Science.gov

Sample records for electricity savings potentials

  1. Electrical energy and cost savings potential at DOD facilities

    SciTech Connect

    Konopacki, S.; Akbari, H.; Lister, L.; DeBaille, L.

    1996-06-01

    The US Department of Defense (DOD) has been mandated to reduce energy consumption and costs by 20% from 1985 to 2000 and by 30% from 1985 to 2005. Reduction of electrical energy consumption at DOD facilities requires a better understanding of energy consumption patterns and energy and financial savings potential. This paper utilizes two independent studies--EDA (End-Use Disaggregation Algorithm) and MEIP (Model Energy Installation Program)--and whole-installation electricity use data obtained from a state utility to estimate electrical energy conservation potential (ECP) and cost savings potential (CSP) at the Fort Hood, Texas, military installation and at DOD nationwide. At Fort Hood, the authors estimated an annual electricity savings of 62.2 GWh/yr (18%), a peak demand savings of 10.1 MW (14%), and an annual energy cost savings of $6.5 million per year. These savings could be attained with an initial investment of $41.1 million, resulting in a simple payback of 6.3 years. Across the DOD, they estimated an annual electricity savings of 4,900 GWh/yr, a peak demand savings of 694 MW, and an annual energy cost savings of $316 million per year. The estimated cost savings is 16% of the total nationwide DOD 1993 annual energy costs. These savings could be attained with an initial investment of $1.23 billion, resulting in a simple payback of 3.9 years.

  2. Furnace Blower Electricity: National and Regional Savings Potential

    SciTech Connect

    Florida Solar Energy Center; Franco, Victor; Franco, Victor; Lutz, Jim; Lekov, Alex; Gu, Lixing

    2008-05-16

    Currently, total electricity consumption of furnaces is unregulated, tested at laboratory conditions using the DOE test procedure, and is reported in the GAMA directory as varying from 76 kWh/year to 1,953 kWh/year. Furnace blowers account for about 80percent of the total furnace electricity consumption and are primarily used to distribute warm air throughout the home during furnace operation as well as distribute cold air during air conditioning operation. Yet the furnace test procedure does not provide a means to calculate the electricity consumption during cooling operation or standby, which account for a large fraction of the total electricity consumption. Furthermore, blower electricity consumption is strongly affected by static pressure. Field data shows that static pressure in the house distribution ducts varies widely and that the static pressure used in the test procedure as well as the calculated fan power is not representative of actual field installations. Therefore, accurate determination of the blower electricity consumption is important to address electricity consumption of furnaces and air conditioners. This paper compares the potential regional and national energy savings of two-stage brushless permanent magnet (BPM) blower motors (the blower design option with the most potential savings that is currently available in the market) to single-stage permanent split capacitor (PSC) blower motors (the most common blower design option). Computer models were used to generate the heating and cooling loads for typical homes in 16 different climates which represent houses throughout the United States. The results show that the potential savings of using BPM motors vary by region and house characteristics, and are very strongly tied to improving house distribution ducts. Savings decrease dramatically with increased duct pressure. Cold climate locations will see savings even in the high static pressure duct situations, while warm climate locations will see less

  3. DSM Electricity Savings Potential in the Buildings Sector in APP Countries

    SciTech Connect

    McNeil, MIchael; Letschert, Virginie; Shen, Bo; Sathaye, Jayant; de la Ru du Can, Stephane

    2011-01-12

    The global economy has grown rapidly over the past decade with a commensurate growth in the demand for electricity services that has increased a country's vulnerability to energy supply disruptions. Increasing need of reliable and affordable electricity supply is a challenge which is before every Asia Pacific Partnership (APP) country. Collaboration between APP members has been extremely fruitful in identifying potential efficiency upgrades and implementing clean technology in the supply side of the power sector as well established the beginnings of collaboration. However, significantly more effort needs to be focused on demand side potential in each country. Demand side management or DSM in this case is a policy measure that promotes energy efficiency as an alternative to increasing electricity supply. It uses financial or other incentives to slow demand growth on condition that the incremental cost needed is less than the cost of increasing supply. Such DSM measures provide an alternative to building power supply capacity The type of financial incentives comprise of rebates (subsidies), tax exemptions, reduced interest loans, etc. Other approaches include the utilization of a cap and trade scheme to foster energy efficiency projects by creating a market where savings are valued. Under this scheme, greenhouse gas (GHG) emissions associated with the production of electricity are capped and electricity retailers are required to meet the target partially or entirely through energy efficiency activities. Implementation of DSM projects is very much in the early stages in several of the APP countries or localized to a regional part of the country. The purpose of this project is to review the different types of DSM programs experienced by APP countries and to estimate the overall future potential for cost-effective demand-side efficiency improvements in buildings sectors in the 7 APP countries through the year 2030. Overall, the savings potential is estimated to be 1

  4. Energy Savings Potential and Opportunities for High-Efficiency Electric Motors in Residential and Commercial Equipment

    SciTech Connect

    Goetzler, William; Sutherland, Timothy; Reis, Callie

    2013-12-04

    This report describes the current state of motor technology and estimates opportunities for energy savings through application of more advanced technologies in a variety of residential and commercial end uses. The objectives of this report were to characterize the state and type of motor technologies used in residential and commercial appliances and equipment and to identify opportunities to reduce the energy consumption of electric motor-driven systems in the residential and commercial sectors through the use of advanced motor technologies. After analyzing the technical savings potential offered by motor upgrades and variable speed technologies, recommended actions are presented.

  5. Ideas To Save Electricity

    ERIC Educational Resources Information Center

    Gardner, John C.

    1974-01-01

    Significant energy savings can be effected through stopping obvious waste of water, electricity, and heat; purchasing equipment with the correct voltage and horsepower; equipment maintenance; and redesigning or replacing obsolete or inefficient equipment. (Author/MF)

  6. Electrically switchable polymer stabilised broadband infrared reflectors and their potential as smart windows for energy saving in buildings

    PubMed Central

    Khandelwal, Hitesh; Loonen, Roel C. G. M.; Hensen, Jan L. M.; Debije, Michael G.; Schenning, Albertus P. H. J.

    2015-01-01

    Electrically switchable broadband infrared reflectors that are relatively transparent in the visible region have been fabricated using polymer stabilised cholesteric liquid crystals. The IR reflectors can change their reflection/transmission properties by applying a voltage in response to changes in environmental conditions. Simulations predict that a significant amount of energy can be saved on heating, cooling and lighting of buildings in places such as Madrid by using this switchable IR reflector. We have also fabricated a switchable IR reflector which can also generate electricity. These polymer based switchable IR reflectors are of high potential as windows of automobiles and buildings to control interior temperatures and save energy. PMID:26132328

  7. Electrically switchable polymer stabilised broadband infrared reflectors and their potential as smart windows for energy saving in buildings.

    PubMed

    Khandelwal, Hitesh; Loonen, Roel C G M; Hensen, Jan L M; Debije, Michael G; Schenning, Albertus P H J

    2015-01-01

    Electrically switchable broadband infrared reflectors that are relatively transparent in the visible region have been fabricated using polymer stabilised cholesteric liquid crystals. The IR reflectors can change their reflection/transmission properties by applying a voltage in response to changes in environmental conditions. Simulations predict that a significant amount of energy can be saved on heating, cooling and lighting of buildings in places such as Madrid by using this switchable IR reflector. We have also fabricated a switchable IR reflector which can also generate electricity. These polymer based switchable IR reflectors are of high potential as windows of automobiles and buildings to control interior temperatures and save energy. PMID:26132328

  8. Electrically switchable polymer stabilised broadband infrared reflectors and their potential as smart windows for energy saving in buildings

    NASA Astrophysics Data System (ADS)

    Khandelwal, Hitesh; Loonen, Roel C. G. M.; Hensen, Jan L. M.; Debije, Michael G.; Schenning, Albertus P. H. J.

    2015-07-01

    Electrically switchable broadband infrared reflectors that are relatively transparent in the visible region have been fabricated using polymer stabilised cholesteric liquid crystals. The IR reflectors can change their reflection/transmission properties by applying a voltage in response to changes in environmental conditions. Simulations predict that a significant amount of energy can be saved on heating, cooling and lighting of buildings in places such as Madrid by using this switchable IR reflector. We have also fabricated a switchable IR reflector which can also generate electricity. These polymer based switchable IR reflectors are of high potential as windows of automobiles and buildings to control interior temperatures and save energy.

