Solar Energy: Its Technologies and Applications

DOE R&D Accomplishments Database

Auh, P. C.

1978-06-01

Solar heat, as a potential source of clean energy, is available to all of us. Extensive R and D efforts are being made to effectively utilize this renewable energy source. A variety of different technologies for utilizing solar energy have been proven to be technically feasible. Here, some of the most promising technologies and their applications are briefly described. These are: Solar Heating and Cooling of Buildings (SHACOB), Solar Thermal Energy Conversion (STC), Wind Energy Conversion (WECS), Bioconversion to Fuels (BCF), Ocean Thermal Energy Conversion (OTEC), and Photovoltaic Electric Power Systems (PEPS). Special emphasis is placed on the discussion of the SHACOB technologies, since the technologies are being expeditiously developed for the near commercialization.

Solar electric and thermal conversion system in close proximity to the consumer. [solar panels on house roofs

NASA Technical Reports Server (NTRS)

Boeer, K. W.

1975-01-01

Solar cells may be used to convert sunlight directly into electrical energy and into lowgrade heat to be used for large-scale terrestrial solar-energy conversion. Both forms of energy can be utilized if such cells are deployed in close proximity to the consumer (rooftop). Cadmium-sulfide/copper-sulfide (CdS/Cu2S) solar cells are an example of cells which may be produced inexpensively enough to become economically attractive. Cell parameters relevant for combined solar conversion are presented. Critical issues, such as production yield, life expectancy, and stability of performance, are discussed. Systems-design parameters related to operating temperatures are analyzed. First results obtained on Solar One, the experimental house of the University of Delaware, are given. Economic aspects are discussed. Different modes of operation are discussed in respect to the power utility and consumer incentives.

Solar power satellite system definition study. Volume 1, phase 2: Executive summary

NASA Technical Reports Server (NTRS)

1979-01-01

A review of solar energy conversion and utilization is presented. The solar power satellite system is then described. Overall system definition and integration is discussed. Principal reference system study accomplishments and conclusions are presented.

Method and system for controlling a gasification or partial oxidation process

DOEpatents

Rozelle, Peter L; Der, Victor K

2015-02-10

A method and system for controlling a fuel gasification system includes optimizing a conversion of solid components in the fuel to gaseous fuel components, controlling the flux of solids entrained in the product gas through equipment downstream of the gasifier, and maximizing the overall efficiencies of processes utilizing gasification. A combination of models, when utilized together, can be integrated with existing plant control systems and operating procedures and employed to develop new control systems and operating procedures. Such an approach is further applicable to gasification systems that utilize both dry feed and slurry feed.

Laparoscopic colon resection trends in utilization and rate of conversion to open procedure: a national database review of academic medical centers.

PubMed

Simorov, Anton; Shaligram, Abhijit; Shostrom, Valerie; Boilesen, Eugene; Thompson, Jon; Oleynikov, Dmitry

2012-09-01

This study aims to examine trends of utilization and rates of conversion to open procedure for patients undergoing laparoscopic colon resections (LCR). This study is a national database review of academic medical centers and a retrospective analysis utilizing the University HealthSystem Consortium administrative database-an alliance of more than 300 academic and affiliate hospitals. A total of 85,712 patients underwent colon resections between October 2008 and December 2011. LCR was attempted in 36,228 patients (42.2%), with 5751 patients (15.8%) requiring conversion to an open procedure. There was a trend toward increasing utilization of LCR from 37.5% in 2008 to 44.1% in 2011. Attempted laparoscopic transverse colectomy had the highest rate of conversion (20.8%), followed by left (20.7%), right (15.6%), and sigmoid (14.3%) colon resections. The rate of utilization was highest in the Mid-Atlantic region (50.5%) and in medium- to large-sized hospitals (47.0%-49.0%).Multivariate logistic regression has shown that increasing age [odds ratio (OR) = 4.8, 95% confidence interval (CI) = 3.6-6.4], male sex (OR = 1.2, 95% CI = 1.1-1.3), open as compared with laparoscopic approach (OR = 2.6, 95%, CI = 2.3-3.1), and greater severity of illness category (OR = 27.1, 95% CI = 23.0-31.9) were all associated with increased mortality and morbidity and prolonged length of hospital stay. There is a trend of increasing utilization of LCR, with acceptable conversion rates, across hospitals in the United States over the recent years. When feasible, attempted LCR had better outcomes than open colectomy in the immediate perioperative period.

Improving Donor Conversion Rates at a Level One Trauma Center: Impact of Best Practice Guidelines

PubMed Central

Gibbons, Bobby L; Bershad, Vanessa L

2016-01-01

Background Organ availability is a consistently limiting factor in transplant surgery. A primary driver of this limitation is donor conversion rate, which is defined as the percentage of eligible donors for whom procurement is actually performed. An alternative way to increase organ availability is through improved utilization of organs from donors after cardiac death (DCD). Recently, a concerted, multidisciplinary effort has been made within our system to improve conversion rates and DCD utilization, thus increasing organ availability. Study design Retrospective analysis of a prospectively collected database from TransLife, our local organ procurement organization (OPO), as well as the Orlando Regional Medical Center (ORMC) trauma registry, from 2009-2012 (up to 2013 for DCD). During which time, this organization implemented best practice guidelines to improve conversions and DCD utilization. We analyzed yearly conversion rates, DCD donations and population demographics before and after implementation of these policies. Results During the study period, donor conversion rates significantly improved from 58% in 2009 to 82% percent in 2012 hospital-wide (P<0.05); and from 50% in 2009 to 81% in 2012 among trauma patients alone (P<0.05). In addition, total organs transplanted increased from 13 to 31 organs (P<0.05) after implementation of best practice guidelines. No significant differences in trauma population demographics were noted during the study period. Conclusions Based on our experience, the establishment of best practice policies for referral of potential donors, coupled with programs to educate hospital staff on the existence and importance of these policies, leads to significant improvement in donor conversion rates and increased utilization of DCD donors. PMID:28018761

System and method for single-phase, single-stage grid-interactive inverter

DOEpatents

Liu, Liming; Li, Hui

2015-09-01

The present invention provides for the integration of distributed renewable energy sources/storages utilizing a cascaded DC-AC inverter, thereby eliminating the need for a DC-DC converter. The ability to segment the energy sources and energy storages improves the maintenance capability and system reliability of the distributed generation system, as well as achieve wide range reactive power compensation. In the absence of a DC-DC converter, single stage energy conversion can be achieved to enhance energy conversion efficiency.

OAST space power technology program

NASA Technical Reports Server (NTRS)

Mullin, J. P.

1978-01-01

The current research and technology (R and T) base program is first described, then special attention is directed toward outlining a new system technology specifically oriented toward providing the utility power plant technology base for semi-permanent earth orbital facilities expected to be needed in the middle to late 1980's. The R and T program involves five areas of research: (1) photovoltaic energy conversion; (2) chemical energy conversion and storage; (3) thermal-to-electric conversion; (4) environment interactions; and (5) power systems management and distribution. The general objectives and planned direction of efforts in each of these areas is summarized.

48 CFR 917.7200 - Scope of subpart.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., conversion, and utilization of non-nuclear energy resources. [61 FR 41706, Aug. 9, 1996, as amended at 74 FR... Section 917.7200 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACTING METHODS AND... application of all potentially beneficial nonnuclear energy sources and utilization technologies. (b) This...

48 CFR 917.7200 - Scope of subpart.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., conversion, and utilization of non-nuclear energy resources. [61 FR 41706, Aug. 9, 1996, as amended at 74 FR... Section 917.7200 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACTING METHODS AND... application of all potentially beneficial nonnuclear energy sources and utilization technologies. (b) This...

48 CFR 917.7200 - Scope of subpart.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., conversion, and utilization of non-nuclear energy resources. [61 FR 41706, Aug. 9, 1996, as amended at 74 FR... Section 917.7200 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACTING METHODS AND... application of all potentially beneficial nonnuclear energy sources and utilization technologies. (b) This...

48 CFR 917.7200 - Scope of subpart.

Code of Federal Regulations, 2010 CFR

2010-10-01

... application of all potentially beneficial non nuclear energy sources and utilization technologies. (b) This..., conversion, and utilization of non-nuclear energy resources. [61 FR 41706, Aug. 9, 1996, as amended at 74 FR... Section 917.7200 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACTING METHODS AND...

48 CFR 917.7200 - Scope of subpart.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., conversion, and utilization of non-nuclear energy resources. [61 FR 41706, Aug. 9, 1996, as amended at 74 FR... Section 917.7200 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACTING METHODS AND... application of all potentially beneficial nonnuclear energy sources and utilization technologies. (b) This...

Carbon dioxide conversion over carbon-based nanocatalysts.

PubMed

Khavarian, Mehrnoush; Chai, Siang-Piao; Mohamed, Abdul Rahman

2013-07-01

The utilization of carbon dioxide for the production of valuable chemicals via catalysts is one of the efficient ways to mitigate the greenhouse gases in the atmosphere. It is known that the carbon dioxide conversion and product yields are still low even if the reaction is operated at high pressure and temperature. The carbon dioxide utilization and conversion provides many challenges in exploring new concepts and opportunities for development of unique catalysts for the purpose of activating the carbon dioxide molecules. In this paper, the role of carbon-based nanocatalysts in the hydrogenation of carbon dioxide and direct synthesis of dimethyl carbonate from carbon dioxide and methanol are reviewed. The current catalytic results obtained with different carbon-based nanocatalysts systems are presented and how these materials contribute to the carbon dioxide conversion is explained. In addition, different strategies and preparation methods of nanometallic catalysts on various carbon supports are described to optimize the dispersion of metal nanoparticles and catalytic activity.

Method to monitor HC-SCR catalyst NOx reduction performance for lean exhaust applications

DOEpatents

Viola, Michael B [Macomb Township, MI; Schmieg, Steven J [Troy, MI; Sloane, Thompson M [Oxford, MI; Hilden, David L [Shelby Township, MI; Mulawa, Patricia A [Clinton Township, MI; Lee, Jong H [Rochester Hills, MI; Cheng, Shi-Wai S [Troy, MI

2012-05-29

A method for initiating a regeneration mode in selective catalytic reduction device utilizing hydrocarbons as a reductant includes monitoring a temperature within the aftertreatment system, monitoring a fuel dosing rate to the selective catalytic reduction device, monitoring an initial conversion efficiency, selecting a determined equation to estimate changes in a conversion efficiency of the selective catalytic reduction device based upon the monitored temperature and the monitored fuel dosing rate, estimating changes in the conversion efficiency based upon the determined equation and the initial conversion efficiency, and initiating a regeneration mode for the selective catalytic reduction device based upon the estimated changes in conversion efficiency.

Photovoltaic and thermal energy conversion for solar powered satellites

NASA Technical Reports Server (NTRS)

Von Tiesenhausen, G. F.

1976-01-01

A summary is provided concerning the most important aspects of present investigations related to a use of solar power satellites (SPS) as a future source of terrestrial energy. General SPS characteristics are briefly considered, early work is reviewed, and a description of current investigations is presented. System options presently under study include a photovoltaic array, a thermionic system, and a closed Brayton cycle. Attention is given to system reference options, basic building blocks, questions of system analysis and engineering, photovoltaic conversion, and the utility interface. It is concluded that an SPS may be cost effective compared to terrestrial systems by 1995.

Low cost composite materials for wind energy conversion systems

NASA Technical Reports Server (NTRS)

Weingart, O.

1980-01-01

A winding process utilizing a low-cost E-glass fabric called transverse-filament tape for low-cost production of wind turbine generators (WTG) is described. The process can be carried out continuously at high speed to produce large one-piece parts with tapered wall thicknesses on a tapered mandrel. It is being used to manufacture blades for the NASA/DOE 200-ft-diameter MOD-1 WTG and Rockwell/DOE 40-kW small wind energy conversion system (SWECS).

A comparison of Stirling engines for use with a 25 kW dish-electric conversion system

NASA Technical Reports Server (NTRS)

Shaltens, Richard K.

1987-01-01

Two designs for an advanced Stirling conversion system (ASCS) are described. The objective of the ASCS is to generate about 25 kW of electric power to an electric utility grid at an engine/alternator target cost of $300.00/kW at the manufacturing rate of 10,000 unit/yr. Both designs contain a free-piston Stirling engine (FPSE), a heat transport system, solar receiver, a means to generate electric power, the necessary auxiliaries, and a control system. The major differences between the two concepts are: one uses a 25 kWe single-piston FPSE which incorporates a linear alternator to directly convert the energy to electricity on the utility grid; and in the second design, electrical power is generated indirectly using a hydraulic output to a ground based hydraulic motor coupled to a rotating alternator. Diagrams of the two designs are presented.

Status of the advanced Stirling conversion system project for 25 kW dish Stirling applications

NASA Technical Reports Server (NTRS)

Shaltens, Richard K.; Schreiber, Jeffrey G.

1991-01-01

Technology development for Stirling convertors directed toward a dynamic power source for space applications is discussed. Space power requirements include high reliability with very long life, low vibration, and high system efficiency. The free-piston Stirling engine has the potential for future high power space conversion systems, either nuclear or solar powered. Although these applications appear to be quite different, their requirements complement each other. The advanced Stirling conversion system (ASCS) project at NASA Lewis Research Center is described. Each system design features a solar receiver/liquid metal heat transport system and a free-piston Stirling convertor with a means to provide nominally 25 kW of electric power to utility grid while meeting the US Department of Energy (DOE) performance and long term cost goals. The design is compared with other ASCS designs.

System Design for a Nuclear Electric Spacecraft Utilizing Out-of-core Thermionic Conversion

NASA Technical Reports Server (NTRS)

Estabrook, W. C.; Phillips, W. M.; Hsieh, T.

1976-01-01

Basic guidelines are presented for a nuclear space power system which utilizes heat pipes to transport thermal power from a fast nuclear reactor to an out of core thermionic converter array. Design parameters are discussed for the nuclear reactor, heat pipes, thermionic converters, shields (neutron and gamma), waste heat rejection systems, and the electrical bus bar-cable system required to transport the high current/low voltage power to the processing equipment. Dimensions are compatible with shuttle payload bay constraints.

Nuclear power for space based systems

NASA Astrophysics Data System (ADS)

Livingston, J. M.; Ivanenok, Joseph F., III

1991-09-01

A 100 kWe closed Brayton cycle power conversion system utilizing a recuperator coupled to a NERVA derivative reactor for a lunar power plant is presented. Power plant mass versus recuperator effectiveness, compressor inlet temperature, and turbine pressure ratio are described.

Electrochemically enhanced microbial CO conversion to volatile fatty acids using neutral red as an electron mediator.

PubMed

Im, Chae Ho; Kim, Changman; Song, Young Eun; Oh, Sang-Eun; Jeon, Byong-Hun; Kim, Jung Rae

2018-01-01

Conversion of C1 gas feedstock, including carbon monoxide (CO), into useful platform chemicals has attracted considerable interest in industrial biotechnology. Nevertheless, the low conversion yield and/or growth rate of CO-utilizing microbes make it difficult to develop a C1 gas biorefinery process. The Wood-Ljungdahl pathway which utilize CO is a pathway suffered from insufficient electron supply, in which the conversion can be increased further when an additional electron source like carbohydrate or hydrogen is provided. In this study, electrode-based electron transference using a bioelectrochemical system (BES) was examined to compensate for the insufficient reducing equivalent and increase the production of volatile fatty acids. The BES including neutral red (BES-NR), which facilitated electron transfer between bacteria and electrode, was compared with BES without neutral red and open circuit control. The coulombic efficiency based on the current input to the system and the electrons recovered into VFAs, was significantly higher in BES-NR than the control. These results suggest that the carbon electrode provides a platform to regulate the redox balance for improving the bioconversion of CO, and amending the conventional C1 gas fermentation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Solar-energy conversion system provides electrical power and thermal control for life-support systems

NASA Technical Reports Server (NTRS)

Davis, B. K.

1974-01-01

System utilizes Freon cycle and includes boiler turbogenerator with heat exchanger, regenerator and thermal-control heat exchangers, low-pressure and boiler-feed pumps, and condenser. Exchanger may be of interest to engineers and scientists investigating new energy sources.

The effects of aquaculture production noise on the growth, condition factor, feed conversion, and survival of rainbow trout, Oncorhynchus mykiss

USDA-ARS?s Scientific Manuscript database

Intensive aquaculture systems, particularly recirculating systems, utilize equipment such as aerators, air and water pumps, blowers, and filtration systems that inadvertently increase noise levels in fish culture tanks. Sound levels and frequencies measured within intensive aquaculture systems are w...

Review of NASA programs in applying aerospace technology to energy

NASA Technical Reports Server (NTRS)

Schwenk, F. C.

1981-01-01

NASA's role in energy research and development, with the aid of aerospace technology, is reviewed. A brief history, which began in 1974 with studies of solar energy systems on earth, is presented, and the major energy programs, consisting of over 60 different projects, are described, and include solar terrestrial systems, conservation and fossil energy systems, and space utilization systems. Special attention is given to the Satellite Power System and the isolation of nuclear wastes in space. Emerging prospects for NASA programs in energy technology include bioenergy, and ocean thermal energy conversion, coal extraction and conversion technologies, and support to the nuclear industry in power plant systems safety.

Systems biology-guided biodesign of consolidated lignin conversion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Lu; Cheng, Yanbing; Pu, Yunqiao

Lignin is the second most abundant biopolymer on the earth, yet its utilization for fungible products is complicated by its recalcitrant nature and remains a major challenge for sustainable lignocellulosic biorefineries. In this study, we used a systems biology approach to reveal the carbon utilization pattern and lignin degradation mechanisms in a unique lignin-utilizing Pseudomonas putida strain (A514). The mechanistic study further guided the design of three functional modules to enable a consolidated lignin bioconversion route. First, P. putida A514 mobilized a dye peroxidase-based enzymatic system for lignin depolymerization. This system could be enhanced by overexpressing a secreted multifunctional dyemore » peroxidase to promote a two-fold enhancement of cell growth on insoluble kraft lignin. Second, A514 employed a variety of peripheral and central catabolism pathways to metabolize aromatic compounds, which can be optimized by overexpressing key enzymes. Third, the β-oxidation of fatty acid was up-regulated, whereas fatty acid synthesis was down-regulated when A514 was grown on lignin and vanillic acid. Therefore, the functional module for polyhydroxyalkanoate (PHA) production was designed to rechannel β-oxidation products. As a result, PHA content reached 73% per cell dry weight (CDW). Further integrating the three functional modules enhanced the production of PHA from kraft lignin and biorefinery waste. Furthermore, this study elucidated lignin conversion mechanisms in bacteria with potential industrial implications and laid out the concept for engineering a consolidated lignin conversion route.« less

Systems biology-guided biodesign of consolidated lignin conversion

DOE PAGES

Lin, Lu; Cheng, Yanbing; Pu, Yunqiao; ...

2016-07-12

Lignin is the second most abundant biopolymer on the earth, yet its utilization for fungible products is complicated by its recalcitrant nature and remains a major challenge for sustainable lignocellulosic biorefineries. In this study, we used a systems biology approach to reveal the carbon utilization pattern and lignin degradation mechanisms in a unique lignin-utilizing Pseudomonas putida strain (A514). The mechanistic study further guided the design of three functional modules to enable a consolidated lignin bioconversion route. First, P. putida A514 mobilized a dye peroxidase-based enzymatic system for lignin depolymerization. This system could be enhanced by overexpressing a secreted multifunctional dyemore » peroxidase to promote a two-fold enhancement of cell growth on insoluble kraft lignin. Second, A514 employed a variety of peripheral and central catabolism pathways to metabolize aromatic compounds, which can be optimized by overexpressing key enzymes. Third, the β-oxidation of fatty acid was up-regulated, whereas fatty acid synthesis was down-regulated when A514 was grown on lignin and vanillic acid. Therefore, the functional module for polyhydroxyalkanoate (PHA) production was designed to rechannel β-oxidation products. As a result, PHA content reached 73% per cell dry weight (CDW). Further integrating the three functional modules enhanced the production of PHA from kraft lignin and biorefinery waste. Furthermore, this study elucidated lignin conversion mechanisms in bacteria with potential industrial implications and laid out the concept for engineering a consolidated lignin conversion route.« less

Recent progress in solution plasma-synthesized-carbon-supported catalysts for energy conversion systems

NASA Astrophysics Data System (ADS)

Lun Li, Oi; Lee, Hoonseung; Ishizaki, Takahiro

2018-01-01

Carbon-based materials have been widely utilized as the electrode materials in energy conversion and storage technologies, such as fuel cells and metal-air batteries. In these systems, the oxygen reduction reaction is an important step that determines the overall performance. A novel synthesis route, named the solution plasma process, has been recently utilized to synthesize various types of metal-based and heteroatom-doped carbon catalysts. In this review, we summarize cutting-edge technologies involving the synthesis and modeling of carbon-supported catalysts synthesized via solution plasma process, followed by current progress on the electrocatalytic performance of these catalysts. This review provides the fundamental and state-of-the-art performance of solution-plasma-synthesized electrode materials, as well as the remaining scientific and technological challenges for this process.

Sorghums for methane production. Final report, April 1983 to March 1986

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hiler, E.A.; Miller, F.R.; Dominy, R.E.

1986-06-01

The objective of the research is to develop an integrated system for methane production utilizing high-energy sorghum as the feedstock. The report provides specifics of research activities in the sorghums-for-methane production program sponsored by Gas Research Institute and co-funded by Texas Agricultural Experiment Station. Emphasis is placed on third-year results in the report since first- and second-year results are given in earlier reports. Researchers in the program include plant geneticists, sorghum physiologists, chemists, agronomists, ruminant physiologists, agricultural and systems engineers, and agricultural economists. Major research emphasis is on genetic manipulation, physiology and production systems, harvesting, storage, processing and conversion systems,more » inhibitors, and economic and systems analyses. During the third year, increasing emphasis continued on the storage, processing, and conversion aspects of the program because of the critical importance of high efficiency and conversion to the economic implementation of the system.« less

Conservation and Renewable Energy Program: Bibliography, 1988 edition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vaughan, K.H.

The 831 references covering the period 1980 through Feb. 1988, are arranged under the following: analysis and evaluation, building equipment, building thermal envelope systems and materials, community systems and cogeneration, residential conservation service, retrofit, advanced heat engine ceramics, alternative fuels, microemulsion fuels, industrial chemical heat pumps, materials for waste heat utilization, energy conversion and utilization materials, tribology, emergency energy conservation,inventions, electric energy systems, thermal storage, biofuels production, biotechnology, solar technology, geothermal, and continuous chromatography in multicomponent separations. An author index is included.

Performance characteristics of solar-photovoltaic flywheel-storage systems

NASA Astrophysics Data System (ADS)

Jarvinen, P. O.; Brench, B. L.; Rasmussen, N. E.

A solar photovoltaic energy flywheel storage and conversion system for residential applications was tested. Performance and efficiency measurements were conducted on the system, which utilizes low loss magnetic bearings, maximum power point tracking of the photovoltaic array, integrated permanent magnet motor generator, and output power conditioning sections of either the stand alone cycloconverter or utility interactive inverter type. The overall in/out electrical storage efficiency of the flywheel system was measured along with the power transfer efficiencies of the individual components and the system spin down tare losses. The system compares favorably with systems which use batteries and inverters.

Investigation on energy conversion technology using biochemical reaction elements, 2

NASA Astrophysics Data System (ADS)

1994-03-01

For measures taken for resource/energy and environmental issues, a study is made on utilization of microbial biochemical reaction. As a reaction system using chemical energy, cited is production of petroleum substitution substances and food/feed by CO2 fixation using hydrogen energy and hydrogen bacteria. As to photo energy utilization, regarded as promising are CO2 fixation using photo energy and microalgae, and production of hydrogen and useful carbon compound using photosynthetic organisms. As living organism/electric energy interconversion, cited is the culture of chemoautotrophic bacteria which fix CO2 using electric energy. For enhancing its conversion efficiency, it is important to develop a technology of gene manipulation of the bacteria and a system to use functional biochemical elements adaptable to the electrode reaction. With regard to utilization of the microorganism metabolic function, the paper presents emission of soluble nitrogen in the hydrosphere into the atmosphere using denitrifying bacteria, removal of phosphorus, reduction in environmental pollution caused by heavy metal dilute solutions, and recovery as resources, etc.

Lunar electric power systems utilizing the SP-100 reactor coupled to dynamic conversion systems

NASA Technical Reports Server (NTRS)

Harty, Richard B.; Durand, Richard E.

1993-01-01

An integration study was performed by Rocketdyne under contract to NASA-LeRC. The study was concerned with coupling an SP-0100 reactor to either a Brayton or Stirling power conversion system. The application was for a surface power system to supply power requirements to a lunar base. A power level of 550 kWe was selected based on the NASA Space Exploration Initiative 90-day study. Reliability studies were initially performed to determine optimum power conversion redundancy. This study resulted in selecting three operating engines and one stand-by unit. Integration design studies indicated that either the Brayton or Stirling power conversion systems could be integrated with the PS-100 reactor. The Stirling system had an integration advantage because of smaller piping size and fewer components. The Stirling engine, however, is more complex and heavier than the Brayton rotating unit, which tends to off-set the Stirling integration advantage. From a performance consideration, the Brayton had a 9 percent mass advantage, and the Stirling had a 50 percent radiator advantage.

Research and evaluation of biomass resources/conversion/utilization systems. Biomass allocation model. Volume 1: Test and appendices A & B

NASA Astrophysics Data System (ADS)

Stringer, R. P.; Ahn, Y. K.; Chen, H. T.; Helm, R. W.; Nelson, E. T.; Shields, K. J.

1981-08-01

A biomass allocation model was developed to show the most profitable combination of biomass feedstocks, thermochemical conversion processes, and fuel products to serve the seasonal conditions in a regional market. This optimization model provides a tool for quickly calculating which of a large number of potential biomass missions is the most profitable mission. Other components of the system serve as a convenient storage and retrieval mechanism for biomass marketing and thermochemical conversion processing data. The system can be accessed through the use of a computer terminal, or it could be adapted to a microprocessor. A User's Manual for the system is included. Biomass derived fuels included in the data base are the following: medium Btu gas, low Btu gas, substitute natural gas, ammonia, methanol, electricity, gasoline, and fuel oil.

Open-Cycle Gas Turbine/Steam Turbine Combined Cycles with synthetic fuels from coal

NASA Technical Reports Server (NTRS)

Shah, R. P.; Corman, J. C.

1977-01-01

The Open-Cycle Gas Turbine/Steam Turbine Combined Cycle can be an effective energy conversion system for converting coal to electricity. The intermediate step in this energy conversion process is to convert the coal into a fuel acceptable to a gas turbine. This can be accomplished by producing a synthetic gas or liquid, and by removing, in the fuel conversion step, the elements in the fuel that would be harmful to the environment if combusted. In this paper, two open-cycle gas turbine combined systems are evaluated: one employing an integrated low-Btu gasifier, and one utilizing a semi-clean liquid fuel. A consistent technical/economic information base is developed for these two systems, and is compared with a reference steam plant burning coal directly in a conventional furnace.

Conversion and Validation of Distribution System Model from a QSTS-Based Tool to a Real-Time Dynamic Phasor Simulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chamana, Manohar; Prabakar, Kumaraguru; Palmintier, Bryan

A software process is developed to convert distribution network models from a quasi-static time-series tool (OpenDSS) to a real-time dynamic phasor simulator (ePHASORSIM). The description of this process in this paper would be helpful for researchers who intend to perform similar conversions. The converter could be utilized directly by users of real-time simulators who intend to perform software-in-the-loop or hardware-in-the-loop tests on large distribution test feeders for a range of use cases, including testing functions of advanced distribution management systems against a simulated distribution system. In the future, the developers intend to release the conversion tool as open source tomore » enable use by others.« less

Conversion and Validation of Distribution System Model from a QSTS-Based Tool to a Real-Time Dynamic Phasor Simulator: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chamana, Manohar; Prabakar, Kumaraguru; Palmintier, Bryan

A software process is developed to convert distribution network models from a quasi-static time-series tool (OpenDSS) to a real-time dynamic phasor simulator (ePHASORSIM). The description of this process in this paper would be helpful for researchers who intend to perform similar conversions. The converter could be utilized directly by users of real-time simulators who intend to perform software-in-the-loop or hardware-in-the-loop tests on large distribution test feeders for a range of use cases, including testing functions of advanced distribution management systems against a simulated distribution system. In the future, the developers intend to release the conversion tool as open source tomore » enable use by others.« less

A space-based combined thermophotovoltaic electric generator and gas laser solar energy conversion system

NASA Technical Reports Server (NTRS)

Yesil, Oktay

1989-01-01

This paper describes a spaceborne energy conversion system consisting of a thermophotovoltaic electric generator and a gas laser. As a power source for the converson, the system utilizes an intermediate blackbody cavity heated to a temperature of 2000-2400 K by concentrated solar radiation. A double-layer solar cell of GaAs and Si forms a cylindrical surface concentric to this blackbody cavity, receiving the blackbody radiation and converting it into electricity with cell conversion efficiency of 50 percent or more. If the blackbody cavity encloses a laser medium, the blackbody radiation can also be used to simultaneously pump a lasing gas. The feasibility of blackbody optical pumping at 4.3 microns in a CO2-He gas mixture was experimentally demonstrated.

High-speed photonically assisted analog-to-digital conversion using a continuous wave multiwavelength source and phase modulation.

PubMed

Bortnik, Bartosz J; Fetterman, Harold R

2008-10-01

A more simple photonically assisted analog-to-digital conversion system utilizing a cw multiwavelength source and phase modulation instead of a mode-locked laser is presented. The output of the cw multiwavelength source is launched into a dispersive device (such as a single-mode fiber). This fiber creates a pulse train, where the central wavelength of each pulse corresponds to a spectral line of the optical source. The pulses can then be either dispersed again to perform discrete wavelength time stretching or demultiplexed for continuous time analog-to-digital conversion. We experimentally demonstrate the operation of both time stretched and interleaved systems at 38 GHz. The potential of integrating this type of system on a monolithic chip is discussed.

Tunable molten oxide pool assisted plasma-melter vitrification systems

DOEpatents

Titus, Charles H.; Cohn, Daniel R.; Surma, Jeffrey E.

1998-01-01

The present invention provides tunable waste conversion systems and apparatus which have the advantage of highly robust operation and which provide complete or substantially complete conversion of a wide range of waste streams into useful gas and a stable, nonleachable solid product at a single location with greatly reduced air pollution to meet air quality standards. The systems provide the capability for highly efficient conversion of waste into high quality combustible gas and for high efficiency conversion of the gas into electricity by utilizing a high efficiency gas turbine or an internal combustion engine. The solid product can be suitable for various commercial applications. Alternatively, the solid product stream, which is a safe, stable material, may be disposed of without special considerations as hazardous material. In the preferred embodiment, the arc plasma furnace and joule heated melter are formed as a fully integrated unit with a common melt pool having circuit arrangements for the simultaneous independently controllable operation of both the arc plasma and the joule heated portions of the unit without interference with one another. The preferred configuration of this embodiment of the invention utilizes two arc plasma electrodes with an elongated chamber for the molten pool such that the molten pool is capable of providing conducting paths between electrodes. The apparatus may additionally be employed with reduced use or without further use of the gases generated by the conversion process. The apparatus may be employed as a net energy or net electricity producing unit where use of an auxiliary fuel provides the required level of electricity production. Methods and apparatus for converting metals, non-glass forming waste streams and low-ash producing inorganics into a useful gas are also provided. The methods and apparatus for such conversion include the use of a molten oxide pool having predetermined electrical, thermal and physical characteristics capable of maintaining optimal joule heating and glass forming properties during the conversion process.

Pilot testing a digital pet avatar for older adults.

PubMed

Chi, Nai-Ching; Sparks, Olivia; Lin, Shih-Yin; Lazar, Amanda; Thompson, Hilaire J; Demiris, George

Social isolation in older adults is a major public health concern. An embodied conversational agent (ECA) has the potential to enhance older adults' social interaction. However, little is known about older adults' experience with an ECA. In this paper, we conducted a pilot study to examine the perceived acceptance and utility of a tablet-based conversational agent in the form of an avatar (termed "digital pet") for older adults. We performed secondary analysis of data collected from a study that employed the use of a digital pet in ten older adults' homes for three months. Most of the participants enjoyed the companionship, entertainment, reminders, and instant assistance from the digital pet. However, participants identified limited conversational ability and technical issues as system challenges. Privacy, dependence, and cost were major concerns. Future applications should maximize the agent's conversational ability and the system's overall usability. Our results can inform future designs of conversational agents for older adults, which need to include older adults as system co-designers to maximize usability and acceptance. Copyright © 2017 Elsevier Inc. All rights reserved.

Status of wind-energy conversion

NASA Technical Reports Server (NTRS)

Thomas, R. L.; Savino, J. M.

1973-01-01

The utilization of wind energy is technically feasible as evidenced by the many past demonstrations of wind generators. The cost of energy from the wind has been high compared to fossil fuel systems. A sustained development effort is needed to obtain economical systems. The variability of the wind makes it an unreliable source on a short-term basis. However, the effects of this variability can be reduced by storage systems or connecting wind generators to fossil fuel systems, hydroelectric systems, or dispersing them throughout a large grid network. The NSF and NASA-Lewis Research Center have sponsored programs for the utilization of wind energy.

Investigation of self-excited induction generators for wind turbine applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muljadi, E.; Butterfield, C.P.; Sallan, J.

2000-02-28

The use of squirrel-cage induction machines in wind generation is widely accepted as a generator of choice. The squirrel-cage induction machine is simple, reliable, cheap, lightweight, and requires very little maintenance. Generally, the induction generator is connected to the utility at constant frequency. With a constant frequency operation, the induction generator operates at practically constant speed (small range of slip). The wind turbine operates in optimum efficiency only within a small range of wind speed variation. The variable-speed operation allows an increase in energy captured and reduces both the torque peaks in the drive train and the power fluctuations sentmore » to the utility. In variable-speed operation, an induction generator needs an interface to convert the variable frequency output of the generator to the fixed frequency at the utility. This interface can be simplified by using a self-excited generator because a simple diode bridge is required to perform the ac/dc conversion. The subsequent dc/ac conversion can be performed using different techniques. The use of a thyristor bridge is readily available for large power conversion and has a lower cost and higher reliability. The firing angle of the inverter bridge can be controlled to track the optimum power curve of the wind turbine. With only diodes and thyristors used in power conversion, the system can be scaled up to a very high voltage and high power applications. This paper analyzes the operation of such a system applied to a 1/3-hp self-excited induction generator. It includes the simulations and tests performed for the different excitation configurations.« less

The use of information systems to transform utilities and regulatory commissions: The application of geographic information systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wirick, D.W.; Montgomery, G.E.; Wagman, D.C.

1995-09-01

One technology that can assist utilities remain financially viable in competitive markets and help utilities and regulators to better serve the public is information technology. Because geography is an important part of an electric, natural gas, telecommunications, or water utility, computer-based Geographic Information Systems (GIS) and related Automated Mapping/Facilities Management systems are emerging as core technologies for managing an ever-expanding variety of formerly manual or paper-based tasks. This report focuses on GIS as an example of the types of information systems that can be used by utilities and regulatory commissions. Chapter 2 provides general information about information systems and effectsmore » of information on organizations; Chapter 3 explores the conversion of an organization to an information-based one; Chapters 4 and 5 set out GIS as an example of the use of information technologies to transform the operations of utilities and commissions; Chapter 6 describes the use of GIS and other information systems for organizational reengineering efforts; and Chapter 7 examines the regulatory treatment of information systems.« less

Investigation of direct solar-to-microwave energy conversion techniques

NASA Technical Reports Server (NTRS)

Chatterton, N. E.; Mookherji, T. K.; Wunsch, P. K.

1978-01-01

Identification of alternative methods of producing microwave energy from solar radiation for purposes of directing power to the Earth from space is investigated. Specifically, methods of conversion of optical radiation into microwave radiation by the most direct means are investigated. Approaches based on demonstrated device functioning and basic phenomenologies are developed. There is no system concept developed, that is competitive with current baseline concepts. The most direct methods of conversion appear to require an initial step of production of coherent laser radiation. Other methods generally require production of electron streams for use in solid-state or cavity-oscillator systems. Further development is suggested to be worthwhile for suggested devices and on concepts utilizing a free-electron stream for the intraspace station power transport mechanism.

Three phase power conversion system for utility interconnected PV applications

NASA Astrophysics Data System (ADS)

Porter, David G.

1999-03-01

Omnion Power Engineering Corporation has developed a new three phase inverter that improves the cost, reliability, and performance of three phase utility interconnected photovoltaic inverters. The inverter uses a new, high manufacturing volume IGBT bridge that has better thermal performance than previous designs. A custom easily manufactured enclosure was designed. Controls were simplified to increase reliability while maintaining important user features.

Energy cogeneration handbook

DOE Office of Scientific and Technical Information (OSTI.GOV)

Polimeros, G.

1981-01-01

Design criteria for central plants that facilitate energy conversion, utilization, and conservation, an evaluation of project alternatives and an examination of systems and their functions to achieve optimum overall design in the generation of heating, cooling, and electricity are presented.

Study of aircraft electrical power systems

NASA Technical Reports Server (NTRS)

1972-01-01

The formulation of a philosophy for devising a reliable, efficient, lightweight, and cost effective electrical power system for advanced, large transport aircraft in the 1980 to 1985 time period is discussed. The determination and recommendation for improvements in subsystems and components are also considered. All aspects of the aircraft electrical power system including generation, conversion, distribution, and utilization equipment were considered. Significant research and technology problem areas associated with the development of future power systems are identified. The design categories involved are: (1) safety-reliability, (2) power type, voltage, frequency, quality, and efficiency, (3) power control, and (4) selection of utilization equipment.

Conversion of LARSYS III.1 to an IBM 370 computer

NASA Technical Reports Server (NTRS)

Williams, G. N.; Leggett, J.; Hascall, G. A.

1975-01-01

A software system for processing multispectral aircraft or satellite data (LARSYS) was designed and written at the Laboratory for Applications of Remote Sensing at Purdue University. This system, being implemented on an IBM 360/67 computer utilizing the Cambridge Monitor System, is of an interactive nature. TAMU LARSYS maintains the essential capabilities of Purdue's LARSYS. The machine configuration for which it has been converted is an IBM-compatible Amdahl 470V/6 computer utilizing the time sharing option of the currently implemented OS/VS2 Operating System. Due to TSO limitations, the NASA-JSC deliverable TAMU LARSYS is comprised of two parts. Part one is a TSO Control Card Checker for LARSYS control cards, and part two is a batch version of LARSYS. Used together, they afford most of the capabilities of the original LARSYS III.1. Additionally, two programs have been written by TAMU to support LARSYS processing. The first is an ERTS-to-MIST conversion program used to convert ERTS data to the LARSYS input form, the MIST tape. The second is a system runtable code which maintains tape/file location information for the MIST data sets.

Cogeneration Technology Alternatives Study (CTAS) Volume 5: Analytical approach and results

NASA Technical Reports Server (NTRS)

1980-01-01

Data and information in the area of advanced energy conversion systems for industrial cogeneration applications in the 1985 to 2000 time period are provided. Six current and thirty-six advanced energy conversion systems were defined and combined with appropriate balance of plant equipment. Twenty-six industrial processes were selected from among the high energy consuming industries to serve as a framework for the study. Each conversion system was analyzed as a cogenerator with each industrial plant. Fuel consumption, costs, and environmental intrusion were evaluated and compared to corresponding traditional values. Various cogeneration strategies were analyzed and both topping and bottoming (using industrial by-product heat) applications were included. The advanced energy conversion technologies indicated reduced fuel consumption, costs, and emissions. Typically fuel energy savings of 10 to 25 percent were predicted compared to traditional on site furnaces and utility electricity. Gas turbines and combined cycles indicated high overall annual cost savings. Steam turbines and gas turbines produced high estimated returns. In some applications, diesels were most efficient. The advanced technologies used coal derived fuels, or coal with advanced fluid bed combustion or on site gasification systems.

Tunable, self-powered integrated arc plasma-melter vitrification system for waste treatment and resource recovery

DOEpatents

Titus, Charles H.; Cohn, Daniel R.; Surma, Jeffrey E.

1998-01-01

The present invention provides a relatively compact self-powered, tunable waste conversion system and apparatus which has the advantage of highly robust operation which provides complete or substantially complete conversion of a wide range of waste streams into useful gas and a stable, nonleachable solid product at a single location with greatly reduced air pollution to meet air quality standards. The system provides the capability for highly efficient conversion of waste into high quality combustible gas and for high efficiency conversion of the gas into electricity by utilizing a high efficiency gas turbine or by an internal combustion engine. The solid product can be suitable for various commercial applications. Alternatively, the solid product stream, which is a safe, stable material, may be disposed of without special considerations as hazardous material. In the preferred embodiment of the invention, the arc plasma furnace and joule heated melter are formed as a fully integrated unit with a common melt pool having circuit arrangements for the simultaneous independently controllable operation of both the arc plasma and the joule heated portions of the unit without interference with one another. The preferred configuration of this embodiment of the invention utilizes two arc plasma electrodes with an elongated chamber for the molten pool such that the molten pool is capable of providing conducting paths between electrodes. The apparatus may additionally be employed with reduced or without further use of the gases generated by the conversion process. The apparatus may be employed as a self-powered or net electricity producing unit where use of an auxiliary fuel provides the required level of electricity production.

ERDA-NASA wind energy project ready to involve users

NASA Technical Reports Server (NTRS)

Thomas, R.; Puthoff, R.; Savino, J.; Johnson, W.

1976-01-01

The NASA contribution to the Wind Energy Project is discussed. NASA is responsible for the following: (1) identification of cost-effective configurations and sizes of wind-conversion systems, (2) the development of technology needed to produce these systems, (3) the design of wind-conversion systems that are compatible with user requirements, particularly utility networks, and (4) technology transfer obtained from the program to stimulate rapid commercial application of wind systems. Various elements of the NASA program are outlined, including industry-built user operation, the evaluation phase, the proposed plan and schedule for site selection and user involvement, supporting research and technology (e.g., energy storage), and component and subsystem technology development.

Continuous production of ethanol from hexoses and pentoses using immobilized mixed cultures of Escherichia coli strains

PubMed Central

Unrean, Pornkamol; Srienc, Friedrich

2010-01-01

We have developed highly efficient ethanologenic E. coli strains that selectively consume pentoses and/or hexoses. Mixed cultures of these strains can be used to selectively adjust the sugar utilization kinetics in ethanol fermentations. Based on the kinetics of sugar utilization, we have designed and implemented an immobilized cell system for the optimized continuous conversion of sugars into ethanol. The results confirm that immobilized mixed cultures support a simultaneous conversion of hexoses and pentoses into ethanol at high yield and at a faster rate than immobilized homogenous cells. Continuous ethanol production has been maintained for several weeks at high productivity with near complete sugar utilization. The control of sugar utilization using immobilized mixed cultures can be adapted to any composition of hexoses and pentoses by adjusting the strain distribution of immobilized cells. The approach, therefore, holds promise for ethanol fermentation from lignocellulosic hydrolysates where the feedstock varies in sugar composition. PMID:20699108

Efficient electrochemical CO2 conversion powered by renewable energy.

PubMed

Kauffman, Douglas R; Thakkar, Jay; Siva, Rajan; Matranga, Christopher; Ohodnicki, Paul R; Zeng, Chenjie; Jin, Rongchao

2015-07-22

The catalytic conversion of CO2 into industrially relevant chemicals is one strategy for mitigating greenhouse gas emissions. Along these lines, electrochemical CO2 conversion technologies are attractive because they can operate with high reaction rates at ambient conditions. However, electrochemical systems require electricity, and CO2 conversion processes must integrate with carbon-free, renewable-energy sources to be viable on larger scales. We utilize Au25 nanoclusters as renewably powered CO2 conversion electrocatalysts with CO2 → CO reaction rates between 400 and 800 L of CO2 per gram of catalytic metal per hour and product selectivities between 80 and 95%. These performance metrics correspond to conversion rates approaching 0.8-1.6 kg of CO2 per gram of catalytic metal per hour. We also present data showing CO2 conversion rates and product selectivity strongly depend on catalyst loading. Optimized systems demonstrate stable operation and reaction turnover numbers (TONs) approaching 6 × 10(6) molCO2 molcatalyst(-1) during a multiday (36 h total hours) CO2 electrolysis experiment containing multiple start/stop cycles. TONs between 1 × 10(6) and 4 × 10(6) molCO2 molcatalyst(-1) were obtained when our system was powered by consumer-grade renewable-energy sources. Daytime photovoltaic-powered CO2 conversion was demonstrated for 12 h and we mimicked low-light or nighttime operation for 24 h with a solar-rechargeable battery. This proof-of-principle study provides some of the initial performance data necessary for assessing the scalability and technical viability of electrochemical CO2 conversion technologies. Specifically, we show the following: (1) all electrochemical CO2 conversion systems will produce a net increase in CO2 emissions if they do not integrate with renewable-energy sources, (2) catalyst loading vs activity trends can be used to tune process rates and product distributions, and (3) state-of-the-art renewable-energy technologies are sufficient to power larger-scale, tonne per day CO2 conversion systems.

The energy crisis and energy from the sun; Proceedings of the Symposium on Solar Energy Utilization, Washington, D.C., April 30, 1974

NASA Technical Reports Server (NTRS)

Thekaekara, M. P.

1974-01-01

Papers on the state of the art and future prospects of solar energy utilization in the United States are included. Research and technologies for heating and cooling of buildings, solar thermal energy conversion, photovoltaic conversion, biomass production and conversion, wind energy conversion and ocean thermal energy conversion are covered. The increasing funding of the National Solar Energy Program is noted. Individual items are announced in this issue.

Distribution Feeder Modeling for Time-Series Simulation of Voltage Management Strategies: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Giraldez Miner, Julieta I; Gotseff, Peter; Nagarajan, Adarsh

This paper presents techniques to create baseline distribution models using a utility feeder from Hawai'ian Electric Company. It describes the software-to-software conversion, steady-state, and time-series validations of a utility feeder model. It also presents a methodology to add secondary low-voltage circuit models to accurately capture the voltage at the customer meter level. This enables preparing models to perform studies that simulate how customer-sited resources integrate into legacy utility distribution system operations.

Thermally driven electrokinetic energy conversion with liquid water microjets

DOE PAGES

Lam, Royce K.; Gamlieli, Zach; Harris, Stephen J.; ...

2015-11-01

One goal of current energy research is to design systems and devices that can efficiently exploit waste heat and utilize solar or geothermal heat energy for electrical power generation. We demonstrate a novel technique exploiting water's large coefficient of thermal expansion, wherein modest thermal gradients produce the requisite high pressure for driving fast-flowing liquid water microjets, which can effect the direct conversion of the kinetic energy into electricity and gaseous hydrogen. Waste heat in thermoelectric generating plants and combustion engines, as well as solar and geothermal energy could be used to drive these systems.

A real time spectrum to dose conversion system

NASA Technical Reports Server (NTRS)

Farmer, B. J.; Johnson, J. H.; Bagwell, R. G.

1972-01-01

A system has been developed which permits the determination of dose in real time or near real time directly from the pulse-height output of a radiation spectrometer. The technique involves the use of the resolution matrix of a spectrometer, the radiation energy-to-dose conversion function, and the geometrical factors, although the order of matrix operations is reversed. The new technique yields a result which is mathematically identical to the standard method while requiring no matrix manipulations or resolution matrix storage in the remote computer. It utilizes only a single function for each type dose required and each geometric factor involved.

Thermally driven electrokinetic energy conversion with liquid water microjets

NASA Astrophysics Data System (ADS)

Lam, Royce K.; Gamlieli, Zach; Harris, Stephen J.; Saykally, Richard J.

2015-11-01

A goal of current energy research is to design systems and devices that can efficiently exploit waste heat and utilize solar or geothermal heat energy for electrical power generation. We demonstrate a novel technique exploiting water's large coefficient of thermal expansion, wherein modest thermal gradients produce the requisite high pressure for driving fast-flowing liquid water microjets, which can effect the direct conversion of the kinetic energy into electricity and gaseous hydrogen. Waste heat in thermoelectric generating plants and combustion engines, as well as solar and geothermal energy could be used to drive these systems.

In situ conversion process utilizing a closed loop heating system

DOEpatents

Sandberg, Chester Ledlie [Palo Alto, CA; Fowler, Thomas David [Houston, TX; Vinegar, Harold J [Bellaire, TX; Schoeber, Willen Jan Antoon Henri

2009-08-18

An in situ conversion system for producing hydrocarbons from a subsurface formation is described. The system includes a plurality of u-shaped wellbores in the formation. Piping is positioned in at least two of the u-shaped wellbores. A fluid circulation system is coupled to the piping. The fluid circulation system is configured to circulate hot heat transfer fluid through at least a portion of the piping to form at least one heated portion of the formation. An electrical power supply is configured to provide electrical current to at least a portion of the piping located below an overburden in the formation to resistively heat at least a portion of the piping. Heat transfers from the piping to the formation.

A synthetic biochemistry platform for cell free production of monoterpenes from glucose

DOE Office of Scientific and Technical Information (OSTI.GOV)

Korman, Tyler P.; Opgenorth, Paul H.; Bowie, James U.

Cell-free systems designed to perform complex chemical conversions of biomass to biofuels or commodity chemicals are emerging as promising alternatives to the metabolic engineering of living cells. We design a system comprises 27 enzymes for the conversion of glucose into monoterpenes that generates both NAD(P)H and ATP in a modified glucose breakdown module and utilizes both cofactors for building terpenes. Different monoterpenes are produced in our system by changing the terpene synthase enzyme. The system is stable for the production of limonene, pinene and sabinene, and can operate continuously for at least 5 days from a single addition of glucose.more » We also obtain conversion yields 495% and titres 415 g l -1. The titres are an order of magnitude over cellular toxicity limits and thus difficult to achieve using cell-based systems. Overall, these results highlight the potential of synthetic biochemistry approaches for producing bio-based chemicals.« less

A synthetic biochemistry platform for cell free production of monoterpenes from glucose

DOE PAGES

Korman, Tyler P.; Opgenorth, Paul H.; Bowie, James U.

2017-05-24

Cell-free systems designed to perform complex chemical conversions of biomass to biofuels or commodity chemicals are emerging as promising alternatives to the metabolic engineering of living cells. We design a system comprises 27 enzymes for the conversion of glucose into monoterpenes that generates both NAD(P)H and ATP in a modified glucose breakdown module and utilizes both cofactors for building terpenes. Different monoterpenes are produced in our system by changing the terpene synthase enzyme. The system is stable for the production of limonene, pinene and sabinene, and can operate continuously for at least 5 days from a single addition of glucose.more » We also obtain conversion yields 495% and titres 415 g l -1. The titres are an order of magnitude over cellular toxicity limits and thus difficult to achieve using cell-based systems. Overall, these results highlight the potential of synthetic biochemistry approaches for producing bio-based chemicals.« less

Solar photovoltaic power systems: an electric utility R & d perspective.

PubMed

Demeo, E A; Taylor, R W

1984-04-20

Solar photovoltaic technology is receiving increasing attention as a prospective source of bulk, electric utility power within the next 10 to 20 years. Successful development will require solar energy conversion efficiencies of about 15 percent for photovoltaic flat-plate modules, or about 25 percent for photovoltaic cells using highly concentrated sunlight. Three different cell technologies have a better than even chance of achieving these target efficiencies with costs and operating lifetimes that would allow significant use by electric utilities. The challenge for the next decade is to push photovoltaic technology to its physical limits while expanding markets and user confidence with currently available systems.

Ultra-low-power conversion and management techniques for thermoelectric energy harvesting applications

NASA Astrophysics Data System (ADS)

Fleming, Jerry W.

2010-04-01

Thermoelectric energy harvesting has increasingly gained acceptance as a potential power source that can be used for numerous commercial and military applications. However, power electronic designers have struggled to incorporate energy harvesting methods into their designs due to the relatively small voltage levels available from many harvesting device technologies. In order to bridge this gap, an ultra-low input voltage power conversion method is needed to convert small amounts of scavenged energy into a usable form of electricity. Such a method would be an enabler for new and improved medical devices, sensor systems, and other portable electronic products. This paper addresses the technical challenges involved in ultra-low-voltage power conversion by providing a solution utilizing novel power conversion techniques and applied technologies. Our solution utilizes intelligent power management techniques to control unknown startup conditions. The load and supply management functionality is also controlled in a deterministic manner. The DC to DC converter input operating voltage is 20mV with a conversion efficiency of 90% or more. The output voltage is stored into a storage device such as an ultra-capacitor or lithium-ion battery for use during brown-out or unfavorable harvesting conditions. Applications requiring modular, low power, extended maintenance cycles, such as wireless instrumentation would significantly benefit from the novel power conversion and harvesting techniques outlined in this paper.

Development of suspended core soft glass fibers for far-detuned parametric conversion

NASA Astrophysics Data System (ADS)

Rampur, Anupamaa; Ciąćka, Piotr; Cimek, Jarosław; Kasztelanic, Rafał; Buczyński, Ryszard; Klimczak, Mariusz

2018-04-01

Light sources utilizing χ (2) parametric conversion combine high brightness with attractive operation wavelengths in the near and mid-infrared. In optical fibers, it is possible to use χ (3) degenerate four-wave mixing in order to obtain signal-to-idler frequency detuning of over 100 THz. We report on a test series of nonlinear soft glass suspended core fibers intended for parametric conversion of 1000-1100 nm signal wavelengths available from an array of mature lasers into the near-to-mid-infrared range of 2700-3500 nm under pumping with an erbium sub-picosecond laser system. The presented discussion includes modelling of the fiber properties, details of their physical development and characterization, and experimental tests of parametric conversion.

Transcriptomic Analysis of Xylan Utilization Systems in Paenibacillus sp

Treesearch

Neha Sawhney; Casey Crooks; Franz St. John; James F. Preston; R. M. Kelly

2014-01-01

Xylans, including methylglucuronoxylans (MeGXn) and methylglucuronoarabinoxylans (MeGAXn), are the predominant polysaccharides in hemicellulose fractions of dicots and monocots available for conversion to biofuels and chemicals. Paenibacillus sp. strain JDR-2 (Pjdr2) efficiently depolymerizes MeGX

Cogeneration Technology Alternatives Study (CTAS). Volume 3: Industrial processes

NASA Technical Reports Server (NTRS)

Palmer, W. B.; Gerlaugh, H. E.; Priestley, R. R.

1980-01-01

Cogenerating electric power and process heat in single energy conversion systems rather than separately in utility plants and in process boilers is examined in terms of cost savings. The use of various advanced energy conversion systems are examined and compared with each other and with current technology systems for their savings in fuel energy, costs, and emissions in individual plants and on a national level. About fifty industrial processes from the target energy consuming sectors were used as a basis for matching a similar number of energy conversion systems that are considered as candidate which can be made available by the 1985 to 2000 time period. The sectors considered included food, textiles, lumber, paper, chemicals, petroleum, glass, and primary metals. The energy conversion systems included steam and gas turbines, diesels, thermionics, stirling, closed cycle and steam injected gas turbines, and fuel cells. Fuels considered were coal, both coal and petroleum based residual and distillate liquid fuels, and low Btu gas obtained through the on site gasification of coal. An attempt was made to use consistent assumptions and a consistent set of ground rules specified by NASA for determining performance and cost. Data and narrative descriptions of the industrial processes are given.

Molecular approaches to third generation photovoltaics: photochemical up-conversion

NASA Astrophysics Data System (ADS)

Cheng, Yuen Yap; Fückel, Burkhard; Roberts, Derrick A.; Khoury, Tony; Clady, Rapha"l. G. C. R.; Tayebjee, Murad J. Y.; Piper, Roland; Ekins-Daukes, N. J.; Crossley, Maxwell J.; Schmidt, Timothy W.

2010-08-01

We have investigated a photochemical up-conversion system comprising a molecular mixture of a palladium porphyrin to harvest light, and a polycyclic aromatic hydrocarbon to emit light. The energy of harvested photons is stored as molecular triplet states which then annihilate to bring about up-converted fluorescence. The limiting efficiency of such triplet-triplet annihilation up-conversion has been believed to be 11% for some time. However, by rigorously investigating the kinetics of delayed fluorescence following pulsed excitation, we demonstrate instantaneous annihilation efficiencies exceeding 40%, and limiting efficiencies for the current system of ~60%. We attribute the high efficiencies obtained to the electronic structure of the emitting molecule, which exhibits an exceptionally high T2 molecular state. We utilize the kinetic data obtained to model an up-converting layer irradiated with broadband sunlight, finding that ~3% efficiencies can be obtained with the current system, with this improving dramatically upon optimization of various parameters.

Wind Energy Conversion System Analysis Model (WECSAM) computer program documentation

NASA Astrophysics Data System (ADS)

Downey, W. T.; Hendrick, P. L.

1982-07-01

Described is a computer-based wind energy conversion system analysis model (WECSAM) developed to predict the technical and economic performance of wind energy conversion systems (WECS). The model is written in CDC FORTRAN V. The version described accesses a data base containing wind resource data, application loads, WECS performance characteristics, utility rates, state taxes, and state subsidies for a six state region (Minnesota, Michigan, Wisconsin, Illinois, Ohio, and Indiana). The model is designed for analysis at the county level. The computer model includes a technical performance module and an economic evaluation module. The modules can be run separately or together. The model can be run for any single user-selected county within the region or looped automatically through all counties within the region. In addition, the model has a restart capability that allows the user to modify any data-base value written to a scratch file prior to the technical or economic evaluation.

RELEASE NOTES FOR MODELS-3 VERSION 4.1 PATCH: SMOKE TOOL AND FILE CONVERTER

EPA Science Inventory

This software patch to the Models-3 system corrects minor errors in the Models-3 framework, provides substantial improvements in the ASCII to I/O API format conversion of the File Converter utility, and new functionalities for the SMOKE Tool. Version 4.1 of the Models-3 system...

Constructing a LabVIEW-Controlled High-Performance Liquid Chromatography (HPLC) System: An Undergraduate Instrumental Methods Exercise

ERIC Educational Resources Information Center

Smith, Eugene T.; Hill, Marc

2011-01-01

In this laboratory exercise, students develop a LabVIEW-controlled high-performance liquid chromatography system utilizing a data acquisition device, two pumps, a detector, and fraction collector. The programming experience involves a variety of methods for interface communication, including serial control, analog-to-digital conversion, and…

A GIS-based Model for Natural Gas Data Conversion

NASA Astrophysics Data System (ADS)

Bitik, E.; Seker, D. Z.; Denli, H. H.

2014-12-01

In Turkey gas utility sector has undergone major changes in terms of increased competition between gas providers, efforts in improving services, and applying new technological solutions. This paper discusses the challenges met by gas companies to switch from long workflows of gas distribution, sales and maintenance into IT driven efficient management of complex information both spatially and non-spatially. The aim of this study is migration of all gas data and information into a GIS environment in order to manage and operate all infrastructure investments with a Utility Management System. All data conversion model for migration was designed and tested during the study. A flowchart is formed to transfer the old data layers to the new structure based on geodatabase.

Conceptual design of closed Brayton cycle for coal-fired power generation

NASA Technical Reports Server (NTRS)

Shah, R. P.; Corman, J. C.

