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Sample records for acs atmosphere revitalization

  1. Modeling of Atmosphere Revitalization

    NASA Technical Reports Server (NTRS)

    Coker, Robert; Knox, James; Kittredge, Kenneth

    2012-01-01

    NASA's AES is pioneering new approaches for future human missions beyond Earth orbit. All spacecraft systems must be minimized with respect to mass, power, and volume. Here, we show work related to improving system efficiency and reliability for water separation systems on crewed vehicles and the initial development of COMSOL simulations in support of the Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project

  2. Developments in Atmosphere Revitalization Modeling and Simulation

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Kittredge, Kenneth; Xoker, Robert F.; Cummings, Ramona; Gomez, Carlos F.

    2012-01-01

    "NASA's Advanced Exploration Systems (AES) program is pioneering new approaches for rapidly developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond Earth orbit" (NASA 2012). These forays beyond the confines of earth's gravity will place unprecedented demands on launch systems. They must not only blast out of earth's gravity well as during the Apollo moon missions, but also launch the supplies needed to sustain a crew over longer periods for exploration missions beyond earth's moon. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. Current efforts are focused on improving the current state-of-the-art systems utilizing fixed beds of sorbent pellets by evaluating structured sorbents, seeking more robust pelletized sorbents, and examining alternate bed configurations to improve system efficiency and reliability. These development efforts combine testing of sub-scale systems and multi-physics computer simulations to evaluate candidate approaches, select the best performing options, and optimize the configuration of the selected approach, which is then implemented in a full-scale integrated atmosphere revitalization test. This paper describes the development of atmosphere revitalization models and simulations. A companion paper discusses the hardware design and sorbent screening and characterization effort in support of the Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project within the AES program.

  3. Modeling of Revitalization of Atmospheric Water

    NASA Technical Reports Server (NTRS)

    Coker, Robert; Knox, Jim

    2014-01-01

    The Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project was initiated in September of 2011 as part of the Advanced Exploration Systems (AES) program. Under the ARREM project, testing of sub-scale and full-scale systems has been combined with multiphysics computer simulations for evaluation and optimization of subsystem approaches. In particular, this paper describes the testing and modeling of the water desiccant subsystem of the carbon dioxide removal assembly (CDRA). The goal is a full system predictive model of CDRA to guide system optimization and development.

  4. The shuttle orbiter cabin atmospheric revitalization systems

    NASA Technical Reports Server (NTRS)

    Ward, C. F.; Owens, W. L.

    1975-01-01

    The Orbiter Atmospheric Revitalization Subsystem (ARS) and Pressure Control Subsystem (ARPCS) are designed to provide the flight crew and passengers with a pressurized environment that is both life-supporting and within crew comfort limitations. The ARPCS is a two-gas (oxygen-nitrogen) system that obtains oxygen from the Power Reactant Supply and Distribution (PRSD) subsystem and nitrogen from the nitrogen storage tanks. The ARS includes the water coolant loop; cabin CO2, odor, humidity and temperature control; and avionics cooling. Baseline ARPCS and ARS changes since 1973 include removal of the sublimator from the water coolant loop, an increase in flowrates to accommodate increased loads, elimination of the avionics bay isolation from the cabin, a decision to have an inert vehicle during ferry flight, elimination of coldwall tubing around windows and hatches, and deletion of the cabin heater.

  5. International Space Station Atmosphere Control and Supply, Atmosphere Revitalization, and Water Recovery and Management Subsystem - Verification for Node 1

    NASA Technical Reports Server (NTRS)

    Williams, David E.

    2007-01-01

    The International Space Station (ISS) Node 1 Environmental Control and Life Support (ECLS) System is comprised of five subsystems: Atmosphere Control and Supply (ACS), Atmosphere Revitalization (AR), Fire Detection and Suppression (FDS), Temperature and Humidity Control (THC), and Water Recovery and Management (WRM). This paper provides a summary of the nominal operation of the Node 1 ACS, AR, and WRM design and detailed Element Verification methodologies utilized during the Qualification phase for Node 1.

  6. Nanoporous Materials in Atmosphere Revitalization. Chapter 1

    NASA Technical Reports Server (NTRS)

    Hernandez-Maldonado, J.; Ishikawa, Yasuyuki; Luna, Bernadette; Junaedi, Christian; Mulloth, Lila; Perry, Jay L.; Raptis, Raphael G.; Roychoudhury, Subir

    2012-01-01

    Atmospheric Revitalization (AR) is the term the National Aeronautics and Space Administration (NASA) uses to encompass the engineered systems that maintain a safe, breathable gaseous atmosphere inside a habitable space cabin. An AR subsystem is a key part of the Environmental Control and Life Support (ECLS) system for habitable space cabins. The ultimate goal for AR subsystem designers is to 'close the loop', that is, to capture gaseous human metabolic products, specifically water vapor (H2O) and Carbon dioxide (CO2), for maximal Oxygen (o2) recovery and to make other useful resources from these products. The AR subsystem also removes trace chemical contaminants from the cabin atmosphere to preserve cabin atmospheric quality, provides O2 and may include instrumentation to monitor cabin atmospheric quality. Long duration crewed space exploration missions require advancements in AR process technologies in order to reduce power consumption and mass and to increase reliability compared to those used for shorter duration missions that are typically limited to Low Earth Orbit. For example, current AR subsystems include separate processors and process air flow loops for removing metabolic CO2 and volatile organic tract contaminants (TCs). Physical adsorbents contained in fixed, packed beds are employed in these processors. Still, isolated pockets of high carbon dioxide have been suggested as a trigger for crew headaches and concern persists about future cabin ammonia (NH3) levels as compared with historical flights. Developers are already focused on certain potential advancements. ECLS systems engineers envision improving the AR subsystem by combining the functions of TC control and CO2 removal into a single regenerable process and moving toward structured sorbents - monoliths - instead of granular material. Monoliths present a lower pressure drop and eliminate particle attrition problems that result from bed containment. New materials and configurations offer promise for

  7. Simulation Helps Improve Atmosphere Revitalization Systems for Manned Spacecraft

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Coker, RObert

    2014-01-01

    Life support systems for manned spacecraft must provide breathable air and drinkable water for the astronauts. Through the Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project, engineers at NASA are developing atmosphere control devices for the safety of the onboard crew. The atmosphere in a manned spacecraft needs to be regularly revitalized in order to ensure the safety of the astronauts and the success of the space mission. For missions lasting a few months, this means air is continuously dehumidified, water collected for re-use, and carbon dioxide (CO2) ejected. One component of the onboard atmosphere control system is a water-saving device that Jim Knox, aerospace engineer at NASA, is optimizing through the Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project. He is leading a team at the Marshall Space Flight Center (Huntsville, Alabama) that is aiming to make the assembly more cost-effective and efficient by reducing its power usage and maximizing the water saved; their goal is to save 80-90% of the water in the air. They hope to offer flight system developers at NASA an integrated approach to atmosphere revitalization and water collection that will ultimately increase the time and distance space missions can travel.

  8. Trade Spaces in Crewed Spacecraft Atmosphere Revitalization System Development

    NASA Technical Reports Server (NTRS)

    Perry, Jay L.; Bagdigian, Robert M.; Carrasquillo, Robyn L.

    2010-01-01

    Developing the technological response to realizing an efficient atmosphere revitalization system for future crewed spacecraft and space habitats requires identifying and describing functional trade spaces. Mission concepts and requirements dictate the necessary functions; however, the combination and sequence of those functions possess significant flexibility. Us-ing a closed loop environmental control and life support (ECLS) system architecture as a starting basis, a functional unit operations approach is developed to identify trade spaces. Generalized technological responses to each trade space are discussed. Key performance parameters that apply to functional areas are described.

  9. Challenges in the development of the orbiter atmosphere revitalization subsystem

    NASA Technical Reports Server (NTRS)

    Prince, R. N.; Swider, J.; Wojnarowski, J.; Decrisantis, A.; Ord, G. R.; Walleshauser, J. J.; Gibb, J. W.

    1985-01-01

    The space shuttle orbiter atmospheric revitalization subsystem provides thermal and contaminant control as well as total- and oxygen partial-pressure control of the environment within the orbiter crew cabin. Challenges that occurred during the development of this subsystem for the space shuttle orbiter are described. The design of the rotating hardware elements of the system (pumps, fans, etc.) required significant development to meet the requirements of long service life, maintainability, and high cycle-fatigue life. As a result, a stringent development program, particularly in the areas of bearing life and heat dissipation, was required. Another area requiring significant development was cabin humidity control and condensate collection.

  10. Additional Developments in Atmosphere Revitalization Modeling and Simulation

    NASA Technical Reports Server (NTRS)

    Coker, Robert F.; Knox, James C.; Cummings, Ramona; Brooks, Thomas; Schunk, Richard G.; Gomez, Carlos

    2013-01-01

    NASA's Advanced Exploration Systems (AES) program is developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond Earth orbit. These forays beyond the confines of earth's gravity will place unprecedented demands on launch systems. They must launch the supplies needed to sustain a crew over longer periods for exploration missions beyond earth's moon. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. Current efforts are focused on improving the current state-of-the-art systems utilizing fixed beds of sorbent pellets by evaluating structured sorbents, seeking more robust pelletized sorbents, and examining alternate bed configurations to improve system efficiency and reliability. These development efforts combine testing of sub-scale systems and multi-physics computer simulations to evaluate candidate approaches, select the best performing options, and optimize the configuration of the selected approach. This paper describes the continuing development of atmosphere revitalization models and simulations in support of the Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project within the AES program.

  11. Additional Developments in Atmosphere Revitalization Modeling and Simulation

    NASA Technical Reports Server (NTRS)

    Coker, Robert F.; Knox, James C.; Cummings, Ramona; Brooks, Thomas; Schunk, Richard G.

    2013-01-01

    NASA's Advanced Exploration Systems (AES) program is developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond Earth orbit. These forays beyond the confines of earth's gravity will place unprecedented demands on launch systems. They must launch the supplies needed to sustain a crew over longer periods for exploration missions beyond earth's moon. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. Current efforts are focused on improving the current state-of-the-art systems utilizing fixed beds of sorbent pellets by evaluating structured sorbents, seeking more robust pelletized sorbents, and examining alternate bed configurations to improve system efficiency and reliability. These development efforts combine testing of sub-scale systems and multi-physics computer simulations to evaluate candidate approaches, select the best performing options, and optimize the configuration of the selected approach. This paper describes the continuing development of atmosphere revitalization models and simulations in support of the Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM)

  12. Atmosphere Revitalization Technology Development for Crewed Space Exploration

    NASA Technical Reports Server (NTRS)

    Perry, Jay L.; Carrasquillo, Robyn L.; Harris, Danny W.

    2006-01-01

    As space exploration objectives extend human presence beyond low Earth orbit, the solutions to technological challenges presented by supporting human life in the hostile space environment must build upon experience gained during past and present crewed space exploration programs. These programs and the cabin atmosphere revitalization process technologies and systems developed for them represent the National Aeronautics and Space Administration s (NASA) past and present operational knowledge base for maintaining a safe, comfortable environment for the crew. The contributions of these programs to the NASA s technological and operational working knowledge base as well as key strengths and weaknesses to be overcome are discussed. Areas for technological development to address challenges inherent with the Vision for Space Exploration (VSE) are presented and a plan for their development employing unit operations principles is summarized

  13. Space Suit Environment Testing of the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Lin, Amy; Sweterlitsch, Jeffrey; Cox, Marlon

    2009-01-01

    An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). In two previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of this technology in a sea-level pressure environment with simulated human metabolic loads. Another paper at this year s conference discusses similar testing with real human metabolic loads, including some closed-loop testing with emergency breathing masks. The Orion ARS is designed to also support extravehicular activity operations from a depressurized cabin. The next step in developmental testing at JSC was, therefore, to test this ARS technology in a typical closed space suit loop environment with low-pressure pure oxygen inside the process loop and vacuum outside the loop. This was the first instance of low-pressure oxygen loop testing of a new Orion ARS technology, and was conducted with simulated human metabolic loads in December 2008. The test investigated pressure drops through two different styles of prototype suit umbilical connectors and general swing-bed performance with both umbilical configurations as well as with a short jumper line installed in place of the umbilicals. Other interesting results include observations on the thermal effects of swing-bed operation in a vacuum environment and a recommendation of cycle time to maintain acceptable atmospheric CO2 and moisture levels.

  14. Space Suit Environment Testing of the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Button, Amy B.; Sweterlitsch, Jeffrey J.; Cox, Marlon R.

    2010-01-01

    An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). In three previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of this technology. That testing was performed in a sea-level pressure environment with both simulated and real human metabolic loads, and in both open and closed-loop configurations. The Orion ARS is designed to also support space-suited operations in a depressurized cabin, so the next step in developmental testing at JSC was to test the ARS technology in a typical closed space suit-loop environment with low-pressure oxygen inside the process loop and vacuum outside the loop. This was the first instance of low-pressure, high-oxygen, closed-loop testing of the Orion ARS technology, and it was conducted with simulated human metabolic loads in March 2009. The test investigated pressure drops and flow balancing through two different styles of prototype suit umbilical connectors. General swing-bed performance was tested with both umbilical configurations, as well as with a short jumper line installed in place of the umbilicals. Other interesting results include observations on the thermal effects of swing-bed operation in a vacuum environment and a recommendation of cycle time to maintain acceptable suit atmospheric CO2 and moisture levels.

  15. Trace Contaminant Testing with the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Button, Amy B.; Sweterlitsch, Jeffrey J.; Broerman, Craig D.; Campbell, Melissa L.

    2010-01-01

    Every spacecraft atmosphere contains trace contaminants resulting from offgassing by cabin materials and human passengers. An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). Part of the risk mitigation effort for this new technology is the study of how atmospheric trace contaminants will affect and be affected by the technology. One particular area of concern is ammonia, which, in addition to the normal spacecraft sources, can also be offgassed by the amine-based sorbent. In the spring of 2009, tests were performed at Johnson Space Center (JSC) with typical cabin atmosphere levels of five of the most common trace gases, most of which had not yet been tested with this technology. A subscale sample of the sorbent was exposed to each of the chemicals mixed into a stream of moist, CO2-laden air, and the CO2 adsorption capacity of the sorbent was compared before and after the exposure. After these typical-concentration chemicals were proven to have negligible effect on the subscale sample, tests proceeded on a full-scale test article in a sealed chamber with a suite of eleven contaminants. To isolate the effects of various test rig components, several extended-duration tests were run: without injection or scrubbing, with injection and without scrubbing, with injection of both contaminants and metabolic CO2 and water vapor loads and scrubbing by both the test article and dedicated trace contaminant filters, and with the same injections and scrubbing by only the test article. The high-level results of both the subscale and full-scale tests are examined in this paper.

  16. First Human Testing of the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Lin, Amy; Sweterlitsch, Jeffrey

    2008-01-01

    An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). In two previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of the technology in a representative environment with simulated human metabolic loads. The next step in developmental testing at JSC was to replace the simulated humans with real humans; this testing was conducted in the spring of 2008. This first instance of human testing of a new Orion ARS technology included several cases in a sealed Orione-quivalent free volume and three cases using emergency breathing masks connected directly to the ARS loop. Significant test results presented in this paper include comparisons between the standard metabolic rates for CO2 and water vapor production published in Orion requirements documents and real-world rate ranges observed with human test subjects. Also included are qualitative assessments of process flow rate and closed-loop pressure-cycling tolerability while using the emergency masks. Recommendations for modifications to the Orion ARS design and operation, based on the test results, conclude the paper.

  17. Reduced Pressure Cabin Testing of the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Button, Amy; Sweterlisch, Jeffery J.

    2013-01-01

    An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Atmosphere Revitalization System for moderate duration missions of the Orion Multipurpose Crew Vehicle. In previous years at this conference, reports were presented on extensive Johnson Space Center testing of this technology in a sea-level pressure environment with simulated and actual human metabolic loads in both open and closed-loop configurations. In 2011, the technology was tested in an open cabin-loop configuration at ambient and two sub-ambient pressures to compare the performance of the system to the results of previous tests at ambient pressure. The testing used a human metabolic simulator with a different type of water vapor generation than previously used, which added some unique challenges in the data analysis. This paper summarizes the results of: baseline and some matrix testing at all three cabin pressures, increased vacuum regeneration line pressure with a high metabolic load, a set of tests studying CO2 and water vapor co-adsorption effects relative to model-predicted performance, and validation tests of flight program computer model predictions with specific operating conditions.

  18. 2009 Continued Testing of the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Button, Amy B.; Swerterlitsch, Jeffrey J.

    2010-01-01

    An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). In three previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of this technology in a sea-level pressure environment, with simulated and real human metabolic loads, in both open and closed-loop configurations. The test article design was iterated a third time before the latest series of such tests, which was performed in the first half of 2009. The new design incorporates a canister configuration modification for overall unit compactness and reduced pressure drop, as well as a new process flow control valve that incorporates both compressed gas purge and dual-end vacuum desorption capabilities. This newest test article is very similar to the flight article designs. Baseline tests of the new unit were performed to compare its performance to that of the previous test articles. Testing of compressed gas purge operations helped refine launchpad operating condition recommendations developed in earlier testing. Operating conditions used in flight program computer models were tested to validate the model projections. Specific operating conditions that were recommended by the JSC test team based on past test results were also tested for validation. The effects of vacuum regeneration line pressure on resulting cabin conditions was studied for high metabolic load periods, and a maximum pressure is recommended

  19. First Human Testing of the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Lin, Amy; Sweterlitsch, Jeffrey

    2009-01-01

    An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). In two previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of the technology in a representative environment with simulated human metabolic loads. The next step in developmental testing at JSC was to replace the simulated humans with real humans; this testing was conducted in the spring of 2008. This first instance of human testing of a new Orion ARS technology included several cases in a sealed Orion-equivalent free volume and three cases using emergency breathing masks connected directly to the ARS loop. Significant test results presented in this paper include comparisons between the standard metabolic rates for CO2 and water vapor production published in Orion requirements documents and real-world rate ranges observed with human test subjects. Also included are qualitative assessments of process flow rate and closed-loop pressure-cycling tolerability while using the emergency masks. Recommendations for modifications to the Orion ARS design and operation, based on the test results, conclude the paper.

  20. Reduced Pressure Cabin Testing of the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Button, Amy B.; Sweterlitsch, Jeffrey J.

    2013-01-01

    An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by United Technologies Corp. Aerospace Systems (UTAS, formerly Hamilton Sundstrand) and baselined for the Atmosphere Revitalization System for moderate duration missions of the Orion Multipurpose Crew Vehicle (MPCV). In previous years at this conference, reports were presented on extensive Johnson Space Center testing of this technology in a sea-level pressure environment with simulated and actual human metabolic loads in both open and closed-loop configurations. In 2011, the technology was tested in an open cabin-loop configuration at ambient and two sub-ambient pressures to compare the performance of the system to the results of previous tests at ambient pressure. The testing used a human metabolic simulator with a different type of water vapor generation than previously used, which added some unique challenges in the data analysis. This paper summarizes the results of: baseline and some matrix testing at all three cabin pressures, increased vacuum regeneration line pressure testing with a high metabolic load, a set of tests studying CO2 and water vapor co-adsorption effects relative to model-predicted performance, and validation tests of flight project computer model predictions with specific operating conditions.

  1. Design, Development, Test, and Evaluation of Atmosphere Revitalization and Environmental Monitoring Systems for Long Duration Missions

    NASA Technical Reports Server (NTRS)

    Roman, Monsi C.; Perry, Jay L.; Jan, Darrell L.

    2012-01-01

    The Advanced Exploration Systems Program's Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project is working to mature optimum atmosphere revitalization and environmental monitoring system architectures. It is the project's objective to enable exploration beyond Lower Earth Orbit (LEO) and improve affordability by focusing on three primary goals: 1) achieving high reliability, 2) reducing dependence on a ground-based logistics resupply model, and 3) maximizing commonality between atmosphere revitalization subsystem components and those needed to support other exploration elements. The ARREM project's strengths include using existing developmental hardware and testing facilities, when possible, and and a well-coordinated effort among the NASA field centers that contributed to past ARS and EMS technology development projects.

  2. Functional Performance of an Enabling Atmosphere Revitalization Subsystem Architecture for Deep Space Exploration Missions

    NASA Technical Reports Server (NTRS)

    Perry, Jay L.; Abney, Morgan B.; Frederick, Kenneth R.; Greenwood, Zachary W.; Kayatin, Matthew J.; Newton, Robert L.; Parrish, Keith J.; Roman, Monsi C.; Takada, Kevin C.; Miller, Lee A.; Scott, Joseph P.; Stanley, Christine M.

    2013-01-01

    A subsystem architecture derived from the International Space Station's (ISS) Atmosphere Revitalization Subsystem (ARS) has been functionally demonstrated. This ISS-derived architecture features re-arranged unit operations for trace contaminant control and carbon dioxide removal functions, a methane purification component as a precursor to enhance resource recovery over ISS capability, operational modifications to a water electrolysis-based oxygen generation assembly, and an alternative major atmospheric constituent monitoring concept. Results from this functional demonstration are summarized and compared to the performance observed during ground-based testing conducted on an ISS-like subsystem architecture. Considerations for further subsystem architecture and process technology development are discussed.

  3. Development and Testing of a Sorbent-Based Atmosphere Revitalization System 2010/2011

    NASA Technical Reports Server (NTRS)

    Miller, Lee A.; Knox, James C.

    2012-01-01

    Spacecraft being developed for future exploration missions incorporate Environmental Control and Life Support Systems (ECLSS) that limit weight, power, and volume thus requiring systems with higher levels of efficiency while maintaining high dependability and robustness. For air revitalization, an approach that meets those goals utilizes a regenerative Vacuum-Swing Adsorption (VSA) system that removes 100% of the CO2 from the cabin atmosphere as well as 100% of the water. A Sorbent Based Atmosphere Revitalization (SBAR) system is a VSA system that utilizes standard commercial adsorbents that have been proven effective and safe in spacecraft including Skylab and the International Space Station. The SBAR system is the subject of a development, test, and evaluation program that is being conducted at NASA s Marshall Space Flight Center. While previous testing had validated that the technology is a viable option, potential improvements to system design and operation were identified. Modifications of the full-scale SBAR test articles and adsorption cycles have been implemented and have shown significant performance gains resulting in a decrease in the consumables required for a mission as well as improved mission safety. Previous testing had utilized single bed test articles, during this period the test facility was enhanced to allow testing on the full 2-bed SBAR system. The test facility simulates a spacecraft ECLSS and allows testing of the SBAR system over the full range of operational conditions using mission simulations that assess the real-time performance of the SBAR system during scenarios that include the metabolic transients associated with extravehicular activity. Although future manned missions are currently being redefined, the atmosphere revitalization requirements for the spacecraft are expected to be quite similar to the Orion and the Altair vehicles and the SBAR test program addressed validation to the defined mission requirements as well as operation

  4. Finding Atmospheric Composition (AC) Metadata

    NASA Technical Reports Server (NTRS)

    Strub, Richard F..; Falke, Stefan; Fiakowski, Ed; Kempler, Steve; Lynnes, Chris; Goussev, Oleg

    2015-01-01

    The Atmospheric Composition Portal (ACP) is an aggregator and curator of information related to remotely sensed atmospheric composition data and analysis. It uses existing tools and technologies and, where needed, enhances those capabilities to provide interoperable access, tools, and contextual guidance for scientists and value-adding organizations using remotely sensed atmospheric composition data. The initial focus is on Essential Climate Variables identified by the Global Climate Observing System CH4, CO, CO2, NO2, O3, SO2 and aerosols. This poster addresses our efforts in building the ACP Data Table, an interface to help discover and understand remotely sensed data that are related to atmospheric composition science and applications. We harvested GCMD, CWIC, GEOSS metadata catalogs using machine to machine technologies - OpenSearch, Web Services. We also manually investigated the plethora of CEOS data providers portals and other catalogs where that data might be aggregated. This poster is our experience of the excellence, variety, and challenges we encountered.Conclusions:1.The significant benefits that the major catalogs provide are their machine to machine tools like OpenSearch and Web Services rather than any GUI usability improvements due to the large amount of data in their catalog.2.There is a trend at the large catalogs towards simulating small data provider portals through advanced services. 3.Populating metadata catalogs using ISO19115 is too complex for users to do in a consistent way, difficult to parse visually or with XML libraries, and too complex for Java XML binders like CASTOR.4.The ability to search for Ids first and then for data (GCMD and ECHO) is better for machine to machine operations rather than the timeouts experienced when returning the entire metadata entry at once. 5.Metadata harvest and export activities between the major catalogs has led to a significant amount of duplication. (This is currently being addressed) 6.Most (if not all

  5. CO2 Removal and Atmosphere Revitalization Systems for Next Generation Space Flight

    NASA Technical Reports Server (NTRS)

    Luna, Bernadette; Mulloth, Lila M.; Varghese, Mini M.; Hogan, John Andrew

    2010-01-01

    Removal of metabolic CO2 from breathing air is a vital process for life support in all crewed space missions. A CO2 removal processor called the Low Power CO2 Removal (LPCOR) system is being developed in the Bioengineering Branch at NASA Ames Research Center. LPCOR utilizes advanced adsorption and membrane gas separation processes to achieve substantial power and mass reduction when compared to the state-of-the-art carbon dioxide removal assembly (CORA) of the US segment of the International Space Station (ISS). LPCOR is an attractive alternative for use in commercial spacecraft for short-duration missions and can easily be adapted for closed-loop life support applications. NASA envisions a next-generation closed-loop atmosphere revitalization system that integrates advanced CO2 removal, O2 recovery, and trace contaminant control processes to improve overall system efficiency. LPCOR will serve as the front end to such a system. LPCOR is a reliable air revitalization technology that can serve both the near-term and long-term human space flight needs of NASA and its commercial partners.

  6. Independent Orbiter Assessment (IOA): Assessment of the atmospheric revitalization pressure control subsystem FMEA/CIL

    NASA Technical Reports Server (NTRS)

    Saiidi, M. J.

    1988-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the atmospheric Revitalization Pressure Control Subsystem (ARPCS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL proposed Post 51-L updates based upon the CCB/PRCB presentations and an informal criticality summary listing. A discussion of each discrepancy from the comparison is provided through additional analysis as required. These discrepancies were flagged as issues, and recommendations were made based on the FMEA data available at the time. This report documents the results of that comparison for the Orbiter ARPCS hardware.

  7. Evaluation of an Atmosphere Revitalization Subsystem for Deep Space Exploration Missions

    NASA Technical Reports Server (NTRS)

    Perry, Jay L.; Abney, Morgan B.; Conrad, Ruth E.; Frederick, Kenneth R.; Greenwood, Zachary W.; Kayatin, Matthew J.; Knox, James C.; Newton, Robert L.; Parrish, Keith J.; Takada, Kevin C.; Miller, Lee A.; Scott, Joseph P.; Stanley, Christine M.

    2015-01-01

    An Atmosphere Revitalization Subsystem (ARS) suitable for deployment aboard deep space exploration mission vehicles has been developed and functionally demonstrated. This modified ARS process design architecture was derived from the International Space Station's (ISS) basic ARS. Primary functions considered in the architecture include trace contaminant control, carbon dioxide removal, carbon dioxide reduction, and oxygen generation. Candidate environmental monitoring instruments were also evaluated. The process architecture rearranges unit operations and employs equipment operational changes to reduce mass, simplify, and improve the functional performance for trace contaminant control, carbon dioxide removal, and oxygen generation. Results from integrated functional demonstration are summarized and compared to the performance observed during previous testing conducted on an ISS-like subsystem architecture and a similarly evolved process architecture. Considerations for further subsystem architecture and process technology development are discussed.

  8. Independent Orbiter Assessment (IOA): Analysis of the atmospheric revitalization pressure control subsystem

    NASA Technical Reports Server (NTRS)

    Saiidi, M. J.; Duffy, R. E.; Mclaughlin, T. D.

    1986-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis/Critical Items List (FMEA/CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The independent analysis results corresponding to the Orbiter Atmospheric Revitalization and Pressure Control Subsystem (ARPCS) are documented. The ARPCS hardware was categorized into the following subdivisions: (1) Atmospheric Make-up and Control (including the Auxiliary Oxygen Assembly, Oxygen Assembly, and Nitrogen Assembly); and (2) Atmospheric Vent and Control (including the Positive Relief Vent Assembly, Negative Relief Vent Assembly, and Cabin Vent Assembly). The IOA analysis process utilized available ARPCS hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.

  9. International Space Station Program Phase 3 Integrated Atmosphere Revitalization Subsystem Test

    NASA Technical Reports Server (NTRS)

    Perry, J. L.; Franks, G. D.; Knox, J. C.

    1997-01-01

    Testing of the International Space Station (ISS) U.S. Segment baseline configuration of the Atmosphere Revitalization Subsystem (ARS) by NASA's Marshall Space Flight Center (MSFC) was conducted as part of the Environmental Control and Life Support System (ECLSS) design and development program. This testing was designed to answer specific questions regarding the control and performance of the baseline ARS subassemblies in the ISS U.S. Segment configuration. These questions resulted from the continued maturation of the ISS ECLSS configuration and design requirement changes since 1992. The test used pressurized oxygen injection, a mass spectrometric major constituent analyzer, a Four-Bed Molecular Sieve Carbon Dioxide Removal Assembly, and a Trace Contaminant Control Subassembly to maintain the atmospheric composition in a sealed chamber at ISS specifications for 30 days. Human metabolic processes for a crew of four were simulated according to projected ISS mission time lines. The performance of a static feed water electrolysis Oxygen Generator Assembly was investigated during the test preparation phases; however, technical difficulties prevented its use during the integrated test. The Integrated ARS Test (IART) program built upon previous closed-door and open-door integrated testing conducted at MSFC between 1987 and 1992. It is the most advanced test of an integrated ARS conducted by NASA to demonstrate its end-to-end control and overall performance. IART test objectives, facility design, pretest analyses, test and control requirements, and test results are presented.

  10. Carbon dioxide removal system for closed loop atmosphere revitalization, candidate sorbents screening and test results

    NASA Astrophysics Data System (ADS)

    Mattox, E. M.; Knox, J. C.; Bardot, D. M.

    2013-05-01

    Due to the difficulty and expense it costs to resupply manned-spacecraft habitats, a goal is to create a closed loop atmosphere revitalization system, in which precious commodities such as oxygen, carbon dioxide, and water are continuously recycled. Our aim is to test other sorbents for their capacity for future spacecraft missions, such as on the Orion spacecraft, or possibly lunar or Mars mission habitats to see if they would be better than the zeolite sorbents on the 4-bed molecular sieve. Some of the materials being tested are currently used for other industry applications. Studying these sorbents for their specific spacecraft application is different from that for applications on earth because in space, there are certain power, mass, and volume limitations that are not as critical on Earth. In manned-spaceflight missions, the sorbents are exposed to a much lower volume fraction of CO2 (0.6% volume CO2) than on Earth. LiLSX was tested for its CO2 capacity in an atmosphere like that of the ISS. Breakthrough tests were run to establish the capacities of these materials at a partial pressure of CO2 that is seen on the ISS. This paper discusses experimental results from benchmark materials, such as results previously obtained from tests on Grade 522, and the forementioned candidate materials for the Carbon Dioxide Removal Assembly (CDRA) system.

  11. Space shuttle atmospheric revitalization subsystem/active thermal control subsystem computer program (users manual)

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A shuttle (ARS) atmosphere revitalization subsystem active thermal control subsystem (ATCS) performance routine was developed. This computer program is adapted from the Shuttle EC/LSS Design Computer Program. The program was upgraded in three noteworthy areas: (1) The functional ARS/ATCS schematic has been revised to accurately synthesize the shuttle baseline system definition. (2) The program logic has been improved to provide a more accurate prediction of the integrated ARS/ATCS system performance. Additionally, the logic has been expanded to model all components and thermal loads in the ARS/ATCS system. (3) The program is designed to be used on the NASA JSC crew system division's programmable calculator system. As written the new computer routine has an average running time of five minutes. The use of desk top type calculation equipment, and the rapid response of the program provides the NASA with an analytical tool for trade studies to refine the system definition, and for test support of the RSECS or integrated Shuttle ARS/ATCS test programs.

  12. The Orion Atmosphere Revitalization Technology in Manned Ambient Pressure Space Suit Testing

    NASA Technical Reports Server (NTRS)

    Button, Amy; Sweterlitsch, Jeffrey

    2011-01-01

    An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Atmosphere Revitalization System (ARS) for moderate duration missions of the Orion Multipurpose Crew Vehicle. The Orion ARS is designed to support not only open-cabin operations, tests of which have been reported in previous years at this conference, but also closed space suit-loop operations. A previous low-pressure suit loop test was performed with a human metabolic simulator, and humans wearing emergency masks were tested in a closed-loop configuration before that. In late 2011, simple tests were performed in a suit-loop configuration with human test subjects in prototype space suits with prototype umbilicals at ambient and two slightly above-ambient pressures. Trace contaminant filters and a prototype blower were also incorporated into the test rig. This paper discusses the performance of the ARS technology in that 2011 test configuration.

  13. Design and Performance of the Sorbent-Based Atmosphere Revitalization System for Orion

    NASA Technical Reports Server (NTRS)

    Ritter, James A.; Reynolds, Steven P.; Ebner, Armin D.; Knox, James C.; LeVan, M. Douglas

    2007-01-01

    Validation and simulations of a real-time dynamic cabin model were conducted on the sorbent-based atmosphere revitalization system for Orion. The dynamic cabin model, which updates the concentration of H2O and CO2 every second during the simulation, was able to predict the steady state model values for H2O and CO2 for long periods of steady metabolic production for a 4-person crew. It also showed similar trends for the exercise periods, where there were quick changes in production rates. Once validated, the cabin model was used to determine the effects of feed flow rate, cabin volume and column volume. A higher feed flow rate reduced the cabin concentrations only slightly over the base case, a larger cabin volume was able to reduce the cabin concentrations even further, and the lower column volume led to much higher cabin concentrations. Finally, the cabin model was used to determine the effect of the amount of silica gel in the column. As the amount increased, the cabin concentration of H2O decreased, but the cabin concentration of CO2 increased.

  14. A Discussion of Oxygen Recovery Definitions and Key Performance Parameters for Closed-Loop Atmosphere Revitalization Life Support Technology Development

    NASA Technical Reports Server (NTRS)

    Abney, Morgan B.; Perry, Jay L.

    2016-01-01

    Over the last 55 years, NASA has evolved life support for crewed space exploration vehicles from simple resupply during Project Mercury to the complex and highly integrated system of systems aboard the International Space Station. As NASA targets exploration destinations farther from low Earth orbit and mission durations of 500 to 1000 days, life support systems must evolve to meet new requirements. In addition to having more robust, reliable, and maintainable hardware, limiting resupply becomes critical for managing mission logistics and cost. Supplying a crew with the basics of food, water, and oxygen become more challenging as the destination ventures further from Earth. Aboard ISS the Atmosphere Revitalization Subsystem (ARS) supplies the crew's oxygen demand by electrolyzing water. This approach makes water a primary logistics commodity that must be managed carefully. Chemical reduction of metabolic carbon dioxide (CO2) provides a method of recycling oxygen thereby reducing the net ARS water demand and therefore minimizing logistics needs. Multiple methods have been proposed to achieve this recovery and have been reported in the literature. However, depending on the architecture and the technology approach, "oxygen recovery" can be defined in various ways. This discontinuity makes it difficult to compare technologies directly. In an effort to clarify community discussions of Oxygen Recovery, we propose specific definitions and describe the methodology used to arrive at those definitions. Additionally, we discuss key performance parameters for Oxygen Recovery technology development including challenges with comparisons to state-of-the-art.

  15. Performance Testing of a Photocatalytic Oxidation Module for Spacecraft Cabin Atmosphere Revitalization

    NASA Technical Reports Server (NTRS)

    Perry, Jay L.; Abney, Morgan B.; Frederick, Kenneth R.; Scott, Joseph P.; Kaiser, Mark; Seminara, Gary; Bershitsky, Alex

    2011-01-01

    Photocatalytic oxidation (PCO) is a candidate process technology for use in high volumetric flow rate trace contaminant control applications in sealed environments. The targeted application for PCO as applied to crewed spacecraft life support system architectures is summarized. Technical challenges characteristic of PCO are considered. Performance testing of a breadboard PCO reactor design for mineralizing polar organic compounds in a spacecraft cabin atmosphere is described. Test results are analyzed and compared to results reported in the literature for comparable PCO reactor designs.

  16. Lightside Atmospheric Revitalization System

    NASA Technical Reports Server (NTRS)

    Colling, A. K.; Cushman, R. J.; Hultman, M. M.; Nason, J. R.

    1980-01-01

    The system was studied as a replacement to the present baseline LiOH system for extended duration shuttle missions. The system consists of three subsystems: a solid amine water desorbed regenerable carbon dioxide removal system, a water vapor electrolysis oxygen generating system, and a Sabatier reactor carbon dioxide reduction system. The system is designed for use on a solar powered shuttle vehicle. The majority of the system's power requirements are utilized on the Sun side of each orbit, when solar power is available.

  17. Revitalization of School Facilities.

    ERIC Educational Resources Information Center

    Coffey, Andrea Barlow

    This study analyzed current practices in the revitalization of school buildings and assimilates data that can be used by school administrators when deciding on revitalization issues. Data from nine revitalized schools since 1985 and a literature review of the elements for planning the revitalization of school facilities indicate that structural…

  18. Land Revitalization Basics

    EPA Pesticide Factsheets

    EPA created the Land Revitalization Initiative to promote cross-program coordination on land reuse and revitalization projects to ensure that contaminated property is appropriately put back into productive use.

  19. Development and Testing of a Sorbent-Based Atmosphere Revitalization System for the Crew Exploration Vehicle 2007/2008

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Howard, David; Miller, Lee

    2008-01-01

    The design of a Vacuum-Swing Adsorption (VSA) system to remove metabolic water and metabolic carbon dioxide from the Orion Crew Exploration Vehicle (CEV) atmosphere is presented. The approach for Orion is a VSA system that removes not only 100 percent of the metabolic CO2 from the atmosphere, but also 100% of the metabolic water as well, a technology approach that has not been used in previous spacecraft life support systems. The design and development of the Sorbent Based Atmosphere Regeneration (SBAR) system, including test articles, a facility test stand, and full-scale testing in late 2007 and early 2008 is discussed.

  20. Gateways Revitalization Strategy

    EPA Pesticide Factsheets

    Lancaster County, PA, created the Gateway plan to reconnect various areas of the community, revitalize the economic base, improve and build on infrastructure and public/private partnerships, and retain current residents.

  1. Mathematical Analysis of High-Temperature Co-electrolysis of CO2 and O2 Production in a Closed-Loop Atmosphere Revitalization System

    SciTech Connect

    Michael G. McKellar; Manohar S. Sohal; Lila Mulloth; Bernadette Luna; Morgan B. Abney

    2010-03-01

    NASA has been evaluating two closed-loop atmosphere revitalization architectures based on Sabatier and Bosch carbon dioxide, CO2, reduction technologies. The CO2 and steam, H2O, co-electrolysis process is another option that NASA has investigated. Utilizing recent advances in the fuel cell technology sector, the Idaho National Laboratory, INL, has developed a CO2 and H2O co-electrolysis process to produce oxygen and syngas (carbon monoxide, CO and hydrogen, H2 mixture) for terrestrial (energy production) application. The technology is a combined process that involves steam electrolysis, CO2 electrolysis, and the reverse water gas shift (RWGS) reaction. A number of process models have been developed and analyzed to determine the theoretical power required to recover oxygen, O2, in each case. These models include the current Sabatier and Bosch technologies and combinations of those processes with high-temperature co-electrolysis. The cases of constant CO2 supply and constant O2 production were evaluated. In addition, a process model of the hydrogenation process with co-electrolysis was developed and compared. Sabatier processes require the least amount of energy input per kg of oxygen produced. If co-electrolysis replaces solid polymer electrolyte (SPE) electrolysis within the Sabatier architecture, the power requirement is reduced by over 10%, but only if heat recuperation is used. Sabatier processes, however, require external water to achieve the lower power results. Under conditions of constant incoming carbon dioxide flow, the Sabatier architectures require more power than the other architectures. The Bosch, Boudouard with co-electrolysis, and the hydrogenation with co-electrolysis processes require little or no external water. The Bosch and hydrogenation processes produce water within their reactors, which aids in reducing the power requirement for electrolysis. The Boudouard with co-electrolysis process has a higher electrolysis power requirement because carbon

  2. ACS experiment for atmospheric studies on "ExoMars-2016" Orbiter

    NASA Astrophysics Data System (ADS)

    Korablev, O. I.; Montmessin, F.; Fedorova, A. A.; Ignatiev, N. I.; Shakun, A. V.; Trokhimovskiy, A. V.; Grigoriev, A. V.; Anufreichik, K. A.; Kozlova, T. O.

    2015-12-01

    ACS is a set of spectrometers for atmospheric studies (Atmospheric Chemistry Suite). It is one of the Russian instruments for the Trace Gas Orbiter (TGO) of the Russian-European "ExoMars" program. The purpose of the experiment is to study the Martian atmosphere by means of two observations regimes: sensitive trace gases measurements in solar occultations and by monitoring the atmospheric state during nadir observations. The experiment will allow us to approach global problems of Mars research such as current volcanism, and the modern climate status and its evolution. Also, the experiment is intended to solve the mystery of methane presence in the Martian atmosphere. Spectrometers of the ACS set cover the spectral range from the near IR-range (0.7 μm) to the thermal IR-range (17 μm) with spectral resolution λ/Δλ reaching 50000. The ACS instrument consists of three independent IR spectrometers and an electronics module, all integrated in a single unit with common mechanical, electrical and thermal interfaces. The article gives an overview of scientific tasks and presents the concept of the experiment.

  3. The dynamic process of atmospheric water sorption in [EMIM][Ac] and mixtures of [EMIM][Ac] with biopolymers and CO2 capture in these systems.

    PubMed

    Chen, Yu; Sun, Xiaofu; Yan, Chuanyu; Cao, Yuanyuan; Mu, Tiancheng

    2014-10-02

    There are mainly three findings related to the dynamic process of atmospheric water sorption in the ionic liquid (IL) 1-ethyl-3-methlyl-imidazolium acetate ([EMIM][Ac]) and its mixtures with biopolymers (i.e., cellulose, chitin, and chitosan), and CO2 capture in these systems above. The analytical methods mainly include gravimetric hygroscopicity measurement and in situ infrared spectroscopy with the techniques of difference, derivative, deconvoluted attenuated total reflectance and two-dimensional correlation. These three findings are listed as below. (1) Pure [EMIM][Ac] only shows a two-regime pattern, while all the mixtures of [EMIM][Ac] with biopolymers (i.e., cellulose, chitin, and chitosan) present a three-regime tendency for the dynamic process of atmospheric water sorption. Specifically, the IL/chitosan mixture has a clear three-regime mode; the [EMIM][Ac]/chitin mixture has an unclear indiscernible regime 3; and the [EMIM][Ac]/cellulose mixture shows an indiscernible regime 2. (2) [EMIM][Ac] and its mixtures with biopolymers could physically absorb a trace amount of and chemically react with a much larger amount of CO2 from the air. The chemisorption capacity of CO2 in these pure and mixed systems is ordered as chitosan/[EMIM][Ac] mixture > chitin/[EMIM][Ac] mixture > cellulose/[EMIM][Ac] mixture > pure [EMIM][Ac] (ca. 0.09 mass ratio % g/g CO2/IL). (3) The CO2 solubility in [EMIM][Ac] decreases about 50% after being exposed to the atmospheric moist air for some specific time period.

  4. International Space Station Environmental Control and Life Support System Acceptance Testing for Node 1 Atmosphere Control and Supply Subsystem

    NASA Technical Reports Server (NTRS)

    Williams, David E.

    2009-01-01

    The International Space Station (ISS) Node 1 Environmental Control and Life Support (ECLS) System is comprised of five subsystems: Atmosphere Control and Supply (ACS), Atmosphere Revitalization (AR), Fire Detection and Suppression (FDS), Temperature and Humidity Control (THC), and Water Recovery and Management (WRM). This paper provides a summary of the Node 1 ECLS ACS subsystem design and a detailed discussion of the ISS ECLS Acceptance Testing methodology utilized for that subsystem.

  5. Designing Indigenous Language Revitalization

    ERIC Educational Resources Information Center

    Hermes, Mary; Bang, Megan; Marin, Ananda

    2012-01-01

    Endangered Indigenous languages have received little attention within the American educational research community. However, within Native American communities, language revitalization is pushing education beyond former iterations of culturally relevant curriculum and has the potential to radically alter how we understand culture and language in…

  6. The Revitalized Tutoring Center

    ERIC Educational Resources Information Center

    Koselak, Jeremy

    2017-01-01

    One high-leverage strategy rooted in a strong research base--the revitalized tutoring center--provides a wealth of opportunity to students who may be otherwise underserved. This embedded, open-all-day tutoring center supports collaborative teacher teams by using peer tutors and community volunteers. By centralizing resources and providing supports…

  7. Ames Air Revitalization

    NASA Technical Reports Server (NTRS)

    Huang, Roger Z.

    2015-01-01

    This is an informal presentation presented to the University of Colorado, Boulder Bioastronautics group seminar. It highlights the key focal areas of the Air Revitalization Group research over the past year, including progress on the CO2 Removal and Compression System, testing of CDRA drying bed configurations, and adsorption research.

  8. Programming of Urban Revitalization

    NASA Astrophysics Data System (ADS)

    Biliński, Tadeusz

    2016-12-01

    The planning stage of the investment-construction process is of a crucial importance. Its overall impact on the costs, construction time and the quality of design solutions is huge. However, in practice, little attention is given to this pre-design stage, except for public buildings or other buildings of particular importance. In consequence, the results of investment and construction activities are unsatisfactory. Therefore, the issue has been given careful consideration in this paper. The paper discusses the issue of programming urban revitalization, emphasizing its socio-economic importance. To illustrate the complexity of revitalization projects planning, the author draws attention to social, economic, technical and organisational factors, such as public participation, reorganization and revaluation of land use planning, rationalization of energy use, organization and management of revitalization processes, as well as technical progress. Summarising the paper, the author concludes that in order to improve the quality of life of town residents and to protect material national heritage, it is indispensable to continuously revitalize subsequent town areas.

  9. Diagnostics of AC excited Atmospheric Pressure Plasma Jet with He for Biomedical Applications

    NASA Astrophysics Data System (ADS)

    Hori, Masaru; Takeda, Keigo; Kumakura, Takumi; Ishikawa, Kenji; Tanaka, Hiromasa; Kondo, Hiroki; Sekine, Makoto; Nakai, Yoshihiro

    2014-10-01

    Atmospheric pressure plasma jets (APPJ) are frequently used for biomedical applications. Reactive species generated by the APPJ play important roles for treatments of biomedical samples. Therefore, high density APPJ sources are required to realize the high performance. Our group has developed AC excited Ar APPJ with electron density as high as 1015 cm-3, and realized the selective killing of cancer cells and the inactivate spores of Penicillium digitatum. Recently, a new spot-size AC excited APPJ with He gas have been developed. In this study, the He APPJ was characterized by using spectroscopy. The plasma was discharged at a He flow rate of 5 slm and a discharge voltage of AC 9 kV. Gas temperature and electron density of the APPJ were measured by optical emission spectroscopy. From theoretical fitting of 2nd positive system of N2 emission (380.4 nm) and Stark broadening of Balmer β line of H atom (486.1 nm), the gas temperature and the electron density was estimated to be 299 K and 3.4. × 1015 cm-3. The AC excited He APPJ has a potential to realize high density with room temperature and become a very powerful tool for biomedical applications.

  10. Revitalizing urban waterways

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2011-07-01

    Eleven U.S. federal agencies have joined together in a new initiative to protect and revitalize urban waterways and communities. The Urban Waters Federal Partnership, announced on 24 June, is focusing on seven pilot locations to help urban communities reconnect with and revitalize their waterways, according to Lisa Jackson, administrator of the U.S. Environmental Protection Agency (EPA), which launched the initiative. “Urban waters have the potential to support healthy environments, growing businesses, and educational and recreational activities. By bringing together the experience and expertise of multiple federal partners, we have a chance to reconnect local residents, young people, and community groups with the environmental resources all around them,” she said.

  11. Spectral response of atmospheric electric field measurements near AC high voltage power lines

    NASA Astrophysics Data System (ADS)

    Silva, H. G.; Matthews, J. C.; Wright, M. D.; Shallcross, D. E.

    2015-10-01

    To understand the influence of corona ion emission on the atmospheric electrical field, measurements were made near to two AC high voltage power lines. A JCI 131 field-mill recorded the atmospheric electric field over one year. Meteorological measurements were also taken. The data series is divided in four zones (dependent on wind direction): whole zones, Z0; zone 1, Z1; zone 2, Z2; zone 3, Z3. Z3 is the least affected by corona ion emission and for that reason it is used as a reference against Z1 and Z2, which are strongly influenced by this phenomena. Analysis was undertaken for all weather days and dry days only. The Lomb-Scargle strategy developed for unevenly spaced time-series is used to calculate the spectral response of the aforementioned zones. Only frequencies above 1 minute are considered.

  12. Effects of airflow on the distribution of filaments in atmospheric AC dielectric barrier discharge

    NASA Astrophysics Data System (ADS)

    Fan, Zhihui; Qi, Haicheng; Liu, Yidi; Yan, Huijie; Ren, Chunsheng

    2016-12-01

    Atmospheric-pressure dielectric barrier discharge (DBD) accompanied by airflow has attracted a significant attention for its extensive applications. In this paper, the effects of airflow on the characteristics of the atmospheric air DBD plasma are experimentally investigated using the DBD reactor excited by a 15 kHz AC power source. In order to study the discharge filaments distribution at different flow rates, transparent conductive indium tin oxide film is used as the upper electrode, and quartz glasses are used as insulated dielectrics. Experiment results prove that the breakdown voltage is decreased and more current pulses with declined amplitudes are produced when the airflow is introduced into the discharge gap. It is confirmed that although the discharge seems to be diffuse in the presence of airflow to the naked eyes, the discharge mode remains filamentary in the intensified charge-coupled device images within a single AC cycle. By acquiring the images with a different exposure time, it can be recognized that the discharge filaments move along the flow field direction with a velocity less than the corresponding flow rate. The movement of discharge filaments is attributed to the motion of the charge induced by the airflow.

  13. Revitalizing Communities in New Mexico

    ERIC Educational Resources Information Center

    Pitzl, Jerry

    2011-01-01

    The New Mexico Rural Revitalization Initiative (NMRRI), an innovative program to enhance the growth and development of rural communities, involves schools and students as part of a holistic approach. The program requires community members to take responsibility for revitalizing their economy and fosters an entrepreneurial spirit among students.

  14. Atomic oxygen behavior at downstream of AC excited atmospheric pressure He plasma jet

    NASA Astrophysics Data System (ADS)

    Takeda, Keigo; Ishikawa, Kenji; Tanaka, Hiromasa; Sekine, Makoto; Hori, Masaru

    2016-09-01

    Applications of atmospheric pressure plasma jets (APPJ) have been investigated in the plasma medical fields such as cancer therapy, blood coagulation, etc. Reactive species generated by the plasma jet interacts with the biological surface. Therefore, the issue attracts much attentions to investigate the plasma effects on targets. In our group, a spot-size AC excited He APPJ have been used for the plasma medicine. From diagnostics of the APPJ using optical emission spectroscopy, the gas temperature and the electron density was estimated to be 299 K and 3.4 ×1015 cm-3. The AC excited He APPJ which affords high density plasma at room temperature is considered to be a powerful tool for the medical applications. In this study, by using vacuum ultraviolet absorption spectroscopy, the density of atomic oxygen on a floating copper as a target irradiated by the He APPJ was measured as a function of the distance between the plasma source and the copper wire. The measured density became a maximum value around 8 ×1013 cm-3 at 12 mm distance, and then decreased over the distance. It is considered that the behavior was due to the changes in the plasma density on the copper wire and influence of ambient air.

