Science.gov

Sample records for fuel consumption reduction

  1. 77 FR 18718 - Petroleum Reduction and Alternative Fuel Consumption Requirements for Federal Fleets

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-28

    ... petroleum consumption and increase in alternative fuel consumption for Federal fleets (77 FR 14,482 (Mar. 12...; ] DEPARTMENT OF ENERGY 10 CFR Part 438 RIN 1904-AB98 Petroleum Reduction and Alternative Fuel Consumption... increase in alternative fuel consumption for Federal fleets. With this Request for Information (RFI),...

  2. Propulsion. [NASA program for aircraft fuel consumption reduction

    NASA Technical Reports Server (NTRS)

    Nored, D. L.

    1978-01-01

    NASA aims at developing propulsion technology to reduce the fuel consumption of present engines by 5%, that of new engines of the late 1980s by at least 12%, and that of an advanced early 1990s turboprop by an additional 15%. This paper reviews three separate NASA programs which take up these aims. They are, respectively, Engine Component Improvement, Energy Efficient Engine, and Advanced Turboprops.

  3. 75 FR 66008 - Fossil Fuel-Generated Energy Consumption Reduction for New Federal Buildings and Major...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-27

    ... Parts 433 and 435 RIN 1904-AB96 Fossil Fuel-Generated Energy Consumption Reduction for New Federal... proposed rulemaking (NOPR) regarding the fossil fuel- generated energy consumption ] requirements for new... Federal Register on October 15, 2010 (75 FR 63404), announcing a public meeting and seeking...

  4. Reduction of Fuel Consumption and Exhaust Pollutant Using Intelligent Transport Systems

    PubMed Central

    Nasir, Mostofa Kamal; Md Noor, Rafidah; Kalam, M. A.; Masum, B. M.

    2014-01-01

    Greenhouse gas emitted by the transport sector around the world is a serious issue of concern. To minimize such emission the automobile engineers have been working relentlessly. Researchers have been trying hard to switch fossil fuel to alternative fuels and attempting to various driving strategies to make traffic flow smooth and to reduce traffic congestion and emission of greenhouse gas. Automobile emits a massive amount of pollutants such as Carbon Monoxide (CO), hydrocarbons (HC), carbon dioxide (CO2), particulate matter (PM), and oxides of nitrogen (NOx). Intelligent transport system (ITS) technologies can be implemented to lower pollutant emissions and reduction of fuel consumption. This paper investigates the ITS techniques and technologies for the reduction of fuel consumption and minimization of the exhaust pollutant. It highlights the environmental impact of the ITS application to provide the state-of-art green solution. A case study also advocates that ITS technology reduces fuel consumption and exhaust pollutant in the urban environment. PMID:25032239

  5. Fuel Consumption Reduction and Weight Estimate of an Intercooled-Recuperated Turboprop Engine

    NASA Astrophysics Data System (ADS)

    Andriani, Roberto; Ghezzi, Umberto; Ingenito, Antonella; Gamma, Fausto

    2012-09-01

    The introduction of intercooling and regeneration in a gas turbine engine can lead to performance improvement and fuel consumption reduction. Moreover, as first consequence of the saved fuel, also the pollutant emission can be greatly reduced. Turboprop seems to be the most suitable gas turbine engine to be equipped with intercooler and heat recuperator thanks to the relatively small mass flow rate and the small propulsion power fraction due to the exhaust nozzle. However, the extra weight and drag due to the heat exchangers must be carefully considered. An intercooled-recuperated turboprop engine is studied by means of a thermodynamic numeric code that, computing the thermal cycle, simulates the engine behavior at different operating conditions. The main aero engine performances, as specific power and specific fuel consumption, are then evaluated from the cycle analysis. The saved fuel, the pollution reduction, and the engine weight are then estimated for an example case.

  6. Reduction in Energy Consumption for Pretreatment Process and Transportation of Pulverized Wood Fuel

    NASA Astrophysics Data System (ADS)

    Nishi, Kenji; Sawai, Toru; Ohmasa, Mitsushi; Hirokawa, Noriyasu; Shibue, Tadashi; Kajimoto, Takeshi

    In recent years, much attention has been focused on the energy utilization of biomass to reduce the emission of greenhouse gas. Especially, woody biomass such as the forestry biomass derived from logging and thinning operations in forests is one of the most promising domestic resources in Japan. Woody biomass contributes not only to the improvement of energy self-sufficiency in Japan, but also to the environmental protection of Japanese forests. When the woody biomass is utilized, it is necessary to examine the energy consumption for collection of resources, pretreatment, transportation and after-treatment. In the present study, woody biomass is assumed to be utilized as pulverized wood fuel in local area. The pretreatment of pulverized wood fuel is consisted of three procedures; drying, semi-carbonizaion and fine comminution. The main purpose of the study is to investigate the comminution characteristic of the Japanese cedar thinning and the reduction in energy consumption for pretreatment process and transportation of pulverized wood fuel. The results obtained in the present study are as follows. (1) Comminution energy increases as the water content increases and the sieve of screen becomes small. The comminution energy of hammer mill is largely affected by the water content. Difference in comminution energy between the hammer and cutter mills is large. The ratio of comminution energy of the hammer mill to that of the cutter mill exceeds 10 for the water content of 40% and sieve of screen of 3mm. (2) To estimate the comminution energy of woody biomass, empirical equations of work index in Bond's Law are presented. In woody biomass region, the empirical equations of work index depend on the comminution method. In semi-carbonization and carbonization regions, the empirical equation of work index is presented regardless of comminution method and sieve of screen. The comminution energy can be estimated by using the present empirical equations within accuracy ±50

  7. Reduction of aerodynamic drag and fuel consumption for tractor-trailer vehicles

    NASA Technical Reports Server (NTRS)

    Muirhead, V. U.; Saltzman, E. J.

    1979-01-01

    Wind-tunnel tests were performed on a scale model of a cab-over-engine tractor-trailer vehicle and several modifications of the model. Results from two of the model configurations were compared with full-scale drag data obtained from similar configurations during coast-down tests. Reductions in fuel consumption derived from these tests are presented in terms of fuel quantity and dollar savings per vehicle year, based on an annual driving distance of 160,900 km (100,000 mi.). The projected savings varied from 13,001 (3435) to 25,848 (6829) liters (gallons) per year which translated to economic savings from $3435 to about $6829 per vehicle year for an operating speed of 88.5 km/h (55 mph) and wind speeds near the national average of 15.3 km/h (9.5 mph). The estimated cumulative fuel savings for the entire U.S. fleet of cab-over-engine tractor, van-type trailer combinations ranged from 4.18 million kl (26.3 million bbl) per year for a low-drag configuration to approximately twice that amount for a more advanced configuration.

  8. Reductions in vehicle fuel consumption due to refinements in aerodynamic design. [for trailer trucks

    NASA Technical Reports Server (NTRS)

    Saltzman, E. J.

    1979-01-01

    Over-the-highway fuel consumption and coastdown drag tests were performed on cab-over-engine, van type trailer trucks and modifications of these vehicles incorporating refinements in aerodynamic design. In addition, 1/25-scale models of these configurations, and derivatives of these configurations were tested in a wind tunnel to determine the effects of wind on the magnitude of the benefits that aerodynamic refinements can provide. The results of these tests are presented for a vehicle incorporating major redesign features and for a relatively simple add-on modification. These results include projected fuel savings on the basis of annual savings per vehicle year as well as probable nationwide fuel savings.

  9. Amtrak fuel consumption study

    SciTech Connect

    Hitz, J.

    1981-02-01

    This report documents a study of fuel consumption on National Railroad Passenger Corporation (Amtrak) trains and is part of an effort to determine effective ways of conserving fuel on the Amtrak system. The study was performed by the Transportation Systems Center (TSC). A series of 26 test runs were conducted on Amtrak trains operating between Boston, Massachusetts, and New Haven, Connecticut, to measure fuel consumption, trip time and other fuel-use-related parameters. The test data were analyzed and compared with results of the TSC Train Performance Simulator replicating the same operations.

  10. 77 FR 14482 - Petroleum Reduction and Alternative Fuel Consumption Requirements for Federal Fleets

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-12

    ..., including but not limited to hybrid electric vehicles, LSEVs, electric vehicles, and plug-in hybrid electric... fuel economy through the acquisition of smaller-sized vehicles ] and/or hybrid, electric, or other..., ``Strengthening Federal Environmental, Energy, and Transportation Management,'' 72 FR 3919 (Jan. 26, 2007), and...

  11. Fuel reduction and electricity consumption impact of different charging scenarios for plug-in hybrid electric vehicles

    NASA Astrophysics Data System (ADS)

    Zhang, Li; Brown, Tim; Samuelsen, G. Scott

    2011-08-01

    Plug-in hybrid electric vehicles (PHEVs) consume both gasoline and grid electricity. The corresponding temporal energy consumption and emission trends are valuable to investigate in order to fully understand the environmental benefits. The 24-h energy consumption and emission profile depends on different vehicle designs, driving, and charging scenarios. This study assesses the potential energy impact of PHEVs by considering different charging scenarios defined by different charging power levels, locations, and charging time. The region selected for the study is the South Coast Air Basin of California. Driving behaviors are derived from the National Household Travel Survey 2009 (NHTS 2009) and vehicle parameters are based on realistic assumptions consistent with projected vehicle deployments. Results show that the reduction in petroleum consumption is significant compared to standard gasoline vehicles and the ability to operate on electricity alone is crucial to cold start emission reduction. The benefit of higher power charging on petroleum consumption is small. Delayed and average charging are better than immediate charging for home, and non-home charging increases peak grid loads.

  12. Fuel consumption in optimal control

    NASA Technical Reports Server (NTRS)

    Redmond, Jim; Silverberg, Larry

    1992-01-01

    A method has been developed for comparing three optimal control strategies based on fuel consumption. A general cost function minimization procedure was developed by applying two theorems associated with convex sets. Three cost functions associated with control saturation, pseudofuel, and absolute fuel are introduced and minimized. The first two cost functions led to the bang-bang and continuous control strategies, and the minimization of absolute fuel led to an impulsive strategy. The three control strategies were implemented on two elementary systems and a comparison of fuel consumption was made. The impulse control strategy consumes significantly less fuel than the continuous and bang-bang control strategies. This comparison suggests a potential for fuel savings in higher-order systems using impulsive control strategies. However, since exact solutions to fuel-optimal control for large-order systems are difficult if not impossible to achieve, the alternative is to develop near-optimal control strategies.

  13. 10 CFR 490.804 - Eligible reductions in petroleum consumption.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Eligible reductions in petroleum consumption. 490.804 Section 490.804 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Compliance § 490.804 Eligible reductions in petroleum consumption. (a) Motor...

  14. 10 CFR 490.804 - Eligible reductions in petroleum consumption.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Eligible reductions in petroleum consumption. 490.804 Section 490.804 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Compliance § 490.804 Eligible reductions in petroleum consumption. (a) Motor...

  15. 10 CFR 490.804 - Eligible reductions in petroleum consumption.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Section 490.804 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Compliance § 490.804 Eligible reductions in petroleum consumption. (a) Motor vehicles... person are applicable towards the petroleum fuel reduction required in § 490.803(a) of this subpart....

  16. 10 CFR 490.804 - Eligible reductions in petroleum consumption.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Section 490.804 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Compliance § 490.804 Eligible reductions in petroleum consumption. (a) Motor vehicles... person are applicable towards the petroleum fuel reduction required in § 490.803(a) of this subpart....

  17. 10 CFR 490.804 - Eligible reductions in petroleum consumption.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Section 490.804 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Compliance § 490.804 Eligible reductions in petroleum consumption. (a) Motor vehicles... person are applicable towards the petroleum fuel reduction required in § 490.803(a) of this subpart....

  18. CF6 jet engine performance improvement program. Short core exhaust nozzle performance improvement concept. [specific fuel consumption reduction

    NASA Technical Reports Server (NTRS)

    Fasching, W. A.

    1979-01-01

    The short core exhaust nozzle was evaluated in CF6-50 engine ground tests including performance, acoustic, and endurance tests. The test results verified the performance predictions from scale model tests. The short core exhaust nozzle provides an internal cruise sfc reduction of 0.9 percent without an increase in engine noise. The nozzle hardware successfully completed 1000 flight cycles of endurance testing without any signs of distress.

  19. Predicting ship fuel consumption: Update. Technical report

    SciTech Connect

    Schrady, D.A.; Smyth, G.K.; Vassian, R.B.

    1996-07-01

    This report is concerned with the prediction of ship propulsion fuel consumption as a function of ship speed for U.S. Navy combatant and auxiliary ships. Prediction is based on fitting an analytic function to published ship class speed-fuel use data using nonlinear regression. The form of the analytic function fitted is motivated by the literature on ship powering and resistance. The report discusses data sources and data issues, and the impact of ship propulsion plant configuration on fuel use. The regression coefficients of the exponential function fitted, tabular numerical comparison of predicted and actual fuel use data, the standard error of the estimate, and plots of actual and fitted data are given for 22 classes of Navy ships.

  20. Fuel Savings and Emission Reductions from Next-Generation Mobile Air Conditioning Technology in India: Preprint

    SciTech Connect

    Chaney, L.; Thundiyil, K.; Chidambaram, S.; Abbi, Y. P.; Anderson, S.

    2007-05-01

    This paper quantifies the mobile air-conditioning fuel consumption of the typical Indian vehicle, exploring potential fuel savings and emissions reductions these systems for the next generation of vehicles.

  1. Reduced truck fuel consumption through aerodynamic design

    NASA Technical Reports Server (NTRS)

    Steers, L. L.; Saltzman, E. J.

    1977-01-01

    Full-scale fuel consumption and drag tests were performed on a conventional cab-over-engine tractor-trailer combination and a version of the same vehicle with significant forebody modifications. The modified configuration had greatly increased radii on all front corners and edges of the tractor and a smooth fairing of the modified tractor top and sides extending to the trailer. Concurrent highway testing of the two configurations showed that the modified design used 20% to 24% less fuel than the baseline configuration at 88.5 km/hr (55 mph) with near-calm wind conditions. Coastdown test results showed that the modified configuration reduced the drag coefficient by 0.43 from the baseline value of 1.17 at 88.5 km/hr (55 mph) in calm wind conditions.

  2. Fuel consumption improvement in current transport engines

    NASA Technical Reports Server (NTRS)

    Hines, R. W.; Ziemianski, J. A.

    1978-01-01

    A review is conducted of improvements which can be made with respect to the fuel consumption of current engines and new production versions of current engines. A description is presented of an engine diagnostics program which has the objective to identify and quantify the causes and sources of performance deterioration in the JT9D turbofan engine and to develop basic data which will be applied to minimize performance degradation of current and future engines. General areas where performance losses occur are examined, taking into account seals, blades and vanes, and cases. Potential performance improvement concepts are related to improved component aerodynamics, improved flowpath sealing, blade tip clearance control, improved turbine cooling effectiveness, improved turbine materials and coatings, duct and nozzle aerodynamic refinements, nacelle aerodynamic refinements, forced exhaust mixers, advanced nacelle materials, and advanced fuel control.

  3. Fuel Savings and Aerodynamic Drag Reduction from Rail Car Covers

    NASA Technical Reports Server (NTRS)

    Storms, Bruce; Salari, Kambiz; Babb, Alex

    2008-01-01

    The potential for energy savings by reducing the aerodynamic drag of rail cars is significant. A previous study of aerodynamic drag of coal cars suggests that a 25% reduction in drag of empty cars would correspond to a 5% fuel savings for a round trip [1]. Rail statistics for the United States [2] report that approximately 5.7 billion liters of diesel fuel were consumed for coal transportation in 2002, so a 5% fuel savings would total 284 million liters. This corresponds to 2% of Class I railroad fuel consumption nationwide. As part of a DOE-sponsored study, the aerodynamic drag of scale rail cars was measured in a wind tunnel. The goal of the study was to measure the drag reduction of various rail-car cover designs. The cover designs tested yielded an average drag reduction of 43% relative to empty cars corresponding to an estimated round-trip fuel savings of 9%.

  4. Machining strategies exploring reduction in energy consumption

    NASA Astrophysics Data System (ADS)

    Mamun, Abdullah Al

    The main aim of this thesis is to explore machining strategies, analyzing energy consumption using Design of Experiments (DOE) at the material removal rate (MRR), compare to cutting geometrical trajectories according to CNC parameters such as spindle RPM, feed rate, depth of cut per pass and total depth of cut. Spindle RPM, depth of cut per pass, and feed rate are selected as the main three factors and each factor has two levels: low-level (-) and high-level (+). These experiments have been performed at an end-milling machine by using a concept of a constant volume of material removal processes in the circular and linear geometrical slots in pine wood blocks. Standard energy logger equipment has used to measure energy consumption during end-milling operation. Different statistical analysis, such as ANOVA, regression line, and cause & effect diagram have used to show different energy consumption results in the material removal process. At the end the of data analysis, it is found that a significant amount of electricity demand is associated with machining pre-cutting & post-cutting stage and this significant amount of electricity demand is defined as peripheral energy. This peripheral energy is not involved in the actual performance of material removal process in the end-milling process. In the [Figure 11] end-milling process has been involved with pine wood blocks at constant volume of material removal (2.8 cubic inch) process. Results can be varied using of hard material removal process, such as steel & aluminum metals.

  5. Life Cycle Assessment of Vehicle Lightweighting: Novel Mathematical Methods to Estimate Use-Phase Fuel Consumption.

    PubMed

    Kim, Hyung Chul; Wallington, Timothy J; Sullivan, John L; Keoleian, Gregory A

    2015-08-18

    Lightweighting is a key strategy to improve vehicle fuel economy. Assessing the life-cycle benefits of lightweighting requires a quantitative description of the use-phase fuel consumption reduction associated with mass reduction. We present novel methods of estimating mass-induced fuel consumption (MIF) and fuel reduction values (FRVs) from fuel economy and dynamometer test data in the U.S. Environmental Protection Agency (EPA) database. In the past, FRVs have been measured using experimental testing. We demonstrate that FRVs can be mathematically derived from coast down coefficients in the EPA vehicle test database avoiding additional testing. MIF and FRVs calculated for 83 different 2013 MY vehicles are in the ranges 0.22-0.43 and 0.15-0.26 L/(100 km 100 kg), respectively, and increase to 0.27-0.53 L/(100 km 100 kg) with powertrain resizing to retain equivalent vehicle performance. We show how use-phase fuel consumption can be estimated using MIF and FRVs in life cycle assessments (LCAs) of vehicle lightweighting from total vehicle and vehicle component perspectives with, and without, powertrain resizing. The mass-induced fuel consumption model is illustrated by estimating lifecycle greenhouse gas (GHG) emission benefits from lightweighting a grille opening reinforcement component using magnesium or carbon fiber composite for 83 different vehicle models. PMID:26168234

  6. Steam consumption reduction by eutectic freeze crystallization

    SciTech Connect

    Bichsel, S.E.; Cleary, M.; Barron, T.S.; Heist, J.A.

    1985-01-01

    Steam production in American beet sugar factories can be reduced by 600 pounds per ton of beets by using hydrate freeze crystallization in place of pan evaporators for sugar crystallization. This is a relatively constant number, regardless of current factory energy use. Further reduction is limited by the juice heating needs in the purification operations. Steam for juice heating is 20 to 30% on beets, or 400 to 600 pounds of steam per ton. In efficient factories this is about the steam flow to the evaporators when the pan crystallizers are replaced by freeze crystallization. An approach is described here for a rapid evaluation of effects on the steam balance of basic process changes. It provides a visual guide to restructuring the steam balance that simplifies optimization when such changes are made. The graphic approach is useful in illustrating methods of reducing energy use in a sugar factory, in addition to the current analysis of integration of the hydrate freeze process. For example, membrane and vapor recompression evaporators for juice concentration must be accompanied by major factory modifications to produce any net savings of steam. The reason is the needs for specific steam quantity and quality for the pan evaporators and juice heaters, supplied through the current evaporator trains. Reduction of the steam rate below 25 to 35% on beets will require changes to the conventional juice purification process.

  7. FTFc52 - freight train fuel consumption computer program. Software

    SciTech Connect

    Koper, J.; Muhlenberg, J.D.

    1980-09-01

    This tape contains a copy of a computer program for the prediction of fuel consumption of a freight train operated over track with known characteristics. The program is written in FORTRAN for the IBM VM/370 computer.

  8. New approach for reduction of diesel consumption by comparing different mining haulage configurations.

    PubMed

    Rodovalho, Edmo da Cunha; Lima, Hernani Mota; de Tomi, Giorgio

    2016-05-01

    The mining operations of loading and haulage have an energy source that is highly dependent on fossil fuels. In mining companies that select trucks for haulage, this input is the main component of mining costs. How can the impact of the operational aspects on the diesel consumption of haulage operations in surface mines be assessed? There are many studies relating the consumption of fuel trucks to several variables, but a methodology that prioritizes higher-impact variables under each specific condition is not available. Generic models may not apply to all operational settings presented in the mining industry. This study aims to create a method of analysis, identification, and prioritization of variables related to fuel consumption of haul trucks in open pit mines. For this purpose, statistical analysis techniques and mathematical modelling tools using multiple linear regressions will be applied. The model is shown to be suitable because the results generate a good description of the fuel consumption behaviour. In the practical application of the method, the reduction of diesel consumption reached 10%. The implementation requires no large-scale investments or very long deadlines and can be applied to mining haulage operations in other settings. PMID:26946166

  9. Treatment of alcohol dependence: recent progress and reduction of consumption.

    PubMed

    Testino, G; Leone, S; Borro, P

    2014-12-01

    Alcohol dependence (AD) is a major public health problem. Currently, three drugs for the treatment of AD have been approved by both the European Medicines Agency (EMA) and the Food and Drug Administration (FDA): acamprosate, disulfiram, and oral naltrexone. The FDA also approved the use of long-acting injectable naltrexone. In Austria and in Italy sodium oxybate is also approved. The EMA's Committee for Medicinal Products for Human Use has recently granted marketing authorization for nalmefene for the reduction of alcohol consumption. Many patients, while accepting the problem, are unable or unwilling to completely stop consuming alcohol, leading to an inevitable deterioration over time of their psycho-physical state, and social and family relationships. It is appropriate to offer these patients the opportunity to significantly reduce their consumption of alcohol. The reduction may be an opportunity to prepare the individual for achieving complete abstinence. Abstinence should always be the main goal. Currently, nalmefene is the only drug that has been authorized for the reduction of alcohol consumption. Its association with psycho-social support is mandatory; it is taken on an "as-needed" basis, which should preferably be 1-2 hours before the possible intake of alcohol. The trials showed a significant reduction in alcohol consumption, which resulted in a significant reduction in morbidity and mortality. Reducing consumption allows a decrease in the progression of numerous alcohol-induced chronic diseases, as well as a reduction in psycho-physical damage, acts of violence, motor vehicle accidents, and accidents at work, which in turn means fewer healthcare costs. PMID:25392958

  10. Experimental characterization of cooled EGR in a gasoline direct injection engine for reducing fuel consumption and nitrogen oxide emission

    NASA Astrophysics Data System (ADS)

    Park, Sang-Ki; Lee, Jungkoo; Kim, Kyungcheol; Park, Seongho; Kim, Hyung-Man

    2015-11-01

    The emphasis on increasing fuel economy and reducing emissions is increasing. Attention has turned to how the performance of a gasoline direct injection (GDI) engine can be improved to achieve lower fuel consumption and NOx emission. Therefore, positive effects can reduce fuel consumption and NOx emission as well as knock suppression. The cooled exhaust gas recirculation (EGR) ranges within the characteristic map are characterized from the experimental results at various speeds and brake mean effective pressures in a GDI engine. The results show that the application of cooled EGR system brought in 3.63 % reduction as for the fuel consumption and 4.34 % as for NOx emission.

  11. Issues of fish consumption for cardiovascular disease risk reduction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing fish consumption is recommended for intake of omega-3 (n-3) fatty acids and to confer benefits for the risk reduction of cardiovascular disease (CVD). Most Americans are not achieving intake levels that comply with current recommendations. It is the goal of this review to provide an overv...

  12. Engine component improvement program: Performance improvement. [fuel consumption

    NASA Technical Reports Server (NTRS)

    Mcaulay, J. E.

    1979-01-01

    Fuel consumption of commercial aircraft is considered. Fuel saving and retention components for new production and retrofit of JT9D, JT8D, and CF6 engines are reviewed. The manner in which the performance improvement concepts were selected for development and a summary of the current status of each of the 16 selected concepts are discussed.

  13. Jet transport energy management for minimum fuel consumption and noise impact in the terminal area

    NASA Technical Reports Server (NTRS)

    Bull, J. S.; Foster, J. D.

    1974-01-01

    Significant reductions in both noise and fuel consumption can be gained through careful tailoring of approach flightpath and airspeed profile, and the point at which the landing gear and flaps are lowered. For example, the noise problem has been successfully attacked in recent years with development of the 'two-segment' approach, which brings the aircraft in at a steeper angle initially, thereby achieving noise reduction through lower thrust settings and higher altitudes. A further reduction in noise and a significant reduction in fuel consumption can be achieved with the 'decelerating approach' concept. In this case, the approach is initiated at high airspeed and in a drag configuration that allows for low thrust. The landing flaps are then lowered at the appropriate time so that the airspeed slowly decelerates to V sub r at touchdown. The decelerating approach concept can be applied to constant glideslope flightpaths or segmented flightpaths such as the two-segment approach.

  14. Estimating vehicle fuel consumption in urban areas. Working paper

    SciTech Connect

    Ferreira, L.J.A.

    1981-01-01

    Traffic flow simulation and assignment techniques were used to model area-wide effects of traffic management measures. Relationships between fuel consumption under urban driving conditions and the inverse of average travel speed were inferred from experimental tests. From the results a relationship which gave urban fuel consumption as a function of journey distance, total delayed time, and number of stops, was suggested for the 'average urban passenger car' in the UK. A review of reported potential fuel savings from traffic management measures was also undertaken. The effects on fuel consumption of changing the common cycle time for a co-ordinated system of signalised intersections were evaluated using the SATURN traffic simulation/assignment model.

  15. Measured effect of wind generation on the fuel consumption of an isolated diesel power system

    NASA Technical Reports Server (NTRS)

    Stiller, P. H.; Scott, G. W.; Shaltens, R. K.

    1983-01-01

    The Block Island Power Company (BIPCO), on Block Island, Rhode Island, operates an isolated electric power system consisting of diesel generation and an experimental wind turbine. The 150-kW wind turbine, designated MOD-OA by the U.S. Department of Energy is typically operated in parallel with two diesel generators to serve an average winter load of 350 kW. Wind generation serves up to 60 percent of the system demand depending on wind speed and total system load. Results of diesel fuel consumption measurements are given for the diesel units operated in parallel with the wind turbine and again without the wind turbine. The fuel consumption data are used to calculate the amount of fuel displaced by wind energy. Results indicate that the wind turbine displaced 25,700 lbs. of the diesel fuel during the test period, representing a calculated reduction in fuel consumption of 6.7 percent while generating 11 percent of the total electric energy. The amount of displaced fuel depends on operating conditions and system load. It is also shown that diesel engine throttle activity resulting from wind gusts which rapidly change the wind turbine output do not significantly influence fuel consumption.

  16. Tracked-vehicle fuel consumption. Final report

    SciTech Connect

    Not Available

    1987-03-06

    This document describes test procedures for evaluating the fuel efficiency of tracked vehicles under controlled operating conditions. The test data are a major source for comparisons with similar vehicles, and can also serve to predict the operational range of these vehicles during tactical missions.

  17. Issues of fish consumption for cardiovascular disease risk reduction.

    PubMed

    Raatz, Susan K; Silverstein, Jeffrey T; Jahns, Lisa; Picklo, Matthew J

    2013-04-01

    Increasing fish consumption is recommended for intake of omega-3 (n-3) fatty acids and to confer benefits for the risk reduction of cardiovascular disease (CVD). Most Americans are not achieving intake levels that comply with current recommendations. It is the goal of this review to provide an overview of the issues affecting this shortfall of intake. Herein we describe the relationship between fish intake and CVD risk reduction as well as the other nutritional contributions of fish to the diet. Currently recommended intake levels are described and estimates of fish consumption at a food disappearance and individual level are reported. Risk and benefit factors influencing the choice to consume fish are outlined. The multiple factors influencing fish availability from global capture and aquaculture are described as are other pertinent issues of fish nutrition, production, sustainability, and consumption patterns. This review highlights some of the work that needs to be carried out to meet the demand for fish and to positively affect intake levels to meet fish intake recommendations for CVD risk reduction. PMID:23538940

  18. Fuel Consumption and Emissions from Airport Taxi Operations

    NASA Technical Reports Server (NTRS)

    Jung, Yoon

    2010-01-01

    Developed a method to calculate fuel consumption and emissions of phases of taxi operations. Results at DFW showed that up to 18% of fuel can be saved by eliminating stop-and-go situations. Developed an energy efficient and environmentally friendly surface concept: Spot and Runway Departure Advisory (SARDA) tool. The SARDA tool has been identified as a potential candidate for a technology transfer to the FAA.

  19. Nonresidential buildings energy consumption survey: 1979 consumption and expenditures. Part 2. Steam, fuel oil, LPG, and all fuels

    SciTech Connect

    Patinkin, L.

    1983-12-01

    This report presents data on square footage and on total energy consumption and expenditures for commercial buildings in the contiguous United States. Also included are detailed consumption and expenditures tables for fuel oil or kerosene, liquid petroleum gas (LPG), and purchased steam. Commercial buildings include all nonresidential buildings with the exception of those where industrial activities occupy more of the total square footage than any other type of activity. 7 figures, 23 tables.

  20. Impact of source segregation intensity of solid waste on fuel consumption and collection costs.

    PubMed

    Di Maria, Francesco; Micale, Caterina

    2013-11-01

    Fuel consumption and collection costs of solid waste were evaluated by the aid of a simulation model for a given collection area of a medium-sized Italian city. Using the model it is possible to calculate time, collected waste and fuel consumption for a given waste collection route. Starting from the data for the current waste collection scenario with a Source Segregated (SS) intensity of 25%, all the main model error evaluated was ⩽1.2. SS intensity scenarios of 25%, 30%, 35% and 52% were simulated. Results showed an increase in the average fuel consumed by the collection vehicles that went from about 3.3L/tonne for 25% SS intensity to about 3.8L/tonne for a SS intensity of 52%. Direct collection costs, including crews and vehicle purchase, ranged from about 40€/tonne to about 70€/tonne, respectively, for 25% and 52% SS intensity. The increase in fuel consumption and collection costs depends on the density of the waste collected, on the collection vehicle compaction ratio and on the waste collection vehicle utilization factor (WCVUF). In particular a reduction of about 50% of the WCVUF can lead to an average increase of about 80% in fuel consumption and 100% in collection costs. PMID:23871186

  1. Concepts for reducing exhaust emissions and fuel consumption of the aircraft piston engine

    NASA Technical Reports Server (NTRS)

    Rezy, B. J.; Stuckas, K. J.; Tucker, J. R.; Meyers, J. E.

    1979-01-01

    A study was made to reduce exhaust emissions and fuel consumption of a general aviation aircraft piston engine by applying known technology. Fourteen promising concepts such as stratified charge combustion chambers, cooling cylinder head improvements, and ignition system changes were evaluated for emission reduction and cost effectiveness. A combination of three concepts, improved fuel injection system, improved cylinder head with exhaust port liners and exhaust air injection was projected as the most cost effective and safe means of meeting the EPA standards for CO, HC and NO. The fuel economy improvement of 4.6% over a typical single engine aircraft flight profile does not though justify the added cost of the three concepts, and significant reductions in fuel consumption must be applied to the cruise mode where most of the fuel is used. The use of exhaust air injection in combination with exhaust port liners reduces exhaust valve stem temperatures which can result in longer valve guide life. The use of exhaust port liners alone can reduce engine cooling air requirements by 11% which is the equivalent of a 1.5% increase in propulsive power. The EPA standards for CO, HC and NO can be met in the IO-520 engine using air injection alone or the Simmonds improved fuel injection system.

  2. 78 FR 37883 - Information Collection Activities: Report of Fuel Cost, Consumption, and Surcharge Revenue

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-24

    ...As required by the Paperwork Reduction Act of 1995, 44 U.S.C. 3501-3519 (PRA), the Surface Transportation Board (STB or Board) gives notice of its intent to seek from the Office of Management and Budget (OMB) an extension of approval for the collection of the Report of Fuel Cost, Consumption, and Surcharge Revenue. Comments are requested concerning: (1) The accuracy of the Board's burden......

  3. Device for reducing fuel consumption in internal combustion engines

    SciTech Connect

    Sverdlin, A.

    1981-04-21

    An internal combustion engine is provided with a device for automatically preventing thermal and mechanical stress during overload periods, and to power the engine with the most economical fuel consumption rate possible. In a preferred embodiment, the device is associated with the variable speed governor of the main diesel engine of a ship. The device includes a system actuated by significant movements of the governor to regulate the fuel pump or pumps or reduce the engine speed to a more economical and safe level. Means for overriding the system in emergency situations may be provided.

  4. Capacity utilization and fuel consumption in the electric power industry, 1970-1981

    SciTech Connect

    Lewis, E.W.

    1982-07-01

    This report updates the 1980 Energy Information Administration (EIA) publication entitled Trends in the Capacity Utilization and Fuel Consumption of Electric Utility Powerplants, 1970-1978, DOE/EIA-184/32. The analysis covers the period from 1970 through 1981, and examines trends during the period prior to the 1973 Arab oil embargo (1970-1973), after the embargo (1974-1977), and during the immediate past (1978-1981). The report also addresses other factors affecting the electric utility industry since the oil embargo: the reduction in foreign oil supplies as a result of the 1979 Iranian crisis, the 1977 drought in the western United States, the 1978 coal strike by the United Mine Workers Union, and the shutdown of nuclear plants in response to the accident at Three Mile Island. Annual data on electric utility generating capacity, net generation, and fuel consumption are provided to identify changes in patterns of power plant capacity utilization and dispatching.

  5. RECENT TRENDS IN EMERGING TRANSPORTATION FUELS AND ENERGY CONSUMPTION

    SciTech Connect

    Bunting, Bruce G

    2012-01-01

    Abundance of energy can be improved both by developing new sources of fuel and by improving efficiency of energy utilization, although we really need to pursue both paths to improve energy accessibility in the future. Currently, 2.7 billion people or 38% of the world s population do not have access to modern cooking fuel and depend on wood or dung and 1.4 billion people or 20% do not have access to electricity. It is estimated that correcting these deficiencies will require an investment of $36 billion dollars annually through 2030. In growing economies, energy use and economic growth are strongly linked, but energy use generally grows at a lower rate due to increased access to modern fuels and adaptation of modern, more efficient technology. Reducing environmental impacts of increased energy consumption such as global warming or regional emissions will require improved technology, renewable fuels, and CO2 reuse or sequestration. The increase in energy utilization will probably result in increased transportation fuel diversity as fuels are shaped by availability of local resources, world trade, and governmental, environmental, and economic policies. The purpose of this paper is to outline some of the recently emerging trends, but not to suggest winners. This paper will focus on liquid transportation fuels, which provide the highest energy density and best match with existing vehicles and infrastructure. Data is taken from a variety of US, European, and other sources without an attempt to normalize or combine the various data sources. Liquid transportation fuels can be derived from conventional hydrocarbon resources (crude oil), unconventional hydrocarbon resources (oil sands or oil shale), and biological feedstocks through a variety of biochemical or thermo chemical processes, or by converting natural gas or coal to liquids.

  6. Cost-Optimal Pathways to 75% Fuel Reduction in Remote Alaskan Villages: Preprint

    SciTech Connect

    Simpkins, Travis; Cutler, Dylan; Hirsch, Brian; Olis, Dan; Anderson, Kate

    2015-10-28

    There are thousands of isolated, diesel-powered microgrids that deliver energy to remote communities around the world at very high energy costs. The Remote Communities Renewable Energy program aims to help these communities reduce their fuel consumption and lower their energy costs through the use of high penetration renewable energy. As part of this program, the REopt modeling platform for energy system integration and optimization was used to analyze cost-optimal pathways toward achieving a combined 75% reduction in diesel fuel and fuel oil consumption in a select Alaskan village. In addition to the existing diesel generator and fuel oil heating technologies, the model was able to select from among wind, battery storage, and dispatchable electric heaters to meet the electrical and thermal loads. The model results indicate that while 75% fuel reduction appears to be technically feasible it may not be economically viable at this time. When the fuel reduction target was relaxed, the results indicate that by installing high-penetration renewable energy, the community could lower their energy costs by 21% while still reducing their fuel consumption by 54%.

  7. Cost-Optimal Pathways to 75% Fuel Reduction in Remote Alaskan Villages

    SciTech Connect

    Simpkins, Travis; Cutler, Dylan; Hirsch, Brian; Olis, Dan; Anderson, Kate

    2015-08-01

    There are thousands of isolated, diesel-powered microgrids that deliver energy to remote communities around the world at very high energy costs. The Remote Communities Renewable Energy program aims to help these communities reduce their fuel consumption and lower their energy costs through the use of high penetration renewable energy. As part of this program, the REopt modeling platform for energy system integration and optimization was used to analyze cost-optimal pathways toward achieving a combined 75% reduction in diesel fuel and fuel oil consumption in a select Alaskan village. In addition to the existing diesel generator and fuel oil heating technologies, the model was able to select from among wind, battery storage, and dispatchable electric heaters to meet the electrical and thermal loads. The model results indicate that while 75% fuel reduction appears to be technically feasible it may not be economically viable at this time. When the fuel reduction target was relaxed, the results indicate that by installing high-penetration renewable energy, the community could lower their energy costs by 21% while still reducing their fuel consumption by 54%.

  8. Transportation Energy Futures: Combining Strategies for Deep Reductions in Energy Consumption and GHG Emissions (Brochure)

    SciTech Connect

    Not Available

    2013-03-01

    This fact sheet summarizes actions in the areas of light-duty vehicle, non-light-duty vehicle, fuel, and transportation demand that show promise for deep reductions in energy use. Energy efficient transportation strategies have the potential to simultaneously reduce oil consumption and greenhouse gas (GHG) emissions. The Transportation Energy Futures (TEF) project examined how the combination of multiple strategies could achieve deep reductions in GHG emissions and petroleum use on the order of 80%. Led by NREL, in collaboration with Argonne National Laboratory, the project's primary goal was to help inform domestic decisions about transportation energy strategies, priorities, and investments, with an emphasis on underexplored opportunities. TEF findings reveal three strategies with the potential to displace most transportation-related petroleum use and GHG emissions: 1) Stabilizing energy use in the transportation sector through efficiency and demand-side approaches. 2) Using additional advanced biofuels. 3) Expanding electric drivetrain technologies.

  9. Effect Of Platooning on Fuel Consumption of Class 8 Vehicles Over a Range of Speeds, Following Distances, and Mass

    SciTech Connect

    Lammert, M. P.; Duran, A.; Diez, J.; Burton, K.; Nicholson, A.

    2014-10-01

    This research project evaluates fuel consumption results of two Class 8 tractor-trailer combinations platooned together compared to their standalone fuel consumption. A series of ten modified SAE Type II J1321 fuel consumption track tests were performed to document fuel consumption of two platooned vehicles and a control vehicle at varying steady-state speeds, following distances, and gross vehicle weights (GVWs). The steady-state speeds ranged from 55 mph to 70 mph, the following distances ranged from a 20-ft following distance to a 75-ft following distance, and the GVWs were 65K lbs and 80K lbs. All tractors involved had U.S. Environmental Protection Agency (EPA) SmartWay-compliant aerodynamics packages installed, and the trailers were equipped with side skirts. Effects of vehicle speed, following distance, and GVW on fuel consumption were observed and analyzed. The platooning demonstration system used in this study consisted of radar systems, Dedicated Short-Range Communication (DSRC) vehicle-to-vehicle (V2V) communications, vehicle braking and torque control interface, cameras and driver displays. The lead tractor consistently demonstrated an improvement in average fuel consumption reduction as following distance decreased, with results showing 2.7% to 5.3% fuel savings at a GVW of 65k. The trailing vehicle achieved fuel consumption savings ranging from 2.8% to 9.7%; tests during which the engine cooling fan did not operate achieved savings of 8.4% to 9.7%. 'Team' fuel savings, considering the platooned vehicles as one, ranged from 3.7% to 6.4%, with the best combined result being for 55 mph, 30-ft following distance, and 65k GVW.

  10. Influence of malfunctions of the maintenance activities on the urban buses fuel consumption

    NASA Astrophysics Data System (ADS)

    George, Crişan; Nicolae, Filip

    2014-06-01

    Optimization of activities with the aim to provide quality service in conditions of high profitability, is one of the main objectives chased by managers in transportation companies. As a consequence, directing the attention towards monitoring of maintenance activities of vehicles fleet, can achieve desired results. Two of the most important issues related to the maintenance activity, is the increase of reliability and reduction of fuel consumption of the vehicles fleet. Aforementioned actions represents a way forward for raising the quality and profitability of services offered. In this paper, the main ways of monitoring the fuel consumption, in order to reduce it and increase the reliability of transportation vehicles fleet, are presented. For the evaluation of the maintenance system and the degree of influence of malfunctions recorded on the fuel consumption, using the Pareto -ABC method, following case study on a fleet of buses for urban public transport has been conducted. Results obtained highlights the deficiencies of the maintenance process carried out and constitutes a solid base for the reorganization of the maintenance activity, involving preventive maintenance activities, in order to contribute decisively to the results targeted by the management of transport companies.

  11. Oxygen reduction in fuel cell electrolytes

    SciTech Connect

    Striebel, K.A.

    1987-01-01

    Voltage losses in the O{sub 2} cathode represent the major inefficiency in aqueous fuel cells for transportation or stationary applications. Experimental and theoretical studies of oxygen reduction (OR) in novel acid and alkaline electrolytes on smooth and supported Pt have been carried out. Similar kinetically limited rates for OR were measured in the super-acid electrolytes trifluoromethane sulfonic acid (TFMSA) and tetrafluoroethane-1,2-disulfonic acid (TFEDSA), with the rotating disk electrode (RDE) technique at 23 C and pH = 1. The mechanism for OR on Pt in alkaline electrolytes is complicated by the concurrent oxidation and reduction of Pt. Rotating ring-disk electrode (RRDE) studies carried out with anodic and cathodic potential sweeps in 0.1 to 6.9 M KOH and 0.1 to 4.0 M K{sub 2}CO{sub 3} revealed similar currents when corrected for O{sub 2} solubility differences. Porous gas diffusion electrodes (GDE) with supported Pt catalyst were studied in a special cell with low uncompensated solution resistance. Cyclic voltammograms yielded measurements of the wetted areas of carbon and Pt and the local electrolyte composition. Models for the steady-state operation of porous GDE's were developed. These models account for the diffusion and reaction of O{sub 2} and ionic transport in KOH and K{sub 2}CO{sub 3}. The results suggest that modifications of the GDE structure will be necessary to obtain good performance with aqueous carbonate electrolytes.

  12. Fuel consumption for interplanetary missions of solar sailing

    NASA Astrophysics Data System (ADS)

    Gong, ShengPing; Li, JunFeng

    2014-03-01

    The orbits of solar sails can be changed by adjusting the sail's attitude through external control torques. The resulting momentum will be changed, either provided by a typical attitude control subsystem or by a propellantless device. This paper investigates the extra momentum input and fuel consumption for a typical attitude control subsystem. The minimum-time transfer trajectories are designed for two rendezvous missions using both indirect and direct methods, generating continuous and discrete attitude histories, respectively. The results show that the momentum variation is almost wholly due to the solar radiation pressure. The feasibility of using tip-mounted microthrusters for attitude control is evaluated. The results show that less than 0.1 kg of propellant are required for an interplanetary transfer mission when pulsed plasma thrusters with a specific impulse of 700 s and a thrust of 150 mN are mounted at the tip of a 20 m square solar sail. The fuel consumptions of two transfer missions indicate that a tip-mounted pulsed plasma thruster is a viable technique for the attitude control of a solar sail.

  13. Biomass burning fuel consumption rates: a field measurement database

    NASA Astrophysics Data System (ADS)

    van Leeuwen, T. T.; van der Werf, G. R.; Hoffmann, A. A.; Detmers, R. G.; Rücker, G.; French, N. H. F.; Archibald, S.; Carvalho, J. A., Jr.; Cook, G. D.; de Groot, W. J.; Hély, C.; Kasischke, E. S.; Kloster, S.; McCarty, J. L.; Pettinari, M. L.; Savadogo, P.; Alvarado, E. C.; Boschetti, L.; Manuri, S.; Meyer, C. P.; Siegert, F.; Trollope, L. A.; Trollope, W. S. W.

    2014-06-01

    Landscape fires show large variability in the amount of biomass or fuel consumed per unit area burned. These fuel consumption (FC) rates depend on the biomass available to burn and the fraction of the biomass that is actually combusted, and can be combined with estimates of area burned to assess emissions. While burned area can be detected from space and estimates are becoming more reliable due to improved algorithms and sensors, FC rates are either modeled or taken selectively from the literature. We compiled the peer-reviewed literature on FC rates for various biomes and fuel categories to better understand FC rates and variability, and to provide a~database that can be used to constrain biogeochemical models with fire modules. We compiled in total 76 studies covering 10 biomes including savanna (15 studies, average FC of 4.6 t DM (dry matter) ha-1), tropical forest (n = 19, FC = 126), temperate forest (n = 11, FC = 93), boreal forest (n = 16, FC = 39), pasture (n = 6, FC = 28), crop residue (n = 4, FC = 6.5), chaparral (n = 2, FC = 32), tropical peatland (n = 4, FC = 314), boreal peatland (n = 2, FC = 42), and tundra (n = 1, FC = 40). Within biomes the regional variability in the number of measurements was sometimes large, with e.g. only 3 measurement locations in boreal Russia and 35 sites in North America. Substantial regional differences were found within the defined biomes: for example FC rates of temperate pine forests in the USA were 38% higher than Australian forests dominated by eucalypt trees. Besides showing the differences between biomes, FC estimates were also grouped into different fuel classes. Our results highlight the large variability in FC rates, not only between biomes but also within biomes and fuel classes. This implies that care should be taken with using averaged values, and our comparison with FC rates from GFED3 indicates that also modeling studies have difficulty in representing the dynamics governing FC.

  14. Reduction in Energy Consumption & Variability in Steel Foundry Operations

    SciTech Connect

    Frank Peters

    2005-05-04

    This project worked to improve the efficiency of the steel casting industry by reducing the variability that occurs because of process and product variation. The project focused on the post shakeout operations since roughly half of the production costs are in this area. These improvements will reduce the amount of variability, making it easier to manage the operation and improve the competitiveness. The reduction in variability will also reduce the need for many rework operations, which will result in a direct reduction of energy usage, particularly by the reduction of repeated heat treatment operations. Further energy savings will be realized from the reduction of scrap and reduced handling. Field studies were conducted at ten steel foundries that represented the U.S. steel casting industry, for a total of over 100 weeks of production observation. These studies quantified the amount of variability, and looked toward determining the source. A focus of the data collected was the grinding operations since this is a major effort in the cleaning room, and it represents the overall casting quality. The grinding was divided into two categories, expected and unexpected. Expected grinding is that in which the location of the effort is known prior to making the casting, such as smoothing parting lines, gates, and riser contacts. Unexpected grinding, which was approximately 80% of the effort, was done to improve the surfaces at weld repair locations, to rectify burnt on sand, and other surface anomalies at random locations. Unexpected grinding represents about 80% of the grinding effort. By quantifying this effort, the project raised awareness within the industry and the industry is continuing to make improvements. The field studies showed that the amount of variation of grinding operations (normalized because of the diverse set of parts studied) was very consistent across the industry. The field studies identified several specific sources that individually contributed to

  15. Biomass burning fuel consumption dynamics in the tropics and subtropics assessed from satellite

    NASA Astrophysics Data System (ADS)

    Andela, Niels; van der Werf, Guido R.; Kaiser, Johannes W.; van Leeuwen, Thijs T.; Wooster, Martin J.; Lehmann, Caroline E. R.

    2016-06-01

    Landscape fires occur on a large scale in (sub)tropical savannas and grasslands, affecting ecosystem dynamics, regional air quality and concentrations of atmospheric trace gasses. Fuel consumption per unit of area burned is an important but poorly constrained parameter in fire emission modelling. We combined satellite-derived burned area with fire radiative power (FRP) data to derive fuel consumption estimates for land cover types with low tree cover in South America, Sub-Saharan Africa, and Australia. We developed a new approach to estimate fuel consumption, based on FRP data from the polar-orbiting Moderate Resolution Imaging Spectroradiometer (MODIS) and the geostationary Spinning Enhanced Visible and Infrared Imager (SEVIRI) in combination with MODIS burned-area estimates. The fuel consumption estimates based on the geostationary and polar-orbiting instruments showed good agreement in terms of spatial patterns. We used field measurements of fuel consumption to constrain our results, but the large variation in fuel consumption in both space and time complicated this comparison and absolute fuel consumption estimates remained more uncertain. Spatial patterns in fuel consumption could be partly explained by vegetation productivity and fire return periods. In South America, most fires occurred in savannas with relatively long fire return periods, resulting in comparatively high fuel consumption as opposed to the more frequently burning savannas in Sub-Saharan Africa. Strikingly, we found the infrequently burning interior of Australia to have higher fuel consumption than the more productive but frequently burning savannas in northern Australia. Vegetation type also played an important role in explaining the distribution of fuel consumption, by affecting both fuel build-up rates and fire return periods. Hummock grasslands, which were responsible for a large share of Australian biomass burning, showed larger fuel build-up rates than equally productive grasslands in

  16. Peak-Seeking Optimization of Trim for Reduced Fuel Consumption: Architecture and Performance Predictions

    NASA Technical Reports Server (NTRS)

    Schaefer, Jacob; Brown, Nelson A.

    2013-01-01

    A peak-seeking control approach for real-time trim configuration optimization for reduced fuel consumption has been developed by researchers at the National Aeronautics and Space Administration (NASA) Dryden Flight Research Center to address the goals of the NASA Environmentally Responsible Aviation project to reduce fuel burn and emissions. The peak-seeking control approach is based on a steepest-descent algorithm using a time-varying Kalman filter to estimate the gradient of a performance function of fuel flow versus control surface positions. In real-time operation, deflections of symmetric ailerons, trailing-edge flaps, and leading-edge flaps of an F/A-18 airplane (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) are controlled for optimization of fuel flow. This paper presents the design and integration of this peak-seeking controller on a modified NASA F/A-18 airplane with research flight control computers. A research flight was performed to collect data to build a realistic model of the performance function and characterize measurement noise. This model was then implemented into a nonlinear six-degree-of-freedom F/A-18 simulation along with the peak-seeking control algorithm. With the goal of eventual flight tests, the algorithm was first evaluated in the improved simulation environment. Results from the simulation predict good convergence on minimum fuel flow with a 2.5-percent reduction in fuel flow relative to the baseline trim of the aircraft.

  17. Peak-Seeking Optimization of Trim for Reduced Fuel Consumption: Architecture and Performance Predictions

    NASA Technical Reports Server (NTRS)

    Schaefer, Jacob; Brown, Nelson

    2013-01-01

    A peak-seeking control approach for real-time trim configuration optimization for reduced fuel consumption has been developed by researchers at the National Aeronautics and Space Administration (NASA) Dryden Flight Research Center to address the goals of the NASA Environmentally Responsible Aviation project to reduce fuel burn and emissions. The peak-seeking control approach is based on a steepest-descent algorithm using a time-varying Kalman filter to estimate the gradient of a performance function of fuel flow versus control surface positions. In real-time operation, deflections of symmetric ailerons, trailing-edge flaps, and leading-edge flaps of an FA-18 airplane (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) are controlled for optimization of fuel flow. This presentation presents the design and integration of this peak-seeking controller on a modified NASA FA-18 airplane with research flight control computers. A research flight was performed to collect data to build a realistic model of the performance function and characterize measurement noise. This model was then implemented into a nonlinear six-degree-of-freedom FA-18 simulation along with the peak-seeking control algorithm. With the goal of eventual flight tests, the algorithm was first evaluated in the improved simulation environment. Results from the simulation predict good convergence on minimum fuel flow with a 2.5-percent reduction in fuel flow relative to the baseline trim of the aircraft.

  18. Fuel Savings and Emission Reductions from Next-Generation Mobile Air Conditioning Technology in India

    SciTech Connect

    Chaney, L.; Thundiyil, K.; Andersen, S.; Chidambaram, S.; Abbi, Y. P.

    2007-01-01

    Up to 19.4% of vehicle fuel consumption in India is devoted to air conditioning (A/C). Indian A/C fuel consumption is almost four times the fuel penalty in the United States and close to six times that in the European Union because India's temperature and humidity are higher and because road congestion forces vehicles to operate inefficiently. Car A/C efficiency in India is an issue worthy of national attention considering the rate of increase of A/C penetration into the new car market, India's hot climatic conditions and high fuel costs. Car A/C systems originally posed an ozone layer depletion concern. Now that industrialized and many developing countries have moved away from ozone-depleting substances per Montreal Protocol obligations, car A/C impact on climate has captured the attention of policy makers and corporate leaders. Car A/C systems have a climate impact from potent global warming potential gas emissions and from fuel used to power the car A/Cs. This paper focuses on car A/C fuel consumption in the context of the rapidly expanding Indian car market and how new technological improvements can result in significant fuel savings and consequently, emission reductions. A 19.4% fuel penalty is associated with A/C use in the typical Indian passenger car. Car A/C fuel use and associated tailpipe emissions are strong functions of vehicle design, vehicle use, and climate conditions. Several techniques: reducing thermal load, improving vehicle design, improving occupants thermal comfort design, improving equipment, educating consumers on impacts of driver behaviour on MAC fuel use, and others - can lead to reduced A/C fuel consumption.

  19. SEWAGE SLUDGE INCINERATOR FUEL REDUCTION, HARTFORD, CONNECTICUT

    EPA Science Inventory

    A field demonstration project was conducted at Hartford, Connecticut, which showed that the supplemental fuel usage for sewage sludge incineration could be reduced 83%. This was accomplished by using a belt press filter for dewatering which reduced fuel usage 65% and then fuel ef...

  20. A High Fuel Consumption Efficiency Management Scheme for PHEVs Using an Adaptive Genetic Algorithm

    PubMed Central

    Lee, Wah Ching; Tsang, Kim Fung; Chi, Hao Ran; Hung, Faan Hei; Wu, Chung Kit; Chui, Kwok Tai; Lau, Wing Hong; Leung, Yat Wah

    2015-01-01

    A high fuel efficiency management scheme for plug-in hybrid electric vehicles (PHEVs) has been developed. In order to achieve fuel consumption reduction, an adaptive genetic algorithm scheme has been designed to adaptively manage the energy resource usage. The objective function of the genetic algorithm is implemented by designing a fuzzy logic controller which closely monitors and resembles the driving conditions and environment of PHEVs, thus trading off between petrol versus electricity for optimal driving efficiency. Comparison between calculated results and publicized data shows that the achieved efficiency of the fuzzified genetic algorithm is better by 10% than existing schemes. The developed scheme, if fully adopted, would help reduce over 600 tons of CO2 emissions worldwide every day. PMID:25587974

  1. A high fuel consumption efficiency management scheme for PHEVs using an adaptive genetic algorithm.

    PubMed

    Lee, Wah Ching; Tsang, Kim Fung; Chi, Hao Ran; Hung, Faan Hei; Wu, Chung Kit; Chui, Kwok Tai; Lau, Wing Hong; Leung, Yat Wah

    2015-01-01

    A high fuel efficiency management scheme for plug-in hybrid electric vehicles (PHEVs) has been developed. In order to achieve fuel consumption reduction, an adaptive genetic algorithm scheme has been designed to adaptively manage the energy resource usage. The objective function of the genetic algorithm is implemented by designing a fuzzy logic controller which closely monitors and resembles the driving conditions and environment of PHEVs, thus trading off between petrol versus electricity for optimal driving efficiency. Comparison between calculated results and publicized data shows that the achieved efficiency of the fuzzified genetic algorithm is better by 10% than existing schemes. The developed scheme, if fully adopted, would help reduce over 600 tons of CO2 emissions worldwide every day. PMID:25587974

  2. Biomass burning fuel consumption rates: a field measurement database

    NASA Astrophysics Data System (ADS)

    van Leeuwen, T. T.; van der Werf, G. R.; Hoffmann, A. A.; Detmers, R. G.; Rücker, G.; French, N. H. F.; Archibald, S.; Carvalho, J. A., Jr.; Cook, G. D.; de Groot, W. J.; Hély, C.; Kasischke, E. S.; Kloster, S.; McCarty, J. L.; Pettinari, M. L.; Savadogo, P.; Alvarado, E. C.; Boschetti, L.; Manuri, S.; Meyer, C. P.; Siegert, F.; Trollope, L. A.; Trollope, W. S. W.

    2014-12-01

    Landscape fires show large variability in the amount of biomass or fuel consumed per unit area burned. Fuel consumption (FC) depends on the biomass available to burn and the fraction of the biomass that is actually combusted, and can be combined with estimates of area burned to assess emissions. While burned area can be detected from space and estimates are becoming more reliable due to improved algorithms and sensors, FC is usually modeled or taken selectively from the literature. We compiled the peer-reviewed literature on FC for various biomes and fuel categories to understand FC and its variability better, and to provide a database that can be used to constrain biogeochemical models with fire modules. We compiled in total 77 studies covering 11 biomes including savanna (15 studies, average FC of 4.6 t DM (dry matter) ha-1 with a standard deviation of 2.2), tropical forest (n = 19, FC = 126 ± 77), temperate forest (n = 12, FC = 58 ± 72), boreal forest (n = 16, FC = 35 ± 24), pasture (n = 4, FC = 28 ± 9.3), shifting cultivation (n = 2, FC = 23, with a range of 4.0-43), crop residue (n = 4, FC = 6.5 ± 9.0), chaparral (n = 3, FC = 27 ± 19), tropical peatland (n = 4, FC = 314 ± 196), boreal peatland (n = 2, FC = 42 [42-43]), and tundra (n = 1, FC = 40). Within biomes the regional variability in the number of measurements was sometimes large, with e.g. only three measurement locations in boreal Russia and 35 sites in North America. Substantial regional differences in FC were found within the defined biomes: for example, FC of temperate pine forests in the USA was 37% lower than Australian forests dominated by eucalypt trees. Besides showing the differences between biomes, FC estimates were also grouped into different fuel classes. Our results highlight the large variability in FC, not only between biomes but also within biomes and fuel classes. This implies that substantial uncertainties are associated with using biome-averaged values to represent FC for whole

  3. Fuel Consumption of a Carburetor Engine at Various Speeds and Torques

    NASA Technical Reports Server (NTRS)

    Schey, Oscar W; Clark, J Denny

    1938-01-01

    An investigation was conducted to obtain fuel-consumption curves for a single-cylinder engine with a Wright 1820-G and Pratt & Whitney 1340-H cylinder at varying speeds, manifold pressures, and air-fuel ratios. The 1340- H cylinder was tested at speeds from 1,200 to 2,400 r.p.m. and at manifold pressures from 21 to 38 inches of mercury absolute. Less than extensive tests were made of the 1820-G cylinder. The results of the tests showed that the minimum brake fuel consumption was obtained when the engines were operating at high torques and at speeds from 60 to 70 percent of the rated speed. The fuel consumption increased at an increasing rate as the torque was reduced; and, at 45 percent of maximum torque, the fuel consumption was 20 percent higher than at maximum torque when the engines were operating at 70 percent of rated speed. Minimum specific fuel consumption was obtained at the same air-fuel ratio regardless of compression ratio. No improvement in fuel consumption was obtained when mixtures leaner than an air-fuel ratio of 15.5 were used. The leanest mixture ratio on which the engine with the 1340-H cylinder would operate smoothly was 18.5 and the spark advance for maximum power with this mixture ratio was 50 degrees B.T.C. A method is discussed for reducing the amount of testing necessary to obtain curves for minimum brake fuel consumption.

  4. DEVELOPMENT OF ELECTROCHEMICAL REDUCTION TECHNOLOGY FOR SPENT OXIDE FUELS

    SciTech Connect

    Hur, Jin-Mok; Seo, Chung-Seok; Kim, Ik-Soo; Hong, Sun-Seok; Kang, Dae-Seung; Park, Seong-Won

    2003-02-27

    The Advanced Spent Fuel Conditioning Process (ACP) has been under development at Korea Atomic Energy Research Institute (KAERI) since 1997. The concept is to convert spent oxide fuel into metallic form and to remove high heat-load fission products such as Cs and Sr from the spent fuel. The heat power, volume, and radioactivity of spent fuel can decrease by a factor of a quarter via this process. For the realization of ACP, a concept of electrochemical reduction of spent oxide fuel in Li2O-LiCl molten salt was proposed and several cold tests using fresh uranium oxides have been carried out. In this new electrochemical reduction process, electrolysis of Li2O and reduction of uranium oxide are taking place simultaneously at the cathode part of electrolysis cell. The conversion of uranium oxide to uranium metal can reach more than 99% ensuring the feasibility of this process.

  5. Several new catalysts for reduction of oxygen in fuel cells

    NASA Technical Reports Server (NTRS)

    Cattabriga, R. A.; Cohn, E. M.; Giner, J. D.; Makrides, A. C.; Swette, L. L.

    1970-01-01

    Test results prove nickel carbide or nitride, nickel-cobalt carbide, titanium carbide or nitride, and intermetallic compounds of the transition or noble metals to be efficient electrocatalysts for oxygen reduction in alkaline electrolytes in low temperature fuel cells.

  6. Fuel consumptions and exhaust emissions induced by cooperative adaptive cruise control strategies

    NASA Astrophysics Data System (ADS)

    Yu, Shaowei; Shi, Zhongke

    2015-04-01

    Many cooperative adaptive cruise control strategies have been presented to improve traffic efficiency as well as road traffic safety, but scholars have rarely explored the impacts of these strategies on cars' fuel consumptions and exhaust emissions. In this paper, we respectively select two-velocity difference model, multiple velocity difference model and the car-following model considering multiple preceding cars' accelerations to investigate each car's fuel consumptions, carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxides (NOX) emissions and carry out comparative analysis. The comparisons of fuel consumptions and exhaust emissions in three different cruise control strategies show that cooperative cars simulated by the car-following model considering multiple preceding cars' accelerations can run with the minimal fuel consumptions, CO, HC and NOX emissions, thus, taking the car-following model considering multiple preceding cars' accelerations as the cooperative adaptive cruise control strategy can significantly improve cars' fuel efficiency and exhaust emissions.

  7. Developing Singapore Driving Cycle for passenger cars to estimate fuel consumption and vehicular emissions

    NASA Astrophysics Data System (ADS)

    Ho, Sze-Hwee; Wong, Yiik-Diew; Chang, Victor Wei-Chung

    2014-11-01

    Singapore has pledged to attain 7-11% Business-As-Usual carbon emissions reduction by 2020. Road transport sector is a significant source of carbon emissions, estimated to be the third largest sector in Singapore. A current gap in environmental evaluation for road transport activities in Singapore is the lack of a representative driving cycle for passenger cars (64% of the total population of 974,170 vehicles). This Singapore Driving Cycle (SDC) is hence developed for Singapore roads and traffic conditions. A chase-car (instrumented vehicle) was used to collect on-road data along 12 designed routes, and circulation driving on highly utilized arterial roads (including those in Central Business District (CBD) and both inner and outer ring roads fringing the CBD area). The SDC was thus hence constructed, with consideration of road type proportions, time periods and desired distance, duration and peak-lull proportion. In essence, the SDC is a 2400-s speed-time profile to represent the driving pattern for passenger car in Singapore. Microscopic estimation model (CMEM) shows that, as compared to SDC, the New European Driving Cycle (NEDC) underestimates most of the vehicular emissions (fuel, CO2, HC and NOx by 5%, 5%, 22% and 47%, respectively) and overestimates CO by 8%. The SDC is thus more suitable than the NEDC that is currently in use in Singapore; the SDC can be used to generate more accurate fuel consumption and emissions ratings for various uses (for example, inventory of vehicular emissions and fuel economy labelling).

  8. Peak Seeking Control for Reduced Fuel Consumption with Preliminary Flight Test Results

    NASA Technical Reports Server (NTRS)

    Brown, Nelson

    2012-01-01

    The Environmentally Responsible Aviation project seeks to accomplish the simultaneous reduction of fuel burn, noise, and emissions. A project at NASA Dryden Flight Research Center is contributing to ERAs goals by exploring the practical application of real-time trim configuration optimization for enhanced performance and reduced fuel consumption. This peak-seeking control approach is based on Newton-Raphson algorithm using a time-varying Kalman filter to estimate the gradient of the performance function. In real-time operation, deflection of symmetric ailerons, trailing-edge flaps, and leading-edge flaps of a modified F-18 are directly optimized, and the horizontal stabilators and angle of attack are indirectly optimized. Preliminary results from three research flights are presented herein. The optimization system found a trim configuration that required approximately 3.5% less fuel flow than the baseline trim at the given flight condition. The algorithm consistently rediscovered the solution from several initial conditions. These preliminary results show the algorithm has good performance and is expected to show similar results at other flight conditions and aircraft configurations.

  9. Optimization to reduce fuel consumption in charge depleting mode

    SciTech Connect

    Roos, Bryan Nathaniel; Martini, Ryan D.

    2014-08-26

    A powertrain includes an internal combustion engine, a motor utilizing electrical energy from an energy storage device, and a plug-in connection. A Method for controlling the powertrain includes monitoring a fuel cut mode, ceasing a fuel flow to the engine based upon the fuel cut mode, and through a period of operation including acceleration of the powertrain, providing an entirety of propelling torque to the powertrain with the electrical energy from the energy storage device based upon the fuel cut mode.

  10. A modal approach to vehicular emissions and fuel consumption model development.

    PubMed

    Hung, Wing-Tat; Tong, Hing-Yan; Cheung, Chun-Shun

    2005-10-01

    This study reports on the analysis of emissions and fuel consumption from motor vehicles using a modal approach. The four standard driving modes are idling, accelerating, cruising, and decelerating. On-road data were collected using instrumented test vehicles traveling many times through the urban areas of Hong Kong. A model was developed for estimating vehicular fuel consumption and emissions as a function of instantaneous speed and driving mode. Piecewise interpolation functions were proposed for each nonidling driving mode. Idling emission and fuel consumption rates were estimated as negative exponential functions of idling time. Preliminary modeling results showed good agreements for the test vehicles and indicated that the on-road measurements are feasible for the development of modal emission and fuel consumption models. PMID:16295267

  11. Full-scale altitude engine test of a turbofan exhaust-gas-forced mixer to reduce thrust specific fuel consumption

    NASA Technical Reports Server (NTRS)

    Cullom, R. R.; Johnson, R. L.

    1977-01-01

    The specific fuel consumption of a low-bypass-ratio, confluent-flow, turbofan engine was measured with and without a mixer installed. Tests were conducted for flight Mach numbers from 0.3 to 1.4 and altitudes from 10,670 to 14,630 meters (35,000 to 48,000 ft) for core-stream-to-fan-stream temperature ratios of 2.0 and 2.5 and mixing-length-to-diameter ratios of 0.95 and 1.74. For these test conditions, the reduction in specific fuel consumption varied from 2.5 percent to 4.0 percent. Pressure loss measurements as well as temperature and pressure surveys at the mixer inlet, the mixer exit, and the nozzle inlet were made.

  12. Black carbon emissions reductions from combustion of alternative jet fuels

    NASA Astrophysics Data System (ADS)

    Speth, Raymond L.; Rojo, Carolina; Malina, Robert; Barrett, Steven R. H.

    2015-03-01

    Recent measurement campaigns for alternative aviation fuels indicate that black carbon emissions from gas turbines are reduced significantly with the use of alternative jet fuels that are low in aromatic content. This could have significant climate and air quality-related benefits that are currently not accounted for in environmental assessments of alternative jet fuels. There is currently no predictive way of estimating aircraft black carbon emissions given an alternative jet fuel. We examine the results from available measurement campaigns and propose a first analytical approximation (termed 'ASAF') of the black carbon emissions reduction associated with the use of paraffinic alternative jet fuels. We establish a relationship between the reduction in black carbon emissions relative to conventional jet fuel for a given aircraft, thrust setting relative to maximum rated thrust, and the aromatic volume fraction of the (blended) alternative fuel. The proposed relationship is constrained to produce physically meaningful results, makes use of only one free parameter and is found to explain a majority of the variability in measurements across the engines and fuels that have been tested.

  13. Impact of methanol-gasoline fuel blend on the fuel consumption and exhaust emission of a SI engine

    NASA Astrophysics Data System (ADS)

    Rifal, Mohamad; Sinaga, Nazaruddin

    2016-04-01

    In this study, the effect of methanol-gasoline fuel blend (M15, M30 and M50) on the fuel consumption and exhaust emission of a spark ignition engine (SI) were investigated. In the experiment, an engine four-cylinder, four stroke injection system (engine of Toyota Kijang Innova 1TR-FE) was used. Test were did to know the relation of fuel consumption and exhaust emission (CO, CO2, HC) were analyzed under the idle throttle operating condition and variable engine speed ranging from 1000 to 4000 rpm. The experimental result showed that the fuel consumption decrease with the use of methanol. It was also shown that the CO and HC emission were reduced with the increase methanol content while CO2 were increased.

  14. Reduction in Power Consumption for Full-Color Active Matrix Organic Light-Emitting Devices

    NASA Astrophysics Data System (ADS)

    Kanno, Hiroshi; Hamada, Yuji; Nishimura, Kazuki; Okumoto, Kenji; Saito, Nobuo; Mameno, Kazunobu; Shibata, Kenichi

    2006-09-01

    The active matrix organic light-emitting diode (AMOLED) is expected to serve as next generation flat panels display with the outstanding features of wide viewing angle, vivid images, and quick response. For practical use of full-color AMOLEDs in mobile devices, it is essential to reduce the power consumption, which is generally higher than that of liquid crystal displays (LCDs). For this aim, a red, green, blue, and white (RGBW) pixel format combined with an RGB color filter array (RGBW format) with a common white emission layer (EML) has been developed. We find that the RGBW format can successfully reduce the power consumption of a full-color AMOLED by nearly half that of a conventionally filtered RGB pixel format. This improved power consumption is almost equal to the power consumption of a same-sized LCD. The RGBW format is a promising technique for the further reduction of the power consumption of a full-color AMOLED.

  15. Impact of Solar Control PVB Glass on Vehicle Interior Temperatures, Air-Conditioning Capacity, Fuel Consumption, and Vehicle Range

    SciTech Connect

    Rugh, J.; Chaney, L.; Venson, T.; Ramroth, L.; Rose, M.

    2013-04-01

    The objective of the study was to assess the impact of Saflex1 S-series Solar Control PVB (polyvinyl butyral) configurations on conventional vehicle fuel economy and electric vehicle (EV) range. The approach included outdoor vehicle thermal soak testing, RadTherm cool-down analysis, and vehicle simulations. Thermal soak tests were conducted at the National Renewable Energy Laboratory's Vehicle Testing and Integration Facility in Golden, Colorado. The test results quantified interior temperature reductions and were used to generate initial conditions for the RadTherm cool-down analysis. The RadTherm model determined the potential reduction in air-conditioning (A/C) capacity, which was used to calculate the A/C load for the vehicle simulations. The vehicle simulation tool identified the potential reduction in fuel consumption or improvement in EV range between a baseline and modified configurations for the city and highway drive cycles. The thermal analysis determined a potential 4.0% reduction in A/C power for the Saflex Solar PVB solar control configuration. The reduction in A/C power improved the vehicle range of EVs and fuel economy of conventional vehicles and plug-in hybrid electric vehicles.

  16. Vegetation structure and fire weather influence variation in burn severity and fuel consumption during peatland wildfires

    NASA Astrophysics Data System (ADS)

    Davies, G. M.; Domènech, R.; Gray, A.; Johnson, P. C. D.