1977-01-01

The objectives to be realized in developing a closed cycle gas turbine are (1) to exploit high temperature gas turbine technology while maintaining a working fluid which is free from combustion gas contamination, (2) to achieve compact turbo-equipment designs through pressurization of the working fluid, and (3) to obtain relatively simple cycle configurations. The technical/economic performance of a specific closed cycle gas turbine system was evaluated through the development of a conceptual plant and system design. This energy conversion system is designed for electric utility service and to utilize coal directly in an environmentally acceptable manner.

Kinetics of the utilization of dietary arginine for nitric oxide and urea synthesis: insight into the arginine-nitric oxide metabolic system in humans.

PubMed

Mariotti, François; Petzke, Klaus J; Bonnet, Damien; Szezepanski, Isabelle; Bos, Cécile; Huneau, Jean-François; Fouillet, Hélène

2013-05-01

The systemic availability of oral/dietary arginine and its utilization for nitric oxide (NO) synthesis remains unknown and may be related to a competitive hydrolysis of arginine into urea in the splanchnic area and systemic circulation. We investigated the kinetics and dose-dependency of dietary arginine utilization for NO compared with urea synthesis and studied the characteristics of the arginine-NO metabolic system in healthy humans. We traced the metabolic fate and analyzed the utilization dynamics of dietary arginine after its ingestion at 2 nutritional amounts in healthy humans (n = 9) in a crossover design by using [(15)N-(15)N-(guanido)]-arginine, isotope ratio mass spectrometry techniques, and data analysis with a compartmental modeling approach. Whatever the amount of dietary arginine, 60 ± 3% (±SEM) was converted to urea, with kinetics indicative of a first-pass splanchnic phenomenon. Despite this dramatic extraction, intact dietary arginine made a major contribution to the postprandial increase in plasma arginine. However, the model identified that the plasma compartment was a very minor (~2%) precursor for the conversion of dietary arginine into NO, which, in any case, was small (<0.1% of the dose). The whole-body and plasma kinetics of arginine metabolism were consistent with the suggested competitive metabolism by the arginase and NO synthase pathways. The conversion of oral/dietary arginine into NO is not limited by the systemic availability of arginine but by a tight metabolic compartmentation at the systemic level. We propose an organization of the arginine metabolic system that explains the daily maintenance of NO homeostasis in healthy humans.

Development of a dual-field heteropoplar power converter

NASA Technical Reports Server (NTRS)

Eisenhaure, D. B.; Johnson, B.; Bliamptis, T.; St. George, E.

1981-01-01

The design and testing of a 400 watt, dual phase, dual rotor, field modulated inductor alternator is described. The system is designed for use as a flywheel to ac utility line or flywheel to dc bus (electric vehicle) power converter. The machine is unique in that it uses dual rotors and separately controlled fields to produce output current and voltage which are in phase with each other. Having the voltage and current in phase allows the power electronics to be made of simple low cost components. Based on analytical predictions and experimental results, development of a complete 22 kilowatt (30 Hp) power conversion system is recommended. This system would include power electronics and controls and would replace the inductor alternator with an improved electromagnetic conversion system.

Results of a utility survey of the status of large wind turbine development

NASA Technical Reports Server (NTRS)

Watts, A.; Quraeshi, S.; Rowley, L. P.

1979-01-01

Wind energy conversion systems were surveyed from a utility viewpoint to establish the state of the art with regard to: (1) availability of the type of machines; (2) quality of power generation; (3) suitability for electrical grid; (4) reliability; and (5) economics. Of the 23 designs discussed, 7 have vertical axis wind turbines, 9 have upwind horizontal axis turbines, and 7 have downwind horizontal axis turbines.

Can portable pyrolysis units make biomass utilization affordable while using bio-char to enhance soil productivity and sequester carbon?

Treesearch

Mark Coleman; Deborah Page-Dumroese; Jim Archuleta; Phil Badger; Woodum Chung; Tyron Venn; Dan Loeffler; Greg Jones; Kristin McElligott

2010-01-01

We describe a portable pyrolysis system for bioenergy production from forest biomass that minimizes long-distance transport costs and provides for nutrient return and long-term soil carbon storage. The cost for transporting biomass to conversion facilities is a major impediment to utilizing forest biomass. If forest biomass could be converted into bio-oil in the field...

SP-100 multimegawatt scaleup to meet electric propulsion mission requirements

NASA Astrophysics Data System (ADS)

Newkirk, D. W.; Salamah, S. A.; Stewart, S. L.; Pluta, P. R.

The SP-100 nuclear heat source technology, utilizing uranium nitride fuel clad in PWC-11 in a fast reactor with lithium coolant circulated by an electromagnetic pump, is shown to be directly extrapolatable to thermal power levels that meet NASA nuclear electric propulsion requirements using different power conversion techniques. The SP-100 nuclear technology can be applied to missions with NEP (nuclear electric propulsion) requirements as low as tens of kWe to tens of MWe. It is pointed out that the SP-100 heat source has a great advantage of very long lifetime capability, since it utilizes very rugged refractory metal fuel pins and is independent of the power conversion scheme chosen for a given mission. The only moving parts in the nuclear subsystems are the control rods moved to compensate for fuel enrichment degradation due to fission and for power shutdown. Lowest alpha values in the range of interest for potential NASA missions are predicted for the dynamic Rankine and static HYTEC conversion systems.

Effect of Solid-State Power-Converter Harmonics on Electric-Power-Supply Systems

DOT National Transportation Integrated Search

1973-03-01

The United States utility industry has not set suitable standards, other than TIF (Telephone Interference Factor), for controlling the design of solid-state wayside and on-board power-conversion equipment, to limit the harmonic currents and voltages ...

Utilization of non-conventional systems for conversion of biomass to food components: Potential for utilization of algae in engineered foods

NASA Technical Reports Server (NTRS)

Karel, M.; Kamarei, A. R.; Nakhost, Z.

1985-01-01

The major nutritional components of the green algae (Scenedesmus obliquus) grown in a Constant Cell density Apparatus were determined. Suitable methodology to prepare proteins from which three major undesirable components of these cells (i.e., cell walls, nucleic acids, and pigments) were either removed or substantially reduced was developed. Results showed that processing of green algae to protein isolate enhances its potential nutritional and organoleptic acceptability as a diet component in a Controlled Ecological Life Support System.

Clean fuels from biomass

NASA Technical Reports Server (NTRS)

Hsu, Y.-Y.

1976-01-01

The paper discusses the U.S. resources to provide fuels from agricultural products, the present status of conversion technology of clean fuels from biomass, and a system study directed to determine the energy budget, and environmental and socioeconomic impacts. Conversion processes are discussed relative to pyrolysis and anaerobic fermentation. Pyrolysis breaks the cellulose molecules to smaller molecules under high temperature in the absence of oxygen, wheras anaerobic fermentation is used to convert biomass to methane by means of bacteria. Cost optimization and energy utilization are also discussed.

Gas Turbine Energy Conversion Systems for Nuclear Power Plants Applicable to LiFTR Liquid Fluoride Thorium Reactor Technology

NASA Technical Reports Server (NTRS)

Juhasz, Albert J.

2014-01-01

This panel plans to cover thermal energy and electric power production issues facing our nation and the world over the next decades, with relevant technologies ranging from near term to mid-and far term.Although the main focus will be on ground based plants to provide baseload electric power, energy conversion systems (ECS) for space are also included, with solar- or nuclear energy sources for output power levels ranging tens of Watts to kilo-Watts for unmanned spacecraft, and eventual mega-Watts for lunar outposts and planetary surface colonies. Implications of these technologies on future terrestrial energy systems, combined with advanced fracking, are touched upon.Thorium based reactors, and nuclear fusion along with suitable gas turbine energy conversion systems (ECS) will also be considered by the panelists. The characteristics of the above mentioned ECS will be described, both in terms of their overall energy utilization effectiveness and also with regard to climactic effects due to exhaust emissions.

Two-Stage Variable Sample-Rate Conversion System

NASA Technical Reports Server (NTRS)

Tkacenko, Andre

2009-01-01

A two-stage variable sample-rate conversion (SRC) system has been pro posed as part of a digital signal-processing system in a digital com munication radio receiver that utilizes a variety of data rates. The proposed system would be used as an interface between (1) an analog- todigital converter used in the front end of the receiver to sample an intermediatefrequency signal at a fixed input rate and (2) digita lly implemented tracking loops in subsequent stages that operate at v arious sample rates that are generally lower than the input sample r ate. This Two-Stage System would be capable of converting from an input sample rate to a desired lower output sample rate that could be var iable and not necessarily a rational fraction of the input rate.

Efficient Design in a DC to DC Converter Unit

NASA Technical Reports Server (NTRS)

Bruemmer, Joel E.; Williams, Fitch R.; Schmitz, Gregory V.

2002-01-01

Space Flight hardware requires high power conversion efficiencies due to limited power availability and weight penalties of cooling systems. The International Space Station (ISS) Electric Power System (EPS) DC-DC Converter Unit (DDCU) power converter is no exception. This paper explores the design methods and tradeoffs that were utilized to accomplish high efficiency in the DDCU. An isolating DC to DC converter was selected for the ISS power system because of requirements for separate primary and secondary grounds and for a well-regulated secondary output voltage derived from a widely varying input voltage. A flyback-current-fed push-pull topology or improved Weinberg circuit was chosen for this converter because of its potential for high efficiency and reliability. To enhance efficiency, a non-dissipative snubber circuit for the very-low-Rds-on Field Effect Transistors (FETs) was utilized, redistributing the energy that could be wasted during the switching cycle of the power FETs. A unique, low-impedance connection system was utilized to improve contact resistance over a bolted connection. For improved consistency in performance and to lower internal wiring inductance and losses a planar bus system is employed. All of these choices contributed to the design of a 6.25 KW regulated dc to dc converter that is 95 percent efficient. The methodology used in the design of this DC to DC Converter Unit may be directly applicable to other systems that require a conservative approach to efficient power conversion and distribution.

Heat Exchanger Cleaning in Support of Ocean Thermal Energy Conversion (OTEC) - Mechanical Subsystem.

DTIC Science & Technology

1980-12-01

sponge rubber ball, and chlorination systems. In addition, the maintenance procedures utilized at the NCSC test site are provided. jAN 7 1473 EDITION OF...Recirculating Sponge Rubber Balls .. .... ............. 17 Chlorination .. .............. ............. 19 OTEC MAINTENANCE PROCEDURES...C-1 APPENDIX D - RECIRCULATING SPONGE RUBBER BALL. ............... D-1 APPENDIX E - CHLORINATION SYSTEM .. .. ................. E-1 i 1

Solar power satellite: System definition study. Part 1, volume 1: Executive summary

NASA Technical Reports Server (NTRS)

1977-01-01

A study of the solar power satellite system, which represents a means of tapping baseload electric utility power from the sun on a large scale, was summarized. Study objectives, approach, and planning are presented along with an energy conversion evaluation. Basic requirements were considered in regard to space transportation, construction, and maintainability.

100-kWe lunar/Mars surface power utilizing the SP-100 reactor with dynamic conversion

NASA Technical Reports Server (NTRS)

Harty, Richard B.; Mason, Lee S.

1992-01-01

Results are presented from a study of the coupling of an SP-100 nuclear reactor with either a Stirling or Brayton power system, at the 100 kWe level, for a power generating system suitable for operation in the lunar and Martian surface environments. In the lunar environment, the reactor and primary coolant loop would be contained in a guard vessel to protect from a loss of primary loop containment. For Mars, all refractory components, including the reactor, coolant, and power conversion components will be contained in a vacuum vessel for protection against the CO2 environment.

Efficient electrochemical CO 2 conversion powered by renewable energy

DOE PAGES

Kauffman, Douglas R.; Thakkar, Jay; Siva, Rajan; ...

2015-06-29

Here, the catalytic conversion of CO 2 into industrially relevant chemicals is one strategy for mitigating greenhouse gas emissions. Along these lines, electrochemical CO 2 conversion technologies are attractive because they can operate with high reaction rates at ambient conditions. However, electrochemical systems require electricity, and CO 2 conversion processes must integrate with carbon-free, renewable-energy sources to be viable on larger scales. We utilize Au 25 nanoclusters as renewably powered CO 2 conversion electrocatalysts with CO 2 → CO reaction rates between 400 and 800 L of CO 2 per gram of catalytic metal per hour and product selectivities betweenmore » 80 and 95%. These performance metrics correspond to conversion rates approaching 0.8–1.6 kg of CO 2 per gram of catalytic metal per hour. We also present data showing CO 2 conversion rates and product selectivity strongly depend on catalyst loading. Optimized systems demonstrate stable operation and reaction turnover numbers (TONs) approaching 6 × 10 6 mol CO 2 molcatalyst–1 during a multiday (36 hours total hours) CO 2electrolysis experiment containing multiple start/stop cycles. TONs between 1 × 10 6 and 4 × 10 6 molCO 2 molcatalyst–1 were obtained when our system was powered by consumer-grade renewable-energy sources. Daytime photovoltaic-powered CO 2 conversion was demonstrated for 12 h and we mimicked low-light or nighttime operation for 24 h with a solar-rechargeable battery. This proof-of-principle study provides some of the initial performance data necessary for assessing the scalability and technical viability of electrochemical CO 2 conversion technologies. Specifically, we show the following: (1) all electrochemical CO 2 conversion systems will produce a net increase in CO 2 emissions if they do not integrate with renewable-energy sources, (2) catalyst loading vs activity trends can be used to tune process rates and product distributions, and (3) state-of-the-art renewable-energy technologies are sufficient to power larger-scale, tonne per day CO 2 conversion systems.« less

Study of the generator/motor operation of induction machines in a high frequency link space power system

NASA Technical Reports Server (NTRS)

Lipo, Thomas A.; Sood, Pradeep K.

1987-01-01

Static power conversion systems have traditionally utilized dc current or voltage source links for converting power from one ac or dc form to another since it readily achieves the temporary energy storage required to decouple the input from the output. Such links, however, result in bulky dc capacitors and/or inductors and lead to relatively high losses in the converters due to stresses on the semiconductor switches. The feasibility of utilizing a high frequency sinusoidal voltage link to accomplish the energy storage and decoupling function is examined. In particular, a type of resonant six pulse bridge interface converter is proposed which utilizes zero voltage switching principles to minimize switching losses and uses an easy to implement technique for pulse density modulation to control the amplitude, frequency, and the waveshape of the synthesized low frequency voltage or current. Adaptation of the proposed topology for power conversion to single-phase ac and dc voltage or current outputs is shown to be straight forward. The feasibility of the proposed power circuit and control technique for both active and passive loads are verified by means of simulation and experiment.

High resolution A/D conversion based on piecewise conversion at lower resolution

DOEpatents

Terwilliger, Steve [Albuquerque, NM

2012-06-05

Piecewise conversion of an analog input signal is performed utilizing a plurality of relatively lower bit resolution A/D conversions. The results of this piecewise conversion are interpreted to achieve a relatively higher bit resolution A/D conversion without sampling frequency penalty.

Optimal Design of Biomass Utilization System for Rural Area Includes Technical and Economic Dimensions

NASA Astrophysics Data System (ADS)

Morioka, Yasuki; Nakata, Toshihiko

In order to design optimal biomass utilization system for rural area, OMNIBUS (The Optimization Model for Neo-Integrated Biomass Utilization System) has been developed. OMNIBUS can derive the optimal system configuration to meet different objective function, such as current account balance, amount of biomass energy supply, and CO2 emission. Most of biomass resources in a focused region e.g. wood biomass, livestock biomass, and crop residues are considered in the model. Conversion technologies considered are energy utilization technologies e.g. direct combustion and methane fermentation, and material utilization technologies e.g. composting and carbonization. Case study in Miyakojima, Okinawa prefecture, has been carried out for several objective functions and constraint conditions. Considering economics of the utilization system as a priority requirement, composting and combustion heat utilization are mainly chosen in the optimal system configuration. However gasification power plant and methane fermentation are included in optimal solutions, only when both biomass energy utilization and CO2 reduction have been set as higher priorities. External benefit of CO2 reduction has large impacts on the system configuration. Provided marginal external benefit of more than 50,000 JPY/t-C, external benefit becomes greater than the revenue from electricity and compost etc. Considering technological learning in the future, expensive technologies such as gasification power plant and methane fermentation will have economic feasibility as well as market competitiveness.

Development of a low cost integrated 15 kW A.C. solar tracking sub-array for grid connected PV power system applications

NASA Astrophysics Data System (ADS)

Stern, M.; West, R.; Fourer, G.; Whalen, W.; Van Loo, M.; Duran, G.

1997-02-01

Utility Power Group has achieved a significant reduction in the installed cost of grid-connected PV systems. The two part technical approach focused on 1) The utilization of a large area factory assembled PV panel, and 2) The integration and packaging of all sub-array power conversion and control functions within a single factory produced enclosure. Eight engineering prototype 15kW ac single axis solar tracking sub-arrays were designed, fabricated, and installed at the Sacramento Municipal Utility District's Hedge Substation site in 1996 and are being evaluated for performance and reliability. A number of design enhancements will be implemented in 1997 and demonstrated by the field deployment and operation of over twenty advanced sub-array PV power systems.

Cogeneration Technology Alternatives Study (CTAS). Volume 3: Energy conversion system characteristics

NASA Technical Reports Server (NTRS)

1980-01-01

Six current and thirty-six advanced energy conversion systems were defined and combined with appropriate balance of plant equipment. Twenty-six industrial processes were selected from among the high energy consuming industries to serve as a frame work for the study. Each conversion system was analyzed as a cogenerator with each industrial plant. Fuel consumption, costs, and environmental intrusion were evaluated and compared to corresponding traditional values. The advanced energy conversion technologies indicated reduced fuel consumption, costs, and emissions. Fuel energy savings of 10 to 25 percent were predicted compared to traditional on site furnaces and utility electricity. With the variety of industrial requirements, each advanced technology had attractive applications. Fuel cells indicated the greatest fuel energy savings and emission reductions. Gas turbines and combined cycles indicated high overall annual savings. Steam turbines and gas turbines produced high estimated returns. In some applications, diesels were most efficient. The advanced technologies used coal derived fuels, or coal with advanced fluid bed combustion or on site gasifications. Data and information for both current and advanced energy conversion technology are presented. Schematic and physical descriptions, performance data, equipment cost estimates, and predicted emissions are included. Technical developments which are needed to achieve commercialization in the 1985-2000 period are identified.

Building carbon–carbon bonds using a biocatalytic methanol condensation cycle

PubMed Central

Bogorad, Igor W.; Chen, Chang-Ting; Theisen, Matthew K.; Wu, Tung-Yun; Schlenz, Alicia R.; Lam, Albert T.; Liao, James C.

2014-01-01

Methanol is an important intermediate in the utilization of natural gas for synthesizing other feedstock chemicals. Typically, chemical approaches for building C–C bonds from methanol require high temperature and pressure. Biological conversion of methanol to longer carbon chain compounds is feasible; however, the natural biological pathways for methanol utilization involve carbon dioxide loss or ATP expenditure. Here we demonstrated a biocatalytic pathway, termed the methanol condensation cycle (MCC), by combining the nonoxidative glycolysis with the ribulose monophosphate pathway to convert methanol to higher-chain alcohols or other acetyl-CoA derivatives using enzymatic reactions in a carbon-conserved and ATP-independent system. We investigated the robustness of MCC and identified operational regions. We confirmed that the pathway forms a catalytic cycle through 13C-carbon labeling. With a cell-free system, we demonstrated the conversion of methanol to ethanol or n-butanol. The high carbon efficiency and low operating temperature are attractive for transforming natural gas-derived methanol to longer-chain liquid fuels and other chemical derivatives. PMID:25355907

Conceptual design of an advanced Stirling conversion system for terrestrial power generation

NASA Technical Reports Server (NTRS)

1988-01-01

A free piston Stirling engine coupled to an electric generator or alternator with a nominal kWe power output absorbing thermal energy from a nominal 100 square meter parabolic solar collector and supplying electric power to a utility grid was identified. The results of the conceptual design study of an Advanced Stirling Conversion System (ASCS) were documented. The objectives are as follows: define the ASCS configuration; provide a manufacturability and cost evaluation; predict ASCS performance over the range of solar input required to produce power; estimate system and major component weights; define engine and electrical power condidtioning control requirements; and define key technology needs not ready by the late 1980s in meeting efficiency, life, cost, and with goalds for the ASCS.

Combustion pinhole-camera system

DOEpatents

Witte, A.B.

1982-05-19

A pinhole camera system is described utilizing a sealed optical-purge assembly which provides optical access into a coal combustor or other energy conversion reactors. The camera system basically consists of a focused-purge pinhole optical port assembly, a conventional TV vidicon receiver, an external, variable density light filter which is coupled electronically to the vidicon automatic gain control (agc). The key component of this system is the focused-purge pinhole optical port assembly which utilizes a purging inert gas to keep debris from entering the port and a lens arrangement which transfers the pinhole to the outside of the port assembly. One additional feature of the port assembly is that it is not flush with the interior of the combustor.

Combustion pinhole camera system

DOEpatents

Witte, A.B.

1984-02-21

A pinhole camera system is described utilizing a sealed optical-purge assembly which provides optical access into a coal combustor or other energy conversion reactors. The camera system basically consists of a focused-purge pinhole optical port assembly, a conventional TV vidicon receiver, an external, variable density light filter which is coupled electronically to the vidicon automatic gain control (agc). The key component of this system is the focused-purge pinhole optical port assembly which utilizes a purging inert gas to keep debris from entering the port and a lens arrangement which transfers the pinhole to the outside of the port assembly. One additional feature of the port assembly is that it is not flush with the interior of the combustor. 2 figs.

Combustion pinhole camera system

DOEpatents

Witte, Arvel B.

1984-02-21

A pinhole camera system utilizing a sealed optical-purge assembly which provides optical access into a coal combustor or other energy conversion reactors. The camera system basically consists of a focused-purge pinhole optical port assembly, a conventional TV vidicon receiver, an external, variable density light filter which is coupled electronically to the vidicon automatic gain control (agc). The key component of this system is the focused-purge pinhole optical port assembly which utilizes a purging inert gas to keep debris from entering the port and a lens arrangement which transfers the pinhole to the outside of the port assembly. One additional feature of the port assembly is that it is not flush with the interior of the combustor.

Instructional Investment or Administrative Bloat: The Effects of Charter System Conversion on Resource Allocations and Staffing Patterns

ERIC Educational Resources Information Center

Kramer, Dennis A., II; Lane, Megan; Tanner, Melvin

2017-01-01

Despite the growing call for local autonomy and flexibility, few scholars have examined the role of school district-level flexibility on resource allocation and staffing patterns. Leveraging the charter system law within the State of Georgia, we utilize a generalized difference-in-differences approach to estimate the impact of flexibility of…

Fossil Energy Program

NASA Astrophysics Data System (ADS)

McNeese, L. E.

1981-01-01

Increased utilization of coal and other fossil fuel alternatives as sources of clean energy is reported. The following topics are discussed: coal conversion development, chemical research and development, materials technology, component development and process evaluation studies, technical support to major liquefaction projects, process analysis and engineering evaluations, fossil energy environmental analysis, flue gas desulfurization, solid waste disposal, coal preparation waste utilization, plant control development, atmospheric fluidized bed coal combustor for cogeneration, TVA FBC demonstration plant program technical support, PFBC systems analysis, fossil fuel applications assessments, performance assurance system support for fossil energy projects, international energy technology assessment, and general equilibrium models of liquid and gaseous fuel supplies.

Satellite Power Systems (SPS) Concept Definition Study. Volume 3: SPS Concept Evolution

NASA Technical Reports Server (NTRS)

Hanley, G.

1978-01-01

A solar photovoltaic satellite based upon the utilization of a GaAlAs solar cell is defined. Topics covered include silicon-based photovoltaics, solar thermal power conversion, microwave energy transmission, power distribution, structures, attitude control and stationkeeping, thermal, and information management and control.

Method of preparing and utilizing a catalyst system for an oxidation process on a gaseous hydrocarbon stream

DOEpatents

Berry, David A; Shekhawat, Dushyant; Smith, Mark; Haynes, Daniel

2013-07-16

The disclosure relates to a method of utilizing a catalyst system for an oxidation process on a gaseous hydrocarbon stream with a mitigation of carbon accumulation. The system is comprised of a catalytically active phase deposited onto an oxygen conducting phase, with or without supplemental support. The catalytically active phase has a specified crystal structure where at least one catalytically active metal is a cation within the crystal structure and coordinated with oxygen atoms within the crystal structure. The catalyst system employs an optimum coverage ratio for a given set of oxidation conditions, based on a specified hydrocarbon conversion and a carbon deposition limit. Specific embodiments of the catalyst system are disclosed.

Ethanol production from renewable resources.

PubMed

Gong, C S; Cao, N J; Du, J; Tsao, G T

1999-01-01

Vast amounts of renewable biomass are available for conversion to liquid fuel, ethanol. In order to convert biomass to ethanol, the efficient utilization of both cellulose-derived and hemicellulose-derived carbohydrates is essential. Six-carbon sugars are readily utilized for this purpose. Pentoses, on the other hand, are more difficult to convert. Several metabolic factors limit the efficient utilization of pentoses (xylose and arabinose). Recent developments in the improvement of microbial cultures provide the versatility of conversion of both hexoses and pentoses to ethanol more efficiently. In addition, novel bioprocess technologies offer a promising prospective for the efficient conversion of biomass and recovery of ethanol.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chamana, Manohar; Prabakar, Kumaraguru; Palmintier, Bryan

A software process is developed to convert distribution network models from a quasi-static time-series tool (OpenDSS) to a real-time dynamic phasor simulator (ePHASORSIM). The description of this process in this paper would be helpful for researchers who intend to perform similar conversions. The converter could be utilized directly by users of real-time simulators who intend to perform software-in-the-loop or hardware-in-the-loop tests on large distribution test feeders for a range of use cases, including testing functions of advanced distribution management systems against a simulated distribution system. In the future, the developers intend to release the conversion tool as open source tomore » enable use by others.« less

Monolithic Interconnected Modules (MIMs) for Thermophotovoltaic Energy Conversion

NASA Technical Reports Server (NTRS)

Wilt, David; Wehrer, Rebecca; Palmisiano, Marc; Wanlass, Mark; Murray, Christopher

2003-01-01

Monolithic Interconnected Modules (MIM) are under development for thermophotovoltaic (TPV) energy conversion applications. MIM devices are typified by series-interconnected photovoltaic cells on a common, semi-insulating substrate and generally include rear-surface infrared (IR) reflectors. The MIM architecture is being implemented in InGaAsSb materials without semi-insulating substrates through the development of alternative isolation methodologies. Motivations for developing the MIM structure include: reduced resistive losses, higher output power density than for systems utilizing front surface spectral control, improved thermal coupling and ultimately higher system efficiency. Numerous design and material changes have been investigated since the introduction of the MIM concept in 1994. These developments as well as the current design strategies are addressed.

Optical Frequency Optimization of a High Intensity Laser Power Beaming System Utilizing VMJ Photovoltaic Cells

NASA Technical Reports Server (NTRS)

Raible, Daniel E.; Dinca, Dragos; Nayfeh, Taysir H.

2012-01-01

An effective form of wireless power transmission (WPT) has been developed to enable extended mission durations, increased coverage and added capabilities for both space and terrestrial applications that may benefit from optically delivered electrical energy. The high intensity laser power beaming (HILPB) system enables long range optical 'refueling" of electric platforms such as micro unmanned aerial vehicles (MUAV), airships, robotic exploration missions and spacecraft platforms. To further advance the HILPB technology, the focus of this investigation is to determine the optimal laser wavelength to be used with the HILPB receiver, which utilizes vertical multi-junction (VMJ) photovoltaic cells. Frequency optimization of the laser system is necessary in order to maximize the conversion efficiency at continuous high intensities, and thus increase the delivered power density of the HILPB system. Initial spectral characterizations of the device performed at the NASA Glenn Research Center (GRC) indicate the approximate range of peak optical-to-electrical conversion efficiencies, but these data sets represent transient conditions under lower levels of illumination. Extending these results to high levels of steady state illumination, with attention given to the compatibility of available commercial off-the-shelf semiconductor laser sources and atmospheric transmission constraints is the primary focus of this paper. Experimental hardware results utilizing high power continuous wave (CW) semiconductor lasers at four different operational frequencies near the indicated band gap of the photovoltaic VMJ cells are presented and discussed. In addition, the highest receiver power density achieved to date is demonstrated using a single photovoltaic VMJ cell, which provided an exceptionally high electrical output of 13.6 W/sq cm at an optical-to-electrical conversion efficiency of 24 percent. These results are very promising and scalable, as a potential 1.0 sq m HILPB receiver of similar construction would be able to generate 136 kW of electrical power under similar conditions.

Comparative performance of solar thermal power generation concepts

NASA Technical Reports Server (NTRS)

Wen, L.; Wu, Y. C.

1976-01-01

A performance comparison is made between the central receiver system (power tower) and a distributed system using either dishes or troughs and lines to transport fluids to the power station. These systems were analyzed at a rated capacity of 30 MW of thermal energy delivered in the form of superheated steam at 538 C (1000 F) and 68 atm (1000 psia), using consistent weather data, collector surface waviness, pointing error, and electric conversion efficiency. The comparisons include technical considerations for component requirements, land utilization, and annual thermal energy collection rates. The relative merits of different representative systems are dependent upon the overall conversion as expressed in the form of performance factors in this paper. These factors are essentially indices of the relative performance effectiveness for different concepts based upon unit collector area. These performance factors enable further economic tradeoff studies of systems to be made by comparing them with projected production costs for these systems.

Cogeneration technology alternatives study. Volume 1: Summary report

NASA Technical Reports Server (NTRS)

1980-01-01

Data and information in the area of advanced energy conversion systems for industrial congeneration applications in the 1985-2000 time period was studied. Six current and thirty-one advanced energy conversion systems were defined and combined with appropriate balance-of-plant equipment. Twenty-six industrial processes were selected from among the high energy consuming industries to serve as a framework for the study. Each conversion system was analyzed as a cogenerator with each industrial plant. Fuel consumption, costs, and environmental intrusion were evaluated and compared to corresponding traditional values. Various cogeneration strategies were analyzed and both topping and bottoming (using industrial by-product heat) applications were included. The advanced energy conversion technologies indicated reduced fuel consumption, costs, and emissions. Typically fuel energy savings of 10 to 25 percent were predicted compared to traditional on-site furnaces and utility electricity. With the variety of industrial requirements, each advanced technology had attractive applications. Overall, fuel cells indicated the greatest fuel energy savings and emission reductions. Gas turbines and combined cycles indicated high overall annual cost savings. Steam turbines and gas turbines produced high estimated returns. In some applications, diesels were most efficient. The advanced technologies used coal-derived fuels, or coal with advanced fluid bed combustion or on-site gasification systems.

Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 2: Materials considerations. [materials used in boilers and heat exchangers of energy conversion systems for electric power plants using coal

NASA Technical Reports Server (NTRS)

Thomas, D. E.

1976-01-01

Extensive studies are presented which were carried out on materials behavior in nine advanced energy conversion systems employing coal and coal-derived fuels. The areas of materials behavior receiving particular attention in this regard are: (1) fireside corrosion and erosion in boiler and heat exchanger materials, (2) oxidation and hot corrosion of gas turbine materials, (3) liquid metal corrosion and mass transport, (4) high temperature steam corrosion, (5) compatability of materials with coal slag and MHD seed, (6) reaction of materials with impure helium, (7) allowable stresses for boiler and heat exchanger materials, (8) environmental effects on mechanical properties, and (9) liquid metal purity control and instrumentation. Such information was then utilized in recommending materials for use in the critical components of the power systems, and at the same time to identify materials problem areas and to evaluate qualitatively the difficulty of solving those problems. Specific materials recommendations for critical components of the nine advanced systems under study are contained in summary tables.

Reliability Issues in Stirling Radioisotope Power Systems

NASA Technical Reports Server (NTRS)

Schreiber, Jeffrey; Shah, Ashwin

2005-01-01

Stirling power conversion is a potential candidate for use in a Radioisotope Power System (RPS) for space science missions because it offers a multifold increase in the conversion efficiency of heat to electric power and reduced requirement of radioactive material. Reliability of an RPS that utilizes Stirling power conversion technology is important in order to ascertain long term successful performance. Owing to long life time requirement (14 years), it is difficult to perform long-term tests that encompass all the uncertainties involved in the design variables of components and subsystems comprising the RPS. The requirement for uninterrupted performance reliability and related issues are discussed, and some of the critical areas of concern are identified. An overview of the current on-going efforts to understand component life, design variables at the component and system levels, and related sources and nature of uncertainties are also discussed. Current status of the 110 watt Stirling Radioisotope Generator (SRG110) reliability efforts is described. Additionally, an approach showing the use of past experience on other successfully used power systems to develop a reliability plan for the SRG110 design is outlined.

Reliability Issues in Stirling Radioisotope Power Systems

NASA Technical Reports Server (NTRS)

Shah, Ashwin R.; Schreiber, Jeffrey G.

2004-01-01

Stirling power conversion is a potential candidate for use in a Radioisotope Power System (RPS) for space science missions because it offers a multifold increase in the conversion efficiency of heat to electric power and reduced requirement of radioactive material. Reliability of an RPS that utilizes Stirling power conversion technology is important in order to ascertain long term successful performance. Owing to long life time requirement (14 years), it is difficult to perform long-term tests that encompass all the uncertainties involved in the design variables of components and subsystems comprising the RPS. The requirement for uninterrupted performance reliability and related issues are discussed, and some of the critical areas of concern are identified. An overview of the current on-going efforts to understand component life, design variables at the component and system levels, and related sources and nature of uncertainties are also discussed. Current status of the 110 watt Stirling Radioisotope Generator (SRG110) reliability efforts is described. Additionally, an approach showing the use of past experience on other successfully used power systems to develop a reliability plan for the SRG110 design is outlined.

Spruce Budworm and Energy Metabolism?

Treesearch

Thakor R.  Patel

1983-01-01

The utilization of stored lipids (fat) for energy metabolism appears to be a fundamental process for many biological systems especially during the early stages of their development. The participation of the glyoxylate cycle (GOG) together with other metabolic sequences like gluconeogenesis and beta oxidation are necessary for the conversion of lipids to carbohydrates....

24 CFR 965.404 - Order of conversion.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Order of conversion. 965.404...-Owned Projects § 965.404 Order of conversion. Conversions to individually metered utility service shall... be analyzed both for the installation of checkmeters and for conversion to retail service. (d) Low...

24 CFR 965.404 - Order of conversion.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Order of conversion. 965.404...-Owned Projects § 965.404 Order of conversion. Conversions to individually metered utility service shall... be analyzed both for the installation of checkmeters and for conversion to retail service. (d) Low...

High Temperature Fusion Reactor Cooling Using Brayton Cycle Based Partial Energy Conversion

NASA Technical Reports Server (NTRS)

Juhasz, Albert J.; Sawicki, Jerzy T.

2003-01-01

For some future space power systems using high temperature nuclear heat sources most of the output energy will be used in other than electrical form, and only a fraction of the total thermal energy generated will need to be converted to electrical work. The paper describes the conceptual design of such a partial energy conversion system, consisting of a high temperature fusion reactor operating in series with a high temperature radiator and in parallel with dual closed cycle gas turbine (CCGT) power systems, also referred to as closed Brayton cycle (CBC) systems, which are supplied with a fraction of the reactor thermal energy for conversion to electric power. Most of the fusion reactor's output is in the form of charged plasma which is expanded through a magnetic nozzle of the interplanetary propulsion system. Reactor heat energy is ducted to the high temperature series radiator utilizing the electric power generated to drive a helium gas circulation fan. In addition to discussing the thermodynamic aspects of the system design the authors include a brief overview of the gas turbine and fan rotor-dynamics and proposed bearing support technology along with performance characteristics of the three phase AC electric power generator and fan drive motor.

High Temperature Fusion Reactor Cooling Using Brayton Cycle Based Partial Energy Conversion

NASA Astrophysics Data System (ADS)

Juhasz, Albert J.; Sawicki, Jerzy T.

2004-02-01

For some future space power systems using high temperature nuclear heat sources most of the output energy will be used in other than electrical form, and only a fraction of the total thermal energy generated will need to be converted to electrical work. The paper describes the conceptual design of such a ``partial energy conversion'' system, consisting of a high temperature fusion reactor operating in series with a high temperature radiator and in parallel with dual closed cycle gas turbine (CCGT) power systems, also referred to as closed Brayton cycle (CBC) systems, which are supplied with a fraction of the reactor thermal energy for conversion to electric power. Most of the fusion reactor's output is in the form of charged plasma which is expanded through a magnetic nozzle of the interplanetary propulsion system. Reactor heat energy is ducted to the high temperature series radiator utilizing the electric power generated to drive a helium gas circulation fan. In addition to discussing the thermodynamic aspects of the system design the authors include a brief overview of the gas turbine and fan rotor-dynamics and proposed bearing support technology along with performance characteristics of the three phase AC electric power generator and fan drive motor.

A preliminary assessment of the feasibility of deriving liquid and gaseous fuels from grown and waste organics

NASA Technical Reports Server (NTRS)

Graham, R. W.; Reynolds, T. W.; Hsu, Y.-Y.

1976-01-01

An estimate is obtained of the yearly supply of organic material for conversion to fuels, the energy potential is evaluated, and the fermentation and pyrolysis conversion processes are discussed. An investigation is conducted of the estimated cost of fuel from organics and the conclusions of an overall evaluation are presented. It is found that climate, land availability and economics of agricultural production and marketing, food demand, fertilizer shortage, and water availability combine to cast doubts on the feasibility of producing grown organic matter for fuel, in competition with food, feed, or fiber. Less controversial is the utilization of agricultural, industrial, and domestic waste as a conversion feedstock. The evaluation of a demonstration size system is recommended.

Fair Oaks Dairy Farms Cellulosic Ethanol Technology Review Summary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andrew Wold; Robert Divers

2011-06-23

At Fair Oaks Dairy, dried manure solids (''DMS'') are currently used as a low value compost. United Power was engaged to evaluate the feasibility of processing these DMS into ethanol utilizing commercially available cellulosic biofuels conversion platforms. The Fair Oaks Dairy group is transitioning their traditional ''manure to methane'' mesophilic anaerobic digester platform to an integrated bio-refinery centered upon thermophilic digestion. Presently, the Digested Manure Solids (DMS) are used as a low value soil amendment (compost). United Power evaluated the feasibility of processing DMS into higher value ethanol utilizing commercially available cellulosic biofuels conversion platforms. DMS was analyzed and overmore » 100 potential technology providers were reviewed and evaluated. DMS contains enough carbon to be suitable as a biomass feedstock for conversion into ethanol by gasification technology, or as part of a conversion process that would include combined heat and power. In the first process, 100% of the feedstock is converted into ethanol. In the second process, the feedstock is combusted to provide heat to generate electrical power supporting other processes. Of the 100 technology vendors evaluated, a short list of nine technology providers was developed. From this, two vendors were selected as finalists (one was an enzymatic platform and one was a gasification platform). Their selection was based upon the technical feasibility of their systems, engineering expertise, experience in commercial or pilot scale operations, the ability or willingness to integrate the system into the Fair Oaks Biorefinery, the know-how or experience in producing bio-ethanol, and a clear path to commercial development.« less

Research and evaluation of biomass resources/conversion/utilization systems (market/experimental analysis for development of a data base for a fuels from biomass model. Volume I. Biomass allocation model. Technical progress report for the period ending September 30, 1980

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahn, Y.K.; Chen, H.T.; Helm, R.W.

1980-01-01

A biomass allocation model has been developed to show the most profitable combination of biomass feedstocks thermochemical conversion processes, and fuel products to serve the seasonal conditions in a regional market. This optimization model provides a tool for quickly calculating the most profitable biomass missions from a large number of potential biomass missions. Other components of the system serve as a convenient storage and retrieval mechanism for biomass marketing and thermochemical conversion processing data. The system can be accessed through the use of a computer terminal, or it could be adapted to a portable micro-processor. A User's Manual for themore » system has been included in Appendix A of the report. The validity of any biomass allocation solution provided by the allocation model is dependent on the accuracy of the data base. The initial data base was constructed from values obtained from the literature, and, consequently, as more current thermochemical conversion processing and manufacturing costs and efficiencies become available, the data base should be revised. Biomass derived fuels included in the data base are the following: medium Btu gas low Btu gas, substitute natural gas, ammonia, methanol, electricity, gasoline, and fuel oil. The market sectors served by the fuels include: residential, electric utility, chemical (industrial), and transportation. Regional/seasonal costs and availabilities and heating values for 61 woody and non-woody biomass species are included. The study has included four regions in the United States which were selected because there was both an availability of biomass and a commercial demand for the derived fuels: Region I: NY, WV, PA; Region II: GA, AL, MS; Region III: IN, IL, IA; and Region IV: OR, WA.« less

Recombinant thermoactive phosphoenolpyruvate carboxylase (PEPC) from Thermosynechococcus elongatus and its coupling with mesophilic/thermophilic bacterial carbonic anhydrases (CAs) for the conversion of CO2 to oxaloacetate.

PubMed

Del Prete, Sonia; De Luca, Viviana; Capasso, Clemente; Supuran, Claudiu T; Carginale, Vincenzo

2016-01-15

With the continuous increase of atmospheric CO2 in the last decades, efficient methods for carbon capture, sequestration, and utilization are urgently required. The possibility of converting CO2 into useful chemicals could be a good strategy to both decreasing the CO2 concentration and for achieving an efficient exploitation of this cheap carbon source. Recently, several single- and multi-enzyme systems for the catalytic conversion of CO2 mainly to bicarbonate have been implemented. In order to design and construct a catalytic system for the conversion of CO2 to organic molecules, we implemented an in vitro multienzyme system using mesophilic and thermophilic enzymes. The system, in fact, was constituted by a recombinant phosphoenolpyruvate carboxylase (PEPC) from the thermophilic cyanobacterium Thermosynechococcus elongatus, in combination with mesophilic/thermophilic bacterial carbonic anhydrases (CAs), for converting CO2 into oxaloacetate, a compound of potential utility in industrial processes. The catalytic procedure is in two steps: the conversion of CO2 into bicarbonate by CA, followed by the carboxylation of phosphoenolpyruvate with bicarbonate, catalyzed by PEPC, with formation of oxaloacetate (OAA). All tested CAs, belonging to α-, β-, and γ-CA classes, were able to increase OAA production compared to procedures when only PEPC was used. Interestingly, the efficiency of the CAs tested in OAA production was in good agreement with the kinetic parameters for the CO2 hydration reaction of these enzymes. This PEPC also revealed to be thermoactive and thermostable, and when coupled with the extremely thermostable CA from Sulphurhydrogenibium azorense (SazCA) the production of OAA was achieved even if the two enzymes were exposed to temperatures up to 60 °C, suggesting a possible role of the two coupled enzymes in biotechnological processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nanotechnology and clean energy: sustainable utilization and supply of critical materials

NASA Astrophysics Data System (ADS)

Fromer, Neil A.; Diallo, Mamadou S.

2013-11-01

Advances in nanoscale science and engineering suggest that many of the current problems involving the sustainable utilization and supply of critical materials in clean and renewable energy technologies could be addressed using (i) nanostructured materials with enhanced electronic, optical, magnetic and catalytic properties and (ii) nanotechnology-based separation materials and systems that can recover critical materials from non-traditional sources including mine tailings, industrial wastewater and electronic wastes with minimum environmental impact. This article discusses the utilization of nanotechnology to improve or achieve materials sustainability for energy generation, conversion and storage. We highlight recent advances and discuss opportunities of utilizing nanotechnology to address materials sustainability for clean and renewable energy technologies.

Final design of a free-piston hydraulic advanced Stirling conversion system

NASA Technical Reports Server (NTRS)

Wallace, D. A.; Noble, J. E.; Emigh, S. G.; Ross, B. A.; Lehmann, G. A.

1991-01-01

Under the US Department of Energy's (DOEs) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for solar distributed receiver systems. The final design is described of an engineering prototype advanced Stirling conversion system (ASCS) with a free-piston hydraulic engine output capable of delivering about 25 kW of electric power to a utility grid. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, has noncontacting bearings, and can be hermetically sealed. The ASCS is designed to deliver maximum power per year over a range of solar input with a design life of 30 years (60,000 h). The system includes a liquid Nak pool boiler heat transport system and a free-piston Stirling engine with high-pressure hydraulic output, coupled with a bent axis variable displacement hydraulic motor and a rotary induction generator.

Nuclear power propulsion system for spacecraft

NASA Astrophysics Data System (ADS)

Koroteev, A. S.; Oshev, Yu. A.; Popov, S. A.; Karevsky, A. V.; Solodukhin, A. Ye.; Zakharenkov, L. E.; Semenkin, A. V.

2015-12-01

The proposed designs of high-power space tugs that utilize solar or nuclear energy to power an electric jet engine are reviewed. The conceptual design of a nuclear power propulsion system (NPPS) is described; its structural diagram, gas circuit, and electric diagram are discussed. The NPPS incorporates a nuclear reactor, a thermal-to-electric energy conversion system, a system for the conversion and distribution of electric energy, and an electric propulsion system. Two criterion parameters were chosen in the considered NPPS design: the temperature of gaseous working medium at the nuclear reactor outlet and the rotor speed of turboalternators. The maintenance of these parameters at a given level guarantees that the needed electric voltage is generated and allows for power mode control. The processes of startup/shutdown and increasing/reducing the power, the principles of distribution of electric energy over loads, and the probable emergencies for the proposed NPPS design are discussed.

Final design of a free-piston hydraulic advanced Stirling conversion system

NASA Astrophysics Data System (ADS)

Wallace, D. A.; Noble, J. E.; Emigh, S. G.; Ross, B. A.; Lehmann, G. A.

Under the US Department of Energy's (DOEs) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for solar distributed receiver systems. The final design is described of an engineering prototype advanced Stirling conversion system (ASCS) with a free-piston hydraulic engine output capable of delivering about 25 kW of electric power to a utility grid. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, has noncontacting bearings, and can be hermetically sealed. The ASCS is designed to deliver maximum power per year over a range of solar input with a design life of 30 years (60,000 h). The system includes a liquid Nak pool boiler heat transport system and a free-piston Stirling engine with high-pressure hydraulic output, coupled with a bent axis variable displacement hydraulic motor and a rotary induction generator.

Impact of alternative energy forms on public utilities

NASA Technical Reports Server (NTRS)

Keith, F. W., Jr.

1977-01-01

The investigation of alternative energy sources by the electric utility industry is discussed. Research projects are reviewed in each of the following areas; solar energy, wind energy conversion, photosynthesis of biomass, ocean thermal energy conversion, geothermal energy, fusion, and the environmental impact of alternative energy sources.

Energy recovery from waste glycerol by utilizing thermal water vapor plasma.

PubMed

Tamošiūnas, Andrius; Valatkevičius, Pranas; Gimžauskaitė, Dovilė; Jeguirim, Mejdi; Mėčius, Vladas; Aikas, Mindaugas

2017-04-01

Glycerol, considered as a waste feedstock resulting from biodiesel production, has received much attention in recent years due to its properties, which offer to recover energy. The aim of this study was to investigate the use of a thermal water vapor plasma for waste (crude) glycerol conversion to synthesis gas, or syngas (H 2  + CO). In parallel of crude glycerol, a pure glycerol (99.5%) was used as a reference material in order to compare the concentrations of the formed product gas. A direct current (DC) arc plasma torch stabilized by a mixture of argon/water vapor was utilized for the effective glycerol conversion to hydrogen-rich synthesis gas. It was found that after waste glycerol treatment, the main reaction products were gases with corresponding concentrations of H 2 50.7%, CO 23.53%, CO 2 11.45%, and CH 4 3.82%, and traces of C 2 H 2 and C 2 H 6 , which concentrations were below 0.5%. The comparable concentrations of the formed gas products were obtained after pure glycerol conversion-H 2 46.4%, CO 26.25%, CO 2 11.3%, and CH 4 4.7%. The use of thermal water vapor plasma producing synthesis gas is an effective method to recover energy from both crude and pure glycerol. The performance of the glycerol conversion system was defined in terms of the produced gas yield, the carbon conversion efficiency, the cold gas efficiency, and the specific energy requirements.

Translating Benzodiazepine Utilization Data into Meaningful Population Exposure: Integration of Two Metrics for Improved Reporting.

PubMed

Brandt, Jaden; Alkabanni, Wajd; Alessi-Severini, Silvia; Leong, Christine

2018-04-04

Drug utilization research on benzodiazepines remains important for measuring trends in consumption within and across borders over time for the sake of monitoring prescribing patterns and identifying potential population safety concerns. The defined daily dose (DDD) system by the World Health Organization (WHO) remains the internationally accepted standard for measuring drug consumption; however, beyond consumption, DDD-based results are difficult to interpret when individual agents are compared with one another or are pooled into a total class-based estimate. The diazepam milligram equivalent (DME) system provides approximate conversions between benzodiazepines and Z-drugs (i.e. zopiclone, zolpidem, zaleplon) based on their pharmacologic potency. Despite this, conversion of total dispensed benzodiazepine quantities into DME values retains diazepam milligrams as the total unit of measurement, which is also impractical for population-level interpretation. In this paper, we propose the use of an integrated DME-DDD metric to obviate the limitations encountered when the component metrics are used in isolation. Through a case example, we demonstrate significant change in results between the DDD and DME-DDD method. Unlike the DDD method, the integrated DME-DDD metric offers estimation of population pharmacologic exposure, and enables superior interpretation of drug utilization results, especially for drug class summary reporting.

A Case Study on the Nature of Informal Conversation in an Organization Utilizing Microblogging Technology

ERIC Educational Resources Information Center

Dembeck, Thomas J.

2013-01-01

The purpose of this case study was to determine the nature of conversations that occur within an organizational microblog and compare them to traditional informal conversations. Since informal conversations are closely associated with reaction to change, this study explored how organizational microblog conversations may be understood to affect…

Electric terminal performance and characterization of solid oxide fuel cells and systems

NASA Astrophysics Data System (ADS)

Lindahl, Peter Allan

Solid Oxide Fuel Cells (SOFCs) are electrochemical devices which can effect efficient, clean, and quiet conversion of chemical to electrical energy. In contrast to conventional electricity generation systems which feature multiple discrete energy conversion processes, SOFCs are direct energy conversion devices. That is, they feature a fully integrated chemical to electrical energy conversion process where the electric load demanded of the cell intrinsically drives the electrochemical reactions and associated processes internal to the cell. As a result, the cell's electric terminals provide a path for interaction between load side electric demand and the conversion side processes. The implication of this is twofold. First, the magnitude and dynamic characteristics of the electric load demanded of the cell can directly impact the long-term efficacy of the cell's chemical to electrical energy conversion. Second, the electric terminal response to dynamic loads can be exploited for monitoring the cell's conversion side processes and used in diagnostic analysis and degradation-mitigating control schemes. This dissertation presents a multi-tier investigation into this electric terminal based performance characterization of SOFCs through the development of novel test systems, analysis techniques and control schemes. First, a reference-based simulation system is introduced. This system scales up the electric terminal performance of a prototype SOFC system, e.g. a single fuel cell, to that of a full power-level stack. This allows realistic stack/load interaction studies while maintaining explicit ability for post-test analysis of the prototype system. Next, a time-domain least squares fitting method for electrochemical impedance spectroscopy (EIS) is developed for reduced-time monitoring of the electrochemical and physicochemical mechanics of the fuel cell through its electric terminals. The utility of the reference-based simulator and the EIS technique are demonstrated through their combined use in the performance testing of a hybrid-source power management (HSPM) system designed to allow in-situ EIS monitoring of a stack under dynamic loading conditions. The results from the latter study suggest that an HSPM controller allows an opportunity for in-situ electric terminal monitoring and control-based mitigation of SOFC degradation. As such, an exploration of control-based SOFC degradation mitigation is presented and ideas for further work are suggested.

Compatibility of Niobium Alloys and Superalloys in a Flowing He-Xe Power Conversion System

NASA Technical Reports Server (NTRS)

Bowman, Cheryl L.; Ritzert, Frank J.; Smialek, James L.; Jaster, Mark L.; rker, Samuel P.

2004-01-01

Proposed concepts for an ambitious mission to explore Jupiter's three icy moons place significant demands on the various spacecraft systems. There are many challenges related to the high output power conversion systems being considered, and one example is the need to ensure system compatibility at all levels. The utilization of appropriate materials for component structures is important to ensuring long mission life. Refractory metal alloys have attractive high-temperature properties in inert environments, but these alloys are sometimes susceptible to contamination. Potential material compatibility issues exist between refractory metal candidates and more conventional alloys. Nb-1Zr has long been considered one of the most well characterized refractory alloys that is well suited for elevated-temperature use and liquid-metal compatibility. However, previous studies have suggested that niobium alloys can not co-exist in a closed system with traditional stainless steels or superalloys due to transport of contaminants. The relevance of this information to a proposed power conversion system is discussed. Also, experiments and fundamental calculations are being performed to determine contamination transport from candidate superalloys to Nb-1Zr in a closed system with an inert carrier gas. Potential protective schemes are explored to ensure system level compatibility between the refractory alloy Nb-1Zr and a nickel-based superalloy.

SP-100 reactor with Brayton conversion for lunar surface applications

NASA Technical Reports Server (NTRS)

Mason, Lee S.; Rodriguez, Carlos D.; Mckissock, Barbara I.; Hanlon, James C.; Mansfield, Brian C.

1992-01-01

Examined here is the potential for integrating Brayton-cycle power conversion with the SP-100 reactor for lunar surface power system applications. Two designs were characterized and modeled. The first design integrates a 100-kWe SP-100 Brayton power system with a lunar lander. This system is intended to meet early lunar mission power needs while minimizing on-site installation requirements. Man-rated radiation protection is provided by an integral multilayer, cylindrical lithium hydride/tungsten (LiH/W) shield encircling the reactor vessel. Design emphasis is on ease of deployment, safety, and reliability, while utilizing relatively near-term technology. The second design combines Brayton conversion with the SP-100 reactor in a erectable 550-kWe powerplant concept intended to satisfy later-phase lunar base power requirements. This system capitalizes on experience gained from operating the initial 100-kWe module and incorporates some technology improvements. For this system, the reactor is emplaced in a lunar regolith excavation to provide man-rated shielding, and the Brayton engines and radiators are mounted on the lunar surface and extend radially from the central reactor. Design emphasis is on performance, safety, long life, and operational flexibility.

A method for evaluating photovoltaic potential in China based on GIS platform

NASA Astrophysics Data System (ADS)

Wang, L. Z.; Tan, H. W.; Ji, L.; Wang, D.

2017-11-01

Solar photovoltaic systems are commonly utilized in China. However, the associated research is still lack of its resource potential analysis in all regions in China. Based on the existed data about solar radiation and system conversion efficiency data, a new method for distributed photovoltaic potential assessment has been presented. The experiment of three kinds of solar photovoltaic system has been set up for the purpose of analyzing the relationship between conversion efficiency and environmental parameters. This paper fits the relationship between conversion efficiency and solar radiation intensity. This method takes into account the amount of solar radiation that is effectively generated and drives away the weak values. With the spatial analysis function of geographic information system (GIS) platform, frequency distribution of solar radiation intensity and PV potential in China can be derived. Furthermore, analytical results show that monocrystalline-silicon PV generation in the north-western and northern areas have reached a level of more than 200 kWh/(m2.a), making those areas be suitable for the development of PV system. However, the potential for southwest areas reaches a level of only 130 kWh/(m2.a). This paper can provide the baseline reference for solar energy development planning.

The utilization of nonterrestrial materials. [resources for solar power satellite construction

NASA Technical Reports Server (NTRS)

1981-01-01

The development of research and technology programs on the user of nonterrestrial materials for space applications was considered with emphasis on the space power satellite system as a model of large space systems for which the use of nonterrestrial materials may be economically viable. Sample topics discussed include the mining of raw materials and the conversion of raw materials into useful products. These topics were considered against a background of the comparative costs of using terrestrial materials. Exploratory activities involved in the preparation of a nonterrestrial materials utilization program, and the human factors involved were also addressed. Several recommendations from the workshop are now incorporated in NASA activities.

Redox Bulk Energy Storage System Study, Volume 1

NASA Technical Reports Server (NTRS)

Ciprios, G.; Erskine, W., Jr.; Grimes, P. G.

1977-01-01

Opportunities were found for electrochemical energy storage devices in the U.S. electric utility industry. Application requirements for these devices were defined, including techno-economic factors. A new device, the Redox storage battery was analyzed. The Redox battery features a decoupling of energy storage and power conversion functions. General computer methods were developed to simulate Redox system operations. These studies showed that the Redox system is potentially attractive if certain performance goals can be achieved. Pathways for reducing the cost of the Redox system were identified.

Genomic and transcriptomic analysis of carbohydrate utilization by Paenibacillus sp. JDR-2: systems for bioprocessing plant polysaccharides

Treesearch

Neha Sawhney; Casey Crooks; Virginia Chow; James F. Preston; Franz St. John

2016-01-01

Background: Polysaccharides comprising plant biomass are potential resources for conversion to fuels and chemicals. These polysaccharides include xylans derived from the hemicellulose of hardwoods and grasses, soluble beta-glucans from cereals and starch as the primary form of energy storage in plants. Paenibacillus sp...

Enhancing biomass utilization for bioenergy-crop rotation systems and alternative conversion processes

USDA-ARS?s Scientific Manuscript database

Biomass for bioenergy has a great deal of potential for decreasing our dependence upon fossil fuels and decreasing the net CO2 accumulation in the atmosphere. Crop residues are often promoted as a means of meeting the total biomass goals to provide sufficient amounts of materials for liquid fuel pro...

International Trade. U.S. Metric Study Interim Report.

ERIC Educational Resources Information Center

Gordon, Gerald F.

In order to evaluate the potential effects of U.S. conversion to SI (Systems International) units on U.S. foreign trade, 188 export product classes and 155 import product classes were selected from 1,166 Standard Industrial Classification (SIC) product classes and questionnaires were mailed to a total of 510 firms, utilizing separate forms for…

The Concept and Experimental Investigation of CO2 and Steam Co-electrolysis for Resource Utilization in Space Exploration

NASA Technical Reports Server (NTRS)

Stoots, Carl; Mulloth, Lila M.; Luna, Bernadette; Varghese, Mini M.

2009-01-01

CO2 acquisition and utilization technologies will have a vital role in determining sustained and affordable life support and in-situ fuel production architectures for human and robotic exploration of Moon and Mars. For long-term human exploration to be practical, reliable technologies have to be implemented to capture and chemically reduce the metabolic CO2 from the cabin air to restitute oxygen consumption. Technologies that facilitate the in-situ capture and conversion of atmospheric CO2 to fuel are essential for a viable human mission to Mars and their demonstration on the moon is critical as well. This paper describes the concept and experimental investigation of a CO2 capture and reduction system that comprises an adsorption compressor and a CO2 and steam co-electrolysis unit. The process products include oxygen for life support and Syngas (CO and H2) for synthetic fuel production. Electrochemical performance in terms of CO2 conversion, oxygen production, and power consumption of a system with a capacity to process 1kg CO2 per day (1-person equivalent) will be discussed.