  15. Russian contribution to ExoMars Trace Gas Orbiter: Atmospheric Chemistry Suite (ACS)

    NASA Astrophysics Data System (ADS)

    Shakun, Alexey; Korablev, Oleg; Trokhimovskiy, Alexander; Grigoriev, Alexey; Anufreychik, Konstantin; Fedorova, Anna; Ignatiev, Nikolay; Ivanov, Yuriy; Moshkin, Boris; Kalinnikov, Yuriy; Montmessin, Franck

    2016-04-01

    Atmospheric Chemistry Suite (ACS) is a part of science payload of Trace Gas Orbiter (TGO), ExoMars mission. This project developed by European Space Agency (ESA) in collaboration with Russian Space Agency (Roscosmos). Russian contribution to ExoMars TGO is the Proton rocket and two science instruments ACS (three infrared spectrometers) and FREND (neutron detector). ACS consists of three infrared spectrometers (ACS/NIR, ACS/MIR and ACS/TIRVIM) capable to take spectral measurements from near to thermal infrared range simultaneously or separately. Spectrometric channels of ACS share common mechanical, electrical, and thermal interfaces. Electronic box (ACS/BE) provides to spectrometric channels power and data transfer interfaces. SpaceWire link is used for science data transfer and MIL-1553 link - for commanding and housekeeping data transfer. The NIR channel is an echelle spectrometer with acousto-optic tunable filter (AOTF) for the selection of diffraction orders. ACS NIR is capable to perform nadir and occultation observations. NIR covers the spectral range of 0.7-1.7 μm with resolving power of ~25000. NIR will perform unique for TGO instruments nightglow science (searching for O2, OH, NO nightglow emissions on Mars). From the 1.38 μm band NIR will do water vapour mapping in nadir and H2O vertical profiling in solar occultations. High resolution NIR measurements of 1.27 μm O2(a1Δg) dayglow will supply indirect ozone observations on the dayside on nadir. In solar occultation mode, the O2 vertical profiles will be measured from the surface (in case of low dust activity) to the 40 km altitude based on 0.76 μm absorption band. Together with MIR channel in solar occultation NIR will support the measurements of CO2 density profiles (based on 1.43 μm band) and aerosols characterization from 0.7 to 4 μm. The wide spectral range will allow not just determine aerosol particle sizes and density at different altitudes, but also distinguish between dust and ice particles

  16. Experimental investigation of photoresist etching by kHz AC atmospheric pressure plasma jet

    NASA Astrophysics Data System (ADS)

    Wang, Lijun; Zheng, Yashuang; Wu, Chen; Jia, Shenli

    2016-11-01

    In this study, the mechanism of the photoresist (PR) etching by means of a kHz AC atmospheric pressure plasma jet (APPJ) is investigated. The scanning electron (SEM) and the polarizing microscope are used to perform the surface analysis, and the mechanical profilometry is applied to diagnose the etch rate. The results show that granulated structure with numerous microparticles appears at the substrate surface after APPJ treatment, and the etch rate in the etch center is the fastest and gradually slows down to the edge of etch region. In addition, the pin-ring electrode APPJ has the highest etch rate at but easy to damage the Si wafer, the double-ring APPJ is the most stable but requires long time to achieve the ideal etch result, and the etch rate and the etch result of the multi-electrode APPJ fall in between. Ar APPJ had much higher PR etch rate and more irregular etch trace than He APPJ. It is speculated that Ar APPJ is more energetic and effective in transferring reactive species to the PR surface. It is also observed that the effective etch area initially increases and then decreases as plasma jet outlet to the PR surface distance increases.

  17. SMARTE: IMPROVING REVITALIZATION DECISIONS - OCTOBER 3, 2006

    EPA Science Inventory

    SMARTe (Sustainable Management Approaches and Revitalization Tools -electronic) is a web-based decision support tool being developed by the Office of Research and Development (ORD) in partnership with the Office of Brownfields Cleanup and Revitalization (OBCR), the Interstate Tec...

  18. Initial accomplishments of the Environmental Control and Life Support System (ECLSS) atmosphere revitalization (AR) predevelopment operational system test (POST) for the Space Station Freedom (SSF)

    NASA Technical Reports Server (NTRS)

    Dunn, Kevin H.; Bulgajewski, Peter J.

    1992-01-01

    Initial results of the integrated AR POST conducted by Boeing at Marshall Space Flight Center in 1992 are presented. The three baselined ECLSS Man Tended Capability AR assemblies were integrated and operated in a closed door chamber in which the internal atmosphere was monitored. The test provides a prerequisite checkout of the AR subsystem in preparation for longer duration tests in which the AR subsystem will be integrated with the Water Recovery Management subsystem. The integrated AR POST will serve as an early test bed to evaluate the integration of the space station ECLSS AR subsystem during design maturation.

  19. Advanced air revitalization system testing

    NASA Technical Reports Server (NTRS)

    Heppner, D. B.; Hallick, T. M.; Schubert, F. H.

    1983-01-01

    A previously developed experimental air revitalization system was tested cyclically and parametrically. One-button startup without manual interventions; extension by 1350 hours of tests with the system; capability for varying process air carbon dioxide partial pressure and humidity and coolant source for simulation of realistic space vehicle interfaces; dynamic system performance response on the interaction of the electrochemical depolarized carbon dioxide concentrator, the Sabatier carbon dioxide reduction subsystem, and the static feed water electrolysis oxygen generation subsystem, the carbon dioxide concentrator module with unitized core technology for the liquid cooled cell; and a preliminary design for a regenerative air revitalization system for the space station are discussed.

  20. Language Acquisition and Language Revitalization

    ERIC Educational Resources Information Center

    O'Grady, William; Hattori, Ryoko

    2016-01-01

    Intergenerational transmission, the ultimate goal of language revitalization efforts, can only be achieved by (re)establishing the conditions under which an imperiled language can be acquired by the community's children. This paper presents a tutorial survey of several key points relating to language acquisition and maintenance in children,…

  1. Revitalizing Communities Through Drug Education

    ERIC Educational Resources Information Center

    Gregory, Robert J.

    1974-01-01

    An educational experience can be designed which, besides giving information, provides experiences and opportunities to share in revitalizing the social patterns of the community. A case study, focusing on drug abuse, serves as a base for the description of the process of community education. (Author)

  2. Air Revitalization Using Superoxides

    NASA Technical Reports Server (NTRS)

    Wydeven, Theodore; Wood, Peter C.; Spitze, L. A.

    1988-01-01

    Pellets made from powder mixtures of potassium superoxide, KO2, and calcium superoxide, Ca(O2)2, proven markedly superior to pellets of pure KO2 for adding O2 to and removing CO2 from atmospheric-pressure flow of humidified CO2 in He. Superoxides used extensively to supply O2 and scrub CO2 in variety of ambient-pressure life-support applications, including portable self-contained breathing apparatuses, spacecraft, and undersea submersible craft.

  3. Urban, Suburban, and Rural Contexts of School Districts and Neighborhood Revitalization Strategies: Rediscovering Equity in Education Policy and Urban Planning

    ERIC Educational Resources Information Center

    Silverman, Robert Mark

    2014-01-01

    This article revisits the debate about school reform and homeownership-based strategies for neighborhood revitalization. It is based on an analysis of school districts in New York State using data from the American Community Survey (ACS) and the New York State Education Department (NYSED). Findings indicate that the relationship between schools…

  4. Curriculum Revitalization Initiative at Tulane

    PubMed Central

    2015-01-01

    Tulane School of Public Health and Tropical Medicine launched its curriculum revitalization initiative to examine the Master of Public Health degrees (MPH). The initiative will enhance excellence in MPH education and incorporate innovative teaching approaches. Taskforces determined the MPH core should provide the foundation for public health, integrate knowledge across public health areas, and develop skills and methods needed in practice. The MPH is being updated to provide specialized study that builds skills and practical applications based on theory and evidence-based approaches. Eleven graduate certificates were developed to provide a second area of specialization. Practica are viewed as increasingly important for students without practical experience. Teaching methods will incorporate more technology including online modules for a blended classroom approach. PMID:25706011

  5. Revitalizing Inner-City Minority Communities

    ERIC Educational Resources Information Center

    Ikemma, William N.

    1977-01-01

    The black neighborhood based business environment in Houston, Texas, is examined as an example of minority community revitalization. A number of strategies for improving black community development in the nation's cities are suggested. (GC)

  6. Development of a Test Facility for Air Revitalization Technology Evaluation

    NASA Technical Reports Server (NTRS)

    Lu, Sao-Dung; Lin, Amy; Campbell, Melissa; Smith, Frederick; Curley, Su

    2007-01-01

    Development of new air revitalization system (ARS) technology can initially be performed in a subscale laboratory environment, but in order to advance the maturity level, the technology must be tested in an end-to-end integrated environment. The Air Revitalization Technology Evaluation Facility (ARTEF) at the NASA Johnson Space Center serves as a ground test bed for evaluating emerging ARS technologies in an environment representative of spacecraft atmospheres. At the center of the ARTEF is a hypobaric chamber which serves as a sealed atmospheric chamber for closed loop testing. A Human Metabolic Simulator (HMS) was custom-built to simulate the consumption of oxygen, and production of carbon dioxide, moisture and heat of up to eight persons. A multitude of gas analyzers and dew point sensors are used to monitor the chamber atmosphere upstream and downstream of a test article. A robust vacuum system is needed to simulate the vacuum of space. A reliable data acquisition and control system is required to connect all the subsystems together. This paper presents the capabilities of the integrated test facility and some of the issues encountered during the integration.

  7. Dependence of Ozone Generation on Gas Temperature Distribution in AC Atmospheric Pressure Dielectric Barrier Discharge in Oxygen

    NASA Astrophysics Data System (ADS)

    Takahashi, Go; Akashi, Haruaki

    AC atmospheric pressure multi-filament dielectric barrier discharge in oxygen has been simulated using two dimensional fluid model. In the discharge, three kinds of streamers have been obtained. They are primary streamers, small scale streamers and secondary streamers. The primary streamers are main streamers in the discharge and the small scale streamers are formed after the ceasing of the primary streamers. And the secondary streamers are formed on the trace of the primary streamers. In these streamers, the primary and the small scale streamers are very effective to generate O(3P) oxygen atoms which are precursor of ozone. And the ozone is generated mainly in the vicinity of the dielectrics. In high gas temperature region, ozone generation decreases in general. However, increase of the O(3P) oxygen atom density in high gas temperature region compensates decrease of ozone generation rate coefficient. As a result, amount of ozone generation has not changed. But if the effect of gas temperature was neglected, amount of ozone generation increases 10%.

  8. Relationship between atmospheric methane lifetime, isotope budget and effective sink enrichments simulated in AC-GCM EMAC

    NASA Astrophysics Data System (ADS)

    Gromov, Sergey; Steil, Benedikt

    2016-04-01

    In his note adamant for interpreting paleoclimate isotope-resolved CH4 records, Tans [1] has emphasised the large disparity in the timescales of abundance and isotope ratio changes in the atmospheric CH4. Derived using a simple two-box model, quantitatively this result is consistent for hemispherically average (homogeneous) CH4 emitted and removed by yet homogenous and invariable sources and sinks. However, neither the abundance of methane nor its sources and sink rate (determined largely by OH and temperature) are spatiotemporally even. The situation is further complicated by non-linear convolution of photochemistry and mixing/transport acting between source regions and a regarded location. Compared to about 10 years on average in the troposphere, local CH4 lifetime varies from 15 months (near the surface in tropics) to hundreds of years at high latitudes in winter. How does the local isotope enrichment of CH4 (resulting from sink fractionation processes) correspond to that? Will using a realistic atmospheric model indicate importance of the abovementioned issues, and for which paleoclimate records? Inspired by these questions, we designed a similar to [1] experiment implemented, however, in the 3D AC-GCM model EMAC [2; 3] which resolves 13C/12C and 2H/1H isotope chemistry, 14CH4 abundance and methane photochemical sinks including reactions with OH, O(1D), Cl with respective kinetic isotope effects up to the middle atmosphere (about 80 km). We simulate long-term equilibration of CH4 abundance and isotope ratios for several emission magnitudes/distributions and OH fields, subsequently perturbed by the pulse change in source strengths or isotope signatures. The resulting sensitivities of effective 13C/12C and 2H/1H enrichments in atmospheric methane (13Cɛ and 2Hɛ, respectively) are important for gauging the isotope signatures of CH4 sources derived for present and from paleo-records of CH4. The simulated hemispheric difference in 13Cɛ correspond to that of [1

  9. Preprototype independent air revitalization subsystem

    NASA Technical Reports Server (NTRS)

    Schubert, F. H.; Hallick, T. M.; Woods, R. R.

    1982-01-01

    The performance and maturity of a preprototype, three-person capacity, automatically controlled and monitored, self-contained independent air revitalization subsystem were evaluated. The subsystem maintains the cabin partial pressure of oxygen at 22 kPa (3.2 psia) and that of carbon dioxide at 400 Pa (3 mm Hg) over a wide range of cabin air relative humidity conditions. Consumption of water vapor by the water vapor electrolysis module also provides partial humidity control of the cabin environment. During operation, the average carbon dioxide removal efficiency at baseline conditions remained constant throughout the test at 84%. The average electrochemical depolarized concentrator cell voltage at the end of the parametric/endurance test was 0.41 V, representing a very slowly decreasing average cell voltage. The average water vapor electrolysis cell voltage increased only at a rate of 20 mu/h from the initial level of 1.67 V to the final level of 1.69 V at conclusion of the testing.

  10. How utilizes can revitalize industry

    SciTech Connect

    De Vaul, D.; Bartsch, C.

    1993-12-31

    During the first weeks of his presidency, Bill Clinton asserted that the nation`s industries must modernize if Americans are to enjoy a rising standard of living. He noted that inadequate knowledge about new production technologies and inadequate capital for plant improvements were making it hard for manufacturers, particularly small and midsized firms, to improve their productivity and economic competitiveness. And though he said his administration would stress the benefits of government research, technology transfer, and financial assistance, President Clinton acknowledged that Washington needs new partners to help modernize U.S. industrial processes. Electric utilities are likely candidates. They have considerable technical expertise and access to large sums of capital that could help industry improve its productivity. Fortuitously, power companies also would benefit by such a partnership stimulating local economic activity and better managing electricity demands. Although many utilities pursue so-called demand-side management programs for their commercial and residential customers, most have not focused much attention on the industrial sector, in part because achieving industrial energy efficiency requires more specialized expertise than do routine energy audits to improve the insulation and lighting of homes and commercial buildings. Yet the reasons to target industry are compelling: Industrial firms consume more than 35 percent of the electricity in the United States, and investment in retooling manufacturing operations with energy-efficient and productive equipment could help spur economic revitalization.

  11. SMARTE: HELPING COMMUNITIES OVERCOME OBSTACLES TO REVITALIZATION - JUNE 28, 2006

    EPA Science Inventory

    SMARTe (Sustainable Management Approaches and Revitalization Tools -electronic) is a web-based decision support tool being developed by the Office of Research and Development (ORD) in partnership with the Office of Brownfields Cleanup and Revitalization (OBCR), the Interstate Tec...

  12. SMARTE: HELPING COMMUNITIES EVALUATE REUSE OPTIONS AND OVERCOME REVITALIZATION OBSTACLES

    EPA Science Inventory

    SMARTe (Sustainable Management Approaches and Revitalization Tools electronic) is a web-based decision support tool being developed by the Office of Research and Development (ORD) in partnership with the Office of Brownfields and Land Revitalization (OBLR), the Interstate Techn...

  13. Revitalization of the NASA Langley Research Center's Infrastructure

    NASA Technical Reports Server (NTRS)

    Weiser, Erik S.; Mastaler, Michael D.; Craft, Stephen J.; Kegelman, Jerome T.; Hope, Drew J.; Mangum, Cathy H.

    2012-01-01

    The NASA Langley Research Center (Langley) was founded in 1917 as the nation's first civilian aeronautical research facility and NASA's first field center. For nearly 100 years, Langley has made significant contributions to the Aeronautics, Space Exploration, and Earth Science missions through research, technology, and engineering core competencies in aerosciences, materials, structures, the characterization of earth and planetary atmospheres and, more recently, in technologies associated with entry, descent, and landing. An unfortunate but inevitable outcome of this rich history is an aging infrastructure where the longest serving building is close to 80 years old and the average building age is 44 years old. In the current environment, the continued operation and maintenance of this aging and often inefficient infrastructure presents a real challenge to Center leadership in the trade space of sustaining infrastructure versus not investing in future capabilities. To address this issue, the Center has developed a forward looking revitalization strategy that ties future core competencies and technical capabilities to the Center Master Facility Plan to maintain a viable Center well into the future. This paper documents Langley's revitalization strategy which integrates the Center's missions, the Langley 2050 vision, the Center Master Facility Plan, and the New Town repair-by-replacement program through the leadership of the Vibrant Transformation to Advance Langley (ViTAL) Team.

  14. One-man electrochemical air revitalization system evaluation

    NASA Technical Reports Server (NTRS)

    Schbert, F. H.; Marshall, R. D.; Hallick, T. M.; Woods, R. R.

    1976-01-01

    A program to evaluate the performance of a one man capacity, self contained electrochemical air revitalization system was successfully completed. The technology readiness of this concept was demonstrated by characterizing the performance of this one man system over wide ranges in cabin atmospheric conditions. The electrochemical air revitalization system consists of a water vapor electrolysis module to generate oxygen from water vapor in the cabin air, and an electrochemical depolarized carbon dioxide concentrator module to remove carbon dioxide from the cabin air. A control/monitor instrumentation package that uses the electrochemical depolarized concentrator module power generated to partially offset the water vapor electrolysis module power requirements and various structural fluid routing components are also part of the system. The system was designed to meet the one man metabolic oxygen generation and carbon dioxide removal requirements, thereby controlling cabin partial pressure of oxygen at 22 kN/sq m and cabin pressure of carbon dioxide at 400 N/sq m over a wide range in cabin air relative humidity conditions.

  15. GET SMARTE: DECISION TOOLS TO REVITALIZE BROWNFIELDS

    EPA Science Inventory

    SMARTe (Sustainable Management Approaches and Revitalization Tools-electronic) is an open-source, web-based, decision-support system for developing and evaluating future use scenarios for potentially contaminated sites (i.e., brownfields). It contains resources and analysis tools...

  16. Learning Communities: A Paradigm for Educational Revitalization.

    ERIC Educational Resources Information Center

    Smith, Barbara Leigh; Hunter, M. Rosetta

    1988-01-01

    Describes a collaborative program initiated by Evergreen State College and Seattle Central Community College in Washington to promote faculty revitalization, curricular reform, and interinstitutional articulation. Examines the new curriculum of Seattle Central, as an intentionally designed "learning community," structured to sustain academic…

  17. Some Basics of Indigenous Language Revitalization.

    ERIC Educational Resources Information Center

    Reyhner, Jon

    Drawing from papers presented at the five "Stabilizing Indigenous Languages" symposia held since 1994, this paper recommends strategies for language revitalization at various stages of language loss. Based on a study of minority languages worldwide, Joshua Fishman postulated a continuum of eight stages of language loss, ranging from the…

  18. An integrated regenerative air revitalization system for spacecraft

    NASA Technical Reports Server (NTRS)

    Noyes, G. P.; Heppner, D. B.; Schubert, F. H.; Quattrone, P. D.

    1982-01-01

    Progress towards development of an air revitalization system (ARS) for spacecraft breathable atmosphere regeneration is assessed, and a preliminary design for a one-person ARS is described. The ARS is considered a necessary component of any permanently manned orbital station, and studies have demonstrated that penalties for expendable air supplies justify an ARS for missions longer than 40 days. CO2 must be removed and O2 returned along with N2, which can be extracted from hydrazine, with the H2 component returning to the operation of the CO2 reduction subsystem. An experimental ARS (ARX-1) features a cabin humidity control unit, a CO2 concentrator, an air-cooled CO2 reduction reactor, an oxygen generator (electrolysis), the hydrazine N2 generator, and a water handling unit. A 120-day test demonstrated one-button startup and 480 hr operation in a normal mode.

  19. Amplification of multi-gigawatt 3 ps pulses in an atmospheric CO2 laser using ac Stark effect.

    PubMed

    Tochitsky, S Ya; Pigeon, J J; Haberberger, D J; Gong, C; Joshi, C

    2012-06-18

    The 3 ps pulses are amplified to ~20 GW peak power in a TEA CO(2) laser using ac Stark broadening. Demonstration of such broadband coherent amplification of 10 μm pulses opens opportunities for a powerful mid-IR source at a high-repetition rate.

  20. A Revitalized USAF Culture of Innovation

    DTIC Science & Technology

    2013-11-01

    i   SQUADRON OFFICER COLLEGE AIR UNIVERSITY A REVITALIZED USAF CULTURE OF INNOVATION By Capt Vito Bussmann, Capt Gabriel Gassie, Capt...NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Air University,Squadron Officer College ,Maxwell AFB,AL...inputs from senior leadership on-site at Air University and Squadron Officer College to guide the direction of our research. Our research placed an

  1. Urban revitalization and displacement: types, causes, and public policy

    SciTech Connect

    Feagin, J.R.

    1981-05-01

    The policy research report reviews the scholarly and print media literatures on urban revitalization. The extent of revitalization; the incumbent or occupant upgrading; gentrification (displacement of low- and moderate-income households by better-off households); gentrification and displacement from all causes; and the role of powerful actors in revitalization are discussed. Public policy dealing with land use and development in urban areas is discussed. Future research needs are indicated.

  2. Ecological Revitalization: Turning Contaminated Properties Into Community Assets

    EPA Pesticide Factsheets

    This document provides technical information to assist property managers and other stakeholders better understand, coordinate, and conduct ecological revitalization at contaminated properties during cleanup

  3. Revitalizing the Small Town Mainstreet. Hard Times: Communities in Transition.

    ERIC Educational Resources Information Center

    Cook, Edward A.; Bentley, Marion T.

    Presenting a base of general information that local business people and government officials involved with downtown revitalization should be familiar with in order to understand the range of options available and factors that will influence the outcomes of any revitalization program, the paper summarizes current theories, trends, studies, and…

  4. 78 FR 69629 - Revitalization of the AM Radio Service

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-20

    ... COMMISSION 47 CFR Part 73 Revitalization of the AM Radio Service AGENCY: Federal Communications Commission... broadcast radio service, and to ease regulatory burdens on existing AM broadcasters. The Commission also solicits further comments and suggestions designed to foster the revitalization of the AM broadcast...

  5. Revitalization - an organizational program for the individual

    SciTech Connect

    Brewer, J.M.

    1983-07-01

    Progressive devitalization is a malady that afflicts many workers resulting in tremendous costs to organizations. This malady has long been recognized by management but little has been done to treat it. A new approach to the problem has been insitituted at Lawrence Livermore National Laboratory, in the form of a group program called Revitalization. Early results have been very encouraging. The program will continue to be designed and improved in the hope of bringing more productivity to the organization and self-esteem to the individual.

  6. Thirsty Walls: A New Paradigm for Air Revitalization in Life Support

    NASA Technical Reports Server (NTRS)

    Graf, John; Brennecke, Joan; Weislogel, Mark

    2015-01-01

    Carbon Dioxide removal systems on submarines are compact and reliable. They use solubility chemistry. They spray a Carbon Dioxide adsorbing chemical directly into the air stream, and allow the liquid to settle. Carbon Dioxide removal systems on ISS are large and need repair. They use adsorption chemistry. They force air through a bed packed with granular zeolite, and heat the bed to desorb the Carbon Dioxide. The thermal cycles cause the zeolite to dust. New advances in additive manufacturing, and a better understanding of uid behavior in microgravity make it possible to expose a liquid directly to air in a microgravity environment. It is now practical to use submarine style solubility chemistry for atmosphere revitalization in space. It is now possible to develop space systems that achieve submarine levels of reliability. New developments in Ionic Liquid research make it possible to match the solubility performance characteristics of MEA used on submarines - with Ionic Liquids that do not release chemical vapors into the air. "Thirsty Walls" provide gentle, passive contact between ventilation air and Air Revitalization functions of temperature control, relative humidity control, and Carbon Dioxide removal. "Thirsty Walls" eliminates the need of large blowers and compressors that need to force air at high velocities through restrictive Air Revitalization hardware.

  7. Electrochemical air revitalization system optimization investigation

    NASA Technical Reports Server (NTRS)

    Woods, R. R.; Schubert, F. H.; Hallick, T. M.

    1975-01-01

    A program to characterize a Breadboard of an Electrochemical Air Revitalization System (BEARS) was successfully completed. The BEARS is composed of three components: (1) a water vapor electrolysis module (WVEM) for O2 production and partial humidity control, (2) an electrochemical depolarized carbon dioxide concentrator module (EDCM) for CO2 control, and (3) a power-sharing controller, designed to utilize the power produced by the EDCM to partially offset the WVEM power requirements. It is concluded from the results of this work that the concept of electrochemical air revitalization with power-sharing is a viable solution to the problem of providing a localized topping force for O2 generation, CO2 removal and partial humidity control aboard manned spacecraft. Continued development of the EARS concept is recommended, applying the operational experience and limits identified during the BEARS program to testing of a one-man capacity system and toward the development of advanced system controls to optimize EARS operation for given interfaces and requirements. Successful completion of this development will produce timely technology necessary to plan future advanced environmental control and life support system programs and experiments.

  8. Revitalization of Basic Business Education at All Instructional Levels. National Business Education Yearbook, No. 20.

    ERIC Educational Resources Information Center

    Jones, Eugene, Ed.

    This yearbook, consisting of 15 papers, deals with the revitalization of basic business education at all levels of instruction. The focus of the papers is on revitalizing basic business education in general, revitalizing the subject areas of basic business eudcation, revitalizing business education through instructional strategies, and…

  9. Design and Sizing of the Air Revitalization System for Altair Lunar Lander

    NASA Technical Reports Server (NTRS)

    Allada, Rama Kumar

    2009-01-01

    Designing closed-loop Air Revitalization Systems (ARS) for human spaceflight applications requires a delicate balance between designing for system robustness while minimizing system power and mass requirements. This presentation will discuss the design of the ARS for the Altair Lunar Lander. The presentation will illustrate how dynamic simulations, using Aspen Custom Modeler, were used to develop a system configuration with the ability to control atmospheric conditions under a wide variety of circumstances while minimizing system mass/volume and the impact on overall power requirements for the Lander architecture.

  10. Brownfields Shifting Gears: Driving Toward Auto Sector Property Revitalization

    EPA Pesticide Factsheets

    This is an overview of community success stories. By building strong partnerships and setting priorities for recovery and revitalization, the public and private sectors are realizing a great deal of success in addressing idle industrial brownfields.

  11. Development And Evaluation Of Sustainability Criteria For Land Revitalization

    EPA Science Inventory

    Land revitalization offers the opportunity to reconsider the functional roles that individual land parcels can contribute to sustaining environmental systems. Although the ability of individual parcels to make these systems more resilient and move more toward sustainability may ...

  12. SMARTE: IMPROVING REVITALIZATION DECISIONS - PRESENTATION FOR ETV INTERNATIONAL FORUM

    EPA Science Inventory

    SMARTe (Sustainable Management Approaches and Revitalization Tools - electronic) is an open-source, web-based, decision-support system for developing and evaluating alternative reuse scenarios for potentially contaminated sites (e.g., brownfields). It is being developed collabora...

  13. Land Revitalization in Arkansas, Louisiana, New Mexico, Oklahoma, and Texas

    EPA Pesticide Factsheets

    Land Revitalization Program is focused on restoring land and other natural resources into sustainable community assets that maximize beneficial economic, ecological and social uses to ensure protection of human health and the environment.

  14. Brownfields Portfields: Charting a Course for Port Revitalization

    EPA Pesticide Factsheets

    The following case studies illustrate how the Pilot Port communities and the Portfields partnership are leveraging resources and promoting innovative approaches to invigorate and enhance local community revitalization efforts.

  15. LaRC 20-Year Center Revitalization Plan

    NASA Technical Reports Server (NTRS)

    Mangum, Cathy H.; Harris, Charles E.; Allen, Cheryl L.; Craft, Stephen J.; Hope, Drew J.; Kegelman, Jerome T.; Mastaler, Michael D; Weiser, Erik S.

    2012-01-01

    LaRC has developed a 20-Year Center Revitalization Plan. The objective of this plan is to assure that the center infrastructure is sustainable for the long-term and that the center will have the essential facilities and laboratories to execute the future NASA mission. The plan was developed by a centerwide team, VITAL, and was approved by the Center Leadership Council (CLC) in March 2012. The revitalization plan will be implemented through the Center Master Planning process.

  16. Energy efficiency in military housing: Monitoring to support revitalization guidebook

    SciTech Connect

    Levins, W.P.; Ternes, M.P.

    1994-11-01

    Oak Ridge National Laboratory is working with the US Army, the US Air Force, and the US Department of Energy to develop a guidebook to be used by architectural and engineering firms in the design phases of military family housing revitalization projects. The purpose of the guidebook is to ensure that energy efficiency is properly addressed in revitalization projects. Monitoring space-heating and cooling energy used in houses both before and after they are revitalized is necessary in order to assess the amount of energy saved by the revitalization process. Three different methods of conducting monitoring experiments are discussed, as well as the methods of data analysis to be used. Houses will be monitored individually using standard gas and electric meters to obtain heating and cooling data for the houses. The authors recommend conducting monitoring programs at Altus Air Force Base, Oklahoma, and Fort Monmouth, New Jersey, because of their project schedules and potential for savings. They do not recommend doing any monitoring at Malmstrom Air Force Base, Montana, because of the relatively small savings that they expect revitalization to accomplish there. They do not recommend seeking out alternative sites for monitoring because of the time required to become familiar with the installation and also because revitalization schedules at alternative sites may be no better than those at the sites they inspected.

  17. Preparation of MgO Films by Atmospheric Metal-Organic Chemical Vapor Deposition as a Protective Layer in AC Plasma Display Panels

    NASA Astrophysics Data System (ADS)

    Okada, Takeru; Komaki, Toshihiro

    2008-03-01

    MgO thin films were fabricated by atmospheric metal-organic chemical vapor deposition as a protective layer of AC plasma display panels. The deposition conditions and the discharge properties of the films were evaluated. Among four Mg precursors tested, Mg(C11H19O2)2 [Mg(DPM)2] was the most suitable source material in film growth properties and discharge characteristics. The deposition rate increased with increasing vaporizing temperature and substrate temperature, and the maximum deposition rate reached 3.3 nm/s (5.1 min/µm). The films had (200) main orientations, and highly crystalline square-pyramid structures were observed in high deposition-rate films. Under the high-rate deposition condition, the firing voltage and the discharge delay of the film were comparable to those of conventional vacuum-evaporated MgO film. The discharge delay was shorter when the crystal size was larger, the work function was smaller, and the concentrations of impurities were lower.

  18. Planning for Small Town Revitalization: Economic Development Invigorates the Columbia Basin.

    ERIC Educational Resources Information Center

    Winchell, Dick G.

    1991-01-01

    Describes rural revitalization efforts for small towns in central Washington. Planning analysis by Eastern Washington University faculty and students emphasizes community participation. Details revitalization of the town of Wilbur from planning stages to final outcomes. Describes overall project results. (KS)

  19. Preparation of USY zeolite VOx supported catalysts from V(AcAc)3 and NH4VO3. Catalytic properties for the dehydrogenation of n-butane in oxygen-free atmosphere.

    PubMed

    Garcia, Elba M; Sanchez, Miguel D; Tonetto, Gabriela; Volpe, María A

    2005-12-01

    The preparation of different samples of vanadia supported on ultrastable zeolite (VO(x)/USY) is discussed. The samples were prepared in order to obtain highly dispersed V-species, avoiding the formation of crystalline vanadia and the destruction of the zeolite framework. Two methods were employed for preparing VO(x)/USY samples: an organic route using V(AcAc)3 and an inorganic route using NH4VO3. The characterization of the samples was performed with XRD, TPR, NH3-TPD, and N2 isotherms. From these results it is concluded that when VO(x) is supported on the surface of USY from acidic aqueous solution of ammonium metavanadate, the destruction of the zeolite framework is accomplished. For higher pH values in the impregnating solution, undesired V2O5 is formed on the USY surface. On the other hand, VO(x)/USY prepared from the organic precursor shows no destruction of the USY structure. In addition, highly dispersed VO(x) are formed, though for relatively high V loadings (6%) an obstruction of the zeolite windows takes place. The samples are tested as catalysts for gas phase dehydrogenation of n-butane to olefins. The catalysts prepared from NH4VO3 are almost inactive for the reaction. On the other hand, both samples prepared from V(AcAc)3 present initial conversion levels in the 8-12% range. However, the selectivity depends on the V loading, the catalysts with 6% loading being the most selective (75%). The catalytic patterns of the samples (activity and selectivity) are in agreement with the physicochemical features of the VO(x)/USY surface.

  20. Reshaping Curricula: Revitalization Programs at Three Land Grant Universities.

    ERIC Educational Resources Information Center

    Lunde, Joyce Povlacs; And Others

    This volume contains 25 papers describing large curriculum revitalization projects from 1986 through 1991 at the University of Wisconsin-Madison, the University of Minnesota, and the University of Nebraska-Lincoln. The papers are: "A Theoretical Context for Designing Curricula in the Agricultural and Life Sciences" (Robert G. Kranz,…

  1. Language Revitalization and Language Pedagogy: New Teaching and Learning Strategies

    ERIC Educational Resources Information Center

    Hinton, Leanne

    2011-01-01

    Language learning and teaching of endangered languages have many features and needs that are quite different from the teaching of world languages. Groups whose languages are endangered try to turn language loss around; many new language teaching and learning strategies are emerging, to suit the special needs and goals of language revitalization.…

  2. GET SMARTE: DECISION TOOLS TO REVITALIZE COMMUNITIES (MAY 2006)

    EPA Science Inventory

    SMARTe (Sustainable Management Approaches and Revitalization Tools-electronic) is an open-source, web-based, decision-support system for developing and evaluating future use scenarios for potentially contaminated sites (i.e., brownfields). It contains resources and analysis tools...

  3. Urban Revitalization and Entrepreneurial Strategies. Digest Number 97-8.

    ERIC Educational Resources Information Center

    Schuyler, Gwyer

    Urban revitalization is an economic and social strategy that has been necessitated by decreased interest in both residence and commercialization within major cities. Urban business environments are confronted with many unique socioeconomic challenges, including discrimination against residents, negative stereotypes of urban areas, and inaccurate…

  4. Cultivating Common Ground: Cultural Revitalization in Anishinaabe and Anthropological Discourse

    ERIC Educational Resources Information Center

    Willow, Anna J.

    2010-01-01

    In this article, the author explores some of the most prominent ways that cultural revitalization has been contemplated within Anishinaabe and anthropological arenas of discourse. She draws reflexively on her own personal positionality and academic theoretical background as well as on her observations of how Anishinaabe anti-clear-cutting…

  5. SMARTE: IMPROVING REVITALIZATION DECISIONS - PRESENTATION IN NRMRL SEMINAR SERIES

    EPA Science Inventory

    SMARTe (Sustainable Management Approaches and Revitalization Tools-electribuc) is an open-source, web-based, decision-support system for developing and evaluating alternative reuse scenarios for potentially contaminated sites (e.g., brownfields). It is being developed collaborati...

  6. Ojibwe Language Revitalization, Multimedia Technology, and Family Language Learning

    ERIC Educational Resources Information Center

    Hermes, Mary; King, Kendall A.

    2013-01-01

    Although Indigenous language loss and revitalization are not new topics of academic work nor new areas of community activism (e.g., King, 2001; Grenoble & Whaley, 2006), increased attention has been paid in recent years to the ways that new technology can support efforts to teach and renew endangered languages such as Ojibwe. However, much of…

  7. Toward a New Era: Alternatives for Revitalizing Student Services Programs.

    ERIC Educational Resources Information Center

    Deegan, William L.

    Alternatives for revitalizing the programs and management of student services in community colleges are reviewed in this paper. First, alternatives related to student services programs are considered, including: (1) the increased use of computer-assisted counseling to integrate student services more fully with mainstream academic activities; (2)…

  8. Literacy for Revitalization in the SADCC Countries of Southern Africa.

    ERIC Educational Resources Information Center

    Bhola, H. S.

    The role of literacy in the revitalization of societies is particularly meaningful in the context of the Southern African Development Coordination Conference (SADCC), a group of nine countries (Angola, Botswana, Lesotho, Malawi, Mozambique, Swaziland, Tanzania, Zambia, and Zimbabwe) surrounding or surrounded by the Republic of South Africa (RSA).…

  9. Indigenous Language Revitalization, Promotion, and Education: Function of Digital Technology

    ERIC Educational Resources Information Center

    Galla, Candace Kaleimamoowahinekapu

    2016-01-01

    Within the last two decades, there has been increased interest in how technology supports Indigenous language revitalization and reclamation efforts. This paper considers the effect technology has on Indigenous language learning and teaching, while conceptualizing how language educators, speakers, learners, and technology users holistically…

  10. The Green Book of Language Revitalization in Practice.

    ERIC Educational Resources Information Center

    Hinton, Leanne, Ed.; Hale, Ken, Ed.

    Essays in this book include the following: "Language Revitalization: An Overview" (Leanne Hinton); "Diversity in Local Language Maintenance and Restoration: A Reason for Optimism" (Anna Ash, Jessie Little Doe Fermino, Ken Hale); "Federal Language Policy and Indigenous Languages in the United States" (Leanne Hinton);…

  11. Rethinking Community-Based Indigenous Language Revitalization Using Cultural-Historical Activity Theory

    ERIC Educational Resources Information Center

    Lin, Man-Chiu Amay; Yudaw, Bowtung

    2013-01-01

    This article suggests a theoretical framework for re-examining the complex relationship of language, literacy, and cultural practices, across multiple generations in the context of community-based Indigenous language revitalization. In the scholarship of Indigenous language revitalization and education, researchers have shifted from viewing…

  12. Learning Needs Analysis of Collaborative E-Classes in Semi-Formal Settings: The REVIT Example

    ERIC Educational Resources Information Center

    Mavroudi, Anna; Hadzilacos, Thanasis

    2013-01-01

    Analysis, the first phase of the typical instructional design process, is often downplayed. This paper focuses on the analysis concerning a series of e-courses for collaborative adult education in semi-formal settings by reporting and generalizing results from the REVIT project. REVIT, an EU-funded research project, offered custom e-courses to…

  13. Objectives at the Crossroads: Critical Theory and Self-Determination in Indigenous Language Revitalization

    ERIC Educational Resources Information Center

    Albury, Nathan John

    2015-01-01

    Indigenous language revitalization is a popular focus of critical theorists. From the perspective of sociolinguists, critical theory interrogates language policies to name and shame inequalities and propose solutions to correct injustices and emancipate the disadvantaged. From a broader perspective, language revitalization policy also resides…

  14. 77 FR 16251 - Announcement of Funding Awards, HOPE VI Revitalization Grant Program, Fiscal Year 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-20

    ... URBAN DEVELOPMENT Announcement of Funding Awards, HOPE VI Revitalization Grant Program, Fiscal Year 2010... funding awards. SUMMARY: In accordance with Section 102(a)(4)(C) of the Department of Housing and Urban..., contact Ms. Susan Wilson, Director, Office of Urban Revitalization, Office of Public and Indian...

  15. From Documenting to Revitalizing an Endangered Language: Where Do Applied Linguists Fit?

    ERIC Educational Resources Information Center

    Penfield, Susan D.; Tucker, Benjamin V.

    2011-01-01

    This paper explores the distance between documenting and revitalizing endangered languages and indicates critical points at which applied linguistics can play a role. We look at language documentation, language revitalization and their relationship. We then provide some examples from our own work. We see the lack of applied linguistics as a…

  16. 75 FR 71137 - Announcement of Funding Awards for the HOPE VI Revitalization Grant Program for Fiscal Year 2009

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ... URBAN DEVELOPMENT Announcement of Funding Awards for the HOPE VI Revitalization Grant Program for Fiscal... Funding Availability (NOFA) for the HOPE VI Revitalization grant program. This announcement contains the... concerning the HOPE VI Revitalization grant awards, contact the Ms. Leigh van Rij, Office of Public...

  17. Mathematical model of one-man air revitalization system

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A mathematical model was developed for simulating the steady state performance in electrochemical CO2 concentrators which utilize (NMe4)2 CO3 (aq.) electrolyte. This electrolyte, which accommodates a wide range of air relative humidity, is most suitable for one-man air revitalization systems. The model is based on the solution of coupled nonlinear ordinary differential equations derived from mass transport and rate equations for the processes which take place in the cell. The boundary conditions are obtained by solving the mass and energy transport equations. A shooting method is used to solve the differential equations.

  18. Integrated Evaluation of Closed Loop Air Revitalization System Components

    NASA Technical Reports Server (NTRS)

    Murdock, K.

    2010-01-01

    NASA s vision and mission statements include an emphasis on human exploration of space, which requires environmental control and life support technologies. This Contractor Report (CR) describes the development and evaluation of an Air Revitalization System, modeling and simulation of the components, and integrated hardware testing with the goal of better understanding the inherent capabilities and limitations of this closed loop system. Major components integrated and tested included a 4-Bed Modular Sieve, Mechanical Compressor Engineering Development Unit, Temperature Swing Adsorption Compressor, and a Sabatier Engineering and Development Unit. The requisite methodolgy and technical results are contained in this CR.

  19. Vapor compression distiller and membrane technology for water revitalization

    NASA Technical Reports Server (NTRS)

    Ashida, A.; Mitani, K.; Ebara, K.; Kurokawa, H.; Sawada, I.; Kashiwagi, H.; Tsuji, T.; Hayashi, S.; Otsubo, K.; Nitta, K.

    1987-01-01

    Water revitalization for a space station can consist of membrane filtration processes and a distillation process. Water recycling equipment using membrane filtration processes was manufactured for ground testing. It was assembled using commercially available components. Two systems for the distillation are studied: one is absorption type thermopervaporation cell and the other is a vapor compression distiller. Absorption type thermopervaporation, able to easily produce condensed water under zero gravity, was investigated experimentally and through simulated calculation. The vapor compression distiller was studied experimentally and it offers significant energy savings for evaporation of water.

  20. The revitalization of the Public Health Service Commissioned Corps.

    PubMed

    Koop, C E; Ginzburg, H M

    1989-01-01

    The Public Health Service (PHS) is the second oldest uniformed service of the United States; its tradition commenced with the establishment of the Marine Hospital Service in 1798. Congress, in 1889, established the United States Public Health Service Commissioned Corps under the aegis of the Treasury. The Corps was created as a uniformed nonmilitary service with a distinct uniform, insignia, and with titles, pay, and retirement protocols that corresponded to those of the uniformed military services (the Armed Forces). Initially the health care system of the country, and Commissioned Corps members, were concerned with infectious and vitamin-deficiency diseases; more recently the nation's medical community has focused on cardiovascular diseases, cancer, and AIDS. A comprehensive revitalization of the Commissioned Corps began in April 1987. The intent was to restore the Commissioned Corps to its traditional leadership role as a cadre of mobile, compassionate experts ensuring the nation's health. The revitalization activities have been successful. The Commissioned Corps has approximately 5,500 active duty officers. The Surgeon General directed the development of career tracks for 11 categories of commissioned officers to increase the opportunities for professional development within the PHS and thus increase retention and professional growth. The theme for the 1989 celebration of the centennial of the Commissioned Corps is "a century of service with distinction." A hundred years from now, at the bicentennial of the Commissioned Corps, the current Surgeon General would like it to be said that the Public Health Service has had "two centuries of service with distinction."

  1. URBAN REVITALIZATION AND SEATTLE CRIME, 1982-2000.

    PubMed

    Kreager, Derek A; Lyons, Christopher J; Hays, Zachary R

    2011-11-01

    This study examines the relationship between crime and processes of urban revitalization, or gentrification. Drawing on recent urban demography research, we hypothesize that gentrification progressed rapidly in many American cities over the last decade of the 20(th) century, and that these changes had implications for area crime rates. Criminological theories hold competing hypotheses for the connections between gentrification and crime, and quantitative studies of this link remain infrequent and limited. Using two measures of gentrification and longitudinal tract-level demographic and crime data for the city of Seattle, we find that many of Seattle's downtown tracts underwent rapid revitalization during the 1990's, and that these areas 1) saw reductions in crime relative to similar tracts that did not gentrify, and 2) were areas with higher-than-average crime at the beginning of the decade. Moreover, using a within-tract longitudinal design, we find that yearly housing investments in the 1980's showed a modest positive association with crime change, while yearly investments in the 1990's showed the opposite pattern. Our findings suggest a curvilinear gentrification-crime relationship, whereby gentrification in its earlier stages is associated with small increases in crime, but gentrification in its more consolidated form is associated with modest crime declines. Implications of these results for criminological theory, urban development, and broader crime patterns are discussed.

  2. URBAN REVITALIZATION AND SEATTLE CRIME, 1982–2000

    PubMed Central

    Kreager, Derek A.; Lyons, Christopher J.; Hays, Zachary R.

    2014-01-01

    This study examines the relationship between crime and processes of urban revitalization, or gentrification. Drawing on recent urban demography research, we hypothesize that gentrification progressed rapidly in many American cities over the last decade of the 20th century, and that these changes had implications for area crime rates. Criminological theories hold competing hypotheses for the connections between gentrification and crime, and quantitative studies of this link remain infrequent and limited. Using two measures of gentrification and longitudinal tract-level demographic and crime data for the city of Seattle, we find that many of Seattle’s downtown tracts underwent rapid revitalization during the 1990’s, and that these areas 1) saw reductions in crime relative to similar tracts that did not gentrify, and 2) were areas with higher-than-average crime at the beginning of the decade. Moreover, using a within-tract longitudinal design, we find that yearly housing investments in the 1980’s showed a modest positive association with crime change, while yearly investments in the 1990’s showed the opposite pattern. Our findings suggest a curvilinear gentrification-crime relationship, whereby gentrification in its earlier stages is associated with small increases in crime, but gentrification in its more consolidated form is associated with modest crime declines. Implications of these results for criminological theory, urban development, and broader crime patterns are discussed. PMID:25505350

  3. Constitutive and herbivore-inducible glucosinolate concentrations in oilseed rape (Brassica napus) leaves are not affected by Bt Cry1Ac insertion but change under elevated atmospheric CO2 and O3.

    PubMed

    Himanen, Sari J; Nissinen, Anne; Auriola, Seppo; Poppy, Guy M; Stewart, C Neal; Holopainen, Jarmo K; Nerg, Anne-Marja

    2008-01-01

    Glucosinolates are plant secondary compounds involved in direct chemical defence by cruciferous plants against herbivores. The glucosinolate profile can be affected by abiotic and biotic environmental stimuli. We studied changes in glucosinolate patterns in leaves of non-transgenic oilseed rape (Brassica napus ssp. oleifera) under elevated atmospheric CO2 or ozone (O3) concentrations and compared them with those from transgenic for herbivore-resistance (Bacillus thuringiensis Cry1Ac endotoxin), to assess herbivory dynamics. Both elevated CO2 and O3 levels decreased indolic glucosinolate concentrations in transgenic and non-transgenic lines, whereas O3 specifically increased the concentration of an aromatic glucosinolate, 2-phenylethylglucosinolate. The herbivore-inducible indolic glucosinolate response was reduced in elevated O3 whereas elevated CO2 altered the induction dynamics of indolic and aliphatic glucosinolates. Herbivore-resistant Bt plants experienced minimal leaf damage after target herbivore Plutella xylostella feeding, but exhibited comparatively similar increase in glucosinolate concentrations after herbivory as non-transgenic plants, indicating that the endogenous glucosinolate defence was not severely compromised by transgenic modifications. The observed differences in constitutive and inducible glucosinolate concentrations of oilseed rape under elevated atmospheric CO2 and O3 might have implications for plant-herbivore interactions in Brassica crop-ecosystems in future climate scenarios.

  4. Revitalizing Indigenous Languages. Papers presented at the Annual Stabilizing Indigenous Languages Symposium (5th, Louisville, KY, May 15-16, 1998).

    ERIC Educational Resources Information Center

    Reyhner, Jon, Ed.; Cantoni, Gina, Ed.; St. Clair, Robert N., Ed.; Yazzie, Evangeline Parsons, Ed.

    This volume of conference papers examines issues and approaches in the revitalization of American Indian and other indigenous languages. Sections discuss obstacles and opportunities for language revitalization, language revitalization efforts and approaches, the role of writing in language revitalization, and using technology in language…

  5. Workers' Housing Estates In Postindustrial Cities - Modernization Or Revitalization?

    NASA Astrophysics Data System (ADS)

    Gaweł, Dariusz

    2015-09-01

    The article presents a part of the results on the physiognomy of a postindustrial city under conditions of economic transformation in Poland. The study area encompasses industrial centers located in the region of the Central Industrial District (Centralny Okręg Przemysłowy - COP) in the Świętokrzystkie and Mazowieckie voivodeships (districts). The specific urban structure of the industrial city and unemployment among its inhabitants resulting from ownership transformations generate various problems. The workers' neighborhoods and colonies, which sprouted up so quickly at the beginning of the XX century, were a supply base for the rapidly developing industrial centers. Their clear urban structure and cultural potential they possess predispose them to developing necessary repair programs. Thus, the article draws attention to this form of settlement on the one hand, and on the other characterizes the activities assumed by gminas (municipalities) in the scope of modernizing and revitalizing these areas.

  6. The revitalization of the Public Health Service Commissioned Corps.

    PubMed Central

    Koop, C E; Ginzburg, H M

    1989-01-01

    The Public Health Service (PHS) is the second oldest uniformed service of the United States; its tradition commenced with the establishment of the Marine Hospital Service in 1798. Congress, in 1889, established the United States Public Health Service Commissioned Corps under the aegis of the Treasury. The Corps was created as a uniformed nonmilitary service with a distinct uniform, insignia, and with titles, pay, and retirement protocols that corresponded to those of the uniformed military services (the Armed Forces). Initially the health care system of the country, and Commissioned Corps members, were concerned with infectious and vitamin-deficiency diseases; more recently the nation's medical community has focused on cardiovascular diseases, cancer, and AIDS. A comprehensive revitalization of the Commissioned Corps began in April 1987. The intent was to restore the Commissioned Corps to its traditional leadership role as a cadre of mobile, compassionate experts ensuring the nation's health. The revitalization activities have been successful. The Commissioned Corps has approximately 5,500 active duty officers. The Surgeon General directed the development of career tracks for 11 categories of commissioned officers to increase the opportunities for professional development within the PHS and thus increase retention and professional growth. The theme for the 1989 celebration of the centennial of the Commissioned Corps is "a century of service with distinction." A hundred years from now, at the bicentennial of the Commissioned Corps, the current Surgeon General would like it to be said that the Public Health Service has had "two centuries of service with distinction." Images p106-a p107-a p107-b p108-a p109-a PMID:2495543

  7. Revitalizing primary health care--another utopian goal?

    PubMed

    Marahatta, Sujan B

    2010-01-01

    The quest for greater efficiency, fairness and responsiveness to the expectation of the people that system serve have brought about three generations of health system reforms in the twentieth century. The first generation saw the founding of national health care systems and extension to middle income nations of social insurance systems in the 1940s and 1950s. By the late 1960s the rising costs of hospital based care, its usage by better off, inaccessibility by the poor and rural population of even the most basic services heralded second generation reforms promoting primary health care as a means of achieving the affordable universal coverage. It included the best public health strategy that is prevention and the highest ethical principle of public health that is equity. It was expected the best system for reaching households with essential and affordable care, and the best route towards universal coverage. The primary health care approach though adopted universally did not materialize its notion of translating ethos of Health for All by 2000. Overall, primary health care movement by the end of 20th century became lifeless. Since the Declaration of Alma-Ata, fundamental changes have occurred affecting health service delivery, such as economic development and financing approaches, globalization of trade and knowledge, and the shift to privatization. This is the time to develop a new vision, taking into consideration the many changes affecting global health and the strategic developments in health of recent years. With this recognition, the third generation of reforms now underway in many countries is driven by the idea of responding more to demand, assuring access for the poor and emphasizing financing rather than just provision within the public sector. The key concern is: how to translate ethos of revitalizing in the reality. Otherwise the revitalizing concept will turn into utopian goal so like HFA by 2000 strategy.

  8. Michigan State U. Joins Forces with Blighted Benton Harbor in Effort to Revitalize City.

    ERIC Educational Resources Information Center

    McMillen, Liz

    1986-01-01

    Michigan State University's Center for Urban Affairs is contributing their expertise, research skills, and volunteer time to help Benton Harbor revitalize. Faculty members and students have already completed studies on street repairs, the homeless, and hotel development. (MLW)

  9. SMARTE: HELPING COMMUNITIES OVERCOME OBSTACLES TO REVITALIZATION (04/23/07)

    EPA Science Inventory

    Sustainable Management Approaches and Revitalization Tools - electronic (SMARTe), is an open-source, web-based, decision support system for developing and evaluating future reuse scenarios for potentially contaminated land. SMARTe contains information and analysis tools for all a...

  10. GET SMARTE: A DECISION SUPPORT SYSTEM TO REVITALIZE COMMUNITIES - CABERNET 2007

    EPA Science Inventory

    Sustainable Management Approaches and Revitalization Tools - electronic (SMARTe), is an open-source, web-based, decision support system for developing and evaluating future reuse scenarios for potentially contaminated land. SMARTe contains information and analysis tools for all a...