    2015-09-01

    Temperate peatland wildfires are of significant environmental concern but information on their environmental effects is lacking. We assessed variation in burn severity and fuel consumption within and between wildfires that burnt British moorlands in 2011 and 2012. We adapted the Composite Burn Index (pCBI) to provide semi-quantitative estimates of burn severity. Pre- and post-fire surface (shrubs and graminoids) and ground (litter, moss, duff) fuel loads associated with large wildfires were assessed using destructive sampling and analysed using a Generalised Linear Mixed Model (GLMM). Consumption during wildfires was compared with published estimates of consumption during prescribed burns. Burn severity and fuel consumption were related to fire weather, assessed using the Canadian Fire Weather Index System (FWI System), and pre-fire fuel structure. pCBI varied 1.6 fold between, and up to 1.7 fold within, wildfires. pCBI was higher where moisture codes of the FWI System indicated drier fuels. Spatial variation in pre- and post-fire fuel load accounted for a substantial proportion of the variance in fuel loads. Average surface fuel consumption was a linear function of pre-fire fuel load. Average ground fuel combustion completeness could be predicted by the Buildup Index. Carbon release ranged between 0.36 and 1.00 kg C m-2. The flammability of ground fuel layers may explain the higher C release-rates seen for wildfires in comparison to prescribed burns. Drier moorland community types appear to be at greater risk of severe burns than blanket-bog communities.

  17. Treatment of oxide spent fuel using the lithium reduction process

    SciTech Connect

    Karell, E.J.; Pierce, R.D.; Mulcahey, T.P.

    1996-05-01

    The wide variety in the composition of DOE spent nuclear fuel complicates its long-term disposition because of the potential requirement to individually qualify each type of fuel for repository disposal. Argonne National Laboratory (ANL) has developed the electrometallurgical treatment technique to convert all of these spent fuel types into a single set of disposal forms, simplifying the qualification process. While metallic fuels can be directly processed using the electrometallurgical treatment technique, oxide fuels must first be reduced to the metallic form. The lithium reduction process accomplishes this pretreatment. In the lithium process the oxide components of the fuel are reduced using lithium at 650 C in the presence of molten LiCl, yielding the corresponding metals and Li{sub 2}O. The reduced metal components are then separated from the LiCl salt phase and become the feed material for electrometallurgical treatment. A demonstration test of the lithium reduction process was successfully conducted using a 10-kg batch of simulated oxide spent fuel and engineering-scale equipment specifically constructed for that purpose. This paper describes the lithium process, the equipment used in the demonstration test, and the results of the demonstration test.

  18. Cost and fuel consumption per nautical mile for two engine jet transports using OPTIM and TRAGEN

    NASA Technical Reports Server (NTRS)

    Wiggs, J. F.

    1982-01-01

    The cost and fuel consumption per nautical mile for two engine jet transports are computed using OPTIM and TRAGEN. The savings in fuel and direct operating costs per nautical mile for each of the different types of optimal trajectories over a standard profile are shown.

  19. Analysis of the cumulative exergy consumption of an integrated oxy-fuel combustion power plant

    NASA Astrophysics Data System (ADS)

    Ziębik, Andrzej; Gładysz, Paweł

    2013-09-01

    In order to analyze the cumulative exergy consumption of an integrated oxy-fuel combustion power plant the method of balance equations was applied based on the principle that the cumulative exergy consumption charging the products of this process equals the sum of cumulative exergy consumption charging the substrates. The set of balance equations of the cumulative exergy consumption bases on the `input-output method' of the direct energy consumption. In the structure of the balance we distinguished main products (e.g. electricity), by-products (e.g. nitrogen) and external supplies (fuels). In the balance model of cumulative exergy consumption it has been assumed that the cumulative exergy consumption charging the supplies from outside is a quantity known a priori resulting from the analysis of cumulative exergy consumption concerning the economy of the whole country. The byproducts are charged by the cumulative exergy consumption resulting from the principle of a replaced process. The cumulative exergy consumption of the main products is the final quantity.

  20. Oxygen reduction in fuel cell electrolytes

    SciTech Connect

    Striebel, K.A.; McLarnon, F.R.; Cairns, E.J.

    1987-12-01

    Experimental and theoretical studies of oxygen reduction (OR) in novel acid and alkaline electrolytes on smooth and supported Pt have been carried out. Similar kinetically limited rates for OR were measured in the /open quotes/super-acid/close quotes/ electrolytes trifluoromethane sulfonic acid (TFMSA) and tetrafluoroethane-1,2-disulfonic acid (TFEDSA), with the rotating disk electrode (RDE) technique at 23/degree/C and pH = 1. A first-order dependence on O/sub 2/ pressure was measured. The mechanism for OR on Pt in alkaline electrolytes is complicated by the concurrent oxidation and reduction of Pt. Rotating ring-disk electrode (RRDE) studies carried out with anodic and cathodic potential sweeps in 0.1 to 6.9 M KOH and 0.1 to 4.0 M K/sub 2/CO/sub 3/ revealed similar currents when corrected for O/sub 2/ solubility differences. In dilute electrolytes, OR proceeds primarily through the 4-electron pathway to water, independent of pH. In KOH, the mechanism for Pt oxidation changes and the fraction of current yielding a peroxide product increases at 2 to 3 M. These changes were not observed in K/sub 2/CO/sub 3/. Porous gas diffusion electrodes (GDE) with supported Pt catalyst were studied in a special cell with low uncompensated solution resistance. Cyclic voltammograms yielded measurements of the wetted areas of carbon and Pt and the local electrolyte composition. GDE galvanostatic steady-state performance with 100% O/sub 2/ was measured in 2 to 11 M KOH and 2 to 5.5 M K/sub 2/CO/sub 3/. Results suggest that OR on carbon contributes to the high currents in 6.9 M KOH at high overpotentials. In K/sub 2/CO/sub 3/, lower wetted areas and slow OH/sup /minus// ion transport are responsible for the poor performance when compared with KOH. Models for the steady-state operation of porous GDE's were developed. These models account for the diffusion and reaction of O/sub 2/ and ionic transport in KOH and K/sub 2/CO/sub 3/. 120 refs., 71 figs., 11 tabs.

  1. Short-Term Energy Outlook Model Documentation: Electricity Generation and Fuel Consumption Models

    EIA Publications

    2014-01-01

    The electricity generation and fuel consumption models of the Short-Term Energy Outlook (STEO) model provide forecasts of electricity generation from various types of energy sources and forecasts of the quantities of fossil fuels consumed for power generation. The structure of the electricity industry and the behavior of power generators varies between different areas of the United States. In order to capture these differences, the STEO electricity supply and fuel consumption models are designed to provide forecasts for the four primary Census regions.

  2. Vegetation structure and fire weather influence variation in burn severity and fuel consumption during peatland wildfires

    NASA Astrophysics Data System (ADS)

    Davies, G. M.; Domènech, R.; Gray, A.; Johnson, P. C. D.

    2016-01-01

    Temperate peatland wildfires are of significant environmental concern but information on their environmental effects is lacking. We assessed variation in burn severity and fuel consumption within and between wildfires that burnt British moorlands in 2011 and 2012. We adapted the composite burn index (pCBI) to provide semi-quantitative estimates of burn severity. Pre- and post-fire surface (shrubs and graminoids) and ground (litter, moss, duff) fuel loads associated with large wildfires were assessed using destructive sampling and analysed using a generalised linear mixed model (GLMM). Consumption during wildfires was compared with published estimates of consumption during prescribed burns. Burn severity and fuel consumption were related to fire weather, assessed using the Canadian Fire Weather Index System (FWI System), and pre-fire vegetation type. pCBI varied 1.6 fold between, and up to 1.7 fold within, wildfires. pCBI was higher where moisture codes of the FWI System indicated drier fuels. Spatial variation in pre- and post-fire fuel load accounted for a substantial proportion of the variance in fuel loads. Average surface fuel consumption was a linear function of pre-fire fuel load. Average ground fuel combustion completeness could be predicted by the Buildup Index. Carbon release ranged between 0.36 and 1.00 kg C m-2. The flammability of ground fuel layers may explain the higher C release-rates seen for wildfires in comparison to prescribed burns. Drier moorland community types appear to be at greater risk of severe burns than blanket-bog communities.

  3. Evaluations of 1997 Fuel Consumption Patterns of Heavy Duty Trucks

    SciTech Connect

    Santini, Danilo

    2001-08-05

    The proposed 21st Century Truck program selected three truck classes for focused analysis. On the basis of gross vehicle weight (GVW) classification, these were Class 8 (representing heavy), Class 6 (representing medium), and Class 2b (representing light). To develop and verify these selections, an evaluation of fuel use of commercial trucks was conducted, using data from the 1997 Vehicle Inventory and Use Survey (VIUS). Truck fuel use was analyzed by registered GVW class, and by body type.

  4. Engine Operation in Flight for Minimum Fuel Consumption

    NASA Technical Reports Server (NTRS)

    Reuter, George

    1939-01-01

    Engine and airplane performance data have been gathered from various sources and analyzed to determine indications of the most economical methods of flight operation from a consideration of fuel expenditure. The analysis includes the influence of such facts as fuel-air ratio, engine speed, engine knock, altitude, cylinder cooling, spark timing, and limits of cruising brake mean effective pressure. The results indicate that the cheapest power is obtained with approximately correct mixture at low engine speed and highest permissible manifold pressure. If more power is desired, the methods of obtaining it are, in order of fuel economy: (a) increasing the engine speed and maintaining safe cylinder temperatures by cooling; (b) retarding the spark or cooling further to permit higher manifold pressure; and, (c) riching the mixture. The analysis further shows that the maximum time endurance of flight occurs at the air speed corresponding to minimum thrust horsepower required and with minimum practicable engine speed. Maximum mileage per pound of fuel is obtained at slightly higher air speed. The fuel-air ratio should be approximately the theoretically correct ratio in both cases. For an engine equipped with a geared supercharger, as in the example presented, and with knock as the limiting condition, a comparison of operation at sea level and at 6,000 feet shoes flight at altitude to be more economical on the basis of both range and endurance.

  5. Performance of Thorium-Based Mixed Oxide Fuels for the Consumption of Plutonium in Current and Advanced Reactors

    SciTech Connect

    Weaver, Kevan Dean; Herring, James Stephen

    2003-07-01

    A renewed interest in thorium-based fuels has arisen lately based on the need for proliferation resistance, longer fuel cycles, higher burnup, and improved waste form characteristics. Recent studies have been directed toward homogeneously mixed, heterogeneously mixed, and seed-and-blanket thorium-uranium oxide fuel cycles that rely on "in situ" use of the bred-in 233U. However, due to the higher initial enrichment required to achieve acceptable burnups, these fuels are encountering economic constraints. Thorium can nevertheless play a large role in the nuclear fuel cycle, particularly in the reduction of plutonium inventories. While uranium-based mixed-oxide (MOX) fuel will decrease the amount of plutonium in discharged fuel, the reduction is limited due to the breeding of more plutonium (and higher actinides) from the 238U. Here, we present calculational results and a comparison of the potential burnup of a thorium-based and uranium-based mixed-oxide fuel in a light water reactor. Although the uranium-based fuels outperformed the thorium-based fuels in achievable burnup, a depletion comparison of the initially charged plutonium (both reactor and weapons grade) showed that the thorium-based fuels outperformed the uranium-based fuels by more that a factor of 2, where >70% of the total plutonium in the thorium-based fuel is consumed during the cycle. This is significant considering that the achievable burnups of the thorium-based fuels were 1.4 to 4.6 times less than the uranium-based fuels for similar plutonium enrichments. For equal specific burnups of ~60 MWd/kg (i.e., using variable plutonium weight percentages to give the desired burnup), the thorium-based fuels still outperform the uranium-based fuels by more than a factor of 2, where the total plutonium consumption in a three-batch, 18-month cycle was 60 to 70%. This is fairly significant considering that 10 to 15% (by weight) more plutonium is needed in the thorium-based fuels as compared to the uranium

  6. Water consumption footprint and land requirements of large-scale alternative diesel and jet fuel production.

    PubMed

    Staples, Mark D; Olcay, Hakan; Malina, Robert; Trivedi, Parthsarathi; Pearlson, Matthew N; Strzepek, Kenneth; Paltsev, Sergey V; Wollersheim, Christoph; Barrett, Steven R H

    2013-01-01

    Middle distillate (MD) transportation fuels, including diesel and jet fuel, make up almost 30% of liquid fuel consumption in the United States. Alternative drop-in MD and biodiesel could potentially reduce dependence on crude oil and the greenhouse gas intensity of transportation. However, the water and land resource requirements of these novel fuel production technologies must be better understood. This analysis quantifies the lifecycle green and blue water consumption footprints of producing: MD from conventional crude oil; Fischer-Tropsch MD from natural gas and coal; fermentation and advanced fermentation MD from biomass; and hydroprocessed esters and fatty acids MD and biodiesel from oilseed crops, throughout the contiguous United States. We find that FT MD and alternative MD derived from rainfed biomass have lifecycle blue water consumption footprints of 1.6 to 20.1 Lwater/LMD, comparable to conventional MD, which ranges between 4.1 and 7.4 Lwater/LMD. Alternative MD derived from irrigated biomass has a lifecycle blue water consumption footprint potentially several orders of magnitude larger, between 2.7 and 22 600 Lwater/LMD. Alternative MD derived from biomass has a lifecycle green water consumption footprint between 1.1 and 19 200 Lwater/LMD. Results are disaggregated to characterize the relationship between geo-spatial location and lifecycle water consumption footprint. We also quantify the trade-offs between blue water consumption footprint and areal MD productivity, which ranges from 490 to 4200 LMD/ha, under assumptions of rainfed and irrigated biomass cultivation. Finally, we show that if biomass cultivation for alternative MD is irrigated, the ratio of the increase in areal MD productivity to the increase in blue water consumption footprint is a function of geo-spatial location and feedstock-to-fuel production pathway. PMID:24066845

  7. Vehicle acceleration and fuel consumption when operated on JP-8 fuel. Interim report, 1 June 1988-28 February 1989

    SciTech Connect

    Owens, E.C.; Yost, D.M.; Lestz, S.J.

    1989-02-01

    A limited test program (eight combat and tactical vehicles) was conducted to obtain a quantitative estimate of the change in combat and tactical vehicle performance and fuel consumption that would occur when converting the military fleet to MIL-T-83133 JP-8 (F-34) fuel. Data specifically desired included startability and idle quality, acceleration rates, and fuel consumption. Also, a comparative assessment of the on-vehicle smoke production capabilities of combat vehicles with the two fuels was desired. As a result of these tests, it was determined that substitution of JP-8 for DF-2 reduced the acceleration rates, and thus power, of all vehicles tested except for the M928 and M1009 vehicles, which improved or remained the same. Also, all vehicles tested, except for the M88A1 light recovery vehicles, had fuel consumption increases with JP-8 that were at or below that predicted by the heating value difference between the two fuels. No drivability or idle problems occurred with any of the test vehicles.

  8. Understanding Fire Patterns and Fuel Consumption in Russian Forests: Progress and Challenges

    NASA Astrophysics Data System (ADS)

    Conard, Susan; Stocks, Brian; Cahoon, Donald; de Groot, William; Soja, Amber; Ivanova, Galina; Kukavskaya, Elena; McRae, Douglas; Ponomarev, Evgenii; Buryak, Ludmilla; Flannigan, Mike; Swetnam, Thomas; Hao, Wei Min

    2015-04-01

    Research conducted over the past 20 years has greatly changed our understanding of the extent, patterns, and impact of wildfire in the forests of Russia. The availability of remote sensing data at various scales has been essential to improvements in burned area estimates, and has allowed us to develop a new 30-year record of burned areas in Russia. Fire scar data in selected regions has provided information on fire-climate interactions over the past several centuries. And field data from experimental fires and from wildfires has provided essential information on fire behavior, fuel consumption, and ecosystem fire effects. In this presentation we discuss the historical development of improved data on burned area, fuel characterization and fuel consumption. We will emphasize the impacts of inaccuracies in source data on burned area and fire regimes, vegetation, fuels, fuel consumption, and other factors. We present model results using the Canadian BorFire to develop annual estimates of fuel consumption and emissions for the Asian part of Russia. Potential interactions of fire with large-scale atmospheric patterns appear to be an important factor in determining occurrence and timing of large fire outbreaks, and changes in these patterns are likely to drive future changes in fire regimes. Data will be presented to illustrate these effects. The presentation will conclude with a summary of the current status of knowledge and ongoing research needs.

  9. Toward full economic valuation of forest fuels-reduction treatments.

    PubMed

    Huang, Ching-Hsun; Finkral, Alex; Sorensen, Christopher; Kolb, Thomas

    2013-11-30

    Our goal was to move toward full economic valuation of fuels-reduction treatments applied to ponderosa pine (Pinus ponderosa) forests. For each of five fuels-reduction projects in northern Arizona, we calculated the economic value of carbon storage and carbon releases over one century produced by two fuels-reduction treatments of thinning following by prescribed burning every one (Rx10) or two (Rx20) decades and for no treatment followed by intense wildfire once in the first 50 years (HF50) or once in the first 100 years (HF100). Our estimates include two uses of harvested wood, the current use as pallets, and multiproduct use as paper, pallets, and construction materials. Additionally, we included the economic value of damage and loss from wildfire. Results indicate that treatments increase carbon stock in live trees over time; however, the inclusion of carbon emissions from treatments reduces net carbon storage and thereby carbon credits and revenue. The economic valuation shows that the highest net benefit of $5029.74 ha(-1) occurs for the Rx20 treatment with the HF50 baseline and the high estimated treatment benefits of avoided losses, regional economic benefits, and community value of fire risk reduction. The lowest net benefit of -$3458.02 ha(-1) occurs for the Rx10 treatment with the HF100 baseline and the low estimated treatment benefits. We conclude that current nonmarket values such as avoided wildfire damage should be included with values of traditional wood products and emerging values of carbon storage to more appropriately estimate long-term benefits and costs of forest fuels-reduction treatments. PMID:24091157

  10. Vehicular emissions and fuel consumption estimation in passer IV. Research report

    SciTech Connect

    Chaudhary, N.A.

    1995-04-01

    Gasoline consumed by vehicles traveling within urban signalized networks constitutes a large portion of the total fuel usage in the United States. In addition, pollutants emitted by these vehicles degrade urban air quality. It is well known that the optimal coordination of traffic signals on urban signalized arterials improves traffic flow and reduces gasoline consumption and vehicular emissions. The research performed in this project incorporated fuel consumption and emissions estimation procedures into PASSER IV, a program for optimizing bandwidth-based signal timings in traffic networks. The enhanced PASSER IV software will allow Traffic Engineers to better assess the impacts of alternate signal timing plans on fuel consumption and emissions of vehicles traveling in a signalized network.

  11. 40 CFR 82.7 - Grant and phase reduction of baseline production and consumption allowances for class I...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... production and consumption allowances for class I controlled substances. 82.7 Section 82.7 Protection of... OZONE Production and Consumption Controls § 82.7 Grant and phase reduction of baseline production and consumption allowances for class I controlled substances. For each control period specified in the...

  12. 40 CFR 82.7 - Grant and phase reduction of baseline production and consumption allowances for class I...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... production and consumption allowances for class I controlled substances. 82.7 Section 82.7 Protection of... OZONE Production and Consumption Controls § 82.7 Grant and phase reduction of baseline production and consumption allowances for class I controlled substances. For each control period specified in the...

  13. 40 CFR 82.7 - Grant and phase reduction of baseline production and consumption allowances for class I...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... production and consumption allowances for class I controlled substances. 82.7 Section 82.7 Protection of... OZONE Production and Consumption Controls § 82.7 Grant and phase reduction of baseline production and consumption allowances for class I controlled substances. For each control period specified in the...

  14. 40 CFR 82.7 - Grant and phase reduction of baseline production and consumption allowances for class I...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... production and consumption allowances for class I controlled substances. 82.7 Section 82.7 Protection of... OZONE Production and Consumption Controls § 82.7 Grant and phase reduction of baseline production and consumption allowances for class I controlled substances. For each control period specified in the...

  15. 40 CFR 82.7 - Grant and phase reduction of baseline production and consumption allowances for class I...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... production and consumption allowances for class I controlled substances. 82.7 Section 82.7 Protection of... OZONE Production and Consumption Controls § 82.7 Grant and phase reduction of baseline production and consumption allowances for class I controlled substances. For each control period specified in the...

  16. Issues in International Energy Consumption Analysis: Chinese Transportation Fuel Demand

    EIA Publications

    2014-01-01

    Since the 1990s, China has experienced tremendous growth in its transportation sector. By the end of 2010, China's road infrastructure had emerged as the second-largest transportation system in the world after the United States. Passenger vehicle sales are dramatically increasing from a little more than half a million in 2000, to 3.7 million in 2005, to 13.8 million in 2010. This represents a twenty-fold increase from 2000 to 2010. The unprecedented motorization development in China led to a significant increase in oil demand, which requires China to import progressively more petroleum from other countries, with its share of petroleum imports exceeding 50% of total petroleum demand since 2009. In response to growing oil import dependency, the Chinese government is adopting a broad range of policies, including promotion of fuel-efficient vehicles, fuel conservation, increasing investments in oil resources around the world, and many others.

  17. Monthly, global emissions of carbon dioxide from fossil fuel consumption

    SciTech Connect

    Andres, Robert Joseph; Gregg, JS; Losey, London M; Marland, Gregg; Boden, Thomas A

    2011-01-01

    This paper examines available data, develops a strategy and presents a monthly, global time series of fossil-fuel carbon dioxide emissions for the years 1950 2006. This monthly time series was constructed from detailed study of monthly data from the 21 countries that account for approximately 80% of global total emissions. These data were then used in a Monte Carlo approach to proxy for all remaining countries. The proportional-proxy methodology estimates by fuel group the fraction of annual emissions emitted in each country and month. Emissions from solid, liquid and gas fuels are explicitly modelled by the proportional-proxy method. The primary conclusion from this study is the global monthly time series is statistically significantly different from a uniform distribution throughout the year. Uncertainty analysis of the data presented show that the proportional-proxy method used faithfully reproduces monthly patterns in the data and the global monthly pattern of emissions is relatively insensitive to the exact proxy assignments used. The data and results presented here should lead to a better understanding of global and regional carbon cycles, especially when the mass data are combined with the stable carbon isotope data in atmospheric transport models.

  18. Inorganic contents reduction in cellulignin catalytic fuel by HGMS

    NASA Astrophysics Data System (ADS)

    Pereira, Maria Luiza G.; Rodrigues, Durval; Conte, Rosa A.; Pinatti, Daltro G.; Shigue, Carlos Y.

    2004-08-01

    Cellulignin is a catalytic fuel obtained by acidic prehydrolysis of biomass (wood, agricultural and forest residues, and the organic matter of municipal solid waste--MOL). In order to be used as a solid fuel in gas turbines with external combustor, the ash content of the cellulignin has to be as low as possible due to the corrosion effect of the Na, K, Mg, Ca and other inorganics on the turbine blades. The main objective of the work was to apply the HGMS to the cellulignin and observe the efficiency of the separation in terms of the reduction of the inorganic constituent concentrations. The separation efficiency was measured by the analysis of the cellulignin samples before and after the magnetic separation. The elements Al, Ca, Fe, K, Mg, Mn, Na, P, S, Si and Zn were determined by ICP-OES. The results showed a concentration reduction for all the elements after the HGMS, allowing this technology to be applied to the cellulignin.

  19. Estimate of Fuel Consumption and GHG Emission Impact from an Automated Mobility District

    SciTech Connect

    Chen, Yuche; Young, Stanley; Qi, Xuewei; Gonder, Jeffrey

    2015-10-19

    This study estimates the range of fuel and emissions impact of an automated-vehicle (AV) based transit system that services campus-based developments, termed an automated mobility district (AMD). The study develops a framework to quantify the fuel consumption and greenhouse gas (GHG) emission impacts of a transit system comprised of AVs, taking into consideration average vehicle fleet composition, fuel consumption/GHG emission of vehicles within specific speed bins, and the average occupancy of passenger vehicles and transit vehicles. The framework is exercised using a previous mobility analysis of a personal rapid transit (PRT) system, a system which shares many attributes with envisioned AV-based transit systems. Total fuel consumption and GHG emissions with and without an AMD are estimated, providing a range of potential system impacts on sustainability. The results of a previous case study based of a proposed implementation of PRT on the Kansas State University (KSU) campus in Manhattan, Kansas, serves as the basis to estimate personal miles traveled supplanted by an AMD at varying levels of service. The results show that an AMD has the potential to reduce total system fuel consumption and GHG emissions, but the amount is largely dependent on operating and ridership assumptions. The study points to the need to better understand ride-sharing scenarios and calls for future research on sustainability benefits of an AMD system at both vehicle and system levels.

  20. Estimate of Fuel Consumption and GHG Emission Impact on an Automated Mobility District: Preprint

    SciTech Connect

    Chen, Yuche; Young, Stanley; Gonder, Jeff; Qi, Xuewei

    2015-12-11

    This study estimates the range of fuel and emissions impact of an automated-vehicle (AV) based transit system that services campus-based developments, termed an automated mobility district (AMD). The study develops a framework to quantify the fuel consumption and greenhouse gas (GHG) emission impacts of a transit system comprised of AVs, taking into consideration average vehicle fleet composition, fuel consumption/GHG emission of vehicles within specific speed bins, and the average occupancy of passenger vehicles and transit vehicles. The framework is exercised using a previous mobility analysis of a personal rapid transit (PRT) system, a system which shares many attributes with envisioned AV-based transit systems. Total fuel consumption and GHG emissions with and without an AMD are estimated, providing a range of potential system impacts on sustainability. The results of a previous case study based of a proposed implementation of PRT on the Kansas State University (KSU) campus in Manhattan, Kansas, serves as the basis to estimate personal miles traveled supplanted by an AMD at varying levels of service. The results show that an AMD has the potential to reduce total system fuel consumption and GHG emissions, but the amount is largely dependent on operating and ridership assumptions. The study points to the need to better understand ride-sharing scenarios and calls for future research on sustainability benefits of an AMD system at both vehicle and system levels.

  1. Energy consumption in the manufacture of reformulated fuels

    SciTech Connect

    Brown, R.

    1996-03-01

    California`s RFG program, now underway, places new processing demands on the state`s refiners,particularly in sulfur and aromatics reduction in gasoline, diesel and benzene; olefins; vapor pressure and distillation T{sub 50}/T{sub 90} control in gasoline. The study provides a unique look at the energy-use impact of the new rules and gives detailed insight into the process decisions refiners must make.

  2. Modeling transit bus fuel consumption on the basis of cycle properties.

    PubMed

    Delgado, Oscar F; Clark, Nigel N; Thompson, Gregory J

    2011-04-01

    A method exists to predict heavy-duty vehicle fuel economy and emissions over an "unseen" cycle or during unseen on-road activity on the basis of fuel consumption and emissions data from measured chassis dynamometer test cycles and properties (statistical parameters) of those cycles. No regression is required for the method, which relies solely on the linear association of vehicle performance with cycle properties. This method has been advanced and examined using previously published heavy-duty truck data gathered using the West Virginia University heavy-duty chassis dynamometer with the trucks exercised over limited test cycles. In this study, data were available from a Washington Metropolitan Area Transit Authority emission testing program conducted in 2006. Chassis dynamometer data from two conventional diesel buses, two compressed natural gas buses, and one hybrid diesel bus were evaluated using an expanded driving cycle set of 16 or 17 different driving cycles. Cycle properties and vehicle fuel consumption measurements from three baseline cycles were selected to generate a linear model and then to predict unseen fuel consumption over the remaining 13 or 14 cycles. Average velocity, average positive acceleration, and number of stops per distance were found to be the desired cycle properties for use in the model. The methodology allowed for the prediction of fuel consumption with an average error of 8.5% from vehicles operating on a diverse set of chassis dynamometer cycles on the basis of relatively few experimental measurements. It was found that the data used for prediction should be acquired from a set that must include an idle cycle along with a relatively slow transient cycle and a relatively high speed cycle. The method was also applied to oxides of nitrogen prediction and was found to have less predictive capability than for fuel consumption with an average error of 20.4%. PMID:21516939

  3. 14 CFR Appendix M to Part 25 - Fuel Tank System Flammability Reduction Means

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Fuel Tank System Flammability Reduction... 25—Fuel Tank System Flammability Reduction Means M25.1Fuel tank flammability exposure requirements... the fuel tanks with FRMs (including any tanks that communicate with a tank via a vent system), and...

  4. 14 CFR Appendix M to Part 25 - Fuel Tank System Flammability Reduction Means

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Fuel Tank System Flammability Reduction... 25—Fuel Tank System Flammability Reduction Means M25.1Fuel tank flammability exposure requirements... the fuel tanks with FRMs (including any tanks that communicate with a tank via a vent system), and...

  5. 14 CFR Appendix M to Part 25 - Fuel Tank System Flammability Reduction Means

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Fuel Tank System Flammability Reduction... 25—Fuel Tank System Flammability Reduction Means M25.1Fuel tank flammability exposure requirements... the fuel tanks with FRMs (including any tanks that communicate with a tank via a vent system), and...

  6. Research on Fuel Consumption of Hybrid Bulldozer under Typical Duty Cycle

    NASA Astrophysics Data System (ADS)

    Song, Qiang; Wang, Wen-Jun; Jia, Chao; Yao, You-Liang; Wang, Sheng-Bo

    The hybrid drive bulldozer adopts a dual-motor independent drive system with engine-generator assembly as its power source. The mathematical model of the whole system is constructed on the software platform of MATLAB/Simulink. And then according to the velocity data gained from a real test experiment, a typical duty cycle is build up. Finally the fuel consumption of the bulldozer is calculated under this duty-cycle. Simulation results show that, compared with the traditional mechanical one, the hybrid electric drive system can save fuel up to 16% and therefore indicates great potential for lifting up fuel economy.

  7. Reactive thrust cruise for a geosynchronous satellite with minimum fuel consumption

    NASA Astrophysics Data System (ADS)

    Sidi, Marcel

    1993-02-01

    A simple control concept utilizing product of inertia is used to provide active nutation control of a reactive thrust control system of a geosynchronous momentum-based satellite. The reactive thrust control system itself is immune to sensor noise and thus prevents unnecessary thrust firings. Any nutation excitation is damped in a small number of nutational periods, with no fuel consumption.

  8. 49 CFR 1243.3 - Report of fuel cost, consumption, and surcharge revenue.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... days after the end of the quarter reported. Appendix to Section 49 CFR 1243.3 OMB Control No. 2140-0014... collection is required by law. Under 5 CFR 1320.5(b), persons are not required to respond to this collection... 49 Transportation 9 2011-10-01 2011-10-01 false Report of fuel cost, consumption, and...

  9. 14 CFR 291.44 - BTS Schedule P-12(a), Fuel Consumption by Type of Service and Entity.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false BTS Schedule P-12(a), Fuel Consumption by... TRANSPORTATION Reporting Rules § 291.44 BTS Schedule P-12(a), Fuel Consumption by Type of Service and Entity. (a) For the purposes of BTS schedule P-12(a), type of service shall be either scheduled service...

  10. 14 CFR 291.44 - BTS Schedule P-12(a), Fuel Consumption by Type of Service and Entity.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false BTS Schedule P-12(a), Fuel Consumption by... TRANSPORTATION Reporting Rules § 291.44 BTS Schedule P-12(a), Fuel Consumption by Type of Service and Entity. (a) For the purposes of BTS schedule P-12(a), type of service shall be either scheduled service...

  11. 14 CFR 291.44 - BTS Schedule P-12(a), Fuel Consumption by Type of Service and Entity.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false BTS Schedule P-12(a), Fuel Consumption by... TRANSPORTATION Reporting Rules § 291.44 BTS Schedule P-12(a), Fuel Consumption by Type of Service and Entity. (a) For the purposes of BTS schedule P-12(a), type of service shall be either scheduled service...

  12. 14 CFR 291.44 - BTS Schedule P-12(a), Fuel Consumption by Type of Service and Entity.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false BTS Schedule P-12(a), Fuel Consumption by... TRANSPORTATION Reporting Rules § 291.44 BTS Schedule P-12(a), Fuel Consumption by Type of Service and Entity. (a) For the purposes of BTS schedule P-12(a), type of service shall be either scheduled service...

  13. 14 CFR 291.44 - BTS Schedule P-12(a), Fuel Consumption by Type of Service and Entity.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false BTS Schedule P-12(a), Fuel Consumption by... TRANSPORTATION Reporting Rules § 291.44 BTS Schedule P-12(a), Fuel Consumption by Type of Service and Entity. (a) For the purposes of BTS schedule P-12(a), type of service shall be either scheduled service...

  14. Using the Relationship between Vehicle Fuel Consumption and CO[subscript 2] Emissions to Illustrate Chemical Principles

    ERIC Educational Resources Information Center

    Oliver-Hoyo, Maria T.; Pinto, Gabriel

    2008-01-01

    This instructional resource utilizes consumer product information by which students compare theoretical stoichiometric calculations to CO[subscript 2] car emissions and fuel consumption data. Representing graphically the emission of CO[subscript 2] versus consumption of fuel provides a tangible way of connecting concepts studied in chemistry…

  15. How hybrid-electric vehicles are different from conventional vehicles: the effect of weight and power on fuel consumption

    NASA Astrophysics Data System (ADS)

    Reynolds, C.; Kandlikar, M.

    2007-01-01

    An increasingly diverse set of hybrid-electric vehicles (HEVs) is now available in North America. The recent generation of HEVs have higher fuel consumption, are heavier, and are significantly more powerful than the first generation of HEVs. We compare HEVs for sale in the United States in 2007 to equivalent conventional vehicles and determine how vehicle weight and system power affects fuel consumption within each vehicle set. We find that heavier and more powerful hybrid-electric vehicles are eroding the fuel consumption benefit of this technology. Nonetheless, the weight penalty for fuel consumption in HEVs is significantly lower than in equivalent conventional internal combustion engine vehicles (ICEVs). A 100 kg change in vehicle weight increases fuel consumption by 0.7 l/100 km in ICEVs compared with 0.4 l/100 km in HEVs. When the HEVs are compared with their ICEV counterparts in an equivalence model that differentiates between cars and sports-utility vehicles, the average fuel consumption benefit was 2.7 l/100 km. This analysis further reveals that a HEV which is 100 kg heavier than an identical ICEV would have a fuel consumption penalty of 0.15 l/100 km. Likewise, an increase in the HEV's power by 10 kW results in a fuel consumption penalty of 0.27 l/100 km.

  16. Development of a Life Cycle Inventory of Water Consumption Associated with the Production of Transportation Fuels

    SciTech Connect

    Lampert, David J.; Cai, Hao; Wang, Zhichao; Keisman, Jennifer; Wu, May; Han, Jeongwoo; Dunn, Jennifer; Sullivan, John L.; Elgowainy, Amgad; Wang, Michael; Keisman, Jennifer

    2015-10-01

    The production of all forms of energy consumes water. To meet increased energy demands, it is essential to quantify the amount of water consumed in the production of different forms of energy. By analyzing the water consumed in different technologies, it is possible to identify areas for improvement in water conservation and reduce water stress in energy-producing regions. The transportation sector is a major consumer of energy in the United States. Because of the relationships between water and energy, the sustainability of transportation is tied to management of water resources. Assessment of water consumption throughout the life cycle of a fuel is necessary to understand its water resource implications. To perform a comparative life cycle assessment of transportation fuels, it is necessary first to develop an inventory of the water consumed in each process in each production supply chain. The Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model is an analytical tool that can used to estimate the full life-cycle environmental impacts of various transportation fuel pathways from wells to wheels. GREET is currently being expanded to include water consumption as a sustainability metric. The purpose of this report was to document data sources and methodologies to estimate water consumption factors (WCF) for the various transportation fuel pathways in GREET. WCFs reflect the quantity of freshwater directly consumed per unit production for various production processes in GREET. These factors do not include consumption of precipitation or low-quality water (e.g., seawater) and reflect only water that is consumed (i.e., not returned to the source from which it was withdrawn). The data in the report can be combined with GREET to compare the life cycle water consumption for different transportation fuels.

  17. More efficiency in fuel consumption using gearbox optimization based on Taguchi method

    NASA Astrophysics Data System (ADS)

    Goharimanesh, Masoud; Akbari, Aliakbar; Akbarzadeh Tootoonchi, Alireza

    2014-05-01

    Automotive emission is becoming a critical threat to today's human health. Many researchers are studying engine designs leading to less fuel consumption. Gearbox selection plays a key role in an engine design. In this study, Taguchi quality engineering method is employed, and optimum gear ratios in a five speed gear box is obtained. A table of various gear ratios is suggested by design of experiment techniques. Fuel consumption is calculated through simulating the corresponding combustion dynamics model. Using a 95 % confidence level, optimal parameter combinations are determined using the Taguchi method. The level of importance of the parameters on the fuel efficiency is resolved using the analysis of signal-to-noise ratio as well as analysis of variance.

  18. Dose reduction improvements in storage basins of spent nuclear fuel

    SciTech Connect

    Huang, Fan-Hsiung F.

    1997-08-13

    Spent nuclear fuel in storage basins at the Hanford Site has corroded and contaminated basin water, which has leaked into the soil; the fuel also had deposited a layer of radioactive sludge on basin floors. The SNF is to be removed from the basins to protect the nearby Columbia River. Because the radiation level is high, measures have been taken to reduce the background dose rate to as low as reasonably achievable (ALARA) to prevent radiation doses from becoming the limiting factor for removal of the SW in the basins to long-term dry storage. All activities of the SNF Project require application of ALARA principles for the workers. On the basis of these principles dose reduction improvements have been made by first identifying radiological sources. Principal radiological sources in the basin are basin walls, basin water, recirculation piping and equipment. Dose reduction activities focus on cleaning and coating basin walls to permit raising the water level, hydrolasing piping, and placing lead plates. In addition, the transfer bay floor will be refinished to make decontamination easier and reduce worker exposures in the radiation field. The background dose rates in the basin will be estimated before each task commences and after it is completed; these dose reduction data will provide the basis for cost benefit analysis.

  19. EMISSIONS REDUCTIONS USING HYDROGEN FROM PLASMATRON FUEL CONVERTERS

    SciTech Connect

    Bromberg, L

    2000-08-20

    Substantial progress in engine emission control is needed in order to meet present and proposed regulations for both spark ignition and diesel engines. Tightening regulations throughout the world reflect the ongoing concern with vehicle emissions. Recently developed compact plasmatron fuel converters have features that are suitable for onboard production of hydrogen for both fuel pretreatment and for exhaust aftertreatment applications. Systems that make use of these devices in conjunction with aftertreatment catalysts have the potential to improve significantly prospects for reduction of diesel engine emissions. Plasmatron fuel converters can provide a rapid response compact means to transform efficiently a wide range of hydrocarbon fuels into hydrogen rich gas. They have been used to reform natural gas [Bromberg1], gasoline [Green], diesel [Bromberg2] and hard-to-reform biofuels [Cohn1] into hydrogen rich gas (H2 + CO). The development of these devices has been pursued for the purpose of reducing engine exhaust pollutants by providing hydrogen rich gas for combustion in spark ignition and possibly diesel engines, as shown in Figure 1 [Cohn2]. Recent developments in compact plasmatron reformer design at MIT have resulted in substantial decreases in electrical power requirements. These new developments also increase the lifetime of the electrodes.

  20. Structural group analysis for soot reduction tendency of oxygenated fuels

    SciTech Connect

    Pepiot-Desjardins, P.; Pitsch, H.; Malhotra, R.; Kirby, S.R.; Boehman, A.L.

    2008-07-15

    Oxygenated additives are known to reduce soot formation in diesel engines. Numerous studies, both experimental and numerical, have reported that the reduction of particulate emissions depends on the molecular structure of the additives. In this paper, a structural group contribution approach is proposed to interpret experimental observations on the effect of oxygenated additives on the sooting propensities of hydrocarbon fuels. The statistically based method makes it possible to distinguish between chemical effects caused by the presence of oxygenated groups in the fuel mixture and mere dilution of the original fuel by the additive. The analysis was carried out on several experimental databases encompassing both premixed and nonpremixed configurations that include a new extensive set of smoke point measurements for mixtures of a given fuel with several oxygenated molecules. The current approach unifies the conclusions on the relative efficiency of the various oxygenated functionalities such as alcohols, esters, ethers, and carbonyl groups and provides a potential explanation for the seemingly contradictory trends exhibited by some raw experimental data. (author)

  1. Reduction potentials of total energy consumption and GHG emissions in Xiamen

    NASA Astrophysics Data System (ADS)

    Bin, C.; Cui, S.

    2009-12-01

    Urban areas contain 40% of the population and contribute 75% of the Chinese national economy. The 35 largest cities in China, which contain 18% of the population, contribute 40% of China’s energy uses and CO2 emissions. Therefore, an insight into energy consumption and quantification of emissions from urban areas are extremely important for identifying effects of energy-saving policies and finding solution to GHG emissions in urban centers. This paper applies the Long-range Energy Alternatives Planning (LEAP) system for modeling the total energy consumption and associated emissions from Xiamen city. Energy consumption under different sets of policy and technology options are analyzed for a time span of 2007-2020 and GHG emissions are estimated. Two scenarios have been designed to describe the future strategies relating to the development of Xiamen city. The ‘Business as Usual’ scenario is used as a baseline reference scenario, in which the government is assumed to do nothing to influence the long-term trends of urban energy demand. The ‘Integrated’ scenario is considered to be the most optimized case where a series of available reduction measures such as clean energy substitution, industrial energy conservation, combined heat and power generation, energy conservation in building, motor vehicle control and new and renewable energy development and utilization are assumed to be implemented. Energy demand and GHG emissions in Xiamen up to 2020 are estimated in these two scenarios. The total reduction potentials in the ‘Integrated’ scenario and the relative contribution rate of reduction potentials of each measure have been estimated.

  2. Overview of reductants utilized in nuclear fuel reprocessing/recycling

    SciTech Connect

    Patricia Paviet-Hartmann; Catherine Riddle; Keri Campbell; Edward Mausolf

    2013-10-01

    Most of the aqueous processes developed, or under consideration worldwide for the recycling of used nuclear fuel (UNF) utilize the oxido-reduction properties of actinides to separate them from other radionuclides. Generally, after acid dissolution of the UNF, (essentially in nitric acid solution), actinides are separated from the raffinate by liquid-liquid extraction using specific solvents, associated along the process, with a particular reductant that will allow the separation to occur. For example, the industrial PUREX process utilizes hydroxylamine as a plutonium reductant. Hydroxylamine has numerous advantages: not only does it have the proper attributes to reduce Pu(IV) to Pu(III), but it is also a non-metallic chemical that is readily decomposed to innocuous products by heating. However, it has been observed that the presence of high nitric acid concentrations or impurities (such as metal ions) in hydroxylamine solutions increase the likelihood of the initiation of an autocatalytic reaction. Recently there has been some interest in the application of simple hydrophilic hydroxamic ligands such as acetohydroxamic acid (AHA) for the stripping of tetravalent actinides in the UREX process flowsheet. This approach is based on the high coordinating ability of hydroxamic acids with tetravalent actinides (Np and Pu) compared with hexavalent uranium. Thus, the use of AHA offers a route for controlling neptunium and plutonium in the UREX process by complexant based stripping of Np(IV) and Pu(IV) from the TBP solvent phase, while U(VI) ions are not affected by AHA and remain solvated in the TBP phase. In the European GANEX process, AHA is also used to form hydrophilic complexes with actinides and strip them from the organic phase into nitric acid. However, AHA does not decompose completely when treated with nitric acid and hampers nitric acid recycling. In lieu of using AHA in the UREX + process, formohydroxamic acid (FHA), although not commercially available, hold

  3. Fuel Consumption Modeling of a Transport Category Aircraft Using Flight Operations Quality Assurance Data: A Literature Review

    NASA Technical Reports Server (NTRS)

    Stolzer, Alan J.

    2002-01-01

    Fuel is a major cost expense for air carriers. A typical airline spends 10% of its operating budget on the purchase of jet fuel, which even exceeds its expenditures on aircraft acquisitions. Thus, it is imperative that fuel consumption be managed as wisely as possible. The implementation of Flight Operations Quality Assurance (FOQA) programs at airlines may be able to assist in this management effort. The purpose of the study is to examine the literature regarding fuel consumption by air carriers, the literature related to air carrier fuel conservation efforts, and the literature related to the appropriate statistical methodologies to analyze the FOQA-derived data.

  4. Cold start fuel consumption of a diesel and a petrol car

    SciTech Connect

    Pearce, T.C.; Waters, M.H.L.

    1980-01-01

    Measurements have been made of the fuel consumption of a petrol and a diesel car when starting from cold. The cars were the 1.1 liter petrol VW Golf and the 1.5 liter diesel version, which have the same passenger accommodation and nearly identical road performance. It was found that the diesel car used less fuel in the warm-up period than the petrol, both when being driven at constant speed on a test track and with the engine idling and the car stationary. (Copyright (c) Crown Copyright 1980.)

  5. Study of operational parameters impacting helicopter fuel consumption. [using computer techniques (computer programs)

    NASA Technical Reports Server (NTRS)

    Cross, J. L.; Stevens, D. D.

    1976-01-01

    A computerized study of operational parameters affecting helicopter fuel consumption was conducted as an integral part of the NASA Civil Helicopter Technology Program. The study utilized the Helicopter Sizing and Performance Computer Program (HESCOMP) developed by the Boeing-Vertol Company and NASA Ames Research Center. An introduction to HESCOMP is incorporated in this report. The results presented were calculated using the NASA CH-53 civil helicopter research aircraft specifications. Plots from which optimum flight conditions for minimum fuel use that can be obtained are presented for this aircraft. The results of the study are considered to be generally indicative of trends for all helicopters.

  6. 75 FR 16422 - Plumas National Forest, California, Keddie Ridge Hazardous Fuels Reduction Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-01

    ... Forest Service Plumas National Forest, California, Keddie Ridge Hazardous Fuels Reduction Project AGENCY... impact statement (EIS) on the Keddie Ridge Hazardous Fuels Reduction Project proposal to modify fire... reduce the spread and introduction of noxious weeds through: fuels treatments, group selections,...

  7. Volume reduction of spent fuel elements for direct disposal

    SciTech Connect

    Wasserfuhr, I.C.

    1995-12-31

    The method of direct disposal of spent fuel elements provides the placing of fuel and non-fuel elements into the POLLUX final disposal casks. It is, however, necessary to disassemble the fuel elements into fuel rods and structural parts. While the fuel rods are condensed, the remaining structure is treated further with a 500-t skeleton press to minimize the volume.

  8. Assessment for fuel consumption and exhaust emissions of China's vehicles: future trends and policy implications.

    PubMed

    Wu, Yingying; Zhao, Peng; Zhang, Hongwei; Wang, Yuan; Mao, Guozhu

    2012-01-01

    In the recent years, China's auto industry develops rapidly, thus bringing a series of burdens to society and environment. This paper uses Logistic model to simulate the future trend of China's vehicle population and finds that China's auto industry would come into high speed development time during 2020-2050. Moreover, this paper predicts vehicles' fuel consumption and exhaust emissions (CO, HC, NO(x), and PM) and quantificationally evaluates related industry policies. It can be concluded that (1) by 2020, China should develop at least 47 million medium/heavy hybrid cars to prevent the growth of vehicle fuel consumption; (2) China should take the more stringent vehicle emission standard V over 2017-2021 to hold back the growth of exhaust emissions; (3) developing new energy vehicles is the most effective measure to ease the pressure brought by auto industry. PMID:23365524

  9. Assessment for Fuel Consumption and Exhaust Emissions of China's Vehicles: Future Trends and Policy Implications

    PubMed Central

    Zhao, Peng; Zhang, Hongwei; Wang, Yuan; Mao, Guozhu

    2012-01-01

    In the recent years, China's auto industry develops rapidly, thus bringing a series of burdens to society and environment. This paper uses Logistic model to simulate the future trend of China's vehicle population and finds that China's auto industry would come into high speed development time during 2020–2050. Moreover, this paper predicts vehicles' fuel consumption and exhaust emissions (CO, HC, NOx, and PM) and quantificationally evaluates related industry policies. It can be concluded that (1) by 2020, China should develop at least 47 million medium/heavy hybrid cars to prevent the growth of vehicle fuel consumption; (2) China should take the more stringent vehicle emission standard V over 2017–2021 to hold back the growth of exhaust emissions; (3) developing new energy vehicles is the most effective measure to ease the pressure brought by auto industry. PMID:23365524

  10. Using the Relationship between Vehicle Fuel Consumption and CO2 Emissions To Illustrate Chemical Principles

    NASA Astrophysics Data System (ADS)

    Oliver-Hoyo, Maria T.; Pinto, Gabriel

    2008-02-01

    This instructional resource utilizes consumer product information by which students compare theoretical stoichiometric calculations to CO 2 car emissions and fuel consumption data. Representing graphically the emission of CO 2 versus consumption of fuel provides a tangible way of connecting concepts studied in chemistry classes to everyday life. Considerable simplification of an otherwise complex chemistry problem provides comparable theoretical and actual data. Practice with unit conversion and graphing enhance this activity promoting skills used by professionals to perform emission measurements. This activity may be used to bring awareness of car emissions issues such as the environmental impact of CO 2 emissions and the differences of hybrid engines or gasoline versus diesel engines. Scientific literacy can be approached by incorporating exercises such as this one into chemistry classroom activities. Students have expressed keen interest in this type of "tangible" chemistry where a concrete example of everyday life puts textbook chemistry in context.

  11. Overview of reductants utilized in nuclear fuel reprocessing/recycling

    SciTech Connect

    Paviet-Hartmann, P.; Riddle, C.; Campbell, K.; Mausolf, E.

    2013-07-01

    The most widely used reductant to partition plutonium from uranium in the Purex process was ferrous sulfamate, other alternates were proposed such as hydrazine-stabilized ferrous nitrate or uranous nitrate, platinum catalyzed hydrogen, and hydrazine, hydroxylamine salts. New candidates to replace hydrazine or hydroxylamine nitrate (HAN) are pursued worldwide. They may improve the performance of the industrial Purex process towards different operations such as de-extraction of plutonium and reduction of the amount of hydrazine which will limit the formation of hydrazoic acid. When looking at future recycling technologies using hydroxamic ligands, neither acetohydroxamic acid (AHA) nor formohydroxamic acid (FHA) seem promising because they hydrolyze to give hydroxylamine and the parent carboxylic acid. Hydroxyethylhydrazine, HOC{sub 2}H{sub 4}N{sub 2}H{sub 3} (HEH) is a promising non-salt-forming reductant of Np and Pu ions because it is selective to neptunium and plutonium ions at room temperature and at relatively low acidity, it could serve as a replacement of HAN or AHA for the development of a novel used nuclear fuel recycling process.

  12. Potential benefits of solar reflective car shells: cooler cabins, fuel savings and emission reductions

    SciTech Connect

    Levinson, Ronnen; Pan, Heng; Ban-Weiss, George; Rosado, Pablo; Paolini, Riccardo; Akbari, Hashem

    2011-05-11

    Abstract: Vehicle thermal loads and air conditioning ancillary loads are strongly influenced by the absorption of solar energy. The adoption of solar reflective coatings for opaque surfaces of the vehicle shell can decrease the ?soak? temperature of the air in the cabin of a vehicle parked in the sun, potentially reducing the vehicle?s ancillary load and improving its fuel economy by permitting the use of a smaller air conditioner. An experimental comparison of otherwise identical black and silver compact sedans indicated that increasing the solar reflectance (?) of the car?s shell by about 0.5 lowered the soak temperature of breath-level air by about 5?6?C. Thermal analysis predicts that the air conditioning capacity required to cool the cabin air in the silver car to 25?C within 30min is 13percent less than that required in the black car. Assuming that potential reductions in AC capacity and engine ancillary load scale linearly with increase in shell solar reflectance, ADVISOR simulations of the SC03 driving cycle indicate that substituting a typical cool-colored shell (?=0.35) for a black shell (?=0.05) would reduce fuel consumption by 0.12L per 100km (1.1percent), increasing fuel economy by 0.10kmL?1 [0.24mpg] (1.1percent). It would also decrease carbon dioxide (CO2) emissions by 2.7gkm?1 (1.1percent), nitrogen oxide (NOx) emissions by 5.4mgkm?1 (0.44percent), carbon monoxide (CO) emissions by 17mgkm?1 (0.43percent), and hydrocarbon (HC) emissions by 4.1mgkm?1 (0.37percent). Selecting a typical white or silver shell (?=0.60) instead of a black shell would lower fuel consumption by 0.21L per 100km (1.9percent), raising fuel economy by 0.19kmL?1 [0.44mpg] (2.0percent). It would also decrease CO2 emissions by 4.9gkm?1 (1.9percent), NOx emissions by 9.9mgkm?1 (0.80percent), CO emissions by 31mgkm?1 (0.79percent), and HC emissions by 7.4mgkm?1 (0.67percent). Our simulations may underestimate emission reductions because emissions in standardized driving cycles are

  13. Effect of interactions between vehicles and pedestrians on fuel consumption and emissions

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Sun, Jian-Qiao

    2014-12-01

    This paper presents a study of variations of fuel consumption and emissions of vehicles due to random street crossings of pedestrians. The pedestrian and vehicle movement models as well as the interaction model between the two entities are presented. Extensive numerical simulations of single and multiple cars are carried out to investigate the traffic flow rate, vehicle average speed, fuel consumption, CO, HC and NOx emissions. Generally more noncompliant road-crossings of pedestrians lead to higher level of fuel consumptions and emissions of vehicles, and the traffic situation can be improved by imposing higher vehicle speed limit to some extent. Different traffic characteristics in low and high vehicle density regions are studied. The traffic flow is more influenced by crossing pedestrians in the low vehicle density region, while in the high vehicle density region, the interactions among vehicles dominate. The main contribution of this paper lies in the qualitative analysis of the impact of the interactions between pedestrians and vehicles on the traffic, its energy economy and emissions.

  14. High-Energy-Density Fuel Blending Strategies and Drop Dispersion for Fuel Cost Reduction and Soot Propensity Control

    NASA Technical Reports Server (NTRS)

    Bellan, J.; Harstad, K.

    1998-01-01

    The idea that low soot propensity of high-energy-density (HED) liquid sooting fuels and cost reduction of a multicomponent energetic fuel can be achieved by doping a less expensive, less sooting liquid fuel with HED is tested through numerical simulations.

  15. The Effect of Fuel Consumption on Cylinder Temperatures and Performance of a Cowled Wright J-5 Engine

    NASA Technical Reports Server (NTRS)

    Schey, Oscar W

    1929-01-01

    Given here are the results of tests made to determine the effect of fuel consumption on the cylinder temperatures and the performance of a cowled Wright J-5 engine. The results of these tests indicate that enriching the mixture by increasing the carburetor size results in a reduction in cylinder head and barrel temperatures. The cylinders shielded by the magnetos or the points on the cylinder that do not receive a free flow of cooling air increase most rapidly in temperature as the mixture is leaned. A free flow of air past the cylinders is essential for satisfactory operation on a lean mixture. The results of these tests show that the Wright J-5 engine can withstand severe temperatures for short periods of operation. The test results also show to what extent destructive temperatures may be avoided by enriching the mixture.

  16. JT9D-70/59 Improved High Pressure Turbine Active Clearance Control System. [for specific fuel consumption improvement

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.

    1979-01-01

    The JT9D-70/59 high pressure turbine active clearance control system was modified to provide reduction of blade tip clearance when the system is activated during cruise operation. The modification increased the flow capacity and air impingement effectiveness of the cooling air manifold to augment turbine case shrinkage capability, and increased responsiveness of the airseal clearance to case shrinkage. The simulated altitude engine testing indicated a significant improvement in specific fuel consumption with the modified system. A 1000 cycle engine endurance test showed no unusual wear or performance deterioration effects on the engine or the clearance control system. Rig tests indicated that the air impingement and seal support configurations used in the engine tests are near optimum.

  17. The Influence of Intersections on Fuel Consumption in Urban Arterial Road Traffic: A Single Vehicle Test in Harbin, China

    PubMed Central

    Wu, Lina; Ci, Yusheng; Chu, Jiangwei; Zhang, Hongsheng

    2015-01-01

    The calculating method for fuel consumption (FC) was put forward and calibrated and the characteristics of the fuel consumption on intersections were analyzed based on 18 groups of vehicular operating data which were acquired from the test experiment of a single vehicle along the urban arterial roads in Harbin, China. The results obtained show that 50.36% of the fuel consumption for the test vehicle was used at the area of intersections compared with 28.9% of the influencing distance and 68.5% of the running time; and 78.4% of them was burnt at the stages of acceleration and idling. Meanwhile, the type (c) of the vehicular operating status was illustrated to be the worst way of reducing fuel consumption, the causes were analyzed and four improvement strategies were put forward. PMID:26367012

  18. Cathodic oxygen reduction catalyzed by bacteria in microbial fuel cells.

    PubMed

    Rabaey, Korneel; Read, Suzanne T; Clauwaert, Peter; Freguia, Stefano; Bond, Philip L; Blackall, Linda L; Keller, Jurg

    2008-05-01

    Microbial fuel cells (MFCs) have the potential to combine wastewater treatment efficiency with energetic efficiency. One of the major impediments to MFC implementation is the operation of the cathode compartment, as it employs environmentally unfriendly catalysts such as platinum. As recently shown, bacteria can facilitate sustainable and cost-effective cathode catalysis for nitrate and also oxygen. Here we describe a carbon cathode open to the air, on which attached bacteria catalyzed oxygen reduction. The bacteria present were able to reduce oxygen as the ultimate electron acceptor using electrons provided by the solid-phase cathode. Current densities of up to 2.2 A m(-2) cathode projected surface were obtained (0.303+/-0.017 W m(-2), 15 W m(-3) total reactor volume). The cathodic microbial community was dominated by Sphingobacterium, Acinetobacter and Acidovorax sp., according to 16S rRNA gene clone library analysis. Isolates of Sphingobacterium sp. and Acinetobacter sp. were obtained using H(2)/O(2) mixtures. Some of the pure culture isolates obtained from the cathode showed an increase in the power output of up to three-fold compared to a non-inoculated control, that is, from 0.015+/-0.001 to 0.049+/-0.025 W m(-2) cathode projected surface. The strong decrease in activation losses indicates that bacteria function as true catalysts for oxygen reduction. Owing to the high overpotential for non-catalyzed reduction, oxygen is only to a limited extent competitive toward the electron donor, that is, the cathode. Further research to refine the operational parameters and increase the current density by modifying the electrode surface and elucidating the bacterial metabolism is warranted. PMID:18288216

  19. Long-lasting reduction in hippocampal neurogenesis by alcohol consumption in adolescent nonhuman primates.

    PubMed

    Taffe, Michael A; Kotzebue, Roxanne W; Crean, Rebecca D; Crawford, Elena F; Edwards, Scott; Mandyam, Chitra D

    2010-06-15

    Binge alcohol consumption in adolescents is increasing, and studies in animal models show that adolescence is a period of high vulnerability to brain insults. The purpose of the present study was to determine the deleterious effects of binge alcohol on hippocampal neurogenesis in adolescent nonhuman primates. Heavy binge alcohol consumption over 11 mo dramatically and persistently decreased hippocampal proliferation and neurogenesis. Combinatorial analysis revealed distinct, actively dividing hippocampal neural progenitor cell types in the subgranular zone of the dentate gyrus that were in transition from stem-like radial glia-like cells (type 1) to immature transiently amplifying neuroblasts (type 2a, type 2b, and type 3), suggesting the evolutionary conservation of milestones of neuronal development in macaque monkeys. Alcohol significantly decreased the number of actively dividing type 1, 2a, and 2b cell types without significantly altering the early neuronal type 3 cells, suggesting that alcohol interferes with the division and migration of hippocampal preneuronal progenitors. Furthermore, the lasting alcohol-induced reduction in hippocampal neurogenesis paralleled an increase in neural degeneration mediated by nonapoptotic pathways. Altogether, these results demonstrate that the hippocampal neurogenic niche during adolescence is highly vulnerable to alcohol and that alcohol decreases neuronal turnover in adolescent nonhuman primate hippocampus by altering the ongoing process of neuronal development. This lasting effect, observed 2 mo after alcohol discontinuation, may underlie the deficits in hippocampus-associated cognitive tasks that are observed in alcoholics. PMID:20534463

  20. Peak-Seeking Optimization of Trim for Reduced Fuel Consumption: Flight-test Results

    NASA Technical Reports Server (NTRS)

    Brown, Nelson Andrew; Schaefer, Jacob Robert

    2013-01-01

    A peak-seeking control algorithm for real-time trim optimization for reduced fuel consumption has been developed by researchers at the National Aeronautics and Space Administration (NASA) Dryden Flight Research Center to address the goals of the NASA Environmentally Responsible Aviation project to reduce fuel burn and emissions. The peak-seeking control algorithm is based on a steepest-descent algorithm using a time-varying Kalman filter to estimate the gradient of a performance function of fuel flow versus control surface positions. In real-time operation, deflections of symmetric ailerons, trailing-edge flaps, and leading-edge flaps of an F/A-18 airplane (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) are used for optimization of fuel flow. Results from six research flights are presented herein. The optimization algorithm found a trim configuration that required approximately 3 percent less fuel flow than the baseline trim at the same flight condition. The algorithm consistently rediscovered the solution from several initial conditions. These results show that the algorithm has good performance in a relevant environment.

  1. Peak-Seeking Optimization of Trim for Reduced Fuel Consumption: Flight-Test Results

    NASA Technical Reports Server (NTRS)

    Brown, Nelson Andrew; Schaefer, Jacob Robert

    2013-01-01

    A peak-seeking control algorithm for real-time trim optimization for reduced fuel consumption has been developed by researchers at the National Aeronautics and Space Administration (NASA) Dryden Flight Research Center to address the goals of the NASA Environmentally Responsible Aviation project to reduce fuel burn and emissions. The peak-seeking control algorithm is based on a steepest-descent algorithm using a time-varying Kalman filter to estimate the gradient of a performance function of fuel flow versus control surface positions. In real-time operation, deflections of symmetric ailerons, trailing-edge flaps, and leading-edge flaps of an F/A-18 airplane (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) are used for optimization of fuel flow. Results from six research flights are presented herein. The optimization algorithm found a trim configuration that required approximately 3 percent less fuel flow than the baseline trim at the same flight condition. The algorithm consistently rediscovered the solution from several initial conditions. These results show that the algorithm has good performance in a relevant environment.

  2. Using fuel cells or anode depolarization to reduce electrowinning energy consumption

    SciTech Connect

    Cook, G.M.

    1985-01-01

    Some existing and proposed metal electrowinning plant sites have hydrogen available to reduce the need for purchased energy. Hydrogen can reduce the energy consumption of electrowinning processes by depolarizing the anode; alternatively, it can be used in a fuel cell to generate dc electricity and heat at high efficiency. The use of H/sub 2/ to depolarize an anode in zinc electrowinning has been shown to reduce overall cell voltage by nearly 2 volts at 450 A/m/sup 2/. In a fuel cell, electricity can be produced with an efficiency of about 45 to 50% compared to about 30 to 32% for conventional generating equipment and the heat produced is available at temperatures which vary from about 150/sup 0/C for phosphoric acid fuel cells to 550 to 800/sup 0/C for advanced high temperature fuel cell systems. This paper examines the increased complexity that the depolarized anode and molten carbonate fuel cell technologies impose upon the electrowinning process, assesses the extent of energy savings that are available, and provides insight into the impact on capital and operating costs. 7 references.

  3. Influence of driving cycles on exhaust emissions and fuel consumption of gasoline passenger car in Bangkok.

    PubMed

    Nutramon, Tamsanya; Supachart, Chungpaibulpatana

    2009-01-01

    The influence of different driving cycles on their exhaust emissions and fuel consumption rate of gasoline passenger car was investigated in Bangkok based on the actual measurements obtained from a test vehicle driving on a standard chassis dynamometer. A newly established Bangkok driving cycle (BDC) and the European driving cycle (EDC) which is presently adopted as the legislative cycle for testing automobiles registered in Thailand were used. The newly developed BDC is constructed using the driving characteristic data obtained from the real on-road driving tests along selected traffic routes. A method for selecting appropriate road routes for real driving tests is also introduced. Variations of keyed driving parameters of BDC with different driving cycles were discussed. The results showed that the HC and CO emission factors of BDC are almost two and four times greater than those of EDC, respectively. Although the difference in the NOx emission factor is small, the value from BDC is still greater than that of EDC by 10%. Under BDC, the test vehicle consumes fuel about 25% more than it does under EDC. All these differences are mainly attributed to the greater proportion of idle periods and higher fluctuations of vehicle speed in the BDC cycle. This result indicated that the exhausted emissions and fuel consumption of vehicles obtained from tests under the legislative modal-type driving cycle (EDC) are significantly different from those actually produced under real traffic conditions especially during peak periods. PMID:20108661

  4. Dominance of sulfur-fueled iron oxide reduction in low-sulfate freshwater sediments.

    PubMed

    Hansel, Colleen M; Lentini, Chris J; Tang, Yuanzhi; Johnston, David T; Wankel, Scott D; Jardine, Philip M

    2015-11-01

    A central tenant in microbial biogeochemistry is that microbial metabolisms follow a predictable sequence of terminal electron acceptors based on the energetic yield for the reaction. It is thereby oftentimes assumed that microbial respiration of ferric iron outcompetes sulfate in all but high-sulfate systems, and thus sulfide has little influence on freshwater or terrestrial iron cycling. Observations of sulfate reduction in low-sulfate environments have been attributed to the presumed presence of highly crystalline iron oxides allowing sulfate reduction to be more energetically favored. Here we identified the iron-reducing processes under low-sulfate conditions within columns containing freshwater sediments amended with structurally diverse iron oxides and fermentation products that fuel anaerobic respiration. We show that despite low sulfate concentrations and regardless of iron oxide substrate (ferrihydrite, Al-ferrihydrite, goethite, hematite), sulfidization was a dominant pathway in iron reduction. This process was mediated by (re)cycling of sulfur upon reaction of sulfide and iron oxides to support continued sulfur-based respiration--a cryptic sulfur cycle involving generation and consumption of sulfur intermediates. Although canonical iron respiration was not observed in the sediments amended with the more crystalline iron oxides, iron respiration did become dominant in the presence of ferrihydrite once sulfate was consumed. Thus, despite more favorable energetics, ferrihydrite reduction did not precede sulfate reduction and instead an inverse redox zonation was observed. These findings indicate that sulfur (re)cycling is a dominant force in iron cycling even in low-sulfate systems and in a manner difficult to predict using the classical thermodynamic ladder. PMID:25871933

  5. Mobilizing Drug Consumption Rooms: inter-place networks and harm reduction drug policy.

    PubMed

    McCann, Eugene; Temenos, Cristina

    2015-01-01

    This article discusses the learning and politics involved in spreading Drug Consumption Rooms (DCRs) globally. DCRs are health facilities, operating under a harm reduction philosophy, where people consume illicit drugs in a supervised setting. Approximately 90 are located in almost 60 cities in 11 countries. They are intensely local attempts to improve the lives of specific populations and urban neighborhoods. DCRs are also global models that travel. This article examines the relationship between DCRs as facilities that are fixed in place and DCRs as globally-mobilized models of drug policy and public health practice. Drawing on research from seven countries, we apply concepts from the policy mobilities literature to analyze the travels of the DCR model and the political strategies involved in the siting of these public health service facilities. We detail the networked mobilization of the DCR model from Europe to Canada and Australia, the learning among facilities, the strategies used to mold the DCR model to local contexts, and the role of DCR staff in promoting continued proliferation of DCRs. We conclude by identifying some immobilities of DCRs to identify questions about practices, principles and future directions of harm reduction. PMID:25576837

  6. Power-law relationships for estimating mass, fuel consumption and costs of energy conversion equipments.

    PubMed

    Caduff, Marloes; Huijbregts, Mark A J; Althaus, Hans-Joerg; Hendriks, A Jan

    2011-01-15

    To perform life-cycle assessment studies, data on the production and use of the products is required. However, often only few data or measurements are available. Estimation of properties can be performed by applying scaling relationships. In many disciplines, they are used to either predict data or to search for underlying patterns, but they have not been considered in the context of product assessments hitherto. The goal of this study was to explore size scaling for commonly used energy conversion equipment, that is, boilers, engines, and generators. The variables mass M, fuel consumption Q, and costs C were related to power P. The established power-law relationships were M = 10(0.73.. 1.89)P(0.64.. 1.23) (R(2) ≥ 0.94), Q = 10(0.06.. 0.68)P(0.82.. 1.02) (R(2) ≥ 0.98) and C = 10(2.46.. 2.86)P(0.83.. 0.85) (R(2) ≥ 0.83). Mass versus power and costs versus power showed that none of the equipment types scaled isometrically, that is, with a slope of 1. Fuel consumption versus power scaled approximately isometrically for steam boilers, the other equipments scaled significantly lower than 1. This nonlinear scaling behavior induces a significant size effect. The power laws we established can be applied to scale the mass, fuel consumption and costs of energy conversion equipments up or down. Our findings suggest that empirical scaling laws can be used to estimate properties, particularly relevant in studies focusing on early product development for which generally only little information is available. PMID:21133374

  7. On board emission and fuel consumption measurement campaign on petrol-driven passenger cars

    NASA Astrophysics Data System (ADS)

    De Vlieger, I.

    Realistic emission and fuel consumption rates of petrol-driven cars were determined by on-the-road experiments in 1995. A validated, in-house developed, on-board measuring system was used. Six three-way catalyst (TWC) cars and one carburetted non-catalyst car were measured. The effects of road type, driving behaviour and cold start on CO, HC and NO x emissions and fuel consumption were analysed. In real traffic situations, emissions for TWC cars were found to be at least 70% lower than for the non-catalyst car. For TWC cars, emissions decreased across the board from city to rural and motorway traffic. Without a catalyst, motorway traffic resulted in the highest NO x emissions. Compared to normal driving, aggressive driving gave emissions which were up to four times higher. Except for NO x, calm driving resulted in lower emissions still. Comparable fuel consumption rates were obtained from normal and calm driving. Those from aggressive driving were higher, by as much as 40% in city traffic. Cold starts resulted in significantly higher CO and HC emission values than hot starts. These differences were less pronounced for NO x. Emissions from TWC cars were higher than generally expected, compared to the European emission limit values (91/441/EEC) and the emission factors used in Flanders and the Netherlands (Klein,1993) for the national emission inventories. Low-emitting cars during the emission test on a chassis dynamometer, as prescribed by the 91/441/EEC directive, did not necessarily give low emissions in real traffic situations.

  8. Fire Emissions Estimates in Siberia: Evaluation of Uncertainties in Area Burned, Land Cover, and Fuel Consumption

    NASA Astrophysics Data System (ADS)

    Kukavskaya, E.; Soja, A. J.; Ivanova, G. A.; Petkov, A.; Ponomarev, E. I.; Conard, S. G.

    2012-12-01

    Wildfire is one of the main disturbance factors in the boreal zone of Russia. Fires in the Russian boreal forest range from low-severity surface fires to high-severity crown fires. Estimates of carbon emissions from fires in Russia vary substantially due to differences in ecosystem classification and mapping, burned area calculations, and estimates of fuel consumption. We examined uncertainties in different parameters used to estimate biomass burning emissions. Several fire datasets (Institute of Forest burned area product, MCD45, MCD64, MOD14/MYD14, official data) were compared to estimate uncertainties in area burned in Siberia. Area burned was found to differ significantly by data source, with satellite data being by an order of magnitude greater than ground-based data. Differences between mapped ecosystems were also compared and contrasted on the basis of five land cover maps (GLC-2000, Globcover-2009, MODIS Collection 4 and 5 Global Land Cover, and the Digitized Ecosystem map of the Former Soviet Union) to evaluate the potential for error resulting from disparate vegetation structure and fuel consumption estimates. The examination of land cover maps showed that estimates of relative proportion of fire by ecosystem type varied substantially for the same year from map to map. Fuel consumption remains one of the main uncertainties in estimates of biomass burning emissions in Siberia. Accurate fuel consumption estimates are obtained in the course of fire experiments with pre- and post-fire biomass measuring. Our large-scale experiments carried out in the course of the FIRE BEAR (Fire Effects in the Boreal Eurasia Region) Project provided quantitative and qualitative data on ecosystem state and carbon emissions due to fires of known behavior in major forest types of Siberia that could be used to verify large-scale carbon emissions estimates. Global climate change is expected to result in increase of fire hazard and area burned, leading to impacts on global air

  9. High efficiency supercharger increases engine output, reduces fuel consumption through computer control

    SciTech Connect

    Kato, S.; Nakamura, N.; Kato, K.; Ohnaka, H.