A Robust Design Approach to Cost Estimation: Solar Energy for Marine Corps Expeditionary Operations

DTIC Science & Technology

2014-07-14

solutions in such areas as photovoltaic arrays for power harvesting, light emitting diodes (LED) for decreased energy consumption, and improved battery...generation and conversion system that allows Marines to power systems with solar energy. Each GREENS is comprised of eight photovoltaic array panels...renewable power sources such as photovoltaic arrays and wind turbines. The HOMER model has been utilized for years by organizations and companies

Power Budget Analysis for High Altitude Airships

NASA Technical Reports Server (NTRS)

Choi, Sang H.; Elliott, James R.; King, Glen C.

2006-01-01

The High Altitude Airship (HAA) has various potential applications and mission scenarios that require onboard energy harvesting and power distribution systems. The energy source considered for the HAA s power budget is solar photon energy that allows the use of either photovoltaic (PV) cells or advanced thermoelectric (ATE) converters. Both PV cells and an ATE system utilizing high performance thermoelectric materials were briefly compared to identify the advantages of ATE for HAA applications in this study. The ATE can generate a higher quantity of harvested energy than PV cells by utilizing the cascaded efficiency of a three-staged ATE in a tandem mode configuration. Assuming that each stage of ATE material has the figure of merit of 5, the cascaded efficiency of a three-staged ATE system approaches the overall conversion efficiency greater than 60%. Based on this estimated efficiency, the configuration of a HAA and the power utility modules are defined.

Investigating the strategies for microbial production of trehalose from lignocellulosic sugars.

PubMed

Wu, Yifei; Wang, Jian; Shen, Xiaolin; Wang, Jia; Chen, Zhenya; Sun, Xinxiao; Yuan, Qipeng; Yan, Yajun

2018-03-01

Trehalose, a multi-functional and value-added disaccharide, can be efficiently biosynthesized from glucose by using a synergetic carbon utilization mechanism (SynCar) which coupled phosphoenolpyruvate (PEP) generation from the second carbon source with PEP-dependent phosphotransferase system (PTS) to promote non-catabolic use of glucose. Considering glucose and xylose present in large amounts in lignocellulosic sugars, we explored new strategies for conversion of both sugars into trehalose. Herein, we first attempted trehalose production from xylose directly, based on which, synergetic utilization of glucose, and xylose prompted by SynCar was implemented in engineered Escherichia coli. As the results, the final titer of trehalose reached 5.55 g/L in shake flask experiments. The conversion ratio or utilization efficiency of glucose or xylose to trehalose was around fourfold higher than that of the original strain (YW-3). This work not only demonstrated the possibility of directly converting xylose (C5 sugar) into trehalose (C12 disaccharide), but also suggested a promising strategy for trehalose production from lignocellulosic sugars for the first time. © 2017 Wiley Periodicals, Inc.

Bacterial production of short-chain organic acids and trehalose from levulinic acid: a potential cellulose-derived building block as a feedstock for microbial production.

PubMed

Habe, Hiroshi; Sato, Shun; Morita, Tomotake; Fukuoka, Tokuma; Kirimura, Kohtaro; Kitamoto, Dai

2015-02-01

Levulinic acid (LA) is a platform chemical derived from cellulosic biomass, and the expansion of LA utilization as a feedstock is important for production of a wide variety of chemicals. To investigate the potential of LA as a substrate for microbial conversion to chemicals, we isolated and identified LA-utilizing bacteria. Among the six isolated strains, Pseudomonas sp. LA18T and Rhodococcus hoagie LA6W degraded up to 70 g/L LA in a high-cell-density system. The maximal accumulation of acetic acid by strain LA18T and propionic acid by strain LA6W was 13.6 g/L and 9.1 g/L, respectively, after a 4-day incubation. Another isolate, Burkholderia stabilis LA20W, produced trehalose extracellularly in the presence of 40 g/L LA to approximately 2 g/L. These abilities to produce useful compounds supported the potential of microbial LA conversion for future development and cellulosic biomass utilization. Copyright © 2014 Elsevier Ltd. All rights reserved.

Electrochemical energy storage systems for solar thermal applications

NASA Technical Reports Server (NTRS)

Krauthamer, S.; Frank, H.

1980-01-01

Existing and advanced electrochemical storage and inversion/conversion systems that may be used with terrestrial solar-thermal power systems are evaluated. The status, cost and performance of existing storage systems are assessed, and the cost, performance, and availability of advanced systems are projected. A prime consideration is the cost of delivered energy from plants utilizing electrochemical storage. Results indicate that the five most attractive electrochemical storage systems are the: iron-chromium redox (NASA LeRC), zinc-bromine (Exxon), sodium-sulfur (Ford), sodium-sulfur (Dow), and zinc-chlorine (EDA).

Extreme Cost Reductions with Multi-Megawatt Centralized Inverter Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schwabe, Ulrich; Fishman, Oleg

2015-03-20

The objective of this project was to fully develop, demonstrate, and commercialize a new type of utility scale PV system. Based on patented technology, this includes the development of a truly centralized inverter system with capacities up to 100MW, and a high voltage, distributed harvesting approach. This system promises to greatly impact both the energy yield from large scale PV systems by reducing losses and increasing yield from mismatched arrays, as well as reduce overall system costs through very cost effective conversion and BOS cost reductions enabled by higher voltage operation.

Parameter study of dual-mode space nuclear fission solid core power and propulsion systems, NUROC3A. AMS report No. 1239c

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, W.W.; Layton, J.P.

1976-09-13

The three-volume report describes a dual-mode nuclear space power and propulsion system concept that employs an advanced solid-core nuclear fission reactor coupled via heat pipes to one of several electric power conversion systems. The NUROC3A systems analysis code was designed to provide the user with performance characteristics of the dual-mode system. Volume 3 describes utilization of the NUROC3A code to produce a detailed parameter study of the system.

Energy conversion of animal manures: Feasibility analysis for thirteen western states

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whittier, J.; Haase, S.; Milward, R.

1993-12-31

The growth and concentration of the livestock industry has led to environmental disposal problems for large quantities of manure at feedlots, dairies, poultry production plants, animal holding areas and pasturelands. Consequently, waste management systems that facilitate energy recovery are becoming increasingly attractive since they address pollution problems and allow for energy generation from manure resources. This paper presents a manure resource assessment for the 13 US Department of Energy, Western Regional Biomass Energy Program states, describes and evaluates available energy conversion technologies, identifies environmental and regulatory factors associated with manure collection, storage and disposal, and identifies common disposal practices specificmore » to animal types and areas within the WRBEP region. The paper also presents a pro forma economic analysis for selected manure-to-energy conversion technologies. The annual energy potential of various manures within the WRBEP region is equivalent to approximately 111 {times} 10{sup 13} Btu. Anaerobic digestion systems, both lagoon and plug flow, offer positive economic returns in a broad range of utility service territories.« less

Fully solar-powered photoelectrochemical conversion for simultaneous energy storage and chemical sensing.

PubMed

Wang, Yongcheng; Tang, Jing; Peng, Zheng; Wang, Yuhang; Jia, Dingsi; Kong, Biao; Elzatahry, Ahmed A; Zhao, Dongyuan; Zheng, Gengfeng

2014-06-11

We report the development of a multifunctional, solar-powered photoelectrochemical (PEC)-pseudocapacitive-sensing material system for simultaneous solar energy conversion, electrochemical energy storage, and chemical detection. The TiO2 nanowire/NiO nanoflakes and the Si nanowire/Pt nanoparticle composites are used as photoanodes and photocathodes, respectively. A stable open-circuit voltage of ∼0.45 V and a high pseudocapacitance of up to ∼455 F g(-1) are obtained, which also exhibit a repeating charging-discharging capability. The PEC-pseudocapacitive device is fully solar powered, without the need of any external power supply. Moreover, this TiO2 nanowire/NiO nanoflake composite photoanode exhibits excellent glucose sensitivity and selectivity. Under the sun light illumination, the PEC photocurrent shows a sensitive increase upon different glucose additions. Meanwhile in the dark, the open-circuit voltage of the charged pseudocapacitor also exhibits a corresponding signal over glucose analyte, thus serving as a full solar-powered energy conversion-storage-utilization system.

Cogeneration Technology Alternatives Study (CTAS). Volume 1: Summary report

NASA Technical Reports Server (NTRS)

Gerlaugh, H. E.; Hall, E. W.; Brown, D. H.; Priestley, R. R.; Knightly, W. F.

1980-01-01

Large savings can be made in industry by cogenerating electric power and process heat in single energy conversion systems rather than separately in utility plants and in process boilers. About fifty industrial processes from the largest energy consuming sectors were used as a basis for matching a similar number of energy conversion systems that are considered as candidates which can be made available by the 1985 to 2000 time period. The sectors considered included food, textiles, lumber, paper, chemicals, petroleum, glass, and primary metals. The energy conversion systems included steam and gas turbines, diesels, thermionics, stirling, closed-cycle and steam injected gas turbines, and fuel cells. Fuels considered were coal, both coal and petroleum-based residual and distillate liquid fuels, and low Btu gas obtained through the on-site gasification of coal. An attempt was made to use consistent assumptions and a consistent set of ground rules for determining performance and cost in individual plants and on a national level. It was found that: (1) atmospheric and pressurized fluidized bed steam turbine systems were the most attractive of the direct coal-fired systems; and (2) open-cycle gas turbines with heat recovery steam generators and combined-cycles with NO(x) emission reduction and moderately increased firing temperatures were the most attractive of the coal-derived liquid-fired systems.

Design of a photovoltaic system for a southeast all-electric residence

NASA Astrophysics Data System (ADS)

Mehalick, E. M.; Tully, G. F.; Johnson, J.; Truncellito, N.; Schaeffer, R.; Parker, J.

1982-01-01

A photovoltaic system was developed and integrated into a single-story residence suitable for the Southeast region of the country. The design addresses an integral mounted array which displaces conventional roof sheathing, roofing felt and shingles. The array has a rated power output of 5.6 kW and covers 86 sq.m. of roof area. A 6 kW utility-tied inverter is used in the power conversion subsystem, representative of a lower cost version, currently available hardware. The system provides feedback of excess energy to the utility, which is the most promising approach for grid-connected systems in the mid-1980's. The complete system and house design are described, including all the pertinent installation and construction drawings. Specific performance results are presented for the Miami, Florida, and Charleston, SC, regions.

Phase 1 of the First Small Power System Experiment (engineering Experiment No. 1). Volume 5: Supporting Analyses and Trade Studies. [development and testing of a solar thermal power plant

NASA Technical Reports Server (NTRS)

Holl, R. J.

1979-01-01

The development and design of a modular solar thermal power system for application in the 1 to 10 MWe range is described. The system is used in remote utility applications, small communities, rural areas, and for industrial uses. Thermal and stress analyses are performed on the collector subsystem, energy storage subsystem, energy transport subsystem, the power conversion subsystem, and the plant control subsystem.

Construction of a 1 MeV Electron Accelerator for High Precision Beta Decay Studies

NASA Astrophysics Data System (ADS)

Longfellow, Brenden

2014-09-01

Beta decay energy calibration for detectors is typically established using conversion sources. However, the calibration points from conversion sources are not evenly distributed over the beta energy spectrum and the foil backing of the conversion sources produces perturbations in the calibration spectrum. To improve this, an external, tunable electron beam coupled by a magnetic field can be used to calibrate the detector. The 1 MeV electron accelerator in development at Triangle Universities Nuclear Laboratory (TUNL) utilizes a pelletron charging system. The electron gun shoots 104 electrons per second with an energy range of 50 keV to 1 MeV and is pulsed at a 10 kHz rate with a few ns width. The magnetic field in the spectrometer is 1 T and guiding fields of 0.01 to 0.05 T for the electron gun are used to produce a range of pitch angles. This accelerator can be used to calibrate detectors evenly over its energy range and determine the detector response over a range of pitch angles. Beta decay energy calibration for detectors is typically established using conversion sources. However, the calibration points from conversion sources are not evenly distributed over the beta energy spectrum and the foil backing of the conversion sources produces perturbations in the calibration spectrum. To improve this, an external, tunable electron beam coupled by a magnetic field can be used to calibrate the detector. The 1 MeV electron accelerator in development at Triangle Universities Nuclear Laboratory (TUNL) utilizes a pelletron charging system. The electron gun shoots 104 electrons per second with an energy range of 50 keV to 1 MeV and is pulsed at a 10 kHz rate with a few ns width. The magnetic field in the spectrometer is 1 T and guiding fields of 0.01 to 0.05 T for the electron gun are used to produce a range of pitch angles. This accelerator can be used to calibrate detectors evenly over its energy range and determine the detector response over a range of pitch angles. TUNL REU Program.

Container System Hardware Status Report

DTIC Science & Technology

1986-01-01

includes the proureentofeight SL-7 class high - speed containerships and their Subsequent conversion to a cargo configuration specifically designed for...wide, 53.5-in high , 242-in long, and Weighs 4,000 lbs. The MILVAN chassis were competitively procured from incustry utilizing a performance military...accept load transfer from a cargo ship and equipped with a ramp for Roll On/Roll Off (RO/RO) discharge systems. The LAMP-H will :1replace the LARC-LX

Modeling and Design Optimization of Multifunctional Membrane Reactors for Direct Methane Aromatization

PubMed Central

Fouty, Nicholas J.; Carrasco, Juan C.; Lima, Fernando V.

2017-01-01

Due to the recent increase of natural gas production in the U.S., utilizing natural gas for higher-value chemicals has become imperative. Direct methane aromatization (DMA) is a promising process used to convert methane to benzene, but it is limited by low conversion of methane and rapid catalyst deactivation by coking. Past work has shown that membrane separation of the hydrogen produced in the DMA reactions can dramatically increase the methane conversion by shifting the equilibrium toward the products, but it also increases coke production. Oxygen introduction into the system has been shown to inhibit this coke production while not inhibiting the benzene production. This paper introduces a novel mathematical model and design to employ both methods in a multifunctional membrane reactor to push the DMA process into further viability. Multifunctional membrane reactors, in this case, are reactors where two different separations occur using two differently selective membranes, on which no systems studies have been found. The proposed multifunctional membrane design incorporates a hydrogen-selective membrane on the outer wall of the reaction zone, and an inner tube filled with airflow surrounded by an oxygen-selective membrane in the middle of the reactor. The design is shown to increase conversion via hydrogen removal by around 100%, and decrease coke production via oxygen addition by 10% when compared to a tubular reactor without any membranes. Optimization studies are performed to determine the best reactor design based on methane conversion, along with coke and benzene production. The obtained optimal design considers a small reactor (length = 25 cm, diameter of reaction tube = 0.7 cm) to subvert coke production and consumption of the product benzene as well as a high permeance (0.01 mol/s·m2·atm1/4) through the hydrogen-permeable membrane. This modeling and design approach sets the stage for guiding further development of multifunctional membrane reactor models and designs for natural gas utilization and other chemical reaction systems. PMID:28850068

Teaching and Learning Foreign Languages via System of "Voice over Internet Protocol" and Language Interactions Case Study: Skype

ERIC Educational Resources Information Center

Wahid, Wazira Ali Abdul; Ahmed, Eqbal Sulaiman; Wahid, Muntaha Ali Abdul

2015-01-01

This issue expresses a research study based on the online interactions of English teaching specially conversation through utilizing VOIP (Voice over Internet Protocol) and cosmopolitan online theme. Data has been achieved by interviews. Simplifiers indicate how oral tasks require to be planned upon to facilitate engagement models propitious to…

The Use of Modular Computer-Based Lessons in a Modification of the Classical Introductory Course in Organic Chemistry.

ERIC Educational Resources Information Center

Stotter, Philip L.; Culp, George H.

An experimental course in organic chemistry utilized computer-assisted instructional (CAI) techniques. The CAI lessons provided tutorial drill and practice and simulated experiments and reactions. The Conversational Language for Instruction and Computing was used, along with a CDC 6400-6600 system; students scheduled and completed the lessons at…

New Wind in Old Sails: Novel Applications of Triphos-based Transition Metal Complexes as Homogeneous Catalysts for Small Molecules and Renewables Activation.

PubMed

Mellone, Irene; Bertini, Federica; Gonsalvi, Luca; Guerriero, Antonella; Peruzzini, Maurizio

2015-01-01

Recent developments in the coordination chemistry and applications of Ru-triphos [triphos = 1,1,1-tris-(diphenylphosphinomethyl)ethane] systems are reviewed, highlighting their role as active and selective homogenous catalysts for small molecule activation, biomass conversions and in carbon dioxide utilization-related processes.

Coal conversion products Industrial applications

NASA Technical Reports Server (NTRS)

Warren, D.; Dunkin, J.

1980-01-01

The synfuels economic evaluation model was utilized to analyze cost and product economics of the TVA coal conversion facilities. It is concluded that; (1) moderate yearly future escalations ( 6%) in current natural gas prices will result in medium-Btu gas becoming competitive with natural gas at the plant boundary; (2) utilizing DRI price projections, the alternate synfuel products, except for electricity, will be competitive with their counterparts; (3) central site fuel cell generation of electricity, utilizing MBG, is economically less attractive than the other synthetic fuels, given projected price rises in electricity produced by other means; and (4) because of estimated northern Alabama synfuels market demands, existing conventional fuels, infrastructure and industrial synfuels retrofit problems, a diversity of transportable synfuels products should be produced by the conversion facility.

A summary of the status of biomass conversion technologies and opportunities for their use in developing countries

NASA Astrophysics Data System (ADS)

Waddle, D. B.; Perlack, R. D.; Wimberly, J.

Biomass plays a significant role in energy use in developing countries: however, these resources are often used very inefficiently. Recent technology developments have made possible improved conversion efficiencies for utility scale technologies. These developments may be of interest in the wake of recent policy changes occurring in several developing countries, with respect to independent power production. Efforts are also being directed at developing biomass conversion technologies that can interface and/or compete with internal combustion engines for small, isolated loads. The technological status is reviewed of biomass conversion technologies appropriate for commercial, industrial, and small utility applications in developing countries. Market opportunities, constraints, and technology developments are also discussed.

Biomass energy production. Citations from the International Aerospace Abstracts data base

NASA Technical Reports Server (NTRS)

Moore, P. W.

1980-01-01

These 210 citations from the international literature describe the production and/or utilization of most forms of biomass as a source of energy, fuel, food, and chemical intermediates or feedstocks. Biomass conversion by incineration, gasification, pyrolysis, hydrolysis, anaerobic digestion, or fermentation, as well as by catalytic, photosynthetic, chemosynthetic, and bio-electrochemical means are among the conversion processes considered. Discussions include biomass plantation and material productivity, transportation and equipment requirements, effects, comparisons of means and efficiencies of utilization and conversion, assessments of limitations, and evaluations of economic potential.

Thermochemical recovery of heat contained in flue gases by means of bioethanol conversion

NASA Astrophysics Data System (ADS)

Pashchenko, D. I.

2013-06-01

In the present paper consideration is being given to the use of bioethanol in the schemes of thermochemical recovery of heat contained in exit flue gases. Schematic diagrams illustrate the realization of thermochemical heat recovery by implementing ethanol steam conversion and conversion of ethanol by means of products of its complete combustion. The feasibility of attaining a high degree of recovery of heat contained in flue gases at the moderate temperature (up to 450°C) of combustion components is demonstrated in the example of the energy balance of the system for thermochemical heat recovery. The simplified thermodynamic analysis of the process of ethanol steam conversion was carried out in order to determine possible ranges of variation of process variables (temperature, pressure, composition) of a reaction mixture providing the efficient heat utilization. It was found that at the temperature above 600 K the degree of ethanol conversion is near unity. The equilibrium composition of products of reaction of ethanol steam conversion has been identified for different temperatures at which the process occurs at the ratio H2O/EtOH = 1 and at the pressure of 0.1 MPa. The obtained results of calculation agree well with the experimental data.

Wind power for the electric-utility industry: Policy incentives for fuel conservation

NASA Astrophysics Data System (ADS)

March, F.; Dlott, E. H.; Korn, D. H.; Madio, F. R.; McArthur, R. C.; Vachon, W. A.

1982-06-01

A systematic method for evaluating the economics of solar-electric/conservation technologies as fuel-savings investments for electric utilities in the presence of changing federal incentive policies is presented. The focus is on wind energy conversion systems (WECS) as the solar technology closest to near-term large scale implementation. Commercially available large WECS are described, along with computer models to calculate the economic impact of the inclusion of WECS as 10% of the base-load generating capacity on a grid. A guide to legal structures and relationships which impinge on large-scale WECS utilization is developed, together with a quantitative examination of the installation of 1000 MWe of WECS capacity by a utility in the northeast states. Engineering and financial analyses were performed, with results indicating government policy changes necessary to encourage the entrance of utilities into the field of windpower utilization.

Conversion of stranded waste-stream carbon and nutrients into value-added products via metabolically coupled binary heterotroph-photoautotroph system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bohutskyi, Pavlo; Kucek, Leo A.; Hill, Eric

Metabolic flexibility and robustness of phototroph- heterotroph co-cultures provide a flexible binary engineering platform for a variety of biotechnological and environmental applications. Here, we metabolically coupled a heterotrophic bacterium Bacillus subtilis with astaxanthin producing alga Haematococcus pluvialis and successfully applied this binary co-culture for conversion of the starch-rich waste stream into valuable astaxanthin-rich biomass. Importantly, the implemented system required less mass transfer of CO2 and O2 due to in-situ exchange between heterotroph and phototroph, which can contribute to reduction in energy consumption for wastewater treatment. In addition, the maximum reduction in chemical oxygen demand, total nitrogen and phosphorus reached 65%,more » 55% and 30%, respectively. The preliminary economic analysis indicated that realization of produced biomass with 0.8% astaxanthin content may generate annual revenues of $3.2M (baseline scenario) from treatment of wastewater (1,090 m3/day) from a potato processing plant. Moreover, the revenues may be increased up to $18.2M for optimized scenario with astaxanthin content in algae of 2%. This work demonstrates a successful proof-of-principle for conversion of waste carbon and nutrients into targeted value-added products through metabolic connection of heterotrophic and phototrophic organisms. Utilization of heterotrophic-algal binary cultures opens new perspectives for designing highly-efficient production processes for feedstock biomass production as well as allows utilization of variety of organic agricultural, chemical, or municipal wastes.« less

Magnetic Field Experiment Data Analysis System

NASA Technical Reports Server (NTRS)

Holland, D. B.; Zanetti, L. J.; Suther, L. L.; Potemra, T. A.; Anderson, B. J.

1995-01-01

The Johns Hopkins University Applied Physics Laboratory (JHU/APL) Magnetic Field Experiment Data Analysis System (MFEDAS) has been developed to process and analyze satellite magnetic field experiment data from the TRIAD, MAGSAT, AMPTE/CCE, Viking, Polar BEAR, DMSP, HILAT, UARS, and Freja satellites. The MFEDAS provides extensive data management and analysis capabilities. The system is based on standard data structures and a standard user interface. The MFEDAS has two major elements: (1) a set of satellite unique telemetry processing programs for uniform and rapid conversion of the raw data to a standard format and (2) the program Magplot which has file handling, data analysis, and data display sections. This system is an example of software reuse, allowing new data sets and software extensions to be added in a cost effective and timely manner. Future additions to the system will include the addition of standard format file import routines, modification of the display routines to use a commercial graphics package based on X-Window protocols, and a generic utility for telemetry data access and conversion.

Utilization of methanol for polymer electrolyte fuel cells in mobile systems

NASA Astrophysics Data System (ADS)

Schmidt, V. M.; Brockerhoff, P.; Hohlein, B.; Menzer, R.; Stimming, U.

1994-04-01

The constantly growing volume of road traffic requires the introduction of new vehicle propulsion systems with higher efficiency and drastically reduced emission rates. As part of the fuel cell programme of the Research Centre Julich a vehicle propulsion system with methanol as secondary energy carrier and a polymer electrolyte membrane fuel cell (PEMFC) as the main component for energy conversion is developed. The fuel gas is produced by a heterogeneously catalyzed steam reforming reaction in which methanol is converted to H2, CO and CO2. The required energy is provided by the catalytic conversion of methanol for both heating up the system and reforming methanol. The high CO content of the fuel gas requires further processing of the gas or the development of new electrocatalysts for the anode. Various Pt-Ru alloys show promising behaviour as CO-tolerant anodes. The entire fuel cell system is discussed in terms of energy and emission balances. The development of important components is described and experimental results are discussed.

Bi-directional four quadrant (BDQ4) power converter development

NASA Technical Reports Server (NTRS)

Schwarz, F. C.

1979-01-01

The feasibility for implementation of a concept for direct ac/dc multikilowatt power conversion with bidirectional transfer of energy was investigated. A 10 kHz current carrier was derived directly from a common 60 Hz three phase power system. This carrier was modulated to remove the 360 Hz ripple, inherent in the three phase power supply and then demodulated and processed by a high frequency filter. The resulting dc power was then supplied to a load. The process was implemented without the use of low frequency transformers and filters. This power conversion processes was reversible and can operate in the four quadrants as viewed from any of the two of the converter's ports. Areas of application include: power systems on air and spacecraft; terrestrial traction; integration of solar and wind powered systems with utility networks; HVDC; asynchronous coupling of polyphase networks; heat treatment; industrial machine drives; and power supplies for any use including instrumentation.

Analysis to develop a program for energy-integrated farm systems

NASA Astrophysics Data System (ADS)

Eakin, D. E.; Clark, M. A.; Inaba, L. K.; Johnson, K. I.

1981-09-01

A program to use renewable energy resources and possibly develop decentralization of energy systems for agriculture is discussed. The program's objective is determined by: (1) an analysis of the technologies that could be utilized to transform renewable farm resources to energy by the year 2000, (2) the quantity of renewable farm resources that are available, and (3) current energy-use patterns. Individual research, development, and demonstration projects are fit into a national program of energy-integrated farm systems on the basis of market need, conversion potential, technological opportunities, and acceptability. Quantification of these factors for the purpose of establishing program guidelines is conducted using the following four precepts: (1) market need is identified by current use of energy for agricultural production; (2) conversion potential is determined by the availability of renewable resources; and (3) technological opportunities are determined by the state-of-the-art methods, techniques, and processes that can convert renewable resources into farm energy.

Using optimal control methods with constraints to generate singlet states in NMR

NASA Astrophysics Data System (ADS)

Rodin, Bogdan A.; Kiryutin, Alexey S.; Yurkovskaya, Alexandra V.; Ivanov, Konstantin L.; Yamamoto, Satoru; Sato, Kazunobu; Takui, Takeji

2018-06-01

A method is proposed for optimizing the performance of the APSOC (Adiabatic-Passage Spin Order Conversion) technique, which can be exploited in NMR experiments with singlet spin states. In this technique magnetization-to-singlet conversion (and singlet-to-magnetization conversion) is performed by using adiabatically ramped RF-fields. Optimization utilizes the GRAPE (Gradient Ascent Pulse Engineering) approach, in which for a fixed search area we assume monotonicity to the envelope of the RF-field. Such an approach allows one to achieve much better performance for APSOC; consequently, the efficiency of magnetization-to-singlet conversion is greatly improved as compared to simple model RF-ramps, e.g., linear ramps. We also demonstrate that the optimization method is reasonably robust to possible inaccuracies in determining NMR parameters of the spin system under study and also in setting the RF-field parameters. The present approach can be exploited in other NMR and EPR applications using adiabatic switching of spin Hamiltonians.

Engineered microbial systems for enhanced conversion of lignocellulosic biomass.

PubMed

Elkins, James G; Raman, Babu; Keller, Martin

2010-10-01

In order for plant biomass to become a viable feedstock for meeting the future demand for liquid fuels, efficient and cost-effective processes must exist to breakdown cellulosic materials into their primary components. A one-pot conversion strategy or, consolidated bioprocessing, of biomass into ethanol would provide the most cost-effective route to renewable fuels and the realization of this technology is being actively pursued by both multi-disciplinary research centers and industrialists working at the very cutting edge of the field. Although a diverse range of bacteria and fungi possess the enzymatic machinery capable of hydrolyzing plant-derived polymers, none discovered so far meet the requirements for an industrial strength biocatalyst for the direct conversion of biomass to combustible fuels. Synthetic biology combined with a better fundamental understanding of enzymatic cellulose hydrolysis at the molecular level is enabling the rational engineering of microorganisms for utilizing cellulosic materials with simultaneous conversion to fuel. Copyright © 2010 Elsevier Ltd. All rights reserved.

Comparison of Stirling engines for use with a 25-kW disk-electric conversion system

NASA Technical Reports Server (NTRS)

Shaltens, Richard K.

1987-01-01

Heat engines were evaluated for terrestrial solar heat receivers. The Stirling Engine was identified as one of the most promising engines for terrestrial applications. The potential to meet the Department of Energy (DOE) goals for performance and cost can be met by the free-piston Stirling engine. NASA Lewis is providing technical management for an Advanced Stirling Conversion System (ASCS) through a cooperative interagency agreement with DOE. Parallel contracts were awarded for conceptual designs of an ASCS. Each design will feature a free-piston Stirling engine, a liquid-metal heat pipe receiver, and a means to provide about 25 kW of electric power to a utility grid while meeting long-term performance and goals. The Mechanical Technology, Ins. (MTI) design incorporates a linear alternator to directly convert the solar energy to electricity while the Stirling Technology Company (STC) generates electrical power indirectly by using a hydraulic output to a ground-bases hydraulic pump/motor coupled to a rotating alternator. Both designs use technology which can reasonably be expected to be available in the 1980's. The ASCS designs using a free-piston Stirling engine, a heat transport system, a receiver, and the methods of providing electricity to the utility grid will be discussed.

Nucleic acids, compositions and uses thereof

DOEpatents

Preston, III, James F.; Chow, Virginia [Gainesville, FL; Nong, Guang [Gainesville, FL; Rice, John D [Gainesville, FL; John, Franz J [Baltimore, MD

2012-02-21

The subject invention provides at least one nucleic acid sequence encoding an aldouronate-utilization regulon isolated from Paenibacillus sp. strain JDR-2, a bacterium which efficiently utilizes xylan and metabolizes aldouronates (methylglucuronoxylosaccharides). The subject invention also provides a means for providing a coordinately regulated process in which xylan depolymerization and product assimilation are coupled in Paenibacillus sp. strain JDR-2 to provide a favorable system for the conversion of lignocellulosic biomass to biobased products. Additionally, the nucleic acid sequences encoding the aldouronate-utilization regulon can be used to transform other bacteria to form organisms capable of producing a desired product (e.g., ethanol, 1-butanol, acetoin, 2,3-butanediol, 1,3-propanediol, succinate, lactate, acetate, malate or alanine) from lignocellulosic biomass.

Combating Terrorism Technical Support Office. 2008 Review

DTIC Science & Technology

2009-01-15

threat object displayed at the operator control unit of the robotic platform. Remote Utility Conversion Kit The Remote Utility Conversion Kit (RUCK) is a...three- dimensional and isometric simulations and games. Develop crowd models, adversarial behavior models, network-based simulations, mini-simulations...Craft-Littoral The modular unmanned surface craft-littoral ( MUSCL ) is a spin- off of EOD/LIC’s Unmanned Reconnaissance Observation Craft, developed

Comparative Evaluation of Phase 1 Results from the Energy Conversion Alternatives Study (ECAS). [coal utilization for electric power plants feasibility analysis

NASA Technical Reports Server (NTRS)

1976-01-01

Ten advanced energy conversion systems for central-station, based-load electric power generation using coal and coal-derived fuels which were studied by NASA are presented. Various contractors were selected by competitive bidding to study these systems. A comparative evaluation is provided of the contractor results on both a system-by-system and an overall basis. Ground rules specified by NASA, such as coal specifications, fuel costs, labor costs, method of cost comparison, escalation and interest during construction, fixed charges, emission standards, and environmental conditions, are presented. Each system discussion includes the potential advantages of the system, the scope of each contractor's analysis, typical schematics of systems, comparison of cost of electricity and efficiency for each contractor, identification and reconciliation of differences, identification of future improvements, and discussion of outside comments. Considerations common to all systems, such as materials and furnaces, are also discussed. Results of selected in-house analyses are presented, in addition to contractor data. The results for all systems are then compared.

Roles of free radicals in NO oxidation by Fenton system and the enhancement on NO oxidation and H2O2 utilization efficiency.

PubMed

Zhao, Haiqian; Dong, Ming; Wang, Zhonghua; Wang, Huaiyuan; Qi, Hanbing

2018-06-20

Low H 2 O 2 utilization efficiency is the main problem when Fenton system was used to oxidize NO in flue gas. To understand the behavior of the free radicals during NO oxidation process in Fenton system is crucial to solving this problem. The oxidation capacity of ·OH and HO 2 · on NO in Fenton system was compared and the useless consumption path of ·OH and HO 2 · that caused the low utilization efficiency of H 2 O 2 were studied. A method to enhance the oxidation ability and H 2 O 2 utilization efficiency by adding reducing additives in Fenton system was proposed. The results showed that both of ·OH and HO 2 · were active substances that oxidize NO. However, the oxidation ability of ·OH radicals was stronger. The vast majority of ·OH and HO 2 · was consumed by rapid reaction ·OH+HO 2 ·→H 2 O+O 2 , which was the primary reason for the low utilization efficiency of H 2 O 2 in Fenton system. Hydroxylamine hydrochloride and ascorbic acid could accelerate the conversion of Fe 3+ to Fe 2+ , thereby increase the generation rate of ·OH and decrease the generation rate of HO 2 ·. As a result, the oxidation ability and H 2 O 2 utilization efficiency were enhanced.

The reciprocity law concerning light dose relationships applied to BisGMA/TEGDMA photopolymers: theoretical analysis and experimental characterization.

PubMed

Wydra, James W; Cramer, Neil B; Stansbury, Jeffrey W; Bowman, Christopher N

2014-06-01

A model BisGMA/TEGDMA unfilled resin was utilized to investigate the effect of varied irradiation intensity on the photopolymerization kinetics and shrinkage stress evolution, as a means for evaluation of the reciprocity relationship. Functional group conversion was determined by FTIR spectroscopy and polymerization shrinkage stress was obtained by a tensometer. Samples were polymerized with UV light from an EXFO Acticure with 0.1wt% photoinitiator. A one-dimensional kinetic model was utilized to predict the conversion-dose relationship. As irradiation intensity increased, conversion decreased at a constant irradiation dose and the overall dose required to achieve full conversion increased. Methacrylate conversion ranged from 64±2% at 3mW/cm(2) to 78±1% at 24mW/cm(2) while the final shrinkage stress varied from 2.4±0.1MPa to 3.0±0.1MPa. The ultimate conversion and shrinkage stress levels achieved were dependent not only upon dose but also the irradiation intensity, in contrast to an idealized reciprocity relationship. A kinetic model was utilized to analyze this behavior and provide theoretical conversion profiles versus irradiation time and dose. Analysis of the experimental and modeling results demonstrated that the polymerization kinetics do not and should not be expected to follow the reciprocity law behavior. As irradiation intensity is increased, the overall dose required to achieve full conversion also increased. Further, the ultimate conversion and shrinkage stress that are achieved are not dependent only upon dose but rather upon the irradiation intensity and corresponding polymerization rate. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Extracellular lignase: a key to enhanced cellulose utilization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hira, A.; Barnett, S.M.; Shieh, C.H.

1978-01-01

An alternate approach to the conventional chemical processing of lignin, a potential renewable resource, is enzymic conversion. Biodegradation of wood, a lignin-cellulose complex, is accomplished naturally by various enzymes of microbial origin. Extracellular lignases have been isolated from pure cultures of Polyporus versicolor, Phanerochaete chrysosporium, and Pleurotus ostreatus. The isolated enzyme systems from these organisms have shown substrate specificity for guaiacol and hydroquinone and yielded a positive syringaldazine test. A commercial lignin was degraded by the enzyme system.

Catalysts and process for liquid hydrocarbon fuel production

DOEpatents

White, Mark G.; Ranaweera, Samantha A.; Henry, William P.

2016-08-02

The present invention provides a novel process and system in which a mixture of carbon monoxide and hydrogen synthesis gas, or syngas, is converted into hydrocarbon mixtures composed of high quality distillates, gasoline components, and lower molecular weight gaseous olefins in one reactor or step. The invention utilizes a novel supported bimetallic ion complex catalyst for conversion, and provides methods of preparing such novel catalysts and use of the novel catalysts in the process and system of the invention.

A summary of the status of biomass conversion technologies and opportunities for their use in Latin America

NASA Astrophysics Data System (ADS)

Waddle, D. B.; Perlack, R. D.

1990-03-01

Biomass plays a significant role in energy use in developing countries; however, these resources are often used very inefficiently. Recent technology developments have made possible improved conversion efficiencies for utility scale technologies. These developments may be of interest in the wake of recent policy changes occurring in Central America, with respect to independent power production. Efforts are also being directed at developing biomass conversion technologies that can interface and/or compete with internal combustion engines for small, isolated loads. This paper reviews the technological status of biomass conversion technologies appropriate for commercial, industrial, and small utility applications in developing countries, and in Latin America in particular. Market opportunities, constraints, and technology developments are also discussed.

Intra-Operative Predictors of difficult cholecystectomy and Conversion to Open Cholecystectomy - A New Scoring System.

PubMed

Ahmed, Nauman; Hassan, Maaz Ul; Tahira, Maham; Samad, Abdul; Rana, Hamad Naeem

2018-01-01

To evaluate the intra-operative scoring system to predict difficult cholecystectomy and conversion to open surgery. This descriptive study was conducted from March 2016 to August, 2016 in the Department of Surgery, Shalimar Hospital. The study recruited 120 patients of either gender, age greater than 18 years and indicated for laparoscopic cholecystectomy (LC). Intra-operatively all patients were evaluated using the new scoring system. The scoring system included five aspects; appearance and adhesion of Gall Bladder (GB), distension or contracture degree of GB, ease in access, local or septic complications, and time required for cystic artery and duct identification. The scoring system ranges from 0 to 10, classified as score of <2 being considered easy, 2 to 4 moderate, 5-7 very difficult, and 8 to 10, extreme. Patient demographic data (i.e. age, gender), co-morbidities, intra-operative scores using the scoring system and conversion to open were recorded. The data was analysed using statistical analysis software SPSS (IBM). Among one hundred and twenty participants, sixty seven percent were females and the mean age (years) was 43.05 ± 14.16. Co-morbidities were present in twenty percent patients with eleven diagnosed with diabetes, six with hypertension and five with both hypertension and diabetes. The conversion rate to open surgery was 6.7%. The overall mean intra-operative scores were 3.52 ± 2.23; however significant difference was seen in mean operative score of converted to open and those not converted to open (8.00 ± 0.92 Vs. 3.20 V 1.92; p-value = 0.001). Among eight cases converted to open, three (37.5%) were in very difficult category while five (62.5%) were in extreme category. Moreover, age greater than 40 years and being diabetic were also the risk factors for conversion to open surgery. The new intra-operative scoring system is a valuable assessment tool to predict difficult laparoscopic cholecystectomy and conversion parameters to open surgery and its utility could improve patient's clinical outcome indicated for laparoscopic cholecystectomy.

An Integrated Management Support and Production Control System for Hardwood Forest Products

Treesearch

Guillermo A. Mendoza; Roger J. Meimban; William Sprouse; William G. Luppold; Philip A. Araman

1991-01-01

Spreadsheet and simulation models are tools which enable users to analyze a large number of variables affecting hardwood material utilization and profit in a systematic fashion. This paper describes two spreadsheet models; SEASaw and SEAIn, and a hardwood sawmill simulator. SEASaw is designed to estimate the amount of conversion from timber to lumber, while SEAIn is a...

Investigations of Nitrogen Oxide Plasmas: Fundamental Chemistry and Surface Reactivity and Monitoring Student Perceptions in a General Chemistry Recitation

ERIC Educational Resources Information Center

Blechle, Joshua M.

2016-01-01

Part I of this dissertation focuses on investigations of nitrogen oxide plasma systems. With increasing concerns over the environmental presence of NxOy species, there is growing interest in utilizing plasma-assisted conversion techniques. Advances, however, have been limited because of the lack of knowledge regarding the fundamental chemistry of…

OXIDATION OF ALKANES WITH AIR USING IRON AND MANGANESE CATALYSTS. AN OVERALL GREEN CHEMISTRY APPROACH INCLUDING THE USE OF ALTERNATIVE SOLVENT SYSTEMS GENERATED BY PARIS II

EPA Science Inventory

The selective oxidation of alkanes is an industrially important process that is often plagued by low conversions and the formation of unwanted by-products. Research being conducted at the USEPA, implements a Green chemistry approach which is utilized to improve these difficult o...

Highly efficient reversible addition-fragmentation chain-transfer polymerization in ethanol/water via flow chemistry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ye, Piaoran; Cao, Peng -Fei; Su, Zhe

Here, utilization of a flow reactor under high pressure allows highly efficient polymer synthesis via reversible addition–fragmentation chain-transfer (RAFT) polymerization in an aqueous system. Compared with the batch reaction, the flow reactor allows the RAFT polymerization to be performed in a high-efficiency manner at the same temperature. The adjustable pressure of the system allows further elevation of the reaction temperature and hence faster polymerization. Other reaction parameters, such as flow rate and initiator concentration, were also well studied to tune the monomer conversion and the molar mass dispersity (Ð) of the obtained polymers. Gel permeation chromatography, nuclear magnetic resonance (NMR),more » and Fourier transform infrared spectroscopies (FTIR) were utilized to monitor the polymerization process. With the initiator concentration of 0.15 mmol L –1, polymerization of poly(ethylene glycol) methyl ethermethacrylate with monomer conversion of 52% at 100 °C under 73 bar can be achieved within 40 min with narrow molar mass dispersity (D) Ð (<1.25). The strategy developed here provides a method to produce well-defined polymers via RAFT polymerization with high efficiency in a continuous manner.« less

Mars Atmospheric Conversion to Methane and Water: An Engineering Model of the Sabatier Reactor with Characterization of Ru/Al2O3 for Long Duration Use on Mars

NASA Technical Reports Server (NTRS)

Meier, Anne J.; Shah, Malay; Petersen, Elspeth; Hintze, Paul; Muscatello, Tony

2017-01-01

The Atmospheric Processing Module (APM) is a Mars In-Situ Resource Utilization (ISRU) technology designed to demonstrate conversion of the Martian atmosphere into methane and water. The Martian atmosphere consists of approximately 95 carbon dioxide (CO2) and residual argon and nitrogen. APM utilizes cryocoolers for CO2 acquisition from a simulated Martian atmosphere and pressure. The captured CO2 is sublimated and pressurized as a feedstock into the Sabatier reactor, which converts CO2 and hydrogen to methane and water. The Sabatier reaction occurs over a packed bed reactor filled with Ru/Al2O3 pellets. The long duration use of the APM system and catalyst was investigated for future scaling and failure limits. Failure of the catalyst was detected by gas chromatography and temperature sensors on the system. Following this, characterization and experimentation with the catalyst was carried out with analysis including x-ray photoelectron spectroscopy and scanning electron microscopy with elemental dispersive spectroscopy. This paper will discuss results of the catalyst performance, the overall APM Sabatier approach, as well as intrinsic catalyst considerations of the Sabatier reactor performance incorporated into a chemical model.

Near-infrared light controlled photocatalytic activity of carbon quantum dots for highly selective oxidation reaction

NASA Astrophysics Data System (ADS)

Li, Haitao; Liu, Ruihua; Lian, Suoyuan; Liu, Yang; Huang, Hui; Kang, Zhenhui

2013-03-01

Selective oxidation of alcohols is a fundamental and significant transformation for the large-scale production of fine chemicals, UV and visible light driven photocatalytic systems for alcohol oxidation have been developed, however, the long wavelength near infrared (NIR) and infrared (IR) light have not yet fully utilized by the present photocatalytic systems. Herein, we reported carbon quantum dots (CQDs) can function as an effective near infrared (NIR) light driven photocatalyst for the selective oxidation of benzyl alcohol to benzaldehyde. Based on the NIR light driven photo-induced electron transfer property and its photocatalytic activity for H2O2 decomposition, this metal-free catalyst could realize the transformation from benzyl alcohol to benzaldehyde with high selectivity (100%) and conversion (92%) under NIR light irradiation. HO&z.rad; is the main active oxygen specie in benzyl alcohol selective oxidative reaction confirmed by terephthalic acid photoluminescence probing assay (TA-PL), selecting toluene as the substrate. Such metal-free photocatalytic system also selectively converts other alcohol substrates to their corresponding aldehydes with high conversion, demonstrating a potential application of accessing traditional alcohol oxidation chemistry.Selective oxidation of alcohols is a fundamental and significant transformation for the large-scale production of fine chemicals, UV and visible light driven photocatalytic systems for alcohol oxidation have been developed, however, the long wavelength near infrared (NIR) and infrared (IR) light have not yet fully utilized by the present photocatalytic systems. Herein, we reported carbon quantum dots (CQDs) can function as an effective near infrared (NIR) light driven photocatalyst for the selective oxidation of benzyl alcohol to benzaldehyde. Based on the NIR light driven photo-induced electron transfer property and its photocatalytic activity for H2O2 decomposition, this metal-free catalyst could realize the transformation from benzyl alcohol to benzaldehyde with high selectivity (100%) and conversion (92%) under NIR light irradiation. HO&z.rad; is the main active oxygen specie in benzyl alcohol selective oxidative reaction confirmed by terephthalic acid photoluminescence probing assay (TA-PL), selecting toluene as the substrate. Such metal-free photocatalytic system also selectively converts other alcohol substrates to their corresponding aldehydes with high conversion, demonstrating a potential application of accessing traditional alcohol oxidation chemistry. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr00092c

Inhibition of TGFβ signaling increases direct conversion of fibroblasts to induced cardiomyocytes.

PubMed

Ifkovits, Jamie L; Addis, Russell C; Epstein, Jonathan A; Gearhart, John D

2014-01-01

Recent studies have been successful at utilizing ectopic expression of transcription factors to generate induced cardiomyocytes (iCMs) from fibroblasts, albeit at a low frequency in vitro. This work investigates the influence of small molecules that have been previously reported to improve differentiation to cardiomyocytes as well as reprogramming to iPSCs in conjunction with ectopic expression of the transcription factors Hand2, Nkx2.5, Gata4, Mef2C, and Tbx5 on the conversion to functional iCMs. We utilized a reporter system in which the calcium indicator GCaMP is driven by the cardiac Troponin T promoter to quantify iCM yield. The TGFβ inhibitor, SB431542 (SB), was identified as a small molecule capable of increasing the conversion of both mouse embryonic fibroblasts and adult cardiac fibroblasts to iCMs up to ∼5 fold. Further characterization revealed that inhibition of TGFβ by SB early in the reprogramming process led to the greatest increase in conversion of fibroblasts to iCMs in a dose-responsive manner. Global transcriptional analysis at Day 3 post-induction of the transcription factors revealed an increased expression of genes associated with the development of cardiac muscle in the presence of SB compared to the vehicle control. Incorporation of SB in the reprogramming process increases the efficiency of iCM generation, one of the major goals necessary to enable the use of iCMs for discovery-based applications and for the clinic.

Inhibition of TGFβ Signaling Increases Direct Conversion of Fibroblasts to Induced Cardiomyocytes

PubMed Central

Ifkovits, Jamie L.; Addis, Russell C.; Epstein, Jonathan A.; Gearhart, John D.

2014-01-01

Recent studies have been successful at utilizing ectopic expression of transcription factors to generate induced cardiomyocytes (iCMs) from fibroblasts, albeit at a low frequency in vitro. This work investigates the influence of small molecules that have been previously reported to improve differentiation to cardiomyocytes as well as reprogramming to iPSCs in conjunction with ectopic expression of the transcription factors Hand2, Nkx2.5, Gata4, Mef2C, and Tbx5 on the conversion to functional iCMs. We utilized a reporter system in which the calcium indicator GCaMP is driven by the cardiac Troponin T promoter to quantify iCM yield. The TGFβ inhibitor, SB431542 (SB), was identified as a small molecule capable of increasing the conversion of both mouse embryonic fibroblasts and adult cardiac fibroblasts to iCMs up to ∼5 fold. Further characterization revealed that inhibition of TGFβ by SB early in the reprogramming process led to the greatest increase in conversion of fibroblasts to iCMs in a dose-responsive manner. Global transcriptional analysis at Day 3 post-induction of the transcription factors revealed an increased expression of genes associated with the development of cardiac muscle in the presence of SB compared to the vehicle control. Incorporation of SB in the reprogramming process increases the efficiency of iCM generation, one of the major goals necessary to enable the use of iCMs for discovery-based applications and for the clinic. PMID:24586958

A Conversation Analytic Study on Teaching Moments Observed in Free Conversations between Japanese and American Friends

ERIC Educational Resources Information Center

Nagai, Ayako

2011-01-01

Utilizing the methodology of Conversation Analysis (CA), this study examines teaching moments observed in free conversations by pairs of Japanese and American friends. CA's detailed turn-by-turn analysis reveals that teaching of vocabulary, idioms, and culture occurs when native speakers orient to the non-nativeness of the other speakers.…

Energy Efficiency and Performance Limiting Effects in Thermo-Osmotic Energy Conversion from Low-Grade Heat.

PubMed

Straub, Anthony P; Elimelech, Menachem

2017-11-07

Low-grade heat energy from sources below 100 °C is available in massive quantities around the world, but cannot be converted to electricity effectively using existing technologies due to variability in the heat output and the small temperature difference between the source and environment. The recently developed thermo-osmotic energy conversion (TOEC) process has the potential to harvest energy from low-grade heat sources by using a temperature difference to create a pressurized liquid flux across a membrane, which can be converted to mechanical work via a turbine. In this study, we perform the first analysis of energy efficiency and the expected performance of the TOEC technology, focusing on systems utilizing hydrophobic porous vapor-gap membranes and water as a working fluid. We begin by developing a framework to analyze realistic mass and heat transport in the process, probing the impact of various membrane parameters and system operating conditions. Our analysis reveals that an optimized system can achieve heat-to-electricity energy conversion efficiencies up to 4.1% (34% of the Carnot efficiency) with hot and cold working temperatures of 60 and 20 °C, respectively, and an operating pressure of 5 MPa (50 bar). Lower energy efficiencies, however, will occur in systems operating with high power densities (>5 W/m 2 ) and with finite-sized heat exchangers. We identify that the most important membrane properties for achieving high performance are an asymmetric pore structure, high pressure resistance, a high porosity, and a thickness of 30 to 100 μm. We also quantify the benefits in performance from utilizing deaerated water streams, strong hydrodynamic mixing in the membrane module, and high heat exchanger efficiencies. Overall, our study demonstrates the promise of full-scale TOEC systems to extract energy from low-grade heat and identifies key factors for performance optimization moving forward.

Life cycle assessment of two emerging sewage sludge-to-energy systems: evaluating energy and greenhouse gas emissions implications.

PubMed

Cao, Yucheng; Pawłowski, Artur

2013-01-01

A "cradle-to-grave" life cycle assessment was conducted to examine the energy and greenhouse gas (GHG) emission footprints of two emerging sludge-to-energy systems. One system employs a combination of anaerobic digestion (AD) and fast pyrolysis for bioenergy conversion, while the other excludes AD. Each system was divided into five process phases: plant construction, sludge pretreatment, sludge-to-bioenergy conversion, bioenergy utilizations and biochar management. Both systems achieved energy and GHG emission benefits, and the AD-involving system performed better than the AD-excluding system (5.30 vs. 0.63 GJ/t sludge in net energy gain and 0.63 vs. 0.47 t CO(2)eq/t sludge in emission credit for base case). Detailed contribution and sensitivity analyses were conducted to identify how and to what degree the different life-cycle phases are responsible for the energy and emission impacts. The energy and emission performances were significantly affected by variations in bioenergy production, energy requirement for sludge drying and end use of bioenergy. Copyright © 2012 Elsevier Ltd. All rights reserved.

Nitrogen cycling in Bioregenerative Life Support Systems: Challenges for waste refinery and food production processes

NASA Astrophysics Data System (ADS)

Clauwaert, Peter; Muys, Maarten; Alloul, Abbas; De Paepe, Jolien; Luther, Amanda; Sun, Xiaoyan; Ilgrande, Chiara; Christiaens, Marlies E. R.; Hu, Xiaona; Zhang, Dongdong; Lindeboom, Ralph E. F.; Sas, Benedikt; Rabaey, Korneel; Boon, Nico; Ronsse, Frederik; Geelen, Danny; Vlaeminck, Siegfried E.

2017-05-01

In order to sustain human life in an isolated environment, an efficient conversion of wasted nutrients to food might become mandatory. This is particularly the case for space missions where resupply from earth or in-situ resource utilization is not possible or desirable. A combination of different technologies is needed to allow full recycling of e.g. nitrogenous compounds in space. In this review, an overview is given of the different essential processes and technologies that enable closure of the nitrogen cycle in Bioregenerative Life Support Systems (BLSS). Firstly, a set of biological and physicochemical refinery stages ensures efficient conversion of waste products into the building blocks, followed by the production of food with a range of biological methods. For each technology, bottlenecks are identified. Furthermore, challenges and outlooks are presented at the integrated system level. Space adaptation and integration deserve key attention to enable the recovery of nitrogen for the production of nutritional food in space, but also in closed loop systems on earth.

Conceptual design of free-piston Stirling conversion system for solar power units

NASA Astrophysics Data System (ADS)

Loktionov, Iu. V.

A conversion system has been conceptually designed for solar power units of the dish-Stirling type. The main design objectives were to demonstrate the possibility of attaining such performance characteristics as low manufacturing and life cycle costs, high reliability, long life, high efficiency, power output stability, self-balance, automatic (or self-) start-up, and easy maintenance. The system design includes a heat transfer and utilization subsystem with a solar receiver, a free-piston engine, an electric power generation subsystem, and a control subsystem. The working fluid is helium. The structural material is stainless steel for hot elements, aluminum alloys and plastics for others. The electric generation subunit can be fabricated in three options: with an induction linear alternator, with a permanent magnet linear alternator, and with a serial rotated induction generator and a hydraulic drive subsystem. The heat transfer system is based on heat pipes or the reflux boiler principle. Several models of heat transfer units using a liquid metal (Na or Na-K) have been created and demonstrated.

Design and field performance of the KENETECH photovoltaic inverter system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Behnke, M.R.

1995-11-01

KENETECH Windpower has recently adapted the power conversion technology developed for the company`s variable speed wind turbine to grid-connected photovoltaic applications. KENETECH PV inverter systems are now in successful operation at the Sacramento Municipal Utility District`s (SMUD) Hedge Substation and the PVUSA-Davis site, with additional systems scheduled to be placed into service by the end of 1995 at SMUD, the New York Power Authority, Xerox Corporation`s Clean Air Now project, and the Georgia Tech Aquatic Center. The features of the inverter are described.

Grumman WS33 wind system: prototype construction and testing, Phase II technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adler, F.M.; Henton, P.; King, P.W.

1980-11-01

The prototype fabrication and testing of the 8 kW small wind energy conversion system are reported. The turbine is a three-bladed, down-wind machine designed to interface directly with an electrical utility network. The machine as finally fabricated is rated at 15 kW at 24 mpH and peak power of 18 kW at 35 mph. Utility compatible electrical power is generated in winds between a cut-in speed of 9 mph and a cut-out speed of 35 mph by using the torque characteristics of the unit's induction generator combined with the rotor aerodynamics to maintain essentially constant speed. Inspection procedures, pre-delivery testing,more » and a cost analysis are included.« less

Conditional genomic rearrangement by designed meiotic recombination using VDE (PI-SceI) in yeast.

PubMed

Fukuda, Tomoyuki; Ohya, Yoshikazu; Ohta, Kunihiro

2007-10-01

Meiotic recombination plays critical roles in the acquisition of genetic diversity and has been utilized for conventional breeding of livestock and crops. The frequency of meiotic recombination is normally low, and is extremely low in regions called "recombination cold domains". Here, we describe a new and highly efficient method to modulate yeast meiotic gene rearrangements using VDE (PI-SceI), an intein-encoded endonuclease that causes an efficient unidirectional meiotic gene conversion at its recognition sequence (VRS). We designed universal targeting vectors, by use of which the strain that inserts the VRS at a desired site is acquired. Meiotic induction of the strains provided unidirectional gene conversions and frequent genetic rearrangements of flanking genes with little impact on cell viability. This system thus opens the way for the designed modulation of meiotic gene rearrangements, regardless of recombinational activity of chromosomal domains. Finally, the VDE-VRS system enabled us to conduct meiosis-specific conditional knockout of genes where VDE-initiated gene conversion disrupts the target gene during meiosis, serving as a novel approach to examine the functions of genes during germination of resultant spores.

Impact of Predicting Health Care Utilization Via Web Search Behavior: A Data-Driven Analysis.

PubMed

Agarwal, Vibhu; Zhang, Liangliang; Zhu, Josh; Fang, Shiyuan; Cheng, Tim; Hong, Chloe; Shah, Nigam H

2016-09-21

By recent estimates, the steady rise in health care costs has deprived more than 45 million Americans of health care services and has encouraged health care providers to better understand the key drivers of health care utilization from a population health management perspective. Prior studies suggest the feasibility of mining population-level patterns of health care resource utilization from observational analysis of Internet search logs; however, the utility of the endeavor to the various stakeholders in a health ecosystem remains unclear. The aim was to carry out a closed-loop evaluation of the utility of health care use predictions using the conversion rates of advertisements that were displayed to the predicted future utilizers as a surrogate. The statistical models to predict the probability of user's future visit to a medical facility were built using effective predictors of health care resource utilization, extracted from a deidentified dataset of geotagged mobile Internet search logs representing searches made by users of the Baidu search engine between March 2015 and May 2015. We inferred presence within the geofence of a medical facility from location and duration information from users' search logs and putatively assigned medical facility visit labels to qualifying search logs. We constructed a matrix of general, semantic, and location-based features from search logs of users that had 42 or more search days preceding a medical facility visit as well as from search logs of users that had no medical visits and trained statistical learners for predicting future medical visits. We then carried out a closed-loop evaluation of the utility of health care use predictions using the show conversion rates of advertisements displayed to the predicted future utilizers. In the context of behaviorally targeted advertising, wherein health care providers are interested in minimizing their cost per conversion, the association between show conversion rate and predicted utilization score, served as a surrogate measure of the model's utility. We obtained the highest area under the curve (0.796) in medical visit prediction with our random forests model and daywise features. Ablating feature categories one at a time showed that the model performance worsened the most when location features were dropped. An online evaluation in which advertisements were served to users who had a high predicted probability of a future medical visit showed a 3.96% increase in the show conversion rate. Results from our experiments done in a research setting suggest that it is possible to accurately predict future patient visits from geotagged mobile search logs. Results from the offline and online experiments on the utility of health utilization predictions suggest that such prediction can have utility for health care providers.