  11. Whitewright, Texas to Receive $200,000 from EPA to Revitalize Business District

    EPA Pesticide Factsheets

    DALLAS - (March 13, 2015) The U.S. Environmental Protection Agency (EPA) recently announced the selection of the City of Whitewright, Texas to receive $200,000 to plan redevelopment and revitalization for the city's business district. The city will

  12. Environmental Assessment: Eagle Heights Housing Area Revitalization Dover Air Force Base, Delaware

    DTIC Science & Technology

    2004-07-01

    anticipated Biological Resources • Demolition and construction activities would create a short-term impact to wildlife • Most species within the Eagle ... biological resources comprises the Environmental Assessment for Eagle Heights Housing Revitalization 711510412:27 PMI039-o4 Dover Air Force Base...COVERED 00-00-2004 to 00-00-2004 4. TITLE AND SUBTITLE Environmental Assessment Eagle Heights Housing Area Revitalization Dover Air Force Base

  13. Regeneration of the dentine-pulp complex with revitalization/revascularization therapy: challenges and hopes.

    PubMed

    Lin, L M; Ricucci, D; Huang, G T-J

    2014-08-01

    The concept of regenerative endodontics has gained much attention in clinical endodontics in the past decade. One aspect of this discipline is the application of revitalization/revascularization therapies for infected and/or necrotic immature pulps in permanent teeth. Following the publication of a case report (Iwaya et al. ), investigators have been rigorously examining the types of tissues formed in the canals as well as exploring strategies to regenerate the pulp-dentine complex in revitalized teeth. This review will provide an update on the types of tissues generated in the canals after revitalization/revascularization therapy in both animal and human studies. The understanding of the role of stem cells and microenvironment in the process of wound healing resulting in either regeneration or repair will be thoroughly discussed. Stem cells and microenvironmental cues introduced into the canal during revitalization/revascularization procedures will be examined. In addition, requirement of a sterile microenvironment in the canal and vital tissue generation in revitalization/revascularization therapy will be emphasized. The challenges that we face and the hopes that we have in revitalization/revascularization therapy for regenerative endodontics will be presented.

  14. Nighttime Lights, Socioeconomic Development, and Revitalization Policies in Northeast Asia

    NASA Astrophysics Data System (ADS)

    Bennett, M.; Smith, L. C.

    2015-12-01

    Nighttime lights are typically used as a proxy for population and economic growth, yet they can also reveal socioeconomic decline. We use two night light datasets to infer socioeconomic patterns and trends in the Russian Far East, Northeast China, and North Korea, a cross-border region impacted by the 1991 collapse of the USSR. First, using the annual stable light composites from the DMSP/OLS satellites, we find that generally, nighttime lights declined in the Russian Far East, increased in Northeast China, and fluctuated in North Korea between 1992 and 2012. By 2012, lighting in most of the Russian Far East had not recovered to 1992 levels. In Northeast China, a government revitalization program may have increased lighting during the mid-2000s, suggesting sensitivity of remotely sensed nighttime lights to regional development policies. Yet caveats with DMSP/OLS data include low spatial and radiometric resolutions, saturation, and blooming. The Day/Night Band (DNB) of the Suomi NPP satellite, however, launched in October 2011, has higher quality, enabling improved monitoring of socioeconomic trends in the region. For our second night lights dataset, we use both nightly images and monthly DNB composites to make inferences regarding socioeconomic activities at finer spatial and temporal resolutions from 2012-2015. Cross-border activity in particular emerges in finer detail, allowing us to examine specific transport corridors and sites of industrial and natural resource production that involve both Russian and Chinese partners.

  15. A renewed focus on primary health care: revitalize or reframe?

    PubMed Central

    2010-01-01

    The year 2008 celebrated 30 years of Primary Health Care (PHC) policy emerging from the Alma Ata Declaration with publication of two key reports, the World Health Report 2008 and the Report of the Commission on the Social Determinants of Health. Both reports reaffirmed the relevance of PHC in terms of its vision and values in today's world. However, important challenges in terms of defining PHC, equity and empowerment need to be addressed. This article takes the form of a commentary reviewing developments in the last 30 years and discusses the future of this policy. Three challenges are put forward for discussion (i) the challenge of moving away from a narrow technical bio-medical paradigm of health to a broader social determinants approach and the need to differentiate primary care from primary health care; (ii) The challenge of tackling the equity implications of the market oriented reforms and ensuring that the role of the State in the provision of welfare services is not further weakened; and (iii) the challenge of finding ways to develop local community commitments especially in terms of empowerment. These challenges need to be addressed if PHC is to remain relevant in today's context. The paper concludes that it is not sufficient to revitalize PHC of the Alma Ata Declaration but it must be reframed in light of the above discussion. PMID:20673329

  16. Dynamic Model of the BIO-Plex Air Revitalization System

    NASA Technical Reports Server (NTRS)

    Finn, Cory; Meyers, Karen; Duffield, Bruce; Luna, Bernadette (Technical Monitor)

    2000-01-01

    The BIO-Plex facility will need to support a variety of life support system designs and operation strategies. These systems will be tested and evaluated in the BIO-Plex facility. An important goal of the life support program is to identify designs that best meet all size and performance constraints for a variety of possible future missions. Integrated human testing is a necessary step in reaching this goal. System modeling and analysis will also play an important role in this endeavor. Currently, simulation studies are being used to estimate air revitalization buffer and storage requirements in order to develop the infrastructure requirements of the BIO-Plex facility. Simulation studies are also being used to verify that the envisioned operation strategy will be able to meet all performance criteria. In this paper, a simulation study is presented for a nominal BIO-Plex scenario with a high-level of crop growth. A general description of the dynamic mass flow model is provided, along with some simulation results. The paper also discusses sizing and operations issues and describes plans for future simulation studies.

  17. 76 FR 1665 - Stakeholder Meetings Regarding the U.S.-Flag Great Lakes Fleet Revitalization Study; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-11

    ... Maritime Administration Stakeholder Meetings Regarding the U.S.-Flag Great Lakes Fleet Revitalization Study... public listening- session meetings it is conducting to gather data and comments to inform the Maritime Administration's U.S.-Flag Great Lakes Fleet Revitalization Study. MARAD inadvertently listed the incorrect...

  18. In the Name of Language: School-Based Language Revitalization, Strategic Solidarities, and State Power in the French Basque Country

    ERIC Educational Resources Information Center

    Heidemann, Kai A.

    2014-01-01

    This article explores the mobilization dynamics of a school-based minority language revitalization initiative in the French Basque Country, known as the Ikastola Movement. Bringing the study of language revitalization into dialogue with social movement theory, I discuss how the solidarity of Basque language activists was influenced by state-level…

  19. Strategies for Revitalizing Organizations: Regaining the Competitive Edge

    NASA Technical Reports Server (NTRS)

    Nysmith, C. Robert

    1987-01-01

    During the last decade, the United States has lost competitive stature in the world. Challenged daily by a technically sophisticated and vitalized global economy, industry and Government are examining quality and productivity initiatives with which to meet the foreign competitive challenge. At stake are our quality of life and our standard of living for the remainder of this century and beyond. Being competitive is an ongoing process, tuned to an awareness and understanding of the dynamics of the world marketplace and to the changing nature of the work environment. Solutions to America's quality and productivity problems do not exist independently within any organization or industry or at any given level of society. Success depends on commitment, partnership, meshing of goals and responsibilities, mutual respect and understanding, and a desire to be first. A change in organizational management culture is required. Traditional authoritarian management practices must give way to enlightened leadership initiatives that stress employee involvement and participation. There must be a lessening of adversarial relationships between management and labor and between industry and Government. Quality and productivity are understood to be the end result of an integrated process which begins with vigorous, committed leadership and ends with a satisfied customer. The essential elements in the revitalization process are organized in this report into seven strategies which represent the major findings of the Second NASA Symposium on Quality and Productivity. Each strategy is then broken down into its principal themes which are presented as recommendations. No one strategy can stand apart from any other; all are interrelated and work together.

  20. The revitalization of U.S. dental education.

    PubMed

    DePaola, Dominick P

    2008-02-01

    Revitalization of dental education in the United States is an imperative, but it depends mainly on the willingness of dental school faculty to make great changes. My remarks address a system of education of dental professionals in relation to other health professionals whose vision seems at times to have surpassed ours. I advocate for a revitalization of our profession in order to stand at the fore when it comes to ensuring the health and well-being of the public. Thanks to advances in molecular medicine, health care is being transformed from a system of treating disease to one that provides predictive, preemptive, and personalized care. This presentation makes recommendations for rethinking the current system of dental education in order to elevate dentistry to its rightful place as a vibrant health care leader. Dental education needs to be a source of new knowledge, discovery, and innovation to sustain its legacy as a learned profession. Graduates must be lifelong learners who can critically evaluate science and technology for the good of their patients. Future dentists should be providers of primary care, yet data suggest that the organizational structure to support this vision is lacking. The accreditation system, interrelated with licensure and National Boards, needs to set a better floor. While independence is an admirable goal, I see too much variation in the accreditation system. We must overcome fears and politics to upgrade the profession as pharmacy did when it introduced the Pharm.D. degree. With that came a change in the entire system of pharmacy education and clinical practice and recognition of pharmacists as members of an interdisciplinary health care team. Dentistry and dental education are doing a lot that is good, but we must and can do even better if the profession is to thrive as a respected member of the health professions delivering high-quality, evidence-based care to the public. Dental students, faculty, and practitioners must have command

  1. Revitalization of Energy Supply Systems in the Scale of a Town, a District and an Island

    NASA Astrophysics Data System (ADS)

    Juchimiuk, Justyna

    2016-09-01

    Model actions undertaken in HafenCity and Wilhelmsburg during IBA Hamburg 2006- 13 as well as energy transformation of Danish island of Samsø towards self-sufficiency are examples of the use of energy as one of the key factors in the design of revitalization process in various scales. An important issue is to determine the impact of renewable energy systems on design process, architecture and urbanism of revitalized structures. Article examines the programs and projects related to the processes: renewal of degraded inner-industrial areas (brownfields), ecological restoration of degraded land, the revitalization of port and underdeveloped areas in the aspects of climate protection, the use of energy from renewable sources and improvement of technical conditions of building substance while maintaining the principles of sustainable development.

  2. Your Language or Ours? Inclusion and Exclusion of Non-Indigenous Majorities in Maori and Sámi Language Revitalization Policy

    ERIC Educational Resources Information Center

    Albury, Nathan John

    2015-01-01

    Since the second half of the twentieth century, post-colonial governments have commonly sought to revitalize the indigenous languages their imperialist predecessors hoped to eradicate. Although the impetus to revitalize is shared, the question of excluding or including the non-indigenous majority in the revitalization process, and encouraging them…

  3. Language revitalization in Native North America--issues of intellectual property rights and intellectual sovereignty.

    PubMed

    Tatsch, Sheri

    2004-01-01

    Language revitalization, oral tradition and epistemology are expressions of Native peoples intellectual sovereignty, and thus the foundation for indigenous intellectual property rights. As the people of California move towards language and cultural revitalization the question arises: What constitutes or constructs the definitions of intellectual property and how can appropriation of indigenous knowledge be protected? Looking at the issues faced by the California's indigenous populace and by implication, other indigenous peoples in the United States, this essay examines how protection may be afforded under the United Nations definition of 'heritage'. Given that the holding safe of a 'culture' or 'heritage' is inclusive of language, and thus has been determined to be a human right.

  4. HESTIA Phase I Test Results: The Air Revitalization System

    NASA Technical Reports Server (NTRS)

    Wright, Sarah E.; Hansen, Scott W.

    2016-01-01

    In any human spaceflight mission, a number of Environmental Control & Life Support System (ECLSS) technologies work together to provide the conditions astronauts need to live healthily, productively, and comfortably in space. In a long-duration mission, many of these ECLSS technologies may use materials supplied by In-Situ Resource Utilization (ISRU), introducing more interactions between systems. The Human Exploration Spacecraft Test-bed for Integration & Advancement (HESTIA) Project aims to create a test-bed to evaluate ECLSS and ISRU technologies and how they interact in a high-fidelity, closed-loop, human-rated analog habitat. Air purity and conditioning are essential components within any ECLSS and for HESTIA's first test they were achieved with the Air Revitalization System (ARS) described below. The ARS provided four essential functions to the test-bed chamber: cooling the air, removing humidity from the air, removing trace contaminants, and scrubbing carbon dioxide (CO2) from the air. In this case, the oxygen supply function was provided by ISRU. In the current configuration, the ARS is a collection of different subsystems. A fan circulates the air, while a condensing heat exchanger (CHX) pulls humidity out of the air. A Trace Contaminant Removal System (TCRS) filters the air of potentially harmful contaminants. Lastly, a Reactive Plastic Lithium Hydroxide (RP-LiOH) unit removes CO2 from the breathing air. During the HESTIA Phase I test in September 2015, the ARS and its individual components each functioned as expected, although further analysis is underway. During the Phase I testing and in prior bench-top tests, the energy balance of heat removed by the CHX was not equal to the cooling it received. This indicated possible instrument error and therefore recalibration of the instruments and follow-up testing is planned in 2016 to address the issue. The ARS was tested in conjunction with two other systems: the Human Metabolic Simulator (HMS) and the

  5. Water electrolysis system - H2 and O2 generation. [for spacecraft atmosphere revitalization

    NASA Technical Reports Server (NTRS)

    Schubert, F. H.; Lee, M. K.; Davenport, R. J.; Quattrone, P. D.

    1978-01-01

    An oxygen generation system design based on the static feed water electrolysis concept is described. The system is designed to generate 4.20 kg/d of oxygen to satisfy the metabolic needs of a three-person crew, to compensate for spacecraft leakage, and to provide the oxygen required by the electrochemical depolarized CO2 concentrator. The system has a fixed hardware weight of 75 kg, occupies a volume of 0.11 cu m, and requires only 1.1 kw of electrical power. The static feed electrolysis concept is discussed, and experimental data on the high-performance electrode are presented.

  6. Evaluation of Sorbents for Acetylene Separation in Atmosphere Revitalization Loop Closure

    NASA Technical Reports Server (NTRS)

    Abney, Morgan B.; Miller, Lee A.; Barton, Katherine

    2011-01-01

    State-of-the-art carbon dioxide reduction technology uses a Sabatier reactor to recover water from metabolic carbon dioxide. In order to maximize oxygen loop closure, a byproduct of the system, methane, must be reduced to recover hydrogen. NASA is currently exploring a microwave plasma methane pyrolysis system for this purpose. The resulting product stream of this technology includes unreacted methane, product hydrogen, and acetylene. The hydrogen and the small amount of unreacted methane resulting from the pyrolysis process can be returned to the Sabatier reactor thereby substantially improving the overall efficiency of the system. However, the acetylene is a waste product that must be removed from the pyrolysis product. Two materials have been identified as potential sorbents for acetylene removal: zeolite 4A, a commonly available commercial sorbent, and HKUST-1, a newly developed microporous metal. This paper provides an explanation of the rationale behind acetylene removal and the results of separation testing with both materials.

  7. Evaluation of Sorbents for Acetylene Separation in Atmosphere Revitalization Loop Closure

    NASA Technical Reports Server (NTRS)

    Abney, Morgan B.; Miller, Lee A.; Barton, Katherine

    2012-01-01

    State-of-the-art carbon dioxide reduction technology uses a Sabatier reactor to recover water from metabolic carbon dioxide. In order to maximize oxygen loop closure, a byproduct of the system, methane, must be reduced to recover hydrogen. NASA is currently exploring a microwave plasma methane pyrolysis system for this purpose. The resulting product stream of this technology includes unreacted methane, product hydrogen, and acetylene. The hydrogen and the small amount of unreacted methane resulting from the pyrolysis process can be returned to the Sabatier reactor thereby substantially improving the overall efficiency of the system. However, the acetylene is a waste product that must be removed from the pyrolysis product. Two materials have been identified as potential sorbents for acetylene removal: zeolite 4A, a commonly available commercial sorbent, and HKUST-1, a newly developed microporous metal. This paper provides an explanation of the rationale behind acetylene removal and the results of separation testing with both materials

  8. Development of an expert system for analysis of Shuttle atmospheric revitalization and pressure control subsystem anomalies

    NASA Technical Reports Server (NTRS)

    Lafuse, Sharon A.

    1991-01-01

    The paper describes the Shuttle Leak Management Expert System (SLMES), a preprototype expert system developed to enable the ECLSS subsystem manager to analyze subsystem anomalies and to formulate flight procedures based on flight data. The SLMES combines the rule-based expert system technology with the traditional FORTRAN-based software into an integrated system. SLMES analyzes the data using rules, and, when it detects a problem that requires simulation, it sets up the input for the FORTRAN-based simulation program ARPCS2AT2, which predicts the cabin total pressure and composition as a function of time. The program simulates the pressure control system, the crew oxygen masks, the airlock repress/depress valves, and the leakage. When the simulation has completed, other SLMES rules are triggered to examine the results of simulation contrary to flight data and to suggest methods for correcting the problem. Results are then presented in form of graphs and tables.

  9. ACS: ALMA Common Software

    NASA Astrophysics Data System (ADS)

    Chiozzi, Gianluca; Šekoranja, Matej

    2013-02-01

    ALMA Common Software (ACS) provides a software infrastructure common to all ALMA partners and consists of a documented collection of common patterns and components which implement those patterns. The heart of ACS is based on a distributed Component-Container model, with ACS Components implemented as CORBA objects in any of the supported programming languages. ACS provides common CORBA-based services such as logging, error and alarm management, configuration database and lifecycle management. Although designed for ALMA, ACS can and is being used in other control systems and distributed software projects, since it implements proven design patterns using state of the art, reliable technology. It also allows, through the use of well-known standard constructs and components, that other team members whom are not authors of ACS easily understand the architecture of software modules, making maintenance affordable even on a very large project.

  10. STS-32 OV-102 air revitalization system (ARS) humidity separator problem

    NASA Technical Reports Server (NTRS)

    1990-01-01

    During STS-32, onboard Columbia, Orbiter Vehicle (OV) 102, a leakage problem at environmental control and life support system (ECLSS) air revitalization system (ARS) humidity separator A below the middeck is solved with a plastic bag and a towel. The towel inserted inside a plastic bag absorbed the water that had collected at the separator inlet.

  11. Revitalizing Educational Counseling: How Career Theory Can Inform a Forgotten Practice

    ERIC Educational Resources Information Center

    Reardon, Robert C.; Bertoch, Sara C.

    2011-01-01

    Educational counseling has declined as a counseling specialization in the United States, although the need for this intervention persists and is being met by other providers. This article illustrates how career theories such as Holland's RIASEC theory can inform a revitalized educational counseling practice in secondary and postsecondary settings.…

  12. Not Just "Situaciones de la Vida": Professionalization and Indigenous Language Revitalization in the Andes

    ERIC Educational Resources Information Center

    Hornberger, Nancy H.; Swinehart, Karl F.

    2012-01-01

    Within discourses of language endangerment, life stages such as child language acquisition, adolescent language shift, and the death of community elders figure prominently, but what of the role of other, intermediate life stages during adulthood and professional life in the course of language obsolescence or revitalization? Drawing from long-term…

  13. SMARTe: An MCDA Approach To Revitalize Communities And Restore The Environment

    EPA Science Inventory

    SMARTe (Sustainable Management Approaches and Revitalization Tools - electronic) is a free, open-source, web-based, decision-support system that helps revitalization stakeholders (communities, developers, regulators, etc.) overcome obstac...

  14. Remediation to restoration to revitalization: A path forward for AOCs progress report

    EPA Science Inventory

    At the 2016 Great Lakes Areas of Concern (AOC) Conference, researchers from the USEPA Office of Research and Development (ORD) sparked conversation about community revitalization and the different states of progress throughout the basin. The conversation was meant to provide AOC ...

  15. TOOLS FOR OVERCOMING OBSTACLES TO REVITALIZATION: SMARTE AND START-UP

    EPA Science Inventory

    In 2001, the US-German Bilateral Working Group (BWG) identified more than 40 obstacles to site revitalization which occurred in both countries. From 2001-2005, the BWG developed tools and techniques for overcoming these obstacles. Five joint workshops were held on the following r...

  16. The Role and Impact of Continuing Education on Rural Revitalization: A Case Study

    ERIC Educational Resources Information Center

    Miller, Marilyn

    2008-01-01

    This article presents the findings of a study that explored the role and impact of continuing education on rural revitalization. A community development approach, academic expertise, and a university's resources were used to assist the citizens of Montmartre, Saskatchewan, to establish Centre 48, an arts and continuing education centre. Courses…

  17. More than Words: Towards a Development-Based Approach to Language Revitalization

    ERIC Educational Resources Information Center

    Henderson, Brent; Rohloff, Peter; Henderson, Robert

    2014-01-01

    Existing models for language revitalization focus almost exclusively on language learning and use. While recognizing the value of these models, we argue that their effective application is largely limited to situations in which languages have low numbers of speakers. For languages that are rapidly undergoing language shift, but which still…

  18. Speech Community-Based Documentation, Description, and Revitalization: Kari'nja in Konomerume

    ERIC Educational Resources Information Center

    Yamada, Racquel-Maria

    2010-01-01

    Since 2005, I have been working with members of the Kari'nja community of Konomerume, Suriname to document, describe, preserve, and revitalize their heritage language, the Aretyry dialect of Kari'nja (Cariban family). Simultaneously, I have worked to develop, pilot, and articulate a model of field research that depends on participation from speech…

  19. Documentation and Revitalization of the Zhuang Language and Culture of Southwestern China through Linguistic Fieldwork

    ERIC Educational Resources Information Center

    Bodomo, Adams

    2010-01-01

    This article outlines innovative strategies, methods, and techniques for the documentation and revitalization of "Zhuang" language and culture through linguistic fieldwork. Zhuang, a Tai-Kadai language spoken mainly in the rural areas of the Guangxi Zhuang Autonomous Region of southwestern China, is the largest minority language in…

  20. Revitalizing Politics Now and Then: Howard Zinn on Dissent, Democracy, and Education

    ERIC Educational Resources Information Center

    Cooley, Aaron

    2009-01-01

    This paper presents a discussion of Howard Zinn's intellectual and political ideas. Through the analysis of selections from his immense body of work, several interrelated themes emerge. Drawing more attention to these notions of dissent and democracy is crucial to revitalizing education at all levels and vital to advancing the public discourse…

  1. "We Can't Feel Our Language": Making Places in the City for Aboriginal Language Revitalization

    ERIC Educational Resources Information Center

    Baloy, Natalie J. K.

    2011-01-01

    This article explores possibilities for extending aboriginal language education opportunities into the urban domain based on qualitative research in Vancouver, British Columbia. The author argues that aboriginal language revitalization efforts have a place in the city, as demonstrated by emerging language ideologies of urban aboriginal people…

  2. SUSTAINABLE MANAGEMENT APPROACHES AND REVITALIZATION TOOLS - ELECTRONIC (SMARTE) - 09-05-2007

    EPA Science Inventory

    Revitalization of sites potentially contaminated with environmentally toxic or hazardous materials (e.g., brownfields) is a global concern requiring a multi-disciplinary approach to mitigate the risks to human health and the environment. Many countries have committed extensive re...

  3. Revitalization of the Shared Commons: Education for Sustainability and Marginalized Cultures

    ERIC Educational Resources Information Center

    Glasson, George E.

    2010-01-01

    Education for sustainability provides a vision for revitalizing the environmental commons while preserving cultural traditions and human rights. What happens if the environmental commons is shared by two politically disparate and conflicting cultures? As in many shared common lands, what happens if one culture is dominant and represents a more…

  4. Revitalizing Curriculum Leadership: Inspiring and Empowering Your School Community. Second Edition

    ERIC Educational Resources Information Center

    Brubaker, Dale L.

    2004-01-01

    When we learn, we learn through our own experiences. So when we teach, how do we incorporate our own invaluable life lessons into a state mandated curriculum? Dale Brubaker's "Revitalizing Curriculum Leadership" provides an innovative and liberating solution to this problem. In this updated resource, the author tells why educators need to move…

  5. EPA Brownfields Grant Will Aid City of St. Helens with Plans to Revitalize Waterfront Area

    EPA Pesticide Factsheets

    (Seattle - March 17, 2015) The City of St. Helens, Oregon has been selected to receive a $200,000 Brownfields Area-Wide Planning (AWP) grant from EPA to help move towards the goal of revitalizing a former industrial property along the Columbia River waterf

  6. EPA Brownfields Grant Will Aid City of Spokane with Plans to Revitalize Hillyard Industrial Area

    EPA Pesticide Factsheets

    (Seattle - March 17, 2015) The City of Spokane, Washington has been selected to receive a $200,000 Brownfields Area-Wide Planning (AWP) grant from EPA to help move towards the goal of revitalizing a former industrial property in their city.

  7. PHASE 3 CONFERENCE OF THE U.S.-GERMANY BILATERAL WORKING GROUP BROWNFIELDS REVITALIZATION

    EPA Science Inventory

    The US-Germany Bilateral Working Group began in 1990 between the USEPA and the German Federal Ministry for Education and Research. The Working Group held a series of workshops to identify ways to facilitate revitalization of potential Brownfield Sites. In 2005, two final Conferen...

  8. Atmosphere Resource Recovery and Environmental Monitoring Trace Contaminant Control Through FY 2012

    NASA Technical Reports Server (NTRS)

    Perry, J. L.; Pruitt, M. W.; Wheeler, R. M.; Monje, O.

    2013-01-01

    Trace contaminant control has been a concern of spacecraft designers and operators from early in the progression of manned spaceflight. Significant technological advancement has occurred since the first designs were implemented in the 1960s, culminating in the trace contaminant control system currently in use aboard the International Space Station as part of the atmosphere revitalization system.

  9. Microfabricated AC impedance sensor

    DOEpatents

    Krulevitch, Peter; Ackler, Harold D.; Becker, Frederick; Boser, Bernhard E.; Eldredge, Adam B.; Fuller, Christopher K.; Gascoyne, Peter R. C.; Hamilton, Julie K.; Swierkowski, Stefan P.; Wang, Xiao-Bo

    2002-01-01

    A microfabricated instrument for detecting and identifying cells and other particles based on alternating current (AC) impedance measurements. The microfabricated AC impedance sensor includes two critical elements: 1) a microfluidic chip, preferably of glass substrates, having at least one microchannel therein and with electrodes patterned on both substrates, and 2) electrical circuits that connect to the electrodes on the microfluidic chip and detect signals associated with particles traveling down the microchannels. These circuits enable multiple AC impedance measurements of individual particles at high throughput rates with sufficient resolution to identify different particle and cell types as appropriate for environmental detection and clinical diagnostic applications.

  10. Potential Cost Savings with 3D Printing Combined With 3D Imaging and CPLM for Fleet Maintenance and Revitalization

    DTIC Science & Technology

    2014-05-01

    1 Potential Cost Savings with 3D Printing Combined With 3D Imaging and CPLM for Fleet Maintenance and Revitalization David N. Ford...2014 4. TITLE AND SUBTITLE Potential Cost Savings with 3D Printing Combined With 3D Imaging and CPLM for Fleet Maintenance and Revitalization 5a...Manufacturing ( 3D printing ) 2 Research Context Problem: Learning curve savings forecasted in SHIPMAIN maintenance initiative have not materialized

  11. AC magnetohydrodynamic microfluidic switch

    SciTech Connect

    Lemoff, A V; Lee, A P

    2000-03-02

    A microfluidic switch has been demonstrated using an AC Magnetohydrodynamic (MHD) pumping mechanism in which the Lorentz force is used to pump an electrolytic solution. By integrating two AC MHD pumps into different arms of a Y-shaped fluidic circuit, flow can be switched between the two arms. This type of switch can be used to produce complex fluidic routing, which may have multiple applications in {micro}TAS.

  12. Effects of Cabin Upsets on Adsorption Columns for Air Revitalization

    NASA Technical Reports Server (NTRS)

    LeVan, Douglas

    1999-01-01

    The National Aeronautics and Space Administration (NASA) utilizes adsorption technology as part of contaminant removal systems designed for long term missions. A variety of trace contaminants can be effectively removed from gas streams by adsorption onto activated carbon. An activated carbon adsorption column meets NASA's requirements of a lightweight and efficient means of controlling trace contaminant levels aboard spacecraft and space stations. The activated carbon bed is part of the Trace Contaminant Control System (TCCS) which is utilized to purify the cabin atmosphere. TCCS designs oversize the adsorption columns to account for irregular fluctuations in cabin atmospheric conditions. Variations in the cabin atmosphere include changes in contaminant concentrations, temperature, and relative humidity. Excessively large deviations from typical conditions can result from unusual crew activity, equipment malfunctions, or even fires. The research carried out under this award focussed in detail on the effects of cabin upsets on the performance of activated carbon adsorption columns. Both experiments and modeling were performed with an emphasis on the roll of a change in relative humidity on adsorption of trace contaminants. A flow through fixed-bed apparatus was constructed at the NASA Ames Research Center, and experiments were performed there. Modeling work was performed at the University of Virginia.

  13. Exploring and revitalizing Indigenous food networks in Saskatchewan, Canada, as a way to improve food security.

    PubMed

    Gendron, Fidji; Hancherow, Anna; Norton, Ashley

    2016-03-22

    The project discussed in this paper was designed to expand research and instigate revitalization of Indigenous food networks in Saskatchewan, Canada, by exploring the current state of local Indigenous food networks, creating a Facebook page, organizing volunteer opportunities and surveying workshop participants regarding their knowledge and interest in Indigenous foods. The survey included Likert scale questions and qualitative questions. Project activities and survey results are discussed using statistical and qualitative analysis of the themes. Results indicate that participants are very interested in learning more about, and having greater access to, traditional foods and suggest that supporting Indigenous food networks may be an appropriate response to food insecurity in communities. Elders and community members are vital players in Indigenous foods exploration and revitalization in Saskatchewan by passing on traditional education.

  14. Farm crisis and rural revitalization in south-central New York during the early twentieth century.

    PubMed

    Osterud, Grey

    2010-01-01

    In contrast to both the critique of rural backwardness made by the Country Life Movement and the lament about rural declension expressed by proponents of agrarianism, the history of the Nanticoke Valley of south-central New York State demonstrates the possibilities for rural revitalization that lay in connections between the countryside and the city. In the early twentieth century, as long-settled families departed for urban employment, European immigrant families escaping the mines and mills bought abandoned farms. Motorized transport enabled farming families to send household members to the city each day and furnished them with a local market for their produce. This flexible combination of subsistence production, wage labor, and petty commodity production revitalized the rural economy and sustained the community in spite of the consolidation of the dairy industry. This essay explores the social changes that accompanied this profound reorientation of local life.

  15. Specifics of Formal and Legal Issues in Processes of Revitalizing Post-Industrial Buildings

    NASA Astrophysics Data System (ADS)

    Kochański, Paweł

    2016-12-01

    The article deals with issues from the initial phase of the investment process connected with revitalizing postindustrial buildings: planning and programming investments in the functional and financial scope, as well as designing. The described formal and legal aspects are the result of a study of a few projects concerning the adaptation of buildings to serving a new function in Zielona Góra and Żaganie. The conclusions drawn from an individual view into each of the described problems are no different than when designing new buildings. It is not until we look into the whole preparation and design process, and gathering all experiences from the formal-legal sphere, that allows us to notice that, in the case of revitalizing postindustrial buildings and their adaptation to serve modern-day functions, a multifaceted but also specific approach is required.

  16. Designing sustainable and economically attractive brownfield revitalization options using an integrated assessment model.

    PubMed

    Schädler, S; Morio, M; Bartke, S; Rohr-Zänker, R; Finkel, M

    2011-03-01

    We describe the development of an integrated assessment model which evaluates redevelopment options of large contaminated brownfields and we present the application of the model in a case study. Aiming to support efficient and sustainable revitalization and communication between stakeholders, the presented assessment model integrates three pinnacles of brownfield revitalization: (i) subsurface remediation and site preparation costs, (ii) market-oriented economic appraisal, and (iii) the expected contribution of planned future land use to sustainable community and regional development. For the assessment, focus is set on the early stage of the brownfield redevelopment process, which is characterized by limited data availability and by flexibility in land use planning and development scope. At this stage, revealing the consequences of adjustments and alterations in planning options can foster efficiency in communication between the involved parties and thereby facilitates the brownfield revitalization process. Results from the case-study application indicate that the integrated assessment provides help in the identification of land use options beneficial in both a sustainable and an economical sense. For the study site it is shown on one hand that brownfield redevelopment is not automatically in line with sustainable regional development, and on the other hand it is demonstrated that additional contributions to sustainability are not intrinsically tied to increased costs.

  17. Effects of Cabin Upsets on Adsorption Columns for Air Revitalization

    NASA Technical Reports Server (NTRS)

    LeVan, M. Douglas

    1999-01-01

    The National Aeronautics and Space Administration (NASA) utilizes adsorption technology as part of contaminant removal systems designed for long term missions. A variety of trace contaminants can be effectively removed from gas streams by adsorption onto activated carbon. An activated carbon adsorption column meets NASA's requirements of a lightweight and efficient means of controlling trace contaminant levels aboard spacecraft and space stations. The activated carbon bed is part of the Trace Contaminant Control System (TCCS) which is utilized to purify the cabin atmosphere. TCCS designs oversize the adsorption columns to account for irregular fluctuations in cabin atmospheric conditions. Variations in the cabin atmosphere include changes in contaminant concentrations, temperature, and relative humidity. Excessively large deviations from typical conditions can result from unusual crew activity, equipment malfunctions, or even fires. The research carried out under this award focussed in detail on the effects of cabin upsets on the performance of activated carbon adsorption columns. Both experiments and modeling were performed with an emphasis on the roll of a change in relative humidity on adsorption of trace contaminants. A flow through fixed-bed apparatus was constructed at the NASA Ames Research Center, and experiments were performed there by W. Scot Appel under the direction of Dr. John E. Finn. Modeling work was performed at the University of Virginia and at Vanderbilt University by W. Scot Appel under the direction of M. Douglas LeVan. All three participants collaborated in all of the various phases of the research. The most comprehensive document describing the research is the Ph.D. dissertation of W. Scot Appel. Results have been published in several papers and presented in talks at technical conferences. All documents have been transmitted to Dr. John E. Finn.

  18. Tevatron AC dipole system

    SciTech Connect

    Miyamoto, R.; Kopp, S.E.; Jansson, A.; Syphers, M.J.; /Fermilab

    2007-06-01

    The AC dipole is an oscillating dipole magnet which can induce large amplitude oscillations without the emittance growth and decoherence. These properties make it a good tool to measure optics of a hadron synchrotron. The vertical AC dipole for the Tevatron is powered by an inexpensive high power audio amplifier since its operating frequency is approximately 20 kHz. The magnet is incorporated into a parallel resonant system to maximize the current. The use of a vertical pinger magnet which has been installed in the Tevatron made the cost relatively inexpensive. Recently, the initial system was upgraded with a more powerful amplifier and oscillation amplitudes up to 2-3{sigma} were achieved with the 980 GeV proton beam. This paper discusses details of the Tevatron AC dipole system and also shows its test results.

  19. ACS CCDs daily monitor

    NASA Astrophysics Data System (ADS)

    Sirianni, Marco

    2006-07-01

    This program consists of a set of basic tests to monitor, the read noise, thedevelopment of hot pixels and test for any source of noise in ACS CCDdetectors. The files, biases and dark will be used to create referencefiles for science calibration. This programme will be for the entire lifetime of ACS.For cycle 15 the program will cover 18 months 12.1.06->05.31.08and it has been divied into three different proposal each covering six months.The three poroposal are 11041-11042-11043.

  20. ac bidirectional motor controller

    NASA Technical Reports Server (NTRS)

    Schreiner, K.

    1988-01-01

    Test data are presented and the design of a high-efficiency motor/generator controller at NASA-Lewis for use with the Space Station power system testbed is described. The bidirectional motor driver is a 20 kHz to variable frequency three-phase ac converter that operates from the high-frequency ac bus being designed for the Space Station. A zero-voltage-switching pulse-density-modulation technique is used in the converter to shape the low-frequency output waveform.

  1. Current submarine atmosphere control technology.

    PubMed

    Mazurek, W

    1998-01-01

    Air purification in submarines was introduced towards the end of World War II and was limited to the use of soda lime for the removal of carbon dioxide and oxygen candles for the regeneration of oxygen. The next major advances came with the advent of nuclear-powered submarines. These included the development of regenerative and, sometimes, energy-intensive processes for comprehensive atmosphere revitalization. With the present development of conventional submarines using air-independent propulsion there is a requirement for air purification similar to that of the nuclear-powered submarines but it is constrained by limited power and space. Some progress has been made in the development of new technology and the adoption of air purification equipment used in the nuclear-powered submarines for this application.

  2. AC/DC converter

    NASA Astrophysics Data System (ADS)

    Jain, Praveen K.

    1992-08-01

    In a system such as a 20 kHz space station primary electrical power distribution system, power conversion from AC to DC is required. Some of the basic requirements for this conversion are high efficiency, light weight and small volume, regulated output voltage, close to unity input power factor, distortionless input current, soft-starting, low electromagnetic interference, and high reliability. An AC-to-DC converter is disclosed which satisfies the main design objectives of such converters for use in space. The converter of the invention comprises an input transformer, a resonant network, a current controller, a diode rectifier, and an output filter. The input transformer is for connection to a single phase, high frequency, sinusoidal waveform AC voltage source and provides a matching voltage isolating from the AC source. The resonant network converts this voltage to a sinusoidal, high frequency bidirectional current output, which is received by the current controller to provide the desired output current. The diode rectifier is connected in parallel with the current controller to convert the bidirectional current into a unidirectional current output. The output filter is connected to the rectifier to provide an essentially ripple-free, substantially constant voltage DC output.

  3. AC/RF Superconductivity

    SciTech Connect

    Ciovati, Gianluigi

    2015-02-01

    This contribution provides a brief introduction to AC/RF superconductivity, with an emphasis on application to accelerators. The topics covered include the surface impedance of normal conductors and superconductors, the residual resistance, the field dependence of the surface resistance, and the superheating field.

  4. Effects of Humidity Swings on Adsorption Columns for Air Revitalization: Modeling and Experiments

    NASA Technical Reports Server (NTRS)

    LeVan, M. Douglas; Finn, John E.

    1997-01-01

    Air purification systems are necessary to provide clean air in the closed environments aboard spacecraft. Trace contaminants are removed using adsorption. One major factor concerning the removal of trace contaminants is relative humidity. Water can reduce adsorption capacity and, due to constant fluctuations, its presence is difficult to incorporate into adsorption column designs. The purpose of the research was to allow for better design techniques in trace contaminant adsorption systems, especially for feeds with water present. Experiments and mathematical modeling research on effects of humidity swings on adsorption columns for air revitalization were carried out.

  5. Update: Partnership for the Revitalization of National Wind Tunnel Force Measurement Technology Capability

    NASA Technical Reports Server (NTRS)

    Rhew, Ray D.

    2010-01-01

    NASA's Aeronautics Test Program (ATP) chartered a team to examine the issues and risks associated with the lack of funding and focus on force measurement over the past several years, focusing specifically on strain-gage balances. NASA partnered with the U.S. Air Force's Arnold Engineering Development Center (AEDC) to exploit their combined capabilities and take a national level government view of the problem and established the National Force Measurement Technology Capability (NFMTC) project. This paper provides an update on the team's status for revitalizing the government's balance capability with respect to designing, fabricating, calibrating, and using the these critical measurement devices.

  6. Closed-loop Habitation Air Revitalization Model for Regenerative Life Support Systems

    NASA Technical Reports Server (NTRS)

    Hart, Maxwell M.

    1991-01-01

    The primary function of any life support system is to keep the crew alive by providing breathable air, potable water, edible food, and for disposal of waste. In a well-balanced or regenerative life support system, the various components are each using what is available and producing what is needed by other components so that there will always be enough chemicals in the form in which they are needed. Humans are not just users, but also one of the participating parts of the system. If a system could continuously recycle the original chemicals, this would make it virtually a Closed-loop Habitation (CH). Some difficulties in trying to create a miniature version of a CH are briefly discussed. In a miniature CH, a minimal structure must be provided and the difference must be made up by artificial parts such as physicochemical systems that perform the conversions that the Earth can achieve naturally. To study the interactions of these parts, a computer model was designed that simulates a miniature CH with emphasis on the air revitalization part. It is called the Closed-loop Habitation Air Revitalization Model (CHARM).

  7. Revitalization of open apex teeth with apical periodontitis using a collagen-hydroxyapatite scaffold.

    PubMed

    Nevins, Alan J; Cymerman, Jerome J

    2015-06-01

    An enhanced revision of the revitalization endodontic technique for immature teeth with apical periodontitis has been described. It includes the addition of collagen-hydroxyapatite scaffold to the currently practiced revascularization technique. Four cases treated in series are presented in this report, 1 case involving 2 teeth. Periapical diagnoses of immature teeth included "asymptomatic apical periodontitis," "symptomatic apical periodontitis," and "acute apical abscess." Additionally, 1 fully developed tooth that had undergone root canal treatment that failed had a periapical diagnosis of acute apical abscess. An established revascularization protocol was used for all teeth. In addition to stimulating blood clots, all teeth were filled with collagen-hydroxyapatite scaffolds. Periapical radiolucencies healed in all teeth, and diffuse radiopacity developed within the coronal portions of canal spaces. Root development with root lengthening occurred in the immature nonvital maxillary premolar that had not undergone prior treatment. The technique of adding a collagen-hydroxyapatite scaffold to the existing revitalization protocol has been described in which substantial hard tissue repair has occurred. This may leave teeth more fully developed and less likely to fracture.

  8. Revitalization of the shared commons: education for sustainability and marginalized cultures

    NASA Astrophysics Data System (ADS)

    Glasson, George E.

    2010-06-01

    Education for sustainability provides a vision for revitalizing the environmental commons while preserving cultural traditions and human rights. What happens if the environmental commons is shared by two politically disparate and conflicting cultures? As in many shared common lands, what happens if one culture is dominant and represents a more affluent society with more resources and educational opportunities? In the case of the Tal and Alkaher study (Cult Stud Sci Edu, 2009), asymmetric power differences between the dominant Israeli society and the minority Arab population yielded different environmental narratives and perceptions of students involved in learning about a mediated conflict in national park land. Similarly, marginalized indigenous cultures in Malawi, Africa share common lands with the dominant European landowners but have distinctly different environmental narratives. Although indigenous ways of living with nature contribute to the sustainability of the environment and culture, African funds of knowledge are conspicuously absent from the Eurocentric school science curriculum. In contrast, examples of experiential learning and recent curriculum development efforts in sustainability science in Malawi are inclusive of indigenous knowledge and practices and are essential for revitalizing the shared commons.

  9. Community Revitalization by Geotourism: Tourism Study with Geoscience in Wakayama, Japan

    NASA Astrophysics Data System (ADS)

    Nakakushi, T.; Hisatomi, K.; Konomatsu, M.; Furukubo, A.

    2012-12-01

    This paper presents our community-revitalization project in Wakayama Prefecture, Japan. Wakayama Prefecture is the southwestern part of the Kii Peninsula. The Kii Peninsula, especially its southern part, has many geoscientifically important natural heritages such as the volcano-plutonic complex including well exposed ring dyke in the Kumano region. Those geoheritages have been considered just as on-site educational tools, and not received enough attentions as contents for geotours. UNESCO defines that a Geopark is a geographical area where geological heritage sites are part of a holistic concept of protection, education and sustainable development. UNESCO also describes that it is necessary to also include and highlight sites of ecological, archaeological, historical and cultural value within each Geopark. In many societies, natural, cultural and social history are inextricably linked and cannot be separated. We plan to have the region registered as a geopark by Japan (or Global) Geopark Network. In the context of community-revitalization, a "regional brand" has drawn attention for its potential to attract tourists. A Geopark may contribute to establish a regional brand.

  10. USE OF INTEGRATED PLANNING TOOLS FOR REVITALIZATION: SMARTE (U.S.) AND START-UP PLAN (GERMANY)

    EPA Science Inventory

    In 2001, the US-German Bilateral Working Group (BWG) identified more than 40 obstacles to site revitalization which occurred in both countries. From 2001-2005, the BWG developed tools and techniques for overcoming these obstacles. Five joint workshops were held on the following r...

  11. Language Revitalization and the Normalization of Basque: A Study of Teacher Perceptions and Expectations in the Basque Country

    ERIC Educational Resources Information Center

    Valadez, Concepción; Etxeberria, Feli; Intxausti, Nahia

    2015-01-01

    In the Basque Country, Northern Spain, Basque (Euskera) and Spanish are official languages. In recent decades, Basque language revitalization and the efforts to make this an unmarked language (normalization) have co-existed with the rapid increase in immigration from outside the Basque region, and most recently from outside Spain. Given the…

  12. Re-Branding Urban Schools: Urban Revitalization, Social Status, and Marketing Public Schools to the Upper Middle Class

    ERIC Educational Resources Information Center

    Cucchiara, Maia

    2008-01-01

    This article examines an effort to use urban schools to promote the revitalization of a large northeastern city in the United States. In order to attract and retain professional families to a regenerated central city, downtown schools are re-branded and promoted to such families as suitable for their children. The article draws on interviews and…

  13. SUSTAINABLE MANAGEMENT APPROACHES AND REVITALIZATION TOOLS-ELECTRONIC (SMARTE): OVERVIEW AND DEMONSTRATION FOR FINAL PHASE 3 CONFERENCE

    EPA Science Inventory

    The U.S. contingent of the U.S.-German Bilateral Working Group is developing Sustainable Management Approaches and Revitalization Tools-electronic (SMARTe). SMARTe is a web-based, decision support system designed to assist stakeholders in developing and evaluating alternative reu...

  14. AC resistance measuring instrument

    DOEpatents

    Hof, P.J.

    1983-10-04

    An auto-ranging AC resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an AC excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance. After the auto-ranging and auto-compensation functions are complete, the microprocessor calculates the resistance of the load from the selected range resistance, the excitation signal, and the load voltage signal, and displays of the measured resistance on a digital display of the instrument. 8 figs.

  15. AC Resistance measuring instrument

    DOEpatents

    Hof, Peter J.

    1983-01-01

    An auto-ranging AC resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an AC excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance. After the auto-ranging and auto-compensation functions are complete, the microprocessor calculates the resistance of the load from the selected range resistance, the excitation signal, and the load voltage signal, and displays of the measured resistance on a digital display of the instrument.

  16. AC Optimal Power Flow

    SciTech Connect

    2016-10-04

    In this work, we have implemented and developed the simulation software to implement the mathematical model of an AC Optimal Power Flow (OPF) problem. The objective function is to minimize the total cost of generation subject to constraints of node power balance (both real and reactive) and line power flow limits (MW, MVAr, and MVA). We have currently implemented the polar coordinate version of the problem. In the present work, we have used the optimization solver, Knitro (proprietary and not included in this software) to solve the problem and we have kept option for both the native numerical derivative evaluation (working satisfactorily now) as well as for analytical formulas corresponding to the derivatives being provided to Knitro (currently, in the debugging stage). Since the AC OPF is a highly non-convex optimization problem, we have also kept the option for a multistart solution. All of these can be decided by the user during run-time in an interactive manner. The software has been developed in C++ programming language, running with GCC compiler on a Linux machine. We have tested for satisfactory results against Matpower for the IEEE 14 bus system.

  17. Identification of /sup 233/Ac

    SciTech Connect

    Chu, Y.Y.; Zhou, M.L.

    1983-09-01

    We report in this paper identification of the new isotope /sup 233/Ac. Uranium targets were irradiated with 28 GeV protons; after rapid retrieval of the target and separation of actinium from thorium, /sup 233/Ac was allowed to decay into the known /sup 233/Th daughter. Exhaustive chemical purification was employed to permit the identification of /sup 233/Th via its characteristic ..gamma.. radiations. The half-life derived for /sup 233/Ac from several experiments is 2.3 +- 0.3 min. The production cross section for /sup 233/Ac is 100 ..mu..b.

  18. Multi-Agent Diagnosis and Control of an Air Revitalization System for Life Support in Space

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.; Kowing, Jeffrey; Nieten, Joseph; Graham, Jeffrey s.; Schreckenghost, Debra; Bonasso, Pete; Fleming, Land D.; MacMahon, Matt; Thronesbery, Carroll

    2000-01-01

    An architecture of interoperating agents has been developed to provide control and fault management for advanced life support systems in space. In this adjustable autonomy architecture, software agents coordinate with human agents and provide support in novel fault management situations. This architecture combines the Livingstone model-based mode identification and reconfiguration (MIR) system with the 3T architecture for autonomous flexible command and control. The MIR software agent performs model-based state identification and diagnosis. MIR identifies novel recovery configurations and the set of commands required for the recovery. The AZT procedural executive and the human operator use the diagnoses and recovery recommendations, and provide command sequencing. User interface extensions have been developed to support human monitoring of both AZT and MIR data and activities. This architecture has been demonstrated performing control and fault management for an oxygen production system for air revitalization in space. The software operates in a dynamic simulation testbed.

  19. Cash management and revitalization of public medical centres in Nigeria: a strategic analysis.

    PubMed

    Agundu, Prince U C; Okon, Godwin B; Robinson, Eric T

    2007-01-01

    In times like this, when Nigeria (like many other developing countries) is bracing up to the contemporary challenges posed by adoption and advancement of globally driven millennium development goals (MDGs), public medical centers (PMCs) cannot afford to be reckoned with financial epilepsy, bankruptcy, and degeneracy. This concern informed the thrust of the study. In the process, pertinent research questions were posed which elicited corresponding hypothetical propositions. With primary data volunteered by 150 administrative officials drawn from PMCs across the country, analytical proceedings were facilitated by the application of chi-square (x2) technique. The findings brought to the fore, the general bad shape of cash management in PMCs in the country. The recommendations for urgent attention underscored the constitution of strategic budget communities (SBCs), revitalization of internal audit committees (IACs), and attraction of goodwill private-sector endowments through convincing justification of the utilization and optimization of current government logistic subventions.

  20. Revitalizing sociology: urban life and mental illness between history and the present.

    PubMed

    Fitzgerald, Des; Rose, Nikolas; Singh, Ilina

    2016-03-01

    This paper proposes a re-thinking of the relationship between sociology and the biological sciences. Tracing lines of connection between the history of sociology and the contemporary landscape of biology, the paper argues for a reconfiguration of this relationship beyond popular rhetorics of 'biologization' or 'medicalization'. At the heart of the paper is a claim that, today, there are some potent new frames for re-imagining the traffic between sociological and biological research - even for 'revitalizing' the sociological enterprise as such. The paper threads this argument through one empirical case: the relationship between urban life and mental illness. In its first section, it shows how this relationship enlivened both early psychiatric epidemiology, and some forms of the new discipline of sociology; it then traces the historical division of these sciences, as the sociological investment in psychiatric questions waned, and 'the social' become marginalized within an increasingly 'biological' psychiatry. In its third section, however, the paper shows how this relationship has lately been revivified, but now by a nuanced epigenetic and neurobiological attention to the links between mental health and urban life. What role can sociology play here? In its final section, the paper shows how this older sociology, with its lively interest in the psychiatric and neurobiological vicissitudes of urban social life, can be our guide in helping to identify intersections between sociological and biological attention. With a new century now underway, the paper concludes by suggesting that the relationship between urban life and mental illness may prove a core testing-ground for a 'revitalized' sociology.

  1. A model of the mechanisms of language extinction and revitalization strategies to save endangered languages.

    PubMed

    Fernando, Chrisantha; Valijärvi, Riitta-Liisa; Goldstein, Richard A

    2010-02-01

    Why and how have languages died out? We have devised a mathematical model to help us understand how languages go extinct. We use the model to ask whether language extinction can be prevented in the future and why it may have occurred in the past. A growing number of mathematical models of language dynamics have been developed to study the conditions for language coexistence and death, yet their phenomenological approach compromises their ability to influence language revitalization policy. In contrast, here we model the mechanisms underlying language competition and look at how these mechanisms are influenced by specific language revitalization interventions, namely, private interventions to raise the status of the language and thus promote language learning at home, public interventions to increase the use of the minority language, and explicit teaching of the minority language in schools. Our model reveals that it is possible to preserve a minority language but that continued long-term interventions will likely be necessary. We identify the parameters that determine which interventions work best under certain linguistic and societal circumstances. In this way the efficacy of interventions of various types can be identified and predicted. Although there are qualitative arguments for these parameter values (e.g., the responsiveness of children to learning a language as a function of the proportion of conversations heard in that language, the relative importance of conversations heard in the family and elsewhere, and the amplification of spoken to heard conversations of the high-status language because of the media), extensive quantitative data are lacking in this field. We propose a way to measure these parameters, allowing our model, as well as others models in the field, to be validated.

  2. Digital ac monitor

    DOEpatents

    Hart, George W.; Kern, Jr., Edward C.

    1987-06-09

    An apparatus and method is provided for monitoring a plurality of analog ac circuits by sampling the voltage and current waveform in each circuit at predetermined intervals, converting the analog current and voltage samples to digital format, storing the digitized current and voltage samples and using the stored digitized current and voltage samples to calculate a variety of electrical parameters; some of which are derived from the stored samples. The non-derived quantities are repeatedly calculated and stored over many separate cycles then averaged. The derived quantities are then calculated at the end of an averaging period. This produces a more accurate reading, especially when averaging over a period in which the power varies over a wide dynamic range. Frequency is measured by timing three cycles of the voltage waveform using the upward zero crossover point as a starting point for a digital timer.

  3. Digital ac monitor

    DOEpatents

    Hart, G.W.; Kern, E.C. Jr.

