WorldWideScience

Sample records for pre ivc hydrogen-fueled

  1. Hydrogen system (hydrogen fuels feasibility)

    International Nuclear Information System (INIS)

    Guarna, S.

    1991-07-01

    This feasibility study on the production and use of hydrogen fuels for industry and domestic purposes includes the following aspects: physical and chemical properties of hydrogen; production methods steam reforming of natural gas, hydrolysis of water; liquid and gaseous hydrogen transportation and storage (hydrogen-hydride technology); environmental impacts, safety and economics of hydrogen fuel cells for power generation and hydrogen automotive fuels; relevant international research programs

  2. Progress in hydrogen fueled busses

    International Nuclear Information System (INIS)

    Scott, P.B.; Mazaika, D.M.; Tyler, T.

    2004-01-01

    'Full text:' The Thor/ISE fuel cell bus has been in demonstration and revenue service during 2002-2003 at sites including SunLine Transit, Chula Vista Transit, Los Angeles County Metropolitan Transit Authority, and AC Transit in Oakland. By taking advantage of ISE's advanced hybrid-electric drive technology, this 30-foot bus operates with a much smaller fuel cell than those used in other buses of this class. Further, stress on the fuel cell is diminished. Based on the exceptional performance of this prototype bus, the transit agencies listed above have concluded that hybrid electric hydrogen fueled buses are attractive. Two types of hydrogen fueled hybrid electric buses will be described: - fuel cell powered, and - HICE (Hydrogen Internal Combustion Engine) This progress report will include: 1. Experience with the Thor/ISE fuel cell bus, including results from revenue service at two transit locations, 2. Design and fabrication status of the advanced fuel cell buses being built for AC Transit and SunLine Transit, 3. Design and fabrication status of the prototype HHICE (Hybrid electric Hydrogen fueled Internal Combustion Engine) bus that uses a Ford hydrogen burning engine, mated to a generator, rather than a fuel cell. Other than the engine, the drive train in the HHICE bus is nearly identical to that of a fuel cell hybrid-electric bus. Canadian participation in the HHICE bus is extensive, it is a New Flyer platform and will be winter tested in Winnipeg. (author)

  3. Hydrogen fuel cell power system

    International Nuclear Information System (INIS)

    Lam, A.W.

    2004-01-01

    'Full text:' Batteries are typically a necessary and prime component of any DC power system, providing a source of on-demand stored energy with proven reliability. The integration of batteries and basic fuel cells for mobile and stationary utility applications poses a new challenge. For high value applications, the specification and operating requirements for this hybrid module differ from conventional requirements as the module must withstand extreme weather conditions and provide extreme reliability. As an electric utility company, BCHydro has embarked in the development and application of a Hydrogen Fuel Cell Power Supply (HFCPS) for field trial. A Proton Exchange Membrane (PEM)- type fuel cell including power electronic modules are mounted in a standard 19-inch rack that provides 48V, 24V, 12V DC and 120V AC outputs. The hydrogen supply consists of hydrogen bottles and regulating devices to provide a continuous fuel source to the power modules. Many tests and evaluations have been done to ensure the HFCPS package is robust and suitable for electric utility grade operation. A field trial demonstrating this standalone system addressed reliability, durability, and installation concerns as well as developed the overall system operating procedures. (author)

  4. Hydrogen, fuel of the future?

    International Nuclear Information System (INIS)

    Bello, B.

    2008-01-01

    The European project HyWays has drawn out the road map of hydrogen energy development in Europe. The impact of this new energy vector on the security of energy supplies, on the abatement of greenhouse gases and on the economy should be important in the future. This article summarizes the main conclusions of the HyWays study: CO 2 emissions, hydrogen production mix, oil saving abatement, economic analysis, contribution of hydrogen to the development of renewable energies, hydrogen uses, development of regional demand and of users' centers, transport and distribution. The proposals of the HyWays consortium are as follows: implementing a strong public/private European partnership to reach the goals, favoring market penetration, developing training, tax exemption on hydrogen in the initial phase for a partial compensation of the cost difference, inciting public fleets to purchase hydrogen-fueled vehicles, using synergies with other technologies (vehicles with internal combustion engines, hybrid vehicles, biofuels of second generation..), harmonizing hydrogen national regulations at the European scale. (J.S.)

  5. Hydrogen fuel cell engines and related technologies

    Science.gov (United States)

    2001-12-01

    The manual documents the first training course developed on the use of hydrogen fuel cells in transportation. The manual contains eleven modules covering hydrogen properties, use and safety; fuel cell technology and its systems, fuel cell engine desi...

  6. Fundamentals: IVC and Computer Science

    NARCIS (Netherlands)

    Gozalvez, Javier; Haerri, Jerome; Hartenstein, Hannes; Heijenk, Geert; Kargl, Frank; Petit, Jonathan; Scheuermann, Björn; Tieler, Tessa; Altintas, O.; Dressler, F.; Hartenstein, H.; Tonguz, O.K.

    The working group on “Fundamentals: IVC and Computer Science‿ discussed the lasting value of achieved research results as well as potential future directions in the field of inter- vehicular communication. Two major themes ‘with variations’ were the dependence on a specific technology (particularly

  7. Kicking the habit[Hydrogen fuel

    Energy Technology Data Exchange (ETDEWEB)

    Jones, N.; Lawton, G.; Pearce, F.

    2000-11-25

    This article focuses on the use of clean non-polluting hydrogen fuel as opposed to the use of fossil fuels which ties western nations to the Middle East. Details are given of Iceland's plans to use hydrogen fuelled buses, cars, trucks and trawlers, car manufacturers' options of using internal combustion engines burning hydrogen and hydrogen fuel cells, and the production of hydrogen using electrolysis of water and steam reforming of hydrocarbons. The 'Green Dream' of pollution-free hydrogen production, the use of solar energy for renewable hydrogen production in California, and problems associated with hydrogen storage are discussed.

  8. Water reactive hydrogen fuel cell power system

    Science.gov (United States)

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

    2014-01-21

    A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into a fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

  9. The Importance of Individual Ventilation Cottage (IVC) System

    International Nuclear Information System (INIS)

    Anee Suryani Sued; Fazliana Mohd Saaya; Mohd Ramli Ibrahim; Shafii Khamis

    2015-01-01

    Experimental animals such as rats and mice are used in scientific research, especially in research related to drugs, must be able to give the right decisions and authentic. The results are not accurate and authentic will harm humans, especially in pre-clinical studies of drugs (drug) trial. Therefore, the system of individual ventilated cages (IVC) has been developed in the Malaysian Nuclear Agency to ensure that animal experiments are always at the level of quality, healthy and disease free. IVC system was developed to replace conventional animal cage systems that have been used previously. The use of IVC systems in breed and maintain rats and mice to obtain disease-free animal, the animal known as SPF (Specific pathogen free animals). For this purpose, the IVC system using 'bedding' typical food and animal pests that have been purified to ensure that it meets the intended use of the system perfectly. In addition, system privileges are through the ventilation system that can isolate the one-way air enters and exits for each cage, and equipped with a HEPA filter (High -Efficiency-Particulate Air) filter which can prevent contamination of microorganisms for ventilation in the cage and the air in the vicinity , Through the use of IVC system, the quality and health of experimental animals that are bred and used in the Medical Technology Division can be improved and so can guarantee the accuracy and validity of the results of research conducted. (author)

  10. Hydrogen fuel cells for cars and buses

    NARCIS (Netherlands)

    Janssen, L.J.J.

    2007-01-01

    The use of hydrogen fuel cells for cars is strongly promoted by the governments of many countries and by international organizations like the European Community. The electrochem. behavior of the most promising fuel cell (polymer electrolyte membrane fuel cell, PEMFC) is critically discussed, based

  11. National FCEV and Hydrogen Fueling Station Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Bush, Brian; Melaina, Marc

    2016-06-09

    This presentation provides a summary of the FY16 activities and accomplishments for NREL's national fuel cell electric vehicle (FCEV) and hydrogen fueling station scenarios project. It was presented at the U.S. Department of Energy Hydrogen and Fuel Cells Program 2016 Annual Merit Review and Peer Evaluation Meeting on June 9, 2016, in Washington, D.C.

  12. Hydrogen Fuel Cells: Part of the Solution

    Science.gov (United States)

    Busby, Joe R.; Altork, Linh Nguyen

    2010-01-01

    With the decreasing availability of oil and the perpetual dependence on foreign-controlled resources, many people around the world are beginning to insist on alternative fuel sources. Hydrogen fuel cell technology is one answer to this demand. Although modern fuel cell technology has existed for over a century, the technology is only now becoming…

  13. An Opportunity for Hydrogen Fueled Supersonic Airliners

    Directory of Open Access Journals (Sweden)

    Alex Forbes

    2011-02-01

    Full Text Available This paper takes a new look at the prospects for developing supersonic civil airliners, considering global demographics, climate change issues, fuel prices and technological advances. Dramatic changes have occurred in the demographics, economics, and market intensity of the Eastern Hemisphere since the 1990s. Carbon reduction imperatives provide a major incentive to invest in developing hydrogen-fueled airliners. The “point-to-point” air route architecture has proved viable with long range mid-size airliners. With a cruise Mach number of 1.4, a large number of destinations become viable for overland supersonic flight. A conceptual design process is used to estimate cost per seat mile for a range of hydrocarbon and hydrogen fuel costs. An argument based on the ideal shape for minimal wave drag, estimates the drag penalty from using hydrogen. Viable aircraft geometries are shown to exist, that match the theoretical ideal shape, showing that the drag estimate is achievable. Conservative design arguments and market estimates suggest that hydrogen-fueled airliners can achieve seat-mile costs low enough to open a large worldwide market and justify a viable fleet size.

  14. Hydrogen & fuel cells: advances in transportation and power

    National Research Council Canada - National Science Library

    Hordeski, Michael F

    2009-01-01

    ... race, it became more of an economics issue since as long as petroleum was available and cheap there was no need to develop a hydrogen technology. Now, we see much more investment in fuel cell technology, hydrogen fueled vehicles and even hydrogen fuel stations. The technology is being pushed by economics as oil prices continue to rise with dwind...

  15. Hydrogen Fuel Cell development in Columbia (SC)

    Energy Technology Data Exchange (ETDEWEB)

    Reifsnider, Kenneth [Univ. of South Carolina, Columbia, SC (United States); Chen, Fanglin [Univ. of South Carolina, Columbia, SC (United States); Popov, Branko [Univ. of South Carolina, Columbia, SC (United States); Chao, Yuh [Univ. of South Carolina, Columbia, SC (United States); Xue, Xingjian [Univ. of South Carolina, Columbia, SC (United States)

    2012-09-15

    This is an update to the final report filed after the extension of this program to May of 2011. The activities of the present program contributed to the goals and objectives of the Fuel Cell element of the Hydrogen, Fuel Cells and Infrastructure Technologies Program of the Department of Energy through five sub-projects. Three of these projects have focused on PEM cells, addressing the creation of carbon-based metal-free catalysts, the development of durable seals, and an effort to understand contaminant adsorption/reaction/transport/performance relationships at low contaminant levels in PEM cells. Two programs addressed barriers in SOFCs; an effort to create a new symmetrical and direct hydrocarbon fuel SOFC designs with greatly increased durability, efficiency, and ease of manufacturing, and an effort to create a multiphysics engineering durability model based on electrochemical impedance spectroscopy interpretations that associate the micro-details of how a fuel cell is made and their history of (individual) use with specific prognosis for long term performance, resulting in attendant reductions in design, manufacturing, and maintenance costs and increases in reliability and durability.

  16. Safety risks of hydrogen fuel for applications in transportation vehicles.

    Science.gov (United States)

    2009-04-01

    Combustion of hydrocarbon fuels in many practical applications produces pollutants that are harmful to human health and environment. Hydrogen fuel is considered to be a potential answer to the clean energy demands, especially with the advances in fue...

  17. IVC filter retrieval in adolescents: experience in a tertiary pediatric center.

    Science.gov (United States)

    Guzman, Anthony K; Zahra, Mahmoud; Trerotola, Scott O; Raffini, Leslie J; Itkin, Maxim; Keller, Marc S; Cahill, Anne Marie

    2016-04-01

    Inferior vena cava (IVC) filters are commonly implanted with the intent to prevent life-threatening pulmonary embolism in at-risk patients with contraindications to anticoagulation. Various studies have reported increases in the rate of venous thromboembolism within the pediatric population. The utility and safety of IVC filters in children has not yet been fully defined. To describe the technique and adjunctive maneuvers of IVC filter removal in children, demonstrate its technical success and identify complications. A retrospective 10-year review was performed of 20 children (13 male, 7 female), mean age: 15.1 years (range: 12-19 years), who underwent IVC filter retrieval. Eleven of 20 (55%) were placed in our institution. Electronic medical records were reviewed for filter characteristics, retrieval technique, technical success and complications. The technical success rate was 100%. Placement indications included: deep venous thrombosis with a contraindication to anticoagulation (10/20, 50%), free-floating thrombus (4/20, 20%), post-trauma pulmonary embolism prophylaxis (3/20, 15%) and pre-thrombolysis pulmonary patient (1/20, 5%). The mean implantation period was 63 days (range: 20-270 days). Standard retrieval was performed in 17/20 patients (85%). Adjunctive techniques were performed in 3/20 patients (15%) and included the double-snare technique, balloon assistance and endobronchial forceps retrieval. Median procedure time was 60 min (range: 45-240 min). Pre-retrieval cavogram demonstrated filter tilt in 5/20 patients (25%) with a mean angle of 17° (range: 8-40). Pre-retrieval CT demonstrated strut wall penetration and tip embedment in one patient each. There were two procedure-related complications: IVC mural dissection noted on venography in one patient and snare catheter fracture requiring retrieval in one patient. There were no early or late complications. In children, IVC filter retrieval can be performed safely but may be challenging, especially in

  18. Respiratory-Induced Haemodynamic Changes: A Contributing Factor to IVC Filter Penetration

    International Nuclear Information System (INIS)

    Laborda, Alicia; Kuo, William T.; Ioakeim, Ignatios; De Blas, Ignacio; Malvè, Mauro; Lahuerta, Celia; De Gregorio, Miguel A.

    2015-01-01

    PurposeThe purpose of the study is to evaluate the influence of respiratory-induced vena caval hemodynamic changes on filter migration/penetration.Materials and MethodsAfter placement of either a Gunther Tulip or Celect IVC filter, 101 consecutive patients scheduled for filter retrieval were prospectively enrolled in this study. Pre-retrieval CT scans were used to assess filter complications and to calculate cross-sectional area in three locations: at level of filter strut fixation, 3 cm above and 3 cm below. A 3D finite element simulation was constructed on these data and direct IVC pressure was recorded during filter retrieval. Cross-sectional areas and pressures of the vena cava were measured during neutral breathing and in Valsalva maneuver and identified filter complications were recorded. A statistical analysis of these variables was then performed.ResultsDuring Valsalva maneuvers, a 60 % decrease of the IVC cross-sectional area and a fivefold increase in the IVC pressure were identified (p < 0.001). There was a statistically significant difference in the reduction of the cross-sectional area at the filter strut level (p < 0.001) in patient with filter penetration. Difficulty in filter retrieval was higher in penetrated or tilted filters (p < 0.001; p = 0.005). 3D computational models showed significant IVC deformation around the filter during Valsalva maneuver.ConclusionCaval morphology and hemodynamics are clearly affected by Valsalva maneuvers. A physiological reduction of IVC cross-sectional area is associated with higher risk of filter penetration, despite short dwell times. Physiologic data should be used to improve future filter designs to remain safely implanted over longer dwell times

  19. Respiratory-Induced Haemodynamic Changes: A Contributing Factor to IVC Filter Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Laborda, Alicia, E-mail: alaborda@unizar.es [Universidad de Zaragoza, Minimally Invasive Techniques Research Group (GITMI) (Spain); Kuo, William T., E-mail: wkuo@stanford.edu [Stanford University Medical Center, Division of Vascular and Interventional Radiology (United States); Ioakeim, Ignatios, E-mail: ignacio.ioakim@hotmail.es [Universidad de Zaragoza, Minimally Invasive Techniques Research Group (GITMI) (Spain); De Blas, Ignacio, E-mail: deblas@unizar.es [Universidad de Zaragoza, Unit of Infectious Diseases and Epidemiology, Department of Animal Pathology (Spain); Malvè, Mauro, E-mail: mauro.malve@unavarra.es [Universidad Pública de Navarra, Department of Mechanical, Energy and Materials Engineering (Spain); Lahuerta, Celia, E-mail: celialahuerta@gmail.com; De Gregorio, Miguel A., E-mail: mgregori@unizar.es [Universidad de Zaragoza, Minimally Invasive Techniques Research Group (GITMI) (Spain)

    2015-10-15

    PurposeThe purpose of the study is to evaluate the influence of respiratory-induced vena caval hemodynamic changes on filter migration/penetration.Materials and MethodsAfter placement of either a Gunther Tulip or Celect IVC filter, 101 consecutive patients scheduled for filter retrieval were prospectively enrolled in this study. Pre-retrieval CT scans were used to assess filter complications and to calculate cross-sectional area in three locations: at level of filter strut fixation, 3 cm above and 3 cm below. A 3D finite element simulation was constructed on these data and direct IVC pressure was recorded during filter retrieval. Cross-sectional areas and pressures of the vena cava were measured during neutral breathing and in Valsalva maneuver and identified filter complications were recorded. A statistical analysis of these variables was then performed.ResultsDuring Valsalva maneuvers, a 60 % decrease of the IVC cross-sectional area and a fivefold increase in the IVC pressure were identified (p < 0.001). There was a statistically significant difference in the reduction of the cross-sectional area at the filter strut level (p < 0.001) in patient with filter penetration. Difficulty in filter retrieval was higher in penetrated or tilted filters (p < 0.001; p = 0.005). 3D computational models showed significant IVC deformation around the filter during Valsalva maneuver.ConclusionCaval morphology and hemodynamics are clearly affected by Valsalva maneuvers. A physiological reduction of IVC cross-sectional area is associated with higher risk of filter penetration, despite short dwell times. Physiologic data should be used to improve future filter designs to remain safely implanted over longer dwell times.

  20. Solar Hydrogen Fuel Cell Projects at Brooklyn Tech

    Science.gov (United States)

    Fedotov, Alex; Farah, Shadia; Farley, Daithi; Ghani, Naureen; Kuo, Emmy; Aponte, Cecielo; Abrescia, Leo; Kwan, Laiyee; Khan, Ussamah; Khizner, Felix; Yam, Anthony; Sakeeb, Khan; Grey, Daniel; Anika, Zarin; Issa, Fouad; Boussayoud, Chayama; Abdeldayem, Mahmoud; Zhang, Alvin; Chen, Kelin; Chan, Kameron Chuen; Roytman, Viktor; Yee, Michael

    2010-01-01

    This article describes the projects on solar hydrogen powered vehicles using water as fuel conducted by teams at Brooklyn Technical High School. Their investigations into the pure and applied chemical thermodynamics of hydrogen fuel cells and bio-inspired devices have been consolidated in a new and emerging sub-discipline that they define as solar…

  1. OTEC to hydrogen fuel cells - A solar energy breakthrough

    Science.gov (United States)

    Roney, J. R.

    Recent advances in fuel cell technology and development are discussed, which will enhance the Ocean Thermal Energy Conversion (OTEC)-hydrogen-fuel cell mode of energy utilization. Hydrogen obtained from the ocean solar thermal resources can either be liquified or converted to ammonia, thus providing a convenient mode of transport, similar to that of liquid petroleum. The hydrogen fuel cell can convert hydrogen to electric power at a wide range of scale, feeding either centralized or distributed systems. Although this system of hydrogen energy production and delivery has been examined with respect to the U.S.A., the international market, and especially developing countries, may represent the greatest opportunity for these future generating units.

  2. Hydrogen fueling demonstration projects using compact PSA purification

    International Nuclear Information System (INIS)

    Ng, E.; Smith, T.

    2004-01-01

    'Full text:' Hydrogen fueling demonstration projects are critical to the success of hydrogen as an automotive fuel by building public awareness and demonstrating the technology required to produce, store, and dispense hydrogen. Over 75 of these demonstration projects have been undertaken or are in the planning stages world-wide, sponsored by both the public and private sectors. Each of these projects represents a unique combination of sponsors, participants, geographic location, and hydrogen production pathway. QuestAir Technologies Inc., as the industry leader in compact pressure swing adsorption equipment for purifying hydrogen, has participated in four hydrogen fueling demonstration projects with a variety of partners and in North America and Japan. QuestAir's experiences as a participant in the planning, construction, and commissioning of these demonstration projects will be presented in this paper. The unique challenges of each project and the critical success factors that must to be considered for successful deployment of high-profile, international, and multi-vendor collaborations will also be discussed. The paper will also provide insights on the requirements for hydrogen fueling demonstration projects in the future. (author)

  3. Investigation of combustion characteristics of methane-hydrogen fuels

    Science.gov (United States)

    Vetkin, A. V.; Suris, A. L.; Litvinova, O. A.

    2015-01-01

    Numerical investigations of combustion characteristics of methane-hydrogen fuel used at present in tube furnaces of some petroleum refineries are carried out and possible problems related to change-over of existing furnaces from natural gas to methane-hydrogen fuel are analyzed. The effect of the composition of the blended fuel, associated temperature and emissivity of combustion products, temperature of combustion chamber walls, mean beam length, and heat release on variation in the radiation heat flux is investigated. The methane concentration varied from 0 to 100%. The investigations were carried out both at arbitrary given gas temperatures and at effective temperatures determined based on solving a set of equations at various heat-release rates of the combustion chamber and depended on the adiabatic combustion temperature and the temperature at the chamber output. The approximation dependence for estimation of the radiation heat exchange rate in the radiant chamber of the furnace at change-over to fuel with a greater hydrogen content is obtained. Hottel data were applied in the present work in connection with the impossibility to use approximated formulas recommended by the normative method for heat calculation of boilers to determine the gas emissivity, which are limited by the relationship of partial pressures of water steam and carbon dioxide in combustion products . The effect of the methane-hydrogen fuel on the equilibrium concentration of nitrogen oxides is also investigated.

  4. Premixer Design for High Hydrogen Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Benjamin P. Lacy; Keith R. McManus; Balachandar Varatharajan; Biswadip Shome

    2005-12-16

    This 21-month project translated DLN technology to the unique properties of high hydrogen content IGCC fuels, and yielded designs in preparation for a future testing and validation phase. Fundamental flame characterization, mixing, and flame property measurement experiments were conducted to tailor computational design tools and criteria to create a framework for predicting nozzle operability (e.g., flame stabilization, emissions, resistance to flashback/flame-holding and auto-ignition). This framework was then used to establish, rank, and evaluate potential solutions to the operability challenges of IGCC combustion. The leading contenders were studied and developed with the most promising concepts evaluated via computational fluid dynamics (CFD) modeling and using the design rules generated by the fundamental experiments, as well as using GE's combustion design tools and practices. Finally, the project scoped the necessary steps required to carry the design through mechanical and durability review, testing, and validation, towards full demonstration of this revolutionary technology. This project was carried out in three linked tasks with the following results. (1) Develop conceptual designs of premixer and down-select the promising options. This task defined the ''gap'' between existing design capabilities and the targeted range of IGCC fuel compositions and evaluated the current capability of DLN pre-mixer designs when operated at similar conditions. Two concepts (1) swirl based and (2) multiple point lean direct injection based premixers were selected via a QFD from 13 potential design concepts. (2) Carry out CFD on chosen options (1 or 2) to evaluate operability risks. This task developed the leading options down-selected in Task 1. Both a GE15 swozzle based premixer and a lean direct injection concept were examined by performing a detailed CFD study wherein the aerodynamics of the design, together with the chemical kinetics of the

  5. Case of a Misplaced IVC Filter: A Lesson to Learn

    International Nuclear Information System (INIS)

    Sharma, Sanjay; Mukund, Amar; Agarwal, Sandeep; Srivastava, Deep N.

    2010-01-01

    The inferior vena cava (IVC) filter insertion is a well established procedure to prevent significant pulmonary embolism in selected situations. It is generally considered straight forward without significant complications. We report an interesting case of a young postpartum woman in whom an IVC filter was misplaced in the right gonadal vein. This complication is only rarely reported. Presence of prominent right gonadal vein must always be kept in mind during trans-jugular placement of infra renal filter in the IVC in post partum women.

  6. Hydrogen Fueling Station in Honolulu, Hawaii Feasibility Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Porter Hill; Michael Penev

    2014-08-01

    The Department of Energy Hydrogen & Fuel Cells Program Plan (September 2011) identifies the use of hydrogen for government and fleet electric vehicles as a key step for achieving “reduced greenhouse gas emissions; reduced oil consumption; expanded use of renewable power …; highly efficient energy conversion; fuel flexibility …; reduced air pollution; and highly reliable grid-support.” This report synthesizes several pieces of existing information that can inform a decision regarding the viability of deploying a hydrogen (H2) fueling station at the Fort Armstrong site in Honolulu, Hawaii.

  7. Thermal characteristics during hydrogen fueling process of type IV cylinder

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Chan [Department of Fire and Disaster Prevention, Kyungil University, 33, Buhori, Hayang, Kyungsan 712-701 (Korea); Lee, Seung Hoon; Yoon, Kee Bong [Department of Mechanical Engineering, Chung Ang University, 221, Huksuk, Dongjak, Seoul 156-756 (Korea)

    2010-07-15

    Temperature increase during hydrogen fueling process is a significant safety concern of a high pressure hydrogen vessel. Hence, thermal characteristics of a Type IV cylinder during hydrogen filling process need to be understood. In this study, a series of experiments were conducted to quantify the temperature change of the cylinder during hydrogen filling to 35 MPa. Computational fluid dynamics (CFD) analysis was also conducted to simulate the conditions of the experiments. The results predicted by the CFD analysis show reasonable agreement with the experiments and the discrepancy between the CFD results and experimental results decrease with higher initial gas pressures. The upper and the lower parts of the vessel showed a temperature difference in the vertical direction. The upper gas temperature was higher than that of the lower part due to the buoyancy effect in the vessel. The maximum gas temperature was higher than the maximum temperature allowed in the ISO safety code (85 C) for the case in which the vessel was pressurized from 0 MPa to 35 MPa. This work contributes to the understanding of the thermal flow characteristics of the hydrogen filling process and notes that additional efforts should be made to guarantee the safety of a type IV cylinder during the hydrogen fueling process. (author)

  8. Experimental results with hydrogen fueled internal combustion engines

    Science.gov (United States)

    De Boer, P. C. T.; Mclean, W. J.; Homan, H. S.

    1975-01-01

    The paper focuses on the most important experimental findings for hydrogen-fueled internal combustion engines, with particular reference to the application of these findings to the assessment of the potential of hydrogen engines. Emphasis is on the various tradeoffs that can be made, such as between maximum efficiency, maximum power, and minimum NO emissions. The various possibilities for induction and ignition are described. Some projections are made about areas in which hydrogen engines may find their initial application and about optimum ways to design such engines. It is shown that hydrogen-fueled reciprocal internal combustion engines offer important advantages with respect to thermal efficiency and exhaust emissions. Problems arising from preignition can suitably be avoided by restricting the fuel-air equivalence ratio to values below about 0.5. The direct cylinder injection appears to be a very attractive way to operate the engine, because it combines a wide range of possible power outputs with a high thermal efficiency and very low NO emissions at part loads.

  9. Near-surface alloys for hydrogen fuel cell applications

    DEFF Research Database (Denmark)

    Greeley, Jeffrey Philip; Mavrikakis, Manos

    2006-01-01

    of CO with relatively facile H-2 activation is nearly ideal for this application. We suggest that. as nanoscale materials synthesis techniques improve, it will become feasible to reproducibly prepare NSAs with highly specified surface structures, resulting in the design and manufacture of a wide variety...... facile H-2 activation. These NSAs could, potentially, facilitate highly selective hydrogenation reactions at low temperatures. In the present work, the suitability of NSAs for use as hydrogen fuel cell anodes has been evaluated: the combination of properties, possessed by selected NSAs, of weak binding...... of such materials for use in fuel cells and in an ever. increasing range of catalytic applications. Furthermore, we introduce a new concept for NSA-defect sites, which could be responsible for the promotional catalytic effects of a second metal added. even in minute quantities, to a host metal catalyst....

  10. The Design of a Renewable Hydrogen Fuel Infrastructure for London

    International Nuclear Information System (INIS)

    Parissis, O.; Bauen, A.

    2006-01-01

    The development of a least cost hydrogen infrastructure is key to the introduction of hydrogen fuel in road transport. This paper presents a generic framework for modelling the development of a renewable hydrogen infrastructure that can be applied to different cases and geographical regions. The model was designed by means of mixed integer linear programming and developed in MATLAB. It was applied to the case of London aiming to examine the possibilities of developing a renewable hydrogen infrastructure within a 50 years time horizon. The results presented here are preliminary results from a study looking at the least cost solutions to supplying hydrogen produced exclusively from renewable energy resources to large urban centres. (authors)

  11. Hydrogen fuel : well-to-pump pathways for 2050

    Energy Technology Data Exchange (ETDEWEB)

    Molburg, J. [Argonne National Lab., IL (United States); Mintz, M.; Folga, S.; Gillette, J.

    2002-07-01

    The authors discussed the topic of hydrogen fuels, and began the presentation by stating that the carbon intensity of world primary energy has been falling and hydrogen intensity has been rising. The declines in carbon can be explained by efficiency gains and fuel switches. There are several alternatives to gasoline fuel for vehicles, such as hydrogen, compressed natural gas, compressed natural gas/hydrogen. Emissions of greenhouse gases in the atmosphere represent a growing concern. The authors discussed four hydrogen pathways that have been modeled. They indicated that both natural gas pathways required additional natural gas transmission and storage. To better illustrate the hydrogen pathway, a conceptual representation of hydrogen pipeline loop supporting local hydrogen delivery was displayed. Some hydrogen distribution assumptions for centralized hydrogen production were examined. A cost modeling procedure was described, with the following topics: defining paths, determining tank-in fuel requirement, size pathway components, estimating component costs, and calculating pathway costs. The results indicated that the natural gas-based pathways were sensitive to feedstock cost, while coal and nuclear were not. Some of the conclusions that were arrived at were: (1) on a well-to-pump basis, with current technologies, the unit cost of hydrogen is expected to be 2 to 3 time that of gasoline, (2) the mpge of hydrogen-fueled vehicles must be more than double gasoline, and (3) hydrogen transport and production are the largest components of all pathways. For the future, the focus has to be on transition, including total and unit costs through study time frame, penetration of hydrogen blends, and niche markets. One must compare apples to apples, i e cost of infrastructure components over time, and learning curves. Pathways and scenarios must be re-examined, to include issues such as truck, rail marine market penetration; and hydrogen carrier pathways. Disruptive

  12. Project Profile: Hydrogen Fuel Cell Mobile Lighting Tower (HFCML)

    Science.gov (United States)

    McLaughlin, Russell

    2013-01-01

    NASA is committed to finding innovative solutions that improve the operational performance of ground support equipment while providing environment and cost benefits, as well. Through the Hydrogen Fuel Cell Mobile Lighting Tower (HFCML) project, NASA gained operational exposure to a novel application of high efficiency technologies. Traditionally, outdoor lighting and auxiliary power at security gates, launch viewing sites, fallback areas, outage support, and special events is provided by diesel generators with metal halide lights. Diesel generators inherently contribute to C02, NOx, particulate emissions, and are very noisy. In 2010, engineers from NASA's Technology Evaluation for Environmental Risk Mitigation Principal Center (TEERM) introduced KSC operations to a novel technology for outdoor lighting needs. Developed by a team led by Sandia National Laboratory (SNL), the technology pairs a 5kW hydrogen fuel cell with robust high efficiency plasma lights in a towable trailer. Increased efficiency, in both the fuel cell power source and lighting load, yields longer run times between fueling operations while providing greater auxiliary power. Because of the unit's quiet operation and no exhaust fumes, it is capable of being used indoors and in emergency situations, and meets the needs of all other operational roles for metal halide/diesel generators. The only discharge is some water and warm air. Environmental benefits include elimination of diesel particulate emissions and estimated 73% greenhouse gas emissions savings when the hydrogen source is natural gas (per GREET model). As the technology matures the costs could become competitive for the fuel cell units which are approximately 5 times diesel units. Initial operational . concerns included the hydrogen storage tanks and valves, lightning safety/grounding, and required operating and refueling procedures. TEERM facilitated technical information exchange (design drawings, technical standards, and operations

  13. Transit experience with hydrogen fueled hybrid electric buses

    International Nuclear Information System (INIS)

    Scott, P.B.; Mazaika, D.M.; Levin, J.; Edwards, T.

    2006-01-01

    Both AC Transit and SunLine Transit operate hybrid electric hydrogen fueled buses in their transit service. ACT presently operates three fuel cell buses in daily revenue service, and SunLine operates a fuel cell bus and a HHICE (Hybrid Hydrogen Internal Combustion Engine) bus. All these buses use similar electric drive train and electric accessories, although the detailed design differs notably between the fuel cell and the hybrid ICE buses. The fuel cell buses use a 120kW UTC fuel cell and a Van Hool Chassis, whereas the HHICE bus uses a turbocharged Ford engine which is capable of 140kW generator output in a New Flyer Chassis. The HHICE bus was the first in service, and has been subjected to both winter testing in Manitoba, Canada and summer testing in the Palm Springs, CA region. The winter testing included passenger sampling using questionnaires to ascertain passenger response. The fuel cell buses were introduced to service at the start of 2006. All five buses are in daily revenue service use. The paper will describe the buses and the experience of the transit properties in operating the buses. (author)

  14. Hydrogen fuel injection - the bridge to fuel cells

    International Nuclear Information System (INIS)

    Gilchrist, J.S.

    2004-01-01

    'Full text:' For over a century, industry has embraced a wide variety of applications for hydrogen. Since the mid-1970's, the focus of the bulk of hydrogen research has been in the area of fuel cells. Unfortunately, there is limited awareness of more immediate applications for hydrogen as a catalyst designed to improve the performance of existing hydro-carbon fuelled internal combustion engines. Canadian Hydrogen Energy Company manufactures a patented Hydrogen Fuel Injection System (HFI) that produces hydrogen and oxygen from distilled water and injects them, in measured amounts, into the air intake system on any heavy-duty diesel or gasoline application including trucks, buses, stationary generators, etc. In use on over 30 fleets, research is supported by over 40 million miles of field data. The hydrogen acts as a catalyst to promote more complete combustion, with remarkable results. Dramatically reduce emissions, particularly Carbon Monoxide and Particulate Matter. Increase horsepower and torque. Improved fuel efficiency (a minimum 10% improvement is guaranteed). Reduced oil degradation The HFI system offers the first large-scale application of the use of hydrogen and an excellent bridge to the fuel-cell technologies of the future. (author)

  15. Design of hydrogen fueling station for Vancouver BC

    International Nuclear Information System (INIS)

    Tura, A.; Dikeos, J.; St Germain, L.; Smolak, T.; Owen, T.; Hass, J.; Songprakorp, R.; Sodouri, P.; Maddaloni, J.

    2004-01-01

    'Full text:' A public hydrogen refueling station has been designed to service a minimum daily capacity of 50 light-duty hydrogen fuel cell vehicles, each requiring 3 kg of compressed gaseous hydrogen at 5000 psi. The station can accommodate a peak hourly fueling rate of 20 kg, or slightly less than 7 cars. The station is designed around liquid hydrogen, and energy efficient liquid compression. On-site storage with centralized production allows for great flexibility in the design and the simple fueling process results in fewer potential failure modes. High customer demand can easily be accommodated due to a four minute filling time, made possible by a low temperature hydrogen filling system. The overall well to wheel pathway of this fueling process generates up to 95% less CO2 and requires up to 42% less energy than gasoline. The proposed design requires a low capital investment, and uses components easily available from a proven supplier base. An economic analysis shows that the delivered hydrogen cost is between $0.11/mile and $0.18/mile, based on a ten year discounted cash flow analysis. This design was the grand prize winner in the NHA/DOE sponsored 2004 University Design Contest. (author)

  16. Design of a hydrogen fueling station for Vancouver, BC

    International Nuclear Information System (INIS)

    Dikeos, J.; Haas, J.; Maddaloni, J.; Owen, T.; Smolak, T.; Songprakorp, R.; Sodouri, P.; St Germain, L.; Tura, A.; Rowe, A.

    2004-01-01

    A public hydrogen refueling station has been designed to service a minimum daily capacity of 50 light-duty hydrogen fuel cell vehicles, each requiring 3 kg of compressed gaseous hydrogen at 5000 psi. A peak hourly fueling rate of 20 kg, or slightly less than 7 cars, can be accommodated. The station is designed around bulk liquid hydrogen storage, and energy efficient liquid compression. On-site storage with centralized production allows for great flexibility in the design and the simple fueling process results in fewer potential failure modes. High customer demand can easily be accommodated due to a four minute filling time, made possible by a low temperature hydrogen filling system. The overall well to wheel pathway of this fueling process generates up to 95% less CO 2 and requires up to 42% less energy than gasoline. The proposed design requires a low capital investment, and uses components easily available from a proven supplier base. An economic analysis shows that the delivered hydrogen cost is between $0.11/mile and $0.18/mile, based on a ten year discounted cash flow analysis. (author)

  17. Safety evaluation of a hydrogen fueled transit bus

    Energy Technology Data Exchange (ETDEWEB)

    Coutts, D.A.; Thomas, J.K.; Hovis, G.L.; Wu, T.T. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1997-12-31

    Hydrogen fueled vehicle demonstration projects must satisfy management and regulator safety expectations. This is often accomplished using hazard and safety analyses. Such an analysis has been completed to evaluate the safety of the H2Fuel bus to be operated in Augusta, Georgia. The evaluation methods and criteria used reflect the Department of Energy`s graded approach for qualifying and documenting nuclear and chemical facility safety. The work focused on the storage and distribution of hydrogen as the bus motor fuel with emphases on the technical and operational aspects of using metal hydride beds to store hydrogen. The safety evaluation demonstrated that the operation of the H2Fuel bus represents a moderate risk. This is the same risk level determined for operation of conventionally powered transit buses in the United States. By the same criteria, private passenger automobile travel in the United States is considered a high risk. The evaluation also identified several design and operational modifications that resulted in improved safety, operability, and reliability. The hazard assessment methodology used in this project has widespread applicability to other innovative operations and systems, and the techniques can serve as a template for other similar projects.

  18. Influence of the Ambient Temperature, to the Hydrogen Fuel Cell Functioning

    Directory of Open Access Journals (Sweden)

    POPOVICI Ovidiu

    2012-10-01

    Full Text Available The reversible fuel cell can be used to produce hydrogen. The hydrogen is further the chemical energy source to produce electrical energy using the fuel cell. The ambient temperature will influence theparameters of the hydrogen fuel cell.

  19. Influence of the Ambient Temperature, to the Hydrogen Fuel Cell Functioning

    OpenAIRE

    POPOVICI Ovidiu; HOBLE Dorel Anton

    2012-01-01

    The reversible fuel cell can be used to produce hydrogen. The hydrogen is further the chemical energy source to produce electrical energy using the fuel cell. The ambient temperature will influence theparameters of the hydrogen fuel cell.

  20. Successful catheter directed thrombolysis of IVC and renal vein occlusive thrombus.

    LENUS (Irish Health Repository)

    McCarthy, E

    2011-11-01

    Thrombus formation is a recognised complication of IVC filter placement, however IVC and bilateral renal vein occlusion secondary to thrombus is much less common. We present a case of infrahepatic caval and bilateral renal vein occlusion secondary to thrombosis of a suprarenal IVC filter. With progressive clinical deterioration and failure of conservative medical management the patient underwent successful mechanical disruption and catheter directed thrombolysis.

  1. Direct-injection strategies for a hydrogen-fueled engine : an optical and numerical investigation

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, S.; Salazar, V. [Sandia National Labs, Albuquerque, NM (United States); Scarcelli, R.; Wallner, T. [Argonne National Lab, Argonne, IL (United States)

    2009-07-01

    Vehicles with hydrogen-fueled engines are competitive with systems based on fuel cells. There is a lack of fundamental knowledge about in-cylinder processes in hydrogen direct injection engines. This presentation discussed a study that used a variety of injector configurations to establish a broad database. A light-load conditions that can profit from stratification was investigated. Several results were presented, including the 5-hole nozzle produced an asymmetric jet pattern which may be good for late injection. Very lean regions in the wake of the transient jets were found to be similar to those found in diesel injection. The 13-hole nozzle demonstrated complete jet collapse, consistent with Schlieren imaging by Petersen. Stratification made efficiency sensitive to the targeting of the single-hole injector. Computational fluid dynamics with a commercially available code aimed to improve the process of design optimization. The simulation predicted less fuel dispersion than was experimentally measured. Details of the fuel penetration were captured. It was concluded that for the single-hole nozzle, the pre-spark fuel distribution is consistent with results from the fired engine. tabs., figs.

  2. A marked proportional rise in IVC aldosterone following cosyntropin administration during AVS is a signal to the presence of adrenal hyperplasia in primary aldosteronism.

    Science.gov (United States)

    Kline, G A; Pasieka, J L; Harvey, A; So, B; Dias, V C

    2014-05-01

    We hypothesized aldosteronoma responsiveness to cosyntropin may be a characterizing feature that could be determined in addition to standard adrenal vein sampling (AVS) data. We reviewed an AVS database from June 2005 to October 2011 including 65 patients with confirmed primary aldosteronism (PA) who underwent AVS and, if applicable, unilateral adrenalectomy. Patients were divided into confirmed lateralized and non-lateralized groups and subgrouped by histology. Plasma aldosterone in inferior vena cava (IVC) pre- and post-cosyntropin infusion during AVS was measured. Peak aldosterone and proportional change was compared between groups. Baseline and peak IVC aldosterone was higher in lateralized patients but incremental aldosterone rise was much greater in subjects with bilateral hyperplasia. From receiver operator characteristics (ROC) analysis, the optimized diagnostic cut point of peak IVC aldosterone of >649 pmol l(-1) would have a sensitivity of 94% for surgical disease although specificity of just 59%. A 250% increase in IVC aldosterone following cosyntropin would be specific enough to exclude 87% of surgical/lateralized disease. These diagnostic capabilities are similar to other results with non-AVS tests performed for diagnosis of lateralization. Although not specific enough to replace standard AVS interpretation, a marked IVC aldosterone increase after cosyntropin during AVS is a useful additional test to diagnose non-lateralizing forms of PA. Such a calculation requires no additional expense or tests.

  3. Transit experience with hydrogen fueled hybrid electric buses

    Energy Technology Data Exchange (ETDEWEB)

    Scott, P.B.; Mazaika, D.M. [ISE Corp., Poway, CA (United States)

    2006-07-01

    Mass transit buses are ideal candidates for hydrogen implementation due to their capability of carrying 30 to 60 kg of hydrogen. ISE Corporation is a supplier of hydrogen fueled buses, including the first hybrid electric fuel cell bus which was commercialized in 2002, the hybrid electric fuel cell bus, and the hybrid hydrogen internal combustion engine (HHICE) bus which was commercialized in 2004. The configuration of a HHICE bus was illustrated with reference to its engine, control system, energy storage, generator, drive motor, inverter and accessories. Although these vehicles are expensive, the cost is amortized over a large base of hours used and passengers carried. The buses are operated primarily in urban areas where quiet and clean operation is needed the most. ISE has established a joint venture with Thor industries to develop a series of fuel cell buses equipped with a 60 kW PEM fuel cell. A schematic illustrating the energy flow in HHICE bus was also presented. It was shown that regenerative braking recovers the energy of motion. When using regenerative braking, most of the braking energy is saved in the battery. ISE drive systems convert 30 per cent or more of the bus energy to electrical energy to be used in later acceleration. Reduced fuel consumption also reduces the vehicle emissions. Testing of HHICE buses in both summer and winter operating conditions have shown that the range needs to be improved along with engine component reliability and durability. Fuel supply is also a major issue. A comparison with a fuel cell hybrid system was also presented. In the United States, more than 100,000 miles have been logged for the use of hydrogen hybrid buses, fuel cell buses and HHICE buses. The HHICE bus offers low capital cost, familiar technologies, but some NOx. CAT absorber technology offers the possibility of near zero emission capability. The fuel cell bus was found to be more fuel efficient, and can travel nearly twice as far per unit energy as

  4. Predicting inferior vena cava (IVC) filter retrievability using positional parameters: A comparative study of various filter types.

    Science.gov (United States)

    Gotra, A; Doucet, C; Delli Fraine, P; Bessissow, A; Dey, C; Gallix, B; Boucher, L-M; Valenti, D

    2018-05-14

    To compare changes in inferior vena cava (IVC) filter positional parameters from insertion to removal and examine how they affect retrievability amongst various filter types. A total of 447 patients (260 men, 187 women) with a mean age of 55 years (range: 13-91 years) who underwent IVC filter retrieval between 2007-2014 were retrospectively included. Post-insertion and pre-retrieval angiographic studies were assessed for filter tilt, migration, strut wall penetration and retrieval outcomes. ANCOVA and multiple logistic regression models were used to analyze factors affecting retrieval success. Pairwise comparisons between filter types were performed. Of 488 IVC filter retrieval attempts, 94.1% were ultimately successful. The ALN filter had the highest mean absolute value of tilt (5.6 degrees), the Optease filter demonstrated the largest mean migration (-8.0mm) and the Bard G2 filter showed highest mean penetration (5.2mm). Dwell time of 0-90 days (OR, 11.1; P=0.01) or 90-180 days (OR, 2.6; P=0.02), net tilt of 10-15 degrees (OR 8.9; P=0.05), caudal migration of -10 to 0mm (OR, 3.46; P=0.03) and penetration less than 3mm (OR, 2.6; P=0.01) were positive predictors of successful retrievability. Higher odds of successful retrieval were obtained for the Bard G2X, Bard G2 and Cook Celect when compared to the ALN and Cordis Optease filters. Shorter dwell time, lower mean tilt, caudal migration and less caval wall penetration are positive predictors of successful IVC filter retrieval. Copyright © 2018 Société française de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  5. Assessment of hydrogen fuel cell applications using fuzzy multiple-criteria decision making method

    International Nuclear Information System (INIS)

    Chang, Pao-Long; Hsu, Chiung-Wen; Lin, Chiu-Yue

    2012-01-01

    Highlights: ► This study uses the fuzzy MCDM method to assess hydrogen fuel cell applications. ► We evaluate seven different hydrogen fuel cell applications based on 14 criteria. ► Results show that fuel cell backup power systems should be chosen for development in Taiwan. -- Abstract: Assessment is an essential process in framing government policy. It is critical to select the appropriate targets to meet the needs of national development. This study aimed to develop an assessment model for evaluating hydrogen fuel cell applications and thus provide a screening tool for decision makers. This model operates by selecting evaluation criteria, determining criteria weights, and assessing the performance of hydrogen fuel cell applications for each criterion. The fuzzy multiple-criteria decision making method was used to select the criteria and the preferred hydrogen fuel cell products based on information collected from a group of experts. Survey questionnaires were distributed to collect opinions from experts in different fields. After the survey, the criteria weights and a ranking of alternatives were obtained. The study first defined the evaluation criteria in terms of the stakeholders, so that comprehensive influence criteria could be identified. These criteria were then classified as environmental, technological, economic, or social to indicate the purpose of each criterion in the assessment process. The selected criteria included 14 indicators, such as energy efficiency and CO 2 emissions, as well as seven hydrogen fuel cell applications, such as forklifts and backup power systems. The results show that fuel cell backup power systems rank the highest, followed by household fuel cell electric-heat composite systems. The model provides a screening tool for decision makers to select hydrogen-related applications.

  6. Temperature measurements in the TORMAC IV-c plasma

    International Nuclear Information System (INIS)

    Greenwald, M.

    1978-09-01

    This thesis is divided into four main parts. The first is an introduction to the Tormac concept and a brief summary of the theoretical problems involved. The second part describes the experimental work with little detail. Both the construction and diagnostics are summarized. The third section is broken into two parts, a summary of the data taken on TORMAC IV-c and an explanation and discussion of the data. Finally, a number of lengthy appendices are included. These detail the construction and operation of the device and describe the principles and practice of the diagnostics employed

  7. Temperature measurements in the TORMAC IV-c plasma

    Energy Technology Data Exchange (ETDEWEB)

    Greenwald, M.

    1978-09-01

    This thesis is divided into four main parts. The first is an introduction to the Tormac concept and a brief summary of the theoretical problems involved. The second part describes the experimental work with little detail. Both the construction and diagnostics are summarized. The third section is broken into two parts, a summary of the data taken on TORMAC IV-c and an explanation and discussion of the data. Finally, a number of lengthy appendices are included. These detail the construction and operation of the device and describe the principles and practice of the diagnostics employed.

  8. HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER

    Energy Technology Data Exchange (ETDEWEB)

    BROWN,LC; BESENBRUCH,GE; LENTSCH,RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

    2003-06-01

    OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from

  9. Percutaneous sharp recanalization of a membranous IVC occlusion with an occlusion balloon as a needle target

    Directory of Open Access Journals (Sweden)

    Michael D. Rivers-Bowerman, MD, MSc, FRCPC

    2017-09-01

    Full Text Available A 50-year-old male with right upper quadrant symptoms and hepatic dysfunction was found to have multiple dilated hepatic veins (HVs with intrahepatic collateralization and membranous occlusion of the intrahepatic inferior vena cava (IVC consistent with primary Budd–Chiari syndrome. Venacavograms depicted drainage of the intrahepatic collaterals through a left-sided HV entering the IVC above the level of the occlusion. Sharp recanalization of the membranous IVC occlusion was performed with an occlusion balloon as a needle target under echocardiographic monitoring followed by balloon angioplasty with restoration of IVC patency. Clinical, laboratory, and venographic procedural success has been demonstrated to 9 months with minimal residual stenosis.

  10. Conclusions and recommendations. [for problems in energy situation, air transportation, and hydrogen fuel

    Science.gov (United States)

    1973-01-01

    Conclusions and recommendations are presented for an analysis of the total energy situation; the effect of the energy problem on air transportation; and hydrogen fuel for aircraft. Properties and production costs of fuels, future prediction for energy and transportation, and economic aspects of hydrogen production are appended.

  11. A Barrier Options Approach to Modeling Project Failure : The Case of Hydrogen Fuel Infrastructure

    NARCIS (Netherlands)

    Engelen, P.J.; Kool, C.J.M.; Li, Y.

    2016-01-01

    Hydrogen fuel cell vehicles have the potential to contribute to a sustainable transport system with zero tailpipe emissions. This requires the construction of a network of fuel stations, a long-term, expensive and highly uncertain investment. We contribute to the literature by including a knock-out

  12. Public perception related to a hydrogen hybrid internal combustion engine transit bus demonstration and hydrogen fuel

    International Nuclear Information System (INIS)

    Hickson, Allister; Phillips, Al; Morales, Gene

    2007-01-01

    Hydrogen has been widely considered as a potentially viable alternative to fossil fuels for use in transportation. In addition to price competitiveness with fossil fuels, a key to its adoption will be public perceptions of hydrogen technologies and hydrogen fuel. This paper examines public perceptions of riders of a hydrogen hybrid internal combustion engine bus and hydrogen as a fuel source

  13. Creation of an iOS and Android Mobile Application for Inferior Vena Cava (IVC) Filters: A Powerful Tool to Optimize Care of Patients with IVC Filters.

    Science.gov (United States)

    Deso, Steven E; Idakoji, Ibrahim A; Muelly, Michael C; Kuo, William T

    2016-06-01

    Owing to a myriad of inferior vena cava (IVC) filter types and their potential complications, rapid and correct identification may be challenging when encountered on routine imaging. The authors aimed to develop an interactive mobile application that allows recognition of all IVC filters and related complications, to optimize the care of patients with indwelling IVC filters. The FDA Premarket Notification Database was queried from 1980 to 2014 to identify all IVC filter types in the United States. An electronic search was then performed on MEDLINE and the FDA MAUDE database to identify all reported complications associated with each device. High-resolution photos were taken of each filter type and corresponding computed tomographic and fluoroscopic images were obtained from an institutional review board-approved IVC filter registry. A wireframe and storyboard were created, and software was developed using HTML5/CSS compliant code. The software was deployed using PhoneGap (Adobe, San Jose, CA), and the prototype was tested and refined. Twenty-three IVC filter types were identified for inclusion. Safety data from FDA MAUDE and 72 relevant peer-reviewed studies were acquired, and complication rates for each filter type were highlighted in the application. Digital photos, fluoroscopic images, and CT DICOM files were seamlessly incorporated. All data were succinctly organized electronically, and the software was successfully deployed into Android (Google, Mountain View, CA) and iOS (Apple, Cupertino, CA) platforms. A powerful electronic mobile application was successfully created to allow rapid identification of all IVC filter types and related complications. This application may be used to optimize the care of patients with IVC filters.

  14. Prophylactic IVC Filter Placement during Endovascular Treatment of Deep Venous Thrombosis of the Lower Extremities

    International Nuclear Information System (INIS)

    Roh, Byung Suk; Cho, Han Il; Lee, Yeum Sik; Bang, Dong Ho; Park, Seong Hoon; Lee, Young Hwan

    2009-01-01

    To evaluate the efficacy of an IVC filter implantation in the prevent of a pulmonary embolism (PE) during endovascular treatment for a deep venous thrombosis (DVT) of the lower extremities. We implanted IVC filters in 43 patients (22 females, 21 males, average age: 63 years) with DVT and who had undergone treatments including thrombolysis, aspiration and mechanical thrombectomy, as well as stent placement. We evaluated the incidence of PE by capturing the thrombus within the IVC filters, as well as the amount of captured thrombus. New developing PE or aggravating of PE in patients with existing PE was avoided in all patients. No thrombus was evident in the IVC filter of 19 (44%) of the patients, whereas any thrombus was captured in 24 (56%) of the patients. Small amounts of thrombus were captured in 10 patients, whereas large amounts of thrombus were captured in 14 patents within the IVC filter. We performed a retrieval of the IVC filters in 17 patients within an average period of 15.3 days (range 6-45 days). The captured incidence of migrated thrombus in the IVC filters was high in 56% of cases. As a result, PE was effectively prevented by IVC filters during the interventional treatment of DVT in the lower extremities

  15. Prophylactic IVC Filter Placement during Endovascular Treatment of Deep Venous Thrombosis of the Lower Extremities

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Byung Suk; Cho, Han Il; Lee, Yeum Sik; Bang, Dong Ho; Park, Seong Hoon; Lee, Young Hwan [Wonkwang University Hospital, Iksan (Korea, Republic of)

    2009-09-15

    To evaluate the efficacy of an IVC filter implantation in the prevent of a pulmonary embolism (PE) during endovascular treatment for a deep venous thrombosis (DVT) of the lower extremities. We implanted IVC filters in 43 patients (22 females, 21 males, average age: 63 years) with DVT and who had undergone treatments including thrombolysis, aspiration and mechanical thrombectomy, as well as stent placement. We evaluated the incidence of PE by capturing the thrombus within the IVC filters, as well as the amount of captured thrombus. New developing PE or aggravating of PE in patients with existing PE was avoided in all patients. No thrombus was evident in the IVC filter of 19 (44%) of the patients, whereas any thrombus was captured in 24 (56%) of the patients. Small amounts of thrombus were captured in 10 patients, whereas large amounts of thrombus were captured in 14 patents within the IVC filter. We performed a retrieval of the IVC filters in 17 patients within an average period of 15.3 days (range 6-45 days). The captured incidence of migrated thrombus in the IVC filters was high in 56% of cases. As a result, PE was effectively prevented by IVC filters during the interventional treatment of DVT in the lower extremities.

  16. Exergy analysis of components of integrated wind energy / hydrogen / fuel cell

    International Nuclear Information System (INIS)

    Hernandez Galvez, G.; Pathiyamattom, J.S.; Sanchez Gamboa, S.

    2009-01-01

    Exergy analysis is made of three components of an integrated wind energy to hydrogen fuel cell: wind turbine, fuel cell (PEMFC) and electrolyzer (PEM). The methodology used to assess how affect the second law efficiency of the electrolyzer and the FC parameters as temperature and operating pressure and membrane thickness. It develop methods to evaluate the influence of changes in the air density and height of the tower on the second law efficiency of the turbine. This work represents a starting point for developing the global availability analysis of an integrated wind / hydrogen / fuel cells, which can be used as a tool to achieve the optimum design of the same. The use of this system contribute to protect the environment

  17. PERFORMANCE EVALUATION OF EXTERNAL MIXTURE FORMATION STRATEGY IN HYDROGEN-FUELED ENGINE

    OpenAIRE

    Mohammed Kamil; M. M. Rahman; Rosli A. Bakar

    2011-01-01

    Mohammed Kamil1, M. M. Rahman2 and Rosli A. Bakar2Hydrogen induction strategy in an internal combustion engine plays a vital role in increasing the power density and prohibiting combustion anomalies. This paper inspects the performance characteristics of cylinder hydrogen-fueled engine with port injection feeding strategy. To that end, a one-dimensional gas dynamic model has been built to represent the flow and heat transfer in the components of the engine. The governing equations are introdu...

  18. Numerical Study on the Performance Characteristics of Hydrogen Fueled Port Injection Internal Combustion Engine

    OpenAIRE

    Rosli A. Bakar; Mohammed K. Mohammed; M. M. Rahman

    2009-01-01

    This study was focused on the engine performance of single cylinder hydrogen fueled port injection internal combustion engine. GT-Power was utilized to develop the model for port injection engine. One dimensional gas dynamics was represented the flow and heat transfer in the components of the engine model. The governing equations were introduced first, followed by the performance parameters and model description. Air-fuel ratio was varied from stoichiometric limit to a lean limit and the rota...

  19. Safety issues in urban transit facilities for hydrogen-fueled buses

    International Nuclear Information System (INIS)

    Hay, R.H.; Ducharme, P.

    2004-01-01

    'Full text:' The Canadian Transportation Fuel Cell Alliance (CTFCA), created by the Canadian Government as part of its 2000 Climate Change Action Plan, has commissioned MARCON-DDM's Hydrogen Intervention Team (HIT) to provide a roadmap for urban transit systems that wish to move to hydrogen fuel cell-powered bus fleets. HIT is currently in the process of gathering information from hydrogen technology providers, bus manufacturers, fuelling system providers and urban transit systems in Canada, the US and Europe. In September, HIT will be in a position to provide a hands-on perspective of the introduction of fuel-cell buses in the Canadian environment. Part of the process of adding hydrogen-fueled busses to urban transit systems involves phasing in the new technology to minimize the economic cost. This involves substituting hydrogen buses into the normal bus procurement life cycle and maximizing the use of existing facilities for garaging, maintenance and fueling. Using a schematic outline of an urban transit system, this presentation will outline the safety issues specific to hydrogen in such systems, particularly for garaging, maintenance and fueling components. It will then outline how safety of these component is addressed in current and proposed codes, standards and recommended practices. Based on these requirements the impact of the introduction of hydrogen-fueled buses on each component of the transit system will be addressed in terms of the adaptations of current facilities and practices or the requirements for new facilities and practices. (author)

  20. Impact of experience on government policy toward acceptance of hydrogen fuel cell vehicles in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Min Jung [Department of Information and Industrial Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemoon-Gu, Seoul 120-749 (Korea, Republic of); Park, Heejun, E-mail: h.park@yonsei.ac.kr [Department of Information and Industrial Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemoon-Gu, Seoul 120-749 (Korea, Republic of)

    2011-06-15

    As the 'low carbon, green growth' agenda, which emphasized sustainable development through equilibrium between economic growth and environmental preservation, is propagated rapidly in Korea. Despite this progress, it is not uncommon for new products made through advanced technologies, such as hydrogen fuel cell vehicles, to face public skepticism preventing market penetration. Therefore, the factors impacting customer acceptance of hydrogen fuel cell vehicles have to be estimated. Furthermore, it is necessary to examine whether or not the policies related to these products can prevent public skepticism regarding them. This empirical study examining the relationship between personal experiences related to the policy and acceptance of the innovative products of hydrogen fuel cell vehicles shows that government involvement in technology targeting and promotions administered by the 'low carbon, green growth' agenda rarely stimulate potential customers' purchase intentions. Thus, technology targeting administered by the 'low carbon, green growth' agenda needs to be reconciled with customer responses to the future market. - Highlights: > Experience of the 'low carbon, green growth' policy affects perception of it. > Positive perception on the policy seldom arouses positive perception on HFCV performance. > Technology targeting by the policy rarely stimulates purchase intention of HFCV. > Desire to be regarded as a person with environment concern impacts purchase intentions.> Technology targeting by the policy needs to be reconciled with customer responses to it.