    1986-01-01

    Efficiency of a supercharger mainly depends on the clearances between the rotors and the housing, but it has hitherto proved impossible to reduce the clearances without a strong possibility of seizure. A two lobe Roots type supercharger has been developed which overcomes this problem by means of a special resin coating on the rotors. As a result, an increase of 18% in volumetric efficiency of the supercharger is achieved. Engine torque is increased by 30%. Drive power loss resulting from the operation of a supercharger at partial load when boost was not required caused fuel consumption to increase by about 10%.

  10. Documentation for the personal computer version of the Motor Fuel Consumption Model

    SciTech Connect

    Not Available

    1985-12-03

    As part of an overall effort to increase the access to (and control of) analytical models by analysts within the DOE, the MFC model was recently reconfigured for use on a personal computer (PC). This report briefly summarizes the procedures for installing and operating the PC version of the MFC model. Section 2 provides an overview of the model framework and methodology. Software installation procedures are discussed in Section 3. Sections 4 through 10 present the procedures for operating the MFC model and outline typical fuel consumption impact analyses that can be performed with this tool.

  11. Remote fabrication and irradiation test of recycled nuclear fuel prepared by the oxidation and reduction of spent oxide fuel

    NASA Astrophysics Data System (ADS)

    Jin Ryu, Ho; Chan Song, Kee; Il Park, Geun; Won Lee, Jung; Seung Yang, Myung

    2005-02-01

    A direct dry recycling process was developed in order to reuse spent pressurized light water reactor (LWR) nuclear fuel in CANDU reactors without the separation of sensitive nuclear materials such as plutonium. The benefits of the dry recycling process are the saving of uranium resources and the reduction of spent fuel accumulation as well as a higher proliferation resistance. In the process of direct dry recycling, fuel pellets separated from spent LWR fuel rods are oxidized from UO2 to U3O8 at 500 °C in an air atmosphere and reduced into UO2 at 700 °C in a hydrogen atmosphere, which is called OREOX (oxidation and reduction of oxide fuel). The pellets are pulverized during the oxidation and reduction processes due to the phase transformation between cubic UO2 and orthorhombic U3O8. Using the oxide powder prepared from the OREOX process, the compaction and sintering processes are performed in a remote manner in a shielded hot cell due to the high radioactivity of the spent fuel. Most of the fission gas and volatile fission products are removed during the OREOX and sintering processes. The mini-elements fabricated by the direct dry recycling process are irradiated in the HANARO research reactor for the performance evaluation of the recycled fuel pellets. Post-irradiation examination of the irradiated fuel showed that microstructural evolution and fission gas release behavior of the dry-recycled fuel were similar to high burnup UO2 fuel.

  12. Cost and energy consumption estimates for the aluminum-air battery anode fuel cycle

    NASA Astrophysics Data System (ADS)

    1990-01-01

    At the request of DOE's Office of Energy Storage and Distribution (OESD), Pacific Northwest Laboratory (PNL) conducted a study to generate estimates of the energy use and costs associated with the aluminum anode fuel cycle of the aluminum-air (Al-air) battery. The results of this analysis indicate that the cost and energy consumption characteristics of the mechanically rechargeable Al-air battery system are not as attractive as some other electrically rechargeable electric vehicle battery systems being developed by OESD. However, there are distinct advantages to mechanically rechargeable batteries, which may make the Al-air battery (or other mechanically rechargeable batteries) attractive for other uses, such as stand-alone applications. Fuel cells, such as the proton exchange membrane (PEM), and advanced secondary batteries may be better suited to electric vehicle applications.

  13. Impact of the electric compressor for automotive air conditioning system on fuel consumption and performance analysis

    NASA Astrophysics Data System (ADS)

    Zulkifli, A. A.; Dahlan, A. A.; Zulkifli, A. H.; Nasution, H.; Aziz, A. A.; Perang, M. R. M.; Jamil, H. M.; Misseri, M. N.

    2015-12-01

    Air conditioning system is the biggest auxiliary load in a vehicle where the compressor consumed the largest. Problem with conventional compressor is the cooling capacity cannot be control directly to fulfill the demand of thermal load inside vehicle cabin. This study is conducted experimentally to analyze the difference of fuel usage and air conditioning performance between conventional compressor and electric compressor of the air conditioning system in automobile. The electric compressor is powered by the car battery in non-electric vehicle which the alternator will recharge the battery. The car is setup on a roller dynamometer and the vehicle speed is varied at 0, 30, 60, 90 and 110 km/h at cabin temperature of 25°C and internal heat load of 100 and 400 Watt. The results shows electric compressor has better fuel consumption and coefficient of performance compared to the conventional compressor.

  14. Opportunities and insights for reducing fossil fuel consumption by households and organizations

    NASA Astrophysics Data System (ADS)

    Stern, Paul C.; Janda, Kathryn B.; Brown, Marilyn A.; Steg, Linda; Vine, Edward L.; Lutzenhiser, Loren

    2016-05-01

    Realizing the ambitious commitments of the 2015 Paris Climate Conference (COP21) will require new ways of meeting human needs previously met by burning fossil fuels. Technological developments will be critical, but so will accelerated adoption of promising low-emission technologies and practices. National commitments will be more achievable if interventions take into account key psychological, social, cultural and organizational factors that influence energy choices, along with factors of an infrastructural, technical and economic nature. Broader engagement of social and behavioural science is needed to identify promising opportunities for reducing fossil fuel consumption. Here we discuss opportunities for change in households and organizations, primarily at short and intermediate timescales, and identify opportunities that have been underused in much of energy policy. Based on this survey, we suggest design principles for interventions by governments and other organizations, and identify areas of emphasis for future social science and interdisciplinary research.

  15. Cost and energy consumption estimates for the aluminum-air battery anode fuel cycle

    SciTech Connect

    Humphreys, K.K.; Brown, D.R.

    1990-01-01

    At the request of DOE's Office of Energy Storage and Distribution (OESD), Pacific Northwest Laboratory (PNL) conducted a study to generate estimates of the energy use and costs associated with the aluminum anode fuel cycle of the aluminum-air (Al-air) battery. The results of this analysis indicate that the cost and energy consumption characteristics of the mechanically rechargeable Al-air battery system are not as attractive as some other electrically rechargeable electric vehicle battery systems being developed by OESD. However, there are distinct advantages to mechanically rechargeable batteries, which may make the Al-air battery (or other mechanically rechargeable batteries) attractive for other uses, such as stand-alone applications. Fuel cells, such as the proton exchange membrane (PEM), and advanced secondary batteries may be better suited to electric vehicle applications. 26 refs., 3 figs., 25 tabs.

  16. Reduction in Post-Marathon Peak Oxygen Consumption: Sign of Cardiac Fatigue in Amateur Runners?

    PubMed Central

    Sierra, Ana Paula Rennó; da Silveira, Anderson Donelli; Francisco, Ricardo Contesini; Barretto, Rodrigo Bellios de Mattos; Sierra, Carlos Anibal; Meneghelo, Romeu Sergio; Kiss, Maria Augusta Peduti Dal Molin; Ghorayeb, Nabil; Stein, Ricardo

    2016-01-01

    Background Prolonged aerobic exercise, such as running a marathon, produces supraphysiological stress that can affect the athlete's homeostasis. Some degree of transient myocardial dysfunction ("cardiac fatigue") can be observed for several days after the race. Objective To verify if there are changes in the cardiopulmonary capacity, and cardiac inotropy and lusitropy in amateur marathoners after running a marathon. Methods The sample comprised 6 male amateur runners. All of them underwent cardiopulmonary exercise testing (CPET) one week before the São Paulo Marathon, and 3 to 4 days after that race. They underwent echocardiography 24 hours prior to and immediately after the marathon. All subjects were instructed not to exercise, to maintain their regular diet, ingest the same usual amount of liquids, and rest at least 8 hours a day in the period preceding the CPET. Results The athletes completed the marathon in 221.5 (207; 250) minutes. In the post-marathon CPET, there was a significant reduction in peak oxygen consumption and peak oxygen pulse compared to the results obtained before the race (50.75 and 46.35 mL.kg-1 .min-1; 19.4 and 18.1 mL.btm, respectively). The echocardiography showed a significant reduction in the s' wave (inotropic marker), but no significant change in the E/e' ratio (lusitropic marker). Conclusions In amateur runners, the marathon seems to promote changes in the cardiopulmonary capacity identified within 4 days after the race, with a reduction in the cardiac contractility. Such changes suggest that some degree of "cardiac fatigue" can occur. PMID:26760783

  17. 36 CFR 218.12 - Timing of authorized hazardous fuel reduction project decision.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... accordance with 40 CFR 1506.10, or DN may occur on, but not before, the fifth business day following the end... hazardous fuel reduction project decision. 218.12 Section 218.12 Parks, Forests, and Public Property FOREST... Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests...

  18. 36 CFR 218.12 - Timing of authorized hazardous fuel reduction project decision.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... accordance with 40 CFR 1506.10, or DN may occur on, but not before, the fifth business day following the end... hazardous fuel reduction project decision. 218.12 Section 218.12 Parks, Forests, and Public Property FOREST... Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests...

  19. 36 CFR 218.12 - Timing of authorized hazardous fuel reduction project decision.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... accordance with 40 CFR 1506.10, or DN may occur on, but not before, the fifth business day following the end... hazardous fuel reduction project decision. 218.12 Section 218.12 Parks, Forests, and Public Property FOREST... Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests...

  20. 36 CFR 218.4 - Authorized hazardous fuel reduction projects not subject to objection.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Authorized hazardous fuel reduction projects not subject to objection. 218.4 Section 218.4 Parks, Forests, and Public Property FOREST... Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests...

  1. 36 CFR 218.4 - Authorized hazardous fuel reduction projects not subject to objection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Authorized hazardous fuel reduction projects not subject to objection. 218.4 Section 218.4 Parks, Forests, and Public Property FOREST... Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests...

  2. 36 CFR 218.4 - Authorized hazardous fuel reduction projects not subject to objection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Authorized hazardous fuel reduction projects not subject to objection. 218.4 Section 218.4 Parks, Forests, and Public Property FOREST... Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests...

  3. Reductions in aircraft particulate emissions due to the use of Fischer-Tropsch fuels

    NASA Astrophysics Data System (ADS)

    Beyersdorf, A. J.; Timko, M. T.; Ziemba, L. D.; Bulzan, D.; Corporan, E.; Herndon, S. C.; Howard, R.; Miake-Lye, R.; Thornhill, K. L.; Winstead, E.; Wey, C.; Yu, Z.; Anderson, B. E.

    2013-06-01

    The use of alternative fuels for aviation is likely to increase due to concerns over fuel security, price stability and the sustainability of fuel sources. Concurrent reductions in particulate emissions from these alternative fuels are expected because of changes in fuel composition including reduced sulfur and aromatic content. The NASA Alternative Aviation Fuel Experiment (AAFEX) was conducted in January-February 2009 to investigate the effects of synthetic fuels on gas-phase and particulate emissions. Standard petroleum JP-8 fuel, pure synthetic fuels produced from natural gas and coal feedstocks using the Fischer-Tropsch (FT) process, and 50% blends of both fuels were tested in the CFM-56 engines on a DC-8 aircraft. To examine plume chemistry and particle evolution with time, samples were drawn from inlet probes positioned 1, 30, and 145 m downstream of the aircraft engines. No significant alteration to engine performance was measured when burning the alternative fuels. However, leaks in the aircraft fuel system were detected when operated with the pure FT fuels as a result of the absence of aromatic compounds in the fuel. Dramatic reductions in soot emissions were measured for both the pure FT fuels (reductions of 84% averaged over all powers) and blended fuels (64%) relative to the JP-8 baseline with the largest reductions at idle conditions. The alternative fuels also produced smaller soot (e.g. at 85% power, volume mean diameters were reduced from 78 nm for JP-8 to 51 nm for the FT fuel), which may reduce their ability to act as cloud condensation nuclei (CCN). The reductions in particulate emissions are expected for all alternative fuels with similar reductions in fuel sulfur and aromatic content regardless of the feedstock. As the plume cools downwind of the engine, nucleation-mode aerosols form. For the pure FT fuels, reductions (94% averaged over all powers) in downwind particle number emissions were similar to those measured at the exhaust plane (84

  4. Influence of fuel sulfur on the selective reduction of NO by NH/sub 3/

    SciTech Connect

    Lucas, D.; Brown, N.J.

    1981-10-01

    The selective reduction of NO by NH/sub 3/ addition has been studied in a lean-burning oil fired laboratory combustion tunnel with pyridine and thiophene added to the fuel oil. Two distinct, but interrelated effects were observed. The conversion of a fixed amount of fuel nitrogen to NO in the flame increased as the fuel sulfur concentration increased. In the post-combustion gases, there was a shift in the temperature dependence of the reduction process when the sulfur combustion products were present. The extent of the NO reduction was not significantly altered, but the optimum temperature for reduction shifted to higher values as the sulfur concentration increased.

  5. Fuel consumption and associated emissions from seagoing ships at berth derived from an on-board survey

    NASA Astrophysics Data System (ADS)

    Hulskotte, J. H. J.; Denier van der Gon, H. A. C.

    2010-03-01

    A methodology is presented to estimate the emissions of ships at berth based on their actual fuel consumption and the fuel quality. Accurate estimates of emissions from ships at berth demand reliable knowledge of the fuel consumption while at berth and associated fuel characteristics. However, assured information about energy use and fuel consumption of seagoing ships at berth is scarce. Proper estimation of ship emissions at berth is crucial for understanding the impact of shipping emissions on air quality and health in harbour cities as well as for a proper evaluation of the impact of abatement measures such as shore-side electricity and/or restrictions of sulphur content for shipping fuels to be used in ports. Therefore, a survey of energy consumption and fuel use on board of 89 seagoing ships was made in close cooperation with the Port of Rotterdam. Rotterdam is the major port of Europe ensuring that the results will have relevance for the larger European domain. On board of the ships at berth, a questionnaire was filled in by the chief engineer of that particular ship, assisted by two former mechanical shipping engineers employed at our organization. Survey results as well as the emission estimations are compared to the (scarce) information that is available and expert judgements in recent studies. The compiled survey data underlie the current Dutch emission estimation methodology for emissions of ships at berth.

  6. Seawater usable for production and consumption of hydrogen peroxide as a solar fuel

    PubMed Central

    Mase, Kentaro; Yoneda, Masaki; Yamada, Yusuke; Fukuzumi, Shunichi

    2016-01-01

    Hydrogen peroxide (H2O2) in water has been proposed as a promising solar fuel instead of gaseous hydrogen because of advantages on easy storage and high energy density, being used as a fuel of a one-compartment H2O2 fuel cell for producing electricity on demand with emitting only dioxygen (O2) and water. It is highly desired to utilize the most earth-abundant seawater instead of precious pure water for the practical use of H2O2 as a solar fuel. Here we have achieved efficient photocatalytic production of H2O2 from the most earth-abundant seawater instead of precious pure water and O2 in a two-compartment photoelectrochemical cell using WO3 as a photocatalyst for water oxidation and a cobalt complex supported on a glassy-carbon substrate for the selective two-electron reduction of O2. The concentration of H2O2 produced in seawater reached 48 mM, which was high enough to operate an H2O2 fuel cell. PMID:27142725

  7. Seawater usable for production and consumption of hydrogen peroxide as a solar fuel.

    PubMed

    Mase, Kentaro; Yoneda, Masaki; Yamada, Yusuke; Fukuzumi, Shunichi

    2016-01-01

    Hydrogen peroxide (H2O2) in water has been proposed as a promising solar fuel instead of gaseous hydrogen because of advantages on easy storage and high energy density, being used as a fuel of a one-compartment H2O2 fuel cell for producing electricity on demand with emitting only dioxygen (O2) and water. It is highly desired to utilize the most earth-abundant seawater instead of precious pure water for the practical use of H2O2 as a solar fuel. Here we have achieved efficient photocatalytic production of H2O2 from the most earth-abundant seawater instead of precious pure water and O2 in a two-compartment photoelectrochemical cell using WO3 as a photocatalyst for water oxidation and a cobalt complex supported on a glassy-carbon substrate for the selective two-electron reduction of O2. The concentration of H2O2 produced in seawater reached 48 mM, which was high enough to operate an H2O2 fuel cell. PMID:27142725

  8. Seawater usable for production and consumption of hydrogen peroxide as a solar fuel

    NASA Astrophysics Data System (ADS)

    Mase, Kentaro; Yoneda, Masaki; Yamada, Yusuke; Fukuzumi, Shunichi

    2016-05-01

    Hydrogen peroxide (H2O2) in water has been proposed as a promising solar fuel instead of gaseous hydrogen because of advantages on easy storage and high energy density, being used as a fuel of a one-compartment H2O2 fuel cell for producing electricity on demand with emitting only dioxygen (O2) and water. It is highly desired to utilize the most earth-abundant seawater instead of precious pure water for the practical use of H2O2 as a solar fuel. Here we have achieved efficient photocatalytic production of H2O2 from the most earth-abundant seawater instead of precious pure water and O2 in a two-compartment photoelectrochemical cell using WO3 as a photocatalyst for water oxidation and a cobalt complex supported on a glassy-carbon substrate for the selective two-electron reduction of O2. The concentration of H2O2 produced in seawater reached 48 mM, which was high enough to operate an H2O2 fuel cell.

  9. Monitoring of fuel consumption and aromatics formation in a kerosene spray flame as characterized by fluorescence spectroscopy.

    PubMed

    Allouis, C; Apicella, B; Barbella, R; Beretta, F; Ciajolo, A; Tregrossi, A

    2003-06-01

    The large presence of aromatic compounds in distillate fossil fuels should allow, in line of principle, to follow the fuel consumption and/or the presence of unburned fuel in a high temperature environment like a burner or the exhaust of combustion systems by exploiting the high fluorescence emission of aromatic fuel components. To this aim an UV-excited fluorescence source has to be used since the aromatic fuel components are strongly fluorescing in the UV region of the emission spectrum. In this work UV-excited laser induced fluorescence (LIF) diagnostics was applied to spray flames of kerosene in order to follow the fuel consumption and the formation of aromatic species. A strong UV signal was detected in the spray region of the flame that presented a shape similar to that found in the LIF spectra preliminary measured on the cold spray and in the room-temperature fluorescence of fuel solutions. The decrease of UV signal along the spray flame region was associated to the consumption of the fuel, but more difficult seems to be the attribution of a broad visible emission, that is present downstream of the flame. The visible emission feature could be assigned to flame-formed PAH species contained in the high molecular weight species, hypothesizing that their fluorescence spectra are shifted toward the visible for effect of the high temperature flame environment. PMID:12718975

  10. Modifying Alcohol Consumption among High School Students: An Efficacy Trial of an Alcohol Risk Reduction Program (PRIME for Life)

    ERIC Educational Resources Information Center

    Hallgren, Mats A.; Sjolund, Torbjorn; Kallmen, Hakan; Andreasson, Sven

    2011-01-01

    Purpose: PRIME for Life is an alcohol risk reduction program that has been used and refined in the USA for over 20 years. A Swedish version of the program has recently been adapted for use among Swedish high-school students (age 18-19). The objective of the study is to evaluate the effects of the program on youth alcohol consumption (including…

  11. Projected Impact of a Sodium Consumption Reduction Initiative in Argentina: An Analysis from the CVD Policy Model – Argentina

    PubMed Central

    Konfino, Jonatan; Mekonnen, Tekeshe A.; Coxson, Pamela G.; Ferrante, Daniel; Bibbins-Domingo, Kirsten

    2013-01-01

    Background Cardiovascular disease (CVD) is the leading cause of death in adults in Argentina. Sodium reduction policies targeting processed foods were implemented in 2011 in Argentina, but the impact has not been evaluated. The aims of this study are to use Argentina-specific data on sodium excretion and project the impact of Argentina’s sodium reduction policies under two scenarios - the 2-year intervention currently being undertaken or a more persistent 10 year sodium reduction strategy. Methods We used Argentina-specific data on sodium excretion by sex and projected the impact of the current strategy on sodium consumption and blood pressure decrease. We assessed the projected impact of sodium reduction policies on CVD using the Cardiovascular Disease (CVD) Policy Model, adapted to Argentina, modeling two alternative policy scenarios over the next decade. Results Our study finds that the initiative to reduce sodium consumption currently in place in Argentina will have substantial impact on CVD over the next 10 years. Under the current proposed policy of 2-year sodium reduction, the mean sodium consumption is projected to decrease by 319–387 mg/day. This decrease is expected to translate into an absolute reduction of systolic blood pressure from 0.93 mmHg to 1.81 mmHg. This would avert about 19,000 all-cause mortality, 13,000 total myocardial infarctions, and 10,000 total strokes over the next decade. A more persistent sodium reduction strategy would yield even greater CVD benefits. Conclusion The impact of the Argentinean initiative would be effective in substantially reducing mortality and morbidity from CVD. This paper provides evidence-based support to continue implementing strategies to reduce sodium consumption at a population level. PMID:24040085

  12. Study on Fuel Cell Network System Considering Reduction in Fuel Cell Capacity Using Load Leveling and Heat Release Loss

    NASA Astrophysics Data System (ADS)

    Obara, Shin'ya; Kudo, Kazuhiko

    Reduction in fuel cell capacity linked to a fuel cell network system is considered. When the power demand of the whole network is small, some of the electric power generated by the fuel cell is supplied to a water electrolysis device, and hydrogen and oxygen gases are generated. Both gases are compressed with each compressor and they are stored in cylinders. When the electric demand of the whole network is large, both gases are supplied to the network, and fuel cells are operated by these hydrogen and oxygen gases. Furthermore, an optimization plan is made to minimize the quantity of heat release of the hot water piping that connects each building. Such an energy network is analyzed assuming connection of individual houses, a hospital, a hotel, a convenience store, an office building, and a factory. Consequently, compared with the conventional system, a reduction of 46% of fuel cell capacity is expected.

  13. Pilot-scale equipment development for pyrochemical reduction of spent oxide fuel

    SciTech Connect

    Herrmann, S.D.; King, R.W.; Durstine, K.R.; Eberl, C.S.

    1998-07-01

    Argonne National Laboratory (ANL) has developed and is presently demonstrating the electrometallurgical conditioning of sodium-bonded spent metal fuel from Experimental Breeder Reactor II, resulting in uranium, ceramic, and metal waste forms. Equipment is being developed at ANL which will precondition irradiated oxide fuel and demonstrate the application of electrometallurgical conditioning to such non-metallic fuels as well. The oxide reduction process preconditions irradiated oxide fuel such that uranium and transuranic (TRU) constituents are chemically reduced into metallic form via a molten Li/LiCl-based reduction system. In this form the spent fuel is further conditioned in an electrorefiner and waste handling equipment, thereby placing the uranium, TRU elements, and fissions products into stable forms suitable for placement in a long-term repository. Development of the Li/LiCl-based oxide reduction process has proceeded at lab- (nominally 50 grams of heavy metal (HM)) and engineering-scale (nominally 10-kg of HM) for unirradiated oxide fuel. The presentation described the process and equipment design for scale-up from lab- and engineering-scale reduction of unirradiated oxide fuel in gloveboxes to pilot-scale (up to 100-kg of HM) reduction of irradiated oxide fuel in a hot cell. [Abstract only.

  14. Electrolytic Reduction of Spent Nuclear Oxide Fuel -- Effects of Fuel Form and Cathode Containment Materials on Bench-Scale Operations

    SciTech Connect

    S. D. Herrmann

    2007-09-01

    A collaborative effort between the Idaho National Laboratory (INL) and Korea Atomic Energy Research Institute (KAERI) is underway per an International Nuclear Energy Research Initiative to advance the development of a pyrochemical process for the treatment of spent nuclear oxide fuel. To assess the effects of specific process parameters that differ between oxide reduction operations at INL and KAERI, a series of 4 electrolytic reduction runs will be performed with a single salt loading of LiCl-Li2O at 650 °C using a test apparatus located inside of a hot cell at INL. The spent oxide fuel for the tests will be irradiated UO2 that has been subjected to a voloxidation process to form U3O8. The primary variables in the 4 electrolytic reduction runs will be fuel basket containment material and Li2O concentration in the LiCl salt. All 4 runs will be performed with comparable fuel loadings (approximately 50 g) and fuel compositions and will utilize a platinum anode and a Ni/NiO reference electrode. The first 2 runs will elucidate the effect of fuel form on the electrolytic reduction process by comparison of the above test results with U3O8 versus results from previous tests with UO2. The first 3 runs will investigate the impact that the cathode containment material has on the electrolytic reduction of spent oxide fuel. The 3rd and 4th runs will investigate the effect of Li2O concentration on the reduction process with a porous MgO cathode containment.

  15. Quantification of emission reduction potentials of primary air pollutants from residential solid fuel combustion by adopting cleaner fuels in China.

    PubMed

    Shen, Guofeng

    2015-11-01

    Residential low efficient fuel burning is a major source of many air pollutants produced during incomplete combustions, and household air pollution has been identified as one of the top environmental risk factors. Here we compiled literature-reported emission factors of pollutants including carbon monoxide (CO), total suspended particles (TSPs), PM2.5, organic carbon (OC), elemental carbon (EC) and polycyclic aromatic hydrocarbons (PAHs) for different household energy sources, and quantified the potential for emission reduction by clean fuel adoption. The burning of crop straws, firewood and coal chunks in residential stoves had high emissions per unit fuel mass but lower thermal efficiencies, resulting in high levels of pollution emissions per unit of useful energy, whereas pelletized biofuels and coal briquettes had lower pollutant emissions and higher thermal efficiencies. Briquetting coal may lead to 82%-88% CO, 74%-99% TSP, 73%-76% PM2.5, 64%-98% OC, 92%-99% EC and 80%-83% PAH reductions compared to raw chunk coal. Biomass pelletizing technology would achieve 88%-97% CO, 73%-87% TSP, 79%-88% PM2.5, 94%-96% OC, 91%-99% EC and 63%-96% PAH reduction compared to biomass burning. The adoption of gas fuels (i.e., liquid petroleum gas, natural gas) would achieve significant pollutant reduction, nearly 96% for targeted pollutants. The reduction is related not only to fuel change, but also to the usage of high efficiency stoves. PMID:26574082

  16. FINAL REPORT: Reduction in Energy Consumption and Variability in Steel Foundry Operations

    SciTech Connect

    F. Peters

    2005-05-24

    This project worked to improve the efficiency of the steel casting industry by reducing the variability that occurs because of process and product variation. The project focused on the post shakeout operations since roughly half of the production costs are in this area. These improvements will reduce the amount of variability, making it easier to manage the operation and improve the competitiveness. The reduction in variability will also reduce the need for many rework operations, which will result in a direct reduction of energy usage, particularly by the reduction of repeated heat treatment operations. Further energy savings will be realized from the reduction of scrap and reduced handling. Field studies were conducted at ten steel foundries that represented the U.S. steel casting industry, for a total of over 100 weeks of production observation. These studies quantified the amount of variability, and looked toward determining the source. A focus of the data collected was the grinding operations since this is a major effort in the cleaning room, and it represents the overall casting quality. The grinding was divided into two categories, expected and unexpected. Expected grinding is that in which the location of the effort is known prior to making the casting, such as smoothing parting lines, gates, and riser contacts. Unexpected grinding, which was approximately 80% of the effort, was done to improve the surfaces at weld repair locations, to rectify burnt on sand, and other surface anomalies at random locations. Unexpected grinding represents about 80% of the grinding effort. By quantifying this effort, the project raised awareness within the industry and the industry is continuing to make improvements. The field studies showed that the amount of variation of grinding operations (normalized because of the diverse set of parts studied) was very consistent across the industry. The field studies identified several specific sources that individually contributed to

  17. African crop yield reductions due to increasingly unbalanced Nitrogen and Phosphorus consumption

    NASA Astrophysics Data System (ADS)

    van der Velde, Marijn; Folberth, Christian; Balkovič, Juraj; Ciais, Philippe; Fritz, Steffen; Janssens, Ivan A.; Obersteiner, Michael; See, Linda; Skalský, Rastislav; Xiong, Wei; Peñuealas, Josep

    2014-05-01

    The impact of soil nutrient depletion on crop production has been known for decades, but robust assessments of the impact of increasingly unbalanced nitrogen (N) and phosphorus (P) application rates on crop production are lacking. Here, we use crop response functions based on 741 FAO maize crop trials and EPIC crop modeling across Africa to examine maize yield deficits resulting from unbalanced N:P applications under low, medium, and high input scenarios, for past (1975), current, and future N:P mass ratios of respectively, 1:0.29, 1:0.15, and 1:0.05. At low N inputs (10 kg/ha), current yield deficits amount to 10% but will increase up to 27% under the assumed future N:P ratio, while at medium N inputs (50 kg N/ha), future yield losses could amount to over 40%. The EPIC crop model was then used to simulate maize yields across Africa. The model results showed relative median future yield reductions at low N inputs of 40%, and 50% at medium and high inputs, albeit with large spatial variability. Dominant low-quality soils such as Ferralsols, which are strongly adsorbing P, and Arenosols with a low nutrient retention capacity, are associated with a strong yield decline, although Arenosols show very variable crop yield losses at low inputs. Optimal N:P ratios, i.e. those where the lowest amount of applied P produces the highest yield (given N input) where calculated with EPIC to be as low as 1:0.5. Finally, we estimated the additional P required given current N inputs, and given N inputs that would allow Africa to close yield gaps (ca. 70%). At current N inputs, P consumption would have to increase 2.3-fold to be optimal, and to increase 11.7-fold to close yield gaps. The P demand to overcome these yield deficits would provide a significant additional pressure on current global extraction of P resources.

  18. African crop yield reductions due to increasingly unbalanced Nitrogen and Phosphorus consumption.

    PubMed

    van der Velde, Marijn; Folberth, Christian; Balkovič, Juraj; Ciais, Philippe; Fritz, Steffen; Janssens, Ivan A; Obersteiner, Michael; See, Linda; Skalský, Rastislav; Xiong, Wei; Peñuelas, Josep

    2014-04-01

    The impact of soil nutrient depletion on crop production has been known for decades, but robust assessments of the impact of increasingly unbalanced nitrogen (N) and phosphorus (P) application rates on crop production are lacking. Here, we use crop response functions based on 741 FAO maize crop trials and EPIC crop modeling across Africa to examine maize yield deficits resulting from unbalanced N : P applications under low, medium, and high input scenarios, for past (1975), current, and future N : P mass ratios of respectively, 1 : 0.29, 1 : 0.15, and 1 : 0.05. At low N inputs (10 kg ha(-1)), current yield deficits amount to 10% but will increase up to 27% under the assumed future N : P ratio, while at medium N inputs (50 kg N ha(-1)), future yield losses could amount to over 40%. The EPIC crop model was then used to simulate maize yields across Africa. The model results showed relative median future yield reductions at low N inputs of 40%, and 50% at medium and high inputs, albeit with large spatial variability. Dominant low-quality soils such as Ferralsols, which are strongly adsorbing P, and Arenosols with a low nutrient retention capacity, are associated with a strong yield decline, although Arenosols show very variable crop yield losses at low inputs. Optimal N : P ratios, i.e. those where the lowest amount of applied P produces the highest yield (given N input) where calculated with EPIC to be as low as 1 : 0.5. Finally, we estimated the additional P required given current N inputs, and given N inputs that would allow Africa to close yield gaps (ca. 70%). At current N inputs, P consumption would have to increase 2.3-fold to be optimal, and to increase 11.7-fold to close yield gaps. The P demand to overcome these yield deficits would provide a significant additional pressure on current global extraction of P resources. PMID:24470387

  19. Is harm reduction profitable? An analytical framework for corporate social responsibility based on an epidemic model of addictive consumption.

    PubMed

    Massin, Sophie

    2012-06-01

    This article aims to help resolve the apparent paradox of producers of addictive goods who claim to be socially responsible while marketing a product clearly identified as harmful. It advances that reputation effects are crucial in this issue and that determining whether harm reduction practices are costly or profitable for the producers can help to assess the sincerity of their discourse. An analytical framework based on an epidemic model of addictive consumption that includes a deterrent effect of heavy use on initiation is developed. This framework enables us to establish a clear distinction between a simple responsible discourse and genuine harm reduction practices and, among harm reduction practices, between use reduction practices and micro harm reduction practices. Using simulations based on tobacco sales in France from 1950 to 2008, we explore the impact of three corresponding types of actions: communication on damage, restraining selling practices and development of safer products on total sales and on the social cost. We notably find that restraining selling practices toward light users, that is, preventing light users from escalating to heavy use, can be profitable for the producer, especially at early stages of the epidemic, but that such practices also contribute to increase the social cost. These results suggest that the existence of a deterrent effect of heavy use on the initiation of the consumption of an addictive good can shed new light on important issues, such as the motivations for corporate social responsibility and the definition of responsible actions in the particular case of harm reduction. PMID:22475402

  20. Contactless electric igniter for vehicle to lower exhaust emission and fuel consumption.

    PubMed

    Shen, Chih-Lung; Su, Jye-Chau

    2014-01-01

    An electric igniter for engine/hybrid vehicles is presented. The igniter comprises a flyback converter, a voltage-stacked capacitor, a PIC-based controller, a differential voltage detector, and an ignition coil, of which structure is non-contact type. Since the electric igniter adopts a capacitor to accumulate energy for engine ignition instead of traditional contacttype approach, it enhances the igniting performance of a spark plug effectively. As a result, combustion efficiency is promoted, fuel consumption is saved, and exhaust emission is reduced. The igniter not only is good for fuel efficiency but also can reduce HC and CO emission significantly, which therefore is an environmentally friendly product. The control core of the igniter is implemented on a single chip, which lowers discrete component count, reduces system volume, and increases reliability. In addition, the ignition timing can be programmed so that a timing regulator can be removed from the proposed system, simplifying its structure. To verify the feasibility and functionality of the igniter, key waveforms are measured and real-car experiments are performed as well. PMID:24672372

  1. Contactless Electric Igniter for Vehicle to Lower Exhaust Emission and Fuel Consumption

    PubMed Central

    Su, Jye-Chau

    2014-01-01

    An electric igniter for engine/hybrid vehicles is presented. The igniter comprises a flyback converter, a voltage-stacked capacitor, a PIC-based controller, a differential voltage detector, and an ignition coil, of which structure is non-contact type. Since the electric igniter adopts a capacitor to accumulate energy for engine ignition instead of traditional contacttype approach, it enhances the igniting performance of a spark plug effectively. As a result, combustion efficiency is promoted, fuel consumption is saved, and exhaust emission is reduced. The igniter not only is good for fuel efficiency but also can reduce HC and CO emission significantly, which therefore is an environmentally friendly product. The control core of the igniter is implemented on a single chip, which lowers discrete component count, reduces system volume, and increases reliability. In addition, the ignition timing can be programmed so that a timing regulator can be removed from the proposed system, simplifying its structure. To verify the feasibility and functionality of the igniter, key waveforms are measured and real-car experiments are performed as well. PMID:24672372

  2. Evaluation of fuel consumption potential of medium and heavy duty vehicles through modeling and simulation.

    SciTech Connect

    Delorme, A.; Karbowski, D.; Sharer, P.; Energy Systems

    2010-03-31

    The main objective of this report is to provide quantitative data to support the Committee in its task of establishing a report to support rulemaking on medium- and heavy-duty fuel efficiency improvement. In particular, it is of paramount importance for the Committee to base or illustrate their conclusions on established models and actual state-of-the art data. The simulations studies presented in the report have been defined and requested by the members of the National Academy committee to provide quantitative inputs to support their recommendations. As such, various technologies and usage scenarios were considered for several applications. One of the objective is to provide the results along with their associated assumptions (both vehicle and drive cycles), information generally missing from public discussions on literature search. Finally, the advantages and limitations of using simulation will be summarized. The study addresses several of the committee tasks, including: (1) Discussion of the implication of metric selection; (2) Assessing the impact of existing technologies on fuel consumption through energy balance analysis (both steady-state and standard cycles) as well as real world drive cycles; and (3) Impact of future technologies, both individually and collectively.

  3. Quantitative Effects of Vehicle Parameters on Fuel Consumption for Heavy-Duty Vehicle

    SciTech Connect

    Wang, Lijuan; Kelly, Kenneth; Walkowicz, Kevin; Duran, Adam

    2015-10-16

    The National Renewable Energy Laboratory's (NREL's) Fleet Test and Evaluations team recently conducted chassis dynamometer tests of a class 8 conventional regional delivery truck over the Heavy Heavy-Duty Diesel Truck (HHDDT), West Virginia University City (WVU City), and Composite International Truck Local and Commuter Cycle (CILCC) drive cycles. A quantitative study was conducted by analyzing the impacts of various factors on fuel consumption (FC) and fuel economy (FE) by modeling and simulating the truck using NREL's Future Automotive Systems Technology Simulator (FASTSim). Factors used in this study included vehicle weight, and the coefficients of rolling resistance and aerodynamic drag. The simulation results from a single parametric study revealed that FC was approximately a linear function of the weight, coefficient of aerodynamic drag, and rolling resistance over various drive cycles. Among these parameters, the truck weight had the largest effect on FC. The study of the impact of two technologies on FE suggested that, depending on the circumstances, it may be more cost effective to reduce one parameter (such as coefficient of aerodynamic drag) to increase fuel economy, or it may be more beneficial to reduce another (such as the coefficient of rolling resistance). It also provided a convenient way to estimate FE by interpolating within the parameter values and extrapolating outside of them. The simulation results indicated that the FC could be reduced from 38.70 L/100 km, 50.72 L/100 km, and 38.42 L/100 km in the baseline truck to 26.78 L/100 km, 43.14 L/100 km and 29.84 L/100 km over the HHDDT, WVU City and CILCC drive cycles, respectively, when the U.S. Department of Energy's three targeted new technologies were applied simultaneously.

  4. The national Fire and Fire Surrogate study: Effects of fuel reduction methods on forest vegetation structure and fuels

    USGS Publications Warehouse

    Schwilk, D.W.; Keeley, J.E.; Knapp, E.E.; Mciver, J.; Bailey, J.D.; Fettig, C.J.; Fiedler, C.E.; Harrod, R.J.; Moghaddas, J.J.; Outcalt, K.W.; Skinner, C.N.; Stephens, S.L.; Waldrop, T.A.; Yaussy, D.A.; Youngblood, A.

    2009-01-01

    Changes in vegetation and fuels were evaluated from measurements taken before and after fuel reduction treatments (prescribed fire, mechanical treatments, and the combination of the two) at 12 Fire and Fire Surrogate (FFS) sites located in forests with a surface fire regime across the conterminous United States. To test the relative effectiveness of fuel reduction treatments and their effect on ecological parameters we used an informationtheoretic approach on a suite of 12 variables representing the overstory (basal area and live tree, sapling, and snag density), the understory (seedling density, shrub cover, and native and alien herbaceous species richness), and the most relevant fuel parameters for wildfire damage (height to live crown, total fuel bed mass, forest floor mass, and woody fuel mass). In the short term (one year after treatment), mechanical treatments were more effective at reducing overstory tree density and basal area and at increasing quadratic mean tree diameter. Prescribed fire treatments were more effective at creating snags, killing seedlings, elevating height to live crown, and reducing surface woody fuels. Overall, the response to fuel reduction treatments of the ecological variables presented in this paper was generally maximized by the combined mechanical plus burning treatment. If the management goal is to quickly produce stands with fewer and larger diameter trees, less surface fuel mass, and greater herbaceous species richness, the combined treatment gave the most desirable results. However, because mechanical plus burning treatments also favored alien species invasion at some sites, monitoring and control need to be part of the prescription when using this treatment. ?? 2009 by the Ecological Society of America.

  5. Coal fueled ported kiln direct reduction process in Norway

    SciTech Connect

    Rierson, D.W.

    1994-12-31

    Allis Mineral Systems (AMS), formerly the minerals processing group at Allis-Chalmers Corporation, developed a ported kiln process in the 1960`s specifically for the direct reduction of iron ore. The process is called ACCAR. This ported kiln technology has more recently been coupled with AMS` GRATE-KILN System for iron oxide pelletizing into the GRATE-CAR Process, for minerals reduction. The GRATE-CAR Process can handle a fine grained ore concentrate through the steps of agglomeration, induration and reduction in a single production line.

  6. 36 CFR 218.3 - Authorized hazardous fuel reduction projects subject to objection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests Restoration... reduction projects are approved contemporaneously with a plan amendment that applies only to that project, the objection process of this part applies to both the plan amendment and the project....

  7. 36 CFR 218.3 - Authorized hazardous fuel reduction projects subject to objection.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests Restoration... reduction projects are approved contemporaneously with a plan amendment that applies only to that project, the objection process of this part applies to both the plan amendment and the project....

  8. 36 CFR 218.3 - Authorized hazardous fuel reduction projects subject to objection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests Restoration... reduction projects are approved contemporaneously with a plan amendment that applies only to that project, the objection process of this part applies to both the plan amendment and the project....

  9. Delayed conifer mortality after fuel reduction treatments: Interactive effects of fuel, fire intensity, and bark beetles

    USGS Publications Warehouse

    Youngblood, A.; Grace, J.B.; Mciver, J.D.

    2009-01-01

    Many low-elevation dry forests of the western United States contain more small trees and fewer large trees, more down woody debris, and less diverse and vigorous understory plant communities compared to conditions under historical fire regimes. These altered structural conditions may contribute to increased probability of unnaturally severe wildfires, susceptibility to uncharacteristic insect outbreaks, and drought-related mortality. Broad-scale fuel reduction and restoration treatments are proposed to promote stand development on trajectories toward more sustainable structures. Little research to date, however, has quantified the effects of these treatments on the ecosystem, especially delayed and latent tree mortality resulting directly or indirectly from treatments. In this paper, we explore complex hypotheses relating to the cascade of effects that influence ponderosa pine (Pinus ponderosa) and Douglas-fir (Pseudotsuga menziesii) mortality using structural equation modeling (SEM). We used annual census and plot data through six growing seasons after thinning and four growing seasons after burning from a replicated, operational-scale, completely randomized experiment conducted in northeastern Oregon, USA, as part of the national Fire and Fire Surrogate study. Treatments included thin, burn, thin followed by burn (thin+burn), and control. Burn and thin+burn treatments increased the proportion of dead trees while the proportion of dead trees declined or remained constant in thin and control units, although the density of dead trees was essentially unchanged with treatment. Most of the new mortality (96%) occurred within two years of treatment and was attributed to bark beetles. Bark beetle-caused tree mortality, while low overall, was greatest in thin + burn treatments. SEM results indicate that the probability of mortality of large-diameter ponderosa pine from bark beetles and wood borers was directly related to surface fire severity and bole charring, which in

  10. Changes in alcohol consumption in Denmark after the tax reduction on spirits

    PubMed Central

    Grittner, Ulrike; Gustafsson, Nina-Katri; Bloomfield, Kim

    2010-01-01

    AIMS This paper examines changes in alcohol consumption in Denmark between 2003 and 2006 after the excise tax on spirits in Denmark was lowered by 45% on 1. October 2003 and travelers’ allowances for alcohol import were increased on 1. January 2004. METHODS Cross-sectional and panel data from Denmark from 2003 to 2006 were analyzed. Samples were collected by telephone interviews using random digit dialing. RESULTS Panel data for Denmark revealed that alcohol consumption remained relatively stable. Similar results were found in the Danish cross-sectional data. It appears that substitution rather than increased importation occurred. CONCLUSION We found no evidence to support earlier research stating that decreased prices and increased availability is related to higher alcohol consumption. This could be partly because Denmark has reached a “saturation” level of consumption over the past 30 years, but also because the survey mode of data collection did not capture specific sub-populations who might have increased their consumption. Other indicators of alcohol use or alcohol-related harm may be necessary to examine in order to fully assess the consequences of such changes in alcohol availability. PMID:19776586

  11. The Utility of Fire Radiative Energy for Understanding Fuel Consumption due to Wildfire in Boreal Peatlands

    NASA Astrophysics Data System (ADS)

    Banskota, A.; Falkowski, M. J.; Kane, E. S.; Smith, A. M.

    2014-12-01

    Radiative energy from active fire has been found to correlate well with the amount of fuel consumed during the lifetime of a fire event. Fire radiative power (FRP) detected by sensors onboard MODIS satellites may therefore provide direct estimates of CO2 emissions related to biomass burning. Less known is the ability of satellite data to detect active fire from predominantly smoldering burns in boreal peatlands. Boreal peatlands store a large amount of soil carbon that is likely to become increasingly vulnerable to wildfire as climate change lowers water tables and exposes C-rich peat to burning. In this study, we investigate the utility of fire radiative energy (FRE) to estimate fuel consumption associated with wildfire in 2004 in boreal peatlands in Alaska. FRE values are generally estimated from FRP retrieved at detected active fire locations and times by summing the FRP values multiplied by the time difference between acquisitions. One central issue in deriving reliable FRE estimates by such approach is the requirement for sufficient sampling of the FRP to capture spatiotemporal variability in the fire. Our preliminary analysis confirms that the detection of active fire in peatlands are indeed not spatially exhaustive and temporally continuous. Thus we are further investigating the fusion of instantaneous FRP from MODIS active fire detection with the MODIS burned area product to derive FRE estimates across the burned area. We are following a previously tested strategy for such fusion for temporal integration of instantaneous FRP to derive FRE and spatial extrapolation of FRE over the burned area. The FRE estimates are then related to ground-measured peatland burn depths across different wildfire locations. The results of this study will ultimately indicate the utility of MODIS fire products for providing reliable biomass burned estimates in boreal peatlands.

  12. On-road pollutant emission and fuel consumption characteristics of buses in Beijing.

    PubMed

    Wang, Aijuan; Ge, Yunshan; Tan, Jianwei; Fu, Mingliang; Shah, Asad Naeem; Ding, Yan; Zhao, Hong; Liang, Bin

    2011-01-01

    On-road emission and fuel consumption (FC) levels for Euro III and IV buses fueled on diesel and compressed natural gas (CNG) were compared, and emission and FC characteristics of buses were analyzed based on approximately 28,700 groups of instantaneous data obtained in Beijing using a portable emissions measurement system (PEMS). The experimental results revealed that NOx and PM emissions from CNG buses were decreased by 72.0% and 82.3% respectively, compared with Euro IV diesel buses. Similarly, these emissions were reduced by 75.2% and 96.3% respectively, compared with Euro III diesel buses. In addition, CO2, CO, HC, NOx, PM emissions and FC of Euro IV diesel buses were reduced by 26.4%, 75.2%, 73.6%, 11.4%, 79.1%, and 26.0%, respectively, relative to Euro III diesel buses. The CO2, CO, HC, NOx, PM emissions and FC factors all decreased with bus speed increased, while increased as bus acceleration increased. At the same time, the emission/FC rates as well as the emission/FC factors exhibited a strong positive correlation with the vehicle specific power (VSP). They all were the lowest when VSP < 0, and then rapidly increased as VSP increased. Furthermore, both the emission/FC rates and emission/FC factors were the highest at accelerations, higher at cruise speeds, and the lowest at decelerations for non-idling buses. These results can provide a base reference to further estimate bus emission and FC inventories in Beijing. PMID:21520811

  13. Reductions in aircraft particulate emissions due to the use of Fischer-Tropsch fuels

    NASA Astrophysics Data System (ADS)

    Beyersdorf, A. J.; Timko, M. T.; Ziemba, L. D.; Bulzan, D.; Corporan, E.; Herndon, S. C.; Howard, R.; Miake-Lye, R.; Thornhill, K. L.; Winstead, E.; Wey, C.; Yu, Z.; Anderson, B. E.

    2014-01-01

    The use of alternative fuels for aviation is likely to increase due to concerns over fuel security, price stability, and the sustainability of fuel sources. Concurrent reductions in particulate emissions from these alternative fuels are expected because of changes in fuel composition including reduced sulfur and aromatic content. The NASA Alternative Aviation Fuel Experiment (AAFEX) was conducted in January-February 2009 to investigate the effects of synthetic fuels on gas-phase and particulate emissions. Standard petroleum JP-8 fuel, pure synthetic fuels produced from natural gas and coal feedstocks using the Fischer-Tropsch (FT) process, and 50% blends of both fuels were tested in the CFM-56 engines on a DC-8 aircraft. To examine plume chemistry and particle evolution with time, samples were drawn from inlet probes positioned 1, 30, and 145 m downstream of the aircraft engines. No significant alteration to engine performance was measured when burning the alternative fuels. However, leaks in the aircraft fuel system were detected when operated with the pure FT fuels as a result of the absence of aromatic compounds in the fuel. Dramatic reductions in soot emissions were measured for both the pure FT fuels (reductions in mass of 86% averaged over all powers) and blended fuels (66%) relative to the JP-8 baseline with the largest reductions at idle conditions. At 7% power, this corresponds to a reduction from 7.6 mg kg-1 for JP-8 to 1.2 mg kg-1 for the natural gas FT fuel. At full power, soot emissions were reduced from 103 to 24 mg kg-1 (JP-8 and natural gas FT, respectively). The alternative fuels also produced smaller soot (e.g., at 85% power, volume mean diameters were reduced from 78 nm for JP-8 to 51 nm for the natural gas FT fuel), which may reduce their ability to act as cloud condensation nuclei (CCN). The reductions in particulate emissions are expected for all alternative fuels with similar reductions in fuel sulfur and aromatic content regardless of the

  14. Aerodynamic Improvements of an Empty Timber Truck can Have the Potential of Significantly Reducing Fuel Consumption

    NASA Astrophysics Data System (ADS)

    Andersson, Magnus; Marashi, Seyedeh Sepideh; Karlsson, Matts

    2012-11-01

    In the present study, aerodynamic drag (AD) has been estimated for an empty and a fully loaded conceptual timber truck (TT) using Computational Fluid Dynamics (CFD). The increasing fuel prices have challenged heavy duty vehicle (HDV) manufactures to strive for better fuel economy, by e.g. utilizing drag reducing external devices. Despite this knowledge, the TT fleets seem to be left in the dark. Like HDV aerodynamics, similarities can be observed as a large low pressure wake is formed behind the tractor (unloaded) and downstream of the trailer (full load) thus generating AD. As TTs travel half the time without any cargo, focus on drag reduction is important. The full scaled TTs where simulated using the realizable k-epsilon model with grid adaption techniques for mesh independence. Our results indicate that a loaded TT reduces the AD significantly as both wake size and turbulence kinetic energy are lowered. In contrast to HDV the unloaded TTs have a much larger design space available for possible drag reducing devices, e.g. plastic wrapping and/or flaps. This conceptual CFD study has given an indication of the large AD difference between the unloaded and fully loaded TT, showing the potential for significant AD improvements.

  15. Fuel reduction management practices in riparian areas of the Western USA.

    PubMed

    Stone, Katharine R; Pilliod, David S; Dwire, Kathleen A; Rhoades, Charles C; Wollrab, Sherry P; Young, Michael K

    2010-07-01

    Two decades of uncharacteristically severe wildfires have caused government and private land managers to actively reduce hazardous fuels to lessen wildfire severity in western forests, including riparian areas. Because riparian fuel treatments are a fairly new management strategy, we set out to document their frequency and extent on federal lands in the western U.S. Seventy-four USDA Forest Service Fire Management Officers (FMOs) in 11 states were interviewed to collect information on the number and characteristics of riparian fuel reduction treatments in their management district. Just under half of the FMOs surveyed (43%) indicated that they were conducting fuel reduction treatments in riparian areas. The primary management objective listed for these projects was either fuel reduction (81%) or ecological restoration and habitat improvement (41%), though multiple management goals were common (56%). Most projects were of small extent (93% < 300 acres), occurred in the wildland-urban interface (75%), and were conducted in ways to minimize negative impacts on species and habitats. The results of this survey suggest that managers are proceeding cautiously with treatments. To facilitate project planning and implementation, managers recommended early coordination with resource specialists, such as hydrologists and fish and wildlife biologists. Well-designed monitoring of the consequences of riparian fuel treatments on fuel loads, fire risk, and ecological effects is needed to provide a scientifically-defensible basis for the continued and growing implementation of these treatments. PMID:20499233

  16. Using oily wastewater emulsified fuel in boiler: energy saving and reduction of air pollutant emissions.

    PubMed

    Chen, Chun-Chi; Lee, Wen-Jhy

    2008-01-01

    The limited data for using emulsified oil have demonstrated its effectiveness in reducing flue gas pollutant emissions. The presence of a high concentration of toxic organic compounds in industrial wastewaters always presents significant problems. Therefore, this study was undertaken by using wastewater with COD of 9600 mg/L and total petroleum hydrocarbons-gasoline 440 mg/L for making an emulsified oil (wastewater content 20% with 0.1% surfactant) to evaluate the extent of reductions in both criteria pollutants and polycyclic aromatic hydrocarbons. For comparison, two other systems (heavy oil fuel and water-emulsified oil) were also conducted. The wastewater-emulsified oil fuel results in significant reductions in particulate matter (PM), NO(x), SO2, and CO as compared to heavy oil fuel and similar to those from water/oil emulsified fuel; for PM, it is better in wastewater-emulsified oil. The reductions of total PAH flue gas emissions are 38 and 30% for wastewater- and water-emulsified fuel, respectively; they are 63 and 44% for total BaP(eq), respectively. In addition to reducing flue gas pollutant emissions, the results also demonstrate that the use of wastewater-emulsified fuel in boiler operation provides several advantages: (1) safe disposal of industrial wastewater; and (2) energy savings of about 13%. Thus, wastewater/oil-emulsified fuel is highly suitable for use in boilers. PMID:18350907

  17. Fuel Reduction Management Practices in Riparian Areas of the Western USA

    NASA Astrophysics Data System (ADS)

    Stone, Katharine R.; Pilliod, David S.; Dwire, Kathleen A.; Rhoades, Charles C.; Wollrab, Sherry P.; Young, Michael K.

    2010-07-01

    Two decades of uncharacteristically severe wildfires have caused government and private land managers to actively reduce hazardous fuels to lessen wildfire severity in western forests, including riparian areas. Because riparian fuel treatments are a fairly new management strategy, we set out to document their frequency and extent on federal lands in the western U.S. Seventy-four USDA Forest Service Fire Management Officers (FMOs) in 11 states were interviewed to collect information on the number and characteristics of riparian fuel reduction treatments in their management district. Just under half of the FMOs surveyed (43%) indicated that they were conducting fuel reduction treatments in riparian areas. The primary management objective listed for these projects was either fuel reduction (81%) or ecological restoration and habitat improvement (41%), though multiple management goals were common (56%). Most projects were of small extent (93% < 300 acres), occurred in the wildland-urban interface (75%), and were conducted in ways to minimize negative impacts on species and habitats. The results of this survey suggest that managers are proceeding cautiously with treatments. To facilitate project planning and implementation, managers recommended early coordination with resource specialists, such as hydrologists and fish and wildlife biologists. Well-designed monitoring of the consequences of riparian fuel treatments on fuel loads, fire risk, and ecological effects is needed to provide a scientifically-defensible basis for the continued and growing implementation of these treatments.

  18. Spent nuclear fuel recycling with plasma reduction and etching

    DOEpatents

    Kim, Yong Ho

    2012-06-05

    A method of extracting uranium from spent nuclear fuel (SNF) particles is disclosed. Spent nuclear fuel (SNF) (containing oxides of uranium, oxides of fission products (FP) and oxides of transuranic (TRU) elements (including plutonium)) are subjected to a hydrogen plasma and a fluorine plasma. The hydrogen plasma reduces the uranium and plutonium oxides from their oxide state. The fluorine plasma etches the SNF metals to form UF6 and PuF4. During subjection of the SNF particles to the fluorine plasma, the temperature is maintained in the range of 1200-2000 deg K to: a) allow any PuF6 (gas) that is formed to decompose back to PuF4 (solid), and b) to maintain stability of the UF6. Uranium (in the form of gaseous UF6) is easily extracted and separated from the plutonium (in the form of solid PuF4). The use of plasmas instead of high temperature reactors or flames mitigates the high temperature corrosive atmosphere and the production of PuF6 (as a final product). Use of plasmas provide faster reaction rates, greater control over the individual electron and ion temperatures, and allow the use of CF4 or NF3 as the fluorine sources instead of F2 or HF.

  19. Reduction of Worldwide Plutonium Inventories Using Conventional Reactors and Advanced Fuels: A Systems Study

    SciTech Connect

    Krakowski, R.A., Bathke, C.G.

    1997-12-31

    The potential for reducing plutonium inventories in the civilian nuclear fuel cycle through recycle in LWRs of a variety of mixed oxide forms is examined by means of a cost based plutonium flow systems model. This model emphasizes: (1) the minimization of separated plutonium; (2) the long term reduction of spent fuel plutonium; (3) the optimum utilization of uranium resources; and (4) the reduction of (relative) proliferation risks. This parametric systems study utilizes a globally aggregated, long term (approx. 100 years) nuclear energy model that interprets scenario consequences in terms of material inventories, energy costs, and relative proliferation risks associated with the civilian fuel cycle. The impact of introducing nonfertile fuels (NFF,e.g., plutonium oxide in an oxide matrix that contains no uranium) into conventional (LWR) reactors to reduce net plutonium generation, to increase plutonium burnup, and to reduce exo- reactor plutonium inventories also is examined.

  20. Modeling the Pyrochemical Reduction of Spent UO2 Fuel in a Pilot-Scale Reactor

    SciTech Connect

    Steven D. Herrmann; Michael F. Simpson

    2006-08-01

    A kinetic model has been derived for the reduction of oxide spent nuclear fuel in a radial flow reactor. In this reaction, lithium dissolved in molten LiCl reacts with UO2 and fission product oxides to form a porous, metallic product. As the reaction proceeds, the depth of the porous layer around the exterior of each fuel particle increases. The observed rate of reaction has been found to be only dependent upon the rate of diffusion of lithium across this layer, consistent with a classic shrinking core kinetic model. This shrinking core model has been extended to predict the behavior of a hypothetical, pilot-scale reactor for oxide reduction. The design of the pilot-scale reactor includes forced flow through baskets that contain the fuel particles. The results of the modeling indicate that this is an essential feature in order to minimize the time needed to achieve full conversion of the fuel.

  1. Analytical Dimensional Reduction of a Fuel Optimal Powered Descent Subproblem

    NASA Technical Reports Server (NTRS)

    Rea, Jeremy R.; Bishop, Robert H.

    2010-01-01

    Current renewed interest in exploration of the moon, Mars, and other planetary objects is driving technology development in many fields of space system design. In particular, there is a desire to land both robotic and human missions on the moon and elsewhere. The landing guidance system must be able to deliver the vehicle to a desired soft landing while meeting several constraints necessary for the safety of the vehicle. Due to performance limitations of current launch vehicles, it is desired to minimize the amount of fuel used. In addition, the landing site may change in real-time in order to avoid previously undetected hazards which become apparent during the landing maneuver. This complicated maneuver can be broken into simpler subproblems that bound the full problem. One such subproblem is to find a minimum-fuel landing solution that meets constraints on the initial state, final state, and bounded thrust acceleration magnitude. With the assumptions of constant gravity and negligible atmosphere, the form of the optimal steering law is known, and the equations of motion can be integrated analytically, resulting in a system of five equations in five unknowns. It is shown that this system of equations can be reduced analytically to two equations in two unknowns. With an additional assumption of constant thrust acceleration magnitude, this system can be reduced further to one equation in one unknown. It is shown that these unknowns can be bounded analytically. An algorithm is developed to quickly and reliably solve the resulting one-dimensional bounded search, and it is used as a real-time guidance applied to a lunar landing test case.

  2. Fuel oil cleaning as a risk reduction strategy for utility units firing residual fuel oils

    SciTech Connect

    Booth, R.B.

    1995-12-31

    The Clean Air Act Amendments of 1990 (CAAA) ushered in a new era in the regulatory battle to achieve the clean air goals of Congress and the Environmental Protection Agency (EPA). Title III of the CAAA addresses the new air toxic emissions program approach applicable to a wide range and variety of sources, including utility boilers firing residual fuel oils (RFO), while Title IX of the CAAA addresses the implementation of the pollution prevention program. Utilities which burn RFO may be interested in the concept of fuel cleaning as a means to reduce the emission of several fuel related toxics. Such a concept would clearly qualify as a pollution prevention technique. The concept of fuel cleaning has generated some interest with respect to the removal of a number of toxic and/or carcinogenic fuel bound metals. Fuel cleaning would shift the focus of the utilities from the need to employ flue gas treatment and removal technologies on large volumes of combustion exhaust gases, to fuel cleaning technologies applicable to a much smaller volume of fuel oil. The removal of fuel-bound metals prior to combustion would obviously lessen the emission of such metals and reduce the associated risk of such emissions to the surrounding population. This paper presents a very preliminary and general evaluation of the risks associated with RFO combustion for a baseline fuel case as well as a number of cases in which various metals are removed from the baseline oil. The risks are based on a conservative approach to both dispersion modeling and health risk impact assessment.

  3. Reduction of CO2 to C1 products and fuel

    USGS Publications Warehouse

    Mill, T.; Ross, D.

    2002-01-01

    Photochemical semiconductor processes readily reduced CO2 to a broad range of C1 products. However the intrinsic and solar efficiencies for the processes were low. Improved quantum efficiencies could be realized utilizing quantum-sized particles, but at the expense of using less of the visible solar spectrum. Conversely, semiconductors with small bandgaps used more of the visible solar spectrum at the expense of quantum efficiency. Thermal reduction of CO2 with Fe(II) was thermodynamically favored for forming many kinds of organic compounds and occurred readily with olivine and other Fe(II) minerals above 200??C to form higher alkanes and alkenes. No added hydrogen was required.

  4. Influences of vehicles’ fuel consumption and exhaust emissions on the trip cost without late arrival under car-following model

    NASA Astrophysics Data System (ADS)

    Tang, Tie-Qiao; Yu, Qiang

    2016-07-01

    In this paper, we use car-following model to explore the influences of the vehicle’s fuel consumption and exhaust emissions on each commuter’s trip cost without late arrival on one open road. Our results illustrate that considering the vehicle’s fuel cost and emission cost only enhances each commuter’s trip cost and the system’s total cost, but has no prominent impacts on his optimal time headway at the origin of each open road under the minimum total cost.

  5. Modeling of rotary cement kilns: Applications to reduction in energy consumption

    SciTech Connect

    Mujumdar, K.S.; Arora, A.; Ranade, V.V.

    2006-03-29

    We discuss and evaluate possible ways of reducing energy consumption in rotary cement kilns. A comprehensive one-dimensional model was developed to simulate complex processes occurring in rotary cement kilns. A modeling strategy comprising three submodels, viz. a model for simulating the variation of bed height in the kiln, a model for simulating reactions and heat transfer in the bed region, and a model for simulating coal combustion and heat transfer in the freeboard region, was developed. Melting and formation of coating within the kiln were accounted for. Combustion of coal in the freeboard region was modeled by accounting for devolatilization, finite-rate gas-phase combustion, and char reaction. The simulated results were validated with the available data from three industrial kilns. The model was then used to understand the influence of various design and operating parameters on kiln performance. Several ways of reducing energy consumption in kilns were then computationally investigated. The model was also used to propose and to evaluate a practical solution of using a secondary shell to reduce energy consumption in rotary cement kilns. Simulation results indicate that varying kiln operating variables, viz. solid flow rate or RPM, can result only in small changes in kiln energetics. Use of a secondary shell over the kiln and energy recovery by passing air through the annular gap between the two appears to be a promising way to achieve significant energy savings. The developed model and the presented results will be useful for enhancing the performance of rotary cement kilns.

  6. Emerging technology for the reduction of sulfur in FCC fuels

    SciTech Connect

    Wormsbecher, R.F.; Weatherbee, G.D.; Kim, G.; Dougan, T.J. )

    1993-01-01

    Passage of the Clean Air Act of 1990 and new regulations issued in California will set new limits on the sulfur content of gasoline. Because most of the sulfur in the gasoline pool comes from FCC naphtha, there is a strong incentive to reduce the sulfur content of this stream in the most cost efficient manner. This work introduces emerging catalytic technology for the direct reduction of the sulfur content of FCC gasolines, called the GSR[trademark] (Gasoline Sulfur Reduction) technology. Studies of this new technology were carried out using the Davison Circulating Riser pilot unit. The GSR technology is shown to reduce the sulfur in FCC naphtha by 15%, with two feedstocks. It is shown that this technology is selective to sulfur species in the middle of the gasoline boiling range, and converts these species to H[sub 2]S, while preserving most of the base catalyst selectivities. Various other catalytic scenarios for minimizing the gasoline sulfur content are also given.

  7. POTENTIAL OF GREENHOUSE GASES REDUCTION BY FUEL CROP CULTIVATION UTILIZING SEWAGE SLUDGE IN JAPAN

    NASA Astrophysics Data System (ADS)

    Honda, Ryo; Fukushi, Kensuke

    Potential of greenhouse gases (GHG) reduction was estimated and compared in six scenarios of fuel crop cultivation by utilizing sewage sludge in Japan. Bioethanol from corn and biodiesel fuel from soybean was selected as biofuel produced. When all the sludge discharged from sewage treatment plants in 18 major cities was utilized for soybean cultivation and subsequent biodiesel fuel production, produced biofuel corresponded to 4.0% of GHG emitted from sewage treatment in Japan. On the other hand, cultivation area for fuel crop cultivation was found to be the regulating factor. When fuel crop was cultivated only in abandoned agricultural fields, produced biofuel corresponded to 0.60% and 0.62%, respectively, in the case that corn and soybean was cultivated. Production of biodiesel fuel from soybean was estimated to have more net reduction potential than bioehanol production from corn when sludge production is limited, because required sewage sludge compost was 2.5-times larger in corn although reduction potential per crop area was 2-times larger in bioethanol production from corn.

  8. The Production, Value, and Reduction Responsibility of Carbon Emissions through Electricity Consumption of Manufacturing Industries in South Korea and Thailand

    NASA Astrophysics Data System (ADS)

    Kitikun, Medhawin

    This dissertation provides a new method of measuring efforts by manufacturing industries to reduce their emissions by curtailing electricity consumption. Employing comprehensive firm-level data from the National Manufacture Annual Surveys of South Korea and Thailand, I construct the measure from estimates of revenue functions by industry. The data consists of firms from more than 20 industries in each year from 1982 to 2005 for Korea and from 2001 to 2008 for Thailand. With a total of more than two million observations, I estimate revenue functions for each industry and year. Here, I use three inputs: number of employees(L), fixed asset stock(K), and electricity consumption(E) and two types of functional forms to represent each industry's revenue function. Second, under market competitive condition, I find that profit maximizing firms deviated their level of electricity usage in production from the profit-maximizing level during the time period for both countries, and I develop a theoretical framework to explain this behavior. Then, I tested the theory using my empirical models. Results support the notion of a hidden environmental value expressed by firms in the form of voluntary deviations from profit-maximizing levels of input demand. The measure used is the gap between the marginal revenue product of electricity and its price. This gap should increase with income, consistent with the Environmental Kuznets Curve literature. My current model provides considerable support for this proposition. Estimates indicate, in most industries, a negative relationship between per-capita income and emissions. In the final section of the dissertation, I consider the equitable distribution of emissions reduction burden under an international agreement such as the reduction effort, Kyoto Protocol. Both developed and developing countries have to cut their emissions to a specific reduction percentage target. Domestically, I present two extreme scenarios. In the first scenario

  9. Pilot-scale equipment development for lithium-based reduction of spent oxide fuel.

    SciTech Connect

    Herrmann, S. D.

    1998-04-24

    An integral function of the electrometallurgical conditioning of DOE spent nuclear fuel is the standardization of waste forms. Argonne National Laboratory (ANL) has developed and is presently demonstrating the electrometallurgical conditioning of sodium-bonded metal fuel from Experimental Breeder Reactor II, resulting in uranium, ceramic waste, and metal waste forms. Engineering studies are underway at ANL in support of pilot-scale equipment development, which would precondition irradiated oxide fuel and likewise demonstrate the application of electrometallurgical conditioning to such non-metallic fuels. This paper highlights the integration of proposed spent oxide fuel conditioning with existing electrometallurgical processes. Additionally, technical bases for engineering activities to support a scale up of an oxide reduction process are described.

  10. Modeling Heavy/Medium-Duty Fuel Consumption Based on Drive Cycle Properties

    SciTech Connect

    Wang, Lijuan; Duran, Adam; Gonder, Jeffrey; Kelly, Kenneth

    2015-10-13

    This paper presents multiple methods for predicting heavy/medium-duty vehicle fuel consumption based on driving cycle information. A polynomial model, a black box artificial neural net model, a polynomial neural network model, and a multivariate adaptive regression splines (MARS) model were developed and verified using data collected from chassis testing performed on a parcel delivery diesel truck operating over the Heavy Heavy-Duty Diesel Truck (HHDDT), City Suburban Heavy Vehicle Cycle (CSHVC), New York Composite Cycle (NYCC), and hydraulic hybrid vehicle (HHV) drive cycles. Each model was trained using one of four drive cycles as a training cycle and the other three as testing cycles. By comparing the training and testing results, a representative training cycle was chosen and used to further tune each method. HHDDT as the training cycle gave the best predictive results, because HHDDT contains a variety of drive characteristics, such as high speed, acceleration, idling, and deceleration. Among the four model approaches, MARS gave the best predictive performance, with an average absolute percent error of -1.84% over the four chassis dynamometer drive cycles. To further evaluate the accuracy of the predictive models, the approaches were first applied to real-world data. MARS outperformed the other three approaches, providing an average absolute percent error of -2.2% of four real-world road segments. The MARS model performance was then compared to HHDDT, CSHVC, NYCC, and HHV drive cycles with the performance from Future Automotive System Technology Simulator (FASTSim). The results indicated that the MARS method achieved a comparative predictive performance with FASTSim.

  11. Modeling studies of water consumption for transportation fuel options: Hawaii, US-48

    NASA Astrophysics Data System (ADS)

    King, C. W.; Webber, M. E.

    2011-12-01

    There are now major drivers to move from petroleum transportation: moving to low-carbon transport life cycles for climate change mitigation, fuel diversity to reduce reliance on imported oil, and economic concerns regarding the relatively high price of oil ( $100/barrel) and the resulting impact on discretionary income. Unfortunately many transportation fuel alternatives also have some environmental impacts, particularly with regard to water consumption and biodiversity. In this presentation we will discuss the water and energy sustainability struggle ongoing in Hawai'i on the island of Maui with a brief history and discussion of energy and water modeling scenarios. The vast majority of surface water on Maui is diverted via man-made ditches for irrigation on sugar cane plantations. Maui currently allocates between 250 and 300 million gallons per day (Mgal/d) of irrigation water for sugarcane cultivation each day, and it is likely that the island could support a biofuel-focused sugarcane plantation by shifting production focus from raw sugar to ethanol. However, future water availability is likely to be less than existing water availability because Maui is growing, more water is being reserved for environmental purposes, and precipitation levels are on decline for the past two decades and some expect this trend to continue. While Maui residents cannot control precipitation patterns, they can control the levels of increased requirements for instream flow in Maui's streams. The Hawaii State Commission on Water Resource Management (CWRM) sets instream flow standards, and choosing not to restore instream flow could have what many locals consider negative environmental and cultural impacts that must be weighed against the effects of reducing surface water availability for agriculture. Instream flow standards that reduce legal withdrawals for streams that supply irrigation water would reduce the amount of surface water available for biofuel crop irrigation. Environmental

  12. Hibernating myocardium retains metabolic and contractile reserve despite regional reductions in flow, function, and oxygen consumption at rest.