    1987-06-09

    An apparatus and method is provided for monitoring a plurality of analog ac circuits by sampling the voltage and current waveform in each circuit at predetermined intervals, converting the analog current and voltage samples to digital format, storing the digitized current and voltage samples and using the stored digitized current and voltage samples to calculate a variety of electrical parameters; some of which are derived from the stored samples. The non-derived quantities are repeatedly calculated and stored over many separate cycles then averaged. The derived quantities are then calculated at the end of an averaging period. This produces a more accurate reading, especially when averaging over a period in which the power varies over a wide dynamic range. Frequency is measured by timing three cycles of the voltage waveform using the upward zero crossover point as a starting point for a digital timer. 24 figs.

  4. Cooling Floor AC Systems

    NASA Astrophysics Data System (ADS)

    Jun, Lu; Hao, Ding; Hong, Zhang; Ce, Gao Dian

    The present HVAC equipments for the residential buildings in the Hot-summer-and-Cold-winter climate region are still at a high energy consuming level. So that the high efficiency HVAC system is an urgently need for achieving the preset government energy saving goal. With its advantage of highly sanitary, highly comfortable and uniform of temperature field, the hot-water resource floor radiation heating system has been widely accepted. This paper has put forward a new way in air-conditioning, which combines the fresh-air supply unit and such floor radiation system for the dehumidification and cooling in summer or heating in winter. By analyze its advantages and limitations, we found that this so called Cooling/ Heating Floor AC System can improve the IAQ of residential building while keep high efficiency quality. We also recommend a methodology for the HVAC system designing, which will ensure the reduction of energy cost of users.

  5. Automated ac galvanomagnetic measurement system

    NASA Technical Reports Server (NTRS)

    Szofran, F. R.; Espy, P. N.

    1985-01-01

    An automated, ac galvanomagnetic measurement system is described. Hall or van der Pauw measurements in the temperature range 10-300 K can be made at a preselected magnetic field without operator attendance. Procedures to validate sample installation and correct operation of other system functions, such as magnetic field and thermometry, are included. Advantages of ac measurements are discussed.

  6. Management of the Atmosphere Resource Recovery and Environmental Monitoring Project

    NASA Technical Reports Server (NTRS)

    Roman, Monsi; Perry, Jay; Howard, David

    2013-01-01

    The Advanced Exploration Systems Program's Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project is working to further optimize atmosphere revitalization and environmental monitoring system architectures. This paper discusses project management strategies that tap into skill sets across multiple engineering disciplines, projects, field centers, and industry to achieve the project success. It is the project's objective to contribute to system advances that will enable sustained exploration missions beyond Lower Earth Orbit (LEO) and improve affordability by focusing on the primary goals of achieving high reliability, improving efficiency, and reducing dependence on ground-based logistics resupply. Technology demonstrations are achieved by infusing new technologies and concepts with existing developmental hardware and operating in a controlled environment simulating various crewed habitat scenarios. The ARREM project's strengths include access to a vast array of existing developmental hardware that perform all the vital atmosphere revitalization functions, exceptional test facilities to fully evaluate system performance, and a well-coordinated partnering effort among the NASA field centers and industry partners to provide the innovative expertise necessary to succeed.

  7. Performance Evaluation of Engineered Structured Sorbents for Atmosphere Revitalization Systems On Board Crewed Space Vehicles and Habitats

    NASA Technical Reports Server (NTRS)

    Howard, David F.; Perry, Jay L.; Knox, James C.; Junaedi, Christian; Roychoudhury, Subir

    2011-01-01

    Engineered structured (ES) sorbents are being developed to meet the technical challenges of future crewed space exploration missions. ES sorbents offer the inherent performance and safety attributes of zeolite and other physical adsorbents but with greater structural integrity and process control to improve durability and efficiency over packed beds. ES sorbent techniques that are explored include thermally linked and pressure-swing adsorption beds for water-save dehumidification and sorbent-coated metal meshes for residual drying, trace contaminant control, and carbon dioxide control. Results from sub-scale performance evaluations of a thermally linked pressure-swing adsorbent bed and an integrated sub-scale ES sorbent system are discussed.

  8. Layoff Handling Still Lags ACS Standards.

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1981

    1981-01-01

    Reviews termination procedures of professional chemists and the compliance of these terminations to the American Chemical Society's (ACS's) Professional Employment Guidelines. Provides the ACS guidelines. (DS)

  9. AC photovoltaic module magnetic fields

    SciTech Connect

    Jennings, C.; Chang, G.J.; Reyes, A.B.; Whitaker, C.M.

    1997-12-31

    Implementation of alternating current (AC) photovoltaic (PV) modules, particularly for distributed applications such as PV rooftops and facades, may be slowed by public concern about electric and magnetic fields (EMF). This paper documents magnetic field measurements on an AC PV module, complementing EMF research on direct-current PV modules conducted by PG and E in 1993. Although not comprehensive, the PV EMF data indicate that 60 Hz magnetic fields (the EMF type of greatest public concern) from PV modules are comparable to, or significantly less than, those from household appliances. Given the present EMF research knowledge, AC PV module EMF may not merit considerable concern.

  10. Development and Testing of a Temperature-swing Adsorption Compressor for Carbon Dioxide in Closed-loop Air Revitalization Systems

    NASA Technical Reports Server (NTRS)

    Mulloth, Lila M.; Rosen, Micha; Affleck, David; LeVan, M. Douglas; Wang, Yuan

    2005-01-01

    The air revitalization system of the International Space Station (ISS) operates in an open loop mode and relies on the resupply of oxygen and other consumables from earth for the life support of astronauts. A compressor is required for delivering the carbon dioxide from a removal assembly to a reduction unit to recover oxygen and thereby dosing the air-loop. We have developed a temperature-swing adsorption compressor (TSAC) that is energy efficient, quiet, and has no rapidly moving parts for performing these tasks. The TSAC is a solid-state compressor that has the capability to remove CO2 from a low- pressure source, and subsequently store, compress, and deliver at a higher pressure as required by a processor. The TSAC is an ideal interface device for CO2 removal and reduction units in the air revitalization loop of a spacecraft for oxygen recovery. This paper discusses the design and testing of a TSAC for carbon dioxide that has application in the ISS and future spacecraft for closing the air revitalization loop.

  11. Application of Vacuum Swing Adsorption for Carbon Dioxide and Water Vapor Removal from Manned Spacecraft Atmospheres

    NASA Technical Reports Server (NTRS)

    Knox, J.; Fulda, P.; Howard, D.; Ritter, J.; Levan, M.

    2007-01-01

    The design and testing of a vacuum-swing adsorption process to remove metabolic 'water and carbon dioxide gases from NASA's Orion crew exploration vehicle atmosphere is presented. For the Orion spacecraft, the sorbent-based atmosphere revitalization (SBAR) system must remove all metabolic water, a technology approach 1Lhathas not been used in previous spacecraft life support systems. Design and testing of a prototype SBAR in sub-scale and full-scale configurations is discussed. Experimental and analytical investigations of dual-ended and single-ended vacuum desorption are presented. An experimental investigation of thermal linking between adsorbing and desorbing columns is also presented.

  12. Atmospheric Composition Data and Information Services Center (ACDISC)

    NASA Technical Reports Server (NTRS)

    Kempler, S.

    2005-01-01

    NASA's GSFC Earth Sciences (GES) Data and Information and Data Services Center (DISC) manages the archive, distribution and data access for atmospheric composition data from AURA'S OMI, MLS, and hopefully one day, HIRDLS instruments, as well as heritage datasets from TOMS, UARS, MODIS, and AIRS. This data is currently archived in the GES Distributed Active Archive Center (DAAC). The GES DISC has begun the development of a community driven data management system that's sole purpose is to manage and provide value added services to NASA's Atmospheric Composition (AC) Data. This system, called the Atmospheric Composition Data and Information Services Center (ACDISC) will provide access all AC datasets from the above mentioned instruments, as well as AC datasets residing at remote archive sites (e.g, LaRC DAAC) The goals of the ACDISC are to: 1) Provide a data center for Atmospheric Scientists, guided by Atmospheric Scientists; 2) Be absolutely responsive to the data and data service needs of the Atmospheric Composition (AC) community; 3) Provide services (i.e., expertise) that will facilitate the effortless access to and usage of AC data; 4) Collaborate with AC scientists to facilitate the use of data from multiple sensors for long term atmospheric research. The ACDISC is an AC specific, user driven, multi-sensor, on-line, easy access archive and distribution system employing data analysis and visualization, data mining, and other user requested techniques that facilitate science data usage. The purpose of this presentation is to provide the evolution path that the GES DISC in order to better serve AC data, and also to receive continued community feedback and further foster collaboration with AC data users and providers.

  13. The revitalization of health and education in Rural America Act of 1992

    NASA Technical Reports Server (NTRS)

    English, Glenn

    1991-01-01

    During the preceding decade of the 1980's, rural communities witnessed an exodus of over 5 million residents to urban and suburban areas of the nation. It has become increasingly clear that rural parts of the country must adopt aggressive strategies to strengthen rural communities and enhance the quality of life for its citizens into the 21st century. Studies by the U.S. Department of Commerce, Office of Technology Assessment, and the Aspen Institute all identify advanced telecommunications systems as the linchpin for a vigorous future for rural America. The Revitalization of Health and Education in Rural America Act of 1992 incorporates these recommendations into viable strategies to improve health care and educational services for rural citizens. By linking up hospitals and schools through advanced telecommunications technology, vast geographic distances are instantly reduced. With the proper infrastructure in place, up-to-date telecommunications services will facilitate endless opportunities for improving the quality of life in remote areas. This comprehensive legislation is the critical first step in forging a partnership with urban communities to create an economically sound and technologically advanced America for generations to come. Improvement of health care and educational services in rural areas through the implementation of interactive telecommunications systems is addressed. A copy of the Act is included.

  14. Norwegian public health policy: revitalization of the social democratic welfare state?

    PubMed

    Fosse, Elisabeth

    2009-01-01

    Norway is part of the so-called social democratic welfare state model, which is characterized by its emphasis on solidarity and redistribution among social groups. The concepts of upstream and downstream policy measures may be useful to characterize different approaches to public health policies: upstream measures would be structural measures, in line with the social democratic welfare state model, while downstream measures would be more targeted at individuals or groups at some sort of risk. The aim of this article is to analyze national policies in Norway and how these may be characterized in terms of upstream and downstream factors. Health promotion and public health policies have been high on the Norwegian political agenda for two decades. However, the national policy emphasis has shifted between strategies aimed at individuals and structural strategies--that is, between downstream and upstream measures. Until 2003, policies included mainly downstream measures, but since then a policy shift has taken place and current policy includes an emphasis on upstream measures. This policy was strengthened after a left-wing coalition came into government in 2005. It may be argued that the present policy represents a revitalization of universal and structural measures, in line with the social democratic welfare state model.

  15. Partnership for the Revitalization of National Wind Tunnel Force Measurement Capability

    NASA Technical Reports Server (NTRS)

    Rhew, Ray D.; Skelley, Marcus L.; Woike, Mark R.; Bader, Jon B.; Marshall, Timothy J.

    2009-01-01

    Lack of funding and lack of focus on research over the past several years, coupled with force measurement capabilities being decentralized and distributed across the National Aeronautics and Space Administration (NASA) research centers, has resulted in a significant erosion of (1) capability and infrastructure to produce and calibrate force measurement systems; (2) NASA s working knowledge of those systems; and (3) the quantity of high-quality, full-capability force measurement systems available for use in aeronautics testing. Simultaneously, and at proportional rates, the capability of industry to design, manufacture, and calibrate these test instruments has been eroding primarily because of a lack of investment by the aeronautics community. Technical expertise in this technology area is a core competency in aeronautics testing; it is highly specialized and experience-based, and it represents a niche market for only a few small precision instrument shops in the United States. With this backdrop, NASA s Aeronautics Test Program (ATP) chartered a team to examine the issues and risks associated with the problem, focusing specifically on strain- gage balances. The team partnered with the U.S. Air Force s Arnold Engineering Development Center (AEDC) to exploit their combined capabilities and take a national level government view of the problem. This paper describes the team s approach, its findings, and its recommendations, and the current status for revitalizing the government s balance capability with respect to designing, fabricating, calibrating, and using the instruments.

  16. NONLINEAR DIAGNOSTICS USING AC DIPOLES.

    SciTech Connect

    PEGGS,S.

    1999-03-29

    There are three goals in the accurate nonlinear diagnosis of a storage ring. First, the beam must be moved to amplitudes many times the natural beam size. Second, strong and long lasting signals must be generated. Third, the measurement technique should be non-destructive. Conventionally, a single turn kick moves the beam to large amplitudes, and turn-by-turn data are recorded from multiple beam position monitors (BPMs) [1-6]. Unfortunately, tune spread across the beam causes the center of charge beam signal to ''decohere'' on a time scale often less than 100 turns. Filamentation also permanently destroys the beam emittance (in a hadron ring). Thus, the ''strong single turn kick'' technique successfully achieves only one out of the three goals. AC dipole techniques can achieve all three. Adiabatically excited AC dipoles slowly move the beam out to large amplitudes. The coherent signals then recorded last arbitrarily long. The beam maintains its original emittance if the AC dipoles are also turned off adiabatically, ready for further use. The AGS already uses an RF dipole to accelerate polarized proton beams through depolarizing resonances with minimal polarization loss [7]. Similar AC dipoles will be installed in the horizontal and vertical planes of both rings in RHIC [8]. The RHIC AC dipoles will also be used as spin flippers, and to measure linear optical functions [9].

  17. Native Skywatchers - Revitalization of Ojibwe & D(L)akota Star Knowledge - Collaborative Work with Educators

    NASA Astrophysics Data System (ADS)

    Lee, Annette S.; Gawboy, Carl; Rock, Jim; Tibbetts, Jeff; Wilson, William; O'Rourke, Charlene

    2015-08-01

    In Ojibwe culture we look towards the Evening Star and honor Ikwe’ Anung - the Woman’s Star. In D(L)akota culture in addition to seeing the dragon, Draco in the northern circumpolar skies, we recognize Wakiyan - the Thunderbird, located at the center of the precession circle. Woven into the native star knowledge are important and insightful understandings of astronomical patterns and phenomenon that are too valuable to be forgotten. This living relationship with the cosmos is a core part of the cultural history and present day heritage of native people.Native Skywatchers is an indigenous led initiative to revitalize and rebuild the star knowledge of the Ojibwe and D(L)akota peoples. Right now is a critical time; much has been lost. At the same time, there is a tremendous demand and excitement for this knowledge.Growing momentum is due in part to the MN State K-12 Science Standards (2009) that requires educators to teach how: “Men and women throughout the history of all cultures, including Minnesota American Indian tribes and communities, have been involved in engineering design and scientific inquiry.” Specifically Benchmark 3.1.3.2.1 states, “For example: Ojibwe and Dakota knowledge and use of patterns in the stars to predict and plan”.This important work has many branches: interdisciplinary connections in science and culture, formal and informal science education, artwork and art programming, history and heritage, outreach and community wellness.The focus of this presentation will be collaborative work done with educators. The aim has been expanding the work from cultural heritage into classroom curriculum while preserving the cultural integrity. This has been accomplished by two primary factors: 1.) the development of resources such as: native star maps, planispheres, constellation guidebooks, artwork, curriculum; 2.) dissemination and exchange with regional educators, including the state office of the Minnesota Department of Education.

  18. A Multifaceted Approach to Revitalizing the Baby-Friendly Hospital Initiative in Croatia.

    PubMed

    Grgurić, Josip; Zakarija-Grković, Irena; Pavičić Bošnjak, Anita; Stanojević, Milan

    2016-08-01

    The Baby-Friendly Hospital Initiative (BFHI) was launched in Croatia in 1993. By 1998, 15 of 34 maternity facilities were designated "Baby-Friendly." Introduction of hospital bags, violating the International Code of the Marketing of Breastmilk Substitutes, led to a standstill in the BFHI. The aim of this article is to describe the successful reintroduction of the BFHI in Croatia between 2007 and 2015. After hospital bags were abolished in 2007, UNICEF Croatia undertook an assessment of BFHI implementation. All maternity facilities were invited by UNICEF and the Ministry of Health to join the renewed BFHI. UNICEF materials were translated and training for trainers, assessors, coordinators, and hospital staff held. By June 2015, 30 of 32 (94%) maternity facilities, providing care to 89% of newborns, were Baby-Friendly. Nine maternity hospitals have been renovated and 2 new hospitals have been built. Exclusive breastfeeding rates have risen 16% at 0 to 2 months (from 51% in 2007 to 67% in 2014) and 14% at 3 to 5 months (from 32% in 2007 to 46% in 2014). Fourteen "Breastfeeding-Friendly" primary care practices have been designated, 166 breastfeeding support groups are in operation, criteria for Mother-Friendly care are being piloted in 2 maternity facilities, and "Ten Steps in the Neonatal Intensive Care Unit" are being introduced. The BFHI provides an excellent opportunity for revitalizing breastfeeding protection, promotion, and support in all settings. Recognition and support of the BFHI by the Croatian government was crucial for implementing the BFHI, whereas the marketing practices of the breast milk substitutes industry are an ongoing challenge.

  19. Revitalization of clinical skills training at the University of the Western Cape.

    PubMed

    Jeggels, J D; Traut, A; Kwast, M

    2010-06-01

    Most educational institutions that offer health related qualifications make use of clinical skills laboratories. These spaces are generally used for the demonstration and assessment of clinical skills. The purpose of this paper is to share our experiences related to the revitalization of skills training by introducing the skills lab method at the School of Nursing (SoN), University of the Western Cape (UWC). To accommodate the contextual changes as a result of the restructuring of the higher education landscape in 2003, the clinical skills training programme at UWC had to be reviewed. With a dramatic increase in the student numbers and a reduction in hospital beds, the skills lab method provided students with an opportunity to develop clinical skills prior to their placement in real service settings. The design phase centred on adopting a skills training methodology that articulates with the case-based approach used by the SoN. Kolb's, experiential learning cycle provided the theoretical underpinning for the methodology. The planning phase was spent on the development of resources. Eight staff members were trained by our international higher education collaborators who also facilitated the training of clinical supervisors and simulated patients. The physical space had to be redesigned to accommodate audio visual and information technology to support the phases of the skills lab method. The implementation of the skills lab method was phased in from the first-year level. An interactive seminar held after the first year of implementation provided feedback from all the role players and was mostly positive. The results of introducing the skills lab method include: a move by students towards self-directed clinical skills development, clinical supervisors adopting the role of facilitators of learning and experiential clinical learning being based on, amongst others, the students' engagement with simulated patients. Finally, the recommendations relate to tailor

  20. Planetary atmospheres

    NASA Technical Reports Server (NTRS)

    Ingersoll, A. P.; Dobrovolskis, A. R.; Jakosky, B. M.

    1979-01-01

    The present paper deals with some of the principal data on extraterrestrial atmospheres obtained during the period 1975-1978. The atmospheres of Venus, Mars, Jupiter, and the Jovian satellites are examined, showing that many first-order questions concerning composition, physical state, and kinematics of these atmospheres have been answered.

  1. Air-Cooled Design of a Temperature-Swing Adsorption Compressor for Closed-Loop Air Revitalization Systems

    NASA Technical Reports Server (NTRS)

    Mulloth, Lila M.; Affleck, Dave L.; Rosen, Micha; LeVan, M. Douglas; Wang, Yuan; Cavalcante, Celio L.

    2004-01-01

    The air revitalization system of the International Space Station (ISS) operates in an open loop mode and relies on the resupply of oxygen and other consumables from earth for the life support of astronauts. A compressor is required for delivering the carbon dioxide from a removal assembly to a reduction unit to recover oxygen and thereby closing the air-loop. We have a developed a temperature-swing adsorption compressor (TSAC) for performing these tasks that is energy efficient, quiet, and has no rapidly moving parts. This paper discusses the mechanical design and the results of thermal model validation tests of a TSAC that uses air as the cooling medium.

  2. Revitalization of an Immature Permanent Mandibular Molar with a Necrotic Pulp Using Platelet-Rich Fibrin: A Case Report

    PubMed Central

    Shoba, Krishnamma; Aman, Shibu; Bharkavi, Srinivasan Kumar Indu

    2016-01-01

    Any insult to the pulp during its development causes cessation of dentin formation and root growth. Pulpal status and degree of root development are the decisive factors in the treatment approach. Various treatment options have been tried like surgery with root-end sealing, calcium hydroxide–apexification, placement of apical plug and regenerative endodontic procedures to induce apexogenesis. An ideal scenario for a necrosed tooth with immature root would be continued root development coupled with regeneration of pulp tissue. We report a case, where revitalization was done using Platelet-Rich Fibrin (PRF) as a scaffold in immature mandibular molar tooth. PMID:28050518

  3. ACS from development to operations

    NASA Astrophysics Data System (ADS)

    Caproni, Alessandro; Colomer, Pau; Jeram, Bogdan; Sommer, Heiko; Chiozzi, Gianluca; Mañas, Miguel M.

    2016-08-01

    The ALMA Common Software (ACS), provides the infrastructure of the distributed software system of ALMA and other projects. ACS, built on top of CORBA and Data Distribution Service (DDS) middleware, is based on a Component- Container paradigm and hides the complexity of the middleware allowing the developer to focus on domain specific issues. The transition of the ALMA observatory from construction to operations brings with it that ACS effort focuses primarily on scalability, stability and robustness rather than on new features. The transition came together with a shorter release cycle and a more extensive testing. For scalability, the most problematic area has been the CORBA notification service, used to implement the publisher subscriber pattern because of the asynchronous nature of the paradigm: a lot of effort has been spent to improve its stability and recovery from run time errors. The original bulk data mechanism, implemented using the CORBA Audio/Video Streaming Service, showed its limitations and has been replaced with a more performant and scalable DDS implementation. Operational needs showed soon the difference between releases cycles for Online software (i.e. used during observations) and Offline software, which requires much more frequent releases. This paper attempts to describe the impact the transition from construction to operations had on ACS, the solution adopted so far and a look into future evolution.

  4. Simple Equipment for Imaging AC.

    ERIC Educational Resources Information Center

    Kamata, Masahiro; Anayama, Takayuki

    2003-01-01

    Presents an effective way to demonstrate the difference between direct current and alternating current using red and green LEDs. Describes how to make a tool that shows how an AC voltage changes with time using the afterimage effect of the LEDs. (Author/NB)

  5. Laser Remote Sensing of Atmospheric Pollutants.

    DTIC Science & Technology

    1984-09-30

    of Cross-Correlation and Signal Averaging Appendix B: Laser Remote Sensing of Atmospheric Ammonia using a 33 C02 LIDAR System Ac-’,i- n For AVE...of CO2 differential-absorption LIDAR (DIAL) for the remote sensing of atmospheric pollutants was continued during FY84 and consisted of two...individual LIDAR signals and then taking the ratios of the averaged signals in order to deduce the differential-absorption value. This is in contrast to

  6. Atmospheric neutrons

    NASA Technical Reports Server (NTRS)

    Korff, S. A.; Mendell, R. B.; Merker, M.; Light, E. S.; Verschell, H. J.; Sandie, W. S.

    1979-01-01

    Contributions to fast neutron measurements in the atmosphere are outlined. The results of a calculation to determine the production, distribution and final disappearance of atmospheric neutrons over the entire spectrum are presented. An attempt is made to answer questions that relate to processes such as neutron escape from the atmosphere and C-14 production. In addition, since variations of secondary neutrons can be related to variations in the primary radiation, comment on the modulation of both radiation components is made.

  7. ac-resistance-measuring instrument

    SciTech Connect

    Hof, P.J.

    1981-04-22

    An auto-ranging ac resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an ac excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance.

  8. Simultaneous distribution of AC and DC power

    DOEpatents

    Polese, Luigi Gentile

    2015-09-15

    A system and method for the transport and distribution of both AC (alternating current) power and DC (direct current) power over wiring infrastructure normally used for distributing AC power only, for example, residential and/or commercial buildings' electrical wires is disclosed and taught. The system and method permits the combining of AC and DC power sources and the simultaneous distribution of the resulting power over the same wiring. At the utilization site a complementary device permits the separation of the DC power from the AC power and their reconstruction, for use in conventional AC-only and DC-only devices.

  9. A Narrative Inquiry of Technology as a Viable Support to Revitalizing and Increasing the Choctaw Language among American Indians and Non-Indians in an Early Childhood Setting

    ERIC Educational Resources Information Center

    McClour, Christine Elizabeth

    2015-01-01

    In the past several decades the global village has witnessed a rapid decline in the number of indigenous languages. This study was a narrative inquiry within a qualitative methodology. Two research questions were used to analyze the narratives of Choctaw Nation Head Start teachers concerning technology usage for increasing, and revitalizing the…

  10. US-German Cooperation For Further Development Of Decision Support Systems For Sustainable Contaminated Site Revitalization - Berlin, Germany, Sept. 24, 2008.

    EPA Science Inventory

    SMARTe (Sustainable Management Approaches and Revitalization Tools - electronic) is a web-based decision support tool developed by the Office of Research and Development (ORD) in partnership with the Office of Brownfields and Land Revital...

  11. Atmospheric chemistry

    SciTech Connect

    Sloane, C.S. ); Tesche, T.W. )

    1991-01-01

    This book covers the predictive strength of atmospheric models. The book covers all of the major important atmospheric areas, including large scale models for ozone depletion and global warming, regional scale models for urban smog (ozone and visibility impairment) and acid rain, as well as accompanying models of cloud processes and biofeedbacks.

  12. Lessons Learned from the Development and Implementation of the Atmosphere Resource Recovery and Environmental Monitoring Project

    NASA Technical Reports Server (NTRS)

    Roman, Monsi C.; Perry, Jay L.; Howard, David F.

    2014-01-01

    The Advanced Exploration Systems (AES) Program's Atmosphere Resource Recovery and Environmental Monitoring (ARREM) Project have been developing atmosphere revitalization and environmental monitoring subsystem architectures suitable for enabling sustained crewed exploration missions beyond low Earth orbit (LEO). Using the International Space Station state-of-the-art (SOA) as the technical basis, the ARREM Project has contributed to technical advances that improve affordability, reliability, and functional efficiency while reducing dependence on a ground-based logistics resupply model. Functional demonstrations have merged new process technologies and concepts with existing ISS developmental hardware and operate them in a controlled environment simulating various crew metabolic loads. The ARREM Project's strengths include access to a full complement of existing developmental hardware that perform all the core atmosphere revitalization functions, unique testing facilities to evaluate subsystem performance, and a coordinated partnering effort among six NASA field centers and industry partners to provide the innovative expertise necessary to succeed. A project overview is provided and the project management strategies that have enabled a multidiscipinary engineering team to work efficiently across project, NASA field center, and industry boundaries to achieve the project's technical goals are discussed. Lessons learned and best practices relating to the project are presented and discussed.

  13. Atmospheric composition

    NASA Technical Reports Server (NTRS)

    Daniels, G. E.

    1973-01-01

    The earth's atmosphere is made up of a number of gases in different relative amounts. Near sea level and up to about 90 km, the amount of these atmospheric gases in clean, relatively dry air is practically constant. Four of these gases, nitrogen, oxygen, argon, and carbon dioxide, make up 99.99 percent by volume of the atmosphere. Two gases, ozone and water vapor, change in relative amounts, but the total amount of these two is very small compared to the amount of the other gases. The atmospheric composition shown in a table can be considered valid up to 90 km geometric altitude. Above 90 km, mainly because of molecular dissociation and diffusive separation, the composition changes.

  14. Effect of the magnetic material on AC losses in HTS conductors in AC magnetic field carrying AC transport current

    NASA Astrophysics Data System (ADS)

    Wan, Xing-Xing; Huang, Chen-Guang; Yong, Hua-Dong; Zhou, You-He

    2015-11-01

    This paper presents an investigation on the AC losses in several typical superconducting composite conductors using the H-formulation model. A single superconducting strip with ferromagnetic substrate or cores and a stack of coated conductors with ferromagnetic substrates are studied. We consider all the coated conductors carrying AC transport currents and simultaneously exposed to perpendicular AC magnetic fields. The influences of the amplitude, frequency, phase difference and ferromagnetic materials on the AC losses are investigated. The results show that the magnetization losses of single strip and stacked strips have similar characteristics. The ferromagnetic substrate can increase the magnetization loss at low magnetic field, and decrease the loss at high magnetic field. The ferromagnetic substrate can obviously increase the transport loss in stacked strips. The trends of total AC losses of single strip and stacked strips are similar when they are carrying current or exposed to a perpendicular magnetic field. The effect of the frequency on the total AC losses of single strip is related to the amplitude of magnetic field. The AC losses decrease with increasing frequency in low magnetic field region while increase in high magnetic field region. As the phase difference changes, there is a periodic variation for the AC losses. Moreover, when the strip is under only the transport current and magnetic field, the ferromagnetic cores will increase the AC losses for large transport current or field.

  15. Atmospheric pollution

    SciTech Connect

    Pickett, E.E.

    1987-01-01

    Atmospheric pollution (AP), its causes, and measures to prevent or reduce it are examined in reviews and reports presented at a workshop held in Damascus, Syria in August 1985. Topics discussed include AP and planning studies, emission sources, pollutant formation and transformation, AP effects on man and vegetation, AP control, atmospheric dispersion mechanisms and modeling, sampling and analysis techniques, air-quality monitoring, and applications. Diagrams, graphs, and tables of numerical data are provided.

  16. ac electroosmosis in rectangular microchannels.

    PubMed

    Campisi, Michele; Accoto, Dino; Dario, Paolo

    2005-11-22

    Motivated by the growing interest in ac electroosmosis as a reliable no moving parts strategy to control fluid motion in microfluidic devices for biomedical applications, such as lab-on-a-chip, we study transient and steady-state electrokinetic phenomena (electroosmosis and streaming currents) in infinitely extended rectangular charged microchannels. With the aid of Fourier series and Laplace transforms we provide a general formal solution of the problem, which is used to study the time-dependent response to sudden ac applied voltage differences in case of finite electric double layer. The Debye-Huckel approximation has been adopted to allow for an algebraic solution of the Poisson-Boltzmann problem in Fourier space. We obtain the expressions of flow velocity profiles, flow rates, streaming currents, as well as expressions of the complex hydraulic and electrokinetic conductances. We analyze in detail the dependence of the electrokinetic conductance on the extension of linear dimensions relative to the Debye length, with an eye on finite electric double layer effects.

  17. ACS PSF Variations with Temperatures

    NASA Astrophysics Data System (ADS)

    Sahu, Kailash C.; Lallo, Matt; Makidon, Russ

    2007-09-01

    We have used the HST ACS/WFC observations of a Galactic bulge field taken over a continuous interval of 7 days (Prop 9750) to investigate the possible dependence of the ACS focus with the external temperatures. This dataset allows us to investigate possible focus variations over timescales of a few hours to a few days. The engineering data related to the external temperatures for this duration show that the maximum temperature change occurred over the first 1.5 days. Among all the different temperatures recorded, the truss diametric differential and the truss axial temperatures are the only two temperatures which have the same timescale of variation as the PSFwidth variations. The PSF-widths also strongly correlate with these two temperatures during this time interval. We empirically fit the PSF-width variations with these 2 temperature sensor values. This suggests that the focus has a similar dependence, and we recommend that this finding be followed up with the determination of actual focus values to check if the focus values indeed have the same correlation. If so, the temperature data can be useful in estimating the focus values, which can then be used to predict the PSFs to a first order.

  18. ac electroosmosis in rectangular microchannels

    NASA Astrophysics Data System (ADS)

    Campisi, Michele; Accoto, Dino; Dario, Paolo

    2005-11-01

    Motivated by the growing interest in ac electroosmosis as a reliable no moving parts strategy to control fluid motion in microfluidic devices for biomedical applications, such as lab-on-a-chip, we study transient and steady-state electrokinetic phenomena (electroosmosis and streaming currents) in infinitely extended rectangular charged microchannels. With the aid of Fourier series and Laplace transforms we provide a general formal solution of the problem, which is used to study the time-dependent response to sudden ac applied voltage differences in case of finite electric double layer. The Debye-Hückel approximation has been adopted to allow for an algebraic solution of the Poisson-Boltzmann problem in Fourier space. We obtain the expressions of flow velocity profiles, flow rates, streaming currents, as well as expressions of the complex hydraulic and electrokinetic conductances. We analyze in detail the dependence of the electrokinetic conductance on the extension of linear dimensions relative to the Debye length, with an eye on finite electric double layer effects.

  19. Revitalize the US silicon/ferrosilicon industry through energy-efficient technology. Part 1, Final report

    SciTech Connect

    Larson, H.R.; Welborn, J.H.

    1995-02-01

    It is concluded that silicon metal and ferrosilicon can be very effectively produced in a DC submerged arc furnace. Specific energy consumption factors measured were favorable to the technology. Significant energy savings over conventional AC practice are likely. Hollow electrode feeding of the furnace does not appear feasible. Electrode consumption was 0.144 lbs/lb so silicon while making metal, much of which occurred above the burden pile. Silicon loss to fume averaged 19.5% of the silicon charge. In this furnace, 50% FeSi was more difficult to produce than silicon metal, and the furnace could not be run with full burden; it was operated successfully about 3/4 full. In the silicon metal portion, the furnace was operated in a fully submerged mode for several 3-day test campaigns. The industry must seriously consider the identified benefits of DC plasma arc technology for retrofit or new added silicon capacity.

  20. RHIC spin flipper AC dipole controller

    SciTech Connect

    Oddo, P.; Bai, M.; Dawson, C.; Gassner, D.; Harvey, M.; Hayes, T.; Mernick, K.; Minty, M.; Roser, T.; Severino, F.; Smith, K.

    2011-03-28

    The RHIC Spin Flipper's five high-Q AC dipoles which are driven by a swept frequency waveform require precise control of phase and amplitude during the sweep. This control is achieved using FPGA based feedback controllers. Multiple feedback loops are used to and dynamically tune the magnets. The current implementation and results will be presented. Work on a new spin flipper for RHIC (Relativistic Heavy Ion Collider) incorporating multiple dynamically tuned high-Q AC-dipoles has been developed for RHIC spin-physics experiments. A spin flipper is needed to cancel systematic errors by reversing the spin direction of the two colliding beams multiple times during a store. The spin flipper system consists of four DC-dipole magnets (spin rotators) and five AC-dipole magnets. Multiple AC-dipoles are needed to localize the driven coherent betatron oscillation inside the spin flipper. Operationally the AC-dipoles form two swept frequency bumps that minimize the effect of the AC-dipole dipoles outside of the spin flipper. Both AC bumps operate at the same frequency, but are phase shifted from each other. The AC-dipoles therefore require precise control over amplitude and phase making the implementation of the AC-dipole controller the central challenge.

  1. Regional Approach And Tools For Sustainable Revitalization, Documentation Of A Workshop Of The U.S.-German Bilateral Working Group, May 8 And 9, 2008 - New York, New York

    EPA Science Inventory

    There is growing international recognition that revitalization of regions containing potentially contaminated sites to meet economic, environmental/ecological, and social/cultural demands can and should contribute to the sustainability of the human and natural environment by impr...

  2. Atmospheric Photochemistry

    NASA Technical Reports Server (NTRS)

    Massey, Harrie; Potter, A. E.

    1961-01-01

    The upper atmosphere offers a vast photochemical laboratory free from solid surfaces, so all reactions take place in the gaseous phase. At 30 km altitude the pressure has fallen to about one-hundredth of that at ground level, and we shall, rather arbitrarily, regard the upper atmosphere as beginning at that height. By a little less than 100 km the pressure has fallen to 10(exp -3) mm Hg and is decreasing by a power of ten for every 15 km increase in altitude. Essentially we are concerned then with the photochemistry of a nitrogen-oxygen mixture under low-pressure conditions in which photo-ionization, as well as photodissociation, plays an important part. Account must also be taken of the presence of rare constituents, such as water vapour and its decomposition products, including particularly hydroxyl, oxides of carbon, methane and, strangely enough, sodium, lithium and calcium. Many curious and unfamiliar reactions occur in the upper atmosphere. Some of them are luminescent, causing the atmosphere to emit a dim light called the airglow. Others, between gaseous ions and neutral molecules, are almost a complete mystery at this time. Similar interesting phenomena must occur in other planetary atmospheres, and they might be predicted if sufficient chemical information were available.

  3. Atmospheric radiation

    SciTech Connect

    Harshvardhan, M.R. )

    1991-01-01

    Studies of atmospheric radiative processes are summarized for the period 1987-1990. Topics discussed include radiation modeling; clouds and radiation; radiative effects in dynamics and climate; radiation budget and aerosol effects; and gaseous absorption, particulate scattering and surface reflection. It is concluded that the key developments of the period are a defining of the radiative forcing to the climate system by trace gases and clouds, the recognition that cloud microphysics and morphology need to be incorporated not only into radiation models but also climate models, and the isolation of a few important unsolved theoretical problems in atmospheric radiation.

  4. Atmospheric Waves

    NASA Technical Reports Server (NTRS)

    2007-01-01

    With its Multispectral Visible Imaging Camera (MVIC), half of the Ralph instrument, New Horizons captured several pictures of mesoscale gravity waves in Jupiter's equatorial atmosphere. Buoyancy waves of this type are seen frequently on Earth - for example, they can be caused when air flows over a mountain and a regular cloud pattern forms downstream. In Jupiter's case there are no mountains, but if conditions in the atmosphere are just right, it is possible to form long trains of these small waves. The source of the wave excitation seems to lie deep in Jupiter's atmosphere, below the visible cloud layers at depths corresponding to pressures 10 times that at Earth's surface. The New Horizons measurements showed that the waves move about 100 meters per second faster than surrounding clouds; this is about 25% of the speed of sound on Earth and is much greater than current models of these waves predict. Scientists can 'read' the speed and patterns these waves to learn more about activity and stability in the atmospheric layers below.

  5. Atmospheric humidity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water vapor plays a critical role in earth's atmosphere. It helps to maintain a habitable surface temperature through absorption of outgoing longwave radiation, and it transfers trmendous amounts of energy from the tropics toward the poles by absorbing latent heat during evaporation and subsequently...

  6. Long-Duration Testing of a Temperature-Swing Adsorption Compressor for Carbon Dioxide for Closed-Loop Air Revitalization Systems

    NASA Technical Reports Server (NTRS)

    Rosen, Micha; Mulloth, Lila; Varghese, Mini

    2005-01-01

    This paper describes the results of long-duration testing of a temperature-swing adsorption compressor that has application in the International Space Station (ISS) and future spacecraft for closing the air revitalization loop. The air revitalization system of the ISS operates in an open loop mode and relies on the resupply of oxygen and other consumables from Earth for the life support of astronauts. A compressor is required for delivering the carbon dioxide from a removal assembly to a reduction unit to recover oxygen and thereby closing the air-loop. The TSAC is a solid-state compressor that has the capability to remove CO2 from a low-pressure source, and subsequently store, compress, and deliver at a higher pressure as required by a processor. The TSAC is an ideal interface device for CO2 removal and reduction units in the air revitalization loop of a spacecraft for oxygen recovery. The TSAC was developed and its operation was successfully verified in integration tests with the flight-like Carbon Dioxide Removal Assembly (CDRA) at Marshall Space Flight Center prior to the long-duration tests. Long-duration tests reveal the impacts of repeated thermal cycling on the compressor components and the adsorbent material.

  7. Planetary Atmospheres

    NASA Astrophysics Data System (ADS)

    Encrenaz, T.; Murdin, P.

    2000-11-01

    Planetary atmospheres are the external gaseous envelopes which surround the planets. In the case of the telluric planets, they represent only a negligible fraction of their mass, but they play an essential role in the energy balance between the surfaces and the Sun. In the case of the GIANT PLANETS, which are mostly gaseous, they account for a large fraction of their total mass and constitute the...

  8. Atmospheric Acoustics

    NASA Astrophysics Data System (ADS)

    Heimann, Dietrich; Schady, Arthur; Feng, Joseph

    This chapter deals with sound propagation in the atmosphere, which is an important link in the functional chain from noise emissions from aircraft, road and rail vehicles, and wind turbines to noise perception. The principle processes in outdoor sound propagation are explained. They include refraction, diffraction, and reflection. Two sound propagation models for scientific applications are briefly outlined. Finally, three illustrative applications and their results are discussed.

  9. Three phase AC motor controller

    DOEpatents

    Vuckovich, Michael; Wright, Maynard K.; Burkett, John P.

    1984-03-20

    A motor controller for a three phase AC motor (10) which is adapted to operate bidirectionally from signals received either from a computer (30) or a manual control (32). The controller is comprised of digital logic circuit means which implement a forward and reverse command signal channel (27, 29) for the application of power through the forward and reverse power switching relays (16, 18, 20, 22). The digital logic elements are cross coupled to prevent activation of both channels simultaneously and each includes a plugging circuit (65, 67) for stopping the motor upon the removal of control signal applied to one of the two channels (27, 29) for a direction of rotation desired. Each plugging circuit (65, 67) includes a one-shot pulse signal generator (88, 102) which outputs a single pulse signal of predetermined pulsewidth which is adapted to inhibit further operation of the application of power in the channel which is being activated and to apply a reversal command signal to the other channel which provides a reversed phase application of power to the motor for a period defined by the pulse-width output of the one-shot signal generator to plug the motor (10) which will then be inoperative until another rotational command signal is applied to either of the two channels.

  10. Oxidants and oxidation in the Earth's atmosphere

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The 1994 BOC Priestley Conference was held at Bucknell University in Lewisburg, Pennsylvania, from June 24 through June 27, 1994. This conference, managed by the American Chemical Society (ACS), was a joint celebration with the Royal Society of Chemistry (RSC) commemorating Joseph Priestley's arrival in the U.S. and his discovery of oxygen. The basic theme of the conference was 'Oxidants and Oxidation in the Earth's Atmosphere,' with a keynote lecture on the history of ozone. A distinguished group of U.S. and international atmospheric chemists addressed the issues dominating current research and policy agendas. Topics crucial to the atmospheric chemistry of global change and local and regional air pollution were discussed. The program for the conference included four technical sessions on the following topics: (1) Oxidative Fate of Atmospheric Pollutants; (2) Photochemical Smog and Ozone; (3) Stratospheric Ozone; and (4) Global Tropospheric Ozone.

  11. Memory effect in ac plasma displays

    NASA Astrophysics Data System (ADS)

    Szlenk, K.; Obuchowicz, E.

    1993-10-01

    The bistable or `memory' mode of operation of an ac plasma display panel is presented. The difference between dc and ac plasma panel operation from the point of view of memory function is discussed. The graphic ac plasma display with thin film Cr-Cu-Cr electrodes was developed in OBREP and its basic parameters are described. It consists of 36 X 59 picture elements, its outer dimensions are: 76 X 52 mm2 and the screen size is: 49 X 30 mm2. The different dielectric glass materials were applied as dielectric layers and the influence of the properties of these materials on display parameters and memory function was investigated.

  12. Superconductor coil geometry and ac losses

    NASA Technical Reports Server (NTRS)

    Pierce, T. V., Jr.; Zapata, R. N.

    1976-01-01

    An empirical relation is presented which allows simple computation of volume-averaged winding fields from central fields for coils of small rectangular cross sections. This relation suggests that, in certain applications, ac-loss minimization can be accomplished by use of low winding densities, provided that hysteresis losses are independent of winding density. The ac-loss measurements on coils wound of twisted multifilamentary composite superconductors show no significant dependence on ac losses on winding density, thus permitting the use of winding density as an independent design parameter in loss minimization.

  13. Exenatide: AC 2993, AC002993, AC2993A, exendin 4, LY2148568.

    PubMed

    2004-01-01

    Exenatide [AC002993, AC2993A, AC 2993, LY2148568, exendin 4], a glucagon-like peptide-1 (GLP-1) agonist, is a synthetic exendin 4 compound under development with Amylin Pharmaceuticals for the treatment of type 2 diabetes. Both exendin 4 and its analogue, exendin 3, are 39-amino acid peptides isolated from Heloderma horridum lizard venom that have different amino acids at positions 2 and 3, respectively. Exendins are able to stimulate insulin secretion in response to rising blood glucose levels, and modulate gastric emptying to slow the entry of ingested sugars into the bloodstream. Amylin Pharmaceuticals acquired exclusive patent rights for the two exendin compounds (exendin 3 and exendin 4) from the originator, Dr John Eng (Bronx, NY, US). On 20 September 2002, Amylin and Eli Lilly signed a collaborative agreement for the development and commercialisation of exenatide for type 2 diabetes. Under the terms of the agreement, Eli Lilly has paid Amylin a licensing fee of 80 million US dollars and bought Amylin's stock worth 30 million US dollars at 18.69 US dollars a share. After the initial payment, Eli Lilly will pay Amylin up to 85 US dollars million upon reaching certain milestones and also make an additional payment of up to 130 million US dollars upon global commercialisation of exenatide. Both companies will share the US development and commercialisation costs, while Eli Lilly will pick up up to 80% of development costs and all commercialisation costs outside the US. Amylin and Eli Lilly will equally share profit from sales in the US, while Eli Lilly will get 80% of the profit outside the US and Amylin will get the rest. This agreement has also enabled Amylin to train its sales force to co-promote Lilly's human growth hormone Humatrope. Alkermes will receive research and development funding and milestone payments, and also a combination of royalty payments and manufacturing fees based on product sales. Alkermes undertakes the responsibility for the development

  14. Atmospheric science

    NASA Technical Reports Server (NTRS)

    Hamill, Patrick; Ackerman, Thomas; Clarke, Antony; Goodman, Jindra; Levin, Zev; Tomasko, Martin; Toon, O. Brian; Whitten, Robert

    1987-01-01

    The following types of experiments for a proposed Space Station Microgravity Particle Research Facility are described: (1) growth of liquid water drop populations; (2) coalescence; (3) drop breakup; (4) breakup of freezing drops; (5) ice nucleation for large aerosols or bacteria; (6) scavenging of gases, for example, SO2 oxidation; (7) phoretic forces, i.e., thermophoresis versus diffusiophoresis; (8) Rayleigh bursting of drops; (9) charge separation due to collisions of rimed and unrimed ice; (10) charged drop dynamics; (11) growth of particles in other planetary atmospheres; and (12) freezing and liquid-liquid evaporation. The required capabilities and desired hardware for the facility are detailed.

  15. High School Teachers Win ACS Prizes

    NASA Astrophysics Data System (ADS)

    Editorial Staff, Jce

    2009-07-01

    William E. Snyder is the 2009 winner of the ACS Division of Chemical Education Central Region Award for Excellence in High School Teaching; Sally Mitchell is the winner of the 2009 James Bryant Conant Award in High School Chemistry Teaching.

  16. The AC-120: The advanced commercial transport

    NASA Technical Reports Server (NTRS)

    Duran, David; Griffin, Ernest; Mendoza, Saul; Nguyen, Son; Pickett, Tim; Noernberg, Clemm

    1993-01-01

    The main objective of this design was to fulfill a need for a new airplane to replace the aging 100 to 150 passenger, 1500 nautical mile range aircraft such as the Douglas DC9 and Boeing 737-100 airplanes. After researching the future aircraft market, conducting extensive trade studies, and analysis on different configurations, the AC-120 Advanced Commercial Transport final design was achieved. The AC-120's main design features include the incorporation of a three lifting surface configuration which is powered by two turboprop engines. The AC-120 is an economically sensitive aircraft which meets the new FM Stage Three noise requirements, and has lower NO(x) emissions than current turbofan powered airplanes. The AC-120 also improves on its contemporaries in passenger comfort, manufacturing, and operating cost.

  17. Three-phase-to-two-phase direct AC-AC converter with three leg structure

    NASA Astrophysics Data System (ADS)

    Kwak, S.-S.

    2014-05-01

    A three-phase-to-two-phase ac-ac converter is, along with a modulation strategy based on the space vector scheme, introduced to directly drive two-phase output ac systems with high input power quality. The converter is capable of synthesising two sinusoidal output voltages with variable output frequency and arbitrary magnitude in quadrature phase-shift as well as sinusoidal input currents.

  18. Phase protection system for ac power lines

    NASA Technical Reports Server (NTRS)

    Wong, W. J. (Inventor)

    1974-01-01

    The system described provides protection for phase sensitive loads from being or remaining connected to ac power lines whenever a phase reversal occurs. It comprises a solid state phase detection circuit, a dc power relay circuit, an ac-to-dc converter for energizing the relay circuit, and a bistable four terminal transducer coupled between the phase detection circuit and the power relay circuit, for controlling both circuits.

  19. Atmosphere composition monitor for space station and advanced missions application

    SciTech Connect

    Wynveen, R.A.; Powell, F.T.

    1987-01-01

    Long-term human occupation of extraterrestrial locations may soon become a reality. The National Aeronautics and Space Administration (NASA) has recently completed the definition and preliminary design of the low earth orbit (LEO) space station. They are now currently moving into the detailed design and fabrication phase of this space station and are also beginning to analyze the requirements of several future missions that have been identified. These missions include, for example, Lunar and Mars sorties, outposts, bases, and settlements. A requirement of both the LEO space station and future missions are environmental control and life support systems (ECLSS), which provide a comfortable environment for humans to live and work. The ECLSS consists of several major systems, including atmosphere revitalization system (ARS), atmosphere pressure and composition control system, temperature and humidity control system, water reclamation system, and waste management system. Each of these major systems is broken down into subsystems, assemblies, units, and instruments. Many requirements and design drivers are different for the ECLSS of the LEO space station and the identified advanced missions (e.g., longer mission duration). This paper discusses one of the ARS assemblies, the atmosphere composition monitor assembly (ACMA), being developed for the LEO space station and addresses differences that will exist for the ACMA of future missions.

  20. Microtubule alignment and manipulation using AC electrokinetics.

    PubMed

    Uppalapati, Maruti; Huang, Ying-Ming; Jackson, Thomas N; Hancock, William O

    2008-09-01

    The kinesin-microtubule system plays an important role in intracellular transport and is a model system for integrating biomotor-driven transport into microengineered devices. AC electrokinetics provides a novel tool for manipulating and organizing microtubules in solution, enabling new experimental geometries for investigating and controlling the interactions of microtubules and microtubule motors in vitro. By fabricating microelectrodes on glass substrates and generating AC electric fields across solutions of microtubules in low-ionic-strength buffers, bundles of microtubules are collected and aligned and the electrical properties of microtubules in solution are measured. The AC electric fields result in electro-osmotic flow, electrothermal flow, and dielectrophoresis of microtubules, which can be controlled by varying the solution conductivity, AC frequency, and electrode geometry. By mapping the solution conductivity and AC frequency over which positive dielectrophoresis occurs, the apparent conductivity of taxol-stabilized bovine-brain microtubules in PIPES buffer is measured to be 250 mS m(-1). By maximizing dielectrophoretic forces and minimizing electro-osmotic and electrothermal flow, microtubules are assembled into opposed asters. These experiments demonstrate that AC electrokinetics provides a powerful new tool for kinesin-driven transport applications and for investigating the role of microtubule motors in development and maintenance of the mitotic spindle.

  1. Modeling Separate and Combined Atmospheres in BIO-Plex

    NASA Technical Reports Server (NTRS)

    Jones, Harry; Finn, Cory; Kwauk, Xianmin; Blackwell, Charles; Luna, Bernadette (Technical Monitor)

    2000-01-01

    We modeled BIO-Plex designs with separate or combined atmospheres and then simulated controlling the atmosphere composition. The BIO-Plex is the Bioregenerative Planetary Life Support Systems Test Complex, a large regenerative life support test facility under development at NASA Johnson Space Center. Although plants grow better at above-normal carbon dioxide levels, humans can tolerate even higher carbon dioxide levels. Incinerator exhaust has very high levels of carbon dioxide. An elaborate BIO-Plex design would maintain different atmospheres in the crew and plant chambers and isolate the incinerator exhaust in the airlock. This design easily controls the crew and plant carbon dioxide levels but it uses many gas processors, buffers, and controllers. If all the crew's food is grown inside BIO-Plex, all the carbon dioxide required by the plants is supplied by crew respiration and the incineration of plant and food waste. Because the oxygen mass flow must balance in a closed loop, the plants supply all the oxygen required by the crew and the incinerator. Using plants for air revitalization allows using fewer gas processors, buffers, and controllers. In the simplest design, a single combined atmosphere was used for the crew, the plant chamber, and the incinerator. All gas processors, buffers, and controllers were eliminated. The carbon dioxide levels were necessarily similar for the crew and plants. If most of the food is grown, carbon dioxide can be controlled at the desired level by scheduling incineration. An intermediate design uses one atmosphere for the crew and incinerator chambers and a second for the plant chamber. This allows different carbon dioxide levels for the crew and plants. Better control of the atmosphere is obtained by varying the incineration rate. Less gas processing storage and control is needed if more food is grown.