  1. Impact of experience on government policy toward acceptance of hydrogen fuel cell vehicles in Korea

    International Nuclear Information System (INIS)

    Kang, Min Jung; Park, Heejun

    2011-01-01

    As the 'low carbon, green growth' agenda, which emphasized sustainable development through equilibrium between economic growth and environmental preservation, is propagated rapidly in Korea. Despite this progress, it is not uncommon for new products made through advanced technologies, such as hydrogen fuel cell vehicles, to face public skepticism preventing market penetration. Therefore, the factors impacting customer acceptance of hydrogen fuel cell vehicles have to be estimated. Furthermore, it is necessary to examine whether or not the policies related to these products can prevent public skepticism regarding them. This empirical study examining the relationship between personal experiences related to the policy and acceptance of the innovative products of hydrogen fuel cell vehicles shows that government involvement in technology targeting and promotions administered by the 'low carbon, green growth' agenda rarely stimulate potential customers' purchase intentions. Thus, technology targeting administered by the 'low carbon, green growth' agenda needs to be reconciled with customer responses to the future market. - Highlights: → Experience of the 'low carbon, green growth' policy affects perception of it. → Positive perception on the policy seldom arouses positive perception on HFCV performance. → Technology targeting by the policy rarely stimulates purchase intention of HFCV. → Desire to be regarded as a person with environment concern impacts purchase intentions.→ Technology targeting by the policy needs to be reconciled with customer responses to it.

  2. Accuracy of computed tomography-intravenous cholangiography (CT-IVC) in detection of choledocholithiasis)

    International Nuclear Information System (INIS)

    Gibson, R.; Speer, A.G.; Collier, N.A.; Vincent, J.M.; Jardine, C.; Noack, K.

    2002-01-01

    Full text: The aim of the study was to determine the accuracy of computed tomography-intravenous cholangiography (CT-IVC) in the detection of choledocholithiasis, compared with endoscopic retrograde cholangiography (ERC). 65 patients undergoing ERC had CT-IVC within 24 hours prior to ERC. Helical CT-IVC was performed following intravenous infusion of 100ml Biliscopin (Schering, Berlin). 2mm beam collimation was used with axial reformats at 1.5mm intervals used for image interpretation. Patients with serum bilirubin levels>3 times normal were excluded. CT-IVC and ERC studies were interpreted independently, and studies were graded as positive, negative or indeterminate for the presence of ductal calculi. 65 patients had a median age of 56 years. Median serum bilirubin at the time of CT-IVC was 13 mmol/L (range 5-47). ERC was indeterminate in 3 patients (4.7%) and CT-IVC in 4 (6.3%). 23 patients had ductal calculi on ERC and CT-IVC was positive in 22 (sensitivity 96%). False positive rate for CT-IVC was 8.3% with positive and negative predictive values of 92% and 97% respectively. Stones' size range was 4-16mm. Of the 14 solitary stones, 10 were pound 5mm and 8 pound 4mm.The bilirubin level in the positive cases was within the normal range in 20, with a range of 7-37 mmol/L. CT-IVC is highly accurate for detection of ductal calculi, including single small calculi, in patients with a serum bilirubin of <3 times normal. Copyright (2002) Blackwell Science Pty Ltd

  3. British Society of Interventional Radiology (BSIR) Inferior Vena Cava (IVC) Filter Registry

    International Nuclear Information System (INIS)

    Uberoi, Raman; Tapping, Charles Ross; Chalmers, Nicholas; Allgar, Victoria

    2013-01-01

    Purpose: The British Society of Interventional Radiology (BSIR) Inferior Vena Cava (IVC) Filter Registry was produced to provide an audit of current United Kingdom (UK) practice regarding placement and retrieval of IVC filters to address concerns regarding their safety. Methods: The IVC filter registry is a web-based registry, launched by the BSIR on behalf of its membership in October 2007. This report is based on prospectively collected data from October 2007 to March 2011. This report contains analysis of data on 1,434 IVC filter placements and 400 attempted retrievals performed at 68 UK centers. Data collected included patient demographics, insertion and retrieval data, and patient follow-up. Results: IVC filter use in the majority of patients in the UK follows accepted CIRSE guidelines. Filter placement is usually a low-risk procedure, with a low major complication rate ( 9 weeks versus those with a shorter dwell time. New lower limb deep vein thrombosis (DVT) and/or IVC thrombosis was reported in 88 patients following filter placement, there was no significant difference of incidence between filter types. Conclusions: This registry report provides interventional radiologists and clinicians with an improved understanding of the technical aspects of IVC filter placement to help improve practice, and the potential consequences of IVC filter placement so that we are better able to advise patients. There is a significant learning curve associated with IVC filter insertion, and when a filter is placed with the intention of removal, procedures should be in place to avoid the patient being lost to follow-up

  4. British Society of Interventional Radiology (BSIR) Inferior Vena Cava (IVC) Filter Registry

    Energy Technology Data Exchange (ETDEWEB)

    Uberoi, Raman, E-mail: raman.Uberoi@orh.nhs.uk; Tapping, Charles Ross [Oxford University Hospitals, John Radcliffe Hospital, Department of Radiology (United Kingdom); Chalmers, Nicholas [Manchester Royal Infirmary, Department of Radiology (United Kingdom); Allgar, Victoria [University of York, Hull and York Medical School (United Kingdom)

    2013-12-15

    Purpose: The British Society of Interventional Radiology (BSIR) Inferior Vena Cava (IVC) Filter Registry was produced to provide an audit of current United Kingdom (UK) practice regarding placement and retrieval of IVC filters to address concerns regarding their safety. Methods: The IVC filter registry is a web-based registry, launched by the BSIR on behalf of its membership in October 2007. This report is based on prospectively collected data from October 2007 to March 2011. This report contains analysis of data on 1,434 IVC filter placements and 400 attempted retrievals performed at 68 UK centers. Data collected included patient demographics, insertion and retrieval data, and patient follow-up. Results: IVC filter use in the majority of patients in the UK follows accepted CIRSE guidelines. Filter placement is usually a low-risk procedure, with a low major complication rate (<0.5 %). Cook Gunther Tulip (560 filters: 39 %) and Celect (359 filters: 25 %) filters constituted the majority of IVC filters inserted, with Bard G2, Recovery filters, Cordis Trapease, and OptEase constituting most of the remainder (445 filters: 31 %). More than 96 % of IVC filters deployed as intended. Operator inexperience (<25 procedure) was significantly associated with complications (p < 0.001). Of the IVC filters initially intended for temporary placement, retrieval was attempted in 78 %. Of these retrieval was technically successful in 83 %. Successful retrieval was significantly reduced for implants left in situ for >9 weeks versus those with a shorter dwell time. New lower limb deep vein thrombosis (DVT) and/or IVC thrombosis was reported in 88 patients following filter placement, there was no significant difference of incidence between filter types. Conclusions: This registry report provides interventional radiologists and clinicians with an improved understanding of the technical aspects of IVC filter placement to help improve practice, and the potential consequences of IVC filter

  5. Relationship between serum IV-C, β2-m levels and diabetic nephropathy

    International Nuclear Information System (INIS)

    Liu Lu; Zhang Mukun

    2005-01-01

    Objective: To investigate the relationship between the serum type IV collagen (IV-C), β 2 -micro globulin (β 2 -m) levels and diabetic nephropathy. Methods: Serum IV-C, β 2 -m levels were measured with RIA in 30 controls and 86 patients with type 2 diabetics mellitus (35 with diabetic nephropathy and 51 without nephropathy). Results: the serum levels of IV-C and β 2 -m in diabetic patients with nephropathy were significantly higher than those in controls (P 0.05). Conclusion: Serum IV-C and β 2 -m levels increased gradually as the diabetic nephropathy got more severe. They could be a sensitive marker for early diagnosis of development of diabetic nephropathy. (authors)

  6. IVC filter limb penetration of the caval wall during retroperitoneal surgery/lymph node dissection.

    LENUS (Irish Health Repository)

    Goh, Gerard S

    2012-12-01

    Optional inferior vena cava (IVC) filters are being increasingly used for protection against pulmonary embolism in patients with deep vein thrombosis where anticoagulation is contraindicated. We describe two cases during retroperitoneal surgery where the IVC filters were found to have perforated the cava wall and were subsequently removed intra-operatively. Cava wall penetration by filter limbs poses a significant danger during retroperitoneal lymph node dissection and filters should be removed preoperatively.

  7. A polymer electrolyte fuel cell stack for stationary power generation from hydrogen fuel

    Energy Technology Data Exchange (ETDEWEB)

    Gottesfeld, S. [Los Alamos National Lab., NM (United States)

    1995-09-01

    The fuel cell is the most efficient device for the conversion of hydrogen fuel to electric power. As such, the fuel cell represents a key element in efforts to demonstrate and implement hydrogen fuel utilization for electric power generation. The low temperature, polymer electrolyte membrane fuel cell (PEMFC) has recently been identified as an attractive option for stationary power generation, based on the relatively simple and benign materials employed, the zero-emission character of the device, and the expected high power density, high reliability and low cost. However, a PEMFC stack fueled by hydrogen with the combined properties of low cost, high performance and high reliability has not yet been demonstrated. Demonstration of such a stack will remove a significant barrier to implementation of this advanced technology for electric power generation from hydrogen. Work done in the past at LANL on the development of components and materials, particularly on advanced membrane/electrode assemblies (MEAs), has contributed significantly to the capability to demonstrate in the foreseeable future a PEMFC stack with the combined characteristics described above. A joint effort between LANL and an industrial stack manufacturer will result in the demonstration of such a fuel cell stack for stationary power generation. The stack could operate on hydrogen fuel derived from either natural gas or from renewable sources. The technical plan includes collaboration with a stack manufacturer (CRADA). It stresses the special requirements from a PEMFC in stationary power generation, particularly maximization of the energy conversion efficiency, extension of useful life to the 10 hours time scale and tolerance to impurities from the reforming of natural gas.

  8. Development of Sensors and Sensing Technology for Hydrogen Fuel Cell Vehicle Applications

    Energy Technology Data Exchange (ETDEWEB)

    Brosha, E L; Sekhar, P K; Mukundan, R; Williamson, T; Garzon, F H; Woo, L Y; Glass, R R

    2010-01-06

    One related area of hydrogen fuel cell vehicle (FCV) development that cannot be overlooked is the anticipated requirement for new sensors for both the monitoring and control of the fuel cell's systems and for those devices that will be required for safety. Present day automobiles have dozens of sensors on-board including those for IC engine management/control, sensors for state-of-health monitoring/control of emissions systems, sensors for control of active safety systems, sensors for triggering passive safety systems, and sensors for more mundane tasks such as fluids level monitoring to name the more obvious. The number of sensors continues to grow every few years as a result of safety mandates but also in response to consumer demands for new conveniences and safety features. Some of these devices (e.g. yaw sensors for dynamic stability control systems or tire presure warning RF-based devices) may be used on fuel cell vehicles without any modification. However the use of hydrogen as a fuel will dictate the development of completely new technologies for such requirements as the detection of hydrogen leaks, sensors and systems to continuously monitor hydrogen fuel purity and protect the fuel cell stack from poisoning, and for the important, yet often taken for granted, tasks such as determining the state of charge of the hydrogen fuel storage and delivery system. Two such sensors that rely on different transduction mechanisms will be highlighted in this presentation. The first is an electrochemical device for monitoring hydrogen levels in air. The other technology covered in this work, is an acoustic-based approach to determine the state of charge of a hydride storage system.

  9. Experimental-demonstrative system for energy conversion using hydrogen fuel cell - preliminary results

    International Nuclear Information System (INIS)

    Stoenescu, D.; Stefanescu, I.; Patularu, I.; Culcer, M.; Lazar, R.E.; Carcadea, E.; Mirica, D. . E-mail address of corresponding author: daniela@icsi.ro; Stoenescu, D.)

    2005-01-01

    It is well known that hydrogen is the most promising solution of future energy, both for long and medium term strategies. Hydrogen can be produced using many primary sources (natural gas, methane, biomass, etc.), it can be burned or chemically react having a high yield of energy conversion, being a non-polluted fuel. This paper presents the preliminary results obtained by ICSI Rm. Valcea in an experimental-demonstrative conversion energy system made by a sequence of hydrogen purification units and a CO removing reactors until a CO level lower than 10ppm, that finally feeds a hydrogen fuel stack. (author)

  10. Project Termination Report. Title IV-C Classroom Management Project. ESEA Title IV-C, August 29, 1981 - September 30, 1982.

    Science.gov (United States)

    Halasa, Ofelia; Theus, Frank

    This report provides a summary description of the Title IV-C Classroom Management Project conducted in the Cleveland (Ohio) Public Schools. The purpose of this project was to develop and pilot test a resource handbook designed to improve elementary and secondary school teachers' ability to organize and manage their classrooms. The development of…

  11. A dynamic simulation tool for the battery-hybrid hydrogen fuel cell vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Moore, R.M. [Hawaii Natural Energy Institute, University of Hawaii, Manoa (United States); Ramaswamy, S.; Cunningham, J.M. [California Univ., Berkeley, CA (United States); Hauer, K.H. [xcellvision, Major-Hirst-Strasse 11, 38422 Wolfsburg (Germany)

    2006-10-15

    This paper describes a dynamic fuel cell vehicle simulation tool for the battery-hybrid direct-hydrogen fuel cell vehicle. The emphasis is on simulation of the hybridized hydrogen fuel cell system within an existing fuel cell vehicle simulation tool. The discussion is focused on the simulation of the sub-systems that are unique to the hybridized direct-hydrogen vehicle, and builds on a previous paper that described a simulation tool for the load-following direct-hydrogen vehicle. The configuration of the general fuel cell vehicle simulation tool has been previously presented in detail, and is only briefly reviewed in the introduction to this paper. Strictly speaking, the results provided in this paper only serve as an example that is valid for the specific fuel cell vehicle design configuration analyzed. Different design choices may lead to different results, depending strongly on the parameters used and choices taken during the detailed design process required for this highly non-linear and n-dimensional system. The primary purpose of this paper is not to provide a dynamic simulation tool that is the ''final word'' for the ''optimal'' hybrid fuel cell vehicle design. The primary purpose is to provide an explanation of a simulation method for analyzing the energetic aspects of a hybrid fuel cell vehicle. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  12. PERFORMANCE EVALUATION OF EXTERNAL MIXTURE FORMATION STRATEGY IN HYDROGEN-FUELED ENGINE

    Directory of Open Access Journals (Sweden)

    Mohammed Kamil

    2011-12-01

    Full Text Available Mohammed Kamil1, M. M. Rahman2 and Rosli A. Bakar2Hydrogen induction strategy in an internal combustion engine plays a vital role in increasing the power density and prohibiting combustion anomalies. This paper inspects the performance characteristics of cylinder hydrogen-fueled engine with port injection feeding strategy. To that end, a one-dimensional gas dynamic model has been built to represent the flow and heat transfer in the components of the engine. The governing equations are introduced followed by the performance parameters and model description. Air-fuel ratio was varied from a stoichiometric limit to a lean limit. The rotational speed of the engine was also changed from 1000 to 4500 RPM. The injector location was fixed in the mid-point of the intake port. The general behavior of the hydrogen engine was similar to that of a gasoline engine, apart from a reduction in the power density, which was due to a decrease in the volumetric efficiency. This emphasizes the ability of retrofitting traditional engines for hydrogen fuel with minor modifications. The decrease in the volumetric efficiency needs to be rectified.

  13. Evaluation of AECL catalysts for hydrogen fuel-cell applications. Paper no. IGEC-1-073

    International Nuclear Information System (INIS)

    Li, J.; Suppiah, S.; Li, H.; Kutchcoskie, K.J.; Strikwerda, S.

    2005-01-01

    AECL has been engaged in the promotion of the nuclear-hydrogen economy, which envisions that hydrogen fuel cells will generate power using hydrogen as fuel produced by nuclear energy. Since AECL's catalysts developed for the production, upgrading and detritiation of heavy water are very similar to commercial fuel-cell catalysts, a program was initiated to evaluate AECL catalysts for fuel-cell applications. As a first step in this effort, a half-cell test facility was set up to characterize the performance of catalysts for hydrogen fuel cells. This paper outlines the results obtained from cathodic reduction of oxygen in a 0.5 M sulphuric acid solution on a rotating disc electrode at 65 o C. The performance of the catalysts was characterized using standard electrochemical methods including cyclic voltammetry, Voltammogram/Tafel plots and short-term stability plots. Several monometallic Pt and Pt-based bimetallic catalysts were tested and compared with a commercially available catalyst for fuel-cell applications. AECL's monometallic Pt catalysts showed comparable or better activities than commercial catalysts with similar Pt loading. An AECL Pt-based bimetallic catalyst has shown superior performance to a monometallic Pt catalyst with similar Pt loading. Evaluation of various catalyst formulations is ongoing on the half-cell facility at AECL. Further investigation of promising catalysts identified from half-cell test is also being carried out in single fuel cell on test stations under normal fuel-cell operating conditions. (author)

  14. Hydrogen Fuel System Design Trades for High-Altitude Long-Endurance Remotely- Operated Aircraft

    Science.gov (United States)

    Millis, Marc G.; Tornabene, Robert T.; Jurns, John M.; Guynn, Mark D.; Tomsik, Thomas M.; VanOverbeke, Thomas J.

    2009-01-01

    Preliminary design trades are presented for liquid hydrogen fuel systems for remotely-operated, high-altitude aircraft that accommodate three different propulsion options: internal combustion engines, and electric motors powered by either polymer electrolyte membrane fuel cells or solid oxide fuel cells. Mission goal is sustained cruise at 60,000 ft altitude, with duration-aloft a key parameter. The subject aircraft specifies an engine power of 143 to 148 hp, gross liftoff weight of 9270 to 9450 lb, payload of 440 lb, and a hydrogen fuel capacity of 2650 to 2755 lb stored in two spherical tanks (8.5 ft inside diameter), each with a dry mass goal of 316 lb. Hydrogen schematics for all three propulsion options are provided. Each employs vacuum-jacketed tanks with multilayer insulation, augmented with a helium pressurant system, and using electric motor driven hydrogen pumps. The most significant schematic differences involve the heat exchangers and hydrogen reclamation equipment. Heat balances indicate that mission durations of 10 to 16 days appear achievable. The dry mass for the hydrogen system is estimated to be 1900 lb, including 645 lb for each tank. This tank mass is roughly twice that of the advanced tanks assumed in the initial conceptual vehicle. Control strategies are not addressed, nor are procedures for filling and draining the tanks.

  15. Nitrogen-doped fullerene as a potential catalyst for hydrogen fuel cells.

    Science.gov (United States)

    Gao, Feng; Zhao, Guang-Lin; Yang, Shizhong; Spivey, James J

    2013-03-06

    We examine the possibility of nitrogen-doped C60 fullerene (N-C60) as a cathode catalyst for hydrogen fuel cells. We use first-principles spin-polarized density functional theory calculations to simulate the electrocatalytic reactions on N-C60. The first-principles results show that an O2 molecule can be adsorbed and partially reduced on the N-C complex sites (Pauling sites) of N-C60 without any activation barrier. Through a direct pathway, the partially reduced O2 can further react with H(+) and additional electrons and complete the water formation reaction (WFR) with no activation energy barrier. In the indirect pathway, reduced O2 reacts with H(+) and additional electrons to form H2O molecules through a transition state (TS) with a small activation barrier (0.22-0.37 eV). From an intermediate state to a TS, H(+) can obtain a kinetic energy of ∼0.95-3.68 eV, due to the Coulomb electric interaction, and easily overcome the activation energy barrier during the WFR. The full catalytic reaction cycles can be completed energetically, and N-C60 fullerene recovers to its original structure for the next catalytic reaction cycle. N-C60 fullerene is a potential cathode catalyst for hydrogen fuel cells.

  16. A comparison of hydrogen-fueled fuel cells and combustion engines for electric utility applications

    International Nuclear Information System (INIS)

    Schoenung, S.M.

    2000-01-01

    Hydrogen-fueled systems have been proposed for a number of stationary electric generation applications including remote power generation, load management, distribution system peak shaving, and reliability or power quality enhancement. Hydrogen fueling permits clean, low pollution operation. This is particularly true for systems that use hydrogen produced from electrolysis, rather than the reforming of hydrocarbon fuels. Both fuel cells and combustion engines are suitable technologies for using hydrogen in many electric utility applications. This paper presents results from several studies performed for the U.S. Department of Energy Hydrogen Program. A comparison between the two technologies shows that, whereas fuel cells are somewhat more energy efficient, combustion engine technology is less expensive. In this paper, a comparison of the two technologies is presented, with an emphasis on distributed power and power quality applications. The special case of a combined distributed generation I hydrogen refueling station is also addressed. The comparison is made on the basis of system costs and benefits, but also includes a comparison of technology status: power ratings and response time. A discussion of pollutant emissions and pollutant control strategies is included. The results show those electric utility applications for which each technology is best suited. (author)

  17. Accuracy of computed tomographic intravenous cholangiography (CT-IVC) with iotroxate in the detection of choledocholithiasis

    International Nuclear Information System (INIS)

    Gibson, Robert N.; Vincent, Janette M.; Speer, Tony; Noack, Keith; Collier, Neil A.

    2005-01-01

    To determine the accuracy of computed tomographic intravenous cholangiography (CT-IVC) for detection of choledocholithiasis. Sixty-five patients undergoing endoscopic retrograde cholangiography (ERC) underwent CT-IVC prior to ERC, using a single detector helical CT following intravenous infusion of 100 ml iotroxate. Patients with bilirubin levels >3 times normal were excluded. ERC was indeterminate in three patients (4.7%) and CT-IVC in four (6.3%). Twenty-three patients had ductal calculi at ERC, and CT-IVC was positive in 22, with two false positives and one false negative: sensitivity 95.6%, specificity 94.3%. Stones were multiple in nine and solitary in 14. Of the 14 solitary stones, ten were ≤5 mm and eight were ≤4 mm. The bilirubin level in positive cases was within normal in 20. Maximum intensity projection (MIP) reformats showed stones in only 27% of cases and surface rendered (SR) reformats in none. CT-IVC is highly accurate for detection of ductal calculi, including single small calculi, with a normal or near normal serum bilirubin. Axial images should be used for interpretation rather than MIP or SR reformats. (orig.)

  18. An experimental and computational study of the inferior vena cava hemodynamics under respiratory-induced collapse of the infrarenal IVC.

    Science.gov (United States)

    Tedaldi, Elisabetta; Montanari, Chiara; Aycock, Kenneth I; Sturla, Francesco; Redaelli, Alberto; Manning, Keefe B

    2018-04-01

    Inferior vena cava (IVC) filters have been used for over five decades as an alternative to anticoagulation therapy in the treatment of venous thromboembolic disease. However, complications associated with IVC filters remain common. Though many studies have investigated blood flow in the IVC, the effects of respiration-induced IVC collapse have not been evaluated. Our hypothesis is that IVC collapse may have an influence on IVC filter performance. Therefore, we herein investigate the hemodynamics in uncollapsed and collapsed IVC configurations using in vitro flow experiments and computational simulations. Particle image velocimetry (PIV) is used to measure the hemodynamics in an idealized, compliant model of the human IVC made of silicone rubber. Flow is studied under uncollapsed and collapsed scenarios, with the minor diameter of the IVC reduced by 30% in the collapsed state. Both rest and exercise flow conditions are investigated, corresponding to suprarenal flow rates of 2 lpm and 5.5 lpm, respectively. Finite element analysis simulations are carried out in a computational model of the undeformed, idealized IVC to reproduce the 30% collapse configuration and an additional 50% collapse configuration. Computational fluid dynamics (CFD) simulations are then performed to predict the flow in the uncollapsed and collapsed scenarios, and CFD results are compared to the experimental data. The results show that the collapsed states generate a higher velocity jet at the iliac junction that propagates farther into the lumen of the vena cava in comparison to the jet generated in the uncollapsed state. Moreover, 50% collapse of the IVC causes a shift of the jet away from the IVC wall and towards the center of the vena cava lumen. The area of maximum wall shear stress occurs where the jet impacts the wall and is larger in the collapsed scenarios. Secondary flow is also more complex in the collapsed scenarios. Interestingly, this study demonstrates that a small variation in

  19. Toward an Optimal Position for IVC Filters: Computational Modeling of the Impact of Renal Vein Inflow

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S L; Singer, M A

    2009-07-13

    The purpose of this report is to evaluate the hemodynamic effects of renal vein inflow and filter position on unoccluded and partially occluded IVC filters using three-dimensional computational fluid dynamics. Three-dimensional models of the TrapEase and Gunther Celect IVC filters, spherical thrombi, and an IVC with renal veins were constructed. Hemodynamics of steady-state flow was examined for unoccluded and partially occluded TrapEase and Gunther Celect IVC filters in varying proximity to the renal veins. Flow past the unoccluded filters demonstrated minimal disruption. Natural regions of stagnant/recirculating flow in the IVC are observed superior to the bilateral renal vein inflows, and high flow velocities and elevated shear stresses are observed in the vicinity of renal inflow. Spherical thrombi induce stagnant and/or recirculating flow downstream of the thrombus. Placement of the TrapEase filter in the suprarenal vein position resulted in a large area of low shear stress/stagnant flow within the filter just downstream of thrombus trapped in the upstream trapping position. Filter position with respect to renal vein inflow influences the hemodynamics of filter trapping. Placement of the TrapEase filter in a suprarenal location may be thrombogenic with redundant areas of stagnant/recirculating flow and low shear stress along the caval wall due to the upstream trapping position and the naturally occurring region of stagnant flow from the renal veins. Infrarenal vein placement of IVC filters in a near juxtarenal position with the downstream cone near the renal vein inflow likely confers increased levels of mechanical lysis of trapped thrombi due to increased shear stress from renal vein inflow.

  20. Rational design of competitive electrocatalysts for the oxygen reduction reaction in hydrogen fuel cells

    Science.gov (United States)

    Stolbov, Sergey; Alcántara Ortigoza, Marisol

    2012-02-01

    The large-scale application of one of the most promising clean and renewable sources of energy, hydrogen fuel cells, still awaits efficient and cost-effective electrocatalysts for the oxygen reduction reaction (ORR) occurring on the cathode. We demonstrate that truly rational design renders electrocatalysts possessing both qualities. By unifying the knowledge on surface morphology, composition, electronic structure and reactivity, we solve that sandwich-like structures are an excellent choice for optimization. Their constituting species couple synergistically yielding reaction-environment stability, cost-effectiveness and tunable reactivity. This cooperative-action concept enabled us to predict two advantageous ORR electrocatalysts. Density functional theory calculations of the reaction free-energy diagrams confirm that these materials are more active toward ORR than the so far best Pt-based catalysts. Our designing concept advances also a general approach for engineering materials in heterogeneous catalysis.

  1. Industry requirements for introduction of alternative energies with emphasis on hydrogen fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Delabbio, F. [Rio Tinto, Canadian Exploration Ltd., Toronto, ON (Canada); Starbuck, D. [Newmont Mining Corp., Denver, CO (United States); Akerman, A. [CVRD-Inco, Toronto, ON (Canada); Betournay, M.C. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Mining and Mineral Sciences Laboratories

    2007-07-01

    This paper discussed issues related to the use of alternate sources of energy in underground mining applications. Hydrogen power systems were examined in relation to operational drivers, available commercial supplies, site supplies, health and safety issues, capital and operating costs, mine production, and the role of government. Hydrogen power systems are being considered for mining applications in an effort to reduce greenhouse gas (GHG) emissions and reduce cooling and ventilation requirements. This article examined a range of issues that must be addressed before alternate energy systems such as hydrogen fuel cell technology can be used in larger-scale underground mining applications. The mining industry supports the development of new technologies. However, the introduction of alternate energy technologies must proceed in steps which include proof of concept testing, the development of generic infrastructure, power systems and regulations, and whole operating system studies. 13 refs., 1 fig.

  2. Development of sensors and sensing technology for hydrogen fuel cell vehicle applications

    Energy Technology Data Exchange (ETDEWEB)

    Brosha, Eric L [Los Alamos National Laboratory; Sekhar, Praveen K [Los Alamos National Laboratory; Mukundan, Rangchary [Los Alamos National Laboratory; Williamson, Todd L [Los Alamos National Laboratory; Barzon, Fernando H [Los Alamos National Laboratory; Woo, Leta Y [LLNL; Glass, Robert S [LLNL

    2010-01-01

    One related area of hydrogen fuel cell vehicle (FCV) development that cannot be overlooked is the anticipated requirement for new sensors for both the monitoring and control of the fuel cell's systems and for those devices that will be required for safety. Present day automobiles have dozens of sensors on-board including those for IC engine management/control, sensors for state-of-health monitoring/control of emissions systems, sensors for control of active safety systems, sensors for triggering passive safety systems, and sensors for more mundane tasks such as fluids level monitoring to name the more obvious. The number of sensors continues to grow every few years as a result of safety mandates but also in response to consumer demands for new conveniences and safety features.

  3. Hydrogen Fueling Station Using Thermal Compression: a techno-economic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kriha, Kenneth [Gas Technology Inst., Des Plaines, IL (United States); Petitpas, Guillaume [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Melchionda, Michael [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Soto, Herie [Shell, Houston TX (United States); Feng, Zhili [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Yanli [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-11

    The goal of this project was to demonstrate the technical and economic feasibility of using thermal compression to create the hydrogen pressure necessary to operate vehicle hydrogen fueling stations. The concept of utilizing the exergy within liquid hydrogen to build pressure rather than mechanical components such as compressors or cryogenic liquid pumps has several advantages. In theory, the compressor-less hydrogen station will have lower operating and maintenance costs because the compressors found in conventional stations require large amounts of electricity to run and are prone to mechanical breakdowns. The thermal compression station also utilizes some of the energy used to liquefy the hydrogen as work to build pressure, this is energy that in conventional stations is lost as heat to the environment.

  4. Fail-safe system for activity cooled supersonic and hypersonic aircraft. [using liquid hydrogen fuel

    Science.gov (United States)

    Jones, R. A.; Braswell, D. O.; Richie, C. B.

    1975-01-01

    A fail-safe-system concept was studied as an alternative to a redundant active cooling system for supersonic and hypersonic aircraft which use the heat sink of liquid-hydrogen fuel for cooling the aircraft structure. This concept consists of an abort maneuver by the aircraft and a passive thermal protection system (TPS) for the aircraft skin. The abort manuever provides a low-heat-load descent from normal cruise speed to a lower speed at which cooling is unnecessary, and the passive TPS allows the aircraft skin to absorb the abort heat load without exceeding critical skin temperature. On the basis of results obtained, it appears that this fail-safe-system concept warrants further consideration, inasmuch as a fail-safe system could possibly replace a redundant active cooling system with no increase in weight and would offer other potential advantages.

  5. Potential for air quality improvement in the Tokyo metropolitan area from use of hydrogen fuel

    International Nuclear Information System (INIS)

    Kruger, Paul; Murdock, Mork

    1998-01-01

    A revised estimation has been made of the local air quality improvement that can be achieved in Tokyo as a byproduct of a word-wide hydrogen energy economy based on global reduction of CO2 emission from fossil fuels. The study for the WE-NET Project in Japan examined the potential for reduction in nitrogen oxide emission with hydrogen fuel in the Tokyo metropolitan area where sufficient data exist on trends in population, vehicle registrations, traffic activity, and exhaust emissions. A dynamic model was developed to extrapolate the trends in these data to estimate future NOx emission rates in comparison to regulatory scenarios based on policy and technical decisions of the Tokyo Metropolitan Government for improvement of air quality in the metropolitan area. The results of the model show significant potential for reduction of NOx emission by the year 2020 with a concomitant reduction in mean roadside NOx concentration. (author)

  6. Cleaning the Air and Improving Health with Hydrogen Fuel-Cell Vehicles

    Science.gov (United States)

    Jacobson, M. Z.; Colella, W. G.; Golden, D. M.

    2005-06-01

    Converting all U.S. onroad vehicles to hydrogen fuel-cell vehicles (HFCVs) may improve air quality, health, and climate significantly, whether the hydrogen is produced by steam reforming of natural gas, wind electrolysis, or coal gasification. Most benefits would result from eliminating current vehicle exhaust. Wind and natural gas HFCVs offer the greatest potential health benefits and could save 3700 to 6400 U.S. lives annually. Wind HFCVs should benefit climate most. An all-HFCV fleet would hardly affect tropospheric water vapor concentrations. Conversion to coal HFCVs may improve health but would damage climate more than fossil/electric hybrids. The real cost of hydrogen from wind electrolysis may be below that of U.S. gasoline.

  7. Integrating a hydrogen fuel cell electric vehicle with vehicle-to-grid technology, photovoltaic power and a residential building

    NARCIS (Netherlands)

    Robledo, C.B.; Oldenbroek, V.D.W.M.; Abbruzzese, F.; van Wijk, A.J.M.

    2018-01-01

    This paper presents the results of a demonstration project, including building-integrated photovoltaic (BIPV) solar panels, a residential building and a hydrogen fuel cell electric vehicle (FCEV) for combined mobility and power generation, aiming to achieve a net zero-energy residential building

  8. Pathways to Commercial Success: Technologies and Products Supported by the Hydrogen, Fuel Cells and Infrastructure Technologies Program

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2009-08-01

    This report documents the results of an effort to identify and characterize commercial and near-commercial (emerging) technologies and products that benefited from the support of the Hydrogen, Fuel Cells and Infrastructure Technologies Program and its predecessor programs within DOE's Office of Energy Efficiency and Renewable Energy.

  9. Sonographic aorta/IVC cross-sectional area index for evaluation of dehydration in children.

    Science.gov (United States)

    Kwon, Hyuksool; Jung, Jae Yun; Lee, Jin Hee; Kwak, Young Ho; Kim, Do Kyun; Jung, Jin Hee; Chang, Ik Wan; Kim, Kyuseok

    2016-09-01

    Current studies have not found sufficient evidence to encourage the use of ultrasound for assessing dehydration in children. We introduce a new sonographic parameter, the "aorta/inferior vena cava (IVC) cross-sectional area index" (Ao/IVCA) measured just inferior to the xiphoid process, for the effective evaluation of dehydration in children. This is a prospective, observational study. We enrolled children who presented to the pediatric emergency department (PED) between May 2014 and January 2015. We measured the maximum diameter of the aorta from inner wall to inner wall, and the long and short axis diameters of IVC using a convex array transducer. Ao/IVCA was calculated and compared with aorta/IVC maximal diameter index (Ao/IVCD) and the clinical dehydration scale (CDS). A total of 34 children were enrolled. We found a statistically significant correlation between Ao/IVCA and CDS (R(2) = 0.30; P dehydration. The diagnostic performance of Ao/IVCA for dehydration might be higher than that of the method that uses the maximum diameter of IVC and the aorta. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Retrospective analysis of outcomes following inferior vena cava (IVC) filter placement in a managed care population.

    Science.gov (United States)

    Everhart, Damian; Vaccaro, Jamieson; Worley, Karen; Rogstad, Teresa L; Seleznick, Mitchel

    2017-08-01

    The role of inferior vena cava filter (IVC) filters for prevention of pulmonary embolism (PE) is controversial. This study evaluated outcomes of IVC filter placement in a managed care population. This retrospective cohort study evaluated data for individuals with Humana healthcare coverage 2013-2014. The study population included 435 recipients of prophylactic IVC filters, 4376 recipients of therapeutic filters, and two control groups, each matched to filter recipients. Patients were followed for up to 2 years. Post-index anticoagulant use, mortality, filter removal, device-related complications, and all-cause utilization. Adjusted regression analyses showed a positive association between filter placement and anticoagulant use at 3 months: odds ratio (ORs) 3.403 (95% CI 1.912-6.059), prophylactic; OR, 1.356 (95% CI 1.164-1.58), therapeutic. Filters were removed in 15.67% of prophylactic and 5.69% of therapeutic filter cases. Complication rates were higher with prophylactic procedures than with therapeutic procedures and typically exceeded 2% in the prophylactic group. Each form of filter placement was associated with increases in all-cause hospitalization (regression coefficient 0.295 [95% CI 0.093-0.498], prophylactic; 0.673 [95% CI 0.547-0.798], therapeutic) and readmissions (OR 2.444 [95% CI 1.298-4.602], prophylactic; 2.074 [95% CI 1.644-2.616], therapeutic). IVC filter placement in this managed care population was associated with increased use of anticoagulants and greater healthcare utilization compared to controls, low rates of retrieval, and notable rates of device-related complications, with effects especially pronounced in assessments of prophylactic filters. These findings underscore the need for appropriate use of IVC filters.

  11. Integration of direct carbon and hydrogen fuel cells for highly efficient power generation from hydrocarbon fuels

    Energy Technology Data Exchange (ETDEWEB)

    Muradov, Nazim; Choi, Pyoungho; Smith, Franklyn; Bokerman, Gary [Florida Solar Energy Center, University of Central Florida, 1679 Clearlake Road, Cocoa, FL 32922-5703 (United States)

    2010-02-15

    In view of impending depletion of hydrocarbon fuel resources and their negative environmental impact, it is imperative to significantly increase the energy conversion efficiency of hydrocarbon-based power generation systems. The combination of a hydrocarbon decomposition reactor with a direct carbon and hydrogen fuel cells (FC) as a means for a significant increase in chemical-to-electrical energy conversion efficiency is discussed in this paper. The data on development and operation of a thermocatalytic hydrocarbon decomposition reactor and its coupling with a proton exchange membrane FC are presented. The analysis of the integrated power generating system including a hydrocarbon decomposition reactor, direct carbon and hydrogen FC using natural gas and propane as fuels is conducted. It was estimated that overall chemical-to-electrical energy conversion efficiency of the integrated system varied in the range of 49.4-82.5%, depending on the type of fuel and FC used, and CO{sub 2} emission per kW{sub el}h produced is less than half of that from conventional power generation sources. (author)

  12. Transition to a hydrogen fuel cell transit bus fleet for Canadian urban transit system

    International Nuclear Information System (INIS)

    Ducharme, P.

    2004-01-01

    'Full text:' The Canadian Transportation Fuel Cell Alliance (CTFCA), created by the Canadian Government as part of its 2000 Climate Change Action Plan, has commissioned MARCON-DDM's Hydrogen Intervention Team (HIT) to provide a roadmap for urban transit systems that wish to move to hydrogen fuel cell-powered bus fleets. HIT is currently in the process of gathering information from hydrogen technology providers, bus manufacturers, fuelling system providers and urban transit systems in Canada, the US and Europe. In September, HIT will be in a position to provide a preview of its report to the CTFCA, due for October 2004. The planned table of contents includes: TOMORROW'S FUEL CELL (FC) URBAN TRANSIT BUS - Powertrain, on-board fuel technologies - FC engine system manufacturers - Bus technical specifications, performances, operating characteristics - FC bus manufacturers TOMORROW'S FC TRANSIT PROPERTY - Added maintenance, facilities and fuelling infrastructure requirements - Supply chain implications - Environmental and safety issues - Alternative operational concepts PATHWAYS TO THE FUTURE - Choosing the future operational concept - 'Gap' assessment - how long from here to there? - Facilities and fleet adjustments, including fuelling infrastructure - Risk mitigation, code compliance measures TRANSITIONAL CONSIDERATIONS - Cost implications - Transition schedule (author)

  13. Hydrogen Fuel Cell Analysis: Lessons Learned from Stationary Power Generation Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Scott E. Grasman; John W. Sheffield; Fatih Dogan; Sunggyu Lee; Umit O. Koylu; Angie Rolufs

    2010-04-30

    This study considered opportunities for hydrogen in stationary applications in order to make recommendations related to RD&D strategies that incorporate lessons learned and best practices from relevant national and international stationary power efforts, as well as cost and environmental modeling of pathways. The study analyzed the different strategies utilized in power generation systems and identified the different challenges and opportunities for producing and using hydrogen as an energy carrier. Specific objectives included both a synopsis/critical analysis of lessons learned from previous stationary power programs and recommendations for a strategy for hydrogen infrastructure deployment. This strategy incorporates all hydrogen pathways and a combination of distributed power generating stations, and provides an overview of stationary power markets, benefits of hydrogen-based stationary power systems, and competitive and technological challenges. The motivation for this project was to identify the lessons learned from prior stationary power programs, including the most significant obstacles, how these obstacles have been approached, outcomes of the programs, and how this information can be used by the Hydrogen, Fuel Cells & Infrastructure Technologies Program to meet program objectives primarily related to hydrogen pathway technologies (production, storage, and delivery) and implementation of fuel cell technologies for distributed stationary power. In addition, the lessons learned address environmental and safety concerns, including codes and standards, and education of key stakeholders.

  14. Dynamic behaviour of Li batteries in hydrogen fuel cell power trains

    Science.gov (United States)

    Veneri, O.; Migliardini, F.; Capasso, C.; Corbo, P.

    A Li ion polymer battery pack for road vehicles (48 V, 20 Ah) was tested by charging/discharging tests at different current values, in order to evaluate its performance in comparison with a conventional Pb acid battery pack. The comparative analysis was also performed integrating the two storage systems in a hydrogen fuel cell power train for moped applications. The propulsion system comprised a fuel cell generator based on a 2.5 kW polymeric electrolyte membrane (PEM) stack, fuelled with compressed hydrogen, an electric drive of 1.8 kW as nominal power, of the same typology of that installed on commercial electric scooters (brushless electric machine and controlled bidirectional inverter). The power train was characterized making use of a test bench able to simulate the vehicle behaviour and road characteristics on driving cycles with different acceleration/deceleration rates and lengths. The power flows between fuel cell system, electric energy storage system and electric drive during the different cycles were analyzed, evidencing the effect of high battery currents on the vehicle driving range. The use of Li batteries in the fuel cell power train, adopting a range extender configuration, determined a hydrogen consumption lower than the correspondent Pb battery/fuel cell hybrid vehicle, with a major flexibility in the power management.

  15. Scenarios for multi-unit inertial fusion energy plants producing hydrogen fuel

    International Nuclear Information System (INIS)

    Logan, B.G.

    1993-12-01

    This work describes: (a) the motivation for considering fusion in general, and Inertial Fusion Energy (IFE) in particular, to produce hydrogen fuel powering low-emission vehicles; (b) the general requirements for any fusion electric plant to produce hydrogen by water electrolysis at costs competitive with present consumer gasoline fuel costs per passenger mile, for advanced car architectures meeting President Clinton's 80 mpg advanced car goal, and (c) a comparative economic analysis for the potential cost of electricity (CoE) and corresponding cost of hydrogen (CoH) from a variety of multi-unit IFE plants with one to eight target chambers sharing a common driver and target fab facility. Cases with either heavy-ion or diode-pumped, solid-state laser drivers are considered, with ''conventional'' indirect drive target gains versus ''advanced, e.g. Fast Ignitor'' direct drive gain assumptions, and with conventional steam balance-of-plant (BoP) versus advanced MHD plus steam combined cycle BoP, to contrast the potential economics under ''conventional'' and ''advanced'' IFE assumptions, respectively

  16. A proposed model of factors influencing hydrogen fuel cell vehicle acceptance

    Science.gov (United States)

    Imanina, N. H. Noor; Kwe Lu, Tan; Fadhilah, A. R.

    2016-03-01

    Issues such as environmental problem and energy insecurity keep worsening as a result of energy use from household to huge industries including automotive industry. Recently, a new type of zero emission vehicle, hydrogen fuel cell vehicle (HFCV) has received attention. Although there are argues on the feasibility of hydrogen as the future fuel, there is another important issue, which is the acceptance of HFCV. The study of technology acceptance in the early stage is a vital key for a successful introduction and penetration of a technology. This paper proposes a model of factors influencing green vehicle acceptance, specifically HFCV. This model is built base on two technology acceptance theories and other empirical studies of vehicle acceptance. It aims to provide a base for finding the key factors influencing new sustainable energy fuelled vehicle, HFCV acceptance which is achieved by explaining intention to accept HFCV. Intention is influenced by attitude, subjective norm and perceived behavioural control from Theory of Planned Behaviour and personal norm from Norm Activation Theory. In the framework, attitude is influenced by perceptions of benefits and risks, and social trust. Perceived behavioural control is influenced by government interventions. Personal norm is influenced by outcome efficacy and problem awareness.

  17. Design of a Helium Vapor Shroud for Liquid Hydrogen Fueling of an Unmanned Aerial Vehicle (UAV)

    Science.gov (United States)

    Cavender, K.; Evans, C.; Haney, J.; Leachman, J.

    2017-12-01

    Filling a vehicular liquid hydrogen fuel tank presents the potential for flammable mixtures due to oxygen concentration from liquid air condensation. Current liquid hydrogen tank designs utilize insulating paradigms such as aerogel/fiberglass materials, vacuum jackets, or inert gas purge systems to keep the outer surface from reaching the condensation temperature of air. This work examines the heat transfer at the refuelling connection of the tank to identify potential areas of condensation, as well as the surface temperature gradient. A shrouded inert gas purge was designed to minimize vehicle weight and refuelling time. The design of a shrouded inert gas purge system is presented to displace air preventing air condensation. The design investigates 3D printed materials for an inert gas shroud, as well as low-temperature sealing designs. Shroud designs and temperature profiles were measured and tested by running liquid nitrogen through the filling manifold. Materials for the inert gas shroud are discussed and experimental results are compared to analytical model predictions. Suggestions for future design improvements are made.

  18. Conversion of a gasoline internal combustion engine to operate on hydrogen fuel

    International Nuclear Information System (INIS)

    Bates, M.; Dincer, I.

    2009-01-01

    This study deals with the conversion of a gasoline spark ignition internal combustion engine to operate on hydrogen fuel while producing similar power, economy and reliability as gasoline. The conversion engine will have the fuel system redesigned and ignition and fuel timing changed. Engine construction material is of great importance due to the low ignition energy of hydrogen, making aluminum a desirable material in the intake manifold and combustion chamber. The engine selected to convert is a 3400 SFI dual over head cam General Motors engine. Hydrogen reacts with metals causing hydrogen embrittlement which leads to failure due to cracking. There are standards published by American Society of Mechanical Engineers (ASME) to avoid such a problem. Tuning of the hydrogen engine proved to be challenging due to the basic tuning tools of a gasoline engine such as a wide band oxygen sensor that could not measure the 34:1 fuel air mixture needed for the hydrogen engine. Once the conversion was complete the engine was tested on a chassis dynamometer to compare the hydrogen horsepower and torque produced to that of a gasoline engine. Results showed that the engine is not operating correctly. The engine is not getting the proper amount of fuel needed for complete combustion when operated in a loaded state over 3000 rpm. The problem was found to be the use of the stock injector driver that could not deliver enough power for the proper operation of the larger CM4980 injectors. (author)

  19. Hydrogen fueling stations in Japan hydrogen and fuel cell demonstration project

    International Nuclear Information System (INIS)

    Koseki, K.; Tomuro, J.; Sato, H.; Maruyama, S.

    2004-01-01

    A new national demonstration project of fuel cell vehicles, which is called Japan Hydrogen and Fuel Cell Demonstration Project (JHFC Project), has started in FY2002 on a four-year plan. In this new project, ten hydrogen fueling stations have been constructed in Tokyo and Kanagawa area in FY2002-2003. The ten stations adopt the following different types of fuel and fueling methods: LPG reforming, methanol reforming, naphtha reforming, desulfurized-gasoline reforming, kerosene reforming, natural gas reforming, water electrolysis, liquid hydrogen, by-product hydrogen, and commercially available cylinder hydrogen. Approximately fifty fuel cell passenger cars and a fuel cell bus are running on public roads using these stations. In addition, two hydrogen stations will be constructed in FY2004 in Aichi prefecture where The 2005 World Exposition (EXPO 2005) will be held. The stations will service eight fuel cell buses used as pick-up buses for visitors. We, Engineering Advancement Association of Japan (ENAA), are commissioned to construct and operate a total of twelve stations by Ministry of Economy Trade and Industry (METI). We are executing to demonstrate or identify the energy-saving effect, reduction of the environmental footprint, and issues for facilitating the acceptance of hydrogen stations on the basis of the data obtained from the operation of the stations. (author)

  20. Mechanism and kinetics of the electrocatalytic reaction responsible for the high cost of hydrogen fuel cells.

    Science.gov (United States)

    Cheng, Tao; Goddard, William A; An, Qi; Xiao, Hai; Merinov, Boris; Morozov, Sergey

    2017-01-25

    The sluggish oxygen reduction reaction (ORR) is a major impediment to the economic use of hydrogen fuel cells in transportation. In this work, we report the full ORR reaction mechanism for Pt(111) based on Quantum Mechanics (QM) based Reactive metadynamics (RμD) simulations including explicit water to obtain free energy reaction barriers at 298 K. The lowest energy pathway for 4 e - water formation is: first, *OOH formation; second, *OOH reduction to H 2 O and O*; third, O* hydrolysis using surface water to produce two *OH and finally *OH hydration to water. Water formation is the rate-determining step (RDS) for potentials above 0.87 Volt, the normal operating range. Considering the Eley-Rideal (ER) mechanism involving protons from the solvent, we predict the free energy reaction barrier at 298 K for water formation to be 0.25 eV for an external potential below U = 0.87 V and 0.41 eV at U = 1.23 V, in good agreement with experimental values of 0.22 eV and 0.44 eV, respectively. With the mechanism now fully understood, we can use this now validated methodology to examine the changes upon alloying and surface modifications to increase the rate by reducing the barrier for water formation.

  1. Cryogenic hydrogen fuel for controlled inertial confinement fusion (formation of reactor-scale cryogenic targets)

    Energy Technology Data Exchange (ETDEWEB)

    Aleksandrova, I. V.; Koresheva, E. R., E-mail: elena.koresheva@gmail.com; Krokhin, O. N. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Osipov, I. E. [Power Efficiency Centre, Inter RAO UES (Russian Federation)

    2016-12-15

    In inertial fusion energy research, considerable attention has recently been focused on low-cost fabrication of a large number of targets by developing a specialized layering module of repeatable operation. The targets must be free-standing, or unmounted. Therefore, the development of a target factory for inertial confinement fusion (ICF) is based on methods that can ensure a cost-effective target production with high repeatability. Minimization of the amount of tritium (i.e., minimization of time and space at all production stages) is a necessary condition as well. Additionally, the cryogenic hydrogen fuel inside the targets must have a structure (ultrafine layers—the grain size should be scaled back to the nanometer range) that supports the fuel layer survivability under target injection and transport through the reactor chamber. To meet the above requirements, significant progress has been made at the Lebedev Physical Institute (LPI) in the technology developed on the basis of rapid fuel layering inside moving free-standing targets (FST), also referred to as the FST layering method. Owing to the research carried out at LPI, unique experience has been gained in the development of the FST-layering module for target fabrication with an ultrafine fuel layer, including a reactor- scale target design. This experience can be used for the development of the next-generation FST-layering module for construction of a prototype of a target factory for power laser facilities and inertial fusion power plants.

  2. CC8 MRSA strains harboring SCCmec type IVc are predominant in Colombian hospitals.

    Directory of Open Access Journals (Sweden)

    J Natalia Jiménez

    Full Text Available BACKGROUND: Recent reports highlight the incursion of community-associated MRSA within healthcare settings. However, knowledge of this phenomenon remains limited in Latin America. The aim of this study was to evaluate the molecular epidemiology of MRSA in three tertiary-care hospitals in Medellín, Colombia. METHODS: An observational cross-sectional study was conducted from 2008-2010. MRSA infections were classified as either community-associated (CA-MRSA or healthcare-associated (HA-MRSA, with HA-MRSA further classified as hospital-onset (HAHO-MRSA or community-onset (HACO-MRSA according to standard epidemiological definitions established by the U.S. Centers for Disease Control and Prevention (CDC. Genotypic analysis included SCCmec typing, spa typing, PFGE and MLST. RESULTS: Out of 538 total MRSA isolates, 68 (12.6% were defined as CA-MRSA, 243 (45.2% as HACO-MRSA and 227 (42.2% as HAHO-MRSA. The majority harbored SCCmec type IVc (306, 58.7%, followed by SCCmec type I (174, 33.4%. The prevalence of type IVc among CA-, HACO- and HAHO-MRSA isolates was 92.4%, 65.1% and 43.6%, respectively. From 2008 to 2010, the prevalence of type IVc-bearing strains increased significantly, from 50.0% to 68.2% (p = 0.004. Strains harboring SCCmec IVc were mainly associated with spa types t1610, t008 and t024 (MLST clonal complex 8, while PFGE confirmed that the t008 and t1610 strains were closely related to the USA300-0114 CA-MRSA clone. Notably, strains belonging to these three spa types exhibited high levels of tetracycline resistance (45.9%. CONCLUSION: CC8 MRSA strains harboring SCCmec type IVc are becoming predominant in Medellín hospitals, displacing previously reported CC5 HA-MRSA clones. Based on shared characteristics including SCCmec IVc, absence of the ACME element and tetracycline resistance, the USA300-related isolates in this study are most likely related to USA300-LV, the recently-described 'Latin American variant' of USA300.

  3. Effect of Room Ventilation Rates in Rodent Rooms with Direct-Exhaust IVC Systems.

    Science.gov (United States)

    Geertsema, Roger S; Lindsell, Claire E

    2015-09-01

    When IVC are directly exhausted from a rodent housing room, the air quality of the room can become independent of the intracage air quality and may reduce the need for high room ventilation rates. This study assessed the effect of decreasing the ventilation rate in rodent rooms using direct-exhaust IVC systems. The study was conducted over 16 wk and compared conditions in 8 rodent rooms that had ventilation rates of 5 to 6 air changes per hour (ACH) with those in rooms at 10 to 12 ACH. At the low ventilation rate, rooms had higher CO₂ concentrations, higher dew point temperature, and lower particulate levels and spent a greater percentage of time above the temperature set point than did rooms at the high rate. The levels of allergens and endotoxins in room air were the same regardless of the ventilation rate. Differences seen in parameters within cages at the 2 ventilation rates were operationally irrelevant. We detected no total volatile organic compounds in the room that were attributable to ammonia, regardless of the ventilation rate. Clearing the air of ethanol after a spill took longer at the low compared with high rate. However, ethanol clearance was faster at the low rate when the demand-control system was activated than at the high ventilation rate alone. Air quality in the room and in the cages were acceptable with room ventilation rates of 5 to 6 ACH in rodent rooms that use direct-exhaust IVC systems.

  4. The mid-term efficacy and safety of a permanent nitinol IVC filter (TrapEase)

    International Nuclear Information System (INIS)

    Liu, Wei Chiang; Do, Young Soo; Choo, Sung Wook; Kim, Dong Ik; Kim, Young Wook; Kim, Duk Kyung; Shin, Sung Wook; Park, Kwang Bo; Jeon, Yong Hwan; Choo, In Wook

    2005-01-01

    1) To evaluate the mid-term efficacy and safety of a permanent nitinol inferior vena cava (IVC) filter; 2) to evaluate filter effectiveness, filter stability and caval occlusion. A prospective evaluation of the TrapEase IVC filter was performed on 42 patients (eight men, 34 women) ranging in age from 22 to 78 years (mean age 66 years). All patients were ill with a high risk of pulmonary embolism (PE). Indications for filter placement were: 1) deep vein thrombosis with recurrent thromboembolism; 2) and/or free-floating thrombus with contraindication to anticoagulation; and 3) complications in achieving adequate anticoagulation. Follow-up evaluations (mean: 15.4 months, range: 2 to 28 months) were performed at 6- and 12-month intervals after the procedure and included clinical histories, chart reviews, plain film, Doppler ultrasounds, and contrasted abdominal CT scans. In follow-up evaluations, the data analysis revealed no cases of symptomatic PE. There were no cases of filter migration, insertion site thrombosis, filter fracture, or vessel wall perforation. During the study, there was one case of filter thrombosis; early symptomatic thrombosis that was successfully treated in the hospital. Of the 42 subjects, eight dead. These deaths were not related to the filter device or the implantation procedure, but to the underlying disease. This study demonstrates that the TrapEase permanent IVC filter is a safe and an effective device with low complication rates and is best used in patients with thromboembolic disease with a high risk of PE

  5. Importance of hydrogen fuels as sustainable alternative energy for domestic and industrial applications

    International Nuclear Information System (INIS)

    Sharifan, H.R.; Banan, N.; Davari, A.

