliminary experiments

    SciTech Connect

    Fox, K. M.; Johnson, F. C.

    2015-11-01

    Increased loading of high level waste in glass can lead to crystallization within the glass. Some crystalline species, such as spinel, have no practical impact on the chemical durability of the glass, and therefore may be acceptable from both a processing and a product performance standpoint. In order to operate a melter with a controlled amount of crystallization, options must be developed for remediating an unacceptable accumulation of crystals. This report describes preliminary experiments designed to evaluate the ability to dissolve spinel crystals in simulated waste glass melts via the addition of glass forming chemicals (GFCs).

  5. Interpretation of injection-withdrawal tracer experiments conducted between two wells in a large single fracture.

    PubMed

    Novakowski, K S; Bickerton, G; Lapcevic, P

    2004-09-01

    Tracer experiments conducted using a flow field established by injecting water into one borehole and withdrawing water from another are often used to establish connections and investigate dispersion in fractured rock. As a result of uncertainty in the uniqueness of existing models used for interpretation, this method has not been widely used to investigate more general transport processes including matrix diffusion or advective solute exchange between mobile and immobile zones of fluid. To explore the utility of the injection-withdrawal method as a general investigative tool and with the intent to resolve the transport processes in a discrete fracture, two tracer experiments were conducted using the injection-withdrawal configuration. The experiments were conducted in a fracture which has a large aperture (>500 microm) and horizontally pervades a dolostone formation. One experiment was conducted in the direction of the hydraulic gradient and the other in the direction opposite to the natural gradient. Two tracers having significantly different values of the free-water diffusion coefficient were used. To interpret the experiments, a hybrid numerical-analytical model was developed which accounts for the arcuate shape of the flow field, advection-dispersion in the fracture, diffusion into the matrix adjacent to the fracture, and the presence of natural flow in the fracture. The model was verified by comparison to a fully analytical solution and to a well-known finite-element model. Interpretation of the tracer experiments showed that when only one tracer, advection-dispersion, and matrix diffusion are considered, non-unique results were obtained. However, by using multiple tracers and by accounting for the presence of natural flow in the fracture, unique interpretations were obtained in which a single value of matrix porosity was estimated from the results of both experiments. The estimate of porosity agrees well with independent measurements of porosity obtained from

  6. Combustion Module-2 Preparations Completed for SPACEHAB Mission Including the Addition of a New Major Experiment

    NASA Technical Reports Server (NTRS)

    Over, Ann P.

    2001-01-01

    The Combustion Module-1 (CM-1) was a large, state-of-the-art space shuttle Spacelab facility that was designed, built, and operated on STS-83 and STS-94 by a team from the NASA Glenn Research Center composed of civil servants and local support contractors (Analex and Zin Technologies). CM-1 accomplished the incredible task of providing a safe environment to support flammable and toxic gases while providing a suite of diagnostics for science measurements more extensive than any prior shuttle experiment (or anything since). Finally, CM-1 proved that multiple science investigations can be accommodated in one facility, a crucial step for Glenn's Fluids and Combustion Facility developed for the International Space Station. However, the story does not end with CM-1. In 1998, CM-2 was authorized to take the CM-1 accomplishments a big step further by completing three major steps: Converting the entire experiment to operate in a SPACEHAB module. Conducting an extensive hardware refurbishment and upgrading diagnostics (e.g., cameras, gas chromatograph, and numerous sensors). Adding a new, completely different combustion experiment.

  7. Effect of Li{sub 2}SO{sub 4} addition on structure and ionic conductivity of lithium borosilicotitanate glasses

    SciTech Connect

    Satpute, N. S.; Deshpande, A. V.

    2014-04-24

    Lithium borosilicotitanate glasses containing Li{sub 2}SO{sub 4} were prepared by melt quenching technique. Electrical conductivity, density, molar volume and glass transition temperature T{sub g} for all the glass samples were measured. IR spectroscopy was used for structural studies of these glasses in the range from 400 to 2000 cm{sub −1}. The conductivity of the Li{sub 2}SO{sub 4} containing glasses was found to be half an order higher than the base glass. The electrical conductivity was interpreted from the point of view of glass structure which suggests that an enhancement in conductivity is due to the incorporation of Li{sub 2}SO{sub 4} in the macromolecular network. The molar volume and glass transition temperature T{sub g} results are found to be in good correlation with conductivity results.

  8. Computational/experimental basis for conducting alkane droplet combustion experiments on space-based-platforms

    NASA Technical Reports Server (NTRS)

    Choi, Mun Y.; Cho, Seog Y.; Dryer, Frederick L.; Haggard, John B., Jr.

    1992-01-01

    An analysis is conducted of the requirement for the conduct of spherically symmetric droplet-combustion experiments on space platforms, on the basis of a novel time-dependent computational droplet combustion model that allows the time- and temperature-dependent transport characteristics to be incorporated. While at low oxygen indices the droplet burning extinction becomes a strong function of oxygen index, it becomes a weaker function at higher oxygen index values. The oxygen index that separates these two ranges are dependent on the diluent, being higher for He and lower for N.

  9. STS-47 Payload Specialist Mohri conducts visual stability experiment in SLJ

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-47 Payload Specialist Mamoru Mohri, using the light impulse stimulation experiment hardware, conducts Comparative Measurement of Visual Stability in Earth and Cosmic Space (VISUAL STABILITY). The hardware is set up in the forward section of the Spacelab Japan (SLJ) science module aboard the Earth-orbiting Endeavour, Orbiter Vehicle (OV) 105. The experiment will investigate the lack of eye, head, and body coordination as a possible contributor to space adaptation syndrome (SAS). Electrodes attached to Mohri record his eye movements and neck tension as he tracks a flickering light while he is at a 45-degree angle. Mohri represents Japan's National Space Development Agency (NASDA).

  10. Video of Miscible Fluid Experiment Conducted on NASA Low Gravity Airplane

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This is a video of dyed water being injected into glycerin in a 2.2 centimeter (cm) diameter test tube. The experiment was conducted on the KC-135 aircraft, a NASA plane that creates microgravity and 2g conditions as it maneuvers through multiple parabolas. The water is less dense and so it rises to the top of the glycerin. The goal of the experiment was to determine if a blob of a miscible fluid would spontaneously become spherical in a microgravity environment.

  11. Additional experiments relative to the shelf life of Li(Si)/FeS2 thermal batteries

    NASA Astrophysics Data System (ADS)

    Searcy, J. Q.; Armijo, J. R.

    1985-02-01

    A continuing effort to develop a new thermal battery technology based on the Li(Si)/FeS2 electrochemical couple is reported. The results relate to the long shelf life requirement for thermal batteries designed by Sandia, and include topics relevant to leakage through the hermetic seal and accelerated aging experiments with materials new to the technology. Conclusions relevant to leakage through the hermetic seal are that the maximum leak rate must not exceed 1.8 x 10(-7) w, where w is the grams of Li(Si) contained by a battery, and that a bomb type leak test can be designed that is adequate for most Li(Si)/FeS2 batteries. Conclusions relevant to long term compatibility of new materials include the following: nickel is not compatible with the iron disulfide in the cathode; the CaSi2 additive used to suppress the initial voltage transient does not react or degrade during accelerated aging experiments, but the use of that material can lead to an increase in the variability of the activated lives, especially for long life batteries; Grafoil current collectors used with the cathode do not degrade in accelerated aging experiments.

  12. Enhanced ionic conductivity of Ce0.8Sm0.2O2-δ by Sr addition

    NASA Astrophysics Data System (ADS)

    Gao, Zhan; Liu, Xingmin; Bergman, Bill; Zhao, Zhe

    2012-06-01

    Sm and Sr co-doped ceria-based electrolyte with compositions of Ce0.8(Sm1-xSrx)0.2O2-δ (x = 0, 0.3, 0.5, 0.7) are synthesized and investigated with the aim of improving the electrical properties of Ce0.8Sm0.2O2-δ. X-ray diffraction (XRD) and electron microscope (SEM and TEM) techniques are employed to characterize the microstructure of powders and sintered pellets. The ionic conductivity has been examined by the A.C. impedance spectroscopy in air. The Ce0.8(Sm0.7Sr0.3)0.2O2-δ exhibits the highest bulk conductivity among the series, which can be mainly ascribed to the increase of oxygen vacancy concentration. The specific grain-boundary conductivities are observed to increase with the Sr doping content up to x = 0.5. Further increase in Sr concentration will lead to reduced specific grain-boundary conductivities. The total conductivities of all Sm and Sr co-doped ceria are higher than that of Ce0.8Sm0.2O1.9. The results indicate that Sr co-doping opens a new avenue to improve ionic conductivity in Ce0.8Sm0.2O1.9.

  13. Portable conduction velocity experiments using earthworms for the college and high school neuroscience teaching laboratory.

    PubMed

    Shannon, Kyle M; Gage, Gregory J; Jankovic, Aleksandra; Wilson, W Jeffrey; Marzullo, Timothy C

    2014-03-01

    The earthworm is ideal for studying action potential conduction velocity in a classroom setting, as its simple linear anatomy allows easy axon length measurements and the worm's sparse coding allows single action potentials to be easily identified. The earthworm has two giant fiber systems (lateral and medial) with different conduction velocities that can be easily measured by manipulating electrode placement and the tactile stimulus. Here, we present a portable and robust experimental setup that allows students to perform conduction velocity measurements within a 30-min to 1-h laboratory session. Our improvement over this well-known preparation is the combination of behaviorally relevant tactile stimuli (avoiding electrical stimulation) with the invention of minimal, low-cost, and portable equipment. We tested these experiments during workshops in both a high school and college classroom environment and found positive learning outcomes when we compared pre- and posttests taken by the students. PMID:24585472

  14. Electrical conductivity and permeability of partially molten mantle rocks: results from digital rock physics experiments

    NASA Astrophysics Data System (ADS)

    Miller, K.; Montesi, L.; Zhu, W.

    2014-12-01

    Estimates of overall melt content beneath mid-ocean ridges inferred from magnetotelluric tomography (MT) studies vary widely between 1 and 10 vol. %. Much of this variation may arise from a lack of understanding about how melt geometry influences the bulk electrical conductivity of partially molten mantle rock, especially at low melt fraction. We present results from experiments in which we numerically calculate the electrical conductivity and permeability using high-resolution, three-dimensional melt geometries of olivine-basalt systems obtained via synchrotron X-ray microtomography (SXμT). Starting materials consist of San Carlos olivine and Fo90 basalt mixed in various proportions to achieve nominal melt fraction of 0.02 to 0.20 when melted. Samples were prepared by isostatically pressing samples at 1.5GPa and 1350°C for a minimum of 1 week (Zhu et al., 2011; Science) and then quenched, turning the melt to basaltic glass. Samples were imaged using SXμT at the Advanced Photon Source at Argonne National Labs to obtain three-dimensional, 700 nm-per-pixel digital reconstructions. Grayscale data was segmented using Avizo® software (Miller et al., 2014; EPSL), and binary images were used as computational domains in numerical experiments to determine bulk electrical conductivity and permeability. Numerical experiments were carried out on several statistically representative subvolumes per sample using finite difference techniques. Olivine and melt are treated as conductive and insulative phases, respectively. To calculate conductivity, Laplace's equation is solved for the electric potential, assuming zero electric flux across phase boundaries. Ohm's Law yields the bulk conductivity of the sample. To calculate permeability, Stokes' equations are solved using the artificial compressibility method on a staggered grid. Darcy's law then gives the permeability of the subvolume. We fit permeability and electrical conductivity values to power laws in order to establish

  15. Copper Conductivity Model Development and Validation Using Flyer Plate Experiments on the Z-machine

    NASA Astrophysics Data System (ADS)

    Riford, L.; Lemke, R. W.; Cochrane, K.

    2015-11-01

    Magnetically accelerated flyer plate experiments done on Sandia's Z-machine provide insight into a multitude of materials problems at high energies and densities including conductivity model development and validation. In an experiment with ten Cu flyer plates of thicknesses 500-1000 μm, VISAR measurements exhibit a characteristic jump in the velocity correlated with magnetic field burn-through and the expansion of melted material at the free surface. The experiment is modeled using Sandia's shock and multiphysics MHD code ALEGRA. Simulated free surface velocities are within 1% of the measured data early in time, but divergence occurs at the feature, where the simulation indicates a slower burn through time. The cause was found to be in the Cu conductivity model's compressed regime. The model was improved by lowering the conductivity in the region 12.5-16 g/cc and 350-16000 K with a novel parameter based optimization method using the velocity feature as a figure of merit. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U. S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  16. Optimization of Acetylene Black Conductive Additive andPolyvinylidene Difluoride Composition for High Power RechargeableLithium-Ion Cells

    SciTech Connect

    Liu, G.; Zheng, H.; Battaglia, V.S.; Simens, A.S.; Minor, A.M.; Song, X.

    2007-07-01

    Fundamental electrochemical methods were applied to study the effect of the acetylene black (AB) and the polyvinylidene difluoride (PVDF) polymer binder on the performance of high-power designed rechargeable lithium ion cells. A systematic study of the AB/PVDF long-range electronic conductivity at different weight ratios is performed using four-probe direct current tests and the results reported. There is a wide range of AB/PVDF ratios that satisfy the long-range electronic conductivity requirement of the lithium-ion cathode electrode; however, a significant cell power performance improvement is observed at small AB/PVDF composition ratios that are far from the long-range conductivity optimum of 1 to 1.25. Electrochemical impedance spectroscopy (EIS) tests indicate that the interfacial impedance decreases significantly with increase in binder content. The hybrid power pulse characterization results agree with the EIS tests and also show improvement for cells with a high PVDF content. The AB to PVDF composition plays a significant role in the interfacial resistance. We believe the higher binder contents lead to a more cohesive conductive carbon particle network that results in better overall all local electronic conductivity on the active material surface and hence reduced charge transfer impedance.

  17. Spaceflight hardware for conducting plant growth experiments in space: the early years 1960-2000

    NASA Technical Reports Server (NTRS)

    Porterfield, D. M.; Neichitailo, G. S.; Mashinski, A. L.; Musgrave, M. E.

    2003-01-01

    The best strategy for supporting long-duration space missions is believed to be bioregenerative life support systems (BLSS). An integral part of a BLSS is a chamber supporting the growth of higher plants that would provide food, water, and atmosphere regeneration for the human crew. Such a chamber will have to be a complete plant growth system, capable of providing lighting, water, and nutrients to plants in microgravity. Other capabilities include temperature, humidity, and atmospheric gas composition controls. Many spaceflight experiments to date have utilized incomplete growth systems (typically having a hydration system but lacking lighting) to study tropic and metabolic changes in germinating seedlings and young plants. American, European, and Russian scientists have also developed a number of small complete plant growth systems for use in spaceflight research. Currently we are entering a new era of experimentation and hardware development as a result of long-term spaceflight opportunities available on the International Space Station. This is already impacting development of plant growth hardware. To take full advantage of these new opportunities and construct innovative systems, we must understand the results of past spaceflight experiments and the basic capabilities of the diverse plant growth systems that were used to conduct these experiments. The objective of this paper is to describe the most influential pieces of plant growth hardware that have been used for the purpose of conducting scientific experiments during the first 40 years of research. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

  18. Sea experiments of the Underway Conductivity-Temperature-Depth prototype made in China

    NASA Astrophysics Data System (ADS)

    Song, Xiangzhou; Li, Hui; Lin, Xiaopei; Chen, Xueen; Guo, Xinshun; Tian, Jiwei

    2009-12-01

    A new instrument for upper ocean survey, namely the UCTD (Underway Conductivity-Temperature-Depth), which combines some of the advantages of other underway instruments, is introduced in this paper. The Introduction section presents a description of the construction and function of the UCTD, and the experiments conducted in the South China Sea on board the R/V Dong Fang Hong 2 in July 2007 and August 2008. The UCTD system, with pressure and temperature sensors in the probe, is conveniently portable, cost-effective and environment-friendly. It is hopefully suitable for future cruises. An intercomparison based on regressing with the experiment temperature data from both SeaBird plus911 CTD and the UCTD showed that the standard deviation is 0.88°C and the correlation coefficient is 0.96, achieving the goals set for the current oceanography uses. In the hydrodynamic experiments, the descending velocities and depths were calculated for different ship speeds. A pulling test was designed with a tensiometer to measure the magnitude of the pull. The maximal tension of the line was found to be 66.2 kg, which is far lower than the bearing limit of the Hollow Spectra line. Finally, some improvement suggestions are put forward for future experiments and production.

  19. FEANICS: A Multi-User Facility For Conducting Solid Fuel Combustion Experiments On ISS

    NASA Technical Reports Server (NTRS)

    Frate, David T.; Tofil, Todd A.

    2001-01-01

    The Destiny Module on the International Space Station (ISS) will soon be home for the Fluids and Combustion Facility's (FCF) Combustion Integrated Rack (CIR), which is being developed at the NASA Glenn Research Center in Cleveland, Ohio. The CIR will be the platform for future microgravity combustion experiments. A multi-user mini-facility called FEANICS (Flow Enclosure Accommodating Novel Investigations in Combustion of Solids) will also be built at NASA Glenn. This mini-facility will be the primary means for conducting solid fuel combustion experiments in the CIR on ISS. The main focus of many of these solid combustion experiments will be to conduct basic and applied scientific investigations in fire-safety to support NASA's Bioastronautics Initiative. The FEANICS project team will work in conjunction with the CIR project team to develop upgradeable and reusable hardware to meet the science requirements of current and future investigators. Currently, there are six experiments that are candidates to use the FEANICS mini-facility. This paper will describe the capabilities of this mini-facility and the type of solid combustion testing and diagnostics that can be performed.

  20. Sand box experiments with bioclogging of porous media: Hydraulic conductivity reductions

    NASA Astrophysics Data System (ADS)

    Seifert, Dorte; Engesgaard, Peter

    2012-08-01

    Tracer experiments during clogging and de-clogging experiments in a 2D sand box were via an image analysis used to establish a data set on the relation between changes in hydraulic conductivity (K) and relative porosity (β). Clogging appears to create a finger-like tracer transport, which could be caused by an initial heterogeneous distribution of biomass in the sand box. De-clogging occurs at a slower rate possibly due to the presence of inert biomass that is not affected by the starvation conditions by sudden removal of the substrate source. The tracer front was observed to get disturbed closer and closer to the substrate source during the experiments suggesting that the zone of clogging moved upstream. Three clogging models, K(β), from the literature were tested for their ability to describe the temporal changes in clogging at the scale of the sand box; the model of Clement et al. (1996) that makes no assumption on biomass distribution, the plug formation model of Thullner et al. (2002a), and the biofilm-plug formation model of Vandevivere (1995). The plug formation and biofilm-plug formation models both match the observed changes between the hydraulic conductivity of the sand box and the relative porosity. Unfortunately our experiments did not reach low relative porosities where the two models predict different behaviors. The model by Clement et al. (1996) underestimates clogging.

  1. Cool in the kitchen: Radiation, conduction, and the Newton ``hot block'' experiment

    NASA Astrophysics Data System (ADS)

    Silverman, Mark P.; Silverman, Christopher R.

    2000-02-01

    Despite frequent reference to Newton's law of cooling in physics and math books, the paper in which Newton reported this law is quite obscure and rarely cited. We have managed to acquire a copy of this paper and discuss the interesting experiment that Newton did in his kitchen. Surprisingly, the paper contains no procedural details or data of any experiments measuring the rate at which a hot object cools. We have performed our own kitchen experiments to investigate the cooling of (a) the burner of an electric range and (b) a block of Styrofoam. Newton's law provides a poor model for both systems, whose th! ! ermal energy loss we can much better understand by examining closely the effects of radiation and conduction.

  2. Responses of estuarine nematodes to an increase in nutrient supply: an in situ continuous addition experiment.

    PubMed

    Ferreira, R C; Nascimento-Junior, A B; Santos, P J P; Botter-Carvalho, M L; Pinto, T K

    2015-01-15

    An experiment was carried out on an estuarine mudflat to assess impacts of inorganic nutrients used to fertilize sugar-cane fields on the surrounding aquatic ecosystem, through changes in the nematode community structure. During 118 days, nine quadrats each 4m(2) were sampled six times after the beginning of fertilizer addition. The fertilizer was introduced weekly in six areas, at two different concentrations (low and high doses), and three areas were used as control. The introduction of nutrients modified key nematode community descriptors. In general, the nematodes were negatively affected over the study period. However, Comesa, Metachromadora, Metalinhomoeus, Spirinia and Terschellingia were considered tolerant, and other genera showed different degrees of sensitivity. Nutrient input also affect the availability and quality of food, changing the nematode trophic structure. The use of inorganic fertilizer should be evaluated with care because of the potential for damage to biological communities of coastal aquatic systems. PMID:25499965

  3. Loophole-free Bell test using electron spins in diamond: second experiment and additional analysis.

    PubMed

    Hensen, B; Kalb, N; Blok, M S; Dréau, A E; Reiserer, A; Vermeulen, R F L; Schouten, R N; Markham, M; Twitchen, D J; Goodenough, K; Elkouss, D; Wehner, S; Taminiau, T H; Hanson, R

    2016-01-01

    The recently reported violation of a Bell inequality using entangled electronic spins in diamonds (Hensen et al., Nature 526, 682-686) provided the first loophole-free evidence against local-realist theories of nature. Here we report on data from a second Bell experiment using the same experimental setup with minor modifications. We find a violation of the CHSH-Bell inequality of 2.35 ± 0.18, in agreement with the first run, yielding an overall value of S = 2.38 ± 0.14. We calculate the resulting P-values of the second experiment and of the combined Bell tests. We provide an additional analysis of the distribution of settings choices recorded during the two tests, finding that the observed distributions are consistent with uniform settings for both tests. Finally, we analytically study the effect of particular models of random number generator (RNG) imperfection on our hypothesis test. We find that the winning probability per trial in the CHSH game can be bounded knowing only the mean of the RNG bias. This implies that our experimental result is robust for any model underlying the estimated average RNG bias, for random bits produced up to 690 ns too early by the random number generator. PMID:27509823

  4. Loophole-free Bell test using electron spins in diamond: second experiment and additional analysis

    PubMed Central

    Hensen, B.; Kalb, N.; Blok, M. S.; Dréau, A. E.; Reiserer, A.; Vermeulen, R. F. L.; Schouten, R. N.; Markham, M.; Twitchen, D. J.; Goodenough, K.; Elkouss, D.; Wehner, S.; Taminiau, T. H.; Hanson, R.

    2016-01-01

    The recently reported violation of a Bell inequality using entangled electronic spins in diamonds (Hensen et al., Nature 526, 682–686) provided the first loophole-free evidence against local-realist theories of nature. Here we report on data from a second Bell experiment using the same experimental setup with minor modifications. We find a violation of the CHSH-Bell inequality of 2.35 ± 0.18, in agreement with the first run, yielding an overall value of S = 2.38 ± 0.14. We calculate the resulting P-values of the second experiment and of the combined Bell tests. We provide an additional analysis of the distribution of settings choices recorded during the two tests, finding that the observed distributions are consistent with uniform settings for both tests. Finally, we analytically study the effect of particular models of random number generator (RNG) imperfection on our hypothesis test. We find that the winning probability per trial in the CHSH game can be bounded knowing only the mean of the RNG bias. This implies that our experimental result is robust for any model underlying the estimated average RNG bias, for random bits produced up to 690 ns too early by the random number generator. PMID:27509823

  5. Augmenting a Waste Glass Mixture Experiment Study with Additional Glass Components and Experimental Runs

    SciTech Connect

    Piepel, Gregory F. ); Cooley, Scott K. ); Peeler, David K.; Vienna, John D. ); Edwards, Tommy B.

    2002-01-01

    A glass composition variation study (CVS) for high-level waste (HLW) stored in Idaho is being statistically designed and performed in phases over several years. The purpose of the CVS is to investigate and model how HLW-glass properties depend on glass composition. The resulting glass property-composition models will be used to develop desirable glass formulations and for other purposes. Phases 1 and 2 of the CVS have been completed and are briefly described. This paper focuses on the CVS Phase 3 experimental design, which was chosen to augment the Phase 1 and 2 data with additional data points, as well as to account for additional glass components not studied in Phases 1 and/or 2. In total, 16 glass components were varied in the Phase 3 experimental design. The paper describes how these Phase 3 experimental design augmentation challenges were addressed using the previous data, preliminary property-composition models, and statistical mixture experiment and optimal experimental design methods and software.

  6. The additive effect on suicidality of family history of suicidal behavior and early traumatic experiences.

    PubMed

    Lopez-Castroman, J; Guillaume, S; Olié, E; Jaussent, I; Baca-García, E; Courtet, P

    2015-01-01

    Family history of suicidal behavior and personal history of childhood abuse are reported risk factors for suicide attempts and suicide completion. We aim to quantify the additive effect of family history of suicidal behavior and different subtypes of childhood abuse on suicidal behavior. We examined a sample of 496 suicide attempters, comparing individuals with family history of suicidal behavior and personal history of childhood (physical or sexual) abuse, individuals with family history of suicidal behavior only, individuals with history of early traumatic experiences only, and individuals with none of these two risk factors with regards to suicidal features. An additive effect was found for the age at the first attempt in suicide attempters with both family history of suicidal behavior and either physical or sexual abuse. No significant interactions were found between family history of suicidal behavior and childhood trauma in relation to any characteristics of suicidal behavior. Subjects presenting family history of suicidal behavior and childhood abuse attempt suicide earlier in life than subjects with just one or none of them, particularly if they were sexually abused. Other suicidality indexes were only partially or not associated with this combination of risk factors. A careful assessment of patients with both family history of suicidal behavior and childhood abuse could help to prevent future suicide attempts, particularly in young people. PMID:25259671

  7. Disposition of transuranic residues from plutonium isentropic compression experiment (Pu-ice) conducted at Z machine

    SciTech Connect

    Goyal, Kapil K; French, David M; Humphrey, Betty J; Gluth, Jeffry

    2010-01-01

    In 1992, the U.S. Congress passed legislation to discontinue above- and below-ground testing of nuclear weapons. Because of this, the U.S. Department of Energy (DOE) must rely on laboratory experiments and computer-based calculations to verify the reliability of the nation's nuclear stockpile. The Sandia National Laboratories/New Mexico (SNL/NM) Z machine was developed by the DOE to support its science-based approach to stockpile stewardship. SNL/NM researchers also use the Z machine to test radiation effects on various materials in experiments designed to mimic nuclear explosions. Numerous components, parts, and materials have been tested. These experiments use a variety of radionuclides; however, plutonium (Pu) isotopes with greater than ninety-eight percent enrichment are the primary radionuclides used in the experiments designed for stockpile stewardship. In May 2006, SNL/NM received authority that the Z Machine Isentropic Compression Experiments could commence. Los Alamos National Laboratory (LANL) provided the plutonium targets and loaded the target assemblies, which were fabricated by SNL/NM. LANL shipped the loaded assemblies to SNL/NM for Z machine experiments. Three experiments were conducted from May through July 2006. The residues from each experiment, which weighed up to 913 pounds, were metallic and packaged into a respective 55-gallon drum each. Based on a memorandum of understanding between the two laboratories, LANL provides the plutonium samples and the respective radio-isotopic information. SNL/NM conducts the experiments and provides temporary storage for the drums until shipment to LANL for final waste certification for disposal at the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico. This paper presents a comprehensive approach for documenting generator knowledge for characterization of waste in cooperation with scientists at the two laboratories and addresses a variety of topics such as material control and accountability

  8. Effects of TiO2 addition on ionic conductivity of PVC/PEMA blend based composite polymer electrolyte

    NASA Astrophysics Data System (ADS)

    Subban, R. H. Y.; Sukri, Nursyazwani

    2015-08-01

    PVC/PEMA blend based polymer electrolytes with lithium bistrifluoromethane sulfonimide (LiN(CF3SO2)2) and PVC/PEMA/(LiN(CF3SO2)2-TiO2 films were prepared by solution cast technique. The sample containing 35 wt. % LiN(CF3SO2)2 exhibited the highest conductivity of 1.75 × 10-5 Scm-1. The conductivity of the sample increased to 2.12 × 10-5 Scm-1 and 4.61 × 10-5 Scm-1 when 4 wt. % and 10 wt. % of titanium dioxide (TiO2) was added to the sample at 65 wt. % PVC/PEMA-35 wt. % LiN(CF3SO2)2 composition respectively. The low increase in conductivity is attributed to two competing factors: increase in crystallinity as accounted by X-Ray diffraction (XRD) and decrease in glass transition temperature as accounted by differential scanning calorimetry (DSC).

  9. Effects of TiO{sub 2} addition on ionic conductivity of PVC/PEMA blend based composite polymer electrolyte

    SciTech Connect

    Subban, R. H. Y.; Sukri, Nursyazwani

    2015-08-28

    PVC/PEMA blend based polymer electrolytes with lithium bistrifluoromethane sulfonimide (LiN(CF{sub 3}SO{sub 2}){sub 2}) and PVC/PEMA/(LiN(CF{sub 3}SO{sub 2}){sub 2}-TiO{sub 2} films were prepared by solution cast technique. The sample containing 35 wt. % LiN(CF{sub 3}SO{sub 2}){sub 2} exhibited the highest conductivity of 1.75 × 10{sup −5} Scm{sup −1}. The conductivity of the sample increased to 2.12 × 10{sup −5} Scm{sup −1} and 4.61 × 10{sup −5} Scm{sup −1} when 4 wt. % and 10 wt. % of titanium dioxide (TiO{sub 2}) was added to the sample at 65 wt. % PVC/PEMA-35 wt. % LiN(CF{sub 3}SO{sub 2}){sub 2} composition respectively. The low increase in conductivity is attributed to two competing factors: increase in crystallinity as accounted by X-Ray diffraction (XRD) and decrease in glass transition temperature as accounted by differential scanning calorimetry (DSC)

  10. Conducting the NLM/AHCPR Large Scale Vocabulary Test: a distributed Internet-based experiment.

    PubMed Central

    McCray, A. T.; Cheh, M. L.; Bangalore, A. K.; Rafei, K.; Razi, A. M.; Divita, G.; Stavri, P. Z.

    1997-01-01

    The Large Scale Vocabulary Test, sponsored by the National Library of Medicine (NLM) and the Agency for Health Care Policy and Research (AHCPR), was conducted to determine the extent to which a combination of existing health-related terminologies cover vocabulary needed in health care information systems. The test was conducted over the Internet using a sophisticated World Wide Web interface with over 60 participants and over 40,000 terms submitted. This paper discusses the issues encountered in the design and execution of the experiment, including the design of the interface and the issues of recruitment, training, and guidance of remote participants over the Internet. Test data are currently undergoing expert review. Upon completion of the expert review, the results of the test will be fully reported. PMID:9357688

  11. Variable conductance heat pipe technology. [research project resulting in heat pipe experiment on OAO-3 satellite

    NASA Technical Reports Server (NTRS)

    Anderson, W. T.; Edwards, D. K.; Eninger, J. E.; Marcus, B. D.

    1974-01-01

    A research and development program in variable conductance heat pipe technology is reported. The project involved: (1) theoretical and/or experimental studies in hydrostatics, (2) hydrodynamics, (3) heat transfer into and out of the pipe, (4) fluid selection, and (5) materials compatibility. The development, fabrication, and test of the space hardware resulted in a successful flight of the heat pipe experiment on the OAO-3 satellite. A summary of the program is provided and a guide to the location of publications on the project is included.

  12. Comparison of Fire Model Predictions with Experiments Conducted in a Hangar With a 15 Meter Ceiling

    NASA Technical Reports Server (NTRS)

    Davis, W. D.; Notarianni, K. A.; McGrattan, K. B.

    1996-01-01

    The purpose of this study is to examine the predictive capabilities of fire models using the results of a series of fire experiments conducted in an aircraft hangar with a ceiling height of about 15 m. This study is designed to investigate model applicability at a ceiling height where only a limited amount of experimental data is available. This analysis deals primarily with temperature comparisons as a function of distance from the fire center and depth beneath the ceiling. Only limited velocity measurements in the ceiling jet were available but these are also compared with those models with a velocity predictive capability.

  13. STS-47 MS / PLC Lee conducts SLJ experiment M20 using the image furnace

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-47 Mission Specialist (MS) and Payload Commander (PLC) Mark C. Lee, wearing rubber gloves, prepares to load raw material (or crystal seed material) into the upper shaft (or lower shaft) of the Image Furnace. Lee is conducting Spacelab Japan (SLJ) experiment M20, Growth of Samarskite Crystal in Microgravity, during which a single crystal will be produced using the traveling solvent float zone method. The Image Furnace is located in SLJ NASDA Material Sciences Rack 8. SLJ science module is in the payload bay (PLB) of the Earth-orbiting Endeavour, Orbiter Vehicle (OV) 105.

  14. Feasibility of conducting a dynamic helium charging experiment for vanadium alloys in the advanced test reactor

    SciTech Connect

    Tsai, H.; Gomes, I.; Strain, R.V.; Smith, D.L.; Matsui, H.

    1996-10-01

    The feasibility of conducting a dynamic helium charging experiment (DHCE) for vanadium alloys in the water-cooled Advanced Test Reactor (ATR) is being investigated as part of the U.S./Monbusho collaboration. Preliminary findings suggest that such an experiment is feasible, with certain constraints. Creating a suitable irradiation position in the ATR, designing an effective thermal neutron filter, incorporating thermocouples for limited specimen temperature monitoring, and handling of tritium during various phases of the assembly and reactor operation all appear to be feasible. An issue that would require special attention, however, is tritium permeation loss through the capsule wall at the higher design temperatures (>{approx}600{degrees}C). If permeation is excessive, the reduced amount of tritium entering the test specimens would limit the helium generation rates in them. At the lower design temperatures (<{approx}425{degrees}C), sodium, instead of lithium, may have to be used as the bond material to overcome the tritium solubility limitation.

  15. A 201-MHz Normal Conducting RF Cavity for the International MICE Experiment

    SciTech Connect

    Li, D.; DeMello, A.J.; Virostek, Steve; S. Zisman, Michael; Rimmer, Robert

    2008-07-01

    MICE is a demonstration experiment for the ionization cooling of muon beams. Eight RF cavities are proposed to be used in the MICE cooling channel. These cavities will be operated in a strong magnetic field; therefore, they must be normal conducting. The cavity design and construction are based on the successful experience and techniques developed for a 201-MHz prototype cavity for the US MUCOOL program. Taking advantage of a muon beamâ s penetration property, the cavity employs a pair of curved thin beryllium windows to terminate conventional beam irises and achieve higher cavity shunt impedance. The cavity resembles a round, closed pillbox cavity. Two half-shells spun from copper sheets are joined by e-beam welding to form the cavity body. There are four ports on the cavity equator for RF couplers, vacuum pumping and field probes. The ports are formed by means of an extruding technique.

  16. Determinant for β-subunit regulation in high-conductance voltage-activated and Ca2+-sensitive K+ channels: An additional transmembrane region at the N terminus

    PubMed Central

    Wallner, Martin; Meera, Pratap; Toro, Ligia

    1996-01-01

    The pore-forming α subunit of large conductance voltage- and Ca2+-sensitive K (MaxiK) channels is regulated by a β subunit that has two membrane-spanning regions separated by an extracellular loop. To investigate the structural determinants in the pore-forming α subunit necessary for β-subunit modulation, we made chimeric constructs between a human MaxiK channel and the Drosophila homologue, which we show is insensitive to β-subunit modulation, and analyzed the topology of the α subunit. A comparison of multiple sequence alignments with hydrophobicity plots revealed that MaxiK channel α subunits have a unique hydrophobic segment (S0) at the N terminus. This segment is in addition to the six putative transmembrane segments (S1–S6) usually found in voltage-dependent ion channels. The transmembrane nature of this unique S0 region was demonstrated by in vitro translation experiments. Moreover, normal functional expression of signal sequence fusions and in vitro N-linked glycosylation experiments indicate that S0 leads to an exoplasmic N terminus. Therefore, we propose a new model where MaxiK channels have a seventh transmembrane segment at the N terminus (S0). Chimeric exchange of 41 N-terminal amino acids, including S0, from the human MaxiK channel to the Drosophila homologue transfers β-subunit regulation to the otherwise unresponsive Drosophila channel. Both the unique S0 region and the exoplasmic N terminus are necessary for this gain of function. PMID:8962157

  17. Determinant for beta-subunit regulation in high-conductance voltage-activated and Ca(2+)-sensitive K+ channels: an additional transmembrane region at the N terminus.

    PubMed

    Wallner, M; Meera, P; Toro, L

    1996-12-10

    The pore-forming alpha subunit of large conductance voltage- and Ca(2+)-sensitive K (MaxiK) channels is regulated by a beta subunit that has two membrane-spanning regions separated by an extracellular loop. To investigate the structural determinants in the pore-forming alpha subunit necessary for beta-subunit modulation, we made chimeric constructs between a human MaxiK channel and the Drosophila homologue, which we show is insensitive to beta-subunit modulation, and analyzed the topology of the alpha subunit. A comparison of multiple sequence alignments with hydrophobicity plots revealed that MaxiK channel alpha subunits have a unique hydrophobic segment (S0) at the N terminus. This segment is in addition to the six putative transmembrane segments (S1-S6) usually found in voltage-dependent ion channels. The transmembrane nature of this unique S0 region was demonstrated by in vitro translation experiments. Moreover, normal functional expression of signal sequence fusions and in vitro N-linked glycosylation experiments indicate that S0 leads to an exoplasmic N terminus. Therefore, we propose a new model where MaxiK channels have a seventh transmembrane segment at the N terminus (S0). Chimeric exchange of 41 N-terminal amino acids, including S0, from the human MaxiK channel to the Drosophila homologue transfers beta-subunit regulation to the otherwise unresponsive Drosophila channel. Both the unique S0 region and the exoplasmic N terminus are necessary for this gain of function. PMID:8962157

  18. Analysis of in-situ electrical conductivity data from the HFIR TRIST-ER1 experiment

    SciTech Connect

    Zinkle, S.J.; Snead, L.L.; Shikama, T.

    1997-08-01

    The current vs. applied voltage data generated from the HFIR TRIST-ER1 experiment have been analyzed to determine the electrical conductivity of the 15 aluminum oxide specimens and the MgO-insulated electrical cables as a function of irradiation dose. With the exception of the 0.05%Cr-doped sapphire (ruby) specimen, the electrical conductivity of the alumina specimens remained at the expected radiation induced conductivity (RIC) level of <10{sup -6} S/m during full-power reactor irradiation (10-16 kGy/s) at 450-500{degrees}C up to a maximum dose of {approximately}3 dpa. The ruby specimen showed a rapid initial increase in conductivity to {approximately}2 x 10{sup -4} S/m after {approximately}0.1 dpa, followed by a gradual decrease to <1 x 10{sup -6} S/m after 2 dpa. Nonohmic electrical behavior was observed in all of the specimens, and was attributed to preferential attraction of ionized electrons in the capsule gas to the unshielded low-side bare electrical leads emanating from the subcapsules. The electrical conductivity was determined from the slope of the specimen current vs. voltage curve at negative voltages, where the gas ionization effect was minimized. Dielectric breakdown tests performed on unirradiated mineral-insulated coaxial cables identical to those used in the high voltage coaxial cables during the 3-month irradiation is attributable to thermal dielectric breakdown in the glass seals at the end of the cables, as opposed to a radiation-induced electrical degradation (RIED) effect.

  19. An experiment in software reliability: Additional analyses using data from automated replications

    NASA Technical Reports Server (NTRS)

    Dunham, Janet R.; Lauterbach, Linda A.

    1988-01-01

    A study undertaken to collect software error data of laboratory quality for use in the development of credible methods for predicting the reliability of software used in life-critical applications is summarized. The software error data reported were acquired through automated repetitive run testing of three independent implementations of a launch interceptor condition module of a radar tracking problem. The results are based on 100 test applications to accumulate a sufficient sample size for error rate estimation. The data collected is used to confirm the results of two Boeing studies reported in NASA-CR-165836 Software Reliability: Repetitive Run Experimentation and Modeling, and NASA-CR-172378 Software Reliability: Additional Investigations into Modeling With Replicated Experiments, respectively. That is, the results confirm the log-linear pattern of software error rates and reject the hypothesis of equal error rates per individual fault. This rejection casts doubt on the assumption that the program's failure rate is a constant multiple of the number of residual bugs; an assumption which underlies some of the current models of software reliability. data raises new questions concerning the phenomenon of interacting faults.

  20. Additions and Improvements to the FLASH Code for Simulating High Energy Density Physics Experiments

    NASA Astrophysics Data System (ADS)

    Lamb, D. Q.; Daley, C.; Dubey, A.; Fatenejad, M.; Flocke, N.; Graziani, C.; Lee, D.; Tzeferacos, P.; Weide, K.

    2015-11-01

    FLASH is an open source, finite-volume Eulerian, spatially adaptive radiation hydrodynamics and magnetohydrodynamics code that incorporates capabilities for a broad range of physical processes, performs well on a wide range of computer architectures, and has a broad user base. Extensive capabilities have been added to FLASH to make it an open toolset for the academic high energy density physics (HEDP) community. We summarize these capabilities, with particular emphasis on recent additions and improvements. These include advancements in the optical ray tracing laser package, with methods such as bi-cubic 2D and tri-cubic 3D interpolation of electron number density, adaptive stepping and 2nd-, 3rd-, and 4th-order Runge-Kutta integration methods. Moreover, we showcase the simulated magnetic field diagnostic capabilities of the code, including induction coils, Faraday rotation, and proton radiography. We also describe several collaborations with the National Laboratories and the academic community in which FLASH has been used to simulate HEDP experiments. This work was supported in part at the University of Chicago by the DOE NNSA ASC through the Argonne Institute for Computing in Science under field work proposal 57789; and the NSF under grant PHY-0903997.

  1. Engineered soils for low-level radioactive waste disposal facilities: Effects of additives on the adsorptive behavior and hydraulic conductivity of natural soils

    SciTech Connect

    Katz, L.E.; Humphrey, D.N.; DeMascio, F.A.

    1996-12-31

    The siting of low-level radioactive waste disposal facilities requires locations having suitable soil materials beneath the proposed facility. These soils should be selected or designed to control water infiltration and ponding and enhance adsorption of radionuclides. This paper has investigated the effect of four soil additives on the hydraulic conductivity and adsorption characteristics of two natural soils, a glacial till and marine clay. The additives studied in this paper were andisol, bentonite, clinoptilolite and hematite. The results of the hydraulic conductivity testing indicated that remolding and recompacting the soils produced a more homogeneous soil having lower hydraulic conductivities. Comparison of the hydraulic conductivity and adsorptive behavior of the background soils, the additives, and mixtures of background soils and additives indicated that andisol and clinoptilolite provided the most improvement with respect to increasing adsorption capacity for iodide and strontium, respectively, with little effect on the hydraulic conductivity. The extent of adsorption and the effects of the additives on adsorption were highly pH dependent. The impact of the additives was most significant at acidic pH for both strontium and iodide adsorption because at high pH iodide adsorption was minimal for any of the materials tested and all of the background soils adsorbed a significant amount of strontium at high pH. These results suggest that engineered soils, comprised of a mixture of soil and additives, when used below a low-level radioactive waste disposal facility can enhance the ability of a site to retard off-site migration of radionuclides. 40 refs., 15 figs., 6 tabs.

  2. How to conduct a workshop on medical writing: Tips, advice and experience sharing.

    PubMed

    Rathore, Farooq Azam; Mansoor, Sahibzada Nasir

    2015-06-01

    Medical writing has become an essential skill for anybody in academia and engaged in teaching. Workshops on medical writing are an effective way to teach the essential skills of medical writing to students and faculty members. There is a huge demand for these workshops all around the globe. Usually there is no curriculum of medical writing for the undergraduates or dedicated structured training sessions for the faculty members. One of the authors won an Author AID grant to conduct a series of workshops on medical writing. Eight workshops were conducted in three months, benefitting more than 200 students and faculty staff. We share our experience of holding this successful series of workshops with the aim that it might serve as a guide for researchers and faculty members who are eager to share and transfer their skills and knowledge. We also offer lessons learnt during this educational activity, tips to improve the quality and delivery of the content with limited resources and maximizing the impact. Experienced medical writers need to conduct these workshops to transfer their skills and to facilitate their colleagues and students to become better medical writers. Planning, rehearsal, motivation, resource management, good team work, audience analysis and feedback can make a workshop successful. Well prepared workshop content delivered in an interactive way with a variety of activities makes the workshop an engaging and interesting educational activity. PMID:26060168

  3. Automated microbial metabolism laboratory. [design of advanced labeled release experiment based on single addition of soil and multiple sequential additions of media into test chambers

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The design and rationale of an advanced labeled release experiment based on single addition of soil and multiple sequential additions of media into each of four test chambers are outlined. The feasibility for multiple addition tests was established and various details of the methodology were studied. The four chamber battery of tests include: (1) determination of the effect of various atmospheric gases and selection of that gas which produces an optimum response; (2) determination of the effect of incubation temperature and selection of the optimum temperature for performing Martian biochemical tests; (3) sterile soil is dosed with a battery of C-14 labeled substrates and subjected to experimental temperature range; and (4) determination of the possible inhibitory effects of water on Martian organisms is performed initially by dosing with 0.01 ml and 0.5 ml of medium, respectively. A series of specifically labeled substrates are then added to obtain patterns in metabolic 14CO2 (C-14)O2 evolution.

  4. Additive Manufacturing, Design, Testing, and Fabrication: A Full Engineering Experience at JSC

    NASA Technical Reports Server (NTRS)

    Zusack, Steven

    2016-01-01

    I worked on several projects this term. While most projects involved additive manufacturing, I was also involved with two design projects, two testing projects, and a fabrication project. The primary mentor for these was Richard Hagen. Secondary mentors were Hai Nguyen, Khadijah Shariff, and fabrication training from James Brown. Overall, my experience at JSC has been successful and what I have learned will continue to help me in my engineering education and profession long after I leave. My 3D printing projects ranged from less than a 1 cubic centimeter to about 1 cubic foot and involved several printers using different printing technologies. It was exciting to become familiar with printing technologies such as industrial grade FDM (Fused Deposition Modeling), the relatively new SLA (Stereolithography), and PolyJet. My primary duty with the FDM printers was to model parts that came in from various sources to print effectively and efficiently. Using methods my mentor taught me and the Stratasys Insight software, I was able to minimize imperfections, hasten build time, improve strength for specific forces (tensile, shear, etc...), and reduce likelihood of a print-failure. Also using FDM, I learned how to repair a part after it was printed. This is done by using a special kind of glue that chemically melts the two faces of plastic parts together to form a fused interface. My first goal with SLA technology was to bring the printer back to operational readiness. In becoming familiar with the Pegasus SLA printer, I researched the leveling, laser settings, and different vats to hold liquid material. With this research, I was successfully able to bring the Pegasus back online and have successfully printed multiple sample parts as well as functional parts. My experience with PolyJet technology has been focused on an understanding of the abilities/limits, costs, and the maintenance for daily use. Still upcoming will be experience with using a composite printer that uses FDM

  5. Participation in the definition, conduct, and analysis of particle accelerator experiments for the first Spacelab Mission

    NASA Technical Reports Server (NTRS)

    Burch, J. L.

    1994-01-01

    The Space Experiments with Particle Accelerators (SEPAC) is a joint endeavor between NASA and the Institute of Space and Aeronautical Sciences (ISAS) in Japan. Its objectives are to use energetic electron beams to investigate beam-atmosphere interactions and beam-plasma interactions in the earth's upper atmosphere and ionosphere using the shuttle Spacelab. Two flights of SEPAC have occurred to date (Spacelab 1 on STS-9 in Nov.-Dec. 1983 and ATLAS 1 on STS-45 in Mar.-Apr. 1992). The SEPAC instrumentation is available for future missions, and the scientific results of the first two missions justify further investigations; however, at present there are no identifiable future flight opportunities. As specified in the contract, the primary purpose of this report is to review the scientific accomplishments of the ATLAS 1 SEPAC experiments, which have been documented in the published literature, with only a brief review of the earlier Spacelab 1 results. One of the main results of the Spacelab 1 SEPAC experiments was that the ejection of plasma from the magnetoplasmadynamic (MPD) arcjet was effective in maintaining vehicle charge neutralization during electron beam firings, but only for a brief period of 10 ms or so. Therefore, a xenon plasma contactor, which can provide continuous vehicle charge neutralization, was developed for the ATLAS 1 SEPAC experiments. Because of the successful operation of the plasma contactor on ATLAS 1, it was possible to perform experiments on beam-plasma interactions and beam-atmosphere interactions at the highest beam power levels of SEPAC. In addition, the ability of the plasma contactor to eject neutral xenon led to a successful experiment on the critical ionization velocity (CIV) phenomena on ATLAS 1.

  6. Development of a Laboratory Experiment to Derivate the Thermal Conductivity based on Electrical Resistivity Measurments

    NASA Astrophysics Data System (ADS)

    Vienken, T.; Firmbach, L.; Dietrich, P.