  2. Modeling Separate and Combined Atmospheres in BIO-Plex

    NASA Technical Reports Server (NTRS)

    Jones, Harry; Finn, Cory; Kwauk, Xian-Min; Blackwell, Charles; Luna, Bernadette (Technical Monitor)

    2000-01-01

    We modeled BIO-Plex designs with separate or combined atmospheres and then simulated controlling the atmosphere composition. The BIO-Plex is the Bioregenerative Planetary Life Support Systems Test Complex, a large regenerative life support test facility under development at NASA Johnson Space Center. Although plants grow better at above-normal carbon dioxide levels, humans can tolerate even higher carbon dioxide levels. incinerator exhaust has very high levels of carbon dioxide. An elaborate BIO-Plex design would maintain different atmospheres in the crew and plant chambers and isolate the incinerator exhaust in the airlock. This design easily controls the crew and plant carbon dioxide levels but it uses many gas processors, buffers, and controllers. If all the crew's food is grown inside BIO-Plex, all the carbon dioxide required by the plants is supplied by crew respiration and the incineration of plant and food waste. Because the oxygen mass flow must balance in a closed loop, the plants supply all the oxygen required by the crew and the incinerator. Using plants for air revitalization allows using fewer gas processors, buffers, and controllers. In the simplest design, a single combined atmosphere was used for the crew, the plant chamber, and the incinerator. All gas processors, buffers, and controllers were eliminated. The carbon dioxide levels were necessarily similar for the crew and plants. If most of the food is grown, carbon dioxide can be controlled at the desired level by scheduling incineration. An intermediate design uses one atmosphere for the crew and incinerator chambers and a second for the plant chamber. This allows different carbon dioxide levels for the crew and plants. Better control of the atmosphere is obtained by varying the incineration rate. Less gas processing, storage, and control is needed if more food is grown.

  3. The Development of Models for Carbon Dioxide Reduction Technologies for Spacecraft Air Revitalization

    NASA Technical Reports Server (NTRS)

    Swickrath, Michael J.; Anderson, Molly

    2012-01-01

    Through the respiration process, humans consume oxygen (O2) while producing carbon dioxide (CO2) and water (H2O) as byproducts. For long term space exploration, CO2 concentration in the atmosphere must be managed to prevent hypercapnia. Moreover, CO2 can be used as a source of oxygen through chemical reduction serving to minimize the amount of oxygen required at launch. Reduction can be achieved through a number of techniques. NASA is currently exploring the Sabatier reaction, the Bosch reaction, and co- electrolysis of CO2 and H2O for this process. Proof-of-concept experiments and prototype units for all three processes have proven capable of returning useful commodities for space exploration. All three techniques have demonstrated the capacity to reduce CO2 in the laboratory, yet there is interest in understanding how all three techniques would perform at a system level within a spacecraft. Consequently, there is an impetus to develop predictive models for these processes that can be readily rescaled and integrated into larger system models. Such analysis tools provide the ability to evaluate each technique on a comparable basis with respect to processing rates. This manuscript describes the current models for the carbon dioxide reduction processes under parallel developmental efforts. Comparison to experimental data is provided were available for verification purposes.

  4. Effects of Humidity Swings on Adsorption Columns for Air Revitalization: Modeling and Experiments

    NASA Technical Reports Server (NTRS)

    LeVan, M. Douglas; Finn, John E.

    1997-01-01

    The goal of this research was to develop a dynamic model which can predict the effect of humidity swings on activated carbon adsorption beds used to remove trace contaminants from the atmosphere in spacecraft. Specifically, the model was to be incorporated into a computer simulation to predict contaminant concentrations exiting the bed as a function of time after a humidity swing occurs. Predicted breakthrough curves were to be compared to experimentally measured results. In all respects the research was successful. The two major aspects of this research were the mathematical model and the experiments. Experiments were conducted by Mr. Appel using a fixed-bed apparatus at NASA-Ames Research Center during the summers of 1994 and 1995 and during the first 8 months of 1996. Mr. Appel conducted most of his mathematical modeling work at the University of Virginia. The simulation code was used to predict breakthrough curves using adsorption equilibrium correlations developed previously by M. D. LeVan's research group at the University of Virginia. These predictions were compared with the experimental measurements, and this led to improvements in both the simulation code and the apparatus.

  5. The Development of Models for Carbon Dioxide Reduction Technologies for Spacecraft Air Revitalization

    NASA Technical Reports Server (NTRS)

    Swickrath, Michael J.; Anderson, Molly

    2011-01-01

    Through the respiration process, humans consume oxygen (O2) while producing carbon dioxide (CO2) and water (H2O) as byproducts. For long term space exploration, CO2 concentration in the atmosphere must be managed to prevent hypercapnia. Moreover, CO2 can be used as a source of oxygen through chemical reduction serving to minimize the amount of oxygen required at launch. Reduction can be achieved through a number of techniques. The National Aeronautics and Space Administration (NASA) is currently exploring the Sabatier reaction, the Bosch reaction, and co-electrolysis of CO2 and H2O for this process. Proof-of-concept experiments and prototype units for all three processes have proven capable of returning useful commodities for space exploration. While all three techniques have demonstrated the capacity to reduce CO2 in the laboratory, there is interest in understanding how all three techniques would perform at a system-level within a spacecraft. Consequently, there is an impetus to develop predictive models for these processes that can be readily re-scaled and integrated into larger system models. Such analysis tools provide the ability to evaluate each technique on a comparable basis with respect to processing rates. This manuscript describes the current models for the carbon dioxide reduction processes under parallel developmental e orts. Comparison to experimental data is provided were available for veri cation purposes.

  6. 21 CFR 886.1630 - AC-powered photostimulator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered photostimulator. 886.1630 Section 886...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1630 AC-powered photostimulator. (a) Identification. An AC-powered photostimulator is an AC-powered device intended to provide light stimulus...

  7. 21 CFR 886.1630 - AC-powered photostimulator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false AC-powered photostimulator. 886.1630 Section 886...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1630 AC-powered photostimulator. (a) Identification. An AC-powered photostimulator is an AC-powered device intended to provide light stimulus...

  8. 21 CFR 886.1850 - AC-powered slitlamp biomicroscope.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered slitlamp biomicroscope. 886.1850... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1850 AC-powered slitlamp biomicroscope. (a) Identification. An AC-powered slitlamp biomicroscope is an AC-powered device that is...

  9. 21 CFR 886.1850 - AC-powered slitlamp biomicroscope.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false AC-powered slitlamp biomicroscope. 886.1850... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1850 AC-powered slitlamp biomicroscope. (a) Identification. An AC-powered slitlamp biomicroscope is an AC-powered device that is...

  10. 21 CFR 888.1240 - AC-powered dynamometer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false AC-powered dynamometer. 888.1240 Section 888.1240...) MEDICAL DEVICES ORTHOPEDIC DEVICES Diagnostic Devices § 888.1240 AC-powered dynamometer. (a) Identification. An AC-powered dynamometer is an AC-powered device intended for medical purposes to...

  11. 21 CFR 886.4440 - AC-powered magnet.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered magnet. 886.4440 Section 886.4440 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4440 AC-powered magnet. (a) Identification. An AC-powered magnet is an AC-powered device that generates a magnetic field intended to find and...

  12. 21 CFR 886.4440 - AC-powered magnet.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false AC-powered magnet. 886.4440 Section 886.4440 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4440 AC-powered magnet. (a) Identification. An AC-powered magnet is an AC-powered device that generates a magnetic field intended to find and...

  13. 21 CFR 886.4440 - AC-powered magnet.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false AC-powered magnet. 886.4440 Section 886.4440 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4440 AC-powered magnet. (a) Identification. An AC-powered magnet is an AC-powered device that generates a magnetic field intended to find and...

  14. 21 CFR 886.4440 - AC-powered magnet.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false AC-powered magnet. 886.4440 Section 886.4440 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4440 AC-powered magnet. (a) Identification. An AC-powered magnet is an AC-powered device that generates a magnetic field intended to find and...

  15. 21 CFR 886.4440 - AC-powered magnet.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false AC-powered magnet. 886.4440 Section 886.4440 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4440 AC-powered magnet. (a) Identification. An AC-powered magnet is an AC-powered device that generates a magnetic field intended to find and...

  16. 21 CFR 888.1240 - AC-powered dynamometer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered dynamometer. 888.1240 Section 888.1240...) MEDICAL DEVICES ORTHOPEDIC DEVICES Diagnostic Devices § 888.1240 AC-powered dynamometer. (a) Identification. An AC-powered dynamometer is an AC-powered device intended for medical purposes to...

  17. AC Electrokinetics of Physiological Fluids for Biomedical Applications.

    PubMed

    Lu, Yi; Liu, Tingting; Lamanda, Ariana C; Sin, Mandy L Y; Gau, Vincent; Liao, Joseph C; Wong, Pak Kin

    2015-12-01

    Alternating current (AC) electrokinetics is a collection of processes for manipulating bulk fluid mass and embedded objects with AC electric fields. The ability of AC electrokinetics to implement the major microfluidic operations, such as pumping, mixing, concentration, and separation, makes it possible to develop integrated systems for clinical diagnostics in nontraditional health care settings. The high conductivity of physiological fluids presents new challenges and opportunities for AC electrokinetics-based diagnostic systems. In this review, AC electrokinetic phenomena in conductive physiological fluids are described followed by a review of the basic microfluidic operations and the recent biomedical applications of AC electrokinetics. The future prospects of AC electrokinetics for clinical diagnostics are presented.

  18. AC Electrokinetics of Physiological Fluids for Biomedical Applications

    PubMed Central

    Lu, Yi; Liu, Tingting; Lamanda, Ariana C.; Sin, Mandy L Y; Gau, Vincent; Liao, Joseph C.; Wong, Pak Kin

    2016-01-01

    AC electrokinetics is a collection of processes for manipulating bulk fluid mass and embedded objects with AC electric fields. The ability of AC electrokinetics to implement the major microfluidic operations, such as pumping, mixing, concentration and separation, makes it possible to develop integrated systems for clinical diagnostics in non-traditional healthcare settings. The high conductivity of physiological fluids presents new challenges and opportunities for AC electrokinetics based diagnostic systems. In this review, AC electrokinetic phenomena in conductive physiological fluids are described followed by a review of the basic microfluidic operations and the recent biomedical applications of AC electrokinetics. The future prospects of AC electrokinetics for clinical diagnostics are presented. PMID:25487557

  19. Atmospheric Propagation

    NASA Technical Reports Server (NTRS)

    Embleton, Tony F. W.; Daigle, Gilles A.

    1991-01-01

    Reviewed here is the current state of knowledge with respect to each basic mechanism of sound propagation in the atmosphere and how each mechanism changes the spectral or temporal characteristics of the sound received at a distance from the source. Some of the basic processes affecting sound wave propagation which are present in any situation are discussed. They are geometrical spreading, molecular absorption, and turbulent scattering. In geometrical spreading, sound levels decrease with increasing distance from the source; there is no frequency dependence. In molecular absorption, sound energy is converted into heat as the sound wave propagates through the air; there is a strong dependence on frequency. In turbulent scattering, local variations in wind velocity and temperature induce fluctuations in phase and amplitude of the sound waves as they propagate through an inhomogeneous medium; there is a moderate dependence on frequency.

  20. Atmosphere Analyzer

    NASA Technical Reports Server (NTRS)

    1982-01-01

    California Measurements, Inc.'s model PC-2 Aerosol Particle Analyzer is produced in both airborne and ground-use versions. Originating from NASA technology, it is a quick and accurate method of detecting minute amounts of mass loadings on a quartz crystal -- offers utility as highly sensitive detector of fine particles suspended in air. When combined with suitable air delivery system, it provides immediate information on the size distribution and mass concentrations of aerosols. William Chiang, obtained a NASA license for multiple crystal oscillator technology, and initially developed a particle analyzer for NASA use with Langley Research Center assistance. Later his company produced the modified PC-2 for commercial applications Brunswick Corporation uses the device for atmospheric research and in studies of smoke particles in Fires. PC-2 is used by pharmaceutical and chemical companies in research on inhalation toxicology and environmental health. Also useful in testing various filters for safety masks and nuclear installations.

  1. 78 FR 49318 - Availability of Draft Advisory Circular (AC) 90-106A and AC 20-167A

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-13

    ... Federal Aviation Administration Availability of Draft Advisory Circular (AC) 90-106A and AC 20- 167A...: This notice announces the availability of draft Advisory Circular (AC) 90-106A, Enhanced Flight Vision Systems and draft AC 20- 167A, Airworthiness Approval of Enhanced Vision System, Synthetic Vision...

  2. Rural Area Revitalization Act of 1987; and the Rural Development Reorganization Act of 1987. Hearing on H.R. 1800 and H.R. 2026 before the Subcommittee on Conservation, Credit, and Rural Development of the Committee on Agriculture. House of Representatives, One Hundredth Congress, First Session.

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. House Committee on Agriculture.

    Testimony of H.R. 1800, the Rural Area Revitalization Act, and H.R. 2026, the Rural Development Reorganization Act focuses on the need for federal attention to rural problems other than agriculture. The Rural Area Revitalization Act authorizes expansion of capital available for lending in rural areas, a grant program of $25 million per year for…

  3. Design and synthesis of 225Ac radioimmunopharmaceuticals.

    PubMed

    McDevitt, Michael R; Ma, Dangshe; Simon, Jim; Frank, R Keith; Scheinberg, David A

    2002-12-01

    The alpha-particle-emitting radionuclides 213Bi, 211At, 224Ra are under investigation for the treatment of leukemias, gliomas, and ankylosing spondylitis, respectively. 213Bi and 211At were attached to monoclonal antibodies and used as targeted immunotherapeutic agents while unconjugated 224Ra chloride selectively seeks bone. 225Ac possesses favorable physical properties for radioimmunotherapy (10d half-life and 4 net alpha particles), but has a history of unfavorable radiolabeling chemistry and poor metal-chelate stability. We selected functionalized derivatives of DOTA as the most promising to pursue from out of a group of potential 225Ac chelate compounds. A two-step synthetic process employing either MeO-DOTA-NCS or 2B-DOTA-NCS as the chelating moiety was developed to attach 225Ac to monoclonal antibodies. This method was tested using several different IgG systems. The chelation reaction yield in the first step was 93+/-8% radiochemically pure (n=26). The second step yielded 225Ac-DOTA-IgG constructs that were 95+/-5% radiochemically pure (n=27) and the mean percent immunoreactivity ranged from 25% to 81%, depending on the antibody used. This process has yielded several potential novel targeted 225Ac-labeled immunotherapeutic agents that may now be evaluated in appropriate model systems and ultimately in humans.

  4. From Beamline to Scanner with 225Ac

    NASA Astrophysics Data System (ADS)

    Robertson, Andrew K. H.; Ramogida, Caterina F.; Kunz, Peter; Rodriguez-Rodriguez, Cristina; Schaffer, Paul; Sossi, Vesna

    2016-09-01

    Due to the high linear energy transfer and short range of alpha-radiation, targeted radiation therapy using alpha-emitting pharmaceuticals that successfully target small disease clusters will kill target cells with limited harm to healthy tissue, potentially treating the most aggressive forms of cancer. As the parent of a decay chain with four alpha- and two beta-decays, 225Ac is a promising candidate for such a treatment. However, this requires retention of the entire decay chain at the target site, preventing the creation of freely circulating alpha-emitters that reduce therapeutic effect and increase toxicity to non-target tissues. Two major challenges to 225Ac pharmaceutical development exist: insufficient global supply, and the difficulty of preventing toxicity by retaining the entire decay chain at the target site. While TRIUMF works towards large-scale (C i amounts) production of 225Ac, we already use our Isotope Separation On-Line facility to provide small (< 1 mCi) quantities for in-house chemistry and imaging research that aims to improve and assess 225Ac radiopharmaceutical targeting. This presentation provides an overview of this research program and the journey of 225Ac from the beamline to the scanner. This research is funded by the Natural Sciences and Engineering Research Council of Canada.

  5. Integrated Testing of a Carbon Dioxide Removal Assembly and a Temperature-Swing Adsorption Compressor for Closed-Loop Air Revitalization

    NASA Technical Reports Server (NTRS)

    Knox, J. C.; Mulloth, Lila; Frederick, Kenneth; Affleck, Dave

    2003-01-01

    Accumulation and subsequent compression of carbon dioxide that is removed from space cabin are two important processes involved in a closed-loop air revitalization scheme of the International Space Station (ISS). The carbon dioxide removal assembly (CDRA) of ISS currently operates in an open loop mode without a compressor. This paper describes the integrated test results of a flight-like CDRA and a temperature-swing adsorption compressor (TSAC) for carbon dioxide removal and compression. The paper provides details of the TSAC operation at various CO2 loadings and corresponding performance of CDRA.

  6. Potential Cost Savings for Use of 3D Printing Combined With 3D Imaging and CPLM for Fleet Maintenance and Revitalization

    DTIC Science & Technology

    2013-12-04

    pmlkploba=obmloq=pbofbp= = = Potential Cost Savings for Use of 3D Printing Combined With 3D Imaging and CPLM for Fleet Maintenance and Revitalization...REPORT TYPE 3. DATES COVERED 00-00-2013 to 00-00-2013 4. TITLE AND SUBTITLE Potential Cost Savings for Use of 3D Printing Combined With 3D ...oÉëÉ~êÅÜ=mêçÖê~ã= ëéçåëçêÉÇ=oÉéçêí=pÉêáÉë= Potential Cost Savings for Use of 3D Printing Combined With 3D Imaging and CPLM for Fleet Maintenance and

  7. Atmospheric electricity

    NASA Technical Reports Server (NTRS)

    1987-01-01

    In the last three years the focus was on the information contained in the lightning measurement, which is independent of other meteorological measurements that can be made from space. The characteristics of lightning activity in mesoscale convective systems were quantified. A strong relationship was found between lightning activity and surface rainfall. It is shown that lightning provides a precursor signature for wet microbursts (the strong downdrafts that produce windshears hazardous to aircraft) and that the lightning signature is a direct consequence of storm evolution. The Universities Space Research Association (USRA) collaborated with NASA scientists in the preliminary analysis and scientific justification for the design and deployment of an optical instrument which can detect lightning from geostationary orbit. Science proposals for the NASA mesoscale science program and for the Tethered Satellite System were reviewed. The weather forecasting research and unmanned space vehicles. Software was written to ingest and analyze the lightning ground strike data on the MSFC McIDAS system. The capabilities which were developed have a wide application to a number of problems associated with the operational impacts of electrical discharge within the atmosphere.

  8. Numerical simulation of ac plasma arc thermodynamics

    NASA Astrophysics Data System (ADS)

    Wu, Han-Ming; Carey, G. F.; Oakes, M. E.

    1994-05-01

    A mathematical model and approximate analysis for the energy distribution of an ac plasma arc with a moving boundary is developed. A simplified electrical conductivity function is assumed so that the dynamic behavior of the arc may be determined, independent of the gas type. The model leads to a reduced set of non-linear partial differential equations which governs the quasi-steady ac arc. This system is solved numerically and it is found that convection plays an important role, not only in the temperature distribution, but also in arc disruptions. Moreover, disruptions are found to be influenced by convection only for a limited frequency range. The results of the present studies are applicable to the frequnecy range of 10-10(exp 2) Hz which includes most industry ac arc frequencies.

  9. Numerical Simulation of AC Plasma Arc Thermodynamics

    NASA Astrophysics Data System (ADS)

    Wu, Han-Ming; Carey, G. F.; Oakes, M. E.

    1994-05-01

    A mathematical model and approximate analysis for the energy distribution of an ac plasma arc with a moving boundary is developed. A simplified electrical conductivity function is assumed so that the dynamic behavior of the arc may be determined, independent of the gas type. The model leads to a reduced set of non-linear partial differential equations which governs the quasi-steady ac arc. This system is solved numerically and it is found that convection plays an important role, not only in the temperature distribution, but also in arc disruptions. Moreover, disruptions are found to be influenced by convection only for a limited frequency range. The results of the present studies are applicable to the frequency range of 10-102 Hz which includes most industry ac arc frequencies.

  10. Near-infrared echelle-AOTF spectrometer ACS-NIR for the ExoMars Trace Gas Orbiter

    NASA Astrophysics Data System (ADS)

    Trokhimovskiy, Alexander; Korablev, Oleg; Kalinnikov, Yurii K.; Fedorova, Anna; Stepanov, Alexander V.; Titov, Andrei Y.; Dziuban, Ilia; Patrakeev, Andrei; Montmessin, Franck

    2015-09-01

    The near-Infrared echelle-AOTF spectrometer is one channel of the Atmospheric Chemistry Suite (ACS) package dedicated for the studies of the Martian atmosphere on board ExoMars Trace Gas Orbiter planned for launch in 2016. The near-infrared (NIR) channel of ACS is a versatile spectrometer for the spectral range of 0.7-1.6 μm with a resolving power of <20,000. The NIR channel is intended to measure the atmospheric water vapor, aerosols, airglows, in nadir, in solar occultation, and on the limb. The science goals of NIR are basically the same as for SPICAM IR channel presently in flight on board Mars Express ESA orbiter, but it offers significantly better spectral resolution. The instrument employs the principle of an echelle spectrometer with an acoustooptical tunable filter (AOTF) as a preselector. The same principle was employed in SOIR, operated on Venus Express ESA mission in 2006-2014, and in RUSALKA, operated onboard ISS in 2009-2012. The NIR channel of ACS consists of entry optics, the AOTF, a Littrow echelle spectrometer, and an electrically cooled InGaAs detector array. It is a complete block with power and data interfaces, and the overall mass of 3.2 kg. The protoflight model of NIR is completed, calibrated, integrated within the ACS suite, and is undergoing tests at the spacecraft.

  11. The Jovian Atmospheres

    NASA Technical Reports Server (NTRS)

    Allison, Michael (Editor); Travis, Larry D. (Editor)

    1986-01-01

    A conference on the atmosphere of Jupiter produced papers in the areas of thermal and ortho-para hydrogen structure, clouds and chemistry, atmospheric structure, global dynamics, synoptic features and processes, atmospheric dynamics, and future spaceflight opportunities. A session on the atmospheres of Uranus and Neptune was included, and the atmosphere of Saturn was discussed in several papers.

  12. Analysis of Free Legal Counselling for the Great East Japan Earthquake and the Outlook for the Field of Disaster Recovery and Revitalization Law

    PubMed Central

    OKAMOTO, Tadashi

    2016-01-01

    Of the free legal counselling conducted by lawyers following the Great East Japan Earthquake, the results of analysis of approx. 40,000 cases have been disclosed by the Japan Federation of Bar Associations. These analysis results have been used as evidence serving as the basis for system revision and new legislation following the disaster, and have been of value to public policy, to a certain extent. In order to identify methods for realizing policy targets as know-how for public policy through the integration and analysis of legal needs in disaster areas, in FY2012 and thereafter, lectures on the “Disaster Recovery and Revitalization Law” were initiated by the Graduate School of Public Policy, Chuo University; Keio University Law School; and other institutions. Under the Disaster Recovery and Revitalization Law, new public policy education fusing various fields of government, policy, law, disaster prevention and crisis management, etc. has been implemented. By utilizing the database on free legal counselling, it may be possible to identify legal systems that need to be ironed out or problems related to public policy in preparation for a huge disaster such as an earthquake directly striking the Tokyo metropolitan area or an earthquake in the Nankai Trough. It is thought that intensifying study of relevant fields will result in the proposal of new designs in the fields of disaster prevention and crisis management. PMID:28299243

  13. MO-C-BRB-00: President’s Symposium: Revitalizing Scientific Excellence: Turning Research Into Clinical Reality Through Translational Research

    SciTech Connect

    2015-06-15

    between medical physicists, radiologists, oncologists, industry representatives, and other stakeholders. The mission of QIBA is to improve the accuracy and practicality of quantitative image-based biomarkers by increasing precision across devices, patients, and time, an essential step in incorporating quantitative imaging biomarkers into radiology practice. Validated quantitative imaging biomarkers are necessary to support precision medicine initiatives, multimodality / multiparametric applications in medicine, treatment planning and response assessment, and radiogenomics applications. Current applications in the QIBA portfolio extend to cancer diagnosis and treatment, pulmonary diseases, and neurological disorders. The overall goal of this symposium is to illustrate the bidirectional exchange between medical research and clinical practice. Revitalizing scientific excellence in clinical medical physics challenges practitioners to identify clinical limitations, which then drive research innovation; research funded by the NIH and other agencies develops technological solutions to these limitations, which are translated to the care environment to ultimately improve clinical practice in radiology and radiation oncology.

  14. AC Losses of Prototype HTS Transmission Cables

    SciTech Connect

    Demko, J.A.; Dresner, L.; Hughey, R.L.; Lue, J.W.; Olsen, S.K.; Sinha, U.; Tolbert, J.C.

    1998-09-13

    Since 1995 Southwire Company and Oak Ridge National Laboratory (ORNL) have jointly designed, built, and tested nine, l-m long, high temperature superconducting (HTS) transmission cable prototypes. This paper summarizes the AC loss measurements of five of the cables not reported elsewhere, and compares the losses with each other and with theory developed by Dresner. Losses were measured with both a calorimetric and an electrical technique. Because of the broad resistive transition of the HTS tapes, the cables can be operated stably beyond their critical currents. The AC losses were measured in this region as well as below critical currents. Dresner's theory takes into account the broad resistive transition of the HTS tapes and calculates the AC losses both below and above the critical current. The two sets of AC 10SS data agree with each other and with the theory quite welL In particular, at low currents of incomplete penetration, the loss data agree with the theoretical prediction of hysteresis loss based on only the outer two Iayers carrying the total current.

  15. AC power generation from microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Lobo, Fernanda Leite; Wang, Heming; Forrestal, Casey; Ren, Zhiyong Jason

    2015-11-01

    Microbial fuel cells (MFCs) directly convert biodegradable substrates to electricity and carry good potential for energy-positive wastewater treatment. However, the low and direct current (DC) output from MFC is not usable for general electronics except small sensors, yet commercial DC-AC converters or inverters used in solar systems cannot be directly applied to MFCs. This study presents a new DC-AC converter system for MFCs that can generate alternating voltage in any desired frequency. Results show that AC power can be easily achieved in three different frequencies tested (1, 10, 60 Hz), and no energy storage layer such as capacitors was needed. The DC-AC converter efficiency was higher than 95% when powered by either individual MFCs or simple MFC stacks. Total harmonic distortion (THD) was used to investigate the quality of the energy, and it showed that the energy could be directly usable for linear electronic loads. This study shows that through electrical conversion MFCs can be potentially used in household electronics for decentralized off-grid communities.

  16. Organic magnetoresistance under resonant ac drive

    NASA Astrophysics Data System (ADS)

    Roundy, R. C.; Raikh, M. E.

    2013-09-01

    Motivated by a recent experiment, we develop a theory of organic magnetoresistance (OMAR) in the presence of a resonant ac drive. To this end, we perform a thorough analysis of the dynamics of ac-driven electron-hole polaron pair in magnetic field, which is a sum of external and random hyperfine fields. Resonant ac drive affects the OMAR by modifying the singlet content of the eigenmodes. This, in turn, leads to the change of recombination rate, and ultimately, to the change of the spin-blocking that controls the current. Our analysis demonstrates that, upon increasing the drive amplitude, the blocking eigenmodes of the triplet type acquire a singlet admixture and become unblocking. Most surprisingly, the opposite process goes in parallel: new blocking modes emerge from nonblocking precursors as the drive increases. These emergent blocking modes are similar to subradiant modes in the Dicke effect. A nontrivial evolution of eigenmodes translates into a nontrivial behavior of OMAR with the amplitude of the ac drive: it is initially linear, then passes through a maximum, drops, and finally saturates.

  17. A dry-cooled AC quantum voltmeter

    NASA Astrophysics Data System (ADS)

    Schubert, M.; Starkloff, M.; Peiselt, K.; Anders, S.; Knipper, R.; Lee, J.; Behr, R.; Palafox, L.; Böck, A. C.; Schaidhammer, L.; Fleischmann, P. M.; Meyer, H.-G.

    2016-10-01

    The paper describes a dry-cooled AC quantum voltmeter system operated up to kilohertz frequencies and 7 V rms. A 10 V programmable Josephson voltage standard (PJVS) array was installed on a pulse tube cooler (PTC) driven with a 4 kW air-cooled compressor. The operating margins at 70 GHz frequencies were investigated in detail and found to exceed 1 mA Shapiro step width. A key factor for the successful chip operation was the low on-chip power consumption of 65 mW in total. A thermal interface between PJVS chip and PTC cold stage was used to avoid a significant chip overheating. By installing the cryocooled PJVS array into an AC quantum voltmeter setup, several calibration measurements of dc standards and calibrator ac voltages up to 2 kHz frequencies were carried out to demonstrate the full functionality. The results are discussed and compared to systems with standard liquid helium cooling. For dc voltages, a direct comparison measurement between the dry-cooled AC quantum voltmeter and a liquid-helium based 10 V PJVS shows an agreement better than 1 part in 1010.

  18. 48 CFR Appendixes A-C to Chapter 7 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false A Appendixes A-C to Chapter 7 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT Appendixes A-C to Chapter 7...

  19. 48 CFR Appendixes A-C to Chapter 7 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false A Appendixes A-C to Chapter 7 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT Appendixes A-C to Chapter 7...

  20. AC losses in a HTS coil carrying DC current in AC external magnetic field

    NASA Astrophysics Data System (ADS)

    Ogawa, J.; Zushi, Y.; Fukushima, M.; Tsukamoto, O.; Suzuki, E.; Hirakawa, M.; Kikukawa, K.

    2003-10-01

    We electrically measured AC losses in a Bi2223/Ag-sheathed pancake coil excited by a DC current in AC external magnetic field. Losses in the coil contain two kinds of loss components that are the magnetization losses and dynamic resistance losses. In the measurement, current leads to supply a current to the coil were specially arranged to suppress electromagnetic coupling between the coil current and the AC external magnetic field. A double pick-up coils method was used to suppress a large inductive voltage component contained in voltage signal for measuring the magnetization losses. It was observed that the magnetization losses were dependent on the coil current and that a peak of a curve of the loss factor vs. amplitude of the AC external magnetic field shifted to lower amplitude of the AC magnetic field as the coil current increased. This result suggests the full penetration magnetic field of the coil tape decreases as the coil current increases. The dynamic resistance losses were measured by measuring a DC voltage appearing between the coil terminals. It was observed that the DC voltage appearing in the coil subject to the AC external magnetic field was much larger than that in the coil subject to DC magnetic field.

  1. Evaluation of modern IGBT-modules for hard-switched AC/DC/AC converters

    SciTech Connect

    Blaabjerg, F.; Pedersen, J.K.; Jaeger, U.

    1995-12-31

    The development of IGBT devices is still producing faster devices with lower losses. The applications become more advanced like a complete hard-switched AC/DC/AC converter with almost clean input current and regenerating capabilities. This paper will first focus on a detailed characterization and comparison of eight different IGBT-modules representing state-of-the-art for both PT and NPT technologies. The voltage level of the devices is 1,200V and 1,600V/1,700V. The characterization is done on an advanced measurement system which is briefly described. The characterization is based on static and dynamic tests for both IGBT and the diodes in the IGBT-modules at a junction temperature at 125 C. The comparison is first done directly based on conduction losses and switching losses, and later the measurements are used in a loss model for a complete AC/DC/AC converter application. In the AC/DC/AC converter the power losses are modelled, and different operating conditions are compared like different voltage levels in the DC-link. It is concluded dependent on operation conditions different devices will be preferable, but the high voltage devices have the highest losses even at a high operating voltage.

  2. 7 CFR 1737.31 - Area Coverage Survey (ACS).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false Area Coverage Survey (ACS). 1737.31 Section 1737.31... Studies-Area Coverage Survey and Loan Design § 1737.31 Area Coverage Survey (ACS). (a) The Area Coverage Survey (ACS) is a market forecast of service requirements of subscribers in a proposed service area....

  3. 7 CFR 1737.31 - Area Coverage Survey (ACS).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Area Coverage Survey (ACS). 1737.31 Section 1737.31... Studies-Area Coverage Survey and Loan Design § 1737.31 Area Coverage Survey (ACS). (a) The Area Coverage Survey (ACS) is a market forecast of service requirements of subscribers in a proposed service area....

  4. 7 CFR 1737.31 - Area Coverage Survey (ACS).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false Area Coverage Survey (ACS). 1737.31 Section 1737.31... Studies-Area Coverage Survey and Loan Design § 1737.31 Area Coverage Survey (ACS). (a) The Area Coverage Survey (ACS) is a market forecast of service requirements of subscribers in a proposed service area....

  5. 7 CFR 1737.31 - Area Coverage Survey (ACS).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 11 2011-01-01 2011-01-01 false Area Coverage Survey (ACS). 1737.31 Section 1737.31... Studies-Area Coverage Survey and Loan Design § 1737.31 Area Coverage Survey (ACS). (a) The Area Coverage Survey (ACS) is a market forecast of service requirements of subscribers in a proposed service area....

  6. 21 CFR 880.5500 - AC-powered patient lift.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false AC-powered patient lift. 880.5500 Section 880.5500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Devices § 880.5500 AC-powered patient lift. (a) Identification. An AC-powered lift is an...

  7. Methods for Addressing Missing Data with Applications from ACS Exams

    ERIC Educational Resources Information Center

    Brandriet, Alexandra; Holme, Thomas

    2015-01-01

    As part of the ACS Examinations Institute (ACS-EI) national norming process, student performance data sets are collected from professors at colleges and universities from around the United States. Because the data sets are collected on a volunteer basis, the ACS-EI often receives data sets with only students' total scores and without the students'…

  8. Oklahoma City Revitalization

    EPA Pesticide Factsheets

    Since the beginning of their Brownfields Program in 2003, Oklahoma City has been the recipient of nine EPA Brownfields Grants, creating a new city from the inside out. So far, 45 properties have been assessed and/or remediated.

  9. Revitalizing Nuclear Safety Research.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC.

    This report covers the general issues involved in nuclear safety research and points out the areas needing detailed consideration. Topics included are: (1) "Principles of Nuclear Safety Research" (examining who should fund, who should conduct, and who should set the agenda for nuclear safety research); (2) "Elements of a Future…

  10. Faculty Retirement Transitions Revitalized

    ERIC Educational Resources Information Center

    Van Ummersen, Claire; Duranleau, Lauren; McLaughlin, Jean

    2013-01-01

    It has been almost ten years since the American Council on Education (ACE) began to raise awareness of the importance of workplace flexibility in faculty careers and to encourage colleges and universities to support faculty in better integrating their professional and personal lives. With the generous support of the Alfred P. Sloan Foundation, ACE…

  11. Peer Review Undergoing Revitalization

    ERIC Educational Resources Information Center

    Sawchuk, Stephen

    2009-01-01

    Established in the 142,000-student Montgomery County, Maryland, district in 1999, peer assistance and review (PAR)--or "peer review," as it is occasionally called--is actually an old idea. In 1981, the then-president of the Toledo Federation of Teachers, Dal Lawrence, helped create the first PAR program. Almost 30 years later, only a…

  12. Revitalizing HEC at NASA

    NASA Technical Reports Server (NTRS)

    Brooks, Walt

    2005-01-01

    This talk will review the focus on NASA advances in SSI supercomputing technology over the last 4 years, the development of the worlds largest Origins. the development of the cooperative program that developed the CRAY and SGI system in FY03 and the efforts that led to the formulation and approval of the NAS program and Columbia Project. Finally a projection of the RBD and operations focus in HEC for the next 3-5 years will be described. (use NAS url)

  13. Community Parks Revitalization Act

    THOMAS, 112th Congress

    Sen. Hagan, Kay R. [D-NC

    2012-09-20

    09/20/2012 Read twice and referred to the Committee on Banking, Housing, and Urban Affairs. (text of measure as introduced: CR S6549-6552) (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  14. Large aperture ac interferometer for optical testing.

    PubMed

    Moore, D T; Murray, R; Neves, F B

    1978-12-15

    A 20-cm clear aperture modified Twyman-Green interferometer is described. The system measures phase with an AC technique called phase-lock interferometry while scanning the aperture with a dual galvanometer scanning system. Position information and phase are stored in a minicomputer with disk storage. This information is manipulated with associated software, and the wavefront deformation due to a test component is graphically displayed in perspective and contour on a CRT terminal.

  15. YBCO Coated Conductors with Reduced AC Losses

    DTIC Science & Technology

    2008-01-30

    application such as turbo- generators and gyrotron magnets . The major reason is the enhanced in-field performance at 50-65 K and the proven...transformers, current limiters and the stators of rotating equipment. Low AC-loss in 2G HTS requires wire components with low magnetism , and an YBCO...layer with low transport and low hysteretic losses in an alternating magnetic field. The latter loss type requires a suitable filamentization technique

  16. AC plasma anemometer—characteristics and design

    NASA Astrophysics Data System (ADS)

    Marshall, Curtis; Matlis, Eric; Corke, Thomas; Gogineni, Sivaram

    2015-08-01

    The characteristics and design of a high-bandwidth flow sensor that uses an AC glow discharge (plasma) as the sensing element is presented. The plasma forms in the air gap between two protruding low profile electrodes attached to a probe body. The output from the anemometer is an amplitude modulated version of the AC voltage input that contains information about the mean and fluctuating velocity components. The anemometer circuitry includes resistance and capacitance elements that simulate a dielectric-barrier to maintain a diffuse plasma, and a constant-current feedback control that maintains operation within the desired glow discharge regime over an extended range of air velocities. Mean velocity calibrations are demonstrated over a range from 0 to 140 m s-1. Over this velocity range, the mean output voltage varied linearly with air velocity, providing a constant static sensitivity. The effect of the electrode gap and input AC carrier frequency on the anemometer static sensitivity and dynamic response are investigated. Experiments are performed to compare measurements obtained with a plasma sensor operating at two AC carrier frequencies against that of a constant-temperature hot-wire. All three sensors were calibrated against the same known velocity reference. An uncertainty based on the standard deviation of the velocity calibration fit was applied to the mean and fluctuating velocity measurements of the three sensors. The motivation is not to replace hot-wires as a general measurement tool, but rather as an alternative to hot-wires in harsh environments or at high Mach numbers where they either have difficulty in surviving or lack the necessary frequency response.

  17. THE ACS NEARBY GALAXY SURVEY TREASURY

    SciTech Connect

    Dalcanton, Julianne J.; Williams, Benjamin F.; Rosema, Keith; Gogarten, Stephanie M.; Christensen, Charlotte; Gilbert, Karoline; Hodge, Paul; Seth, Anil C.; Dolphin, Andrew; Holtzman, Jon; Skillman, Evan D.; Weisz, Daniel; Cole, Andrew; Girardi, Leo; Karachentsev, Igor D.; Olsen, Knut; Freeman, Ken; Gallart, Carme; De Jong, Roelof S. E-mail: ben@astro.washington.edu E-mail: stephanie@astro.washington.edu E-mail: fabio@astro.washington.edu E-mail: aseth@cfa.harvard.edu

    2009-07-15

    The ACS Nearby Galaxy Survey Treasury (ANGST) is a systematic survey to establish a legacy of uniform multi-color photometry of resolved stars for a volume-limited sample of nearby galaxies (D < 4 Mpc). The survey volume encompasses 69 galaxies in diverse environments, including close pairs, small and large groups, filaments, and truly isolated regions. The galaxies include a nearly complete range of morphological types spanning a factor of {approx}10{sup 4} in luminosity and star formation rate. The survey data consist of images taken with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope (HST), supplemented with archival data and new Wide Field Planetary Camera 2 (WFPC2) imaging taken after the failure of ACS. Survey images include wide field tilings covering the full radial extent of each galaxy, and single deep pointings in uncrowded regions of the most massive galaxies in the volume. The new wide field imaging in ANGST reaches median 50% completenesses of m {sub F475W} = 28.0 mag, m {sub F606W} = 27.3 mag, and m {sub F814W} = 27.3 mag, several magnitudes below the tip of the red giant branch (TRGB). The deep fields reach magnitudes sufficient to fully resolve the structure in the red clump. The resulting photometric catalogs are publicly accessible and contain over 34 million photometric measurements of >14 million stars. In this paper we present the details of the sample selection, imaging, data reduction, and the resulting photometric catalogs, along with an analysis of the photometric uncertainties (systematic and random), for both ACS and WFPC2 imaging. We also present uniformly derived relative distances measured from the apparent magnitude of the TRGB.

  18. Graphs for Isotopes of 89-Ac (Actinium)

    NASA Astrophysics Data System (ADS)

    Sukhoruchkin, S. I.; Soroko, Z. N.

    This document is part of the Supplement containing the complete sets of data of Subvolume B `Nuclei with Z = 55 - 100' of Volume 22 `Nuclear Binding Energies and Atomic Masses' of Landolt-Börnstein - Group I `Elementary Particles, Nuclei and Atoms', and additionally including data for nuclei with Z = 101 - 130. It provides a graphic representation of nucleon separation energies and residual interaction parameters for isotopes of the chemical element 89-Ac (Actinium, atomic number Z = 89).

  19. The ACS Nearby Galaxy Survey Treasury

    NASA Astrophysics Data System (ADS)

    Dalcanton, Julianne J.; Williams, Benjamin F.; Seth, Anil C.; Dolphin, Andrew; Holtzman, Jon; Rosema, Keith; Skillman, Evan D.; Cole, Andrew; Girardi, Léo; Gogarten, Stephanie M.; Karachentsev, Igor D.; Olsen, Knut; Weisz, Daniel; Christensen, Charlotte; Freeman, Ken; Gilbert, Karoline; Gallart, Carme; Harris, Jason; Hodge, Paul; de Jong, Roelof S.; Karachentseva, Valentina; Mateo, Mario; Stetson, Peter B.; Tavarez, Maritza; Zaritsky, Dennis; Governato, Fabio; Quinn, Thomas

    2009-07-01

    The ACS Nearby Galaxy Survey Treasury (ANGST) is a systematic survey to establish a legacy of uniform multi-color photometry of resolved stars for a volume-limited sample of nearby galaxies (D < 4 Mpc). The survey volume encompasses 69 galaxies in diverse environments, including close pairs, small and large groups, filaments, and truly isolated regions. The galaxies include a nearly complete range of morphological types spanning a factor of ~104 in luminosity and star formation rate. The survey data consist of images taken with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope (HST), supplemented with archival data and new Wide Field Planetary Camera 2 (WFPC2) imaging taken after the failure of ACS. Survey images include wide field tilings covering the full radial extent of each galaxy, and single deep pointings in uncrowded regions of the most massive galaxies in the volume. The new wide field imaging in ANGST reaches median 50% completenesses of m F475W = 28.0 mag, m F606W = 27.3 mag, and m F814W = 27.3 mag, several magnitudes below the tip of the red giant branch (TRGB). The deep fields reach magnitudes sufficient to fully resolve the structure in the red clump. The resulting photometric catalogs are publicly accessible and contain over 34 million photometric measurements of >14 million stars. In this paper we present the details of the sample selection, imaging, data reduction, and the resulting photometric catalogs, along with an analysis of the photometric uncertainties (systematic and random), for both ACS and WFPC2 imaging. We also present uniformly derived relative distances measured from the apparent magnitude of the TRGB.

  20. Atmospheric and Space Sciences: Neutral Atmospheres

    NASA Astrophysics Data System (ADS)

    Yiǧit, Erdal

    2015-09-01

    The SpringerBriefs on Atmospheric and Space Sciences in two volumes presents a concise and interdisciplinary introduction to the basic theory, observation & modeling of atmospheric and ionospheric coupling processes on Earth. The goal is to contribute toward bridging the gap between meteorology, aeronomy, and planetary science. In addition recent progress in several related research topics, such atmospheric wave coupling and variability, is discussed. Volume 1 will focus on the atmosphere, while Volume 2 will present the ionosphere— the plasma environment. Volume 1 is aimed primarily at (research) students and researchers that would like to gain quick insight in atmospheric sciences and current research. It also is a useful tool for professors who would like to develop a course in atmospheric physics.

  1. Level structure and reflection asymmetric shape in sup 223 Ac

    SciTech Connect

    Sheline, R.K.; Liang, C.F.; Paris, P. )

    1990-07-20

    Mass separated sources of {sup 227}Pa (separated as PaF{sub 4}{sup +} ions) were used to study the level structure of {sup 223}Ac following alpha decay. The levels in {sup 223}Ac are interpreted as K = 5/2{sup {plus minus}} parity doublet bands which occur naturally in reflection asymmetric models and the multiphonon octupole model. The anomalous structure of the K = 3/2{sup {minus}} band is explained in terms of Coriolis coupling. The low lying parity doublet bands in {sup 223}Ac, {sup 225}Ac, and {sup 227}Ac are compared and contrasted.

  2. Channel model for AC electric arc

    NASA Astrophysics Data System (ADS)

    Larsen, H. L.

    1993-06-01

    This report contains the results from calculations of free-burning AC electric arcs in argon. In order to calculate the arc current and arc voltage, the external electric circuit must be taken into consideration. The external circuit is modeled by an equivalent circuit consisting of an ideal AC voltage source, a loss resistance, and an inductance. The qualitative behavior of the current-voltage characteristic is in agreement with observed characteristics, but experimental data are necessary in order to check whether the calculated power loss is reasonable. Non-symmetry was modeled by introducing different anode and cathode falls in the two half periods. An attempt at taking into account different cathode current densities in the two half periods, depending on whether the electrode or silicon melt is cathode, did not give satisfactory results. Thermionic emission was assumed in both half periods, but this may not be the right mechanism when the silicon melt is cathode. The time delay of the AC arc compared to the DC case is modeled by a time constant. It was shown that this preset time constant must be in agreement with the mean 'mechanical' relaxation time in the arc in order to fulfill the energy balance. By updating the time constant until this is achieved, the time constant is eliminated as a parameter that must be chosen a priori.

  3. The ACS Nearby Galaxy Survey Treasury

    NASA Astrophysics Data System (ADS)

    Weisz, Daniel R.

    2010-01-01

    The ACS Nearby Galaxy Survey Treasury (ANGST) is a systematic survey to establish a legacy of uniform multi-color photometry of resolved stars for a volume-limited sample of nearby galaxies (D<4Mpc). The survey volume encompasses 69 galaxies in diverse environments, including close pairs, small & large groups, filaments, and truly isolated regions. The galaxies include a nearly complete range of morphological types spanning a factor of 104 in luminosity and star formation rate. The survey data consists of images taken with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope, supplemented with archival data and new Wide Field Planetary Camera (WFPC2) imaging taken after the failure of ACS. Survey images include wide field tilings covering the full radial extent of each galaxy, and single deep pointings in uncrowded regions of the most massive galaxies in the volume. We will discuss the many ways in which this data set is being used to reconstruct the star formation history of galaxies within the local volume.

  4. Total AC losses in twisted and untwisted multifilamentary Bi-2223 superconducting tapes carrying AC transport current in AC longitudinal magnetic field

    NASA Astrophysics Data System (ADS)

    Amemiya, Naoyuki; Jin, Feng; Jiang, Zhenan; Shirai, Shunsuke; ten Haken, Bennie; Rabbers, Jan-Jaap; Ayai, Naoki; Hayashi, Kazuhiko

    2003-03-01

    In some electrical apparatuses, superconducting tapes are exposed to the longitudinal magnetic field. In this work, AC losses were measured in twisted and untwisted Bi-2223 tapes carrying AC transport current in the AC longitudinal magnetic field. In twisted tapes, the transport, magnetization and total losses depend on the relative direction of the longitudinal magnetic field to the direction of the transport current, while the field direction does not influence the AC loss characteristics in untwisted tapes. In the Z-twisted tapes, the total AC loss is larger in the longitudinal magnetic field that is anti-parallel to the transport current than in the longitudinal magnetic field of another direction. Numerical analysis shows that this field direction dependence of the total AC loss results from the change in the current distribution. In the longitudinal magnetic field that is anti-parallel to the transport current, the total AC loss in the Z-twisted tape is more than that in the untwisted tape. This dependence on the field direction is reversed in S-twisted tapes. It is to be noted that the twist increases the total AC loss in a longitudinal magnetic field of a certain direction, while it reduces the AC loss in the transverse magnetic field.

  5. AC loss measurements of twisted and untwisted BSCCO multifilamentary tapes

    NASA Astrophysics Data System (ADS)

    Jiang, Zhenan; Amemiya, Naoyuki; Nishioka, Takamasa; Oh, Sang-Soo

    2005-01-01

    AC losses in twisted and untwisted BSCCO multifilamentary superconducting tapes with Ag matrix developed in DAPAS program were measured by an electrical method. Magnetization and transport losses were measured by a pick-up coil and by a voltage taps. Total AC loss during simultaneous application of AC transport current and an AC transverse magnetic field was given by the sum of the magnetization and transport losses measured during this simultaneous application. The magnetization loss without transport current of untwisted and twisted tapes was measured first to evaluate the effect of twisting to decouple filaments. Then, the total AC loss of the twisted tape was measured in transverse magnetic fields with various amplitudes and orientations, while the amplitude of the transport current was fixed. The measured total AC loss in a parallel transverse magnetic field was compared with some theoretical models to study the detailed characteristics of the measured total AC loss of the sample.

  6. Development of a hardware-based AC microgrid for AC stability assessment

    NASA Astrophysics Data System (ADS)

    Swanson, Robert R.

    As more power electronic-based devices enable the development of high-bandwidth AC microgrids, the topic of microgrid power distribution stability has become of increased interest. Recently, researchers have proposed a relatively straightforward method to assess the stability of AC systems based upon the time-constants of sources, the net bus capacitance, and the rate limits of sources. In this research, a focus has been to develop a hardware test system to evaluate AC system stability. As a first step, a time domain model of a two converter microgrid was established in which a three phase inverter acts as a power source and an active rectifier serves as an adjustable constant power AC load. The constant power load can be utilized to create rapid power flow transients to the generating system. As a second step, the inverter and active rectifier were designed using a Smart Power Module IGBT for switching and an embedded microcontroller as a processor for algorithm implementation. The inverter and active rectifier were designed to operate simultaneously using a synchronization signal to ensure each respective local controller operates in a common reference frame. Finally, the physical system was created and initial testing performed to validate the hardware functionality as a variable amplitude and variable frequency AC system.

  7. The Hubble Legacy Archive ACS grism data

    NASA Astrophysics Data System (ADS)

    Kümmel, M.; Rosati, P.; Fosbury, R.; Haase, J.; Hook, R. N.; Kuntschner, H.; Lombardi, M.; Micol, A.; Nilsson, K. K.; Stoehr, F.; Walsh, J. R.

    2011-06-01

    A public release of slitless spectra, obtained with ACS/WFC and the G800L grism, is presented. Spectra were automatically extracted in a uniform way from 153 archival fields (or "associations") distributed across the two Galactic caps, covering all observations to 2008. The ACS G800L grism provides a wavelength range of 0.55-1.00 μm, with a dispersion of 40 Å/pixel and a resolution of ~80 Å for point-like sources. The ACS G800L images and matched direct images were reduced with an automatic pipeline that handles all steps from archive retrieval, alignment and astrometric calibration, direct image combination, catalogue generation, spectral extraction and collection of metadata. The large number of extracted spectra (73,581) demanded automatic methods for quality control and an automated classification algorithm was trained on the visual inspection of several thousand spectra. The final sample of quality controlled spectra includes 47 919 datasets (65% of the total number of extracted spectra) for 32 149 unique objects, with a median iAB-band magnitude of 23.7, reaching 26.5 AB for the faintest objects. Each released dataset contains science-ready 1D and 2D spectra, as well as multi-band image cutouts of corresponding sources and a useful preview page summarising the direct and slitless data, astrometric and photometric parameters. This release is part of the continuing effort to enhance the content of the Hubble Legacy Archive (HLA) with highly processed data products which significantly facilitate the scientific exploitation of the Hubble data. In order to characterize the slitless spectra, emission-line flux and equivalent width sensitivity of the ACS data were compared with public ground-based spectra in the GOODS-South field. An example list of emission line galaxies with two or more identified lines is also included, covering the redshift range 0.2 - 4.6. Almost all redshift determinations outside of the GOODS fields are new. The scope of science projects

  8. Development of a Next-Generation Membrane-Integrated Adsorption Processor for CO2 Removal and Compression for Closed-Loop Air Revitalization Systems

    NASA Technical Reports Server (NTRS)

    Mulloth, Lila; LeVan, Douglas

    2002-01-01

    The current CO2 removal technology of NASA is very energy intensive and contains many non-optimized subsystems. This paper discusses the concept of a next-generation, membrane integrated, adsorption processor for CO2 removal nd compression in closed-loop air revitalization systems. This processor will use many times less power than NASA's current CO2 removal technology and will be capable of maintaining a lower CO2 concentration in the cabin than that can be achieved by the existing CO2 removal systems. The compact, consolidated, configuration of gas dryer, CO2 separator, and CO2 compressor will allow continuous recycling of humid air in the cabin and supply of compressed CO2 to the reduction unit for oxygen recovery. The device has potential application to the International Space Station and future, long duration, transit, and planetary missions.

  9. The West End Revitalization Association (WERA)'s right to basic amenities movement: voice and language of ownership and management of public health solutions in Mebane, North Carolina.