    2009-01-01

    Energy demand is increasing continuously due to rapid growth in population and industrialization development. As a result greenhouse gases especially CO 2 produced by the combustion of fossil fuels cause depletion of fossil fuels and deterioration of environmental conditions worldwide. The goal of global energy sustainability implies the replacement of all fossil fuels by renewable energy sources . Hydrogen fuel is one of the sustainable energy sources can be available by conversion of biomass into biological hydrogen gas and ethanol. Rate of biomass generation in domestic wastes in Iranian culture is high. Therefore there is suitable potential for hydrogen generation in rural and urban areas of Iran. On the other hand energy extraction from these fossil fuels causes pollution and diseases. Globally, hydrogen is already produced in significant quantities (around 5 billion cubic metres per annum). It is mainly used to produce ammonia for fertiliser (about 50%), for oil refining (37%), methanol production (8%) and in the chemical and metallurgical industries (4%). On the other hand, increase in emissions rates of greenhouse gases, i.e., CO 2 present a threat to the world climate. Also new legislation of Iran has been approved the higher costs of conventional fuels for consuming in vehicles for reduction of greenhouse gases reduction as environmental policies. Demand is rising in all cities of Iran for cleaner fuels such as mixed fuels and natural gas, but unfortunately they are exporting to foreign countries or the required technologies are not available and economically option. Nuclear industries in Iran are also small and expanding only slowly. So importance of alternative energies as hydrogen powers are increasing daily. Presently both major consumers of domestic and industrial such as plants and manufacturers are using fossil fuels for their process that consequently contribute to the global warming and climate change. This paper reviews these options, with

  6. Lightweight Design and Welding Manufacturing of a Hydrogen Fuel Cell Powered Car’s Chassis

    Directory of Open Access Journals (Sweden)

    Evangelos Ch. Tsirogiannis

    2018-05-01

    Full Text Available The development of the chassis for the hydrogen fuel cell powered car has been involved in the designing and manufacturing aspects, while taking into consideration the mass, strength, stiffness, centre of gravity (COG, and manufacturing cost requirements. Towards this direction, a chassis design is proposed employing a space frame structure and constructed by an aluminium alloy with great strength. The structural design has been derived through the lightweight engineering approaches in conjunction with the part consolidation, Design for Assembly (DFA and Design for Manufacture methods. Moreover, it has been performed in compliance with the safety regulations of the Shell Eco Marathon racing competition. The material’s principal characteristics are the great strength, the low mass, as well as the great workability, machinability, and weldability. Following the national and global environmental issues, the recyclable characteristics of the aluminium alloy are an extra asset. Furthermore, the existence of aluminium alloy manufacturers around the fabricating area provides low cost supply and fast delivery benefits. The integration of the fuel cell powered vehicle is obtained through the designing and the manufacturing processes of the chassis and the parts fitted on the chassis. The manufacturing procedures are described thoroughly; mainly consisting of the cutting and welding processes and the assembling of the parts that are fitted on the chassis. Additionally, the proper welding parameters for the custom chassis design are investigated and are selected after deductive reasoning. The quality control of the weld joints is conducted by non-destructive methods (NDT ensuring the required structural properties of the welds. A combination of the selected material, the specific type of the chassis, and the manufacturing processes lead to construction simplicity in a low manufacturing cost by using the existing laboratory equipment. Furthermore, the

  7. High Efficiency Generation of Hydrogen Fuels Using Solar Thermochemical Splitting of Water

    Energy Technology Data Exchange (ETDEWEB)

    Heske, Clemens; Moujaes, Samir; Weimer, Alan; Wong, Bunsen; Siegal, Nathan; McFarland, Eric; Miller, Eric; Lewis, Michele; Bingham, Carl; Roth, Kurth; Sabacky, Bruce; Steinfeld, Aldo

    2011-09-29

    The objective of this work is to identify economically feasible concepts for the production of hydrogen from water using solar energy. The ultimate project objective was to select one or more competitive concepts for pilot-scale demonstration using concentrated solar energy. Results of pilot scale plant performance would be used as foundation for seeking public and private resources for full-scale plant development and testing. Economical success in this venture would afford the public with a renewable and limitless source of energy carrier for use in electric power load-leveling and as a carbon-free transportation fuel. The Solar Hydrogen Generation Research (SHGR) project embraces technologies relevant to hydrogen research under the Office of Hydrogen Fuel Cells and Infrastructure Technology (HFCIT) as well as concentrated solar power under the Office of Solar Energy Technologies (SET). Although the photoelectrochemical work is aligned with HFCIT, some of the technologies in this effort are also consistent with the skills and technologies found in concentrated solar power and photovoltaic technology under the Office of Solar Energy Technologies (SET). Hydrogen production by thermo-chemical water-splitting is a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or a combination of heat and electrolysis instead of pure electrolysis and meets the goals for hydrogen production using only water and renewable solar energy as feed-stocks. Photoelectrochemical hydrogen production also meets these goals by implementing photo-electrolysis at the surface of a semiconductor in contact with an electrolyte with bias provided by a photovoltaic source. Here, water splitting is a photo-electrolytic process in which hydrogen is produced using only solar photons and water as feed-stocks. The thermochemical hydrogen task engendered formal collaborations among two universities, three national laboratories and two private sector

  8. Impact of Anticoagulation in Elderly Patients With Pulmonary Embolism That Undergo IVC Filter Placement: A Retrospective Cohort Study.

    Science.gov (United States)

    Falatko, John M; Dalal, Bhavinkumar; Qu, Lihua

    2017-12-01

    Anticoagulation is the primary treatment for pulmonary embolism (PE). Inferior vena cava (IVC) filters are an adjunctive intervention to prevent recurrent pulmonary embolism. Long-term outcomes in elderly patients with contraindications to anticoagulation after IVC filter placement for prevention of recurrent pulmonary embolism have yet to be assessed. Patients ≥60years of age, that had an IVC filter placed between 1 January, 2008 and 2 February, 2013, with a primary diagnosis of pulmonary embolism, were included. Patients that died during index hospitalisation, were discharged to hospice, or had active malignancy were excluded. The primary endpoint was overall survival. Patients were divided depending on whether they were treated with an approved anticoagulant for VTE or had no anticoagulant. Of the 152 patients identified, 55 were not anti-coagulated after IVC filter placement. The incidence of death was 0.4 per 1000 filter days and 0.7 per 1000 filter days in the anti-coagulated and untreated groups respectively (p-value=0.06). After statistical correction for co-morbid conditions, the effect of anticoagulation was not significant (HR 0.82 CI 0.49-1.37, p-value 0.46). Age was a significant confounder that was associated with death. Increased BMI was protective. Indications for IVC filter placement were numerous, but similar between the two groups. Treatment with an approved anticoagulant is recommended after IVC filter placement for prevention of recurrent PE, however its effect may be attenuated by advanced age. In elderly patients that have undergone IVC filter placement for prevention of recurrent PE, survival may be more dependent on age and co-morbid conditions than exposure to anticoagulation. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  9. The effect of IVM and IVC media on in vitro development of bovine embryos

    Directory of Open Access Journals (Sweden)

    E.T Mergawati

    2000-12-01

    Full Text Available The purpose of this study was to examine the effect of medium combination of IVM and IVC on the in vitro development of bovine embryos. The study involved 4 groups in a 2 (IVM medium x 2 (IVC medium factorial in a randomized block design. Each group was replicated for 5 times. The treatments were as follows: TCM-199/CR1aa (T1; TCM-199/SOF (T2; B- 199/CR1aa (T3 and B-199/SOF (T4. Oocytes were aspirated from ovaries collected at local abattoirs using aspiration medium of PBS supplemented with 3% FCS and 0.1% Penicillin and Streptomycin. The oocytes were matured in medium of TCM-199 or B-199 supplemented with 10% FCS, hormones: 10μg/ml FSH+ 10μg/ml hCG+ 1μg/ml Estradiol. Maturation was maintained at 37oC for 22 hours in 5% CO2 incubator with high humidity. A method of BRACKETT & Oliphant (BO was used to fertilize the matured oocytes. The fertilization was incubated for 7 hours in the 5% CO2 incubator. Two culture media of CR1aa or SOF/AA/BSA were used to develop the fertilized oocytes undergo to morula and blastocyst embryos. The findings showed that the proportion of oocytes cleaved and formation of blastocysts were affected significantly by a combination of IVM and IVC media (P<0.05. A combination of B-199/SOF (T4 resulted in a higher blastocyst rate (32% than others (T3= 29%; T2=T1= 23%. This study suggests that either SOF/AA/BSA or CR1aa has similar competence in development of bovine embryos in vitro.

  10. Complex Retrieval of Embedded IVC Filters: Alternative Techniques and Histologic Tissue Analysis

    International Nuclear Information System (INIS)

    Kuo, William T.; Cupp, John S.; Louie, John D.; Kothary, Nishita; Hofmann, Lawrence V.; Sze, Daniel Y.; Hovsepian, David M.

    2012-01-01

    Purpose: We evaluated the safety and effectiveness of alternative endovascular methods to retrieve embedded optional and permanent filters in order to manage or reduce risk of long-term complications from implantation. Histologic tissue analysis was performed to elucidate the pathologic effects of chronic filter implantation. Methods: We studied the safety and effectiveness of alternative endovascular methods for removing embedded inferior vena cava (IVC) filters in 10 consecutive patients over 12 months. Indications for retrieval were symptomatic chronic IVC occlusion, caval and aortic perforation, and/or acute PE (pulmonary embolism) from filter-related thrombus. Retrieval was also performed to reduce risk of complications from long-term filter implantation and to eliminate the need for lifelong anticoagulation. All retrieved specimens were sent for histologic analysis. Results: Retrieval was successful in all 10 patients. Filter types and implantation times were as follows: one Venatech (1,495 days), one Simon-Nitinol (1,485 days), one Optease (300 days), one G2 (416 days), five Günther-Tulip (GTF; mean 606 days, range 154–1,010 days), and one Celect (124 days). There were no procedural complications or adverse events at a mean follow-up of 304 days after removal (range 196–529 days). Histology revealed scant native intima surrounded by a predominance of neointimal hyperplasia and dense fibrosis in all specimens. Histologic evidence of photothermal tissue ablation was confirmed in three laser-treated specimens. Conclusion: Complex retrieval methods can now be used in select patients to safely remove embedded optional and permanent IVC filters previously considered irretrievable. Neointimal hyperplasia and dense fibrosis are the major components that must be separated to achieve successful retrieval of chronic filter implants.

  11. Melanotic Xp11 Translocation Renal Cancer Managed With Radical Nephrectomy and IVC Tumor Thrombectomy

    Directory of Open Access Journals (Sweden)

    Iyad S. Khourdaji

    2017-01-01

    Full Text Available Melanotic Xp11 translocation renal cancer is a rarely observed neoplasm primarily affecting adolescents and young adults. Given the paucity of data describing this malignancy, its natural history and subsequent long-term management are not well understood. We report a case of melanotic Xp11 translocation with tumor thrombus extension managed with radical nephrectomy and inferior vena cava (IVC tumor thrombectomy. To our knowledge, this is the first case report to describe use of conventional tumor thrombectomy techniques in a patient with melanotic Xp11 translocation renal cancer.

  12. Correlation of inferior vena cava (ivc) diameter and central venous pressure (cvp) for fluid monitoring in icu

    International Nuclear Information System (INIS)

    Khalil, A.; Hayat, A.

    2015-01-01

    To determine intravascular fluid status in critically ill patients using inferior vena cava diameter and correlating it with central venous pressure. Study Design: Cross sectional study. Place and Duration of Study: Intensive care department, Military Hospital Rawalpindi from Jan 2013 to Aug 2013. Material and Methods: We included 115 adult patients of both genders in age range of 18 to 87 years by consecutive sampling admitted in intensive care unit. Ultrasound guided IVC diameter was assessed in supine patients. Data was simultaneously collected from the CVP catheter. Variables included in study were age, gender, CVP, IVC diameter. Results: CVP ranged from -4 to 26 cm H/sub 2/O with mean of 8 cm H/sub 2/O (SD = 6.24). Mean IVC diameters increased with increase in CVP. Correlation between CVP and max IVC diameter was moderate and significant (r = 0.53, p < 0.001). Correlation between CVP and min IVC diameter was also moderate and significant (r = 0.58, p < 0.001). Conclusion: A simple bedside sonography of inferior vena cava diameter correlates well with extremes of CVP values and can be helpful in assessing intravascular fluid status in these patients. (author)

  13. Sonographic evaluation of intravascular volume status: Can internal jugular or femoral vein collapsibility be used in the absence of IVC visualization?

    Directory of Open Access Journals (Sweden)

    Alistair Kent

    2015-01-01

    Full Text Available Introduction: Inferior vena cava collapsibility index (IVC-CI has been shown to correlate with both clinical and invasive assessment of intravascular volume status, but has important limitations such as the requirement for advanced sonographic skills, the degree of difficulty in obtaining those skills, and often challenging visualization of the IVC in the postoperative patient. The current study aims to explore the potential for using femoral (FV or internal jugular (IJV vein collapsibility as alternative sonographic options in the absence of adequate IVC visualization. Methods: A prospective, observational study comparing IVC-CI and Fem- and/or IJV-CI was performed in two intensive care units (ICU between January 2012 and April 2014. Concurrent M-mode measurements of IVC-CI and FV- and/or IJV-CI were collected during each sonographic session. Measurements of IVC were obtained using standard technique. IJV-CI and FV-CI were measured using high-frequency, linear array ultrasound probe placed in the corresponding anatomic areas. Paired data were analyzed using coefficient of correlation/determination and Bland-Altman determination of measurement bias. Results: We performed paired ultrasound examination of IVC-IJV (n = 39 and IVC-FV (n = 22, in 40 patients (mean age 54.1; 40% women. Both FV-CI and IJV-CI scans took less time to complete than IVC-CI scans (both, P < 0.02. Correlations between IVC-CI/FV-CI (R 2 = 0.41 and IVC-CI/IJV-CI (R 2 = 0.38 were weak. There was a mean -3.5% measurement bias between IVC-CI and IJV-CI, with trend toward overestimation for IJV-CI with increasing collapsibility. In contrast, FV-CI underestimated collapsibility by approximately 3.8% across the measured collapsibility range. Conclusion: Despite small measurement biases, correlations between IVC-CI and FV-/IJV-CI are weak. These results indicate that IJ-CI and FV-CI should not be used as a primary intravascular volume assessment tool for clinical decision support in

  14. Comparative analysis of battery electric, hydrogen fuel cell and hybrid vehicles in a future sustainable road transport system

    International Nuclear Information System (INIS)

    Offer, G.J.; Howey, D.; Contestabile, M.; Clague, R.; Brandon, N.P.

    2010-01-01

    This paper compares battery electric vehicles (BEV) to hydrogen fuel cell electric vehicles (FCEV) and hydrogen fuel cell plug-in hybrid vehicles (FCHEV). Qualitative comparisons of technologies and infrastructural requirements, and quantitative comparisons of the lifecycle cost of the powertrain over 100,000 mile are undertaken, accounting for capital and fuel costs. A common vehicle platform is assumed. The 2030 scenario is discussed and compared to a conventional gasoline-fuelled internal combustion engine (ICE) powertrain. A comprehensive sensitivity analysis shows that in 2030 FCEVs could achieve lifecycle cost parity with conventional gasoline vehicles. However, both the BEV and FCHEV have significantly lower lifecycle costs. In the 2030 scenario, powertrain lifecycle costs of FCEVs range from $7360 to $22,580, whereas those for BEVs range from $6460 to $11,420 and FCHEVs, from $4310 to $12,540. All vehicle platforms exhibit significant cost sensitivity to powertrain capital cost. The BEV and FCHEV are relatively insensitive to electricity costs but the FCHEV and FCV are sensitive to hydrogen cost. The BEV and FCHEV are reasonably similar in lifecycle cost and one may offer an advantage over the other depending on driving patterns. A key conclusion is that the best path for future development of FCEVs is the FCHEV.

  15. Comparative analysis of battery electric, hydrogen fuel cell and hybrid vehicles in a future sustainable road transport system

    Energy Technology Data Exchange (ETDEWEB)

    Offer, G.J.; Brandon, N.P. [Department Earth Science Engineering, Imperial College London, SW7 2AZ (United Kingdom); Howey, D. [Department of Electrical and Electronic Engineering, Imperial College London, SW7 2AZ (United Kingdom); Contestabile, M. [Centre for Environmental Policy, Imperial College London, SW7 2AZ (United Kingdom); Clague, R. [Energy Futures Lab, Imperial College London, SW7 2AZ (United Kingdom)

    2010-01-15

    This paper compares battery electric vehicles (BEV) to hydrogen fuel cell electric vehicles (FCEV) and hydrogen fuel cell plug-in hybrid vehicles (FCHEV). Qualitative comparisons of technologies and infrastructural requirements, and quantitative comparisons of the lifecycle cost of the powertrain over 100,000 mile are undertaken, accounting for capital and fuel costs. A common vehicle platform is assumed. The 2030 scenario is discussed and compared to a conventional gasoline-fuelled internal combustion engine (ICE) powertrain. A comprehensive sensitivity analysis shows that in 2030 FCEVs could achieve lifecycle cost parity with conventional gasoline vehicles. However, both the BEV and FCHEV have significantly lower lifecycle costs. In the 2030 scenario, powertrain lifecycle costs of FCEVs range from $7360 to $22,580, whereas those for BEVs range from $6460 to $11,420 and FCHEVs, from $4310 to $12,540. All vehicle platforms exhibit significant cost sensitivity to powertrain capital cost. The BEV and FCHEV are relatively insensitive to electricity costs but the FCHEV and FCV are sensitive to hydrogen cost. The BEV and FCHEV are reasonably similar in lifecycle cost and one may offer an advantage over the other depending on driving patterns. A key conclusion is that the best path for future development of FCEVs is the FCHEV. (author)

  16. IVC filter placements in children: nationwide comparison of practice patterns at adult and children's hospitals using the Kids' Inpatient Database.

    Science.gov (United States)

    Wadhwa, Vibhor; Trivedi, Premal S; Ali, Sumera; Ryu, Robert K; Pezeshkmehr, Amir

    2018-02-01

    Inferior vena cava (IVC) filter placement in children has been described in literature, but there is variability with regard to their indications. No nationally representative study has been done to compare practice patterns of filter placements at adult and children's hospitals. To perform a nationally representative comparison of IVC filter placement practices in children at adult and children's hospitals. The 2012 Kids' Inpatient Database was searched for IVC filter placements in children filter insertion (38.7), IVC filter placements were identified. A small number of children with congenital cardiovascular anomalies codes were excluded to improve specificity of the code used to identify filter placement. Filter placements were further classified by patient demographics, hospital type (children's and adult), United States geographic region, urban/rural location, and teaching status. Statistical significance of differences between children's or adult hospitals was determined using the Wilcoxon rank sum test. A total of 618 IVC filter placements were identified in children filters were placed in the setting of venous thromboembolism in children's hospitals (40/44, 90%) compared to adult hospitals (246/573, 43%) (Pfilters comprised 327/573 (57%) at adult hospitals, with trauma being the most common indication (301/327, 92%). The mean length of stay for patients receiving filters was 24.5 days in children's hospitals and 18.4 days in adult hospitals. The majority of IVC filters in children are placed in adult hospital settings. Children's hospitals are more likely to place therapeutic filters for venous thromboembolism, compared to adult hospitals where the prophylactic setting of trauma predominates.

  17. Initial Screening of Thermochemical Water-Splitting Cycles for High Efficiency Generation of Hydrogen Fuels Using Nuclear Power

    International Nuclear Information System (INIS)

    Brown, L.C.; Funk, J.F.; Showalter, S.K.

    1999-01-01

    OAK B188 Initial Screening of Thermochemical Water-Splitting Cycles for High Efficiency Generation of Hydrogen Fuels Using Nuclear Power There is currently no large scale, cost-effective, environmentally attractive hydrogen production process, nor is such a process available for commercialization. Hydrogen is a promising energy carrier, which potentially could replace the fossil fuels used in the transportation sector of our economy. Fossil fuels are polluting and carbon dioxide emissions from their combustion are thought to be responsible for global warming. The purpose of this work is to determine the potential for efficient, cost-effective, large-scale production of hydrogen utilizing high temperature heat from an advanced nuclear power station. Almost 800 literature references were located which pertain to thermochemical production of hydrogen from water and over 100 thermochemical watersplitting cycles were examined. Using defined criteria and quantifiable metrics, 25 cycles have been selected for more detailed study

  18. Final Project Closeout Report for Sprint Hydrogen Fuel Cell (HFC) Deployment Project in California, Gulf Coast and Eastern Seaboard Markets

    Energy Technology Data Exchange (ETDEWEB)

    Kenny, Kevin [Sprint, Reston, VA (United States); Bradley, Dwayne [Burns & McDonnell, Kansas City, MO (United States)

    2015-09-01

    Sprint is one of the telecommunications industry leaders in the deployment of hydrogen fuel cell (HFC) systems to provide backup power for their mission critical wireless network facilities. With several hundred fuel cells commissioned in California, states in the gulf coast region, and along the upper eastern seaboard. A strong incentive for advancing the integration of fuel cells into the Sprint network came through the award of a Department of Energy (DOE) grant focused on Market Transformation activities for project (EE0000486). This grant was funded by the 2009 American Recovery and Reinvestment Act (ARRA). The funding provided by DOE ($7.295M) was allocated to support the installation of 260 new HFC systems, equipped with an on-site refillable Medium Pressure Hydrogen Storage Solution (MPHSS), as well as for the conversion of 21 low pressure hydrogen systems to the MPHSS, in hopes of reducing barriers to market acceptance.

  19. Evaluation of a Hydrogen Fuel Cell Powered Blended-Wing-Body Aircraft Concept for Reduced Noise and Emissions

    Science.gov (United States)

    Guynn, Mark D.; Freh, Joshua E.; Olson, Erik D.

    2004-01-01

    This report describes the analytical modeling and evaluation of an unconventional commercial transport aircraft concept designed to address aircraft noise and emission issues. A blended-wing-body configuration with advanced technology hydrogen fuel cell electric propulsion is considered. Predicted noise and emission characteristics are compared to a current technology conventional configuration designed for the same mission. The significant technology issues which have to be addressed to make this concept a viable alternative to current aircraft designs are discussed. This concept is one of the "Quiet Green Transport" aircraft concepts studied as part of NASA's Revolutionary Aerospace Systems Concepts (RASC) Program. The RASC Program was initiated to develop revolutionary concepts that address strategic objectives of the NASA Enterprises, such as reducing aircraft noise and emissions, and to identify advanced technology requirements for the concepts.

  20. Balancing low cost with reliable operation in the rotordynamic design of the ALS Liquid Hydrogen Fuel Turbopump

    Science.gov (United States)

    Greenhill, L. M.

    1990-01-01

    The Air Force/NASA Advanced Launch System (ALS) Liquid Hydrogen Fuel Turbopump (FTP) has primary design goals of low cost and high reliability, with performance and weight having less importance. This approach is atypical compared with other rocket engine turbopump design efforts, such as on the Space Shuttle Main Engine (SSME), which emphasized high performance and low weight. Similar to the SSME turbopumps, the ALS FTP operates supercritically, which implies that stability and bearing loads strongly influence the design. In addition, the use of low cost/high reliability features in the ALS FTP such as hydrostatic bearings, relaxed seal clearances, and unshrouded turbine blades also have a negative influence on rotordynamics. This paper discusses the analysis conducted to achieve a balance between low cost and acceptable rotordynamic behavior, to ensure that the ALS FTP will operate reliably without subsynchronous instabilities or excessive bearing loads.

  1. Density and magnetic field measurements in the Tormac IV-c plasma

    International Nuclear Information System (INIS)

    Coonrod, J.W. Jr.

    1978-01-01

    Tormac is a concept for magnetically confining a high-β fusion plasma in a toroidal, stuffed line cusp. A Tormac plasma has two regions: an interior confined on the closed toroidal field lines of the stuffing field, and an exterior sheath on open, cusped field lines. The interior plasma gives the device a longer confinement time than a standard mirror, while the favorable curvature of the cusp fields allow the plasma to be stable at higher values of β (the ratio of the plasma pressure to magnetic pressure) than a totally closed configuration like Tokamak. This thesis describes the design, construction and operation of Tormac IV-c, and reports on the results, with emphasis on describing the behavior of the density compression and field penetration

  2. Hydrogen Fuel Cell Vehicle Fuel Economy Testing at the U.S. EPA National Vehicle and Fuel Emissions Laboratory (SAE Paper 2004-01-2900)

    Science.gov (United States)

    The introduction of hydrogen fuel cell vehicles and their new technology has created the need for development of new fuel economy test procedures and safety procedures during testing. The United States Environmental Protection Agency-National Vehicle Fuels and Emissions Laborato...

  3. An Application of the PMI Model at the Project Level Evaluation of ESEA Title IV-C Projects.

    Science.gov (United States)

    McBeath, Marcia

    All of the papers presented as part of a symposium concerned the application of the Planning, Monitoring, and Implementation Model (PMI) to the evaluation of the District of Columbia Public Schools' programs supported by the Elementary Secondary Education Act (ESEA) Title IV-C. PMI was developed to provide a model for systematic evaluation of…

  4. Long-Term Retrievability of IVC Filters: Should We Abandon Permanent Devices?

    International Nuclear Information System (INIS)

    Berczi, V.; Bottomley, J. R.; Thomas, S. M.; Taneja, S.; Gaines, P. A.; Cleveland, T. J.

    2007-01-01

    Thromboembolic disease produces a considerable disease burden, with death from pulmonary embolism in the UK alone estimated at 30,000-40,000 per year. Whilst it is unproven whether filters actually improve longevity, the morbidity and mortality associated with thromboembolic disease in the presence of contraindications to anticoagulation is high. Thus complications associated with filter insertion, and whilst they remain in situ, must be balanced against the alternatives. Permanent filters remain in situ for the remainder of the patient's life and any complications from the filters are of significant concern. Filters that are not permanent are therefore attractive in these circumstances. Retrievable filters, to avoid or decrease long-term filter complications, appear to be a significant advance in the prevention of pulmonary embolism. In this review, we discuss the safety and effectiveness of both permanent and retrievable filters as well as the retrievability of retrievable inferior vena cava (IVC) filters, to explore whether the use of permanent IVC filters can be abandoned in favor of retrievable filters. Currently four types of retrievable filters are available: the Recovery filter (Bard Peripheral Vascular, Tempe, AZ, USA), the Guenther Tulip filter (Cook, Bloomington, IN, USA), the OptEase Filter (Cordis, Roden, The Netherlands), and the ALN filter (ALN Implants Chirurgicaux, Ghisonaccia, France). Efficacy and safety data for retrievable filters are as yet based on small series, with a total number of fewer than 1,000 insertions, and follow-up is mostly short term. Current long-term data are poor and insufficient to warrant the long-term implantation of these devices into humans. The case of fractured wire from a Recovery filter that migrated to the heart causing pericardial tamponade requiring open heart surgery is a reminder that any new endovascular device remaining in situ in the long term may produce unexpected problems. We should also bear in mind that

  5. Action plan for coordinated deployment of hydrogen fuel cell vehicles and hydrogen infrastructure

    International Nuclear Information System (INIS)

    Elrick, W.

    2009-01-01

    This paper discussed a program designed to provide hydrogen vehicles and accessible hydrogen stations for a pre-commercial hydrogen economy in California. The rollout will coordinate the placement of stations in areas that meet the needs of drivers in order to ensure the transition to a competitive marketplace. An action plan has been developed that focuses on the following 3 specific steps: (1) the validation of early passenger vehicle markets, (2) expanded transit bus use, and (2) the establishment of regulations and standards. Specific tasks related to the steps were discussed, as well as potential barriers to the development of a hydrogen infrastructure in California. Methods of ensuring coordinated actions with the fuel cell and hydrogen industries were also reviewed

  6. Radiology-led Follow-up System for IVC Filters: Effects on Retrieval Rates and Times

    International Nuclear Information System (INIS)

    Lee, L.; Taylor, J.; Munneke, G.; Morgan, R.; Belli, A.-M.

    2012-01-01

    Purpose: Successful IVC filter retrieval rates fall with time. Serious complications have been reported following attempts to remove filters after 3–18 months. Failed retrieval may be associated with adverse clinical sequelae. This study explored whether retrieval rates are improved if interventional radiologists organize patient follow-up, rather than relying on the referring clinicians. Methods: Proactive follow-up of patients who undergo filter placement was implemented in May 2008. At the time of filter placement, a report was issued to the referring consultant notifying them of the advised timeframe for filter retrieval. Clinicians were contacted to arrange retrieval within 30 days. We compared this with our practice for the preceding year. Results: The numbers of filters inserted during the two time periods was similar, as were the numbers of retrieval attempts and the time scale at which they occurred. The rate of successful retrievals increased but not significantly. The major changes were better documentation of filter types and better clinical follow-up. After the change in practice, only one patient was lost to follow-up compared with six the preceding year. Conclusions: Although there was no significant improvement in retrieval rates, the proactive, radiology-led approach improved follow-up and documentation, ensuring that a clinical decision was made about how long the filter was required and whether retrieval should be attempted and ensuring that patients were not lost to follow-up.

  7. Technology assessment on a hydrogen fueled aircraft system; 1980 nendo suiso nenryo kokuki system ni kansuru technology assissment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-03-01

    This paper describes technology assessment on a hydrogen fueled aircraft system. Indispensable as technological assignments are structuring different safety systems including prevention of leakage and ignition, not to speak of developing an airframe structure that considers cryogenic and brittle nature of liquefied hydrogen. Operation related industries would be subjected to increased burdens, such as purchase and servicing of new implements and materials, but the liquefied hydrogen industry will have a chance of growing largely with wide repercussions. In the environmental aspect, the aircraft will have less CO and SOx emission in exhaust gas and lower noise than the conventional jet aircraft. Technological problems to be solved in the development include the safety of fuel tanks, safety assurance measures, and liquefied hydrogen of the required amount to be supplied easily and at low cost. To meet these requirements, noticeable progress is demanded in hydrogen manufacturing technologies. What is also required is explosion-proof safety that does not have to require crews to take special considerations in take-off and landing, not to speak of during flight. This also applies to fuel feeding and servicing on the ground. Considerations must be given that rise in operation cost should not be excessive. (NEDO)

  8. Life-cycle implications of hydrogen fuel cell electric vehicle technology for medium- and heavy-duty trucks

    Science.gov (United States)

    Lee, Dong-Yeon; Elgowainy, Amgad; Kotz, Andrew; Vijayagopal, Ram; Marcinkoski, Jason

    2018-07-01

    This study provides a comprehensive and up-to-date life-cycle comparison of hydrogen fuel cell electric trucks (FCETs) and their conventional diesel counterparts in terms of energy use and air emissions, based on the ensemble of well-established methods, high-fidelity vehicle dynamic simulations, and real-world vehicle test data. For the centralized steam methane reforming (SMR) pathway, hydrogen FCETs reduce life-cycle or well-to-wheel (WTW) petroleum energy use by more than 98% compared to their diesel counterparts. The reduction in WTW air emissions for gaseous hydrogen (G.H2) FCETs ranges from 20 to 45% for greenhouse gases, 37-65% for VOC, 49-77% for CO, 62-83% for NOx, 19-43% for PM10, and 27-44% for PM2.5, depending on vehicle weight classes and truck types. With the current U.S. average electricity generation mix, FCETs tend to create more WTW SOx emissions than their diesel counterparts, mainly because of the upstream emissions related to electricity use for hydrogen compression/liquefaction. Compared to G.H2, liquid hydrogen (L.H2) FCETs generally provide smaller WTW emissions reductions. For both G.H2 and L.H2 pathways for FCETs, because of electricity consumption for compression and liquefaction, spatio-temporal variations of electricity generation can affect the WTW results. FCETs retain the WTW emission reduction benefits, even when considering aggressive diesel engine efficiency improvement.

  9. Development of a market penetration forecasting model for Hydrogen Fuel Cell Vehicles considering infrastructure and cost reduction effects

    International Nuclear Information System (INIS)

    Park, Sang Yong; Kim, Jong Wook; Lee, Duk Hee

    2011-01-01

    In order to cope with climate change, the development and deployment of Hydrogen Fuel Cell Vehicles (HFCVs) is becoming more important. In this study, we developed a forecasting model for HFCVs based on the generalized Bass diffusion model and a simulation model using system dynamics. Through the developed model, we could forecast that the saturation of HFCVs in Korea can be moved up 12 years compared with the US. A sensitivity analysis on external variables such as price reduction rates of HFCVs and number of hydrogen refueling stations is also conducted. The results of this study can give insights on the effects of external variables on the market penetration of HFCVs, and the developed model can also be applied to other studies in analyzing the diffusion effects of HFCVs. - Highlights: → A forecasting model for HFCVs was developed using the generalized Bass diffusion model. → A simulation model using system dynamics was also developed. → The empirical study shows that the infrastructure is an important factor to the initial purchase. → The results of this study can promote research related to the diffusion of innovation.

  10. Techno-economic feasibility analysis of hydrogen fuel cell and solar photovoltaic hybrid renewable energy system for academic research building

    International Nuclear Information System (INIS)

    Singh, Anand; Baredar, Prashant; Gupta, Bhupendra

    2017-01-01

    Highlights: • A HFC and SPV HRES for stand-alone applications is proposed. • The FC program computes the optimum cost of HRES components. • HOMER pro software to calculate the optimum performance of HRES. - Abstract: A hydrogen fuel cell (HFC) and solar photovoltaic (SPV) hybrid renewable energy system (HRES) for stand-alone applications is proposed. This system arrangement of a hydrogen tank, battery, and an electrolyzer are used as like the energy storage. The economic viability of using HRES power to supply the electrical load demand of academic research building located at 23°12′N latitude and 77°24′E longitudes, India is examined. The fuzzy logic program computes the optimum value of capital and replacement cost of the components, which is then utilized in HOMER pro software to calculate the optimum performance of HRES. The results shows the HFC and battery bank are the most significant modules of the HRES to meet load demand at late night and early morning hours. The AC primary load consuming 20712.63 kWh/year out of total power generation of HRES which is 24570.72 kWh/year. The excess of electricity produced by HRES is 791.7709 kWh/year with the optimized cost of energy, unmet electrical load and capacity shortage of 0%.

  11. The performance of a grid-tied microgrid with hydrogen storage and a hydrogen fuel cell stack

    International Nuclear Information System (INIS)

    Zhang, Linfeng; Xiang, Jing

    2014-01-01

    Highlights: • Two microgrids with different structure are simulated. • Their performance are comprehensively evaluated and compared. • The one with DES and a FC stack has high environmental and quality indexes. - Abstract: In a heat-power system, the use of distributed energy generation and storage not only improves system’s efficiency and reliability but also reduce the emission. This paper is focused on the comprehensive performance evaluation of a grid-tied microgrid, which consists of a PV system, a hydrogen fuel cell stack, a PEM electrolyzer, and a hydrogen tank. Electricity and heat are generated in this system, to meet the local electric and heat demands. The surplus electricity can be stored as hydrogen, which is supplied to the fuel cell stack to generate heat and power as needed. The performance of the microgrid is comprehensively evaluated and is compared with another microgrid without a fuel cell stack. As a result, the emission and the service quality in the first system are higher than those in the second one. But they both have the same overall performance

  12. Overcoming the Range Limitation of Medium-Duty Battery Electric Vehicles through the use of Hydrogen Fuel-Cells

    Energy Technology Data Exchange (ETDEWEB)

    Wood, E.; Wang, L.; Gonder, J.; Ulsh, M.

    2013-10-01

    Battery electric vehicles possess great potential for decreasing lifecycle costs in medium-duty applications, a market segment currently dominated by internal combustion technology. Characterized by frequent repetition of similar routes and daily return to a central depot, medium-duty vocations are well positioned to leverage the low operating costs of battery electric vehicles. Unfortunately, the range limitation of commercially available battery electric vehicles acts as a barrier to widespread adoption. This paper describes the National Renewable Energy Laboratory's collaboration with the U.S. Department of Energy and industry partners to analyze the use of small hydrogen fuel-cell stacks to extend the range of battery electric vehicles as a means of improving utility, and presumably, increasing market adoption. This analysis employs real-world vocational data and near-term economic assumptions to (1) identify optimal component configurations for minimizing lifecycle costs, (2) benchmark economic performance relative to both battery electric and conventional powertrains, and (3) understand how the optimal design and its competitiveness change with respect to duty cycle and economic climate. It is found that small fuel-cell power units provide extended range at significantly lower capital and lifecycle costs than additional battery capacity alone. And while fuel-cell range-extended vehicles are not deemed economically competitive with conventional vehicles given present-day economic conditions, this paper identifies potential future scenarios where cost equivalency is achieved.

  13. Audit of the use of IVC filters in the UK: experience from three centres over 12 years

    Energy Technology Data Exchange (ETDEWEB)

    Hammond, C.J. [Leeds General Infirmary, Leeds (United Kingdom)], E-mail: chris.hammond@doctors.org.uk; Bakshi, D.R. [Royal Liverpool University Hospital, Liverpool (United Kingdom); Currie, R.J. [Royal Devon and Exeter Hospital, Exeter (United Kingdom); Patel, J.V. [Leeds General Infirmary, Leeds (United Kingdom); Kinsella, D. [Royal Devon and Exeter Hospital, Exeter (United Kingdom); McWilliams, R.G. [Royal Liverpool University Hospital, Liverpool (United Kingdom); Watkinson, A. [Royal Devon and Exeter Hospital, Exeter (United Kingdom); Nicholson, A.A. [Leeds General Infirmary, Leeds (United Kingdom)

    2009-05-15

    Aim: To audit the use of inferior vena cava (IVC) filter insertions at three UK centres over 12 years to assess whether trends in filter use in the UK mirrored those seen elsewhere. Materials and methods: Radiology department databases were interrogated for IVC filter insertions and removals between 1994 and 2006. Reports for these interventions, along with prior and subsequent imaging reports, were analysed. Follow-up data were obtained when available. Results: Five hundred and sixteen filters were placed with a significant year-on-year trend towards increasing use. Fifty-seven percent of filters placed were for absolute indications and 37% for relative indications. The filters were used for prophylaxis in 6% of patients in the absence of proven pulmonary embolism (PE) or deep vein thrombosis (DVT). A retrievable filter was used in 74% of cases with retrieval attempted in 40% of these and no evidence of an increasing rate of retrieval over time. A significant complication related to insertion or retrieval was encountered in 0.4 and 1% of procedures, respectively. Mean 24 h and 30 day mortalities were 1 and 8%, respectively. There was an absence of organized follow-up at all three centres. Conclusion: IVC filter use in the UK is increasing. The use of retrievable filters has not resulted in increased filter retrieval. Filter insertion and retrieval is associated with a low risk of significant complication, but lack of systematic follow-up limits conclusions regarding safety and efficacy.

  14. Clinical significance of determination of serum collagen type IV (IV-C) and transforming growth factor beta1(TGF-β1) levels in patients with diabetic nephropathy

    International Nuclear Information System (INIS)

    Xie Hongfang; Peng Liang

    2006-01-01

    Objective: To investigate the clinical significance of determination of serum collagen type IV (IV-C) and transforming growth factor beta 1 (TGF-β 1 ) levels in patients with diabetic nephropathy. Methods: Serum IV-C levels ( with RIA) and TGF-β 1 levels (with ELISA) were determined in 30 controls and 105 patients with type II diabetis mellitus (45 with diabetic nephropathy and 60 without nephropathy). Results: The serum levels of IV-C and TGF-β 1 in diabetic patients with nephropathy were significantly higher than those in controls (P 0.05). Conclusion: Serum IV-C and TGF-β 1 , levels increased gradually as the diabetic nephropathy got more severe, they could be used as sensitive markers for early diagnosis of development of diabetic nephropathy. (authors)

  15. Perforation of the IVC: Rule Rather Than Exception After Longer Indwelling Times for the Günther Tulip and Celect Retrievable Filters

    International Nuclear Information System (INIS)

    Durack, Jeremy C.; Westphalen, Antonio C.; Kekulawela, Stephanie; Bhanu, Shiv B.; Avrin, David E.; Gordon, Roy L.; Kerlan, Robert K.

    2012-01-01

    Purpose: This study was designed to assess the incidence, magnitude, and impact upon retrievability of vena caval perforation by Günther Tulip and Celect conical inferior vena cava (IVC) filters on computed tomographic (CT) imaging. Methods: Günther Tulip and Celect IVC filters placed between July 2007 and May 2009 were identified from medical records. Of 272 IVC filters placed, 50 (23 Günther Tulip, 46%; 27 Celect, 54%) were retrospectively assessed on follow-up abdominal CT scans performed for reasons unrelated to the filter. Computed tomography scans were examined for evidence of filter perforation through the vena caval wall, tilt, or pericaval tissue injury. Procedure records were reviewed to determine whether IVC filter retrieval was attempted and successful. Results: Perforation of at least one filter component through the IVC was observed in 43 of 50 (86%) filters on CT scans obtained between 1 and 880 days after filter placement. All filters imaged after 71 days showed some degree of vena caval perforation, often as a progressive process. Filter tilt was seen in 20 of 50 (40%) filters, and all tilted filters also demonstrated vena caval perforation. Transjugular removal was attempted in 12 of 50 (24%) filters and was successful in 11 of 12 (92%). Conclusions: Longer indwelling times usually result in vena caval perforation by retrievable Günther Tulip and Celect IVC filters. Although infrequently reported in the literature, clinical sequelae from IVC filter components breaching the vena cava can be significant. We advocate filter retrieval as early as clinically indicated and increased attention to the appearance of IVC filters on all follow-up imaging studies.

  16. Perforation of the IVC: rule rather than exception after longer indwelling times for the Günther Tulip and Celect retrievable filters.

    Science.gov (United States)

    Durack, Jeremy C; Westphalen, Antonio C; Kekulawela, Stephanie; Bhanu, Shiv B; Avrin, David E; Gordon, Roy L; Kerlan, Robert K

    2012-04-01

    This study was designed to assess the incidence, magnitude, and impact upon retrievability of vena caval perforation by Günther Tulip and Celect conical inferior vena cava (IVC) filters on computed tomographic (CT) imaging. Günther Tulip and Celect IVC filters placed between July 2007 and May 2009 were identified from medical records. Of 272 IVC filters placed, 50 (23 Günther Tulip, 46%; 27 Celect, 54%) were retrospectively assessed on follow-up abdominal CT scans performed for reasons unrelated to the filter. Computed tomography scans were examined for evidence of filter perforation through the vena caval wall, tilt, or pericaval tissue injury. Procedure records were reviewed to determine whether IVC filter retrieval was attempted and successful. Perforation of at least one filter component through the IVC was observed in 43 of 50 (86%) filters on CT scans obtained between 1 and 880 days after filter placement. All filters imaged after 71 days showed some degree of vena caval perforation, often as a progressive process. Filter tilt was seen in 20 of 50 (40%) filters, and all tilted filters also demonstrated vena caval perforation. Transjugular removal was attempted in 12 of 50 (24%) filters and was successful in 11 of 12 (92%). Longer indwelling times usually result in vena caval perforation by retrievable Günther Tulip and Celect IVC filters. Although infrequently reported in the literature, clinical sequelae from IVC filter components breaching the vena cava can be significant. We advocate filter retrieval as early as clinically indicated and increased attention to the appearance of IVC filters on all follow-up imaging studies.

  17. Management of IVC Injury: Repair or Ligation? A Propensity Score Matching Analysis Using the National Trauma Data Bank.

    Science.gov (United States)

    Matsumoto, Shokei; Jung, Kyoungwon; Smith, Alan; Coimbra, Raul

    2018-03-01

    Ligation can be used as part of damage-control operations under critical conditions after IVC injury. Inferior vena cava ligation could potentially yield greater survival benefit compared with repair after injury. We hypothesized that ligation significantly improves outcomes compared with repair. The National Trauma Data Bank dataset for 2007-2014 was reviewed. Eligible patients included those sustaining IVC injury who underwent surgical ligation or repair. Data on demographics, outcomes, and complications were collected. Comparative analysis of demographic characteristics, complications and outcomes were performed. There were 4,865 patients identified in the National Trauma Data Bank with IVC injury. A total of 1,316 patients met inclusion criteria. Four hundred and forty-seven patients (34.0%) underwent ligation and 869 (66.0%) underwent repair. Before matching, the ligation group was sicker than the repair group and the in-hospital mortality was significantly higher in the ligation group (43.8% vs 36.2%; odds ratio [OR] 1.37; 95% CI 1.09 to 1.73). One to one propensity score matching generated 310 pairs. After propensity score matching, in-hospital mortality was similar (41.3% vs 39.0%; OR 1.10; 95% CI 0.80 to 1.52). However, IVC ligation was associated with significantly higher complication rates of extremity compartment syndrome (OR 5.23; 95% CI 1.50 to 18.24), pneumonia (OR 1.76; 95% CI 1.08 to 2.86), deep venous thrombosis (OR 2.83 95% CI 1.70 to 4.73), pulmonary embolism (OR 3.63; 95% CI 1.18 to 11.17), and longer hospital length of stay (17.0 days [interquartile range 1.0 to 35.0 days] vs 9.0 days [interquartile range 1.0 to 22.0 days]; p = 0.002). Inferior vena cava ligation is not superior to repair in terms of decreasing mortality in patients with IVC injury, but it is associated with higher complication rates and hospital LOS. Copyright © 2018 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  18. The Effect of Converting to a U.S. Hydrogen Fuel Cell Vehicle Fleet on Emissions and Energy Use

    Science.gov (United States)

    Colella, W. G.; Jacobson, M. Z.; Golden, D. M.

    2004-12-01

    This study analyzes the potential change in emissions and energy use from replacing fossil-fuel based vehicles with hydrogen fuel cell vehicles. This study examines three different hydrogen production scenarios to determine their resultant emissions and energy usage: hydrogen produced via 1) steam reforming of methane, 2) coal gasification, or 3) wind electrolysis. The atmospheric model simulations require two primary sets of data: the actual emissions associated with hydrogen fuel production and use, and the corresponding reduction in emissions associated with reducing fossil fuel use. The net change in emissions is derived using 1) the U.S. EPA's National Emission Inventory (NEI) that incorporates several hundred categories of on-road vehicles and 2) a Process Chain Analysis (PCA) for the different hydrogen production scenarios. NEI: The quantity of hydrogen-related emission is ultimately a function of the projected hydrogen consumption in on-road vehicles. Data for hydrogen consumption from on-road vehicles was derived from the number of miles driven in each U.S. county based on 1999 NEI data, the average fleet mileage of all on-road vehicles, the average gasoline vehicle efficiency, and the efficiency of advanced 2004 fuel cell vehicles. PCA: PCA involves energy and mass balance calculations around the fuel extraction, production, transport, storage, and delivery processes. PCA was used to examine three different hydrogen production scenarios: In the first scenario, hydrogen is derived from natural gas, which is extracted from gas fields, stored, chemically processed, and transmitted through pipelines to distributed fuel processing units. The fuel processing units, situated in similar locations as gasoline refueling stations, convert natural gas to hydrogen via a combination of steam reforming and fuel oxidation. Purified hydrogen is compressed for use onboard fuel cell vehicles. In the second scenario, hydrogen is derived from coal, which is extracted from

  19. Hydrogen Fueled Hybrid Solid Oxide Fuel Cell-Gas Turbine (SOFC-GT) System for Long-Haul Rail Application

    Science.gov (United States)

    Chow, Justin Jeff

    Freight movement of goods is the artery for America's economic health. Long-haul rail is the premier mode of transport on a ton-mile basis. Concerns regarding greenhouse gas and criteria pollutant emissions, however, have motivated the creation of annually increasing locomotive emissions standards. Health issues from diesel particulate matter, especially near rail yards, have also been on the rise. These factors and the potential to raise conventional diesel-electric locomotive performance warrants the investigation of using future fuels in a more efficient system for locomotive application. This research evaluates the dynamic performance of a Solid Oxide Fuel Cell-Gas Turbine (SOFC-GT) Hybrid system operating on hydrogen fuel to power a locomotive over a rail path starting from the Port of Los Angeles and ending in the City of Barstow. Physical constraints, representative locomotive operation logic, and basic design are used from a previous feasibility study and simulations are performed in the MATLAB Simulink environment. In-house controls are adapted to and expanded upon. Results indicate high fuel-to-electricity efficiencies of at least 54% compared to a conventional diesel-electric locomotive efficiency of 35%. Incorporation of properly calibrated feedback and feed-forward controls enables substantial load following of difficult transients that result from train kinematics while maintaining turbomachinery operating requirements and suppressing thermal stresses in the fuel cell stack. The power split between the SOFC and gas turbine is deduced to be a deterministic factor in the balance between capital and operational costs. Using hydrogen results in no emissions if renewable and offers a potential of 24.2% fuel energy savings for the rail industry.

  20. CFD analysis of bubble hydrodynamics in a fuel reactor for a hydrogen-fueled chemical looping combustion system

    International Nuclear Information System (INIS)

    Harichandan, Atal Bihari; Shamim, Tariq

    2014-01-01

    Highlights: • Computational study of the fuel reactor of chemical looping combustion technology. • The results yield better understanding of the bubble hydrodynamics in fuel reactor. • Increasing the reactor bed length increases the conversion rate. • Small oxygen carrier particles improves the conversion rate. - Abstract: This study investigates the temporal development of bubble hydrodynamics in the fuel reactor of a hydrogen-fueled chemical looping combustion (CLC) system by using a computational model. The model also investigates the molar fraction of products in gas and solid phases. The study assists in developing a better understanding of the CLC process, which has many advantages such as being a potentially promising candidate for an efficient carbon dioxide capture technology. The study employs the kinetic theory of granular flow. The reactive fluid dynamic system of the fuel reactor is customized by incorporating the kinetics of an oxygen carrier reduction into a commercial computational fluid dynamics (CFD) code. An Eulerian multiphase treatment is used to describe the continuum two-fluid model for both gas and solid phases. CaSO 4 and H 2 are used as an oxygen carrier and a fuel, respectively. The computational results are validated with the experimental and numerical results available in the open literature. The CFD simulations are found to capture the features of the bubble formation, rise and burst in unsteady and quasi-steady states very well. The results show a significant increase in the conversion rate with higher dense bed height, lower bed width, higher free board height and smaller oxygen carrier particles which upsurge an overall performance of the CLC plant

  1. Cryogenic Hydrogen Fuel for Controlled Inertial Confinement Fusion (Cryogenic Target Factory Concept Based on FST-Layering Method)

    Science.gov (United States)

    Aleksandrova, I. V.; Koresheva, E. R.; Koshelev, I. E.; Krokhin, O. N.; Nikitenko, A. I.; Osipov, I. E.

    2017-12-01

    A central element of a power plant based on inertial confinement fusion (ICF) is a target with cryogenic hydrogen fuel that should be delivered to the center of a reactor chamber with a high accuracy and repetition rate. Therefore, a cryogenic target factory (CTF) is an integral part of any ICF reactor. A promising way to solve this problem consists in the FST layering method developed at the Lebedev Physical Institute (LPI). This method (rapid fuel layering inside moving free-standing targets) is unique, having no analogs in the world. The further development of FST-layering technologies is implemented in the scope of the LPI program for the creation of a modular CTF and commercialization of the obtained results. In this report, we discuss our concept of CTF (CTF-LPI) that exhibits the following distinctive features: using a FST-layering technology for the elaboration of an in-line production of cryogenic targets, using an effect of quantum levitation of high-temperature superconductors (HTSCs) in magnetic field for noncontacting manipulation, transport, and positioning of the free-standing cryogenic targets, as well as in using a Fourier holography technique for an on-line characterization and tracking of the targets flying into the reactor chamber. The results of original experimental and theoretical investigations performed at LPI indicate that the existing and developing target fabrication capabilities and technologies can be applied to ICF target production. The unique scientific, engineering, and technological base developed in Russia at LPI allows one to make a CTFLPI prototype for mass production of targets and delivery thereof at the required velocity into the ICF reactor chamber.

  2. Platinum supported on titanium–ruthenium oxide is a remarkably stable electrocatayst for hydrogen fuel cell vehicles

    Science.gov (United States)

    Parrondo, Javier; Han, Taehee; Niangar, Ellazar; Wang, Chunmei; Dale, Nilesh; Adjemian, Kev; Ramani, Vijay

    2014-01-01

    We report a unique and highly stable electrocatalyst—platinum (Pt) supported on titanium–ruthenium oxide (TRO)—for hydrogen fuel cell vehicles. The Pt/TRO electrocatalyst was exposed to stringent accelerated test protocols designed to induce degradation and failure mechanisms identical to those seen during extended normal operation of a fuel cell automobile—namely, support corrosion during vehicle startup and shutdown, and platinum dissolution during vehicle acceleration and deceleration. These experiments were performed both ex situ (on supports and catalysts deposited onto a glassy carbon rotating disk electrode) and in situ (in a membrane electrode assembly). The Pt/TRO was compared against a state-of-the-art benchmark catalyst—Pt supported on high surface-area carbon (Pt/HSAC). In ex situ tests, Pt/TRO lost only 18% of its initial oxygen reduction reaction mass activity and 3% of its oxygen reduction reaction-specific activity, whereas the corresponding losses for Pt/HSAC were 52% and 22%. In in situ-accelerated degradation tests performed on membrane electrode assemblies, the loss in cell voltage at 1 A · cm−2 at 100% RH was a negligible 15 mV for Pt/TRO, whereas the loss was too high to permit operation at 1 A · cm−2 for Pt/HSAC. We clearly show that electrocatalyst support corrosion induced during fuel cell startup and shutdown is a far more potent failure mode than platinum dissolution during fuel cell operation. Hence, we posit that the need for a highly stable support (such as TRO) is paramount. Finally, we demonstrate that the corrosion of carbon present in the gas diffusion layer of the fuel cell is only of minor concern. PMID:24367118

  3. Platinum supported on titanium-ruthenium oxide is a remarkably stable electrocatayst for hydrogen fuel cell vehicles.

    Science.gov (United States)

    Parrondo, Javier; Han, Taehee; Niangar, Ellazar; Wang, Chunmei; Dale, Nilesh; Adjemian, Kev; Ramani, Vijay

    2014-01-07

    We report a unique and highly stable electrocatalyst-platinum (Pt) supported on titanium-ruthenium oxide (TRO)-for hydrogen fuel cell vehicles. The Pt/TRO electrocatalyst was exposed to stringent accelerated test protocols designed to induce degradation and failure mechanisms identical to those seen during extended normal operation of a fuel cell automobile-namely, support corrosion during vehicle startup and shutdown, and platinum dissolution during vehicle acceleration and deceleration. These experiments were performed both ex situ (on supports and catalysts deposited onto a glassy carbon rotating disk electrode) and in situ (in a membrane electrode assembly). The Pt/TRO was compared against a state-of-the-art benchmark catalyst-Pt supported on high surface-area carbon (Pt/HSAC). In ex situ tests, Pt/TRO lost only 18% of its initial oxygen reduction reaction mass activity and 3% of its oxygen reduction reaction-specific activity, whereas the corresponding losses for Pt/HSAC were 52% and 22%. In in situ-accelerated degradation tests performed on membrane electrode assemblies, the loss in cell voltage at 1 A · cm(-2) at 100% RH was a negligible 15 mV for Pt/TRO, whereas the loss was too high to permit operation at 1 A · cm(-2) for Pt/HSAC. We clearly show that electrocatalyst support corrosion induced during fuel cell startup and shutdown is a far more potent failure mode than platinum dissolution during fuel cell operation. Hence, we posit that the need for a highly stable support (such as TRO) is paramount. Finally, we demonstrate that the corrosion of carbon present in the gas diffusion layer of the fuel cell is only of minor concern.

  4. Günther Tulip and Celect IVC filters in multiple-trauma patients.

    Science.gov (United States)

    Rosenthal, David; Kochupura, Paul V; Wellons, Eric D; Burkett, Allison B; Methodius-Rayford, Walaya C

    2009-08-01

    To evaluate results with the retrievable Günther Tulip (GT) and Celect inferior vena cava filters (IVCFs) placed at the intensive care unit (ICU) bedside under "real-time" intravascular ultrasound (IVUS) guidance in multiple-trauma patients. Between December 2004 and December 2008, 187 multiple-trauma patients (109 men; mean age 44+/-2 years, range 17-71) with contraindications to low-dose anticoagulation therapy or sequential compression devices had Günther Tulip (n = 97) or Celect (n = 90) retrievable IVCFs placed under real-time IVUS guidance. Günther Tulip filters were inserted using a "double-puncture" technique. The Celect IVCFs were placed with a simplified single-puncture technique in which the filter introducer sheath was advanced until the radiopaque tip "covered" the IVUS image of the renal vein, indicating that the filter sheath was in position for filter deployment. The 2 filter groups were compared on the endpoints of technical implantation success, retrievability, prevention of PE, and procedure-related deep vein thrombosis (DVT). As verified by abdominal radiography, 93.1% (174/187) of IVCFs were placed without complications; 6 IVCFs (all GT; p = 0.03 versus Celect) were misplaced in the iliac vein but uneventfully retrieved and replaced in the IVC within 24 hours. Two insertion site femoral vein DVTs (both in the dual puncture group; p>0.2) and 5 groin hematomas occurred during follow-up. GT filters were in place a mean of 107 days and Celect 97 days. In this time, 2 pulmonary embolisms occurred (1 in each group; p>0.2). Of the 115 filters scheduled for retrieval (50 Günther Tulip, 65 Celect), 33 (23 Günther Tulip, 10 Celect) could not be retrieved (p = 0.0004). Vena cavography identified filter tilting (>20 degrees ) in 21 cases (15 GT, 6 Celect), while 12 filters (8 GT, 4 Celect) had extended indwell times (mean 187 days) and excessive tissue ingrowth covering the retrieval hook. Subjectively, the Celect filters were clinically "easier" to

  5. Murine norovirus detection in the exhaust air of IVCs is more sensitive than serological analysis of soiled bedding sentinels.

    Science.gov (United States)

    Zorn, Julia; Ritter, Bärbel; Miller, Manuel; Kraus, Monika; Northrup, Emily; Brielmeier, Markus

    2017-06-01

    One limitation to housing rodents in individually ventilated cages (IVCs) is the ineffectiveness of traditional health monitoring programs that test soiled bedding sentinels every quarter. Aerogen transmission does not occur with this method. Moreover, the transmission of numerous pathogens in bedding is uncertain, and sentinel susceptibility to various pathogens varies. A novel method using particle collection from samples of exhaust air was developed in this study which was also systematically compared with routine health monitoring using soiled bedding sentinels. We used our method to screen these samples for the presence of murine norovirus (MNV), a mouse pathogen highly prevalent in laboratory animal facilities. Exhaust air particles from prefilters of IVC racks with known MNV prevalence were tested by quantitative reverse transcription polymerase chain reaction (RT-qPCR). MNV was detected in exhaust air as early as one week with one MNV-positive cage per rack, while sentinels discharged MNV RNA without seroconverting. MNV was reliably and repeatedly detected in particles collected from samples of exhaust air in all seven of the three-month sampling rounds, with increasing MNV prevalence, while sentinels only seroconverted in one round. Under field conditions, routine soiled bedding sentinel health monitoring in our animal facility failed to identify 67% ( n = 85) of positive samples by RT-qPCR of exhaust air particles. Thus, this method proved to be highly sensitive and superior to soiled bedding sentinels in the reliable detection of MNV. These results represent a major breakthrough in hygiene monitoring of rodent IVC systems and contribute to the 3R principles by reducing the number of animals used and by improving experimental conditions.

  6. Hydrogen fuel - Universal energy

    Science.gov (United States)

    Prince, A. G.; Burg, J. A.

    The technology for the production, storage, transmission, and consumption of hydrogen as a fuel is surveyed, with the physical and chemical properties of hydrogen examined as they affect its use as a fuel. Sources of hydrogen production are described including synthesis from coal or natural gas, biomass conversion, thermochemical decomposition of water, and electrolysis of water, of these only electrolysis is considered economicially and technologically feasible in the near future. Methods of production of the large quantities of electricity required for the electrolysis of sea water are explored: fossil fuels, hydroelectric plants, nuclear fission, solar energy, wind power, geothermal energy, tidal power, wave motion, electrochemical concentration cells, and finally ocean thermal energy conversion (OTEC). The wind power and OTEC are considered in detail as the most feasible approaches. Techniques for transmission (by railcar or pipeline), storage (as liquid in underwater or underground tanks, as granular metal hydride, or as cryogenic liquid), and consumption (in fuel cells in conventional power plants, for home usage, for industrial furnaces, and for cars and aircraft) are analyzed. The safety problems of hydrogen as a universal fuel are discussed, noting that they are no greater than those for conventional fuels.