    2014-12-01

    In the course of the energy transition, the number of shallow geothermal systems is constantly growing. These systems allow the exploitation of renewable energy from the subsurface, reduced CO2 emission and additionally, energy storage. An efficient performance of geothermal systems strongly depends upon the availability of exploration data (e.g. thermal conductivity distribution). However, due to high exploration costs, the dimensioning of smaller plants (< 30 kW) is generally based on literature values. While standard in-situ-tests are persistent for larger scale projects, they yield only integral values, e.g. entire length of a borehole heat exchanger. Hence, exploring the distribution of the thermal conductivity as important soil parameter requires the development of new cost-efficient technologies. The general relationship between the electrical (RE) and the thermal resistivity (RT) can be described as log(RE) = CR log(RT) with CRas a multiplier depending on additional soil parameter (e.g. water content, density, porosity, grain size and distribution). Knowing the influencing factor of these additional determining parameters, geoelectrical measurements could provide a cost-efficient exploration strategy of the thermal conductivity for shallow geothermal sites. The aim of this study now is to define the multiplier CRexperimentally to conclude the exact correlation of the thermal and electrical behavior. The set-up consists of an acrylic glass tube with two current electrodes installed at the upper and lower end of the tube. Four electrode chains (each with eight electrodes) measure the potential differences in respect to an induced heat flux initiated by a heat plate. Additional, eight temperature sensors measure the changes of the temperature differences. First, we use this set-up to analyze the influence of soil properties based on differing homogenous sediments with known chemical and petro-physical properties. Further, we analyze the influence of the water

  7. Ten years' experience conducting the Aging Game workshop: was it worth it?

    PubMed

    Pacala, James T; Boult, Chad; Hepburn, Ken

    2006-01-01

    In the Aging Game, medical students experience simulated physical, sensory, and cognitive deficits that are associated with disability from chronic diseases. Since 1994, the University of Minnesota has presented an innovative version of the Aging Game as part of the curriculum in a required clinical clerkship. The experiences conducting the Aging Game over the past decade were reviewed, focusing on the resources necessary to produce it and on its worth as an educational tool. Because many of the reusable props were obtained free as donations, start-up material costs were calculated at 530 dollars. Personnel necessary for each half-day presentation of the Aging Game included two faculty and a minimum of five nonfaculty serving as facilitators; a staff coordinator was also essential. Quantitative student evaluations (N=673) exhibited mean ratings of 1.41, 1.35, and 1.40 (1=excellent) for overall value, teaching effectiveness, and quality of a postsimulation discussion. Written student comments regarding the strengths of the Aging Game centered on three major themes: mode of learning, especially using role playing and simulating deficits (total of 192 comments); attitudinal change, specifically raising awareness and stimulating reflection on the experiences of disabled older adults (121 comments); and educational value, particularly the Aging Game's capacity for creating a memorable impression (56 comments). Despite consuming significant personnel resources, the Minnesota version of the Aging Game is an effective tool for stimulating long-lasting awareness and understanding of key issues related to aging and geriatrics. PMID:16420212

  8. Nitrate removal in stream ecosystems measured by 15N addition experiments: Total uptake

    SciTech Connect

    Mulholland, Patrick J; Hall, Robert; Tank, Jennifer; Sobota, Daniel; O'Brien, Jon; Webster, Jackson; Valett, H. Maurice; Dodds, Walter; Poole, Geoff; Peterson, Chris G.; Meyer, Judy; McDowell, William; Johnson, Sherri; Hamilton, Stephen; Gregory, Stanley; Grimm, Nancy; Dahm, Cliff; Cooper, Lee W; Ashkenas, Linda; Thomas, Suzanne; Sheibley, Rich; Potter, Jody; Niederlehner, Bobbie; Johnson, Laura; Helton, Ashley; Crenshaw, Chelsea; Burgin, Amy; Bernot, Melody; Beaulieu, Jake; Arango, Clay

    2009-01-01

    We measured uptake length of {sup 15}NO{sub 3}{sup -} in 72 streams in eight regions across the United States and Puerto Rico to develop quantitative predictive models on controls of NO{sub 3}{sup -} uptake length. As part of the Lotic Intersite Nitrogen Experiment II project, we chose nine streams in each region corresponding to natural (reference), suburban-urban, and agricultural land uses. Study streams spanned a range of human land use to maximize variation in NO{sub 3}{sup -} concentration, geomorphology, and metabolism. We tested a causal model predicting controls on NO{sub 3}{sup -} uptake length using structural equation modeling. The model included concomitant measurements of ecosystem metabolism, hydraulic parameters, and nitrogen concentration. We compared this structural equation model to multiple regression models which included additional biotic, catchment, and riparian variables. The structural equation model explained 79% of the variation in log uptake length (S{sub Wtot}). Uptake length increased with specific discharge (Q/w) and increasing NO{sub 3}{sup -} concentrations, showing a loss in removal efficiency in streams with high NO{sub 3}{sup -} concentration. Uptake lengths shortened with increasing gross primary production, suggesting autotrophic assimilation dominated NO{sub 3}{sup -} removal. The fraction of catchment area as agriculture and suburban-urban land use weakly predicted NO{sub 3}{sup -} uptake in bivariate regression, and did improve prediction in a set of multiple regression models. Adding land use to the structural equation model showed that land use indirectly affected NO{sub 3}{sup -} uptake lengths via directly increasing both gross primary production and NO{sub 3}{sup -} concentration. Gross primary production shortened S{sub Wtot}, while increasing NO{sub 3}{sup -} lengthened S{sub Wtot} resulting in no net effect of land use on NO{sub 3}{sup -} removal.

  9. Nitrate removal in stream ecosystems measured by 15N addition experiments: Total uptake

    USGS Publications Warehouse

    Hall, R.O., Jr.; Tank, J.L.; Sobota, D.J.; Mulholland, P.J.; O'Brien, J. M.; Dodds, W.K.; Webster, J.R.; Valett, H.M.; Poole, G.C.; Peterson, B.J.; Meyer, J.L.; McDowell, W.H.; Johnson, S.L.; Hamilton, S.K.; Grimm, N. B.; Gregory, S.V.; Dahm, Clifford N.; Cooper, L.W.; Ashkenas, L.R.; Thomas, S.M.; Sheibley, R.W.; Potter, J.D.; Niederlehner, B.R.; Johnson, L.T.; Helton, A.M.; Crenshaw, C.M.; Burgin, A.J.; Bernot, M.J.; Beaulieu, J.J.; Arangob, C.P.

    2009-01-01

    We measured uptake length of 15NO-3 in 72 streams in eight regions across the United States and Puerto Rico to develop quantitative predictive models on controls of NO-3 uptake length. As part of the Lotic Intersite Nitrogen eXperiment II project, we chose nine streams in each region corresponding to natural (reference), suburban-urban, and agricultural land uses. Study streams spanned a range of human land use to maximize variation in NO-3 concentration, geomorphology, and metabolism. We tested a causal model predicting controls on NO-3 uptake length using structural equation modeling. The model included concomitant measurements of ecosystem metabolism, hydraulic parameters, and nitrogen concentration. We compared this structural equation model to multiple regression models which included additional biotic, catchment, and riparian variables. The structural equation model explained 79% of the variation in log uptake length (S Wtot). Uptake length increased with specific discharge (Q/w) and increasing NO-3 concentrations, showing a loss in removal efficiency in streams with high NO-3 concentration. Uptake lengths shortened with increasing gross primary production, suggesting autotrophic assimilation dominated NO-3 removal. The fraction of catchment area as agriculture and suburban-urban land use weakly predicted NO-3 uptake in bivariate regression, and did improve prediction in a set of multiple regression models. Adding land use to the structural equation model showed that land use indirectly affected NO-3 uptake lengths via directly increasing both gross primary production and NO-3 concentration. Gross primary production shortened SWtot, while increasing NO-3 lengthened SWtot resulting in no net effect of land use on NO- 3 removal. ?? 2009.

  10. 5 CFR 1001.101 - In addition to this part, what other rules of conduct apply to Office of Personnel Management...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false In addition to this part, what other rules of conduct apply to Office of Personnel Management employees? 1001.101 Section 1001.101 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) REGULATIONS GOVERNING EMPLOYEES OF THE OFFICE OF PERSONNEL MANAGEMENT OPM...

  11. 5 CFR 1001.101 - In addition to this part, what other rules of conduct apply to Office of Personnel Management...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false In addition to this part, what other rules of conduct apply to Office of Personnel Management employees? 1001.101 Section 1001.101 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) REGULATIONS GOVERNING EMPLOYEES OF THE OFFICE OF PERSONNEL MANAGEMENT OPM...

  12. Low Conductive Thermal Barrier Coatings Produced by Ion Beam Assisted EB-PVD with Controlled Porosity, Microstructure Refinement and Alloying Additions for High Temperature Applications

    NASA Technical Reports Server (NTRS)

    Wolfe, Douglas E.; Singh, Jogender

    2005-01-01

    Various advanced Hafnia-based thermal barrier coatings (TBC) were applied on nickel-based superalloy coupons by electron beam physical vapor deposition. In addition, microstructural modifications to the coating material were made in an effort to reduce the thermal conductivity of the coating materials. Various processing parameters and coating system modifications were made in order to deposit the alloyed TBC with the desired microstructure and thus coating performance, some of which include applying coatings at substrate temperatures of 1150 C on both PtAl and CoNiCrAlY bond coated samples, as well as using 8YSZ as a bond layer. In addition, various characterization techniques including thermal cyclic tests, scanning electron microscopy, x-ray diffraction, thermal conductivity, and reflectivity measurements were performed. Although the coating microstructure was never fully optimized due to funding being cut short, significant reductions in thermal conductivity were accomplished through both chemistry changes (composition) and microstructural modifications.

  13. Hydraulic Experiments for Determination of In-situ Hydraulic Conductivity of Submerged Sediments

    PubMed Central

    Lee, Bong-Joo; Lee, Ji-Hoon; Yoon, Heesung; Lee, Eunhee

    2015-01-01

    A new type of in-situ hydraulic permeameter was developed to determine vertical hydraulic conductivity (VHC) of saturated sediments from hydraulic experiments using Darcy's law. The system allows water to move upward through the porous media filled in the permeameter chamber driven into sediments at water-sediment interface. Darcy flux and hydraulic gradient can be measured using the system, and the VHC can be determined from the relationship between them using Darcy's law. Evaluations in laboratory and in field conditions were performed to see if the proposed permeameter give reliable and valid measures of the VHC even where the vertical flow at water-sediment interface and fluctuation of water stage exist without reducing the accuracy of the derived VHC. Results from the evaluation tests indicate that the permeameter proposed in this study can be used to measure VHC of saturated sandy sediments at water-sediment interface in stream and marine environment with high accuracy. PMID:25604984

  14. Experiences with the magnetism of conducting loops: Historical instruments, experimental replications, and productive confusions

    NASA Astrophysics Data System (ADS)

    Cavicchi, Elizabeth

    2003-02-01

    This study investigates nineteenth century laboratory work on electromagnetism through historical accounts and experimental replications. Oersted found that when a magnetic needle was placed in varying positions around a conducting wire, its orientation changed: in moving from a spot above the wire to one below, its sense inverted. This behavior was confusing and provocative. Early experimenters such as Johann Schweigger, Johann Poggendorff, and James Cumming engaged it by bending wire into loops. These loops, which increased the magnetic effect on a compass placed within, also provided evidence of their understanding and confusion. Coiling conducting wires around iron magnetized it, but when some wires coiled oppositely from others, the effect diminished. This effect confused contemporaries of Joseph Henry who made electromagnets, and amateurs later in the century who constructed multisection induction coils. I experienced these confusions myself while working with multilayer coils and induction coils that I made to replicate the historical instruments. This study shows how confusion can be a productive element in learning, by engaging learners to ask questions and invent experiments. By providing space for learners' confusions, teachers can support the development of their students' physical understandings.

  15. Controlled Quantized Conductance Steps Using a Simple Mechanical System: An Undergraduate Lab Experiment

    NASA Astrophysics Data System (ADS)

    Burnett, Christopher; Tolley, Robert; Silvidi, Antony; Eid, Khalid

    2011-10-01

    We demonstrate clear quantized conductance steps in mechanical break junctions (MBJ) based on a gold wire, a springy-steel bending beam, a micrometer, a 1.5V battery , and a Teflon disc that we rotate manually. The voltage across the wire is measured using a NI-DAQ assistant unit and a simple LabVIEW program. As the wire is stretched, its resistance (i.e. voltage across it) increases gradually then follows a stair-case- like shape, which is a hallmark of quantized conductance, with steps at values of 25.8 kφ/2n, where n is an integer. The resistance jumps are clearer and more distinct for smaller n and become closer for larger n, which is a demonstration of the Correspondence Principle. The quantization occurs when the wire is thin enough that its diameter is comparable to the de Broglie wave length of the current-carrying electrons and is a direct consequence of confinement. This experiment is designed for sophomore/junior level undergraduate labs.

  16. Effect of adverse childhood experiences on physical health in adulthood: Results of a study conducted in Baghdad city

    PubMed Central

    Al-Shawi, Ameel F.; Lafta, Riyadh K.

    2015-01-01

    Background: Studies have revealed a powerful relationship between adverse childhood experiences (ACEs) and physical and mental health in adulthood. Literature documents the conversion of traumatic emotional experiences in childhood into organic disease later in life. Objective: The aim was to estimate the effect of childhood experiences on the physical health of adults in Baghdad city. Subjects and Methods: A cross-sectional study was conducted from January 2013 to January 2014. The study sample was drawn from Baghdad city. Multistage sampling techniques were used in choosing 13 primary health care centers and eight colleges of three universities in Baghdad. In addition, teachers of seven primary schools and two secondary schools were chosen by a convenient method. Childhood experiences were measured by applying a modified standardized ACEs-International Questionnaire form and with questions for bonding to family and parental monitoring. Physical health assessment was measured by a modified questionnaire derived from Health Appraisal Questionnaire of Centers for Disease Control and Prevention. The questionnaire includes questions on cerebrovascular diseases, diabetes mellitus, tumor, respiratory and gastrointestinal diseases. Results: Logistic regression model showed that a higher level of bonding to family (fourth quartile) is expected to reduce the risk of chronic physical diseases by almost the half (odds ratio = 0.57) and exposure to a high level of household dysfunction and abuse (fourth quartile) is expected to increase the risk of chronic physical diseases by 81%. Conclusion: Childhood experiences play a major role in the determination of health outcomes in adulthood, and early prevention of ACEs. Encouraging strong family bonding can promote physical health in later life. PMID:25983602

  17. Thermal conductivity of Zn, Pr and Tb doped YBCO single crystals: Theory and experiment

    SciTech Connect

    Henning, P.F.; Cao, G.; Crow, J.E.

    1995-08-01

    The thermal conductivity K(T) vs temperature has been measured for (Y,Pr)Ba{sub 2}Cu{sub 3}O{sub 7}, (Y,Tb)Ba{sub 2}Cu{sub 3}O{sub 7} and YBa{sub 2}(Cu,Zn){sub 3}O{sub 7} single crystals from 10{le}T{le}280K. For YBa{sub 2}Cu{sub 3}O{sub 7} (YBCO), a strong enhancement in K(T) is observed for T{le}T{sub c} with a peak in K(T) at approximately T{approx}T{sub c}/2 with a sharp change in slope of K(T) at T{sub c}. These results are similar to those reported previously. For the selectively doped YBCO, the peak in K(T) is shifted to lower temperatures and occurs at T{approx}20K independent of T{sub c} and the impurity concentration. In addition, the sharp change in slope of K(T) at T{sub c} is not apparent for the doped crystals. These results are discussed along with a theoretical model for electronic conduction including both impurity and inelastic scattering from spin fluctuations.

  18. Stimulated Raman scatter analyses of experiments conducted at the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Hinkel, D. E.

    2010-11-01

    The recent energetics campaignootnotetextN. B. Meezan et al., Phys. Plasmas 17, 056304 (2010). conducted at the National Ignition Facility in Fall, 2009 achieved its two main goals: providing radiation drive and symmetry suitable for subsequent ignition experiments. Many diagnostics were fielded during this campaign, one of which provided a time-resolved wavelength spectrum of light reflected from the target by stimulated Raman scatter (SRS). SRS occurs when incident light reflects off self-generated electron plasma waves. The SRS spectrum of an inner cone quad has provided insight into these experiments. Analyses indicate that synthetic SRS diagnostics better match those of experiments when an atomic physics model with greater emissivity is utilized, along with less inhibited electron transport (higher flux, with, ideally, nonlocal electron transport). With these models,ootnotetextM. D. Rosen, this conference. SRS primarily occurs in a region of the target where nearest-neighbor 23^o quads significantly overlap the diagnosed 30^o quad. This increases the gain at lower density (lower wavelength), a feature consistent with experimental results. Other predicted features, such as the direction and spreading of the SRS as well as its intensity, are also in better agreement with experiment. Inclusion of this effect of multiple beams sharing a reflected SRS light wave has resulted in modifications to our laser-plasma interaction codes.ootnotetextC. H. Still, this conference.^,ootnotetextD. J. Strozzi, E. A. Williams, D. E. Hinkel et al., Phys. Plasmas 15, 102703 (2008).^,ootnotetextR. L. Berger, C. H. Still, E. A. Williams, and A. B. Langdon, Phys. Plasmas 5, 4337 (1998); C. H. Still, R. L. Berger, A. B. Langdon, D. E. Hinkel, L. J. Suter, and E. A. Williams, Phys. Plasmas , 2023 (2000); D. E. Hinkel, D. A. Callahan, A. B. Langdon, S. H. Langer, C. H. Still, and E. A. Williams, Phys. Plasmas 15, 056314 (2008). These improved capabilities are being tested by making

  19. Enhanced sinterability and conductivity of BaZr0.3Ce0.5Y0.2O3-δ by addition of bismuth oxide for proton conducting solid oxide fuel cells

    NASA Astrophysics Data System (ADS)

    Gui, Liangqi; Ling, Yihan; Li, Geng; Wang, Zhihao; Wan, Yanhong; Wang, Ranran; He, Beibei; Zhao, Ling

    2016-01-01

    The effect of bismuth oxide addition on the sintering behavior and electrical properties of BaZr0.3Ce0.5Y0.2O3-δ (BZCY) as an electrolyte for proton conducting solid oxide fuel cells (H-SOFCs) is studied. The introduction of Bi2O3 is beneficial to improving sinterability of BZCY, resulting in high density. Meanwhile, the conductivity test indicates that BaZr0.3Ce0.5Y0.2O3-δ - 2 mol% Bi2O3 (BZCY-2) promises the highest conductivities. Further, single cells with BZCY-2 as the electrolyte are fabricated and evaluated. The cell with BZCY-2 presents excellent power densities, which reaches 0.67, 0.44, and 0.27 mW cm-2 at 700, 650, and 600 °C, respectively. The conductivities of BZCY-2 film are higher than BZCY in this work and other reported BZCY films. The encouraging results suggest that the addition of a small amount (2 mol%) of Bi2O3 to BZCY can significantly promote sinterability and electrical conductivity for H-SOFCs.

  20. Understanding the Undergraduate Experience of the Baccalaureate Nursing Student with English as an Additional Language

    ERIC Educational Resources Information Center

    Dzubaty, Dolores R.

    2013-01-01

    Disparities exist in healthcare related to language barriers and lack of cultural understanding between caregivers and recipients. Increasing the linguistic and cultural diversity of caregivers may decrease the healthcare disparities observed. The research study described in this manuscript was conducted to explore the undergraduate student…

  1. Examining the Influence of Additional Field-Based Experiences on Pre-Service Teachers and Their Perceived Ability to Teach

    ERIC Educational Resources Information Center

    Clark, Sarah K.

    2012-01-01

    In an attempt to analyse more closely the training experiences of pre-service teachers, the author conducted an exploratory quasi-experimental study at a university located in the Rocky Mountain region of the USA. All students who were enrolled in the same reading methods course (but enrolled in different sections) were invited to participate in…

  2. Decision-making under uncertainty: results from an experiment conducted at EGU 2012

    NASA Astrophysics Data System (ADS)

    Ramos, Maria-Helena; van Andel, Schalk Jan; Pappenberger, Florian

    2013-04-01

    Do probabilistic forecasts lead to better decisions? At the EGU General Assembly 2012, we conducted a laboratory-style experiment to address this question. Several cases of flood forecasts and a choice of actions to take were presented as part of a game to participants, who acted as decision makers. Participants were prompted to make decisions when forecasts were provided with and without uncertainty information. They had to decide whether to open or not a gate which was the inlet of a retention basin designed to protect a town. The rules were such that: if they decided to open the gate, the retention basin was flooded and the farmers in this basin demanded a compensation for flooding their land; if they decided not to open the gate and a flood occurred on the river, the town was flooded and they had to pay a fine to the town. Participants were encouraged to keep note of their individual decisions in a worksheet. About 100 worksheets were collected at the end of the game and the results of their evaluation are presented here. In general, they show that decisions are based on a combination of what is displayed by the expected (forecast) value and what is given by the uncertainty information. In the absence of uncertainty information, decision makers are compelled towards a more risk-averse attitude. Besides, more money was lost by a large majority of participants when they had to make decisions without uncertainty information. Limitations of the experiment setting are discussed, as well as the importance of the development of training tools to increase effectiveness in the use of probabilistic predictions to support decisions under uncertainty.

  3. Using Embryology Screencasts: A Useful Addition to the Student Learning Experience?

    ERIC Educational Resources Information Center

    Evans, Darrell J. R.

    2011-01-01

    Although podcasting has been a well used resource format in the last few years as a way of improving the student learning experience, the inclusion of enhanced audiovisual formats such as screencasts has been less used, despite the advantage that they work well for both visual and auditory learners. This study examines the use of and student…

  4. Designing Location-Based Learning Experiences for People with Intellectual Disabilities and Additional Sensory Impairments

    ERIC Educational Resources Information Center

    Brown, David J.; McHugh, David; Standen, Penny; Evett, Lindsay; Shopland, Nick; Battersby, Steven

    2011-01-01

    The research reported here is part of a larger project which seeks to combine serious games (or games-based learning) with location-based services to help people with intellectual disabilities and additional sensory impairments to develop work based skills. Specifically this paper reports on where these approaches are combined to scaffold the…

  5. Percolation threshold of graphene nanosheets as conductive additives in Li4Ti5O12 anodes of Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Zhang, Biao; Yu, Yang; Liu, Yusi; Huang, Zhen-Dong; He, Yan-Bing; Kim, Jang-Kyo

    2013-02-01

    Graphene nanosheets (GNSs) have been considered as potential conductive additives for electrodes in Li-ion batteries to replace the existing carbon black (CB). Graphene has exceptionally high aspect ratio and excellent electrical conductivity, enabling the formation of extensive conductive networks at a much lower content than CB. This paper reports the beneficial effects of GNSs with a low percolation threshold on electrochemical performance of Li4Ti5O12 (LTO) anodes. The experimental results show that the GNSs with a diameter of 46 μm and a thickness of 4.5 nm have a percolation threshold of 1.8 wt%. The prediction based on the interparticle distance concept gives a percolation threshold of 0.54 wt% for GNSs, which is almost an order of magnitude lower than that for CB particles. The substantially low percolation along with a high electrical conductivity of GNSs explains why the LTO anodes containing only 5 wt% GNSs deliver a much better rate capability than those with 15 wt% CB. However, a higher GNS content of 10 wt% results in re-stacking GNSs, deteriorating the diffusion of Li ions through the thickness of GNSs. The parametric study indicates that the percolation threshold of GNSs is inversely proportional to the aspect ratio of GNSs.Graphene nanosheets (GNSs) have been considered as potential conductive additives for electrodes in Li-ion batteries to replace the existing carbon black (CB). Graphene has exceptionally high aspect ratio and excellent electrical conductivity, enabling the formation of extensive conductive networks at a much lower content than CB. This paper reports the beneficial effects of GNSs with a low percolation threshold on electrochemical performance of Li4Ti5O12 (LTO) anodes. The experimental results show that the GNSs with a diameter of 46 μm and a thickness of 4.5 nm have a percolation threshold of 1.8 wt%. The prediction based on the interparticle distance concept gives a percolation threshold of 0.54 wt% for GNSs, which is almost

  6. Laser Additive Melting and Solidification of Inconel 718: Finite Element Simulation and Experiment

    NASA Astrophysics Data System (ADS)

    Romano, John; Ladani, Leila; Sadowski, Magda

    2016-03-01

    The field of powdered metal additive manufacturing is experiencing a surge in public interest finding uses in aerospace, defense, and biomedical industries. The relative youth of the technology coupled with public interest makes the field a vibrant research topic. The authors have expanded upon previously published finite element models used to analyze the processing of novel engineering materials through the use of laser- and electron beam-based additive manufacturing. In this work, the authors present a model for simulating fabrication of Inconel 718 using laser melting processes. Thermal transport phenomena and melt pool geometries are discussed and validation against experimental findings is presented. After comparing experimental and simulation results, the authors present two correction correlations to transform the modeling results into meaningful predictions of actual laser melting melt pool geometries in Inconel 718.

  7. Rocket/Radar Sporadic-E Experiment Conducted during the El Coqui 2 Campaign

    NASA Technical Reports Server (NTRS)

    Pfaff, R.F.; Acuna, M.; Bounds, S.; Freudenreich, H.; Clemmons, J.; Earle, G.; Heelis, R.; Kudeki, E.; Franke, S.; Larsen, M.

    1999-01-01

    In order to investigate the complex electrodynamics and neutral-plasma coupling inherent to sporadic-E layers in the earth's mid-latitude ionosphere, a series of rocket/radar experiments were planned as part of the NASA El Coqui H Campaign from Tortuguero Launch Range, Puerto Rico, in March-April, 1998. The rocket experiments consisted of two pairs of "mother-daughter" payloads with limited apogees so that the payloads "hovered" in the sporadic-E region (95-125 km). Each payload pair included vector DC and AC electric field detectors, a highly accurate flux-gate DC magnetometer, an ion mass spectrometer, an ionization gauge, and spaced-electric field receivers to measure the wavelength and phase velocity of the unstable plasma waves. Separate rockets were included to simultaneously carry aloft TMA trails to measure the neutral wind and its velocity shear, believed responsible for the sporadic-E layer formation. In addition to the rocket experiments, incoherent scatter radar measurements of plasma density and drift velocity were gathered almost every night during the 3 week campaign. Continuous VHF backscatter radar operations were carried out from a site near Salinas, Puerto Rico, where 3-m backscatter echoes were observed associated with sporadic-E and other types of low altitude ionospheric layers. Other radars that operated during the campaign included an HF backscatter system near Ponce, Puerto Rico, and a second VHF backscatter radar set up near Aguadila Puerto Rico. On 24 March 1998, one of the instrumented rockets was launched, attaining an apogee of 129 km. The payloads successfully pierced an intense sporadic-E layer observed by both the Arecibo radar and the in-situ density and ion mass spectrometer probes. In-situ DC electric fields revealed very low (about 1-2 mV/m) ambient fields with small amplitude structures of the same order. No high frequency (short scale) waves were observed, consistent with the VHF backscatter observations at the time of the

  8. Additional results on space environmental effects on polymer matrix composites: Experiment A0180

    NASA Technical Reports Server (NTRS)

    Tennyson, R. C.

    1992-01-01

    Additional experimental results on the atomic oxygen erosion of boron, Kevlar, and graphite fiber reinforced epoxy matrix composites are presented. Damage of composite laminates due to micrometeoroid/debris impacts is also examined with particular emphasis on the relationship between damage area and actual hole size due to particle penetration. Special attention is given to one micrometeoroid impact on an aluminum base plate which resulted in ejecta visible on an adjoining vertical flange structure.

  9. 21 CFR 101.108 - Temporary exemptions for purposes of conducting authorized food labeling experiments.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... authorized food labeling experiments. 101.108 Section 101.108 Food and Drugs FOOD AND DRUG ADMINISTRATION... labeling experiments. (a) The food industry is encouraged to experiment voluntarily, under controlled... experiment that requires exemptions from certain requirements of §§ 101.9 and 105.66 of this chapter...

  10. 21 CFR 101.108 - Temporary exemptions for purposes of conducting authorized food labeling experiments.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... authorized food labeling experiments. 101.108 Section 101.108 Food and Drugs FOOD AND DRUG ADMINISTRATION... labeling experiments. (a) The food industry is encouraged to experiment voluntarily, under controlled... experiment that requires exemptions from certain requirements of §§ 101.9 and 105.66 of this chapter...

  11. 21 CFR 101.108 - Temporary exemptions for purposes of conducting authorized food labeling experiments.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... authorized food labeling experiments. 101.108 Section 101.108 Food and Drugs FOOD AND DRUG ADMINISTRATION... labeling experiments. (a) The food industry is encouraged to experiment voluntarily, under controlled... experiment that requires exemptions from certain requirements of §§ 101.9 and 105.66 of this chapter...

  12. 21 CFR 101.108 - Temporary exemptions for purposes of conducting authorized food labeling experiments.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... authorized food labeling experiments. 101.108 Section 101.108 Food and Drugs FOOD AND DRUG ADMINISTRATION... labeling experiments. (a) The food industry is encouraged to experiment voluntarily, under controlled... experiment that requires exemptions from certain requirements of §§ 101.9 and 105.66 of this chapter...

  13. 21 CFR 101.108 - Temporary exemptions for purposes of conducting authorized food labeling experiments.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... authorized food labeling experiments. 101.108 Section 101.108 Food and Drugs FOOD AND DRUG ADMINISTRATION... labeling experiments. (a) The food industry is encouraged to experiment voluntarily, under controlled... experiment that requires exemptions from certain requirements of §§ 101.9 and 105.66 of this chapter...

  14. Changes in water, carbon, and nitrogen fluxes with the addition of biochar to soils: lessons learned from laboratory and greenhouse experiments

    NASA Astrophysics Data System (ADS)

    Barnes, R. T.; Gallagher, M. E.; Masiello, C. A.; Liu, Z.; Dugan, B.; Rudgers, J. A.

    2011-12-01

    The addition of biochar to agricultural soils has the potential to provide a number of ecosystem services, ranging from carbon (C) sequestration to increased soil fertility and crop production. It is estimated that 0.5 to 0.9 Pg of C yr-1 can be sequestered through the addition of biochar to soils, significantly increasing the charcoal flux to the biosphere over natural inputs from fire (0.05 to 0.20 Pg C yr-1). There remain large uncertainties about biochar mobility within the environment, making it a challenge to assess the ecosystem residence time of biochar. We conducted laboratory and greenhouse experiments to understand how soil amendment with laboratory-produced biochar changes water, C, and nitrogen (N) fluxes from soils. We used column experiments to assess how biochar amendment to three types of soils (sand, organic, clay-rich) affected hydraulic conductivity and dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) fluxes. Results varied with soil type; biochar significantly decreased the hydraulic conductivity of the sand and organic soils by a factor of 10.6 and 2.7, respectively. While not statistically significant, biochar addition increased the hydraulic conductivity of the clay-rich soil by 50% on average. The addition of biochar significantly increased the DOC fluxes from the C-poor sand and clay soils while it significantly decreased the DOC flux from the organic-rich soil. In contrast, TDN fluxes decreased with biochar additions from all soil types, though the results were not statistically significant from the clay-rich soil. These laboratory experiments suggest that changes in the hydraulic conductivity of soil due to biochar amendments could play a significant role in understanding how biochar additions to agricultural fields will change watershed C and N dynamics. We additionally conducted a 28-day greenhouse experiment with sorghum plants using a three-way factorial treatment (water availability x biochar x mycorrhizae) to

  15. Experiments to Populate and Validate a Processing Model for Polyurethane Foam: Additional Data for Structural Foams.

    SciTech Connect

    Rao, Rekha R.; Celina, Mathias C.; Giron, Nicholas Henry; Long, Kevin Nicholas; Russick, Edward M.

    2015-01-01

    We are developing computational models to help understand manufacturing processes, final properties and aging of structural foam, polyurethane PMDI. Th e resulting model predictions of density and cure gradients from the manufacturing process will be used as input to foam heat transfer and mechanical models. BKC 44306 PMDI-10 and BKC 44307 PMDI-18 are the most prevalent foams used in structural parts. Experiments needed to parameterize models of the reaction kinetics and the equations of motion during the foam blowing stages were described for BKC 44306 PMDI-10 in the first of this report series (Mondy et al. 2014). BKC 44307 PMDI-18 is a new foam that will be used to make relatively dense structural supports via over packing. It uses a different catalyst than those in the BKC 44306 family of foams; hence, we expect that the reaction kineti cs models must be modified. Here we detail the experiments needed to characteriz e the reaction kinetics of BKC 44307 PMDI-18 and suggest parameters for the model based on these experiments. In additi on, the second part of this report describes data taken to provide input to the preliminary nonlinear visco elastic structural response model developed for BKC 44306 PMDI-10 foam. We show that the standard cu re schedule used by KCP does not fully cure the material, and, upon temperature elevation above 150 o C, oxidation or decomposition reactions occur that alter the composition of the foam. These findings suggest that achieving a fully cured foam part with this formulation may be not be possible through therma l curing. As such, visco elastic characterization procedures developed for curing thermosets can provide only approximate material properties, since the state of the material continuously evolves during tests.

  16. Additive manufacture (3d printing) of plasma diagnostic components and assemblies for fusion experiments

    NASA Astrophysics Data System (ADS)

    Sieck, Paul; Woodruff, Simon; Stuber, James; Romero-Talamas, Carlos; Rivera, William; You, Setthivoine; Card, Alexander

    2015-11-01

    Additive manufacturing (or 3D printing) is now becoming sufficiently accurate with a large range of materials for use in printing sensors needed universally in fusion energy research. Decreasing production cost and significantly lowering design time of energy subsystems would realize significant cost reduction for standard diagnostics commonly obtained through research grants. There is now a well-established set of plasma diagnostics, but these expensive since they are often highly complex and require customization, sometimes pace the project. Additive manufacturing (3D printing) is developing rapidly, including open source designs. Basic components can be printed for (in some cases) less than 1/100th costs of conventional manufacturing. We have examined the impact that AM can have on plasma diagnostic cost by taking 15 separate diagnostics through an engineering design using Conventional Manufacturing (CM) techniques to determine costs of components and labor costs associated with getting the diagnostic to work as intended. With that information in hand, we set about optimizing the design to exploit the benefits of AM. Work performed under DOE Contract DE-SC0011858.

  17. Experiences of clinical tutors with English as an additional language (EAL) students.

    PubMed

    Lu, Hongyan; Maithus, Caroline

    2012-11-01

    Clinical tutors, referred to in the international literature as clinical supervisors, facilitators, mentors or instructors, are responsible for providing and supervising workplace learning opportunities for groups of Bachelor of Nursing (BN) students. They also play a key role in assessing students. The role modeling and support provided by both clinical tutors and registered nurses (RN) or nurse preceptors helps students become familiar with the language in which nursing work is realised. As BN student cohorts in New Zealand have become more diverse in terms of cultures, ethnicities and language backgrounds, clinical tutors have to directly facilitate the development of context-specific and client-focused communication skills for students who speak English as an additional language. We undertook a study which looked at the perceptions of new nursing graduates with English as an additional language (EAL) on the development of spoken language skills for the clinical workplace. As well as interviewing graduates, we spoke to four clinical tutors in order to elicit their views on the language development of EAL students in previous cohorts. This article reports on the themes which emerged from the interviews with the tutors. These include goal setting for communication, integrating students into nursing work, making assessment less stressful, and endorsing independent learning strategies. Based on their observations and on other published research we make some suggestions about ways both clinical tutors and EAL students within their teaching groups could be supported in the development of communication skills for clinical practice. PMID:23421011

  18. Percolation threshold of graphene nanosheets as conductive additives in Li4Ti5O12 anodes of Li-ion batteries.

    PubMed

    Zhang, Biao; Yu, Yang; Liu, Yusi; Huang, Zhen-Dong; He, Yan-bing; Kim, Jang-Kyo

    2013-03-01

    Graphene nanosheets (GNSs) have been considered as potential conductive additives for electrodes in Li-ion batteries to replace the existing carbon black (CB). Graphene has exceptionally high aspect ratio and excellent electrical conductivity, enabling the formation of extensive conductive networks at a much lower content than CB. This paper reports the beneficial effects of GNSs with a low percolation threshold on electrochemical performance of Li(4)Ti(5)O(12) (LTO) anodes. The experimental results show that the GNSs with a diameter of 46 μm and a thickness of 4.5 nm have a percolation threshold of 1.8 wt%. The prediction based on the interparticle distance concept gives a percolation threshold of 0.54 wt% for GNSs, which is almost an order of magnitude lower than that for CB particles. The substantially low percolation along with a high electrical conductivity of GNSs explains why the LTO anodes containing only 5 wt% GNSs deliver a much better rate capability than those with 15 wt% CB. However, a higher GNS content of 10 wt% results in re-stacking GNSs, deteriorating the diffusion of Li ions through the thickness of GNSs. The parametric study indicates that the percolation threshold of GNSs is inversely proportional to the aspect ratio of GNSs. PMID:23381093

  19. Cognitive and affective empathy in children with conduct problems: additive and interactive effects of callous-unemotional traits and autism spectrum disorders symptoms.

    PubMed

    Pasalich, Dave S; Dadds, Mark R; Hawes, David J

    2014-11-30

    Callous-unemotional (CU) traits and autism spectrum disorders (ASD) symptoms are characterized by problems in empathy; however, these behavioral features are rarely examined together in children with conduct problems. This study investigated additive and interactive effects of CU traits and ASD symptoms in relation to cognitive and affective empathy in a non-ASD clinic-referred sample. Participants were 134 children aged 3 to 9 years (M=5.60; 79% boys) with oppositional defiant/conduct disorder, and their parents. Clinicians, teachers, and parents reported on dimensions of child behavior, and parental reports of family dysfunction and direct observations of parental warmth/responsiveness assessed quality of family relationships. Results from multiple regression analysis showed that, over and above the effects of child conduct problem severity and quality of family relationships, both ASD symptoms and CU traits were uniquely associated with deficits in cognitive empathy. Moreover, CU traits demonstrated an independent association with affective empathy, and this relationship was moderated by ASD symptoms. That is, there was a stronger negative association between CU traits and affective empathy at higher versus lower levels of ASD symptoms. These findings suggest including both CU traits and ASD-related social impairments in models delineating the atypical development of empathy in children with conduct problems. PMID:25015711

  20. Thermally conductive, electrically insulating and melt-processable polystyrene/boron nitride nanocomposites prepared by in situ reversible addition fragmentation chain transfer polymerization.

    PubMed

    Huang, Xingyi; Wang, Shen; Zhu, Ming; Yang, Ke; Jiang, Pingkai; Bando, Yoshio; Golberg, Dmitri; Zhi, Chunyi

    2015-01-01

    Thermally conductive and electrically insulating polymer/boron nitride (BN) nanocomposites are highly attractive for various applications in many thermal management fields. However, so far most of the preparation methods for polymer/BN nanocomposites have usually caused difficulties in the material post processing. Here, an in situ grafting approach is designed to fabricate thermally conductive, electrically insulating and post-melt processable polystyrene (PS)/BN nanosphere (BNNS) nanocomposites by initiating styrene (St) on the surface functionalized BNNSs via reversible addition fragmentation chain transfer polymerization. The nanocomposites exhibit significantly enhanced thermal conductivity. For example, at a St/BN feeding ratio of 5:1, an enhancement ratio of 1375% is achieved in comparison with pure PS. Moreover, the dielectric properties of the nanocomposites show a desirable weak dependence on frequency, and the dielectric loss tangent of the nanocomposites remains at a very low level. More importantly, the nanocomposites can be subjected to multiple melt processing to form different shapes. Our method can become a universal approach to prepare thermally conductive, electrically insulating and melt-processable polymer nanocomposites with diverse monomers and nanofillers. PMID:25493655

  1. Thermally conductive, electrically insulating and melt-processable polystyrene/boron nitride nanocomposites prepared by in situ reversible addition fragmentation chain transfer polymerization

    NASA Astrophysics Data System (ADS)

    Huang, Xingyi; Wang, Shen; Zhu, Ming; Yang, Ke; Jiang, Pingkai; Bando, Yoshio; Golberg, Dmitri; Zhi, Chunyi

    2015-01-01

    Thermally conductive and electrically insulating polymer/boron nitride (BN) nanocomposites are highly attractive for various applications in many thermal management fields. However, so far most of the preparation methods for polymer/BN nanocomposites have usually caused difficulties in the material post processing. Here, an in situ grafting approach is designed to fabricate thermally conductive, electrically insulating and post-melt processable polystyrene (PS)/BN nanosphere (BNNS) nanocomposites by initiating styrene (St) on the surface functionalized BNNSs via reversible addition fragmentation chain transfer polymerization. The nanocomposites exhibit significantly enhanced thermal conductivity. For example, at a St/BN feeding ratio of 5:1, an enhancement ratio of 1375% is achieved in comparison with pure PS. Moreover, the dielectric properties of the nanocomposites show a desirable weak dependence on frequency, and the dielectric loss tangent of the nanocomposites remains at a very low level. More importantly, the nanocomposites can be subjected to multiple melt processing to form different shapes. Our method can become a universal approach to prepare thermally conductive, electrically insulating and melt-processable polymer nanocomposites with diverse monomers and nanofillers.

  2. CMS Pixel Telescope Addition to T-980 Bent Crystal Collimation Experiment at the Tevatron

    SciTech Connect

    Rivera, Ryan; Annala, Jerry; Johnson, Todd; Kwan, Simon; Lundberg, Carl; Still, Dean; Prosser, Alan; Uplegger, Lorenzo; Zagel, Jim; Zvodaya, Viktoriya; /Fermilab

    2011-09-14

    An enhancement to the T-980 bent crystal collimation experiment at the Tevatron has been completed. The enhancement was the installation of a pixel telescope inside the vacuum-sealed beam pipe of the Tevatron. The telescope is comprised of six CMS PSI46 pixel plaquettes, arranged as three stations of horizontal and vertical planes, with the CAPTAN system for data acquisition and control. The purpose of the pixel telescope is to measure beam profiles produced by bent crystals under various conditions. The telescope electronics inside the beam pipe initially were not adequately shielded from the image current of the passing beams. A new shielding approach was devised and installed, which resolved the problem. The noise issues encountered and the mitigating techniques are presented herein, as well as some preliminary results from the telescope.

  3. EFFECT OF (Bi2O3)0.75(Y2O3)0.25 ADDITION ON MICROSTRUCTURES AND IONIC CONDUCTIVITIES OF CODOPED ZIRCONIA

    NASA Astrophysics Data System (ADS)

    Chou, Chen Chia; Huang, Chun Feng; Yeh, Tsung Her

    2012-09-01

    Variation of microstructures and ionic conductivities in (Bi2O3)0.75(Y2O3)0.25 (YSB) modified electrolyte of 8 mol% Y2O3 stabilized zirconia (8YSZ) and YSB modified codoped zirconia (ZrO2)0.92(Y2O3)0.075(MgO)0.005 (YSZM) is investigated in this work. The results demonstrated that a small amount of δ-YSB addition is effective in reducing the sintering temperature of 8YSZ from 1500 to 1200°C and promoting the densification rate of ceramics. Compared to 8YSZ electrolyte, it is interesting that a very limited amount of monoclinic ZrO2 was observed due to the MgO stabilizer in YSB modified codoped zirconia electrolyte. Besides, enhancement of ionic conductivity in δ-YSB modified codoped zirconia is evidently increased by 67% in comparison to the specimen of 8YSZ electrolyte.

  4. Deciphering transmissivity and hydraulic conductivity of the aquifer by vertical electrical sounding (VES) experiments in Northwest Bangladesh

    NASA Astrophysics Data System (ADS)

    Sattar, Golam Shabbir; Keramat, Mumnunul; Shahid, Shamsuddin

    2016-03-01

    The vertical electrical soundings (VESs) are carried out in 24 selective locations of Chapai-Nawabganj area of northwest Bangladesh to determine the transmissivity and hydraulic conductivity of the aquifer. Initially, the transmissivity and hydraulic conductivity are determined from the pumping data of nearby available production wells. Afterwards, the T and K are correlated with geoelectrical resistance and the total resistivity of the aquifer. The present study deciphers the functional analogous relations of the geoelectrical resistance with the transmissivity and the total resistivity with the hydraulic conductivity of the aquifer in northwest Bangladesh. It has been shown that the given equations provide reasonable values of transmissivity and hydraulic conductivity where pumping test information is unavailable. It can be expected that the aquifer properties viz. transmissivity and hydraulic conductivity of geologically similar area can be determined with the help of the obtained equations by conducting VES experiments.

  5. Students' Design of Experiments: An Inquiry Module on the Conduction of Heat

    ERIC Educational Resources Information Center

    Hatzikraniotis, E.; Kallery, M.; Molohidis, A.; Psillos, D.

    2010-01-01

    This article examines secondary students' design of experiments after engagement in an innovative and inquiry-oriented module on heat transfer. The module consists of an integration of hands-on experiments, simulated experiments and microscopic model simulations, includes a structured series of guided investigative tasks and was implemented for a…

  6. Summary and overview of the CYCLOPS P addition Lagrangian experiment in the Eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Krom, M. D.; Thingstad, T. F.; Brenner, S.; Carbo, P.; Drakopoulos, P.; Fileman, T. W.; Flaten, G. A. F.; Groom, S.; Herut, B.; Kitidis, V.; Kress, N.; Law, C. S.; Liddicoat, M. I.; Mantoura, R. F. C.; Pasternak, A.; Pitta, P.; Polychronaki, T.; Psarra, S.; Rassoulzadegan, F.; Skjoldal, E. F.; Spyres, G.; Tanaka, T.; Tselepides, A.; Wassmann, P.; Wexels Riser, C.; Woodward, E. M. S.; Zodiatis, G.; Zohary, T.

    2005-11-01

    CYCLOPS was a European Framework 5 program to further our understanding of phosphorus cycling in the Eastern Mediterranean. The core of CYCLOPS was a Lagrangian experiment in which buffered phosphoric acid was added to a <4×4 km patch of water together with SF 6 as the inert tracer. The patch was followed for nine days in total. Results obtained prior to the experiment showed that the system was typically ultra-oligotrophic and P-starved with DON:DOP, PON:POP and DIN:DIP all having ratios greatly in excess of 16:1 in surface waters. To our surprise, we found that although the added phosphate was rapidly taken up by the microbial biota, there was a small but significant decrease in chlorophyll a and no increase in primary production, together with an increase in heterotrophic bacterial activity, ciliate numbers and in the gut fullness and egg numbers in the zooplankton community. A microcosm experiment carried out using within-patch and out-of-patch water showed that the phytoplankton community were N and P co-limited while the bacteria and micrograzers were P-limited. Thus this system tends to N and P co-limitation of phytoplankton productivity in summer possibly caused by bioavailable DIN being converted into non-bioavailable forms of DON. On the basis of the data collected within the programme it was concluded that this behavior could be explained by three non-mutually exclusive processes described as (1) trophic by-pass in which the added phosphate gets directly to the grazing part of the predatory food chain from the heterotrophic bacteria bypassing the phytoplankton compartment phosphate, (2) trophic tunnelling in which phosphate is rapidly taken up by both phytoplankton and bacteria via rapid luxury consumption. This causes an immediate change in the phosphorus content but not the abundance of the prey organisms. The added P then "reappears" as responses at the predator level much more rapidly than expected, and (3) mixotrophic by-pass in which inorganic

  7. [Requirements for drug approval and additional benefits assessment: Regulatory aspects and experiences].

    PubMed

    Broich, K; Löbker, W; Schulte, A; Beinlich, P; Müller, T

    2016-04-01

    The early assessment of benefits of newly approved drugs with novel active substances or new applications, which came into force on 1 January 2011 still represents a challenge to all parties involved. This article highlights the definitions, regulatory requirements and interaction between drug marketing approval and early assessment of benefits in Germany. The constellation of an extensively harmonized European and even international drug authorization process with a predominantly national regulation of drug reimbursement situation inevitably causes friction, which could be markedly reduced through early joint advisory discussions during the planning phase for pivotal clinical trials. During the year 2015 the Federal Institute for Drugs and Medical Devices (BfArM) carried out 300 scientific advice procedures of which 34 were concerned with applications in the field of indications for the central nervous system (CNS). In comparison 98 advisory meetings were held by the Federal Joint Committee (G-BA) of which the BfArM provided advice in 12 instances and in 2 cases on CNS indications. Study design, endpoints and appropriate comparative therapies are the key issues in exchanges and discussions between the BfArM, the G‑BA and applicants. Under these aspects the BfArM and G‑BA promote an early and consistent involvement in early advice procedures regarding the prerequisites for drug approval and assessment of additional benefits. PMID:27003322

  8. Effects of biochar addition to soil on nitrogen fluxes in a winter wheat lysimeter experiment

    NASA Astrophysics Data System (ADS)

    Hüppi, Roman; Leifeld, Jens; Neftel, Albrecht; Conen, Franz; Six, Johan

    2014-05-01

    Biochar is a carbon-rich, porous residue from pyrolysis of biomass that potentially increases crop yields by reducing losses of nitrogen from soils and/or enhancing the uptake of applied fertiliser by the crops. Previous research is scarce about biochar's ability to increase wheat yields in temperate soils or how it changes nitrogen dynamics in the field. In a lysimeter system with two different soils (sandy/silt loam) nitrogen fluxes were traced by isotopic 15N enriched fertiliser to identify changes in nitrous oxide emissions, leaching and plant uptake after biochar addition. 20t/ha woodchip-waste biochar (pH=13) was applied to these soils in four lysimeters per soil type; the same number of lysimeters served as a control. The soils were cropped with winter wheat during the season 2012/2013. 170 kg-N/ha ammonium nitrate fertiliser with 10% 15N was applied in 3 events during the growing season and 15N concentrations where measured at different points in time in plant, soil, leachate and emitted nitrous oxide. After one year the lysimeter system showed no difference between biochar and control treatment in grain- and straw yield or nitrogen uptake. However biochar did reduce nitrous oxide emissions in the silt loam and losses of nitrate leaching in sandy loam. This study indicates potential reduction of nitrogen loss from cropland soil by biochar application but could not confirm increased yields in an intensive wheat production system.