Impact of Predicting Health Care Utilization Via Web Search Behavior: A Data-Driven Analysis

PubMed Central

Zhang, Liangliang; Zhu, Josh; Fang, Shiyuan; Cheng, Tim; Hong, Chloe; Shah, Nigam H

2016-01-01

Background By recent estimates, the steady rise in health care costs has deprived more than 45 million Americans of health care services and has encouraged health care providers to better understand the key drivers of health care utilization from a population health management perspective. Prior studies suggest the feasibility of mining population-level patterns of health care resource utilization from observational analysis of Internet search logs; however, the utility of the endeavor to the various stakeholders in a health ecosystem remains unclear. Objective The aim was to carry out a closed-loop evaluation of the utility of health care use predictions using the conversion rates of advertisements that were displayed to the predicted future utilizers as a surrogate. The statistical models to predict the probability of user’s future visit to a medical facility were built using effective predictors of health care resource utilization, extracted from a deidentified dataset of geotagged mobile Internet search logs representing searches made by users of the Baidu search engine between March 2015 and May 2015. Methods We inferred presence within the geofence of a medical facility from location and duration information from users’ search logs and putatively assigned medical facility visit labels to qualifying search logs. We constructed a matrix of general, semantic, and location-based features from search logs of users that had 42 or more search days preceding a medical facility visit as well as from search logs of users that had no medical visits and trained statistical learners for predicting future medical visits. We then carried out a closed-loop evaluation of the utility of health care use predictions using the show conversion rates of advertisements displayed to the predicted future utilizers. In the context of behaviorally targeted advertising, wherein health care providers are interested in minimizing their cost per conversion, the association between show conversion rate and predicted utilization score, served as a surrogate measure of the model’s utility. Results We obtained the highest area under the curve (0.796) in medical visit prediction with our random forests model and daywise features. Ablating feature categories one at a time showed that the model performance worsened the most when location features were dropped. An online evaluation in which advertisements were served to users who had a high predicted probability of a future medical visit showed a 3.96% increase in the show conversion rate. Conclusions Results from our experiments done in a research setting suggest that it is possible to accurately predict future patient visits from geotagged mobile search logs. Results from the offline and online experiments on the utility of health utilization predictions suggest that such prediction can have utility for health care providers. PMID:27655225

Design, modeling, and analysis of a feedstock logistics system.

PubMed

Judd, Jason D; Sarin, Subhash C; Cundiff, John S

2012-01-01

Given the location of a bio-energy plant for the conversion of biomass to bio-energy, a feedstock logistics system that relies on the use of satellite storage locations (SSLs) for temporary storage and loading of round bales is proposed. Three equipment systems are considered for handling biomass at the SSLs, and they are either placed permanently or are mobile and thereby travel from one SSL to another. A mathematical programming-based approach is utilized to determine SSLs and equipment routes in order to minimize the total cost. The use of a Side-loading Rack System results in average savings of 21.3% over a Densification System while a Rear-loading Rack System is more expensive to operate than either of the other equipment systems. The utilization of mobile equipment results in average savings of 14.8% over the equipment placed permanently. Furthermore, the Densification System is not justifiable for transportation distances less than 81 km. Copyright © 2011 Elsevier Ltd. All rights reserved.

A summary of the status of biomass conversion technologies and opportunities for their use in developing countries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Waddle, D.B.; Perlack, R.D.; Wimberly, J.

1990-01-01

Biomass plays a significant role in energy use in developing countries: however, these resources are often used very inefficiently. Recent technology developments have made possible improved conversion efficiencies for utility scale technologies. These developments may be of interest in the wake of recent policy changes occurring in several developing countries, with respect to independent power production. Efforts are also being directed at developing biomass conversion technologies that can interface and/or compete with internal combustion engines for small, isolated loads. This paper reviews the technological status of biomass conversion technologies appropriate for commercial, industrial, and small utility applications in developing countries.more » Market opportunities, constraints, and technology developments are also discussed. 25 refs., 1 fig., 1 tab.« less

Gas-turbine critical research and advanced technology support project

NASA Technical Reports Server (NTRS)

Clark, J. S.; Lowell, C. E.; Niedzwiecki, R. W.; Nainiger, J. J.

1979-01-01

The technical progress made during the first 15 months of a planned 40-month project to provide a critical-technology data base for utility gas-turbine systems capable of burning coal-derived fuels is summarized. Tasks were included in the following areas: (1) combustion, to study the combustion of coal-derived fuels and conversion of fuel-bound nitrogen to NOx; (2) materials, to understand and prevent hot corrosion; and (3) system studies, to integrate and guide the other technologies. Significant progress was made.

Design of a photovoltaic system for a temperate climate all-electric residence

NASA Astrophysics Data System (ADS)

Mehalick, E. M.; Tully, G. F.; Johnson, J.; Truncellito, N.; Schaeffer, R.

1982-01-01

A photovoltaic system was developed and integrated into a single story residence having low space conditioning loads typical of a temperate climate similar to Santa Maria, CA. The design addresses the residential market segment of low energy consuming houses with limited roof area availability; in fact the garage roof is used for the array. The array size to meet the requirements of this type of house covers 40 square m with a rated power output of 4.3 kW at NOCT conditions. A flexible array installation is presented which can be implemented as an integral mount or a stand-off mount depending on the homeowner preference. A 4 kW utility-tied inverter is used in the power conversion subsystem, representative of currently available hardware. The system provides feedback of excess energy to the utility which is the most promising approach for grid-connected residential systems in the mid 1980's.

Evaluation of a Digital Companion for Older Adults with Mild Cognitive Impairment.

PubMed

Demiris, George; Thompson, Hilaire J; Lazar, Amanda; Lin, Shih-Yin

2016-01-01

Study Objective: The purpose of this study was to examine the feasibility of a digital companion system used by older adults with mild cognitive impairment (MCI). We utilized a commercially available system that is comprehensive in its functionalities (including conversation ability, use of pictures and other media, and reminders) to explore the system's impact on older adults ' social interactions, anxiety, depressive symptoms, and acceptance of the system. Study Design: We conducted a three-month mixed methods evaluation study of the digital companion. Results: Ten female community-dwelling older adults (average age 78.3 years) participated in the study. Overall, participants utilized the tool regularly and appreciated its presence and their interactions. Participants scored higher at the end of the study in cognition and social support scales, and lower in presence of depressive symptoms. Conclusion: Findings indicate the feasibility of a digital companion for people with MCI and inform the need for additional research.

Technology and development requirements for advanced coal conversion systems

NASA Technical Reports Server (NTRS)

1981-01-01

A compendium of coal conversion process descriptions is presented. The SRS and MC data bases were utilized to provide information paticularly in the areas of existing process designs and process evaluations. Additional information requirements were established and arrangements were made to visit process developers, pilot plants, and process development units to obtain information that was not otherwise available. Plant designs, process descriptions and operating conditions, and performance characteristics were analyzed and requirements for further development identified and evaluated to determine the impact of these requirements on the process commercialization potential from the standpoint of economics and technical feasibility. A preliminary methodology was established for the comparative technical and economic assessment of advanced processes.

Liquid-assisted grinding and ion pairing regulates percentage conversion and diastereoselectivity of the Wittig reaction under mechanochemical conditions.

PubMed

Denlinger, Kendra Leahy; Ortiz-Trankina, Lianna; Carr, Preston; Benson, Kingsley; Waddell, Daniel C; Mack, James

2018-01-01

Mechanochemistry is maturing as a discipline and continuing to grow, so it is important to continue understanding the rules governing the system. In a mechanochemical reaction, the reactants are added into a vessel along with one or more grinding balls and the vessel is shaken at high speeds to facilitate a chemical reaction. The dielectric constant of the solvent used in liquid-assisted grinding (LAG) and properly chosen counter-ion pairing increases the percentage conversion of stilbenes in a mechanochemical Wittig reaction. Utilizing stepwise addition/evaporation of ethanol in liquid-assisted grinding also allows for the tuning of the diastereoselectivity in the Wittig reaction.

Selective CO2 conversion to formate conjugated with H2O oxidation utilizing semiconductor/complex hybrid photocatalysts.

PubMed

Sato, Shunsuke; Arai, Takeo; Morikawa, Takeshi; Uemura, Keiko; Suzuki, Tomiko M; Tanaka, Hiromitsu; Kajino, Tsutomu

2011-10-05

Photoelectrochemical reduction of CO(2) to HCOO(-) (formate) over p-type InP/Ru complex polymer hybrid photocatalyst was highly enhanced by introducing an anchoring complex into the polymer. By functionally combining the hybrid photocatalyst with TiO(2) for water oxidation, selective photoreduction of CO(2) to HCOO(-) was achieved in aqueous media, in which H(2)O was used as both an electron donor and a proton source. The so-called Z-scheme (or two-step photoexcitation) system operated with no external electrical bias. The selectivity for HCOO(-) production was >70%, and the conversion efficiency of solar energy to chemical energy was 0.03-0.04%.

Conversion of blackbody radiation into laser energy

NASA Technical Reports Server (NTRS)

Mcinville, R. M.; Hassan, H. A.

1982-01-01

By employing detailed kinetic models, three concepts which utilize a blackbody cavity for the conversion of solar energy into laser energy using a CO2 lasant are analyzed and compared. In the first, the blackbody radiation is used to excite flowing CO2 directly. The second and third employ a mixing laser concept with CO and N2 being the donor gases. The CO is optically pumped while thermal heating excites the N2. Blackbody temperatures ranging from 1500 deg K - 2500 deg K are considered. Based on calculated laser power output per unit flow rate of CO2, it appears that the N2-CO2 mixing laser is the most attractive system.

Nucleic acid compositions and the encoding proteins

DOEpatents

Preston, III, James F.; Chow, Virginia; Nong, Guang; Rice, John D.; St. John, Franz J.

2014-09-02

The subject invention provides at least one nucleic acid sequence encoding an aldouronate-utilization regulon isolated from Paenibacillus sp. strain JDR-2, a bacterium which efficiently utilizes xylan and metabolizes aldouronates (methylglucuronoxylosaccharides). The subject invention also provides a means for providing a coordinately regulated process in which xylan depolymerization and product assimilation are coupled in Paenibacillus sp. strain JDR-2 to provide a favorable system for the conversion of lignocellulosic biomass to biobased products. Additionally, the nucleic acid sequences encoding the aldouronate-utilization regulon can be used to transform other bacteria to form organisms capable of producing a desired product (e.g., ethanol, 1-butanol, acetoin, 2,3-butanediol, 1,3-propanediol, succinate, lactate, acetate, malate or alanine) from lignocellulosic biomass.

Preliminary design of an advanced Stirling system for terrestrial solar energy conversion

NASA Astrophysics Data System (ADS)

White, M. A.; Noble, J. E.; Emigh, S. G.; Ross, B. A.; Lehmann, G. A.

A preliminary design was generated for an advanced Stirling conversion system (ASCS) that will be capable of delivering about 25 kW of electric power to an electric utility grid. Stirling engines are being evaluated for terrestrial solar applications. A two-year task to complete detailed design, fabrication, assembly and testing of an ASCS prototype began in April, 1990. The ASCS is designed to deliver maximum power per year over a range of solar inputs with a design life of 30 years (60,000 h). The ACSC has a long-term cost goal of about $450 per kilowatt, exclusive of the 11-m parabolic dish concentrator. The proposed system includes a Stirling engine with high-pressure hydraulic output, coupled with a bent axis variable displacement hydraulic motor and a rotary induction generator. The major thrusts of the preliminary design are described, including material selection for the hot-end components, heat transport system (reflux pool boiler) design, system thermal response, improved manufacturability, FMECA/FTA analysis, updated manufacturing cost estimate, and predicted system performance.

Preliminary design of an advanced Stirling system for terrestrial solar energy conversion

NASA Technical Reports Server (NTRS)

White, M. A.; Noble, J. E.; Emigh, S. G.; Ross, B. A.; Lehmann, G. A.

1990-01-01

A preliminary design was generated for an advanced Stirling conversion system (ASCS) that will be capable of delivering about 25 kW of electric power to an electric utility grid. Stirling engines are being evaluated for terrestrial solar applications. A two-year task to complete detailed design, fabrication, assembly and testing of an ASCS prototype began in April, 1990. The ASCS is designed to deliver maximum power per year over a range of solar inputs with a design life of 30 years (60,000 h). The ACSC has a long-term cost goal of about $450 per kilowatt, exclusive of the 11-m parabolic dish concentrator. The proposed system includes a Stirling engine with high-pressure hydraulic output, coupled with a bent axis variable displacement hydraulic motor and a rotary induction generator. The major thrusts of the preliminary design are described, including material selection for the hot-end components, heat transport system (reflux pool boiler) design, system thermal response, improved manufacturability, FMECA/FTA analysis, updated manufacturing cost estimate, and predicted system performance.

Technologies for the Comprehensive Exploitation of the Geothermal Resources of the North Caucasus Region

NASA Astrophysics Data System (ADS)

Alkhasov, A. B.

2018-03-01

Technology for the integrated development of low-temperature geothermal resources using the thermal and water potentials for various purposes is proposed. The heat of the thermal waters is utilized in a low-temperature district heating system and for heating the water in a hot water supply system. The water cooled in heat exchangers enters a chemical treatment system where it is conditioned into potable water quality and then forwarded to the household and potable water supply system. Efficient technologies for removal of arsenic and organic contaminants from the water have been developed. For the uninterrupted supply of the consumers with power, the technologies that use two and more types of renewable energy sources (RESs) have the best prospects. Technology for processing organic waste using the geothermal energy has been proposed. According to this technology, the geothermal water is divided into two flows, one of which is delivered to a biomass conversion system and the other is directed to a geothermal steam-gas power plant (GSGP). The wastewater arrives at the pump station from which it is pumped back into the bed. Upon drying, the biogas from the conversion system is delivered into the combustion chamber of a gas-turbine plant (GTP). The heat of the turbine exhaust gases is used in the GSGP to evaporate and reheat the low-boiling working medium. The working medium is heated in the GSGP to the evaporation temperature using the heat of the thermal water. High-temperature geothermal brines are the most promising for the comprehensive processing. According to the proposed technology, the heat energy of the brines is utilized to generate the electric power at a binary geothermal power station; the electric power is then used to extract the dissolved chemical components from the rest of the brine. The comprehensive utilization of high-temperature brines of the East-Precaucasian Artesian Basin will allow to completely satisfy the demand of Russia for lithium carbonate and sodium chloride.

Exceeding the solar cell Shockley-Queisser limit via thermal up-conversion of low-energy photons

NASA Astrophysics Data System (ADS)

Boriskina, Svetlana V.; Chen, Gang

2014-03-01

Maximum efficiency of ideal single-junction photovoltaic (PV) cells is limited to 33% (for 1 sun illumination) by intrinsic losses such as band edge thermalization, radiative recombination, and inability to absorb below-bandgap photons. This intrinsic thermodynamic limit, named after Shockley and Queisser (S-Q), can be exceeded by utilizing low-energy photons either via their electronic up-conversion or via the thermophotovoltaic (TPV) conversion process. However, electronic up-conversion systems have extremely low efficiencies, and practical temperature considerations limit the operation of TPV converters to the narrow-gap PV cells. Here we develop a conceptual design of a hybrid TPV platform, which exploits thermal up-conversion of low-energy photons and is compatible with conventional silicon PV cells by using spectral and directional selectivity of the up-converter. The hybrid platform offers sunlight-to-electricity conversion efficiency exceeding that imposed by the S-Q limit on the corresponding PV cells across a broad range of bandgap energies, under low optical concentration (1-300 suns), operating temperatures in the range 900-1700 K, and in simple flat panel designs. We demonstrate maximum conversion efficiency of 73% under illumination by non-concentrated sunlight. A detailed analysis of non-ideal hybrid platforms that allows for up to 15% of absorption/re-emission losses yields limiting efficiency value of 45% for Si PV cells.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rhinefrank, Kenneth E.; Lenee-Bluhm, Pukha; Prudell, Joseph H.

The most prudent path to a full-scale design, build and deployment of a wave energy conversion (WEC) system involves establishment of validated numerical models using physical experiments in a methodical scaling program. This Project provides essential additional rounds of wave tank testing at 1:33 scale and ocean/bay testing at a 1:7 scale, necessary to validate numerical modeling that is essential to a utility-scale WEC design and associated certification.

NAVFAC Ocean Thermal Energy Conversion (OTEC) Project; OTEC System Design Report

DTIC Science & Technology

2010-11-16

191 Figure 3-129. Web illustration of a magnetically coupled pump ...............................................192 Figure 3-130...utility air at a suitable water dew point. Two 100% capacity rotary screw compressors, dryer and receiver shall be installed to serve process and...remora centerline, with positive TCG out of the paper and negative TCG into the paper . The CG of the remora in its vertical orientation is

Solar-thermal conversion and thermal energy storage of graphene foam-based composites.

PubMed

Zhang, Lianbin; Li, Renyuan; Tang, Bo; Wang, Peng

2016-08-14

Among various utilizations of solar energy, solar-thermal conversion has recently gained renewed research interest due to its extremely high energy efficiency. However, one limiting factor common to all solar-based energy conversion technologies is the intermittent nature of solar irradiation, which makes them unable to stand-alone to satisfy the continuous energy need. Herein, we report a three-dimensional (3D) graphene foam and phase change material (PCM) composite for the seamlessly combined solar-thermal conversion and thermal storage for sustained energy release. The composite is obtained by infiltrating the 3D graphene foam with a commonly used PCM, paraffin wax. The high macroporosity and low density of the graphene foam allow for high weight fraction of the PCM to be incorporated, which enhances the heat storage capacity of the composite. The interconnected graphene sheets in the composite provide (1) the solar-thermal conversion capability, (2) high thermal conductivity and (3) form stability of the composite. Under light irradiation, the composite effectively collects and converts the light energy into thermal energy, and the converted thermal energy is stored in the PCM and released in an elongated period of time for sustained utilization. This study provides a promising route for sustainable utilization of solar energy.

Emergy evaluation of water utilization benefits in water-ecological-economic system based on water cycle process

NASA Astrophysics Data System (ADS)

Guo, X.; Wu, Z.; Lv, C.

2017-12-01

The water utilization benefits are formed by the material flow, energy flow, information flow and value stream in the whole water cycle process, and reflected along with the material circulation of inner system. But most of traditional water utilization benefits evaluation are based on the macro level, only consider the whole material input and output and energy conversion relation, and lack the characterization of water utilization benefits accompanying with water cycle process from the formation mechanism. In addition, most studies are from the perspective of economics, only pay attention to the whole economic output and sewage treatment economic investment, but neglect the ecological function benefits of water cycle, Therefore, from the perspective of internal material circulation in the whole system, taking water cycle process as the process of material circulation and energy flow, the circulation and flow process of water and other ecological environment, social economic elements were described, and the composition of water utilization positive and negative benefits in water-ecological-economic system was explored, and the performance of each benefit was analyzed. On this basis, the emergy calculation method of each benefit was proposed by emergy quantitative analysis technique, which can realize the unified measurement and evaluation of water utilization benefits in water-ecological-economic system. Then, taking Zhengzhou city as an example, the corresponding benefits of different water cycle links were calculated quantitatively by emergy method, and the results showed that the emergy evaluation method of water utilization benefits can unify the ecosystem and the economic system, achieve uniform quantitative analysis, and measure the true value of natural resources and human economic activities comprehensively.

Discovering Inexpensive, Effective Catalysts for Solar Energy Conversion: An Authentic Research Laboratory Experience

ERIC Educational Resources Information Center

Shaner, Sarah E.; Hooker, Paul D.; Nickel, Anne-Marie; Leichtfuss, Amanda R.; Adams, Carissa S.; de la Cerda, Dionisia; She, Yuqi; Gerken, James B.; Pokhrel, Ravi; Ambrose, Nicholas J.; Khaliqi, David; Stahl, Shannon S.; Schuttlefield Christus, Jennifer D.

2016-01-01

Electrochemical water oxidation is a major focus of solar energy conversion efforts. A new laboratory experiment has been developed that utilizes real-time, hands-on research to discover catalysts for solar energy conversion. The HARPOON, or Heterogeneous Anodes Rapidly Perused for Oxygen Overpotential Neutralization, experiment allows an array of…

Potential active materials for photo-supercapacitor: A review

NASA Astrophysics Data System (ADS)

Ng, C. H.; Lim, H. N.; Hayase, S.; Harrison, I.; Pandikumar, A.; Huang, N. M.

2015-11-01

The need for an endless renewable energy supply, typically through the utilization of solar energy in most applications and systems, has driven the expansion, versatility, and diversification of marketed energy storage devices. Energy storage devices such as hybridized dye-sensitized solar cell (DSSC)-capacitors and DSSC-supercapacitors have been invented for energy reservation. The evolution and vast improvement of these devices in terms of their efficiencies and flexibilities have further sparked the invention of the photo-supercapacitor. The idea of coupling a DSSC and supercapacitor as a complete energy conversion and storage device arose because the solar energy absorbed by dye molecules can be efficiently transferred and converted to electrical energy by adopting a supercapacitor as the energy delivery system. The conversion efficiency of a photo-supercapacitor is mainly dependent on the use of active materials during its fabrication. The performances of the dye, photoactive metal oxide, counter electrode, redox electrolyte, and conducting polymer are the primary factors contributing to high-energy-efficient conversion, which enhances the performance and shelf-life of a photo-supercapacitor. Moreover, the introduction of compact layer as a primary adherent film has been earmarked as an effort in enhancing power conversion efficiency of solar cell. Additionally, the development of electrolyte-free solar cell such as the invention of hole-conductor or perovskite solar cell is currently being explored extensively. This paper reviews and analyzes the potential active materials for a photo-supercapacitor to enhance the conversion and storage efficiencies.

Energy conservation in coal conversion. Final report, September 15, 1977--September 1, 1978. Selected case studies and conservation methodologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Purcupile, J.C.

The purpose of this study is to apply the methodologies developed in the Energy Conservation in Coal Conversion August, 1977 Progress Report - Contract No. EY77S024196 - to an energy efficient, near-term coal conversion process design, and to develop additional, general techniques for studying energy conservation and utilization in coal conversion processes. The process selected for study was the Ralph M. Parsons Company of Pasadena, California ''Oil/Gas Complex, Conceptual Design/Economic Analysis'' as described in R and D Report No. 114 - Interim Report No. 4, published March, 1977, ERDA Contract No. E(49-18)-1975. Thirteen papers representing possible alternative methods of energymore » conservation or waste heat utilization have been entered individually into EDB and ERA. (LTN)« less

Enhanced energy conversion efficiency from high strength synthetic organic wastewater by sequential dark fermentative hydrogen production and algal lipid accumulation.

PubMed

Ren, Hong-Yu; Liu, Bing-Feng; Kong, Fanying; Zhao, Lei; Xing, Defeng; Ren, Nan-Qi

2014-04-01

A two-stage process of sequential dark fermentative hydrogen production and microalgal cultivation was applied to enhance the energy conversion efficiency from high strength synthetic organic wastewater. Ethanol fermentation bacterium Ethanoligenens harbinense B49 was used as hydrogen producer, and the energy conversion efficiency and chemical oxygen demand (COD) removal efficiency reached 18.6% and 28.3% in dark fermentation. Acetate was the main soluble product in dark fermentative effluent, which was further utilized by microalga Scenedesmus sp. R-16. The final algal biomass concentration reached 1.98gL(-1), and the algal biomass was rich in lipid (40.9%) and low in protein (23.3%) and carbohydrate (11.9%). Compared with single dark fermentation stage, the energy conversion efficiency and COD removal efficiency of two-stage system remarkably increased 101% and 131%, respectively. This research provides a new approach for efficient energy production and wastewater treatment using a two-stage process combining dark fermentation and algal cultivation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Anaerobic Digestion.

PubMed

Liebetrau, Jan; Sträuber, Heike; Kretzschmar, Jörg; Denysenko, Velina; Nelles, Michael

2017-04-09

The term anaerobic digestion usually refers to the microbial conversion of organic material to biogas, which mainly consists of methane and carbon dioxide. The technical application of the naturally-occurring process is used to provide a renewable energy carrier and - as the substrate is often waste material - to reduce the organic matter content of the substrate prior to disposal.Applications can be found in sewage sludge treatment, the treatment of industrial and municipal solid wastes and wastewaters (including landfill gas utilization), and the conversion of agricultural residues and energy crops.For biorefinery concepts, the anaerobic digestion (AD) process is, on the one hand, an option to treat organic residues from other production processes. Concomitant effects are the reduction of organic carbon within the treated substance, the conversion of nitrogen and sulfur components, and the production of an energy-rich gas - the biogas. On the other hand, the multistep conversion of complex organic material offers the possibility of interrupting the conversion chain and locking out intermediates for utilization as basic material within the chemical industry.

Status of wind-energy conversion

NASA Technical Reports Server (NTRS)

Thomas, R. L.; Savino, J. M.

1973-01-01

The utilization of wind energy is technically feasible as evidenced by the many past demonstrations of wind generators. The cost of energy from the wind has been high compared to fossil fuel systems; a sustained development effort is needed to obtain economical systems. The variability of the wind makes it an unreliable source on a short term basis. However, the effects of this variability can be reduced by storage systems or connecting wind generators to: (1) fossil fuel systems; (2) hydroelectric systems; or (3) dispersing them throughout a large grid network. Wind energy appears to have the potential to meet a significant amount of our energy needs.

A Commercialization Roadmap for Carbon-Negative Energy Systems

NASA Astrophysics Data System (ADS)

Sanchez, D.

2016-12-01

The Intergovernmental Panel on Climate Change (IPCC) envisages the need for large-scale deployment of net-negative CO2 emissions technologies by mid-century to meet stringent climate mitigation goals and yield a net drawdown of atmospheric carbon. Yet there are few commercial deployments of BECCS outside of niche markets, creating uncertainty about commercialization pathways and sustainability impacts at scale. This uncertainty is exacerbated by the absence of a strong policy framework, such as high carbon prices and research coordination. Here, we propose a strategy for the potential commercial deployment of BECCS. This roadmap proceeds via three steps: 1) via capture and utilization of biogenic CO2 from existing bioenergy facilities, notably ethanol fermentation, 2) via thermochemical co-conversion of biomass and fossil fuels, particularly coal, and 3) via dedicated, large-scale BECCS. Although biochemical conversion is a proven first market for BECCS, this trajectory alone is unlikely to drive commercialization of BECCS at the gigatonne scale. In contrast to biochemical conversion, thermochemical conversion of coal and biomass enables large-scale production of fuels and electricity with a wide range of carbon intensities, process efficiencies and process scales. Aside from systems integration, primarily technical barriers are involved in large-scale biomass logistics, gasification and gas cleaning. Key uncertainties around large-scale BECCS deployment are not limited to commercialization pathways; rather, they include physical constraints on biomass cultivation or CO2 storage, as well as social barriers, including public acceptance of new technologies and conceptions of renewable and fossil energy, which co-conversion systems confound. Despite sustainability risks, this commercialization strategy presents a pathway where energy suppliers, manufacturers and governments could transition from laggards to leaders in climate change mitigation efforts.

Space-based solar power conversion and delivery systems study. Volume 4: Energy conversion systems studies

NASA Technical Reports Server (NTRS)

1977-01-01

Solar cells and optical configurations for the SSPS were examined. In this task, three specific solar cell materials were examined: single crystal silicon, single crystal gallium arsenide, and polycrystalline cadmium sulfide. The comparison of the three different cells on the basis of a subsystem parametric cost per kW of SSPS-generated power at the terrestrial utility interface showed that gallium arsenide was the most promising solar cell material at high concentration ratios. The most promising solar cell material with no concentration, was dependent upon the particular combination of parameters representing cost, mass and performance that were chosen to represent each cell in this deterministic comparative analysis. The potential for mass production, based on the projections of the present state-of-the-art would tend to favor cadmium sulfide in lieu of single crystal silicon or gallium arsenide solar cells.

Thin concentrator photovoltaic module with micro-solar cells which are mounted by self-align method using surface tension of melted solder

NASA Astrophysics Data System (ADS)

Hayashi, Nobuhiko; Terauchi, Masaharu; Aya, Youichirou; Kanayama, Shutetsu; Nishitani, Hikaru; Nakagawa, Tohru; Takase, Michihiko

2017-09-01

We are developing a thin and lightweight CPV module using small size lens system made from poly methyl methacrylate (PMMA) with a short focal length and micro-solar cells to decrease the transporting and the installing costs of CPV systems. In order to achieve high conversion efficiency in CPV modules using micro-solar cells, the micro-solar cells need to be mounted accurately to the irradiated region of the concentrated sunlight. In this study, we have successfully developed self-align method thanks to the surface tension of the melted solder even utilizing commercially available surface-mounting technology (SMT). Solar cells were self-aligned to the specified positions of the circuit board by this self-align method with accuracy within ±10 µm. We actually fabricated CPV modules using this self-align method and demonstrated high conversion efficiency of our CPV module.

Static DC to DC Power Conditioning-Active Ripple Filter, 1 MHZ DC to DC Conversion, and Nonlinear Analysis. Ph.D. Thesis; [voltage regulation and conversion circuitry for spacecraft power supplies

NASA Technical Reports Server (NTRS)

Sander, W. A., III

1973-01-01

Dc to dc static power conditioning systems on unmanned spacecraft have as their inputs highly fluctuating dc voltages which they condition to regulated dc voltages. These input voltages may be less than or greater than the desired regulated voltages. The design of two circuits which address specific problems in the design of these power conditioning systems and a nonlinear analysis of one of the circuits are discussed. The first circuit design is for a nondissipative active ripple filter which uses an operational amplifier to amplify and cancel the sensed ripple voltage. A dc to dc converter operating at a switching frequency of 1 MHz is the second circuit discussed. A nonlinear analysis of the type of dc to dc converter utilized in designing the 1 MHz converter is included.

Economic analysis of small wind-energy conversion systems

NASA Astrophysics Data System (ADS)

Haack, B. N.

1982-05-01

A computer simulation was developed for evaluating the economics of small wind energy conversion systems (SWECS). Input parameters consisted of initial capital investment, maintenance and operating costs, the cost of electricity from other sources, and the yield of electricity. Capital costs comprised the generator, tower, necessity for an inverter and/or storage batteries, and installation, in addition to interest on loans. Wind data recorded every three hours for one year in Detroit, MI was employed with a 0.16 power coefficient to extrapolate up to hub height as an example, along with 10 yr of use variances. A maximum return on investment was found to reside in using all the energy produced on site, rather than selling power to the utility. It is concluded that, based on a microeconomic analysis, SWECS are economically viable at present only where electric rates are inordinately high, such as in remote regions or on islands.

Phosphoenolpyruvate:glucose phosphotransferase system modification increases the conversion rate during L-tryptophan production in Escherichia coli.

PubMed

Liu, Lina; Chen, Sheng; Wu, Jing

2017-10-01

Escherichia coli FB-04(pta1), a recombinant L-tryptophan production strain, was constructed in our laboratory. However, the conversion rate (L-tryptophan yield per glucose) of this strain is somewhat low. In this study, additional genes have been deleted in an effort to increase the conversion rate of E. coli FB-04(pta1). Initially, the pykF gene, which encodes pyruvate kinase I (PYKI), was inactivated to increase the accumulation of phosphoenolpyruvate, a key L-tryptophan precursor. The resulting strain, E. coli FB-04(pta1)ΔpykF, showed a slightly higher L-tryptophan yield and a higher conversion rate in fermentation processes. To further improve the conversion rate, the phosphoenolpyruvate:glucose phosphotransferase system (PTS) was disrupted by deleting the ptsH gene, which encodes the phosphocarrier protein (HPr). The levels of biomass, L-tryptophan yield, and conversion rate of this strain, E. coli FB-04(pta1)ΔpykF/ptsH, were especially low during fed-batch fermentation process, even though it achieved a significant increase in conversion rate during shake-flask fermentation. To resolve this issue, four HPr mutations (N12S, N12A, S46A, and S46N) were introduced into the genomic background of E. coli FB-04(pta1)ΔpykF/ptsH, respectively. Among them, the strain harboring the N12S mutation (E. coli FB-04(pta1)ΔpykF-ptsHN12S) showed a prominently increased conversion rate of 0.178 g g -1 during fed-batch fermentation; an increase of 38.0% compared with parent strain E. coli FB-04(pta1). Thus, mutation of the genomic of ptsH gene provided an alternative method to weaken the PTS and improve the efficiency of carbon source utilization.

Auto-flotation of heterocyst enables the efficient production of renewable energy in cyanobacteria

PubMed Central

Chen, Ming; Li, Jihong; Zhang, Lei; Chang, Sandra; Liu, Chen; Wang, Jianlong; Li, Shizhong

2014-01-01

Utilizing cyanobacteria as a bioenergy resource is difficult due to the cost and energy consuming harvests of microalgal biomass. In this study, an auto-floating system was developed by increasing the photobiological H2 production in the heterocysts of filamentous cyanobacteria. An amount of 1.0 μM of diuron, which inhibited O2 production in cyanobacteria, resulted in a high rate of H2 production in heterocysts. The auto-floating process recovered 91.71% ± 1.22 of the accumulated microalgal biomass from the liquid media. Quantification analysis revealed that 0.72–1.10 μmol H2 per mg dry weight microalgal biomass was necessary to create this auto-floating system. Further bio-conversion by using anaerobic digestion converted the harvested microalgal biomass into biogas. Through this novel coupled system of photobiological H2 production and anaerobic digestion, a high level of light energy conversion efficiency from solar energy to bioenergy was attained with the values of 3.79% ± 0.76. PMID:24499777

The development of automated behavior analysis software

NASA Astrophysics Data System (ADS)

Jaana, Yuki; Prima, Oky Dicky A.; Imabuchi, Takashi; Ito, Hisayoshi; Hosogoe, Kumiko

2015-03-01

The measurement of behavior for participants in a conversation scene involves verbal and nonverbal communications. The measurement validity may vary depending on the observers caused by some aspects such as human error, poorly designed measurement systems, and inadequate observer training. Although some systems have been introduced in previous studies to automatically measure the behaviors, these systems prevent participants to talk in a natural way. In this study, we propose a software application program to automatically analyze behaviors of the participants including utterances, facial expressions (happy or neutral), head nods, and poses using only a single omnidirectional camera. The camera is small enough to be embedded into a table to allow participants to have spontaneous conversation. The proposed software utilizes facial feature tracking based on constrained local model to observe the changes of the facial features captured by the camera, and the Japanese female facial expression database to recognize expressions. Our experiment results show that there are significant correlations between measurements observed by the observers and by the software.

Auto-flotation of heterocyst enables the efficient production of renewable energy in cyanobacteria.

PubMed

Chen, Ming; Li, Jihong; Zhang, Lei; Chang, Sandra; Liu, Chen; Wang, Jianlong; Li, Shizhong

2014-02-06

Utilizing cyanobacteria as a bioenergy resource is difficult due to the cost and energy consuming harvests of microalgal biomass. In this study, an auto-floating system was developed by increasing the photobiological H2 production in the heterocysts of filamentous cyanobacteria. An amount of 1.0 μM of diuron, which inhibited O2 production in cyanobacteria, resulted in a high rate of H2 production in heterocysts. The auto-floating process recovered 91.71% ± 1.22 of the accumulated microalgal biomass from the liquid media. Quantification analysis revealed that 0.72-1.10 μmol H2 per mg dry weight microalgal biomass was necessary to create this auto-floating system. Further bio-conversion by using anaerobic digestion converted the harvested microalgal biomass into biogas. Through this novel coupled system of photobiological H2 production and anaerobic digestion, a high level of light energy conversion efficiency from solar energy to bioenergy was attained with the values of 3.79% ± 0.76.

Methods for the photochemical utilization of solar energy

NASA Technical Reports Server (NTRS)

Schwerzel, R. E.

1978-01-01

The paper considers the 'ground rules' which govern the efficiency of photochemical solar energy conversion and then summarizes the most promising approaches in each of three categories: photochemically assisted thermal systems for the heating and/or cooling of structures; photogalvanic systems for the production of electrical power in applications, such as photorechargeable batteries or inexpensive 'solar cells'; and photochemical formation of fuels for combustion and for use as chemical feedstocks or foods. Three concepts for the photochemical utilization of solar energy in space are found to be particularly promising: (1) photochemical trans-cis isomerization of indigold dyes for photoassisted heating or cooling, (2) the redox stabilized photoelectrolysis cell for the production of hydrogen (and/or oxygen or other useful chemicals), and (3) the liquid-junction photovoltaic cell for the production of electrical power.

Robust fault detection of wind energy conversion systems based on dynamic neural networks.

PubMed

Talebi, Nasser; Sadrnia, Mohammad Ali; Darabi, Ahmad

2014-01-01

Occurrence of faults in wind energy conversion systems (WECSs) is inevitable. In order to detect the occurred faults at the appropriate time, avoid heavy economic losses, ensure safe system operation, prevent damage to adjacent relevant systems, and facilitate timely repair of failed components; a fault detection system (FDS) is required. Recurrent neural networks (RNNs) have gained a noticeable position in FDSs and they have been widely used for modeling of complex dynamical systems. One method for designing an FDS is to prepare a dynamic neural model emulating the normal system behavior. By comparing the outputs of the real system and neural model, incidence of the faults can be identified. In this paper, by utilizing a comprehensive dynamic model which contains both mechanical and electrical components of the WECS, an FDS is suggested using dynamic RNNs. The presented FDS detects faults of the generator's angular velocity sensor, pitch angle sensors, and pitch actuators. Robustness of the FDS is achieved by employing an adaptive threshold. Simulation results show that the proposed scheme is capable to detect the faults shortly and it has very low false and missed alarms rate.

Robust Fault Detection of Wind Energy Conversion Systems Based on Dynamic Neural Networks

PubMed Central

Talebi, Nasser; Sadrnia, Mohammad Ali; Darabi, Ahmad

2014-01-01

Occurrence of faults in wind energy conversion systems (WECSs) is inevitable. In order to detect the occurred faults at the appropriate time, avoid heavy economic losses, ensure safe system operation, prevent damage to adjacent relevant systems, and facilitate timely repair of failed components; a fault detection system (FDS) is required. Recurrent neural networks (RNNs) have gained a noticeable position in FDSs and they have been widely used for modeling of complex dynamical systems. One method for designing an FDS is to prepare a dynamic neural model emulating the normal system behavior. By comparing the outputs of the real system and neural model, incidence of the faults can be identified. In this paper, by utilizing a comprehensive dynamic model which contains both mechanical and electrical components of the WECS, an FDS is suggested using dynamic RNNs. The presented FDS detects faults of the generator's angular velocity sensor, pitch angle sensors, and pitch actuators. Robustness of the FDS is achieved by employing an adaptive threshold. Simulation results show that the proposed scheme is capable to detect the faults shortly and it has very low false and missed alarms rate. PMID:24744774

Teaching Conversation with Trivia.

ERIC Educational Resources Information Center

Crawford, Michael J.

2002-01-01

Presents a rationale for utilizing trivia to teach conversation. Shows how trivia-based materials fit into communicative language teaching approaches and provides examples of trivia-based activities and explains how to use them in the classroom. (Author/VWL)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Eric C.D.

This paper presents a comparative techno-economic analysis of four emerging conversion pathways from biomass to gasoline-, jet-, and diesel-range hydrocarbons via indirect liquefaction with specific focus on pathways utilizing oxygenated intermediates. The processing steps include: biomass-to-syngas via indirect gasification, gas cleanup, conversion of syngas to alcohols/oxygenates followed by conversion of alcohols/oxygenates to hydrocarbon blendstocks via dehydration, oligomerization, and hydrogenation.

Hydroacylation of 2-vinyl benzaldehyde systems: an efficient method for the synthesis of chiral 3-substituted indanones.

PubMed

Kundu, Kousik; McCullagh, James V; Morehead, Andrew T

2005-11-23

Asymmetric rhodium-catalyzed hydroacylation has been utilized in the synthesis of 3-substituted indanones with high conversions and enantioselectivity. The hydroacylation reaction of 2-vinyl benzaldehyde had been previously reported to give a low yield of indanone and an unidentified product. We have identified this compound as a dimer of the starting material. Substitution at the alpha-position of the 2-vinyl benzaldehyde substrates blocks the competitive dimerization reaction and allows the reaction to proceed with yields generally greater than 90%. Utilization of BINAP as a chiral ligand results in good chemical yields and enantioselectivity greater than 95% in most cases.

Gas Conversion Systems Reclaim Fuel for Industry

NASA Technical Reports Server (NTRS)

2015-01-01

A human trip to Mars will require astronauts to utilize resources on the Red Planet to generate oxygen and fuel for the ride home, among other things. Lakewood, Colorado-based Pioneer Energy has worked under SBIR agreements with Johnson Space Center to develop technology for those purposes, and now uses a commercialized version of the technology to recover oil and gas that would otherwise be wasted at drilling sites.

Investigations of equatorial ionosphere nighttime mode conversion at VLF

NASA Astrophysics Data System (ADS)

Hildebrand, Verne

1993-05-01

VLF Radiowave propagation provides one of the few viable tools for exploring the properties of the lower D-region ionosphere. Conversely, VLF communications coverage analysis and prediction is directly dependent on the quality of models for the D-region ionosphere. The VLF Omega navigation signals are an excellent and under-utilized resource for conducting D-region research in direct support of VLF communications. Stations are well placed for investigating polar, mid latitude, and equatorial phenomena. Much can be learned by fully utilizing the very stable signals radiated at five frequencies, available from each of the eight transmitters, and taking full advantage of modal structure. While the Omega signals, 10.2 to 13.6 kHz, are well below the VLF communications band, we contend that much of the knowledge gained on D-region characteristics can be directly applied at the higher frequencies. The opportunity offered by Omega needs to be exploited. With the Global Positioning System (GPS) coming onboard as the prime means for global navigation, pressure is mounting to phase out Omega. In this paper we describe how we are using Omega along with computer codes of full wave VLF propagation, provided to us by the U.S. Naval Ocean Systems Center (NOSC), for ionosphere research and by example illustrate the potential for other investigations.

An Innovation for the Energy Industry

NASA Technical Reports Server (NTRS)

1985-01-01

REDOX is an economical energy storage system which promises major reductions in the cost of storing electrical energy. The system is based upon the conversion of chemical energy into electrical energy. 75 percent of the energy used to charge the system is returned. It is flexible and the energy may be stored for long periods. It was developed by Lewis Research Center, who transferred the technology to SOHIO for further development and possible commercialization. Redox could eliminate the use of high quality generator levels and would be particularly valuable to utilities which generate power from coal or nuclear energy.

Space power system utilizing Fresnel lenses for solar power and also thermal energy storage

NASA Technical Reports Server (NTRS)

Turner, R. H.

1983-01-01

A solar power plant suitable for earth orbits passing through Van Allen radiation belts is described. The solar-to-electricity conversion efficiency is estimated to be around 9 percent, and the expected power-to-weight ratio is competitive with photovoltaic arrays. The system is designed to be self-contained, to be indifferent to radiation belt exposures, store energy for periods when the orbiting system is in earth shadow (so that power generation is contant), have no moving parts and no working fluids, and be robust against micrometeorite attack. No electrical batteries are required.

Design of a photovoltaic system for a southwest all-electric residence

NASA Astrophysics Data System (ADS)

Mehalick, E. M.; Obrien, G.; Tully, G. F.; Johnson, J.; Parker, J.

1980-04-01

The grid connected residential photovoltaic system for the Southwest is designed to meet both space conditioning requirements and all conventional electrical load requirements for an all-electric residence. The system is comprised of two major subsystems, the solar array and the power conditioning subsystem (PCS). An 8 kW peak photovoltaic array been designed for the house. The 93 square meters solar array uses a shingle solar cell module in a highly redundant series/parallel matrix. The photovoltaic generated power is supplied to a 10kVA power conversion subsystem which is controlled to track the solar array maximum power operating point and feed the 240 Vac output power directly to the house loads or back to the utility when excess power is generated. The photovoltaic power is isolated from the utility by a 15 kVA transformer. The house design and subsystem specifications are given in detail.

Preliminary System Analysis of In Situ Resource Utilization for Mars Human Exploration

NASA Technical Reports Server (NTRS)

Rapp, Donald; Andringa, Jason; Easter, Robert; Smith, Jeffrey H .; Wilson, Thomas; Clark, D. Larry; Payne, Kevin

2005-01-01

We carried out a system analysis of processes for utilization of Mars resources to support human exploration of Mars by production of propellants from indigenous resources. Seven ISRU processes were analyzed to determine mass. power and propellant storage volume requirements. The major elements of each process include C02 acquisition, chemical conversion, and storage of propellants. Based on a figure of merit (the ratio of the mass of propellants that must be brought from Earth in a non-ISRU mission to the mass of the ISRU system. tanks and feedstocks that must be brought from Earth for a ISRU mission) the most attractive process (by far); is one where indigenous Mars water is accessible and this is processed via Sabatier/Electrolysis to methane and oxygen. These processes are technically relatively mature. Other processes with positive leverage involve reverse water gas shift and solid oxide electrolysis.

Fuel cell systems program plan, FY 1990

NASA Astrophysics Data System (ADS)

1989-10-01

A principal goal of the Office of Fossil Energy is to increase the utilization of domestic fuels in an environmentally benign manner, through the development and transfer to the private sector of advanced energy conversion technology. Successful efforts to achieve this goal contribute to the stability and reliability of reasonably priced energy supplies, enhance the competitiveness of domestic fuels and energy technologies in domestic and international markets, and contribute to the development of cost effective strategies for control of acid rain and global warming. Several advanced energy conversion technologies are now under development by DOE which can help to achieve these objectives. Fuel cells are among those technologies. This report briefly describes fuel cell technology and the program plan of U.S. DOE fuel cell program.

All silicon electrode photocapacitor for integrated energy storage and conversion.

PubMed

Cohn, Adam P; Erwin, William R; Share, Keith; Oakes, Landon; Westover, Andrew S; Carter, Rachel E; Bardhan, Rizia; Pint, Cary L

2015-04-08

We demonstrate a simple wafer-scale process by which an individual silicon wafer can be processed into a multifunctional platform where one side is adapted to replace platinum and enable triiodide reduction in a dye-sensitized solar cell and the other side provides on-board charge storage as an electrochemical supercapacitor. This builds upon electrochemical fabrication of dual-sided porous silicon and subsequent carbon surface passivation for silicon electrochemical stability. The utilization of this silicon multifunctional platform as a combined energy storage and conversion system yields a total device efficiency of 2.1%, where the high frequency discharge capability of the integrated supercapacitor gives promise for dynamic load-leveling operations to overcome current and voltage fluctuations during solar energy harvesting.

Distracted driving and associated crash risks : tech summary.

DOT National Transportation Integrated Search

2014-10-01

The main goal of this research was to utilize a driving simulator to measure the risks associated with three distractions that are routinely faced by the driving population: handheld phone conversation, texting, and front-seat passenger conversation....

Surface Tension Mediated Conversion of Light to Work

PubMed Central

Okawa, David; Pastine, Stefan J.; Zettl, Alex; Fréchet, Jean M. J.

2009-01-01

As energy demands increase, new, more direct, energy collection and utilization processes must be explored. We present a system that intrinsically combines the absorption of sunlight with the production of useful work in the form of locomotion of objects on liquids. Focused sunlight is locally absorbed by a nanostructured composite, creating a thermal surface tension gradient and, subsequently, motion. Controlled linear motion and rotational motion are demonstrated. The system is scale independent, with remotely powered and controlled motion shown for objects in the milligram to tens of grams range. PMID:20560635

Fusion of PAN and multispectral remote sensing images in shearlet domain by considering regional metrics

NASA Astrophysics Data System (ADS)

Poobalasubramanian, Mangalraj; Agrawal, Anupam

2016-10-01

The presented work proposes fusion of panchromatic and multispectral images in a shearlet domain. The proposed fusion rules rely on the regional considerations which makes the system efficient in terms of spatial enhancement. The luminance hue saturation-based color conversion system is utilized to avoid spectral distortions. The proposed fusion method is tested on Worldview2 and Ikonos datasets, and the proposed method is compared against other methodologies. The proposed fusion method performs well against the other compared methods in terms of subjective and objective evaluations.

Catalysts and process for liquid hydrocarbon fuel production

DOEpatents

White, Mark G; Liu, Shetian

2014-12-09

The present invention provides a novel process and system in which a mixture of carbon monoxide and hydrogen synthesis gas, or syngas, is converted into hydrocarbon mixtures composed of high quality gasoline components, aromatic compounds, and lower molecular weight gaseous olefins in one reactor or step. The invention utilizes a novel molybdenum-zeolite catalyst in high pressure hydrogen for conversion, as well as a novel rhenium-zeolite catalyst in place of the molybdenum-zeolite catalyst, and provides for use of the novel catalysts in the process and system of the invention.

High altitude airship configuration and power technology and method for operation of same

NASA Technical Reports Server (NTRS)

Choi, Sang H. (Inventor); Elliott, Jr., James R. (Inventor); King, Glen C. (Inventor); Park, Yeonjoon (Inventor); Kim, Jae-Woo (Inventor); Chu, Sang-Hyon (Inventor)

2011-01-01

A new High Altitude Airship (HAA) capable of various extended applications and mission scenarios utilizing inventive onboard energy harvesting and power distribution systems. The power technology comprises an advanced thermoelectric (ATE) thermal energy conversion system. The high efficiency of multiple stages of ATE materials in a tandem mode, each suited for best performance within a particular temperature range, permits the ATE system to generate a high quantity of harvested energy for the extended mission scenarios. When the figure of merit 5 is considered, the cascaded efficiency of the three-stage ATE system approaches an efficiency greater than 60 percent.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Eric; Talmadge, M.; Dutta, Abhijit

The U.S. Department of Energy (DOE) promotes research for enabling cost-competitive liquid fuels production from lignocellulosic biomass feedstocks. The research is geared to advance the state of technology (SOT) of biomass feedstock supply and logistics, conversion, and overall system sustainability. As part of their involvement in this program, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) investigate the economics of conversion pathways through the development of conceptual biorefinery process models. This report describes in detail one potential conversion process for the production of high octane gasoline blendstock via indirect liquefaction (IDL). The steps involve themore » conversion of biomass to syngas via indirect gasification followed by gas cleanup and catalytic syngas conversion to a methanol intermediate; methanol is then further catalytically converted to high octane hydrocarbons. The conversion process model leverages technologies previously advanced by research funded by the Bioenergy Technologies Office (BETO) and demonstrated in 2012 with the production of mixed alcohols from biomass. Biomass-derived syngas cleanup via tar and hydrocarbons reforming was one of the key technology advancements as part of that research. The process described in this report evaluates a new technology area with downstream utilization of clean biomass-syngas for the production of high octane hydrocarbon products through a methanol intermediate, i.e., dehydration of methanol to dimethyl ether (DME) which subsequently undergoes homologation to high octane hydrocarbon products.« less

Biotransformation of ferulic acid to protocatechuic acid by Corynebacterium glutamicum ATCC 21420 engineered to express vanillate O-demethylase.

PubMed

Okai, Naoko; Masuda, Takaya; Takeshima, Yasunobu; Tanaka, Kosei; Yoshida, Ken-Ichi; Miyamoto, Masanori; Ogino, Chiaki; Kondo, Akihiko

2017-12-01

Ferulic acid (4-hydroxy-3-methoxycinnamic acid, FA) is a lignin-derived phenolic compound abundant in plant biomass. The utilization of FA and its conversion to valuable compounds is desired. Protocatechuic acid (3,4-dihydroxybenzoic acid, PCA) is a precursor of polymers and plastics and a constituent of food. A microbial conversion system to produce PCA from FA was developed in this study using a PCA-producing strain of Corynebacterium glutamicum F (ATCC 21420). C. glutamicum strain F grown at 30 °C for 48 h utilized 2 mM each of FA and vanillic acid (4-hydroxy-3-methoxybenzoic acid, VA) to produce PCA, which was secreted into the medium. FA may be catabolized by C. glutamicum through proposed (I) non-β-oxidative, CoA-dependent or (II) β-oxidative, CoA-dependent phenylpropanoid pathways. The conversion of VA to PCA is the last step in each pathway. Therefore, the vanillate O-demethylase gene (vanAB) from Corynebacterium efficiens NBRC 100395 was expressed in C. glutamicum F (designated strain FVan) cultured at 30 °C in AF medium containing FA. Strain C. glutamicum FVan converted 4.57 ± 0.07 mM of FA into 2.87 ± 0.01 mM PCA after 48 h with yields of 62.8% (mol/mol), and 6.91 mM (1064 mg/L) of PCA was produced from 16.0 mM of FA after 12 h of fed-batch biotransformation. Genomic analysis of C. glutamicum ATCC 21420 revealed that the PCA-utilization genes (pca cluster) were conserved in strain ATCC 21420 and that mutations were present in the PCA importer gene pcaK.

Wind-assist irrigation and electrical-power generation

NASA Astrophysics Data System (ADS)

Nelson, V.; Starcher, K.

1982-07-01

A wind turbine is mechanically connected to an existing irrigation well. The system can be operated in three modes: electric motor driving the water turbine pump. Wind assist mode where wind turbine supplements power from the utility line to drive the water turbine pump. At wind speeds of 12 m/s and greater, the wind turbine can pump water (15 kW) and feed power (10 kW) back into the utility grid at the same time. Electrical generation mode where the water pump is disconnected and all power is fed back to the utility grid. The concept is technically viable as the mechanical connection allows for a smooth transfer of power in parallel with an existing power source. Minor problems caused delays and major problems of two rotor failures precluded enough operation time to obtain a good estimation of the economics. Because reliability and maintenance are difficult problems with prototype or limited production wind energy conversion systems, the expense of the demonstration project has exceeded the estimated cost by a large amount.

High-Efficiency Solar Thermal Vacuum Demonstration Completed for Refractive Secondary Concentrator

NASA Technical Reports Server (NTRS)

Wong, Wayne A.

2001-01-01

Common to many of the space applications that utilize solar thermal energy--such as electric power conversion, thermal propulsion, and furnaces--is a need for highly efficient, solar concentration systems. An effort is underway at the NASA Glenn Research Center to develop the refractive secondary concentrator, which uses refraction and total internal reflection to efficiently concentrate and direct solar energy. When used in combination with advanced lightweight primary concentrators, the refractive secondary concentrator enables very high system concentration ratios (10,000 to 1) and very high temperatures (>2000 K). The innovative refractive secondary concentrator offers significant advantages over all other types of secondary concentrators. The refractive secondary offers the highest throughput efficiency, provides for flux tailoring, requires no active cooling, relaxes the pointing and tracking requirements of the primary concentrator, and enables very high system concentration ratios. This technology has broad applicability to any system that requires the conversion of solar energy to heat. Glenn initiated the development of the refractive secondary concentrator in support of Shooting Star, a solar thermal propulsion flight experiment, and continued the development in support of Space Solar Power.

Proceedings: 1990 fossil plant cycling conference

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-12-01

Fossil plant cycling continues to be a key issue for many electric utilities. EPRI's previous cycling workshops, held in 1983, 1985, and 1987, allowed utilities to benefit from collective industry experience in the conversion of baseload fossil units to cyclic operation. Continued improvements in equipment, retrofits, diagnostics, and controls were highlighted at the 1990 conference. The objective is to provide a forum for utility discussions of the cycling operation of fossil fuel power plants. Potomac Electric Power Company (PEPCO) hosted the 1990 EPRI Fossil Fuel Cycling Conference in Washington, DC, on December 4--6, 1990. More than 130 representatives from utilities,more » vendors, government agencies, universities, and industry associations attended the conference. Following the general session, technical sessions covered such topics as plant modifications, utility retrofit experience, cycling economics, life assessment, controls, environmental controls, and energy storage. Attendees also toured PEPCO's Potomac River generating station, the site of an earlier EPRI cycling conversion study.« less

Genome-Scale Metabolic Reconstructions and Theoretical Investigation of Methane Conversion in Methylomicrobium buryatense Strain 5G(B1)

DOE PAGES

de la Torre, Andrea; Metivier, Aisha; Chu, Frances; ...

2015-11-25

Methane-utilizing bacteria (methanotrophs) are capable of growth on methane and are attractive systems for bio-catalysis. However, the application of natural methanotrophic strains to large-scale production of value-added chemicals/biofuels requires a number of physiological and genetic alterations. An accurate metabolic model coupled with flux balance analysis can provide a solid interpretative framework for experimental data analyses and integration.

A Real Options Method for Estimating the Adoption Potential of Forestry and Agroforestry Systems on Private Lands in the Lower Mississippi Alluvial Valley, USA

Treesearch

Gregory E. Frey; D. Evan Mercer; Frederick W. Cubbage; Robert C. Abt

2010-01-01

The Lower Mississippi River Alluvial Valley (LMAV), once was the largest forested bottom-land area in the continental United States, but has undergone widespread loss of forest through conversion to farmland. Restoration of forest functions and values has been a key conservation goal in the LMAV since the 1970s. This study utilizes a partial differential real options...

Energy and economic analysis of total energy systems for residential and commercial buildings. [utilizing waste heat recovery techniques

NASA Technical Reports Server (NTRS)

Maag, W. L.; Bollenbacher, G.

1974-01-01

Energy and economic analyses were performed for an on-site power-plant with waste heat recovery. The results show that for any specific application there is a characteristic power conversion efficiency that minimizes fuel consumption, and that efficiencies greater than this do not significantly improve fuel consumption. This type of powerplant appears to be a reasonably attractive investment if higher fuel costs continue.

Defense Conversion Redirecting R and D

DTIC Science & Technology

1993-05-01

agree that maglev or high members aerospace companies, utilities, univer- speed rail systems are probably limited to a few sities, small high tech...200 years. Even maglev a 3-year period for France’s TGV with a manufac- trains, long the favorite technology of the future turing workforce for the...population density. Maglev might parts of the United States, but on the basis of the contribute to the advance of some technologies, preliminary

Nonreciprocal State Conversion between Microwave and Optical Photons

NASA Astrophysics Data System (ADS)

Tian, Lin; Li, Zhen

Nonreciprocal devices are of critical importance in the realization of noiseless and lossless quantum networks. Despite previous efforts, it is still challenging to implement nonreciprocal devices that connect distinctively different frequency scales. Optomechanical quantum interfaces can be utilized to connect systems with different frequencies in hybrid quantum networks. Here we present a scheme of nonreciprocal quantum state conversion between microwave and optical photons via an optomechanical interface. By introducing an auxiliary cavity and manipulating the phase differences between the linearized optomechanical couplings, uni-directional state transmission can be achieved. The interface can function as an isolator, a circulator, and a two-way switch that routes the input states to a selected output channel. We show that under a generalized impedance matching condition, the state conversion can reach high fidelity and is robust against the thermal fluctuations in the mechanical mode. This work is supported by the National Science Foundation under Award Number 0956064. Z. Li is also supported by a fellowship from the China Scholarship Council.

Image Format Conversion to DICOM and Lookup Table Conversion to Presentation Value of the Japanese Society of Radiological Technology (JSRT) Standard Digital Image Database.

PubMed

Yanagita, Satoshi; Imahana, Masato; Suwa, Kazuaki; Sugimura, Hitomi; Nishiki, Masayuki

2016-01-01

Japanese Society of Radiological Technology (JSRT) standard digital image database contains many useful cases of chest X-ray images, and has been used in many state-of-the-art researches. However, the pixel values of all the images are simply digitized as relative density values by utilizing a scanned film digitizer. As a result, the pixel values are completely different from the standardized display system input value of digital imaging and communications in medicine (DICOM), called presentation value (P-value), which can maintain a visual consistency when observing images using different display luminance. Therefore, we converted all the images from JSRT standard digital image database to DICOM format followed by the conversion of the pixel values to P-value using an original program developed by ourselves. Consequently, JSRT standard digital image database has been modified so that the visual consistency of images is maintained among different luminance displays.