  7. Hydrogen: Fueling the Future

    International Nuclear Information System (INIS)

    Leisch, Jennifer

    2007-01-01

    As our dependence on foreign oil increases and concerns about global climate change rise, the need to develop sustainable energy technologies is becoming increasingly significant. Worldwide energy consumption is expected to double by the year 2050, as will carbon emissions along with it. This increase in emissions is a product of an ever-increasing demand for energy, and a corresponding rise in the combustion of carbon containing fossil fuels such as coal, petroleum, and natural gas. Undisputable scientific evidence indicates significant changes in the global climate have occurred in recent years. Impacts of climate change and the resulting atmospheric warming are extensive, and know no political or geographic boundaries. These far-reaching effects will be manifested as environmental, economic, socioeconomic, and geopolitical issues. Offsetting the projected increase in fossil energy use with renewable energy production will require large increases in renewable energy systems, as well as the ability to store and transport clean domestic fuels. Storage and transport of electricity generated from intermittent resources such as wind and solar is central to the widespread use of renewable energy technologies. Hydrogen created from water electrolysis is an option for energy storage and transport, and represents a pollution-free source of fuel when generated using renewable electricity. The conversion of chemical to electrical energy using fuel cells provides a high efficiency, carbon-free power source. Hydrogen serves to blur the line between stationary and mobile power applications, as it can be used as both a transportation fuel and for stationary electricity generation, with the possibility of a distributed generation energy infrastructure. Hydrogen and fuel cell technologies will be presented as possible pollution-free solutions to present and future energy concerns. Recent hydrogen-related research at SLAC in hydrogen production, fuel cell catalysis, and hydrogen storage will be highlighted in this seminar.

  8. Hydrogen fuel. Uses

    International Nuclear Information System (INIS)

    Darkrim-Lamari, F.; Malbrunot, P.

    2006-01-01

    Hydrogen is a very energetic fuel which can be used in combustion to generate heat and mechanical energy or which can be used to generate electricity and heat through an electrochemical reaction with oxygen. This article deals with the energy conversion, the availability and safety problems linked with the use of hydrogen, and with the socio-economical consequences of a generalized use of hydrogen: 1 - hydrogen energy conversion: hydrogen engines, aerospace applications, fuel cells (principle, different types, domains of application); 2 - hydrogen energy availability: transport and storage (gas pipelines, liquid hydrogen, adsorbed and absorbed hydrogen in solid materials), service stations; 3 - hazards and safety: flammability, explosibility, storage and transport safety, standards and regulations; 4 - hydrogen economy; 5 - conclusion. (J.S.)

  9. Hydrogen Fuel Cell Vehicles

    OpenAIRE

    Anton Francesch, Judit

    1992-01-01

    Hydrogen is an especially attractive transportation fuel. It is the least polluting fuel available, and can be produced anywhere there is water and a clean source of electricity. A fuel cycle in which hydrogen is produced by solar-electrolysis of water, or by gasification of renewably grown biomass, and then used in a fuel-cell powered electric-motor vehicle (FCEV), would produce little or no local, regional, or global pollution. Hydrogen FCEVs would combine the best features of bat...

  10. Membranous IVC Obstruction Presenting with Antegrade/Retrograde Respiratory Flow in the Intrahepatic Segment in Doppler Imaging and Prostatic and Urethral Congestion

    International Nuclear Information System (INIS)

    Sood, Dinesh; Mistry, Kewal A.; Chadha, Veenal; Sharma, Sarthak; Morey, Parikshit D.; Suthar, Pokhraj P.; Patel, Dhruv G.

    2015-01-01

    Obstruction of the inferior vena cava (IVC) is infrequent, membranous obstruction of the IVC (MOIVC) being one of its rare causes. Early diagnosis is important, as it can lead to hepatic congestion, cirrhosis and Budd-Chiari syndrome (BCS) and can predispose to development of hepatocellular carcinoma (HCC) in severe cases. We report a case of membranous IVC obstruction at the junction of hepatic and suprahepatic segments in a young male with extensive collateralization and venous aneurysms. Unique findings involved antegrade and retrograde flow during respiration in the upper part of intrahepatic IVC proximal to a large collateral vein as well as prostatic and urethral congestion leading to intermittent urinary hesitancy, which have not yet been described in such cases. MOIVC is a rare cause of IVC obstruction with typical radiological features. Early diagnosis and management is required due to risk of cirrhosis and HCC. Antegrade and retrograde flow may be seen in incomplete MOIVC above the level of a large collateral vein and it may lead to prostatic and urethral congestion

  11. Techno-economic and behavioural analysis of battery electric, hydrogen fuel cell and hybrid vehicles in a future sustainable road transport system in the UK

    International Nuclear Information System (INIS)

    Offer, G.J.; Contestabile, M.; Howey, D.A.; Clague, R.; Brandon, N.P.

    2011-01-01

    This paper conducts a techno-economic study on hydrogen Fuel Cell Electric Vehicles (FCV), Battery Electric Vehicles (BEV) and hydrogen Fuel Cell plug-in Hybrid Electric Vehicles (FCHEV) in the UK using cost predictions for 2030. The study includes an analysis of data on distance currently travelled by private car users daily in the UK. Results show that there may be diminishing economic returns for Plug-in Hybrid Electric Vehicles (PHEV) with battery sizes above 20 kWh, and the optimum size for a PHEV battery is between 5 and 15 kWh. Differences in behaviour as a function of vehicle size are demonstrated, which decreases the percentage of miles that can be economically driven using electricity for a larger vehicle. Decreasing carbon dioxide emissions from electricity generation by 80% favours larger optimum battery sizes as long as carbon is priced, and will reduce emissions considerably. However, the model does not take into account reductions in carbon dioxide emissions from hydrogen generation, assuming hydrogen will still be produced from steam reforming methane in 2030. - Research highlights: → Report diminishing returns for plug-in hybrids with battery sizes above 20 kWh. → The optimum size for a PHEV battery is between 5 and 15 kWh. → Current behaviour decreases percentage electric only miles for larger vehicles. → Low carbon electricity favours larger battery sizes as long as carbon is priced. → Reinforces that the FCHEV is a cheaper option than conventional ICE vehicles in 2030.

  12. Techno-economic and behavioural analysis of battery electric, hydrogen fuel cell and hybrid vehicles in a future sustainable road transport system in the UK

    Energy Technology Data Exchange (ETDEWEB)

    Offer, G.J., E-mail: gregory.offer@imperial.ac.u [Department Earth Science Engineering, Imperial College London, SW7 2AZ London (United Kingdom); Contestabile, M. [Centre for Environmental Policy, Imperial College London, SW7 2AZ (United Kingdom); Howey, D.A. [Department of Electrical and Electronic Engineering, Imperial College London, SW7 2AZ (United Kingdom); Clague, R. [Energy Futures Lab, Imperial College London, SW7 2AZ (United Kingdom); Brandon, N.P. [Department Earth Science Engineering, Imperial College London, SW7 2AZ London (United Kingdom)

    2011-04-15

    This paper conducts a techno-economic study on hydrogen Fuel Cell Electric Vehicles (FCV), Battery Electric Vehicles (BEV) and hydrogen Fuel Cell plug-in Hybrid Electric Vehicles (FCHEV) in the UK using cost predictions for 2030. The study includes an analysis of data on distance currently travelled by private car users daily in the UK. Results show that there may be diminishing economic returns for Plug-in Hybrid Electric Vehicles (PHEV) with battery sizes above 20 kWh, and the optimum size for a PHEV battery is between 5 and 15 kWh. Differences in behaviour as a function of vehicle size are demonstrated, which decreases the percentage of miles that can be economically driven using electricity for a larger vehicle. Decreasing carbon dioxide emissions from electricity generation by 80% favours larger optimum battery sizes as long as carbon is priced, and will reduce emissions considerably. However, the model does not take into account reductions in carbon dioxide emissions from hydrogen generation, assuming hydrogen will still be produced from steam reforming methane in 2030. - Research highlights: {yields} Report diminishing returns for plug-in hybrids with battery sizes above 20 kWh. {yields} The optimum size for a PHEV battery is between 5 and 15 kWh. {yields} Current behaviour decreases percentage electric only miles for larger vehicles. {yields} Low carbon electricity favours larger battery sizes as long as carbon is priced. {yields} Reinforces that the FCHEV is a cheaper option than conventional ICE vehicles in 2030.

  13. Requirements for low-cost electricity and hydrogen fuel production from multiunit inertial fusion energy plants with a shared driver and target factory

    International Nuclear Information System (INIS)

    Logan, G.B.; Moir, R.W.; Hoffmman, M.A.

    1995-01-01

    The economy of scale for multiunit inertial fusion energy (IFE) power plants is explored based on the molten salt HYLIFE-II fusion chamber concept, for the purpose of producing lower cost electricity and hydrogen fuel. The cost of electricity (CoE) is minimized with a new IFE systems code IFEFUEL5 for a matrix of plant cases with one to eight fusion chambers of 250 to 2000-MW (electric) net output each, sharing a common heavy-ion driver and target factory. Improvements to previous HYLIFE-II models include a recirculating induction linac driver optimized as a function of driver energy and rep-rate (average driver power), inclusion of beam switchyard costs, a fusion chamber cost scaling dependence on both thermal power and fusion yield, and a more accurate bypass pump power scaling with chamber rep-rate. A CoE less than 3 cents/kW(electric)-h is found for plant outputs greater than 2 GW(electric), allowing hydrogen fuel production by wafer electrolysis to provide lower fuel cost per mile for higher efficiency hydrogen engines compared with gasoline engines. These multiunit, multi-GW(electric) IFE plants allow staged utility plant deployment, lower optimum chamber rep-rates, less sensitivity to driver and target fabrication costs, and a CoE possibly lower than future fission, fossil, and solar competitors. 37 refs., 12 figs., 4 tabs

  14. Virulence of viral hemorrhagic septicemia virus (VHSV) genotypes Ia, IVa, IVb, and IVc in five fish species.

    Science.gov (United States)

    Emmenegger, Eveline J.; Moon, Chang Hoon; Hershberger, Paul K.; Kurath, Gael

    2013-01-01

    The susceptibility of yellow perch Perca flavescens, rainbow trout Oncorhynchus mykiss, Chinook salmon O. tshawytscha, koi Cyprinus carpio koi, and Pacific herring Clupea pallasii to 4 strains of viral hemorrhagic septicemia virus (VHSV) was assessed. Fish were challenged via intraperitoneal injection with high (1 × 106 plaque-forming units, PFU) and low (1 × 103 PFU) doses of a European strain (genotype Ia), and North American strains from the West coast (genotype IVa), Great Lakes (genotype IVb), and the East coast (genotype IVc). Pacific herring were exposed to the same VHSV strains, but at a single dose of 5 × 103 PFU ml-1 by immersion in static seawater. Overall, yellow perch were the most susceptible, with cumulative percent mortality (CPM) ranging from 84 to 100%, and 30 to 93% in fish injected with high or low doses of virus, respectively. Rainbow trout and Chinook salmon experienced higher mortalities (47 to 98% CPM) after exposure to strain Ia than to the other virus genotypes. Pacific herring were most susceptible to strain IVa with an average CPM of 80% and moderately susceptible (42 to 52% CPM) to the other genotypes. Koi had very low susceptibility (≤5.0% CPM) to all 4 VHSV strains. Fish tested at 7 d post challenge were positive for all virus strains, with yellow perch having the highest prevalence and concentrations of virus, and koi the lowest. While genotype Ia had higher virulence in salmonid species, there was little difference in virulence or host-specificity between isolates from subtypes IVa, IVb, and IVc.  

  15. Comparative requirements for electric energy for production of hydrogen fuel and/or recharging of battery electric automobile fleets in New Zealand and the United States

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, Paul [Stanford University, Stanford, CA 94305 (United States); Leaver, Jonathan D. [Department of Civil Engineering, Unitec NZ, Auckland 1142 (New Zealand)

    2010-10-15

    Within the current outlook for sustainable electric energy supply with concomitant reduction in emission of greenhouse gases, accelerated attention is focusing on the long-term development of hydrogen fuel cell and all-electric battery vehicles to provide alternative fuels to replace petroleum-derived fuels for automotive national fleets. The potential varies significantly between large industrially developed nations and smaller industrially developing nations. The requirement for additional electric energy supply from low-specific energy renewable resources and high-specific energy nuclear resources depends strongly on individual national economic, environmental, and political factors. Analysis of the additional electric energy supply required for the two potential large-scale technologies for fueling future national transportation sectors is compared for a large Organization for Economic Co-operation and Development (OECD) nation (USA) with a small OECD nation (New Zealand), normalized on a per-capita basis. (author)

  16. U.S. Department of Energy FreedomCar & Vehicle Technologies Program CARB Executive Order Exemption Process for a Hydrogen-fueled Internal Combustion engine Vehicle -- Status Report

    Energy Technology Data Exchange (ETDEWEB)

    2008-04-01

    The CARB Executive Order Exemption Process for a Hydrogen-fueled Internal Combustion Engine Vehicle was undertaken to define the requirements to achieve a California Air Resource Board Executive Order for a hydrogenfueled vehicle retrofit kit. A 2005 to 2006 General Motors Company Sierra/Chevrolet Silverado 1500HD pickup was assumed to be the build-from vehicle for the retrofit kit. The emissions demonstration was determined not to pose a significant hurdle due to the non-hydrocarbon-based fuel and lean-burn operation. However, significant work was determined to be necessary for Onboard Diagnostics Level II compliance. Therefore, it is recommended that an Experimental Permit be obtained from the California Air Resource Board to license and operate the vehicles for the durability of the demonstration in support of preparing a fully compliant and certifiable package that can be submitted.

  17. An In-situ materials analysis particle probe (MAPP) diagnostic to study particle density control and hydrogenic fuel retention in NSTX

    Energy Technology Data Exchange (ETDEWEB)

    Allain, Jean-Paul [Purdue Univ., West Lafayette, IN (United States)

    2014-09-05

    A new materials analysis particle probe (MAPP) was designed, constructed and tested to develop understanding of particle control and hydrogenic fuel retention in lithium-based plasma-facing surfaces in NSTX. The novel feature of MAPP is an in-situ tool to probe the divertor NSTX floor during LLD and lithium-coating shots with subsequent transport to a post-exposure in-vacuo surface analysis chamber to measure D retention. In addition, the implications of a lithiated graphite-dominated plasma-surface environment in NSTX on LLD performance, operation and ultimately hydrogenic pumping and particle control capability are investigated in this proposal. MAPP will be an invaluable tool for erosion/redeposition simulation code validation.

  18. Rise and subsequent decline of community-associated methicillin resistant Staphylococcus aureus ST30-IVc in Copenhagen, Denmark through an effective search and destroy policy

    DEFF Research Database (Denmark)

    Bartels, M D; Kristoffersen, K; Boye, K

    2010-01-01

    was insufficient and at least one person in each household was treated with systemic antibiotics. All families were MRSA negative at 1-year follow-up. The CA-MRSA clone ST30-IVc has been imported to Copenhagen, Denmark, primarily from the Philippines, and has spread through close contacts and in kindergartens...... to the Philippines. Household members were screened for MRSA and all members of families with MRSA carriers were offered treatment of the carrier state and were followed for 1 year. MRSA carriers were found in seven of 16 households and transmission occurred among close contacts and in kindergartens. Five days of ET....... Treatment of MRSA carriers was difficult and required many resources, but the clone was eventually successfully eliminated. The import of ST30-IVc to Denmark will continue, but the spread of the clone in Denmark can be kept to a minimum by direct intervention in the affected families....

  19. Role of IVC Filters in Endovenous Therapy for Deep Venous Thrombosis: The FILTER-PEVI (Filter Implantation to Lower Thromboembolic Risk in Percutaneous Endovenous Intervention) Trial

    International Nuclear Information System (INIS)

    Sharifi, Mohsen; Bay, Curt; Skrocki, Laura; Lawson, David; Mazdeh, Shahnaz

    2012-01-01

    Objectives: The purpose of this study was to evaluate the necessity of and recommend indications for inferior vena cava (IVC) filter implantation during percutaneous endovenous intervention (PEVI) for deep venous thrombosis (DVT).BackgroundPEVI has emerged as a powerful tool in the management of acute proximal DVT. Instrumentation of extensive fresh thrombus is potentially associated with iatrogenic pulmonary embolism (PE). The true frequency of this complication has not been studied in a randomized fashion. We evaluated IVC filter implantation during PEVI for DVT. Methods: A total of 141 patients with symptomatic proximal DVT undergoing PEVI for symptomatic DVT were randomized to receive an IVC filter (70 patients) or no filter (71 patients; control group). The anticoagulation and PEVI regimen were similar between the two groups. Patients with development of symptoms suggestive of PE underwent objective testing for PE. Results: PE developed in 1 of the 14 symptomatic patients in the filter group and 8 of the 22 patients in the control group (P = 0.048). There was no mortality in any group. Three patients (4.2%) in the control group had transient hemodynamic instability necessitating resuscitory efforts. Predictors of iatrogenic PE were found to be PE at admission; involvement of two or more adjacent venous segments with acute thrombus; inflammatory form of DVT (severe erythema, edema, pain, and induration); and vein diameter of ≥7 mm with preserved architecture. Conclusions: IVC filter implantation during PEVI reduces the risk of iatrogenic PE by eightfold without a mortality benefit. A selective approach may be exercised in filter implantation during PEVI.

  20. Role of IVC Filters in Endovenous Therapy for Deep Venous Thrombosis: The FILTER-PEVI (Filter Implantation to Lower Thromboembolic Risk in Percutaneous Endovenous Intervention) Trial

    Energy Technology Data Exchange (ETDEWEB)

    Sharifi, Mohsen, E-mail: seyedmohsensharifi@yahoo.com [Arizona Cardiovascular Consultants (United States); Bay, Curt [A.T. Still University, Arizona School of Health Sciences (United States); Skrocki, Laura; Lawson, David; Mazdeh, Shahnaz [Arizona Cardiovascular Consultants (United States)

    2012-12-15

    Objectives: The purpose of this study was to evaluate the necessity of and recommend indications for inferior vena cava (IVC) filter implantation during percutaneous endovenous intervention (PEVI) for deep venous thrombosis (DVT).BackgroundPEVI has emerged as a powerful tool in the management of acute proximal DVT. Instrumentation of extensive fresh thrombus is potentially associated with iatrogenic pulmonary embolism (PE). The true frequency of this complication has not been studied in a randomized fashion. We evaluated IVC filter implantation during PEVI for DVT. Methods: A total of 141 patients with symptomatic proximal DVT undergoing PEVI for symptomatic DVT were randomized to receive an IVC filter (70 patients) or no filter (71 patients; control group). The anticoagulation and PEVI regimen were similar between the two groups. Patients with development of symptoms suggestive of PE underwent objective testing for PE. Results: PE developed in 1 of the 14 symptomatic patients in the filter group and 8 of the 22 patients in the control group (P = 0.048). There was no mortality in any group. Three patients (4.2%) in the control group had transient hemodynamic instability necessitating resuscitory efforts. Predictors of iatrogenic PE were found to be PE at admission; involvement of two or more adjacent venous segments with acute thrombus; inflammatory form of DVT (severe erythema, edema, pain, and induration); and vein diameter of {>=}7 mm with preserved architecture. Conclusions: IVC filter implantation during PEVI reduces the risk of iatrogenic PE by eightfold without a mortality benefit. A selective approach may be exercised in filter implantation during PEVI.

  1. An insight on hydrogen fuel injection techniques with SCR system for NO{sub X} reduction in a hydrogen-diesel dual fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Saravanan, N. [ERC Engines, Hall 11A, Tata Motors, Pimpri, Pune 411019, Maharashtra (India); Nagarajan, G. [Department of Mechanical Engineering, ICE Division, College of Engineering, Guindy, Anna University-Chennai, Chennai 600 025 (India)

    2009-11-15

    Internal combustion engines continue to dominate in many fields like transportation, agriculture and power generation. Among the various alternative fuels, hydrogen is a long-term renewable and less polluting fuel (Produced from renewable energy sources). In the present experimental investigation, the performance and emission characteristics were studied on a direct injection diesel engine in dual fuel mode with hydrogen inducted along with air adopting carburetion, timed port and manifold injection techniques. Results showed that in timed port injection, the specific energy consumption reduces by 15% and smoke level by 18%. The brake thermal efficiency and NO{sub X} increases by 17% and 34% respectively compared to baseline diesel. The variation in performance between port and manifold injection is not significant. The unburnt hydrocarbons and carbon monoxide emissions are lesser in port injection. The oxides of nitrogen are higher in hydrogen operation (both port and manifold injection) compared to diesel engine. In order to reduce the NO{sub X} emissions, a selective catalytic converter was used in hydrogen port fuel injection. The NO{sub X} emission reduced upto a maximum of 74% for ANR (ratio of flow rate of ammonia to the flow rate of NO) of 1.1 with a marginal reduction in efficiency. Selective catalytic reduction technique has been found to be effective in reducing the NO{sub X} emission from hydrogen fueled diesel engines. (author)

  2. Photocatalytic degradation of H2S aqueous media using sulfide nanostructured solid-solution solar-energy-materials to produce hydrogen fuel.

    Science.gov (United States)

    Lashgari, Mohsen; Ghanimati, Majid

    2018-03-05

    H 2 S is a corrosive, flammable and noxious gas, which can be neutralized by dissolving in alkaline media and employed as H 2 -source by utilizing inside semiconductor-assisted/photochemical reactors. Herein, through a facile hydrothermal route, a ternary nanostructured solid-solution of iron, zinc and sulfur was synthesized in the absence and presence of Ag-dopant, and applied as efficient photocatalyst of hydrogen fuel production from H 2 S media. The effect of pH on the photocatalyst performance was scrutinized and the maximum activity was attained at pH=11, where HS - concentration is high. BET, diffuse reflectance and photoluminescence studies indicated that the ternary solid-solution photocatalyst, in comparison to its solid-solvent (ZnS), has a greater surface area, stronger photon absorption and less charge recombination, which justify its superiority. Moreover, the effect of silver-dopant on the photocatalyst performance was examined. The investigations revealed that although silver could boost the absorption of photons and increase the surface area, it could not appreciably enhance the photocatalyst performance due to its weak influence on retarding the charge-recombination process. Finally, the phenomenon was discussed in detail from mechanistic viewpoint. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. An Analysis of Environmental Dimensions Affected in Adoption of Hydrogen Fuel Cell Vehicles: A Study in Shah ALAM Industrial AREA, Selangor

    Directory of Open Access Journals (Sweden)

    Siron Rusinah

    2016-01-01

    Full Text Available The aim of the study is to identify the perceptions of respondents on environmental dimensions hat affected in adoption of hydrogen fuel cell vehicles. The study was conducted at Shah Alam industrial areas of Selangor, Malaysia, with the number of respondents are 120 respondents with various job positions that related with engineering and automobiles industry. The findings of the research shows that the dimensions of HFCV Internal Environmental total score of the items statement is 3.40 with the percentage of agreement in implementation is 3.72 percent, HFCV Environmental Information Systems shows that the total score of the items statement is 3.63 with the percentage of agreement on use to great extend is 42.5 percent, HFCV Cooperation with Customers shows that the total score of the items statement is 3.81 with the percentage of agreement on implementation is 44.2 percent. The findings on HFCV Eco Design shows that the total score of items statement is 4.02 with the percentage of agreement on implementation is 42.3 percent, HFCV Environmental Organizational Culture shows that the total score of the items statement is 3.37 with the percentage of agreement is 34.2 percent, HFCV Environmental Leadership shows that the total score of the items statement is 3.34 with the percentage of agreement is 48.2 percent. HFCV Proactive Green Innovation shows that the total score of items statement is 4.10 ahead of automobile got the highest mean score of 4.32 with the percentage of agreement is 41 percent. HFCV Environmental performance shows that the total score of the items statement is 3.87 with the percentage of agreement is 39 percent and the last environmental dimensions was HFCV Environmental Risks shows that the total score of the item statement is 4.00 with the percentage of agreement is 40 percent

  4. Switching to a U.S. hydrogen fuel cell vehicle fleet: The resultant change in emissions, energy use, and greenhouse gases

    Science.gov (United States)

    Colella, W. G.; Jacobson, M. Z.; Golden, D. M.

    This study examines the potential change in primary emissions and energy use from replacing the current U.S. fleet of fossil-fuel on-road vehicles (FFOV) with hybrid electric fossil fuel vehicles or hydrogen fuel cell vehicles (HFCV). Emissions and energy usage are analyzed for three different HFCV scenarios, with hydrogen produced from: (1) steam reforming of natural gas, (2) electrolysis powered by wind energy, and (3) coal gasification. With the U.S. EPA's National Emission Inventory as the baseline, other emission inventories are created using a life cycle assessment (LCA) of alternative fuel supply chains. For a range of reasonable HFCV efficiencies and methods of producing hydrogen, we find that the replacement of FFOV with HFCV significantly reduces emission associated with air pollution, compared even with a switch to hybrids. All HFCV scenarios decrease net air pollution emission, including nitrogen oxides, volatile organic compounds, particulate matter, ammonia, and carbon monoxide. These reductions are achieved with hydrogen production from either a fossil fuel source such as natural gas or a renewable source such as wind. Furthermore, replacing FFOV with hybrids or HFCV with hydrogen derived from natural gas, wind or coal may reduce the global warming impact of greenhouse gases and particles (measured in carbon dioxide equivalent emission) by 6, 14, 23, and 1%, respectively. Finally, even if HFCV are fueled by a fossil fuel such as natural gas, if no carbon is sequestered during hydrogen production, and 1% of methane in the feedstock gas is leaked to the environment, natural gas HFCV still may achieve a significant reduction in greenhouse gas and air pollution emission over FFOV.

  5. KILT (Kidney and IVC Abnormalities with Leg Thrombosis) Syndrome in a 41-Years-Old Man with Loin Pain and Fever.

    Science.gov (United States)

    Fung, James Kiujing; Yeung, Victor Hip Wo; Chu, Sau Kwan; Man, Chi Wan

    2017-05-01

    KILT syndrome is a rare condition composing the triad of kidney and inferior vena cava anomaly and extensive venous thrombosis. We present a case of newly diagnosed KILT syndrome in a 41-years-old gentleman presenting with loin pain and fever. Reviewing previous case reports, KILT syndrome is usually an incidental finding on imaging studies and there is a wide scope of initial clinical presentations. However, recent evidence suggests IVC anomaly may have caused subsequent renal hypoplasia. Identification of the underlying etiology may be helpful in planning early vascular intervention to treat the condition.

  6. Community-acquired necrotizing pneumonia caused by methicillin-resistant Staphylococcus aureus ST30-SCCmecIVc-spat019-PVL positive in San Antonio de Areco, Argentina

    Directory of Open Access Journals (Sweden)

    Silvina Fernández

    2015-03-01

    Full Text Available Community-acquired methicillin-resistant Staphylococcus aureus is the first cause of skin and soft tissue infections, but can also produce severe diseases such as bacteremia, osteomyelitis and necrotizing pneumonia. Some S. aureus lineages have been described in cases of necrotizing pneumonia worldwide, usually in young, previously healthy patients. In this work, we describe a fatal case of necrotizing pneumonia due to community-acquired methicillin-resistant S. aureus clone ST30-SCCmecIVc-spat019-PVL positive in an immunocompetent adult patient.

  7. Community-acquired necrotizing pneumonia caused by methicillin-resistant Staphylococcus aureus ST30-SCCmecIVc-spat019-PVL positive in San Antonio de Areco, Argentina.

    Science.gov (United States)

    Fernandez, Silvina; Murzicato, Sofía; Sandoval, Orlando; Fernández-Canigia, Liliana; Mollerach, Marta

    2015-01-01

    Community-acquired methicillin-resistant Staphylococcus aureus is the first cause of skin and soft tissue infections, but can also produce severe diseases such as bacteremia, osteomyelitis and necrotizing pneumonia. Some S. aureus lineages have been described in cases of necrotizing pneumonia worldwide, usually in young, previously healthy patients. In this work, we describe a fatal case of necrotizing pneumonia due to community-acquired methicillin-resistant S. aureus clone ST30-SCCmecIVc-spat019-PVL positive in an immunocompetent adult patient. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  8. Experiment on Synchronous Timing Signal Detection from ISDB-T Terrestrial Digital TV Signal with Application to Autonomous Distributed ITS-IVC Network

    Science.gov (United States)

    Karasawa, Yoshio; Kumagai, Taichi; Takemoto, Atsushi; Fujii, Takeo; Ito, Kenji; Suzuki, Noriyoshi

    A novel timing synchronizing scheme is proposed for use in inter-vehicle communication (IVC) with an autonomous distributed intelligent transport system (ITS). The scheme determines the timing of packet signal transmission in the IVC network and employs the guard interval (GI) timing in the orthogonal frequency divisional multiplexing (OFDM) signal currently used for terrestrial broadcasts in the Japanese digital television system (ISDB-T). This signal is used because it is expected that the automotive market will demand the capability for cars to receive terrestrial digital TV broadcasts in the near future. The use of broadcasts by automobiles presupposes that the on-board receivers are capable of accurately detecting the GI timing data in an extremely low carrier-to-noise ratio (CNR) condition regardless of a severe multipath environment which will introduce broad scatter in signal arrival times. Therefore, we analyzed actual broadcast signals received in a moving vehicle in a field experiment and showed that the GI timing signal is detected with the desired accuracy even in the case of extremely low-CNR environments. Some considerations were also given about how to use these findings.

  9. Type-IVC Secretion System: A Novel Subclass of Type IV Secretion System (T4SS) Common Existing in Gram-Positive Genus Streptococcus

    Science.gov (United States)

    Chen, Chen; Gao, George F.

    2012-01-01

    A growing number of pathogens are being found to possess specialized secretion systems which they use in various ways to subvert host defenses. Type IV secretion system (T4SS) is one of versatile secretion systems essential for the virulence and even survival of some bacteria species, and they enable the secretion of protein and DNA substrates across the cell envelope. T4SS was once believed to be present only in Gram-negative bacteria. In this study, we present evidence of a new subclass of T4SS, Type-IVC secretion system and indicate its common existence in the Gram-positive bacterial genus Streptococcus. We further identified that VirB1, VirB4, VirB6 and VirD4 are the minimal key components of this system. Using genome comparisons and evolutionary relationship analysis, we proposed that Type-IVC secretion system is movable via transposon factors and mediates the conjugative transfer of DNA, enhances bacterial pathogenicity, and could cause large-scale outbreaks of infections in humans. PMID:23056296

  10. DOE Hydrogen & Fuel Cell Overview

    Science.gov (United States)

    2011-01-13

    AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Department of Energy...Overview of Combined Heat+Power PowerElectricity Natural Gas Heat + Cooling Natural Gas or Biogas ...Fuel Cell Technologies Program eere.energy.gov Source: US DOE 10/2010 Biogas Benefits: Preliminary Analysis Stationary fuel

  11. WVU Hydrogen Fuel Dispensing Station

    Energy Technology Data Exchange (ETDEWEB)

    Davis, William [West Virginia University Research Corporation, Morgantown, WV (United States)

    2015-09-01

    The scope of this project was changed during the course of the project. Phase I of the project was to construct a site similar to the site at Central West Virginia Regional Airport in Charleston, WV to show that duplication of the site was a feasible method of conducting hydrogen stations. Phase II of the project was necessitated due to a lack of funding that was planned for the development of the station in Morgantown. The US Department of Energy determined that the station in Charleston would be dismantled and moved to Morgantown and reassembled at the Morgantown site. This necessitated storage of the components of the station for almost a year at the NAFTC Headquarters which caused a number of issues with the equipment that will be discussed in later portions of this report. This report will consist of PHASE I and PHASE II with discussions on each of the tasks scheduled for each phase of the project.

  12. Exploring Hydrogen Fuel Cell Technology

    Science.gov (United States)

    Brus, David; Hotek, Doug

    2010-01-01

    One of the most significant technological issues of the 21st Century is finding a way to fulfill the energy demands without destroying the environment through global warming and climate change. Worldwide human population is on the rise, and with it, the demand for more energy in pursuit of a higher quality of life. In the meantime, as people use…

  13. Multi-unit inertial fusion plants based on HYLIFE-II, with shared heavy-ion RIA driver and target factory, producing electricity and hydrogen fuel

    Energy Technology Data Exchange (ETDEWEB)

    Logan, G.; Moir, R. [Lawrence Livermore National Lab., CA (United States); Hoffman, M. [Univ. of California, Davis, CA (United States)

    1994-05-05

    Following is a modification of the IFEFUEL systems code, called IFEFUEL2, to treat specifically the HYLIFE-II target chamber concept. The same improved Recirculating Induction Accelerator (RIA) energy scaling model developed recently by Bieri is used in this survey of the economics of multi-unit IFE plants producing both electricity and hydrogen fuel. Reference cases will assume conventional HI-indirect target gains for a 2 mm spot, and improved HYLIFE-II BoP models as per Hoffman. Credits for improved plant availability and lower operating costs due to HYLIFE-II`s 30-yr target chamber lifetime are included, as well as unit cost reductions suggested by Delene to credit greater {open_quotes}learning curve{close_quotes} benefits for the duplicated portions of a multi-unit plant. To illustrate the potential impact of more advanced assumptions, additional {open_quotes}advanced{close_quotes} cases will consider the possible benefits of an MHD + Steam BoP, where direct MHD conversion of plasma from baseball-size LiH target blanket shells is assumed to be possible in a new (as yet undesigned) liquid Flibe-walled target chamber, together and separately, with advanced, higher-gain heavy-ion targets with Fast Ignitors. These runs may help decide the course of a possible future {open_quotes}HYLIFE-III{close_quotes} IFE study. Beam switchyard and final focusing system costs per target chamber are assumed to be consistent with single-sided illumination, for either {open_quotes}conventional{close_quotes} or {open_quotes}advanced{close_quotes} indirect target gain assumptions. Target costs are scaled according to the model by Woodworth. In all cases, the driver energy and rep rate for each chosen number of target chambers and total plant output will be optimized to minimize the cost of electricity (CoE) and the associated cost of hydrogen (CoH), using a relationship between CoE and CoH to be presented in the next section.

  14. Relationship between changes of blood HBV-DNA viral load and serum liver fibrosis markers (HA, LN, IV-C, PCIII) levels in patients with chronic hepatitis B

    International Nuclear Information System (INIS)

    Wang Yuanchi; Huang Jinwei

    2009-01-01

    Objective: To investigate the relationship between changes of blood HBV DNA viral load and serum liver fibrosis markers levels in patients with chronic hepatitis B. Methods: In 2002, 20 patients with hepatitis B were divided into two groups: Group A treated with antiviral ageat (n=10), Group B not treated.Five years later (2007) the blood viral load (with FQ-PCR) and serum levels of hepatic fibrosis markers (with RIA) were determined in these patients. Results: The average log viral load in serum in the tow groups were 3.56 ± 1.12 (treated group) and 7.76 ± 1.23 respectively with significant difference (P<0.05). In 2002, serum liver fibrosis markers (HA, LN, IV-C, PCIII) levels were about the same in the two groups were (82.72 ± 30.62μg/ml, 71.18 ± 26.71μg/ml, 93.77 ± 69.87μg/ml, 91.4 ± 18.64μg/ml and 79.32 ± 31.34μg/ml, 70.25 ± 28.23)μg/ml, 90.35 ± 67.81μg/ml, 85.77 ± 20.56μg/ml respectively). In 2007, in the treated patients, serum liver fibrosis markers HA, LN, IV-C, PCIII levels were 85.72 ± 29.52μg/ml, 70.18 ± 25.4μg/ml, 94.2 ± 70.92μg/ml, 93.4 ± 19.32μg/ml respectively However, in the non-treated groups, the serum HA, LN, IV-C, PCIII levels were105.67 ± 28.54μg/ml, 97.75 ± 26.25μg/ml, 132 ± 72.13μg/ml, 120.72 ± 19.87μg/ml, being significantly higher than those in the treated group (P<0.05). Conclusion: Effective decrease of the viral load might control the progress of hepatic fibrosis in patients with chronic hepatitis B. (authors)

  15. NEDO Forum 2001. Session on hydrogen/PEFC (Toward realization of hydrogen/fuel cell society); NEDO Forum 2001. Suiso PEFC session (suiso nenryo denchi shakai no jitsugen ni mukete)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-09-20

    The presentations made at the above-named session of the NEDO (New Energy and Industrial Technology Development Organization) forum held in Tokyo on September 20, 2001, are collected in this report. Introduced in a lecture entitled 'March toward hydrogen/fuel cell society' were NEDO's PEFC (polymer electrolyte fuel cell) related project of its hydrogen energy technology development office and the WE-NET (World Energy Network) hydrogen program. Reported in a lecture entitled 'Toward the practical application of PEFC' were Yamanashi University Clean Energy Center's achievements in the study of polymer electrolyte film, electrodes and separators for PEFC, removal of carbon monoxide by selective oxidation, and so forth. Discussed in a lecture entitled 'Development of high efficiency energy system technologies for transportation and residential/commercial sectors' were the development of a hydrogen-fueled 1kW stack and the result of efforts to develop element technologies for power generation systems fueled by natural gas, methanol, etc. Explained also were the outline and the progress of the project in relation with the fuel cell popularization infrastructure construction project and the fiscal 2001 research and development and the future outlook in relation with the 2nd-phase technology development for WE-NET. (NEDO)

  16. Achievement report on research and development in the Sunshine Project in fiscal 1978. Research on hydrogen energy subsystems (research on hydrogen fueled automobile systems); 1978 nendo suiso energy subsystem no kenkyu seika hokokusho. Suiso jidosha system no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1979-03-01

    This paper describes the result of discussions on hydrogen fueled automobiles in fiscal 1978. Hydrogen fueled automobiles have a difficulty in developing methods for transporting hydrogen, whereas the liquefied hydrogen method and the metal hydride method are being studied in parallel at the present. It is also necessary to solve such basic problems as the method for supplying hydrogen to engines, the injection method, and countermeasures for abnormal combustion. Safety assurance is also important. Very little information is available presently on methods for storing hydrogen inside a car and supplying thereof, which are required for evaluating utilization of liquefied hydrogen to automobiles. Demonstrative surveys and researches are required to acquire basic materials for hydrogen feeding methods in broader meaning including storage and control. Therefore, fiscal 1977 has begun trial fabrication of experimental liquefied hydrogen tanks, and preliminary and experimental researches on types and materials for feed pumps. Fiscal 1978 has moved forward improvements in prototype tank performance (heat insulation method to reduce evaporation loss), trial fabrication of liquid level meters, trial fabrication of feed pumps (especially selection of materials for the sliding parts), and researches on flow rate control methods. Drawings for modification and experiment of the liquefied hydrogen tanks were prepared, and the promising candidates were selected for material combination in pump sliding parts. Durability tests are continuing thereon. Flow rate control was also discussed. (NEDO)

  17. Achievement report on research and development in the Sunshine Project in fiscal 1979. Research hydrogen energy subsystems (Research on hydrogen fueled automobiles); 1979 nendo suiso energy subsystem no kenkyu seika hokokusho. Suiso jidosha system no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-03-01

    This paper describes research achievements in fiscal 1979 in research on hydrogen fueled automobiles as a research on hydrogen energy subsystems. The previous fiscal year has researched heat insulation methods to reduce evaporation loss from a hydrogen tank, prototype liquid level meters, prototype feed pumps (especially material selection for sliding parts) and a flow rate control method. Fiscal 1979 performed measurements of temperatures in different parts in the tank to elucidate how the heat makes invasion. Measurements were performed for the pump on suction valve behavior, internal pump compression force, liner temperatures, and leakage amount. The status of operation was identified and a high performance pump for use in very low temperatures was developed successfully. The pump has high delivery pressure, good durability, and capability of fine adjustment in the delivery quantity. This made the direct injection system for hydrogen fuel possible. Injection of hydrogen into an engine was possible by vaporizing liquefied hydrogen and supplying it as a low temperature gas used at 0 to -40 degrees C. The system has high efficiency. Fuel feed control was possible at the same level as in the existing automobiles. The prototype direct injection system can handle stably the load in actual cars. Material for the fuel tank is an important problem in terms of weight, whose solution is urged. (NEDO)

  18. Opportunities and Difficulties in the Implementation of Projects Financed Through the Interreg IVC Program in Romania. Case Study: The Project "Public Policies and Social Enterprises"

    Directory of Open Access Journals (Sweden)

    Daniela PÎRVU

    2011-02-01

    Full Text Available In Europe today, economic success is often dependent on a region’s capacity to develop networks with other regions. Cooperation and experience sharing between regions can be a key trigger in stimulating a dynamic, forwardlooking regional development process. The EU has an important role to play in brokering and supporting partnerships between regions within the Union. Thousands of projects developed over many years under the INTERREG initiative have demonstrated the benefits for regions of working in partnership, sharing ideas and charting new and innovative ways of harnessing European investment. The analysis of the implementation of the projects financed through the INTERREG IVC Program proves that the development of the interregional European cooperation is constrained by the practical difficulties generated by various administrative systems and by the differences among competences on the levels of the public administration of the European Union member states.

  19. Effect of B-mercaptoethanol on the viability of IVM/IVF/IVC bovine embryos during long-distance transportation in plastic straws.

    Science.gov (United States)

    Takahashi, H; Kuwayama, M; Hamano, S; Takahashi, M; Okano, A; Kadokawa, H; Kariya, T; Nagai, T

    1996-10-15

    Experiments were conducted to assess the effect of beta-mercaptoethanol (beta-ME) on the quality and viability of bovine blastocysts derived from in-vitro culture (IVC) of in-vitro matured and fertilized (TVM-IVF) oocytes during their transport between 2 distant places. Follicular oocytes were collected from ovaries obtained at a slaughterhouse and were cultured for 20 to 21 h in modified TCM-199. The IVM oocytes were fertilized in vitro with frozen-thawed spermatozoa. Fertilized oocytes were cultured for 7 d, and embryos that developed to the blastocyst stage were used for the experiments. The blastocysts, packed in straws with transportation medium that consisted of modified TCM-199 with HEPES equilibrated in air and supplemented with 20 % calf serum and 0, 10, 50, 100 or 150 microM beta-ME, were transported at 37 degrees C from Tokyo to Sapporo by air (18.3 h). The quality of blastocysts was assessed and ranked as excellent (A), good (B), fair (C) or poor (D) after transportation. The percentages of blastocysts ranked as A or B were significantly higher (P plastic straws for several hours without control of CO2 and that the concentration of beta-ME used in this experiment is not detrimental to the blastocysts.

  20. Achievement report for 1st phase (fiscal 1974-80) Sunshine Program research and development - Hydrogen energy. Research on hydrogen-fueled engine; 1974-1980 nendo suiso energy seika hokokusho. Suiso nenryo gendoki no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-03-01

    The research aims to acquire data necessary for designing an engine, which is fueled by hydrogen stored in metal hydrides, for an automobile power plant. It covers the characteristics of hydrogen and their theoretical examination, basic studies on the turbulent mixing and combustion of hydrogen, research using a single-cylinder engine, changes brought into engine performance upon addition of hydrogen, etc. When hydrogen is burned in a spark ignition engine, flashback to the induction system is prone to occur. But this is prevented by directly injecting nothing but hydrogen into the cylinder. In the case of hydrogen fuel, there is the problem of thermal NO generation. Since a hydrogen/air flame is higher in temperature than flames in the case of other fuels, it generates more NO. As techniques for lowering the flame temperature, there are lean fuel combustion, water vapor injection, delayed ignition timing, etc. For the improvement of power and performance, increasing the engine revolution and pressurizing the inlet air are the methods, but both have their own shortcomings. An engine equipped with a third valve is experimentally constructed in this research, which is theoretically free of flashback, suppresses a reduction in the inlet air volume, and necessitates no high-pressure injection system. (NEDO)

  1. Hydrogen engine performance analysis project. Second annual report

    Energy Technology Data Exchange (ETDEWEB)

    Adt, Jr., R. R.; Swain, M. R.; Pappas, J. M.

    1980-01-01

    Progress in a 3 year research program to evaluate the performance and emission characteristics of hydrogen-fueled internal combustion engines is reported. Fifteen hydrogen engine configurations will be subjected to performance and emissions characterization tests. During the first two years, baseline data for throttled and unthrottled, carburetted and timed hydrogen induction, Pre IVC hydrogen-fueled engine configurations, with and without exhaust gas recirculation (EGR) and water injection, were obtained. These data, along with descriptions of the test engine and its components, the test apparatus, experimental techniques, experiments performed and the results obtained, are given. Analyses of other hydrogen-engine project data are also presented and compared with the results of the present effort. The unthrottled engine vis-a-vis the throttled engine is found, in general, to exhibit higher brake thermal efficiency. The unthrottled engine also yields lower NO/sub x/ emissions, which were found to be a strong function of fuel-air equivalence ratio. (LCL)

  2. Study on the diagnostic value of determination of serum IV-C, PC III, HA, LN and PLD concentrations for hepatic fibrosis in patients with B hepatitis of various types

    International Nuclear Information System (INIS)

    Li Zhuocheng; Chen Jianxiong; Xiong Ying

    2004-01-01

    Objective: To investigate the changes of serum levels of collagen type IV(IV-C), procollagen type III (PC III), hyaluronic acid (HA), laminin (LN) and prolidase (PLD) and their relationship with hepatic fibrosis in patients with B hepatitis of different types. Methods: Serum levels of IV-C, PC III, HA, LN and PLD were measured with RIA in 39 controls and 103 patients with HBV infection of various types (including acute hepatitis AH n=19, chronic persistent hepatitis CPH n=29, Chronic active hepatitis CAH n=25 and liver cirrhosis LH n=30. Degree of hepatic fibrosis (Grade 0-4) was ascertained with liver biopsy in 35 patients (CAH16, LC19) and correlationship with the corresponding levels of these 5 serum markers was steadied. Results: 1) Serum levels of IV-C, PC III, HA, LN and PLD were significantly higher in patients with CAH and LC than those in other patients and controls (P 0.05). 3) Serum levels of these markers were all positively correlated with the degree of hepatic fibrosis noted in the biopsy specimens obtained from patients with CAH (n=16) and LC (n=19) (r=+0.64 - + 0.89, P<0.01). Conclusion: Serum levels of these markers could reflect the degree of hepatic fibrosis and severity of liver damage; determination of which was of diagnostic and even prognostic value. HA and LN appeared to be better correlated with degree of hepatic fibrosis than the remaining three markers did. (authors)

  3. Advanced compressed hydrogen fuel storage systems

    International Nuclear Information System (INIS)

    Jeary, B.

    2000-01-01

    Dynetek was established in 1991 by a group of private investors, and since that time efforts have been focused on designing, improving, manufacturing and marketing advanced compressed fuel storage systems. The primary market for Dynetek fuel systems has been Natural Gas, however as the automotive industry investigates the possibility of using hydrogen as the fuel source solution in Alternative Energy Vehicles, there is a growing demand for hydrogen storage on -board. Dynetek is striving to meet the needs of the industry, by working towards developing a fuel storage system that will be efficient, economical, lightweight and eventually capable of storing enough hydrogen to match the driving range of the current gasoline fueled vehicles

  4. Biorefinery and Hydrogen Fuel Cell Research

    Energy Technology Data Exchange (ETDEWEB)

    K.C. Das; Thomas T. Adams; Mark A. Eiteman; John Stickney; Joy Doran Peterson; James R. Kastner; Sudhagar Mani; Ryan Adolphson

    2012-06-12

    In this project we focused on several aspects of technology development that advances the formation of an integrated biorefinery. These focus areas include: [1] establishment of pyrolysis processing systems and characterization of the product oils for fuel applications, including engine testing of a preferred product and its pro forma economic analysis; [2] extraction of sugars through a novel hotwater extaction process, and the development of levoglucosan (a pyrolysis BioOil intermediate); [3] identification and testing of the use of biochar, the coproduct from pyrolysis, for soil applications; [4] developments in methods of atomic layer epitaxy (for efficient development of coatings as in fuel cells); [5] advancement in fermentation of lignocellulosics, [6] development of algal biomass as a potential substrate for the biorefinery, and [7] development of catalysts from coproducts. These advancements are intended to provide a diverse set of product choices within the biorefinery, thus improving the cost effectiveness of the system. Technical effectiveness was demonstrated in the pyrolysis biooil based diesel fuel supplement, sugar extraction from lignocelluose, use of biochar, production of algal biomass in wastewaters, and the development of catalysts. Economic feasibility of algal biomass production systems seems attractive, relative to the other options. However, further optimization in all paths, and testing/demonstration at larger scales are required to fully understand the economic viabilities. The various coproducts provide a clear picture that multiple streams of value can be generated within an integrated biorefinery, and these include fuels and products.

  5. Issues affecting the acceptance of hydrogen fuel

    International Nuclear Information System (INIS)

    Schulte, I.; Hart, D.; Vorst, R. van der

    2004-01-01

    While the topic of hydrogen as an alternative vehicle fuel is gaining increasing attention internationally, one significant aspect of its introduction has been given less attention than others: the public acceptance of such a new technology and fuel. After reviewing the existing literature on acceptance, risk perception and customer satisfaction, this paper describes the development of a model that illustrates important aspects in influencing a person's attitude towards a new product. 'Values', 'wants' and 'perception' are the three components found to influence acceptance, they themselves are affected by 'social background' and 'experience'. Suggestions are then given on how to use marketing methods, education projects and product exposure in order to maximise the likelihood of a successful introduction of hydrogen as an alternative fuel. (author)

  6. Hydrogen, Fuel Cells & Infrastructure Technologies Program

    Energy Technology Data Exchange (ETDEWEB)

    2005-03-01

    This plan details the goals, objectives, technical targets, tasks and schedule for EERE's contribution to the DOE Hydrogen Program. Similar detailed plans exist for the other DOE offices that make up the Hydrogen Program.

  7. Achievement report for fiscal 2000. Phase II research and development task-5 for hydrogen utilizing international clean energy system technology (WE-NET) (Development of hydrogen fueled automobile system); 2000 nendo suiso riyo kokusai clean energy system gijutsu (WE-NET) dai 2 ki kenkyu kaihatsu. Task 5. Suiso jidosha system no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    This paper describes the achievements in fiscal 2000 from the WE-NET Phase II for Task-5, the development of a hydrogen fueled automobile system. For a fast filling method using a hydrogen absorbing alloy as the fuel tank, a rare earth system, the Laves system, and a body-centered cubic system were selected to discuss filling time when the plate-fin system tank and the divided system tank are used. Either system was found capable of filling 80% of the effective hydrogen absorbing amount within 10 minutes, having achieved the target. Guidelines were obtained for the design aiding method by using the cooling water flow rates, temperatures, and simulations. In the safety assessment, even the spontaneously combusting alloy of Category 1 in the Fire Fighting Law did not cause ignition even if the tank was damaged and the alloy was discharged in the dropping/falling weight tests. It was inferred that the ignition temperature is not reached because of the self-cooling made when hydrogen is discharged from the alloy. In the fire resistance test, the tank temperature was found not to rise as long as hydrogen is discharged from the alloy. Since the temperature rise and damage could occur if the discharge has been finished completely, discussions are required on materials and the soluble plug. Deformation may occur in the initial stage of the hydrogen absorbing and discharging cycles, but it would not occur after 5,000 cycles. (NEDO)

  8. Achievement report for fiscal 2000 on the phase II research and development for hydrogen utilizing international clean energy system technology (WE-NET). Task 6. Development of fuel cell of pure hydrogen fueled solid polymer type; 2000 nendo suiso riyo kokusai clean energy system gijutsu (WE-NET) dai 2 ki kenkyu kaihatsu. Task 6. Junsuiso kyokyu kotai kobunshigata nenryo denchi no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    This paper describes the achievements in fiscal 2000 from the WE-NET Phase II for research and development Task-6. The objective is to verify performance and reliability, by means of field tests, of a power generation plant using fuel cells of pure hydrogen fueled solid polymer type with power transmission terminal efficiency of 45% and output of 30 kW. The fuel cells were developed by using the cathode humidification process as a humidification method suitable for operation at high utilization rates. With a three-cell stack made by using this humidification process (having an effective area of 289 cm{sup 2}), verification was made on the current density of 0.2A/cm{sup 2}, the characteristics of 0.75V or higher, and the uniform voltage distribution performance being the immediate targets. In order to mitigate the hydrogen utilization in the fuel cells, discussions were given on the serial flow system that divides the laminated cells into two blocks. Thus, operation was found possible with the utilization rate in each block reduced to about 80% by selecting an adequate division rate even if the hydrogen utilization rate is 96% in the entire stack. Stable operation has been performed in the 5-kW class power generation test using the cathode interior humidifying system. Specifications for 30-kW class power plant, system configuration, safety, and material balance were discussed. The basic design was made on the hydrogen gas humidity adjusting system. (NEDO)

  9. Three dimensional culture of fresh and vitrified mouse pre-antral follicles in a hyaluronan-based hydrogel: a preliminary investigation of a novel biomaterial for in vitro follicle maturation

    Directory of Open Access Journals (Sweden)

    Desai Nina

    2012-06-01

    Full Text Available Abstract Background Folliculogenesis within the ovary requires interaction between somatic cell components and the oocyte. Maintenance of 3-dimensional (3-D architecture and granulosa-oocyte interaction may be critical for successful in vitro maturation of follicles. Testing of novel biomaterials for the 3-D culture of follicles may ultimately lead to a culture model that can support the longer in vitro culture intervals needed for in vitro maturation of human oocytes from ovarian tissue biopsies. Methods A novel tyramine-based hyaluronan (HA hydrogel was tested for its biocompatibility with ovarian follicles. The HA was prepared at concentrations from 2 to 5 mg/ml. HA hydrogel was also formulated and tested with matrix proteins (ECM. Enzymatically isolated pre-antral follicles from the ovaries of 10–12 day SJL pups were divided amongst control (CT and HA treatments. The growth of both fresh and vitrified follicles was assessed after encapsulation in the hydrogel. The basal culture medium was MEM alpha supplemented with FSH, LH, ITS and 5% FBS. Maturation was triggered by addition of hCG and EGF after in vitro culture (IVC. Outcome parameters monitored were follicle morphology, survival after IVC, antrum formation, GVBD and MII formation. Differences between treatments were analyzed. Results HA and ECM-HA encapsulated follicles looked healthy and maintained their 3-D architecture during IVC. In control cultures, the follicles flattened and granulosa:oocyte connections appeared fragile. Estradiol secretion per follicle was significantly higher by Day 12 in ECM-HA compared to HA or CT (4119, 703 and 1080 pg/ml, respectively. HA and ECM-HA cultured follicles had similar survival rates (62% and 54%, respectively, percent GV breakdown (96–97%, MII formation (47–48% and oocyte diameters at the end of IVC. Control cultures differed significantly in percent GVBD (85% and MII formation (67% . Vitrified-warmed follicles encapsulated in HA had

  10. PRE-DIABETES

    OpenAIRE

    Akula Annapurna

    2013-01-01

    Pre-diabetes is a condition where the body's cells begin to show resistance to insulin. Glucose circulates in the blood instead of being used by the cells for energy. Blood sugar levels become elevated. Increased weight, unhealthy diet and a sedentary lifestyle can lead to pre-diabetes. WHAT IS PRE-DIABETES A diagnosis of pre-diabetes means that the cells in your body are becoming resistant to insulin and your blood glucose levels are higher than they should be. Since the levels aren't as hig...

  11. (AGA) Pre Term Babies

    African Journals Online (AJOL)

    Haematological Indices in Healthy Appropriate For-Gestational-Age (AGA) Pre Term Babies. ... International Journal of Medicine and Health Development. Journal Home ... Patient and Methods: All consecutive healthy pre-term new born babies delivered at UNTH and admitted into the hospital NBSCU were included.

  12. Pre-Algebra Lexicon.

    Science.gov (United States)

    Hayden, Dunstan; Cuevas, Gilberto

    The pre-algebra lexicon is a set of classroom exercises designed to teach the technical words and phrases of pre-algebra mathematics, and includes the terms most commonly found in related mathematics courses. The lexicon has three parts, each with its own introduction. The first introduces vocabulary items in three groups forming a learning…

  13. PreCam

    Energy Technology Data Exchange (ETDEWEB)

    Allam, Sahar S. [Fermilab; Tucker, Douglas L. [Fermilab

    2015-01-01

    The Dark Energy Survey (DES) will be taking the next step in probing the properties of Dark Energy and in understanding the physics of cosmic acceleration. A step towards the photometric calibration of DES is to have a quick, bright survey in the DES footprint (PreCam), using a pre-production set of the Dark Energy Camera (DECam) CCDs and a set of 100 mm×100 mm DES filters. The objective of the PreCam Survey is to create a network of calibrated DES grizY standard stars that will be used for DES nightly calibrations and to improve the DES global relative calibrations. Here, we describe the first year of PreCam observation, results, and photometric calibrations.

  14. Pre-Clinical Model to Study Recurrent Venous Thrombosis in the Inferior Vena Cava.

    Science.gov (United States)

    Andraska, Elizabeth A; Luke, Catherine E; Elfline, Megan A; Henke, Samuel P; Madapoosi, Siddharth S; Metz, Allan K; Hoinville, Megan E; Wakefield, Thomas W; Henke, Peter K; Diaz, Jose A

    2018-06-01

     Patients undergoing deep vein thrombosis (VT) have over 30% recurrence, directly increasing their risk of post-thrombotic syndrome. Current murine models of inferior vena cava (IVC) VT model host one thrombosis event.  We aimed to develop a murine model to study IVC recurrent VT in mice.  An initial VT was induced using the electrolytic IVC model (EIM) with constant blood flow. This approach takes advantage of the restored vein lumen 21 days after a single VT event in the EIM demonstrated by ultrasound. We then induced a second VT 21 days later, using either EIM or an IVC ligation model for comparison. The control groups were a sham surgery and, 21 days later, either EIM or IVC ligation. IVC wall and thrombus were harvested 2 days after the second insult and analysed for IVC and thrombus size, gene expression of fibrotic markers, histology for collagen and Western blot for citrullinated histone 3 (Cit-H3) and fibrin.  Ultrasound confirmed the first VT and its progressive resolution with an anatomical channel allowing room for the second thrombus by day 21. As compared with a primary VT, recurrent VT has heavier walls with significant up-regulation of transforming growth factor-β (TGF-β), elastin, interleukin (IL)-6, matrix metallopeptidase 9 (MMP9), MMP2 and a thrombus with high citrullinated histone-3 and fibrin content.  Experimental recurrent thrombi are structurally and compositionally different from the primary VT, with a greater pro-fibrotic remodelling vein wall profile. This work provides a VT recurrence IVC model that will help to improve the current understanding of the biological mechanisms and directed treatment of recurrent VT. Schattauer GmbH Stuttgart.

  15. Design of a photovoltaic-hydrogen-fuel cell energy system

    Energy Technology Data Exchange (ETDEWEB)

    Lehman, P A; Chamberlin, C E [Humboldt State Univ., Arcata, CA (US). Dept. of Environmental Resources Engineering

    1991-01-01

    The design of a stand-alone renewable energy system using hydrogen (H{sub 2}) as the energy storage medium and a fuel cell as the regeneration technology is reported. The system being installed at the Humboldt State University Telonicher Marine Laboratory consists of a 9.2 kW photovoltaic (PV) array coupled to a high pressure, bipolar alkaline electrolyser. The array powers the Laboratory's air compressor system whenever possible; excess power is shunted to the electrolyser for hydrogen and oxygen (O{sub 2}) production. When the array cannot provide sufficient power, stored hydrogen and oxygen are furnished to a proton exchange membrane fuel cell which, smoothly and without interruption, supplies the load. In reporting the design, details of component selection, sizing, and integration, control system logic and implementation, and safety considerations are discussed. Plans for a monitoring network to chronicle system performance are presented, questions that will be addressed through the monitoring program are included, and the present status of the project is reported. (Author).

