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Sample records for dedicated propane chrysler

  1. Emissions results for dedicated propane Chrysler minivans: the 1996 propane vehicle challenge

    SciTech Connect

    Buitrago, C.; Sluder, S.; Larsen, R.

    1997-02-01

    The U.S. Department of Energy (US DOE), through Argonne National Laboratory, and in cooperation with Natural Resources-Canada and Chrysler Canada, sponsored and organized the 1996 Propane Vehicle Challenge (PVC). For this competition , 13 university teams from North America each received a stock Chrysler minivan to be converted to dedicated propane operation while maintaining maximum production feasibility. The converted vehicles were tested for performance (driveability, cold- and hot-start, acceleration, range, and fuel economy) and exhaust emissions. Of the 13 entries for the 1996 PVC, 10 completed all of the events scheduled, including the emissions test. The schools used a variety of fuel-management, fuel-phase and engine-control strategies, but their strategies can be summarized as three main types: liquid fuel-injection, gaseous fuel-injection, and gaseous carburetor. The converted vehicles performed similarly to the gasoline minivan. The University of Windsor`s minivan had the lowest emissions attaining ULEV levels with a gaseous-injected engine. The Texas A&M vehicle, which had a gaseous-fuel injection system, and the GMI Engineering and Management Institute`s vehicle, which had a liquid-injection system both reached LEV levels. Vehicles with an injection fuel system (liquid or gaseous) performed better in terms of emissions than carbureted systems. Liquid injection appeared to be the best option for fuel metering and control for propane, but more research and calibration are necessary to improve the reliability and performance of this design.

  2. Hardware assembly and prototype testing for the development of a dedicated liquefied propane gas ultra low emission vehicle

    NASA Astrophysics Data System (ADS)

    1995-07-01

    On February 3, 1994, IMPCO Technologies, Inc. started the development of a dedicated LPG Ultra Low Emissions Vehicle (ULEV) under contract to the Midwest Research Institute National Renewable Energy Laboratory Division (NREL). The objective was to develop a dedicated propane vehicle that would meet or exceed the California ULEV emissions standards. The project is broken into four phases to be performed over a two year period. The four phases of the project include: (Phase 1) system design, (Phase 2) prototype hardware assembly and testing, (Phase 3) full-scale systems testing and integration, and (Phase 4) vehicle demonstration. This report describes the approach taken for the development of the vehicle and the work performed through the completion of Phase-2 dynamometer test results. Work was started on Phase 2 (Hardware Assembly and Prototype Testing) in May 1994 prior to completion of Phase 1 to ensure that long lead items would be available in a timely fashion for the Phase 2 work. In addition, the construction and testing of the interim electronic control module (ECM), which was used to test components, was begun prior to the formal start of Phase 2. This was done so that the shortened revised schedule for the project (24 months) could be met. In this report, a brief summary of the activities of each combined Phase 1 and 2 tasks will be presented, as well as project management activities. A technical review of the system is also given, along with test results and analysis. During the course of Phase 2 activities, IMPCO staff also had the opportunity to conduct cold start performance tests of the injectors. The additional test data was most positive and will be briefly summarized in this report.

  3. Hardware assembly and prototype testing for the development of a dedicated liquefied propane gas ultra low emission vehicle

    SciTech Connect

    1995-07-01

    On February 3, 1994, IMPCO Technologies, Inc. started the development of a dedicated LPG Ultra Low Emissions Vehicle (ULEV) under contract to the Midwest Research Institute National Renewable Energy Laboratory Division (NREL). The objective was to develop a dedicated propane vehicle that would meet or exceed the California ULEV emissions standards. The project is broken into four phases to be performed over a two year period. The four phases of the project include: (Phase 1) system design, (Phase 2) prototype hardware assembly and testing, (Phase 3) full-scale systems testing and integration, (Phase 4) vehicle demonstration. This report describes the approach taken for the development of the vehicle and the work performed through the completion of Phase II dynamometer test results. Work was started on Phase 2 (Hardware Assembly and Prototype Testing) in May 1994 prior to completion of Phase 1 to ensure that long lead items would be available in a timely fashion for the Phase 2 work. In addition, the construction and testing of the interim electronic control module (ECM), which was used to test components, was begun prior to the formal start of Phase 2. This was done so that the shortened revised schedule for the project (24 months) could be met. In this report, a brief summary of the activities of each combined Phase 1 and 2 tasks will be presented, as well as project management activities. A technical review of the system is also given, along with test results and analysis. During the course of Phase 2 activities, IMPCO staff also had the opportunity to conduct cold start performance tests of the injectors. The additional test data was most positive and will be briefly summarized in this report.

  4. 75 FR 34170 - Chrysler Group LLC, Formally Known as Chrysler LLC, Kenosha Engine Plant, Including On-Site...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-16

    ..., Wisconsin location of Chrysler Group LLC, formally known as Chrysler, LLC, Kenosha Engine Plant. The... location of Chrysler Group LLC, formally known as Chrysler, LLC, Kenosha Engine Plant. The amended notice... Employment and Training Administration Chrysler Group LLC, Formally Known as Chrysler LLC, Kenosha...

  5. Propane Basics

    SciTech Connect

    NREL

    2010-03-01

    Propane powers about 190,000 vehicles in the U.S. and more than 14 million worldwide. Propane vehicles are a good choice for many fleet applications including school buses, shuttle buses, taxies and light-duty trucks.

  6. Propane Update.

    ERIC Educational Resources Information Center

    Brantner, Max

    1984-01-01

    Reports on a northern Illinois school bus fleet converted to propane fuel in 1981 and 1982. Includes tables showing, first, total annual fuel costs before and after conversion and, second, fuel efficiency for 16 buses using propane and three using gasoline. Notes precautions for propane use. (MCG)

  7. The engine testing process at Chrysler

    SciTech Connect

    Jost, K.

    1996-03-01

    This article describes how the company`s 2.7-L V6 engine program for the 1998 LH will move from the first developmental engine to production in just over two years. Chrysler`s Large Car Platform team is developing a new 2.7-L V6 for the 1998 Dodge Intrepid/Chrysler Concorde (LH platform) successor. The four-valve-per-cylinder engine will replace the base overhead-valve, 3.3-L engine in the LH, and eventually the Mitsubishi-supplied six-cylinder in the Chrysler Cirrus/Dodge Stratus (JA platform). There were many reasons for development of the new LH engine: reduced NVH, improved reliability, and better performance. Other goals were 10% better vehicle fuel economy, so weight had to be shed by the powertrain, and new emission standards (LEV and ULEV) had to be met.

  8. 76 FR 13667 - Chrysler Group LLC; Formerly Known as Chrysler LLC; Kenosha Engine Plant; Including On-Site...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-14

    ... Employment and Training Administration Chrysler Group LLC; Formerly Known as Chrysler LLC; Kenosha Engine..., formerly known as Chrysler, LLC, Kenosha Engine Plant, Kenosha, Wisconsin (subject firm). The Department's... employment related to the production of V-6 automobile engines. At the request of the State agency,...

  9. 75 FR 76041 - Chrysler Group LLC Formerly Known as Chrysler LLC Kenosha Engine Plant Including On-Site Leased...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-07

    ... Employment and Training Administration Chrysler Group LLC Formerly Known as Chrysler LLC Kenosha Engine Plant... Engine Plant, Kenosha, Wisconsin (subject firm). The Department's notice of determination was published... employment related to the production of V-6 automobile engines. At the request of the State agency,...

  10. 75 FR 49535 - Lochmoor Chrysler Jeep; Detroit, MI; Notice of Negative Determination Regarding Application for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    ... Employment and Training Administration Lochmoor Chrysler Jeep; Detroit, MI; Notice of Negative Determination... administrative reconsideration of the Department's negative determination regarding eligibility to apply for... negative determination applicable to workers and former workers at Lochmoor Chrysler Jeep,...

  11. Chrysler Pentastar direct hydrogen fuel cell program

    SciTech Connect

    Kimble, M.; Deloney, D.

    1995-08-01

    The Chrysler Pentastar Electronics, Inc. Direct Hydrogen Fueled PEM Fuel Cell Hybrid Vehicle Program (DPHV) was initiated 1 July, 1994 with the following mission, {open_quotes}Design, fabricate, and test a Direct Hydrogen Fueled Proton Exchange Membrane (PEM) Fuel Cell System including onboard hydrogen storage, an efficient lightweight fuel cell, a gas management system, peak power augmentation and a complete system controls that can be economically mass produced and comply with all safety environmental and consumer requirements for vehicle applications for the 21st century.{close_quotes} The Conceptual Design for the entire system based upon the selection of an applicable vehicle and performance requirements that are consistent with the PNGV goals will be discussed. A Hydrogen Storage system that has been selected, packaged, and partially tested in accordance with perceived Hydrogen Safety and Infrastructure requirements will be discussed in addition to our Fuel Cell approach along with design of the {open_quotes}real{close_quotes} module. The Gas Management System and the Load Leveling System have been designed and the software programs have been developed and will be discussed along with a complete fuel cell test station that has the capability to test up to a 60 kW fuel cell system.

  12. 75 FR 21668 - Grant of Individual Exemption Involving Chrysler LLC, Located in Auburn Hills, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-26

    ... Chrysler Group LLC, and hereinafter referred to as ``New Chrysler''), a Delaware limited liability company... acquired certain core assets from Chrysler LLC in exchange for the assumption of certain liabilities of... contingent upon the success or size of an offering or sale, and (2) for each plan Account, the...

  13. Propane vehicles : status, challenges, and opportunities.

    SciTech Connect

    Rood Werpy, M.; Burnham, A.; Bertram, K.; Energy Systems

    2010-06-17

    Propane as an auto fuel has a high octane value and has key properties required for spark-ignited internal combustion engines. To operate a vehicle on propane as either a dedicated fuel or bi-fuel (i.e., switching between gasoline and propane) vehicle, only a few modifications must be made to the engine. Until recently propane vehicles have commonly used a vapor pressure system that was somewhat similar to a carburetion system, wherein the propane would be vaporized and mixed with combustion air in the intake plenum of the engine. This leads to lower efficiency as more air, rather than fuel, is inducted into the cylinder for combustion (Myers 2009). A newer liquid injection system has become available that injects propane directly into the cylinder, resulting in no mixing penalty because air is not diluted with the gaseous fuel in the intake manifold. Use of a direct propane injection system will improve engine efficiency (Gupta 2009). Other systems include the sequential multi-port fuel injection system and a bi-fuel 'hybrid' sequential propane injection system. Carbureted systems remain in use but mostly for non-road applications. In the United States a closed-loop system is used in after-market conversions. This system incorporates an electronic sensor that provides constant feedback to the fuel controller to allow it to measure precisely the proper air/fuel ratio. A complete conversion system includes a fuel controller, pressure regulator valves, fuel injectors, electronics, fuel tank, and software. A slight power loss is expected in conversion to a vapor pressure system, but power can still be optimized with vehicle modifications of such items as the air/fuel mixture and compression ratios. Cold start issues are eliminated for vapor pressure systems since the air/fuel mixture is gaseous. In light-duty propane vehicles, the fuel tank is typically mounted in the trunk; for medium- and heavy-duty vans and trucks, the tank is located under the body of the vehicle

  14. 39. VIEW OF CHRYSLER WORKERS LOADING A SATURN IB BOOSTER ...

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

    39. VIEW OF CHRYSLER WORKERS LOADING A SATURN IB BOOSTER INTO THE EAST POSITION ON THE STATIC TEST TOWER. AS THE MAIN CONTRACTOR OF THE SATURN IB BOOSTER, CHRYSLER TOOK OVER OPERATIONS OF THE EAST POSITION OF THE STATIC TEST TOWER IN 1963. THAT SAME YEAR, THE WEST POSITION OF THE TEST TOWER WAS MODIFIED (AS SEEN IN THE PHOTO) FOR RESEARCH AND DEVELOPMENT TESTS OF THE SATURN V BOOSTER'S ENGINE, THE F-1. MARCH 1963, MSFC PHOTO LAB. - Marshall Space Flight Center, Saturn Propulsion & Structural Test Facility, East Test Area, Huntsville, Madison County, AL

  15. Apologies and Public Relations Crises at Chrysler, Toshiba, and Volvo.

    ERIC Educational Resources Information Center

    Hearit, Keith Michael

    1994-01-01

    Analyzes the corporate apologetic discourses of three paradigmatic cases (at Chrysler, Toshiba, and Volvo) and examines the use of persuasive descriptions and strategic dissociations preferred by these corporate apologists. Shows how organizations label their wrongdoing in a way that displays sorrow but limits culpability and use dissociations to…

  16. 75 FR 21352 - Chrysler Group LLC, Formerly Known as Chrysler LLC; Belvidere Assembly Plant: Including On-Site...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-23

    ... Plant: Including On-Site Leased Workers From Aerotek, G Tech Services, Inc., and Tri-Dim Filer Corp... Plant, include on- site leased workers from Aerotek and G Tech Services, Inc., Belvidere, Illinois. The... known as Chrysler LLC, Belvidere Assembly Plant, including on-site leased workers from Aerotek, G...

  17. Performance characteristics of 1977 Chrysler 318 Cid engine. Final report

    SciTech Connect

    Boziuk, J.

    1980-02-01

    Experimental data were obtained in dynamometer tests of a 1977 Chrysler 318 CID engine to determine fuel consumption and emissions (hydrocarbons, carbon monoxide, and oxides of nitrogen) at steady-state engine operating modes. The objective of the test was to obtain engine performance data for estimating fuel consumption and emissions for varied engine service and duty and to provide basic engine characteristic data required for the TSC Vehicle Simulator (VEHSIM).

  18. Propane Vehicle Demonstration Grant Program

    SciTech Connect

    Jack Mallinger

    2004-08-27

    Project Description: Propane Vehicle Demonstration Grants The Propane Vehicle Demonstration Grants was established to demonstrate the benefits of new propane equipment. The US Department of Energy, the Propane Education & Research Council (PERC) and the Propane Vehicle Council (PVC) partnered in this program. The project impacted ten different states, 179 vehicles, and 15 new propane fueling facilities. Based on estimates provided, this project generated a minimum of 1,441,000 new gallons of propane sold for the vehicle market annually. Additionally, two new off-road engines were brought to the market. Projects originally funded under this project were the City of Portland, Colorado, Kansas City, Impco Technologies, Jasper Engines, Maricopa County, New Jersey State, Port of Houston, Salt Lake City Newspaper, Suburban Propane, Mutual Liquid Propane and Ted Johnson.

  19. 76 FR 2147 - UAW-Chrysler National Training Center Technology Training Joint Programs Staff, Detroit, MI; UAW...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-12

    ... Employment and Training Administration UAW-Chrysler National Training Center Technology Training Joint Programs Staff, Detroit, MI; UAW-Chrysler Technical Training Center Technology Training Joint Programs... UAW-Chrysler National Training Center, Detroit, ] Michigan (subject firm) to apply for TAA....

  20. 75 FR 2589 - Petition for Exemption From the Federal Motor Vehicle Theft Prevention Standard; Chrysler

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-15

    ... identity, design, and location of the components of the antitheft device for the new vehicle line. Chrysler... addition to the design and production validation test criteria, Chrysler stated that the SKIS also... Liberty, a similar 5-door, All Wheel Drive, crossover/ Sport Utility Vehicle as the Jeep Patriot...

  1. 75 FR 60138 - Chrysler Financial Services Americas, LLC, a Subsidiary of Finco Intermediate Holding Co., LLC...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Chrysler Financial Services Americas, LLC, a Subsidiary of Finco Intermediate Holding Co., LLC, Troy Customer Contact Center, Troy, Michigan; Notice of...

  2. 77 FR 11194 - Surety Companies Acceptable on Federal Bonds-Name Change: Chrysler Insurance Company

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-24

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE TREASURY Fiscal Service Surety Companies Acceptable on Federal Bonds--Name Change: Chrysler Insurance Company AGENCY: Financial Management Service, Fiscal Service, Department of the Treasury. ACTION: Notice....

  3. Propane-d6 Heterogeneously Hyperpolarized by Parahydrogen

    PubMed Central

    2015-01-01

    Long-lived spin states of hyperpolarized propane-d6 gas were demonstrated following pairwise addition of parahydrogen gas to propene-d6 using heterogeneous parahydrogen-induced polarization (HET-PHIP). Hyperpolarized molecules were synthesized using Rh/TiO2 solid catalyst with 1.6 nm Rh nanoparticles. Hyperpolarized (PH ∼ 1%) propane-d6 was detected at high magnetic field (9.4 T) spectroscopically and by high-resolution 3D gradient-echo MRI (4.7 T) as the gas flowed through the radiofrequency coil with a spatial and temporal resolution of 0.5 × 0.5 × 0.5 mm3 and 17.7 s, respectively. Stopped-flow hyperpolarized propane-d6 gas was also detected at 0.0475 T with an observed nuclear spin polarization of PH ∼ 0.1% and a relatively long lifetime with T1,eff = 6.0 ± 0.3 s. Importantly, it was shown that the hyperpolarized protons of the deuterated product obtained via pairwise parahydrogen addition could be detected directly at low magnetic field. Importantly, the relatively long low-field T1,eff of HP propane-d6 gas is not susceptible to paramagnetic impurities as tested by exposure to ∼0.2 atm oxygen. This long lifetime and nontoxic nature of propane gas could be useful for bioimaging applications including potentially pulmonary low-field MRI. The feasibility of high-resolution low-field 2D gradient-echo MRI was demonstrated with 0.88 × 0.88 mm2 spatial and ∼0.7 s temporal resolution, respectively, at 0.0475 T. PMID:25506406

  4. 76 FR 22729 - Chrysler Group, LLC, Power Train Division, Mack Avenue Engine Plant #1, Including On-Site Leased...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-22

    ... Employment and Training Administration Chrysler Group, LLC, Power Train Division, Mack Avenue Engine Plant 1... to Apply for Worker Adjustment Assistance on April 6, 2011, applicable to workers of Chrysler Group, LLC, Power Train Division, Mack Avenue Engine Plant 1, including on-site leased workers of...

  5. Chrysler Partners with North Lake High School in an Advanced Manufacturing Technology Program for Special Needs Students.

    ERIC Educational Resources Information Center

    Karbon, Patrick J.; Kuhn, Cynthia

    1996-01-01

    Chrysler Corporation and North Lake High School cooperated to develop and deploy Advanced Manufacturing Technology for high school students identified as at risk or hard to serve. Chrysler provided curriculum that was delivered by training center instructors; teachers ensured student competence in academic areas. (JOW)

  6. 75 FR 51845 - Chrysler Group, LLC Manufacturing Division St. Louis North Plant Including On-Site Leased Workers...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-23

    ...] Chrysler Group, LLC Manufacturing Division St. Louis North Plant Including On-Site Leased Workers From American Food, G4S Wackenhut, C R Associates, Syncreon, Robinson Solutions and Dupont Performance Coatings..., applicable to workers of Chrysler Group, LLC, Manufacturing Division, St. Louis North Plant, including...

  7. Chrysler: Save Energy Now Assessment Enables a Vehicle Assembly Complex to Achieve Significant Natural Gas Savings

    SciTech Connect

    2008-02-01

    This DOE Save Energy Now case study describes how Chrysler LLC saves more than 70,000 MMBtu and $627,000 annually after increasing the steam system energy efficiency of a truck and minivan assembly plant in St. Louis, Missouri.

  8. 77 FR 8944 - Chrysler Group, LLC, Receipt of Petition for Decision of Inconsequential Noncompliance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ....3(d) of Federal Motor Vehicle Safety Standard (FMVSS) No. 110, Tire selection and rims and motor home/recreation vehicle trailer load carrying capacity information for motor vehicles with a GVWR of 4... this noncompliance is inconsequential to motor vehicle safety. Chrysler's petition is published...

  9. Baseline fuel economy and emissions tests of a Chrysler 1978, 225 CID engine. Final report

    SciTech Connect

    Gagne, G.; Bell, M.; Walter, R.

    1980-09-01

    This document reports on baseline engine tests of a Chrysler 1978, 225 CID, six-cylinder engine. The tests were conducted in the Automotive Research Laboratory at the Transportation Systems Center. Test results presented herein are also filed on computer-based tapes (9-track ASC II).

  10. Costs Associated With Propane Vehicle Fueling Infrastructure

    SciTech Connect

    Smith, M.; Gonzales, J.

    2014-08-05

    This document is designed to help fleets understand the cost factors associated with propane vehicle fueling infrastructure. It provides an overview of the equipment and processes necessary to develop a propane fueling station and offers estimated cost ranges.

  11. Costs Associated With Propane Vehicle Fueling Infrastructure

    SciTech Connect

    Smith, M.; Gonzales, J.

    2014-08-01

    This document is designed to help fleets understand the cost factors associated with propane vehicle fueling infrastructure. It provides an overview of the equipment and processes necessary to develop a propane fueling station and offers estimated cost ranges.

  12. DaimlerChrysler builds a mine-duty Dodge Ram trucks

    SciTech Connect

    Fiscor, S.

    2006-10-15

    Automotive and engine OEMS worked together with the mines to develop a diesel-powered underground pickup truck that meets emissions standards. The article relates how DaimlerChrysler and Cummins eventually managed to redesign the engine for the Dodge Ram truck to satisfy the new HD10 onroad Environmental Protection Agency regulations for diesel engines that come into force in January 2007. Classic Motors in Richfield, Utah modifies Dodge Ram pickups for use as mantrips and service vehicles. 4 photos.

  13. Silane-propane ignitor/burner

    DOEpatents

    Hill, Richard W.; Skinner, Dewey F.; Thorsness, Charles B.

    1985-01-01

    A silane propane burner for an underground coal gasification process which is used to ignite the coal and to controllably retract the injection point by cutting the injection pipe. A narrow tube with a burner tip is positioned in the injection pipe through which an oxidant (oxygen or air) is flowed. A charge of silane followed by a supply of fuel, such as propane, is flowed through the tube. The silane spontaneously ignites on contact with oxygen and burns the propane fuel.

  14. Silane-propane ignitor/burner

    DOEpatents

    Hill, R.W.; Skinner, D.F. Jr.; Thorsness, C.B.

    1983-05-26

    A silane propane burner for an underground coal gasification process which is used to ignite the coal and to controllably retract the injection point by cutting the injection pipe. A narrow tube with a burner tip is positioned in the injection pipe through which an oxidant (oxygen or air) is flowed. A charge of silane followed by a supply of fuel, such as propane, is flowed through the tube. The silane spontaneously ignites on contact with oxygen and burns the propane fuel.

  15. Numerical and experimental analysis of propane-hydrogen mixture ignition in air

    NASA Astrophysics Data System (ADS)

    Sevrouk, K. L.; Krivosheyev, P. N.; Penyazkov, O. G.; Torohov, S. A.; Titova, N. S.; Starik, A. M.

    2016-11-01

    The addition of hydrogen to the various hydrocarbon fuels being examined as a promising method for increasing the efficiency of the engine while improving their emission characteristics. This work is dedicated to experimental investigation of the ignition delay time C3H8-H2 mixture in the air and analysis of the mechanisms responsible for the acceleration of chain reactions with the addition of hydrogen in propane, based on numerical simulation.

  16. Workplace Communication Skills, Workplace Basic Skills, & Literacy Training in UAW-Chrysler Region 3. Final Performance Report.

    ERIC Educational Resources Information Center

    Indiana Vocational Technical Coll., Indianapolis.

    A workplace literacy partnership program model was demonstrated at four Chrysler plants in Indiana. Objectives were to improve workers' individual skills, enhance personal productivity, and increase work force job security and plant competitiveness. During the 3-month start-up phase, project staff worked with management and labor representatives…

  17. 75 FR 11915 - Chrysler LLC; Trenton Engine Plant, Including On-Site Leased Workers From Caravan Knight...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... certification to include workers leased from Caravan Knight Facilities Management, LLC, working on-site at the... Employment and Training Administration Chrysler LLC; Trenton Engine Plant, Including On-Site Leased Workers... To Apply for Worker Adjustment Assistance In accordance with Section 223 of the Trade Act of 1974,...

  18. Dedicated Deployable Aerobraking Structure

    NASA Technical Reports Server (NTRS)

    Giersch, Louis R.; Knarr, Kevin

    2010-01-01

    A dedicated deployable aerobraking structure concept was developed that significantly increases the effective area of a spacecraft during aerobraking by up to a factor of 5 or more (depending on spacecraft size) without substantially increasing total spacecraft mass. Increasing the effective aerobraking area of a spacecraft (without significantly increasing spacecraft mass) results in a corresponding reduction in the time required for aerobraking. For example, if the effective area of a spacecraft is doubled, the time required for aerobraking is roughly reduced to half the previous value. The dedicated deployable aerobraking structure thus enables significantly shorter aerobraking phases, which results in reduced mission cost, risk, and allows science operations to begin earlier in the mission.

  19. 75 FR 14131 - Effect on Propane Consumers of the Propane Education and Research Council's Operations, Market...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-24

    ..., agricultural, process and nonfuel users of propane. This notice of inquiry is part of an effort to collect information to fulfill requirements under the Propane Education and Research Act of 1996 that established PERC...., Suite 4053, Washington, DC 20230. FOR FURTHER INFORMATION CONTACT: For questions on the submission...

  20. An unnatural death by propan-1-ol and propan-2-ol.

    PubMed

    Skopp, Gisela; Gutmann, Isabelle; Schwarz, Clara-Sophie; Schmitt, Georg

    2016-07-01

    A fatality of an inpatient ingesting a disinfectant containing ethanol, propan-1-ol, and propan-2-ol is reported. The alleged survival time was about 1 h. Major findings at autopsy were an extended hemorrhagic lung edema, an edematous brain, and shock kidneys. Concentrations of alcohols and acetone, a major metabolite of propan-2-ol, were determined from body fluids (blood from the heart and the femoral vein, urine, gastric contents) and tissues (brain, muscle, liver, kidneys, lungs) by headspace/gas chromatography using 2-methylpropan-2-ol as the internal standard. All samples investigated were positive for propan-1-ol, propan-2-ol, ethanol, and acetone except stomach contents, where acetone was not detectable. The low concentration of acetone compared to propan-2-ol likely supports the short survival time. The concentration ratios estimated from the results are in accordance with the physico-chemical properties of the particular alcohols, their different affinities towards alcohol dehydrogenase as well as their interdependence during biotransformation. Autopsy did not reveal the cause of death. According to the few published data, blood concentrations of 1.44 and 1.70 mg/g of propan-2-ol and propan-1-ol, respectively, are considered sufficient to have caused the death. This case also points to the need to restrict access to antiseptic solutions containing alcohols in wards with patients at risk.

  1. Saturn V Dedication

    NASA Technical Reports Server (NTRS)

    1999-01-01

    A replica of the Saturn V rocket that propelled man from the confines of Earth's gravity to the surface of the Moon was built on the grounds of the U. S. Space and Rocket Center in Huntsville, AL. in time for the 30th arniversary celebration of that historic occasion. Marshall Space Flight Center and its team of German rocket scientists headed by Dr. Wernher von Braun were responsible for the design and development of the Saturn V rocket. Pictured are MSFC's current Center Director Art Stephenson, Alabama Congressman Bud Cramer, and NASA Administrator Dan Goldin during the dedication ceremony.

  2. Saturn V Dedication

    NASA Technical Reports Server (NTRS)

    1999-01-01

    A replica of the Saturn V rocket that propelled man from the confines of Earth's gravity to the surface of the Moon was built on the grounds of the U. S. Space and Rocket Center in Huntsville, AL. in time for the 30th arniversary celebration of that historic occasion. Marshall Space Flight Center and its team of German rocket scientists headed by Dr. Wernher von Braun were responsible for the design and development of the Saturn V rocket. Pictured are MSFC's current Center Director Art Stephenson, Alabama Congressman Bud Cramer, NASA Administrator Dan Goldin, and director of the U. S. Space and Rocket Center Mike Wing during the dedication ceremony.

  3. Marine Science Building Dedicated

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Officials cut the ribbon during dedication ceremonies of the George A. Knauer Marine Science Building on Oct. 17 at NASA Stennis Space Center (SSC). The $2.75 million facility, the first building at the test site funded by the state of Mississippi, houses six science labs, classrooms and office space for 40 faculty and staff. Pictured are, from left, Rear Adm. Thomas Donaldson, commander of the Naval Meteorology and Oceanography Command; SSC Assistant Director David Throckmorton; Dr. George A. Knauer, founder of the Center of Marine Science at the University of Southern Mississippi (USM); Lt. Gov. Amy Tuck; and USM President Dr. Shelby Thames.

  4. RMP Guidance for Propane Storage Facilities - Main Text

    EPA Pesticide Factsheets

    This document is intended as comprehensive Risk Management Program guidance for larger propane storage or distribution facilities who already comply with propane industry standards. Includes sample RMP, and release calculations.

  5. . . . While Others Conserve Cash by Converting from Gasoline to Propane.

    ERIC Educational Resources Information Center

    Rasmussen, Scott A.

    1988-01-01

    Since 1983, when the David Douglas Public Schools (Portland, Oregon) converted 30 buses to propane fuel, the district has saved $75,000 in fuel and maintenance costs. Propane is priced consistently lower than gasoline and burns cleaner. Since propane engines do not require a carburetor, there are fewer maintenance problems. (MLH)

  6. Case Study - Propane School Bus Fleets

    SciTech Connect

    Laughlin, M; Burnham, A.

    2014-08-31

    As part of the U.S. Department of Energy’s (DOE’s) effort to deploy transportation technologies that reduce U.S. dependence on imported petroleum, this study examines five school districts, one in Virginia and four in Texas, successful use of propane school buses. These school districts used school buses equipped with the newly developed liquid propane injection system that improves vehicle performance. Some of the school districts in this study saved nearly 50% on a cost per mile basis for fuel and maintenance relative to diesel. Using Argonne National Laboratory’s Alternative Fuel Life-Cycle Environmental and Economic Transportation (AFLEET) Tool developed for the DOE’s Clean Cities program to help Clean Cities stakeholders estimate petroleum use, greenhouse gas (GHG) emissions, air pollutant emissions and cost of ownership of light-duty and heavy-duty vehicles, the results showed payback period ranges from 3—8 years, recouping the incremental cost of the vehicles and infrastructure. Overall, fuel economy for these propane vehicles is close to that of displaced diesel vehicles, on an energy-equivalent basis. In addition, the 110 propane buses examined demonstrated petroleum displacement, 212,000 diesel gallon equivalents per year, and GHG benefits of 770 tons per year.

  7. 21 CFR 582.1655 - Propane.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... used in accordance with good manufacturing or feeding practice. ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Propane. 582.1655 Section 582.1655 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS,...

  8. 77 FR 31842 - Thrifty Propane, Inc.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Thrifty Propane, Inc. v. Enterprise TE Products Pipeline Co., LLC; Notice of... Enterprise TE Products Pipeline Co., LLC (Respondent) alleging that the Respondent intends to make...

  9. Portland Public School Children Move with Propane

    SciTech Connect

    Not Available

    2004-04-01

    This 2-page Clean Cities fact sheet describes the use of propane as a fuel source for Portland Public Schools' fleet of buses. It includes information on the history of the program, along with contact information for the local Clean Cities Coordinator and Portland Public Schools.

  10. Case Study - Propane Bakery Delivery Step Vans

    SciTech Connect

    Laughlin, M.; Burnham, A.

    2016-04-01

    A switch to propane from diesel by a major Midwest bakery fleet showed promising results, including a significant displacement of petroleum, a drop in greenhouse gases and a fuel cost savings of seven cents per mile, according to a study recently completed by the U.S. Department of Energy's Argonne National Laboratory for the Clean Cities program.

  11. Dedication - Susan L Greenblatt

    NASA Astrophysics Data System (ADS)

    Guberman, Steven L.

    2011-07-01

    Photo of Susan L Greenblatt Figure 1. Susan in May, 1994 This volume is dedicated to the memory of Susan L Greenblatt, the wife of Steven L Guberman. Susan attended 6 of the 8 dissociative recombination (DR) meetings. Her advice and wise counsel played a vital role in the organization of several of these meetings. The fifth meeting in Chicago in 2001 was her idea and it would not have occurred without her encouragement. Susan was always amused by the memory of the first group dinner at the second DR meeting at St Jacut in 1992. As we went around the dinner table identifying ourselves, it soon became her turn. Susan was a sociologist and after introducing herself she said: "I am not a chemist". A spontaneous chorus of attendees proclaimed "Neither are we!". Her husband and a few other chemists abstained. In 1983, Susan and I established the Institute for Scientific Research (ISR). The name was chosen so as to span sociology and chemical physics. Four years prior, an ophthalmologist had diagnosed a rare retinal condition of unknown origin and advised her to change her profession to one that did not involve reading. (She was able to read for the rest of her life.) Twenty years later we learned that the cause of the retinal and all her other health problems was a recently discovered rare mitochondrial mutation. Her experience with ophthalmologists and her life-long keen sense of injustice, led her to write a grant proposal to the US Department of Education to survey all ophthalmologists in the US to determine whether they were aware of and whether they told their patients about resources and aids that could help them to continue reading and participating in everyday activities. As part of the grant and based upon the survey results, she proposed to set up low-vision training programs for ophthalmology residents. We knew that the competition for funding was intense and included several well-known and more established organizations. Nevertheless, the proposal was funded

  12. Adsorptive separation of propylene-propane mixtures

    SciTech Connect

    Jaervelin, H.; Fair, J.R. )

    1993-10-01

    The separation of propylene-propane mixtures is of great commercial importance and is carried out by fractional distillation. It is claimed to be the most energy-intensive distillation practiced in the United States. The purpose of this paper is to describe experimental work that suggests a practical alternative to distillation for separating the C[sub 3] hydrocarbons: adsorption. As studied, the process involves three adsorptive steps: initial separation with molecular sieves with heavy dilution with an inert gas; separation of propylene and propane separately from the inert gas, using activated carbon; and drying of the product streams with any of several available desiccants. The research information presented here deals with the initial step and includes both equilibrium and kinetic data. Isotherms are provided for propylene and propane adsorbed on three zeolites, activated alumina, silica gel, and coconut-based activated carbon. Breakthrough data are provided for both adsorption and regeneration steps for the zeolites, which were found to be superior to the other adsorbents for breakthrough separations. A flow diagram for the complete proposed process is included.

  13. Titan's Propane from Cassini Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Nixon, C. A.; Jennings, D. E.; Flaud, J.-M.; Bezard, B.; Teanby, N. A.; Irwin, P. G. J.; Ansty, T. M.; Coustenis, A.; Flasar, F. M.

    2009-04-01

    Propane gas (C3H8) was first detected in the atmosphere of Titan by the Voyager 1 IRIS spectrometer, during the 1980 encounter (Maguire et al., 1981), and remains the heaviest saturated hydrocarbon (alkane) found there to date. Although the identification was based on the detection of several bands (including 748, 922, 1054, 1158 cm-1), only the ν26 band at 748 cm-1 has been subsequently modeled to retrieve the abundance, due to the unique availability of its line parameters in the GEISA database (Husson et al. 1992). Subsequent measurements from the ground (Roe et al., 2003) and Earth-orbit (ISO - Coustenis et al. 2003) have also focused on this one band, deriving an abundance of ~0.5 ppm, although it remains compromised by coincidence with the R-branch of the much stronger acetylene (C2H2) gas. The Composite Infrared Spectrometer (CIRS) instrument carried on-board the Cassini spacecraft in Saturn orbit has now been observing Titan during more than 50 flybys over 5 years, and offers a fresh perspective on the prevalence of propane. With much improved spectral and spatial resolution and sensitivity over IRIS, CIRS is also able to perform repeated limb sounding (viewing through the atmosphere above the surface) to increase signal-to-noise still further. Modeling and removal of the emissions of other gases now shows clearly for the first time a multitude of propane bands: including the four seen by IRIS and at least four others (869, 1338, 1376, 1472 cm-1). In addition, a new line atlas for three bands of propane at shorter wavelengths (1300-1500 cm-1) has now been compiled, based on the work of Flaud et al. (2001). With this, we now have the potential to model these weaker bands, and to check the measurements made by CIRS using the 748 cm-1 band alone. Preliminary analysis has shown that the retrievals are very sensitive to the spectral baseline (haze model) assumed, and that existing lab tholin spectral properties (Khare et al. 1984) do not well match the opacity

  14. 09-NIF Dedication: Arnold Schwarzenegger

    ScienceCinema

    Governor Arnold Schwarzenegger

    2016-07-12

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by California Governor Arnold Schwarzenegger.

  15. 10-NIF Dedication: Ellen Tauscher

    ScienceCinema

    Congresswoman Ellen Tauscher

    2016-07-12

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Congresswoman Ellen Tauscher, of California's 10th district, which includes Livermore.

  16. 01-NIF Dedication: George Miller

    ScienceCinema

    George Miller

    2016-07-12

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Lab Director George Miller.

  17. 08-NIF Dedication: Zoe Lofgren

    ScienceCinema

    Congresswoman Zoe Lofgren

    2016-07-12

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Congresswoman Zoe Lofgren, of California's 16th district.

  18. 02-NIF Dedication: Edward Moses

    ScienceCinema

    Edward Moses

    2016-07-12

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by NIF Director Edward Moses.

  19. 11-NIF Dedication: Dianne Feinstein

    ScienceCinema

    U.S. Senator Dianne Feinstein

    2016-07-12

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by U.S. Senator Dianne Feinstein of California.

  20. 02-NIF Dedication: Edward Moses

    SciTech Connect

    Edward Moses

    2009-07-02

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by NIF Director Edward Moses.

  1. 01-NIF Dedication: George Miller

    SciTech Connect

    George Miller

    2009-07-02

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Lab Director George Miller.

  2. 11-NIF Dedication: Dianne Feinstein

    SciTech Connect

    U.S. Senator Dianne Feinstein

    2009-07-02

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by U.S. Senator Dianne Feinstein of California.

  3. 10-NIF Dedication: Ellen Tauscher

    SciTech Connect

    Congresswoman Ellen Tauscher

    2009-07-02

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Congresswoman Ellen Tauscher, of California's 10th district, which includes Livermore.

  4. 08-NIF Dedication: Zoe Lofgren

    SciTech Connect

    Congresswoman Zoe Lofgren

    2009-07-02

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Congresswoman Zoe Lofgren, of California's 16th district.

  5. 09-NIF Dedication: Arnold Schwarzenegger

    SciTech Connect

    Governor Arnold Schwarzenegger

    2009-07-02

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by California Governor Arnold Schwarzenegger.

  6. 77 FR 2293 - AmeriGas Propane, L.P., AmeriGas Propane, Inc., Energy Transfer Partners, L.P., and Energy...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... AmeriGas Propane, L.P., AmeriGas Propane, Inc., Energy Transfer Partners, L.P., and Energy Transfer...'') with AmeriGas Propane, L.P. (``AmeriGas''), AmeriGas Propane, Inc., Energy Transfer Partners, L.P. (``ETP''), and Energy Transfer Partners GP, L.P. (``ETP GP''), which is designed to guard...

  7. Reduced chemical kinetics for propane combustion

    NASA Technical Reports Server (NTRS)

    Ying, Shuh-Jing; Nguyen, Hung Lee

    1990-01-01

    It is pointed out that a detailed chemical kinetics mechanism for the combustion of propane consists of 40 chemical species and 118 elementary chemical reactions. An attempt is made to reduce the number of chemical species and elementary chemical reactions so that the computer run times and storage requirements may be greatly reduced in three-dimensional gas turbine combustion flow calculations, while maintaining accurate predictions of the propane combustion and exhaust emissions. By way of a sensitivity analysis, the species of interest and chemical reactions are classified in descending order of importance. Nineteen species are chosen, and their pressure, temperature, and concentration profiles are presented for the reduced mechanisms, which are then compared with those from the full 118 reactions. It is found that 45 reactions involving 27 species have to be kept for comparable agreement. A comparison of the results obtained from the 45 reactions to that of the full 118 shows that the pressure and temperature profiles and concentrations of C3H8, O2, N2, H2O, CO, and CO2 are within 10 percent of maximum change.

  8. Extending the Lifetime of Hyperpolarized Propane Gas through Reversible Dissolution.

    PubMed

    Burueva, Dudari B; Romanov, Alexey S; Salnikov, Oleg G; Zhivonitko, Vladimir V; Chen, Yu-Wen; Barskiy, Danila A; Chekmenev, Eduard Y; Hwang, Dennis W; Kovtunov, Kirill V; Koptyug, Igor V

    2017-03-02

    Hyperpolarized (HP) propane produced by the parahydrogen-induced polarization (PHIP) technique has been recently introduced as a promising contrast agent for functional lung magnetic resonance (MR) imaging. However, its short lifetime due to a spin-lattice relaxation time T1 of less than 1 s in the gas phase is a significant translational challenge for its potential biomedical applications. The previously demonstrated approach for extending the lifetime of the HP propane state through long-lived spin states allows the HP propane lifetime to be increased by a factor of ∼3. Here, we demonstrate that a remarkable increase in the propane hyperpolarization decay time at high magnetic field (7.1 T) can be achieved by its dissolution in deuterated organic solvents (acetone-d6 or methanol-d4). The approximate values of the HP decay time for propane dissolved in acetone-d6 are 35.1 and 28.6 s for the CH2 group and the CH3 group, respectively (similar values were obtained for propane dissolved in methanol-d4), which are ∼50 times larger than the gaseous propane T1 value. Furthermore, we show that it is possible to retrieve HP propane from solution to the gas phase with the preservation of hyperpolarization.

  9. 03-NIF Dedication: Norm Pattiz

    ScienceCinema

    Norm Pattiz

    2016-07-12

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Norm Pattiz, the chairman of Lawrence Livermore National Security, which manages Lawrence Livermore National Laboratory for the U.S. Department of Energy.

  10. 06-NIF Dedication: Steven Koonin

    ScienceCinema

    Steven Koonin

    2016-07-12

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Steven Koonin, the undersecretary for science of the U.S. Department of Energy.

  11. 06-NIF Dedication: Steven Koonin

    SciTech Connect

    Steven Koonin

    2009-07-02

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Steven Koonin, the undersecretary for science of the U.S. Department of Energy.

  12. 03-NIF Dedication: Norm Pattiz

    SciTech Connect

    Norm Pattiz

    2009-07-02

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Norm Pattiz, the chairman of Lawrence Livermore National Security, which manages Lawrence Livermore National Laboratory for the U.S. Department of Energy.

  13. Study on propane-butane gas storage by hydrate technology

    NASA Astrophysics Data System (ADS)

    Hamidi, Nurkholis; Wijayanti, Widya; Widhiyanuriyawan, Denny

    2016-03-01

    Different technology has been applied to store and transport gas fuel. In this work the storage of gas mixture of propane-butane by hydrate technology was studied. The investigation was done on the effect of crystallizer rotation speed on the formation of propane-butane hydrate. The hydrates were formed using crystallizer with rotation speed of 100, 200, and 300 rpm. The formation of gas hydrates was done at initial pressure of 3 bar and temperature of 274K. The results indicated that the higher rotation speed was found to increase the formation rate of propane-butane hydrate and improve the hydrates stability.

  14. Temperature-dependent high resolution absorption cross sections of propane

    NASA Astrophysics Data System (ADS)

    Beale, Christopher A.; Hargreaves, Robert J.; Bernath, Peter F.

    2016-10-01

    High resolution (0.005 cm-1) absorption cross sections have been measured for pure propane (C3H8). These cross sections cover the 2550-3500 cm-1 region at five temperatures (from 296 to 700 K) and were measured using a Fourier transform spectrometer and a quartz cell heated by a tube furnace. Calibrations were made by comparison to the integrated cross sections of propane from the Pacific Northwest National Laboratory. These are the first high resolution absorption cross sections of propane for the 3 μm region at elevated temperatures. The cross sections provided may be used to monitor propane in combustion environments and in astronomical sources such as the auroral regions of Jupiter, brown dwarfs and exoplanets.

  15. 2. View of Liquified Propane Air Plant (New), former Exhaust ...

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

    2. View of Liquified Propane Air Plant (New), former Exhaust and Compressor Building and former Purifying Plant in background. - Concord Gas Light Company, South Main Street, Concord, Merrimack County, NH

  16. Wind profiler dedicated in Indonesia

    NASA Astrophysics Data System (ADS)

    Gage, Ken

    A dedication ceremony was recently held in Biak, Indonesia, to commemorate the opening of the Biak VHF wind profiler. The wind profiler, which operates at 50 MHz, was constructed by the National Oceanic and Atmospheric Administration's Aeronomy Laboratory in cooperation with the Indonesian National Institute of Aeronautics and Space (LAPAN). The Biak facility completes the NOAA'Colorado University trans-Pacific wind-profiler network. Other stations in the network, which is sponsored by the National Science Foundation, are Piura, Peru; Pohnpei, Federated States of Micronesia; and Christmas Island in Kirabati. The Christmas Island facility is supported by NOAA's Tropical Ocean and Global Atmosphere (TOGA) Program Project Office.

  17. A Detailed Modeling Study of Propane Oxidation

    SciTech Connect

    Westbrook, C K; Jayaweera, T M; Pitz, W J; Curran, H J

    2004-03-19

    A detailed chemical kinetic mechanism has been used to simulate ignition delay times recorded by a number of experimental shock tube studies over the temperature range 900 {le} T {le} 1800 K, in the pressure range 0.75-40 atm and in the equivalence ratio range 0.5 {le} {phi} {le} 2.0. Flame speed measurements at 1 atm in the equivalence ratio range 0.4 {le} {phi} {le} 1.8 have also been simulated. Both of these data sets, particularly those recorded at high pressure, are of particular importance in validating a kinetic mechanism, as internal combustion engines operate at elevated pressures and temperatures and rates of fuel oxidation are critical to efficient system operation. Experiments in which reactant, intermediate and product species were quantitatively recorded, versus temperature in a jet-stirred reactor (JSR) and versus time in a flow reactor are also simulated. This data provide a stringent test of the kinetic mechanism as it must reproduce accurate quantitative profiles for all reactant, intermediate and product species. The JSR experiments were performed in the temperature range 1000-1110 K, in the equivalence ratio range 0.5 {le} {phi} {le} 4.0, at a pressure of 5 atm. These experiments are complemented by those carried out in a flow reactor in the temperature range 660-820 K, at 10 atm and at an equivalence ratio of 0.4. In addition, burner stabilized flames were simulated, where chemical species profiles were measured at atmospheric pressure for two propane-air flat flames. Overall, reasonably good agreement is observed between the model simulations and the experimental results.

  18. New Formulation for the Viscosity of Propane

    NASA Astrophysics Data System (ADS)

    Vogel, Eckhard; Herrmann, Sebastian

    2016-12-01

    A new viscosity formulation for propane, using the reference equation of state for its thermodynamic properties by Lemmon et al. [J. Chem. Eng. Data 54, 3141 (2009)] and valid in the fluid region from the triple-point temperature to 650 K and pressures up to 100 MPa, is presented. At the beginning, a zero-density contribution and one for the critical enhancement, each based on the experimental data, were independently generated in parts. The higher-density contributions are correlated as a function of the reciprocal reduced temperature τ = Tc/T and of the reduced density δ = ρ/ρc (Tc—critical temperature, ρc—critical density). The final formulation includes 17 coefficients inferred by applying a state-of-the-art linear optimization algorithm. The evaluation and choice of the primary data sets are detailed due to its importance. The viscosity at low pressures p ≤ 0.2 MPa is represented with an expanded uncertainty of 0.5% (coverage factor k = 2) for temperatures 273 ≤ T/K ≤ 625. The expanded uncertainty in the vapor phase at subcritical temperatures T ≥ 273 K as well as in the supercritical thermodynamic region T ≤ 423 K at pressures p ≤ 30 MPa is assumed to be 1.5%. In the near-critical region (1.001 < 1/τ < 1.010 and 0.8 < δ < 1.2), the expanded uncertainty increases with decreasing temperature up to 3.0%. It is further increased to 4.0% in regions of less reliable primary data sets and to 6.0% in ranges in which no primary data are available but the equation of state is valid. Tables of viscosity computed for the new formulation are given in an Appendix for the single-phase region, for the vapor-liquid phase boundary, and for the near-critical region.

  19. The TNT equivalence of an optimum propane oxygen mixture

    NASA Astrophysics Data System (ADS)

    Dewey, J. M.

    2005-12-01

    Measurements of the times of arrival of the primary shock produced by the explosion of a nominal 20 tn propane-oxygen mixture have been analysed to provide the variation of the peak hydrostatic overpressure as a function of distance. The results have been scaled to those for a charge of unit mass at normal temperature and pressure, based on the masses of the propane and oxygen and of the propane alone. The scaled results are compared with those produced by the explosion of a hemispherical unit mass of TNT to provide the TNT equivalence factor as a function of overpressure and distance. For overpressures greater than 1 atm there is a strong dependence on the distance from the centre of the explosion, but at lower overpressures the equivalence factors have almost constant values of 0.55 for the propane-oxygen mixture and 1.95 for the propane alone. The significance of these findings, in relationship to vapour cloud explosions and boiling liquid expanding vapour explosions, is discussed.

  20. An engineered pathway for the biosynthesis of renewable propane.

    PubMed

    Kallio, Pauli; Pásztor, András; Thiel, Kati; Akhtar, M Kalim; Jones, Patrik R

    2014-09-02

    The deployment of next-generation renewable biofuels can be enhanced by improving their compatibility with the current infrastructure for transportation, storage and utilization. Propane, the bulk component of liquid petroleum gas, is an appealing target as it already has a global market. In addition, it is a gas under standard conditions, but can easily be liquefied. This allows the fuel to immediately separate from the biocatalytic process after synthesis, yet does not preclude energy-dense storage as a liquid. Here we report, for the first time, a synthetic metabolic pathway for producing renewable propane. The pathway is based on a thioesterase specific for butyryl-acyl carrier protein (ACP), which allows native fatty acid biosynthesis of the Escherichia coli host to be redirected towards a synthetic alkane pathway. Propane biosynthesis is markedly stimulated by the introduction of an electron-donating module, optimizing the balance of O2 supply and removal of native aldehyde reductases.

  1. An engineered pathway for the biosynthesis of renewable propane

    PubMed Central

    Kallio, Pauli; Pásztor, András; Thiel, Kati; Akhtar, M. Kalim; Jones, Patrik R.

    2014-01-01

    The deployment of next-generation renewable biofuels can be enhanced by improving their compatibility with the current infrastructure for transportation, storage and utilization. Propane, the bulk component of liquid petroleum gas, is an appealing target as it already has a global market. In addition, it is a gas under standard conditions, but can easily be liquefied. This allows the fuel to immediately separate from the biocatalytic process after synthesis, yet does not preclude energy-dense storage as a liquid. Here we report, for the first time, a synthetic metabolic pathway for producing renewable propane. The pathway is based on a thioesterase specific for butyryl-acyl carrier protein (ACP), which allows native fatty acid biosynthesis of the Escherichia coli host to be redirected towards a synthetic alkane pathway. Propane biosynthesis is markedly stimulated by the introduction of an electron-donating module, optimizing the balance of O2 supply and removal of native aldehyde reductases. PMID:25181600

  2. Oxidative dehydrogenation of propane over Mg-Mo-O catalysts

    SciTech Connect

    Cadus, L.E.; Abello, M.C.; Gomez, M.F.; Rivarola, J.B.

    1996-01-01

    Mg-Mo-O catalysts have been investigated with different techniques (XRD, XPS, IR, and EPR spectroscopies) in order to explain the difference in catalytic behavior in the oxidative dehydrogenation of propane to propene. The active site would be a coordinatively unsaturated form of Mo{sup 5+}. The active Mo{sup 5+} could be generated on the surface by propane reduction. The slight excess of MoO{sub 3} which is necessary for the catalyst to become an active one probably contributes to the formation of Mo{sup 5+}.

  3. Three new olanzapine structures: the acetic acid monosolvate, and the propan-2-ol and propan-2-one hemisolvate monohydrates.

    PubMed

    Bojarska, Joanna; Maniukiewicz, Waldemar; Sieroń, Lesław

    2013-07-01

    The crystal structures of three new solvates of olanzapine [systematic name: 2-methyl-4-(4-methylpiperazin-1-yl)-10H-thieno[2,3-b][1,5]benzodiazepine], namely olanzapine acetic acid monosolvate, C17H20N4S·C2H4O2, (I), olanzapine propan-2-ol hemisolvate monohydrate, C17H20N4S·0.5C3H8O·H2O, (II), and olanzapine propan-2-one hemisolvate monohydrate, C17H20N4S·0.5C3H6O·H2O, (III), are presented and compared with other known olanzapine forms. There is a fairly close resemblance of the molecular conformation for all studied analogues. The crystal structures are built up through olanzapine dimers, which are characterized via C-H...π interactions between the aliphatic fragment (1-methylpiperazin-4-yl) and the aromatic fragment (benzene system). All solvent (guest) molecules participate in hydrogen-bonding networks. The crystal packing is sustained via intermolecular N(host)-H···O(guest), O(guest)-H···N(host), O(guest)-H···O(guest) and C(host)-H···O(guest) hydrogen bonds. It should be noted that the solvent propan-2-ol in (II) and propan-2-one in (III) show orientational disorder. The propan-2-ol molecule lies close to a twofold axis, while the propan-2-one molecule resides strictly on a twofold axis through the carbonyl C atom. In both cases, the water molecules present positional disorder of the H atoms.

  4. 40 CFR 721.10339 - Adipic acid, substituted propane, alkyldiol, acrylate (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Adipic acid, substituted propane... Significant New Uses for Specific Chemical Substances § 721.10339 Adipic acid, substituted propane, alkyldiol... substance identified generically as adipic acid, substituted propane, alkyldiol, acrylate (PMN P-04-113)...

  5. 40 CFR 721.10339 - Adipic acid, substituted propane, alkyldiol, acrylate (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Adipic acid, substituted propane... Significant New Uses for Specific Chemical Substances § 721.10339 Adipic acid, substituted propane, alkyldiol... substance identified generically as adipic acid, substituted propane, alkyldiol, acrylate (PMN P-04-113)...

  6. 40 CFR 721.10339 - Adipic acid, substituted propane, alkyldiol, acrylate (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Adipic acid, substituted propane... Significant New Uses for Specific Chemical Substances § 721.10339 Adipic acid, substituted propane, alkyldiol... substance identified generically as adipic acid, substituted propane, alkyldiol, acrylate (PMN P-04-113)...

  7. Zeolitic imidazolate frameworks for kinetic separation of propane and propene

    DOEpatents

    Li, Jing; Li, Kunhao; Olson, David H.

    2014-08-05

    Zeolitic Imidazolate Frameworks (ZIFs) characterized by organic ligands consisting of imidazole ligands that are either essentially all 2-chloroimidazole ligands or essentially all 2-bromoimidazole ligands are disclosed. Methods for separating propane and propene with the ZIFs of the present invention, as well as other ZIFs, are also disclosed.

  8. Fuel economy and exhaust emissions characteristics of diesel vehicles: Test results of a prototype Chrysler Volare, 225 CID (3.7-liter) automobile

    NASA Technical Reports Server (NTRS)

    Walter, R. A.

    1982-01-01

    The results obtained from fuel economy and emission tests conducted on a prototype Chrysler Volare diesel vehicle are documented. The vehicle was tested on a chassis dynamometer over selected drive cycles and steady-state conditions. The fuel used, was a DOE/BETC referee fuel. Particulate emission rates were calculated from dilution tunnel measurements and large volume particulate samples were collected for biological and chemical analysis. The vehicle obtained 32.7 mpg for the FTP urban cycle and 48.8 mpg for the highway cycle. The emissions rates were 0.42/1.58/1.17/0.28 g/mile of HC, CO, NOx and particulates respectively.

  9. Press Site Auditorium dedicated to John Holliman

    NASA Technical Reports Server (NTRS)

    1999-01-01

    A ceremony dedicated the KSC Press Site auditorium as the John Holliman Auditorium to honor the correspondent for his enthusiastic, dedicated coverage of America's space program. The auditorium was built in 1980 and has been the focal point for new coverage of Space Shuttle launches. The ceremony followed the 94th launch of a Space Shuttle, on mission STS-96, earlier this morning.

  10. Processing of polyolefin blends in supercritical propane solution

    NASA Astrophysics Data System (ADS)

    Han, Suh Joon

    New polymer blending methods are developed and studied by processing polyolefins in supercritical propane in this research. Polypropylene and ethylene copolymers were dissolved in supercritical propane, and processed via various paths and reactions, i.e., RESS (rapid expansion of supercritical solution), ICSS (isobaric crystallization from supercritical solution), and thermoplastic vulcanizate (TPV) formation. Each process resulted in a unique morphology of polyolefin blends. The effect of polyolefin microstructure on the solution behavior in supercritical propane was investigated, and the relationship between the morphology of the polyolefin blends and processing paths in supercritical propane solutions was established. To understand the thermodynamic properties of polyolefins in bulk and solutions, the solubility parameter was estimated by measurement of the internal pressure from the experimental P-V-T data for polyolefins in the melt state. As the short chain branch content in the ethylene copolymers increased, the internal pressure decreased. The cloud-point pressures of binary polymer solutions in propane decreased as the extent of short chain branching increased in the ethylene copolymers. At the same degree of branching, the cloud-point pressure decreased slightly with increasing branch length. The cloud-point pressures of a ternary polymer solution in the pressure-temperature phase diagrams were higher than those of binary polymer solutions at the same composition (indicating poorer solubility). Microfibers and microparticles (10 ˜ 50 mum diameter) were precipitated from the RESS process while microcellular foams were obtained from the ICSS process. The phase domains of the ethylene-butene (EB) copolymer in the polypropylene from the RESS process were smaller for highly branched EB copolymer. The surface morphology of ethylene copolymers in the microcelluar foams was also changed by increasing the branch content from microparticles to a viscous layer. New

  11. Gas Phase UTE MRI of Propane and Propene

    PubMed Central

    Kovtunov, Kirill V.; Romanov, Alexey S.; Salnikov, Oleg G.; Barskiy, Danila A.; Chekmenev, Eduard Y.; Koptyug, Igor V.

