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Sample records for dedicated propane chrysler

  1. Chrysler`s hybrid concept

    SciTech Connect

    Jost, K.

    1996-05-01

    The ten-year Partnership for a New Generation of Vehicles (PNGV), initiated in September 1993 by Chrysler, Ford, General Motors, and the US federal government, established three goals. The long-term goal of the program is the breakthrough vehicle referred to by some as the supercar or clean car that gets about 80 mpg, without sacrificing the average attributes of current vehicles such as the Chrysler Concorde, Ford Taurus, and Chevrolet Lumina. To achieve this long-term goal, the partnership realized that a manufacturing infrastructure had to be developed to attain cost and production levels consistent with auto industry norms; that is the objective of the initial goal, the advanced manufacturing phase. An interim goal tries to spin off as much of the advanced technology as possible to Big Three conventional vehicles so that they can benefit from advancements in mass reduction, aerodynamics, and materials technologies. PNGV`s lead government agency is the Department of Commerce, with the Department of Energy being a major resource. Intellectual input for the program is provided, on the government side, by the NSF, DoD, and NASA. Each of the Big 3 has contracts funded by the Department of Energy in many technology areas, and the companies are sharing knowledge to avoid duplication of effort.

  2. Propane poisoning

    MedlinePlus

    Propane is a colorless and odorless flammable gas that can turn into liquid under very cold temperatures. This article discusses the harmful effects from breathing in or swallowing propane. Breathing in or swallowing propane can be ...

  3. 78 FR 55077 - Timonium Chrysler, Inc. d/b/a Don White's Timonium Chrysler Jeep Dodge; Analysis of Proposed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-09

    ... From the Federal Register Online via the Government Publishing Office FEDERAL TRADE COMMISSION Timonium Chrysler, Inc. d/b/a Don White's Timonium Chrysler Jeep Dodge; Analysis of Proposed Consent Order... Timonium Chrysler, Inc. d/b/a Don White's Timonium Chrysler Jeep Dodge. The proposed consent order has...

  4. 75 FR 20389 - Chrysler Group LLC, Formerly Known as Chrysler LLC, Warren Office Building, Including On-Site...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-19

    ... Employment and Training Administration Chrysler Group LLC, Formerly Known as Chrysler LLC, Warren Office Building, Including On-Site Leased Workers from Product Action International, LLC, Warren, Michigan... applicable to workers of Chrysler Group LLC, formerly known as Chrysler LLC, Warren Office Building,...

  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. Propane fear

    SciTech Connect

    Begley, R.

    1992-02-12

    A minor feature of a Congressional energy bill is causing consternation for a number of propane-consuming chemical companies. The firms are fighting the bill`s inclusion of liquefied petroleum gas (LPG) on a list of alternative fuels that can be used to meet its urban fleet vehicles requirements. The firms fear that this added use would drive up the price of propane-an LPG-for homeowners, farmers, and themselves. Speaking for the Propane Consumers Coalition, a Dow Chemical spokesman says 7.7 million households use propane, as does agriculture, and current demand is such that December saw a 23-year low in US inventories. The US depends on imports of propane, he says, and about half the propane sold in the US is derived from the refining of oil, much of which is also imported. Adding demand for vehicle fuel would drive up imports and process, the spokesman says, thereby damaging all users, including the petrochemical industry.

  8. 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.

  9. 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

  10. 75 FR 11916 - Chrysler Transportation LLC, a Subsidiary of Chrysler LLC, Including On-Site Leased Workers from...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ..., Detroit, Michigan. The notice was published in the Federal Register on January 14, 2009 (74 FR 2136). At... subject firm. The workers provide transport of parts from suppliers to Chrysler manufacturing facilities... assembly of automotive vehicles. New information shows that workers leased from Caravan Knight...

  11. 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

  12. Auto propane -- Some technical considerations

    SciTech Connect

    1998-12-31

    This booklet reviews some of the facts about propane as a vehicle fuel. It describes propane fuel properties, propane vehicle fuel systems and their components, propane vehicles and engines obtainable as original equipment from the vehicle manufacturer, after-market propane fuel system installations, propane vehicle operational characteristics, propane-fueled vehicle maintenance, government regulations and safety measures related to propane vehicles, and the environmental benefits of propane and propane-fueled vehicles. The final sections discuss the economics of propane vehicle ownership and the factors to be considered when estimating annual or lifetime savings or payback periods. Appendices include a directory of information sources, a sample worksheet for calculating payback, and examples of success stories relating the positive experiences of vehicle fleets with propane fueling.

  13. 75 FR 38126 - UAW-Chrysler National Training Center, Detroit, MI; Notice of Affirmative Determination Regarding...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ... of determination was published in the Federal Register on May 20, 2010 (75 FR 28301). The initial... Employment and Training Administration UAW-Chrysler National Training Center, Detroit, MI; Notice of... of the workers in the UAW-Chrysler National Training Center, Detroit, Michigan, had not...

  14. 75 FR 53375 - Petition for Exemption From the Federal Motor Vehicle Theft Prevention Standard; Chrysler

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    .... Deborah Mazyck, International Policy, Fuel Economy and Consumer Programs, NHTSA, W43-443, 1200 New Jersey... location of the components of the antitheft device for the new vehicle line. Chrysler will install the... vehicle to start and continue to run. Chrysler stated that the Sentry Key Immobilizer Module (SKIM),...

  15. 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.

  16. 77 FR 8944 - Chrysler Group, LLC, Receipt of Petition for Decision of Inconsequential Noncompliance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ... published on April 11, 2000, (65 FR 19477-78). The petition, supporting materials, and all comments received...,536 kilograms (10,000 pounds) or less. Chrysler has filed an appropriate report dated May 3,...

  17. 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)

  18. 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

  19. 78 FR 53500 - Petition for Exemption From the Federal Motor Vehicle Theft Prevention Standard; Chrysler

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-29

    ...- marking requirements beginning with MY 2004 (67 FR 79687, December 30, 2002). Chrysler further asserts.... The RFHM contains a Radio Frequency (RF) transceiver and a microprocessor and it initiates the ignition process by communicating with the BCM through SKIS. The microprocessor-based SKIS hardware...

  20. 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... July 1, 2010 (75 FR 38142). Pursuant to 29 CFR 90.18(c), reconsideration may be granted under...

  1. 76 FR 68260 - Petition for Exemption From the Federal Motor Vehicle Theft Prevention Standard; Chrysler

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-03

    ..., design, and location of the components of the antitheft device for the vehicle line. Chrysler will... microprocessor and serves as the Remote Keyless Entry RF receiver. The RFHM also acts as a receiver if the... 95 percent reliability with 90 percent confidence. In addition to the design and...

  2. 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

    ... CFR 2570, Subpart B (55 FR 32836, August 10, 1990). Effective December 31, 1978, section 102 of Reorganization Plan No. 4 of 1978, (43 FR 47713, October 17, 1978) transferred the authority of the Secretary of... Individual Exemption Involving Chrysler LLC, Located in Auburn Hills, MI, 74 FR 51182 (October 5,...

  3. 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

    ... LLC, (Chrysler) petition for exemption of the Jeep Patriot vehicle line in accordance with 49 CFR Part... determined that the antitheft device to be placed on the line as standard equipment is likely to be as... Jeep Patriot vehicle line, beginning with MY 2011. The petition requested an exemption from...

  4. 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

    ... 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 Affirmative... in the Federal Register on August 6, 2010 (75 FR 47635). The initial investigation resulted in...

  5. 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.

  6. Propane gas: Handle with care

    SciTech Connect

    Fernald, D.

    1996-04-01

    Because of its chemical composition and combustion properties, this liquefied petroleum (LP) gas can be mixed with air and used as a direct replacement for natural gas with no burner or process equipment modifications. One major and growing use of propane is as a vehicle fuel. Growing industrial use of propane also has prompted the National Fire Protection Association (NFPA) to issue new codes. NFPA standard 58-95, Storing and Handling of Liquefied Petroleum Gases, stresses the need to adhere to safe work and handling practices whenever propane is involved. All employees directly handling the gas should be formally trained and certified, and recertified annually. Although the code applies only to those directly handling propane or operating propane equipment such as portable cylinder filling stations, all employees working around or with propane or other LP gases should understand the characteristics of LP gas and be aware of basic safe handling practices. The paper discusses what LP gas is, special safety concerns, the care required in refilling cylinders, and cylinder inspection.

  7. Propane-Fueled Jet Engine

    NASA Astrophysics Data System (ADS)

    Farwell, D. A.; Svenson, A. J.; Ramsier, R. D.

    2001-04-01

    We present our recent efforts to design, construct, and test a gas turbine, or jet, engine. Our design utilizes a turbocharger and ignition system from an automobile, and a flame tube/reaction chamber unit fabricated by hand from stainless steel. Once the engine is running, it is completely self-sustaining as long as there is a fuel supply, which in our case is propane. Air is forced into the intake where it is compressed and then injected into the combustion chamber where it is mixed with propane. The spark plugs ignite the air-propane mixture which burns to produce thrust at the exhaust. We have performed operational tests under different environmental conditions and with several turbochargers. We are currently working on adding a lubrication system to the engine, and will discuss our plan to experiment with the reaction chamber and flame tube design in an effort to improve performance and efficiency. *Corresponding author: rex@uakron.edu

  8. 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.

  9. 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.

  10. 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.

  11. 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

    ... International Trade Administration Effect on Propane Consumers of the Propane Education and Research Council's... comment on whether the operation of the Propane Education and Research Council (PERC), in conjunction with..., agricultural, process and nonfuel users of propane. This notice of inquiry is part of an effort to...

  12. Catalysis of propane oxidation and premixed propane-air flames

    NASA Astrophysics Data System (ADS)

    Wiswall, James T.

    Improvements in deriving energy from hydrocarbon fuels will have a large impact on our efforts to transition to sustainable and renewable energy resources. The hypothesis for this work is that catalysis can extend the useful operating conditions for hydrocarbon oxidation and combustion, improve device efficiencies, and reduce pollutants. Catalysis of propane oxidation and premixed propane-air flames are examined experimentally, using a stagnation-flow reactor to identify the important physical and chemical mechanisms over a range of flow catalyst, and temperature conditions. The propane oxidation studies consider five catalyst materials: platinum, palladium, SnO2, 90% SnO2 -- 10% Pt (by mass), and quartz. The volume fractions of CO2, O2, C 3H8, CO, NO and the electric power required to control the catalyst temperature quantify the activity of each catalyst for the equivalence ratios of φ = 0.67, 1.00, and 1.50, and over the catalyst temperature range 23-800°C. Quartz is used as a baseline and confirmed to be non-reactive at all conditions. 100% SnO2 has minimal reactivity. Platinum, palladium, and 90% SnO2 -- 10% Pt show similar trends and have the highest catalytic activity at φ = 1.50. Palladium and 90% SnO 2 -- 10% Pt show an increasing catalyst-activation temperature (Tsa) for decreasing φ, and platinum shows an approximately constant catalyst-activation temperature for decreasing φ (Tsa = 310°C). Of these the 90% SnO2 -- 10% Pt catalyst shows the lowest Tsa, occurring for the φ = 1.5 mixture (Tsa = 250°C). The studies of premixed propane-air flames consider platinum and quartz stagnation surfaces for fuel-mixture velocities from 0.6-1.6 m/s. Five flame structures are observed: cool core envelope, cone, envelope, disk and ring flames. The lean-extinction limit, disk-to-ring flame transition φ, and the disk-flame to stagnation-plane distance are reported. Platinum inhibits the ring flame structure. The lean-extinction limit and disk-flame to stagnation

  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. 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.

  16. Newell library dedicated

    NASA Astrophysics Data System (ADS)

    Richman, Barbara T.

    On September 27 the library at the Goddard Space Flight Center in Green belt, Md., was renamed the Homer E. Newell Library in memory of the man who was once the National Aeronautics and Space Administration's (NASA) deputy director for space flight programs, director of the Office of Space Sciences, and associate administrator. Newell, who was 68 years old when he died on July 18, 1983, was president of AGU from 1970 to 1972.A photograph of Newell and a plaque will be permanently displayed in the library. The plaque, which will be framed in walnut, reads, “The Homer E. Newell Library, dedicated September 27, 1983, to honor his leadership and contributions to America's space science program.” NASA Administrator James M. Beggs and Mrs. Homer E. Newell were scheduled to participate in the dedication ceremonies.

  17. Health-hazard evaluation report GHETA 83-309-1405, Chrysler Corporation Foundry, Indianapolis, Indiana

    SciTech Connect

    Patil, A.

    1984-01-01

    In response to a request arising out of employee concerns over the medical surveillance program at the Chrysler Corporation Foundry located in Indianapolis, Indiana, an evaluation was made of chest radiographs evaluated by the program with specific concern directed to disagreement on the radiographic diagnosis of pneumoconiosis. The request was made by the Chrysler Corporation and the United Auto Workers National Joint Committee on Health and Safety. Three NIOSH certified B-readers independently interpreted a set of 78 systematically sampled posteroanterior (PA) chest radiographs from the system files. These interpretations were compared among themselves and with company interpretations. While none of the radiographs was deemed unreadable, 35% were classified as having poor technical quality. Only one film was found which had a profusion of small opacities, and the company had interpreted the film as positive. Overall, agreement on proportion of positive readings and agreement on individual films was as good between the company and B-readers as it was between any two of the individual B-readers. The author recommends, however, that in order to avoid future complaints of the nature, the company should use standard radiographic equipment and techniques, NIOSH certified B-readers, and current international classifications of radiographs for pneumoconioses in their medical surveillance program.

  18. 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

    ... FR 28301). The Department's Notice of Affirmative Determination Regarding Application for Reconsideration was signed on June 21, 2010, and was published in the Federal Register on July 1, 2010 (75 FR... Employment and Training Administration UAW-Chrysler National Training Center Technology Training...

  19. 75 FR 52981 - Chrysler, LLC, Detroit Axle Plant, Including On-Site Leased Workers from Caravan Knight...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-30

    ... was published in the Federal Register on February 2, 2009 (74 FR 5870). The notice was amended on... notice was published in the Federal Register on March 12, 2010 (75 FR 111914). At the request of a... Employment and Training Administration Chrysler, LLC, Detroit Axle Plant, Including On-Site Leased...

  20. 75 FR 11914 - Chrysler, LLC, Detroit Axle Plant, Including On-Site Leased Workers From Caravan Knight...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... the Federal Register on February 2, 2009 (74 FR 5870). At the request of the State agency, the... Employment and Training Administration Chrysler, LLC, Detroit Axle Plant, Including On-Site Leased Workers From Caravan Knight Facilities Management LLC; Detroit, MI; Amended Certification Regarding...

  1. 75 FR 11914 - Chrysler, LLC, Mack Avenue Engine Plants 1 & 2, Power Train Division, Including On-Site Leased...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... Division, Detroit, Michigan. The notice was published in the Federal Register on December 18, 2008 (73 FR..., Including On-Site Leased Workers From Caravan Knight Facilities Management LLC; Detroit, MI; Amended... Management LLC were employed on-site at the Detroit, Michigan location of Chrysler, LLC, Mack Avenue...

  2. 75 FR 11913 - Chrysler, LLC; Warren Stamping Plant, Including On-Site Leased Workers From Caravan Knight...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... the Federal Register on August 21, 2008 (73 FR 49492). At the request of the State agency, the... Employment and Training Administration Chrysler, LLC; Warren Stamping Plant, Including On-Site Leased Workers From Caravan Knight Facilities Management LLC; Warren, MI; Amended Certification Regarding...

  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. 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

  5. Anaerobic propane oxidation in marine hydrocarbon seep sediments

    NASA Astrophysics Data System (ADS)

    Quistad, Steven D.; Valentine, David L.

    2011-04-01

    Propane (C 3H 8) is an abundant hydrocarbon in subsurface reservoirs with significance to atmospheric chemistry and to marine biogeochemistry. The anaerobic oxidation of propane coupled to sulfate reduction may prevent sub-seafloor accumulations of propane from entering the ocean and atmosphere. Anaerobic oxidation of propane has recently been demonstrated in cultures of novel sulfate-reducing bacteria, but has not been directly demonstrated or quantified in nature. In this work we describe a method involving incubation with 13C-propane to quantify rates of anaerobic oxidation of propane in anoxic sediment, and we conclusively demonstrate the oxidation of propane under sulfidic conditions in fresh sediments of a marine hydrocarbon seep. Observed rates of anaerobic oxidation of propane adhere to first-order kinetic behavior, enabling the modification of this method for whole core rate determinations. Whole core rates in nine cores from two hydrocarbon seeps measured 0.04-2100 nmoles C 3H 8 cm -3 day -1 by this method. The seep persistently supplied with more propane displayed substantially higher rates of anaerobic oxidation of propane, by 1-2 orders of magnitude when averaged over the top 10-cm, suggesting the development of the microbial community is strongly modulated by the availability of propane. This work is the first to estimate rates for anaerobic oxidation of propane in any environment, and demonstrates the potential importance of the process as a filter for preventing propane from entering the ocean and atmosphere.

  6. No. 2 heating oil/propane program

    SciTech Connect

    McBrien, J.

    1991-06-01

    During the 1990/91 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 1990 through March 1991. This final report begins with an overview of the unique events which had an impact on the reporting period. Next, the report summarizes the results from the residential heating oil and propane price surveys conducted by DOER over the 1990/91 heating season. The report also incorporates the wholesale heating oil and propane prices and inventories collected by the EIA and distributed to the states.

  7. Propane Clathrate Hydrate Formation Accelerated by Methanol.

    PubMed

    Amtawong, Jaruwan; Guo, Jin; Hale, Jared S; Sengupta, Suvrajit; Fleischer, Everly B; Martin, Rachel W; Janda, Kenneth C

    2016-07-01

    The role of methanol as both an inhibitor and a catalyst for the formation of clathrate hydrates (CHs) has been a topic of intense study. We report a new quantitative study of the kinetics of propane CH formation at 253 K from the reaction of propane gas with <75 μm ice particles that have been doped with varying amounts of methanol. We find that methanol significantly accelerates the formation reaction with quite small doping quantities. Even for only 1 methanol molecule per 10 000 water molecules, the maximum uptake rate of propane into CHs is enhanced and the initiation pressure is reduced. These results enable more efficient production of CHs for gas storage. This remarkable acceleration of the CH formation reaction by small quantities of methanol may place constraints on the mechanism of the inhibition effect observed under other conditions, usually employing much larger quantities of methanol. PMID:27275862

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. . . . 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)

  1. 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.

  2. 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.

  3. Titan's prolific propane: The Cassini CIRS perspective

    NASA Astrophysics Data System (ADS)

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

    2009-11-01

    Although propane gas ( C3H8) was first detected in the stratosphere of Titan by the Voyager IRIS infrared spectrometer in 1980, obtaining an accurate measurement of its abundance has proved difficult. All existing measurements have been made by modeling the ν26 band at 748cm-1: however, different analyzes over time have yielded quite different results, and it also suffers from confusion with the strong nearby ν5 band of acetylene. In this paper we select large spectral averages of data from the Cassini Composite Infrared Spectrometer (CIRS) obtained in limb-viewing mode at low latitudes (30 ∘S-30 ∘N), greatly increasing the path length and hence signal-to-noise ratio for optically thin trace species such as propane. By modeling and subtracting the emissions of other gas species, we demonstrate that at least six infrared bands of propane are detected by CIRS, including two not previously identified in Titan spectra. Using a new linelist for the range 1300-1400 cm-1, along with an existing GEISA list, we retrieve propane abundances from two bands at 748 and 1376 cm-1. At 748 cm-1 we retrieve 4.2±0.5×10-7 ( 1-σ error) at 2 mbar, in good agreement with previous studies, although lack of hotbands in the present spectral atlas remains a problem. We also determine 5.7±0.8×10-7 at 2 mbar from the 1376 cm-1 band - a value that is probably affected by systematic errors including continuum gradients due to haze and also an imperfect model of the ν6 band of ethane. This study clearly shows for the first time the ubiquity of propane's emission bands across the thermal infrared spectrum of Titan, and points to an urgent need for further laboratory spectroscopy work, both to provide the line positions and intensities needed to model these bands, and also to further characterize haze spectral opacity. The present lack of accurate modeling capability for propane is an impediment not only for the measurement of propane itself, but also for the search for the emissions of

  4. Dedication

    NASA Technical Reports Server (NTRS)

    Holm, Jeanne M.

    2003-01-01

    The NASA Web portal was exactly what we felt that NASA management wanted: a new face for the Agency., engaging, interactive, and upbeat; a real change from the staid, informational Web site that NASA had already.

  5. Scalable cloud without dedicated storage

    NASA Astrophysics Data System (ADS)

    Batkovich, D. V.; Kompaniets, M. V.; Zarochentsev, A. K.

    2015-05-01

    We present a prototype of a scalable computing cloud. It is intended to be deployed on the basis of a cluster without the separate dedicated storage. The dedicated storage is replaced by the distributed software storage. In addition, all cluster nodes are used both as computing nodes and as storage nodes. This solution increases utilization of the cluster resources as well as improves fault tolerance and performance of the distributed storage. Another advantage of this solution is high scalability with a relatively low initial and maintenance cost. The solution is built on the basis of the open source components like OpenStack, CEPH, etc.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. The Chrysler-Weldtech Approach to Retraining Displaced Workers. A Model Project to Develop Specialized Welding Skills Required for Modern Auto Assembly Operations. Final Technical Report.

    ERIC Educational Resources Information Center

    Lyons, Thomas M.; Knight, Glen A.

    A model project was conducted to demonstrate how Chrysler, in partnership with the education community and the government, could provide technical training to enable displaced workers to contribute to the "H-Body" car launch, to improve their job skills, and to enhance their future employability. The training was conducted on a pilot basis for 2…

  11. Radiolytic oxidation of propane. [Gamma radiation

    SciTech Connect

    Gupta, A.K.

    1983-01-01

    The Co-60 ..gamma.. radiolysis of gaseous propane was studied at 100 torr pressure and 25/sup 0/C, both pure and with 10% added oxygen. In the unscavenged system the major products and their G-values were hydrogen, 4.99; methane, 1.30; ethane, 1.95; iso-butane, 0.61; n-butane, 0.25; i-pentane, 0.42; n-pentane, 0.14; and hexanes, 0.89. Minor products were heptanes, 0.082; octanes, 0.067; nonanes, 0.088, and decanes, 0.033. Small yields of ethylene and propylene were also observed. Yields in the presence of 10% added oxygen were hydrogen, 1.87; methane, 0.83; and ethane, 1.22. Higher saturated hydrocarbons were eliminated. The reaction scheme for formation of major products was examined using computer modeling based on 24 reactions in the unscavenged system and 28 reactions in the propane-oxygen system. Yields could be brought into agreement with the data within experimental error in nearly all cases, but in the pure propane system it was necessary to assume that the molecular hydrogen yield was accompanied by the deposition of polymer on the vessel wall.

  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. Detonation Initiation by Gradient Mechanism in Propane--Oxygen and Propane--Air Mixtures

    NASA Astrophysics Data System (ADS)

    Rakitin, Aleksandr; Popov, Ilya; Starikovskiy, Andrey; neqlab Team

    2011-10-01

    An experimental study of detonation initiation by high-voltage nanosecond gas discharge has been performed in smooth detonation tubes. A gradient mechanism was used to initiate detonations in stoichiometric propane-oxygen mixtures with different nitrogen dilution and in propane-air mixtures. Initial pressures from 0.2 to 1bar have been tested. Detonation was formed within 4 transverse tube sizes at initial pressures higher than 0.2 bar for the propane-oxygen mixture and higher than 0.8 bar for the diluted mixture with 40% of nitrogen. The discharge energy inputs were 0.2-0.3 J. The gradient mechanism of detonation formation similar to the one suggested by Zeldovich has been shown to be the governing process. For the mixture with air, a detonation tube with an annular discharge chamber has been designed and tested.

  14. 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.

  15. Emissions with butane/propane blends

    SciTech Connect

    1996-11-01

    This article reports on various aspects of exhaust emissions from a light-duty car converted to operate on liquefied petroleum gas and equipped with an electrically heated catalyst. Butane and butane/propane blends have recently received attention as potentially useful alternative fuels. Butane has a road octane number of 92, a high blending vapor pressure, and has been used to upgrade octane levels of gasoline blends and improve winter cold starts. Due to reformulated gasoline requirements for fuel vapor pressure, however, industry has had to remove increasing amounts of butane form the gasoline pool. Paradoxically, butane is one of the cleanest burning components of gasoline.

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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

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

    PubMed

    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

  5. 40 CFR 1065.341 - CVS, PFD, and batch sampler verification (propane check).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... propane, such as CO2 or CO. A failed propane check might indicate one or more problems that may require...) Perform the propane check as follows: (1) For batch HC sampling, connect clean storage media, such as... background. (3) Calculate total C3H8 mass based on your CVS and HC data as described in § 1065.650 (40...