  9. Saving Electricity and Demand Response

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Nobuyuki

    A lot of people lost their lives in the tremendous earthquake in Tohoku region on March 11. A large capacity of electric power plants in TEPCO area was also damaged and large scale power shortage in this summer is predicted. In this situation, electricity customers are making great effort to save electricity to avoid planned outage. Customers take actions not only by their selves but also by some customers' cooperative movements. All actions taken actually are based on responses to request form the government or voluntary decision. On the other hand, demand response based on a financial stimulus is not observed as an actual behavior. Saving electricity by this demand response only discussed in the newspapers. In this commentary, the events regarding electricity-saving measure after this disaster are described and the discussions on demand response, especially a raise in power rate, are put into shapes in the context of this electricity supply-demand gap.

  10. Electric energy savings from new technologies

    SciTech Connect

    Moe, R.J.; Harrer, B.J.; Kellogg, M.A.; Lyke, A.J.; Imhoff, K.L.; Fisher, Z.J.

    1986-01-01

    Purpose of the report is to provide information about the electricity-saving potential of new technologies to OCEP that it can use in developing alternative long-term projections of US electricity consumption. Low-, base-, and high-case scenarios of the electricity savings for ten technologies were prepared. The total projected annual savings for the year 2000 for all ten technologies were 137 billion kilowatt hours (BkWh), 279 BkWh, and 470 BkWh, respectively, for the three cases. The magnitude of these savings projections can be gauged by comparing them to the Department's reference case projection for the 1985 National Energy Policy Plan. In the Department's reference case, total consumption in 2000 is projected to be 3319 BkWh. Thus, the savings projected here represent between 4% and 14% of total consumption projected for 2000. Because approximately 75% of the base-case estimate of savings are already incorporated into the reference forecast, reducing projected electricity consumption from what it otherwise would have been, the savings estimated here should not be directly subtracted from the reference forecast.

  11. Electric energy savings from new technologies. Revision 1

    SciTech Connect

    Harrer, B.J.; Kellogg, M.A.; Lyke, A.J.; Imhoff, K.L.; Fisher, Z.J.

    1986-09-01

    Purpose of the report is to provide information about the electricity-saving potential of new technologies to OCEP that it can use in developing alternative long-term projections of US electricity consumption. Low-, base-, and high-case scenarios of the electricity savings for 10 technologies were prepared. The total projected annual savings for the year 2000 for all 10 technologies were 137 billion kilowatt hours (BkWh), 279 BkWh, and 470 BkWh, respectively, for the three cases. The magnitude of these savings projections can be gauged by comparing them to the Department's reference case projection for the 1985 National Energy Policy Plan. In the Department's reference case, total consumption in 2000 is projected to be 3319 BkWh. Because approximately 75% of the base-case estimate of savings are already incorporated into the reference projection, only 25% of the savings estimated here should be subtracted from the reference projection for analysis purposes.

  12. A technical analysis for cogeneration systems with potential applications in twelve California industrial plants. [energy saving heat-electricity utility systems

    NASA Technical Reports Server (NTRS)

    Moretti, V. C.; Davis, H. S.; Slonski, M. L.

    1978-01-01

    In a study sponsored by the State of California Energy Resources Conservation and Development Commission, 12 industrial plants in five utility districts were surveyed to assess the potential applications of the cogeneration of heat and electricity in California industry. Thermodynamic calculations were made for each plant in determining the energy required to meet the existing electrical and steam demands. The present systems were then compared to conceptual cogeneration systems specified for each plant. Overall energy savings were determined for the cogeneration applications. Steam and gas turbine topping cycle systems were considered as well as bottoming cycle systems. Types of industries studied were: pulp and paper, timber, cement, petroleum refining, enhanced oil recovery, foods processing, steel and glass

  13. Defining a Standard Metric for Electricity Savings

    SciTech Connect

    Brown, Marilyn; Akbari, Hashem; Blumstein, Carl; Koomey, Jonathan; Brown, Richard; Calwell, Chris; Carter, Sheryl; Cavanagh, Ralph; Chang, Audrey; Claridge, David; Craig, Paul; Diamond, Rick; Eto, Joseph H.; Fulkerson, William; Gadgil, Ashok; Geller, Howard; Goldemberg, Jose; Goldman, Chuck; Goldstein, David B.; Greenberg, Steve; Hafemeister, David; Harris, Jeff; Harvey, Hal; Heitz, Eric; Hirst, Eric; Hummel, Holmes; Kammen, Dan; Kelly, Henry; Laitner, Skip; Levine, Mark; Lovins, Amory; Masters, Gil; McMahon, James E.; Meier, Alan; Messenger, Michael; Millhone, John; Mills, Evan; Nadel, Steve; Nordman, Bruce; Price, Lynn; Romm, Joe; Ross, Marc; Rufo, Michael; Sathaye, Jayant; Schipper, Lee; Schneider, Stephen H; Sweeney, James L; Verdict, Malcolm; Vorsatz, Diana; Wang, Devra; Weinberg, Carl; Wilk, Richard; Wilson, John; Worrell, Ernst

    2009-03-01

    The growing investment by governments and electric utilities in energy efficiency programs highlights the need for simple tools to help assess and explain the size of the potential resource. One technique that is commonly used in this effort is to characterize electricity savings in terms of avoided power plants, because it is easier for people to visualize a power plant than it is to understand an abstraction such as billions of kilowatt-hours. Unfortunately, there is no standardization around the characteristics of such power plants. In this letter we define parameters for a standard avoided power plant that have physical meaning and intuitive plausibility, for use in back-of-the-envelope calculations. For the prototypical plant this article settles on a 500 MW existing coal plant operating at a 70percent capacity factor with 7percent T&D losses. Displacing such a plant for one year would save 3 billion kW h per year at the meter and reduce emissions by 3 million metric tons of CO2 per year. The proposed name for this metric is the Rosenfeld, in keeping with the tradition among scientists of naming units in honor of the person most responsible for the discovery and widespread adoption of the underlying scientific principle in question--Dr. Arthur H. Rosenfeld.

  14. Potential Water and Energy Savings from Showerheads

    SciTech Connect

    Biermayer, Peter J.

    2005-09-28

    This paper estimates the benefits and costs of six water reduction scenarios. Benefits and costs of showerhead scenarios are ranked in this paper by an estimated water reduction percentage. To prioritize potential water and energy saving scenarios regarding showerheads, six scenarios were analyzed for their potential water and energy savings and the associated dollar savings to the consumer.

  15. Investigating energy-saving potentials in the cloud.

    PubMed

    Lee, Da-Sheng

    2014-01-01

    Collecting webpage messages can serve as a sensor for investigating the energy-saving potential of buildings. Focusing on stores, a cloud sensor system is developed to collect data and determine their energy-saving potential. The owner of a store under investigation must register online, report the store address, area, and the customer ID number on the electric meter. The cloud sensor system automatically surveys the energy usage records by connecting to the power company website and calculating the energy use index (EUI) of the store. Other data includes the chain store check, company capital, location price, and the influence of weather conditions on the store; even the exposure frequency of store under investigation may impact the energy usage collected online. After collecting data from numerous stores, a multi-dimensional data array is constructed to determine energy-saving potential by identifying stores with similarity conditions. Similarity conditions refer to analyzed results that indicate that two stores have similar capital, business scale, weather conditions, and exposure frequency on web. Calculating the EUI difference or pure technical efficiency of stores, the energy-saving potential is determined. In this study, a real case study is performed. An 8-dimensional (8D) data array is constructed by surveying web data related to 67 stores. Then, this study investigated the savings potential of the 33 stores, using a site visit, and employed the cloud sensor system to determine the saving potential. The case study results show good agreement between the data obtained by the site visit and the cloud investigation, with errors within 4.17%. Among 33 the samples, eight stores have low saving potentials of less than 5%. The developed sensor on the cloud successfully identifies them as having low saving potential and avoids wasting money on the site visit. PMID:24561405

  16. Economic Energy Savings Potential in Federal Buildings

    SciTech Connect

    Brown, Daryl R.; Dirks, James A.; Hunt, Diane M.

    2000-09-04

    The primary objective of this study was to estimate the current life-cycle cost-effective (i.e., economic) energy savings potential in Federal buildings and the corresponding capital investment required to achieve these savings, with Federal financing. Estimates were developed for major categories of energy efficiency measures such as building envelope, heating system, cooling system, and lighting. The analysis was based on conditions (building stock and characteristics, retrofit technologies, interest rates, energy prices, etc.) existing in the late 1990s. The potential impact of changes to any of these factors in the future was not considered.

  17. Savings potential of ENERGY STAR (registered trademark) voluntary labeling programs

    SciTech Connect

    Webber, Carrie A.; Brown, Richard E.