    PubMed

    Fallavollita, James A; Malm, Brian J; Canty, John M

    2003-01-10

    Hibernating myocardium, characterized by reductions in flow and function at rest, has limited contractile reserve in response to increases in external workload. We hypothesized that this attenuation of function reflects an adaptive downregulation that prevents the development of metabolic evidence of ischemia during stress. To test this hypothesis, pigs were chronically instrumented with a proximal left anterior descending artery stenosis for 3 months, resulting in severe anteroapical hypokinesis with reduced resting perfusion (0.78+/-0.05 versus 0.94+/-0.07 mL x min(-1)x g(-1) in remote, P<0.01; and 0.99+/-0.08 in controls, P<0.05). Open-chest studies confirmed resting dysfunction compared with normal controls (segment shortening 9.2+/-2.2% versus 23.5+/-1.1%, P<0.05). Resting myocardial oxygen consumption was reduced (63+/-3 versus 77+/-6 microL x g(-1) x min(-1) in controls, P<0.05), yet lactate consumption was normal. Although subendocardial perfusion failed to increase during graded, intravenous epinephrine infusion (n=8), peak segment shortening (to 17.3+/-3.1%, P<0.05) and oxygen consumption (to 90+/-6 microL x g(-1) x min(-1), P<0.01) increased from the depressed resting levels. There was no lactate production in hibernating myocardium, and lactate uptake increased during stress (0.7+/-0.1 to 1.2+/-0.1 micromol x g(-1) x min(-1), P<0.05). The absence of metabolic evidence of ischemia was also confirmed during atrial pacing to a rate of 120 bpm (n=8). Thus, despite reductions in function and oxygen consumption at rest, hibernating myocardium retains the ability to increase metabolism without the development of acute ischemia. This supports the hypothesis that the downregulation of oxygen consumption and function in hibernating myocardium is an adaptive response that prevents a supply-demand imbalance during submaximal increases in cardiac workload when coronary flow reserve is limited. PMID:12522120

  13. Water withdrawal and consumption reduction analysis for electrical energy generation system

    NASA Astrophysics Data System (ADS)

    Nouri, Narjes

    There is an increasing concern over shrinking water resources. Water use in the energy sector primarily occurs in electricity generation. Anticipating scarcer supplies, the value of water is undoubtedly on the rise and design, implementation, and utilization of water saving mechanisms in energy generation systems are becoming inevitable. Most power plants generate power by boiling water to produce steam to spin electricity-generating turbines. Large quantities of water are often used to cool the steam in these plants. As a consequence, most fossil-based power plants in addition to consuming water, impact the water resources by raising the temperature of water withdrawn for cooling. A comprehensive study is conducted in this thesis to analyze and quantify water withdrawals and consumption of various electricity generation sources such as coal, natural gas, renewable sources, etc. Electricity generation for the state of California is studied and presented as California is facing a serious drought problem affecting more than 30 million people. Integrated planning for the interleaved energy and water sectors is essential for both water and energy savings. A linear model is developed to minimize the water consumption while considering several limitations and restrictions. California has planned to shut down some of its hydro and nuclear plants due to environmental concerns. Studies have been performed for various electricity generation and water saving scenarios including no-hydro and no-nuclear plant and the results are presented. Modifications to proposed different scenarios have been applied and discussed to meet the practical and reliability constraints.

  14. THE WASTE REDUCTION (WAR) ALGORITHM: ENVIRONMENTAL IMPACTS, ENERGY CONSUMPTION, AND ENGINEERING ECONOMICS

    EPA Science Inventory

    A general theory known as the Waste Reduction (WAR) Algorithm has been developed to describe the flow and the generation of potential environmental impact through a chemical process. The theory defines indexes that characterize the generation and the output of potential environm...

  15. THE WASTE REDUCTION (WAR) ALGORITHM: ENVIRONMENTAL IMPACTS, ENERGY CONSUMPTION, AND ENGINEERING ECONOMICS

    EPA Science Inventory

    A general theory known as the WAste Reduction (WAR) algorithm has been developed to describe the flow and the generation of potential environmental impact through a chemical process. This theory defines potential environmental impact indexes that characterize the generation and t...

  16. Projections of motor vehicle growth, fuel consumption and CO{sub 2} emissions for the next thirty years in China.

    SciTech Connect

    He, D.; Wang, M.

    2000-12-12

    Since the early 1990s, China's motor vehicles have entered a period of fast growth resultant from the rapid economic expansion. As the largest developing country, the fast growth of China's motor vehicles will have tremendous effects on the world's automotive and fuel market and on global CO{sub 2} emissions. In this study, we projected Chinese vehicle stocks for different vehicle types on the provincial level. First, we reviewed the historical data of China's vehicle growth in the past 10 years and the correlations between vehicle growth and economic growth in China. Second, we investigated historical vehicle growth trends in selected developed countries over the past 50 or so years. Third, we established a vehicle growth scenario based on the historical trends in several developed nations. Fourth, we estimated fuel economy, annual mileage and other vehicle usage parameters for Chinese vehicles. Finally, we projected vehicle stocks and estimated motor fuel use and CO{sub 2} emissions in each Chinese province from 2000 to 2030. Our results show that China will continue the rapid vehicle growth, increase gasoline and diesel consumption and increased CO{sub 2} emissions in the next 30 years. We estimated that by year 2030, Chinese motor vehicle fuel consumption and CO{sub 2} emissions could reach the current US levels.

  17. ENERGY CONSUMPTION OF ENVIRONMENTAL CONTROLS: FOSSIL FUEL, STEAM ELECTRIC GENERATING INDUSTRY

    EPA Science Inventory

    The report addresses the energy requirements for environmental control in the fossil fuel, steam electric industry. These requirements arise through a number of mechanisms, including: direct fuel or electricity requirements for operating pollution control equipment, including pro...

  18. Real-world emissions and fuel consumption of diesel buses and trucks in Macao: From on-road measurement to policy implications

    NASA Astrophysics Data System (ADS)

    Wu, Xiaomeng; Zhang, Shaojun; Wu, Ye; Li, Zhenhua; Zhou, Yu; Fu, Lixin; Hao, Jiming

    2015-11-01

    A total of 13 diesel buses and 12 diesel trucks in Macao were tested using portable emission measurement systems (PEMS) including a SEMTECH-DS for gaseous emissions and a SEMTECH-PPMD for PM2.5. The average emission rates of gaseous pollutants and CO2 are developed with the operating mode defined by the instantaneous vehicle specific power (VSP) and vehicle speed. Both distance-based and fuel mass-based emission factors for gaseous pollutants (e.g., CO, THC and NOX) are further estimated under typical driving conditions. The average distance-based NOX emission of heavy-duty buses (HDBs) is higher than 13 g km-1. Considering the unfavorable conditions for selective reductions catalyst (SCR) systems, such as low-speed driving conditions, more effective technology options (e.g., dedicated natural gas buses and electric buses) should be considered by policy makers in Macao. We identified strong effects of the vehicle size, engine displacement and driving conditions on real-world CO2 emission factors and fuel consumption for diesel vehicles. Therefore, detailed profiles regarding vehicle specifications can reduce the uncertainty in their fleet-average on-road fuel consumption. In addition, strong correlations between relative emission factors and driving conditions indicated by the average speed of generated micro-trips are identified based on a micro-trip method. For example, distance-based emission factors of HDBs will increase by 39% for CO, 29% for THC, 43% for NOX and 26% for CO2 when the average speed decreases from 30 km h-1 to 20 km h-1. The mitigation of on-road emissions from diesel buses and trucks by improving traffic conditions through effective traffic and economic management measures is therefore required. This study demonstrates the important role of PEMS in understanding vehicle emissions and mitigation strategies from science to policy perspectives.

  19. Mechanism reduction for multicomponent surrogates: A case study using toluene reference fuels

    SciTech Connect

    Niemeyer, Kyle E.; Sung, Chih-Jen

    2014-11-01

    Strategies and recommendations for performing skeletal reductions of multicomponent surrogate fuels are presented, through the generation and validation of skeletal mechanisms for a three-component toluene reference fuel. Using the directed relation graph with error propagation and sensitivity analysis method followed by a further unimportant reaction elimination stage, skeletal mechanisms valid over comprehensive and high-temperature ranges of conditions were developed at varying levels of detail. These skeletal mechanisms were generated based on autoignition simulations, and validation using ignition delay predictions showed good agreement with the detailed mechanism in the target range of conditions. When validated using phenomena other than autoignition, such as perfectly stirred reactor and laminar flame propagation, tight error control or more restrictions on the reduction during the sensitivity analysis stage were needed to ensure good agreement. In addition, tight error limits were needed for close prediction of ignition delay when varying the mixture composition away from that used for the reduction. In homogeneous compression-ignition engine simulations, the skeletal mechanisms closely matched the point of ignition and accurately predicted species profiles for lean to stoichiometric conditions. Furthermore, the efficacy of generating a multicomponent skeletal mechanism was compared to combining skeletal mechanisms produced separately for neat fuel components; using the same error limits, the latter resulted in a larger skeletal mechanism size that also lacked important cross reactions between fuel components. Based on the present results, general guidelines for reducing detailed mechanisms for multicomponent fuels are discussed.

  20. Mechanism reduction for multicomponent surrogates: A case study using toluene reference fuels

    DOE PAGESBeta

    Niemeyer, Kyle E.; Sung, Chih-Jen

    2014-11-01

    Strategies and recommendations for performing skeletal reductions of multicomponent surrogate fuels are presented, through the generation and validation of skeletal mechanisms for a three-component toluene reference fuel. Using the directed relation graph with error propagation and sensitivity analysis method followed by a further unimportant reaction elimination stage, skeletal mechanisms valid over comprehensive and high-temperature ranges of conditions were developed at varying levels of detail. These skeletal mechanisms were generated based on autoignition simulations, and validation using ignition delay predictions showed good agreement with the detailed mechanism in the target range of conditions. When validated using phenomena other than autoignition, suchmore » as perfectly stirred reactor and laminar flame propagation, tight error control or more restrictions on the reduction during the sensitivity analysis stage were needed to ensure good agreement. In addition, tight error limits were needed for close prediction of ignition delay when varying the mixture composition away from that used for the reduction. In homogeneous compression-ignition engine simulations, the skeletal mechanisms closely matched the point of ignition and accurately predicted species profiles for lean to stoichiometric conditions. Furthermore, the efficacy of generating a multicomponent skeletal mechanism was compared to combining skeletal mechanisms produced separately for neat fuel components; using the same error limits, the latter resulted in a larger skeletal mechanism size that also lacked important cross reactions between fuel components. Based on the present results, general guidelines for reducing detailed mechanisms for multicomponent fuels are discussed.« less

  1. Basic laws of the processes and the principle of minimum energy consumption during pneumatic transport and distribution of pulverized fuel in direct pulverized fuel preparation systems

    NASA Astrophysics Data System (ADS)

    Leykin, V. Z.

    2015-08-01

    The paper presents analysis of the basic laws and a calculation-based investigation of processes related to the low-concentration pneumatic transport and the distribution of finely dispersed pulverized fuel in direct pulverized fuel preparation systems of boiler units. Based on the principle of the minimum energy consumption, it is shown that, at high (standard) velocities of the turbulent gas flow—of 25-30 m/s, which is by 1.5-2 times higher than the critical speeds—the finely dispersed pulverized fuel can be transported simultaneously in the form of a low-concentration flow in pipelines and a concentrated, to 30% of the flow rate, thin layer on the pipeline walls with the height of the layer equal to 0.02-0.04 of the pipe radius. Consideration of this phenomenon is of great significance in terms of securing the efficient operation of pulverized fuel distribution units. The basic characteristics of the process have been determined and validated by test bench investigations using both model systems and pulverized fuel distribution systems of a number of power-generating units. The obtained results underlie a methodological approach to developing high-efficiency adjustable pulverized fuel distribution units. Also, results of industrial testing are presented that confirm the results of the analysis and of experimental studies.

  2. Quantitative Estimate of the Relation Between Rolling Resistance on Fuel Consumption of Class 8 Tractor Trailers Using Both New and Retreaded Tires (SAE Paper 2014-01-2425)

    EPA Science Inventory

    Road tests of class 8 tractor trailers were conducted by the US Environmental Protection Agency on new and retreaded tires of varying rolling resistance in order to provide estimates of the quantitative relationship between rolling resistance and fuel consumption.

  3. Alternative Fuel Vehicle Adoption Increases Fleet Gasoline Consumption and Greenhouse Gas Emissions under United States Corporate Average Fuel Economy Policy and Greenhouse Gas Emissions Standards.

    PubMed

    Jenn, Alan; Azevedo, Inês M L; Michalek, Jeremy J

    2016-03-01

    The United States Corporate Average Fuel Economy (CAFE) standards and Greenhouse Gas (GHG) Emission standards are designed to reduce petroleum consumption and GHG emissions from light-duty passenger vehicles. They do so by requiring automakers to meet aggregate criteria for fleet fuel efficiency and carbon dioxide (CO2) emission rates. Several incentives for manufacturers to sell alternative fuel vehicles (AFVs) have been introduced in recent updates of CAFE/GHG policy for vehicles sold from 2012 through 2025 to help encourage a fleet technology transition. These incentives allow automakers that sell AFVs to meet less-stringent fleet efficiency targets, resulting in increased fleet-wide gasoline consumption and emissions. We derive a closed-form expression to quantify these effects. We find that each time an AFV is sold in place of a conventional vehicle, fleet emissions increase by 0 to 60 t of CO2 and gasoline consumption increases by 0 to 7000 gallons (26,000 L), depending on the AFV and year of sale. Using projections for vehicles sold from 2012 to 2025 from the Energy Information Administration, we estimate that the CAFE/GHG AFV incentives lead to a cumulative increase of 30 to 70 million metric tons of CO2 and 3 to 8 billion gallons (11 to 30 billion liters) of gasoline consumed over the vehicles' lifetimes - the largest share of which is due to legacy GHG flex-fuel vehicle credits that expire in 2016. These effects may be 30-40% larger in practice than we estimate here due to optimistic laboratory vehicle efficiency tests used in policy compliance calculations. PMID:26867100

  4. Noise and Fuel Burn Reduction Potential of an Innovative Subsonic Transport Configuration

    NASA Technical Reports Server (NTRS)

    Guo, Yueping; Nickol, Craig L.; Thomas, Russell H.

    2014-01-01

    A study is presented for the noise and fuel burn reduction potential of an innovative double deck concept aircraft with two three-shaft direct-drive turbofan engines. The engines are mounted from the fuselage so that the engine inlet is over the main wing. It is shown that such an aircraft can achieve a cumulative Effective Perceived Noise Level (EPNL) about 28 dB below the current aircraft noise regulations of Stage 4. The combination of high bypass ratio engines and advanced wing design with laminar flow control technologies provide fuel burn reduction and low noise levels simultaneously. For example, the fuselage mounted engine position provides more than 4 EPNLdB of noise reduction by shielding the inlet radiated noise. To identify the potential effect of noise reduction technologies on this concept, parametric studies are presented to reveal the system level benefits of various emerging noise reduction concepts, for both engine and airframe noise reduction. These concepts are discussed both individually to show their respective incremental noise reduction potential and collectively to assess their aggregate effects on the total noise. Through these concepts approximately about 8 dB of additional noise reduction is possible, bringing the cumulative noise level of this aircraft to 36 EPNLdB below Stage 4, if the entire suite of noise reduction technologies would mature to practical application. In a final step, an estimate is made for this same aircraft concept but with higher bypass ratio, geared, turbofan engines. With this geared turbofan propulsion system, the noise is estimated to reach as low as 40-42 dB below Stage 4 with a fuel burn reduction of 43-47% below the 2005 best-in-class aircraft baseline. While just short of the NASA N+2 goals of 42 dB and 50% fuel burn reduction, for a 2025 in service timeframe, this assessment shows that this innovative concept warrants refined study. Furthermore, this design appears to be a viable potential future passenger

  5. R&D on fuel cells in Japan and possible contributions of fuel cells to the Global Reduction of CO{sub 2} emissions

    SciTech Connect

    Takenaka, Hiroyasu

    1993-12-31

    Fuel cells can generate electricity equivalent to 40-60% of the energy contained In the fuel consumed, and an overall efficiency as high as 80% is not impossible to achieve through utilization of the exhaust heat. In addition, emissions of pollutants such as NOx and SOx from fuel cells are low. Since various reformed gases derived from natural gas, methanol and coal can be used as fuel for fuel cells, the wide range of applications for fuel cells is expected to contribute to the reduction of petroleum dependence in Japan.

  6. A fuel cycle framework for evaluating greenhouse gas emission reduction technology

    SciTech Connect

    Ashton, W.B.; Barns, D.W. ); Bradley, R.A. . Office of Environmental Analysis)

    1990-05-01

    Energy-related greenhouse gas (GHG) emissions arise from a number of fossil fuels, processes and equipment types throughout the full cycle from primary fuel production to end-use. Many technology alternatives are available for reducing emissions based on efficiency improvements, fuel switching to low-emission fuels, GHG removal, and changes in end-use demand. To conduct systematic analysis of how new technologies can be used to alter current emission levels, a conceptual framework helps develop a comprehensive picture of both the primary and secondary impacts of a new technology. This paper describes a broad generic fuel cycle framework which is useful for this purpose. The framework is used for cataloging emission source technologies and for evaluating technology solutions to reduce GHG emissions. It is important to evaluate fuel mix tradeoffs when investigating various technology strategies for emission reductions. For instance, while substituting natural gas for coal or oil in end-use applications to reduce CO{sub 2} emissions, natural gas emissions of methane in the production phase of the fuel cycle may increase. Example uses of the framework are given.

  7. 75 FR 63404 - Fossil Fuel-Generated Energy Consumption Reduction for New Federal Buildings and Major...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-15

    ... 135 77 39 0 Food Service 404 182 141 81 40 0 Health Care (Inpatient) 313 141 109 63 31 0 Health Care... the Federal Energy Management Program's Web site http://www1.eere.energy.gov/femp/regulations/notices... Room of the Federal Energy Management Program), 1000 Independence Avenue, SW., Washington, DC,...

  8. A STUDY OF THE DISCREPANCY BETWEEN FEDERAL AND STATE MEASUREMENTS OF ON-HIGHWAY FUEL CONSUMPTION

    SciTech Connect

    Hwang, HL

    2003-08-11

    Annual highway fuel taxes are collected by the Treasury Department and placed in the Highway Trust Fund (HTF). There is, however, no direct connection between the taxes collected by the Treasury Department and the gallons of on-highway fuel use, which can lead to a discrepancy between these totals. This study was conducted to determine how much of a discrepancy exists between the total fuel usages estimated based on highway revenue funds as reported by the Treasury Department and the total fuel usages used in the apportionment of the HTF to the States. The analysis was conducted using data from Highway Statistics Tables MF-27 and FE-9 for the years 1991-2001. It was found that the overall discrepancy is relatively small, mostly within 5% difference. The amount of the discrepancy varies from year to year and varies among the three fuel types (gasoline, gasohol, special fuels). Several potential explanations for these discrepancies were identified, including issues on data, tax measurement, gallon measurement, HTF receipts, and timing. Data anomalies caused by outside forces, such as deferment of tax payments from one fiscal year to the next, can skew fuel tax data. Fuel tax evasion can lead to differences between actual fuel use and fuel taxes collected. Furthermore, differences in data collection and reporting among States can impact fuel use data. Refunds, credits, and transfers from the HTF can impact the total fuel tax receipt data. Timing issues, such as calendar year vs. fiscal year, can also cause some discrepancy between the two data sources.

  9. Geomicrobiological linkages between short-chain alkane consumption and sulfate reduction rates in seep sediments

    PubMed Central

    Bose, Arpita; Rogers, Daniel R.; Adams, Melissa M.; Joye, Samantha B.; Girguis, Peter R.

    2013-01-01

    Marine hydrocarbon seeps are ecosystems that are rich in methane, and, in some cases, short-chain (C2–C5) and longer alkanes. C2–C4 alkanes such as ethane, propane, and butane can be significant components of seeping fluids. Some sulfate-reducing microbes oxidize short-chain alkanes anaerobically, and may play an important role in both the competition for sulfate and the local carbon budget. To better understand the anaerobic oxidation of short-chain n-alkanes coupled with sulfate-reduction, hydrocarbon-rich sediments from the Gulf of Mexico (GoM) were amended with artificial, sulfate-replete seawater and one of four n-alkanes (C1–C4) then incubated under strict anaerobic conditions. Measured rates of alkane oxidation and sulfate reduction closely follow stoichiometric predictions that assume the complete oxidation of alkanes to CO2 (though other sinks for alkane carbon likely exist). Changes in the δ13C of all the alkanes in the reactors show enrichment over the course of the incubation, with the C3 and C4 incubations showing the greatest enrichment (4.4 and 4.5‰, respectively). The concurrent depletion in the δ13C of dissolved inorganic carbon (DIC) implies a transfer of carbon from the alkane to the DIC pool (−3.5 and −6.7‰ for C3 and C4 incubations, respectively). Microbial community analyses reveal that certain members of the class Deltaproteobacteria are selectively enriched as the incubations degrade C1–C4 alkanes. Phylogenetic analyses indicate that distinct phylotypes are enriched in the ethane reactors, while phylotypes in the propane and butane reactors align with previously identified C3–C4 alkane-oxidizing sulfate-reducers. These data further constrain the potential influence of alkane oxidation on sulfate reduction rates (SRRs) in cold hydrocarbon-rich sediments, provide insight into their contribution to local carbon cycling, and illustrate the extent to which short-chain alkanes can serve as electron donors and govern microbial

  10. Fuel reduction and coarse woody debris dynamics with early season and late season prescribed fire in a Sierra Nevada mixed conifer forest

    USGS Publications Warehouse

    Knapp, E.E.; Keeley, J.E.; Ballenger, E.A.; Brennan, T.J.

    2005-01-01

    Fire exclusion has led to an unnatural accumulation and greater spatial continuity of organic material on the ground in many forests. This material serves both as potential fuel for forest fires and habitat for a large array of forest species. Managers must balance fuel reduction to reduce wildfire hazard with fuel retention targets to maintain other forest functions. This study reports fuel consumption and changes to coarse woody debris attributes with prescribed burns ignited under different fuel moisture conditions. Replicated early season burn, late season burn, and unburned control plots were established in old-growth mixed conifer forest in Sequoia National Park that had not experienced fire for more than 120 years. Early season burns were ignited during June 2002 when fuels were relatively moist, and late season burns were ignited during September/October 2001 when fuels were dry. Fuel loading and coarse woody debris abundance, cover, volume, and mass were evaluated prior to and after the burns. While both types of burns reduced fuel loading, early season burns consumed significantly less of the total dead and down organic matter than late season burns (67% versus 88%). This difference in fuel consumption between burning treatments was significant for most all woody fuel components evaluated, plus the litter and duff layers. Many logs were not entirely consumed - therefore the number of logs was not significantly changed by fire - but burning did reduce log length, cover, volume, and mass. Log cover, volume, and mass were reduced to a lesser extent by early season burns than late season burns, as a result of higher wood moisture levels. Early season burns also spread over less of the ground surface within the burn perimeter (73%) than late season burns (88%), and were significantly patchier. Organic material remaining after a fire can dam sediments and reduce erosion, while unburned patches may help mitigate the impact of fire on fire-sensitive species by

  11. Hybrid-Electric Passenger Car Carbon Dioxide and Fuel Consumption Benefits Based on Real-World Driving.

    PubMed

    Holmén, Britt A; Sentoff, Karen M

    2015-08-18

    Hybrid-electric vehicles (HEVs) have lower fuel consumption and carbon dioxide (CO2) emissions than conventional vehicles (CVs), on average, based on laboratory tests, but there is a paucity of real-world, on-road HEV emissions and performance data needed to assess energy use and emissions associated with real-world driving, including the effects of road grade. This need is especially great as the electrification of the passenger vehicle fleet (from HEVs to PHEVs to BEVs) increases in response to climate and energy concerns. We compared tailpipe CO2 emissions and fuel consumption of an HEV passenger car to a CV of the same make and model during real-world, on-the-road network driving to quantify the in-use benefit of one popular full HEV technology. Using vehicle specific power (VSP) assignments that account for measured road grade, the mean CV/HEV ratios of CO2 tailpipe emissions or fuel consumption defined the corresponding HEV "benefit" factor for each VSP class (1 kW/ton resolution). Averaging over all VSP classes for driving in all seasons, including temperatures from -13 to +35 °C in relatively steep (-13.2 to +11.5% grade), hilly terrain, mean (±SD) CO2 emission benefit factors were 4.5 ± 3.6, 2.5 ± 1.7, and 1.4 ± 0.5 for city, exurban/suburban arterial and highway driving, respectively. Benefit factor magnitude corresponded to the frequency of electric-drive-only (EDO) operation, which was modeled as a logarithmic function of VSP. A combined model explained 95% of the variance in HEV benefit for city, 75% for arterial and 57% for highway driving. Benefit factors consistently exceeded 2 for VSP classes with greater than 50% EDO (i.e., only city and arterial driving). The reported HEV benefits account for real-world road grade that is often neglected in regulatory emissions and fuel economy tests. Fuel use HEV benefit factors were 1.3 and 2 for the regulatory highway (HWFET) and city (FTP) cycles, respectively, 18% and 31% higher than the EPA adjusted

  12. Substrate consumption and excess sludge reduction of activated sludge in the presence of uncouplers: a modeling approach.

    PubMed

    Xie, Wen-Ming; Ni, Bing-Jie; Sheng, Guo-Ping; Yu, Han-Qing; Yang, Min

    2010-02-01

    A mathematical model with a consideration of energy spilling is developed to describe the activated sludge in the presence of different levels of metabolic uncouplers. The consumption of substrate and oxygen via energy spilling process is modeled with a Monod term, which is dependent on substrate and inhibitor. The sensitivity of the developed model is analyzed. Three parameters, maximum specific growth rate (micro(max)), energy spilling coefficient (q(max)), and sludge yield coefficient (Y(H)) are estimated with experimental data of different studies. The values of micro(max), q(max), and Y(H) are found to be 6.72 day(-1), 5.52 day(-1), and 0.60 mg COD mg(-1) COD for 2, 4-dinitrophenol and 7.20 day(-1), 1.58 day(-1), and 0.62 mg COD mg(-1) COD for 2, 4-dichlorophenol. Substrate degradation and sludge yield could be predicted with this model. The activated sludge process in the presence of uncouplers that is described more reasonably by the new model with a consideration of energy spilling. The effects of uncouplers on substrate consumption inhibition and excess sludge reduction in activated sludge are quantified with this model. PMID:19898844

  13. "Just Advil": Harm reduction and identity construction in the consumption of over-the-counter medication for chronic pain.

    PubMed

    Eaves, Emery R

    2015-12-01

    Direct-to-consumer marketing has sparked ongoing debate concerning whether ads empower consumers to be agents of their own care or shift greater control to the pharmaceutical industry. Ads for over-the-counter (OTC) medications in particular portend to offer simple, harmless solutions for meeting the demands of social life. Rather than join the longstanding debate between consumer agency and social control in pharmaceutical advertising, I approach self-medication with over-the-counter (OTC) analgesics using Harm Reduction as a framework. From this perspective, consumption of OTC analgesics by chronic pain sufferers is a means of seeking some level of relief while also avoiding the stigma associated with prescription pain medication. Qualitative methods are used to analyze data from two sources: (1) semi-structured qualitative interviews with 95 participants in a trial examining the effectiveness of Traditional Chinese Medicine for Temporomandibular Disorders (TMD) from 2006 to 2011 in Tucson, AZ and Portland, OR; and (2) print, online, and television advertisements for three major brands of OTC pain medication. Participants described their use of OTC medications as minimal, responsible, and justified by the severity of their pain. OTC medication advertising, while ostensibly ambiguous and targeting all forms of pain, effectively lends support to the consumption of these medications as part of the self-projects of chronic pain sufferers, allowing them to reconcile conflicting demands for pain relief while being stoic and maintaining a positive moral identity. Describing OTC medication as "just over-the-counter" or "not real pain medication," sufferers engage in ideological harm reduction, distinguishing themselves from "those people who like taking pain medication" while still seeking relief. Justifying one's use of OTC medication as minimal and "normal," regardless of intake, avoids association with the addictive potential of prescription pain medications and

  14. Fuel Consumption and Fire Emissions Estimates in Siberia: Impact of Vegetation Types, Meteorological Conditions, Forestry Practices and Fire Regimes

    NASA Astrophysics Data System (ADS)

    Kukavskaya, Elena; Conard, Susan; Ivanova, Galina; Buryak, Ludmila; Soja, Amber; Zhila, Sergey

    2015-04-01

    Boreal forests play a crucial role in carbon budgets with Siberian carbon fluxes and pools making a major contribution to the regional and global carbon cycle. Wildfire is the main ecological disturbance in Siberia that leads to changes in forest species composition and structure and in carbon storage, as well as direct emissions of greenhouse gases and aerosols to the atmosphere. At present, the global scientific community is highly interested in quantitative and accurate estimates of fire emissions. Little research on wildland fuel consumption and carbon emission estimates has been carried out in Russia until recently. From 2000 to 2007 we conducted a series of experimental fires of varying fireline intensity in light-coniferous forest of central Siberia to obtain quantitative and qualitative data on fire behavior and carbon emissions due to fires of known behavior. From 2009 to 2013 we examined a number of burned logged areas to assess the potential impact of forest practices on fire emissions. In 2013-2014 burned areas in dark-coniferous and deciduous forests were examined to determine fuel consumption and carbon emissions. We have combined and analyzed the scarce data available in the literature with data obtained in the course of our long-term research to determine the impact of various factors on fuel consumption and to develop models of carbon emissions for different ecosystems of Siberia. Carbon emissions varied drastically (from 0.5 to 40.9 tC/ha) as a function of vegetation type, weather conditions, anthropogenic effects and fire behavior characteristics and periodicity. Our study provides a basis for better understanding of the feedbacks between wildland fire emissions and changing anthropogenic disturbance patterns and climate. The data obtained could be used by air quality agencies to calculate local emissions and by managers to develop strategies to mitigate negative smoke impacts on the environmentand human health.

  15. Fuel consumption and fire emissions estimates using Fire Radiative Power, burned area and statistical modelling on the fire event scale

    NASA Astrophysics Data System (ADS)

    Ruecker, Gernot; Leimbach, David; Guenther, Felix; Barradas, Carol; Hoffmann, Anja

    2016-04-01

    Fire Radiative Power (FRP) retrieved by infrared sensors, such as flown on several polar orbiting and geostationary satellites, has been shown to be proportional to fuel consumption rates in vegetation fires, and hence the total radiative energy released by a fire (Fire Radiative Energy, FRE) is proportional to the total amount of biomass burned. However, due to the sparse temporal coverage of polar orbiting and the coarse spatial resolution of geostationary sensors, it is difficult to estimate fuel consumption for single fire events. Here we explore an approach for estimating FRE through temporal integration of MODIS FRP retrievals over MODIS-derived burned areas. Temporal integration is aided by statistical modelling to estimate missing observations using a generalized additive model (GAM) and taking advantage of additional information such as land cover and a global dataset of the Canadian Fire Weather Index (FWI), as well as diurnal and annual FRP fluctuation patterns. Based on results from study areas located in savannah regions of Southern and Eastern Africa and Brazil, we compare this method to estimates based on simple temporal integration of FRP retrievals over the fire lifetime, and estimate the potential variability of FRP integration results across a range of fire sizes. We compare FRE-based fuel consumption against a database of field experiments in similar landscapes. Results show that for larger fires, this method yields realistic estimates and is more robust when only a small number of observations is available than the simple temporal integration. Finally, we offer an outlook on the integration of data from other satellites, specifically FireBird, S-NPP VIIRS and Sentinel-3, as well as on using higher resolution burned area data sets derived from Landsat and similar sensors.

  16. Photochemical reduction of CO{sub 2} to fuels and chemicals

    SciTech Connect

    DuBois, D.; Eisenberg, R.; Fujita, E.

    1996-09-01

    Photochemical reduction of CO{sub 2} represents a potentially useful approach to developing a sustainable source of carbon-based chemicals, fuels, and materials. In this report the present status of photochemical CO{sub 2} reduction is assessed, areas that need to be better understood for advancement are identified, and approaches to overcoming barriers are suggested. Because of the interdisciplinary nature of this field, assessments of three closely interrelated areas are given including integrated photochemical systems for catalytic CO{sub 2} reduction, thermal catalytic CO{sub 2} reactions, and electrochemical CO{sub 2} reduction. The report concludes with a summary and assessment of potential impacts of this area on chemical and energy technologies.

  17. Reduction of Helicopter BVI Noise, Vibration, and Power Consumption Through Individual Blade Control

    NASA Technical Reports Server (NTRS)

    Jacklin, Stephen A.; Blaas, Achim; Teves, Dietrich; Kube, Roland; Warmbrodt, William (Technical Monitor)

    1994-01-01

    A wind tunnel test was conducted with a full-scale BO 105 helicopter rotor to evaluate the potential of open-loop individual blade control (IBC) to improve rotor performance, to reduce blade vortex interaction (BVI) noise, and to alleviate helicopter vibrations. The wind tunnel test was an international collaborative effort between NASA/U.S. Army AFDD, ZF Luftfahrttechnik, Eurocopter Deutschland, and the German Aerospace Laboratory (DLR) and was conducted under the auspices of the U.S./German MOU on Rotorcraft Aeromechanics. In this test the normal blade pitch links of the rotor were replaced by servo-actuators so that the pitch of each blade could be controlled independently of the other blades. The specially designed servoactuators and IBC control system were designed and manufactured by ZF Luftfahrttechnik, GmbH. The wind tunnel test was conducted in the 40- by 80-Foot Wind Tunnel at the NASA Ames Research Center. An extensive amount of measurement information was acquired for each IBC data point. These data include rotor performance, static and dynamic hub forces and moments, rotor loads, control loads, inboard and outboard blade pitch motion, and BVI noise data. The data indicated very significant (80 percent) simultaneous reductions in both BVI noise and hub vibrations could be obtained using multi-harmonic input at the critical descent (terminal approach) condition. The data also showed that performance improvements of up to 7 percent could be obtained using 2P input at high-speed forward flight conditions.

  18. Development of an energy consumption and cost data base for fuel cell total energy systems and conventional building energy systems

    NASA Astrophysics Data System (ADS)

    Pine, G. D.; Christian, J. E.; Mixon, W. R.; Jackson, W. L.

    1980-07-01

    The procedures and data sources used to develop an energy consumption and system cost data base for use in predicting the market penetration of phosphoric acid fuel cell total energy systems in the nonindustrial building market are described. A computer program was used to simulate the hourly energy requirements of six types of buildings; office buildings; retail stores; hotels and motels; schools; hospitals; and multifamily residences. The simulations were done by using hourly weather tapes for one city in each of the ten Department of Energy administrative regions. Two types of building construction were considered, one for existing buildings and one for new buildings. A fuel cell system combined with electrically driven heat pumps and one combined with a gas boiler and an electrically driven chiller were compared with similar conventional systems. The methods of system simulation, component sizing, and system cost estimation are described for each system.

  19. Influence of fuel sulfur on the selective reduction of NO by NH/sub 3/

    SciTech Connect

    Lucas, D.; Brown, N.J.

    1981-01-01

    More intensive regulations of the emissions of nitrogen oxides from stationary combustion sources have prompted the innovation and characterization of new control technologies suitable for applications in utilities. One of the more recent and attractive abatement technologies is the Thermal DeNO/sub x/ process which has been described by Lyon and Longwell. This process removes NO by selectively reducing it with NH/sub 3/ added to the post-combustion gases containing excess oxygen. This process is thus independent of the NO formation mechanism and makes no distinction between thermal and fuel NO. The present study is concerned with characterizing the selective reduction process for light distillate oil fuel admixed with variable amounts of pyridene and thiophene in a laboratory scale combustion tunnel under a variety of experimental conditions. This paper reports on those aspects of the study concerned with the investigation of possible synergistic effects between the sulfur and selective reduction chemistry.

  20. Universal fuel basket for use with an improved oxide reduction vessel and electrorefiner vessel

    DOEpatents

    Herrmann, Steven D.; Mariani, Robert D.

    2002-01-01

    A basket, for use in the reduction of UO.sub.2 to uranium metal and in the electrorefining of uranium metal, having a continuous annulus between inner and outer perforated cylindrical walls, with a screen adjacent to each wall. A substantially solid bottom and top plate enclose the continuous annulus defining a fuel bed. A plurality of scrapers are mounted adjacent to the outer wall extending longitudinally thereof, and there is a mechanism enabling the basket to be transported remotely.

  1. Selective catalytic reduction operation with heavy fuel oil: NOx, NH3, and particle emissions.

    PubMed

    Lehtoranta, Kati; Vesala, Hannu; Koponen, Päivi; Korhonen, Satu

    2015-04-01

    To meet stringent NOx emission limits, selective catalytic reduction (SCR) is increasingly utilized in ships, likely also in combination with low-priced higher sulfur level fuels. In this study, the performance of SCR was studied by utilizing NOx, NH3, and particle measurements. Urea decomposition was studied with ammonia and isocyanic acid measurements and was found to be more effective with heavy fuel oil (HFO) than with light fuel oil. This is suggested to be explained by the metals found in HFO contributing to metal oxide particles catalyzing the hydrolysis reaction prior to SCR. At the exhaust temperature of 340 °C NOx reduction was 85-90%, while at lower temperatures the efficiency decreased. By increasing the catalyst loading, the low temperature behavior of the SCR was enhanced. The drawback of this, however, was the tendency of particle emissions (sulfate) to increase at higher temperatures with higher loaded catalysts. The particle size distribution results showed high amounts of nanoparticles (in 25-30 nm size), the formation of which SCR either increased or decreased. The findings of this work provide a better understanding of the usage of SCR in combination with a higher sulfur level fuel and also of ship particle emissions, which are a growing concern. PMID:25780953

  2. Quantifying the fuel use and greenhouse gas reduction potential of electric and hybrid vehicles.

    SciTech Connect

    Singh, M.; Wang, M.; Hazard, N.; Lewis, G.; Energy Systems; Northeast Sustainable Energy Association; Univ. of Michigan

    2000-01-01

    Since 1989, the Northeast Sustainable Energy Association (NESEA) has organized the American Tour de Sol in which a wide variety of participants operate electric vehicles (EVs) and hybrid electric vehicles (HEVs) for several hundred miles under various roadway conditions (e.g., city center and highway). The event offers a unique opportunity to collect on-the-road energy efficiency data for these EVs and HEVs as well as comparable gasoline-fueled conventional vehicles (CVs) that are driven under the same conditions. NESEA and Argonne National Laboratory (ANL) collaborated on collecting and analyzing vehicle efficiency data during the 1998 and 1999 NESEA American Tour de Sols. Using a transportation fuel-cycle model developed at ANL with data collected on vehicle fuel economy from the two events as well as electric generation mix data from the utilities that provided the electricity to charge the EVs on the two Tours, we estimated full fuel-cycle energy use and GHG emissions of EVs and CVs. This paper presents the data, methodology, and results of this study, including the full fuel-cycle energy use and GHG emission reduction potential of the EVs operating on the Tour.

  3. Global Threat Reduction Initiative Fuel-Thermo-Physical Characterization Project Quality Assurance Plan

    SciTech Connect

    Pereira, Mario M.; Slonecker, Bruce D.

    2012-06-01

    The charter of the Fuel Thermo-Physical Characterization Project is to ready Pacific Northwest National Laboratory (PNNL) facilities and processes for the receipt of unirradiated and irradiated low enriched uranium (LEU) molybdenum (U-Mo) fuel element samples, and to perform analysis to support the Global Threat Reduction Initiative conversion program. PNNL’s support for the program will include the establishment of post-irradiation examination processes, including thermo-physical properties, unique to the U.S. Department of Energy laboratories. These processes will ultimately support the submission of the base fuel qualification (BFQ) to the U.S. Nuclear Regulatory Commission (NRC) and revisions to High Performance Research Reactor Safety Analysis Reports to enable conversion from highly enriched uranium to LEU fuel. This quality assurance plan (QAP) provides the quality assurance requirements and processes that support the NRC BFQ. This QAP is designed to be used by project staff, and prescribes the required management control elements that are to be met and how they are implemented. Additional controls are captured in Fuel Thermo-Physical Characterization Project plans, existing procedures, and procedures to be developed that provide supplemental information on how work is conducted on the project.

  4. Global Threat Reduction Initiative Fuel Thermo-Physical Characterization Project: Sample Management Plan

    SciTech Connect

    Casella, Amanda J.; Pereira, Mario M.; Steen, Franciska H.

    2013-01-01

    This sample management plan provides guidelines for sectioning, preparation, acceptance criteria, analytical path, and end-of-life disposal for the fuel element segments utilized in the Global Threat Reduction Initiative (GTRI), Fuel Thermo-Physical Characterization Project. The Fuel Thermo-Physical Characterization Project is tasked with analysis of irradiated Low Enriched Uranium (LEU) Molybdenum (U-Mo) fuel element samples to support the GTRI conversion program. Sample analysis may include optical microscopy (OM), scanning electron microscopy (SEM) fuel-surface interface analysis, gas pycnometry (density) measurements, laser flash analysis (LFA), differential scanning calorimetry (DSC), thermogravimetry and differential thermal analysis with mass spectroscopy (TG /DTA-MS), Inductively Coupled Plasma Spectrophotometry (ICP), alpha spectroscopy, and Thermal Ionization Mass Spectroscopy (TIMS). The project will utilize existing Radiochemical Processing Laboratory (RPL) operating, technical, and administrative procedures for sample receipt, processing, and analyses. Test instructions (TIs), which are documents used to provide specific details regarding the implementation of an existing RPL approved technical or operational procedure, will also be used to communicate to staff project specific parameters requested by the Principal Investigator (PI). TIs will be developed, reviewed, and issued in accordance with the latest revision of the RPL-PLN-700, RPL Operations Plan. Additionally, the PI must approve all project test instructions and red-line changes to test instructions.

  5. Database of in-situ field measurements for estimates of fuel consumption and fire emissions in Siberia

    NASA Astrophysics Data System (ADS)

    Kukavskaya, Elena; Conard, Susan; Buryak, Ludmila; Ivanova, Galina; Soja, Amber; Kalenskaya, Olga; Zhila, Sergey; Zarubin, Denis; Groisman, Pavel

    2016-04-01

    Wildfires show great variability in the amount of fuel consumed and carbon emitted to the atmosphere. Various types of models are used to calculate global or large scale regional fire emissions. However, in the databases used to estimate fuel consumptions, data for Russia are typically under-represented. Meanwhile, the differences in vegetation and fire regimes in the boreal forests in North America and Eurasia argue strongly for the need of regional ecosystem-specific data. For about 15 years we have been collecting field data on fuel loads and consumption in different ecosystem types of Siberia. We conducted a series of experimental burnings of varying fireline intensity in Scots pine and larch forests of central Siberia to obtain quantitative and qualitative data on fire behavior and carbon emissions. In addition, we examined wildfire behavior and effects in different vegetation types including Scots pine, Siberian pine, fir, birch, poplar, and larch-dominated forests; evergreen coniferous shrubs; grasslands, and peats. We investigated various ecosystem zones of Siberia (central and southern taiga, forest-steppe, steppe, mountains) in the different subjects of the Russian Federation (Krasnoyarsk Kray, Republic of Khakassia, Republic of Buryatia, Tuva Republic, Zabaikalsky Kray). To evaluate the impact of forest practices on fire emissions, burned and unburned logged sites and forest plantations were examined. We found large variations of fuel consumption and fire emission rates among different vegetation types depending on growing conditions, fire behavior characteristics and anthropogenic factors. Changes in the climate system result in an increase in fire frequency, area burned, the number of extreme fires, fire season length, fire season severity, and the number of ignitions from lightning. This leads to an increase of fire-related emissions of carbon to the atmosphere. The field measurement database we compiled is required for improving accuracy of existing

  6. Roadmap for Development of Natural Gas Vehicle Fueling Infrastructructure and Analysis of Vehicular Natural Gas Consumption by Niche Sector

    SciTech Connect

    Stephen C. Yborra

    2007-04-30

    Vehicular natural gas consumption is on the rise, totaling nearly 200 million GGEs in 2005, despite declines in total NGV inventory in recent years. This may be attributed to greater deployment of higher fuel use medium- and heavy-duty NGVs as compared to the low fuel use of the natural gas-powered LDVs that exited the market through attrition, many of which were bi-fuel. Natural gas station counts are down to about 1100 from their peak of about 1300. Many of the stations that closed were under-utilized or not used at all while most new stations were developed with greater attention to critical business fundamentals such as site selection, projected customer counts, peak and off-peak fueling capacity needs and total station throughput. Essentially, the nation's NGV fueling infrastructure has been--and will continue--going through a 'market correction'. While current economic fundamentals have shortened payback and improved life-cycle savings for investment in NGVs and fueling infrastructure, a combination of grants and other financial incentives will still be needed to overcome general fleet market inertia to maintain status quo. Also imperative to the market's adoption of NGVs and other alternative fueled vehicle and fueling technologies is a clear statement of long-term federal government commitment to diversifying our nation's transportation fuel use portfolio and, more specifically, the role of natural gas in that policy. Based on the current NGV market there, and the continued promulgation of clean air and transportation policies, the Western Region is--and will continue to be--the dominant region for vehicular natural gas use and growth. In other regions, especially the Northeast, Mid-Atlantic states and Texas, increased awareness and attention to air quality and energy security concerns by the public and - more important, elected officials--are spurring policies and programs that facilitate deployment of NGVs and fueling infrastructure. Because of their high

  7. Dry additives-reduction catalysts for flue waste gases originating from the combustion of solid fuels

    SciTech Connect

    1995-12-31

    Hard coal is the basic energy generating raw material in Poland. In 1990, 60% of electricity and thermal energy was totally obtained from it. It means that 100 million tons of coal were burned. The second position is held by lignite - generating 38% of electricity and heat (67.3 million tons). It is to be underlined that coal combustion is particularly noxious to the environment. The coal composition appreciably influences the volume of pollution emitted in the air. The contents of incombustible mineral parts - ashes - oscillates from 2 to 30%; only 0.02 comes from plants that had once originated coal and cannot be separated in any way. All the rest, viz. the so-called external mineral substance enters the fuel while being won. The most indesirable hard coal ingredient is sulfur whose level depends on coal sorts and its origin. The worse the fuel quality, the more sulfur it contains. In the utilization process of this fuel, its combustible part is burnt: therefore, sulfur dioxide is produced. At the present coal consumption, the SO{sub 2} emission reaches the level of 3.2 million per year. The intensifies the pressure on working out new coal utilization technologies, improving old and developing of pollution limiting methods. Research is also directed towards such an adaptation of technologies in order that individual users may also make use thereof (household furnaces) as their share in the pollution emission is considerable.

  8. Tracked-vehicle fuel consumption. Final report on international test operations procedure

    SciTech Connect

    Not Available

    1987-05-18

    This document describes procedures for evaluating the fuel efficiency of tracked vehicles under controlled operating conditions. The test data are a major source for comparisons with similar vehicles, and can also serve to predict the operational range of these vehicles during tactical missions.

  9. Drive Cycle Analysis, Measurement of Emissions and Fuel Consumption of a PHEV School Bus: Preprint

    SciTech Connect

    Barnitt, R.; Gonder, J.

    2011-04-01

    The National Renewable Energy Laboratory (NREL) collected and analyzed real-world school bus drive cycle data and selected similar standard drive cycles for testing on a chassis dynamometer. NREL tested a first-generation plug-in hybrid electric vehicle (PHEV) school bus equipped with a 6.4L engine and an Enova PHEV drive system comprising a 25-kW/80 kW (continuous/peak) motor and a 370-volt lithium ion battery pack. A Bluebird 7.2L conventional school bus was also tested. Both vehicles were tested over three different drive cycles to capture a range of driving activity. PHEV fuel savings in charge-depleting (CD) mode ranged from slightly more than 30% to a little over 50%. However, the larger fuel savings lasted over a shorter driving distance, as the fully charged PHEV school bus would initially operate in CD mode for some distance, then in a transitional mode, and finally in a charge-sustaining (CS) mode for continued driving. The test results indicate that a PHEV school bus can achieve significant fuel savings during CD operation relative to a conventional bus. In CS mode, the tested bus showed small fuel savings and somewhat higher nitrogen oxide (NOx) emissions than the baseline comparison bus.

  10. Analysis of Technology Options to Reduce the Fuel Consumption of Idling Trucks

    SciTech Connect

    F. Stodolsky; L. Gaines; A. Vyas

    2000-06-01

    Long-haul trucks idling overnight consume more than 838 million gallons (20 million barrels) of fuel annually. Idling also emits pollutants. Truck drivers idle their engines primarily to (1) heat or cool the cab and/or sleeper, (2) keep the fuel warm in winter, and (3) keep the engine warm in the winter so that the engine is easier to start. Alternatives to overnight idling could save much of this fuel, reduce emissions, and cut operating costs. Several fuel-efficient alternatives to idling are available to provide heating and cooling: (1) direct-fired heater for cab/sleeper heating, with or without storage cooling; (2) auxiliary power units; and (3) truck stop electrification. Many of these technologies have drawbacks that limit market acceptance. Options that supply electricity are economically viable for trucks that are idled for 1,000-3,000 or more hours a year, while heater units could be used across the board. Payback times for fleets, which would receive quantity discounts on the prices, would be somewhat shorter.

  11. A repeated cross-sectional study of socio-economic inequities in dietary sodium consumption among Canadian adults: implications for national sodium reduction strategies

    PubMed Central

    2014-01-01

    Introduction In many countries including Canada, excess consumption of dietary sodium is common, and this has adverse implications for population health. Socio-economic inequities in sodium consumption seem likely, but research is limited. Knowledge of socio-economic inequities in sodium consumption is important for informing population-level sodium reduction strategies, to ensure that they are both impactful and equitable. Methods We examined the association between socio-economic indicators (income and education) and sodium, using two outcome variables: 1) sodium consumption in mg/day, and 2) reported use of table salt, in two national surveys: the 1970/72 Nutrition Canada Survey and the 2004 Canadian Community Health Survey, Cycle 2.2. This permitted us to explore whether there were any changes in socio-economic patterning in dietary sodium during a time period characterized by modest, information-based national sodium reduction efforts, as well as to provide baseline information against which to examine the impact (equitable or not) of future sodium reduction strategies in Canada. Results There was no evidence of a socio-economic inequity in sodium consumption (mg/day) in 2004. In fact findings pointed to a positive association in women, whereby women of higher education consumed more sodium than women of lower education in 2004. For men, income was positively associated with reported use of table salt in 1970/72, but negatively associated in 2004. Conclusions An emerging inequity in reported use of table salt among men could reflect the modest, information-based sodium reduction efforts that were implemented during the time frame considered. However, for sodium consumption in mg/day, we found no evidence of a contemporary inequity, and in fact observed the opposite effect among women. Our findings could reflect data limitations, or they could signal that sodium differs from some other nutrients in terms of its socio-economic patterning, perhaps reflecting very

  12. Effects of Village Power Quality on Fuel Consumption and Operating Expenses

    SciTech Connect

    Richard Wies; Ron Johnson

    2008-12-31

    Alaska's rural village electric utilities are isolated from the Alaska railbelt electrical grid intertie and from each other. Different strategies have been developed for providing power to meet demand in each of these rural communities. Many of these communities rely on diesel electric generators (DEGs) for power. Some villages have also installed renewable power sources and automated generation systems for controlling the DEGs and other sources of power. For example, Lime Village has installed a diesel battery photovoltaic hybrid system, Kotzebue and Wales have wind-diesel hybrid systems, and McGrath has installed a highly automated system for controlling diesel generators. Poor power quality and diesel engine efficiency in village power systems increases the cost of meeting the load. Power quality problems may consist of poor power factor (PF) or waveform disturbances, while diesel engine efficiency depends primarily on loading, the fuel type, the engine temperature, and the use of waste heat for nearby buildings. These costs take the form of increased fuel use, increased generator maintenance, and decreased reliability. With the cost of bulk fuel in some villages approaching $1.32/liter ($5.00/gallon) a modest 5% decrease in fuel use can result in substantial savings with short payback periods depending on the village's load profile and the cost of corrective measures. This project over its five year history has investigated approaches to improving power quality and implementing fuel savings measures through the use of performance assessment software tools developed in MATLAB{reg_sign} Simulink{reg_sign} and the implementation of remote monitoring, automated generation control, and the addition of renewable energy sources in select villages. The results have shown how many of these communities would benefit from the use of automated generation control by implementing a simple economic dispatch scheme and the integration of renewable energy sources such as wind

  13. Aeronautical fuel conservation possibilities for advanced subsonic transports. [application of aeronautical technology for drag and weight reduction

    NASA Technical Reports Server (NTRS)

    Braslow, A. L.; Whitehead, A. H., Jr.

    1973-01-01

    The anticipated growth of air transportation is in danger of being constrained by increased prices and insecure sources of petroleum-based fuel. Fuel-conservation possibilities attainable through the application of advances in aeronautical technology to aircraft design are identified with the intent of stimulating NASA R and T and systems-study activities in the various disciplinary areas. The material includes drag reduction; weight reduction; increased efficiency of main and auxiliary power systems; unconventional air transport of cargo; and operational changes.

  14. Influence of water on the reaction path of the oxygen reduction reaction in fuel cells

    NASA Astrophysics Data System (ADS)

    Malardier-Jugroot, Cecile; Groves, Michael; Jugroot, Manish

    2015-04-01

    The development of fuel cell technology has been limited in part due to the cost of the catalyst used in the cell and the rate limiting oxygen reduction reaction. We will present a molecular modelling study focus toward the prediction of improved durability and catalytic efficiency of the Platinum catalyst using doped graphene and doped single walled carbon nanotube surface. The most promising carbon supports - active centre systems were then studied in the gas phase and with explicit water molecules to model the oxygen reduction reaction and tailor the catalytic centres to improve the efficiency of this reaction while reducing the probability of occurrence of side reactions. Two major conclusions have been drawn from this analysis of the oxygen reduction reaction with and without water present. The doping of the carbon surface leads to a stronger platinum-surface interaction and does help the breaking of the oxygen-oxygen bond. These two are interrelated since the stronger surface-platinum bond allows for the same orbitals to interact with the oxygen-oxygen orbital. In addition, the dopants could make the surfaces more polar thus retaining water which might help catalyze the reaction, this property could be very promising to increase the effectiveness of fuel cell cathodes.

  15. Emission reduction from a diesel engine fueled by pine oil biofuel using SCR and catalytic converter

    NASA Astrophysics Data System (ADS)

    Vallinayagam, R.; Vedharaj, S.; Yang, W. M.; Saravanan, C. G.; Lee, P. S.; Chua, K. J. E.; Chou, S. K.

    2013-12-01

    In this work, we propose pine oil biofuel, a renewable fuel obtained from the resins of pine tree, as a potential substitute fuel for a diesel engine. Pine oil is endowed with enhanced physical and thermal properties such as lower viscosity and boiling point, which enhances the atomization and fuel/air mixing process. However, the lower cetane number of the pine oil hinders its direct use in diesel engine and hence, it is blended in suitable proportions with diesel so that the ignition assistance could be provided by higher cetane diesel. Since lower cetane fuels are prone to more NOX formation, SCR (selective catalyst reduction), using urea as reducing agent, along with a CC (catalytic converter) has been implemented in the exhaust pipe. From the experimental study, the BTE (brake thermal efficiency) was observed to be increased as the composition of pine oil increases in the blend, with B50 (50% pine oil and 50% diesel) showing 7.5% increase over diesel at full load condition. The major emissions such as smoke, CO, HC and NOX were reduced by 70.1%, 67.5%, 58.6% and 15.2%, respectively, than diesel. Further, the average emissions of B50 with SCR and CC assembly were observed to be reduced, signifying the positive impact of pine oil biofuel on atmospheric environment. In the combustion characteristics front, peak heat release rate and maximum in-cylinder pressure were observed to be higher with longer ignition delay.

  16. Thermodynamic and achievable efficiencies for solar-driven electrochemical reduction of carbon dioxide to transportation fuels

    NASA Astrophysics Data System (ADS)

    Singh, Meenesh R.; Clark, Ezra L.; Bell, Alexis T.

    2015-11-01

    Thermodynamic, achievable, and realistic efficiency limits of solar-driven electrochemical conversion of water and carbon dioxide to fuels are investigated as functions of light-absorber composition and configuration, and catalyst composition. The maximum thermodynamic efficiency at 1-sun illumination for adiabatic electrochemical synthesis of various solar fuels is in the range of 32-42%. Single-, double-, and triple-junction light absorbers are found to be optimal for electrochemical load ranges of 0-0.9 V, 0.9-1.95 V, and 1.95-3.5 V, respectively. Achievable solar-to-fuel (STF) efficiencies are determined using ideal double- and triple-junction light absorbers and the electrochemical load curves for CO2 reduction on silver and copper cathodes, and water oxidation kinetics over iridium oxide. The maximum achievable STF efficiencies for synthesis gas (H2 and CO) and Hythane (H2 and CH4) are 18.4% and 20.3%, respectively. Whereas the realistic STF efficiency of photoelectrochemical cells (PECs) can be as low as 0.8%, tandem PECs and photovoltaic (PV)-electrolyzers can operate at 7.2% under identical operating conditions. We show that the composition and energy content of solar fuels can also be adjusted by tuning the band-gaps of triple-junction light absorbers and/or the ratio of catalyst-to-PV area, and that the synthesis of liquid products and C2H4 have high profitability indices.

  17. Thermodynamic and achievable efficiencies for solar-driven electrochemical reduction of carbon dioxide to transportation fuels.

    PubMed

    Singh, Meenesh R; Clark, Ezra L; Bell, Alexis T

    2015-11-10

    Thermodynamic, achievable, and realistic efficiency limits of solar-driven electrochemical conversion of water and carbon dioxide to fuels are investigated as functions of light-absorber composition and configuration, and catalyst composition. The maximum thermodynamic efficiency at 1-sun illumination for adiabatic electrochemical synthesis of various solar fuels is in the range of 32-42%. Single-, double-, and triple-junction light absorbers are found to be optimal for electrochemical load ranges of 0-0.9 V, 0.9-1.95 V, and 1.95-3.5 V, respectively. Achievable solar-to-fuel (STF) efficiencies are determined using ideal double- and triple-junction light absorbers and the electrochemical load curves for CO2 reduction on silver and copper cathodes, and water oxidation kinetics over iridium oxide. The maximum achievable STF efficiencies for synthesis gas (H2 and CO) and Hythane (H2 and CH4) are 18.4% and 20.3%, respectively. Whereas the realistic STF efficiency of photoelectrochemical cells (PECs) can be as low as 0.8%, tandem PECs and photovoltaic (PV)-electrolyzers can operate at 7.2% under identical operating conditions. We show that the composition and energy content of solar fuels can also be adjusted by tuning the band-gaps of triple-junction light absorbers and/or the ratio of catalyst-to-PV area, and that the synthesis of liquid products and C2H4 have high profitability indices. PMID:26504215

  18. Thermodynamic and achievable efficiencies for solar-driven electrochemical reduction of carbon dioxide to transportation fuels

    PubMed Central

    Singh, Meenesh R.; Clark, Ezra L.; Bell, Alexis T.

    2015-01-01

    Thermodynamic, achievable, and realistic efficiency limits of solar-driven electrochemical conversion of water and carbon dioxide to fuels are investigated as functions of light-absorber composition and configuration, and catalyst composition. The maximum thermodynamic efficiency at 1-sun illumination for adiabatic electrochemical synthesis of various solar fuels is in the range of 32–42%. Single-, double-, and triple-junction light absorbers are found to be optimal for electrochemical load ranges of 0–0.9 V, 0.9–1.95 V, and 1.95–3.5 V, respectively. Achievable solar-to-fuel (STF) efficiencies are determined using ideal double- and triple-junction light absorbers and the electrochemical load curves for CO2 reduction on silver and copper cathodes, and water oxidation kinetics over iridium oxide. The maximum achievable STF efficiencies for synthesis gas (H2 and CO) and Hythane (H2 and CH4) are 18.4% and 20.3%, respectively. Whereas the realistic STF efficiency of photoelectrochemical cells (PECs) can be as low as 0.8%, tandem PECs and photovoltaic (PV)-electrolyzers can operate at 7.2% under identical operating conditions. We show that the composition and energy content of solar fuels can also be adjusted by tuning the band-gaps of triple-junction light absorbers and/or the ratio of catalyst-to-PV area, and that the synthesis of liquid products and C2H4 have high profitability indices. PMID:26504215

  19. Copper-substituted perovskite compositions for solid oxide fuel cell cathodes and oxygen reduction electrodes in other electrochemical devices

    DOEpatents

    Rieke, Peter C.; Coffey, Gregory W.; Pederson, Larry R.; Marina, Olga A.; Hardy, John S.; Singh, Prabhaker; Thomsen, Edwin C.

    2010-07-20

    The present invention provides novel compositions that find advantageous use in making electrodes for electrochemical cells. Also provided are electrochemical devices that include active oxygen reduction electrodes, such as solid oxide fuel cells, sensors, pumps and the like. The compositions comprises a copper-substituted ferrite perovskite material. The invention also provides novel methods for making and using the electrode compositions and solid oxide fuel cells and solid oxide fuel cell assemblies having cathodes comprising the compositions.

  20. Enhanced oxygen reduction activity and solid oxide fuel cell performance with a nanoparticles-loaded cathode.

    PubMed

    Zhang, Xiaomin; Liu, Li; Zhao, Zhe; Tu, Baofeng; Ou, Dingrong; Cui, Daan; Wei, Xuming; Chen, Xiaobo; Cheng, Mojie

    2015-03-11

    Reluctant oxygen-reduction-reaction (ORR) activity has been a long-standing challenge limiting cell performance for solid oxide fuel cells (SOFCs) in both centralized and distributed power applications. We report here that this challenge has been tackled with coloading of (La,Sr)MnO3 (LSM) and Y2O3 stabilized zirconia (YSZ) nanoparticles within a porous YSZ framework. This design dramatically improves ORR activity, enhances fuel cell output (200-300% power improvement), and enables superior stability (no observed degradation within 500 h of operation) from 600 to 800 °C. The improved performance is attributed to the intimate contacts between nanoparticulate YSZ and LSM particles in the three-phase boundaries in the cathode. PMID:25686380

  1. The impact of anti-congestion policies on fuel consumption, carbon dioxide emissions and urban sprawl: Application of RELU-TRAN2, a CGE model

    NASA Astrophysics Data System (ADS)

    Hiramatsu, Tomoru

    RELU-TRAN (Regional Economy and Land Use and Transportation) is a numerically solvable general equilibrium model (Anas and Liu, 2007), which treats in a unified manner the regional economy, urban land use and urban personal transportation sectors. In this dissertation, the model is extended by adding the consumer-workers' choice of private vehicle type according to the vehicle's fuel economy, by treating congestion on local roads as well as on major roads and by introducing car fuel consumption as a function of congested vehicle speed. By making the extensions, the model becomes more suitable to analyze the fuel consumption and CO2 emission consequences of urban development. The model is calibrated and simulated for the Chicago metropolitan area. By adjusting the model to the longer time span gradually, the shortand long-run price elasticities of fuel consumption are examined. As the time span becomes longer, fuel consumption becomes more elastic with respect to gasoline price, but when technological improvements in car fuel economy over comparable time spans are introduced exogenously, then the elasticity of fuel with respect to gasoline price becomes similar to that estimated in the econometric literature. Comparative statics exercises show that, if travel by auto becomes relatively more attractive in terms of travel time or travel cost than travel by public transit, then the Chicago MSA becomes more sprawled in total developed land area, whereas if public transit travel becomes relatively more attractive, then the Chicago MSA becomes more centralized. To mitigate fuel consumption and CO2 emissions, relative effectiveness of quasi-Pigouvian congestion tolls, a fuel tax on gasoline, a cordon toll around the downtown and a downtown parking fee are tested. All of these policies successfully reduce the aggregate fuel consumption and CO2. The urban growth boundary (UGB) is an alternative policy tested by the model. The UGB directly makes the Chicago MSA more

  2. Reducing Fuel Consumption through Semi-Automated Platooning with Class 8 Tractor Trailer Combinations (Poster)

    SciTech Connect

    Lammert, M.; Gonder, J.

    2014-07-01

    This poster describes the National Renewable Energy Laboratory's evaluation of the fuel savings potential of semi-automated truck platooning. Platooning involves reducing aerodynamic drag by grouping vehicles together and decreasing the distance between them through the use of electronic coupling, which allows multiple vehicles to accelerate or brake simultaneously. The NREL study addressed the need for data on American style line-haul sleeper cabs with modern aerodynamics and over a range of trucking speeds common in the United States.

  3. Fuel reduction at a Spanish heathland by prescribed fire and mechanical shredding: effects on seedling emergence.

    PubMed

    Fernández, Cristina; Vega, José A; Fonturbel, Teresa

    2013-11-15

    Traditional heathland burning has declined in Spain, leading to fuel accumulation and fuel reduction treatments have become common for severe wildfire hazard reduction. These methods need to maintain the botanical composition of those shrub communities. Prescribed fire has been widely used in the past, but we need to compare mechanical fuel reduction with prescribed fire because it is easier and safer to carry out in a wide range of weather conditions. This information could be particularly useful in flammable ecosystems all over the world where traditional anthropogenic burning has declined. In this study, we compared the effects of prescribed burning and mechanical shredding on the seedling emergence and its relation to the mature vegetation in a fire-prone heathland dominated by Erica australis L. and Pterospartum tridentatum (L.) Willk., in Galicia (NW Spain). We combined a greenhouse experiment with periodic field inventories of seedling emergence. In the greenhouse study, the seedling emergence was significantly higher in the soil samples after burning (383 seedlings m(-2)) than in samples before burning (242 seedlings m(-2)). In contrast, there was no significant difference in seedling density before and after mechanical shredding (243 compared with 261 seedlings m(-2)). Also, the number of seedlings that emerged after burning was significantly higher than that emerged after mechanical shredding. The maximum temperatures at the soil organic layer surface during burning were significantly and positively related to the density of Halimium lasianthum ssp. alyssoides and P. tridentatum seedlings. In the field study, the observed seedling density was very low both after prescribed burning and mechanical shredding. There was a high degree of similarity between emerged seedlings and mature vegetation in both the treated and in the untreated soils, which was probably a consequence of the dominance of resprouting species. Some consequences for the management of

  4. Impact of fuel quality regulation and speed reductions on shipping emissions: implications for climate and air quality.

    PubMed

    Lack, Daniel A; Cappa, Christopher D; Langridge, Justin; Bahreini, Roya; Buffaloe, Gina; Brock, Charles; Cerully, Kate; Coffman, Derek; Hayden, Katherine; Holloway, John; Lerner, Brian; Massoli, Paola; Li, Shao-Meng; McLaren, Robert; Middlebrook, Ann M; Moore, Richard; Nenes, Athanasios; Nuaaman, Ibraheem; Onasch, Timothy B; Peischl, Jeff; Perring, Anne; Quinn, Patricia K; Ryerson, Tom; Schwartz, Joshua P; Spackman, Ryan; Wofsy, Steven C; Worsnop, Doug; Xiang, Bin; Williams, Eric

    2011-10-15

    Atmospheric emissions of gas and particulate matter from a large ocean-going container vessel were sampled as it slowed and switched from high-sulfur to low-sulfur fuel as it transited into regulated coastal waters of California. Reduction in emission factors (EFs) of sulfur dioxide (SO₂), particulate matter, particulate sulfate and cloud condensation nuclei were substantial (≥ 90%). EFs for particulate organic matter decreased by 70%. Black carbon (BC) EFs were reduced by 41%. When the measured emission reductions, brought about by compliance with the California fuel quality regulation and participation in the vessel speed reduction (VSR) program, are placed in a broader context, warming from reductions in the indirect effect of SO₄ would dominate any radiative changes due to the emissions changes. Within regulated waters absolute emission reductions exceed 88% for almost all measured gas and particle phase species. The analysis presented provides direct estimations of the emissions reductions that can be realized by California fuel quality regulation and VSR program, in addition to providing new information relevant to potential health and climate impact of reduced fuel sulfur content, fuel quality and vessel speed reductions. PMID:21910443

  5. Simultaneous microbial and electrochemical reductions of vanadium (V) with bioelectricity generation in microbial fuel cells.

    PubMed

    Zhang, Baogang; Tian, Caixing; Liu, Ying; Hao, Liting; Liu, Ye; Feng, Chuanping; Liu, Yuqian; Wang, Zhongli

    2015-03-01

    Simultaneous microbial and electrochemical reductions of vanadium (V) with bioelectricity generation were realized in microbial fuel cells (MFCs). With initial V(V) concentrations of 75 mg/l and 150 mg/l in anolyte and catholyte, respectively, stable power output of 419±11 mW/m(2) was achieved. After 12h operation, V(V) concentration in the catholyte decreased to the value similar to that of the initial one in the anolyte, meanwhile it was nearly reduced completely in the anolyte. V(IV) was the main reduction product, which subsequently precipitated, acquiring total vanadium removal efficiencies of 76.8±2.9%. Microbial community analysis revealed the emergence of the new species of Deltaproteobacteria and Bacteroidetes as well as the enhanced Spirochaetes mainly functioned in the anode. This study opens new pathways to successful remediation of vanadium contamination. PMID:25536507

  6. Do biofuel blending mandates reduce gasoline consumption? Implications of state-level renewable fuel standards for energy security

    NASA Astrophysics Data System (ADS)

    Lim, Shinling

    In an effort to keep America's addiction to oil under control, federal and state governments have implemented a variety of policy measures including those that determine the composition of motor gasoline sold at the pump. Biofuel blending mandates known as Renewable Fuel Standards (RFS) are designed to reduce the amount of foreign crude oil needed to be imported as well as to boost the local ethanol and corn industry. Yet beyond looking at changes in gasoline prices associated with increased ethanol production, there have been no empirical studies that examine effects of state-level RFS implementation on gasoline consumption. I estimate a Generalized Least Squares model for the gasoline demand for the 1993 to 2010 period with state and time fixed effects controlling for RFS. States with active RFS are Minnesota, Hawaii, Missouri, Florida, Washington, and Oregon. I find that, despite the onset of federal biofuel mandates across states in 2007 and the lower energy content of blended gasoline, being in a state that has implemented RFS is associated with 1.5% decrease in gasoline consumption (including blended gasoline). This is encouraging evidence for efforts to lessen dependence on gasoline and has positive implications for energy security.

  7. Trajectory Optimization Using Adjoint Method and Chebyshev Polynomial Approximation for Minimizing Fuel Consumption During Climb

    NASA Technical Reports Server (NTRS)

    Nguyen, Nhan T.; Hornby, Gregory; Ishihara, Abe

    2013-01-01

    This paper describes two methods of trajectory optimization to obtain an optimal trajectory of minimum-fuel- to-climb for an aircraft. The first method is based on the adjoint method, and the second method is based on a direct trajectory optimization method using a Chebyshev polynomial approximation and cubic spine approximation. The approximate optimal trajectory will be compared with the adjoint-based optimal trajectory which is considered as the true optimal solution of the trajectory optimization problem. The adjoint-based optimization problem leads to a singular optimal control solution which results in a bang-singular-bang optimal control.