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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...

  11. 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.

  12. 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.

  13. 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

    ...\\ The metal cylinders can hold approximately 25 pounds of propane, but for safety reasons, can only be..., either directly or indirectly: Cylinder preparation (including cleaning, rust removal, repainting...

  14. Design considerations for NDE systems in a factory setting and the application to transmission manufacture at the Chrysler Transmission Plant in Kokomo, Indiana

    SciTech Connect

    LaChapell, M.; Perkins, D.E.; Schneberk, D.J.; Erb, S.H.; Nicholson, R.E.

    1994-10-01

    Chrysler Corp. and LLNL have entered into a collaboration to enhance the NDE technology at the Kokomo transmission plant. The project spans 3 years and a wide variety of different projects. Goals are making NDE automated, reliable, and capable of avoiding destructive testing. This requires NDE systems to be better utilized by quality teams on the shop floor and better connected for providing in one place a sufficient set of data for identifying problems in a manufacturing operation, and prescribing an adjustment. The approach is illustrated on two different processes, laser welding and pressure die casting; in each case data are combined from different NDE systems to enable a decision on an adjustment in process variables.

  15. 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

  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 157.220 - Dedicated clean ballast tanks: Standards.

    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 Design and Equipment § 157.220 Dedicated clean ballast tanks: Standards. (a) Cargo tanks that are designated as dedicated clean ballast...

  19. 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...

  20. 33 CFR 157.220 - Dedicated clean ballast tanks: Standards.

    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 Design and Equipment § 157.220 Dedicated clean ballast tanks: Standards. (a) Cargo tanks that are designated as dedicated clean ballast...

  1. 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...

  2. 33 CFR 157.220 - Dedicated clean ballast tanks: Standards.

    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 Design and Equipment § 157.220 Dedicated clean ballast tanks: Standards. (a) Cargo tanks that are designated as dedicated clean ballast...

  3. 33 CFR 157.220 - Dedicated clean ballast tanks: Standards.

    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 Design and Equipment § 157.220 Dedicated clean ballast tanks: Standards. (a) Cargo tanks that are designated as dedicated clean ballast...

  4. 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...

  5. 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...

  6. 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

  7. 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)

  8. 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

  9. Dedication: John W. Wright, 1929-1978

    NASA Astrophysics Data System (ADS)

    Wright, John W.

    1980-09-01

    The death of John W. Wright in an automobile accident on November 20, 1978, came as a great shock to all who knew him. His family and friends lost a stimulating, compassionate human being whose many-faceted personality they greatly admired. The scientific community working on remote sensing of the air-water interface lost one of its pioneers and leaders. To dedicate this issue of the Journal of Geophysical Research to Dr. Wright seems a fitting tribute to his many scientific achievements.

  10. Dedicated robotic servicing for the space station

    NASA Technical Reports Server (NTRS)

    Thompson, R. F.; Arnold, G.; Gutow, D.

    1987-01-01

    The concept of a series of dedicated robotics manipulators that would be resident in the subsystems of the Space Station is presented. These would be used to do Orbital Replacement Unit (ORU) exchanges, inspection of the components, and in certain cases subsystem assembly. By performing these well-definded tasks automatically, higher crew productivity would be achieved. In order to utilize the robots effectively, ORU's must be designed to allow remote release and quick disconnection of the electrical, fluid, and thermal connections. The robot must be of a modular design for ease of maintenance and must have an adaptive control capability to make-up for slight errors in programming.

  11. Dedicated breast computed tomography: Basic aspects.

    PubMed

    Sarno, Antonio; Mettivier, Giovanni; Russo, Paolo

    2015-06-01

    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&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. PMID:26127031

  12. 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.

  13. 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.

  14. 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.

  15. Novel adsorption distillation hybrid scheme for propane/propylene separation

    SciTech Connect

    Kumar, R.; Golden, T.C.; White, T.R.; Rokicki, A. )

    1992-12-01

    A novel adsorption-distillation hybrid scheme is proposed for propane/propylene separation. The suggested scheme has potential for saving up to [approximately]50% energy and [approximately]15-30% in capital costs as compared with current technology. The key concept of the proposed scheme is to separate olefins from alkanes by adsorption and then separate individual olefins and alkanes by simple distillation, thereby eliminating energy intensive and expensive olefin-alkane distillation. A conceptual flow schematic for the proposed hybrid scheme and potential savings are outlined.s

  16. 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...

  17. 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.

  18. 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.

  19. 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.

  20. Comparing economic and environmental impacts of propane, CNG, methanol

    SciTech Connect

    Not Available

    1993-12-01

    How well does propane stack up as a motor fuel against CNG, methanol, ethanol, and gasoline This question has been addressed -- indirectly -- in various studies made by David Gushee over the period of time since the Congress first began seriously considering the advocacy of alternative fuels as a means of improving urban air quality, increasing energy security, reducing oil imports, increasing domestic content of transportation fuels, and reducing emissions of greenhouse gases. A brief overview of the comparative advantages and disadvantages of the various alternative motor fuels, with particular emphasis on propane, was presented by Gushee at the NPGA Governmental Affairs Conference in Washington, DC in October. Subsequently, at BPN's request, he supplied copies of the slides he showed on that occasion, together with copies of certain presentations he has made in the past based upon his studies. The following is a paraphrased and abridged rewrite -- in the interest of saving space -- of a presentation made by Gushee at a meeting of the National Conference of State Legislatures. In his address, Gushee analyzed the impacts of the various fuels on both the economics of transportation and the environment.

  1. 40 CFR 1065.341 - CVS and batch sampler verification (propane check).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CO2 or CO. A failed propane check might indicate one or more problems that may require corrective...) Perform the propane check as follows: (1) For batch HC sampling, connect clean storage media, such as... batch sampler's storage media (such as a PM filter). If the absolute pressure at this location is...

  2. 40 CFR 1065.341 - CVS and batch sampler verification (propane check).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false CVS and batch sampler verification... Measurements § 1065.341 CVS and batch sampler verification (propane check). (a) A propane check serves as a CVS... also serves as a batch-sampler verification to determine if there is a discrepancy in a batch...

  3. Reaction network and kinetics of propane oxydehydrogenation over nickel cobalt molybdate

    SciTech Connect

    Stern, D.L.; Grasselli, R.K.

    1997-04-15

    Reaction kinetics and a proposed mechanism for the oxydehydrogenation of propane over Ni{sub 0.5}Co{sub 0.5}MoO{sub 4}/SiO{sub 2} are described. The reaction pathway proceeds by propane oxydehydrogenation yielding propylene as the exclusive primary product. The propylene thus formed oxidizes further primarily to acrolein, which oxides still further to waste products CO and CO{sub 2}, and acrylic acid. The relative rate of acrolein formation from propylene is 3.5 times that of propylene formation from propane, the rate of CO{sub 2}, formation from acrolein is 13 times that of acrolein formation from propylene, and the rate of CO{sub 2}, formation from acrolein is 46 times that of propylene formation from propane. Kinetic isolation of intermediates is therefore imperative for the recovery of practical amounts of useful products, and might be achievable through dioxygen limitation in the feed or utilization of cocatalysts to produce more stable intermediates. The selective oxidation of propane to propylene and propylene to acrolein are both zero order in oxygen and first order in hydrocarbon (propane and propylene, respectively). Deep oxidation of propane (to CO and CO{sub 2}) is half order in oxygen and first order in propane, while deep oxidation of propylene exhibits Langmuir type dependence on hydrocarbon and is half order in oxygen. 17 refs., 7 figs.

  4. 40 CFR 721.533 - Propane, 1,1,1,3,3-pentachloro-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.533 Propane, 1,1,1,3,3-pentachloro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as propane, 1,1,1,3,3-pentachloro- (PMN...

  5. 40 CFR 721.533 - Propane, 1,1,1,3,3-pentachloro-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.533 Propane, 1,1,1,3,3-pentachloro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as propane, 1,1,1,3,3-pentachloro- (PMN...

  6. Availability of Canadian imports to meet U.S. demand for ethane, propane and butane

    SciTech Connect

    Hawkins, D.J.

    1996-12-31

    Historically, Canada has had a surplus of ethane, propane and butane. Almost all of the available propane and butane in Canadian natural gas streams is recovered. While there is significant ethane recovery in Canada, ethane that cannot be economically sold is left in the gas streams. All of the surplus Canadian ethane and most of the Canadian surplus propane and butane is exported to the US. Some volumes of Canadian propane and butane have been moved offshore by marine exports to the Asia-Pacific region or South America, or directly to Mexico by rail. Essentially all of the Canadian ethane, 86% of the propane and 74% of the butane are recovered by gas processing. Canadian natural gas production has increased significantly over the last 10 years. Canadian gas resources in the Western Canadian Sedimentary Basin should permit further expansion of gas exports, and several gas pipeline projects are pending to expand the markets for Canadian gas in the US. The prospective increase in Canadian gas production will yield higher volumes of ethane, propane and butane. While there is a potential to expand domestic markets for ethane, propane and butane, a significant part of the incremental production will move to export markets. This paper provides a forecast of the expected level of ethane, propane and butane exports from Canada and discusses the supply, demand and logistical developments which may affect export availability from Canada.

  7. beta-Adrenergic blocking agents. 18. 1-(Aryloxy)-3-(arylthioalkylamino)propan-2-ols and 1-substituted alkylthioamino-3-(aryloxy)propan-2-ols.

    PubMed

    Tucker, H; Coope, J F

    1978-08-01

    The synthesis is described of a seris of derivaties of 1-(aryloxy)-3-(arylthioalkylamiho)propan-2-ols and 1-(alkylthioamino)- and 1-(aralkylamino)-3-(aryloxy)propan-2-ols. These compounds were investigated for their beta-adrenoreceptor blocking properties and their selectivity of action for the cardiac beta1 receptor. The structure-activity relationships are discussed with particular reference to the effects of the sulfur, sulfoxide, and sulfone groups on beta-adrenoreceptor blocking potency and selectivity.

  8. Freon or propane: new design methods give a choice for small gas-processing plants

    SciTech Connect

    Love, D.L.

    1986-03-10

    Propane, and sometimes ammonia, have been the major refrigerants considered for refrigeration in liquid extraction plants. Freon was considered only for automotive and building air conditioning. With modular plants on skids becoming more popular for small volume applications, less-expensive equipment approaches are required to economically justify these small projects. Commercial and residential design methods can be used for refrigerated liquid extraction. They can significantly reduce the cost, compared to propane, for small volume applications. Although it appears to be a simple substitution of freon for propane, there are many complications in using freon. They include major changes in materials, and in chiller and compressor design. Love Process Engineering Inc. (LPE) has conducted extensive research on freon and propane plants for modular applications. This article will not discuss detailed design requirements, but compare freon and propane in the initial selection of project development for small volume applications.

  9. An analysis of US propane markets, winter 1996-1997

    SciTech Connect

    1997-06-01

    In late summer 1996, in response to relatively low inventory levels and tight world oil markets, prices for crude oil, natural gas, and products derived from both began to increase rapidly ahead of the winter heating season. Various government and private sector forecasts indicated the potential for supply shortfalls and sharp price increases, especially in the event of unusually severe winter weather. Following a rapid runup in gasoline prices in the spring of 1996, public concerns were mounting about a possibly similar situation in heating fuels, with potentially more serious consequences. In response to these concerns, the Energy Information Administration (EIA) participated in numerous briefings and meetings with Executive Branch officials, Congressional committee members and staff, State Energy Offices, and consumers. EIA instituted a coordinated series of actions to closely monitor the situation and inform the public. This study constitutes one of those actions: an examination of propane supply, demand, and price developments and trends.

  10. The oxidative dehydrogenation of propane on molybdenum based catalysts

    SciTech Connect

    Meunier, F.C.; Yasmeen, A.; Ross, J.R.H.

    1996-10-01

    In the past few years, there has been much interest in the selective oxidation of light hydrocarbons, either as an industrial or academic matter. One of these reactions, the propane dehydrogenation to propene, has been carried out the most successfully on vanadia supported on magnesia or niobia. As a high selectivity of niobia supported molybdena was also observed, molybdenum based catalysts have been studied, in an attempt to improve their activities. A number of possible supports were tested. Among these, titania and alumina gave the most selective catalysts at iso-conversion, providing there was a sufficient molybdena loading. In addition to propene and carbon oxides, several oxygenated compounds were observed. Additions of vanadium and niobium to the titania supported molybdena gave an improvement in the catalytic activity. The same conversion and selectivity were obtained at a temperature up to 100K lower.

  11. 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.

  12. 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.

  13. 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.

  14. Effect of hydrogen injection stability and emissions of an experimental premixed prevaporized propane burner

    NASA Technical Reports Server (NTRS)

    Anderson, D. N.

    1975-01-01

    Hydrogen in quantities up to 5 percent by weight of the total fuel flow was injected into a premixed propane burner. The hydrogen was either premixed with the propane and air upstream of the burner or introduced as a torch at the flameholder. Emissions of total nitrogen oxides, carbon monoxide, and unburned hydrocarbon are reported as are combustion efficiencies and lean blowout limits. To maintain at least 99 percent combustion efficiency at a 700 K inlet mixture temperature with no hydrogen added, it was necessary to burn with a propane equivalence ratio of 0.525. When 4 percent hydrogen was premixed with the propane and air, a combustion efficiency greater than 99 percent was recorded at a propane equivalence ratio of 0.425. The total nitrogen oxides (NOx) emissions corresponding to these two conditions were 0.8 g NO2/kg equivalent propane and 0.44 g NO2/kg equivalent propane, respectively. The hydrogen torch did not reduce NOx emissions.

  15. 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)

  16. Effect of temperature and pressure on the dynamics of nanoconfined propane

    SciTech Connect

    Gautam, Siddharth Liu, Tingting Welch, Susan; Cole, David; Rother, Gernot; Jalarvo, Niina; Mamontov, Eugene

    2014-04-24

    We report the effect of temperature and pressure on the dynamical properties of propane confined in nanoporous silica aerogel studied using quasielastic neutron scattering (QENS). Our results demonstrate that the effect of a change in the pressure dominates over the effect of temperature variation on the dynamics of propane nano-confined in silica aerogel. At low pressures, most of the propane molecules are strongly bound to the pore walls, only a small fraction is mobile. As the pressure is increased, the fraction of mobile molecules increases. A change in the mechanism of motion, from continuous diffusion at low pressures to jump diffusion at higher pressures has also been observed.

  17. 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.

  18. Coherence in Professional Education: Does It Foster Dedication and Identification?

    ERIC Educational Resources Information Center

    Heggen, Kåre; Terum, Lars Inge

    2013-01-01

    This article examines the impact of professional education on students' dedication to and identification with a profession. The premise is that professional education is not only about knowledge acquisition and reasoning but also about attitudes and aspirations. In fostering dedication and identification, students' experiences of…

  19. 7. VARIABLEANGLE LAUNCHER DEDICATION PLAQUE SHOWING JAMES H. JENNISON (LEFT), ...

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

    7. VARIABLE-ANGLE LAUNCHER DEDICATION PLAQUE SHOWING JAMES H. JENNISON (LEFT), AND W.H. SAYLOR (RIGHT), AT THE DEDICATION CEREMONY, May 7, 1948. (Original photograph in possession of Dave Willis, San Diego, California.) - Variable Angle Launcher Complex, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

  20. 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

  1. 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.

  2. 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.

  3. 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...

  4. 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.

  5. 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. PMID:25577087

  6. 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.

  7. Mutagenic activity of halogenated propanes and propenes: effect of bromine and chlorine positioning.

    PubMed

    Låg, M; Omichinski, J G; Dybing, E; Nelson, S D; Søderlund, E J

    1994-10-01

    A series of halogenated propanes and propenes were studied for mutagenic effects in Salmonella typhimurium TA100 in the absence or presence of NADPH plus liver microsomes from phenobarbital-induced rats as an exogenous metabolism system. The cytotoxic and mutagenic effects of the halogenated propane 1,2-dibromo-3-chloropropane (DBCP) has previously been studied in our laboratories. These studies showed that metabolic activation of DBCP was required to exert its detrimental effects. All of the trihalogenated propane analogues were mutagenic when the microsomal activation system was included. The highest mutagenic activity was obtained with 1,2,3-tribromopropane, with approximately 50-fold higher activity than the least mutagenic trihalogenated propane, 1,2,3-trichloropropane. The order of mutagenicity was as follows: 1,2,3-tribromopropane > or = 1,2-dibromo- 3-chloropropane > 1,3-dibromo-2-chloropropane > or = 1,3-dichloro-2-bromopropane > 1-bromo-2,3-dichloropropane > 1,2,3-trichloropropane. Compared to DBCP, the dihalogenated propanes were substantially less mutagenic. Only 1,2-dibromopropane was mutagenic and its mutagenic potential was approximately 1/30 of that of DBCP. In contrast to DBCP, 1,2-dibromopropane showed similar mutagenic activity with and without the addition of an activation system. The halogenated propenes 2,3-dibromopropene and 2-bromo-3-chloropropene were mutagenic to the bacteria both in the absence and presence of the activation system, whereas 2,3-dichloropropene did not show any mutagenic effect. The large differences in mutagenic potential between the various halogenated propanes and propenes are proposed to be due to the formation of different possible proximate and ultimate mutagenic metabolites resulting from the microsomal metabolism of the various halogenated propanes and propenes, and to differences in the rate of formation of the metabolites. Pathways are proposed for the formation of genotoxic metabolites of di- and trihalogenated

  8. 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.

  9. Preparation of platinum nanoparticle catalyst for propane dehydrogenation.

    PubMed

    Li, Jun; Wang, Jun; Ma, Zhanhua; Sun, Lanyi; Hu, Yangdong

    2014-09-01

    Supported Pt nanoparticle catalysts were prepared by combing a chemical reduction method with an ultrasonic sonication loading method. Several techniques including transmission electron microscopy (TEM), nitrogen sorption technique and pyridine adsorption Fourier-transform infrared (Py-IR) were applied to characterize the physicochemical properties of these catalysts. The catalytic performance of catalysts was evaluated in the dehydrogenation of propane. The influence of the preparation method of Pt nanoparticles, the ratio of Polyvinyl Pyrrolidone (PVP) to Pt, loading method and different supports on the catalytic performance was investigated. PVP is useful for controlling the size of Pt nanoparticles and a PVP/Pt ratio of 15 is favorable to achieve a good catalytic performance. NaBH4 reduction is better than ethanol refluxing in preparing Pt nanoparticles. The ultrasonic sonication is effective to load the Pt nanoparticles onto the support channels. The mesoporous alumina proved to be a good catalyst support due to its high surface area and unique pore structure. PMID:25924358

  10. Study of the Low Temperature Oxidation of Propane

    PubMed Central

    Cord, Maximilien; Husson, Benoit; Huerta, Juan Carlos Lizardo; Herbinet, Olivier; Glaude, Pierre-Alexandre; Fournet, René; Sirjean, Baptiste; Battin-Leclerc, Frédérique; Ruiz-Lopez, Manuel; Wang, Zhandong; Xie, Mingfeng; Cheng, Zhanjun; Qi, Fei

    2013-01-01

    The low-temperature oxidation of propane was investigated using a jet-stirred reactor at atmospheric pressure and two methods of analysis: gas chromatography and synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) with direct sampling through a molecular jet. The second method allowed the identification of products, such as molecules with hydroperoxy functions, which are not stable enough to be detected by gas chromatography. Mole fractions of the reactants and reaction products were measured as a function of the temperature (530-730 K), with a particular attention to reaction products involved in the low temperature oxidation, such as cyclic ethers, aldehydes, alcohols, ketones, and hydroperoxides. A new model has been obtained from an automatically generated one, which was used as a starting point, with a large number of re-estimated thermochemical and kinetic data. The kinetic data of the most sensitive reactions, i.e., isomerizations of alkylperoxy radicals and the subsequent decompositions, have been calculated at the CBS-QB3 level of theory. The model allows a satisfactory prediction of the experimental data. A flow rate analysis has allowed highlighting the important reaction channels. PMID:23181456

  11. 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

  12. 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

  13. Dedicated EPROM-based computer for distributed instrumentation control

    SciTech Connect

    Hunt, D.N.; O'Brien, D.W.

    1981-10-14

    The LLNL Nuclear Chemistry Counting Facility (NCCF) is being converted to a modern production facility. A computer network has been designed and built to implement this conversion. The outermost node of the computer network is a dedicated EPROM-based controller. The controller handles the details of driving the attached nuclear instrumentation, providing a standard interface to the remainder of the network. This paper addresses the design and the implementation of the dedicated instrumentation controller.

  14. 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.

  15. 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. PMID:26364888

  16. 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.

  17. 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.

  18. Dedication to Professor Hannspeter Winter (1941 2006): Dedication to Professor Hannspeter Winter (1941 2006)

    NASA Astrophysics Data System (ADS)

    McCullough, Bob

    2007-03-01

    Professor H Winter. It was with great sadness that we learnt of the death of colleague and friend Professor Hannspeter Winter in Vienna on the 8 November 2006. In memory of him and the contribution he made both to our conference and to the field of the physics of highly charged ions we dedicate these proceedings. Hannspeter was one of our distinguished invited speakers at HCI2006 and gave a talk on the status of the ITER programme. His invited paper on the subject is included in these proceedings. Hannspeter will be particularly remembered for his pioneering work on ion-surface interactions that, together with his colleagues at the Vienna University of Technology (TUW), has stimulated a worldwide experimental and theoretical interest in this field. He was appointed Director of the Institut fuer Allgemeine Physik at TUW in 1987 and using both his scientific and management skills has made it one of the leading university physics laboratories in the world. His research publications, of which there are 270, have inspired many others to work in the field of atomic and plasma physics. He was also a great European playing a major role in the EURATOM fusion programme, the European Physical Society and the International Union of Pure and Applied Physics and was an evaluator and advisory board member for many national and international institutions. Hannspeter was also an interesting and friendly social companion with interests in current affairs, music and fine wines and will be greatly missed both on a scientific and social level. Our condolences go to his wife Renate, son Dorian and his relatives. R W McCullough Co-chair HCI2006

  19. Extraction of Lutein Diesters from Tagetes Erecta using Supercritical CO2 and Liquid Propane.

    PubMed

    Skerget, Mojca; Bezjak, Miran; Makovšek, Katja; Knez, Zeljko

    2010-03-01

    The efficiency of high pressure extraction of lutein diesters from marigold (Tagetes erecta) flower petals has been investigated. The solvents used for extraction were supercritical carbon dioxide and liquid propane. Operating parameters were 300 bar and 40, 60 and 80 °C for CO2 and 100, 150, 200 bar and 40 and 60 °C for propane, respectively. The influence of process parameters on the total yield of extraction and content of lutein diesters in the extracts was investigated. The results show, that solvent power of propane for lutein diesters is approximately 3.5 times higher than of CO2. The calculation procedure based on the Fick's second law was applied to determine the diffusivities of lutein diesters during extraction from marigold flower petals for both extraction stages: a constant rate stage followed by a stage of decreasing rate. The mathematical model based on the Fick's second law well described the experimental extraction results.

  20. No. 2 heating oil/propane program. Final report, 1990/91

    SciTech Connect

    McBrien, J.

    1991-06-01

    During the 1990/91 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 1990 through March 1991. This final report begins with an overview of the unique events which had an impact on the reporting period. Next, the report summarizes the results from the residential heating oil and propane price surveys conducted by DOER over the 1990/91 heating season. The report also incorporates the wholesale heating oil and propane prices and inventories collected by the EIA and distributed to the states.

  1. Number 2 heating oil/propane program. Final report, 1991/92

    SciTech Connect

    McBrien, J.

    1992-06-01

    During the 1991--92 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, 1991 through March, 1992. This final report begins with an overview of the unique events which had an impact on the reporting period. Next, the report summarizes the results from the residential heating oil and propane price surveys conducted by DOER over the 1991--1992 heating season. The report also incorporates the wholesale heating oil and propane prices and inventories collected by the EIA and distributed to the states. Finally, the report outlines DOER`s use of the data and responses to the events which unfolded during the 1991--1992 heating season.

  2. Being Dedicated in the Film The American Nurse.

    PubMed

    Baumann, Steven L; Ganzer, Christine Anne

    2016-01-01

    The focus of this humanbecoming hermeneutic study of graduate nursing students' reflections is on being dedicated as portrayed in the documentary film, The American Nurse. Nursing students were invited to a public screening of the film, with the director, Carolyn Jones, and asked to write a brief reflective essay on "what is the meaning of being dedicated depicted in the film The American Nurse." The perspective is to be the humanbecoming school of thought. The participants were 20 nurses either in a graduate or doctoral nursing program at the time of this study. The emergent meanings of the study are offered to enhance knowledge and understanding of being dedicated. The use of documentary film to expand graduate nursing students' awareness of global issues is also considered. PMID:26660779

  3. 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.