    1998-06-19

    In 1993 the U.S. Environmental Protection Agency (EPA) introduced ENERGY STAR (registered trademark), a voluntary labeling program designed to identify and promote energy-efficient products. Since then EPA, now in partnership with the U.S. Department of Energy (DOE), has introduced programs for more than twenty products, spanning office equipment, residential heating and cooling equipment, new homes, commercial and residential lighting, home electronics, and major appliances. We present potential energy, dollar and carbon savings forecasts for these programs for the period 1998 to 2010. Our target market penetration case represents our best estimate of future ENERGY STAR savings. It is based on realistic market penetration goals for each of the products. We also provide results under the assumption of 100% market penetration; that is, we assume that all purchasers buy ENERGY STAR-compliant products instead of standard efficiency products throughout the analysis period. Finally, we assess the sensitivity of our target penetration case forecasts to greater or lesser marketing success by EPA and DOE, lower-than-expected future energy prices, and higher or lower rates of carbon emission by electricity generators. The potential savings of ENERGY STAR are substantial. If all purchasers chose Energy Star-compliant products instead of standard efficiency products over the next 15 years, they would save more than $100 billion on their energy bills during those 15 years. (Bill savings are in 1995 dollars, discounted at a 4% real discount rate.)

  18. Electricity Bill Savings from Residential Photovoltaic Systems: Sensitivities to Changes in Future Electricity Market Conditions

    SciTech Connect

    Darghouth, Naim; Barbose, Galen; Wiser, Ryan

    2013-01-09

    Customer-sited photovoltaic (PV) systems in the United States are often compensated at the customer’s underlying retail electricity rate through net metering. Calculations of the customer economics of PV, meanwhile, often assume that retail rate structures and PV compensation mechanisms will not change and that retail electricity prices will increase (or remain constant) over time, thereby also increasing (or keeping constant) the value of bill savings from PV. Given the multitude of potential changes to retail rates and PV compensation mechanisms in the future, however, understanding how such changes might impact the value of bill savings from PV is critical for policymakers, regulators, utilities, the solar industry, and potential PV owners, i.e., any stakeholder interested in understanding uncertainties in and potential changes to the long-term customer economics of PV. This scoping study investigates the impact of, and interactions among, three key sources of uncertainty in the future value of bill savings from customer-sited PV, focusing in particular on residential customers. These three sources of uncertainty are: changes to electricity market conditions that would affect retail electricity prices, changes to the types of retail rate structures available to residential customers with PV, and shifts away from standard net-metering toward other compensation mechanisms for residential PV.

  19. Energy Savings Potential of Radiative Cooling Technologies

    SciTech Connect

    Fernandez, Nicholas; Wang, Weimin; Alvine, Kyle J.; Katipamula, Srinivas

    2015-11-30

    Pacific Northwest National Laboratory (PNNL), with funding from the U.S. Department of Energy’s (DOE’s) Building Technologies Program (BTP), conducted a study to estimate, through simulation, the potential cooling energy savings that could be achieved through novel approaches to capturing free radiative cooling in buildings, particularly photonic ‘selective emittance’ materials. This report documents the results of that study.

  20. Potential cost savings with terrestrial rabies control

    PubMed Central

    Recuenco, Sergio; Cherry, Bryan; Eidson, Millicent

    2007-01-01

    Background The cost-benefit of raccoon rabies control strategies such as oral rabies vaccination (ORV) are under evaluation. As an initial quantification of the potential cost savings for a control program, the collection of selected rabies cost data was pilot tested for five counties in New York State (NYS) in a three-year period. Methods Rabies costs reported to NYS from the study counties were computerized and linked to a human rabies exposure database. Consolidated costs by county and year were averaged and compared. Results Reported rabies-associated costs for all rabies variants totalled $2.1 million, for human rabies postexposure prophylaxes (PEP) (90.9%), animal specimen preparation/shipment to laboratory (4.7%), and pet vaccination clinics (4.4%). The proportion that may be attributed to raccoon rabies control was 37% ($784,529). Average costs associated with the raccoon variant varied across counties from $440 to $1,885 per PEP, $14 to $44 per specimen, and $0.33 to $15 per pet vaccinated. Conclusion Rabies costs vary widely by county in New York State, and were associated with human population size and methods used by counties to estimate costs. Rabies cost variability must be considered in developing estimates of possible ORV-related cost savings. Costs of PEPs and specimen preparation/shipments, as well as the costs of pet vaccination provided by this study may be valuable for development of more realistic scenarios in economic modelling of ORV costs versus benefits. PMID:17407559

  1. Electric energy saving two position combination switching device

    SciTech Connect

    Andrews, P.

    1985-10-22

    In one form of the present preferred embodiment of the present invention it relates to a two-position feed-thru electric line cord piercing switching combination, of the rotary and even the rocker type, which saves electric energy by use of a half-wave diode rectifying means. The electric energy saving, two-position, combination switching means having only two electrical passing switching positions and thereby having no electrical ''off'' position. The switch will alternatingly provide either an electrical half-wave ''dim'' or an electrical full-wave ''on'' illumination to a single filament lamp, string of Christmas tree lamps and the like, and will even provide eight separate combinations, of one OFF abd three separate illuminations, when electrically connected ahead of a, for example, conventional LEVITON rotary 4-position lamp socket switching means which uses a conventional 3-way incandescent lamp member which is removable inserted into the lamp socket portion thereof. MICRO, CHERRY, toggle, rocker, push-button and the like, line cord non-piercing two-position switches may be used in other forms of the combination switching device or invention. The half-wave diode rectifying means is electrically connected shuntingly between and/or across substantially to two electrical contact members of the conductor wire-piercing and the wire non-piercing type of switching means. This construction results in automatic elimination of the electrical ''off'' position for generally any type 2 2-position ''off'' and ''on'' switching means.

  2. Ecology: Electrical Cable Bacteria Save Marine Life.

    PubMed

    Nielsen, Lars Peter

    2016-01-11

    Animals at the bottom of the sea survive oxygen depletion surprisingly often, and a new study identifies cable bacteria in the sediment as the saviors. The bacterial electrical activity creates an iron 'carpet', trapping toxic hydrogen sulfide.

  3. Energy Savings Potential and Research & Development Opportunities for Commercial Refrigeration

    SciTech Connect

    none,

    2009-09-01

    This study documents the energy consumption of commercial refrigeration equipment (CRE) in the U.S. and evaluated the energy savings potential of various technologies and energy efficiency measures that could be applied to such equipment. The study provided an overview of CRE applications, assessed the energy-savings potential of CRE in the U.S., outline key barriers to adoption of energy-savings technologies, and recommended opportunities for advanced energy saving technology research. The study was modeled after an earlier 1996 report by Arthur D. Little, Inc., and updated key information, examined more equipment types, and outlined long-term research and development opportunities.

  4. Data Network Equipment Energy Use and Savings Potential in Buildings

    SciTech Connect

    Lanzisera, Steven; Nordman, Bruce; Brown, Richard E.

    2010-06-09

    Network connectivity has become nearly ubiquitous, and the energy use of the equipment required for this connectivity is growing. Network equipment consists of devices that primarily switch and route Internet Protocol (IP) packets from a source to a destination, and this category specifically excludes edge devices like PCs, servers and other sources and sinks of IP traffic. This paper presents the results of a study of network equipment energy use and includes case studies of networks in a campus, a medium commercial building, and a typical home. The total energy use of network equipment is the product of the stock of equipment in use, the power of each device, and their usage patterns. This information was gathered from market research reports, broadband market penetration studies, field metering, and interviews with network administrators and service providers. We estimate that network equipment in the USA used 18 TWh, or about 1percent of building electricity, in 2008 and that consumption is expected to grow at roughly 6percent per year to 23 TWh in 2012; world usage in 2008 was 51 TWh. This study shows that office building network switches and residential equipment are the two largest categories of energy use consuming 40percent and 30percent of the total respectively. We estimate potential energy savings for different scenarios using forecasts of equipment stock and energy use, and savings estimates range from 20percent to 50percent based on full market penetration of efficient technologies.

  5. Streamlining Shor's algorithm for potential hardware savings

    NASA Astrophysics Data System (ADS)

    Nam, Y. S.; Blümel, R.

    2013-06-01

    We constructed a virtual quantum computer by running a complete, scaling, quantum-gate-by-quantum-gate implementation of Shor's algorithm on a 128-core classical cluster computer. In mode A [quantum period finding (PF) only, supplied with classical results for the modular exponentiation (ME) part of Shor's algorithm], factoring semiprimes up to N=557993 with up to n=39 qubits, we confirm earlier, smaller-n results concerning the performance scaling of Shor's algorithm equipped with a truncated (banded) quantum Fourier transform. Running our virtual quantum computer in mode B (full quantum implementation of ME and PF), we find that a large number of gates may be discarded in a scalable way in both the ME and PF parts of Shor's algorithm in exchange for only a small reduction in performance. We explicitly state the associated scaling laws. Implying significant savings in quantum gates, we suggest that these results are of importance for future experimental and technical large-n implementations of quantum computers.