Systems definition space-based power conversion systems. [for satellite power transmission to earth

NASA Technical Reports Server (NTRS)

1976-01-01

Potential space-located systems for the generation of electrical power for use on Earth are discussed and include: (1) systems producing electrical power from solar energy; (2) systems producing electrical power from nuclear reactors; and (3) systems for augmenting ground-based solar power plants by orbital sunlight reflectors. Systems (1) and (2) would utilize a microwave beam system to transmit their output to Earth. Configurations implementing these concepts were developed through an optimization process intended to yield the lowest cost for each. A complete program was developed for each concept, identifying required production rates, quantities of launches, required facilities, etc. Each program was costed in order to provide the electric power cost appropriate to each concept.

Geothermal materials development

NASA Astrophysics Data System (ADS)

Kukacka, L. E.

1991-12-01

Advances in the development of new materials, the commercial availabilities of which are essential for the attainment of Hydrothermal Category Level 1 and 2 Objectives, continue to be made in the Geothermal Materials Development Project. Many successes have already been accrued and the results used commercially. In FY-91, utility company sponsored 'full cost' recovery programs based upon materials technology developed in this project were initiated on topics such as condensing heat exchangers, high temperature composites for utility vaults used in district heating systems, and corrosion resistant coatings for use in oil-fired electric generating processes. In FY-91, the DOE/GD-sponsored R&D project was focused on reducing well drilling, fluid transport and energy conversion costs. Specific activities being performed included lightweight CO2-resistant well cements, chemical systems for lost circulation control, thermally conductive and scale resistant protective linear systems, corrosion mitigation in process components at The Geysers, and elastomer-metal bonding systems needed for use in high temperature well drilling and safety related applications.

High Intensity Laser Power Beaming Architecture for Space and Terrestrial Missions

NASA Technical Reports Server (NTRS)

Nayfeh, Taysir; Fast, Brian; Raible, Daniel; Dinca, Dragos; Tollis, Nick; Jalics, Andrew

2011-01-01

High Intensity Laser Power Beaming (HILPB) has been developed as a technique to achieve Wireless Power Transmission (WPT) for both space and terrestrial applications. In this paper, the system architecture and hardware results for a terrestrial application of HILPB are presented. These results demonstrate continuous conversion of high intensity optical energy at near-IR wavelengths directly to electrical energy at output power levels as high as 6.24 W from the single cell 0.8 cm2 aperture receiver. These results are scalable, and may be realized by implementing receiver arraying and utilizing higher power source lasers. This type of system would enable long range optical refueling of electric platforms, such as MUAV s, airships, robotic exploration missions and provide power to spacecraft platforms which may utilize it to drive electric means of propulsion.

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

The original concept envisioned for the use of Fischer-Tropsch processing (FTP) of United States associated natural gas in this study was to provide a way of utilizing gas which could not be brought to market because a pipeline was not available or for which there was no local use. Conversion of gas by FTP could provide a means of utilizing offshore associated gas which would not require installation of a pipeline or re-injection. The premium quality F-T hydrocarbons produced by conversion of the gas can be transported in the same way as the crude oil or in combination (blended) withmore » it, eliminating the need for a separate gas transport system. FTP will produce a synthetic crude oil, thus increasing the effective size of the resource. The two conventional approaches currently used in US territory for handling of natural gas associated with crude petroleum production are re-injection and pipelining. Conversion of natural gas to a liquid product which can be transported to shore by tanker can be accomplished by FTP to produce hydrocarbons, or by conversion to chemical products such as methanol or ammonia, or by cryogenic liquefaction (LNG). This study considers FTP and briefly compares it to methanol and LNG. The Energy International Corporation cobalt catalyst, ratio adjusted, slurry bubble column F-T process was used as the basis for the study and the comparisons. An offshore F-T plant can best be accommodated by an FPSO (Floating Production, Storage, Offloading vessel) based on a converted surplus tanker, such as have been frequently used around the world recently. Other structure types used in deep water (platforms) are more expensive and cannot handle the required load.« less

Considerations in pharmaceutical conversion: focus on antihistamines.

PubMed

Garbus, S B; Moulton, B W; Meltzer, E O; Reich, P R; Weinreb, L F; Friedman, J A; Orland, B I

1997-04-01

The practice of pharmaceutical conversion, which encompasses three types of drug interchange (generic, brand, and therapeutic substitution), is increasing in managed care settings. Pharmaceutical conversion has numerous implications for managed care organizations, their healthcare providers, and their customers. Although drug cost may be a driving consideration in pharmaceutical conversion, a number of other considerations are of equal or greater importance in the decision-making process may affect the overall cost of patient care. Among these considerations are clinical, psychosocial, and safety issues; patient adherence; patient satisfaction; and legal implications of pharmaceutical conversion. Patient-centered care must always remain central to decisions about pharmaceutical conversion. This article discusses the issues related to, and implications of, pharmaceutical conversion utilizing the antihistamines class of drugs as the case situation.

Research opportunities to advance solar energy utilization.

PubMed

Lewis, Nathan S

2016-01-22

Major developments, as well as remaining challenges and the associated research opportunities, are evaluated for three technologically distinct approaches to solar energy utilization: solar electricity, solar thermal, and solar fuels technologies. Much progress has been made, but research opportunities are still present for all approaches. Both evolutionary and revolutionary technology development, involving foundational research, applied research, learning by doing, demonstration projects, and deployment at scale will be needed to continue this technology-innovation ecosystem. Most of the approaches still offer the potential to provide much higher efficiencies, much lower costs, improved scalability, and new functionality, relative to the embodiments of solar energy-conversion systems that have been developed to date. Copyright © 2016, American Association for the Advancement of Science.

Fluence-to-dose conversion coefficients for neutrons and protons calculated using the PHITS code and ICRP/ICRU adult reference computational phantoms.

PubMed

Sato, Tatsuhiko; Endo, Akira; Zankl, Maria; Petoussi-Henss, Nina; Niita, Koji

2009-04-07

The fluence to organ-dose and effective-dose conversion coefficients for neutrons and protons with energies up to 100 GeV was calculated using the PHITS code coupled to male and female adult reference computational phantoms, which are to be released as a common ICRP/ICRU publication. For the calculation, the radiation and tissue weighting factors, w(R) and w(T), respectively, as revised in ICRP Publication 103 were employed. The conversion coefficients for effective dose equivalents derived using the radiation quality factors of both Q(L) and Q(y) relationships were also estimated, utilizing the functions for calculating the probability densities of the absorbed dose in terms of LET (L) and lineal energy (y), respectively, implemented in PHITS. By comparing these data with the corresponding data for the effective dose, we found that the numerical compatibilities of the revised w(R) with the Q(L) and Q(y) relationships are fairly established. The calculated data of these dose conversion coefficients are indispensable for constructing the radiation protection systems based on the new recommendations given in ICRP103 for aircrews and astronauts, as well as for workers in accelerators and nuclear facilities.

Coherent conversion of the sunlight spectrum

NASA Technical Reports Server (NTRS)

Gustafson, T. K.

1982-01-01

Efforts related to the utilization of tunneling junctions for the conversion of radiative power to electrical power are reported. The theoretical foundations for these particular devices is presented along with a discussion of many of the practical problems associated with the implementation of such devices.

A study of the feasibility of directly applying gas generator systems to space shuttle mechanical functions

NASA Technical Reports Server (NTRS)

Lake, E. R.

1974-01-01

This study examined the current status and potential application of pyrotechnic gas generators and energy convertors for the space shuttle program. While most pyrotechnic devices utilize some form of linear actuation, only limited use of rotary actuators has been observed. This latter form of energy conversion, using a vane-type actuator as optimum, offers considerable potential in the area of servo, as well as non-servo systems, and capitalizes on a means of providing prolonged operating times. Pyrotechnic devices can often be shown to provide the optimum means of attaining a truly redundant back-up to a primary, non-pyrotechnic system.

Advanced Rankine and Brayton cycle power systems - Materials needs and opportunities

NASA Technical Reports Server (NTRS)

Grisaffe, S. J.; Guentert, D. C.

1974-01-01

Conceptual advanced potassium Rankine and closed Brayton power conversion cycles offer the potential for improved efficiency over steam systems through higher operating temperatures. However, for utility service of at least 100,000 hours, materials technology advances will be needed for such high temperature systems. Improved alloys and surface protection must be developed and demonstrated to resist coal combustion gases as well as potassium corrosion or helium surface degradation at high temperatures. Extensions in fabrication technology are necessary to produce large components of high temperature alloys. Long-time property data must be obtained under environments of interest to assure high component reliability.

Advanced Rankine and Brayton cycle power systems: Materials needs and opportunities

NASA Technical Reports Server (NTRS)

Grisaffe, S. J.; Guentert, D. C.

1974-01-01

Conceptual advanced potassium Rankine and closed Brayton power conversion cycles offer the potential for improved efficiency over steam systems through higher operating temperatures. However, for utility service of at least 100,000 hours, materials technology advances will be needed for such high temperature systems. Improved alloys and surface protection must be developed and demonstrated to resist coal combustion gases as well as potassium corrosion or helium surface degradation at high temperatures. Extensions in fabrication technology are necessary to produce large components of high temperature alloys. Long time property data must be obtained under environments of interest to assure high component reliability.

Solar thermal electric power plants - Their performance characteristics and total social costs

NASA Technical Reports Server (NTRS)

Caputo, R. S.; Truscello, V. C.

1976-01-01

The central receiver (power tower) concept as a thermal conversion approach to the conversion of solar energy into electricity is compared to other solar power plant designs which feature distributed solar collection and use other types of solar collector configurations. A variety of solar thermal storage concepts are discussed and their impacts on system performance are assessed. Although a good deal of quantification is possible in a comparative study, the subjective judgments carry enormous weight in a socio-economic decision, the ultimate choice of central power plant being more a social than an economic or technical decision. Major elements of the total social cost of each type of central plant are identified as utility economic costs, R&D funds, health costs, and other relevant social impacts.

Carbon-doped BN nanosheets for metal-free photoredox catalysis

PubMed Central

Huang, Caijin; Chen, Cheng; Zhang, Mingwen; Lin, Lihua; Ye, Xinxin; Lin, Sen; Antonietti, Markus; Wang, Xinchen

2015-01-01

The generation of sustainable and stable semiconductors for solar energy conversion by photoredox catalysis, for example, light-induced water splitting and carbon dioxide reduction, is a key challenge of modern materials chemistry. Here we present a simple synthesis of a ternary semiconductor, boron carbon nitride, and show that it can catalyse hydrogen or oxygen evolution from water as well as carbon dioxide reduction under visible light illumination. The ternary B–C–N alloy features a delocalized two-dimensional electron system with sp2 carbon incorporated in the h-BN lattice where the bandgap can be adjusted by the amount of incorporated carbon to produce unique functions. Such sustainable photocatalysts made of lightweight elements facilitate the innovative construction of photoredox cascades to utilize solar energy for chemical conversion. PMID:26159752

Dynamic Radioisotope Power System Development for Space Explorations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qualls, A L

Dynamic power conversion offers the potential to produce radioisotope power systems (RPS) that generate higher power outputs and utilize the Pu-238 radioisotope more efficiently than Radioisotope Thermoelectric Generators (RTG). Additionally, dynamic systems also offer the potential of producing generators with significantly reduced power degradation over the course of deep space missions so that more power will be available at the end of the mission when it is needed for both powering the science and transmitting the results. The development of dynamic generators involves addressing technical issues not typically associated with traditional thermoelectric generators. Developing long-life, robust and reliable dynamic conversionmore » technology is challenging yet essential to building a suitable generator. Considerations include working within existing handling infrastructure where possible so that development costs can be kept low and integrating dynamic generators into spacecraft, which may be more complex than integration of static systems. Methods of interfacing to and controlling a dynamic generator must be considered and new potential failure modes must be taken into account. This paper will address some of the key issues of dynamic RPS design, development and adaption.Dynamic power conversion offers the potential to produce Radioisotope Power Systems (RPS) that generate higher power outputs and utilize the available heat source plutonium fuel more efficiently than Radioisotope Thermoelectric Generators. Additionally, dynamic systems offer the potential of producing generators with significantly reduced power degradation over the course of deep space missions so that more power would be available at the end of the mission, when it is needed most for both powering science instruments and transmitting the resulting data. The development of dynamic generators involves addressing technical issues not typically associated with traditional thermoelectric generators. Developing long-life, robust, and reliable dynamic conversion technology is challenging yet essential to building a suitable flight-ready generator. Considerations include working within existing hardware-handling infrastructure, where possible, so that development costs can be kept low, and integrating dynamic generators into spacecraft, which may be more complex than integration of static thermoelectric systems. Methods of interfacing to and controlling a dynamic generator must also be considered, and new potential failure modes must be taken into account. This paper will address some of the key issues of dynamic RPS design, development, and adaption.« less

Implications of Fast Reactor Transuranic Conversion Ratio

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steven J. Piet; Edward A. Hoffman; Samuel E. Bays

2010-11-01

Theoretically, the transuranic conversion ratio (CR), i.e. the transuranic production divided by transuranic destruction, in a fast reactor can range from near zero to about 1.9, which is the average neutron yield from Pu239 minus 1. In practice, the possible range will be somewhat less. We have studied the implications of transuranic conversion ratio of 0.0 to 1.7 using the fresh and discharge fuel compositions calculated elsewhere. The corresponding fissile breeding ratio ranges from 0.2 to 1.6. The cases below CR=1 (“burners”) do not have blankets; the cases above CR=1 (“breeders”) have breeding blankets. The burnup was allowed to floatmore » while holding the maximum fluence to the cladding constant. We graph the fuel burnup and composition change. As a function of transuranic conversion ratio, we calculate and graph the heat, gamma, and neutron emission of fresh fuel; whether the material is “attractive” for direct weapon use using published criteria; the uranium utilization and rate of consumption of natural uranium; and the long-term radiotoxicity after fuel discharge. For context, other cases and analyses are included, primarily once-through light water reactor (LWR) uranium oxide fuel at 51 MWth-day/kg-iHM burnup (UOX-51). For CR<1, the heat, gamma, and neutron emission increase as material is recycled. The uranium utilization is at or below 1%, just as it is in thermal reactors as both types of reactors require continuing fissile support. For CR>1, heat, gamma, and neutron emission decrease with recycling. The uranium utilization exceeds 1%, especially as all the transuranic elements are recycled. exceeds 1%, especially as all the transuranic elements are recycled. At the system equilibrium, heat and gamma vary by somewhat over an order of magnitude as a function of CR. Isotopes that dominate heat and gamma emission are scattered throughout the actinide chain, so the modest impact of CR is unsurprising. Neutron emitters are preferentially found among the higher actinides, so the neutron emission varies much stronger with CR, about three orders of magnitude.« less

Power Conversion and Energy Storage System for a Fusion Reactor 3. Performance of Large Electric Power Equipment and Future View 3.1 Large Capacity Battery System -Sodium-Sulfur Battery-

NASA Astrophysics Data System (ADS)

Nakabayashi, Takashi

The Ford Motor Company proposed the principle of the sodium-sulfur battery based on a beta-alumina solid electrolyte in 1967. Accordingly, sodium-sulfur battery technology was initially developed primarily for electric vehicle applications. Later, the Tokyo Electric Power Company (TEPCO) selected the sodium-sulfur battery technology as the preferred system for a dispersed utility energy storage system to substitute for the pumped hydro energy storage system. NGK Insulators, Ltd. (NGK) and TEPCO have jointly carried out the development of the sodium-sulfur battery since 1984. In April 2002, TEPCO and NGK made the sodium-sulfur battery for use as an energy storage system commercially available.

Nontoxic fluorescent carbon nanodot serving as a light conversion material in plant for UV light utilization.

PubMed

Sai, Liman; Liu, Siqi; Qian, Xuexue; Yu, Yahui; Xu, Xiaofeng

2018-05-21

In this study, water-soluble fluorescent carbon nanodots (CNDs) were directly injected into the leaf of nicotiana tabacum. With the help of UV-to-blue light conversion nanomaterial, the photosynthetic rate of the leaf was improved 18% upon additional 6 W UV irradiation. The photostability and toxicity of different kinds of CNDs were discussed. The results showed that CNDs functionalized with NH 2 -groups on their surfaces could maintain good fluorescence in plant leaf, and CNDs with complex surface groups tended to have high toxicity to the plant. The NH 2 -functionalized CNDs with non-toxicity and good photostability were used as in vivo light conversion material for direct utilization of UV light in the solar energy. Copyright © 2018 Elsevier B.V. All rights reserved.

Web-Based Collaborative Publications System: R&Tserve

NASA Technical Reports Server (NTRS)

Abrams, Steve

1997-01-01

R&Tserve is a publications system based on 'commercial, off-the-shelf' (COTS) software that provides a persistent, collaborative workspace for authors and editors to support the entire publication development process from initial submission, through iterative editing in a hierarchical approval structure, and on to 'publication' on the WWW. It requires no specific knowledge of the WWW (beyond basic use) or HyperText Markup Language (HTML). Graphics and URLs are automatically supported. The system includes a transaction archive, a comments utility, help functionality, automated graphics conversion, automated table generation, and an email-based notification system. It may be configured and administered via the WWW and can support publications ranging from single page documents to multiple-volume 'tomes'.

Performance and Calibration of H2RG Detectors and SIDECAR ASICs for the RATIR Camera

NASA Technical Reports Server (NTRS)

Fox, Ori D.; Kutyrev, Alexander S.; Rapchun, David A.; Klein, Christopher R.; Butler, Nathaniel R.; Bloom, Josh; de Diego, Jos A.; Simn Farah, Alejandro D.; Gehrels, Neil A.; Georgiev, Leonid;

Methane utilization in Methylomicrobium alcaliphilum 20ZR: a systems approach.

PubMed

Akberdin, Ilya R; Thompson, Merlin; Hamilton, Richard; Desai, Nalini; Alexander, Danny; Henard, Calvin A; Guarnieri, Michael T; Kalyuzhnaya, Marina G

2018-02-06

Biological methane utilization, one of the main sinks of the greenhouse gas in nature, represents an attractive platform for production of fuels and value-added chemicals. Despite the progress made in our understanding of the individual parts of methane utilization, our knowledge of how the whole-cell metabolic network is organized and coordinated is limited. Attractive growth and methane-conversion rates, a complete and expert-annotated genome sequence, as well as large enzymatic, 13 C-labeling, and transcriptomic datasets make Methylomicrobium alcaliphilum 20Z R an exceptional model system for investigating methane utilization networks. Here we present a comprehensive metabolic framework of methane and methanol utilization in M. alcaliphilum 20Z R . A set of novel metabolic reactions governing carbon distribution across central pathways in methanotrophic bacteria was predicted by in-silico simulations and confirmed by global non-targeted metabolomics and enzymatic evidences. Our data highlight the importance of substitution of ATP-linked steps with PPi-dependent reactions and support the presence of a carbon shunt from acetyl-CoA to the pentose-phosphate pathway and highly branched TCA cycle. The diverged TCA reactions promote balance between anabolic reactions and redox demands. The computational framework of C 1 -metabolism in methanotrophic bacteria can represent an efficient tool for metabolic engineering or ecosystem modeling.

Solar Energy.

ERIC Educational Resources Information Center

Eaton, William W.

Presented is the utilization of solar radiation as an energy resource principally for the production of electricity. Included are discussions of solar thermal conversion, photovoltic conversion, wind energy, and energy from ocean temperature differences. Future solar energy plans, the role of solar energy in plant and fossil fuel production, and…

On-Site Fuel Cell Energy Systems: The U.S. Air Force Field Test Demonstration Plan.

DTIC Science & Technology

1980-12-01

Continue on reverse -, de if necessary and identify by block number) Fuel cells Cogererati on Energy conversion ABSTRACT (Continue an reverse ide If...fuel electrode, water at the oxygen electrode, and to act as a mechanical barrier between the two gases to prevent mixing and direct combustion . When the...possibility of more effective utilization of hydrocarbon fuels, especially when compared with the alternative heat engine combustion technologies. Figure 12

Photothermal conversion of CO₂ into CH₄ with H₂ over Group VIII nanocatalysts: an alternative approach for solar fuel production.

PubMed

Meng, Xianguang; Wang, Tao; Liu, Lequan; Ouyang, Shuxin; Li, Peng; Hu, Huilin; Kako, Tetsuya; Iwai, Hideo; Tanaka, Akihiro; Ye, Jinhua

2014-10-20

The photothermal conversion of CO2 provides a straightforward and effective method for the highly efficient production of solar fuels with high solar-light utilization efficiency. This is due to several crucial features of the Group VIII nanocatalysts, including effective energy utilization over the whole range of the solar spectrum, excellent photothermal performance, and unique activation abilities. Photothermal CO2 reaction rates (mol h(-1) g(-1)) that are several orders of magnitude larger than those obtained with photocatalytic methods (μmol h(-1) g(-1)) were thus achieved. It is proposed that the overall water-based CO2 conversion process can be achieved by combining light-driven H2 production from water and photothermal CO2 conversion with H2. More generally, this work suggests that traditional catalysts that are characterized by intense photoabsorption will find new applications in photo-induced green-chemistry processes. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High Temperature Raman Spectroscopy Study of the Conversion of Formate into Oxalate: Search for the Elusive CO 2 2 - Intermediate

NASA Astrophysics Data System (ADS)

Ryan, Charles; Mead, Anna; Lakkaraju, Prasad; Kaczur, Jerry; Bennett, Christopher; Dobbins, Tabbetha

Research on conversion of carbon dioxide into chemicals and fuels has the potential to address three problems of global relevance. (a) By removing carbon dioxide from the atmosphere, we are able to reduce the amount of greenhouse gases in the atmosphere, (b) by converting carbon dioxide into fuels, we are providing pathways for renewable energy sources, (c) by converting carbon dioxide into C2 and higher order compounds, and we are able to generate valuable precursors for organic synthesis. Formate salts are formed by the electrochemical reduction of carbon dioxide in aqueous media. However, in order to increase the utilization of carbon dioxide, methods need to be developed for the conversion of formate into compounds containing two carbon atoms such as oxalate or oxalic acid. Recently, we examined the thermal conversion of sodium formate into sodium oxalate utilizing a hydride ion catalyst. The proposed mechanism for this reaction involves the carbon dioxide dianion. Currently at NASA Goddard Space Flight Center.

Postextraction Separation, On-Board Storage, and Catalytic Conversion of Methane in Natural Gas: A Review.

PubMed

Saha, Dipendu; Grappe, Hippolyte A; Chakraborty, Amlan; Orkoulas, Gerassimos

2016-10-12

In today's perspective, natural gas has gained considerable attention, due to its low emission, indigenous availability, and improvement in the extraction technology. Upon extraction, it undergoes several purification protocols including dehydration, sweetening, and inert rejection. Although purification is a commercially established technology, several drawbacks of the current process provide an essential impetus for developing newer separation protocols, most importantly, adsorption and membrane separation. This Review summarizes the needs of natural gas separation, gives an overview of the current technology, and provides a detailed discussion of the progress in research on separation and purification of natural gas including the benefits and drawbacks of each of the processes. The transportation sector is another growing sector of natural gas utilization, and it requires an efficient and safe on-board storage system. Compressed natural gas (CNG) and liquefied natural gas (LNG) are the most common forms in which natural gas can be stored. Adsorbed natural gas (ANG) is an alternate storage system of natural gas, which is advantageous as compared to CNG and LNG in terms of safety and also in terms of temperature and pressure requirements. This Review provides a detailed discussion on ANG along with computation predictions. The catalytic conversion of methane to different useful chemicals including syngas, methanol, formaldehyde, dimethyl ether, heavier hydrocarbons, aromatics, and hydrogen is also reviewed. Finally, direct utilization of methane onto fuel cells is also discussed.

Reliability Assessment Approach for Stirling Convertors and Generators

NASA Technical Reports Server (NTRS)

Shah, Ashwin R.; Schreiber, Jeffrey G.; Zampino, Edward; Best, Timothy

2004-01-01

Stirling power conversion is being considered for use in a Radioisotope Power System for deep-space science missions because it offers a multifold increase in the conversion efficiency of heat to electric power. Quantifying the reliability of a Radioisotope Power System that utilizes Stirling power conversion technology is important in developing and demonstrating the capability for long-term success. A description of the Stirling power convertor is provided, along with a discussion about some of the key components. Ongoing efforts to understand component life, design variables at the component and system levels, related sources, and the nature of uncertainties is discussed. The requirement for reliability also is discussed, and some of the critical areas of concern are identified. A section on the objectives of the performance model development and a computation of reliability is included to highlight the goals of this effort. Also, a viable physics-based reliability plan to model the design-level variable uncertainties at the component and system levels is outlined, and potential benefits are elucidated. The plan involves the interaction of different disciplines, maintaining the physical and probabilistic correlations at all the levels, and a verification process based on rational short-term tests. In addition, both top-down and bottom-up coherency were maintained to follow the physics-based design process and mission requirements. The outlined reliability assessment approach provides guidelines to improve the design and identifies governing variables to achieve high reliability in the Stirling Radioisotope Generator design.

Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons: Dilute-Acid and Enzymatic Deconstruction of Biomass to Sugars and Biological Conversion of Sugars to Hydrocarbons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, R.; Tao, L.; Tan, E. C. D.

2013-10-01

This report describes one potential conversion process to hydrocarbon products by way of biological conversion of lingnocellulosic-dervied sugars. The process design converts biomass to a hydrocarbon intermediate, a free fatty acid, using dilute-acid pretreatement, enzymatic saccharification, and bioconversion. Ancillary areas--feed handling, hydrolysate conditioning, product recovery and upgrading (hydrotreating) to a final blendstock material, wastewater treatment, lignin combusion, and utilities--are also included in the design.

Control Strategies for Smoothing of Output Power of Wind Energy Conversion Systems

NASA Astrophysics Data System (ADS)

Pratap, Alok; Urasaki, Naomitsu; Senju, Tomonobu

2013-10-01

This article presents a control method for output power smoothing of a wind energy conversion system (WECS) with a permanent magnet synchronous generator (PMSG) using the inertia of wind turbine and the pitch control. The WECS used in this article adopts an AC-DC-AC converter system. The generator-side converter controls the torque of the PMSG, while the grid-side inverter controls the DC-link and grid voltages. For the generator-side converter, the torque command is determined by using the fuzzy logic. The inputs of the fuzzy logic are the operating point of the rotational speed of the PMSG and the difference between the wind turbine torque and the generator torque. By means of the proposed method, the generator torque is smoothed, and the kinetic energy stored by the inertia of the wind turbine can be utilized to smooth the output power fluctuations of the PMSG. In addition, the wind turbines shaft stress is mitigated compared to a conventional maximum power point tracking control. Effectiveness of the proposed method is verified by the numerical simulations.

High Power MPD Nuclear Electric Propulsion (NEP) for Artificial Gravity HOPE Missions to Callisto

NASA Technical Reports Server (NTRS)

McGuire, Melissa L.; Borowski, Stanley K.; Mason, Lee M.; Gilland, James

2003-01-01

This documents the results of a one-year multi-center NASA study on the prospect of sending humans to Jupiter's moon, Callisto, using an all Nuclear Electric Propulsion (NEP) space transportation system architecture with magnetoplasmadynamic (MPD) thrusters. The fission reactor system utilizes high temperature uranium dioxide (UO2) in tungsten (W) metal matrix cermet fuel and electricity is generated using advanced dynamic Brayton power conversion technology. The mission timeframe assumes on-going human Moon and Mars missions and existing space infrastructure to support launch of cargo and crewed spacecraft to Jupiter in 2041 and 2045, respectively.

[Code of civil procedure for medical workers -the essential principles of proceedings and expediting of trials-].

PubMed

Kageyama, Kyoko; Jimba, Koichi; Hashimoto, Satoru

2013-04-01

Code of civil procedure is started when a plaintiff appeals to the law. Conversely, if a suit is not appealed, it is not started. We explain the essential principles of the code of civil procedure, and present systems associated with expediting trials (a brief, preliminary oral arguments, preparatory proceedings, inquiry to opponent, organized proceedings, technical adviser system, etc.). Amendment of law is repeated for the purpose of aiming suitably expediting trials. We should utilize the present code of civil procedure suitably, and expect the quick conclusion of trials.

Down-conversion IM-DD RF photonic link utilizing MQW MZ modulator.

PubMed

Xu, Longtao; Jin, Shilei; Li, Yifei

2016-04-18

We present the first down-conversion intensity modulated-direct detection (IM-DD) RF photonic link that achieves frequency down-conversion using the nonlinear optical phase modulation inside a Mach-Zehnder (MZ) modulator. The nonlinear phase modulation is very sensitive and it can enable high RF-to-IF conversion efficiency. Furthermore, the link linearity is enhanced by canceling the nonlinear distortions from the nonlinear phase modulation and the MZ interferometer. Proof-of-concept measurement was performed. The down-conversion IM-DD link demonstrated 28dB improvement in distortion levels over that of a conventional IM-DD link using a LiNbO₃ MZ modulator.

Solar energy, its conversion and utilization

NASA Technical Reports Server (NTRS)

Farber, E. A.

1972-01-01

The work being carried out at the University of Florida Solar Energy and Energy Conversion Laboratory in converting solar energy, our only income, into other needed and useful forms of energy is described. A treatment such as this demonstrates, in proper perspective, how solar energy can benefit mankind with its many problems of shortages and pollution. Descriptions were given of the conversion processes, equipment, and performance. The testing of materials, solar water heating, space heating, cooking and baking, solar distillation, refrigeration and air-conditioning, work with the solar furnace, conversion to mechanical power, hot air engines, solar-heated sewage digestion, conversion to electricity, and other devices will be discussed.

Experimental comparison of MCFC performance using three different biogas types and methane

NASA Astrophysics Data System (ADS)

Bove, Roberto; Lunghi, Piero

Biogas recovery is an environmentally friendly and cost-effective practice that is getting consensus in both the scientific and industrial community, as the growing number of projects demonstrate. The use of fuel cells as energy conversion systems increases the conversion efficiency, as well as the environmental benefits. Molten carbonate fuel cells (MCFC) operate at a temperature of about 650 °C, thus presenting a high fuel flexibility, compared to low temperature fuel cells. Aim of the present study is to compare the performance of an MCFC single cell, fuelled with different biogas types as well as methane. The biogases considered are derived from the following processes: (1) steam gasification in an entrained flow gasifier; (2) steam gasification in a duel interconnect fluidized bed gasifier; (3) biogas from an anaerobic digestion process. The performances are evaluated for different fuel utilization and current densities. The results are an essential starting point for a complete system design and demonstration.

PubMedReco: A Real-Time Recommender System for PubMed Citations.

PubMed

Samuel, Hamman W; Zaïane, Osmar R

2017-01-01

We present a recommender system, PubMedReco, for real-time suggestions of medical articles from PubMed, a database of over 23 million medical citations. PubMedReco can recommend medical article citations while users are conversing in a synchronous communication environment such as a chat room. Normally, users would have to leave their chat interface to open a new web browser window, and formulate an appropriate search query to retrieve relevant results. PubMedReco automatically generates the search query and shows relevant citations within the same integrated user interface. PubMedReco analyzes relevant keywords associated with the conversation and uses them to search for relevant citations using the PubMed E-utilities programming interface. Our contributions include improvements to the user experience for searching PubMed from within health forums and chat rooms, and a machine learning model for identifying relevant keywords. We demonstrate the feasibility of PubMedReco using BMJ's Doc2Doc forum discussions.

A 15 kWe (nominal) solar thermal-electric power conversion concept definition study: Steam Rankin reciprocator system

NASA Technical Reports Server (NTRS)

Wingenback, W.; Carter, J., Jr.

1979-01-01

A conceptual design of a 3600 rpm reciprocation expander was developed for maximum thermal input power of 80 kW. The conceptual design covered two engine configurations; a single cylinder design for simple cycle operation and a two cylinder design for reheat cycle operation. The reheat expander contains a high pressure cylinder and a low pressure cylinder with steam being reheated to the initial inlet temperature after expansion in the high pressure cylinder. Power generation is accomplished with a three-phase induction motor coupled directly to the expander and connected electrically to the public utility power grid. The expander, generator, water pump and control system weigh 297 kg and are dish mounted. The steam condenser, water tank and accessory pumps are ground based. Maximum heat engine efficiency is 33 percent: maximum power conversion efficiency is 30 percent. Total cost is $3,307 or $138 per kW of maximum output power.

Dynamical Causal Modeling from a Quantum Dynamical Perspective

DOE Office of Scientific and Technical Information (OSTI.GOV)

Demiralp, Emre; Demiralp, Metin

Recent research suggests that any set of first order linear vector ODEs can be converted to a set of specific vector ODEs adhering to what we have called ''Quantum Harmonical Form (QHF)''. QHF has been developed using a virtual quantum multi harmonic oscillator system where mass and force constants are considered to be time variant and the Hamiltonian is defined as a conic structure over positions and momenta to conserve the Hermiticity. As described in previous works, the conversion to QHF requires the matrix coefficient of the first set of ODEs to be a normal matrix. In this paper, thismore » limitation is circumvented using a space extension approach expanding the potential applicability of this method. Overall, conversion to QHF allows the investigation of a set of ODEs using mathematical tools available to the investigation of the physical concepts underlying quantum harmonic oscillators. The utility of QHF in the context of dynamical systems and dynamical causal modeling in behavioral and cognitive neuroscience is briefly discussed.« less

Summary and evaluation of the Strategic Defense Initiative Space Power Architecture Study

NASA Technical Reports Server (NTRS)

Edenburn, M. (Editor); Smith, J. M. (Editor)

1989-01-01

The Space Power Architecture Study (SPAS) identified and evaluated power subsystem options for multimegawatt electric (MMWE) space based weapons and surveillance platforms for the Strategic Defense Initiative (SDI) applications. Steady state requirements of less than 1 MMWE are adequately covered by the SP-100 nuclear space power program and hence were not addressed in the SPAS. Four steady state power systems less than 1 MMWE were investigated with little difference between them on a mass basis. The majority of the burst power systems utilized H(2) from the weapons and were either closed (no effluent), open (effluent release) or steady state with storage (no effluent). Closed systems used nuclear or combustion heat source with thermionic, Rankine, turboalternator, fuel cell and battery conversion devices. Open systems included nuclear or combustion heat sources using turboalternator, magnetohydrodynamic, fuel cell or battery power conversion devices. The steady state systems with storage used the SP-100 or Star-M reactors as energy sources and flywheels, fuel cells or batteries to store energy for burst applications. As with other studies the open systems are by far the lightest, most compact and simplist (most reliable) systems. However, unlike other studies the SPAS studied potential platform operational problems caused by effluents or vibration.

System-Level Testing of the Advanced Stirling Radioisotope Generator Engineering Hardware

NASA Technical Reports Server (NTRS)

Chan, Jack; Wiser, Jack; Brown, Greg; Florin, Dominic; Oriti, Salvatore M.

2014-01-01

To support future NASA deep space missions, a radioisotope power system utilizing Stirling power conversion technology was under development. This development effort was performed under the joint sponsorship of the Department of Energy and NASA, until its termination at the end of 2013 due to budget constraints. The higher conversion efficiency of the Stirling cycle compared with that of the Radioisotope Thermoelectric Generators (RTGs) used in previous missions (Viking, Pioneer, Voyager, Galileo, Ulysses, Cassini, Pluto New Horizons and Mars Science Laboratory) offers the advantage of a four-fold reduction in Pu-238 fuel, thereby extending its limited domestic supply. As part of closeout activities, system-level testing of flight-like Advanced Stirling Convertors (ASCs) with a flight-like ASC Controller Unit (ACU) was performed in February 2014. This hardware is the most representative of the flight design tested to date. The test fully demonstrates the following ACU and system functionality: system startup; ASC control and operation at nominal and worst-case operating conditions; power rectification; DC output power management throughout nominal and out-of-range host voltage levels; ACU fault management, and system command / telemetry via MIL-STD 1553 bus. This testing shows the viability of such a system for future deep space missions and bolsters confidence in the maturity of the flight design.

Ammonia Generation and Utilization in a Passive SCR (TWC+SCR) System on Lean Gasoline Engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prikhodko, Vitaly Y.; James E. Parks, II; Pihl, Josh A.

Lean gasoline engines offer greater fuel economy than the common stoichiometric gasoline engine, but the current three way catalyst (TWC) on stoichiometric engines is unable to control nitrogen oxide (NOX) emissions in oxidizing exhaust. For these lean gasoline engines, lean NOX emission control is required to meet existing Tier 2 and upcoming Tier 3 emission regulations set by the U.S. Environmental Protection Agency (EPA). While urea-based selective catalytic reduction (SCR) has proven effective in controlling NOX from diesel engines, the urea storage and delivery components can add significant size and cost. As such, onboard NH 3 production via a passivemore » SCR approach is of interest. In a passive SCR system, NH 3 is generated over a close-coupled TWC during periodic slightly rich engine operation and subsequently stored on an underfloor SCR catalyst. Upon switching to lean operation, NOX passes through the TWC and is reduced by the stored NH 3 on the SCR catalyst. In this work, a passive SCR system was evaluated on a 2.0-liter BMW lean burn gasoline direct injection engine to assess NH 3 generation over a Pd-only TWC and utilization over a Cu-based SCR catalyst. System NOX reduction efficiency and fuel efficiency improvement compared to stoichiometric engine operation were measured. A feedback control strategy based on cumulative NH 3 produced by the TWC during rich operation and NOX emissions during lean operation was implemented on the engine to control lean/rich cycle timing. At an SCR average inlet temperature of 350 °C, an NH 3:NOX ratio of 1.15:1 (achieved through longer rich cycle timing) resulted in 99.7 % NOX conversion. Increasing NH 3 generation further resulted in even higher NOX conversion; however, tailpipe NH 3 emissions resulted. At higher underfloor temperatures, NH 3 oxidation over the SCR limited NH 3 availability for NOX reduction. At the engine conditions studied, greater than 99 % NOX conversion was achieved with passive SCR while delivering fuel efficiency benefits ranging between 6-11 % compared with stoichiometric operation.« less

Ferroelectric Phase Transformations for Energy Conversion and Storage Applications

NASA Astrophysics Data System (ADS)

Jo, Hwan Ryul

Ferroelectric materials possess a spontaneous polarization and actively respond to external mechanical, electrical, and thermal loads. Due to their coupled behavior, ferroelectric materials are used in products such as sensors, actuators, detectors, and transducers. However, most current applications rely on low-energy conversion that involves low magnitude fields. They utilize the low-field linear properties of ferroelectric materials (piezoelectric, pyroelectric) and do not take full advantage of the large-field nonlinear behavior (irreversible domain wall motion, phase transformations) that can occur in ferroelectric materials. When external fields exceed a certain critical level, a structural transformation of the crystal can occur. These phase transformations are accompanied by a much larger response than the linear piezoelectric and pyroelectric responses, by as much as a multiple of ten times in the magnitude. This makes the non-linear behavior in ferroelectric materials promising for energy harvesting and energy storage technologies which will benefit from large-energy conversion. Yet, the ferroelectric phase transformation behavior under large external fields have been less studied and only a few studies have been directed at utilizing this large material response in applications. This dissertation addresses the development ferroelectric phase transformation-based applications, with particular focus on the materials. Development of the ferroelectric phase transformation-based applications was approached in several steps. First, the phase transformation behavior was fully characterized and understood by measuring the phase transformation responses under mechanical, electrical, thermal, and combined loads. Once the behavior was well characterized, systems level applications were addressed. This required assessing the effect of the phase transformation behavior on system performance. The performance of ferroelectric devices is strongly dependent on material properties and phase transformation behavior which can be tailored by modifying the chemical composition, processing conditions, and the loading history (poling). This results in optimization of system performance by tailoring material properties and phase transformation behavior. This approach applied to three ferroelectric phase transformation-based applications: 1. Ferroelectric energy generation 2. Ferroelectric high-energy storage capacitor 3. Ferroelectric thermal energy harvesting. This dissertation has addressed tuning the large field properties for phase transformation-based systems.

Ammonia Generation and Utilization in a Passive SCR (TWC+SCR) System on Lean Gasoline Engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prikhodko, Vitaly Y; Parks, II, James E; Pihl, Josh A

Lean gasoline engines offer greater fuel economy than the common stoichiometric gasoline engine, but the current three-way catalyst (TWC) on stoichiometric engines is unable to control nitrogen oxide (NOX) emissions in the oxygen-rich exhaust. Thus, lean NOX emission control is required to meet existing Tier 2 and upcoming Tier 3 emission regulations set by the U.S. Environmental Protection Agency (EPA). While urea-based selective catalytic reduction (SCR) has proven effective in controlling NOX from diesel engines, the urea storage and delivery components can add significant size and cost. As such, onboard NH3 production via a passive SCR approach is of interest.more » In a passive SCR system, NH3 is generated over a close-coupled TWC during periodic slightly rich engine operation and subsequently stored on an underfloor SCR catalyst. Upon switching to lean operation, NOX passes through the TWC and is reduced by the stored NH3 on the SCR catalyst. In this work, a passive SCR system was evaluated on a 2.0-liter BMW lean burn gasoline direct injection engine to assess NH3 generation over a Pd-only TWC and utilization over a Cu-based SCR catalyst. System NOX reduction efficiency and fuel efficiency improvement compared to stoichiometric engine operation were measured. A feedback control strategy based on cumulative NH3 produced by the TWC during rich operation and NOX emissions during lean operation was implemented on the engine to control lean/rich cycle timing. 15% excess NH3 production over a 1:1 NH3:NOX ratio was required (via longer rich cycle timing) to achieve 99.7% NOX conversion at an SCR average inlet temperature of 350 C. Increasing NH3 generation further resulted in even higher NOX conversion; however, tailpipe NH3 emissions resulted. At higher temperatures, NH3 oxidation becomes important and limits NH3 availability for NOX reduction. At the engine conditions studied here, greater than 99% NOX conversion was achieved with passive SCR while delivering fuel efficiency benefits ranging between 6-11% compared with stoichiometric operation.« less

Ammonia Generation and Utilization in a Passive SCR (TWC+SCR) System on Lean Gasoline Engine

DOE PAGES

Prikhodko, Vitaly Y.; James E. Parks, II; Pihl, Josh A.; ...

2016-04-05

Lean gasoline engines offer greater fuel economy than the common stoichiometric gasoline engine, but the current three way catalyst (TWC) on stoichiometric engines is unable to control nitrogen oxide (NOX) emissions in oxidizing exhaust. For these lean gasoline engines, lean NOX emission control is required to meet existing Tier 2 and upcoming Tier 3 emission regulations set by the U.S. Environmental Protection Agency (EPA). While urea-based selective catalytic reduction (SCR) has proven effective in controlling NOX from diesel engines, the urea storage and delivery components can add significant size and cost. As such, onboard NH 3 production via a passivemore » SCR approach is of interest. In a passive SCR system, NH 3 is generated over a close-coupled TWC during periodic slightly rich engine operation and subsequently stored on an underfloor SCR catalyst. Upon switching to lean operation, NOX passes through the TWC and is reduced by the stored NH 3 on the SCR catalyst. In this work, a passive SCR system was evaluated on a 2.0-liter BMW lean burn gasoline direct injection engine to assess NH 3 generation over a Pd-only TWC and utilization over a Cu-based SCR catalyst. System NOX reduction efficiency and fuel efficiency improvement compared to stoichiometric engine operation were measured. A feedback control strategy based on cumulative NH 3 produced by the TWC during rich operation and NOX emissions during lean operation was implemented on the engine to control lean/rich cycle timing. At an SCR average inlet temperature of 350 °C, an NH 3:NOX ratio of 1.15:1 (achieved through longer rich cycle timing) resulted in 99.7 % NOX conversion. Increasing NH 3 generation further resulted in even higher NOX conversion; however, tailpipe NH 3 emissions resulted. At higher underfloor temperatures, NH 3 oxidation over the SCR limited NH 3 availability for NOX reduction. At the engine conditions studied, greater than 99 % NOX conversion was achieved with passive SCR while delivering fuel efficiency benefits ranging between 6-11 % compared with stoichiometric operation.« less

Site-Specific Management of Miscanthus Genotypes for Combustion and Anaerobic Digestion: A Comparison of Energy Yields.

PubMed

Kiesel, Andreas; Nunn, Christopher; Iqbal, Yasir; Van der Weijde, Tim; Wagner, Moritz; Özgüven, Mensure; Tarakanov, Ivan; Kalinina, Olena; Trindade, Luisa M; Clifton-Brown, John; Lewandowski, Iris

2017-01-01

In Europe, the perennial C 4 grass miscanthus is currently mainly cultivated for energy generation via combustion. In recent years, anaerobic digestion has been identified as a promising alternative utilization pathway. Anaerobic digestion produces a higher-value intermediate (biogas), which can be upgraded to biomethane, stored in the existing natural gas infrastructure and further utilized as a transport fuel or in combined heat and power plants. However, the upgrading of the solid biomass into gaseous fuel leads to conversion-related energy losses, the level of which depends on the cultivation parameters genotype, location, and harvest date. Thus, site-specific crop management needs to be adapted to the intended utilization pathway. The objectives of this paper are to quantify (i) the impact of genotype, location and harvest date on energy yields of anaerobic digestion and combustion and (ii) the conversion losses of upgrading solid biomass into biogas. For this purpose, five miscanthus genotypes (OPM 3, 6, 9, 11, 14), three cultivation locations (Adana, Moscow, Stuttgart), and up to six harvest dates (August-March) were assessed. Anaerobic digestion yielded, on average, 35% less energy than combustion. Genotype, location, and harvest date all had significant impacts on the energy yield. For both, this is determined by dry matter yield and ash content and additionally by substrate-specific methane yield for anaerobic digestion and moisture content for combustion. Averaged over all locations and genotypes, an early harvest in August led to 25% and a late harvest to 45% conversion losses. However, each utilization option has its own optimal harvest date, determined by biomass yield, biomass quality, and cutting tolerance. By applying an autumn green harvest for anaerobic digestion and a delayed harvest for combustion, the conversion-related energy loss was reduced to an average of 18%. This clearly shows that the delayed harvest required to maintain biomass quality for combustion is accompanied by high energy losses through yield reduction over winter. The pre-winter harvest applied in the biogas utilization pathway avoids these yield losses and largely compensates for the conversion-related energy losses of anaerobic digestion.

Site-Specific Management of Miscanthus Genotypes for Combustion and Anaerobic Digestion: A Comparison of Energy Yields

PubMed Central

Kiesel, Andreas; Nunn, Christopher; Iqbal, Yasir; Van der Weijde, Tim; Wagner, Moritz; Özgüven, Mensure; Tarakanov, Ivan; Kalinina, Olena; Trindade, Luisa M.; Clifton-Brown, John; Lewandowski, Iris

2017-01-01

In Europe, the perennial C4 grass miscanthus is currently mainly cultivated for energy generation via combustion. In recent years, anaerobic digestion has been identified as a promising alternative utilization pathway. Anaerobic digestion produces a higher-value intermediate (biogas), which can be upgraded to biomethane, stored in the existing natural gas infrastructure and further utilized as a transport fuel or in combined heat and power plants. However, the upgrading of the solid biomass into gaseous fuel leads to conversion-related energy losses, the level of which depends on the cultivation parameters genotype, location, and harvest date. Thus, site-specific crop management needs to be adapted to the intended utilization pathway. The objectives of this paper are to quantify (i) the impact of genotype, location and harvest date on energy yields of anaerobic digestion and combustion and (ii) the conversion losses of upgrading solid biomass into biogas. For this purpose, five miscanthus genotypes (OPM 3, 6, 9, 11, 14), three cultivation locations (Adana, Moscow, Stuttgart), and up to six harvest dates (August–March) were assessed. Anaerobic digestion yielded, on average, 35% less energy than combustion. Genotype, location, and harvest date all had significant impacts on the energy yield. For both, this is determined by dry matter yield and ash content and additionally by substrate-specific methane yield for anaerobic digestion and moisture content for combustion. Averaged over all locations and genotypes, an early harvest in August led to 25% and a late harvest to 45% conversion losses. However, each utilization option has its own optimal harvest date, determined by biomass yield, biomass quality, and cutting tolerance. By applying an autumn green harvest for anaerobic digestion and a delayed harvest for combustion, the conversion-related energy loss was reduced to an average of 18%. This clearly shows that the delayed harvest required to maintain biomass quality for combustion is accompanied by high energy losses through yield reduction over winter. The pre-winter harvest applied in the biogas utilization pathway avoids these yield losses and largely compensates for the conversion-related energy losses of anaerobic digestion. PMID:28367151

Designing of new structure PID controller of boost converter for solar photovoltaic stability

NASA Astrophysics Data System (ADS)

Shabrina, Hanifati Nur; Setiawan, Eko Adhi; Sabirin, Chip Rinaldi

2017-03-01

Nowadays, the utilization of renewable energy as the source on distributed generation system is increasing. It aims to reduce reliance and power losses from utility grid and improve power stability in near loads. One example of renewable energy technology that have been highly proven on the market is solar photovoltaic (PV). This technology converts photon from sunlight into electricity. However, the fluctuation of solar radiation that often occurs become the main problem for this system. Due to this condition, the power conversion is needed to convert the change frequently in photovoltaic panel into a stable voltage to the system. Developing control of boost converter has important role to keep ability of system stabilization. A conventional PID (Proportional, Integral, Derivative) control is mostly used to achieve this goal. In this research, a design of new structure PID controller of boost converter is offered to better optimize system stability comparing to the conventional PID. Parameters obtained from this PID structure have been successfully yield a stable boost converter output at 200 V with 10% overshoot, 1.5 seconds of settling time, and 1.5% of steady-state error.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brunett, A. J.; Fei, T.; Strons, P. S.

The Transient Reactor Test Facility (TREAT), located at Idaho National Laboratory (INL), is a test facility designed to evaluate the performance of reactor fuels and materials under transient accident conditions. The facility, an air-cooled, graphite-moderated reactor designed to utilize fuel containing high-enriched uranium (HEU), has been in non-operational standby status since 1994. Currently, in support of the missions of the Department of Energy (DOE) National Nuclear Security Administration (NNSA) Material Management and Minimization (M3) Reactor Conversion Program, a new core design is being developed for TREAT that will utilize low-enriched uranium (LEU). The primary objective of this conversion effort ismore » to design an LEU core that is capable of meeting the performance characteristics of the existing HEU core. Minimal, if any, changes are anticipated for the supporting systems (e.g. reactor trip system, filtration/cooling system, etc.); therefore, the LEU core must also be able to function with the existing supporting systems, and must also satisfy acceptable safety limits. In support of the LEU conversion effort, a range of ancillary safety analyses are required to evaluate the LEU core operation relative to that of the existing facility. These analyses cover neutronics, shielding, and thermal hydraulic topics that have been identified as having the potential to have reduced safety margins due to conversion to LEU fuel, or are required to support the required safety analyses documentation. The majority of these ancillary tasks have been identified in [1] and [2]. The purpose of this report is to document the ancillary safety analyses that have been performed at Argonne National Laboratory during the early stages of the LEU design effort, and to describe ongoing and anticipated analyses. For all analyses presented in this report, methodologies are utilized that are consistent with, or improved from, those used in analyses for the HEU Final Safety Analysis Report (FSAR) [3]. Depending on the availability of historical data derived from HEU TREAT operation, results calculated for the LEU core are compared to measurements obtained from HEU TREAT operation. While all analyses in this report are largely considered complete and have been reviewed for technical content, it is important to note that all topics will be revisited once the LEU design approaches its final stages of maturity. For most safety significant issues, it is expected that the analyses presented here will be bounding, but additional calculations will be performed as necessary to support safety analyses and safety documentation. It should also be noted that these analyses were completed as the LEU design evolved, and therefore utilized different LEU reference designs. Preliminary shielding, neutronic, and thermal hydraulic analyses have been completed and have generally demonstrated that the various LEU core designs will satisfy existing safety limits and standards also satisfied by the existing HEU core. These analyses include the assessment of the dose rate in the hodoscope room, near a loaded fuel transfer cask, above the fuel storage area, and near the HEPA filters. The potential change in the concentration of tramp uranium and change in neutron flux reaching instrumentation has also been assessed. Safety-significant thermal hydraulic items addressed in this report include thermally-induced mechanical distortion of the grid plate, and heating in the radial reflector.« less

Solar pv fed stand-alone excitation system of a synchronous machine for reactive power generation

NASA Astrophysics Data System (ADS)

Sudhakar, N.; Jain, Siddhartha; Jyotheeswara Reddy, K.

2017-11-01

This paper presents a model of a stand-alone solar energy conversion system based on synchronous machine working as a synchronous condenser in overexcited state. The proposed model consists of a Synchronous Condenser, a DC/DC boost converter whose output is fed to the field of the SC. The boost converter is supplied by the modelled solar panel and a day time variable irradiance is fed to the panel during the simulation time. The model also has one alternate source of rechargeable batteries for the time when irradiance falls below a threshold value. Also the excess power produced when there is ample irradiance is divided in two parts and one is fed to the boost converter while other is utilized to recharge the batteries. A simulation is done in MATLAB-SIMULINK and the obtained results show the utility of such modelling for supplying reactive power is feasible.

Chromatic dispersion concentrator applied to photovoltaic systems

NASA Astrophysics Data System (ADS)

Sassi, G.

1980-01-01

The aim of this paper is to show how it is possible to realize a chromatic dispersion concentrator which collects the different monochromatic components of the solar spectrum separately in subsequently concentric rings in the focal zone. This comes about without an increase in the energetic losses compared to any other type of concentrator. If different photovoltaic elements with energy gaps equal to the photon energy falling on the focal zone are put in the latter, energy losses due to incomplete utilization of the solar spectrum and to incomplete utilization of the energy of a single photon can be drastically reduced. How the losses due to the voltage factor and the fill-factor of the photovoltaic elements of the system can be reduced compared to the normal silicon cells is also demonstrated. The other contributions to losses in the conversion process have only been mentioned, foreseeing their possible variation.

Self-Biased Hybrid Piezoelectric-Photoelectrochemical Cell with Photocatalytic Functionalities.

PubMed

Tan, Chuan Fu; Ong, Wei Li; Ho, Ghim Wei

2015-07-28

Utilizing solar energy for environmental and energy remediations based on photocatalytic hydrogen (H2) generation and water cleaning poses great challenges due to inadequate visible-light power conversion, high recombination rate, and intermittent availability of solar energy. Here, we report an energy-harvesting technology that utilizes multiple energy sources for development of sustainable operation of dual photocatalytic reactions. The fabricated hybrid cell combines energy harvesting from light and vibration to run a power-free photocatalytic process that exploits novel metal-semiconductor branched heterostructure (BHS) of its visible light absorption, high charge-separation efficiency, and piezoelectric properties to overcome the aforementioned challenges. The desirable characteristics of conductive flexible piezoelectrode in conjunction with pronounced light scattering of hierarchical structure originate intrinsically from the elaborate design yet facile synthesis of BHS. This self-powered photocatalysis system could potentially be used as H2 generator and water treatment system to produce clean energy and water resources.

A Novel Multilevel DC - AC Converter from Green Energy Power Generators Using Step-Square Waving and PWM Technique

NASA Astrophysics Data System (ADS)

Fajingbesi, F. E.; Midi, N. S.; Khan, S.

2017-06-01

Green energy sources or renewable energy system generally utilize modular approach in their design. This sort of power sources are generally in DC form or in single cases AC. Due to high fluctuation in the natural origin of this energy (wind & solar) source they are stored as DC. DC power however are difficult to transfer over long distances hence DC to AC converters and storage system are very important in green energy system design. In this work we have designed a novel multilevel DC to AC converter that takes into account the modular design of green energy systems. A power conversion efficiency of 99% with reduced total harmonic distortion (THD) was recorded from our simulated system design.

Evaluation of a Digital Companion for Older Adults with Mild Cognitive Impairment

PubMed Central

Demiris, George; Thompson, Hilaire J.; Lazar, Amanda; Lin, Shih-Yin

2016-01-01

Study Objective: The purpose of this study was to examine the feasibility of a digital companion system used by older adults with mild cognitive impairment (MCI). We utilized a commercially available system that is comprehensive in its functionalities (including conversation ability, use of pictures and other media, and reminders) to explore the system’s impact on older adults ‘ social interactions, anxiety, depressive symptoms, and acceptance of the system. Study Design: We conducted a three-month mixed methods evaluation study of the digital companion. Results: Ten female community-dwelling older adults (average age 78.3 years) participated in the study. Overall, participants utilized the tool regularly and appreciated its presence and their interactions. Participants scored higher at the end of the study in cognition and social support scales, and lower in presence of depressive symptoms. Conclusion: Findings indicate the feasibility of a digital companion for people with MCI and inform the need for additional research. PMID:28269845

Induction Curing of Thiol-acrylate and Thiolene Composite Systems

PubMed Central

Ye, Sheng; Cramer, Neil B.; Stevens, Blake E.; Sani, Robert L.; Bowman, Christopher N.

2011-01-01

Induction curing is demonstrated as a novel type of in situ radiation curing that maintains most of the advantages of photocuring while eliminating the restriction of light accessibility. Induction curing is utilized to polymerize opaque composites comprised of thiol-acrylate and thiol-ene resins, nanoscale magnetic particles, and carbon nanotubes. Nanoscale magnetic particles are dispersed in the resin and upon exposure to the magnetic field, these particles lead to induction heating that rapidly initiates the polymerization. Heat transfer profiles and reaction kinetics of the samples are modeled during the reactions with varying induction heater power, species concentration, species type and sample thickness, and the model is compared with the experimental results. Thiol-ene polymerizations achieved full conversion between 1.5 minutes and 1 hour, depending on the field intensity and the composition, with the maximum reaction temperature decreasing from 146 – 87 °C when the induction heater power was decreased from 8 – 3 kW. The polymerization reactions of the thiol-acrylate system were demonstrated to achieve full conversion between 0.6 and 30 minutes with maximum temperatures from 139 to 86 °C. The experimental behavior was characterized and the temperature profile modeled for the thiol-acrylate composite comprised of sub100nm nickel particles and induction heater power in the range of 32 to 20 kW. A 9°C average deviation was observed between the modeling and experimental results for the maximum temperature rise. The model also was utilized to predict reaction temperatures and kinetics for systems with varying thermal initiator concentration, initiator half-life, monomer molecular weight and temperature gradients in samples with varying thickness, thereby demonstrating that induction curing represents a designable and tunable polymerization method. Finally, induction curing was utilized to cure thiol-acrylate systems containing carbon nanotubes where 1 wt% carbon nanotubes resulted in systems where the storage modulus increased from 17.6 ± 0.2 to 21.6 ± 0.1 MPa and an electrical conductivity that increased from <10−7 to 0.33 ± 0.5 S/m. PMID:21765552

Evaluation of Long Duration Flight on Venus

NASA Technical Reports Server (NTRS)

Landis, Geoffrey A.; Colozza, Anthony J.

2006-01-01

An analysis was performed to evaluate the potential of utilizing either an airship or aircraft as a flight platform for long duration flight within the atmosphere of Venus. In order to achieve long-duration flight, the power system for the vehicle had to be capable of operating for extended periods of time. To accomplish these, two types of power systems were considered, a solar energy-based power system utilizing a photovoltaic array as the main power source and a radioisotope heat source power system utilizing a Stirling engine as the heat conversion device. Both types of vehicles and power systems were analyzed to determine their flight altitude range. This analysis was performed for a station-keeping mission where the vehicle had to maintain a flight over a location on the ground. This requires the vehicle to be capable of flying faster than the wind speed at a particular altitude. An analysis was also performed to evaluate the altitude range and maximum duration for a vehicle that was not required to maintain station over a specified location. The results of the analysis show that each type of flight vehicle and power system was capable of flight within certain portions of Venus s atmosphere. The aircraft, both solar and radioisotope power proved to be the most versatile and provided the greatest range of coverage both for station-keeping and non-station-keeping missions.