  16. Hydrogen, fuel cells and renewable energy integration in islands

    International Nuclear Information System (INIS)

    Bauen, A.; Hart, D.; Foradini, F.; Hart, D.

    2002-01-01

    Remote areas such as islands rely on costly and highly polluting diesel and heavy fuel oil for their electricity supply. This paper explored the opportunities for exploiting economically and environmentally viable renewable energy sources, in particular hydrogen storage, on such islands. In particular, this study focused on addressing the challenge of matching energy supply with demand and with technical issues regarding weak grids that are hindered with high steady state voltage levels and voltage fluctuations. The main technical characteristics of integrated renewable energy and hydrogen systems were determined by modelling a case study for the island of El Hierro (Canary Islands). The paper referred to the challenges regarding the technical and economic viability of such systems and their contribution to the economic development of remote communities. It was noted that energy storage plays an important role in addressing supply and demand issues by offering a way to control voltage and using surplus electricity at times of low load. Electrical energy can be stored in the form of potential or chemical energy. New decentralized generation technologies have also played a role in improving the energy efficiency of renewable energy sources. The feasibility of using hydrogen for energy storage was examined with particular reference to fuel-cell based energy supply in isolated island communities. 4 refs., 5 figs

  17. Fabrication and characterisation of hydrogen fuel cell membrane electrode assemblies

    CSIR Research Space (South Africa)

    Mathe

    2006-09-01

    Full Text Available stream_source_info Mathe_2006.pdf.txt stream_content_type text/plain stream_size 1 Content-Encoding ISO-8859-1 stream_name Mathe_2006.pdf.txt Content-Type text/plain; charset=ISO-8859-1 ...

  18. Hydrogen fuel cell vehicles for the 3rd millenniums

    International Nuclear Information System (INIS)

    Fahmy, F.H.

    2006-01-01

    As the world population increases, so does the demand for transportation. Automobiles, being the most common means of transportation are on of the main sources pollution. Therefore, in order to meet the needs of society and to protect the environment, scientists began looking for a new solution to this problem. Before they suggested any answers, the scientists first looked at all aspects surrounding the issue. Fuel cell can be promoted energy diversity and a transition to renewable energy sources. This paper presents a new friendly environmental vehicles. The fuel of this vehicles is a renewable sources, solar radiation, PV arrays, electrolyzer, hydrogen and fuel cell. All the results show the capability of vehicle's design with all the details of each main component for several varieties of vehicles for transportation. This new idea realizes clean and healthy environment vehicles

  19. Hydrogen Fuel Cell: Research Progress and Near-Term Opportunities

    Science.gov (United States)

    2009-04-27

    effort brings together automobile and ener- gy companies , as well as their suppliers and other stakeholders, to evaluate light-duty fuel cell vehicles...emissions compared to conventional power technologies. Grocers, banks, tire and hardware companies , logistics providers, and others in the private sector...Term Direct Hydrogen Proton Exchange Membrane (PEM) Fuel Cell Markets, April 2007. 2. Assumptions: Operate 7 hours/shift, 3 shifts/day, 7 days/week

  20. Hydrogen-fuel-powered bell segments of biomimetic jellyfish

    International Nuclear Information System (INIS)

    Tadesse, Yonas; Villanueva, Alex; Priya, Shashank; Haines, Carter; Novitski, David; Baughman, Ray

    2012-01-01

    Artificial muscles powered by a renewable energy source are desired for joint articulation in bio-inspired autonomous systems. In this study, a robotic underwater vehicle, inspired by jellyfish, was designed to be actuated by a chemical fuel source. The fuel-powered muscles presented in this work comprise nano-platinum catalyst-coated multi-wall carbon nanotube (MWCNT) sheets, wrapped on the surface of nickel–titanium (NiTi) shape memory alloy (SMA). As a mixture of oxygen and hydrogen gases makes contact with the platinum, the resulting exothermic reaction activates the nickel–titanium (NiTi)-based SMA. The MWCNT sheets serve as a support for the platinum particles and enhance the heat transfer due to the high thermal conductivity between the composite and the SMA. A hydrogen and oxygen fuel source could potentially provide higher power density than electrical sources. Several vehicle designs were considered and a peripheral SMA configuration under the robotic bell was chosen as the best arrangement. Constitutive equations combined with thermodynamic modeling were developed to understand the influence of system parameters that affect the overall actuation behavior of the fuel-powered SMA. The model is based on the changes in entropy of the hydrogen and oxygen fuel on the composite actuator within a channel. The specific heat capacity is the dominant factor controlling the width of the strain for various pulse widths of fuel delivery. Both theoretical and experimental strains for different diameter (100 and 150 µm) SMA/MWCNT/Pt fuel-powered muscles with dead weight attached at the end exhibited the highest magnitude under 450 ms of fuel delivery within 1.6 mm diameter conduit size. Fuel-powered bell deformation of 13.5% was found to be comparable to that of electrically powered (29%) and natural jellyfish (42%). (paper)

  1. Conversion of carbohydrate into hydrogen fuel by a photocatalytic process

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, T; Sakata, T

    1980-01-01

    The conversion of carbohydrates into H by a photocatalytic process is described. Powders of RuO/sub 2/, TiO/sub 2/, and Pt (weight ratio 10:100:5) were dissolved in H/sub 2/O containing sugar, starch, or cellulose and irradiated with UV. The cellulose reaction was also performed in 6M NaOH. The RuO/sub 2/-TiO/sub 2/-Pt powder acts as an electrochemical microcell; light of energy larger than the band gap of TiO/sub 2/ produces electron-hole pairs which separate and produce redox reactions at the particle-solution interface. The gases evolved using H/sub 2/O were mainly H and CO/sub 2/. H and Na/sub 2/CO/sub 3/ or NaHCO/sub 3/ were produced on irradiation of the NaOH solution at increased rates with respect to reactions in water.

  2. Predicting the Liquid Lengths of Heavy Hydrogen Fuels

    National Research Council Canada - National Science Library

    Hoogterp, Laura L

    2003-01-01

    .... Using models formulated by previous researchers as well as the thermodynamic properties for three fuel surrogates the liquid length can be determined for diesel fuel, JP8 as well as provide a model...

  3. Direct hydrogen fuel cell systems for hybrid vehicles

    Science.gov (United States)

    Ahluwalia, Rajesh K.; Wang, X.

    Hybridizing a fuel cell system with an energy storage system offers an opportunity to improve the fuel economy of the vehicle through regenerative braking and possibly to increase the specific power and decrease the cost of the combined energy conversion and storage systems. Even in a hybrid configuration it is advantageous to operate the fuel cell system in a load-following mode and use the power from the energy storage system when the fuel cell alone cannot meet the power demand. This paper discusses an approach for designing load-following fuel cell systems for hybrid vehicles and illustrates it by applying it to pressurized, direct hydrogen, polymer-electrolyte fuel cell (PEFC) systems for a mid-size family sedan. The vehicle level requirements relative to traction power, response time, start-up time and energy conversion efficiency are used to select the important parameters for the PEFC stack, air management system, heat rejection system and the water management system.

  4. Energizing Engineering Students with Hydrogen Fuel Cell Project

    Science.gov (United States)

    Cannell, Nori; Zavaleta, Dan

    2010-01-01

    At Desert Vista High School, near Phoenix, Arizona, Perkins Innovation Grant funding is being used to fund a program that is helping to prepare students for careers in engineering by giving them hands-on experience in areas like hydrogen generation and fuel cell utilization. As one enters Dan Zavaleta's automotive and engineering classroom and lab…

  5. Building the hydrogen/fuel cell industry: an EDC perspective

    International Nuclear Information System (INIS)

    FitzGerald, A.

    2004-01-01

    'Full text:' Canada has world-leading expertise in a number of hydrogen and fuel cell research segments. However, there are no guarantees that a strong research position necessarily translates into a large industry sector. The challenge facing Canada is to remain a leader in the coming years and decades as this hub of research activity evolves into an actual business sector. Many other countries are actively investing in hydrogen and fuel cell research. If these countries and their national governments are more committed than Canada to this commercial pursuit, then we will be left behind. Mr. Stothart's presentation will highlight a number of observations and recommendations regarding what is needed to build a successful hydrogen and fuel cell sector in Canada. (author)

  6. Effect of ramp-cavity on hydrogen fueled scramjet combustor

    Directory of Open Access Journals (Sweden)

    J.V.S. Moorthy

    2014-03-01

    Full Text Available Sustained combustion and optimization of combustor are the two challenges being faced by combustion scientists working in the area of supersonic combustion. Thorough mixing, lower stagnation pressure losses, positive thrust and sustained combustion are the key issues in the field of supersonic combustion. Special fluid mechanism is required to achieve good mixing. To induce such mechanisms in supersonic inflows, the fuel injectors should be critically shaped incurring less flow losses. Present investigations are focused on the effect of fuel injection scheme on a model scramjet combustor performance. Ramps at supersonic flow generate axial vortices that help in macro-mixing of fuel with air. Interaction of shocks generated by ramps with the fuel stream generates boro-clinic torque at the air & liquid fuel interface, enhancing micro-mixing. Recirculation zones present in cavities increase the residence time of the combustible mixture. Making use of the advantageous features of both, a ramp-cavity combustor is designed. The combustor has two sections. First, constant height section consists of a backward facing step followed by ramps and cavities on both the top and bottom walls. The ramps are located alternately on top and bottom walls. The complete combustor width is utilized for the cavities. The second section of the combustor is diverging area section. This is provided to avoid thermal choking. In the present work gaseous hydrogen is considered as fuel. This study was mainly focused on the mixing characteristics of four different fuel injection locations. It was found that injecting fuel upstream of the ramp was beneficial from fuel spread point of view.

  7. Linac pre-injector

    CERN Multimedia

    CERN PhotoLab

    1965-01-01

    New accelerating column of the linac pre-injector, supporting frame and pumping system. This new system uses two mercury diffusion pumps (in the centre) and forms part of the modifications intended to increase the intensity of the linac. View taken during assembly in the workshop.

  8. Warm pre-stressing

    International Nuclear Information System (INIS)

    Hedner, G.

    1983-01-01

    Literature survey and critical evaluation of the phenomenon of warm pre-stressing (WPS) is presented. It is found that the cause of it is not clear and a calculated control is missing. The effect of irradiation is unknown, and the influence of WPS on the behaviour of reactor vessels is discussed. (G.B.)

  9. pre-art guidelines

    African Journals Online (AJOL)

    Enrique

    2004-11-01

    Nov 1, 2004 ... As these guidelines address pre-ART issues, only conditions that occur at ... All HIV-infected adults who are immunosuppressed, i.e. ... therefore recommended that HIV-infected health care ... vaccine in severely immunosuppressed persons, i.e. those ... with residual insecticides, the use of larvicides, and.

  10. Pre-calculus essentials

    CERN Document Server

    Woodward, Ernest

    2012-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Pre-Calculus reviews sets, numbers, operations and properties, coordinate geometry, fundamental algebraic topics, solving equations and inequalities, functions, trigonometry, exponents

  11. Pre-college education

    Science.gov (United States)

    Stein, Sylvia

    1990-01-01

    Pre-college education efforts are many and varied, involving the teachers, students, parents, museums, and youth groups. However, it is necessary to reach out to school administration at all levels if teachers are to be innovative in their approaches. This introductory meeting clearly indicated that more interaction between the participants would be profitable. It is clear that the science pipeline leading from kindergarten to college entry needs to be filled with students. What is not clear is how we can do it. The plethora of projects being pursued by the NASA Space Grant College Fellowship (NSGC) programs to accomplish that goal are heartening and exciting. However, this large gamut of programs may also indicate how new we are in this game and how little anyone knows about creating a pre-college interest in science and engineering. In a way, it resembles the situation of the common cold--there is no known cure yet, so there are many so-called remedies. Unfortunately, the time we had together was entirely too short to address the evaluation situation, so that we can in the future zero in on the most effective approaches. This report is a summary of the many ways the different NSGC' s are approaching pre-college education and a list of suggestions.

  12. Pre-metastatic niches

    DEFF Research Database (Denmark)

    Peinado, Héctor; Zhang, Haiying; Matei, Irina R.

    2017-01-01

    It is well established that organs of future metastasis are not passive receivers of circulating tumour cells, but are instead selectively and actively modified by the primary tumour before metastatic spread has even occurred. Sowing the 'seeds' of metastasis requires the action of tumour......-secreted factors and tumour-shed extracellular vesicles that enable the 'soil' at distant metastatic sites to encourage the outgrowth of incoming cancer cells. In this Review, we summarize the main processes and new mechanisms involved in the formation of the pre-metastatic niche....

  13. PRE-RETIREMENT PROGRAMME

    CERN Multimedia

    2001-01-01

    Special Meeting concerning the TAXATION OF PENSIONS IN FRANCE Following the pre-retirement seminar held at CERN in March 2001, the Human Resources Division and the CERN Pensioners Association (GAC) are organising a special information session on the Taxation of CERN pensions in France The speaker will be S. Agarrat, a barrister specialising in tax law (practising in Lyon) and the meeting will take the form of a general presentation of the subject, followed by a question-and-answer session. This meeting is intended for CERN pensioners residing in France, as well as for staff due to retire from the Organization in 2001/2002. Registration is not necessary. The meeting will take place on Wednesday, 28 November 2001, from 4.30 p.m. to 6.30 p.m., in the Main Auditorium N.B.: Questions concerning the taxation rules applicable to salaries paid by CERN, in particular questions relating to the CRDS tax, will not be dealt with during this meeting.

  14. Morphological characterization of pre- and peri-implantation in vitro cultured, somatic cell nuclear transfer and in vivo derived ovine embryos

    DEFF Research Database (Denmark)

    Tveden-Nyborg, Pernille Yde; Peura, T.T.; Hartwich, K.M.

    2005-01-01

    The processes of cellular differentiation were studied in somatic cell nuvlear transfer (SCNT), in vitro cultured (IVC) and in vivo developed (in vivo) ovine embryos on days 7, 9, 11, 13, 17 and 19. SCNT embryos were constructed from in vitro matured oocytes and granulosa cells, and IVC embryos...... were produced by in vitro culture of in vivo fertilized zygotes. Most SCNT and IVC embryos were transferred to recipients on day 6 while some remained in culture for day 7 processing. In vivo embryos were collected as zygotes, transferred to intermediate recipients and retransferred to final recipients...

  15. CHARACTERIZATIONS OF FUZZY SOFT PRE SEPARATION AXIOMS

    OpenAIRE

    El-Latif, Alaa Mohamed Abd

    2015-01-01

    − The notions of fuzzy pre open soft sets and fuzzy pre closed soft sets were introducedby Abd El-latif et al. [2]. In this paper, we continue the study on fuzzy soft topological spaces andinvestigate the properties of fuzzy pre open soft sets, fuzzy pre closed soft sets and study variousproperties and notions related to these structures. In particular, we study the relationship betweenfuzzy pre soft interior fuzzy pre soft closure. Moreover, we study the properties of fuzzy soft pre regulars...

  16. Pre-Calculus For Dummies

    CERN Document Server

    Kuang, Yang

    2012-01-01

    The fun and easy way to learn pre-calculus Getting ready for calculus but still feel a bit confused? Have no fear. Pre-Calculus For Dummies is an un-intimidating, hands-on guide that walks you through all the essential topics, from absolute value and quadratic equations to logarithms and exponential functions to trig identities and matrix operations. With this guide's help you'll quickly and painlessly get a handle on all of the concepts - not just the number crunching - and understand how to perform all pre-calc tasks, from graphing to tackling proofs. You'll also get a new appreciation for

  17. Review on pre-eclampsia

    OpenAIRE

    Schlembach, Dietmar

    2003-01-01

    Pre-eclampsia is still one of the leading causes of maternal and fetal morbidity and mortality. Despite active research for many decades, the etiology of this disorder exclusive to human pregnancy is an enigma. Recent evidence suggests there may be several underlying causes or predispositions leading to endothelial dysfunction and causing the signs of hypertension, proteinuria, and edema--findings that allow us to make the diagnosis of the "syndrome" of pre-eclampsia. It is obvious that a sin...

  18. Pre-prosthetic surgery: Mandible

    Directory of Open Access Journals (Sweden)

    Veeramalai Naidu Devaki

    2012-01-01

    Full Text Available Pre-prosthetic surgery is that part of oral and maxillofacial surgery which restores oral function and facial form. This is concerned with surgical modification of the alveolar process and its surrounding structures to enable the fabrication of a well-fitting, comfortable, and esthetic dental prosthesis. The ultimate goal of pre-prosthetic surgery is to prepare a mouth to receive a dental prosthesis by redesigning and smoothening bony edges.

  19. IRIS pre-application licensing

    International Nuclear Information System (INIS)

    Carelli, Mario D.; Kling, Charles L.; Ritterbusch, Stanley E.

    2003-01-01

    This paper presents the approach to pre-application licensing by the International Reactor Innovative and Secure (IRIS), and advanced, integral reactor design with a thermal power of 1000 MW. The rationale for the pre-application licensing is discussed. Since IRIS technology is based on proven LWR experience, the project will rely on AP600/AP1000 precedent and will focus during the pre-application on long lead and novel items. A discussion of the evolution of the project to significantly reduce licensing issues is provided, followed by a summary of the IRIS safety-by-design which provides a formidable first step in the Defense in Depth approach. The effects of the safety-by-design, as well as of passive systems, on the IRIS safety will be investigated in a proposed testing program that will be reviewed by NRC during the pre-application. Documentation to be provided to NRC is discussed. Early design analyses indicate that the benefits of the IRIS safety-by-design approach are so significant that the basic premise of current emergency planning regulations (i.e., likelihood of core damage) will be reduced to the extent that special emergency response planning beyond the exclusion area boundary may not be needed. How this very significant outcome can be effected through a highly risk-informed licensing is discussed. (author)

  20. Case Report of Left Retrocaval Ureter: Pre-Transplant CT Urographic Findings and Post-Transplant Outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ah Yeong; Park, Byung Kwan; Kim, Chan Kyo; Park, Sung Yoon; Han, Deok Hyun [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2013-02-15

    A left retrocaval ureter is an extremely rare congenital anomaly, in which the left ureter passes behind the left inferior vena cava (IVC). The compression of the ureter between the IVC and the vertebrae results in a progressive hydronephrosis. Recently, the left kidney with a retrocaval ureter was detected on CT urographic images in a living-related donor and achieved a good outcome after allograft transplantation. We report the CT urographic findings of a left retrocaval ureter and the short-term outcome of allograft transplantation.

  1. Pre-equilibrium gamma emissions

    International Nuclear Information System (INIS)

    Ghosh, Sudip

    1993-01-01

    Together with the direct reaction and the compound nuclear emissions the pre-equilibrium (PEQ) or pre-compound processes give a fairly complete picture of nuclear reactions induced by light ions at energies of some tens of MeV. PEQ particle emissions covering the higher energy continuum spectra have been investigated in detail both experimentally and theoretically. In contrast, very little work has been done on PEQ γ- emissions. The reason is that in spite of extensive work done on PEQ particle emissions, the mechanism is not yet fully understood. Also, the PEQ γ-emission cross-sections (∼ micro barns) are very small compared to the PEQ particle emission cross-sections (∼ milli barns). Yet apart from the academic interest the understanding of PEQ γ-emissions is important for applied fusion research etc. In this paper the PEQ γ-emissions is discussed and the work done in this field is reviewed. (author). 14 refs

  2. Pre-operative evaluation for thorax surgery

    International Nuclear Information System (INIS)

    Silva Luis, Saenz; Morales, Oscar Alberto

    2002-01-01

    A pre-operative analysis of the function of the breathing system is made in the patient that will be taken to thorax surgery. The paper includes risk factors, pre-operative clinical evaluation and of breathing and cardiovascular system

  3. JPP: A Java Pre-Processor

    OpenAIRE

    Kiniry, Joseph R.; Cheong, Elaine

    1998-01-01

    The Java Pre-Processor, or JPP for short, is a parsing pre-processor for the Java programming language. Unlike its namesake (the C/C++ Pre-Processor, cpp), JPP provides functionality above and beyond simple textual substitution. JPP's capabilities include code beautification, code standard conformance checking, class and interface specification and testing, and documentation generation.

  4. A pre-Hispanic head.

    Directory of Open Access Journals (Sweden)

    Raffaella Bianucci

    Full Text Available This report on a male head revealed biologic rhythms, as gleaned from hydrogen isotope ratios in hair, consistent with a South-American origin and Atomic Mass Spectrometry radiocarbon dating (AMS compatible with the last pre-Hispanic period (1418-1491 AD, 95.4% probability. Biopsies showed exceptionally well-preserved tissues. The hair contained high levels of toxic elements (lead, arsenic and mercury incompatible with life. There was no evidence for lead deposition in bone consistent with post-mortem accumulation of this toxic element in the hair. We propose that the high content of metals in hair was the result of metabolic activity of bacteria leading to metal complexation in extra cellular polymeric substances (EPS. This is a recognized protective mechanism for bacteria that thrive in toxic environments. This mechanism may account for the tissues preservation and gives a hint at soil composition where the head was presumably buried. Our results have implications for forensic toxicology which has, hitherto, relied on hair analyses as one means to reconstruct pre-mortem metabolism and for detecting toxic elements accumulated during life. Our finding also has implications for other archaeological specimens where similar circumstances may distort the results of toxicological studies.

  5. A pre-Hispanic head.

    Science.gov (United States)

    Bianucci, Raffaella; Jeziorska, Maria; Lallo, Rudy; Mattutino, Grazia; Massimelli, Massimo; Phillips, Genevieve; Appenzeller, Otto

    2008-04-30

    This report on a male head revealed biologic rhythms, as gleaned from hydrogen isotope ratios in hair, consistent with a South-American origin and Atomic Mass Spectrometry radiocarbon dating (AMS) compatible with the last pre-Hispanic period (1418-1491 AD, 95.4% probability). Biopsies showed exceptionally well-preserved tissues. The hair contained high levels of toxic elements (lead, arsenic and mercury) incompatible with life. There was no evidence for lead deposition in bone consistent with post-mortem accumulation of this toxic element in the hair. We propose that the high content of metals in hair was the result of metabolic activity of bacteria leading to metal complexation in extra cellular polymeric substances (EPS). This is a recognized protective mechanism for bacteria that thrive in toxic environments. This mechanism may account for the tissues preservation and gives a hint at soil composition where the head was presumably buried. Our results have implications for forensic toxicology which has, hitherto, relied on hair analyses as one means to reconstruct pre-mortem metabolism and for detecting toxic elements accumulated during life. Our finding also has implications for other archaeological specimens where similar circumstances may distort the results of toxicological studies.

  6. Pre-Algebra Essentials For Dummies

    CERN Document Server

    Zegarelli, Mark

    2010-01-01

    Many students worry about starting algebra. Pre-Algebra Essentials For Dummies provides an overview of critical pre-algebra concepts to help new algebra students (and their parents) take the next step without fear. Free of ramp-up material, Pre-Algebra Essentials For Dummies contains content focused on key topics only. It provides discrete explanations of critical concepts taught in a typical pre-algebra course, from fractions, decimals, and percents to scientific notation and simple variable equations. This guide is also a perfect reference for parents who need to review critical pre-algebra

  7. Hemostasis in pre-eclampsia.

    LENUS (Irish Health Repository)

    Ismail, Siti Khadijah

    2012-01-31

    Pre-eclampsia (P-EC) is a multisystem disorder exclusive to pregnancy. It complicates ~2 to 8% of all pregnancies and remains a major cause of maternal mortality. P-EC is characterized by a profound hypercoagulable state. The delicate hemostatic balance that must be maintained in the uteroplacental circulation during pregnancy makes this system vulnerable to perturbation. An abnormal hemostatic pattern occurs within the uteroplacental circulation in P-EC compared with normal pregnancy. Much recent research has focused on the epidemiological link between inherited thrombophilia and P-EC. The data suggest a weak statistical association, indicating an improbable primary role in the pathogenesis. Without clear evidence, low molecular weight heparins have been widely used to reduce recurrence of P-EC in thrombophilia-positive women. This practice now should be reviewed. Future research needs to focus on improving our basic scientific understanding of the role of the hemostatic system in human placentation.

  8. Hemostasis in pre-eclampsia.

    LENUS (Irish Health Repository)

    Ismail, Siti Khadijah

    2011-03-01

    Pre-eclampsia (P-EC) is a multisystem disorder exclusive to pregnancy. It complicates ~2 to 8% of all pregnancies and remains a major cause of maternal mortality. P-EC is characterized by a profound hypercoagulable state. The delicate hemostatic balance that must be maintained in the uteroplacental circulation during pregnancy makes this system vulnerable to perturbation. An abnormal hemostatic pattern occurs within the uteroplacental circulation in P-EC compared with normal pregnancy. Much recent research has focused on the epidemiological link between inherited thrombophilia and P-EC. The data suggest a weak statistical association, indicating an improbable primary role in the pathogenesis. Without clear evidence, low molecular weight heparins have been widely used to reduce recurrence of P-EC in thrombophilia-positive women. This practice now should be reviewed. Future research needs to focus on improving our basic scientific understanding of the role of the hemostatic system in human placentation.

  9. Pre-equilibrium plasma dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Heinz, U.

    1986-01-01

    Approaches towards understanding and describing the pre-equilibrium stage of quark-gluon plasma formation in heavy-ion collisions are reviewed. Focus is on a kinetic theory approach to non-equilibrium dynamics, its extension to include the dynamics of color degrees of freedom when applied to the quark-gluon plasma, its quantum field theoretical foundations, and its relationship to both the particle formation stage at the very beginning of the nuclear collision and the hydrodynamic stage at late collision times. The usefulness of this approach to obtain the transport coefficients in the quark-gluon plasma and to derive the collective mode spectrum and damping rates in this phase are discussed. Comments are made on the general difficulty to find appropriated initial conditions to get the kinetic theory started, and a specific model is given that demonstrates that, once given such initial conditions, the system can be followed all the way through into the hydrodynamical regime. 39 refs., 7 figs. (LEW)

  10. Pre-equilibrium plasma dynamics

    International Nuclear Information System (INIS)

    Heinz, U.

    1986-01-01

    Approaches towards understanding and describing the pre-equilibrium stage of quark-gluon plasma formation in heavy-ion collisions are reviewed. Focus is on a kinetic theory approach to non-equilibrium dynamics, its extension to include the dynamics of color degrees of freedom when applied to the quark-gluon plasma, its quantum field theoretical foundations, and its relationship to both the particle formation stage at the very beginning of the nuclear collision and the hydrodynamic stage at late collision times. The usefulness of this approach to obtain the transport coefficients in the quark-gluon plasma and to derive the collective mode spectrum and damping rates in this phase are discussed. Comments are made on the general difficulty to find appropriated initial conditions to get the kinetic theory started, and a specific model is given that demonstrates that, once given such initial conditions, the system can be followed all the way through into the hydrodynamical regime. 39 refs., 7 figs

  11. Pre-Assessment: Promises and Cautions

    Science.gov (United States)

    Guskey, Thomas R.; McTighe, Jay

    2016-01-01

    Nearly every modern instructional planning model, differentiation approach, and personalized learning system incorporates some form of re-assessment. Yet there's scant research evidence that teachers use pre-assessment in ways that improve learning, according to Guskey and McTighe. To increase the likelihood that pre-assessment will be worth the…

  12. Flashback resistant pre-mixer assembly

    Science.gov (United States)

    Laster, Walter R [Oviedo, FL; Gambacorta, Domenico [Oviedo, FL

    2012-02-14

    A pre-mixer assembly associated with a fuel supply system for mixing of air and fuel upstream from a main combustion zone in a gas turbine engine. The pre-mixer assembly includes a swirler assembly disposed about a fuel injector of the fuel supply system and a pre-mixer transition member. The swirler assembly includes a forward end defining an air inlet and an opposed aft end. The pre-mixer transition member has a forward end affixed to the aft end of the swirler assembly and an opposed aft end defining an outlet of the pre-mixer assembly. The aft end of the pre-mixer transition member is spaced from a base plate such that a gap is formed between the aft end of the pre-mixer transition member and the base plate for permitting a flow of purge air therethrough to increase a velocity of the air/fuel mixture exiting the pre-mixer assembly.

  13. Slovenian Pre-Service Teachers' Prototype Biography

    Science.gov (United States)

    Lipovec, Alenka; Antolin, Darja

    2014-01-01

    In this article we apply narrative methodology to the study of pre-service elementary teachers' school-time memories connected to mathematics education. In the first phase of our empirical study we asked 214 Slovenian pre-service teachers to write their mathematical autobiographies. On the basis of the mathematical autobiographies we constructed a…

  14. Pre-Service Teachers' Conceptions of Probability

    Science.gov (United States)

    Odafe, Victor U.

    2011-01-01

    Probability knowledge and skills are needed in science and in making daily decisions that are sometimes made under uncertain conditions. Hence, there is the need to ensure that the pre-service teachers of our children are well prepared to teach probability. Pre-service teachers' conceptions of probability are identified, and ways of helping them…

  15. Pre-cementation of deep shaft

    Science.gov (United States)

    Heinz, W. F.

    1988-12-01

    Pre-cementation or pre-grouting of deep shafts in South Africa is an established technique to improve safety and reduce water ingress during shaft sinking. The recent completion of several pre-cementation projects for shafts deeper than 1000m has once again highlighted the effectiveness of pre-grouting of shafts utilizing deep slimline boreholes and incorporating wireline technique for drilling and conventional deep borehole grouting techniques for pre-cementation. Pre-cementation of deep shaft will: (i) Increase the safety of shaft sinking operation (ii) Minimize water and gas inflow during shaft sinking (iii) Minimize the time lost due to additional grouting operations during sinking of the shaft and hence minimize costly delays and standing time of shaft sinking crews and equipment. (iv) Provide detailed information of the geology of the proposed shaft site. Informations on anomalies, dykes, faults as well as reef (gold bearing conglomerates) intersections can be obtained from the evaluation of cores of the pre-cementation boreholes. (v) Provide improved rock strength for excavations in the immediate vicinity of the shaft area. The paper describes pre-cementation techniques recently applied successfully from surface and some conclusions drawn for further considerations.

  16. Areas and Volumes in Pre-Calculus

    Science.gov (United States)

    Jarrett, Joscelyn A.

    2008-01-01

    This article suggests the introduction of the concepts of areas bounded by plane curves and the volumes of solids of revolution in Pre-calculus. It builds on the basic knowledge that students bring to a pre-calculus class, derives a few more formulas, and gives examples of some problems on plane areas and the volumes of solids of revolution that…

  17. Probing the pre-big bang universe

    International Nuclear Information System (INIS)

    Veneziano, G.

    2000-01-01

    Superstring theory suggests a new cosmology whereby a long inflationary phase preceded a non singular big bang-like event. After discussing how pre-big bang inflation naturally arises from an almost trivial initial state of the Universe, I will describe how present or near-future experiments can provide sensitive probes of how the Universe behaved in the pre-bang era

  18. The Pre-IPO Dividend Puzzle

    NARCIS (Netherlands)

    Martin, J.; Zeckhauser, R.

    2011-01-01

    We investigate dividend payments of companies prior to their IPOs. U.S. companies conducting an IPO between 1990 through 2006 comprise our sample. Pre-IPO dividend payments are significant both in number and size in the quarter leading up to the IPO. We find support for the hypothesis that pre-IPO

  19. Pre-K as School Turnaround Strategy

    Science.gov (United States)

    Buenafe, Anthony Q.

    2011-01-01

    Both state and local school systems, recognizing the strong and growing evidence of pre-kindergarten's effectiveness in closing achievement gaps, are implementing early learning programs as part of their education reform efforts. In low-performing districts, pre-k has emerged as a promising turnaround strategy, reaching children before they become…

  20. Developing Pre-service Teachers' Technology Integration ...

    African Journals Online (AJOL)

    Developing Pre-service Teachers' Technology Integration Competencies in Science and Mathematics Teaching: Experiences from Tanzania and Uganda. ... This study investigated the ICT integration practices in pre-service teacher education in the School of Education at Makerere University (College of Education and ...

  1. PRE: A framework for enterprise integration

    Energy Technology Data Exchange (ETDEWEB)

    Whiteside, R.A.; Friedman-Hill, E.J. [Sandia National Labs., Livermore, CA (United States); Detry, R.J. [Sandia National Labs., Albuquerque, NM (United States)

    1998-03-01

    Sandia National Laboratories` Product Realization Environment (PRE) is a lightweight, CORBA based framework for the integration of a broad variety of applications. These applications are wrapped for use in the PRE framework as reusable components. For example, some of the PRE components currently available include: (1) product data management (PDM) system, (2) human resources database, several finite element analysis programs, and (3) a variety of image and document format converters. PRE enables the development of end user applications (as Java applets, for example) that use these components as building blocks. To aid such development, the PreLib library (available in both C++ and Java) permits both wrapping and using these components without knowledge of either CORBA or the security mechanisms used.

  2. Pre-task music improves swimming performance.

    Science.gov (United States)

    Smirmaul, B P; Dos Santos, R V; Da Silva Neto, L V

    2015-12-01

    The purpose of this study was to investigate the effects of pre-task music on swimming performance and other psychological variables. A randomized counterbalanced within-subjects (experimental and control condition) design was employed. Eighteen regional level male swimmers performed two 200-m freestyle swimming time trials. Participants were exposed to either 5 minutes of self-selected music (pre-task music condition) or 5 minutes of silence (control condition) and, after 1 minute, performed the swimming task. Swimming time was significantly shorter (-1.44%) in the pre-task music condition. Listening to pre-task music increased motivation to perform the swimming task, while arousal remained unchanged. While fatigue increased after the swimming task in both conditions, vigor, ratings of perceived exertion and affective valence were unaltered. It is concluded, for the first time, that pre-task music improves swimming performance.

  3. Comparing the IRT Pre-equating and Section Pre-equating: A Simulation Study.

    Science.gov (United States)

    Hwang, Chi-en; Cleary, T. Anne

    The results obtained from two basic types of pre-equatings of tests were compared: the item response theory (IRT) pre-equating and section pre-equating (SPE). The simulated data were generated from a modified three-parameter logistic model with a constant guessing parameter. Responses of two replication samples of 3000 examinees on two 72-item…

  4. Pre-symptomatic increase in urine-orosomucoid excretion in pre-eclamptic women

    DEFF Research Database (Denmark)

    Kronborg, Camilla Skovhus; Allen, Jim; Vittinghus, Erik

    2007-01-01

    , 32 women developed pre-eclampsia, and 5 controls for every case of pre-eclampsia were found. Blood samples were collected 4 times and urine samples 6 times from the 18/19th week and throughout pregnancy. Orosomucoid and albumin in plasma were analysed by standard methods, and in urine by sandwich...... in orosomucoid. In the plasma samples, orosomucoid was significantly higher late in pre-eclamptic pregnancies (>or=36th week, p=0.0275). CONCLUSIONS: Pre-eclampsia is associated with a pre-symptomatic increase in the urine excretion of orosomucoid, and orosomucoid excretion precedes that of albumin. Orosomucoid...... excretion can probably be used as a prognostic tool in combination with other screening methods, and seems to be a more sensitive marker for evolving pre-eclampsia than albumin. Plasma orosomucoid is significantly increased late in pre-eclampsia. Thus, the increased excretion of orosomucoid must primarily...

  5. Pre-inflation physics and scalar perturbations

    International Nuclear Information System (INIS)

    Hirai, Shiro

    2005-01-01

    The effect of pre-inflation physics on the power spectrum of scalar perturbations is investigated. Considering various pre-inflation models with radiation-dominated or matter-dominated periods before inflation, the power spectra of curvature perturbations for large scales are calculated, and the spectral index and running spectral index are derived. It is shown that pre-inflation models in which the length of inflation is near 60 e-folds may reproduce some key properties implied by the Wilkinson microwave anisotropy probe data

  6. Pre-Trip Notification Database (PTNS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The PTNS contains pre-trip notification data from vessels participating in the Northeast Multispecies groundfish fishery from 2010 to present and the Longfin squid...

  7. Understanding Pre-Quantitative Risk in Projects

    Science.gov (United States)

    Cooper, Lynne P.

    2011-01-01

    Standard approaches to risk management in projects depend on the ability of teams to identify risks and quantify the probabilities and consequences of these risks (e.g., the 5 x 5 risk matrix). However, long before quantification does - or even can - occur, and long after, teams make decisions based on their pre-quantitative understanding of risk. These decisions can have long-lasting impacts on the project. While significant research has looked at the process of how to quantify risk, our understanding of how teams conceive of and manage pre-quantitative risk is lacking. This paper introduces the concept of pre-quantitative risk and discusses the implications of addressing pre-quantitative risk in projects.

  8. Pre-Existing Condition Insurance Plan Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Affordable Care Act created the new Pre-Existing Condition Insurance Plan (PCIP) program to make health insurance available to Americans denied coverage by...

  9. Coverage for SCS Pre-1941 Aerial Photography

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This shapefile was generated by the U.S. Bureau of Land Management (BLM) at the New Mexico State Office to show the coverage for the Pre-1941 aerial photography...

  10. Practical Secure Computation with Pre-Processing

    DEFF Research Database (Denmark)

    Zakarias, Rasmus Winther

    Secure Multiparty Computation has been divided between protocols best suited for binary circuits and protocols best suited for arithmetic circuits. With their MiniMac protocol in [DZ13], Damgård and Zakarias take an important step towards bridging these worlds with an arithmetic protocol tuned...... space for pre-processing material than computing the non-linear parts online (depends on the quality of circuit of course). Surprisingly, even for our optimized AES-circuit this is not the case. We further improve the design of the pre-processing material and end up with only 10 megabyes of pre...... a protocol for small field arithmetic to do fast large integer multipli- cations. This is achieved by devising pre-processing material that allows the Toom-Cook multiplication algorithm to run between the parties with linear communication complexity. With this result computation on the CPU by the parties...

  11. Cosmological imprints of pre-inflationary particles

    Energy Technology Data Exchange (ETDEWEB)

    Fialkov, Anastasia; Itzhaki, Nissan; Kovetz, Ely D., E-mail: anastasia.fialkov@gmail.com, E-mail: nitzhaki@post.tau.ac.il, E-mail: elykovetz@gmail.com [Tel-Aviv University, Ramat-Aviv, 69978 (Israel)

    2010-02-01

    We study some of the cosmological imprints of pre-inflationary particles. We show that each such particle provides a seed for a spherically symmetric cosmic defect. The profile of this cosmic defect is fixed and its magnitude is linear in a single parameter that is determined by the mass of the pre-inflationary particle. We study the CMB and peculiar velocity imprints of this cosmic defect and suggest that it could explain some of the large scale cosmological anomalies.

  12. Cosmological imprints of pre-inflationary particles

    International Nuclear Information System (INIS)

    Fialkov, Anastasia; Itzhaki, Nissan; Kovetz, Ely D.

    2010-01-01

    We study some of the cosmological imprints of pre-inflationary particles. We show that each such particle provides a seed for a spherically symmetric cosmic defect. The profile of this cosmic defect is fixed and its magnitude is linear in a single parameter that is determined by the mass of the pre-inflationary particle. We study the CMB and peculiar velocity imprints of this cosmic defect and suggest that it could explain some of the large scale cosmological anomalies

  13. Thermodynamic Analysis of Three Compressed Air Energy Storage Systems: Conventional, Adiabatic, and Hydrogen-Fueled

    Directory of Open Access Journals (Sweden)

    Hossein Safaei

    2017-07-01

    Full Text Available We present analyses of three families of compressed air energy storage (CAES systems: conventional CAES, in which the heat released during air compression is not stored and natural gas is combusted to provide heat during discharge; adiabatic CAES, in which the compression heat is stored; and CAES in which the compression heat is used to assist water electrolysis for hydrogen storage. The latter two methods involve no fossil fuel combustion. We modeled both a low-temperature and a high-temperature electrolysis process for hydrogen production. Adiabatic CAES (A-CAES with physical storage of heat is the most efficient option with an exergy efficiency of 69.5% for energy storage. The exergy efficiency of the conventional CAES system is estimated to be 54.3%. Both high-temperature and low-temperature electrolysis CAES systems result in similar exergy efficiencies (35.6% and 34.2%, partly due to low efficiency of the electrolyzer cell. CAES with high-temperature electrolysis has the highest energy storage density (7.9 kWh per m3 of air storage volume, followed by A-CAES (5.2 kWh/m3. Conventional CAES and CAES with low-temperature electrolysis have similar energy densities of 3.1 kWh/m3.

  14. Design of a reconfigurable liquid hydrogen fuel tank for use in the Genii unmanned aerial vehicle

    International Nuclear Information System (INIS)

    Adam, Patrick; Leachman, Jacob

    2014-01-01

    Long endurance flight, on the order of days, is a leading flight performance characteristic for Unmanned Aerial Vehicles (UAVs). Liquid hydrogen (LH2) is well suited to providing multi-day flight times with a specific energy 2.8 times that of conventional kerosene based fuels. However, no such system of LH2 storage, delivery, and use is currently available for commercial UAVs. In this paper, we develop a light weight LH2 dewar for integration and testing in the proton exchange membrane (PEM) fuel cell powered, student designed and constructed, Genii UAV. The fuel tank design is general for scaling to suit various UAV platforms. A cylindrical vacuum-jacketed design with removable end caps was chosen to incorporate various fuel level gauging, pressurizing, and slosh mitigation systems. Heat and mechanical loadings were modeled to compare with experimental results. Mass performance of the fuel tank is characterized by the fraction of liquid hydrogen to full tank mass, and the insulation performance was characterized by effective thermal conductivity and boil-off rate

  15. Design of a reconfigurable liquid hydrogen fuel tank for use in the Genii unmanned aerial vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Adam, Patrick; Leachman, Jacob [HYdrogen Properties for Energy Research (HYPER) Laboratory, Washington State University, Pullman, WA 99164-2920 (United States)

    2014-01-29

    Long endurance flight, on the order of days, is a leading flight performance characteristic for Unmanned Aerial Vehicles (UAVs). Liquid hydrogen (LH2) is well suited to providing multi-day flight times with a specific energy 2.8 times that of conventional kerosene based fuels. However, no such system of LH2 storage, delivery, and use is currently available for commercial UAVs. In this paper, we develop a light weight LH2 dewar for integration and testing in the proton exchange membrane (PEM) fuel cell powered, student designed and constructed, Genii UAV. The fuel tank design is general for scaling to suit various UAV platforms. A cylindrical vacuum-jacketed design with removable end caps was chosen to incorporate various fuel level gauging, pressurizing, and slosh mitigation systems. Heat and mechanical loadings were modeled to compare with experimental results. Mass performance of the fuel tank is characterized by the fraction of liquid hydrogen to full tank mass, and the insulation performance was characterized by effective thermal conductivity and boil-off rate.

  16. Developing RCM Strategy for Hydrogen Fuel Cells Utilizing On Line E-Condition Monitoring

    International Nuclear Information System (INIS)

    Baglee, D; Knowles, M J

    2012-01-01

    Fuel cell vehicles are considered to be a viable solution to problems such as carbon emissions and fuel shortages for road transport. Proton Exchange Membrane (PEM) Fuel Cells are mainly used in this purpose because they can run at low temperatures and have a simple structure. Yet high maintenance costs and the inherent dangers of maintaining equipment using hydrogen are two main issues which need to be addressed. The development of appropriate and efficient strategies is currently lacking with regard to fuel cell maintenance. A Reliability Centered Maintenance (RCM) approach offers considerable benefit to the management of fuel cell maintenance since it includes an identification and consideration of the impact of critical components. Technological developments in e-maintenance systems, radio-frequency identification (RFID) and personal digital assistants (PDAs) have proven to satisfy the increasing demand for improved reliability, efficiency and safety. RFID technology is used to store and remotely retrieve electronic maintenance data in order to provide instant access to up-to-date, accurate and detailed information. The aim is to support fuel cell maintenance decisions by developing and applying a blend of leading-edge communications and sensor technology including RFID. The purpose of this paper is to review and present the state of the art in fuel cell condition monitoring and maintenance utilizing RCM and RFID technologies. Using an RCM analysis critical components and fault modes are identified. RFID tags are used to store the critical information, possible faults and their cause and effect. The relationship between causes, faults, symptoms and long term implications of fault conditions are summarized. Finally conclusions are drawn regarding suggested maintenance strategies and the optimal structure for an integrated, cost effective condition monitoring and maintenance management system.

  17. Safety and operations of hydrogen fuel infrastructure in northern climates : a collaborative complex systems approach.

    Science.gov (United States)

    2010-10-07

    "This project examined the safety and operation of hydrogen (H2) fueling system infrastructure in : northern climates. A multidisciplinary team lead by the University of Vermont (UVM), : combined with investigators from Zhejiang and Tsinghua Universi...

  18. Calibrating the social value of prospective new goods: The case of hydrogen fuel cell electric Vehicles

    Science.gov (United States)

    Topel, Robert H.

    2018-01-01

    Economic studies of the value of a new good or product innovation are typically retrospective: after a new good has been developed and marketed to consumers, data on prices and consumer choices can be used to estimate welfare gains. This paper calibrates the prospective welfare gains in the United States from a nascent vehicle platform, fuel cell electric vehicles (FCVs), that may or may not succeed in competition with existing vehicle platforms. Prospective gains are due to three main sources: (1) possibly reduced carbon emissions compared to existing vehicle alternatives; (2) the monopsony benefit to the U.S. from reducing world oil demand and hence the price of oil; (3) national security benefits due to reduced "oil dependence", mitigating the impact of oil price shocks on national income. I find that the benefits of reduced carbon emissions are likely to be quite small because reduced oil demand in the U.S. as only a small impact on world oil consumption and carbon emissions. Net monopsony benefits to U.S. consumers are much larger.

  19. Energy pathway analysis - a hydrogen fuel cycle framework for system studies

    International Nuclear Information System (INIS)

    Badin, J.S.; Tagore, S.

    1997-01-01

    An analytical framework has been developed that can be used to estimate a range of life-cycle costs and impacts that result from the incremental production, storage, transport, and use of different fuels or energy carriers, such as hydrogen, electricity, natural gas, and gasoline. This information is used in a comparative analysis of energy pathways. The pathways provide the U.S. Department of Energy (DOE) with an indication of near-, mid-, and long-term technologies that have the greatest potential for advancement and can meet the cost goals. The methodology and conceptual issues are discussed. Also presented are results for selected pathways from the E3 (Energy, Economics, Emissions) Pathway Analysis Model. This model will be expanded to consider networks of pathways and to be compatible with a linear programming optimization processor. Scenarios and sets of constraints (energy demands, sources, emissions) will be defined so the effects on energy transformation activities included in the solution and on the total optimized system cost can be investigated. This evaluation will be used as a guide to eliminate technically feasible pathways if they are not cost effective or do not meet the threshold requirements for the market acceptance. (Author)

  20. The production of hydrogen fuel from renewable sources and its role in grid operations

    International Nuclear Information System (INIS)

    Barton, John; Gammon, Rupert

    2010-01-01

    Understanding the scale and nature of hydrogen's potential role in the development of low carbon energy systems requires an examination of the operation of the whole energy system, including heat, power, industrial and transport sectors, on an hour-by-hour basis. The Future Energy Scenario Assessment (FESA) software model used for this study is unique in providing a holistic, high resolution, functional analysis, which incorporates variations in supply resulting from weather-dependent renewable energy generators. The outputs of this model, arising from any given user-definable scenario, are year round supply and demand profiles that can be used to assess the market size and operational regime of energy technologies. FESA was used in this case to assess what - if anything - might be the role for hydrogen in a low carbon economy future for the UK. In this study, three UK energy supply pathways were considered, all of which reduce greenhouse gas emissions by 80% by 2050, and substantially reduce reliance on oil and gas while maintaining a stable electricity grid and meeting the energy needs of a modern economy. All use more nuclear power and renewable energy of all kinds than today's system. The first of these scenarios relies on substantial amounts of 'clean coal' in combination with intermittent renewable energy sources by year the 2050. The second uses twice as much intermittent renewable energy as the first and virtually no coal. The third uses 2.5 times as much nuclear power as the first and virtually no coal. All scenarios clearly indicate that the use of hydrogen in the transport sector is important in reducing distributed carbon emissions that cannot easily be mitigated by Carbon Capture and Storage (CCS). In the first scenario, this hydrogen derives mainly from steam reformation of fossil fuels (principally coal), whereas in the second and third scenarios, hydrogen is made mainly by electrolysis using variable surpluses of low-carbon electricity. Hydrogen thereby fulfils a double facetted role of Demand Side Management (DSM) for the electricity grid and the provision of a 'clean' fuel, predominantly for the transport sector. When each of the scenarios was examined without the use of hydrogen as a transport fuel, substantially larger amounts of primary energy were required in the form of imported coal. The FESA model also indicates that the challenge of grid balancing is not a valid reason for limiting the amount of intermittent renewable energy generated. Engineering limitations, economic viability, local environmental considerations and conflicting uses of land and sea may limit the amount of renewable energy available, but there is no practical limit to the conversion of this energy into whatever is required, be it electricity, heat, motive power or chemical feedstocks. (author)

  1. Appendix B: Hydrogen, Fuel Cells, and Infrastructure Technologies Program inputs for FY 2008 benefits estimates

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2009-01-18

    Document summarizes the results of the benefits analysis of EERE’s programs, as described in the FY 2008 Budget Request. EERE estimates benefits for its overall portfolio and nine Research, Development, Demonstration, and Deployment (RD3) programs.

  2. Developing a Model Using Homer for a Hybrid Hydrogen Fuel Cell System

    Directory of Open Access Journals (Sweden)

    Fera Annisa

    2013-04-01

    Full Text Available ABSTRACT. Hydrogen is widely considered be the fuel of the near future. Combined wind/PV energy hybrid systems can be used to sources energy to hydrogen production. This paper describes design, simulation and feasibility study of a hybrid energy system for a household in Malaysia. One year recorded wind speed and solar radiation are used for the design of a hybrid energy system. In 2000 was average annual wind speed in Johor Bahru is 3.76 m/s and annual average solar energy resource available is 5.08 kWh/m2/day. National Renewable Energy Laboratory’s HOMER software was used to select an optimum hybrid energy system. In the optimization process, HOMER simulates every system configuration in the search space and displays the feasible ones in a table, sorted by total net present cost (TNPC. The optimization study indicates that sensitivity analysis of the HOMER is shown in the overall winner which shows that the most least cost and optimize hybrid system is combination of 10 kW of PV array, 1 unit of wind turbine, 2 kW of fuel cell, 120 units of batteries and 6 kW converter as well as 1 kW of electrolyzer so as to generate the minimum COE, $2.423 kWh- 1. Although renewable sources (wind and PV involved in the power generation, 1 kg of hydrogen was produced in this system. Pengembangan Model Dengan Menggunakan Homer Untuk Sistem Sel Berbahan bakar Hidrogen Hibrida ABSTRAK. Hidrogen secara luas dianggap sebagai bahan bakar masa depan. Gabungan sistem hibrida energi angin/fotovoltaik dapat digunakan untuk sumber energi produksi hidrogen. Makalah ini menjelaskan desain, simulasi dan studi kelayakan dari sistem energi hibrida untuk rumah tangga di Malaysia. Satu tahun kecepatan angin tercatat dan radiasi matahari digunakan untuk desain sistem energi hibrida. Pada tahun 2000 adalah kecepatan angin rata-rata tahunan di Johor Bahru 3.76 m/det dan rata-rata sumber daya energi surya tahunan yang tersedia adalah 5.08 kWjam/m2/ hari. Software HOMER digunakan untuk memilih sistem energi hybrida optimal. Dalam proses optimasi, HOMER mensimulasikan setiap konfigurasi sistem dalam ruang pencarian dan menampilkan yang layak dalam sebuah tabel, diurutkan berdasarkan total net present (TNPC. Studi optimasi menunjukkan bahwa analisis sensitivitas HOMER ditampilkan dalam hasil keseluruhan yang menunjukkan bahwa paling sedikit biaya dan mengoptimalkan sistem hibrida adalah kombinasi dari 10 kW array PV, 1 unit turbin angin, 2 kW bahan bakar, 120 unit baterai dan 6 kW converter serta 1 kW electrolyzer sehingga menghasilkan COE(cost of energy minimal, $2,423 kWjam-1. Sumber-sumber terbarukan (angin dan PV yang terlibat dalam pembangkit listrik, 1 kg hydrogen akan diproduksi dalam sistem ini

  3. Porous Composite for Bipolar Plate in Low Emission Hydrogen Fuel Cells

    Directory of Open Access Journals (Sweden)

    Renata Katarzyna Włodarczyk

    2018-01-01

    Full Text Available The paper presents the results of graphite-stainless steel composites for the bipolar plates in low-temperature fuel cells. The sinters were performed by powder metallurgy technology. The influenceof technological parameters, especially molding pressure were examined. Following the requirements formulated by the DOE concerning the parameters of the materials, it indicated by the value of the parameters. The density, flowabilit, particle size of graphite and stainless steel powders have been evaluated. Composites have been tested by microstructure and phase analysis, properties of strength, functional properties: wettability, porosity, roughness. The special attention was paid to the analysis of corrosion resistance obtained sinters and influenceof technological parameters on the corrosion. Corrosion tests were carried out under conditions simulating the environment of the fuel cell under anode and cathode conditions. The effectof pH solution during working of the cell on corrosion resistance of composites have been evaluated. Contact resistance depends on roughness of sinters. Low ICR determined high contact area GDL-BP and high electrical conductivity on the contact surface. The ICR in anode conditions after corrosion tests are not change significantly; composite materials can be used for materials for B in terms of H 2 .

  4. The Development of Lifecycle Data for Hydrogen Fuel Production and Delivery

    Science.gov (United States)

    2017-10-01

    An evaluation of renewable hydrogen production technologies anticipated to be available in the short, mid- and long-term timeframes was conducted. Renewable conversion pathways often rely on a combination of renewable and fossil energy sources, with ...

  5. Hydrogen Storage Experiments for an Undergraduate Laboratory Course--Clean Energy: Hydrogen/Fuel Cells

    Science.gov (United States)

    Bailey, Alla; Andrews, Lisa; Khot, Ameya; Rubin, Lea; Young, Jun; Allston, Thomas D.; Takacs, Gerald A.

    2015-01-01

    Global interest in both renewable energies and reduction in emission levels has placed increasing attention on hydrogen-based fuel cells that avoid harm to the environment by releasing only water as a byproduct. Therefore, there is a critical need for education and workforce development in clean energy technologies. A new undergraduate laboratory…

  6. Advantages of the use of hydrogen fuel as compared to kerosene

    International Nuclear Information System (INIS)

    Koroneos, C.; Dompros, A.; Roumbas, G.; Moussiopoulos, N.

    2005-01-01

    A life cycle assessment (LCA) study has been carried out to investigate the environmental aspects of two types of aviation fuel, kerosene that is presently used and hydrogen. Hydrogen is selected as a future aircraft fuel because of the absence of CO 2 emissions from its use, its high energy content and its combustion kinetics. The life cycle of aviation fuel includes the production and the use of the aviation fuel in different types of aircraft. Hydrogen production by natural gas steam reforming and production upon renewable energy sources (RES) are examined. A very large number of environmental burdens result from the operation of the different fuel cycles. Air pollution is by far the biggest environmental problem that is resulting from hydrogen and kerosene production and use. This work has been mainly concentrated with this environmental impact category. It is shown that the production of hydrogen from RES has significantly lower environmental impact as compared to that of kerosene. However, the use of different RES carries different environmental impacts among them. The production of hydrogen resulting from the use of photovoltaics to capture solar energy carries the biggest environmental impact among the other RES, wind, hydropower, biomass and solar thermal

  7. The next generation of CANDU technologies: profiling the potential for hydrogen fuel

    International Nuclear Information System (INIS)

    Hopwood, J.M.

    2001-01-01

    This report discusses the Next-generation CANDU Power Reactor technologies currently under development at AECL. The innovations introduced into proven CANDU technologies include a compact reactor core design, which reduces the size by a factor of one third for the same power output; improved thermal efficiency through higher-pressure steam turbines; reduced use of heavy water (one quarter of the heavy water required for existing plants), thus reducing the cost and eliminating many material handling concerns; use of slightly enriched uranium to extend fuel life to three times that of existing natural uranium fuel and additions to CANDU's inherent passive safety. With these advanced features, the capital cost of constructing the plant can be reduced by up to 40 per cent compared to existing designs. The clean, affordable CANDU-generated electricity can be used to produce hydrogen for fuel cells for the transportation sector, thereby reducing emissions from the transportation sector

  8. Experimental analysis and management issues of a hydrogen fuel cell system for stationary and mobile application

    Energy Technology Data Exchange (ETDEWEB)

    Corbo, Pasquale; Migliardini, Fortunato; Veneri, Ottorino [Istituto Motori of Italian National Research Council, Via Marconi 8, 80125 Napoli (Italy)

    2007-08-15

    A laboratory fuel cell system based on a 20 kW H{sub 2}/air proton exchange membrane stack was designed, realized and characterized with the aim to elucidate specific concerns to be considered for both hydrogen stationary power systems and automotive applications. The overall system characterization permitted the effect of the main operative variables (temperature, pressure and stoichiometric ratio) on stack power and efficiency to be evaluated. Reactant feeding, humidification and cooling problems are discussed, evidencing in particular the roles of air compressor, fuel purge, stack temperature and humidification strategy in system management. The characterization results are analyzed in terms of H{sub 2} consumption and available power, evidencing the energy losses of the individual fuel cell system components. In particular, the data obtained on key components (stack, reactants, heat and water management devices) are used for a critical discussion about their specifications and operation characteristics as demanded by both stationary and mobile applications. (author)

  9. Global analysis and parametric dependencies for potential unintended hydrogen-fuel releases

    Energy Technology Data Exchange (ETDEWEB)

    Harstad, Kenneth; Bellan, Josette [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, M/S 125-109, Pasadena, CA 91109-8099 (United States)

    2006-01-01

    Global, simplified analyses of gaseous-hydrogen releases from a high-pressure vessel and liquid-hydrogen pools are conducted for two purposes: (1) establishing order-of-magnitude values of characteristic times and (2) determining parametric dependencies of these characteristic times on the physical properties of the configuration and on the thermophysical properties of hydrogen. According to the ratio of the characteristic release time to the characteristic mixing time, two limiting configurations are identified: (1) a rich cloud exists when this ratio is much smaller than unity, and (2) a jet exists when this ratio is much larger than unity. In all cases, it is found that the characteristic release time is proportional to the total released mass and inversely proportional to a characteristic area. The approximate size, convection velocity, and circulation time of unconfined burning-cloud releases scale with the cloud mass at powers 1/3, 1/6, and 1/6, respectively, multiplied by an appropriately dimensional constant; the influence of cross flow can only be important if its velocity exceeds that of internal convection. It is found that the fireball lifetime is approximately the maximum of the release time and thrice the convection-associated characteristic time. Transition from deflagration to detonation can occur only if the size of unconfined clouds exceeds by a factor of O(10) that of a characteristic detonation cell, which ranges from 0.015 m under stoichiometric conditions to approximately 1 m under extreme rich/lean conditions. For confined vapor pockets, transition occurs only for pocket sizes larger than the cell size. In jets, the release time is inversely proportional to the initial vessel pressure and has a square root dependence on the vessel temperature. Jet velocities are a factor of 10 larger than convective velocities in fireballs and combustion is possible only in the subsonic, downstream region where entrainment may occur.