    2016-01-01

    1H MRI of gases can potentially enable functional lung imaging to probe gas ventilation and other functions. In this work, 1H MR images of hyperpolarized and thermally polarized propane gas were obtained using UTE (ultrashort echo time) pulse sequence. A 2D image of thermally polarized propane gas with ~0.9×0.9 mm2 spatial resolution was obtained in less than 2 seconds, demonstrating that even non-hyperpolarized hydrocarbon gases can be successfully utilized for conventional proton MRI. The experiments were also performed with hyperpolarized propane gas and demonstrated acquisition of high-resolution multi-slice FLASH 2D images in ca. 510 s and non slice-selective 2D UTE MRI images in ca. 2 s. The UTE approach adopted in this study can be potentially used for medical lung imaging. Furthermore, the possibility to combine UTE with selective suppression of 1H signals from one of the two gases in a mixture is demonstrated in this MRI study. The latter can be useful for visualizing industrially important processes where several gases may be present, e.g., gas-solid catalytic reactions. PMID:27478870

  12. Differential microbial transformation of nitrosamines by an inducible propane monooxygenase.

    PubMed

    Homme, Carissa L; Sharp, Jonathan O

    2013-07-02

    The toxicity of N-nitrosamines, their presence in drinking and environmental water supplies, and poorly understood recalcitrance collectively necessitate a better understanding of their potential for bioattenuation. Here, we show that the bacterial strain Rhodococcus jostii RHA1 can biotransform N-nitrosodiethylamine (NDEA), N-nitrosodi-n-propylamine (NDPA), N-nitrosopyrrolidine (NPYR), and possibly N-nitrosomorpholine (NMOR) in addition to N-nitrosodimethylamine (NDMA). Growth of cells on propane as the sole carbon source greatly enhanced degradation rates when contrasted with cells grown on complex organics. Propane-induced rates in order of fastest to slowest were NDMA > NDEA > NDPA > NPYR > NMOR at concentrations <2000 μg/L. Removal rates for linear functional groups scaled inversely with mass and cyclic nitrosamines were more recalcitrant than linear nitrosamines. Controls demonstrated significant NDEA and NDPA losses independent of biomass, suggesting abiotic processes may play a role in attenuation of these two compounds under experimental conditions tested here. In contrast to NDMA, a transition from first to zero order kinetics was not observed for the other nitrosamines included in this study over a concentration range of 20-2000 μg/L. A genetic knockout for the propane monooxygenase enzyme (PrMO) confirmed the role of this enzyme in the biotransformation of NDEA and NPYR. This study furthers our understanding of environmental nitrosamine attenuation by revealing an enzymatic mechanism for the biotransformation of multiple nitrosamines, their relative recalcitrance to transformation, and potential for abiotic loss.

  13. 12-NIF Dedication: Concluding remarks and video

    SciTech Connect

    Edward Moses

    2009-07-02

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the concluding remarks by NIF Director Edward Moses, and a brief video presentation.

  14. 12-NIF Dedication: Concluding remarks and video

    ScienceCinema

    Edward Moses

    2016-07-12

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the concluding remarks by NIF Director Edward Moses, and a brief video presentation.

  15. Breast-Dedicated Radionuclide Imaging Systems.

    PubMed

    Hsu, David F C; Freese, David L; Levin, Craig S

    2016-02-01

    Breast-dedicated radionuclide imaging systems show promise for increasing clinical sensitivity for breast cancer while minimizing patient dose and cost. We present several breast-dedicated coincidence-photon and single-photon camera designs that have been described in the literature and examine their intrinsic performance, clinical relevance, and impact. Recent tracer development is mentioned, results from recent clinical tests are summarized, and potential areas for improvement are highlighted.

  16. Experimental study on transmission of an overdriven detonation wave from propane/oxygen to propane/air

    SciTech Connect

    Li, J.; Lai, W.H.; Chung, K.; Lu, F.K.

    2008-08-15

    Two sets of experiments were performed to achieve a strong overdriven state in a weaker mixture by propagating an overdriven detonation wave via a deflagration-to-detonation transition (DDT) process. First, preliminary experiments with a propane/oxygen mixture were used to evaluate the attenuation of the overdriven detonation wave in the DDT process. Next, experiments were performed wherein a propane/oxygen mixture was separated from a propane/air mixture by a thin diaphragm to observe the transmission of an overdriven detonation wave. Based on the characteristic relations, a simple wave intersection model was used to calculate the state of the transmitted detonation wave. The results showed that a rarefaction effect must be included to ensure that there is no overestimate of the post-transmission wave properties when the incident detonation wave is overdriven. The strength of the incident overdriven detonation wave plays an important role in the wave transmission process. The experimental results showed that a transmitted overdriven detonation wave occurs instantaneously with a strong incident overdriven detonation wave. The near-CJ state of the incident wave leads to a transmitted shock wave, and then the transition to the overdriven detonation wave occurs downstream. The attenuation process for the overdriven detonation wave decaying to a near-CJ state occurs in all tests. After the attenuation process, an unstable detonation wave was observed in most tests. This may be attributed to the increase in the cell width in the attenuation process that exceeds the detonability cell width limit. (author)

  17. Kinetic modeling of propane aromatization reaction over HZSM-5 and GaHZSM-5

    SciTech Connect

    Lukyanov, D.B.; Gnep, N.S.; Guisnet, M.R. . Catalyse en Chimie Organique)

    1995-02-01

    A detailed kinetic model for a propane aromatization reaction over HZSM-5 and GaHZSM-5 is developed. Kinetic modeling results show that propane transformation over HZSM-5 occurs via protolytic cracking and hydrogen transfer routes. The contributions of both routes in propane conversion are established. Rate constants of propane transformation steps are found to be at least 1,000 times lower than the rate constants of diene formation steps, which, in turn, are the slowest among the acid-catalyzed olefin aromatization steps. Gallium introduced into ZSM-5 catalyst is active in dehydrogenation of propane into propene, of olefins into dienes, and of naphthenes into aromatics. At the same time, gallium species catalyze propane transformation into methane and ethene hydrogenation into ethane. Both latter reactions appear to be the main reasons for the limit to aromatics selectivity over GaHZSM-5 catalysts.

  18. Fuel-economy and exhaust-emissions characteristics of diesel vehicles: test results of a prototype Chrysler Volare, 225 CID (3. 7-liter) automobile

    SciTech Connect

    Walter, R.A.

    1982-07-01

    The results obtained from fuel economy and emission tests conducted on a prototype Chrysler Volare diesel vehicle are documented. The vehicle was tested on a chassis dynamometer over selected drive cycles and steady-state conditions. The fuel used, was a DOE/BETC referee fuel. Particulate emission rates were calculated from dilution tunnel measurements and large volume particulate samples were collected for biological and chemical analysis. The vehicle obtained 32.7 mpg for the FTP urban cycle and 48.8 mpg for the highway cycle. The emissions rates were 0.42/1.58/1.17/0.28 g/mile of hydrocarbon, CO, NO/sub x/ and particulates respectively.

  19. Computational modeling of a direct propane fuel cell

    NASA Astrophysics Data System (ADS)

    Khakdaman, H.; Bourgault, Y.; Ternan, M.

    2011-03-01

    The first two dimensional mathematical model of a complete direct propane fuel cell (DPFC) is described. The governing equations were solved using FreeFem software that uses finite element methods. Robin boundary conditions were used to couple the anode, membrane, and cathode sub-domains successfully. The model showed that a polytetrafluoroethylene membrane having its pores filled with zirconium phosphate (ZrP-PTFE), in a DPFC at 150 °C performed much the same as other electrolytes; Nafion, aqueous H3PO4, and H2SO4 doped polybenzimidazole, when they were used in DPFCs. One advantage of a ZrP-PTFE at 150 °C is that it operates without liquid phase water. As a result corrosion will be much less severe and it may be possible for non-precious metal catalysts to be used. Computational results showed that the thickness of the catalyst layer could be increased sufficiently so that the pressure drop between the reactant and product channels of the interdigitated flow fields is small. By increasing the width of the land and therefore the reactant's contact time with the catalyst it was possible to approach 100% propane conversion. Therefore fuel cell operation with a minimum concentration of propane in the product stream should be possible. Finally computations of the electrical potential in the ZrP phase, the electron flux in the Pt/C phase, and the overpotential in both the anode and cathode catalyst layers showed that serious errors in the model occurred because proton diffusion, caused by the proton concentration gradient, was neglected in the equation for the conservation of protons.

  20. Is there a need for dedicated devices?

    PubMed

    Wykrzykowska, Joanna J; Grundeken, Maik J; Stankovic, Goran; Di Mario, Carlo

    2015-01-01

    Although the provisional approach is recommended over a systematic two-stent approach in bifurcation lesions, an a priori two-stent approach may be considered in certain specific anatomies in a minority of cases. Virtual bench test and intravascular imaging studies have provided essential insights into the technical aspects of bifurcation stenting and led to recommendations on how to optimise both the provisional and the two-stent strategies. Dedicated bifurcation stents may further optimise the procedural and clinical outcomes of both strategies. However, randomised data are sparse and more randomised trials are needed to provide evidence as to whether these dedicated devices will indeed improve procedural and clinical outcomes.

  1. Press Site Auditorium dedicated to John Holliman

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA Administrator Daniel S. Goldin hands Mrs. Dianne Holliman a plaque honoring her late husband, John Holliman, a CNN national correspondent. Standing behind Goldin is Center Director Roy Bridges. At right is Tom Johnson, news group chairman of CNN. A ceremony dedicated the KSC Press Site auditorium as the John Holliman Auditorium to honor the correspondent for his enthusiastic, dedicated coverage of America's space program. The auditorium was built in 1980 and has been the focal point for new coverage of Space Shuttle launches. The ceremony followed the 94th launch of a Space Shuttle, on mission STS-96, earlier this morning.

  2. Press Site Auditorium dedicated to John Holliman

    NASA Technical Reports Server (NTRS)

    1999-01-01

    From left, Center Director Roy Bridges and NASA Administrator Daniel S. Goldin applaud as Jay Holliman, with the help of his mother, Mrs. Dianne Holliman, unveils a plaque honoring his father, the late John Holliman. At right is Tom Johnson, news group chairman of CNN. The occasion was the dedication of the KSC Press Site auditorium as the John Holliman Auditorium to honor the CNN national correspondent for his enthusiastic, dedicated coverage of America's space program. The auditorium was built in 1980 and has been the focal point for new coverage of Space Shuttle launches. The ceremony followed the 94th launch of a Space Shuttle, on mission STS-96, earlier this morning.

  3. Supercritical convection, critical heat flux, and coking characteristics of propane

    NASA Technical Reports Server (NTRS)

    Rousar, D. C.; Gross, R. S.; Boyd, W. C.

    1984-01-01

    The heat transfer characteristics of propane at subcritical and supercritical pressure were experimentally evaluated using electrically heated Monel K-500 tubes. A design correlation for supercritical heat transfer coefficient was established using the approach previously applied to supercritical oxygen. Flow oscillations were observed and the onset of these oscillations at supercritical pressures was correlated with wall-to-bulk temperature ratio and velocity. The critical heat flux measured at subcritical pressure was correlated with the product of velocity and subcooling. Long duration tests at fixed heat flux conditions were conducted to evaluate coking on the coolant side tube wall and coking rates comparable to RP-1 were observed.

  4. Dedicated herbaceous biomass feedstock genetics and development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biofuels and bio-based products can be produced from a wide variety of plant feedstocks. To supply enough biomass to meet the proposed need for a bio-based economy a suite of dedicated biomass species must be developed to accommodate a range of growing environments throughout the United States. Re...

  5. 07-NIF Dedication: Jerry McNerney

    ScienceCinema

    Congressman Jerry McNerney

    2016-07-12

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Congressman Jerry McNerney, of California's 11th district, which adjoins Livermore.

  6. 07-NIF Dedication: Jerry McNerney

    SciTech Connect

    Congressman Jerry McNerney

    2009-07-02

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Congressman Jerry McNerney, of California's 11th district, which adjoins Livermore.

  7. 05-NIF Dedication: Tom D'Agostino

    SciTech Connect

    Tom D'Agostino,

    2009-07-02

    The National Ignition Facility, the world's largest laser system, was dedicated at a ceremony on May 29, 2009 at Lawrence Livermore National Laboratory. These are the remarks by Tom D'Agostino, the administrator of the U.S. Department of Energy's National Nuclear Security Administration.

  8. Documentation for propane fleet conversion cost-effectiveness model

    NASA Astrophysics Data System (ADS)

    Taylor, D.; Euritt, M.; Mahmassani, H.

    1992-10-01

    Increased emphasis on energy efficiency and air quality has resulted in a number of state and federal initiatives examining the use of alternative fuels for motor vehicles. Texas instituted an alternative fuels program for public fleet operations beginning in the 1991-92 fiscal year. Life-cycle cost/benefit models for evaluating the economic implications of the action have been developed at the University of Texas at Austin Center for Transportation Research for both compressed natural gas (CNG) and propane. The report documents the various input data, calculations, and assumptions of the Propane Net Present Value (NPV) model. A similar report (number 983-1) documents the same for the CNG model. Input data with constant values across different fleets and locations are discussed first and include basic parameters for on-board storage capacity, vehicle conversion costs, equipment salvage values, etc. Variable input data, reflecting a given fleet size, composition, and location, include the number and types of vehicles, fuel consumption, etc. The next section presents the formulas for the internal model calculations. The final section discusses the basic assumptions underlying the model.

  9. 33 CFR 157.220 - Dedicated clean ballast tanks: Standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Dedicated clean ballast tanks... CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Design and Equipment § 157.220 Dedicated clean ballast tanks: Standards. (a) Cargo tanks that are designated as dedicated clean ballast...

  10. 33 CFR 157.218 - Dedicated clean ballast tanks: Alterations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Dedicated clean ballast tanks... CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.218 Dedicated clean ballast tanks: Alterations. The dedicated clean ballast tanks or equipment on a tank vessel that has...

  11. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor... Dedicated pile drivers. (a) The provisions of subpart CC apply to dedicated pile drivers, except as...) Section 1926.1416(e)(4) (Load weighing and similar devices) applies only to dedicated pile...

  12. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor... Dedicated pile drivers. (a) The provisions of subpart CC apply to dedicated pile drivers, except as...) Section 1926.1416(e)(4) (Load weighing and similar devices) applies only to dedicated pile...

  13. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor... Dedicated pile drivers. (a) The provisions of subpart CC apply to dedicated pile drivers, except as...) Section 1926.1416(e)(4) (Load weighing and similar devices) applies only to dedicated pile...

  14. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor... Dedicated pile drivers. (a) The provisions of subpart CC apply to dedicated pile drivers, except as...) Section 1926.1416(e)(4) (Load weighing and similar devices) applies only to dedicated pile...

  15. 33 CFR 157.218 - Dedicated clean ballast tanks: Alterations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Dedicated clean ballast tanks... CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.218 Dedicated clean ballast tanks: Alterations. The dedicated clean ballast tanks or equipment on a tank vessel that has...

  16. 33 CFR 157.218 - Dedicated clean ballast tanks: Alterations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Dedicated clean ballast tanks... CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.218 Dedicated clean ballast tanks: Alterations. The dedicated clean ballast tanks or equipment on a tank vessel that has...

  17. 33 CFR 157.218 - Dedicated clean ballast tanks: Alterations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Dedicated clean ballast tanks... CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.218 Dedicated clean ballast tanks: Alterations. The dedicated clean ballast tanks or equipment on a tank vessel that has...

  18. 33 CFR 157.218 - Dedicated clean ballast tanks: Alterations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Dedicated clean ballast tanks... CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.218 Dedicated clean ballast tanks: Alterations. The dedicated clean ballast tanks or equipment on a tank vessel that has...

  19. Propane spectral resolution enhancement by the maximum entropy method

    NASA Technical Reports Server (NTRS)

    Bonavito, N. L.; Stewart, K. P.; Hurley, E. J.; Yeh, K. C.; Inguva, R.

    1990-01-01

    The Burg algorithm for maximum entropy power spectral density estimation is applied to a time series of data obtained from a Michelson interferometer and compared with a standard FFT estimate for resolution capability. The propane transmittance spectrum was estimated by use of the FFT with a 2 to the 18th data sample interferogram, giving a maximum unapodized resolution of 0.06/cm. This estimate was then interpolated by zero filling an additional 2 to the 18th points, and the final resolution was taken to be 0.06/cm. Comparison of the maximum entropy method (MEM) estimate with the FFT was made over a 45/cm region of the spectrum for several increasing record lengths of interferogram data beginning at 2 to the 10th. It is found that over this region the MEM estimate with 2 to the 16th data samples is in close agreement with the FFT estimate using 2 to the 18th samples.

  20. Exhaust gas measurements in a propane fueled swirl stabilized combustor

    NASA Technical Reports Server (NTRS)

    Aanad, M. S.

    1982-01-01

    Exhaust gas temperature, velocity, and composition are measured and combustor efficiencies are calculated in a lean premixed swirl stabilized laboratory combustor. The radial profiles of the data between the co- and the counter swirl cases show significant differences. Co-swirl cases show evidence of poor turbulent mixing across the combustor in comparison to the counter-swirl cases. NO sub x levels are low in the combustor but substantial amounts of CO are present. Combustion efficiencies are low and surprisingly constant with varying outer swirl in contradiction to previous results under a slightly different inner swirl condition. This difference in the efficiency trends is expected to be a result of the high sensitivity of the combustor to changes in the inner swirl. Combustor operation is found to be the same for propane and methane fuels. A mechanism is proposed to explain the combustor operation and a few important characteristics determining combustor efficiency are identified.

  1. Chemical kinetic reaction mechanism for the combustion of propane

    NASA Technical Reports Server (NTRS)

    Jachimowski, C. J.

    1984-01-01

    A detailed chemical kinetic reaction mechanism for the combustion of propane is presented and discussed. The mechanism consists of 27 chemical species and 83 elementary chemical reactions. Ignition and combustion data as determined in shock tube studies were used to evaluate the mechanism. Numerical simulation of the shock tube experiments showed that the kinetic behavior predicted by the mechanism for stoichiometric mixtures is in good agrement with the experimental results over the entire temperature range examined (1150-2600K). Sensitivity and theoretical studies carried out using the mechanism revealed that hydrocarbon reactions which are involved in the formation of the HO2 radical and the H2O2 molecule are very important in the mechanism and that the observed nonlinear behavior of ignition delay time with decreasing temperature can be interpreted in terms of the increased importance of the HO2 and H2O2 reactions at the lower temperatures.

  2. [1,3-Bis(diphenylphosphino)propane]trichlorooxorhenium(V).

    PubMed

    Suescun, L; Mombrú, A W; Mariezcurrena, R A; Pardo, H; Russi, S; Kremer, C; Rivero, M; Kremer, E

    2000-08-01

    Trichlorooxo[1,3-propanediylbis(diphenylphosphine)-P,P ']rhenium(V), [ReCl(3)O(C(27)H(26)P(2))], crystallizes with four formula units per unit cell. The crystal structure consists of neutral complexes of [ReOCl(3)(dppp)] [dppp is 1,3-bis(diphenylphosphino)propane] packed by H.pi-ring interactions. The Re atom is octahedrally coordinated to the oxo anion, three Cl atoms and two P atoms from the dppp ligand. The six-membered ring formed by the bidentate dppp ligand and the rhenium metal centre is in a chair conformation. The title compound is an intermediate in the synthesis of bis(dppp) complexes of rhenium.

  3. Propane-1,3-diammonium dichromate(VI).

    PubMed

    Trabelsi, Sonia; Marouani, Houda; Al-Deyab, Salem S; Rzaigui, Mohamed

    2012-08-01

    The title compound, (C(3)H(12)N(2))[Cr(2)O(7)], consists of a discrete dichromate anion with an eclipsed conformation and a propane-1,3-diammonium cation. Both kinds of ions have a mirror plane passing through the bridging O atom and the central methyl-ene C atom of the Cr(2)O(7) (2-) and C(3)H(12)N(2) (2+) moieties, respectively. Anions and cations are alternately stacked to form columns parallel to the b axis. Ions are linked by intra- and inter-column hydrogen bonds of types N-H⋯O and C-H⋯O, involving O atoms of the dichromate anions as acceptors, and ammonium or methyl-ene groups as donors.

  4. Performance of an Experimental Annular Turbojet Combustor with Methane and Propane

    NASA Technical Reports Server (NTRS)

    Norgren, Carl T

    1957-01-01

    Combustion efficiencies obtained with gaseous methane were compared with reported data obtained with gaseous propane for the same experimental combustor configuration. The combustion efficiencies obtained with methane were 98, 91, and 77 percent at simulated flight altitudes of 56,000, 70,000 and 80,000 feet, corresponding to combustor inlet-air pressures from 15 to 5 inches of mercury absolute. Combustion efficiencies with propane were equivalent to those with methane up to a simulated altitude of 70,000 feet. At the most severe conditions investigated propane operated with a higher efficiency and over a wider range of fuel-air ratio than methane.

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

    NASA Technical Reports Server (NTRS)

    Belles, Frank E; Simon, Dorothy M

    1951-01-01

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

  6. Dedicated 3D photoacoustic breast imaging

    PubMed Central

    Kruger, Robert A.; Kuzmiak, Cherie M.; Lam, Richard B.; Reinecke, Daniel R.; Del Rio, Stephen P.; Steed, Doreen

    2013-01-01

    Purpose: To report the design and imaging methodology of a photoacoustic scanner dedicated to imaging hemoglobin distribution throughout a human breast. Methods: The authors developed a dedicated breast photoacoustic mammography (PAM) system using a spherical detector aperture based on our previous photoacoustic tomography scanner. The system uses 512 detectors with rectilinear scanning. The scan shape is a spiral pattern whose radius varies from 24 to 96 mm, thereby allowing a field of view that accommodates a wide range of breast sizes. The authors measured the contrast-to-noise ratio (CNR) using a target comprised of 1-mm dots printed on clear plastic. Each dot absorption coefficient was approximately the same as a 1-mm thickness of whole blood at 756 nm, the output wavelength of the Alexandrite laser used by this imaging system. The target was immersed in varying depths of an 8% solution of stock Liposyn II-20%, which mimics the attenuation of breast tissue (1.1 cm−1). The spatial resolution was measured using a 6 μm-diameter carbon fiber embedded in agar. The breasts of four healthy female volunteers, spanning a range of breast size from a brassiere C cup to a DD cup, were imaged using a 96-mm spiral protocol. Results: The CNR target was clearly visualized to a depth of 53 mm. Spatial resolution, which was estimated from the full width at half-maximum of a profile across the PAM image of a carbon fiber, was 0.42 mm. In the four human volunteers, the vasculature was well visualized throughout the breast tissue, including to the chest wall. Conclusions: CNR, lateral field-of-view and penetration depth of our dedicated PAM scanning system is sufficient to image breasts as large as 1335 mL, which should accommodate up to 90% of the women in the United States. PMID:24320471

  7. The dedicated orthopedic trauma operating room.

    PubMed

    Min, William; Wolinsky, Philip R

    2011-08-01

    The development and implementation of a dedicated orthopedic trauma operating room (OTOR) that is used for the treatment of orthopedic trauma patients has changed and improved the practice of orthopedic trauma surgery. Advantages noted with OTOR implementation include improvements in morbidity and complication rates, enhancements in the professional and personal lifestyles of the on-call surgeon, and increased physician recruitment and retention in orthopedic traumatology. However, the inappropriate use of the OTOR, which can waste valuable resources and delay the treatment of emergent cases, must be monitored and avoided.

  8. Spacelab dedicated discipline laboratory (DDL) utilization concept

    NASA Technical Reports Server (NTRS)

    Wunsch, P.; De Sanctis, C.

    1984-01-01

    The dedicated discipline laboratory (DDL) concept is a new approach for implementing Spacelab missions that involves the grouping of science instruments into mission complements of single or compatible disciplines. These complements are evolved in such a way that the DDL payloads can be left intact between flights. This requires the dedication of flight hardware to specific payloads on a long-term basis and raises the concern that the purchase of additional flight hardware will be required to implement the DDL program. However, the payoff is expected to result in significant savings in mission engineering and assembly effort. A study has been conducted recently to quantify both the requirements for new hardware and the projected mission cost savings. It was found that some incremental additions to the current inventory will be needed to fly the mission model assumed. Cost savings of $2M to 6.5M per mission were projected in areas analyzed in depth, and additional savings may occur in areas for which detailed cost data were not available.

  9. Dedicated breast computed tomography: Basic aspects

    SciTech Connect

    Sarno, Antonio; Mettivier, Giovanni Russo, Paolo

    2015-06-15

    X-ray mammography of the compressed breast is well recognized as the “gold standard” for early detection of breast cancer, but its performance is not ideal. One limitation of screening mammography is tissue superposition, particularly for dense breasts. Since 2001, several research groups in the USA and in the European Union have developed computed tomography (CT) systems with digital detector technology dedicated to x-ray imaging of the uncompressed breast (breast CT or BCT) for breast cancer screening and diagnosis. This CT technology—tracing back to initial studies in the 1970s—allows some of the limitations of mammography to be overcome, keeping the levels of radiation dose to the radiosensitive breast glandular tissue similar to that of two-view mammography for the same breast size and composition. This paper presents an evaluation of the research efforts carried out in the invention, development, and improvement of BCT with dedicated scanners with state-of-the-art technology, including initial steps toward commercialization, after more than a decade of R and D in the laboratory and/or in the clinic. The intended focus here is on the technological/engineering aspects of BCT and on outlining advantages and limitations as reported in the related literature. Prospects for future research in this field are discussed.

  10. Partnering to educate: dedicated education units.

    PubMed

    Dapremont, Jill; Lee, Shirleatha

    2013-09-01

    A current focus of the healthcare industry is centered on addressing the nursing shortage. In the midst of a nursing faculty shortage the Institute of Medicine (2010) recently released a report that calls for increasing the number of baccalaureate prepared nurses to 80% of the workforce by 2020. Therefore, nursing schools are faced with graduating more nurses to meet the demand. Yet, admission to schools of nursing are often limited because of clinical placement sites. The Dedicated Education Unit (DEU) model has been recently introduced to address the challenge of increasing the enrollment of nursing students in spite of a nationwide shortage of nursing faculty. Dedicated Education Units are clinical sites in hospitals where staff nurses serve as preceptors for students in all levels of their nursing education. This model is designed to improve practice education to better prepare students for actual practice while decreasing the number of faculty required at clinical sites. The purpose of this article is to discuss the implications of this model for nursing education, our experience with the DEU model, and issues of deliberation.

  11. State heating oil and propane program: Final report. Survey of No.2 heating oil and propane prices at the retail level, October 1997 through March 1998

    SciTech Connect

    1998-11-01

    The Energy Efficiency Division of the Vermont Department of Public Service (DPS) monitored the price and inventory of residential heating oil and propane during the 1997--98 heating season under a grant from the US Department of Energy`s Energy Information Administration (EIA). DPS staff collected data biweekly between October 5, 1997 and March 16, 1998 on the retail price of {number_sign}2 home heating oil and propane by telephone survey. Propane price quoted was based on the rate for a residential home heating customer using 1,000+ per year. The survey included a sample of fuel dealers selected by the EIA, plus additional dealers and fuels selected by the DPS. The EIA weighted, analyzed, and reported the data collected from their sample.

  12. 33 CFR 157.220 - Dedicated clean ballast tanks: Standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Design and Equipment § 157.220 Dedicated...). (b) Each tank under paragraph (a) of this section must be: (1) A wing tank; or (2) Any other...

  13. 33 CFR 157.220 - Dedicated clean ballast tanks: Standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Design and Equipment § 157.220 Dedicated...). (b) Each tank under paragraph (a) of this section must be: (1) A wing tank; or (2) Any other...

  14. 33 CFR 157.220 - Dedicated clean ballast tanks: Standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Design and Equipment § 157.220 Dedicated...). (b) Each tank under paragraph (a) of this section must be: (1) A wing tank; or (2) Any other...

  15. 33 CFR 157.220 - Dedicated clean ballast tanks: Standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Design and Equipment § 157.220 Dedicated...). (b) Each tank under paragraph (a) of this section must be: (1) A wing tank; or (2) Any other...

  16. 18. Photocopy of drawing of bronze dedication plaque, circa 1903 ...

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

    18. Photocopy of drawing of bronze dedication plaque, circa 1903 (original drawing in possession of City Engineer's Office Grand Rapids, Michigan) DEDICATION PLAQUE. - Bridge Street Bridge, Spanning Grand River, Michigan & Bridge Streets, Grand Rapids, MI

  17. Burning of the Supersonic Propane-Air Mixture in the Aerodynamic Channel With the Stagnant Zone

    DTIC Science & Technology

    2007-11-02

    V.Chernikov, V.Shibkov, O.Surkont. Mechanisms of transversal electric discharge sustention in supersonic air and propane-air flows. -American Institute of Aeronautics and Astronautics, AIAA Paper, 2003, No.03-0872, p. 1 -6 .

  18. Short-Term Energy Outlook Model Documentation: Regional Residential Propane Price Model

    EIA Publications

    2009-01-01

    The regional residential propane price module of the Short-Term Energy Outlook (STEO) model is designed to provide residential retail price forecasts for the 4 Census regions: Northeast, South, Midwest, and West.

  19. PHYSICAL PROPERTIES OF FLUORINATED PROPANE AND BUTANE DERIVATIVES AS ALTERNATIVE REFRIGERANTS

    EPA Science Inventory

    Physical property measurements are presented for 24 fluorinated propane and butane derivatives and one fluorinated ether. These measurements include melting point, boiling point, vapor pressure below the boiling point, heat of vaporization at the boiling point, critical propertie...

  20. School Districts Move to the Head of the Class with Propane

    SciTech Connect

    2016-01-01

    Propane has been a proven fuel for buses for decades. For the first time in 2007, Blue Bird rolled out a propane school bus using direct liquid injection, which was later followed by Thomas Built Buses and Navistar. Because this new technology is much more reliable than previous designs, it is essentially reintroducing propane buses to many school districts. During this same time period, vehicle emissions standards have tightened. To meet them, diesel engine manufacturers have added diesel particulate filters (DPF) and, more recently, selective catalytic reduction (SCR) systems. As an alternative to diesel buses with these systems, many school districts have looked to other affordable, clean alternatives, and they've found that propane fits the bill.

  1. Effect of preprocessing and compressed propane extraction on quality of cilantro (Coriandrum sativum L.).

    PubMed

    Sekhon, Jasreen K; Maness, Niels O; Jones, Carol L

    2015-05-15

    Dehydration leads to quality defects in cilantro such as loss in structure, color, aroma and flavor. Solvent extraction with compressed propane may improve the dehydrated quality. In the present study, effect of drying temperature, particle size, and propane extraction on color, volatile composition, and fatty acid composition of cilantro was evaluated. Cilantro was dehydrated (40°C or 60°C), size reduced and separated into three particles sizes, and extracted with compressed propane at 21-27°C. Major volatile compounds found in dried cilantro were E-2-tetradecenal, dodecanal, E-2-dodecenal, and tetradecanal. Major fatty acids were linoleic acid and α-linolenic acid. Drying at 60°C compared to 40°C resulted in better preservation of color (decrease in browning index values) and volatile compounds. Propane extraction led to a positive change in color values and a decrease in volatile composition, oil content, and fatty acid composition.

  2. Deposit formation in hydrocarbon rocket fuels with an evaluation of a propane heat transfer correlation

    NASA Technical Reports Server (NTRS)

    Masters, P. A.; Aukerman, C. A.

    1982-01-01

    A high pressure fuel coking testing apparatus was designed and developed and was used to evaluate thermal decomposition limits and carbon decomposition rates in heated copper tubes for hydrocarbon fuels. A commercial propane (90% grade) and chemically pure (CP) propane were tested. Heat transfer to supercritical propane was evaluated at 136 atm, bulk fluid velocities of 6 to 30 m/s, and tube wall temperatures in the range of 422 to 811 K. A forced convection heat transfer correlation developed in a previous test effort verified a prediction of most of the experimental data within a + or - 30% range, with good agreement for the CP propane data. No significant differences were apparent in the predictions derived from the correlation when the carbon resistance was included with the film resistance. A post-test scanning electron microprobe analysis indicated occurrences of migration and interdiffusion of copper into the carbon deposit.

  3. School Districts Move to the Head of the Class with Propane

    SciTech Connect

    2016-01-12

    School districts across the country are under pressure to reduce their cost of operations and ensure their budgets are spent wisely. School bus fleets operate more than 675,000 buses in the United States, and many school districts have found the answer to their budget woes in the form of propane, or liquefied petroleum gas (LPG). Propane is a reliable, domestic fuel, and it's used in approximately 2% of school buses nationwide.

  4. 47 CFR 69.125 - Dedicated signalling transport.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Dedicated signalling transport. 69.125 Section... (CONTINUED) ACCESS CHARGES Computation of Charges § 69.125 Dedicated signalling transport. (a) Dedicated signalling transport shall consist of two elements, a signalling link charge and a signalling transfer...

  5. 47 CFR 90.371 - Dedicated short range communications service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Dedicated short range communications service... Regulations Governing the Licensing and Use of Frequencies in the 5850-5925 Mhz Band for Dedicated Short-Range Communications Service (dsrcs) § 90.371 Dedicated short range communications service. (a) These...

  6. 47 CFR 90.371 - Dedicated short range communications service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Dedicated short range communications service... Regulations Governing the Licensing and Use of Frequencies in the 5850-5925 Mhz Band for Dedicated Short-Range Communications Service (dsrcs) § 90.371 Dedicated short range communications service. (a) These...

  7. Measurement of position-specific 13C isotopic composition of propane at the nanomole level

    NASA Astrophysics Data System (ADS)

    Gilbert, Alexis; Yamada, Keita; Suda, Konomi; Ueno, Yuichiro; Yoshida, Naohiro

    2016-03-01

    We have developed a novel method for analyzing intramolecular carbon isotopic distribution of propane as a potential new tracer of its origin. The method is based on on-line pyrolysis of propane followed by analysis of carbon isotope ratios of the pyrolytic products methane, ethylene and ethane. Using propane samples spiked with 13C at the terminal methyl carbon, we characterize the origin of the pyrolytic fragments. We show that the exchange between C-atoms during the pyrolytic process is negligible, and thus that relative intramolecular isotope composition can be calculated. Preliminary data from 3 samples show that site-preference (SP) values, defined as the difference of δ13C values between terminal and sub-terminal C-atom positions of propane, range from -1.8‰ to -12.9‰. In addition, SP value obtained using our method for a thermogenic natural gas sample is consistent with that expected from theoretical models of thermal cracking, suggesting that the isotope fractionation associated with propane pyrolysis is negligible. The method will provide novel insights into the characterization of the origin of propane and will help better understand the biogeochemistry of natural gas deposits.

  8. Dedicated nuclear facilities for electrolytic hydrogen production

    NASA Technical Reports Server (NTRS)

    Foh, S. E.; Escher, W. J. D.; Donakowski, T. D.

    1979-01-01

    An advanced technology, fully dedicated nuclear-electrolytic hydrogen production facility is presented. This plant will produce hydrogen and oxygen only and no electrical power will be generated for off-plant use. The conceptual design was based on hydrogen production to fill a pipeline at 1000 psi and a 3000 MW nuclear base, and the base-line facility nuclear-to-shaftpower and shaftpower-to-electricity subsystems, the water treatment subsystem, electricity-to-hydrogen subsystem, hydrogen compression, efficiency, and hydrogen production cost are discussed. The final conceptual design integrates a 3000 MWth high-temperature gas-cooled reactor operating at 980 C helium reactor-out temperature, direct dc electricity generation via acyclic generators, and high-current density, high-pressure electrolyzers based on the solid polymer electrolyte approach. All subsystems are close-coupled and optimally interfaced and pipeline hydrogen is produced at 1000 psi. Hydrogen costs were about half of the conventional nuclear electrolysis process.

  9. FINESSE: A Dedicated Transiting Exoplanet Spectroscopy Mission

    NASA Astrophysics Data System (ADS)

    Bean, Jacob; FINESSE Science Team

    2017-01-01

    FINESSE (Fast INfrared Exoplanet Spectroscopy Survey Explorer) is a proposed space mission dedicated to performing a statistical census of transiting exoplanet atmospheres. The objectives of FINESSE are to test theories of planetary origins and climate, enable comparative planetology, and open up discovery space on atmospheric chemistry, planetary evolution, and other topics. The baseline design for FINESSE is a 75 cm telescope observing from L2. The FINESSE instrument is a high throughput spectrometer with continuous coverage from 0.5 to 5.0 microns in a single shot. FINESSE will survey on order of 1000 exoplanets with a combination of transmission, dayside emission, and phase-resolved emission spectroscopy during a two year mission. As of this writing FINESSE will be proposed for the NASA Medium-Class Explorers (MIDEX) announcement of opportunity in December 2016. I will present an overview of FINESSE, including the mission concept, science drivers, and expected results from extensive simulations.

  10. Dedicated storage rings for nuclear physics

    SciTech Connect

    Jackson, H.E.

    1984-01-01

    The use of internal targets in circulating beams of electron storage and stretcher rings has been widely discussed recently as a method of achieving high luminosity under conditions of low background, and good energy resolution, with minimal demands for beam from an injecting accelerator. In the two critical areas of the technology, ring design and target development, research is very active, and the prospects for major advances are very bright. Reasonable extrapolations of the current state of the art suggest for many problems in nuclear physics, particularly polarization physics of the nucleon and few body nuclei, internal target measurement may be the optimum experimental technique. This paper, discusses the comparative merit of internal target rings and external beam experiments, reviews briefly current research efforts in the critical areas of the technology, and establishes one goal for the discussions at the workshop. It appears that storage rings dedicated to internal target physics may offer a powerful option for future advances in nuclear physics.

  11. Dedicated heterogeneous node scheduling including backfill scheduling

    DOEpatents

    Wood, Robert R.; Eckert, Philip D.; Hommes, Gregg

    2006-07-25

    A method and system for job backfill scheduling dedicated heterogeneous nodes in a multi-node computing environment. Heterogeneous nodes are grouped into homogeneous node sub-pools. For each sub-pool, a free node schedule (FNS) is created so that the number of to chart the free nodes over time. For each prioritized job, using the FNS of sub-pools having nodes useable by a particular job, to determine the earliest time range (ETR) capable of running the job. Once determined for a particular job, scheduling the job to run in that ETR. If the ETR determined for a lower priority job (LPJ) has a start time earlier than a higher priority job (HPJ), then the LPJ is scheduled in that ETR if it would not disturb the anticipated start times of any HPJ previously scheduled for a future time. Thus, efficient utilization and throughput of such computing environments may be increased by utilizing resources otherwise remaining idle.

  12. Spectroscopic studies of cryogenic fluids: Benzene in propane

    NASA Astrophysics Data System (ADS)

    Nowak, R.; Bernstein, E. R.

    1987-03-01

    Energy shifts and bandwidths for the 1B2u↔1A1g optical absorption and emission transitions of benzene dissolved in propane are presented as a function of pressure, temperature, and density. Both absorption and emission spectra exhibit shifts to lower energy as a function of density, whereas no shifts are observed if density is kept constant and temperature and pressure are varied simultaneously. Density is thus the fundamental microscopic parameter for energy shifts of optical transitions. The emission half-width is a linear function of both temperature and pressure but the absorption half-width is dependent only upon pressure. These results are interpreted qualitatively in terms of changes occurring in the intermolecular potentials of the ground and excited states. Both changes in shape of and separation between the ground and excited state potentials are considered as a function of density. Classical dielectric (Onsager-Böttcher), microscopic dielectric (Wertheim) and microscopic quantum statistical mechanical (Schweizer-Chandler) theories of solvent effects on solute electronic spectra are compared with the experimental results. Calculations suggest limited applicability of dielectric theories but good agreement between experiment and microscopic theory. The results demonstrate the usefulness of cryogenic solutions for high pressure, low temperature spectroscopic studies of liquids.

  13. Assessment of the risk of transporting propane by truck and train

    SciTech Connect

    Geffen, C.A.

    1980-03-01

    The risk of shipping propane is discussed and the risk assessment methodology is summarized. The risk assessment model has been constructed as a series of separate analysis steps to allow the risk to be readily reevaluated as additional data becomes available or as postulated system characteristics change. The transportation system and accident environment, the responses of the shipping system to forces in transportation accidents, and release sequences are evaluated to determine both the likelihood and possible consequences of a release. Supportive data and analyses are given in the appendices. The risk assessment results are related to the year 1985 to allow a comparison with other reports in this series. Based on the information presented, accidents involving tank truck shipments of propane will be expected to occur at a rate of 320 every year; accidents involving bobtails would be expected at a rate of 250 every year. Train accidents involving propane shipments would be expected to occur at a rate of about 60 every year. A release of any amount of material from propane trucks, under both normal transportation and transport accident conditions, is to be expected at a rate of about 110 per year. Releases from propane rail tank cars would occur about 40 times a year. However, only those releases that occur during a transportation accident or involve a major tank defect will include sufficient propane to present the potential for danger to the public. These significant releases can be expected at the lower rate of about fourteen events per year for truck transport and about one event every two years for rail tank car transport. The estimated number of public fatalities resulting from these significant releases in 1985 is fifteen. About eleven fatalities per year result from tank truck operation, and approximately half a death per year stems from the movement of propane in rail tank cars.

  14. Lean and ultralean stretched propane-air counterflow flames

    SciTech Connect

    Cheng, Zhongxian; Pitz, Robert W.; Wehrmeyer, Joseph A.

    2006-06-15

    Stretched laminar flame structures for a wide range of C{sub 3}H{sub 8}-air mixtures vs hot products are investigated by laser-based diagnostics and numerical simulation. The hot products are produced by a lean H{sub 2}-air premixed flame. The effect of stretch rate and equivalence ratio on four groups of C{sub 3}H{sub 8}-air flame structures is studied in detail by Raman scattering measurements and by numerical calculations of the major species concentration and temperature profiles. The equivalence ratio, f, is varied from a near-stoichiometric condition (f=0.86) to the sublean limit (f=0.44) and the stretch rate varies from 90 s{sup -1} to near extinction. For most of these C{sub 3}H{sub 8}-air lean mixtures, hot products are needed to maintain the flame. The significant feature of these flames is the relatively low flame temperatures (1200-1800 K). For this temperature range, the predicted C{sub 3}H{sub 8}-air flame structure is sensitive to the specific chemical kinetic mechanism. Two types of flame structures (a lean self-propagating flame and a lean diffusion-controlled flame) are obtained based on the combined effect of stretch and equivalence ratio. Three different mechanisms, the M5 mechanism, the Optimized mechanism, and the San Diego mechanism, are chosen for the numerical simulations. None of the propane chemical mechanisms give good agreement with the data over the entire range of flame conditions. (author)

  15. Dedicated PET scanners for breast imaging.

    PubMed

    Freifelder, R; Karp, J S

    1997-12-01

    We have used computer simulations to compare two designs for a PET scanner dedicated to breast imaging with a whole-body PET scanner. The new designs combine high spatial resolution, high sensitivity, and good energy resolution to detect small, low-contrast masses. The detectors are position sensitive NaI(Tl) scintillators. The first design is a ring scanner surrounding the breast and the second consists of two planar detectors placed on opposite sides of the breast. We have employed standard performance measures to compare the different designs: contrast, percentage standard deviation of the background, and signal-to-noise ratios of reconstructed images. The results of the simulations show that both of the proposed designs have better lesion detectability than a whole-body scanner. The results also show that contrast is higher in the ring breast system but that the noise is lower in the planar breast system. Overall, the ring system yields images with the best signal-to-noise ratios, although the planar system offers practical advantages for imaging the breast and axilla.

  16. Dedicated PET scanners for breast imaging

    NASA Astrophysics Data System (ADS)

    Freifelder, Richard; Karp, Joel S.

    1997-12-01

    We have used computer simulations to compare two designs for a PET scanner dedicated to breast imaging with a whole-body PET scanner. The new designs combine high spatial resolution, high sensitivity, and good energy resolution to detect small, low-contrast masses. The detectors are position sensitive NaI(Tl) scintillators. The first design is a ring scanner surrounding the breast and the second consists of two planar detectors placed on opposite sides of the breast. We have employed standard performance measures to compare the different designs: contrast, percentage standard deviation of the background, and signal-to-noise ratios of reconstructed images. The results of the simulations show that both of the proposed designs have better lesion detectability than a whole-body scanner. The results also show that contrast is higher in the ring breast system but that the noise is lower in the planar breast system. Overall, the ring system yields images with the best signal-to-noise ratios, although the planar system offers practical advantages for imaging the breast and axilla.

  17. Divergent Metabolic Pathways for Propane and Propionate Utilization by a Soil Isolate1

    PubMed Central

    Vestal, J. R.; Perry, Jerome J.

    1969-01-01

    The metabolism of propane and propionate by a soil isolate (Brevibacterium sp. strain JOB5) was investigated. The presence of isocitrate lyase in cells grown on isopropanol, acetate, or propane and the absence of this inducible enzyme in n-propanol- and propionate-grown cells suggested that propane is not metabolized via C-terminal oxidation. Methylmalonyl coenzyme A mutase and malate synthase are constitutive in this organism. The incorporation of 14CO2 into pyruvate accumulated during propionate utilization suggests that propionate is metabolized via the methyl-malonyl-succinate pathway. These results were further substantiated by radiorespirometric studies with propionate-1-14C, -2-14C, and -3-14C as substrate. Propane -2-14C was shown, by unlabeled competitor experiments, to be oxidized to acetone; acetone and isopropanol are oxidized in this organism to acetol. Cleavage of acetol to acetate and CO2 would yield the inducer for the isocitrate lyase present in propane-grown cells. PMID:5802607

  18. State Heating Oil & Propane Program. Final report 1997/98 heating season

    SciTech Connect

    Hunton, G.

    1998-06-01

    The following is a summary report of the New Hampshire Governor`s Office of Energy and Community Services (ECS) participation in the State Heating Oil and Propane Program (SHOPP) for the 1997/98 heating season. SHOPP is a cooperative effort, linking energy offices in East Coast and Midwest states, with the Department of Energy (DOE), Energy Information Administration (EIA) for the purpose of collecting retail price data for heating oil and propane. The program is funded by the participating state with a matching grant from DOE. SHOPP was initiated in response to congressional inquires into supply difficulties and price spikes of heating oil and propane associated with the winter of 1989/90. This is important to New Hampshire because heating oil controls over 55% of the residential heating market statewide. Propane controls 10% of the heating market statewide and is widely used for water heating and cooking in areas of the state where natural gas is not available. Lower installation cost, convenience, lower operating costs compared to electricity, and its perception as a clean heating fuel have all worked to increase the popularity of propane in New Hampshire and should continue to do so in the future. Any disruption in supply of these heating fuels to New Hampshire could cause prices to skyrocket and leave many residents in the cold.

  19. Epoxidation of Short-Chain Alkenes by Resting-Cell Suspensions of Propane-Grown Bacteria

    PubMed Central

    Hou, Ching T.; Patel, Ramesh; Laskin, Allen I.; Barnabe, Nancy; Barist, Irene

    1983-01-01

    Sixteen new cultures of propane-utilizing bacteria were isolated from lake water from Warinanco Park, Linden, N.J. and from lake and soil samples from Bayway Refinery, Linden, N.J. In addition, 19 known cultures obtained from culture collections were also found to be able to grow on propane as the sole carbon and energy source. In addition to their ability to oxidize n-alkanes, resting-cell suspensions of both new cultures and known cultures grown on propane oxidize short-chain alkenes to their corresponding 1,2-epoxides. Among the substrate alkenes, propylene was oxidized at the highest rate. In contrast to the case with methylotrophic bacteria, the product epoxides are further metabolized. Propane and other gaseous n-alkanes inhibit the epoxidation of propylene. The optimum conditions for in vivo epoxidation are described. Results from inhibition studies indicate that a propane monooxygenase system catalyzes both the epoxidation and hydroxylation reactions. Experiments with cell-free extracts show that both hydroxylation and epoxidation activities are located in the soluble fraction obtained after 80,000 × g centrifugation. PMID:16346338

  20. Heteroepitaxially grown zeolitic imidazolate framework membranes with unprecedented propylene/propane separation performances.

    PubMed

    Kwon, Hyuk Taek; Jeong, Hae-Kwon; Lee, Albert S; An, He Seong; Lee, Jong Suk

    2015-09-30

    Propylene/propane separation is one of the most challenging separations, currently achieved by energy-intensive cryogenic distillation. Despite the great potential for energy-efficient membrane-based separations, no commercial membranes are currently available due to the limitations of current polymeric materials. Zeolitic imidazolate framework, ZIF-8, with the effective aperture size of ∼4.0 Å, has been shown to be very promising for propylene/propane separation. Despite the extensive research on ZIF-8 membranes, only a few reported ZIF-8 membranes have displayed good propylene/propane separation performances presumably due to the challenges of controlling the microstructures of polycrystalline membranes. Here we report the first well-intergrown membranes of ZIF-67 (Co-substituted ZIF-8) by heteroepitaxially growing ZIF-67 on ZIF-8 seed layers. The ZIF-67 membranes exhibited impressively high propylene/propane separation capabilities. Furthermore, when a tertiary growth of ZIF-8 layers was applied to heteroepitaxially grown ZIF-67 membranes, the membranes exhibited unprecedentedly high propylene/propane separation factors of ∼200 possibly due to enhanced grain boundary structure.

  1. No. 2 heating oil/propane program 1994--1995. Final report

    SciTech Connect

    McBrien, J.

    1995-05-01

    During the 1994--95 heating season, the Massachusetts Division of Energy Resources (DOER) participated in a joint data collection program between several state energy offices and the federal Department of Energy`s (DOE) Energy Information Administration (EIA). The purpose of the program was to collect and monitor retail and wholesale heating oil and propane prices and inventories from October 1994 through March 1995. This program augmented the existing Massachusetts data collection system and served several important functions. The information helped the federal and state governments respond to consumer, congressional and media inquiries regarding No. 2 oil and propane. The information also provided policy decision-makers with timely, accurate and consistent data to monitor current heating oil and propane markets and develop appropriate state responses when necessary. In addition, the communication network between states and the DOE was strengthened through this program. This final report begins with an overview of the unique events that had an impact on the petroleum markets prior to and during the reporting period. Next, the report summarizes the results from residential heating oil and propane price surveys conducted by DOER over the 1994--95 heating season. The report also incorporates the wholesale heating oil and propane prices and inventories collected by EIA and distributed to the states. Finally, the report outlines DOER`s use of the data.

  2. Any Way to Run a Railroad: Implications of Dedicated Trains

    SciTech Connect

    Dilger, F.C.; Halstead, R. J.

    2006-07-01

    The DOE recently issued a policy statement that it would use dedicated trains for most waste shipments to Yucca Mountain. Prior uncertainty about use of dedicated trains for Yucca Mountain rail shipments prevented an assessment of the likely impacts. This paper examines the controversy over the use of dedicated trains and evaluates the national impacts of shipping waste to Yucca Mountain using dedicated trains on the Union Pacific's preferred rail system. The national impacts of the routing are reported as route miles through three land use types: Rural, Urban and Census Places. (authors)

  3. Enthalpies and entropies of vaporization of propan-2-ol-2-methylpropan-1-ol solutions

    NASA Astrophysics Data System (ADS)

    Baev, A. A.; Baev, A. K.

    2014-03-01

    P-T-x dependences are measured for the solutions of a propan-2-ol-2-methylpropan-1-ol binary system and the enthalpies and entropies of vaporization are determined. Dimerization in propan-2-ol and 2-methylpropan-1-ol is rationalized and the contribution from energy introduced by isostructural methyl groups to the enthalpy of vaporization is determined. Structural and energy analyses of solutions with networks of specific interactions are performed. The formation of heterodimers in solutions and vapors with reduced hydrogen bond energies and specific interactions with the 2 s 2(C) unshared electron pairs of the carbon atoms of terminal methyl groups in ethyl and propyl fragments of propan-2-ol and 2-methylpropan-1-ol, respectively, is substantiated. The hydrogen bond energy of heterodimers is estimated.

  4. Concentration of mechanical pulp mill effluents and NaCl solutions through propane hydrate formation

    SciTech Connect

    Ngan, Y.T.; Englezos, P.

    1996-06-01

    In this work, recovery of water from mechanical pulp mill effluents and 2.5 wt% NaCl solutions through propane hydrate formation was investigated. A new apparatus in which hydrate nucleation, growth, separation, and melting occur in one vessel was designed and built. The emphasis of the work was on crystal separation. The average reduction in the salt content of the recovered water from the NaCl solutions was found to be 31%. Displacement with propane could increase the amount of recovered water at the same purity level. Further improvement in the purity could be accomplished with washing with water. The results with the effluents showed that the total organic carbon and the salt content of the recovered water were lower by 23 and 26%, respectively, from the levels in the effluent. Improved separation could be achieved by displacement with liquid propane.

  5. Explosive-driven shock wave and vortex ring interaction with a propane flame

    NASA Astrophysics Data System (ADS)

    Giannuzzi, P. M.; Hargather, M. J.; Doig, G. C.

    2016-11-01

    Experiments were performed to analyze the interaction of an explosively driven shock wave and a propane flame. A 30 g explosive charge was detonated at one end of a 3-m-long, 0.6-m-diameter shock tube to produce a shock wave which propagated into the atmosphere. A propane flame source was positioned at various locations outside of the shock tube to investigate the effect of different strength shock waves. High-speed retroreflective shadowgraph imaging visualized the shock wave motion and flame response, while a synchronized color camera imaged the flame directly. The explosively driven shock tube was shown to produce a repeatable shock wave and vortex ring. Digital streak images show the shock wave and vortex ring propagation and expansion. The shadowgrams show that the shock wave extinguishes the propane flame by pushing it off of the fuel source. Even a weak shock wave was found to be capable of extinguishing the flame.

  6. Design and Operation of the Synthesis Gas Generator System for Reformed Propane and Glycerin Combustion

    NASA Astrophysics Data System (ADS)

    Pickett, Derek Kyle

    Due to an increased interest in sustainable energy, biodiesel has become much more widely used in the last several years. Glycerin, one major waste component in biodiesel production, can be converted into a hydrogen rich synthesis gas to be used in an engine generator to recover energy from the biodiesel production process. This thesis contains information detailing the production, testing, and analysis of a unique synthesis generator rig at the University of Kansas. Chapter 2 gives a complete background of all major components, as well as how they are operated. In addition to component descriptions, methods for operating the system on pure propane, reformed propane, reformed glycerin along with the methodology of data acquisition is described. This chapter will serve as a complete operating manual for future students to continue research on the project. Chapter 3 details the literature review that was completed to better understand fuel reforming of propane and glycerin. This chapter also describes the numerical model produced to estimate the species produced during reformation activities. The model was applied to propane reformation in a proof of concept and calibration test before moving to glycerin reformation and its subsequent combustion. Chapter 4 first describes the efforts to apply the numerical model to glycerin using the calibration tools from propane reformation. It then discusses catalytic material preparation and glycerin reformation tests. Gas chromatography analysis of the reformer effluent was completed to compare to theoretical values from the numerical model. Finally, combustion of reformed glycerin was completed for power generation. Tests were completed to compare emissions from syngas combustion and propane combustion.

  7. Toxicological investigation of liquid petroleum gas explosion: human model for propane/ethyl mercaptan exposures.

    PubMed

    Lowry, W T; Gamse, B; Armstrong, A T; Corn, J M; Juarez, L; McDowell, J L; Owens, R

    1991-03-01

    Four individuals died as the result of a propane explosion. As with many propane explosions, the question was raised as to the adequacy of the product's odorization after the autopsy studies had been conducted. In most cases, this question leads to litigation. Ethyl mercaptan is a widely used odorant for propane and was used in this instance. Three of the four victims had blood available at autopsy for study. Quantitative analyses of the victims' blood, obtained during autopsy, were performed using gas chromatography/mass spectrometry, without subjecting the samples to hydrolysis. These analyses determined the relative amounts of propane and ethyl mercaptan in the blood to be 90, 63, and 175 mL/m3 headspace, and 0.36, 0.34, and 0.77 microgram/L blood, respectively. Since mercaptans have been reported in human blood as products of metabolism, modeling studies were conducted to establish the validity of the autopsy data and to develop an autopsy toxicology protocol for investigating explosion deaths. When subjects were not exposed to an atmosphere containing ethyl mercaptan, dimethylsulfide was the only mercaptan detectable in their blood without severe hydrolysis prior to analysis. Metabolic ethyl mercaptan is sufficiently bound to be undetectable by the methods used without hydrolysis. Human subjects were exposed to a flammable mixture of air and propane odorized with ethyl mercaptan. The analyses of the blood from these subjects produced results which were comparable with those for the explosion victims, establishing that the question of odorant adequacy can be addressed at the autopsy of propane explosion victims. It is extremely important that the pathologist and toxicologist investigating gas explosion deaths recognize the valuable evidence existing in the victim's blood.

  8. 41 CFR 102-74.280 - Are privately owned vehicles converted for propane carburetion permitted in underground parking...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... vehicles converted for propane carburetion permitted in underground parking facilities? 102-74.280 Section... underground parking facilities? Federal agencies must not permit privately owned vehicles converted for propane carburetion to enter underground parking facilities unless the owner provides to the...

  9. 41 CFR 102-74.280 - Are privately owned vehicles converted for propane carburetion permitted in underground parking...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... vehicles converted for propane carburetion permitted in underground parking facilities? 102-74.280 Section... underground parking facilities? Federal agencies must not permit privately owned vehicles converted for propane carburetion to enter underground parking facilities unless the owner provides to the...

  10. 47 CFR 69.125 - Dedicated signalling transport.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) ACCESS CHARGES Computation of Charges § 69.125 Dedicated signalling transport. (a) Dedicated signalling transport shall consist of two elements, a signalling link charge and a signalling transfer point (STP) port termination charge. (b)(1) A flat-rated signalling link charge expressed in dollars...

  11. Metabolism of Propane, n-Propylamine, and Propionate by Hydrocarbon-Utilizing Bacteria1

    PubMed Central

    Blevins, W. T.; Perry, J. J.

    1972-01-01

    Studies were conducted on the oxidation and assimilation of various three-carbon compounds by a gram-positive rod isolated from soil and designated strain R-22. This organism can utilize propane, propionate, or n-propylamine as sole source of carbon and energy. Respiration rates, enzyme assays, and 14CO2 incorporation experiments suggest that propane is metabolized via methyl ketone formation; propionate and n-propylamine are metabolized via the methylmalonyl-succinate pathway. Isocitrate lyase activity was found in cells grown on acetate and was not present in cells grown on propionate or n-propylamine. 14CO2 was incorporated into pyruvate when propionate and n-propylamine were oxidized in the presence of NaAsO2, but insignificant radioactivity was found in pyruvate produced during the oxidation of propane and acetone. The n-propylamine dissimilatory mechanism was inducible in strain R-22, and amine dehydrogenase activity was detected in cells grown on n-propylamine. Radiorespirometer and 14CO2 incorporation studies with several propane-utilizing organisms indicate that the methylmalonyl-succinate pathway is the predominant one for the metabolism of propionate. PMID:16559164

  12. Performance and emissions of a catalytic reactor with propane, diesel, and Jet A fuels

    NASA Technical Reports Server (NTRS)

    Anderson, D. N.