Electron-beam lithography with character projection exposure for throughput enhancement with line-edge quality optimization

NASA Astrophysics Data System (ADS)

Ikeno, Rimon; Maruyama, Satoshi; Mita, Yoshio; Ikeda, Makoto; Asada, Kunihiro

2016-03-01

Among various electron-beam lithography (EBL) techniques, variable-shaped beam (VSB) and character projection (CP) methods have attracted many EBL users for their high-throughput feature, but they are considered to be more suited to small-featured VLSI fabrication with regularly-arranged layouts like standard-cell logics and memory arrays. On the other hand, non-VLSI applications like photonics, MEMS, MOEMS, and so on, have not been fully utilized the benefit of CP method due to their wide variety of layout patterns. In addition, the stepwise edge shapes by VSB method often causes intolerable edge roughness to degrade device characteristics from its intended performance with smooth edges. We proposed an overall EBL methodology applicable to wade-variety of EBL applications utilizing VSB and CP methods. Its key idea is in our layout data conversion algorithm that decomposes curved or oblique edges of arbitrary layout patterns into CP shots. We expect significant reduction in EB shot count with a CP-bordered exposure data compared to the corresponding VSB-alone conversion result. Several CP conversion parameters are used to optimize EB exposure throughput, edge quality, and resultant device characteristics. We demonstrated out methodology using the leading-edge VSB/CP EBL tool, ADVANTEST F7000S-VD02, with high resolution Hydrogen Silsesquioxane (HSQ) resist. Through our experiments of curved and oblique edge lithography under various data conversion conditions, we learned correspondence of the conversion parameters to the resultant edge roughness and other conditions. They will be utilized as the fundamental data for further enhancement of our EBL strategy for optimized EB exposure.

Skills Conversion Project: Chapter 2, Executive Summary. Final Report.

ERIC Educational Resources Information Center

National Society of Professional Engineers, Washington, DC.

This final report describes the Skills Conversion Project conducted by The National Society of Professional Engineers under contract to the Department of Labor to study methods of utilizing the large pool of highly skilled unemployed technicians and professional personnel who were formerly employed in the aerospace and defense industries. If…

DIRECT CONVERSION OF MUNICIPAL AND AGRICULTURAL WASTES TO BIODIESEL AND ETHANOL UTILIZING A UNIQUE EXTREMOPHILIC FUNGUS - PHASE I

EPA Science Inventory

Sustainable Bioproducts LLC’s proposed research will further develop an efficient, economical and scalable process for conversion of municipal solid wastes and agricultural wastes to biodiesel and ethanol. The technology is based on use of a novel extremophilic fun...

Biennial Wind Energy Conference and Workshop, 5th, Washington, DC, October 5-7, 1981, Proceedings

NASA Astrophysics Data System (ADS)

1982-05-01

The results of studies funded by the Federal government to advance the state of the art of wind energy conversion systems (WECS) construction, operation, applications, and financial viability are presented. The economics of WECS were considered in terms of applicable tax laws, computer simulations of net value of WECS to utilities, and the installation of Mod-2 2.5 MW and WTS-4 4MW wind turbines near Medicine Bow, WY to test the operation of two different large WECS on the same utility grid. Potential problems of increasing penetration of WECS-produced electricity on a utility grid were explored and remedies suggested. The structural dynamics of wind turbines were analyzed, along with means to predict potential noise pollution from large WECS, and to make blade fatigue life assessments. Finally, Darrieus rotor aerodynamics were investigated, as were dynamic stall in small WECS and lightning protection for wind turbines and components.

Coal conversion legislation. Part I. Hearings before the Subcommittee on Energy Production and Supply of the Committee on Energy and Natural Resources, United States Senate, Ninety-Fifth Congress, First Session on S. 272, S. 273, and S. 977, March 21 and 29, 1977. [Coal utilization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1977-01-01

The legislation on greater coal utilization before the committee includes S. 272 (requiring, to the extent practicable, electric power plants and major fuel-bearing installations to utilize fuels other than natural gas); S. 273 (requiring, to the extent practicable, new electric power plants and new major fuel-burning installations be constructed to utliize fuels other than natural gas or petroleum); and S. 977 (requiring, to the extent practicable, existing electric power plants and major fuel-burning installations to utilize fuels other than natural gas or petroleum). Statements were heard from seven senators and representatives from the following: American Electric Power Service Corp., Americanmore » Boiler Manufactures Association, National Electric Reliability Council, Virgina Electric and Power Co., Fossil Power Systems, Houston Lighting and Power Co., other electric utility industry representatives, and the Federal Energy Adminstration. Additional material from the Wall Street Journal and the Washington Post is included. (MCW)« less

Construction of cellulose-utilizing Escherichia coli based on a secretable cellulase.

PubMed

Gao, Dongfang; Luan, Yaqi; Wang, Qian; Liang, Quanfeng; Qi, Qingsheng

2015-10-09

The microbial conversion of plant biomass into value added products is an attractive option to address the impacts of petroleum dependency. The Gram-negative bacterium Escherichia coli is commonly used as host for the industrial production of various chemical products with a variety of sugars as carbon sources. However, this strain neither produces endogenous cellulose degradation enzymes nor secrets heterologous cellulases for its poor secretory capacity. Thus, a cellulolytic E. coli strain capable of growth on plant biomass would be the first step towards producing chemicals and fuels. We previously identified the catalytic domain of a cellulase (Cel-CD) and its N-terminal sequence (N20) that can serve as carriers for the efficient extracellular production of target enzymes. This finding suggested that cellulose-utilizing E. coli can be engineered with minimal heterologous enzymes. In this study, a β-glucosidase (Tfu0937) was fused to Cel-CD and its N-terminal sequence respectively to obtain E. coli strains that were able to hydrolyze the cellulose. Recombinant strains were confirmed to use the amorphous cellulose as well as cellobiose as the sole carbon source for growth. Furthermore, both strains were engineered with poly (3-hydroxybutyrate) (PHB) synthesis pathway to demonstrate the production of biodegradable polyesters directly from cellulose materials without exogenously added cellulases. The yield of PHB reached 2.57-8.23 wt% content of cell dry weight directly from amorphous cellulose/cellobiose. Moreover, we found the Cel-CD and N20 secretion system can also be used for the extracellular production of other hydrolytic enzymes. This study suggested that a cellulose-utilizing E. coli was created based on a heterologous cellulase secretion system and can be used to produce biofuels and biochemicals directly from cellulose. This system also offers a platform for conversion of other abundant renewable biomass to biofuels and biorefinery products.

Conversion rate of para-hydrogen to ortho-hydrogen by oxygen: implications for PHIP gas storage and utilization.

PubMed

Wagner, Shawn

2014-06-01

To determine the storability of para-hydrogen before reestablishment of the room temperature thermal equilibrium mixture. Para-hydrogen was produced at near 100% purity and mixed with different oxygen quantities to determine the rate of conversion to the thermal equilibrium mixture of 75: 25% (ortho: para) by detecting the ortho-hydrogen (1)H nuclear magnetic resonance using a 9.4 T imager. The para-hydrogen to ortho-hydrogen velocity constant, k, near room temperature (292 K) was determined to be 8.27 ± 1.30 L/mol · min(-1). This value was calculated utilizing four different oxygen fractions. Para-hydrogen conversion to ortho-hydrogen by oxygen can be minimized for long term storage with judicious removal of oxygen contamination. Prior calculated velocity rates were confirmed demonstrating a dependence on only the oxygen concentration.

Space Station module Power Management And Distribution (PMAD) system

NASA Technical Reports Server (NTRS)

Walls, Bryan

1990-01-01

This project consists of several tasks which are unified toward experimentally demonstrating the operation of a highly autonomous, user-supportive power management and distribution system for Space Station Freedom (SSF) habitation/laboratory modules. This goal will be extended to a demonstration of autonomous, cooperative power system operation for the whole SSF power system through a joint effort with NASA's Lewis Research Center, using their Autonomous Power System. Short term goals for the space station module power management and distribution include having an operational breadboard reflecting current plans for SSF, improving performance of the system communications, and improving the organization and mutability of the artificial intelligence (AI) systems. In the middle term, intermediate levels of autonomy will be added, user interfaces will be modified, and enhanced modeling capabilities will be integrated in the system. Long term goals involve conversion of all software into Ada, vigorous verification and validation efforts and, finally, seeing an impact of this research on the operation of SSF. Conversion of the system to a DC Star configuration is now in progress, and should be completed by the end of October, 1989. This configuration reflects the latest SSF module architecture. Hardware is now being procured which will improve system communications significantly. The Knowledge-Based Management System (KBMS) is initially developed and the rules from FRAMES have been implemented in the KBMS. Rules in the other two AI systems are also being grouped modularly, making them more tractable, and easier to eventually move into the KBMS. Adding an intermediate level of autonomy will require development of a planning utility, which will also be built using the KBMS. These changes will require having the user interface for the whole system available from one interface. An Enhanced Model will be developed, which will allow exercise of the system through the interface without requiring all of the power hardware to be operational. The functionality of the AI systems will continue to be advanced, including incipient failure detection. Ada conversion will begin with the lowest level processor (LLP) code. Then selected pieces of the higher level functionality will be recorded in Ada and, where possible, moved to the LLP level. Validation and verification will be done on the Ada code, and will complete sometimes after completion of the Ada conversion.

Constructing the electricity-carbohydrate-hydrogen cycle for a sustainability revolution.

PubMed

Zhang, Y-H Percival; Huang, Wei-Dong

2012-06-01

In this opinion, we suggest the electricity-carbohydrate-hydrogen (ECHo) cycle which bridges primary energies and secondary energies. Carbohydrates are sources of food, feed, liquid biofuels, and renewable materials and are a high-density hydrogen carrier and electricity storage compounds (e.g. >3000 Wh/kg). One element of this ECHo cycle can be converted to another reversibly and efficiently depending on resource availability, needs and costs. This cycle not only supplements current and future primary energy utilization systems for facilitating electricity and hydrogen storage and enhancing secondary energy conversion efficiencies, but also addresses such sustainability challenges as transportation fuel production, CO(2) utilization, fresh water conservation, and maintenance of a small closed ecosystem in emergency situations. Copyright © 2012 Elsevier Ltd. All rights reserved.

First North American 50 cc Total Artificial Heart Experience: Conversion from a 70 cc Total Artificial Heart.

PubMed

Khalpey, Zain; Kazui, Toshinobu; Ferng, Alice S; Connell, Alana; Tran, Phat L; Meyer, Mark; Rawashdeh, Badi; Smith, Richard G; Sweitzer, Nancy K; Friedman, Mark; Lick, Scott; Slepian, Marvin J; Copeland, Jack G

2016-01-01

The 70 cc total artificial heart (TAH) has been utilized as bridge to transplant (BTT) for biventricular failure. However, the utilization of 70 cc TAH has been limited to large patients for the low output from the pulmonary as well as systemic vein compression after chest closure. Therefore, the 50 cc TAH was developed by SynCardia (Tucson, AZ) to accommodate smaller chest cavity. We report the first TAH exchange from a 70 to 50 cc due to a fit difficulty. The patient failed to be closed with a 70 cc TAH, although the patient met the conventional 70 cc TAH fit criteria. We successfully closed the chest with a 50 cc TAH.

Development of the Contextual Assessment of Social Skills (CASS): a role play measure of social skill for individuals with high-functioning autism.

PubMed

Ratto, Allison B; Turner-Brown, Lauren; Rupp, Betty M; Mesibov, Gary B; Penn, David L

2011-09-01

This study piloted a role play assessment of conversational skills for adolescents and young adults with high-functioning autism/Asperger syndrome (HFA/AS). Participants completed two semi-structured role plays, in which social context was manipulated by changing the confederate's level of interest in the conversation. Participants' social behavior was rated via a behavioral coding system, and performance was compared across contexts and groups. An interaction effect was found for several items, whereby control participants showed significant change across context, while participants with HFA/AS showed little or no change. Total change across contexts was significantly correlated with related social constructs and significantly predicted ASD. The findings are discussed in terms of the potential utility of the CASS in the evaluation of social skill.

Homogeneous Hydrogenation of CO₂ to Methyl Formate Utilizing Switchable Ionic Liquids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yadav, Mahendra; Linehan, John C.; Karkamkar, Abhijeet J.

2014-09-15

Capture of CO₂ and subsequent hydrogenation allows for base/alcohol-catalyzed conversion of CO₂ to methylformate in one pot. The conversion of CO₂ proceeds via alkylcarbonates, to formate salts and then formate esters, which can be catalyzed by base and alcohol with the only byproduct being water. The system operates at mild conditions (300 psi H₂, 140 °C). Reactivity is strongly influenced by temperature and choice of solvent. In the presence of excess of base (DBU) formate is predominant product while in excess of methanol methyl formate is major product. 110 °C yields formate salts, 140 °C promotes methylformate. The authors acknowledgemore » internal Laboratory Directed Re-search and Development (LDRD) funding from Pacific Northwest National Laboratory (PNNL). PNNL is operated by Battelle for the U.S. Department of Energy.« less

Operando Spectroscopic Microscopy of LiCoO 2 Cathodes Outside Standard Operating Potentials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson Weker, Johanna; Wise, Anna M.; Lim, Kipil

LiCoO 2 can experience over-lithiation (over-discharge) in an electrochemical cell due to poor battery management, failure such as a short circuit, or when LiCoO 2 is utilized as a negative electrode conversion material. Furthermore, in order to understand the chemical and morphological changes which occur during over-lithiation, LiCoO 2 electrodes were studied during deep discharge to 0.8 V with operando X-ray absorption spectroscopy and spectroscopic X-ray microscopy. During over-lithiation, micron-sized LiCoO 2 particles suffer significant cracking, pulverization and an incomplete conversion to Co metal. These irreversible morphological and structural changes then inflict permanent damage on the cathode even during amore » single over-lithiation event and highlight the need for more sophisticated battery management systems.« less

Operando Spectroscopic Microscopy of LiCoO 2 Cathodes Outside Standard Operating Potentials

DOE PAGES

Nelson Weker, Johanna; Wise, Anna M.; Lim, Kipil; ...

2017-07-14

LiCoO 2 can experience over-lithiation (over-discharge) in an electrochemical cell due to poor battery management, failure such as a short circuit, or when LiCoO 2 is utilized as a negative electrode conversion material. Furthermore, in order to understand the chemical and morphological changes which occur during over-lithiation, LiCoO 2 electrodes were studied during deep discharge to 0.8 V with operando X-ray absorption spectroscopy and spectroscopic X-ray microscopy. During over-lithiation, micron-sized LiCoO 2 particles suffer significant cracking, pulverization and an incomplete conversion to Co metal. These irreversible morphological and structural changes then inflict permanent damage on the cathode even during amore » single over-lithiation event and highlight the need for more sophisticated battery management systems.« less

Ionic liquids: Promising green solvents for lignocellulosic biomass utilization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoo, Chang Geun; Pu, Yunqiao; Ragauskas, Arthur J.

Ionic liquids are effective solvents/media for the utilization of lignocellulosic biomass. The unique properties of ionic liquids enable them to effectively dissolve and/or convert the biomass into various types of products. This review aims to cover the latest progress achieved in applications of ionic liquids on biomass conversion and analysis. Specifically, several recently developed approaches on how to overcome current challenges on the use of ionic liquids in the biomass conversion were highlighted. Here, recent studies addressing the potential applications of ionic liquids for the production of novel biomass-derived chemicals and materials were also discussed.

Ionic liquids: Promising green solvents for lignocellulosic biomass utilization

DOE PAGES

Yoo, Chang Geun; Pu, Yunqiao; Ragauskas, Arthur J.

2017-06-01

Ionic liquids are effective solvents/media for the utilization of lignocellulosic biomass. The unique properties of ionic liquids enable them to effectively dissolve and/or convert the biomass into various types of products. This review aims to cover the latest progress achieved in applications of ionic liquids on biomass conversion and analysis. Specifically, several recently developed approaches on how to overcome current challenges on the use of ionic liquids in the biomass conversion were highlighted. Here, recent studies addressing the potential applications of ionic liquids for the production of novel biomass-derived chemicals and materials were also discussed.

Alternative OTEC Scheme for a Submarine Robot

NASA Technical Reports Server (NTRS)

Jones, Jack; Chao, Yi

2009-01-01

A proposed system for exploiting the ocean thermal gradient to generate power would be based on the thawing-expansion/ freezing-contraction behavior of a wax or perhaps another suitable phase-change material. The power generated by this system would be used to recharge the batteries in a battery-powered unmanned underwater vehicle [UUV (essentially, a small exploratory submarine robot)] of a type that has been deployed in large numbers in research pertaining to global warming. A UUV of this type travels between the ocean surface and various depths, measuring temperature and salinity. This proposed system would be an alternative to another proposed ocean thermal energy conversion (OTEC) system that would serve the same purpose but would utilize a thermodynamic cycle in which CO2 would be the working fluid. That system is described in Utilizing Ocean Thermal Energy in a Submarine Robot (NPO-43304), immediately following this brief. The main advantage of this proposed system over the one using CO2 is that it could derive a useful amount of energy from a significantly smaller temperature difference. At one phase of its operational cycle, the system now proposed would utilize the surface ocean temperature (which lies between 15 and 20 C over most of the Earth) to melt a wax (e.g., pentadecane) that has a melting/freezing temperature of about 10 C. At the opposite phase of its operational cycle, the system would utilize the lower ocean temperature at depth (e.g., between 4 and 7 C at a depth of 300 m) to freeze the wax. The melting or freezing causes the wax to expand or contract, respectively, by about 8 volume percent.

Treatment of natural rubber processing wastewater using a combination system of a two-stage up-flow anaerobic sludge blanket and down-flow hanging sponge system.

PubMed

Tanikawa, D; Syutsubo, K; Hatamoto, M; Fukuda, M; Takahashi, M; Choeisai, P K; Yamaguchi, T

2016-01-01

A pilot-scale experiment of natural rubber processing wastewater treatment was conducted using a combination system consisting of a two-stage up-flow anaerobic sludge blanket (UASB) and a down-flow hanging sponge (DHS) reactor for more than 10 months. The system achieved a chemical oxygen demand (COD) removal efficiency of 95.7% ± 1.3% at an organic loading rate of 0.8 kg COD/(m(3).d). Bacterial activity measurement of retained sludge from the UASB showed that sulfate-reducing bacteria (SRB), especially hydrogen-utilizing SRB, possessed high activity compared with methane-producing bacteria (MPB). Conversely, the acetate-utilizing activity of MPB was superior to SRB in the second stage of the reactor. The two-stage UASB-DHS system can reduce power consumption by 95% and excess sludge by 98%. In addition, it is possible to prevent emissions of greenhouse gases (GHG), such as methane, using this system. Furthermore, recovered methane from the two-stage UASB can completely cover the electricity needs for the operation of the two-stage UASB-DHS system, accounting for approximately 15% of the electricity used in the natural rubber manufacturing process.

Plasmon-assisted radiolytic energy conversion in aqueous solutions

PubMed Central

Kim, Baek Hyun; Kwon, Jae W.

2014-01-01

The field of conventional energy conversion using radioisotopes has almost exclusively focused on solid-state materials. Herein, we demonstrate that liquids can be an excellent media for effective energy conversion from radioisotopes. We also show that free radicals in liquid, which are continuously generated by beta radiation, can be utilized for electrical energy generation. Under beta radiation, surface plasmon obtained by the metallic nanoporous structures on TiO2 enhanced the radiolytic conversion via the efficient energy transfer between plasmons and free radicals. This work introduces a new route for the development of next-generation power sources. PMID:24918356

Technical and economic feasibility study of solar/fossil hybrid power systems

NASA Technical Reports Server (NTRS)

Bloomfield, H. S.; Calogeras, J. E.

1977-01-01

Results show that new hybrid systems utilizing fossil fuel augmentation of solar energy can provide significant capital and energy cost benefits when compared with solar thermal systems requiring thermal storage. These benefits accrue from a reduction of solar collection area that results from both the use of highly efficient gas and combined cycle energy conversion subsystems and elimination of the requirement for long-term energy storage subsystems. Technical feasibility and fuel savings benefits of solar hybrid retrofit to existing fossil-fired, gas and vapor cycle powerplants was confirmed; however, economic viability of steam cycle retrofit was found to be dependent on the thermodynamic and operational characteristics of the existing powerplant.

Influence of diet pellet hardness and particle size on food utilization by mice, rats and hamsters.

PubMed

Ford, D J

1977-10-01

Increasing hardness of diet pellets reduced food wastage by each species. Also, less wastage occurred when pellets made from finely ground materials were given, an effect that was not related to hardness. The hardest diet reduced growth of the mice by reducing true food consumption and a poorer food conversion efficiency (true food consumption/growth) was obtained. Apparent food consumption increased with the softness of the diet and food utilization (apparent food consumption/growth) of the softest diets was less efficient than those of the others. Grinding of the raw materials prior to pelleting had no effect on food conversion, but food utilization was less efficient because of the greater wastage of pellets from coarsely ground materials and consequent apparent food comsumption.

The Practical Implementation of Non-Contacting Laser Strain Measurements Systems

NASA Technical Reports Server (NTRS)

Yunis, Isam; Quinn, roger D.; Kadambi, Jaikrishnan R.

2000-01-01

Measurement of stress and strain in rotating turbomachinery is critical to many industries. The search for a non-contacting, non-interfering, non-degrading measurement system is on going and extensive. While several methods seem promising in theory, implementation has proven troublesome. This work uncovers and quantifies these implementation issues in the context of a laser measurement system. Both a Laser Doppler Velocimeter system and a displacement laser system are utilized. It is found that the key issues are signal to noise ratio, rigid body compensation, measurement location, and conversion of intermittent measurements to a continuous signal. Accounting for these factors leads to successful measurements. These results should lead to better ideas and more practical solutions to the non-contacting, non-degrading, non-interfering strain measurement system problem.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Eric C. D.; Talmadge, Michael; Dutta, Abhijit

This report was developed as part of the U.S. Department of Energy’s Bioenergy Technologies Office’s (BETO’s) efforts to enable the development of technologies for the production of infrastructure-compatible, cost-competitive liquid hydrocarbon fuels from lignocellulosic biomass feedstocks. The research funded by BETO is designed to advance the state of technology of biomass feedstock supply and logistics, conversion, and overall system sustainability. It is expected that these research improvements will be made within the 2022 timeframe. As part of their involvement in this research and development effort, the National Renewable Energy Laboratory and the Pacific Northwest National Laboratory investigate the economics ofmore » conversion pathways through the development of conceptual biorefinery process models and techno-economic analysis models. This report describes in detail one potential conversion process for the production of high-octane gasoline blendstock via indirect liquefaction of biomass. The processing steps of this pathway include the conversion of biomass to synthesis gas or syngas via indirect gasification, gas cleanup, catalytic conversion of syngas to methanol intermediate, methanol dehydration to dimethyl ether (DME), and catalytic conversion of DME to high-octane, gasoline-range hydrocarbon blendstock product. The conversion process configuration leverages technologies previously advanced by research funded by BETO and demonstrated in 2012 with the production of mixed alcohols from biomass. Biomass-derived syngas cleanup via reforming of tars and other hydrocarbons is one of the key technology advancements realized as part of this prior research and 2012 demonstrations. The process described in this report evaluates a new technology area for the downstream utilization of clean biomass-derived syngas for the production of high-octane hydrocarbon products through methanol and DME intermediates. In this process, methanol undergoes dehydration to DME, which is subsequently converted via homologation reactions to high-octane, gasoline-range hydrocarbon products.« less

A microcomputer-based position updating system for general aviation utilizing Loran-C

NASA Technical Reports Server (NTRS)

Fischer, J. P.

1982-01-01

Modern digital electronic technology is used to produce a device to convert LORAN C to useful pilot information using a simple software algebra and low cost microprocessor devices. Results indicate that the processor based LORAN C navigator has an accuracy of 1.0 nm or less over an area typically covered by a triad of Loran C stations and can execute a position update in less than 0.2 seconds. The system was tested in 30 hours of flight and proved that it can give reliable and accurate navigation information. Methods of converting time differences to position, design considerations for the microcomputer system, and the system for coordinate conversion are discussed. Testing with predetermined points and possible fixes for errors are also considered.

Performance analysis of 60-min to 1-min integration time rain rate conversion models in Malaysia

NASA Astrophysics Data System (ADS)

Ng, Yun-Yann; Singh, Mandeep Singh Jit; Thiruchelvam, Vinesh

2018-01-01

Utilizing the frequency band above 10 GHz is in focus nowadays as a result of the fast expansion of radio communication systems in Malaysia. However, rain fade is the critical factor in attenuation of signal propagation for frequencies above 10 GHz. Malaysia is located in a tropical and equatorial region with high rain intensity throughout the year, and this study will review rain distribution and evaluate the performance of 60-min to 1-min integration time rain rate conversion methods for Malaysia. Several conversion methods such as Segal, Chebil & Rahman, Burgeono, Emiliani, Lavergnat and Gole (LG), Simplified Moupfouma, Joo et al., fourth order polynomial fit and logarithmic model have been chosen to evaluate the performance to predict 1-min rain rate for 10 sites in Malaysia. After the completion of this research, the results show that Chebil & Rahman model, Lavergnat & Gole model, Fourth order polynomial fit and Logarithmic model have shown the best performances in 60-min to 1-min rain rate conversion over 10 sites. In conclusion, it is proven that there is no single model which can claim to perform the best across 10 sites. By averaging RMSE and SC-RMSE over 10 sites, Chebil and Rahman model is the best method.

The effects of aquaculture production noise on the growth, condition factor, feed conversion, and survival of rainbow trout, Oncorhynchus mykiss

USGS Publications Warehouse

Davidson, J.; Bebak, J.; Mazik, P.

2009-01-01

Intensive aquaculture systems, particularly recirculating systems, utilize equipment such as aerators, air and water pumps, blowers, and filtration systems that inadvertently increase noise levels in fish culture tanks. Sound levels and frequencies measured within intensive aquaculture systems are within the range of fish hearing, but species-specific effects of aquaculture production noise are not well defined. Field and laboratory studies have shown that fish behavior and physiology can be negatively impacted by intense sound. Therefore, chronic exposure to aquaculture production noise could cause increased stress, reduced growth rates and feed conversion efficiency, and decreased survival. The objective of this study was to provide an in-depth evaluation of the long term effects of aquaculture production noise on the growth, condition factor, feed conversion efficiency, and survival of cultured rainbow trout, Oncorhynchus mykiss. Rainbow trout were cultured in replicated tanks using two sound treatments: 117??dB re 1????Pa RMS which represented sound levels lower than those recorded in an intensive recycle system and 149??dB re 1????Pa RMS, representing sound levels near the upper limits known to occur in recycle systems. To begin the study mean fish weights in the 117 and 149??dB tanks were 40 and 39??g, respectively. After five months of exposure no significant differences were identified between treatments for mean weight, length, specific growth rates, condition factor, feed conversion, or survival (n = 4). Mean final weights for the 117 and 149??dB treatments were 641 ?? 3 and 631 ?? 10??g, respectively. Overall specific growth rates were equal, i.e. 1.84 ?? 0.00 and 1.84 ?? 0.01%/day. Analysis of growth rates of individually tagged rainbow trout indicated that fish from the 149??dB tanks grew slower during the first month of noise exposure (p < 0.05); however, fish acclimated to the noise thereafter. This study further suggests that rainbow trout growth and survival are unlikely to be affected over the long term by noise levels common to intensive aquaculture systems. ?? 2008 Elsevier B.V.

Is control through utilization a cost effective Prosopis juliflora management strategy?

PubMed

Wakie, Tewodros T; Hoag, Dana; Evangelista, Paul H; Luizza, Matthew; Laituri, Melinda

2016-03-01

The invasive tree Prosopis juliflora is known to cause negative impacts on invaded ranges. High P. juliflora eradication costs have swayed developing countries to follow a new and less expensive approach known as control through utilization. However, the net benefits of this new approach have not been thoroughly evaluated. Our objective was to assess the economic feasibility of selected P. juliflora eradication and utilization approaches that are currently practiced in one of the severely affected developing countries, Ethiopia. The selected approaches include converting P. juliflora infested lands into irrigated farms (conversion), charcoal production, and seed flour production. We estimate the costs and revenues of the selected P. juliflora eradication and utilization approaches by interviewing 19 enterprise owners. We assess the economic feasibility of the enterprises by performing enterprise, break-even, investment, sensitivity, and risk analyses. Our results show that conversion to irrigated cotton is economically profitable, with Net Present Value (NPV) of 5234 US$/ha over 10 years and an interest rate of 10% per year. Conversion greatly reduces the spread of P. juliflora on farmlands. Managing P. juliflora infested lands for charcoal production with a four-year harvest cycle is profitable, with NPV of 805 US$/ha. However, the production process needs vigilant regulation to protect native plants from exploitation and caution should be taken to prevent charcoal production sites from becoming potential seed sources. Though flour from P. juliflora pods can reduce invasions by destroying viable seeds, flour enterprises in Ethiopia are unprofitable. Conversion and charcoal production can be undertaken with small investment costs, while flour production requires high investment costs. Introducing new changes in the production and management steps of P. juliflora flour might be considered to make the enterprise profitable. Our study shows that control through utilization may be a viable P. juliflora management strategy under the right environmental setting. Published by Elsevier Ltd.

Using Telephone Conversations to Develop Awareness of Pragmatic Skills: An Activity-Theory-Driven Approach

ERIC Educational Resources Information Center

Xia, Saihua

2009-01-01

This paper investigates ESL learners' awareness of pragmatic skills utilizing an activity-theory driven approach to perform an inquiry task into problem-solving service call conversations (PSSCs) between native speakers (NS) and non-native speakers of English (NNSs). Eight high-intermediate ESL learners, from five different language backgrounds,…

Skills Conversion Project: Chapter 7, Power Resources. Final Report.

ERIC Educational Resources Information Center

National Society of Professional Engineers, Washington, DC.

The opportunity for employment of displaced aerospace and defense professionals within the electric power utility industry was investigated by the Seattle Skills Conversion Project Team of the National Society of Professional Engineers, as part of a study conducted for the U.S. Department of Labor. The study concluded that a possibility for…

Using Articulate Virtual Laboratories in Teaching Energy Conversion at the U.S. Naval Academy.

ERIC Educational Resources Information Center

Wu, C.

1998-01-01

The Mechanical Engineering Department at the U.S. Naval Academy is currently evaluating a new teaching method which uses computer software. Utilizing the thermodynamic-based software CyclePad, Intelligent Computer Aided Instruction is incorporated in an advanced energy conversion course for Mechanical Engineering students. The CyclePad software…

Utilizing the trophic interactions of nematodes as indicators of change in soil biota associated with the loss of bouteloua eriopda grasslands

USDA-ARS?s Scientific Manuscript database

Conversion of perennial grasslands to shrublands is a desertification process that is important globally. Changes in aboveground ecosystem properties with this conversion have been well-documented, but little is known about how belowground communities are affected, yet these belowground communities ...

Portfolio Based Faculty Development Conversations: A Model for Increasing Teaching Efficacy

ERIC Educational Resources Information Center

Crawford, Sabrina

2017-01-01

A shift in higher education towards increasing accountability for teaching effectiveness has institutions reevaluating how they utilize faculty evaluation tools. The purpose of this case study was to probe perceptions on the value of using teaching portfolios, supported by PLC conversations between faculty and deans, as an evaluation strategy that…

Solar thermal program summary. Volume 1: Overview, fiscal year 1988

NASA Astrophysics Data System (ADS)

1989-02-01

The goal of the solar thermal program is to improve overall solar thermal systems performance and provide cost-effective energy options that are strategically secure and environmentally benign. Major research activities include energy collection technology, energy conversion technology, and systems and applications technology for both CR and DR systems. This research is being conducted through research laboratories in close coordination with the solar thermal industry, utilities companies, and universities. The Solar Thermal Technology Program is pursuing the development of critical components and subsystems for improved energy collection and conversion devices. This development follows two basic paths: for CR systems, critical components include stretched membrane heliostats, direct absorption receivers (DARs), and transport subsystems for molten salt heat transfer fluids. These components offer the potential for a significant reduction in system costs; and for DR systems, critical components include stretched membrane dishes, reflux receivers, and Stirling engines. These components will significantly increase system reliability and efficiency, which will reduce costs. The major thrust of the program is to provide electric power. However, there is an increasing interest in the use of concentrated solar energy for applications such as detoxifying hazardous wastes and developing high-value transportable fuels. These potential uses of highly concentrated solar energy still require additional experiments to prove concept feasibility. The program goal of economically competitive energy reduction from solar thermal systems is being cooperatively addressed by industry and government.

Comparison of complication and conversion rates between robotic-assisted and laparoscopic rectal resection for rectal cancer: which patients and providers could benefit most from robotic-assisted surgery?

PubMed

Ackerman, Stacey J; Daniel, Shoshana; Baik, Rebecca; Liu, Emelline; Mehendale, Shilpa; Tackett, Scott; Hellan, Minia

2018-03-01

To compare (1) complication and (2) conversion rates to open surgery (OS) from laparoscopic surgery (LS) and robotic-assisted surgery (RA) for rectal cancer patients who underwent rectal resection. (3) To identify patient, physician, and hospital predictors of conversion. A US-based database study was conducted utilizing the 2012-2014 Premier Healthcare Data, including rectal cancer patients ≥18 with rectal resection. ICD-9-CM diagnosis and procedural codes were utilized to identify surgical approaches, conversions to OS, and surgical complications. Propensity score matching on patient, surgeon, and hospital level characteristics was used to create comparable groups of RA\\LS patients (n = 533 per group). Predictors of conversion from LS and RA to OS were identified with stepwise logistic regression in the unmatched sample. Post-match results suggested comparable perioperative complication rates (RA 29% vs LS 29%; p = .7784); whereas conversion rates to OS were 12% for RA vs 29% for LS (p < .0001). Colorectal surgeons (RA 9% vs LS 23%), general surgeons (RA 13% vs LS 35%), and smaller bed-size hospitals (RA 14% vs LS 33%) have reduced conversion rates for RA vs LS (p < .0001). Statistically significant predictors of conversion included LS, non-colorectal surgeon, and smaller bed-size hospitals. Retrospective observational study limitations apply. Analysis of the hospital administrative database was subject to the data captured in the database and the accuracy of coding. Propensity score matching limitations apply. RA and LS groups were balanced with respect to measured patient, surgeon, and hospital characteristics. Compared to LS, RA offers a higher probability of completing a successful minimally invasive surgery for rectal cancer patients undergoing rectal resection without exacerbating complications. Male, obese, or moderately-to-severely ill patients had higher conversion rates. While colorectal surgeons had lower conversion rates from RA than LS, the reduction was magnified for general surgeons and smaller bed-size hospitals.

Lignocellulose-Degrading Microbial Communities in Landfill Sites Represent a Repository of Unexplored Biomass-Degrading Diversity.

PubMed

Ransom-Jones, Emma; McCarthy, Alan J; Haldenby, Sam; Doonan, James; McDonald, James E

2017-01-01

The microbial conversion of lignocellulosic biomass for biofuel production represents a renewable alternative to fossil fuels. However, the discovery of new microbial enzymes with high activity is critical for improving biomass conversion processes. While attempts to identify superior lignocellulose-degrading enzymes have focused predominantly on the animal gut, biomass-degrading communities in landfill sites represent an unexplored resource of hydrolytic enzymes for biomass conversion. Here, to address the paucity of information on biomass-degrading microbial diversity beyond the gastrointestinal tract, cellulose (cotton) "baits" were incubated in landfill leachate microcosms to enrich the landfill cellulolytic microbial community for taxonomic and functional characterization. Metagenome and 16S rRNA gene amplicon sequencing demonstrated the dominance of Firmicutes , Bacteroidetes , Spirochaetes , and Fibrobacteres in the landfill cellulolytic community. Functional metagenome analysis revealed 8,371 carbohydrate active enzymes (CAZymes) belonging to 244 CAZyme families. In addition to observing biomass-degrading enzymes of anaerobic bacterial "cellulosome" systems of members of the Firmicutes , we report the first detection of the Fibrobacter cellulase system and the Bacteroidetes polysaccharide utilization locus (PUL) in landfill sites. These data provide evidence for the presence of multiple mechanisms of biomass degradation in the landfill microbiome and highlight the extraordinary functional diversity of landfill microorganisms as a rich source of biomass-degrading enzymes of potential biotechnological significance. IMPORTANCE The microbial conversion of lignocellulosic biomass for biofuel production represents a renewable alternative to fossil fuels. However, the discovery of new microbial enzymes with high activity is critical for improving biomass conversion processes. While attempts to identify superior lignocellulose-degrading enzymes have focused predominantly on the animal gut, biomass-degrading communities in landfill sites represent an unexplored resource of hydrolytic enzymes for biomass conversion. Here, we identified Firmicutes , Spirochaetes , and Fibrobacteres as key phyla in the landfill cellulolytic community, detecting 8,371 carbohydrate active enzymes (CAZymes) that represent at least three of the recognized strategies for cellulose decomposition. These data highlight substantial hydrolytic enzyme diversity in landfill sites as a source of new enzymes for biomass conversion.

Lignocellulose-Degrading Microbial Communities in Landfill Sites Represent a Repository of Unexplored Biomass-Degrading Diversity

PubMed Central

Ransom-Jones, Emma; McCarthy, Alan J.; Haldenby, Sam; Doonan, James

2017-01-01

ABSTRACT The microbial conversion of lignocellulosic biomass for biofuel production represents a renewable alternative to fossil fuels. However, the discovery of new microbial enzymes with high activity is critical for improving biomass conversion processes. While attempts to identify superior lignocellulose-degrading enzymes have focused predominantly on the animal gut, biomass-degrading communities in landfill sites represent an unexplored resource of hydrolytic enzymes for biomass conversion. Here, to address the paucity of information on biomass-degrading microbial diversity beyond the gastrointestinal tract, cellulose (cotton) “baits” were incubated in landfill leachate microcosms to enrich the landfill cellulolytic microbial community for taxonomic and functional characterization. Metagenome and 16S rRNA gene amplicon sequencing demonstrated the dominance of Firmicutes, Bacteroidetes, Spirochaetes, and Fibrobacteres in the landfill cellulolytic community. Functional metagenome analysis revealed 8,371 carbohydrate active enzymes (CAZymes) belonging to 244 CAZyme families. In addition to observing biomass-degrading enzymes of anaerobic bacterial “cellulosome” systems of members of the Firmicutes, we report the first detection of the Fibrobacter cellulase system and the Bacteroidetes polysaccharide utilization locus (PUL) in landfill sites. These data provide evidence for the presence of multiple mechanisms of biomass degradation in the landfill microbiome and highlight the extraordinary functional diversity of landfill microorganisms as a rich source of biomass-degrading enzymes of potential biotechnological significance. IMPORTANCE The microbial conversion of lignocellulosic biomass for biofuel production represents a renewable alternative to fossil fuels. However, the discovery of new microbial enzymes with high activity is critical for improving biomass conversion processes. While attempts to identify superior lignocellulose-degrading enzymes have focused predominantly on the animal gut, biomass-degrading communities in landfill sites represent an unexplored resource of hydrolytic enzymes for biomass conversion. Here, we identified Firmicutes, Spirochaetes, and Fibrobacteres as key phyla in the landfill cellulolytic community, detecting 8,371 carbohydrate active enzymes (CAZymes) that represent at least three of the recognized strategies for cellulose decomposition. These data highlight substantial hydrolytic enzyme diversity in landfill sites as a source of new enzymes for biomass conversion. PMID:28776044

Assessment of the technology required to develop photovoltaic power system for large scale national energy applications

NASA Technical Reports Server (NTRS)

Lutwack, R.

1974-01-01

A technical assessment of a program to develop photovoltaic power system technology for large-scale national energy applications was made by analyzing and judging the alternative candidate photovoltaic systems and development tasks. A program plan was constructed based on achieving the 10 year objective of a program to establish the practicability of large-scale terrestrial power installations using photovoltaic conversion arrays costing less than $0.50/peak W. Guidelines for the tasks of a 5 year program were derived from a set of 5 year objectives deduced from the 10 year objective. This report indicates the need for an early emphasis on the development of the single-crystal Si photovoltaic system for commercial utilization; a production goal of 5 x 10 to the 8th power peak W/year of $0.50 cells was projected for the year 1985. The developments of other photovoltaic conversion systems were assigned to longer range development roles. The status of the technology developments and the applicability of solar arrays in particular power installations, ranging from houses to central power plants, was scheduled to be verified in a series of demonstration projects. The budget recommended for the first 5 year phase of the program is $268.5M.

Satellite power system concept development and evaluation program system definition technical assessment report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1980-12-01

The results of the system definition studies conducted by NASA as a part of the Department of Energy/National Aeronautics and Space Administration SPS Concept Development and Evaluation Program are summarized. The purpose of the system definition efforts was to identify and define candidate SPS concepts and to evaluate the concepts in terms of technical and cost factors. Although the system definition efforts consisted primarily of evaluation and assessment of alternative technical approaches, a reference system was also defined to facilitate economic, environmental, and societal assessments by the Department of Energy. This reference system was designed to deliver 5 GW ofmore » electrical power to the utility grid. Topics covered include system definition; energy conversion and power management; power transmission and reception; structures, controls, and materials; construction and operations; and space transportation.« less

Methane utilization in Methylomicrobium alcaliphilum 20Z R: a systems approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akberdin, Ilya R.; Thompson, Merlin; Hamilton, Richard

Biological methane utilization, one of the main sinks of the greenhouse gas in nature, represents an attractive platform for production of fuels and value-added chemicals. Despite the progress made in our understanding of the individual parts of methane utilization, our knowledge of how the whole-cell metabolic network is organized and coordinated is limited. Attractive growth and methane-conversion rates, a complete and expert-annotated genome sequence, as well as large enzymatic, 13C-labeling, and transcriptomic datasets make Methylomicrobium alcaliphilum 20Z R an exceptional model system for investigating methane utilization networks. Here we present a comprehensive metabolic framework of methane and methanol utilization inmore » M. alcaliphilum 20Z R. A set of novel metabolic reactions governing carbon distribution across central pathways in methanotrophic bacteria was predicted by in-silico simulations and confirmed by global non-targeted metabolomics and enzymatic evidences. Our data highlight the importance of substitution of ATP-linked steps with PPi-dependent reactions and support the presence of a carbon shunt from acetyl-CoA to the pentose-phosphate pathway and highly branched TCA cycle. The diverged TCA reactions promote balance between anabolic reactions and redox demands. As a result, the computational framework of C 1-metabolism in methanotrophic bacteria can represent an efficient tool for metabolic engineering or ecosystem modeling.« less

Methane utilization in Methylomicrobium alcaliphilum 20Z R: a systems approach

DOE PAGES

Akberdin, Ilya R.; Thompson, Merlin; Hamilton, Richard; ...

2018-02-06

Biological methane utilization, one of the main sinks of the greenhouse gas in nature, represents an attractive platform for production of fuels and value-added chemicals. Despite the progress made in our understanding of the individual parts of methane utilization, our knowledge of how the whole-cell metabolic network is organized and coordinated is limited. Attractive growth and methane-conversion rates, a complete and expert-annotated genome sequence, as well as large enzymatic, 13C-labeling, and transcriptomic datasets make Methylomicrobium alcaliphilum 20Z R an exceptional model system for investigating methane utilization networks. Here we present a comprehensive metabolic framework of methane and methanol utilization inmore » M. alcaliphilum 20Z R. A set of novel metabolic reactions governing carbon distribution across central pathways in methanotrophic bacteria was predicted by in-silico simulations and confirmed by global non-targeted metabolomics and enzymatic evidences. Our data highlight the importance of substitution of ATP-linked steps with PPi-dependent reactions and support the presence of a carbon shunt from acetyl-CoA to the pentose-phosphate pathway and highly branched TCA cycle. The diverged TCA reactions promote balance between anabolic reactions and redox demands. As a result, the computational framework of C 1-metabolism in methanotrophic bacteria can represent an efficient tool for metabolic engineering or ecosystem modeling.« less

Methods for locating ground faults and insulation degradation condition in energy conversion systems

DOEpatents

Agamy, Mohamed; Elasser, Ahmed; Galbraith, Anthony William; Harfman Todorovic, Maja

2015-08-11

Methods for determining a ground fault or insulation degradation condition within energy conversion systems are described. A method for determining a ground fault within an energy conversion system may include, in part, a comparison of baseline waveform of differential current to a waveform of differential current during operation for a plurality of DC current carrying conductors in an energy conversion system. A method for determining insulation degradation within an energy conversion system may include, in part, a comparison of baseline frequency spectra of differential current to a frequency spectra of differential current transient at start-up for a plurality of DC current carrying conductors in an energy conversion system. In one embodiment, the energy conversion system may be a photovoltaic system.

Method of achieving ultra-wideband true-time-delay beam steering for active electronically scanned arrays

DOEpatents

Loui, Hung; Brock, Billy C.

2016-10-25

The various embodiments presented herein relate to beam steering an array antenna by modifying intermediate frequency (IF) waveforms prior to conversion to RF signals. For each channel, a direct digital synthesis (DDS) component can be utilized to generate a waveform or modify amplitude, timing and phase of a waveform relative to another waveform, whereby the generation/modification can be performed prior to the IF input port of a mixer on each channel. A local oscillator (LO) signal can be utilized to commonly drive each of the mixers. After conversion at the RF output port of each of the mixers, each RF signal can be transmitted by a respective antenna element in the antenna array. Initiation of transmission of each RF signal can be performed simultaneously at each antenna. The process can be reversed during receive whereby timing, amplitude, and phase of the received can be modified digitally post ADC conversion.

Investigation of current university research concerning energy conversion and conservation in small single-family dwellings

NASA Technical Reports Server (NTRS)

Grossman, G. R.; Roberts, A. S., Jr.

1975-01-01

An investigation was made of university research concerning energy conversion and conservation techniques which may be applied in small single-family residences. Information was accumulated through published papers, progress reports, telephone conversations, and personal interviews. A synopsis of each pertinent investigation is given. Finally, a discussion of the synopses is presented and recommendations are made concerning the applicability of concepts for the design and construction of NASA-Langley Research Center's proposed Technology Utilization House in Hampton, Virginia.

Methods and systems for producing syngas

DOEpatents

Hawkes, Grant L; O& #x27; Brien, James E; Stoots, Carl M; Herring, J. Stephen; McKellar, Michael G; Wood, Richard A; Carrington, Robert A; Boardman, Richard D

2013-02-05

Methods and systems are provided for producing syngas utilizing heat from thermochemical conversion of a carbonaceous fuel to support decomposition of at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells. Simultaneous decomposition of carbon dioxide and water or steam by one or more solid-oxide electrolysis cells may be employed to produce hydrogen and carbon monoxide. A portion of oxygen produced from at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells is fed at a controlled flow rate in a gasifier or combustor to oxidize the carbonaceous fuel to control the carbon dioxide to carbon monoxide ratio produced.

Iron-sulfide redox flow batteries

DOEpatents

Xia, Guanguang; Yang, Zhenguo; Li, Liyu; Kim, Soowhan; Liu, Jun; Graff, Gordon L

2016-06-14

Iron-sulfide redox flow battery (RFB) systems can be advantageous for energy storage, particularly when the electrolytes have pH values greater than 6. Such systems can exhibit excellent energy conversion efficiency and stability and can utilize low-cost materials that are relatively safer and more environmentally friendly. One example of an iron-sulfide RFB is characterized by a positive electrolyte that comprises Fe(III) and/or Fe(II) in a positive electrolyte supporting solution, a negative electrolyte that comprises S.sup.2- and/or S in a negative electrolyte supporting solution, and a membrane, or a separator, that separates the positive electrolyte and electrode from the negative electrolyte and electrode.

Iron-sulfide redox flow batteries

DOEpatents

Xia, Guan-Guang; Yang, Zhenguo; Li, Liyu; Kim, Soowhan; Liu, Jun; Graff, Gordon L

2013-12-17

Iron-sulfide redox flow battery (RFB) systems can be advantageous for energy storage, particularly when the electrolytes have pH values greater than 6. Such systems can exhibit excellent energy conversion efficiency and stability and can utilize low-cost materials that are relatively safer and more environmentally friendly. One example of an iron-sulfide RFB is characterized by a positive electrolyte that comprises Fe(III) and/or Fe(II) in a positive electrolyte supporting solution, a negative electrolyte that comprises S.sup.2- and/or S in a negative electrolyte supporting solution, and a membrane, or a separator, that separates the positive electrolyte and electrode from the negative electrolyte and electrode.

Synergistic enzymatic and microbial lignin conversion

DOE PAGES

Zhao, Cheng; Xie, Shangxian; Pu, Yunqiao; ...

2015-10-02

We represent the utilization of lignin for fungible fuels and chemicals and it's one of the most imminent challenges in modern biorefineries. However, bioconversion of lignin is highly challenging due to its recalcitrant nature as a phenolic heteropolymer. This study addressed the challenges by revealing the chemical and biological mechanisms for synergistic lignin degradation by a bacterial and enzymatic system, which significantly improved lignin consumption, cell growth and lipid yield. The Rhodococcus opacus cell growth increased exponentially in response to the level of laccase treatment, indicating the synergy between laccase and bacterial cells in lignin degradation. Other treatments like ironmore » and hydrogen peroxide showed limited impact on cell growth. Chemical analysis of lignin under various treatments further confirmed the synergy between laccase and cells at the chemical level. 31P nuclear magnetic resonance (NMR) suggested that laccase, R. opacus cell and Fenton reaction reagents promoted the degradation of different types of lignin functional groups, elucidating the chemical basis for the synergistic effects. 31P NMR further revealed that laccase treatment had the most significant impact for degrading the abundant chemical groups. The results were further confirmed by the molecular weight analysis and lignin quantification by the Prussian blue assay. The cell–laccase fermentation led to a 17-fold increase of lipid production. Overall, the study indicated that laccase and R. opacus can synergize to degrade lignin efficiently, likely through rapid utilization of monomers generated by laccase to promote the reaction toward depolymerization. The study provided a potential path for more efficient lignin conversion and development of consolidated lignin conversion.« less

Synergistic enzymatic and microbial lignin conversion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Cheng; Xie, Shangxian; Pu, Yunqiao

We represent the utilization of lignin for fungible fuels and chemicals and it's one of the most imminent challenges in modern biorefineries. However, bioconversion of lignin is highly challenging due to its recalcitrant nature as a phenolic heteropolymer. This study addressed the challenges by revealing the chemical and biological mechanisms for synergistic lignin degradation by a bacterial and enzymatic system, which significantly improved lignin consumption, cell growth and lipid yield. The Rhodococcus opacus cell growth increased exponentially in response to the level of laccase treatment, indicating the synergy between laccase and bacterial cells in lignin degradation. Other treatments like ironmore » and hydrogen peroxide showed limited impact on cell growth. Chemical analysis of lignin under various treatments further confirmed the synergy between laccase and cells at the chemical level. 31P nuclear magnetic resonance (NMR) suggested that laccase, R. opacus cell and Fenton reaction reagents promoted the degradation of different types of lignin functional groups, elucidating the chemical basis for the synergistic effects. 31P NMR further revealed that laccase treatment had the most significant impact for degrading the abundant chemical groups. The results were further confirmed by the molecular weight analysis and lignin quantification by the Prussian blue assay. The cell–laccase fermentation led to a 17-fold increase of lipid production. Overall, the study indicated that laccase and R. opacus can synergize to degrade lignin efficiently, likely through rapid utilization of monomers generated by laccase to promote the reaction toward depolymerization. The study provided a potential path for more efficient lignin conversion and development of consolidated lignin conversion.« less

Conversion-Integration of MSFC Nonlinear Signal Diagnostic Analysis Algorithms for Realtime Execution of MSFC's MPP Prototype System

NASA Technical Reports Server (NTRS)

Jong, Jen-Yi

1996-01-01

NASA's advanced propulsion system Small Scale Magnetic Disturbances/Advanced Technology Development (SSME/ATD) has been undergoing extensive flight certification and developmental testing, which involves large numbers of health monitoring measurements. To enhance engine safety and reliability, detailed analysis and evaluation of the measurement signals are mandatory to assess its dynamic characteristics and operational condition. Efficient and reliable signal detection techniques will reduce the risk of catastrophic system failures and expedite the evaluation of both flight and ground test data, and thereby reduce launch turn-around time. During the development of SSME, ASRI participated in the research and development of several advanced non- linear signal diagnostic methods for health monitoring and failure prediction in turbomachinery components. However, due to the intensive computational requirement associated with such advanced analysis tasks, current SSME dynamic data analysis and diagnostic evaluation is performed off-line following flight or ground test with a typical diagnostic turnaround time of one to two days. The objective of MSFC's MPP Prototype System is to eliminate such 'diagnostic lag time' by achieving signal processing and analysis in real-time. Such an on-line diagnostic system can provide sufficient lead time to initiate corrective action and also to enable efficient scheduling of inspection, maintenance and repair activities. The major objective of this project was to convert and implement a number of advanced nonlinear diagnostic DSP algorithms in a format consistent with that required for integration into the Vanderbilt Multigraph Architecture (MGA) Model Based Programming environment. This effort will allow the real-time execution of these algorithms using the MSFC MPP Prototype System. ASRI has completed the software conversion and integration of a sequence of nonlinear signal analysis techniques specified in the SOW for real-time execution on MSFC's MPP Prototype. This report documents and summarizes the results of the contract tasks; provides the complete computer source code; including all FORTRAN/C Utilities; and all other utilities/supporting software libraries that are required for operation.

Using changes in agricultural utility to quantify future climate-induced risk to conservation.

PubMed

Estes, Lyndon D; Paroz, Lydie-Line; Bradley, Bethany A; Green, Jonathan M H; Hole, David G; Holness, Stephen; Ziv, Guy; Oppenheimer, Michael G; Wilcove, David S

2014-04-01

Much of the biodiversity-related climate change impacts research has focused on the direct effects to species and ecosystems. Far less attention has been paid to the potential ecological consequences of human efforts to address the effects of climate change, which may equal or exceed the direct effects of climate change on biodiversity. One of the most significant human responses is likely to be mediated through changes in the agricultural utility of land. As farmers adapt their practices to changing climates, they may increase pressure on some areas that are important to conserve (conservation lands) whereas lessening it on others. We quantified how the agricultural utility of South African conservation lands may be altered by climate change. We assumed that the probability of an area being farmed is linked to the economic benefits of doing so, using land productivity values to represent production benefit and topographic ruggedness as a proxy for costs associated with mechanical workability. We computed current and future values of maize and wheat production in key conservation lands using the DSSAT4.5 model and 36 crop-climate response scenarios. Most conservation lands had, and were predicted to continue to have, low agricultural utility because of their location in rugged terrain. However, several areas were predicted to maintain or gain high agricultural utility and may therefore be at risk of near-term or future conversion to cropland. Conversely, some areas were predicted to decrease in agricultural utility and may therefore prove easier to protect from conversion. Our study provides an approximate but readily transferable method for incorporating potential human responses to climate change into conservation planning. © 2013 Society for Conservation Biology.

Mathematical structure of unit systems

NASA Astrophysics Data System (ADS)

Kitano, Masao

2013-05-01

We investigate the mathematical structure of unit systems and the relations between them. Looking over the entire set of unit systems, we can find a mathematical structure that is called preorder (or quasi-order). For some pair of unit systems, there exists a relation of preorder such that one unit system is transferable to the other unit system. The transfer (or conversion) is possible only when all of the quantities distinguishable in the latter system are always distinguishable in the former system. By utilizing this structure, we can systematically compare the representations in different unit systems. Especially, the equivalence class of unit systems (EUS) plays an important role because the representations of physical quantities and equations are of the same form in unit systems belonging to an EUS. The dimension of quantities is uniquely defined in each EUS. The EUS's form a partially ordered set. Using these mathematical structures, unit systems and EUS's are systematically classified and organized as a hierarchical tree.

Lifecycle assessment of microalgae to biofuel: Comparison of thermochemical processing pathways

DOE PAGES

Bennion, Edward P.; Ginosar, Daniel M.; Moses, John; ...

2015-01-16

Microalgae are currently being investigated as a renewable transportation fuel feedstock based on various advantages that include high annual yields, utilization of poor quality land, does not compete with food, and can be integrated with various waste streams. This study focuses on directly assessing the impact of two different thermochemical conversion technologies on the microalgae to biofuel process through life cycle assessment. A system boundary of a “well to pump” (WTP) is defined and includes sub-process models of the growth, dewatering, thermochemical bio-oil recovery, bio-oil stabilization, conversion to renewable diesel, and transport to the pump. Models were validated with experimentalmore » and literature data and are representative of an industrial-scale microalgae to biofuel process. Two different thermochemical bio-oil conversion systems are modeled and compared on a systems level, hydrothermal liquefaction (HTL) and pyrolysis. The environmental impact of the two pathways were quantified on the metrics of net energy ratio (NER), defined here as energy consumed over energy produced, and greenhouse gas (GHG) emissions. Results for WTP biofuel production through the HTL pathway were determined to be 1.23 for the NER and GHG emissions of -11.4 g CO 2-eq (MJ renewable diesel) -1. WTP biofuel production through the pyrolysis pathway results in a NER of 2.27 and GHG emissions of 210 g CO2 eq (MJ renewable diesel)-1. The large environmental impact associated with the pyrolysis pathway is attributed to feedstock drying requirements and combustion of co-products to improve system energetics. Discussion focuses on a detailed breakdown of the overall process energetics and GHGs, impact of modeling at laboratory- scale compared to industrial-scale, environmental impact sensitivity to engineering systems input parameters for future focused research and development and a comparison of results to literature.« less

Life cycle assessment of microalgae to biofuel: Thermochemical processing through hydrothermal liquefaction or pyrolysis

NASA Astrophysics Data System (ADS)

Bennion, Edward P.

Microalgae are currently being investigated as a renewable transportation fuel feedstock based on various advantages that include high annual yields, utilization of poor quality land, does not compete with food, and can be integrated with various waste streams. This study focuses on directly assessing the impact of two different thermochemical conversion technologies on the microalgae-to-biofuel process through life cycle assessment. A system boundary of a "well to pump" (WTP) is defined and includes sub-process models of the growth, dewatering, thermochemical bio-oil recovery, bio-oil stabilization, conversion to renewable diesel, and transport to the pump. Models were validated with experimental and literature data and are representative of an industrial-scale microalgae-to-biofuel process. Two different thermochemical bio-oil conversion systems are modeled and compared on a systems level, hydrothermal liquefaction (HTL) and pyrolysis. The environmental impact of the two pathways were quantified on the metrics of net energy ratio (NER), defined here as energy consumed over energy produced, and greenhouse gas (GHG) emissions. Results for WTP biofuel production through the HTL pathway were determined to be 1.23 for the NER and GHG emissions of -11.4 g CO2 eq (MJ renewable diesel)-1. WTP biofuel production through the pyrolysis pathway results in a NER of 2.27 and GHG emissions of 210 g CO2 eq (MJ renewable diesel)-1. The large environmental impact associated with the pyrolysis pathway is attributed to feedstock drying requirements and combustion of co-products to improve system energetics. Discussion focuses on a detailed breakdown of the overall process energetics and GHGs, impact of modeling at laboratory-scale compared to industrial-scale, environmental impact sensitivity to engineering systems input parameters for future focused research and development, and a comparison of results to literature.