  9. Diesel engine experiments with oxygen enrichment, water addition and lower-grade fuel

    SciTech Connect

    Sekar, R.R.; Marr, W.W.; Cole, R.L.; Marciniak, T.J. ); Schaus, J.E. )

    1990-01-01

    The concept of oxygen enriched air applied to reciprocating engines is getting renewed attention in the context of the progress made in the enrichment methods and the tougher emissions regulations imposed on diesel and gasoline engines. An experimental project was completed in which a direct injection diesel engine was tested with intake oxygen levels of 21% -- 35%. Since an earlier study indicated that it is necessary to use a cheaper fuel to make the concept economically attractive, a less refined fuel was included in the test series. Since a major objection to the use of oxygen enriched combustion air had been the increase in NO{sub x} emissions, a method must be found to reduce NO{sub x}. Introduction of water into the engine combustion process was included in the tests for this purpose. Fuel emulsification with water was the means used here even though other methods could also be used. The teat data indicated a large increase in engine power density, slight improvement in thermal efficiency, significant reductions in smoke and particulate emissions and NO{sub x} emissions controllable with the addition of water. 15 refs., 10 figs., 2 tabs.

  10. Nitrate removal in stream ecosystems measured by 15N addition experiments: 2. Denitrification

    SciTech Connect

    Mulholland, Patrick J; Hall, Robert; Sobota, Daniel; Dodds, Walter; Findlay, Stuart; Grimm, Nancy; Hamilton, Stephen; McDowell, William; O'Brien, Jon; Tank, Jennifer; Ashkenas, Linda; Cooper, Lee W; Dahm, Cliff; Gregory, Stanley; Johnson, Sherri; Meyer, Judy; Peterson, Bruce; Poole, Geoff; Valett, H. Maurice; Webster, Jackson; Arango, Clay; Beaulieu, Jake; Bernot, Melody; Burgin, Amy; Crenshaw, Chelsea; Helton, Ashley; Johnson, Laura; Niederlehner, Bobbie; Potter, Jody; Sheibley, Rich; Thomas, Suzanne

    2009-01-01

    We measured denitrification rates using a field {sup 15}N-NO{sub 3}{sup -} tracer-addition approach in a large, cross-site study of nitrate uptake in reference, agricultural, and suburban-urban streams. We measured denitrification rates in 49 of 72 streams studied. Uptake length due to denitrification (S{sub Wden}) ranged from 89 m to 184 km (median of 9050 m) and there were no significant differences among regions or land-use categories, likely because of the wide range of conditions within each region and land use. N{sub 2} production rates far exceeded N{sub 2}O production rates in all streams. The fraction of total NO{sub 3}{sup -} removal from water due to denitrification ranged from 0.5% to 100% among streams (median of 16%), and was related to NH{sub 4}{sup +} concentration and ecosystem respiration rate (ER). Multivariate approaches showed that the most important factors controlling S{sub Wden} were specific discharge (discharge/width) and NO{sub 3}{sup -} concentration (positive effects), and ER and transient storage zones (negative effects). The relationship between areal denitrification rate (U{sub den}) and NO{sub 3}{sup -} concentration indicated a partial saturation effect. A power function with an exponent of 0.5 described this relationship better than a Michaelis-Menten equation. Although U{sub den} increased with increasing NO{sub 3}{sup -} concentration, the efficiency of NO{sub 3}{sup -} removal from water via denitrification declined, resulting in a smaller proportion of streamwater NO{sub 3}{sup -} load removed over a given length of stream. Regional differences in stream denitrification rates were small relative to the proximate factors of NO{sub 3}{sup -} concentration and ecosystem respiration rate, and land use was an important but indirect control on denitrification in streams, primarily via its effect on NO{sub 3}{sup -} concentration.

  11. Nitrate removal in stream ecosystems measured by 15N addition experiments: Denitrification

    USGS Publications Warehouse

    Mulholland, P.J.; Hall, R.O., Jr.; Sobota, D.J.; Dodds, W.K.; Findlay, S.E.G.; Grimm, N. B.; Hamilton, S.K.; McDowell, W.H.; O'Brien, J. M.; Tank, J.L.; Ashkenas, L.R.; Cooper, L.W.; Dahm, Clifford N.; Gregory, S.V.; Johnson, S.L.; Meyer, J.L.; Peterson, B.J.; Poole, G.C.; Valett, H.M.; Webster, J.R.; Arango, C.P.; Beaulieu, J.J.; Bernot, M.J.; Burgin, A.J.; Crenshaw, C.L.; Helton, A.M.; Johnson, L.T.; Niederlehner, B.R.; Potter, J.D.; Sheibley, R.W.; Thomasn, S.M.

    2009-01-01

    We measured denitrification rates using a field 15N-NO- 3 tracer-addition approach in a large, cross-site study of nitrate uptake in reference, agricultural, and suburban-urban streams. We measured denitrification rates in 49 of 72 streams studied. Uptake length due to denitrification (SWden) ranged from 89 m to 184 km (median of 9050 m) and there were no significant differences among regions or land-use categories, likely because of the wide range of conditions within each region and land use. N2 production rates far exceeded N2O production rates in all streams. The fraction of total NO-3 removal from water due to denitrification ranged from 0.5% to 100% among streams (median of 16%), and was related to NHz 4 concentration and ecosystem respiration rate (ER). Multivariate approaches showed that the most important factors controlling SWden were specific discharge (discharge / width) and NO-3 concentration (positive effects), and ER and transient storage zones (negative effects). The relationship between areal denitrification rate (Uden) and NO- 3 concentration indicated a partial saturation effect. A power function with an exponent of 0.5 described this relationship better than a Michaelis-Menten equation. Although Uden increased with increasing NO- 3 concentration, the efficiency of NO-3 removal from water via denitrification declined, resulting in a smaller proportion of streamwater NO-3 load removed over a given length of stream. Regional differences in stream denitrification rates were small relative to the proximate factors of NO-3 concentration and ecosystem respiration rate, and land use was an important but indirect control on denitrification in streams, primarily via its effect on NO-3 concentration. ?? 2009.

  12. Electrical conductivity of Icelandic deep geothermal reservoirs: insight from HT-HP laboratory experiments

    NASA Astrophysics Data System (ADS)

    Nono, Franck; Gibert, Benoit; Loggia, Didier; Parat, Fleurice; Azais, Pierre; Cichy, Sarah

    2016-04-01

    Although the Icelandic geothermal system has been intensively investigated over the years, targeting increasingly deeper reservoirs (i.e. under supercritical conditions) requires a good knowledge of the behaviour of physical properties of the host rock in order to better interpret large scale geophysical observations. In particular, the interpretation of deep electrical soundings remains controversial as only few studies have investigated the influence of altered minerals and pore fluid properties on electrical properties of rocks at high temperature and pressure. In this study, we investigate the electrical conductivity of drilled samples from different Icelandic geothermal fields at elevated temperature, confining pressure and pore pressure conditions (100°C < T < 600°C, confining pressure up to 100 MPa and pore pressure up to 35 MPa). The investigated rocks are composed of hyaloclastites, dolerites and basalts taken from depths of about 800 m for the hyaloclastites, to almost 2500 m for the dolerites. They display different porosity structures, from vuggy and intra-granular to micro-cracked porosities, and have been hydrothermally alterated in the chlorite to amphibolite facies. Electrical conductivity measurements are first determined at ambient conditions as a function of pore fluid conductivity in order to establish their relationships with lithology and pore space topology, prior to the high pressure and temperature measurements. Cementation factor varies from 1.5 for the dolerites to 2.83 for the basalt, reflecting changes in the shape of the conductive channels. The surface conductivities, measured at very low fluid conductivity, increases with the porosity and is correlated with the cation exchange capacity. At high pressure and temperature, we used the two guard-ring electrodes system. Measurements have been performed in dry and saturated conditions as a function of temperature and pore pressure. The supercritical conditions have been investigated and

  13. Effect of phosphorus additions on the sintering and transport properties of proton conducting BaZr0.85Y0.15O3-δ

    NASA Astrophysics Data System (ADS)

    Soares, H. S.; Zhang, X.; Antunes, I.; Frade, J. R.; Mather, G. C.; Fagg, D. P.

    2012-07-01

    The influence of phosphorous additions on the sintering and electrical transport properties of the proton-conducting perovskite BaZr0.85Y0.15O3-δ (BZY) has been studied with a view to the use of phosphates as typical dispersants for the formation of stabilised solid suspensions or as possible sintering aids. P2O5 additions, (1-x)BZY·xP2O5, monotonously promote densification in the intermediate compositional range 0.04≤x≤0.08. Nonetheless, BZY reacts with phosphorous forming the phase Ba3(PO4)2 at temperatures as low as 600 °C. The associated loss of Ba from the perovskite, leads to a decrease in the perovskite lattice parameter, the formation of yttria-based impurity phases and impaired grain growth. Such reaction has an extremely detrimental effect on bulk and grain boundary conductivities. It is, therefore, vital that the current results are taken into account by the protonics community when attempting to prepare the stabilised solid suspensions of BZY nanopowders required for thin ceramic applications. Alternative dispersants to phosphate esters must be found.

  14. The Lattice and Thermal Radiation Conductivity of Thermal Barrier Coatings: Models and Experiments

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Spuckler, Charles M.

    2010-01-01

    The lattice and radiation conductivity of ZrO2-Y2O3 thermal barrier coatings was evaluated using a laser heat flux approach. A diffusion model has been established to correlate the coating apparent thermal conductivity to the lattice and radiation conductivity. The radiation conductivity component can be expressed as a function of temperature, coating material scattering, and absorption properties. High temperature scattering and absorption of the coating systems can be also derived based on the testing results using the modeling approach. A comparison has been made for the gray and nongray coating models in the plasma-sprayed thermal barrier coatings. The model prediction is found to have a good agreement with experimental observations.

  15. Using Coupled Mesoscale Experiments and Simulations to Investigate High Burn-Up Oxide Fuel Thermal Conductivity

    NASA Astrophysics Data System (ADS)

    Teague, Melissa C.; Fromm, Bradley S.; Tonks, Michael R.; Field, David P.

    2014-12-01

    Nuclear energy is a mature technology with a small carbon footprint. However, work is needed to make current reactor technology more accident tolerant and to allow reactor fuel to be burned in a reactor for longer periods of time. Optimizing the reactor fuel performance is essentially a materials science problem. The current understanding of fuel microstructure have been limited by the difficulty in studying the structure and chemistry of irradiated fuel samples at the mesoscale. Here, we take advantage of recent advances in experimental capabilities to characterize the microstructure in 3D of irradiated mixed oxide (MOX) fuel taken from two radial positions in the fuel pellet. We also reconstruct these microstructures using Idaho National Laboratory's MARMOT code and calculate the impact of microstructure heterogeneities on the effective thermal conductivity using mesoscale heat conduction simulations. The thermal conductivities of both samples are higher than the bulk MOX thermal conductivity because of the formation of metallic precipitates and because we do not currently consider phonon scattering due to defects smaller than the experimental resolution. We also used the results to investigate the accuracy of simple thermal conductivity approximations and equations to convert 2D thermal conductivities to 3D. It was found that these approximations struggle to predict the complex thermal transport interactions between metal precipitates and voids.

  16. Microstructure and Electrical Conductivity of ZnO Addition on the Properties of (Bi0.92Ho0.03Er0.05)2O3

    NASA Astrophysics Data System (ADS)

    Ermiş, İ.; Çorumlu, V.; Sertkol, M.; Öztürk, M.; Kaleli, M.; Çetin, A.; Turemiş, M.; Arı, M.

    2016-07-01

    The solid electrolyte is one of the most important components for a solid oxide fuel cell (SOFC). The various divalent or trivalent metal ion-doped bismuth-based materials exhibit good ionic conductivity. Therefore, these materials are used as electrolytes in the SOFC. In this paper, the samples of (Bi0.92-x Ho0.03Er0.05)2O3 + (ZnO) x solutions with a 0 ≤ x ≤ 0.2 molar ratio are synthesized by the solid state reaction method. The detailed structural and electrical characterizations are investigated by using x-ray diffraction (XRD), alternating current electrochemical impedance spectroscopy, and scanning electron microscopy (SEM). The XRD patterns of all samples are indexed on a monoclinic symmetry with a P21/c space group. In addition, the rietveld parameters are determined by using the FullProf software program. The impedance measurements of the samples are obtained at the 1 Hz to 20 MHz frequency range. The impedance value of the pellets increases with temperature. Based on the impedance results, it is found that the contribution of grain (bulk) is more than a grain boundary in terms of conductivity, which permits the attribution of a grain boundary. The ionic conductivity decreases with an increasing amount of Zn contribution. The value of highest electrical conductivity among all samples is calculated as 0.358 S cm-1 at 800°C for undoped (Bi0.92Ho0.03Er0.05)2O3.

  17. Exploring the Experiences of Faculty-Led Teams in Conducting Action Research

    ERIC Educational Resources Information Center

    Zhang, Qi; Amundsen, Cheryl

    2015-01-01

    Action research has been suggested as a useful way to support university faculty to improve teaching and learning. However, there seems to be little knowledge about how faculty (and those who work with them) experience the process of doing action research. In order to explore team members' in-depth experience about what they learned and how they…

  18. Sodium Concentration Measurement during Hemodialysis through Ion-Exchange Resin and Conductivity Measure Approach: In Vitro Experiments

    PubMed Central

    Tura, Andrea; Sbrignadello, Stefano; Mambelli, Emanuele; Ravazzani, Paolo; Santoro, Antonio; Pacini, Giovanni

    2013-01-01

    Sodium measurement during hemodialysis treatment is important to preserve the patient from clinical events related to hypo- or hyper-natremia Usually, sodium measurement is performed through laboratory equipment which is typically expensive, and requires manual intervention. We propose a new method, based on conductivity measurement after treatment of dialysate solution through ion-exchange resin. To test this method, we performed in vitro experiments. We prepared 40 ml sodium chloride (NaCl) samples at 280, 140, 70, 35, 17.5, 8.75, 4.375 mEq/l, and some “mixed samples”, i.e., with added potassium chloride (KCl) at different concentrations (4.375-17.5 mEq/l), to simulate the confounding factors in a conductivity-based sodium measurement. We measured the conductivity of all samples. Afterwards, each sample was treated for 1 min with 1 g of Dowex G-26 resin, and conductivity was measured again. On average, the difference in the conductivity between mixed samples and corresponding pure NaCl samples (at the same NaCl concentration) was 20.9%. After treatment with the exchange resin, it was 14.7%, i.e., 42% lower. Similar experiments were performed with calcium chloride and magnesium chloride as confounding factors, with similar results. We also performed some experiments on actual dialysate solution during hemodialysis sessions in 15 patients, and found that the correlation between conductivity measures and sodium concentration improved after resin treatment (R=0.839 before treatment, R=0.924 after treatment, P<0.0001). We conclude that ion-exchange resin treatment coupled with conductivity measures may improve the measurement of sodium compared to conductivity measures alone, and may become a possible simple approach for continuous and automatic sodium measurement during hemodialysis. PMID:23844253

  19. Numerical experiment of thermal conductivity in two-dimensional Yukawa liquids

    SciTech Connect

    Shahzad, Aamir; He, Mao-Gang

    2015-12-15

    A newly improved homogenous nonequilibrium molecular dynamics simulation (HNEMDS) method, proposed by the Evans, has been used to compute the thermal conductivity of two-dimensional (2D) strongly coupled complex (dusty) plasma liquids (SCCDPLs), for the first time. The effects of equilibrium external field strength along with different system sizes and plasma states (Γ, κ) on the thermal conductivity of SCCDPLs have been calculated using an enhanced HNEMDS method. A simple analytical temperature representation of Yukawa 2D thermal conductivity with appropriate normalized frequencies (plasma and Einstein) has also been calculated. The new HNEMDS algorithm shows that the present method provides more accurate results with fast convergence and small size effects over a wide range of plasma states. The presented thermal conductivity obtained from HNEMDS method is found to be in very good agreement with that obtained through the previously known numerical simulations and experimental results for 2D Yukawa liquids (SCCDPLs) and with the three-dimensional nonequilibrium molecular dynamics simulation (MDS) and equilibrium MDS calculations. It is shown that the HNEMDS algorithm is a powerful tool, making the calculations very efficient and can be used to predict the thermal conductivity in 2D Yukawa liquid systems.

  20. Using Satellite Technology to Increase Professional Communications Among Teachers: a Report of Experiments Conducted by the National Education Association.

    ERIC Educational Resources Information Center

    National Education Association, Washington, DC. Div. of Instruction and Professional Development.

    The National Education Association (NEA) in conjunction with the National Aeronautics and Space Administration, the National Library of Medicine, The Alaska Broadcasting Commission, and the Pacific PEACESAT Network, conducted four satellite experiments designed to improve professional communication among teachers. These programs were the Satellite…

  1. Effect of Two-Tier Diagnostic Tests on Promoting Learners' Conceptual Understanding of Variables in Conducting Scientific Experiments

    ERIC Educational Resources Information Center

    Çil, Emine

    2015-01-01

    Taking a test generally improves the retention of the material tested. This is a phenomenon commonly referred to as testing effect. The present research investigated whether two-tier diagnostic tests promoted student teachers' conceptual understanding of variables in conducting scientific experiments, which is a scientific process skill. In this…

  2. A Comparison of Supervised Occupational Experience Programs Conducted by Males and Females in Wyoming. A Report of Research.

    ERIC Educational Resources Information Center

    Reynolds, Carl L.

    A study was conducted in Wyoming to determine the scope and economic value of supervised occupational experience programs (SOEPs) in vocational agriculture. The study tried to determine the level of participation and success realized by females engaged in SOEP activities, and to find out to what degree males and females engage in balanced SOEPs,…

  3. W-doped anatase TiO{sub 2} transparent conductive oxide films: Theory and experiment

    SciTech Connect

    Chen Deming; Xu Gang; Miao Lei; Chen Lihua; Nakao, Setsuo; Jin, Ping

    2010-03-15

    W-doped anatase TiO{sub 2} films were deposited on glass substrate by magnetron cosputtering. The minimum resistivity, 1.5x10{sup -2} {Omega} cm, for Ti{sub 1-x}W{sub x}O{sub 2} film (x=0.063) was obtained. X-ray photoelectron spectroscopy analysis shows W incorporated in the Ti lattice position is mostly in the W{sup 6+} state. Theoretical calculations based upon the density-functional theory were applied to analyze the electronic structure and conducting mechanism. The strong hybridization of Ti 3d states with W 5d states is the dominate factor to cause the shifting in Fermi level into conduction band. Our results suggest that tungsten is a favorable dopant to form TiO{sub 2}-based transparent conducting oxide materials.

  4. Theme: The Role of the Teacher in Conducting Supervised Agricultural Experience Programs.

    ERIC Educational Resources Information Center

    Agricultural Education Magazine, 2003

    2003-01-01

    Contains 13 theme articles on the role of teachers in supervised agricultural experience (SAE) programs that offer suggestions, ideas, and practices to advance the implementation of SAE programs. (JOW)

  5. Human Nutrition Research Conducted at State Agricultural Experiment Stations and 1890/Tuskegee Agricultural Research Programs.

    ERIC Educational Resources Information Center

    Driskell, Judy A.; Myers, John R.

    1989-01-01

    Cooperative State Research Service-administered and state-appropriated State Agriculture Experiment Station funds for human nutrition research increased about two-fold from FY70-FY86, while the percentage of budget expended for this research decreased. (JOW)

  6. A system for conducting igneous petrology experiments under controlled redox conditions in reduced gravity

    NASA Technical Reports Server (NTRS)

    Williams, R. J.

    1986-01-01

    The Space Shuttle and the planned Space Station will permit experimentation under conditions of reduced gravitational acceleration offering experimental petrologists the opportunity to study crystal growth, element distribution, and phase chemistry. In particular the confounding effects of macro and micro scale buoyancy-induced convection and crystal settling or floatation can be greatly reduced over those observed in experiments in the terrestrial laboratory. Also, for experiments in which detailed replication of the environment is important, the access to reduced gravity will permit a more complete simulation of processes that may have occurred on asteroids or in free space. A technique that was developed to control, measure, and manipulate oxygen fugacites with small quantities of gas which are recirculated over the sample is described. This system should be adaptable to reduced gravity space experiments requiring redox control. Experiments done conventionally and those done using this technique yield identical results done in a 1-g field.

  7. Sub-Kelvin Thermal Conductivity and Radioactivity of Some Useful Materials in Low Background Cryogenic Experiments

    NASA Astrophysics Data System (ADS)

    Kellaris, N.; Daal, M.; Epland, M.; Pepin, M.; Kamaev, O.; Cushman, P.; Kramer, E.; Sadoulet, B.; Mirabolfathi, N.; Golwala, S.; Runyan, M.

    2014-08-01

    We present measurements of the thermal conductivity between 0.05 and 1 K, and radioactive contamination levels, for some thermally isolating materials. TIMET Ti 15-3-3-3, Mersen grade 2020 graphite, Vespel SP-1, Vespel SP-22, Vespel SCP-5000, Vespel SCP-5050, Graphlite CFRP, and a Kapton/epoxy composite are all investigated. Thermal conductivities were measured using a single-heater longitudinal heat flow method. Material radioactivity was determined for the materials at a low background counting facility using a high-purity gamma detector and GEANT4 Monte Carlo simulations.

  8. MISSE PEACE Polymers: An International Space Station Environmental Exposure Experiment Being Conducted

    NASA Technical Reports Server (NTRS)

    deGroh, Kim K.; Banks, Bruce A.; Hammerstrom, Anne; Youngstrom, Erica; Kaminski, Carolyn; Marx, Laura; Fine, Elizabeth; Gummow, Jonathan D.; Wright, Douglas

    2002-01-01

    As part of the Materials International Space Station Experiment (MISSE), 41 different polymers are being exposed for approximately 1 1/2 years to the low-Earth-orbit (LEO) environment on the exterior of the International Space Station. MISSE is a materials flight experiment sponsored by the Air Force Research Lab/Materials Lab and NASA, and is the first external experiment on the space station. A similar set of 41 polymers will be flown as part of the Polymer Erosion and Contamination Experiment (PEACE) a shuttle flight experiment that is being developed at the NASA Glenn Research Center collaboratively with the Hathaway Brown School for girls. Therefore, these 41 polymers are collectively called the MISSE PEACE Polymers. The purpose of the MISSE PEACE Polymers experiment is to determine how durable polymers are in the LEO space environment where spacecraft, such as the space station, orbit. Polymers are commonly used as spacecraft materials because of their desirable properties such as good flexibility, low density, and certain electrical properties or optical properties (such as a low solar absorptance and high thermal emittance). Two examples of the use of polymers on the exterior of spacecraft exposed to the space environment include metalized Teflon FEP (fluorinated ethylene propylene, DuPont) thermal control materials on the Hubble Space Telescope, and polyimide Kapton (DuPont) solar array blankets.

  9. Portable Conduction Velocity Experiments Using Earthworms for the College and High School Neuroscience Teaching Laboratory

    ERIC Educational Resources Information Center

    Shannon, Kyle M.; Gage, Gregory J.; Jankovic, Aleksandra; Wilson, W. Jeffrey; Marzullo, Timothy C.

    2014-01-01

    The earthworm is ideal for studying action potential conduction velocity in a classroom setting, as its simple linear anatomy allows easy axon length measurements and the worm's sparse coding allows single action potentials to be easily identified. The earthworm has two giant fiber systems (lateral and medial) with different conduction…

  10. Designing and Conducting Strong Quasi-Experiments in Education. Version 2

    ERIC Educational Resources Information Center

    Scher, Lauren; Kisker, Ellen; Dynarski, Mark

    2015-01-01

    The purpose of this paper is to describe best practices in designing and implementing strong quasi-experimental designs (QED) when assessing the effectiveness of policies, programs or practices. The paper first discusses the issues researchers face when choosing to conduct a QED, as opposed to a more rigorous randomized controlled trial design.…

  11. A Simple Rate Law Experiment Using a Custom-Built Isothermal Heat Conduction Calorimeter

    ERIC Educational Resources Information Center

    Wadso, Lars; Li, Xi.

    2008-01-01

    Most processes (whether physical, chemical, or biological) produce or consume heat: measuring thermal power (the heat production rate) is therefore a typical method of studying processes. Here we describe the design of a simple isothermal heat conduction calorimeter built for use in teaching; we also provide an example of its use in simultaneously…

  12. Reinforcing Concepts of Transient Heat Conduction and Convection with Simple Experiments and COMSOL Simulations

    ERIC Educational Resources Information Center

    Mendez, Sergio; AungYong, Lisa

    2014-01-01

    To help students make the connection between the concepts of heat conduction and convection to real-world phenomenon, we developed a combined experimental and computational module that can be incorporated into lecture or lab courses. The experimental system we present requires materials and apparatus that are readily accessible, and the procedure…

  13. EVALUATION OF THERMAL CONDUCTIVITY OF INSTALLED-IN-PLACE POLYURETHANE FOAM INSULATION BY EXPERIMENT AND ANALYSIS

    SciTech Connect

    Smith, A; Bruce Hardy, B; Kurt Eberl, K; Nick Gupta, N

    2007-12-05

    In the thermal analysis of the 9977 package, it was found that calculated temperatures, determined using a typical thermal analysis code, did not match those measured in the experimental apparatus. The analysis indicated that the thermal resistance of the overpack in the experimental apparatus was less than that expected, based on manufacturer's reported value of thermal conductivity. To resolve this question, the thermal conductivity of the installed foam was evaluated from the experimental results, using a simplified analysis. This study confirmed that the thermal resistance of the experimental apparatus was lower than that which would result from the manufacturer's published values for thermal conductivity of the foam insulation. The test package was sectioned to obtain samples for measurement of material properties. In the course of the destructive examination a large uninsulated region was found at the bottom of the package, which accounted for the anomalous results. Subsequent measurement of thermal conductivity confirmed the manufacturer's published values. The study provides useful insight into the use of simplified, scoping calculations for evaluation of thermal performance of packages.

  14. 77 FR 30238 - Living History Flight Experience (LHFE)-Exemptions for Passenger Carrying Operations Conducted...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-22

    ... complete Privacy Act Statement may be reviewed in the Federal Register published on April 11, 2000 (65 FR... Conducted for Compensation and Hire in Other Than Standard Category Aircraft (71 FR 15087). However, the FAA... of accommodating Word and PowerPoint presentations from a compact disk (CD) or USB memory...

  15. The NASA Real Time Mission Monitor - A Situational Awareness Tool for Conducting Tropical Cyclone Field Experiments

    NASA Technical Reports Server (NTRS)

    Goodman, Michael; Blakeslee, Richard; Hall, John; Parker, Philip; He, Yubin

    2008-01-01

    The NASA Real Time Mission Monitor (RTMM) is a situational awareness tool that integrates satellite, aircraft state information, airborne and surface instruments, and weather state data in to a single visualization package for real time field experiment management. RTMM optimizes science and logistic decision-making during field experiments by presenting timely data and graphics to the users to improve real time situational awareness of the experiment's assets. The RTMM is proven in the field as it supported program managers, scientists, and aircraft personnel during the NASA African Monsoon Multidisciplinary Analyses (investigated African easterly waves and Tropical Storm Debby and Helene) during August-September 2006 in Cape Verde, the Tropical Composition, Cloud and Climate Coupling experiment during July-August 2007 in Costa Rica, and the Hurricane Aerosonde mission into Hurricane Noel in 2-3 November 2007. The integration and delivery of this information is made possible through data acquisition systems, network communication links, and network server resources built and managed by collaborators at NASA Marshall Space Flight Center (MSFC) and Dryden Flight Research Center (DFRC). RTMM is evolving towards a more flexible and dynamic combination of sensor ingest, network computing, and decision-making activities through the use of a service oriented architecture based on community standards and protocols. Each field experiment presents unique challenges and opportunities for advancing the functionality of RTMM. A description of RTMM, the missions it has supported, and its new features that are under development will be presented.

  16. A system for conducting igneous petrology experiments under controlled redox conditions in reduced gravity

    NASA Technical Reports Server (NTRS)

    Williams, Richard J.

    1987-01-01

    The Space Shuttle and the planned Space Station will permit experimentation under conditions of reduced gravitational acceleration offering experimental petrologists the opportunity to study crystal growth, element distribution, and phase chemistry. In particular the confounding effects of macro and micro scale buoyancy-induced convection and crystal settling or flotation can be greatly reduced over those observed in experiments in the terrestrial laboratory. Also, for experiments in which detailed replication of the environment is important, the access to reduced gravity will permit a more complete simulation of processes that may have occurred on asteroids or in free space. A technique that was developed to control, measure, and manipulate oxygen fugacities with small quantities of gas which are recirculated over the sample. This system could be adaptable to reduced gravity space experiments requiring redox control.

  17. Summary of recent experiments on focusing of target-normal-sheath-accelerated proton beam with a stack of conducting foils

    SciTech Connect

    Ni, P. A.; Alexander, N.; Barnard, J. J.; Lund, S. M.

    2014-05-15

    We present a summary of recent experiments on focusing of laser target-normal-sheath-accelerated (TNSA) proton beam with a stack of thin conducting foils. The experiments were performed using the Phelix laser (GSI-Darmstadt) and the Titan laser, Lawrence Livermore National Laboratory. The phenomena consistent with self-collimation (or weak self-focusing) of TNSA protons were experimentally observed for the first time at the Phelix laser user facility, in a specially engineered structure ('lens') consisting of a stack of 300 thin aluminum foils separated by 50 μm vacuum gaps. Follow up experiments using the Titan laser obtained results consistent with the collimation/focusing observed in the initial experiments using the Phelix. The Titan experiments employed improved, 25 μm- and 50 μm-gap targets and the new fine mesh diagnostic. All the experiments were carried out in a “passive environment,” i.e., no external fields were applied, and no neutralization plasma or injection of secondary charged particles was imposed. A plausible interpretation of the observed phenomena is that the combination of magnetic self-pinch forces generated by the beam current together with the simultaneous reduction of the repulsive electrostatic forces due to the conducting foils inhibits radial expansion of the beam.

  18. ESA successfully conducts experiment in Advanced Space Robotics on Japanese satellite

    NASA Astrophysics Data System (ADS)

    1999-04-01

    ETS-VII is the latest in NASDA's series of engineering test satellites. It is dedicated to the in-orbit assessment and demonstration of novel technologies in rendez-vous / docking and space robotics. ETS-VII is in fact a pair of satellites, a larger chaser and a smaller target satellite which can be released for the rendez-vous and docking experiments. The larger satellite carries a robot arm with a stretched length of about 2 m, and a set of experimentation equipment to test the robot's capabilities : a task board on which typical robot manipulation activities can be performed and measured, an Orbital Replacement Unit (ORU) to be removed and reinstalled, a truss structure to be erected, an antenna assembly mechanism to be actuated and an advanced robot hand. The ESA experiments concern advanced schemes for planning, commanding, controlling and monitoring the activities of a space robot arm system. One set of experiments tests an operational mode called "interactive autonomy", whereby the robot motions are split into typical "tasks" of medium complexity. Ground operators can interact with the tasks (parameterising, commanding, rescheduling, monitoring, interrupting them as needed), relying on the fact that each task will be autonomously executed using appropriate sensor-based control loops (it having been programmed and extensively verified in advance by simulation). This significantly reduces the amount of data traffic over the spacelink - in fact, ETS-VII offers only a few short communications windows per day. Data from ESA experiments will be used to assess the performance of tasks executed with "interactive autonomy" compared with the more traditional telemanipulation at lower control levels. The second group of experiments concerns vision-based robot control. Using the Japanese-provided on-board vision system (which includes one hand camera and one scene-overview camera), it has been demonstrated that reliable automatic object localisation and grasping can be

  19. Laser patterning of transparent conductive metal nanowire coatings: simulation and experiment.

    PubMed

    Henley, Simon J; Cann, Maria; Jurewicz, Izabela; Dalton, Alan; Milne, David

    2014-01-21

    Transparent and electrically conductive metal nanowire networks are possible replacements for costly indium tin oxide (ITO) films in many optoelectronic devices. ITO films are regularly patterned using pulsed lasers so similar technologies could be used for nanowire coatings to define electrode structures. Here, the effects of laser irradiation on conducting silver nanowire coatings are simulated and then investigated experimentally for networks formed by spray deposition onto transparent substrates. The ablation threshold fluence is found experimentally for such nanowire networks and is then related to film thickness. An effective model using finite-element heat transfer analysis is examined to look at energy dissipation through these nanowire networks and used to understand mechanisms at play in the laser-material interactions. It is demonstrated that the three-dimensional nature of these coatings and the relative ratios of the rates of lateral to vertical heat diffusion are important controlling parameter affecting the ablation threshold. PMID:24287486

  20. What Knowledge of Responsible Conduct of Research Do Undergraduates Bring to Their Undergraduate Research Experiences?

    ERIC Educational Resources Information Center

    Mabrouk, Patricia Ann

    2016-01-01

    Over a three-year period, chemistry and engineering students participating in six Research Experience for Undergraduates (REU) programs were surveyed before and after participating in a research ethics training workshop. The goal was to learn what undergraduate students already knew about key concepts in research ethics at the start of their…

  1. A Laboratory Experiment, Based on the Maillard Reaction, Conducted as a Project in Introductory Statistics

    ERIC Educational Resources Information Center

    Kravchuk, Olena; Elliott, Antony; Bhandari, Bhesh

    2005-01-01

    A simple laboratory experiment, based on the Maillard reaction, served as a project in Introductory Statistics for undergraduates in Food Science and Technology. By using the principles of randomization and replication and reflecting on the sources of variation in the experimental data, students reinforced the statistical concepts and techniques…

  2. An Examination of the Benefits, Limitations, and Challenges of Conducting Randomized Experiments with Principals

    ERIC Educational Resources Information Center

    Camburn, Eric M.; Goldring, Ellen; Sebastian, James; May, Henry; Huff, Jason

    2016-01-01

    Purpose: The past decade has seen considerable debate about how to best evaluate the efficacy of educational improvement initiatives, and members of the educational leadership research community have entered the debate with great energy. Throughout this debate, the use of randomized experiments has been a particularly contentious subject. This…

  3. Soil Science self-learning based on the design and conduction of experiments

    NASA Astrophysics Data System (ADS)

    Jordán, A.; Bárcenas-Moreno, G.; Zavala, L. M.

    2012-04-01

    This paper presents an experience for introducing the methodology of project-based learning (PBL) in the area of Soil Science in the University of Sevilla (Spain). Currently, teachers try to enhance practical experience of university students in a complementary manner to theoretical knowledge. However, many times this is a difficult process. Practice is an important part of personal work in the vast majority of subjects that degree students receive, since the implementation of the EHEA. In most cases, these experiences are presented as partial small experiments or projects, assigned to the area-specific knowledge agenda. Certain sciences, such as Soil Science, however, require synthesis and integration capabilities of previous knowledge. It is therefore necessary to develop practical programs that address the student not only to the performance of laboratory determinations, but to the formulation of hypotheses, experimental design and problem solving, whether in groups or individually, situated in a wide context and allowing students to make connections with other areas of knowledge. This project involves the development of teamwork experiments, for the study real cases and problems and making decisions in the field of Soil Science. The results of the experimental work were publicly exposed as posters and oral presentations and were discussed during a mini-congress open to students and a general audience. The open and dynamic nature of the project substantially improves student motivation, which adds value to our project. Due to the multidisciplinary character of Soil Science it is relatively easy to propose projects of some complexity, and therefore, provides good conditions for introducing the PBL methodology. The teacher's role is also important and is not limited to observe or qualify the students, but it is a catalyst for learning. It is important that teacher give the leadership of the process and make the students themselves feel the protagonists of the

  4. Nerves, alcohol and drugs, the Adrian-Kato controversy on nervous conduction: deep insights from a "wrong" experiment?

    PubMed

    Piccolino, Marco

    2003-12-01

    Edgar Douglas Adrian, a dominating figure of 20th century electrophysiology, published in 1912 a study on the effects of the conduction block induced by application of alcohol vapours to small segments of nerves from which he derived the conclusion that nerve signals regenerate along the nerve fibre during the conduction process. This conclusion was based on results of experiments in which the time required to produce a conduction block was found to decrease as the length of the nerve segment treated was increased. These results could not be confirmed when similar experiments were performed about 10 years later by Gen'ichi Kato, a leading figure of Japanese physiology and founder of one of the great schools of Japanese electrophysiology. Directly or indirectly, the Adrian-Kato controversy was at the inception of two of the most important advancements of 20th century neurophysiology: the elucidation of the mechanism of nervous conduction in squid giant axon by Hodgkin and Huxley and the discovery of the saltatory conduction in myelinated nerve fibres by Tasaki, Takeuchi, Huxley and Stämpfli. This controversy is also interesting for its epistemological aspects, which is important now to re-evaluate. PMID:14629928

  5. Discipline report on thermal analyses of M551, M552, and M553 experiments. [on gravity and heat conduction

    NASA Technical Reports Server (NTRS)

    Muraki, T.; Masubuchi, K.

    1974-01-01

    Reduced gravity does not significantly affect the thermal histories in the M551 specimen, even if molten metal flow pattern is different from that in terrestrial conditions. Thermal histories corresponding to terrestrial experimental conditions were calculated by use of the computer programs. Heat conduction through brazing alloy (M552 experiment) is improved in the Skylab conditions, because of the increased extent, rate and uniformity of braze spreading in space. Effects of reduced gravity on heat flow in the M553 specimen are insignificant, because convection effects appear instantaneously and conduction is a governing factor on the heat flow.

  6. Measurement of soil and rock fractural hydraulic conductivities using falling head infiltration experiment of single-ring permeameter

    NASA Astrophysics Data System (ADS)

    Chen, X.; Zhang, Z. C.; Shi, P.; Cheng, Q. B.

    2012-04-01

    Southwest China Karst is a fragile area for ecological system because of thin soil and underlying rock fracures. Soil and rock fractural hydraulic conductivities in this area determine infiltration, runoff and water retaining in soil and rock fractures for plant utilization. Determination of soil and rock fractural hydraulic conductivities is very tough due to strong heterogeneous. In this paper, we designed a single-ring permeameter to measure the hydraulic conductivities based on falling head infiltration experiment. The experiments were conducted in two karst areas in southwest China: a hillslope in Huanjiang County, northwest Guangxi for measuring soil hydraulic conductivities and a profile at the small catchment of Chenqi in the Puding basin of Guizhou for measuring fractural hydraulic conductivities. The results show that surface soil hydraulic conductivity is 2.386×10-4 m/s, much larger than 2.004×10-5 m/s for the soil at 30cm depth. Soil hydraulic conductivities are generally increased from the bottom to the top along the hillslope, and this increase is particularly significant for the soil at 30cm depth. The fractural hydraulic conductivities were determined for the limestone profile with three fractures crossing in vertical and horizontal directions. The effective fractural aperture was determined according to calibration of water head variations of the ponded water in the single ring permeameter, which can be simulated by a numerical model based on Navier-Stokes equations and measured with an automatic observation equipment. The hydraulic conductivities were then estimated in terms of the cubic law equation. The estimated effective fractural aperture is 0.25mm for the horizontal fracture, and 0.25 and 0.5mm for the two vertical fractures crossing the horizontal in the right and left sides, respectively. The corresponding hydraulic conductivity is 0.051 m/s for the horizontal fracture and 0.051 and 0.204m/s for the two vertical fractures in the right

  7. [The infectious diseases experiments conducted on human guinea pigs by Nazis in concentration camps].

    PubMed

    Sabbatani, Sergio

    2013-06-01

    The author systematically examined all available publications and web documents, with regard to scientifically documented experiments carried out by Nazi physicians in their concentration camps during World War II. This research focused on human experiments dealing with: malaria, tuberculosis, petechial typhus, viral hepatitis, and those regarding sulphonamides as antimicrobial agents. The concentration camps involved by experimental programmes on human guinea pigs were: Natzweiler Struthof, Dachau, Mauthausen, Buchenwald, Neuengamme, Ravensbrück, Sachsenhausen and Auschwitz. Overall, around 7,200 deported prisoners went to their deaths during or because of these experiments (also considering human trials other than previously quoted ones). At the end of the war several physicians were charged with war crimes in two trials (Nuremberg and Dachau), and those found guilty were sentenced to death, or years of imprisonment. Some of them, including the notorious Josef Mengele, succeeded in escaping capture and being brought to justice. Thanks to these trials, partial light has been shed on these crimes, which not infrequently had children as designated victims, selected with excruciating cruelty in special segregation sections. The SS was the key structure which ensured maximum efficiency for these experimental programmes, from both logistic planning through to an operative control system carried out in concentration camps, and thanks to an autonomous, dedicated medical structure, which included a rigid hierarchy of physicians directly dependent on the head of SS forces (Reichsführer), i.e. Dr. Heinrich Himmler. Moreover, it is worth noting that also physicians who were not part of the SS corps collaborated in the above experiments on human guinea pigs: these included military personnel belonging to the Wehrmacht, academic physicians from German universities, and researchers who worked in some German pharmaceutical industries, such as IG Farben, Bayer and Boehring

  8. STS-55 MS3 Harris and Payload Specialist Schlegel conduct Anthrorack experiment

    NASA Technical Reports Server (NTRS)

    1993-01-01

    STS-55 German Payload Specialist 2 Hans Schlegel breathes into Rack 9 Anthrorack (AR) (Human Physiology Laboratory) device for Pulmonary Perfusion and Ventilation During Rest and Exercise experiment while working inside the Spacelab Deutsche 2 (SL-D2) science module aboard the Earth-orbiting Columbia, Orbiter Vehicle (OV) 102. In the background, Mission Specialist 3 (MS3) Bernard A. Harris, Jr monitors his activity.

  9. Growth and Morphology of Supercritical Fluids, a Fluid Physics Experiment Conducted on Mir, Complete

    NASA Technical Reports Server (NTRS)

    Wilkinson, R. Allen

    2001-01-01

    The Growth and Morphology of Supercritical Fluids (GMSF) is an international experiment facilitated by the NASA Glenn Research Center and under the guidance of U.S. principal investor Professor Hegseth of the University of New Orleans and three French coinvestigators: Daniel Beysens, Yves Garrabos, and Carole Chabot. The GMSF experiments were concluded in early 1999 on the Russian space station Mir. The experiments spanned the three science themes of near-critical phase separation rates, interface dynamics in near-critical boiling, and measurement of the spectrum of density fluctuation length scales very close to the critical point. The fluids used were pure CO2 or SF6. Three of the five thermostats used could adjust the sample volume with the scheduled crew time. Such a volume adjustment enabled variable sample densities around the critical density as well as pressure steps (as distinct from the usual temperature steps) applied to the sample. The French-built ALICE II facility was used for these experiments. It allows tightly thermostated (left photograph) samples (right photograph) to be controlled and viewed/measured. Its diagnostics include interferometry, shadowgraph, high-speed pressure measurements, and microscopy. Data were logged on DAT tapes, and PCMCIA cards and were returned to Earth only after the mission was over. The ground-breaking near critical boiling experiment has yielded the most results with a paper published in Physical Review Letters (ref. 1). The boiling work also received press in Science Magazine (ref. 2). This work showed that, in very compressible near-critical two-phase pure fluids, a vapor bubble was induced to temporarily overheat during a rapid heating of the sample wall. The temperature rise in the vapor was 23-percent higher than the rise in the driving container wall. The effect is due to adiabatic compression of the vapor bubble by the rapid expansion of fluid near the boundary during heatup. Thermal diffusivity is low near the

  10. Lunar electrical conductivity, permeability,and temperature from Apollo magnetometer experiments

    NASA Technical Reports Server (NTRS)

    Dyal, P.; Parkin, C. W.; Daily, W. D.

    1974-01-01

    Magnetometers were deployed at four Apollo sites on the moon to measure remanent and induced lunar magnetic fields. Measurements from this network of instruments were used to calculate the electrical conductivity, temperature, magnetic permeability, and iron abundance of the lunar interior. Global lunar fields due to eddy currents, induced in the lunar interior by magnetic transients, were analyzed to calculate and electrical conductivity profile for the moon, and those profiles were used to calculate the lunar temperature for an assumed lunar material of olivine. Simultaneous measurements by magnetometers on the lunar surface and in orbit around the moon were use to construct a whole-moon hysteresis curve, from which the global lunar magnetic permeability is determined. Total iron abundance (sum of iron in the ferromagnetic and paramagnetic states) was calculated for two assumed compositional models of the lunar interior. Other lunar models with an iron core and with a shallow iron-rich layer also discussed in light of the measured global lunar permeability. Simultaneous magnetic field and solar plasma pressure measurements show that the remanent fields at the Apollo 12 and 16 sites interact with, and are compressed by, the solar wind. Velocities and thicknesses of the earth's magnetopause and bow shock were also estimated from simultaneous magnetometer measurements.

  11. Pore Formation and Mobility Investigation (PFMI): Concept, Hardware Development, and Initial Analysis of Experiments Conducted Aboard the International Space Station

    NASA Technical Reports Server (NTRS)

    Grugel, Richard N.

    2003-01-01

    Porosity in the form of "bubbles and pipes" can occur during controlled directional solidification processing of metal alloys. This is a consequence that 1) precludes obtaining any meaningful scientific results and 2) is detrimental to desired material properties. Unfortunately, several Microgravity experiments have been compromised by porosity. The intent of the PFMl investigation is to conduct a systematic effort directed towards understanding porosity formation and mobility during controlled directional solidification (DS) in a microgravity environment. PFMl uses a pure transparent material, succinonitrile (SCN), as well as SCN "alloyed" with water, in conjunction with a translating temperature gradient stage so that direct observation and recording of pore generation and mobility can be made. PFMl is investigating the role of thermocapillary forces and temperature gradients in affecting bubble dynamics as well as other solidification processes in a microgravity environment. This presentation will cover the concept, hardware development, operations, and the initial results from experiments conducted aboard the International Space Station.

  12. Long-Term Network Experiments and Interdisciplinary Campaigns Conducted by the USDA-Agricultural Research Service

    NASA Astrophysics Data System (ADS)

    Goodrich, D. C.; Kustas, W. P.; Cosh, M. H.; Moran, S. M.; Marks, D. G.; Jackson, T. J.; Bosch, D. D.; Rango, A.; Seyfried, M. S.; Scott, R. L.; Prueger, J. H.; Starks, P. J.; Walbridge, M. R.

    2014-12-01

    The USDA-Agricultural Research Service has led, or been integrally involved in, a myriad of interdisciplinary field campaigns in a wide range of locations both nationally and internationally. Many of the shorter campaigns were anchored over the existing national network of ARS Experimental Watersheds and Rangelands. These long-term outdoor laboratories provided a critical knowledge base for designing the campaigns as well as historical data, hydrologic and meteorological infrastructure coupled with shop, laboratory, and visiting scientist facilities. This strong outdoor laboratory base enabled cost-efficient campaigns informed by historical context, local knowledge, and detailed existing watershed characterization. These long-term experimental facilities have also enabled much longer term lower intensity experiments, observing and building an understanding of both seasonal and inter-annual biosphere-hydrosphere-atmosphere interactions across a wide range of conditions. A sampling of these experiments include MONSOON'90, SGP97, SGP99, Washita'92, Washita'94, SMEX02-05 and JORNEX series of experiments, SALSA, CLASIC and longer-term efforts over the ARS Little Washita, Walnut Gulch, Little River, Reynolds Creek, and OPE3 Experimental Watersheds. This presentation will review some of the highlights and key findings of these campaigns and long-term efforts including the inclusion of many of the experimental watersheds and ranges in the Long-Term Agro-ecosystems Research (LTAR) network. The LTAR network also contains several locations that are also part of other observational networks including the CZO, LTER, and NEON networks. Lessons learned will also be provided for scientists initiating their participation in large-scale, multi-site interdisciplinary science.

  13. Localization and physical properties experiments conducted by Spirit at Gusev crater

    USGS Publications Warehouse

    Arvidson, R. E.; Anderson, R.C.; Bartlett, P.; Bell, J.F., III; Blaney, D.; Christensen, P.R.; Chu, P.; Crumpler, L.; Davis, K.; Ehlmann, B.L.; Fergason, R.; Golombek, M.P.; Gorevan, S.; Grant, J. A.; Greeley, R.; Guinness, E.A.; Haldemann, A.F.C.; Herkenhoff, K.; Johnson, J.; Landis, G.; Li, R.; Lindemann, R.; McSween, H.; Ming, D. W.; Myrick, T.; Richter, L.; Seelos, F.P., IV; Squyres, S. W.; Sullivan, R.J.; Wang, A.; Wilson, Jim

    2004-01-01

    The precise location and relative elevation of Spirit during its traverses from the Columbia Memorial station to Bonneville crater were determined with bundle-adjusted retrievals from rover wheel turns, suspension and tilt angles, and overlapping images. Physical properties experiments show a decrease of 0.2% per Mars solar day in solar cell output resulting from deposition of airborne dust, cohesive soil-like deposits in plains and hollows, bright and dark rock coatings, and relatively weak volcanic rocks of basaltic composition. Volcanic, impact, aeolian, and water-related processes produced the encountered landforms and materials.