    1977-01-01

    Tests were made to determine the performance and emissions of a catalytic reactor operated with propane, No. 2 diesel, and Jet A fuels. A 12-cm diameter and 16-cm long catalytic reactor using a proprietary noble metal catalyst was operated at an inlet temperature of 800 K, a pressure of 300,000 Pa and reference velocities of 10 to 15 m/s. No significant differences between the performance of the three fuels were observed when 98.5 percent purity propane was used. The combustion efficiency for 99.8-percent purity propane tested later was significantly lower, however. The diesel fuel contained 135 ppm of bound nitrogen and consequently produced the highest NOx emissions of the three fuels. As much as 85 percent of the bound nitrogen was converted to NOx. Steady-state emissions goals based on half the most stringent proposed automotive standards were met when the reactor was operated at an adiabatic combustion temperature higher than 1350 K with all fuels except the 99.8-percent purity propane. With that fuel, a minimum temperature of 1480 K was required.

  13. Synthesis and characterization of energetic salts based on the new propan-2-ylidene methanetriamium cations

    NASA Astrophysics Data System (ADS)

    Zhang, Tao; Liu, Long; Li, Chunshan; Zhang, Yanqiang; Li, Zengxi; Zhang, Suojiang

    2014-06-01

    Development of new hypergolic ionic liquids is the key in replacing toxic N,N-dimethylhydrazine as green liquids propellants. Three salts based on the new propan-2-ylidene methanetriamium cations and dicyanamide anion were synthesized and characterized by 1H and 13C NMR, IR and Raman spectroscopy, elemental analysis, and TG/DTA. In addition, their crystal structures were determined by X-ray single crystal diffraction. N-(propan-2-ylidene) methanetriamium dicyanamide (1) crystallizes in the monoclinic space group P21/n, N,N‧-bi(propan-2-ylidene) methanetriamium dicyanamide (2) in triclinic P - 1, and N,N‧,N″-tri(propan-2-ylidene) methanetriamium dicyanamide (3) in monoclinic C2/c. With heats of formation (from 1.56 to 1.80 kJ g-1) and densities (from 1.19 to 1.31 g cm-3) in hand, the detonation pressure (P) and velocity (D), and specific impulse (Isp) values of salts were calculated as 8.94 GPa, 4989 m s-1 and 174.3 s (1), 7.91 GPa, 4815 m s-1 and 179.0 s (2), and 7.33 GPa, 4693 m s-1 and 180.6 s (3), respectively. Impact sensitivities of 1, 2 and 3 were measured to be no less than 40 J by hammer tests, which places these salts in the insensitive class. Moreover, the resulting salts are hypergolic with white fuming nitric acid and exhibit potential as bipropellants.

  14. 40 CFR 721.10360 - 1-Substituted propane, 3-(triethoxysilyl)-, reaction products with polyethylene glycol mono...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-(triethoxysilyl)-, reaction products with polyethylene glycol mono-(branched tridecyl) ether (generic). 721.10360... Substances § 721.10360 1-Substituted propane, 3-(triethoxysilyl)-, reaction products with polyethylene glycol...)-, reaction products with polyethylene glycol mono-(branched tridecyl) ether (PMN P-09-628) is subject...

  15. 40 CFR 721.10360 - 1-Substituted propane, 3-(triethoxysilyl)-, reaction products with polyethylene glycol mono...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-(triethoxysilyl)-, reaction products with polyethylene glycol mono-(branched tridecyl) ether (generic). 721.10360... Substances § 721.10360 1-Substituted propane, 3-(triethoxysilyl)-, reaction products with polyethylene glycol...)-, reaction products with polyethylene glycol mono-(branched tridecyl) ether (PMN P-09-628) is subject...

  16. 40 CFR 721.10360 - 1-Substituted propane, 3-(triethoxysilyl)-, reaction products with polyethylene glycol mono...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-(triethoxysilyl)-, reaction products with polyethylene glycol mono-(branched tridecyl) ether (generic). 721.10360... Substances § 721.10360 1-Substituted propane, 3-(triethoxysilyl)-, reaction products with polyethylene glycol...)-, reaction products with polyethylene glycol mono-(branched tridecyl) ether (PMN P-09-628) is subject...

  17. A Theoretical Study of the Methyl and Aldehyde Torsion FIR Spectra in Symmetric Propanal Isotopomers

    NASA Astrophysics Data System (ADS)

    Smeyers, Y. G.; Villa, M.; Uc, V. H.; Vivier-Bunge, A.

    2000-05-01

    This paper is an extension of the techniques developed by us [A. Vivier-Bunge, V. H. Uc, and Y. G. Smeyers, J. Chem. Phys. 109, 2279 (1998)] for standard propanal. In that paper the potential energy surface for the simultaneous methyl and asymmetric aldehydic torsions was calculated at RHF/MP2 level using the 6-311(3df,p) basis set for propanal. The fit of the energy values to symmetry-adapted functional forms was carried out by using the 28 energy values which retain the C3 dynamical symmetry of the methyl group in the optimization procedure. With this potential, as well as with the kinetic parameters and the electric dipole moment variations, the FIR frequencies and intensities for the methyl and aldehyde torsions of seven symmetric isotopomers of propanal were determined theoretically using two-dimensional calculations. The calculated spectra of propanal and three of its isotopomers were compared with the available experimental data. It is found that the calculations for the cis conformer satisfactorily reproduce the aldehyde and methyl torsion spectra and furnish also methyl torsionally excited progressions for the aldehyde torsion modes. The methyl torsion frequencies agree especially well whenever the methyl group is nondeuterated. The small deviations encountered for the deuterated compound are probably due to some mass effect, such as the zero-point vibrational energy correction, which is not taken into account in the present calculations. Finally, the influence of the deuteration on the intensities is discussed.

  18. Surface Termination of M1 Phase and Rational Design of Propane Ammoxidation Catalysts

    SciTech Connect

    Guliants, Vadim

    2015-02-16

    This final report describes major accomplishments in this research project which has demonstrated that the M1 phase is the only crystalline phase required for propane ammoxidation to acrylonitrile and that a surface monolayer terminating the ab planes of the M1 phase is responsible for their activity and selectivity in this reaction. Fundamental studies of the topmost surface chemistry and mechanism of propane ammoxidation over the Mo-V-(Te,Sb)-(Nb,Ta)-O M1 and M2 phases resulted in the development of quantitative understanding of the surface molecular structure – reactivity relationships for this unique catalytic system. These oxides possess unique catalytic properties among mixed metal oxides, because they selectively catalyze three alkane transformation reactions, namely propane ammoxidation to acrylonitrile, propane oxidation to acrylic acid and ethane oxidative dehydrogenation, all of considerable economic significance. Therefore, the larger goal of this research was to expand this catalysis to other alkanes of commercial interest, and more broadly, demonstrate successful approaches to rational design of improved catalysts that can be applied to other selective (amm)oxidation processes.

  19. RETENTION OF HALOCARBONS ON A HEXAFLUOROPROPYLENE EPOXIDE-MODIFIED GRAPHITIZED CARBON BLACK - IV. PROPANE- BASED COMPOUNDS

    EPA Science Inventory

    The retention characteristics of 25 propane-based bromofluorocarbon, chlorocarbon, chlorofluorocarbon, and fluorocarbon fluids have been studied as a function of temperature on a stationary phase consisting of a 5% (m/m) coating of a low-molecular-mass polymer of hexafluoropropyl...

  20. Analysis of U.S. Propane Markets Winter 1996-97, An

    EIA Publications

    1997-01-01

    This study constitutes an examination of propane supply, demand, and price developments and trends. The Energy Information Administration's approach focused on identifying the underlying reasons for the tight supply/demand balance in the fall of 1996, and on examining the potential for a recurrence of these events next year.

  1. Zinc-substituted ZIF-67 nanocrystals and polycrystalline membranes for propylene/propane separation.

    PubMed

    Wang, Chongqing; Yang, Fan; Sheng, Luqian; Yu, Jian; Yao, Kexin; Zhang, Lixiong; Pan, Yichang

    2016-10-18

    Continuous ZIF-67 polycrystalline membranes with effective propylene/propane separation performances were successfully fabricated through the incorporation of zinc ions into the ZIF-67 framework. The separation factor increases from 1.4 for the pure ZIF-67 membrane to 50.5 for the 90% zinc-substituted ZIF-67 membrane.

  2. 16 CFR Figure 7 to Part 1633 - Elements of Propane Flow Control for Each Burner

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Elements of Propane Flow Control for Each Burner 7 Figure 7 to Part 1633 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE FLAMMABILITY (OPEN FLAME) OF MATTRESS SETS Pt. 1633, Fig. 7 Figure...

  3. 16 CFR Figure 7 to Part 1633 - Elements of Propane Flow Control for Each Burner

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Elements of Propane Flow Control for Each Burner 7 Figure 7 to Part 1633 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE FLAMMABILITY (OPEN FLAME) OF MATTRESS SETS Pt.1633, Fig. 7 Figure...

  4. 16 CFR Figure 7 to Part 1633 - Elements of Propane Flow Control for Each Burner

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Elements of Propane Flow Control for Each Burner 7 Figure 7 to Part 1633 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE FLAMMABILITY (OPEN FLAME) OF MATTRESS SETS Pt.1633, Fig. 7 Figure...

  5. 16 CFR Figure 7 to Part 1633 - Elements of Propane Flow Control for Each Burner

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Elements of Propane Flow Control for Each Burner 7 Figure 7 to Part 1633 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE FLAMMABILITY (OPEN FLAME) OF MATTRESS SETS Pt. 1633, Fig. 7 Figure...

  6. 16 CFR Figure 7 to Part 1633 - Elements of Propane Flow Control for Each Burner

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Elements of Propane Flow Control for Each Burner 7 Figure 7 to Part 1633 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE FLAMMABILITY (OPEN FLAME) OF MATTRESS SETS Pt.1633, Fig. 7 Figure...

  7. 40 CFR 1065.341 - CVS and batch sampler verification (propane check).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications Flow-Related... from the piping configuration upstream of the flow meter adversely affect the flow measurement. (7... measurements and CVS flow rate measurements with the reference value. (c) Prepare for the propane check...

  8. 40 CFR 1065.341 - CVS, PFD, and batch sampler verification (propane check).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications Flow... from the piping configuration upstream of the flow meter adversely affect the flow measurement. (7... measurements and CVS flow rate measurements with the reference value. (c) Prepare for the propane check...

  9. 40 CFR 1065.341 - CVS and batch sampler verification (propane check).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications Flow-Related... from the piping configuration upstream of the flow meter adversely affect the flow measurement. (7... measurements and CVS flow rate measurements with the reference value. (c) Prepare for the propane check...

  10. THE HEAT CAPACITY OF FLUORINATED PROPANE AND BUTANE DERIVATIVES BY DIFFERENTIAL SCANNING CALORIMETRY

    EPA Science Inventory

    The paper gives results of the measurement (to 3% accuracy) of the constant-pressure liquid-phase heat capacities of 21 hydrogen-containing fluorinated propane and butane derivatives and one fluorinated ether (CF3OCF2H) with boiling points ranging from -34.6 to 76.7 C, using diff...

  11. Developing synthesis techniques for zeolitic-imidazolate framework membranes for high resolution propylene/propane separation

    NASA Astrophysics Data System (ADS)

    Kwon, Hyuk Taek

    Propylene/propane separation is one of the most challenging separations, currently achieved by energy-intensive cryogenic distillation. Despite the great potentials for energy-efficient membrane-based propylene/propane separation processes, no commercial membranes are available due to the limitations (i.e., low selectivity) of current polymeric materials. Zeolitic imidazolate frameworks (ZIFs) are promising membrane materials primarily due to their well-defined ultra-micropores with controllable surface chemistry along with their relatively high thermal/chemical stabilities. In particular, ZIF-8 with the effective aperture size of ~ 4.0 A has been shown very promising for propylene/propane separation. Despite the extensive research on ZIF-8 membranes, only a few of ZIF-8 membranes have displayed good propylene/propane separation performances presumably due to the challenges of controlling the microstructures of polycrystalline membranes. Since the membrane microstructures are greatly influenced by processing techniques, it is critically important to develop new techniques. In this dissertation, three state-of-the-art ZIF membrane synthesis techniques are developed. The first is a one-step in-situ synthesis technique based on the concept of counter diffusion. The technique enabled us to obtain highly propylene selective ZIF-8 membranes in less than a couple of hours with exceptional mechanical strength. Most importantly, due to the nature of the counter-diffusion concept, the new method offered unique opportunities such as healing defective membranes (i.e., poorly-intergrown) as well as significantly reducing the consumption of costly ligands and organic solvents. The second is a microwave-assisted seeding technique. Using this new seeding technique, we were able to prepare seeded supports with a high packing density in a couple of minutes, which subsequently grown into highly propylene-selective ZIF-8 membranes with an average propylene/propane selectivity of ~40

  12. Novel Pt/Mg(In)(Al)O catalysts for ethane and propane dehydrogenation

    SciTech Connect

    Sun, Pingping; Siddiqi, Georges; Vining, William C.; Chi, Miaofang; Bell, Alexis T.

    2011-10-28

    Catalysts for the dehydrogenation of light alkanes were prepared by dispersing Pt on the surface of a calcined hydrotalcite-like support containing indium, Mg(In)(Al)O. Upon reduction in H{sub 2} at temperatures above 673 K, bimetallic particles of PtIn are observed by TEM, which have an average diameter of 1 nm. Analysis of Pt LIII-edge extended X-ray absorption fine structure (EXAFS) data shows that the In content of the bimetallic particles increases with increasing bulk In/Pt ratio and reduction temperature. Pt LIII-edge X-ray absorption near edge structure (XANES) indicates that an increasing donation of electronic charge from In to Pt occurs with increasing In content in the PtIn particles. The activity and selectivity of the Pt/Mg(In)(Al)O catalysts for ethane and propane dehydrogenation reactions are strongly dependent on the bulk In/Pt ratio. For both reactants, maximum activity was achieved for a bulk In/Pt ratio of 0.48, and at this In/Pt ratio, the selectivity to alkene was nearly 100%. Coke deposition was observed after catalyst use for either ethane or propane dehydrogenation, and it was observed that the alloying of Pt with In greatly reduced the amount of coke deposited. Characterization of the deposit by Raman spectroscopy indicates that the coke is present as highly disordered graphite particles <30 nm in diameter. While the amount of coke deposited during ethane and propane dehydrogenation are comparable, the effects on activity are dependent on reactant composition. Coke deposition had no effect on ethane dehydrogenation activity, but caused a loss in propane dehydrogenation activity. This difference is attributed to the greater ease with which coke produced on the surface of PtIn nanoparticles migrates to the support during ethane dehydrogenation versus propane dehydrogenation.

  13. Editorial: A dedication to Professor Jan Evetts

    NASA Astrophysics Data System (ADS)

    Weber, Harald; Dew-Hughes, David; Campbell, Archie; Barber, Zoe; Somekh, Rob; Glowacki, Bartek

    2006-03-01

    A few days before the beginning of the 7th European Conference on Applied Superconductivity we learned that Professor Jan Evetts, a pioneer of superconductor research, a brilliant scientist, a wonderful person and a great personal friend, had passed away. We therefore decided to dedicate the 7th European Conference on Applied Superconductivity to the memory of Jan Evetts. The following citation is based on material provided by his former supervisor (D Dew-Hughes) and his closest co-workers in Cambridge. Professor Jan Edgar Evetts (1939-2005) Professor Jan Edgar Evetts (1939-2005) Jan Evetts passed away after losing his second battle with cancer on 24th August 2005. He made an outstanding series of contributions to the science of superconductivity and to the understanding of superconducting materials and was an indefatigable champion of the development of applications of superconductivity. The loss to the superconductivity community is incalculable, as attested by the many communications received from colleagues throughout the world. Jan was born on 31 March 1939, and attended the Dragon School in Oxford, and later Haileybury. He was awarded an exhibition to read Natural Sciences at Pembroke College, Cambridge. He entered the college in 1958 and took his BA degree in 1961. He then undertook a Certificate of Postgraduate Study in Physics under the supervision of Professor Neville Mott. He was the first student to undertake this newly-instituted course; the title of his thesis was `The Resistance of Transition Metals'. In 1962 he joined David Dew-Hughes' superconducting materials research group, along with Archie Campbell and Anant Narlikar. In fact it was Jan's enthusiasm for the proposed course of research that helped convince David that he should follow Professor Alan Cottrell's suggestion to apply metallurgical methodology to the study of the factors that controlled critical current density in the type II superconductors that were then under development for

  14. Elevation view of dedication plaque on east wall of south ...

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

    Elevation view of dedication plaque on east wall of south lobby - National Home for Disabled Volunteer Soldiers, Pacific Branch, Main Mental Health Building, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA

  15. Comparison of combustion characteristics of ASTM A-1, propane, and natural-gas fuels in an annular turbojet combustor

    NASA Technical Reports Server (NTRS)

    Wear, J. D.; Jones, R. E.

    1973-01-01

    The performance of an annular turbojet combustor using natural-gas fuel is compared with that obtained using ASTM A-1 and propane fuels. Propane gas was used to simulate operation with vaporized kerosene fuels. The results obtained at severe operating conditions and altitude relight conditions show that natural gas is inferior to both ASTM A-1 and propane fuels. Combustion efficiencies were significantly lower and combustor pressures for relight were higher with natural-gas fuel than with the other fuels. The inferior performance of natural gas is shown to be caused by the chemical stability of the methane molecule.

  16. Propane respiration jump-starts microbial response to a deep oil spill.

    PubMed

    Valentine, David L; Kessler, John D; Redmond, Molly C; Mendes, Stephanie D; Heintz, Monica B; Farwell, Christopher; Hu, Lei; Kinnaman, Franklin S; Yvon-Lewis, Shari; Du, Mengran; Chan, Eric W; Garcia Tigreros, Fenix; Villanueva, Christie J

    2010-10-08

    The Deepwater Horizon event resulted in suspension of oil in the Gulf of Mexico water column because the leakage occurred at great depth. The distribution and fate of other abundant hydrocarbon constituents, such as natural gases, are also important in determining the impact of the leakage but are not yet well understood. From 11 to 21 June 2010, we investigated dissolved hydrocarbon gases at depth using chemical and isotopic surveys and on-site biodegradation studies. Propane and ethane were the primary drivers of microbial respiration, accounting for up to 70% of the observed oxygen depletion in fresh plumes. Propane and ethane trapped in the deep water may therefore promote rapid hydrocarbon respiration by low-diversity bacterial blooms, priming bacterial populations for degradation of other hydrocarbons in the aging plume.

  17. [Fire disaster due to deflagration of a propane gas-air mixture].

    PubMed

    Nadjem, Hadi; Vogt, Susanne; Simon, Karl-Heinz; Pollak, Stefan; Geisenberger, Dorothee; Kramer, Lena; Pircher, Rebecca; Perdekampl, Markus Große; Thierauf-Emberger, Annette

    2015-01-01

    On 26 Nov 2012, a serious fire occurred at Neustadt/Black Forest in which 14 persons in a sheltered workshop died and 10 other individuals were injured. The fire was caused by the unbridled escape of propane gas due to accidental disconnection of the screw fixing between a gas bottle and a catalytic heater. Deflagration of the propane gas-air mixture set the workshop facilities on fire. In spite of partly extensive burns the fatally injured victims could be rapidly identified. The results of the fire investigations at the scene and the autopsy findings are presented. Carboxyhemoglobin concentrations ranged between 8 and 56 % and signs of fire fume inhalation were present in all cases. Three victims had eardrum ruptures due to the sudden increase in air pressure during the deflagration.

  18. Observation of propane cluster size distributions during nucleation and growth in a Laval expansion

    NASA Astrophysics Data System (ADS)

    Ferreiro, Jorge J.; Chakrabarty, Satrajit; Schläppi, Bernhard; Signorell, Ruth

    2016-12-01

    We report on molecular-level studies of the condensation of propane gas and propane/ethane gas mixtures in the uniform (constant pressure and temperature) postnozzle flow of Laval expansions using soft single-photon ionization by vacuum ultraviolet light and mass spectrometric detection. The whole process, from the nucleation to the growth to molecular aggregates of sizes of several nanometers (˜5 nm), can be monitored at the molecular level with high time-resolution (˜3 μs) for a broad range of pressures and temperatures. For each time, pressure, and temperature, a whole mass spectrum is recorded, which allows one to determine the critical cluster size range for nucleation as well as the kinetics and mechanisms of cluster-size specific growth. The detailed information about the size, composition, and population of individual molecular clusters upon condensation provides unique experimental data for comparison with future molecular-level simulations.

  19. Hydrogen Safety Issues Compared to Safety Issues with Methane andPropane

    SciTech Connect

    Green, Michael A.

    2005-08-20

    The hydrogen economy is not possible if the safety standards currently applied to liquid hydrogen and hydrogen gas by many laboratories are applied to devices that use either liquid or gaseous hydrogen. Methane and propane are commonly used by ordinary people without the special training. This report asks, 'How is hydrogen different from flammable gasses that are commonly being used all over the world?' This report compares the properties of hydrogen, methane and propane and how these properties may relate to safety when they are used in both the liquid and gaseous state. Through such an analysis, sensible safety standards for the large-scale (or even small-scale) use of liquid and gaseous hydrogen systems can be developed. This paper is meant to promote discussion of issues related to hydrogen safety so that engineers designing equipment can factor sensible safety standards into their designs.

  20. Thermophysical properties of propane from 85 to 700/sup 0/K at pressures to 70 MPa

    SciTech Connect

    Goodwin, R.D.; Haynes, W.M.

    1982-04-01

    Thermophysical properties of propane are tabulated at integral temperatures over the entire range of fluid states from 85 to 700/sup 0/K along isobars to 70 MPa by using a modified form of the nonanalytic equation of state. These tables, along with a table for the saturated liquid, include values for density, compressibility factor, internal energy, enthalpy, entropy, heat capacities, fugacity, sound velocity, dielectric constant, and isochore and isotherm derivatives. In addition to the equation of state, equations are presented for vapor pressures, orthobaric vapor and liquid densities, ideal gas properties, virial coefficients, dielectric constants, heats of vaporization, melting C, and orthobaric liquid specific heats, enthalpies, and entropies. Coefficients were determined by a least squares fit of selected experimental data, including several new sets of data not included in previous propane correlations. Comparisons between experimental and calculated values are given, including those for sound velocities, heat capacities, P-rho-T data, etc.

  1. Dedicated biomass crops can enhance biodiversity in the arable landscape.

    PubMed

    Haughton, Alison J; Bohan, David A; Clark, Suzanne J; Mallott, Mark D; Mallott, Victoria; Sage, Rufus; Karp, Angela

    2016-11-01

    Suggestions that novel, non-food, dedicated biomass crops used to produce bioenergy may provide opportunities to diversify and reinstate biodiversity in intensively managed farmland have not yet been fully tested at the landscape scale. Using two of the largest, currently available landscape-scale biodiversity data sets from arable and biomass bioenergy crops, we take a taxonomic and functional trait approach to quantify and contrast the consequences for biodiversity indicators of adopting dedicated biomass crops on land previously cultivated under annual, rotational arable cropping. The abundance and community compositions of biodiversity indicators in fields of break and cereal crops changed when planted with the dedicated biomass crops, miscanthus and short rotation coppiced (SRC) willow. Weed biomass was consistently greater in the two dedicated biomass crops than in cereals, and invertebrate abundance was similarly consistently higher than in break crops. Using canonical variates analysis, we identified distinct plant and invertebrate taxa and trait-based communities in miscanthus and SRC willows, whereas break and cereal crops tended to form a single, composite community. Seedbanks were shown to reflect the longer term effects of crop management. Our study suggests that miscanthus and SRC willows, and the management associated with perennial cropping, would support significant amounts of biodiversity when compared with annual arable crops. We recommend the strategic planting of these perennial, dedicated biomass crops in arable farmland to increase landscape heterogeneity and enhance ecosystem function, and simultaneously work towards striking a balance between energy and food security.

  2. Outcomes following a dedicated period of research during surgical training.

    PubMed

    Stutchfield, B M; Harrison, E M; Wigmore, S J; Parks, R W; Garden, O J

    2011-11-01

    With recent 'working-time'-related changes to surgical training structure, the value of dedicated research during surgical training has been questioned. Online survey examining career and academic outcomes following a period of surgically related dedicated research at a Scottish University between 1972 and 2007. Of 58 individuals identified, contact details were available for 49 and 43 (88%) responded. Ninety-five percent (n = 41) of respondents continue to pursue a career in surgery and 41% (n = 17) are currently in academic positions. Ninety-one percent (n = 39) had published one or more first-author peer-reviewed articles directly related to their research, with 53% (n = 23) publishing three or more. Respondents with a clinical component to their research published significantly more papers than those with purely laboratory-based research (P = 0.04). Eighty-one percent (n = 35) thought that research was necessary for career progression, but only 42% (n = 18) felt research should be integral to training. In conclusion, the majority of surgical trainees completing a dedicated research period, published papers and continued to pursue a surgical career with a research interest. A period of dedicated research was thought necessary for career progression, but few thought dedicated research should be integral to surgical training.

  3. Electrochemical promotion of propane oxidation on Pt deposited on a dense β"-Al2O3 ceramic Ag+ conductor

    NASA Astrophysics Data System (ADS)

    Tsampas, Michail; Kambolis, Anastasios; Obeid, Emil; Lizarraga, Leonardo; Sapountzi, Foteini; Vernoux, Philippe

    2013-08-01

    A new kind of electrochemical catalyst based on a Pt porous catalyst film deposited on a β"-Al2O3 ceramic Ag+ conductor was developed and evaluated during propane oxidation. It was observed that upon anodic polarization, the rate of propane combustion was significantly electropromoted up to 400%. Moreover, for the first time, exponential increase of the catalytic rate was evidenced during galvanostatic transient experiment in excellent agreement with EPOC equation.

  4. Analysis of the site-specific carbon isotope composition of propane by gas source isotope ratio mass spectrometer

    NASA Astrophysics Data System (ADS)

    Piasecki, Alison; Sessions, Alex; Lawson, Michael; Ferreira, A. A.; Neto, E. V. Santos; Eiler, John M.

    2016-09-01

    Site-specific isotope ratio measurements potentially provide valuable information about the formation and degradation of complex molecules-information that is lost in conventional bulk isotopic measurements. Here we discuss the background and possible applications of such measurements, and present a technique for studying the site-specific carbon isotope composition of propane at natural abundance based on mass spectrometric analysis of the intact propane molecule and its fragment ions. We demonstrate the feasibility of this approach through measurements of mixtures of natural propane and propane synthesized with site-specific 13C enrichment, and we document the limits of precision of our technique. We show that mass balance calculations of the bulk δ13C of propane based on our site-specific measurements is generally consistent with independent constraints on bulk δ13C. We further demonstrate the accuracy of the technique, and illustrate one of its simpler applications by documenting the site-specific carbon isotope signature associated with gas phase diffusion of propane, confirming that our measurements conform to the predictions of the kinetic theory of gases. This method can be applied to propane samples of moderate size (tens of micromoles) isolated from natural gases. Thus, it provides a means of studying the site-specific stable isotope systematics of propane at natural isotope abundances on sample sizes that are readily recovered from many natural environments. This method may also serve as a model for future techniques that apply high-resolution mass spectrometry to study the site-specific isotopic distributions of larger organic molecules, with potential applications to biosynthesis, forensics and other geochemical subjects.

  5. Catalytic ozonation of propanal using wood fly ash and metal oxide nanoparticle impregnated carbon.

    PubMed

    Kastner, James R; Ganagavaram, Rangan; Kolar, Praveen; Teja, Amyn; Xu, Chunbao

    2008-01-15

    Catalytic ozonation of propanal at ambient temperatures (23-25 degrees C) was investigated by varying propanal and ozone concentrations and catalyst type. The catalysts tested included wood fly ash (WFA), magnetically separated ash, synthetic hematite and magnetite, and metal oxide nanoparticle impregnated activated carbon and peanut hull char. A power law model independent of ozone concentration for WFA (r(w), moles g(-1) s(-1)) and magnetite (r(m)) were, respectively, r(w) = k'(w) C(R(0.89)) and r(m) = k'(m)C(R(1.55)), where kw, and k'(m) were 2.36 x 10(-6) g(-1) s(-1) (moles)(-0.11) (m3)(0.89) and 6.5 x 10(-4) g(-1) s(-1) (moles)(-0.55) (m3)(1.55), respectively (5-15 ppmv). Magnetite and hematite present in the WFA were theorized to be the primary active sites, since magnetically separated WFA had a significantly higher reaction rate (approximately 12x, mol m(-2) s(-1)) than that of WFA. X-ray diffraction analysis demonstrated a qualitative increase in magnetite and hematite in the magnetically separated ash, and synthetic magnetite and hematite had reaction rates >80x and 200x that of WFA or activated carbon (surface area basis). Supercritical deposition of hematite on/in peanut hull char successfully generated a porous, pelleted catalystfrom an agricultural residue capable of oxidizing propanal at rates 12x activated carbon and similar to commercially available catalysts (per mass basis). Water vapor significantly increased the propanal reaction rate when using wood fly ash and activated carbon.

  6. Update from the Analysis of High Resolution Propane Spectra and the Interpretation of Titan's Infrared Spectra

    NASA Astrophysics Data System (ADS)

    Klavans, V.; Nixon, C.; Hewagama, T.; Jennings, D. E.

    2012-04-01

    Titan has an extremely thick atmosphere dominated by nitrogen, but includes a range of trace species such as hydrocarbons and nitriles. One such hydrocarbon is propane (C3H8). Propane has 21 active IR bands covering broad regions of the mid-infrared. Therefore, its ubiquitous signature may potentially mask weaker signatures of other undetected species with important roles in Titan's chemistry. Cassini's Composite Infrared Spectrometer (CIRS) observations of Titan's atmosphere hint at the presence of such molecules. Unfortunately, C3H8 line atlases for the vibration bands ν8, ν21, ν20, and ν7 (869, 922, 1054, and 1157 cm-1, respectively) are not currently available for subtracting the C3H8 signal to reveal, or constrain, the signature of underlying chemical species. Using spectra previously obtained by Jennings, D. E., et al. at the McMath-Pierce FTIR at Kitt Peak, AZ, as the source and automated analysis utilities developed for this application, we are compiling an atlas of spectroscopic parameters for propane that characterize the ro-vibrational transitions in the above bands. In this paper, we will discuss our efforts for inspecting and fitting the aforementioned bands, present updated results for spectroscopic parameters including absolute line intensities and transition frequencies in HITRAN and GEISA formats, and show how these optical constants will be used in searching for other trace chemical species in Titan's atmosphere. Our line atlas for the ν21 band contains a total number of 2971 lines. The band integrated strength calculated for the ν21 band is 1.003 cm-1/(cm-atm). Fig. 1: Demonstration of Gaussian fit for sample spectral region 927.25 to 927.50 cm-1 (ν21). References: Jennings, D. E., et al.: "Foreign-gas pressure broadening parameters of propane near 748 cm-1". JQSRT, Vol. 42, pp. 399-403, 1989.

  7. Analysis of Ignition Behavior in a Turbocharged Direct Injection Dual Fuel Engine Using Propane and Methane as Primary Fuels

    SciTech Connect

    Polk, A. C.; Gibson, C. M.; Shoemaker, N. T.; Srinivasan, K. K.; Krishnan, S. R.

    2013-05-24

    This paper presents experimental analyses of the ignition delay (ID) behavior for diesel-ignited propane and diesel-ignited methane dual fuel combustion. Two sets of experiments were performed at a constant speed (1800 rev/min) using a 4-cylinder direct injection diesel engine with the stock ECU and a wastegated turbocharger. First, the effects of fuel-air equivalence ratios (© pilot ¼ 0.2-0.6 and © overall ¼ 0.2-0.9) on IDs were quantified. Second, the effects of gaseous fuel percent energy substitution (PES) and brake mean effective pressure (BMEP) (from 2.5 to 10 bar) on IDs were investigated. With constant © pilot (> 0.5), increasing © overall with propane initially decreased ID but eventually led to premature propane autoignition; however, the corresponding effects with methane were relatively minor. Cyclic variations in the start of combustion (SOC) increased with increasing © overall (at constant © pilot), more significantly for propane than for methane. With increasing PES at constant BMEP, the ID showed a nonlinear (initially increasing and later decreasing) trend at low BMEPs for propane but a linearly decreasing trend at high BMEPs. For methane, increasing PES only increased IDs at all BMEPs. At low BMEPs, increasing PES led to significantly higher cyclic SOC variations and SOC advancement for both propane and methane. Finally, the engine ignition delay (EID) was also shown to be a useful metric to understand the influence of ID on dual fuel combustion.

  8. Michigan residential heating oil and propane price survey: 1995--1996 heating season. Final report

    SciTech Connect

    Moriarty, C.

    1996-05-01

    This report summarizes the results of a survey of residential No. 2 distillate fuel (home heating oil) and liquefied petroleum gas (propane) prices over the 1995--1996 heating season in Michigan. The Michigan`s Public Service Commission (MPSC) conducted the survey under a cooperative agreement with the US Department of Energy`s (DOE) Energy Information Administration (EIA). This survey was funded in part by a grant from the DOE. From October 1995 through March 1996, the MPSC surveyed participating distributors by telephone for current residential retail home heating oil and propane prices. The MPSC transmitted the data via a computer modem to the EIA using the Petroleum Electronic Data Reporting Option (PEDRO). Survey results were published in aggregate on the MPSC World Wide Web site at http://ermisweb.state.mi.us/shopp. The page was updated with both residential and wholesale prices immediately following the transmission of the data to the EIA. The EIA constructed the survey using a sample of Michigan home heating oil and propane retailers. The sample accounts for different sales volumes, geographic location, and sources of primary supply.

  9. Theoretical Investigation of the Gas-Phase Reaction of CrO(+) with Propane.

    PubMed

    Beck, Jennifer E; Dudley, Timothy J

    2017-03-02

    Transition metal oxide cations (e.g., MO(+)) have been shown to oxidize small alkanes in the gas phase. The chromium oxide cation is of particular interest because it is more reactive than oxides of earlier transition metals but is more selective than oxides of later transition metals. The reaction of CrO(+) with propane has been shown to produce a number of products: propanol, propene, ethene, and hydrogen. Few theoretical studies exist for reactions of simple transition metal oxide cations with larger alkanes. We have analyzed the potential energy surfaces associated with the reaction of CrO(+) with propane using two DFT methods, B3LYP and M06-L. Energetically viable reaction paths leading to each experimentally observed product have been characterized. Each reaction path begins with formation of a reactive intermediate in which either an α- or β-hydrogen from propane is extracted by the oxygen atom of CrO(+). While pathways leading to formation of hydrogen and ethene were found to occur on a single spin surface, energetically viable pathways to forming propanol and propene require a transition from the quartet spin surface to the sextet surface. The minimum-energy crossing points between the quartet and sextet surfaces were found to be well below the energy level of the reactants and structurally resemble the initial reactive intermediates.

  10. Thermocatalytic Destruction of Gas-Phase Perchloroethylene Using Propane as a Hydrogen Source

    PubMed Central

    Willinger, Marty; Rupp, Erik; Barbaris, Brian; Gao, Song; Arnolda, Robert; Betterton, Eric; Sáez, A. Eduardo

    2009-01-01

    The use of propane in combination with oxygen to promote the destruction of perchloroethylene (PCE) over a platinum (Pt)/rhodium (Rh) catalyst on a cerium/zirconium oxide washcoat supported on an alumina monolith was explored. Conversions of PCE were measured in a continuous flow reactor with residence times less than 0.5 s and temperatures ranging from 200 to 600°C. The presence of propane was shown to increase significantly the conversion of PCE over oxygen-only conditions. Conversions close to 100% were observed at temperatures lower than 450°C with 20% oxygen and 2% propane in the feed, which makes this process attractive from a practical standpoint. In the absence of oxygen, PCE conversion is even higher, but the catalyst suffers significant deactivation in less than an hour. Even though results show that oxygen competes with reactants for active sites on the catalyst, the long-term stability that oxygen confers to the catalyst makes the process an efficient alternative to PCE oxidation. A Langmuir-Hinshelwood competitive adsorption model is proposed to quantify PCE conversion. PMID:19217713

  11. Kinetics of Hydrogen Oxidation Downstream of Lean Propane and Hydrogen Flames

    NASA Technical Reports Server (NTRS)

    Fine, Burton

    1961-01-01

    The decay of hydrogen was measured downstream of lean, flat, premixed hydrogen and propane-air flames seated on cooled porous burners. Experimental variables included temperature, pressure, initial equivalence ratio and diluent. Sampling of burned gas was done through uncooled quartz orifice probes, and the analysis was based on gas chromatography. An approximate treatment of the data in which diffusion was neglected led to the following rate expression for the zone downstream of hydrogen flames d[H (sub 2)] divided by (d times t) equals 1.7 times 10 (sup 10) [H (sub 2)] (sup 3) divided by (sub 2) [O (sub 2)]e (sup (-8100 divided by RT)) moles per liters per second. On the basis of a rate expression of this form, the specific rate constant for the reaction downstream of hydrogen flames was about three times as great as that determined downstream of propane flames. This result was explained on the basis of the existence of a steady state between hydrogen and carbon monoxide in the burned gas downstream of propane flames.

  12. Cometabolic biodegradation of 1,2,3-trichloropropane by propane-oxidizing bacteria.

    PubMed

    Wang, Baixin; Chu, Kung-Hui

    2017-02-01

    1,2,3-Trichloropropane (TCP) is an emerging groundwater pollutant and suspected human carcinogen. TCP, a recalcitrant contaminant, has been detected in the subsurface near TCP manufacture facilities and many superfund sites. Considering the toxicity and the occurence of TCP, there is a need to seek for cost-effective treatment technologies for TCP-contaminated sites. This paper investigated TCP biodegradation by propane-oxidizing bacteria (PrOB) which are known to express propane monooxygenase (PrMO). PrMO can cometabolically degrade many different contaminants. Four PrOB, Rhodococus jostii RHA1, Mycobacterium vaccae JOB5, Rhodococcus rubber ENV425 and one isolate Sphingopyxis sp. AX-A were examined for their ability to degrade TCP. All the four PrOB resting cells were able to degrade TCP. Strain JOB5 exhibited the best TCP degradation ability (vinitial = 9.7 ± 0.7 μg TCP (mg protein)(-1)h(-1)). No TCP was degraded in the presence of acetylene (an inhibitor for PrMO), suggesting that PrMO might be responsible for TCP degradation. Furthermore, competitive inhibition was observed between propane and TCP, and between trichloroethylene (TCE) and TCP.

  13. Propanal synthesis from aqueous propylene glycol/hydrogen peroxide on a Ru/alumina catalyst

    SciTech Connect

    Disselkamp, Robert S.; Harris, Benjamin D.; Patel, Jayshribe N.; Hart, Todd R.; Peden, Charles HF

    2008-05-01

    The conversion of polyol materials, including 1,2-diols, into higher commodity chemicals is actively being pursued by many researchers. Here we report the production of propanal from propylene glycol and hydrogen peroxide using a Ru/alumina catalyst. Experiments were conducted by adding up to four peroxide equivalents under steady-state reflux conditions at 371 K. The product propanal and its subsequent reaction product with substrate, 1,3-dioxolane-2-ethyl-4-methyl, was observed to be an intermediate achieving a maximum concentration of 3% of substrate. Buffering using Mg(OH)2 at pH~10 resulted in propanal formation, whereas buffering at similar pH using Na2HSO4 did not, from which we propose that magnesium acts as a promoter in the reaction. The mechanism appears to be a dehydration to enol, followed by rearrangement to product. Experiments utilizing Ru/carbon did not yield any propanol suggesting that the acidic sites of alumina aid the dehydration reaction. To our knowledge, this represents the first time hydrogen peroxide has been used in an alcohol dehydration reaction.

  14. Sorption of methane, ethane, propane, butane, carbon dioxide, and nitrogen on kerogen

    NASA Astrophysics Data System (ADS)

    Pribylov, A. A.; Skibitskaya, N. A.; Zekel', L. A.

    2014-06-01

    Sorption isotherms of nitrogen, methane (in the pressure range of 0.1-40 MPa), ethane (0.1-3.7MPa), propane (0.01-1 MPa), butane (0.01-0.2 MPa), and carbon dioxide (0.1-6 MPa) are measured on two adsorbents with kerogen contents of 16 and 75% at temperatures of 303, 323, 343 K. Adsorption volumes are calculated for all adsorption systems using two independent methods. The BET technique is used to determine the surface area values of the two adsorbents on the basis of sorption data for ethane, propane, butane, and carbon dioxide. The initial and isosteric adheat of sorption values are calculated on the basis of sorption isotherms of ethane, propane, butane, carbon dioxide measured at three temperatures. It is found from comparing the dependences of isosteric heat of sorption on the two adsorbents that molecules of the above gases diffuse into its bulk (adsorbent 2) in addition to sorbing on the outside surface formed by kerogen molecules, while sorption of the same gases on the rock (adsorbent 1) is similar to sorption on a smooth hard adsorbent surface.

  15. 47 CFR 90.371 - Dedicated short range communications service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Dedicated short range communications service. 90.371 Section 90.371 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Intelligent Transportation Systems Radio...

  16. Dedication: Hugh Daubeny, Berry Breeder and Enthusiast Extraordinaire

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript presents a short biography of Dr. Hugh Daubeny, now emeritus geneticist from Agriculture and Agri-Food Canada. This biography is being published as a dedication chapter for a book on raspberry breeding, an activity that Dr. Daubeny pursued for his 45-year career. Hugh has released 15...

  17. [Advanced online search techniques and dedicated search engines for physicians].

    PubMed

    Nahum, Yoav

    2008-02-01

    In recent years search engines have become an essential tool in the work of physicians. This article will review advanced search techniques from the world of information specialists, as well as some advanced search engine operators that may help physicians improve their online search capabilities, and maximize the yield of their searches. This article also reviews popular dedicated scientific and biomedical literature search engines.

  18. Are You Dedicated to Diversity? Is the Welcome Mat Out?

    ERIC Educational Resources Information Center

    Hrabe, Frank

    2006-01-01

    American colleges and universities often refer to their "dedication to diversity". The truth is, some institutions really make an effort, and some only offer lip service. This article discusses ways on how college institutions can provide a more welcoming atmosphere to gay, lesbian, bisexual, and transgendered (glbt) students through use…

  19. 42. From Superintendent's Monthly Report, March 1935. DEDICATION OF HALEAKALA ...

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

    42. From Superintendent's Monthly Report, March 1935. DEDICATION OF HALEAKALA HIGHWAY, FEBRUARY 23, 1935. A ONE-HOUR RADIO BROADCAST BY KGU IN HONOLULU WAS TRANSMITTED FROM THE SUMMIT CEREMONIES TO ISLANDERS THROUGHOUT THE TERRITORY - Haleakala National Park Roads, Pukalani, Maui County, HI

  20. A study of the xenon effect in type-II clathrate hydrate synthesis; Commencing with hydrogen, argon and xenon uptake into a propane clathrate hydrate

    NASA Astrophysics Data System (ADS)

    Abbondondola, Joanne Angela

    It has been proposed that clathrate hydrates can be a possible storage medium for alternative fuels, such as hydrogen. The type-II propane gas hydrate is a viable choice because there are twice as many small cages as large cages and the small cavities are available for hydrogen storage. However, propane hydrate formation is a kinetically slow process which makes it commercially unattractive. Our objectives were twofold; (1) to quantify hydrogen, argon and xenon sorption into a preformed type-II propane hydrate at near-ambient conditions and (2) to investigate the effect of xenon on the rate of type-II propane hydrate formation. The propane hydrate is synthesized from 250 mum ice grains, and is estimated to have a porosity of 65 %. Hydrogen is rapidly absorbed by the hydrate sample and approaches the equilibrium vapor pressure in an hour before a very slow residual absorption process ensues. For an initial hydrogen pressure of 1.5 MPa, about 4.5 % of the available 512 cages are occupied by hydrogen after one hour, and 4.9 % after 18 hours. In contrast, for both argon and xenon significantly more gas is absorbed by the hydrate, but at a much slower rate: about 5% as fast for xenon and 1% as fast for argon. We conclude that hydrogen readily diffuses through the propane hydrate microcrystal structure, while argon and xenon are probably absorbed by growing new double hydrate while consuming the propane hydrate. Thus, although considerably higher pressures would be required to store significant quantities of hydrogen in propane hydrate, it appears that the crystal can be loaded and emptied in relatively short amounts of time. Experimental results show that propane is incorporated into clathrate hydrate cages more rapidly using propane-xenon mixtures than for pure propane gas. For a 0.92 xenon: propane mix, 60% of the theoretical yield of propane enclathration is achieved in 20 minutes, versus several days for pure propane. It appears that xenon serves to nucleate the

  1. 33 CFR 157.224 - Dedicated Clean Ballast Tanks Operations Manual.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Dedicated Clean Ballast Tanks... VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Design and Equipment § 157.224 Dedicated Clean Ballast Tanks Operations Manual. Each Dedicated Clean Ballast Tanks Operations Manual...

  2. 33 CFR 157.212 - Dedicated Clean Ballast Tanks Operations Manual: Not approved.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Dedicated Clean Ballast Tanks... RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.212 Dedicated Clean Ballast Tanks Operations Manual: Not approved. If the Dedicated Clean...

  3. 33 CFR 157.225 - Dedicated clean ballast tanks operations: General.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Dedicated clean ballast tanks... VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Dedicated Clean Ballast Tanks Operations § 157.225 Dedicated clean ballast tanks operations: General. The master of a tank vessel...

  4. 33 CFR 157.226 - Dedicated Clean Ballast Tanks Operations Manual: Procedures to be followed.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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  5. 33 CFR 157.225 - Dedicated clean ballast tanks operations: General.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

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  6. 33 CFR 157.212 - Dedicated Clean Ballast Tanks Operations Manual: Not approved.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Dedicated Clean Ballast Tanks... RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.212 Dedicated Clean Ballast Tanks Operations Manual: Not approved. If the Dedicated Clean...

  7. 33 CFR 157.224 - Dedicated Clean Ballast Tanks Operations Manual.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Dedicated Clean Ballast Tanks... VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Design and Equipment § 157.224 Dedicated Clean Ballast Tanks Operations Manual. Each Dedicated Clean Ballast Tanks Operations Manual...

  8. 33 CFR 157.224 - Dedicated Clean Ballast Tanks Operations Manual.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Dedicated Clean Ballast Tanks... VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Design and Equipment § 157.224 Dedicated Clean Ballast Tanks Operations Manual. Each Dedicated Clean Ballast Tanks Operations Manual...

  9. 33 CFR 157.226 - Dedicated Clean Ballast Tanks Operations Manual: Procedures to be followed.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Dedicated Clean Ballast Tanks... ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Dedicated Clean Ballast Tanks Operations § 157.226 Dedicated Clean Ballast Tanks Operations...

  10. 33 CFR 157.224 - Dedicated Clean Ballast Tanks Operations Manual.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Dedicated Clean Ballast Tanks... VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Design and Equipment § 157.224 Dedicated Clean Ballast Tanks Operations Manual. Each Dedicated Clean Ballast Tanks Operations Manual...

  11. 33 CFR 157.226 - Dedicated Clean Ballast Tanks Operations Manual: Procedures to be followed.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Dedicated Clean Ballast Tanks... ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Dedicated Clean Ballast Tanks Operations § 157.226 Dedicated Clean Ballast Tanks Operations...

  12. 33 CFR 157.226 - Dedicated Clean Ballast Tanks Operations Manual: Procedures to be followed.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Dedicated Clean Ballast Tanks... ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Dedicated Clean Ballast Tanks Operations § 157.226 Dedicated Clean Ballast Tanks Operations...

  13. 33 CFR 157.212 - Dedicated Clean Ballast Tanks Operations Manual: Not approved.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Dedicated Clean Ballast Tanks... RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.212 Dedicated Clean Ballast Tanks Operations Manual: Not approved. If the Dedicated Clean...

  14. 33 CFR 157.226 - Dedicated Clean Ballast Tanks Operations Manual: Procedures to be followed.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Dedicated Clean Ballast Tanks... ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Dedicated Clean Ballast Tanks Operations § 157.226 Dedicated Clean Ballast Tanks Operations...

  15. 33 CFR 157.224 - Dedicated Clean Ballast Tanks Operations Manual.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Dedicated Clean Ballast Tanks... VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Design and Equipment § 157.224 Dedicated Clean Ballast Tanks Operations Manual. Each Dedicated Clean Ballast Tanks Operations Manual...

  16. 33 CFR 157.212 - Dedicated Clean Ballast Tanks Operations Manual: Not approved.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Dedicated Clean Ballast Tanks... RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.212 Dedicated Clean Ballast Tanks Operations Manual: Not approved. If the Dedicated Clean...

  17. 33 CFR 157.212 - Dedicated Clean Ballast Tanks Operations Manual: Not approved.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Dedicated Clean Ballast Tanks... RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.212 Dedicated Clean Ballast Tanks Operations Manual: Not approved. If the Dedicated Clean...

  18. Promotional mechanism of propane on selective catalytic reduction of NOx by methane over In/H-BEA at low temperature

    NASA Astrophysics Data System (ADS)

    Pan, Hua; Jian, Yanfei; Yu, Yanke; Chen, Ningna; He, Chi; He, Cheng

    2016-12-01

    Effects of propane/methane ratios on NOx reduction by mixtures of methane and propane over In/H-BEA catalyst were investigated at temperatures ranging from 250 to 550 °C. The higher catalytic activity of In/H-BEA was exhibited for CH4-SCR at high temperatures above 450 °C, while the higher NOx conversion was achieved in C3H8-SCR at below 425 °C. A broadened temperature window and enhanced CO2 selectivity were achieved by combining of methane and propane as the co-reductant. The mixtures with propane/methane of 1/2 showed the most superior T50 (325 °C) and T90 (500 °C) temperatures for NOx reduction over In/H-BEA catalyst. For the promotion mechanism of propane on NO reduction by methane at low temperature, the formation of carbonaceous species (e.g. R-COOH) were enhanced by the activation of C3H8 on Brønsted acid sites at low temperature, and further promoted the generation of sbnd NCO species, which was a crucial determining step for NO reduction.

  19. Solubility and thermodynamic behavior of vanillin in propane-1,2-diol+water cosolvent mixtures at different temperatures.

    PubMed

    Shakeel, Faiyaz; Haq, Nazrul; Siddiqui, Nasir A; Alanazi, Fars K; Alsarra, Ibrahim A

    2015-12-01

    The solubilities of bioactive compound vanillin were measured in various propane-1,2-diol+water cosolvent mixtures at T=(298-318)K and p=0.1 MPa. The experimental solubility of crystalline vanillin was determined and correlated with calculated solubility. The results showed good correlation of experimental solubilities of crystalline vanillin with calculated ones. The mole fraction solubility of crystalline vanillin was recorded highest in pure propane-1,2-diol (7.06×10(-2) at 298 K) and lowest in pure water (1.25×10(-3) at 298 K) over the entire temperature range investigated. Thermodynamic behavior of vanillin in various propane-1,2-diol+water cosolvent mixtures was evaluated by Van't Hoff and Krug analysis. The results showed an endothermic, spontaneous and an entropy-driven dissolution of crystalline vanillin in all propane-1,2-diol+water cosolvent mixtures. Based on solubility data of this work, vanillin has been considered as soluble in water and freely soluble in propane-1,2-diol.

  20. Emission measurements for a lean premixed propane/air system at pressures up to 30 atmospheres

    NASA Technical Reports Server (NTRS)

    Roffe, G.; Venkataramani, K. S.

    1978-01-01

    The emissions of a lean premixed system of propane/air were measured in a flametube apparatus. Tests were conducted at inlet temperatures of 600K and 800K and pressures of 10 atm and 30 atm over a range of equivalence ratios. The data obtained were combined with previous data taken in the same apparatus to correlate nitrogen oxide emissions with operating conditions. Sampling probe design was found to have a pronounced effect on measured CO levels but did not influence measurements. The most effective probe tested was one which combined thermal and pressure quenching of the gas sample.

  1. Isolated FeII on Silica As a Selective Propane Dehydrogenation Catalyst

    SciTech Connect

    Hu, Bo; Schweitzer, Neil M.; Zhang, Guanghui; Kraft, Steven J.; Childers, David J.; Lanci, Michael P.; Miller, Jeffrey T.; Hock, Adam S.

    2015-04-17

    ABSTRACT: We report a comparative study of isolated FeII, iron oxide particles, and metallic nanoparticles on silica for non-oxidative propane dehydrogenation. It was found that the most selective catalyst was an isolated FeII species on silica prepared by grafting the open cyclopentadienide iron complex, bis(2,4-dimethyl-1,3-pentadienide) iron(II) or Fe(oCp)2. The grafting and evolution of the surface species was elucidated by 1H NMR, diffuse reflectance infrared Fourier transform spectroscopy and X-ray absorption spectroscopies. The oxidation state and local structure of surface Fe were characterized by X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure. The initial grafting of iron proceeds by one surface hydroxyl Si-OH reacting with Fe(oCp)2 to release one diene ligand (oCpH), generating a SiO2-bound FeII(oCp) species, 1-FeoCp. Subsequent treatment with H2 at 400 °C leads to loss of the remaining diene ligand and formation of nanosized iron oxide clusters, 1-C. Dispersion of these Fe oxide clusters occurs at 650 °C, forming an isolated, ligand-free FeII on silica, 1-FeII, which is catalytically active and highly selective (~99%) for propane dehydrogenation to propene. Under reaction conditions, there is no evidence of metallic Fe by in situ XANES. For comparison, metallic Fe nanoparticles, 2-NP-Fe0, were independently prepared by grafting Fe[N(SiMe3)2]2 onto silica, 2-FeN*, and reducing it at 650 °C in H2. The Fe NPs were highly active for propane conversion but showed poor selectivity (~14%) to propene. Independently prepared Fe oxide clusters on silica display a low activity. The sum of these results suggests that selective propane dehydrogenation occurs at isolated FeII sites.

  2. Novel Sol-Gel Based Pt Nanocluster Catalysts for Propane Dehydrogenation

    SciTech Connect

    Boespflug, Elaine; Kawola, Jeffrey S.; Martino, Anthony; Sault, Allen G.

    1999-08-09

    We report propane dehydrogenation behavior of catalysts prepared using two novel synthesis strategies that combine inverse micelle Pt nanocluster technology with silica and alumina sol-gel processing. Unlike some other sol-gel catalyst preparations. Pt particles in these catalysts are not encapsulated in the support structure and the entire Pt particle surface is accessible for reaction. Turnover frequencies (TOF) for these catalysts are comparable to those obtained over Pt catalysts prepared by traditional techniques such as impregnation, yet the resistance to deactivation by carbon poisoning is much greater in our catalysts. The deactivation behavior is more typical of traditionally prepared PtSn catalysts than of pure Pt catalysts.

  3. Liquid-state theory of hydrocarbon-water systems: Application to methane, ethane, and propane

    SciTech Connect

    Lue, L.; Blankschtein, D.

    1992-10-15

    The authors studied the structural and bulk thermodynamic properties of hydrocarbon (methane, ethane, and propane)-water systems as well as pure water using the site-site Ornstein-Zernike (SSOZ) equation under a variety of different closure relations in order to compare the quantitative predictive capabilities of the various closures. For the hydrocarbon-water systems, the simple point-charge(SPC) potential was used to model water, and the optimized potentials for liquid, simulation (OPLS) were used to model the hydrocarbons. 69 refs., 11 figs., 8 tabs.

  4. N,N'-(Propane-1,3-di-yl)bis-(2-amino-benzamide).

    PubMed

    Sreedasyam, Jagannatha Swamy; Sunkari, Jyothi; Kundha, Shashank; Gundapaneni, Raghava Rao

    2013-05-01

    The title compound, C17H20N4O2, was prepared by the reaction between 1,3-di-amino-propane and isatoic anhydride in water. The carbonyl O atoms are involved in intra-molecular hydrogen bonding with the amine group and inter-molecular hydrogen bonding with an amide H atom of an adjacent mol-ecule. In the crystal, pairs of N-H⋯O hydrogen bonds link mol-ecules into inversion dimers and further N-H⋯O hydrogen bonds link the dimers into ladder-like chains along the a axis.

  5. Vehicular fleet operation on natural gas and propane: An overview. Final research report

    SciTech Connect

    Taylor, D.B.; Mahmassani, H.; Euritt, M.A.

    1992-11-01

    The report attempts to contribute to the timely area of alternative vehicular fuels. It addresses the analysis of fleet operation on alternative fuels, specifically compressed natural gas (CNG) and propane, in terms of both fleet economics and societal impacts. Comprehensive information on engine technology, fueling infrastructure design, and societal impacts are presented. An evaluation framework useful for decisions between any vehicular fuels is developed. The comprehensive fleet cost-effectiveness analysis framework used in previous Project 983 reports is discussed in great detail. This framework/model is flexible enough to allow substantial sensitivity and scenario analysis. The model is used to perform sample analyses of both fleet economic and societal impacts.

  6. Neutron powder diffraction studies as a function of temperature of structure II hydrate formed from propane

    USGS Publications Warehouse

    Rawn, C.J.; Rondinone, A.J.; Chakoumakos, B.C.; Circone, S.; Stern, L.A.; Kirby, S.H.; Ishii, Y.

    2003-01-01

    Neutron powder diffraction data confirm that hydrate samples synthesized with propane crystallize as structure type II hydrate. The structure has been modeled using rigid-body constraints to describe C3H8 molecules located in the eight larger polyhedral cavities of a deuterated host lattice. Data were collected at 12, 40, 100, 130, 160, 190, 220, and 250 K and used to calculate the thermal expansivity from the temperature dependence of the lattice parameters. The data collected allowed for full structural refinement of atomic coordinates and the atomic-displacement parameters.

  7. Engine with pulse-suppressed dedicated exhaust gas recirculation

    SciTech Connect

    Keating, Edward J.; Baker, Rodney E.