  4. Dedicated operating room for emergency surgery improves access and efficiency

    PubMed Central

    Heng, Marilyn; Wright, James G.

    2013-01-01

    Background Scheduling emergency cases among elective surgeries often results in prolonged waits for emergency surgery and delays or cancellation of elective cases. We evaluated the benefits of a dedicated operating room (OR) for emergency procedures available to all surgical services at a large children’s hospital. Methods We compared a 6-month period (January 2009 to June 2009) preimplementation with a 6-month period (January 2010 to June 2010) postimplementation of a dedicated OR. We evaluated OR use, wait times, percentage of cases done within and outside of access targets, off-hours surgery, cancellations, overruns and length of stay. Results Preimplementation, 1069 of the 5500 surgeries performed were emergency cases. Postimplementation, 1084 of the 5358 surgeries performed were emergency cases. Overall use of the dedicated OR was 53% (standard deviation 25%) postimplementation. Excluding outliers, the average wait time for priority 3 emergency patients decreased from 11 hours 8 minutes to 10 hours 5 minutes (p = 0.004). An increased proportion of priority 3 patients, from 52% to 58%, received surgery within 12 hours (p = 0.020). There was a 9% decrease in the proportion of priority 3 cases completed during the evening and night (p < 0.001). The elective surgical schedule benefited from the dedicated OR, with a significant decrease in cancellations (1.5% v. 0.7%, p < 0.001) and an accumulated decrease of 5211 minutes in overrun minutes in elective rooms. The average hospital stay after emergency surgery decreased from 16.0 days to 14.7 days (p = 0.12) following implementation of the dedicated OR. Conclusion A dedicated OR for emergency cases improved quality of care by decreasing cancellations and overruns in elective rooms and increasing the proportion of priority 3 patients who accessed care within the targeted time. PMID:23706847

  5. Operating Dedicated Data Centers - Is It Cost-Effective?

    NASA Astrophysics Data System (ADS)

    Ernst, M.; Hogue, R.; Hollowell, C.; Strecker-Kellog, W.; Wong, A.; Zaytsev, A.

    2014-06-01

    The advent of cloud computing centres such as Amazon's EC2 and Google's Computing Engine has elicited comparisons with dedicated computing clusters. Discussions on appropriate usage of cloud resources (both academic and commercial) and costs have ensued. This presentation discusses a detailed analysis of the costs of operating and maintaining the RACF (RHIC and ATLAS Computing Facility) compute cluster at Brookhaven National Lab and compares them with the cost of cloud computing resources under various usage scenarios. An extrapolation of likely future cost effectiveness of dedicated computing resources is also presented.

  6. 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... Facilities § 102-74.280 Are privately owned vehicles converted for propane carburetion permitted in underground parking facilities? Federal agencies must not permit privately owned vehicles converted...

  7. 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...

  8. [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.

  9. 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 Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  10. 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 Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  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 Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  12. 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 Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  13. 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

  14. 75. FIRST TEST SHOT OF THE VAL AT THE DEDICATION ...

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

    75. FIRST TEST SHOT OF THE VAL AT THE DEDICATION CEREMONIES AS SEEN FROM A FIXED CAMERA STATION, May 7, 1948. (Original photograph in possession of Dave Willis, San Diego, California.) - Variable Angle Launcher Complex, Variable Angle Launcher, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

  15. 76. FIRST TEST SHOT OF THE VAL AT THE DEDICATION ...

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

    76. FIRST TEST SHOT OF THE VAL AT THE DEDICATION CEREMONIES AS SEEN FROM THE OBSERVATION DECK ABOVE THE CONTROL STATION, May 7, 1948. - Variable Angle Launcher Complex, Variable Angle Launcher, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

  16. Commercial Grade Item (CGI) Dedication for Leak Detection Relays

    SciTech Connect

    KOCH, M.R.; JOHNS, B.R.

    1999-12-21

    This Test Plan provides a test method to dedicate the leak detection relays used on the new Pumping and Instrumentation Control (PIC) skids. The new skids are fabricated on-site. The leak detection system is a safety class system per the Authorization Basis.

  17. Commercial Grade Item (CGI) Dedication for Leak Detection Relays

    SciTech Connect

    JOHNS, B.R.

    1999-05-05

    This Test Plan provides a test method to dedicate the leak detection relays used on the new Pumping and Instrumentation Control (PIC) skids. The new skids are fabricated on-site. The leak detection system is a safety class system per the Authorization Basis.

  18. Commercial Grade Item (CGI) Dedication for Leak Detection Relays

    SciTech Connect

    KOCH, M.R.

    2000-02-28

    This Test Plan provides a test method to dedicate the leak detection relays used on the new Pumping Instrumentation and Control (PIC) skids. The new skids are fabricated on-site. The leak detection system is a safety class system per the Authorization Basis.

  19. 40 CFR 1065.341 - CVS and batch sampler verification (propane check).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CO2 or CO. A failed propane check might indicate one or more problems that may require corrective... batch HC sampling, connect clean storage media, such as evacuated bags. (2) Operate HC measurement... sample near the location of the batch sampler's storage media (such as a PM filter). If the...

  20. 40 CFR 1065.341 - CVS and batch sampler verification (propane check).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CO2 or CO. A failed propane check might indicate one or more problems that may require corrective... batch HC sampling, connect clean storage media, such as evacuated bags. (2) Operate HC measurement... sample near the location of the batch sampler's storage media (such as a PM filter). If the...

  1. 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.

  2. Site-dependent catalytic activity of graphene oxides towards oxidative dehydrogenation of propane.

    PubMed

    Tang, Shaobin; Cao, Zexing

    2012-12-28

    Graphene oxides (GOs) may offer extraordinary potential in the design of novel catalytic systems due to the presence of various oxygen functional groups and their unique electronic and structural properties. Using first-principles calculations, we explore the plausible mechanisms for the oxidative dehydrogenation (ODH) of propane to propene by GOs and the diffusion of the surface oxygen-containing groups under an external electric field. The present results show that GOs with modified oxygen-containing groups may afford high catalytic activity for the ODH of propane to propene. The presence of hydroxyl groups around the active sites provided by epoxides can remarkably enhance the C-H bond activation of propane and the activity enhancement exhibits strong site dependence. The sites of oxygen functional groups on the GO surface can be easily tuned by the diffusion of these groups under an external electric field, which increases the reactivity of GOs towards ODH of propane. The chemically modified GOs are thus quite promising in the design of metal-free catalysis. PMID:22801590

  3. Propane and butane emission sources to ambient air of Mexico City metropolitan area.

    PubMed

    Jaimes, L; Sandoval, J

    2002-04-22

    Samples of volatile organic compounds (VOCs) were collected in a smog chamber in order to determine whether automotive exhausts or LP Gas emissions play a greater role in the source of propane and butane, which affect ozone formation and other pollutants in the ambient air of the Mexico City metropolitan area (MCMA). These samples were collected in April 1995 during mornings and evenings. The testing methodology used for measuring exhaust emission were FTP or EPA-74 tests, and SHED type tests were also conducted in order to evaluate evaporative emissions. The finding from analysis of the VOCs collected in the morning demonstrate that in the atmosphere, propane concentrations are higher than that of butane but the reverse in evaporative and exhaust emissions, with the concentration of propane lower than that of butane. Our conclusion is that most of C3 and C4 in the ambient air comes from LP gas and not vehicle exhaust or evaporative emission, due to the higher levels of propane than butane in its formulation. The analysis of VOCs also indicates that although the conversion (in the smog chamber) of alkanes is low during the day, due to the high initial concentration, their contribution in the reaction mechanism to produce ozone can be appreciable.

  4. 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...

  5. 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...

  6. 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...

  7. Evaluation of propane combustion traps for collection of Phlebotomus papatasi (Scopoli) in southern Israel.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Traps used for mosquitoes can possibly used to capture phlebotomine sand flies as well, but little testing has been done. Traps powered by propane could be extremely useful because most produce their own carbon dioxide (CO2), which can increase the number of sand flies captured. Scientists at the US...

  8. 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.

  9. 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.

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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

  18. Low-temperature complete combustion of a dilute mixture of methane and propane over transition-metal-doped ZrO2 catalysts: effect of the presence of propane on methane combustion.

    PubMed

    Choudhary, V R; Deshmukh, G M; Pataskar, S G

    2005-04-01

    Complete combustion of dilute methane alone or a dilute mixture of methane and propane over transition-metal (viz. Mn, Co, Cr, Fe, and Ni)-doped ZrO2 (cubic) catalysts at different temperatures (523-873 K) and a space velocity of 51,000 cm3 x g(-1) x h(-1) has been investigated for controlling methane and propane emissions from exhaust gases. The catalysts are compared for their catalytic ignition temperature and activity in the combustion of propane and methane in the presence of each other. The methane combustion activity of all the catalysts is strongly influenced by the presence of propane; it is decreased markedly. In the combustion of mixed methane and propane the Mn-doped ZrO2 and Cr-doped ZrO2 catalysts show the highest activity in the combustion of methane and propane, respectively; the Ni-doped ZrO2 shows the lowest activity in both cases. In the combustion of mixed methane and propanethe propane combustion is enhanced butthe methane combustion retarded when the Cr-doped ZrO2 and Mn-doped ZrO2 catalysts in a 1:1 ratio are used together in different ways (mixed or in layers).

  19. 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.

  20. Gas-phase simulated moving bed: Propane/propylene separation on 13X zeolite.

    PubMed

    Martins, Vanessa F D; Ribeiro, Ana M; Plaza, Marta G; Santos, João C; Loureiro, José M; Ferreira, Alexandre F P; Rodrigues, Alírio E

    2015-12-01

    In the last years several studies were carried out in order to separate gas mixtures by SMB technology; however, this technology has never been implemented on an industrial scale. In the present work, a gas phase SMB bench unit was built and tested for the separation of propane and propylene mixtures, using 13X zeolite extrudates as adsorbent and isobutane as desorbent. Three experiments were performed to separate propane/propylene by gas phase SMB in the bench scale unit with a 4-2-2 configuration, i.e., open loop circuit by suppressing section IV (desorbent regeneration followed by a recycle). Consequently, all the experiments were conducted using an external supply of pure isobutane as desorbent. Parameters such as switching time, extract and raffinate stream flow rates were changed to improve the efficiency of the process. Experimental results have shown that it is feasible to separate propylene from propane by gas phase SMB at a bench scale and that this process is a potential candidate to replace the conventional technologies for the propane/propylene separation. The performance parameters obtained are very promising for future development of this technology, since propylene was obtained in the extract stream with a purity of 99.93%, a recovery of 99.51%, and a productivity of [Formula: see text] . Propane was obtained in the raffinate stream with a purity of 98.10%, a recovery of 99.73% and a productivity of [Formula: see text] . The success of the above mentioned bench scale tests is a big step for the future implementation of this technology in a larger scale.

  1. 33 CFR 157.225 - Dedicated clean ballast tanks operations: General.

    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 Dedicated Clean Ballast Tanks Operations § 157.225 Dedicated clean ballast tanks operations: General. The master of a tank vessel...

  2. 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...

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

    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 Dedicated Clean Ballast Tanks Operations § 157.225 Dedicated clean ballast tanks operations: General. The master of a tank vessel...

  4. 33 CFR 157.225 - Dedicated clean ballast tanks operations: General.

    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 Dedicated Clean Ballast Tanks Operations § 157.225 Dedicated clean ballast tanks operations: General. The master of a tank vessel...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 33 CFR 157.225 - Dedicated clean ballast tanks operations: General.

    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 Dedicated Clean Ballast Tanks Operations § 157.225 Dedicated clean ballast tanks operations: General. The master of a tank vessel...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 33 CFR 157.226 - Dedicated Clean Ballast Tanks Operations Manual: Procedures to be followed.

    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... 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...

  18. 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...

  19. 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...

  20. 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...

  1. Marine microbes rapidly adapt to consume ethane, propane, and butane within the dissolved hydrocarbon plume of a natural seep

    NASA Astrophysics Data System (ADS)

    Mendes, Stephanie D.; Redmond, Molly C.; Voigritter, Karl; Perez, Christian; Scarlett, Rachel; Valentine, David L.

    2015-03-01

    Simple hydrocarbon gases containing two to four carbons (ethane, propane, and butane) are among the most abundant compounds present in petroleum reservoirs, and are introduced into the ocean through natural seepage and industrial discharge. Yet little is known about the bacterial consumption of these compounds in ocean waters. To assess the timing by which microbes metabolize these gases, we conducted a three-phase study that tested and applied a radiotracer-based method to quantify the oxidation rates of ethane, propane, and butane in fresh seawater samples. Phase 1 involved the synthesis of tritiated ethane, propane, and butane using Grignard reagents and tritiated water. Phase 2 was a systematic assessment of experimental conditions, wherein the indigenous microbial community was found to rapidly oxidize ethane, propane, and butane. Phase 3 was the application of this tritium method near the Coal Oil Point seeps, offshore California. Spatial and temporal patterns of ethane, propane, and butane oxidation down current from the hydrocarbon seeps demonstrated that >99% of these gases are metabolized within 1.3 days following initial exposure. The oxidation of ethane outpaced oxidation of propane and butane with patterns indicating the microbial community responded to these gases by rapid adaptation or growth. Methane oxidation responded the slowest in plume waters. Estimates based on the observed metabolic rates and carbon mass balance suggest that ethane, propane, and butane-consuming microorganisms may transiently account for a majority of the total microbial community in these impacted waters.

  2. 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.

  3. 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.

  4. [A unit dedicated to minor victims of violence].

    PubMed

    Gignon, Maxime; Manaouil, Cécile; Jarde, Olvier

    2010-01-01

    Law 98-468 of 17th June 1998 enables hearings for minor victims of aggression or sexual assault to be filmed. This legal procedure can sometimes be traumatic. In the region of Picardie, units dedicated to underage victims have been developed. These units bring together all the relevant professionals in a reassuring environment suitable for children, in order to encourage the child to talk and to help make the whole procedure easier. PMID:20684393

  5. Methodology for creating dedicated machine and algorithm on sunflower counting

    NASA Astrophysics Data System (ADS)

    Muracciole, Vincent; Plainchault, Patrick; Mannino, Maria-Rosaria; Bertrand, Dominique; Vigouroux, Bertrand

    2007-09-01

    In order to sell grain lots in European countries, seed industries need a government certification. This certification requests purity testing, seed counting in order to quantify specified seed species and other impurities in lots, and germination testing. These analyses are carried out within the framework of international trade according to the methods of the International Seed Testing Association. Presently these different analyses are still achieved manually by skilled operators. Previous works have already shown that seeds can be characterized by around 110 visual features (morphology, colour, texture), and thus have presented several identification algorithms. Until now, most of the works in this domain are computer based. The approach presented in this article is based on the design of dedicated electronic vision machine aimed to identify and sort seeds. This machine is composed of a FPGA (Field Programmable Gate Array), a DSP (Digital Signal Processor) and a PC bearing the GUI (Human Machine Interface) of the system. Its operation relies on the stroboscopic image acquisition of a seed falling in front of a camera. A first machine was designed according to this approach, in order to simulate all the vision chain (image acquisition, feature extraction, identification) under the Matlab environment. In order to perform this task into dedicated hardware, all these algorithms were developed without the use of the Matlab toolbox. The objective of this article is to present a design methodology for a special purpose identification algorithm based on distance between groups into dedicated hardware machine for seed counting.

  6. 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.

  7. Operation of gas electron multiplier (GEM) with propane gas at low pressure and comparison with tissue-equivalent gas mixtures

    NASA Astrophysics Data System (ADS)

    De Nardo, L.; Farahmand, M.

    2016-05-01

    A Tissue-Equivalent Proportional Counter (TEPC), based on a single GEM foil of standard geometry, has been tested with pure propane gas at low pressure, in order to simulate a tissue site of about 1 μm equivalent size. In this work, the performance of GEM with propane gas at a pressure of 21 and 28 kPa will be presented. The effective gas gain was measured in various conditions using a 244Cm alpha source. The dependence of effective gain on the electric field strength along the GEM channel and in the drift and induction region was investigated. A maximum effective gain of about 5×103 has been reached. Results obtained in pure propane gas are compared with gas gain measurements in gas mixtures commonly employed in microdosimetry, that is propane and methane based Tissue-Equivalent gas mixtures.

  8. [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. PMID:26548032

  9. 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.

  10. ZrO2 -Based Alternatives to Conventional Propane Dehydrogenation Catalysts: Active Sites, Design, and Performance.

    PubMed

    Otroshchenko, Tatyana; Sokolov, Sergey; Stoyanova, Mariana; Kondratenko, Vita A; Rodemerck, Uwe; Linke, David; Kondratenko, Evgenii V

    2015-12-21

    Non-oxidative dehydrogenation of propane to propene is an established large-scale process that, however, faces challenges, particularly in catalyst development; these are the toxicity of chromium compounds, high cost of platinum, and catalyst durability. Herein, we describe the design of unconventional catalysts based on bulk materials with a certain defect structure, for example, ZrO2 promoted with other metal oxides. Comprehensive characterization supports the hypothesis that coordinatively unsaturated Zr cations are the active sites for propane dehydrogenation. Their concentration can be adjusted by varying the kind of ZrO2 promoter and/or supporting tiny amounts of hydrogenation-active metal. Accordingly designed Cu(0.05 wt %)/ZrO2 -La2 O3 showed industrially relevant activity and durability over ca. 240 h on stream in a series of 60 dehydrogenation and oxidative regeneration cycles between 550 and 625 °C. PMID:26566072

  11. [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.

  12. The frozen orbital approximation for calculating ionization energies with application to propane

    NASA Astrophysics Data System (ADS)

    Müller, Wolfgang; Nager, Christoph; Rosmus, Pavel

    1980-09-01

    In the frozen orbital approximation (FOA), the influence of reorganization on correlation contributions to ionization energies is neglected. It is particularly useful in calculations for large molecules because of the advantage that only one integral transformation is required for the calculation of all ionic states. In connection with the concept of independent orbital correlation contributions, the dimensions of the CI matrices can be drastically reduced. The method is applied to the calculation of the valence ionization energies of propane, and compared to more rigorous ab initio results and a recent calculation in which inner valence shell contributions to electron correlation are neglected. The ordering of the first three ionizations in the photoelectron spectrum of propane, which has not been definitively assigned, is shown to be 2B1(2b1),2A1(6a1) and 2B2(4b2), in agreement with Koopmans' theorem.

  13. 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.

  14. Hydrate equilibria for binary and ternary mixtures of methane, propane, isobutane, and n-butane; Effect of salinity

    SciTech Connect

    Paranjpe, S.G. ); Kamath, V.A.; Patil, S.L. ); Godpole, S.P. )

    1989-11-01

    This paper provides new experimental data on the phase behavior of gas hydrates for several binary and ternary mixtures of methane, propane, isobutane, and n-butane. After the molecular Kihara parameters for n-butane in the thermodynamic model were tuned, the predictions were in good agreement with the experimental data. The role of n-butane formation is explained, and the effect of salinity on the phase behavior of binary mixtures of propane/n-butane is determined.

  15. Comparison of Filters Dedicated to Speckle Suppression in SAR Images

    NASA Astrophysics Data System (ADS)

    Kupidura, P.

    2016-06-01

    This paper presents the results of research on the effectiveness of different filtering methods dedicated to speckle suppression in SAR images. The tests were performed on RadarSat-2 images and on an artificial image treated with simulated speckle noise. The research analysed the performance of particular filters related to the effectiveness of speckle suppression and to the ability to preserve image details and edges. Speckle is a phenomenon inherent to radar images - a deterministic noise connected with land cover type, but also causing significant changes in digital numbers of pixels. As a result, it may affect interpretation, classification and other processes concerning radar images. Speckle, resembling "salt and pepper" noise, has the form of a set of relatively small groups of pixels of values markedly different from values of other pixels representing the same type of land cover. Suppression of this noise may also cause suppression of small image details, therefore the ability to preserve the important parts of an image, was analysed as well. In the present study, selected filters were tested, and methods dedicated particularly to speckle noise suppression: Frost, Gamma-MAP, Lee, Lee-Sigma, Local Region, general filtering methods which might be effective in this respect: Mean, Median, in addition to morphological filters (alternate sequential filters with multiple structuring element and by reconstruction). The analysis presented in this paper compared the effectiveness of different filtering methods. It proved that some of the dedicated radar filters are efficient tools for speckle suppression, but also demonstrated a significant efficiency of the morphological approach, especially its ability to preserve image details.

  16. Isolation and Characterization of Ethane, Propane, and Butane Consuming Bacteria from Marine Hydrocarbon Seeps

    NASA Astrophysics Data System (ADS)

    Redmond, M. C.; Valentine, D. L.

    2005-12-01

    Three strains of ethane, propane, or butane consuming bacteria were isolated from marine hydrocarbon seep sediments at Coal Oil Point, off shore Santa Barbara, CA. These three isolates (MR1, MR2 and MR3) were capable of growth at natural environmental temperatures and salinity. Isolate MR2 was capable of growth on ethane or propane as the sole carbon source, isolate MR4 on propane or butane, and isolate MR3 on ethane, propane, or butane. All three isolates were also able to grow on other carbon-containing molecules, including ethanol, 1-propanol, 2-propanol, acetate, butyrate, sucrose, and dextrose, and isolates MR3 and MR4 were able to grow on 1-butanol and 2-butanol. None showed significant growth with methane, methanol, or formate as the sole carbon source. 16S rDNA sequencing indicated that isolate MR2 was most closely related to the gamma-Proteobacterium Pseudomonas stutzeri, while isolates MR3 and MR4 were both Gram-positive and most similar to Rhodococcus wratislaviensis and Rhodococcus opacus, respectively. Compared to methanotrophs, relatively little is known about the organisms that consume the C2-C4 alkanes, but both our isolates and the previously described species appear to be capable of metabolizing a wide variety of carbon compounds, including several common pollutants. The growth of these hydrocarbon-oxidizing bacteria on other organic compounds raises the possibility that the abundance and distribution of organic matter might be expected to impact the oxidation of C2-C4 hydrocarbons. Additional studies will further characterize the range of metabolism, and will investigate the importance of these organisms in natural hydrocarbon seep environments.

  17. 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.

  18. 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.

  19. Clear-PEM, a dedicated PET camera for mammography

    NASA Astrophysics Data System (ADS)

    Lecoq, P.; Varela, J.

    2002-06-01

    Preliminary results suggest that Positron Emission Mammography (PEM) can offer a noninvasive method for the diagnosis of breast cancer. Metabolic images from PEM contain unique information not available from conventional morphologic imaging techniques and aid in expeditiously establishing the diagnosis of cancer. A dedicated machine seems to offer better perspectives in terms of position resolution and sensitivity. This paper describes the concept of Clear-PEM, the system presently developed by the Crystal Clear Collaboration at CERN for an evaluation of this approach. This device is based on new crystals introduced by the Crystal Clear as well as on modern data acquisition techniques developed for the large experiments in high energy physics experiments.

  20. DEDICATED FILTER FOR DEFECTS CLUSTERING IN RADIOGRAPHIC IMAGE

    SciTech Connect

    Sikora, R.; Swiadek, K.; Chady, T.

    2009-03-03

    Defect clusters such as linear or clustered porosity are in some cases even more important than single flaws. This paper presents two methods of defect clustering and algorithm for calculation of distances between flaws in digital radiographic image. Dedicated lookup table based filter is used for calculation of distances between objects in the specified range. For defect clustering two functions were developed. First one is based on MMD (Minimum Mean Distance) algorithm. Second one uses hierarchical procedures for clustering defects of various types, shapes and size.

  1. 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

  2. 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.

  3. Direct evidence of active surface reconstruction during oxidative dehydrogenation of propane over VMgO catalyst

    SciTech Connect

    Pantazidis, A.; Mirodatos, C.; Burrows, A.; Kiely, C.J.

    1998-07-25

    This paper presents a thorough investigation of an optimized VMgO catalyst (14 wt% V) for the oxidative dehydrogenation of propane, carried out in order to elucidate the nature and behavior of the active surface. The catalyst morphology and the surface composition are studied by means of HREM, XPS, UV-vis, XRD, and in-situ electrical conductivity techniques, as a function of the gaseous environments of the catalyst. The active surface is shown to be essentially a monolayer of amorphous VO{sub 4}{sup 3{minus}} units scattered over the magnesia as isolated and polymeric species. These surface vanadia units are found to stabilize an unusual polar (111) orientation of MgO up to temperatures of 800 C. A direct and outstanding evidence of a totally reversible phenomenon of order/disorder restructuration of this V overlayer is provided in conjunction with the redox state of the surface depending on the properties of the surrounding atmosphere (reductive or oxidative). These fast surface phenomena are assumed to determine the elementary steps of propane activation within the overall oxidative dehydrogenation of propane (ODHP) process.