  14. Localization and physical properties experiments conducted by Spirit at Gusev Crater

    NASA Technical Reports Server (NTRS)

    Arvidson, R. E.; Anderson, R. C.; Bartlett, P.; Bell, J. F., III; Blaney, D.; Christensen, P. R.; Chu, P.; Crumpler, L.; Davis, K.; Ehlmann, B. L.; Fergason, R.; Golombek, M. P.; Gorevan, S.; Grant, J. A.; Greeley, R.; Guinness, E. A.; Haldemann, A. F. C.; Herkenhoff, K.; Johnson, J.; Landis, G.; Li, R.; Lindemann, R.; Ming, D. W.

    2004-01-01

    The precise location and relative elevation of Spirit during its traverses from the Columbia Memorial station to Bonneville crater were determined with bundle-adjusted retrievals from rover wheel turns, suspension and tilt angles, and overlapping images. Physical properties experiments show a decrease of 0.2% per Mars solar day in solar cell output resulting from deposition of airborne dust, cohesive soil-like deposits in plains and hollows, bright and dark rock coatings, and relatively weak volcanic rocks of basaltic composition. Volcanic, impact, aeolian, and water-related processes produced the encountered landforms and materials.

  15. STS-47 MS Davis and MS Jemison conduct LBNP experiment in the SLJ module

    NASA Technical Reports Server (NTRS)

    1992-01-01

    At the aft end of the Spacelab Japan (SLJ) science module, STS-47 Mission Specialist (MS) N. Jan Davis (foreground) readies Rack 9 Automatic Blood Pressure System (ABPS) controls as MS Mae C. Jemison, inside the cylindrical fabric lower body negative pressure (LBNP) device, waits for the LBNP experiment to begin. LBNP device is sealed around Jemison's waist. It is attached to the SLJ floor and has a controller that operates a pump to change the pressure inside. Davis will monitor Jemison's pulse rate, blood pressure, and cardiac dimensions and functions.

  16. A summary of the test procedures and operational details of an ocean dumping pollution monitoring experiment conducted 7 October 1976

    NASA Technical Reports Server (NTRS)

    Hypes, W. D.; Wallace, J. W.; Gurganus, E. A.

    1977-01-01

    A remote sensor experiment was conducted at a sewage sludge dump site off the Delaware/Maryland coast. Two aircraft serving as remote sensor platforms flew over the dump site during a sludge dump. One aircraft carried a multispectral scanner and the other aircraft carried a rapid scanning spectrometer. Data from sea-truth stations were collected concurrent with overpasses of the aircraft. All sensors were operational and produced good digital data.

  17. Deformation of a nearly hemispherical conducting drop due to an electric field: Theory and experiment

    NASA Astrophysics Data System (ADS)

    Corson, L. T.; Tsakonas, C.; Duffy, B. R.; Mottram, N. J.; Sage, I. C.; Brown, C. V.; Wilson, S. K.

    2014-12-01

    We consider, both theoretically and experimentally, the deformation due to an electric field of a pinned nearly hemispherical static sessile drop of an ionic fluid with a high conductivity resting on the lower substrate of a parallel-plate capacitor. Using both numerical and asymptotic approaches, we find solutions to the coupled electrostatic and augmented Young-Laplace equations which agree very well with the experimental results. Our asymptotic solution for the drop interface extends previous work in two ways, namely, to drops that have zero-field contact angles that are not exactly π/2 and to higher order in the applied electric field, and provides useful predictive equations for the changes in the height, contact angle, and pressure as functions of the zero-field contact angle, drop radius, surface tension, and applied electric field. The asymptotic solution requires some numerical computations, and so a surprisingly accurate approximate analytical asymptotic solution is also obtained.

  18. Effects of biochar addition on greenhouse gas emissions and microbial responses in a short-term laboratory experiment.

    PubMed

    Yoo, Gayoung; Kang, Hojeong

    2012-01-01

    Biochar application to soil has drawn much attention as a strategy to sequester atmospheric carbon in soil ecosystems. The applicability of this strategy as a climate change mitigation option is limited by our understanding of the mechanisms responsible for the observed changes in greenhouse gas emissions from soils, microbial responses, and soil fertility changes. We conducted an 8-wk laboratory incubation using soils from PASTURE (silt loam) and RICE PADDY (silt loam) sites with and without two types of biochar (biochar from swine manure [CHAR-M] and from barley stover [CHAR-B]). Responses to addition of the different biochars varied with the soil source. Addition of CHAR-B did not change CO and CH evolution from the PASTURE or the RICE PADDY soils, but there was a decrease in NO emissions from the PASTURE soil. The effects of CHAR-M addition on greenhouse gas emissions were different for the soils. The most substantial change was an increase in NO emissions from the RICE PADDY soil. This result was attributed to a combination of abundant denitrifiers in this soil and increased net nitrogen mineralization. Soil phosphatase and N-acetylglucosaminidase activity in the CHAR-B-treated soils was enhanced compared with the controls for both soils. Fungal biomass was higher in the CHAR-B-treated RICE PADDY soil. From our results, we suggest CHAR-B to be an appropriate amendment for the PASTURE and RICE PADDY soils because it provides increased nitrogen availability and microbial activity with no net increase in greenhouse gas emissions. Application of CHAR-M to RICE PADDY soils could result in excess nitrogen availability, which may increase NO emissions and possible NO leaching problems. Thus, this study confirms that the ability of environmentally sound biochar additions to sequester carbon in soils depends on the characteristics of the receiving soil as well as the nature of the biochar. PMID:22751062

  19. Localization and physical property experiments conducted by opportunity at Meridiani Planum

    USGS Publications Warehouse

    Arvidson, R. E.; Anderson, R.C.; Bartlett, P.; Bell, J.F., III; Christensen, P.R.; Chu, P.; Davis, K.; Ehlmann, B.L.; Golombek, M.P.; Gorevan, S.; Guinness, E.A.; Haldemann, A.F.C.; Herkenhoff, K. E.; Landis, G.; Li, R.; Lindemann, R.; Ming, D. W.; Myrick, T.; Parker, T.; Richter, L.; Seelos, F.P., IV; Soderblom, L.A.; Squyres, S. W.; Sullivan, R.J.; Wilson, Jim

    2004-01-01

    The location of the Opportunity landing site was determined to better than 10-m absolute accuracy from analyses of radio tracking data. We determined Rover locations during traverses with an error as small as several centimeters using engineering telemetry and overlapping images. Topographic profiles generated from rover data show that the plains are very smooth from meter- to centimeter-length scales, consistent with analyses of orbital observations. Solar cell output decreased because of the deposition of airborne dust on the panels. The lack of dust-covered surfaces on Meridiani Planum indicates that high velocity winds must remove this material on a continuing basis. The low mechanical strength of the evaporitic rocks as determined from grinding experiments, and the abundance of coarse-grained surface particles argue for differential erosion of Meridiani Planum.

  20. Localization and physical property experiments conducted by Opportunity at Meridiani Planum.

    PubMed

    Arvidson, R E; Anderson, R C; Bartlett, P; Bell, J F; Christensen, P R; Chu, P; Davis, K; Ehlmann, B L; Golombek, M P; Gorevan, S; Guinness, E A; Haldemann, A F C; Herkenhoff, K E; Landis, G; Li, R; Lindemann, R; Ming, D W; Myrick, T; Parker, T; Richter, L; Seelos, F P; Soderblom, L A; Squyres, S W; Sullivan, R J; Wilson, J

    2004-12-01

    The location of the Opportunity landing site was determined to better than 10-m absolute accuracy from analyses of radio tracking data. We determined Rover locations during traverses with an error as small as several centimeters using engineering telemetry and overlapping images. Topographic profiles generated from rover data show that the plains are very smooth from meter- to centimeter-length scales, consistent with analyses of orbital observations. Solar cell output decreased because of the deposition of airborne dust on the panels. The lack of dust-covered surfaces on Meridiani Planum indicates that high velocity winds must remove this material on a continuing basis. The low mechanical strength of the evaporitic rocks as determined from grinding experiments, and the abundance of coarse-grained surface particles argue for differential erosion of Meridiani Planum. PMID:15576608

  1. Conducting Science with a CubeSat: The Colorado Student Space Weather Experiment (CSSWE)

    NASA Astrophysics Data System (ADS)

    Palo, Scott; Li, Xinlin; Gerhardt, David; Blum, Lauren; Schiller, Quintin; Kohnert, Rick

    2014-06-01

    The Colorado Student Space Weather Experiment is a 3-unit (10cm x 10cm x 30cm) CubeSat funded by the National Science Foundation and constructed at the University of Colorado (CU). The CSSWE science instrument, the Relativistic Electron and Proton Telescope integrated little experiment (REPTile), provides directional differential flux measurements of 0.5 to >3.3 MeV electrons and 9 to 40 MeV protons. Though a collaboration of 60+ multidisciplinary graduate and undergraduate students working with professors and professional engineers, CSSWE was designed, built, tested, and delivered in 3 years. On September 13, 2012, CSSWE was inserted to a 477 x 780 km, 65° orbit as a secondary payload on an Atlas V through the NASA Educational Launch of Nanosatellites (ELaNa) program.The first successful contact with CSSWE was made within a few hours of launch. CSSWE then completed a 20 day system commissioning phase which validated the performance of the communications, power, and attitude control systems. This was immediately followed by an accelerated 24 hour REPTile commissioning period in time for a geomagnetic storm. The high quality, low noise science data return from REPTile is complementary to the NASA Van Allen Probes mission, which launched two weeks prior to CSSWE. On January 5, 2013, CSSWE completed 90 days of on-orbit science operations, achieving the baseline goal for full mission success and has been operating since. An overview of the CSSWE system, on-orbit performance and lessons learned will be presented.

  2. Conductance tomography of conductive filaments in intrinsic silicon-rich silica RRAM† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr04982b Click here for additional data file.

    PubMed Central

    Montesi, Luca; Hudziak, Stephen; Mehonic, Adnan

    2015-01-01

    We present results from an imaging study of filamentary conduction in silicon suboxide resistive RAM devices. We used a conductive atomic force microscope to etch through devices while measuring current, allowing us to produce tomograms of conductive filaments. To our knowledge this is the first report of such measurements in an intrinsic resistance switching material. PMID:26482563

  3. Analysis of pin removal experiments conducted in an SCWR-like test lattice

    SciTech Connect

    Chawla, R.; Raetz, D.; Jordan, K. A.; Perret, G.

    2012-07-01

    A comprehensive program of integral experiments, largely based on the measurement of reaction rate distributions, was carried out recently on an SCWR-like fuel lattice in the central test zone of the PROTEUS zero-power research reactor at the Paul Scherrer Inst. in Switzerland. The present paper reports on the analysis of a complementary set of measurements, in which the reactivity effects of removing individual pins from the unperturbed, heterogeneously moderated reference lattice were investigated. It has been found that the detailed Monte Carlo modeling of the whole reactor using MCNPX is able - as in the case of the reaction rate distributions - to reproduce the experimental results for the pin removal worths within the achievable statistical accuracy. A comparison of reduced-geometry calculations between MCNPX and the deterministic LWR assembly code CASMO-4E has revealed certain discrepancies. On the basis of a reactivity decomposition analysis of the differences between the codes, it has been suggested that these could be due to CASMO-4E deficiencies in calculating the effect, upon pin removal, of the extra moderation in the neighboring fuel pins. (authors)

  4. Calibration Experiments Conducted for Noninvasive Blood Glucose Sensing Through the Eye

    NASA Technical Reports Server (NTRS)

    Ansari, Rafat R.; Bockle, Stefan; Suh, Kwang I.; Rovati, Luigi L.

    2004-01-01

    There are more than 16 million diabetics in the United States and more than 100 million worldwide. Diabetes can lead to severe complications over time such as blindness, renal and cardiovascular diseases, and peripheral neuropathy in the limbs. Poor blood circulation in diabetics can lead to gangrene and the subsequent amputation of extremities. In addition, this pathology is the fourth leading cause of death in the United States. The most effective way to manage diabetes is frequent blood glucose monitoring performed by the patients themselves. However, because of pain, inconvenience, and the fear of developing infections from finger-prick blood tests or implants, many patients monitor their blood glucose levels less frequently than is recommended by their physicians. Therefore, a noninvasive, painless, and convenient method to monitor blood glucose would greatly benefit diabetics. Likewise, detecting, preventing, and treating the untoward effects of prolonged space travel (e.g., a human mission to Mars) in real-time requires the development of noninvasive diagnostic technologies that are compact and powerful. As a "window to the body," the eye offers the opportunity to use light in various forms to detect ocular and systemic abnormalities long before clinical symptoms appear and to help develop preventative and therapeutic countermeasures early. The noninvasive feature of these technologies permits frequent repetition of tests, enabling an evaluation of the response to therapy.

  5. High-Pressure Multi-Mbar Conductivity Experiments on Hydrogen: The Quest for Solid Metallic Hydrogen

    SciTech Connect

    Jackson, D

    2007-02-07

    Ultra-dense hydrogen has long been the subject of intense experimental and theoretical research due to the fascinating physics which arises from this supposedly simple system. The properties of ultra-dense hydrogen also have important implications for planetary physics, since the interiors of the giant planets Jupiter and Saturn are believed to consist of cores of dense, metallic hydrogen. Finally, ultra-dense hydrogen is of direct programmatic interest, and multiple-shock compression experiments on hydrogen to the metallic state have stimulated the accelerated development of new hydrogen equation-of-state (EOS) models used for ICF and other applications. The focus of our research has often been described as the ''Holy Grail'' of high-pressure physics research: The metallization of solid hydrogen. Metallic hydrogen has long been considered to be the prototypical system for the study of insulator-to-metal (I-M) transitions. Although metallic hydrogen (Z=1) may superficially appear to be a very simple material, it is in fact an extremely challenging system for theoretical analysis due to the presence of large zero-point atomic motions and the complete absence of any core electrons. Thus, solid metallic hydrogen promises to be a fascinating material. Among its predicted properties is the possibility of being a high temperature superconductor with a critical temperature T{sub c} of the order of {approx} 100K [1]. The successful metallization of solid hydrogen would be a groundbreaking scientific discovery and open up new frontiers in science and possibly technology as well.

  6. Association of interatrial septal abnormalities with cardiac impulse conduction disorders in adult patients: experience from a tertiary center in Kosovo

    PubMed Central

    Bakalli, Aurora; Pllana, Ejup; Koçinaj, Dardan; Bekteshi, Tefik; Dragusha, Gani; Gashi, Masar; Musliu, Nebih; Gashi, Zaim

    2011-01-01

    Interatrial septal disorders, which include: atrial septal defect, patent foramen ovale and atrial septal aneurysm, are frequent congenital anomalies found in adult patients. Early detection of these anomalies is important to prevent their hemodynamic and/or thromboembolic consequences. The aims of this study were: to assess the association between impulse conduction disorders and anomalies of interatrial septum; to determine the prevalence of different types of interatrial septum abnormalities; to assess anatomic, hemodynamic, and clinical consequences of interatrial septal pathologies. Fifty-three adult patients with impulse conduction disorders and patients without ECG changes but with signs of interatrial septal abnormalities, who were referred to our center for echocardiography, were included in a prospective transesophageal echocardiography study. Interatrial septal anomalies were detected in around 85% of the examined patients. Patent foramen ovale was encountered in 32% of the patients, and in combination with atrial septal aneurysm in an additional 11.3% of cases. Atrial septal aneurysm and atrial septal defect were diagnosed with equal frequency in 20.7% of our study population. Impulse conduction disorders were significantly more suggestive of interatrial septal anomalies than clinical signs and symptoms observed in our patients (84.91% vs 30.19%, P=0.002). Right bundle branch block was the most frequent impulse conduction disorder, found in 41 (77.36%) cases. We conclude that interatrial septal anomalies are highly associated with impulse conduction disorders, particularly with right bundle branch block. Impulse conduction disorders are more indicative of interatrial septal abnormalities in earlier stages than can be understood from the patient’s clinical condition. PMID:21977304

  7. Association of interatrial septal abnormalities with cardiac impulse conduction disorders in adult patients: experience from a tertiary center in Kosovo.

    PubMed

    Bakalli, Aurora; Pllana, Ejup; Koçinaj, Dardan; Bekteshi, Tefik; Dragusha, Gani; Gashi, Masar; Musliu, Nebih; Gashi, Zaim

    2011-01-01

    INTERATRIAL SEPTAL DISORDERS, WHICH INCLUDE: atrial septal defect, patent foramen ovale and atrial septal aneurysm, are frequent congenital anomalies found in adult patients. Early detection of these anomalies is important to prevent their hemodynamic and/or thromboembolic consequences. The aims of this study were: to assess the association between impulse conduction disorders and anomalies of interatrial septum; to determine the prevalence of different types of interatrial septum abnormalities; to assess anatomic, hemodynamic, and clinical consequences of interatrial septal pathologies. Fifty-three adult patients with impulse conduction disorders and patients without ECG changes but with signs of interatrial septal abnormalities, who were referred to our center for echocardiography, were included in a prospective transesophageal echocardiography study. Interatrial septal anomalies were detected in around 85% of the examined patients. Patent foramen ovale was encountered in 32% of the patients, and in combination with atrial septal aneurysm in an additional 11.3% of cases. Atrial septal aneurysm and atrial septal defect were diagnosed with equal frequency in 20.7% of our study population. Impulse conduction disorders were significantly more suggestive of interatrial septal anomalies than clinical signs and symptoms observed in our patients (84.91% vs 30.19%, P=0.002). Right bundle branch block was the most frequent impulse conduction disorder, found in 41 (77.36%) cases. We conclude that interatrial septal anomalies are highly associated with impulse conduction disorders, particularly with right bundle branch block. Impulse conduction disorders are more indicative of interatrial septal abnormalities in earlier stages than can be understood from the patient's clinical condition. PMID:21977304

  8. Ion Pair Asociation in Ultra Supercritical Aqueous Environments: Successful Interplay between Conductance Experiment, Theory and Molecular Simulation.

    SciTech Connect

    Chialvo, Ariel A; Gruszkiewicz, Miroslaw {Mirek} S; Cole, David R

    2010-01-01

    We discuss the interplay between theory, molecular simulation and electric conductance experiments as an important tool for the extraction of ion-pair interaction potentials to make possible the bridging of the density gap between the lowest experimentally attainable conductance measurement and the theoretically reachable zero-density limit of the ion-pair association constant. Then, we predict the density dependence of the Na+!Cl! pair association constant in ultra supercritical steam environments by constraint molecular dynamics simulation over state conditions relevant to the new generation of ultra-supercritical steam power plants. Finally, we draw attention to relevant modeling challenges associated to the behavior of these systems around the zero-density limit and discuss ways to overcome them.

  9. 30 CFR 250.406 - What additional safety measures must I take when I conduct drilling operations on a platform that...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... when I conduct drilling operations on a platform that has producing wells or has other hydrocarbon flow... when I conduct drilling operations on a platform that has producing wells or has other hydrocarbon flow... producing wells or that has other hydrocarbon flow: (a) You must install an emergency shutdown station...

  10. 30 CFR 250.406 - What additional safety measures must I take when I conduct drilling operations on a platform that...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... when I conduct drilling operations on a platform that has producing wells or has other hydrocarbon flow... when I conduct drilling operations on a platform that has producing wells or has other hydrocarbon flow... producing wells or that has other hydrocarbon flow: (a) You must install an emergency shutdown station...

  11. 30 CFR 250.406 - What additional safety measures must I take when I conduct drilling operations on a platform that...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... when I conduct drilling operations on a platform that has producing wells or has other hydrocarbon flow... hydrocarbon flow? You must take the following safety measures when you conduct drilling operations on a platform with producing wells or that has other hydrocarbon flow: (a) You must install an...

  12. 30 CFR 250.406 - What additional safety measures must I take when I conduct drilling operations on a platform that...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... when I conduct drilling operations on a platform that has producing wells or has other hydrocarbon flow... when I conduct drilling operations on a platform that has producing wells or has other hydrocarbon flow... producing wells or that has other hydrocarbon flow: (a) You must install an emergency shutdown station...

  13. 5 CFR 1001.101 - In addition to this part, what other rules of conduct apply to Office of Personnel Management...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Management at 5 CFR part 4501; (g) The Employee Responsibilities and Conduct regulations at 5 CFR part 735... rules of conduct apply to Office of Personnel Management employees? 1001.101 Section 1001.101 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) REGULATIONS GOVERNING EMPLOYEES OF THE...

  14. 5 CFR 1001.101 - In addition to this part, what other rules of conduct apply to Office of Personnel Management...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Management at 5 CFR part 4501; (g) The Employee Responsibilities and Conduct regulations at 5 CFR part 735... rules of conduct apply to Office of Personnel Management employees? 1001.101 Section 1001.101 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) REGULATIONS GOVERNING EMPLOYEES OF THE...

  15. 5 CFR 1001.101 - In addition to this part, what other rules of conduct apply to Office of Personnel Management...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Management at 5 CFR part 4501; (g) The Employee Responsibilities and Conduct regulations at 5 CFR part 735... rules of conduct apply to Office of Personnel Management employees? 1001.101 Section 1001.101 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) REGULATIONS GOVERNING EMPLOYEES OF THE...

  16. Soil apparent conductivity measurements for planning and analysis of agricultural experiments: A case study from Western-Thailand

    NASA Astrophysics Data System (ADS)

    Rudolph, Sebastian; Wongleecharoen, Chalermchart; Lark, Richard Murray; Marchant, Ben Paul; Garré, Sarah; Herbst, Michael; Vereecken, Harry; Weihermueller, Lutz

    2016-04-01

    In agricultural experiments the success or failure of a potential improvement is generally evaluated based on the plant response, using proper experimental designs with sufficient statistical power. Because within-site variability can negatively affect statistical power, improvements in the experimental design can be achieved if this variation is well understood and incorporated into the experimental design, or if some surrogate variable is used as a covariate in the analysis. Apparent soil electrical conductivity (ECa), measured by electromagnetic induction (EMI) may be one source of this information. The objective of this study was to investigate the effectiveness of EMI-derived ECa measurements for planning and analysis of agricultural experiments. ECa and plant height measurements of maize (the response variable) were taken from an agricultural experiment in Western Thailand. A statistical model of these variables was used to simulate experiments with different designs and treatment effects. The simulated data were used to quantify the statistical power when testing three orthogonal contrasts. The following experimental designs were considered: a simple random design (SR), a complete randomized block design (CRB), and a complete randomized block design with spatially adjusted blocks on plot means of ECa (CRBECa). According to an analysis of variance (ANOVA) the smallest effect sizes could be detected using the CRBECa design, which suggests that ECa survey measurements could be used in the planning phase of an experiment to achieve efficiencies by better blocking. Also, analysis of covariance (ANCOVA) showed that larger power improvements could be achieved when ECa was used as a covariate in the analysis. We therefore recommend that ECa measurements should be used to describe subsurface variability and to support the statistical analysis of agricultural experiments.

  17. External validity of Concealed Information Test experiment: Comparison of respiration, skin conductance, and heart rate between experimental and field card tests.

    PubMed

    Zaitsu, Wataru

    2016-07-01

    The Concealed Information Test (CIT) is a memory detection method based on an examinee's physiological responses to crime-relevant items (critical items) in comparison with crime-irrelevant items (noncritical items). I examined the external validity of CIT laboratory experiments by comparing respiratory speed (RS), skin conductance response (SCR), and heart rate (HR) between a laboratory experiment (n = 30) and a field test (n = 30) in a card test. A linear mixed models analysis showed that the critical items in both CIT contexts elicited CIT effects: RS repression, SCR increase, and HR deceleration. Additionally, the critical items in the field elicited a larger RS suppression than those in the laboratory; however, SCR and HR on the critical items showed no statistical differences between the laboratory and field CITs. Moreover, the tonic HRs in the field tests were higher than in the CIT experiments, but there were no significant correlations between the tonic HR and each CIT effect in RS, SCR, and HR. These results suggested that CIT detection efficiency was not affected by arousal levels and may imply that the CIT effects observed with RS, SCR, and HR in the CIT laboratory experiments has adequate external validity and can be generalized to the CIT field. PMID:27031043

  18. Determination of Unknown Concentrations of Sodium Acetate Using the Method of Standard Addition and Proton NMR: An Experiment for the Undergraduate Analytical Chemistry Laboratory

    ERIC Educational Resources Information Center

    Rajabzadeh, Massy

    2012-01-01

    In this experiment, students learn how to find the unknown concentration of sodium acetate using both the graphical treatment of standard addition and the standard addition equation. In the graphical treatment of standard addition, the peak area of the methyl peak in each of the sodium acetate standard solutions is found by integration using…

  19. Perspectives, perceptions and experiences in postoperative pain management in developing countries: A focus group study conducted in Rwanda

    PubMed Central

    Johnson, Ana P; Mahaffey, Ryan; Egan, Rylan; Twagirumugabe, Theogene; Parlow, Joel L

    2015-01-01

    BACKGROUND: Access to postoperative acute pain treatment is an important component of perioperative care and is frequently managed by a multidisciplinary team of anesthesiologists, surgeons, pharmacists, technicians and nurses. In some developing countries, treatment modalities are often not performed due to scarce health care resources, knowledge deficiencies and cultural attitudes. OBJECTIVES: In advance of a comprehensive knowledge translation initiative, the present study aimed to determine the perspectives, perceptions and experiences of anesthesia residents regarding postoperative pain management strategies. METHODS: The present study was conducted using a qualitative assessment strategy in a large teaching hospital in Rwanda. During two sessions separated by seven days, a 10-participant semistructured focus group needs analysis was conducted with anesthesia residents at the Centre Hospitalier Universitaire de Kigali (Kigali, Rwanda). Field notes were analyzed using interpretative and descriptive phenomenological approaches. Participants were questioned regarding their perspectives, perceptions and experiences in pain management. RESULTS: The responses from the focus groups were related to five general areas: general patient and medical practice management; knowledge base regarding postoperative pain management; pain evaluation; institutional/system issues related to protocol implementation; and perceptions about resource allocation. Within these areas, challenges (eg, communication among stakeholders and with patients) and opportunities (eg, on-the-job training, use of protocols, routine pain assessment, participation in resource allocation decisions) were identified. CONCLUSIONS: The present study revealed the prevalent challenges residents perceive in implementing postoperative pain management strategies, and offers practical suggestions to overcoming them, primarily through training and the implementation of practice recommendations. PMID:26448971

  20. The role of space communication in promoting national development with specific reference to experiments conducted in India

    NASA Astrophysics Data System (ADS)

    Chitnis, E. V.

    The paper describes the role of space communication in promoting national development with special reference to experiments conducted in India, namely SITE (1975-1976), STEP (1977-1979) and APPLE (1981 onwards). The impact of these experiments in economic, cultural and educational terms are discussed, pointing out social implications involved in using advance space communication technology for instruction and information in the areas of education, national integration and development. The paper covers special requirements which arise when a communication system covers backward and remote rural areas in a developing country. The impact on the population measured by conducting social surveys has been discussed - especially the gains of predominently illiterate new media - participants have been highlighted. Possibilities of improving skills of teachers, the quality of the primary and higher education have been covered. The preparation required both on ground as well as space to derive benefits of space technology are considered. A profile of INSAT which marks the culmination of the experimental phase and the beginning of operational domestic satellite system is sketched.

  1. Effect of phosphorus additions on the sintering and transport properties of proton conducting BaZr{sub 0.85}Y{sub 0.15}O{sub 3-{delta}}

    SciTech Connect

    Soares, H.S.; Zhang, X.; Antunes, I.; Frade, J.R.; Mather, G.C.; Fagg, D.P.

    2012-07-15

    The influence of phosphorous additions on the sintering and electrical transport properties of the proton-conducting perovskite BaZr{sub 0.85}Y{sub 0.15}O{sub 3-{delta}} (BZY) has been studied with a view to the use of phosphates as typical dispersants for the formation of stabilised solid suspensions or as possible sintering aids. P{sub 2}O{sub 5} additions, (1-x)BZY{center_dot}xP{sub 2}O{sub 5}, monotonously promote densification in the intermediate compositional range 0.04{<=}x{<=}0.08. Nonetheless, BZY reacts with phosphorous forming the phase Ba{sub 3}(PO{sub 4}){sub 2} at temperatures as low as 600 Degree-Sign C. The associated loss of Ba from the perovskite, leads to a decrease in the perovskite lattice parameter, the formation of yttria-based impurity phases and impaired grain growth. Such reaction has an extremely detrimental effect on bulk and grain boundary conductivities. It is, therefore, vital that the current results are taken into account by the protonics community when attempting to prepare the stabilised solid suspensions of BZY nanopowders required for thin ceramic applications. Alternative dispersants to phosphate esters must be found. - Graphical Abstract: Sintering experiments performed at 1500 Degree-Sign C for 5 h and at 1400 Degree-Sign C for 24 h of (1-x)BaZr{sub 0.85}Y{sub 0.15}O{sub 3-{delta}}{center_dot}xP{sub 2}O{sub 5} in the range x=0-0.10. Highlights: Black-Right-Pointing-Pointer P{sub 2}O{sub 5} additions, (1-x)BZY{center_dot}xP{sub 2}O{sub 5}, promote densification in the intermediate compositional range 0.04{<=}x{<=}0.08. Black-Right-Pointing-Pointer BZY reacts with phosphorous forming the phase Ba{sub 3}(PO{sub 4}){sub 2} at temperatures as low as 600 Degree-Sign C. Black-Right-Pointing-Pointer Detrimental effects on bulk and grain boundary conductivities are shown. Black-Right-Pointing-Pointer Alternative dispersants to phosphate esters must be found.

  2. Trials and tribulations of conducting interventional studies in urban slums of a developing country: Experiences from Kolkata, India.

    PubMed

    Mahapatra, Tanmay; Mahapatra, Sanchita; Pal, Debottam; Saha, Jayanta; Lopez, AnnaLena; Ali, Mohammad; Bannerjee, Barnali; Manna, Byomkesh; Sur, Dipika; Bhattacharya, Sujit; Kanungo, Suman

    2016-01-01

    Experimental studies involving human subjects provide most internally valid evidences in epidemiological research due to their robust methodology. While conducting population-based interventional studies, to achieve external validity, inclusion of information from vulnerable groups like urban slum-dwellers of the developing world, in the epidemiological estimates is of paramount importance. The challenges faced while conducting 2 consecutive large-scale, community-based vaccine trials in urban slums of Kolkata, India are presented in this article. Interventions in these communities often get constrained by issues pertaining to human rights and benefits, socio-cultural factors, political environment, methodological shortcomings in addition to the challenges in ensuring community participation. While conducting these trials although we intermittently faced obstacles, by virtue of having a long term and robust surveillance system and developing a trusted relationship between the researchers, community leaders and residents we were able to come up with a commendable community participation which culminated into the success of the interventions. Bridging the gap between research and field operations by incorporating knowledge gathered from interventional studies and making strategies to improve health conditions of these informal settlers is a major unfulfilled agenda. We believe the lessons learnt during our research will help researchers while developing efficient interventions in similar setting. PMID:26224251

  3. Co-addition of manure increases the dissipation rates of tylosin A and the numbers of resistance genes in laboratory incubation experiments.

    PubMed

    Li, Qian; Wang, Yan; Zou, Yong-De; Liao, Xin-Di; Liang, Juan-Boo; Xin, Wen; Wu, Yin-Bao

    2015-09-15

    The behavior of veterinary antibiotics in the soil is commonly studied using the following methods to add antibiotics to the soil: (A) adding manure collected from animals fed a diet that includes antibiotics; (B) adding antibiotic-free animal manure spiked with antibiotics; and (C) the direct addition of antibiotics. However, most studies have only used methods (B) and (C) in their research, and few studies have simultaneously compared the different antibiotic addition methods. This study used tylosin A (TYLA) as a model antibiotic to compare the effects of these three commonly used antibiotic addition methods on the dissipation rates of TYLA and the numbers of resistance genes in laboratory incubation experiments. The results showed that the three treatment methods produced similar TYLA degradation trends; however, there were significant differences (P<0.05) in the TYLA degradation half-life (t1/2) among the three methods. The half-life of TYLA degradation in treatments A, B and C was 2.44 ± 0.04, 1.21 ± 0.03 and 5.13 ± 0.11 days, respectively. The presence of manure resulted in a higher electrical conductivity (EC), higher relative abundance of Citrobacter amalonaticus, higher macrolide resistant gene (ermB, ermF and ermT) count and lower ecological toxicity in the soil, which could partially explain the higher TYLA degradation rate in the treatments containing manure. The higher degradation rate of TYLA in treatment B when compared to treatment A could be due to the lower concentrations of tylosin B (TYLB) and tylosin D (TYLD). The main route for veterinary antibiotics to enter the soil is via the manure of animals that have been administered antibiotics. Therefore, the more appropriate method to study the degradation and ecotoxicity of antibiotic residues in the soil is by using manure from animals fed/administered the particular antibiotic rather than by adding the antibiotic directly to the soil. PMID:25958362

  4. 30 CFR 250.406 - What additional safety measures must I take when I conduct drilling operations on a platform that...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... when I conduct drilling operations on a platform that has producing wells or has other hydrocarbon flow... operations on a platform that has producing wells or has other hydrocarbon flow? You must take the following... hydrocarbon flow: (a) You must install an emergency shutdown station near the driller's console; (b) You...

  5. Understanding the POW experience: stress research and the implementation of the 1955 U.S. Armed Forces Code of Conduct.

    PubMed

    Genter, Robert

    2015-01-01

    Facing accusations about weak military discipline following the supposedly poor behavior of American soldiers held captive during the Korean War, President Dwight Eisenhower instituted a Code of Conduct for the Armed Services in 1955. In response, military leaders hired numerous social and behavioral scientists to investigate the nature of the prisoner-of-war (POW) experience. These researchers not only challenged official government accounts of POW activities but opened up a new field of study-stress research. They also changed military training policy, which soon focused more on stress inoculation training, and, in so doing, helped lead the shift in psychology away from behaviorism to ego and cognitive psychology. In this sense, my article ties shifts within the social and behavioral sciences in the 1950s to the military history of the early Cold War, a connection generally missing from most accounts of this period. PMID:25331009

  6. Containerless processing of glass forming melts: D-1, MEA/A-2 experiment 81F01 conducted on STS-61A flight, October 1985

    NASA Technical Reports Server (NTRS)

    Day, D. E.; Ray, C. S.

    1986-01-01

    Results of experiment 81F01, which was conducted in the Material Experiment Assembly MEA/A-2 on the D-1 Spacelab Mission (STS-61A), are presented. The general plan of the experiment was to heat, melt, and quench six spherical samples of different glass forming compositions while they were levitated in a single axis acoustic levitator furnace (SAAL). In addition, two non-melting sintered alumina samples were used to check the operational characteristics of the SAAL under reduced gravity conditions. Three of the eight samples were levitated between 1250 and 1500 C before the lack of coolant created an over-temperature condition that caused the SAAL to shut down prematurely. Two of the three samples processed were calcia-gallia-silica and soda-lime-silica glass forming compositions. Evidence of a two to three times increase in the tendency for glass formation was obtained for the calcia-gallia-silica. The final glass appeared reasonably homogeneous even though it was made from hot pressed powders containing deliberate heterogeneities. A photographic record was obtained of the microgravity sample processing sequences.

  7. Dynamic Characteristics of X-pinch Experiments Conducted in a Small Capacitive Generator:Refractive Optical Observations.

    NASA Astrophysics Data System (ADS)

    Sepúlveda, Adolfo; Pavez, Cristian; Pedreros, José; Avaria, Gonzalo; San Martín, Patricio; Soto, Leopoldo

    2016-05-01

    Among the dense plasmas configurations of interest for applications as a portable intense source of X-rays, the X-pinches are the most attractive by their brightness, source size, short duration and space localization, being particularly reproducible when they are conducted with fast pulsed power generators. In recent time, several characteristics of the dynamics and emission have been reproduced in compact generators (typically capacitive generators) of low current rise-rate (less than 0.5 kA/ns). In this work, a preliminary characterization of the dynamic of X-pinch plasma conducted in a small capacitive generator is reported. In order to obtain the plasma dynamics and quantitative information of the plasma density, the dark field Schlieren technique and interferometry were implemented. The experiments were carried out on the multipurpose generator (1.2 μF, 345 J, 47.5 nH, T/4=375 ns and Z = 0.2 Ω in short circuit) capable to produce currents up to 122 kA with 500 ns quarter period, when a charging voltage of 24 kV and metallic X-pinches are used as load. The electrical behavior of the discharge and the X-ray emission are monitored with a Rogowski coil and filtered PIN diodes respectively. For the refractive optical diagnostics a 532 nm frequency- doubled Nd-YAG laser was used. As from a single Schlieren record per shot, a sequence with the time evolution of the plasma is constructed. From the images, a similar dynamic of X- pinches conducted in fast generators of high current is observed, where structures such as coronal plasma, plasma flares and plasma jets are identified. The plasma dynamics observed from a VUV gated pinhole image system is compared with registered dynamic with refractive optical techniques.

  8. 2D divertor heat flux distribution using a 3D heat conduction solver in National Spherical Torus Experiment.

    PubMed

    Gan, K F; Ahn, J-W; Park, J-W; Maingi, R; McLean, A G; Gray, T K; Gong, X; Zhang, X D

    2013-02-01

    The divertor heat flux footprint in tokamaks is often observed to be non-axisymmetric due to intrinsic error fields, applied 3D magnetic fields or during transients such as edge localized modes. Typically, only 1D radial heat flux profiles are analyzed; however, analysis of the full 2D divertor measurements provides opportunities to study the asymmetric nature of the deposited heat flux. To accomplish this an improved 3D Fourier analysis method has been successfully applied in a heat conduction solver (TACO) to determine the 2D heat flux distribution at the lower divertor surface in the National Spherical Torus Experiment (NSTX) tokamak. This advance enables study of helical heat deposition onto the divertor. In order to account for heat transmission through poorly adhered surface layers on the divertor plate, a heat transmission coefficient, defined as the surface layer thermal conductivity divided by the thickness of the layer, was introduced to the solution of heat conduction equation. This coefficient is denoted as α and a range of values were tested in the model to ensure a reliable heat flux calculation until a specific value of α led to the constant total deposited energy in the numerical solution after the end of discharge. A comparison between 1D heat flux profiles from TACO and from a 2D heat flux calculation code, THEODOR, shows good agreement. Advantages of 2D heat flux distribution over the conventional 1D heat flux profile are also discussed, and examples of 2D data analysis in the study of striated heat deposition pattern as well as the toroidal degree of asymmetry of peak heat flux and heat flux width are demonstrated. PMID:23464209

  9. 2D divertor heat flux distribution using a 3D heat conduction solver in National Spherical Torus Experiment

    NASA Astrophysics Data System (ADS)

    Gan, K. F.; Ahn, J.-W.; Park, J.-W.; Maingi, R.; McLean, A. G.; Gray, T. K.; Gong, X.; Zhang, X. D.

    2013-02-01

    The divertor heat flux footprint in tokamaks is often observed to be non-axisymmetric due to intrinsic error fields, applied 3D magnetic fields or during transients such as edge localized modes. Typically, only 1D radial heat flux profiles are analyzed; however, analysis of the full 2D divertor measurements provides opportunities to study the asymmetric nature of the deposited heat flux. To accomplish this an improved 3D Fourier analysis method has been successfully applied in a heat conduction solver (TACO) to determine the 2D heat flux distribution at the lower divertor surface in the National Spherical Torus Experiment (NSTX) tokamak. This advance enables study of helical heat deposition onto the divertor. In order to account for heat transmission through poorly adhered surface layers on the divertor plate, a heat transmission coefficient, defined as the surface layer thermal conductivity divided by the thickness of the layer, was introduced to the solution of heat conduction equation. This coefficient is denoted as α and a range of values were tested in the model to ensure a reliable heat flux calculation until a specific value of α led to the constant total deposited energy in the numerical solution after the end of discharge. A comparison between 1D heat flux profiles from TACO and from a 2D heat flux calculation code, THEODOR, shows good agreement. Advantages of 2D heat flux distribution over the conventional 1D heat flux profile are also discussed, and examples of 2D data analysis in the study of striated heat deposition pattern as well as the toroidal degree of asymmetry of peak heat flux and heat flux width are demonstrated.

  10. SIMEx : a shallow integrated, multi-method hydrogeophysical monitoring experiment for CO2 storage conducted at Maguelone (Languedoc coastline, France).

    NASA Astrophysics Data System (ADS)

    Pezard, P. A.; Denchik, N.; Lofi, J.; Perroud, H.; Neyens, D.

    2012-04-01

    operations near 15 m depth confirms the presence of a small reservoir at this depth. Prior to gas injection, a whole set of pre-injection experiments have been conducted in order to prepare, test, and calibrate the Maguelone site for later experiments. The initial physical properties of the reservoir layer have been successfully characterized using downhole geophysical measurements (gamma ray, electrical and acoustical logging), followed by surface (electrical and seismic tomography) and surface-to-borehole (seismic) surveys. More recently, nitrogen injection was undertaken to measure the site response to gas injection. Nitrogen was chosen because of the reducing nature of the in-situ environment present in the shallow subsurface at Maguelone, precluding oxygen injection to avoid massive bacterial developments. The next phase of SIMEx will be that of CO2 injection using similar surface and downhole hydrogeophysical monitoring.

  11. A summary of the test procedures and operational details of a Delaware River and an ocean dumping pollution monitoring experiment conducted 28 August 1975

    NASA Technical Reports Server (NTRS)

    Hypes, W. D.; Ohlhorst, C. W.

    1977-01-01

    Two remote sensor evaluation experiments are discussed. One experiment was conducted at the DuPont acid-dump site off the Delaware coast. The second was conducted at an organic waste outfall in the Delaware River. The operational objective of obtaining simultaneous sea truth sampling with remote sensors overpasses was met. Descriptions of the test sites, sensors, sensor platforms, flight lines, sea truth data collected, and operational chronology are presented.

  12. Adaptation of the pore diffusion model to describe multi-addition batch uptake high-throughput screening experiments.

    PubMed

    Traylor, Steven J; Xu, Xuankuo; Li, Yi; Jin, Mi; Li, Zheng Jian

    2014-11-14

    Equilibrium isotherm and kinetic mass transfer measurements are critical to mechanistic modeling of binding and elution behavior within a chromatographic column. However, traditional methods of measuring these parameters are impractically time- and labor-intensive. While advances in high-throughput robotic liquid handling systems have created time and labor-saving methods of performing kinetic and equilibrium measurements of proteins on chromatographic resins in a 96-well plate format, these techniques continue to be limited by physical constraints on protein addition, incubation and separation times; the available concentration of protein stocks and process pools; and practical constraints on resin and fluid volumes in the 96-well format. In this study, a novel technique for measuring protein uptake kinetics (multi-addition batch uptake) has been developed to address some of these limitations during high-throughput batch uptake kinetic measurements. This technique uses sequential additions of protein stock to chromatographic resin in a 96-well plate and the subsequent removal of each addition by centrifugation or vacuum separation. The pore diffusion model was adapted here to model multi-addition batch uptake and was tested and compared with traditional batch uptake measurements of uptake of an Fc-fusion protein on an anion exchange resin. Acceptable agreement between the two techniques is achieved for the two solution conditions investigated here. In addition, a sensitivity analysis of the model to the physical inputs is presented and the advantages and limitations of the multi-addition batch uptake technique are explored. PMID:25311484

  13. Spectroscopic Laboratory Astrophysics Experiments Conducted at the LLNL EBIT Facility in Support of NASA's X-ray Astronomy Flight Program

    NASA Astrophysics Data System (ADS)

    Brown, Gregory V.; Adams, J. S.; Beiersdorfer, P.; Chen, H.; Clementson, J.; Frankel, M.; Graf, A.; Gu, M. F.; Kahn, S. M.; Kelley, R.; Kilbourne, C. A.; Koutroumpa, D.; Leutenegger, M.; Porter, F.; Wargelin, B.

    2009-12-01

    The electron beam ion trap (EBIT) facility located at the Lawrence Livermore National Laboratory has been used for laboratory astrophysics experiments for over 15 years. During this time, several unique spectrometers and operating modes have been developed and implemented, including high resolution grating and crystal spectrometers, a high-resolution, high-efficiency NASA/GSFC microcalorimeter array, and the ability to operate and record datawith the electron beam turned off, i.e., in the so-called magnetic trapping mode. Targeted experiments conducted at this facility have addressed specific problems faced by the X-ray astrophysics community and have provided accurate, complete sets of atomic data such as relative and absolute excitation cross sections, transition wavelengths, line polarization, and X-ray signatures of charge exchange recombination. Here we will present a brief overview of our facility and some of the more recent results including 1/4 keV band X- ray emission produced by charge exchange between L-shell sulfur ions and neutral gas, wavelengths and relative intensities of satellite X- ray lines from Na-like Fe XVI and their contribution to the Fe XVII line emission, and the relative intensities of the 3s-2p/3d-2p lines in F-like Fe XVIII and Ni XX. Part of this work was performed under the auspices of the U. S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 and is also supported by NASA grants to LLNL, GSFC, and Stanford University.

  14. Reflections on Doctoral Supervision: Drawing from the Experiences of Students with Additional Learning Needs in Two Universities

    ERIC Educational Resources Information Center

    Collins, Bethan

    2015-01-01

    Supervision is an essential part of doctoral study, consisting of relationship and process aspects, underpinned by a range of values. To date there has been limited research specifically about disabled doctoral students' experiences of supervision. This paper draws on qualitative, narrative interviews about doctoral supervision with disabled…

  15. Feasibility and Satisfaction with a Tailored Web-based Audit Intervention for Recalibrating Radiologists’ Thresholds for Conducting Additional Work-up

    PubMed Central

    Carney, Patricia A.; Geller, Berta M.; Sickles, Edward A.; Miglioretti, Diana L.; Aiello Bowles, Erin J.; Abraham, Linn; Feig, Stephen A.; Brown, David; Cook, Andrea J.; Yankaskas, Bonnie C.; Elmore, Joann G.

    2010-01-01

    Purpose To examine the feasibility of and satisfaction with a tailored web-based intervention designed to decrease radiologists' recommendation of inappropriate additional work-up following a screening mammogram. Methods We developed a web-based educational intervention designed to reduce inappropriate recall. Radiologists were randomly assigned to participate in an early intervention group or a late (control) intervention group, the latter of which served as a control for a nine-month follow-up period, after which they were invited to participate in the intervention. Intervention content was derived from our prior research and included three modules: 1) an introduction to audit statistics for mammography performance; 2) a review of data showing radiologists' inflated perceptions of medical malpractice risks related to breast imaging, and 3) a review of data on breast cancer risk among women seen in their practices. Embedded within the intervention were individualized audit data for each participating radiologists obtained from the national Breast Cancer Surveillance Consortium. Results Seventy-four radiologists (37.8%; 74/196) consented to the intervention, which was completed by 67.5% (27/40) of those randomized to the early intervention group and 41.2% (14/34) of those randomized to the late (control) group. Thus, a total of 41 (55%) completed the intervention. On average, three log-ins were used to complete the program (range 1–14), which took approximately 1 hour. Ninety-five percent found the program moderately to very helpful in understanding how to calculate basic performance measures. Ninety-three percent found viewing their own performance measures moderately to very helpful, and 83% reported it being moderately to very important to learn that the breast cancer risk in their screening population program was lower than perceived. The percentage of radiologists who reported that the risk of medical malpractice influences their recall rates dropped from 36

  16. Analysis of magnetic probe signals including effect of cylindrical conducting wall for field-reversed configuration experiment

    SciTech Connect

    Ikeyama, Taeko; Hiroi, Masanori; Nemoto, Yuuichi; Nogi, Yasuyuki

    2008-06-15

    A confinement field is disturbed by magnetohydrodynamic (MHD) motions of a field-reversed configuration (FRC) plasma in a cylindrical conductor. The effect of the conductor should be included to obtain a spatial structure of the disturbed field with a good precision. For this purpose, a toroidal current in the plasma and an eddy current on a conducting wall are replaced by magnetic dipole and image magnetic dipole moments, respectively. Typical spatial structures of the disturbed field are calculated by using the dipole moments for such MHD motions as radial shift, internal tilt, external tilt, and n=2 mode deformation. Then, analytic formulas for estimating the shift distance, tilt angle, and deformation rate of the MHD motions from magnetic probe signals are derived. It is estimated from the calculations by using the dipole moments that the analytic formulas include an approximately 40% error. Two kinds of experiment are carried out to investigate the reliability of the calculations. First, a magnetic field produced by a circular current is measured in an aluminum pipe to confirm the replacement of the eddy current with the image magnetic dipole moments. The measured fields coincide well with the calculated values including the image magnetic dipole moments. Second, magnetic probe signals measured from the FRC plasma are substituted into the analytic formulas to obtain shift distance and deformation rate. The experimental results are compared to the MHD motions measured by using a radiation from the plasma. If the error included in the analytic formulas and the difference between the magnetic and optical structures in the plasma are considered, the results of the radiation measurement support well those of the magnetic analysis.