  8. Oxygen reduction kinetics on graphite cathodes in sediment microbial fuel cells.

    PubMed

    Renslow, Ryan; Donovan, Conrad; Shim, Matthew; Babauta, Jerome; Nannapaneni, Srilekha; Schenk, James; Beyenal, Haluk

    2011-12-28

    Sediment microbial fuel cells (SMFCs) have been used as renewable power sources for sensors in fresh and ocean waters. Organic compounds at the anode drive anodic reactions, while oxygen drives cathodic reactions. An understanding of oxygen reduction kinetics and the factors that determine graphite cathode performance is needed to predict cathodic current and potential losses, and eventually to estimate the power production of SMFCs. Our goals were to (1) experimentally quantify the dependence of oxygen reduction kinetics on temperature, electrode potential, and dissolved oxygen concentration for the graphite cathodes of SMFCs and (2) develop a mechanistic model. To accomplish this, we monitored current on polarized cathodes in river and ocean SMFCs. We found that (1) after oxygen reduction is initiated, the current density is linearly dependent on polarization potential for both SMFC types; (2) current density magnitude increases linearly with temperature in river SMFCs but remains constant with temperature in ocean SMFCs; (3) the standard heterogeneous rate constant controls the current density temperature dependence; (4) river and ocean SMFC graphite cathodes have large potential losses, estimated by the model to be 470 mV and 614 mV, respectively; and (5) the electrochemical potential available at the cathode is the primary factor controlling reduction kinetic rates. The mechanistic model based on thermodynamic and electrochemical principles successfully fit and predicted the data. The data, experimental system, and model can be used in future studies to guide SMFC design and deployment, assess SMFC current production, test cathode material performance, and predict cathode contamination. PMID:22052235

  9. Oxygen reduction kinetics on graphite cathodes in sediment microbial fuel cells†

    PubMed Central

    Renslow, Ryan; Donovan, Conrad; Shim, Matthew; Babauta, Jerome; Nannapaneni, Srilekha; Schenk, James

    2012-01-01

    Sediment microbial fuel cells (SMFCs) have been used as renewable power sources for sensors in fresh and ocean waters. Organic compounds at the anode drive anodic reactions, while oxygen drives cathodic reactions. An understanding of oxygen reduction kinetics and the factors that determine graphite cathode performance is needed to predict cathodic current and potential losses, and eventually to estimate the power production of SMFCs. Our goals were to (1) experimentally quantify the dependence of oxygen reduction kinetics on temperature, electrode potential, and dissolved oxygen concentration for the graphite cathodes of SMFCs and (2) develop a mechanistic model. To accomplish this, we monitored current on polarized cathodes in river and ocean SMFCs. We found that (1) after oxygen reduction is initiated, the current density is linearly dependent on polarization potential for both SMFC types; (2) current density magnitude increases linearly with temperature in river SMFCs but remains constant with temperature in ocean SMFCs; (3) the standard heterogeneous rate constant controls the current density temperature dependence; (4) river and ocean SMFC graphite cathodes have large potential losses, estimated by the model to be 470 mV and 614 mV, respectively; and (5) the electrochemical potential available at the cathode is the primary factor controlling reduction kinetic rates. The mechanistic model based on thermodynamic and electrochemical principles successfully fit and predicted the data. The data, experimental system, and model can be used in future studies to guide SMFC design and deployment, assess SMFC current production, test cathode material performance, and predict cathode contamination. PMID:22052235

  10. Accelerated creep in solid oxide fuel cell anode supports during reduction

    NASA Astrophysics Data System (ADS)

    Frandsen, H. L.; Makowska, M.; Greco, F.; Chatzichristodoulou, C.; Ni, D. W.; Curran, D. J.; Strobl, M.; Kuhn, L. T.; Hendriksen, P. V.

    2016-08-01

    To evaluate the reliability of solid oxide fuel cell (SOFC) stacks during operation, the stress field in the stack must be known. During operation the stress field will depend on time as creep processes relax stresses. The creep of reduced Ni-YSZ anode support at operating conditions has been studied previously. In this work a newly discovered creep phenomenon taking place during the reduction is reported. This relaxes stresses at a much higher rate (∼×104) than creep during operation. The phenomenon was studied both in three-point bending and uniaxial tension. Differences between the two measurements could be explained by newly observed stress promoted reduction. Finally, samples exposed to a small tensile stress (∼0.004 MPa) were observed to expand during reduction, which is in contradiction to previous literature. These observations suggest that release of internal residual stresses between the NiO and the YSZ phases occurs during reduction. The accelerated creep should practically eliminate any residual stress in the anode support in an SOFC stack, as has previously been indirectly observed. This phenomenon has to be taken into account both in the production of stacks and in the simulation of the stress field in a stack based on anode supported SOFCs.

  11. Supportless silver nanowires as oxygen reduction reaction catalysts for hydroxide-exchange membrane fuel cells.

    PubMed

    Alia, Shaun M; Duong, Kathlynne; Liu, Toby; Jensen, Kurt; Yan, Yushan

    2012-08-01

    Silver nanowires (AgNWs) and nanoparticles (AgNPs) have been synthesized to facilitate hydroxide-exchange membrane fuel cell development and commercialization. AgNWs and AgNPs with variable diameters (25-60 nm AgNWs, 2.4-30 nm AgNPs) have been studied with rotating-disk electrode experiments to examine the impact of size and morphology on the oxygen reduction reaction (ORR). Although a detrimental particle size effect is observed, AgNWs exceed the specific activity of bulk polycrystalline Ag. AgNWs with a diameter of 25 nm further exceed the ORR specific and mass activity of 2.4 nm AgNPs 5.3 times and by 16 %, respectively. Rotating ring-disk electrode testing demonstrates minimal peroxide formation on AgNWs; peroxide production increases with the use of AgNPs by as much as an order of magnitude and further increases with particle size reduction. Silver catalysts demonstrate alcohol tolerance for ORR, illustrating the benefit of silver and AgNWs as catalysts in hydroxide and alcohol hydroxide-based fuel cells. PMID:22887923

  12. The O2 reduction at the IFC modified O2 fuel cell electrode

    NASA Technical Reports Server (NTRS)

    Fielder, William L.; Singer, Joseph; Baldwin, Richard S.; Johnson, Richard E.

    1992-01-01

    The International Fuel Corporation (IFC) state of the art (SOA) O2 electrode (Au-10 percent Pt electrocatalyst by weight) is currently being used in the alkaline H2-O2 fuel cell in the NASA Space Shuttle. Recently, IFC modified O2 electrode, as a possible replacement for the SOA electrode. In the present study, O2 reduction data were obtained for the modified electrode at temperatures between 23.3 and 91.7 C. BET measurements gave an electrode BET surface area of about 2070 sq. cm/sq. cm of geometric surface area. The Tafel data could be fitted to two straight line regions. The slope for the lower region, designated as the 0.04 V/decade region, was temperature dependent, and the transfer coefficient was about 1.5. The 'apparent' energy of activation for this region was about 19 kcal/mol. An O2 reduction mechanism for this 0.04 region is presented. In the upper region, designated as the 0.08 V/decade region, diffusion may be the controlling process. Tafel data are presented to illustrate the increase in performance with increasing temperature.

  13. Limits to Understory Plant Restoration Following Fuel-Reduction Treatments in a Piñon-Juniper Woodland

    NASA Astrophysics Data System (ADS)

    Redmond, Miranda D.; Zelikova, Tamara J.; Barger, Nichole N.

    2014-11-01

    National fuel-reduction programs aim to reduce the risk of wildland fires to human communities and to restore forest and rangeland ecosystems to resemble their historical structure, function, and diversity. There are a number of factors, such as seed bank dynamics, post-treatment climate, and herbivory, which determine whether this latter goal may be achieved. Here, we examine the short-term (2 years) vegetation response to fuel-reduction treatments (mechanical mastication, broadcast burn, and pile burn) and seeding of native grasses on understory vegetation in an upland piñon-juniper woodland in southeast Utah. We also examine how wildlife herbivory affects the success of fuel-reduction treatments. Herbaceous cover increased in response to fuel-reduction treatments in all seeded treatments, with the broadcast burn and mastication having greater increases (234 and 160 %, respectively) in herbaceous cover than the pile burn (32 %). In the absence of seeding, herbaceous cover only increased in the broadcast burn (32 %). Notably, fuel-reduction treatments, but not seeding, strongly affected herbaceous plant composition. All fuel-reduction treatments increased the relative density of invasive species, especially in the broadcast burn, which shifted the plant community composition from one dominated by perennial graminoids to one dominated by annual forbs. Herbivory by wildlife reduced understory plant cover by over 40 % and altered plant community composition. If the primary management goal is to enhance understory cover while promoting native species abundance, our study suggests that mastication may be the most effective treatment strategy in these upland piñon-juniper woodlands. Seed applications and wildlife exclosures further enhanced herbaceous cover following fuel-reduction treatments.

  14. Limits to understory plant restoration following fuel-reduction treatments in a piñon-juniper woodland.

    PubMed

    Redmond, Miranda D; Zelikova, Tamara J; Barger, Nichole N

    2014-11-01

    National fuel-reduction programs aim to reduce the risk of wildland fires to human communities and to restore forest and rangeland ecosystems to resemble their historical structure, function, and diversity. There are a number of factors, such as seed bank dynamics, post-treatment climate, and herbivory, which determine whether this latter goal may be achieved. Here, we examine the short-term (2 years) vegetation response to fuel-reduction treatments (mechanical mastication, broadcast burn, and pile burn) and seeding of native grasses on understory vegetation in an upland piñon-juniper woodland in southeast Utah. We also examine how wildlife herbivory affects the success of fuel-reduction treatments. Herbaceous cover increased in response to fuel-reduction treatments in all seeded treatments, with the broadcast burn and mastication having greater increases (234 and 160 %, respectively) in herbaceous cover than the pile burn (32 %). In the absence of seeding, herbaceous cover only increased in the broadcast burn (32 %). Notably, fuel-reduction treatments, but not seeding, strongly affected herbaceous plant composition. All fuel-reduction treatments increased the relative density of invasive species, especially in the broadcast burn, which shifted the plant community composition from one dominated by perennial graminoids to one dominated by annual forbs. Herbivory by wildlife reduced understory plant cover by over 40 % and altered plant community composition. If the primary management goal is to enhance understory cover while promoting native species abundance, our study suggests that mastication may be the most effective treatment strategy in these upland piñon-juniper woodlands. Seed applications and wildlife exclosures further enhanced herbaceous cover following fuel-reduction treatments. PMID:25064466

  15. Environmentally Responsible Aviation: Propulsion Research to Enable Fuel Burn, Noise and Emissions Reduction

    NASA Technical Reports Server (NTRS)

    Van Zante, Dale; Suder, Kenneth

    2015-01-01

    The NASA Environmentally Responsible Aviation (ERA) program is maturing technologies to enable simultaneous reduction of fuel burn, noise and emissions from an aircraft engine system. Three engine related Integrated Technology Demonstrations (ITDs) have been completed at Glenn Research Center in collaboration with Pratt Whitney, General Electric and the Federal Aviation Administration. The engine technologies being matured are: a low NOx, fuel flexible combustor in partnership with Pratt Whitney; an ultra-high bypass, ducted propulsor system in partnership with Pratt Whitney and FAA; and high pressure ratio, front-stage core compressor technology in partnership with General Electric. The technical rationale, test configurations and overall results from the test series in each ITD are described. ERA is using system analysis to project the benefits of the ITD technologies on potential aircraft systems in the 2025 timeframe. Data from the ITD experiments were used to guide the system analysis assumptions. Results from the current assessments for fuel burn, noise and oxides of nitrogen emissions are presented.

  16. N-doped carbon nanomaterials are durable catalysts for oxygen reduction reaction in acidic fuel cells

    PubMed Central

    Shui, Jianglan; Wang, Min; Du, Feng; Dai, Liming

    2015-01-01

    The availability of low-cost, efficient, and durable catalysts for oxygen reduction reaction (ORR) is a prerequisite for commercialization of the fuel cell technology. Along with intensive research efforts of more than half a century in developing nonprecious metal catalysts (NPMCs) to replace the expensive and scarce platinum-based catalysts, a new class of carbon-based, low-cost, metal-free ORR catalysts was demonstrated to show superior ORR performance to commercial platinum catalysts, particularly in alkaline electrolytes. However, their large-scale practical application in more popular acidic polymer electrolyte membrane (PEM) fuel cells remained elusive because they are often found to be less effective in acidic electrolytes, and no attempt has been made for a single PEM cell test. We demonstrated that rationally designed, metal-free, nitrogen-doped carbon nanotubes and their graphene composites exhibited significantly better long-term operational stabilities and comparable gravimetric power densities with respect to the best NPMC in acidic PEM cells. This work represents a major breakthrough in removing the bottlenecks to translate low-cost, metal-free, carbon-based ORR catalysts to commercial reality, and opens avenues for clean energy generation from affordable and durable fuel cells. PMID:26601132

  17. Environmentally Responsible Aviation: Propulsion Research to Enable Fuel Burn, Noise and Emissions Reduction

    NASA Technical Reports Server (NTRS)

    Van Zante, Dale E.; Suder, Kenneth L.

    2015-01-01

    The NASA Environmentally Responsible Aviation (ERA) program is maturing technologies to enable simultaneous reduction of fuel burn, noise and emissions from an aircraft engine system. Three engine related Integrated Technology Demonstrations (ITDs) have been completed at Glenn Research Center in collaboration with Pratt Whitney, General Electric and the Federal Aviation Administration. The engine technologies being matured are a low NOx, fuel flexible combustor in partnership with Pratt Whitney, an ultra-high bypass, ducted propulsor system in partnership with Pratt Whitney FAA and high pressure ratio, front-stage core compressor technology in partnership with General Electric. The technical rationale, test configurations and overall results from the test series in each ITD are described. ERA is using system analysis to project the benefits of the ITD technologies on potential aircraft systems in the 2025 timeframe. Data from the ITD experiments were used to guide the system analysis assumptions. Results from the current assessments for fuel burn, noise and oxides of nitrogen emissions are presented.

  18. Pressure pyrolysed non-precious oxygen reduction catalysts for proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Nallathambi, Vijayadurga

    2011-12-01

    Worldwide energy demand has driven long-term efforts towards developing a clean, hydrogen-based energy economy. Polymer electrolyte membrane fuel cells (PEMFC) are low emissions and high efficiency devices that utilize the power of hydrogen and are a key enabling technology for the hydrogen economy. Carbon supported platinum-black is the state-of the art catalyst for oxygen reduction in a PEMFC because it can withstand the acidic environment. However, the high cost and low abundance of this precious metal has limited large-scale commercialization of PEMFCs. Current efforts focus on developing alternative inexpensive, non-noble metal-based catalysts for oxygen reduction with performance comparable to conventional platinum based electrocatalysts. In this work, inexpensive metal-nitrogen-carbon (MNC) catalysts have been synthesized by pyrolyzing transition metal and nitrogen precursors together with high surface area carbon materials in a closed, constant-volume quartz tube. High pressure generated due to nitrogen precursor evaporation lead to increased surface nitrogen content in the catalysts post-pyrolysis. Electrochemical oxygen reduction activity of MNC catalysts was analyzed using half-cell Rotating Ring Disc Electrode (RRDE) studies. The effect of nitrogen precursor morphology on the generation of active sites has been explored in detail. By increasing the Nitrogen/Carbon ratio of the nitrogen precursor, the accessible active site density increased by reducing carbon deposition in the pores of the carbon support during pyrolysis. The most active catalysts were obtained using melamine, having a N/C ratio of 2. Single PEMFC measurements employing MNC catalysts as cathodes indicated kinetic current density as high as 15 A cm-3 at 0.8 ViR-free and over 100 h of stable current at 0.5 V were observed. Effects of carbon free ammonia generating solid nitrogen precursors such as urea and ammonium carbamate were also studied. These precursors etched the carbon support

  19. Dependency of simultaneous Cr(VI), Cu(II) and Cd(II) reduction on the cathodes of microbial electrolysis cells self-driven by microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Zhang, Yong; Yu, Lihua; Wu, Dan; Huang, Liping; Zhou, Peng; Quan, Xie; Chen, Guohua

    2015-01-01

    Microbial fuel cells (MFCs) using either Cr(VI) (MFCsCr) or Cu(II) (MFCsCu) as a final electron acceptor, are stacked to self-drive microbial electrolysis cells (MECs) using Cd(II) (MECsCd) as an electron acceptor for simultaneous reduction of Cr(VI) in MFCsCr, Cu(II) in MFCsCu and Cd(II) in MECsCd with no external energy consumption. Titanium sheet (TS) and carbon rod (CR) as the cathodes of MECsCd are assessed for efficient system performance. MFCsCr and MFCsCu in series is superior to the parallel configuration, and higher Cd(II) reduction along with simultaneous Cr(VI) and Cu(II) reduction supports TS function as a good cathode material. Conversely, CR can not entirely proceed Cd(II) reduction in MECsCd despite of more Cr(VI) and Cu(II) reduction in the same serial configuration than either system alone. While a decrease in cathode volume in both MFCsCr and MFCsCu with serial connection benefits to reduction of Cr(VI) in MFCsCr and Cu(II) in MFCsCu, Cd(II) reduction in MECsCd is substantially enhanced under a decrease in cathode volume in individual MFCsCr and serially connected with volume-unchanged MFCsCu. This study demonstrates simultaneous Cr(VI), Cu(II) and Cd(II) recovery from MFCsCr-MFCsCu-MECsCd self-driven system is feasible, and TS as the cathodes of MECsCd is critical for efficient system performance.

  20. GENERIC VERIFICATION PROTOCOL FOR DETERMINATION OF EMISSIONS REDUCTIONS OBTAINED BY USE OF ALTERNATIVE OR REFORMULATED LIQUID FUELS, FUEL ADDITIVES, FUEL EMULSIONS AND LUBRICANTS FOR HIGHWAY AND NONROAD USE DISEL ENGINES AND LIGHT DUTY GASOLINE ENGINES AND VEHICLES

    EPA Science Inventory

    This report sets standards by which the emissions reduction provided by fuel and lubricant technologies can be tested and be tested in a comparable way. It is a generic protocol under the Environmental Technology Verification program.

  1. Pressure-vessel-damage fluence reduction by low-leakage fuel management. [PWR

    SciTech Connect

    Cokinos, D.; Aronson, A.L.; Carew, J.F.; Kohut, P.; Todosow, M.; Lois, L.

    1983-01-01

    As a result of neutron-induced radiation damage to the pressure vessel and of an increased concern that in a PWR transient the pressure vessel may be subjected to pressurized thermal shock (PTS), detailed analyses have been undertaken to determine the levels of neutron fluence accumulation at the pressure vessels of selected PWR's. In addition, various methods intended to limit vessel damage by reducing the vessel fluence have been investigated. This paper presents results of the fluence analysis and the evaluation of the low-leakage fuel management fluence reduction method. The calculations were performed with DOT-3.5 in an octant of the core/shield/vessel configuration using a 120 x 43 (r, theta) mesh structure.

  2. Retrieval Success from a 1950's UK Fuel Storage Pond: Blazing a Trail for Early Hazard Reduction

    SciTech Connect

    Bruce, S.

    2006-07-01

    Work has begun to tackle one of the biggest challenges in the UK nuclear cleanup program: the retrieval of spent nuclear fuel from the First Generation Magnox Fuel Storage Pond at Sellafield. The UK Government regulatory body, Nuclear Installations Inspectorate (NII) considers this pond to be the country's highest priority in terms of Hazard Reduction, a view supported by the facility owner, UK Government's Nuclear Decommissioning Authority (NDA). Remotely operated submersible vehicles (ROV's) were used by British Nuclear Group to assess the condition of stored fuel in First Generation Magnox Storage Ponds (1945-60's build). The ROV survey showed fuel condition was better than expected, and engineers were able to prototype retrieval on a selected skip (container) of fuel. The retrieval and subsequent export to the Fuel Handling Plant (FHP) was executed in November 2005 and was completely successful. The next stage is to reprocess the fuel using the Magnox Reprocessing Plant. If this is successful the prototype retrieval will have demonstrated that: - British Nuclear Group can safely retrieve fuel from its legacy ponds; - British Nuclear Group can safely transport retrieved legacy fuel between facilities; - British Nuclear Group can eliminate the hazard presented by this legacy fuel by use of existing on-site reprocessing facilities. This in turn enables the option to commence larger-scale fuel retrievals from these legacy ponds years ahead of the current plan which assumes new plants to be available to handle all arisings from the legacy ponds in 2015. This hazard reduction could commence as early as 2008. (authors)

  3. Performance of Thorium-Based Mixed Oxide Fuels for the Consumption of Plutonium and Minor Actinides in Current and Advanced Reactors

    SciTech Connect

    Weaver, Kevan Dean; Herring, James Stephen

    2002-06-01

    A renewed interest in thorium-based fuels has arisen lately based on the need for proliferation resistance, longer fuel cycles, higher burnup and improved wasteform characteristics. Recent studies have been directed toward homogeneously mixed, heterogeneously mixed, and seed-and-blanket thorium-uranium fuel cycles that rely on "in situ" use of the bred-in U-233. However, due to the higher initial enrichment required to achieve acceptable burnups, these fuels are encountering economic constraints. Thorium can nevertheless play a large role in the nuclear fuel cycle; particularly in the reduction of plutonium. While uranium-based mixedoxide (MOX) fuel will decrease the amount of plutonium, the reduction is limited due to the breeding of more plutonium (and higher actinides) from the U-238. Here we present calculational results and a comparison of the potential burnup of a thorium-based and uranium-based mixed oxide fuel in a light water reactor (LWR). Although the uranium-based fuels outperformed the thorium-based fuels in achievable burnup, a depletion comparison of the initially charged plutonium (both reactor and weapons grade) showed that the thorium-based fuels outperformed the uranium-based fuels by more that a factor of 2; where more than 70% of the total plutonium in the thorium-based fuel is consumed during the cycle. This is significant considering that the achievable burnup of the thorium-based fuels were 1.4 to 4.6 times less than the uranium-based fuels. Furthermore, use of a thorium-based fuel could also be used as a strategy for reducing the amount of long-lived nuclides (including the minor actinides), and thus the radiotoxicity in spent nuclear fuel. Although the breeding of U-233 is a concern, the presence of U-232 and its daughter products can aid in making this fuel self-protecting, and/or enough U-238 can be added to denature the fissile uranium. From these calculations, it appears that thorium-based fuel for plutonium incineration is superior as

  4. Progress in the Development of Oxygen Reduction Reaction Catalysts for Low-Temperature Fuel Cells.

    PubMed

    Li, Dongguo; Lv, Haifeng; Kang, Yijin; Markovic, Nenad M; Stamenkovic, Vojislav R

    2016-06-01

    We present a brief summary on the most recent progress in the design of catalysts for electrochemical reduction of oxygen. The main challenge in the wide spread of fuel cell technology is to lower the content of, or even eliminate, Pt and other precious metals in catalysts without sacrificing their performance. Pt-based nanosized catalysts with novel and refined architectures continue to dominate in catalytic performance, and formation of Pt-skin-like surfaces is key to achieving the highest values in activity. Moreover, durability has also been improved in Pt-based systems with addition of Au, which plays an important role in stabilizing the Pt topmost layers against dissolution. However, various carbon-based materials without precious metal have shown improvement in activity and durability and have been explored to serve as catalyst supports. Understanding how the doped elements interact with each other and/or carbon is challenging and necessary in the design of robust fuel cell catalysts. PMID:27070766

  5. Effect of reburning fuels and firing configuration on NOx reduction in a pulverized coal combustor

    SciTech Connect

    Zarnescu, V.; Hill, M.A.; Clark, D.A.; Pisupati, S.V.

    1998-12-31

    Throughout the world, more and more stringent regulations are being enacted to control acid rain precursors such as sulfur and nitrogen oxides from fossil fuel fired utility boilers. Therefore, there is an increasing need for the development and application of cost effective technologies for controlling these emissions. After several years of air pollution control innovation, the control of emissions of nitrogen oxide compounds stands out as an area where much work remains to be performed. The number of facilities that must consider NOx control is growing. Faced with increasingly strict limits on NOx emissions, electric utilities will need to consider the potential for implementing one of a wide variety of NOx control technologies. Reburning for NOx control stands out as a recognized, effective and mature technology that has been demonstrated on several coal-fired boilers in the US and worldwide. Because the application of NOx control technologies to a specific unit can impact boiler thermal characteristics (by affecting slagging, fouling and fly ash properties), efficiency and operation, there is a strong need to assess these potential impacts effectively. Therefore, tests on small-scale facilities are necessary as an intermediate step for testing on industrial scale units. The main objective of this investigation was to estimate and evaluate the impact of different reburning fuels and firing configurations on NOx reduction efficiency.

  6. Oxygen reduction reaction on Cu-doped Ag cluster for fuel-cell cathode.

    PubMed

    Ma, Wenqiang; Chen, Fuyi; Zhang, Nan; Wu, Xiaoqiang

    2014-10-01

    The development of fuel cells as clean-energy technologies is largely limited by the prohibitive cost of the noble-metal catalysts needed for catalyzing the oxygen reduction reaction (ORR) in fuel cells. A fundamental understanding of catalyst design principle that links material structures to the catalytic activity can accelerate the search for highly active and abundant bimetallic catalysts to replace platinum. Here, we present a first-principles study of ORR on Ag12Cu cluster in alkaline environment. The adsorptions of O2, OOH, and OH on Cu-doped Ag13 are stronger than on Ag13. The d-band centers of adsorption sites show the Cu-doping makes d-electrons transferred to higher energy state, and improves O2 dissociation. ORR processes on Ag12Cu and Ag13 indicate Cu-doping can strongly promote ORR, and ORR process can be better preformed on Ag12Cu than on Ag13. For four-electron transfer, the effective reversible potential is 0.401 V/RHE on Ag12Cu in alkaline medium. PMID:25227449

  7. Hexavalent chromium reduction and energy recovery by using dual-chambered microbial fuel cell.

    PubMed

    Gangadharan, Praveena; Nambi, Indumathi M

    2015-01-01

    Microbial fuel cell (MFC) technology is utilized to treat hexavalent chromium (Cr(VI)) from wastewater and to generate electricity simultaneously. The Cr(VI) is bioelectrochemically reduced to non-toxic Cr(III) form in the presence of an organic electron donor in a dual-chambered MFC. The Cr(VI) as catholyte and artificial wastewater inoculated with anaerobic sludge as anolyte, Cr(VI) at 100 mg/L was completely removed within 48 h (initial pH value 2.0). The total amount of Cr recovered was 99.87% by the precipitation of Cr(III) on the surface of the cathode. In addition to that 78.4% of total organic carbon reduction was achieved at the anode chamber within 13 days of operation. Furthermore, the maximum power density of 767.01 mW/m² (2.08 mA/m²) was achieved by MFCs at ambient conditions. The present work has successfully demonstrated the feasibility of using MFCs for simultaneous energy production from wastewater and reduction of toxic Cr(VI) to non-toxic Cr(III). PMID:25714633

  8. O2 reduction at the IFC orbiter fuel cell O2 electrode

    NASA Technical Reports Server (NTRS)

    Fielder, William L.; Singer, Joseph

    1990-01-01

    O2 reduction Tafel data were obtained for the IFC Orbiter fuel cell O2 electrode (Au-10 percent Pt catalyst) at temperatures between 24 and 81 C. BET measurements gave an electrode surface area of about 2040 sq cm per sq cm of geometric area. The Tafel data could be fitted to three straight line regions. For current densities less than 0.001 A/sq cm, the slope was essentially independent of temperature with a value of about 0.032 V/decade. Above 0.001 A/sq cm, the two regions, designated in the present study as the 0.04 and 0.12 V/decate regions, were temperature dependent. The apparent energies of activation for these two regions were about 9.3 and 6.5 kcal/mol, respectively. Tafel data (1 atmosphere O2) were extrapolated to 120 C for predicting changes in overpotential with increasing temperature. A mechanism is presented for O2 reduction.

  9. Enhanced microbial reduction of vanadium (V) in groundwater with bioelectricity from microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Hao, Liting; Zhang, Baogang; Tian, Caixing; Liu, Ye; Shi, Chunhong; Cheng, Ming; Feng, Chuanping

    2015-08-01

    Bioelectricity generated from the microbial fuel cell (MFC) is applied to the bioelectrical reactor (BER) directly to enhance microbial reduction of vanadium (V) (V(V)) in groundwater. With the maximum power density of 543.4 mW m-2 from the MFC, V(V) removal is accelerated with efficiency of 93.6% during 12 h operation. Higher applied voltage can facilitate this process. V(V) removals decrease with the increase of initial V(V) concentration, while extra addition of chemical oxygen demand (COD) has little effect on performance improvement. Microbial V(V) reduction is enhanced and then suppressed with the increase of conductivity. High-throughput 16S rRNA gene pyrosequencing analysis implies the accumulated Enterobacter and Lactococcus reduce V(V) with products from fermentative microorganisms such as Macellibacteroides. The presentation of electrochemically active bacteria as Enterobacter promotes electron transfers. This study indicates that application of bioelectricity from MFCs is a promising strategy to improve the efficiency of in-situ bioremediation of V(V) polluted groundwater.

  10. Hybrid binuclear-cobalt-phthalocyanine as oxygen reduction reaction catalyst in single chamber microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Li, Baitao; Zhou, Xiuxiu; Wang, Xiujun; Liu, Bingchuan; Li, Baikun

    2014-12-01

    A novel hybrid binuclear-cobalt-phthalocyanine (Bi-CoPc) is developed as the cathode catalyst to replace the costly platinum (Pt) in single chamber microbial fuel cells (SCMFCs). Bi-CoPc/C is integrated with metal oxides (NiO and CoO) to form macrocyclic complex for enhanced oxygen reduction rate (ORR). The characteristics of hybrid catalysts (Bi-CoPc/C-CoO and Bi-CoPc/C-NiO) are compared with Co-contained catalysts (CoPc/C and Bi-CoPc/C) and metal oxide catalysts (NiO and CoO). The increase in O and N functional groups indicates the benefits of NiO and CoO to the cathode catalysts. The cyclic voltammetry (CV) shows the reduction peak for Bi-CoPc/C-NiO and Bi-CoPc/C-CoO at -0.12 V and -0.22 V, respectively. The power densities (368 mW m-2 and 400 mW m-2) of SCMFCs with Bi-CoPc/C-CoO and Bi-CoPc-NiO/C are the highest among the cathodes tested, and close to that of Pt (450 mW m-2). This study demonstrates that hybrid Bi-CoPc/C with metal oxides has a great potential as a cost-effective catalyst in MFCs.

  11. Polypyrrole/carbon black composite as a novel oxygen reduction catalyst for microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Yuan, Yong; Zhou, Shungui; Zhuang, Li

    A polypyrrole/carbon black (Ppy/C) composite has been employed as an electrocatalyst for the oxygen reduction reaction (ORR) in an air-cathode microbial fuel cell (MFC). The electrocatalytic activity of the Ppy/C is evaluated toward the oxygen reduction using cyclic voltammogram and linear sweep voltammogram methods. In comparison with that at the carbon black electrode, the peak potential of the ORR at the Pp/C electrode shifts by approximate 260 mV towards positive potential, demonstrating the electrocatalytic activity of Ppy toward ORR. Additionally, the results of the MFC experiments show that the Ppy/C is well suitable to fully substitute the traditional cathode materials in MFCs. The maximum power density of 401.8 mW m -2 obtained from the MFC with a Ppy/C cathode is higher than that of 90.9 mW m -2 with a carbon black cathode and 336.6 mW m -2 with a non-pyrolysed FePc cathode. Although the power output with a Ppy/C cathode is lower than that with a commercial Pt cathode, the power per cost of a Ppy/C cathode is 15 times greater than that of a Pt cathode. Thus, the Ppy/C can be a good alternative to Pt in MFCs due to the economic advantage.

  12. Agricultural Bio-Fueled Generation of Electricity and Development of Durable and Efficent NOx Reduction

    SciTech Connect

    Boyd, Rodney

    2007-08-08

    The objective of this project was to define the scope and cost of a technology research and development program that will demonstrate the feasibility of using an off-the-shelf, unmodified, large bore diesel powered generator in a grid-connected application, utilizing various blends of BioDiesel as fuel. Furthermore, the objective of project was to develop an emissions control device that uses a catalytic process and BioDiesel (without the presence of Ammonia or Urea)to reduce NOx and other pollutants present in a reciprocating engine exhaust stream with the goal of redefining the highest emission reduction efficiencies possible for a diesel reciprocating generator. Process: Caterpillar Power Generation adapted an off-the-shelf Diesel Generator to run on BioDiesel and various Petroleum Diesel/BioDiesel blends. EmeraChem developed and installed an exhaust gas cleanup system to reduce NOx, SOx, volatile organics, and particulates. The system design and function was optimized for emissions reduction with results in the 90-95% range;

  13. Alcohol consumption in the Arab region: What do we know, why does it matter, and what are the policy implications for youth harm reduction?

    PubMed

    Ghandour, Lilian; Chalak, Ali; El-Aily, Aida; Yassin, Nasser; Nakkash, Rima; Tauk, Mitra; El Salibi, Noura; Heffron, Meghan; Afifi, Rima

    2016-02-01

    Alcohol is a recognized global risk factor for many diseases and injury types and a major contributor to disability and death. While cost-effective interventions do exist, many countries lack a comprehensive national alcohol harm reduction policy. The Arab world includes 22 diverse countries stretching from North Africa to Western Asia having varying dispositions with regards to alcohol sale and consumption. Epidemiological data is scattered and the picture on alcohol consumption remains blurry. This paper presents the findings of an extensive review conducted on all 22 Arab countries, specifically describing: (1) the density and methodology of alcohol-related peer-reviewed publications over the last two decades (1993-2013); (2) the epidemiology of alcohol consumption given all available data; and (3) the current status of policies in the region. Our search revealed a strikingly low number of alcohol-related peer-reviewed published studies - a total of 81 publications across 22 countries and two decades. Most studies are based on clinical or student samples. Where data is available, age of onset is low and drinking is frequent, in the absence of any available or enforced harm reduction policies. We submit that countries in the Arab region can be divided into four categories by alcohol ban and published data. One category includes countries where alcohol is not banned but data is absent, suggesting an ostrich-like response to a controversial behavior, or reflecting a weak research infrastructure and/or policy landscape. Evidence-informed recommendations and future directions for policy and research are discussed and tailored to countries' current stance on alcohol legislation and consumption. Given the particular vulnerability of youth to uptake of alcohol as well as the resulting short and long term consequences, the paper concludes by focusing on the implications of the findings for youth alcohol harm reduction. PMID:26547300

  14. Trends in the size distribution, highway use, and consumption of gasoline and diesel fuels of the U.S. Commercial Truck Fleet, 1977-2002.

    SciTech Connect

    Bertram, K. M.; Santini, D. J.; Anderson, J. L.; Vyas, A. D.

    2008-01-01

    This paper focuses on various major long-range (1977-2002, 1982-2002) U.S. commercial trucking trends by using U.S. Department of Commerce, Bureau of the Census Vehicle/Truck Inventory and Use Survey (VIUS/TIUS) data from this period, as well as selected 1977-2002 data from the U.S. Department of Energy's (DOE's) Energy Information Administration (EIA) and the U.S. Department of Transportation, Federal Highway Administration's (FHWA's) Highway Statistics. Analyses are made of (1) overall passenger vehicle versus truck consumption patterns of gasoline and diesel fuel and (2) the population growth and fuels used by all commercial truck classes and selected truck types (single unit and combination). Selected vehicle miles traveled, gallons per vehicle miles traveled, and gallons per cargo ton-miles traveled trends, as well as the effect of cargo tons per truck on fuel consumption, are also assessed. In addition, long-range trends of related factors (such as long-haul mileages driven by heavy trucks) and their impacts on both reducing fuel consumption per cargo-ton-mile and the relative shares of total commercial fuel use among truck classes were examined. Results of these trends on U.S. petroleum consumption are identified. The effects of basic engineering design and performance, national Interstate highway construction legislation, national demographic trends (such as suburbanization), and changes in U.S. corporate operational requirements are discussed. Their impacts on both the long-distance hauling and shorter-distance urban and suburban delivery markets of the commercial trucking industry are highlighted.

  15. Fuel Reduction Effect of the Solar Cell and Diesel Engine Hybrid System with a Prediction Algorithm of Solar Power Generation

    NASA Astrophysics Data System (ADS)

    Obara, Shin'ya; Tanno, Itaru

    Green energy utilization technology is an effective means of reducing greenhouse gas emissions. In this paper, the production-of-electricity prediction algorithm (PAS) of the solar cell was developed. In PAS, a layered neural network is made to learn based on past weather data and the operation plan of the hybrid system (proposed system) of a solar cell and a diesel engine generator was examined using this prediction algorithm. In addition, system operation without a electricity-storage facility, and the system with the engine generator operating at 25% or less of battery residual quantity was investigated, and the fuel consumption of each system was measured. Numerical simulation showed that the fuel consumption of the proposed system was modest compared with other operating methods. However, there was a significant difference in the prediction error of the electricity production of the solar cell and the actual value, and the proposed system was shown to be not always superior to others. Moreover, although there are errors in the predicted and actual values using PAS, there is no significant influence in the operation plan of the proposed system in almost all cases. In the operation plan of the system with PAS, there was a case where the fuel consumption decreased by 15% compared with other systems.

  16. Extraction and reductive stripping of pertechnetate from spent nuclear fuel waste streams.

    SciTech Connect

    Shkrob, I.; Marin, T.; Stepinski, D.; Vandegrift, G.; Muntean, J.; Dietz, M.

    2011-01-01

    An approach directed at rapid sequestration and disposal of technetium-99 from UREX (uranium extraction) liquid waste streams is presented. This stream is generated during reprocessing of light-water-reactor spent fuel to recycle the actinides and separate fission products for waste disposal. U and Tc are co-extracted from a nitric acid solution using tri-n-butylphosphate in dodecane, so that Tc(VII) is present in the strip solution after the actinide separations. The goal is to separate uranyl from the pertechnetate in this U-Tc stream and then sequester Tc in the metallic form. Our approach is based on reductive stripping of pertechnetate either from aqueous solution (for column extractions) or organic solvents (for liquid-liquid extractions). In both of these methods, metallic zinc in the presence of formic acid serves as a reducing agent, and {sup 99}Tc is recovered as a co-precipitate of Zn(II) hydroxide and hydrous Tc(IV) oxide, with a Zn:Tc ratio between 1:1 and 2:1 mol/mol. This solid residue can be reduced to a Zn-Tc alloy by high temperature (500-700 C) hydrogenation, and the resulting heterophase alloy can be added to a metallic Fe-Zr-Mo waste form that is processed at 1600 C, with subsequent loss of Zn by evaporation. Alternatively, Zn and Tc can be separated and {sup 99}Tc sequestered as NH{sub 4}TcO{sub 4} for further reduction to Tc(0) metal. The aqueous Zn reduction process removes {approx}90% of {sup 99}Tc per cycle. The nonaqueous Zn reduction in 1:1 methanol-formic acid removes 60-70% of {sup 99}Tc per cycle, depending on the extracting agent (such as a tetraalkylammonium nitrate). The extracting agent is recycled in the process. The pertechnetate is extracted from the aqueous phase into 1,2-dichloroethane, which is removed by evaporation and reused. The residue is either calcined and steam reformed to Tc(0) or processed by the nonaqueous Zn reduction method. These methods can be used not only to remove the pertechnetate from the U-Tc product

  17. Estimating the climate and air quality benefits of aviation fuel and emissions reductions

    NASA Astrophysics Data System (ADS)

    Dorbian, Christopher S.; Wolfe, Philip J.; Waitz, Ian A.

    2011-05-01

    In this study we consider the implications of our current understanding of aviation climate impacts as it relates to the ratio of non-CO 2 to CO 2 effects from aviation. We take as inputs recent estimates from the literature of the magnitude of the component aviation impacts and associated uncertainties. We then employ a simplified probabilistic impulse response function model for the climate and a range of damage functions to estimate the ratio of non-CO 2 to CO 2 impacts of aviation for a range of different metrics, scientific assumptions, future background emissions scenarios, economic growth scenarios, and discount rates. We take cost-benefit analysis as our primary context and thus focus on integral metrics that can be related to damages: the global warming potential, the time-integrated change in surface temperature, and the net present value of damages. We also present results based on an endpoint metric, the global temperature change potential. These latter results would be more appropriate for use in a cost-effectiveness framework (e.g., with a well-defined policy target for the anthropogenic change in surface temperature at a specified time in the future). We find that the parameter that most influences the ratio of non-CO 2 to CO 2 impacts of aviation is the discount rate, or analogously the time window used for physical metrics; both are expressions of the relative importance of long-lived versus short-lived impacts. Second to this is the influence of the radiative forcing values that are assumed for aviation-induced cloudiness effects. Given the large uncertainties in short-lived effects from aviation, and the dominating influence of discounting or time-windowing, we find that the choice of metric is relatively less influential. We express the ratios of non-CO 2 to CO 2 impacts on a per unit fuel burn basis so that they can be multiplied by a social cost of carbon to estimate the additional benefits of fuel burn reductions from aviation beyond those

  18. A lithium-air fuel cell using copper to catalyze oxygen-reduction based on copper-corrosion mechanism.

    PubMed

    Wang, Yonggang; Zhou, Haoshen

    2010-09-14

    The copper-catalyzed O(2) reduction in aqueous electrolyte and the Li-anode in organic electrolyte were united together by a ceramic Li-ions exchange film to form a lithium-air fuel cell. The achieved results demonstrate the cycle between Cu and Cu(2)O can be used to catalyze O(2) electrochemical reduction based on the copper-corrosion mechanism. PMID:20668776

  19. Opportunities to reduce consumption of natural uranium in reactor SVBR-75/100 when changing over to the closed fuel cycle

    SciTech Connect

    Toshinsky, G.I.; Komlev, O.G.; Mel'nikov, K.G.; Novikova, N.N.

    2007-07-01

    contrast to the cost of electricity produced by thermal power plants using fossil fuel. At the same time, the available resources of natural uranium are increasing progressively with increase of its cost. The expenditure caused by changeover to the closed NFC will be less, if plutonium extracted from the own SNF of uranium loads is used in fabrication of the first MOX fuel loads. If the oxide uranium fuel is used, by the end of the lifetime a comparatively high breeding ratio (BR) ({approx}0.84) provides a sufficiently high content of plutonium in the SNF that may be used in the next fuel lifetimes when organizing the closed fuel cycle. Moreover, the own SNF of starting loads from oxide uranium fuel contains large quantity of unburned uranium-235 that is expedient to use for forming load for the next lifetime. From the very beginning of realization of the extended program on implementation of reactors SVBR-75/100 in the NP, use of plutonium extracted from the TRs' SNF for forming the starting loads of those reactors for the purpose of total elimination of natural uranium consumption will be more expensive as compared with the considered variant of changeover from the opened NFC to the closed NFC. This is conditioned by the fact that for the plutonium extracted from the TRs' SNF, the plutonium cost determined by a volume of SNF reprocessing per ton of plutonium will be several times higher as compared with its cost in case of using the own SNF because of considerably less content of plutonium in the TRs' SNF. It should be taken into account that the organization of the enterprise on large-scale reprocessing of TRs' SNF and MOX fuel fabrication must precede the construction of NPPs with FRs. Thus, the demands in investments are increased. At the same time, for the proposed changeover from the opened NFC to the closed one the construction of the closed NFC enterprise may be long postponed from FR launching that reduces the investment demands. At this, as the assessments have

  20. Role of fuel carbon intensity in achieving 2050 greenhouse gas reduction goals within the light-duty vehicle sector.

    PubMed

    Melaina, M; Webster, K

    2011-05-01

    Recent U.S. climate change policy developments include aggressive proposals to reduce greenhouse gas emissions, including cap-and-trade legislation with a goal of an 83% reduction below 2005 levels by 2050. This study examines behavioral and technological changes required to achieve this reduction within the light-duty vehicle (LDV) sector. Under this "fair share" sectoral assumption, aggressive near-term actions are necessary in three areas: vehicle miles traveled (VMT), vehicle fuel economy (FE), and fuel carbon intensity (FCI). Two generic scenarios demonstrate the important role of FCI in meeting the 2050 goal. The first scenario allows deep reductions in FCI to compensate for relatively modest FE improvements and VMT reductions. The second scenario assumes optimistic improvements in FE, relatively large reductions in VMT and less aggressive FCI reductions. Each generic scenario is expanded into three illustrative scenarios to explore the theoretical implications of meeting the 2050 goal by relying exclusively on biofuels and hybrid vehicles, biofuels and plug-in hybrid vehicles, or hydrogen fuel cell electric vehicles. These scenarios inform a discussion of resource limitations, technology development and deployment challenges, and policy goals required to meet the 2050 GHG goal for LDVs. PMID:21456550

  1. Supermarket Healthy Eating for Life (SHELf): protocol of a randomised controlled trial promoting healthy food and beverage consumption through price reduction and skill-building strategies

    PubMed Central

    2011-01-01

    Background In the context of rising food prices, there is a need for evidence on the most effective approaches for promoting healthy eating. Individually-targeted behavioural interventions for increasing food-related skills show promise, but are unlikely to be effective in the absence of structural supports. Fiscal policies have been advocated as a means of promoting healthy eating and reducing obesity and nutrition-related disease, but there is little empirical evidence of their effectiveness. This paper describes the Supermarket Healthy Eating for LiFe (SHELf) study, a randomised controlled trial to investigate effectiveness and cost-effectiveness of a tailored skill-building intervention and a price reduction intervention, separately and in combination, against a control condition for promoting purchase and consumption of healthy foods and beverages in women from high and low socioeconomic groups. Methods/design SHELf comprises a randomised controlled trial design, with participants randomised to receive either (1) a skill-building intervention; (2) price reductions on fruits, vegetables and low-joule soft drink beverages and water; (3) a combination of skill-building and price reductions; or (4) a control condition. Five hundred women from high and low socioeconomic areas will be recruited through a store loyalty card program and local media. Randomisation will occur on receipt of informed consent and baseline questionnaire. An economic evaluation from a societal perspective using a cost-consequences approach will compare the costs and outcomes between intervention and control groups. Discussion This study will build on a pivotal partnership with a major national supermarket chain and the Heart Foundation to investigate the effectiveness of intervention strategies aimed at increasing women's purchasing and consumption of fruits and vegetables and decreased purchasing and consumption of sugar-sweetened beverages. It will be among the first internationally to

  2. Nanostructured Catalyst Systems for Fuel Cells: Synthesis and Characterization of Low Platinum Content Electrocatalysts for O{sub 2} Reduction

    SciTech Connect

    Adzic, Radoslav

    2007-02-01

    The objective of this project is to synthesize and characterize new O{sub 2} reduction catalysts with enhanced activity and ultra low Pt loading, and to test them in membrane electrode assemblies (MEAs) to determine their performance under fuel cell cathode operating conditions.

  3. Continuum and Quantum-Chemical Modeling of Oxygen Reduction on the Cathode in a Solid Oxide Fuel Cell

    SciTech Connect

    Choi, Yongman; Mebane, David S.; Wang, Jeng-Han; Liu, Meilin

    2009-10-08

    Solid oxide fuel cells (SOFCs) have several advantages over other types of fuels cells such as high-energy efficiency and excellent fuel flexibility. To be economically competitive, however, new materials with extraordinary transport and catalytic properties must be developed to dramatically improve the performance while reducing the cost. This article reviews recent advancements in understanding oxygen reduction on various cathode materials using phenomenological and quantum chemical approaches in order to develop novel cathode materials with high catalytic activity toward oxygen reduction. We summarize a variety of results relevant to understanding the interactions between O2 and cathode materials at the molecular level as predicted using quantum-chemical cal-culations and probed using in situ surface vibrational spectroscopy. It is hoped that this in-depth understanding may provide useful insights into the design of novel cath-ode materials for a new generation of SOFCs.

  4. Separation and Recovery of Uranium Metal from Spent Light Water Reactor Fuel via Electrolytic Reduction and Electrorefining

    SciTech Connect

    S. D. Herrmann; S. X. Li

    2010-09-01

    A series of bench-scale experiments was performed in a hot cell at Idaho National Laboratory to demonstrate the separation and recovery of uranium metal from spent light water reactor (LWR) oxide fuel. The experiments involved crushing spent LWR fuel to particulate and separating it from its cladding. Oxide fuel particulate was then converted to metal in a series of six electrolytic reduction runs that were performed in succession with a single salt loading of molten LiCl – 1 wt% Li2O at 650 °C. Analysis of salt samples following the series of electrolytic reduction runs identified the diffusion of select fission products from the spent fuel to the molten salt electrolyte. The extents of metal oxide conversion in the post-test fuel were also quantified, including a nominal 99.7% conversion of uranium oxide to metal. Uranium metal was then separated from the reduced LWR fuel in a series of six electrorefining runs that were performed in succession with a single salt loading of molten LiCl-KCl-UCl3 at 500 °C. Analysis of salt samples following the series of electrorefining runs identified additional partitioning of fission products into the molten salt electrolyte. Analyses of the separated uranium metal were performed, and its decontamination factors were determined.

  5. Minimum Specific Fuel Consumption of a Liquid-Cooled Multicylinder Aircraft Engine as Affected by Compression Ratio and Engine Operating Conditions

    NASA Technical Reports Server (NTRS)

    Brun, Rinaldo J.; Feder, Melvin S.; Harries, Myron L.

    1947-01-01

    An investigation was conducted on a 12-cylinder V-type liquid-cooled aircraft engine of 1710-cubic-inch displacement to determine the minimum specific fuel consumption at constant cruising engine speed and compression ratios of 6.65, 7.93, and 9.68. At each compression ratio, the effect.of the following variables was investigated at manifold pressures of 28, 34, 40, and 50 inches of mercury absolute: temperature of the inlet-air to the auxiliary-stage supercharger, fuel-air ratio, and spark advance. Standard sea-level atmospheric pressure was maintained at the auxiliary-stage supercharger inlet and the exhaust pressure was atmospheric. Advancing the spark timing from 34 deg and 28 deg B.T.C. (exhaust and intake, respectively) to 42 deg and 36 deg B.T.C. at a compression ratio of 6.65 resulted in a decrease of approximately 3 percent in brake specific fuel consumption. Further decreases in brake specific fuel consumption of 10.5 to 14.1 percent (depending on power level) were observed as the compression ratio was increased from 6.65 to 9.68, maintaining at each compression ratio the spark advance required for maximum torque at a fuel-air ratio of 0.06. This increase in compression ratio with a power output of 0.585 horsepower per cubic inch required a change from . a fuel- lend of 6-percent triptane with 94-percent 68--R fuel at a compression ratio of 6.65 to a fuel blend of 58-percent, triptane with 42-percent 28-R fuel at a compression ratio of 9.68 to provide for knock-free engine operation. As an aid in the evaluation of engine mechanical endurance, peak cylinder pressures were measured on a single-cylinder engine at several operating conditions. Peak cylinder pressures of 1900 pounds per square inch can be expected at a compression ratio of 9.68 and an indicated mean effective pressure of 320 pounds per square inch. The engine durability was considerably reduced at these conditions.

  6. The relationship between air pollution, fossil fuel energy consumption, and water resources in the panel of selected Asia-Pacific countries.

    PubMed

    Rafindadi, Abdulkadir Abdulrashid; Yusof, Zarinah; Zaman, Khalid; Kyophilavong, Phouphet; Akhmat, Ghulam

    2014-10-01

    The objective of the study is to examine the relationship between air pollution, fossil fuel energy consumption, water resources, and natural resource rents in the panel of selected Asia-Pacific countries, over a period of 1975-2012. The study includes number of variables in the model for robust analysis. The results of cross-sectional analysis show that there is a significant relationship between air pollution, energy consumption, and water productivity in the individual countries of Asia-Pacific. However, the results of each country vary according to the time invariant shocks. For this purpose, the study employed the panel least square technique which includes the panel least square regression, panel fixed effect regression, and panel two-stage least square regression. In general, all the panel tests indicate that there is a significant and positive relationship between air pollution, energy consumption, and water resources in the region. The fossil fuel energy consumption has a major dominating impact on the changes in the air pollution in the region. PMID:24898296

  7. Advection of surface-derived organic carbon fuels microbial reduction in Bangladesh groundwater

    PubMed Central

    Mailloux, Brian J.; Trembath-Reichert, Elizabeth; Cheung, Jennifer; Watson, Marlena; Stute, Martin; Freyer, Greg A.; Ferguson, Andrew S.; Ahmed, Kazi Matin; Alam, Md. Jahangir; Buchholz, Bruce A.; Thomas, James; Layton, Alice C.; Zheng, Yan; Bostick, Benjamin C.; van Geen, Alexander

    2013-01-01

    Chronic exposure to arsenic (As) by drinking shallow groundwater causes widespread disease in Bangladesh and neighboring countries. The release of As naturally present in sediment to groundwater has been linked to the reductive dissolution of iron oxides coupled to the microbial respiration of organic carbon (OC). The source of OC driving this microbial reduction—carbon deposited with the sediments or exogenous carbon transported by groundwater—is still debated despite its importance in regulating aquifer redox status and groundwater As levels. Here, we used the radiocarbon (14C) signature of microbial DNA isolated from groundwater samples to determine the relative importance of surface and sediment-derived OC. Three DNA samples collected from the shallow, high-As aquifer and one sample from the underlying, low-As aquifer were consistently younger than the total sediment carbon, by as much as several thousand years. This difference and the dominance of heterotrophic microorganisms implies that younger, surface-derived OC is advected within the aquifer, albeit more slowly than groundwater, and represents a critical pool of OC for aquifer microbial communities. The vertical profile shows that downward transport of dissolved OC is occurring on anthropogenic timescales, but bomb 14C-labeled dissolved OC has not yet accumulated in DNA and is not fueling reduction. These results indicate that advected OC controls aquifer redox status and confirm that As release is a natural process that predates human perturbations to groundwater flow. Anthropogenic perturbations, however, could affect groundwater redox conditions and As levels in the future. PMID:23487743

  8. Simulation of the reduction process of solid oxide fuel cell composite anode based on phase field method

    NASA Astrophysics Data System (ADS)

    Jiao, Zhenjun; Shikazono, Naoki

    2016-02-01

    It is known that the reduction process influences the initial performances and durability of nickel-yttria-stabilized zirconia composite anode of the solid oxide fuel cell. In the present study, the reduction process of nickel-yttria stabilized zirconia composite anode is simulated based on the phase field method. An three-dimensional reconstructed microstructure of nickel oxide-yttria stabilized zirconia composite obtained by focused ion beam-scanning electron microscopy is used as the initial microstructure for the simulation. Both reduction of nickel oxide and nickel sintering mechanisms are considered in the model. The reduction rates of nickel oxide at different interfaces are defined based on the literature data. Simulation results are qualitatively compared to the experimental anode microstructures with different reduction temperatures.

  9. Reduction of body fat and improved lipid profile associated with daily consumption of a Puer tea extract in a hyperlipidemic population: a randomized placebo-controlled trial

    PubMed Central

    Jensen, Gitte S; Beaman, Joni L; He, Yi; Guo, Zhixin; Sun, Henry

    2016-01-01

    Objective The goal for this study was to evaluate the effects of daily consumption of Puer tea extract (PTE) on body weight, body-fat composition, and lipid profile in a non-Asian population in the absence of dietary restrictions. Materials and methods A randomized, double-blind, placebo-controlled study design was used. A total of 59 overweight or mildly obese subjects were enrolled upon screening to confirm fasting cholesterol level at or above 220 mg/dL (5.7 mmol/dL). After giving informed consent, subjects were randomized to consume PTE (3 g/day) or placebo for 20 weeks. At baseline and at 4-week intervals, blood lipids, C-reactive protein, and fasting blood glucose were evaluated. A dual-energy X-ray absorptiometry scan was performed at baseline and at study exit to evaluate changes to body composition. Appetite and physical and mental energy were scored at each visit using visual analog scales (0–100). Results Consumption of PTE was associated with statistically significant weight loss when compared to placebo (P<0.05). Fat loss was seen for arms, legs, and the gynoid region (hip/belly), as well as for total fat mass. The fat reduction reached significance on within-group analysis, but did not reach between-group significance. Consumption of PTE was associated with improvements to lipid profile, including a mild reduction in cholesterol and the cholesterol:high-density lipoprotein ratio after only 4 weeks, as well as a reduction in triglycerides and very small-density lipoproteins, where average blood levels reached normal range at 8 weeks and remained within normal range for the duration of the study (P<0.08). No significant changes between the PTE group and the placebo group were seen for fasting glucose or C-reactive protein. A transient reduction in appetite was seen in the PTE group when compared to placebo (P<0.1). Conclusion The results from this clinical study showed that the daily consumption of PTE was associated with significant weight loss

  10. Pyrolyzed binuclear-cobalt-phthalocyanine as electrocatalyst for oxygen reduction reaction in microbial fuel cells.

    PubMed

    Li, Baitao; Wang, Mian; Zhou, Xiuxiu; Wang, Xiujun; Liu, Bingchuan; Li, Baikun

    2015-10-01

    A novel platinum (Pt)-free cathodic materials binuclear-cobalt-phthalocyanine (Bi-CoPc) pyrolyzed at different temperatures (300-1000 °C) were examined as the oxygen reduction reaction (ORR) catalysts, and compared with unpyrolyzed Bi-CoPc/C and Pt cathode in single chamber microbial fuel cells (SCMFCs). The results showed that the pyrolysis process increased the nitrogen abundance on Bi-CoPc and changed the nitrogen types. The Bi-CoPc pyrolyzed at 800 °C contained a significant amount of pyrrolic-N, and exhibited a high electrochemical catalytic activity. The power density and current density increased with temperature: Bi-CoPc/C-800 > Bi-CoPc/C-1000 > Bi-CoPc/C-600 > Bi-CoPc/C-300 > Bi-CoPc/C. The SCMFC with Bi-CoPc/C-800 cathode had a maximum power density of 604 mW m(-2). The low cost Bi-CoPc compounds developed in this study showed a potential in air-breathing MFC systems, with the proper pyrolysis temperature being chosen. PMID:26142820

  11. PTFE effect on the electrocatalysis of the oxygen reduction reaction in membraneless microbial fuel cells.

    PubMed

    Guerrini, Edoardo; Grattieri, Matteo; Faggianelli, Alessio; Cristiani, Pierangela; Trasatti, Stefano

    2015-12-01

    Influence of PTFE in the external Gas Diffusion Layer (GDL) of open-air cathodes applied to membraneless microbial fuel cells (MFCs) is investigated in this work. Electrochemical measurements on cathodes with different PTFE contents (200%, 100%, 80% and 60%) were carried out to characterize cathodic oxygen reduction reaction, to study the reaction kinetics. It is demonstrated that ORR is not under diffusion-limiting conditions in the tested systems. Based on cyclic voltammetry, an increase of the cathodic electrochemical active area took place with the decrease of PTFE content. This was not directly related to MFC productivity, but to the cathode wettability and the biocathode development. Low electrodic interface resistances (from 1 to 1.5 Ω at the start, to near 0.1 Ω at day 61) indicated a negligible ohmic drop. A decrease of the Tafel slopes from 120 to 80 mV during productive periods of MFCs followed the biological activity in the whole MFC system. A high PTFE content in the cathode showed a detrimental effect on the MFC productivity, acting as an inhibitor of ORR electrocatalysis in the triple contact zone. PMID:26045153

  12. OPTIMIZED FUEL INJECTOR DESIGN FOR MAXIMUM IN-FURNACE NOx REDUCTION AND MINIMUM UNBURNED CARBON

    SciTech Connect

    SAROFIM, A F; LISAUSKAS, R; RILEY, D; EDDINGS, E G; BROUWER, J; KLEWICKI, J P; DAVIS, K A; BOCKELIE, M J; HEAP, M P; PERSHING, D

    1998-01-01

    Reaction Engineering International (REI) has established a project team of experts to develop a technology for combustion systems which will minimize NO x emissions and minimize carbon in the fly ash. This much need technology will allow users to meet environmental compliance and produce a saleable by-product. This study is concerned with the NO x control technology of choice for pulverized coal fired boilers,"in-furnace NOx control," which includes: staged low-NOx burners, reburning, selective non-catalytic reduction (SNCR) and hybrid approaches (e.g., reburning with SNCR). The program has two primary objectives: 1) To improve the performance of "in-furnace" NOx control, processes. 2) To devise new, or improve existing, approaches for maximum "in-furnace" NOx control and minimum unburned carbon. The program involves: 1) fundamental studies at laboratory- and bench-scale to define NO reduction mechanisms in flames and reburning jets; 2) laboratory experiments and computer modeling to improve our two-phase mixing predictive capability; 3) evaluation of commercial low-NOx burner fuel injectors to develop improved designs, and 4) demonstration of coal injectors for reburning and low-NOx burners at commercial scale. The specific objectives of the two-phase program are to: 1 Conduct research to better understand the interaction of heterogeneous chemistry and two phase mixing on NO reduction processes in pulverized coal combustion. 2 Improve our ability to predict combusting coal jets by verifying two phase mixing models under conditions that simulate the near field of low-NOx burners. 3 Determine the limits on NO control by in-furnace NOx control technologies as a function of furnace design and coal type. 5 Develop and demonstrate improved coal injector designs for commercial low-NOx burners and coal reburning systems. 6 Modify the char burnout model in REI's coal

  13. The coprocessing of fossil fuels and biomass for CO{sub 2} emission reduction in the transportation sector

    SciTech Connect

    Steinberg, M.; Dong, Yuanji; Borgwardt, R.H.

    1993-10-01

    Research is underway to evaluate the Hydrocarb process for conversion of carbonaceous raw material to clean carbon and methanol products. These products are valuable in the market either as fuel or as chemical commodities. As fuel, methanol and carbon can be used economically, either independently or in slurry form, in efficient heat energies (turbines and internal combustion engines) for both mobile and stationary single and combined cycle power plants. When considering CO{sub 2} emission control in the utilization of fossil fuels, the copressing of those fossil fuels with biomass (which may include, wood, municipal solid waste and sewage sludge) is a viable mitigation approach. By coprocessing both types of feedstock to produce methanol and carbon while sequestering all or part of the carbon, a significant net CO{sub 2} reduction is achieved if the methanol is substituted for petroleum fuels in the transportation sector. The Hydrocarb process has the potential, if the R&D objectives are achieved, to produce alternative transportation fuel from indigenous resources at lower cost than any other biomass conversion process. These comparisons suggest the resulting fuel can significantly displace gasoline at a competitive price while mitigating CO{sub 2} emissions and reducing ozone and other toxics in urban atmospheres.

  14. Effects of idle reduction technologies on real world fuel use and exhaust emissions of idling long-haul trucks.

    PubMed

    Frey, H Christopher; Kuo, Po-Yao; Villa, Charles

    2009-09-01

    Idling long-haul freight tucks may consume nearly one billion gallons of diesel fuel per year in the U.S. There is a need for real-world data by which to quantify avoided fuel use and emissions attributable to idle reduction techniques of auxiliary power units (APUs) and shore-power (SP). Field data were obtained from 20 APU-equipped and SP-compatible trucks observed during 2.8 million miles of travel in 42 states. Base engine fuel use and emission rates varied depending on ambient temperature. APU and SP energy use and emission rates varied depending on electrical load. APUs reduced idling fuel use and CO2 emissions for single and team drivers by 22 and 5% annually, respectively. SP offers greater reductions in energy use of 48% for single drivers, as well as in emissions, except for SO2. APUs were cost-effective for single drivers with a large number of APU usage hours per year, but not for team drivers or for single drivers with low APU utilization rates. The findings support more accurate assessments of avoided fuel use and emissions, and recommendations to encourage greater APU utilization by single drivers and to further develop infrastructure for SP. PMID:19764263

  15. Phosphorus-doped carbon nanotubes supported low Pt loading catalyst for the oxygen reduction reaction in acidic fuel cells

    NASA Astrophysics Data System (ADS)

    Liu, Ziwu; Shi, Qianqian; Zhang, Rufan; Wang, Quande; Kang, Guojun; Peng, Feng

    2014-12-01

    To develop low-cost and efficient cathode electrocatalysts for fuel cells in acidic media, phosphorus-doped carbon nanotubes (P-CNTs) supported low Pt loading catalyst (0.85% Pt) is designed. The as-prepared Pt/P-CNTs exhibit significantly enhanced electrocatalytic oxygen reduction reaction (ORR) activity and long-term stability due to the stronger interaction between Pt and P-CNTs, which is proven by X-ray photoelectron spectroscopic analysis and density functional theory calculations. Moreover, the as-prepared Pt/P-CNTs also display much better tolerance to methanol crossover effects, showing a good potential application for future proton exchange membrane fuel cell devices.

  16. Reduction of the spent nuclear fuel of a VVER-1000 reactor by lithium in a lithium chloride melt

    NASA Astrophysics Data System (ADS)

    Bychkov, A. V.; Ishunin, V. S.; Kormilitsyn, M. V.

    2010-08-01

    Researchers at FGUP GNTs RF NIIAR performed a series of experiments on the lithium reduction of the spent nuclear fuel (SNF) of a VVER-1000 reactor to a metal in a lithium chloride melt. The depletion of the nuclear fuel taken before experiments is about 30000 (MW day)/t, and the cooling time is 5 years. The experiments are performed on 5.8-kg samples of a prepared SNF powder. Data are obtained on a decrease in the heat release, the specific activity of the processed powder, and the distribution of actinides and the main fission products between a salt phase and a reduced SNF powder.

  17. Greenhouse Gas and Criteria Air Pollutant Emission Reductions from Forest Fuel Treatment Projects in Placer County, California

    NASA Astrophysics Data System (ADS)

    Saah, D. S.; Moritz, M.; Ganz, D. J.; Stine, P. A.; Moody, T.

    2010-12-01

    Years of successful fire suppression activities have left forests unnaturally dense, overstocked, and with high hazardous fuel loads. Wildfires, particularly those of high severity, may dramatically reduce carbon stocks and convert forested lands from carbon sinks to decades-long carbon sources . Forest resource managers are currently pursuing fuels reduction and mitigation strategies to reduce wildfire risk and maintain carbon stocks. These projects include selective thinning and removal of trees and brush to return forest ecosystems to more natural stocking levels, resulting in a more fire-resilient forest that in theory would retain higher carry capacity for standing above ground carbon. Resource managers are exploring the possibility of supporting these local forest management projects by offering greenhouse gas (GHG) offsets to project developers that require GHG emissions mitigation. Using robust field data, this research project modeled three types of carbon benefits that could be realized from forest management: 1. Fuels treatments in the study area were shown to reduce the GHG and Criteria Air Pollutant emissions from wildfires by decreasing the probability, extent, and severity of fires and the corresponding loss in forest carbon stocks; 2. Biomass utilization from fuel treatment was shown to reduce GHG and Criteria Air Pollutant emissions over the duration of the fuels treatment project compared to fossil fuel energy. 3. Management and thinning of forests in order to stimulate growth, resulting in more rapid uptake of atmospheric carbon and approaching a carbon carrying capacity stored in a forest ecosystem under prevailing environmental conditions and natural disturbance regimes.

  18. Analysis on fuel economy improvement and exhaust emission reduction in a two-stroke engine by using an exhaust valve

    SciTech Connect

    Asai, Masahiro; Kurosaki, Takaharu; Okada, Kazunori

    1995-12-31

    A timing controlled auto-ignition name ``AR combustion`` could improve irregular combustion in the part load operation of conventional two-stroke engines. Their previous papers have suggested its idea and the drastic improvements in fuel consumption and HC emission proven through a bench experiments. This time, form a concept that improvements of a two-stroke engine should be done maintaining its original advantages, an AR combustion engine was developed by using a simple exhaust valve and maintaining engine`s original power output. This engine was mounted on a motorcycle and experimented in the ``Dakar rally``. As the results, good fuel economies exceeding a four-stroke rally model, excellent driveability and durability were proven, because of the improvement in the combustion and engine`s potential for the downsizing. The AR combustion engine, consequently, has good prospects for the practical use.

  19. Peak-Seeking Control For Reduced Fuel Consumption: Flight-Test Results For The Full-Scale Advanced Systems Testbed FA-18 Airplane

    NASA Technical Reports Server (NTRS)

    Brown, Nelson

    2013-01-01

    A peak-seeking control algorithm for real-time trim optimization for reduced fuel consumption has been developed by researchers at the National Aeronautics and Space Administration (NASA) Dryden Flight Research Center to address the goals of the NASA Environmentally Responsible Aviation project to reduce fuel burn and emissions. The peak-seeking control algorithm is based on a steepest-descent algorithm using a time-varying Kalman filter to estimate the gradient of a performance function of fuel flow versus control surface positions. In real-time operation, deflections of symmetric ailerons, trailing-edge flaps, and leading-edge flaps of an F/A-18 airplane are used for optimization of fuel flow. Results from six research flights are presented herein. The optimization algorithm found a trim configuration that required approximately 3 percent less fuel flow than the baseline trim at the same flight condition. This presentation also focuses on the design of the flight experiment and the practical challenges of conducting the experiment.

  20. Influence of reduction conditions on electrical properties of NiO-zirconia composites for solid oxide fuel cell electrode

    NASA Astrophysics Data System (ADS)

    Orui, Himeko; Nozawa, Kazuhiko; Arai, Hajime; Kanno, Ryoji

    2015-08-01

    The electrical properties of nickel-zirconia cermets as the anode material for solid oxide fuel cells (SOFCs) were studied for Sc2O3-Al2O3-stabilized ZrO2 (SASZ), together with conventional Y2O3-stabilized ZrO2 (YSZ). The reduction behavior of the cermets in terms of achieving better electrical conductivity was examined under constant temperature ramp rate (CTR) and constant temperature (CT) conditions. The reduction process and electrical conduction thus obtained were affected by the NiO particle size and porosity, and the zirconia composition of the starting NiO-zirconia composite material. All the NiO-zirconia anodes examined in this study exhibited high conductivity after reduction at a CT of 800 °C. The CTR condition resulted in lower electrical conductivity for the Ni-zirconia cermet. In particular, NiO-SASZ using coarse NiO powder exhibited only ionic conduction with a low electronic contribution, which was due to the absence of nickel-nickel percolation. Thermogravimetric analysis of the NiO reduction indicated that NiO-SASZ and NiO-YSZ had different reduction mechanism which might correspond to the interaction between NiO and zirconia and the long-term stability of these cermets. A kinetic analysis of the NiO reduction process revealed that fast and constant nucleation during the initial stage of reduction is important for the construction of nickel-nickel connections in the cermets.

  1. A micro-nano porous oxide hybrid for efficient oxygen reduction in reduced-temperature solid oxide fuel cells

    PubMed Central

    Da Han; Liu, Xuejiao; Zeng, Fanrong; Qian, Jiqin; Wu, Tianzhi; Zhan, Zhongliang

    2012-01-01

    Tremendous efforts to develop high-efficiency reduced-temperature (≤ 600°C) solid oxide fuel cells are motivated by their potentials for reduced materials cost, less engineering challenge, and better performance durability. A key obstacle to such fuel cells arises from sluggish oxygen reduction reaction kinetics on the cathodes. Here we reported that an oxide hybrid, featuring a nanoporous Sm0.5Sr0.5CoO3−δ (SSC) catalyst coating bonded onto the internal surface of a high-porosity La0.9Sr0.1Ga0.8Mg0.2O3−δ (LSGM) backbone, exhibited superior catalytic activity for oxygen reduction reactions and thereby yielded low interfacial resistances in air, e.g., 0.021 Ω cm2 at 650°C and 0.043 Ω cm2 at 600°C. We further demonstrated that such a micro-nano porous hybrid, adopted as the cathode in a thin LSGM electrolyte fuel cell, produced impressive power densities of 2.02 W cm−2 at 650°C and 1.46 W cm−2 at 600°C when operated on humidified hydrogen fuel and air oxidant. PMID:22708057

  2. Challenges in sodium intake reduction and meal consumption patterns among participants with metabolic syndrome in a dietary trial

    PubMed Central

    2013-01-01

    Background Dietary guidelines suggest limiting daily sodium intake to <2,300 mg for the general population, and <1,500 mg/d for those with certain cardiovascular risk factors. Despite these recommendations, few Americans are able to achieve this goal. Identifying challenges in meeting these guidelines is integral for successful compliance. This analysis examined patterns and amount of daily sodium intake among participants with metabolic syndrome enrolled in a one-year dietary intervention study. Methods Two hundred forty participants with metabolic syndrome enrolled in a dietary intervention trial to lose weight and improve dietary quality. Three 24-hour dietary recalls were collected at each visit which provided meal patterns and nutrient data, including sodium intake. A secondary data analysis was conducted to examine sodium consumption patterns at baseline and at one-year study visits. Sodium consumption patterns over time were examined using linear mixed models. Results The percentage of meals reported eaten in the home at both baseline and one-year follow-up was approximately 69%. Follow-up for the one-year dietary intervention revealed that the participants who consumed sodium greater than 2,300 mg/d declined from 75% (at baseline) to 59%, and those that consumed higher than 1,500 mg/d declined from 96% (at baseline) to 85%. Average sodium intake decreased from 2,994 mg at baseline to 2,558 mg at one-year (P < 0.001), and the sodium potassium ratio also decreased from 1.211 to 1.047 (P < 0.001). Sodium intake per meal varied significantly by meal type, location, and weekday, with higher intake at dinner, in restaurants, and on weekends. At-home lunch and dinner sodium intake decreased (P < 0.05), while dinner sodium intake at restaurant/fast food chains increased from baseline to one-year (P < 0.05). Conclusion Sodium intake for the majority of participants exceeded the recommended dietary guidelines. Findings support actions that

  3. Can switching fuels save water? A life cycle quantification of freshwater consumption for Texas coal- and natural gas-fired electricity

    NASA Astrophysics Data System (ADS)

    Grubert, Emily A.; Beach, Fred C.; Webber, Michael E.