  4. The interaction of water mists and premixed propane-air flames under low-gravity conditions

    NASA Astrophysics Data System (ADS)

    Abbud-Madrid, Angel; Riedel, Edward P.; McKinnon, J. Thomas

    1999-01-01

    A preliminary investigation of the effect of water mists on premixed flame propagation in a cylindrical tube under low-gravity conditions has been conducted to define the scientific and technical objectives of the experiments to be performed on the Space Shuttle and International Space Station microgravity environments. The inhibiting characteristics of water mists in propagating flames of propane-air mixtures at various equivalence ratios are studied. The effects of droplet size and concentration on the laminar flame speed are used as the measure of fire suppression efficacy. Flame speed and propagation behavior are monitored by a video camera. Reduced gravity is obtained with an aircraft flying parabolic trajectories. Measurements and qualitative observations from the low-gravity experiments clearly show the effect of water mist on flame speed abatement, flame shape, and radiant emission. For lean propane-air mixtures, the flame speed increases at first with low water-mist concentrations and then decreases below its dry value when higher water-mist volumes are introduced in the tube. This phenomenon may be due in part to the heating of the unburned mixture ahead of the flame as a result of radiation absorption by the water droplets. For rich propane-air mixtures, similar behavior of flame speed vs. water concentration is encountered but in this case is mostly due to the formation of cellular flames. At high water loads both lean and rich flames exhibit extinction before reaching the end of the tube.

  5. 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.

  6. A propane-filled bubble chamber as a time-independent gamma burst spectrometer

    SciTech Connect

    Browning, J.F.; Ruiz, C.L.; Cooper, G.W.; Lerche, R.A.

    1996-12-31

    A bubble chamber to be used as a gamma burst spectrometer in Inertial Confinement Fusion research has been proposed. Freon-115 was initially chosen as the working fluid of the bubble chamber due to its larger intrinsic efficiency, low operating temperature and pressure as well as its environmentally benign nature. Initial calculations indicate poor resolution over the energy range of interest, several keV to approximately 20 MeV. Evaluation led the author to consider propane as the working fluid. The resolution ({Delta}p/p) for gamma-ray energies of 2 MeV and 20 Mev are 22.1% and 6.4%, respectively, an improvement of approximately a factor 3. To further enhance the resolution of the chamber they propose increasing the magnetic field strength from 1.5 tesla to 2.0 tesla. They present operating parameters for the propane compared with that of the freon. The simulation tool GEANT will be used to model the response of the spectrometer over the energy range of interest. They discuss the efficiency and resolution of the spectrometer using propane as an operating fluid in the bubble chamber.

  7. Catalytic dehydrogenation of propane and isobutane in hydrogen permselective membrane reactors

    SciTech Connect

    Collins, J.P.; Schwartz, R.W.; Sehgal, R.; Ward, T.L.

    1996-09-01

    The dehydrogenation of propane and isobutane was studied in hydrogen permselective packed bed membrane reactors and conventional packed bed reactors. Two different types of developmental membranes were investigated: sol-gel derived silica-based membranes and a pure palladium thin film supported by a porous ceramic substrate. The palladium membranes deactivated and eventually failed when exposed to both isobutane and propane dehydrogenation temperatures above 773 K. Moderate improvements in propylene and isobutylene yields were obtained with the silica-based membrane reactors. An isobutylene yield of 48 mole percent was obtained at a liquid hourly space velocity (LHSV) of 1.8 and temperature of 798 K compared to a yield of 39 percent in a conventional reactor operated with the same flow rate. Similar improvements in propylene yield were obtained when the silica-based membranes were tested in propane dehydrogenation experiments. There was no significant difference in the reaction selectivities for the desired olefin products when the membrane and conventional reactors were operated with the scone LHSV However, for a constant value of the olefin yield, the membrane reactors had a higher reaction selectivity since the desired yield was achieved at a higher LHSV where there was less time for side products to form. Catalyst deactivation rates were generally greater in the membrane reactors, especially when the reactors were operated with high hydrogen removal rates at temperatures of 773 K and above.

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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 §...

  13. 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 §...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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 §...

  19. 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 §...

  20. 46 CFR 153.217 - Access to enclosed spaces and dedicated ballast tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Access to enclosed spaces and dedicated ballast tanks... and Equipment General Vessel Requirements § 153.217 Access to enclosed spaces and dedicated ballast tanks. An access opening to an enclosed space or a dedicated ballast tank must meet the requirements...

  1. 46 CFR 153.217 - Access to enclosed spaces and dedicated ballast tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Access to enclosed spaces and dedicated ballast tanks... and Equipment General Vessel Requirements § 153.217 Access to enclosed spaces and dedicated ballast tanks. An access opening to an enclosed space or a dedicated ballast tank must meet the requirements...

  2. 33 CFR 157.210 - Approved 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 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 §...

  3. 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...

  4. 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.

  5. 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. PMID:16259103

  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. Investigation of statistical iterative reconstruction for dedicated breast CT

    NASA Astrophysics Data System (ADS)

    Makeev, Andrey; Das, Mini; Glick, Stephen J.

    2012-03-01

    Dedicated breast CT has great potential for improving the detection and diagnosis of breast cancer. In this study, statistical iterative reconstruction with a penalized likelihood objective function and a Huber prior are investigated for use with breast CT. This prior has two free parameters, the penalty weight and the edgepreservation threshold, that need to be evaluated to determine those values that give optimal performance. Computer simulations with breast-like phantoms were used to study these parameters using various figuresof- merit that relate to performance in detecting microcalcifications. Results suggested that a narrow range of Huber prior parameters give optimal performance. Furthermore, iterative reconstruction provided improved performance measures as compared to conventional filtered back-projection.

  8. Dedicated extremity MR imaging of the foot and ankle.

    PubMed

    Hottya, G A; Péterfy, C G; Uffmann, M; Häckl, F O; LeHir, P; Rédei, J; Gindele, A U; Dion, E; Genant, H K

    2000-01-01

    The purpose of this review is to provide illustrative examples of diseases of the foot and ankle when imaged with a low-field MR imaging system. A retrospective review of 268 foot and ankle examinations, performed in our institution within the past 3 years with a 0.2-T (Artoscan Esaote, Genoa, Italy) dedicated extremity MR system was done. Additionally, illustrative comparison with conventional radiography and high-field MR imaging is presented in patients in whom these examinations were also performed. Although motion artifact limited the value of a few studies, in the majority of examinations low-field MR imaging provided diagnostic image quality for the full spectrum of disorders affecting the foot and ankle and seemed to be a feasible alternative to high-field MR imaging in establishing an accurate diagnosis.

  9. 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.

  10. 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.

  11. 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.

  12. 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. PMID:26492580

  13. [Chemical libraries dedicated to protein-protein interactions].

    PubMed

    Sperandio, Olivier; Villoutreix, Bruno O; Morelli, Xavier; Roche, Philippe

    2015-03-01

    The identification of complete networks of protein-protein interactions (PPI) within a cell has contributed to major breakthroughs in understanding biological pathways, host-pathogen interactions and cancer development. As a consequence, PPI have emerged as a new class of promising therapeutic targets. However, they are still considered as a challenging class of targets for drug discovery programs. Recent successes have allowed the characterization of structural and physicochemical properties of protein-protein interfaces leading to a better understanding of how they can be disrupted with small molecule compounds. In addition, characterization of the profiles of PPI inhibitors has allowed the development of PPI-focused libraries. In this review, we present the current efforts at developing chemical libraries dedicated to these innovative targets.

  14. 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.

  15. 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.

  16. Experience with the CSPAD during dedicated detector runs at LCLS

    NASA Astrophysics Data System (ADS)

    Carini, G. A.; Boutet, S.; Chollet, M.; Dragone, A.; Haller, G.; Hart, P. A.; Herrmann, S. C.; Kenney, C. J.; Koglin, J.; Messerschmidt, M.; Nelson, S.; Pines, J.; Robert, A.; Song, S.; Thayer, J. B.; Williams, G. J.; Zhu, D.

    2014-03-01

    In-house developed cameras and other commercial detectors are typically tested with x-ray tubes and at synchrotron beamlines before being deployed and used for science experiments. In a prototyping phase, this is needed to understand and characterize the behavior of the detector. In a more advanced development phase, measurements with x-rays are required to characterize and calibrate the camera. Tests at synchrotron beamlines in actual experimental conditions are indeed a valuable source for detector developers. However, when all photons arrive at once, as for FELs, the response of the detector can be very different from that obtained with a synchrotron beam which behaves more like a CW (continuous) source. This behavior was already observed during users runs at LCLS and recently investigated during dedicated detector beamtime. The linearity of the response of the Cornell-SLAC Pixel Array Detector (CSPAD) was investigated. Results are presented and discussed.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. Features of propane conversion in the presence of SmVO3 and SmVO4

    NASA Astrophysics Data System (ADS)

    Markova, E. B.; Lyadov, A. S.; Kurilkin, V. V.

    2016-09-01

    Features of propane conversion in the presence of samarium vanadite and samarium vanadate, both produced via solid-phase synthesis, are studied. It is shown that SmVO3 catalyzes mainly the propane cracking process to form methane and ethylene, while SmVO4 equally accelerates both cracking and the dehydrogenation of propane. Based on the results from catalytic experiments, energies of activation are calculated for the thermal cracking of propane (104 kJ/mol) and the conversion of propane in the presence of SmVO3 (39 kJ/mol) and SmVO4 (42 kJ/mol). The thermal stability of SmVO4 in a hydrogen atmosphere is studied via temperature-programmed reduction, while SmVO3 stability in an oxidizing environment is studied by DTA. Energies of activation for the reduction of SmVO4 (75 kJ/mol) and the oxidation of SmVO3 (244 kJ/mol) are calculated using the Kissinger method.

  3. 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.

  4. The Effects of Mountain Lee Waves on the Transport of Liquid Propane-Generated Ice Crystals.

    NASA Astrophysics Data System (ADS)

    Reynolds, David W.

    1996-09-01

    A combination of rawinsonde balloon ascent rates, low-elevation aircraft, and ground-based tracer sampling measurements are presented. These data indicate that mountain-induced gravity waves have a significant impact on the transport of ice crystals produced by the release of liquid propane from high-altitude dispensers along the crest of the northern Sierra Nevada in California. Special rawinsonde launches were made just downwind of the main Sierra Nevada crest. Balloon ascent rates show a very well defined mountain lee wave present during most precipitation events. Strong descent to the lee of the Sierra will thus have a detrimental effect on the growth of particles generated on the crest. The tracer SF6 (sulfur hexaflouride) is used to simulate the transport and dispersion of propane-generated ice crystals. Sulfur hexaflouride was released from two propane dispenser sites as a proxy for seeded ice crystals. Aircraft measurements of SF6 indicated that at the normal flight altitudes of 2500 m over the downwind valley and 2800 m over the downwind ridge the aircraft was flying near the top of the plumes. When the aircraft was able to fly below cloud base, near the release altitude of 2200 m, substantial SF6 was observed. The lower portion of the plume was also observed to descend into the valley some 700 m below the release altitude. A simple two-dimensional model is used to determine the impact that these gravity waves have on particle trajectories. Model output is presented for one well-documented seeding case to determine how well such models might be used operationally to predict particle trajectories downwind of the Sierra.

  5. The physical properties of the blast wave produced by a stoichiometric propane/oxygen explosion

    NASA Astrophysics Data System (ADS)

    Dewey, M. C.; Dewey, J. M.

    2014-07-01

    The trajectory of the primary shock produced by the explosion of a nominal 18.14 t (20 tn) hemispherical propane/oxygen charge was analysed previously to provide the physical properties immediately behind the shock, but gave no information about the time-resolved properties throughout the blast wave. The present study maps all the physical properties of the wave throughout and beyond the positive durations for a range of distances from about 1.6-18 m scaled to a 1 kg charge at NTP. The physical properties were calculated using a hydro-code to simulate the flow field produced by a spherical piston moving with a specific trajectory. This technique has been used extensively to determine the physical properties of blast waves from a variety of sources for which the piston path was determined by high-speed photography of smoke tracers established close to the charges immediately before detonation. In the case of the propane/oxygen explosion, smoke tracer data were not available to determine the trajectory of the spherical piston. An arbitrary piston path was used and its trajectory iteratively adjusted until it produced a blast wave with a primary shock whose trajectory exactly matched the measured trajectory from the propane/oxygen explosion. Throughout the studied flow field the time histories of hydrostatic pressure, density and particle velocity are well described by fits to the modified Friedlander equation. The properties are presented as functions of scaled radius and are compared with the properties of the blast wave from a 1 kg TNT surface burst explosion, and with other measurements of the same explosion.

  6. The physical properties of the blast wave produced by a stoichiometric propane/oxygen explosion

    NASA Astrophysics Data System (ADS)

    Dewey, M. C.; Dewey, J. M.

    2014-11-01

    The trajectory of the primary shock produced by the explosion of a nominal 18.14 t (20 tn) hemispherical propane/oxygen charge was analysed previously to provide the physical properties immediately behind the shock, but gave no information about the time-resolved properties throughout the blast wave. The present study maps all the physical properties of the wave throughout and beyond the positive durations for a range of distances from about 1.6-18 m scaled to a 1 kg charge at NTP. The physical properties were calculated using a hydro-code to simulate the flow field produced by a spherical piston moving with a specific trajectory. This technique has been used extensively to determine the physical properties of blast waves from a variety of sources for which the piston path was determined by high-speed photography of smoke tracers established close to the charges immediately before detonation. In the case of the propane/oxygen explosion, smoke tracer data were not available to determine the trajectory of the spherical piston. An arbitrary piston path was used and its trajectory iteratively adjusted until it produced a blast wave with a primary shock whose trajectory exactly matched the measured trajectory from the propane/oxygen explosion. Throughout the studied flow field the time histories of hydrostatic pressure, density and particle velocity are well described by fits to the modified Friedlander equation. The properties are presented as functions of scaled radius and are compared with the properties of the blast wave from a 1 kg TNT surface burst explosion, and with other measurements of the same explosion.

  7. 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.

  8. Propane-1,2-di­ammonium chromate(VI)

    PubMed Central

    Trabelsi, Sonia; Essid, Manel; Roisnel, Thierry; Rzaigui, Mohamed; Marouani, Houda

    2014-01-01

    In the title mol­ecular salt, (C3H12N2)[CrO4], each chromate anion accepts six N—H⋯O and C—H⋯O hydrogen bonds from nearby propane-1,2-di­ammonium cations. Three of the four O atoms of the chromate anion accept these bonds; the remaining Cr—O bond length is notably shorter than the others. In the crystal, the anions and cations stack in layers lying parallel to (100): the hydrogen-bonding pattern leads to a three-dimensional network. PMID:24764949

  9. 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.

  10. 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.

  11. Carbon nanotubes and other fullerene nanocrystals in domestic propane and natural gas combustion streams.

    PubMed

    Bang, J J; Guerrero, P A; Lopez, D A; Murr, L E; Esquivel, E V

    2004-09-01

    Carbon nanotubes and other aggregated fullerene-related multi-layer shell structures have been collected in propane and natural gas flame emissions from domestic cooking stoves and observed by transmission electron microscopy. Some aggregated nanoparticles collected on 3 mm electron microscope grids by thermal precipitation were mostly multi-walled nanotubes; many tangled and distorted, and aggregated with other closed-concentric, multi-shell forms. Such clean-burning regimes may be major contributors to complex particulate matter in indoor and outdoor air.

  12. 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

  13. 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

  14. Temporal subtraction contrast-enhanced dedicated breast CT.

    PubMed

    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

  15. 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

  16. Conceptual Design of a Dedicated SAXS Beamline at NSRRC

    NASA Astrophysics Data System (ADS)

    Liu, D. G.; Tseng, P. C.; Tsang, K. L.; Jeng, U.; Chang, C. H.; Fung, H. S.; Liu, C. Y.; Chung, S. C.; Tang, M. T.; Song, Y. F.; Liang, K. S.

    2007-01-01

    A dedicated small-angle X-ray scattering (SAXS) beamline using a new X-ray source generated by an In-Acromat superconducting wiggler (IASW6) insertion device is under construction at the National Synchrotron Radiation Research Center (NSRRC). The IASW6 with peak magnetic field of 3.1 T, magnet period of 6.1 cm, and total length of 96 cm, can provide a photon flux ˜ 1012 - 1013photons/s/0.1%bw in the energy range of 5 - 23 keV. Taking the central 0.2 mard horizontal radiation fan from the source with a beam divergence of 200 and 392 μrad in the vertical and horizontal directions, respectively, the dedicated SAXS beamline is oriented for nano to meso-structural research in soft matter, including liquid crystals, macromolecular solutions, polymers, as well as in nanoparticles, ceramic, and alloys. The SAXS beamline adopts the design of the double-monochromator used in the beamline SIYBLS at ALS, which integrates a Si(111) double crystal monochromator (DCM) and a Mo/B4C double multilayer monochromator (DMM) into one cradle for fast exchange between the two monochrmators. Equipped with a collimating mirror (CM) and a toroidal focusing mirror (FM) with 1:1 focusing ratio, this beamline provides two types of SAXS measurements: high-Q resolution and high flux, by using either the DCM or DMM. The SAXS beamline also provides energy scan with an energy resolution from 1 to 10 eV for anomalous SAXS (ASAXS) measurements. A specially coated reflecting mirror is also installed after FM to provide a suitable photon beam for grazing incident SAXS of liquid surfaces. Ray tracing simulation results show that at 8 keV and with DCM, a high quality photon beam of beam size (0.5 mm) and beam divergence (± 50 μrad) with a flux of ˜ 1011 photons/s can be obtained for high-Q resolution SAXS measurement. The photon flux can be increased by one order of magnitude when the DMM is used; however, the beam size and divergence are both slightly increased.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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. PMID:24999493

  7. AMYPdb: A database dedicated to amyloid precursor proteins

    PubMed Central

    Pawlicki, Sandrine; Le Béchec, Antony; Delamarche, Christian

    2008-01-01

    Background Misfolding and aggregation of proteins into ordered fibrillar structures is associated with a number of severe pathologies, including Alzheimer's disease, prion diseases, and type II diabetes. The rapid accumulation of knowledge about the sequences and structures of these proteins allows using of in silico methods to investigate the molecular mechanisms of their abnormal conformational changes and assembly. However, such an approach requires the collection of accurate data, which are inconveniently dispersed among several generalist databases. Results We therefore created a free online knowledge database (AMYPdb) dedicated to amyloid precursor proteins and we have performed large scale sequence analysis of the included data. Currently, AMYPdb integrates data on 31 families, including 1,705 proteins from nearly 600 organisms. It displays links to more than 2,300 bibliographic references and 1,200 3D-structures. A Wiki system is available to insert data into the database, providing a sharing and collaboration environment. We generated and analyzed 3,621 amino acid sequence patterns, reporting highly specific patterns for each amyloid family, along with patterns likely to be involved in protein misfolding and aggregation. Conclusion AMYPdb is a comprehensive online database aiming at the centralization of bioinformatic data regarding all amyloid proteins and their precursors. Our sequence pattern discovery and analysis approach unveiled protein regions of significant interest. AMYPdb is freely accessible [1]. PMID:18544157

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. Effect of bromine and chlorine positioning in the induction of renal and testicular toxicity by halogenated propanes.

    PubMed

    Låg, M; Søderlund, E J; Omichinski, J G; Brunborg, G; Holme, J A; Dahl, J E; Nelson, S D; Dybing, E

    1991-01-01

    A series of halogenated propanes were studied for renal and testicular necrogenic effects in the rat and correlated to their ability to induce in vivo renal and testicular DNA damage and in vitro testicular DNA damage. 1,2-Dibromo-3-chloropropane (DBCP) and 1,2,3-tribromopropane were most potent in causing organ damage in both kidney and testes. Extensive necrosis was evident at 85 mumol/kg in kidney and at 170 mumol/kg in testis. The dibromomonochlorinated analogue 1,3-dibromo-2-chloropropane was less organ toxic than DBCP and 1,2,3-tribromopropane, but induced more organ damage than the dichloromonobrominated analogues 1-bromo-2,3-dichloropropane and 1,3-dichloro-2-bromopropane. Dihalogenated propanes were even less necrogenic. These observed differences in toxic potency between the halogenated propanes could not be explained by relative differences in tissue concentrations. The ability of the halogenated propanes to induce DNA damage in vivo correlated well with their ability to induce organ damage. However, DNA damage occurred at lower doses and at a shorter period of exposure than organ necrosis. This indicates that DNA damage might be an initial event in the development of organ necrosis by halogenated propanes in general. Further, testicular DNA damage induced by the halogenated propanes in vivo correlated well with the DNA damage observed in isolated testicular cells in vitro, showing that toxicity was due to in situ activation. The numbers, positions, and the types of halogen substituents appear to be important determinants in causing DNA damage and necrogenic effects.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1793801

  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. Effects of Propane/Natural Gas Blended Fuels on Gas Turbine Pollutant Emissions

    SciTech Connect

    Straub, D.L.; Ferguson, D.H.; Casleton, K.H.; Richards, G.A.

    2007-03-01

    Liquefied natural gas (LNG) imports to the U.S. are expected to grow significantly over the next 10-15 years. Likewise, it is expected that changes to the domestic gas supply may also introduce changes in natural gas composition. As a result of these anticipated changes, the composition of fuel sources may vary significantly from conventional domestic natural gas supplies. This paper will examine the effects of fuel variability on pollutant emissions for premixed gas turbine conditions. The experimental data presented in this paper have been collected from a pressurized single injector combustion test rig at the National Energy Technology Laboratory (NETL). The tests are conducted at 7.5 atm with a 588 K air preheat. A propane blending facility is used to vary the Wobbe Index of the site natural gas. The results indicate that propane addition of about five (vol.) percent does not lead to a significant change in the observed NOx or CO emissions. These results are different from data collected on some engine applications and potential reasons for these differences will be described.

  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. Survey of microbial oxygenases: Trichloroethylene degradation by propane-oxidizing bacteria

    SciTech Connect

    Wackett, L.P.; Brusseau, G.A.; Householder, S.R.; Hanson, R.S. )

    1989-11-01

    Microorganisms that biosynthesize broad-specificity oxygenases to initiate metabolism of linear and branched-chain alkanes, nitroalkanes, cyclic ketones, alkenoic acids, and chromenes were surveyed for the ability to biodegrade trichloroethylene (TCE). The results indicated that TCE oxidation is not a common property of broad-specificity microbial oxygenases. Bacteria that contained nitropropane dioxygenase, cyclohexanone monooxygenase, cytochrome P-450 monooxygenases, 4-methoxybenzoate monooxygenase, and hexane monooxygenase did not degrade TCE. However, one new unique class of microorganisms removed TCE from incubation mixtures. Five Mycobacterium strains that were grown on propane as the sole source of carbon and energy degraded TCE. Mycobacterium vaccae JOB5 degraded TCE more rapidly and to a greater extent than the four other propane-oxidizing bacteria. At a starting concentration of 20 {mu}M, it removed up to 99% of the TCE in 24 h. M. vaccae JOB5 also biodegraded 1,1-dichloroethylene, trans-1,2-dichloroethylene, cis-1,2-dichloroethylene, and vinyl chloride.

  17. Rotational reorientation dynamics of Aerosol-OT reverse micelles formed in near-critical propane

    SciTech Connect

    Heitz, M.P.; Bright, F.V.

    1996-06-01

    The rotational reorientation kinetics of two fluorescent solutes (rhodamine 6G, R6G, and rhodamine 101, R101) have been determined in sodium bis(2-ethylhexyl) sulfosuccinate (Aerosol-OT, AOT) reverse micelles formed in liquid and near-critical propane. We show that the amount of water loading ([water]/[AOT], R), continuous phase density, and temperature all influence the solute rotational dynamics. In all cases, the decay of anisotropy data (i.e., frequency-dependent differential polarized phase angle and polarized modulation ratio) are well described by a bi-exponential decay law. We find that the faster rotational correlation times are similar to but slightly less than the values predicted for an individual AOT reverse micelle rotating in propane. The recovered rotational correlation times range from 200 to 500 ps depending on experimental conditions. This faster rotational process is explained in terms of lateral diffusion of the fluorophore along the water/headgroup interfacial region within the reverse micelle. The recovered values for the slower rotational correlation times range from 7 to 18 ns. These larger rotational reorientation times are assigned to varying micelle-micelle (i.e., tail-tail) interactions in the low-density, highly compressible fluid region. We also quantify the contribution of the reverse micellar {open_quotes}aggregate{close_quotes} to the total decay of anisotropy. {copyright} {ital 1996} {ital Society for Applied Spectroscopy}

  18. Effects of Propane/Natural Gas Blended Fuels on Gas Turbine Pollutant Emissions

    SciTech Connect

    D. Straub; D. Ferguson; K. Casleton; G. Richards

    2006-03-01

    U.S. natural gas composition is expected to be more variable in the future. Liquefied natural gas (LNG) imports to the U.S. are expected to grow significantly over the next 10-15 years. Unconventional gas supplies, like coal-bed methane, are also expected to grow. As a result of these anticipated changes, the composition of fuel sources may vary significantly from existing domestic natural gas supplies. To allow the greatest use of gas supplies, end-use equipment should be able to accommodate the widest possible gas composition. For this reason, the effect of gas composition on combustion behavior is of interest. This paper will examine the effects of fuel variability on pollutant emissions for premixed gas turbine conditions. The experimental data presented in this paper have been collected from a pressurized single injector combustion test rig at the National Energy Technology Laboratory (NETL). The tests are conducted at 7.5 atm with a 589K air preheat. A propane blending facility is used to vary the Wobbe Index of the site natural gas. The results indicate that propane addition of about five (vol.) percent does not lead to a significant change in the observed NOx emissions. These results vary from data reported in the literature for some engine applications and potential reasons for these differences are discussed.