  17. Electrochemical Reduction of Ag2VP2O8 Composite Electrodes Visualized via In situ Energy Dispersive X-ray Diffraction (EDXRD). Unexpected Conductive Additive Effects

    SciTech Connect

    Kirshenbaum, Kevin C.; Bock, David C.; Zhong, Zhong; Marschilok, Amy C.; Takeuchi, Kenneth J.; Takeuchi, Esther

    2015-07-29

    In our study, we characterize the deposition of silver metal nanoparticles formed during discharge of Li/Ag2VP2O8 cells with composite cathodes containing conductive carbon additive. Using in situ energy dispersive X-ray diffraction (EDXRD) of an intact battery, the location and distribution of silver metal nanoparticles generated upon reduction-displacement deposition within an Ag2VP2O8 cathode containing a pre-existing percolation network can be observed for the first time. Our study yielded unexpected results where higher rate initial discharge generated a more effective conductive matrix. This stands in contrast to cells with cathodes with no conductive additive where a low rate initial discharge proved more effective. Our results provide evidence that using conductive additives in conjunction with an in situ reduction-displacement deposition of silver metal provides a path toward the ultimate goal of complete electrical contact and full utilization of all electroactive particles.

  18. Effects of Lithium Oxide Addition on Sintering Behavior and Electrical Conductivity of Ce0.8Gd0.2O1.9 Ceramics Prepared by Commercial Powders.

    PubMed

    Seo, Seung-Woo; Park, Min-Woo; Lee, Joo-Sin

    2016-05-01

    The densification behavior and electrical conductivity of Ce0.8Gd0.2O1.9 ceramics with lithium oxide concentrations ranging from 0 to 7 mol% were investigated. The sintered density was found to increase with increasing Li2O content up to 2 mol% and then to decrease somewhat upon further Li20 addition. Dense Ce0.8Gd0.2O1.9 ceramics with 97% of the theoretical density could be obtained by sintering the milled mixture with 2 mol% Li2O addition at 1250 degrees C for 5 h. The conductivity of the 2 mol% Li2O-added specimen showed a maximum value of 4.99 x 10(-3) Ω(-1) x cm(-1) at 700 degrees C. Pure Ce0.8Gd0.2O1.9 ceramics needed to be sintered at 1550 degrees C in order to obtain an equivalent theoretical density and conductivity. The addition of Li2O was found to promote the sintering properties and electrical conductivities of Gd2O3-doped CeO2. PMID:27483925

  19. Recognizing and Conducting Opportunistic Experiments in Education: A Guide for Policymakers and Researchers. REL 2014-037

    ERIC Educational Resources Information Center

    Resch, Alexandra; Berk, Jillian; Akers, Lauren

    2014-01-01

    An opportunistic experiment is a type of randomized controlled trial that studies the effects of a planned intervention or policy change with minimal added disruption and cost. This guide defines opportunistic experiments and provides examples, discusses issues to consider when identifying potential opportunistic experiments, and outlines the…

  20. The Extreme Conditions Beamline at PETRA III, DESY: Possibilities to conduct time resolved monochromatic diffraction experiments in dynamic and laser heated DAC

    NASA Astrophysics Data System (ADS)

    Liermann, H.-P.; Morgenroth, W.; Ehnes, A.; Berghäuser, A.; Winkler, B.; Franz, H.; Weckert, E.

    2010-03-01

    We present plans for the new Extreme Conditions Beamline at PETRA III, DESY, Germany. The beamline is being designed and built with the specific goal to explore time resolved high-pressure and -temperature x-ray diffraction experiments in the dynamic and laser heated diamond anvil cell. Within we discuss the conceptual design of the optical components and experimental setup to conduct monochromatic high-pressure powder diffraction experiments in the sub-second time regime.

  1. Effect of pore size on bone ingrowth into porous titanium implants fabricated by additive manufacturing: An in vivo experiment.

    PubMed

    Taniguchi, Naoya; Fujibayashi, Shunsuke; Takemoto, Mitsuru; Sasaki, Kiyoyuki; Otsuki, Bungo; Nakamura, Takashi; Matsushita, Tomiharu; Kokubo, Tadashi; Matsuda, Shuichi

    2016-02-01

    Selective laser melting (SLM) is an additive manufacturing technique with the ability to produce metallic scaffolds with accurately controlled pore size, porosity, and interconnectivity for orthopedic applications. However, the optimal pore structure of porous titanium manufactured by SLM remains unclear. In this study, we evaluated the effect of pore size with constant porosity on in vivo bone ingrowth in rabbits into porous titanium implants manufactured by SLM. Three porous titanium implants (with an intended porosity of 65% and pore sizes of 300, 600, and 900μm, designated the P300, P600, and P900 implants, respectively) were manufactured by SLM. A diamond lattice was adapted as the basic structure. Their porous structures were evaluated and verified using microfocus X-ray computed tomography. Their bone-implant fixation ability was evaluated by their implantation as porous-surfaced titanium plates into the cortical bone of the rabbit tibia. Bone ingrowth was evaluated by their implantation as cylindrical porous titanium implants into the cancellous bone of the rabbit femur for 2, 4, and 8weeks. The average pore sizes of the P300, P600, and P900 implants were 309, 632, and 956μm, respectively. The P600 implant demonstrated a significantly higher fixation ability at 2weeks than the other implants. After 4weeks, all models had sufficiently high fixation ability in a detaching test. Bone ingrowth into the P300 implant was lower than into the other implants at 4weeks. Because of its appropriate mechanical strength, high fixation ability, and rapid bone ingrowth, our results indicate that the pore structure of the P600 implant is a suitable porous structure for orthopedic implants manufactured by SLM. PMID:26652423

  2. Families' Experiences in Wraparound: A Qualitative Study Conceived and Conducted by Families through a Professional-Family Collaboration

    ERIC Educational Resources Information Center

    Painter, Kirstin; Allen, J. Sean; Perry, Barbara

    2011-01-01

    The purpose of this study, the Family Experience Study, was to record experiences of families not captured by standard quantitative measures utilizing open-ended questions that allowed families to tell their stories in their own words. This qualitative study was conceived and carried out by family members who received wraparound services and…

  3. "Their Stories Have Changed My Life": Clinicians' Reflections on Their Experience with and Their Motivation to Conduct Asylum Evaluations.

    PubMed

    Mishori, Ranit; Hannaford, Alisse; Mujawar, Imran; Ferdowsian, Hope; Kureshi, Sarah

    2016-02-01

    Many clinicians perform asylum evaluations yet no studies describe the motivation to perform them or their perceived rewards. The number of asylum seekers in the US is increasing and more clinicians are needed as evaluators. A survey to an asylum evaluators' network asked participants to qualitatively reflect on their experience and motivation. Answers were analyzed for themes and sentiment. Respondents cited commitment to humanistic and moral values, noted personal and family experiences, having skills, expertise, and career interests as drivers. They found the experience very rewarding personally and professionally, and in their perceived benefit to asylees. Negative sentiment was less frequent and centered on emotions related to client narratives. Process-oriented frustrations were also noted. This is the first published study describing clinicians' motivation and experience with asylum evaluations. It may illuminate clinicians' drive to volunteer, and serve as a resource for organizations for recruitment and education. PMID:25527443

  4. Training Drug Treatment Patients to Conduct Peer-Based HIV Outreach: An Ethnographic Perspective on Peers' Experiences

    PubMed Central

    Guarino, Honoria; Deren, Sherry; Mino, Milton; Kang, Sung-Yeon; Shedlin, Michele

    2010-01-01

    From 2005 to 2008, the Bienvenidos Project trained Puerto Rican patients of New York City and New Jersey methadone maintenance treatment programs to conduct peer-based community outreach to migrant Puerto Rican drug users to reduce migrants' HIV risk behaviors. Ethnographic research, including focus groups, individual interviews and observations, was conducted with a subset of the patients trained as peers (n=49; 67% male; mean age 40.3 years) to evaluate the self-perceived effects of the intervention. Results of the ethnographic component of this study are summarized. The role of ethnographic methods in implementing and evaluating this kind of intervention is also discussed. PMID:20141456

  5. Exploring electrical conductivity anomalies across the martensite transition in Fe{sub 7}Pd{sub 3} ferromagnetic shape memory alloys: Experiments and ab-initio calculations

    SciTech Connect

    Arabi-Hashemi, A.; Mayr, S. G.

    2015-03-02

    Conductivity in Fe{sub 7}Pd{sub 3} is characterized by an anomalous increase when traversing the face–centered–cubic (fcc) austenite to face–centered–tetragonal (fct) martensite transition, contrary to most other conventional and ferromagnetic shape memory alloys. Experiments on molecular– beam–epitaxy–grown single crystals indicate a resistivity change of ≈20% during the transformation on top of a quadratic temperature dependence reaching up to room temperature. The physical foundations of residual resistivity changes along the full Bain path are addressed by a Kubo– Greenwood approach within the framework of density functional theory. To do so, a concept to reliably extract the DC conductivities is proposed that yields reproducible results consistent with experiments. Finding that conductivity peaks in the fct phase, we identify a large density of states paired with high velocities at the Fermi level in the majority spin sub–bands in presence of minimum s–d electron scattering as underlying physical origin.

  6. Results from the EPL monkey-pod experiment conducted as part of the 1974 NASA/Ames shuttle CVT-2

    NASA Technical Reports Server (NTRS)

    Rahlmann, D. F.; Kodama, A. M.; Mains, R. C.; Pace, N.

    1974-01-01

    The participation of the Environmental Physiology Laboratory (EPL) in the general purpose laboratory concept verification test 3 is documented. The EPL Monkey-Pod Experiment was designed to incorporate a 10-12 kg, pig tailed monkey, Macaca nemestrina, into the pod and measure the physiological responses of the animal continuously. Four major elements comprise the EPL Monkey-Pod Experiment System: (1) a fiberglass pod containing the instrumented monkey plus feeder and watering devices, (2) an inner console containing the SKYLAB mass spectrometer with its associated valving and electronic controls, sensing, control and monitoring units for lower body negative pressure, feeder activity, waterer activity, temperatures, and gas metabolism calibration, (3) an umbilical complex comprising gas flow lines and electrical cabling between the inner and outer console and (4) an outer console in principle representing the experiment support to be provided from general spacecraft sources.

  7. Results from the EPL monkey-pod flight experiments conducted aboard the NASA/Ames CV-990, May 1976

    NASA Technical Reports Server (NTRS)

    Rahlmann, D. F.; Kodama, A. M.; Mains, R. C.; Pace, N.

    1976-01-01

    The participation of the Environmental Physiology Laboratory (EPL) in the general purpose laboratory concept verification test 3 is documented. The EPL Monkey-Pod Experiment was designed to incorporate a 10-12 kg, pig tailed monkey, Macaca nemestrina, into the pod and measure the physiological responses of the animal continously. Four major elements comprise the EPL Monkey-Pod Experiment System: (1) a fiberglass pod containing the instrumented monkey plus feeder and watering devices, (2) an inner console containing the SKYLAB mass spectrometer with its associated valving and electronic controls, sensing, control and monitoring units for lower body negative pressure, feeder activity, waterer activity, temperatures, and gas metabolism calibration, (3) an umbilical complex comprising gas flow lines and electrical cabling between the inner and outer console and (4) an outer console in principle representing the experiment support to be provided from general space craft sources.

  8. Phytoplankton responses and associated carbon cycling during shipboard carbonate chemistry manipulation experiments conducted around Northwest European shelf seas

    NASA Astrophysics Data System (ADS)

    Richier, S.; Achterberg, E. P.; Dumousseaud, C.; Poulton, A. J.; Suggett, D. J.; Tyrrell, T.; Zubkov, M. V.; Moore, C. M.

    2014-09-01

    The ongoing oceanic uptake of anthropogenic carbon dioxide (CO2) is significantly altering the carbonate chemistry of seawater, a phenomenon referred to as ocean acidification. Experimental manipulations have been increasingly used to gauge how continued ocean acidification will potentially impact marine ecosystems and their associated biogeochemical cycles in the future; however, results amongst studies, particularly when performed on natural communities, are highly variable, which may reflect community/environment-specific responses or inconsistencies in experimental approach. To investigate the potential for identification of more generic responses and greater experimentally reproducibility, we devised and implemented a series (n = 8) of short-term (2-4 days) multi-level (≥4 conditions) carbonate chemistry/nutrient manipulation experiments on a range of natural microbial communities sampled in Northwest European shelf seas. Carbonate chemistry manipulations and resulting biological responses were found to be highly reproducible within individual experiments and to a lesser extent between geographically separated experiments. Statistically robust reproducible physiological responses of phytoplankton to increasing pCO2, characterised by a suppression of net growth for small-sized cells (<10 μm), were observed in the majority of the experiments, irrespective of natural or manipulated nutrient status. Remaining between-experiment variability was potentially linked to initial community structure and/or other site-specific environmental factors. Analysis of carbon cycling within the experiments revealed the expected increased sensitivity of carbonate chemistry to biological processes at higher pCO2 and hence lower buffer capacity. The results thus emphasise how biogeochemical feedbacks may be altered in the future ocean.

  9. Carbon cycling and phytoplankton responses within highly-replicated shipboard carbonate chemistry manipulation experiments conducted around Northwest European Shelf Seas

    NASA Astrophysics Data System (ADS)

    Richier, S.; Achterberg, E. P.; Dumousseaud, C.; Poulton, A. J.; Suggett, D. J.; Tyrrell, T.; Zubkov, M. V.; Moore, C. M.

    2014-03-01

    The ongoing oceanic uptake of anthropogenic carbon dioxide (CO2) is significantly altering the carbonate chemistry of seawater, a phenomenon referred to as ocean acidification. Experimental manipulations have been increasingly used to gauge how continued ocean acidification will potentially impact marine ecosystems and their associated biogeochemical cycles in the future; however, results amongst studies, particularly when performed on natural communities, are highly variable, which in part likely reflects inconsistencies in experimental approach. To investigate the potential for identification of more generic responses and greater experimentally reproducibility, we devised and implemented a series of highly replicated (n = 8), short term (2-4 days) multi-level (≥ 4 conditions) carbonate chemistry/nutrient manipulation experiments on a range of natural microbial communities sampled in Northwest European shelf seas. Carbonate chemistry manipulations and resulting biological responses were found to be highly reproducible within individual experiments and to a lesser extent between geographically different experiments. Statistically robust reproducible physiological responses of phytoplankton to increasing pCO2, characterized by a suppression of net growth for small sized cells (< 10 μm), were observed in the majority of the experiments, irrespective of nutrient status. Remaining between-experiment variability was potentially linked to initial community structure and/or other site-specific environmental factors. Analysis of carbon cycling within the experiments revealed the expected increased sensitivity of carbonate chemistry to biological processes at higher pCO2 and hence lower buffer capacity. The results thus emphasize how biological-chemical feedbacks may be altered in the future ocean.

  10. Conducting Multi-Generational Qualitative Research in Education: An Experiment in Grounded Theory. Black Studies and Critical Thinking. Volume 5

    ERIC Educational Resources Information Center

    Collins, Donald R.

    2011-01-01

    This book outlines a methodology for viewing multiple generations of African Americans, specifically those who were called or called themselves Negro, Colored, Black, or African American (NCBAA). Within this framework, African Americans of varying ages describe their lives and educational experiences, allowing researchers to address a variety of…

  11. MyAgRecord: An Online Career Portfolio Management Tool for High School Students Conducting Supervised Agricultural Experience Programs.

    ERIC Educational Resources Information Center

    Emis, Larry; Dillingham, John

    Texas's online career portfolio management tool for high school students participating in supervised agricultural experience programs (SAEPs) was developed in 1998 by a committee of Texas high school teachers of agriscience and Texas Education Agency personnel. The career portfolio management tool reflects General Accepted Accounting Principles…

  12. Effect of volcano ash additions on nutrient concentrations, bloom dynamics and community metabolism in a short-term experiment in the NW Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Weinbauer, Markus

    2016-04-01

    Volcano ash deposition is now considered as an important source of inorganic bioavailable iron which can relieve Fe-limitation in the ocean. As volcano ash also releases PO4, a experiment was performed in the NW Mediterranean Sea to test whether volcano ash deposition can affect nutrient dynamics and bloom development in a P-limited system. In a 54h experiment, it was shown that the development of a phytoplankton bloom was not enhanced or even repressed by ash additions of 2 and 20 mg l-1, whereas higher ash concentrations (200 mg l-1) induced a phytoplankton bloom as indicated by elevated Chlorophyll-a levels. Concurrently, net community production (NCP) and gross primary production (GPP) were enhanced at T24h at the highest ash additions. The metabolic balance was roughly neutral at low or no ash additions, but shifted towards phototrophy at the highest ash additions. The data on inorganic nutrient development and release estimates from ash material assays suggest relieving of P-limitation concomitant with NO3 and silicate use from ash. The concentration of TEP increased with increasing ash levels. The abundances of the heterotrophic compartment (bacteria, viruses and ciliates) also indicated dose-dependent responses. Our data suggest that heterotrophs won the competition for inorganic nutrients at ash levels of 2 and 20 mg l-1, whereas phytoplankton won at levels of 200 mg l-1. Overall, our experiments point to a strong potential of volcano ash deposition as forcing factor for nutrient dynamics and the activity of microbial plankton in a P-limited system.

  13. Graduate Socialization in the Responsible Conduct of Research: A National Survey on the Research Ethics Training Experiences of Psychology Doctoral Students

    PubMed Central

    Fisher, Celia B.; Fried, Adam L.; Feldman, Lindsay G.

    2013-01-01

    Little is known about the mechanisms by which psychology graduate programs transmit responsible conduct of research (RCR) values. A national sample of 968 current students and recent graduates of mission-diverse doctoral psychology programs, completed a web-based survey on their research ethics challenges, perceptions of RCR mentoring and department climate, their ability to conduct research responsibility, and whether they believed psychology as a discipline promotes scientific integrity. Research experience, mentor RCR instruction and modeling, and department RCR policies predicted student RCR preparedness. Mentor RCR instruction, department RCR policies, and faculty modeling of RCR behaviors predicted confidence in the RCR integrity of the discipline. Implications for training are discussed. PMID:23641128

  14. Conducting and permeable states of cell membrane submitted to high voltage pulses: mathematical and numerical studies validated by the experiments.

    PubMed

    Leguèbe, M; Silve, A; Mir, L M; Poignard, C

    2014-11-01

    The aim of this paper is to present a new model of in vitro cell electropermeabilization, which describes separately the conducting state and the permeable state of the membrane submitted to high voltage pulses. We first derive the model based on the experimental observations and we present the numerical methods to solve the non-linear partial differential equations. We then present numerical simulations that corroborate qualitatively the experimental data dealing with the uptake of propidium iodide (PI) after millipulses. This tends to justify the validity of our modeling. Forthcoming work will be to calibrate the parameters of the model for quantitative description of the uptake. PMID:25010659

  15. X-ray absorption and reflection as probes of the GaN conduction bands: Theory and experiments

    SciTech Connect

    Lambrecht, W.R.L.; Rashkeev, S.N.; Segall, B.

    1997-04-01

    X-ray absorption measurements are a well-known probe of the unoccupied states in a material. The same information can be obtained by using glancing angle X-ray reflectivity. In spite of several existing band structure calculations of the group III nitrides and previous optical studies in UV range, a direct probe of their conduction band densities of states is of interest. The authors performed a joint experimental and theoretical investigation using both of these experimental techniques for wurtzite GaN.

  16. Nature of the band gap and origin of the conductivity of PbO2 revealed by theory and experiment.

    PubMed

    Scanlon, David O; Kehoe, Aoife B; Watson, Graeme W; Jones, Martin O; David, William I F; Payne, David J; Egdell, Russell G; Edwards, Peter P; Walsh, Aron

    2011-12-01

    Lead dioxide has been used for over a century in the lead-acid battery. Many fundamental questions concerning PbO2 remain unanswered, principally: (i) is the bulk material a metal or a semiconductor, and (ii) what is the source of the high levels of conductivity? We calculate the electronic structure and defect physics of PbO2, using a hybrid density functional, and show that it is an n-type semiconductor with a small indirect band gap of ∼0.2  eV. The origin of electron carriers in the undoped material is found to be oxygen vacancies, which forms a donor state resonant in the conduction band. A dipole-forbidden band gap combined with a large carrier induced Moss-Burstein shift results in a large effective optical band gap. The model is supported by neutron diffraction, which reveals that the oxygen sublattice is only 98.4% occupied, thus confirming oxygen substoichiometry as the electron source. PMID:22243014

  17. Nature of the Band Gap and Origin of the Conductivity of PbO2 Revealed by Theory and Experiment

    NASA Astrophysics Data System (ADS)

    Scanlon, David O.; Kehoe, Aoife B.; Watson, Graeme W.; Jones, Martin O.; David, William I. F.; Payne, David J.; Egdell, Russell G.; Edwards, Peter P.; Walsh, Aron

    2011-12-01

    Lead dioxide has been used for over a century in the lead-acid battery. Many fundamental questions concerning PbO2 remain unanswered, principally: (i) is the bulk material a metal or a semiconductor, and (ii) what is the source of the high levels of conductivity? We calculate the electronic structure and defect physics of PbO2, using a hybrid density functional, and show that it is an n-type semiconductor with a small indirect band gap of ˜0.2eV. The origin of electron carriers in the undoped material is found to be oxygen vacancies, which forms a donor state resonant in the conduction band. A dipole-forbidden band gap combined with a large carrier induced Moss-Burstein shift results in a large effective optical band gap. The model is supported by neutron diffraction, which reveals that the oxygen sublattice is only 98.4% occupied, thus confirming oxygen substoichiometry as the electron source.

  18. Strategies for Conducting Adolescent Health Research in the Clinical Setting: The Mount Sinai Adolescent Health Center HPV Experience

    PubMed Central

    Braun-Courville, Debra K.; Schlecht, Nicolas F.; Burk, Robert D.; Strickler, Howard D.; Rojas, Mary; Lorde-Rollins, Elizabeth; Nucci-Sack, Anne; Hollman, Dominic; Linares, L. Oriana; Diaz, Angela

    2013-01-01

    Background Clinical research with adolescents can be challenging due to issues of informed consent, parental involvement, institutional review board requirements, and adolescent psychosocial development. This presents a dilemma, particularly in the area of sexual health research, as adolescents are disproportionately affected by sexually transmitted infections such as human papillomavirus (HPV). To successfully conduct adolescent research in the clinical setting, one requires an awareness of state statutes regarding adolescent confidentiality and consent for medical care, and a close partnership with the IRB. Case Study In 2007, the Mount Sinai Adolescent Health Center (MSAHC) in collaboration with the Albert Einstein College of Medicine developed a longitudinal research study to examine the natural history of oral, cervical, and anal HPV in an adolescent female population engaged in high-risk sexual behaviors. We use this research project as a case study to explore the ethical, methodological, and clinical issues related to conducting adolescent health research. Summary and Conclusions Several strategies were identified to promote adolescent study participation, including: (1) building a research team that is motivated to work with adolescents; (2) combining research and patient care visits to avoid duplication of services; and (3) establishing a personalized communication network with participants. Using these methods, adolescent sexual health research can successfully be integrated into the clinical setting. While retaining a prospective cohort of adolescents has its challenges, a persistent and multi-disciplinary approach can help improve recruitment, sustain participation, and acquire critical data that will lead to improved healthcare knowledge applicable to understudied populations of adolescents. PMID:24332677

  19. The In-Space Soldering Investigation: To Date Analysis of Experiments Conducted on the International Space Station

    NASA Technical Reports Server (NTRS)

    Grugel, Richard N.; Gillies, D. C.; Hua, F.; Anilkumar, A.

    2006-01-01

    Soldering is a well established joining and repair process that is of particular importance in the electronics industry. Still, internal solder joint defects such as porosity are prevalent and compromise desired properties such as electrical/thermal conductivity and fatigue strength. Soldering equipment resides aboard the International Space Station (ISS) and will likely accompany Exploration Missions during transit to, as well as on, the moon and Mars. Unfortunately, detrimental porosity appears to be enhanced in lower gravity environments. To this end, the In-Space Soldering Investigation (ISSI) is being conducted in the Microgravity Workbench Area (MWA) aboard the ISS as "Saturday Science" with the goal of promoting our understanding of joining techniques, shape equilibrium, wetting phenomena, and microstructural development in a microgravity environment. The work presented here will focus on direct observation of melting dynamics and shape determination in comparison to ground-based samples, with implications made to processing in other low-gravity environments. Unexpected convection effects, masked on Earth, will also be shown as well as the value of the ISS as a research platform in support of Exploration Missions.

  20. Tracking molecular resonance forms of donor–acceptor push–pull molecules by single-molecule conductance experiments

    PubMed Central

    Lissau, Henriette; Frisenda, Riccardo; Olsen, Stine T.; Jevric, Martyn; Parker, Christian R.; Kadziola, Anders; Hansen, Thorsten; van der Zant, Herre S. J.; Brøndsted Nielsen, Mogens; Mikkelsen, Kurt V.

    2015-01-01

    The ability of molecules to change colour on account of changes in solvent polarity is known as solvatochromism and used spectroscopically to characterize charge-transfer transitions in donor–acceptor molecules. Here we report that donor–acceptor-substituted molecular wires also exhibit distinct properties in single-molecule electronics under the influence of a bias voltage, but in absence of solvent. Two oligo(phenyleneethynylene) wires with donor–acceptor substitution on the central ring (cruciform-like) exhibit remarkably broad conductance peaks measured by the mechanically controlled break-junction technique with gold contacts, in contrast to the sharp peak of simpler molecules. From a theoretical analysis, we explain this by different degrees of charge delocalization and hence cross-conjugation at the central ring. Thus, small variations in the local environment promote the quinoid resonance form (off), the linearly conjugated (on) or any form in between. This shows how the conductance of donor–acceptor cruciforms is tuned by small changes in the environment. PMID:26667583

  1. Assessing traumatic experiences in screening for PTSD in substance use disorder patients: what is the gain in addition to PTSD symptoms?

    PubMed

    Kok, Tim; de Haan, Hein; van der Meer, Margreet; Najavits, Lisa; de Jong, Cor

    2015-03-30

    Traumatic experiences have been linked with substance use disorders (SUD) and may be an important factor in the perpetuation of SUD, even in the absence of posttraumatic stress disorder (PTSD) symptoms. The purpose of the current study was to examine the relationship between childhood trauma and substance use severity in 192 SUD inpatients. Childhood trauma was assessed using the Traumatic Experiences Checklist (TEC). With variables derived from this measure in addition to PTSD symptoms, two regression models were created with alcohol use or drug use severity as dependent variables. Alcohol severity was explained by PTSD symptoms as well as the age of trauma. Drug severity was explained solely by PTSD symptoms. The clinical value of assessing childhood trauma in determining the addiction severity appears to be limited in comparison with PTSD symptoms. PMID:25687377

  2. Micron-Size Zero-Valent Iron Emplacement in Porous Media Using Polymer Additives: Column and Flow Cell Ex-periments

    SciTech Connect

    Oostrom, Mart; Wietsma, Thomas W.; Covert, Matthew A.; Vermeul, Vince R.

    2006-03-20

    At the Hanford Site, an extensive In Situ Redox Manipulation (ISRM) permeable reactive barrier was installed to prevent chromate from reaching the Columbia River. However, chromium has been detected in several wells, indicating a premature loss of the reductive capacity in the aquifer. Laboratory experiments have been conducted to investigate whether barrier reductive capacity can be enhanced by adding micron-scale zero-valent iron to the high-permeability zones within the aquifer using shear-thinning fluids containing polymers. Porous media were packed in a wedge-shaped flow cell to create either a heterogeneous layered system with a high-permeability zone between two low-permeability zones or a high-permeability channel sur-rounded by low-permeability materials. The injection flow rate, polymer type, polymer concentration, and injected pore volumes were determined based on preliminary short- and long-column experiments. The flow cell experiments indicated that iron concentration enhancements of at least 0.6% (w/w) could be obtained using moderate flow rates and injection of 30 pore volumes. The 0.6% amended Fe0 concentration would provide approximately 20 times the average reductive capacity that is provided by the dithionite-reduced iron in the ISRM barrier. Calculations show that a 1-m-long Fe0 amended zone with an average concentration of 0.6% w/w iron subject to a groundwater velocity of 1 m/day will have an estimated longevity of 7.2 years.

  3. Response of aboveground biomass and diversity to nitrogen addition – a five-year experiment in semi-arid grassland of Inner Mongolia, China

    PubMed Central

    He, Kejian; Qi, Yu; Huang, Yongmei; Chen, Huiying; Sheng, Zhilu; Xu, Xia; Duan, Lei

    2016-01-01

    Understanding the response of the plant community to increasing nitrogen (N) deposition is helpful for improving pasture management in semi-arid areas. We implemented a 5-year N addition experiment in a Stipa krylovii steppe of Inner Mongolia, northern China. The aboveground biomass (AGB) and species richness were measured annually. Along with the N addition levels, the species richness declined significantly, and the species composition changed noticeably. However, the total AGB did not exhibit a noticeable increase. We found that compensatory effects of the AGB occurred not only between the grasses and the forbs but also among Gramineae species. The plant responses to N addition, from the community to species level, lessened in dry years compared to wet or normal years. The N addition intensified the reduction of community productivity in dry years. Our study indicated that the compensatory effects of the AGB among the species sustained the stability of grassland productivity. However, biodiversity loss resulting from increasing N deposition might lead the semi-arid grassland ecosystem to be unsustainable, especially in dry years. PMID:27573360

  4. Response of aboveground biomass and diversity to nitrogen addition - a five-year experiment in semi-arid grassland of Inner Mongolia, China.

    PubMed

    He, Kejian; Qi, Yu; Huang, Yongmei; Chen, Huiying; Sheng, Zhilu; Xu, Xia; Duan, Lei

    2016-01-01

    Understanding the response of the plant community to increasing nitrogen (N) deposition is helpful for improving pasture management in semi-arid areas. We implemented a 5-year N addition experiment in a Stipa krylovii steppe of Inner Mongolia, northern China. The aboveground biomass (AGB) and species richness were measured annually. Along with the N addition levels, the species richness declined significantly, and the species composition changed noticeably. However, the total AGB did not exhibit a noticeable increase. We found that compensatory effects of the AGB occurred not only between the grasses and the forbs but also among Gramineae species. The plant responses to N addition, from the community to species level, lessened in dry years compared to wet or normal years. The N addition intensified the reduction of community productivity in dry years. Our study indicated that the compensatory effects of the AGB among the species sustained the stability of grassland productivity. However, biodiversity loss resulting from increasing N deposition might lead the semi-arid grassland ecosystem to be unsustainable, especially in dry years. PMID:27573360

  5. Third and Final Shuttle Mission of the Isothermal Dendritic Growth Experiment Conducted: Highest Supercooling Ever Recorded Achieved

    NASA Technical Reports Server (NTRS)

    Glicksman, Martin E.; Malarik, Diane C.

    1999-01-01

    Dendrites describe the treelike crystal morphology commonly assumed in metals and alloys that freeze from supercooled or supersaturated melts. There remains a high level of engineering interest in dendritic solidification because the size, shape, and orientation of the dendrites determine the final microstructure of a material. It is the microstructure that then determines the physical properties of cast or welded products. Although it is well known that dendritic growth is controlled by the transport of latent heat from the moving solid-liquid interface, an accurate and predictive model has not yet been developed. The effects of gravity-induced convection on the transfer of heat from the interface have prevented adequate testing, under terrestrial conditions, of solidification models. The Isothermal Dendritic Growth Experiment (IDGE) constituted a series of three microgravity experiments flown aboard the Space Shuttle Columbia. The apparatus was used to grow and record dendrite solidification in the absence of gravity-induced convective heat transfer, thereby producing a wealth of benchmark-quality data for testing solidification models and theories.

  6. Thermal mathematical model correlation through genetic algorithms of an experiment conducted on board the International Space Station

    NASA Astrophysics Data System (ADS)

    Garmendia, Iñaki; Anglada, Eva

    2016-05-01

    Genetic algorithms have been used for matching temperature values generated using thermal mathematical models against actual temperatures measured in thermal testing of spacecrafts and space instruments. Up to now, results for small models have been very encouraging. This work will examine the correlation of a small-medium size model, whose thermal test results were available, by means of genetic algorithms. The thermal mathematical model reviewed herein corresponds to Tribolab, a materials experiment deployed on board the International Space Station and subjected to preflight thermal testing. This paper will also discuss in great detail the influence of both the number of reference temperatures available and the number of thermal parameters included in the correlation, taking into account the presence of heat sources and the maximum range of temperature mismatch. Conclusions and recommendations for the thermal test design will be provided, as well as some indications for future improvements.

  7. Partnerships for the Design, Conduct, and Analysis of Effectiveness, and Implementation Research: Experiences of the Prevention Science and Methodology Group

    PubMed Central

    Brown, C. Hendricks; Kellam, Sheppard G.; Kaupert, Sheila; Muthén, Bengt O.; Wang, Wei; Muthén, Linda K.; Chamberlain, Patricia; PoVey, Craig L.; Cady, Rick; Valente, Thomas W.; Ogihara, Mitsunori; Prado, Guillermo J.; Pantin, Hilda M.; Gallo, Carlos G.; Szapocznik, José; Czaja, Sara J.; McManus, John W.

    2012-01-01

    What progress prevention research has made comes through strategic partnerships with communities and institutions that host this research, as well as professional and practice networks that facilitate the diffusion of knowledge about prevention. We discuss partnership issues related to the design, analysis, and implementation of prevention research and especially how rigorous designs, including random assignment, get resolved through a partnership between community stakeholders, institutions, and researchers. These partnerships shape not only study design, but they determine the data that can be collected and how results and new methods are disseminated. We also examine a second type of partnership to improve the implementation of effective prevention programs into practice. We draw on social networks to studying partnership formation and function. The experience of the Prevention Science and Methodology Group, which itself is a networked partnership between scientists and methodologists, is highlighted. PMID:22160786

  8. Partnerships for the design, conduct, and analysis of effectiveness, and implementation research: experiences of the prevention science and methodology group.

    PubMed

    Brown, C Hendricks; Kellam, Sheppard G; Kaupert, Sheila; Muthén, Bengt O; Wang, Wei; Muthén, Linda K; Chamberlain, Patricia; PoVey, Craig L; Cady, Rick; Valente, Thomas W; Ogihara, Mitsunori; Prado, Guillermo J; Pantin, Hilda M; Gallo, Carlos G; Szapocznik, José; Czaja, Sara J; McManus, John W

    2012-07-01

    What progress prevention research has made comes through strategic partnerships with communities and institutions that host this research, as well as professional and practice networks that facilitate the diffusion of knowledge about prevention. We discuss partnership issues related to the design, analysis, and implementation of prevention research and especially how rigorous designs, including random assignment, get resolved through a partnership between community stakeholders, institutions, and researchers. These partnerships shape not only study design, but they determine the data that can be collected and how results and new methods are disseminated. We also examine a second type of partnership to improve the implementation of effective prevention programs into practice. We draw on social networks to studying partnership formation and function. The experience of the Prevention Science and Methodology Group, which itself is a networked partnership between scientists and methodologists, is highlighted. PMID:22160786

  9. Upper atmosphere wind and temperature structure at sonmiani derived from the rocket grenade experiments conducted during 1965 - 1967

    NASA Technical Reports Server (NTRS)

    Rahmatullah, M.

    1972-01-01

    The grenade-TMA firing conducted in 1965-1967 bring out the following important features regarding the stratospheric circulation in the subtropics: (1) The temperature pattern during the month of March/April at Sonmiani is characterized by higher temperature than the corresponding CIRA 1965 value. (2) Double maxima in temperature has often been observed during spring. (3) In March the zonal wind is predominantly westerly reaching a maximum value of about 45 m/s at 55 km. (4) The meridional component exhibits oscillatory character between 45 and 60 kms. (5) The change from winter westerlies to summer easterlies first occurred around 50 km during April and gradually affected higher levels as the month progressed. (6) The height of the principal maxima at Sonmiani is located at 105 + or - 5 km. In autumn the wind at the principal maxima is below 100 m/s and is directed to NW, in spring it is of the order of 118 m/s but directed to E or NE.

  10. Preliminary results of vibrator-aided experiments in non-linear seismology conducted at Uetze, F.R.G.

    NASA Astrophysics Data System (ADS)

    Dimitriu, Petros P.

    1990-10-01

    Following acoustics and largely thanks to the pioneering work of a group of Soviet geophysicists, the study of non-linear elastic properties and their effects is becoming an active field of research in geophysics. The research so far has produced a substantial body of evidence indicating that earth materials, from soils to crystalline rocks, are much more non-linear than is commonly believed and certainly far more non-linear than the materials usually used and studied in acoustics. But although most of the evidence comes from vibrator-aided experiments, apparently best suited for investigating the non-linearity of the geophysical medium owing to the ability of modern vibrators to generate seismic signals of prescribed form, the absence of a standard experimental technique makes it difficult to estimate and compare the various results, particularly in view of the considerable non-linearity of the source (vibrator-ground system) itself. The aim of the present vibrator-aided experiments was to try to confirm certain results in non-linear seismology, particularly the effects of harmonic generation and non-linear interaction in vibrator-induced sinusoidal seismic waves, by using an experimental method designed to enable one to discriminate between source, near-field and far-field non-linear effects. In the experiments, two identical prospecting vibrators, installed on the ground surface some 16 m apart, were driven in the harmonic regime separately and simultaneously (tests on non-linear evolution and interaction), a wide range of excitation frequencies and amplitudes being covered, and the resulting ground-surface motion was picked up by an array consisting of 48 groups of 12 vertical geophones-velocimeters and recorded, in multiplex form, by a prospecting seismic station. Tests were made first for short and intermediate source-receiver distances (near field, distance range covered 0-200 m, 5-m spacing of geophone groups), then for large distances (far field, range 1

  11. NASA's Rodent Research Project: Validation of Flight Hardware, Operations and Science Capabilities for Conducting Long Duration Experiments in Space

    NASA Technical Reports Server (NTRS)

    Choi, S. Y.; Beegle, J. E.; Wigley, C. L.; Pletcher, D.; Globus, R. K.

    2015-01-01

    Research using rodents is an essential tool for advancing biomedical research on Earth and in space. Rodent Research (RR)-1 was conducted to validate flight hardware, operations, and science capabilities that were developed at the NASA Ames Research Center. Twenty C57BL/6J adult female mice were launched on Sept 21, 2014 in a Dragon Capsule (SpaceX-4), then transferred to the ISS for a total time of 21-22 days (10 commercial mice) or 37 (10 validation mice). Tissues collected on-orbit were either rapidly frozen or preserved in RNA later at less than or equal to -80 C (n=2/group) until their return to Earth. Remaining carcasses were rapidly frozen for dissection post-flight. The three controls groups at Kennedy Space Center consisted of: Basal mice euthanized at the time of launch, Vivarium controls, housed in standard cages, and Ground Controls (GC), housed in flight hardware within an environmental chamber. FLT mice appeared more physically active on-orbit than GC, and behavior analysis are in progress. Upon return to Earth, there were no differences in body weights between FLT and GC at the end of the 37 days in space. RNA was of high quality (RIN greater than 8.5). Liver enzyme activity levels of FLT mice and all control mice were similar in magnitude to those of the samples that were optimally processed in the laboratory. Liver samples collected from the intact frozen FLT carcasses had RNA RIN of 7.27 +/- 0.52, which was lower than that of the samples processed on-orbit, but similar to those obtained from the control group intact carcasses. Nonetheless, the RNA samples from the intact carcasses were acceptable for the most demanding transcriptomic analyses. Adrenal glands, thymus and spleen (organs associated with stress response) showed no significant difference in weights between FLT and GC. Enzymatic activity was also not significantly different. Over 3,000 tissues collected from the four groups of mice have become available for the Biospecimen Sharing

  12. Variable conductance heat pipe technology

    NASA Technical Reports Server (NTRS)

    Marcus, B. D.; Edwards, D. K.; Anderson, W. T.

    1973-01-01

    Research and development programs in variable conductance heat pipe technology were conducted. The treatment has been comprehensive, involving theoretical and/or experimental studies in hydrostatics, hydrodynamics, heat transfer into and out of the pipe, fluid selection, and materials compatibility, in addition to the principal subject of variable conductance control techniques. Efforts were not limited to analytical work and laboratory experimentation, but extended to the development, fabrication and test of spacecraft hardware, culminating in the successful flight of the Ames Heat Pipe Experiment on the OAO-C spacecraft.

  13. Chemical Results of Laboratory Dry/Rewet Experiments Conducted on Wetland Soils from Two Sites in the Everglades, Florida

    USGS Publications Warehouse

    Orem, William H.

    2008-01-01

    Drought and fire are natural environmental factors that have historically impacted and shaped the Everglades ecosystem. For example, drought and fire help to maintain the existing ecosystem biotic assemblage by periodically eradicating invading flora not adapted to living with this normal aspect of Everglades' ecology. Flora native to the Everglades are adapted to withstand normal drought cycles and all but the most intense fire conditions that burn into the peat substrate. Remobilization of nutrients and other elements from wetland soil following drought/fire and rewetting may actually stimulate plant re-growth, assisting in the recovery of the ecosystem from these events, and play a role in maintaining the geochemical balance of the ecosystem. Although drought/fire cycles occur naturally in the Everglades' ecosystem, the frequency, intensity, and duration of these events have been altered by anthropogenic activities. The hydrology of the ecosystem has been changed by the construction of water management structures starting around 1900 and continuing through the 1970s. These structures include canals, levees, and pumping stations around Lake Okeechobee and within the Everglades. In addition, water management practices have preferentially moved water toward agricultural and urban areas and away from the Everglades during periods of low rainfall. One result of these practices has been more severe drought and fire cycles within the ecosystem compared to pre-development activity. A major goal of restoration efforts in the Everglades is to restore a more natural flow of water into the ecosystem to alleviate some of the extreme drought and fire conditions witnessed during the past several decades.

  14. Polygenic inheritance of Tourette syndrome, stuttering, attention deficit hyperactivity, conduct, and oppositional defiant disorder: The additive and subtractive effect of the three dopaminergic genes - DRD2, D{beta}H, and DAT1

    SciTech Connect

    Comings, D.E.; Wu, S.; Chiu, C.; Ring, R.H.; Gade, R.; Ahn, C.; Dietz, G.; Muhleman, D.

    1996-05-31

    Polymorphisms of three different dopaminergic genes, dopamine D{sub 2} receptor (DRD2), dopamine {beta}-hydroxylase (D{beta}H), and dopamine transporter (DAT1), were examined in Tourette syndrome (TS) probands, their relatives, and controls. Each gene individually showed a significant correlation with various behavioral variables in these subjects. The additive and subtractive effects of the three genes were examined by genotyping all three genes in the same set of subjects. For 9 of 20 TS associated comorbid behaviors there was a significant linear association between the degree of loading for markers of three genes and the mean behavior scores. The behavior variables showing the significant associations were, in order, attention deficit hyperactivity disorder (ADHD), stuttering, oppositional defiant, tics, conduct, obsessive-compulsive, mania, alcohol abuse, and general anxiety - behaviors that constitute the most overt clinical aspects of TS. For 16 of the 20 behavior scores there was a linear progressive decrease in the mean score with progressively lesser loading for the three gene markers. These results suggest that TS, ADHD, stuttering, oppositional defiant and conduct disorder, and other behaviors associated with TS, are polygenic, due in part to these three dopaminergic genes, and that the genetics of other polygenic psychiatric disorders may be deciphered using this technique. 144 refs., 2 figs., 13 tabs.

  15. A Proposed Instructional Theory for Integer Addition and Subtraction

    ERIC Educational Resources Information Center

    Stephan, Michelle; Akyuz, Didem

    2012-01-01

    This article presents the results of a 7th-grade classroom teaching experiment that supported students' understanding of integer addition and subtraction. The experiment was conducted to test and revise a hypothetical learning trajectory so as to propose a potential instructional theory for integer addition and subtraction. The instructional…

  16. Seismic reflection data imaging and interpretation from Braniewo2014 experiment using additional wide-angle refraction and reflection and well-logs data

    NASA Astrophysics Data System (ADS)

    Trzeciak, Maciej; Majdański, Mariusz; Białas, Sebastian; Gaczyński, Edward; Maksym, Andrzej

    2015-04-01

    Braniewo2014 reflection and refraction experiment was realized in cooperation between Polish Oil and Gas Company (PGNiG) and the Institute of Geophysics (IGF), Polish Academy of Sciences, near the locality of Braniewo in northern Poland. PGNiG realized a 20-km-long reflection profile, using vibroseis and dynamite shooting; the aim of the reflection survey was to characterise Silurian shale gas reservoir. IGF deployed 59 seismic stations along this profile and registered additional full-spread wide-angle refraction and reflection data, with offsets up to 12 km; maximum offsets from the seismic reflection survey was 3 km. To improve the velocity information two velocity logs from near deep boreholes were used. The main goal of the joint reflection-refraction interpretation was to find relations between velocity field from reflection velocity analysis and refraction tomography, and to build a velocity model which would be consistent for both, reflection and refraction, datasets. In this paper we present imaging results and velocity models from Braniewo2014 experiment and the methodology we used.

  17. Food additives

    MedlinePlus

    Food additives are substances that become part of a food product when they are added during the processing or making of that food. "Direct" food additives are often added during processing to: Add nutrients ...

  18. T cell regulation in microgravity - The current knowledge from in vitro experiments conducted in space, parabolic flights and ground-based facilities

    NASA Astrophysics Data System (ADS)

    Hauschild, Swantje; Tauber, Svantje; Lauber, Beatrice; Thiel, Cora S.; Layer, Liliana E.; Ullrich, Oliver

    2014-11-01

    Dating back to the Apollo and Skylab missions, it has been reported that astronauts suffered from bacterial and viral infections during space flight or after returning to Earth. Blood analyses revealed strongly reduced capability of human lymphocytes to become active upon mitogenic stimulation. Since then, a large number of in vitro studies on human immune cells have been conducted in space, in parabolic flights, and in ground-based facilities. It became obvious that microgravity affects cell morphology and important cellular functions. Observed changes include cell proliferation, the cytoskeleton, signal transduction and gene expression. This review gives an overview of the current knowledge of T cell regulation under altered gravity conditions obtained by in vitro studies with special emphasis on the cell culture conditions used. We propose that future in vitro experiments should follow rigorous standardized cell culture conditions, which allows better comparison of the results obtained in different flight- and ground-based experiment platforms.

  19. Experiments Conducted Aboard the International Space Station: The Pore Formation and Mobility Investigation (PFMI) and the In-Space Soldering Investigation (ISSI): A Current Study of Results

    NASA Technical Reports Server (NTRS)

    Grugel, R. N.; Luz, P.; Smith, G. A.; Spivey, R.; Jeter, L.; Gillies, D. C> ; Hua, F.; Anilkumar, A. V.

    2006-01-01

    Experiments in support of the Pore Formation and Mobility Investigation (PFMI) and the In-Space Soldering Investigation (ISSI) were conducted aboard the International Space Station (ISS) with the goal of promoting our fundamental understanding of melting dynamics , solidification phenomena, and defect generation during materials processing in a microgravity environment. Through the course of many experiments a number of observations, expected and unexpected, have been directly made. These include gradient-driven bubble migration, thermocapillary flow, and novel microstructural development. The experimental results are presented and found to be in good agreement with models pertinent to a microgravity environment. Based on the space station results, and noting the futility of duplicating them in Earth s unit-gravity environment, attention is drawn to the role ISS experimentslhardware can play to provide insight to potential materials processing techniques and/or repair scenarios that might arise during long duration space transport and/or on the lunar/Mars surface.

  20. Soil microbial biomass and community structure affected by repeated additions of sewage sludge in four Swedish long-term field experiments

    NASA Astrophysics Data System (ADS)

    Börjesson, G.; Kätterer, T.; Kirchmann, H.