  6. Potential energy savings from aquifer thermal energy storage

    SciTech Connect

    Anderson, M.R.; Weijo, R.O.

    1988-07-01

    Pacific Northwest Laboratory researchers developed an aggregate-level model to estimate the short- and long-term potential energy savings from using aquifer thermal storage (ATES) in the United States. The objectives of this effort were to (1) develop a basis from which to recommend whether heat or chill ATES should receive future research focus and (2) determine which market sector (residential, commercial, or industrial) offers the largest potential energy savings from ATES. Information was collected on the proportion of US land area suitable for ATES applications. The economic feasibility of ATES applications was then evaluated. The potential energy savings from ATES applications was calculated. Characteristic energy use in the residential, commercial, and industrial sectors was examined, as was the relationship between waste heat production and consumption by industrial end-users. These analyses provided the basis for two main conclusions: heat ATES applications offer higher potential for energy savings than do chill ATES applications; and the industrial sector can achieve the highest potential energy savings for the large consumption markets. Based on these findings, it is recommended that future ATES research and development efforts be directed toward heat ATES applications in the industrial sector. 11 refs., 6 figs., 9 tabs.

  7. Electricity savings from residential appliance standards in Sweden

    SciTech Connect

    Turiel, I.; Lebot, B.

    1993-04-01

    This paper discusses the energy savings that could be obtained in Sweden by instituting specific standards for five appliances: Refrigerators, freezers, dishwashers, clothes washers, and clothes dryers. At the present time, Sweden has no minimum energy efficiency standards for residential appliances. This paper discusses the energy savings that could be obtained by instituting specific standards for five product types (refrigerators, freezers, dishwashers, clothes washers, and dryers) starting in 1995. A methodology similar to that used in analyses for the European Community was employed in this study. In the Swedish study, we used appliance test data developed by the Swedish consumer agency, Konsument Verket, to estimate new unit energy consumption for each product type. Shipments, saturations, energy use, and demographic data were input to a spreadsheet model that sums energy consumption for each product type over the period 1990--2010. Both a base case and a standards case scenario are simulated for each of the five appliance types. It was found that electricity use for these five products can be reduced by 12% over the time period from 1990--2010. Most of the energy savings come from instituting efficiency standards for refrigerators and freezers. For each product class type, the impact on manufacturer offerings is discussed. For example, for simple refrigerators, eleven 1990 models meet the 1995 standard and six models meet the 2000 standard out of a total of 63 models.

  8. Cooling energy savings potential of light-colored roofs for residential and commercial buildings in 11 US metropolitan areas

    SciTech Connect

    Konopacki, S.; Akbari, H.; Pomerantz, M.; Gabersek, S.; Gartland, L.

    1997-05-01

    Light-colored roofs reflect more sunlight than dark roofs, thus they keep buildings cooler and reduce air-conditioning demand. Typical roofs in the United States are dark, which creates a potential for savings energy and money by changing to reflective roofs. In this report, the authors make quantitative estimates of the impact of roof color by simulating prototypical buildings with light- and dark-colored roofs and calculating savings by taking the differences in annual cooling and heating energy use, and peak electricity demand. Monetary savings are calculated using local utility rates. Savings are estimated for 11 U.S. Metropolitan Statistical Areas (MSAs) in a variety of climates.

  9. Electrical potentials in stomatal complexes

    SciTech Connect

    Saftner, R.A.; Raschke, K.

    1981-06-01

    Guard cells of several species, but predominantly Commelina communis, were impaled by micropipette electrodes and potential differences measured that occurred between cell compartments and the flowing bathing medium. The wall developed a Donnan potential that was between -60 and -70 millivolt in 30 millimolar KC1 at pH 7. The density of the fixed charges ranged from 0.3 to 0.5 molar; its dependence on pH was almost identical with the titration curve of authentic polygalacturonic acid. The vacuolar potential of guard cells of Commelina communis L., Zea mays L., Nicotiana glauca Graham, Allium cepa L., and Vicia faba L. was between -40 and -50 millivolt in 30 millimolar KCl when stomata were open and about -30 millivolt when stomata were closed. The vacuolar potential of guard cells of C. communis was almost linearly related to stomatal aperture and responded to changes in the ionic strength in the bathing medium in a Nernstian manner. No specificity for any alkali ion (except Li/sup +/), ammonium, or choline appeared. Lithium caused hyperpolarization. Calcium in concentrations between 1 and 100 millimolar in the medium led to stomatal closure, also caused hyperpolarization, and triggered transient oscillations in the intracellular potential. Gradients in the electrical potential existed across stomatal complexes with open pores. When stomata closed, these gradients almost disappeared or slightly reverted; all epidermal cells were then at potentials near -30 millivolt in 30 millimolar KCl.

  10. Energy savings potential in air conditioners and chiller systems

    DOE PAGES

    Kaya, Durmus; Alidrisi, Hisham

    2014-01-22

    In the current paper we quantified and evaluated the energy saving potential in air conditioners and chiller systems. Here, we also showed how to reduce the cost of air conditioners and chiller systems in existing facilities on the basis of payback periods. Among the measures investigated were: (1) installing higher efficiency air conditioners, (2) installing higher efficiency chillers, (3) duty cycling air conditioning units, and (4) utilizing existing economizers on air conditioning units. For each method, examples were provided from Arizona, USA. In these examples, the amount of saved energy, the financial evaluation of this energy, and the investment costmore » and pay back periods were calculated.« less

  11. Energy savings potential in air conditioners and chiller systems

    SciTech Connect

    Kaya, Durmus; Alidrisi, Hisham

    2014-01-22

    In the current paper we quantified and evaluated the energy saving potential in air conditioners and chiller systems. Here, we also showed how to reduce the cost of air conditioners and chiller systems in existing facilities on the basis of payback periods. Among the measures investigated were: (1) installing higher efficiency air conditioners, (2) installing higher efficiency chillers, (3) duty cycling air conditioning units, and (4) utilizing existing economizers on air conditioning units. For each method, examples were provided from Arizona, USA. In these examples, the amount of saved energy, the financial evaluation of this energy, and the investment cost and pay back periods were calculated.

  12. Fuel savings potential of the NASA Advanced Turboprop Program

    SciTech Connect

    Whitlow, J.B. Jr.; Sievers, G.K.

    1984-01-01

    The NASA Advanced Turboprop (ATP) Program is directed at developing new technology for highly loaded, multibladed propellers for use at Mach 0.65 to 0.85 and at altitudes compatible with the air transport system requirements. Advanced turboprop engines offer the potential of 15 to 30 percent savings in aircraft block fuel relative to advanced turbofan engines (50 to 60 percent savings over today's turbofan fleet). The concept, propulsive efficiency gains, block fuel savings and other benefits, and the program objectives through a systems approach are described. Current program status and major accomplishments in both single rotation and counter rotation propeller technology are addressed. The overall program from scale model wind tunnel tests to large scale flight tests on testbed aircraft is discussed.

  13. Electrical Potentials during Gravitropism in Bean Epicotyls

    PubMed Central

    Imagawa, Kazuyuki; Toko, Kiyoshi; Ezaki, Shu; Hayashi, Kenshi; Yamafuji, Kaoru

    1991-01-01

    An apparatus for measuring simultaneously the surface electrical potentials along epicotyl was developed to study the largely bending situation by gravity. Potentials increased on the upper side and decreased on the lower side after the horizontal placement. The time course of electrical changes consisted of two components which correspond to growth movements observed during gravitropism. PMID:16668370

  14. Estimating customer electricity savings from projects installed by the U.S. ESCO industry

    SciTech Connect

    Carvallo, Juan Pablo; Larsen, Peter H.; Goldman, Charles A.

    2014-11-25

    The U.S. energy service company (ESCO) industry has a well-established track record of delivering substantial energy and dollar savings in the public and institutional facilities sector, typically through the use of energy savings performance contracts (ESPC) (Larsen et al. 2012; Goldman et al. 2005; Hopper et al. 2005, Stuart et al. 2013). This ~$6.4 billion industry, which is expected to grow significantly over the next five years, may play an important role in achieving demand-side energy efficiency under local/state/federal environmental policy goals. To date, there has been little or no research in the public domain to estimate electricity savings for the entire U.S. ESCO industry. Estimating these savings levels is a foundational step in order to determine total avoided greenhouse gas (GHG) emissions from demand-side energy efficiency measures installed by U.S. ESCOs. We introduce a method to estimate the total amount of electricity saved by projects implemented by the U.S. ESCO industry using the Lawrence Berkeley National Laboratory (LBNL) /National Association of Energy Service Companies (NAESCO) database of projects and LBNL’s biennial industry survey. We report two metrics: incremental electricity savings and savings from ESCO projects that are active in a given year (e.g., 2012). Overall, we estimate that in 2012 active U.S. ESCO industry projects generated about 34 TWh of electricity savings—15 TWh of these electricity savings were for MUSH market customers who did not rely on utility customer-funded energy efficiency programs (see Figure 1). This analysis shows that almost two-thirds of 2012 electricity savings in municipal, local and state government facilities, universities/colleges, K-12 schools, and healthcare facilities (i.e., the so-called “MUSH” market) were not supported by a utility customer-funded energy efficiency program.