    2016-06-07

    An engine assembly includes an intake assembly, a spark-ignited internal combustion engine, and an exhaust assembly. The intake assembly includes a charge air cooler disposed between an exhaust gas recirculation (EGR) mixer and a backpressure valve. The charge air cooler has both an inlet and an outlet, and the back pressure valve is configured to maintain a minimum pressure difference between the inlet of the charge air cooler and an outlet of the backpressure valve. A dedicated exhaust gas recirculation system is provided in fluid communication with at least one cylinder and with the EGR mixer. The dedicated exhaust gas recirculation system is configured to route all of the exhaust gas from the at least one cylinder to the EGR mixer for recirculation back to the engine.

  8. Dedicated bifurcation stents - Mechanistic, hardware, and technical aspects.

    PubMed

    Mishra, Sundeep

    Percutaneous coronary intervention (PCI) in bifurcation lesions is associated with lower success rate, higher acute complication rates and higher event rates in follow-up. The reason for this higher than usual complication rate relates to the relationship between anatomy, flow, and atheroma distribution in bifurcation lesions. Further, stenting these lesions can be a prolonged procedure and can be technically more demanding. The most common complication is the loss of significant side branch (SB). Main vessel (MV) stenting may enhance the carina displacement and atheroma shift across the SB ostium leading to SB ostium narrowing. Finally, complications, if they occur, are more difficult to manage. Dedicated bifurcation stent has been developed to overcome the number of limitations associated with conventional bifurcation PCI. The main advantage of most dedicated bifurcation stents is to allow the operator to perform the procedure on a bifurcation lesion without the need to rewire the SB.

  9. Profiling optimization for big data transfer over dedicated channels

    SciTech Connect

    Yun, D.; Wu, Qishi; Rao, Nageswara S; Kettimuthu, R.; Jung, E. S.

    2016-01-01

    The transfer of big data is increasingly supported by dedicated channels in high-performance networks, where transport protocols play an important role in maximizing applicationlevel throughput and link utilization. The performance of transport protocols largely depend on their control parameter settings, but it is prohibitively time consuming to conduct an exhaustive search in a large parameter space to find the best set of parameter values. We propose FastProf, a stochastic approximation-based transport profiler, to quickly determine the optimal operational zone of a given data transfer protocol/method over dedicated channels. We implement and test the proposed method using both emulations based on real-life performance measurements and experiments over physical connections with short (2 ms) and long (380 ms) delays. Both the emulation and experimental results show that FastProf significantly reduces the profiling overhead while achieving a comparable level of end-to-end throughput performance with the exhaustive search-based approach.

  10. Neurolab - A Space Shuttle Mission Dedicated to Neuroscience Research

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Session JA5 includes short reports concerning: (1) NASA/NIH Neurolab Collaborations; (2) Neurolab Mission: An Example of International Cooperation; (3) Neurolab: An Overview of the Planned Scientific Investigations; (4) EDEN: A Payload for NEUROLAB, dedicated to Neuro Vestibular Research; (5) Neurolab Experiments on the Role of Visual Cues in Microgravity Spatial Orientation; and (6) The Role of Space in the Exploration of the Mammalian Vestibular System.

  11. Don’t Forget About Dedicated Sea Mine Countermeasures

    DTIC Science & Technology

    2005-05-13

    Mine Countermeasures 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Malcolm H. Potts , LCDR, USN 5d. PROJECT NUMBER 5e...DEDICATED SEA MINE COUNTERMEASURES by Malcolm H. Potts LCDR, United States Navy A paper submitted to the Faculty of the Joint Advanced...covertly seeded with a mix of acoustic and contact sea mines, many of which are mal -deployed and became near surface floating explosives. This

  12. Experimental and analytical study of nitric oxide formation during combustion of propane in a jet-stirred combustor

    NASA Technical Reports Server (NTRS)

    Wakelyn, N. T.; Jachimowski, C. J.; Wilson, C. H.

    1978-01-01

    A jet-stirred combustor, constructed of castable zirconia and with an Inconel injector, was used to study nitric oxide formation in propane-air combustion with residence times in the range from 3.2 to 3.3 msec and equivalence ratios varying from 0.7 to 1.4. Measurements were made of combustor operating temperature and of nitric oxide concentration. Maximum nitric oxide concentrations of the order of 55 ppm were found in the range of equivalence ratio from 1.0 to 1.1. A finite-rate chemical kinetic mechanism for propane combustion and nitric oxide formation was assembled by coupling an existing propane oxidation mechanism with the Zeldovich reactions and reactions of molecular nitrogen with hydrocarbon fragments. Analytical studies using this mechanism in a computer simulation of the experimental conditions revealed that the hydrocarbon-fragment-nitrogen reactions play a significant role in nitric oxide formation during fuel-rich combustion.

  13. Catalytic propane reforming mechanism over Mn-Doped CeO2 (111)

    NASA Astrophysics Data System (ADS)

    Krcha, Matthew D.; Janik, Michael J.

    2015-10-01

    MnOx/CeOx mixed oxide systems exhibit encouraging hydrocarbon oxidation activity, without the inclusion of a noble metal. Using density functional theory (DFT) methods, we examined the oxidative reforming path of propane over the Mn-doped CeO2 (1 1 1) surface. A plausible set of elementary reaction steps are identified for conversion of propane to CO/CO2 and H2/H2O over the oxide surface. The rate-limiting reaction process may vary with redox conditions, with C-H dissociation limiting under more oxidizing conditions and more complex reaction sequences, including surface re-oxidation, limiting under highly reducing conditions. The possibility of intermediate desorption from the surface during the reforming process is low, with desorption energies of the intermediates being much less favorable than further surface reactions until CO/CO2 products are formed. The reforming paths over Mn-doped ceria are similar to those previously identified over Zr-doped ceria. The extent of surface reduction and the electronic structure of the surface intermediates are examined.

  14. Surface properties of turbulent premixed propane/air flames at various Lewis numbers

    SciTech Connect

    Lee, T.W.; North, G.L.; Santavicca, D.A. )

    1993-06-01

    Surface properties of turbulent premixed flames including the wrinkled flame perimeter, fraction of the flame pocket perimeter, flame curvature, and orientation distributions have been measured for propane-air flames at Lewis numbers ranging from 0.98 to 1.86 and u[prime]/S[sub L] = 1.42-5.71. The wrinkled flame perimeter is found to be greater for the thermodiffusively unstable Lewis number (Le < 1) by up to 30% in comparison to the most stable condition (Le = 1.86) tested, while the fraction of the flame pocket perimeter shows a similar tendency to be greater for Le < 1. The flame curvature probability density functions are nearly symmetric with respect to the zero mean at all Lewis numbers throughout the range of u[prime]/S[sub L] tested, and show a much stronger dependence on the turbulence condition than on the Lewis number. Similarly, the flame orientation distributions show a trend from anisotropy toward a more uniform distribution with increasing u[prime]/S[sub L] at a similar rate for all Lewis numbers. Thus, for turbulent premixed propane/air flames for a practical range of Lewis number from 0.98 to 1.86, the effect of Lewis number is primarily to affect the flame structures and thereby flame surface areas and flame pocket areas, while the flame curvature and orientation statistics are essentially determined by the turbulence properties.

  15. Influence of propane additives on the detonation characteristics of H2-air mixtures

    NASA Astrophysics Data System (ADS)

    Cheng, Guanbing; Bauer, Pascal; Zitoun, Ratiba

    2014-03-01

    Hydrogen is more and more considered as a potential fuel for propulsion applications. However, due to its low ignition energy and wide flammability limits, H2-air mixtures raise a concern in terms of safety. This aspect can be partly solved by adding an alkane to these mixtures, which plays the role of an inhibitor. The present paper provides data on such binary fuel-air mixtures where various amounts of propane are added to hydrogen. The behavior of the corresponding mixtures, in terms of detonation characteristics and other fundamental properties, such as the cell size of the detonation front and induction delay, are presented and discussed for a series of equivalence ratios and propane addition. The experimental detonation velocity is in good agreement with calculated theoretical Chapman-Jouguet values. Based on soot tracks records, the cell size λ is measured, whereas the induction length L i is derived from data using a GRI-Mech kinetic mechanism. These data allow providing a value of the coefficient K = λ/L i .

  16. Metal–Organic Framework Supported Cobalt Catalysts for the Oxidative Dehydrogenation of Propane at Low Temperature

    PubMed Central

    2016-01-01

    Zr-based metal–organic frameworks (MOFs) have been shown to be excellent catalyst supports in heterogeneous catalysis due to their exceptional stability. Additionally, their crystalline nature affords the opportunity for molecular level characterization of both the support and the catalytically active site, facilitating mechanistic investigations of the catalytic process. We describe herein the installation of Co(II) ions to the Zr6 nodes of the mesoporous MOF, NU-1000, via two distinct routes, namely, solvothermal deposition in a MOF (SIM) and atomic layer deposition in a MOF (AIM), denoted as Co-SIM+NU-1000 and Co-AIM+NU-1000, respectively. The location of the deposited Co species in the two materials is determined via difference envelope density (DED) analysis. Upon activation in a flow of O2 at 230 °C, both materials catalyze the oxidative dehydrogenation (ODH) of propane to propene under mild conditions. Catalytic activity as well as propene selectivity of these two catalysts, however, is different under the same experimental conditions due to differences in the Co species generated in these two materials upon activation as observed by in situ X-ray absorption spectroscopy. A potential reaction mechanism for the propane ODH process catalyzed by Co-SIM+NU-1000 is proposed, yielding a low activation energy barrier which is in accord with the observed catalytic activity at low temperature. PMID:28149950

  17. Absorption Reveals and Hydrogen Addition Explains New Interstellar Aldehydes: Propenal and Propanal

    NASA Technical Reports Server (NTRS)

    Hollis, J. M.; Jewell, P. R.; Lovas, F. J.; Remijan, A.; Mollendal, H.

    2004-01-01

    New interstellar molecules propenal (CH2CHCHO) and propanal (CH3CH2CHO) have been detected largely in absorption toward the star-forming region Sagittarius B2(N) by means of rotational transitions observed with the 100-m Green Bank Telescope (GBT) operating in the range of 18 GHz (lambda approximately 1.7 cm) to 26 GHz (lambda approximately 1.2 cm). The GBT was also used to observe the previously reported interstellar aldehyde propynal (HC2CHO) in Sagittarius B2(N) which is known for large molecules believed to form on interstellar grains. The presence of these three interstellar aldehydes toward Sagittarius B2(N) strongly suggests that simple hydrogen addition on interstellar grains accounts for successively larger molecular species: from propynal to propenal and from propenal to propanal. Energy sources within Sagittarius B2(N) likely permit the hydrogen addition reactions on grain surfaces to proceed. This work demonstrates that successive hydrogen addition is probably an important chemistry route in the formation of a number of complex interstellar molecules. We also searched for but did not detect the three-carbon sugar glyceraldehyde (CH2OHCHOHCHO).

  18. International comparison CCQM-K111—propane in nitrogen

    NASA Astrophysics Data System (ADS)

    van der Veen, Adriaan M. H.; Wouter van der Hout, J.; Ziel, Paul R.; Oudwater, Rutger J.; Fioravante, Andreia L.; Augusto, Cristiane R.; Coutinho Brum, Mariana; Uehara, Shinji; Akima, Dai; Bae, Hyun Kil; Kang, Namgoo; Woo, Jin-Chun; Liaskos, Christina E.; Rhoderick, George C.; Jozela, Mudalo; Tshilongo, James; Ntsasa, Napo G.; Botha, Angelique; Brewer, Paul J.; Brown, Andrew S.; Bartlett, Sam; Downey, Michael L.; Konopelko, L. A.; Kolobova, A. V.; Pankov, A. A.; Orshanskaya, A. A.; Efremova, O. V.

    2017-01-01

    This key comparison aims to assess the core capabilities of the participants in gas analysis. Such competences include, among others, the capabilities to prepare primary standard gas Mixtures (PSMs), perform the necessary purity analysis on the materials used in the gas mixture preparation, the verification of the composition of newly prepared PSMs against existing ones, and the capability of calibrating the composition of a gas mixture. According to the Strategy for Key Comparisons of the Gas Analysis Working Group, this key comparison is classified as a track A key comparison, which means that the results of this key comparison can be used to underpin calibration and measurement capabilities using the flexible scheme, and for propane under the default scheme. The artefacts were binary mixtures of propane in nitrogen at a nominal amount-of-substance fraction level of 1000 μmol/mol. The values and uncertainties from the gravimetric gas mixture preparation were used as key comparison reference values (KCRVs). Each transfer standard had its own KCRV. The results are generally good. All results but one are within +/- 0.2 % of the KCRV. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  19. Comparison of Propane and Methane Performance and Emissions in a Turbocharged Direct Injection Dual Fuel Engine

    SciTech Connect

    Gibson, C. M.; Polk, A. C.; Shoemaker, N. T.; Srinivasan, K. K.; Krishnan, S. R.

    2011-01-01

    With increasingly restrictive NO x and particulate matter emissions standards, the recent discovery of new natural gas reserves, and the possibility of producing propane efficiently from biomass sources, dual fueling strategies have become more attractive. This paper presents experimental results from dual fuel operation of a four-cylinder turbocharged direct injection (DI) diesel engine with propane or methane (a natural gas surrogate) as the primary fuel and diesel as the ignition source. Experiments were performed with the stock engine control unit at a constant speed of 1800 rpm, and a wide range of brake mean effective pressures (BMEPs) (2.7-11.6 bars) and percent energy substitutions (PESs) of C 3 H 8 and CH 4. Brake thermal efficiencies (BTEs) and emissions (NO x, smoke, total hydrocarbons (THCs), CO, and CO 2) were measured. Maximum PES levels of about 80-95% with CH 4 and 40-92% with C 3 H 8 were achieved. Maximum PES was limited by poor combustion efficiencies and engine misfire at low loads for both C 3 H 8 and CH 4, and the onset of knock above 9 bar BMEP for C 3 H 8. While dual fuel BTEs were lower than straight diesel BTEs at low loads, they approached diesel BTE values at high loads. For dual fuel operation, NO x and smoke reductions (from diesel values) were as high as 66-68% and 97%, respectively, but CO and THC emissions were significantly higher with increasing PES at all engine loads

  20. Spectral and nonlinear optical studies of Propane-1, 3-diaminium nitrate

    NASA Astrophysics Data System (ADS)

    Ayadi, R.; Lhoste, J.; Ngo, H. M.; Ledoux-Rak, I.; Mhiri, T.; Boujelbene, M.

    2016-08-01

    Propane-1, 3-diaminium nitrate [C3H12N2] (NO3)2 (PDAN), an hybrid organic-inorganic nonlinear optical material combining an acentric octupolar moiety (nitrate) with a centrosymmetric organic molecule (Propane-1, 3-diaminium) was prepared by slow evaporation technique at room temperature from its aqueous solution. Good quality and well-developed crystals of size 0.133 mm×0.092 mm×0.078 mm were harvested from the mother solution. The grown single crystals were characterized for their spectral, thermal, linear and second order nonlinear optical properties. Solid-state 13C and 1H MAS-NMR spectroscopies are in agreement with the X-ray structure. The decomposition of the title compound is confirmed by the thermogravimetric analysis (TGA). The UV-visible absorption spectrum, show that PDAN is suitable for frequency doubling applications in a wide spectral range in the visible and near IR. The NLO response of the crystal was evaluated using a SHG powder technique, indicating an effective quadratic nonlinear coefficient two times higher than that of KDP in spite of the low hyperpolarizability of the nitrate ion and of the centrosymmetric character of the diaminium derivative.

  1. Studying solutions at high shear rates: a dedicated microfluidics setup.

    PubMed

    Wieland, D C F; Garamus, V M; Zander, T; Krywka, C; Wang, M; Dedinaite, A; Claesson, P M; Willumeit-Römer, R

    2016-03-01

    The development of a dedicated small-angle X-ray scattering setup for the investigation of complex fluids at different controlled shear conditions is reported. The setup utilizes a microfluidics chip with a narrowing channel. As a consequence, a shear gradient is generated within the channel and the effect of shear rate on structure and interactions is mapped spatially. In a first experiment small-angle X-ray scattering is utilized to investigate highly concentrated protein solutions up to a shear rate of 300000 s(-1). These data demonstrate that equilibrium clusters of lysozyme are destabilized at high shear rates.

  2. UV-PEDD photometry dedicated for bioanalytical uses.

    PubMed

    Tymecki, Łukasz; Brodacka, Luiza; Rozum, Beata; Koncki, Robert

    2009-07-01

    Detection of p-nitrophenol, a product of several enzymatic reactions, is useful and important in many fields of modern bioanalytics. Here, we have developed and applied a complete photometer dedicated for such measurements that is extremely economic and easily customized for specific experimental setups. The instrument consists only of paired emitter-detector diodes (PEDDs) coupled with an extremely simple and low-cost signal transduction system. The experimental data confirmed that this photometric system adapted for cuvette as well as flow measurements can be applied for fast and reproducible determination of alkaline phosphatase (ALP) activity.

  3. A Dedicated Genetic Algorithm for Localization of Moving Magnetic Objects

    PubMed Central

    Alimi, Roger; Weiss, Eyal; Ram-Cohen, Tsuriel; Geron, Nir; Yogev, Idan

    2015-01-01

    A dedicated Genetic Algorithm (GA) has been developed to localize the trajectory of ferromagnetic moving objects within a bounded perimeter. Localization of moving ferromagnetic objects is an important tool because it can be employed in situations when the object is obscured. This work is innovative for two main reasons: first, the GA has been tuned to provide an accurate and fast solution to the inverse magnetic field equations problem. Second, the algorithm has been successfully tested using real-life experimental data. Very accurate trajectory localization estimations were obtained over a wide range of scenarios. PMID:26393598

  4. Enabling Dedicated, Affordable Space Access Through Aggressive Technology Maturation

    NASA Technical Reports Server (NTRS)

    Jones, Jonathan E.; Kibbey, Timothy P.; Cobb, C. Brent; Harris, Lawanna L.

    2014-01-01

    A launch vehicle at the scale and price point which allows developers to take reasonable risks with high payoff propulsion and avionics hardware solutions does not exist today. Establishing this service provides a ride through the proverbial technology "valley of death" that lies between demonstration in laboratory and flight environments. NASA's NanoLaunch effort will provide the framework to mature both earth-to-orbit and on-orbit propulsion and avionics technologies while also providing affordable, dedicated access to low earth orbit for cubesat class payloads.

  5. BTeV - A dedicated B experiment at the Tevatron

    SciTech Connect

    David C. Christian

    2002-12-17

    BTeV is a dedicated b-physics experiment that is expected to begin operation at the Fermilab Tevatron in 2008. BTeV is designed to take full advantage of the large production cross section of b particles (including B{sub S}) in high energy hadron collisions. A quick description of the BTeV spectrometer is given in this paper. Two unique aspects of BTeV, the pixel-based trigger and the high quality lead tungstate electromagnetic calorimeter, are described in slightly greater detail.

  6. Pile a combustible a electrolyte polymere solide a consommation directe de gaz propane

    NASA Astrophysics Data System (ADS)

    Rodriguez Varela, Francisco Javier

    A Polymer Electrolyte Membrane Fuel Cell working with propane as the fuel has been studied. The propane was directly introduced into the cell without previous external reforming, resulting in a Direct Propane Fuel Cell (DPFC). Electrodes of composition 40% Pt/C and 40% PtRu/C (commercial), 20% PtOx/C and 20% Pt/C + 10% CrO3 (home-prepared) have been tested as anodes catalysts in the DPFC. Commercial NafionRTM 117 membranes were used as polymer electrolytes. The anode electrocatalysts were also tested in a H2/O2 fuel cell in order to asses their electrocatalytical characteristics. It has been shown by the polarization curves that the anodes based on 40% Pt/C and 40% PtRu/C provide higher current densities from the H2 /O2 fuel cell than the anodes 20% PtOx/C and 20% Pt/C + 10% CrO3. However, a more in-depth analysis has revealed important features of both home-prepared anodes. For example, relatively high current densities were obtained from these electrocatalysts during the oxidation of H2. Also, the lower open circuit anode potential for the oxidation of H2 has been obtained with the anode 20% PtOx/C. On the other hand, the current density at high cell potentials (970 mV) of the fuel cell based on the anode 20% Pt/C + 10% CrO3 was higher than the current densities of 40% Pt/C and 40% PtRu/C. Kinetic data has shown that the catalyst 20% Pt/C + 10% CrO3 provided a more important exchange current density than the rest of the anode catalysts. It has also been shown that 20% Pt/C + 10% CrO3 possess the largest mass activity while the lower mass activity is that of the catalyst 40% Pt/C. These results have revealed that the home-prepared anodes based on 20% PtOx/C and 20% Pt/C + 10% CrO 3 have important electrocatalytic characteristics for PEM fuel cells applications. Samples of the electrocatalysts were analysed by X-ray diffraction and transmission electron microscopy. A polycrystalline structure has been shown for all Pt-based materials except for 20% PtOx/C which

  7. Developing a Dedicated GISAXS Beamline at the APS

    NASA Astrophysics Data System (ADS)

    Li, Xuefa; Narayanan, Suresh; Sprung, Michael; Sandy, Alec; Lee, Dong Ryeol; Wang, Jin

    2007-01-01

    As an increasingly important structural-characterization technique, grazing-incidence small-angle scattering (GISAXS) finds vast applications in nanostructures and nanocomposites at surfaces and interfaces for in situ and real-time studies because of its probing q-range (10-3 - 1 nm-1) and temporal resolution (10-3 - 1 s). At the Advanced Photon Source (APS), GISAXS techniques under thin-film waveguide-based resonance conditions were developed to study the diffusion phenomena in nanoparticle/polymer nanocomposites. Also, the kinematics of nanoparticle crystal formation at air/liquid interfaces has been obtained by the similar method in real time during the liquid droplet evaporation. To meet the strong demand from the nanoscience community, a dedicated GISAXS beamline has been designed and constructed as a part of the 8-ID-E beamline at the APS. This dedicated GISAXS setup was developed based on a 4-circle diffractometer so that precise reflectivity of the sample can be measured to complement the GISAXS analysis under the dynamical refection conditions.

  8. Efficient iterative image reconstruction algorithm for dedicated breast CT

    NASA Astrophysics Data System (ADS)

    Antropova, Natalia; Sanchez, Adrian; Reiser, Ingrid S.; Sidky, Emil Y.; Boone, John; Pan, Xiaochuan

    2016-03-01

    Dedicated breast computed tomography (bCT) is currently being studied as a potential screening method for breast cancer. The X-ray exposure is set low to achieve an average glandular dose comparable to that of mammography, yielding projection data that contains high levels of noise. Iterative image reconstruction (IIR) algorithms may be well-suited for the system since they potentially reduce the effects of noise in the reconstructed images. However, IIR outcomes can be difficult to control since the algorithm parameters do not directly correspond to the image properties. Also, IIR algorithms are computationally demanding and have optimal parameter settings that depend on the size and shape of the breast and positioning of the patient. In this work, we design an efficient IIR algorithm with meaningful parameter specifications and that can be used on a large, diverse sample of bCT cases. The flexibility and efficiency of this method comes from having the final image produced by a linear combination of two separately reconstructed images - one containing gray level information and the other with enhanced high frequency components. Both of the images result from few iterations of separate IIR algorithms. The proposed algorithm depends on two parameters both of which have a well-defined impact on image quality. The algorithm is applied to numerous bCT cases from a dedicated bCT prototype system developed at University of California, Davis.

  9. SCOSII OL: A dedicated language for mission operations

    NASA Technical Reports Server (NTRS)

    Baldi, Andrea; Elgaard, Dennis; Lynenskjold, Steen; Pecchioli, Mauro

    1994-01-01

    The Spacecraft Control and Operations System 2 (SCOSII) is the new generation of Mission Control Systems (MCS) to be used at ESOC. The system is generic because it offers a collection of standard functions configured through a database upon which a dedicated MCS is established for a given mission. An integral component of SCOSII is the support of a dedicated Operations Language (OL). The spacecraft operation engineers edit, test, validate, and install OL scripts as part of the configuration of the system with, e.g., expressions for computing derived parameters and procedures for performing flight operations, all without involvement of software support engineers. A layered approach has been adopted for the implementation centered around the explicit representation of a data model. The data model is object-oriented defining the structure of the objects in terms of attributes (data) and services (functions) which can be accessed by the OL. SCOSII supports the creation of a mission model. System elements as, e.g., a gyro are explicit, as are the attributes which described them and the services they provide. The data model driven approach makes it possible to take immediate advantage of this higher-level of abstraction, without requiring expansion of the language. This article describes the background and context leading to the OL, concepts, language facilities, implementation, status and conclusions found so far.

  10. Anaerobic degradation of propane and butane by sulfate-reducing bacteria enriched from marine hydrocarbon cold seeps

    PubMed Central

    Jaekel, Ulrike; Musat, Niculina; Adam, Birgit; Kuypers, Marcel; Grundmann, Olav; Musat, Florin

    2013-01-01

    The short-chain, non-methane hydrocarbons propane and butane can contribute significantly to the carbon and sulfur cycles in marine environments affected by oil or natural gas seepage. In the present study, we enriched and identified novel propane and butane-degrading sulfate reducers from marine oil and gas cold seeps in the Gulf of Mexico and Hydrate Ridge. The enrichment cultures obtained were able to degrade simultaneously propane and butane, but not other gaseous alkanes. They were cold-adapted, showing highest sulfate-reduction rates between 16 and 20 °C. Analysis of 16S rRNA gene libraries, followed by whole-cell hybridizations with sequence-specific oligonucleotide probes showed that each enrichment culture was dominated by a unique phylotype affiliated with the Desulfosarcina-Desulfococcus cluster within the Deltaproteobacteria. These phylotypes formed a distinct phylogenetic cluster of propane and butane degraders, including sequences from environments associated with hydrocarbon seeps. Incubations with 13C-labeled substrates, hybridizations with sequence-specific probes and nanoSIMS analyses showed that cells of the dominant phylotypes were the first to become enriched in 13C, demonstrating that they were directly involved in hydrocarbon degradation. Furthermore, using the nanoSIMS data, carbon assimilation rates were calculated for the dominant cells in each enrichment culture. PMID:23254512

  11. Recovery Act: Demonstration of a SOFC Generator Fueled by Propane to Provide Electrical Power to Real World Applications

    SciTech Connect

    Bessette, Norman

    2016-08-01

    The objective of this project provided with funds through the American Recovery and Reinvestment Act of 2009 (ARRA) was to demonstrate a Solid Oxide Fuel Cell (SOFC) generator capable of operation on propane fuel to improve efficiency and reduce emissions over commercially available portable generators. The key objectives can be summarized as: Development of two portable electrical generators in the 1-3kW range utilizing Solid Oxide Fuel Cells and propane fuel; The development and demonstration of a proof-of-concept electro-mechanical propane fuel interface that provides a user friendly capability for managing propane fuel; The deployment and use of the fuel cell portable generators to power media production equipment over the course of several months at multiple NASCAR automobile racing events; The deployment and use of the fuel cell portable generators at scheduled events by first responders (police, fire) of the City of Folsom California; and Capturing data with regard to the systems’ ability to meet Department of Energy (DOE) Technical Targets and evaluating the ease of use and potential barriers to further adoption of the systems.

  12. Micellar and bicontinuous microemulsions formed in both near-critical and supercritical propane with didodecyldimethylammonium bromide and water

    SciTech Connect

    Tingey, J.M.; Fulton, J.L.; Matson, D.W.; Smith, R.D. )

    1991-02-07

    Bicontinuous microemulsions readily form in liquid propane at 25C and pressures from 10 to 500 bar with the addition of the surfactant didodecyldimethylammonium bromide (DDAB) and water. The phase behavior of this system is much like that of the normal liquid alkanes, C{sub 6}-C{sub 10}, but with unusual and dramatic effects due to pressure. When the pressure of the solution is increased from 80 to 400 bar with the addition of pure propane, the conductivity is observed to decrease by 3 orders of magnitude. In accord with existing structural models of conventional liquid microemulsion systems, these changes in the conductivity are ascribed to changes in the interface region as the propane solvent penetrates and solvates the hydrocarbon tails of the surfactant. The corresponding supercritical propane system studied at 100C is best explained as a micellar microemulsion with an oil-continuous phase in which the structure is also affected by the amount of water or the pressure of the system.

  13. Catalytic coatings on steel for low-temperature propane prereforming to solid oxide fuel cell (SOFC) application.

    PubMed

    Alphonse, Pierre; Ansart, Florence

    2009-08-15

    Catalyst layers (4-20 microm) of rhodium (1 wt%) supported on alumina, titania, and ceria-zirconia (Ce(0.5)Zr(0.5)O(2)) were coated on stainless-steel corrugated sheets by dip-coating in very stable colloidal dispersions of nanoparticles in water. Catalytic performances were studied for low-temperature (< or = 500 degrees C) steam reforming of propane at a steam to carbon ratio equal to 3 and low contact time (approximately 0.01 s). The best catalytic activity for propane steam reforming was observed for titania and ceria-zirconia supports for which propane conversion started at 250 degrees C and was more than three times better at 350 degrees C than conversion measured on alumina catalyst. For all catalysts a first-order kinetics was found with respect to propane at 500 degrees C. Addition of PEG 2000 in titania and ceria-zirconia sols eliminated the film cracking observed without additive with these supports. Besides, the PEG addition strongly expanded the porosity of the layers, so that full catalytic efficiency was maintained when the thickness of the ceria-zirconia and titania films was increased.

  14. Refolding additive, dimethylbenzylammonium propane sulfonate (NDSB- 256), accelerates gly-pro cis-trans isomerization.

    PubMed

    Wang, Haimei; Hosoda, Kazuo; Terawaki, Shin-Ichi; Wakamatsu, Kaori

    2014-01-01

    Proline cis-trans isomerization plays a key role in the rate-determining steps of protein folding, and many different peptide-proline cis-trans isomerases (PPIases) catalyze this reaction. The acceleration of isomerization would be beneficial for in vitro refolding of protein preparations for industrial and research purposes. So we analyzed whether low-molecular-weight compounds that have been reported to enhance protein refolding have the activity to accelerate the isomerization. To evaluate the effects of chemicals on the isomerization rate, we set up a new NMR (EXSY) method that is invulnerable to their inhibitory activity, if any, and to their large NMR signals. With this method, we found that dimethylbenzylammonium propane sulfonate (NDSB-256) increase the isomerization rate in a concentration-dependent manner for the first time. Acceleration by imidazole (suggested but not experimentally confirmed) was also demonstrated. Arginine, a most popular refolding additive, did not show any significant effects on the isomerization reaction as expected.

  15. Epitaxial growth of SiC from Al?Si solution reacting with propane gas

    NASA Astrophysics Data System (ADS)

    Tanaka, A.; Ataka, T.; Ohkura, E.; Katsuno, H.

    2004-09-01

    A new low-temperature LPE technique has been developed. SiC layers were grown on a Si-face of 6H-SiC substrates from Al-Si solution reacting with propane gas at 1000°C. Morphology of the as-grown surface of the layers changed depending on whether the solution was saturated with Si or not. Based on the observation, two growth modes, corresponding to segregation dominance or surface diffusion dominance, were discussed. The use of off-axis substrates made the growth rate increase remarkably. The thickness reached about 10-μm after 8-h growth. PL measurements revealed that the polytype of the grown layers belongs to a hexagonal group.

  16. Preparation of nanoporous graphene and the application of its nanocomposite membrane in propylene/propane separation

    NASA Astrophysics Data System (ADS)

    Sun, Hai-Xiang; Yuan, Bing-Bing; Li, Peng; Wang, Tao; Xu, Yan-Yan

    2015-11-01

    Chemically reduced graphene oxide containing hydroxyl groups and a wide size distribution of nanopores was prepared by a facile one-pot hydrothermal method. The resulting material was characterized by transmission electron microscopy (TEM), Raman spectroscopy, surface area measurement and attenuated total reflection infrared spectroscopy (ATR-FTIR), respectively. It was found that this reduced graphene oxide exhibited more clear nanopores and hydroxyl groups in the basal plane. Then the morphologies of the nanocomposite membrane incorporated into the nanoporous graphene were investigated through scanning electron microscopy (SEM), and the permeation test also was performed. Notably, the results showed that the nanocomposite membrane had a homogenous morphology and a better performance (separation factor 11.09) than polymer membrane in the separation of propylene/propane. This work demonstrates that nanoporous graphene exhibits great potential in the field of olefin/paraffin separation.

  17. Production of hydrogen by autothermal reforming of propane over Ni/delta-Al2O3.

    PubMed

    Lee, Hae Ri; Lee, Kwi Yeon; Park, Nam Cook; Shin, Jae Soon; Moon, Dong Ju; Lee, Byung Gwon; Kim, Young Chul

    2006-11-01

    The performance of Ni/delta-Al2O3 catalyst in propane autothermal reforming (ATR) for hydrogen production was investigated in the present study. The catalysts were characterized using XRD, TEM, and SEM. The activity of the Ni/delta-Al2O3 catalyst manufactured by the water-alcohol method was better than those of the catalysts manufactured by the impregnation and chemical reduction methods. The Ni/delta-Al2O3 catalysts were modified by the addition of promoters such as Mg, La, Ce, and Co, in order to improve their stability and yield. Hydrogen production was the largest for the Ni-Co-CeO2/Al2O3, catalyst.

  18. Experimental investigation on plasma-assisted combustion characteristics of premixed propane/air mixture

    NASA Astrophysics Data System (ADS)

    Liu, Xingjian; He, Liming; Yu, Jinlu; Zeng, Hao; Jin, Tao

    2015-06-01

    A detailed study on the plasma-assisted combustion (PAC) characteristics of premixed propane/air mixture is presented. The PAC is measured electrically, as well as optically with a multichannel spectrometer. The characteristics are demonstrated by stable combustion temperature and combustion stability limits, and the results are compared with conventional combustion (CC). Stable combustion temperature measurements show that the introduction of PAC into combustion system can increase the stable combustion temperature, and the increment is more notable with an increase of discharge voltage. Besides, the rich and weak limits of combustion stability are both enlarged when plasma is applied into the combustion process and the increase of discharge voltage results in the expansion of combustion stability limits as well. The measurements of temperature head and emission spectrum illustrate that the kinetic enhancement caused by reactive species in plasma is the main enhancement pathway for current combustion system.

  19. New Whole-House Solutions Case Study: Hydronic Heating Coil Versus Propane Furnace, Rehoboth Beach, Delaware

    SciTech Connect

    2014-01-01

    In this project involving two homes, the IBACOS team evaluated the performance of the two space conditioning systems and the modeled efficiency of the two tankless domestic hot water systems relative to actual occupant use. Each house was built by Insight Homes and is 1,715-ft2 with a single story, three bedrooms, two bathrooms, and the heating, ventilation, and air conditioning systems and ductwork located in conditioned crawlspaces. The standard house, which the builder offers as its standard production house, uses an air source heat pump (ASHP) with supplemental propane furnace heating. The Building America test house uses the same ASHP unit with supplemental heat provided by the DHW heater (a combined DHW and hydronic heating system, where the hydronic heating element is in the air handler).

  20. Argon/propane ionization-chamber dosimetry for mixed x-ray/neutron fields.

    PubMed

    Schulz, R J

    1978-01-01

    The photoneutrons produced by high-energy x-ray machines can diffuse through the mazes usually employed at the treatment-room entrance and readily penetrate the lead-lined doors used for x-ray shielding. The measurement of these neutrons in the presence of x-rays and the determination of dose equivalent poses a problem for which there is currently no standard method of solution. In order to separate x-ray dose from neutron dose, the author employed an ionization chamber alternately filled with argon or propane. The response characteristics of this chamber to x-ray and neutrons are described. Quality factors were determined from a calculated neutron spectrum. As a result of these measurements, a 10-in. polyethylene door was added to the entranceway of a 25-MV linear accelerator.

  1. Lean Combustion Limits of a Confined Premixed-Prevaporized Propane Jet

    NASA Technical Reports Server (NTRS)

    Huck, K. L.; Marek, C. J.

    1978-01-01

    Lean blowout limits were reported for a premixed prevaporized propane jet issuing into a cylindrical combustor. A single hole in a flat plate was used as a flameholder. Flameholders with various hole diameters were used. Jet velocities were varied from 3 to 290 meters per second. The combustor cross sectional area was changed by using different quartz liners of 12.7 and 22.2 millimeters diameters. As a result the combustor Reynolds number varied from 1000 to 9000. Stability was achieved at laminar as well as turbulent conditions. Three zones of flame stability were observed. The blowout equivalence ratio varied with step size and the combustor and jet Reynolds numbers. The combustor inlet mixture temperature was 395 K, and the combustor pressure was 1 atmosphere.

  2. Lean-limit extinction of propane/air mixtures in the stagnation-point flow

    NASA Technical Reports Server (NTRS)

    Law, C. K.; Ishizuka, S.; Mizomoto, M.

    1981-01-01

    The extinction limits of lean propane/air mixtures in the stagnation-point flow of a flat surface were mapped as functions of the surface temperature and the mixture concentration, velocity, and temperature. The maximum flame temperatures and the flame locations were also measured. The results show that the extinction limits are extremely insensitive to the nature of the surface, which can be heated to 1000 C. On the other hand preheating the gas mixture increases the flame temperature by an almost equal amount and therefore significantly extends the extinction limits. It is also found that at extinction the maximum flame temperatures and the flame locations, which when scaled with the velocity gradient, assume almost constant values independent of the other system variables investigated.

  3. Carbon nanofibers modified with heteroatoms as metal-free catalysts for the oxidative dehydrogenation of propane.

    PubMed

    Marco, Yanila; Roldán, Laura; Muñoz, Edgar; García-Bordejé, Enrique

    2014-09-01

    Carbon nanofibres (CNFs) were modified with B and P by an ex situ approach. In addition, CNFs doped with N were prepared in situ using ethylenediamine as the N and C source. After calcination, the doped CNFs were used as catalysts for the oxidative dehydrogenation of propane. For B-CNFs, the effects of boron loading and calcination temperature on B speciation and catalytic conversion were studied. For the same reaction temperatures and conversions, B- and P-doped CNFs exhibited higher selectivities to propene than pristine CNFs. The N-CNFs were the most active but the least selective of the catalysts tested here. Our results also show that the type of P precursor affects the selectivity to propene and that CNFs modified using triphenylphosphine as the precursor provided the highest selectivity at isoconversion.

  4. Prediction of equilibrium distributions of isotopologues for methane, ethane and propane using density functional theory

    NASA Astrophysics Data System (ADS)

    Piasecki, Alison; Sessions, Alex; Peterson, Brian; Eiler, John

    2016-10-01

    Many previous studies have examined abundances of deuterium (D) and 13C within small organic molecules. Recent advances in analytical instrumentation add the abilities to measure site-specific and multiply substituted isotopologues of natural organics. Here we perform first-principles calculations of the equilibrium distributions of 13C and D in the volatile alkanes (including both single and multiple substitutions), as a guide to the interpretation of current measurements and as a basis for anticipating isotope effects that might be examined with future analytical techniques. The models we present illustrate several common themes of the isotopic structures of the small alkanes, including; temperature dependent enrichment of clumped isotope species, with amplitudes in the order D-D > 13C-D > 13C-13C; similarity in strength of such clumped isotope effects between different molecules (e.g., 13C-D clumping is ∼5‰ enriched at 300 K in methane, ethane and propane); a ∼10× contrast between the amplitudes of stronger adjacent substitution of two heavy isotopes vs. weaker non-adjacent substitution; temperature-dependent site-specific fractionation of D and 13C into interior positions of molecules relative to terminal methyl groups; and a relatively simple additive effect to the overall amplitude of enrichment when clumped and site specific effects combine in the same isotopologue. We suggest that the most promising tools suggested by our results are isotopic thermometers based on site-specific distribution of deuterium, which exhibits strong (∼100‰), highly temperature dependent fractionation between methyl groups and methylene carbon positions in propane (and likely other larger n-alkanes).

  5. [Smog chamber simulation of ozone formation from atmospheric photooxidation of propane].

    PubMed

    Huang, Li-hua; Mo, Chuang-rong; Xu, Yong-fu; Jia, Long

    2012-08-01

    Atmospheric photochemical reactions of propane and NO, were simulated with a self-made smog chamber. The effects of relative humidity (RH) and [C3H8]0/[NOx]0 ratio on ozone formation were studied. The results showed that both the maximum ozone concentration and the maximum value of incremental reactivity (IRmax) of propane decreased linearly with increasing RH. Under lower RH conditions, the occurrence time of peak ozone concentration was about 22 h after the beginning of reaction, and IRmax varied from 0.0231 to 0.0391, while under higher RH conditions the occurrence time of peak ozone concentration was 16 h, and IRmax ranged from 0.0172 to 0.0320. During the 20 h of reaction, within the first 12 h RH did not significantly affect the yield of acetone, whereas after 12 h the lower RH condition could lead to relatively greater amount of acetone. During the first 4-20 h of experiments, acetone concentrations ranged from 153 x 10(-9) to 364 x 10(-9) at 17% RH and from 167 x 10(-9) to 302 x 10(-9) at 62% RH, respectively. Maximum ozone concentrations decreased with increasing [C3H8]0/[NOx]0 ratio and a better negative linear relationship between them was obtained under the lower RH conditions. The smog chamber data and the results from simulation of the C3H8-NOx reactions using the sub-mechanism of MCM were compared, and a significant deviation was found between these two results.

  6. Synthesis and Characterization of Gold Clusters Ligated with 1,3-Bis(dicyclohexylphosphino)propane

    SciTech Connect

    Johnson, Grant E.; Priest, Thomas A.; Laskin, Julia

    2013-09-01

    In this multidisciplinary study we combine chemical reduction synthesis of novel gold clusters in solution with high-resolution analytical mass spectrometry (MS) to gain insight into the composition of the gold clusters and how their size, ionic charge state and ligand substitution influences their gas-phase fragmentation pathways. Ultra small cationic gold clusters ligated with 1,3-bis(dicyclohexylphosphino)propane (DCPP) were synthesized for the first time and introduced into the gas phase using electrospray ionization (ESI). Mass-selected cluster ions were fragmented employing collision induced dissociation (CID) and the product ions were analysed using MS. The solutions were found to contain the multiply charged cationic gold clusters Au9L43+, Au13L53+, Au6L32+, Au8L32+ and Au10L42+ (L = DCPP). The gas-phase fragmentation pathways of these cluster ions were examined systematically employing CID combined with MS. In addition, CID experiments were performed on related gold clusters of the same size and ionic charge state but capped with 1,3-bis(diphenylphosphino)propane (DPPP) ligands containing phenyl functional groups at the two phosphine centers instead of cyclohexane rings. It is shown that this relatively small change in the molecular substitution of the two phosphine centers in diphosphine ligands (C6H11 versus C6H5) exerts a pronounced influence on the size of the species that are preferentially formed in solution during reduction synthesis as well as the gas-phase fragmentation channels of otherwise identical gold cluster ions. The mass spectrometry results indicate that in addition to the length of the alkyl chain between the two phosphine centers, the substituents at the phosphine centers also play a crucial role in determining the composition, size and stability of diphosphine ligated gold clusters synthesized in solution.

  7. 33 CFR 157.208 - Dedicated Clean Ballast Tanks Operations Manual for foreign tank vessels: Submission.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Dedicated Clean Ballast Tanks... MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.208 Dedicated Clean Ballast Tanks Operations Manual for foreign tank...

  8. 33 CFR 157.210 - Approved Dedicated Clean Ballast Tanks Operations Manual.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.210 Approved Dedicated Clean Ballast Tanks Operations Manual. If the manuals submitted under § 157.206... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Approved Dedicated Clean...

  9. 33 CFR 157.210 - Approved Dedicated Clean Ballast Tanks Operations Manual.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Approved Dedicated Clean Ballast... RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.210 Approved Dedicated Clean Ballast Tanks Operations Manual. If the manuals submitted under §...

  10. 33 CFR 157.210 - Approved Dedicated Clean Ballast Tanks Operations Manual.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Approved Dedicated Clean Ballast... RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.210 Approved Dedicated Clean Ballast Tanks Operations Manual. If the manuals submitted under §...

  11. 33 CFR 157.208 - Dedicated Clean Ballast Tanks Operations Manual for foreign tank vessels: Submission.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Dedicated Clean Ballast Tanks... MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.208 Dedicated Clean Ballast Tanks Operations Manual for foreign tank...

  12. 33 CFR 157.208 - Dedicated Clean Ballast Tanks Operations Manual for foreign tank vessels: Submission.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Dedicated Clean Ballast Tanks... MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.208 Dedicated Clean Ballast Tanks Operations Manual for foreign tank...

  13. 33 CFR 157.210 - Approved Dedicated Clean Ballast Tanks Operations Manual.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Approved Dedicated Clean Ballast... RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.210 Approved Dedicated Clean Ballast Tanks Operations Manual. If the manuals submitted under §...

  14. 33 CFR 157.208 - Dedicated Clean Ballast Tanks Operations Manual for foreign tank vessels: Submission.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Dedicated Clean Ballast Tanks... MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.208 Dedicated Clean Ballast Tanks Operations Manual for foreign tank...

  15. 33 CFR 157.208 - Dedicated Clean Ballast Tanks Operations Manual for foreign tank vessels: Submission.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Dedicated Clean Ballast Tanks... MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.208 Dedicated Clean Ballast Tanks Operations Manual for foreign tank...

  16. 33 CFR 157.210 - Approved Dedicated Clean Ballast Tanks Operations Manual.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Approved Dedicated Clean Ballast... RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.210 Approved Dedicated Clean Ballast Tanks Operations Manual. If the manuals submitted under §...

  17. Comparison of Microcosm Tests and a Field Demonstration of Cometabolic Air Sparging With Propane for the Bioremediation of Trichloroethylene and cis-Dichloroethylene

    NASA Astrophysics Data System (ADS)

    Timmins, B.; Dolan, M. E.; Tovannabootr, A.; Azizian, M.; Semprini, L.; Magar, V. S.; Leeson, A.

    2001-12-01

    Cometabolic air sparging (CAS) is an innovative form of conventional air sparging, and is designed to degrade or remove chlorinated aliphatic hydrocarbon compounds (CAHs) in groundwater and to potentially treat these contaminants in the vadose zone. A CAS demonstration was conducted at McClellan AFB, California, for removal of chloroethenes (TCE, cis-DCE) from groundwater using propane as the cometabolic substrate. In support of this field demonstration both groundwater and vadose zone microcosm studies were performed. The microcosms were created with groundwater and aquifer materials from the demonstration site. Concentrations of compounds in the microcosms were created to mimic conditions where the demonstration was performed. The microcosms were used to test the potential of the propane-utilizers to transform the CAHs of interest, and determine their nutrient requirements while transforming these compounds. Results from the first season of field-testing showed propane-utilizers could be effectively stimulated in the saturated zone with repeated intermediate sparging of propane and air. The lag time for effective propane utilization to be observed in the field was about 30 to 40 days, while in laboratory microcosms the lag period was about 12 days. Consistent with the field tests the groundwater microcosms showed cis-DCE was more rapidly transformed than TCE. Microcosm tests also indicated that propane inhibited the transformation of cis-DCE and TCE, and as observed in the field, most of the transformation of these compounds occurred after propane was reduced to low concentrations. In the field demonstration propane utilization rates and rates of CAH removal slowed after three to four months of repeated propane additions, which coincided with the depletion of nitrogen (as nitrate) in the treatment zone. Similar results were obtained with repeated additions of propane to the microcosms. In the field test ammonia was added to the propane/air mixture to provide a

  18. SLS-1: The first dedicated life sciences shuttle flight

    NASA Astrophysics Data System (ADS)

    Phillips, Robert W.

    1992-05-01

    Spacelab Life Sciences 1 was the first space laboratory dedicated to life science research. It was launched into orbit in early June 1991 aboard the space shuttle Columbia. The data from this flight have greatly expanded our knowledge of the effects of microgravity on human physiology as data were collected in-flight, not just pre and post. Principal goals of the mission were the measurement of rapid and semichronic (8 days) changes in the cardiovascular and cardiopulmonary systems during the flight and then to measure the rate of readaptation following return to Earth. Results from the four teams involved in that research will be presented in this panel. In addition to the cardiovascular-cardiopulmonary research, extensive metabolic studies encompassed fluid, electrolyte and energy balance, renal function, hematology and musculoskeletal changes. Finally, the crew participated in several neurovestibular studies. Overall, the mission was an outstanding success and has provided much new information on the lability of human responses to the space environment.

  19. Dedicated education unit: implementing an innovation in replication sites.

    PubMed

    Moscato, Susan R; Nishioka, Vicki M; Coe, Michael T

    2013-05-01

    An important measure of an innovation is the ease of replication and achievement of the same positive outcomes. The dedicated education unit (DEU) clinical education model uses a collaborative academic-service partnership to develop an optimal learning environment for students. The University of Portland adapted this model from Flinders University, Australia, to increase the teaching capacity and quality of nursing education. This article identifies DEU implementation essentials and reports on the outcomes of two replication sites that received consultation support from the University of Portland. Program operation information, including education requirements for clinician instructors, types of patient care units, and clinical faculty-to-student ratios is presented. Case studies of the three programs suggest the DEU model is adaptable to a range of different clinical settings and continues to show promise as one strategy for addressing the nurse faculty shortage and strengthening academic-clinical collaborations while maintaining quality clinical education for students.

  20. Development of new Hopkinson's device dedicated to rib's bone characterisation

    NASA Astrophysics Data System (ADS)

    Mayeur, O.; Haugou, G.; Chaâri, F.; Delille, R.; Drazetic, P.; Markiewicz, E.

    2012-08-01

    This study presents an original approach for the design of adapted Hopkinson device dedicated to the characterisation of human ribs' cortical bone. The quasi-static study carried out on flat samples coming from this anatomical part highlighted the importance of the critical effect of sample shape and location on the accuracy of identify mechanical behaviour. The access to higher rates of strains, Hopkinson bars technique are classically required whatever compression or tension loadings. Classical designs of measurement bars are not suitable for this purpose due to the complexity of specimen's geometry (thickness variation). In this context, a new design of SHTB is studied here on the basis on a Finite Element approach of the set measurement bars/biological coupon. Finite Element simulations have been conducted using Abaqus explicit code by varying the design configuration. The comparison on input and output elastic waves suggests a set of small diameter bars in polyamide 66 for a better signal measurement.

  1. Dedicated contamination experiments in the Orion laser target chamber

    NASA Astrophysics Data System (ADS)

    Andrew, J.; Chevalier, J.-M.; Egan, D.; Geille, A.; Jadaud, J.-P.; Quessada, J.-H.; Raffestin, D.; Rubery, M.; Treadwell, P.; Videau, L.

    2015-11-01

    The use of solid targets irradiated in a vacuum target chamber by focussed high energy, high power laser beams to study the properties of matter at high densities, pressures and temperatures are well known. An undesirable side effect of these interactions is the generation of plumes of solid, liquid and gaseous matter which move away from the target and coat or physically damage surfaces within the target chamber. The largest aperture surfaces in these chambers are usually the large, high specification optical components used to produce the extreme conditions being studied [e.g. large aperture off axis parabolas, aspheric lenses, X ray optics and planar debris shields]. In order to study these plumes and the effects that they produce a set of dedicated experiments were performed to evaluate target by product coating distributions and particle velocities by a combined diagnostic instrument that utilised metal witness plates, polymer witness plates, fibre velocimetry and low density foam particle catchers.

  2. SLS-1: The first dedicated life sciences shuttle flight

    NASA Technical Reports Server (NTRS)

    Phillips, Robert W.

    1992-01-01

    Spacelab Life Sciences 1 was the first space laboratory dedicated to life science research. It was launched into orbit in early June 1991 aboard the space shuttle Columbia. The data from this flight have greatly expanded our knowledge of the effects of microgravity on human physiology as data were collected in-flight, not just pre and post. Principal goals of the mission were the measurement of rapid and semichronic (8 days) changes in the cardiovascular and cardiopulmonary systems during the flight and then to measure the rate of readaptation following return to Earth. Results from the four teams involved in that research will be presented in this panel. In addition to the cardiovascular-cardiopulmonary research, extensive metabolic studies encompassed fluid, electrolyte and energy balance, renal function, hematology and musculoskeletal changes. Finally, the crew participated in several neurovestibular studies. Overall, the mission was an outstanding success and has provided much new information on the lability of human responses to the space environment.

  3. Commercialization of willow bioenergy - a dedicated feedstock supply system

    SciTech Connect

    White, E.H.; Abrahamson, L.P.; Robison, D.J.

    1995-11-01

    Willow hybrids grown as a Dedicated Feedstock Supply System (DFSS) have been analyzed and found to be a feasibile means of augmenting current coal and natural gas resources for power generation. This study focused on the technology and infrastructure required to grow willow DFSS and integrate it with four existing pulverized coal electric generation facilities in central and western New York. The study found that both utilities and growers can forge a long-term business relationship that offers fuel diversity, fuel cost competitiveness and environmental benefits for the utility partners while reinvigorating central and western New York business in the agricultural sector. Growers can bring idle land and land being farmed at a loss back into profitable production while reducing environmental impacts associated with more traditional row crops. The Consortium is gearing up to put in place the growers contracts and the acreage necessary to take the first steps to prove and develop a major new business opportunity for rural New York.

  4. Spacelab mission 4 - The first dedicated life sciences mission

    NASA Technical Reports Server (NTRS)

    Perry, T. W.; Reid, D. H.

    1983-01-01

    Plans for the first Spacelab-4 mission dedicated entirely to the life sciences, are reviewed. The thrust of the scientific mission scheduled for late 1985 will be to study the acute effects of weightlessness on living systems, particularly humans. The payload of the Spacelab compartment will contain 24 experiments of which approximately half will involve humans. Among the major areas of interest are cardiovascular and pulmonary function, vestibular function, renal and endocrine physiology, hematology, nitrogen balance, immunological function, the gravitational biology of plants, inflight fertilization of frogs' eggs and the effects of zero gravity on monkeys and rats. In selecting the array of experiments an effort was made to combine investigations with complementary scientific objectives to develop animal models of human biological problems.

  5. A dedicated undergraduate gynaecology teaching clinic: The Keele experience.

    PubMed

    Katali, Hamza Mahamadu; Parry-Smith, William Rhys; Eliot, Rees L; O'Mahony, Fidelma

    2016-01-01

    Much discussion in the literature centres on how best to teach medical students the intricacies of gynaecological assessment and the subsequent formulation of a management plan. At Keele University skills are initially developed in a simulated setting and then transferred to the workplace where students continue to develop their skills. A dedicated undergraduate gynaecology teaching clinic has been developed and comprises of 2-3 students and a tutor. All 38 students rotating through the department between January and June 2013 were invited to complete an anonymous questionnaire to evaluate this clinic and 36 (95%) of them responded. Respondents felt significantly more comfortable taking a gynaecology history, ensuring privacy during examination and formulating a management plan post-clinic (all p < 0.001), with female students feeling significantly more comfortable than their male counterparts (p = 0.04). The use of this clinic shows great promise to help students learn an unfamiliar and challenging skill.

  6. Neural-network dedicated processor for solving competitive assignment problems

    NASA Technical Reports Server (NTRS)

    Eberhardt, Silvio P. (Inventor)

    1993-01-01

    A neural-network processor for solving first-order competitive assignment problems consists of a matrix of N x M processing units, each of which corresponds to the pairing of a first number of elements of (R sub i) with a second number of elements (C sub j), wherein limits of the first number are programmed in row control superneurons, and limits of the second number are programmed in column superneurons as MIN and MAX values. The cost (weight) W sub ij of the pairings is programmed separately into each PU. For each row and column of PU's, a dedicated constraint superneuron insures that the number of active neurons within the associated row or column fall within a specified range. Annealing is provided by gradually increasing the PU gain for each row and column or increasing positive feedback to each PU, the latter being effective to increase hysteresis of each PU or by combining both of these techniques.

  7. The dedicated education unit: a practice and education partnership.

    PubMed

    Miller, Terry W

    2005-01-01

    Both educational institutions and health care agencies have a propensity to look to the past for solutions to their present and projected problems, such as the nursing shortage. One problem that continually surfaces and has become one of two primary limitations on expanding nursing school enrollments is finding and sustaining quality clinical experiences in acute care settings. The demand for these clinical sites continues to grow and the consequent need for effective clinical partnerships grows with it. The Dedicated Education Unit is a creative strategy for addressing the confluence of highly sophisticated marketing efforts promoting the profession of nursing as a whole, the high demand job market for nurses, and the increase in nursing school enrollments at both undergraduate and graduate levels.

  8. Separate, dedicated care teams for living organ donors.

    PubMed

    McQuarrie, Brenda; Gordon, Debra

    2003-06-01

    Living donation is an increasingly common option offered to patients in most transplant programs. Staff involved in the education, assessment, and care of this patient group is faced with increasingly complicated assessments both medically and psychologically. Supporting arguments for dedicated care teams for living organ donors include the large number of transplantations performed using living donors, the continued need to promote living organ donation, and the growing complexity of both medical and psychological factors in donor assessments. In addition, there is a need to implement the standards proposed by the 2000 Consensus Group, as well as to develop a body of evidence-based research related both to short- and long-term issues for this patient group. The ethical issues related to simultaneous involvement with both donors and recipients, and a need to ensure confidentiality are additional supporting arguments for the need to provide separate care providers for donors and recipients.

  9. Life Cycle Analysis of Dedicated Nano-Launch Technologies

    NASA Technical Reports Server (NTRS)

    Zapata, Edgar; McCleskey, Carey; Martin, John; Lepsch, Roger; Hernani, Tosoc

    2014-01-01

    Recent technology advancements have enabled the development of small cheap satellites that can perform useful functions in the space environment. Currently, the only low cost option for getting these payloads into orbit is through ride share programs. As a result, these launch opportunities await primary payload launches and a backlog exists. An alternative option would be dedicated nano-launch systems built and operated to provide more flexible launch services, higher availability, and affordable prices. The potential customer base that would drive requirements or support a business case includes commercial, academia, civil government and defense. Further, NASA technology investments could enable these alternative game changing options.With this context, in 2013 the Game Changing Development (GCD) program funded a NASA team to investigate the feasibility of dedicated nano-satellite launch systems with a recurring cost of less than $2 million per launch for a 5 kg payload to low Earth orbit. The team products would include potential concepts, technologies and factors for enabling the ambitious cost goal, exploring the nature of the goal itself, and informing the GCD program technology investment decision making process. This paper provides an overview of the life cycle analysis effort that was conducted in 2013 by an inter-center NASA team. This effort included the development of reference nano-launch system concepts, developing analysis processes and models, establishing a basis for cost estimates (development, manufacturing and launch) suitable to the scale of the systems, and especially, understanding the relationship of potential game changing technologies to life cycle costs, as well as other factors, such as flights per year.