  10. Hydrogen Fuel as Ecological Contribution to Operation of the Existing Coal-Fired Thermal Power Plants

    International Nuclear Information System (INIS)

    Cosic, D.

    2009-01-01

    The analysis is carried out of the application of a new hydrogen based alternative fuel as ecological contribution of the coal thermal power plants operation. Given the fact that coal thermal power plants are seen as the largest producers, not only of CO 2 , but of all others harmful gases, the idea is initiated to use the new alternative fuel as an additive to the coal which would result in much better performance of the coal power plants from an ecological point of view. It is possible to use such a fuel in relation of 10-30% of former coal use. The positive influence of such an application is much bigger than relative used quantity. This lecture has a goal to incite potential investors to create conditions for industrial testing of the new fuel. It will be very interesting to animate investors for large-scale production of the new fuel, too.(author).

  11. Mesoporous silicon synthesis and applications in Li-ion batteries and solar hydrogen fuel cells

    Science.gov (United States)

    Wang, Donghai; Dai, Fang; Yi, Ran; Zai, Jianto

    2017-05-23

    We provide a mesoporous silicon material (PSi) prepared via a template-free and HF-free process. The production process is facile and scalable, and it may be conducted under mild reaction conditions. The silicon may be produced directly by the reduction of a silicon-halogenide precursor (for example, SiCl.sub.4) with an alkaline alloy (for example, NaK alloy). The resulting Si-salt matrix is then annealed for the pore formation and crystallite growth. Final product is obtained by removal of the salt by-products with water.

  12. Comparison of ammonia and methanol applied indirectly in a hydrogen fuel cell

    International Nuclear Information System (INIS)

    Metkemeijer, R.; Achard, P.

    1993-01-01

    A comparison is presented between ammonia and methanol, applied indirectly in a hydrogen/air fuel cell. The calculations concentrate on specific energy of the fuels (amount of electricity produced per mass of fuel), specific energy of the fuels corrected for the mass and volume of the tank, and the overall energy efficiency (amount of electricity produced by one kg of fuel divided by the amount of energy needed for the production of one kg of this fuel). Taking into consideration the differences in efficiencies between the acid fuel cell and the alkaline fuel cells, the reformer temperatures, the reforming efficiencies, and some ecological and economical considerations, it appears that ammonia is a more interesting fuel than methanol for certain applications. 6 figs., 2 tabs

  13. Thermodynamic Cycle and CFD Analyses for Hydrogen Fueled Air-breathing Pulse Detonation Engines

    Science.gov (United States)

    Povinelli, Louis A.; Yungster, Shaye

    2002-01-01

    This paper presents the results of a thermodynamic cycle analysis of a pulse detonation engine (PDE) using a hydrogen-air mixture at static conditions. The cycle performance results, namely the specific thrust, fuel consumption and impulse are compared to a single cycle CFD analysis for a detonation tube which considers finite rate chemistry. The differences in the impulse values were indicative of the additional performance potential attainable in a PDE.

  14. Assessment of maximum available work of a hydrogen fueled compression ignition engine using exergy analysis

    International Nuclear Information System (INIS)

    Chintala, Venkateswarlu; Subramanian, K.A.

    2014-01-01

    This work is aimed at study of maximum available work and irreversibility (mixing, combustion, unburned, and friction) of a dual-fuel diesel engine (H 2 (hydrogen)–diesel) using exergy analysis. The maximum available work increased with H 2 addition due to reduction in irreversibility of combustion because of less entropy generation. The irreversibility of unburned fuel with the H 2 fuel also decreased due to the engine combustion with high temperature whereas there is no effect of H 2 on mixing and friction irreversibility. The maximum available work of the diesel engine at rated load increased from 29% with conventional base mode (without H 2 ) to 31.7% with dual-fuel mode (18% H 2 energy share) whereas total irreversibility of the engine decreased drastically from 41.2% to 39.3%. The energy efficiency of the engine with H 2 increased about 10% with 36% reduction in CO 2 emission. The developed methodology could also be applicable to find the effect and scope of different technologies including exhaust gas recirculation and turbo charging on maximum available work and energy efficiency of diesel engines. - Highlights: • Energy efficiency of diesel engine increases with hydrogen under dual-fuel mode. • Maximum available work of the engine increases significantly with hydrogen. • Combustion and unburned fuel irreversibility decrease with hydrogen. • No significant effect of hydrogen on mixing and friction irreversibility. • Reduction in CO 2 emission along with HC, CO and smoke emissions

  15. Developing RCM Strategy for Hydrogen Fuel Cells Utilizing On Line E-Condition Monitoring

    Science.gov (United States)

    Baglee, D.; Knowles, M. J.

    2012-05-01

    Fuel cell vehicles are considered to be a viable solution to problems such as carbon emissions and fuel shortages for road transport. Proton Exchange Membrane (PEM) Fuel Cells are mainly used in this purpose because they can run at low temperatures and have a simple structure. Yet high maintenance costs and the inherent dangers of maintaining equipment using hydrogen are two main issues which need to be addressed. The development of appropriate and efficient strategies is currently lacking with regard to fuel cell maintenance. A Reliability Centered Maintenance (RCM) approach offers considerable benefit to the management of fuel cell maintenance since it includes an identification and consideration of the impact of critical components. Technological developments in e-maintenance systems, radio-frequency identification (RFID) and personal digital assistants (PDAs) have proven to satisfy the increasing demand for improved reliability, efficiency and safety. RFID technology is used to store and remotely retrieve electronic maintenance data in order to provide instant access to up-to-date, accurate and detailed information. The aim is to support fuel cell maintenance decisions by developing and applying a blend of leading-edge communications and sensor technology including RFID. The purpose of this paper is to review and present the state of the art in fuel cell condition monitoring and maintenance utilizing RCM and RFID technologies. Using an RCM analysis critical components and fault modes are identified. RFID tags are used to store the critical information, possible faults and their cause and effect. The relationship between causes, faults, symptoms and long term implications of fault conditions are summarized. Finally conclusions are drawn regarding suggested maintenance strategies and the optimal structure for an integrated, cost effective condition monitoring and maintenance management system.

  16. Waste biomass toward hydrogen fuel supply chain management for electricity: Malaysia perspective

    Science.gov (United States)

    Zakaria, Izatul Husna; Ibrahim, Jafni Azhan; Othman, Abdul Aziz

    2016-08-01

    Green energy is becoming an important aspect of every country in the world toward energy security by reducing dependence on fossil fuel import and enhancing better life quality by living in the healthy environment. This conceptual paper is an approach toward determining physical flow's characteristic of waste wood biomass in high scale plantation toward producing gas fuel for electricity using gasification technique. The scope of this study is supply chain management of syngas fuel from wood waste biomass using direct gasification conversion technology. Literature review on energy security, Malaysia's energy mix, Biomass SCM and technology. This paper uses the theoretical framework of a model of transportation (Lumsden, 2006) and the function of the terminal (Hulten, 1997) for research purpose. To incorporate biomass unique properties, Biomass Element Life Cycle Analysis (BELCA) which is a novel technique develop to understand the behaviour of biomass supply. Theoretical framework used to answer the research questions are Supply Chain Operations Reference (SCOR) framework and Sustainable strategy development in supply chain management framework

  17. Experimental analysis and management issues of a hydrogen fuel cell system for stationary and mobile application

    International Nuclear Information System (INIS)

    Corbo, Pasquale; Migliardini, Fortunato; Veneri, Ottorino

    2007-01-01

    A laboratory fuel cell system based on a 20 kW H 2 /air proton exchange membrane stack was designed, realized and characterized with the aim to elucidate specific concerns to be considered for both hydrogen stationary power systems and automotive applications. The overall system characterization permitted the effect of the main operative variables (temperature, pressure and stoichiometric ratio) on stack power and efficiency to be evaluated. Reactant feeding, humidification and cooling problems are discussed, evidencing in particular the roles of air compressor, fuel purge, stack temperature and humidification strategy in system management. The characterization results are analyzed in terms of H 2 consumption and available power, evidencing the energy losses of the individual fuel cell system components. In particular, the data obtained on key components (stack, reactants, heat and water management devices) are used for a critical discussion about their specifications and operation characteristics as demanded by both stationary and mobile applications

  18. Multi-unit Inertial Fusion Energy (IFE) plants producing hydrogen fuel

    International Nuclear Information System (INIS)

    Logan, B.G.

    1993-12-01

    A quantitative energy pathway comparison is made between a modern oil refinery and genetic fusion hydrogen plant supporting hybrid-electric cars powered by gasoline and hydrogen-optimized internal combustion engines, respectively, both meeting President Clinton's goal for advanced car goal of 80 mpg gasoline equivalent. The comparison shows that a fusion electric plant producing hydrogen by water electrolysis at 80% efficiency must have an electric capacity of 10 GWe to support as many hydrogen-powered hybrid cars as one modern 200,000 bbl/day-capacity oil refinery could support in gasoline-powered hybrid cars. A 10 GWe fusion electric plant capital cost is limited to 12.5 B$ to produce electricity at 2.3 cents/kWehr, and hydrogen production by electrolysis at 8 $/GJ, for equal consumer fuel cost per passenger mile as in the oil-gasoline-hybrid pathway

  19. The production of hydrogen fuel from renewable sources and its role in grid operations

    Science.gov (United States)

    Barton, John; Gammon, Rupert

    Understanding the scale and nature of hydrogen's potential role in the development of low carbon energy systems requires an examination of the operation of the whole energy system, including heat, power, industrial and transport sectors, on an hour-by-hour basis. The Future Energy Scenario Assessment (FESA) software model used for this study is unique in providing a holistic, high resolution, functional analysis, which incorporates variations in supply resulting from weather-dependent renewable energy generators. The outputs of this model, arising from any given user-definable scenario, are year round supply and demand profiles that can be used to assess the market size and operational regime of energy technologies. FESA was used in this case to assess what - if anything - might be the role for hydrogen in a low carbon economy future for the UK. In this study, three UK energy supply pathways were considered, all of which reduce greenhouse gas emissions by 80% by 2050, and substantially reduce reliance on oil and gas while maintaining a stable electricity grid and meeting the energy needs of a modern economy. All use more nuclear power and renewable energy of all kinds than today's system. The first of these scenarios relies on substantial amounts of 'clean coal' in combination with intermittent renewable energy sources by year the 2050. The second uses twice as much intermittent renewable energy as the first and virtually no coal. The third uses 2.5 times as much nuclear power as the first and virtually no coal. All scenarios clearly indicate that the use of hydrogen in the transport sector is important in reducing distributed carbon emissions that cannot easily be mitigated by Carbon Capture and Storage (CCS). In the first scenario, this hydrogen derives mainly from steam reformation of fossil fuels (principally coal), whereas in the second and third scenarios, hydrogen is made mainly by electrolysis using variable surpluses of low-carbon electricity. Hydrogen thereby fulfils a double facetted role of Demand Side Management (DSM) for the electricity grid and the provision of a 'clean' fuel, predominantly for the transport sector. When each of the scenarios was examined without the use of hydrogen as a transport fuel, substantially larger amounts of primary energy were required in the form of imported coal. The FESA model also indicates that the challenge of grid balancing is not a valid reason for limiting the amount of intermittent renewable energy generated. Engineering limitations, economic viability, local environmental considerations and conflicting uses of land and sea may limit the amount of renewable energy available, but there is no practical limit to the conversion of this energy into whatever is required, be it electricity, heat, motive power or chemical feedstocks.

  20. Prediction of Combustion Stability and Flashback in Turbines with High-Hydrogen Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Lieuwen, Tim [Georgia Inst. of Technology, Atlanta, GA (United States); Santavicca, Dom [Georgia Inst. of Technology, Atlanta, GA (United States); Yang, Vigor [Georgia Inst. of Technology, Atlanta, GA (United States)

    2012-03-31

    During the duration of this sponsorship, we broadened our understanding of combustion instabilities through both analytical and experimental work. Predictive models were developed for flame response to transverse acoustic instabilities and for quantifying how a turbulent flame responds to velocity and fuel/air ratio forcing. Analysis was performed on the key instability mechanisms controlling heat release response for flames over a wide range of instability frequencies. Importantly, work was done closely with industrial partners to transition existing models into internal instability prediction codes. Experimentally, the forced response of hydrogen-enriched natural gas/air premixed and partially premixed flames were measured. The response of a lean premixed flame was investigated, subjected to velocity, equivalence ratio, and both forcing mechanisms simultaneously. In addition, important physical mechanisms controlling the response of partially premixed flames to inlet velocity and equivalence ratio oscillations were analyzed. This final technical report summarizes our findings and major publications stemming from this program.

  1. A hydrogen fuel cell for rapid, enzyme-catalysed organic synthesis with continuous monitoring.

    Science.gov (United States)

    Wan, Lei; Megarity, Clare F; Siritanaratkul, Bhavin; Armstrong, Fraser A

    2018-01-23

    A one-pot fuel cell for specific, enzyme-catalysed organic synthesis, with continuous monitoring of rate and reaction progress, combines an electrode catalysing rapid, reversible and diffusion-controlled interconversion of NADP + and NADPH with a Pt electrode catalysing 2H + /H 2 interconversion. This Communication demonstrates its performance and characteristics using the reductive amination of 2-oxoglutarate as a test system.

  2. Developing and Implementing a Simple, Affordable Hydrogen Fuel Cell Laboratory in Introductory Chemistry

    Science.gov (United States)

    Klara, Kristina; Hou, Ning; Lawman, Allison; Wu, Liheng; Morrill, Drew; Tente, Alfred; Wang, Li-Qiong

    2014-01-01

    A simple, affordable hydrogen proton exchange membrane (PEM) fuel cell laboratory was developed through a collaborative effort between faculty and undergraduate students at Brown University. It has been incorporated into the introductory chemistry curriculum and successfully implemented in a class of over 500 students per academic year for over 3…

  3. Hydrogen Fuel Cell Vehicle Fuel System Integrity Research : Electrical Isolation Test Procedure Development and Verification

    Science.gov (United States)

    2012-03-01

    The Federal Motor Vehicle Safety Standards (FMVSS) establish minimum levels for vehicle safety, and manufacturers of motor vehicle and equipment items must comply with these standards. The National Highway Traffic Safety Administration (NHTSA) contra...

  4. Oxygen-hydrogen fuel cell with an iodine-iodide cathode - A concept

    Science.gov (United States)

    Javet, P.

    1970-01-01

    Fuel cell uses a porous cathode through which is fed a solution of iodine in aqueous iodide solution, the anode is a hydrogen electrode. No activation polarization appears on the cathode because of the high exchange-current density of the iodine-iodide electrode.

  5. End of project report on degradation processes in hydrogen fuel cells.

    Science.gov (United States)

    2008-01-01

    Proton exchange membrane (PEM) fuel cells are one of the most popular types of fuel cells. They operate similarly to others with the electrolyte material inbetween the electrodes being a patented polymer called Nafion, made by DuPont. This polyelec...

  6. Hydrogen Fuel Cell Performance as Telecommunications Backup Power in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Jennifer [National Renewable Energy Lab. (NREL), Golden, CO (United States); Saur, Genevieve [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sprik, Sam [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-03-01

    Working in collaboration with the U.S. Department of Energy (DOE) and industry project partners, the National Renewable Energy Laboratory (NREL) acts as the central data repository for the data collected from real-world operation of fuel cell backup power systems. With American Recovery and Reinvestment Act of 2009 (ARRA) co-funding awarded through DOE's Fuel Cell Technologies Office, more than 1,300 fuel cell units were deployed over a three-plus-year period in stationary, material handling equipment, auxiliary power, and backup power applications. This surpassed a Fuel Cell Technologies Office ARRA objective to spur commercialization of an early market technology by installing 1,000 fuel cell units across several different applications, including backup power. By December 2013, 852 backup power units out of 1,330 fuel cell units deployed were providing backup service, mainly for telecommunications towers. For 136 of the fuel cell backup units, project participants provided detailed operational data to the National Fuel Cell Technology Evaluation Center for analysis by NREL's technology validation team. NREL analyzed operational data collected from these government co-funded demonstration projects to characterize key fuel cell backup power performance metrics, including reliability and operation trends, and to highlight the business case for using fuel cells in these early market applications. NREL's analyses include these critical metrics, along with deployment, U.S. grid outage statistics, and infrastructure operation.

  7. Novel catalysts for hydrogen fuel cell applications:Final report (FY03-FY05).

    Energy Technology Data Exchange (ETDEWEB)

    Thornberg, Steven Michael; Coker, Eric Nicholas; Jarek, Russell L.; Steen, William Arthur

    2005-12-01

    The goal of this project was to develop novel hydrogen-oxidation electrocatalyst materials that contain reduced platinum content compared to traditional catalysts by developing flexible synthesis techniques to fabricate supported catalyst structures, and by verifying electrochemical performance in half cells and ultimately laboratory fuel cells. Synthesis methods were developed for making small, well-defined platinum clusters using zeolite hosts, ion exchange, and controlled calcination/reduction processes. Several factors influence cluster size, and clusters below 1 nm with narrow size distribution have been prepared. To enable electrochemical application, the zeolite pores were filled with electrically-conductive carbon via infiltration with carbon precursors, polymerization/cross-linking, and pyrolysis under inert conditions. The zeolite host was then removed by acid washing, to leave a Pt/C electrocatalyst possessing quasi-zeolitic porosity and Pt clusters of well-controlled size. Plotting electrochemical activity versus pyrolysis temperature typically produces a Gaussian curve, with a peak at ca. 800 C. The poorer relative performances at low and high temperature are due to low electrical conductivity of the carbon matrix, and loss of zeolitic structure combined with Pt sintering, respectively. Cluster sizes measured via adsorption-based methods were consistently larger than those observed by TEM and EXAFS, suggesting , that a fraction of the clusters were inaccessible to the fluid phase. Detailed EXAFS analysis has been performed on selected catalysts and catalyst precursors to monitor trends in cluster size evolution, as well as oxidation states of Pt. Experiments were conducted to probe the electroactive surface area of the Pt clusters. These Pt/C materials had as much as 110 m{sup 2}/g{sub pt} electroactive surface area, an almost 30% improvement over what is commercially (mfg. by ETEK) available (86 m{sup 2}/g{sub pt}). These Pt/C materials also perform qualitatively as well as the ETEK material for the ORR, a non-trivial achievement. A fuel cell test showed that Pt/C outperformed the ETEK material by an average of 50% for a 300 hour test. Increasing surface area decreases the amount of Pt needed in a fuel cell, which translates into cost savings. Furthermore, the increased performance realized in the fuel cell test might ultimately mean less Pt is needed in a fuel cell; this again translates into cost savings. Finally, enhanced long-term stability is a key driver within the fuel cell community as improvements in this area must be realized before fuel cells find their way into the marketplace; these Pt/C materials hold great promise of enhanced stability over time. An external laser desorption ion source was successfully installed on the existing Fourier transform ion-cyclotron resonance (FT-ICR) mass spectrometer. However, operation of this laser ablation source has only generated metal atom ions, no clusters have been found to date. It is believed that this is due to the design of the pulsed-nozzle/laser vaporization chamber. The final experimental configuration and design of the two source housings are described.

  8. Combustion Dynamics in Multi-Nozzle Combustors Operating on High-Hydrogen Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Santavicca, Dom; Lieuwen, Tim

    2013-09-30

    Actual gas turbine combustors for power generation applications employ multi-nozzle combustor configurations. Researchers at Penn State and Georgia Tech have extended previous work on the flame response in single-nozzle combustors to the more realistic case of multi-nozzle combustors. Research at Georgia Tech has shown that asymmetry of both the flow field and the acoustic forcing can have a significant effect on flame response and that such behavior is important in multi-flame configurations. As a result, the structure of the flame and its response to forcing is three-dimensional. Research at Penn State has led to the development of a three-dimensional chemiluminescence flame imaging technique that can be used to characterize the unforced (steady) and forced (unsteady) flame structure of multi-nozzle combustors. Important aspects of the flame response in multi-nozzle combustors which are being studied include flame-flame and flame-wall interactions. Research at Penn State using the recently developed three-dimensional flame imaging technique has shown that spatial variations in local flame confinement must be accounted for to accurately predict global flame response in a multi-nozzle can combustor.

  9. Pre: Surgical orthopedic pre-maxillary alignment in bilateral cleft lip and palate patient

    Directory of Open Access Journals (Sweden)

    Vijaya Prasad Kamavaram Ellore

    2012-01-01

    Full Text Available Pre-surgical orthopedic appliances are mainly used to retract and align the protruded and deviated pre-maxilla and to facilitate initial lip repair. This article presents a case report of a five year old male child patient with bilateral cleft lip and palate in whom a special custom made pre-surgical orthopedic appliance was delivered. Use of a special custom made presurgical orthopedic appliance for repositioning pre-maxilla in bilateral cleft lip and palate patient is discussed in this article.

  10. Pre-crastination in the pigeon.

    Science.gov (United States)

    Wasserman, Edward A; Brzykcy, Stephen J

    2015-08-01

    Procrastination is the tendency to delay initiating or completing tasks. Rosenbaum et al. (Psychological Science, May 8, 2014) recently documented the opposite of procrastination: pre-crastination, the tendency to begin or to finish tasks as soon as possible. We devised a simple two-alternative forced-choice task, in which pigeons could choose to switch response location either sooner or later in a sequence of actions eventuating in food reward. Even though there was no economic advantage for doing so, pigeons chose to switch response location sooner rather than later in the sequence, showing pre-crastination to be quite general. Pre-crastination thus joins other anticipatory learning phenomena in challenging rational or optimal accounts of behavioral adaptation.

  11. 40 CFR 1065.520 - Pre-test verification procedures and pre-test data collection.

    Science.gov (United States)

    2010-07-01

    ... corrective action does not resolve the deficiency, you may request to use the contaminated system as an... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Pre-test verification procedures and pre-test data collection. 1065.520 Section 1065.520 Protection of Environment ENVIRONMENTAL PROTECTION...

  12. Prevalence and risk factors of pre-hypertension in Congolese pre ...

    African Journals Online (AJOL)

    Prevalence and risk factors of pre-hypertension in Congolese pre and post menopausal women. M.J.S. Muchanga, F.B. Lepira, R Tozin, E.P. Mbelambela, N.R. Ngatu, E.K. Sumaili, J.R. Makulo, N Suganuma ...

  13. Sulphur cement pre-composition and process for preparing such sulphur cement pre-composition

    NARCIS (Netherlands)

    2013-01-01

    The invention provides a process for the preparation of a sulphur cement pre-composition comprising reacting sulphur modifier with polysulphide-containing organosilane to obtain in the presence of sulphur the sulphur cement pre-composition, wherein the organosilane has the general molecular formula:

  14. Pre-hospital critical care by anaesthesiologist-staffed pre-hospital services in Scandinavia

    DEFF Research Database (Denmark)

    Krüger, A J; Lossius, H M; Mikkelsen, S

    2013-01-01

    All Scandinavian countries provide anaesthesiologist-staffed pre-hospital services. Little is known of the incidence of critical illness or injury attended by these services. We aimed to investigate anaesthesiologist-staffed pre-hospital services in Scandinavia with special emphasis on incidence...

  15. Pre-operative fasting guidelines: an update

    DEFF Research Database (Denmark)

    Søreide, E; Eriksson, L I; Hirlekar, G

    2005-01-01

    Liberal pre-operative fasting routines have been implemented in most countries. In general, clear fluids are allowed up to 2 h before anaesthesia, and light meals up to 6 h. The same recommendations apply for children and pregnant women not in labour. In children......Liberal pre-operative fasting routines have been implemented in most countries. In general, clear fluids are allowed up to 2 h before anaesthesia, and light meals up to 6 h. The same recommendations apply for children and pregnant women not in labour. In children...

  16. Pre-aggregation for Probability Distributions

    DEFF Research Database (Denmark)

    Timko, Igor; Dyreson, Curtis E.; Pedersen, Torben Bach

    Motivated by the increasing need to analyze complex uncertain multidimensional data (e.g., in order to optimize and personalize location-based services), this paper proposes novel types of {\\em probabilistic} OLAP queries that operate on aggregate values that are probability distributions...... and the techniques to process these queries. The paper also presents the methods for computing the probability distributions, which enables pre-aggregation, and for using the pre-aggregated distributions for further aggregation. In order to achieve good time and space efficiency, the methods perform approximate...... multidimensional data analysis that is considered in this paper (i.e., approximate processing of probabilistic OLAP queries over probability distributions)....

  17. Social games with pre-school children

    OpenAIRE

    Tomažin, Maja

    2013-01-01

    The aim of the thesis Social games with pre-school children is to present social games as one of the work methods for relational learning. The theoretical part defines the social development of pre-school children and focuses on social skills that begin to emerge in the preschool period and of course social games. The purpose of social games is active learning, meaning they provide concrete situations, through which children actively learn as well as use social skills and express their views ...

  18. Pre-calculus workbook for dummies

    CERN Document Server

    Kuang, Yang

    2011-01-01

    Get the confidence and math skills you need to get started with calculus Are you preparing for calculus? This hands-on workbook helps you master basic pre-calculus concepts and practice the types of problems you'll encounter in the course. You'll get hundreds of valuable exercises, problem-solving shortcuts, plenty of workspace, and step-by-step solutions to every problem. You'll also memorize the most frequently used equations, see how to avoid common mistakes, understand tricky trig proofs, and much more. Pre-Calculus Workbook For Dummies is the perfect tool for anyone who wa

  19. What Guides PreK Programs?

    Science.gov (United States)

    Graue, Elizabeth; Ryan, Sharon; Wilinski, Bethany; Northey, Kaitlin; Nocera, Amato

    2018-01-01

    Background/Context: Early childhood education joined the standards movement in 2002 with the Good Start, Grow Smart initiative (Brown, 2007), with advocates arguing that standards were a tool for creating more continuity and coherence in PreK systems (Bowman, 2006; Kagan 2012). Critics posed concerns about a perceived poor fit between…

  20. Pre-Class Planning for Individualized Accounting

    Science.gov (United States)

    Clayton, Dean; Brooke, Joyce Ann

    1974-01-01

    Pre-class planning of individualized accounting is involved with goals, objectives, and activities developed and selected by the teacher in providing compatibility between accounting content and teaching strategy. A systematic arrangement of activities should be developed so that students can understand and apply accounting principles at their own…

  1. Pulmonary venous abnormalities encountered on pre ...

    African Journals Online (AJOL)

    Multidetector computed tomography (MDCT) elegantly renders pulmonary venous anatomy. With increasing numbers of radiofrequency ablation procedures being performed, there is now a greater emphasis on pre-procedure imaging to delineate this anatomy. Pulmonary venous mapping studies can be performed with or ...

  2. Pre-wired systems prove their worth.

    Science.gov (United States)

    2012-03-01

    The 'new generation' of modular wiring systems from Apex Wiring Solutions have been specified for two of the world's foremost teaching hospitals - the Royal London and St Bartholomew's Hospital, as part of a pounds sterling 1 billion redevelopment project, to cut electrical installation times, reduce on-site waste, and provide a pre-wired, factory-tested, power and lighting system. HEJ reports.

  3. Pre-equilibrium complex particle emission

    International Nuclear Information System (INIS)

    Bĕták, E.

    2002-01-01

    Semi-classical (phenomenological) pre-equilibrium emission of clusters of nucleons (complex particles) such as deuterons, tritons, helions and α particles from reactions induced by light projectiles (nucleons to α’s) is addressed. The main attention is given to the hard components in the emission energetic spectra, which play an increasing role at incident energies above 20 MeV, and are currently attributed to a presence of some kind of pre-equilibrium processes. In addition, the mechanisms of cluster reactions show special features such as the competition between pickup and knockout processes and the contributions of several successive steps in the reaction. The main frame used here to illustrate the processes and interplays of the competing mechanisms of pre-equilibrium cluster formation and emission, namely the coalescence, pick-up and knock-out, is the pre-equilibrium exciton model. It obviously contains the process of clusterization itself as its organic part. The most important case of complex particles with the largest amount of experimental data is that of alpha emission, which therefore naturally attracts most of the attention and where the widest range of possible mechanisms is available on the market. The loosely bound ejectiles, on the other side, are usually not able to demonstrate all features of the whole spectrum of contributing mechanisms, but they are nevertheless an important link between the nucleon emission and the cluster one.

  4. Hierarchical pre-segmentation without prior knowledge

    NARCIS (Netherlands)

    Kuijper, A.; Florack, L.M.J.

    2001-01-01

    A new method to pre-segment images by means of a hierarchical description is proposed. This description is obtained from an investigation of the deep structure of a scale space image – the input image and the Gaussian filtered ones simultaneously. We concentrate on scale space critical points –

  5. Pre-Service Teachers and Classroom Authority

    Science.gov (United States)

    Pellegrino, Anthony M.

    2010-01-01

    This study examined the classroom practices of five pre-service teachers from three secondary schools in a large southeastern state. Through classroom observations, survey responses, reviews of refection logs, and focus-group interview responses, we centered on the issue of developing classroom authority as a means to effective classroom…

  6. Het pre-insolventieakkoord : grondslagen en raamwerk

    NARCIS (Netherlands)

    Tollenaar, Nicolaes

    2016-01-01

    Background and topicality Legislation is currently being prepared, at both the European and the national levels, to introduce proceedings that aim to rescue ailing businesses before formal insolvency proceedings are begun. Such proceedings are commonly referred to as “pre-insolvency” proceedings.

  7. Dissection in Pre-college Education

    OpenAIRE

    Buyukmihci, NC

    2017-01-01

    This paper discusses the educational and ethical issues surrounding dissection of non-human animals in pre-college education. It argues that this exercise has no benefits to students that could possibly be outweighed by the death of healthy animals killed for this purpose.

  8. Inhomogeneous Pre-Big Bang String Cosmology

    OpenAIRE

    Veneziano, Gabriele

    1997-01-01

    An inhomogeneous version of pre--Big Bang cosmology emerges, within string theory, from quite generic initial conditions, provided they lie deeply inside the weak-coupling, low-curvature regime. Large-scale homogeneity, flatness, and isotropy appear naturally as late-time outcomes of such an evolution.

  9. Medication or Lifestyle for Pre-Diabetes

    Science.gov (United States)

    ... Disease Venous Thromboembolism Aortic Aneurysm More Medication or Lifestyle Changes for Pre-diabetes Updated:Aug 30,2016 What’s best? Medication or ... doesn’t “fix” things, or make a healthy lifestyle less important. Some people with diabetes will always need some help from medications, but ...

  10. User manual Dieka PreProcessor

    NARCIS (Netherlands)

    Valkering, Kasper

    2000-01-01

    This is the user manual belonging to the Dieka-PreProcessor. This application was written by Wenhua Cao and revised and expanded by Kasper Valkering. The aim of this preproccesor is to be able to draw and mesh extrusion dies in ProEngineer, and do the FE-calculation in Dieka. The preprocessor makes

  11. The 1989 ENDF pre-processing codes

    International Nuclear Information System (INIS)

    Cullen, D.E.; McLaughlin, P.K.

    1989-12-01

    This document summarizes the 1989 version of the ENDF pre-processing codes which are required for processing evaluated nuclear data coded in the format ENDF-4, ENDF-5, or ENDF-6. The codes are available from the IAEA Nuclear Data Section, free of charge upon request. (author)

  12. Advanced CANDU reactor pre-licensing progress

    International Nuclear Information System (INIS)

    Popov, N.K.; West, J.; Snell, V.G.; Ion, R.; Archinoff, G.; Xu, C.

    2005-01-01

    The Advanced CANDU Reactor (ACR) is an evolutionary advancement of the current CANDU 6 reactor, aimed at producing electrical power for a capital cost and at a unit-energy cost significantly less than that of the current reactor designs. The Canadian Nuclear Safety Commission (CNSC) staff are currently reviewing the ACR design to determine whether, in their opinion, there are any fundamental barriers that would prevent the licensing of the design in Canada. This CNSC licensability review will not constitute a licence, but is expected to reduce regulatory risk. The CNSC pre-licensing review started in September 2003, and was focused on identifying topics and issues for ACR-700 that will require a more detailed review. CNSC staff reviewed about 120 reports, and issued to AECL 65 packages of questions and comments. Currently CNSC staff is reviewing AECL responses to all packages of comments. AECL has recently refocused the design efforts to the ACR-1000, which is a larger version of the ACR design. During the remainder of the pre-licensing review, the CNSC review will be focused on the ACR-1000. AECL Technologies Inc. (AECLT), a wholly-owned US subsidiary of AECL, is engaged in a pre-application process for the ACR-700 with the US Nuclear Regulatory Commission (USNRC) to identify and resolve major issues prior to entering a formal process to obtain standard design certification. To date, the USNRC has produced a Pre-Application Safety Assessment Report (PASAR), which contains their reviews of key focus topics. During the remainder of the pre-application phase, AECLT will address the issues identified in the PASAR. Pursuant to the bilateral agreement between AECL and the Chinese nuclear regulator, the National Nuclear Safety Administration (NNSA) and its Nuclear Safety Center (NSC), NNSA/NSC are reviewing the ACR in seven focus areas. The review started in September 2004, and will take three years. The main objective of the review is to determine how the ACR complies

  13. Pre-anaesthetic screening of geriatric dogs

    Directory of Open Access Journals (Sweden)

    K.E. Joubert

    2007-05-01

    Full Text Available Pre-anaesthetic screening has been advocated as a valuable tool for improving anaesthetic safety and determining anaesthetic risk. This study was done determine whether pre-anaesthetic screening result in cancellation of anaesthesia and the diagnosis of new clinical conditions in geriatric dogs. One hundred and one dogs older than 7 years of age provided informed owner consent were included in the study. Each dog was weighed, and its temperature, pulse and respiration recorded. An abdominal palpation, examination of the mouth, including capillary refill time and mucous membranes, auscultation, body condition and habitus was performed and assessed. A cephalic catheter was placed and blood drawn for pre-anaesthetic testing. A micro-haematocrit tube was filled and the packed cell volume determined. The blood placed was in a test tube, centrifuged and then analysed on an in-house blood analyser. Alkaline phosphatase, alanine transferase, urea, creatinine, glucose and total protein were determined. A urine sample was then obtained by cystocentesis, catheterisation or free-flow for analysis. The urine specific gravity was determined with a refractometer. A small quantity of urine was then placed on a dip stick. Any new diagnoses made during the pre-anaesthetic screening were recorded. The average age of the dogs was 10.99+2.44 years and the weight was 19.64+15.78 kg. There were 13 dogs with pre-existing medical conditions. A total of 30 new diagnoses were made on the basis of the pre-anaesthetic screening. The most common conditions were neoplasia, chronic kidney disease and Cushing's disease. Of the 30 patients with a new diagnosis, 13 did not undergo anaesthesia as result of the new diagnosis. From this study it can be concluded that screening of geriatric patients is important and that sub-clinical disease could be present in nearly 30 % of these patients. The value of screening before anaesthesia is perhaps more questionable in terms of

  14. Pre-heating mitigates composite degradation.

    Science.gov (United States)

    Silva, Jessika Calixto da; Rogério Vieira, Reges; Rege, Inara Carneiro Costa; Cruz, Carlos Alberto dos Santos; Vaz, Luís Geraldo; Estrela, Carlos; Castro, Fabrício Luscino Alves de

    2015-01-01

    Dental composites cured at high temperatures show improved properties and higher degrees of conversion; however, there is no information available about the effect of pre-heating on material degradation. Objectives This study evaluated the effect of pre-heating on the degradation of composites, based on the analysis of radiopacity and silver penetration using scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS). Material and Methods Thirty specimens were fabricated using a metallic matrix (2x8 mm) and the composites Durafill VS (Heraeus Kulzer), Z-250 (3M/ESPE), and Z-350 (3M/ESPE), cured at 25°C (no pre-heating) or 60°C (pre-heating). Specimens were stored sequentially in the following solutions: 1) water for 7 days (60°C), plus 0.1 N sodium hydroxide (NaOH) for 14 days (60°C); 2) 50% silver nitrate (AgNO3) for 10 days (60°C). Specimens were radiographed at baseline and after each storage time, and the images were evaluated in gray scale. After the storage protocol, samples were analyzed using SEM/EDS to check the depth of silver penetration. Radiopacity and silver penetration data were analyzed using ANOVA and Tukey's tests (α=5%). Results Radiopacity levels were as follows: Durafill VSZ-350>Z-250 (pheated specimens presented higher radiopacity values than non-pre-heated specimens (pheated specimens (pheating at 60°C mitigated the degradation of composites based on analysis of radiopacity and silver penetration depth.

  15. Aristotelian pre-Socratics, A glance at Aristotle's Narrative from pre-Socratics

    OpenAIRE

    Mehdi Qavam Safari; M.B Ghomi

    2015-01-01

    In this article, it's tried to study Aristotle's narrative of  pre-Socratics on the base of Aristotle's texts and mainly using  metaphysics, physics, genesis and decadence books. It is also tried to show how Aristotle has interpreted all the pre-Socratics in one way and on the base of his own philosophy framework. He interprets pre-Socratic Arche as an element that means comprehensive matter which is nothing itself, but everything is combination of it and even considers that as substance and ...

  16. Nutritional practices in full-day-care pre-schools.

    LENUS (Irish Health Repository)

    Jennings, A

    2011-06-01

    Full-day-care pre-schools contribute significantly to the nutritional intake and acquisition of dietary habits of the pre-school child. The present study investigated nutritional practices in full-day-care pre-schools in Dublin, Ireland, aiming to determine the nutritional support that pre-school managers deem necessary, thereby facilitating the amelioration of existing pre-school nutritional training and practices.

  17. Prevalence and risk factors of pre-hypertension in Congolese pre ...

    African Journals Online (AJOL)

    viduals with pre-hypertension are at high risk of develop- ing clinical hypertension .... blood pressure (BP) was measured on the left arm from each subject with the ... In contrast, no statistically significant differences were found between the ...

  18. Pre-1989 epidemiological surveys of low-level dose pre-conception irradiation

    International Nuclear Information System (INIS)

    Rose, K.S.B.

    1990-01-01

    Information from 59 pre-1989 epidemiological surveys concerning pre-conception irradiation at doses less than 0.1 Gy has been collated to determine whether any consistent patterns of health effects emerge. The surveys are considered in three groups: childhood malignancies, Down's syndrome and indicators of reproductive damage. Although a pattern is observed for Down's syndrome, no reliable associations are apparent for childhood malignancies (where all surveys pre-date the Gardner survey at Sellafield) or indications of reproductive damage. The twelve surveys of Down's syndrome in relation to maternal pre-conception irradiation received for medical reasons show a pattern consistent with a doubling dose of about 20 mGy. This doubling dose value is, however, not based on individual measurements of ovarian dose and is inconsistent with results from high-level dose surveys. There is no association between paternal irradiation and Down's syndrome. (author)

  19. Extension of the pre-retirement programmes

    CERN Multimedia

    2015-01-01

    Following a recommendation by the Standing Concertation Commitee at its meeting on 9 November 2015 and approval by the Director-General, please note that:   the Progressive Retirement Programme has been extended by one year, from 1 April 2016 until 31 March 2017;   the Scheme of Part-Time Work as a Pre-retirement Measure has also been extended by one year, from 1 January 2016 until 31 December 2016. Further information is available from the following sites: - https://admin-eguide.web.cern.ch/en/procedure/progressive-retirement-programme-prp - https://admin-eguide.web.cern.ch/en/procedure/part-time-work-pre-retirement-measure-ptp Human Resources Department Tel.: 79257 / 73903

  20. Pre-Columbian Earthworks in Coastal Amazonia

    Directory of Open Access Journals (Sweden)

    Stéphen Rostain

    2010-03-01

    Full Text Available As in other parts of Amazonia, pre-Columbian Indians have profoundly modified the coast of the Guianas. Between 650 and 1650 AD, Arauquinoid people occupied a territory that was approximately 600 km long and used the raised field technique intensively before the European conquest. They erected thousands of raised fields of various shapes, dug canals, ditches, and pathways, and built artificial mounds to establish their villages. All these earthworks changed forever the face of the coastal flooded savannas and their ecology. Such labor was probably organized under the leadership of a central authority: it seems that Arauquinoid societies were organized in a chiefdom system. Statistical calculations, based on the known surface area of raised fields and on their estimated productivity, suggest a population density of 50 to 100 inhabitants per km2. Pre-Columbian inhabitants of the Guianas coast carefully organized, managed and “anthropisized” their territory following a specific pattern.

  1. INCLUSIVE CULTURE IN PRE-SCHOOL INSTITUTIONS

    Directory of Open Access Journals (Sweden)

    Irena NOVACHEVSKA

    2011-04-01

    Full Text Available Inclusive education is a rational concept that refers to the overall and long-term transformation of institutional systems in society, especially in education. Along with the transformation, a number of important and unresolved issues still appear in both theory and practice, as the duty of pre-school institutions and schools is to educate every student in the mainstream education system. One of the most important aspects of inclusion is the inclusive culture. Regardless of the good inclusive policy and practice, one cannot talk about successful inclusion without a properly developed inclusive institutional culture.This paper is a contribution to the research considering the development of inclusive culture in three preschool institutions. It is based on the thinking and attitudes of the pre­school staff toward the necessity of developing and nurturing an inclusive culture. Successful inclusion of pupils with special needs in the mainstream school system cannot be conceived without an inclusive culture.

  2. Research on pre-staining gel electrophoresis

    International Nuclear Information System (INIS)

    Zhong Ruibo; Liu Yushuang; Zhang Ping; Liu Jingran; Zhao Guofen; Zhang Feng

    2014-01-01

    Background: Gel electrophoresis is a powerful biochemical separation technique. Most biological molecules are completely transparent in the visible region of light, so it is necessary to use staining to show the results after gel electrophoresis, and the general steps of conventional staining methods are time-consuming. Purpose: We try to develop a novel approach to simplify the gel electrophoresis: Pre-Staining Gel Electrophoresis (PSGE), which can make the gel electrophoresis results monitored in real time. Methods: Pre-stain the protein samples with Coomassie Brilliant Blue (CBB) for 30 min before loading the sample into the gel well. Results and Conclusion: PSGE can be successfully used to analyze the binding efficiency of Bovine Serum Albumin (BSA) and amphiphilic polymer via chemical coupling and physical absorption, and the double PSGE also shows a great potential in bio-analytical chemistry. (authors)

  3. An overview of pre-surgical evaluation

    Directory of Open Access Journals (Sweden)

    Kurupath Radhakrishnan

    2014-01-01

    Full Text Available The success of an epilepsy surgery program depends upon the early identification of potential surgical candidates and selecting from them, ideal candidates for surgery, who are destined to have a post-operative seizure-free outcome without any unacceptable neurological deficits. Since epilepsy surgery centers in resource-poor countries will lack the full range of state-of-the-art technologies usually available in resource-rich countries to perform pre-surgical evaluation, cost-effectively utilization of the locally available investigative facilities to select the surgical candidates becomes challenging. In the present era of rapid electronic communications and telemedicine, it has become possible for epilepsy surgery centers to pool their technological and human resources and to partner with centers nationally and internationally in implementing pre-surgical evaluation strategies.

  4. Pre-operative optimisation of lung function

    Directory of Open Access Journals (Sweden)

    Naheed Azhar

    2015-01-01

    Full Text Available The anaesthetic management of patients with pre-existing pulmonary disease is a challenging task. It is associated with increased morbidity in the form of post-operative pulmonary complications. Pre-operative optimisation of lung function helps in reducing these complications. Patients are advised to stop smoking for a period of 4–6 weeks. This reduces airway reactivity, improves mucociliary function and decreases carboxy-haemoglobin. The widely used incentive spirometry may be useful only when combined with other respiratory muscle exercises. Volume-based inspiratory devices have the best results. Pharmacotherapy of asthma and chronic obstructive pulmonary disease must be optimised before considering the patient for elective surgery. Beta 2 agonists, inhaled corticosteroids and systemic corticosteroids, are the main drugs used for this and several drugs play an adjunctive role in medical therapy. A graded approach has been suggested to manage these patients for elective surgery with an aim to achieve optimal pulmonary function.

  5. The 1996 ENDF pre-processing codes

    International Nuclear Information System (INIS)

    Cullen, D.E.

    1996-01-01

    The codes are named 'the Pre-processing' codes, because they are designed to pre-process ENDF/B data, for later, further processing for use in applications. This is a modular set of computer codes, each of which reads and writes evaluated nuclear data in the ENDF/B format. Each code performs one or more independent operations on the data, as described below. These codes are designed to be computer independent, and are presently operational on every type of computer from large mainframe computer to small personal computers, such as IBM-PC and Power MAC. The codes are available from the IAEA Nuclear Data Section, free of charge upon request. (author)

  6. Aristotelian pre-Socratics, A glance at Aristotle's Narrative from pre-Socratics

    Directory of Open Access Journals (Sweden)

    Mehdi Qavam Safari

    2015-02-01

    Full Text Available In this article, it's tried to study Aristotle's narrative of  pre-Socratics on the base of Aristotle's texts and mainly using  metaphysics, physics, genesis and decadence books. It is also tried to show how Aristotle has interpreted all the pre-Socratics in one way and on the base of his own philosophy framework. He interprets pre-Socratic Arche as an element that means comprehensive matter which is nothing itself, but everything is combination of it and even considers that as substance and the other things as accident. He interprets the distinction of Arche and other things on the basis of this contrast in his philosophy. Aristotle, also analyzes pre-Socratics' viewpoint to change on the base of his distinction among change, genesis and corruption. All these cases show that Aristotle has interpreted the pre-Socratics on the basis of his thought, as Aristotelians. On this basis, since Aristotle's thoughts are the first and the most important sources of pre-Socratic philosophy, Aristotle's role should be considered in studies.

  7. Pre- and postoperative MR imaging of craniopharyngiomas

    Energy Technology Data Exchange (ETDEWEB)

    Hald, J.K. [Rijkshospitalet, Oslo (Norway). Dept. of Radiology; Eldevik, O.P. [Rijkshospitalet, Oslo (Norway). Dept. of Neurosurgery; Quint, D.J. [Rijkshospitalet, Oslo (Norway). Dept. of Neurosurgery; Chandler, W.F. [Univ. of Michigan Hospital, Ann Arbor, MI (United States). Dept. of Radiology; Kollevold, T. [Univ. of Michigan Hospital, Ann Arbor, MI (United States). Dept. of Neurosurgery

    1996-09-01

    Purpose: To compare the pre- and postoperative MR appearance of craniopharyngiomas with respect to lesion size, tumour morphology and identification of surrounding normal structures. Material and Methods: MR images obtained prior to and following craniopharyngioma resection were evaluated retrospectively in 10 patients. Tumour signal charcteristics, size and extension with particular reference to the optic chiasm, the pituitary gland, the pituitary stalk and the third ventricle were evaluated. Results: Following surgery, tumour volume was reduced in all patients. In 6 patients there was further tumour volume reduction between the first and second postoperative images. Two of these patients received radiation therapy between the 2 postoperative studies, while 4 had no adjuvant treatment to the surgical intervention. There was improved visualization of the optic chiasm, in 3, the pituitary stalk in one, and the third ventricle in 9 of the 10 patients. The pituitary gland was identified preoperatively only in one patient, postoperatively only in another, pre- and postoperatively in 5, and neither pre- nor postoperatively in 3 patients. In 3 patients MR imaging 0-7 days postoperatively identified tumour remnants not seen at the end of the surgical procedure. The signal intensities of solid and cystic tumour components were stable from pre- to the first postoperative MR images. Optic tract increased signal prior to surgery was gone 28 days postoperatively in one patient, but persisted on the left side for 197 days after surgery in another. Conclusion: Postoperative MR imaging of craniopharyngiomas demonstrated tumour volume reduction and tumour remnants not seen at surgery. Early postoperative MR imaging of craniopharyngiomas may overestimate the size of residual tumour. Improved visualization of peritumoral structures may be achieved. (orig.).

  8. [Apical resorption in pre-surgical orthodontics].

    Science.gov (United States)

    Piasente, M; Merlini, C; Amelotti, C; Antonioli, M; Roghi, M

    1991-07-15

    Apical root resorption is a frequent phenomenon observed in pre-surgical orthodontic; the reason is double: we deal with adult patients and we often move the teeth in the opposite direction compared to the position obtained in previous inefficacious orthodontic treatments. Notwithstanding the amount of apical root resorption we couldn't record an hyper-mobility of the teeth and a long term evaluation of occlusal stability didn't show any significant change.

  9. International express student's book : pre-intermediate

    CERN Document Server

    Taylor, Liz

    1996-01-01

    The New Edition of International Express Pre-Intermediate retains all the keys features of this popular and successel four-level course. It combines engaging, up-to-date topics with a time-efficient and student-centred approach to language work, and clearly focused activities that reflect learner's real communicative needs - the ideal course for professional adults who use English for work, travel, and socializing.

  10. Pre-surgical register of tobacco consumption.

    Science.gov (United States)

    Gavilán, Eva; Moreno, Montse; Pérez, Àngels; Castellano, Yolanda; Fernández, Esteve; Martínez, Cristina

    2018-03-24

    Smoking cessation before surgery decreases the risk of complications. The aim of this study was to analyse the smoking register, associated variables and a short talk given to smokers in pre-surgical visits. Cross-sectional study. The pre-surgical records of 680 patients were assessed. We selected patient sociodemographic variables, surgical intervention characteristics, smoking status and consumption pattern. Logistic regression was used to study the variables association with smoking. A percentage of 97.2 of the pre-surgical records include information on tobacco consumption. Overall 20% of surgical patients are smokers. The probability of smoking is higher among men (adjusted odds ratio [aOR] 2.6, 95% confidence interval [CI] 1.7-4.0) and≤60 years (aOR 5.4, 95% CI 3.2-9.1). None of the records had information regarding a short talk given to patients to give up smoking. Smoking consumption was prevalent, but the characterisation of a smoker's profile and short talk given to patient before surgery was practically nonexistent. Ensuring that patients who smokes receives a short talk to give up smoking before surgery is necessary. Copyright © 2018 Elsevier España, S.L.U. All rights reserved.

  11. Spontaneous bending of pre-stretched bilayers.

    Science.gov (United States)

    DeSimone, Antonio

    2018-01-01

    We discuss spontaneously bent configurations of pre-stretched bilayer sheets that can be obtained by tuning the pre-stretches in the two layers. The two-dimensional nonlinear plate model we use for this purpose is an adaptation of the one recently obtained for thin sheets of nematic elastomers, by means of a rigorous dimensional reduction argument based on the theory of Gamma-convergence (Agostiniani and DeSimone in Meccanica. doi:10.1007/s11012-017-0630-4, 2017, Math Mech Solids. doi:10.1177/1081286517699991, arXiv:1509.07003, 2017). We argue that pre-stretched bilayer sheets provide us with an interesting model system to study shape programming and morphing of surfaces in other, more complex systems, where spontaneous deformations are induced by swelling due to the absorption of a liquid, phase transformations, thermal or electro-magnetic stimuli. These include bio-mimetic structures inspired by biological systems from both the plant and the animal kingdoms.

  12. Rotational inhomogeneities from pre-big bang?

    International Nuclear Information System (INIS)

    Giovannini, Massimo

    2005-01-01

    The evolution of the rotational inhomogeneities is investigated in the specific framework of four-dimensional pre-big bang models. While minimal (dilaton-driven) scenarios do not lead to rotational fluctuations, in the case of non-minimal (string-driven) models, fluid sources are present in the pre-big bang phase. The rotational modes of the geometry, coupled to the divergenceless part of the velocity field, can then be amplified depending upon the value of the barotropic index of the perfect fluids. In the light of a possible production of rotational inhomogeneities, solutions describing the coupled evolution of the dilaton field and of the fluid sources are scrutinized in both the string and Einstein frames. In semi-realistic scenarios, where the curvature divergences are regularized by means of a non-local dilaton potential, the rotational inhomogeneities are amplified during the pre-big bang phase but they decay later on. Similar analyses can also be performed when a contraction occurs directly in the string frame metric

  13. Rotational inhomogeneities from pre-big bang?

    Energy Technology Data Exchange (ETDEWEB)

    Giovannini, Massimo [Department of Physics, Theory Division, CERN, 1211 Geneva 23 (Switzerland)

    2005-01-21

    The evolution of the rotational inhomogeneities is investigated in the specific framework of four-dimensional pre-big bang models. While minimal (dilaton-driven) scenarios do not lead to rotational fluctuations, in the case of non-minimal (string-driven) models, fluid sources are present in the pre-big bang phase. The rotational modes of the geometry, coupled to the divergenceless part of the velocity field, can then be amplified depending upon the value of the barotropic index of the perfect fluids. In the light of a possible production of rotational inhomogeneities, solutions describing the coupled evolution of the dilaton field and of the fluid sources are scrutinized in both the string and Einstein frames. In semi-realistic scenarios, where the curvature divergences are regularized by means of a non-local dilaton potential, the rotational inhomogeneities are amplified during the pre-big bang phase but they decay later on. Similar analyses can also be performed when a contraction occurs directly in the string frame metric.

  14. Pre-test analysis results of a PWR steel lined pre-stressed concrete containment model

    International Nuclear Information System (INIS)

    Basha, S.M.; Ghosh, Barnali; Patnaik, R.; Ramanujam, S.; Singh, R.K.; Kushwaha, H.S.; Venkat Raj, V.

    2000-02-01

    Pre-stressed concrete nuclear containment serves as the ultimate barrier against the release of radioactivity to the environment. This ultimate barrier must be checked for its ultimate load carrying capacity. BARC participated in a Round Robin analysis activity which is co-sponsored by Sandia National Laboratory, USA and Nuclear Power Engineering Corporation Japan for the pre-test prediction of a 1:4 size Pre-stressed Concrete Containment Vessel. In house finite element code ULCA was used to make the test predictions of displacements and strains at the standard output locations. The present report focuses on the important landmarks of the pre-test results, in sequential terms of first crack appearance, loss of pre-stress, first through thickness crack, rebar and liner yielding and finally liner tearing at the ultimate load. Global and local failure modes of the containment have been obtained from the analysis. Finally sensitivity of the numerical results with respect to different types of liners and different constitutive models in terms of bond strength between concrete and steel and tension-stiffening parameters are examined. The report highlights the important features which could be observed during the test and guidelines are given for improving the prediction in the post test computation after the test data is available. (author)

  15. Elementary Pre-Service Teacher Perceptions of the Greenhouse Effect.

    Science.gov (United States)

    Groves, Fred H.; Pugh, Ava F.

    1999-01-01

    Expands on earlier work to examine pre-service teachers' views on environmental issues, especially global warming and the related term "greenhouse effect." Suggests that pre-service elementary teachers hold many misconceptions about environmental issues. (DDR)

  16. Pre-big bang cosmology and quantum fluctuations

    International Nuclear Information System (INIS)

    Ghosh, A.; Pollifrone, G.; Veneziano, G.

    2000-01-01

    The quantum fluctuations of a homogeneous, isotropic, open pre-big bang model are discussed. By solving exactly the equations for tensor and scalar perturbations we find that particle production is negligible during the perturbative Pre-Big Bang phase

  17. 31 CFR 544.702 - Pre-Penalty Notice; settlement.

    Science.gov (United States)

    2010-07-01

    ... set forth in this paragraph. The failure to submit a response within the applicable time period set... envelope in which the Pre-Penalty Notice was mailed. If the Pre-Penalty Notice was personally delivered by...

  18. Decentralized Planning for Pre-Conflict and Post-Conflict ...

    African Journals Online (AJOL)

    Decentralized Planning for Pre-Conflict and Post-Conflict Management in the Bawku Municipal ... institutional arrangements for conflict monitoring and evaluation. Such processes are 'sine qua non' to pre-conflict and post-conflict prevention.

  19. Extension of the pre-retirement programmes

    CERN Multimedia

    2014-01-01

    Following a recommendation by the Standing Concertation Committee at its meeting on 27 November 2014 and approval by the Director-General, please note that: the Progressive Retirement Programme has been extended by one year, from 1 April 2015 until 31 March 2016; the Scheme of Part-Time Work as a Pre-retirement Measure has also been extended by one year, from 1 January 2015 until 31 December 2015. Further information is available at the following sites: https://admin-eguide.web.cern.ch/node/447 https://admin-eguide.web.cern.ch/node/484 Human Resources Department Tel. 79257 / 73903

  20. Extension of the pre-retirement programmes

    CERN Multimedia

    2014-01-01

    Following a recommendation by the Standing Concertation Commitee at its meeting on 5 December 2013 and approval by the Director-General, please note that:   the Progressive Retirement Programme has been extended by one year, from 1 April 2014 until 31 March 2015; the Scheme of Part-Time Work as a Pre-retirement Measure has also been extended by one year, from 1 January 2014 until 31 December 2014. Further information is available from the following sites: https://cern.ch/admin-eguide/retraite/proc_prp_fr.asp https://cern.ch/admin-eguide/retraite/proc_pTp_fr.asp Human Resources Department Tel. 79257/ 73903

  1. [Management of pre-analytical nonconformities].

    Science.gov (United States)

    Berkane, Z; Dhondt, J L; Drouillard, I; Flourié, F; Giannoli, J M; Houlbert, C; Surgat, P; Szymanowicz, A

    2010-12-01

    The main nonconformities enumerated to facilitate consensual codification. In each case, an action is defined: refusal to realize the examination with request of a new sample, request of information or correction, results cancellation, nurse or physician information. A traceability of the curative, corrective and preventive actions is needed. Then, methodology and indicators are proposed to assess nonconformity and to follow the quality improvements. The laboratory information system can be used instead of dedicated software. Tools for the follow-up of nonconformities scores are proposed. Finally, we propose an organization and some tools allowing the management and control of the nonconformities occurring during the pre-examination phase.

  2. Extension of the pre-retirement programmes

    CERN Document Server

    Human Resources Department

    2011-01-01

    Following recommendation by the Standing Concertation Committee and approval by the Director-General, please note that: the Progressive Retirement Programme has been extended by one year, from 1 April 2011 until 31 March 2012; and the Part-Time Work as a Pre-retirement Measure has also been extended by one year, from 1 January 2011 until 31 December 2011. Further information is available from the following sites: https://cern.ch/admin-eguide/retraite/proc_prp.asp https://cern.ch/admin-eguide/retraite/proc_pTp.asp Tel. 73903

  3. Extension of the pre-retirement programmes

    CERN Document Server

    2012-01-01

    Following recommendation by the Standing Concertation Committee at its meeting on 2 December 2011 and approval by the Director-General, please note that: the Progressive Retirement Programme has been extended by one year, from 1 April 2012 until 31 March 2013; and the Part-Time Work as a Pre-retirement Measure has also been extended by one year, from 1 January 2012 until 31 December 2012. Further information is available from the following sites: https://cern.ch/admin-eguide/retraite/proc_prp.asp https://cern.ch/admin-eguide/retraite/proc_pTp.asp Tel.  73903 Human Resources Department

  4. Extension of the pre-retirement programmes

    CERN Document Server

    2013-01-01

    Following a recommendation by the Standing Concertation Commitee at its meeting on 4 December 2012 and approval by the Director-General, please note that: the Progressive Retirement Programme has been extended by one year, from 1 April 2013 until 31 March 2014; and the Scheme of Part-Time Work as a Pre-retirement Measure has also been extended by one year, from 1 January 2013 until 31 December 2013.   Further information is available from the following sites: https://cern.ch/admin-eguide/retraite/proc_prp_fr.asp https://cern.ch/admin-eguide/retraite/proc_pTp_fr.asp   Human Resources Department Tel. 73903

  5. Pre-sowing irradiation of vegetable seeds

    Energy Technology Data Exchange (ETDEWEB)

    Stoyanov, S

    1975-01-01

    Results are reported of trials with radiation stimulation of vegetable crops conducted under farm conditions in different regions. They were based on exact tests accomplished at the IGHB. Pre-sowing irradiation of seed increased the greenhouse yield of Extase tomato variety by 15%; it increased the yield of Triumph tomato variety under field conditions as well. The pepper variety Kourtovska Kapiya and eggplant variety Bulgarski 12, both grown from irradiated seed in open field produced 18% and 5.5% higher yields, respectively. Irradiation of vegetable seeds finds a large application in the farm practice.