  15. Savings Potential of ENERGY STAR(R) External Power Adapters andBattery Chargers

    SciTech Connect

    Webber, Carrie; Korn, David; Sanchez, Marla

    2007-02-28

    External power adapters may lose 10 to 70 percent of theenergy they consume, dissipated as heat rather than converted into usefulenergy. Battery charging systems have more avenues for losses: inaddition to power conversion losses, power is consumed by the chargingcircuitry, and additional power may be needed after the battery is fullcharged to balance self-discharge. In 2005, the Environmental ProtectionAgency launched a new ENERGY STAR(R) label for external power supplies(EPSs) that convert line-voltage AC electricity into low-voltage DCelectricity for certain electronic devices. The specification includedpower supplies for products with battery charging functions (e.g. laptopsand cell phones), but excluded others. In January 2006, a separatespecification was issued for battery charging systems contained primarilyin small household appliances and power tools. In addition to the ENERGYSTAR(R) label, the state of California will implement minimum energyperformance standards for EPSs in 2007, and similar standards for EPSsand battery chargers are in development at the national level.Many of theproducts covered by these policies use relatively little power and havemodest per-unit savings potential compared to conventional energyefficiency targets. But with an estimated 1.5 billion adapters and 230million battery charging systems in use in the United States, theaggregate savings potential is quite high. This paper presents estimatesof the savings potential for external power adapters and battery chargingsystems through 2025.

  16. Bandwidth Study on Energy Use and Potential Energy Saving Opportunities in U.S. Chemical Manufacturing

    SciTech Connect

    Sabine Brueske, Caroline Kramer, Aaron Fisher

    2015-06-01

    Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. chemical manufacturing. The study relies on multiple sources to estimate the energy used in the production of 74 individual chemicals, representing 57% of sector-wide energy consumption. Energy savings opportunities for individual chemicals and for 15 subsectors of chemicals manufacturing are based on technologies currently in use or under development; these potential savings are then extrapolated to estimate sector-wide energy savings opportunity.

  17. Bandwidth Study on Energy Use and Potential Energy Savings Opportunities in U.S. Petroleum Refining

    SciTech Connect

    Sabine Brueske, Caroline Kramer, Aaron Fisher

    2015-06-01

    Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. petroleum refining. The study relies on multiple sources to estimate the energy used in nine individual process areas, representing 68% of sector-wide energy consumption. Energy savings opportunities for individual processes are based on technologies currently in use or under development; these potential savings are then extrapolated to estimate sector-wide energy savings opportunity.

  18. Potential for energy savings in old and new auto engines

    NASA Astrophysics Data System (ADS)

    Reitz, John R.

    1985-11-01

    This paper disucsses the potential for energy savings in the transportation sector through the use of both improved and entirely new automotive engines. Although spark-ignition and diesel internal combustion engines will remain the dominant choices for passenger-car use throughout the rest of this century, improved versions of these engines (lean-burn, low-friction spark-ignition and adiabatic, low-friction diesel engines) could, in the long term, provide a 20-30 percent improvement in fuel economy over what is currently available. The use of new materials, and modifications to both vehicle structure and vehicle transmissions may yield further improvements. Over a longer time frame, the introduction of the high-temperature gas-turbine engine and the use of new synfuels may provide further opportunities for energy conservation.

  19. Gridded state maps of wind electric potential

    NASA Astrophysics Data System (ADS)

    Schwartz, M. N.; Elliott, D. L.; Gower, G. L.

    1992-10-01

    Estimates of wind electric potential and available windy land area in the contiguous United States, calculated in 1991, were revised by incorporating actual data on the distribution of environmental exclusion areas where wind energy development would be prohibited or severely restricted. The new gridded data base with actual environmental exclusion areas, in combination with a 'moderate' land-use scenario, is the basis for developing the first gridded maps of available windy land and wind electric potential. Gridded maps for the 48 contiguous states show the estimated windy land area and electric potential for each grid cell (1/40 latitude by 1/30 longitude). These new maps show the distribution of the estimated wind electric potential and available windy land within an individual state, unlike previous national maps that only show estimates of the total wind electric potential for the state as a whole. While changes for some individual states are fairly large (in percentage), on a national basis, the estimated windy land area and wind electric potential are only about 1 - 2 percent higher than estimated in 1991.

  20. Origin of auroral electric potential structures

    NASA Astrophysics Data System (ADS)

    Chiu, Y. T.

    Available observational data and theoretical models of the formation of auroral electric potential structures are reviewed. It is shown that the principle of arc formation in the aurora can also be applied to other geomagnetic configurations, in order to construct a comprehensive theory of discrete auroral arcs. According to the theory, the completion of the field-aligned current circuit in the aurora can lead to downward parallel electric fields in the return current from the central region of discrete arc potential. It is pointed out that evidence for downward parallel electric field signatures has been collected within the last year.

  1. A simple tool for estimating city-wide annual electrical energy savings from cooler surfaces

    SciTech Connect

    Pomerantz, Melvin; Rosado, Pablo J.; Levinson, Ronnen M.

    2015-06-27

    We present a simple method to estimate the maximum possible electrical energy saving that might be achieved by increasing the albedo of surfaces in a large city. We restrict this to the “indirect effect”, the cooling of outside air that lessens the demand for air conditioning (AC). Given the power demand of the electric utilities and data about the city, we can use a single linear equation to estimate the maximum savings. For example, the result for an albedo change of 0.2 of pavements in a typical warm city in California, such as Sacramento, is that the saving is less than about 2 kWh per m2 per year. This may help decision makers choose which heat island mitigation techniques are economical from an energy-saving perspective.

  2. Analysis on factors affecting household customers decision in using electricity at peak time and its correlation towards saving electricity

    NASA Astrophysics Data System (ADS)

    Pasasa, Linus; Marbun, Parlin; Mariza, Ita

    2015-09-01

    The purpose of this paper is to study and analyse the factors affecting customer decisions in using electricity at peak-load hours (between 17.00 to 22.00 WIB) and their behaviors towards electricity conservation in Indonesian household. The underlying rationale is to influence a reduction in energy consumption by stimulating energy saving behaviors, thereby reducing the impact of energy use on the environment. How is the correlation between the decisions in using electricity during peak load hours with the household customer's behavior towards saving electricity? The primary data is obtained by distributing questionnaires to customers of PT. PLN Jakarta Raya and Tangerang Distribution from Household segment. The data is analysed using the Structural Equation Model (SEM) and AMOS Software. The research is finding that all factors (Personal, Social, PLN Services, Psychological, and Cultural) are positively influence customer decision in using electricity at peak load hours. There is a correlation between the decisions in using electricity during peak load hours with the household customer's behavior towards saving electricity.

  3. Advertising energy saving programs: The potential environmental cost of emphasizing monetary savings.

    PubMed

    Schwartz, Daniel; Bruine de Bruin, Wändi; Fischhoff, Baruch; Lave, Lester

    2015-06-01

    Many consumers have monetary or environmental motivations for saving energy. Indeed, saving energy produces both monetary benefits, by reducing energy bills, and environmental benefits, by reducing carbon footprints. We examined how consumers' willingness and reasons to enroll in energy-savings programs are affected by whether advertisements emphasize monetary benefits, environmental benefits, or both. From a normative perspective, having 2 noteworthy kinds of benefit should not decrease a program's attractiveness. In contrast, psychological research suggests that adding external incentives to an intrinsically motivating task may backfire. To date, however, it remains unclear whether this is the case when both extrinsic and intrinsic motivations are inherent to the task, as with energy savings, and whether removing explicit mention of extrinsic motivation will reduce its importance. We found that emphasizing a program's monetary benefits reduced participants' willingness to enroll. In addition, participants' explanations about enrollment revealed less attention to environmental concerns when programs emphasized monetary savings, even when environmental savings were also emphasized. We found equal attention to monetary motivations in all conditions, revealing an asymmetric attention to monetary and environmental motives. These results also provide practical guidance regarding the positioning of energy-saving programs: emphasize intrinsic benefits; the extrinsic ones may speak for themselves. PMID:25581089

  4. Advertising energy saving programs: The potential environmental cost of emphasizing monetary savings.

    PubMed

    Schwartz, Daniel; Bruine de Bruin, Wändi; Fischhoff, Baruch; Lave, Lester

    2015-06-01

    Many consumers have monetary or environmental motivations for saving energy. Indeed, saving energy produces both monetary benefits, by reducing energy bills, and environmental benefits, by reducing carbon footprints. We examined how consumers' willingness and reasons to enroll in energy-savings programs are affected by whether advertisements emphasize monetary benefits, environmental benefits, or both. From a normative perspective, having 2 noteworthy kinds of benefit should not decrease a program's attractiveness. In contrast, psychological research suggests that adding external incentives to an intrinsically motivating task may backfire. To date, however, it remains unclear whether this is the case when both extrinsic and intrinsic motivations are inherent to the task, as with energy savings, and whether removing explicit mention of extrinsic motivation will reduce its importance. We found that emphasizing a program's monetary benefits reduced participants' willingness to enroll. In addition, participants' explanations about enrollment revealed less attention to environmental concerns when programs emphasized monetary savings, even when environmental savings were also emphasized. We found equal attention to monetary motivations in all conditions, revealing an asymmetric attention to monetary and environmental motives. These results also provide practical guidance regarding the positioning of energy-saving programs: emphasize intrinsic benefits; the extrinsic ones may speak for themselves.