  10. Life Cycle Analysis of Dedicated Nano-Launch Technologies

    NASA Technical Reports Server (NTRS)

    Zapata, Edgar; McCleskey, Carey (Editor); Martin, John; Lepsch, Roger; Ternani, Tosoc

    2014-01-01

    Recent technology advancements have enabled the development of small cheap satellites that can perform useful functions in the space environment. Currently, the only low cost option for getting these payloads into orbit is through ride share programs - small satellites awaiting the launch of a larger satellite, and then riding along on the same launcher. As a result, these small satellite customers await primary payload launches and a backlog exists. An alternative option would be dedicated nano-launch systems built and operated to provide more flexible launch services, higher availability, and affordable prices. The potential customer base that would drive requirements or support a business case includes commercial, academia, civil government and defense. Further, NASA technology investments could enable these alternative game changing options. With this context, in 2013 the Game Changing Development (GCD) program funded a NASA team to investigate the feasibility of dedicated nano-satellite launch systems with a recurring cost of less than $2 million per launch for a 5 kg payload to low Earth orbit. The team products would include potential concepts, technologies and factors for enabling the ambitious cost goal, exploring the nature of the goal itself, and informing the GCD program technology investment decision making process. This paper provides an overview of the life cycle analysis effort that was conducted in 2013 by an inter-center NASA team. This effort included the development of reference nano-launch system concepts, developing analysis processes and models, establishing a basis for cost estimates (development, manufacturing and launch) suitable to the scale of the systems, and especially, understanding the relationship of potential game changing technologies to life cycle costs, as well as other factors, such as flights per year.

  11. Environmental Sciences Laboratory dedication, February 26-27, 1979

    SciTech Connect

    Auerbach, S.I.; Millemann, N.T.

    1980-09-01

    The dedication of the new Environmental Sciences Laboratory coincided with the 25th year of the establishment of the science of ecology at Oak Ridge National Laboratory. That quarter century witnessed the evolution of ecology from an obscure, backwater discipline of biology to a broadly used, everyday household word. The transition reflected broad and basic changes in our social and cultural view of the world. This was brought about as a result of the awareness developed in our society of the importance of the environment, coupled with efforts of ecologists and other environmental scientists who identified, clarified, and formulated the issues and challenges of environmental protection for both the lay public and the scientific community. In many respects, the activities in ecology at ORNL were a microcosm of the broader social scene; the particular problems of the environment associated with atomic energy needed to be defined in scientific terms and articulated in both the specific and general sense for a larger audience which was unfamiliar with the field and somewhat alien to its concepts and philosophy. The success of this effort is reflected in the existence of the new Environmental Sciences Laboratory. This dedication volume brings together the thoughts and reflections of many of these scientists whose efforts contributed in a unique and individualistic fashion not only to ORNL but also to the national identification of ecology and its importance to the achievement of our national goals. Their remarks and presentations are not only a pleasant and personally gratifying recapitulation of the past and of ORNL's contributions to ecology but also portend some of the challenges to ecology in the future.

  12. Quantification with a dedicated breast PET/CT scanner

    PubMed Central

    Bowen, Spencer L.; Ferrero, Andrea; Badawi, Ramsey D.

    2012-01-01

    Purpose: Dedicated breast PET/CT is expected to have utility in local staging, surgical planning, monitoring of therapy response, and detection of residual disease for breast cancer. Quantitative metrics will be integral to several such applications. The authors present a validation of fully 3D data correction schemes for a custom built dedicated breast PET/CT (DbPET/CT) scanner via 18F-FDG phantom scans. Methods: A component-based normalization was implemented, live-time was estimated with a multicomponent model, and a variance reduced randoms estimate was computed from delayed coincidences. Attenuation factors were calculated by using a CT based segmentation scheme while scatter was computed using a Monte Carlo (MC) simulation method. As no performance standard currently exists for breast PET systems, custom performance tests were created based on prior patient imaging results. Count-rate linearity for live-time and randoms corrections was measured with a decay experiment for a solid polyethylene cylinder phantom with an offset line source. A MC simulation was used to validate attenuation correction, a multicompartment phantom with asymmetric activity distribution provided an assessment of scatter correction, and image uniformity after geometric and detector normalization was measured from a high count scan of a uniform cylinder phantom. Raw data were reconstructed with filtered back projection (FBP) after Fourier rebinning. To quantify performance absolute activity concentrations, contrast recovery coefficients and image uniformity were calculated through region of interest analysis. Results: The most significant source of error was attributed to mispositioning of events due to pile-up, presenting in count-related axial and transaxial nonuniformities that were not corrected for with the normalization method used here. Within the range of singles counts observed during clinical trials residual error after applying all corrections was comparable to that of a

  13. Dedicated Cone-Beam CT System for Extremity Imaging

    PubMed Central

    Al Muhit, Abdullah; Zbijewski, Wojciech; Thawait, Gaurav K.; Stayman, J. Webster; Packard, Nathan; Senn, Robert; Yang, Dong; Foos, David H.; Yorkston, John; Siewerdsen, Jeffrey H.

    2014-01-01

    Purpose To provide initial assessment of image quality and dose for a cone-beam computed tomographic (CT) scanner dedicated to extremity imaging. Materials and Methods A prototype cone-beam CT scanner has been developed for imaging the extremities, including the weight-bearing lower extremities. Initial technical assessment included evaluation of radiation dose measured as a function of kilovolt peak and tube output (in milliampere seconds), contrast resolution assessed in terms of the signal difference–to-noise ratio (SDNR), spatial resolution semiquantitatively assessed by using a line-pair module from a phantom, and qualitative evaluation of cadaver images for potential diagnostic value and image artifacts by an expert CT observer (musculoskeletal radiologist). Results The dose for a nominal scan protocol (80 kVp, 108 mAs) was 9 mGy (absolute dose measured at the center of a CT dose index phantom). SDNR was maximized with the 80-kVp scan technique, and contrast resolution was sufficient for visualization of muscle, fat, ligaments and/or tendons, cartilage joint space, and bone. Spatial resolution in the axial plane exceeded 15 line pairs per centimeter. Streaks associated with x-ray scatter (in thicker regions of the patient—eg, the knee), beam hardening (about cortical bone—eg, the femoral shaft), and cone-beam artifacts (at joint space surfaces oriented along the scanning plane—eg, the interphalangeal joints) presented a slight impediment to visualization. Cadaver images (elbow, hand, knee, and foot) demonstrated excellent visibility of bone detail and good soft-tissue visibility suitable to a broad spectrum of musculoskeletal indications. Conclusion A dedicated extremity cone-beam CT scanner capable of imaging upper and lower extremities (including weight-bearing examinations) provides sufficient image quality and favorable dose characteristics to warrant further evaluation for clinical use. © RSNA, 2013 Online supplemental material is available for

  14. Enabling Dedicated, Affordable Space Access Through Aggressive Technology Maturation

    NASA Technical Reports Server (NTRS)

    Jones, Jonathan; Kibbey, Tim; Lampton, Pat; Brown, Thomas

    2014-01-01

    A recent explosion in nano-sat, small-sat, and university class payloads has been driven by low cost electronics and sensors, wide component availability, as well as low cost, miniature computational capability and open source code. Increasing numbers of these very small spacecraft are being launched as secondary payloads, dramatically decreasing costs, and allowing greater access to operations and experimentation using actual space flight systems. While manifesting as a secondary payload provides inexpensive rides to orbit, these arrangements also have certain limitations. Small, secondary payloads are typically included with very limited payload accommodations, supported on a non interference basis (to the prime payload), and are delivered to orbital conditions driven by the primary launch customer. Integration of propulsion systems or other hazardous capabilities will further complicate secondary launch arrangements, and accommodation requirements. The National Aeronautics and Space Administration's Marshall Space Flight Center has begun work on the development of small, low cost launch system concepts that could provide dedicated, affordable launch alternatives to small, risk tolerant university type payloads and spacecraft. These efforts include development of small propulsion systems and highly optimized structural efficiency, utilizing modern advanced manufacturing techniques. This paper outlines the plans and accomplishments of these efforts and investigates opportunities for truly revolutionary reductions in launch and operations costs. Both evolution of existing sounding rocket systems to orbital delivery, and the development of clean sheet, optimized small launch systems are addressed. A launch vehicle at the scale and price point which allows developers to take reasonable risks with new propulsion and avionics hardware solutions does not exist today. Establishing this service provides a ride through the proverbial "valley of death" that lies between

  15. In situ (1)H and (13)C MAS NMR kinetic study of the mechanism of H/D exchange for propane on zeolite H-ZSM-5.

    PubMed

    Arzumanov, Sergei S; Reshetnikov, Sergei I; Stepanov, Alexander G; Parmon, Valentin N; Freude, Dieter

    2005-10-27

    The kinetics of hydrogen (H/D) exchange between Brønsted acid sites of zeolite H-ZSM-5 and variously deuterated propanes (propane-d(8), propane-1,1,1,3,3,3-d(6), propane-2,2-d(2)) have been monitored in situ by (1)H MAS NMR spectroscopy within the temperature range of 503-556 K. The contribution of intramolecular hydrogen transfer to the H/D exchange in the adsorbed propane was estimated by monitoring the kinetics of (13)C-labeled carbon scrambling in propane-2-(13)C in situ with (13)C MAS NMR at 543-573 K. Possible mechanisms of the exchange have been verified on the basis of the analysis of the variation of protium concentration in both the methyl and the methylene groups of propane in dependence of the reaction time. The main route of the exchange consists of a direct exchange of the acidic OH groups of the zeolite with either the methyl groups or the methylene group presumably with a pentacoordinated carbonium ion intermediate. The assumption that the intramolecular H scrambling between the methyl groups and the methylene group of propane via carbenium-ion-type intermediates is the fastest process among the other possible routes does not account for the experimental kinetics of H/D exchange for propanes with different initial contents and locations of deuterium in a propane molecule. The rate constant (k(3)) for intramolecular H/D exchange between the methyl and the methylene groups is 4-5 times lower compared to those of the direct exchange of both the methyl (k(1)) and the methylene (k(2)) groups with Brønsted acid sites of the zeolite, the k(1) being ca. 1.5 times higher than k(2). At lower temperature (473 K), the exchange is slower, and the expected difference between k(1) and k(2) is more essential, k(1) = 3k(2). This accounts for earlier observed regioselectivity of the exchange for propane on H-ZSM-5 at 473 K. Faster direct exchange with the methyl groups compared to that with the methylene groups was attributed to a possible, more spatial

  16. Investigation of statistical iterative reconstruction for dedicated breast CT

    SciTech Connect

    Makeev, Andrey; Glick, Stephen J.

    2013-08-15

    Purpose: Dedicated breast CT has great potential for improving the detection and diagnosis of breast cancer. Statistical iterative reconstruction (SIR) in dedicated breast CT is a promising alternative to traditional filtered backprojection (FBP). One of the difficulties in using SIR is the presence of free parameters in the algorithm that control the appearance of the resulting image. These parameters require tuning in order to achieve high quality reconstructions. In this study, the authors investigated the penalized maximum likelihood (PML) method with two commonly used types of roughness penalty functions: hyperbolic potential and anisotropic total variation (TV) norm. Reconstructed images were compared with images obtained using standard FBP. Optimal parameters for PML with the hyperbolic prior are reported for the task of detecting microcalcifications embedded in breast tissue.Methods: Computer simulations were used to acquire projections in a half-cone beam geometry. The modeled setup describes a realistic breast CT benchtop system, with an x-ray spectra produced by a point source and an a-Si, CsI:Tl flat-panel detector. A voxelized anthropomorphic breast phantom with 280 μm microcalcification spheres embedded in it was used to model attenuation properties of the uncompressed woman's breast in a pendant position. The reconstruction of 3D images was performed using the separable paraboloidal surrogates algorithm with ordered subsets. Task performance was assessed with the ideal observer detectability index to determine optimal PML parameters.Results: The authors' findings suggest that there is a preferred range of values of the roughness penalty weight and the edge preservation threshold in the penalized objective function with the hyperbolic potential, which resulted in low noise images with high contrast microcalcifications preserved. In terms of numerical observer detectability index, the PML method with optimal parameters yielded substantially improved

  17. Dedicated breast CT: Fibroglandular volume measurements in a diagnostic population

    SciTech Connect

    Vedantham, Srinivasan; Shi Linxi; Karellas, Andrew; O'Connell, Avice M.

    2012-12-15

    Purpose: To determine the mean and range of volumetric glandular fraction (VGF) of the breast in a diagnostic population using a high-resolution flat-panel cone-beam dedicated breast CT system. This information is important for Monte Carlo-based estimation of normalized glandular dose coefficients and for investigating the dependence of VGF on breast dimensions, race, and pathology. Methods: Image data from a clinical trial investigating the role of dedicated breast CT that enrolled 150 women were retrospectively analyzed to determine the VGF. The study was conducted in adherence to a protocol approved by the institutional human subjects review boards and written informed consent was obtained from all study participants. All participants in the study were assigned BI-RADS{sup Registered-Sign} 4 or 5 as per the American College of Radiology assessment categories after standard diagnostic work-up and underwent dedicated breast CT exam prior to biopsy. A Gaussian-kernel based fuzzy c-means algorithm was used to partition the breast CT images into adipose and fibroglandular tissue after segmenting the skin. Upon determination of the accuracy of the algorithm with a phantom, it was applied to 137 breast CT volumes from 136 women. VGF was determined for each breast and the mean and range were determined. Pathology results with classification as benign, malignant, and hyperplasia were available for 132 women, and were used to investigate if the distributions of VGF varied with pathology. Results: The algorithm was accurate to within {+-}1.9% in determining the volume of an irregular shaped phantom. The study mean ({+-} inter-breast SD) for the VGF was 0.172 {+-} 0.142 (range: 0.012-0.719). VGF was found to be negatively correlated with age, breast dimensions (chest-wall to nipple length, pectoralis to nipple length, and effective diameter at chest-wall), and total breast volume, and positively correlated with fibroglandular volume. Based on pathology, pairwise statistical

  18. Investigation of statistical iterative reconstruction for dedicated breast CT

    PubMed Central

    Makeev, Andrey; Glick, Stephen J.

    2013-01-01

    Purpose: Dedicated breast CT has great potential for improving the detection and diagnosis of breast cancer. Statistical iterative reconstruction (SIR) in dedicated breast CT is a promising alternative to traditional filtered backprojection (FBP). One of the difficulties in using SIR is the presence of free parameters in the algorithm that control the appearance of the resulting image. These parameters require tuning in order to achieve high quality reconstructions. In this study, the authors investigated the penalized maximum likelihood (PML) method with two commonly used types of roughness penalty functions: hyperbolic potential and anisotropic total variation (TV) norm. Reconstructed images were compared with images obtained using standard FBP. Optimal parameters for PML with the hyperbolic prior are reported for the task of detecting microcalcifications embedded in breast tissue. Methods: Computer simulations were used to acquire projections in a half-cone beam geometry. The modeled setup describes a realistic breast CT benchtop system, with an x-ray spectra produced by a point source and an a-Si, CsI:Tl flat-panel detector. A voxelized anthropomorphic breast phantom with 280 μm microcalcification spheres embedded in it was used to model attenuation properties of the uncompressed woman's breast in a pendant position. The reconstruction of 3D images was performed using the separable paraboloidal surrogates algorithm with ordered subsets. Task performance was assessed with the ideal observer detectability index to determine optimal PML parameters. Results: The authors' findings suggest that there is a preferred range of values of the roughness penalty weight and the edge preservation threshold in the penalized objective function with the hyperbolic potential, which resulted in low noise images with high contrast microcalcifications preserved. In terms of numerical observer detectability index, the PML method with optimal parameters yielded substantially improved

  19. Temporal subtraction contrast-enhanced dedicated breast CT

    NASA Astrophysics Data System (ADS)

    Gazi, Peymon M.; Aminololama-Shakeri, Shadi; Yang, Kai; Boone, John M.

    2016-09-01

    The development of a framework of deformable image registration and segmentation for the purpose of temporal subtraction contrast-enhanced breast CT is described. An iterative histogram-based two-means clustering method was used for the segmentation. Dedicated breast CT images were segmented into background (air), adipose, fibroglandular and skin components. Fibroglandular tissue was classified as either normal or contrast-enhanced then divided into tiers for the purpose of categorizing degrees of contrast enhancement. A variant of the Demons deformable registration algorithm, intensity difference adaptive Demons (IDAD), was developed to correct for the large deformation forces that stemmed from contrast enhancement. In this application, the accuracy of the proposed method was evaluated in both mathematically-simulated and physically-acquired phantom images. Clinical usage and accuracy of the temporal subtraction framework was demonstrated using contrast-enhanced breast CT datasets from five patients. Registration performance was quantified using normalized cross correlation (NCC), symmetric uncertainty coefficient, normalized mutual information (NMI), mean square error (MSE) and target registration error (TRE). The proposed method outperformed conventional affine and other Demons variations in contrast enhanced breast CT image registration. In simulation studies, IDAD exhibited improvement in MSE (0-16%), NCC (0-6%), NMI (0-13%) and TRE (0-34%) compared to the conventional Demons approaches, depending on the size and intensity of the enhancing lesion. As lesion size and contrast enhancement levels increased, so did the improvement. The drop in the correlation between the pre- and post-contrast images for the largest enhancement levels in phantom studies is less than 1.2% (150 Hounsfield units). Registration error, measured by TRE, shows only submillimeter mismatches between the concordant anatomical target points in all patient studies. The algorithm was

  20. Measurements of Rate Coefficients for Reactions of OH with Ethanol and Propan-2-ol at Very Low Temperatures.

    PubMed

    Caravan, Rebecca L; Shannon, Robin J; Lewis, Thomas; Blitz, Mark A; Heard, Dwayne E

    2015-07-16

    The low temperature kinetics of the reactions of OH with ethanol and propan-2-ol have been studied using a pulsed Laval nozzle apparatus coupled with pulsed laser photolysis-laser-induced fluorescence (PLP-LIF) spectroscopy. The rate coefficients for both reactions have been found to increase significantly as the temperature is lowered, by approximately a factor of 18 between 293 and 54 K for ethanol, and by ∼10 between 298 and 88 K for OH + propan-2-ol. The pressure dependence of the rate coefficients provides evidence for two reaction channels: a zero pressure bimolecular abstraction channel leading to products and collisional stabilization of a weakly bound OH-alcohol complex. The presence of the abstraction channel at low temperatures is rationalized by a quantum mechanical tunneling mechanism, most likely through the barrier to hydrogen abstraction from the OH moiety on the alcohol.

  1. Flame behaviors of propane/air premixed flame propagation in a closed rectangular duct with a 90-deg bend

    NASA Astrophysics Data System (ADS)

    He, Xuechao; Sun, Jinhua; Yuen, K. K.; Ding, Yibin; Chen, Sining

    2008-11-01

    Experiments of flame propagation in a small, closed rectangular duct with a 90° bend were performed for a propane-air mixture. The high speed camera and Schlieren techniques were used to record images of flame propagation process in the combustion pipe. Meanwhile, the fine thermocouples and ion current probes were applied to measure the temperature distribution and reaction intensity of combustion. The characteristics of propane-air flame and its microstructure were analyzed in detail by the experimental results. In the test, the special tulip flame formation was observed. Around the bend, the flame tip proceeded more quickly at the lower side with the flame front elongated toward the axial direction. And transition to turbulent flame occurred. It was suggested that fluctuations of velocity, ion current and temperature were mainly due to the comprehensive effects of multi-wave and the intense of turbulent combustion.

  2. Intermolecular hydrogen transfer between guest species in small and large cages of methane + propane mixed gas hydrates.

    PubMed

    Sugahara, Takeshi; Kobayashi, Yusuke; Tani, Atsushi; Inoue, Tatsuya; Ohgaki, Kazunari

    2012-03-15

    To investigate the molecular interaction between guest species inside of the small and large cages of methane + propane mixed gas hydrates, thermal stabilities of the methyl radical (possibly induced in small cages) and the normal propyl and isopropyl radicals (induced in large cages) were investigated by means of electron spin resonance measurements. The increase of the total amount of the normal propyl and isopropyl radicals reveals that the methyl radical in the small cage withdraws one hydrogen atom from the propane molecule enclathrated in the adjacent large cage of the structure-II hydrate. A guest species in a hydrate cage has the ability to interact closely with the other one in the adjacent cages. The clathrate hydrate may be utilized as a possible nanoscale reaction field.

  3. Use of propane as a quench gas in argon-filled proportional counters and comparison with other quench gases

    NASA Technical Reports Server (NTRS)

    Agrawal, P. C.; Ramsey, B. D.

    1988-01-01

    An experimental investigation of propane and six other quench gases was carried out in argon-filled proportional counters. The objective of the study was to find the best gas mixture for optimizing the gas gain and the energy resolution as well as to understand the role of the ionization potential of quench gases in determining these parameters. It was found that the best gas gains and energy resolutions are obtained with propane, ethane, and isobutane in that order. The ionization potentials of these three lie below the argon metastable potentials and have the lowest value of resonance defect compared to the other quench gases. The better results obtained with these mixtures can be explained by an increased ionization yield resulting from the Penning effect. Propylene and trans-2-butene give inferior performance compared to the above three gases. Methane and carbon dioxide, the most commonly used quench gases in the argon-filled detectors, provide the worst results.

  4. Effect of Initial Mixture Temperature on Flame Speed of Methane-Air, Propane-Air, and Ethylene-Air Mixtures

    NASA Technical Reports Server (NTRS)

    Dugger, Gordon L

    1952-01-01

    Flame speeds based on the outer edge of the shadow cast by the laminar Bunsen cone were determined as functions of composition for methane-air mixtures at initial mixture temperatures ranging from -132 degrees to 342 degrees c and for propane-air and ethylene-air mixtures at initial mixture temperatures ranging from -73 degrees to 344 degrees c. The data showed that maximum flame speed increased with temperature at an increasing rate. The percentage change in flame speed with change in initial temperature for the three fuels followed the decreasing order, methane, propane, and ethylene. Empirical equations were determined for maximum flame speed as a function of initial temperature over the temperature range covered for each fuel. The observed effect of temperature on flame speed for each of the fuels was reasonably well predicted by either the thermal theory as presented by Semenov or the square-root law of Tanford and Pease.

  5. The Effects of Supercritical Propane on the Alkylation of Toluene with Ethylene over USY and Sulfated Zirconia Catalysts

    SciTech Connect

    Ginosar, Daniel Michael; Burch, Kyle Coates; Thompson, David Neal

    2002-11-01

    The alkylation of toluene with ethylene over microporous USY zeolite and mesoporous sulfated zirconia (S/ZrO2) catalysts was explored at liquid, near-critical liquid, and supercritical conditions using propane as the supercritical cosolvent. Liquid, near-critical liquid, and supercritical conditions were examined for their effects on product selectivity and catalyst activity maintenance. The S/ZrO2 catalyst demonstrated alkylation activity almost exclusively, whereas the USY catalyst demonstrated both alkylation and cracking/disproportionation activities. Near-critical and supercritical reaction conditions improved product selectivity with the USY catalyst through the suppression of disproportionation reactions and enhanced ortho- and para-ethyltoluene selectivity. However, the addition of the supercritical cosolvent resulted in increased deactivation for both the S/ZrO2 and USY catalysts, with deactivation increasing with propane mole fraction.

  6. Three-phase equilibria in the binary system ethylene + eicosane and the ternary system propane + ethylene + eicosane

    SciTech Connect

    Gregorowicz, J.; Loos, T.W. de; Arons, J. . Lab. of Applied Thermodyanamics and Phase Equilibria)

    1993-07-01

    The solid eicosane-liquid-vapor (SLV) phase behavior in the binary system ethylene + eicosane was investigated. It was found that the SLV curve ends at a critical end point where liquid and vapor are critical in the presence of pure solid eicosane. In this binary system liquid-liquid-vapor (LLV) equilibria are metastable with respect to solid formation. Addition of propane to mixtures of ethylene and eicosane revealed stable LLV equlibria. P-T sections for seven ternary mixtures with different propane and eicosane concentrations were determined according to the synthetic method. On the basis of the results obtained, a rough estimate of the ternary tricritical point and the metastable binary LLV curve is performed.

  7. Rural model dedicated education unit: partnership between college and hospital.

    PubMed

    Harmon, Lisa M

    2013-02-01

    This article describes the pilot project development of a rural model Dedicated Education Unit (DEU) by a rural college nursing program and a rural hospital to increase student nurses' confidence and proficiency and improve recruitment of prepared rural staff nurses. Traditionally, for economies of scale, most student clinical rotations occurred in urban settings with the number of students per clinical instructor allowed by the state board of nursing. College budget constraints negated the placement of fewer than this mandated maximum number of students in a rural hospital with a clinical instructor; moreover, rural hospitals could not accommodate 10 students at one time. Rural nursing students were anxious in the urban settings, and this anxiety precluded learning in many instances. Rural hospitals face higher registered nurse vacancies than urban centers. Of the nurses applying for open positions, many were not prepared for the demands of rural nursing, resulting in increased turnover and high orientation costs. The rural model DEU addressed issues of both the nursing program and the hospital. The design and development of the rural model DEU and the advantages of the partnership for the college nursing program and the hospital are discussed. Initial outcomes and serendipitous findings from the pilot project are also discussed.

  8. CIRCE: A dedicated storage ring for coherent THz synchrotron radiation

    SciTech Connect

    Byrd, J.M.; Martin, Michael C.; McKinney, W.R.; Munson, D.V.; Nishimura, H.; Robin, D.S.; Sannibale, F.; Schlueter, R.D.; Thur, W.G.; Jung, J.Y.; Wan, W.

    2003-08-12

    We present the concepts for an electron storage ring dedicated to and optimized for the production of stable coherent synchrotron radiation (CSR) over the far-infrared terahertz wavelength range from 200 mm to about one cm. CIRCE (Coherent InfraRed CEnter) will be a 66 m circumference ring located on top of the ALS booster synchrotron shielding tunnel and using the existing ALS injector. This location provides enough floor space for both the CIRCE ring, its required shielding, and numerous beamlines. We briefly outline a model for CSR emission in which a static bunch distortion induced by the synchrotron radiation field is used to significantly extend the stable CSR emission towards higher frequencies. This model has been verified with experimental CSR results. We present the calculated CIRCE photon flux where a gain of 6-9 orders of magnitude is shown compared to existing far-IR sources. Additionally, the particular design of the dipole vacuum chamber has been optimized to allow an excellent transmission of these far-infrared wavelengths. We believe that the CIRCE source can be constructed for a modest cost.

  9. Rooftop Unitary Air Conditioner with Integral Dedicated Outdoor Air System

    SciTech Connect

    Tiax Llc

    2006-02-28

    Energy use of rooftop and other unitary air-conditioners in commercial applications accounts for about 1 quad (10{sup 15} Btu) of primary energy use annually in the U.S. [Reference 7]. The realization that this cooling equipment accounts for the majority of commercial building cooled floorspace and the majority also of commercial building energy use has spurred development of improved-efficiency equipment as well as development of stricter standards addressing efficiency levels. Another key market driver affecting design of rooftop air-conditioning equipment has been concern regarding comfort and the control of humidity. Trends for increases in outdoor air ventilation rates in certain applications, and the increasing concern about indoor air quality problems associated with humidity levels and moisture in buildings points to a need for improved dehumidification capability in air-conditioning equipment of all types. In many cases addressing this issue exacerbates energy efficiency, and vice versa. The integrated dedicated outdoor air system configuration developed in this project addresses both energy and comfort/humidity issues.

  10. ACR testing of a dedicated head SPECT unit.

    PubMed

    Sensakovic, William F; Hough, Matthew C; Kimbley, Elizabeth A

    2014-07-08

    Physics testing necessary for program accreditation is rigorously defined by the ACR. This testing is easily applied to most conventional SPECT systems based on gamma camera technology. The inSPira HD is a dedicated head SPECT system based on a rotating dual clamshell design that acquires data in a dual-spiral geometry. The unique geometry and configuration force alterations of the standard ACR physics testing protocol. Various tests, such as intrinsic planar uniformity and/or resolution, do not apply. The Data Spectrum Deluxe Phantom used for conventional SPECT testing cannot fit in the inSPira HD scanner bore, making (currently) unapproved use of the Small Deluxe SPECT Phantom necessary. Matrix size, collimator type, scanning time, reconstruction method, and attenuation correction were all varied from the typically prescribed ACR instructions. Visible spheres, sphere contrast, visible rod groups, uniformity, and root mean square (RMS) noise were measured. The acquired SPECT images surpassed the minimum ACR requirements for both spatial resolution (9.5 mm spheres resolved) and contrast (6.4 mm rod groups resolved). Sphere contrast was generally high. Integral uniformity was 4% and RMS noise was 1.7%. Noise appeared more correlated than in images from a conventional SPECT scanner. Attenuation-corrected images produced from direct CT scanning of the phantom and a manufacturer supplied model of the phantom demonstrated negligible differences.

  11. Technical aspects of extracorporeal ultrafiltration: mechanisms, monitoring and dedicated technology.

    PubMed

    Nalesso, Federico; Garzotto, Francesco; Ronco, Claudio

    2010-01-01

    Fluid overload may occur in patients with heart failure. Further complications may arise when cardiorenal syndromes develop and the kidneys are unable to eliminate the accumulated fluid. Diuretics represent the fist line of treatment, although in some case they may be ineffective or even dangerous for the patient. In these conditions, extracorporeal ultrafiltration may be required. Extracorporeal ultrafiltration can be performed continuously or intermittently, using dedicated machines. The goal is to remove the right amount of fluid without causing hemodynamic instability or further ischemia to the kidneys. For this purpose, special technologies are available and they can be utilized in combination to prevent iatrogenic complications. First of all, a complete analysis of heart and kidney function should be carried out. Then, an evaluation of biomarkers of heart failure and a careful analysis of body fluid composition by bioimpedance vector analysis should be carried out to establish the level of hydration and to guide fluid removal strategies. Last but not least, an adequate extracorporeal technique should be employed to remove excess fluid. Preference should be given to continuous forms of ultrafiltration (slow continuous ultrafiltration, continuous venovenous hemofiltration); these techniques guided by a continuous monitoring of circulating blood volume allow for an adequate restoration of body fluid composition minimizing hemodynamic complications and worsening of renal function especially during episodes of acute decompensated heart failure.

  12. Intelligent Advisory Speed Limit Dedication in Highway Using VANET

    PubMed Central

    Md Noor, Rafidah; Yeo, Hwasoo; Jung, Jason J.

    2014-01-01

    Variable speed limits (VSLs) as a mean for enhancing road traffic safety are studied for decades to modify the speed limit based on the prevailing road circumstances. In this study the pros and cons of VSL systems and their effects on traffic controlling efficiency are summarized. Despite the potential effectiveness of utilizing VSLs, we have witnessed that the effectiveness of this system is impacted by factors such as VSL control strategy used and the level of driver compliance. Hence, the proposed approach called Intelligent Advisory Speed Limit Dedication (IASLD) as the novel VSL control strategy which considers the driver compliance aims to improve the traffic flow and occupancy of vehicles in addition to amelioration of vehicle's travel times. The IASLD provides the advisory speed limit for each vehicle exclusively based on the vehicle's characteristics including the vehicle type, size, and safety capabilities as well as traffic and weather conditions. The proposed approach takes advantage of vehicular ad hoc network (VANET) to accelerate its performance, in the way that simulation results demonstrate the reduction of incident detection time up to 31.2% in comparison with traditional VSL strategy. The simulation results similarly indicate the improvement of traffic flow efficiency, occupancy, and travel time in different conditions. PMID:24999493

  13. Intelligent advisory speed limit dedication in highway using VANET.

    PubMed

    Jalooli, Ali; Shaghaghi, Erfan; Jabbarpour, Mohammad Reza; Noor, Rafidah Md; Yeo, Hwasoo; Jung, Jason J

    2014-01-01

    Variable speed limits (VSLs) as a mean for enhancing road traffic safety are studied for decades to modify the speed limit based on the prevailing road circumstances. In this study the pros and cons of VSL systems and their effects on traffic controlling efficiency are summarized. Despite the potential effectiveness of utilizing VSLs, we have witnessed that the effectiveness of this system is impacted by factors such as VSL control strategy used and the level of driver compliance. Hence, the proposed approach called Intelligent Advisory Speed Limit Dedication (IASLD) as the novel VSL control strategy which considers the driver compliance aims to improve the traffic flow and occupancy of vehicles in addition to amelioration of vehicle's travel times. The IASLD provides the advisory speed limit for each vehicle exclusively based on the vehicle's characteristics including the vehicle type, size, and safety capabilities as well as traffic and weather conditions. The proposed approach takes advantage of vehicular ad hoc network (VANET) to accelerate its performance, in the way that simulation results demonstrate the reduction of incident detection time up to 31.2% in comparison with traditional VSL strategy. The simulation results similarly indicate the improvement of traffic flow efficiency, occupancy, and travel time in different conditions.

  14. First results from the Swarm Dedicated Ionospheric Field Inversion chain

    NASA Astrophysics Data System (ADS)

    Chulliat, A.; Vigneron, P.; Hulot, G.

    2016-06-01

    Data-based modeling of the magnetic field originating in the Earth's ionosphere is challenging due to the multiple timescales involved and the small spatial scales of some of the current systems, especially the equatorial electrojet (EEJ) that flows along the magnetic dip equator. The Dedicated Ionospheric Field Inversion (DIFI) algorithm inverts a combination of Swarm satellite and ground observatory data at mid- to low latitudes and provides models of the solar-quiet (Sq) and EEJ magnetic fields on the ground and at satellite altitude. The basis functions of these models are spherical harmonics in quasi-dipole coordinates and Fourier series describing the 24-, 12-, 8- and 6-h periodicities, as well as the annual and semiannual variations. A 1-D conductivity model of the Earth and a 2-D conductivity model of the oceans and continents are used to separate the primary ionospheric field from its induced counterpart. First results from the DIFI algorithm confirm several well-known features of the seasonal variability and westward drift speed of the Sq current systems. They also reveal a peculiar seasonal variability of the Sq field in the Southern hemisphere and a longitudinal variability reminiscent of the EEJ wave-4 structure in the same hemisphere. These observations suggest that the Sq and EEJ currents might be electrically coupled, but only for some seasons and longitudes and more so in the Southern hemisphere than in the Northern hemisphere.

  15. Dedicated Beamline Facilities for Catalytic Research. Synchrotron Catalysis Consortium (SCC)

    SciTech Connect

    Chen, Jingguang; Frenkel, Anatoly; Rodriguez, Jose; Adzic, Radoslav; Bare, Simon R.; Hulbert, Steve L.; Karim, Ayman; Mullins, David R.; Overbury, Steve

    2015-03-04

    Synchrotron spectroscopies offer unique advantages over conventional techniques, including higher detection sensitivity and molecular specificity, faster detection rate, and more in-depth information regarding the structural, electronic and catalytic properties under in-situ reaction conditions. Despite these advantages, synchrotron techniques are often underutilized or unexplored by the catalysis community due to various perceived and real barriers, which will be addressed in the current proposal. Since its establishment in 2005, the Synchrotron Catalysis Consortium (SCC) has coordinated significant efforts to promote the utilization of cutting-edge catalytic research under in-situ conditions. The purpose of the current renewal proposal is aimed to provide assistance, and to develop new sciences/techniques, for the catalysis community through the following concerted efforts: Coordinating the implementation of a suite of beamlines for catalysis studies at the new NSLS-II synchrotron source; Providing assistance and coordination for catalysis users at an SSRL catalysis beamline during the initial period of NSLS to NSLS II transition; Designing in-situ reactors for a variety of catalytic and electrocatalytic studies; Assisting experimental set-up and data analysis by a dedicated research scientist; Offering training courses and help sessions by the PIs and co-PIs.

  16. Crystal growth methods dedicated to low solubility actinide oxalates

    NASA Astrophysics Data System (ADS)

    Tamain, C.; Arab-Chapelet, B.; Rivenet, M.; Grandjean, S.; Abraham, F.

    2016-04-01

    Two novel crystal growth syntheses dedicated to low solubility actinide-oxalate systems and adapted to glove box handling are described. These methods based on the use of precursors of either actinide metal or oxalic acid have been optimized on lanthanide systems (analogue of actinides(III)) and then assessed on real actinide systems. They allow the synthesis of several actinide oxalate single crystals, Am2(C2O4)3(H2O)3·xH2O, Th(C2O4)2·6H2O, M2+x[PuIV2-xPuIIIx(C2O4)5]·nH2O and M1-x[PuIII1-xPuIVx(C2O4)2·H2O]·nH2O. It is the first time that these well-known compounds are formed by crystal growth methods, thus enabling direct structural studies on transuranic element systems and acquisition of basic data beyond deductions from isomorphic (or not) lanthanide compounds. Characterizations by X-ray diffraction, UV-visible solid spectroscopy, demonstrate the potentialities of these two crystal growth methods to obtain oxalate compounds.

  17. First dedicated hydrographic survey of the Comoros Basin

    NASA Astrophysics Data System (ADS)

    Collins, C.; Hermes, J. C.; Roman, R. E.; Reason, C. J. C.

    2016-02-01

    The Comoros Basin, a region of eddies that propagate into the Mozambique Channel and subsequently the Agulhas Current, has not been well studied. This paper presents the findings from the first dedicated research cruise in the basin. ADCP data collected during the cruise show that the circulation in the Comoros Basin is dominated by the strong westward flowing North East Madagascar Current, which bifurcates twice: once upon encountering the Davie Ridge and again upon reaching the East African coast. One of the branches flows southward along the African coastline and appears to continue into the Mozambique Channel while the other branch turns northward to become the East African Coastal Current. The ADCP data also show evidence of a cyclonic eddy along the northwest coast of Madagascar. Water mass analysis indicates that all the major Indian Ocean water masses are present in the Comoros Basin. Surprisingly, North Atlantic Deep Water, a water mass previously assumed to only occur south of ˜16°S in the Mozambique Channel, was found to be present in the basin at depths below 2000 m. Antarctic Intermediate Water is found to enter the basin via two routes; from the west within the North East Madagascar Current and from the south within the northward flowing Mozambique Undercurrent.

  18. A dedicated compressor monitoring system employing current signature analysis

    SciTech Connect

    Castleberry, K.N.; Smith, S.F.

    1993-04-15

    The use of motor current signature analysis (CSA) has been established as a useful method for periodic monitoring of electrically driven equipment. CSA is, moreover, especially well suited as the basis for a dedicated continuous monitoring system in an industrial setting. This paper presents just such an application that has been developed and installed in the US government uranium enrichment plant at Portsmouth, Ohio. The system, which is designed to detect specific axial-flow compressor problems in 1700-hp gaseous diffusion compressors, is described in detail along with an explanation of detected fault conditions and the required signal manipulations. Amplitude demodulation and subsequent digital processing of motor signals sensed from area control room ammeter loops are used to accomplish the desired monitoring task. Using modified off-the-shelf multiplexing equipment, a 386-type personal computer, and special digital signal processing hardware, the system is presently configured to monitor ten compressors but is expandable to monitor more than 100. Within its first few days of operation in September 1992, the system detected a compressor problem that, when corrected, resulted in a cost avoidance of about $150,000, which more than paid for the hardware and software development costs. Finally, plans to expand system coverage in the coming year are also discussed.

  19. The first dedicated life sciences mission - Spacelab 4

    NASA Astrophysics Data System (ADS)

    Cramer, D. R.; Reid, D. H.; Klein, H. P.

    Spacelab is a large versatile laboratory carried in the bay of the Shuttle Orbiter. The first Spacelab mission dedicated entirely to Life Sciences is known as Spacelab 4. It is scheduled for launch in late 1985 and will remain aloft for seven days. This payload consists of 25 tentatively selected investigations combined into a comprehensive integrated exploration of the effects of acute weightlessness on living systems. An emphasis is placed on studying physiological changes that have been previously observed in manned space flight. This payload has complementary designs in the human and animal investigations in order to validate animal models of human physiology in weightlessness. The experimental subjects include humans, squirrel monkeys, laboratory rats, several species of plants, and frog eggs. The primary scientific objectives include study of the acute cephalic fluid shift, cardiovascular adaptation to weightlessness, including postflight reductions in orthostatic tolerance and exercise capacity, and changes in vestibular function, including space motion sickness, associated with weightlessness. Secondary scientific objectives include the study of red cell mass reduction, negative nitrogen balance, altered calcium metabolism, suppressed in vitro lymphocyte reactivity, gravitropism and photropism in plants, and fertilization and early development in frog eggs. The rationale behind this payload, the selection process, and details of the individual investigations are presented in this paper.

  20. The first dedicated life sciences mission - Spacelab 4

    NASA Technical Reports Server (NTRS)

    Cramer, D. R.; Reid, D. H.; Klein, H. P.

    1983-01-01

    The details of the payload and the experiments in Spacelab 4, the first Spacelab mission dedicated entirely to the life sciences, are discussed. The payload of Spacelab 4, carried in the bay of the Shuttle Orbiter, consists of 25 tentatively selected investigations combined into a comprehensive integrated exploration of the effects of acute weightlessness on living systems. The payload contains complementary designs in the human and animal investigations in order to validate animal models of human physiology in weightlessness. Animals used as experimental subjects will include squirrel monkeys, laboratory rats, several species of plants, and frog eggs. The main scientific objectives of the investigations include the study of the acute cephalic fluid shift, cardiovascular adaptation to weightlessness, including postflight reductions in orthostatic tolerance and exercise capacity, and changes in vestibular function, including space motion sickness, associated with weightlessness. Other scientific objective include the study of red cell mass reduction, negative nitrogen balance, altered calcium metabolism, suppressed in vitro lymphocyte reactivity, gravitropism and photropism in plants, and fertilization and early development in frog eggs.

  1. Electrochemical promotion of propane oxidation on Pt deposited on a dense β″-Al2O3 ceramic Ag+ conductor

    PubMed Central

    Tsampas, Mihalis N.; Kambolis, Anastasios; Obeid, Emil; Lizarraga, Leonardo; Sapountzi, Foteini M.; Vernoux, Philippe

    2013-01-01

    A new kind of electrochemical catalyst based on a Pt porous catalyst film deposited on a β″-Al2O3 ceramic Ag+ conductor was developed and evaluated during propane oxidation. It was observed that, upon anodic polarization, the rate of propane combustion was significantly electropromoted up to 400%. Moreover, for the first time, exponential increase of the catalytic rate was evidenced during galvanostatic transient experiment in excellent agreement with EPOC equation. PMID:24790942

  2. Propane tank explosion (2 deaths, 7 injuries) at Herrig Brothers Feather Creek Farm, Albert City, Iowa, April 9, 1998. Investigation report

    SciTech Connect

    1999-09-01

    This report explains the explosion/BLEVE that took place on April 9, 1998, at the Herrig Brothers Feather Creek Farm, located in Albert City, Iowa. Two volunteer fire fighters were killed and seven other emergency response personnel were injured. Safety issues covered in the report include protection of propane storage tanks and piping, state regulatory oversight of such installations, and fire fighter response to propane storage tank fires.

  3. Enhancing aerobic biodegradation of 1,2-dibromoethane in groundwater using ethane or propane and inorganic nutrients

    NASA Astrophysics Data System (ADS)

    Hatzinger, Paul B.; Streger, Sheryl H.; Begley, James F.

    2015-01-01

    1,2-Dibromoethane (ethylene dibromide; EDB) is a probable human carcinogen that was previously used as both a soil fumigant and a scavenger in leaded gasoline. EDB has been observed to persist in soils and groundwater, particularly under oxic conditions. The objective of this study was to evaluate options to enhance the aerobic degradation of EDB in groundwater, with a particular focus on possible in situ remediation strategies. Propane gas and ethane gas were observed to significantly stimulate the biodegradation of EDB in microcosms constructed with aquifer solids and groundwater from the FS-12 EDB plume at Joint Base Cape Cod (Cape Cod, MA), but only after inorganic nutrients were added. Ethene gas was also effective, but rates were appreciably slower than for ethane and propane. EDB was reduced to < 0.02 μg/L, the Massachusetts state Maximum Contaminant Level (MCL), in microcosms that received ethane gas and inorganic nutrients. An enrichment culture (BE-3R) that grew on ethane or propane gas but not EDB was obtained from the site materials. The degradation of EDB by this culture was inhibited by acetylene gas, suggesting that degradation is catalyzed by a monooxygenase enzyme. The BE-3R culture was also observed to biodegrade 1,2-dichloroethane (DCA), a compound commonly used in conjunction with EDB as a lead scavenger in gasoline. The data suggest that addition of ethane or propane gas with inorganic nutrients may be a viable option to enhance degradation of EDB in groundwater aquifers to below current state or federal MCL values.

  4. The SPASIBA force field of aldehydes. Part I: Structure and vibrational wavenumbers of methanal, ethanal and propanal

    NASA Astrophysics Data System (ADS)

    Zanoun, A.; Durier, V.; Belaidi, A.; Vergoten, G.

    1999-02-01

    The SPASIBA vibrational spectroscopic force field has been developed for the aldehyde function. The tested molecules are methanal, ethanal, propanal and some of their deuterated analogues. The parameters have been obtained by fitting calculated and observed vibrational wavenumbers. A set of 34 independant force constants has been found to correctly describe the structure and vibrational spectra. The average error between predicted and observed vibrational wavenumber is 16 cm -1.

  5. Propane dehydrogenation catalyzed by ZSM-5 zeolites. A mechanistic study based on the selective energy transfer (SET) theory.

    PubMed

    Larsson, Ragnar

    2015-02-02

    Experimentally determined activation energies of propane dehydrogenation catalyzed by ZSM-5 zeolites have been used to test the SET theory. The basis of this theory is that the catalyst system transfers vibrational energy via a resonance process to a specific vibration mode of the reacting molecule. Being excited up to a certain number of vibrational quanta the molecule is brought to reaction. By analyzing the above-mentioned activation energies we found the wave number of this "specific mode" to be 1065 cm-1. This is very close to the rocking vibration of propane (1053 cm-1). We suggest that the propane molecule reacts when excited so that the CH3 group has been forced towards a flat structure with a carbon atom hybridization that is more sp2 than sp3. Consequently there is no way for three H-atoms to bind to the carbon and one of them must leave. This is the starting point of the reaction. The isokinetic temperature of the system was found as Tiso = 727 ± 4 K. From the SET formula for Tiso when both energy-donating (ω) and energy-accepting (ν) vibrations have the same frequency, viz., Tiso = Nhcν/2R, we obtain ν = ω = 1011 ± 6 cm-1. This agrees rather well with the CH3 rocking mode (1053 cm-1) and also with asymmetric "TO4" stretching vibrations of the zeolite structure (ω).

  6. Analysis of high resolution laboratory propane spectra (nu21, 922 cm-1) and the interpretation of Titan's infrared spectra

    NASA Astrophysics Data System (ADS)

    Klavans, Valerie; Nixon, Conor; Hewagama, Tilak; Jennings, Donald

    2010-04-01

    Titan has an extremely thick atmosphere dominated by nitrogen, but includes a range of trace species such as hydrocarbons and nitriles. One such hydrocarbon is propane (C3H8). Propane has 21 active IR bands covering broad regions of the mid-infrared. Therefore, its ubiquitous signature may potentially mask weaker signatures of other undetected species with important roles in Titan's chemistry. Cassini's Composite Infrared Spectrometer (CIRS) observations of Titan's atmosphere hint at the presence of such molecules. Unfortunately, C3H8 line atlases for the vibration bands nu8, nu21, nu20, and nu7 (869, 922, 1054, and 1157 cm-1, respectively) are not currently available for subtracting the C3H8 signal to reveal, or constrain, the signature of underlying chemical species. Using FTS spectra previously obtained by Jennings et al. (unpublished) as the source and automated analysis utilities developed for this application, we are compiling an atlas of spectroscopic parameters for propane that characterize the roto-vibrational transitions in the above bands. In this paper, we will discuss our efforts for the spectral region near the nu21 band, present initial results for spectroscopic parameters including absolute line intensities and transition frequencies, and show how these optical constants will be used in searching for other trace chemical species in Titan's atmosphere.

  7. Temperature-dependent microwave dielectric relaxation studies of hydrogen bonded polar binary mixtures of propan-1-ol and propionaldehyde.

    PubMed

    Vishwam, T; Parvateesam, K; Sreeharisastry, S; Murthy, V R K

    2013-10-01

    The molecular interaction between the polar systems of propan-1-ol and propionaldehyde for various mole fractions at different temperatures were studied by determining the frequency dependent complex dielectric permittivity by using the open-ended coaxial probe technique method in the microwave frequency range from 20 MHz to 20 GHz. The geometries are optimized at HF, B3LYP and MP2 with 6-311G and 6-311G+ basis sets. Dipole moments of the binary mixtures are calculated from the dielectric data using Higasi's method and compared with the theoretical results. Conformational analysis of the formation of hydrogen bond between the propan-1-ol and propionaldehyde is supported by the FT-IR and molecular polarizability calculations. The average relaxation times are calculated from their respective Cole-Cole plots. The activation entropy, activation enthalpy and Kirkwood correlation 'g' factor, excess permittivity (ε(E)), excess inverse relaxation time (1/τ)(E), Bruggeman parameter (f(B)) have also been determined for propan-1-ol and propionaldehyde and the results were correlated.

  8. Temperature-dependent microwave dielectric relaxation studies of hydrogen bonded polar binary mixtures of propan-1-ol and propionaldehyde

    NASA Astrophysics Data System (ADS)

    Vishwam, T.; Parvateesam, K.; SreehariSastry, S.; Murthy, V. R. K.

    2013-10-01

    The molecular interaction between the polar systems of propan-1-ol and propionaldehyde for various mole fractions at different temperatures were studied by determining the frequency dependent complex dielectric permittivity by using the open-ended coaxial probe technique method in the microwave frequency range from 20 MHz to 20 GHz. The geometries are optimized at HF, B3LYP and MP2 with 6-311G and 6-311G+ basis sets. Dipole moments of the binary mixtures are calculated from the dielectric data using Higasi's method and compared with the theoretical results. Conformational analysis of the formation of hydrogen bond between the propan-1-ol and propionaldehyde is supported by the FT-IR and molecular polarizability calculations. The average relaxation times are calculated from their respective Cole-Cole plots. The activation entropy, activation enthalpy and Kirkwood correlation 'g' factor, excess permittivity (ɛE), excess inverse relaxation time (1/τ)E, Bruggeman parameter (fB) have also been determined for propan-1-ol and propionaldehyde and the results were correlated.

  9. Cummins Engine Company B5.9 Propane Engine Development, Certification, and Demonstration Project

    SciTech Connect

    The ADEPT Group, Inc.

    1998-12-18

    The objective of this project was to successfuly develop and certify an LPG-dedicated medium-duty original equipment manufacturer (OEM) engine that could be put into production. The engine was launched into production in 1994, and more than 800 B5.9G engines are now in service in the United States and abroad. This engine is now offered by more than 30 bus and truck OEMs.

  10. Catalytic propane dehydrogenation over In₂O₃–Ga₂O₃ mixed oxides

    SciTech Connect

    Tan, Shuai; Gil, Laura Briones; Subramanian, Nachal; Sholl, David S.; Nair, Sankar; Jones, Christopher W.; Moore, Jason S.; Liu, Yujun; Dixit, Ravindra S.; Pendergast, John G.

    2015-08-26

    We have investigated the catalytic performance of novel In₂O₃–Ga₂O₃ mixed oxides synthesized by the alcoholic-coprecipitation method for propane dehydrogenation (PDH). Reactivity measurements reveal that the activities of In₂O₃–Ga₂O₃ catalysts are 1–3-fold (on an active metal basis) and 12–28-fold (on a surface area basis) higher than an In₂O₃–Al₂O₃ catalyst in terms of C₃H₈ conversion. The structure, composition, and surface properties of the In₂O₃–Ga₂O₃ catalysts are thoroughly characterized. NH₃-TPD shows that the binary oxide system generates more acid sites than the corresponding single-component catalysts. Raman spectroscopy suggests that catalysts that produce coke of a more graphitic nature suppress cracking reactions, leading to higher C₃H₆ selectivity. Lower reaction temperature also leads to higher C₃H₆ selectivity by slowing down the rate of side reactions. XRD, XPS, and XANES measurements, strongly suggest that metallic indium and In₂O₃ clusters are formed on the catalyst surface during the reaction. The agglomeration of In₂O₃ domains and formation of a metallic indium phase are found to be irreversible under O₂ or H₂ treatment conditions used here, and may be responsible for loss of activity with increasing time on stream.

  11. Comparative study on hydrogenation of propanal on Ni(111) and Cu(111) from density functional theory

    NASA Astrophysics Data System (ADS)

    An, Wei; Men, Yong; Wang, Jinguo

    2017-02-01

    Using propanal as a probe molecule, we have comparatively investigated hydrogenation of carbonyl (Cdbnd O) in short carbon-chain aldehyde on Ni(111) and Cu(111) by means of periodic density functional theory. Our focus is in particular on the differentiation of reaction route in sequential hydrogenation on Ni(111) and Cu(111) following Langmuir-Hinshelwood mechanism. Strong binding with alkoxy intermediates has great impact on altering reaction pathways on the two surfaces, where hydroxyl route via 1-hydroxyl propyl intermediate is dominant on Ni(111), but alkoxy route via propoxyl intermediate is more likely on Cu(111) due to a higher activiation barrier of initial hydrogenation in hydroxyl route. In comparison, hydrogenation of carbonyl on Ni(111) is kinetically much faster than that on Cu(111) as a result of much lower activation barrier in rate-determining step (i.e., 13.2 vs 26.8 kcal/mol) of most favorable reaction pathways. Furthermore, the discrepancy in calculated and experimental barriers can be well explained by using the concept of H-tunneling effect on bond forming with H atoms during sequential hydrogenation. The different features of electronic structure exhibited by the two metal surfaces provide insight into their catalytic behaviors.

  12. Kinetic mechanism of plasma recombination in methane, ethane and propane after high-voltage nanosecond discharge

    NASA Astrophysics Data System (ADS)

    Anokhin, E. M.; Popov, M. A.; Kochetov, I. V.; Starikovskiy, A. Yu; Aleksandrov, N. L.

    2016-08-01

    The results of the experimental and numerical study of high-voltage nanosecond discharge afterglow in pure methane, ethane and propane are presented for room temperature and pressures from 2 to 20 Torr. Time-resolved electron density during the plasma decay was measured with a microwave interferometer for initial electron densities in the range between 5  ×  1010 and 3  ×  1012 cm-3 and the effective recombination coefficients were obtained. Measured effective recombination coefficients increased with gas pressure and were much higher than the recombination coefficients for simple molecular hydrocarbon ions. The properties of plasma in the discharge afterglow were numerically simulated by solving the balance equations for charged particles and electron temperature. Calculations showed that electrons had time to thermalize prior to the recombination. The measured data were interpreted under the assumption that cluster hydrocarbon ions are formed during the plasma decay that is controlled by the dissociative electron recombination with these ions at electron room temperature. Based on the analysis of the experimental data, the rates of three-body formation of cluster ions and recombination coefficients for these ions were estimated.

  13. Temperature and pressure influence on explosion pressures of closed vessel propane-air deflagrations.

    PubMed

    Razus, Domnina; Brinzea, Venera; Mitu, Maria; Oancea, Dumitru

    2010-02-15

    An experimental study on pressure evolution during closed vessel explosions of propane-air mixtures was performed, for systems with various initial concentrations and pressures ([C(3)H(8)]=2.50-6.20 vol.%, p(0)=0.3-1.2 bar). The explosion pressures and explosion times were measured in a spherical vessel (Phi=10 cm), at various initial temperatures (T(0)=298-423 K) and in a cylindrical vessel (Phi=10 cm; h=15 cm), at ambient initial temperature. The experimental values of explosion pressures are examined against literature values and compared to adiabatic explosion pressures, computed by assuming chemical equilibrium within the flame front. The influence of initial pressure, initial temperature and fuel concentration on explosion pressures and explosion times are discussed. At constant temperature and fuel/oxygen ratio, the explosion pressures are linear functions of total initial pressure, as reported for other fuel-air mixtures. At constant initial pressure and composition, both the measured and calculated (adiabatic) explosion pressures are linear functions of reciprocal value of initial temperature. Such correlations are extremely useful for predicting the explosion pressures of flammable mixtures at elevated temperatures and/or pressures, when direct measurements are not available.

  14. Cell Transfection with a β-Cyclodextrin-PEI-Propane-1,2,3-Triol Nanopolymer

    PubMed Central

    Lai, Wing-Fu; Jung, Han-Sung

    2014-01-01

    Successful gene therapy necessitates safe and efficient gene transfer. This article describes the use of a cationic polymer, which was synthesized by cross-linking low molecular weight branched poly(ethylenimine) (PEI) with both β-cyclodextrin and propane-1,2,3-triol, for efficient and safe non-viral gene delivery. Experimentation demonstrated that the polymer had a pH buffering capacity and DNA condensing ability comparable to those of PEI 25 kDa. In B16-F0 cells, the polymer increased the transfection efficiency of naked DNA by 700-fold and yielded better transfection efficiencies than Fugene HD (threefold higher) and PEI 25 kDa (fivefold higher). The high transfection efficiency of the polymer was not affected by the presence of serum during transfection. In addition to B16-F0 cells, the polymer enabled efficient transfection of HepG2 and U87 cells with low cytotoxicity. Our results indicated that our polymer is a safe and efficient transfection reagent that warrants further development for in vitro, in vivo and clinical applications. PMID:24956480

  15. Preparation and characterization of foxtail millet bran oil using subcritical propane and supercritical carbon dioxide extraction.