    PubMed

    Wilson, Omega R; Bumpass, Natasha G; Wilson, Omari M; Snipes, Marilyn H

    2008-01-01

    The West End Revitalization Association (WERA) cultivated strategies for assessing environmental hazards, managing stakeholder participation, and implementing corrective actions in three low-income African American communities in Mebane, North Carolina. The community voices evolved into language to drive WERA's "Right to Basic Amenities Movement" as a way to address health, legal, and quality-of-life disparities. The sustainability of this movement depends on communicating a solutions process with funding equity. Disparities are a way of life for impacted residents: dusty dead-end streets, contaminated drinking water, failed backyard septic tanks, and putrid odors. WERA organized on "common knowledge" for effective use of public health statutes and Title VI of the Civil Rights Act of 1964. WERA's board, staff, and volunteers exercised their voices in the language of government, public health, university research, and legal agencies. WERA's best practices and lessons learned may influence public policy in comparable communities in North Carolina and throughout the nation.

  10. Integrated Testing of a 4-Bed Molecular Sieve and a Temperature-Swing Adsorption Compressor for Closed-Loop Air Revitalization

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Mulloth, Lila M.; Affleck, David L.

    2004-01-01

    Accumulation and subsequent compression of carbon dioxide that is removed from space cabin are two important processes involved in a closed-loop air revitalization scheme of the International Space Station (ISS). The 4-Bed Molecular Sieve (4BMS) of ISS currently operates in an open loop mode without a compressor. This paper reports the integrated 4BMS and liquid-cooled TSAC testing conducted during the period of March 3 to April 18, 2003. The TSAC prototype was developed at NASA Ames Research Center (ARC). The 4BMS was modified to a functionally flight-like condition at NASA Marshall Space Flight Center (MSFC). Testing was conducted at MSFC. The paper provides details of the TSAC operation at various CO2 loadings and corresponding performance of CDRA.

  11. Atmosphere behavior in gas-closed mouse-algal systems: An experimental and modelling study

    NASA Astrophysics Data System (ADS)

    Averner, Maurice M.; Moore, Berrien; Bartholomew, Irene; Wharton, Robert

    Concepts of biologically-based regenerative life support systems anticipate the use of photosynthetic organisms for air revitalization. However, mismatches in the rates of production and uptake of oxygen or carbon dioxide between the crew and the plants will lead to an accumulation or depletion of these gases beyond tolerable limits. One method for correcting these atmospheric changes is to use physicochemical devices. This would conflict with the constraint of minimal size and weight imposed upon the successful development of a competitive bioregenerative system. An alternate control strategy is based upon reducing the gas exchange mismatch by manipulation of those environmental parameters known to affect plant or algae gas exchange ratios. We have initiated a research program using a dual approach of mathematical modelling and laboratory experimentation aimed at examining the gas exchange characteristics of artificial animal/plant systems closed to the ambient atmosphere. Our goal is to develop control techniques and management strategies for maintaining the atmospheric levels of carbon dioxide and oxygen at physiological levels. A mathematical model simulating the atmospheric behavior in these systems has been developed and an experimental gas-closed system has been constructed. These will be described and preliminary results will be presented.

  12. The application of homemade Neosinocalamus affinis AC in electrokinetic removal technology on heavy metal removal from the MSWI fly ash

    PubMed Central

    Liu, Kexiang; Huang, Tao; Huang, Xiao; Yu, Lin; Muhammad, Faheem; Jiao, Binquan; Li, Dongwei

    2016-01-01

    This present paper was focused on the manufacture of activated carbon (AC) and its application in the electrokinetic remediation (EKR) technology on removal of the heavy metals (HMs) from the municipal solid waste incineration fly ash. AC was produced from Neosinocalamus affinis (NF) by chemical activation with H3PO4 in N2 atmosphere, the effects of activation temperatures, soaking time and impregnation ratios on the adsorption capacity of AC on HMs were examined through equilibrium adsorption experiments. The AC produced under the condition of 450 °C of activation temperature, 10 h of soaking time and 1.5 of impregnation ration was applied in the EKR experiment. The addition of AC in the S3-region of the electrolyzer could effectively improve the removal efficiencies of HMs. The technical parameters of voltage gradient, processing time and proportion were further optimized in the coupled experiments, the maximum removal of Cu, Zn, Cd, and Pb was 84.93%, 69.61%, 79.57%, and 78.55% respectively obtained under the optimal operating conditions of 2 V/cm of voltage gradient, 8 d of processing time and 20% of proportion. PMID:28000710

  13. The application of homemade Neosinocalamus affinis AC in electrokinetic removal technology on heavy metal removal from the MSWI fly ash

    NASA Astrophysics Data System (ADS)

    Liu, Kexiang; Huang, Tao; Huang, Xiao; Yu, Lin; Muhammad, Faheem; Jiao, Binquan; Li, Dongwei

    2016-12-01

    This present paper was focused on the manufacture of activated carbon (AC) and its application in the electrokinetic remediation (EKR) technology on removal of the heavy metals (HMs) from the municipal solid waste incineration fly ash. AC was produced from Neosinocalamus affinis (NF) by chemical activation with H3PO4 in N2 atmosphere, the effects of activation temperatures, soaking time and impregnation ratios on the adsorption capacity of AC on HMs were examined through equilibrium adsorption experiments. The AC produced under the condition of 450 °C of activation temperature, 10 h of soaking time and 1.5 of impregnation ration was applied in the EKR experiment. The addition of AC in the S3-region of the electrolyzer could effectively improve the removal efficiencies of HMs. The technical parameters of voltage gradient, processing time and proportion were further optimized in the coupled experiments, the maximum removal of Cu, Zn, Cd, and Pb was 84.93%, 69.61%, 79.57%, and 78.55% respectively obtained under the optimal operating conditions of 2 V/cm of voltage gradient, 8 d of processing time and 20% of proportion.

  14. Deletion of the AcMNPV core gene ac109 results in budded virions that are non-infectious

    SciTech Connect

    Fang Minggang; Nie, Yingchao; Theilmann, David A.

    2009-06-20

    Autographa californica multiple nucleopolyhedrovirus (AcMNPV) ac109 is a core gene and its function in the virus life cycle is unknown. To determine its role in the baculovirus life cycle, we used the AcMNPV bacmid system to generate an ac109 deletion virus (vAc{sup 109KO}). Fluorescence and light microscopy showed that transfection of vAc{sup 109KO} results in a single-cell infection phenotype. Viral DNA replication is unaffected and the development of occlusion bodies in vAc{sup 109KO}-transfected cells evidenced progression to the very late phases of viral infection. Western blot and confocal immunofluorescence analysis showed that AC109 is expressed in the cytoplasm and nucleus throughout infection. In addition, AC109 is a structural protein as it was detected in both budded virus (BV) and occlusion derived virus in both the envelope and nucleocapsid fractions. Titration assays by qPCR and TCID{sub 50} showed that vAc{sup 109KO} produced BV but the virions are non-infectious. The vAc{sup 109KO} BV were indistinguishable from the BV of repaired and wild type control viruses as determined by negative staining and electron microscopy.

  15. The ACS Nearby Galaxy Survey Treasury

    NASA Astrophysics Data System (ADS)

    Dalcanton, Julianne; Williams, B.; Gogarten, S.; Weisz, D.; Skillman, E.; Seth, A.; ANGST Team

    2007-12-01

    The ACS Nearby Galaxy Survey Treasury program (ANGST) is a program to measure photometry for millions of stars in a volume limited sample of 70 nearby galaxies. With this data set, we are deriving spatially resolved star formation histories for both dwarfs and spirals in the local volume. I will highlight initial results from the survey, including ancient star formation histories for massive spirals, halos around dwarf galaxies, spatially-resolved star formation histories in dwarfs and spirals, and the detection of variable stars. I will also discuss the ANGST involved with switching to WFPC2. This program is funded by NASA grant HST GO-10915, administered by STScI.

  16. Nonlinear studies of AC electrokinetic micropumps

    NASA Astrophysics Data System (ADS)

    Bruus, Henrik; Olesen, Laurits H.; Ajdari, Armand

    2006-03-01

    Recent experiments have demonstrated that AC electrokinetic micropumps permit integrable, local, and fast pumping (velocities ˜ mm/s) with low driving voltage of a few volts only. However, they also displayed many quantitative and qualitative discrepancies with existing theories. We therefore extend the latter theories to account for three experimentally relevant effects: (i) vertical confinement of the pumping channel, (ii) Faradaic currents from electrochemical reactions at the electrodes, and (iii) nonlinear surface capacitance of the Debye layer. We report here that these effects indeed affect the pump performance in a way that we can rationalize by physical arguments.

  17. Inverse ac Josephson effect at terahertz frequencies

    NASA Astrophysics Data System (ADS)

    Danchi, W. C.; Golightly, W. J.; Sutton, E. C.

    1989-04-01

    Using the Werthamer (1966) theory of superconducting tunnel junctions, it is shown that zero-crossing ac Josephson steps can occur at frequencies much higher than those expected previously, as long as the voltage waveform is nearly sinusoidal. Limits on the amount of permitted rounding of the Riedel (1964) peak were derived from analytical calculations, and numerical frequency-domain and time-domain computations for realistic junctions were carried out, yielding support for these limits. It is shown that previous arguments that zero-crossing steps could never be observed above the value of half the gap voltage are incorrect, due to the neglect of the Riedel peak.

  18. Stellar atmospheric structural patterns

    NASA Technical Reports Server (NTRS)

    Thomas, R. N.

    1983-01-01

    The thermodynamics of stellar atmospheres is discussed. Particular attention is given to the relation between theoretical modeling and empirical evidence. The characteristics of distinctive atmospheric regions and their radical structures are discussed.

  19. Earth's changeable atmosphere

    NASA Astrophysics Data System (ADS)

    2016-06-01

    Billions of years ago, high atmospheric greenhouse gas concentrations were vital to life's tenuous foothold on Earth. Despite new constraints, the composition and evolution of Earth's early atmosphere remains hazy.

  20. The Atmosphere of Venus

    NASA Technical Reports Server (NTRS)

    Hansen, J. E. (Editor)

    1975-01-01

    Topics considered at the conference included the dynamics, structure, chemistry, and evolution of the Venus atmosphere, as well as cloud physics and motion. Infrared, ultraviolet, and radio occultation methods of analysis are discussed, and atmospheric models are described.

  1. Uranus' Upper Atmosphere

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This computer enhancement of a Voyager 2 image, emphasizes the high-level haze in Uranus' upper atmosphere. Clouds are obscured by the overlying atmosphere.

    JPL manages and controls the Voyager project for NASA's Office of Space Science.

  2. The atmosphere of Mars

    NASA Technical Reports Server (NTRS)

    Barth, C. A.

    1974-01-01

    The atmosphere of Mars is essentially a pure carbon dioxide atmosphere that contains a small and seasonably varying amount of water vapor. A number of minor constituents which arise from the interactions of solar radiation with water vapor and carbon dioxide include carbon monoxide, atomic oxygen, molecular oxygen, ozone, and atomic hydrogen. At the surface of Mars the atmospheric pressure is less than one hundredth of the pressure at the surface of the earth. Extensive cloud systems appear on Mars. The structure of the lower Martian atmosphere is discussed together with variations in the lower atmosphere and the characteristics of the upper atmosphere. Reactions of photochemistry are considered along with the atmospheric escape and interactions between the atmosphere and the polar caps.

  3. Our shared atmosphere

    EPA Science Inventory

    Our atmosphere is a precious and fascinating resource, providing air to breath, shielding us from harmful ultraviolet radiation (UV), and maintaining a comfortable climate. Since the industrial revolution, people have significantly altered the composition of the atmosphere throu...

  4. Goddard Atmospheric Composition Data Center: Aura Data and Services in One Place

    NASA Technical Reports Server (NTRS)

    Leptoukh, G.; Kempler, S.; Gerasimov, I.; Ahmad, S.; Johnson, J.

    2005-01-01

    The Goddard Atmospheric Composition Data and Information Services Center (AC-DISC) is a portal to the Atmospheric Composition specific, user driven, multi-sensor, on-line, easy access archive and distribution system employing data analysis and visualization, data mining, and other user requested techniques for the better science data usage. It provides convenient access to Atmospheric Composition data and information from various remote-sensing missions, from TOMS, UARS, MODIS, and AIRS, to the most recent data from Aura OMI, MLS, HIRDLS (once these datasets are released to the public), as well as Atmospheric Composition datasets residing at other remote archive site.

  5. The atmosphere of Jupiter

    NASA Technical Reports Server (NTRS)

    Ingersoll, A. P.

    1976-01-01

    Current information on the neutral atmosphere of Jupiter is reviewed, with approximately equal emphasis on composition and thermal structure on one hand, and markings and dynamics on the other. Studies based on Pioneer 10 and 11 data are used to refine the atmospheric model. Data on the interior are reviewed for the information they provide on the deep atmosphere. The markings and dynamics are discussed with emphasis on qualitative relationships and analogies with phenomena in earth's atmosphere.

  6. Atmospheric Nitrogen Fluorescence Yield

    NASA Technical Reports Server (NTRS)

    Adams, J. H., Jr.; Christl, M. J.; Fountain, W. F.; Gregory, J. C.; Martens, K. U.; Sokolsky, Pierre; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    Several existing and planned experiments estimate the energies of ultra-high energy cosmic rays from air showers using the atmospheric nitrogen fluorescence. The nitrogen fluorescence yield from air shower electrons depends on the atmospheric composition. We will discuss the uncertainties in the fluorescence yield form electrons in the real atmosphere and describe a concept for a small balloon payload to measure the atmospheric fluorescence yield as a function of attitude.

  7. Hot Plasma from Solar Active Region Cores: a Test of AC and DC Coronal Heating Models?

    NASA Astrophysics Data System (ADS)

    Schmelz, J. T.; Asgari-Targhi, M.; Christian, G. M.; Dhaliwal, R. S.; Pathak, S.

    2015-06-01

    Direct current (DC) models of solar coronal heating invoke magnetic reconnection to convert magnetic free energy into heat, whereas alternating current (AC) models invoke wave dissipation. In both cases the energy is supplied by photospheric footpoint motions. For a given footpoint velocity amplitude, DC models predict lower average heating rates but greater temperature variability when compared to AC models. Therefore, evidence of hot plasma (T > 5 MK) in the cores of active regions could be one of the ways for current observations to distinguish between AC and DC models. We have analyzed data from the X-Ray Telescope (XRT) and the Atmospheric Imaging Assembly for 12 quiescent active region cores, all of which were observed in the XRT Be_thick channel. We did Differential Emission Measure (DEM) analysis and achieved good fits for each data set. We then artificially truncated the hot plasma of the DEM model at 5 MK and examined the resulting fits to the data. For some regions in our sample, the XRT intensities continued to be well-matched by the DEM predictions, even without the hot plasma. This truncation, however, resulted in unacceptable fits for the other regions. This result indicates that the hot plasma is present in these regions, even if the precise DEM distribution cannot be determined with the data available. We conclude that reconnection may be heating the hot plasma component of these active regions.

  8. HOT PLASMA FROM SOLAR ACTIVE REGION CORES: A TEST OF AC AND DC CORONAL HEATING MODELS?

    SciTech Connect

    Schmelz, J. T.; Christian, G. M.; Dhaliwal, R. S.; Pathak, S.; Asgari-Targhi, M.

    2015-06-20

    Direct current (DC) models of solar coronal heating invoke magnetic reconnection to convert magnetic free energy into heat, whereas alternating current (AC) models invoke wave dissipation. In both cases the energy is supplied by photospheric footpoint motions. For a given footpoint velocity amplitude, DC models predict lower average heating rates but greater temperature variability when compared to AC models. Therefore, evidence of hot plasma (T > 5 MK) in the cores of active regions could be one of the ways for current observations to distinguish between AC and DC models. We have analyzed data from the X-Ray Telescope (XRT) and the Atmospheric Imaging Assembly for 12 quiescent active region cores, all of which were observed in the XRT Be-thick channel. We did Differential Emission Measure (DEM) analysis and achieved good fits for each data set. We then artificially truncated the hot plasma of the DEM model at 5 MK and examined the resulting fits to the data. For some regions in our sample, the XRT intensities continued to be well-matched by the DEM predictions, even without the hot plasma. This truncation, however, resulted in unacceptable fits for the other regions. This result indicates that the hot plasma is present in these regions, even if the precise DEM distribution cannot be determined with the data available. We conclude that reconnection may be heating the hot plasma component of these active regions.

  9. Ac irreversibility line of bismuth-based high temperature superconductors

    SciTech Connect

    Mehdaoui, A.; Beille, J.; Berling, D.; Loegel, B.; Noudem, J.G.; Tournier, R.

    1997-09-01

    We discuss the magnetic properties of lead doped Bi-2223 bulk samples obtained through combined magnetic melt texturing and hot pressing (MMTHP). The ac complex susceptibility measurements are achieved over a broad ac field range (1 Oe{lt}h{sub ac}{lt}100 Oe) and show highly anisotropic properties. The intergranular coupling is improved in the direction perpendicular to the applied stress and magnetic field direction, and an intragranular loss peak is observed for the first time. A comparison is made with other bismuth-based compounds and it is shown that the MMTHP process shifts the ac irreversibility line (ac IL) toward higher fields. It is also shown that all the ac IL{close_quote}s for quasi 2D bismuth-based compounds show a nearly quadratic temperature dependence and deviate therefore strongly from the linear behavior observed in quasi 3D compounds and expected from a critical state model.{copyright} {ital 1997 Materials Research Society.}

  10. Electrothermally driven flows in ac electrowetting.

    PubMed

    García-Sánchez, Pablo; Ramos, Antonio; Mugele, Frieder

    2010-01-01

    Mixing within sessile drops can be enhanced by generating internal flow patterns using ac electrowetting. While for low ac frequencies, the flow patterns have been attributed to oscillations of the drop surface, we provide here the driving mechanism of the hitherto unexplained high-frequency flows. We show that: (1) the electric field in the liquid bulk becomes important, leading to energy dissipation due to Joule heating and a temperature increase of several degrees Celsius, and (2) the fluid flow at these frequencies is generated by electrothermal effect, i.e., gradients in temperature give rise to gradients in conductivity and permittivity, the electric field acting on these inhomogeneities induces an electrical body force that generates the flow. We solved numerically the equations for the electric, temperature and flow fields. The temperature is obtained from a convection-diffusion equation where Joule heating is introduced as a source term. From the solution of the electric field and the temperature, we compute the electrical force that acts as a body force in Stokes equations. Our numerical results agree with previous experimental observations.

  11. Cascading failures in ac electricity grids.

    PubMed

    Rohden, Martin; Jung, Daniel; Tamrakar, Samyak; Kettemann, Stefan

    2016-09-01

    Sudden failure of a single transmission element in a power grid can induce a domino effect of cascading failures, which can lead to the isolation of a large number of consumers or even to the failure of the entire grid. Here we present results of the simulation of cascading failures in power grids, using an alternating current (AC) model. We first apply this model to a regular square grid topology. For a random placement of consumers and generators on the grid, the probability to find more than a certain number of unsupplied consumers decays as a power law and obeys a scaling law with respect to system size. Varying the transmitted power threshold above which a transmission line fails does not seem to change the power-law exponent q≈1.6. Furthermore, we study the influence of the placement of generators and consumers on the number of affected consumers and demonstrate that large clusters of generators and consumers are especially vulnerable to cascading failures. As a real-world topology, we consider the German high-voltage transmission grid. Applying the dynamic AC model and considering a random placement of consumers, we find that the probability to disconnect more than a certain number of consumers depends strongly on the threshold. For large thresholds the decay is clearly exponential, while for small ones the decay is slow, indicating a power-law decay.

  12. Cascading failures in ac electricity grids

    NASA Astrophysics Data System (ADS)

    Rohden, Martin; Jung, Daniel; Tamrakar, Samyak; Kettemann, Stefan

    2016-09-01

    Sudden failure of a single transmission element in a power grid can induce a domino effect of cascading failures, which can lead to the isolation of a large number of consumers or even to the failure of the entire grid. Here we present results of the simulation of cascading failures in power grids, using an alternating current (AC) model. We first apply this model to a regular square grid topology. For a random placement of consumers and generators on the grid, the probability to find more than a certain number of unsupplied consumers decays as a power law and obeys a scaling law with respect to system size. Varying the transmitted power threshold above which a transmission line fails does not seem to change the power-law exponent q ≈1.6 . Furthermore, we study the influence of the placement of generators and consumers on the number of affected consumers and demonstrate that large clusters of generators and consumers are especially vulnerable to cascading failures. As a real-world topology, we consider the German high-voltage transmission grid. Applying the dynamic AC model and considering a random placement of consumers, we find that the probability to disconnect more than a certain number of consumers depends strongly on the threshold. For large thresholds the decay is clearly exponential, while for small ones the decay is slow, indicating a power-law decay.

  13. Amorphous force transducers in ac applications

    NASA Astrophysics Data System (ADS)

    Meydan, T.; Overshott, K. J.

    1982-11-01

    The high stress sensitivity and high yield stress properties of amorphous ribbon materials make them suitable for magnetic sensors and tranducer applications. Recently the authors have shown that ac systems eliminate the offset voltage and drift problems of the previously published dc systems. Further investigations proved that these transducers could be operated with a linear characteristic up to 1000 g in multiwrap toroidal configurations. The cause of the transducing behavior of the materials was proved to be variation of permeability with stress. It was previously suggested that the optimum operating frequency of the ac transducers is dependent on the physical configuration of the core. Further investigations have shown that the optimum operating frequency is linearly dependent on the amplitude of the input signal to the transducer. Double-core systems have been previously described in the literature where one core acts as a dummy core and the force is applied to the active core. The disadvantage of the double-core system is that aging of the active core changes the performance of the transducer by as much as 10%. A new system will be presented which uses an accurate analog memory to reduce the ageing effect to a fraction of one percent.

  14. AC impedance analysis of polypyrrole thin films

    NASA Technical Reports Server (NTRS)

    Penner, Reginald M.; Martin, Charles R.

    1987-01-01

    The AC impedance spectra of thin polypyrrole films were obtained at open circuit potentials from -0.4 to 0.4 V vs SCE. Two limiting cases are discussed for which simplified equivalent circuits are applicable. At very positive potentials, the predominantly nonfaradaic AC impedance of polypyrrole is very similar to that observed previously for finite porous metallic films. Modeling of the data with the appropriate equivalent circuit permits effective pore diameter and pore number densities of the oxidized film to be estimated. At potentials from -0.4 to -0.3 V, the polypyrrole film is essentially nonelectronically conductive and diffusion of polymer oxidized sites with their associated counterions can be assumed to be linear from the film/substrate electrode interface. The equivalent circuit for the polypyrrole film at these potentials is that previously described for metal oxide, lithium intercalation thin films. Using this model, counterion diffusion coefficients are determined for both semi-infinite and finite diffusion domains. In addition, the limiting low frequency resistance and capacitance of the polypyrrole thin fims was determined and compared to that obtained previously for thicker films of the polymer. The origin of the observed potential dependence of these low frequency circuit components is discussed.

  15. Transport AC Losses in Striated YBCO Coated Conductors (Postprint)

    DTIC Science & Technology

    2012-02-01

    AFRL-RZ-WP-TP-2012-0124 TRANSPORT AC LOSSES IN STRIATED YBCO COATED CONDUCTORS (POSTPRINT) G.A. Levin and P.N. Barnes Mechanical Energy...TRANSPORT AC LOSSES IN STRIATED YBCO COATED CONDUCTORS (POSTPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...2006. 14. ABSTRACT DC current-voltage characteristics and transport ac losses of striated and non-striated Y1Ba2Cu3O7-δ ( YBCO ) coated conductors

  16. Fabrication of alumina films with laminated structures by ac anodization.

    PubMed

    Segawa, Hiroyo; Okano, Hironaga; Wada, Kenji; Inoue, Satoru

    2014-02-01

    Anodization techniques by alternating current (ac) are introduced in this review. By using ac anodization, laminated alumina films are fabricated. Different types of alumina films consisting of 50-200 nm layers were obtained by varying both the ac power supply and the electrolyte. The total film thickness increased with an increase in the total charge transferred. The thickness of the individual layers increased with the ac voltage; however, the anodization time had little effect on the film thickness. The laminated alumina films resembled the nacre structure of shells, and the different morphologies exhibited by bivalves and spiral shells could be replicated by controlling the rate of increase of the applied potentials.

  17. Fabrication of alumina films with laminated structures by ac anodization

    NASA Astrophysics Data System (ADS)

    Segawa, Hiroyo; Okano, Hironaga; Wada, Kenji; Inoue, Satoru

    2014-02-01

    Anodization techniques by alternating current (ac) are introduced in this review. By using ac anodization, laminated alumina films are fabricated. Different types of alumina films consisting of 50-200 nm layers were obtained by varying both the ac power supply and the electrolyte. The total film thickness increased with an increase in the total charge transferred. The thickness of the individual layers increased with the ac voltage; however, the anodization time had little effect on the film thickness. The laminated alumina films resembled the nacre structure of shells, and the different morphologies exhibited by bivalves and spiral shells could be replicated by controlling the rate of increase of the applied potentials.

  18. Study of AC electrical conduction mechanisms in an epoxy polymer

    NASA Astrophysics Data System (ADS)

    Jilani, Wissal; Mzabi, Nissaf; Gallot-Lavallée, Olivier; Fourati, Najla; Zerrouki, Chouki; Zerrouki, Rachida; Guermazi, Hajer

    2015-11-01

    The AC conductivity of an epoxy resin was investigated in the frequency range 10^{-1} - 106 Hz at temperatures ranging from -100 to 120 °C. The frequency dependence of σ_{ac} was described by the law: σ_{ac}=ω \\varepsilon0\\varepsilon^''_{HN}+Aωs. The study of temperature variation of the exponent (s) reveals two conduction models: the AC conduction dependence upon temperature is governed by the small polaron tunneling mechanism (SPTM) at low temperature (-100 -60 °C) and the correlated barrier hopping (CHB) model at high temperature (80-120 °C).

  19. Nonisothermal Pluto atmosphere models

    SciTech Connect

    Hubbard, W.B.; Yelle, R.V.; Lunine, J.I. )

    1990-03-01

    The present thermal profile calculation for a Pluto atmosphere model characterized by a high number fraction of CH4 molecules encompasses atmospheric heating by solar UV flux absorption and conductive transport cooling to the surface of Pluto. The stellar occultation curve predicted for an atmosphere of several-microbar surface pressures (which entail the existence of a substantial temperature gradient close to the surface) agrees with observations and implies that the normal and tangential optical depth of the atmosphere is almost negligible. The minimum period for atmospheric methane depletion is calculated to be 30 years. 29 refs.

  20. Atmospheric Habitable Zones in Y Dwarf Atmospheres

    NASA Astrophysics Data System (ADS)

    Yates, Jack S.; Palmer, Paul I.; Biller, Beth; Cockell, Charles S.

    2017-02-01

    We use a simple organism lifecycle model to explore the viability of an atmospheric habitable zone (AHZ), with temperatures that could support Earth-centric life, which sits above an environment that does not support life. To illustrate our model, we use a cool Y dwarf atmosphere, such as WISE J085510.83–0714442.5, whose 4.5–5.2 μm spectrum shows absorption features consistent with water vapor and clouds. We allow organisms to adapt to their atmospheric environment (described by temperature, convection, and gravity) by adopting different growth strategies that maximize their chance of survival and proliferation. We assume a constant upward vertical velocity through the AHZ. We found that the organism growth strategy is most sensitive to the magnitude of the atmospheric convection. Stronger convection supports the evolution of more massive organisms. For a purely radiative environment, we find that evolved organisms have a mass that is an order of magnitude smaller than terrestrial microbes, thereby defining a dynamical constraint on the dimensions of life that an AHZ can support. Based on a previously defined statistical approach, we infer that there are of the order of 109 cool Y brown dwarfs in the Milky Way, and likely a few tens of these objects are within 10 pc from Earth. Our work also has implications for exploring life in the atmospheres of temperate gas giants. Consideration of the habitable volumes in planetary atmospheres significantly increases the volume of habitable space in the galaxy.

  1. Uncovering the Catalytic Direction of Chondroitin AC Exolyase

    PubMed Central

    Yin, Feng-Xin; Wang, Feng-Shan; Sheng, Ju-Zheng

    2016-01-01

    Glycosaminoglycans (GAGs) are polysaccharides that play vital functional roles in numerous biological processes, and compounds belonging to this class have been implicated in a wide variety of diseases. Chondroitin AC lyase (ChnAC) (EC 4.2.2.5) catalyzes the degradation of various GAGs, including chondroitin sulfate and hyaluronic acid, to give the corresponding disaccharides containing an Δ4-unsaturated uronic acid at their non-reducing terminus. ChnAC has been isolated from various bacteria and utilized as an enzymatic tool for study and evaluating the sequencing of GAGs. Despite its substrate specificity and the fact that its crystal structure has been determined to a high resolution, the direction in which ChnAC catalyzes the cleavage of oligosaccharides remain unclear. Herein, we have determined the structural cues of substrate depolymerization and the cleavage direction of ChnAC using model substrates and recombinant ChnAC protein. Several structurally defined oligosaccharides were synthesized using a chemoenzymatic approach and subsequently cleaved using ChnAC. The degradation products resulting from this process were determined by mass spectrometry. The results revealed that ChnAC cleaved the β1,4-glycosidic linkages between glucuronic acid and glucosamine units when these bonds were located on the reducing end of the oligosaccharide. In contrast, the presence of a GlcNAc-α-1,4-GlcA unit at the reducing end of the oligosaccharide prevented ChnAC from cleaving the GalNAc-β1,4-GlcA moiety located in the middle or at the non-reducing end of the chain. These interesting results therefore provide direct proof that ChnAC cleaves oligosaccharide substrates from their reducing end toward their non-reducing end. This conclusion will therefore enhance our collective understanding of the mode of action of ChnAC. PMID:26742844

  2. AcMNPV ac143 (odv-e18) is essential for mediating budded virus production and is the 30th baculovirus core gene.

    PubMed

    McCarthy, Christina B; Theilmann, David A

    2008-05-25

    Autographa californica multiple nucleopolyhedrovirus (AcMNPV) ac143 (odv-e18) is a late gene that encodes for a predicted 9.6 kDa structural protein that locates to the occlusion derived viral envelope and viral induced intranuclear microvesicles [Braunagel, S.C., He, H., Ramamurthy, P., and Summers, M.D. (1996). Transcription, translation, and cellular localization of three Autographa californica nuclear polyhedrosis virus structural proteins: ODV-E18, ODV-E35, and ODV-EC27. Virology 222, 100-114.]. In this study we demonstrate that ac143 is actually a previously unrecognized core gene and that it is essential for mediating budded virus production. To examine the role of ac143 in the baculovirus life cycle, we used the AcMNPV bacmid system to generate an ac143 knockout (KO) virus (AcBAC(ac142)(REP-ac143KO)). Fluorescence and light microscopy showed that infection by AcBAC(ac142)(REP-ac143KO) is limited to a single cell and titration assays confirmed that AcBAC(ac142)(REP-ac143KO) was unable to produce budded virus (BV). Progression to very late phases of the viral infection was evidenced by the development of occlusion bodies in the nuclei of transfected cells. This correlated with the fact that viral DNA replication was unaffected in AcBAC(ac142)(REP-ac143KO) transfected cells. The entire ac143 promoter, which includes three late promoter motifs, is contained within the ac142 open reading frame. Different deletion mutants of this region showed that the integrity of the ac142-ac143 core gene cluster was required for the bacmids to display wild-type patterns of viral replication, BV production and RNA transcription.

  3. AcMNPV ac143 (odv-e18) is essential for mediating budded virus production and is the 30th baculovirus core gene

    SciTech Connect

    McCarthy, Christina B.; Theilmann, David A.

    2008-05-25

    Autographa californica multiple nucleopolyhedrovirus (AcMNPV) ac143 (odv-e18) is a late gene that encodes for a predicted 9.6 kDa structural protein that locates to the occlusion derived viral envelope and viral induced intranuclear microvesicles [Braunagel, S.C., He, H., Ramamurthy, P., and Summers, M.D. (1996). Transcription, translation, and cellular localization of three Autographa californica nuclear polyhedrosis virus structural proteins: ODV-E18, ODV-E35, and ODV-EC27. Virology 222, 100-114.]. In this study we demonstrate that ac143 is actually a previously unrecognized core gene and that it is essential for mediating budded virus production. To examine the role of ac143 in the baculovirus life cycle, we used the AcMNPV bacmid system to generate an ac143 knockout (KO) virus (AcBAC{sup ac142REP-ac143KO}). Fluorescence and light microscopy showed that infection by AcBAC{sup ac142REP-ac143KO} is limited to a single cell and titration assays confirmed that AcBAC{sup ac142REP-ac143KO} was unable to produce budded virus (BV). Progression to very late phases of the viral infection was evidenced by the development of occlusion bodies in the nuclei of transfected cells. This correlated with the fact that viral DNA replication was unaffected in AcBAC{sup ac142REP-ac143KO} transfected cells. The entire ac143 promoter, which includes three late promoter motifs, is contained within the ac142 open reading frame. Different deletion mutants of this region showed that the integrity of the ac142-ac143 core gene cluster was required for the bacmids to display wild-type patterns of viral replication, BV production and RNA transcription.

  4. Demonstration of an ac Josephson junction laser

    NASA Astrophysics Data System (ADS)

    Cassidy, M. C.; Bruno, A.; Rubbert, S.; Irfan, M.; Kammhuber, J.; Schouten, R. N.; Akhmerov, A. R.; Kouwenhoven, L. P.

    2017-03-01

    Superconducting electronic devices have reemerged as contenders for both classical and quantum computing due to their fast operation speeds, low dissipation, and long coherence times. An ultimate demonstration of coherence is lasing. We use one of the fundamental aspects of superconductivity, the ac Josephson effect, to demonstrate a laser made from a Josephson junction strongly coupled to a multimode superconducting cavity. A dc voltage bias applied across the junction provides a source of microwave photons, and the circuit’s nonlinearity allows for efficient down-conversion of higher-order Josephson frequencies to the cavity’s fundamental mode. The simple fabrication and operation allows for easy integration with a range of quantum devices, allowing for efficient on-chip generation of coherent microwave photons at low temperatures.

  5. Public Understanding of Chemistry, ACS National Meeting

    NASA Astrophysics Data System (ADS)

    Gettys, Nancy S.

    2000-06-01

    Three public events for area school-aged children were held on Saturday, March 25, 2000, prior to the opening of the 219th National Meeting of the American Chemical Society. All took place at the Moscone Convention Center in downtown San Francisco. The photographs tell the story: the programs were successful and a good time was had by all. Readers may be encouraged to try these ideas in their own area. If so, the local organizers of Carver Kidvention have additional information at www.scvacs.org/Carver/index.html or contact Howard Peters (Santa Clara Valley Section, ACS), peters4pa@aol.com. Additional photos of the Kidvention event may also be seen as supplemental material.

  6. Dielectric relaxation in AC powder electroluminescent devices

    NASA Astrophysics Data System (ADS)

    Zhang, Shuai; Su, Haibin; Tan, Chuan Seng; Wong, Terence Kin Shun; Teo, Ronnie Jin Wah

    2017-01-01

    The dielectric properties of AC powder electroluminescent devices were measured and analyzed using complex impedance spectroscopy to determine the relaxation processes occurring within the devices. The relaxation processes identified were ascribed to the electrode polarization caused by ion accumulation at the electrode/resin interfaces, the Maxwell-Wagner-Sillars effects at the (ZnS or BaTiO3) particle/resin interfaces, and the dipolar reorientation of polymer chains in the resin matrix. Each relaxation process was represented by its corresponding equivalent circuit component. Space charge polarization at the electrodes were represented by a Warburg element, a resistor, and a constant phase element. The resin matrix, ZnS/resin and BaTiO3/resin interfaces could each be modeled by a resistor and a capacitor in parallel. The simulated equivalent circuits for three different printed structures showed good fitting with their experimental impedance results.

  7. Advanced ac powertrain for electric vehicles

    SciTech Connect

    Slicker, J.M.; Kalns, L.

    1985-01-01

    The design of an ac propulsion system for an electric vehicle includes a three-phase induction motor, transistorized PWM inverter/battery charger, microprocessor-based controller, and two-speed automatic transaxle. This system was built and installed in a Mercury Lynx test bed vehicle as part of a Department of Energy propulsion system development program. An integral part of the inverter is a 4-kw battery charger which utilizes one of the bridge transistors. The overall inverter strategy for this configuration is discussed. The function of the microprocessor-based controller is described. Typical test results of the total vehicle and each of its major components are given, including system efficiencies and test track performance results.

  8. Fuzzy efficiency optimization of AC induction motors

    NASA Technical Reports Server (NTRS)

    Jani, Yashvant; Sousa, Gilberto; Turner, Wayne; Spiegel, Ron; Chappell, Jeff

    1993-01-01

    This paper describes the early states of work to implement a fuzzy logic controller to optimize the efficiency of AC induction motor/adjustable speed drive (ASD) systems running at less than optimal speed and torque conditions. In this paper, the process by which the membership functions of the controller were tuned is discussed and a controller which operates on frequency as well as voltage is proposed. The membership functions for this dual-variable controller are sketched. Additional topics include an approach for fuzzy logic to motor current control which can be used with vector-controlled drives. Incorporation of a fuzzy controller as an application-specific integrated circuit (ASIC) microchip is planned.

  9. Boston ACS Meeting, Chemical Education Program

    NASA Astrophysics Data System (ADS)

    Wildeman, Thomas R.; Torre, Frank; Smist, Julianne

    1998-11-01

    For those of us who had not been to Boston since the last ACS meeting it was surprising to see how vibrant the city was. The shops, restaurants, parks, and other attractions throughout the large inner city area made the meeting most enjoyable. Again, our banquet cruise of the harbor was blessed with excellent weather. The ship went out far enough so that we landlocked people could feel the waves. The entire program had a celebratory tone-two sessions marking the 70th birthday of Glenn Crosby, a memorial symposium celebrating the teaching innovations of Hubert Alyea, and the 75th anniversary of the Journal of Chemical Education (>p 1360). Content issues in upper division chemistry courses as well as general chemistry took up a large portion of the program. Some of the symposia are discussed in this article.

  10. ACS Internal CTE Monitor and Short Darks

    NASA Astrophysics Data System (ADS)

    Ogaz, Sara

    2012-10-01

    This is a continuation of Program 12386 and is to be executed once a cycle for internal CTE and short darks, respectively.INTERNAL CTE MONITOR:The charge transfer efficiency {CTE} of the ACS CCD detectors will decline as damage due to on-orbit radiation exposure accumulates. This degradation will be monitored once a cycle to determine the useful lifetime of the CCDs. All the data for this program is acquired using internal targets {lamps} only, so all of the exposures should be taken during Earth occultation time {but not during SAA passages}. This program emulates the ACS pre-flight ground calibration and post-launch SMOV testing {program 8948}, so that results from each epoch can be directly compared. Extended Pixel Edge Response {EPER} data will be obtained over a range of signal levels for the Wide Field Channel {WFC}. The signal levels are 125, 500, 1620, 5000, 10000, and 60000 electrons at gain 2.Since Cycle 18, this monitoring program was reduced {compared to 11881} considering that there is also an external CTE monitoring program.SHORT DARKS:To improve the pixel-based CTE model at signals below 10 DN, short dark frames are needed to obtain a statistically useful sample of clean, warm pixel trails. This program obtains a set of dark frames for each of the following exposure times: 66 s {60 s for some subarrays} and 339 s. These short darks and the 1040 s darks obtained from the CCD Daily Monitor will sample warm and hot pixels over logarithmically increasing brightness. Subarray short darks were newly added in Cycle 19 to study CTE tails in different subarray readout modes.

  11. ACS Internal CTE Monitor and Short Darks

    NASA Astrophysics Data System (ADS)

    Ogaz, Sara

    2013-10-01

    This is a continuation of Program 13156 and is to be executed once a cycle for internal CTE and short darks, respectively.INTERNAL CTE MONITOR:The charge transfer efficiency {CTE} of the ACS CCD detectors will decline as damage due to on-orbit radiation exposure accumulates. This degradation will be monitored once a cycle to determine the useful lifetime of the CCDs. All the data for this program is acquired using internal targets {lamps} only, so all of the exposures should be taken during Earth occultation time {but not during SAA passages}. This program emulates the ACS pre-flight ground calibration and post-launch SMOV testing {program 8948}, so that results from each epoch can be directly compared. Extended Pixel Edge Response {EPER} data will be obtained over a range of signal levels for the Wide Field Channel {WFC}. The signal levels are 125, 500, 1620, 5000, 10000, and 60000 electrons at gain 2.Since Cycle 18, this monitoring program was reduced {compared to 11881} considering that there is also an external CTE monitoring program.SHORT DARKS:To improve the pixel-based CTE model at signals below 10 DN, short dark frames are needed to obtain a statistically useful sample of clean, warm pixel trails. This program obtains a set of dark frames for each of the following exposure times: 66 s {60 s for some subarrays} and 339 s. These short darks and the 1040 s darks obtained from the CCD Daily Monitor will sample warm and hot pixels over logarithmically increasing brightness. Subarray short darks were added in Cycle 19 to study CTE tails in different subarray readout modes.

  12. ACS Internal CTE Monitor and Short Darks

    NASA Astrophysics Data System (ADS)

    Lian Lim, Pey

    2010-09-01

    INTERNAL CTE MONITOR:The charge transfer efficiency {CTE} of the ACS CCD detectors will decline as damage due to on-orbit radiation exposure accumulates. This degradation will be monitored once a cycle to determine the useful lifetime of the CCDs. All the data for this program is acquired using internal targets {lamps} only, so all of the exposures should be taken during Earth occultation time {but not during SAA passages}. This program emulates the ACS pre-flight ground calibration and post-launch SMOV testing {program 8948}, so that results from each epoch can be directly compared. Extended Pixel Edge Response {EPER} data will be obtained over a range of signal levels for the Wide Field Channel {WFC}. The signal levels are 125, 500, 1620, 5000, 10000, and 60000 electrons at gain 2.In Cycle 18, this monitoring program has been reduced {compared to 11881} considering that there is also an external CTE monitoring program. High Resolution Camera {HRC} is not available for observations. First Pixel Response {FPR} exposures are removed because they only provide serial CTE for WFC, which is not that useful. Pseudo-bias exposures are removed because they are not used. Signal levels 300, 700, 1000, 30000, and 45000.electrons are removed to reduce total orbits. Number of exposures per setting are reduced to 1 only. Amps BC are removed since amp dependence is not an issue for EPER.SHORT DARKS:To improve the pixel-based CTE model at signals below 10 DN, short dark frames are needed to obtain a statistically useful sample of clean, warm pixel trails. This program obtains 9 dark frames for each of the following exposure times: 33 s, 100 s, and 339 s. These short darks and the 1000 s darks obtained from the CCD Daily Monitor will sample warm and hot pixels over logarithmically increasing brightness.This is a continuation of Program 12327 and is to be executed once a cycle.

  13. ACS Internal CTE Monitor and Short Darks

    NASA Astrophysics Data System (ADS)

    Lian Lim, Pey

    2011-10-01

    This is a continuation of Program 12386 and is to be executed once a cycle for internal CTE and short darks, respectively.INTERNAL CTE MONITOR:The charge transfer efficiency {CTE} of the ACS CCD detectors will decline as damage due to on-orbit radiation exposure accumulates. This degradation will be monitored once a cycle to determine the useful lifetime of the CCDs. All the data for this program is acquired using internal targets {lamps} only, so all of the exposures should be taken during Earth occultation time {but not during SAA passages}. This program emulates the ACS pre-flight ground calibration and post-launch SMOV testing {program 8948}, so that results from each epoch can be directly compared. Extended Pixel Edge Response {EPER} data will be obtained over a range of signal levels for the Wide Field Channel {WFC}. The signal levels are 125, 500, 1620, 5000, 10000, and 60000 electrons at gain 2.Since Cycle 18, this monitoring program was reduced {compared to 11881} considering that there is also an external CTE monitoring program.SHORT DARKS:To improve the pixel-based CTE model at signals below 10 DN, short dark frames are needed to obtain a statistically useful sample of clean, warm pixel trails. This program obtains a set of dark frames for each of the following exposure times: 66 s {60 s for some subarrays} and 339 s. These short darks and the 1040 s darks obtained from the CCD Daily Monitor will sample warm and hot pixels over logarithmically increasing brightness. Subarray short darks are newly added in Cycle 19 to study CTE tails in different subarray readout modes.

  14. Wind-powered asynchronous AC/DC/AC converter system. [for electric power supply regulation

    NASA Technical Reports Server (NTRS)

    Reitan, D. K.

    1973-01-01

    Two asynchronous ac/dc/ac systems are modelled that utilize wind power to drive a variable or constant hertz alternator. The first system employs a high power 60-hertz inverter tie to the large backup supply of the power company to either supplement them from wind energy, storage, or from a combination of both at a preset desired current; rectifier and inverter are identical and operate in either mode depending on the silicon control rectifier firing angle. The second system employs the same rectification but from a 60-hertz alternator arrangement; it provides mainly dc output, some sinusoidal 60-hertz from the wind bus and some high harmonic content 60-hertz from an 800-watt inverter.

  15. 24 CFR Appendices A-C to Subtitle A - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false A Appendices A-C to Subtitle A Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development Appendices A-C to Subtitle A...

  16. 24 CFR Appendixes A-C to Subtitle A - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false A Appendixes A-C to Subtitle A Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development Appendixes A-C to Subtitle A...

  17. 24 CFR Appendices A-C to Subtitle A - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false A Appendices A-C to Subtitle A Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development Appendices A-C to Subtitle A...

  18. 24 CFR Appendices A-C to Subtitle A - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false A Appendices A-C to Subtitle A Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development Appendices A-C to Subtitle A...

  19. 24 CFR Appendices A-C to Subtitle A - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false A Appendices A-C to Subtitle A Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development Appendices A-C to Subtitle A...

  20. 21 CFR 880.5500 - AC-powered patient lift.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Therapeutic Devices § 880.5500 AC-powered patient lift. (a) Identification. An AC-powered lift is an electrically powered device either fixed or mobile, used to lift and transport patients in the horizontal or...

  1. Undergraduate Chemistry Education: Report of an ACS Presidential Symposium

    ERIC Educational Resources Information Center

    Polik, William F.

    2006-01-01

    The American Chemical Society (ACS) Presidential Symposium, Envisioning Undergraduate Chemistry Education in 2015 was organized by the ACS Committee on Professional Training (CPT), in response to the challenge to envision the chemistry enterprise in 2015. The need for more diverse role models at all levels is emphasized, including high school…

  2. 40 CFR Appendixes A-C to Part 403 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 30 2013-07-01 2012-07-01 true A Appendixes A-C to Part 403 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GENERAL PRETREATMENT REGULATIONS FOR EXISTING AND NEW SOURCES OF POLLUTION Appendixes A-C to Part 403...

  3. 34 CFR Appendices A-C to Part 682 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 4 2014-07-01 2014-07-01 false A Appendices A-C to Part 682 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION (CONTINUED) FEDERAL FAMILY EDUCATION LOAN (FFEL) PROGRAM Appendices A-C to Part 682...

  4. Operation of AC Adapters Visualized Using Light-Emitting Diodes

    ERIC Educational Resources Information Center

    Regester, Jeffrey

    2016-01-01

    A bridge rectifier is a diamond-shaped configuration of diodes that serves to convert alternating current(AC) into direct current (DC). In our world of AC outlets and DC electronics, they are ubiquitous. Of course, most bridge rectifiers are built with regular diodes, not the light-emitting variety, because LEDs have a number of disadvantages. For…

  5. 40 CFR Appendixes A-C to Part 403 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true A Appendixes A-C to Part 403 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GENERAL PRE-TREAT-MENT REGULATIONS FOR EXIST-ING AND NEW SOURCES OF POLLUTION Appendixes A-C to Part 403...

  6. ACS Committee on Professional Training 1986 Annual Report.

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1987

    1987-01-01

    Presents data on the number of bachelor's, master's, and Ph.D. degrees in chemistry from institutions whose programs are approved by the American Chemical Society (ACS). Reviews the programs and activities endorsed by the ACS Board of Directors in April, 1986. (ML)

  7. 40 CFR Appendixes A-C to Part 403 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 29 2011-07-01 2009-07-01 true A Appendixes A-C to Part 403 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GENERAL PRE-TREAT-MENT REGULATIONS FOR EXIST-ING AND NEW SOURCES OF POLLUTION Appendixes A-C to Part 403...

  8. Solid-state ac-to-dc converter

    NASA Technical Reports Server (NTRS)

    Monroe, C. M.

    1970-01-01

    Converter uses solid-state ac-to-dc rectification circuitry, filter circuitry, a tuned transformer, ac chopper circuitry, and an automatic current-control network. It has a dc power source which operates from 5 to 100 percent load at a 72 to 94 input to output efficiency.

  9. Electrostatic coalescence system with independent AC and DC hydrophilic electrodes

    DOEpatents

    Hovarongkura, A. David; Henry, Jr., Joseph D.

    1981-01-01

    An improved electrostatic coalescence system is provided in which independent AC and DC hydrophilic electrodes are employed to provide more complete dehydration of an oil emulsion. The AC field is produced between an AC electrode array and the water-oil interface wherein the AC electrode array is positioned parallel to the interface which acts as a grounded electrode. The emulsion is introduced into the AC field in an evenly distributed manner at the interface. The AC field promotes drop-drop and drop-interface coalescence of the water phase in the entering emulsion. The continuous oil phase passes upward through the perforated AC electrode array and enters a strong DC field produced between closely spaced DC electrodes in which small dispersed droplets of water entrained in the continuous phase are removed primarily by collection at hydrophilic DC electrodes. Large droplets of water collected by the electrodes migrate downward through the AC electrode array to the interface. All phase separation mechanisms are utilized to accomplish more complete phase separation.

  10. Precursors of Short GRBs Registered by SPI-ACS/INTEGRAL

    NASA Astrophysics Data System (ADS)

    Minaev, P.; Pozanenko, A.

    2016-10-01

    We have searched for precursors in light curves of short gamma-ray bursts registered by SPI-ACS/INTEGRAL in 2002-2014. The portion of short bursts with precursor activity will be less than 0.4% from all short bursts registered by SPI-ACS.

  11. Distribution of Unlinked Receptor Sites for Transposed Ac Elements from the Bz-M2(ac) Allele in Maize

    PubMed Central

    Dooner, H. K.; Belachew, A.; Burgess, D.; Harding, S.; Ralston, M.; Ralston, E.

    1994-01-01

    We have shown before that the Ac element from the maize bz-m2(Ac) allele, located in the short arm of chromosome 9 (9S), transposes preferentially to sites that are linked to the bz donor locus. Yet, about half of the Ac transpositions recovered from bz-m2(Ac) are in receptor sites not linked to the donor locus. In this study, we have analyzed the distribution of those unlinked receptor sites. Thirty-seven transposed Ac (trAc) elements that recombined independently of the bz locus were mapped using a set of wx reciprocal translocations. We found that the distribution of unlinked receptor sites for trAs was not random. Ten trAcs mapped to 9L, i.e., Ac had transposed to sites physically, if not genetically, linked to the donor site. Among chromosomes other than 9, the Ac element of bz-m2(Ac) appeared to have transposed preferentially to certain chromosomes, such as 5 and 7, but infrequently to others, such as 1, the longest chromosome in the maize genome. The seven trAc elements in chromosome 5 were mapped relative to markers in 5S and 5L and localized to both arms of 5. We also investigated the transposition of Ac to the homolog of the donor chromosome. We found that Ac rarely transposes from bz-m2(Ac) to the homologous chromosome 9. The clustering of Ac receptor sites around the donor locus has been taken to mean that a physical association between the donor site and nearby receptor sites occurs during transposition. The preferential occurrence of 9L among chromosomes harboring unlinked receptor sites would be expected according to this model, since sites in 9L would tend to be physically closer to 9S than sites in other chromosomes. The nonrandom pattern seen among the remaining chromosomes could reflect an underlying nuclear architecture, i.e., an ordering of the chromosomes in the interphase nucleus, as suggested from previous cytological observations. PMID:8138163

  12. Dynamic evolution of coherent vortex dipole in atmospheric turbulence

    NASA Astrophysics Data System (ADS)

    Li, Jinhong; Zeng, Jun

    2017-01-01

    The analytical expression for the cross-spectral density function of Gaussian Schell-model (GSM) beams with coherent vortex dipole (CVD) propagating through atmospheric turbulence is derived, which enables us to study the evolution process of CVD propagating through atmospheric turbulence, where the influences of the beams parameters and atmospheric turbulence parameters on the ratio of critical off-axis distance to the waist width are stressed. It shows that the evolution process of the CVD depends on the off-axis distance. The larger the off-axis distance is, the more the number of CVD is. When the off-axis distance is zero, the position of coherent vortices with positive and negative topological charge of CVD propagating through atmospheric turbulence is always symmetry. When the off-axis distance is big enough, compared with the situation at source plane, the orientation of the positive coherent vortex of inherent CVD and negative coherent vortex of that rotates 180° in the far field. The larger the structure constant and the waist width are, as well as the smaller the spatial correlation length and the inner scale are, the smaller the ratio ac/w0 is. Besides, the ratio ac/w0 will no longer change when the spatial correlation length or the inner scale increases to a certain value, whereas the outer scale has no effect on the ratio.