  19. Survey of microbial oxygenases: trichloroethylene degradation by propane-oxidizing bacteria.

    PubMed Central

    Wackett, L P; Brusseau, G A; Householder, S R; Hanson, R S

    1989-01-01

    Microorganisms that biosynthesize broad-specificity oxygenases to initiate metabolism of linear and branched-chain alkanes, nitroalkanes, cyclic ketones, alkenoic acids, and chromenes were surveyed for the ability to biodegrade trichloroethylene (TCE). The results indicated that TCE oxidation is not a common property of broad-specificity microbial oxygenases. Bacteria that contained nitropropane dioxygenase, cyclohexanone monooxygenase, cytochrome P-450 monooxygenases, 4-methoxybenzoate monooxygenase, and hexane monooxygenase did not degrade TCE. However, one new unique class of microorganisms removed TCE from incubation mixtures. Five Mycobacterium strains that were grown on propane as the sole source of carbon and energy degraded TCE. Mycobacterium vaccae JOB5 degraded TCE more rapidly and to a greater extent than the four other propane-oxidizing bacteria. At a starting concentration of 20 microM, it removed up to 99% of the TCE in 24 h. M. vaccae JOB5 also biodegraded 1,1-dichloroethylene, trans-1,2-dichloroethylene, cis-1,2-dichloroethylene, and vinyl chloride. PMID:2624467

  20. 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

  1. 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.

  2. 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).

  3. Role of tetrachloromethane as a gas-phase additive in the oxidative dehydrogenation of propane over cerium oxide

    SciTech Connect

    Sugiyama, Shigeru; Iizuka, Y.; Nitta, E.; Hayashi, H.; Moffat, J.B.

    2000-01-01

    In the absence of tetrachloromethane (TCM) carbon dioxide is the principal product formed in the oxidation of propane on ceria. The introduction of small partial pressures of TCM increases the conversion of propane with selectivities to propene up to 80%. Except under special circumstances no evidence of chlorinated species from TCM is found in the bulk structure while the surface region is shown to contain chlorine, although its form is not known. The enhancement of conversion and selectivity to propene is shown to be dependent upon the presence of chlorine, in whatever form, in the surface region of the catalyst.

  4. 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.

  5. 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. PMID:24500660

  6. [Psychological aspects of cancer Information dedicated to patients and relatives].

    PubMed

    Machavoine, Jean-Luc; Bonnet, Valérie; Leichtnam-Dugarin, Line; Dolbeault, Sylvie; Marx, Eliane; Dauchy, Sarah; Flahault, Cécile; Bendrihen, Nicolas; Pelicier, Nicole; Syp, Laurence; Pérennec, Marie-Estelle; Dilhuydy, Jean-Marie; Marx, Gilles; Chaussumier, Caroline; Brusco, Sylvie; Carretier, Julien; Delavigne, Valérie; Fervers, Béatrice; Philip, Thierry

    2007-02-01

    In response to the evolution of the information-seeking behaviour of patients and concerns from health professionals regarding cancer patient information, the French National Federation of Comprehensive Cancer Centres (FNCLCC) introduced, in 1998, an information and education program dedicated to patients and relatives, the SOR SAVOIR PATIENT program (SSP). The methodology of this program adheres to established quality criteria regarding the elaboration of patient information. Cancer patient information, developed in this program, is based on clinical practice guidelines produced by the FNCLCC and the twenty French cancer centres, the National League against Cancer, The National Cancer Institute, the French Hospital Federation, the National Oncology Federation of Regional and University Hospitals, the French Oncology Federation of General Hospitals, many learned societies, as well as an active participation of patients, former patients and caregivers. The information and dialogue handbook SOR SAVOIR PATIENT Vivre pendant et après un cancer reporting on the psychological aspects of cancer was worked out and published on the Web in 2005. The guide aims to provide cancer patients with support and advice about the psychological impact of the disease. It provides information on the possible personal consequences of the disease and treatments, in every domain: psychological, emotional, interpersonal, familial or professional. Patients are also advised of the emotional challenges associated with cancer, of the support they may expect at every stage of the disease, from diagnosis to treatment, and of psychological outcome after the disease is over. The document also provides healthcare professionals with a valuable, concise source of validated information on the psychological aspects of cancer, thus facilitating communication between carers and patients. Information provided in the present article has been selected from the information and dialogue handbook SOR SAVOIR

  7. Identification of Methane, Ethane, and Propane Oxidizing Bacteria at Marine Hydrocarbon Seeps by Stable Isotope Probing

    NASA Astrophysics Data System (ADS)

    Redmond, M.; Ding, H.; Friedrich, M. W.; Valentine, D. L.

    2008-12-01

    Hydrocarbon seeps emit substantial amounts of oil and natural gas into the marine environment, where they can be oxidized by microorganisms in the sediment and water column. Here, we used stable isotope probing of DNA and lipid biomarkers to identify the microorganisms actively consuming 13C-labeled natural gas compounds in seep sediment samples. Surface sediment was collected from the Coal Oil Point seep field (offshore Santa Barbara, California, USA) and incubated under aerobic conditions with 13C labeled methane, ethane, or propane for up to 37 days, with sediment sub-samples taken at 3-4 intermediate time points. DNA was extracted from sediment and separated by CsCl density gradient centrifugation. The microbial community in each fraction was profiled using T-RFLP, and bacterial 16S rRNA gene clone libraries were constructed from un-incubated hydrocarbon seep sediment and selected isotopically 'heavy' (13C) and 'light' (12C) gradient fractions from ethane incubations. All clone libraries were dominated by sequences from members of the family Rhodobacteraceae (>25% of sequences) and a diverse group of Gammaproteobacteria, including sequences related to those of methylotrophs and to those of bacteria known to consume the longer-chain alkanes present in crude oil. After 14 days of incubation, the relative abundance of Rhodobacteraceae was higher in 'heavy' fractions from the 13C-ethane incubation than in 'light' fractions, suggesting incorporation of 13C label. The Rhodobacteraceae are very diverse metabolically, but have often been observed in abundance in oil contaminated seawater. Several members of this group have been shown to oxidize longer chain alkanes (C10 or higher), but none have been previously linked to the consumption of the gaseous alkanes ethane, propane, and butane. For the final time point, 13C content of phospholipid fatty acids (PLFA) were also analyzed, showing substantial incorporation of 13C over 37 days. In the methane incubation

  8. Design study of a cardiac-dedicated PET system

    NASA Astrophysics Data System (ADS)

    Peng, Hao

    2015-04-01

    The work studies the feasibility of developing a cardiac-dedicated PET system using Monte Carlo simulation tools. The proposed system comprises a dual-panel geometry and both panels utilize fine crystal elements (~2-3 mm) to help improve high spatial resolution. The system performances were studied with respect to photon detection sensitivity, count-rate performances, spatial resolution, depth-of-interaction (DOI) capability, and potential contrast recovery improvement due to time-of-flight (TOF). For a 2:3 dual panel configuration (front panel: 24.0×18.0 cm2 and back panel: 36.0×27.0 cm2), the system is able to achieve a peak photon sensitivity of ~13.0% at the location of the heart. For count-rate performances, the system is able to yield a continuous increase of noise equivalent count rate (NECR) as a function of the total activity of radiotracers between 10 mCi and 50 mCi. When crystal elements of 2×2×20 cm3 are deployed in the front panel and crystal elements of 3×3×20 cm3 are deployed in the back panel, the proposed system is not only able to revolve 2 mm diameter spheres in the image slices parallel to the panels but also demonstrates good resolution uniformity of less than 5%. On the other hand, significant resolution degradation occurs in the direction perpendicular to the panels due to the following two factors: limited angular coverage and finite DOI resolution. Such degradation was quantitatively analyzed for five different DOI resolutions (0 mm, 2.5 mm, 5 mm, 10 mm and 20 mm), as well as three different crystal configurations. Finally, the contrast study with a heart-like phantom (comprising lumen, aortic wall, myocardium and small lesions) indicates that TOF capability (time resolution: 250-500 ps) does not significantly improve image quality and lesion detectability, in terms of contrast-to-noise ratio (CNR).

  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. 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

  12. 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... Procedure for Dedicated Clean Ballast Tanks Operations 1. Source. The example procedure for dedicated clean... Protocol. 2. Example Procedure. Dedicated clean ballast tanks operational procedure: (a) Before arrival...

  13. 33 CFR Appendix D to Part 157 - Example of a Procedure for Dedicated Clean Ballast Tanks Operations

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Dedicated Clean Ballast Tanks Operations D Appendix D to Part 157 Navigation and Navigable Waters COAST... Procedure for Dedicated Clean Ballast Tanks Operations 1. Source. The example procedure for dedicated clean... Protocol. 2. Example Procedure. Dedicated clean ballast tanks operational procedure: (a) Before arrival...

  14. 33 CFR Appendix D to Part 157 - Example of a Procedure for Dedicated Clean Ballast Tanks Operations

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Dedicated Clean Ballast Tanks Operations D Appendix D to Part 157 Navigation and Navigable Waters COAST... Procedure for Dedicated Clean Ballast Tanks Operations 1. Source. The example procedure for dedicated clean... Protocol. 2. Example Procedure. Dedicated clean ballast tanks operational procedure: (a) Before arrival...

  15. 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).

  16. Modification of Wood Pellets and Propane Co-firing in a Magnetic Field

    NASA Astrophysics Data System (ADS)

    Barmina, Inese; Zake, Maija; Krishko, Vera; Gedrovics, Martins

    2010-01-01

    When burning fossil fuels and renewable energy resources, greenhouse emissions (GHG) are emitted into the atmosphere. One of the options to reduce GHG emissions is to apply a magnetic field. The effect of a gradient magnetic field on the gasification of renewable fuel and the combustion of volatiles by applying the field to the bottom part of the swirl flame with recirculation is studied for the conditions of field-enhanced reverse heat and mass transfer of paramagnetic flame species up to the layer of wood pellets. The aim of research to investigate the magnetic field effect on swirling flame dynamics for the conditions of self-sustaining wood fuel combustion and by cofiring with propane flow.

  17. A metal-organic framework-based splitter for separating propylene from propane.

    PubMed

    Cadiau, A; Adil, K; Bhatt, P M; Belmabkhout, Y; Eddaoudi, M

    2016-07-01

    The chemical industry is dependent on the olefin/paraffin separation, which is mainly accomplished by using energy-intensive processes. We report the use of reticular chemistry for the fabrication of a chemically stable fluorinated metal-organic framework (MOF) material (NbOFFIVE-1-Ni, also referred to as KAUST-7). The bridging of Ni(II)-pyrazine square-grid layers with (NbOF5)(2-) pillars afforded the construction of a three-dimensional MOF, enclosing a periodic array of fluoride anions in contracted square-shaped channels. The judiciously selected bulkier (NbOF5)(2-) caused the looked-for hindrance of the previously free-rotating pyrazine moieties, delimiting the pore system and dictating the pore aperture size and its maximum opening. The restricted MOF window resulted in the selective molecular exclusion of propane from propylene at atmospheric pressure, as evidenced through multiple cyclic mixed-gas adsorption and calorimetric studies. PMID:27387945

  18. Effect of superficial velocity on vaporization pressure drop with propane in horizontal circular tube

    NASA Astrophysics Data System (ADS)

    Novianto, S.; Pamitran, A. S.; Nasruddin, Alhamid, M. I.

    2016-06-01

    Due to its friendly effect on the environment, natural refrigerants could be the best alternative refrigerant to replace conventional refrigerants. The present study was devoted to the effect of superficial velocity on vaporization pressure drop with propane in a horizontal circular tube with an inner diameter of 7.6 mm. The experiments were conditioned with 4 to 10 °C for saturation temperature, 9 to 20 kW/m2 for heat flux, and 250 to 380 kg/m2s for mass flux. It is shown here that increased heat flux may result in increasing vapor superficial velocity, and then increasing pressure drop. The present experimental results were evaluated with some existing correlations of pressure drop. The best prediction was evaluated by Lockhart-Martinelli (1949) with MARD 25.7%. In order to observe the experimental flow pattern, the present results were also mapped on the Wang flow pattern map.

  19. 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. PMID:25138580

  20. 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.

  1. Autothermal reforming of propane over Mg-Al hydrotalcite-like catalysts.

    PubMed

    Lim, You-Soon; Park, Nam-Cook; Shin, Jae-Soon; Kim, Jong-Ho; Moon, Dong-Ju; Kim, Young-Chul

    2008-10-01

    The performance of hydrotalcite-like catalysts in propane autothermal reforming for hydrogen production was studied in fixed-bed flow reactor. Hydrotalcite-like catalysts were synthesized by coprecipitation and modified co-precipitation by the impregnation method and those were promoted by the addition of noble metals. Reaction test results indicated that hydrotalcite-like catalysts of modified method were showed higher H2-yield than co-precipitation method because surface Ni particles of catalysts by modified method were more abundant. When added noble metals, the activity was enhanced because the size of nickel particles was decreased and degree of dispersion was increased. Also the carbon deposit is low after the reaction. When solvent of solution was changed, activity was increased. It is because degree of dispersion was increased.

  2. 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.

  3. Flamelet modelling of propane--air chemistry in turbulent non-premixed combustion

    SciTech Connect

    Askari-Sardhai, A.; Liew, S.K.; Moss, J.B.

    1985-01-01

    This short paper describes the application of the flamelet modelling approach to the prediction of the species concentration field in a turbulent propane-air flame. The structure of the laminar flamelet, the microscopic element in the model, is computed using a semi-global expression for fuel disappearance in conjunction with an established reaction scheme for the oxidation of CO and H/sub 2/. Detailed predictions for a turbulent jet-flame are compared with available experimental data. The significant measure of non-equilibrium which the flamelet introduces leads to substantial improvements in the prediction of CO, H/sub 2/, and C/sub 3/H/sub 8/ mass fractions in comparison with the simplest alternative model, that of full chemical equilibrium.

  4. Hydrothermal synthesis of new wolframite type trimetallic materials and their use in oxidative dehydrogenation of propane.

    PubMed

    Salamanca, Maurin; Licea, Yordy E; Echavarría, Adriana; Faro, Arnaldo C; Palacio, Luz A

    2009-11-01

    With the aim of obtaining materials with properties for use as catalysts, two new trimetallic oxides containing Co or Ni and Mo and W were synthesized by a hydrothermal method, using milder conditions than those normally used for wolframite type solids. They were characterized by X-ray diffraction, Fourier transformed infrared spectroscopy, laser Raman spectroscopy, temperature-programmed reduction and atomic absorption spectroscopy, indicating that pure wolframite phases were formed. The X-ray diffraction studies confirmed the formation of the structure in the monoclinic system with cell parameters similar to nickel tungsten wolframite. The laser Raman and infrared spectra showed differences among the samples, mainly due to the incorporation of molybdenum atoms in the wolframite structure. Incorporation of molybdenum in the catalysts improved catalytic activity for propane oxidative dehydrogenation, and lower reaction temperatures were required in order to obtain similar propene yields as in bimetallic tungsten wolframites.

  5. 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.

  6. Roaming mediated nonadiabatic dynamics in molecular hydrogen elimination from propane at 157 nm

    NASA Astrophysics Data System (ADS)

    Rauta, Akshaya Kumar; Maiti, Biswajit

    2016-09-01

    The photofragmentation dynamics study using Tully's fewest switches trajectory surface hopping calculations, based on MRCIS(6, 6)/6-31++G∗∗ potential energy surfaces, energy gradients and nonadiabatic couplings, reveals the occurrence of roaming mediated nonadiabatic pathways for the elimination of molecular hydrogen from propane at 157 nm. 1,2- and 1,3-molecular hydrogen eliminations, the minor dissociation channels, exclusively follow roaming (of partially dissociated H atom) mediated nonadiabatic pathway (S1 → S0) to the ground electronic state followed by an atomic hydrogen abstraction from another carbon atom in the ground singlet (S0) state. 1,1- and 2,2-molecular hydrogen eliminations on the other hand, the major dissociation processes, proceed either adiabatically in the first excited singlet (S1) electronic state or through the internal conversion S1 → S0 followed by direct two-body fragmentation in the ground singlet (S0) state, with equal probability.

  7. Numerical simulation of Jet-A combustion approximated by improved propane chemical kinetics

    NASA Technical Reports Server (NTRS)

    Ying, Shuh-Jing; Nguyen, Hung Lee

    1991-01-01

    Through the effort devoted to the chemical kinetics for propane air combustion, three mechanisms are developed. The full mechanism consists of 131 reactions. This mechanism is used as a guide for the evaluation of other mechanisms, but because of the long expected cpu time, it is not to be incorporated into the computer code KIVA-II for actual simulation. Through the sensitivity analysis, a reduced mechanism of 45 reactions is produced. But the calculated results from the 45 reaction mechanism are always low in temperature. Some efforts are devoted to correct this situation and details are included in this report. A simplified mechanism of reactions is successfully improved and computed results are compared with experimental data. Contour plots of physical parameters and species concentrations and results for emission indices of CO and NOx are presented.

  8. Vapor-liquid equilibria for the binary difluoromethane (R-32) + propane (R-290) mixture

    SciTech Connect

    Higashi, Y. . Dept. of Mechanical Engineering)

    1999-03-01

    The vapor-liquid equilibrium of the mixture composed of difluoromethane (R-32) and propane (R-290) was studied in the temperature range between 273.15 and 313.15 K. The experimental uncertainties of temperature, pressure, and composition measurements were estimated to be within [+-]10 mK, [+-]3 kPa, and [+-]0.4 mol%, respectively. Comparisons between the present data and available experimental data were made using the Helmholz free energy mixture model (HMM) adopted in the thermophysical properties program package, REFPOP 6.0, as a baseline. In addition, the existence of an azeotrope and the determination of new adjustable parameters for HMM for the R-32 + R-290 mixture are discussed.

  9. Vapor-liquid equilibria for the binary difluoromethane (R-32) + propane (R-290) mixture

    SciTech Connect

    Higashi, Y.

    1999-03-01

    The vapor-liquid equilibrium of the mixture composed of difluoromethane (R-32) and propane (R-290) was studied in the temperature range between 273.15 and 313.15 K. The experimental uncertainties of temperature, pressure, and composition measurements were estimated to be within {+-}10 mK, {+-}3 kPa, and {+-}0.4 mol%, respectively. Comparisons between the present data and available experimental data were made using the Helmholz free energy mixture model (HMM) adopted in the thermophysical properties program package, REFPOP 6.0, as a baseline. In addition, the existence of an azeotrope and the determination of new adjustable parameters for HMM for the R-32 + R-290 mixture are discussed.

  10. Gene structure and regulation of alkane monooxygenases in propane-utilizing Mycobacterium sp. TY-6 and Pseudonocardia sp. TY-7.

    PubMed

    Kotani, Tetsuya; Kawashima, Yui; Yurimoto, Hiroya; Kato, Nobuo; Sakai, Yasuyoshi

    2006-09-01

    Mycobacterium sp. TY-6 and Pseudonocardia sp. TY-7 were isolated from soil samples as propane-utilizing bacteria and were found to be able to utilize various gaseous and liquid n-alkanes as carbon and energy sources. One gene cluster, M-prmABCD, and two gene clusters, P-prm1ABCD and P-prm2ABCD, were cloned from the genomes of Mycobacterium sp. TY-6 and Pseudonocardia sp. TY-7, respectively. These gene clusters are homologous to the gene cluster encoding the multicomponent propane monooxygenase (prmABCD) of Gordonia sp. TY-5. The expression of prm gene clusters in Mycobacterium sp. TY-6 and Pseudonocardia sp. TY-7 was shown to be induced by gaseous n-alkanes (C2-C4) except methane, suggesting that the products of these genes are involved in gaseous n-alkane oxidation. Homologous genes for an alkane hydroxylase system (alk system) involved in liquid n-alkane oxidation were also cloned from the genomic DNA of Mycobacterium sp. TY-6. The alk gene cluster was transcribed in response to liquid n-alkanes (C11-C15). These results indicate that Mycobacterium sp. TY-6 has two distinct gene clusters for multicomponent monooxygenases involved in alkane oxidation. Whole-cell reactions revealed that propane is oxidized to 1-propanol through terminal oxidation in Mycobacterium sp. TY-6 and that propane is oxidized to 1-propanol and 2-propanol through both terminal and subterminal oxidations in Pseudonocardia sp. TY-7. This study reveals the diversity of propane metabolism present in microorganisms. PMID:17046531

  11. The effect of acoustics on an ethanol spray flame in a propane-fired pulse combustor

    SciTech Connect

    Dubey, R.K.; Black, D.L.; McQuay, M.Q.; Carvalho, J.A. Jr.

    1997-07-01

    The influence of an acoustic field on the combustion characteristics of a hydrogen-stabilized ethanol spray flame has been experimentally investigated using a phase-Doppler particle analyzer in a propane-fired, Rijke-tube, pulse combustor. The controlled sinusoidal acoustic field in the combustor had a sound pressure level of 155 dB and a frequency of 80 Hz. Experiments were performed to study the effect of oscillations on Sauter-mean and arithmetic-mean diameters, droplet velocity, and droplet number density for the present operating conditions of the Rijke-tube combustor. Similar measurements were also performed on a water spray in the propane-fired reactor to study the effect of the acoustic field on the atomization process for the nozzle type used. Spectral analysis of the droplet axial velocity component for the oscillating conditions revealed a dominant frequency equal to the frequency of the sinusoidal acoustic wave in the combustor. The Sauter-mean diameter of the ethanol spray decreased by 15%, on average, in the presence of the acoustic field because of enhanced evaporation, while the droplet arrival rate at the probe volume increased due to changes in the flame structure. Analysis of the measured size distributions indicated that under an oscillating flow there was a larger population of droplets in the diameter range of 3--20 {micro}m. Experiments conducted with the water spray indicated that the oscillations did affect droplet size distributions in the ethanol spray due to enhanced evaporation caused by the relocation of the flame front inside and around the spray cone.

  12. 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).

  13. [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.

  14. 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.

  15. Aerobic treatment of N-nitrosodimethylamine in a propane-fed membrane bioreactor.

    PubMed

    Hatzinger, Paul B; Condee, Charles; McClay, Kevin R; Paul Togna, A

    2011-01-01

    N-Nitrosodimethylamine (NDMA) is a suspected human carcinogen that has recently been detected in wastewater, groundwater and drinking water. Treatment of this compound to low part-per-trillion (ng/L) concentrations is required to mitigate cancer risk. Current treatment generally entails UV irradiation, which while effective, is also expensive. The objective of this research was to explore potential bioremediation strategies as alternatives for treating NDMA to ng/L concentrations. Batch studies revealed that the propanotroph Rhodococcus ruber ENV425 was capable of metabolizing NDMA from 8 μg/L to <2 ng/L after growth on propane, and that the strain produced metabolites that do not pose a significant risk at the concentrations generated (Fournier et al., 2009). A laboratory-scale membrane bioreactor (MBR) was subsequently constructed to evaluate the potential for long-term ex situ treatment of NDMA. The MBR was seeded with ENV425 and received propane as the primary growth substrate and oxygen as an electron acceptor. At an average influent NDMA concentration of 7.4 μg/L and a 28.5 h hydraulic residence time, the reactor effluent concentration was 3.0 ± 2.3 ng/L (>99.95% removal) over more than 70 days of operation. The addition of trichloroethene (TCE) to the reactor resulted in a significant increase in effluent NDMA concentrations, most likely due to cell toxicity from TCE-epoxide produced during its cometabolic oxidation by ENV425. The data suggest that an MBR system can be a viable treatment option for NDMA in groundwater provided that high concentrations of TCE are not present. PMID:20701948

  16. Flame Inhibition by Phosphorus-Containing Compounds in Lean and Rich Propane Flames

    SciTech Connect

    Curran, H; Korobeinichev, O P; Shvartsberg, V M; Shmakov, A G; Bolshova, T A; Jayaweera, T M; Melius, C F; Pitz, W J; Westbrook, C K

    2003-12-19

    Chemical inhibition of laminar propane flames by organophosphorus compounds has been studied experimentally, using a laboratory Mache Hebra nozzle burner and a flat flame burner with molecular beam mass spectrometry (MBMS), and with a computational flame model using a detailed chemical kinetic reaction mechanism. Both fuel-lean and fuel-rich propane flames were studied to examine the role of equivalence ratio in flame inhibition. The experiments examined a wide variety of organophosphorus compounds. We report on the experimental species flame profiles for tri-methyl phosphate (TMP) and compare them with the species flame profile results from modeling of TMP and di-methyl methyl phosphonate (DMMP). Both the experiments and kinetic modeling support and illustrate previous experimental studies in both premixed and non-premixed flames that inhibition efficiency is effectively the same for all of the organophosphorus compounds examined, independent of the molecular structure of the initial inhibitor molecule. The chemical inhibition is due to reactions involving the small P-bearing species HOPO{sub 2} and HOPO that are produced by the organophosphorus compounds (OPCs). The ratios of the HOPO{sub 2} and HOPO concentrations differ between the lean and rich flames, with HOPO{sub 2} dominant in lean flames while HOPO dominates in rich flames. The resulting HOPO{sub 2} and HOPO species profiles do not depend significantly on the initial source of the HOPO{sub 2} and HOPO and thus are relatively insensitive to the initial OPC inhibitor. A more generalized form of the original Twarowski mechanism for hydrocarbon radical recombination is developed to account for the results observed, and new theoretical values have been determined for heats of formation of the important P-containing species, using the BAC-G2 method.