  5. Global potential for wind-generated electricity

    PubMed Central

    Lu, Xi; McElroy, Michael B.; Kiviluoma, Juha

    2009-01-01

    The potential of wind power as a global source of electricity is assessed by using winds derived through assimilation of data from a variety of meteorological sources. The analysis indicates that a network of land-based 2.5-megawatt (MW) turbines restricted to nonforested, ice-free, nonurban areas operating at as little as 20% of their rated capacity could supply >40 times current worldwide consumption of electricity, >5 times total global use of energy in all forms. Resources in the contiguous United States, specifically in the central plain states, could accommodate as much as 16 times total current demand for electricity in the United States. Estimates are given also for quantities of electricity that could be obtained by using a network of 3.6-MW turbines deployed in ocean waters with depths <200 m within 50 nautical miles (92.6 km) of closest coastlines. PMID:19549865

  6. Global potential for wind-generated electricity.

    PubMed

    Lu, Xi; McElroy, Michael B; Kiviluoma, Juha

    2009-07-01

    The potential of wind power as a global source of electricity is assessed by using winds derived through assimilation of data from a variety of meteorological sources. The analysis indicates that a network of land-based 2.5-megawatt (MW) turbines restricted to nonforested, ice-free, nonurban areas operating at as little as 20% of their rated capacity could supply >40 times current worldwide consumption of electricity, >5 times total global use of energy in all forms. Resources in the contiguous United States, specifically in the central plain states, could accommodate as much as 16 times total current demand for electricity in the United States. Estimates are given also for quantities of electricity that could be obtained by using a network of 3.6-MW turbines deployed in ocean waters with depths <200 m within 50 nautical miles (92.6 km) of closest coastlines.

  7. [Measurements of electric membrane potentials in lymphocytes].

    PubMed

    Kowal, E; Malofiejew, M; Kostrzewska, A

    1975-01-01

    The interior of vital lymphocytes, as opposed to their outer environment, has a negative electric potential (rest potential), the magnitude of which depends on the potassium ion concentration of the extracellular medium. The bioelectric phenomena at the lymphocyte are determined not only by the functional state of the cell membrane, but also by the milieu of the blood cells which includes also the adsorbed proteins and lipids. PMID:1199616

  8. Thunderstorm Electric Potential Profiles: Electrical Evolution and Lightning Energy

    NASA Astrophysics Data System (ADS)

    Stolzenburg, M.; Marshall, T. C.

    2005-05-01

    From a balloon sounding of electric field through a thunderstorm, one can calculate the vertical profile of potential, V, within the storm. In this presentation we investigate thunderstorm electrical evolution by examining V profiles through various stages of a storm's life. We present data from New Mexico mountain thunderstorms in which we made a series of 4 to 6 balloon soundings. Several of the successive V profiles in the same storm are quite similar, in spite of the numerous lightning flashes that occurred during the balloon flights. These similarities suggest that the V profiles are reasonable estimates of the in-cloud potential. The similar profiles occur during the mature phase of the storm, and mature phase profiles are even similar from one storm to another. This is true despite different lightning flashing rates and, presumably, different charge generation rates in the different storms. Another result of this work is that potential profiles during the early and late stages of the storm do not resemble those from the mature stage. Recently, Coleman et al. [2003] showed that intra-cloud (IC) flashes connect potential extrema of opposite polarity and that normal (negative) cloud-to-ground (CG) flashes connect a potential minimum to ground. Thus we can use the V profiles to estimate the potential difference spanned by lightning flashes during the evolution of the storm and, with this, estimate the lightning energy. Typical potential differences spanned by IC and CG flashes will be presented from four storms. Reference: Coleman, L.M., T.C. Marshall, M. Stolzenburg, T. Hamlin, P.R. Krehbiel, W. Rison, and R.J. Thomas, Effects of charge and electrostatic potential on lightning propagation, J. Geophys. Res., 108, doi:10.1029/2002JD002718, 2003.

  9. Water savings potentials of irrigation systems: dynamic global simulation

    NASA Astrophysics Data System (ADS)

    Jägermeyr, J.; Gerten, D.; Heinke, J.; Schaphoff, S.; Kummu, M.; Lucht, W.

    2015-04-01

    Global agricultural production is heavily sustained by irrigation, but irrigation system efficiencies are often surprisingly low. However, our knowledge of irrigation efficiencies is mostly confined to rough indicative estimates for countries or regions that do not account for spatio-temporal heterogeneity due to climate and other biophysical dependencies. To allow for refined estimates of global agricultural water use, and of water saving and water productivity potentials constrained by biophysical processes and also non-trivial downstream effects, we incorporated a dynamic representation of the three major irrigation systems (surface, sprinkler, and drip) into a process-based bio- and agrosphere model, LPJmL. Based on this enhanced model we provide a gridded worldmap of dynamically retrieved irrigation efficiencies reflecting differences in system types, crop types, climatic and hydrologic conditions, and overall crop management. We find pronounced regional patterns in beneficial irrigation efficiency (a refined irrigation efficiency indicator accounting for crop-productive water consumption only), due to differences in these features, with lowest values (< 30%) in South Asia and Sub-Saharan Africa and highest values (> 60%) in Europe and North America. We arrive at an estimate of global irrigation water withdrawal of 2396 km3 (2004-2009 average); irrigation water consumption is calculated to be 1212 km3, of which 511 km3 are non-beneficially consumed, i.e. lost through evaporation, interception, and conveyance. Replacing surface systems by sprinkler or drip systems could, on average across the world's river basins, reduce the non-beneficial consumption at river basin level by 54 and 76%, respectively, while maintaining the current level of crop yields. Accordingly, crop water productivity would increase by 9 and 15%, respectively, and by much more in specific regions such as in the Indus basin. This study significantly advances the global quantification of

  10. Energy savings potential from energy-conserving irrigation systems

    SciTech Connect

    Wilfert, G.L.; Patton, W.P.; Harrer, B.J.; Clark, M.A.

    1982-11-01

    This report systematically compares, within a consistent framework, the technical and economic characteristics of energy-conserving irrigation systems with those of conventional irrigation systems and to determine total energy savings. Levelized annual costs of owning and operating both energy-conserving and conventional irrigation systems have been developed and compared for all 17 states to account for the differences in energy costs and irrigation conditions in each state. Market penetration of energy-conserving systems is assessed for those systems having lower levelized annual costs than conventional systems performing the same function. Annual energy savings were computed by matching the energy savings per system with an assumed maximum market penetration of 100 percent in those markets where the levelized annual costs of energy-conserving systems are lower than the levelized annual costs of conventional systems.

  11. Electrical Monitoring Devices Save on Time and Cost

    NASA Technical Reports Server (NTRS)

    2015-01-01

    In order to protect the Solar Dynamics Observatory's instruments from blowing their fuses and being rendered unusable, Goddard Space Flight Center worked with Micropac Industries Inc., based in Garland, Texas, to develop solid-state power controllers, which can depower and then resupply power to an instrument in the event of an electric surge. The company is now selling the technology for use in industrial plants.

  12. Potential for biomass electricity in four Asian countries

    SciTech Connect

    Kinoshita, C.M.; Turn, S.Q.; Tantlinger, J.; Kaya, M.