    2012-04-01

    Soil organic matter is a key attribute of soil fertility. The pool of soil organic C can be increased, either by mineral fertilisers or by adding organic amendments such as sewage sludge. Sewage sludge has positive effects on agricultural soils through the supply of organic matter and essential plant nutrients, but sludge may also contain unwanted heavy metals, xenobiotic substances and pathogens. One obvious effect of long-term sewage sludge addition is a decrease in soil pH, caused by N mineralisation followed by nitrification, sulphate formation and presence of organic acids with the organic matter added. The objective of this study was to investigate the effect of sewage sludge on the microbial biomass and community structure. Materials and methods We analysed soil samples from four sites where sewage sludge has been repeatedly applied in long-term field experiments situated in different parts of Sweden; Ultuna (59°49'N, 17°39'E, started 1956), Lanna (58°21'N, 13°06'E, started 1997-98), Petersborg (55°32'N, 13°00'E, started 1981) and Igelösa (55°45'N, 13°18'E, started 1981). In these four experiments, at least one sewage sludge treatment is included in the experimental design. In the Ultuna experiment, all organic fertilisers, including sewage sludge, are applied every second year, corresponding to 4 ton C ha-1. The Lanna experiment has a similar design, with 8 ton dry matter ha-1 applied every second year. Lanna also has an additional treatment in which metal salts (Cd, Cu, Ni and Zn) are added together with sewage sludge. At Petersborg and Igelösa, two levels of sewage sludge (4 or 12 ton dry matter ha-1 every 4th year) are compared with three levels of NPK fertiliser (0 N, ½ normal N and normal N). Topsoil samples (0-20 cm depth) from the four sites were analysed for total C, total N, pH and PLFAs (phospholipid fatty acids). In addition, crop yields were recorded. Results At all four sites, sewage sludge has had a positive effect on crop yields

  1. Food additives

    PubMed Central

    Spencer, Michael

    1974-01-01

    Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

  2. The Role of Patients’ Age on Their Preferences for Choosing Additional Blood Pressure-Lowering Drugs: A Discrete Choice Experiment in Patients with Diabetes

    PubMed Central

    de Vries, Sieta T.; de Vries, Folgerdiena M.; Dekker, Thijs; Haaijer-Ruskamp, Flora M.; de Zeeuw, Dick; Ranchor, Adelita V.; Denig, Petra

    2015-01-01

    Objectives To assess whether patients’ willingness to add a blood pressure-lowering drug and the importance they attach to specific treatment characteristics differ among age groups in patients with type 2 diabetes. Materials and Methods Patients being prescribed at least an oral glucose-lowering and a blood pressure-lowering drug completed a questionnaire including a discrete choice experiment. This experiment contained choice sets with hypothetical blood pressure-lowering drugs and a no additional drug alternative, which differed in their characteristics (i.e. effects and intake moments). Differences in willingness to add a drug were compared between patients <75 years (non-aged) and ≥75 years (aged) using Pearson χ2-tests. Multinomial logit models were used to assess and compare the importance attached to the characteristics. Results Of the 161 patients who completed the questionnaire, 151 (72%) could be included in the analyses (mean age 68 years; 42% female). Aged patients were less willing to add a drug than non-aged patients (67% versus 84% respectively; P = 0.017). In both age groups, the effect on blood pressure was most important for choosing a drug, followed by the risk of adverse drug events and the risk of death. The effect on limitations due to stroke was only significant in the non-aged group. The effect on blood pressure was slightly more important in the non-aged than the aged group (P = 0.043). Conclusions Aged patients appear less willing to add a preventive drug than non-aged patients. The importance attached to various treatment characteristics does not seem to differ much among age groups. PMID:26445349

  3. Metabolic and cardiovascular adaptation, monkey. NASA SMD 3, project 76, experiment 44 conducted at NASA/JSC, 14-25 May 1977

    NASA Technical Reports Server (NTRS)

    Pace, N.; Rahlmann, D. F.; Mains, R. C.; Kodama, A. M.; Mccutcheon, E. P.

    1977-01-01

    The biomedical results from an experiment on a monkey subjected to space flight conditions are reported. A background history of the development and testing of an experiment system designed to permit measurement of physiological parameters in subhuman primates during continuous, comfortable, couch restraint for periods of up to 30 days is reviewed. Of major importance in the experimental design of the system was the use of a fiberglass pod, which could be sealed and subdivided into upper and lower parts, to monitor and control the physiological responses for various parts of the animal's body. The experiment was conducted within the Spacelab Simulator for a period of 11 days. Data recorded includes: Spacelab Simulator cabin temperature; ventilation rate; pod internal temperature; fraction percent oxygen; fraction percent carbon dioxide; oxygen consumption rate; carbon dioxide production rate; respiratory quotient; intrathoracic temperature; heart rate; mean aortic pressure; mean ventricular pressure; diurnal variation of parameters measured; comparison of mean preflight, flight, and postflight values of the parameters measured; and correlation matrix for the parameters measured.

  4. Food additives.

    PubMed

    Berglund, F

    1978-01-01

    The use of additives to food fulfils many purposes, as shown by the index issued by the Codex Committee on Food Additives: Acids, bases and salts; Preservatives, Antioxidants and antioxidant synergists; Anticaking agents; Colours; Emulfifiers; Thickening agents; Flour-treatment agents; Extraction solvents; Carrier solvents; Flavours (synthetic); Flavour enhancers; Non-nutritive sweeteners; Processing aids; Enzyme preparations. Many additives occur naturally in foods, but this does not exclude toxicity at higher levels. Some food additives are nutrients, or even essential nutritents, e.g. NaCl. Examples are known of food additives causing toxicity in man even when used according to regulations, e.g. cobalt in beer. In other instances, poisoning has been due to carry-over, e.g. by nitrate in cheese whey - when used for artificial feed for infants. Poisonings also occur as the result of the permitted substance being added at too high levels, by accident or carelessness, e.g. nitrite in fish. Finally, there are examples of hypersensitivity to food additives, e.g. to tartrazine and other food colours. The toxicological evaluation, based on animal feeding studies, may be complicated by impurities, e.g. orthotoluene-sulfonamide in saccharin; by transformation or disappearance of the additive in food processing in storage, e.g. bisulfite in raisins; by reaction products with food constituents, e.g. formation of ethylurethane from diethyl pyrocarbonate; by metabolic transformation products, e.g. formation in the gut of cyclohexylamine from cyclamate. Metabolic end products may differ in experimental animals and in man: guanylic acid and inosinic acid are metabolized to allantoin in the rat but to uric acid in man. The magnitude of the safety margin in man of the Acceptable Daily Intake (ADI) is not identical to the "safety factor" used when calculating the ADI. The symptoms of Chinese Restaurant Syndrome, although not hazardous, furthermore illustrate that the whole ADI

  5. Addition of trim coils to the Tandem Mirror Experiment Upgrade (TMX-U) magnet system to improve the magnetic field mapping

    SciTech Connect

    Wong, R.L.; Pedrotti, L.R.; Baldwin, D.E.; Hibbs, S.M.; Hill, D.N.; Hornady, R.H.; Jackson, M.C.

    1985-11-14

    The mapping of the magnetic flux bundle from the center cell to the Plasma Potential Control plates (PPC) on the end fan of the Tandem Mirror Experiment Upgrade (TMX-U), was improved by the addition of trim coils (12,000 amp-turns) on each side of each end fan next to the pump beam magnetic shields. The coils' axes are oriented perpendicular to the machine centerline. These coils made the necessary corrections to the field-line mapping, while keeping the field in the nearby pump beam magnetic shield below the saturation threshold. This paper briefly describes the problem, discusses the design as it evolved, and presents the results of the field testing. The disturbance to the field mapping and the appropriate corrections were determined using the code GFUN (a three dimensional electromagnetic field analysis code that includes the presence of permeable materials). The racetrack-shaped coils have dimensions of 1.5 feet by 3 feet and are powered by a renovated 600 kW Bart-Messing power supply controlled by the machine's magnet control system. The magnets were fabricated from polyimide-coated magnet wire. They are rated to 200/sup 0/C, although in pulsed operation they rise only a few degrees centigrade. The coils are placed outside of the vacuum system, and thus are considerably simpler than the other machine magnets. The restraints are designed to withstand a force of 1000 pounds per coil and a turning moment of 1000 foot pounds. The calculated field strengths were verified on the machine by inserting a Hall probe along the axis. The perturbations to the neutral beam magnetic shields were also measured. A brief description of the improvement in the machine performance is also included.

  6. Simulating heat addition via mass addition in constant area compressible flows

    NASA Astrophysics Data System (ADS)

    Heiser, W. H.; McClure, W. B.; Wood, C. W.

    1995-01-01

    A study conducted demonstrated the striking similarity between the influence of heat addition and mass addition on compressible flows. These results encourage the belief that relatively modest laboratory experiments employing mass addition can be devised that will reproduce the leading phenomena of heat addition, such as the axial variation of properties, choking, and wall-boundary-layer separation. These suggest that some aspects of the complex behavior of dual-mode ramjet/scramjet combustors could be experimentally evaluated or demonstrated by replacing combustion with less expensive, more easily controlled, and safer mass addition.

  7. Surface Conductive Glass.

    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)

  8. Potlining Additives

    SciTech Connect

    Rudolf Keller

    2004-08-10

    In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

  9. Phosphazene additives

    SciTech Connect

    Harrup, Mason K; Rollins, Harry W

    2013-11-26

    An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

  10. Lateral spike conduction velocity in the visual cortex affects spatial range of synchronization and receptive field size without visual experience: a learning model with spiking neurons.

    PubMed

    Saam, M; Eckhorn, R

    2000-07-01

    Classical receptive fields (cRF) increase in size from the retina to higher visual centers. The present work shows how temporal properties, in particular lateral spike velocity and spike input correlation, can affect cRF size and position without visual experience. We demonstrate how these properties are related to the spatial range of cortical synchronization if Hebbian learning dominates early development. For this, a largely reduced model of two successive levels of the visual cortex is developed (e.g., areas V1 and V2). It consists of retinotopic networks of spiking neurons with constant spike velocity in lateral connections. Feedforward connections between level 1 and 2 are additive and determine cRF size and shape, while lateral connections within level 1 are modulatory and affect the cortical range of synchronization. Input during development is mimicked by spike trains with spatially homogeneous properties and a confined temporal correlation width. During learning, the homogeneous lateral coupling shrinks to limited coupling structures defining synchronization and related association fields (AF). The size of level-1 synchronization fields determines the lateral coupling range of developing level-1-to-2 connections and, thus, the size of level-2 cRFs, even if the feedforward connections have distance-independent delays. AFs and cRFs increase with spike velocity in the lateral network and temporal correlation width of the input. Our results suggest that AF size of V1 and cRF size of V2 neurons are confined during learning by the temporal width of input correlations and the spike velocity in lateral connections without the need of visual experience. During learning from visual experience, a similar influence of AF size on the cRF size may be operative at successive levels of processing, including other parts of the visual system. PMID:10933233

  11. Multiple pulse-heating experiments with different current to determine total emissivity, heat capacity, and electrical resistivity of electrically conductive materials at high temperatures.

    PubMed

    Watanabe, Hiromichi; Yamashita, Yuichiro

    2012-01-01

    A modified pulse-heating method is proposed to improve the accuracy of measurement of the hemispherical total emissivity, specific heat capacity, and electrical resistivity of electrically conductive materials at high temperatures. The proposed method is based on the analysis of a series of rapid resistive self-heating experiments on a sample heated at different temperature rates. The method is used to measure the three properties of the IG-110 grade of isotropic graphite at temperatures from 850 to 1800 K. The problem of the extrinsic heating-rate effect, which reduces the accuracy of the measurements, is successfully mitigated by compensating for the generally neglected experimental error associated with the electrical measurands (current and voltage). The results obtained by the proposed method can be validated by the linearity of measured quantities used in the property determinations. The results are in reasonably good agreement with previously published data, which demonstrate the suitability of the proposed method, in particular, to the resistivity and total emissivity measurements. An interesting result is the existence of a minimum in the emissivity of the isotropic graphite at around 1120 K, consistent with the electrical resistivity results. PMID:22299976

  12. Results for the hybrid laminar flow control experiment conducted in the NASA Langley 8-foot transonic pressure tunnel on a 7-foot chord model

    NASA Technical Reports Server (NTRS)

    Bobbitt, Percy J.; Ferris, James C.; Harvey, William D.; Goradia, Suresh H.

    1992-01-01

    A description is given of the development of, and results from, the hybrid laminar flow control (HLFC) experiment conducted in the NASA LaRC 8 ft Transonic Pressure Tunnel on a 7 ft chord, 23 deg swept model. The methods/codes used to obtain the contours of the HLFC model surface and to define the suction requirements are outlined followed by a discussion of the model construction, suction system, instrumentation, and some example results from the wind tunnel tests. Included in the latter are the effects of Mach number, suction level, and the extent of suction. An assessment is also given of the effect of the wind tunnel environment on the suction requirements. The data show that, at or near the design Mach number, large extents of laminar flow can be achieved with suction mass flows over the first 25 percent, or less, of the chord. Top surface drag coefficients with suction extending from the near leading edge to 20 percent of the chord were approximately 40 percent lower than those obtained with no suction. The results indicate that HLFC can be designed for transonic speeds with lift and drag coefficients approaching those of LFC designs but with much smaller extents and levels of suction.

  13. Electrical Conductivity.

    ERIC Educational Resources Information Center

    Allen, Philip B.

    1979-01-01

    Examines Drude's classical (1900) theory of electrical conduction, details the objections to and successes of the 1900 theory, and investigates the Quantum (1928) theory of conduction, reviewing its successes and limitations. (BT)

  14. Detection of Salicylic Acid in Willow Bark: An Addition to a Classic Series of Experiments in the Introductory Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Clay, Matthew D.; McLeod, Eric J.

    2012-01-01

    Salicylic acid and its derivative, acetylsalicylic acid, are often encountered in introductory organic chemistry experiments, and mention is often made that salicylic acid was originally isolated from the bark of the willow tree. This biological connection, however, is typically not further pursued, leaving students with an impression that biology…

  15. Generation, Isolation, and Characterization of a Stable Enol from Grignard Addition to a Bis-Ester: A Microscale Experiment for the Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Nicaise, Olivier J. C.; Ostrom, Kyle F.; Dalke, Brent J.

    2005-01-01

    An experiment is described that introduces students to the concept of temperature-dependent stability of the tetrahedral intermediate in an acyl-transfer reaction. The process involves the determination of the structure of an alpha-ketoester and its corresponding remarkably stable enol ester to suggest a mechanism for the formation of the products.

  16. Qualitative impact of salinity, UV radiation and turbulence on leaching of organic plastic additives from four common plastics - A lab experiment.

    PubMed

    Suhrhoff, Tim Jesper; Scholz-Böttcher, Barbara M

    2016-01-15

    Four common consumer plastic samples (polyethylene, polystyrene, polyethylene terephthalate, polyvinylchloride) were studied to investigate the impact of physical parameters such as turbulence, salinity and UV irradiance on leaching behavior of selected plastic components. Polymers were exposed to two different salinities (i.e. 0 and 35 g/kg), UV radiation and turbulence. Additives (e.g. bisphenol A, phthalates, citrates, and Irgafos® 168 phosphate) and oligomers were detected in initial plastics and aqueous extracts. Identification and quantification was performed by GC-FID/MS. Bisphenol A and citrate based additives are leached easier compared to phthalates. The print highly contributed to the chemical burden of the analyzed polyethylene bag. The study underlines a positive relationship between turbulence and magnitude of leaching. Salinity had a minor impact that differs for each analyte. Global annual release of additives from assessed plastics into marine environments is estimated to be between 35 and 917 tons, of which most are derived from plasticized polyvinylchloride. PMID:26696590

  17. Research Experience and Agreement with Selected Ethics Principles from Canada's "Tri-Council Policy Statement--Ethical Conduct for Research Involving Humans"

    ERIC Educational Resources Information Center

    Fahy, Pat; Spencer, Bob

    2004-01-01

    An online survey was conducted of students, instructors, and researchers in distance education regarding principles for the ethical treatment of human research subjects. The study used an online questionnaire based on principles drawn from Canada's "Tri-Council Policy Statement, Ethical Conduct for Research Involving Humans" (TCPS, 2003), which…

  18. NATURAL GRADIENT EXPERIMENT ON SOLUTE TRANSPORT IN A SAND AQUIFER: SPATIAL VARIABILITY OF HYDRAULIC CONDUCTIVITY AND ITS ROLE IN THE DISPERSION PROCESS

    EPA Science Inventory

    The spatial variability of hydraulic conductivity at the site of a long-term tracer test performed in the Borden aquifer was examined in great detail by conducting permeability measurements on a series of cores taken along two cross sections. Along the two cross sections, a regul...

  19. Cooling of Gas Turbines I - Effects of Addition of Fins to Blade Tips and Rotor, Admission of Cooling Air Through Part of Nozzles, and Change in Thermal Conductivity of Turbine Components

    NASA Technical Reports Server (NTRS)

    Brown, Byron

    1947-01-01

    An analysis was developed for calculating the radial temperature distribution in a gas turbine with only the temperatures of the gas and the cooling air and the surface heat-transfer coefficient known. This analysis was applied to determine the temperatures of a complete wheel of a conventional single-stage impulse exhaust-gas turbine. The temperatures were first calculated for the case of the turbine operating at design conditions of speed, gas flow, etc. and with only the customary cooling arising from exposure of the outer blade flange and one face of the rotor to the air. Calculations were next made for the case of fins applied to the outer blade flange and the rotor. Finally the effects of using part of the nozzles (from 0 to 40 percent) for supplying cooling air and the effects of varying the metal thermal conductivity from 12 to 260 Btu per hour per foot per degree Farenheit on the wheel temperatures were determined. The gas temperatures at the nozzle box used in the calculations ranged from 1600F to 2000F. The results showed that if more than a few hundred degrees of cooling of turbine blades are required other means than indirect cooling with fins on the rotor and outer blade flange would be necessary. The amount of cooling indicated for the type of finning used could produce some improvement in efficiency and a large increase in durability of the wheel. The results also showed that if a large difference is to exist between the effective temperature of the exhaust gas and that of the blade material, as must be the case with present turbine materials and the high exhaust-gas temperatures desired (2000F and above), two alternatives are suggested: (a) If metal with a thermal conductivity comparable with copper is used, then the blade temperature can be reduced by strong cooling at both the blade tip and root. The center of the blade will be less than 2000F hotter than the ends; (b) With low conductivity materials some method of direct cooling other than

  20. Conduct disorder

    MedlinePlus

    Disruptive behavior - child; Impulse control problem - child ... Conduct disorder has been linked to: Child abuse Drug or alcohol abuse in the parents Family conflicts Genetic defects Poverty The diagnosis is more common among boys. It is ...

  1. Electrical Conductivity.

    ERIC Educational Resources Information Center

    Hershey, David R.; Sand, Susan

    1993-01-01

    Explains how electrical conductivity (EC) can be used to measure ion concentration in solutions. Describes instrumentation for the measurement, temperature dependence and EC, and the EC of common substances. (PR)

  2. Use of 13C and 15N mass spectrometry to study the decomposition of Calamagrostis epigeios in soil column experiments with and without ash additions.

    PubMed

    Ludwig, B; Heil, B; Flessa, H; Beese, F

    2000-01-01

    The dynamics of C and N in terrestrial ecosystems are not completely understood and the use of stable isotopes may be useful to gain further insight in the pathways of CO2 emissions and leaching of dissolved organic carbon (DOC) and nitrogen (DON) during decomposition of litter. Objectives were (i) to study the decomposition dynamics of Calamagrostis epigeios, a common grass species in forests, using 13C-depleted and 15N-enriched plants and (ii) to quantify the effect wood ash addition on the decomposition and leaching of DOC and DON. Decomposition was studied for 128 days under aerobic conditions at 8 degrees C and moisture close to field capacity in a spodic dystric Cambisol with mor-moder layer. Variants included control plots and additions of (i) Calamagrostis litter and (ii) Calamagrostis litter plus 4 kg ash m-2. (i) Decomposition of Calamagrostis resulted in a CO2 production of 76.2 g CO2-C m-2 (10% of added C) after 128 days and cumulative DOC production was 14.0 g C m-2 out of which 0.9 g C m-2 was Calamagrostis-derived (0.1% of added C). The specific CO2 formation and specific DOC production from Calamagrostis were 6 times higher (CO2) and 4 times smaller (DOC) than those from the organic layer. The amount of Calamagrostis-derived total N (NH4+, NO3-, DON) leached was 0.7 g N m-2 (4.8% of added N). Cumulative DON production was 0.8 g N m-2 which was slightly higher than for the control. During soil passage, much of the DOC and DON was removed due to sorption or decomposition. DOC and DON releases from the mineral soil (17 cm depth) were 6.3 g C m-2 and 0.5 g N m-2. (ii) Addition of ash resulted in a complete fixing of CO2 for 40 days due to carbonatisation. Afterwards, the CO2 production rates were similar to the variant without ash addition. Production of DOC (98.6 g C m-2) and DON (2.5 g N m-2) was marked, mainly owing to humus decay. However, Calamagrostis-derived DOC and Calamagrostis-derived total N were only 3.9 g C m-2 (0.5% of added C) and 0.5 g N

  3. Listening to Mothers II: Report of the Second National U.S. Survey of Women's Childbearing Experiences: Conducted January-February 2006 for Childbirth Connection by Harris Interactive(R) in partnership with Lamaze International.

    PubMed

    Declercq, Eugene R; Sakala, Carol; Corry, Maureen P; Applebaum, Sandra

    2007-01-01

    With permission from Childbirth Connection, the concise version of the Listening to Mothers II "Survey Methodology" is reprinted here. Harris Interactive(R) conducted Listening to Mothers II: Report of the Second National U.S. Survey of Women's Childbearing Experiences on behalf of Childbirth Connection. The survey consisted of 1,373 online interviews and 200 telephone interviews with women who had given birth in U.S. hospitals in 2005, with weighting of data to reflect the target population. Interviews were conducted from January 20 through February 21, 2006. The methods used to conduct the survey and analyze the data collected are described. PMID:18769522

  4. RF hyperthermia using conductive nanoparticles

    NASA Astrophysics Data System (ADS)

    Gach, H. Michael; Balachandrasekaran, Arvind; Nair, Tejas

    2010-02-01

    Specific absorption rate (SAR) heating using radiofrequency (RF) waves is affected by the RF frequency and amplitude, and the conductivity of the tissue. Recently, conductive nanoparticles were demonstrated to induce hyperthermia in vitro and in vivo upon irradiation with an external 13.56 MHz RF field. The addition of conductive nanoparticles was assumed to increase the tissue conductivity and SAR. However, no quantitative studies have been performed that characterize the conductivities of biocompatible colloids or tissues containing nanoparticles, and relate the conductivity to SAR. The complex permittivities were measured for colloids containing single-wall carbon nanotubes (SWCNTs) in normal saline with 0.32% w/v Pluronic F108 nonionic surfactant. The carbon concentrations of the colloids ranged from 0 to 88 mM. The permittivities were measured using a dielectric probe and RF network analyzer for RF frequencies from 200 MHz to 3 GHz. The nonionic surfactant was added to the colloids to minimize flocculation of the nanotubes during the RF heating experiments. The results were compared with prior measurements of colloids containing 0.02% Pluronic F108. The dielectric and conductivity of the 0.02% Pluronic colloids rose linearly with carbon concentration but the 0.32% Pluronic colloids varied from linearity. Based on the permittivity results, selected colloid samples were placed inside a Bruker 7T/20 magnetic resonance (MR) imaging (MRI) system and irradiated at 300 MHz using a high duty cycle RF pulse sequence. The temperature changes were measured directly using fiber-optic thermometers and indirectly using MR thermometry and spectroscopy. Temperature changes were consistent with the colloid conductivities.

  5. Seismic Absorption and Modulus Measurements in Porous Rocks in Lab and Field: Physical, Chemical, and Biological Effects of Fluids (Detecting a Biosurfactant Additive in a Field Irrigation Experiment)

    SciTech Connect

    Spetzler, Hartmut

    2006-05-01

    We have been exploring a new technology that is based on using low-frequency seismic attenuation data to monitor changes in fluid saturation conditions in two-fluid phase porous materials. The seismic attenuation mechanism is related to the loss of energy due to the hysteresis of resistance to meniscus movement (changes in surface tension, wettability) when a pore containing two fluids is stressed at very low frequencies (< 10 Hz). This technology has potential applications to monitoring changes in (1) leakage at buried waste sites, (2) contaminant remediation, and (3) flooding during enhanced petroleum recovery. We have concluded a three year field study at the Maricopa Agricultural Center site of the University of Arizona. Three sets of instruments were installed along an East-West line perpendicular to the 50m by 50m inigation site. Each set of instruments consisted of one three component seismometer and one tiltmeter. Microseisms and solid Earth-tides served as strain sources. The former have a power peak at a period of about 6 seconds and the tides have about two cycles per day. Installation of instruments commenced in late summer of 2002. The instruments operated nearly continuously until April 2005. During the fall of 2003 the site was irrigated with water and one year later with water containing 150 ppm of a biosurfactant additive. This biodegradable additive served to mimic a class of contaminants that change the surface tension of the inigation fluid. Tilt data clearly show tidal tilts superimposed on local tilts due to agricultural irrigation and field work. When the observed signals were correlated with site specific theoretical tilt signals we saw no anomalies for the water irrigation in 2003, but large anomalies on two stations for the surfactant irrigation in 2004. Occasional failures of seismometers as well as data acquisition systems contributed to less than continuous coverage. These data are noisier than the tilt data, but do also show possible

  6. Can additive measures add to an intersectional understanding? Experiences of gay and ethnic discrimination among HIV-positive Latino gay men

    PubMed Central

    Reisen, Carol A.; Brooks, Kelly D.; Zea, Maria Cecilia; Poppen, Paul J.; Bianchi, Fernanda T.

    2013-01-01

    The current study investigated a methodological question of whether traditional, additive, quantitative data can be used to address intersectional issues, and illustrated such an approach with a sample of 301 HIV-positive, Latino gay men in the U.S. Participants were surveyed using A-CASI. Hierarchical logistic set regression investigated the role of sets of variables reflecting demographic characteristics, gender nonconformity, and gay and ethnic discrimination in relation to depression and gay collective identity. Results showed the discrimination set was related to depression and to gay collective identity, as was gender nonconformity. Follow-up logistic regression showed that both types of discrimination were associated with greater depression, but gender nonconformity was not. Gay discrimination and gender nonconformity were positively associated with gay collective identity, whereas ethnic discrimination was negatively associated. Results are discussed in terms of the use of traditional quantitative data as a potential means of understanding intersectional issues, as well as of contributing to knowledge about individuals facing multiple structural inequalities. PMID:23647331

  7. Anaplastic Thyroid Cancer: The Addition of Systemic Chemotherapy to Radiotherapy Led to an Observed Improvement in Survival—A Single Centre Experience and Review of the Literature

    PubMed Central

    Lowe, Natalie M.; Loughran, Sean; Slevin, Nicholas J.; Yap, Beng K.

    2014-01-01

    Introduction. Anaplastic thyroid carcinoma (ATC) is rare yet accounts for up to 50% of all thyroid cancer deaths. This study reviews outcomes of patients with confirmed ATC referred to a tertiary oncology centre plus reviews the literature to explore how poor outcomes may be improved. Materials and Methods. The management and outcomes of 20 patients with ATC were reviewed. Results. Median age at diagnosis was 69.5 years. 19 patients died due to ATC, 40% of whom died from asphyxiation. Median survival for all cases was 59 days. Patients who had previous surgery prior to other treatment modalities had a longer median survival overall compared to those who had not had previous surgery (142 days compared to 59 days) and produced the one long-term survivor. Chemotherapy followed by radiotherapy (without previous surgery) was associated with longer median survival (220 days). Palliative radiotherapy alone did not decrease the rate of death by asphyxiation when compared to other single modality treatments. Conclusion. Multimodality treatment including surgery when feasible remains the best strategy to improve survival and prevent death from asphyxiation in the management of ATC. The addition of chemotherapy to our institutional protocol led to improved survival but prognosis remains very poor. PMID:25184150

  8. Conduction-limited crystallite melting

    NASA Astrophysics Data System (ADS)

    Lupulescu, A.; Glicksman, M. E.; Koss, M. B.

    2005-04-01

    High-purity pivalic acid (PVA) dendrites were observed growing under convection-free conditions during the isothermal dendritic growth experiment (IDGE) flown on NASA's space shuttle Columbia on STS-87. The IDGE was part of the complement of primary scientific experiments designated as the United States Microgravity Payload Mission (USMP4) launched late in 1997. The IDGE video data show that PVA dendrites may be melted without exhibiting any detectable relative motion with respect to the surrounding quiescent melt phase. Thus, melting occurs by heat conduction alone. When a small fixed superheating is imposed on pre-existing dendritic fragments, they melt steadily toward extinction. Individual fragments steadily decrease in size according to a square-root of time dependence predicted using quasi-static conduction-limited theory. Agreement between analytic melting theory and microgravity experiments was found originally if the melting process occurs under the restriction of shape-preserving conditions, where needle-like crystal fragments may be approximated as ellipsoids with a constant axial ratio. Among the new results reported here is the influence of capillarity effects on melting in needle-like crystallites, observed as a dramatic change in their axial ratio, when the size scale of a crystallite decreases below a critical value. In microgravity melting experiments, the axial ratio of individual crystallites does not remain constant, because of interactions with neighboring fragments within the mushy zone. The kinetic data were then "sectorized" to divide the total melting process into a series of short intervals. Each melting sector for a crystallite could then be approximated by a constant average value of the axial ratio. Sectorization also allows accurate prediction of melting kinetics by applying quasi-static heat conduction theory, despite the suspected presence of capillarity and the occurrence of fragmentation. These additional processes that accompany

  9. Appropriate Conduct

    ERIC Educational Resources Information Center

    Di Lullo, Louis

    2004-01-01

    Many years ago when the author assumed the role of assistant principal for school climate, discipline, and attendance, he inherited many school policies and guidelines that were outdated, unfair, and without merit in the current school climate. Because the school conduct code had not been revised since the school opened in 1960, many of the…

  10. Conducting Meetings.

    ERIC Educational Resources Information Center

    United Tribes Educational Technical Center, Bismarck, ND.

    Written for anyone interested in what makes a meeting run smoothly (and what doesn't), the guide for conducting meetings is divided into the following sections: the chairperson (his/her responsibilities, preparing an agenda, organizing discussions); the meeting (quorums, discussions, points of order, and clarification); the motion (making the…

  11. An ensemble Kalman filter approach to identify the hydraulic conductivity spatial distribution from electrical resistivity tomography time-lapse monitoring of three-dimensional tracer test experiments

    NASA Astrophysics Data System (ADS)

    Camporese, M.; Cassiani, G.; Deiana, R.; Perri, M. T.; Salandin, P.

    2012-04-01

    An approach based on the Lagrangian formulation of transport and the ensemble Kalman filter (EnKF) is applied to assess the spatial distribution of hydraulic conductivity K by assimilating time-lapse cross-hole electrical resistivity tomography (ERT) images generated for a synthetic tracer test in a heterogeneous aquifer. Assuming that the solute spreads as a passive tracer, for high Peclet numbers the spatial moments of the evolving plume are dominated by the spatial distribution of the hydraulic conductivity. The assimilation of the electrical conductivity 4D images allows updating both the hydrological state in terms of solute concentration and the spatial distribution of K. Thus, delineation of the tracer plume and estimation of the aquifer heterogeneity at the local scale can be achieved at the same time by means of this interpretation of time-lapse electrical images from tracer tests. We assess the impact on the performance of the hydrological inversion of the uncertainty inherently affecting ERT inversions in terms of tracer concentration and the choice of the prior statistics of K. The results show that realistic ERT images can be integrated into a hydrological model even within an uncoupled inverse modeling framework, the reconstruction of the hydraulic conductivity spatial distribution being satisfactory in the portion of the domain directly covered by the passage of the tracer. Aside from the issues commonly affecting inverse models, the proposed approach is subject to the problem of the filter inbreeding and the retrieval performance is sensitive to the choice of K prior geostatistical parameters.

  12. Electrodeless conductivity.

    PubMed

    Light, T S; McHale, E J; Fletcher, K S

    1989-01-01

    Electrodeless conductivity is a technique for measuring the concentration of electrolytes in solution and utilizes a probe consisting of two toroids in close proximity, both of which are immersed in the solution. In special cases, the toroids may be mounted externally on insulated pipes carrying the solution. One toroid radiates an alternating electric field in the audiofrequency range and the other acts as a receiver to pick up the small current induced by the ions moving in a conducting loop of solution. Coatings which would foul contacting electrodes, such as suspensions, precipitates or oil, have little or no effect. Applications are chiefly to continuous measurement in the chemical processing industries, including pulp and paper, mining and heavy chemical production. The principles and practical details of the method are reviewed and cell-diameter, wall, and temperature effects are discussed. PMID:18964695

  13. Heat conduction

    SciTech Connect

    Lilley, D.G.

    1987-01-01

    Analytical and numerical methods, including both finite difference and finite element techniques, are presented with applications to heat conduction problems. Numerical and analytical methods are integrated throughout the text and a variety of complexities are thoroughly treated with many problems, solutions and computer programs. This book is presented as a fundamental course suitable for senior undergraduate and first year graduate students, with end-of-chapter problems and answers included. Sample case studies and suggested projects are included.

  14. Conduction apraxia.

    PubMed

    Ochipa, C; Rothi, L J; Heilman, K M

    1994-10-01

    A left hemisphere damaged patient with ideomotor apraxia is described, whose performance on pantomime to verbal command was superior to pantomime imitation. His reception of these same gestures (gesture naming) was spared. This syndrome has been named conduction apraxia. To account for this selective impaired performance on gesture imitation, a separation of the representations for gesture production and reception is proposed and a non-lexical gesture processing route for gesture imitation is suggested. PMID:7931387

  15. THERMAL DISTRIBUTION SYSTEM EXPERIMENT

    SciTech Connect

    KRAJEWSKI,R.F.; ANDREWS,J.W.; WEI,G.

    1999-09-01

    A laboratory experiment has been conducted which tests for the effects of distribution system purging on system Delivery Effectiveness (DE) as defined in ASHRAE 152P. The experiment is described in its configuration, instrumentation, and data acquisition system. Data gathered in the experiment is given and discussed. The results show that purging of the distribution system alone does not offer any improvement of the system DE. Additional supporting tests were conducted regarding experimental simulations of buffer zones and bare pipe and are also discussed.

  16. Main results of the experiments conducted during the flight of the Kosmos-1129 Biosatellite and the status of preparation of studies on the next biosatllite

    NASA Technical Reports Server (NTRS)

    Ilin, E. A.

    1980-01-01

    Experiments included studies on the biological effects of weightlessness. Space flight stress, disorientation, and physiological factors are discussed for each experimental subject. The subjects included rats, drosophila flies, and plants. Metabolic rates were monitored along with other changes in the subject's activity cycles.

  17. Effects of Welfare and Employment Policies on Young Children: New Findings on Policy Experiments Conducted in the Early 1990s. Social Policy Report. Volume 19, Number 2

    ERIC Educational Resources Information Center

    Morris, Pamela A.; Gennetian, Lisa A.; Duncan, Greg J.

    2005-01-01

    Over the past 30 years, welfare and other public programs for poor families have focused increasingly on promoting parents' self-sufficiency by requiring and supporting employment. Evidence from a diverse set of random-assignment experiments now reveals some of the conditions under which promoting work among low-income, single parents helps or…

  18. The Utility of Using Mixed-Methods and Intersectionality Approaches in Conducting Research on Filipino American Students' Experiences with the Campus Climate and on Sense of Belonging

    ERIC Educational Resources Information Center

    Maramba, Dina C.; Museus, Samuel D.

    2011-01-01

    In this article, the authors discuss how merging mixed-methods and intersectional analyses can generate deeper and more authentic understandings of students' experiences within the campus climate and its relation to sense of belonging in college. They discuss overemphasis on one-dimensional analyses of campus climates and sense of belonging,…

  19. Conductivity Probe

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Thermal and Electrical Conductivity Probe (TECP) for NASA's Phoenix Mars Lander took measurements in Martian soil and in the air.

    The needles on the end of the instrument were inserted into the Martian soil, allowing TECP to measure the propagation of both thermal and electrical energy. TECP also measured the humidity in the surrounding air.

    The needles on the probe are 15 millimeters (0.6 inch) long.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  20. 20 CFR 655.46 - Additional employer-conducted recruitment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Attestations for Temporary Employment in Occupations Other Than Agriculture or Registered Nursing in the United... contact with State One-Stop Career Centers, and other print advertising, such as using a...

  1. 20 CFR 655.46 - Additional employer-conducted recruitment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Attestations for Temporary Employment in Occupations Other Than Agriculture or Registered Nursing in the United... contact with State One-Stop Career Centers, and other print advertising, such as using a...

  2. 20 CFR 655.46 - Additional employer-conducted recruitment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Attestations for Temporary Employment in Occupations Other Than Agriculture or Registered Nursing in the United... contact with State One-Stop Career Centers, and other print advertising, such as using a...

  3. [The experiments conducted by Japanese on human guinea pigs, and the use of biological weapons during the Sino-Japanese war (1937-1945)].

    PubMed

    Sabbatani, Sergio

    2014-09-01

    Starting from the end of the nineteenth century, and during the first four decades of the past century, Japan showed considerable military expansion, on the back of a pan-Asiatic and imperialistic ideology, comparable only to those expressed by Wilhelmian and Nazi Germany. This growth led to Japan playing an extremely important role in the Asia-Pacific continent, which unavoidably brought the country onto a collision course with the British Empire and the United States of America. The Japanese general Shiro Ishii, who had undoubted organisational abilities but also a propensity for crimes against mankind, starting from the end of the 1920s and during the subsequent decade, under the suggestion of a military physician, developed a research programme to obtain biological weapons, since he was aware of the lack of raw materials, technology and scientific background in nuclear weapons. This project was taken forward despite Japan's ratification of the Geneva protocol, undersigned by 70 nations, which posed strict limits to the use of both biological and chemical weapons. In actual fact, the protocol allowed these weapons for defensive purposes, and permitted their experimental development. The research programme, developed with the support of the high command of the Japanese army and certainly known by the Emperor (Tenno) Hirohito, had its operative basis from the year 1932 in the satellite state of Manchukuo, but later and paralleling the increased, aggressive behaviour towards China and the English and American colonies during World War II, spread towards other Asian provinces occupied by the Japanese armies, with other operative units. In these dedicated bases, which were true concentration camps, numerous experiments were carried out on human guinea pigs, frequently concluding with vivisection. Among others, experiments of freezing, thirst, hunger, loss of blood, wounding with firearms, and bone fractures, were performed, as well as the inoculation of

  4. Conducting a thermal conductivity survey

    NASA Technical Reports Server (NTRS)

    Allen, P. B.

    1985-01-01

    A physically transparent approximate theory of phonon decay rates is presented starting from a pair potential model of the interatomic forces in an insulator or semiconductor. The theory applies in the classical regime and relates the 3-phonon decay rate to the third derivative of the pair potential. Phonon dispersion relations do not need to be calculated, as sum rules relate all the needed quantities directly to the pair potential. The Brillouin zone averaged phonon lifetime turns out to involve a dimensionless measure of the anharmonicity multiplied by an effective density of states for 3-phonon decay. Results are given for rare gas and alkali halide crystals. For rare gases, the results are in good agreement with more elaborate perturbation calculations. Comparison to experimental data on phonon linewidths and thermal conductivity are made.

  5. Calibration of the RSS-131 high efficiency ionization chamber for radiation dose monitoring during plasma experiments conducted on plasma focus device

    NASA Astrophysics Data System (ADS)

    Szewczak, Kamil; Jednoróg, Sławomir

    2014-10-01

    Plasma research poses a radiation hazard. Due to the program of deuterium plasma research using the PF-1000 device, it is an intensive source of neutrons (up to 1011 n · pulse -1) with energy of 2,45 MeV and ionizing electromagnetic radiation with a broad energy spectrum. Both types of radiation are mostly emitted in ultra-short pulses (˜100 ns). The aim of this work was to test and calibrate the RSS-131 radiometer for its application in measurements of ultra-short electromagnetic radiation pulses with broad energy spectrum emitted during PF-1000 discharge. In addition, the results of raw measurements performed in the control room are presented.

  6. Thermal Conductivity of Rubble Piles

    NASA Astrophysics Data System (ADS)

    Luan, Jing; Goldreich, Peter

    2015-11-01

    Rubble piles are a common feature of solar system bodies. They are composed of monolithic elements of ice or rock bound by gravity. Voids occupy a significant fraction of the volume of a rubble pile. They can exist up to pressure P≈ {ε }Yμ , where {ε }Y is the monolithic material's yield strain and μ its rigidity. At low P, contacts between neighboring elements are confined to a small fraction of their surface areas. As a result, the effective thermal conductivity of a rubble pile, {k}{con}≈ k{(P/({ε }Yμ ))}1/2, can be orders of magnitude smaller than the thermal conductivity of its monolithic elements, k. In a fluid-free environment, only radiation can transfer energy across voids. It contributes an additional component, {k}{rad}=16{\\ell }σ {T}3/3, to the total effective conductivity, {k}{eff}={k}{con}+{k}{rad}. Here ℓ, the inverse of the opacity per unit volume, is of the order of the size of the elements, and voids. An important distinction between {k}{con} and {k}{rad} is that the former is independent of the size of the elements, whereas the latter is proportional to it. Our expression for {k}{eff} provides a good fit to the depth dependence of thermal conductivity in the top 140 cm of the lunar regolith. It also offers a good starting point for detailed modeling of thermal inertias for asteroids and satellites. Measurement of the response of surface temperature to variable insolation is a valuable diagnostic of a regolith. There is an opportunity for careful experiments under controlled laboratory conditions to test models of thermal conductivity such as the one we outline.

  7. 1-week habitation of two people in an airtight facility, CEEF with two goats and 23 crops, conducted with 89% self-sufficiency in food and without O2-addition and CO2-release - analysis of exchange of carbon and oxygen among organisms and water circulation in the CEEF -

    NASA Astrophysics Data System (ADS)

    Tako, Y.; Tsuga, S.; Tani, T.; Arai, R.; Komatsubara, O.; Shinohara, M.

    Three 1-week experiments were conducted from September to October of 2005 in which two human subjects named as eco-nauts were enclosed and worked in an airtight facility called Closed Ecosystem Experiment Facilities CEEF The test involved connecting a Plant Module PM with 23 crops including rice soybean peanut and sugar beet to an Animal Habitation Module AHM which included the eco-nauts and two Shiba-goats Although only 34 weight of the food consumed by the eco-nauts was produced by crops in the PM in the first experiment it was 81 in the second and third experiments As for feed to the goats 40 rice straw was produced in the PM in the first experiment and all of the feed rice straw soybean leaf and peanut shell was produced in the PM in the second and third experiments In all these experiments the crops produced more oxygen than the amount consumed by respiration of human and animals The oxygen build-up in the atmosphere of the PM from crop photosynthesis was separated and supplied to atmosphere of the AHM Carbon dioxide build-up in atmosphere of the AHM from respiration of eco-nauts and Shiba-goats was separated and supplied back to atmosphere of the PM Carbon in waste except for a part of that in human feces was withdrawn and not recycled for these experiments Therefore carbon dioxide from respiration compensated the demand for photosynthesis of the crops Amounts of carbon in edible and inedible parts of harvested crop biomass and amount of carbon taken by the eco-nauts and Shiba-goats were also estimated Water transpired through

  8. Rapid prototype extruded conductive pathways

    DOEpatents

    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.

  9. Thermal conductivity of metals

    NASA Technical Reports Server (NTRS)

    Kazem, Sayyed M.

    1990-01-01

    The objective is to familiarize students with steady and unsteady heat transfer by conduction and with the effect of thermal conductivity upon temperature distribution through a homogeneous substance. The elementary heat conduction experiment presented is designed for associate degree technology students in a simple manner to enhance their intuition and to clarify many confusing concepts such as temperature, thermal energy, thermal conductivity, heat, transient and steady flows. The equipment set is safe, small, portable (10 kg) and relatively cheap (about $1200): the electric hot plate 2 kg (4.4 lb) for $175: the 24 channel selector and Thermocouple Digital Readout (Trendicator) 4.5 kg (10 lb) for about $1000; the three metal specimens (each of 2.5 cm diameter and 11 cm length), base plate and the bucket all about 3 kg (7 lb) for about $25. The experiment may take from 60 to 70 minutes. Although the hot plate surface temperature could be set from 90 to 370 C (maximum of 750 watts) it is a good practice to work with temperatures of 180 to 200 C (about 400 watts). They may experiment in squads of 2, 3 or even 4, or the instructor may demonstrate it for the whole class.

  10. Attitudes toward and experiences of gender issues among physician teachers: A survey study conducted at a university teaching hospital in Sweden

    PubMed Central

    Risberg, Gunilla; Johansson, Eva E; Westman, Göran; Hamberg, Katarina

    2008-01-01

    Background Gender issues are important to address during medical education, however research about the implementation of gender in medical curricula reports that there are obstacles. The aim of this study was to explore physician teachers' attitudes to gender issues. Methods As part of a questionnaire, physician teachers at Umeå University in Sweden were given open-ended questions about explanations for and asked to write examples why they found gender important or not. The 1 469 comments from the 243 respondents (78 women, 165 men) were analyzed by way of content analysis. The proportion of comments made by men and women in each category was compared. Results We found three themes in our analysis: Understandings of gender, problems connected with gender and approaches to gender. Gender was associated with differences between women and men regarding behaviour and disease, as well as with inequality of life conditions. Problems connected with gender included: delicate situations involving investigations of intimate body parts or sexual attraction, different expectations on male and female physicians and students, and difficulty fully understanding the experience of people of the opposite sex. The three approaches to gender that appeared in the comments were: 1) avoidance, implying that the importance of gender in professional relationships was recognized but minimized by comparing gender with aspects, such as personality and neutrality; 2) simplification, implying that gender related problems were easy to address, or already solved; and 3) awareness, implying that the respondent was interested in gender issues or had some insights in research about gender. Only a few individuals described gender as an area of competence and knowledge. There were comments from men and women in all categories, but there were differences in the relative weight for some categories. For example, recognizing gender inequities was more pronounced in the comments from women and avoidance

  11. Mid-crust fluid and water-rock interaction kinetic experiments and their geophysical significance: 3. in situ measurements of electric conductance of the water-rock interaction system at high temperatures

    NASA Astrophysics Data System (ADS)

    Hu, S.; Zhang, R.; Zhang, X.

    2013-12-01

    Recently, we designed a new experimental apparatus, which was used to measure dissolution rates as water-rock interactions, and simultaneously in situ measure the electric conductance of the multi phase (rock - fluid) system. At first, a tubular reactor is put in horizontally. The rock sample was crushed and sieved to 20-40 mesh, and cleaned, then put in a titanium network bag inside of the vessel. The electric conductivity detectors were connected to the two ends of the vessel. Fluid inlet and outlet were also fabricated in the two ends of the vessel. And the furnace, temperature controller, liquid pump, back pressure regulator etc. are involved in the whole experimental system. High temperature (T) and pressure (P) electric conductivity measuring system consists of an electric conductivity detector (ECD limit.), which was reformed by us and connected to the vessel; and a transfer: T23-CDH-UM: 5.67(L)×3.50(W)×5.67(H) (inch).The distance between the two electrode of the sensor is 10cm. The electrode is 5cm of length and its diameter is 5/16 inch. Water-rock interaction experiments were performed using this apparatus. The volume inside of vessel is 10.81 ml, l= 170mm, d=4.5mm and 7.246g rock sample put in the vessel. The fluid velocity was changed from 1.5 to 3.5 ml/min, allowing the water through the sample. As in situ to measure the electric conductance of the rock-fluids in the vessel, continuously record the electric conductance, each record in 5 seconds. Water-basalt interaction experiments were carried out and in situ measured electric conductance at high T up to 450°C and at 22 to 36MPa. Basalt sample was collected from natural outcrop (volcanic area in Yangtze valley, China, which is K-rich trachy-basalt. Rock sample was crushed and sieved to 20-40 mesh, and cleaned. 8.0097g sample was put in the vessel (surface area: 1.37m2/g ). Experiments found dissolution rates (dis.r.) for different metals of the rock vary with T. Usually, dis.r., rSi increase with T

  12. 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.

  13. NASA technology flight experiments program

    NASA Technical Reports Server (NTRS)

    Pruscha, Stephen L.; Levine, Jack; Russo, Samuel C.

    1995-01-01

    In addition to its scientific and life sciences experimental programs, NASA conducts flight experiments directed at development of space systems technologies. The experiments are conducted to obtain research data, to evaluate the performance or operation of experimental hardware in the space environment, or to validate components, subsystems, or systems prior to application in future spacecraft or missions. The requirements for specific technology experiments, and the priority assigned to them, vary significantly depending on the maturity of the technology. Some of the flight experiments address technologies still in the early research stage, while others are conducted to validate technology at relatively advanced levels of maturity. This paper discusses the overall technology flight experiments program and reports in some detail on four current or recently flown experiments ranging from research to technology validation at the system prototype level.

  14. Color Addition and Subtraction Apps

    ERIC Educational Resources Information Center

    Ruiz, Frances; Ruiz, Michael J.

    2015-01-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step…

  15. The Training and Field Work Experiences of Community Health Workers conducting non-invasive, population-based screening for Cardiovascular Disease in Four Communities in Low and Middle-Income Settings

    PubMed Central

    Denman, Catalina A.; Montano, Carlos Mendoza; Gaziano, Thomas A.; Levitt, Naomi; Rivera-Andrade, Alvaro; Carrasco, Diana Munguía; Zulu, Jabu; Khanam, Masuma Akter; Puoane, Thandi

    2015-01-01

    Background Cardiovascular disease (CVD) is on the rise in low- and middle-income countries (LMIC) and is proving difficult to combat due to the emphasis on improving outcomes in maternal and child health and infectious diseases, against a backdrop of severe human resource and infrastructure constraints. Effective task-sharing from physicians or nurses to community health workers (CHWs) to conduct population-based screening for persons at risk, has the potential to mitigate the impact of CVD on vulnerable populations. CHWs in Bangladesh, Guatemala, Mexico, and South Africa were trained to conduct non-invasive population-based screening for persons at high risk for CVD. Objective (s) The objectives of this study were to quantitatively assess the performance of CHWs during training and to qualitatively capture their training and fieldwork experiences while conducting non-invasive screening for cardiovascular disease (CVD) risk in their communities. Methods Written tests were used to assess CHWs’ acquisition of content knowledge during training, and focus group discussions conducted to capture their training and fieldwork experiences. Results Training was effective at increasing the CHWs’ content knowledge of cardiovascular disease (CVD) and this knowledge was largely retained up to six months after the completion of field work. Common themes which need to be addressed when designing task sharing with CHWs in chronic diseases are identified, including language, respect, and compensation. The importance of having intimate knowledge of the community receiving services from design to implementation is underscored. Conclusions Effective training for screening for CVD in community settings should have a strong didactic core that is supplemented with culture-specific adaptations in the delivery of instruction. The incorporation of expert and intimate knowledge of the communities themselves is critical, from the design to implementation phases of training. Challenges such

  16. 15 CFR 270.200 - Technical conduct of investigation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... collapse. (vi) Conduct small and full-scale experiments to provide additional data and verify the computer... building(s) using computer models to identify the most probable technical cause (or causes) of the failure and the uncertainty(ies) associated with it (them). Such models may include initial damage,...