  17. Third order optical nonlinearity and optical limiting studies of propane hydrazides

    NASA Astrophysics Data System (ADS)

    Naseema, K.; Manjunatha, K. B.; Sujith, K. V.; Umesh, G.; Kalluraya, Balakrishna; Rao, Vijayalakshmi

    2012-09-01

    Four hydrazones, 2-(4-isobutylphenyl)-N'-[phenylmethylene] propanehydrazide (P1), 2-(4-isobutylphenyl)-N'-[(4- tolyl)methylene] propane hydrazide (P2), 2-(4-isobutylphenyl)-N'-[1-(4- chlorophenyl)ethylidene] propanehydrazide (P3) and 2-(4-isobutylphenyl)-N'-[1-(4-Nitrrophenyl)ethylidene] propane hydrazide (P4) were synthesized and their third order nonlinear optical properties have been investigated using a single beam Z-scan technique with nanosecond laser pulses at 532 nm. The measurement on the compound-P1 is not reported as there is no detectable nonlinear response. Open aperture data of the other three compounds indicate two photon absorption at this wavelength. The nonlinear refractive index n2, nonlinear absorption coefficient β, magnitude of effective third order susceptibility χ(3), the second order hyperpolarizability γh and the coupling factor ρ have been estimated. The values obtained are comparable with the values obtained for 4-methoxy chalcone derivatives and dibenzylideneacetone derivatives. The experimentally determined values of β, n2, Re χ(3) and Im χ(3), γh and ρ of the compound-P4 are 1.42 cm/GW, -0.619 × 10-11 esu, -0.663 × 10-13 esu, 0.22 × 10-13 esu, 0.34 × 10-32 esu and 0.33 respectively. Further the compound-P4 exhibited the best optical power limiting behavior at 532 nm among the compounds studied. Our studies suggest that compounds P2, P3 and P4 are potential candidates for the optical device applications such as optical limiters and optical switches.

  18. 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.

  19. 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…

  20. 46 CFR 153.219 - Access to double bottom tanks serving as dedicated ballast tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Access to double bottom tanks serving as dedicated... MATERIALS Design and Equipment General Vessel Requirements § 153.219 Access to double bottom tanks serving... openings to double bottom tanks serving as dedicated ballast tanks must not be located within a...

  1. 46 CFR 153.219 - Access to double bottom tanks serving as dedicated ballast tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Access to double bottom tanks serving as dedicated... MATERIALS Design and Equipment General Vessel Requirements § 153.219 Access to double bottom tanks serving... openings to double bottom tanks serving as dedicated ballast tanks must not be located within a...

  2. 46 CFR 153.219 - Access to double bottom tanks serving as dedicated ballast tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Access to double bottom tanks serving as dedicated... MATERIALS Design and Equipment General Vessel Requirements § 153.219 Access to double bottom tanks serving... openings to double bottom tanks serving as dedicated ballast tanks must not be located within a...

  3. 46 CFR 153.219 - Access to double bottom tanks serving as dedicated ballast tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Access to double bottom tanks serving as dedicated... MATERIALS Design and Equipment General Vessel Requirements § 153.219 Access to double bottom tanks serving... openings to double bottom tanks serving as dedicated ballast tanks must not be located within a...

  4. 46 CFR 153.219 - Access to double bottom tanks serving as dedicated ballast tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Access to double bottom tanks serving as dedicated... MATERIALS Design and Equipment General Vessel Requirements § 153.219 Access to double bottom tanks serving... openings to double bottom tanks serving as dedicated ballast tanks must not be located within a...

  5. Bowtie filters for dedicated breast CT: Theory and computational implementation

    SciTech Connect

    Kontson, Kimberly Jennings, Robert J.

    2015-03-15

    Purpose: To design bowtie filters with improved properties for dedicated breast CT to improve image quality and reduce dose to the patient. Methods: The authors present three different bowtie filters designed for a cylindrical 14-cm diameter phantom with a uniform composition of 40/60 breast tissue, which vary in their design objectives and performance improvements. Bowtie design #1 is based on single material spectral matching and produces nearly uniform spectral shape for radiation incident upon the detector. Bowtie design #2 uses the idea of basis material decomposition to produce the same spectral shape and intensity at the detector, using two different materials. Bowtie design #3 eliminates the beam hardening effect in the reconstructed image by adjusting the bowtie filter thickness so that the effective attenuation coefficient for every ray is the same. All three designs are obtained using analytical computational methods and linear attenuation coefficients. Thus, the designs do not take into account the effects of scatter. The authors considered this to be a reasonable approach to the filter design problem since the use of Monte Carlo methods would have been computationally intensive. The filter profiles for a cone-angle of 0° were used for the entire length of each filter because the differences between those profiles and the correct cone-beam profiles for the cone angles in our system are very small, and the constant profiles allowed construction of the filters with the facilities available to us. For evaluation of the filters, we used Monte Carlo simulation techniques and the full cone-beam geometry. Images were generated with and without each bowtie filter to analyze the effect on dose distribution, noise uniformity, and contrast-to-noise ratio (CNR) homogeneity. Line profiles through the reconstructed images generated from the simulated projection images were also used as validation for the filter designs. Results: Examples of the three designs are

  6. 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

  7. 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

  8. 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

  9. Preparing Dedicated Education Unit Staff Nurses for the Role of Clinical Teacher.

    PubMed

    Seibert, Susan A; Bonham, Elizabeth

    2016-01-01

    Dedicated Education Units optimize the expertise of staff nurses to provide clinical instruction to nursing students, thereby creating a need to prepare staff nurses for the teaching role and educate them about clinical teaching strategies. A curriculum to educate Dedicated Education Unit staff nurses in the art of clinical instruction was created to fill this gap in staff development. This article describes the development of an innovative, interactive, evidence-based curriculum to prepare Dedication Education Unit staff nurses and strengthen an academic-practice partnership.

  10. Preparing Dedicated Education Unit Staff Nurses for the Role of Clinical Teacher.

    PubMed

    Seibert, Susan A; Bonham, Elizabeth

    2016-01-01

    Dedicated Education Units optimize the expertise of staff nurses to provide clinical instruction to nursing students, thereby creating a need to prepare staff nurses for the teaching role and educate them about clinical teaching strategies. A curriculum to educate Dedicated Education Unit staff nurses in the art of clinical instruction was created to fill this gap in staff development. This article describes the development of an innovative, interactive, evidence-based curriculum to prepare Dedication Education Unit staff nurses and strengthen an academic-practice partnership. PMID:27434320

  11. Multiscale Informatics for Low-Temperature Propane Oxidation: Further Complexities in Studies of Complex Reactions.

    PubMed

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

    2015-07-16

    The present paper describes further development of the multiscale informatics approach to kinetic model formulation of Burke et al. (Burke, M. P.; Klippenstein, S. J.; Harding, L. B. Proc. Combust. Inst. 2013, 34, 547-555) that directly incorporates elementary kinetic theories as a means to provide reliable, physics-based extrapolation of kinetic models to unexplored conditions. Here, we extend and generalize the multiscale informatics strategy to treat systems of considerable complexity-involving multiwell reactions, potentially missing reactions, nonstatistical product branching ratios, and non-Boltzmann (i.e., nonthermal) reactant distributions. The methodology is demonstrated here for a subsystem of low-temperature propane oxidation, as a representative system for low-temperature fuel oxidation. A multiscale model is assembled and informed by a wide variety of targets that include ab initio calculations of molecular properties, rate constant measurements of isolated reactions, and complex systems measurements. Active model parameters are chosen to accommodate both "parametric" and "structural" uncertainties. Theoretical parameters (e.g., barrier heights) are included as active model parameters to account for parametric uncertainties in the theoretical treatment; experimental parameters (e.g., initial temperatures) are included to account for parametric uncertainties in the physical models of the experiments. RMG software is used to assess potential structural uncertainties due to missing reactions. Additionally, branching ratios among product channels are included as active model parameters to account for structural uncertainties related to difficulties in modeling sequences of multiple chemically activated steps. The approach is demonstrated here for interpreting time-resolved measurements of OH, HO2, n-propyl, i-propyl, propene, oxetane, and methyloxirane from photolysis-initiated low-temperature oxidation of propane at pressures from 4 to 60 Torr and

  12. Effect of ceria on hydrogen production by auto-thermal reforming of propane over supported nickel catalysts.

    PubMed

    Kim, Woo Ri; Ahn, Ho Geun; Shin, Jae Soon; Kim, Young Chul; Moon, Dong Ju; Park, Nam Cook

    2013-01-01

    Autothermal reforming of propane was studied with respect to the addition of ceria to the supported Ni catalysts. Ni/Al2O3 catalysts showed a higher activity than Ni/MgAl catalysts. It was related to the ease of the catalyst reduction. Ni/Ce/MgAl and Ni/Ce/Al2O3 catalysts showed higher propane conversions and higher hydrogen yields. These were related to the particle size and the reducibilities of the catalysts. XRD analysis showed that the added CeO2 decreased the particle sizes of the supported Ni, but increased the amount of NiO on the catalyst surface, thus it improved the resistance to coking. PMID:23646791

  13. 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.

  14. Three cases of sudden death due to butane or propane gas inhalation: analysis of tissues for gas components.

    PubMed

    Sugie, Hideaki; Sasaki, Chizuko; Hashimoto, Chikako; Takeshita, Hiroshi; Nagai, Tomonori; Nakamura, Shigeki; Furukawa, Masataka; Nishikawa, Takashi; Kurihara, Katsuyoshi

    2004-07-16

    We report three cases of sudden death due to inhalation of portable cooking stove fuel (case 1), cigarette lighter fuel (case 2), and liquefied petroleum gas (LPG) (case 3). Specimens of blood, urine, stomach contents, brain, heart, lung, liver, kidney, and fat were collected and analyzed for propylene, propane, isobutane, and n-butane by headspace gas chromatography. n-Butane was the major substance among the volatiles found in the tissues of cases 1 and 2, and propane was the major substance in case 3. A combination of the autopsy findings and the gas analysis results revealed that the cause of death was ventricular fibrillation induced by hard muscle exercise after gas inhalation in cases 1 and 2, and that the cause of death in case 3 might be hypoxia. It is possible that the victim in case 3 was under anesthetic toxicity of accumulated isobutane which is a minor component of liquefied petroleum gas.

  15. 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.

  16. Study of GaN doping with carbon from propane in a wide range of MOVPE conditions

    NASA Astrophysics Data System (ADS)

    Lundin, W. V.; Sakharov, A. V.; Zavarin, E. E.; Kazantsev, D. Yu.; Ber, B. Ya.; Yagovkina, M. A.; Brunkov, P. N.; Tsatsulnikov, A. F.

    2016-09-01

    Complex studies of intentional GaN carbon doping from propane during MOVPE were performed in a wide range of growth conditions. A strong dependence of carbon doping efficiency on growth rate and ammonia flow is revealed, while dependence of carbon doping efficiency on reactor pressure is small. Atomic force microscopy confirms the good quality of the GaN:C layers for doping levels as high as 2*1019 cm-3 grown with growth rate up to 45 μm/h. The dependence of carbon incorporation into GaN is proportional to the propane concentration to the power 3/2 in most growth regimes, but for very high growth rate a linear or sub-linear component of the dependence becomes prominent.

  17. Calculations of NMR properties for sI and sII clathrate hydrates of methane, ethane and propane.

    PubMed

    Siuda, Paweł; Sadlej, Joanna

    2014-12-01

    Calculations of NMR parameters (the absolute shielding constants and the spin-spin coupling constants) for 5(12), 5(12)6(2) and 5(12)6(4) cages enclathrating CH4, C2H6 and C3H8 molecules are presented. The DFT/B3LYP/HuzIII-su3 level of theory was employed. The (13)C shielding constants of guest molecules are close to available experimental data. In two cases (the ethane in 5(12) and the propane in 5(12)6(2) cages) the (13)C shielding constants are reported for the first time. Inversion of the methyl/methylene (13)C and (1)H shielding constants order is found for propane in the 5(12)6(2) cage. Topological criteria are used to interpret the changes of values of NMR parameters of water molecules and they establish a connection between single cages and bulk crystal.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. Anomalous reactivity of supported V2O5 nanoparticles for propane oxidative dehydrogenation: influence of the vanadium oxide precursor.

    PubMed

    Carrero, Carlos A; Keturakis, Christopher J; Orrego, Andres; Schomäcker, Reinhard; Wachs, Israel E

    2013-09-21

    The oxidative dehydrogenation (ODH) of propane to propylene by supported vanadia catalysts has received much attention in recent years, but different reactivity trends have been reported for this catalytic reaction system. In the present investigation, the origin of these differing trends are investigated with synthesis of supported V/SiO2, V/TiO2, and V/Al2O3 catalysts prepared with three different vanadium oxide precursors (2-propanol/vanadyl triisopropoxide [VO(O-Pri)3] (VTI), oxalic acid/ammonium metavanadate [NH4VO3] (AMV), and toluene/vanadyl acetylacetonate [VO(C5H7O2)2] (VAA)) in order to elucidate the influence of the precursor on supported vanadia phase and propane ODH activity. In situ Raman spectroscopy revealed that the choice of vanadium precursor does not affect the dispersion of the supported vanadium oxide phase below 4 V nm(-2) (0.5 monolayer coverage), where only isolated and oligomeric surface VO4 species are present, and only the AMV precursor favors crystalline V2O5 nanoparticle (NP) formation below monolayer coverage (8 V nm(-2)). The propane ODH specific reactivity trend demonstrated that there is no significant difference in TOF for the isolated and oligomeric surface VO4 sites. Surprisingly, V2O5 NPs in the ∼1-2 nm range exhibit anomalously high propane ODH TOF values for the supported vanadia catalysts. This was found for all supported vanadium oxide catalysts examined. This comparative study with different V-precursors and synthesis methods and oxide supports finally resolves the debate in the catalysis literature about the dependence of TOF on the surface vanadium density that is related to the unusually high reactivity of small V2O5 NPs.

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

    PubMed

    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. PMID:25437228

  5. Identification of Novel Methane-, Ethane-, and Propane-Oxidizing Bacteria at Marine Hydrocarbon Seeps by Stable Isotope Probing ▿ †

    PubMed Central

    Redmond, Molly C.; Valentine, David L.; Sessions, Alex L.

    2010-01-01

    Marine hydrocarbon seeps supply oil and gas to microorganisms in sediments and overlying water. We used stable isotope probing (SIP) to identify aerobic bacteria oxidizing gaseous hydrocarbons in surface sediment from the Coal Oil Point seep field located offshore of Santa Barbara, California. After incubating sediment with 13C-labeled methane, ethane, or propane, we confirmed the incorporation of 13C into fatty acids and DNA. Terminal restriction fragment length polymorphism (T-RFLP) analysis and sequencing of the 16S rRNA and particulate methane monooxygenase (pmoA) genes in 13C-DNA revealed groups of microbes not previously thought to contribute to methane, ethane, or propane oxidation. First, 13C methane was primarily assimilated by Gammaproteobacteria species from the family Methylococcaceae, Gammaproteobacteria related to Methylophaga, and Betaproteobacteria from the family Methylophilaceae. Species of the latter two genera have not been previously shown to oxidize methane and may have been cross-feeding on methanol, but species of both genera were heavily labeled after just 3 days. pmoA sequences were affiliated with species of Methylococcaceae, but most were not closely related to cultured methanotrophs. Second, 13C ethane was consumed by members of a novel group of Methylococcaceae. Growth with ethane as the major carbon source has not previously been observed in members of the Methylococcaceae; a highly divergent pmoA-like gene detected in the 13C-labeled DNA may encode an ethane monooxygenase. Third, 13C propane was consumed by members of a group of unclassified Gammaproteobacteria species not previously linked to propane oxidation. This study identifies several bacterial lineages as participants in the oxidation of gaseous hydrocarbons in marine seeps and supports the idea of an alternate function for some pmoA-like genes. PMID:20675448

  6. 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.

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

    PubMed

    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.

  8. Theoretical evidence for inconsistencies in experimental bubble nucleation rates of propane/CO2 and R22/CO2 mixtures

    NASA Astrophysics Data System (ADS)

    Němec, Tomáš

    2015-12-01

    A binary formulation of the classical nucleation theory (CNT) is developed for homogeneous bubble nucleation in systems composed of a liquid solvent and a dissolved gas. The CNT predictions coincide with experimental nucleation data from the literature for diethylether/N2 and isobutane/CO2 mixtures, while several inconsistencies are identified for propane/CO2 and R22/CO2 experimental datasets.

  9. 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...

  10. 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.

  11. 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.

  12. 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.

  13. 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).

  14. Super critical fluid extraction of a crude oil bitumen-derived liquid and bitumen by carbon dioxide and propane

    SciTech Connect

    Deo, M.D.; Hwang, J.; Hanson, F.V.

    1991-12-31

    Supercritical fluid extraction of complex hydrocarbon mixtures is important in separation processes, petroleum upgrading and enhanced oil recovery. In this study, a paraffinic crude oil, a bitumen- derived liquid and bitumen were extracted at several temperatures and pressures with carbon dioxide and propane to assess the effect of the size and type of compounds that makeup the feedstock on the extraction process. It was observed that the pure solvent density at the extraction conditions was not the sole variable governing extraction, and that the proximity of the extraction conditions to the pure solvent critical point affected the extraction yields and the compositions of the extracts. Heavier compounds reported to the extract phase as the extraction time increased at constant temperature and pressure and as the extraction pressure increased at constant temperature and extraction time for both the paraffin crude-propane and the bitumen-propane systems. This preferential extraction was not observed for the bitumen-derived liquid. The non-discriminatory extraction behavior of the bitumen-derived liquid was attributed to its thermal history and to the presence of the olefins and aromatics in the liquid. Phase behavior calculations using the Peng-Robinson equation of state and component lumping procedures provided reasonable agreement between calculated and experimental results for the crude oil and bitumen extractions, but failed in the prediction of the phase compositions for the bitumen-derived liquid extractions.

  15. 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.

  16. 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.

  17. Carbon dynamics on the molybdenum carbide surface during catalytic propane dehydrogenation.

    PubMed

    Frank, Benjamin; Cotter, Thomas P; Schuster, Manfred E; Schlögl, Robert; Trunschke, Annette

    2013-12-01

    The effect of the gas-phase chemical potential on surface chemistry and reactivity of molybdenum carbide has been investigated in catalytic reactions of propane in oxidizing and reducing reactant mixtures by adding H2, O2, H2O, and CO2 to a C3H8/N2 feed. The balance between surface oxidation state, phase stability, carbon deposition, and the complex reaction network involving dehydrogenation reactions, hydrogenolysis, metathesis, water-gas shift reaction, hydrogenation, and steam reforming is discussed. Raman spectroscopy and a surface-sensitive study by means of in situ X-ray photoelectron spectroscopy evidence that the dynamic formation of surface carbon species under a reducing atmosphere strongly shifts the product spectrum to the C3-alkene at the expense of hydrogenolysis products. A similar response of selectivity, which is accompanied by a boost of activity, is observed by tuning the oxidation state of Mo in the presence of mild oxidants, such as H2O and CO2, in the feed as well as by V doping. The results obtained allow us to draw a picture of the active catalyst surface and to propose a structure-activity correlation as a map for catalyst optimization. PMID:24248701

  18. Autothermal reforming of propane over Ni catalysts supported on a variety of perovskites.

    PubMed

    Lim, SeungSoo; Moon, DongJu; Kim, JongHo; Kim, YoungChul; Park, NamCook; Shin, JaeSoon

    2007-11-01

    Autothermal reforming of propane for hydrogen over Ni catalysts supported on a variety of perovskites was performed in an atmospheric flow reactor. Perovskite is known for its higher thermal stability and oxygen storage capacity, but catalytic activity of itself is low. A sites of the ABO3 structured perovskites were occupied by La while B sites by one of Fe, Co, Ni, and Al by citrate method. The composition of the reactant mixture was H2O/C/O2 = 8.96/1.0/1.1. The changes in the states of the catalysts after reaction were analyzed by XRD, TPD, and TGA. Ni/LaAlO3 catalyst maintained the perovskite structure after reaction. It showed higher hydrogen yield and thermal stability compared to those of the catalysts with Fe, Co, or Ni in B sites. Catalysts prepared by deposition-precipitation (DP) method showed higher activity than those prepared by impregnation method, presumably due to the smaller sizes of the NiO crystal particles.

  19. Chromium and ruthenium-doped zinc oxide thin films for propane sensing applications.

    PubMed

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

    2013-03-12

    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.

  20. Subnanometer platinum clusters highly active and selective catalysts for the oxidative dehydrogenation of propane.

    SciTech Connect

    Vajda, S; Pellin, M. J.; Greeley, J. P.; Marshall, C. L.; Curtiss, L. A.; Ballentine, G. A.; Elam, J. W.; Catillon-Mucherie, S.; Redfern, P. C.; Mehmood, F.; Zapol, P.; Yale Univ.

    2009-03-01

    Small clusters are known to possess reactivity not observed in their bulk analogues, which can make them attractive for catalysis. Their distinct catalytic properties are often hypothesized to result from the large fraction of under-coordinated surface atoms. Here, we show that size-preselected Pt{sub 8-10} clusters stabilized on high-surface-area supports are 40-100 times more active for the oxidative dehydrogenation of propane than previously studied platinum and vanadia catalysts, while at the same time maintaining high selectivity towards formation of propylene over by-products. Quantum chemical calculations indicate that under-coordination of the Pt atoms in the clusters is responsible for the surprisingly high reactivity compared with extended surfaces. We anticipate that these results will form the basis for development of a new class of catalysts by providing a route to bond-specific chemistry, ranging from energy-efficient and environmentally friendly synthesis strategies to the replacement of petrochemical feedstocks by abundant small alkanes.

  1. Mechanism of influence water vapor on combustion characteristics of propane-air mixture

    NASA Astrophysics Data System (ADS)

    Larionov, V. M.; Mitrofanov, G. A.; Sachovskii, A. V.; Kozar, N. K.

    2016-01-01

    The article discusses the results of an experimental study of the effect of water vapor at the flame temperature. Propane-butane mixture with air is burning on a modified Bunsen burner. Steam temperature was varied from 180 to 260 degrees. Combustion parameters changed by steam temperature and its proportion in the mixture with the fuel. The fuel-air mixture is burned in the excess air ratio of 0.1. It has been established that the injection of steam changes the characteristics of combustion fuel-air mixture and increase the combustion temperature. The concentration of CO in the combustion products is substantially reduced. Raising the temperature in the combustion zone is associated with increased enthalpy of the fuel by the added steam enthalpy. Reducing the concentration of CO is caused by decrease in the average temperature in the combustion zone by applying steam. Concentration of active hydrogen radicals and oxygen increases in the combustion zone. That has a positive effect on the process of combustion.

  2. 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.

  3. 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.

  4. 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.

  5. Soot formation and temperature field structure in laminar propane-air diffusion flames at elevated pressures

    SciTech Connect

    Bento, Decio S.; Guelder, OEmer L.; Thomson, Kevin A.