    1997-12-31

    Of all forms of renewable energy, biomass offers the best near-term opportunity for supplying a significant portion of the world`s need for electric power. Biomass is especially competitive when fuel supply costs are partially defrayed as production activities associated with the processing of another product, e.g., sugar, rice, or vegetable oil. Not only do such processing situations provide cost savings, they also generate very large supplies of fuel and therefore can contribute significantly to the local energy mix. Access to ample supplies of competitively-priced biomass feedstocks is only one of several factors needed to encourage the use of biomass for power generation; equally important is a healthy market for electricity, i.e., need for large blocks of additional power and sufficient strength in the economy to attract investment in new capacity. Worldwide, the Asia-Pacific region is projected to have the greatest need for new generating capacity in the next decade and shows the highest rate of economic growth, making it an attractive market for biomass power. Also critical to the expansion of bioenergy is the adoption of positive, stable policies on energy production, distribution, and sale, that encourage the generation and use of electricity from biomass. The aforementioned three factors--adequate biomass supplies, increasing demand for electricity, and supportive policies--are examined for four Asian countries, the Philippines, Thailand, Malaysia, and Indonesia. Information presented for each of the four countries include the types and amounts of bioresidues and their associated electric power generation potential; present and future supplies and demand for electricity; and existing or planned government and utility policies that could impact the generation and use of biomass power.

  13. Potential for the Use of Energy Savings Performance Contracts to Reduce Energy Consumption and Provide Energy and Cost Savings in Non-Building Applications

    SciTech Connect

    Williams, Charles; Green, Andrew S.; Dahle, Douglas; Barnett, John; Butler, Pat; Kerner, David

    2013-08-01

    The findings of this study indicate that potential exists in non-building applications to save energy and costs. This potential could save billions of federal dollars, reduce reliance on fossil fuels, increase energy independence and security, and reduce greenhouse gas emissions. The Federal Government has nearly twenty years of experience with achieving similar energy cost reductions, and letting the energy costs savings pay for themselves, by applying energy savings performance contracts (ESPC) inits buildings. Currently, the application of ESPCs is limited by statute to federal buildings. This study indicates that ESPCs can be a compatible and effective contracting tool for achieving savings in non-building applications.

  14. Energy saving potential of residential HVAC options at Fort Irwin, California

    SciTech Connect

    Hadley, D.L.; Stucky, D.J.

    1995-03-01

    The Pacific Northwest Laboratory (PNL) evaluated heating and cooling system options for existing family housing at Fort Irwin, California. The purpose of this work was to quantify the energy conservation potential of alternative system types and to identify the most cost-effective technology available. The conventional residential heating/cooling systems at Fort Irwin are separate propane forced-air furnaces and central air conditioners. The options examined included air- and ground-source heat pumps, a natural gas furnace with central air conditioning, and a natural-gas-fired heat pump. The most cost-effective technology applicable to Fort Irwin was found to be the high-efficiency ground-source heat pumps. If all conventional units were replaced immediately, the net energy savings would be 76,660 MBtu (80.9 TJ) per year and a reduction in electrical demand of approximately 15,000 kW-month. The initial investment for implementing this technology would be approximately $7.1 million, with a savings-to-investment ratio of 1.74.

  15. Improving Light Distribution by Zoom Lens for Electricity Savings in a Plant Factory with Light-Emitting Diodes.

    PubMed

    Li, Kun; Li, Zhipeng; Yang, Qichang

    2016-01-01

    The high energy consumption of a plant factory is the biggest issue in its rapid expansion, especially for lighting electricity, which has been solved to a large extent by light-emitting diodes (LED). However, the remarkable potential for further energy savings remains to be further investigated. In this study, an optical system applied just below the LED was designed. The effects of the system on the growth and photosynthesis of butterhead lettuce (Lactuca sativa var. capitata) were examined, and the performance of the optical improvement in energy savings was evaluated by comparison with the traditional LED illumination mode. The irradiation patterns used were LED with zoom lenses (Z-LED) and conventional non-lenses LED (C-LED). The seedlings in both treatments were exposed to the same light environment over the entire growth period. The improvement saved over half of the light source electricity, while prominently lowering the temperature. Influenced by this, the rate of photosynthesis sharply decreased, causing reductions in plant yield and nitrate content, while having no negative effects on morphological parameters and photosynthetic pigment contents. Nevertheless, the much higher light use efficiency of Z-LEDs makes this system a better approach to illumination in a plant factory with artificial lighting. PMID:26904062

  16. Improving Light Distribution by Zoom Lens for Electricity Savings in a Plant Factory with Light-Emitting Diodes

    PubMed Central

    Li, Kun; Li, Zhipeng; Yang, Qichang

    2016-01-01

    The high energy consumption of a plant factory is the biggest issue in its rapid expansion, especially for lighting electricity, which has been solved to a large extent by light-emitting diodes (LED). However, the remarkable potential for further energy savings remains to be further investigated. In this study, an optical system applied just below the LED was designed. The effects of the system on the growth and photosynthesis of butterhead lettuce (Lactuca sativa var. capitata) were examined, and the performance of the optical improvement in energy savings was evaluated by comparison with the traditional LED illumination mode. The irradiation patterns used were LED with zoom lenses (Z-LED) and conventional non-lenses LED (C-LED). The seedlings in both treatments were exposed to the same light environment over the entire growth period. The improvement saved over half of the light source electricity, while prominently lowering the temperature. Influenced by this, the rate of photosynthesis sharply decreased, causing reductions in plant yield and nitrate content, while having no negative effects on morphological parameters and photosynthetic pigment contents. Nevertheless, the much higher light use efficiency of Z-LEDs makes this system a better approach to illumination in a plant factory with artificial lighting. PMID:26904062

  17. Improving Light Distribution by Zoom Lens for Electricity Savings in a Plant Factory with Light-Emitting Diodes.

    PubMed

    Li, Kun; Li, Zhipeng; Yang, Qichang

    2016-01-01

    The high energy consumption of a plant factory is the biggest issue in its rapid expansion, especially for lighting electricity, which has been solved to a large extent by light-emitting diodes (LED). However, the remarkable potential for further energy savings remains to be further investigated. In this study, an optical system applied just below the LED was designed. The effects of the system on the growth and photosynthesis of butterhead lettuce (Lactuca sativa var. capitata) were examined, and the performance of the optical improvement in energy savings was evaluated by comparison with the traditional LED illumination mode. The irradiation patterns used were LED with zoom lenses (Z-LED) and conventional non-lenses LED (C-LED). The seedlings in both treatments were exposed to the same light environment over the entire growth period. The improvement saved over half of the light source electricity, while prominently lowering the temperature. Influenced by this, the rate of photosynthesis sharply decreased, causing reductions in plant yield and nitrate content, while having no negative effects on morphological parameters and photosynthetic pigment contents. Nevertheless, the much higher light use efficiency of Z-LEDs makes this system a better approach to illumination in a plant factory with artificial lighting.

  18. Analysis of Potential Energy Saving and CO2 Emission Reduction of Home Appliances and Commercial Equipments in China

    SciTech Connect

    Zhou, Nan; Fridley, David; McNeil, Michael; Zheng, Nina; Letschert, Virginie; Ke, Jing

    2011-04-01

    China has implemented a series of minimum energy performance standards (MEPS) for over 30 appliances, voluntary energy efficiency label for 40 products and a mandatory energy information label that covers 19 products to date. However, the impact of these programs and their savings potential has not been evaluated on a consistent basis. This paper uses modeling to estimate the energy saving and CO{sub 2} emission reduction potential of the appliances standard and labeling program for products for which standards are currently in place, under development or those proposed for development in 2010 under three scenarios that differ in the pace and stringency of MEPS development. In addition to a baseline 'Frozen Efficiency' scenario at 2009 MEPS level, the 'Continued Improvement Scenario' (CIS) reflects the likely pace of post-2009 MEPS revisions, and the likely improvement at each revision step. The 'Best Practice Scenario' (BPS) examined the potential of an achievement of international best practice efficiency in broad commercial use today in 2014. This paper concludes that under 'CIS', cumulative electricity consumption could be reduced by 9503 TWh, and annual CO{sub 2} emissions of energy used for all 37 products would be 16% lower than in the frozen efficiency scenario. Under a 'BPS' scenario for a subset of products, cumulative electricity savings would be 5450 TWh and annual CO{sub 2} emissions reduction of energy used for 11 appliances would be 35% lower.

  19. Cooling energy savings potential of light-colored roofs for residential and commercial buildings in 11 US metropolitan areas

    SciTech Connect

    Konopacki, S.; Akbari, H.; Gartland, L.