  13. Design development and test: Two-gas atmosphere control subsystem

    NASA Technical Reports Server (NTRS)

    Jackson, J. K.

    1974-01-01

    An atmosphere control subsystem (ACS) was developed for NASA-IBJSC which is designed to measure the major atmospheric constituents in the manned cabin of the space shuttle orbiter and control the addition of oxygen and nitrogen to maintain the partial pressures of these gases within very close limits. The ACS includes a mass spectrometer sensor (MSS) which analyzes the atmosphere of a shuttle vehicle pressurized cabin, and an electronic control assembly (ECA). The MSS was built and tested to meet the requirements for flight equipment for the M-171 Metabolic Analyzer experiment for the Skylab flight program. The instrument analyzes an atmospheric gas sample and produces continuous 0-5 vdc analog signals proportional to the partial pressures of H2, O2, N2, H2O, CO2 and total hydrocarbons having a m/e ratio between 50 and 120. It accepts signals from the MSS proportional to the partial pressures of N2 and O2 and controls the supply of these gases to the closed cabin.

  14. Photochemistry in planetary atmospheres

    NASA Technical Reports Server (NTRS)

    Levine, J. S.; Graedel, T. E.

    1981-01-01

    Widely varying paths of evolutionary history, atmospheric processes, solar fluxes, and temperatures have produced vastly different planetary atmospheres. The similarities and differences between the earth atmosphere and those of the terrestrial planets (Venus and Mars) and of the Jovian planets are discussed in detail; consideration is also given to the photochemistry of Saturn, Uranus, Pluto, Neptune, Titan, and Triton. Changes in the earth's ancient atmosphere are described, and problems of interest in the earth's present troposphere are discussed, including the down wind effect, plume interactions, aerosol nucleation and growth, acid rain, and the fate of terpenes. Temperature fluctuations in the four principal layers of the earth's atmosphere, predicted decreases in the ozone concentration as a function of time, and spectra of particles in the earth's upper atmosphere are also presented. Finally, the vertical structure of the Venus cloud system and the thermal structure of the Jovian planets are shown graphically.

  15. Pluto's atmosphere near perihelion

    SciTech Connect

    Trafton, L.M. )

    1989-11-01

    A recent stellar occultation has confirmed predictions that Pluto has an atmosphere which is sufficiently thick to uniformly envelope the planet and to extend far above the surface. Pluto's atmosphere consists of methane and perhaps other volatile gases at temperatures below their freezing points; it should regulate the surface temperature of its volatile ices to a globally uniform value. As Pluto approaches and passes through perihelion, a seasonal maximum in the atmospheric bulk and a corresponding minimum in the exposed volatile ice abundance is expected to occur. The lag in maximum atmospheric bulk relative to perihelion will be diagnostic of the surface thermal properties. An estimate of Pluto's atmospheric bulk may result if a global darkening (resulting from the disappearance of the seasonally deposited frosts) occurs before the time of maximum atmospheric bulk. The ice deposited shortly after perihelion may be diagnostic of the composition of Pluto's volatile reservoir.

  16. Successful enrichment of the ubiquitous freshwater acI Actinobacteria.

    PubMed

    Garcia, Sarahi L; McMahon, Katherine D; Grossart, Hans-Peter; Warnecke, Falk

    2014-02-01

    Actinobacteria of the acI lineage are often the numerically dominant bacterial phylum in surface freshwaters, where they can account for > 50% of total bacteria. Despite their abundance, there are no described isolates. In an effort to obtain enrichment of these ubiquitous freshwater Actinobacteria, diluted freshwater samples from Lake Grosse Fuchskuhle, Germany, were incubated in 96-well culture plates. With this method, a successful enrichment containing high abundances of a member of the lineage acI was established. Phylogenetic classification showed that the acI Actinobacteria of the enrichment belonged to the acI-B2 tribe, which seems to prefer acidic lakes. This enrichment grows to low cell densities and thus the oligotrophic nature of acI-B2 was confirmed.

  17. Sustainable AC/AC hybrid electrochemical capacitors in aqueous electrolyte approaching the performance of organic systems

    NASA Astrophysics Data System (ADS)

    Abbas, Qamar; Babuchowska, Paulina; Frąckowiak, Elżbieta; Béguin, François

    2016-09-01

    A high energy hybrid AC/AC electrochemical capacitor has been realized in aqueous Li2SO4+KI electrolyte mixture. Owing to the redox processes associated with the 2I-/I2 system, the positive electrode operates in narrow potential range and displays high capacity. During prolonged potentiostatic floating at 1.6 V, the hybrid cell demonstrates remarkably stable capacitance and resistance. Analyses by temperature programmed desorption after floating at 1.6 V proved that oxidation of the positive AC electrode is prevented by the use of Li2SO4+KI, which enables the maximum potential of this electrode to be shifted below the water oxidation potential. When charged at 0.2 A g-1 up to U = 1.6 V, the hybrid cell displays a high capacitance of 75 F g-1 (300 F g-1 per mass of one electrode) compared to 47 F g-1 (188 F g-1 per mass of one electrode) for a symmetric cell in Li2SO4. At 0.2 A g-1 up to 1.6 V, the hybrid capacitor in Li2SO4+KI displays an energy density of 26 Wh kg-1 which approaches the energy density of 30.9 Wh kg-1 measured when the same carbon is implemented in a capacitor using TEABF4/ACN electrolyte and charged up to 2.5 V.

  18. HVDC-AC system interaction from AC harmonics. Volume 1. Harmonic impedance calculations. Final report

    SciTech Connect

    Breuer, G D; Chow, J H; Lindh, C B; Miller, N W; Numrich, F H; Price, W W; Turner, A E; Whitney, R R

    1982-09-01

    Improved methods are needed to characterize ac system harmonic behavior for ac filter design for HVDC systems. The purpose of this General Electric Company RP1138 research is to evaluate the present filter design practice and to investigate methods for calculating system harmonic impedances. An overview of ac filter design for HVDC systems and a survey of literature related to filter design have been performed. Two methods for calculating system harmonic impedances have been investigated. In the measurement method, an instrumentation system for measuring system voltage and current has been assembled. Different schemes of using the measurements to calculate system harmonic impedances have been studied. In the analytical method, a procedure to include various operating conditions has been proposed. Computer programs for both methods have been prepared, and the results of the measurement and analytical methods analyzed. A conclusion of the project is that the measurement and analytical methods both provided reasonable results. There are correlations between the measured and analytical results for most harmonics, although there are discrepancies between the assumptions used in the two methods. A sensitivity approach has been proposed to further correlate the results. From the results of the analysis, it is recommended that both methods should be tested further. For the measurement method, more testing should be done to cover different system operating conditions. In the analytical method, more detailed models for representing system components should be studied. In addition, alternative statistical and sensitivity approaches should be attempted.

  19. Oscillations in stellar atmospheres

    NASA Technical Reports Server (NTRS)

    Costa, A.; Ringuelet, A. E.; Fontenla, J. M.

    1989-01-01

    Atmospheric excitation and propagation of oscillations are analyzed for typical pulsating stars. The linear, plane-parallel approach for the pulsating atmosphere gives a local description of the phenomenon. From the local analysis of oscillations, the minimum frequencies are obtained for radially propagating waves. The comparison of the minimum frequencies obtained for a variety of stellar types is in good agreement with the observed periods of the oscillations. The role of the atmosphere in the globar stellar pulsations is thus emphasized.

  20. Atmospheric merger in London

    NASA Astrophysics Data System (ADS)

    At the invitation of Imperial College, the Laboratory for Planetary Atmospheres, University College London, will be integrated in August with the Atmospheric Physics Group to form a single teaching and research unit. The new group, to be located at Imperial College, will be headed by Garry Hunt.The new group will possess a balanced research program in the observational and interpretative aspects of atmospheric physics. The existing Imperial College group actively researches cumulonimbus dynamics and climate modeling.

  1. Sources of atmospheric ammonia

    NASA Technical Reports Server (NTRS)

    Harriss, R. C.; Michaels, J. T.

    1982-01-01

    The information available on factors that influence emissions from the principal societal sources of ammonia to the atmosphere, namely combustion processes, volatilization of farm animal wastes, and volatilization of fertilizers, is reviewed. Emission factors are established for each major source of atmospheric ammonia. The factors are then multiplied by appropriate source characterization descriptors to obtain calculated fluxes of ammonia to the atmosphere on a state-by-state basis for the United States.

  2. Geomagnetic and atmospheric effects

    NASA Astrophysics Data System (ADS)

    Stoker, P. H.

    1983-08-01

    Geomagnetic and atmospheric processes affecting cosmic-ray earthbound spectrometry are analyzed. The topics discussed include: cutoff rigidities and asymptotic directions; cosmic ray secondaries in the atmosphere and magnetosphere; neutron counters without lead and neutron monitors; and coupling coefficients/yield functions and response functions of cosmic ray detectors. Theoretical simulations of the atmosphere and geomagnetism are presented, taking into account such factors as geomagnetic ring currents and meteorological effects. Diagrams and cutoff rigidity contours are included.

  3. Atmospheric density models

    NASA Technical Reports Server (NTRS)

    Mueller, A. C.

    1977-01-01

    An atmospheric model developed by Jacchia, quite accurate but requiring a large amount of computer storage and execution time, was found to be ill-suited for the space shuttle onboard program. The development of a simple atmospheric density model to simulate the Jacchia model was studied. Required characteristics including variation with solar activity, diurnal variation, variation with geomagnetic activity, semiannual variation, and variation with height were met by the new atmospheric density model.

  4. Atmospheres from Within

    NASA Technical Reports Server (NTRS)

    Morgan, Thomas; Abshire, James; Clancy, Todd; Fry, Ghee; Gustafson, Bo; Hecht, Michael; Kostiuk, Theodor; Rall, Jonathan; Reuter, Dennis; Sheldon, Robert

    1996-01-01

    In this review of atmospheric investigations from planetary surfaces, a wide variety of measurement and instrument techniques relevant to atmospheric studies from future planetary lander missions are discussed. The diversity of planetary surface environments within the solar system precludes complete or highly specific coverage, but lander investigations for Mars and cometary missions are presented as specific cases that represent the broad range of atmospheric-surface boundaries and that also correspond to high priority goals for future national and international lander missions.

  5. Global Atmospheric Aerosol Modeling

    NASA Technical Reports Server (NTRS)

    Hendricks, Johannes; Aquila, Valentina; Righi, Mattia

    2012-01-01

    Global aerosol models are used to study the distribution and properties of atmospheric aerosol particles as well as their effects on clouds, atmospheric chemistry, radiation, and climate. The present article provides an overview of the basic concepts of global atmospheric aerosol modeling and shows some examples from a global aerosol simulation. Particular emphasis is placed on the simulation of aerosol particles and their effects within global climate models.

  6. An Ac transposon system based on maize chromosome 4S for isolating long-distance-transposed Ac tags in the maize genome.

    PubMed

    Wang, Fei; Li, Zhaoying; Fan, Jun; Li, Pengfei; Hu, Wei; Wang, Gang; Xu, Zhengkai; Song, Rentao

    2010-12-01

    Transposon tagging is an important tool for gene isolation and functional studies. In maize, several transposon-tagging systems have been developed, mostly using Activator/Dissociation (Ac/Ds) and Mutator systems. Here, we establish another Ac-based transposon system with the donor Ac tightly linked with sugary1 (su1) on maize chromosome 4S. Newly transposed Ac (tr-Acs) were detected based on a negative dosage effect, and long-distance-transposed Ac events were identified and isolated from the donor Ac by a simple backcross scheme. In this study, we identified 208 independent long-distance-transposed Ac lines. Thirty-one flanking sequences of these tr-Acs were isolated and localized in the maize genome. As found in previous studies, the tr-Acs preferentially inserted into genic sequences. The distribution of tr-Acs is not random. In our study, the tr-Acs preferentially transposed into chromosomes 1, 2, 9 and 10. We discuss the preferential distribution of tr-Acs from Ac systems. Our system is complementary to two other Ac-based regional-mutagenesis systems in maize, and the combined use of these systems will achieve an even and high-density distribution of Ac elements throughout the maize genome for functional-genomics studies.

  7. Chemistry of atmospheres.

    NASA Astrophysics Data System (ADS)

    Wayne, R. P.

    Atmospheric chemistry has been the focus of much research activity in recent years. Like its predecessor, this new edition lays down the principles of atmospheric chemistry and provides the necessary background for more detailed study. New developments are covered, including the startling discovery of the "Antarctic ozone hole", and the increasingly rapid changes in the composition of the Earth's atmosphere, apparently a result of man's activities. Information gathered by the Voyager 2 and other space missions, which have provided a new understanding of the atmospheres of planets other than our own, is also discussed.

  8. Carbon Monoxide Affecting Planetary Atmospheric Chemistry

    NASA Astrophysics Data System (ADS)

    He, Chao; Horst, Sarah

    2016-10-01

    Atmospheric hazes are present in a range of solar system and extrasolar planetary atmospheres, and organic hazes, such as that in Titan's atmosphere, could be a source of prebiotic molecules.1 However, the chemistry occurring in planetary atmospheres and the resulting chemical structures are still not clear. Numerous experimental simulations2 have been carried out in the laboratory to understand the chemistry in N2/CH4 atmospheres, but very few simulations4 have included CO in their initial gas mixtures, which is an important component in many N2/CH4 atmospheres including Titan, Triton, and Pluto.3 Here we have conducted a series of atmosphere simulation experiments using AC glow discharge (cold plasma) as energy source to irradiate reactions in gas mixtures of CO, CH4, and N2 with a range of CO mixing ratios (from 0, 0.05%, 0.2%, 0.5%, 1%, 2.5%, to 5%) at low temperature (~100 K). Gas phase products are monitored during the reaction by quadrupole mass spectrometer (MS), and solid phase products are analyzed by solution-state nuclear magnetic resonance spectroscopy (NMR). MS results show that with the increase of CO in the initial gases, the production of nitrogenous organic molecules increases while the production of hydrogen molecules decreases in the gas phase. NMR measurements of the solid phase products show that with the increase of CO, hydrogen atoms bonded to nitrogen or oxygen in unsaturated structures increase while those bonded to saturated carbon decrease, which means more unsaturated species and less saturated species formed with the addition of CO. MS and NMR results demonstrate that the inclusion of CO affects the compositions of both gas and solid phase products, indicating that CO has an important impact on the chemistry occurring in our experiments and probably in planetary atmospheres.1. Hörst, S. M., et al. 2012, AsBio, 12, 8092. Cable, M. L., et al. 2012, Chem. Rev., 112, 18823. Lutz, B. L., et al. 1983, Sci, 220, 1374; Greaves, J. S., et al

  9. AC-electric field dependent electroformation of giant lipid vesicles.

    PubMed

    Politano, Timothy J; Froude, Victoria E; Jing, Benxin; Zhu, Yingxi

    2010-08-01

    Giant vesicles of larger than 5 microm, which have been of intense interest for their potential as drug delivery vehicles and as a model system for cell membranes, can be rapidly formed from a spin-coated lipid thin film under an electric field. In this work, we explore the AC-field dependent electroformation of giant lipid vesicles in aqueous media over a wide range of AC-frequency from 1 Hz to 1 MHz and peak-to-peak field strength from 0.212 V/mm to 40 V/mm between two parallel conducting electrode surfaces. By using fluorescence microscopy, we perform in-situ microscopic observations of the structural evolution of giant vesicles formed from spin-coated lipid films under varied uniform AC-electric fields. The real-time observation of bilayer bulging from the lipid film, vesicle growth and fusing further examine the critical role of AC-induced electroosmotic flow of surrounding fluids for giant vesicle formation. A rich AC-frequency and field strength phase diagram is obtained experimentally to predict the AC-electroformation of giant unilamellar vesicles (GUVs) of l-alpha-phosphatidylcholine, where a weak dependence of vesicle size on AC-frequency is observed at low AC-field voltages, showing decreased vesicle size with a narrowed size distribution with increased AC-frequency. Formation of vesicles was shown to be constrained by an upper field strength of 10 V/mm and an upper AC-frequency of 10 kHz. Within these parameters, giant lipid vesicles were formed predominantly unilamellar and prevalent across the entire electrode surfaces.

  10. The A to Z of A/C plasmids.

    PubMed

    Harmer, Christopher J; Hall, Ruth M

    2015-07-01

    Plasmids belonging to incompatibility groups A and C (now A/C) were among the earliest to be associated with antibiotic resistance in Gram-negative bacteria. A/C plasmids are large, conjugative plasmids with a broad host range. The prevalence of A/C plasmids in collections of clinical isolates has revealed their importance in the dissemination of extended-spectrum β-lactamases and carbapenemases. They also mobilize SGI1-type resistance islands. Revived interest in the family has yielded many complete A/C plasmid sequences, revealing that RA1, designated A/C1, is different from the remainder, designated A/C2. There are two distinct A/C2 lineages. Backbones of 128-130 kb include over 120 genes or ORFs encoding proteins of at least 100 amino acids, but very few have been characterized. Genes potentially required for replication, stability and transfer have been identified, but only the replication system of RA1 and the regulation of transfer have been studied. There is enormous variety in the antibiotic resistance genes carried by A/C2 plasmids but they are usually clustered in larger regions at various locations in the backbone. The ARI-A and ARI-B resistance islands are always at a specific location but have variable content. ARI-A is only found in type 1 A/C2 plasmids, which disseminate blaCMY-2 and blaNDM-1 genes, whereas ARI-B, carrying the sul2 gene, is found in both type 1 and type 2. This review summarizes current knowledge of A/C plasmids, and highlights areas of research to be considered in the future.

  11. Ac-Induced Instability at the Xanthophyllic Locus of Tomato

    PubMed Central

    Peterson, P. W.; Yoder, J. I.

    1993-01-01

    To detect genomic instability caused by Ac elements in transgenic tomatoes, we used the incompletely dominant mutation Xanthophyllic-1 (Xa-1) as a whole plant marker gene. Xa-1 is located on chromosome 10 and in the heterozygote state causes leaves to be yellow. Transgenic Ac-containing tomato plants which differed in the location and number of their Ac elements were crossed to Xa-1 tester lines and F(1) progeny were scored for aberrant somatic sectoring. Of 800 test and control F(1) progeny screened, only four plants had aberrantly high levels of somatic sectors. Three of the plants had twin sectors consisting of green tissue adjacent to white tissue, and the other had twin sectors comprised of green tissue adjacent to tissue more yellow than the heterozygote background. Sectoring was inherited and the two sectoring phenotypes mapped to opposite homologs of chromosome 10; the green/yellow sectoring phenotype mapped in coupling to Xa-1 while the green/white sectoring phenotype mapped in repulsion. The two sectoring phenotypes cosegregated with different single, non-rearranged Acs, and loss of these Acs from the genome corresponded to the loss of sectoring. Sectoring was still observed after transposition of the Ac to a new site which indicated that sectoring was not limited to a single locus. In both sectored lines, meiotic recombination of the sectoring Ac to the opposite homolog caused the phenotype to switch between the green/yellow and the green/white phenotypes. Thus the two different sectoring phenotypes arose from the same Ac-induced mechanism; the phenotype depended on which chromosome 10 homolog the Ac was on. We believe that the twin sectors resulted from chromosome breakage mediated by a single intact, transposition-competent Ac element. PMID:8394266

  12. The Lowest Atmosphere: Atmospheric Boundary Layer Including Atmospheric Surface Layer.

    DTIC Science & Technology

    1996-04-01

    troposphere" as a result of frictional forces. A good definition of the atmospheric boundary layer (ABL) (provided to me by the late Dr. Rudy...wind extends light flag. Raises dust and loose paper; small branches are moved. Small trees in leaf begin to sway; crested wavelets form on inland...Calm. Sea like a mirror. Light air Ripples like scales, no foam crest. Light breeze Small wavelets ; crests have glassy appearance, do not break

  13. A New Method for Detecting and Monitoring Atmospheric Natural Hazards with GPS RO

    NASA Astrophysics Data System (ADS)

    Biondi, R.; Steiner, A. K.; Rieckh, T. M.; Kirchengast, G.

    2014-12-01

    Global Positioning System (GPS) Radio Occultation (RO) allows measurements in any meteorological condition, with global coverage, high vertical resolution, and high accuracy. With more than 13 years of data availability, RO also became a fundamental tool for studying climate change. We present here the application of RO for detecting and monitoring tropical cyclones (TCs), deep convective systems (CSs) and volcanic ash clouds (ACs).Deep CSs and TCs play a fundamental role in atmospheric circulation producing vertical transport, redistributing water vapor and trace gases, changing the thermal structure of the Upper Troposphere and Lower Stratosphere (UTLS) and affecting climate through overshooting into the stratosphere. Explosive volcanic eruptions produce large ACs dangerous for the aviation and they can impact climate when the ash is injected into the UTLS.The detection of cloud top height, the determination of cloud extent, the discrimination of ACs from CSs clouds and the detection of overshooting are main challenges for atmospheric natural hazards study. We created a reference atmosphere with a resolution of 5° in latitude and longitude, sampled on a 1° x 1° grid, and a vertical sampling of 100 m. We then compared RO profiles acquired during TCs, CSs and ACs to the reference atmosphere and computed anomaly profiles.CSs, TCs and the ACs leave a clear signature in the atmosphere which can be detected by RO. Using RO temperature and bending angle profiles we gain insight into the vertical thermal structure and developed a new method for detecting the cloud top altitude with high accuracy.We have characterized the TCs by ocean basins and intensities, showing that they have a different thermal structure and reach to different altitudes according to the basin. We provide statistics on overshooting frequency, achieving results consistent with patterns found in the literature and demonstrating that RO is well suited for this kind of study. We have analyzed the

  14. International Space Station Environmental Control and Life Support System Acceptance Testing for Node 1 Temperature and Humidity Control Subsystem

    NASA Technical Reports Server (NTRS)

    Williams, David E.

    2011-01-01

    The International Space Station (ISS) Node 1 Environmental Control and Life Support (ECLS) System is comprised of five subsystems: Atmosphere Control and Storage (ACS), Atmosphere Revitalization (AR), Fire Detection and Suppression (FDS), Temperature and Humidity Control (THC), and Water Recovery and Management (WRM). This paper will provide a summary of the Node 1 ECLS THC subsystem design and a detailed discussion of the ISS ECLS Acceptance Testing methodology utilized for this subsystem.The International Space Station (ISS) Node 1 Environmental Control and Life Support (ECLS) System is comprised of five subsystems: Atmosphere Control and Storage (ACS), Atmosphere Revitalization (AR), Fire Detection and Suppression (FDS), Temperature and Humidity Control (THC), and Water Recovery and Management (WRM). This paper will provide a summary of the Node 1 ECLS THC subsystem design and a detailed discussion of the ISS ECLS Acceptance Testing methodology utilized for this subsystem.

  15. Clouds in Planetary Atmospheres

    NASA Technical Reports Server (NTRS)

    West, R.

    1999-01-01

    In the terrestrial atmosphere clouds are familiar as vast collections of small water drops or ice cyrstals suspended in the air. The study of clouds touches on many facets of armospheric science. The chemistry of clouds is tied to the chemistry of the surrounding atmosphere.

  16. MODIS Atmospheric Data Handler

    NASA Technical Reports Server (NTRS)

    Anantharaj, Valentine; Fitzpatrick, Patrick

    2008-01-01

    The Moderate Resolution Imaging Spectroradiometer (MODIS) Atmosphere Data Handler software converts the HDF data to ASCII format, and outputs: (1) atmospheric profiles of temperature and dew point and (2) total precipitable water. Quality-control data are also considered in the export procedure.

  17. Clouds in Planetary Atmospheres

    NASA Astrophysics Data System (ADS)

    West, R.; Murdin, P.

    2000-11-01

    What are clouds? The answer to that question is both obvious and subtle. In the terrestrial atmosphere clouds are familiar as vast collections of small water drops or ice crystals suspended in the air. In the atmospheres of Venus, Mars, Jupiter, Saturn, Saturn's moon Titan, Uranus, Neptune, and possibly Pluto, they are composed of several other substances including sulfuric acid, ammonia, hydroge...

  18. Factors and sources influencing ionic composition of atmospheric condensate during winter season in lower troposphere over Delhi, India.

    PubMed

    Kumar, Pawan; Yadav, Sudesh

    2013-03-01

    Atmospheric condensate (AC) and rainwater samples were collected during 2010-2011 winter season from Delhi and characterized for major cations and anions. The observed order of abundance of cations and anions in AC samples was NH (4) (+)  > Ca(2+) > Na(+) > K(+) > Mg(2+) and HCO (3) (-)  > SO (4) (2-)  > Cl(-) > NO (2) (-)  > NO (3) (-)  > F(-), respectively. All samples were alkaline in nature and Σ (cation)/Σ (anion) ratio was found to be close to one. NH (4) (+) emissions followed by Ca(2+) and Mg(2+) were largely responsible for neutralization of acidity caused by high NO( x ) and SO(2) emissions from vehicles and thermal power plants in the region. Interestingly, AC samples show low nitrate content compared with its precursor nitrite, which is commonly reversed in case of rainwater. It could be due to (1) slow light-mediated oxidation of HONO; (2) larger emission of NO(2) and temperature inversion conditions entrapping them; and (3) formation and dissociation of ammonium nitrite, which seems to be possible as both carry close correlation in our data set. Principal component analysis indicated three factors (marine mixed with biomass burning, anthropogenic and terrestrial, and carbonates) for all ionic species. Significantly higher sulfate/nitrate ratio indicates greater anthropogenic contributions in AC samples compared with rainwater. Compared with rainwater, AC samples show higher abundance of all ionic species except SO(4), NO(3), and Ca suggesting inclusion of these ions by wash out process during rain events. Ionic composition and related variations in AC and rainwater samples indicate that two represent different processes in time and space coordinates. AC represents the near-surface interaction whereas rainwater chemistry is indicative of regional patterns. AC could be a suitable way to understand atmospheric water interactions with gas and solid particle species in the lower atmosphere.

  19. Atmospheric Fluorescence Yield

    NASA Technical Reports Server (NTRS)

    Adams, James H., Jr.; Christl, M. J.; Fountain, W. F.; Gregory, J. C.; Martens, K.; Sokolsky, P.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    Several existing and planned experiments estimate the energies of ultra-high energy cosmic rays from air showers using the atmospheric fluorescence from these showers. Accurate knowledge of the conversion from atmospheric fluorescence to energy loss by ionizing particles in the atmosphere is key to this technique. In this paper we discuss a small balloon-borne instrument to make the first in situ measurements versus altitude of the atmospheric fluorescence yield. The instrument can also be used in the lab to investigate the dependence of the fluorescence yield in air on temperature, pressure and the concentrations of other gases that present in the atmosphere. The results can be used to explore environmental effects on and improve the accuracy of cosmic ray energy measurements for existing ground-based experiments and future space-based experiments.

  20. Geochemical cycles of atmospheric gases

    NASA Technical Reports Server (NTRS)

    Walker, J. C. G.; Drever, J. I.

    1988-01-01

    The processes that control the atmosphere and atmospheric changes are reviewed. The geochemical cycles of water vapor, nitrogen, carbon dioxide, oxygen, and minor atmospheric constituents are examined. Changes in atmospheric chemistry with time are discussed using evidence from the rock record and analysis of the present atmosphere. The role of biological evolution in the history of the atmosphere and projected changes in the future atmosphere are considered.

  1. Phylogenetic ecology of the freshwater Actinobacteria acI lineage.

    PubMed

    Newton, Ryan J; Jones, Stuart E; Helmus, Matthew R; McMahon, Katherine D

    2007-11-01

    The acI lineage of freshwater Actinobacteria is a cosmopolitan and often numerically dominant member of lake bacterial communities. We conducted a survey of acI 16S rRNA genes and 16S-23S rRNA internal transcribed spacer regions from 18 Wisconsin lakes and used standard nonphylogenetic and phylogenetic statistical approaches to investigate the factors that determine acI community composition at the local scale (within lakes) and at the regional scale (across lakes). Phylogenetic reconstruction of 434 acI 16S rRNA genes revealed a well-defined and highly resolved phylogeny. Eleven previously unrecognized monophyletic clades, each with > or =97.9% within-clade 16S rRNA gene sequence identity, were identified. Clade community similarity positively correlated with lake environmental similarity but not with geographic distance, implying that the lakes represent a single biotic region containing environmental filters for communities that have similar compositions. Phylogenetically disparate clades within the acI lineage were most abundant at the regional scale, and local communities were comprised of more closely related clades. Lake pH was a strong predictor of the community composition, but only when lakes with a pH below 6 were included in the data set. In the remaining lakes (pH above 6) biogeographic patterns in the landscape were instead a predictor of the observed acI community structure. The nonrandom distribution of the newly defined acI clades suggests potential ecophysiological differences between the clades, with acI clades AI, BII, and BIII preferring acidic lakes and acI clades AII, AVI, and BI preferring more alkaline lakes.

  2. Trapping polar molecules in an ac trap

    SciTech Connect

    Bethlem, Hendrick L.; Veldhoven, Jacqueline van; Schnell, Melanie; Meijer, Gerard

    2006-12-15

    Polar molecules in high-field seeking states cannot be trapped in static traps as Maxwell's equations do not allow a maximum of the electric field in free space. It is possible to generate an electric field that has a saddle point by superposing an inhomogeneous electric field to an homogeneous electric field. In such a field, molecules are focused along one direction, while being defocused along the other. By reversing the direction of the inhomogeneous electric field the focusing and defocusing directions are reversed. When the fields are being switched back and forth at the appropriate rate, this leads to a net focusing force in all directions. We describe possible electrode geometries for creating the desired fields and discuss their merits. Trapping of {sup 15}ND{sub 3} ammonia molecules in a cylindrically symmetric ac trap is demonstrated. We present measurements of the spatial distribution of the trapped cloud as a function of the settings of the trap and compare these to both a simple model assuming a linear force and to full three-dimensional simulations of the experiment. With the optimal settings, molecules within a phase-space volume of 270 mm{sup 3} (m/s){sup 3} remain trapped. This corresponds to a trap depth of about 5 mK and a trap volume of about 20 mm{sup 3}.

  3. Installation considerations for IGBT AC drives

    SciTech Connect

    Skibinski, G.L.

    1997-06-01

    In the last four years, Adjustable Speed ac Drive (ASD) manufacturers have migrated from Bipolar Junction Transistor (BJT) semiconductors to Insulated Gate Bipolar Transistors (IGBTs) as the preferred Output switching device. The advantage of IGBTs over BJTs is that device rise and fall time switching capability is 5 - 10 times faster, resulting in lower device switching loss and a more efficient drive. However, for a similar motor cable length as the BJT drive, the faster output voltage risetime of the IGBT drive may increase the dielectric voltage stress on the motor and cable due to a phenomenon called reflected wave. Faster output dv/dt transitions of IGBT drives also increase the possibility for phenomenon such as increased Common Mode (CM) electrical noise, Electromagnetic Interference (EMI) problems and increased capacitive cable charging current problems. Also, recent experience suggests any Pulse Width Modulated (PWM) drive with a steep fronted output voltage wave form may increase motor shaft voltage and lead to a bearing current phenomenon known as fluting. This paper provides a basic understanding of these issues, as well as solutions, to insure a successful drive system installation.

  4. Atmospheric composition change: Ecosystems-Atmosphere interactions

    NASA Astrophysics Data System (ADS)

    Fowler, D.; Pilegaard, K.; Sutton, M. A.; Ambus, P.; Raivonen, M.; Duyzer, J.; Simpson, D.; Fagerli, H.; Fuzzi, S.; Schjoerring, J. K.; Granier, C.; Neftel, A.; Isaksen, I. S. A.; Laj, P.; Maione, M.; Monks, P. S.; Burkhardt, J.; Daemmgen, U.; Neirynck, J.; Personne, E.; Wichink-Kruit, R.; Butterbach-Bahl, K.; Flechard, C.; Tuovinen, J. P.; Coyle, M.; Gerosa, G.; Loubet, B.; Altimir, N.; Gruenhage, L.; Ammann, C.; Cieslik, S.; Paoletti, E.; Mikkelsen, T. N.; Ro-Poulsen, H.; Cellier, P.; Cape, J. N.; Horváth, L.; Loreto, F.; Niinemets, Ü.; Palmer, P. I.; Rinne, J.; Misztal, P.; Nemitz, E.; Nilsson, D.; Pryor, S.; Gallagher, M. W.; Vesala, T.; Skiba, U.; Brüggemann, N.; Zechmeister-Boltenstern, S.; Williams, J.; O'Dowd, C.; Facchini, M. C.; de Leeuw, G.; Flossman, A.; Chaumerliac, N.; Erisman, J. W.

    Ecosystems and the atmosphere: This review describes the state of understanding the processes involved in the exchange of trace gases and aerosols between the earth's surface and the atmosphere. The gases covered include NO, NO 2, HONO, HNO 3, NH 3, SO 2, DMS, Biogenic VOC, O 3, CH 4, N 2O and particles in the size range 1 nm-10 μm including organic and inorganic chemical species. The main focus of the review is on the exchange between terrestrial ecosystems, both managed and natural and the atmosphere, although some new developments in ocean-atmosphere exchange are included. The material presented is biased towards the last decade, but includes earlier work, where more recent developments are limited or absent. New methodologies and instrumentation have enabled, if not driven technical advances in measurement. These developments have advanced the process understanding and upscaling of fluxes, especially for particles, VOC and NH 3. Examples of these applications include mass spectrometric methods, such as Aerosol Mass Spectrometry (AMS) adapted for field measurement of atmosphere-surface fluxes using micrometeorological methods for chemically resolved aerosols. Also briefly described are some advances in theory and techniques in micrometeorology. For some of the compounds there have been paradigm shifts in approach and application of both techniques and assessment. These include flux measurements over marine surfaces and urban areas using micrometeorological methods and the up-scaling of flux measurements using aircraft and satellite remote sensing. The application of a flux-based approach in assessment of O 3 effects on vegetation at regional scales is an important policy linked development secured through improved quantification of fluxes. The coupling of monitoring, modelling and intensive flux measurement at a continental scale within the NitroEurope network represents a quantum development in the application of research teams to address the underpinning

  5. Dielectrophoretic particle-particle interaction under AC electrohydrodynamic flow conditions.

    PubMed

    Lee, Doh-Hyoung; Yu, Chengjie; Papazoglou, Elisabeth; Farouk, Bakhtier; Noh, Hongseok M

    2011-09-01

    We used the Maxwell stress tensor method to understand dielectrophoretic particle-particle interactions and applied the results to the interpretation of particle behaviors under alternating current (AC) electrohydrodynamic conditions such as AC electroosmosis (ACEO) and electrothermal flow (ETF). Distinct particle behaviors were observed under ACEO and ETF. Diverse particle-particle interactions observed in experiments such as particle clustering, particles keeping a certain distance from each other, chain and disc formation and their rotation, are explained based on the numerical simulation data. The improved understanding of particle behaviors in AC electrohydrodynamic flows presented here will enable researchers to design better particle manipulation strategies for lab-on-a-chip applications.

  6. Optimal design of AC filter circuits in HVDC converter stations

    SciTech Connect

    Saied, M.M.; Khader, S.A.

    1995-12-31

    This paper investigates the reactive power as well as the harmonic conditions on both the valve and the AC-network sides of a HVDC converter station. The effect of the AC filter circuits is accurately modeled. The program is then augmented by adding an optimization routine. It can identify the optimal filter configuration, yielding the minimum current distortion factor at the AC network terminals for a prespecified fundamental reactive power to be provided by the filter. Several parameter studies were also conducted to illustrate the effect of accidental or intentional deletion of one of the filter branches.

  7. ACS (Alma Common Software) operating a set of robotic telescopes

    NASA Astrophysics Data System (ADS)

    Westhues, C.; Ramolla, M.; Lemke, R.; Haas, M.; Drass, H.; Chini, R.

    2014-07-01

    We use the ALMA Common Software (ACS) to establish a unified middleware for robotic observations with the 40cm Optical, 80cm Infrared and 1.5m Hexapod telescopes located at OCA (Observatorio Cerro Armazones) and the ESO 1-m located at La Silla. ACS permits to hide from the observer the technical specifications, like mount-type or camera-model. Furthermore ACS provides a uniform interface to the different telescopes, allowing us to run the same planning program for each telescope. Observations are carried out for long-term monitoring campaigns to study the variability of stars and AGN. We present here the specific implementation to the different telescopes.

  8. Cyclotron production of Ac-225 for targeted alpha therapy.

    PubMed

    Apostolidis, C; Molinet, R; McGinley, J; Abbas, K; Möllenbeck, J; Morgenstern, A

    2005-03-01

    The feasibility of producing Ac-225 by proton irradiation of Ra-226 in a cyclotron through the reaction Ra-226(p,2n)Ac-225 has been experimentally demonstrated for the first time. Proton energies were varied from 8.8 to 24.8 MeV and cross-sections were determined by radiochemical analysis of reaction yields. Maximum yields were reached at incident proton energies of 16.8 MeV. Radiochemical separation of Ac-225 from the irradiated target yielded a product suitable for targeted alpha therapy of cancer.

  9. Environmental Control and Life Support System

    NASA Technical Reports Server (NTRS)

    Ray, Charles; Adams, Alan

    1990-01-01

    Viewgraphs on the Environmental Control and Life Support System (ECLSS) for the space station are presented. The ECLSS is divided into six subsystems: temperature and humidity control (THC), atmosphere control and supply (ACS), atmosphere revitalization (AR), fire detection and suppression (FDS), water recovery management (WRM), and waste management (WM). Topics covered include: ECLSS subsystem functions; ECLSS distributed system; ECLSS functional distribution; CO2 removal; CO2 reduction; oxygen generation; urine processor; and potable water recovery.

  10. Integrated Atmosphere Resource Recovery and Environmental Monitoring Technology Demonstration for Deep Space Exploration

    NASA Technical Reports Server (NTRS)

    Perry, Jay L.; Abney, Morgan B.; Knox, James C.; Parrish, Keith J.; Roman, Monserrate C.; Jan, Darrell L.

    2012-01-01

    Exploring the frontiers of deep space continues to be defined by the technological challenges presented by safely transporting a crew to and from destinations of scientific interest. Living and working on that frontier requires highly reliable and efficient life support systems that employ robust, proven process technologies. The International Space Station (ISS), including its environmental control and life support (ECLS) system, is the platform from which humanity's deep space exploration missions begin. The ISS ECLS system Atmosphere Revitalization (AR) subsystem and environmental monitoring (EM) technical architecture aboard the ISS is evaluated as the starting basis for a developmental effort being conducted by the National Aeronautics and Space Administration (NASA) via the Advanced Exploration Systems (AES) Atmosphere Resource Recovery and Environmental Monitoring (ARREM) Project.. An evolutionary approach is employed by the ARREM project to address the strengths and weaknesses of the ISS AR subsystem and EM equipment, core technologies, and operational approaches to reduce developmental risk, improve functional reliability, and lower lifecycle costs of an ISS-derived subsystem architecture suitable for use for crewed deep space exploration missions. The most promising technical approaches to an ISS-derived subsystem design architecture that incorporates promising core process technology upgrades will be matured through a series of integrated tests and architectural trade studies encompassing expected exploration mission requirements and constraints.

  11. Transboundary atmospheric lead pollution.

    PubMed

    Erel, Yigal; Axelrod, Tamar; Veron, Alain; Mahrer, Yitzak; Katsafados, Petros; Dayan, Uri

    2002-08-01

    A high-temporal resolution collection technique was applied to refine aerosol sampling in Jerusalem, Israel. Using stable lead isotopes, lead concentrations, synoptic data, and atmospheric modeling, we demonstrate that lead detected in the atmosphere of Jerusalem is not only anthropogenic lead of local origin but also lead emitted in other countries. Fifty-seven percent of the collected samples contained a nontrivial fraction of foreign atmospheric lead and had 206Pb/207Pb values which deviated from the local petrol-lead value (206Pb/207Pb = 1.113) by more than two standard deviations (0.016). Foreign 206Pb/207Pb values were recorded in Jerusalem on several occasions. The synoptic conditions on these dates and reported values of the isotopic composition of lead emitted in various countries around Israel suggest that the foreign lead was transported to Jerusalem from Egypt, Turkey, and East Europe. The average concentration of foreign atmospheric lead in Jerusalem was 23 +/- 17 ng/m3, similar to the average concentration of local atmospheric lead, 21 +/- 18 ng/ m3. Hence, the load of foreign atmospheric lead is similar to the load of local atmospheric lead in Jerusalem.

  12. Reference Atmosphere for Mercury

    NASA Technical Reports Server (NTRS)

    Killen, Rosemary M.

    2002-01-01

    We propose that Ar-40 measured in the lunar atmosphere and that in Mercury's atmosphere is due to current diffusion into connected pore space within the crust. Higher temperatures at Mercury, along with more rapid loss from the atmosphere will lead to a smaller column abundance of argon at Mercury than at the Moon, given the same crustal abundance of potassium. Because the noble gas abundance in the Hermean atmosphere represents current effusion, it is a direct measure of the crustal potassium abundance. Ar-40 in the atmospheres of the planets is a measure of potassium abundance in the interiors, since Ar-40 is a product of radiogenic decay of K-40 by electron capture with the subsequent emission of a 1.46 eV gamma-ray. Although the Ar-40 in the Earth's atmosphere is expected to have accumulated since the late bombardment, Ar-40 in the atmospheres of Mercury and the Moon is eroded quickly by photoionization and electron impact ionization. Thus, the argon content in the exospheres of the Moon and Mercury is representative of current effusion rather than accumulation over the lifetime of the planet.

  13. Glacial atmospheric phosphorus deposition

    NASA Astrophysics Data System (ADS)

    Kjær, Helle Astrid; Dallmayr, Remi; Gabrieli, Jacopo; Goto-Azuma, Kumiko; Hirabayashi, Motohiro; Svensson, Anders; Vallelonga, Paul

    2016-04-01

    Phosphorus in the atmosphere is poorly studied and thus not much is known about atmospheric phosphorus and phosphate transport and deposition changes over time, though it is well known that phosphorus can be a source of long-range nutrient transport, e.g. Saharan dust transported to the tropical forests of Brazil. In glacial times it has been speculated that transport of phosphorus from exposed shelves would increase the ocean productivity by wash out. However whether the exposed shelf would also increase the atmospheric load to more remote places has not been investigated. Polar ice cores offer a unique opportunity to study the atmospheric transport of aerosols on various timescales, from glacial-interglacial periods to recent anthropogenic influences. We have for the first time determined the atmospheric transport of phosphorus to the Arctic by means of ice core analysis. Both total and dissolved reactive phosphorus were measured to investigate current and past atmospheric transport of phosphorus to the Arctic. Results show that glacial cold stadials had increased atmospheric total phosphorus mass loads of 70 times higher than in the past century, while DRP was only increased by a factor of 14. In the recent period we find evidence of a phosphorus increase over the past 50 yrs in ice cores close to human occupation likely correlated to forest fires. References: Kjær, Helle Astrid, et al. "Continuous flow analysis method for determination of dissolved reactive phosphorus in ice cores." Environmental science & technology 47.21 (2013): 12325-12332. Kjær, Helle Astrid, et al. "Greenland ice cores constrain glacial atmospheric fluxes of phosphorus." Journal of Geophysical Research: Atmospheres120.20 (2015).

  14. Differential Roles of AC2 and AC4 of Cassava Geminiviruses in Mediating Synergism and Suppression of Posttranscriptional Gene Silencing

    PubMed Central

    Vanitharani, Ramachandran; Chellappan, Padmanabhan; Pita, Justin S.; Fauquet, Claude M.

    2004-01-01

    Posttranscriptional gene silencing (PTGS) in plants is a natural defense mechanism against virus infection. In mixed infections, virus synergism is proposed to result from suppression of the host defense mechanism by the viruses. Synergistic severe mosaic disease caused by simultaneous infection with isolates of the Cameroon strain of African cassava mosaic virus (ACMV-[CM]) and East African cassava mosaic Cameroon virus (EACMCV) in cassava and tobacco is characterized by a dramatic increase in symptom severity and a severalfold increase in viral-DNA accumulation by both viruses compared to that in singly infected plants. Here, we report that synergism between ACMV-[CM] and EACMCV is a two-way process, as the presence of the DNA-A component of ACMV-[CM] or EACMCV in trans enhanced the accumulation of viral DNA of EACMCV and ACMV-[CM], respectively, in tobacco BY-2 protoplasts. Furthermore, transient expression of ACMV-[CM] AC4 driven by the Cauliflower mosaic virus 35S promoter (p35S-AC4) enhanced EACMCV DNA accumulation by ∼8-fold in protoplasts, while p35S-AC2 of EACMCV enhanced ACMV-[CM] DNA accumulation, also by ∼8-fold. An Agrobacterium-based leaf infiltration assay determined that ACMV-[CM] AC4 and EACMCV AC2, the putative synergistic genes, were able to suppress PTGS induced by green fluorescent protein (GFP) and eliminated the short interfering RNAs associated with PTGS, with a correlated increase in GFP mRNA accumulation. In addition, we have identified AC4 of Sri Lankan cassava mosaic virus and AC2 of Indian cassava mosaic virus as suppressors of PTGS, indicating that geminiviruses evolved differently in regard to interaction with the host. The specific and different roles played by these AC2 and AC4 proteins of cassava geminiviruses in regulating anti-PTGS activity and their relation to synergism are discussed. PMID:15308741

  15. Triton's Distorted Atmosphere

    NASA Technical Reports Server (NTRS)

    Elliot, J. L.; Stansberry, J. A.; Olkin, C. B.; Agner, M. A.; Davies, M. E.

    1998-01-01

    A stellar-occultation light curve for Triton shows asymmetry that can be understood if Triton's middle atmosphere is distorted from spherical symmetry. Although a globally oblate model can explain the data, the inferred atmospheric flattening is so large that it could be caused only by an unrealistic internal mass distribution or highly supersonic zonal winds. Cyclostrophic winds confined to a jet near Triton's northern or southern limbs (or both) could also be responsible for the details of the light curve, but such winds are required to be slightly supersonic. Hazes and clouds in the atmosphere are unlikely to have caused the asymmetry in the light curve.

  16. Atmospheric refraction: a history

    NASA Astrophysics Data System (ADS)

    Lehn, Waldemar H.; van der Werf, Siebren

    2005-09-01

    We trace the history of atmospheric refraction from the ancient Greeks up to the time of Kepler. The concept that the atmosphere could refract light entered Western science in the second century B.C. Ptolemy, 300 years later, produced the first clearly defined atmospheric model, containing air of uniform density up to a sharp upper transition to the ether, at which the refraction occurred. Alhazen and Witelo transmitted his knowledge to medieval Europe. The first accurate measurements were made by Tycho Brahe in the 16th century. Finally, Kepler, who was aware of unusually strong refractions, used the Ptolemaic model to explain the first documented and recognized mirage (the Novaya Zemlya effect).

  17. Evolution of Atmospheres

    SciTech Connect

    Hanson, B.

    1993-02-12

    An atmosphere is the dynamic gaseous boundary layer between a planet and space. Many complex interactions affect the composition and time evolution of an atmosphere and control the environment - or climate - at a planet's surface. These include both reactions within the atmosphere as well as exchange of energy, gases, and dust with the planet below and the solar system above; for Earth today, interactions with the biosphere and oceans are paramount. In view of the large changes in inputs of energy and gases that have occurred since planets began to form and the complexity of the chemistry, it is not surprising that planetary climates have changed greatly and are continuing to change.

  18. Atmospheric refraction: a history.

    PubMed

    Lehn, Waldemar H; van der Werf, Siebren

    2005-09-20

    We trace the history of atmospheric refraction from the ancient Greeks up to the time of Kepler. The concept that the atmosphere could refract light entered Western science in the second century B.C. Ptolemy, 300 years later, produced the first clearly defined atmospheric model, containing air of uniform density up to a sharp upper transition to the ether, at which the refraction occurred. Alhazen and Witelo transmitted his knowledge to medieval Europe. The first accurate measurements were made by Tycho Brahe in the 16th century. Finally, Kepler, who was aware of unusually strong refractions, used the Ptolemaic model to explain the first documented and recognized mirage (the Novaya Zemlya effect).

  19. Heterogeneous Atmospheric Chemistry

    NASA Astrophysics Data System (ADS)

    Schryer, David R.

    In the past few years it has become increasingly clear that heterogeneous, or multiphase, processes play an important role in the atmosphere. Unfortunately the literature on the subject, although now fairly extensive, is still rather dispersed. Furthermore, much of the expertise regarding heterogeneous processes lies in fields not directly related to atmospheric science. Therefore, it seemed desirable to bring together for an exchange of ideas, information, and methodologies the various atmospheric scientists who are actively studying heterogeneous processes as well as other researchers studying similar processes in the context of other fields.

  20. Absorption and Attenuation Coefficients Using the WET Labs ac-s in the Mid-Atlantic Bight: Field Measurements and Data Analysis

    NASA Technical Reports Server (NTRS)

    Ohi, Nobuaki; Makinen, Carla P.; Mitchell, Richard; Moisan, Tiffany A.

    2008-01-01

    Ocean color algorithms are based on the parameterization of apparent optical properties as a function of inherent optical properties. WET Labs underwater absorption and attenuation meters (ac-9 and ac-s) measure both the spectral beam attenuation [c (lambda)] and absorption coefficient [a (lambda)]. The ac-s reports in a continuous range of 390-750 nm with a band pass of 4 nm, totaling approximately 83 distinct wavelengths, while the ac-9 reports at 9 wavelengths. We performed the ac-s field measurements at nine stations in the Mid-Atlantic Bight from water calibrations to data analysis. Onboard the ship, the ac-s was calibrated daily using Milli Q-water. Corrections for the in situ temperature and salinity effects on optical properties of water were applied. Corrections for incomplete recovery of the scattered light in the ac-s absorption tube were performed. The fine scale of spectral and vertical distributions of c (lambda) and a (lambda) were described from the ac-s. The significant relationships between a (674) and that of spectrophotometric analysis and chlorophyll a concentration of discrete water samples were observed.

  1. AC Josephson effect applications in microwave systems

    NASA Astrophysics Data System (ADS)

    Larkin, Serguey Y.

    1996-12-01

    analysis allow to get the picture of temperature distribution along the plasma cord diameter in accordance with dynamics of thermonuclear process development. Modem raclioastronomic research gives scientists the unique information on the world tructure. It is also necessary to analyze Space microwave radiation providing exclusive sensitivity of the equipment. In both cases equipment is required to be superwide band, to have high sensitivity and ability to operate at more than 300 GHz frequencies. Today all these requirements are met by the devices using the ac Josephson effect. The Josephson junctions are used as an active transforming element in such devices. At the end of 20 century the sphere of their utilization embraces medicine, communications, radiophysics, space exploration, ecology, military use, etc. The State Research Center "Fonon" ( SRC "Fonon") of the State Committee on Science and Technology of Ukraine was founded in 1991. The main aim of its creation was to concentrate the scientific and financial efforts for development and production of unique devices based on the results of fundamental study in physics of high T superconductivity. First of all we were interested in technological research on the obtaining of low impedance Josephson junctions out of the High T thin films. Using such junctions in combination with our original techniques developed in our Center we have succeed in creating the following new generation equipment: industrial set-up of the frequency meter in the range of 60 ... 600 GHz; experimental set-up of the spectrum analyzer operating in the range of 50 250 GHz; experimental model of radiometric receiver in 180...260 GHz range. All the above devices are based on the using ac Josephson effect for the receiving and processing mm- and submm- microwave signals.

  2. An AC electroosmotic micropump for circular chromatographic applications.

    PubMed

    Debesset, S; Hayden, C J; Dalton, C; Eijkel, J C T; Manz, A

    2004-08-01

    Flow rates of up to 50 microm s(-1) have been successfully achieved in a closed-loop channel using an AC electroosmotic pump. The AC electroosmotic pump is made of an interdigitated array of unequal width electrodes located at the bottom of a channel, with an AC voltage applied between the small and the large electrodes. The flow rate was found to increase linearly with the applied voltage and to decrease linearly with the applied frequency. The pump is expected to be suitable for circular chromatography for the following reasons: the driving forces are distributed over the channel length and the pumping direction is set by the direction of the interdigitated electrodes. Pumping in a closed-loop channel can be achieved by arranging the electrode pattern in a circle. In addition the inherent working principle of AC electroosmotic pumping enables the independent optimisation of the channel height or the flow velocity.

  3. A hybrid electromechanical solid state switch for ac power control

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Bidirectional thyristor coupled to a series of actuator driven electromechanical contacts generates hybrid electromechanical solid state switch for ac power control. Device is useful in power control applications where zero crossover switching is required.

  4. Basic concepts of induced AC voltages on pipelines

    SciTech Connect

    Kirkpatrick, E.L.

    1995-07-01

    The phenomena of induced AC on pipelines sharing common rights-of-way with overhead high-voltage electrical transmission power lines is discussed. Basic concepts and techniques for personnel safety and some pipeline protective measures are reviewed.