    2006-06-15

    The effect of pressure on soot formation and the structure of the temperature field was studied in coflow propane-air laminar diffusion flames over the pressure range of 0.1 to 0.73 MPa in a high-pressure combustion chamber. The fuel flow rate was selected so that the soot was completely oxidized within the visible flame and the flame was stable at all pressures. Spectral soot emission was used to measure radially resolved soot volume fraction and soot temperature as a function of pressure. Additional soot volume fraction measurements were made at selected heights using line-of-sight light attenuation. Soot concentration values from these two techniques agreed to within 30% and both methods exhibited similar trends in the spatial distribution of soot concentration. Maximum line-of-sight soot concentration along the flame centerline scaled with pressure; the pressure exponent was about 1.4 for pressures between 0.2 and 0.73 MPa. Peak carbon conversion to soot, defined as the percentage of fuel carbon content converted to soot, also followed a power-law dependence on pressure, where the pressure exponent was near to unity for pressures between 0.2 and 0.73 MPa. Soot temperature measurements indicated that the overall temperatures decreased with increasing pressure; however, the temperature gradients increased with increasing pressure. (author)

  6. 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.

  7. Structural evolution of an intermetallic Pd-Zn catalyst selective for propane dehydrogenation.

    PubMed

    Gallagher, James R; Childers, David J; Zhao, Haiyan; Winans, Randall E; Meyer, Randall J; Miller, Jeffrey T

    2015-11-14

    We report the structural evolution of Pd-Zn alloys in a 3.6% Pd-12% Zn/Al2O3 catalyst which is selective for propane dehydrogenation. High signal-to-noise, in situ synchrotron X-ray diffraction (XRD) was used quantitatively, in addition to in situ diffuse-reflectance infrared Fourier transform spectroscopy (DRIFTS) and extended X-ray absorption fine structure (EXAFS) to follow the structural changes in the catalyst as a function of reduction temperature. XRD in conjunction with DRIFTS of adsorbed CO indicated that the β1-PdZn intermetallic alloy structure formed at reduction temperatures as low as 230 °C, likely first at the surface, but did not form extensively throughout the bulk until 500 °C which was supported by in situ EXAFS. DRIFTS results suggested there was little change in the surfaces of the nanoparticles above 325 °C. The intermetallic alloy which formed was Pd-rich at all temperatures but became less Pd-rich with increasing reduction temperature as more Zn incorporated into the structure. In addition to the β1-PdZn alloy, a solid solution phase with face-center cubic structure (α-PdZn) was present in the catalyst, also becoming more Zn-rich with increasing reduction temperature.

  8. A rapid compression machine study of the oxidation of propane in the negative temperature coefficient regime

    SciTech Connect

    Gallagher, S.M.; Curran, H.J.; Metcalfe, W.K.; Healy, D.; Simmie, J.M.; Bourque, G.

    2008-04-15

    The oxidation of propane has been studied in the temperature range 680-970 K at compressed gas pressures of 21, 27, and 37 atm and at varying equivalence ratios of 0.5, 1.0, and 2.0. These data are consistent with other experiments presented in the literature for alkane fuels in that, when ignition delay times are plotted as a function of temperature, a characteristic negative coefficient behavior is observed. In addition, these data were simulated using a detailed chemical kinetic model. It was found that qualitatively the model correctly simulated the effect of change in equivalence ratio and pressure, predicting that fuel-rich, high-pressure mixtures ignite fastest, while fuel-lean, low-pressure mixtures ignite slowest. Moreover, reactivity as a function of temperature is well captured, with the model predicting negative temperature coefficient behavior similar to the experiments. Quantitatively the model is faster than experiment for all mixtures at the lowest temperatures (650-750 K) and is also faster than experiment throughout the entire temperature range for fuel-lean mixtures. (author)

  9. Turbulent Burning Velocities of Two-Component Fuel Mixtures of Methane, Propane and Hydrogen

    NASA Astrophysics Data System (ADS)

    Kido, Hiroyuki; Nakahara, Masaya; Hashimoto, Jun; Barat, Dilmurat

    In order to clarify the turbulent burning velocity of multi-component fuel mixtures, both lean and rich two-component fuel mixtures, in which methane, propane and hydrogen were used as fuels, were prepared while maintaining the laminar burning velocity approximately constant. A distinct difference in the measured turbulent burning velocity at the same turbulence intensity is observed for two-component fuel mixtures having different addition rates of fuel, even the laminar burning velocities are approximately the same. The burning velocities of lean mixtures change almost constantly as the rate of addition changes, whereas the burning velocities of the rich mixtures show no such tendency. This trend can be explained qualitatively based on the mean local burning velocity, which is estimated by taking into account the preferential diffusion effect for each fuel component. In addition, a model of turbulent burning velocity proposed for single-component fuel mixtures may be applied to two-component fuel mixtures by considering the estimated mean local burning velocity of each fuel.

  10. 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.

  11. 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.

  12. 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

  13. 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. PMID:25892815

  14. 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. PMID:27282951

  15. 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

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

    DOE PAGESBeta

    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 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

  17. 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...

  18. 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...

  19. 33 CFR 157.10a - Segregated ballast tanks, crude oil washing systems, and dedicated clean ballast tanks for...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... oil washing systems, and dedicated clean ballast tanks for certain new and existing vessels of 40,000... oil washing systems, and dedicated clean ballast tanks for certain new and existing vessels of 40,000... section; or (2) Dedicated clean ballast tanks that have a total capacity to meet the draft and...

  20. 33 CFR 157.10b - Segregated ballast tanks, dedicated clean ballast tanks, and special ballast arrangements for...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., dedicated clean ballast tanks, and special ballast arrangements for tank vessels transporting Outer..., dedicated clean ballast tanks, and special ballast arrangements for tank vessels transporting Outer..., 1980 must, if segregated ballast tanks or dedicated clean ballast tanks are not required under §...

  1. 33 CFR 157.10a - Segregated ballast tanks, crude oil washing systems, and dedicated clean ballast tanks for...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... oil washing systems, and dedicated clean ballast tanks for certain new and existing vessels of 40,000... oil washing systems, and dedicated clean ballast tanks for certain new and existing vessels of 40,000... section; or (2) Dedicated clean ballast tanks that have a total capacity to meet the draft and...

  2. 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...

  3. 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...

  4. 33 CFR 157.10b - Segregated ballast tanks, dedicated clean ballast tanks, and special ballast arrangements for...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., dedicated clean ballast tanks, and special ballast arrangements for tank vessels transporting Outer..., dedicated clean ballast tanks, and special ballast arrangements for tank vessels transporting Outer..., 1980 must, if segregated ballast tanks or dedicated clean ballast tanks are not required under §...

  5. 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...

  6. 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.

  7. Phase diagrams for clathrate hydrates of methane, ethane, and propane from first-principles thermodynamics.

    PubMed

    Cao, Xiaoxiao; Huang, Yingying; Li, Wenbo; Zheng, Zhaoyang; Jiang, Xue; Su, Yan; Zhao, Jijun; Liu, Changling

    2016-01-28

    Natural gas hydrates are inclusion compounds composed of major light hydrocarbon gaseous molecules (CH4, C2H6, and C3H8) and a water clathrate framework. Understanding the phase stability and formation conditions of natural gas hydrates is crucial for their future exploitation and applications and requires an accurate description of intermolecular interactions. Previous ab initio calculations on gas hydrates were mainly limited by the cluster models, whereas the phase diagram and equilibrium conditions of hydrate formation were usually investigated using the thermodynamic models or empirical molecular simulations. For the first time, we construct the chemical potential phase diagrams of type II clathrate hydrates encapsulated with methane/ethane/propane guest molecules using first-principles thermodynamics. We find that the partially occupied structures (136H2O·1CH4, 136H2O·16CH4, 136H2O·20CH4, 136H2O·1C2H6, and 136H2O·1C3H8) and fully occupied structures (136H2O·24CH4, 136H2O·8C2H6, and 136H2O·8C3H8) are thermodynamically favorable under given pressure-temperature (p-T) conditions. The theoretically predicted equilibrium pressures for pure CH4, C2H6 and C3H8 hydrates at the phase transition point are consistent with the experimental data. These results provide valuable guidance for establishing the relationship between the accurate description of intermolecular noncovalent interactions and the p-T equilibrium conditions of clathrate hydrates and other molecular crystals.

  8. 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.

  9. Optical measurements of soot and temperature profiles in premixed propane-oxygen flames

    NASA Technical Reports Server (NTRS)

    Lyons, Valerie J.; Pagni, Patrick J.

    1988-01-01

    Two laser diagnostic techniques were used to measure soot volume fractions, number densities and soot particle radii in premixed propane/oxygen flat flames. The two techniques used were two wavelength extinction, using 514.5 nm to 632.8 nm and 457.9 nm to 632.8 nm wavelength combinations, and extinction/scattering using 514.5 nm light. The flames wre fuel-rich (equivalence ratios from 2.1 to 2.8) and had cold gas velocities varying from 3.4 to 5.5 cm/s. Measurements were made at various heights above the sintered-bronze, water-cooled flat flame burner with the equivalence ratio and cold gas velocity fixed. Also, measurements were made at a fixed height above the burner and fixed cold gas velocity while varying the equivalence ratio. Both laser techniques are based on the same underlying assumptions of particle size distribution and soot optical properties. Full Mie theory was used to determine the extinction coefficients K sub ext, and the scattering efficiencies, Q sub vv. Temperature measurements in the flames were made using infrared radiometry. Good agreement between the two techniques in terms of soot particle radii, number density and volume fraction was found for intensity ratios (I/I sub o) between 0.1 and 0.8. For intensity ratios higher or lower than this range, the differences in extinction coefficients at the wavelengths chosen for the two-wavelength method are too small to give accurate results for comparing particle radii and number densities. However, when comparing only soot volume fractions, the agreement between the two techniques continued to be good for intensity ratios up to 0.95.

  10. Optical measurements of soot and temperature profiles in premixed propane-oxygen flames

    NASA Technical Reports Server (NTRS)

    Lyons, V. J.; Pagni, P. J.

    1988-01-01

    Two laser diagnostic techniques were used to measure soot volume fractions, number densities and soot particle radii in premixed propane/oxygen flat flames. The two techniques used were two wavelength extinction, using 514.5 nm to 632.8 nm and 457.9 nm to 632.8 nm wavelength combinations, and extinction/scattering using 514.5 nm light. The flames were fuel-rich (equivalence ratios from 2.1 to 2.8) and had cold gas velocities varying from 3.4 to 5.5 cm/s. Measurements were made at various heights above the sintered-bronze, water-cooled flat flame burner with the equivalence ratio and cold gas velocity fixed. Also, measurements were made at a fixed height above the burner and fixed cold gas velocity while varying the equivalence ratio. Both laser techniques are based on the same underlying assumptions of particle size distribution and soot optical properties. Full Mie theory was used to determine the extinction coefficients K sub ext, and the scattering efficiencies, Q sub vv. Temperature measurements in the flames were made using infrared radiometry. Good agreement between the two techniques in terms of soot particle radii, number density and volume fraction was found for intensity ratios (I/I sub o) between 0.1 and 0.8. For intensity ratios higher or lower than this range, the differences in extinction coefficients at the wavelengths chosen for the two-wavelength method are too small to give accurate results for comparing particle radii and number densities. However, when comparing only soot volume fractions, the agreement between the two techniques continued to be good for intensity ratios up to 0.95.

  11. Phase diagrams for clathrate hydrates of methane, ethane, and propane from first-principles thermodynamics.

    PubMed

    Cao, Xiaoxiao; Huang, Yingying; Li, Wenbo; Zheng, Zhaoyang; Jiang, Xue; Su, Yan; Zhao, Jijun; Liu, Changling

    2016-01-28

    Natural gas hydrates are inclusion compounds composed of major light hydrocarbon gaseous molecules (CH4, C2H6, and C3H8) and a water clathrate framework. Understanding the phase stability and formation conditions of natural gas hydrates is crucial for their future exploitation and applications and requires an accurate description of intermolecular interactions. Previous ab initio calculations on gas hydrates were mainly limited by the cluster models, whereas the phase diagram and equilibrium conditions of hydrate formation were usually investigated using the thermodynamic models or empirical molecular simulations. For the first time, we construct the chemical potential phase diagrams of type II clathrate hydrates encapsulated with methane/ethane/propane guest molecules using first-principles thermodynamics. We find that the partially occupied structures (136H2O·1CH4, 136H2O·16CH4, 136H2O·20CH4, 136H2O·1C2H6, and 136H2O·1C3H8) and fully occupied structures (136H2O·24CH4, 136H2O·8C2H6, and 136H2O·8C3H8) are thermodynamically favorable under given pressure-temperature (p-T) conditions. The theoretically predicted equilibrium pressures for pure CH4, C2H6 and C3H8 hydrates at the phase transition point are consistent with the experimental data. These results provide valuable guidance for establishing the relationship between the accurate description of intermolecular noncovalent interactions and the p-T equilibrium conditions of clathrate hydrates and other molecular crystals. PMID:26745181

  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. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. High-temperature catalytic oxidative conversion of propane to propylene and ethylene involving coupling of exothermic and endothermic reactions

    SciTech Connect

    Choudhary, V.R.; Rane, V.H.; Rajput, A.M.

    2000-04-01

    Coupling of the exothermic catalytic oxidative conversion and endothermic thermal cracking (noncatalytic) reactions of propane to propylene and ethylene over the SrO/La{sub 2}O{sub 3}/SA5205 catalyst in the presence of steam and limited oxygen was investigated at different process conditions (temperature, 700--850 C; C{sub 3}H{sub 8}/O{sub 2} ratio in feed, 2.0--8.0; H{sub 2}O/C{sub 3}H{sub 8} ratio, 0.5--2.5; space velocity, 2,000--15,000 cm{sup 3}/g h). In the presence of steam and limited O{sub 2}, the endothermic thermal cracking and exothermic oxidative conversion reactions occur simultaneously and there is no coke formation on the catalyst. Because of the direct coupling of exothermic and endothermic reactions, this process occurs in a most energy efficient and safe manner. The propane conversion, selectivity for propylene, and net heat of reaction ({Delta}H{sub r}) in the process are strongly influenced by the temperature and concentration of O{sub 2} relative to the propane in the feed. The C{sub 3}H{sub 6}/C{sub 2}H{sub 4} product ratio is also strongly influenced by the temperature, C{sub 3}H{sub 8}/O{sub 2} feed ratio, and space velocity. The net heat of reaction can be controlled by manipulating the reaction temperature and C{sub 3}H{sub 8}/O{sub 2} ratio in the feed; the process exothermicity is reduced drastically with increasing the temperature and/or C{sub 3}H{sub 8}/O{sub 2} feed ratio.

  19. 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.

  20. Synthesis and spectral characterization of bis(4-amino-5-mercapto-1,2,4-triazol-3-yl)propane

    NASA Astrophysics Data System (ADS)

    Subashchandrabose, S.; Thanikachalam, V.; Manikandan, G.; Saleem, H.; Erdogdu, Y.

    2016-03-01

    Bis(4-amino-5-mercapto-1,2,4-triazol-3-yl)propane (BAMTP) was synthesized and characterized by FT-IR and FT-Raman spectra. Gas phase structure of BAMTP was examined under density functional theory B3LYP/6-311 ++G(d, p) level of basis set, wherein the molecule was subjected to conformational analysis. Thus the identified stable structure utilized for the calculations such as geometry optimization, vibrational behavior, hyperpolarizability analysis, natural bond orbital analysis, band gap, chemical hard/softness and stability. Geometry of BAMTP has been discussed elaborately with related crystal data. The results found from experimental and theoretical methods were reported herewith.

  1. 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.

  2. Crystal structure of di­bromido­tetra­kis(propan-2-ol-κO)nickel(II)

    PubMed Central

    Lv, Yaokang; Liu, Mingxian; Ji, Lvlv; Zhang, Cheng; Ouyang, Mi

    2015-01-01

    The asymmetric unit of the mononuclear title complex, [NiBr2(C3H8O)4], comprises a NiII cation located on a centre of inversion, one Br− anion and two propan-2-ol ligands. The NiII cation exhibits a distorted trans-Br2O4 environment. There are O—H⋯Br hydrogen bonds connecting neighbouring mol­ecules into rows along [100]. These rows are arranged in a distorted hexa­gonal packing and are held together by van der Waals forces only. PMID:26870456

  3. Theoretical study of interactions between 2,2-Bis (ethylferrocenyl) propane and ammonium perchlorate at low temperature

    NASA Astrophysics Data System (ADS)

    Zhou, Junhong; Zhang, Wei; Yang, Jun; Jiang, Benzheng; Chen, Weiming

    2016-05-01

    In order to explore the interaction mechanism between 2,2-Bis (ethylferrocenyl) propane (GFP) and ammonium perchlorate (AP) at low temperature (below 250 °C), all the possible intermolecular interactions between GFP and AP were calculated. The calculations were performed in single molecule, cluster and slab models. The calculation results show that the interactions between GFP and AP at low temperature mainly come from GFP-H+ and GFP-NH4+ pair interactions. We speculate that the interaction mechanism between GFP and AP at low temperature is that GFP/H+ or GFP/NH4+ interactions cause GFP to be protonated, and then protonated GFP is to further oxidized.

  4. Microbial oxidation of methane, ethane, propane, and butane in marine gas seeps

    NASA Astrophysics Data System (ADS)

    Kinnaman, F. S.; Valentine, D. L.; Tyler, S.

    2005-12-01

    The microbial consumption of methane (C1), ethane (C2), propane (C3) and n-butane (nC4) in marine gas seeps was investigated using a stable isotope approach. Sediment samples were collected from the shallow hydrocarbon seeps at Coal Oil Point, Santa Barbara, CA and were used to quantify the natural distributions of C1-C4 hydrocarbons (concentrations and 13C) and as inoculum for laboratory experiments designed to quantify stable isotope fractionation associated with microbial C1-C4 consumption. Stable carbon isotope analyses of C1-C4 dissolved in pore fluids display significant enrichments in the 13C content of C1-C4 compared to the seep gas, and are interpreted as an indication of microbial oxidation. Distributions of sulfate in the sediment pore fluids indicate significant advection of pore fluids into the sediments likely driven by bubble flux. The advective flux of seawater into the sediments presumably expands the oxic zone and creates a habitat suitable for the aerobic oxidation of C1-C4. The maximum extent of oxidation was observed at a distance of 4-8 cm from individual gas vents, and at a depth of 6-10cm. Laboratory incubations of seep sediment demonstrate microbial consumption of C1-C4 hydrocarbons. Carbon and hydrogen isotope fractionation factors (ɛc and ɛh) for the aerobic oxidation of C1-C4 were determined as follows: ɛc was -31.4‰ ±1.6 for C1, -8.8‰ ±1.8 for C2, -5.4‰ ±0.7 for C3, and -3.1‰ ±0.7 for nC4; ɛh was -201.9‰ ±33.7, -62.7‰ ±7.4 for C2, and -16.3‰ ±2.0 for C3. Preferential oxidation of higher molecular weight hydrocarbons was noted in mixed gas incubations, along with possible inhibition of methane oxidation by the presence of C2-C4 gases. Application of the isotopic enrichment factors to observed pore water values indicates that as much as 75% of the dissolved hydrocarbons are consumed in the sediment.

  5. 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

  6. Accurate values of some thermodynamic properties for carbon dioxide, ethane, propane, and some binary mixtures.

    PubMed

    Velasco, Inmaculada; Rivas, Clara; Martínez-López, José F; Blanco, Sofía T; Otín, Santos; Artal, Manuela

    2011-06-30

    Quasicontinuous PρT data of CO(2), ethane, propane, and the [CO(2) + ethane] mixture have been determined along subcritical, critical, and supercritical regions. These data have been used to develop the optimal experimental method and to determine the precision of the results obtained when using an Anton Paar DMA HPM vibrating-tube densimeter. A comparison with data from reference EoS and other authors confirm the quality of our experimental setup, its calibration, and testing. For pure compounds, the value of the mean relative deviation is MRD(ρ) = 0.05% for the liquid phase and for the extended critical and supercritical region. For binary mixtures the mean relative deviation is MRD(ρ) = 0.70% in the range up to 20 MPa and MRD(ρ) = 0.20% in the range up to 70 MPa. The number of experimental points measured and their just quality have enable us to determine some derivated properties with satisfactory precision; isothermal compressibilities, κ(T), have been calculated for CO(2) and ethane (MRD(κ(T)) = 1.5%), isobaric expasion coefficients, α(P), and internal pressures, π(i), for CO(2) (MRD(α(P)) = 5% and MRD(π(i)) = 7%) and ethane (MRD(α(P)) = 7.5% and MRD(π(i)) = 8%). An in-depth discussion is presented on the behavior of the properties obtained along subcritical, critical, and supercritical regions. In addition, PuT values have been determined for water and compressed ethane from 273.19 to 463.26 K up to pressures of 190.0 MPa, using a device based on a 5 MHz pulsed ultrasonic system (MRD(u) = 0.1%). With these data we have calibrated the apparatus and have verified the adequacy of the operation with normal liquids as well as with some compressed gases. From density and speed of sound data of ethane, isentropic compressibilities, κ(s), have been obtained, and from these and our values for κ(T) and α(P), isobaric heat capacities, C(p), have been calculated with MRD(C(p)) = 3%, wich is within that of the EoS. PMID:21639086

  7. High-Pressure Micellar Solutions of Polystyrene-block-Polybutadiene and Polystyrene-block-Polyisoprene Solutions in Propane Exhibit Cloud-Pressure Reduction and Distinct Micellization End Points

    SciTech Connect

    Winoto, Winoto; Radosz, Maciej; Tan, Sugata; Hong, Kunlun; Mays, Jimmy

    2009-01-01

    Micellar solutions of polystyrene-block-polybutadiene and polystyrene-block-polyisoprene in propane are found to exhibit significantly lower cloud pressures than the corresponding hypothetical non-micellar solutions. Such a cloud-pressure reduction indicates the extent to which micelle formation enhances the apparent diblock solubility in near-critical and hence compressible propane. Pressure-temperature points beyond which no micelles can be formed, referred to as the micellization end points, are found to depend on the block type, size and ratio, and on the polymer concentration. For a given pressure, the micellization end-point temperature corresponds to the "critical micelle temperature." The cloud-pressure reduction and the micellization end point measured for styrene-diene diblocks in propane should be characteristic of all amphiphilic diblock copolymer solutions that form micelles in compressible solvents.

  8. 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.

  9. Commercial grade item (CGI) dedication of MDR relays for nuclear safety related applications

    NASA Astrophysics Data System (ADS)

    Das, Ranjit K.; Julka, Anil; Modi, Govind

    1994-08-01

    MDR relays manufactured by Potter & Brumfield (P&B) have been used in various safety related applications in commercial nuclear power plants. These include emergency safety features (ESF) actuation systems, emergency core cooling systems (ECCS) actuation, and reactor protection systems. The MDR relays manufactured prior to May 1990 showed signs of generic failure due to corrosion and outgassing of coil varnish. P&B has made design changes to correct these problems in relays manufactured after May 1990. However, P&B does not manufacture the relays under any 10CFR50 Appendix B quality assurance (QA) program. They manufacture the relays under their commercial QA program and supply these as commercial grade items. This necessitates CGI Dedication of these relays for use in nuclear-safety-related applications. This paper presents a CGI dedication program that has been used to dedicate the MDR relays manufactured after been used to dedicate the MDR relays manufactured after May 1990. The program is in compliance with current Nuclear Regulatory Commission (NRC) and Electric Power Research Institute (EPRI) guidelines and applicable industry standards; it specifies the critical characteristics of the relays, provides the tests and analysis required to verify the critical characteristics, the acceptance criteria for the test results, performs source verification to quality P&B for its control of the critical characteristics, and provides documentation. The program provides reasonable assurance that the new MDR relays will perform their intended safety functions.

  10. Utilization of a New Declaratory Judgment Procedure by Organizations Dedicated to Advancement of the Arts.

    ERIC Educational Resources Information Center

    Weithorn, Stanley S.

    1978-01-01

    As a part of the Tax Reform Act of 1976, Congress authorized certain nonprofit organizations, including those dedicated to the advancement of the arts, to seek judicial determinations as to their tax status as organizations classified in the Internal Revenue Code. Two Internal Revenue Service form letters are appended. (JMD)

  11. 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,…

  12. The effect of a dedicated Ponseti service on the outcome of idiopathic clubfoot treatment.

    PubMed

    Mayne, A I W; Bidwai, A S; Beirne, P; Garg, N K; Bruce, C E

    2014-10-01

    We report the effect of introducing a dedicated Ponseti service on the five-year treatment outcomes of children with idiopathic clubfoot. Between 2002 and 2004, 100 feet (66 children; 50 boys and 16 girls) were treated in a general paediatric orthopaedic clinic. Of these, 96 feet (96%) responded to initial casting, 85 requiring a tenotomy of the tendo-Achillis. Recurrent deformity occurred in 38 feet and was successfully treated in 22 by repeat casting and/or tenotomy and/or transfer of the tendon of tibialis anterior, The remaining 16 required an extensive surgical release. Between 2005 and 2006, 72 feet (53 children; 33 boys and 20 girls) were treated in a dedicated multidisciplinary Ponseti clinic. All responded to initial casting: 60 feet (83.3%) required a tenotomy of the tendo-Achillis. Recurrent deformity developed in 14, 11 of which were successfully treated by repeat casting and/or tenotomy and/or transfer of the tendon of tibialis anterior. The other three required an extensive surgical release. Statistical analysis showed that children treated in the dedicated Ponseti clinic had a lower rate of recurrence (p = 0.068) and a lower rate of surgical release (p = 0.01) than those treated in the general clinic. This study shows that a dedicated Ponseti clinic, run by a well-trained multidisciplinary team, can improve the outcome of idiopathic clubfoot deformity. PMID:25274932

  13. 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…

  14. Papers Delivered at the Indiana University Library Dedication, Bloomington Campus, October 9-10, 1970.

    ERIC Educational Resources Information Center

    Indiana Univ., Bloomington.