    PubMed

    Shi, Yuzhong; Ma, Yuxiang; Zhang, Ruitin; Ma, Hanjun; Liu, Benguo

    2015-05-01

    The foxtail millet (Setaria italica Beauv) bran oil was extracted with traditional solvent extraction (SE), supercritical carbon dioxide extraction (SCE) and subcritical propane extraction (SPE) and analyzed the yield, physicochemical property, fatty acid profile, tocopherol composition, oil oxidative stability in this study. The yields of foxtail millet bran oil by SE, SCE and SPE were 17.14 %, 19.65 %, 21.79 % of raw material weight (corresponded to 75.54 %, 86.60 %, 96.03 % of the total amount of the oil measured by using Soxhlet extraction), respectively. The effect of the extraction methods on the physicochemical properties (peroxide value, saponification value and color) was significant while the difference in fatty acid profile was negligible based on GC analysis. The major components of vitamin E in the obtained oils were identified as α- and β-tocopherols by HPLC, and SPE was superior to SE and SCE in the extraction of tocopherols. In Rancimat test, the oil obtained by SPE showed the highest oil oxidative stability, which could attribute to its high tocopherol content and low peroxide value. In view of oil quality, SPE employed smaller times and lower pressures compared to SE and SCE. SPE was a suitable and selective method for the extraction of the foxtail millet bran oil.

  16. Synthesis, characterization, antibacterial activity and quantum chemical studies of N'-Acetyl propane sulfonic acid hydrazide

    NASA Astrophysics Data System (ADS)

    Alyar, Saliha; Alyar, Hamit; Ozdemir, Ummuhan Ozmen; Sahin, Omer; Kaya, Kerem; Ozbek, Neslihan; Gunduzalp, Ayla Balaban

    2015-08-01

    A new N'-Acetyl propane sulfonic acid hydrazide, C3H7sbnd SO2sbnd NHsbnd NHsbnd COCH3 (Apsh, an sulfon amide compound) has been synthesized for the first time. The structure of Apsh was investigated using elemental analysis, spectral (IR, 1H/13C NMR) measurements. In addition, molecular structure of the Apsh was determined by single crystal X-ray diffraction technique and found that the compound crystallizes in monoclinic, space group P 21/c. 1H and 13C shielding tensors for crystal structure were calculated with GIAO/DFT/B3LYP/6-311++G(d,p) methods in CDCl3. The structure of Apsh is optimized using Density Functional Theory (DFT) method. The vibrational band assignments were performed at B3LYP/6-311++G(d,p) theory level combined with scaled quantum mechanics force field (SQMFF) methodology. The theoretical IR frequencies are found to be in good agreement with the experimental IR frequencies. Nonlinear optical (NLO) behaviour of Apsh is also examined by the theoretically predicted values of dipole moment (μ), polarizability (α0) and first hyperpolarizability (βtot). The antibacterial activities of synthesized compound were studied against Gram positive bacteria: Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 23212, Staphylococcus epidermidis ATCC 34384, Gram negative bacteria: Eschericha coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 70063 by using microdilution method (as MICs) and disc diffusion method.

  17. Reactivity of alkanes on zeolites: a computational study of propane conversion reactions.

    PubMed

    Zheng, Xiaobo; Blowers, Paul

    2005-12-01

    In this work, quantum chemical methods were used to study propane conversion reactions on zeolites; these reactions included protolytic cracking, primary hydrogen exchange, secondary hydrogen exchange, and dehydrogenation reactions. The reactants, products, and transition-state structures were optimized at the B3LYP/6-31G level and the energies were calculated with CBS-QB3, a complete basis set composite energy method. The computed activation barriers were 62.1 and 62.6 kcal/mol for protolytic cracking through two different transition states, 30.4 kcal/mol for primary hydrogen exchange, 29.8 kcal/mol for secondary hydrogen exchange, and 76.7 kcal/mol for dehydrogenation reactions. The effects of basis set for the geometry optimization and zeolite acidity on the reaction barriers were also investigated. Adding extra polarization and diffuse functions for the geometry optimization did not affect the activation barriers obtained with the composite energy method. The largest difference in calculated activation barriers is within 1 kcal/mol. Reaction activation barriers do change as zeolite acidity changes, however. Linear relationships were found between activation barriers and zeolite deprotonation energies. Analytical expressions for each reaction were proposed so that accurate activation barriers can be obtained when using different zeolites as catalysts, as long as the deprotonation energies are first acquired.

  18. Autoignited laminar lifted flames of propane in coflow jets with tribrachial edge and mild combustion

    SciTech Connect

    Choi, B.C.; Kim, K.N.; Chung, S.H.

    2009-02-15

    Characteristics of laminar lifted flames have been investigated experimentally by varying the initial temperature of coflow air over 800 K in the non-premixed jets of propane diluted with nitrogen. The result showed that the lifted flame with the initial temperature below 860 K maintained the typical tribrachial structure at the leading edge, which was stabilized by the balance mechanism between the propagation speed of tribrachial flame and the local flow velocity. For the temperature above 860 K, the flame was autoignited without having any external ignition source. The autoignited lifted flames were categorized in two regimes. In the case with tribrachial edge structure, the liftoff height increased nonlinearly with jet velocity. Especially, for the critical condition near blowout, the lifted flame showed a repetitive behavior of extinction and reignition. In such a case, the autoignition was controlled by the non-adiabatic ignition delay time considering heat loss such that the autoignition height was correlated with the square of the adiabatic ignition delay time. In the case with mild combustion regime at excessively diluted conditions, the liftoff height increased linearly with jet velocity and was correlated well with the square of the adiabatic ignition delay time. (author)

  19. Raman spectra of methane, ethylene, ethane, dimethyl ether, formaldehyde and propane for combustion applications

    NASA Astrophysics Data System (ADS)

    Magnotti, G.; KC, U.; Varghese, P. L.; Barlow, R. S.

    2015-09-01

    Spontaneous Raman scattering measurements of temperature and major species concentration in hydrocarbon-air flames require detailed knowledge of the Raman spectra of the hydrocarbons present when fuels more complex than methane are used. Although hydrocarbon spectra have been extensively studied at room temperature, there are no data available at higher temperatures. Quantum mechanical calculations, when available are not sufficiently accurate for combustion applications. This work presents experimental measurements of spontaneous Stokes-Raman scattering spectra of methane, ethylene, ethane, dimethyl ether, formaldehyde and propane in the temperature range 300-860 K. Raman spectra from heated hydrocarbons jets have been collected with a higher resolution than is generally employed for Raman measurements in combustion applications. A set of synthetic spectra have been generated for each hydrocarbon, providing the basis for extrapolation to higher temperatures. The spectra provided here will enable simultaneous measurements of multiple hydrocarbons in flames. This capability will greatly extend the range of applicability of Raman measurements in combustion applications. In addition, the experimental spectra provide a validation dataset for quantum mechanical models.

  20. Operation of a Four-Cylinder 1.9L Propane Fueled HCCI Engine

    SciTech Connect

    Flowers, D; Aceves, S M; Martinez-Frias, J; Smith, J R; Au, M; Girard, J; Dibble, R

    2001-03-15

    A four-cylinder 1.9 Volkswagen TDI Engine has been converted to run in Homogeneous Charge Compression Ignition (HCCI) mode. The stock configuration is a turbocharged direct injection Diesel engine. The combustion chamber has been modified by discarding the in-cylinder Diesel fuel injectors and replacing them with blank inserts (which contain pressure transducers). The stock pistons contain a reentrant bowl and have been retained for the tests reported here. The intake and exhaust manifolds have also been retained, but the turbocharger has been removed. A heater has been installed upstream of the intake manifold and fuel is added just downstream of this heater. The performance of this engine in naturally aspirated HCCI operation, subject to variable intake temperature and fuel flow rate, has been studied. The engine has been run with propane fuel at a constant speed of 1800 rpm. This work is intended to characterize the HCCI operation of the engine in this configuration that has been minimally modified from the base Diesel engine. The performance (BMEP, IMEP, efficiency, etc) and emissions (THC, CO, NOx) of the engine are presented, as are combustion process results based on heat release analysis of the pressure traces from each cylinder.

  1. Recreational inhalation of butane and propane in adolescents: Two forensic cases of accidental death.

    PubMed

    Sironi, Luca; Amadasi, Alberto; Zoja, Riccardo

    2016-09-01

    The recreational use of inhalants is a fairly widespread habit among adolescents because of the ease of availability and methods of assumption. Their use is however not free of risks, both for direct toxicity on several target organs and for a mechanism of gas replacement with lack of oxygen. The first case concerns a 12-year-old boy who died suddenly after sniffing a mix of butane and propane contained in a can of air freshener. The second case concerns a 14-year-old boy who died by acute poisoning by the same mixture contained in a refill for lighters. High concentrations of the compounds were found in the tissues by analysis with gas chromatography-mass spectrometry. The compounds found in tissues and biological fluids were perfectly compatible with those contained in the containers used for the inhalation. The mechanisms of death were therefore assessed in a combination of the direct toxicity of the compound and oxygen replacement, thus highlighting the crucial help that toxicological analyses can provide in such cases.

  2. Comparison between a propane-air combustion front and a helium-air simulated combustion front

    SciTech Connect

    Barraclough, S.

    1983-12-01

    Turbulent combustion experiments were performed in a right cylindrical combustion bomb using a premixed propane-air gaseous fuel. The initial conditions inside the combustion chamber were three psig and room temperature. Prior to spark firing, the turbulence intensity inside the combustion chamber was measured and could be varied over a ten fold range. The effect of initial turbulence intensity on turbulent flame propagation was investigated. Two regimes of turbulent combustion were identified, which is in agreement with a previous investigator's results. One of them, a ''transition regime'' occurs when the turbulence intensity is approximately twice the laminar flame speed. Within the transition regime, the turbulent burning speed is linearly proportional to initial turbulence intensity and independent of laminar flame speed and turbulence length scale. A high pressure helium front was injected into the combustion chamber to simulate the combustion front. Since the helium front is isothermal, hot-wire anemometry can be used to quantify the change in turbulence intensity ahead of the propagating front. The helium front was found to have different characteristics than the combustion front.

  3. Cool Flames in Propane-Oxygen Premixtures at Low and Intermediate Temperatures at Reduced-Gravity

    NASA Technical Reports Server (NTRS)

    Pearlman, Howard; Foster, Michael; Karabacak, Devrez

    2003-01-01

    The Cool Flame Experiment aims to address the role of diffusive transport on the structure and the stability of gas-phase, non-isothermal, hydrocarbon oxidation reactions, cool flames and auto-ignition fronts in an unstirred, static reactor. These reactions cannot be studied on Earth where natural convection due to self-heating during the course of slow reaction dominates diffusive transport and produces spatio-temporal variations in the thermal and thus species concentration profiles. On Earth, reactions with associated Rayleigh numbers (Ra) less than the critical Ra for onset of convection (Ra(sub cr) approx. 600) cannot be achieved in laboratory-scale vessels for conditions representative of nearly all low-temperature reactions. In fact, the Ra at 1g ranges from 10(exp 4) - 10(exp 5) (or larger), while at reduced-gravity, these values can be reduced two to six orders of magnitude (below Ra(sub cr)), depending on the reduced-gravity test facility. Currently, laboratory (1g) and NASA s KC-135 reduced-gravity (g) aircraft studies are being conducted in parallel with the development of a detailed chemical kinetic model that includes thermal and species diffusion. Select experiments have also been conducted at partial gravity (Martian, 0.3gearth) aboard the KC-135 aircraft. This paper discusses these preliminary results for propane-oxygen premixtures in the low to intermediate temperature range (310- 350 C) at reduced-gravity.

  4. Chromium and Ruthenium-Doped Zinc Oxide Thin Films for Propane Sensing Applications

    PubMed Central

    Gómez-Pozos, Heberto; González-Vidal, José Luis; Torres, Gonzalo Alberto; Rodríguez-Baez, Jorge; Maldonado, Arturo; de la Luz Olvera, María; Acosta, Dwight Roberto; Avendaño-Alejo, Maximino; Castañeda, Luis

    2013-01-01

    Chromium and ruthenium-doped zinc oxide (ZnO:Cr) and (ZnO:Ru) thin solid films were deposited on soda-lime glass substrates by the sol-gel dip-coating method. A 0.6 M solution of zinc acetate dihydrate dissolved in 2-methoxyethanol and monoethanolamine was used as basic solution. Chromium (III) acetylacetonate and Ruthenium (III) trichloride were used as doping sources. The Ru incorporation and its distribution profile into the films were proved by the SIMS technique. The morphology and structure of the films were studied by SEM microscopy and X-ray diffraction measurements, respectively. The SEM images show porous surfaces covered by small grains with different grain size, depending on the doping element, and the immersions number into the doping solutions. The sensing properties of ZnO:Cr and ZnO:Ru films in a propane (C3H8) atmosphere, as a function of the immersions number in the doping solution, have been studied in the present work. The highest sensitivity values were obtained for films doped from five immersions, 5.8 and 900, for ZnO:Cr and ZnO:Ru films, respectively. In order to evidence the catalytic effect of the chromium (Cr) and ruthenium (Ru), the sensing characteristics of undoped ZnO films are reported as well. PMID:23482091

  5. Effect of Oxygen Enrichment in Propane Laminar Diffusion Flames under Microgravity and Earth Gravity Conditions

    NASA Astrophysics Data System (ADS)

    Bhatia, Pramod; Singh, Ravinder

    2017-01-01

    Diffusion flames are the most common type of flame which we see in our daily life such as candle flame and match-stick flame. Also, they are the most used flames in practical combustion system such as industrial burner (coal fired, gas fired or oil fired), diesel engines, gas turbines, and solid fuel rockets. In the present study, steady-state global chemistry calculations for 24 different flames were performed using an axisymmetric computational fluid dynamics code (UNICORN). Computation involved simulations of inverse and normal diffusion flames of propane in earth and microgravity condition with varying oxidizer compositions (21, 30, 50, 100 % O2, by mole, in N2). 2 cases were compared with the experimental result for validating the computational model. These flames were stabilized on a 5.5 mm diameter burner with 10 mm of burner length. The effect of oxygen enrichment and variation in gravity (earth gravity and microgravity) on shape and size of diffusion flames, flame temperature, flame velocity have been studied from the computational result obtained. Oxygen enrichment resulted in significant increase in flame temperature for both types of diffusion flames. Also, oxygen enrichment and gravity variation have significant effect on the flame configuration of normal diffusion flames in comparison with inverse diffusion flames. Microgravity normal diffusion flames are spherical in shape and much wider in comparison to earth gravity normal diffusion flames. In inverse diffusion flames, microgravity flames were wider than earth gravity flames. However, microgravity inverse flames were not spherical in shape.

  6. Call for a dedicated European legal framework for bacteriophage therapy.

    PubMed

    Verbeken, Gilbert; Pirnay, Jean-Paul; Lavigne, Rob; Jennes, Serge; De Vos, Daniel; Casteels, Minne; Huys, Isabelle

    2014-04-01

    The worldwide emergence of antibiotic resistances and the drying up of the antibiotic pipeline have spurred a search for alternative or complementary antibacterial therapies. Bacteriophages are bacterial viruses that have been used for almost a century to combat bacterial infections, particularly in Poland and the former Soviet Union. The antibiotic crisis has triggered a renewed clinical and agricultural interest in bacteriophages. This, combined with new scientific insights, has pushed bacteriophages to the forefront of the search for new approaches to fighting bacterial infections. But before bacteriophage therapy can be introduced into clinical practice in the European Union, several challenges must be overcome. One of these is the conceptualization and classification of bacteriophage therapy itself and the extent to which it constitutes a human medicinal product regulated under the European Human Code for Medicines (Directive 2001/83/EC). Can therapeutic products containing natural bacteriophages be categorized under the current European regulatory framework, or should this framework be adapted? Various actors in the field have discussed the need for an adapted (or entirely new) regulatory framework for the reintroduction of bacteriophage therapy in Europe. This led to the identification of several characteristics specific to natural bacteriophages that should be taken into consideration by regulators when evaluating bacteriophage therapy. One important consideration is whether bacteriophage therapy development occurs on an industrial scale or a hospital-based, patient-specific scale. More suitable regulatory standards may create opportunities to improve insights into this promising therapeutic approach. In light of this, we argue for the creation of a new, dedicated European regulatory framework for bacteriophage therapy.

  7. New insights into low-temperature oxidation of propane from synchrotron photoionization mass spectrometry and multi-scale informatics modeling

    SciTech Connect

    Welz, Oliver; Burke, Michael P.; Antonov, Ivan O.; Goldsmith, C. Franklin; Savee, John David; Osborn, David L.; Taatjes, Craig A.; Klippenstein, Stephen J.; Sheps, Leonid

    2015-04-10

    We studied low-temperature propane oxidation at P = 4 Torr and T = 530, 600, and 670 K by time-resolved multiplexed photoionization mass spectrometry (MPIMS), which probes the reactants, intermediates, and products with isomeric selectivity using tunable synchrotron vacuum UV ionizing radiation. The oxidation is initiated by pulsed laser photolysis of oxalyl chloride, (COCl)2, at 248 nm, which rapidly generates a ~1:1 mixture of 1-propyl (n-propyl) and 2-propyl (i-propyl) radicals via the fast Cl + propane reaction. At all three temperatures, the major stable product species is propene, formed in the propyl + O2 reactions by direct HO2 elimination from both n- and i-propyl peroxy radicals. The experimentally derived propene yields relative to the initial concentration of Cl atoms are (20 ± 4)% at 530 K, (55 ± 11)% at 600 K, and (86 ± 17)% at 670 K at a reaction time of 20 ms. The lower yield of propene at low temperature reflects substantial formation of propyl peroxy radicals, which do not completely decompose on the experimental time scale. In addition, C3H6O isomers methyloxirane, oxetane, acetone, and propanal are detected as minor products. Our measured yields of oxetane and methyloxirane, which are coproducts of OH radicals, suggest a revision of the OH formation pathways in models of low-temperature propane oxidation. The experimental results are modeled and interpreted using a multiscale informatics approach, presented in detail in a separate publication (Burke, M. P.; Goldsmith, C. F.; Klippenstein, S. J.; Welz, O.; Huang H.; Antonov I. O.; Savee J. D.; Osborn D. L.; Zádor, J.; Taatjes, C. A.; Sheps, L. Multiscale Informatics for Low-Temperature Propane Oxidation: Further Complexities in Studies of Complex Reactions. J. Phys. Chem A. 2015, DOI: 10.1021/acs.jpca.5b01003). Additionally, we found that the model predicts the time profiles and yields of the experimentally observed primary products well

  8. New insights into low-temperature oxidation of propane from synchrotron photoionization mass spectrometry and multi-scale informatics modeling

    DOE PAGES

    Welz, Oliver; Burke, Michael P.; Antonov, Ivan O.; ...

    2015-04-10

    We studied low-temperature propane oxidation at P = 4 Torr and T = 530, 600, and 670 K by time-resolved multiplexed photoionization mass spectrometry (MPIMS), which probes the reactants, intermediates, and products with isomeric selectivity using tunable synchrotron vacuum UV ionizing radiation. The oxidation is initiated by pulsed laser photolysis of oxalyl chloride, (COCl)2, at 248 nm, which rapidly generates a ~1:1 mixture of 1-propyl (n-propyl) and 2-propyl (i-propyl) radicals via the fast Cl + propane reaction. At all three temperatures, the major stable product species is propene, formed in the propyl + O2 reactions by direct HO2 elimination frommore » both n- and i-propyl peroxy radicals. The experimentally derived propene yields relative to the initial concentration of Cl atoms are (20 ± 4)% at 530 K, (55 ± 11)% at 600 K, and (86 ± 17)% at 670 K at a reaction time of 20 ms. The lower yield of propene at low temperature reflects substantial formation of propyl peroxy radicals, which do not completely decompose on the experimental time scale. In addition, C3H6O isomers methyloxirane, oxetane, acetone, and propanal are detected as minor products. Our measured yields of oxetane and methyloxirane, which are coproducts of OH radicals, suggest a revision of the OH formation pathways in models of low-temperature propane oxidation. The experimental results are modeled and interpreted using a multiscale informatics approach, presented in detail in a separate publication (Burke, M. P.; Goldsmith, C. F.; Klippenstein, S. J.; Welz, O.; Huang H.; Antonov I. O.; Savee J. D.; Osborn D. L.; Zádor, J.; Taatjes, C. A.; Sheps, L. Multiscale Informatics for Low-Temperature Propane Oxidation: Further Complexities in Studies of Complex Reactions. J. Phys. Chem A. 2015, DOI: 10.1021/acs.jpca.5b01003). Additionally, we found that the model predicts the time profiles and yields of the experimentally observed primary products well, and shows satisfactory agreement for products

  9. Experimentally determined spectral optimization for dedicated breast computed tomography

    SciTech Connect

    Prionas, Nicolas D.; Huang, Shih-Ying; Boone, John M.

    2011-02-15

    Purpose: The current study aimed to experimentally identify the optimal technique factors (x-ray tube potential and added filtration material/thickness) to maximize soft-tissue contrast, microcalcification contrast, and iodine contrast enhancement using cadaveric breast specimens imaged with dedicated breast computed tomography (bCT). Secondarily, the study aimed to evaluate the accuracy of phantom materials as tissue surrogates and to characterize the change in accuracy with varying bCT technique factors. Methods: A cadaveric breast specimen was acquired under appropriate approval and scanned using a prototype bCT scanner. Inserted into the specimen were cylindrical inserts of polyethylene, water, iodine contrast medium (iodixanol, 2.5 mg/ml), and calcium hydroxyapatite (100 mg/ml). Six x-ray tube potentials (50, 60, 70, 80, 90, and 100 kVp) and three different filters (0.2 mm Cu, 1.5 mm Al, and 0.2 mm Sn) were tested. For each set of technique factors, the intensity (linear attenuation coefficient) and noise were measured within six regions of interest (ROIs): Glandular tissue, adipose tissue, polyethylene, water, iodine contrast medium, and calcium hydroxyapatite. Dose-normalized contrast to noise ratio (CNRD) was measured for pairwise comparisons among the six ROIs. Regression models were used to estimate the effect of tube potential and added filtration on intensity, noise, and CNRD. Results: Iodine contrast enhancement was maximized using 60 kVp and 0.2 mm Cu. Microcalcification contrast and soft-tissue contrast were maximized at 60 kVp. The 0.2 mm Cu filter achieved significantly higher CNRD for iodine contrast enhancement than the other two filters (p=0.01), but microcalcification contrast and soft-tissue contrast were similar using the copper and aluminum filters. The average percent difference in linear attenuation coefficient, across all tube potentials, for polyethylene versus adipose tissue was 1.8%, 1.7%, and 1.3% for 0.2 mm Cu, 1.5 mm Al, and 0.2 mm

  10. AURORA BOREALIS: a polar-dedicated European Research Platform

    NASA Astrophysics Data System (ADS)

    Wolff-Boenisch, Bonnie; Egerton, Paul; Thiede, Joern; Roberto, Azzolini; Lembke-Jene, Lester

    2010-05-01

    global climate change. Chances and challenges rest in securing the construction and operation costs that need a dedicated consortium of interested countries and institutions to help tackling the biggest challenges of the next decades.

  11. Flame front surface characteristics in turbulent premixed propane/air combustion

    SciTech Connect

    Guelder, O.L.; Smallwood, G.J.; Wong, R.; Snelling, D.R.; Smith, R.; Deschamps, B.M.; Sautet, J.C.

    2000-03-01

    The characteristics of the flame front surfaces in turbulent premixed propane/air flames were investigated. Flame front images were obtained using laser-induced fluorescence (LIF) of OH and Mie scattering on two Bunsen-type burners of 11.2-mm and 22.4-mm diameters. Nondimensional turbulence intensity, u{prime}/S{sub L}, was varied from 0.9 to 15, and the Reynolds number, based on the integral length scale, varied from 40 to 467. Approximately 100 images were recorded for each experimental condition. Fractal parameters (fractal dimension, inner and outer cutoffs) and corresponding standard deviations were determined by analysis of the flame front images using the caliper technique. The fractal dimensions derived from OH and Mie scattering images are almost identical. However, inner and outer cutoffs from OH images are consistently higher than those obtained from Mie scattering. The self-similar region of the flame front wrinkling is about a decade for all flames studied. In the nondimensional turbulence intensity range from 1 to 15, it was found that the mean fractal dimension is about 2.2 and it does not show any dependence on turbulence intensity. This contradicts the findings of the previous studies that showed that the fractal dimension asymptotically reaches to 2.35--2.37 when the nondimensional turbulence intensity u{prime}/S{sub L} exceeds 3. It is shown that the reason for this discrepancy is the image analysis method used in the previous studies. Examples are given to show the inadequacy of the circle method used in previous studies for extraction of fractal parameters from flame front images. The fractal parameters obtained so far, in this and previous studies, are not capable of correctly predicting the turbulent burning velocity using the available fractal area closure model.

  12. Stability and catalytic performance of vanadia supported on nanostructured titania catalyst in oxidative dehydrogenation of propane

    NASA Astrophysics Data System (ADS)

    Kootenaei, A. H. Shahbazi; Towfighi, J.; Khodadadi, A.; Mortazavi, Y.

    2014-04-01

    Titanate nanotubes with a high specific surface area were synthesized by the simple hydrothermal method and investigated as support for V2O5 catalyst in oxidative dehydrogenation of propane (ODP). The structures of pristine nanotubes as well as the prepared catalysts were investigated by XRD, Raman, FTIR, HRTEM, SEM, EDS, BET, and XPS techniques. The characterization of the as-synthesized nanotubes showed the synthesis of hydrogen titanate nanotube. The incipient wetness impregnation method was utilized to prepare VTNT-x (x = 5, 10, and 15 wt.% vanadia supported on nanotube) together with VTi5 (5 wt.% vanadia supported on Degussa P25). The anatase phase was developed in VTNT-x catalysts upon calcination along with specific surface area loss. Higher vanadia loading resulted in the lowering of support capacity in maintaining vanadia in dispersed state such that eventually crystalline vanadia appeared. The measured catalyst activity demonstrates that in spite of major support surface area loss in VTNT-5 catalyst, the propylene yield is superior in comparison with VTi5 catalyst. The catalyst activity can be correlated with maximum reduction temperature. Deactivation of VTi5 and VTNT-5 as well as VTNT-15 were studied for 3,000 min time-on-stream. It was found that the activity of VTNT-5 catalyst remain unchanged while a decline in catalytic activity observed in VTi5 and VTNT-15 catalysts. The development of rutile was considered as being a major element in the deactivation of the investigated catalysts which is influenced by the presence of vanadium and reaction atmosphere.

  13. Hydronic Heating Coil Versus Propane Furnace, Rehoboth Beach, Delaware (Fact Sheet)

    SciTech Connect

    Not Available

    2014-01-01

    Insight Homes constructed two houses in Rehoboth Beach, Delaware, with identical floor plans and thermal envelopes but different heating and domestic hot water (DHW) systems. Each house is 1,715-ft2 with a single story, three bedrooms, two bathrooms, and the heating, ventilation, and air conditioning (HVAC) systems and ductwork located in conditioned crawlspaces. The standard house, which the builder offers as its standard production house, uses an air source heat pump (ASHP) with supplemental propane furnace heating. The Building America test house uses the same ASHP unit with supplemental heat provided by the DHW heater (a combined DHW and hydronic heating system, where the hydronic heating element is in the air handler). Both houses were occupied during the test period. Results indicate that efficiency of the two heating systems was not significantly different. Three issues dominate these results; lower system design performance resulting from the indoor refrigerant coil selected for the standard house, an incorrectly functioning defrost cycle in the standard house, and the low resolution of the natural gas monitoring equipment. The thermal comfort of both houses fell outside the ASHRAE Standard 55 heating range but was within the ACCA room-to-room temperature range when compared to the thermostat temperature. The monitored DHW draw schedules were input into EnergyPlus to evaluate the efficiency of the tankless hot water heater model using the two monitored profiles and the Building America House Simulation Protocols. The results indicate that the simulation is not significantly impacted by the draw profiles.

  14. Ionization-cluster distributions of alpha-particles in nanometric volumes of propane: measurement and calculation.

    PubMed

    De Nardo, L; Colautti, P; Conte, V; Baek, W Y; Grosswendt, B; Tornielli, G

    2002-12-01

    The probability of the formation of ionization clusters by primary alpha-particles at 5.4 MeV in nanometric volumes of propane was studied experimentally and by Monte Carlo simulation, as a function of the distance between the center line of the particle beam and the center of the target volume. The volumes were of cylindrical shape, 3.7 mm in diameter and height. As the investigations were performed at gas pressures of 300 Pa and 350 Pa, the dimensions of the target volume were equivalent to 20.6 nm or 24.0 nm in a material of density 1.0 g/cm(3). The dependence of ionization-cluster formation on distance was studied up to values equivalent to about 70 nm. To validate the measurements, a Monte Carlo model was developed which allows the experimental arrangement and the interactions of alpha-particles and secondary electrons in the counter gas to be properly simulated. This model is supplemented by a mathematical formulation of cluster size formation in nanometric targets. The main results of our study are (i) that the mean ionization-cluster size in the delta-electron cloud of an alpha-particle track segment, decreases as a function of the distance between the center line of the alpha-particle beam and the center of the sensitive target volume to the power of 2.6, and (ii) that the mean cluster size in critical volumes and the relative variance of mean cluster size due to delta-electrons are invariant at distances greater than about 20 nm. We could imagine that the ionization-cluster formation in nanometric volumes might in future provide the physical basis for a redefinition of radiation quality.

  15. Dedicated Linac for Radioneurosurgery at the National Institute of Neurology and Neurosurgery of Mexico

    NASA Astrophysics Data System (ADS)

    Celis-López, Miguel A.; Lárraga-Gutiérrez, José M.

    2003-09-01

    The objective is to present a description and the main clinical applications of this dedicated Linac for benign and malignant tumors in the central nervous system. The Novalis (BrainLab, Germany) is a 6 MV dedicated linac for a single high dose Radiosurgery (RS) and for fractionated doses in Stereotactic Radiotherapy with a high level of precision at the isocenter.

  16. Information Literacy Courses in Engineering and Science--The Design and Implementation of the DEDICATE Courses.

    ERIC Educational Resources Information Center

    Fjallbrant, Nancy; Levy, Philippa

    The aim of the DEDICATE (Distance Education Information Courses with Access through Networks) project, funded through the European Union, is to develop distance education courses in training for information literacy. The DEDICATE courses are based on the use of the Internet and World Wide Web; communication between participants and tutors and…

  17. Creating a Dedicated Education Unit in Long-Term Care.

    PubMed

    Fox, Jodie R

    2017-01-17

    adults needing long-term care (LTC) may rise in future aging populations, necessitating an increase in the <1% of nurses currently certified in gerontological nursing. An innovative clinical model, the dedicated education unit (DEU), has been used globally with positive results. The purpose of the current review is to explore the DEU and its possible use in LTC settings, and identify if this clinical model increases nursing students' knowledge of the nursing role. Current literature, including a systematic review, is analyzed and rated for quality. Synthesis of findings show the DEU clinical model may increase student interest and knowledge of LTC nursing through collaboration with the practicing LTC nurse. More longitudinal studies are needed to determine the success of the DEU model as a long-term solution to this clinical problem. [Journal of Gerontological Nursing, xx(x), xx-xx.].

  18. Medical Wikis Dedicated to Clinical Practice: A Systematic Review

    PubMed Central

    Llorca, Guy; Letrilliart, Laurent

    2015-01-01

    Background Wikis may give clinician communities the opportunity to build knowledge relevant to their practice. The only previous study reviewing a set of health-related wikis, without specification of purpose or audience, globally showed a poor reliability. Objective Our aim was to review medical wiki websites dedicated to clinical practices. Methods We used Google in ten languages, PubMed, Embase, Lilacs, and Web of Science to identify websites. The review included wiki sites, accessible and operating, having a topic relevant for clinical medicine, targeting physicians or medical students. Wikis were described according to their purposes, platform, management, information framework, contributions, content, and activity. Purposes were classified as “encyclopedic” or “non-encyclopedic”. The information framework quality was assessed based on the Health On the Net (HONcode) principles for collaborative websites, with additional criteria related to users’ transparency and editorial policy. From a sample of five articles per wikis, we assessed the readability using the Flesch test and compared articles according to the wikis’ main purpose. Annual editorial activities were estimated using the Google engine. Results Among 25 wikis included, 11 aimed at building an encyclopedia, five a textbook, three lessons, two oncology protocols, one a single article, and three at reporting clinical cases. Sixteen wikis were specialized with specific themes or disciplines. Fifteen wikis were using MediaWiki software as-is, three were hosted by online wiki farms, and seven were purpose-built. Except for one MediaWiki-based site, only purpose-built platforms managed detailed user disclosures. The owners were ten organizations, six individuals, four private companies, two universities, two scientific societies, and one unknown. Among 21 open communities, 10 required users’ credentials to give editing rights. The median information framework quality score was 6 out of 16

  19. Dosimetric characterization of a dedicated breast computed tomography clinical prototype

    SciTech Connect

    Sechopoulos, Ioannis; Feng, Steve Si Jia; D'Orsi, Carl J.

    2010-08-15

    Purpose: To investigate the glandular dose magnitudes and characteristics resulting from image acquisition using a dedicated breast computed tomography (BCT) clinical prototype imaging system. Methods: The x-ray spectrum and output characteristics of a BCT clinical prototype (Koning Corporation, West Henrietta, NY) were determined using empirical measurements, breast phantoms, and an established spectrum model. The geometry of the BCT system was replicated in a Monte Carlo-based computer simulation using the GEANT4 toolkit and was validated by comparing the simulated results for exposure distribution in a standard 16 cm CT head phantom with those empirically determined using a 10 cm CT pencil ionization chamber and dosimeter. The computer simulation was further validated by replicating the results of a previous BCT dosimetry study. Upon validation, the computer simulation was modified to include breasts of varying sizes and homogeneous compositions spanning those encountered clinically, and the normalized mean glandular dose resulting from BCT was determined. Using the system's measured exposure output determined automatically for breasts of different size and density, the mean glandular dose for these breasts was computed and compared to the glandular dose resulting from mammography. Finally, additional Monte Carlo simulations were performed to study how the glandular dose values vary within the breast tissue during acquisition with both this BCT prototype and a typical craniocaudal (CC) mammographic acquisition. Results: This BCT prototype uses an x-ray spectrum with a first half-value layer of 1.39 mm Al and a mean x-ray energy of 30.3 keV. The normalized mean glandular dose for breasts of varying size and composition during BCT acquisition with this system ranges from 0.278 to 0.582 mGy/mGy air kerma with the reference air kerma measured in air at the center of rotation. Using the measured exposure outputs for the tube currents automatically selected by the

  20. NMR Spin-Lock Induced Crossing (SLIC) dispersion and long-lived spin states of gaseous propane at low magnetic field (0.05T).

    PubMed

    Barskiy, Danila A; Salnikov, Oleg G; Romanov, Alexey S; Feldman, Matthew A; Coffey, Aaron M; Kovtunov, Kirill V; Koptyug, Igor V; Chekmenev, Eduard Y

    2017-03-01

    When parahydrogen reacts with propylene in low magnetic fields (e.g., 0.05T), the reaction product propane develops an overpopulation of pseudo-singlet nuclear spin states. We studied how the Spin-Lock Induced Crossing (SLIC) technique can be used to convert these pseudo-singlet spin states of hyperpolarized gaseous propane into observable magnetization and to detect (1)H NMR signal directly at 0.05T. The theoretical simulation and experimental study of the NMR signal dependence on B1 power (SLIC amplitude) exhibits a well-resolved dispersion, which is induced by the spin-spin couplings in the eight-proton spin system of propane. We also measured the exponential decay time constants (TLLSS or TS) of these pseudo-singlet long-lived spin states (LLSS) by varying the time between hyperpolarized propane production and SLIC detection. We have found that, on average, TS is approximately 3 times longer than the corresponding T1 value under the same conditions in the range of pressures studied (up to 7.6atm). Moreover, TS may exceed 13s at pressures above 7atm in the gas phase. These results are in agreement with the previous reports, and they corroborate a great potential of long-lived hyperpolarized propane as an inhalable gaseous contrast agent for lung imaging and as a molecular tracer to study porous media using low-field NMR and MRI.

  1. ED-XAS Data Reveal In-situ Time-Resolved Adsorbate Coverage on Supported Molybdenum Oxide Catalysts during Propane Dehydrogenation

    NASA Astrophysics Data System (ADS)

    Ramaker, David; Gatewood, Daniel; Beale, Andrew M.; Weckhuysen, Bert M.

    2007-02-01

    Energy-Dispersive X-ray Absorption Spectroscopy (ED-XAS) data combined with UV/Vis, Raman, and mass spectrometry data on alumina- and silica-supported molybdenum oxide catalysts under propane dehydrogenation conditions have been previously reported. A novel Δμ adsorbate isolation technique was applied here to the time-resolved (0.1 min) Mo K-edge ED-XAS data by taking the difference of absorption, μ, at t>1 against the initial time, t=0. Further, full multiple scattering calculations using the FEFF 8.0 code are performed to interpret the Δμ signatures. The resulting difference spectra and interpretation provide real time propane coverage and O depletion at the MoOn surface. The propane coverage is seen to correlate with the propene and/or coke production, with the maximum coke formation occurring when the propane coverage is the largest. Combined, these data give unprecedented insight into the complicated dynamics for propane dehydrogenation.

  2. NMR Spin-Lock Induced Crossing (SLIC) dispersion and long-lived spin states of gaseous propane at low magnetic field (0.05 T)

    NASA Astrophysics Data System (ADS)

    Barskiy, Danila A.; Salnikov, Oleg G.; Romanov, Alexey S.; Feldman, Matthew A.; Coffey, Aaron M.; Kovtunov, Kirill V.; Koptyug, Igor V.; Chekmenev, Eduard Y.

    2017-03-01

    When parahydrogen reacts with propylene in low magnetic fields (e.g., 0.05 T), the reaction product propane develops an overpopulation of pseudo-singlet nuclear spin states. We studied how the Spin-Lock Induced Crossing (SLIC) technique can be used to convert these pseudo-singlet spin states of hyperpolarized gaseous propane into observable magnetization and to detect 1H NMR signal directly at 0.05 T. The theoretical simulation and experimental study of the NMR signal dependence on B1 power (SLIC amplitude) exhibits a well-resolved dispersion, which is induced by the spin-spin couplings in the eight-proton spin system of propane. We also measured the exponential decay time constants (TLLSS or TS) of these pseudo-singlet long-lived spin states (LLSS) by varying the time between hyperpolarized propane production and SLIC detection. We have found that, on average, TS is approximately 3 times longer than the corresponding T1 value under the same conditions in the range of pressures studied (up to 7.6 atm). Moreover, TS may exceed 13 s at pressures above 7 atm in the gas phase. These results are in agreement with the previous reports, and they corroborate a great potential of long-lived hyperpolarized propane as an inhalable gaseous contrast agent for lung imaging and as a molecular tracer to study porous media using low-field NMR and MRI.

  3. Catalytic properties of the VO x /Ce0.46Zr0.54O2 oxide system in the oxidative dehydrogenation of propane

    NASA Astrophysics Data System (ADS)

    Turakulova, A. O.; Kharlanov, A. N.; Levanov, A. V.; Isaikina, O. Ya.; Lunin, V. V.

    2017-01-01

    Ce0.46Zr0.54O2 solid solution prepared using a cellulose template was employed as a carrier for vanadium catalysts of the oxidative dehydrogenation of propane. The properties of VO x /Ce0.46Zr0.54O2 catalyst (5 wt % vanadium) are compared with the properties of the neat support. The carrier and catalyst are studied by means of BET, SEM, DTA, XRD, and Raman spectroscopy. It is shown that the CeVO4 phase responsible for the ODH process is formed upon interaction between vanadate ions and cerium ions on the surface of the solid solution. The catalytic properties of the catalyst and the support are studied in the propane oxidation reaction at temperatures of 450 and 500°C with pulse feeding of the reagent. It is found that the complete oxidation of propane occurs on the support with formation of CO2 and H2O. Three products (propene, CO2, and H2O) form in the presence of the vanadium catalyst. It is suggested that there are two types of catalytic centers on the catalyst's surface. It is concluded that the centers responsible for the complete oxidation of propane are concentrated mainly on the carrier, while the centers responsible for propane ODH are on the CeVO4.

  4. Extraction of chili, black pepper, and ginger with near-critical CO2, propane, and dimethyl ether: analysis of the extracts by quantitative nuclear magnetic resonance.

    PubMed

    Catchpole, Owen J; Grey, John B; Perry, Nigel B; Burgess, Elaine J; Redmond, Wayne A; Porter, Noel G

    2003-08-13

    Ginger, black pepper, and chili powder were extracted using near-critical carbon dioxide, propane, and dimethyl ether on a laboratory scale to determine the overall yield and extraction efficiency for selected pungent components. The temperature dependency of extraction yield and efficiency was also determined for black pepper and chili using propane and dimethyl ether. The pungency of the extracts was determined by using an NMR technique developed for this work. The volatiles contents of ginger and black pepper extracts were also determined. Extraction of all spice types was carried out with acetone to compare overall yields. Subcritical dimethyl ether was as effective at extracting the pungent principles from the spices as supercritical carbon dioxide, although a substantial amount of water was also extracted. Subcritical propane was the least effective solvent. All solvents quantitatively extracted the gingerols from ginger. The yields of capsaicins obtained by supercritical CO(2) and dimethyl ether were similar and approximately double that extracted by propane. The yield of piperines obtained by propane extraction of black pepper was low at approximately 10% of that achieved with dimethyl ether and CO(2), but improved with increasing extraction temperature.

  5. ED-XAS Data Reveal In-situ Time-Resolved Adsorbate Coverage on Supported Molybdenum Oxide Catalysts during Propane Dehydrogenation

    SciTech Connect

    Ramaker, David; Gatewood, Daniel; Beale, Andrew M.; Weckhuysen, Bert M.

    2007-02-02

    Energy-Dispersive X-ray Absorption Spectroscopy (ED-XAS) data combined with UV/Vis, Raman, and mass spectrometry data on alumina- and silica-supported molybdenum oxide catalysts under propane dehydrogenation conditions have been previously reported. A novel {delta}{mu} adsorbate isolation technique was applied here to the time-resolved (0.1 min) Mo K-edge ED-XAS data by taking the difference of absorption, {mu}, at t>1 against the initial time, t=0. Further, full multiple scattering calculations using the FEFF 8.0 code are performed to interpret the {delta}{mu} signatures. The resulting difference spectra and interpretation provide real time propane coverage and O depletion at the MoOn surface. The propane coverage is seen to correlate with the propene and/or coke production, with the maximum coke formation occurring when the propane coverage is the largest. Combined, these data give unprecedented insight into the complicated dynamics for propane dehydrogenation.

  6. Critical evaluation of Jet-A spray combustion using propane chemical kinetics in gas turbine combustion simulated by KIVA-2

    NASA Technical Reports Server (NTRS)

    Nguyen, H. L.; Ying, S.-J.

    1990-01-01

    Jet-A spray combustion has been evaluated in gas turbine combustion with the use of propane chemical kinetics as the first approximation for the chemical reactions. Here, the numerical solutions are obtained by using the KIVA-2 computer code. The KIVA-2 code is the most developed of the available multidimensional combustion computer programs for application of the in-cylinder combustion dynamics of internal combustion engines. The released version of KIVA-2 assumes that 12 chemical species are present; the code uses an Arrhenius kinetic-controlled combustion model governed by a four-step global chemical reaction and six equilibrium reactions. Researchers efforts involve the addition of Jet-A thermophysical properties and the implementation of detailed reaction mechanisms for propane oxidation. Three different detailed reaction mechanism models are considered. The first model consists of 131 reactions and 45 species. This is considered as the full mechanism which is developed through the study of chemical kinetics of propane combustion in an enclosed chamber. The full mechanism is evaluated by comparing calculated ignition delay times with available shock tube data. However, these detailed reactions occupy too much computer memory and CPU time for the computation. Therefore, it only serves as a benchmark case by which to evaluate other simplified models. Two possible simplified models were tested in the existing computer code KIVA-2 for the same conditions as used with the full mechanism. One model is obtained through a sensitivity analysis using LSENS, the general kinetics and sensitivity analysis program code of D. A. Bittker and K. Radhakrishnan. This model consists of 45 chemical reactions and 27 species. The other model is based on the work published by C. K. Westbrook and F. L. Dryer.

  7. Low-temperature superacid catalysis: Reactions of n - butane and propane catalyzed by iron- and manganese-promoted sulfated zirconia

    SciTech Connect

    Tsz-Keung, Cheung; d`Itri, J.L.; Lange, F.C.; Gates, B.C.

    1995-12-31

    The primary goal of this project is to evaluate the potential value of solid superacid catalysts of the sulfated zirconia type for light hydrocarbon conversion. The key experiments catalytic testing of the performance of such catalysts in a flow reactor fed with streams containing, for example, n-butane or propane. Fe- and Mn-promoted sulfated zirconia was used to catalyze the conversion of n-butane at atmospheric pressure, 225-450{degrees}C, and n-butane partial pressures in the range of 0.0025-0.01 atm. At temperatures <225{degrees}C, these reactions were accompanied by cracking; at temperatures >350{degrees}C, cracking and isomerization occurred. Catalyst deactivation, resulting at least in part from coke formation, was rapid. The primary cracking products were methane, ethane, ethylene, and propylene. The observation of these products along with an ethane/ethylene molar ratio of nearly 1 at 450{degrees}C is consistent with cracking occurring, at least in part, by the Haag-Dessau mechanism, whereby the strongly acidic catalyst protonates n-butane to give carbonium ions. The rate of methane formation from n-butane cracking catalyzed by Fe- and Mn-promoted sulfated zirconia at 450{degrees}C was about 3 x 10{sup -8} mol/(g of catalyst {center_dot}s). The observation of butanes, pentanes, and methane as products is consistent with Olah superacid chemistry, whereby propane is first protonated by a very strong acid to form a carbonium ion. The carbonium ion then decomposes into methane and an ethyl cation which undergoes oligocondensation reactions with propane to form higher molecular weight alkanes. The results are consistent with the identification of iron- and manganese-promoted sulfated zirconia as a superacid.

  8. Carbon doped GaN buffer layer using propane for high electron mobility transistor applications: Growth and device results

    SciTech Connect

    Li, X.; Nilsson, D.; Danielsson, Ö.; Pedersen, H.; Janzén, E.; Forsberg, U.; Bergsten, J.; Rorsman, N.

    2015-12-28

    The creation of a semi insulating (SI) buffer layer in AlGaN/GaN High Electron Mobility Transistor (HEMT) devices is crucial for preventing a current path beneath the two-dimensional electron gas (2DEG). In this investigation, we evaluate the use of a gaseous carbon gas precursor, propane, for creating a SI GaN buffer layer in a HEMT structure. The carbon doped profile, using propane gas, is a two stepped profile with a high carbon doping (1.5 × 10{sup 18 }cm{sup −3}) epitaxial layer closest to the substrate and a lower doped layer (3 × 10{sup 16 }cm{sup −3}) closest to the 2DEG channel. Secondary Ion Mass Spectrometry measurement shows a uniform incorporation versus depth, and no memory effect from carbon doping can be seen. The high carbon doping (1.5 × 10{sup 18 }cm{sup −3}) does not influence the surface morphology, and a roughness root-mean-square value of 0.43 nm is obtained from Atomic Force Microscopy. High resolution X-ray diffraction measurements show very sharp peaks and no structural degradation can be seen related to the heavy carbon doped layer. HEMTs are fabricated and show an extremely low drain induced barrier lowering value of 0.1 mV/V, demonstrating an excellent buffer isolation. The carbon doped GaN buffer layer using propane gas is compared to samples using carbon from the trimethylgallium molecule, showing equally low leakage currents, demonstrating the capability of growing highly resistive buffer layers using a gaseous carbon source.

  9. Carbon doped GaN buffer layer using propane for high electron mobility transistor applications: Growth and device results

    NASA Astrophysics Data System (ADS)

    Li, X.; Bergsten, J.; Nilsson, D.; Danielsson, Ö.; Pedersen, H.; Rorsman, N.; Janzén, E.; Forsberg, U.

    2015-12-01

    The creation of a semi insulating (SI) buffer layer in AlGaN/GaN High Electron Mobility Transistor (HEMT) devices is crucial for preventing a current path beneath the two-dimensional electron gas (2DEG). In this investigation, we evaluate the use of a gaseous carbon gas precursor, propane, for creating a SI GaN buffer layer in a HEMT structure. The carbon doped profile, using propane gas, is a two stepped profile with a high carbon doping (1.5 × 1018 cm-3) epitaxial layer closest to the substrate and a lower doped layer (3 × 1016 cm-3) closest to the 2DEG channel. Secondary Ion Mass Spectrometry measurement shows a uniform incorporation versus depth, and no memory effect from carbon doping can be seen. The high carbon doping (1.5 × 1018 cm-3) does not influence the surface morphology, and a roughness root-mean-square value of 0.43 nm is obtained from Atomic Force Microscopy. High resolution X-ray diffraction measurements show very sharp peaks and no structural degradation can be seen related to the heavy carbon doped layer. HEMTs are fabricated and show an extremely low drain induced barrier lowering value of 0.1 mV/V, demonstrating an excellent buffer isolation. The carbon doped GaN buffer layer using propane gas is compared to samples using carbon from the trimethylgallium molecule, showing equally low leakage currents, demonstrating the capability of growing highly resistive buffer layers using a gaseous carbon source.

  10. Crystal structure of 4-cyclo­hexyl-1-(propan-2-yl­idene)thio­semicarbazide

    PubMed Central

    Yamin, Bohari M; Rodis, Monica Lulo; Chee, Dayang N. B. A

    2014-01-01

    In the title compound, C10H19N3S, the cyclo­hexyl group adopts a chair conformation and adopts a position approximately syn to the thione S atom. The CN2S thio­urea moiety makes dihedral angle of 13.13 (10)° with the propan-2-yl­idene­amino group. An intra­molecular N—H⋯N hydrogen bond is noted. In the crystal, inversion dimers linked by pairs of N—H⋯S hydrogen bonds generate R 2 2(8) loops. PMID:25484699

  11. New example of spontaneous resolution among aryl glycerol ethers: 3-(2,6-dichlorophenoxy)propane-1,2-diol

    NASA Astrophysics Data System (ADS)

    Bredikhina, Zemfira A.; Kurenkov, Alexey V.; Zakharychev, Dmitry V.; Krivolapov, Dmitry B.; Bredikhin, Alexander A.

    2016-08-01

    Using a set of simple tests, based on the properties of ideal conglomerate phase diagrams, it has been suggested to the conglomerate-formative nature of 3-(2,6-dichlorophenoxy)-propane-1,2-diol 1. Additional arguments have been drawn during the study of a single crystal X-ray diffraction study of the compound. The crystal packing details have been evaluated and discussed. Racemic 1 have been resolved into individual (S)- and (R)-components by a preferential crystallization procedure.

  12. N,N′-(Propane-1,3-di­yl)bis­(2-amino­benzamide)

    PubMed Central

    Sreedasyam, Jagannatha Swamy; Sunkari, Jyothi; Kundha, Shashank; Gundapaneni, Raghava Rao

    2013-01-01

    The title compound, C17H20N4O2, was prepared by the reaction between 1,3-di­amino­propane and isatoic anhydride in water. The carbonyl O atoms are involved in intra­molecular hydrogen bonding with the amine group and inter­molecular hydrogen bonding with an amide H atom of an adjacent mol­ecule. In the crystal, pairs of N—H⋯O hydrogen bonds link mol­ecules into inversion dimers and further N—H⋯O hydrogen bonds link the dimers into ladder-like chains along the a axis. PMID:23723834

  13. Oxidative dehydrogenation of propane over molybdenum supported on MgO-{gamma}-Al{sub 2}O{sub 3}

    SciTech Connect

    Abello, M.C.; Gomez, M.F.; Cadus, L.E.

    1996-07-01

    Catalysts of Mo supported on MgO-{gamma} Al{sub 2}O{sub 3} were studied in the oxidative dehydrogenation of propane to propene. The catalysts were active and very stable, but the dehydrogenation selectivity was reduced by the formation of carbon oxides. Characterizations by XRD, XPS, Raman spectroscopy, electron paramagnetic resonance, and BET surface measurements were performed. The catalyst preparation method led to large and stable magnesium molybdate particles on the surface. EPR and XPS measurements gave clues about the fact that the active centers for the reaction include Mo{sup 5+} ions. A scheme for the surface architecture is proposed.

  14. Dedication: phys. stat. sol. (a) 202/15

    NASA Astrophysics Data System (ADS)

    Albrecht, Martin

    2005-12-01

    The papers in this issue are dedicated to Professor Horst Paul Strunk on the occasion of his 65th birthday and his retirement from active teaching. This volume honours a scientist who has made a lasting impact on the field in electron microscopic characterisation of growth and relaxation phenomena in epitaxial growth of semiconductors. Born in The Hague, The Netherlands, on 13 June 1940, he studied physics in Stuttgart where he received his degree in Physics in 1968. He joined the group of Prof. Seeger at the Max-Planck-Institut für Metallforschung and defended his Ph.D. on defects in NaCl at Stuttgart University in 1973. He spent one year at Cornell University as a visiting Professor before joining Technische Universität Hamburg-Harburg in 1983. There he created the Zentralbereich Elektronenmikroskopie and was a professor for materials analytics from 1983 till 1989. In 1989 he changed to the University of Erlangen-Nürnberg, where he established the Verbundlabor für hochauflösende Elektronenmikroskopie and directed the Lehrstuhl Mikrocharakterisierung at the Institut für Werkstoffwissenschaften of the same university. He spent two research periods at the Universities of Rennes in France and Campinas in Brazil. Together with his colleague Prof. Jürgen Werner he created the series of conferences on polycrystalline semiconductors POLYSE which he has been supervising together with Jürgen Werner since 1990.The research activities of Horst P. Strunk are focused on microstructure of materials and their relation to macroscopic physical properties. Main topics are dislocations, their formation and interaction mechanisms, strain relaxation as well as fundamental mechanisms of epitaxial growth. The spectrum of materials covers a wide range starting from metals over ionic crystals, e.g. NaCl to elemental and compound semiconductors. From the beginning, the main tool of study has been the transmission electron microscope. However, Horst P. Strunk recognised that a

  15. Synthese de noir de carbone a partir de propane, utilisant un plasma thermique

    NASA Astrophysics Data System (ADS)

    Lavoie, Martin

    Ce projet de maitrise consiste principalement en une etude experimentale de la production de noir de carbone a haute valeur a partir des fractions lourdes du gaz naturel et a l'aide d'une plasma genere par induction electromagnetique. Cette etude comprend les aspects thermodynamiques de la decomposition des hydrocarbures comme le propane et le n-butane, la filtration en continu du noir de carbone et sa caracterisation. L'etude experimentale est realisee en deux phases distinctes: une phase exploratoire et une phase de mise a l'echelle. A l'issue de la phase exploratoire, un parametre se demarque des autres, le mode d'injection du gaz de procede. En effet, la morphologie du noir de carbone est completement differente selon le type d'injection choisi. Une injection radiale donne un noir de carbone en forme de plaquettes ayant une surface specifique elevee alors qu'une injection axiale donne un noir de carbone en forme de spheres ayant une surface specifique plus faible. Le design du systeme pour la phase de mise a l'echelle a tenu compte majoritairement du parametre qu'est l'injection. De plus, la deuxieme phase a permis une instrumentation adequate, une augmentation de la puissance et du debit du gaz de procede et une frequence differente (3 MHz a 400 kHz). Les resultats de la deuxieme phase se sont averes differents du point de vue morphologique. Plusieurs types d'injection ont ete testes et le noir de carbone obtenu contenait tres peu de plaquettes. L'injection joue un role important pour le taux de decomposition et du noir de carbone produit. Un debit de noir de carbone allant jusqu'a 21 grammes par minute a ete obtenu pour une injection radiale. En fait, les injections radiales testees etaient concues pour perturber l'ecoulement laminaire du plasma et ainsi obtenir de meilleurs echanges que l'injection axiale. Par contre, a faible debit, l'injection axiale est favorisee. Certains aspects demeurent encore a etudier et a approfondir. D'abord, l'effet de la

  16. The solubility of ethane, propane, and carbon dioxide in aqueous solutions of sodium cumene sulfonate.

    PubMed

    King, A D

    2004-05-01

    Measurements have been made to determine the solubilities of ethane, C2H6, propane, C3H8, and carbon dioxide, CO2, in aqueous solutions of sodium cumene sulfonate (NaCS) at 25 degrees C. The solubilities measured for each gas satisfy Henry's law at all concentrations of NaCS. The solubilities of C2H6 and C3H8 exhibit quite similar behavior with respect to added NaCS. The solubilities of these two gases are very low in pure water and are found to be nearly independent of NaCS concentration over a concentration range of 0-0.4 mol NaCS/kg H2O. At intermediate concentrations of NaCS, the solubilities of C2H6 and C3H8 exhibit a gradual increase with added NaCS concentrations ranging from 0.4 to 2.0 mol NaCS/kg H2O. At NaCS concentrations greater than 2.0 mol NaCS/kg H2O, the solubilities of these two gases increase with added NaCS in an approximately linear manner, with the solubility of C3H8 increasing more rapidly than that for C2H6 (by a factor of approximately 2.5). CO2 is much more soluble in pure water than the hydrocarbon gases and exhibits markedly different behavior with respect to added NaCS. The solubility of CO2 decreases with added NaCS over a concentration range of 0-0.9 mol NaCS/kg H2O, passes through a minimum at a concentration of approximately 1.0 mol NaCS/kg H2O, and then increases with added NaCS at higher NaCS concentrations in a manner similar to that observed with C2H6 and C3H8. The trends in solubility observed for these three gases dissolved in aqueous solutions of NaCS resemble those found previously with aqueous solutions of ordinary surfactants. The solubility data measured for these three gases can be interpreted surprisingly well in terms of the mass-action model for micellization, in which salting-out effects due to monomer salt ions suppress gas solubility at low NaCS concentrations and gas solubilization by small micelles of NaCS acts to enhance gas solubility at the higher NaCS concentrations.