  6. Pre-calculus workbook for dummies

    CERN Document Server

    Gilman, Michelle Rose; Neal, Karina

    2009-01-01

    Get the confidence and the math skills you need to get started with calculus! Are you preparing for calculus? This easy-to-follow, hands-on workbook helps you master basic pre-calculus concepts and practice the types of problems you'll encounter in your cour sework. You get valuable exercises, problem-solving shortcuts, plenty of workspace, and step-by-step solutions to every problem. You'll also memorize the most frequently used equations, see how to avoid common mistakes, understand tricky trig proofs, and much more. 100s of Problems! Detailed, fully worked-out solutions to problem

  7. Pre-sowing irradiation of vegetable seeds

    International Nuclear Information System (INIS)

    Stoyanov, S.

    1975-01-01

    Results are reported of trials with radiation stimulation of vegetable crops conducted under farm conditions in different regions. They were based on exact tests accomplished at the IGHB. Pre-sowing irradiation of seed increased the greenhouse yield of Extase tomato variety by 15%; it increased the yield of Triumph tomato variety under field conditions as well. The pepper variety Kourtovska Kapiya and eggplant variety Bulgarski 12, both grown from irradiated seed in open field produced 18% and 5.5% higher yields, respectively. Irradiation of vegetable seeds finds a large application in the farm practice. (author)

  8. Pre - big bang inflation requires fine tuning

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Michael S. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Weinberg, Erick J. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)

    1997-10-01

    The pre-big-bang cosmology inspired by superstring theories has been suggested as an alternative to slow-roll inflation. We analyze, in both the Jordan and Einstein frames, the effect of spatial curvature on this scenario and show that too much curvature --- of either sign --- reduces the duration of the inflationary era to such an extent that the flatness and horizon problems are not solved. Hence, a fine-tuning of initial conditions is required to obtain enough inflation to solve the cosmological problems.

  9. Neurosonography of the pre-term neonate

    International Nuclear Information System (INIS)

    Grant, E.G.

    1986-01-01

    This book provides a description of our present understanding of the premature brain as seen through the eyes of the sonogram. Neurosonography of the Pre-Term Neonate ties the pathophysiology, anatomy and the all important clinical follow-up data to the sonogram. The book is divided into five sections: Scanning Techniques and Normal Anatomy, Pathophysiology of Germinal Matrix Related Hemorrhage and Ischemia, Neurosonography - Germinal Matrix Related Hemorrhage - Periventricular Leukomalacia, Incidence and Outcome - Germinal Matrix Related Hemorrhage - Periventricular Leukomalacia and Comparison of Two Modalities: Ultrasound versus Computed Tomography

  10. The Soleil detailed pre-project report

    International Nuclear Information System (INIS)

    1999-01-01

    The aim of the joint CNRS/CEA Soleil project was to develop a facility equipped with several synchrotron radiation sources and their associated experimental devices in order to answer the estimated research needs in this domain for the 20 to 30 forthcoming years. This document is the detailed pre-project. It describes the studies carried out and relative to the infrastructures and buildings, to the accelerators and light sources (storage ring, injector, radiation production), to the program of experiments, to the computer science aspects, and to the administrative and organisational aspects. (J.S.)

  11. Is human placenta proteoglycan remodeling involved in pre-eclampsia?

    OpenAIRE

    Warda, Mohamad; Zhang, Fuming; Radwan, Moustafa; Zhang, Zhenqing; Kim, Nari; Kim, Young Nam; Linhardt, Robert J.; Han, Jin

    2007-01-01

    Impaired placento-fetal communication is a coherent symptom of exaggerated pre-eclampsia. The impact of the cellular expression of different glycosaminoglycans (GAGs) in this event on the placenta in pre-eclampsia is still obscure. This is the first study aimed at discovering the relationship between structural alterations of different sulfated GAGs at the molecular level and the development of pre-eclampsia in inflicted placenta. Sulfated GAGs were isolated and purified from control and pre-...

  12. Pre-operative haematological investigations in paediatric orofacial ...

    African Journals Online (AJOL)

    Pre-operative haematological investigations in paediatric orofacial cleft repair: Any relevance to management outcome? ... Aim and Objectives: To determine the value of routine pre-operative haematologic investigations in children undergoing orofacial cleft repair. Background: Although routine pre-operative laboratory ...

  13. Pre-crash system validation with PRESCAN and VEHIL

    NARCIS (Netherlands)

    Gietelink, O.J.; Verburg, D.J.; Labibes, K.; Oostendorp, A.F.

    2004-01-01

    This paper presents the tools for design and validation of Pre-Crash Systems: the software tool PRE-crash SCenario ANalyzer (PRESCAN) and the VEhicle-Hardware-In-the-Loop (VEHIL) facility. PRESCAN allows to investigate a pre-crash scenario in simulation. This scenario can then be compared with tests

  14. Pre-Diabetes Non-Modifiable Risk Factors

    Science.gov (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Pre-diabetes Non-modifiable Risk Factors Updated:Nov 9,2015 ... This content was last reviewed August 2015. Pre-diabetes • Introduction • About Pre-diabetes • What's the Problem? Intro ...

  15. 22 CFR 226.11 - Pre-award policies.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Pre-award policies. 226.11 Section 226.11 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Pre-award Requirements § 226.11 Pre-award policies. (a) Use of grants and...

  16. Pre-Service Science and Mathematics Teachers' Thoughts about Technology

    Science.gov (United States)

    Aran, Özge Can; Derman, Ipek; Yagci, Esed

    2016-01-01

    This study aims to investigate pre-service teachers' opinions about the technology. In this respect, the opinions of pre-service science and mathematics teachers were taken. The study was carried out at a university, located in the capital of Turkey. The data were collected from 20 pre-service teachers in the department of secondary school science…

  17. Construction environment education development activity for children pre-school

    OpenAIRE

    MA. TRAN THI THUY NGA; MA. PHAM THI YEN

    2015-01-01

    Education motor development contribute to the comprehensive development of pre-school children. Building educational environment for young athletes develop in pre-school is one of many issues of concern in the current stage of pre-school education in Vietnam.

  18. An Investigation of School Violence and Pre-Service Teachers

    Science.gov (United States)

    McCaleb, Karen Nykorchuk; Andersen, Amy; Hueston, Harry

    2008-01-01

    All educators need to be aware of issues regarding school violence. Recent years have shown that violence can happen in a variety of school settings. This study conducted a one-group, pretest-posttest, pre-experimental design to explore pre-service teachers' perceptions regarding school violence. First, pre-service educators were asked to complete…

  19. Pre-Service Teachers' Opinions on Teaching Thinking Skills

    Science.gov (United States)

    Akinoglu, Orhan; Karsantik, Yasemin

    2016-01-01

    The purpose of the present study is to determine pre-service teachers' opinions on teaching thinking skills. 134 senior pre-service pre-school, English and mathematics teachers studying at a state university in Istanbul participated in the study which is designed based on survey model. A questionnaire which was developed by the researchers was…

  20. 7 CFR 58.919 - Pre-heat, pasteurization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Pre-heat, pasteurization. 58.919 Section 58.919... Procedures § 58.919 Pre-heat, pasteurization. When pasteurization is intended or required by either the vat... requirements outlined in § 58.128. Pre-heat temperatures prior to ultra pasteurization will be those that have...

  1. Structural motifs of pre-nucleation clusters.

    Science.gov (United States)

    Zhang, Y; Türkmen, I R; Wassermann, B; Erko, A; Rühl, E

    2013-10-07

    Structural motifs of pre-nucleation clusters prepared in single, optically levitated supersaturated aqueous aerosol microparticles containing CaBr2 as a model system are reported. Cluster formation is identified by means of X-ray absorption in the Br K-edge regime. The salt concentration beyond the saturation point is varied by controlling the humidity in the ambient atmosphere surrounding the 15-30 μm microdroplets. This leads to the formation of metastable supersaturated liquid particles. Distinct spectral shifts in near-edge spectra as a function of salt concentration are observed, in which the energy position of the Br K-edge is red-shifted by up to 7.1 ± 0.4 eV if the dilute solution is compared to the solid. The K-edge positions of supersaturated solutions are found between these limits. The changes in electronic structure are rationalized in terms of the formation of pre-nucleation clusters. This assumption is verified by spectral simulations using first-principle density functional theory and molecular dynamics calculations, in which structural motifs are considered, explaining the experimental results. These consist of solvated CaBr2 moieties, rather than building blocks forming calcium bromide hexahydrates, the crystal system that is formed by drying aqueous CaBr2 solutions.

  2. Neuroimaging in pre-motor Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Thomas R. Barber

    2017-01-01

    Full Text Available The process of neurodegeneration in Parkinson's disease begins long before the onset of clinical motor symptoms, resulting in substantial cell loss by the time a diagnosis can be made. The period between the onset of neurodegeneration and the development of motoric disease would be the ideal time to intervene with disease modifying therapies. This pre-motor phase can last many years, but the lack of a specific clinical phenotype means that objective biomarkers are needed to reliably detect prodromal disease. In recent years, recognition that patients with REM sleep behaviour disorder (RBD are at particularly high risk of future parkinsonism has enabled the development of large prodromal cohorts in which to investigate novel biomarkers, and neuroimaging has generated some of the most promising results to date. Here we review investigations undertaken in RBD and other pre-clinical cohorts, including modalities that are well established in clinical Parkinson's as well as novel imaging methods. Techniques such as high resolution MRI of the substantia nigra and functional imaging of Parkinsonian brain networks have great potential to facilitate early diagnosis. Further longitudinal studies will establish their true value in quantifying prodromal neurodegeneration and predicting future Parkinson's.

  3. Changes in cognitive control in pre-manifest Huntington's disease examined using pre-saccadic EEG potentials - a longitudinal study.

    Science.gov (United States)

    Ness, Vanessa; Bestgen, Anne-Kathrin; Saft, Carsten; Beste, Christian

    2014-01-01

    It is well-known that Huntington's disease (HD) affects saccadic processing. However, saccadic dysfunctions in HD may be seen as a result of dysfunctional processes occurring at the oculomotor level prior to the execution of saccades, i.e., at a pre-saccadic level. Virtually nothing is known about possible changes in pre-saccadic processes in HD. This study examines pre-saccadic processing in pre-manifest HD gene mutation carriers (pre-HDs) by using clinically available EEG measures. Error rates, pre-saccadic EEG potentials and saccade onset EEG potentials were measured in 14 pre-HDs and case-matched controls performing prosaccades and antisaccades in a longitudinal study over a 15-month period. The results show that pre-saccadic potentials were changed in pre-HDs, relative to controls and also revealed changes across the 15-month longitudinal period. In particular, pre-saccadic ERP in pre-HDs were characterized by lower amplitudes and longer latencies, which revealed longitudinal changes. These changes were observed for anti-saccades, but not for pro-saccades. Overt saccadic trajectories (potentials) were not different to those in controls, showing that pre-saccadic processes are sensitive to subtle changes in fronto-striatal networks in pre-HDs. Deficits in pre-saccadic processes prior the execution of an erroneous anti-saccade can be seen as an effect of dysfunctional cognitive control in HD. This may underlie saccadic abnormalities and hence a major phenotype of HD. Pre-saccadic EEG potentials preceding erroneous anti-saccades are sensitive to pre-manifest disease progression in HD.

  4. Who are the young adult Danish pre-drinkers and why do they pre-drink before a night out?

    DEFF Research Database (Denmark)

    Østergaard, Jeanette; Andrade, Stefan Bastholm

    2014-01-01

    cannot explain whether a young person will pre-drink on an event-specific night out, young people's income level and their motives explain the quantities they consume. Lower-earning males who pre-drank to save money consumed larger quantities of alcohol at home, but lower-earning females pre-drank larger...

  5. Risk of early or severe pre-eclampsia related to pre-existing conditions

    DEFF Research Database (Denmark)

    Catov, Janet M; Ness, Roberta B; Kip, Kevin E

    2007-01-01

    BACKGROUND: Preeclampsia (PE), especially severe or early PE, is a leading cause of morbidity and mortality among mothers and infants. We estimated the population attributable fractions of severe or early PE associated with pre-existing conditions among nulliparous and multiparous women. METHODS...

  6. Improving the Leadership Skills of Pre-Service School Librarians through Leadership Pre-Assessment

    Science.gov (United States)

    Smith, Daniella

    2014-01-01

    School librarian guidelines encourage active leadership in schools. Two ways school librarian educators can encourage school librarians to be leaders are to embed the standards into the certification curriculum and to assess the leadership potential of pre-service school librarians in order to adapt the curriculum to their needs. This mixed-method…

  7. evaluation and retiming of a pre evaluation and retiming of a pre

    African Journals Online (AJOL)

    eobe

    1,1,1,1, 2,2,2,2, 3333 DEPARTMENT OF CIVIL ENGINEERING,UNIVERSITY OF BENIN, BENIN ... This study evaluates and retimes a pre-timed traffic signal using the current volume of ... operation of traffic lights provides an effective method.

  8. Pre-School Attendance and Child Development

    DEFF Research Database (Denmark)

    Bauchmüller, Robert; Gørtz, Mette; Rasmussen, Astrid Würtz

    Earlier research suggests that children's development is shaped in their early years of life. This paper examines whether differences in day-care experiences during pre-school age are important for children's cognitive and language development at the age of 15. The analysis is based on class...... performance at the end of elementary schooling. We assess the effects of attended types and qualities of day-care institutions on various child outcomes as measured by school grades in mathematics, science, English and Danish for the whole Danish population as well as outcomes from the 2006 PISA Denmark...... survey and a 2007 PISA Copenhagen survey. We use administrative registries to generate indicators such as child-staff ratios, child-pedagogues ratios, and the share of male staff and of staff with non-Danish origins. Furthermore, we use information on the average levels of educational attainments...

  9. Waves in nonlinear pre-stressed materials

    CERN Document Server

    Schneider, Wilhelm; Saccomandi, G

    2007-01-01

    The papers in this book provide a unique state-of-the-art multidisciplinary overview on the subject of waves in pre-stressed materials through the interaction of several topics, ranging from the mathematical modelling of incremental material response (elastic and inelastic), to the analysis of the governing differential equations and boundary-value problems, and to computational methods for the solution to these problems, with particular reference to industrial, geophysical, and biomechanical applications. A complete view on the title subject is proposed, including: The basic and fundamental theoretical issues (mechanical modelling, exact solutions, asymptotic methods, numerical treatment); A unified introduction to wave propagation (small on large and large on large); A look toward classical (such as geophysics and the mechanics of rubber-like solids) and emergent (such as biomechanics) applications.

  10. Pre-Aggregation with Probability Distributions

    DEFF Research Database (Denmark)

    Timko, Igor; Dyreson, Curtis E.; Pedersen, Torben Bach

    2006-01-01

    Motivated by the increasing need to analyze complex, uncertain multidimensional data this paper proposes probabilistic OLAP queries that are computed using probability distributions rather than atomic values. The paper describes how to create probability distributions from base data, and how...... the distributions can be subsequently used in pre-aggregation. Since the probability distributions can become large, we show how to achieve good time and space efficiency by approximating the distributions. We present the results of several experiments that demonstrate the effectiveness of our methods. The work...... is motivated with a real-world case study, based on our collaboration with a leading Danish vendor of location-based services. This paper is the first to consider the approximate processing of probabilistic OLAP queries over probability distributions....

  11. Warm pre-stressing, preliminary experiments

    International Nuclear Information System (INIS)

    Hedner, G.

    1984-09-01

    The beneficial effect of warm pre-stressing, WPS, on apparent fracture thoughness at low temperature is well established. Tests are usually performed with constant load during the cooling part of the load cycle. In practice load variations may occur during this part. The present paper reports a preliminary study of the influence of superimposed fatigue loads. It is found that if crack propagation occurs during cooling+fatigue loading, then the maximum load during the fatigue load cycle is the preload to be used for WPS consideration. A few tests were preformed to study the effect of preload reversal. Tensile preload was followed by a compressive load and after unloading the specimens were cooled and fractured. It was found that for the high preload level used in the tests, the beneficial effect of the tensile preload could be totally annihilated by the compressive preload. (author)

  12. The 1992 ENDF Pre-processing codes

    International Nuclear Information System (INIS)

    Cullen, D.E.

    1992-01-01

    This document summarizes the 1992 version of the ENDF pre-processing codes which are required for processing evaluated nuclear data coded in the format ENDF-4, ENDF-5, or ENDF-6. Included are the codes CONVERT, MERGER, LINEAR, RECENT, SIGMA1, LEGEND, FIXUP, GROUPIE, DICTION, MIXER, VIRGIN, COMPLOT, EVALPLOT, RELABEL. Some of the functions of these codes are: to calculate cross-sections from resonance parameters; to calculate angular distributions, group average, mixtures of cross-sections, etc; to produce graphical plottings and data comparisons. The codes are designed to operate on virtually any type of computer including PC's. They are available from the IAEA Nuclear Data Section, free of charge upon request, on magnetic tape or a set of HD diskettes. (author)

  13. Do pre-drinkers consume more alcohol than non-pre-drinkers on an event-specific night out?

    DEFF Research Database (Denmark)

    Østergaard, Jeanette; Skov, Peter Rohde

    2014-01-01

    Introduction and Aims Young people drinking heavily before going out to bars and clubs is associated with alcohol-related harm and therefore of great public concern. This study examines whether pre-drinkers consume more alcohol than non-pre-drinkers on an event-specific night out in England...... demographics, socioeconomic status, frequency of intoxication and alcohol unit intake before and during the young people's night out. Results A mixed linear model performed on the panel mobile survey shows that pre-drinkers in England and Denmark consume 9.185 (P ..., respectively, more than the non-pre-drinkers. However, in both countries pre-drinkers consume 3.430 (P alcohol on-premises than the non-pre-drinkers. Discussion and Conclusion Pre-drinking is a widespread phenomenon in England and Denmark, with more than half of young...

  14. Clinical target volume delineation in glioblastomas: pre-operative versus post-operative/pre-radiotherapy MRI

    Science.gov (United States)

    Farace, P; Giri, M G; Meliadò, G; Amelio, D; Widesott, L; Ricciardi, G K; Dall'Oglio, S; Rizzotti, A; Sbarbati, A; Beltramello, A; Maluta, S; Amichetti, M

    2011-01-01

    Objectives Delineation of clinical target volume (CTV) is still controversial in glioblastomas. In order to assess the differences in volume and shape of the radiotherapy target, the use of pre-operative vs post-operative/pre-radiotherapy T1 and T2 weighted MRI was compared. Methods 4 CTVs were delineated in 24 patients pre-operatively and post-operatively using T1 contrast-enhanced (T1PRECTV and T1POSTCTV) and T2 weighted images (T2PRECTV and T2POSTCTV). Pre-operative MRI examinations were performed the day before surgery, whereas post-operative examinations were acquired 1 month after surgery and before chemoradiation. A concordance index (CI) was defined as the ratio between the overlapping and composite volumes. Results The volumes of T1PRECTV and T1POSTCTV were not statistically different (248 ± 88 vs 254 ± 101), although volume differences >100 cm3 were observed in 6 out of 24 patients. A marked increase due to tumour progression was shown in three patients. Three patients showed a decrease because of a reduced mass effect. A significant reduction occurred between pre-operative and post-operative T2 volumes (139 ± 68 vs 78 ± 59). Lack of concordance was observed between T1PRECTV and T1POSTCTV (CI = 0.67 ± 0.09), T2PRECTV and T2POSTCTV (CI = 0.39 ± 0.20) and comparing the portion of the T1PRECTV and T1POSTCTV not covered by that defined on T2PRECTV images (CI = 0.45 ± 0.16 and 0.44 ± 0.17, respectively). Conclusion Using T2 MRI, huge variations can be observed in peritumoural oedema, which are probably due to steroid treatment. Using T1 MRI, brain shifts after surgery and possible progressive enhancing lesions produce substantial differences in CTVs. Our data support the use of post-operative/pre-radiotherapy T1 weighted MRI for planning purposes. PMID:21045069

  15. Energy statistics of pre-revolutionary Russia

    Directory of Open Access Journals (Sweden)

    N. S. Simonov

    2017-01-01

    Full Text Available The article is devoted to the problem of creation and development of the energy statistics of the Russian Empire of the initial stage of electrification and the formation of the energy economy, which is related to: 1 the economic upsurge of the 1890s; 2 the new economic recovery of 1907–1913 and 3 the militarization of industry in 1914–1916. The real technical and economic indicators and complex statistical data of the pre-revolutionary electric power industry were either hushed up or deliberately distorted during the Soviet era. Even in the encyclopaedic literature it was considered that pre-revolutionaryRussia“was on one of the last places in the world” for the production of electricity. The author analyzes statistical surveys (censuses of the manufacturing industry for 1900 and 1908 (the “varzar censuses”, which gave the first material on the state of its energy sector, namely: the composition, quantity and power of primary engines and electric motors. For the first time in historiography, the data of the “energy censuses” of the Ministry of Finance for 1905 and 1913 on the number and capacity of central public power stations and private power stations (block stations of industrial enterprises, organizations and institutions are cited. The data of the census were conducted with the participation of the apparatus of factory and factory inspections in 1906 and in1916 inall provinces of the Russian Empire, with the exception of six provinces of the frontline zone. A lot of work was done to record electricity production / consumption, which was conducted by the Russian electrotechnical community. According to incomplete data published in 1917 by the Secretariat of the Standing Committee of the VII All-Russia Electrotechnical Congress, from 1905 to 1913 (that is, for 8 years the total number of power stations in the Russian Empire increased by 1.7 times, and the amount of electricity produced by them Has grown in 3,8 times. The

  16. Pre-travel advice: an overview.

    Science.gov (United States)

    Sanford, Christopher

    2002-12-01

    The message of the pre-travel provider is necessarily paradoxic. First the provider lists a score of causes of illness and premature demise, and then states, "But it sounds like a great trip and I think you'll have fun." Pre-travel providers need to walk a fine line: they must encourage patients to be cautious but not paranoid, optimistic but realistic. This discussion is complicated further by the fact that risk reduction is not the only consideration; if it were, practitioners would advise patients to remain in the developed world and foray from their homes only to visit health clubs and the fruit-and-vegetable section of grocery stores. A tacit assumption in travel medicine is that some degree of acceptance of heightened risk is tolerated for the benefit of improved quality of life offered by travel abroad. The amount of risk that is reasonable to accept for a given benefit in quality of life yielded by travel cannot be quantified, however. Providers must render judgments on what is "reasonable" and what is not, and this complex decision is based on equal parts medical knowledge and intuition. At one extreme, mountaineers in Nepal have been found to have a 2.4% mortality rate per expedition [83,84]. The travel provider might make the reasonable decision to counsel these travelers to avoid that activity. These travelers most likely will ignore that advice, at which point the provider must endeavor to reduce risk to the extent possible. Other situations in which the provider should advise a change in itinerary or activities include counseling parents who plan to take an infant to high altitude or a pregnant woman who plans to scuba dive. If travelers remain cloistered in their hotel rooms, eating all meals from room service and watching CNN, then it could be suggested that they are overly risk-adverse and might consider foraying out of the hotel, despite the potential associated increased risks to health. Conversely, if travelers find themselves on motorcycles

  17. Are pre-treatment psychological characteristics influenced by pre-surgical orthodontics?

    Science.gov (United States)

    Cunningham, S J; Gilthorpe, M S; Hunt, N P

    2001-12-01

    A number of investigations have looked at psychological changes occurring in association with orthognathic treatment. However, most of these studies have used a pre-surgery questionnaire as the baseline measurement. There is little data relating to the true baseline, i.e. that prior to any active treatment. Until this aspect is investigated, it is not possible to assume that pre-surgery is an acceptable baseline. This questionnaire based study aimed to assess changes in six psychological outcome measures between T1 (prior to any active treatment) and T2 (following pre-surgical orthodontics/prior to surgery). The outcome variables were: state anxiety, trait anxiety, depression, self-esteem, body image, and facial body image. Sixty-two patients (39 females and 23 males) completed both questionnaires. The results showed that intervention, in the form of orthodontic treatment, had a minimal effect on the chosen psychometric outcome variables. There was a significant reduction in satisfaction with body image amongst patients who initially reported mild to moderate dental/facial problems, whilst a moderate increase in satisfaction occurred in those patients reporting severe conditions initially. Also of note were significant increases in state anxiety amongst older patients whilst trait anxiety showed greater increases in females than males.

  18. Development of a pre-ignition submodel for hydrogen engines

    Energy Technology Data Exchange (ETDEWEB)

    Al-Baghdadi, Sadiq [University of Babylon (Iraq). Dept. of Mechanical Engineering

    2005-10-15

    In hydrogen-fuelled spark ignition engine applications, the onset of pre-ignition remains one of the prime limitations that needs to be addressed to avoid its incidence and achieve superior performance. This paper describes a new pre-ignition submodel for engine modelling codes. The effects of changes in key operating variables, such as compression ratio, spark timing, intake pressure, and temperature on pre-ignition limiting equivalence ratios are established both analytically and experimentally. With the established pre-ignition model, it is possible not only to investigate whether pre-ignition is observed with changing operating and design parameters, but also to evaluate those parameters' effects on the maximum possible pre-ignition intensity. (author)

  19. Pre-OSART mission highlights. 1988-1990

    International Nuclear Information System (INIS)

    1994-09-01

    The IAEA Pre-Operational Safety Review Teams (Pre-OSART) programme is part of the Operational Safety Review teams (OSART) programme and provides advice and assistance to Member States for enhancing the operational safety of nuclear power plants. OSART and Pre-OSART reviews are available to all countries with nuclear power plants in operation or approaching operation. Most of these countries have participated in the programme, by hosting one or more OSART or Pre-OSART missions or by making experts available to participate in missions. This document, which summarizes the finding of Pre-OSART reviews, covers the period from January 1988 to December 1990, and it is intended that further such documents will be prepared to cover subsequent Pre-OSART reviews

  20. Pre-tuning of TRISTAN superconducting RF cavities

    International Nuclear Information System (INIS)

    Tajima, Tsuyoshi; Furuya, Takaaki; Suzuki, Toshiji; Iino, Yohsuke.

    1990-01-01

    Pre-tuning of thirty-two TRISTAN superconducting cavities has been done. In this paper are described the pre-tuning system and the results of all the cavities. The average field flatness was 1.4 % after pre-tuning. From our experience, the followings are important, 1) to evacuate the cavity during the process of the pre-tuning to avoid the uncertainty in evacuation, 2) pre-tuning is needed after annealing because it causes changes of the cell length and the field profile and 3) field flatness sometimes changes when expanded and 4) cells should not be expanded more than 1.5 mm after pre-tuning since inelastic deformation occurs. (author)

  1. Pre-slaughter stress and pork quality

    Science.gov (United States)

    Stajković, S.; Teodorović, V.; Baltić, M.; Karabasil, N.

    2017-09-01

    Stress is an inevitable consequence of handling of animals for slaughter. Stress conditions during transport, lairage and at slaughter induce undesirable effects on the end quality of meat such as pale, soft, exudative meat and dark firm dry meat. Hence, it is very important to define appropriate parameters for objective assessment of level of stress. Attempts to define measures of stress have been difficult and no physiological parameter has been successfully used to evaluate stress situations. One physiological change in swine associated with animal handling stress and with pork quality is an increase in blood lactate concentration. Plasma cortisol was thought to be an appropriate indicator of stress, but the concentration was not consistently changed by different stressors. Therefore, finding alternative parameters reacting to stressors, such as acute phase proteins, would be of great value for the objective evaluation of level of stress and meat quality. As the stress during pre-slaughter handling is unavoidable, the final goal is to improve transport and slaughter conditions for the animal and, as a consequence, meat quality and animal welfare.

  2. Pre-Inflationary Relics in the CMB?

    CERN Document Server

    Gruppuso, A.; Mandolesi, N.; Natoli, P.; Sagnotti, A.

    String Theory and Supergravity allow, in principle, to follow the transition of the inflaton from pre-inflationary fast roll to slow roll. This introduces an infrared depression in the primordial power spectrum that might have left an imprint in the CMB anisotropy, if it occurred at accessible wavelengths. We model the effect extending $\\Lambda$CDM with a scale $\\Delta$ related to the infrared depression and explore the constraints allowed by {\\sc Planck} data, employing also more conservative, wider Galactic masks in the low resolution CMB likelihood. In an extended mask with $f_{sky}=39\\%$, we thus find $\\Delta = (0.351 \\pm 0.114) \\times 10^{-3} \\, \\mbox{Mpc}^{-1}$, at $99.4\\%$ confidence level, to be compared with a nearby value at $88.5\\%$ with the standard $f_{sky}=94\\%$ mask. With about 64 $e$--folds of inflation, these values for $\\Delta$ would translate into primordial energy scales ${\\cal O}(10^{14})$ GeV.

  3. Construction practices in pre-Hispanic flutes

    Science.gov (United States)

    Rawcliffe, Susan

    2002-11-01

    The ancient cultures of the Americas were separated by thousands of miles and thousand of years. There was a long history of trade over the miles and the years with many shared cultural ideals and artifacts, as evidenced by their musical instruments. Flutes were the most prevalent instruments found throughout the ancient Americas. Some types are unique to the pre-Hispanic world. Although flutes were constructed from a variety of materials, including bone, cane, seed pods, skulls, it is primarily the ceramic ones that survived, and it is ceramic flutes which form the bulk of this writer's work and research. This paper includes musical demonstrations to show how ancient flutemakers could have manipulated timbre during construction. Clay's plasticity enabled the construction of some instruments, and limited the development of others. Pitch jump flutes, certain Veracruzano whistles, and chamberduct flutes and whistles all share the addition of clay flaps or chambers around the aperture, as do hooded pipes. Some instruments exhibit a seemingly cultural predilection for complex tones that are windy, raspy, or animalistic. Simple adjustments of the airduct promote these timbres. Also included will be samples of the original sounds of ancient flutes.

  4. The pre-history of urban scaling.

    Science.gov (United States)

    Ortman, Scott G; Cabaniss, Andrew H F; Sturm, Jennie O; Bettencourt, Luís M A

    2014-01-01

    Cities are increasingly the fundamental socio-economic units of human societies worldwide, but we still lack a unified characterization of urbanization that captures the social processes realized by cities across time and space. This is especially important for understanding the role of cities in the history of human civilization and for determining whether studies of ancient cities are relevant for contemporary science and policy. As a step in this direction, we develop a theory of settlement scaling in archaeology, deriving the relationship between population and settled area from a consideration of the interplay between social and infrastructural networks. We then test these models on settlement data from the Pre-Hispanic Basin of Mexico to show that this ancient settlement system displays spatial scaling properties analogous to those observed in modern cities. Our data derive from over 1,500 settlements occupied over two millennia and spanning four major cultural periods characterized by different levels of agricultural productivity, political centralization and market development. We show that, in agreement with theory, total settlement area increases with population size, on average, according to a scale invariant relation with an exponent in the range [Formula: see text]. As a consequence, we are able to infer aggregate socio-economic properties of ancient societies from archaeological measures of settlement organization. Our findings, from an urban settlement system that evolved independently from its old-world counterparts, suggest that principles of settlement organization are very general and may apply to the entire range of human history.

  5. Performance of the LHC Pre-Injectors

    CERN Document Server

    Benedikt, Michael; Chanel, M; Garoby, R; Giovannozzi, Massimo; Hancock, S; Martini, M; Métral, Elias; Métral, G; Schindl, Karlheinz; Vallet, J L

    2001-01-01

    The LHC pre-injector complex, comprising Linac 2, the PS Booster (PSB) and the PS, has undergone a major upgrade in order to meet the very stringent requirements of the LHC. Whereas bunches with the nominal spacing and transverse beam brightness were already available from the PS in 1999 [1], their length proved to be outside tolerance due to a debunching procedure plagued by microwave instabilities. An alternative scenario was then proposed, based on a series of bunch-splitting steps in the PS. The entire process has recently been implemented successfully, and beams whose longitudinal characteristics are safely inside LHC specifications are now routinely available. Variants of the method also enable bunch trains with gaps of different lengths to be generated. These are of interest for the study and possible cure of electron cloud effects in both the SPS and LHC. The paper summarizes the beam dynamics issues that had to be addressed to produce beams with all the requisite qualities for the LHC.

  6. The pre-history of urban scaling.

    Directory of Open Access Journals (Sweden)

    Scott G Ortman

    Full Text Available Cities are increasingly the fundamental socio-economic units of human societies worldwide, but we still lack a unified characterization of urbanization that captures the social processes realized by cities across time and space. This is especially important for understanding the role of cities in the history of human civilization and for determining whether studies of ancient cities are relevant for contemporary science and policy. As a step in this direction, we develop a theory of settlement scaling in archaeology, deriving the relationship between population and settled area from a consideration of the interplay between social and infrastructural networks. We then test these models on settlement data from the Pre-Hispanic Basin of Mexico to show that this ancient settlement system displays spatial scaling properties analogous to those observed in modern cities. Our data derive from over 1,500 settlements occupied over two millennia and spanning four major cultural periods characterized by different levels of agricultural productivity, political centralization and market development. We show that, in agreement with theory, total settlement area increases with population size, on average, according to a scale invariant relation with an exponent in the range [Formula: see text]. As a consequence, we are able to infer aggregate socio-economic properties of ancient societies from archaeological measures of settlement organization. Our findings, from an urban settlement system that evolved independently from its old-world counterparts, suggest that principles of settlement organization are very general and may apply to the entire range of human history.

  7. Promoting Pre-college Science Education

    Science.gov (United States)

    Lee, R. L.

    1999-11-01

    The Fusion Education Program, with support from DOE, continues to promote pre-college science education for students and teachers using multiple approaches. An important part of our program is direct scientist-student interaction. Our ``Scientist in a Classroom'' program allows students to interact with scientists and engage in plasma science activities in the students' classroom. More than 1000 students from 11 schools have participated in this exciting program. Also, this year more than 800 students and teachers have visited the DIII--D facility and interacted with scientists to cover a broad range of technical and educational issues. Teacher-scientist interaction is imperative in professional development and each year more than 100 teachers attend workshops produced by the fusion education team. We also participate in unique learning opportunities. Members of the team, in collaboration with the San Diego County Office of Education, held a pioneering Internet-based Physics Olympiad for American and Siberian students. Our teamwork with educators helps shape material that is grade appropriate, relevant, and stimulates thinking in educators and students.

  8. Plato: from Socrates to Pre-Socratics?

    Directory of Open Access Journals (Sweden)

    YU. SHICHALIN

    2015-04-01

    Full Text Available The traditional view on the chronology of the Corpus Platonicum (CP texts turns out to be anachronistic from several, especially formal and historical, points of view. From the formal point of view all the CP texts can be divided into speeches, framed dialogues and dialogues in dramatic form; there are serious reasons for correlating these groups of dialogues with different chronological periods. Historically, to view Plato’s works as modern philosophical and scholarly literature is incorrect; instead, it would seem expedient to correlate the three groups of dialogues mentioned with their changing audiences for which Plato wrote before the establishment of the Academy, during the first stage of its existence (before the second trip to Sicily and in the later period. The evolution of Plato’s philosophy is to be correlated with the evolution of the school created by him. Lack of attention to these methods can lead to incorrect assumptions concerning Plato’s evolution which found their way, among others, into the book “Plato and the Post-Socratic Dialogue” by Prof. Ch. Kahn where he speaks of a transition from Socratic to Pre-Socratic problems in Plato’s works; the book is critically examined by the author of the present article.

  9. Comparing Binaural Pre-processing Strategies II

    Directory of Open Access Journals (Sweden)

    Regina M. Baumgärtel

    2015-12-01

    Full Text Available Several binaural audio signal enhancement algorithms were evaluated with respect to their potential to improve speech intelligibility in noise for users of bilateral cochlear implants (CIs. 50% speech reception thresholds (SRT50 were assessed using an adaptive procedure in three distinct, realistic noise scenarios. All scenarios were highly nonstationary, complex, and included a significant amount of reverberation. Other aspects, such as the perfectly frontal target position, were idealized laboratory settings, allowing the algorithms to perform better than in corresponding real-world conditions. Eight bilaterally implanted CI users, wearing devices from three manufacturers, participated in the study. In all noise conditions, a substantial improvement in SRT50 compared to the unprocessed signal was observed for most of the algorithms tested, with the largest improvements generally provided by binaural minimum variance distortionless response (MVDR beamforming algorithms. The largest overall improvement in speech intelligibility was achieved by an adaptive binaural MVDR in a spatially separated, single competing talker noise scenario. A no-pre-processing condition and adaptive differential microphones without a binaural link served as the two baseline conditions. SRT50 improvements provided by the binaural MVDR beamformers surpassed the performance of the adaptive differential microphones in most cases. Speech intelligibility improvements predicted by instrumental measures were shown to account for some but not all aspects of the perceptually obtained SRT50 improvements measured in bilaterally implanted CI users.

  10. Pre- and postmortem imaging of transplanted cells

    Directory of Open Access Journals (Sweden)

    Andrzejewska A

    2015-09-01

    Full Text Available Anna Andrzejewska,1 Adam Nowakowski,1 Miroslaw Janowski,1–4 Jeff WM Bulte,3–7 Assaf A Gilad,3,4 Piotr Walczak,3,4,8 Barbara Lukomska11NeuroRepair Department, 2Department of Neurosurgery, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland; 3Russell H Morgan Department of Radiology and Radiological Science, Division of MR Research, 4Cellular Imaging Section and Vascular Biology Program, Institute for Cell Engineering, 5Department of Biomedical Engineering, 6Department of Chemical & Biomolecular Engineering, 7Department of Oncology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; 8Department of Radiology, Faculty of Medical Sciences, University of Warmia and Mazury, Olsztyn, PolandAbstract: Therapeutic interventions based on the transplantation of stem and progenitor cells have garnered increasing interest. This interest is fueled by successful preclinical studies for indications in many diseases, including the cardiovascular, central nervous, and musculoskeletal system. Further progress in this field is contingent upon access to techniques that facilitate an unambiguous identification and characterization of grafted cells. Such methods are invaluable for optimization of cell delivery, improvement of cell survival, and assessment of the functional integration of grafted cells. Following is a focused overview of the currently available cell detection and tracking methodologies that covers the entire spectrum from pre- to postmortem cell identification.Keywords: stem cells, transplantation, SPECT, MRI, bioluminescence, cell labeling

  11. Optimizing pre-service inspection data

    International Nuclear Information System (INIS)

    Mullins, L.E.; Harrison, J.M.

    1986-01-01

    The phenomenon of intergranular stress corrosion cracking (IGSCC) in nuclear power plant piping systems has been the single biggest factor in an evolution that has changed and continues to change in-service inspection practices and philosophy throughout the industry. In-service inspection has been found to deal with several distinct phases of the problem. At the onset, existing technology was demonstrated to be unable to detect IGSCC adequately. This inability to detect IGSCC was soon overcome. However, it immediately pointed out the difficulties associated with the discrimination between IGSCC and other harmless metallurgical conditions. On the heels of detection and discrimination came problems associated with determining crack size and the monitoring of overlayed flaws. A wealth of information has been written on all phases of IGSCC; however, one particular aspect has as of yet seen little attention. With an increasing number of plants choosing to replace flawed pipe, the pre-service inspection of the replaced piping demands increased attention. The lessons learned through inspection for IGSCC need again to be applied to the replacement piping. Through increased attention at installation, many of the difficulties associated with proper inservice inspection may be reduced or eliminated, thereby realizing an economy in outage scheduling, personnel exposure, and, overall, a more reliable in-service examination

  12. Statewide Inferior Vena Cava Filter Placement, Complications, and Retrievals: Epidemiology and Recent Trends.

    Science.gov (United States)

    Charalel, Resmi A; Durack, Jeremy C; Mao, Jialin; Ross, Joseph S; Meltzer, Andrew J; Sedrakyan, Art

    2018-03-01

    Public awareness of inferior vena cava (IVC) filter-related controversies has been elevated by the Food and Drug Administration (FDA) safety communication in 2010. To examine population level trends in IVC filter utilization, complications, retrieval rates, and subsequent pulmonary embolism (PE) risk. A retrospective cohort study. Patients receiving IVC filters during 2005-2014 in New York State. IVC filter-specific complications, new PE occurrences and IVC filter retrievals were evaluated as time-to-event data using Kaplan-Meier analysis. Estimated cumulative risks were obtained at various timepoints during follow-up. There were 91,873 patients receiving IVC filters between 2005 and 2014 in New York State included in the study. The average patient age was 67 years and 46.6% were male. Age-adjusted rates of IVC filter placement increased from 48 cases/100,000 in 2005 to 52 cases/100,000 in 2009, and decreased afterwards to 36 cases/100,000 in 2014. The estimated risks of having an IVC filter-related complication and filter retrieval within 1 year was 1.5% [95% confidence interval (CI), 1.4%-1.6%] and 3.5% (95% CI, 3.4%-3.6%). One-year retrieval rate was higher post-2010 when compared with pre-2010 years (hazard ratio, 2.70; 95% CI, 2.50-2.91). Among the 58,176 patients who did not have PE events before or at the time of IVC filter placement, the estimated risk of developing subsequent PE at 1 year was 2.0% (95% CI, 1.9%-2.1%). Our findings suggest that FDA communications may be effective in modifying statewide clinical practices. Given the 2% observed PE rate following prophylactic IVC filter placement, large scale pragmatic studies are needed to determine contemporary safety and effectiveness of IVC filters.

  13. Pre-eclampsia: a life-threatening pregnancy syndrom

    Directory of Open Access Journals (Sweden)

    Andrea Brazdova

    2014-10-01

    Full Text Available Pre-eclampsia is a serious pathological state affecting 5-10% of pregnant women. Currently, it is diagnosed in the second half of pregnancy, particularly after the 20th week. Symptoms mostly correspond to the changes of blood vessels and kidneys. The severity of pre-eclampsia is proportional to symptomatic manifestations, thus the more symptoms present, the higher is of pre-eclampsia development. Although there are several studies dealing with pre-eclampsia pathology, the complete etiology is still unknown. In this review paper, several theories are presented and discussed.

  14. Pre-Conflict Management Tools: Winning the Peace

    National Research Council Canada - National Science Library

    Frank, Aaron B

    2005-01-01

    The Pre-Conflict Management Tools (PCMT) Program was developed to transform how intelligence analysts, policy analysts, operational planners, and decisionmakers interact when confronting highly complex strategic problems...

  15. Basic math and pre-algebra practice problems for dummies

    CERN Document Server

    Zegarelli, Mark

    2013-01-01

    1001 Basic Math & Pre- Algebra Practice Problems For  Dummies   Practice makes perfect-and helps deepen your understanding of basic math and pre-algebra 1001 Basic Math & Pre-Algebra Practice Problems For Dummies, with free access to online practice problems, takes you beyond the instruction and guidance offered in Basic Math & Pre-Algebra For Dummies, giving you 1,001 opportunities to practice solving problems from the major topics in your math course. You begin with some basic arithmetic practice, move on to fractions, decimals, and per

  16. CULTURAL INFLUENCES ON PRE-PAY MOBILE TELECOMMUNICATIONS SERVICES USERS

    Directory of Open Access Journals (Sweden)

    Georgeta-Madalina MEGHISAN

    2015-06-01

    Full Text Available Purpose: The purpose of this research paper is to identify the preferences of the pre-pay mobile telecommunications services young users from Romania. Approach/ methodology: The analysis of the pre-pay mobile telecommunications services was made using statistical functions: descriptive statistics, t test, correlation and factor analysis. Results: According to the analysis made, we could underline the habits of usage from the part of pre-pay mobile telecommunications services consumers. Originality: The paper drew an objective analysis on the pre-pay mobile telecommunications services from the perspective of young consumers.

  17. Pre-employment medical testing in Brazil: ethical challenges.

    Science.gov (United States)

    Palhares, Dario; Laurentino dos Santos, Ivone

    2012-01-01

    Pre-employment medical tests, considered to be a practice within the subspecialty of occupational medicine, are ordered by physicians on behalf of employers. Candidates for a job may be rejected if they are found to suffer from a condition that can be worsened by the job, or one that may put other workers at risk. As the physician who orders pre-employment tests is chosen by the employer, pre-employment tests can violate both the autonomy and the privacy of the individual. This paper discusses ethical conflicts inherent in pre-employment medical testing.

  18. Tine after tine: a varied approach to the removal of a long-standing IVC filter

    Directory of Open Access Journals (Sweden)

    Andrew Delozier

    2017-06-01

    Full Text Available Inferior vena cava filters are important tools used to help prevent life-threatening pulmonary embolisms in hospitalized patients with contraindications to pharmacological prophylactic anticoagulation. This is a case report of a patient who had an inferior vena cava filter placed after a traumatic subdural hematoma. He made a complete recovery but was lost to follow-up until he presented 1825 days after filter deployment with abdominal pain discovered to be from penetration of the filter tines outside the lumen and into adjacent structures. We describe a case complicated by fibrotic tine entrapment with penetration to surrounding structures and discuss the technical approach used to free and eventually remove the long-standing filter.

  19. Congenital absence of infrarenal IVC and iliac venous system : Unusual collateral Pathways

    International Nuclear Information System (INIS)

    Lee, Jin Joo; Lee, Byung Hee; Kim, Kie Hwan; Do, Young Soo; Chin, Soo Yil

    1994-01-01

    We present a case with congenital absence of the infrarenal portion of inferior vena cava and iliac venous system, showing unusual venous collaterals including the left ovarian venous collateral via parametrial venous complex, and a mesenteric-periureteric venous connection. The venous collateral pathways were demonstrated by computed tomography and venography

  20. Instructional Coding System for Mathematics Program of Studies. MET, A Title IV-C Project.

    Science.gov (United States)

    Fairfax County Public Schools, VA. Dept. of Instructional Services.

    This document is part of the Management for Effective Teaching (MET) support kit, a pilot project designed by the Fairfax County (Virginia) Public Schools to assist elementary school teachers in planning, managing, and implementing the county's Program of Studies (POS). This document provides an alpha-numeric coding system to be used in…

  1. New optional IVC filter for percutaneous retrieval - in vitro evaluation of embolus capturing efficiency

    International Nuclear Information System (INIS)

    Guenther, R.W.; Mossdorf, A.; Pfeffer, J.; Buecker, A.; Neuerburg, J.; Hoej, A.R.; Moelgaard-Nielsen, A.; Schmitz-Rode, T.

    2005-01-01

    Purpose: In-vitro evaluation of a new caval filter (Cook Celect Filter) developed for delayed percutaneous retrieval in comparison to the Guenther Tulip filter. Materials and Methods: The new Celect filter is constructed on the basis of the Tulip filter and consists of 4 primary anchoring legs and additional 8 thinner secondary wires to stabilize the filter and to guarantee adequate filtering efficiency. The filtering wires are of the same amount and equal distribution as the filtering wires of the Tulip filter. The secondary wires are arranged in such a way that percutaneous filter retrieval should be possible even if the wires are incorporated into the caval wall. In a flow model (tube size diameter 15-, diameter 22- and diameter 30 mm), the filter was exposed to single and multiple emboli (blood clots) of different sizes (3 x 5, 3 x 10, 5 x 10, 3 x 20, 5 x 20, 7 x 10, 7 x 20 to 10 x 24 mm) to analyse the embolus capturing efficiency under different conditions including eccentric and concentric, horizontal and vertical positions in comparison to the Tulip filter. All testing was carried out in SPSS analytic software; statistical significance was assumed for p-values <0.05. Results: The in-vitro embolus capturing efficiency of the Celect filter proved to be equivalent to the Tulip filter. In the single-embolus test, 91.6% of the clots were captured by the Celect filter and 87.2% by the Tulip filter (p=0.042). Large clots ranging from 7 x 10 to 10 x 24 mm were captured in all cases, whereas the capture rates for the 3 x 5-mm and 3 x 10-mm clots were lower. The filters captured significantly more clots in the concentric than in the eccentric location. There was no significant difference between the overall capture rates of the two filters in the multi-clot test (72.2% vs. 75.1%), which showed deterioration of filter function during multiple clot exposure. With the 15-mm tube, the Celect filter had a significantly higher capture rate than the Tulip filter, whereas it was lower with the diameter 30-mm tube. There was no significant difference between the filters in a diameter 22-mm tube. The pressure gradient across the filters when exposed to blood clots ranged from 4.9-7.4 mm Hg for the Celect filter and 5.7-6.8 mm Hg for the Tulip filter in the single-embolus testing. There was no significant difference in the multi-clot tests. Conclusion: The new Celect filter showed similar in-vitro capture properties as the Guenther Tulip filter and deserves further in-vivo testing. (orig.)

  2. Instrument pre-development activities for FLEX

    Science.gov (United States)

    Pettinato, L.; Fossati, E.; Coppo, P. M.; Taiti, A.; Labate, D.; Capanni, A.; Taccola, M.; Bézy, J. L.; Francois, M.; Meynart, R.; Erdmann, L.; Triebel, P.

    2017-09-01

    The FLuorescence Imaging Spectrometer (FLORIS) is the payload of the FLuorescence Explorer Mission (FLEX) of the European Space Agency. The mission objective is to perform quantitative measurements of the solar induced vegetation fluorescence to monitor photosynthetic activity. FLORIS works in a push-broom configuration and it is designed to acquire data in the 500-780 nm spectral range, with a sampling of 0.1 nm in the oxygen bands (759-769 nm and 686- 697 nm) and 0.5-2.0 nm in the red edge, chlorophyll absorption and Photochemical Reflectance Index bands. FLEX will fly in formation with Sentinel-3 to benefit of the measurements made by the Sentinel-3 instruments OLCI and SLSTR, particularly for cloud screening, proper characterization of the atmospheric state and determination of the surface temperature. The instrument concept is based on a common telescope and two modified Offner spectrometers with reflective concave gratings both for the High Resolution (HR) and Low Resolution (LR) spectrometers. In the frame of the instrument pre-development Leonardo Company (I) has built and tested an elegant breadboard of the instrument consisting of the telescope and the HR spectrometer. The development of the LR spectrometer is in charge of OHB System AG (D) and is currently in the manufacturing phase. The main objectives of the activity are: anticipate the development of the instrument and provide early risk retirement of critical components, evaluate the system performances such as imaging quality parameters, straylight, ghost, polarization sensitivity and environmental influences, verify the adequacy of critical tests such as spectral characterization and straylight, define and optimize instrument alignment procedures. Following a brief overview of the FLEX mission, the paper will cover the design and the development of the optics breadboard with emphasis on the results obtained during the tests and the lessons learned for the flight unit.

  3. Pre-relaxation in weakly interacting models

    Science.gov (United States)

    Bertini, Bruno; Fagotti, Maurizio

    2015-07-01

    We consider time evolution in models close to integrable points with hidden symmetries that generate infinitely many local conservation laws that do not commute with one another. The system is expected to (locally) relax to a thermal ensemble if integrability is broken, or to a so-called generalised Gibbs ensemble if unbroken. In some circumstances expectation values exhibit quasi-stationary behaviour long before their typical relaxation time. For integrability-breaking perturbations, these are also called pre-thermalisation plateaux, and emerge e.g. in the strong coupling limit of the Bose-Hubbard model. As a result of the hidden symmetries, quasi-stationarity appears also in integrable models, for example in the Ising limit of the XXZ model. We investigate a weak coupling limit, identify a time window in which the effects of the perturbations become significant and solve the time evolution through a mean-field mapping. As an explicit example we study the XYZ spin-\\frac{1}{2} chain with additional perturbations that break integrability. One of the most intriguing results of the analysis is the appearance of persistent oscillatory behaviour. To unravel its origin, we study in detail a toy model: the transverse-field Ising chain with an additional nonlocal interaction proportional to the square of the transverse spin per unit length (2013 Phys. Rev. Lett. 111 197203). Despite being nonlocal, this belongs to a class of models that emerge as intermediate steps of the mean-field mapping and shares many dynamical properties with the weakly interacting models under consideration.

  4. Nutrition in pre-war Sarajevo.

    Science.gov (United States)

    Zec, S; Telebak, B; Sljepcevic, O; Filipovic-Hadziomeragic, A

    1995-10-01

    To assess nutritional status, dietary intake and lifestyle habits of non-manual workers in Sarajevo. Healthy employees in non-manual occupations from four large companies were invited to participate in a nutrition and health survey during 1990 and 1991. All the subjects were working in the city centre of Sarajevo. 1860 subjects (1120 men and 740 women) aged from 20-65 years of age participated. Nutritional status was evaluated through anthropometric measurements (weights and heights) and body mass index (BMI) was calculated. Data on health status, diet and lifestyle were gathered through individual questionnaires. Overall, 4.3% of the sample was found to be underweight (BMI 30.5). The majority of the obese men were in responsible positions (for example, directors, heads of departments). The majority of obese women were in the 35-45 years old age group in the post-maternity period. Intakes of energy, protein, fat and carbohydrate exceeded former Yugoslavian recommended dietary allowances. About one third of participants (34.3% men and 27.3% women) smoked heavily and 18.1% of men drank alcohol. A total of 16.2% of men and 11.6% of women suffered from hypertension. The food intake of the population of Sarajevo before the war was generally high. There was high consumption of meat, fatty foods and alcoholic drinks (particularly among men) and low levels of physical activity. This resulted in high levels of obesity and chronic degenerative diseases such as hypertension. Thus, high living standards and physical inactivity had a damaging effect on the health of non-manual workers in pre-war Sarajevo.

  5. Bats and wind turbines : pre-siting and pre-construction survey protocols

    Energy Technology Data Exchange (ETDEWEB)

    Lausen, C.; Baerwald, E.; Gruver, J.; Barclay, R. [Calgary Univ., AB (Canada)

    2008-05-15

    Studies have shown that a number of bats are killed by moving wind turbine blades at wind farms throughout North America. The studies have shown that over 80 per cent of the fatalities involve migratory bat species. Hoary bats, eastern red bats, and silver-haired bats dominate the fatalities during the fall migration period. Fatality rates vary among wind energy developments. Some data suggest that fatalities are higher on nights with lower wind speeds, and increased fatalities have been associated with taller wind turbines. This report outlined pre-construction survey requirements for preventing bat fatalities at wind power plants. A pre-construction survey was recommended to achieve a representative sampling of bat activity and determine the relative risk to bats. The study suggested that monitoring data from locations across the province should be pooled to provide a better understanding of the landscape-scale patterns of bat migration. Monitoring for bats should be conducted continuously due to the sporadic nature of peaks in bat activity, the influence of temperature, moon phase, and weather variables. Sampling techniques for acoustic detection, radar tracking, and mist-netting should be implemented to determine the abundance of susceptible species and the location of migration routes. All existing meteorological towers should be used as sampling stations with bat detectors installed at ground level and near the top of the tower. Additional detector stations should be distributed throughout the wind resource area. Specialized anabat microphones should be calibrated to record bat activity. Acoustic data should be presented as total bat passes and mean passes per night and matched with corresponding meteorological data. It was concluded that pre-construction monitoring data should be gathered and made available for collaborative and cumulative research efforts. 28 refs., 1 fig.

  6. Effectiveness of different pre-treatments in recovering pre-burial isotopic ratios of charred plants.

    Science.gov (United States)

    Brinkkemper, O; Braadbaart, F; van Os, B; van Hoesel, A; van Brussel, A A N; Fernandes, R

    2018-02-15

    Isotopic analysis of archaeological charred plant remains offers useful archaeological information. However, adequate sample pre-treatment protocols may be necessary to provide a contamination-free isotopic signal while limiting sample loss and achieving a high throughput. Under these constraints, research was undertaken to compare the performance of different pre-treatment protocols. Charred archaeological plant material was selected for isotopic analysis (δ 13 C and δ 15 N values) by isotope ratio mass spectrometry from a variety of plant species, time periods and soil conditions. Preservation conditions and the effectiveness of cleaning protocols were assessed through Fourier transform infrared spectroscopy and X-ray fluorescence (XRF) spectrometry. An acid-base-acid protocol, successfully employed in radiocarbon dating, was used to define a contamination-free isotopic reference. Acid-base-acid isotopic measurements were compared with those obtained from untreated material and an acid-only protocol. The isotopic signals of untreated material and the acid-only protocol typically did not differ more than 1‰ from those of the acid-base-acid reference. There were no significant isotopic offsets between acid-base-acid and acid-only or untreated samples. Sample losses in the acid-base-acid protocol were on average 50 ± 17% (maximum = 98.4%). Elemental XRF measurements showed promising results in the detection of more contaminated samples albeit with a high rate of false positives. For the large range of preservation conditions described in the study, untreated charred plant samples, water cleaned of sediments, provide reliable stable isotope ratios of carbon and nitrogen. The use of pre-treatments may be necessary under different preservation conditions or more conservative measurement uncertainties should be reported. Copyright © 2017 John Wiley & Sons, Ltd.

  7. Vena Cava Filter Retrieval with Aorto-Iliac Arterial Strut Penetration.

    Science.gov (United States)

    Holly, Brian P; Gaba, Ron C; Lessne, Mark L; Lewandowski, Robert J; Ryu, Robert K; Desai, Kush R; Sing, Ronald F

    2018-05-03

    To evaluate the safety and technical success of inferior vena cava (IVC) filter retrieval in the setting of aorto-iliac arterial strut penetration. IVC filter registries from six large United States IVC filter retrieval practices were retrospectively reviewed to identify patients who underwent IVC filter retrieval in the setting of filter strut penetration into the adjacent aorta or iliac artery. Patient demographics, implant duration, indication for placement, IVC filter type, retrieval technique and technical success, adverse events, and post procedural clinical outcomes were identified. Arterial penetration was determined based on pre-procedure CT imaging in all cases. The IVC filter retrieval technique used was at the discretion of the operating physician. Seventeen patients from six US centers who underwent retrieval of an IVC filter with at least one strut penetrating either the aorta or iliac artery were identified. Retrieval technical success rate was 100% (17/17), without any major adverse events. Post-retrieval follow-up ranging from 10 days to 2 years (mean 4.6 months) was available in 12/17 (71%) patients; no delayed adverse events were encountered. Findings from this series suggest that chronically indwelling IVC filters with aorto-iliac arterial strut penetration may be safely retrieved.

  8. Comparative Study of Pre-Germination Treatments and their Effects ...

    African Journals Online (AJOL)

    FIRST LADY

    of leaves (10.05) respectively. Pre-germination treatments of seeds soaked in running water (SRW) for 24 hours were found to be more effective in seedlings growth and biomass production. Keywords: Tectona grandis, pre-germination treatment, seed dormancy, seedling growth. Introduction. Tectona grandis is one of the ...