    2012-12-01

    Thermal electricity generation is a major consumer of freshwater for cooling, fuel extraction and air emissions controls, but the life cycle water impacts of different fossil fuel cycles are not well understood. Much of the existing literature relies on decades-old estimates for water intensity, particularly regarding water consumed for fuel extraction. This work uses contemporary data from specific resource basins and power plants in Texas to evaluate water intensity at three major stages of coal and natural gas fuel cycles: fuel extraction, power plant cooling and power plant emissions controls. In particular, the water intensity of fuel extraction is quantified for Texas lignite, conventional natural gas and 11 unconventional natural gas basins in Texas, including major second-order impacts associated with multi-stage hydraulic fracturing. Despite the rise of this water-intensive natural gas extraction method, natural gas extraction appears to consume less freshwater than coal per unit of energy extracted in Texas because of the high water intensity of Texas lignite extraction. This work uses new resource basin and power plant level water intensity data to estimate the potential effects of coal to natural gas fuel switching in Texas’ power sector, a shift under consideration due to potential environmental benefits and very low natural gas prices. Replacing Texas’ coal-fired power plants with natural gas combined cycle plants (NGCCs) would reduce annual freshwater consumption in the state by an estimated 53 billion gallons per year, or 60% of Texas coal power’s water footprint, largely due to the higher efficiency of NGCCs.

  4. EVALUATION OF TIRE-DERIVED FUEL FOR USE IN NITROGEN OXIDE REDUCTION BY REBURNING

    EPA Science Inventory

    Tire-derived fuel (TDF) was tested in a small-scale (44 kW or 150,000 Btu/hr) combustor to determine its feasibility as a fuel for use in reburning for control of nitrogen oxide (NO). TDF was gravity-fed into upward flowing combustion gases from a primary natural gas flame doped ...

  5. 75 FR 64243 - Umatilla National Forest, Walla Walla Ranger District; Oregon Tollgate Fuels Reduction Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-19

    ...) trees and dead and down material. These activities would occur adjacent to private property and FR 64..., power transmission lines, and communication equipment) is interspersed throughout the WUI. Oregon State... change in fire behavior within the Tollgate WUI by reducing fuels and creating strategic fuel...

  6. COPROCESSING OF FOSSIL FUELS AND BIOMASS FOR CO2 EMISSION REDUCTION IN THE TRANSPORTATION SECTOR

    EPA Science Inventory

    The paper discusses an evaluation of the Hydrocarb process for conversion of carbonaceous raw material to clean carbon and methanol products. hese products are valuable in the market either as fuel or as chemical commodities. s fuel, methanol and carbon can be used economically, ...

  7. 77 FR 33158 - Plumas National Forest, California, Sugarloaf Hazardous Fuels Reduction Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-05

    ... communities through: fuels treatments; group selections (GS); area and variable density thinning from below... Sugarloaf Project area, because stand densities are unnaturally overcrowded and dominated by shade-tolerant... acres of defensible fuel profile zones (DFPZs) using 763 acres of variable density and 229 acres...

  8. Plutonium Consumption Program, CANDU Reactor Project: Feasibility of BNFP Site as MOX Fuel Supply Facility. Final report

    SciTech Connect

    1995-06-30

    An evaluation was made of the technical feasibility, cost, and schedule for converting the existing unused Barnwell Nuclear Fuel Facility (BNFP) into a Mixed Oxide (MOX) CANDU fuel fabrication plant for disposition of excess weapons plutonium. This MOX fuel would be transported to Ontario where it would generate electricity in the Bruce CANDU reactors. Because CANDU MOX fuel operates at lower thermal load than natural uranium fuel, the MOX program can be licensed by AECB within 4.5 years, and actual Pu disposition in the Bruce reactors can begin in 2001. Ontario Hydro will have to be involved in the entire program. Cost is compared between BNFP and FMEF at Hanford for converting to a CANDU MOX facility.

  9. Nonproliferation and safeguards aspects of fuel cycle programs in reduction of excess separated plutonium and high-enriched uranium

    SciTech Connect

    Persiani, P.J.

    1995-06-01

    The purpose of this preliminary investigation is to explore alternatives and strategies aimed at the gradual reduction of the excess inventories of separated plutonium and high-enriched uranium (HEU) in the civilian nuclear power industry. The study attempts to establish a technical and economic basis to assist in the formation of alternative approaches consistent with nonproliferation and safeguards concerns. Reference annual mass flows and inventories for a representative 1,400 Mwe Pressurized Water Reactor (PWR) fuel cycle have been investigated for three cases: the 100 percent uranium oxide UO{sub 2} fuel loading once through cycle, and the 33 percent mixed oxide MOX loading configuration for a first and second plutonium recycle. The analysis addresses fuel cycle developments; plutonium and uranium inventory and flow balances; nuclear fuel processing operations; UO{sub 2} once-through and MOX first and second recycles; and the economic incentives to draw-down the excess separated plutonium stores. The preliminary analysis explores several options in reducing the excess separated plutonium arisings and HEU, and the consequences of the interacting synergistic effects between fuel cycle processes and isotopic signatures of nuclear materials on nonproliferation and safeguards policy assessments.

  10. ERBS fuel addendum: Pollution reduction technology program small jet aircraft engines, phase 3

    NASA Technical Reports Server (NTRS)

    Bruce, T. W.; Davis, F. G.; Kuhn, T. E.; Mongia, H. C.

    1982-01-01

    A Model TFE731-2 engine with a low emission, variable geometry combustion system was tested to compare the effects of operating the engine on Commercial Jet-A aviation turbine fuel and experimental referee broad specification (ERBS) fuels. Low power emission levels were essentially identical while the high power NOx emission indexes were approximately 15% lower with the EBRS fuel. The exhaust smoke number was approximately 50% higher with ERBS at the takeoff thrust setting; however, both values were still below the EPA limit of 40 for the Model TFE731 engine. Primary zone liner wall temperature ran an average of 25 K higher with ERBS fuel than with Jet-A. The possible adoption of broadened proprties fuels for gas turbine applications is suggested.

  11. Computer program for prediction of fuel consumption statistical data for an upper stage three-axes stabilized on-off control system

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A FORTRAN coded computer program and method to predict the reaction control fuel consumption statistics for a three axis stabilized rocket vehicle upper stage is described. A Monte Carlo approach is used which is more efficient by using closed form estimates of impulses. The effects of rocket motor thrust misalignment, static unbalance, aerodynamic disturbances, and deviations in trajectory, mass properties and control system characteristics are included. This routine can be applied to many types of on-off reaction controlled vehicles. The pseudorandom number generation and statistical analyses subroutines including the output histograms can be used for other Monte Carlo analyses problems.

  12. Monthly estimates of carbon dioxide emissions from fossil-fuel consumption in Brazil during the late 1990s and early 2000s

    SciTech Connect

    Losey, London M; Andres, Robert Joseph; Marland, Gregg

    2006-12-01

    Detailed understanding of global carbon cycling requires estimates of CO2 emissions on temporal and spatial scales finer than annual and country. This is the first attempt to derive such estimates for a large, developing, Southern Hemisphere country. Though data on energy use are not complete in terms of time and geography, there are enough data available on the sale or consumption of fuels in Brazil to reasonably approximate the temporal and spatial patterns of fuel use and CO2 emissions. Given the available data, a strong annual cycle in emissions from Brazil is not apparent. CO2 emissions are unevenly distributed within Brazil as the population density and level of development both vary widely.

  13. Carbon dioxide emissions from fossil fuel consumption and cement manufacture, 1751-1991; and an estimate of their isotopic composition and latitudinal distribution

    SciTech Connect

    Andres, R.J.; Marland, G.; Boden, T.; Bischof, S.

    1994-10-01

    This work briefly discusses four of the current research emphases at Oak Ridge National Laboratory regarding the emission of carbon dioxide (CO{sub 2}) from fossil fuel consumption, natural gas flaring and cement manufacture. These emphases include: (1) updating the 1950 to present time series of CO{sub 2} emissions from fossil fuel consumption and cement manufacture, (2) extending this time series back to 1751, (3) gridding the data at 1{sup 0} by 1{sup 0} resolution, and (4) estimating the isotopic signature of these emissions. In 1991, global emissions of CO{sub 2} from fossil fuel and cement increased 1.5% over 1990 levels to 6188 {times} 10{sup 6} metric tonnes C. The Kuwaiti oil fires can account for all of the increase. Recently published energy data (Etemad et al., 1991) allow extension of the CO emissions time series back to 1751. Preliminary examination shows good agreement with two other, but shorter, energy time series. A latitudinal distribution of carbon emissions is being completed. A southward shift in the major mass of CO{sub 2} emissions is occurring from European-North American latitudes towards central-southeast Asian latitudes, reflecting the growth of population and industrialization at these lower latitudes. The carbon isotopic signature of these emissions has been re-examined. The emissions of the last two decades are approximately 1{per_thousand} lighter than previously reported (Tans, 1981). This lightening of the emissions signature is due to fossil fuel gases and liquids, including a revision of their {delta}{sup 13}C isotopic signature and an increased production rate.

  14. Reduction of fuel side costs due to biomass co-combustion.

    PubMed

    Wils, Andrea; Calmano, Wolfgang; Dettmann, Peter; Kaltschmitt, Martin; Ecke, Holger

    2012-03-15

    The feasibility and influence of co-combustion of woody biomass on the fuel side costs is discussed for three hard coal power plants located in Berlin, Germany. Fuel side costs are defined as the costs resulting from flue gas cleaning and by-products. To have reliable data, co-firing tests were conducted in two power plants (i.e., slag tap furnace and circulating fluidising bed combustion). The amount of wood which was co-fired varied at levels below 11% of the fuel heat input. Wood chips originating from landscape management were used. The analyses show that co-combustion of woody biomass can lower the fuel side costs and that the co-combustion at a level below 10% of the thermal capacity is technically feasible without major problems. Furthermore, a flexible spreadsheet tool was developed for the calculation of fuel side costs and suggestions for operational improvements were made. For example, the adaptation of the Ca/S ratio (mass ratio of calcium in limestone to sulphur in the fuel) in one plant could reduce the fuel side costs up to 135 k€ yr(-1) (0.09 €M Wh(-1)). PMID:21514049

  15. 76 FR 70955 - Helena Nation Forest: Dalton Mountain Forest Restoration & Fuels Reduction Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-16

    ... fuels arrangement; enhance composition of aspen, whitebark pine, and ponderosa pine species; modify fire... composition of aspen, whitebark pine, and ponderosa pine species and their habitats. Modify fire behavior...

  16. Solid Oxide Fuel Cell Cathodes. Unraveling the Relationship Between Structure, Surface Chemistry and Oxygen Reduction

    SciTech Connect

    Gopalan, Srikanth

    2013-03-31

    In this work we have considered oxygen reduction reaction on LSM and LSCF cathode materials. In particular we have used various spectroscopic techniques to explore the surface composition, transition metal oxidation state, and the bonding environment of oxygen to understand the changes that occur to the surface during the oxygen reduction process. In a parallel study we have employed patterned cathodes of both LSM and LSCF cathodes to extract transport and kinetic parameters associated with the oxygen reduction process.

  17. Highly efficient visible light photocatalytic reduction of CO2 to hydrocarbon fuels by Cu-nanoparticle decorated graphene oxide.

    PubMed

    Shown, Indrajit; Hsu, Hsin-Cheng; Chang, Yu-Chung; Lin, Chang-Hui; Roy, Pradip Kumar; Ganguly, Abhijit; Wang, Chen-Hao; Chang, Jan-Kai; Wu, Chih-I; Chen, Li-Chyong; Chen, Kuei-Hsien

    2014-11-12

    The production of renewable solar fuel through CO2 photoreduction, namely artificial photosynthesis, has gained tremendous attention in recent times due to the limited availability of fossil-fuel resources and global climate change caused by rising anthropogenic CO2 in the atmosphere. In this study, graphene oxide (GO) decorated with copper nanoparticles (Cu-NPs), hereafter referred to as Cu/GO, has been used to enhance photocatalytic CO2 reduction under visible-light. A rapid one-pot microwave process was used to prepare the Cu/GO hybrids with various Cu contents. The attributes of metallic copper nanoparticles (∼4-5 nm in size) in the GO hybrid are shown to significantly enhance the photocatalytic activity of GO, primarily through the suppression of electron-hole pair recombination, further reduction of GO's bandgap, and modification of its work function. X-ray photoemission spectroscopy studies indicate a charge transfer from GO to Cu. A strong interaction is observed between the metal content of the Cu/GO hybrids and the rates of formation and selectivity of the products. A factor of greater than 60 times enhancement in CO2 to fuel catalytic efficiency has been demonstrated using Cu/GO-2 (10 wt % Cu) compared with that using pristine GO. PMID:25354234

  18. H2O2 detection analysis of oxygen reduction reaction on cathode and anode catalysts for polymer electrolyte fuel cells

    NASA Astrophysics Data System (ADS)

    Kishi, Akira; Shironita, Sayoko; Umeda, Minoru

    2012-01-01

    The generation percentage of H2O2 during oxygen reduction reaction (ORR) at practical powder electrocatalysts was evaluated using a scanning electrochemical microscope (SECM). We employed a porous microelectrode that contains electrocatalysts, namely, Pt/C, Pt-Co/C, and Pt-Ru/C as the oxygen reduction electrode of the SECM, and the Pt microelectrode was used as the H2O2 detector. First, the H2O2 generation amount at Pt/Cs was measured by changing the Pt loading amount. A Pt/C with a higher Pt loading has a higher ORR activity and generates a larger amount of H2O2. However, the percentage of H2O2 generated with respect to the ORR is the same regardless of the Pt loading amount. Next, H2O2 generation is markedly suppressed at the Pt-Co/C and Pt-Ru/C in the potential ranges of practical fuel cell cathode and anode, respectively. This explains that the Pt-Co/C is effective when used as a cathode, and the anode Pt-Ru/C enables the reduction of the H2O2 generation even if O2 crossleak occurs in the practical polymer electrolyte fuel cell.

  19. NOx reduction in diesel fuel flames by additions of water and CO{sub 2}

    SciTech Connect

    Li, S.C.

    1997-12-31

    Natural gas has the highest heating value per unit mass (50.1 MJ/kg, LHV) of any of the hydrocarbon fuels (e.g., butane, liquid diesel fuel, gasoline, etc.). Since it has the lowest carbon content per unit mass, combustion of natural gas produces much less carbon dioxide, soot particles, and oxide of nitrogen than combustion of liquid diesel fuel. In view of anticipated strengthening of regulations on pollutant emissions from diesel engines, alternative fuels, such as compressed natural gas (CNG) and liquefied natural gas (LNG) have been experimentally introduced to replace the traditional diesel fuels in heavy-duty trucks, transit buses, off-road vehicles, locomotives, and stationary engines. To help in applying natural gas in Diesel engines and increasing combustion efficiency, the emphasis of the present paper is placed on the detailed flame chemistry of methane-air combustion. The present work is the continued effort in finding better methods to reduce NO{sub x}. The goal is to identify a reliable chemical reaction mechanism for natural gas in both premixed and diffusion flames and to establish a systematic reduced mechanism which may be useful for large-scale numerical modeling of combustion behavior in natural gas engines.

  20. Forest Fuel Reduction and Wildfire Effects on Runoff and Evapotranspiration in Sierra Nevada Mixed-Conifer Forest

    NASA Astrophysics Data System (ADS)

    Saksa, P. C.; Bales, R. C.; Conklin, M. H.

    2015-12-01

    Large, high-intensity wildfire risk in the western United States is growing, fueled by increasing vegetation density from a century of fire suppression and climatic shifts resulting in extended dry seasons. Strategically Placed Landscape Treatments (SPLATs) are a fuel reduction method designed to reduce fire risk on the entire landscape by treating only a fraction of the area. During 2011 and 2012, SPLATs were implemented in the mixed-conifer zone of the Tahoe (Last Chance study area, American River Basin) and Sierra (Sugar Pine study area, Merced River Basin) National Forests. Wildfire events were then simulated for both treated and untreated conditions. We integrated the vegetation changes with the Regional Hydro-Ecological Simulation System (RHESSys) to project impacts of fuel treatments and wildfire on runoff and evapotranspiration for the period of observed data, water years 2010-2013. Results from the model simulations show that vegetation treatments in the Last Chance study area, which removed 8.0% of the total biomass by treating 25% of the area, increased mean annual runoff by 12.0% and decreased mean annual evapotranspiration by 4.1%. Vegetation treatments in the Sugar Pine study area, which removed 7.5% of the total biomass by treating 33% of the area, increased runoff by 2.7% and decreased ET by 0.5%. Compared to pre-treatment conditions, wildfire simulations in Last Chance reduced total biomass by 38-50% when fuel treatments were not applied, resulting in a 55-67% runoff increase and a 19-23% evapotranspiration decrease. In Sugar Pine, fire simulation reduced biomass 39-43%, increasing runoff and decreasing ET by 13-15% and 1.8-2.7% respectively. Applying the same magnitude of biomass reductions equally over the entire watershed, in contrast to the localized areas of vegetation reductions due to treatment or fire, resulted in smaller impacts on runoff and evapotranspiration rates. Vegetation effects on hydrologic fluxes are greater in Last Chance than

  1. Reduction of worldwide plutonium inventories using conventional reactors and advanced fuels: A systems study

    SciTech Connect

    Krakowski, R.A.; Bathke, C.G.; Chodak, P. III

    1997-09-01

    The potential for reducing plutonium inventories in the civilian nuclear fuel cycle through recycle in LWRs of a variety of mixed-oxide forms is examined by means of a cost-based plutonium-flow systems model that includes an approximate measure of proliferation risk. The impact of plutonium recycle in a number of forms is examined, including the introduction of nonfertile fuels into conventional (LWR) reactors to reduce net plutonium generation, to increase plutonium burnup, and to reduce exo-reactor plutonium inventories.

  2. Microchannel Distillation of JP-8 Jet Fuel for Sulfur Content Reduction

    SciTech Connect

    Zheng, Feng; Stenkamp, Victoria S.; TeGrotenhuis, Ward E.; Huang, Xiwen; King, David L.

    2006-09-16

    In microchannel based distillation processes, thin vapor and liquid films are contacted in small channels where mass transfer is diffusion-limited. The microchannel architecture enables improvements in distillation processes. A shorter height equivalent of a theoretical plate (HETP) and therefore a more compact distillation unit can be achieved. A microchannel distillation unit was used to produce a light fraction of JP-8 fuel with reduced sulfur content for use as feed to produce fuel-cell grade hydrogen. The HETP of the microchannel unit is discussed, as well as the effects of process conditions such as feed temperature, flow rate, and reflux ratio.

  3. Pollution reduction technology program for turboprop engines

    NASA Technical Reports Server (NTRS)

    Tomlinson, J. G.

    1977-01-01

    The reduction of CO, HC, and smoke emissions while maintaining acceptable NO(x) emissions without affecting fuel consumption, durability, maintainability, and safety was accomplished. Component combustor concept screening directed toward the demonstration of advanced combustor technology required to meet the EPA exhaust emissions standards for class P2 turboprop engines was covered. The combustion system for the Allison 501-D22A engine was used, and three combustor design concepts - reverse flow, prechamber, and staged fuel were evaluated.

  4. Consumption of a healthy dietary pattern results in significant reductions in C-reactive protein levels in adults: a meta-analysis.

    PubMed

    Neale, E P; Batterham, M J; Tapsell, L C

    2016-05-01

    Consumption of healthy dietary patterns has been associated with reduced risk of cardiovascular disease and metabolic syndrome. Dietary intervention targets disease prevention, so studies increasingly use biomarkers of underlying inflammation and metabolic syndrome progression to examine the diet-health relationship. The extent to which these biomarkers contribute to the body of evidence on healthy dietary patterns is unknown. The aim of this meta-analysis was to determine the effect of healthy dietary patterns on biomarkers associated with adiposity, insulin resistance, and inflammation in adults. A systematic search of Scopus, PubMed, Web of Science, and Cochrane Central Register of Controlled Trials (all years to April 2015) was conducted. Inclusion criteria were randomized controlled trials; effects of dietary patterns assessed on C-reactive protein (CRP), total adiponectin, high-molecular-weight adiponectin, tumor necrosis factor-α, adiponectin:leptin, resistin, or retinol binding protein 4. Random effects meta-analyses were conducted to assess the weighted mean differences in change or final mean values for each outcome. Seventeen studies were included in the review. These reflected research on dietary patterns associated with the Mediterranean diet, Nordic diet, Tibetan diet, and the Dietary Approaches to Stop Hypertension diet. Consumption of a healthy dietary pattern was associated with significant reductions in CRP (weighted mean difference, -0.75 [-1.16, -0.35]; P = .0003). Non-significant changes were found for all other biomarkers. This analysis found evidence for favorable effects of healthy dietary patterns on CRP, with limited evidence for other biomarkers. Future research should include additional randomized controlled trials incorporating a greater range of dietary patterns and biomarkers. PMID:27101757

  5. REDUCTION OF USE OF PETROLEUM ENERGY RESOURCES BY CONVERSION OF WASTE COOKING OILS INTO DIESEL FUEL

    EPA Science Inventory

    This project has a dual objective of providing hands-on experience to undergraduate engineering students and producing biodiesel fuel from a used cooking oil feedstock. The project consists of three phases: Phase I - process development and construction of a pilot plant; Phase...

  6. COPROCESSING OF FOSSIL FUELS AND BIOMASS FOR CO2 EMISSION REDUCTION IN THE TRANSPORTATION SECTOR

    EPA Science Inventory

    The paper discusses an evaluation of the Hydrocarb process for conversion of carbonaceous raw material to clean carbon and methanol products. As fuel, methanol and carbon can be used economically, either independently or in slurry form, in efficient heat engines (turbines and int...

  7. Advanced Aerodynamic Technologies for Ground Vehicle Fuel Economy Improvement and Emission Reductions

    SciTech Connect

    Ricahrd Wood

    2007-01-15

    SOLUS-Solutions and Technologies LLC utilized the opportunity presented by the Department of Energy (DOE) Inventions and Innovations grant to successfully develop, market, and license two of the original three fuel and emissions saving aerodynamic trailer attachments for the trucking industry. Working independent of the grant and with SOLUS funding SOLUS also developed, marketed and licensed three additional fuel and emissions saving aerodynamic trailer attachments for the trucking industry. The five inventions include four inventions that are applicable to all heavy truck trailers and one invention specifically designed for van trailers with swing doors. The SOLUS inventions have been developed for use on all trailer types as well as light and medium trucks. SOLUS-Solutions and Technologies LLC has licensed the five inventions to Silver Eagle Manufacturing Company of Portland Oregon. Each trailer outfitted with the SOLUS inventions saves approximately 2,000 gallons of fuel every 100,000 miles, which prevents over 20 tons of CO2 from entering the atmosphere. If all applicable trailers used the technology, the country could save more than 4.0 billion gallons of diesel fuel, reduce emissions by 40 million tons and save 10.0 billion dollars annually.

  8. Cost-effectiveness of controlling emissions for various alternative-fuel vehicle types, with vehicle and fuel price subsidies estimated on the basis of monetary values of emission reductions

    SciTech Connect

    Wang, M.Q.

    1993-12-31

    Emission-control cost-effectiveness is estimated for ten alternative-fuel vehicle (AFV) types (i.e., vehicles fueled with reformulated gasoline, M85 flexible-fuel vehicles [FFVs], M100 FFVs, dedicated M85 vehicles, dedicated M100 vehicles, E85 FFVS, dual-fuel liquefied petroleum gas vehicles, dual-fuel compressed natural gas vehicles [CNGVs], dedicated CNGVs, and electric vehicles [EVs]). Given the assumptions made, CNGVs are found to be most cost-effective in controlling emissions and E85 FFVs to be least cost-effective, with the other vehicle types falling between these two. AFV cost-effectiveness is further calculated for various cases representing changes in costs of vehicles and fuels, AFV emission reductions, and baseline gasoline vehicle emissions, among other factors. Changes in these parameters can change cost-effectiveness dramatically. However, the rank of the ten AFV types according to their cost-effectiveness remains essentially unchanged. Based on assumed dollars-per-ton emission values and estimated AFV emission reductions, the per-vehicle monetary value of emission reductions is calculated for each AFV type. Calculated emission reduction values ranged from as little as $500 to as much as $40,000 per vehicle, depending on AFV type, dollar-per-ton emission values, and baseline gasoline vehicle emissions. Among the ten vehicle types, vehicles fueled with reformulated gasoline have the lowest per-vehicle value, while EVs have the highest per-vehicle value, reflecting the magnitude of emission reductions by these vehicle types. To translate the calculated per-vehicle emission reduction values to individual AFV users, AFV fuel or vehicle price subsidies are designed to be equal to AFV emission reduction values. The subsidies designed in this way are substantial. In fact, providing the subsidies to AFVs would change most AFV types from net cost increases to net cost decreases, relative to conventional gasoline vehicles.

  9. Polymer Electrolyte Fuel Cells Employing Heteropolyacids as Redox Mediators for Oxygen Reduction Reactions: Pt-Free Cathode Systems.

    PubMed

    Matsui, Toshiaki; Morikawa, Eri; Nakada, Shintaro; Okanishi, Takeou; Muroyama, Hiroki; Hirao, Yoshifumi; Takahashi, Tsuyoshi; Eguchi, Koichi

    2016-07-20

    In this study, the heteropolyacids of H3+xPVxMO12-xO40 (x = 0, 2, and 3) were applied as redox mediators for the oxygen reduction reaction in polymer electrolyte fuel cells, of which the cathode is free from the usage of noble metals such as Pt/C. In this system, the electrochemical reduction of heteropolyacid over the carbon cathode and the subsequent reoxidation of the partially reduced heteropolyacid by exposure to the dissolved oxygen in the regenerator are important processes for continuous power generation. Thus, the redox properties of catholytes containing these heteropolyacids were investigated in detail. The substitution quantity of V in the heteropolyacid affected the onset reduction potential as well as the reduction current density, resulting in a difference in cell performance. The chemical composition of heteropolyacid also had a significant impact on the reoxidation property. Among the three compounds, H6PV3Mo9O40 was the most suitable redox mediator. Furthermore, the pH of the catholyte was found to be the crucial factor in determining the reoxidation rate of partially reduced heteropolyacid as well as cell performance. PMID:27348019

  10. Electricity generation and bivalent copper reduction as a function of operation time and cathode electrode material in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Wu, Dan; Huang, Liping; Quan, Xie; Li Puma, Gianluca

    2016-03-01

    The performance of carbon rod (CR), titanium sheet (TS), stainless steel woven mesh (SSM) and copper sheet (CS) cathode materials are investigated in microbial fuel cells (MFCs) for simultaneous electricity generation and Cu(II) reduction, in multiple batch cycle operations. After 12 cycles, the MFC with CR exhibits 55% reduction in the maximum power density and 76% increase in Cu(II) removal. In contrast, the TS and SSM cathodes at cycle 12 show maximum power densities of 1.7 (TS) and 3.4 (SSM) times, and Cu(II) removal of 1.2 (TS) and 1.3 (SSM) times higher than those observed during the first cycle. Diffusional resistance in the TS and SSM cathodes is found to appreciably decrease over time due to the copper deposition. In contrast to CR, TS and SSM, the cathode made with CS is heavily corroded in the first cycle, exhibiting significant reduction in both the maximum power density and Cu(II) removal at cycle 2, after which the performance stabilizes. These results demonstrate that the initial deposition of copper on the cathodes of MFCs is crucial for efficient and continuous Cu(II) reduction and electricity generation over prolonged time. This effect is closely associated with the nature of the cathode material. Among the materials examined, the SSM is the most effective and inexpensive cathode for practical use in MFCs.

  11. Low-Emissions Burner Technology using Biomass-Derived Liquid Fuels

    SciTech Connect

    2010-07-01

    The University of Alabama will develop fuel-flexible, low-emissions burner technology for the metal processing industry that is capable of using biomass-derived liquid fuels, such as glycerin or fatty acids, as a substitute for natural gas. By replacing a fossil fuel with biomass fuels, this new burner will enable a reduction in energy consumption and greenhouse gas emissions and an increase in fuel flexibility.

  12. Thermal Energy Consumption in the Heat-Technology Production of Solid Composite Fuel From Low-Grade Raw Materials

    NASA Astrophysics Data System (ADS)

    Tabakaev, Roman; Astafev, Alexander; Kazakov, Alexander; Zavorin, Alexander

    2016-02-01

    An evaluation is made of the thermal energy consumed in the heat-technology production of solid composite fuel from low-grade organic raw materials. It is shown that the heat of decomposition of the organic mass and the combustion of the by-products of heat-technology may be sufficient to cover all the energy needs for processing peat, brown coal and wood chips. Producing solid composite fuel from sapropel requires external resources to compensate for part of the heat consumed. Calculations show that it is possible for the thermal processing of raw materials to proceed autothermally due to the heat of decomposition when the moisture content at the reactor inlet is limited: for peat it should be no more than 35%, 54% for brown coal, and 37% for wood chips. The low heat of decomposition of the sapropel organic mass means that its thermal processing cannot proceed autothermally.

  13. Reduction of lunar landing fuel requirements by utilizing lunar ballistic capture.

    PubMed

    Johnson, Michael D; Belbruno, Edward A

    2005-12-01

    Ballistic lunar capture trajectories have been successfully utilized for lunar orbital missions since 1991. Recent interest in lunar landing trajectories has occurred due to a directive from President Bush to return humans to the Moon by 2015. NASA requirements for humans to return to the lunar surface include separation of crew and cargo missions, all lunar surface access, and anytime-abort to return to Earth. Such requirements are very demanding from a propellant standpoint. The subject of this paper is the application of lunar ballistic capture for the reduction of lunar landing propellant requirements. Preliminary studies of the application of weak stability boundary (WSB) trajectories and ballistic capture have shown that considerable savings in low Earth orbit (LEO) mission mass may be realized, on the order of 36% less than conventional Hohmann transfer orbit missions. Other advantages, such as reduction in launch window constraints and reduction of lunar orbit maintenance propellant requirements, have also surfaced from this study. PMID:16510407

  14. Evaluation of fuel additives for reduction of material imcompatibilities in methanol-gasoline blends

    NASA Technical Reports Server (NTRS)

    Rodriguez, C. F.; Barbee, J. G.; Knutson, W. K.; Cuellar, J. P., Jr.

    1983-01-01

    Screening tests determined the efficacy of six commercially available additives as modifiers of methanol's corrosivity toward metals and its weakening of tensile properties of nonmetals in automotive fuel systems. From the screening phase, three additives which seemed to protect some of the metals were tested in higher concentrations and binary combinations in search of optimal application conditions. Results indicate that two of the additives have protective properties and combining them increases the protection of the metals corroded by methanol-gasoline blends. Half of the metals in the tests were not corroded. Testing at recommended concentrations and then at higher concentrations and in combinations shows that the additives would have no protective or harmful effects on the nonmetals. Two additives emerged as candidates for application to the protection of metals in automotive methanol-gasoline fuel systems. The additives tested were assigned letter codes to protect their proprietary nature.

  15. Liquid Fuel From Microbial Communities: Electroalcoholgenesis: Bioelectrochemical Reduction of CO2 to Butanol

    SciTech Connect

    2010-07-01

    Electrofuels Project: MUSC is developing an engineered system to create liquid fuels from communities of interdependent microorganisms. MUSC is first pumping carbon dioxide (CO2) and renewable sources of electricity into a battery-like cell. A community of microorganisms uses the electricity to convert the CO2 into hydrogen. That hydrogen is then consumed by another community of microorganisms living in the same system. These new microorganisms convert the hydrogen into acetate, which in turn feed yet another community of microorganisms. This last community of microorganisms uses the acetate to produce a liquid biofuel called butanol. Similar interdependent microbial communities can be found in some natural environments, but they’ve never been coupled together in an engineered cell to produce liquid fuels. MUSC is working to triple the amount of butanol that can be produced in its system and to reduce the overall cost of the process.

  16. Reduction of gaseous pollutant emissions from gas turbine combustors using hydrogen-enriched jet fuel

    NASA Technical Reports Server (NTRS)

    Clayton, R. M.

    1976-01-01

    Recent progress in an evaluation of the applicability of the hydrogen enrichment concept to achieve ultralow gaseous pollutant emission from gas turbine combustion systems is described. The target emission indexes for the program are 1.0 for oxides of nitrogen and carbon monoxide, and 0.5 for unburned hydrocarbons. The basic concept utilizes premixed molecular hydrogen, conventional jet fuel, and air to depress the lean flammability limit of the mixed fuel. This is shown to permit very lean combustion with its low NOx production while simulataneously providing an increased flame stability margin with which to maintain low CO and HC emission. Experimental emission characteristics and selected analytical results are presented for a cylindrical research combustor designed for operation with inlet-air state conditions typical for a 30:1 compression ratio, high bypass ratio, turbofan commercial engine.

  17. Diesel Emission Reduction By On-Board Fuel Reformulation. Final Report

    SciTech Connect

    D. L. Jassby; A. Rabinovich; L. Bromberg; N. Domingo

    2000-03-01

    In this Phase 1 proposal, four tasks were investigated: plasma reforming in the mode of energy neutral reforming, testing in a diesel engine with hydrogen injection (port-injection), analysis of the data, and system analysis. It was demonstrated that it is feasible using a compact microplasmatron fuel converter to obtain near energy neutral reforming. Hydrogen addition was used in a compression ignition engine and a factor of 10 decrease in the particulate size concentration and mass was achieved.

  18. Fuel Efficient Strategies for Reducing Contrail Formations in United States Air Space

    NASA Technical Reports Server (NTRS)

    Sridhar, Banavar; Chen, Neil Y.; Ng, Hok K.

    2010-01-01

    This paper describes a class of strategies for reducing persistent contrail formation in the United States airspace. The primary objective is to minimize potential contrail formation regions by altering the aircraft's cruising altitude in a fuel-efficient way. The results show that the contrail formations can be reduced significantly without extra fuel consumption and without adversely affecting congestion in the airspace. The contrail formations can be further reduced by using extra fuel. For the day tested, the maximal reduction strategy has a 53% contrail reduction rate. The most fuel-efficient strategy has an 8% reduction rate with 2.86% less fuel-burnt compared to the maximal reduction strategy. Using a cost function which penalizes extra fuel consumed while maximizing the amount of contrail reduction provides a flexible way to trade off between contrail reduction and fuel consumption. It can achieve a 35% contrail reduction rate with only 0.23% extra fuel consumption. The proposed fuel-efficient contrail reduction strategy provides a solution to reduce aviation-induced environmental impact on a daily basis.

  19. Observation of Porosity Reduction in a Densification-Prone Test Fuel Rod: Data and Analysis

    SciTech Connect

    Cunningham, M. E.; Daniel, J. L.; Lanning, D. D.

    1981-10-01

    Instrumented fuel assembly (IFA)-431 was irradiated in the Halden Boiling Water Reactor (HBWR) for the purpose of extending the steady-state data base. Rod 6 of this assembly began irradiation with UO{sub 2} fuel of 92% theoretical density (TD) that was unstable with respect to in-reactor densification. Thermal resintering tests resulted in a final density of 95.3% TD while post-irradiation examination (PIE) indicated a final density of 96.5% TD. Observed microstructural changes were consistent with published densification studies; there was a marked depletion of submicrometer diameter pores and total pore volume. However, grain size increased only slightly, indicating that internal pellet temperatures did not reach the 1875K applied in resintering tests. Oensification was observed to increase the temperatures in rod 6, but temperatures did not become as high as for a sibling rod that simulated instantaneous densification. Temperatures calculated with U.S. Nuclear Regulatory Commission (NRC) fuel performance computer codes were generally higher than observed temperatures.

  20. Demonstration of improved vehicle fuel efficiency through innovative tire design, materials, and weight reduction technologies

    SciTech Connect

    Donley, Tim

    2014-12-31

    Cooper completed an investigation into new tire technology using a novel approach to develop and demonstrate a new class of fuel efficient tires using innovative materials technology and tire design concepts. The objective of this work was to develop a new class of fuel efficient tires, focused on the “replacement market” that would improve overall passenger vehicle fuel efficiency by 3% while lowering the overall tire weight by 20%. A further goal of this project was to accomplish the objectives while maintaining the traction and wear performance of the control tire. This program was designed to build on what has already been accomplished in the tire industry for rolling resistance based on the knowledge and general principles developed over the past decades. Cooper’s CS4 (Figure #1) premium broadline tire was chosen as the control tire for this program. For Cooper to achieve the goals of this project, the development of multiple technologies was necessary. Six technologies were chosen that are not currently being used in the tire industry at any significant level, but that showed excellent prospects in preliminary research. This development was divided into two phases. Phase I investigated six different technologies as individual components. Phase II then took a holistic approach by combining all the technologies that showed positive results during phase one development.

  1. Implications from the Use of Non-timber Forest Products on the Consumption of Wood as a Fuel Source in Human-Dominated Semiarid Landscapes.

    PubMed

    Cavalcanti, Maria Clara B T; Ramos, Marcelo Alves; Araújo, Elcida L; Albuquerque, Ulysses P

    2015-08-01

    Little is known about what possible effects on wood resources might be caused by non-timber forest products (NTFPs). Here, we assessed the patterns of fuelwood consumption related to an NTFP (Caryocar coriaceum) oil extraction and how this non-domestic activity can indirectly increase the use pressure on fuelwood species in a protected area, semiarid of Brazil. We conducted semi-structured interviews, in situ inventories, phytosociological surveys, and analyses of wood quality to identify the set of woody plants used in oil production. Householders use large volumes of dry wood and a set of woody species, which are highly exploited. Additionally, many preferred species have low fuel potential and suffer much use pressure. The best fuelwood species are underused, what requires management strategies to improve their potential as a source of energy. As a result, we suggest some conservation and management actions of fuelwood resources related to the use of NTFPs. PMID:25907282

  2. Implications from the Use of Non-timber Forest Products on the Consumption of Wood as a Fuel Source in Human-Dominated Semiarid Landscapes

    NASA Astrophysics Data System (ADS)

    Cavalcanti, Maria Clara B. T.; Ramos, Marcelo Alves; Araújo, Elcida L.; Albuquerque, Ulysses P.

    2015-08-01

    Little is known about what possible effects on wood resources might be caused by non-timber forest products (NTFPs). Here, we assessed the patterns of fuelwood consumption related to an NTFP ( Caryocar coriaceum) oil extraction and how this non-domestic activity can indirectly increase the use pressure on fuelwood species in a protected area, semiarid of Brazil. We conducted semi-structured interviews, in situ inventories, phytosociological surveys, and analyses of wood quality to identify the set of woody plants used in oil production. Householders use large volumes of dry wood and a set of woody species, which are highly exploited. Additionally, many preferred species have low fuel potential and suffer much use pressure. The best fuelwood species are underused, what requires management strategies to improve their potential as a source of energy. As a result, we suggest some conservation and management actions of fuelwood resources related to the use of NTFPs.

  3. REDUCTION OF CO2 EMISSIONS FROM MOBILE SOURCES BY ALTERNATIVE FUELS DERIVED FROM BIOMASS

    EPA Science Inventory

    The paper discusses process options for utilizing biomass to obtain greatest reduction of carbon dioxide (CO2) emissions from motor vehicles at least cost. (NOTE: The Energy Policy Act of 1992 seeks to displace 30% of the U.S. petroleum requirement by the year 2010 with an altern...

  4. Sectoral CO 2, CH 4, N 2O and SO 2 emissions from fossil fuel consumption in Nagpur City of Central India

    NASA Astrophysics Data System (ADS)

    Majumdar, Deepanjan; Gajghate, D. G.

    2011-08-01

    Emission inventory of CO 2, CH 4, N 2O and SO 2 has been prepared for Nagpur city in Central India for the year 2004. Data on fossil fuel (coal, light diesel oil, high speed diesel, petrol/gasoline, low sulphur heavy stock, furnace oil and kerosene) consumption in thermal power, industrial, transport and domestic sectors were collected. Thermal power sector had the maximum coal consumption followed by the industrial and domestic sectors, whereas kerosene, liquefied petroleum gas (LPG), diesel and gasoline were used only in any single sector. Total annual CO 2, CH 4, N 2O and SO 2 emissions from these fuels in Nagpur city for the year 2004 was found to be 14792418 MT (14.8 Tg), 4649 (4.6 Tg), 1529 (1.5 Tg) and 69093 (6.9 Tg), respectively, in which thermal power and domestic sector had the maximum share. Coal was found to be the major contributor to Green House Gas (GHG) and SO 2 emissions in all the sectors barring transport and domestic sectors. Carbon dioxide was the predominant GHG emitted by the selected sectors in terms of absolute emissions and also global warming contribution (GWC), though the share in the latter was lesser in magnitude due to higher global warming potential (GWP) of CH 4 and N 2O than CO 2. Thermal power sector had a share of 51% in total CO 2 emissions from all the sectors, followed by domestic, industrial and transport sectors having 27, 12 and 10% contributions, respectively. Share of thermal power sector in total SO 2 emissions was 61%, followed by 24% from industrial, 10% from domestic and 5% from transport sector.

  5. Graphene/biofilm composites for enhancement of hexavalent chromium reduction and electricity production in a biocathode microbial fuel cell.

    PubMed

    Song, Tian-Shun; Jin, Yuejuan; Bao, Jingjing; Kang, Dongzhou; Xie, Jingjing

    2016-11-01

    In this study, a simple method of biocathode fabrication in a Cr(VI)-reducing microbial fuel cell (MFC) is demonstrated. A self-assembling graphene was decorated onto the biocathode microbially, constructing a graphene/biofilm, in situ. The maximum power density of the MFC with a graphene biocathode is 5.7 times that of the MFC with a graphite felt biocathode. Cr(VI) reduction was also enhanced, resulting in 100% removal of Cr(VI) within 48h, at 40mg/L Cr(VI), compared with only 58.3% removal of Cr(VI) in the MFC with a graphite felt biocathode. Cyclic voltammogram analyses showed that the graphene biocathode had faster electron transfer kinetics than the graphite felt version. Energy dispersive spectrometer (EDS) and X-ray photoelectron spectra (XPS) analysis revealed a possible adsorption-reduction mechanism for Cr(VI) reduction via the graphene biocathode. This study attempts to improve the efficiency of the biocathode in the Cr(VI)-reducing MFC, and provides a useful candidate method for the treatment of Cr(VI) contaminated wastewater, under neutral conditions. PMID:27262274

  6. Electrocatalytic Activity of Transition Metal Oxide-Carbon Composites for Oxygen Reduction in Alkaline Batteries and Fuel Cells

    SciTech Connect

    Malkhandi, S; Trinh, P; Manohar, AK; Jayachandrababu, KC; Kindler, A; Prakash, GKS; Narayanan, SR

    2013-06-07

    Conductive transition metal oxides (perovskites, spinels and pyrochlores) are attractive as catalysts for the air electrode in alkaline rechargeable metal-air batteries and fuel cells. We have found that conductive carbon materials when added to transition metal oxides such as calcium-doped lanthanum cobalt oxide, nickel cobalt oxide and calcium-doped lanthanum manganese cobalt oxide increase the electrocatalytic activity of the oxide for oxygen reduction by a factor of five to ten. We have studied rotating ring-disk electrodes coated with (a) various mass ratios of carbon and transition metal oxide, (b) different types of carbon additives and (c) different types of transition metal oxides. Our experiments and analysis establish that in such composite catalysts, carbon is the primary electro- catalyst for the two-electron electro-reduction of oxygen to hydroperoxide while the transition metal oxide decomposes the hydroperoxide to generate additional oxygen that enhances the observed current resulting in an apparent four-electron process. These findings are significant in that they change the way we interpret previous reports in the scientific literature on the electrocatalytic activity of various transition metal oxide- carbon composites for oxygen reduction, especially where carbon is assumed to be an additive that just enhances the electronic conductivity of the oxide catalyst. (C) 2013 The Electrochemical Society. All rights reserved.

  7. Fuel Damage Reduction by Installation of Particle Traps in the Feedwater Lines

    SciTech Connect

    Henriksson, Mats; Westin, Johan; Lindqvist, Hans; Lundstrom, Anders; Alavyoon, Farid; Kaipainen, Tapio

    2006-07-01

    Fuel damages are commonly caused by grinding of the cladding due to debris entering the reactor pressure vessel. In order to reduce the probability for fuel damages so-called particle traps have been developed and are currently in operation in two Swedish nuclear power plants. The particle traps are of type axial centrifugal separators, and are characterized by a robust design, high separation rate and low pressure drop (typically less than 1 bar). Special care has been taken in the design of the flow straightener, which efficiently eliminates the swirl in the flow. The model tests show that the Swirl number downstream of the particle trap is typically the same order of magnitude or less than that downstream of a pipe bend. The particles are separated from the main flow and collected in a separate chamber, which is emptied only during the outages. Traps have been developed for both upward or downward flow direction, with feedwater flows from 300 to 900 kg/s. The present paper describes the development work, which is primarily based on full-scale model tests supported by CFD-calculations. Some operating experiences from plants in which particle traps currently are in use are also reported. (authors)

  8. Soil factors of ecosystems' disturbance risk reduction under the impact of rocket fuel

    NASA Astrophysics Data System (ADS)

    Krechetov, Pavel; Koroleva, Tatyana; Sharapova, Anna; Chernitsova, Olga

    2016-04-01

    Environmental impacts occur at all stages of space rocket launch. One of the most dangerous consequences of a missile launch is pollution by components of rocket fuels ((unsymmetrical dimethylhydrazine (UDMH)). The areas subjected to falls of the used stages of carrier rockets launched from the Baikonur cosmodrome occupy thousands of square kilometers of different natural landscapes: from dry steppes of Kazakhstan to the taiga of West Siberia and mountains of the Altai-Sayany region. The study aims at assessing the environmental risk of adverse effects of rocket fuel on the soil. Experimental studies have been performed on soil and rock samples with specified parameters of the material composition. The effect of organic matter, acid-base properties, particle size distribution, and mineralogy on the decrease in the concentration of UDMH in equilibrium solutions has been studied. It has been found that the soil factors are arranged in the following series according to the effect on UDMH mobility: acid-base properties > organic matter content >clay fraction mineralogy > particle size distribution. The estimation of the rate of self-purification of contaminated soil is carried out. Experimental study of the behavior of UDMH in soil allowed to define a model for calculating critical loads of UDMH in terrestrial ecosystems.

  9. The enhancement of ammonium removal from ethanolamine wastewater using air-cathode microbial fuel cells coupled to ferric reduction.

    PubMed

    Shin, Ja-Won; Seo, Seok-Ju; Maitlo, Hubdar Ali; Park, Joo-Yang

    2015-08-01

    A microbial fuel cell (MFC) with biological Fe(III) reduction was implemented for simultaneous ethanolamine (ETA) degradation and electrical energy generation. In the feasibility experiment using acetate as a substrate in a single-chamber MFC with goethite and ammonium at a ratio of 3.0(mol/mol), up to 96.1% of the ammonium was removed through the novel process related to Fe(III). In addition, the highest voltage output (0.53V) and maximum power density (0.49Wm(-2)) were obtained. However, the ammonium removal and electrical performance decreased as acetate was replaced with ETA. In the long-term experiment, the electrical performance markedly decreased where the voltage loss increased due to Fe deposition on the membranes. PMID:25804534

  10. The Stability Challenge on the Pathway to Low and Ultra‐Low Platinum Loading for Oxygen Reduction in Fuel Cells

    PubMed Central

    Cherevko, Serhiy

    2015-01-01

    Abstract We report the influence of catalyst loading on rates of platinum degradation in acidic electrolyte at room temperature. A piezoelectric printer is used to deposit spotted arrays of a commercially available catalyst comprised of Pt nanoparticles on a porous carbon support. The kinetically controlled oxygen reduction reaction (ORR) activity at different loadings is measured using an electrochemical scanning flow cell (SFC), and found to be quite stable over the range of loadings studied. This behaviour, however, contrasts sharply with rates of both transient and quasi‐steady‐state platinum dissolution. These are shown using downstream inductively coupled plasma mass spectrometry (ICP‐MS) analytics, to increase as loading becomes lower. This dichotomy between activity and stability has direct implications for the development of improved catalyst materials, as well as for the achievement of current targets for reduced loadings of noble metals for fuel cells and other energy storage devices. PMID:27525211

  11. Effects of surface chemistry and microstructure of electrolyte on oxygen reduction kinetics of solid oxide fuel cells

    NASA Astrophysics Data System (ADS)

    Park, Joong Sun; An, Jihwan; Lee, Min Hwan; Prinz, Fritz B.; Lee, Wonyoung

    2015-11-01

    We report systematic investigation of the surface properties of yttria-stabilized zirconia (YSZ) electrolytes with the control of the grain boundary (GB) density at the surface, and its effects on electrochemical activities. The GB density of thin surface layers deposited on single crystal YSZ substrates is controlled by changing the annealing temperature (750-1450 °C). Higher oxygen reduction reactions (ORR) kinetics is observed in samples annealed at lower temperatures. The higher ORR activity is ascribed to the higher GB density at the YSZ surface where 'mobile' oxide ion vacancies are more populated. Meanwhile, oxide ion vacancies concurrently created with yttrium segregation at the surface at the higher annealing temperature are considered inactive to oxygen incorporation reactions. Our results provide additional insight into the interplay between the surface chemistry, microstructures, and electrochemical activity. They potentially provide important guidelines for engineering the electrolyte-electrode interfaces of solid oxide fuel cells for higher electrochemical performance.

  12. Effects of surface chemistry and microstructure of electrolyte on oxygen reduction kinetics of solid oxide fuel cells

    SciTech Connect

    Park, Joong Sun; An, Jihwan; Lee, Min Hwan; Prinz, Friedrich B.; Lee, Wonyoung

    2015-07-10

    In this study, we report systematic investigation of the surface properties of yttria-stabilized zirconia (YSZ) electrolytes with the control of the grain boundary (GB) density at the surface, and its effects on electrochemical activities. The GB density of thin surface layers deposited on single crystal YSZ substrates is controlled by changing the annealing temperature (750-1450 °C). Higher oxygen reduction reactions (ORR) kinetics is observed in samples annealed at lower temperatures. The higher ORR activity is ascribed to the higher GB density at the YSZ surface where 'mobile' oxide ion vacancies are more populated. Meanwhile, oxide ion vacancies concurrently created with yttrium segregation at the surface at the higher annealing temperature are considered inactive to oxygen incorporation reactions. Our results provide additional insight into the interplay between the surface chemistry, microstructures, and electrochemical activity. They potentially provide important guidelines for engineering the electrolyte electrode interfaces of solid oxide fuel cells for higher electrochemical performance.

  13. Open framework metal chalcogenides as efficient photocatalysts for reduction of CO2 into renewable hydrocarbon fuel.

    PubMed

    Sasan, Koroush; Lin, Qipu; Mao, Chengyu; Feng, Pingyun

    2016-06-01

    Open framework metal chalcogenides are a family of porous semiconducting materials with diverse chemical compositions. Here we show that these materials containing covalent three-dimensional superlattices of nanosized supertetrahedral clusters can function as efficient photocatalysts for the reduction of CO2 to CH4. Unlike dense semiconductors, metal cations are successfully incorporated into the channels of the porous semiconducting materials to further tune the physical properties of the materials such as electrical conductivity and band gaps. In terms of the photocatalytic properties, the metal-incorporated porous chalcogenides demonstrated enhanced solar energy absorption and higher electrical conductivity and improved photocatalytic activity. PMID:27186825

  14. Soda-fuel metallurgy: Metal ions for carbon neutral CO2 and H2O reduction

    NASA Astrophysics Data System (ADS)

    Neelameggham, Neale R.

    2009-04-01

    The role of minerals in biomass formation is understood only to a limited extent. When the term “photosynthesis—CO2 and H2O reduction of sugars, using solar energy”—is used, one normally thinks of chlorophyll as a compound containing magnesium. Alkali and alkaline earth metals present in leaf cells in the form of ions are equally essential in this solar energy bioconversion coupled with nitrogen fixation. Application of some of these principles can lead to artificial carbon-neutral processes on an industrial scale close to the concentrated CO2 emission sources.

  15. A study of NO{sub x} reduction by fuel injection recirculation. Final report, January 1995--June 1996

    SciTech Connect

    Feese, J.J.; Turns, S.R.

    1996-08-01

    Flue-gas recirculation (FGR) is a well-known method used to control oxides of nitrogen (NO{sub x}) in industrial burner applications. Recent small- and large-scale experiments in natural-gas fired boilers have shown that introducing the recirculated flue gases with the fuel results in a much greater reduction in NO{sub x}, per unit mass of gas recirculated, in comparison to introducing the flue gases with the combustion air. That fuel injection recirculation (FIR) is more effective than windbox FGR is quite remarkable. At present, however, there is no definitive understanding of why FIR is more effective than conventional FGR. The objective of the present investigation is to ascertain whether or not chemical and/or molecular transport effects alone can explain the differences in NO{sub x} reduction observed between FIR and FGR by studying laminar diffusion flames. The purpose of studying laminar flames is to isolate chemical effects from the effects of turbulent mixing and heat transfer, which are inherent in practical boilers. The results of both the numerical simulations and the experiments suggest that, although molecular transport and chemical kinetic phenomena are affected by the location of diluent addition depending on flow conditions, the greater effectiveness of FIR over FGR in practical applications may result from differences in turbulent mixing and heat transfer. Further research is required to understand how differences in diluent-addition location affect NO{sub x} production in turbulent flames. The present study, however, provides an underlying basis for understanding how flow conditions can affect flame chemistry. 51 figs., 7 tabs.

  16. Electrocatalytic reduction of dioxygen on PdCu for polymer electrolyte membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Martínez-Casillas, D. C.; Vázquez-Huerta, G.; Pérez-Robles, J. F.; Solorza-Feria, O.

    2011-05-01

    The present research is aimed to study the oxygen reduction reaction (ORR) on a PdCu electrocatalyst synthesized through reduction of PdCl2 and CuCl with NaBH4 in a THF solution. Characterization of PdCu electrocatalyst was performed by X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy-dispersive X-ray (EDX) spectroscopy. Characterization results showed that the synthesis method produced spherical agglomerated nanocrystalline PdCu particles of about 10 nm size. The electrochemical activity was evaluated using cyclic voltammetry (CV), rotating disc electrode (RDE) and electrochemical impedance spectroscopy (EIS) in a 0.5 M H2SO4 electrolyte at 25 °C. The onset potential for ORR on PdCu is shifted by ca. 30 mV to more positive values and enhanced catalytic current densities were observed, compared to that of pure Pd catalyst. The synthesized PdCu electrocatalyst dispersed on a carbon black support was tested as cathode electrode in a membrane-electrode assembly (MEA) achieving a power density of 150 mW cm-2 at 0.38 V and 80 °C.

  17. Open framework metal chalcogenides as efficient photocatalysts for reduction of CO2 into renewable hydrocarbon fuel

    NASA Astrophysics Data System (ADS)

    Sasan, Koroush; Lin, Qipu; Mao, Chengyu; Feng, Pingyun

    2016-05-01

    Open framework metal chalcogenides are a family of porous semiconducting materials with diverse chemical compositions. Here we show that these materials containing covalent three-dimensional superlattices of nanosized supertetrahedral clusters can function as efficient photocatalysts for the reduction of CO2 to CH4. Unlike dense semiconductors, metal cations are successfully incorporated into the channels of the porous semiconducting materials to further tune the physical properties of the materials such as electrical conductivity and band gaps. In terms of the photocatalytic properties, the metal-incorporated porous chalcogenides demonstrated enhanced solar energy absorption and higher electrical conductivity and improved photocatalytic activity.Open framework metal chalcogenides are a family of porous semiconducting materials with diverse chemical compositions. Here we show that these materials containing covalent three-dimensional superlattices of nanosized supertetrahedral clusters can function as efficient photocatalysts for the reduction of CO2 to CH4. Unlike dense semiconductors, metal cations are successfully incorporated into the channels of the porous semiconducting materials to further tune the physical properties of the materials such as electrical conductivity and band gaps. In terms of the photocatalytic properties, the metal-incorporated porous chalcogenides demonstrated enhanced solar energy absorption and higher electrical conductivity and improved photocatalytic activity. Electronic supplementary information (ESI) available: The synthetic procedure, facilities information, EDX patterns and UV-Vis data. See DOI: 10.1039/c6nr02525k

  18. China: Emissions pattern of the world leader in CO2 emissions from fossil fuel consumption and cement production

    NASA Astrophysics Data System (ADS)

    Gregg, Jay S.; Andres, Robert J.; Marland, Gregg

    2008-04-01

    Release of carbon dioxide (CO2) from fossil fuel combustion and cement manufacture is the primary anthropogenic driver of climate change. Our best estimate is that China became the largest national source of CO2 emissions during 2006. Previously, the United States (US) had occupied that position. However, the annual emission rate in the US has remained relatively stable between 2001-2006 while the emission rate in China has more than doubled, apparently eclipsing that of the US in late 2006. Here we present the seasonal and spatial pattern of CO2 emissions in China, as well as the sectoral breakdown of emissions. Though our best point estimate places China in the lead position in terms of CO2 emissions, we qualify this statement in a discussion of the uncertainty in the underlying data (3-5% for the US; 15-20% for China). Finally, we comment briefly on the implications of China's new position with respect to international agreements to mitigate climate change.

  19. Consideration of Preparation Technique of Membrane Electrode Assembly of Polymer Electrolyte Fuel Cell for Reduction of Platinum Amount

    NASA Astrophysics Data System (ADS)

    Hidaka, Hiroaki; Sakaguchi, Yujiro; Suenaga, Yutaka; Tashima, Daisuke; Otsubo, Masahisa

    The purpose of this research is to design a structure of membrane electrode assembly (MEA) for reduction of a platinum amount considering with a reaction surface area, a various polarizations and a max power density by changing structure of catalyst layer numbers of MEA. Firstly, an operation of the multi-layered MEA was evaluated. As the result, the reaction surface area increases and the activation polarization decreases as increasing the number of catalyst layers in anode and cathode. In addition, the max power density increases with increasing the reaction surface area and the max power density increases with decreasing the activation polarization. However, a tendency of increasing of the reaction surface area and decreasing of the activation polarization saturated and the max power density decreased in the five-layered MEA. It was thought that flooding occurred by excessive stacking of the catalyst layers on cathode. Therefore, the optimal structure of multi-layered MEA was four-layered structure. In this study, it was clearly understood that multi-layered MEA was effective in increase of reaction surface area of the platinum catalyst, reduction of activation polarization and improvement of maximum output density. In addition, fuel cell module with multi-layered MEA was effective for reducing platinum amount.

  20. Self-sustained reduction of multiple metals in a microbial fuel cell-microbial electrolysis cell hybrid system.

    PubMed

    Li, Yan; Wu, Yining; Liu, Bingchuan; Luan, Hongwei; Vadas, Timothy; Guo, Wanqian; Ding, Jie; Li, Baikun

    2015-09-01

    A self-sustained hybrid bioelectrochemical system consisting of microbial fuel cell (MFC) and microbial electrolysis cell (MEC) was developed to reduce multiple metals simultaneously by utilizing different reaction potentials. Three heavy metals representing spontaneous reaction (chromium, Cr) and unspontaneous reaction (lead, Pb and nickel, Ni) were selected in this batch-mode study. The maximum power density of the MFC achieved 189.4 mW m(-2), and the energy recovery relative to the energy storage circuit (ESC) was ∼ 450%. At the initial concentration of 100 mg L(-1), the average reduction rate of Cr(VI) was 30.0 mg L(-1) d(-1), Pb(II) 32.7 mg L(-1) d(-1), and Ni(II) 8.9 mg L(-1) d(-1). An electrochemical model was developed to predict the change of metal concentration over time. The power output of the MFC was sufficient to meet the requirement of the ESC and MEC, and the "self-sustained metal reduction" was achieved in this hybrid system. PMID:26038328

  1. Nitrogen oxides reduction by carbonaceous materials and carbon dioxide separation using regenerative metal oxides from fossil fuel based flue gas

    NASA Astrophysics Data System (ADS)

    Gupta, Himanshu

    The ever-growing energy demands due to rising global population and continuing lifestyle improvements has placed indispensable emphasis on fossil fuels. Combustion of fossil fuels leads to the emission of harmful gaseous pollutants such as oxides of sulfur (SOx) and nitrogen (NOx), carbon dioxide (CO2), mercury, particulate matter, etc. Documented evidence has proved that this air pollution leads to adverse environmental health. This dissertation focuses on the development of technologies for the control of NOx and CO2 emissions. The first part of the thesis (Chapters 2--6) deals with the development of carbon based post combustion NOx reduction technology called CARBONOX process. High temperature combustion oxidizes both atmospheric nitrogen and organic nitrogen in coal to nitric oxide (NO). The reaction rate between graphite and NO is slow and requires high temperature (>900°C). The presence of metallic species in coal char catalyzes the reaction. The reaction temperature is lowered in the presence of oxygen to about 600--850°C. Chemical impregnation, specifically sodium compounds, further lowers the reaction temperature to 350--600°C. Activated high sodium lignite char (HSLC) provided the best performance for NO reduction. The requirement of char for NOx reduction is about 8--12 g carbon/g NO reduced in the presence of 2% oxygen in the inlet gas. The second part of this dissertation (chapter 7--8) focuses on the development of a reaction-based process for the separation of CO2 from combustion flue gas. Certain metal oxides react with CO2 forming metal carbonates under flue gas conditions. They can be calcined separately to yield CO2. Calcium oxide (CaO) has been identified as a viable metal oxide for the carbonation-calcination reaction (CCR) scheme. CaO synthesized from naturally occurring precursors (limestone and dolomite) attained 45--55% of their stoichiometric conversion due to the susceptibility of their microporous structure. High surface area

  2. Silver/iron oxide/graphitic carbon composites as bacteriostatic catalysts for enhancing oxygen reduction in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Ma, Ming; You, Shijie; Gong, Xiaobo; Dai, Ying; Zou, Jinlong; Fu, Honggang

    2015-06-01

    Biofilms from anode heterotrophic bacteria are inevitably formed over cathodic catalytic sites, limiting the performances of single-chamber microbial fuel cells (MFCs). Graphitic carbon (GC) - based nano silver/iron oxide (AgNPs/Fe3O4/GC) composites are prepared from waste pomelo skin and used as antibacterial oxygen reduction catalysts for MFCs. AgNPs and Fe3O4 are introduced in situ into the composites by one-step carbothermal reduction, enhancing their conductivity and catalytic activity. To investigate the effects of Fe species on the antibacterial and catalytic properties, AgNPs/Fe3O4/GC is washed with sulfuric acid (1 mol L-1) for 0.5 h, 1 h, and 5 h and marked as AgNPs/Fe3O4/GC-x (x = 0.5 h, 1 h and 5 h, respectively). A maximum power density of 1712 ± 35 mW m-2 is obtained by AgNPs/Fe3O4/GC-1 h, which declines by 4.12% after 17 cycles. Under catalysis of all AgNP-containing catalysts, oxygen reduction reaction (ORR) proceeds via the 4e- pathway, and no toxic effects to anode microorganisms result from inhibiting the cathodic biofilm overgrowth. With the exception of AgNPs/Fe3O4/GC-5 h, the AgNPs-containing composites exhibit remarkable power output and coulombic efficiency through lowering proton transfer resistance and air-cathode biofouling. This study provides a perspective for the practical application of MFCs using these efficient antibacterial ORR catalysts.

  3. Acetylene fuels reductive dechlorination of TCE by Dehalococcoides/Pelobacter-containing microbial consortia

    NASA Astrophysics Data System (ADS)

    Oremland, R. S.; Mao, X.; Mahandra, C.; Baesman, S. M.; Gushgari, S.; Alvarez-Cohen, L.; Liu, T.

    2015-12-01

    Groundwater contamination by trichloroethene (TCE) poses a threat to health and leads to the generation of vinyl chloride (VC), a carcinogen. Dehalococcoides mccartyi is the only bacterium that can completely dechlorinate TCE to ethene (C2H4). Acetylene (C2H2) occurs in TCE-contaminated sites as a consequence of chemical degradation of TCE. Yet acetylene inhibits a variety of microbial processes including methanogesis and reductive dechlorination. Pelobacter acetylenicus and related species can metabolize acetylene via acetylene hydratase and acetaldehyde dismutatse thereby generating acetate and H2 as endproducts, which could serve as electron donor and carbon source for growth of D. mccartyi. We found that 1mM acetylene (aqueous) inhibits growth of D. mccartyi strain 195 on 0.3 mM TCE, but that the inhibition was removed after 12 days with the addition of an acetylene-utilizing isolate from San Francisco Bay, Pelobacter strain SFB93. TCE did not inhibit the growth of this Pelobacter at the concentrations tested (0.1-0.5 mM) and TCE was not consumed by strain SFB93. Co-cultures of strain 195 with strain SFB93 at 5% inoculation were established in 120 mL serum bottles containing 40 mL defined medium. TCE was supplied at a liquid concentration of 0.1 mM, with 0.1 mM acetylene and N2/CO2 (90:10 v/v) headspace at 34 °C. Co-cultures were subsequently transferred (5% vol/vol inoculation) to generate subcultures after 20 μmol TCE was reduced to VC and 36 μmol acetylene was depleted. Aqueous H2 ranged from 114 to 217 nM during TCE-dechlorination, and the cell yield of strain 195 was 3.7 ±0.3 × 107 cells μmol-1 Cl- released. In a D. mccartyi-containing enrichment culture (ANAS) under the same conditions as above, it was found that inhibition of dechlorination by acetylene was reversed after 19 days by adding SFB93. Thus we showed that a co-culture of Pelobacter SFB93 and D. mccartyi 195 could be maintained with C2H2 as the electron donor and carbon source while TCE

  4. Oxygen reduction reaction on palladium-cobalt alloy catalysts for polymer electrolyte fuel cells

    NASA Astrophysics Data System (ADS)

    Oishi, Kentaro

    The Oxygen Reduction Reaction (ORR) activity in acid medium on Pd-Co was studied in this work. The catalysts were synthesized by two techniques; physical vapor deposition technique and ultrasonic spray reaction technique. The last technique was developed for the first time in our laboratory for the supported electro catalyst preparation and direct deposition onto the carbon paper or gas diffusion electrode the for PEMFC applications. The electrochemical properties such as the amount of hydrogen adsorption/desorption, the oxide formation/reduction of Pd-Co alloy catalyst have not been sufficiently studied before. Therefore these electrochemical properties were investigated by using the Pd-Co thin films prepared by sputtering method. A thin film catalyst cannot be directly used as an electrode of working PEMFCs, however the sputtering method is very useful since the chemical composition of alloy and surface area of the electrode can be controlled easily. Thus the fundamental electrochemical properties such as the amount of hydrogen adsorption/desorption, oxide formation/reduction and oxide reduction peak position on thin films of Pd-Co alloy, Pd and Pt catalysts were determined and their correlations to ORR catalytic activities in acid medium were studied. Enhancements of the catalytic activities for ORR by Pd-Co binary alloys were found to be in agreement with results obtained in previous studies. Ultrasonic spray reaction method was developed for the first time in our laboratory for carbon supported nano-scale catalyst for PEMFC application. Fine catalyst particles supported on high surface area carbon powder are required to apply the catalyst as the PEMFC cathode materials for the commercialization, but none of the studies done before were able to successfully obtain the Pd-Co fine particles which are comparable with the existing carbon supported platinum catalyst (ϕ2-4nm). Therefore the establishment of the catalyst synthesis method for Pd-Co fine particles are

  5. Effects of short-term, integrated body mass reduction program on maximal oxygen consumption and anaerobic alactic performance in obese subjects.

    PubMed

    Sartorio, A; Lafortuna, C L; Silvestri, G; Narici, M V

    2003-02-01

    The study investigated the effect of a short-term (3-week) body mass reduction program, combining energy-restricted diet, nutritional education, psychological counselling and aerobic exercise training (DEP-AT) on maximal oxygen consumption (VO2max) and anaerobic alactic performance evaluated with different techniques in obese patients (grade II and III). Fifty-three (14 males, 39 females) obese subjects [average +/- SD body mass index (BMI): 41.6 +/- 4.2 kg/m2] were tested before and after the DEP-AT program characterised by a daily conditioning protocol of aerobic exercise on cycloergometer, treadmill and armergometer for a total duration of 35 min at an intensity corresponding to 50% of individual VO2max during the first week of the program and at 60% in the following 2 weeks. VO2max was determined with the cycloergometric indirect method. Short-term alactic anaerobic performance was evaluated with: a) jumping test (5 consecutive jumps with maximal effort, Bosco technique), b) short sprint running test (8m), and c) stair climbing test (modified Margaria test). The DEP-AT program induced a significant weight loss (-4.57 +/- 1.26%, p < 0.001) and a significant VO2max increase (14.1 +/- 20.5%, p < 0.001). After the DEP-AT program, lower limb alactic anaerobic power output, calculated on a per kg body mass basis, increased significantly both in jumping and in stair climbing (20.1 +/- 24.8%, p < 0.001 and 13.5 +/- 19.75%, p < 0.001, respectively), as well as average horizontal velocity during short sprinting (7.2 +/- 17.6%, p < 0.01). Power output was a major determinant of the motor performance, being significantly correlated with: a) vertical displacement of the centre of gravity (R2 = 0.884, p < 0.001) in jumping test, b) vertical velocity (R2 = 0.348, p < 0.001) in stair climbing test, and c) horizontal velocity (R2 = 0.394, p < 0.001) in short running test. In conclusion, short-term DEP-AT program induces significant improvements in both aerobic capabilities and

  6. CO{sub 2}-mitigation measures through reduction of fossil fuel burning in power utilities. Which road to go?

    SciTech Connect

    Kaupp, A.

    1996-12-31

    Five conditions, at minimum, should be examined in the comparative analysis of CO{sub 2}-mitigation options for the power sector. Under the continuing constraint of scarce financial resources for any private or public investment in the power sector, the following combination of requirements characterise a successful CO{sub 2}-mitigation project: (1) Financial attractiveness for private or public investors. (2) Low, or even negative, long range marginal costs per ton of `CO{sub 2} saved`. (3) High impact on CO{sub 2}-mitigation, which indicates a large market potential for the measure. (4) The number of individual investments required to achieve the impact is relatively small. In other words, logistical difficulties in project implementation are minimised. (5) The projects are `socially fair` and have minimal negative impact on any segment of the society. This paper deals with options to reduce carbonaceous fuel burning in the power sector. Part I explains how projects should be selected and classified. Part II describes the technical options. Since reduction of carbonaceous fuel burning may be achieved through Demand Side Management (DSM) and Supply Side Management (SSM) both are treated. Within the context of this paper SSM does not mean to expand power supply as demand grows. It means to economically generate and distribute power as efficiently as possible. In too many instances DSM has degenerated into efficient lighting programs and utility managed incentives and rebate programs. To what extent this is a desirable situation for utilities in Developing Countries that face totally different problems as their counterparts in highly industrialised countries remains to be seen. Which road to go is the topic of this paper.

  7. Promotion of Oxygen Reduction by Exsolved Silver Nanoparticles on a Perovskite Scaffold for Low-Temperature Solid Oxide Fuel Cells.

    PubMed

    Zhu, Yinlong; Zhou, Wei; Ran, Ran; Chen, Yubo; Shao, Zongping; Liu, Meilin

    2016-01-13

    Solid oxide fuel cells (SOFCs) have potential to be the cleanest and most efficient electrochemical energy conversion devices with excellent fuel flexibility. To make SOFC systems more durable and economically competitive, however, the operation temperature must be significantly reduced, which depends sensitively on the development of highly active electrocatalysts for oxygen reduction reaction (ORR) at low temperatures. Here we report a novel silver nanoparticle-decorated perovskite oxide, prepared via a facile exsolution process from a Sr0.95Ag0.05Nb0.1Co0.9O3-δ (SANC) perovskite precursor, as a highly active and robust ORR electrocatalyst for low-temperature SOFCs. The exsolved Sr0.95Ag0.05Nb0.1Co0.9O3-δ (denoted as e-SANC) electrode is very active for ORR, achieving a very low area specific resistance (∼0.214 Ω cm(2) at 500 °C). An anode-supported cell with the new heterostructured cathode demonstrates very high peak power density (1116 mW cm(-2) at 500 °C) and stable operation for 140 h at a current density of 625 mA cm(-2). The superior ORR activity and stability are attributed to the fast oxygen surface exchange kinetics and the firm adhesion of the Ag nanoparticles to the Sr0.95Nb0.1Co0.9O3-δ (SNC0.95) support. Moreover, the e-SANC cathode displays improved tolerance to CO2. These unique features make the new heterostructured material a highly promising cathode for low-temperature SOFCs. PMID:26619096

  8. Preliminary Evaluation of a Turbine/Rotary Combustion Compound Engine for a Subsonic Transport. [fuel consumption and engine tests of turbofan engines

    NASA Technical Reports Server (NTRS)

    Civinskas, K. C.; Kraft, G. A.