Design and fabrication of cascaded dichromate gelatin holographic filters for spectrum-splitting PV systems

NASA Astrophysics Data System (ADS)

Wu, Yuechen; Chrysler, Benjamin; Kostuk, Raymond K.

2018-01-01

The technique of designing, optimizing, and fabricating broadband volume transmission holograms using dichromate gelatin (DCG) is summarized for solar spectrum-splitting applications. The spectrum-splitting photovoltaic (PV) system uses a series of single-bandgap PV cells that have different spectral conversion efficiency properties to more fully utilize the solar spectrum. In such a system, one or more high-performance optical filters are usually required to split the solar spectrum and efficiently send them to the corresponding PV cells. An ideal spectral filter should have a rectangular shape with sharp transition wavelengths. A methodology of designing and modeling a transmission DCG hologram using coupled wave analysis for different PV bandgap combinations is described. To achieve a broad diffraction bandwidth and sharp cutoff wavelength, a cascaded structure of multiple thick holograms is described. A search algorithm is then developed to optimize both single- and two-layer cascaded holographic spectrum-splitting elements for the best bandgap combinations of two- and three-junction spectrum-splitting photovoltaic (SSPV) systems illuminated under the AM1.5 solar spectrum. The power conversion efficiencies of the optimized systems are found to be 42.56% and 48.41%, respectively, using the detailed balance method, and show an improvement compared with a tandem multijunction system. A fabrication method for cascaded DCG holographic filters is also described and used to prototype the optimized filter for the three-junction SSPV system.

Biomass in the manufacture of industrial products—the use of proteins and amino acids

PubMed Central

Peter, Francisc; Sanders, Johan

2007-01-01

The depletion in fossil feedstocks, increasing oil prices, and the ecological problems associated with CO2 emissions are forcing the development of alternative resources for energy, transport fuels, and chemicals: the replacement of fossil resources with CO2 neutral biomass. Allied with this, the conversion of crude oil products utilizes primary products (ethylene, etc.) and their conversion to either materials or (functional) chemicals with the aid of co-reagents such as ammonia and various process steps to introduce functionalities such as -NH2 into the simple structures of the primary products. Conversely, many products found in biomass often contain functionalities. Therefore, it is attractive to exploit this to bypass the use, and preparation of, co-reagents as well as eliminating various process steps by utilizing suitable biomass-based precursors for the production of chemicals. It is the aim of this mini-review to describe the scope of the possibilities to generate current functionalized chemical materials using amino acids from biomass instead of fossil resources, thereby taking advantage of the biomass structure in a more efficient way than solely utilizing biomass for the production of fuels or electricity. PMID:17387469

Sequestration and utilization of carbon dioxide by chemical and biological methods for biofuels and biomaterials by chemoautotrophs: Opportunities and challenges.

PubMed

Thakur, Indu Shekhar; Kumar, Manish; Varjani, Sunita J; Wu, Yonghong; Gnansounou, Edgard; Ravindran, Sindhu

2018-05-01

To meet the CO 2 emission reduction targets, carbon dioxide capture and utilization (CCU) comes as an evolve technology. CCU concept is turning into a feedstock and technologies have been developed for transformation of CO 2 into useful organic products. At industrial scale, utilization of CO 2 as raw material is not much significant as compare to its abundance. Mechanisms in nature have evolved for carbon concentration, fixation and utilization. Assimilation and subsequent conversion of CO 2 into complex molecules are performed by the photosynthetic and chemolithotrophic organisms. In the last three decades, substantial research is carry out to discover chemical and biological conversion of CO 2 in various synthetic and biological materials, such as carboxylic acids, esters, lactones, polymer biodiesel, bio-plastics, bio-alcohols, exopolysaccharides. This review presents an over view of catalytic transformation of CO 2 into biofuels and biomaterials by chemical and biological methods. Copyright © 2018 Elsevier Ltd. All rights reserved.

Technological advances in CO2 conversion electro-biorefinery: A step toward commercialization.

PubMed

ElMekawy, Ahmed; Hegab, Hanaa M; Mohanakrishna, Gunda; Elbaz, Ashraf F; Bulut, Metin; Pant, Deepak

2016-09-01

The global atmospheric warming due to increased emissions of carbon dioxide (CO2) has attracted great attention in the last two decades. Although different CO2 capture and storage platforms have been proposed, the utilization of captured CO2 from industrial plants is progressively prevalent strategy due to concerns about the safety of terrestrial and aquatic CO2 storage. Two utilization forms were proposed, direct utilization of CO2 and conversion of CO2 to chemicals and energy products. The latter strategy includes the bioelectrochemical techniques in which electricity can be used as an energy source for the microbial catalytic production of fuels and other organic products from CO2. This approach is a potential technique in which CO2 emissions are not only reduced, but it also produce more value-added products. This review article highlights the different methodologies for the bioelectrochemical utilization of CO2, with distinctive focus on the potential opportunities for the commercialization of these techniques. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of the presence of Zymomonas anaerobia on the conversion of cellobiose, glucose, and xylose to ethanol by Clostridium saccharolyticum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Asther, M.; Khan, A.W.

1984-01-01

To convert sugar mixtures containing cellobiose, glucose, and xylose to ethanol in a single step, the possibility of using a coculture consisting of Clostridium saccharolyticum and Zymomonas anaerobia was studied. In monoculture, C. saccharolyticum utilized all three sugars; however, it preferentially utilized glucose and produced acetic acid in addition to ethanol. The formation of acetic acid from the metabolism of glucose inhibited the growth of C. saccharolyticum and, consequently, the utilization of cellobiose and xylose. In monoculture, Z. anaerobia utilized glucose at a rate of 50 g/L day, but it did not ferment cellobiose or xylose. In coculture, Z. anaerobiamore » converted most of the glucose to ethanol during the lag phase of growth of C. saccharolyticum, which then converted cellobiose and xylose to ethanol. The use of this coculture increased both the rate and the efficiency of the conversion of these three sugars to ethanol, and produced relatively small amounts of acetic acid.« less

Towards understanding the kinetic behaviour and limitations in photo-induced copper(i) catalyzed azide-alkyne cycloaddition (CuAAC) reactions.

PubMed

El-Zaatari, Bassil M; Shete, Abhishek U; Adzima, Brian J; Kloxin, Christopher J

2016-09-14

The kinetic behaviour of the photo-induced copper(i) catalyzed azide-alkyne cycloaddition (CuAAC) reaction was studied in detail using real-time Fourier transform infrared (FTIR) spectroscopy on both a solvent-based monofunctional and a neat polymer network forming system. The results in the solvent-based system showed near first-order kinetics on copper and photoinitiator concentrations up to a threshold value in which the kinetics switch to zeroth-order. This kinetic shift shows that the photo-CuAAC reaction is not susceptible from side reactions such as copper disproportionation, copper(i) reduction, and radical termination at the early stages of the reaction. The overall reaction rate and conversion is highly dependent on the initial concentrations of photoinitiator and copper(ii) as well as their relative ratios. The conversion was decreased when an excess of photoinitiator was utilized compared to its threshold value. Interestingly, the reaction showed an induction period at relatively low intensities. The induction period is decreased by increasing light intensity and photoinitiator concentration. The reaction trends and limitations were further observed in a solventless polymer network forming system, exhibiting a similar copper and photoinitiator threshold behaviour.

Towards understanding the kinetic behaviour and limitations in photo-induced copper(I) catalyzed azide-alkyne cycloaddition (CuAAC) reactions

PubMed Central

El-Zaatari, Bassil M.; Shete, Abhishek U.; Adzima, Brian J.; Kloxin, Christopher J.

2016-01-01

The kinetic behaviour of the photo-induced copper(I) catalyzed azide—alkyne cycloaddition (CuAAC) reaction was studied in detail using real-time Fourier Transform Infrared Spectroscopy (FTIR) on both a solvent-based monofunctional and a neat polymer network forming system. The results in the solvent-based system showed near first-order kinetics on copper and photoinitiator concentrations up to a threshold value in which the kinetics switch to zeroth-order. This kinetic shift shows that the photo-CuAAC reaction is not suseptible from side reactions such as copper disproportionation, copper(I) reduction, and radical termination at the early stages of the reaction. The overall reaction rate and conversion is highly dependent on the initial concentrations of photoinitiator and copper(II), as well as their relative ratios. The conversion was decreased when an excess of photoinitiator was utilized compared to its threshold value. Interestingly, the reaction showed an induction period at relatively low intensities. The induction period is decreased by increasing light intensity, and photoinitiator concentration. The reaction trends and limitations were further observed in a solventless polymer network forming system, exhibiting a similar copper and photoinitiator threshold behaviour. PMID:27711587

Supporting Technology at GRC to Mitigate Risk as Stirling Power Conversion Transitions to Flight

NASA Technical Reports Server (NTRS)

Schreiber, Jeffrey G.; Thieme, Lanny G.; Wong, Wayne A.

2009-01-01

Stirling power conversion technology has been reaching more advanced levels of maturity during its development for space power applications. The current effort is in support of the Advanced Stirling Radioisotope Generator (ASRG), which is being developed by the U.S. Department of Energy (DOE), Lockheed Martin Space Systems Company (LMSSC), Sunpower Inc., and the NASA Glenn Research Center (GRC). This generator would use two high-efficiency Advanced Stirling Convertors (ASCs) to convert thermal energy from a radioisotope heat source into electricity. Of paramount importance is the reliability of the power system and as a part of this, the Stirling power convertors. GRC has established a supporting technology effort with tasks in the areas of reliability, convertor testing, high-temperature materials, structures, advanced analysis, organics, and permanent magnets. The project utilizes the matrix system at GRC to make use of resident experts in each of the aforementioned fields. Each task is intended to reduce risk and enhance reliability of the convertor as this technology transitions toward flight status. This paper will provide an overview of each task, outline the recent efforts and accomplishments, and show how they mitigate risk and impact the reliability of the ASC s and ultimately, the ASRG.

Isolated and soft-switched power converter

DOEpatents

Peng, Fang Zheng; Adams, Donald Joe

2002-01-01

An isolated and soft-switched power converter is used for DC/DC and DC/DC/AC power conversion. The power converter includes two resonant tank circuits coupled back-to-back through an isolation transformer. Each resonant tank circuit includes a pair of resonant capacitors connected in series as a resonant leg, a pair of tank capacitors connected in series as a tank leg, and a pair of switching devices with anti-parallel clamping diodes coupled in series as resonant switches and clamping devices for the resonant leg. The power converter is well suited for DC/DC and DC/DC/AC power conversion applications in which high-voltage isolation, DC to DC voltage boost, bidirectional power flow, and a minimal number of conventional switching components are important design objectives. For example, the power converter is especially well suited to electric vehicle applications and load-side electric generation and storage systems, and other applications in which these objectives are important. The power converter may be used for many different applications, including electric vehicles, hybrid combustion/electric vehicles, fuel-cell powered vehicles with low-voltage starting, remote power sources utilizing low-voltage DC power sources, such as photovoltaics and others, electric power backup systems, and load-side electric storage and generation systems.

Supporting Technology at GRC to Mitigate Risk as Stirling Power Conversion Transitions to Flight

NASA Technical Reports Server (NTRS)

Schreiber, Jeffrey G.; Thieme, Lanny G.; Wong, Wayne A.

2008-01-01

Stirling power conversion technology has been reaching more advanced levels of maturity during its development for space power applications. The current effort is in support of the Advanced Stirling Radioisotope Generator (ASRG), which is being developed by the U.S. Department of Energy (DOE), Lockheed Martin Space Systems Company (LMSSC), Sunpower Inc., and the NASA Glenn Research Center (GRC). This generator would use two high-efficiency Advanced Stirling Convertors (ASCs) to convert thermal energy from a radioisotope heat source into electricity. Of paramount importance is the reliability of the power system and as a part of this, the Stirling power convertors. GRC has established a supporting technology effort with tasks in the areas of reliability, convertor testing, high-temperature materials, structures, advanced analysis, organics, and permanent magnets. The project utilizes the matrix system at GRC to make use of resident experts in each of the aforementioned fields. Each task is intended to reduce risk and enhance reliability of the convertor as this technology transitions toward flight status. This paper will provide an overview of each task, outline the recent efforts and accomplishments, and show how they mitigate risk and impact the reliability of the ASC s and ultimately, the ASRG.

Research on application of photoelectric rotary encoder in space optical remote sensor

NASA Astrophysics Data System (ADS)

Zheng, Jun; Qi, Shao-fan; Wang, Yuan-yuan; Zhang, Zhan-dong

2016-11-01

For space optical remote sensor, especially wide swath detecting sensor, the focusing control system for the focal plane should be well designed to obtain the best image quality. The crucial part of this system is the measuring instrument. For previous implements, the potentiometer, which is essentially a voltage divider, is usually introduced to conduct the position in feedback closed-loop control process system. However, the performances of both electro-mechanical and digital potentiometers is limited in accuracy, temperature coefficients, and scale range. To have a better performance of focal plane moving detection, this article presents a new measuring implement with photoelectric rotary encoder, which consists of the photoelectric conversion system and the signal process system. In this novel focusing control system, the photoelectric conversion system is fixed on main axis, which can transform the angle information into a certain analog signal. Through the signal process system, after analog-to-digital converting and data format processing of the certain analog signal, the focusing control system can receive the digital precision angle position which can be used to deduct the current moving position of the focal plane. For utilization of space optical remote sensor in aerospace areas, the reliability design of photoelectric rotary encoder system should be considered with highest priority. As mentioned above, this photoelectric digital precision angle measurement device is well designed for this real-time control and dynamic measurement system, because its characters of high resolution, high accuracy, long endurance, and easy to maintain.

Raising the Question Number 1. Is the Rush to Provide On-Line Instruction Setting Our Students Up for Failure?

ERIC Educational Resources Information Center

Allen, Terre H.

2006-01-01

This essay is designed to engage academic discipline in a conversation about the utility and practices associated with providing communication coursework online, particularly general education, communication skills courses. The author has framed the conversation in terms of student success, retention, and degree completion. He outlines three…

High-flux solar-driven thermochemical dissociation of CO2 and H2O using nonstoichiometric ceria.

PubMed

Chueh, William C; Falter, Christoph; Abbott, Mandy; Scipio, Danien; Furler, Philipp; Haile, Sossina M; Steinfeld, Aldo

2010-12-24

Because solar energy is available in large excess relative to current rates of energy consumption, effective conversion of this renewable yet intermittent resource into a transportable and dispatchable chemical fuel may ensure the goal of a sustainable energy future. However, low conversion efficiencies, particularly with CO(2) reduction, as well as utilization of precious materials have limited the practical generation of solar fuels. By using a solar cavity-receiver reactor, we combined the oxygen uptake and release capacity of cerium oxide and facile catalysis at elevated temperatures to thermochemically dissociate CO(2) and H(2)O, yielding CO and H(2), respectively. Stable and rapid generation of fuel was demonstrated over 500 cycles. Solar-to-fuel efficiencies of 0.7 to 0.8% were achieved and shown to be largely limited by the system scale and design rather than by chemistry.

Current challenges in organic photovoltaic solar energy conversion.

PubMed

Schlenker, Cody W; Thompson, Mark E

2012-01-01

Over the last 10 years, significant interest in utilizing conjugated organic molecules for solid-state solar to electric conversion has produced rapid improvement in device efficiencies. Organic photovoltaic (OPV) devices are attractive for their compatibility with low-cost processing techniques and thin-film applicability to flexible and conformal applications. However, many of the processes that lead to power losses in these systems still remain poorly understood, posing a significant challenge for the future efficiency improvements required to make these devices an attractive solar technology. While semiconductor band models have been employed to describe OPV operation, a more appropriate molecular picture of the pertinent processes is beginning to emerge. This chapter presents mechanisms of OPV device operation, based on the bound molecular nature of the involved transient species. With the intention to underscore the importance of considering both thermodynamic and kinetic factors, recent progress in elucidating molecular characteristics that dictate photovoltage losses in heterojunction organic photovoltaics is also discussed.

In-Situ Resource Utilization Experiment for the Asteroid Redirect Crewed Mission

NASA Astrophysics Data System (ADS)

Elliott, J.; Fries, M.; Love, S.; Sellar, R. G.; Voecks, G.; Wilson, D.

2015-10-01

The Asteroid Redirect Crewed Mission (ARCM) represents a unique opportunity to perform in-situ testing of concepts that could lead to full-scale exploitation of asteroids for their valuable resources [1]. This paper describes a concept for an astronautoperated "suitcase" experiment to would demonstrate asteroid volatile extraction using a solar-heated oven and integral cold trap in a configuration scalable to full-size asteroids. Conversion of liberated water into H2 and O2 products would also be demonstrated through an integral processing and storage unit. The plan also includes development of a local prospecting system consisting of a suit-mounted multi-spectral imager to aid the crew in choosing optimal samples, both for In-Situ Resource Utilization (ISRU) and for potential return to Earth.

Solar power satellites - Heat engine or solar cells

NASA Technical Reports Server (NTRS)

Oman, H.; Gregory, D. L.

1978-01-01

A solar power satellite is the energy-converting element of a system that can deliver some 10 GW of power to utilities on the earth's surface. We evaluated heat engines and solar cells for converting sunshine to electric power at the satellite. A potassium Rankine cycle was the best of the heat engines, and 50 microns thick single-crystal silicon cells were the best of the photovoltaic converters. Neither solar cells nor heat engines had a clear advantage when all factors were considered. The potassium-turbine power plant, however, was more difficult to assemble and required a more expensive orbital assembly base. We therefore based our cost analyses on solar-cell energy conversion, concluding that satellite-generated power could be delivered to utilities for around 4 to 5 cents a kWh.

5 CFR 9901.371 - Conversion into NSPS pay system.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Conversion into NSPS pay system. 9901.371... SECURITY PERSONNEL SYSTEM (NSPS) Pay and Pay Administration Conversion Provisions § 9901.371 Conversion....231 for conversion rules related to determining an employee's career group, pay schedule, and band...

Optical Analysis of Transparent Polymeric Material Exposed to Simulated Space Environment

NASA Technical Reports Server (NTRS)

Edwards, David L.; Finckenor, Miria M.

1999-01-01

Transparent polymeric materials are being designed and utilized as solar concentrating lenses for spacecraft power and propulsion systems. These polymeric lenses concentrate solar energy onto energy conversion devices such as solar cells and thermal energy systems. The conversion efficiency is directly related to the transmissivity of the polymeric lens. The Environmental Effects Group of the Marshall Space Flight Center's Materials, Processes, and Manufacturing Department exposed a variety of materials to a simulated space environment and evaluated them for an, change in optical transmission. These materials include Lexan(TM), polyethylene terephthalate (PET). several formulations of Tefzel(TM). and Teflon(TM), and silicone DC 93-500. Samples were exposed to a minimum of 1000 Equivalent Sun Hours (ESH) of near-UV radiation (250 - 400 nm wavelength). Data will be presented on materials exposed to charged particle radiation equivalent to a five-year dose in geosynchronous orbit. These exposures were performed in MSFC's Combined Environmental Effects Test Chamber, a unique facility with the capability to expose materials simultaneously or sequentially to protons, low-energy electrons, high-energy electrons, near UV radiation and vacuum UV radiation.Prolonged exposure to the space environment will decrease the polymer film's transmission and thus reduce the conversion efficiency. A method was developed to normalize the transmission loss and thus rank the materials according to their tolerance to space environmental exposure. Spectral results and the material ranking according to transmission loss are presented.

Lunar power systems

NASA Technical Reports Server (NTRS)

1986-01-01

The findings of a study on the feasibility of several methods of providing electrical power for a permanently manned lunar base are provided. Two fundamentally different methods for lunar electrical power generation are considered. One is the use of a small nuclear reactor and the other is the conversion of solar energy to electricity. The baseline goal was to initially provide 300 kW of power with growth capability to one megawatt and eventually to 10 megawatts. A detailed, day by day scenario for the establishment, build-up, and operational activity of the lunar base is presented. Also presented is a conceptual approach to a supporting transportation system which identifies the number, type, and deployment of transportation vehicles required to support the base. An approach to the use of solar cells in the lunar environment was developed. There are a number of heat engines which are applicable to solar/electric conversions, and these are examined. Several approaches to energy storage which were used by the electric power utilities were examined and those which could be used at a lunar base were identified.

Space-based solar power conversion and delivery systems study. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Hazelrigg, G. A., Jr.

1976-01-01

The technical and economic aspects of satellite solar power systems are presented with a focus on the current configuration 5000 MW system. The technical studies include analyses of the orbital system structures, control and stationkeeping, and the formulation of program plans and costs for input to the economic analyses. The economic analyses centered about the development and use of a risk analysis model for a system cost assessment, identification of critical issues and technologies, and to provide information for programmatic decision making. A preliminary economic examination of some utility interface issues is included. Under the present state-of-knowledge, it is possible to formulate a program plan for the development of a satellite solar power system that can be economically justified. The key area of technological uncertainty is man's ability to fabricate and assemble large structures in space.

Improving healthcare value through clinical community and supply chain collaboration.

PubMed

Ishii, Lisa; Demski, Renee; Ken Lee, K H; Mustafa, Zishan; Frank, Steve; Wolisnky, Jean Paul; Cohen, David; Khanna, Jay; Ammerman, Joshua; Khanuja, Harpal S; Unger, Anthony S; Gould, Lois; Wachter, Patricia Ann; Stearns, Lauren; Werthman, Ronald; Pronovost, Peter

2017-03-01

We hypothesized that integrating supply chain with clinical communities would allow for clinician-led supply cost reduction and improved value in an academic health system. Three clinical communities (spine, joint, blood management) and one clinical community-like physician led team of surgeon stakeholders partnered with the supply chain team on specific supply cost initiatives. The teams reviewed their specific utilization and cost data, and the physicians led consensus-building conversations over a series of team meetings to agree to standard supply utilization. The spine and joint clinical communities each agreed upon a vendor capping model that led to cost savings of $3 million dollars and $1.5 million dollars respectively. The blood management decreased blood product utilization and achieved $1.2 million dollars savings. $5.6 million dollars in savings was achieved by a clinical community-like group of surgeon stakeholders through standardization of sutures and endomechanicals. Physician led clinical teams empowered to lead change achieved substantial supply chain cost savings in an academic health system. The model of combining clinical communities with supply chain offers hope for an effective, practical, and scalable approach to improving value and engaging physicians in other academic health systems. This clinician led model could benefit both private and academic health systems engaging in value optimization efforts. N/A. Copyright © 2016 Elsevier Inc. All rights reserved.

Biological Systems for Hydrogen Photoproduction (Presentation)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghirardi, M. L.

2012-05-01

This presentation summarizes NREL biological systems for hydrogen photoproduction work for the DOE Hydrogen and Fuel Cells Program Annual Merit Review and Peer Evaluation Meeting, May 14-18, 2012. General goal is develop photobiological systems for large-scale, low cost and efficient H{sub 2} production from water (barriers AH, AI and AJ). Specific tasks are: (1) Address the O{sub 2} sensitivity of hydrogenases that prevent continuity of H{sub 2} photoproduction under aerobic, high solar-to-hydrogen (STH) light conversion efficiency conditions; and (2) Utilize a limited STH H{sub 2}-producing method (sulfur deprivation) as a platform to address or test other factors limiting commercial algalmore » H{sub 2} photoproduction, including low rates due to biochemical and engineering mechanisms.« less

Solar energy conversion through the interaction of plasmons with tunnel junctions. Part A: Solar cell analysis. Part B: Photoconductor analysis

NASA Technical Reports Server (NTRS)

Welsh, P. E.; Schwartz, R. J.

1988-01-01

A solar cell utilizing guided optical waves and tunnel junctions was analyzed to determine its feasibility. From this analysis, it appears that the limits imposed upon conventional multiple cell systems also limit this solar cell. Due to this limitation, it appears that the relative simplicity of the conventional multiple cell systems over the solar cell make the conventional multiple cell systems the more promising candidate for improvement. It was discovered that some superlattice structures studied could be incorporated into an infrared photodetector. This photoconductor appears to be promising as a high speed, sensitive (high D sup star sub BLIP) detector in the wavelength range from 15 to over 100 micrometers.

Gas-turbine critical research and advanced technology support project

NASA Technical Reports Server (NTRS)

Clark, J. S.; Hodge, P. E.; Lowell, C. E.; Anderson, D. N.; Schultz, D. F.

1981-01-01

A technology data base for utility gas turbine systems capable of burning coal derived fuels was developed. The following areas are investigated: combustion; materials; and system studies. A two stage test rig is designed to study the conversion of fuel bound nitrogen to NOx. The feasibility of using heavy fuels in catalytic combustors is evaluated. A statistically designed series of hot corrosion burner rig tests was conducted to measure the corrosion rates of typical gas turbine alloys with several fuel contaminants. Fuel additives and several advanced thermal barrier coatings are tested. Thermal barrier coatings used in conjunction with low critical alloys and those used in a combined cycle system in which the stack temperature was maintained above the acid corrosion temperature are also studied.

Iron aluminide alloys with improved properties for high temperature applications

DOEpatents

McKamey, C.G.; Liu, C.T.

1990-10-09

An improved iron aluminide alloy of the DO[sub 3] type is described that has increased room temperature ductility and improved high elevated temperature strength. The alloy system further is resistant to corrosive attack in the environments of advanced energy conversion systems such as those using fossil fuels. The resultant alloy is relatively inexpensive as contrasted to nickel based and high nickel steels currently utilized for structural components. The alloy system consists essentially of 26--30 at. % aluminum, 0.5--10 at. % chromium, 0.02--0.3 at. % boron plus carbon, up to 2 at. % molybdenum, up to 1 at. % niobium, up to 0.5 at. % zirconium, up to 0.1 at. % yttrium, up to 0.5 at. % vanadium and the balance iron. 3 figs.

Preliminary designs for 25 kWe advanced Stirling conversion systems for dish electric applications

NASA Technical Reports Server (NTRS)

Shaltens, Richard K.; Schreiber, Jeffrey G.

1990-01-01

Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for terrestrial Solar Distributed Heat Receivers. The Stirling engine has been identified by Sandia as one of the most promising engines for terrestrial applications. The Stirling engine also has the potential to meet DOE's performance and cost goals. The NASA Lewis Research Center is conducting Stirling engine technology development activities directed toward a dynamic power source for space applications. Space power systems requirements include high reliability, very long life, low vibration and high efficiency. The free-piston Stirling engine has the potential for future high power space conversion systems, either nuclear or solar powered. Although both applications appear to be quite different, their requirements complement each other. Preliminary designs feature a free-piston Stirling engine, a liquid metal heat transport system, and a means to provide nominally 25 kW electric power to a utility grid while meeting DOE's performance and long term cost goals. The Cummins design incorporates a linear alternator to provide the electrical output, while the STC design generates electrical power indirectly through a hydraulic pump/motor coupled to an induction generator. Both designs for the ASCS's will use technology which can reasonably be expected to be available in the early 1990's.

Preliminary designs for 25 kWe advanced Stirling conversion systems for dish electric applications

NASA Astrophysics Data System (ADS)

Shaltens, Richard K.; Schreiber, Jeffrey G.

Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for terrestrial Solar Distributed Heat Receivers. The Stirling engine has been identified by Sandia as one of the most promising engines for terrestrial applications. The Stirling engine also has the potential to meet DOE's performance and cost goals. The NASA Lewis Research Center is conducting Stirling engine technology development activities directed toward a dynamic power source for space applications. Space power systems requirements include high reliability, very long life, low vibration and high efficiency. The free-piston Stirling engine has the potential for future high power space conversion systems, either nuclear or solar powered. Although both applications appear to be quite different, their requirements complement each other. Preliminary designs feature a free-piston Stirling engine, a liquid metal heat transport system, and a means to provide nominally 25 kW electric power to a utility grid while meeting DOE's performance and long term cost goals. The Cummins design incorporates a linear alternator to provide the electrical output, while the STC design generates electrical power indirectly through a hydraulic pump/motor coupled to an induction generator. Both designs for the ASCS's will use technology which can reasonably be expected to be available in the early 1990's.

Preliminary designs for 25 kWe advanced Stirling conversion systems for dish electric applications

NASA Technical Reports Server (NTRS)

Shaltens, Richard K.; Schreiber, Jeffrey G.

1990-01-01

Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for terrestrial Solar Distributed Heat Receivers. The Stirling engine has been identified by Sandia as one of the most promising engines for terrestrial applications. The Stirling engine also has the potential to meet DOE's performance and cost goals. The NASA Lewis Research Center is conducting Stirling engine technology development activities directed toward a dynamic power source for space applications. Space power systems requirements include high reliability, very long life, low vibration and high efficiency. The free-piston Stirling engine has the potential for future high power space conversion systems, either nuclear or solar powered. Although both applications appear to be quite different, their requirements complement each other. Preliminary designs feature a free-piston Stirling engine, a liquid metal heat transport system, and a means to provide nominally 25 kW electric power to a utility grid while meeting DOE's performance and long term cost goals. The Cummins design incorporates a linear alternator to provide the electrical output, while the STC design generates electrical power indirectly through a hydraulic pump/motor coupled to an induction generator. Both designs for the ASCS's will use technology which can reasonably be expected to be available in the early 1990's

Conceptual Core Analysis of Long Life PWR Utilizing Thorium-Uranium Fuel Cycle

NASA Astrophysics Data System (ADS)

Rouf; Su'ud, Zaki

2016-08-01

Conceptual core analysis of long life PWR utilizing thorium-uranium based fuel has conducted. The purpose of this study is to evaluate neutronic behavior of reactor core using combined thorium and enriched uranium fuel. Based on this fuel composition, reactor core have higher conversion ratio rather than conventional fuel which could give longer operation length. This simulation performed using SRAC Code System based on library SRACLIB-JDL32. The calculation carried out for (Th-U)O2 and (Th-U)C fuel with uranium composition 30 - 40% and gadolinium (Gd2O3) as burnable poison 0,0125%. The fuel composition adjusted to obtain burn up length 10 - 15 years under thermal power 600 - 1000 MWt. The key properties such as uranium enrichment, fuel volume fraction, percentage of uranium are evaluated. Core calculation on this study adopted R-Z geometry divided by 3 region, each region have different uranium enrichment. The result show multiplication factor every burn up step for 15 years operation length, power distribution behavior, power peaking factor, and conversion ratio. The optimum core design achieved when thermal power 600 MWt, percentage of uranium 35%, U-235 enrichment 11 - 13%, with 14 years operation length, axial and radial power peaking factor about 1.5 and 1.2 respectively.

Microreactor Development for Martian In-Situ Propellant Production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holladay, Jamie D.; Brooks, Kriston P.; Wegeng, Robert S.

2007-01-30

The second part of the Martian In-situ Propellant Production (MIPPS) system reviews the development of the Sabatier Reactor (SR). The microchannel SR had integrated cooling channels as well as reaction channels. It was <100cc in volume. The reactor utilized a proprietary catalyst. When operated at 400oC 70-80% CO2 conversion was achieved which enabled ~0.0125 kg CH4/hr production, or 1/8th the target mission. The modular design of the microchannel reactors would enable simple scale up to full scale production for the proposed mission.

Cartographic projection procedures for the UNIX environment; a user's manual

USGS Publications Warehouse

Evenden, Gerald I.

1990-01-01

A tutorial description of the general usage of the cartographic projection program proj (release 3) along with specic cartographic parameters and illustrations of the ap- proximately 70 cartographic projections supported by the program is presented. The program is designed as a standard Unix lter utility to be employed with other pro- grams in the generation of maps and charts and, in many cases, used in map digitizing applications. Tables and shell scripts are also provided for conversion of State Plane Coordinate Systems to and from geographic coordinates.

Satellite Power Systems (SPS) concept definition study. Volume 6: In-depth element investigation

NASA Technical Reports Server (NTRS)

Hanley, G. M.

1980-01-01

The fabrication parameters of GaAs MESFET solid-state amplifiers considering a power added conversion efficiency of at least 80% and power gains of at least 10dB were determined. Operating frequency was 2.45 GHz although 914 MHz was also considered. Basic circuit to be considered was either Class C or Class E amplification. Two modeling programs were utilized. The results of several computer calculations considering differing loads, temperatures, and efficiencies are presented. Parametric data in both tabular and plotted form are presented.

Growth of copper phthalocyanine rods on Au plasmon electrodes through micelle disruption methods.

PubMed

Chen, Wei-Hung; Ko, Wen-Yin; Chen, Ying-Shiou; Cheng, Ching-Yuan; Chan, Chi-Ming; Lin, Kuan-Jiuh

2010-02-16

To improve the efficiency of the photocurrent conversion process, we have utilized copper phthalocyanine (CuPc) rods, which are capable of enhancing the interfacial area of electron transport and plasmonic gold nanoparticles (Au NPs), which can increase the separation and photogeneration of excitons, to produce a more effective system. In-plane horizontal CuPc rods, with diameters ranging from 0.2 to 1.5 microm, were electrodeposited onto the surface of plasmonic (Au NP) monolayers predeposited onto ITO substrates through electrolytic micelle disruption (EMD) methods.

Hall Probe Calibration System Design for the Mu2e Solenoid Field Mapping System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Orozco, Charles; Elementi, Luciano; Feher, Sandor

The goal of the Mu2e experiment at Fermilab is to search for charged-lepton flavor violation by looking for neutrino-less muon to electron conversion in the field of the nucleus. The Mu2e experimental apparatus utilizes a complex magnetic field in the muon generation and momentum and charge selection process. Precise knowledge of the magnetic field is crucial. It is planned to map the solenoid field with calibrated 3D Hall probes up to 10 -5 accuracy. Here, this article describes a new design of a Hall probe calibration system that will be used to calibrate 3D Hall probes to better than 10more » -5 accuracy for the Mu2e Solenoid Field Mapping System.« less

Hall Probe Calibration System Design for the Mu2e Solenoid Field Mapping System

DOE PAGES

Orozco, Charles; Elementi, Luciano; Feher, Sandor; ...

2018-02-22

The goal of the Mu2e experiment at Fermilab is to search for charged-lepton flavor violation by looking for neutrino-less muon to electron conversion in the field of the nucleus. The Mu2e experimental apparatus utilizes a complex magnetic field in the muon generation and momentum and charge selection process. Precise knowledge of the magnetic field is crucial. It is planned to map the solenoid field with calibrated 3D Hall probes up to 10 -5 accuracy. Here, this article describes a new design of a Hall probe calibration system that will be used to calibrate 3D Hall probes to better than 10more » -5 accuracy for the Mu2e Solenoid Field Mapping System.« less

International Space Station Remote Sensing Pointing Analysis

NASA Technical Reports Server (NTRS)

Jacobson, Craig A.

2007-01-01

This paper analyzes the geometric and disturbance aspects of utilizing the International Space Station for remote sensing of earth targets. The proposed instrument (in prototype development) is SHORE (Station High-Performance Ocean Research Experiment), a multiband optical spectrometer with 15 m pixel resolution. The analysis investigates the contribution of the error effects to the quality of data collected by the instrument. This analysis supported the preliminary studies to determine feasibility of utilizing the International Space Station as an observing platform for a SHORE type of instrument. Rigorous analyses will be performed if a SHORE flight program is initiated. The analysis begins with the discussion of the coordinate systems involved and then conversion from the target coordinate system to the instrument coordinate system. Next the geometry of remote observations from the Space Station is investigated including the effects of the instrument location in Space Station and the effects of the line of sight to the target. The disturbance and error environment on Space Station is discussed covering factors contributing to drift and jitter, accuracy of pointing data and target and instrument accuracies.

The Concept and Analytical Investigation of CO2 and Steam Co-Electrolysis for Resource Utilization in Space Exploration

NASA Technical Reports Server (NTRS)

McKellar, Michael G.; Stoots, Carl M.; Sohal, Manohar S.; Mulloth, Lila M.; Luna, Bernadette; Abney, Morgan B.

2010-01-01

CO2 acquisition and utilization technologies will have a vital role in designing sustainable and affordable life support and in situ fuel production architectures for human and robotic exploration of Moon and Mars. For long-term human exploration to be practical, reliable technologies have to be implemented to capture the metabolic CO2 from the cabin air and chemically reduce it to recover oxygen. Technologies that enable the in situ capture and conversion of atmospheric CO2 to fuel are essential for a viable human mission to Mars. This paper describes the concept and mathematical analysis of a closed-loop life support system based on combined electrolysis of CO2 and steam (co-electrolysis). Products of the coelectrolysis process include oxygen and syngas (CO and H2) that are suitable for life support and synthetic fuel production, respectively. The model was developed based on the performance of a co-electrolysis system developed at Idaho National Laboratory (INL). Individual and combined process models of the co-electrolysis and Sabatier, Bosch, Boudouard, and hydrogenation reactions are discussed and their performance analyses in terms of oxygen production and CO2 utilization are presented.

Real-time experimental demonstrations of software reconfigurable optical OFDM transceivers utilizing DSP-based digital orthogonal filters for SDN PONs.

PubMed

Duan, X; Giddings, R P; Bolea, M; Ling, Y; Cao, B; Mansoor, S; Tang, J M

2014-08-11

Real-time optical OFDM (OOFDM) transceivers with on-line software-controllable channel reconfigurability and transmission performance adaptability are experimentally demonstrated, for the first time, utilizing Hilbert-pair-based 32-tap digital orthogonal filters implemented in FPGAs. By making use of an 8-bit DAC/ADC operating at 2GS/s, an oversampling factor of 2 and an EML intensity modulator, the demonstrated RF conversion-free transceiver supports end-to-end real-time simultaneous adaptive transmissions, within a 1GHz signal spectrum region, of a 2.03Gb/s in-phase OOFDM channel and a 1.41Gb/s quadrature-phase OOFDM channel over a 25km SSMF IMDD system. In addition, detailed experimental explorations are also undertaken of key physical mechanisms limiting the maximum achievable transmission performance, impacts of transceiver's channel multiplexing/demultiplexing operations on the system BER performance, and the feasibility of utilizing adaptive modulation to combat impairments associated with low-complexity digital filter designs. Furthermore, experimental results indicate that the transceiver incorporating a fixed digital orthogonal filter DSP architecture can be made transparent to various signal modulation formats up to 64-QAM.

Manatee lays groundwork for commercial use of Orimulsion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makansi, J.

1994-09-01

This article describes the conversion of an oil fired plant to Orimulsion described as a fourth fossil fuel, Orimulsion will replace oil at FP and L's Manatee station. The project involves unique business arrangements as well as important combustion, emissions control, and fuel handling system modifications. Florida Power and Light Co (FP and L) spent several years investigating the use of Orimulsion, including a full-scale five-months demonstration at its Sanford Station Unit 4. Now, the utility has taken the next giant leap; it has committed to convert the Manatee station for full-scale use of this unique fuel. The resulting projectmore » breaks new ground in the electric-generating business in several ways, including these: It represents the first long-term commercial contract for use of Orimulsion in the US, and the largest commitment world-wide. It involves unique business arrangements--not the least of which is the second major contract at an electric-utility station for a third-party-owned and operated flue-gas desulfurization (FGD) system. It indicates risk-taking on the part of utilities--with two 800-MW units, Manatee embodies a substantial amount of FP and L's total and incremental capacity base.« less

Experimental Research of a New Wave Energy Conversion Device

NASA Astrophysics Data System (ADS)

Lu, Zhongyue; Shang, Jianzhong; Luo, Zirong; Sun, Chongfei; Chen, Gewei

2018-01-01

With the increasing tension of contemporary social energy, the development and utilization of renewable energy has become an important development direction. As an important part of renewable energy, wave energy has the characteristics of green environmental protection and abundant reserves, attracting more investment and research. For small marine equipment energy supply problem, this paper puts forward a micro wave energy conversion device as the basic of heaving motion of waves in the ocean. This paper designed a new type of power output device can solve the micro wave energy conversion problem.

Silicon nanowires for photovoltaic solar energy conversion.

PubMed

Peng, Kui-Qing; Lee, Shuit-Tong

2011-01-11

Semiconductor nanowires are attracting intense interest as a promising material for solar energy conversion for the new-generation photovoltaic (PV) technology. In particular, silicon nanowires (SiNWs) are under active investigation for PV applications because they offer novel approaches for solar-to-electric energy conversion leading to high-efficiency devices via simple manufacturing. This article reviews the recent developments in the utilization of SiNWs for PV applications, the relationship between SiNW-based PV device structure and performance, and the challenges to obtaining high-performance cost-effective solar cells.

Graphene-based materials for energy conversion.

PubMed

Sahoo, Nanda Gopal; Pan, Yongzheng; Li, Lin; Chan, Siew Hwa

2012-08-08

With the depletion of conventional energy sources, the demand for renewable energy and energy-efficient devices continues to grow. As a novel 2D nanomaterial, graphene attracts considerable research interest due to its unique properties and is a promising material for applications in energy conversion and storage devices. Recently, the fabrication of fuel cells and solar cells using graphene for various functional parts has been studied extensively. This research news summarizes and compares the advancements that have been made and are in progress in the utilization of graphene-based materials for energy conversion.

AMTEC powered residential furnace and auxiliary power

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ivanenok, J.F. III; Sievers, R.K.

1996-12-31

Residential gas furnaces normally rely on utility grid electric power to operate the fans and/or the pumps used to circulate conditioned air or water and they are thus vulnerable to interruptions of utility grid service. Experience has shown that such interruptions can occur during the heating season, and can lead to serious consequences. A gas furnace coupled to an AMTEC conversion system retains the potential to produce heat and electricity (gas lines are seldom interrupted during power outages), and can save approximately $47/heating season compared to a conventional gas furnace. The key to designing a power system is understanding, andmore » predicting, the cell performance characteristics. The three main processes that must be understood and modeled to fully characterize an AMTEC cell are the electro-chemical, sodium vapor flow, and heat transfer. This paper will show the results of the most recent attempt to model the heat transfer in a multi-tube AMTEC cell and then discusses the conceptual design of a self-powered residential furnace.« less

Biological Conversion of Sugars to Hydrocarbons Technology Pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, R.; Biddy, M.; Tan, E.

2013-03-01

This technology pathway case investigates the biological conversion of biomass-derived sugars to hydrocarbon biofuels, utilizing data from recent literature references and information consistent with recent pilot-scale demonstrations at NREL. Technical barriers and key research needs have been identified that should be pursued for the pathway to become competitive with petroleum-derived gasoline-, diesel-, and jet-range hydrocarbon blendstocks.

The Socialization of Children's Memory: Linking Maternal Conversational Style to the Development of Children's Autobiographical and Deliberate Memory Skills

ERIC Educational Resources Information Center

Langley, Hillary A.; Coffman, Jennifer L.; Ornstein, Peter A.

2017-01-01

Data from a large-scale, longitudinal research study with an ethnically and socioeconomically diverse sample were utilized to explore linkages between maternal elaborative conversational style and the development of children's autobiographical and deliberate memory. Assessments were made when the children were aged 3, 5, and 6 years old, and the…

Biomass and Nitrogen Budgets During Larval Development of Lymantria dispar and Choristoneura fumiferana: Allometric Relationships

Treesearch

Michael E. Montgomery

1983-01-01

Spruce budworm larvae grew faster than gypsy moth larvae both in a temporal and relative sense. The budworm larvae had a higher relative growth rate (RGR), biomass conversion efficiency (EGI), and nitrogen utilization efficiency (NOE) than the gypsy moth larvae. As both species matured, relative growth rates, rates of consumption, and conversion efficiencies declined....

Design issues for grid-connected photovoltaic systems

NASA Astrophysics Data System (ADS)

Ropp, Michael Eugene

1998-08-01

Photovoltaics (PV) is the direct conversion of sunlight to electrical energy. In areas without centralized utility grids, the benefits of PV easily overshadow the present shortcomings of the technology. However, in locations with centralized utility systems, significant technical challenges remain before utility-interactive PV (UIPV) systems can be integrated into the mix of electricity sources. One challenge is that the needed computer design tools for optimal design of PV systems with curved PV arrays are not available, and even those that are available do not facilitate monitoring of the system once it is built. Another arises from the issue of islanding. Islanding occurs when a UIPV system continues to energize a section of a utility system after that section has been isolated from the utility voltage source. Islanding, which is potentially dangerous to both personnel and equipment, is difficult to prevent completely. The work contained within this thesis targets both of these technical challenges. In Task 1, a method for modeling a PV system with a curved PV array using only existing computer software is developed. This methodology also facilitates comparison of measured and modeled data for use in system monitoring. The procedure is applied to the Georgia Tech Aquatic Center (GTAC) FV system. In the work contained under Task 2, islanding prevention is considered. The existing state-of-the- art is thoroughly reviewed. In Subtask 2.1, an analysis is performed which suggests that standard protective relays are in fact insufficient to guarantee protection against islanding. In Subtask 2.2. several existing islanding prevention methods are compared in a novel way. The superiority of this new comparison over those used previously is demonstrated. A new islanding prevention method is the subject under Subtask 2.3. It is shown that it does not compare favorably with other existing techniques. However, in Subtask 2.4, a novel method for dramatically improving this new islanding prevention method is described. It is shown, both by computer modeling and experiment, that this new method is one of the most effective available today. Finally, under Subtask 2.5, the effects of certain types of loads; on the effectiveness of islanding prevention methods are discussed.

Heat Transfer Phenomena in Concentrating Solar Power Systems.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Armijo, Kenneth Miguel; Shinde, Subhash L.

Concentrating solar power (CSP) utilizes solar thermal energy to drive a thermal power cycle for the generation of electricity. CSP systems are facilitated as large, centralized power plants , such as power towers and trough systems, to take advantage of ec onomies of scale through dispatchable thermal energy storage, which is a principle advantage over other energy generation systems . Additionally, the combination of large solar concentration ratios with high solar conversion efficiencies provides a strong o pportunity of employment of specific power cycles such as the Brayton gas cycle that utilizes super critical fluids such as supercritical carbon dioxidemore » (s CO 2 ) , compared to other sola r - fossil hybrid power plants. A comprehensive thermal - fluids examination is provided by this work of various heat transfer phenomena evident in CSP technologies. These include sub - systems and heat transfer fundamental phenomena evident within CSP systems , which include s receivers, heat transfer fluids (HTFs), thermal storage me dia and system designs , thermodynamic power block systems/components, as well as high - temperature materials. This work provides literature reviews, trade studies, and phenomenological comparisons of heat transfer media (HTM) and components and systems, all for promotion of high performance and efficient CSP systems. In addition, f urther investigations are also conducted that provide advanced heat transfer modeling approaches for gas - particle receiver systems , as well as performance/efficiency enhancement re commendations, particularly for solarized supercritical power systems .« less

High voltage systems (tube-type microwave)/low voltage system (solid-state microwave) power distribution

NASA Technical Reports Server (NTRS)

Nussberger, A. A.; Woodcock, G. R.

1980-01-01

SPS satellite power distribution systems are described. The reference Satellite Power System (SPS) concept utilizes high-voltage klystrons to convert the onboard satellite power from dc to RF for transmission to the ground receiving station. The solar array generates this required high voltage and the power is delivered to the klystrons through a power distribution subsystem. An array switching of solar cell submodules is used to maintain bus voltage regulation. Individual klystron dc voltage conversion is performed by centralized converters. The on-board data processing system performs the necessary switching of submodules to maintain voltage regulation. Electrical power output from the solar panels is fed via switch gears into feeder buses and then into main distribution buses to the antenna. Power also is distributed to batteries so that critical functions can be provided through solar eclipses.

ProcessGene-Connect: SOA Integration between Business Process Models and Enactment Transactions of Enterprise Software Systems

NASA Astrophysics Data System (ADS)

Wasser, Avi; Lincoln, Maya

In recent years, both practitioners and applied researchers have become increasingly interested in methods for integrating business process models and enterprise software systems through the deployment of enabling middleware. Integrative BPM research has been mainly focusing on the conversion of workflow notations into enacted application procedures, and less effort has been invested in enhancing the connectivity between design level, non-workflow business process models and related enactment systems such as: ERP, SCM and CRM. This type of integration is useful at several stages of an IT system lifecycle, from design and implementation through change management, upgrades and rollout. The paper presents an integration method that utilizes SOA for connecting business process models with corresponding enterprise software systems. The method is then demonstrated through an Oracle E-Business Suite procurement process and its ERP transactions.

ECUT: Energy Conversion and Utilization Technologies program. Industry, university and research interest in the US Department of Energy ECUT biocatalysis research activity

NASA Technical Reports Server (NTRS)

Wilcox, R. E.

1983-01-01

The results of a Research Opportunity Notice (RON) disseminated by the Jet Propulsion Laboratory for the U.S. Department of Energy Conversion and Utilization Technologies (ECUT) Program's Biocatalysis Research Activity are presented. The RON was issued in late April of 1983 and solicited expressions of interest from petrochemical and chemical companies, bioengineering firms, biochemical engineering consultants, private research laboratories, and universities for participating in a federal research program to investigate potential applications of biotechnology in producing chemicals. The RON results indicate that broad interest exists within the nation's industry, universities, and research institutes for the Activity and its planned research and development program.

Efficient Solar Energy Harvesting and Storage through a Robust Photocatalyst Driving Reversible Redox Reactions.

PubMed

Zhou, Yangen; Zhang, Shun; Ding, Yu; Zhang, Leyuan; Zhang, Changkun; Zhang, Xiaohong; Zhao, Yu; Yu, Guihua

2018-06-14

Simultaneous solar energy conversion and storage is receiving increasing interest for better utilization of the abundant yet intermittently available sunlight. Photoelectrodes driving nonspontaneous reversible redox reactions in solar-powered redox cells (SPRCs), which can deliver energy via the corresponding reverse reactions, present a cost-effective and promising approach for direct solar energy harvesting and storage. However, the lack of photoelectrodes having both high conversion efficiency and high durability becomes a bottleneck that hampers practical applications of SPRCs. Here, it is shown that a WO 3 -decorated BiVO 4 photoanode, without the need of extra electrocatalysts, can enable a single-photocatalyst-driven SPRC with a solar-to-output energy conversion efficiency as high as 1.25%. This SPRC presents stable performance over 20 solar energy storage/delivery cycles. The high efficiency and stability are attributed to the rapid redox reactions, the well-matched energy level, and the efficient light harvesting and charge separation of the prepared BiVO 4 . This demonstrated device system represents a potential alternative toward the development of low-cost, durable, and easy-to-implement solar energy technologies. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of a decision model for the techno-economic assessment of municipal solid waste utilization pathways.

PubMed

Khan, Md Mohib-Ul-Haque; Jain, Siddharth; Vaezi, Mahdi; Kumar, Amit

2016-02-01

Economic competitiveness is one of the key factors in making decisions towards the development of waste conversion facilities and devising a sustainable waste management strategy. The goal of this study is to develop a framework, as well as to develop and demonstrate a comprehensive techno-economic model to help county and municipal decision makers in establishing waste conversion facilities. The user-friendly data-intensive model, called the FUNdamental ENgineering PrinciplEs-based ModeL for Estimation of Cost of Energy and Fuels from MSW (FUNNEL-Cost-MSW), compares nine different waste management scenarios, including landfilling and composting, in terms of economic parameters such as gate fees and return on investment. In addition, a geographic information system (GIS) model was developed to determine suitable locations for waste conversion facilities and landfill sites based on integration of environmental, social, and economic factors. Finally, a case study on Parkland County and its surrounding counties in the province of Alberta, Canada, was conducted and a sensitivity analysis was performed to assess the influence of the key technical and economic parameters on the calculated results. Copyright © 2015 Elsevier Ltd. All rights reserved.

Deciphering visible light photoreductive conversion of CO2 to formic acid and methanol using waste prepared material.

PubMed

Zhang, Qian; Lin, Cheng-Fang; Chen, Bor-Yann; Ouyang, Tong; Chang, Chang-Tang

2015-02-17

As gradual increases in atmospheric CO2 and depletion of fossil fuels have raised considerable public concern in recent decades, utilizing the unlimited solar energy to convert CO2 to fuels (e.g., formic acid and methanol) apparently could simultaneously resolve these issues for sustainable development. However, due to the complicated characteristics of CO2 reduction, the mechanism has yet to be disclosed. To clarify the postulated pathway as mentioned in the literature, the technique of electron paramagnetic resonance (ESR) was implemented herein to confirm the mechanism and related pathways of CO2 reduction under visible light using graphene-TiO2 as catalyst. The findings indicated that CO(-•) radicals, as the main intermediates, were first detected herein to react with several hydrogen ions and electrons for the formation of CH3OH. For example, the generation of CO(-•) radicals is possibly the vital rate-controlling step for conversion of CO2 to methanol as hypothesized elsewhere. The kinetics behind the proposed mechanism was also determined in this study. The mechanism and kinetics could provide the in-depth understanding to the pathway of CO2 reduction and disclose system optimization of maximal conversion for further application.

Grid-connected integrated community energy system. Phase II, Stage 2, final report. Preliminary design pyrolysis facility. [Andco-Torrax system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The University of Minnesota is studying and planning a grid connected integrated community energy system to include disposal of wastes from health centers and utilizing the heat generated. The University of Minnesota has purchased the so called Southeast Generating Station from the Northern States Power Company. This plant contains two coal-fired boilers that will be retrofitted to burn low-sulfur Montana coal. Building modifications and additions will be made to support the components of the Andco-Torrax system and integrate the system with the rest of the plant. The Andco-Torrax system is a new high-temperature refuse-conversion process known technically as slagging pyrolysis.more » Although the pyrolysis of solid waste is a relatively new innovation, pyrolysis processes have been used for years by industry. This report covers the preliminary design and operation of the system. (MCW)« less

Life sciences Spacelab Mission Development test 3 (SMD 3) data management report

NASA Technical Reports Server (NTRS)

Moseley, E. C.

1977-01-01

Development of a permanent data system for SMD tests was studied that would simulate all elements of the shuttle onboard, telemetry, and ground data systems that are involved with spacelab operations. The onboard data system (ODS) and the ground data system (GDS) were utilized. The air-to-ground link was simulated by a hardwired computer-to-computer interface. A patch board system was used on board to select experiment inputs, and the downlink configuration from the ODS was changed by a crew keyboard entry to support each experiment. The ODS provided a CRT display of experiment parameters to enable the crew to monitor experiment performance. An onboard analog system, with recording capability, was installed to handle high rate data and to provide a backup to the digital system. The GDS accomplished engineering unit conversion and limit sensing, and provided realtime parameter display on CRT's in the science monitoring area and the test control area.

Analog to digital workflow improvement: a quantitative study.

PubMed

Wideman, Catherine; Gallet, Jacqueline

2006-01-01

This study tracked a radiology department's conversion from utilization of a Kodak Amber analog system to a Kodak DirectView DR 5100 digital system. Through the use of ProModel Optimization Suite, a workflow simulation software package, significant quantitative information was derived from workflow process data measured before and after the change to a digital system. Once the digital room was fully operational and the radiology staff comfortable with the new system, average patient examination time was reduced from 9.24 to 5.28 min, indicating that a higher patient throughput could be achieved. Compared to the analog system, chest examination time for modality specific activities was reduced by 43%. The percentage of repeat examinations experienced with the digital system also decreased to 8% vs. the level of 9.5% experienced with the analog system. The study indicated that it is possible to quantitatively study clinical workflow and productivity by using commercially available software.

Advanced laser architectures for high power eyesafe illuminators

NASA Astrophysics Data System (ADS)

Baranova, N.; Pati, B.; Stebbins, K.; Bystryak, I.; Rayno, M.; Ezzo, K.; DePriest, C.

2018-02-01

Q-Peak has demonstrated a novel pulsed eyesafe laser architecture operating with >50 mJ pulse energies at Pulse Repetition Frequencies (PRFs) as high as 320 Hz. The design leverages an Optical Parametric Oscillator (OPO) and Optical Parametric Amplifier (OPA) geometry, which provides the unique capability for high power in a comparatively compact package, while also offering the potential for additional eyesafe power scaling. The laser consists of a Commercial Off-the-Shelf (COTS) Q-switched front-end seed laser to produce pulse-widths around 10 ns at 1.06-μm, which is then followed by a pair of Multi-Pass Amplifier (MPA) architectures (comprised of side-pumped, multi-pass Nd:YAG slabs with a compact diode-pump-array imaging system), and finally involving two sequential nonlinear optical conversion architectures for transfer into the eyesafe regime. The initial seed beam is first amplified through the MPA, and then split into parallel optical paths. An OPO provides effective nonlinear conversion on one optical path, while a second MPA further amplifies the 1.06-μm beam for use in pumping an OPA on the second optical path. These paths are then recombined prior to seeding the OPA. Each nonlinear conversion subsystem utilizes Potassium Titanyl Arsenate (KTA) for effective nonlinear conversion with lower risk to optical damage. This laser architecture efficiently produces pulse energies of >50 mJ in the eyesafe band at PRFs as high as 320 Hz, and has been designed to fit within a volume of 4,500 in3 (0.074 m3 ). We will discuss theoretical and experimental details of the nonlinear optical system for achieving higher eyesafe powers.

Strategic planning--a plan for excellence for South Haven Health System.

PubMed

Urbanski, Joanne; Baskel, Maureen; Martelli, Mary

2011-01-01

South Haven Health System has developed an innovative approach to strategic planning. The key to success of this process has been the multidisciplinary involvement of all stakeholders from the first planning session through the final formation of a strategic plan with measurable objectives for each goal. The process utilizes a Conversation Café method for identifying opportunities and establishing goals, Strategic Oversight Teams to address each goal and a Champion for implementation of each objective. Progress is measured quarterly by Strategic Oversight Team report cards. Transparency of communication within the organization and the sharing of information move the plan forward. The feedback from participant evaluations has been overwhelmingly positive. They are involved and excited.

OTEC to hydrogen fuel cells - A solar energy breakthrough

NASA Astrophysics Data System (ADS)

Roney, J. R.

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

Charming Users into Scripting CIAO with Python

NASA Astrophysics Data System (ADS)

Burke, D. J.

2011-07-01

The Science Data Systems group of the Chandra X-ray Center provides a number of scripts and Python modules that extend the capabilities of CIAO. Experience in converting the existing scripts—written in a variety of languages such as bash, csh/tcsh, Perl and S-Lang—to Python, and conversations with users, led to the development of the ciao_contrib.runtool module. This allows users to easily run CIAO tools from Python scripts, and utilizes the metadata provided by the parameter-file system to create an API that provides the flexibility and safety guarantees of the command-line. The module is provided to the user community and is being used within our group to create new scripts.

Optical computing using optical flip-flops in Fourier processors: use in matrix multiplication and discrete linear transforms.

PubMed

Ando, S; Sekine, S; Mita, M; Katsuo, S

1989-12-15

An architecture and the algorithms for matrix multiplication using optical flip-flops (OFFs) in optical processors are proposed based on residue arithmetic. The proposed system is capable of processing all elements of matrices in parallel utilizing the information retrieving ability of optical Fourier processors. The employment of OFFs enables bidirectional data flow leading to a simpler architecture and the burden of residue-to-decimal (or residue-to-binary) conversion to operation time can be largely reduced by processing all elements in parallel. The calculated characteristics of operation time suggest a promising use of the system in a real time 2-D linear transform.