  9. Early pre-eclampsia unmasks underlying IgA nephropathy

    Directory of Open Access Journals (Sweden)

    Mona Singh

    2010-12-01

    Full Text Available Mona Singh, Akhenaton Pappoe, Burl R DonDivision of Nephrology, University of California Davis Medical Center, Sacramento, CA, USAAbstract: Pre-eclampsia is the most ominous complication of pregnancy, and primary glomerular diseases can mimic pre-eclampsia in presentation. A patient presented at 21 weeks gestation with signs and symptoms of both pre-eclampsia and primary glomerular nephropathy. A critical clinical decision whether to continue or terminate the pregnancy was dependent on results of a renal biopsy. The biopsy noted the presence of both pre-eclampsia and immunoglobulin A (IgA nephropathy. Thus, the onset of pre-eclampsia unmasked the presence of unrecognized IgA nephropathy, and the IgA nephropathy was a risk factor for this patient developing pre-eclampsia. The results of a renal biopsy are key in distinguishing pre-eclampsia from other kidney diseases and instituting appropriate clinical management.Keywords: proteinuria, IgA nephropathy, renal biopsy, pre-eclampsia

  10. 24 CFR 108.15 - Pre-occupancy conference.

    Science.gov (United States)

    2010-04-01

    ... plan and may schedule a pre-occupancy conference. Such pre-occupancy conference shall be held prior to initiation of sales or rental marketing activities. At this conference, the previously approved AFHM plan... days prior to engaging in sales or rental marketing activities. Upon receipt of the Notification of...

  11. 40 CFR 89.406 - Pre-test procedures.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Pre-test procedures. 89.406 Section 89.406 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... Procedures § 89.406 Pre-test procedures. (a) Allow a minimum of 30 minutes warmup in the standby or operating...

  12. Examination of Pre-Service Teacher's Training through Tutoring Approach

    Science.gov (United States)

    Wu, Hsiao-ping; Guerra, Myriam Jimena

    2017-01-01

    Pre-service teacher preparation in the United States is becoming progressively more challenging with respect to the demands on teachers. This study examined the impact of tutoring approach on pre-service teachers? skills to work with English language learners through a qualitative research design. Content analysis was used at the thematic level on…

  13. Pre-Service Teachers' Concept Images on Fractal Dimension

    Science.gov (United States)

    Karakus, Fatih

    2016-01-01

    The analysis of pre-service teachers' concept images can provide information about their mental schema of fractal dimension. There is limited research on students' understanding of fractal and fractal dimension. Therefore, this study aimed to investigate the pre-service teachers' understandings of fractal dimension based on concept image. The…

  14. Opportunities to Align California's PreK-3 Education System

    Science.gov (United States)

    Policy Analysis for California Education, PACE, 2016

    2016-01-01

    "PreK-3 Alignment in California's Education System: Obstacles and Opportunities" by Rachel Valentino and Deborah J. Stipek reviews the opportunities and challenges that must be addressed to better align PreK-3 education in California. The report describes policies and practices that districts have implemented to strengthen alignment, and…

  15. Measuring the Economic Value of Pre-MBA Work Experience

    Science.gov (United States)

    Yeaple, Ronald N.; Johnston, Mark W.; Whittingham, Keith L.

    2010-01-01

    Pre-MBA work experience is required for admission to many graduate schools of business. In the present study, MBA graduates with a wide range of pre-MBA work experience were surveyed to assess the economic value of such work experience. No evidence was found of a systematic financial advantage to students from working for several years before…

  16. Linking pre-meeting communication to meeting effectiveness

    NARCIS (Netherlands)

    Allen, J.A.; Lehmann-Willenbrock, N.K.; Landowski, N.

    2014-01-01

    Purpose – The purpose of this paper is to investigate the importance of communication that occurs just before workplace meetings (i.e. pre-meeting talk). The paper explores how four specific types of pre-meeting talk (small talk, work talk, meeting preparatory talk, and shop talk) impact

  17. Technology Acceptance among Pre-Service Teachers: Does Gender Matter?

    Science.gov (United States)

    Teo, Timothy; Fan, Xitao; Du, Jianxia

    2015-01-01

    This study examined possible gender differences in pre-service teachers' perceived acceptance of technology in their professional work under the framework of the technology acceptance model (TAM). Based on a sample of pre-service teachers, a series of progressively more stringent measurement invariance tests (configural, metric, and scalar…

  18. Implementation of Pre-Operative Checklist: An Effort to Reduce ...

    African Journals Online (AJOL)

    Implementation of Pre-Operative Checklist: An Effort to Reduce Delays in. Surgery and ... insight to develop a pre-operative checklist to ensure that patients were prepared for surgery and to minimize disruptions ... documentation audit was conducted in May 2014, showing 59% compliance in completing the checklist. Since.

  19. Pre-Service Physics Teachers' Conceptions of Nature of Science

    Science.gov (United States)

    Buaraphan, Khajornsak

    2011-01-01

    Understanding of NOS (nature of science) appears as a prerequisite of a scientifically literate person. Promoting adequate understanding of NOS in pre-service physics teachers is, therefore, an important task of science educators. Before doing that, science educators must have information concerning their pre-service teachers' conceptions of NOS.…

  20. Algebraic Generalization Strategies Used by Kuwaiti Pre-Service Teachers

    Science.gov (United States)

    Alajmi, Amal Hussain

    2016-01-01

    This study reports on the algebraic generalization strategies used by elementary and middle/high school pre-service mathematics teachers in Kuwait. They were presented with 9 tasks that involved linear, exponential, and quadratic situations. The results showed that these pre-service teachers had difficulty in generalizing algebraic rules in all 3…

  1. 14 CFR 414.9 - Pre-application consultation.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Pre-application consultation. 414.9 Section 414.9 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING SAFETY APPROVALS Application Procedures § 414.9 Pre-application...

  2. 14 CFR 413.5 - Pre-application consultation.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Pre-application consultation. 413.5 Section 413.5 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING LICENSE APPLICATION PROCEDURES § 413.5 Pre-application consultation. A...

  3. Investigation of Pre-Service Teachers' Communication Skills

    Science.gov (United States)

    Kana, Fatih

    2015-01-01

    The purpose of this study is to determine the levels of Turkish language pre-service teachers' communication skills. Descriptive survey model was used in this study. 218 pre-service Turkish language teachers, who are studying at Department of Turkish Language Teaching at a university in the west of Turkey, participated in the study. Criterion…

  4. Figure 1. Associations between pre-ART clinical and laboratory ...

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Figure 1. Associations between pre-ART clinical and laboratory characteristics with subsequent TB-IRIS events. Figure 1. Associations between pre-ART clinical and laboratory characteristics with subsequent TB-IRIS events.

  5. 26 CFR 1.679-5 - Pre-immigration trusts.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Pre-immigration trusts. 1.679-5 Section 1.679-5 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Grantors and Others Treated As Substantial Owners § 1.679-5 Pre-immigration trusts. (a) In...

  6. Pre-Service Teachers' Mental Models of Basic Astronomy Concepts

    Science.gov (United States)

    Arslan, A. Saglam; Durikan, U.

    2016-01-01

    The aim of the present study is to determine pre-service teachers' mental models related to basic astronomy concepts. The study was conducted using a survey method with 293 pre-service teachers from 4 different departments; physics education, science education, primary teacher education and early childhood education. An achievement test with…

  7. Serum Magnesium Levels in Non-Pregnant, Pregnant And Pre ...

    African Journals Online (AJOL)

    The objective of this study was to compare the serum magnesium levels in normal pregnancy and pregnancy complicated by pre-eclampsia since magnesium has been implicated in the pathogenesis of vascular dysfunction. We measured serum magnesium levels in patients with pre-eclampsia (n=36), patients with normal ...

  8. Periodontal disease and pre-eclampsia : a systematic review

    NARCIS (Netherlands)

    Kunnen, Alina; van Doormaal, Jasper J.; Abbas, Frank; Aarnoudse, Jan G.; van Pampus, Maria; Faas, Marijke M.

    2010-01-01

    P>Aim This review evaluates the possible relationship between periodontal disease and pre-eclampsia, a major pregnancy complication. A generalized inflammatory response plays an important role in the pathogenesis of pre-eclampsia. Because periodontal disease is a low-grade inflammatory state,

  9. Periodontal disease and pre-eclampsia: a systematic review.

    Science.gov (United States)

    Kunnen, Alina; van Doormaal, Jasper J; Abbas, Frank; Aarnoudse, Jan G; van Pampus, Maria G; Faas, Marijke M

    2010-12-01

    This review evaluates the possible relationship between periodontal disease and pre-eclampsia, a major pregnancy complication. A generalized inflammatory response plays an important role in the pathogenesis of pre-eclampsia. Because periodontal disease is a low-grade inflammatory state, periodontal disease might contribute to the pathogenesis of pre-eclampsia. A literature search of PubMed, EMBASE and CINAHL until August 2010 revealed 12 eligible observational studies and three randomized-controlled trials (RCTs). It appeared difficult to compare these studies, due to variations in definitions of periodontal disease and pre-eclampsia, timing of periodontal examination and inadequate control for confounding factors. Eight observational studies reported a positive association, while four studies found no association. None of the RTCs reported reductions in pre-eclamptic rate after periodontal therapy during pregnancy. Therefore, it is questionable whether periodontal disease plays a causal role in the pathogenesis of pre-eclampsia. The observed association in eight observational studies might be the result of induction of periodontal disease due to the pre-eclamptic state or it may be an epiphenomenon of an exaggerated inflammatory response to pregnancy. Larger RCTs with pre-eclampsia as the primary outcome and pathophysiological studies are required to explore causality and to dissect biological mechanisms involved. © 2010 John Wiley & Sons A/S.

  10. Pre-1970 transuranic solid waste at the Hanford Site

    International Nuclear Information System (INIS)

    Greenhalgh, W.O.

    1995-01-01

    The document is based on a search of pre-1970 Hanford Solid Waste Records. The available data indicates seven out of thirty-one solid waste burial sites used for pre-1970 waste appear to be Transuranic (TRU). A burial site defined to be TRU contains >100 nCi/gm Transuranic nuclides

  11. Preventive effectiveness of pre-employment medical assessments

    NARCIS (Netherlands)

    de Kort, W.; van Dijk, F.

    1997-01-01

    Health gain, prevention of health loss, and avoidance of financial risk all seem to be driving forces for the use of pre-employment medical assessment. An attempt is made to measure the effect of implementing the pre-employment medical assessment on these end points. The anticipated maximum

  12. Pre-School Education in Morocco and Algeria

    Science.gov (United States)

    Bouzoubaa, Khadija; Benghabrit-Remaoun, Nouria

    2004-01-01

    This article is an analysis of the current state of early childhood care in the Maghreb, in particular in Morocco and Algeria, where the pre-schooling rate for 5-year-olds is on the increase. Extending pre-school infrastructures and the need to create unified curricula have been among the most urgent questions to be tackled over the last decade in…

  13. Scale development for pre-service mathematics teachers ...

    African Journals Online (AJOL)

    The purpose of this study is to develop a scale to determine pre-service mathematics teachers' perceptions related to their pedagogical content knowledge. Firstly, a preliminary perception scale of pedagogical content knowledge was constructed and then administered to 112 pre-service mathematics teachers who were ...

  14. Turkish Pre-Service Physics Teachers' Preferred Learning Styles

    Science.gov (United States)

    Kandil Ingec, Sebnem

    2015-01-01

    This study aims to determine the dominant learning styles of pre-service physics teachers and to examine them in terms of variables such as gender, information and communication technologies skills, academic achievement and type of motivation. Survey model was used. The sample composed of 50 pre-service physics teachers. The data were collected…

  15. 20 CFR 655.15 - Required pre-filing recruitment.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Required pre-filing recruitment. 655.15... States (H-2B Workers) § 655.15 Required pre-filing recruitment. (a) Time of filing of application. An... recruitment steps set forth in this section have been fully satisfied, except where specifically exempted from...

  16. Variable volume combustor with pre-nozzle fuel injection system

    Science.gov (United States)

    Keener, Christopher Paul; Johnson, Thomas Edward; McConnaughhay, Johnie Franklin; Ostebee, Heath Michael

    2016-09-06

    The present application provides a combustor for use with a gas turbine engine. The combustor may include a number of fuel nozzles, a pre-nozzle fuel injection system supporting the fuel nozzles, and a linear actuator to maneuver the fuel nozzles and the pre-nozzle fuel injection system.

  17. Pre-service teachers' mathematical knowledge for teaching basic ...

    African Journals Online (AJOL)

    This study measured pre-service teachers' mathematical knowledge for teaching (MKT) basic school mathematics. MKT multiple-choice test was administered to 100 pre-service teachers from two colleges of education (located at Mampong in the Ashanti Region of Ghana) to assess their mathematical knowledge for ...

  18. Pre-Service Secondary Teachers' Attitudes towards Inclusive Education

    Science.gov (United States)

    Costello, Shane; Boyle, Christopher

    2013-01-01

    The attitudes held by pre-service teachers have been shown to affect their willingness and ability to implement an inclusive approach to education. A sample consisting of 193 pre-service secondary teachers enrolled in secondary education courses at an Australian university were surveyed to determine their attitudes towards inclusive education,…

  19. Prediction and primary prevention of pre-eclampsia

    NARCIS (Netherlands)

    Thangaratinam, Shakila; Langenveld, Josie; Mol, Ben W.; Khan, Khalid S.

    2011-01-01

    Pre-eclampsia is associated with increased maternal and perinatal mortality and morbidity. Early recognition of women at risk of pre-eclampsia will enable the identification of high-risk women who may benefit from enhanced surveillance and prophylaxis. In this chapter, we summarise the accuracy of

  20. Thermal Decompositon Studies Of Pre-Irradiated Nickel (II) Azides ...

    African Journals Online (AJOL)

    The effect of pre-irradiation on the thermal decomposition of three samples of nickel (II) azide was studied. It was found that the rates of thermal decomposition of Ni(OH)N3 increased substantially with increase in pre-irradiation dosage. The initial reaction rates change from time-dependant nucleation law for the unirradiated ...

  1. Investigating Classroom Teaching Competencies of Pre Service Elementary Mathematics Teachers

    Science.gov (United States)

    Gokalp, Murat

    2016-01-01

    The study has sought answers to two major questions: What is the current situation in Elementary Mathematics Education programs at Faculty of Education in terms of classroom teaching competencies? To what extent do pre service teachers acquire these competencies? The research was conducted on 202 senior pre service teachers studying at the…

  2. Moving House for Education in the Pre-School Years

    Science.gov (United States)

    Hansen, Kirstine

    2014-01-01

    This paper uses data from the Millennium Cohort Study (MCS) to examine house moves that take place in the pre-school years, focusing on families who move for the education of their children. We present results showing that education- related house moves do indeed occur in the pre-school years with particular types of parents making these…

  3. Inclusion in Early Childhood Education: Pre-Service Teachers Voices

    Science.gov (United States)

    Majoko, Tawanda

    2016-01-01

    This study examined pre-service teachers' understanding, attitudes, preparation and concerns regarding inclusion in early childhood education (ECE) in Zimbabwe. Entrenched within inclusive pedagogy, this descriptive study draws on a sample of 24 pre-service teachers purposively selected from the largest teachers' college with the oldest…

  4. Depression, Fatigue, and Pre-Sleep Arousal: A Mediation Model

    Science.gov (United States)

    Karlson, Cynthia W.; Stevens, Natalie R.; Olson, Christy A.; Hamilton, Nancy A.

    2010-01-01

    Fatigue is a common and debilitating symptom of clinical depression; however, the causes are not well understood. The present study was designed to test the hypotheses that subjective sleep, objective sleep, and arousal in the pre-sleep state would mediate the relationship between depression status and fatigue. Sleep, pre-sleep arousal, and…

  5. Decentralized Planning for Pre-Conflict and Post-Conflict ...

    African Journals Online (AJOL)

    2012-10-02

    Oct 2, 2012 ... Such processes are 'sine qua non' to pre-conflict and post-conflict prevention. .... A Basic Approach to Pre-Conflict Management Planning ... and also factor in an evaluation of perception variables that help us to understand ...

  6. Pre-Employment Course: A Partnership for Success?

    Science.gov (United States)

    Pepper, Ian K.; McGrath, Ruth

    2010-01-01

    Purpose: The purpose of this paper is to examine the benefits of pre-employment education and training and its impact on the students' choice of career paths. It focuses on a programme delivered in partnership between Teesside University and a North East Police Force, and provides a model for future pre-employment education and training.…

  7. Pre-Service Teachers Designing and Constructing "Good Digital Games"

    Science.gov (United States)

    Artym, Corbett; Carbonaro, Mike; Boechler, Patricia

    2016-01-01

    There is a growing interest in the application of digital games to enhance learning across many educational levels. This paper investigates pre-service teachers' ability to operationalize the learning principles that are considered part of a good digital game (Gee, 2007) by designing digital games in Scratch. Forty pre-service teachers, enrolled…

  8. Pre-Service Teachers Designing Virtual World Learning Environments

    Science.gov (United States)

    Jacka, Lisa; Booth, Kate

    2012-01-01

    Integrating Information Technology Communications in the classroom has been an important part of pre-service teacher education for over a decade. The advent of virtual worlds provides the pre-service teacher with an opportunity to study teaching and learning in a highly immersive 3D computer-based environment. Virtual worlds also provide a place…

  9. Cognitive function after pre-eclampsia: an explorative study.

    NARCIS (Netherlands)

    Baecke, M.; Spaanderman, M.E.A.; Werf, S.P. van der

    2009-01-01

    BACKGROUND: Pre-eclampsia and eclampsia relate to cerebral damage. Memory and concentration problems are frequently reported after these pregnancy-related vascular complications. We tested the hypothesis that in formerly pre-eclamptic women cognitive functioning is impaired as compared with healthy

  10. 24 CFR 203.370 - Pre-foreclosure sales.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Pre-foreclosure sales. 203.370...-foreclosure sales. (a) General. HUD will pay FHA insurance benefits to mortgagees in cases where, in accordance with all regulations and procedures applicable to pre-foreclosure sales, the mortgaged property is...

  11. Pre-service teachers' content knowledge and pedagogical content ...

    African Journals Online (AJOL)

    This study investigated pre-service teachers' content and pedagogical knowledge in teaching geometric transformation. Eighty-two pre-service teachers from two Colleges of Education in the Ashanti region of Ghana consisted the sample size. The study was a quantitative study which employed survey as a strategy of ...

  12. 28 CFR 345.81 - Pre-industrial training.

    Science.gov (United States)

    2010-07-01

    ... training is available and the worker has not completed both the skill training and orientation phases of... pre-industrial training is not available, new FPI assignees will receive on-the-job training in pre-industrial pay status for a period of at least 30 days before being promoted into available fourth grade jobs. ...

  13. FLAT FEET OF DHE CHILDREN IN PRE-SCHOOL AGE

    Directory of Open Access Journals (Sweden)

    Admira Koničanin

    2011-03-01

    Full Text Available Subjekt : Of this research are flat feet of the children of both sexes in pre-school age children Aim : Of the research is confirm wheter is exists or flat feel of the children of both sexes in pre-school age.

  14. Atopic dermatitis-like pre-Sézary syndrome

    DEFF Research Database (Denmark)

    Sokolowska-Wojdylo, Malgorzata; Baranska-Rybak, Wioletta; Cegielska, Agnieszka

    2011-01-01

    histology without presence of atypical cells). In our patients, overt Sézary syndrome developed after immunosuppressive treatment (including cyclosporine). These cases support the validity of the concept of pre-Sézary syndrome, which is a long-lasting, pre-malignant condition, and which may develop to true...

  15. Pre-Service Teachers and Climate Change: A Stalemate?

    Science.gov (United States)

    Boon, Helen J.

    2016-01-01

    Findings from the second phase of a study of pre-service teachers' attitudes to environmental education and knowledge of climate change are reported in this paper. A sample of 87 pre-service teachers participated in a survey study in the last year of their Bachelor of Education degree to examine developments to their attitudes to environmental…

  16. Changing Pre-Service Elementary Teachers' Beliefs about Mathematical Knowledge

    Science.gov (United States)

    Stohlmann, Micah; Moore, Tamara; Cramer, Kathleen; Maiorca, Cathrine

    2015-01-01

    Studies have reported that pre-service teachers often enter teacher preparation programs with beliefs and attitudes not conducive to teaching the subject conceptually. In the USA, the Common Core State Standards for Mathematics have brought a renewed focus on procedural and conceptual understanding. However, many U.S. pre-service teachers have…

  17. Isotope heterogeneity of Pre-Holocene groundwater in Iceland

    DEFF Research Database (Denmark)

    Sveinbjörnsdóttir, Á.E.; Arnorsson, S.; Heinemeier, Jan

    2007-01-01

    In recent years, it has been shown that groundwater with a Pre-Holocene component is more common in the Icelandic bedrock than previously thought. Some of the Pre-Holocene water samples are more depleted in delta H-2 and delta O-18 than any mean annual precipitation in Iceland today due to the cold...... climate at that time. However, most often Pre-Holocene water components cannot be detected based on the water isotopes alone due to mixing with younger and isotopically heavier water. The Cl concentration in relation to the water isotopes in specific areas has proved to be a good indicator of a Pre......-Holocene component in the groundwater. The deuterium excess value may also help to identify water from a different climate regime, if no oxygen shift has occurred. The relative abundance of a Pre-Holocene water component of the Icelandic groundwater has led to the understanding that combined interpretation of water...

  18. Combined Screening for Early Detection of Pre-Eclampsia

    Directory of Open Access Journals (Sweden)

    Hee Jin Park

    2015-08-01

    Full Text Available Although the precise pathophysiology of pre-eclampsia remains unknown, this condition continues to be a major cause of maternal and fetal mortality. Early prediction of pre-eclampsia would allow for timely initiation of preventive therapy. A combination of biophysical and biochemical markers are superior to other tests for early prediction of the development of pre-eclampsia. Apart from the use of parameters in first-trimester aneuploidy screening, cell-free fetal DNA quantification is emerging as a promising marker for prediction of pre-eclampsia. This article reviews the current research of the most important strategies for prediction of pre-eclampsia, including the use of maternal risk factors, mean maternal arterial pressure, ultrasound parameters, and biomarkers.

  19. Gene expression profiling of placentas affected by pre-eclampsia

    DEFF Research Database (Denmark)

    Hoegh, Anne Mette; Borup, Rehannah; Nielsen, Finn Cilius

    2010-01-01

    Several studies point to the placenta as the primary cause of pre-eclampsia. Our objective was to identify placental genes that may contribute to the development of pre-eclampsia. RNA was purified from tissue biopsies from eleven pre-eclamptic placentas and eighteen normal controls. Messenger RNA...... expression from pooled samples was analysed by microarrays. Verification of the expression of selected genes was performed using real-time PCR. A surprisingly low number of genes (21 out of 15,000) were identified as differentially expressed. Among these were genes not previously associated with pre-eclampsia...... as bradykinin B1 receptor and a 14-3-3 protein, but also genes that have already been connected with pre-eclampsia, for example, inhibin beta A subunit and leptin. A low number of genes were repeatedly identified as differentially expressed, because they may represent the endpoint of a cascade of events...

  20. Bootstrapping pre-averaged realized volatility under market microstructure noise

    DEFF Research Database (Denmark)

    Hounyo, Ulrich; Goncalves, Sílvia; Meddahi, Nour

    The main contribution of this paper is to propose a bootstrap method for inference on integrated volatility based on the pre-averaging approach of Jacod et al. (2009), where the pre-averaging is done over all possible overlapping blocks of consecutive observations. The overlapping nature of the pre......-averaged returns implies that these are kn-dependent with kn growing slowly with the sample size n. This motivates the application of a blockwise bootstrap method. We show that the "blocks of blocks" bootstrap method suggested by Politis and Romano (1992) (and further studied by Bühlmann and Künsch (1995......)) is valid only when volatility is constant. The failure of the blocks of blocks bootstrap is due to the heterogeneity of the squared pre-averaged returns when volatility is stochastic. To preserve both the dependence and the heterogeneity of squared pre-averaged returns, we propose a novel procedure...

  1. Day care for pre-school children.

    Science.gov (United States)

    Zoritch, B; Roberts, I; Oakley, A

    2000-01-01

    The debate about how, where and by whom young children should be looked after is one which has occupied much social policy and media attention in recent years. Mothers undertake most of the care of young children. Internationally, out-of-home day-care provision ranges widely. These different levels of provision are not simply a response to different levels of demand for day-care, but reflect cultural and economic interests concerning the welfare of children, the need to promote mothers' participation in paid work, and the importance of socialising children into society's values. At a time when a decline in family values is held responsible for a range of social problems, the day-care debate has a special prominence. To quantify the effects of out-of-home day-care for preschool children on educational, health and welfare outcomes for children and their families. Randomised controlled trials of day-care for pre-school children were identified using electronic databases, hand searches of relevant literature, and contact with authors. Studies were included in the review if the intervention involved the provision of non-parental day care for children under 5 years of age, and the evaluation design was that of a randomised or quasi-randomised controlled trial. A total of eight trials were identified after examining 920 abstracts and 19 books. The trials were assessed for methodological quality. Day-care increases children's IQ, and has beneficial effects on behavioural development and school achievement. Long-term follow up demonstrates increased employment, lower teenage pregnancy rates, higher socio-economic status and decreased criminal behaviour. There are positive effects on mothers' education, employment and interaction with children. Effects on fathers have not been examined. Few studies look at a range of outcomes spanning the health, education and welfare domains. Most of the trials combined non-parental day-care with some element of parent training or education

  2. Pre-exposure prophylaxis of HIV

    Science.gov (United States)

    Naswa, Smriti; Marfatia, Y. S.

    2011-01-01

    Pre-exposure prophylaxis (PrEP) is an experimental approach to HIV prevention and consists of antiretroviral drugs to be taken before potential HIV exposure in order to reduce the risk of HIV infection and continued during periods of risk. An effective PrEP could provide an additional safety net to sexually active persons at risk, when combined with other prevention strategies. Women represent nearly 60% of adults infected with HIV and PrEP can be a female-controlled prevention method for women who are unable to negotiate condom use. Two antiretroviral nucleoside analog HIV-1 reverse transcriptase inhibitor drugs are currently under trial as PrEP drugs, namely tenofovirdisoproxilfumarate (TDF) alone and TDF in combination with emricitabine (FTC), to be taken as daily single dose oral drugs. There are 11 ongoing trials of ARV-based prevention in different at risk populations across the world. The iPrex trial showed that daily use of oral TDF/FTC by MSM resulted in 44% reduction in the incidence of HIV. This led to publication of interim guidance by CDC to use of PrEP by health providers for MSM. Few other trials are Bangkok Tenofovir Study, Partners PrEP Study, FEM-PrEP study, and VOICE (MTN-003) study. Future trials are being formulated for intermittent PrEP (iPrEP) where drugs are taken before and after sex, “stand-in dose” iPrEP, vaginal or rectal PrEP, etc. There are various issues/concerns with PrEP such as ADRs and resistance to TDF/FTC, adherence to drugs, acceptability, sexual disinhibition, use of PrEP as first line of defense for HIV without other prevention strategies, and cost. The PrEP has a potential to address unmet need in public health if delivered as a part of comprehensive toolkit of prevention services, including risk-reduction, correct and consistent use of condoms, and diagnosis and treatment of sexually transmitted infections. PMID:21799568

  3. Serum 8-isoprostane increased in pre-eclampsia

    Directory of Open Access Journals (Sweden)

    Besari Adi Pramono

    2012-04-01

    Full Text Available Background The main causes of maternal mortality in Indonesia are pre-eclampsia, hemorrhage, and infection. Oxidative stress has a primary role in pre-eclampsia and one of its parameters is 8-isoprostane serum level. The objective of this study is to measure 8-isoprostane and to analyze the relationship between 8-isoprostane level and birth weight in pre-eclampsia. Methods A cross-sectional study involving 23 pre-eclampsia and 29 normotensive pregnant women with normal or cesarean delivery at Dr. Kariadi Hospital Semarang from January to May 2011. Collected maternal blood samples were assessed for 8-Isoprostane levels by means of a specific ELISA kit. Neonatal birth weight was measured immediately after delivery by means of calibrated baby scales. Differences in 8-isoprostane levels between pre-eclampsia and normotensive women were assessed using independent t-test for normal distributed data, and the Mann-Whitney test for non-normally distributed data. Results Mean 8-isoprostane level was significantly higher in women with pre-eclampsia than in normotensive women (62.52 ± 12.19 pg/mL vs 28.64 ± 8.81 pg/mL (p<0.05. Low birth weight was twice as frequent in pre-eclampsia than in normotensives. There was no correlation between 8-isoprostane serum level and neonatal birth weight in pre-eclampsia. Conclusion The level of 8-isoprostane was higher in pre-eclampsia than in normotensives. It is recommended to conduct further studies to determine whether 8-isoprostane may be used as a predictive marker of pre-eclampsia.

  4. Cloning and characterization of pre-miR159a and pre-miR1123 from ...

    African Journals Online (AJOL)

    Although many miRNA genes are conserved across the plant species, the same gene family varies significantly in size and genomic organization in different species. ... Sequence identity matrix suggests 43-82% variation in precursor of Tae AL pre-miR159a (Tae Agra local pre-miR159a) across the species. On the other ...

  5. Prevalence of pre-diabetes, diabetes, pre-hypertension, and hypertension in children weighing more than normal

    Directory of Open Access Journals (Sweden)

    Priti Phatale

    2012-01-01

    Full Text Available Aim: Prevalence of pre-diabetes, diabetes, pre-hypertension (pre-HT, and hypertension (HT in children weighing more than normal. Materials and Methods: Three- to eighteen-year old children weighing more than normal were included. Pathological short children were excluded. According to Centre for Disease Control (CDC, children are grouped into overweight (OW and obese (OB. Indian B.P. reference tables are used for defining HT and pre-HT. [2] HbA1c by HPLC (BIO RAD method was used to define pre-diabetes and diabetes. [3] Children with HbA1c ≥6.5 were subjected for Glucose Tolerance Test (GTT. C-peptide assay was done to rule out (r/o IDDM. Observations: When we compare this with our earlier presentation at PEDICON 2011, we found that hypertension (HTN (22.9% vs. 23.07% is not significantly different but pre-HTN (28.09% vs. 33.9%, pre-diabetes mellitus (pre-DM (3.7% vs. 64.3%, and diabetes mellitus (DM (0.35% vs. 3.8% are significantly high in this study. Conclusion: (1 Prevalence of HT (22.90% vs. 23.07% is similar in both groups but pre-HT (33.9% vs. 28.09% is high in this study. (2 Significant rise in prevalence of diabetes (3.84% vs. 0.35% and pre-diabetes (64.33% vs. 3.7% is seen in this study. (3 This change is because of using HbA1c as screening tool in children weighing more than normal.

  6. Symbolic Analysis of the Cycle-to-Cycle Variability of a Gasoline–Hydrogen Fueled Spark Engine Model

    Directory of Open Access Journals (Sweden)

    Israel Reyes-Ramírez

    2018-04-01

    Full Text Available An study of temporal organization of the cycle-to-cycle variability (CCV in spark ignition engines fueled with gasoline–hydrogen blends is presented. First, long time series are generated by means of a quasi-dimensional model incorporating the key chemical and physical components, leading to variability in the time evolution of energetic functions. The alterations in the combustion process, for instance the composition of reactants, may lead to quantitative changes in the time evolution of the main engine variables. It has been observed that the presence of hydrogen in the fuel mixture leads to an increased laminar flame speed, with a corresponding decrease in CCV dispersion. Here, the effects of different hydrogen concentrations in the fuel are considered. First, it is observed that return maps of heat release sequences exhibit different patterns for different hydrogen concentrations and fuel–air ratios. Second, a symbolic analysis is used to characterize time series. The symbolic method is based on the probability of occurrence of consecutive states (a word in a symbolic sequence histogram (SSH. Modified Shannon entropy is computed in order to determine the adequate word length. Results reveal the presence of non-random patterns in the sequences and soft transitions between states. Moreover, the general behavior of CCV simulations results and three types of synthetic noises: white, log-normal, and a noisy logistic map, are compared. This analysis reveals that the non-random features observed in heat release sequences are quite different from synthetic noises.

  7. Direct-hydrogen-fueled proton-exchange-membrane fuel cell system for transportation applications. Hydrogen vehicle safety report

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, C.E. [Directed Technologies, Inc., Arlington, VA (United States)

    1997-05-01

    This report reviews the safety characteristics of hydrogen as an energy carrier for a fuel cell vehicle (FCV), with emphasis on high pressure gaseous hydrogen onboard storage. The authors consider normal operation of the vehicle in addition to refueling, collisions, operation in tunnels, and storage in garages. They identify the most likely risks and failure modes leading to hazardous conditions, and provide potential countermeasures in the vehicle design to prevent or substantially reduce the consequences of each plausible failure mode. They then compare the risks of hydrogen with those of more common motor vehicle fuels including gasoline, propane, and natural gas.

  8. Contribution to the modelling of reversible electrolyser and hydrogen fuel cell for coupling to the photovoltaic generators

    International Nuclear Information System (INIS)

    Rabih, S.

    2008-10-01

    A response to concerns raised by an energy mix which mainly consists of exhaustible fossil fuels harmful to the environment is to gradually substitute them by renewable energy sources, including solar or wind power. However, these intermittent flow energies set a recovery problem. They are often the source of electricity which inherits their fluctuations, which requires a transport network and which is an energy carrier not easy to store. In this context hydrogen synthesized from this renewable electricity, storing, it is considered as a stock carrier promising for the future. Various components and electrochemical processes are associated with this perspective: electrolysers, fuel cells, associations of these two functions combined in the system or integrated into a unitised reversible component. Our work is set in this perspective. It contributed to the development of advanced models of electrochemical components of electrolyser or fuel cells type, integrating reversibility for the study of their coupling to the photovoltaic generators. The models developed following a unified energetic approach use bond graph representation. After an analysis of the energy context, a state of the art of electrochemical components coupling hydrogen and electricity is presented, particularly on electrolysers and regenerative or unitised reversible fuel cells. Then, after a reminder of the principles of the Bond Graph representation, we exploit this formalism to develop an energetic model of a reversible component 'electrolyser and / or fuel cell' representative at macroscopic level of conversion reaction and dissipation phenomena, coupled in chemical, thermodynamic, electrical, thermal and fluid fields. Tests for characterization and validation conducted on small experimental devices are then described. They can illustrate the influence of operating parameters on the performance of these components. Finally, the Bond Graph model is used to study the modularity of components, including electrical and thermal imbalances in series or parallel associations of fuel cells or electrolysers. An architecture combining these elements with a photovoltaic generator to power an electric load or an electrical grid is finally submitted. (author)

  9. Optimized design and control of an off grid solar PV/hydrogen fuel cell power system for green buildings

    Science.gov (United States)

    Ghenai, C.; Bettayeb, M.

    2017-11-01

    Modelling, simulation, optimization and control strategies are used in this study to design a stand-alone solar PV/Fuel Cell/Battery/Generator hybrid power system to serve the electrical load of a commercial building. The main objective is to design an off grid energy system to meet the desired electric load of the commercial building with high renewable fraction, low emissions and low cost of energy. The goal is to manage the energy consumption of the building, reduce the associate cost and to switch from grid-tied fossil fuel power system to an off grid renewable and cleaner power system. Energy audit was performed in this study to determine the energy consumption of the building. Hourly simulations, modelling and optimization were performed to determine the performance and cost of the hybrid power configurations using different control strategies. The results show that the hybrid off grid solar PV/Fuel Cell/Generator/Battery/Inverter power system offers the best performance for the tested system architectures. From the total energy generated from the off grid hybrid power system, 73% is produced from the solar PV, 24% from the fuel cell and 3% from the backup Diesel generator. The produced power is used to meet all the AC load of the building without power shortage (system produces 18.2% excess power that can be used to serve the thermal load of the building. The proposed hybrid power system is sustainable, economically viable and environmentally friendly: High renewable fraction (66.1%), low levelized cost of energy (92 /MWh), and low carbon dioxide emissions (24 kg CO2/MWh) are achieved.

  10. Thermal management optimization of an air-cooled hydrogen fuel cell system in an extreme environmental condition

    DEFF Research Database (Denmark)

    Gao, Xin; Olesen, Anders Christian; Kær, Søren Knudsen

    2018-01-01

    An air-cooled proton exchange membrane (PEM) fuel cell system is designed and under manufacture for telecommunication back-up power. To enhance its competence in various environments, the system thermal feature is optimized in this work via simulation based on a computational fluid dynamics (CFD......, the intake airflow magnitude, is also studied for a more uniform airflow and in turn a suppressed temperature disparity inside the system. Following the guidelines drawn by this work on the system design and the operation setting, the air-cooled fuel cell system can be expected with better performances......) model. The model is three-dimensional (3D) and built in the commercial CFD package Fluent (ANSYS Inc.). It makes the full-scale system-level study feasible by only considering the system essences with adequate accuracy. Through the model, the optimization is attained in several aspects. Firstly...

  11. A study of diesel-hydrogen fuel exhaust emissions in a compression ignition engine/generator assembly

    International Nuclear Information System (INIS)

    Karri, V.; Hafez, H.A.; Kirkegaard, J.F.

    2006-01-01

    A compression engine and duel-fuel supply system was studied in order to determine the influence of hydrogen gas on a diesel engine's exhaust system. Commercially available solenoid valves and pulse actuators were used in a customized mechatronic control unit (MICU) to inject the hydrogen gas into the cylinders during the experiments. The MICU was designed as a generic external attachment. Diesel fuel was used to ignite the hydrogen gas-air mixture after compression. Various different electrical loads were then applied using an alternator in order to stimulate the engine governor and control diesel flow. Results of the study showed that measured carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxide (NO x ) loads of exhaust emissions increased, while emissions of carbon dioxide (CO 2 ) decreased. Results also showed that higher temperatures and levels of NO x occurred when hydrogen was mixed with the induced air. It was concluded that higher levels of hydrogen may be needed to reduce emissions. 17 refs., 5 tabs., 2 figs

  12. Wavelet analysis of cyclic variability in a spark ignition engine powered by gasoline-hydrogen fuel blends

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Asok K. [Richard G. Lugar Centre for Renewable Energy, and Department of Mathematical Sciences, Indiana University, (United States)], email: asen@iupui.edu; Akif Ceviz, M.; Volkan Oner, I. [Department of Mechanical Engineering, University of Ataturk (Turkey)], email: aceviz@atauni.edu.tr

    2011-07-01

    The cycle-to-cycle variations (CCV) of the indicated mean effective pressure (IMEP) in a spark ignition engine fuelled by gasoline and gasoline-hydrogen blends is investigated. CCVs are estimated by using the coefficient of variation (COV) and the overall spectral power given by the global wavelet spectrum (GWS). It was found that the addition of hydrogen reduces the CCV of the IMEP. Analysis of the wavelet can also identify the dominant modes of variability and delineate the engine cycles over which these modes can persist. Air-fuel ratio was varied from 1.0 to 1.3, and hydrogen was added up to 7.74% by volume. The engine was operated at 2000 rpm. Results demonstrate that subject to air-fuel ratio and % of hydrogen added, IMEP time series can exhibit multiscale dynamics consisting of persistent oscillations and intermittent fluctuations. These results can help develop effective control strategies to reduce cyclic variability in a spark ignition engine fuelled by gasoline-hydrogen mixtures.

  13. Operating Point Optimization of a Hydrogen Fueled Hybrid Solid Oxide Fuel Cell-Steam Turbine (SOFC-ST Plant

    Directory of Open Access Journals (Sweden)

    Juanjo Ugartemendia

    2013-09-01

    Full Text Available This paper presents a hydrogen powered hybrid solid oxide fuel cell-steam turbine (SOFC-ST system and studies its optimal operating conditions. This type of installation can be very appropriate to complement the intermittent generation of renewable energies, such as wind generation. A dynamic model of an alternative hybrid SOFC-ST configuration that is especially suited to work with hydrogen is developed. The proposed system recuperates the waste heat of the high temperature fuel cell, to feed a bottoming cycle (BC based on a steam turbine (ST. In order to optimize the behavior and performance of the system, a two-level control structure is proposed. Two controllers have been implemented for the stack temperature and fuel utilization factor. An upper supervisor generates optimal set-points in order to reach a maximal hydrogen efficiency. The simulation results obtained show that the proposed system allows one to reach high efficiencies at rated power levels.

  14. A survey of processes for producing hydrogen fuel from different sources for automotive-propulsion fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Brown, L.F.

    1996-03-01

    Seven common fuels are compared for their utility as hydrogen sources for proton-exchange-membrane fuel cells used in automotive propulsion. Methanol, natural gas, gasoline, diesel fuel, aviation jet fuel, ethanol, and hydrogen are the fuels considered. Except for the steam reforming of methanol and using pure hydrogen, all processes for generating hydrogen from these fuels require temperatures over 1000 K at some point. With the same two exceptions, all processes require water-gas shift reactors of significant size. All processes require low-sulfur or zero-sulfur fuels, and this may add cost to some of them. Fuels produced by steam reforming contain {approximately}70-80% hydrogen, those by partial oxidation {approximately}35-45%. The lower percentages may adversely affect cell performance. Theoretical input energies do not differ markedly among the various processes for generating hydrogen from organic-chemical fuels. Pure hydrogen has severe distribution and storage problems. As a result, the steam reforming of methanol is the leading candidate process for on-board generation of hydrogen for automotive propulsion. If methanol unavailability or a high price demands an alternative process, steam reforming appears preferable to partial oxidation for this purpose.

  15. Production and purification of a soluble hydrogenase from Ralstonia eutropha H16 for potential hydrogen fuel cell applications.

    Science.gov (United States)

    Jugder, Bat-Erdene; Lebhar, Helene; Aguey-Zinsou, Kondo-Francois; Marquis, Christopher P

    2016-01-01

    The soluble hydrogenase (SH) from Ralstonia eutropha H16 is a promising candidate enzyme for H2-based biofuel application as it favours H2 oxidation and is relatively oxygen-tolerant. In this report, bioprocess development studies undertaken to produce and purify an active SH are described, based on the methods previously reported [1], [2], [3], [4]. Our modifications are: •Upstream method optimizations were undertaken on heterotrophic growth media and cell lysis involving ultrasonication.•Two anion exchangers (Q Sepharose and RESOURCE Q) and size exclusion chromatographic (Superdex 200) matrices were successfully employed for purification of a hexameric SH from R. eutropha.•The H2 oxidizing activity of the SH was demonstrated spectrophotometrically in solution and also immobilized on an EPG electrode using cyclic voltammetry.

  16. Delayed hydride cracking: alternative pre-cracking method

    International Nuclear Information System (INIS)

    Mieza, Juan I.; Ponzoni, Lucio M.E.; Vigna, Gustavo L.; Domizzi, Gladys

    2009-01-01

    The internal components of nuclear reactors built-in Zr alloys are prone to a failure mechanism known as Delayed Hydride Cracking (DHC). This situation has triggered numerous scientific studies in order to measure the crack propagation velocity and the threshold stress intensity factor associated to DHC. Tests are carried out on fatigued pre-crack samples to ensure similar test conditions and comparable results. Due to difficulties in implementing the fatigue pre-crack method it would be desirable to replace it with a pre-crack produced by the same process of DHC, for which is necessary to demonstrate equivalence of this two methods. In this work tests on samples extracted from two Zr-2.5 Nb tubes were conducted. Some of the samples were heat treated to obtain a range in their metallurgical properties as well as different DHC velocities. A comparison between velocities measured in test samples pre-cracked by fatigue and RDIH is done, demonstrating that the pre-cracking method does not affect the measured velocity value. In addition, the incubation (t inc ), which is the time between the application of the load and the first signal of crack propagation, in samples pre-cracked by RDIH, was measured. It was found that these times are sufficiently short, even in the worst cases (lower speed) and similar to the ones of fatigued pre-cracked samples. (author)

  17. Pre-glow phenomenon origin and its scaling for ECRIS

    International Nuclear Information System (INIS)

    Izotov, I.; Sidorov, A.; Skalyga, V.; Zorin, V.

    2012-01-01

    Pre-glow is the multi-charged ion current burst that may occur at the beginning of the beam pulse. Pre-glow effect investigation is one of topical directions of ECR ion sources development at present. Pre-glow is of interest for efficient short-pulsed multicharged ion source creation. Particularly, such source of intense beams of short living radioactive isotopes multi-charged ions is one of key elements in 'Beta-Beam' European project. The use of Pre-glow-generating regime of an ECRIS operation is a promising way of pulsed high-intense multi-charged ion beams production with much shorter edges in comparison with usual operation regime. Numerical simulations made with the updated theoretical model allow authors to propose more physical and intuitive explanations of Pre-glow phenomenon origins. The obtained dependences of Pre-glow characteristics on experimental conditions offer a scaling for a wide range of ECRIS. The propose scaling demonstrates that an ECR source with plasma heating by radiation at frequency of 37 GHz and higher seems to be the most effective in terms of currents, pre-glow intensity and mean ion charge. The paper is followed by the slides of the presentation

  18. Monitoring Pre-Stressed Composites Using Optical Fibre Sensors.

    Science.gov (United States)

    Krishnamurthy, Sriram; Badcock, Rodney A; Machavaram, Venkata R; Fernando, Gerard F

    2016-05-28

    Residual stresses in fibre reinforced composites can give rise to a number of undesired effects such as loss of dimensional stability and premature fracture. Hence, there is significant merit in developing processing techniques to mitigate the development of residual stresses. However, tracking and quantifying the development of these fabrication-induced stresses in real-time using conventional non-destructive techniques is not straightforward. This article reports on the design and evaluation of a technique for manufacturing pre-stressed composite panels from unidirectional E-glass/epoxy prepregs. Here, the magnitude of the applied pre-stress was monitored using an integrated load-cell. The pre-stressing rig was based on a flat-bed design which enabled autoclave-based processing. A method was developed to end-tab the laminated prepregs prior to pre-stressing. The development of process-induced residual strain was monitored in-situ using embedded optical fibre sensors. Surface-mounted electrical resistance strain gauges were used to measure the strain when the composite was unloaded from the pre-stressing rig at room temperature. Four pre-stress levels were applied prior to processing the laminated preforms in an autoclave. The results showed that the application of a pre-stress of 108 MPa to a unidirectional [0]16 E-glass/913 epoxy preform, reduced the residual strain in the composite from -600 µε (conventional processing without pre-stress) to approximately zero. A good correlation was observed between the data obtained from the surface-mounted electrical resistance strain gauge and the embedded optical fibre sensors. In addition to "neutralising" the residual stresses, superior axial orientation of the reinforcement can be obtained from pre-stressed composites. A subsequent publication will highlight the consequences of pres-stressing on fibre alignment, the tensile, flexural, compressive and fatigue performance of unidirectional E-glass composites.

  19. Monitoring Pre-Stressed Composites Using Optical Fibre Sensors

    Directory of Open Access Journals (Sweden)

    Sriram Krishnamurthy

    2016-05-01

    Full Text Available Residual stresses in fibre reinforced composites can give rise to a number of undesired effects such as loss of dimensional stability and premature fracture. Hence, there is significant merit in developing processing techniques to mitigate the development of residual stresses. However, tracking and quantifying the development of these fabrication-induced stresses in real-time using conventional non-destructive techniques is not straightforward. This article reports on the design and evaluation of a technique for manufacturing pre-stressed composite panels from unidirectional E-glass/epoxy prepregs. Here, the magnitude of the applied pre-stress was monitored using an integrated load-cell. The pre-stressing rig was based on a flat-bed design which enabled autoclave-based processing. A method was developed to end-tab the laminated prepregs prior to pre-stressing. The development of process-induced residual strain was monitored in-situ using embedded optical fibre sensors. Surface-mounted electrical resistance strain gauges were used to measure the strain when the composite was unloaded from the pre-stressing rig at room temperature. Four pre-stress levels were applied prior to processing the laminated preforms in an autoclave. The results showed that the application of a pre-stress of 108 MPa to a unidirectional [0]16 E-glass/913 epoxy preform, reduced the residual strain in the composite from −600 µε (conventional processing without pre-stress to approximately zero. A good correlation was observed between the data obtained from the surface-mounted electrical resistance strain gauge and the embedded optical fibre sensors. In addition to “neutralising” the residual stresses, superior axial orientation of the reinforcement can be obtained from pre-stressed composites. A subsequent publication will highlight the consequences of pres-stressing on fibre alignment, the tensile, flexural, compressive and fatigue performance of unidirectional E

  20. Monitoring Pre-Stressed Composites Using Optical Fibre Sensors

    Science.gov (United States)

    Krishnamurthy, Sriram; Badcock, Rodney A.; Machavaram, Venkata R.; Fernando, Gerard F.

    2016-01-01

    Residual stresses in fibre reinforced composites can give rise to a number of undesired effects such as loss of dimensional stability and premature fracture. Hence, there is significant merit in developing processing techniques to mitigate the development of residual stresses. However, tracking and quantifying the development of these fabrication-induced stresses in real-time using conventional non-destructive techniques is not straightforward. This article reports on the design and evaluation of a technique for manufacturing pre-stressed composite panels from unidirectional E-glass/epoxy prepregs. Here, the magnitude of the applied pre-stress was monitored using an integrated load-cell. The pre-stressing rig was based on a flat-bed design which enabled autoclave-based processing. A method was developed to end-tab the laminated prepregs prior to pre-stressing. The development of process-induced residual strain was monitored in-situ using embedded optical fibre sensors. Surface-mounted electrical resistance strain gauges were used to measure the strain when the composite was unloaded from the pre-stressing rig at room temperature. Four pre-stress levels were applied prior to processing the laminated preforms in an autoclave. The results showed that the application of a pre-stress of 108 MPa to a unidirectional [0]16 E-glass/913 epoxy preform, reduced the residual strain in the composite from −600 µε (conventional processing without pre-stress) to approximately zero. A good correlation was observed between the data obtained from the surface-mounted electrical resistance strain gauge and the embedded optical fibre sensors. In addition to “neutralising” the residual stresses, superior axial orientation of the reinforcement can be obtained from pre-stressed composites. A subsequent publication will highlight the consequences of pres-stressing on fibre alignment, the tensile, flexural, compressive and fatigue performance of unidirectional E-glass composites. PMID

  1. Pre-operative pain and sensory function in groin hernia

    DEFF Research Database (Denmark)

    Aasvang, Eske K; Hansen, Jeanette B; Kehlet, Henrik

    2009-01-01

    BACKGROUND: Although persistent postherniotomy occurs in 5-10% of patients, pathogenic mechanisms remain debatable. Since pre-operative pain has been demonstrated to be a risk factor for persistent postherniotomy pain, pre-operative alterations in nociceptive function may be a potential pathogenic...... mechanism. AIMS: To investigate the correlation between pre-operative pain intensity and sensory functions in the groin hernia area. METHODS: Patients with unilateral groin hernia were examined preoperatively by quantitative sensory testing (thermal, mechanical, and pressure [detection and pain thresholds...... (7%), all whom experienced no pain or pain less than weekly. Only cool detection thresholds were significantly lower between the hernia vs. contralateral side (poperative groin hernia...

  2. Pre-calculus 1,001 practice problems for dummies

    CERN Document Server

    Sterling, Mary Jane; Sterling

    2014-01-01

    Prepare for calculus the smart way, with customizable pre-calculus practice 1,001 Pre-Calculus Practice Problems For Dummies offers 1,001 opportunities to gain confidence in your math skills. Much more than a workbook, this study aid provides pre-calculus problems ranked from easy to advanced, with detailed explanations and step-by-step solutions for each one. The companion website gives you free online access to all 1,001 practice problems and solutions, and you can track your progress and ID where you should focus your study time. Accessible on the go by smart phone, tablet, o

  3. Pre-migration Trauma Exposure and Psychological Distress for Asian American Immigrants: Linking the Pre- and Post-migration Contexts.

    Science.gov (United States)

    Li, Miao; Anderson, James G

    2016-08-01

    Drawing on the life course perspective and the assumptive world theory, this paper examines whether pre-migration trauma exposure is associated with psychological distress through post-migration perceived discrimination for Asian American immigrants. The study is based on cross-sectional data from the National Latino and Asian American Study (N = 1639). Structural equation model is used to estimate the relationship between pre-migration trauma, post-migration perceived discrimination, and psychological distress. Additional models are estimated to explore possible variations across ethnic groups as well as across different types of pre-migration trauma experience. Pre-migration trauma exposure is associated with higher levels of psychological distress, both directly and indirectly through higher level of perceived discrimination, even after controlling for demographic/acculturative factors and post-migration trauma exposure. This pattern holds for the following sub-types of pre-migration trauma: political trauma, crime victimization, physical violence, accidental trauma, and relational trauma. Multi-group analyses show that this pattern holds for all Asian immigrant subgroups except the Vietnamese. Studies of immigrant mental health primarily focus on post-migration stressors. Few studies have considered the link between pre- and post-migration contexts in assessing mental health outcomes. The study illustrates the usefulness of bridging the pre- and post-migration context in identifying the mental health risks along the immigrant life course.

  4. SHORT RESEARCH REPORTS The Aetiology and Agents of Pre ...

    African Journals Online (AJOL)

    Aetiology, agents, pre-hospital, transportation, femoral shafts, fractures. Introduction ... Disability often results from limb shortening, malalignment, and prolonged .... youngest patient was a day-old baby with a fracture resulting from birth trauma ...

  5. Pre-service secondary school science teachers science teaching ...

    African Journals Online (AJOL)

    PROF.MIREKU

    pre-service secondary science teachers' self-efficacy beliefs with regard to gender and educational .... outcome. As a consequence, instruments for the determination of self-efficacy ...... Sex Roles: A Journal of Research, 42, 119–31. Bursal, M.

  6. Pre-Schooling and Academic Performance of Lower Primary School ...

    African Journals Online (AJOL)

    The primary objective of this study was to investigate the relationship between pre- ... for increased public investment in Early Child Development (ECD) as a strategic ..... students' academic performance: A case study of Islamia University sub-.

  7. Evaluation of pre-service training on integrated management of ...

    African Journals Online (AJOL)

    Evaluation of pre-service training on integrated management of neonatal and childhood ... and reviews of pediatric course outlines and other teaching/learning materials. ... Of the 34 programs 22 were diploma nursing, 6 Bachelor of Sciences ...

  8. Pre-service teachers' content knowledge and pedagogical content ...

    African Journals Online (AJOL)

    kofi.mereku

    African Journal of Educational Studies in Mathematics and Sciences Vol. 13, 2017. 63 ... knowledge in teaching geometric transformation ... made more practical and that pre-service teachers should be given ample opportunity to practice.

  9. Pre-assembling electric circuits of braided conductors

    International Nuclear Information System (INIS)

    Mercado Gomez, Martin Elias

    1999-01-01

    The present article has for object to give to know an innovative concept of pre-assembling electric circuits for distribution of normal and regulated power, to the work position like integral subsystems of the calls intelligent buildings

  10. Exploring fraud triangle in understanding ethics pre-cautionary: a ...

    African Journals Online (AJOL)

    Exploring fraud triangle in understanding ethics pre-cautionary: a Malaysian ... Journal of Fundamental and Applied Sciences ... Various reports on the involvement of government officials in fraud cases indicate the lacking of ethical systems.

  11. 75 FR 45013 - Pre-Existing Condition Insurance Plan Program

    Science.gov (United States)

    2010-07-30

    ... Department of Homeland Security's U.S. Citizenship and Immigration Services (USCIS) Systematic Alien... pre-existing condition based on evidence of the existence or history of certain medical or health...

  12. Critical Challenges of Pre and Post Service Extension Education ...

    African Journals Online (AJOL)

    Critical Challenges of Pre and Post Service Extension Education and ... poor policy decision and implementation, rapid development in science and ... problems associated with information/communication echnologies access and utilization.

  13. The relevance of pre-motor symptoms in Parkinson's disease.

    Science.gov (United States)

    Visanji, Naomi; Marras, Connie

    2015-10-01

    Parkinson's disease (PD) has a wide range of non-motor symptoms including; constipation, sleep disturbance, deficits in vision and olfaction, mood disorders and cardiac autonomic dysfunction. Several of these non-motor symptoms can manifest prior to the onset of motor symptoms. Recognizing these pre-motor symptoms may enable early diagnosis of PD. Currently, no single pre-motor symptom is able to predict the development of PD with 100% sensitivity or specificity. Ongoing studies in several independent at-risk cohorts should reveal the potential of combinations of pre-motor symptoms and multi-stage screening strategies to identify individuals at increased risk of PD. PD progression may be governed by a prion-like spread of a-syn throughout the nervous system. Identifying individuals at the earliest stage will likely be critical to preventing the pathological progression of PD, highlighting the relevance of pre-motor symptoms in the future treatment of the disease.

  14. Engaging Youth and Pre-Service Teachers in Immigration Deliberations

    Science.gov (United States)

    Daniel, Shannon M.

    2015-01-01

    In this report of innovative teacher practice, the author describes an arts-based event which brought together adolescent refugee and immigrant students and pre-service teachers to deliberate about immigration policies and attitudes in the United States.

  15. Predictors of pre-game anxiety dysphoria among teenage soccer ...

    African Journals Online (AJOL)

    Predictors of pre-game anxiety dysphoria among teenage soccer players. ... The result confirmed a significant composite effect of the dependent variable on the independent variables (0.87637, 74.49548, ... AJOL African Journals Online.

  16. Assessment of pre-harvest aflatoxin and fumonisin contamination of ...

    African Journals Online (AJOL)

    Assessment of pre-harvest aflatoxin and fumonisin contamination of maize in Babati District, Tanzania. ... African Journal of Food, Agriculture, Nutrition and Development ... As well as participating in a development program, Africa Research in ...

  17. Pre-service teachers’ challenges in presenting mathematical problems

    Science.gov (United States)

    Desfitri, R.

    2018-01-01

    The purpose of this study was to analyzed how pre-service teachers prepare and assigned tasks or assignments in teaching practice situations. This study was also intended to discuss about kind of tasks or assignments they gave to students. Participants of this study were 15 selected pre-service mathematics teachers from mathematics education department who took part on microteaching class as part of teaching preparation program. Based on data obtained, it was occasionally found that there were hidden errors on questions or tasks assigned by pre-service teachers which might lead their students not to be able to reach a logical or correct answer. Although some answers might seem to be true, they were illogical or unfavourable. It is strongly recommended that pre-service teachers be more careful when posing mathematical problems so that students do not misunderstand the problems or the concepts, since both teachers and students were sometimes unaware of errors in problems being worked on.

  18. 10 CFR 609.5 - Evaluation of Pre-Applications.

    Science.gov (United States)

    2010-01-01

    ... Sponsor (including personal and/or business credit information of the principal(s)). (d) After the... other feedback that DOE may provide in response to the Pre-Application eliminates the requirement for an...

  19. Report on the Pre-existing Condition Insurance Plan Program

    Data.gov (United States)

    U.S. Department of Health & Human Services — Before the Affordable Care Act, Americans with pre-existing conditions who did not receive health coverage through their employers had few affordable options to get...

  20. Praten met kinderen: effectief voor ouders van (pre)adolescenten?

    NARCIS (Netherlands)

    Leijten, P.; Overbeek, G.; Janssens, J.

    2013-01-01

    This randomized controlled trial examined the effectiveness of the parent training programme: Parents and Children Talking Together (pctt) for parents with (pre)adolescent children who experience parenting difficulties. The programme focuses on reducing child problem behaviour by improving parents’