    1976-01-01

    The fuel consumption of a modern compound engine with that of an advanced high pressure ratio turbofan was compared. The compound engine was derived from a turbofan engine by replacing the combustor with a rotary combustion (RC) engine. A number of boost pressure ratios and compression ratios were examined. Cooling of the RC engine was accomplished by heat exchanging to the fan duct. Performance was estimated with an Otto-cycle for two levels of energy lost to cooling. The effects of added complexity on cost and maintainability were not examined and the comparison was solely in terms of cruise performance and weight. Assuming a 25 percent Otto-cycle cooling loss (representative of current experience), the best compound engine gave a 1.2 percent improvement in cruise. Engine weight increased by 23 percent. For a 10 percent Otto-cycle cooling loss (representing advanced insulation/high temperature materials technology), a compound engine with a boost PR of 10 and a compression ratio of 10 gave an 8.1 percent lower cruise than the reference turbofan.

  9. Interpretation of high-resolution imagery for detecting vegetation cover composition change after fuels reduction treatments in woodlands

    USGS Publications Warehouse

    Karl, Jason W.; Gillan, Jeffrey K.; Barger, Nichole N.; Herrick, Jeffrey E.; Duniway, Michael C.

    2014-01-01

    discriminating fine vegetation and litter in imagery. Our results show that image interpretation to detect vegetation changes has utility for monitoring fuels reduction treatments in terms of woody vegetation and no-vegetation classes. The benefits of this technique are that it provides objective and repeatable measurements of site conditions that could be implemented relatively inexpensively and easily without the need for highly specialized software or technical expertise. Perhaps the biggest limitations of image interpretation to monitoring fuels treatments are challenges in estimating litter and herbaceous vegetation cover and the sensitivity of herbaceous cover estimates to image quality and shadowing.

  10. High pressure pyrolyzed non-precious metal oxygen reduction catalysts for alkaline polymer electrolyte membrane fuel cells.

    PubMed

    Sanetuntikul, Jakkid; Shanmugam, Sangaraju

    2015-05-01

    Non-precious metal catalysts, such as metal-coordinated to nitrogen doped-carbon, have shown reasonable oxygen reduction reaction (ORR) performances in alkaline fuel cells. In this report, we present the development of a highly active, stable and low-cost non-precious metal ORR catalyst by direct synthesis under autogenic-pressure conditions. Transmission electron microscopy studies show highly porous Fe-N-C and Co-N-C structures, which were further confirmed by Brunauer-Emmett-Teller surface area measurements. The surface areas of the Fe-N-C and Co-N-C catalysts were found to be 377.5 and 369.3 m(2) g(-1), respectively. XPS results show the possible existence of N-C and M-Nx structures, which are generally proposed to be the active sites in non-precious metal catalysts. The Fe-N-C electrocatalyst exhibits an ORR half-wave potential 20 mV higher than the reference Pt/C catalyst. The cycling durability test for Fe-N-C over 5000 cycles shows that the half-wave potential lost only 4 mV, whereas the half-wave potential of the Pt/C catalyst lost about 50 mV. The Fe-N-C catalyst exhibited an improved activity and stability compared to the reference Pt/C catalyst and it possesses a direct 4-electron transfer pathway for the ORR process. Further, the Fe-N-C catalyst produces extremely low HO2(-) content, as confirmed by the rotating ring-disk electrode measurements. In the alkaline fuel single cell tests, maximum power densities of 75 and 80 mW cm(-2) were observed for the Fe-N-C and Pt/C cathodes, respectively. Durability studies (100 h) showed that decay of the fuel cell current was more prominent for the Pt/C cathode catalyst compared to the Fe-N-C cathode catalyst. Therefore, the Fe-N-C catalyst appears to be a promising new class of non-precious metal catalysts prepared by an autogenic synthetic method. PMID:25833146

  11. Radiotoxicity and Risk Reduction of TRU Elements from Spent Fuel by Transmutation in the Light Water Reactor

    SciTech Connect

    Necas, Vladimir; Sebian, Vladimir; Kociskova, Karolina; Darilek, Petr

    2005-05-24

    A conventional PWR of type VVER-440 operating in a sustainable advanced fuel cycle mode with complete recycling of TRU elements in an Inert Matrix Combined Fuel Assembly (IMC-FA) in the same reactor was investigated. A preliminary assessment with the differences between various nuclear fuel cycles in terms of the risk analysis and its indicators has been conducted. The results indicate that the sustainable advanced fuel cycle option can, for the same amount of energy generation, significantly reduces both the amounts and radiotoxicity of the spent nuclear fuel in comparison with the conventional once-through UO2 or MOX fuel cycles.

  12. Strontium-doped samarium manganite as cathode materials for oxygen reduction reaction in solid oxide fuel cells

    NASA Astrophysics Data System (ADS)

    Li, W.; Xiong, C. Y.; Jia, L. C.; Pu, J.; Chi, B.; Chen, X.; Schwank, J. W.; Li, J.

    2015-06-01

    SmxSr1-xMnO3 with x = 0.3, 0.5 and 0.8, denoted as SSM37, SSM55 and SSM82, respectively, have been prepared via a sol-gel route as materials for cathodes in solid oxide fuel cells. Their activities in the oxygen reduction reaction (ORR) have been evaluated in comparison with the state-of-the-art cathode material La0.8Sr0.2MnO3 (LSM82) by electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS) and thermogravimetry (TG). Among all the prepared cathodes, the SSM55 exhibits the lowest values, while the LSM82 exhibits the highest polarization resistance, at open circuit voltage (OCV) and temperatures from 650 to 800 °C. This result indicates that the prepared SmxSr1-xMnO3 is a promising replacement for LSM82 as cathode material for SOFCs, and the SSM55 represents the optimal concentration in SmxSr1-xMnO3 series. The remarkably high ORR activity of the SSM55 is ascribed to its high surface Mn4+/Mn3+ and Oad/Olattice ratios and fast surface oxygen exchange kinetics.

  13. Barium carbonate nanoparticle to enhance oxygen reduction activity of strontium doped lanthanum ferrite for solid oxide fuel cell

    NASA Astrophysics Data System (ADS)

    Hong, Tao; Chen, Fanglin; Xia, Changrong

    2015-03-01

    BaCO3 nanoparticles are demonstrated as outstanding catalysts for high-temperature oxygen reduction reaction (ORR) on the La0.8Sr0.2FeO3-δ (LSF) cathode for solid oxide fuel cells (SOFCs) based on ytrria-stabilized zirconia (YSZ) electrolytes. Thermal gravitational and X-ray diffraction measurements show that BaCO3 is stable and chemically compatible with LSF under the fabrication and operation conditions of intermediate-temperature SOFCs. The BaCO3 nanoparticles can greatly reduce the interfacial polarization resistance; from 2.96 to 0.84 Ω cm2 at 700 °C when 12.9wt% BaCO3 is infiltrated to the porous LSF electrode on the YSZ electrolyte. Electrochemical impedance spectroscopy shows that there is about one order of magnitude decrease in the low-frequency resistance, indicating that BaCO3 nanoparticles can greatly enhance the surface steps for ORR. Electrical conductivity relaxation investigation indicates about one order of magnitude increase in the chemical oxygen surface exchange coefficient when BaCO3 is applied, directly demonstrating significant increase in the kinetics for ORR. In addition, LSF cathodes with infiltrated BaCO3 nanoparticles have shown excellent stability and substantially enhanced cell performance as demonstrated with single cells, suggesting BaCO3 nanoparticles are very effective in enhancing ORR on LSF.

  14. Carbon supported cobalt oxide nanoparticles-iron phthalocyanine as alternative cathode catalyst for oxygen reduction in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Ahmed, Jalal; Yuan, Yong; Zhou, Lihua; Kim, Sunghyun

    2012-06-01

    The high cost and limited resources of precious metals as oxygen reduction catalysts (ORR) hindered the widespread use of microbial fuel cells (MFCs) in practice. Here, the feasibility of metal oxide assisted metal macrocyclic complex was investigated as a catalyst for ORR in an air-cathode MFC. Electrochemical results revealed that cobalt oxide (CoOx) incorporation increased the ORR activity of iron phthalocyanine (FePc). In MFCs, the maximum power density of 654 ± 32 mW m-2 was achieved from the C-CoOx-FePc cathode, which was 37% higher than the power density of carbon supported FePc (C-FePc). The voltage output of the MFC only decreased to 85% of its initial voltage after 50 cycles, suggesting that the synthesized catalyst showed acceptable long-term stability. The voltage drop partially resulted from the covering of biofilm on the catalyst layer. This work provided a potential alternative to Pt in MFCs for sustainable energy generation.

  15. Effects of surface chemistry and microstructure of electrolyte on oxygen reduction kinetics of solid oxide fuel cells

    DOE PAGESBeta

    Park, Joong Sun; An, Jihwan; Lee, Min Hwan; Prinz, Friedrich B.; Lee, Wonyoung

    2015-07-10

    In this study, we report systematic investigation of the surface properties of yttria-stabilized zirconia (YSZ) electrolytes with the control of the grain boundary (GB) density at the surface, and its effects on electrochemical activities. The GB density of thin surface layers deposited on single crystal YSZ substrates is controlled by changing the annealing temperature (750-1450 °C). Higher oxygen reduction reactions (ORR) kinetics is observed in samples annealed at lower temperatures. The higher ORR activity is ascribed to the higher GB density at the YSZ surface where 'mobile' oxide ion vacancies are more populated. Meanwhile, oxide ion vacancies concurrently created withmore » yttrium segregation at the surface at the higher annealing temperature are considered inactive to oxygen incorporation reactions. Our results provide additional insight into the interplay between the surface chemistry, microstructures, and electrochemical activity. They potentially provide important guidelines for engineering the electrolyte electrode interfaces of solid oxide fuel cells for higher electrochemical performance.« less

  16. Bifunctional silver nanoparticle cathode in microbial fuel cells for microbial growth inhibition with comparable oxygen reduction reaction activity.

    PubMed

    An, Junyeong; Jeon, Hongrae; Lee, Jaeyoung; Chang, In Seop

    2011-06-15

    Organic contamination of water bodies in which benthic microbial fuel cells (benthic MFCs) are installed, and organic crossover from the anode to the cathode of membraneless MFCs, is a factor causing oxygen depletion and substrate loss in the cathode due to the growth of heterotrophic aerobic bacteria. This study examines the possible use of silver nanoparticles (AgNPs) as a cathodic catalyst for MFCs suffering from organic contamination and oxygen depletion. Four treated cathodes (AgNPs-coated, Pt/C-coated, Pt/C+AgNPs-coated, and plain graphite cathodes) were prepared and tested under high levels of organics loading. During operation (fed with 50 mM acetate), the AgNPs-coated system showed the highest DO concentration (0.8 mg/L) in the cathode area as well as the highest current (ranging from 0.04 to 0.12 mA). Based on these results, we concluded that (1) the growth of oxygen-consuming heterotrophic microbes could be inhibited by AgNPs, (2) the function of AgNPs as a bacterial growth inhibitor resulted in a greater increase of DO concentration in the cathode than the other tested cathode systems, (3) AgNPs could be applied as a cathode catalyst for oxygen reduction, and as a result (4) the MFC with the AgNPs-coated cathode led to the highest current generation among the tested MFCs. PMID:21585217

  17. Cellulose-derived nitrogen and phosphorus dual-doped carbon as high performance oxygen reduction catalyst in microbial fuel cell

    NASA Astrophysics Data System (ADS)

    Liu, Qin; Zhou, Yan; Chen, Shuiliang; Wang, Zejie; Hou, Haoqing; Zhao, Feng

    2015-01-01

    Microbial fuel cells (MFCs) couple functions of waste removal and electricity generation. The future success of MFCs inevitably depends on the increase of performance at decrease of material cost. Therefore, the use of renewable and sustainable materials, e.g. cellulose, to prepare high performance materials for MFCs would be an inevitable trend. In this communication, nitrogen and phosphorus dual-doped carbons were prepared by pyrolysis of cellulose using ammonium phosphate as doping source and employed as oxygen reduction reaction (ORR) catalyst in air-cathode of MFCs. A maximum power density of 2293 ± 50 mW m-2 was generated by the air-cathode using the dual-doped carbon catalyst, which was higher than the air-cathode using Pt/C catalyst with Pt load of 0.5 mg cm-2 (1680 ± 32 mW m-2). This study provided a facile and sustainable way to prepare low-cost and high-efficient ORR catalyst for scaled-up MFC applications.

  18. Microspheres assembled by KMn8O16 nanorods and their catalytic oxygen reduction activity in direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Fang, Yuan; Yang, Xiaodong; Wang, Li; Liu, Yongning

    2014-12-01

    Microspheres assembled using cryptomelane-type KMn8O16 nanorods are synthesized via a facile template-free, single-step hydrothermal technique. The synthesized KMn8O16 generates nanorods 10-20 nm in diameter and approximately 300-1000 nm long. The rods self-assemble to form microspheres of 2-6 μm in diameters. The electron transfer number for KMn8O16 during the ORR is approximately 3.98 at 0.5 V vs. Hg/HgO, and the H2O2 percentage is 0.66%. Moreover, a direct methanol fuel cell (DMFC) is built using KMn8O16 as cathodic catalyst, PtRu/C alloy as the anodic catalyst and a polymer fiber membrane (PFM) instead of a conventional polymer electrolyte membrane (PEM). The peak power densities (43.3 mW cm-2 and 153.9 mW cm-2) have been achieved at 25 °C and 70 °C, respectively. KMn8O16 shows good electrocatalytic activity and stability during oxygen reduction in alkaline solutions and demonstrates tolerance toward methanol poisoning.

  19. Energy and resource consumption

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The present and projected energy requirements for the United States are discussed. The energy consumption and demand sectors are divided into the categories: residential and commercial, transportation, and industrial and electrical generation (utilities). All sectors except electrical generation use varying amounts of fossile fuel resources for non-energy purposes. The highest percentage of non-energy use by sector is industrial with 71.3 percent. The household and commercial sector uses 28.4 percent, and transportation about 0.3 percent. Graphs are developed to project fossil fuel demands for non-energy purposes and the perdentage of the total fossil fuel used for non-energy needs.

  20. Application of fuel cells with heat recovery for integrated utility systems

    NASA Technical Reports Server (NTRS)

    Shields, V.; King, J. M., Jr.

    1975-01-01

    This paper presents the results of a study of fuel cell powerplants with heat recovery for use in an integrated utility system. Such a design provides for a low pollution, noise-free, highly efficient integrated utility. Use of the waste heat from the fuel cell powerplant in an integrated utility system for the village center complex of a new community results in a reduction in resource consumption of 42 percent compared to conventional methods. In addition, the system has the potential of operating on fuels produced from waste materials (pyrolysis and digester gases); this would provide further reduction in energy consumption.

  1. Are fuel poverty reduction schemes associated with decreased excess winter mortality in elders? A case study from London, U.K.

    PubMed

    El Ansari, Walid; El-Silimy, Sally

    2008-12-01

    The London Borough of Newham, London piloted the Warm Zone, a government-led fuel poverty reduction scheme. Fuel poverty is often cited as a factor in excess winter mortality (EWM) in the U.K. This study reported in this paper assessed whether EWM decreased for people aged > or =65 years in Newham as compared to all London, employing data from before and throughout the duration of the Warm Zone project. The paper also discusses the difficulties surrounding the measurement and interpretation of health impact relating to fuel poverty. We calculated and compared the yearly EWM indices for people aged > or =65 years for all of London, and for Newham over 12 years (1993-2005). The yearly EWM ratio for Newham in relation to all London was then calculated and compared. No definitive evidence to support the effect of the War Zone on EMW were noted. Relationships between EWM and fewer poverty reduction schemes are difficult to interpret, as many factors are entangled. These include cold strain and biological, genetic, gender, physiological, thermoregulation, environmental, meteorological, socio-economic, healthcare provision/expenditure, lifestyle and co-morbidity aspects, besides the challenges of sample sizes and whether other fuel poverty reduction schemes were simultaneously in operation. Those in privately owned housing might be ;masked' (underestimated) in their vulnerability to fuel poverty. Redefining the specific criteria for eligibility for fuel poverty grants and tackling heat inefficiency in privately owned homes not eligible for home heating improvement despite fulfilling other criteria for vulnerability requires attention. The implications are discussed. PMID:19091937

  2. Building Eco-Informatics: Examining the Dynamics of Eco-Feedback Design and Peer Networks to Achieve Sustainable Reductions in Energy Consumption

    ERIC Educational Resources Information Center

    Jain, Rishee K.

    2013-01-01

    The built environment accounts for a substantial portion of energy consumption in the United States and in many parts of the world. Due to concerns over rising energy costs and climate change, researchers and practitioners have started exploring the area of eco-informatics to link information from the human, natural and built environments.…

  3. [Fire behavior of Quercus mongolica leaf litter fuelbed under zero-slope and no-wind conditions. II. Analysis and modelling of fireline intensity, fuel consumption, and combustion efficiency].

    PubMed

    Zhang, Ji-Li; Liu, Bo-Fei; Di, Xue-Ying; Chu, Teng-Fei; Jin, Sen

    2013-12-01

    Mongolian oak (Quercus mongolica) is an important constructive and accompanying species in mixed broadleaf-conifer forest in Northeast China, In this paper, a laboratory burning experiment was conducted under zero-slope and no-wind conditions to study the effects of fuel moisture content, loading, and thickness on the fireline intensity, fuel consumption, and combustion efficiency of the Mongolian oak leaf litter fuelbed. The fuel moisture content, loading, and thickness all had significant effects on the three fire behavior indices, and there existed interactions between these three affecting factors. Among the known models, the Byram model could be suitable for the prediction of local leaf litter fire intensity only after re-parameterization. The re-estimated alpha and beta parameters of the re-parameterized Byram model were 98.009 and 1.099, with an adjusted determination coefficient of 0.745, the rooted mean square error (RMSE) of 8.676 kW x m(-1), and the mean relative error (MRE) of 21%, respectively (R2 = 0.745). The re-estimated a and b by the burning efficiency method proposed by Albini were 0.069 and 0.169, and the re-estimated values were all higher than 93%, being mostly overestimated. The Consume model had a stronger suitability for the fuel. The R2 of the general linear models established for fireline intensity, fuel consumption, and burning efficiency was 0.82, 0.73 and 0.53, and the RMSE was 8.266 kW x m(-1) 0.081 kg x m(-2), and 0.203, respectively. In low intensity surface fires, the fine fuels could not be completely consumed, and thus, to consider the leaf litter and fine fuel in some forest ecosystems being completely consumed would overestimate the carbon release from forest fires. PMID:24697055

  4. Reduction of Escherichia coli adherence to uroepithelial bladder cells after consumption of cranberry juice: a double-blind randomized placebo-controlled cross-over trial.

    PubMed

    Di Martino, P; Agniel, R; David, K; Templer, C; Gaillard, J L; Denys, P; Botto, H

    2006-02-01

    To determine the efficacy of the consumption of cranberry juice versus placebo with regard to the presence of in vitro bacterial anti-adherence activity in the urine of healthy volunteers. Twenty healthy volunteers, 10 men and 10 women, were included. The study was a double-blind, randomized, placebo-controlled, and cross-over study. In addition to normal diet, each volunteer received at dinner a single dose of 750 ml of a total drink composed of: (1) 250 ml of the placebo and 500 ml of mineral water, or (2) 750 ml of the placebo, or (3) 250 ml of the cranberry juice and 500 ml of mineral water, or (4) 750 ml of the cranberry juice. Each volunteer took the four regimens successively in a randomly order, with a washout period of at least 6 days between every change in regimen. The first urine of the morning following cranberry or placebo consumption was collected and used to support bacterial growth. Six uropathogenic Escherichia coli strains (all expressing type 1 pili; three positive for the gene marker for P-fimbriae papC and three negative for papC), previously isolated from patients with symptomatic urinary tract infections, were grown in urine samples and tested for their ability to adhere to the T24 bladder cell line in vitro. There were no significant differences in the pH or specific gravity between the urine samples collected after cranberry or placebo consumption. We observed a dose dependent significant decrease in bacterial adherence associated with cranberry consumption. Adherence inhibition was observed independently from the presence of genes encoding type P pili and antibiotic resistance phenotypes. Cranberry juice consumption provides significant anti-adherence activity against different E. coli uropathogenic strains in the urine compared with placebo. PMID:16397814

  5. Bifunctional Ag/Fe/N/C Catalysts for Enhancing Oxygen Reduction via Cathodic Biofilm Inhibition in Microbial Fuel Cells.

    PubMed

    Dai, Ying; Chan, Yingzi; Jiang, Baojiang; Wang, Lei; Zou, Jinlong; Pan, Kai; Fu, Honggang

    2016-03-23

    Limitation of the oxygen reduction reaction (ORR) in single-chamber microbial fuel cells (SC-MFCs) is considered an important hurdle in achieving their practical application. The cathodic catalysts faced with a liquid phase are easily primed with the electrolyte, which provides more surface area for bacterial overgrowth, resulting in the difficulty in transporting protons to active sites. Ag/Fe/N/C composites prepared from Ag and Fe-chelated melamine are used as antibacterial ORR catalysts for SC-MFCs. The structure-activity correlations for Ag/Fe/N/C are investigated by tuning the carbonization temperature (600-900 °C) to clarify how the active-constituents of Ag/Fe and N-species influence the antibacterial and ORR activities. A maximum power density of 1791 mW m(-2) is obtained by Ag/Fe/N/C (630 °C), which is far higher than that of Pt/C (1192 mW m(-2)), only having a decline of 16.14% after 90 days of running. The Fe-bonded N and the cooperation of pyridinic N and pyrrolic N in Ag/Fe/N/C contribute equally to the highly catalytic activity toward ORR. The ·OH or O2(-) species originating from the catalysis of O2 can suppress the biofilm growth on Ag/Fe/N/C cathodes. The synergistic effects between the Ag/Fe heterojunction and N-species substantially contribute to the high power output and Coulombic efficiency of Ag/Fe/N/C catalysts. These new antibacterial ORR catalysts show promise for application in MFCs. PMID:26938657

  6. Electronically conducting proton exchange polymers as catalyst supports for proton exchange membrane fuel cells. Electrocatalysis of oxygen reduction, hydrogen oxidation, and methanol oxidation

    SciTech Connect

    Lefebvre, M.C.; Qi, Z.; Pickup, P.G.

    1999-06-01

    A variety of supported catalysts were prepared by the chemical deposition of Pt and Pt-Ru particles on chemically prepared poly(3,4-ethylenedioxythiophene)/poly(styrene-4-sulfonate) (PEDOT/PSS) and PEDOT/polyvinylsulfate (PVS) composites. The polymer particles were designed to provide a porous, proton-conducting and electron-conducting catalyst support for use in fuel cells. These polymer-supported catalysts were characterized by electron microscopy, impedance spectroscopy, cyclic voltammetry, and conductivity measurements. Their catalytic activities toward hydrogen and methanol oxidation and oxygen reduction were evaluated in proton exchange membrane fuel-cell-type gas diffusion electrodes. Activities for oxygen reduction comparable to that obtained with a commercial carbon-supported catalyst were observed, whereas those for hydrogen and methanol oxidation were significantly inferior, although still high for prototype catalysts.

  7. Generation and reduction of nitrogen oxides in firing different kinds of fuel in a circulating fluidized bed

    NASA Astrophysics Data System (ADS)

    Munts, V. A.; Munts, Yu. G.; Baskakov, A. P.; Proshin, A. S.

    2013-11-01

    The processes through which nitrogen oxides are generated and reduced in the course of firing different kinds of fuel in a circulating fluidized bed are addressed. All experimental studies were carried by the authors on their own laboratory installations. To construct a model simulating the generation of nitrogen oxides, the fuel combustion process in a fluidized bed was subdivided into two stages: combustion of volatiles and combustion of coke residue. The processes through which nitrogen oxides are generated and reduced under the conditions of firing fuel with shortage of oxygen (which is one of efficient methods for reducing nitrogen oxide emissions in firing fuel in a fluidized bed) are considered.

  8. Response of white-footed mice (Peromyscus leucopus) to fire and fire surrogate fuel reduction treatments in a southern Appalachian hardwood forest

    USGS Publications Warehouse

    Greenberg, C.H.; Otis, D.L.; Waldrop, T.A.

    2006-01-01

    An experiment conducted as part of the multidisciplinary National Fire and Fire Surrogate Study was designed to determine effects of three fuel reduction techniques on small mammals and habitat structure in the southern Appalachian mountains. Four experimental units, each >14-ha were contained within each of three replicate blocks at the Green River Game Land, Polk County, NC. Treatments were (1) prescribed burning (B); (2) mechanical felling of shrubs and small trees (M); (3) mechanical felling + burning (MB); (4) controls (C). Mechanical understory felling treatments were conducted in winter 2001-2002, and prescribed burning was conducted in March 2003. After treatment, there were fewer live trees, more snags, and greater canopy openness in MB than in other treatments. Leaf litter depth was reduced by burning in both B and MB treatments, and tall shrub cover was reduced in all fuel reduction treatments compared to C. Coarse woody debris pieces and percent cover were similar among treatments and controls. We captured 990 individuals of eight rodent species a total of 2823 times. Because white-footed mice composed >79% of all captures, we focused on this species. Populations in experimental units increased 228% on average between 2001 and 2002, but there was no evidence of an effect of the mechanical treatment. From 2002 to 2003, all units again showed an average increase in relative population size, but increases were greater in MB than in the other treatments. Age structure and male to female ratio were not affected by the fuel reduction treatment. Average adult body weight declined from 2001 to 2002, but less so in M than in units that remained C in both years. The proportion of mice captured near coarse woody debris was similar to the proportion captured in open areas for all treatments, indicating that white-footed mice did not use coarse woody debris preferentially or change their use patterns in response to fuel reduction treatments. Land managers should

  9. Kinetics of oxygen reduction in perovskite cathodes for solid oxide fuel cells: A combined modeling and experimental approach

    NASA Astrophysics Data System (ADS)

    Miara, Lincoln James

    Solid oxide fuel cells (SOFCs) have the potential to replace conventional stationary power generation technologies; however, there are major obstacles to commercialization, the most problematic of which is poor cathode performance. Commercialization of SOFCs will follow when the mechanisms occurring at the cathode are more thoroughly understood and adapted for market use. The catalytic reduction of oxygen occurring in SOFC cathodes consists of many elementary steps such as gas phase diffusion, chemical and/or electrochemical reactions which lead to the adsorption and dissociation of molecular oxygen onto the cathode surface, mass transport of oxygen species along the surface and/or through the bulk of the cathode, and full reduction and incorporation of the oxygen at the cathode/electrolyte two or three phase boundary. Electrochemical impedance spectroscopy (EIS) is the main technique used to identify the occurrence of these different processes, but when this technique is used without an explicit model describing the kinetics it is difficult to unravel the interdependence of each of these processes. The purpose of this dissertation is to identify the heterogeneous reactions occurring at the cathode of an SOFC by combining experimental EIS results with mathematical models describing the time dependent behavior of the system. This analysis is performed on two different systems. In the first case, experimental EIS results from patterned half cells composed of Ca-doped lanthanum manganite (LCM)| yttria-doped ZrO2 (YSZ) are modeled to investigate the temperature and partial pressure of oxygen, pO2, dependence of oxygen adsorption/dissociation onto the LCM surface, surface diffusion of atomic oxygen, and electrochemical reduction and incorporation of the oxygen into the electrolyte in the vicinity of the triple phase boundary (TPB). This model determines the time-independent state-space equations from which the Faradaic admittance transfer function is obtained. The

  10. Pt nanoparticle-dispersed graphene-wrapped MWNT composites as oxygen reduction reaction electrocatalyst in proton exchange membrane fuel cell.

    PubMed

    Aravind, S S Jyothirmayee; Ramaprabhu, Sundara

    2012-08-01

    Chemical and electrical synergies between graphite oxide and multiwalled carbon nanotube (MWNT) for processing graphene wrapped-MWNT hybrids has been realized by chemical vapor deposition without any chemical functionalization. Potential of the hybrid composites have been demonstrated by employing them as electrocatalyst supports in proton exchange membrane fuel cells. The defects present in the polyelectrolyte, which have been wrapped over highly dispersed MWNT, act as anchoring sites for the homogeneous deposition of platinum nanoparticles. Single-cell proton exchange membrane fuel cells show that the power density of the hybrid composite-based fuel cells is higher compared to the pure catalyst-support-based fuel cells, because of enhanced electrochemical reactivity and good surface area of the nanocomposites. PMID:22850438

  11. 08FFL-0020Influence of High Fuel Rail Pressure and Urea Selective Catalytic Reduction on PM Formation in an Off-Highway Heavy-Duty Diesel Engine

    SciTech Connect

    Kass, Michael D; Domingo, Norberto; Storey, John Morse; Lewis Sr, Samuel Arthur

    2008-01-01

    The influence of fuel rail pressure (FRP) and urea-selective catalytic reduction (SCR) on particulate matter (PM) formation is investigated in this paper along with notes regarding the NOx and other emissions. Increasing FRP was shown to reduce the overall soot and total PM mass for four operating conditions. These conditions included two high speed conditions (2400 rpm at 540 and 270 Nm of torque) and two moderated speed conditions (1400 rpm at 488 and 325 Nm). The concentrations of CO2 and NOx increased with fuel rail pressure and this is attributed to improved fuel-air mixing. Interestingly, the level of unburned hydrocarbons remained constant (or increased slightly) with increased FRP. PM concentration was measured using an AVL smoke meter and scanning mobility particle sizer (SMPS); and total PM was collected using standard gravimetric techniques. These results showed that the smoke number and particulate concentrations decrease with increasing FRP. However the decrease becomes more gradual as very high rail pressures. Additionally, the total PM decreased with increasing FRP; however, the soluble organic fraction (SOF) reaches a maximum after which it declines with higher rail pressure. The total PM was collected for the two 1400 rpm conditions downstream of the engine, diesel oxidation catalyst, and a urea-SCR catalyst. The results show that significant PM reduction occurs in the SCR catalyst even during high rates of urea dosage. Analysis of the PM indicates that residual SOF is burned up in the SCR catalyst.

  12. A miniature fuel cell with monolithically fabricated Si electrodes - Reduction of residual porous Si on catalyst layer

    NASA Astrophysics Data System (ADS)

    Kobayashi, Masahiro; Suzuki, Takahiro; Hayase, Masanori

    2014-12-01

    Higher performance was obtained in our miniature fuel cells by reducing the residual porous Si on catalyst layers. We have developed a miniature polymer electrolyte fuel cell by forming monolithic Si electrodes with MEMS techniques, in which a catalyst layer was synthesized on a Si chip by modifying porous Si to porous Pt by a wet plating process. As a result of technical limitations in the fabrication process, porous Si was left on the porous Pt catalyst layer. The residual porous Si was intended to lower the fuel cell performance by blocking reactant gas supply, and the effect of the residual porous Si on fuel cell performance was studied. The anodization conditions for porous Si formation were varied, and several prototype fuel cells were prepared with residual porous Si of different thickness. It was confirmed that a thick residual porous Si layer reduced cell performance, and high power density comparable to conventional large scale fuel cells was obtained with the least residual porous Si.

  13. Alternative fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J. S.; Butze, H. F.; Friedman, R.; Antoine, A. C.; Reynolds, T. W.

    1977-01-01

    Potential problems related to the use of alternative aviation turbine fuels are discussed and both ongoing and required research into these fuels is described. This discussion is limited to aviation turbine fuels composed of liquid hydrocarbons. The advantages and disadvantages of the various solutions to the problems are summarized. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source. The second solution is to minimize energy consumption at the refinery and keep fuel costs down by relaxing specifications.

  14. Electrolytic reduction of a simulated oxide spent fuel and the fates of representative elements in a Li2O-LiCl molten salt

    NASA Astrophysics Data System (ADS)

    Park, Wooshin; Choi, Eun-Young; Kim, Sung-Wook; Jeon, Sang-Chae; Cho, Young-Hwan; Hur, Jin-Mok

    2016-08-01

    A series of electrolytic reduction experiments were carried out using a simulated oxide spent fuel to investigate the reduction behavior of elements in a mixed oxide condition and the fates of elements in the reduction process with 1.0 wt% Li2O-LiCl. It was found out that 155% of the theoretical charge was enough to reduce the simulated. Te and Eu were expected to possibly exist in the precipitate and on the anode surface, whereas Ba and Sr showed apparent dissolution behaviors. Rare earths showed relatively low metal fractions from 28.2 to 34.0% except for Y. And the solubility of rare earths was observed to be low due to the low concentration of Li2O. The reduction of U was successful as expected showing 99.8% of a metal fraction. Also it was shown that the reduction of ZrO2 would be effective when a relatively small amount was included in a metal oxide mixture.

  15. Extended Platinum Nanotubes as Fuel Cell Catalysts

    SciTech Connect

    Alia, S.; Pivovar, B. S.; Yan, Y.

    2012-01-01

    Energy consumption has relied principally on fossil fuels as an energy source; fuel cells, however, can provide a clean and sustainable alternative, an answer to the depletion and climate change concerns of fossil fuels. Within proton exchange membrane fuel cells, high catalyst cost and poor durability limit the commercial viability of the device. Recently, platinum nanotubes (PtNTs) were studied as durable, active catalysts, providing a platform to meet US Department of Energy vehicular activity targets.[1] Porous PtNTs were developed to increase nanotube surface area, improving mass activity for oxygen reduction without sacrificing durability.[2] Subsurface platinum was then replaced with palladium, forming platinum-coated palladium nanotubes.[3] By forming a core shell structure, platinum utilization was increased, reducing catalyst cost. Alternative substrates have also been examined, modifying platinum surface facets and increasing oxygen reduction specific activity. Through modification of the PtNT platform, catalyst limitations can be reduced, ensuring a commercially viable device.

  16. Oxygen Reduction Kinetics of La2-xSrxNiO 4+delta Electrodes for Solid Oxide Fuel Cells

    NASA Astrophysics Data System (ADS)

    Guan, Bo

    In the development of intermediate temperature solid oxide fuel cell (IT-SOFC), mixed ionic-electronic conductors (MIEC) have drawn big interests due to their both ionic and electronic species transport which can enlarge the 3-dimension of the cathode network. This thesis presents an investigation of MIEC of Ruddlesden-popper (RP) phases like K2NiF4 type La2NiO4+delta (LNO)-based oxides which have interesting transport, catalytic properties and suitable thermal expansion coefficients. The motivation of this present work is to further understand the fundamental of the effect of Sr doing on the oxygen reduction reaction (ORR) kinetics of LNO cathode. Porous symmetrical cells of La2-xSrxNiO4+delta (0≤x≤0.4) were fabricated and characterized by electrochemical impedance spectroscopy (EIS) in different PO2 from temperature range of 600˜800°C. The spectra were analyzed based on the impedance model introduced by Adler et al. The rate determining steps (RDS) for ORR were proposed and the responsible reasons were discussed. The overall polarization resistances of doped samples increase with Sr level. Surface oxygen exchange and bulk ionic diffusion co-control the ORR kinetics. With high Sr content (x=0.3, 0.4), oxygen ion transfer resistance between nickelate/electrolyte is observed. However for porous symmetrical cells it is hard to associate the resistance from EIS directly to each ORR elementary processes because of the difficulty in describing the microstructure of the porous electrode. The dense electrode configuration was adopted in this thesis. By using the dense electrode, the surface area, the thickness of electrode, the interface between electrode and electrolyte and lastly the 3PB are theoretically well-defined. Through this method, there is a good chance to distinguish the contribution of surface exchange from other processes. Dense and thin electrode layers in thickness of ˜40 mum are fabricated by using a novel spray modified pressing method. Negligible

  17. Comparative effect of intraoperative propacetamol versus placebo on morphine consumption after elective reduction mammoplasty under remifentanil-based anesthesia: a randomized control trial [ISRCTN71723173].

    PubMed

    Binhas, Michèle; Decailliot, François; Rezaiguia-Delclaux, Saïda; Suen, Powen; Dumerat, Marc; François, Véronique; Combes, Xavier; Duvaldestin, Philippe

    2004-09-14

    BACKGROUND: Postoperative administration of paracetamol or its prodrug propacetamol has been shown to decrease pain with a morphine sparing effect. However, the effect of propacetamol administered intra-operatively on post-operative pain and early postoperative morphine consumption has not been clearly evaluated. In order to evaluate the effectiveness of analgesic protocols in the management of post-operative pain, a standardized anesthesia protocol without long-acting opioids is crucial. Thus, for ethical reasons, the surgical procedure under general anesthesia with remifentanil as the only intraoperative analgesic must be associated with a moderate predictable postoperative pain. METHODS: We were interested in determining the postoperative effect of propacetamol administered intraoperatively after intraoperative remifentanil. Thirty-six adult women undergoing mammoplasty with remifentanil-based anesthesia were randomly assigned to receive propacetamol 2 g or placebo one hour before the end of surgery. After remifentanil interruption and tracheal extubation in recovery room, pain was assessed and intravenous titrated morphine was given. The primary end-point was the cumulative dose of morphine administered in the recovery room. The secondary end-points were the pain score after tracheal extubation and one hour after, the delay for obtaining a Simplified Numerical Pain Scale (SNPS) less than 4, and the incidence of morphine side effects in the recovery room.For intergroup comparisons, categorical variables were compared using the chi-squared test and continuous variables were compared using the Student t test or Mann-Whitney U test, as appropriate. A p value less than 0.05 was considered as significant. RESULTS: In recovery room, morphine consumption was lower in the propacetamol group than in the placebo group (p = 0.01). Pain scores were similar in both groups after tracheal extubation and lower in the propacetamol group (p = 0.003) one hour after tracheal

  18. Reduction of Argon Consumption to Less than 2 L min(-1) by Gas Recycling in Inductively Coupled Plasma Optical Emission Spectrometry.

    PubMed

    Tirk, Paul; Wolfgang, Matthias; Wiltsche, Helmar

    2016-07-19

    An innovative interface between the torch and the entrance optics for inductively coupled plasma optical emission spectrometry (ICP-OES) is proposed. This system is capable of collecting all argon which was initially supplied to the torch, cooling and cleaning it and feeding most of the argon back to the outer gas port of the torch. Thereby, the total argon consumption could be reduced from 14 to 1.4 L min(-1) using a standard torch and without restricting the rf power. The excitation- and rotational temperature of the plasma were identical when comparing the traditional setup with the enclosed plasma interface. However, the limits of detection (LOD) and limits of quantification (LOQ) of 27 elements investigated were degraded about 5-fold, though this fact can be expected to stem from a change of the observed zone in the plasma caused by the slight overpressure of 2000 Pa within the interface. Though the enclosed plasma interface was located close to the load coil, the rf power coupled to the interface was well below 1 W and no rf arcing was observed for two different rf generator designs. PMID:27306111

  19. High-Potential Electrocatalytic O2 Reduction with Nitroxyl / NOx Mediators: Implications for Fuel Cells and Aerobic Oxidation Catalysis

    SciTech Connect

    Gerken, James B.; Stahl, Shannon S.

    2015-07-15

    Efficient reduction of O2 to water is a central challenge in energy conversion and aerobic oxidation catalysis. In the present study, we investigate the electrochemical reduction of O2 with soluble organic nitroxyl and nitrogen oxide (NOx) mediators. When used alone, neither organic nitroxyls, such as TEMPO (2,2,6,6-tetramethyl-1-piperidinyl-N-oxyl), nor NOx species, such as sodium nitrite, are effective mediators of electrochemical O2 reduction. The combination of nitroxyl/NOx species, however, mediates sustained O2 reduction at electrochemical potentials of 0.19–0.33 V (vs. Fc/Fc+) in acetonitrile containing trifluoroacetic acid. Mechanistic analysis of the coupled redox reactions supports a process in which the nitrogen oxide catalyst drives aerobic oxidation of a nitroxyl mediator to an oxoammonium species, which then is reduced back to the nitroxyl at the cathode. The electrolysis potential is dictated by the oxoammonium/nitroxyl reduction potential. The high potentials observed with this ORR system benefit from the mechanism-based specificity for four-electron reduction of oxygen to water mediated by NOx species, together with kinetically efficient reduction of oxidized NOx species by TEMPO and other organic nitroxyls. This research was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center, funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences.

  20. Ultra-low Sulfur Reduction Emission Control Device/Development of an On-board Fuel Sulfur Trap

    SciTech Connect

    Rohrbach, Ron; Barron, Ann

    2008-07-31

    Honeywell has completed working on a multiyear program to develop and demonstrate proof-of-concept for an 'on-vehicle' desulfurization fuel filter for both light duty and heavy-duty diesel engines. Integration of the filter into the vehicle fuel system will reduce the adverse effects sulfur has on post combustion emission control devices such as NOx adsorbers. The NOx adsorber may be required to meet the proposed new EPA Tier II and '2007-Rule' emission standards. The proposed filter concept is based on Honeywell's reactive filtration technology and experience in liquids handling and conditioning. A regeneration and recycling plan for the spent filters was also examined. We have chosen to develop and demonstrate this technology based on criteria set forth for a heavy duty CIDI engine system because it represents a more challenging set of conditions of service intervals and overall fuel usage over light duty systems. In the second phase of the program a light duty diesel engine test was also demonstrated. Further, technology developed under this proposal would also have application for the use of liquid based fuels for fuel cell power generation. The program consisted of four phases. Phase I focused on developing a concept design and analysis and resolution of technical barriers concerning removal of sulfur-containing species in low sulfur fuels. In Phase II concentrated on prototype filter design and preparation followed by qualification testing of this component in a fuel line application. Phase III studied life cycle and regeneration options for the spent filter. Phase IV focused on efficacy and benefits in the desulfation steps of a NOx adsorber on both a heavy and light duty engine. The project team included a number of partners, with Honeywell International as the prime contractor. The partners include an emission control technology developer (Honeywell International), a fuel technology developer (Marathon Ashland Petroleum), a catalyst technology developer

  1. Th1/Th17 Cell Induction and Corresponding Reduction in ATP Consumption following Vaccination with the Novel Mycobacterium tuberculosis Vaccine MVA85A

    PubMed Central

    Griffiths, Kristin L.; Pathan, Ansar A.; Minassian, Angela M.; Sander, Clare R.; Beveridge, Natalie E. R.; Hill, Adrian V. S.; Fletcher, Helen A.; McShane, Helen

    2011-01-01

    Vaccination with Bacille Calmette-Guérin (BCG) has traditionally been used for protection against disease caused by the bacterium Mycobacterium tuberculosis (M.tb). The efficacy of BCG, especially against pulmonary tuberculosis (TB) is variable. The best protection is conferred in temperate climates and there is close to zero protection in many tropical areas with a high prevalence of both tuberculous and non-tuberculous mycobacterial species. Although interferon (IFN)-γ is known to be important in protection against TB disease, data is emerging on a possible role for interleukin (IL)-17 as a key cytokine in both murine and bovine TB vaccine studies, as well as in humans. Modified Vaccinia virus Ankara expressing Antigen 85A (MVA85A) is a novel TB vaccine designed to enhance responses induced by BCG. Antigen-specific IFN-γ production has already been shown to peak one week post-MVA85A vaccination, and an inverse relationship between IL-17-producing cells and regulatory T cells expressing the ectonucleosidease CD39, which metabolises pro-inflammatory extracellular ATP has previously been described. This paper explores this relationship and finds that consumption of extracellular ATP by peripheral blood mononuclear cells from MVA85A-vaccinated subjects drops two weeks post-vaccination, corresponding to a drop in the percentage of a regulatory T cell subset expressing the ectonucleosidase CD39. Also at this time point, we report a peak in co-production of IL-17 and IFN-γ by CD4+ T cells. These results suggest a relationship between extracellular ATP and effector responses and unveil a possible pathway that could be targeted during vaccine design. PMID:21887254

  2. High-Potential Electrocatalytic O2 Reduction with Nitroxyl/NOx Mediators: Implications for Fuel Cells and Aerobic Oxidation Catalysis

    PubMed Central

    2015-01-01

    Efficient reduction of O2 to water is a central challenge in energy conversion and many aerobic oxidation reactions. Here, we show that the electrochemical oxygen reduction reaction (ORR) can be achieved at high potentials by using soluble organic nitroxyl and nitrogen oxide (NOx) mediators. When used alone, neither organic nitroxyls, such as 2,2,6,6-tetramethyl-1-piperidinyl-N-oxyl (TEMPO), nor NOx species, such as sodium nitrite, are effective ORR mediators. The combination of nitroxyl/NOx species, however, mediates sustained O2 reduction with overpotentials as low as 300 mV in acetonitrile containing trifluoroacetic acid. Mechanistic analysis of the coupled redox reactions supports a process in which the nitrogen oxide catalyst drives aerobic oxidation of a nitroxyl mediator to an oxoammonium species, which then is reduced back to the nitroxyl at the cathode. The electrolysis potential is dictated by the oxoammonium/nitroxyl reduction potential. The overpotentials accessible with this ORR system are significantly lower than widely studied molecular metal-macrocycle ORR catalysts and benefit from the mechanism-based specificity for four-electron reduction of oxygen to water mediated by NOx species, together with kinetically efficient reduction of oxidized NOx species by TEMPO and other organic nitroxyls. PMID:27162977

  3. Pain Reduction and Improvement in Range of Motion After Daily Consumption of an Açai (Euterpe oleracea Mart.) Pulp–Fortified Polyphenolic-Rich Fruit and Berry Juice Blend

    PubMed Central

    Ager, David M.; Redman, Kimberlee A.; Mitzner, Marcie A.; Benson, Kathleen F.; Schauss, Alexander G.

    2011-01-01

    Abstract Dietary interventions involving antioxidants are of interest for reducing inflammation, improving joint motion, and altering pain perception. We evaluated the effect of oral consumption of a fruit and berry blend on pain and range of motion (ROM). This open-label clinical pilot study involved 14 study participants with limitations in ROM that was associated with pain and affected daily living. Participants included but were not limited to those with age-related osteoarthritis. Study participants consumed 120 mL MonaVie Active® fruit juice, predominantly containing açai pulp (Euterpe oleracea Mart.) and other fruit concentrates, daily for 12 weeks. Study participants were assessed at baseline and 2, 4, 8, and 12 weeks by structured nurse interviews, pain and activities of daily living (ADL) questionnaires, blood samples, and ROM assessment. Pain was scored by using a visual analogue scale. ROM was assessed by using dual digital inclinometry as recommended by American Medical Association guidelines. Consumption of the juice resulted in significant pain reduction, improved ROM measures, and improvement in ADLs. Serum antioxidant status, as monitored by the cell-based antioxidant protection in erythrocytes (CAP-e) assay, was improved within 2 weeks and continued to improve throughout the 12 weeks of study participation (P<.01). The inflammatory marker C-reactive protein was reduced at 12 weeks, but this change did not reach statistical significance. Lipid peroxidation decreased mildly at 12 weeks. The antioxidant status, as measured by the CAP-e bioassay, showed the best correlation with improvements in physical well-being (pain, ROM, and ADL). The significant association among increased antioxidant status, improved ROM, and pain reduction warrants further study. PMID:21470042

  4. Motor vehicle fuel economy, the forgotten HC control stragegy?

    SciTech Connect

    Deluchi, M.; Wang, Quanlu; Greene, D.L.

    1992-06-01

    Emissions of hydrocarbons from motor vehicles are recognized as major contributors to ozone pollution in urban areas. Petroleum-based motor fuels contain volatile organic compounds (VOC) which, together with oxides of nitrogen, promote the formation of ozone in the troposphere via complex photochemical reactions. VOC emissions from the tailpipe and evaporation from the fuel and engine systems of highway vehicles are believed to account for about 40% of total VOC emissions in any region. But motor fuels also generate emissions throughout the fuel cycle, from crude oil production to refining, storage, transportation, and handling, that can make significant contributions to the total inventory of VOC emissions. Many of these sources of emissions are directly related to the quantity of fuel produced and handled throughout the fuel cycle. It is, therefore, reasonable to expect that a reduction in total fuel throughput might result in a reduction of VOC emissions. In particular, reducing vehicle fuel consumption by increasing vehicle fuel economy should reduce total fuel throughput, thereby cutting total emissions of VOCS. In this report we identify the sources of VOC emissions throughout the motor fuel cycle, quantify them to the extent possible, and describe their dependence on automobile and light truck fuel economy.

  5. Lean consumption.

    PubMed

    Womack, James P; Jones, Daniel T

    2005-03-01

    During the past 20 years, the real price of most consumer goods has fallen worldwide, the variety of goods and the range of sales channels offering them have continued to grow, and product quality has steadily improved. So why is consumption often so frustrating? It doesn't have to be--and shouldn't be--the authors say. They argue that it's time to apply lean thinking to the processes of consumption--to give consumers the full value they want from goods and services with the greatest efficiency and the least pain. Companies may think they save time and money by off-loading work to the consumer but, in fact, the opposite is true. By streamlining their systems for providing goods and services, and by making it easier for customers to buy and use those products and services, a growing number of companies are actually lowering costs while saving everyone time. In the process, these businesses are learning more about their customers, strengthening consumer loyalty, and attracting new customers who are defecting from less user-friendly competitors. The challenge lies with the retailers, service providers, manufacturers, and suppliers that are not used to looking at total cost from the standpoint of the consumer and even less accustomed to working with customers to optimize the consumption process. Lean consumption requires a fundamental shift in the way companies think about the relationship between provision and consumption, and the role their customers play in these processes. It also requires consumers to change the nature of their relationships with the companies they patronize. Lean production has clearly triumphed over similar obstacles in recent years to become the dominant global manufacturing model. Lean consumption, its logical companion, can't be far behind. PMID:15768676

  6. A role of hydrocarbon reaction for NO{sub x} formation and reduction in fuel-rich pulverized coal combustion

    SciTech Connect

    Taniguchi, Masayuki; Kamikawa, Yuki; Okazaki, Teruyuki; Yamamoto, Kenji; Orita, Hisayuki

    2010-08-15

    We have investigated an index for modeling a NO{sub x} reaction mechanism of pulverized coal combustion. The reaction mechanism of coal nitrogen was examined by drop-tube furnace experiments under various burning conditions. We proposed the gas phase stoichiometric ratio (SRgas) as a key index to evaluate NO{sub x} concentration in fuel-rich flames. The SRgas was defined as: SRgas {identical_to} amount of fuel required for stoichiometry combustion/amount of gasified fuel where, the amount of gasified fuel was defined as the amount of fuel which had been released to the gas phase by pyrolysis, oxidation and gasification reactions. When SRgas < 1.0, NO{sub x} concentration was strongly influenced by the value of SRgas. In this condition, the NO{sub x} concentration was hardly influenced by coal type, particle diameter, or reaction time. We developed a model to analyze NO{sub x} and XN(HCN, NH{sub 3}) concentrations for pulverized coal/air combustion and coal/CO{sub 2}/O{sub 2} combustion, based on the index. NO{sub x} and XN concentrations did not reproduce the experimental results without considering reactions between hydrocarbons and NO{sub x}. The hydrocarbon reaction was important for both NO{sub x} and XN, especially for air combustion. In the present model, an empirical formula was used to estimate the total concentration of hydrocarbons in coal flame. The reaction of heavy hydrocarbons which had plural aromatic rings was very important to analyze the reaction mechanism of hydrocarbons for coal combustion in detail. When burning temperature and SRgas were the same, total hydrocarbon concentration in a coal flame was larger than that of a light gaseous hydrocarbon flame. Total hydrocarbon concentration in oxy-fuel combustion was lower than that in air combustion. We verified the proposed model by experimental results obtained for a drop-tube furnace and a laboratory-scale furnace that had an installed low-NO{sub x} burner. (author)

  7. Effect of cationic molecules on the oxygen reduction reaction on fuel cell grade Pt/C (20 wt%) catalyst in potassium hydroxide (aq, 1 mol dm(-3)).

    PubMed

    Ong, Ai Lien; Inglis, Kenneth K; Whelligan, Daniel K; Murphy, Sam; Varcoe, John R

    2015-05-14

    This study investigates the effect of 1 mmol dm(-3) concentrations of a selection of small cationic molecules on the performance of a fuel cell grade oxygen reduction reaction (ORR) catalyst (Johnson Matthey HiSPEC 3000, 20 mass% Pt/C) in aqueous KOH (1 mol dm(-3)). The cationic molecules studied include quaternary ammonium (including those based on bicyclic systems) and imidazolium types as well as a phosphonium example: these serve as fully solubilised models for the commonly encountered head-groups in alkaline anion-exchange membranes (AAEM) and anion-exchange ionomers (AEI) that are being developed for application in alkaline polymer electrolyte fuel cells (APEFCs), batteries and electrolysers. Both cyclic and hydrodynamic linear sweep rotating disk electrode voltammetry techniques were used. The resulting voltammograms and subsequently derived data (e.g. apparent electrochemical active surface areas, Tafel plots, and number of [reduction] electrons transferred per O2) were compared. The results show that the imidazolium examples produced the highest level of interference towards the ORR on the Pt/C catalyst under the experimental conditions used. PMID:25877304

  8. Facile one-pot synthesis of platinum nanoparticles decorated nitrogen-graphene with high electrocatalytic performance for oxygen reduction and anodic fuels oxidation

    NASA Astrophysics Data System (ADS)

    Navaee, Aso; Salimi, Abdollah; Soltanian, Saeid; Servati, Peyman

    2015-03-01

    Due to exceptional electronic properties of graphene (Gr) and nitrogen doped graphene (N-Gr), they are considered as superior supporting platforms for novel metal nanoparticle decorations. Here, we report, a novel one-step electrochemical method for synthesis of Nitrogen-doped graphene sheets uniformly decorated with platinum nanoparticles (Pt/N-Gr). A graphite rod and platinum wire are respectively used for graphene and platinum nanoparticles production. The potential is cycled from -3V to +3V in acetonitrile solution as a nitrogen dopant source. By increasing the number of cycles the nitrogen-doped graphene/platinum nanoparticles composite is generated. After heat-treating the composite is characterized with various techniques such as FTIR, Raman, XPS, SEM and TEM. The electrocatalytic activity of the prepared composite toward the reduction of O2 and the oxidation of usual anodic fuels such as methanol, ethanol, hydrazine and formic acid is investigated using cyclic voltammetry technique. In comparison to commercial platinum/carbon, the onset potentials and the current densities for both O2 reduction and fuels oxidation are remarkably improved. Furthermore, the modified electrode by this composite shows good long-term stability and poisoning tolerance.

  9. Photocatalytic generation of solar fuels from the reduction of H2O and CO2: a look at the patent literature.

    PubMed

    Protti, Stefano; Albini, Angelo; Serpone, Nick

    2014-10-01

    The application of photocatalysis in environment remediation as well as in the generation of useful fuels from the reduction of water (hydrogen) and of carbon dioxide (methanol, carbon monoxide and/or methane) has been investigated largely in the last four decades. A significant part (12-13%) of the literature on the generation of such fuels is found in patents. Accordingly, the present article presents a selection of the patent literature on the theme. Photocatalysts, whether pure or doped, solid solutions or composites, reported in patents are reviewed along with the corresponding preparative methods and the photocatalytic performance. The absorption of light by such materials has been extended toward the red side of the spectrum, so that a better use of solar irradiation has been obtained, but the expected improvement of the catalytic effect has not always been achieved. The causes of these results and the way for improving the performance in the various steps of the process (e.g. avoiding charge recombination or catalyst corrosion) have been documented. The correct use of the term water splitting and the fundamentals of photochemical hydrogen evolution in the presence of a sacrificial electron donor (e.g., alcohols) are discussed. Quantitative data about the amount of hydrogen evolved or carbon-based fuels produced are indicated whenever available. PMID:25135433

  10. LWR spent fuel reduction by the removal of U and the compact storage of Pu with FP for long-term nuclear sustainability

    SciTech Connect

    Fukasawa, T.; Hoshino, K.; Takano, M.; Sato, S.; Shimazu, Y.

    2013-07-01

    Fast breeder reactors (FBR) nuclear fuel cycle is needed for long-term nuclear sustainability while preventing global warming and maximum utilizing the limited uranium (U) resources. The 'Framework for Nuclear Energy Policy' by the Japanese government on October 2005 stated that commercial FBR deployment will start around 2050 under its suitable conditions by the successive replacement of light water reactors (LWR) to FBR. Even after Fukushima Daiichi Nuclear Power Plant accident which made Japanese tendency slow down the nuclear power generation activities, Japan should have various options for energy resources including nuclear, and also consider the delay of FBR deployment and increase of LWR spent fuel (LWR-SF) storage amounts. As plutonium (Pu) for FBR deployment will be supplied from LWR-SF reprocessing and Japan will not possess surplus Pu, the authors have developed the flexible fuel cycle initiative (FFCI) for the transition from LWR to FBR. The FFCI system is based on the possibility to stored recycled materials (U, Pu)temporarily for a suitable period according to the FBR deployment rate to control the Pu demand/supply balance. This FFCI system is also effective after the Fukushima accident for the reduction of LWR-SF and future LWR-to-FBR transition. (authors)

  11. Resolving Past Liabilities for Future Reduction in Greenhouse Gases; Nuclear Energy and the Outstanding Federal Liability of Spent Nuclear Fuel

    NASA Astrophysics Data System (ADS)

    Donohue, Jay

    This thesis will: (1) examine the current state of nuclear power in the U.S.; (2) provide a comparison of nuclear power to both existing alternative/renewable sources of energy as well as fossil fuels; (3) dissect Standard Contracts created pursuant to the National Waste Policy Act (NWPA), Congress' attempt to find a solution for Spent Nuclear Fuel (SNF), and the designation of Yucca Mountain as a repository; (4) the anticipated failure of Yucca Mountain; (5) explore WIPP as well as attempts to build a facility on Native American land in Utah; (6) examine reprocessing as a solution for SNF used by France and Japan; and, finally, (7) propose a solution to reduce GHG's by developing new nuclear energy plants with financial support from the U.S. government and a solution to build a storage facility for SNF through the sitting of a repository based on a "bottom-up" cooperative federalism approach.

  12. Implementation of fuel-cost reduction measures in Costa Rican private bus and taxi fleets. Final report

    SciTech Connect

    Not Available

    1986-06-11

    The project focused on demonstrations of fuel-conservation measures in private bus and taxi fleets and a public information and awareness campaign. In Costa Rica, buses and taxis tend to be grouped into cooperatives and umbrella associations that provide convenient host organizations for such a project. The demonstrations were of a practical nature, and featured proven measures that would produce significant savings under actual operating conditions.

  13. The carbon reduction research of teaching staff commuting aided by Google Earth: taking Guangzhou University as an example

    NASA Astrophysics Data System (ADS)

    Xie, Hongyu; Wang, Xixiang; Zhao, Meichan; Zhao, Huaqing; Lin, Zhien

    2008-10-01

    In this paper, taking Guangzhou University as an example, carbon reduction of teaching staff commuting was researched. Firstly, considering carbon emission of teaching staff commuting is come from the fuel consumption of vehicle used to trip, the routes, schedule, vehicle type, fuel type and fuel consumption per 100 km of service express bus, public bus and private car were investigated from relevant department and web questionnaire in office automation system. Secondly, the routes of service express bus, public bus and private car were drawn in Google earth browser to measure distance. Thirdly, combined the bus schedule, school calendar, curriculum timetable of teacher and fuel consumption per 100 km of all kinds of vehicle, the fuel consumption of service express bus, public bus and private car were computed. Fourthly, carbon emission was calculated according to net calorific factor and calorie carbon emission factors of fuel. Finally, the measures of carbon reduction were discussed. The research results show that teaching staff commuting emitted 455.433 tons carbon in 2005-2006 academic year. And reducing usage rate of private car and adding new service express bus line are efficient measure of carbon reduction. Former measure can reduce 33.6891 tons carbon and about 7.4% of original emission. The latter can reduce 7.6317 tons and about 1.68% of original emission.

  14. Consumption bomb.

    PubMed

    Harrison, P

    1999-01-01

    This article focuses on the issue of consumption in relation to the growing world population. Over the past 25 years, world population increased by 53%, while world consumption per person increased by only 39%. If consumption continues to grow at 1.4%, the world consumption per person will rise by 100% over the next 50 years with the population increasing by only half that amount. The burden of reducing the environmental impact brought about by this increase lies on technology. Technology needs to deliver major changes in improving resource productivity, and decreasing the amount of waste created. Productivity such as global food production has kept up with demand. Malnutrition persists due to poverty, and not because of the inability of the world to produce enough food. However, the prospects are much worse for resources that are not traded on markets or subject to sustainable management such as groundwater, state forests, ocean fish, and communal waste sinks like rivers, lakes, and the global atmosphere. These resources are not under the direct control of people affected by shortage. People who want to change the way these resources are used or managed have to pass through the legal or political system. Usually, political responses are slow and there has to be a very widespread environmental damage before action is taken. PMID:12295543

  15. Reduction of carbon dioxide gas formation at the anode of a direct methanol fuel cell using chemically enhanced solubility

    NASA Astrophysics Data System (ADS)

    Lundin, Michael D.; McCready, Mark J.

    The production of CO 2 gas at the DMFC anode leads to dramatic increases in pumping power requirements and reduced power output because of mass transfer limitations as bubble trains form in the channels of larger stacks. Experimental observations taken in a 5 cm 2 DMFC test cell operated at 60 °C, 1 atm, and with a methanol/water fuel flow rates of 5-10 cm 3 min -1 indicate that the rate of bubble formation can be reduced by increasing the fuel flow because more liquid is available for the CO 2 to dissolve in. Further observations indicate that KOH and LiOH added to the fuel eliminates CO 2 gas formation in situ at low concentrations because of the greatly increased solubility that results. A mathematical model for the volumetric rate of CO 2 gas production that includes effects of temperature and solubility is developed and extended to include the effects of hydroxide ions in solution. The model is used to predict the onset location of gas formation in the flow field as well as the void fraction at any point in the flow field. Predictions from the model agree very well with our experiments. Model predictions explain differences in the initial location of bubble formation for fuel solutions pre-saturated with CO 2 as opposed to CO 2-free solutions. Experiments with KOH and LiOH added to fuel solutions confirm the validity of the model extension that includes solubility that is enhanced by chemical reaction. Experiments with LiOH, KOH, and ammonium hydroxide show that the long-term durability of standard Pt-Ru/Nafion ®/Pt membrane electrode assemblies is compromised because of the presence of lithium, potassium, and ammonium cations that interact with the Nafion ® membrane and result in increasing the ohmic limitations of the polymer electrolyte membrane. Experiments with Ca(OH) 2, while reducing gas formation, precipitate the product CaCO 3 out of solution too rapidly for downstream filtering, blocking channels in the flow field.

  16. Oxygen reduction reaction catalyzed by platinum nanonetwork prepared by template free one step synthesis for polymer electrolyte membrane fuel cells

    SciTech Connect

    Narayanamoorthy, B.; Kumar, B.V.V.S. Pavan; Eswaramoorthy, M.; Balaji, S.

    2014-07-01

    Highlights: • Supportless Pt nanonetwork (Pt NN) synthesized by novel template free one step method as per our earlier reported procedure. • Electrocatalytic activity of Pt NN studied taking oxygen reduction reaction in acid medium. • Kinetic and thermodynamic parameters were deduced under hydrodynamic conditions. • ORR mechanistic pathway was proposed based on kinetic rate constants. • ADT analysis found enhanced stability (5000 cycles) for Pt NN than Pt NN/VC and reported Pt/C. - Abstract: The reduction reaction of molecular oxygen (ORR) was investigated using supportless Pt nanonetwork (Pt NN) electrocatalyst in sulfuric acid medium. Pt NN was prepared by template free borohydride reduction. The transmission electron microscope images revealed a network like nano-architecture having an average cluster size of 30 nm. The electrochemical characterization of supportless and Vulcan carbon supported Pt NN (Pt NN/VC) was carried out using rotating disc and ring disc electrodes at various temperatures. Kinetic and thermodynamic parameters were estimated under hydrodynamic conditions and compared with Pt NN/VC and reported Pt/C catalysts. The accelerated durability test revealed that supportless Pt NN is quite stable for 5000 potential cycles with 22% reduction in electrochemical surface area (ECSA). While the initial limiting current density has in fact increased by 11.6%, whereas Pt NN/VC suffered nearly 55% loss in ECSA and 13% loss in limiting current density confirming an enhanced stability of supportless Pt NN morphology for ORR compared to conventional Pt/C ORR catalysts in acid medium.

  17. Impact of electric cars on national energy consumption

    NASA Astrophysics Data System (ADS)

    Agarwal, P. D.

    1980-02-01

    Energy utilization of electric vehicles is discussed in terms of energy efficiency in comparison to internal combustion engine automobiles, starting from oil or coal as the prime energy source. It is found that although an electric car does not save primary energy resources, it can transfer some of the transportation fuel needs from petroleum to coal, nuclear, or hydropower. With reference to the impact of electric vehicles on reduction of petroleum consumption, it is shown that the dependence of the United States on foreign oil can be reduced much more quickly and at much lower cost by converting electric utility boilers from oil to coal.

  18. Effects of various organic carbon sources on simultaneous V(V) reduction and bioelectricity generation in single chamber microbial fuel cells.

    PubMed

    Hao, Liting; Zhang, Baogang; Cheng, Ming; Feng, Chuanping

    2016-02-01

    Four ordinary carbon sources affecting V(V) reduction and bioelectricity generation in single chamber microbial fuel cells (MFCs) were investigated. Acetate supported highest maximum power density of 589.1mW/m(2), with highest V(V) removal efficiency of 77.6% during 12h operation, compared with glucose, citrate and soluble starch. Exorbitant initial V(V) concentration led to lower V(V) removal efficiencies and power outputs. Extra addition of organics had little effect on the improvement of MFCs performance. V(V) reduction and bioelectricity generation were enhanced and then suppressed by the increase of conductivity. The larger the external resistance, the higher the V(V) removal efficiencies and voltage outputs. High-throughput 16S rRNA gene pyrosequencing analysis implied the accumulation of Enterobacter which had the capabilities of V(V) reduction, electrochemical activity and fermentation, accompanied with other functional species as Pseudomonas, Spirochaeta, Sedimentibacter and Dysgonomonas. This study steps forward to remediate V(V) contaminated environment based on MFC technology. PMID:26642216

  19. Unveiling N-protonation and anion-binding effects on Fe/N/C-catalysts for O2 reduction in PEM fuel cells

    PubMed Central

    Herranz, Juan; Jaouen, Frédéric; Lefèvre, Michel; Kramm, Ulrike I.; Proietti, Eric; Dodelet, Jean-Pol; Bogdanoff, Peter; Fiechter, Sebastian; Abs-Wurmbach, Irmgard; Bertrand, Patrick; Arruda, Thomas M.; Mukerjee, Sanjeev

    2013-01-01

    The high cost of proton-exchange-membrane fuel cells would be considerably reduced if platinumbased catalysts were replaced by iron-based substitutes, which have recently demonstrated comparable activity for oxygen reduction, but whose cause of activity decay in acidic medium has been elusive. Here, we reveal that the activity of Fe/N/C-catalysts prepared through a pyrolysis in NH3 is mostly imparted by acid-resistant FeN4-sites whose turnover frequency for the O2 reduction can be regulated by fine chemical changes of the catalyst surface. We show that surface N-groups protonate at pH 1 and subsequently bind anions. This results in decreased activity for the O2 reduction. The anions can be removed chemically or thermally, which restores the activity of acid-resistant FeN4-sites. These results are interpreted as an increased turnover frequency of FeN4-sites when specific surface N-groups protonate. These unprecedented findings provide new perspective for stabilizing the most active Fe/N/C-catalysts known to date. PMID:24179561

  20. Improvement of activated carbons as oxygen reduction catalysts in neutral solutions by ammonia gas treatment and their performance in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Watson, Valerie J.; Nieto Delgado, Cesar; Logan, Bruce E.

    2013-11-01

    Commercially available activated carbon (AC) powders from different precursor materials (peat, coconut shell, coal, and hardwood) were treated with ammonia gas at 700 °C to improve their performance as oxygen reduction catalysts in neutral pH solutions used in microbial fuel cells (MFCs). The ammonia treated ACs exhibited better catalytic performance in rotating ring-disk electrode tests than their untreated precursors, with the bituminous based AC most improved, with an onset potential of Eonset = 0.12 V (untreated, Eonset = 0.08 V) and n = 3.9 electrons transferred in oxygen reduction (untreated, n = 3.6), and the hardwood based AC (treated, Eonset = 0.03 V, n = 3.3; untreated, Eonset = -0.04 V, n = 3.0). Ammonia treatment decreased oxygen content by 29-58%, increased nitrogen content to 1.8 atomic %, and increased the basicity of the bituminous, peat, and hardwood ACs. The treated coal based AC cathodes had higher maximum power densities in MFCs (2450 ± 40 mW m-2) than the other AC cathodes or a Pt/C cathode (2100 ± 1 mW m-2). These results show that reduced oxygen abundance and increased nitrogen functionalities on the AC surface can increase catalytic performance for oxygen reduction in neutral media.

  1. Changes in the Healthy Beverage Index in Response to an Intervention Targeting a Reduction in Sugar-Sweetened Beverage Consumption as Compared to an Intervention Targeting Improvements in Physical Activity: Results from the Talking Health Trial

    PubMed Central

    Hedrick, Valisa E.; Davy, Brenda M.; Myers, Emily A.; You, Wen; Zoellner, Jamie M.

    2015-01-01

    The recently developed Healthy Beverage Index (HBI) was designed to evaluate overall beverage intake quality (including total fluid consumption and beverage calories), yet no known intervention studies have assessed longitudinal changes to the HBI. The objective of this investigation was to assess changes in HBI scores in response to a sugar-sweetened beverage (SSB) reduction trial as compared to a physical activity comparison group. Participants were enrolled into a six-month, community-based, controlled behavioral trial and randomized into either a SSB reduction group (SIPsmartER) or a physical activity group (MoveMore). Correlations and multilevel mixed-effects linear regression with intention-to-treat analyses are presented. Total HBI score significantly increased for SIPsmartER (n = 149) (mean increase = 7.5 points (5.4, 9.7), p ≤ 0.001) and MoveMore (n = 143) (mean increase = 3.4 points (1.6, 5.2), p ≤ 0.001) participants, with a significant between group effect (p ≤ 0.05), over the six-month intervention. Other significant changes in HBI components for SIPsmartER included increased SSB and total beverage calorie scores, and decreased low-fat milk and diet soda scores. Changes in total HBI scores were significantly correlated with changes in total Healthy Eating Index-2010 scores (r = 0.15, p ≤ 0.01). Our findings suggest that individual HBI component scores, beyond the SSB component, are influenced by intervention strategies that primarily focus on SSB reduction. PMID:26690208

  2. Changes in the Healthy Beverage Index in Response to an Intervention Targeting a Reduction in Sugar-Sweetened Beverage Consumption as Compared to an Intervention Targeting Improvements in Physical Activity: Results from the Talking Health Trial.

    PubMed

    Hedrick, Valisa E; Davy, Brenda M; Myers, Emily A; You, Wen; Zoellner, Jamie M

    2015-12-01

    The recently developed Healthy Beverage Index (HBI) was designed to evaluate overall beverage intake quality (including total fluid consumption and beverage calories), yet no known intervention studies have assessed longitudinal changes to the HBI. The objective of this investigation was to assess changes in HBI scores in response to a sugar-sweetened beverage (SSB) reduction trial as compared to a physical activity comparison group. Participants were enrolled into a six-month, community-based, controlled behavioral trial and randomized into either a SSB reduction group (SIPsmartER) or a physical activity group (MoveMore). Correlations and multilevel mixed-effects linear regression with intention-to-treat analyses are presented. Total HBI score significantly increased for SIPsmartER (n = 149) (mean increase = 7.5 points (5.4, 9.7), p ≤ 0.001) and MoveMore (n = 143) (mean increase = 3.4 points (1.6, 5.2), p ≤ 0.001) participants, with a significant between group effect (p ≤ 0.05), over the six-month intervention. Other significant changes in HBI components for SIPsmartER included increased SSB and total beverage calorie scores, and decreased low-fat milk and diet soda scores. Changes in total HBI scores were significantly correlated with changes in total Healthy Eating Index-2010 scores (r = 0.15, p ≤ 0.01). Our findings suggest that individual HBI component scores, beyond the SSB component, are influenced by intervention strategies that primarily focus on SSB reduction. PMID:26690208

  3. Lean mixture engine testing and evaluation program. [for automobile engine pollution and fuel performances

    NASA Technical Reports Server (NTRS)

    Dowdy, M. W.; Hoehn, F. W.; Griffin, D. C.