RETHINKING THE FUTURE GRID: INTEGRATED NUCLEAR-RENEWABLE ENERGY SYSTEMS

DOE Office of Scientific and Technical Information (OSTI.GOV)

S.M. Bragg-Sitton; R. Boardman

2014-12-01

The 2013 electricity generation mix in the United States consisted of ~13% renewables (hydropower, wind, solar, geothermal), 19% nuclear, 27% natural gas, and 39% coal. In the 2011 State of the Union Address, President Obama set a clean energy goal for the nation: “By 2035, 80 percent of America’s electricity will come from clean energy sources. Some folks want wind and solar. Others want nuclear, clean coal and natural gas. To meet this goal we will need them all.” The U.S. Department of Energy (DOE) Offices of Nuclear Energy (NE) and Energy Efficiency and Renewable Energy (EERE) recognize that “allmore » of the above” means that we are called to best utilize all available clean energy sources. To meet the stated environmental goals for electricity generation and for the broader energy sector, there is a need to transform the energy infrastructure of the U.S. and elsewhere. New energy systems must be capable of significantly reducing environmental impacts in an efficient and economically viable manner while utilizing both hydrocarbon resources and clean energy generation sources. The U.S. DOE is supporting research and development that could lead to more efficient utilization of clean energy generation sources, including renewable and nuclear options, to meet both grid demand and thermal energy needs in the industrial sector. A concept being advanced by the DOE-NE and DOE-EERE is tighter coupling of nuclear and renewable energy sources in a manner that better optimizes energy use for the combined electricity, industrial manufacturing, and the transportation sectors. This integration concept has been referred to as a “hybrid system” that is capable of apportioning thermal and electrical energy to first meet the grid demand (with appropriate power conversion systems), then utilizing excess thermal and, in some cases, electrical energy to drive a process that results in an additional product. For the purposes of the present work, the hybrid system would integrate two or more energy resources to generate two or more products, one of which must be an energy commodity, such as electricity or transportation fuel. Subsystems would be integrated ‘‘behind’’ the electrical transmission bus and would be comprised of two or more energy conversion subsystems that have traditionally been separate or isolated. Energy flows would be dynamically apportioned as necessary to meet grid demand via a single, highly responsive connection to the grid that provides dispatchable electricity while capital-intensive generation assets operate at full capacity. Candidate region-specific hybrid energy systems selected for further study and figures of merit that will be used to assess system performance will be presented.« less

Design considerations for space radiators based on the liquid sheet (LSR) concept

NASA Technical Reports Server (NTRS)

Juhasz, Albert J.; Chubb, Donald L.

1991-01-01

Concept development work on space heat rejection subsystems tailored to the requirements of various space power conversion systems is proceeding over a broad front of technologies at NASA LeRC. Included are orbital and planetary surface based radiator concepts utilizing pumped loops, a variety of heat pipe radiator concepts, and the innovative liquid sheet radiator (LSR). The basic feasibility of the LSR concept was investigated in prior work which generated preliminary information indicating the suitability of the LSR concept for space power systems requiring cycle reject heat to be radiated to the space sink at low-to-mid temperatures (300 to 400 K), with silicon oils used for the radiator working fluid. This study is directed at performing a comparative examination of LSR characteristics as they affect the basic design of low earth orbit solar dynamic power conversion systems. The power systems considered were based on the closed Brayton (CBC) and the Free Piston Stirling (FPS) cycles, each with a power output of 2 kWe and using previously tested silicone oil (Dow-Corning Me2) as the radiator working fluid. Conclusions indicate that, due to its ability for direct cold end cooling, an LSR based heat rejection subsystem is far more compatible with a Stirling space power system than with a CBC, which requires LSR coupling by means of an intermediate gas/liquid heat exchanger and adjustment of cycle operating conditions.

Demonstrating Hybrid Heat Transport and Energy Conversion System Performance Characterization Using Intelligent Control Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ostrum, Lee; Manic, Milos

The debate continues on the magnitude and validity of climate change caused by human activities. However, there is no debate about the need to make buildings, modes of transportation, factories, and homes as energy efficient as possible. Given that climate change could occur with the wasteful use of fossil fuel and the fact that fossil energy costs could and will swing wildly, it is imperative that every effort be made to utilize energy sources to their fullest. Hybrid energy systems (HES) are two or more separate energy producers used together to produce energy commodities. The HES this report focuses onmore » is the use of nuclear reactor waste heat as a source of further energy utilization. Nuclear reactors use a fluid to cool the core and produce the steam needed for the production of electricity. Traditionally this steam, or coolant, is used to convert the energy then cooled elsewhere. The heat is released into the environment without being used further. By adding technologies to nuclear reactors to use the wasted heat, a system can be developed to make more than just electricity and allow for loading following capabilities.« less

Unlocking the potential of SnS2: Transition metal catalyzed utilization of reversible conversion and alloying reactions

NASA Astrophysics Data System (ADS)

Huang, Zhi Xiang; Wang, Ye; Liu, Bo; Kong, Dezhi; Zhang, Jun; Chen, Tupei; Yang, Hui Ying

2017-01-01

The alloying-dealloying reactions of SnS2 proceeds with the initial conversion reaction of SnS2 with lithium that produces Li2S. Unfortunately, due to the electrochemical inactivity of Li2S, the conversion reaction of SnS2 is irreversible, which significantly limit its potential applications in lithium-ion batteries. Herein, a systematic understanding of transition metal molybdenum (Mo) as a catalyst in SnS2 anode is presented. It is found that Mo catalyst is able to efficiently promote the reversible conversion of Sn to SnS2. This leads to the utilization of both conversion and alloying reactions in SnS2 that greatly increases lithium storage capability of SnS2. Mo catalyst is introduced in the form of MoS2 grown directly onto self-assembled vertical SnS2 nanosheets that anchors on three-dimensional graphene (3DG) creating a hierarchal nanostructured named as SnS2/MoS2/3DG. The catalytic effect results in a significantly enhanced electrochemical properties of SnS2/MoS2/3DG; a high initial Coulombic efficiency (81.5%) and high discharge capacities of 960.5 and 495.6 mA h g-1 at current densities of 50 and 1000 mA g-1, respectively. Post cycling investigations using ex situ TEM and XPS analysis verifies the successful conversion reaction of SnS2 mediated by Mo. The successful integration of catalyst on alloying type metal sulfide anode creates a new avenue towards high energy density lithium anodes.

Unlocking the potential of SnS2: Transition metal catalyzed utilization of reversible conversion and alloying reactions.

PubMed

Huang, Zhi Xiang; Wang, Ye; Liu, Bo; Kong, Dezhi; Zhang, Jun; Chen, Tupei; Yang, Hui Ying

2017-01-19

The alloying-dealloying reactions of SnS 2 proceeds with the initial conversion reaction of SnS 2 with lithium that produces Li 2 S. Unfortunately, due to the electrochemical inactivity of Li 2 S, the conversion reaction of SnS 2 is irreversible, which significantly limit its potential applications in lithium-ion batteries. Herein, a systematic understanding of transition metal molybdenum (Mo) as a catalyst in SnS 2 anode is presented. It is found that Mo catalyst is able to efficiently promote the reversible conversion of Sn to SnS 2 . This leads to the utilization of both conversion and alloying reactions in SnS 2 that greatly increases lithium storage capability of SnS 2 . Mo catalyst is introduced in the form of MoS 2 grown directly onto self-assembled vertical SnS 2 nanosheets that anchors on three-dimensional graphene (3DG) creating a hierarchal nanostructured named as SnS 2 /MoS 2 /3DG. The catalytic effect results in a significantly enhanced electrochemical properties of SnS 2 /MoS 2 /3DG; a high initial Coulombic efficiency (81.5%) and high discharge capacities of 960.5 and 495.6 mA h g -1 at current densities of 50 and 1000 mA g -1 , respectively. Post cycling investigations using ex situ TEM and XPS analysis verifies the successful conversion reaction of SnS 2 mediated by Mo. The successful integration of catalyst on alloying type metal sulfide anode creates a new avenue towards high energy density lithium anodes.

Correcting the thermal inefficiencies of a cogeneration and boiler plant by low-pressure steam conversions and hot water thermal energy storage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pals, C.M.

1998-12-31

A liberal arts college in Los Angeles was plagued by inefficient use of low-pressure (LP) steam produced by its two 150 kWe cogeneration units. Poor integration of the LP cogen system into the college`s existing high-pressure (HP) steam boiler plant led to under-utilization of cogenerated steam during the non-space-heating season. Six years of inefficient operation was estimated to have cost the college $750,000 in lost utility and maintenance savings. To improve steam-plant operations, the college`s facilities management staff implemented a plan to convert HP steam loads to LP, replace HP steam boilers with LP equipment, and improve the use ofmore » cogenerated steam through the installation of a hot water thermal energy storage (TES) system. A study was commissioned that identified the plant`s peak winter steam requirements and the typical steam profile for the non-space-heating season. Data from this work helped draw two conclusions: (1) converting HP steam loads to LP would boost demand for cogenerated steam, and (2) a hot water thermal energy storage (TES) system could further utilize a portion of remaining excess cogen steam for the manufacture and storage of the kitchen`s domestic water for use during peak steam demand periods. Combined, these two measures were estimated to improve utilization of cogenerated LP steam by 11,000 pounds (5,000 kg) per day and reduce boiler fuel consumption by 40,000 therms (4,220,000 MJ) each season. In addition to this work, a major plant renovation project was completed, which included the replacement of a 60-year-old, 280 bhp (2,747 kW) HP steam boiler, with two new LP boilers. Conversion to LP and the start-up of the hot water TES was completed in May 1997. During the first year of operation, after the improvement, boiler gas savings exceeded 52,000 therms (5,486,000 MJ). Maintenance savings of $100,000 were also accrued by eliminating licensed HP boiler operators. All construction work described to improve energy efficiency and rehabilitate the steam plant cost $687,000 and is on track to produce a simple payback of 5.5 years. Overall, this paper demonstrates the energy and cost inefficiencies that may result if the opportunities to use waste heat from cogeneration systems are incorrectly identified.« less

Power control and management of the grid containing largescale wind power systems

NASA Astrophysics Data System (ADS)

Aula, Fadhil Toufick

The ever increasing demand for electricity has driven many countries toward the installation of new generation facilities. However, concerns such as environmental pollution and global warming issues, clean energy sources, high costs associated with installation of new conventional power plants, and fossil fuels depletion have created many interests in finding alternatives to conventional fossil fuels for generating electricity. Wind energy is one of the most rapidly growing renewable power sources and wind power generations have been increasingly demanded as an alternative to the conventional fossil fuels. However, wind power fluctuates due to variation of wind speed. Therefore, large-scale integration of wind energy conversion systems is a threat to the stability and reliability of utility grids containing these systems. They disturb the balance between power generation and consumption, affect the quality of the electricity, and complicate load sharing and load distribution managing and planning. Overall, wind power systems do not help in providing any services such as operating and regulating reserves to the power grid. In order to resolve these issues, research has been conducted in utilizing weather forecasting data to improve the performance of the wind power system, reduce the influence of the fluctuations, and plan power management of the grid containing large-scale wind power systems which consist of doubly-fed induction generator based energy conversion system. The aims of this research, my dissertation, are to provide new methods for: smoothing the output power of the wind power systems and reducing the influence of their fluctuations, power managing and planning of a grid containing these systems and other conventional power plants, and providing a new structure of implementing of latest microprocessor technology for controlling and managing the operation of the wind power system. In this research, in order to reduce and smooth the fluctuations, two methods are presented. The first method is based on a de-loaded technique while the other method is based on utilizing multiple storage facilities. The de-loaded technique is based on characteristics of the power of a wind turbine and estimation of the generated power according to weather forecasting data. The technique provides a reference power by which the wind power system will operate and generate a smooth power. In contrast, utilizing storage facilities will allow the wind power system to operate at its maximum tracking power points' strategy. Two types of energy storages are considered in this research, battery energy storage system (BESS) and pumped-hydropower storage system (PHSS), to suppress the output fluctuations and to support the wind power system to follow the system load demands. Furthermore, this method provides the ability to store energy when there is a surplus of the generated power and to reuse it when there is a shortage of power generation from wind power systems. Both methods are new in terms of utilizing of the techniques and wind speed data. A microprocessor embedded system using an IntelRTM Atom(TM) processor is presented for controlling the wind power system and for providing the remote communication for enhancing the operation of the individual wind power system in a wind farm. The embedded system helps the wind power system to respond and to follow the commands of the central control of the power system. Moreover, it enhances the performance of the wind power system through self-managing, self-functioning, and self-correcting. Finally, a method of system power management and planning is modeled and studied for a grid containing large-scale wind power systems. The method is based on a new technique through constructing a new load demand curve (NLDC) from merging the estimation of generated power from wind power systems and forecasting of the load. To summarize, the methods and their results presented in this dissertation, enhance the operation of the large-scale wind power systems and reduce their drawbacks on the operation of the power grid.

Computer-Assisted English Learning System Based on Free Conversation by Topic

ERIC Educational Resources Information Center

Choi, Sung-Kwon; Kwon, Oh-Woog; Kim, Young-Kil

2017-01-01

This paper aims to describe a computer-assisted English learning system using chatbots and dialogue systems, which allow free conversation outside the topic without limiting the learner's flow of conversation. The evaluation was conducted by 20 experimenters. The performance of the system based on a free conversation by topic was measured by the…

Solar powered Stirling cycle electrical generator

NASA Technical Reports Server (NTRS)

Shaltens, Richard K.

1991-01-01

Under NASA's Civil Space Technology Initiative (CSTI), the NASA Lewis Research Center is developing the technology needed for free-piston Stirling engines as a candidate power source for space systems in the late 1990's and into the next century. Space power requirements include high efficiency, very long life, high reliability, and low vibration. Furthermore, system weight and operating temperature are important. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, non-contacting gas bearings, and can be hermetically sealed. These attributes of the free-piston Stirling engine also make it a viable candidate for terrestrial applications. In cooperation with the Department of Energy, system designs are currently being completed that feature the free-piston Stirling engine for terrestrial applications. Industry teams were assembled and are currently completing designs for two Advanced Stirling Conversion Systems utilizing technology being developed under the NASA CSTI Program. These systems, when coupled with a parabolic mirror to collect the solar energy, are capable of producing about 25 kW of electricity to a utility grid. Industry has identified a niche market for dish Stirling systems for worldwide remote power application. They believe that these niche markets may play a major role in the introduction of Stirling products into the commercial market.

Optimized Wavelength-Tuned Nonlinear Frequency Conversion Using a Liquid Crystal Clad Waveguide

NASA Technical Reports Server (NTRS)

Stephen, Mark A. (Inventor)

2018-01-01

An optimized wavelength-tuned nonlinear frequency conversion process using a liquid crystal clad waveguide. The process includes implanting ions on a top surface of a lithium niobate crystal to form an ion implanted lithium niobate layer. The process also includes utilizing a tunable refractive index of a liquid crystal to rapidly change an effective index of the lithium niobate crystal.

OTEC platform configuration and integration study. Volume I. Systems engineering and integration. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1978-04-01

The economic success of an Ocean Thermal Energy Conversion (OTEC) system is highly dependent on a platform which provides adequate support for the power system, accommodates reliably the cold water pipe, and is most cost effective. The results of a study conducted for the Department of Energy to assess six generic types of platforms to determine the most satisfactory platform for severl potential sites are presented. The six platform configurations are ship, circular barge, semi-submersible, Tuned Sphere, submersible, and spar. These represent directional and symmetric types of platforms which operate on the surface, at the interface, and submerged. The fivemore » sites for this study were primarily New Orleans, Keahole Point (Hawaii), Brazil, and secondarily Key West and Puerto Rico. Electrical transmission of energy by submarine cable is the planned form of energy transmission for all sites except Brazil, where chemical conversion is to be the method of transmission. This study is devoted to the platform (or ocean systems) of the OTEC plant which is chiefly comprised of the hull and structure, the seawater system, the position control system, and miscellaneous support/assembly systems. The principal elements in the work breakdown structure for the commercial plants are presented. The assessment of the six platform configurations was conducted utilizing a baseline plan (100-MW(e) (Net)) and site (New Orleans) with variations from the baseline to cover the range of interested platforms and sites.« less

Linguistic Input, Electronic Media, and Communication Outcomes of Toddlers with Hearing Loss

PubMed Central

Ambrose, Sophie E.; VanDam, Mark; Moeller, Mary Pat

2013-01-01

Objectives The objectives of this study were to examine the quantity of adult words, adult-child conversational turns, and electronic media in the auditory environments of toddlers who are hard of hearing (HH) and to examine whether these variables contributed to variability in children’s communication outcomes. Design Participants were 28 children with mild to severe hearing loss. Full-day recordings of children’s auditory environments were collected within 6 months of their 2nd birthdays by utilizing LENA (Language ENvironment Analysis) technology. The system analyzes full-day acoustic recordings, yielding estimates of the quantity of adult words, conversational turns, and electronic media exposure in the recordings. Children’s communication outcomes were assessed via the receptive and expressive scales of the Mullen Scales of Early Learning at 2 years of age and the Comprehensive Assessment of Spoken Language at 3 years of age. Results On average, the HH toddlers were exposed to approximately 1400 adult words per hour and participated in approximately 60 conversational turns per hour. An average of 8% of each recording was classified as electronic media. However, there was considerable within-group variability on all three measures. Frequency of conversational turns, but not adult words, was positively associated with children’s communication outcomes at 2 and 3 years of age. Amount of electronic media exposure was negatively associated with 2-year-old receptive language abilities; however, regression results indicate that the relationship was fully mediated by the quantity of conversational turns. Conclusions HH toddlers who were engaged in more conversational turns demonstrated stronger linguistic outcomes than HH toddlers who were engaged in fewer conversational turns. The frequency of these interactions was found to be decreased in households with high rates of electronic media exposure. Optimal language-learning environments for HH toddlers include frequent linguistic interactions between parents and children. To support this goal, parents should be encouraged to reduce their children’s exposure to electronic media. PMID:24441740

Creating Critical Conversations: Investigating the Utility of Socratic Dialogues in Elementary Social Studies Methods

ERIC Educational Resources Information Center

Buchanan, Lisa Brown

2012-01-01

This article explores the utility of Socratic dialogues in the elementary social studies methods course. Findings include preservice teachers' behaviors during dialogues, perceived strengths and challenges of using Socratic dialogues in teacher education, and the impact on student learning. Challenges and apprehensions encountered by the teacher…

Bark And Its Possible Uses

Treesearch

J. M. Harkin; J. W. Rowe

1971-01-01

What to do with bark is a major question facing the wood conversion industries. Optimum utilization of bark residues demands appreciation of the complexity of bark and the extreme variation in chemical and physical properties between barks of different wood species. This report discusses bark structure, past and present utilization, and methods of upgrading bark both...

Understanding the emission impacts of high-occupancy vehicle (HOV) to high-occupancy toll (HOT) lane conversions: Experience from Atlanta, Georgia.

PubMed

Xu, Yanzhi Ann; Liu, Haobing; Rodgers, Michael O; Guin, Angshuman; Hunter, Michael; Sheikh, Adnan; Guensler, Randall

2017-08-01

Converting a congested high-occupancy vehicle (HOV) lane into a high-occupancy toll (HOT) lane is a viable option for improving travel time reliability for carpools and buses that use the managed lane. However, the emission impacts of HOV-to-HOT conversions are not well understood. The lack of emission impact quantification for HOT conversions creates a policy challenge for agencies making transportation funding choices. The goal of this paper is to evaluate the case study of before-and-after changes in vehicle emissions for the Atlanta, Georgia, I-85 HOV/HOT lane conversion project, implemented in October 2011. The analyses employed the Motor Vehicle Emission Simulator (MOVES) for project-level analysis with monitored changes in vehicle activity data collected by Georgia Tech researchers for the Georgia Department of Transportation (GDOT). During the quarterly field data collection from 2010 to 2012, more than 1.5 million license plates were observed and matched to vehicle class and age information using the vehicle registration database. The study also utilized the 20-sec, lane-specific traffic operations data from the Georgia NaviGAtor intelligent transportation system, as well as a direct feed of HOT lane usage data from the State Road and Tollway Authority (SRTA) managed lane system. As such, the analyses in this paper simultaneously assessed the impacts associated with changes in traffic volumes, on-road operating conditions, and fleet composition before and after the conversion. Both greenhouse gases and criteria pollutants were examined. A straight before-after analysis showed about 5% decrease in air pollutants and carbon dioxide (CO 2 ). However, when the before-after calendar year of analysis was held constant (to account for the effect of 1 yr of fleet turnover), mass emissions at the analysis site during peak hours increased by as much as 17%, with little change in CO 2 . Further investigation revealed that a large percentage decrease in criteria pollutants in the straight before-after analysis was associated with a single calendar year change in MOVES. Hence, the Atlanta, Georgia, results suggest that an HOV-to-HOT conversion project may have increased mass emissions on the corridor. The results also showcase the importance of obtaining on-road data for emission impact assessment of HOV-to-HOT conversion projects.

Electroviscous effect and electrokinetic energy conversion in time periodic pressure-driven flow through a parallel-plate nanochannel with surface charge-dependent slip

NASA Astrophysics Data System (ADS)

Buren, Mandula; Jian, Yongjun; Zhao, Yingchun; Chang, Long

2018-05-01

In this paper we analytically investigate the electroviscous effect and electrokinetic energy conversion in the time periodic pressure-driven flow of an incompressible viscous Newtonian liquid through a parallel-plate nanochannel with surface charge-dependent slip. Analytical and semi-analytical solutions for electric potential, velocity and streaming electric field are obtained and are utilized to compute electrokinetic energy conversion efficiency. The results show that velocity amplitude and energy conversion efficiency are reduced when the effect of surface charge on slip length is considered. The surface charge effect increases with zeta potential and ionic concentration. In addition, the energy conversion efficiency is large when the ratio of channel half-height to the electric double layer thickness is small. The boundary slip results in a large increase in energy conversion. Higher values of the frequency of pressure pulsation lead to higher values of the energy conversion efficiency. We also obtain the energy conversion efficiency in constant pressure-driven flow and find that the energy conversion efficiency in periodical pressure-driven flow becomes larger than that in constant pressure-driven flow when the frequency is large enough.

Nutrigenetic screening strains of the mulberry silkworm, Bombyx mori, for nutritional efficiency.

PubMed

Ramesha, Chinnaswamy; Lakshmi, Hothur; Kumari, Savarapu Sugnana; Anuradha, Chevva M; Kumar, Chitta Suresh

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW(2), RMW(3), RMW(4), RMG(3), RMG(1), RMG(4), RMG(5), RMG(6) and APM(1) as the control. The 1(st) day of 5(th) stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering 3 different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were found; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or 'biomarkers', three polyvoltine silkworm strains (RMG(4), RMW(2), and RMW(3)) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their effective commercial utilization in the sericulture industry.

Nutrigenetic screening strains of the mulberry silkworm, Bombyx mori, for nutritional efficiency.

PubMed

Chinnaswamy, Ramesha; Lakshmi, Hothur; Kumari, Savarapu S; Anuradha, Chebba M; Kumar, Chitta S

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW(2), RMW(3), RMW(4), RMG(3), RMG(1), RMG(4), RMG(5), RMG(6) and APM(1) as the control. The 1(st) day of 5(th) stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering three different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were shown; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or 'biomarkers', three polyvoltine silkworm strains (RMG(4), RMW(2), and RMW(3)) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their effective commercial utilization in the sericulture industry.

Nutrigenetic Screening Strains of the Mulberry Silkworm, Bombyx mori, for Nutritional Efficiency

PubMed Central

Chinnaswamy, Ramesha; Lakshmi, Hothur; Kumari, Savarapu S.; Anuradha, Chebba M.; Kumar, Chitta S.

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW2, RMW3, RMW4, RMG3, RMG1, RMG4, RMG5, RMG6 and APM1 as the control. The 1st day of 5th stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering three different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were shown; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or ‘biomarkers’, three polyvoltine silkworm strains (RMG4, RMW2, and RMW3) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their effective commercial utilization in the sericulture industry. PMID:22938037

Nutrigenetic Screening Strains of the Mulberry Silkworm, Bombyx mori, for Nutritional Efficiency

PubMed Central

Ramesha, Chinnaswamy; Lakshmi, Hothur; Kumari, Savarapu Sugnana; Anuradha, Chevva M.; Kumar, Chitta Suresh

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW2, RMW3, RMW4, RMG3, RMG1, RMG4, RMG5, RMG6 and APM1 as the control. The 1st day of 5th stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering 3 different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were found; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or ‘biomarkers’, three polyvoltine silkworm strains (RMG4, RMW2, and RMW3) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their effective commercial utilization in the sericulture industry. PMID:22934597

Utility of combinations of biomarkers, cognitive markers, and risk factors to predict conversion from mild cognitive impairment to Alzheimer disease in patients in the Alzheimer's disease neuroimaging initiative.

PubMed

Gomar, Jesus J; Bobes-Bascaran, Maria T; Conejero-Goldberg, Concepcion; Davies, Peter; Goldberg, Terry E

2011-09-01

Biomarkers have become increasingly important in understanding neurodegenerative processes associated with Alzheimer disease. Markers include regional brain volumes, cerebrospinal fluid measures of pathological Aβ1-42 and total tau, cognitive measures, and individual risk factors. To determine the discriminative utility of different classes of biomarkers and cognitive markers by examining their ability to predict a change in diagnostic status from mild cognitive impairment to Alzheimer disease. Longitudinal study. We analyzed the Alzheimer's Disease Neuroimaging Initiative database to study patients with mild cognitive impairment who converted to Alzheimer disease (n = 116) and those who did not convert (n = 204) within a 2-year period. We determined the predictive utility of 25 variables from all classes of markers, biomarkers, and risk factors in a series of logistic regression models and effect size analyses. The Alzheimer's Disease Neuroimaging Initiative public database. Primary outcome measures were odds ratios, pseudo- R(2)s, and effect sizes. In comprehensive stepwise logistic regression models that thus included variables from all classes of markers, the following baseline variables predicted conversion within a 2-year period: 2 measures of delayed verbal memory and middle temporal lobe cortical thickness. In an effect size analysis that examined rates of decline, change scores for biomarkers were modest for 2 years, but a change in an everyday functional activities measure (Functional Assessment Questionnaire) was considerably larger. Decline in scores on the Functional Assessment Questionnaire and Trail Making Test, part B, accounted for approximately 50% of the predictive variance in conversion from mild cognitive impairment to Alzheimer disease. Cognitive markers at baseline were more robust predictors of conversion than most biomarkers. Longitudinal analyses suggested that conversion appeared to be driven less by changes in the neurobiologic trajectory of the disease than by a sharp decline in functional ability and, to a lesser extent, by declines in executive function.

The rectenna design on contact lens for wireless powering of the active intraocular pressure monitoring system.

PubMed

Cheng, H W; Jeng, B M; Chen, C Y; Huang, H Y; Chiou, J C; Luo, C H

2013-01-01

This paper proposed a wireless power harvesting system with micro-electro-mechanical-systems (MEMS) fabrication for noninvasive intraocular pressure (IOP) measurement on soft contact lens substructure. The power harvesting IC consists of a loop antenna, an impedance matching network and a rectifier. The proposed IC has been designed and fabricated by CMOS 0.18 um process that operates at the ISM band of 5.8 GHz. The antenna and the power harvesting IC would be bonded together by using flip chip bonding technologies without extra wire interference. The circuit utilized an impedance transformation circuit to boost the input RF signal that improves the circuit performance. The proposed design achieves an RF-to-DC conversion efficiency of 35% at 5.8 GHz.

Progress in passive solar energy systems. Volume 8. Part 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayes, J.; Andrejko, D.A.

1983-01-01

This book presents the papers given at a conference sponsored by the US DOE, the Solar Energy Research Institute, SolarVision, Inc., and the Southern California Solar Energy Society. The topics considered at the conference included sizing solar energy systems for agricultural applications, a farm scale ethanol production plant, the EEC wind energy RandD program, the passive solar performance assessment of an earth-sheltered house, the ARCO 1 MW photovoltaic power plant, the performance of a dendritic web photovoltaic module, second generation point focused concentrators, linear fresnel lens concentrating photovoltaic collectors, photovoltaic conversion efficiency, amorphous silicon thin film solar cells, a photovoltaicmore » system for a shopping center, photovoltaic power generation for the utility industry, spectral solar radiation, and the analysis of insolation data.« less

Magnetic-field-free thermoelectronic power conversion based on graphene and related two-dimensional materials

NASA Astrophysics Data System (ADS)

Wanke, R.; Hassink, G. W. J.; Stephanos, C.; Rastegar, I.; Braun, W.; Mannhart, J.

2016-06-01

Mobile energy converters require, in addition to high conversion efficiency and low cost, a low mass. We propose to utilize thermoelectronic converters that use 2D-materials such as graphene for their gate electrodes. Deriving the ultimate limit for their specific energy output, we show that the positive energy output is likely close to the fundamental limit for any conversion of heat into electric power. These converters may be valuable as electric power sources of spacecraft, and with the addition of vacuum enclosures, for power generation in electric planes and cars.

Microwave-assisted solid phase conversion study of Meldrum's acid to ethylenetetracarboxylic dianhydride (C 6O 6)

NASA Astrophysics Data System (ADS)

Taherpour, Avat (Arman)

2010-01-01

Utilization of microwave irradiation provides an effective method for fast synthesizing of some important compounds. Microwave-assisted solid phase is an especial class in chemical synthesis. By the use of MW-irradiation on chemicals, sometimes interesting results can be seen. The synthesis of the interesting molecule ethylenetetracarboxylic dianhydride (C 6O 6) was attempted with a few different methods. In this study, the microwave-assisted solid phase conversion of Meldrum's acid to ethylenetetracarboxylic dianhydride was reported. This conversion was characterized by FT-IR, GC/MS and NMR spectroscopy results.

Streak camera imaging of single photons at telecom wavelength

NASA Astrophysics Data System (ADS)

Allgaier, Markus; Ansari, Vahid; Eigner, Christof; Quiring, Viktor; Ricken, Raimund; Donohue, John Matthew; Czerniuk, Thomas; Aßmann, Marc; Bayer, Manfred; Brecht, Benjamin; Silberhorn, Christine

2018-01-01

Streak cameras are powerful tools for temporal characterization of ultrafast light pulses, even at the single-photon level. However, the low signal-to-noise ratio in the infrared range prevents measurements on weak light sources in the telecom regime. We present an approach to circumvent this problem, utilizing an up-conversion process in periodically poled waveguides in Lithium Niobate. We convert single photons from a parametric down-conversion source in order to reach the point of maximum detection efficiency of commercially available streak cameras. We explore phase-matching configurations to apply the up-conversion scheme in real-world applications.

Economic considerations in coverting from oil/gas firing to coal

NASA Technical Reports Server (NTRS)

Rau, J. G.

1978-01-01

Economic considerations involved in fuel conversion such as from oil and/or gas firing to coal are discussed including investments costs for new facilities and equipment (including air pollution control equipment), operation and maintenance costs, and purchased fuel costs. An analytical approach to assessing the cost effectiveness of fuel conversion in terms of the annual net cost of conversion, the equivalent annual number of barrels of oil saved, and the integral rate of return of the conversion investment is presented. Illustrative numerical examples are presented for typical utility boilers and industrial boiler facilities. A further consideration addressed deals with the impacts of these costs on the overall financial structure of the firm and the ability of the firm to raise the necessary investment captial.

SolarSoft Web Services

NASA Astrophysics Data System (ADS)

Freeland, S.; Hurlburt, N.

2005-12-01

The SolarSoft system (SSW) is a set of integrated software libraries, databases, and system utilities which provide a common programming and data analysis environment for solar physics. The system includes contributions from a large community base, representing the efforts of many NASA PI team MO&DA teams,spanning many years and multiple NASA and international orbital and ground based missions. The SSW general use libraries include Many hundreds of utilities which are instrument and mission independent. A large subset are also SOLAR independent, such as time conversions, digital detector cleanup, time series analysis, mathematics, image display, WWW server communications and the like. PI teams may draw on these general purpose libraries for analysis and application development while concentrating efforts on instrument specific calibration issues rather than reinvention of general use software. By the same token, PI teams are encouraged to contribute new applications or enhancements to existing utilities which may have more general interest. Recent areas of intense evolution include space weather applications, automated distributed data access and analysis, interfaces with the ongoing Virtual Solar Observatory efforts, and externalization of SolarSoft power through Web Services. We will discuss the current status of SSW web services and demonstrate how this facilitates accessing the underlying power of SolarSoft in more abstract terms. In this context, we will describe the use of SSW services within the Collaborative Sun Earth Connector environment.

Technologies for Upgrading Light Water Reactor Outlet Temperature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daniel S. Wendt; Piyush Sabharwall; Vivek Utgikar

Nuclear energy could potentially be utilized in hybrid energy systems to produce synthetic fuels and feedstocks from indigenous carbon sources such as coal and biomass. First generation nuclear hybrid energy system (NHES) technology will most likely be based on conventional light water reactors (LWRs). However, these LWRs provide thermal energy at temperatures of approximately 300°C, while the desired temperatures for many chemical processes are much higher. In order to realize the benefits of nuclear hybrid energy systems with the current LWR reactor fleets, selection and development of a complimentary temperature upgrading technology is necessary. This paper provides an initial assessmentmore » of technologies that may be well suited toward LWR outlet temperature upgrading for powering elevated temperature industrial and chemical processes during periods of off-peak power demand. Chemical heat transformers (CHTs) are a technology with the potential to meet LWR temperature upgrading requirements for NHESs. CHTs utilize chemical heat of reaction to change the temperature at which selected heat sources supply or consume thermal energy. CHTs could directly utilize LWR heat output without intermediate mechanical or electrical power conversion operations and the associated thermodynamic losses. CHT thermal characteristics are determined by selection of the chemical working pair and operating conditions. This paper discusses the chemical working pairs applicable to LWR outlet temperature upgrading and the CHT operating conditions required for providing process heat in NHES applications.« less

Summary of aerospace and nuclear engineering activities

NASA Technical Reports Server (NTRS)

1988-01-01

The Texas A&M Nuclear and Aerospace engineering departments have worked on five different projects for the NASA/USRA Advanced Design Program during the 1987/88 year. The aerospace department worked on two types of lunar tunnelers that would create habitable space. The first design used a heated cone to melt the lunar regolith, and the second used a conventional drill to bore its way through the crust. Both used a dump truck to get rid of waste heat from the reactor as well as excess regolith from the tunneling operation. The nuclear engineering department worked on three separate projects. The NEPTUNE system is a manned, outer-planetary explorer designed with Jupiter exploration as the baseline mission. The lifetime requirement for both reactor and power-conversion systems was twenty years. The second project undertaken for the power supply was a Mars Sample Return Mission power supply. This was designed to produce 2 kW of electrical power for seven years. The design consisted of a General Purpose Heat Source (GPHS) utilizing a Stirling engine as the power conversion unit. A mass optimization was performed to aid in overall design. The last design was a reactor to provide power for propulsion to Mars and power on the surface. The requirements of 300 kW of electrical power output and a mass of less than 10,000 Rg were set. This allowed the reactor and power conversion unit to fit within the Space Shuttle cargo bay.

Multi-Scale Microstructural Thermoelectric Materials: Transport Behavior, Non-Equilibrium Preparation, and Applications.

PubMed

Su, Xianli; Wei, Ping; Li, Han; Liu, Wei; Yan, Yonggao; Li, Peng; Su, Chuqi; Xie, Changjun; Zhao, Wenyu; Zhai, Pengcheng; Zhang, Qingjie; Tang, Xinfeng; Uher, Ctirad

2017-05-01

Considering only about one third of the world's energy consumption is effectively utilized for functional uses, and the remaining is dissipated as waste heat, thermoelectric (TE) materials, which offer a direct and clean thermal-to-electric conversion pathway, have generated a tremendous worldwide interest. The last two decades have witnessed a remarkable development in TE materials. This Review summarizes the efforts devoted to the study of non-equilibrium synthesis of TE materials with multi-scale structures, their transport behavior, and areas of applications. Studies that work towards the ultimate goal of developing highly efficient TE materials possessing multi-scale architectures are highlighted, encompassing the optimization of TE performance via engineering the structures with different dimensional aspects spanning from the atomic and molecular scales, to nanometer sizes, and to the mesoscale. In consideration of the practical applications of high-performance TE materials, the non-equilibrium approaches offer a fast and controllable fabrication of multi-scale microstructures, and their scale up to industrial-size manufacturing is emphasized here. Finally, the design of two integrated power generating TE systems are described-a solar thermoelectric-photovoltaic hybrid system and a vehicle waste heat harvesting system-that represent perhaps the most important applications of thermoelectricity in the energy conversion area. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

CFD analysis of municipal solid waste combustion using detailed chemical kinetic modelling.

PubMed

Frank, Alex; Castaldi, Marco J

2014-08-01

Nitrogen oxides (NO x ) emissions from the combustion of municipal solid waste (MSW) in waste-to-energy (WtE) facilities are receiving renewed attention to reduce their output further. While NO x emissions are currently 60% below allowed limits, further reductions will decrease the air pollution control (APC) system burden and reduce consumption of NH3. This work combines the incorporation of the GRI 3.0 mechanism as a detailed chemical kinetic model (DCKM) into a custom three-dimensional (3D) computational fluid dynamics (CFD) model fully to understand the NO x chemistry in the above-bed burnout zones. Specifically, thermal, prompt and fuel NO formation mechanisms were evaluated for the system and a parametric study was utilized to determine the effect of varying fuel nitrogen conversion intermediates between HCN, NH3 and NO directly. Simulation results indicate that the fuel nitrogen mechanism accounts for 92% of the total NO produced in the system with thermal and prompt mechanisms accounting for the remaining 8%. Results also show a 5% variation in final NO concentration between HCN and NH3 inlet conditions, demonstrating that the fuel nitrogen intermediate assumed is not significant. Furthermore, the conversion ratio of fuel nitrogen to NO was 0.33, revealing that the majority of fuel nitrogen forms N2. © The Author(s) 2014.

Education System Benefits of U.S. Metric Conversion.

ERIC Educational Resources Information Center

Phelps, Richard P.

1996-01-01

U.S. metric conversion efforts are reviewed as they have affected education. Education system benefits and costs are estimated for three possible system conversion plans. The soft-conversion-to-metric plan, which drops all inch-pound instruction, appears to provide the largest net benefits. The primary benefit is in class time saved. (SLD)

5 CFR 534.406 - Conversion to the SES pay system.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Conversion to the SES pay system. 534.406... UNDER OTHER SYSTEMS Pay and Performance Awards Under the Senior Executive Service § 534.406 Conversion... senior executive's converted rate of basic pay. Conversion to a new SES rate of basic pay is not...

IECEC '84: Advanced energy systems - Their role in our future; Proceedings of the Nineteenth Intersociety Energy Conversion Engineering Conference, San Francisco, CA, August 19-24, 1984. Volumes 1, 2, 3, & 4

NASA Astrophysics Data System (ADS)

Among the topics discussed are: advanced energy conversion concepts, power sources for aircraft and spacecraft, alternate fuels for industrial and vehicular applications, biomass-derived fuels, electric vehicle design and development status, electrochemical energy conversion systems, electric power generation cycles, energy-efficient industrial processes, and energy policy and system analysis. Also discussed are advanced methods for energy storage and transport, fossil fuel conversion systems, geothermal energy system development and performance, novel and advanced heat engines, hydrogen fuel-based energy systems, MHD technology development status, nuclear energy systems, solar energy conversion methods, advanced heating and cooling systems, Stirling cycle device development, terrestrial photovoltaic systems, and thermoelectric and thermionic systems.

Economic competitiveness of III-V on silicon tandem one-sun photovoltaic solar modules in favorable future scenarios

DOE PAGES

Bobela, David C.; Gedvilas, Lynn; Woodhouse, Michael; ...

2016-09-05

Here, tandem modules combining a III-V top cell with a Si bottom cell offer the potential to increase the solar energy conversion efficiency of one-sun photovoltaic modules beyond 25%, while fully utilizing the global investment that has been made in Si photovoltaics manufacturing. At present, the cost of III-V cells is far too high for this approach to be competitive for one-sun terrestrial power applications. We investigated the system-level economic benefits of both GaAs/Si and InGaP/Si tandem modules in favorable future scenarios where the cost of III-V cells is substantially reduced, perhaps to less than the cost of Si cells.more » We found, somewhat unexpectedly, that these tandems can reduce installed system cost only when the area-related balance-of-system cost is high, such as for area-constrained residential rooftop systems in the USA. When area-related balance-of-system cost is lower, such as for utility-scale systems, the tandem module offers no benefit. This is because a system using tandem modules is more expensive than one using single-junction Si modules when III-V cells are expensive, and a system using tandem modules is more expensive than one using single-junction III-V modules when III-V cells are inexpensive.« less

Economic competitiveness of III-V on silicon tandem one-sun photovoltaic solar modules in favorable future scenarios

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bobela, David C.; Gedvilas, Lynn; Woodhouse, Michael

Here, tandem modules combining a III-V top cell with a Si bottom cell offer the potential to increase the solar energy conversion efficiency of one-sun photovoltaic modules beyond 25%, while fully utilizing the global investment that has been made in Si photovoltaics manufacturing. At present, the cost of III-V cells is far too high for this approach to be competitive for one-sun terrestrial power applications. We investigated the system-level economic benefits of both GaAs/Si and InGaP/Si tandem modules in favorable future scenarios where the cost of III-V cells is substantially reduced, perhaps to less than the cost of Si cells.more » We found, somewhat unexpectedly, that these tandems can reduce installed system cost only when the area-related balance-of-system cost is high, such as for area-constrained residential rooftop systems in the USA. When area-related balance-of-system cost is lower, such as for utility-scale systems, the tandem module offers no benefit. This is because a system using tandem modules is more expensive than one using single-junction Si modules when III-V cells are expensive, and a system using tandem modules is more expensive than one using single-junction III-V modules when III-V cells are inexpensive.« less

Analysis of integrated photovoltaic-thermal systems using solar concentrators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yusoff, M.B.

1983-01-01

An integrated photovoltaic-thermal system using solar concentrators utilizes the solar radiation spectrum in the production of electrical and thermal energy. The electrical conversion efficiency of this system decreases with increasing solar cell temperature. Since a high operating temperature is desirable to maximize the quality of thermal output of the planned integrated system, a proper choice of the operating temperature for the unit cell is of vital importance. The analysis predicts performance characteristics of the unit cell by considering the dependence of the heat generation, the heat absorption and the heat transmission on the material properties of the unit cell structure.more » An analytical model has been developed to describe the heat transport phenomena occurring in the unit cell structure. The range of applicability of the one-dimensional and the two-dimensional models, which have closed-form solutions, has been demonstrated. Parametric and design studies point out the requirements for necessary good electrical and thermal performance. A procedure utilizing functional forms of component characteristics in the form of partial coefficients of the dependent variable has been developed to design and operate the integrated system to have a desirable value of the thermal to electrical output ratio both at design and operating modes.« less

Performance and economic risk evaluation of dispersed solar thermal power systems by Monte Carlo simulation

NASA Technical Reports Server (NTRS)

Manvi, R.; Fujita, T.

1978-01-01

A preliminary comparative evaluation of dispersed solar thermal power plants utilizing advanced technologies available in 1985-2000 time frame is under way at JPL. The solar power plants of 50 KWe to 10 MWe size are equipped with two axis tracking parabolic dish concentrator systems operating at temperatures in excess of 1000 F. The energy conversion schemes under consideration include advanced steam, open and closed cycle gas turbines, stirling, and combined cycle. The energy storage systems include advanced batteries, liquid metal, and chemical. This paper outlines a simple methodology for a probabilistic assessment of such systems. Sources of uncertainty in the development of advanced systems are identified, and a computer Monte Carlo simulation is exercised to permit an analysis of the tradeoffs of the risk of failure versus the potential for large gains. Frequency distribution of energy cost for several alternatives are presented.

Molten salt parabolic trough system with synthetic oil preheating

NASA Astrophysics Data System (ADS)

Yuasa, Minoru; Hino, Koichi

2017-06-01

Molten salt parabolic trough system (MSPT), which can heat the heat transfer fluid (HTF) to 550 °C has a better performance than a synthetic oil parabolic trough system (SOPT), which can heat the HTF to 400 °C or less. The utilization of HTF at higher temperature in the parabolic trough system is able to realize the design of a smaller size of storage tank and higher heat to electricity conversion efficiency. However, with MSPT there is a great amount of heat loss at night so it is necessary to circulate the HTF at a high temperature of about 290 °C in order to prevent solidification. A new MSPT concept with SOPT preheating (MSSOPT) has been developed to reduce the heat loss at night. In this paper, the MSSOPT system, its performance by steady state analysis and annual performance analysis are introduced.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The objective of the contract is to consolidate the advances made during the previous contract in the conversion of syngas to motor fuels using Molecular Sieve-containing catalysts and to demonstrate the practical utility and economic value of the new catalyst/process systems with appropriate laboratory runs. Work on the program is divided into the following six tasks: (1) preparation of a detailed work plan covering the entire performance of the contract; (2) preliminary techno-economic assessment of the UCC catalyst/process system; (3) optimization of the most promising catalysts developed under prior contract; (4) optimization of the UCC catalyst system in a mannermore » that will give it the longest possible service life; (5) optimization of a UCC process/catalyst system based upon a tubular reactor with a recycle loop; and (6) economic evaluation of the optimal performance found under Task 5 for the UCC process/catalyst system. Accomplishments are reported for Tasks 2 through 5.« less

Membrane technology revolutionizes water treatment.

PubMed

Wilderer, P A; Paris, S

2007-01-01

Membranes play a crucial role in living cells, plants and animals. They not only serve as barriers between the inside and outside world of cells and organs. More importantly, they are means of selective transport of materials and host for biochemical conversion. Natural membrane systems have demonstrated efficiency and reliability for millions of years and it is remarkable that most of these systems are small, efficient and highly reliable even under rapidly changing ambient conditions. Thus, it appears to be advisable for technology developers to keep a close eye on Mother Nature. By doing so it is most likely that ideas for novel technical solutions are born. Following the concept of natural systems it is hypothesized that the Millennium Development Goals can be best met when counting on small water and wastewater treatment systems. The core of such systems could be membranes in which chemical reactions are integrated allowing recovery and direct utilization of valuable substances.

Integration of CdSe/CdSexTe1−x Type-II Heterojunction Nanorods into Hierarchically Porous TiO2 Electrode for Efficient Solar Energy Conversion

PubMed Central

Lee, Sangheon; Flanagan, Joseph C.; Kang, Joonhyeon; Kim, Jinhyun; Shim, Moonsub; Park, Byungwoo

2015-01-01

Semiconductor sensitized solar cells, a promising candidate for next-generation photovoltaics, have seen notable progress using 0-D quantum dots as light harvesting materials. Integration of higher-dimensional nanostructures and their multi-composition variants into sensitized solar cells is, however, still not fully investigated despite their unique features potentially beneficial for improving performance. Herein, CdSe/CdSexTe1−x type-II heterojunction nanorods are utilized as novel light harvesters for sensitized solar cells for the first time. The CdSe/CdSexTe1−x heterojunction-nanorod sensitized solar cell exhibits ~33% improvement in the power conversion efficiency compared to its single-component counterpart, resulting from superior optoelectronic properties of the type-II heterostructure and 1-octanethiol ligands aiding facile electron extraction at the heterojunction nanorod-TiO2 interface. Additional ~32% enhancement in power conversion efficiency is achieved by introducing percolation channels of large pores in the mesoporous TiO2 electrode, which allow 1-D sensitizers to infiltrate the entire depth of electrode. These strategies combined together lead to 3.02% power conversion efficiency, which is one of the highest values among sensitized solar cells utilizing 1-D nanostructures as sensitizer materials. PMID:26638994

Food waste-to-energy conversion technologies: current status and future directions.

PubMed

Pham, Thi Phuong Thuy; Kaushik, Rajni; Parshetti, Ganesh K; Mahmood, Russell; Balasubramanian, Rajasekhar

2015-04-01

Food waste represents a significantly fraction of municipal solid waste. Proper management and recycling of huge volumes of food waste are required to reduce its environmental burdens and to minimize risks to human health. Food waste is indeed an untapped resource with great potential for energy production. Utilization of food waste for energy conversion currently represents a challenge due to various reasons. These include its inherent heterogeneously variable compositions, high moisture contents and low calorific value, which constitute an impediment for the development of robust, large scale, and efficient industrial processes. Although a considerable amount of research has been carried out on the conversion of food waste to renewable energy, there is a lack of comprehensive and systematic reviews of the published literature. The present review synthesizes the current knowledge available in the use of technologies for food-waste-to-energy conversion involving biological (e.g. anaerobic digestion and fermentation), thermal and thermochemical technologies (e.g. incineration, pyrolysis, gasification and hydrothermal oxidation). The competitive advantages of these technologies as well as the challenges associated with them are discussed. In addition, the future directions for more effective utilization of food waste for renewable energy generation are suggested from an interdisciplinary perspective. Copyright © 2014 Elsevier Ltd. All rights reserved.

Utilization of biomass in the U.S. for the production of ethanol fuel as a gasoline replacement. I - Terrestrial resource potential. II - Energy requirements, with emphasis on lignocellulosic conversion

NASA Astrophysics Data System (ADS)

Ferchak, J. D.; Pye, E. K.

The paper assesses the biomass resource represented by starch derived from feed corn, surplus and distressed grain, and high-yield sugar crops planted on set-aside land in the U.S. It is determined that the quantity of ethanol produced may be sufficient to replace between 5 to 27% of present gasoline requirements. Utilization of novel cellulose conversion technology may in addition provide fermentable sugars from municipal, agricultural and forest wastes, and ultimately from highly productive silvicultural operations. The potential additional yield of ethanol from lignocellulosic biomass appears to be well in excess of liquid fuel requirements of an enhanced-efficiency transport sector at present mileage demands. No conflict with food production would be entailed. A net-energy assessment is made for lignocellulosic biomass feedstocks' conversion to ethanol and an almost 10:1 energy yield/energy cost ratio determined. It is also found that novel cellulose pretreatment and enzymatic conversion methods still under development may significantly improve even that figure, and that both chemical-feedstocks and energy-yielding byproducts such as carbon dioxide, biogas and lignin make ethanol production potentially energy self-sufficient. A final high-efficiency production approach incorporates site-optimized, nonpolluting energy sources such as solar and geothermal.

Integration of CdSe/CdSexTe1-x Type-II Heterojunction Nanorods into Hierarchically Porous TiO2 Electrode for Efficient Solar Energy Conversion.

PubMed

Lee, Sangheon; Flanagan, Joseph C; Kang, Joonhyeon; Kim, Jinhyun; Shim, Moonsub; Park, Byungwoo

2015-12-07

Semiconductor sensitized solar cells, a promising candidate for next-generation photovoltaics, have seen notable progress using 0-D quantum dots as light harvesting materials. Integration of higher-dimensional nanostructures and their multi-composition variants into sensitized solar cells is, however, still not fully investigated despite their unique features potentially beneficial for improving performance. Herein, CdSe/CdSe(x)Te(1-x) type-II heterojunction nanorods are utilized as novel light harvesters for sensitized solar cells for the first time. The CdSe/CdSe(x)Te(1-x) heterojunction-nanorod sensitized solar cell exhibits ~33% improvement in the power conversion efficiency compared to its single-component counterpart, resulting from superior optoelectronic properties of the type-II heterostructure and 1-octanethiol ligands aiding facile electron extraction at the heterojunction nanorod-TiO(2) interface. Additional ~31% enhancement in power conversion efficiency is achieved by introducing percolation channels of large pores in the mesoporous TiO(2) electrode, which allow 1-D sensitizers to infiltrate the entire depth of electrode. These strategies combined together lead to 3.02% power conversion efficiency, which is one of the highest values among sensitized solar cells utilizing 1-D nanostructures as sensitizer materials.

Energy efficiency evaluation of a stationary lithium-ion battery container storage system via electro-thermal modeling and detailed component analysis

DOE PAGES

Schimpe, Michael; Naumann, Maik; Truong, Nam; ...

2017-11-08

Energy efficiency is a key performance indicator for battery storage systems. A detailed electro-thermal model of a stationary lithium-ion battery system is developed and an evaluation of its energy efficiency is conducted. The model offers a holistic approach to calculating conversion losses and auxiliary power consumption. Sub-models for battery rack, power electronics, thermal management as well as the control and monitoring components are developed and coupled to a comprehensive model. The simulation is parametrized based on a prototype 192 kWh system using lithium iron phosphate batteries connected to the low voltage grid. The key loss mechanisms are identified, thoroughly analyzedmore » and modeled. Generic profiles featuring various system operation modes are evaluated to show the characteristics of stationary battery systems. Typically the losses in the power electronics outweigh the losses in the battery at low power operating points. The auxiliary power consumption dominates for low system utilization rates. For estimation of real-world performance, the grid applications Primary Control Reserve, Secondary Control Reserve and the storage of surplus photovoltaic power are evaluated. Conversion round-trip efficiency is in the range of 70-80%. Finally, overall system efficiency, which also considers system power consumption, is 8-13 percentage points lower for Primary Control Reserve and the photovoltaic-battery application. However, for Secondary Control Reserve, the total round-trip efficiency is found to be extremely low at 23% due to the low energy throughput of this application type.« less

Energy efficiency evaluation of a stationary lithium-ion battery container storage system via electro-thermal modeling and detailed component analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schimpe, Michael; Naumann, Maik; Truong, Nam

Energy efficiency is a key performance indicator for battery storage systems. A detailed electro-thermal model of a stationary lithium-ion battery system is developed and an evaluation of its energy efficiency is conducted. The model offers a holistic approach to calculating conversion losses and auxiliary power consumption. Sub-models for battery rack, power electronics, thermal management as well as the control and monitoring components are developed and coupled to a comprehensive model. The simulation is parametrized based on a prototype 192 kWh system using lithium iron phosphate batteries connected to the low voltage grid. The key loss mechanisms are identified, thoroughly analyzedmore » and modeled. Generic profiles featuring various system operation modes are evaluated to show the characteristics of stationary battery systems. Typically the losses in the power electronics outweigh the losses in the battery at low power operating points. The auxiliary power consumption dominates for low system utilization rates. For estimation of real-world performance, the grid applications Primary Control Reserve, Secondary Control Reserve and the storage of surplus photovoltaic power are evaluated. Conversion round-trip efficiency is in the range of 70-80%. Finally, overall system efficiency, which also considers system power consumption, is 8-13 percentage points lower for Primary Control Reserve and the photovoltaic-battery application. However, for Secondary Control Reserve, the total round-trip efficiency is found to be extremely low at 23% due to the low energy throughput of this application type.« less

Modeling of photoluminescence in laser-based lighting systems

NASA Astrophysics Data System (ADS)

Chatzizyrli, Elisavet; Tinne, Nadine; Lachmayer, Roland; Neumann, Jörg; Kracht, Dietmar

2017-12-01

The development of laser-based lighting systems has been the latest step towards a revolution in illumination technology brought about by solid-state lighting. Laser-activated remote phosphor systems produce white light sources with significantly higher luminance than LEDs. The weak point of such systems is often considered to be the conversion element. The high-intensity exciting laser beam in combination with the limited thermal conductivity of ceramic phosphor materials leads to thermal quenching, the phenomenon in which the emission efficiency decreases as temperature rises. For this reason, the aim of the presented study is the modeling of remote phosphor systems in order to investigate their thermal limitations and to calculate the parameters for optimizing the efficiency of such systems. The common approach to simulate remote phosphor systems utilizes a combination of different tools such as ray tracing algorithms and wave optics tools for describing the incident and converted light, whereas the modeling of the conversion process itself, i.e. photoluminescence, in most cases is circumvented by using the absorption and emission spectra of the phosphor material. In this study, we describe the processes involved in luminescence quantum-mechanically using the single-configurational-coordinate diagram as well as the Franck-Condon principle and propose a simulation model that incorporates the temperature dependence of these processes. Following an increasing awareness of climate change and environmental issues, the development of ecologically friendly lighting systems featuring low power consumption and high luminous efficiency is imperative more than ever. The better understanding of laser-based lighting systems is an important step towards that aim as they may improve on LEDs in the near future.

FOCUSing on Innovative Solar Technologies

ScienceCinema

Rohlfing, Eric; Holman, Zak, Angel, Roger

2018-06-22

Many of ARPA-E’s technology programs seek to break down silos and build new technological communities around a specific energy challenge. In this video, ARPA-E’s Deputy Director for Technology Eric Rohlfing, discusses how the Full-Spectrum Optimized Conversion and Utilization of Sunlight (FOCUS) program is bringing together the photovoltaic (PV) and concentrated solar power (CSP) communities to develop hybrid solar energy systems. This video features interviews with innovators from the FOCUS project team made up by Arizona State University and the University of Arizona, and showcases how the FOCUS program is combining.

Palladium-catalyzed Kumada coupling reaction of bromoporphyrins with silylmethyl Grignard reagents: preparation of silylmethyl-substituted porphyrins as a multipurpose synthon for fabrication of porphyrin systems.

PubMed

Sugita, Noriaki; Hayashi, Satoshi; Hino, Fumio; Takanami, Toshikatsu

2012-12-07

We have developed an efficient method for preparing silylmethyl-substituted porphyrins via the palladium-catalyzed Kumada cross-coupling reaction of bromoporphyrins with silylmethyl Grignard reagents. We demonstrated the synthetic utility of these silylmethylporphyrins as a multipurpose synthon for fabricating porphyrin derivatives through a variety of transformations of the silylmethyl groups, including the DDQ-promoted oxidative conversion to CHO, CH(2)OH, CH(2)OMe, and CH(2)F functionalities and the fluoride ion-mediated desilylative introduction of carbon-carbon single and double bonds.

A Brayton cycle solar dynamic heat receiver for space

NASA Technical Reports Server (NTRS)

Sedgwick, L. M.; Nordwall, H. L.; Kaufmann, K. J.; Johnson, S. D.

1989-01-01

The detailed design of a heat receiver developed to meet the requirements of the Space Station Freedom, which will be assembled and operated in low earth orbit beginning in the mid-1990's, is described. The heat receiver supplies thermal energy to a nominal 25-kW closed-Brayton-cycle power conversion unit. The receiver employs an integral thermal energy storage system utilizing the latent heat of a eutectic-salt phase-change mixture to store energy for eclipse operation. The salt is contained within a felt metal matrix which enhances heat transfer and controls the salt void distribution during solidification.

Ruthenium-Catalyzed Synthesis of Dialkoxymethane Ethers Utilizing Carbon Dioxide and Molecular Hydrogen.

PubMed

Thenert, Katharina; Beydoun, Kassem; Wiesenthal, Jan; Leitner, Walter; Klankermayer, Jürgen

2016-09-26

The synthesis of dimethoxymethane (DMM) by a multistep reaction of methanol with carbon dioxide and molecular hydrogen is reported. Using the molecular catalyst [Ru(triphos)(tmm)] in combination with the Lewis acid Al(OTf)3 resulted in a versatile catalytic system for the synthesis of various dialkoxymethane ethers. This new catalytic reaction provides the first synthetic example for the selective conversion of carbon dioxide and hydrogen into a formaldehyde oxidation level, thus opening access to new molecular structures using this important C1 source. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.