  17. Synthesis and characterization of microporous inorganic membranes for propylene/propane separation

    NASA Astrophysics Data System (ADS)

    Ma, Xiaoli

    Membrane-based gas separation is promising for efficient propylene/propane (C3H6/C3H8) separation with low energy consumption and minimum environment impact. Two microporous inorganic membrane candidates, MFI-type zeolite membrane and carbon molecular sieve membrane (CMS) have demonstrated excellent thermal and chemical stability. Application of these membranes into C3H6/C3H 8 separation has not been well investigated. This dissertation presents fundamental studies on membrane synthesis, characterization and C3H 6/C3H8 separation properties of MFI zeolite membrane and CMS membrane. MFI zeolite membranes were synthesized on α-alumina supports by secondary growth method. Novel positron annihilation spectroscopy (PAS) techniques were used to non-destructively characterize the pore structure of these membranes. PAS reveals a bimodal pore structure consisting of intracrystalline zeolitic micropores of ~0.6 nm in diameter and irregular intercrystalline micropores of 1.4 to 1.8 nm in size for the membranes. The template-free synthesized membrane exhibited a high permeance but a low selectivity in C3H 6/C3H8 mixture separation. CMS membranes were synthesized by coating/pyrolysis method on mesoporous gamma-alumina support. Such supports allow coating of thin, high-quality polymer films and subsequent CMS membranes with no infiltration into support pores. The CMS membranes show strong molecular sieving effect, offering a high C3H 6/C3H8 mixture selectivity of ~30. Reduction in membrane thickness from 500 nm to 300 nm causes an increase in C3H8 permeance and He/N2 selectivity, but a decrease in the permeance of He, N 2 and C3H6 and C3H6/C 3H8 selectivity. This can be explained by the thickness dependent chain mobility of the polymer film resulting in final carbon membrane of reduced pore size with different effects on transport of gas of different sizes, including possible closure of C3H6-accessible micropores. CMS membranes demonstrate excellent C3H6/C 3H8 separation

  18. Phytochemical profile, antioxidant and antimicrobial activity of extracts obtained from erva-mate (Ilex paraguariensis) fruit using compressed propane and supercritical CO2.

    PubMed

    Fernandes, Ciro E F; Scapinello, Jaqueline; Bohn, Aline; Boligon, Aline A; Athayde, Margareth L; Magro, Jacir Dall; Palliga, Marshall; Oliveira, J Vladimir; Tres, Marcus V

    2017-01-01

    Traditionally, Ilex paraguariensis leaves are consumed in tea form or as typical drinks like mate and terere, while the fruits are discarded processing and has no commercial value. The aim of this work to evaluate phytochemical properties, total phenolic compounds, antioxidant and antimicrobial activity of extracts of Ilex paraguariensis fruits obtained from supercritical CO2 and compressed propane extraction. The extraction with compressed propane yielded 2.72 wt%, whereas with supercritical CO2 1.51 wt% was obtained. The compound extracted in larger amount by the two extraction solvents was caffeine, 163.28 and 54.17 mg/g by supercritical CO2 and pressurized propane, respectively. The antioxidant activity was more pronounced for the supercritical CO2 extract, with no difference found in terms of minimum inhibitory concentration for Staphylococcus aureus for the two extracts and better results observed for Escherichia coli when using supercritical CO2.

  19. Aurel Sandulescu—a life dedicated to nuclear physics

    NASA Astrophysics Data System (ADS)

    Liotta, R. J.

    2013-02-01

    leaders of Romanian physics. It is in recognition of his contribution to physics, especially nuclear physics, as well as his work for Romanian science that this School is organized in his honour, on the occasion of his 80th birthday. I cannot finish this short account without mentioning the person that accompanied Aurel Sandulescu through all his life, his wife of more than fifty years, Violeta. She also was an exceptional person. In her youth she was a very dedicated sporty girl, very athletic, very courageous, very fair and, above all, very generous. These qualities remained with her throughout her life. With deep sorrow I learnt that she passed away three months ago, still youthful and enthusiastic. R J Liotta

  20. Flame Speeds of Methane-Air, Propane-Air, and Ethylene-Air Mixtures at Low Initial Temperatures

    NASA Technical Reports Server (NTRS)

    Dugger, Gordon L; Heimel, Sheldon

    1952-01-01

    Flame speeds were determined for methane-air, propane-air, and ethylene-air mixtures at -73 C and for methane-air mixtures at -132 C. The data extend the curves of maximum flame speed against initial mixture temperature previously established for the range from room temperature to 344 C. Empirical equations for maximum flame speed u(cm/ sec) as a function of initial mixture temperature T(sub O) were determined to be as follows: for methane, for T(sub O) from 141 to 615 K, u = 8 + 0.000160 T(sub O)(exp 2.11); for propane, for T(sub O) from 200 to 616 K, u = 10 + 0.000342 T(sub O)(exp 2.00); for ethylene, for T(sub O) from 200 to 617 K, u = 10 + 0.00259 T(sub O)(exp 1.74). Relative flame speeds at low initial temperatures were predicted within approximately 20 percent by either the thermal theory as presented by Semenov or by the diffusion theory of Tanford and Pease. The same order was found previously for high initial temperatures. The low-temperature data were also found to extend the linear correlations between maximum flame speed and calculated equilibrium active-radical concentrations, which were established by the previously reported high-temperature data.

  1. Synergistic effect of mixing dimethyl ether with methane, ethane, propane, and ethylene fuels on polycyclic aromatic hydrocarbon and soot formation

    SciTech Connect

    Yoon, S.S.; Anh, D.H.; Chung, S.H.

    2008-08-15

    Characteristics of polycyclic aromatic hydrocarbon (PAH) and soot formation in counterflow diffusion flames of methane, ethane, propane, and ethylene fuels mixed with dimethyl ether (DME) have been investigated. Planar laser-induced incandescence and fluorescence techniques were employed to measure relative soot volume fractions and PAH concentrations, respectively. Results showed that even though DME is known to be a clean fuel in terms of soot formation, DME mixture with ethylene fuel increases PAH and soot formation significantly as compared to the pure ethylene case, while the mixture of DME with methane, ethane, and propane decreases PAH and soot formation. Numerical calculations adopting a detailed kinetics showed that DME can be decomposed to produce a relatively large number of methyl radicals in the low-temperature region where PAH forms and grows; thus the mixture of DME with ethylene increases CH{sub 3} radicals significantly in the PAH formation region. Considering that the increase in the concentration of O radicals is minimal in the PAH formation region with DME mixture, the enhancement of PAH and soot formation in the mixture flames of DME and ethylene can be explained based on the role of methyl radicals in PAH and soot formation. Methyl radicals can increase the concentration of propargyls, which could enhance incipient benzene ring formation through the propargyl recombination reaction and subsequent PAH growth. Thus, the result substantiates the importance of methyl radicals in PAH and soot formation, especially in the PAH formation region of diffusion flames. (author)

  2. Densities and vapor-liquid equilibria in binary mixtures formed by propyl methanoate + ethanol, + propan-1-ol, and + butan-1-ol at 160.0 kPa

    SciTech Connect

    Falcon, J.; Ortega, J.; Gonzalez, E.

    1996-07-01

    Densities and excess volumes were determined at 298.15 K for propyl methanoate + ethanol, + propan-1-ol, and + butan-1-ol. The results of those quantities were then correlated to get the concentrations of vapor-liquid equilibrium obtained isobarically at 160 kPa for the same mixtures. Two mixtures show azeotropes: for propyl methanoate (1) + ethanol (2), x{sub 1} = 0.443 at T = 358.7 K; and for propyl methanoate (1) + propan-1-ol (2), x{sub 1} = 0.762 at T = 368.2 K. The mixtures are thermodynamically consistent, and the predictions made using several group-contribution models are satisfactory.

  3. Propane dehydrogenation over PtSnMg/Cr2O3·Al2O3 catalysts: effect of the amount of Mg loading

    NASA Astrophysics Data System (ADS)

    Zhao, Peng; Guan, Yunfei; Wang, Yanmei; Guo, Xianzhi; Zhang, Jingya; Du, Zongjie; Zhang, Shoumin; Xie, Qinxing; Wu, Shihua

    2017-01-01

    A series of PtSnMg/Cr2O3·Al2O3 catalysts with different Mg loading amounts were synthetized by chemical co-deposition method and their propane dehydrogenation catalytic performances were tested. The catalysts were characterized by XRD, BET, TG, XPS. It was found that alkali metal Mg can reduce the surface acidity of carrier, improve the catalytic performance. Propane conversion peaks at Mg loading of 0.6wt.%, increasing Mg loading further than this saw a decline in conversion.

  4. Bioethanol production from dedicated energy crops and residues in Arkansas, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Globally, one of the major technological goals is cost-effective lignocellulosic ethanol production from biomass feedstocks. Lignocellulosic biomass of five dedicated energy crops and two crops residues were tested for bioethanol production using cellulose solvent-based lignocellulose fractionation...

  5. MINERvA: A Dedicated neutrino scattering experiment at NuMI

    SciTech Connect

    McFarland, Kevin S.; /Rochester U.

    2006-05-01

    MINERvA is a dedicated neutrino cross-section experiment planned for the near detector hall of the NuMI neutrino beam at Fermilab. I summarize the detector design and physics capabilities of the experiment.

  6. Secretary Chu and Administrator D'Agostino at the HEUMF Dedication

    ScienceCinema

    Department of Energy Secretary Steven Chu and Administrator D'Agostino

    2016-07-12

    Speeches by Secretary of Energy Chu and NNSA Administrator Tom D'Agostino at the Highly Enriched Uranium Materials Facility dedication ceremony at the Y-12 National Security Complex in Oak Ridge, Tennessee on March 22, 2010.

  7. 76 FR 446 - Supplemental Security Income (SSI) for the Aged, Blind, and Disabled; Dedicated Accounts and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-05

    ... 221 of the Personal Responsibility and Work Opportunity Reconciliation Act of 1996 (PRWORA). These... From the Federal Register Online via the Government Publishing Office SOCIAL SECURITY...; Dedicated Accounts and Installment Payments for Certain Past- Due SSI Benefits AGENCY: Social...

  8. Secretary Chu and Administrator D'Agostino at the HEUMF Dedication

    SciTech Connect

    Department of Energy Secretary Steven Chu and Administrator D'Agostino

    2010-03-24

    Speeches by Secretary of Energy Chu and NNSA Administrator Tom D'Agostino at the Highly Enriched Uranium Materials Facility dedication ceremony at the Y-12 National Security Complex in Oak Ridge, Tennessee on March 22, 2010.

  9. 33 CFR 157.206 - Dedicated Clean Ballast Tanks Operations Manual for U.S. tank vessels: Submission.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Dedicated Clean Ballast Tanks... MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.206 Dedicated Clean Ballast Tanks Operations Manual for U.S. tank...

  10. 33 CFR 157.206 - Dedicated Clean Ballast Tanks Operations Manual for U.S. tank vessels: Submission.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Dedicated Clean Ballast Tanks... MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.206 Dedicated Clean Ballast Tanks Operations Manual for U.S. tank...

  11. 33 CFR 157.206 - Dedicated Clean Ballast Tanks Operations Manual for U.S. tank vessels: Submission.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Dedicated Clean Ballast Tanks... MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.206 Dedicated Clean Ballast Tanks Operations Manual for U.S. tank...

  12. 33 CFR 157.206 - Dedicated Clean Ballast Tanks Operations Manual for U.S. tank vessels: Submission.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Dedicated Clean Ballast Tanks... MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.206 Dedicated Clean Ballast Tanks Operations Manual for U.S. tank...

  13. 33 CFR 157.206 - Dedicated Clean Ballast Tanks Operations Manual for U.S. tank vessels: Submission.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Dedicated Clean Ballast Tanks... MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels General § 157.206 Dedicated Clean Ballast Tanks Operations Manual for U.S. tank...

  14. Evidence for the Usefulness of Task Performance, Job Dedication, and Interpersonal Facilitation as Components of Overall Performance

    DTIC Science & Technology

    1994-08-01

    Rev 2-89) Author: James R. Van Scotter, Major, USAF Title: Evidence for the Usefulness of Task Performance, Job Dedication, and Interpersonal ...task performance, job dedication, interpersonal facilitation, and overall performance had acceptable reliability. Another group of supervisors provided...independent ratings of the task performance, job dedication, interpersonal facilitation, and overall performance of 760 Air Force mechanics in a second

  15. Modeling of Future-Year Emissions Control Scenarios for the Lower Fraser Valley: Impacts of Natural Gas and Propane Vehicle Technologies.

    NASA Astrophysics Data System (ADS)

    Hedley, M.; Jiang, W.; McLaren, R.; Singleton, D. L.

    1998-10-01

    The MC2-CALGRID photochemical modeling system is used to simulate the impact of two fuel substitution scenarios on ozone levels for a future year in the Lower Fraser Valley of British Columbia, Canada. The relative impacts of selected natural gas and propane vehicle technologies are compared for the year 2005. The chosen natural gas technology imposes large reductions in nonmethane hydrocarbon emissions with moderate reductions in nitrogen oxide emissions, while the propane technology greatly lowers nitrogen oxide emissions with only small changes to nonmethane hydrocarbon emissions.The model results showed that replacing the entire light-duty gasoline car and truck fleet with the selected natural gas vehicle technology in the year 2005 in the Canadian portion of the Lower Fraser Valley yielded significant benefits in terms of reducing potential exposures to elevated ozone levels in suburban and rural areas. Sites closer to the urban core were less affected. For the propane fuel substitution, benefits were realized in terms of lowering ozone concentrations and ozone exposures in the rural areas. Within the urban and suburban areas, ozone exposures tended to increase. The exposures to peroxyacetyl nitrate were universally smaller in the alternative fuel scenarios.The nature of an effective control strategy for the Lower Fraser Valley is discussed, and it is suggested that in addition to the propane fuel substitution, moderate controls on the primary NOx sources in conjunction with moderate nonmethane hydrocarbon controls could be the preferred route to lower ozone exposures.

  16. Solubilities of eta-octadecane, phenanthrene, and eta-octadecane/phenanthrene mixtures in supercritical propane at 390 and 420. Kappa. and pressures to 60 bar

    SciTech Connect

    Dimitrelis, D.; Prausnitz, J.M. )

    1989-07-01

    Solubility data were obtained for n-octadecane, phenanthrene, and a nearly equimolar n-octadecane/phenanthrene mixture in supercritical propane. Solubilities were measured in a flow apparatus at 390 and 420 {Kappa} over the pressure range 35-60 bar. The experimental data is correlated using the perturbed-hard-chain equation of state. Agreement between experiment and correlation is good.

  17. Pd-Ag Membrane Coupled to a Two-Zone Fluidized Bed Reactor (TZFBR) for Propane Dehydrogenation on a Pt-Sn/MgAl2O4 Catalyst

    PubMed Central

    Medrano, José-Antonio; Julián, Ignacio; Herguido, Javier; Menéndez, Miguel

    2013-01-01

    Several reactor configurations have been tested for catalytic propane dehydrogenation employing Pt-Sn/MgAl2O4 as a catalyst. Pd-Ag alloy membranes coupled to the multifunctional Two-Zone Fluidized Bed Reactor (TZFBR) provide an improvement in propane conversion by hydrogen removal from the reaction bed through the inorganic membrane in addition to in situ catalyst regeneration. Twofold process intensification is thereby achieved when compared to the use of traditional fluidized bed reactors (FBR), where coke formation and thermodynamic equilibrium represent important process limitations. Experiments were carried out at 500–575 °C and with catalyst mass to molar flow of fed propane ratios between 15.1 and 35.2 g min mmol−1, employing three different reactor configurations: FBR, TZFBR and TZFBR + Membrane (TZFBR + MB). The results in the FBR showed catalyst deactivation, which was faster at high temperatures. In contrast, by employing the TZFBR with the optimum regenerative agent flow (diluted oxygen), the process activity was sustained throughout the time on stream. The TZFBR + MB showed promising results in catalytic propane dehydrogenation, displacing the reaction towards higher propylene production and giving the best results among the different reactor configurations studied. Furthermore, the results obtained in this study were better than those reported on conventional reactors. PMID:24958620

  18. Minimizing critical layer systematic alignment errors during non-dedicated processing

    NASA Astrophysics Data System (ADS)

    Jekauc, Igor; Roberts, William R.

    2004-05-01

    For the 150 nm and smaller half-pitch geometries, many DRAM manufacturers frequently employ dedicated exposure tool strategy for processing of most critical layers. Individual die tolerances of less than 40 nm are not uncommon for such compact geometries and a method is needed to reduce systematic overlay errors. The dedication strategy relies on the premise that a component of the systematic error induced by the inefficiencies in the exposure tool encountered at a specific layer can be diminished by re-exposing subsequent layer(s) on the same tool thus canceling out a large component of this error. In the past this strategy has, in general, resulted in better overall alignment performance, better exposure tool modeling and in decreased residual modeling errors. Increased alignment performance due to dedication does not come without its price. In such a dedicated strategy wafers are committed to process on the same tool at subsequent lithographic layers thus decreasing manufacturing flexibility and in turn affecting cost through increased processing cycle time. Tool down-events and equipment upgrades requiring significant downtime can also have a significant negative impact on running of a factory. This paper presents volume results for the 140 nm and 110 nm half-pitch geometries using 248 nm and 193 nm respective exposure wavelength state-of-art systems that show that dedicated processing still produces superior overlay and device performance results when compared blindly against non-dedicated processing. Results are also shown that at a given time an acceptable match may be found producing near equivalent results for non-dedicated processing. Changes in alignment capability are also observed after major equipment maintenance and component replacement. A point-in-time predictor strategy utilizing residual modeling errors and a set of modified performance specifications is directly compared against measured overlay data after patterning, against within field AFOV

  19. Hold on to your friends: Dedicated chaperones of ribosomal proteins: Dedicated chaperones mediate the safe transfer of ribosomal proteins to their site of pre-ribosome incorporation.

    PubMed

    Pillet, Benjamin; Mitterer, Valentin; Kressler, Dieter; Pertschy, Brigitte

    2017-01-01

    Eukaryotic ribosomes are assembled from their components, the ribosomal RNAs and ribosomal proteins, in a tremendously complex, multi-step process, which primarily takes place in the nuclear compartment. Therefore, most ribosomal proteins have to travel from the cytoplasm to their incorporation site on pre-ribosomes within the nucleus. However, due to their particular characteristics, such as a highly basic amino acid composition and the presence of unstructured extensions, ribosomal proteins are especially prone to aggregation and degradation in their unassembled state, hence specific mechanisms must operate to ensure their safe delivery. Recent studies have uncovered a group of proteins, termed dedicated chaperones, specialized in accompanying and guarding individual ribosomal proteins. In this essay, we review how these dedicated chaperones utilize different folds to interact with their ribosomal protein clients and how they ensure their soluble expression and interconnect their intracellular transport with their efficient assembly into pre-ribosomes.

  20. Crystal structure of 1,3-bis-[(E)-4-meth-oxy-benzyl-idene-amino]-propan-2-ol.

    PubMed

    Rivera, Augusto; Miranda-Carvajal, Ingrid; Ríos-Motta, Jaime; Bolte, Michael

    2016-12-01

    The title Schiff base, C19H22N2O3, was synthesized via the condensation reaction of 1,3-di-amino-propan-2-ol with 4-meth-oxy-benzaldehyde using water as solvent. The mol-ecule exists in an E,E conformation with respect to the C=N imine bonds and the dihedral angle between the aromatic rings is 37.25 (15)°. In the crystal, O-H⋯N hydrogen bonds link the mol-ecules into infinite C(5) chains propagating along the a-axis direction. The packing of these chains is consolidated by C-H⋯O inter-actions and C-H⋯π short contacts, forming a three-dimensional network.

  1. An application of particle image velocimetry to the direct measurement of laminar burning velocity in homogeneous propane-air mixtures

    SciTech Connect

    Zhou, M.; Garner, C.P.

    1995-12-31

    An experiment is described for the direct measurement of laminar burning velocity within an optically accessed cylindrical combustion chamber. The laminar burning velocity was determined directly as the difference between the flame propagation speed and the unburned gas velocity immediately ahead of the flame front. Particle Image Velocimetry (PIV) has been applied to measure the unburned gas velocity field. The local flame speed and flame front position were determined from a pair of ionization probes in conjunction with the simultaneous PIV measurement. The laminar burning velocity of propane-air mixtures initially at atmospheric condition for different equivalence ratios ranging from 0.7--1.4 are presented. Close agreement with other measurements and predicted results was found.

  2. Occurrence of 3-chloro-propane-1,2-diol (3-MCPD) and related compounds in foods: a review.

    PubMed

    Hamlet, C G; Sadd, P A; Crews, C; Velísek, J; Baxter, D E

    2002-07-01

    A critical review of the occurrence of 3-chloro-propane-1,2-diol (3-MCPD) in foods not known to contain hydrolysed vegetable proteins is presented. The review covers the properties and chemistry of 3-MCPD and the current methods of analysis in foodstuffs. The results of UK surveys of 3-MCPD occurrence in both retail foods and commercial food ingredients are discussed with particular reference to cereal, meat and dairy products. The possible mechanisms for the formation and decay of 3-MCPD in foods are suggested. The review does not cover the detailed toxicology of 3-MCPD and its occurrence in hydrolysed vegetable proteins, which have been considered elsewhere, nor possible issues such as in-vivo formation.

  3. Performance and efficiency evaluations of new fluorinated ethers, propanes, and butanes. Report for January-April 1993

    SciTech Connect

    Gage, C.L.; Kazachki, G.S.

    1993-01-01

    The paper gives results of a thermodynamic evaluation that investigates the performance of 15 new chemicals as refrigerants, the impact of the new chemicals on compressor size and operating characteristics, and the efficiency of the refrigerants in vapor compression cycles. Their efficiency in the basic vapor compression cycle is low, but improves substantially in a cycle with internal heat exchange. Several alternatives are identified as promising replacements. As a step in evaluating the potential performance of the 15 compounds, the evaluation using limited property data was performed on the chemicals for use as refrigerants in supermarket, chiller, refrigerator/freezer, heat pump, and air conditioning applications. The 15 chemicals included 10 fluorinated propanes, 3 fluorinated butanes, and 2 fluorinated ethers which are potential chlorofluorocarbon (CFC) and hydrochlorofluorocarbon replacements.

  4. Study of the conditions necessary for propane-jet freezing of fresh biological tissues without detectable ice formation.

    PubMed

    Haggis, G H

    1986-09-01

    The performance of a commercial double-propane-jet freezer (Balzers QFD 101) has been assessed, for rapid freezing of fresh tissues in freeze-etch work. Samples of diaphragm muscle and intestinal villi were frozen between copper sheets, with a spacer to give 20-30 microns thickness of tissue. Fracture cuts were made with the Balzers BAF 400 freeze-etch microtome within 5-10 microns of a freezing face (i.e. a tissue face in contact with the copper sheets of the frozen sandwich). After some modifications to the QFD 101, replicas showing no evidence of ice were obtained of muscle cells, although for intestinal epithelial cells some evidence of ice formation was found. Infiltration with 5% glycerol or dimethylsulphoxide improves the depth of good freezing. Results and problems arising from such infiltration are briefly discussed.

  5. The promising chemical kinetics for the simulation of propane-air combustion with KIVA-II code

    NASA Technical Reports Server (NTRS)

    Ying, S. J.; Gorla, Rama S. R.; Kundu, Krishna P.

    1993-01-01

    The development of chemical kinetics for the simulation of propane-air combustion with the use of computer code KIVA-II since 1989 is summarized here. In order to let readers understand the general feature well, a brief description of the KIVA-II code, specially related with the chemical reactions is also given. Then the results of recent work with 20 reaction mechanism is presented. It is also compared with the 5 reaction mechanism. It may be expected that the numerical stability of the 20 reaction mechanism is better as compared to that of 5 reaction mechanism, but the CPU time of the CRAY computer is much longer. Details are presented in the paper.

  6. Laboratory measurements of cross sections of propane in the 7 - 15 μm using FT-IR at cold temperatures

    NASA Astrophysics Data System (ADS)

    Sung, K.; Toon, G. C.; Brown, L. R.; Mantz, A. W.; Smith, M. A.

    2012-12-01

    Propane (C3H8) is one of the most abundant non-methane hydrocarbons (NMHC) in the natural environment of the Earth. In addition to biogenic and anthropogenic emissions, the natural degassing from geological processes is also reported to be a significant source (Etiope and Ciccioli, Science, 323, 478, 1999). At Titan, propane is an important component of the photochemistry and may provide insights into pre-biotic chemistry. To support atmospheric remote sensing of propane, absorption cross sections of N2-broadened C3H8 were obtained at temperatures between 145 and 296 K at the Jet Propulsion Laboratory. For this, 17 spectra of pure- and N2-broadened propane were recorded in the 690 to 1550 cm-1 region using a Fourier transform spectrometer (Bruker IFS-125HR) configured with a 20.38 cm long temperature-stabilized cryogenic absorption cell, developed at Connecticut College (Mantz, et al., Mol.Spectrosc. Symposium at OSU, 2010; Sung et al. JMS, 262, 122, 2010). We report the absorption cross sections at the various cold temperatures for several strong propane bands in the region. In addition, we present empirical positions, intensities, and lower state energies' determined by fitting "pseudo-lines" to the high-resolution laboratory spectra, (see http://mark4sun.jpl.nasa.gov/data/ spec/Pseudo/Readme). The resulting compilation will be compared to earlier work, including the C3H8+N2 spectra recorded at PNNL (Sharpe, et al. Appl Spectrosc 58, 1452, 2004) and available line-by-line predictions (Flaud et al., J Chem Phys 114, 9361, 2001; Flaud et al. Mol Phys 108, 699, 2010). [ Research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, Connecticut College, and NASA Langley Research Center, under contracts and cooperative agreements with the National Aeronautics and Space Administration.

  7. Biodegradation of the gasoline oxygenates methyl tert-butyl ether, ethyl tert-butyl ether, and tert-amyl methyl ether by propane-oxidizing bacteria.

    PubMed

    Steffan, R J; McClay, K; Vainberg, S; Condee, C W; Zhang, D

    1997-11-01

    Several propane-oxidizing bacteria were tested for their ability to degrade gasoline oxygenates, including methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME). Both a laboratory strain and natural isolates were able to degrade each compound after growth on propane. When propane-grown strain ENV425 was incubated with 20 mg of uniformly labeled [14C]MTBE per liter, the strain converted > 60% of the added MTBE to 14CO2 in < 30 h. The initial oxidation of MTBE and ETBE resulted in the production of nearly stoichiometric amounts of tert-butyl alcohol (TBA), while the initial oxidation of TAME resulted in the production of tert-amyl alcohol. The methoxy methyl group of MTBE was oxidized to formaldehyde and ultimately to CO2. TBA was further oxidized to 2-methyl-2-hydroxy-1-propanol and then 2-hydroxy isobutyric acid; however, neither of these degradation products was an effective growth substrate for the propane oxidizers. Analysis of cell extracts of ENV425 and experiments with enzyme inhibitors implicated a soluble P-450 enzyme in the oxidation of both MTBE and TBA. MTBE was oxidized to TBA by camphor-grown Pseudomonas putida CAM, which produces the well-characterized P-450cam, but not by Rhodococcus rhodochrous 116, which produces two P-450 enzymes. Rates of MTBE degradation by propane-oxidizing strains ranged from 3.9 to 9.2 nmol/min/mg of cell protein at 28 degrees C, whereas TBA was oxidized at a rate of only 1.8 to 2.4 nmol/min/mg of cell protein at the same temperature.

  8. The Application of Dedicated Controllers to Parallel/Serial Exhauster Trains

    NASA Technical Reports Server (NTRS)

    Sadhukhan, Debashis; Dever, Therese M.

    1998-01-01

    Twenty new dedicated controllers were interfaced to the Distributed Control System (DCS) at NASA Lewis Research Center. Better surge avoidance, improved energy savings, interface intricacies, and plant complexities are the subjects of this paper. Problems with the existing Programmable Logic Controller (PLC) control logic are described as well as the solutions implemented with the new controllers. The complexity of the new communication network between the dedicated controllers, Multipurpose Micro-Processor (MMPs), and the operator workstations are illustrated. The complicated nature of the plant and methods of controlling the associated processes are also discussed.

  9. Complex chemical composition of colored surface films formed from reactions of propanal in sulfuric acid at upper troposphere/lower stratosphere aerosol acidities

    NASA Astrophysics Data System (ADS)

    Van Wyngarden, A. L.; Pérez-Montaño, S.; Bui, J. V. H.; Li, E. S. W.; Nelson, T. E.; Ha, K. T.; Leong, L.; Iraci, L. T.

    2015-04-01

    Particles in the upper troposphere and lower stratosphere (UT/LS) consist mostly of concentrated sulfuric acid (40-80 wt%) in water. However, airborne measurements have shown that these particles also contain a significant fraction of organic compounds of unknown chemical composition. Acid-catalyzed reactions of carbonyl species are believed to be responsible for significant transfer of gas phase organic species into tropospheric aerosols and are potentially more important at the high acidities characteristic of UT/LS particles. In this study, experiments combining sulfuric acid (H2SO4) with propanal and with mixtures of propanal with glyoxal and/or methylglyoxal at acidities typical of UT/LS aerosols produced highly colored surface films (and solutions) that may have implications for aerosol properties. In order to identify the chemical processes responsible for the formation of the surface films, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and 1H nuclear magnetic resonance (NMR) spectroscopies were used to analyze the chemical composition of the films. Films formed from propanal were a complex mixture of aldol condensation products, acetals and propanal itself. The major aldol condensation products were the dimer (2-methyl-2-pentenal) and 1,3,5-trimethylbenzene that was formed by cyclization of the linear aldol condensation trimer. Additionally, the strong visible absorption of the films indicates that higher-order aldol condensation products must also be present as minor species. The major acetal species were 2,4,6-triethyl-1,3,5-trioxane and longer-chain linear polyacetals which are likely to separate from the aqueous phase. Films formed on mixtures of propanal with glyoxal and/or methylglyoxal also showed evidence of products of cross-reactions. Since cross-reactions would be more likely than self-reactions under atmospheric conditions, similar reactions of aldehydes like propanal with common aerosol organic species like glyoxal and

  10. Complex chemical composition of colored surface films formed from reactions of propanal in sulfuric acid at upper troposphere/lower stratosphere aerosol acidities

    NASA Astrophysics Data System (ADS)

    Van Wyngarden, A. L.; Pérez-Montaño, S.; Bui, J. V. H.; Li, E. S. W.; Nelson, T. E.; Ha, K. T.; Leong, L.; Iraci, L. T.

    2014-11-01

    Particles in the upper troposphere and lower stratosphere (UT/LS) consist mostly of concentrated sulfuric acid (40-80 wt %) in water. However, airborne measurements have shown that these particles also contain a significant fraction of organic compounds of unknown chemical composition. Acid-catalyzed reactions of carbonyl species are believed to be responsible for significant transfer of gas phase organic species into tropospheric aerosols and are potentially more important at the high acidities characteristic of UT/LS particles. In this study, experiments combining sulfuric acid (H2SO4) with propanal and with mixtures of propanal with glyoxal and/or methylglyoxal at acidities typical of UT/LS aerosols produced highly colored surface films (and solutions) that may have implications for aerosol properties. In order to identify the chemical processes responsible for the formation of the surface films, Attenuated Total Reflectance-Fourier Transform Infrared and 1H Nuclear Magnetic Resonance spectroscopies were used to analyze the chemical composition of the films. Films formed from propanal were a complex mixture of aldol condensation products, acetals and propanal itself. The major aldol condensation products were the dimer (2-methyl-2-pentenal) and 1,3,5-trimethylbenzene, which was formed by cyclization of the linear aldol condensation trimer. Additionally, the strong visible absorption of the films indicates that higher order aldol condensation products must also be present as minor species. The major acetal species were 2,4,6-triethyl-1,3,5-trioxane and longer-chain linear polyacetals which are likely to separate from the aqueous phase. Films formed on mixtures of propanal with glyoxal and/or methylglyoxal also showed evidence for products of cross-reactions. Since cross-reactions would be more likely than self-reactions under atmospheric conditions, similar reactions of aldehydes like propanal with common aerosol organic species like glyoxal and methylglyoxal

  11. Complex chemical composition of colored surface films formed from reactions of propanal in sulfuric acid at upper troposphere/lower stratosphere aerosol acidities

    PubMed Central

    Van Wyngarden, A. L.; Pérez-Montaño, S.; Bui, J. V. H.; Li, E. S. W.; Nelson, T. E.; Ha, K. T.; Leong, L.; Iraci, L. T.

    2016-01-01

    Particles in the upper troposphere and lower stratosphere (UT/LS) consist mostly of concentrated sulfuric acid (40–80 wt %) in water. However, airborne measurements have shown that these particles also contain a significant fraction of organic compounds of unknown chemical composition. Acid-catalyzed reactions of carbonyl species are believed to be responsible for significant transfer of gas phase organic species into tropospheric aerosols and are potentially more important at the high acidities characteristic of UT/LS particles. In this study, experiments combining sulfuric acid (H2SO4) with propanal and with mixtures of propanal with glyoxal and/or methylglyoxal at acidities typical of UT/LS aerosols produced highly colored surface films (and solutions) that may have implications for aerosol properties. In order to identify the chemical processes responsible for the formation of the surface films, attenuated total reflectance–Fourier transform infrared (ATR-FTIR) and 1H nuclear magnetic resonance (NMR) spectroscopies were used to analyze the chemical composition of the films. Films formed from propanal were a complex mixture of aldol condensation products, acetals and propanal itself. The major aldol condensation products were the dimer (2-methyl-2-pentenal) and 1,3,5-trimethylbenzene that was formed by cyclization of the linear aldol condensation trimer. Additionally, the strong visible absorption of the films indicates that higher-order aldol condensation products must also be present as minor species. The major acetal species were 2,4,6-triethyl-1,3,5-trioxane and longer-chain linear polyacetals which are likely to separate from the aqueous phase. Films formed on mixtures of propanal with glyoxal and/or methylglyoxal also showed evidence of products of cross-reactions. Since cross-reactions would be more likely than self-reactions under atmospheric conditions, similar reactions of aldehydes like propanal with common aerosol organic species like glyoxal and

  12. Complex chemical composition of colored surface films formed from reactions of propanal in sulfuric acid at upper troposphere/lower stratosphere aerosol acidities.

    PubMed

    Van Wyngarden, A L; Pérez-Montaño, S; Bui, J V H; Li, E S W; Nelson, T E; Ha, K T; Leong, L; Iraci, L T

    Particles in the upper troposphere and lower stratosphere (UT/LS) consist mostly of concentrated sulfuric acid (40-80 wt %) in water. However, airborne measurements have shown that these particles also contain a significant fraction of organic compounds of unknown chemical composition. Acid-catalyzed reactions of carbonyl species are believed to be responsible for significant transfer of gas phase organic species into tropospheric aerosols and are potentially more important at the high acidities characteristic of UT/LS particles. In this study, experiments combining sulfuric acid (H2SO4) with propanal and with mixtures of propanal with glyoxal and/or methylglyoxal at acidities typical of UT/LS aerosols produced highly colored surface films (and solutions) that may have implications for aerosol properties. In order to identify the chemical processes responsible for the formation of the surface films, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and (1)H nuclear magnetic resonance (NMR) spectroscopies were used to analyze the chemical composition of the films. Films formed from propanal were a complex mixture of aldol condensation products, acetals and propanal itself. The major aldol condensation products were the dimer (2-methyl-2-pentenal) and 1,3,5-trimethylbenzene that was formed by cyclization of the linear aldol condensation trimer. Additionally, the strong visible absorption of the films indicates that higher-order aldol condensation products must also be present as minor species. The major acetal species were 2,4,6-triethyl-1,3,5-trioxane and longer-chain linear polyacetals which are likely to separate from the aqueous phase. Films formed on mixtures of propanal with glyoxal and/or methylglyoxal also showed evidence of products of cross-reactions. Since cross-reactions would be more likely than self-reactions under atmospheric conditions, similar reactions of aldehydes like propanal with common aerosol organic species like glyoxal and

  13. Bridge to the Future: Franklin Roosevelt's Speech at the Dedication of the Triborough Bridge

    ERIC Educational Resources Information Center

    Rosenbaum, David L.

    2009-01-01

    When President Franklin D. Roosevelt took office on March 4, 1933, 15 million Americans, or one quarter of the nation's workers, were jobless. Hope faded as despair spread. Three years later, on July 10, 1936, Roosevelt took a special overnight train from Washington, D.C., to New York City for the dedication of the Triborough Bridge. The next day,…

  14. 33 CFR 157.225 - Dedicated clean ballast tanks operations: General.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., the pump and piping system for conveying the ballast are flushed with water; (c) Before the pump and... dedicated clean ballast tanks is used for flushing the pump and piping system, the volume of water for... content of the flushing water in the piping system is monitored; and (2) The pump and piping system...

  15. 33 CFR 157.225 - Dedicated clean ballast tanks operations: General.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., the pump and piping system for conveying the ballast are flushed with water; (c) Before the pump and... dedicated clean ballast tanks is used for flushing the pump and piping system, the volume of water for... content of the flushing water in the piping system is monitored; and (2) The pump and piping system...

  16. 33 CFR 157.225 - Dedicated clean ballast tanks operations: General.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., the pump and piping system for conveying the ballast are flushed with water; (c) Before the pump and... dedicated clean ballast tanks is used for flushing the pump and piping system, the volume of water for... content of the flushing water in the piping system is monitored; and (2) The pump and piping system...

  17. Manpower Conference for the Health Related Professions, and Dedication, School of Health Related Professions.

    ERIC Educational Resources Information Center

    Perry, J. Warren, Ed.

    More than 400 persons including national leaders in government, educational, and professional organizations and agencies attended the dedication and the 3-day conference intended to focus attention on priority needs. Conference papers include: (1) "Serving Is a Privilege, Not a Problem" by M.E. Switzer, (2) "Regional Medical…

  18. Genetic Modification in Dedicated Bioenergy Crops and Strategies for Gene Confinement

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic modification of dedicated bioenergy crops is in its infancy; however, there are numerous advantages to the use of these tools to improve crops used for biofuels. Potential improved traits through genetic engineering (GE) include herbicide resistance, pest, drought, cold and salt tolerance, l...

  19. Comparison of programmable legend keyboard and dedicated keyboard for control of the flight management computer

    NASA Technical Reports Server (NTRS)

    Crane, Jean M.; Boucek, George P., Jr.; Smith, Wayne D.

    1986-01-01

    A study is described which compares two types of input devices used to operate a flight management computer: a programmable legend (multifunction) keyboard and a conventional (dedicated) keyboard. Pilot performance measures, subjective responses, and a timeline analysis were used in evaluating the two keyboard concepts. A discussion of the factors to be considered in the implementation of a multifunction keyboard is included.

  20. Mrs. Hugh Dryden unveils the memorial to her late husband at center dedication, with center director

    NASA Technical Reports Server (NTRS)

    1976-01-01

    On March 26, 1976, the NASA Flight Research Center opened its doors to hundreds of guests for the dedication of the center in honor of Hugh Latimer Dryden. The dedication was very much a local event; following Center Director David Scott's opening remarks, the Antelope Valley High School's symphonic band played the national anthem. Invocation was given followed by recognition of the invited guests. Dr. Hugh Dryden, a man of total humility, received praise from all those present. Dryden, who died in 1965, had been a pioneering aeronautical scientist who became director of the National Advisory Committee for Aeronautics (NACA) in 1949 and then deputy administrator of the NACA's successor, NASA, in 1958. Very much interested in flight research, he had been responsible for establishing a permanent facility at the location later named in his honor. As Center Director David Scott looks on, Mrs. Hugh L. Dryden (Mary Libbie Travers) unveils the memorial to her husband at the dedication ceremony.On March 26, 1976, the NASA Flight Research Center opened its doors to hundreds of guests for the dedication of the center in honor of Hugh Latimer Dryden.

  1. The Relationships between a Dedicated Education Unit and Quality of Nursing Care

    ERIC Educational Resources Information Center

    Tochterman, Lori A.

    2016-01-01

    The Dedicated Education Unit (DEU) is a model of clinical teaching which has gained widespread acceptance and national recognition as an innovative method of clinical education for undergraduate nursing students (Robert Wood Johnson Foundation, 2010; Warner & Burton, 2009). The primary goals and benefits of the DEU for schools of nursing are…

  2. Role, Impacts and Implications of Dedicated Aboriginal Student Space at a Canadian University

    ERIC Educational Resources Information Center

    Smith, Natasha L.; Varghese, Jeji

    2016-01-01

    This article draws on a case study of the University of Guelph's Aboriginal Resource Centre (ARC) to identify the role that dedicated spaces have in the lives of Aboriginal students. Three roles that were identified include how these spaces build a sense of community, foster and enhance Aboriginal identity, and provide a safe space for Aboriginal…

  3. A Dedicated Postpartum Intrauterine Device Inserter: Pilot Experience and Proof of Concept

    PubMed Central

    Singh, Sharad; Das, Vinita; Agarwal, Anjoo; Dewan, Rupali; Mittal, Pratima; Bhamrah, Renita; Lerma, Klaira; Blumenthal, Paul D

    2016-01-01

    ABSTRACT Objective: To assess the feasibility, acceptability, and safety of a dedicated postpartum intrauterine device (PPIUD) inserter specifically designed for the post-delivery setting. Primary objectives of fundal placement and expulsion rates were assessed. Secondary objectives were participant satisfaction and IUD retention. Methods: In this pilot proof of concept, we enrolled 80 women who presented for PPIUD insertion at 2 government hospitals in Delhi and Lucknow, India, between March and July 2015. PPIUD insertion was completed with the dedicated inserter in all cases, by trained providers with no prior experience in PPIUD insertion, followed immediately by ultrasound to assess location and fundal placement of the IUD. Follow-up took place at 6 to 8 weeks post-insertion, and ultrasound was used to assess IUD location. Providers and participants also completed satisfaction surveys. Results: High fundal placement (≤10 mm from uterine fundus) was achieved with the dedicated PPIUD inserter in 82% of cases (n = 65). There were no perforations or infections among the participants and no other complications associated with use of the dedicated inserter. The mean distance between the IUD and the endometrial verge immediately post-insertion was 5.8 mm (range, 0–31; N = 80); this distance at follow-up was also 5.8 mm (range, 0–25; n = 50). Complete expulsion was observed in 6 cases (7.5%), and asymptomatic partial expulsion in 8 cases (10%). Providers reported the majority (93%, n = 74) of insertions to be easy. The majority (74%, n = 59) of participants reported the same level of pain before and after insertion. Conclusions: This dedicated PPIUD inserter performed as intended and was found to be safe, with high acceptability among the participants and providers. Further study and use of the dedicated inserter may reveal reduced risk of infection among PPIUD users as well as increased convenience compared with standard PPIUD insertion

  4. Ethane and propane emissions to the ocean and atmosphere from 550-1200 m seeps in the Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Solomon, E. A.; Kastner, M.; Leifer, I.

    2009-12-01

    Ethane (C2) and propane (C3) are highly reactive trace gases in the atmosphere that are important precursors of organic aerosols and contribute to ozone formation. The global flux of C2 and C3 based on tropospheric removal are 13-15.5 and 12 Tg/yr, respectively. Current emission inventories that include fossil fuel, biomass burning, biofuels, and waste treatment underestimate the global flux by ~2-5 Tg/yr. Previous studies have indicated that the open ocean contributes only marginally to global C2 and C3 budgets, but very few studies have investigated the natural emissions from marine seeps and their potential significance to global C2 and C3 fluxes. During a recent study at 3 seeps at depths from 550-600 m in the Gulf of Mexico (GOM), a submersible was used to collect water column samples immediately adjacent to 5 bubble plumes from the seafloor vents to the sea surface. Bottom water C2 and C3 concentrations above the seeps ranged from 24.3-2220 and 15.8-385 nM, respectively. Ethane and propane concentrations decrease by ~50-95% in the bottom 200 m. Mixed layer C2 and C3 concentrations were extremely high ranging from 6.3-147 and 4.0-110 nM. These mixed layer C2 and C3 concentrations are up to 1×105 and 5×105 times saturation with respect to atmospheric equilibrium. In general, C1/C2 and C2/C3 ratios decrease from the seafloor to the mixed layer with surface ratios lower than previously reported from marine seeps and the ocean, indicating preferential loss of light hydrocarbons from the plumes during water column transit. Preliminary results from numerical bubble models show the importance of bubble plume-driven upwelling flows, bubble size, and pressure effects for enhancing hydrocarbon transfer to the mixed layer. Based on contemporaneous wind speeds at the study sites, preliminary estimates for the diffusive C2 and C3 fluxes to the atmosphere above the seeps range from 10-400 μmol/m2d; 2-4 orders of magnitude greater than estimates from the open ocean

  5. TECHNICAL JUSTIFICATION FOR CHOOSING PROPANE AS A CALIBRATION AGENT FOR TOTAL FLAMMABLE VOLATILE ORGANIC COMPOUND (VOC) DETERMINATIONS

    SciTech Connect

    DOUGLAS, J.G.

    2006-07-06

    This document presents the technical justification for choosing and using propane as a calibration standard for estimating total flammable volatile organic compounds (VOCs) in an air matrix. A propane-in-nitrogen standard was selected based on a number of criteria: (1) has an analytical response similar to the VOCs of interest, (2) can be made with known accuracy and traceability, (3) is available with good purity, (4) has a matrix similar to the sample matrix, (5) is stable during storage and use, (6) is relatively non-hazardous, and (7) is a recognized standard for similar analytical applications. The Waste Retrieval Project (WRP) desires a fast, reliable, and inexpensive method for screening the flammable VOC content in the vapor-phase headspace of waste containers. Table 1 lists the flammable VOCs of interest to the WRP. The current method used to determine the VOC content of a container is to sample the container's headspace and submit the sample for gas chromatography--mass spectrometry (GC-MS) analysis. The driver for the VOC measurement requirement is safety: potentially flammable atmospheres in the waste containers must be allowed to diffuse prior to processing the container. The proposed flammable VOC screening method is to inject an aliquot of the headspace sample into an argon-doped pulsed-discharge helium ionization detector (Ar-PDHID) contained within a gas chromatograph. No actual chromatography is performed; the sample is transferred directly from a sample loop to the detector through a short, inert transfer line. The peak area resulting from the injected sample is proportional to the flammable VOC content of the sample. However, because the Ar-PDHID has different response factors for different flammable VOCs, a fundamental assumption must be made that the agent used to calibrate the detector is representative of the flammable VOCs of interest that may be in the headspace samples. At worst, we desire that calibration with the selected calibrating

  6. A novel predictive model for formation enthalpies of Si and Ge hydrides with propane- and butane-like structures.

    PubMed

    Weng, C; Kouvetakis, J; Chizmeshya, A V G

    2011-04-15

    Butane- and propane-like silicon-germanium hydrides and chlorinated derivatives represent a new class of precursors for the fabrication of novel metastable materials at low-temperature regimes compatible with selective growth and commensurate with the emerging demand for the reduced thermal budgets of complementary metal oxide semiconductor integration. However, predictive simulation studies of the growth process and reaction mechanisms of these new compounds, needed to accelerate their deployment and fine-tune the unprecedented low-temperature and low-pressure synthesis protocols, require experimental thermodynamic data, which are currently unavailable. Furthermore, traditional quantum chemistry approaches lack the accuracy needed to treat large molecules containing third-row elements such as Ge. Accordingly, here we develop a method to accurately predict the formation enthalpy of these compounds using atom-wise corrections for Si, Ge, Cl, and H. For a test set of 15 well-known hydrides of Si and Ge and their chlorides, such as Si(3)H(8), Ge(2)H(6), SiGeH(6), SiHCl(3), and GeCl(4), our approach reduces the deviations between the experimental and predicted formation enthalpies obtained from complete basis set (CBS-QB3), G2, and B3LPY thermochemistry to levels of 1-3 kcal/mol, or a factor of ∼5 over the corresponding uncorrected values. We show that our approach yields results comparable or better than those obtained using homodesmic reactions while circumventing the need for thermochemical data of the associated reaction species. Optimized atom-wise corrections are then used to generate accurate enthalpies of formation for 39 pure Si-Ge hydrides and a selected group of 20 chlorinated analogs, of which some have recently been synthesized for the first time. Our corrected enthalpies perfectly reproduce the experimental stability trends of heavy butane-like compounds containing Ge. This is in contrast to the direct application of the CBS-QB3 method, which yields

  7. Cobalt(II) chloride adducts with acetonitrile, propan-2-ol and tetrahydrofuran: considerations on nuclearity, reactivity and synthetic applications.

    PubMed

    Stinghen, Danilo; Rüdiger, André Luis; Giese, Siddhartha O K; Nunes, Giovana G; Soares, Jaísa F; Hughes, David L

    2017-02-01

    High-spin cobalt(II) complexes are considered useful building blocks for the synthesis of single-molecule magnets (SMM) because of their intrinsic magnetic anisotropy. In this work, three new cobalt(II) chloride adducts with labile ligands have been synthesized from anhydrous CoCl2, to be subsequently employed as starting materials for heterobimetallic compounds. The products were characterized by elemental, spectroscopic (EPR and FT-IR) and single-crystal X-ray diffraction analyses. trans-Tetrakis(acetonitrile-κN)bis(tetrahydrofuran-κO)cobalt(II) bis[(acetonitrile-κN)trichloridocobaltate(II)], [Co(C2H3N)4(C4H8O)2][CoCl3(C2H3N)]2, (1), comprises mononuclear ions and contains both acetonitrile and tetrahydrofuran (thf) ligands, The coordination polymer catena-poly[[tetrakis(propan-2-ol-κO)cobalt(II)]-μ-chlorido-[dichloridocobalt(II)]-μ-chlorido], [Co2Cl4(C3H8O)4], (2'), was prepared by direct reaction between anhydrous CoCl2 and propan-2-ol in an attempt to rationalize the formation of the CoCl2-alcohol adduct (2), probably CoCl2(HO(i)Pr)m. The binuclear complex di-μ-chlorido-1:2κ(4)Cl:Cl-dichlorido-2κ(2)Cl-tetrakis(tetrahydrofuran-1κO)dicobalt(II), [Co2Cl4(C4H8O)4], (3), was obtained from (2) after recrystallization from tetrahydrofuran. All three products present cobalt(II) centres in both octahedral and tetrahedral environments, the former usually less distorted than the latter, regardless of the nature of the neutral ligand. Product (2') is stabilized by an intramolecular hydrogen-bond network that appears to favour a trans arrangement of the chloride ligands in the octahedral moiety; this differs from the cis disposition found in (3). The expected easy displacement of the bound solvent molecules from the metal coordination sphere makes the three compounds good candidates for suitable starting materials in a number of synthetic applications.

  8. Effect of primary-zone water injection on pollutants from a combustor burning liquid ASTM A-1 and vaporized propane fuels

    NASA Technical Reports Server (NTRS)

    Ingebo, R. D.; Norgren, C. T.

    1973-01-01

    A combustor segment 0.457 meter (18 in.) long with a maximum cross section of 0.153 by 0.305 meter (6 by 12 in.) was operated at inlet-air temperatures of 590 and 700 K, inlet-air pressures of 4 and 10 atmospheres, and fuel-air ratios of 0.014 and 0.018 to determine the effect of primary-zone water injection on pollutants from burning either propane or ASTM A-1 fuel. At a simulated takeoff condition of 10 atmospheres and 700 K, multiple-orifice nozzles used to inject water at 1 percent of the airflow rate reduced nitrogen oxides 75 percent with propane and 65 percent with ASTM A-1 fuel. Although carbon monoxide and unburned hydrocarbons increased with water injection, they remained relatively low; and smoke numbers were well below the visibility limit.

  9. Nanostructure of Solid Precipitates Obtained by Expansion of Polystyrene-block-Polybutadiene Solutions in Near Critical Propane: Block Ratio and Micellar Solution Effects

    SciTech Connect

    Green, Jade; Tyrrell, Zachary; Radosz, Maciej; Hong, Kunlun; Mays, Jimmy

    2011-01-01

    In contrast to incompressible liquid solutions, compressible near-critical solutions of block copolymers allow for controlling rapid structure transformations with pressure alone. For example, when dissolved in near-critical propane, polystyrene-block-polybutadiene can form a random molecular solution at high pressures, a micellar solution at moderate pressures, and a solvent-free precipitate at low pressures. In contrast to the unstructured virgin copolymer, such a propane-treated precipitate rapidly self-assembles toward structures characteristic of equilibrated block copolymers, such as lamellae, spheres, or cylinders, which depend on the block ratio rather than on the decompression rate or temperature, at least within the rate and temperature ranges investigated in this work. At lower temperatures, however, say below 40 C, glass transition of the styrene-butadiene diblocks can inhibit independent structure formation, while crystallization of their hydrogenated-butadiene analogues can preserve the micellar-solution structure.

  10. [Investigation of a gas chromatographic column system for the on-line analysis of gaseous components in de-propane tower of pyrolysis equipment].

    PubMed

    Cai, H; Liu, L J; Yan, J; Lu, X; Ye, F; Xu, G W

    2000-03-01

    Multi-dimensional gas chromatograph has become an important process analyzer due to the advantages of high resolution and fast speed. According to the production requirement, a gas chromatographic column switching system has been investigated for the on-line analysis of gaseous components from high-pressure and lower-pressure de-propane towers of pyrolysis equipment. By using two different injection times on three injectors, and fore-flush and back-flush techniques, C2-hydrocarbons, propane, propene, methylacetylene, propadiene and C4-hydrocarbons can be separated on 7 columns in 7 minutes. The practical application showed the developed column system is suitable for the on-line monitoring of the production process.

  11. The use of two-phase molecular dynamics simulations to determine the phase behavior and critical point of propane molecular models.

    PubMed

    Patel, Sonal; Wilding, W Vincent; Rowley, Richard L

    2011-01-14

    Molecular dynamics simulations were performed to determine two-phase configurations of model propane molecules below the critical point and in the near-critical, two-phase region. A postprocessor that uses a Monte Carlo method for determination of volumes attributable to each molecule was used to obtain density histograms of the particles from which the bulk coexisting equilibrium vapor and liquid densities were determined. This method of analyzing coexisting densities in a two-phase simulation is straightforward and can be easily implemented for complex, multisite models. Various degrees of internal flexibility in the propane models have little effect on the coexisting densities at temperatures 40 K or more below the critical point, but internal flexibility (angle bending and bond vibrations) does affect the saturated liquid densities in the near-critical region, changing the critical temperature by approximately 20 K. Shorter cutoffs were also found to affect the phase dome and the location of the critical point.

  12. Characterization of the Initial Reactions during the Cometabolic Oxidation of Methyl tert-Butyl Ether by Propane-Grown Mycobacterium vaccae JOB5

    PubMed Central

    Smith, Christy A.; O'Reilly, Kirk T.; Hyman, Michael R.

    2003-01-01

    The initial reactions in the cometabolic oxidation of the gasoline oxygenate, methyl tert-butyl ether (MTBE), by Mycobacterium vaccae JOB5 have been characterized. Two products, tert-butyl formate (TBF) and tert-butyl alcohol (TBA), rapidly accumulated extracellularly when propane-grown cells were incubated with MTBE. Lower rates of TBF and TBA production from MTBE were also observed with cells grown on 1- or 2-propanol, while neither product was generated from MTBE by cells grown on casein-yeast extract-dextrose broth. Kinetic studies with propane-grown cells demonstrated that TBF is the dominant (≥80%) initial product of MTBE oxidation and that TBA accumulates from further biotic and abiotic hydrolysis of TBF. Our results suggest that the biotic hydrolysis of TBF is catalyzed by a heat-stable esterase with activity toward several other tert-butyl esters. Propane-grown cells also oxidized TBA, but no further oxidation products were detected. Like the oxidation of MTBE, TBA oxidation was fully inhibited by acetylene, an inactivator of short-chain alkane monooxygenase in M. vaccae JOB5. Oxidation of both MTBE and TBA was also inhibited by propane (Ki = 3.3 to 4.4 μM). Values for Ks of 1.36 and 1.18 mM and for Vmax of 24.4 and 10.4 nmol min−1 mg of protein−1 were derived for MTBE and TBA, respectively. We conclude that the initial steps in the pathway of MTBE oxidation by M. vaccae JOB5 involve two reactions catalyzed by the same monooxygenase (MTBE and TBA oxidation) that are temporally separated by an esterase-catalyzed hydrolysis of TBF to TBA. These results that suggest the initial reactions in MTBE oxidation by M. vaccae JOB5 are the same as those that we have previously characterized in gaseous alkane-utilizing fungi. PMID:12570997

  13. Comparison of two-body and three-body decomposition of ethanedial, propanal, propenal, n-butane, 1-butene, and 1,3-butadiene

    NASA Astrophysics Data System (ADS)

    Chin, Chih-Hao; Lee, Shih-Huang

    2012-01-01

    We investigated two-body (binary) and three-body (triple) dissociations of ethanedial, propanal, propenal, n-butane, 1-butene, and 1,3-butadiene on the ground potential-energy surfaces using quantum-chemical and Rice-Ramsperger-Kassel-Marcus calculations; most attention is paid on the triple dissociation mechanisms. The triple dissociation includes elimination of a hydrogen molecule from a combination of two separate terminal hydrogen atoms; meanwhile, the rest part simultaneously decomposes to two stable fragments, e.g., C2H4, C2H2, or CO. Transition structures corresponding to the concerted triple dissociation were identified using the B3LYP/6-311G(d,p) level of theory and total energies were computed using the method CCSD(T)/6-311+G(3df, 2p). The forward barrier height of triple dissociation has a trend of ethanedial < propanal < propenal < n-butane < 1-butene < 1,3-butadiene, pertaining to the reaction enthalpy. Ratios of translational energies of three separate fragments could be estimated from the transition structure of triple dissociation. The synchronous concerted dissociation of propanal, propenal, and 1-butene leading to three different types of molecular fragments by breaking nonequivalent chemical bonds is rare. The triple dissociation of propanal, n-butane, 1-butene, and 1,3-butadiene were investigated for the first time. To outline a whole picture of dissociation mechanisms, some significant two-body dissociation channels were investigated for the calculations of product branching ratios. The triple dissociation plays an important role in the three carbonyl compounds, but plays a minor or negligible role in the three hydrocarbons.

  14. Comparison of two-body and three-body decomposition of ethanedial, propanal, propenal, n-butane, 1-butene, and 1,3-butadiene.