    1975-01-01

    Experimental results for fuel consumption and emissions are presented for a 350 CID (5.7 liter) Chevrolet V-8 engine modified for lean operation with gasoline. The lean burn engine achieved peak thermal efficiency at an equivalence ratio of 0.75 and a spark advance of 60 deg BTDC. At this condition the lean burn engine demonstrated a 10% reduction in brake specific fuel consumption compared with the stock engine; however, NOx and hydrocarbon emissions were higher. With the use of spark retard and/or slightly lower equivalence ratios, the NOx emissions performance of the stock engine was matched while showing a 6% reduction in brake specific fuel consumption. Hydrocarbon emissions exceeded the stock values in all cases. Diagnostic data indicate that lean performance in the engine configuration tested is limited by ignition delay, cycle-to-cycle pressure variations, and cylinder-to-cylinder distribution.

  4. Collegium on aviation fuel conservation efforts

    SciTech Connect

    Not Available

    1985-02-01

    Reduction in the consumption levels of fuel by Soviet civil aviation is addressed. Methods proposed to economize aircraft fuel include: the introduction of towing to the runup area, keeping aircraft surfaces in good condition by washing, ensuring the stability of engine operating characteristics by flushing out gas and air lines, using ground-based conditioners and equipment of ramps with ground-based sources of electricity to reduce the operation of auxiliary power plants, replacement of heat engines for clearing runways of snow and ice by the introduction of snowplows with blowers, introduction of machinery with infrared lighting, and broader application of chemical reagents.

  5. Caterpillar MorElectric DOE Idle Reduction Demonstration Program

    SciTech Connect

    John Bernardi

    2007-09-30

    This project titled 'Demonstration of the New MorElectric{trademark} Technology as an Idle Reduction Solution' is one of four demonstration projects awarded by the US Department of Energy in 2002. The goal of these demonstration and evaluation projects was to gather objective in-use information on the performance of available idle reduction technologies by characterizing the cost; fuel, maintenance, and engine life savings; payback; and user impressions of various systems and techniques. In brief, the Caterpillar Inc. project involved applying electrically driven accessories for cab comfort during engine-off stops and for reducing fuel consumption during on-highway operation. Caterpillar had equipped and operated five new trucks with the technology in conjunction with International Truck and Engine Corporation and COX Transfer. The most significant result of the project was a demonstrated average idle reduction of 13.8% for the 5 truck MEI fleet over the control fleet. It should be noted that the control fleet trucks were also equipped with an idle reduction device that would start and stop the main engine automatically in order to maintain cab temperature. The control fleet idle usage would have been reduced by 3858 hours over the 2 year period with the MEI system installed, or approximately 2315 gallons of fuel less (calculations assume a fuel consumption of 0.6 gallons per hour for the 13 liter engine at idle). The fuel saved will be significantly larger for higher displacement engines without idle reduction equipment such as the engine auto start/stop device used by COX Transfer. It is common for engines to consume 1.0 gallons per hour which would increase the fuel savings to approximately 1260 gallons per truck per year of typical idling (1800 hours idle/yr).

  6. Optimally Controlled Flexible Fuel Powertrain System

    SciTech Connect

    Duncan Sheppard; Bruce Woodrow; Paul Kilmurray; Simon Thwaite

    2011-06-30

    A multi phase program was undertaken with the stated goal of using advanced design and development tools to create a unique combination of existing technologies to create a powertrain system specification that allowed minimal increase of volumetric fuel consumption when operating on E85 relative to gasoline. Although on an energy basis gasoline / ethanol blends typically return similar fuel economy to straight gasoline, because of its lower energy density (gasoline ~ 31.8MJ/l and ethanol ~ 21.1MJ/l) the volume based fuel economy of gasoline / ethanol blends are typically considerably worse. This project was able to define an initial engine specification envelope, develop specific hardware for the application, and test that hardware in both single and multi-cylinder test engines to verify the ability of the specified powertrain to deliver reduced E85 fuel consumption. Finally, the results from the engine testing were used in a vehicle drive cycle analysis tool to define a final vehicle level fuel economy result. During the course of the project, it was identified that the technologies utilized to improve fuel economy on E85 also enabled improved fuel economy when operating on gasoline. However, the E85 fueled powertrain provided improved vehicle performance when compared to the gasoline fueled powertrain due to the improved high load performance of the E85 fuel. Relative to the baseline comparator engine and considering current market fuels, the volumetric fuel consumption penalty when running on E85 with the fully optimized project powertrain specification was reduced significantly. This result shows that alternative fuels can be utilized in high percentages while maintaining or improving vehicle performance and with minimal or positive impact on total cost of ownership to the end consumer. The justification for this project was two-fold. In order to reduce the US dependence on crude oil, much of which is imported, the US Environmental Protection Agency (EPA

  7. Effects of low concentration biodiesel blend application on modern passenger cars. Part 1: feedstock impact on regulated pollutants, fuel consumption and particle emissions.

    PubMed

    Fontaras, Georgios; Kousoulidou, Marina; Karavalakis, Georgios; Tzamkiozis, Theodoros; Pistikopoulos, Panayotis; Ntziachristos, Leonidas; Bakeas, Evangelos; Stournas, Stamoulis; Samaras, Zissis

    2010-05-01

    Five biodiesels from different feedstocks (rapeseed, soy, sunflower, palm, and used fried oils) blended with diesel at 10% vol. ratio (B10), were tested on a Euro 3 common-rail passenger car. Limited effects (-2% to +4%) were observed on CO(2) emissions. CO and HC emissions increased between 10% and 25% on average, except at high speed - high power where emissions were too low to draw conclusions. NOx emissions increased by up to 20% for two out of the five blends, decreased by up to 15% for two other blends, and remained unchanged for one blend. Particulate matter (PM) was reduced for all blends by up to 25% and the reductions were positively correlated with the extent of biodiesel saturation. PM reductions are associated with consistent reductions in non-volatile particle number. A variable behaviour in particle number is observed when volatile particles are also accounted. PMID:20080326

  8. N2O release from agro-biofuel production negates global warming reduction by replacing fossil fuels

    NASA Astrophysics Data System (ADS)

    Crutzen, P. J.; Mosier, A. R.; Smith, K. A.; Winiwarter, W.

    2008-01-01

    The relationship, on a global basis, between the amount of N fixed by chemical, biological or atmospheric processes entering the terrestrial biosphere, and the total emission of nitrous oxide (N2O), has been re-examined, using known global atmospheric removal rates and concentration growth of N2O as a proxy for overall emissions. For both the pre-industrial period and in recent times, after taking into account the large-scale changes in synthetic N fertiliser production, we find an overall conversion factor of 3-5% from newly fixed N to N2O-N. We assume the same factor to be valid for biofuel production systems. It is covered only in part by the default conversion factor for "direct" emissions from agricultural crop lands (1%) estimated by IPCC (2006), and the default factors for the "indirect" emissions (following volatilization/deposition and leaching/runoff of N: 0.35-0.45%) cited therein. However, as we show in the paper, when additional emissions included in the IPCC methodology, e.g. those from livestock production, are included, the total may not be inconsistent with that given by our "top-down" method. When the extra N2O emission from biofuel production is calculated in "CO2-equivalent" global warming terms, and compared with the quasi-cooling effect of "saving" emissions of fossil fuel derived CO2, the outcome is that the production of commonly used biofuels, such as biodiesel from rapeseed and bioethanol from corn (maize), depending on N fertilizer uptake efficiency by the plants, can contribute as much or more to global warming by N2O emissions than cooling by fossil fuel savings. Crops with less N demand, such as grasses and woody coppice species, have more favourable climate impacts. This analysis only considers the conversion of biomass to biofuel. It does not take into account the use of fossil fuel on the farms and for fertilizer and pesticide production, but it also neglects the production of useful co-products. Both factors partially compensate

  9. Porous nitrogen-doped carbon nanosheet on graphene as metal-free catalyst for oxygen reduction reaction in air-cathode microbial fuel cells.

    PubMed

    Wen, Qing; Wang, Shaoyun; Yan, Jun; Cong, Lijie; Chen, Ye; Xi, Hongyuan

    2014-02-01

    Porous nitrogen-doped carbon nanosheet on graphene (PNCN) was used as an alternative cathode catalyst for oxygen reduction reaction (ORR) in air-cathode microbial fuel cells (MFCs). Here we report a novel, low-cost, scalable, synthetic method for preparation of PNCN via the carbonization of graphite oxide-polyaniline hybrid (GO-PANI), subsequently followed by KOH activation treatment. Due to its high concentration of nitrogen and high specific surface area, PNCN exhibited an excellent catalytic activity for ORR. As a result, the maximum power density of 1159.34mWm(-2) obtained with PNCN catalyst was higher than that of Pt/C catalyst (858.49mWm(-2)) in a MFC. Therefore, porous nitrogen-doped carbon nanosheet could be a good alternative to Pt catalyst in MFCs. PMID:24239870

  10. Technical documentation for the Nonresidential-Buildings Energy-Consumption Survey: 1979-1980, building characteristics, energy end use and fuel oil tank data, public use data tapes. Users' guide

    SciTech Connect

    Not Available

    1982-02-01

    This document provides basic information and technical specifications necessary for using the machine-readable magnetic tapes containing the Building Characteristics, Energy End Use and Fuel Oil Tank data from the 1979-1980 Nonresidential Buildings Energy Consumption Survey (NBECS). Included in this document are a brief overview of the NBECS, technical specifications for reading the tapes and descriptions of the contents of each of the files contained on the tape. The remaining sections are devoted to technical topics of special interest to users of the data. Appended to this document are copies of the questionnaire used in the survey, a listing of the contents of the SPSS labels file, COBOL file description and TPL codebook. The results of the NBECS have been reported in a series of publications which are available to the public. A list of the reports currently available is included here as Appendix H.

  11. Jordanian industrial sector future energy consumption: Potential savings and environmental impact

    NASA Astrophysics Data System (ADS)

    Abdallat, Yousef; Al-Ghandoor, Ahmed; Salaymah, Mohammad

    2012-11-01

    This paper analyzes and evaluates impacts of introducing some efficient measures on the future fuel and electricity demands and associated reduction in GHG emissions. Without employing most effective energy conservation measures, energy demand is expected to rise by approximately 38% within 12 years time. Consequently, associated GHG emissions resulting from activities within the industrial sector are predicted to rise by 33% for the same period. However, if recommended energy management measures are implemented on a gradual basis, electricity and fuel consumptions as well as GHG emissions are forecasted to increase at a lower rate.

  12. Reduction of Pt2+ species in model Pt-CeO2 fuel cell catalysts upon reaction with methanol

    NASA Astrophysics Data System (ADS)

    Neitzel, Armin; Johánek, Viktor; Lykhach, Yaroslava; Skála, Tomáš; Tsud, Nataliya; Vorokhta, Mykhailo; Matolín, Vladimír; Libuda, Jörg

    2016-11-01

    The stability of atomically dispersed Pt2+ species on the surface of nanostructured CeO2 films during the reaction with methanol has been investigated by means of synchrotron radiation photoelectron spectroscopy and resonant photoemission spectroscopy. The isolated Pt2+ species were prepared at low Pt concentration in Pt-CeO2 film. Additionally, Pt2+ species coexisting with metallic Pt particles were prepared at high Pt concentration. We found that adsorption of methanol yields similar decomposition products regardless of Pt concentration in Pt-CeO2 films. A small number of oxygen vacancies formed during the methanol decomposition can be replenished in the Pt-CeO2 film with low Pt concentration by diffusion of oxygen from the bulk. In the presence of supported Pt particles, a higher number of oxygen vacancies leads to a partial reduction of the Pt2+ species. The isolated Pt2+ species are reduced under rather strongly reducing conditions only, i.e. during annealing under continuous exposure to methanol. Reduction of isolated Pt2+ species results in the formation of ultra-small Pt particles containing around 25 atoms per particle or less. Such ultra-small Pt particles demonstrate excellent stability against sintering during annealing of Pt-CeO2 film with low Pt concentration under reducing conditions.

  13. Oxygen reduction reaction increased tolerance and fuel cell performance of Pt and Ru xSe y onto oxide-carbon composites

    NASA Astrophysics Data System (ADS)

    Timperman, Laure; Gago, Aldo S.; Alonso-Vante, Nicolas

    Pt and Ru xSe y nanoparticles were selectively deposited onto oxide sites of oxide-carbon composite substrates using the photo-deposition process and compared to conventional carbon support materials. The oxide was essentially anatase phase. Cyclic voltammetry and rotating disk electrode measurements for the oxygen reduction reaction (ORR) in formic acid containing-electrolyte showed a tolerance improvement for ORR of Pt supported on composite substrates. This positive substrate effect on platinum, turned out not to be favorable for Ru xSe y catalyst centers. On the other hand, the methanol tolerance for ORR was increased for both nanostructured materials supported on the oxide-carbon composite. Single H 2/O 2 fuel cell results were in agreement with half-cell electrochemical measurements on Pt, showing an improvement of the power density when using the oxide-carbon as substrate for the cathode. The composites were evaluated as cathode catalysts of an HCOOH laminar-flow fuel cell (LFFC) in which commercial Pd/C was used as an anode catalyst. The cathodes with Ru xSe y and Pt supported on TiO 2/C improved the specific power density by 15% and 24%, respectively, with respect to carbon as support.

  14. Proton-beam driven fast ignition of inertially confined fuels: Reduction of the ignition energy by the use of two proton beams with radially shaped profiles

    SciTech Connect

    Temporal, M.; Honrubia, J. J.; Atzeni, S.

    2008-05-15

    Fast ignition of a spherical compressed deuterium-tritium assembly induced by the energy deposition of laser-accelerated proton beams is considered. An efficient way to reduce the ignition energy consists of using a two proton beams scheme [M. Temporal, Phys Plasmas 13, 122704 (2006)]. For a uniformly compressed fuel at 500 g/cm{sup 3} irradiated by proton beams with Maxwellian energy distribution with a temperature of 4 MeV, the ignition energy is 10 kJ using only one proton beam and reduces to a total of 8 kJ with the two-beam scheme. Further reduction of the ignition energy is found by using a first beam with annular radial profile and a second beam with the uniform radial profile. It is found that the first beam causes some additional fuel compression and confinement that decrease the total beam energy required for the ignition to 6 kJ, which is 40% smaller than in the case of a single beam with uniform radial profile.

  15. Nitrogen- and boron-co-doped core-shell carbon nanoparticles as efficient metal-free catalysts for oxygen reduction reactions in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Zhong, Shengkui; Zhou, Lihua; Wu, Ling; Tang, Lianfeng; He, Qiyi; Ahmed, Jalal

    2014-12-01

    The most severe bottleneck hindering the widespread application of fuel cell technologies is the difficulty in obtaining an inexpensive and abundant oxygen reduction reaction (ORR) catalyst. The concept of a heteroatom-doped carbon-based metal-free catalyst has recently attracted interest. In this study, a metal-free carbon nanoparticles-based catalyst hybridized with dual nitrogen and boron components was synthesized to catalyze the ORR in microbial fuel cells (MFCs). Multiple physical and chemical characterizations confirmed that the synthetic method enabled the incorporation of both nitrogen and boron dopants. The electrochemical measurements indicated that the co-existence of nitrogen and boron could enhance the ORR kinetics by reducing the overpotential and increasing the current density. The results from the kinetic studies indicated that the nitrogen and boron induced an oxygen adsorption mechanism and a four-electron-dominated reaction pathway for the as-prepared catalyst that was very similar to those induced by Pt/C. The MFC results showed that a maximum power density of ∼642 mW m-2 was obtained using the as-prepared catalyst, which is comparable to that obtained using expensive Pt catalyst. The prepared nitrogen- and boron-co-doped carbon nanoparticles might be an alternative cathode catalyst for MFC applications if large-scale applications and price are considered.

  16. Exploratory fuel-cell research: I. Direct-hydrocarbon polymer-electrolyte fuel cell. II. Mathematical modeling of fuel-cell cathodes

    SciTech Connect

    Perry, M.L.; McLarnon, F.R.; Newman, J.S.; Cairns, E.J.

    1996-12-01

    A strong need exists today for more efficient energy-conversion systems. Our reliance on limited fuel resources, such as petroleum for the majority of our energy needs makes it imperative that we utilize these resources as efficiently as possible. Higher-efficiency energy conversion also means less pollution, since less fuel is consumed and less exhaust created for the same energy output. Additionally, for many industrialized nations, such as the United States which must rely on petroleum imports, it is also imperative from a national-security standpoint to reduce the consumption of these precious resources. A substantial reduction of U.S. oil imports would result in a significant reduction of our trade deficit, as well as costly military spending to protect overseas petroleum resources. Therefore, energy-conversion devices which may utilize alternative fuels are also in strong demand. This paper describes research on fuel cells for transportation.

  17. Modeling of hybrid vehicle fuel economy and fuel engine efficiency

    NASA Astrophysics Data System (ADS)

    Wu, Wei

    "Near-CV" (i.e., near-conventional vehicle) hybrid vehicles, with an internal combustion engine, and a supplementary storage with low-weight, low-energy but high-power capacity, are analyzed. This design avoids the shortcoming of the "near-EV" and the "dual-mode" hybrid vehicles that need a large energy storage system (in terms of energy capacity and weight). The small storage is used to optimize engine energy management and can provide power when needed. The energy advantage of the "near-CV" design is to reduce reliance on the engine at low power, to enable regenerative braking, and to provide good performance with a small engine. The fuel consumption of internal combustion engines, which might be applied to hybrid vehicles, is analyzed by building simple analytical models that reflect the engines' energy loss characteristics. Both diesel and gasoline engines are modeled. The simple analytical models describe engine fuel consumption at any speed and load point by describing the engine's indicated efficiency and friction. The engine's indicated efficiency and heat loss are described in terms of several easy-to-obtain engine parameters, e.g., compression ratio, displacement, bore and stroke. Engine friction is described in terms of parameters obtained by fitting available fuel measurements on several diesel and spark-ignition engines. The engine models developed are shown to conform closely to experimental fuel consumption and motored friction data. A model of the energy use of "near-CV" hybrid vehicles with different storage mechanism is created, based on simple algebraic description of the components. With powertrain downsizing and hybridization, a "near-CV" hybrid vehicle can obtain a factor of approximately two in overall fuel efficiency (mpg) improvement, without considering reductions in the vehicle load.

  18. Structure of the catalytic sites in Fe/N/C-catalysts for O2-reduction in PEM fuel cells

    PubMed Central

    Kramm, Ulrike I.; Herranz, Juan; Larouche, Nicholas; Arruda, Thomas M.; Lefèvre, Michel; Jaouen, Frédéric; Bogdanoff, Peter; Fiechter, Sebastian; Abs-Wurmbach, Irmgard; Mukerjee, Sanjeev; Dodelet, Jean-Pol

    2012-01-01

    Fe-based catalytic sites for the reduction of oxygen in acidic medium have been identified by 57Fe Mössbauer spectroscopy of Fe/N/C catalysts containing 0.03 to 1.55 wt% Fe, which were prepared by impregnation of iron acetate on carbon black followed by heat-treatment in NH3 at 950°C. Four different Fe-species were detected at all iron concentrations: three doublets assigned to molecular FeN4-like sites with their ferrous ion in low (D1), medium (D2) or high spin state (D3), and two other doublets assigned to a single Fe-species (D4 and D5) consisting of surface oxidized nitride nanoparticles (FexN, with x≤2.1). A fifth Fe-species appears only in those catalysts with Fe-contents ≥ 0.27 wt%. It is characterized by a very broad singlet, which has been assigned to incomplete FeN4-like sites that quickly dissolve in contact with an acid. Among the five Fe-species identified in these catalysts, only D1 and D3 display catalytic activity for the oxygen reduction reaction (ORR) in the acid medium, with D3 featuring a composite structure with a protonated neighbour basic nitrogen and being by far the most active species, with an estimated turn over frequency for the ORR of 11.4 e− site−1 s−1 at 0.8V vs RHE. Moreover, all D1 sites and between 1/2 to 2/3 of the D3 sites are acid-resistant. A scheme for the mechanism of site formation upon heat-treatment is also proposed. This identification of the ORR-active sites in these catalysts is of crucial importance to design strategies to improve the catalytic activity and stability of these materials. PMID:22824866

  19. Caffeine consumption.

    PubMed

    Barone, J J; Roberts, H R

    1996-01-01

    Scientific literature cites a wide range of values for caffeine content in food products. The authors suggest the following standard values for the United States: coffee (5 oz) 85 mg for ground roasted coffee, 60 mg for instant and 3 mg for decaffeinated; tea (5 oz): 30 mg for leaf/bag and 20 mg for instant; colas: 18 mg/6 oz serving; cocoa/hot chocolate: 4 mg/5 oz; chocolate milk: 4 mg/6 oz; chocolate candy: 1.5-6.0 mg/oz. Some products from the United Kingdom and Denmark have higher caffeine content. Caffeine consumption survey data are limited. Based on product usage and available consumption data, the authors suggest a mean daily caffeine intake for US consumers of 4 mg/kg. Among children younger than 18 years of age who are consumers of caffeine-containing foods, the mean daily caffeine intake is about 1 mg/kg. Both adults and children in Denmark and UK have higher levels of caffeine intake. PMID:8603790

  20. Deoxyribonucleic acid directed metallization of platinum nanoparticles on graphite nanofibers as a durable oxygen reduction catalyst for polymer electrolyte fuel cells

    NASA Astrophysics Data System (ADS)

    Peera, S. Gouse; Sahu, A. K.; Arunchander, A.; Nath, Krishna; Bhat, S. D.

    2015-11-01

    Effective surface functionalization to the hydrophobic graphite nanofibers (GNF) is performed with the biomolecule, namely deoxy-ribo-nucleic-acid (DNA) via π-π interactions. Pt nanoparticles are impregnated on GNF-DNA composite by ethylene glycol reduction method (Pt/GNF-DNA) and its effect on electro catalytic activity for oxygen reduction reaction (ORR) is systemically studied. Excellent dispersion of Pt nanoparticles over GNF-DNA surfaces with no evidence on particle aggregation is a remarkable achievement in this study. This result in higher electro chemical surface area of the catalyst, enhanced ORR behavior with significant enhancement in mass activity. The catalyst is validated in H2-O2 polymer electrolyte fuel cell (PEFC) and a peak power density of 675 mW cm-2 is achieved at a load current density of 1320 mA cm-2 with a minimal catalyst loading of 0.1 mg cm-2 at a cell temperature of 70 °C and 2 bar absolute pressure. Repeated potential cycling up to 10000 cycles in acidic media is also performed for this catalyst and found excellent stability with only 60 mV drop in the ORR half wave potential. The superior behavior of Pt/GNF-DNA catalyst is credited to the robust fibrous structure of GNF and its effective surface functionalization process via π-π interaction.

  1. Low-cost adsorbent derived and in situ nitrogen/iron co-doped carbon as efficient oxygen reduction catalyst in microbial fuel cells.

    PubMed

    Cao, Chun; Wei, Liling; Su, Min; Wang, Gang; Shen, Jianquan

    2016-08-01

    A novel low-cost adsorbent derived and in situ nitrogen/iron co-doped carbon (N/Fe-C) with three-dimensional porous structure is employed as efficient oxygen reduction catalyst in microbial fuel cells (MFCs). The electrochemical active area is significantly improved to 617.19m(2)g(-1) in N/Fe-C by Fe-doping. And N/Fe-C (4.21at.% N, 0.11at.% Fe) exhibits excellent electrocatalytic activity with the oxygen reduction potential of -0.07V (vs. Ag/AgCl) which is comparable to commercial Pt/C. In MFCs tests, the maximum power density and output voltage with N/Fe-C are enhanced to 745mWm(-2) and 562mV (external resistance 1kΩ), which are 11% and 0.72% higher than Pt/C (0.5mgPtcm(-2)), respectively. Besides, the long-term stability of N/Fe-C retains better for more than one week. Moreover, the charge transfer resistance (Rct) values are recorded by the impedance measurements, and the low Rct of N/Fe-C is also result in better catalytic activity. PMID:27155262

  2. Drag Reduction Tests on Supersonic Transport Design

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Langley researchers recently completed supersonic tests in the Unitary Plan Wind Tunnel on a nonlinear design for a supersonic transport. Although the drag reduction measured during the tests was not as great as that predicted using computational methods, significant drag reductions were achieved. Future tests will be conducted at a higher Reynolds number, which will be more representative of flight conditions. These tests will be used to identify a supersonic transport configuration that provides maximum drag reduction. Reducing drag decreases operating cost by improving fuel consumption and lowering aircraft weight. As a result, this research has the potential to help make a future high-speed civil transport (HSCT) an affordable means of travel for the flying public.

  3. Nitrogen-doped Co/Co9S8/partly-graphitized carbon as durable catalysts for oxygen reduction in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Li, Rui; Dai, Ying; Chen, Baibing; Zou, Jinlong; Jiang, BaoJiang; Fu, Honggang

    2016-03-01

    Durability of catalysts for oxygen reduction reaction (ORR) is the key factor for governing the performance of microbial fuel cells (MFCs). The cobalt (Co) chelated polyaniline (PANI) is used as the nitrogen and carbon sources to prepare the N-doped Co/Co9S8/partly-graphitized carbon (Co/Co9S8/NPGC) catalysts. Structure-activity correlations for Co/Co9S8/NPGC are explored by tuning the heating temperature (600-1000 °C) to investigate how the active components (Co/Co9S8) and N-doped functionalities (N-species) influence the ORR activity. As temperature increases, the gradual crystallization of Co originating from the reduction of Co9S8 is conducted to form the Co/Co9S8 heterojunction. MFCs with Co/Co9S8/NPGC (800 °C) cathode obtain the highest power density (1156 mW m-2) and the lowest charge transfer resistance (11.1 Ω) after 75 d running, which are better than commercial Pt/C (10 wt.%). Although the sole Co9S8 plays a limited role in ORR, the resulting Co/Co9S8 is found to be indispensable to achieve high activity and durability in MFCs cathodes. The dominant ORR pathways of Co/Co9S8/NPGC (800 and 900 °C) are the four-electron O2 reduction, which are attributed to the co-existence of pyridinic N, graphitic N and Co-Nx species. These new N-doped metal sulfide/PGC composites show promise for applications in MFCs.

  4. Combustion characteristics of a turbocharged DI compression ignition engine fueled with petroleum diesel fuels and biodiesel.

    PubMed

    Canakci, Mustafa

    2007-04-01

    In this study, the combustion characteristics and emissions of two different petroleum diesel fuels (No. 1 and No. 2) and biodiesel from soybean oil were compared. The tests were performed at steady state conditions in a four-cylinder turbocharged DI diesel engine at full load at 1400-rpm engine speed. The experimental results compared with No. 2 diesel fuel showed that biodiesel provided significant reductions in PM, CO, and unburned HC, the NO(x) increased by 11.2%. Biodiesel had a 13.8% increase in brake-specific fuel consumption due to its lower heating value. However, using No. 1 diesel fuel gave better emission results, NO(x) and brake-specific fuel consumption reduced by 16.1% and 1.2%, respectively. The values of the principal combustion characteristics of the biodiesel were obtained between two petroleum diesel fuels. The results indicated that biodiesel may be blended with No. 1 diesel fuel to be used without any modification on the engine. PMID:16822672

  5. Reductions in emissions of carbonaceous particulate matter and polycyclic aromatic hydrocarbons from combustion of biomass pellets in comparison with raw fuel burning.

    PubMed

    Shen, Guofeng; Tao, Shu; Wei, Siye; Zhang, Yanyan; Wang, Rong; Wang, Bin; Li, Wei; Shen, Huizhong; Huang, Ye; Chen, Yuanchen; Chen, Han; Yang, Yifeng; Wang, Wei; Wei, Wen; Wang, Xilong; Liu, Wenxing; Wang, Xuejun; Masse Simonich, Staci L y

    2012-06-01

    Biomass pellets are emerging as a cleaner alternative to traditional biomass fuels. The potential benefits of using biomass pellets include improving energy utilization efficiency and reducing emissions of air pollutants. To assess the environmental, climate, and health significance of replacing traditional fuels with biomass pellets, it is critical to measure the emission factors (EFs) of various pollutants from pellet burning. However, only a few field measurements have been conducted on the emissions of carbon monoxide (CO), particulate matter (PM), and polycyclic aromatic hydrocarbons (PAHs) from the combustion of pellets. In this study, pine wood and corn straw pellets were burned in a pellet burner (2.6 kW), and the EFs of CO, organic carbon, elemental carbon, PM, and PAHs (EF(CO), EF(OC), EF(EC), EF(PM), and EF(PAH)) were determined. The average EF(CO), EF(OC), EF(EC), and EF(PM) were 1520 ± 1170, 8.68 ± 11.4, 11.2 ± 8.7, and 188 ± 87 mg/MJ for corn straw pellets and 266 ± 137, 5.74 ± 7.17, 2.02 ± 1.57, and 71.0 ± 54.0 mg/MJ for pine wood pellets, respectively. Total carbonaceous carbon constituted 8 to 14% of the PM mass emitted. The measured values of EF(PAH) for the two pellets were 1.02 ± 0.64 and 0.506 ± 0.360 mg/MJ, respectively. The secondary side air supply in the pellet burner did not change the EFs of most pollutants significantly (p > 0.05). The only exceptions were EF(OC) and EF(PM) for pine wood pellets because of reduced combustion temperatures with the increased air supply. In comparison with EFs for the raw pine wood and corn straw, EF(CO), EF(OC), EF(EC), and EF(PM) for pellets were significantly lower than those for raw fuels (p < 0.05). However, the differences in EF(PAH) were not significant (p > 0.05). Based on the measured EFs and thermal efficiencies, it was estimated that 95, 98, 98, 88, and 71% reductions in the total emissions of CO, OC, EC, PM, and PAHs could be achieved by replacing the raw biomass fuels combusted in

  6. Reductions in Emissions of Carbonaceous Particulate Matter and Polycyclic Aromatic Hydrocarbons from Combustion of Biomass Pellets in Comparisonwith Raw Fuel Burning

    PubMed Central

    SHEN, Guofeng; TAO, Shu; WEI, Siye; ZHANG, Yanyan; WANG, Rong; WANG, Bin; LI, Wei; SHEN, Huizhong; HUANG, Ye; CHEN, Yuanchen; CHEN, Han; YANG, Yifeng; WANG, Wei; WEI, Wen; WANG, Xilong; LIU, Wenxing; WANG, Xuejun; SIMONICH, Staci L. Massey

    2012-01-01

    Biomass pellets are emerging as a cleaner alternative to traditional biomass fuels. The potential benefits of using biomass pellets include improving energy utilization efficiency and reducing emissions of air pollutants. To assess the environmental, climate, and health significance of replacing traditional fuels with biomass pellets, it is critical to measure the emission factors (EFs) of various pollutants from pellet burning. However, only a few field measurements have been conducted on the emissions of carbon monoxide (CO), particulate matter (PM), and polycyclic aromatic hydrocarbons (PAHs) from the combustion of pellets. In this study, pine wood and corn straw pellets were burned in a pellet burner (2.6 kW) and the EFs of CO, organic carbon, elemental carbon, PM, and PAHs (EFCO, EFOC, EFEC, EFPM, and EFPAH) were determined. The average EFCO, EFOC, EFEC, and EFPM were 1520±1170, 8.68±11.4, 11.2±8.7, and 188±87 mg/MJ for corn straw pellets, and 266±137, 5.74±7.17, 2.02±1.57, and 71.0±54.0 mg/MJ for pine wood pellets, respectively. Total carbonaceous carbon constituted 8 to 14% of the PM mass emitted. The measured values of EFPAH for the two pellets were 1.02±0.64 and 0.506±0.360 mg/MJ, respectively. The secondary side air supply in the pellet burner did not change the EFs of most pollutants significantly (p > 0.05). The only exceptions were EFOC and EFPM for pine wood pellets because of reduced combustion temperatures with the increased air supply. In comparison with EFs for the raw pine wood and corn straw, EFCO, EFOC, EFEC, and EFPM for pellets were significantly lower than those for raw fuels (p < 0.05). However, the differences in EFPAH were not significant (p > 0.05). Based on the measured EFs and thermal efficiencies, it was estimated that 95, 98, 98, 88, and 71% reductions in the total emissions of CO, OC, EC, PM, and PAHs could be achieved by replacing the raw biomass fuels combusted in traditional cooking stoves with pellets burned in modern

  7. Alternative Fuels Data Center

    SciTech Connect

    2013-06-01

    Fact sheet describes the Alternative Fuels Data Center, which provides information, data, and tools to help fleets and other transportation decision makers find ways to reduce petroleum consumption through the use of alternative and renewable fuels, advanced vehicles, and other fuel-saving measures.

  8. Consumption: Challenge to sustainable development

    SciTech Connect

    Myers, N.

    1997-04-04

    This editorial about sustainable development points to consumption as one of the four interlinked global problems including population, environment, and development, and the least tractable of the four. Consumption patterns and expectations are deeply entrenched in most cultures, and hard to change, though change will come whether by design or defaults. Among the topics commented on are artificially priced fossil fuels, toxic pollutants, use of nonrenewable resources, etc. Also discussed are policy options and the role of science. A response is included. 21 refs.

  9. Heterogeneous Electrocatalyst of Palladium-Cobalt-Phosphorus on Carbon Support for Oxygen Reduction Reaction in High Temperature Proton Exchange Membrane Fuel Cells.

    PubMed

    You, Dae Jong; Pak, Chanho; Jin, Seon-Ah; Lee, Kang Hee; Kwon, Kyungjung; Choi, Kyoung Hwan; Heo, Pil Won; Jang, Hongchul; Kim, Jun Young; Kim, Ji Man

    2016-05-01

    Palladium-cobalt-phosphorus (PdCoP) catalysts supported on carbon (Ketjen Black) were investigated as a cathode catalyst for oxygen reduction reaction (ORR) in high temperature proton exchange membrane fuel cells (HT-PEMFCs). The PdCoP catalyst was synthesized via a modified polyol process in teflon-sealed reactor by microwave-heating. From X-ray diffraction and transmission electron microscopic analysis, the PdCoP catalyst exhibits a face-centered cubic structure, similar to palladium (Pd), which is attributed to form a good solid solution of Co atoms and P atoms in the Pd lattice. The PdCoP nanoparticles with average diameter of 2.3 nm were uniformly distributed on the carbon support. The electrochemical surface area (ECSA) and ORR activity of PdP, PdCo and PdCoP catalysts were measured using a rotating disk electrode technique with cyclic voltammetry and the linear sweep method. The PdCoP catalysts showed the highest performances for ECSA and ORR, which might be attributed both to formation of small nanoparticle by phosphorus atom and to change in lattice constant of Pd by cobalt atom. Furthermore, The HT-PEMFCs single cell performance employing PdCoP catalyst exhibited an enhanced cell performance compared to a single cell using the PdP and PdCo catalysts. This result indicates the importance of electric and geometric control of Pd alloy nanoparticles that can improve the catalytic activity. This synergistic combination of Co and P with Pd could provide the direction of development of non-Pt catalyst for fuel cell system. PMID:27483757

  10. A global emission inventory of carbonaceous aerosol from historic records of fossil fuel and biofuel consumption for the period 1860-1997

    NASA Astrophysics Data System (ADS)

    Junker, C.; Liousse, C.

    2008-03-01

    Country by country emission inventories for carbonaceous aerosol for the period 1860 to 1997 have been constructed on the basis of historic fuel production, use and trade data sets published by the United Nation's Statistical Division UNSTAT (1997), Etemad et al. (1991) and Mitchell (1992, 1993, 1995). The inventories use emission factors variable over time, which have been determined according to changes in technological development. The results indicate that the industrialisation period since 1860 was accompanied by a steady increase in black carbon (BC) and primary organic carbon (POC) emissions up to 1910. The calculations show a moderate decrease of carbonaceous aerosol emissions between 1920 and 1930, followed by an increase up to 1990, the year when emissions began to decrease again. Changes in BC and POC emissions prior to the year 1950 are essentially driven by the USA, Germany and the UK. The USSR, China and India become substantial contributors to carbonaceous aerosol emissions after 1950. Emission maps have been generated with a 1°×1° resolution based on the relative population density in each country. They will provide a helpful tool for assessing the effect of carbonaceous aerosol emissions on observed climate changes of the past.

  11. A global emission inventory of carbonaceous aerosol from historic records of fossil fuel and biofuel consumption for the period 1860-1997

    NASA Astrophysics Data System (ADS)

    Junker, C.; Liousse, C.

    2006-06-01

    Country by country emission inventories for carbonaceous aerosol for the period 1860 to 1997 have been constructed on the basis of historic fuel production, use and trade data sets published by the United Nation's Statistical Division UNSTAT (1997), Etemad et al. (1991) and Mitchell (1992, 1993, 1995). The inventories use emission factors variable over time, which have been determined according to changes in technological development. The results indicate that the industrialisation period since 1860 was accompanied by a steady increase in black carbon (BC) and organic carbon (OC) emissions up to 1910. The calculations show a moderate decrease of carbonaceous aerosol emissions between 1920 and 1930, followed by an increase up to 1990, the year when emissions began to decrease again. Changes in BC and OC emissions prior to the year 1950 are essentially driven by the USA, Germany and the UK. The USSR, China and India become substantial contributors to carbonaceous aerosol emissions after 1950. Emission maps have been generated with a 1°×1° resolution based on the relative population density in each country. They will provide a helpful tool for assessing the effect of carbonaceous aerosol emissions on observed climate changes of the past.

  12. [Research on carbon reduction potential of electric vehicles for low-carbon transportation and its influencing factors].

    PubMed

    Shi, Xiao-Qing; Li, Xiao-Nuo; Yang, Jian-Xin

    2013-01-01

    Transportation is the key industry of urban energy consumption and carbon emissions. The transformation of conventional gasoline vehicles to new energy vehicles is an important initiative to realize the goal of developing low-carbon city through energy saving and emissions reduction, while electric vehicles (EV) will play an important role in this transition due to their advantage in energy saving and lower carbon emissions. After reviewing the existing researches on energy saving and emissions reduction of electric vehicles, this paper analyzed the factors affecting carbon emissions reduction. Combining with electric vehicles promotion program in Beijing, the paper analyzed carbon emissions and reduction potential of electric vehicles in six scenarios using the optimized energy consumption related carbon emissions model from the perspective of fuel life cycle. The scenarios included power energy structure, fuel type (energy consumption per 100 km), car type (CO2 emission factor of fuel), urban traffic conditions (speed), coal-power technologies and battery type (weight, energy efficiency). The results showed that the optimized model was able to estimate carbon emissions caused by fuel consumption more reasonably; electric vehicles had an obvious restrictive carbon reduction potential with the fluctuation of 57%-81.2% in the analysis of six influencing factors, while power energy structure and coal-power technologies play decisive roles in life-cycle carbon emissions of electric vehicles with the reduction potential of 78.1% and 81.2%, respectively. Finally, some optimized measures were proposed to reduce transport energy consumption and carbon emissions during electric vehicles promotion including improving energy structure and coal technology, popularizing energy saving technologies and electric vehicles, accelerating the battery R&D and so on. The research provides scientific basis and methods for the policy development for the transition of new energy vehicles

  13. Assessment for advanced fuel cycle options in CANDU

    SciTech Connect

    Morreale, A.C.; Luxat, J.C.; Friedlander, Y.

    2013-07-01

    The possible options for advanced fuel cycles in CANDU reactors including actinide burning options and thorium cycles were explored and are feasible options to increase the efficiency of uranium utilization and help close the fuel cycle. The actinide burning TRUMOX approach uses a mixed oxide fuel of reprocessed transuranic actinides from PWR spent fuel blended with natural uranium in the CANDU-900 reactor. This system reduced actinide content by 35% and decreased natural uranium consumption by 24% over a PWR once through cycle. The thorium cycles evaluated used two CANDU-900 units, a generator and a burner unit along with a driver fuel feedstock. The driver fuels included plutonium reprocessed from PWR, from CANDU and low enriched uranium (LEU). All three cycles were effective options and reduced natural uranium consumption over a PWR once through cycle. The LEU driven system saw the largest reduction with a 94% savings while the plutonium driven cycles achieved 75% savings for PWR and 87% for CANDU. The high neutron economy, online fuelling and flexible compact fuel make the CANDU system an ideal reactor platform for many advanced fuel cycles.

  14. Preliminary test results of a flight management algorithm for fuel conservative descents in a time based metered traffic environment. [flight tests of an algorithm to minimize fuel consumption of aircraft based on flight time

    NASA Technical Reports Server (NTRS)

    Knox, C. E.; Cannon, D. G.

    1979-01-01

    A flight management algorithm designed to improve the accuracy of delivering the airplane fuel efficiently to a metering fix at a time designated by air traffic control is discussed. The algorithm provides a 3-D path with time control (4-D) for a test B 737 airplane to make an idle thrust, clean configured descent to arrive at the metering fix at a predetermined time, altitude, and airspeed. The descent path is calculated for a constant Mach/airspeed schedule from linear approximations of airplane performance with considerations given for gross weight, wind, and nonstandard pressure and temperature effects. The flight management descent algorithms and the results of the flight tests are discussed.

  15. Materials Approach to Fuel Efficient Tires

    SciTech Connect

    Votruba-Drzal, Peter; Kornish, Brian

    2015-06-30

    The objective of this project was to design, develop, and demonstrate fuel efficient and safety regulation compliant tire filler and barrier coating technologies that will improve overall fuel efficiency by at least 2%. The program developed and validated two complementary approaches to improving fuel efficiency through tire improvements. The first technology was a modified silica-based product that is 15% lower in cost and/or enables a 10% improvement in tread wear while maintaining the already demonstrated minimum of 2% improvement in average fuel efficiency. The second technology was a barrier coating with reduced oxygen transmission rate compared to the state-of-the-art halobutyl rubber inner liners that will provide extended placarded tire pressure retention at significantly reduced material usage. A lower-permeance, thinner inner liner coating which retains tire pressure was expected to deliver the additional 2% reduction in fleet fuel consumption. From the 2006 Transportation Research Board Report1, a 10 percent reduction in rolling resistance can reduce consumer fuel expenditures by 1 to 2 percent for typical vehicles. This savings is equivalent to 6 to 12 gallons per year. A 1 psi drop in inflation pressure increases the tire's rolling resistance by about 1.4 percent.

  16. [Carbon balance analysis of corn fuel ethanol life cycle].

    PubMed

    Zhang, Zhi-shan; Yuan, Xi-gang

    2006-04-01

    The quantity of greenhouse gas emissions (net carbon emissions) of corn-based fuel ethanol, which is known as an alternative for fossil fuel is an important criteria for evaluating its sustainability. The methodology of carbon balance analysis for fuel ethanol from corn was developed based on principles of life cycle analysis. For the production state of fuel ethanol from summer corn in China, carbon budgets in overall life cycle of the ethanol were evaluated and its main influence factors were identified. It presents that corn-based fuel ethanol has no obvious reduction of carbon emissions than gasoline, and potential improvement in carbon emission of the life cycle of corn ethanol could be achieved by reducing the nitrogen fertilizer and irrigation electricity used in the corn farming and energy consumption in the ethanol conversion process. PMID:16767974

  17. Motor vehicle fuel economy, the forgotten HC control stragegy. [Hydrocarbon (HC)

    SciTech Connect

    Deluchi, M.; Wang, Quanlu; Greene, D.L.

    1992-06-01

    Emissions of hydrocarbons from motor vehicles are recognized as major contributors to ozone pollution in urban areas. Petroleum-based motor fuels contain volatile organic compounds (VOC) which, together with oxides of nitrogen, promote the formation of ozone in the troposphere via complex photochemical reactions. VOC emissions from the tailpipe and evaporation from the fuel and engine systems of highway vehicles are believed to account for about 40% of total VOC emissions in any region. But motor fuels also generate emissions throughout the fuel cycle, from crude oil production to refining, storage, transportation, and handling, that can make significant contributions to the total inventory of VOC emissions. Many of these sources of emissions are directly related to the quantity of fuel produced and handled throughout the fuel cycle. It is, therefore, reasonable to expect that a reduction in total fuel throughput might result in a reduction of VOC emissions. In particular, reducing vehicle fuel consumption by increasing vehicle fuel economy should reduce total fuel throughput, thereby cutting total emissions of VOCS. In this report we identify the sources of VOC emissions throughout the motor fuel cycle, quantify them to the extent possible, and describe their dependence on automobile and light truck fuel economy.

  18. Space Shuttle Main Engine structural analysis and data reduction/evaluation. Volume 7: High pressure fuel turbo-pump third stage impeller analysis

    NASA Technical Reports Server (NTRS)

    Pool, Kirby V.

    1989-01-01

    This volume summarizes the analysis used to assess the structural life of the Space Shuttle Main Engine (SSME) High Pressure Fuel Turbo-Pump (HPFTP) Third Stage Impeller. This analysis was performed in three phases, all using the DIAL finite element code. The first phase was a static stress analysis to determine the mean (non-varying) stress and static margin of safety for the part. The loads involved were steady state pressure and centrifugal force due to spinning. The second phase of the analysis was a modal survey to determine the vibrational modes and natural frequencies of the impeller. The third phase was a dynamic response analysis to determine the alternating component of the stress due to time varying pressure impulses at the outlet (diffuser) side of the impeller. The results of the three phases of the analysis show that the Third Stage Impeller operates very near the upper limits of its capability at full power level (FPL) loading. The static loading alone creates stresses in some areas of the shroud which exceed the yield point of the material. Additional cyclic loading due to the dynamic force could lead to a significant reduction in the life of this part. The cyclic stresses determined in the dynamic response phase of this study are based on an assumption regarding the magnitude of the forcing function.

  19. A review of the stability and durability of non-precious metal catalysts for the oxygen reduction reaction in proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Banham, Dustin; Ye, Siyu; Pei, Katie; Ozaki, Jun-ichi; Kishimoto, Takeaki; Imashiro, Yasuo

    2015-07-01

    A major hurdle to the widespread commercialization of proton exchange membrane fuel cells (PEMFCs) is the high loading of noble metal (Pt/Pt-alloy) catalyst at the cathode, which is necessary to facilitate the inherently sluggish oxygen reduction reaction (ORR). To eliminate the use of Pt/Pt-alloy catalysts at the cathode of PEMFCs and thus significantly reduce the cost, extensive research on non-precious metal catalysts (NPMCs) has been carried out over the past decade. Major advances in improving the ORR activity of NPMCs, particularly Fe- and Co-based NPMCs, have elevated these materials to a level at which they can start to be considered as potential alternatives to Pt/Pt-alloy catalysts. Unfortunately, the stability (performance loss following galvanostatic experiments) of these materials is currently unacceptably low and the durability (performance loss following voltage cycling) remains uncertain. The three primary mechanisms of instability are: (a) Leaching of the metal site, (b) Oxidative attack by H2O2, and (c) Protonation followed by possible anion adsorption of the active site. While (a) has largely been solved, further work is required to understand and prevent losses from (b) and/or (c). Thus, this review is focused on historical progress in (and possible future strategies for) improving the stability/durability of NPMCs.

  20. Carbon nanotubes/heteroatom-doped carbon core-sheath nanostructures as highly active, metal-free oxygen reduction electrocatalysts for alkaline fuel cells.

    PubMed

    Sa, Young Jin; Park, Chiyoung; Jeong, Hu Young; Park, Seok-Hee; Lee, Zonghoon; Kim, Kyoung Taek; Park, Gu-Gon; Joo, Sang Hoon

    2014-04-14

    A facile, scalable route to new nanocomposites that are based on carbon nanotubes/heteroatom-doped carbon (CNT/HDC) core-sheath nanostructures is reported. These nanostructures were prepared by the adsorption of heteroatom-containing ionic liquids on the walls of CNTs, followed by carbonization. The design of the CNT/HDC composite allows for combining the electrical conductivity of the CNTs with the catalytic activity of the heteroatom-containing HDC sheath layers. The CNT/HDC nanostructures are highly active electrocatalysts for the oxygen reduction reaction and displayed one of the best performances among heteroatom-doped nanocarbon catalysts in terms of half-wave potential and kinetic current density. The four-electron selectivity and the exchange current density of the CNT/HDC nanostructures are comparable with those of a Pt/C catalyst, and the CNT/HDC composites were superior to Pt/C in terms of long-term durability and poison tolerance. Furthermore, an alkaline fuel cell that employs a CNT/HDC nanostructure as the cathode catalyst shows very high current and power densities, which sheds light on the practical applicability of these new nanocomposites. PMID:24554521

  1. Efficacy of a solution-based approach for making sodalite waste forms for an oxide reduction salt utilized in the reprocessing of used uranium oxide fuel

    SciTech Connect

    Riley, Brian J.; Pierce, David A.; Frank, Steven M.; Matyáš, Josef; Burns, Carolyne A.

    2015-04-01

    This paper describes the various approaches attempted to make solution-derived sodalite with a LiCl-Li2O oxide reduction salt used to dissolve used uranium oxide fuel so the uranium can be recovered and recycled. The approaches include modified sol-gel and solutionbased synthesis processes. As-made products were mixed with 5 and 10 mass% of a Na2O-B2O3- SiO2 glass binder and these, along with product without a binder, were heated using either a cold-press-and-sinter method or hot uniaxial pressing. The results demonstrate the limitation of sodalite yield due to the fast intermediate reactions between Na+ and Cl- to form halite in solution and Li2O and SiO2 to form lithium silicates (e.g., Li2SiO3 or Li2Si2O5) in the calcined and sintered pellets. The results show that pellets can be made with high sodalite fractions in the crystalline product (~92 mass%) and low porosities using a solution-based approach and this LiCl-Li2O salt but that the incorporation of Li into the sodalite is low.

  2. Efficacy of a solution-based approach for making sodalite waste forms for an oxide reduction salt utilized in the reprocessing of used uranium oxide fuel

    DOE PAGESBeta

    Riley, Brian J.; Pierce, David A.; Frank, Steven M.; Matyáš, Josef; Burns, Carolyne A.

    2015-04-01

    This paper describes the various approaches attempted to make solution-derived sodalite with a LiCl-Li2O oxide reduction salt used to dissolve used uranium oxide fuel so the uranium can be recovered and recycled. The approaches include modified sol-gel and solutionbased synthesis processes. As-made products were mixed with 5 and 10 mass% of a Na2O-B2O3- SiO2 glass binder and these, along with product without a binder, were heated using either a cold-press-and-sinter method or hot uniaxial pressing. The results demonstrate the limitation of sodalite yield due to the fast intermediate reactions between Na+ and Cl- to form halite in solution and Li2Omore » and SiO2 to form lithium silicates (e.g., Li2SiO3 or Li2Si2O5) in the calcined and sintered pellets. The results show that pellets can be made with high sodalite fractions in the crystalline product (~92 mass%) and low porosities using a solution-based approach and this LiCl-Li2O salt but that the incorporation of Li into the sodalite is low.« less

  3. High Performance and Cost-Effective Direct Methanol Fuel Cells: Fe-N-C Methanol-Tolerant Oxygen Reduction Reaction Catalysts.

    PubMed

    Sebastián, David; Serov, Alexey; Artyushkova, Kateryna; Gordon, Jonathan; Atanassov, Plamen; Aricò, Antonino S; Baglio, Vincenzo

    2016-08-01

    Direct methanol fuel cells (DMFCs) offer great advantages for the supply of power with high efficiency and large energy density. The search for a cost-effective, active, stable and methanol-tolerant catalyst for the oxygen reduction reaction (ORR) is still a great challenge. In this work, platinum group metal-free (PGM-free) catalysts based on Fe-N-C are investigated in acidic medium. Post-treatment of the catalyst improves the ORR activity compared with previously published PGM-free formulations and shows an excellent tolerance to the presence of methanol. The feasibility for application in DMFC under a wide range of operating conditions is demonstrated, with a maximum power density of approximately 50 mW cm(-2) and a negligible methanol crossover effect on the performance. A review of the most recent PGM-free cathode formulations for DMFC indicates that this formulation leads to the highest performance at a low membrane-electrode assembly (MEA) cost. Moreover, a 100 h durability test in DMFC shows suitable applicability, with a similar performance-time behavior compared to common MEAs based on Pt cathodes. PMID:27376964

  4. 15N solid-state nuclear magnetic resonance study of pyrolyzed metal-polyaniline cathode catalysts for oxygen reduction in fuel cells

    NASA Astrophysics Data System (ADS)

    Kuroki, Shigeki; Hosaka, Yo; Yamauchi, Chiharu; Nagata, Shinsuke; Sonoda, Mayu

    2015-09-01

    The oxygen reduction reaction (ORR) activity of pyrolyzed metal-free and metal (Mn, Fe, Co, Ni and Cu)-containing polyaniline (PANI) in polymer electrolyte fuel cell (PEFC) was studied. The metal-free PANI800 shows quite poor ORR catalytic activity, whilst the metal-containing PANIMe800 display a better ORR activity. The 15N CP/MAS NMR spectra of PANINi800 and PANICu800 show one weak peak at 118 ppm and there is no peak observed in PANIFe800, against that of PANI800, PANIMn800, PANICo800 and PANINi800 show two peaks at 273 and 118 ppm assigned to the pyridinic and pyridinium nitrogens. It is because of the paramagnetic effect of metal ions. The 15N spin-echo NMR spectra of PANIMe800 with fast recycle delay show the peaks at 140 and 270 ppm assigned to the graphitic and pyridinic nitrogens, against that of PANI800 shows no peak. The spectra of PANIMn800, PANICo800, PANINi800 and PANICu600 also contain a very broaden peak at 430 ppm assigned to the nitrogen with Fermi-contact effect from metal ions. The spectra of PANIFe800 show some spinning side bands and the average Fe3+-15N distance can be calculated. The some amount of iron ion are relieved and average Fe3+-15N distance increase after acid washing and the ORR activity decreases.

  5. Efficacy of a Solution-Based Approach for Making Sodalite Waste Forms for an Oxide Reduction Salt Utilized in the Reprocessing of Used Uranium Oxide Fuel

    SciTech Connect

    Riley, Brian J.; Pierce, David A.; Frank, Steven M.; Matyas, Josef; Burns, Carolyn A.

    2015-04-01

    This paper describes various approaches for making sodalite with a LiCl-Li2O oxide reduction salt used to recover uranium from used oxide fuel. The approaches include sol-gel and solution-based synthesis processes. As-made products were mixed with 5 and 10 mass% of a Na2O-B2O3-SiO2 glass binder and these, along with product without a binder, were heated using either a cold-press-and-sinter method or hot uniaxial pressing. The results demonstrate the limitation of sodalite yield due to the fast intermediate reactions between Na+ and Cl- to form halite in solution and Li2O and SiO2 to form lithium silicates (e.g., Li2SiO3 or Li2Si2O5) in the calcined and sintered pellets. The results show that pellets can be made with high sodalite fractions (~92 mass%) and low porosities using a solution-based approach and this LiCl-Li2O salt.

  6. Gram-level synthesis of core-shell structured catalysts for the oxygen reduction reaction in proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Luo, Mingchuan; Wei, Lingli; Wang, Fanghui; Han, Kefei; Zhu, Hong

    2014-12-01

    Over the past decade, Pt based core-shell structured alloys have been studied extensively as oxygen reduction reaction (ORR) catalysts for proton exchange membrane fuel cells (PEMFCs) because of their distinctive electrochemical performance and low Pt loading. In this paper, a facile route based on microwave-assisted polyol method and chemical dealloying process is proposed to synthesize carbon supported core-shell structured nanoparticles (NPs) in gram-level for ORR electrocatalysis in PEMFCs. The obtained samples are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and X-ray photoelectron spectroscopy (XPS). These physical characterization indicate that the final synthesized NPs are highly dispersed on the carbon support, and in a core-shell structure with CuPt alloy as the core and Pt as the shell. Electrochemical measurements, conducted by cyclic voltammetry (CV) and rotating disk electrode (RDE) tests, show the core-shell structured catalyst exhibit a 3× increase in mass activity and a 2× increase in specific activity over the commercial Pt/C catalyst, respectively. These results demonstrate that this route can be a reliable way to synthesize low-Pt catalyst in large-scale for PEMFCs.

  7. Mesoporous Pt-Co oxygen reduction reaction (ORR) catalysts for low temperature proton exchange membrane fuel cell synthesized by alternating sputtering

    NASA Astrophysics Data System (ADS)

    Sievers, Gustav; Mueller, Steffen; Quade, Antje; Steffen, Florian; Jakubith, Sven; Kruth, Angela; Brueser, Volker

    2014-12-01

    Mesoporous catalysts with enhanced oxygen reduction reaction (ORR) activity for PEM fuel cells are synthesized by alternating sputtering of Pt and Co onto gas diffusion layers with microporous layers. Co is acting as a template for synthesis of a porous Pt nanostructure. For such proposed Pt-Co catalysts the kinetic current in the ORR was found to be increased by a factor of up to 16 and the mass specific current in PEM single cells by a factor of up to 7. Co was found to be deposited at the grain boundary of the Pt layer and dissolves under acidic conditions resulting in a mesoporous Pt catalyst which is advantageous for gas diffusion catalysts. Microstructural and compositional parameters were optimised in order to obtain a high kinetic current and lower onset potential for the ORR. The most favourable Co layer thickness was determined to be 2 nm. The optimal Pt-Co catalyst can be synthesized by continuously varying the Pt layer thickness. The highest Pt mass activity was found at a layer thickness of 30.5 nm. Catalysts were characterised by SEM, EDX, electrochemical half cell and PEM single cell tests.

  8. Microwave-Assisted Synthesis of Reduced Graphene Oxide/SnO2 Nanocomposite for Oxygen Reduction Reaction in Microbial Fuel Cells.

    PubMed

    Garino, Nadia; Sacco, Adriano; Castellino, Micaela; Muñoz-Tabares, José Alejandro; Chiodoni, Angelica; Agostino, Valeria; Margaria, Valentina; Gerosa, Matteo; Massaglia, Giulia; Quaglio, Marzia

    2016-02-24

    We report on an easy, fast, eco-friendly, and reliable method for the synthesis of reduced graphene oxide/SnO2 nanocomposite as cathode material for application in microbial fuel cells (MFCs). The material was prepared starting from graphene oxide that has been reduced to graphene during the hydrothermal synthesis of the nanocomposite, carried out in a microwave system. Structural and morphological characterizations evidenced the formation of nanocomposite sheets, with SnO2 crystals of few nanometers integrated in the graphene matrix. Physico-chemical analysis revealed the formation of SnO2 nanoparticles, as well as the functionalization of the graphene by the presence of nitrogen atoms. Electrochemical characterizations put in evidence the ability of such composite to exploit a cocatalysis mechanism for the oxygen reduction reaction, provided by the presence of both SnO2 and nitrogen. In addition, the novel composite catalyst was successfully employed as cathode in seawater-based MFCs, giving electrical performances comparable to those of reference devices employing Pt as catalyst. PMID:26812440

  9. Efficacy of a solution-based approach for making sodalite waste forms for an oxide reduction salt utilized in the reprocessing of used uranium oxide fuel

    NASA Astrophysics Data System (ADS)

    Riley, Brian J.; Pierce, David A.; Frank, Steven M.; Matyáš, Josef; Burns, Carolyne A.

    2015-04-01

    This paper describes the various approaches evaluated for making solution-derived sodalite with a LiCl-Li2O oxide reduction salt selected to dissolve used uranium oxide fuel so the uranium can be recovered and recycled. The approaches include modified sol-gel and solution-based synthesis processes. As-made products were mixed with 5 and 10 mass% of a Na2O-B2O3-SiO2 glass binder and these, along with product without a binder, were heated using either a cold-press-and-sinter method or hot uniaxial pressing. The results demonstrate the limitation of sodalite yield due to the fast intermediate reactions between Na+ and Cl- to form halite in solution and Li2O and SiO2 to form lithium silicates (e.g., Li2SiO3 or Li2Si2O5) in the calcined and sintered pellets. The results show that pellets can be made with high sodalite fractions in the crystalline product (∼92 mass%) and low porosities using a solution-based approach and this LiCl-Li2O salt but that the incorporation of Li into the sodalite is low.

  10. Can redox sensitive radionuclides be immobilized on the surface of spent nuclear fuel? - A model study on the reduction of Se(IV) aq on Pd-doped UO 2 under H 2 atmosphere

    NASA Astrophysics Data System (ADS)

    Puranen, Anders; Trummer, Martin; Jonsson, Mats

    2009-08-01

    Spent nuclear fuel contains noble metal particles composed of fission products (Pd, Mo, Ru, Tc, Rh and Te, often referred to as ɛ-particles). Studies have shown that these particles play a major role in catalyzing oxidative dissolution as well as H 2 reduction of the oxidized UO 2 fuel matrix, depending on the conditions. Thus it is possible that these particles also could have a major impact on the state of other redox sensitive radionuclides (such as the long lived fission product 79Se) present in spent nuclear fuel. In this study, Pd-doped UO 2 pellets are used to simulate noble metal particles inclusions in spent nuclear fuel and the effect on dissolved selenium in the form of selenite (250 μM selenite) in simulated ground water solution (10 mM NaCl, 10 mM NaHCO 3) at 1 and 10 bar hydrogen pressure. The selenite was found to be reduced to elemental Se, forming colloidal particles. At hydrogen pressures of 10 bar, the rate of selenite reduction was found to be linearly correlated to the fraction of Pd in the UO 2 pellets. No selenium was detected on the surface of the pellets. For the lowest Pd loading (0.1% Pd) the selenite reduction does not appear to proceed to completion indicating that the surface becomes less active.

  11. Household energy consumption and expenditures 1993

    SciTech Connect

    1995-10-05

    This presents information about household end-use consumption of energy and expenditures for that energy. These data were collected in the 1993 Residential Energy Consumption Survey; more than 7,000 households were surveyed for information on their housing units, energy consumption and expenditures, stock of energy-consuming appliances, and energy-related behavior. The information represents all households nationwide (97 million). Key findings: National residential energy consumption was 10.0 quadrillion Btu in 1993, a 9% increase over 1990. Weather has a significant effect on energy consumption. Consumption of electricity for appliances is increasing. Houses that use electricity for space heating have lower overall energy expenditures than households that heat with other fuels. RECS collected data for the 4 most populous states: CA, FL, NY, TX.

  12. Fuel gas from biodigestion

    NASA Technical Reports Server (NTRS)

    Mcdonald, R. C.; Wolverton, B. C.

    1979-01-01

    Biodigestion apparatus produces fuel gas (primarily methane) for domestic consumption, by anaerobic bacterial digestion of organic matter such as aquatic vegetation. System includes 3,786-1 cylindrical container, mechanical agitator, and simple safe gas collector for short term storage.

  13. Cobalt-polypyrrole-carbon black (Co-PPY-CB) Electrocatalysts for the Oxygen Reduction Reaction (ORR) in Fuel Cells: Composition and Kinetic Activity

    SciTech Connect

    D Nguyen-Thanh; A Frenkel; J Wang; S OBrien; D Akins

    2011-12-31

    Electrocatalysts consisting of polypyrrole (PPY) and Co deposited on carbon black (CB) at several compositions were prepared and tested for the oxygen reduction reaction (ORR) in a HClO4 buffer (pH = 1) using a rotating ring-disk electrode (RRDE). It was determined that the most favorable catalyst composition (prior to calcination) had a CB:PPY weight ratio of 2 and a pyrrole:Co (i.e., PY:Co) molar ratio of 4. This catalyst had an onset potential of 0.785 V (vs. RHE) and a mass activity of ca. 1 A/g{sub cata} at the fuel cell relevant voltage of 0.65 V. Furthermore, it was found that the number of electrons exchanged during the ORR with the catalyst was ca. 3.5 and resulted in 28% yield of H{sub 2}O{sub 2} at 0.65 V, which hints to an indirect 4e{sup -} reduction of O{sub 2} to H{sub 2}O, with H{sub 2}O{sub 2} as an intermdiate. From energy dispersive spectroscopy (EDS) and extended X-ray absorption fine structure (EXAFS) analysis, it is proposed that a PY:Co ratio of 4 favors the formation, prior to calcination, in the catalyst precursor of Co-N complexes in which Co is coordinated to 3 or 4 N atoms, resulting in strong Co-N interactions that limit the formation upon calcination of low ORR activity Co nanoparticles. These Co-N complexes give rise upon calcination to CoN{sub x-2} sites in which the coordination of Co could favor the adsorption on them of O{sub 2}, which would make those sites particularly active and selective. At the same mass acitivity of 1 A/g{sub cata}, the voltage yielded by the catalyst was 200 mV lower than that for a state-of-the-art Pt (10 wt.%) catalyst, whoch H{sub 2}O{sub 2} output at 0.85 V was 39% and involves the exchange of 3.2 e{sup -}, overall making our material an attractive substitute to noble metal ORR electrocatalysts.

  14. Fuel economy of hydrogen fuel cell vehicles

    NASA Astrophysics Data System (ADS)

    Ahluwalia, Rajesh K.; Wang, X.; Rousseau, A.; Kumar, R.

    On the basis of on-road energy consumption, fuel economy (FE) of hydrogen fuel cell light-duty vehicles is projected to be 2.5-2.7 times the fuel economy of the conventional gasoline internal combustion engine vehicles (ICEV) on the same platforms. Even with a less efficient but higher power density 0.6 V per cell than the base case 0.7 V per cell at the rated power point, the hydrogen fuel cell vehicles are projected to offer essentially the same fuel economy multiplier. The key to obtaining high fuel economy as measured on standardized urban and highway drive schedules lies in maintaining high efficiency of the fuel cell (FC) system at low loads. To achieve this, besides a high performance fuel cell stack, low parasitic losses in the air management system (i.e., turndown and part load efficiencies of the compressor-expander module) are critical.

  15. Air transportation energy consumption - Yesterday, today, and tomorrow

    NASA Technical Reports Server (NTRS)

    Mascy, A. C.; Williams, L. J.

    1975-01-01

    The energy consumption by aviation is reviewed and projections of its growth are discussed. Forecasts of domestic passenger demand are presented, and the effect of restricted fuel supply and increased fuel prices is considered. The most promising sources for aircraft fuels, their availability and cost, and possible alternative fuels are reviewed. The energy consumption by various air and surface transportation modes is identified and compared on typical portal-to-portal trips. A measure of the indirect energy consumed by ground and air modes is defined. Historical trends in aircraft energy intensities are presented and the potential fuel savings with new technologies are discussed.

  16. Gasoline Ultra Efficient Fuel Vehicle with Advanced Low Temperature Combustion

    SciTech Connect

    Confer, Keith

    2014-09-30

    The objective of this program was to develop, implement and demonstrate fuel consumption reduction technologies which are focused on reduction of friction and parasitic losses and on the improvement of thermal efficiency from in-cylinder combustion. The program was executed in two phases. The conclusion of each phase was marked by an on-vehicle technology demonstration. Phase I concentrated on short term goals to achieve technologies to reduce friction and parasitic losses. The duration of Phase I was approximately two years and the target fuel economy improvement over the baseline was 20% for the Phase I demonstration. Phase II was focused on the development and demonstration of a breakthrough low temperature combustion process called Gasoline Direct- Injection Compression Ignition (GDCI). The duration of Phase II was approximately four years and the targeted fuel economy improvement was 35% over the baseline for the Phase II demonstration vehicle. The targeted tailpipe emissions for this demonstration were Tier 2 Bin 2 emissions standards.

  17. Steam Pressure Reduction, Opportunities, and Issues

    SciTech Connect

    Berry, Jan; Griffin, Mr. Bob; Wright, Anthony L

    2006-01-01

    Steam pressure reduction has the potential to reduce fuel consumption for a minimum capital investment. When the pressure at the boiler is reduced, fuel and steam are saved as a result of changes in the high-pressure side of the steam system from the boiler through the condensate return system. In the boiler plant, losses from combustion, boiler blowdown, radiation, and steam venting from condensate receivers would be reduced by reducing steam pressure. Similarly, in the steam distribution system, losses from radiation, flash steam vented from condensate receivers, and component and steam trap leakage would also be reduced. There are potential problems associated with steam pressure reduction, however. These may include increased boiler carryover, boiler water circulation problems in watertube boilers, increased steam velocity in piping, loss of power in steam turbines, and issues with pressure reducing valves. This paper is based a Steam Technical Brief sponsored by the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy and Enbridge Gas Distribution, Inc. (5). An example illustrates the use of DOE BestPractices Steam System Assessment Tool to model changes in steam, fuel, electricity generation, and makeup water and to estimate resulting economic benefits.

  18. Effects of household dynamics on resource consumption and biodiversity.

    PubMed

    Liu, Jianguo; Daily, Gretchen C; Ehrlich, Paul R; Luck, Gary W

    2003-01-30

    Human population size and growth rate are often considered important drivers of biodiversity loss, whereas household dynamics are usually neglected. Aggregate demographic statistics may mask substantial changes in the size and number of households, and their effects on biodiversity. Household dynamics influence per capita consumption and thus biodiversity through, for example, consumption of wood for fuel, habitat alteration for home building and associated activities, and greenhouse gas emissions. Here we report that growth in household numbers globally, and particularly in countries with biodiversity hotspots (areas rich in endemic species and threatened by human activities), was more rapid than aggregate population growth between 1985 and 2000. Even when population size declined, the number of households increased substantially. Had the average household size (that is, the number of occupants) remained static, there would have been 155 million fewer households in hotspot countries in 2000. Reduction in average household size alone will add a projected 233 million additional households to hotspot countries during the period 2000-15. Rapid increase in household numbers, often manifested as urban sprawl, and resultant higher per capita resource consumption in smaller households pose serious challenges to biodiversity conservation. PMID:12540852

  19. Study on Improving Partial Load by Connecting Geo-thermal Heat Pump System to Fuel Cell Network

    NASA Astrophysics Data System (ADS)

    Obara, Shinya; Kudo, Kazuhiko

    Hydrogen piping, the electric power line, and exhaust heat recovery piping of the distributed fuel cells are connected with network, and operational planning is carried out. Reduction of the efficiency in partial load is improved by operation of the geo-thermal heat pump linked to the fuel cell network. The energy demand pattern of the individual houses in Sapporo was introduced. And the analysis method aiming at minimization of the fuel rate by the genetic algorithm was described. The fuel cell network system of an analysis example assumed connecting the fuel cell co-generation of five houses. When geo-thermal heat pump was introduced into fuel cell network system stated in this paper, fuel consumption was reduced 6% rather than the conventional method

  20. Mass impacts on fuel economies of conventional vs. hybrid electric vehicles.

    SciTech Connect

    An, F.; Santini, D. J.; Energy Systems

    2004-01-01

    The strong correlation between vehicle weight and fuel economy for conventional vehicles (CVs) is considered common knowledge, and the relationship of mass reduction to fuel consumption reduction for conventional vehicles (CVs) is often cited without separating effects of powertrain vs. vehicle body (glider), nor on the ground of equivalent vehicle performance level. This paper challenges the assumption that this relationship is easily summarized. Further, for hybrid electric vehicles (HEVs) the relationship between mass, performance and fuel consumption is not the same as for CVs, and vary with hybrid types. For fully functioning (all wheel regeneration) hybrid vehicles, where battery pack and motor(s) have enough power and energy storage, a very large fraction of kinetic energy is recovered and engine idling is effectively eliminated. This paper assesses two important impacts of shifting from conventional to hybrid vehicles in terms of the mass vs. fuel economy relationship - (1) significant improvements in fuel economy with little or no change in mass, and (2) once a switch to hybrid powertrains has been made, the effectiveness of mass reduction in improving fuel economy will be diminished relative to conventional vehicles. In this paper, we discuss vehicle tractive load breakdowns and impacts of hybridization on vehicle efficiency, discuss capture of kinetic energy by conversion to electrical energy via regenerative braking, assess benefits of shutting off the engine when the vehicle does not require power, and investigate energy losses associated with vehicle mass.