    The Dedication Address was given by Gordon N. Ray. Alan R. Taylor presented "A Model of Academic Library Service," which was followed by "Views and Reviews," given by Edwin H. Cady; "Comments on 'A Model of Academic Library Service'," by Stephen A. McCarthy and "Critique of Taylor Paper," by Marvin E. Olsen. The other speeches given at this…

  15. 46 CFR 153.491 - Waiver of certain equipment for dedicated cargo tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Waiver of certain equipment for dedicated cargo tanks... DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Design and Equipment for Pollution Control § 153.491 Waiver of certain equipment...

  16. Kinematic and Dynamic Analysis of New Polar Positioning System Dedicated to Mechatronic Laser Glass Engraving System

    NASA Astrophysics Data System (ADS)

    Trochimczuk, R.

    2014-11-01

    Analytical formulas describing the kinematics and dynamics of a multibody system of a new polar positioning system dedicated to mechatronic laser glass or other transparent dielectrics engraving system will be presented in this work. The analytical results will become in the later stages of the research the basis of numerical simulations. They will optimize the proposed solution of the positioning system.

  17. 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

  18. 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)

  19. 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.

  20. A Framework to Assess Regional Environmental Impacts of Dedicated Energy Crop Production

    PubMed

    Graham; Downing; Walsh

    1996-07-01

    Numerous studies have evaluated air quality and greenhouse gas mitigation benefits of biomass energy systems, but the potential environmental impacts associated with large-scale changes in land-use patterns needed to produce energy crops have not been quantified. This paper presents a framework to assess the potential soil, water, and biodiversity impacts that may result from the large-scale production of dedicated energy crops. The framework incorporates producer economic decision models with environmental models to assess changes in land use patterns and to quantify the consequent environmental impacts. Economic and policy issues that will affect decisions to produce energy crops are discussed. The framework is used to evaluate erosion and chemical runoff in two Tennessee regions. The analysis shows that production of dedicated energy crops in place of conventional crops will significantly reduce erosion and chemical runoff.

  1. 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.

  2. Systematic and deliberate orientation and instruction for dedicated education unit staff.

    PubMed

    Smyer, Tish; Tejada, Marianne Bundalian; Tan, Rhigel Alforque

    2015-03-01

    On the basis of increasing complexity of the health care environment and recommended changes in how nurses are educated to meet these challenges, the University of Nevada Las Vegas, School of Nursing established an academic-practice partnership with Summerlin Hospital Medical Center to develop a dedicated education unit (DEU). When the DEU model was implemented, variables that were not discussed in the literature needed to be addressed. One such challenge was how to impart pedagogy related to clinical teaching to the DEU nursing staff who would be acting as clinical dedicated unit instructors (CDIs). Of chief concern was the evaluation and monitoring of the quality of CDI-student interactions to ensure optimal student learning outcomes. This article addresses the development of a deliberate, systematic approach to the orientation and continued education of CDIs in the DEU. This information will assist other nursing programs as they begin to implement DEUs.

  3. 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.

  4. 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.

  5. 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.

  6. Simulation of the Dynamic Behavior of Electric Power Steering Systems Using Dedicated Finite Elements

    NASA Astrophysics Data System (ADS)

    Besson, François; Ferraris, Guy; Guingand, Michèle; Vaujany, Jean-Pierre De

    During the last decade, many new technical solutions dedicated to the comfort of automotive vehicle's drivers have raised, like Electrical Power Steering (EPS). To fulfill the more and more demanding requirements in terms of vibration and acoustics, the dynamic behavior of the whole steering is studied. The system is divided into dedicated finite elements (FE) describing the whole steering. The stress was first put on the gears models (worm gear and rack-and-pinion) and their anti-backlash systems as they have been identified as potential vibration sources. Mechanical non-linearities (clearances, non-linear stiffness) of the mechanical system are taken into account in these models. Then, this model allows simulating the transient response of the system to an input excitation. Each developed element is validated using a fitted experimental test bench. Then, the general model is correlated the same way. Hence models can be used to study the dynamic behavior of EPS systems or sub-systems.

  7. 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

  8. Special Issue dedicated to Sir Alistair G.J. MacFarlane

    NASA Astrophysics Data System (ADS)

    Karcanias, Nicos; Limebeeer, David J. N.

    2013-11-01

    This special issue of the International Journal of Control is dedicated to Sir Alistair MacFarlane. It contains a collection of papers on systems and multivariable control contributed by a number of people, including ex-students and collaborators of Alistair, or those who know Alistair's work, reflecting his diverse interests. During his time in Cambridge, Alistair was Editor of the International Journal of Control.

  9. 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.

  10. 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.

  11. Academic Outcome Measures of a Dedicated Education Unit Over Time: Help or Hinder?

    PubMed

    Smyer, Tish; Gatlin, Tricia; Tan, Rhigel; Tejada, Marianne; Feng, Du

    2015-01-01

    Critical thinking, nursing process, quality and safety measures, and standardized RN exit examination scores were compared between students (n = 144) placed in a dedicated education unit (DEU) and those in a traditional clinical model. Standardized test scores showed that differences between the clinical groups were not statistically significant. This study shows that the DEU model is 1 approach to clinical education that can enhance students' academic outcomes.

  12. [Functionality determinants of the integrated systems dedicated to health care institutions].

    PubMed

    Sokołowski, Adam; Sroka, Mariusz

    2013-01-01

    The Authors of the hereby dissertation aimed at presenting the functionality concept of the integrated e-service platform dedicated to health care institutions. In the form of a problem repository the research results allowing the identification of the functionality determinants were presented. Finally, the study presents the system's structure as well as analyzing the needs for e-services in terms of society and their usefulness evaluated by branch experts. PMID:23905430

  13. 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.

  14. A new fission chamber dedicated to Prompt Fission Neutron Spectra measurements

    NASA Astrophysics Data System (ADS)

    Taieb, J.; Laurent, B.; Bélier, G.; Sardet, A.; Varignon, C.

    2016-10-01

    New fission chambers dedicated to Prompt Fission Neutron Spectra measurements with the time-of-flight technique have been developed. The actinide mass embedded in the chamber was maximized, while the alpha-fission discrimination and the time resolution were optimized. Moreover, to reduce the neutron background and spectra distortions, neutron scattering with the materials were minimized by the choice of material and structure. These chambers were then tested and validated during tests and in-beam experiments.

  15. Benefits of a Dedicated Breastfeeding Facility and Support Program for Exclusive Breastfeeding among Workers in Indonesia

    PubMed Central

    Basrowi, Ray W; Sulistomo, Astrid B; Adi, Nuri Purwito

    2015-01-01

    Purpose A mother's working environment is believed to be a major determinant of exclusive breastfeeding (EBF) practice. We aimed to define the influence of a facility dedicated to breastfeeding and a breastfeeding support program at the workplace on breastfeeding practice. Methods A cross-sectional study was performed in five workplaces. The inclusion criteria were female workers whose last child was between 6 and 36 months old. Observational data were obtained and a questionnaire was filled out. The World Health Organization definition for EBF was used. Results Data from 186 subjects (74 office workers and 112 factory workers) were collected. Just over half (52%) of the mothers were between 20 and 46 years old, 75.3% had graduated from high school and university, 12.9% had more than two children and 36.0% owned a house. The prevalence of EBF during the last 6 months was 32.3%. A proper dedicated breastfeeding facility was available for 21.5% of the mothers, but only 7.5% had been in contact with a breastfeeding support program. The presence of a dedicated breastfeeding facility increased EBF practice almost threefold, by an odds ratio (OR) of 2.74 and a 95% confidence interval (CI) of 1.34-5.64 (p<0.05). Knowledge of the breastfeeding support program increased EBF practice by almost six times (OR, 5.93; 95% CI, 1.78-19.79) (p<0.05). Conclusion Our findings suggest that Governments should make it obligatory for employers to offer a breastfeeding support program and a dedicated breastfeeding facility at the workplace as these simple measures significantly increase EBF. PMID:26157694

  16. A dedicated 26-m SETI sky survey instrument facility: A feasibility study

    NASA Technical Reports Server (NTRS)

    Berman, A. L.; Shaffer, R. D.

    1981-01-01

    The feasibility of converting a deactivated GSTDN 26 m facility into a dedicated SETI Instrument Facility is examined. Additional benefits that would accrue from the proposed utilization of these facilities are the capability for remote and control the Deep Space Communications Complex (DSCC) Signal Processing Center, combined with a reduction in ground-induced radio frequency interference due to the physical distance to the other DSCC front end areas and the Signal Processing Center.

  17. [Functionality determinants of the integrated systems dedicated to health care institutions].

    PubMed

    Sokołowski, Adam; Sroka, Mariusz

    2013-01-01

    The Authors of the hereby dissertation aimed at presenting the functionality concept of the integrated e-service platform dedicated to health care institutions. In the form of a problem repository the research results allowing the identification of the functionality determinants were presented. Finally, the study presents the system's structure as well as analyzing the needs for e-services in terms of society and their usefulness evaluated by branch experts.

  18. 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.

  19. Conformational Selection Underlies Recognition of a Molybdoenzyme by Its Dedicated Chaperone

    PubMed Central

    Lorenzi, Magali; Sylvi, Léa; Gerbaud, Guillaume; Mileo, Elisabetta; Halgand, Frédéric; Walburger, Anne; Vezin, Hervé; Belle, Valérie; Guigliarelli, Bruno; Magalon, Axel

    2012-01-01

    Molecular recognition is central to all biological processes. Understanding the key role played by dedicated chaperones in metalloprotein folding and assembly requires the knowledge of their conformational ensembles. In this study, the NarJ chaperone dedicated to the assembly of the membrane-bound respiratory nitrate reductase complex NarGHI, a molybdenum-iron containing metalloprotein, was taken as a model of dedicated chaperone. The combination of two techniques ie site-directed spin labeling followed by EPR spectroscopy and ion mobility mass spectrometry, was used to get information about the structure and conformational dynamics of the NarJ chaperone upon binding the N-terminus of the NarG metalloprotein partner. By the study of singly spin-labeled proteins, the E119 residue present in a conserved elongated hydrophobic groove of NarJ was shown to be part of the interaction site. Moreover, doubly spin-labeled proteins studied by pulsed double electron-electron resonance (DEER) spectroscopy revealed a large and composite distribution of inter-label distances that evolves into a single preexisting one upon complex formation. Additionally, ion mobility mass spectrometry experiments fully support these findings by revealing the existence of several conformers in equilibrium through the distinction of different drift time curves and the selection of one of them upon complex formation. Taken together our work provides a detailed view of the structural flexibility of a dedicated chaperone and suggests that the exquisite recognition and binding of the N-terminus of the metalloprotein is governed by a conformational selection mechanism. PMID:23185350

  20. Fully Differential Monte-Carlo Generator Dedicated to TMDs and Bessel-Weighted Asymmetries

    SciTech Connect

    Aghasyan, Mher M.; Avakian, Harut A.

    2013-10-01

    We present studies of double longitudinal spin asymmetries in semi-inclusive deep inelastic scattering using a new dedicated Monte Carlo generator, which includes quark intrinsic transverse momentum within the generalized parton model based on the fully differential cross section for the process. Additionally, we apply Bessel-weighting to the simulated events to extract transverse momentum dependent parton distribution functions and also discuss possible uncertainties due to kinematic correlation effects.

  1. 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…

  2. 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.

  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. PMID:26777871

  4. Characterization of scatter magnitude and distribution in dedicated breast computed tomography with bowtie filters

    PubMed Central

    Kontson, Kimberly; Jennings, Robert J.

    2014-01-01

    Abstract. Scatter contamination of projection images in cone-beam computed tomography (CT) degrades the image quality. The use of bowtie filters in dedicated breast CT can decrease this scatter contribution. Three bowtie filter designs that compensate for one or more aspects of the beam-modifying effects due to differences in path length in a projection were studied. These designs have been investigated in terms of their ability to reduce the scatter contamination in projection images acquired in a dedicated breast CT geometry. The scatter magnitude was measured as the scatter-to-primary ratio (SPR) using experimental and Monte Carlo techniques for various breast phantom diameters and tube voltages. The results show that a 55% reduction in the center SPR value could be obtained with the bowtie filter designs. On average, the bowtie filters reduced the center SPR by approximately 18% over all breast diameters. The distribution of the scatter was calculated at a range of different locations to produce scatter distribution maps for all three bowtie filter designs. With the inclusion of the bowtie filters, the scatter distribution was more uniform for all breast diameters. The results of this study will be useful in designing scatter correction methods and understanding the benefits of bowtie filters in dedicated breast CT. PMID:26158057

  5. 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.

  6. Co-translational capturing of nascent ribosomal proteins by their dedicated chaperones

    NASA Astrophysics Data System (ADS)

    Pausch, Patrick; Singh, Ujjwala; Ahmed, Yasar Luqman; Pillet, Benjamin; Murat, Guillaume; Altegoer, Florian; Stier, Gunter; Thoms, Matthias; Hurt, Ed; Sinning, Irmgard; Bange, Gert; Kressler, Dieter

    2015-06-01

    Exponentially growing yeast cells produce every minute >160,000 ribosomal proteins. Owing to their difficult physicochemical properties, the synthesis of assembly-competent ribosomal proteins represents a major challenge. Recent evidence highlights that dedicated chaperone proteins recognize the N-terminal regions of ribosomal proteins and promote their soluble expression and delivery to the assembly site. Here we explore the intuitive possibility that ribosomal proteins are captured by dedicated chaperones in a co-translational manner. Affinity purification of four chaperones (Rrb1, Syo1, Sqt1 and Yar1) selectively enriched the mRNAs encoding their specific ribosomal protein clients (Rpl3, Rpl5, Rpl10 and Rps3). X-ray crystallography reveals how the N-terminal, rRNA-binding residues of Rpl10 are shielded by Sqt1's WD-repeat β-propeller, providing mechanistic insight into the incorporation of Rpl10 into pre-60S subunits. Co-translational capturing of nascent ribosomal proteins by dedicated chaperones constitutes an elegant mechanism to prevent unspecific interactions and aggregation of ribosomal proteins on their road to incorporation.

  7. 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.

  8. Co-translational capturing of nascent ribosomal proteins by their dedicated chaperones

    PubMed Central

    Pausch, Patrick; Singh, Ujjwala; Ahmed, Yasar Luqman; Pillet, Benjamin; Murat, Guillaume; Altegoer, Florian; Stier, Gunter; Thoms, Matthias; Hurt, Ed; Sinning, Irmgard; Bange, Gert; Kressler, Dieter

    2015-01-01

    Exponentially growing yeast cells produce every minute >160,000 ribosomal proteins. Owing to their difficult physicochemical properties, the synthesis of assembly-competent ribosomal proteins represents a major challenge. Recent evidence highlights that dedicated chaperone proteins recognize the N-terminal regions of ribosomal proteins and promote their soluble expression and delivery to the assembly site. Here we explore the intuitive possibility that ribosomal proteins are captured by dedicated chaperones in a co-translational manner. Affinity purification of four chaperones (Rrb1, Syo1, Sqt1 and Yar1) selectively enriched the mRNAs encoding their specific ribosomal protein clients (Rpl3, Rpl5, Rpl10 and Rps3). X-ray crystallography reveals how the N-terminal, rRNA-binding residues of Rpl10 are shielded by Sqt1's WD-repeat β-propeller, providing mechanistic insight into the incorporation of Rpl10 into pre-60S subunits. Co-translational capturing of nascent ribosomal proteins by dedicated chaperones constitutes an elegant mechanism to prevent unspecific interactions and aggregation of ribosomal proteins on their road to incorporation. PMID:26112308

  9. Propane σ-Complexes on PdO(101): Spectroscopic Evidence of the Selective Coordination and Activation of Primary C-H Bonds.

    PubMed

    Zhang, Feng; Pan, Li; Choi, Juhee; Mehar, Vikram; Diulus, John T; Asthagiri, Aravind; Weaver, Jason F

    2015-11-16

    Achieving selective C-H bond cleavage is critical for developing catalytic processes that transform small alkanes to value-added products. The present study clarifies the molecular-level origin for an exceptionally strong preference for propane to dissociate on the crystalline PdO(101) surface via primary C-H bond cleavage. Using reflection absorption infrared spectroscopy (RAIRS) and density functional theory (DFT) calculations, we show that adsorbed propane σ-complexes preferentially adopt geometries on PdO(101) in which only primary C-H bonds datively interact with the surface Pd atoms at low propane coverages and are thus activated under typical catalytic reaction conditions. We show that a propane molecule achieves maximum stability on PdO(101) by adopting a bidentate geometry in which a H-Pd dative bond forms at each CH3 group. These results demonstrate that structural registry between the molecule and surface can strongly influence the selectivity of a metal oxide surface in activating alkane C-H bonds. PMID:26420576

  10. 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

  11. Pd-Ag Membrane Coupled to a Two-Zone Fluidized Bed Reactor (TZFBR) for Propane Dehydrogenation on a Pt-Sn/MgAl2O4 Catalyst.

    PubMed

    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

  12. Structure of the two-subsite beta-D-xylosidase from Selenomonas ruminantium in complex with 1,3-bis[tris(hydroxymethyl)methylamino]propane

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The three-dimensional structure of the catalytically-efficient beta-xylosidase from Selenomonas ruminantium in complex with competitive inhibitor 1,3 bis[tris(hydroxymethyl)methylamino]propane (BTP) was determined by using X-ray crystallography (1.3 Å resolution). Most H bonds between inhibitor and...

  13. Base or nucleophile? DFT finally elucidates the origin of the selectivity between the competitive reactions triggered by MeLi or LDA on propanal.

    PubMed

    Marchois, J; Fressigné, C; Lecachey, B; Maddaluno, J

    2015-06-18

    The competition between basicity and nucleophilicity of two standard organolithium reagents was studied using DFT. Comparing the reactivity of solvated (MeLi)2 and (LDA)2 toward propanal finally explains why methyllithium adds onto the carbonyl while LDA deprotonates the α-position, in accord with experiment and Ireland's deprotonation TS.

  14. Carbon and hydrogen stable isotope fractionation associated with the anaerobic degradation of propane and butane by marine sulfate-reducing bacteria.

    PubMed

    Jaekel, Ulrike; Vogt, Carsten; Fischer, Anko; Richnow, Hans-Hermann; Musat, Florin

    2014-01-01

    The anaerobic degradation of propane and butane is typically initiated by activation via addition to fumarate. Here we investigated the mechanism of activation under sulfate-reducing conditions by one pure culture (strain BuS5) and three enrichment cultures employing stable isotope analysis. Stable isotope fractionation was compared for cultures incubated with or without substrate diffusion limitation. Bulk enrichment factors were significantly higher in mixed vs. static incubations. Two dimensional factors, given by the correlation of stable isotope fractionation of both carbon and hydrogen at their reactive positions (Lambda reactive position, Λrp), were compared to analyse the activation mechanisms. A characteristic reactive position isotope fractionation pattern was observed, distinct from aerobic degradation. Λrp values ranged from 10.5 to 11.8 for propane and from 7.8 to 9.4 for butane. Incubations of strain BuS5 with deuterium-labelled n-alkanes indicated that butane was activated solely at the subterminal C atom. In contrast, propane was activated mainly at the subterminal C atom but also significantly at the terminal C atoms. A conservative estimate suggests that about 70% of the propane activation events occurred at the subterminal C atom and about 30% at the terminal C atoms.

  15. Operando Raman spectroscopy study on the deactivation of Pt/Al2O3 and Pt-Sn/Al2O3 propane dehydrogenation catalysts.

    PubMed

    Sattler, Jesper J H B; Beale, Andrew M; Weckhuysen, Bert M

    2013-08-01

    The deactivation of 0.5 wt% Pt/Al2O3 and 0.5 wt% Pt-1.5 wt% Sn/Al2O3 catalysts has been studied by operando Raman spectroscopy during the dehydrogenation of propane and subsequent regeneration in air for 10 successive dehydrogenation-regeneration cycles. Furthermore, the reaction feed was altered by using different propane/propene/hydrogen ratios. It was found that the addition of hydrogen to the feed increases the catalyst performance and decreases the formation of coke deposits, as was revealed by thermogravimetrical analysis. The positive effect of hydrogen on the catalyst performance is comparable to the addition of Sn, a promoter element which increases both the propane conversion and propene selectivity. Operando Raman spectroscopy showed that hydrogen altered the nature of the coke deposits formed during propane dehydrogenation. Due to this approach it was possible to perform a systematic deconvolution procedure on the Raman spectra. By analysing the related intensity, band position and bandwidth of the different Raman features, it was determined that smaller graphite crystallites, which have less defects, are formed when the partial pressure of hydrogen in the feed was increased. PMID:23615824

  16. Highly sensitive and fast detection of propane-butane using a 3 μm quantum cascade laser.

    PubMed

    Jágerská, Jana; Tuzson, Béla; Looser, Herbert; Bismuto, Alfredo; Faist, Jérôme; Prinz, Heino; Emmenegger, Lukas

    2013-07-01

    A mid-IR optical analyzer based on a 3 μm Fabry-Perot quantum cascade laser has been developed for ultrafast detection of aerosol propellants, such as propane and butane. Given the laser emission bandwidth of 35 cm(-1), the system is spectrally well-matched to the C-H vibrational band of hydrocarbons, it is insusceptible to water interference, and stable enough to operate without wavelength scanning. Thus, it offers both high sensitivity and speed, reaching 1 ppm precision within a measurement time of 10 ms. The performance of the instrument is evaluated with an industrial demonstrator for aerosol cans leak testing, confirming that, in compliance with international directives, it can detect leaks of 1.2×10(-4) slpm at a rate of 500 cans per minute.

  17. 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. PMID:3537302

  18. Effect of supplementation of water vapor to the environmental characteristics of the combustion of propane-air mixture

    NASA Astrophysics Data System (ADS)

    Larionov, V. M.; Mitrofanov, G. A.; Iovleva, O. V.

    2014-11-01

    To improve the efficiency of combustion of fuel gas and air can be used additive steam. The article presents the results of an experimental study of the influence of water vapor on the combustion of propane-butane mixture with air. Combustion mixture produced in a modified Bunsen burner. Studies carried change of steam temperature of 180 to 260 degrees Celsius, and the change of the specific volume steam in the composition of the fuel mixture. Influence steam on combustion was estimated by the change of temperature of heating the quartz tube. It has been established that the increase of the steam temperature and increasing the specific volume of the heated vapor in the composition of the gaseous fuel increases the temperature of combustion.

  19. Effects of percentage of blockage and flameholder downstream counterbores on lean combustion limits of premixed, prevaporized propane-air mixture

    NASA Technical Reports Server (NTRS)

    Fernandez, M. A. B.

    1983-01-01

    Lean combustion limits were determined for a premixed prevaporized propane air mixture with flat plate flame stabilizers. Experiments were conducted in a constant area flame tube combustor utilizing flameholders of varying percentages of blockage and downstream counterbores. Combustor inlet air velocity at ambient conditions was varied from 4 to 9 meters per second. Flameholders with a center hole and four half holes surrounding it were tested with 63, 73, and 85 percent blockage and counterbore diameters of 112 and 125 percent of the thru hole diameter, in addition to the no counterbore configuration. Improved stability was obtained by using counterbore flameholders and higher percentages of blockage. Increases in mixture velocity caused the equivalence ratio at blowout to increase in all cases.

  20. Infinite dilution mutual diffusion coefficients of 1-octene and 1-tetradecane in near-critical ethane and propane

    SciTech Connect

    Noel, J.M.; Erkey, C.; Bukur, D.B.; Akgerman, A. . Chemical Engineering Dept.)

    1994-10-01

    The Fischer-Tropsch synthesis (FTS) is a method for converting synthesis gas into petroleum products such as gasoline and diesel fuel. The FTS can be carried out in the gas phase using fixed bed reactors or in the liquid phase in a slurry reactor. Effective pore diffusion is a rate-controlling phenomenon in both reactor types. The authors have utilized the Taylor dispersion technique to measure the infinite dilution mutual diffusion coefficients of 1-octene and 1-tetradecane in subcritical and supercritical ethane and in subcritical propane in the temperature range 293.15--338.15 K and the pressure range 5.52--11.03 MPa. For ethane, the measurements were done on either side of the critical temperature with the pressure above the critical pressure.