  17. 15 CFR 270.200 - Technical conduct of investigation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... collapse. (vi) Conduct small and full-scale experiments to provide additional data and verify the computer... building(s) using computer models to identify the most probable technical cause (or causes) of the failure and the uncertainty(ies) associated with it (them). Such models may include initial damage,...

  18. Benefits of additives application during combustion of phytomass

    NASA Astrophysics Data System (ADS)

    Palacka, Matej; Vician, Peter; Holubčík, Michal; Jandačka, Jozef

    2016-06-01

    Phytomass, particularly wheat straw as a source of energy has countless benefits, but it has many problems in its direct burn too. The worst problem is the ash flow temperature. The aim of study was to analyze and reduce the problems of the wheat straw combustion. The experiment was conducted under realistic conditions. In this paper was implemented analysis of ash features with and without adding additives into the wheat straw. Selected samples were laboratory processed and examined. The result of the work was the impact of additional additives for ash features.

  19. Effective thermal conductivity of damaged composites

    NASA Astrophysics Data System (ADS)

    Graham, Samuel, Jr.

    Ceramic matrix composites (CMCs) are susceptible to matrix cracking, fiber-matrix debonding, and oxidation processes as result of their application environments. These damage mechanisms act to degrade thermal conductivity and is a concern for many CMC applications. Prediction of this degradation relies on an accurate understanding of damage and thermal conductivity, and the development of analytical or numerical models. An experimental investigation into the degradation of thermal conductivity of CMCs was performed. In addition, an assessment was made of current micromechanics models for predicting thermal conductivity degradation. Experiments were performed on unidirectional reinforced Nicalon-LAS II glass-ceramic composites. Thermal conductivity was determined through flash diffusivity experiments. This procedure was also modified to treat orthotropic composite materials. Samples were subjected to mechanical loading-, oxidation-, and thermal shock-induced damage. The results showed that mechanical loading-induced damage resulted in no change in thermal conductivity transverse to the fiber axis and up to a 3.5% change parallel to the fibers. Mechanical loading followed by oxidation resulted in thermal conductivity degradation up to 26% and 10% transverse and parallel to the fibers, respectively. These data show the importance of the fiber-matrix interface in controlling both the longitudinal and transverse thermal conductivities of damaged composites. Predictions of thermal conductivity degradation parallel to the fiber direction were made with a shear-lag type micromechanics model. Results were in excellent agreement with experimental data. Thermal diffusivity data from isothermal oxidation and thermal shock experiments showed that this procedure is an effective nondestructive monitoring method. An assessment of transverse thermal conductivity rnicromechanics models was made through comparison with numerical solutions for random fiber inclusions with random

  20. Effects of chemical additives on microbial enhanced oil recovery processes

    SciTech Connect

    Bryant, R.S.; Chase, K.L.; Bertus, K.M.; Stepp, A.K.

    1989-12-01

    An extensive laboratory study has been conducted to determine (1) the role of the microbial cells and products in oil displacement, (2) the relative rates of transport of microbial cells and chemical products from the metabolism of nutrient in porous media, and (3) the effects of chemical additives on the oil recovery efficiency of microbial formulations. This report describes experiments relating to the effects of additives on oil recovery efficiency of microbial formulations. The effects of additives on the oil recovery efficiency of microbial formulations were determined by conducting oil displacement experiments in 1-foot-long Berea sandstone cores. Sodium tripolyphosphate (STPP), a low-molecular-weight polyacrylamide polymer, a lignosulfonate surfactant, and sodium bicarbonate were added to a microbial formulation at a concentration of 1%. The effects of using these additives in a preflush prior to injection of the microbial formulation were also evaluated. Oil-displacement experiments with and without a sodium bicarbonate preflush were conducted in 4-foot-long Berea sandstone cores, and samples of in situ fluids were collected at various times at four intermediate points along the core. The concentrations of metabolic products and microbes in the fluid samples were determined. 9 refs., 22 figs., 8 tabs.

  1. Is it efficient to co-compost and co-vermicompost green waste with biochar and/or clay to reduce CO2 emissions? A short-term laboratory experiment on (vermi)composts with additives.

    NASA Astrophysics Data System (ADS)

    Barthod, Justine; Rumpel, Cornélia; Paradelo, Remigio; Dignac, Marie-France

    2016-04-01

    Intensive farming practices can lead to a depletion of soil organic matter, negatively impacting important soil properties such as structural stability, fertility and C storage. The addition of organic amendments such as compost and vermicompost, rich in carbon, helps maintaining soil organic matter levels or restoring degraded soils. Composting and vermicomposting are based on stabilization of organic matter through the mineralization of easily decomposable organic matter compounds, therefore releasing greenhouse gases, including CO2. The aim of this study was to evaluate the global potential reduction of such emissions by the use of additives (2:1 clay and/or biochar): during (vermi)composting processes and after use of the final products as soil amendments. We hypothesized that the interactions between the additives and organic matter may lead to carbon stabilization and that such interactions may be enhanced by the presence of worms (Eisenia). We added in different proportions clay (25% or 50%), biochar (10%) and a mixture of biochar (10%) with clay (25%) to pre-composted green waste. The CO2 emissions of the composting and vermicomposting processes were measured during 21 days. After that, the amendments were added to a loamy cambisol soil and the CO2 emissions were monitored during 30 days of a laboratory experiment. The most efficient treatments in terms of reducing global CO2 emissions were the co-vermicomposting process with 25% clay followed by co-composting with 50% clay and with 10% biochar plus 25% clay. In this treatment (vermicompost with 25% clay), the carbon emissions were decreased by up to 44% compared to regular compost. Addition of biochar reduced CO2 emissions only during composting. Co-composting with biochar could be a promising avenue to limit global CO2 emissions whereas in presence of worms clay additions are better suited. These findings suggest that the presence of worms increased the formation of organo-mineral associations and thus C

  2. A Sensitivity Analysis of a Thin Film Conductivity Estimation Method

    SciTech Connect

    McMasters, Robert L; Dinwiddie, Ralph Barton

    2010-01-01

    An analysis method was developed for determining the thermal conductivity of a thin film on a substrate of known thermal properties using the flash diffusivity method. In order to determine the thermal conductivity of the film using this method, the volumetric heat capacity of the film must be known, as determined in a separate experiment. Additionally, the thermal properties of the substrate must be known, including conductivity and volumetric heat capacity. The ideal conditions for the experiment are a low conductivity film adhered to a higher conductivity substrate. As the film becomes thinner with respect to the substrate or, as the conductivity of the film approaches that of the substrate, the estimation of thermal conductivity of the film becomes more difficult. The present research examines the effect of inaccuracies in the known parameters on the estimation of the parameter of interest, the thermal conductivity of the film. As such, perturbations are introduced into the other parameters in the experiment, which are assumed to be known, to find the effect on the estimated thermal conductivity of the film. A baseline case is established with the following parameters: Substrate thermal conductivity 1.0 W/m-K Substrate volumetric heat capacity 106 J/m3-K Substrate thickness 0.8 mm Film thickness 0.2 mm Film volumetric heat capacity 106 J/m3-K Film thermal conductivity 0.01 W/m-K Convection coefficient 20 W/m2-K Magnitude of heat absorbed during the flash 1000 J/m2 Each of these parameters, with the exception of film thermal conductivity, the parameter of interest, is varied from its baseline value, in succession, and placed into a synthetic experimental data file. Each of these data files is individually analyzed by the program to determine the effect on the estimated film conductivity, thus quantifying the vulnerability of the method to measurement errors.

  3. Neutron Characterization for Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Watkins, Thomas; Bilheux, Hassina; An, Ke; Payzant, Andrew; DeHoff, Ryan; Duty, Chad; Peter, William; Blue, Craig; Brice, Craig A.

    2013-01-01

    Oak Ridge National Laboratory (ORNL) is leveraging decades of experience in neutron characterization of advanced materials together with resources such as the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR) shown in Fig. 1 to solve challenging problems in additive manufacturing (AM). Additive manufacturing, or three-dimensional (3-D) printing, is a rapidly maturing technology wherein components are built by selectively adding feedstock material at locations specified by a computer model. The majority of these technologies use thermally driven phase change mechanisms to convert the feedstock into functioning material. As the molten material cools and solidifies, the component is subjected to significant thermal gradients, generating significant internal stresses throughout the part (Fig. 2). As layers are added, inherent residual stresses cause warping and distortions that lead to geometrical differences between the final part and the original computer generated design. This effect also limits geometries that can be fabricated using AM, such as thin-walled, high-aspect- ratio, and overhanging structures. Distortion may be minimized by intelligent toolpath planning or strategic placement of support structures, but these approaches are not well understood and often "Edisonian" in nature. Residual stresses can also impact component performance during operation. For example, in a thermally cycled environment such as a high-pressure turbine engine, residual stresses can cause components to distort unpredictably. Different thermal treatments on as-fabricated AM components have been used to minimize residual stress, but components still retain a nonhomogeneous stress state and/or demonstrate a relaxation-derived geometric distortion. Industry, federal laboratory, and university collaboration is needed to address these challenges and enable the U.S. to compete in the global market. Work is currently being conducted on AM technologies at the ORNL

  4. Heat conduction in conducting polyaniline nanofibers

    NASA Astrophysics Data System (ADS)

    Nath, Chandrani; Kumar, A.; Syu, K.-Z.; Kuo, Y.-K.

    2013-09-01

    Thermal conductivity and specific heat of conducting polyaniline nanofibers are measured to identify the nature of heat carrying modes combined with their inhomogeneous structure. The low temperature thermal conductivity results reveal crystalline nature while the high temperature data confirm the amorphous nature of the material suggesting heterogeneous model for conducting polyaniline. Extended acoustic phonons dominate the low temperature (<100 K) heat conduction, while localized optical phonons hopping, assisted by the extended acoustic modes, account for the high temperature (>100 K) heat conduction.

  5. Electrical Conductivity in Textiles

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Copper is the most widely used electrical conductor. Like most metals, though, it has several drawbacks: it is heavy, expensive, and can break. Fibers that conduct electricity could be the solutions to these problems, and they are of great interest to NASA. Conductive fibers provide lightweight alternatives to heavy copper wiring in a variety of settings, including aerospace, where weight is always a chief concern. This is an area where NASA is always seeking improved materials. The fibers are also more cost-effective than metals. Expenditure is another area where NASA is always looking to make improvements. In the case of electronics that are confined to small spaces and subject to severe stress, copper is prone to breaking and losing connection over time. Flexible conductive fibers eliminate that problem. They are more supple and stronger than brittle copper and, thus, find good use in these and similar situations. While clearly a much-needed material, electrically conductive fibers are not readily available. The cost of new technology development, with all the pitfalls of troubleshooting production and the years of testing, and without the guarantee of an immediate market, is often too much of a financial hazard for companies to risk. NASA, however, saw the need for electrical fibers in its many projects and sought out a high-tech textile company that was already experimenting in this field, Syscom Technology, Inc., of Columbus, Ohio. Syscom was founded in 1993 to provide computer software engineering services and basic materials research in the areas of high-performance polymer fibers and films. In 1999, Syscom decided to focus its business and technical efforts on development of high-strength, high-performance, and electrically conductive polymer fibers. The company developed AmberStrand, an electrically conductive, low-weight, strong-yet-flexible hybrid metal-polymer YARN.

  6. Plant uptake and downward migration of 85Sr and 137Cs after their deposition on to flooded rice fields: lysimeter experiments with and without the addition of KCl and lime.

    PubMed

    Choi, Y H; Lim, K M; Choi, H J; Choi, G S; Lee, H S; Lee, C W

    2005-01-01

    In order to study the plant uptake and downward migration of radiostrontium and radiocesium deposited on to a flooded rice field, 85Sr and 137Cs were applied to the standing water over an acidic sandy soil in planted lysimeters. The plant uptake was quantified with the areal transfer factor (TFa, m2 kg(-1)-dry plant). Following the spiking 14 days after transplanting, the TFa values for the hulled seeds were 3.9 x 10(-4) for 85Sr and 1.4 x 10(-4) for 137Cs, whereas those for the straws were 1.3 x 10(-2) and 3.2 x 10(-4), respectively. The 137Cs TFa from the spiking at the anthesis/milky-ripe stage was several times higher than that from the earlier spiking, whereas the difference was much less in the 85Sr TFa. Such an increase in the 137Cs TFa was attributed mainly to an enhanced plant-base uptake. The addition of KCl and lime after the spiking significantly reduced the TFa values of both radionuclides. The reducing effect was greater for the later spiking. An appreciable fraction of the applied activity leached out of the lysimeter for 85Sr, whereas a negligible fraction leached for 137Cs. The leaching was remarkably increased by the KCl and lime addition for both. A conspicuous localization of 137Cs with respect to the soil surface was observed. In a batch experiment, the 137Cs concentration in the standing water decreased more rapidly than that of 85Sr, both of which were fitted to the power functions of the elapsed time. To add KCl and lime slowed such decreases to lessen the distribution coefficients (Kd) of both 85Sr and 137Cs. PMID:15465178

  7. Electric utility use of fireside additives. Final report

    SciTech Connect

    Locklin, D.W.; Krause, H.H.; Anson, D.; Reid, W.

    1980-01-01

    Fireside additives have been used or proposed for use in fossil-fired utility boilers to combat a number of problems related to boiler performance and reliability. These problems include corrosion, fouling, superheat control, and acidic emissions. Fuel additives and other fireside additives have been used mainly with oil firing; however, there is growing experience with additives in coal-firing, especially for flyash conditioning to improve the performance of electrostatic precipitators. In decisions regarding the selection and use of additives, utilities have had to rely extensively on empiricism, due partly to an incomplete understanding of processes involved and partly to the limited amount of quantitative data. The study reported here was sponsored by the Electric Power Research Institute to assemble and analyze pertinent operating experience and to recommend guidelines for utility decisions on the use of additives. The combined results of the state-of-the-art review of technical literature and a special survey of utility experience are reported. A total of 38 utilities participated in the survey, providing information on trials conducted on 104 units in 93 different plants. Altogether, 445 separate trials were reported, each representing a unit/additive/fuel combination. Additives used in these trials included 90 different additive formulations, both pure compounds and proprietary products. These formulations were categorized into 37 generic classes according to their chemical constituents, and the results of the survey are presented by these generic classes. The findings are organized according to the operating problems for which fireside additives are used. Guidelines are presented for utility use in additive selection and in planning additive trials.

  8. Lithium ion conducting electrolytes

    DOEpatents

    Angell, C. Austen; Liu, Changle

    1996-01-01

    A liquid, predominantly lithium-conducting, ionic electrolyte having exceptionally high conductivity at temperatures of 100.degree. C. or lower, including room temperature, and comprising the lithium salts selected from the group consisting of the thiocyanate, iodide, bromide, chloride, perchlorate, acetate, tetrafluoroborate, perfluoromethane sulfonate, perfluoromethane sulfonamide, tetrahaloaluminate, and heptahaloaluminate salts of lithium, with or without a magnesium-salt selected from the group consisting of the perchlorate and acetate salts of magnesium. Certain of the latter embodiments may also contain molecular additives from the group of acetonitrile (CH.sub.3 CN) succinnonitrile (CH.sub.2 CN).sub.2, and tetraglyme (CH.sub.3 --O--CH.sub.2 --CH.sub.2 --O--).sub.2 (or like solvents) solvated to a Mg.sup.+2 cation to lower the freezing point of the electrolyte below room temperature. Other particularly useful embodiments contain up to about 40, but preferably not more than about 25, mol percent of a long chain polyether polymer dissolved in the lithium salts to provide an elastic or rubbery solid electrolyte of high ambient temperature conductivity and exceptional 100.degree. C. conductivity. Another embodiment contains up to about but not more than 10 mol percent of a molecular solvent such as acetone.

  9. Lithium ion conducting electrolytes

    DOEpatents

    Angell, C.A.; Liu, C.

    1996-04-09

    A liquid, predominantly lithium-conducting, ionic electrolyte is described having exceptionally high conductivity at temperatures of 100 C or lower, including room temperature, and comprising the lithium salts selected from the group consisting of the thiocyanate, iodide, bromide, chloride, perchlorate, acetate, tetrafluoroborate, perfluoromethane sulfonate, perfluoromethane sulfonamide, tetrahaloaluminate, and heptahaloaluminate salts of lithium, with or without a magnesium-salt selected from the group consisting of the perchlorate and acetate salts of magnesium. Certain of the latter embodiments may also contain molecular additives from the group of acetonitrile (CH{sub 3}CN), succinnonitrile (CH{sub 2}CN){sub 2}, and tetraglyme (CH{sub 3}--O--CH{sub 2}--CH{sub 2}--O--){sub 2} (or like solvents) solvated to a Mg{sup +2} cation to lower the freezing point of the electrolyte below room temperature. Other particularly useful embodiments contain up to about 40, but preferably not more than about 25, mol percent of a long chain polyether polymer dissolved in the lithium salts to provide an elastic or rubbery solid electrolyte of high ambient temperature conductivity and exceptional 100 C conductivity. Another embodiment contains up to about but not more than 10 mol percent of a molecular solvent such as acetone. 2 figs.

  10. Conducting the Heat

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Heat conduction plays an important role in the efficiency and life span of electronic components. To keep electronic components running efficiently and at a proper temperature, thermal management systems transfer heat generated from the components to thermal surfaces such as heat sinks, heat pipes, radiators, or heat spreaders. Thermal surfaces absorb the heat from the electrical components and dissipate it into the environment, preventing overheating. To ensure the best contact between electrical components and thermal surfaces, thermal interface materials are applied. In addition to having high conductivity, ideal thermal interface materials should be compliant to conform to the components, increasing the surface contact. While many different types of interface materials exist for varying purposes, Energy Science Laboratories, Inc. (ESLI), of San Diego, California, proposed using carbon velvets as thermal interface materials for general aerospace and electronics applications. NASA s Johnson Space Center granted ESLI a Small Business Innovation Research (SBIR) contract to develop thermal interface materials that are lightweight and compliant, and demonstrate high thermal conductance even for nonflat surfaces. Through Phase II SBIR work, ESLI created Vel-Therm for the commercial market. Vel-Therm is a soft, carbon fiber velvet consisting of numerous high thermal conductivity carbon fibers anchored in a thin layer of adhesive. The velvets are fabricated by precision cutting continuous carbon fiber tows and electrostatically flocking the fibers into uncured adhesive, using proprietary techniques.

  11. Evaluation of the DHCE Experiment

    SciTech Connect

    Greenwood, Lawrence R.; Baldwin, David L.; Hollenberg, Glenn W.; Kurtz, Richard J.

    2002-03-31

    The Dynamic Helium Charging Experiment (DHCE) experiment was conducted in the Fast Flux Test Facility (FFTF) during cycle 12, which was completed in 1992. The purpose of the experiment was to enhance helium generation in vanadium alloys to simulate fusion reactor helium-to-dpa ratios with a target goal of 4-5 appm He/dpa. The Fusion Materials Science Program is considering mounting another experiment in hopes of gathering additional data on the effect of helium on the mechanical and physical properties of vanadium structural materials. Pacific Northwest National Laboratory was assigned the task of evaluating the feasibility of conducting another DHCE experiment by carefully evaluating the results obtained of the first DHCE experiment. This report summarizes the results of our evaluation and presents recommendations for consideration by the Materials Science Coordinators Organization.

  12. Estimating Mesophyll Conductance in the Tropical Rainforest

    NASA Astrophysics Data System (ADS)

    Coughlin, I.

    2015-12-01

    In the current research modeling the carbon cycle, some of the biggest setbacks are methodological barriers to calculating the gross primary production (GPP) in the terrestrial biosphere. However, recent developments in high precision gas measurements now allow the use of COS as a potential tracer for determination of GPP, independently of CO2 .Since the tropics are implicated as being the source of the most significant reduction of carbon uptake by the majority of models, making accurate GPP measurements in the tropics is particularly important for carbon modeling. In order to constrain measurements of GPP in the tropics, carbonyl sulfide fluxes on a leaf chamber scale and a canopy-wide scale will be analyzed in a field site in the central Amazon. Accompanying this experiment, I am measuring the resistance of CO2 passing through the intercellular airspaces in the leaf to the sites of carboxylation, known as mesophyll conductance. Mesophyll conductance is poorly documented in the tropics, and remains a centrally limiting factor in plant uptake of COS and CO2 - with upward estimates of 40% of the CO2 diffusional limitation of photosynthesis hinging on mesophyll conductance (Warren, 2008). This makes mesophyll conductance comparable in magnitude to that of the stomatal conductance, suggesting that mesophyll conductance is one of the most fundamental measurements necessary for developing the predictive capacity of plants' response to ecosystem changes. Accurate measurements of the mesophyll conductance also lead to better informed models that can upscale assimilation measurements from leaf chambers, by providing quantitative constraints for modeling the uptake of carbonyl sulfide and carbon dioxide by the leaf. Additionally, since mesophyll conductance reacts to environmental variation, it can be used as an indicator for leaf stress. Measurements are taken using the 'variable J' technique, involving the use of combined fluorescence measurements and gas exchange data

  13. Psychology Experiments.

    ERIC Educational Resources Information Center

    McGraw, Ken; Tew, Mark D.; Williams, John E.

    2001-01-01

    A goal of the PsychExperiments project was to reduce the financial burden on psychology departments for hardware/software used in their laboratories. In its third year, the PsychExperiments site now hosts 39 experiments. Over 200 classrooms worldwide have signed up as official site users and there have been nearly 10,000 data sessions conducted.…

  14. Measurement of heat conduction through stacked screens

    NASA Technical Reports Server (NTRS)

    Lewis, M. A.; Kuriyama, T.; Kuriyama, F.; Radebaugh, R.

    1998-01-01

    This paper describes the experimental apparatus for the measurement of heat conduction through stacked screens as well as some experimental results taken with the apparatus. Screens are stacked in a fiberglass-epoxy cylinder, which is 24.4 mm in diameter and 55 mm in length. The cold end of the stacked screens is cooled by a Gifford-McMahon (GM) cryocooler at cryogenic temperature, and the hot end is maintained at room temperature. Heat conduction through the screens is determined from the temperature gradient in a calibrated heat flow sensor mounted between the cold end of the stacked screens and the GM cryocooler. The samples used for these experiments consisted of 400-mesh stainless steel screens, 400-mesh phosphor bronze screens, and two different porosities of 325-mesh stainless steel screens. The wire diameter of the 400-mesh stainless steel and phosphor bronze screens was 25.4 micrometers and the 325-mesh stainless steel screen wire diameters were 22.9 micrometers and 27.9 micrometers. Standard porosity values were used for the experimental data with additional porosity values used on selected experiments. The experimental results showed that the helium gas between each screen enhanced the heat conduction through the stacked screens by several orders of magnitude compared to that in vacuum. The conduction degradation factor is the ratio of actual heat conduction to the heat conduction where the regenerator material is assumed to be a solid rod of the same cross sectional area as the metal fraction of the screen. This factor was about 0.1 for the stainless steel and 0.022 for the phosphor bronze, and almost constant for the temperature range of 40 to 80 K at the cold end.

  15. Color Addition and Subtraction Apps

    NASA Astrophysics Data System (ADS)

    Ruiz, Frances; Ruiz, Michael J.

    2015-10-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step in understanding mathematical representations of RGB color. Finally, color addition and subtraction are presented for the X11 colors from web design to illustrate yet another real-life application of color mixing.

  16. Some guidelines for conducting a health fair.

    PubMed Central

    Richie, N D

    1976-01-01

    Health professionals are being asked with increasing frequency to participate in, or to conduct, health fairs. There is, however, a lack of published practical advice available to persons undertaking such an event for the first time. Based upon my experience in this area, participants are advised to (a) clearly define in advance the objectives to be achieved by this activity, (b) give careful attention to the timing, location, and financing of the event, (c) encourage the active participation in the event of both professionals and lay persons in the community, (d) pay particular attention to publicizing the event, since the fair's success will be directly related to visitor attendance, and (e) evaluate the event to determine whether the sponsors' objective were met, whether additional health fairs should be conducted, and what changes should be made when similar events are held in the future. PMID:818665

  17. Molecular electronics: A DNA that conducts

    NASA Astrophysics Data System (ADS)

    Scheer, Elke

    2014-12-01

    Experiments with conducting atomic force microscopy provide a clear demonstration of long-range charge transport in G-quadruplex DNA molecules, and allow a hopping transport model to be developed that could also be applied to other conductive polymers.

  18. Electric utility use of fireside additives. Final report

    SciTech Connect

    Locklin, D.W.; Krause, H.H.; Anson, D.; Reid, W.

    1980-01-01

    Fireside additives have been used or proposed for use in fossil-fired utility boilers to combat a number of problems related to boiler performance and reliability. These problems include corrosion, fouling, superheat control, and acidic emissions. Fuel additivies and other fireside additives have been used mainly with oil firing; however, there is growing experience with additives in coal-firing, especially for flyash conditioning to improve the performance of electrostatic precipitators. In decisions regarding the selection and use of additives, utilities have had to rely extensively on empiricism, due partly to our incomplete understanding of processes involved and partly to the limited amount of quantitative data. The study reported here was sponsored by the Electric Power Research Institute to assemble and analyze pertinent operating experience and to recommend guidelines for utility decisions on the use of additives. This report describes the combined results of the state-of-the-art review of technical literature and a special survey of utility experience. A total of 38 utilities participated in the survey, providing information on trials conducted on 104 units in 93 different plants. Altogether, 445 separate trials were reported, each representing a unit/additive/fuel combination. 90 different additive formulations, both pure compounds and proprietary products, were categorized into 37 generic classes according to their chemical constituents, and the results of the survey are presented by these generic classes. This report is organized according to the operating problems for which fireside additives are used. Guidelines are presented for utility use in additive selection and in planning additive trials.

  19. 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

  20. [Food additives and healthiness].

    PubMed

    Heinonen, Marina

    2014-01-01

    Additives are used for improving food structure or preventing its spoilage, for example. Many substances used as additives are also naturally present in food. The safety of additives is evaluated according to commonly agreed principles. If high concentrations of an additive cause adverse health effects for humans, a limit of acceptable daily intake (ADI) is set for it. An additive is a risk only when ADI is exceeded. The healthiness of food is measured on the basis of nutrient density and scientifically proven effects. PMID:24772784

  1. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. R.; St. Clair, T. L.; Burks, H. D.; Stoakley, D. M.

    1987-01-01

    A method has been found for enhancing the melt flow of thermoplastic polyimides during processing. A high molecular weight 422 copoly(amic acid) or copolyimide was fused with approximately 0.05 to 5 pct by weight of a low molecular weight amic acid or imide additive, and this melt was studied by capillary rheometry. Excellent flow and improved composite properties on graphite resulted from the addition of a PMDA-aniline additive to LARC-TPI. Solution viscosity studies imply that amic acid additives temporarily lower molecular weight and, hence, enlarge the processing window. Thus, compositions containing the additive have a lower melt viscosity for a longer time than those unmodified.

  2. Conductance fluctuations in nanostructures

    NASA Astrophysics Data System (ADS)

    Zhu, Ningjia

    1997-12-01

    -statistics of the scattering states satisfies the same universality class as those of the bound states. This provides a practical means of measuring the chaotic scattering from transport experiments. Finally, I studied a ballistic system without any impurities: a window-coupled quantum wire. This system has the ability of switching electric current from one wire to the other quantum mechanically. I have made a systematic study of the complicated magneto-conductance fluctuations observed in this system experimentally. My theoretical results are in qualitative agreement with the measurements, and they provide the much needed understanding of the physics controlling these oscillations.

  3. Hydrogen sulfide production by sulfate-reducing bacteria utilizing additives eluted from plastic resins.

    PubMed

    Tsuchida, Daisuke; Kajihara, Yusuke; Shimidzu, Nobuhiro; Hamamura, Kengo; Nagase, Makoto

    2011-06-01

    In the present study it was demonstrated that organic additives eluted from plastic resins could be utilized as substrates by sulfate-reducing bacteria. Two laboratory-scale experiments, a microcosm experiment and a leaching experiment, were conducted using polyvinyl chloride (PVC) as a model plastic resin. In the former experiment, the conversion of sulfate to sulfide was evident in microcosms that received plasticized PVC as the sole carbon source, but not in those that received PVC homopolymer. Additionally, dissolved organic carbon accumulated only in microcosms that received plasticized PVC, indicating that the dissolved organic carbon originated from additives. In the leaching experiment, phenol and bisphenol A were found in the leached solutions. These results suggest that the disposal of waste plastics in inert waste landfills may result in the production of H(2)S. PMID:21135024

  4. Materials science experiments in space

    NASA Technical Reports Server (NTRS)

    Gelles, S. H.; Giessen, B. C.; Glicksman, M. E.; Margrave, J. L.; Markovitz, H.; Nowick, A. S.; Verhoeven, J. D.; Witt, A. F.

    1978-01-01

    The criteria for the selection of the experimental areas and individual experiments were that the experiment or area must make a meaningful contribution to the field of material science and that the space environment was either an absolute requirement for the successful execution of the experiment or that the experiment can be more economically or more conveniently performed in space. A number of experimental areas and individual experiments were recommended for further consideration as space experiments. Areas not considered to be fruitful and others needing additional analysis in order to determine their suitability for conduct in space are also listed. Recommendations were made concerning the manner in which these materials science experiments are carried out and the related studies that should be pursued.

  5. Additive usage levels.

    PubMed

    Langlais, R

    1996-01-01

    With the adoption of the European Parliament and Council Directives on sweeteners, colours and miscellaneous additives the Commission is now embarking on the project of coordinating the activities of the European Union Member States in the collection of the data that are to make up the report on food additive intake requested by the European Parliament. This presentation looks at the inventory of available sources on additive use levels and concludes that for the time being national legislation is still the best source of information considering that the directives have yet to be transposed into national legislation. Furthermore, this presentation covers the correlation of the food categories as found in the additives directives with those used by national consumption surveys and finds that in a number of instances this correlation still leaves a lot to be desired. The intake of additives via food ingestion and the intake of substances which are chemically identical to additives but which occur naturally in fruits and vegetables is found in a number of cases to be higher than the intake of additives added during the manufacture of foodstuffs. While the difficulties are recognized in contributing to the compilation of food additive intake data, industry as a whole, i.e. the food manufacturing and food additive manufacturing industries, are confident that in a concerted effort, use data on food additives by industry can be made available. Lastly, the paper points out that with the transportation of the additives directives into national legislation and the time by which the food industry will be able to make use of the new food legislative environment several years will still go by; food additives use data by the food industry will thus have to be reviewed at the beginning of the next century. PMID:8792135

  6. An additional middle cuneiform?

    PubMed Central

    Brookes-Fazakerley, S.D.; Jackson, G.E.; Platt, S.R.

    2015-01-01

    Additional cuneiform bones of the foot have been described in reference to the medial bipartite cuneiform or as small accessory ossicles. An additional middle cuneiform has not been previously documented. We present the case of a patient with an additional ossicle that has the appearance and location of an additional middle cuneiform. Recognizing such an anatomical anomaly is essential for ruling out second metatarsal base or middle cuneiform fractures and for the preoperative planning of arthrodesis or open reduction and internal fixation procedures in this anatomical location. PMID:26224890

  7. Radiative thermal conduction fronts

    NASA Technical Reports Server (NTRS)

    Borkowski, Kazimierz J.; Balbus, Steven A.; Fristrom, Carl C.

    1990-01-01

    The discovery of the O VI interstellar absorption lines in our Galaxy by the Copernicus observatory was a turning point in our understanding of the Interstellar Medium (ISM). It implied the presence of widespread hot (approx. 10 to the 6th power K) gas in disk galaxies. The detection of highly ionized species in quasi-stellar objects' absorption spectra may be the first indirect observation of this hot phase in external disk galaxies. Previous efforts to understand extensive O VI absorption line data from our Galaxy were not very successful in locating the regions where this absorption originates. The location at interfaces between evaporating ISM clouds and hot gas was favored, but recent studies of steady-state conduction fronts in spherical clouds by Ballet, Arnaud, and Rothenflug (1986) and Bohringer and Hartquist (1987) rejected evaporative fronts as the absorption sites. Researchers report here on time-dependent nonequilibrium calculations of planar conductive fronts whose properties match well with observations, and suggest reasons for the difference between the researchers' results and the above. They included magnetic fields in additional models, not reported here, and the conclusions are not affected by their presence.

  8. Radiative thermal conduction fronts

    NASA Astrophysics Data System (ADS)

    Borkowski, Kazimierz J.; Balbus, Steven A.; Fristrom, Carl C.

    1990-07-01

    The discovery of the O VI interstellar absorption lines in our Galaxy by the Copernicus observatory was a turning point in our understanding of the Interstellar Medium (ISM). It implied the presence of widespread hot (approx. 10 to the 6th power K) gas in disk galaxies. The detection of highly ionized species in quasi-stellar objects' absorption spectra may be the first indirect observation of this hot phase in external disk galaxies. Previous efforts to understand extensive O VI absorption line data from our Galaxy were not very successful in locating the regions where this absorption originates. The location at interfaces between evaporating ISM clouds and hot gas was favored, but recent studies of steady-state conduction fronts in spherical clouds by Ballet, Arnaud, and Rothenflug (1986) and Bohringer and Hartquist (1987) rejected evaporative fronts as the absorption sites. Researchers report here on time-dependent nonequilibrium calculations of planar conductive fronts whose properties match well with observations, and suggest reasons for the difference between the researchers' results and the above. They included magnetic fields in additional models, not reported here, and the conclusions are not affected by their presence.

  9. EFFECT OF LIGHT INTENSITY, SOIL TYPE, AND LITHIUM ADDITION ON SPINACH AND MUSTARD GREENS LEAF CONSTITUENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A greenhouse experiment was conducted near Weslaco, Texas (Lat. 26o 8' N, Long. 97o 57' W) between 14 Dec. 2005 and 17 Feb 2006 to evaluate the effect of soil type, light environment, and lithium addition on the leaf nutrients of spinach and mustard greens. Cultivars Samish (Spinacia oleracea) and...

  10. Carbamate deposit control additives

    SciTech Connect

    Honnen, L.R.; Lewis, R.A.

    1980-11-25

    Deposit control additives for internal combustion engines are provided which maintain cleanliness of intake systems without contributing to combustion chamber deposits. The additives are poly(oxyalkylene) carbamates comprising a hydrocarbyloxyterminated poly(Oxyalkylene) chain of 2-5 carbon oxyalkylene units bonded through an oxycarbonyl group to a nitrogen atom of ethylenediamine.

  11. High thermal conductivity of diamond

    NASA Technical Reports Server (NTRS)

    Stephan, Patrick M.

    1993-01-01

    The objectives of this educational exercise were to demonstrate the high rate of heat flow from a synthetic diamond coupon and to compare it to a commonly used thermal conductor, such as copper. The principles of heat transfer by conduction and convection may also be demonstrated. A list of equipment and supplies and the procedure for the experiment are presented.

  12. 11 CFR 9008.13 - Additional audits.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Convention Committees § 9008.13 Additional audits. In accordance with 11 CFR 104.16(c), the Commission, pursuant to 11 CFR 111.10, may upon affirmative vote of four members conduct an audit and...

  13. 11 CFR 9007.4 - Additional audits.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... FINANCING EXAMINATIONS AND AUDITS; REPAYMENTS § 9007.4 Additional audits. In accordance with 11 CFR 104.16(c), the Commission, pursuant to 11 CFR 111.10, may upon affirmative vote of four members conduct an...

  14. 11 CFR 9007.4 - Additional audits.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... EXAMINATIONS AND AUDITS; REPAYMENTS § 9007.4 Additional audits. In accordance with 11 CFR 104.16(c), the Commission, pursuant to 11 CFR 111.10, may upon affirmative vote of four members conduct an audit and...

  15. 11 CFR 9007.4 - Additional audits.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... FINANCING EXAMINATIONS AND AUDITS; REPAYMENTS § 9007.4 Additional audits. In accordance with 11 CFR 104.16(c), the Commission, pursuant to 11 CFR 111.10, may upon affirmative vote of four members conduct an...

  16. 11 CFR 9008.13 - Additional audits.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Convention Committees § 9008.13 Additional audits. In accordance with 11 CFR 104.16(c), the Commission, pursuant to 11 CFR 111.10, may upon affirmative vote of four members conduct an audit and...

  17. 11 CFR 9008.13 - Additional audits.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Convention Committees § 9008.13 Additional audits. In accordance with 11 CFR 104.16(c), the Commission, pursuant to 11 CFR 111.10, may upon affirmative vote of four members conduct an audit and...

  18. Nitrogen oxide abatement by distributed fuel addition

    SciTech Connect

    Wendt, J.O.L.; Meraab, J.

    1988-06-27

    This research is directed towards the development of engineering guidelines that define the application of distributed fuel addition as a technique for NOx abatement. It is expected that multiple fuel and air addition in the post-flame of a combustion process will increase free radical concentrations which destroy nitrogenous species and thus help them decay toward their equilibrium concentrations, which can be very low in that region of the combustor. Screening experiments were conducted on a laboratory scale downfired combustor. The objective was to compare NOx emissions arising from various combustion configurations, including fuel and/or air staging. Although the primary focus of this research is on NO control, a secondary effort was directed towards the measurement of N2O emissions from various coal combustion processes. N2O has been identified as a trace gas responsible for stratospheric ozone depletion, and has been hypothesized to arise from combustion processes, in amounts roughly proportional to NO emissions. Results presented in this report showed that the ratio N2O/NO was far from constant. The introduction of secondary air into a combustion process was accompanied an increase in N2O emissions. The measured N2O was always less than 10 ppm even under the most favorable combustion conditions. Reburning with premixed fuel and air mixtures was not effective in reducing NO emissions.

  19. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Fletcher, James C. (Inventor); Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1992-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  20. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1993-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of the additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  1. Smog control fuel additives

    SciTech Connect

    Lundby, W.

    1993-06-29

    A method is described of controlling, reducing or eliminating, ozone and related smog resulting from photochemical reactions between ozone and automotive or industrial gases comprising the addition of iodine or compounds of iodine to hydrocarbon-base fuels prior to or during combustion in an amount of about 1 part iodine per 240 to 10,000,000 parts fuel, by weight, to be accomplished by: (a) the addition of these inhibitors during or after the refining or manufacturing process of liquid fuels; (b) the production of these inhibitors for addition into fuel tanks, such as automotive or industrial tanks; or (c) the addition of these inhibitors into combustion chambers of equipment utilizing solid fuels for the purpose of reducing ozone.

  2. Food Additives and Hyperkinesis

    ERIC Educational Resources Information Center

    Wender, Ester H.

    1977-01-01

    The hypothesis that food additives are causally associated with hyperkinesis and learning disabilities in children is reviewed, and available data are summarized. Available from: American Medical Association 535 North Dearborn Street Chicago, Illinois 60610. (JG)

  3. Additional Types of Neuropathy

    MedlinePlus

    ... A A Listen En Español Additional Types of Neuropathy Charcot's Joint Charcot's Joint, also called neuropathic arthropathy, ... can stop bone destruction and aid healing. Cranial Neuropathy Cranial neuropathy affects the 12 pairs of nerves ...

  4. 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.

  5. 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.

  6. Effectiveness of various organometallics as antiwear additives in mineral oil

    NASA Technical Reports Server (NTRS)

    Buckley, D. H.

    1977-01-01

    Sliding friction experiments were conducted with 1045 steel contacting 302 stainless steel and lubricated with various organometallics in mineral oil. Auger emission spectroscopy was used to determine the element present in the wear contact zone. The results indicate that there are organometallics which are as effective an antiwear additives as the commonly used zinc dialkyl dithiophosphate. These include dimethyl cadmium, triphenyl lead thiomethoxide, and triphenyl tin chloride. The additives were examined in concentrations to 1 weight percent. With dimethyl cadmium at concentrations of 0.5 weight percent and above, cadmium was detected in the contact zone. Coincident with the detection of cadmium, a marked decrease in the friction coefficient was observed. All additives examined reduced friction, but only the aforementioned reduced wear to a level comparable to that observed with zinc dialkyl dithiophosphate.

  7. Protein conducting nanopores

    NASA Astrophysics Data System (ADS)

    Harsman, Anke; Krüger, Vivien; Bartsch, Philipp; Honigmann, Alf; Schmidt, Oliver; Rao, Sanjana; Meisinger, Christof; Wagner, Richard

    2010-11-01

    About 50% of the cellular proteins have to be transported into or across cellular membranes. This transport is an essential step in the protein biosynthesis. In eukaryotic cells secretory proteins are transported into the endoplasmic reticulum before they are transported in vesicles to the plasma membrane. Almost all proteins of the endosymbiotic organelles chloroplasts and mitochondria are synthesized on cytosolic ribosomes and posttranslationally imported. Genetic, biochemical and biophysical approaches led to rather detailed knowledge on the composition of the translocon-complexes which catalyze the membrane transport of the preproteins. Comprehensive concepts on the targeting and membrane transport of polypeptides emerged, however little detail on the molecular nature and mechanisms of the protein translocation channels comprising nanopores has been achieved. In this paper we will highlight recent developments of the diverse protein translocation systems and focus particularly on the common biophysical properties and functions of the protein conducting nanopores. We also provide a first analysis of the interaction between the genuine protein conducting nanopore Tom40SC as well as a mutant Tom40SC (\\mathrm {S}_{54} \\to E ) containing an additional negative charge at the channel vestibule and one of its native substrates, CoxIV, a mitochondrial targeting peptide. The polypeptide induced a voltage-dependent increase in the frequency of channel closure of Tom40SC corresponding to a voltage-dependent association rate, which was even more pronounced for the Tom40SC S54E mutant. The corresponding dwelltime reflecting association/transport of the peptide could be determined with \\bar {t}_{\\mathrm {off}} \\cong 1.1 ms for the wildtype, whereas the mutant Tom40SC S54E displayed a biphasic dwelltime distribution (\\bar {t}_{\\mathrm {off}}^1 \\cong 0.4 ms \\bar {t}_{\\mathrm {off}}^2 \\cong 4.6 ms).

  8. Magneto-inductive conductivity sensor

    NASA Astrophysics Data System (ADS)

    Floume, Timmy

    2011-12-01

    Multi-element inductive coil systems are used to measure locally resolved conductivity profile. Usually such sensors rely on the separate interrogation of each coil. In addition, the coils must generally be magnetically decoupled for accurate signal processing. Here we demonstrate a metamaterial conductivity sensor that uses broadband interrogation of a line of coupled resonators. No decoupling is needed, which allows a transmission measurement to be carried out. The resonant elements of the metamaterial are coupled with each other and their neighbourhood which affects their quality factor. We derive analytically an algorithm to extract the local perturbation in each element from the modal measurement. We investigate numerically the performance of the sensor and derive an optimal configuration in terms of nearest neighbour coupling and the initial non-uniformity. Finally we implement a four-element magneto inductive conductivity sensor and show that a conductive perturbation along the line can be accurately reconstructed. Generalisation to higher number of elements is also discussed.

  9. Recommended Protocol for Round Robin Studies in Additive Manufacturing

    PubMed Central

    Moylan, Shawn; Brown, Christopher U.; Slotwinski, John

    2016-01-01

    One way to improve confidence and encourage proliferation of additive manufacturing (AM) technologies and parts is by generating more high quality data describing the performance of AM processes and parts. Many in the AM community see round robin studies as a way to generate large data sets while distributing the cost among the participants, thereby reducing the cost to individual users. The National Institute of Standards and Technology (NIST) has conducted and participated in several of these AM round robin studies. While the results of these studies are interesting and informative, many of the lessons learned in conducting these studies concern the logistics and methods of the study and unique issues presented by AM. Existing standards for conducting interlaboratory studies of measurement methods, along with NIST’s experience, form the basis for recommended protocols for conducting AM round robin studies. The role of round robin studies in AM qualification, some of the limitations of round robin studies, and the potential benefit of less formal collaborative experiments where multiple factors, AM machine being only one, are varied simultaneously are also discussed. PMID:27274602

  10. Additive Manufacturing Infrared Inspection

    NASA Technical Reports Server (NTRS)

    Gaddy, Darrell

    2014-01-01

    Additive manufacturing is a rapid prototyping technology that allows parts to be built in a series of thin layers from plastic, ceramics, and metallics. Metallic additive manufacturing is an emerging form of rapid prototyping that allows complex structures to be built using various metallic powders. Significant time and cost savings have also been observed using the metallic additive manufacturing compared with traditional techniques. Development of the metallic additive manufacturing technology has advanced significantly over the last decade, although many of the techniques to inspect parts made from these processes have not advanced significantly or have limitations. Several external geometry inspection techniques exist such as Coordinate Measurement Machines (CMM), Laser Scanners, Structured Light Scanning Systems, or even traditional calipers and gages. All of the aforementioned techniques are limited to external geometry and contours or must use a contact probe to inspect limited internal dimensions. This presentation will document the development of a process for real-time dimensional inspection technique and digital quality record of the additive manufacturing process using Infrared camera imaging and processing techniques.

  11. Phenylethynyl Containing Reactive Additives

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

    2002-01-01

    Phenylethynyl containing reactive additives were prepared from aromatic diamine, containing phenylethvnvl groups and various ratios of phthalic anhydride and 4-phenylethynviphthalic anhydride in glacial acetic acid to form the imide in one step or in N-methyl-2-pvrrolidinone to form the amide acid intermediate. The reactive additives were mixed in various amounts (10% to 90%) with oligomers containing either terminal or pendent phenylethynyl groups (or both) to reduce the melt viscosity and thereby enhance processability. Upon thermal cure, the additives react and become chemically incorporated into the matrix and effect an increase in crosslink density relative to that of the host resin. This resultant increase in crosslink density has advantageous consequences on the cured resin properties such as higher glass transition temperature and higher modulus as compared to that of the host resin.

  12. 10 CFR 2.625 - Additional considerations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... License Under 10 Cfr Part 52 § 2.625 Additional considerations. (a) The Commission will not conduct more... 10 Energy 1 2012-01-01 2012-01-01 false Additional considerations. 2.625 Section 2.625 Energy NUCLEAR REGULATORY COMMISSION RULES OF PRACTICE FOR DOMESTIC LICENSING PROCEEDINGS AND ISSUANCE OF...

  13. 10 CFR 2.625 - Additional considerations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Work Authorizations Early Partial Decisions on Site Suitability-Combined License Under 10 Cfr Part 52 § 2.625 Additional considerations. (a) The Commission will not conduct more than one review of site... 10 Energy 1 2014-01-01 2014-01-01 false Additional considerations. 2.625 Section 2.625...

  14. 10 CFR 2.625 - Additional considerations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... License Under 10 Cfr Part 52 § 2.625 Additional considerations. (a) The Commission will not conduct more... 10 Energy 1 2011-01-01 2011-01-01 false Additional considerations. 2.625 Section 2.625 Energy NUCLEAR REGULATORY COMMISSION RULES OF PRACTICE FOR DOMESTIC LICENSING PROCEEDINGS AND ISSUANCE OF...

  15. 10 CFR 2.625 - Additional considerations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Work Authorizations Early Partial Decisions on Site Suitability-Combined License Under 10 Cfr Part 52 § 2.625 Additional considerations. (a) The Commission will not conduct more than one review of site... 10 Energy 1 2013-01-01 2013-01-01 false Additional considerations. 2.625 Section 2.625...

  16. Edge conduction in vacuum glazing

    SciTech Connect

    Simko, T.M.; Collins, R.E.; Beck, F.A.; Arasteh, D.

    1995-03-01

    Vacuum glazing is a form of low-conductance double glazing using in internal vacuum between the two glass sheets to eliminate heat transport by gas conduction and convection. An array of small support pillars separates the sheets; fused solder glass forms the edge seal. Heat transfer through the glazing occurs by radiation across the vacuum gap, conduction through the support pillars, and conduction through the bonded edge seal. Edge conduction is problematic because it affects stresses in the edge region, leading to possible failure of the glazing; in addition, excessive heat transfer because of thermal bridging in the edge region can lower overall window thermal performance and decrease resistance to condensation. Infrared thermography was used to analyze the thermal performance of prototype vacuum glazings, and, for comparison, atmospheric pressure superwindows. Research focused on mitigating the edge effects of vacuum glazings through the use of insulating trim, recessed edges, and framing materials. Experimentally validated finite-element and finite-difference modeling tools were used for thermal analysis of prototype vacuum glazing units and complete windows. Experimental measurements of edge conduction using infrared imaging were found to be in good agreement with finite-element modeling results for a given set of conditions. Finite-element modeling validates an analytic model developed for edge conduction.