    PubMed

    Chin, Chih-Hao; Lee, Shih-Huang

    2012-01-14

    We investigated two-body (binary) and three-body (triple) dissociations of ethanedial, propanal, propenal, n-butane, 1-butene, and 1,3-butadiene on the ground potential-energy surfaces using quantum-chemical and Rice-Ramsperger-Kassel-Marcus calculations; most attention is paid on the triple dissociation mechanisms. The triple dissociation includes elimination of a hydrogen molecule from a combination of two separate terminal hydrogen atoms; meanwhile, the rest part simultaneously decomposes to two stable fragments, e.g., C(2)H(4), C(2)H(2), or CO. Transition structures corresponding to the concerted triple dissociation were identified using the B3LYP/6-311G(d,p) level of theory and total energies were computed using the method CCSD(T)/6-311+G(3df, 2p). The forward barrier height of triple dissociation has a trend of ethanedial < propanal < propenal < n-butane < 1-butene < 1,3-butadiene, pertaining to the reaction enthalpy. Ratios of translational energies of three separate fragments could be estimated from the transition structure of triple dissociation. The synchronous concerted dissociation of propanal, propenal, and 1-butene leading to three different types of molecular fragments by breaking nonequivalent chemical bonds is rare. The triple dissociation of propanal, n-butane, 1-butene, and 1,3-butadiene were investigated for the first time. To outline a whole picture of dissociation mechanisms, some significant two-body dissociation channels were investigated for the calculations of product branching ratios. The triple dissociation plays an important role in the three carbonyl compounds, but plays a minor or negligible role in the three hydrocarbons.

  15. Platinum-Promoted Ga/Al2O3 as Highly Active, Selective, and Stable Catalyst for the Dehydrogenation of Propane**

    PubMed Central

    Sattler, Jesper J H B; Gonzalez-Jimenez, Ines D; Luo, Lin; Stears, Brien A; Malek, Andrzej; Barton, David G; Kilos, Beata A; Kaminsky, Mark P; Verhoeven, Tiny W G M; Koers, Eline J; Baldus, Marc; Weckhuysen, Bert M

    2014-01-01

    A novel catalyst material for the selective dehydrogenation of propane is presented. The catalyst consists of 1000 ppm Pt, 3 wt % Ga, and 0.25 wt % K supported on alumina. We observed a synergy between Ga and Pt, resulting in a highly active and stable catalyst. Additionally, we propose a bifunctional active phase, in which coordinately unsaturated Ga3+ species are the active species and where Pt functions as a promoter. PMID:24989975

  16. Effect of varying the combustion parameters on the emissions of carbon monoxide and nitrogen oxides in the exhaust gases from propane-fueled vehicles.

    PubMed

    Roberge, B

    2000-05-01

    Propane-fueled forklifts are one source of carbon monoxide (CO) contamination of workplace air. The previous study carried out by the Quebec Occupational Health and Safety Research Institute dealt with worker exposure to CO during forklift use in buildings. It recommends that exhaust gas emissions be kept below a 1 percent concentration. However, this control has not produced a significant reduction in worker exposure to CO, when factors (ventilation, type of work tasks, and management of vehicle fleet) specific to companies are taken into account. Consequently, a reduction in CO emissions below the threshold of 0.3 percent should be considered. The experience acquired with propane-fueled ice resurfacers can be used to determine the effect of combustion parameters on exhaust gas emissions. It is known that a reduction in CO emissions from ice resurfacers resulted in the appearance of nitrogen oxides (NOx) and eventually in nitrogen dioxide (NO2) poisoning. Few publications present NOx results in relation to the CO measured in the exhaust gases of propane-fueled vehicles. The objective of this study is to define the level to which CO emissions can be reduced without increasing NOx concentrations. This real-situation study quantified the CO, NO, and NOx in the exhaust gases of a fleet of propane-fueled forklifts in relation to the mixture ratio. The results show the impact of the motor speed and mixture ratio on the CO, NO, and NO2 concentrations. They confirm an increase in NOx concentrations when CO concentrations are reduced. They also show that proper maintenance of forklifts combined with optimal adjustments can reduce CO and NOx emissions. The study proposes a compromise between CO and NOx emissions by taking into account worker health and safety as well as vehicle performance. Monitoring must be done to control air quality in work areas and worker exposure to CO and NO2. A forklift preventive maintenance program and general building ventilation are the favored

  17. Effects of pressure, temperature, and hydrogen during graphene growth on SiC(0001) using propane-hydrogen chemical vapor deposition

    SciTech Connect

    Michon, A.; Vezian, S.; Roudon, E.; Lefebvre, D.; Portail, M.; Zielinski, M.; Chassagne, T.

    2013-05-28

    Graphene growth from a propane flow in a hydrogen environment (propane-hydrogen chemical vapor deposition (CVD)) on SiC differentiates from other growth methods in that it offers the possibility to obtain various graphene structures on the Si-face depending on growth conditions. The different structures include the (6{radical}3 Multiplication-Sign 6{radical}3)-R30 Degree-Sign reconstruction of the graphene/SiC interface, which is commonly observed on the Si-face, but also the rotational disorder which is generally observed on the C-face. In this work, growth mechanisms leading to the formation of the different structures are studied and discussed. For that purpose, we have grown graphene on SiC(0001) (Si-face) using propane-hydrogen CVD at various pressure and temperature and studied these samples extensively by means of low energy electron diffraction and atomic force microscopy. Pressure and temperature conditions leading to the formation of the different structures are identified and plotted in a pressure-temperature diagram. This diagram, together with other characterizations (X-ray photoemission and scanning tunneling microscopy), is the basis of further discussions on the carbon supply mechanisms and on the kinetics effects. The entire work underlines the important role of hydrogen during growth and its effects on the final graphene structure.

  18. Effects of heat loss, preferential diffusion, and flame stretch on flame-front instability and extinction of propane/air mixtures

    NASA Technical Reports Server (NTRS)

    Ishizuka, S.; Miyasaka, K.; Law, C. K.

    1982-01-01

    Flame configurations, flame-front cellular instability, and extinction of propane/air mixtures in the stagnation-point flow are experimentally studied for their dependence on downstream heat loss, preferential diffusion, and flame stretch. Boundaries for lean- and rich-limit extinction, stabilization of corrugated flames, and local extinction caused by sharp curvatures are mapped for varying propane concentrations and freestream velocities. Flame location and temperature at extinction are determined as functions of stagnation surface temperature, extent of preheating, propane concentration, and freestream velocity. Results substantiate the theoretical predictions of the different extinction modes for lean and rich flames in the absence of downstream heat loss, and yield useful insight on the extinction characteristics when finite downstream heat loss does exist. It is further shown that flame-front instability occurs only for rich mixtures in accordance with preferential diffusion considerations, and that flame stretch has a stabilizing effect such that flame-front instability is completely inhibited before the onset of extinction.

  19. Relationship between Surface Chemistry and Catalytic Performance of Mesoporous γ-Al2O3 Supported VOX Catalyst in Catalytic Dehydrogenation of Propane.

    PubMed

    Bai, Peng; Ma, Zhipeng; Li, Tingting; Tian, Yupeng; Zhang, Zhanquan; Zhong, Ziyi; Xing, Wei; Wu, Pingping; Liu, Xinmei; Yan, Zifeng

    2016-10-05

    Mesoporous γ-Al2O3 was synthesized via a cation-anion double hydrolysis approach (CADH). The synthesized mesoporous alumina displayed a relatively high surface area, a large pore volume and a narrow pore size distribution. By applying the mesoporous alumina as a support, supported vanadium catalysts were prepared and evaluated in the dehydrogenation of propane, exhibiting a superior catalytic performance over that supported on a commercial alumina. Materials were characterized with a variety of techniques such as X-ray diffraction, X-ray photoelectron spectroscopy, ultraviolet-visible spectroscopy, (51)V magnetic angle spinning nuclear magnetic resonance, Raman spectroscopy, Fourier transformed infrared spectroscopy of pyridine adsorption and thermogravimetric-differential thermal analysis. The correlated structure-performance relationship of catalysts reveals that a higher crystallization temperature endows mesoporous alumina materials with more surface acid sites, favoring the formation of polymerized VOX species, which are more active than isolated ones in the propane dehydrogenation, resulting in a better catalytic performance. The established relationship between surface chemistry and catalytic performance of supported VOX catalysts suggests that a superior vanadium catalyst for propane dehydrogenation could be achieved by rationally enriching the concentration of polymeric VOX species on the catalyst, which can be realized by tuning the surface acidity of alumina support.

  20. Promotion of Ag/H-BEA by Mn for lean NO reduction with propane at low temperature.

    PubMed

    Pan, Hua; Su, Qingfa; Chen, Jie; Ye, Qing; Liu, Yiting; Shi, Yao

    2009-12-15

    Effects of adding manganese to Ag/H-BEA for selective catalytic reduction of NO(x) with propane (C(3)H(8)-SCR) were investigated under a lean-burn condition. Mn addition significantly promotes the catalytic performance of Ag/H-BEA below 673 K. A Ag-Mn/H-BEA catalyst with equal metal weight of 3 wt % has the highest activity for C(3)H(8)-SCR among samples with a different bimetal loading. Manganese is mainly present in the 3+ and 4+ oxidation states in Ag-Mn/H-BEA catalysts. The major contributions of manganese suggested by the data presented in this paper are to catalyze the NO oxidation and stabilize silver in a dispersed Ag(+) state. The presence of silver enforces the transformation of a certain amount of Mn(3+) ions to Mn(4+) ions. The activity of Ag-Mn/H-BEA decreases slightly at low SO(2) concentrations (0-200 ppm) but decreases significantly at high SO(2) concentrations (400-800 ppm). In the presence of 10% H(2)O and 200 ppm SO(2), the inhibition of C(3)H(8)-SCR below 673 K is more significant than that at high temperature above 673 K. Ag-Mn/H-BEA is a promising catalyst for the removal of NO(x) from diesel engine exhaust.

  1. Activation of Propane C-H and C-C Bonds by Gas-Phase Pt Atom: A Theoretical Study

    PubMed Central

    Li, Fang-Ming; Yang, Hua-Qing; Ju, Ting-Yong; Li, Xiang-Yuan; Hu, Chang-Wei

    2012-01-01

    The reaction mechanism of the gas-phase Pt atom with C3H8 has been systematically investigated on the singlet and triplet potential energy surfaces at CCSD(T)//BPW91/6-311++G(d, p), Lanl2dz level. Pt atom prefers the attack of primary over secondary C-H bonds in propane. For the Pt + C3H8 reaction, the major and minor reaction channels lead to PtC3H6 + H2 and PtCH2 + C2H6, respectively, whereas the possibility to form products PtC2H4 + CH4 is so small that it can be neglected. The minimal energy reaction pathway for the formation of PtC3H6 + H2, involving one spin inversion, prefers to start at the triplet state and afterward proceed along the singlet state. The optimal C-C bond cleavages are assigned to C-H bond activation as the first step, followed by cleavage of a C-C bond. The C-H insertion intermediates are kinetically favored over the C-C insertion intermediates. From C-C to C-H oxidative insertion, the lowering of activation barrier is mainly caused by the more stabilizing transition state interaction ΔE≠int, which is the actual interaction energy between the deformed reactants in the transition state. PMID:22942766

  2. Effect of heat recirculation on the self-sustained catalytic combustion of propane/air mixtures in a quartz reactor

    SciTech Connect

    Scarpa, A.; Pirone, R.; Russo, G.; Vlachos, D.G.

    2009-05-15

    The self-sustained catalytic combustion of propane is experimentally studied in a two-pass, quartz heat-recirculation reactor (HRR) and compared to that in a no (heat) recirculation reactor (NRR). Structured monolithic reactors with Pt/{gamma}-Al{sub 2}O{sub 3}, LaMnO{sub 3}/{gamma}-Al{sub 2}O{sub 3}, and Pt doped perovskite catalysts have been compared in the HRR and NRR configurations. Heat recirculation enhances combustion stability, by widening the operating window of self-sustained operation, and changes the mode of stability loss from blowout to extinction. It is found that thermal shields (upstream and downstream of the monolith) play no role in the stability of a HRR but increase the stability of a NRR. The stability of a HRR follows this trend: Pt/{gamma}-Al{sub 2}O{sub 3} > doped perovskite > LaMnO{sub 3}/{gamma}-Al{sub 2}O{sub 3}. Finally, a higher cell density monolith enlarges the operating window of self-sustained combustion, and allows further increase of the power density of the process. (author)

  3. Laboratory studies, analysis, and interpretation of the spectra of hydrocarbons present in planetary atmospheres including cyanoacetylene, acetylene, propane, and ethane

    NASA Technical Reports Server (NTRS)

    Blass, William E.; Daunt, Stephen J.; Peters, Antoni V.; Weber, Mark C.

    1990-01-01

    Combining broadband Fourier transform spectrometers (FTS) from the McMath facility at NSO and from NRC in Ottawa and narrow band TDL data from the laboratories with computational physics techniques has produced a broad range of results for the study of planetary atmospheres. Motivation for the effort flows from the Voyager/IRIS observations and the needs of Voyager analysis for laboratory results. In addition, anticipation of the Cassini mission adds incentive to pursue studies of observed and potentially observable constituents of planetary atmospheres. Current studies include cyanoacetylene, acetylene, propane, and ethane. Particular attention is devoted to cyanoacetylen (H3CN) which is observed in the atmosphere of Titan. The results of a high resolution infrared laboratory study of the line positions of the 663, 449, and 22.5/cm fundamental bands are presented. Line position, reproducible to better than 5 MHz for the first two bands, are available for infrared astrophysical searches. Intensity and broadening studies are in progress. Acetylene is a nearly ubiquitous atmospheric constituent of the outer planets and Titan due to the nature of methane photochemistry. Results of ambient temperature absolute intensity measurements are presented for the fundamental and two two-quantum hotband in the 730/cm region. Low temperature hotband intensity and linewidth measurements are planned.

  4. Temperature programmed oxidation of coked H-gallosilicate (MFI) propane aromatization catalyst: Influence of catalyst composition and pretreatment parameters

    SciTech Connect

    Choudhary, V.R.; Devadas, P.; Sansare, S.D.; Guisnet, M.

    1997-03-01

    Temperature programmed oxidation (TPO) of H-gallosilicate (MFI) coked in the propane aromatization at 550{degrees}C for a time-on-stream of 7-8 h has been investigated by measuring point to point the consumption of oxygen and also the formation of the both CO and CO{sub 2} (by GC analysis using a 16-loop gas sampling valve) during the TPO run from 50{degrees} to 900{degrees}C at a linear heating rate of 20{degrees}C min{sup -1} in a flow (50 cm{sup 3} min{sup -1}) of a O{sub 2}-He mixture (8.0 mol% O{sub 2}). The SiGa and Na/Ga ratios, calcination temperature, and hydrothermal pretreatments of the zeolite and also the presence of binder (silica or kaolin) in the catalyst have a strong influence on the TPO of coked zeolite. The influence is attributed to changes in the zeolite properties (viz., zeolitic acidity or framework Ga and non-GW Ga-oxide species), which affect the coke oxidation both directly and/or indirectly, by controlling the nature of coke formed during the coking process. 23 refs., 4 figs., 2 tabs.

  5. Cooling rate and ice-crystal measurement in biological specimens plunged into liquid ethane, propane, and Freon 22.

    PubMed

    Ryan, K P; Bald, W B; Neumann, K; Simonsberger, P; Purse, D H; Nicholson, D N

    1990-06-01

    Specimens sandwiched between copper planchettes were plunged up to a depth of 430 mm into coolants used for cryofixation. Hydrated gelatin containing a miniature thermocouple was used to mimic the behaviour of tissue during freezing. Gelatin and red blood cells were used for ice-crystal analysis. Ethane produced the fastest cooling rates and the smallest ice-crystal profiles, and Freon 22 produced the slowest cooling rates and the largest crystal profiles. Smaller crystal profiles were often seen in the centre of the specimens than in subsurface zones. The results show that ethane, rather than propane, should be used for freezing metal-sandwiched freeze-fracture specimens by the plunging method, and probably also in the jet-cooling method. They further suggest that good cryofixation could occur at the centre of thin specimens rather than only at their surfaces. Comparison between theoretical and experimental ice-crystal sizes was satisfactory, indicating that where the experimental parameters can be defined then realistic predictions can be made regarding cryofixation results.

  6. Reversal of global atmospheric ethane and propane trends largely due to US oil and natural gas production

    NASA Astrophysics Data System (ADS)

    Helmig, Detlev; Rossabi, Samuel; Hueber, Jacques; Tans, Pieter; Montzka, Stephen A.; Masarie, Ken; Thoning, Kirk; Plass-Duelmer, Christian; Claude, Anja; Carpenter, Lucy J.; Lewis, Alastair C.; Punjabi, Shalini; Reimann, Stefan; Vollmer, Martin K.; Steinbrecher, Rainer; Hannigan, James W.; Emmons, Louisa K.; Mahieu, Emmanuel; Franco, Bruno; Smale, Dan; Pozzer, Andrea

    2016-07-01

    Non-methane hydrocarbons such as ethane are important precursors to tropospheric ozone and aerosols. Using data from a global surface network and atmospheric column observations we show that the steady decline in the ethane mole fraction that began in the 1970s halted between 2005 and 2010 in most of the Northern Hemisphere and has since reversed. We calculate a yearly increase in ethane emissions in the Northern Hemisphere of 0.42 (+/-0.19) Tg yr-1 between mid-2009 and mid-2014. The largest increases in ethane and the shorter-lived propane are seen over the central and eastern USA, with a spatial distribution that suggests North American oil and natural gas development as the primary source of increasing emissions. By including other co-emitted oil and natural gas non-methane hydrocarbons, we estimate a Northern Hemisphere total non-methane hydrocarbon yearly emission increase of 1.2 (+/-0.8) Tg yr-1. Atmospheric chemical transport modelling suggests that these emissions could augment summertime mean surface ozone by several nanomoles per mole near oil and natural gas production regions. Methane/ethane oil and natural gas emission ratios could suggest a significant increase in associated methane emissions; however, this increase is inconsistent with observed leak rates in production regions and changes in methane's global isotopic ratio.

  7. Supramolecular structural, thermal properties and biological activity of 3-(2-methoxyphenoxy)propane-1,2-diol metal complexes

    NASA Astrophysics Data System (ADS)

    Mahmoud, Walaa H.; Mahmoud, Nessma F.; Mohamed, Gehad G.; El-Bindary, Ashraf A.; El-Sonbati, Adel Z.

    2015-04-01

    New bi- and trivalent transition metal complexes of ligand 3-(2-methoxyphenoxy)propane-1,2-diol (GFS) were synthesized. The ligand and complexes were characterized via: melting point, UV/Visible, IR, 1H NMR, mass and diffused reflectance spectroscopy. The molecular structure of the investigated ligand (GFS) is optimized theoretically and the quantum chemical parameters are calculated. In addition, the complexes were characterized based on conductivity measurement, thermal analysis and biological activity. The infrared spectral study of GFS and its complexes, act as monobasic tridentate through the oxygen atom of hydroxyl group and two etheric oxygen atoms. Also, coordination to the unprotonated oxygen is evidenced from the disappearance of the OH signal in the 1H NMR spectra after complexation. The thermogravimetric analysis of the complexes shows metal oxide remaining as the final product. The compounds were tested against four bacterial species; two Gram positive bacteria (Bacillus subtilis and Staphylococcus aureus) and two Gram negative bacteria (Escherichia coli and Pseudomonas aeruginosa) as well as antifungal activity against (Candida albicans). The complexes showed significant activities against Gram positive bacteria than Gram negative bacteria. [Cd(GFS)Cl(H2O)2] complex showed remarkable antifungal activity. However, some complexes showed more chemotherapeutic efficiency than the parent GFS drug. The drug and complexes were also screened for their in vitro anticancer activity against the Breast cell line (MFC7) and the results obtained show that they exhibit a considerable anticancer activity.

  8. A Dedicated Inferior Vena Cava Filter Service Line: How to Optimize Your Practice.

    PubMed

    Karp, Jennifer K; Desai, Kush R; Salem, Riad; Ryu, Robert K; Lewandowski, Robert J

    2016-06-01

    Despite the increased placement of retrievable inferior vena cava filters (rIVCFs), efforts to remove these devices are not commensurate. The majority of rIVCFs are left in place beyond their indicated usage, and often are retained permanently. With a growing understanding of the clinical issues associated with these devices, the United States Food and Drug Administration (FDA) has prompted clinicians to remove rIVCF when they are no longer indicated. However, major obstacles exist to filter retrieval, chief among them being poor clinical follow-up. The establishment of a dedicated IVC filter service line, or clinic, has been shown to improve filter retrieval rates. Usage of particular devices, specifically permanent versus retrievable filters, is enhanced by prospective physician consultation. In this article, the rationale behind a dedicated IVC filter service line is presented as well as described the structure and activities of the authors' IVC filter clinic; supporting data will also be provided when appropriate.

  9. Earth Viewing Applications Laboratory (EVAL). Dedicated payload, standard test rack payload, sensor modifications

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The preliminary analysis of strawman earth-viewing shuttle sortie payloads begun with the partial spacelab payload was analyzed. The payloads analyzed represent the two extremes of shuttle sortie application payloads: a full shuttle sortie payload dedicated to earth-viewing applications, and a small structure payload which can fly on a space available basis with another primary shuttle payload such as a free flying satellite. The intent of the dedicated mission analysis was to configure an ambitious, but feasible, payload; which, while rich in scientific return, would also stress the system and reveal any deficiences or problem areas in mission planning, support equipment, and operations. Conversely, the intent of the small structure payload was to demonstrate the ease with which a small, simple, flexible payload can be accommodated on shuttle flights.

  10. Distributed computing feasibility in a non-dedicated homogeneous distributed system

    NASA Technical Reports Server (NTRS)

    Leutenegger, Scott T.; Sun, Xian-He

    1993-01-01

    The low cost and availability of clusters of workstations have lead researchers to re-explore distributed computing using independent workstations. This approach may provide better cost/performance than tightly coupled multiprocessors. In practice, this approach often utilizes wasted cycles to run parallel jobs. The feasibility of such a non-dedicated parallel processing environment assuming workstation processes have preemptive priority over parallel tasks is addressed. An analytical model is developed to predict parallel job response times. Our model provides insight into how significantly workstation owner interference degrades parallel program performance. A new term task ratio, which relates the parallel task demand to the mean service demand of nonparallel workstation processes, is introduced. It was proposed that task ratio is a useful metric for determining how large the demand of a parallel applications must be in order to make efficient use of a non-dedicated distributed system.

  11. WARP: Weight Associative Rule Processor. A dedicated VLSI fuzzy logic megacell

    NASA Technical Reports Server (NTRS)

    Pagni, A.; Poluzzi, R.; Rizzotto, G. G.

    1992-01-01

    During the last five years Fuzzy Logic has gained enormous popularity in the academic and industrial worlds. The success of this new methodology has led the microelectronics industry to create a new class of machines, called Fuzzy Machines, to overcome the limitations of traditional computing systems when utilized as Fuzzy Systems. This paper gives an overview of the methods by which Fuzzy Logic data structures are represented in the machines (each with its own advantages and inefficiencies). Next, the paper introduces WARP (Weight Associative Rule Processor) which is a dedicated VLSI megacell allowing the realization of a fuzzy controller suitable for a wide range of applications. WARP represents an innovative approach to VLSI Fuzzy controllers by utilizing different types of data structures for characterizing the membership functions during the various stages of the Fuzzy processing. WARP dedicated architecture has been designed in order to achieve high performance by exploiting the computational advantages offered by the different data representations.

  12. Development of a 100 nmol mol(-1) propane-in-air SRM for automobile-exhaust testing for new low-emission requirements.

    PubMed

    Rhoderick, George C

    2007-04-01

    New US federal low-level automobile emission requirements, for example zero-level-emission vehicle (ZLEV), for hydrocarbons and other species, have resulted in the need by manufacturers for new certified reference materials. The new emission requirement for hydrocarbons requires the use, by automobile manufacturing testing facilities, of a 100 nmol mol(-1) propane in air gas standard. Emission-measurement instruments are required, by federal law, to be calibrated with National Institute of Standards and Technology (NIST) traceable reference materials. Because a NIST standard reference material (SRM) containing 100 nmol mol(-1) propane was not available, the US Environmental Protection Agency (EPA) and the Automobile Industry/Government Emissions Research Consortium (AIGER) requested that NIST develop such an SRM. A cylinder lot of 30 gas mixtures containing 100 nmol mol(-1) propane in air was prepared in 6-L aluminium gas cylinders by a specialty gas company and delivered to the Gas Metrology Group at NIST. Another mixture, contained in a 30-L aluminium cylinder and included in the lot, was used as a lot standard (LS). Using gas chromatography with flame-ionization detection all 30 samples were compared to the LS to obtain the average of six peak-area ratios to the LS for each sample with standard deviations of <0.31%. The average sample-to-LS ratio determinations resulted in a range of 0.9828 to 0.9888, a spread of 0.0060, which corresponds to a relative standard deviation of 0.15% of the average for all 30 samples. NIST developed its first set of five propane in air primary gravimetric standards covering a concentration range 91 to 103 nmol mol(-1) with relative uncertainties of 0.15%. This new suite of propane gravimetric standards was used to analyze and assign a concentration value to the SRM LS. On the basis of these data each SRM sample was individually certified, furnishing the desired relative expanded uncertainty of +/-0.5%. Because automobile companies

  13. Dedicated Pediatricians in Emergency Department: Shorter Waiting Times and Lower Costs

    PubMed Central

    Melo, Manuel Rocha; Ferreira-Magalhães, Manuel; Flor-Lima, Filipa; Rodrigues, Mariana; Severo, Milton; Almeida-Santos, Luis; Caldas-Afonso, Alberto; Barros, Pedro Pita; Ferreira, António

    2016-01-01

    Background Dedicated pediatricians in emergency departments (EDs) may be beneficial, though no previous studies have assessed the related costs and benefits/harms. We aimed to evaluate the net benefits and costs of dedicated emergency pediatricians in a pediatric ED. Methods Cost-consequences analysis of visits to a pediatric ED of a tertiary hospital. Two pediatric ED Medical Teams (MT) were compared: MT-A (May–September 2012), with general pediatrics physicians only; and MT-B (May–September 2013), with emergency dedicated pediatricians. The main outcomes analyzed were relevant clinical outcomes, patient throughput time and costs. Results We included 8,694 children in MT-A and 9,417 in MT-B. Medication use in the ED increased from 42.3% of the children in MT-A to 49.6% in MT-B; diagnostic tests decreased from 24.2% in MT-A to 14.3% in MT-B. Hospitalization increased from 1.3% in MT-A to 3.0% in MT-B; however, there was no significant difference in diagnosis-related group relative weight of hospitalized children in MT-A and MT-B (MT-A, 0.979; MT-B, 1.075). No differences were observed in ED readmissions or in patients leaving without being seen by a physician. The patient throughput time was significantly shorter in MT-B, with faster times to first medical observation. Within the cost domains analyzed, the total expenditures per children observed in the ED were 16% lower in MT-B: 37.87 euros in MT-A; 31.97 euros in MT-B. Conclusion The presence of dedicated emergency pediatricians in a pediatric ED was associated with significantly lower waiting times in the ED, reduced costs, and similar clinical outcomes. PMID:27564093

  14. Additional Development of a Dedicated Liquefied Petroleum Gas (LPG) Ultra Low Emissions Vehicle (ULEV)

    SciTech Connect

    IMPCO Technologies

    1998-10-28

    This report describes the last in a series of three projects designed to develop a commercially competitive LPG light-duty passenger car that meets California ULEV standards and corporate average fuel economy (CAFE) energy efficiency guidelines for such a vehicle. In this project, IMPCO upgraded the vehicle's LPG vapor fuel injection system and performed emissions testing. The vehicle met the 1998 ULEV standards successfully, demonstrating the feasibility of meeting ULEV standards with a dedicated LPG vehicle.

  15. A minimum spanning forest based classification method for dedicated breast CT images

    SciTech Connect

    Pike, Robert; Sechopoulos, Ioannis; Fei, Baowei

    2015-11-15

    Purpose: To develop and test an automated algorithm to classify different types of tissue in dedicated breast CT images. Methods: Images of a single breast of five different patients were acquired with a dedicated breast CT clinical prototype. The breast CT images were processed by a multiscale bilateral filter to reduce noise while keeping edge information and were corrected to overcome cupping artifacts. As skin and glandular tissue have similar CT values on breast CT images, morphologic processing is used to identify the skin based on its position information. A support vector machine (SVM) is trained and the resulting model used to create a pixelwise classification map of fat and glandular tissue. By combining the results of the skin mask with the SVM results, the breast tissue is classified as skin, fat, and glandular tissue. This map is then used to identify markers for a minimum spanning forest that is grown to segment the image using spatial and intensity information. To evaluate the authors’ classification method, they use DICE overlap ratios to compare the results of the automated classification to those obtained by manual segmentation on five patient images. Results: Comparison between the automatic and the manual segmentation shows that the minimum spanning forest based classification method was able to successfully classify dedicated breast CT image with average DICE ratios of 96.9%, 89.8%, and 89.5% for fat, glandular, and skin tissue, respectively. Conclusions: A 2D minimum spanning forest based classification method was proposed and evaluated for classifying the fat, skin, and glandular tissue in dedicated breast CT images. The classification method can be used for dense breast tissue quantification, radiation dose assessment, and other applications in breast imaging.

  16. Module comprising IC memory stack dedicated to and structurally combined with an IC microprocessor chip

    NASA Technical Reports Server (NTRS)

    Carson, John C. (Inventor); Indin, Ronald J. (Inventor); Shanken, Stuart N. (Inventor)

    1994-01-01

    A computer module is disclosed in which a stack of glued together IC memory chips is structurally integrated with a microprocessor chip. The memory provided by the stack is dedicated to the microprocessor chip. The microprocessor and its memory stack may be connected either by glue and/or by solder bumps. The solder bumps can perform three functions--electrical interconnection, mechanical connection, and heat transfer. The electrical connections in some versions are provided by wire bonding.

  17. A Dedicated Environmental Remote Sensing Facility for the Columbia Earth Institute

    NASA Technical Reports Server (NTRS)

    Weissel, Jeffrey K.; Small, Christopher

    1999-01-01

    This paper presents a final technical report on a dedicated environmental remote sensing facility for the Columbia Earth Institute. The above-referenced award enabled the Lamont-Doherty Earth Observatory to establish a state-of-the-art remote sensing image analysis and data visualization facility to serve the research and educational needs of students and staff at Lamont and the Columbia Earth Institute.

  18. The effects on population health status of using dedicated property taxes to fund local public health agencies

    PubMed Central

    2011-01-01

    Background In the United States, a dedicated property tax describes the legal authority given to a local jurisdiction to levy and collect a tax for a specific purpose. We investigated for an association of locally dedicated property taxes to fund local public health agencies and improved health status in the eight states designated as the Mississippi Delta Region. Methods We analyzed the difference in health outcomes of counties with and without a dedicated public health tax after adjusting for a set of control variables using regression models for county level data from 720 counties of the Mississippi Delta Region. Results Levying a dedicated public health tax for counties with per capita income above $28,000 is associated with improved health outcomes of those counties when compared to counties without a dedicated property tax for public health. Alternatively, levying a dedicated property tax in counties with lower per capita income is associated with poor health outcomes. Conclusions There are both positive and negative consequences of using dedicated property taxes to fund public health. Policymakers should carefully examine both the positive association of improved health outcomes and negative impact of taxation on poor populations before authorizing the use of dedicated local property tax levies to fund public health agencies. PMID:21672231

  19. Addressing the Challenge of Preparing Australian Pre-Service Primary Teachers in Environmental Education: An Evaluation of a Dedicated Unit

    ERIC Educational Resources Information Center

    Kennelly, Julie; Taylor, Neil; Maxwell, T. W.

    2008-01-01

    Concerns have been raised for some time about the preparation of Australian teachers in the area of environmental education. Few tertiary institutions that undertake teacher education in Australia have specific units or modules dedicated to environmental education. This article reports on an evaluation of such a dedicated unit recently introduced…

  20. 33 CFR Appendix D to Part 157 - Example of a Procedure for Dedicated Clean Ballast Tanks Operations

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Dedicated Clean Ballast Tanks Operations D Appendix D to Part 157 Navigation and Navigable Waters COAST... ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Pt. 157, App. D Appendix D to Part 157—Example of a.... (3) Ensure that all valves in the dedicated clean ballast tanks are closed. (d) Before arrival at...

  1. Investigation of a novel image segmentation method dedicated to forest fire applications

    NASA Astrophysics Data System (ADS)

    Rudz, S.; Chetehouna, K.; Hafiane, A.; Laurent, H.; Séro-Guillaume, O.

    2013-07-01

    To face fire it is crucial to understand its behaviour in order to maximize fighting means. To achieve this task, the development of a metrological tool is necessary for estimating both geometrical and physical parameters involved in forest fire modelling. A key parameter is to estimate fire positions accurately. In this paper an image processing tool especially dedicated to an accurate extraction of fire from an image is presented. In this work, the clustering on several colour spaces is investigated and it appears that the blue chrominance Cb from the YCbCr colour space is the most appropriate. As a consequence, a new segmentation algorithm dedicated to forest fire applications has been built using first an optimized k-means clustering in the Cb-channel and then some properties of fire pixels in the RGB colour space. Next, the performance of the proposed method is evaluated using three supervised evaluation criteria and then compared to other existing segmentation algorithms in the literature. Finally a conclusion is drawn, assessing the good behaviour of the developed algorithm. This paper is dedicated to the memory of Dr Olivier Séro-Guillaume (1950-2013), CNRS Research Director.

  2. General-purpose and dedicated regimes in the use of telescopes

    NASA Astrophysics Data System (ADS)

    Lamy, Jérôme; Davoust, Emmanuel

    2009-11-01

    We propose a socio-historical framework for better understanding the evolution in the use of telescopes. We define two regimes of use: a general-purpose (or survey) one, where the telescope governs research, and a dedicated one, in which the telescope is tailored to a specific project which includes a network of other tools. This conceptual framework is first applied to the history of the 80-cm reflector at the Toulouse Observatory, which was initially anchored in a general-purpose regime linked to astrometry. After a transition in the 1930s, it was integrated into a dedicated regime centered on astrophysics. This evolution is compared to that of a very similar instrument, the 80-cm reflector at the Marseille Observatory, which was converted to a dedicated regime with the Fabry-Perot interferometer around 1910, and, after a period of idleness, was again used in the survey mode after WWII. To further validate our new concept, we apply it to the telescopes at the Washburn Observatory, the Dominion Astrophysical Observatory and the Meudon Observatory. The uses of the different telescopes illustrate various combinations of the two regimes, which can be successive, simultaneous or alternating. This conceptual framework is likely to be applicable to other fields of pure and applied science.

  3. Integrating quality and safety education into clinical nursing education through a dedicated education unit.

    PubMed

    Masters, Kelli

    2016-03-01

    The Institute of Medicine and American Association of Colleges of Nursing are calling for curriculum redesign that prepares nursing students with the requisite knowledge and skills to provide safe, high quality care. The purpose of this project was to improve nursing students' knowledge of quality and safety by integrating Quality and Safety Education for Nurses into clinical nursing education through development of a dedicated education unit. This model, which pairs nursing students with front-line nursing staff for clinical experiences, was implemented on a medical floor in an acute care hospital. Prior to implementation, nurses and students were educated about the dedicated education unit and quality and safety competencies. During each clinical rotation, students collaborated with their nurses on projects related to these competencies. Students' knowledge was assessed using questions related to quality and safety. Students who participated in the dedicated education unit had higher scores than those with traditional clinical rotations. Focus groups were held mid-semester to assess nurses' perceptions of the experience. Five themes emerged from the qualitative data including thirsting for knowledge, building teamwork and collaboration, establishing trust and decreasing anxiety, mirroring organization and time management skills, and evolving confidence in the nursing role.

  4. HERMES: a soft X-ray beamline dedicated to X-ray microscopy.

    PubMed

    Belkhou, Rachid; Stanescu, Stefan; Swaraj, Sufal; Besson, Adrien; Ledoux, Milena; Hajlaoui, Mahdi; Dalle, Didier

    2015-07-01

    The HERMES beamline (High Efficiency and Resolution beamline dedicated to X-ray Microscopy and Electron Spectroscopy), built at Synchrotron SOLEIL (Saint-Auban, France), is dedicated to soft X-ray microscopy. The beamline combines two complementary microscopy methods: XPEEM (X-ray Photo Emitted Electron Microscopy) and STXM (Scanning Transmission X-ray Microscopy) with an aim to reach spatial resolution below 20 nm and to fully exploit the local spectroscopic capabilities of the two microscopes. The availability of the two methods within the same beamline enables the users to select the appropriate approach to study their specific case in terms of sample environment, spectroscopy methods, probing depth etc. In this paper a general description of the beamline and its design are presented. The performance and specifications of the beamline will be reviewed in detail. Moreover, the article is aiming to demonstrate how the beamline performances have been specifically optimized to fulfill the specific requirements of a soft X-ray microscopy beamline in terms of flux, resolution, beam size etc. Special attention has been dedicated to overcome some limiting and hindering problems that are usually encountered on soft X-ray beamlines such as carbon contamination, thermal stability and spectral purity.

  5. Conceptual design of dedicated road lighting for city park and housing estate.

    PubMed

    Wu, Rengmao; Li, Kan; Liu, Peng; Zheng, Zhenrong; Li, Haifeng; Liu, Xu

    2013-07-20

    We propose dedicated road lighting, which is significantly superior to the existing lighting technologies for the city park and housing estate. This dedicated lighting employs freeform surfaces to effectively control the optical field of the LED source to produce three kinds of illumination modes for the curved road, straight road, and the small public square, respectively, perfectly matching the road conditions of the city park and housing estate. A mathematical model of freeform illumination design is presented to achieve a conceptual design of this road lighting, and a numerical technology for solving this design problem is introduced for the first time, to our knowledge. An illumination model of this conceptual design is constructed. The experimental results of the conceptual design tally closely with the target. This dedicated road lighting, integrated with energy saving, healthy lighting and artistic beauty, provides a beautiful landscape for the city park and the housing estate at night, and will play an important role in improving quality of life of the urban inhabitants.

  6. Insights on co-catalyst-promoted enamine formation between dimethylamine and propanal through ab initio and density functional theory study.

    PubMed

    Patil, Mahendra P; Sunoj, Raghavan B

    2007-10-26

    The mechanistic details on enamine formation between dimethylamine and propanal are unraveled using the ab initio and density functional theory methods. The addition of secondary amine to the electrophile and simultaneous proton transfer results in a carbinolamine intermediate, which subsequently undergoes dehydration to form enamine. The direct addition of amine as well as the dehydration of the resulting carbinolamine intermediate is predicted to possess fairly high activation barrier implying that a unimolecular process is unlikely to be responsible for enamine formation. Different models are therefore proposed which could explain the relative ease of enamine formation under neat condition as well as under the influence of methanol as the co-catalyst. The explicit inclusion of either the reagent or the co-catalyst is considered in the transition states as stabilizing agents. The participation of the reagent or the co-catalyst as a monofunctional ancillary species is found to stabilize the transition states relative to the unassisted or the direct addition/dehydration pathways. The reduction in enthalpy of activation is found to be much more dramatic when two co-catalysts participate in an active bifunctional mode in the rate-determining dehydration step. The transition structures exhibited characteristic features of a relay proton transfer mechanism. The free energy of activation associated with the two methanol-assisted pathway is found to be 16.7 kcal/mol lower than that of the unassisted pathway. The results are found to be in concurrence with the available reports on the rate acceleration by co-catalysts in the Michael reaction between enamine and methyl vinyl ketone under neat conditions.

  7. A novel PPARα agonist propane-2-sulfonic acid octadec-9-enyl-amide inhibits inflammation in THP-1 cells.

    PubMed

    Zhao, Yun; Yan, Lu; Luo, Xiu-Mei; Peng, Lu; Guo, Han; Jing, Zuo; Yang, Li-Chao; Hu, Rong; Wang, Xuan; Huang, Xue-Feng; Wang, Yi-Qing; Jin, Xin

    2016-10-05

    Our group synthesized propane-2-sulfonic acid octadec-9-enyl-amide (N15), a novel peroxisome proliferator activated receptor alpha (PPARα) agonist. Because PPARα activation is associated with inflammation control, we hypothesize that N15 may have anti-inflammatory effects. We investigated the effect of N15 on the regulation of inflammation in THP-1 cells stimulated with lipopolysaccharide (LPS). In particular, we assessed the production of chemokines, adhesion molecules and proinflammatory cytokines, three important types of cytokines that are released from monocytes and are involved in the development of atherosclerosis. The results showed that N15 remarkably reduced the mRNA expression of chemokines, such as monocyte chemotactic protein 1 (MCP-1 or CCL2), interleukin-8 (IL-8) and interferon-inducible protein-10 (IP-10 or CXCL10), and proinflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). N15 also decreased the protein expression of vascular cell adhesion molecule (VCAM) and matrix metalloproteinase (MMP) 2 and 9. The reduction in the expression of cytokine mRNAs observed following N15 treatment was abrogated in THP-1 cells treated with PPARα siRNA, indicating that the anti-inflammatory effects of N15 are dependent on PPARα activation. Toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) and signal transducer and activator of transcription 3 (STAT3) inhibition, which are dependent on PPARα activation, were also involved in the mechanism underlying the anti-inflammatory effects of N15. In conclusion, the novel PPARα agonist, N15, exerts notable anti-inflammatory effects, which are mediated via PPARα activation and TLR4/NF-κB and STAT3 inhibition, in LPS-stimulated THP-1 cells. In our study, N15 exhibits promise for the treatment of atherosclerosis.

  8. Mobilization of mercury and arsenic in humans by sodium 2,3-dimercapto-1-propane sulfonate (DMPS).

    PubMed Central

    Aposhian, H V

    1998-01-01

    Sodium 2,3-dimercapto-1-propane sulfonate (DMPS, Dimaval) is a water-soluble chelating agent that can be given by mouth or systemically and has been used to treat metal intoxication since the 1960s in the former Soviet Union and since 1978 in Germany. To better approximate the body burdens of Hg and As in humans, DMPS-Hg andDMPS-As challenge tests have been developed. The tests involve collecting an overnight urine, administering 300 mg DMPS at zero time, collecting the urine from 0 to 6 hr, and determining the urinary Hg before and after DMPS is given. The challenge test, when applied to normal college student volunteers with and without amalgam restorations in their mouths, indicated that two-thirds of the Hg excreted in the urine after DMPS administration originated in their dental amalgams. In addition, there was a positive linear correlation between the amalgam score (a measure of amalgam surface) and urinary Hg after the challenge test. When the DMPS-Hg challenge test was used to study dental personnel occupationally exposed to Hg, the urinary excretion of Hg was 88, 49, and 35 times greater after DMPS administration than before administration in 10 dental technicians, 5 dentists, and 13 nondental personnel, respectively. DMPS also was used to measure the body burden of humans with a history of drinking water containing 600 microgram As/liter. DMPS administration resulted in a tripling of the monomethylarsonic acid percentage and a halving of the dimethylarsinic acid percentage as related to total urinary As. Because South American animals studied were deficient in arsenite methyltransferase, a hypothesis is presented that arsenite and arsenite methyltransferase may have had a role in the evolution of some South American animals. Images Figure 1 Figure 3 Figure 4 Figure 6 Figure 7 Figure 8 Figure 9 PMID:9703487

  9. Development, modeling, simulation, and testing of a novel propane-fueled Brayton-Gluhareff cycle acoustically-pressurized ramjet engine

    NASA Astrophysics Data System (ADS)

    Bramlette, Richard B.

    In the 1950s, Eugene Gluhareff built the first working "pressure jet" engine, a variation on the classical ramjet engine with a pressurized inlet system relying on sonic tuning which allowed operation at subsonic speeds. The engine was an unqualified success. Unfortunately, after decades of sales and research, Gluhareff passed away leaving behind no significant published studies of the engine or detailed analysis of its operation. The design was at serious risk of being lost to history. This dissertation is intended to address that risk by studying a novel subscale modification of Gluhareff's original design operating on the same principles. Included is a background of related engine and how the pressure jet is distinct. The preliminary sizing of a pressure jet using closed-form expressions is then discussed followed by a review of propane oxidation modeling, how it integrates into the Computational Fluid Dynamics (CFD) solver, and the modeling of the pressure jet engine cycle with CFD. The simulation was matched to experimental data recorded on a purpose-built test stand recording chamber pressure, exhaust speed (via a Pitot/static system), temperatures, and thrust force. The engine CFD simulation produced a wide range of qualitative results that matched the experimental data well and suggested strong recirculation flows through the engine confirming suspicions about how the engine operates. Engine operating frequency between CFD and experiment also showed good agreement and appeared to be driven by the "Kadenacy Effect." The research effort lastly opens the door for further study of the engine cycle, the use of pressurized intakes to produce static thrust in a ramjet engine, the Gluhareff pressure jet's original geometry, and a wide array of potential applications. A roadmap of further study and applications is detailed including a modeling and testing of larger engines.

  10. Intelligent Urban Public Transportation for Accessibility Dedicated to People with Disabilities

    PubMed Central

    Zhou, Haiying; Hou, Kun-Mean; Zuo, Decheng; Li, Jian

    2012-01-01

    The traditional urban public transport system generally cannot provide an effective access service for people with disabilities, especially for disabled, wheelchair and blind (DWB) passengers. In this paper, based on advanced information & communication technologies (ICT) and green technologies (GT) concepts, a dedicated public urban transportation service access system named Mobi+ has been introduced, which facilitates the mobility of DWB passengers. The Mobi+ project consists of three subsystems: a wireless communication subsystem, which provides the data exchange and network connection services between buses and stations in the complex urban environments; the bus subsystem, which provides the DWB class detection & bus arrival notification services; and the station subsystem, which implements the urban environmental surveillance & bus auxiliary access services. The Mobi+ card that supports multi-microcontroller multi-transceiver adopts the fault-tolerant component-based hardware architecture, in which the dedicated embedded system software, i.e., operating system micro-kernel and wireless protocol, has been integrated. The dedicated Mobi+ embedded system provides the fault-tolerant resource awareness communication and scheduling mechanism to ensure the reliability in data exchange and service provision. At present, the Mobi+ system has been implemented on the buses and stations of line ‘2’ in the city of Clermont-Ferrand (France). The experiential results show that, on one hand the Mobi+ prototype system reaches the design expectations and provides an effective urban bus access service for people with disabilities; on the other hand the Mobi+ system is easily to deploy in the buses and at bus stations thanks to its low energy consumption and small form factor. PMID:23112622

  11. Intelligent urban public transportation for accessibility dedicated to people with disabilities.

    PubMed

    Zhou, Haiying; Hou, Kun-Mean; Zuo, Decheng; Li, Jian

    2012-01-01

    The traditional urban public transport system generally cannot provide an effective access service for people with disabilities, especially for disabled, wheelchair and blind (DWB) passengers. In this paper, based on advanced information & communication technologies (ICT) and green technologies (GT) concepts, a dedicated public urban transportation service access system named Mobi+ has been introduced, which facilitates the mobility of DWB passengers. The Mobi+ project consists of three subsystems: a wireless communication subsystem, which provides the data exchange and network connection services between buses and stations in the complex urban environments; the bus subsystem, which provides the DWB class detection & bus arrival notification services; and the station subsystem, which implements the urban environmental surveillance & bus auxiliary access services. The Mobi+ card that supports multi-microcontroller multi-transceiver adopts the fault-tolerant component-based hardware architecture, in which the dedicated embedded system software, i.e., operating system micro-kernel and wireless protocol, has been integrated. The dedicated Mobi+ embedded system provides the fault-tolerant resource awareness communication and scheduling mechanism to ensure the reliability in data exchange and service provision. At present, the Mobi+ system has been implemented on the buses and stations of line '2' in the city of Clermont-Ferrand (France). The experiential results show that, on one hand the Mobi+ prototype system reaches the design expectations and provides an effective urban bus access service for people with disabilities; on the other hand the Mobi+ system is easily to deploy in the buses and at bus stations thanks to its low energy consumption and small form factor.

  12. GammaPod—A new device dedicated for stereotactic radiotherapy of breast cancer

    PubMed Central

    Yu, Cedric X.; Shao, Xinyu; Zhang, Jin; Regine, William; Zheng, Mike; Yu, Ying S.; Deng, Jianchun; Duan, Zhengcheng

    2013-01-01

    Purpose: This paper introduces a new external beam radiotherapy device named GammaPod that is dedicated for stereotactic radiotherapy of breast cancer. Methods: The design goal of the GammaPod as a dedicated system for treating breast cancer is the ability to deliver ablative doses with sharp gradients under stereotactic image guidance. Stereotactic localization of the breast is achieved by a vacuum-assisted breast immobilization cup with built-in stereotactic frame. Highly focused radiation is achieved at the isocenter due to the cross-firing from 36 radiation arcs generated by rotating 36 individual Cobalt-60 beams. The dedicated treatment planning system optimizes an optimal path of the focal spot using an optimization algorithm borrowed from computational geometry such that the target can be covered by 90%–95% of the prescription dose and the doses to surrounding tissues are minimized. The treatment plan is intended to be delivered with continuous motion of the treatment couch. In this paper the authors described in detail the gamma radiation unit, stereotactic localization of the breast, and the treatment planning system of the GammaPod system. Results: A prototype GammaPod system was installed at University of Maryland Medical Center and has gone through a thorough functional, geometric, and dosimetric testing. The mechanical and functional performances of the system all meet the functional specifications. Conclusions: An image-guided breast stereotactic radiotherapy device, named GammaPod, has been developed to deliver highly focused and localized doses to a target in the breast under stereotactic image guidance. It is envisioned that the GammaPod technology has the potential to significantly shorten radiation treatments and even eliminate surgery by ablating the tumor and sterilizing the tumor bed simultaneously. PMID:23635251

  13. Universal precautions and dedicated machines as cheap and effective measures to control HCV spread.

    PubMed

    Cerrai, T; Michelassi, S; Ierpi, C; Toti, G; Zignego, A L; Lombardi, M

    1998-01-01

    Haemodialysis patients are at great risk for HCV infection, and a strict relationship is clear between anti-HCV positivity and dialysis age or hospital dialysis, irrespective of previous blood transfusions. Notwithstanding that, the precise root of its nosocomial nontransfusional diffusion among haemodialysis patients is not clear yet. As isolation is a very expensive policy, we evaluated whether simpler measures such as the observance of the Universal Precautions (UP), and the use of anti-HCV positive patient dedicated monitors can stop the diffusion of HCV infection in a hospital haemodialysis centre. Since January 1990 to December 1991 (1st phase), the patients shared the monitors irrespective of their serological status for HCV, and training of the dialysis care staff was not performed with regard to the UP. Since January 1991 to June 1996 (2nd phase), according to the UP, strictly personal dialysis-tools were used for all patients, anti-HCV positive patients were assigned to dedicated monitors in defined (not separated) areas of the dialysis rooms and the dialysis care staff was trained to the strict observance of the UP. In the first phase of the follow-up 5 seroconversions occurred; none occurred in the second one. Our study shows that isolation is not required for such patients. We believe that measures such as the application of UP, dedicated machines and continuous training of the care staff, instead of the isolation of positive patients, result in the same efficacy and are cheaper than isolation of positive patients. Therefore they are mandatory for all haemodialysis centres.

  14. Development and implementation of a dedicated postoperative evaluation service to improve compliance of postoperative visits

    PubMed Central

    Vacanti, Joshua Charles; Urman, Richard Dennis; Sarin, Pankaj; Liu, Xiaoxia; Kodali, Bhavani Shankar

    2015-01-01

    Background and Aims: Postoperative patient evaluation is an integral component of perioperative care. An audit of our anesthesia department's records demonstrated a compliance rate of <50%. We postulated that the development of clinical anesthesia service dedicated to performing such evaluations would improve compliance significantly. Materials and Methods: This retrospective study examined postoperative follow-up completion rate at a large academic center. Data were collected from 58,000 anesthetics during three periods, between each of which an intervention was introduced. The first period examined completion rate when postoperative evaluations were left to the team performing the anesthetic. During the second period, this task was delegated to groups of anesthesiologists based on surgical subspecialty; these smaller groups utilized rotating residents. The third period examined completion rate after implementation of a postoperative evaluation service. All periods utilized the department's electronics database to identify operative patients. The number of adverse anesthesia events reported was also recorded. Results: A significant difference in the proportions of compliance with postoperative evaluations among all three periods was detected. Compliance was 47% during period one and improved to 66% during period two. During period three, which employed a postoperative evaluation service, compliance was 83%. The number of adverse events reported per month increased significantly following the first study period from 95 reported monthly events to 215 and 201 in the second and third periods, respectively. Conclusion: By creating a dedicated postoperative evaluation service using available technology, we improved postoperative evaluation completion rate from 47% to 83%, and demonstrated a significant increase in the number of adverse events reported. Based on this, we support the deployment of a dedicated service as a quality improvement initiative. PMID:25788778

  15. Demonstration of the importance of a dedicated neutron beam monitoring system for BNCT facility.

    PubMed

    Chao, Der-Sheng; Liu, Yuan-Hao; Jiang, Shiang-Huei

    2016-01-01

    The neutron beam monitoring system is indispensable to BNCT facility in order to achieve an accurate patient dose delivery. The neutron beam monitoring of a reactor-based BNCT (RB-BNCT) facility can be implemented through the instrumentation and control system of a reactor provided that the reactor power level remains constant during reactor operation. However, since the neutron flux in reactor core is highly correlative to complicated reactor kinetics resulting from such as fuel depletion, poison production, and control blade movement, some extent of variation may occur in the spatial distribution of neutron flux in reactor core. Therefore, a dedicated neutron beam monitoring system is needed to be installed in the vicinity of the beam path close to the beam exit of the RB-BNCT facility, where it can measure the BNCT beam intensity as closely as possible and be free from the influence of the objects present around the beam exit. In this study, in order to demonstrate the importance of a dedicated BNCT neutron beam monitoring system, the signals originating from the two in-core neutron detectors installed at THOR were extracted and compared with the three dedicated neutron beam monitors of the THOR BNCT facility. The correlation of the readings between the in-core neutron detectors and the BNCT neutron beam monitors was established to evaluate the improvable quality of the beam intensity measurement inferred by the in-core neutron detectors. In 29 sampled intervals within 16 days of measurement, the fluctuations in the mean value of the normalized ratios between readings of the three BNCT neutron beam monitors lay within 0.2%. However, the normalized ratios of readings of the two in-core neutron detectors to one of the BNCT neutron beam monitors show great fluctuations of 5.9% and 17.5%, respectively.

  16. GammaPod-A new device dedicated for stereotactic radiotherapy of breast cancer

    SciTech Connect

    Yu, Cedric X.; Shao Xinyu; Deng Jianchun; Duan Zhengcheng; Zhang Jin; Zheng, Mike; Yu, Ying S.; Regine, William

    2013-05-15

    Purpose: This paper introduces a new external beam radiotherapy device named GammaPod that is dedicated for stereotactic radiotherapy of breast cancer. Methods: The design goal of the GammaPod as a dedicated system for treating breast cancer is the ability to deliver ablative doses with sharp gradients under stereotactic image guidance. Stereotactic localization of the breast is achieved by a vacuum-assisted breast immobilization cup with built-in stereotactic frame. Highly focused radiation is achieved at the isocenter due to the cross-firing from 36 radiation arcs generated by rotating 36 individual Cobalt-60 beams. The dedicated treatment planning system optimizes an optimal path of the focal spot using an optimization algorithm borrowed from computational geometry such that the target can be covered by 90%-95% of the prescription dose and the doses to surrounding tissues are minimized. The treatment plan is intended to be delivered with continuous motion of the treatment couch. In this paper the authors described in detail the gamma radiation unit, stereotactic localization of the breast, and the treatment planning system of the GammaPod system. Results: A prototype GammaPod system was installed at University of Maryland Medical Center and has gone through a thorough functional, geometric, and dosimetric testing. The mechanical and functional performances of the system all meet the functional specifications. Conclusions: An image-guided breast stereotactic radiotherapy device, named GammaPod, has been developed to deliver highly focused and localized doses to a target in the breast under stereotactic image guidance. It is envisioned that the GammaPod technology has the potential to significantly shorten radiation treatments and even eliminate surgery by ablating the tumor and sterilizing the tumor bed simultaneously.

  17. Strengthening moral reasoning through dedicated ethics training in dietetic preparatory programs.

    PubMed

    Hewko, Sarah J; Cooper, Sarah L; Cummings, Greta G

    2015-01-01

    Moral reasoning skills, associated with the ability to make ethical decisions effectively, must be purposively fostered. Among health professionals, enhanced moral reasoning is linked to superior clinical performance. Research demonstrates that moral reasoning is enhanced through dedicated, discussion-based ethics education offered over a period of 3-12 weeks. Current dietetic students and practicing dietitians seeking to strengthen their moral reasoning skills can undertake elective ethics education. Further research within dietetic preparatory programs is warranted to better inform the development and implementation of ethics courses.

  18. ESF GROUND SUPPORT - MATERIAL DEDICATION ANALYSIS FOR STRUCTURAL STEEL AND ACCESSORIES FROM A COMMERCIAL GRADE SOURCE

    SciTech Connect

    M.D. Stine

    1996-01-23

    The purpose of this analysis is to select the critical characteristics to be verified for steel sets and accessories and the verification methods to be implemented through a material dedication process for the procurement and use of commercial grade structural steel sets and accessories (which have a nuclear safety function) to be used in ground support (with the exception of alcove ground support and alcove opening framing, which are not addressed in this analysis) for the Exploratory Studies Facility (ESF) Topopah Spring (TS) Loop. The ESF TS Loop includes the North Ramp, Main Drift, and South Ramp underground openings.

  19. Building a dedicated information barrier system for warhead and sensitive item verification

    SciTech Connect

    ZUHOSKI,P.B.; INDUSI,J.P.; VANIER,P.E.

    1999-07-25

    This paper documents the development of a dedicated information barrier system for warhead and sensitive item verification. The system the authors describe includes software and hardware information barriers used in conjunction with suitable procedures (or protocols) to achieve a high quality verification while minimizing intrusiveness and preventing transfer of sensitive data to inspectors. The system they describe has been referred to as CIVET--Controlled Intrusiveness Verification Technology and has been implemented to verify warheads and warhead components during various exercises and demonstrations under the auspices of the Department of Energy (DOE) and the Department of Defense (DOD).

  20. Proposal for a Dedicated Collider at the Fermi National Accelerator Laboratory May, 1983

    SciTech Connect

    None, None

    1983-05-01

    This document describes a proposal for a proton-antiproton/ electron-proton Dedicated Collider facility at Fermilab, to be built between 1985 and 1989. The center-of-mass energy of the pp collider is more than 4 TeV and the (Stage I) ep facility provides collisions of a 10 GeV electron beam on the 2-TeV proton beam (s = 80000 GeV2). An increase of the electron energy to 40 GeV is a natural second-stage project for a later date.