  5. Evolution of AC conductivity of wet illitic clay during drying

    NASA Astrophysics Data System (ADS)

    Csáki, Š.; Štubňa, I.; Trnovcová, V.; Ondruška, J.; Vozár, L.; Dobroň, P.

    2017-02-01

    The evolution of the AC electrical conductivity during drying as well as the relationship between sample volume and moisture of green illite samples were investigated. The samples were prepared from illitic clay (80 mass % illite, 4 mass % montmorillonite, 12 mass % quartz and 4 mass % of orthoclase) and distilled water with initial moisture content 36 mass % and were freely dried in air. Conductivity was measured by the volt-ampere method with AC power supply of 5 V in the frequency range from 50 Hz to 10 kHz. The AC conductivity steeply increased with increasing moisture, up to 15 mass %. At higher values of the moisture, the AC conductivity was high and almost constant. The volume of samples increased with increasing moisture when the moisture was higher than 8 mass %. Below this value, the dimensions of samples do not significantly change. The dependence of the relative volume change on moisture is presented in a form of the Bigot’s curve.

  6. Dc to ac converter operates efficiently at low input voltages

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Self-oscillating dc to ac converter with transistor switching to produce a square wave output is used for low and high voltage power sources. The converter has a high efficiency throughout a wide range of loads.

  7. Fabrication of alumina films with laminated structures by ac anodization

    PubMed Central

    Segawa, Hiroyo; Okano, Hironaga; Wada, Kenji; Inoue, Satoru

    2014-01-01

    Anodization techniques by alternating current (ac) are introduced in this review. By using ac anodization, laminated alumina films are fabricated. Different types of alumina films consisting of 50–200 nm layers were obtained by varying both the ac power supply and the electrolyte. The total film thickness increased with an increase in the total charge transferred. The thickness of the individual layers increased with the ac voltage; however, the anodization time had little effect on the film thickness. The laminated alumina films resembled the nacre structure of shells, and the different morphologies exhibited by bivalves and spiral shells could be replicated by controlling the rate of increase of the applied potentials. PMID:27877636

  8. Fast electric dipole transitions in Ra-Ac nuclei

    SciTech Connect

    Ahmad, I.

    1985-01-01

    Lifetime of levels in /sup 225/Ra, /sup 225/Ac, and /sup 227/Ac have been measured by delayed coincidence techniques and these have been used to determine the E1 gamma-ray transition probabilities. The reduced E1 transition probabilities. The reduced E1 transition probabilities in /sup 225/Ra and /sup 225/Ac are about two orders of magnitude larger than the values in mid-actinide nuclei. On the other hand, the E1 rate in /sup 227/Ac is similar to those measured in heavier actinides. Previous studies suggest the presence of octupole deformation in all the three nuclei. The present investigation indicates that fast E1 transitions occur for nuclei with octupole deformation. However, the studies also show that there is no one-to-one correspondence between E1 rate and octupole deformation. 13 refs., 4 figs.

  9. ACS Algorithm in Discrete Ordinates for Pressure Vessel Dosimetry

    NASA Astrophysics Data System (ADS)

    Walters, William; Haghighat, Alireza

    2016-02-01

    The Adaptive Collision Source (ACS) method can solve the Linear Boltzmann Equation (LBE) more efficiently by adaptation of the angular quadrature order. This is similar to, and essentially an extension of, the first collision source method. Previously, the ACS methodology has been implemented into the TITAN discrete ordinates code, and has shown speedups of 2-4 on a simple test problem, with very little loss of accuracy (within a provided adaptive tolerance). This work examines the use of the ACS method for a more realistic problem: pressure vessel dosimetry with the VENUS-2 MOX-fuelled reactor dosimetry benchmark. The ACS method proved to be able to obtain accurate results while being approximately twice as efficient as using a constant quadrature in a standard source iteration scheme.

  10. Effect of AC Electrostatic Precipitator on Removal Diesel Exhaust Particles

    NASA Astrophysics Data System (ADS)

    Kawakami, Hitomi; Zukeran, Akinori; Yasumoto, Koji; Kubojima, Masaki; Ehara, Yoshiyasu; Yamamoto, Toshiaki

    Collection of low resistive particulate matter (PM) generated from automobile and marine diesel engines or diesel generators have been known to be difficult by the conventional electrostatic precipitators (ESP). The collection efficiency for two types ESPs such as conventional DC energized ESP (DC ESP) and rectangular-AC-waveform energized ESP (AC ESP) were investigated. The low resistive PMs agglomerate like a pearl-chain on the collection plate in DC ESP, so that these are detached from the collection plate by electrostatic repulsion force and wind force. The pearl-chain particles are changed the shape, which is such a spherical, by AC ESP. Therefore, the particle re-entrainment is suppressed by AC ESP.

  11. ISTTOK upgrade towards AC and remote operation

    NASA Astrophysics Data System (ADS)

    Fernandes, H.; Silva, C.; Carvalho, B.; Sousa, J.; Valcárcel, D.; Neto, A.; Fortunato, J.; Carvalho, I.; Varandas, C. A. F.

    2006-12-01

    ISTTOK has performed one of the earliest experiments of AC tokamak operation showing that long discharges could be produced merely with inductive current drive. However, due to the design of the machine, the data acquisition system and the power supplies, a limit of 250 ms (six times the nominal forward shot duration) is currently imposed. In this paper the relevant constrains to attain current operation up to the limit of the stable toroidal magnetic field (3s) are discussed and the work being carried out to achieve this goal is presented. The conditions that shall be accomplished are: (i) removing the power deposited on the limiters; (ii) density control through gas puffing and monitoring the recycling from the walls; (iii) assessment of the free magnetic flux available on the iron core (Wmax=0.2 Vs); (iv) reformulation of the data acquisition system towards an event driven philosophy maintaining the actual distributed architecture but allowing a real-time control; (v) active control of the equilibrium magnetic fields implementing a digital plasma position estimator and actuator through new power supplies for the poloidal magnetic fields. As a new high level software was needed to implement all this features, the ISTTOK data acquisition system and control has been totally redesigned in JAVA/SQL database technology and time stamps events were adopted to catalogue the data. This software has been design keeping in mind the needs for remote participation and operation of the machine. Therefore, a cooperative environment has been implemented where several persons can be connected together to the platform, programming their own devices and exchanging knowledge or opinions through an embedded chat.

  12. Antifriction coatings based on a-C for biomedicine applications

    NASA Astrophysics Data System (ADS)

    Yurjev, Y. N.; Kiseleva, D. V.; Zaitcev, D. A.; Sidelev, D. V.; Korneva, O. S.

    2016-01-01

    This article reports on the investigation of mechanical properties of carbon films deposited by dual magnetron sputtering system with closed and mirror magnetic field. There is shown that a-C films with predominantly sp2-phase have relatively high hardness (up to 20 GPa) and low friction index (∼0.01). The influence of magnetic field on friction index is determined. The analysis of experimental data shows the obtained a-C samples can be used for biomedicine applications.

  13. An AC magnetohydrodynamic micropump: towards a true integrated microfluidic system

    SciTech Connect

    Lee, A P; Lemoff, A V; McConaghy, C F; Miles, R R

    1999-03-01

    An AC Magnetohydrodynamic (MHD) micropump has been demonstrated in which the Lorentz force is used to propel an electrolytic solution along a microchannel etched in silicon. This micropump has no moving parts, produces a continuous (not pulsatile) flow, and is compatible with solutions containing biological specimens. micropump, using the Lorentz force as the pumping mechanism for biological analysis. The AC Magnetohydrodynamic (MHD) micropump investigated produces a continuous flow and allows for complex microchannel design.

  14. Accelerator Production of 225Ac For Alpha-Immunotherapy

    NASA Astrophysics Data System (ADS)

    Weidner, J. W.; Nortier, F. M.; Bach, H. T.; John, K. D.; Couture, A.; Ullmann, J. L.; Fassbender, M. E.; Goff, G. S.; Taylor, W.; Valdez, F.; Wolfsberg, L. E.; Cisneros, M.; Dry, D.; Gallegos, M.; Gritzo, R.; Bitteker, L. J.; Wender, S.; Baty, R. S.

    2011-06-01

    225Ac has tremendous potential for the treatment of metastatic cancer due to the four alpha-particles emitted during its decay to stable 209Bi. Additionally, it is one of the few alpha-emitters being considered for clinical trials. The anticipated 225Ac demand for these trials is expected to far exceed the annual worldwide supply of approximately 1,000 mCi/yr. Consequently, the DOE Office of Science has funded investigations into accelerator-based production of 225Ac. Existing 232Th(p,x)225Ac cross section data indicate that up to 480 mCi/day of 225Ac could be created by bombarding a thick target of natural thorium with 100 MeV protons at the Los Alamos Isotope Production Facility. To verify these predictions, experiments are underway at the Los Alamos Neutron Science Center to measure the 232Th(p,x)225Ac production cross sections for protons in the energy range 40-200 MeV, and at 800 MeV. For 800 MeV protons, preliminary results indicate that the 225Ac production cross section is 12.4±0.6 mb and the 225Ra production cross section is 3.2±0.2 mb. Moreover, preliminary results suggest that the 227Ac production cross section is 16±1 mb. Experiments to measure these same cross sections at proton energies below 200 MeV are planned for the last half of calendar year 2010.

  15. Diffusive suppression of AC-Stark shifts in atomic magnetometers

    PubMed Central

    Sulai, I. A.; Wyllie, R.; Kauer, M.; Smetana, G. S.; Wakai, R. T.; Walker, T. G.

    2016-01-01

    In atomic magnetometers, the vector AC-Stark shift associated with circularly polarized light generates spatially varying effective magnetic fields, which limit the magnetometer response and serve as sources of noise. We describe a scheme whereby optically pumping a small subvolume of the magnetometer cell and relying on diffusion to transport polarized atoms allows a magnetometer to be operated with minimal sensitivity to the AC-Stark field. © 2013 Optical Society of America PMID:23503278

  16. Development of an AC Module System: Final Technical Report

    SciTech Connect

    Suparna Kadam; Miles Russell

    2012-06-15

    The GreenRay Inc. program focused on simplifying solar electricity and making it affordable and accessible to the mainstream population. This was accomplished by integrating a solar module, micro-inverter, mounting and monitoring into a reliable, 'plug and play' AC system for residential rooftops, offering the following advantages: (1) Reduced Cost: Reduction in installation labor with fewer components, faster mounting, faster wiring. (2) Maximized Energy Production: Each AC Module operates at its maximum, reducing overall losses from shading, mismatch, or module downtime. (3) Increased Safety. Electrical and fire safety experts agree that AC Modules have significant benefits, with no energized wiring or live connections during installation, maintenance or emergency conditions. (4) Simplified PV for a Broader Group of Installers. Dramatic simplification of design and installation of a solar power system, enabling faster and more efficient delivery of the product into the market through well-established, mainstream channels. This makes solar more accessible to the public. (5) Broadened the Rooftop Market: AC Modules enable solar for many homes that have shading, split roofs, or obstructions. In addition, due to the smaller building block size of 200W vs. 1000W, homeowners with budget limitations can start small and add to their systems over time. Through this DOE program GreenRay developed the all-in-one AC Module system with an integrated PV Module and microinverter, custom residential mounting and performance monitoring. Development efforts took the product from its initial concept, through prototypes, to a commercial product sold and deployed in the residential market. This pilot deployment has demonstrated the technical effectiveness of the AC Module system in meeting the needs and solving the problems of the residential market. While more expensive than the traditional central inverter systems at the pilot scale, the economics of AC Modules become more and more

  17. AC-Induced Bias Potential Effect on Corrosion of Steels

    DTIC Science & Technology

    2009-02-05

    AC-Induced Bias Potential Effect on Corrosion of Steels J.E. Jackson, A.N. Lasseigne, D.L. Olson, and B. Mishra Feb. 5, 2009 G2MT Generation 2...UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Generation 2 Materials Technology LLC,10281 Foxfire St,Firestone,CO,80504 8...Pokhodnaya, 1991). AC Self-biasing (from RF) Model 3 Voltage waveforms at generator (Va) and target (Vb) in sinusoidally-excited rf discharge

  18. Search for {beta}-delayed fission of {sup 228}Ac

    SciTech Connect

    Xu Yanbing; Ding Huajie; Yuan Shuanggui; Yang Weifan; Niu Yanning; Li Yingjun; Xiao Yonghou; Zhang Shengdong; Lu Xiting

    2006-10-15

    Radium was radiochemically separated from natural thorium. Thin {sup 228}Ra{yields}{beta}{sup -228}Ac sources were prepared and exposed to mica fission track detectors, and measured by an HPGe {gamma}-ray detector. The {beta}-delayed fission events of {sup 228}Ac were observed and its {beta}-delayed fission probability was found to be (5{+-}2)x10{sup -12}.

  19. Alternating parity structure in doubly odd /sup 218/Ac

    SciTech Connect

    Debray, M.E.; Davidson, M.; Kreiner, A.J.; Davidson, J.; Falcone, G.; Hojman, D.; Santos, D.

    1989-03-01

    States in doubly odd /sup 218/Ac have been studied using in-beam ..cap alpha..-, ..gamma..-, and e/sup -/-spectroscopy techniques mainly through the /sup 209/Bi(/sup 12/C,3n)= fusion-evaporation reaction. /sup 218/Ac shows a band structure, with interleaved states of alternating parities connected by enhanced B(E1) transitions, which is strikingly similar to the one in its isotone /sup 217/Ra.

  20. Accelerator Production of {sup 225}Ac For Alpha-Immunotherapy

    SciTech Connect

    Weidner, J. W.; Nortier, F. M.; Bach, H. T.; John, K. D.; Couture, A.; Ullmann, J. L.; Fassbender, M. E.; Goff, G. S.; Taylor, W.; Valdez, F.; Wolfsberg, L. E.; Cisneros, M.; Dry, D.; Gallegos, M.; Gritzo, R.; Bitteker, L. J.; Wender, S.; Baty, R. S.

    2011-06-01

    {sup 225}Ac has tremendous potential for the treatment of metastatic cancer due to the four alpha-particles emitted during its decay to stable {sup 209}Bi. Additionally, it is one of the few alpha-emitters being considered for clinical trials. The anticipated {sup 225}Ac demand for these trials is expected to far exceed the annual worldwide supply of approximately 1,000 mCi/yr. Consequently, the DOE Office of Science has funded investigations into accelerator-based production of {sup 225}Ac. Existing {sup 232}Th(p,x){sup 225}Ac cross section data indicate that up to 480 mCi/day of {sup 225}Ac could be created by bombarding a thick target of natural thorium with 100 MeV protons at the Los Alamos Isotope Production Facility. To verify these predictions, experiments are underway at the Los Alamos Neutron Science Center to measure the {sup 232}Th(p,x){sup 225}Ac production cross sections for protons in the energy range 40-200 MeV, and at 800 MeV. For 800 MeV protons, preliminary results indicate that the {sup 225}Ac production cross section is 12.4{+-}0.6 mb and the {sup 225}Ra production cross section is 3.2{+-}0.2 mb. Moreover, preliminary results suggest that the {sup 227}Ac production cross section is 16{+-}1 mb. Experiments to measure these same cross sections at proton energies below 200 MeV are planned for the last half of calendar year 2010.

  1. SRNL Atmospheric Technologies Group

    ScienceCinema

    Viner, Brian; Parker, Matthew J.

    2016-07-12

    The Savannah River National Laboratory, Atmospheric Technologies Group, conducts a best-in class Applied Meteorology Program to ensure the Department of Energy’s Savannah River Site is operated safely and complies with stringent environmental regulations.

  2. Atmospheric optical calibration system

    DOEpatents

    Hulstrom, R.L.; Cannon, T.W.

    1988-10-25

    An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions. 7 figs.

  3. Atmospheric optical calibration system

    DOEpatents

    Hulstrom, Roland L.; Cannon, Theodore W.

    1988-01-01

    An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions.

  4. Thermal atmospheric models

    NASA Technical Reports Server (NTRS)

    Johnson, Hollis Ralph

    1987-01-01

    The static thermal atmosphere is described and its predictions are compared to observations both to test the validity of the classic assumptions and to distinguish and describe those spectral features with diagnostic value.

  5. Students 'Weigh' Atmospheric Pollution.

    ERIC Educational Resources Information Center

    Caporaloni, Marina

    1998-01-01

    Describes a procedure developed by students that measures the mass concentration of particles in a polluted urban atmosphere. Uses a portable fan and filters of various materials. Compares students' data with official data. (DDR)

  6. Condensates in Jovian Atmospheres

    NASA Technical Reports Server (NTRS)

    West, R.

    1999-01-01

    Thermochemical equilibrium theory which starts with temperature/pressure profiles, compositional information and thermodynamic data for condensable species in the jovian planet atmospheres predicts layers of condensate clouds in the upper troposphere.

  7. The invention of atmosphere.

    PubMed

    Martin, Craig

    2015-08-01

    The word "atmosphere" was a neologism Willebrord Snellius created for his Latin translation of Simon Stevin's cosmographical writings. Astronomers and mathematical practitioners, such as Snellius and Christoph Scheiner, applying the techniques of Ibn Mu'ādh and Witelo, were the first to use the term in their calculations of the height of vapors that cause twilight. Their understandings of the atmosphere diverged from Aristotelian divisions of the aerial region. From the early years of the seventeenth century, the term was often associated with atomism or corpuscular matter theory. The concept of the atmosphere changed dramatically with the advent of pneumatic experiments in the middle of the seventeenth century. Pierre Gassendi, Walter Charleton, and Robert Boyle transformed the atmosphere of the mathematicians giving it the characteristics of weight, specific gravity, and fluidity, while disputes about its extent and border remained unresolved.

  8. Heterogeneous atmospheric chemistry

    NASA Technical Reports Server (NTRS)

    Schryer, D. R.

    1982-01-01

    The present conference on heterogeneous atmospheric chemistry considers such topics concerning clusters, particles and microparticles as common problems in nucleation and growth, chemical kinetics, and catalysis, chemical reactions with aerosols, electron beam studies of natural and anthropogenic microparticles, and structural studies employing molecular beam techniques, as well as such gas-solid interaction topics as photoassisted reactions, catalyzed photolysis, and heterogeneous catalysis. Also discussed are sulfur dioxide absorption, oxidation, and oxidation inhibition in falling drops, sulfur dioxide/water equilibria, the evidence for heterogeneous catalysis in the atmosphere, the importance of heterogeneous processes to tropospheric chemistry, soot-catalyzed atmospheric reactions, and the concentrations and mechanisms of formation of sulfate in the atmospheric boundary layer.

  9. Middle atmospheric electrodynamics

    NASA Technical Reports Server (NTRS)

    Kelley, M. C.

    1983-01-01

    A review is presented of the advances made during the last few years with respect to the study of the electrodynamics in the earth's middle atmosphere. In a report of the experimental work conducted, attention is given to large middle atmospheric electric fields, the downward coupling of high altitude processes into the middle atmosphere, and upward coupling of tropospheric processes into the middle atmosphere. It is pointed out that new developments in tethered balloons and superpressure balloons should greatly increase the measurement duration of earth-ionospheric potential measurements and of stratospheric electric field measurements in the next few years. Theoretical work considered provides an excellent starting point for study of upward coupling of transient and dc electric fields. Hays and Roble (1979) were the first to construct a model which included orographic features as well as the classical thunderstorm generator.

  10. Our Changing Atmosphere.

    ERIC Educational Resources Information Center

    Clearing, 1988

    1988-01-01

    Summarizes what is known about two major variables involved in certain types of chemical pollution that seem to be changing the structure of the Earth's atmosphere. Discusses the greenhouse effect and the ozone layer. (TW)

  11. SRNL Atmospheric Technologies Group

    SciTech Connect

    Viner, Brian; Parker, Matthew J.

    2016-05-10

    The Savannah River National Laboratory, Atmospheric Technologies Group, conducts a best-in class Applied Meteorology Program to ensure the Department of Energy’s Savannah River Site is operated safely and complies with stringent environmental regulations.

  12. Atmospheric tether mission analyses

    NASA Technical Reports Server (NTRS)

    1996-01-01

    NASA is considering the use of tethered satellites to explore regions of the atmosphere inaccessible to spacecraft or high altitude research balloons. This report summarizes the Lockheed Martin Astronautics (LMA) effort for the engineering study team assessment of an Orbiter-based atmospheric tether mission. Lockheed Martin responsibilities included design recommendations for the deployer and tether, as well as tether dynamic analyses for the mission. Three tether configurations were studied including single line, multistrand (Hoytether) and tape designs.

  13. Dynamics of Triton's atmosphere

    NASA Technical Reports Server (NTRS)

    Ingersoll, Andrew P.

    1990-01-01

    It is argued here that the facts about Triton's atmosphere discovered by the recent Voyager encounter can be explained if Triton, like Mars, has a global, well-structured atmosphere in equilibrium with surface frosts. The subliming frost cap produces a polar anticyclone at low altitudes, with northeastward winds of about 5 m/s within the Ekman boundary layer. The temperature contrast between the cold frost-covered pole and the warm unforested equator produces westward winds at high altitudes.

  14. Study of atmospheric dynamics

    NASA Technical Reports Server (NTRS)

    Mcnider, Richard T.; Christy, John R.; Cox, Gregory N.

    1993-01-01

    In order to better understand the dynamics of the global atmosphere, a data set of precision temperature measurements was developed using the NASA built Microwave Sounding Unit. Modeling research was carried out to validate global model outputs using various satellite data. Idealized flows in a rotating annulus were studied and applied to the general circulation of the atmosphere. Dynamic stratospheric ozone fluctuations were investigated. An extensive bibliography and several reprints are appended.

  15. AC electrophoretic deposition of organic-inorganic composite coatings.

    PubMed

    Yoshioka, T; Chávez-Valdez, A; Roether, J A; Schubert, D W; Boccaccini, A R

    2013-02-15

    Alternating current electrophoretic deposition (AC-EPD) of polyacrylic acid (PAA)-titanium oxide (TiO(2)) nanoparticle composites on stainless steel electrodes was investigated in basic aqueous solution. AC square wave with duty cycle of 80% was applied at a frequency of 1 kHz. FTIR-ATR spectra showed that both AC and direct current (DC) EPD successfully deposited PAA-TiO(2) composites. The deposition rate using AC-EPD was lower than that obtained in direct current DC-EPD. However, the microstructure and surface morphology of the deposited composite coatings were different depending on the type of electric field applied. AC-EPD applied for not more than 5 min led to smooth films without bubble formation, while DC-EPD for 1 min or more showed deposits with microstructural defects possibly as result of water electrolysis. AC-EPD was thus for the first time demonstrated to be a suitable technique to deposit organic-inorganic composite coatings from aqueous suspensions, showing that applying a square wave and frequency of 1 kHz leads to uniform PAA-TiO(2) composite coatings on conductive materials.

  16. Sequential control by speed drive for ac motor

    NASA Astrophysics Data System (ADS)

    Barsoum, Nader

    2012-11-01

    The speed drive for ac motor is widely used in the industrial field to allow direct control for the speed and torque without any feedback from the motor shaft. By using the ABB ACS800 speed drive unit, the speed and torque can be controlled using sequential control method. Sequential control is one of the application control method provided in the ABB ACS800 Drive, where a set of events or action performed in a particular order one after the other to control the speed and torque of the ac motor. It was claimed that sequential control method is using the preset seven constant speeds being provided in ABB ACS800 drive to control the speed and torque in a continuous and sequential manner. The characteristics and features of controlling the speed and torque using sequential control method can be investigated by observing the graphs and curves plotted which are obtained from the practical result. Sequential control can run either in the Direct Torque Control (DTC) or Scalar motor control mode. By using sequential control method, the ABB ACS800 drive can be programmed to run the motor automatically according to the time setting of the seven preset constant speeds. Besides, the intention of this project is to generate a new form of the experimental set up.

  17. Update on bedside ultrasound (US) diagnosis of acute cholecystitis (AC).

    PubMed

    Zenobii, Maria Francesca; Accogli, Esterita; Domanico, Andrea; Arienti, Vincenzo

    2016-03-01

    Acute cholecystitis (AC) represents a principal cause of morbidity worldwide and is one of the most frequent reasons for hospitalization due to gastroenteric tract diseases. AC should be suspected in presence of clinical signs and of gallstones on an imaging study. Upper abdominal US represents the first diagnostic imaging step in the case of suspected AC. Computed tomography (CT) with intravenous contrast (IV) or magnetic resonance imaging (MRI) with gadolinium contrast and technetium hepatobiliary iminodiacetic acid (Tc-HIDA) can be employed to exclude complications. US examination should be performed with right subcostal oblique, with longitudinal and intercostal scans. Normal gallbladder US findings and AC major and minor US signs are described. Polyps, sludge and gallbladder wall thickening represent the more frequent pitfalls and they must be differentiated from stones, duodenal artifacts and many other non-inflammatory conditions that cause wall thickening, respectively. By means of bedside ultrasound, the finding of gallstones in combination with acute pain, when the clinician presses the gallbladder with the US probe (the sonographic Murphy's sign), has a 92.2 % positive predictive value for AC. In our preliminary experience, bedside US-performed by echoscopy (ES) and/or point-of-care US (POCUS) demonstrated good reliability in detecting signs of AC, and was always integrated with physical examination and performed by a skilled operator.

  18. Diagnostics of the Fermilab Tevatron using an AC dipole

    SciTech Connect

    Miyamoto, Ryoichi

    2008-08-01

    The Fermilab Tevatron is currently the world's highest energy colliding beam facility. Its counter-rotating proton and antiproton beams collide at 2 TeV center-of-mass. Delivery of such intense beam fluxes to experiments has required improved knowledge of the Tevatron's beam optical lattice. An oscillating dipole magnet, referred to as an AC dipole, is one of such a tool to non-destructively assess the optical properties of the synchrotron. We discusses development of an AC dipole system for the Tevatron, a fast-oscillating (f ~ 20 kHz) dipole magnet which can be adiabatically turned on and off to establish sustained coherent oscillations of the beam particles without affecting the transverse emittance. By utilizing an existing magnet and a higher power audio amplifier, the cost of the Tevatron AC dipole system became relatively inexpensive. We discuss corrections which must be applied to the driven oscillation measurements to obtain the proper interpretation of beam optical parameters from AC dipole studies. After successful operations of the Tevatron AC dipole system, AC dipole systems, similar to that in the Tevatron, will be build for the CERN LHC. We present several measurements of linear optical parameters (beta function and phase advance) for the Tevatron, as well as studies of non-linear perturbations from sextupole and octupole elements.

  19. Prompt and Delayed Spectroscopy of Ac isotopes around N = 126

    NASA Astrophysics Data System (ADS)

    Hota, S. S.; Lane, G. J.; Reed, M. W.; Mitchell, A. J.; Stuchbery, A. E.; Kibedi, T.; Akber, A. A.; Eriksen, T. E.; Gerathy, M. S.; Palalani, N.; Palazzo, T. R.

    2015-10-01

    Nuclei above Z = 82 and around N = 126 are well described by the spherical shell model, with the attractive proton-neutron residual interactions and particle-octupole vibration coupling resulting in energy-favored, isomeric states occurring along the yrast line. Nuclei up to Z = 88 are mostly well known, but information on Ac (Z = 89) isotopes is limited. We report on high-spin, gamma-ray spectroscopy measurements of 214 , 215 , 216 , 217Ac performed at the Australian National University using the CAESAR array and fusion-evaporation reactions between 12C and 14,15N beams delivered by the 14UD accelerator incident on 204Pb and 209Bi targets. States up to 29/2+ isomers were known previously in 215,217Ac, while only one gamma-ray has been assigned to each of 214,216Ac. New level schemes have now been constructed for 214,216Ac and those for 215,217Ac have been significantly extended. The results will be presented in detail together with semi-empirical shell model calculations that support the proposed level schemes.

  20. Atmospheric Models for Aerocapture

    NASA Technical Reports Server (NTRS)

    Justus, C. G.; Duvall, Aleta L.; Keller, Vernon W.

    2004-01-01

    There are eight destinations in the solar System with sufficient atmosphere for aerocapture to be a viable aeroassist option - Venus, Earth, Mars, Jupiter, Saturn and its moon Titan, Uranus, and Neptune. Engineering-level atmospheric models for four of these targets (Earth, Mars, Titan, and Neptune) have been developed for NASA to support systems analysis studies of potential future aerocapture missions. Development of a similar atmospheric model for Venus has recently commenced. An important capability of all of these models is their ability to simulate quasi-random density perturbations for Monte Carlo analyses in developing guidance, navigation and control algorithm, and for thermal systems design. Similarities and differences among these atmospheric models are presented, with emphasis on the recently developed Neptune model and on planned characteristics of the Venus model. Example applications for aerocapture are also presented and illustrated. Recent updates to the Titan atmospheric model are discussed, in anticipation of applications for trajectory and atmospheric reconstruct of Huygens Probe entry at Titan.

  1. Air ion mobility spectra and concentrations upwind and downwind of overhead AC high voltage power lines

    NASA Astrophysics Data System (ADS)

    Wright, Matthew D.; Buckley, Alison J.; Matthews, James C.; Shallcross, Dudley E.; Henshaw, Denis L.

    2014-10-01

    Corona ions produced by high-voltage power lines (HVPLs) can alter the nearby electrical environment, potentially increasing aerosol charge levels downwind. However, there is a lack of knowledge concerning the concentration and mobility of ions from AC HVPLs and their dispersion away from the line. We present ion concentration and mobility measurements made near AC HVPLs in South-West England. Examples of typical mobility spectra are shown highlighting features commonly observed. Corona was observed during 33 of 46 measurements, at 9 of 11 sites, with positive or ‘bipolar' (both polarities) ion production commonly seen. Ion production usually increases atmospheric concentrations by only a modest amount, but extreme cases can enhance concentration by an order of magnitude or more. A polarity imbalance is required to increase aerosol charge via ion attachment; this was observed on 15 of 24 days when positive corona was observed, but was not seen for negative ions. Ion mobility was higher downwind compared with upwind for both ion polarities, but the increase was not statistically significant. Future work should focus on identifying and characterising ‘heavy-producing' HVPLs, and obtaining results in conditions which may favour negative ion production e.g. high humidity, inclement weather or during nighttime.

  2. The photochemistry of planetary atmospheres

    NASA Technical Reports Server (NTRS)

    Dalgarno, A.

    1988-01-01

    Recent theoretical and observational investigations of photochemical processes in the atmospheres of the planets and their satellites are reviewed. Particular attention is given to the CO2-dominated atmospheres of Mars and Venus, the hydrogen-dominated atmospheres of the Jovian planets, the SO2 atmosphere of Io, and the massive atmospheres of Titan and Triton. The principal reaction paths involved are listed and briefly characterized, and numerical data on atmospheric compositions are given in tables.

  3. Liquid meniscus oscillation and drop ejection by ac voltage, pulsed dc voltage, and superimposing dc to ac voltages

    NASA Astrophysics Data System (ADS)

    Tran, Si Bui Quang; Byun, Doyoung; Nguyen, Vu Dat; Kang, Tae Sam

    2009-08-01

    The electrohydrodynamic (EHD) spraying technique has been utilized in applications such as inkjet printing and mass spectrometry technologies. In this paper, the role of electrical potential signals in jetting and on the oscillation of the meniscus is evaluated. The jetting and the meniscus oscillation behavior are experimentally investigated under ac voltage, ac voltage superimposed on dc voltage, and pulsed dc voltage. Based on this in-depth study of the meniscus behavior under various signals, the optimal signal is implemented to an EHD inkjet head for drop-on-demand operation. For applied ac voltage and ac voltage superimposed on dc voltage, the jetting phenomenon is a dynamic process due to sequential opposite sign signals. The jetting occurs at the end of the oscillation cycle, where the meniscus oscillates upward and arrives at its highest position.

  4. 21 CFR 880.6320 - AC-powered medical examination light.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false AC-powered medical examination light. 880.6320... Miscellaneous Devices § 880.6320 AC-powered medical examination light. (a) Identification. An AC-powered medical examination light is an AC-powered device intended for medical purposes that is used to illuminate...

  5. 21 CFR 880.6320 - AC-powered medical examination light.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false AC-powered medical examination light. 880.6320... Miscellaneous Devices § 880.6320 AC-powered medical examination light. (a) Identification. An AC-powered medical examination light is an AC-powered device intended for medical purposes that is used to illuminate...

  6. Optical Properties of AC60 Materials

    NASA Astrophysics Data System (ADS)

    Martin, Michael C.

    1996-03-01

    The alkali intercalated fullerene system A_1C_60 (A=K, Rb, or Cs) undergoes a number of structural and electronic phase transitions. At elevated temperatures the structure is fcc, but when cooled below ~ 100 ^circC the structure becomes dependent on the sample's thermal treatment. Infrared and Raman spectroscopic investigations into the various resultant phases will be presented.^1,2 Upon slow cooling, the C_60 molecules form linear conducting polymers^3 which break the icosahedral symmetry of the pure fullerene and thus activate many previously silent vibrational modes. This phase is unexpectedly found to be stable in air.^4 At much lower temperatures (30-60K) a magnetic transition has been observed; we will present IR data obtained in this thermal region showing indications of a gap-like feature. If the samples are cooled very rapidly from high temperatures, an insulating phase is formed where even more symmetry breaking occurs. We argue that a dimerization of C_60, Rb_2(C_60)_2, is the likely structure in accord with the vibrational spectra,^2 and recent x-ray results. Both lower-symmetry phases of AC_60 can also be used to help identify the IR- and Raman-silent modes of unperturbed C_60. Work done at the State University of New York at Stony Brook in collaboration with Daniel Koller, Peter W. Stephens, Laszlo Mihaly (State University of New York at Stony Brook), C. Kendziora and A. Rosenberg (Naval Research Laboratory). Supported by NSF Grant DMR9202528. ^1Michael C. Martin, Daniel Koller, Xiaoqun Du, Peter W. Stephens and Laszlo Mihaly, Phys. Rev. B 49, 10 818 (1994). ^2Michael C. Martin, Daniel Koller, A. Rosenberg, C. Kendziora, and L. Mihaly, Phys. Rev. B 51, 3210 (1995). ^3P.W. Stephens, G. Bortel, G. Faigel, M. Tegze, A. Jánossy, S. Pekker, G. Oszlányi and L. Forro, Nature (London) 370, 636 (1994). ^4Daniel Koller, Michael C. Martin, Peter W. Stephens, Laszlo Mihaly, Sandor Pekker, Andras Jánossy, Olivier Chauvet and Laszlo Forro, Appl. Phys. Lett. 66

  7. Evaluation of the modal aerosol model GMXe in the chemistry-climate model GEM-AC

    NASA Astrophysics Data System (ADS)

    Semeniuk, K.; Lupu, A.; Kaminski, J. W.; McConnell, J. C.; O'Neill, N. T.; Tost, H.

    2012-12-01

    We evaluate a modal aerosol model, GMXe, implemented in the atmospheric chemistry-climate model GEM-AC, against global ground-based observations of optical depths and speciated aerosol concentrations. The Global Environmental Multiscale Atmospheric Chemistry model (GEM-AC) is a global, tropospheric-stratospheric chemistry, general circulation model based on the GEM model developed by the Meteorological Service of Canada for operational weather forecasting. Gas-phase chemistry consists in detailed reactions of Ox, NOx, HOx, CO, CH4, NMVOCs, ClOx and BrOx. Tracers are advected using the semi-Lagrangian scheme native to GEM. The vertical transport includes parameterized subgrid scale turbulence and deep convection. Dry deposition is implemented as a flux boundary condition in the vertical diffusion equation. Wet removal comprises both in-cloud and below-cloud scavenging. The Global Modal-aerosol eXtension (GMXe) handles aerosol microphysics and gas-aerosol partitioning. The aerosol size distribution is described by the superposition of 4 hydrophilic and 3 hydrophobic interacting lognormal modes (nucleation, Aitken, accumulation and coarse). Aerosol dynamics includes nucleation, coagulation, and condensation/evaporation. Gas-aerosol partitioning is calculated by the thermodynamic equilibrium model ISORROPIA. The model was run for one year on a 1.5°×1.5° global grid with 73 hybrid levels from the surface to 0.15 hPa. We used aerosol emissions for year 2000 from AeroCom I. The output is compared with aerosol optical depth observations from AERONET, and with measured surface concentrations of sulfate, nitrate and ammonium from CASTNET, EMEP and EANET.

  8. Atmospheric Circulation of Exoplanets

    NASA Astrophysics Data System (ADS)

    Showman, A. P.; Cho, J. Y.-K.; Menou, K.

    2010-12-01

    We survey the basic principles of atmospheric dynamics relevant to explaining existing and future observations of exoplanets, both gas giant and terrestrial. Given the paucity of data on exoplanet atmospheres, our approach is to emphasize fundamental principles and insights gained from solar system studies that are likely to be generalizable to exoplanets. We begin by presenting the hierarchy of basic equations used in atmospheric dynamics, including the Navier-Stokes, primitive, shallow-water, and two-dimensional nondivergent models. We then survey key concepts in atmospheric dynamics, including the importance of planetary rotation, the concept of balance, and simple scaling arguments to show how turbulent interactions generally produce large-scale east-west banding on rotating planets. We next turn to issues specific to giant planets, including their expected interior and atmospheric thermal structures, the implications for their wind patterns, and mechanisms to pump their east-west jets. Hot Jupiter atmospheric dynamics are given particular attention, as these close-in planets have been the subject of most of the concrete developments in the study of exoplanetary atmospheres. We then turn to the basic elements of circulation on terrestrial planets as inferred from solar system studies, including Hadley cells, jet streams, processes that govern the large-scale horizontal temperature contrasts, and climate, and we discuss how these insights may apply to terrestrial exoplanets. Although exoplanets surely possess a greater diversity of circulation regimes than seen on the planets in our solar system, our guiding philosophy is that the multidecade study of solar system planets reviewed here provides a foundation upon which our understanding of more exotic exoplanetary meteorology must build.

  9. Atmospheric rivers in Antarctica?

    NASA Astrophysics Data System (ADS)

    Tsukernik, M.; Lynch, A. H.

    2013-12-01

    Changes and variability in the surface mass balance signify one of the most puzzling questions of the present and future changes in Antarctica. In particular, understanding accumulation in the Eastern part of Antarctic continent presents a great challenge due to sparse and erratic observational network. Several previous publications reported an anomalously high precipitation in May 2009 in Dronning Maud Land, East Antarctica. This anomaly, supported by weather station data from the Princess Elisabeth station, 71°057' S, 23°021' E, 1392m asl, 173 km inland, also corresponded to anomalously high meridional moisture transport across the Southern Ocean inland. Using data from the ERA-Interim reanalysis project and a modified definition for the polar regions, May 2009 event has been classified as an atmospheric river event. Atmospheric river events, traditionally defined in the midlatitudes, are particularly strong and narrow corridors of moisture in middle atmosphere that can result in intense precipitation events once they reach the coast. May 2009 event was the first atmospheric river identified as far south as the Antarctic continent. In this study we perform a detailed analysis of the May 2009 atmospheric river event utilizing data from ERA -Interim and Weather Research and Forecasting (WRF) model simulations. We assess the role of the large-scale atmospheric circulation, particularly the role of the Zonal Wave 3 anomaly. We also investigate the synoptic-scale development of a storm that led to anomalous precipitation event in East Antarctica. We assess the role of upper and lower level forcing with the help of the quasi-geostrophic omega equation. We believe that such in-depth analysis of the dynamics of an atmospheric river event is crucial for better understanding present and future accumulation in the East Antarctica.

  10. LIMITS ON QUAOAR'S ATMOSPHERE

    SciTech Connect

    Fraser, Wesley C.; Gwyn, Stephen; Kavelaars, J. J.; Trujillo, Chad; Stephens, Andrew W.; Gimeno, German

    2013-09-10

    Here we present high cadence photometry taken by the Acquisition Camera on Gemini South, of a close passage by the {approx}540 km radius Kuiper belt object, (50000) Quaoar, of a r' = 20.2 background star. Observations before and after the event show that the apparent impact parameter of the event was 0.''019 {+-} 0.''004, corresponding to a close approach of 580 {+-} 120 km to the center of Quaoar. No signatures of occultation by either Quaoar's limb or its potential atmosphere are detectable in the relative photometry of Quaoar and the target star, which were unresolved during closest approach. From this photometry we are able to put constraints on any potential atmosphere Quaoar might have. Using a Markov chain Monte Carlo and likelihood approach, we place pressure upper limits on sublimation supported, isothermal atmospheres of pure N{sub 2}, CO, and CH{sub 4}. For N{sub 2} and CO, the upper limit surface pressures are 1 and 0.7 {mu}bar, respectively. The surface temperature required for such low sublimation pressures is {approx}33 K, much lower than Quaoar's mean temperature of {approx}44 K measured by others. We conclude that Quaoar cannot have an isothermal N{sub 2} or CO atmosphere. We cannot eliminate the possibility of a CH{sub 4} atmosphere, but place upper surface pressure and mean temperature limits of {approx}138 nbar and {approx}44 K, respectively.

  11. Applications of atmospheric plasmas

    NASA Astrophysics Data System (ADS)

    Oldham, Christopher John

    Surface modification techniques using plasmas have historically been completed in a low pressure environment due to Pd (pressure x gap distance) considerations influencing the behavior of plasma generation. Generally, plasmas produced in a low pressure environment are of a non-thermal or cold nature. The basic feature of non-thermal plasmas is the majority of electrical energy used to generate the plasma is primarily used to produce energetic electrons for generating chemical species. Low pressure plasmas serve many purposes for materials processing. Since the plasma environment is contained within a closed vessel, the plasma can be controlled very easily. Low pressure plasmas have been used in many industries but the complexity associated with the large pumping stations and limitation to batch processing has motivated new work in the area of atmospheric plasmas. Atmospheric plasmas offer both economic and technical justification for use over low pressure plasmas. Since atmospheric plasmas can be operated at ambient conditions, lower costs associated with continuous processing and a decrease in the complexity of equipment validate atmospheric plasma processing as a next generation plasma-aided manufacturing process. In an effort to advance acceptance of atmospheric plasma processing into industry, a process was developed, the dielectric barrier discharge (DBD), in order to generate a homogeneous and non-thermal plasma discharge at ambient conditions. The discharge was applied to the reduction of known food borne pathogens, deposition of thin film materials, and modification of lignocellulosic biomass.

  12. THERMALLY DRIVEN ATMOSPHERIC ESCAPE

    SciTech Connect

    Johnson, Robert E.

    2010-06-20

    Accurately determining the escape rate from a planet's atmosphere is critical for determining its evolution. A large amount of Cassini data is now available for Titan's upper atmosphere and a wealth of data is expected within the next decade on escape from Pluto, Mars, and extra-solar planets. Escape can be driven by upward thermal conduction of energy deposited well below the exobase, as well as by nonthermal processes produced by energy deposited in the exobase region. Recent applications of a model for escape driven by upward thermal conduction, called the slow hydrodynamic escape model, have resulted in surprisingly large loss rates for the atmosphere of Titan, Saturn's largest moon. Based on a molecular kinetic simulation of the exobase region, these rates appear to be orders of magnitude too large. Therefore, the slow hydrodynamic model is evaluated here. It is shown that such a model cannot give a reliable description of the atmospheric temperature profile unless it is coupled to a molecular kinetic description of the exobase region. Therefore, the present escape rates for Titan and Pluto must be re-evaluated using the atmospheric model described here.

  13. Atmospheric trace molecule spectroscopy

    NASA Technical Reports Server (NTRS)

    Farmer, C. B.

    1982-01-01

    The Spacelab investigation entitled Atmospheric Trace Molecule Spectroscopy (ATMOS) is designed to obtain fundamental information related to the chemistry and physics of the Earth's upper atmosphere using the techniques of infrared absorption spectroscopy. There are two principal objectives to be met. The first is the determination, on a global scale, of the compositional structure of the upper atmosphere and its spatial variability. The establishment of this variability represents the first step toward determining the characteristic residence times for the upper atmospheric constituents; the magnitudes of their sources and sinks; and, ultimately, an understanding of their effects on the stability of the stratosphere. The second objective is to provide the high-resolution, calibrated spectral information which is essential for the detailed design of advanced instrumentation for subsequent global monitoring of specific species found to be critical to atmospheric stability. This information will be disseminated in the form of a three dimensional atlas of solar absorption spectra obtained over a range of latitudes, longitudes, and altitudes.

  14. Decomposition of Chemical Chain Molecules with Atmospheric Pressure Plasma

    NASA Astrophysics Data System (ADS)

    Tansli, Murat; Tasal, Erol

    2016-10-01

    Chemical chain molecules' decomposition is an interesting subject area for the atmospheric pressure plasma applications. The effects of the atmospheric pressure argon plasma on 4-((2-methoxyphenyl)Diazenyl)Benzene-1,3,-Diol molecule at room temperature are investigated. This molecule is one of the industrial dye molecules used widely. When considering the ecological life, this molecule will be very harmful and danger. We suggest a different, easy and useful decomposing method for such molecules. Atmospheric pressure plasma jet was principally treated for this decomposing of the molecule. Fourier transform infrared spectrometry (FT-IR) was used to characterization of the molecule after the plasma application to molecule in liquid phase with ethanol and methanol solvents. The atmospheric-pressure plasma jet of argon (Ar) as non-equilibrium has been formed by ac-power generator with frequency - 24 kHz and voltage - 12 kV. Characterizations for solutions prepared with ethanol and methanol solvents of molecule have been examined after applying (duration: 3 minutes) the atmospheric pressure plasma jet. The molecule was broken at 6C-7N =8N-9C stretching peak after the plasma treatment. The new plasma photo-products for ethanol and methanol solutions were produced as 6C-7N-8N =9C (strong, varying) and 12C =17O (strong, wide) stretching peaks.

  15. Apple MdACS6 Regulates Ethylene Biosynthesis During Fruit Development Involving Ethylene-Responsive Factor.

    PubMed

    Li, Tong; Tan, Dongmei; Liu, Zhi; Jiang, Zhongyu; Wei, Yun; Zhang, Lichao; Li, Xinyue; Yuan, Hui; Wang, Aide

    2015-10-01

    Ethylene biosynthesis in plants involves different 1-aminocyclopropane-1-carboxylic acid synthase (ACS) genes. The regulation of each ACS gene during fruit development is unclear. Here, we characterized another apple (Malus×domestica) ACS gene, MdACS6. The transcript of MdACS6 was observed not only in fruits but also in other tissues. During fruit development, MdACS6 was initiated at a much earlier stage, whereas MdACS3a and MdACS1 began to be expressed at 35 d before harvest and immediateley after harvest, respectively. Moreover, the enzyme activity of MdACS6 was significantly lower than that of MdACS3a and MdACS1, accounting for the low ethylene biosynthesis in young fruits. Overexpression of MdACS6 (MdACS6-OE) by transient assay in apple showed enhanced ethylene production, and MdACS3a was induced in MdACS6-OE fruits but not in control fruits. In MdACS6 apple fruits silenced by the virus-induced gene silencing (VIGS) system (MdACS6-AN), neither ethylene production nor MdACS3a transcript was detectable. In order to explore the mechanism through which MdACS3a was induced in MdACS6-OE fruits, we investigated the expression of apple ethylene-responsive factor (ERF) genes. The results showed that the expression of MdERF2 was induced in MdACS6-OE fruits and inhibited in MdACS6-AN fruits. Yeast one-hybrid assay showed that MdERF2 protein could bind to the promoter of MdACS3a. Moreover, down-regulation of MdERF2 in apple flesh callus led to a decrease of MdACS3a expression, demonstrating the regulation of MdERF2 on MdACS3a. The mechanism through which MdACS6 regulates the action of MdACS3a was discussed.

  16. Martian atmospheric radiation budget

    NASA Technical Reports Server (NTRS)

    Lindner, Bernhard Lee

    1994-01-01

    A computer model is used to study the radiative transfer of the martian winter-polar atmosphere. Solar heating at winter-polar latitudes is provided predominately by dust. For normal, low-dust conditions, CO2 provides almost as much heating as dust. Most heating by CO2 in the winter polar atmosphere is provided by the 2.7 micron band between 10 km and 30 km altitude, and by the 2.0 micron band below 10 km. The weak 1.3 micron band provides some significant heating near the surface. The minor CO2 bands at 1.4, 1.6, 4.8 and 5.2 micron are all optically thin, and produce negligible heating. O3 provides less than 10 percent of the total heating. Atmospheric cooling is predominantly thermal emission by dust, although CO2 15 micron band emission is important above 20 km altitude.

  17. Atmospheric engineering of Mars

    NASA Technical Reports Server (NTRS)

    Macelroy, R. D.; Averner, M. M.

    1976-01-01

    The feasibility of creating a breathable atmosphere on Mars was studied. Assuming that indigenous life is absent, and that human habitation will prove economically justifiable, several methods of introducing oxygen were considered. On the basis of energy requirements, photosynthetic oxygen production appears to be reasonable, assuming that the amounts of water, carbon dioxide, and mineral nutrients available on the Martian surface would be adequate for the growth of photosynthetic microorganisms. However, optimum rates of O2 formation could occur only after a significant increase in average temperature and in atmospheric mass. The generation of a runaway greenhouse/advective effect was considered. However, neither the energy requirement nor the time constant for initiation could be calculated. There appear to be no insuperable obstacles to the conversion of the Martian atmosphere to one containing oxygen, but the conversion would require many thousands of years.

  18. Atmospheric Pseudohalogen Chemistry

    NASA Technical Reports Server (NTRS)

    Lary, David John

    2004-01-01

    Hydrogen cyanide is not usually considered in atmospheric chemical models. The paper presents three reasons why hydrogen cyanide is likely to be significant for atmospheric chemistry. Firstly, HCN is a product and marker of biomass burning. Secondly, it is also likely that lightning is producing HCN, and as HCN is sparingly soluble it could be a useful long-lived "smoking gun" marker of lightning activity. Thirdly, the chemical decomposition of HCN leads to the production of small amounts of the cyanide (CN) and NCO radicals. The NCO radical can be photolyzed in the visible portion of the spectrum yielding nitrogen atoms (N). The production of nitrogen atoms is significant as it leads to the titration of total nitrogen from the atmosphere via N+N->N2, where N2 is molecular nitrogen.

  19. Selectivity of hydrogen peroxide decomposition towards hydroxyl radicals in catalytic wet peroxide oxidation (CWPO) over Fe/AC catalysts.

    PubMed

    Rey, A; Bahamonde, A; Casas, J A; Rodríguez, J J

    2010-01-01

    Two Fe/AC catalysts prepared with different iron precursors (iron nitrate and iron pentacarbonyl) and the same AC support have been tested in H(2)O(2) decomposition in presence and absence of methanol, a known strong scavenger of hydroxyl radicals, to investigate the selectivity towards .OH formation in this reaction and their behavior in the CWPO of phenol. The catalyst prepared with iron nitrate, with the most oxidized surface and the highest Fe surface content, seems to favor a higher selectivity towards .OH formation in CWPO allowing for complete phenol conversion and a significant TOC removal, with the highest mineralization degree at 50 degrees C and atmospheric pressure. Fe/AC catalysts were more efficient in the CWPO of phenol than in methanol presence due to a better use of the oxidant since adsorbed phenol on catalyst surface minimizes inefficient H(2)O(2) decomposition to H(2)O and O(2)(g). The influence of the initial H(2)O(2) concentration on phenol oxidation with this catalyst was also studied. A theoretical stoichiometric amount of H(2)O(2) for complete oxidation of phenol was chosen as the best starting concentration since auto-scavenging reactions can be minimized and it is sufficient for oxidizing phenol and the aromatic intermediates.

  20. Dissipation in Planetary Atmospheres

    NASA Astrophysics Data System (ADS)

    Schubert, Gerald; Mitchell, J.

    2012-10-01

    The net radiative entropy flux of a planet is negative because atmospheres absorb solar radiation at a higher temperature than the temperature at which they re-emit an equal amount of longwave radiation to space. If in the long term the entropy of an atmosphere is constant, the radiative entropy loss must be balanced by the entropy production associated with thermally direct heat transports and dissipation. Given estimates of the thermally direct sources of entropy production and the temperature at which dissipation occurs, this determines the rate of dissipation in an atmosphere. It is estimated that the entropy production due to dissipation in the atmospheres of Venus, Earth, Mars and Titan occurs at the rate, respectively, of about ≤23, 29, 2, and ≤4 mW m-2 K-1. If the dissipation in Earth’s atmosphere occurs between temperatures of 250 K and 288 K the dissipation rate must lie between 7.3 and 8.4 W m- 2, consistent with other recent estimates. The terrestrial heat engine operates with an efficiency of about 60% of the Carnot efficiency. Sources of dissipation in planetary atmospheres are highly uncertain, even for Earth. For Earth, frictional dissipation in rainfall is comparable to the turbulent dissipation of kinetic energy. Rainfall might also be a significant source of dissipation on Titan but it is not likely to be important for Mars or Venus. The breaking of upward propagating internal gravity waves generated by convection and flow over the surface topography is another source of dissipation and is possibly dominant on Venus.