  17. Additives in plastics.

    PubMed Central

    Deanin, R D

    1975-01-01

    The polymers used in plastics are generally harmless. However, they are rarely used in pure form. In almost all commercial plastics, they are "compounded" with monomeric ingredients to improve their processing and end-use performance. In order of total volume used, these monomeric additives may be classified as follows: reinforcing fibers, fillers, and coupling agents; plasticizers; colorants; stabilizers (halogen stabilizers, antioxidants, ultraviolet absorbers, and biological preservatives); processing aids (lubricants, others, and flow controls); flame retardants, peroxides; and antistats. Some information is already available, and much more is needed, on potential toxicity and safe handling of these additives during processing and manufacture of plastics products. PMID:1175566

  18. Japanese Experiment Module (JEM)

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Japanese Experiment Module (JEM) pressure module is removed from its shipping crate and moved across the floor of the Space Station Processing Facility at Kennedy Space Center (KSC) to a work stand. A research laboratory, the pressurized module is the first element of the JEM, named 'Kibo' (Hope) to arrive at KSC. Japan's primary contribution to the International Space Station, the module will enhance unique research capabilities of the orbiting complex by providing an additional environment in which astronauts will conduct experiments. The JEM also includes an exposed facility or platform for space environment experiments, a robotic manipulator system, and two logistics modules. The various JEM components will be assembled in space over the course of three Shuttle missions.

  19. Calibration-free electrical conductivity measurements for highly conductive slags

    SciTech Connect

    MACDONALD,CHRISTOPHER J.; GAO,HUANG; PAL,UDAY B.; VAN DEN AVYLE,JAMES A.; MELGAARD,DAVID K.

    2000-05-01

    This research involves the measurement of the electrical conductivity (K) for the ESR (electroslag remelting) slag (60 wt.% CaF{sub 2} - 20 wt.% CaO - 20 wt.% Al{sub 2}O{sub 3}) used in the decontamination of radioactive stainless steel. The electrical conductivity is measured with an improved high-accuracy-height-differential technique that requires no calibration. This method consists of making continuous AC impedance measurements over several successive depth increments of the coaxial cylindrical electrodes in the ESR slag. The electrical conductivity is then calculated from the slope of the plot of inverse impedance versus the depth of the electrodes in the slag. The improvements on the existing technique include an increased electrochemical cell geometry and the capability of measuring high precision depth increments and the associated impedances. These improvements allow this technique to be used for measuring the electrical conductivity of highly conductive slags such as the ESR slag. The volatilization rate and the volatile species of the ESR slag measured through thermogravimetric (TG) and mass spectroscopy analysis, respectively, reveal that the ESR slag composition essentially remains the same throughout the electrical conductivity experiments.

  20. Biobased lubricant additives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fully biobased lubricants are those formulated using all biobased ingredients, i.e. biobased base oils and biobased additives. Such formulations provide the maximum environmental, safety, and economic benefits expected from a biobased product. Currently, there are a number of biobased base oils that...

  1. Multifunctional fuel additives

    SciTech Connect

    Baillargeon, D.J.; Cardis, A.B.; Heck, D.B.

    1991-03-26

    This paper discusses a composition comprising a major amount of a liquid hydrocarbyl fuel and a minor low-temperature flow properties improving amount of an additive product of the reaction of a suitable diol and product of a benzophenone tetracarboxylic dianhydride and a long-chain hydrocarbyl aminoalcohol.

  2. Quantum Conductance in Metal Nanowires

    NASA Astrophysics Data System (ADS)

    Ugarte, Daniel

    2004-03-01

    Quantum Conductance in Metal Nanowires D. Ugarte Brazilian National Synchrotron Light Laboratory C.P. 6192, 13084-971 Campinas SP, Brazil. Electrical transport properties of metallic nanowires (NWs) have received great attention due to their quantum conductance behavior. Atomic scale wires can be generated by stretching metal contacts; during the elongation and just before rupture, the NW conductance shows flat plateaus and abrupt jumps of approximately a conductance quantum. In this experiments, both the NW atomic arrangement and conductance change simultaneously, making difficult to discriminate electronic and structural effects. In this work, the atomic structure of NWs was studied by time-resolved in situ experiments in a high resolution transmission electron microscope, while their electrical properties using an UHV mechanically controllable break junction (MCBJ). From the analysis of numerous HRTEM images and videos, we have deduced that metal (Au, Ag, Pt, etc.) junctions generated by tensile deformation are crystalline and free of defects. The neck structure is strongly dependent on the surface properties of the analyzed metal, this was verified by comparing different metal NWs (Au, Ag, Cu), which have similar atomic structure (FCC), but show very different faceting patterns. The correlation between the observed structural and transport properties of NW points out that the quantum conductance behavior is defined by preferred atomic arrangement at the narrowest constriction. In the case of magnetic (ex. Fe,Co,Ni) or quasi-magnetic (ex. Pd) wires, we have observed that one-atom-thick structures show a conductance of half the quantum as expected for a fully spin polarized current. This phenomenon seems to occur spontaneously for magnetic suspended atom-chains in zero magnetic field and at room temperature. These results open new opportunities for spin control in nanostructures. Funded by FAPESP, LNLS and CNPq.

  3. Nerve conduction velocity

    MedlinePlus

    Nerve conduction velocity (NCV) is a test to see how fast electrical signals move through a nerve. ... normal body temperature. Being too cold slows nerve conduction. Tell your doctor if you have a cardiac ...

  4. Nerve conduction velocity

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003927.htm Nerve conduction velocity To use the sharing features on this page, please enable JavaScript. Nerve conduction velocity (NCV) is a test to see how ...

  5. The Conductivity of Solutions.

    ERIC Educational Resources Information Center

    Rayner-Canham, Geoff

    1993-01-01

    Presents historical background and modern explanations for the popular demonstration of showing conductivity of solutions through the insertion of a light-bulb conductivity tester into deionized water and water with salt in it. (PR)

  6. Electrically conductive and thermally conductive materials for electronic packaging

    NASA Astrophysics Data System (ADS)

    Liu, Zongrong

    The aim of this dissertation is to develop electrically or thermally conductive materials that are needed for electronic packaging and microelectronic cooling. These materials are in the form of coatings and are made from pastes. The research work encompasses paste formulation, studying the process of converting a paste to a conductive material, relating the processing conditions to the structure and performance, and evaluating performance attributes that are relevant to the application of these conductive materials. The research has resulted in new information that is valuable to the microelectronic industry. Work on electrically conductive materials emphasizes the development of electrical interconnection materials in the form of air-firable glass-free silver-based electrically conductive thick films, which use the Ti-Al alloy as the binder and are in contrast to conventional films that use glass as the binder. The air-firability, as enabled by minor additions of tin and zinc to the paste, is in contrast to previous glass-free films that are not firable. The recommended firing condition is 930°C in air. The organic vehicle in the paste comprises ethyl cellulose, which undergoes thermal decomposition during burnout of the paste. The ethyl cellulose is dissolved in ether, which facilitates the burnout. Excessive ethyl cellulose hinders the burnout. A higher heating rate results in more residue after burnout. The presence of silver particles facilitates drying and burnout. Firing in air gives lower resistivity than firing in oxygen. Firing in argon gives poor films. Compared to conventional films that use glass as the binder, these films, when appropriately fired, exhibit lower electrical resistivity (2.5 x 10-6 O.cm) and higher scratch resistance. Work on thermally conductive materials addresses thermal interface materials, which are materials placed at the interface between a heat sink and a heat source for the purpose of improving the thermal contact. Heat

  7. Lithium ion conducting ionic electrolytes

    DOEpatents

    Angell, C.A.; Xu, K.; Liu, C.

    1996-01-16

    A liquid, predominantly lithium-conducting, ionic electrolyte is described which has exceptionally high conductivity at temperatures of 100 C or lower, including room temperature. It comprises molten lithium salts or salt mixtures in which a small amount of an anionic polymer lithium salt is dissolved to stabilize the liquid against recrystallization. Further, a liquid ionic electrolyte which has been rubberized by addition of an extra proportion of anionic polymer, and which has good chemical and electrochemical stability, is described. This presents an attractive alternative to conventional salt-in-polymer electrolytes which are not cationic conductors. 4 figs.

  8. Lithium ion conducting ionic electrolytes

    DOEpatents

    Angell, C. Austen; Xu, Kang; Liu, Changle

    1996-01-01

    A liquid, predominantly lithium-conducting, ionic electrolyte is described which has exceptionally high conductivity at temperatures of 100.degree. C. or lower, including room temperature. It comprises molten lithium salts or salt mixtures in which a small amount of an anionic polymer lithium salt is dissolved to stabilize the liquid against recrystallization. Further, a liquid ionic electrolyte which has been rubberized by addition of an extra proportion of anionic polymer, and which has good chemical and electrochemical stability, is described. This presents an attractive alternative to conventional salt-in-polymer electrolytes which are not cationic conductors.

  9. Boron addition to alloys

    SciTech Connect

    Coad, B. C.

    1985-08-20

    A process for addition of boron to an alloy which involves forming a melt of the alloy and a reactive metal, selected from the group consisting of aluminum, titanium, zirconium and mixtures thereof to the melt, maintaining the resulting reactive mixture in the molten state and reacting the boric oxide with the reactive metal to convert at least a portion of the boric oxide to boron which dissolves in the resulting melt, and to convert at least portion of the reactive metal to the reactive metal oxide, which oxide remains with the resulting melt, and pouring the resulting melt into a gas stream to form a first atomized powder which is subsequently remelted with further addition of boric oxide, re-atomized, and thus reprocessed to convert essentially all the reactive metal to metal oxide to produce a powdered alloy containing specified amounts of boron.

  10. Tackifier for addition polyimides

    NASA Technical Reports Server (NTRS)

    Butler, J. M.; St.clair, T. L.

    1980-01-01

    A modification to the addition polyimide, LaRC-160, was prepared to improve tack and drape and increase prepeg out-time. The essentially solventless, high viscosity laminating resin is synthesized from low cost liquid monomers. The modified version takes advantage of a reactive, liquid plasticizer which is used in place of solvent and helps solve a major problem of maintaining good prepeg tack and drape, or the ability of the prepeg to adhere to adjacent plies and conform to a desired shape during the lay up process. This alternate solventless approach allows both longer life of the polymer prepeg and the processing of low void laminates. This approach appears to be applicable to all addition polyimide systems.

  11. Vinyl capped addition polyimides

    NASA Technical Reports Server (NTRS)

    Vannucci, Raymond D. (Inventor); Malarik, Diane C. (Inventor); Delvigs, Peter (Inventor)

    1991-01-01

    Polyimide resins (PMR) are generally useful where high strength and temperature capabilities are required (at temperatures up to about 700 F). Polyimide resins are particularly useful in applications such as jet engine compressor components, for example, blades, vanes, air seals, air splitters, and engine casing parts. Aromatic vinyl capped addition polyimides are obtained by reacting a diamine, an ester of tetracarboxylic acid, and an aromatic vinyl compound. Low void materials with improved oxidative stability when exposed to 700 F air may be fabricated as fiber reinforced high molecular weight capped polyimide composites. The aromatic vinyl capped polyimides are provided with a more aromatic nature and are more thermally stable than highly aliphatic, norbornenyl-type end-capped polyimides employed in PMR resins. The substitution of aromatic vinyl end-caps for norbornenyl end-caps in addition polyimides results in polymers with improved oxidative stability.

  12. [Biologically active food additives].

    PubMed

    Velichko, M A; Shevchenko, V P

    1998-07-01

    More than half out of 40 projects for the medical science development by the year of 2000 have been connected with the bio-active edible additives that are called "the food of XXI century", non-pharmacological means for many diseases. Most of these additives--nutricevtics and parapharmacevtics--are intended for the enrichment of food rations for the sick or healthy people. The ecologicaly safest and most effective are combined domestic adaptogens with immuno-modulating and antioxidating action that give anabolic and stimulating effect,--"leveton", "phytoton" and "adapton". The MKTs-229 tablets are residue discharge means. For atherosclerosis and general adiposis they recommend "tsar tablets" and "aiconol (ikhtien)"--on the base of cod-liver oil or "splat" made out of seaweed (algae). All these preparations have been clinically tested and received hygiene certificates from the Institute of Dietology of the Russian Academy of Medical Science. PMID:9752776

  13. Oxidation and sulfidation resistant alloys with silicon additions

    SciTech Connect

    Dunning, John S.; Alman, David E.; Poston, J.A., Jr.; Siriwardane, R.

    2003-01-01

    The Albany Research Center (ARC) has considerable experience in developing lean chromium, austenitic stainless steels with improved high temperature oxidation resistance. Using basic alloy design principles, a baseline composition of Fe-16Cr-16Ni-2Mn-1Mo alloys with Si and Al addition at a maximum of 5 weight percent was selected for potential application at temperatures above 700ºC for supercritical and ultra-supercritical power plant application. The alloys were fully austenitic. Cyclic oxidation tests in air for 1000 hours were carried out on alloys with Si only or combined Si and Al additions in the temperature range 700ºC to 800ºC. Oxidation resistances of alloys with Si only additions were outstanding, particularly at 800ºC (i.e., these alloys possessed weight gains 4 times less than a standard type-304 alloy). In addition, Si alloys pre-oxidized at 800ºC, showed a zero weight gain in subsequent testing for 1000 hours at 700ºC. Similar improvements were observed for Si only alloy after H2S exposure at 700ºC compared with type 304 stainless steel. SEM and ESCA analysis of the oxide films and base material at the oxide/base metal interface were conducted to study potential rate controlling mechanisms at ARC. Depth profile analysis and element concentration profiles (argon ion etching/x-ray photoelectron spectroscopy) were conducted on oxidized specimens and base material at the National Energy Technology Laboratory.

  14. Electrophilic addition of astatine

    SciTech Connect

    Norseev, Yu.V.; Vasaros, L.; Nhan, D.D.; Huan, N.K.

    1988-03-01

    It has been shown for the first time that astatine is capable of undergoing addition reactions to unsaturated hydrocarbons. A new compound of astatine, viz., ethylene astatohydrin, has been obtained, and its retention numbers of squalane, Apiezon, and tricresyl phosphate have been found. The influence of various factors on the formation of ethylene astatohydrin has been studied. It has been concluded on the basis of the results obtained that the univalent cations of astatine in an acidic medium is protonated hypoastatous acid.

  15. Hydrocarbon fuel additive

    SciTech Connect

    Ambrogio, S.

    1989-02-28

    This patent describes the method of fuel storage or combustion, wherein the fuel supply contains small amounts of water, the step of adding to the fuel supply an additive comprising a blend of a hydrophilic agent chosen from the group of ethylene glycol, n-butyl alcohol, and cellosolve in the range of 22-37% by weight; ethoxylated nonylphenol in the range of 26-35% by weight; nonylphenol polyethylene glycol ether in the range of 32-43% by weight.

  16. Functional Generalized Additive Models.

    PubMed

    McLean, Mathew W; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

    2014-01-01

    We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online. PMID:24729671

  17. Highly elastic conductive polymeric MEMS

    NASA Astrophysics Data System (ADS)

    Ruhhammer, J.; Zens, M.; Goldschmidtboeing, F.; Seifert, A.; Woias, P.

    2015-02-01

    Polymeric structures with integrated, functional microelectrical mechanical systems (MEMS) elements are increasingly important in various applications such as biomedical systems or wearable smart devices. These applications require highly flexible and elastic polymers with good conductivity, which can be embedded into a matrix that undergoes large deformations. Conductive polydimethylsiloxane (PDMS) is a suitable candidate but is still challenging to fabricate. Conductivity is achieved by filling a nonconductive PDMS matrix with conductive particles. In this work, we present an approach that uses new mixing techniques to fabricate conductive PDMS with different fillers such as carbon black, silver particles, and multiwalled carbon nanotubes. Additionally, the electrical properties of all three composites are examined under continuous mechanical stress. Furthermore, we present a novel, low-cost, simple three-step molding process that transfers a micro patterned silicon master into a polystyrene (PS) polytetrafluoroethylene (PTFE) replica with improved release features. This PS/PTFE mold is used for subsequent structuring of conductive PDMS with high accuracy. The non sticking characteristics enable the fabrication of delicate structures using a very soft PDMS, which is usually hard to release from conventional molds. Moreover, the process can also be applied to polyurethanes and various other material combinations.

  18. Electrically conductive composite material

    DOEpatents

    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.

  19. Electrically conductive composite material

    DOEpatents

    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.

  20. Conductive mechanism in manganite materials

    NASA Astrophysics Data System (ADS)

    Liu, Xianming; Zhu, Hong; Zhang, Yuheng

    2002-01-01

    We describe a model in which f(T)=M(T)/Mmax represents both the fraction of the itinerant electron density in the double-exchange (DE) theory and the magnetization σ in the current carrier density collapse (CCDC) theory. With this model, we have checked the DE and CCDC theories with our experimental results of the transport behavior. The DE theory yields agreement with the experimental resistivity excellently, in which the conductivity is the sum of the polaronic and itinerant electronic conductivity for the insulator-metal transition regime. The fitting curves of the resistivity by the CCDC theory deviate from the experiment seriously. This might be caused by the improper assumption of the temperature-dependent carrier density and the temperature-independent carrier mobility. Therefore, it is concluded that the DE theory is more suitable to explain the conductive mechanism in perovskite manganites.

  1. Conductive Channel for Energy Transmission

    NASA Astrophysics Data System (ADS)

    Apollonov, Victor V.

    2011-11-01

    For many years the attempts to create conductive channels of big length were taken in order to study the upper atmosphere and to settle special tasks, related to energy transmission. There upon the program of creation of "Impulsar" represents a great interest, as this program in a combination with high-voltage high repetition rate electrical source can be useful to solve the above mentioned problems (N. Tesla ideas for the days of high power lasers). The principle of conductive channel production can be shortly described as follows. The "Impulsar"—laser jet engine vehicle—propulsion take place under the influence of powerful high repetition rate pulse-periodic laser radiation. In the experiments the CO2—laser and solid state Nd:YAG laser systems had been used. Active impulse appears thanks to air breakdown (<30 km) or to the breakdown of ablated material on the board (>30 km), placed in the vicinity of the focusing mirror-acceptor of the breakdown waves. With each pulse of powerful laser the device rises up, leaving a bright and dense trace of products with high degree of ionization and metallization by conductive nano-particles due to ablation. Conductive dust plasma properties investigation in our experiments was produced by two very effective approaches: high power laser controlled ablation and by explosion of wire. Experimental and theoretical results of conductive canal modeling will be presented. The estimations show that with already experimentally demonstrated figures of specific thrust impulse the lower layers of the Ionosphere can be reached in several ten seconds that is enough to keep the high level of channel conductivity and stability with the help of high repetition rate high voltage generator. Some possible applications for new technology are highlighted.

  2. An experiment in software reliability

    NASA Technical Reports Server (NTRS)

    Dunham, J. R.; Pierce, J. L.

    1986-01-01

    The results of a software reliability experiment conducted in a controlled laboratory setting are reported. The experiment was undertaken to gather data on software failures and is one in a series of experiments being pursued by the Fault Tolerant Systems Branch of NASA Langley Research Center to find a means of credibly performing reliability evaluations of flight control software. The experiment tests a small sample of implementations of radar tracking software having ultra-reliability requirements and uses n-version programming for error detection, and repetitive run modeling for failure and fault rate estimation. The experiment results agree with those of Nagel and Skrivan in that the program error rates suggest an approximate log-linear pattern and the individual faults occurred with significantly different error rates. Additional analysis of the experimental data raises new questions concerning the phenomenon of interacting faults. This phenomenon may provide one explanation for software reliability decay.

  3. Siloxane containing addition polyimides

    NASA Technical Reports Server (NTRS)

    Maudgal, S.; St. Clair, T. L.

    1984-01-01

    Addition polyimide oligomers have been synthesized from bis(gamma-aminopropyl) tetramethyldisiloxane and 3, 3', 4, 4'-benzophenonetetracarboxylic dianhydride using a variety of latent crosslinking groups as endcappers. The prepolymers were isolated and characterized for solubility (in amide, chlorinated and ether solvents), melt flow and cure properties. The most promising systems, maleimide and acetylene terminated prepolymers, were selected for detailed study. Graphite cloth reinforced composites were prepared and properties compared with those of graphite/Kerimid 601, a commercially available bismaleimide. Mixtures of the maleimide terminated system with Kerimid 601, in varying proportions, were also studied.

  4. Oil additive process

    SciTech Connect

    Bishop, H.

    1988-10-18

    This patent describes a method of making an additive comprising: (a) adding 2 parts by volume of 3% sodium hypochlorite to 45 parts by volume of diesel oil fuel to form a sulphur free fuel, (b) removing all water and foreign matter formed by the sodium hypochlorite, (c) blending 30 parts by volume of 24% lead naphthanate with 15 parts by volume of the sulphur free fuel, 15 parts by volume of light-weight material oil to form a blended mixture, and (d) heating the blended mixture slowly and uniformly to 152F.

  5. The Additive Coloration of Alkali Halides

    ERIC Educational Resources Information Center

    Jirgal, G. H.; and others

    1969-01-01

    Describes the construction and use of an inexpensive, vacuum furnace designed to produce F-centers in alkali halide crystals by additive coloration. The method described avoids corrosion or contamination during the coloration process. Examination of the resultant crystals is discussed and several experiments using additively colored crystals are…

  6. Sufficient dimension reduction with additional information.

    PubMed

    Hung, Hung; Liu, Chih-Yen; Horng-Shing Lu, Henry

    2016-07-01

    Sufficient dimension reduction is widely applied to help model building between the response [Formula: see text] and covariate [Formula: see text] In some situations, we also collect additional covariate [Formula: see text] that has better performance in predicting [Formula: see text], but has a higher obtaining cost, than [Formula: see text] While constructing a predictive model for [Formula: see text] based on [Formula: see text] is straightforward, this strategy is not applicable since [Formula: see text] is not available for future observations in which the constructed model is to be applied. As a result, the aim of the study is to build a predictive model for [Formula: see text] based on [Formula: see text] only, where the available data is [Formula: see text] A naive method is to conduct analysis using [Formula: see text] directly, but ignoring [Formula: see text] can cause the problem of inefficiency. On the other hand, it is not trivial to utilize the information of [Formula: see text] to infer [Formula: see text], either. In this article, we propose a two-stage dimension reduction method for [Formula: see text] that is able to utilize the information of [Formula: see text] In the breast cancer data, the risk score constructed from the two-stage method can well separate patients with different survival experiences. In the Pima data, the two-stage method requires fewer components to infer the diabetes status, while achieving higher classification accuracy than the conventional method. PMID:26704765

  7. E-Textbooks and Students' Learning Experiences

    ERIC Educational Resources Information Center

    Sun, Jun; Flores, Javier; Tanguma, Jesus

    2012-01-01

    The contribution of the e-textbooks can be enormous considering their additional supporting features, but adoption has not crystallized yet. This study examines the relevant experiences of college students in terms of how the use of e-textbooks may enhance their learning. A survey study was conducted to measure the perceptions of each student on…

  8. Structure, ionic Conductivity and mobile Carrier Density in Fast Ionic Conducting Chalcogenide Glasses

    SciTech Connect

    Wenlong Yao

    2006-12-12

    This thesis consists of six sections. The first section gives the basic research background on the ionic conduction mechanism in glass, polarization in the glass, and the method of determining the mobile carrier density in glass. The proposed work is also included in this section. The second section is a paper that characterizes the structure of MI + M{sub 2}S + (0.1 Ga{sub 2}S{sub 3} + 0.9 GeS{sub 2}) (M = Li, Na, K and Cs) glasses using Raman and IR spectroscopy. Since the ionic radius plays an important role in determining the ionic conductivity in glasses, the glass forming range for the addition of different alkalis into the basic glass forming system 0.1 Ga{sub 2}S{sub 3} + 0.9 GeS{sub 2} was studied. The study found that the change of the alkali radius for the same nominal composition causes significant structure change to the glasses. The third section is a paper that investigates the ionic conductivity of MI + M{sub 2}S + (0.1Ga{sub 2}S{sub 3} + 0.9 GeS{sub 2}) (M = Li, Na, K and Cs) glasses system. Corresponding to the compositional changes in these fast ionic conducting glasses, the ionic conductivity shows changes due to the induced structural changes. The ionic radius effect on the ionic conductivity in these glasses was investigated. The fourth section is a paper that examines the mobile carrier density based upon the measurements of space charge polarization. For the first time, the charge carrier number density in fast ionic conducting chalcogenide glasses was determined. The experimental impedance data were fitted using equivalent circuits and the obtained parameters were used to determine the mobile carrier density. The influence of mobile carrier density and mobility on the ionic conductivity was separated. The fifth section is a paper that studies the structures of low-alkali-content Na{sub 2}S + B{sub 2}S{sub 3} (x {le} 0.2) glasses by neutron and synchrotron x-ray diffraction. Similar results were obtained both in neutron and synchrotron x

  9. Performance Boosting Additive

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Mainstream Engineering Corporation was awarded Phase I and Phase II contracts from Goddard Space Flight Center's Small Business Innovation Research (SBIR) program in early 1990. With support from the SBIR program, Mainstream Engineering Corporation has developed a unique low cost additive, QwikBoost (TM), that increases the performance of air conditioners, heat pumps, refrigerators, and freezers. Because of the energy and environmental benefits of QwikBoost, Mainstream received the Tibbetts Award at a White House Ceremony on October 16, 1997. QwikBoost was introduced at the 1998 International Air Conditioning, Heating, and Refrigeration Exposition. QwikBoost is packaged in a handy 3-ounce can (pressurized with R-134a) and will be available for automotive air conditioning systems in summer 1998.

  10. Sewage sludge additive

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Mueller, W. A.; Ingham, J. D. (Inventor)

    1980-01-01

    The additive is for a raw sewage treatment process of the type where settling tanks are used for the purpose of permitting the suspended matter in the raw sewage to be settled as well as to permit adsorption of the dissolved contaminants in the water of the sewage. The sludge, which settles down to the bottom of the settling tank is extracted, pyrolyzed and activated to form activated carbon and ash which is mixed with the sewage prior to its introduction into the settling tank. The sludge does not provide all of the activated carbon and ash required for adequate treatment of the raw sewage. It is necessary to add carbon to the process and instead of expensive commercial carbon, coal is used to provide the carbon supplement.

  11. Perspectives on Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Bourell, David L.

    2016-07-01

    Additive manufacturing (AM) has skyrocketed in visibility commercially and in the public sector. This article describes the development of this field from early layered manufacturing approaches of photosculpture, topography, and material deposition. Certain precursors to modern AM processes are also briefly described. The growth of the field over the last 30 years is presented. Included is the standard delineation of AM technologies into seven broad categories. The economics of AM part generation is considered, and the impacts of the economics on application sectors are described. On the basis of current trends, the future outlook will include a convergence of AM fabricators, mass-produced AM fabricators, enabling of topology optimization designs, and specialization in the AM legal arena. Long-term developments with huge impact are organ printing and volume-based printing.

  12. New addition curing polyimides

    NASA Technical Reports Server (NTRS)

    Frimer, Aryeh A.; Cavano, Paul

    1991-01-01

    In an attempt to improve the thermal-oxidative stability (TOS) of PMR-type polymers, the use of 1,4-phenylenebis (phenylmaleic anhydride) PPMA, was evaluated. Two series of nadic end-capped addition curing polyimides were prepared by imidizing PPMA with either 4,4'-methylene dianiline or p-phenylenediamine. The first resulted in improved solubility and increased resin flow while the latter yielded a compression molded neat resin sample with a T(sub g) of 408 C, close to 70 C higher than PME-15. The performance of these materials in long term weight loss studies was below that of PMR-15, independent of post-cure conditions. These results can be rationalized in terms of the thermal lability of the pendant phenyl groups and the incomplete imidization of the sterically congested PPMA. The preparation of model compounds as well as future research directions are discussed.

  13. High conductance surge cable

    DOEpatents

    Murray, Matthew M.; Wilfong, Dennis H.; Lomax, Ralph E.

    1998-01-01

    An electrical cable for connecting transient voltage surge suppressers to ectrical power panels. A strip of electrically conductive foil defines a longitudinal axis, with a length of an electrical conductor electrically attached to the metallic foil along the longitudinal axis. The strip of electrically conductive foil and the length of an electrical conductor are covered by an insulating material. For impedance matching purposes, triangular sections can be removed from the ends of the electrically conductive foil at the time of installation.

  14. High conductance surge cable

    DOEpatents

    Murray, M.M.; Wilfong, D.H.; Lomax, R.E.

    1998-12-08

    An electrical cable for connecting transient voltage surge suppressors to electrical power panels. A strip of electrically conductive foil defines a longitudinal axis, with a length of an electrical conductor electrically attached to the metallic foil along the longitudinal axis. The strip of electrically conductive foil and the length of an electrical conductor are covered by an insulating material. For impedance matching purposes, triangular sections can be removed from the ends of the electrically conductive foil at the time of installation. 6 figs.

  15. Synthesis of novel electrically conducting polymers: Potential conducting Langmuir-Blodgett films and conducting polymers on defined surfaces

    NASA Technical Reports Server (NTRS)

    Zimmer, Hans

    1993-01-01

    Based on previous results involving thiophene derived electrically conducting polymers in which it was shown that thiophene, 3-substituted thiophenes, furans, and certain oligomers of these compounds showed electrical conductivity after polymerization. The conductivity was in the order of up to 500 S/cm. In addition, these polymers showed conductivity without being doped and most of all they were practically inert toward ambient conditions. They even could be used in aqueous media. With these findings as a guide, a number of 3-long-chain-substituted thiophenes and 1-substituted-3-long-chain substituted pyrrols were synthesized as monomers for potential polymeric electrically conducting Langmuir-Blodgett films.

  16. Electrically conductive cellulose composite

    DOEpatents

    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.

  17. Cooling Rate Determination in Additively Manufactured Aluminum Alloy 2219

    NASA Astrophysics Data System (ADS)

    Brice, Craig A.; Dennis, Noah

    2015-05-01

    Metallic additive manufacturing processes generally utilize a conduction mode, welding-type approach to create beads of deposited material that can be arranged into a three-dimensional structure. As with welding, the cooling rates in the molten pool are relatively rapid compared to traditional casting techniques. Determination of the cooling rate in the molten pool is critical for predicting the solidified microstructure and resultant properties. In this experiment, wire-fed electron beam additive manufacturing was used to melt aluminum alloy 2219 under different thermal boundary conditions. The dendrite arm spacing was measured in the remelted material, and this information was used to estimate cooling rates in the molten pool based on established empirical relationships. The results showed that the thermal boundary conditions have a significant effect on the resulting cooling rate in the molten pool. When thermal conduction is limited due to a small thermal sink, the dendrite arm spacing varies between 15 and 35 µm. When thermal conduction is active, the dendrite arm spacing varies between 6 and 12 µm. This range of dendrite arm spacing implies cooling rates ranging from 5 to 350 K/s. Cooling rates can vary greatly as thermal conditions change during deposition. A cooling rate at the higher end of the range could lead to significant deviation from microstructural equilibrium during solidification.

  18. Conformational gating of DNA conductance

    PubMed Central

    Artés, Juan Manuel; Li, Yuanhui; Qi, Jianqing; Anantram, M. P.; Hihath, Joshua

    2015-01-01

    DNA is a promising molecule for applications in molecular electronics because of its unique electronic and self-assembly properties. Here we report that the conductance of DNA duplexes increases by approximately one order of magnitude when its conformation is changed from the B-form to the A-form. This large conductance increase is fully reversible, and by controlling the chemical environment, the conductance can be repeatedly switched between the two values. The conductance of the two conformations displays weak length dependencies, as is expected for guanine-rich sequences, and can be fit with a coherence-corrected hopping model. These results are supported by ab initio electronic structure calculations that indicate that the highest occupied molecular orbital is more disperse in the A-form DNA case. These results demonstrate that DNA can behave as a promising molecular switch for molecular electronics applications and also provide additional insights into the huge dispersion of DNA conductance values found in the literature. PMID:26648400

  19. Conformational gating of DNA conductance.

    PubMed

    Artés, Juan Manuel; Li, Yuanhui; Qi, Jianqing; Anantram, M P; Hihath, Joshua

    2015-01-01

    DNA is a promising molecule for applications in molecular electronics because of its unique electronic and self-assembly properties. Here we report that the conductance of DNA duplexes increases by approximately one order of magnitude when its conformation is changed from the B-form to the A-form. This large conductance increase is fully reversible, and by controlling the chemical environment, the conductance can be repeatedly switched between the two values. The conductance of the two conformations displays weak length dependencies, as is expected for guanine-rich sequences, and can be fit with a coherence-corrected hopping model. These results are supported by ab initio electronic structure calculations that indicate that the highest occupied molecular orbital is more disperse in the A-form DNA case. These results demonstrate that DNA can behave as a promising molecular switch for molecular electronics applications and also provide additional insights into the huge dispersion of DNA conductance values found in the literature. PMID:26648400

  20. MY 20 YEARS EXPERIENCE IN CONDUCTING ENVIRONMENTAL HEALTH STUDIES IN CHINA: (1) STUDIES ON LUNG CANCER AND INDOOR AIR POLLUTION IN YUNNAN AND (2) HEALTH EFFECTS OF ARSENIC EXPOSURE VIA DRINKING WATER IN INNER MONGOLIA

    EPA Science Inventory

    As a research health scientist at U.S. Environmental Protection Agency, I have been very fortunate to have opportunities to work as a principal investigator for two major environmental health research projects. The first study was conducted in 1983-1996 under a formal U.S.-China ...

  1. Codes of Conduct

    ERIC Educational Resources Information Center

    Million, June

    2004-01-01

    Most schools have a code of conduct, pledge, or behavioral standards, set by the district or school board with the school community. In this article, the author features some schools that created a new vision of instilling code of conducts to students based on work quality, respect, safety and courtesy. She suggests that communicating the code…

  2. Electrically conductive diamond electrodes

    DOEpatents

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

    2009-05-19

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

  3. Conductive Critical Thinking

    ERIC Educational Resources Information Center

    Paetkau, Mark

    2007-01-01

    One of my goals as an instructor is to teach students critical thinking skills. This paper presents an example of a student-led discussion of heat conduction at the first-year level. Heat loss from a human head is calculated using conduction and radiation models. The results of these plausible (but wrong) models of heat transfer contradict what…

  4. Conductive Education Evaluated.

    ERIC Educational Resources Information Center

    Stukat, Karl Gustav

    1995-01-01

    This paper evaluates two research projects concerned with conductive education for children with cerebral palsy, one in Germany and the other in the United Kingdom. Issues of generalizability and drawing causal conclusions are raised. The paper finds that neither the most sanguine expectations nor the worst misgivings about conductive education…

  5. Conductive fabric seal

    DOEpatents

    Livesay, Ronald Jason; Mason, Brandon William; Kuhn, Michael Joseph; Rowe, Nathan Carl

    2015-10-13

    Disclosed are several examples of a system and method for detecting if an article is being tampered with. Included is a covering made of a substrate that is coated with a layer of an electrically conductive material that forms an electrically conductive surface having an electrical resistance. The covering is configured to at least partially encapsulate the article such that the article cannot be tampered with, without modifying the electrical resistance of the electrically conductive surface of the covering. A sensing device is affixed to the electrically conductive surface of the covering and the sensing device monitors the condition of the covering by producing a signal that is indicative of the electrical resistance of the electrically conductive surface of the covering. A measured electrical resistance that differs from a nominal electrical resistance is indicative of a covering that is being tampered with and an alert is communicated to an observer.

  6. An Additive Manufacturing Test Artifact

    PubMed Central

    Moylan, Shawn; Slotwinski, John; Cooke, April; Jurrens, Kevin; Donmez, M Alkan

    2014-01-01

    A test artifact, intended for standardization, is proposed for the purpose of evaluating the performance of additive manufacturing (AM) systems. A thorough analysis of previously proposed AM test artifacts as well as experience with machining test artifacts have inspired the design of the proposed test artifact. This new artifact is designed to provide a characterization of the capabilities and limitations of an AM system, as well as to allow system improvement by linking specific errors measured in the test artifact to specific sources in the AM system. The proposed test artifact has been built in multiple materials using multiple AM technologies. The results of several of the builds are discussed, demonstrating how the measurement results can be used to characterize and improve a specific AM system. PMID:26601039

  7. An Additive Manufacturing Test Artifact.

    PubMed

    Moylan, Shawn; Slotwinski, John; Cooke, April; Jurrens, Kevin; Donmez, M Alkan

    2014-01-01

    A test artifact, intended for standardization, is proposed for the purpose of evaluating the performance of additive manufacturing (AM) systems. A thorough analysis of previously proposed AM test artifacts as well as experience with machining test artifacts have inspired the design of the proposed test artifact. This new artifact is designed to provide a characterization of the capabilities and limitations of an AM system, as well as to allow system improvement by linking specific errors measured in the test artifact to specific sources in the AM system. The proposed test artifact has been built in multiple materials using multiple AM technologies. The results of several of the builds are discussed, demonstrating how the measurement results can be used to characterize and improve a specific AM system. PMID:26601039

  8. The effect of silane addition timing on mixing processability and properties of silica reinforced rubber compound

    NASA Astrophysics Data System (ADS)

    Jeong, Hee-Hoon; Jin, Hyun-Ho; Ha, Sung-Ho; Jang, Suk-Hee; Kang, Yong-Gu; Han, Min-Hyun

    2016-03-01

    A series of experiments were performed to determine an optimum balance between processability and performance of a highly loaded silica compound. The experiments evaluated 4 different silane injection times. All mixing related to silane addition was conducted with a scaled up "Tandem" mixer line. With exception to silane addition timing, almost all operating conditions were controlled between experimental features. It was found that when the silane addition was introduced earlier in the mixing cycle both the reaction was more complete and the bound rubber content was higher. But processability indicators such as sheet forming and Mooney plasticity were negatively impacted. On the other hand, as silane injection was delayed to later in the mixing process the filler dispersion and good sheet forming was improved. However both the bound rubber content and Silane reaction completion were decreased. With the changes in silane addition time, the processability and properties of a silica compound can be controlled.

  9. Gross decontamination experiment report

    SciTech Connect

    Mason, R.; Kinney, K.; Dettorre, J.; Gilbert, V.

    1983-07-01

    A Gross Decontamination Experiment was conducted on various levels and surfaces of the TMI - Unit 2 reactor building in March 1982. The polar crane, D-rings, missile shields, refueling canals, refueling bridges, equipment, and elevations 305' and 347'-6'' were flushed with low pressure water. Additionally, floor surfaces on elevation 305' and floor surfaces and major pieces of equipment on elevation 347'-6'' were sprayed with high pressure water. Selective surfaces were decontaminated with a mechanical scrubber and chemicals. Strippable coating was tested and evaluated on equipment and floor surfaces. The effectiveness, efficiency, and safety of several decontamination techniques were established for the large, complex decontamination effort. Various decontamination equipment was evaluated and its effectiveness was documented. Decontamination training and procedures were documented and evaluated, as were the support system and organization for the experiment.

  10. Influence of residue and nitrogen fertilizer additions on carbon mineralization in soils with different texture and cropping histories

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To improve our ability to predict SOC mineralization response to residue and N additions in soils with different inherent and dynamic organic matter properties, a 330-day incubation was conducted using soil sampled from two long-term experiments (clay loam Mollisols in Iowa [IAsoil] and silt loam Ul...

  11. Nanocarbonic transparent conductive films.

    PubMed

    Roth, Siegmar; Park, Hye Jin

    2010-07-01

    This tutorial review discusses the contradictory material properties of electrical conductivity and optical transparency for the examples of graphene films and carbon nanotube networks. It is argued that for homogeneous films both properties are linked by basic laws of physics and that for perfect monoatomic layers conductivity and transparency can be calculated from the fine structure constant. To beat these limitations, inhomogeneous films are required, such as graphene with an array of holes or nanotube networks. An overview is given on literature values of transparency and conductivity, both for graphene films and for nanotube networks. PMID:20502813

  12. Aeromonas hydrophila produces conductive nanowires.

    PubMed

    Castro, Laura; Vera, Mario; Muñoz, Jesús Ángel; Blázquez, María Luisa; González, Felisa; Sand, Wolfgang; Ballester, Antonio

    2014-11-01

    Aeromonas hydrophila is a facultative anaerobe which, under conditions of oxygen depletion, uses Fe(III) as electron acceptor. A. hydrophila produces pili during growth with Fe(III). The study was focused on the characterization of the morphology, the electrical properties and the nature of the bacterial pili. Scanning electron microscopy and conductive-probe atomic force microscopy revealed the presence of filaments between cells and substrate and their conductive nature. Our results indicate that pili of A. hydrophila strain A might serve as biological nanowires, transferring electrons from the cell surface to the surface of Fe(III) oxides and, in addition, the possibility of playing a role in inter/intra species signaling. Quorum sensing (QS) is recognized as one of the main regulatory ways for extracellular polymeric substances (EPS) production and biofilm formation. We present evidence that nanowire formation can be regulated by addition of synthetic acyl-homoserine lactones (AHL). These conductive pili may be involved in various interactions, and their protein components might be usable in the future for biotechnological approaches in materials science. PMID:25283724

  13. The Role of Additional Pulses in Electropermeabilization Protocols

    PubMed Central

    Suárez, Cecilia; Soba, Alejandro; Maglietti, Felipe; Olaiz, Nahuel; Marshall, Guillermo

    2014-01-01

    Electropermeabilization (EP) based protocols such as those applied in medicine, food processing or environmental management, are well established and widely used. The applied voltage, as well as tissue electric conductivity, are of utmost importance for assessing final electropermeabilized area and thus EP effectiveness. Experimental results from literature report that, under certain EP protocols, consecutive pulses increase tissue electric conductivity and even the permeabilization amount. Here we introduce a theoretical model that takes into account this effect in the application of an EP-based protocol, and its validation with experimental measurements. The theoretical model describes the electric field distribution by a nonlinear Laplace equation with a variable conductivity coefficient depending on the electric field, the temperature and the quantity of pulses, and the Penne's Bioheat equation for temperature variations. In the experiments, a vegetable tissue model (potato slice) is used for measuring electric currents and tissue electropermeabilized area in different EP protocols. Experimental measurements show that, during sequential pulses and keeping constant the applied voltage, the electric current density and the blackened (electropermeabilized) area increase. This behavior can only be attributed to a rise in the electric conductivity due to a higher number of pulses. Accordingly, we present a theoretical modeling of an EP protocol that predicts correctly the increment in the electric current density observed experimentally during the addition of pulses. The model also demonstrates that the electric current increase is due to a rise in the electric conductivity, in turn induced by temperature and pulse number, with no significant changes in the electric field distribution. The EP model introduced, based on a novel formulation of the electric conductivity, leads to a more realistic description of the EP phenomenon, hopefully providing more accurate

  14. The role of additional pulses in electropermeabilization protocols.

    PubMed

    Suárez, Cecilia; Soba, Alejandro; Maglietti, Felipe; Olaiz, Nahuel; Marshall, Guillermo

    2014-01-01

    Electropermeabilization (EP) based protocols such as those applied in medicine, food processing or environmental management, are well established and widely used. The applied voltage, as well as tissue electric conductivity, are of utmost importance for assessing final electropermeabilized area and thus EP effectiveness. Experimental results from literature report that, under certain EP protocols, consecutive pulses increase tissue electric conductivity and even the permeabilization amount. Here we introduce a theoretical model that takes into account this effect in the application of an EP-based protocol, and its validation with experimental measurements. The theoretical model describes the electric field distribution by a nonlinear Laplace equation with a variable conductivity coefficient depending on the electric field, the temperature and the quantity of pulses, and the Penne's Bioheat equation for temperature variations. In the experiments, a vegetable tissue model (potato slice) is used for measuring electric currents and tissue electropermeabilized area in different EP protocols. Experimental measurements show that, during sequential pulses and keeping constant the applied voltage, the electric current density and the blackened (electropermeabilized) area increase. This behavior can only be attributed to a rise in the electric conductivity due to a higher number of pulses. Accordingly, we present a theoretical modeling of an EP protocol that predicts correctly the increment in the electric current density observed experimentally during the addition of pulses. The model also demonstrates that the electric current increase is due to a rise in the electric conductivity, in turn induced by temperature and pulse number, with no significant changes in the electric field distribution. The EP model introduced, based on a novel formulation of the electric conductivity, leads to a more realistic description of the EP phenomenon, hopefully providing more accurate

  15. Electrically conductive polyimides containing silver trifluoroacetylacetonate

    NASA Technical Reports Server (NTRS)

    Rancourt, James D. (Inventor); Stoakley, Diane M. (Inventor); Caplan, Maggie L. (Inventor); St. Clair, Anne K. (Inventor); Taylor, Larry T. (Inventor)

    1996-01-01

    Polyimides with enhanced electrical conductivity are produced by adding a silver ion-containing additive to the polyamic acid resin formed by the condensation of an aromatic dianhydride with an aromatic diamine. After thermal treatment the resulting polyimides had surface conductivities in the range of 1.7.times.10.sup.-3 4.5 .OMEGA..sup.-1 making them useful in low the electronics industry as flexible, electrically conductive polymeric films and coatings.

  16. Cardiac Conduction through Engineered Tissue

    PubMed Central

    Choi, Yeong-Hoon; Stamm, Christof; Hammer, Peter E.; Kwaku, Kevin F.; Marler, Jennifer J.; Friehs, Ingeborg; Jones, Mara; Rader, Christine M.; Roy, Nathalie; Eddy, Mau-Thek; Triedman, John K.; Walsh, Edward P.; McGowan, Francis X.; del Nido, Pedro J.; Cowan, Douglas B.

    2006-01-01

    In children, interruption of cardiac atrioventricular (AV) electrical conduction can result from congenital defects, surgical interventions, and maternal autoimmune diseases during pregnancy. Complete AV conduction block is typically treated by implanting an electronic pacemaker device, although long-term pacing therapy in pediatric patients has significant complications. As a first step toward developing a substitute treatment, we implanted engineered tissue constructs in rat hearts to create an alternative AV conduction pathway. We found that skeletal muscle-derived cells in the constructs exhibited sustained electrical coupling through persistent expression and function of gap junction proteins. Using fluorescence in situ hybridization and polymerase chain reaction analyses, myogenic cells in the constructs were shown to survive in the AV groove of implanted hearts for the duration of the animal’s natural life. Perfusion of hearts with fluorescently labeled lectin demonstrated that implanted tissues became vascularized and immunostaining verified the presence of proteins important in electromechanical integration of myogenic cells with surrounding recipient rat cardiomyocytes. Finally, using optical mapping and electrophysiological analyses, we provide evidence of permanent AV conduction through the implant in one-third of recipient animals. Our experiments provide a proof-of-principle that engineered tissue constructs can function as an electrical conduit and, ultimately, may offer a substitute treatment to conventional pacing therapy. PMID:16816362

  17. An overview of Korean astronaut’s space experiments

    NASA Astrophysics Data System (ADS)

    Lee, J. H.; Kim, Y. K.; Yi, S. Y.; Kim, K. S.; Kang, S. W.; Choi, G. H.; Sim, E. S.

    2010-10-01

    The paper presents an overview of the scientific space experiments in the Korean Astronaut Program (KAP) that were conducted on the International Space Station (ISS), beginning with launch of the Soyuz TMA-12 spacecraft with the first Korean astronaut and two Russian astronauts on April 8, 2008 and returning to Earth on April 19, 2008. During the 10 days aboard the ISS, the Korean astronaut successfully completed thirteen scientific experiments in biology, life science, material science, earth science, and system engineering, five educational space experiments, and three kinds of international collaboration experiments. These experiments were the first Korean manned space experiments and these missions were the first steps toward the manned space exploration by Korea. In this paper, we briefly discuss the descriptions, conduct, and results of the space experiments and discuss future plans. In addition, the lessons learned with respect to the performing of these manned space experiments on the ISS are presented.

  18. Synthesis and characterization of soluble conducting polymers and conducting adhesives

    NASA Astrophysics Data System (ADS)

    Oztemiz, Serhan

    setting feature of the cyanoacrylates, a fast and serviceable conducting adhesive is formulated. Environmentally stable and electrically conducting cyanoacrylate formulations have been successfully prepared by introducing silver particles into a stabilized cyanoacrylate formulation. Silver particles have been observed to increase the viscosity and decrease the thixotropicity of the formulations. The stability of the formulations was achieved by using excess amounts of anionic stabilizers. This excess amount of inhibitor increases the set time by delaying the start of the reaction. This inhibition problem was solved by introducing functional amine groups and accelerating the reaction. Addition of the amine groups created more nucleation sites on the surface, which competed with the stabilizer to start the reaction. The use of accelerators did not affect the adhesive strength of the bond, however, it did change the resistivity of the adhesive joint.

  19. Thermal conductivity of bulk nanostructured lead telluride

    SciTech Connect

    Hori, Takuma; Chen, Gang; Shiomi, Junichiro

    2014-01-13

    Thermal conductivity of lead telluride with embedded nanoinclusions was studied using Monte Carlo simulations with intrinsic phonon transport properties obtained from first-principles-based lattice dynamics. The nanoinclusion/matrix interfaces were set to completely reflect phonons to model the maximum interface-phonon-scattering scenario. The simulations with the geometrical cross section and volume fraction of the nanoinclusions matched to those of the experiment show that the experiment has already reached the theoretical limit of thermal conductivity. The frequency-dependent analysis further identifies that the thermal conductivity reduction is dominantly attributed to scattering of low frequency phonons and demonstrates mutual adaptability of nanostructuring and local disordering.

  20. Cardiac conduction system

    MedlinePlus Videos and Cool Tools

    ... signals to the heart muscle causing it to contract. The main components of the cardiac conduction system ... the sequence by causing the atrial muscles to contract. From there, the signal travels to the AV ...