    1997-05-01

    The U.S. Environmental Protection Agency (EPA) sponsored this project to estimate potential energy and monetary savings resulting from the implementation of light-colored roofs on residential and commercial buildings in major U.S. metropolitan areas. Light-colored roofs reflect more sunlight than dark roofs, so they keep buildings cooler and reduce air-conditioning demand. Typically, rooftops in the United States are dark, and thus there is a potential for saving energy and money by changing to reflective roofs. Naturally, the expected savings are higher in southern, sunny, and cloudless climates. In this study, we make quantitative estimates of reduction in peak power demand and annual cooling electricity use that would result from increasing the reflectivity of the roofs. Since light-colored roofs also reflect heat in the winter, the estimates of annual electricity savings are a net value corrected for the increased wintertime energy use. Savings estimates only include direct reduction in building energy use and do not account for the indirect benefit that would also occur from the reduction in ambient temperature, i.e. a reduction in the heat island effect. This analysis is based on simulations of building energy use, using the DOE-2 building energy simulation program. Our methodology starts with specifying 11 prototypical buildings: single-family residential (old and new), office (old and new), retail store (old and new), school (primary and secondary), health (hospital and nursing home), and grocery store. Most prototypes are simulated with two heating systems: gas furnace and heat pumps. We then perform DOE-2 simulations of the prototypical buildings, with light and dark roofs, in a variety of climates and obtain estimates of the energy use for air conditioning and heating.

  20. The potential cost savings of implementing an inter-utility NO{sub x} trading program

    SciTech Connect

    Siegel, S.; Kalagnanam, J.

    1995-10-01

    Technology based standards such as RACT, which require the installation of a (R)easonably (A)vailable (C)ontrol (T)echnology on a boiler by boiler basis have been the dominant factor driving electric utility NO{sub x} compliance plans. In this paper, the authors examine the cost savings of implementing NO{sub x} trading, an alternative market based strategy for reducing the emissions of nitrogen oxides (NO{sub x}) to achieve NO{sub x} reduction goals set under Title IV of the 1990 Clean Air Act. In order to estimate the potential cost savings of inter-utility NO{sub x} trading, they use a combinatorial optimization approach to identify boiler retrofits and operating parameters which yield efficient (i.e., the most cost effective) NO{sub x} abatement strategies. In their formulation, annual emissions at individual boilers which are expensive to abate may exceed RACT levels by up to a factor of two thus allowing for trades with boilers which can abate in a more cost effective manner. They constrain total emissions in a trading region to be at or below the level obtained had all the boilers adopted RACT. Increasing the flexibility with which trades can occur has two main effects: (1) the cost effectiveness of meeting an aggregate reduction goal increases and (2) the spatial distribution of emissions shift relative to what it would have been under a strict RACT based compliance strategy. They estimate the magnitude of these effects for two Eastern electric utilities making intra- and inter-utility NO{sub x} trades. Results indicate that the cost effectiveness of meeting RACT level reduction can be increased by as much as 38% under certain trading regimes.

  1. Electrical surface potential of pulmonary surfactant.

    PubMed

    Leonenko, Zoya; Rodenstein, Mathias; Döhner, Jana; Eng, Lukas M; Amrein, Matthias

    2006-11-21

    Pulmonary surfactant is a mixed lipid protein substance of defined composition that self-assembles at the air-lung interface into a molecular film and thus reduces the interfacial tension to close to zero. A very low surface tension is required for maintaining the alveolar structure. The pulmonary surfactant film is also the first barrier for airborne particles entering the lung upon breathing. We explored by frequency modulation Kelvin probe force microscopy (FM-KPFM) the structure and local electrical surface potential of bovine lipid extract surfactant (BLES) films. BLES is a clinically used surfactant replacement and here served as a realistic model surfactant system. The films were distinguished by a pattern of molecular monolayer areas, separated by patches of lipid bilayer stacks. The stacks were at positive electrical potential with respect to the surrounding monolayer areas. We propose a particular molecular arrangement of the lipids and proteins in the film to explain the topographic and surface potential maps. We also discuss how this locally variable surface potential may influence the retention of charged or polar airborne particles in the lung.

  2. Fuel Savings Potential from Future In-motion Wireless Power Transfer (WPT); NREL (National Renewable Energy Laboratory)

    SciTech Connect

    Burton, E.; Wang, L.; Gonder, J.; Brooker, A.; Konan, A.

    2015-02-10

    This presentation discusses the fuel savings potential from future in-motion wireless power transfer. There is an extensive overlap in road usage apparent across regional vehicle population, which occurs primarily on high-capacity roads--1% of roads are used for 25% of the vehicle miles traveled. Interstates and highways make up between 2.5% and 4% of the total roads within the Consolidated Statistical Areas (CSAs), which represent groupings of metropolitan and/or micropolitan statistical areas. Mileage traveled on the interstates and highways ranges from 54% in California to 24% in Chicago. Road electrification could remove range restrictions of electric vehicles and increase the fuel savings of PHEVs or HEVs if implemented on a large scale. If 1% of the road miles within a geographic area are electrified, 25% of the fuel used by a 'fleet' of vehicles enabled with the technology could be displaced.

  3. Analysis of Potential Energy Saving and CO2 Emission Reduction of Home Appliances and Commercial Equipments in China

    SciTech Connect

    Zhou, Nan; Fridley, David; McNeill, Michael; Zheng, Nina; Letschert, Virginie; Ke, Jing; Saheb, Yamina

    2010-06-07

    China is now the world's largest producer and consumer of household appliances and commercial equipment. To address the growth of electricity use of the appliances, China has implemented a series of minimum energy performance standards (MEPS) for 30 appliances, and voluntary energy efficiency label for 40 products. Further, in 2005, China started a mandatory energy information label that covers 19 products to date. However, the impact of these standard and labeling programs and their savings potential has not been evaluated on a consistent basis. This research involved modeling to estimate the energy saving and CO{sub 2} emission reduction potential of the appliances standard and labeling program for products for which standards are currently in place, or under development and those proposed for development in 2010. Two scenarios that have been developed differ primarily in the pace and stringency of MEPS development. The 'Continued Improvement Scenario' (CIS) reflects the likely pace of post-2009 MEPS revisions, and the likely improvement at each revision step considering the technical limitation of the technology. The 'Best Practice Scenario' (BPS) examined the potential of an achievement of international best practice MEPS in 2014. This paper concludes that under the 'CIS' of regularly scheduled MEPS revisions to 2030, cumulative electricity consumption could be reduced by 9503 TWh, and annual CO{sub 2} emissions would be 16% lower than in the frozen efficiency scenario. Under a 'BPS' scenario for a subset of products, cumulative electricity savings would be 5450 TWh and annual CO{sub 2} emissions reduction would be 35% lower than in the frozen scenario.

  4. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  5. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  6. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  7. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  8. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  9. Development of an Energy-Savings Calculation Methodology for Residential Miscellaneous Electric Loads: Preprint

    SciTech Connect

    Hendron, R.; Eastment, M.

    2006-08-01

    In order to meet whole-house energy savings targets beyond 50% in residential buildings, it will be essential that new technologies and systems approaches be developed to address miscellaneous electric loads (MELs). These MELs are comprised of the small and diverse collection of energy-consuming devices found in homes, including what are commonly known as plug loads (televisions, stereos, microwaves), along with all hard-wired loads that do not fit into other major end-use categories (doorbells, security systems, garage door openers). MELs present special challenges because their purchase and operation are largely under the control of the occupants. If no steps are taken to address MELs, they can constitute 40-50% of the remaining source energy use in homes that achieve 60-70% whole-house energy savings, and this percentage is likely to increase in the future as home electronics become even more sophisticated and their use becomes more widespread. Building America (BA), a U.S. Department of Energy research program that targets 50% energy savings by 2015 and 90% savings by 2025, has begun to identify and develop advanced solutions that can reduce MELs.

  10. Potential water saving through changes in European diets.

    PubMed

    Vanham, D; Hoekstra, A Y; Bidoglio, G

    2013-11-01

    This study quantifies the water footprint of consumption (WFcons) regarding agricultural products for three diets - the current diet (REF), a healthy diet (HEALTHY) and a vegetarian diet (VEG) - for the four EU zones WEST, NORTH, SOUTH and EAST. The WFcons related to the consumption of agricultural products (4265l per capita per day or lcd) accounts for 89% of the EU's total WFcons (4815lcd). The effect of diet has therefore an essential impact on the total WFcons. The current zonal WFcons regarding agricultural products is: 5875lcd (SOUTH), 4053lcd (EAST), 3761lcd (WEST) and 3197lcd (NORTH). These differences are the result of different consumption behaviours as well as different agricultural production methods and conditions. From the perspective of a healthy diet based on regional dietary guidelines, the intake of several product groups (sugar, crop oils, animal fats and meat) should be decreased and increased for others (vegetables, fruit). The WFcons regarding agricultural products for the alternative diets are the following: HEALTHY 4110lcd (-30%) and VEG 3476lcd (-41%) for SOUTH; HEALTHY 3606lcd (-11%) and VEG 2956lcd (-27%) for EAST; HEALTHY 2766lcd (-26%) and VEG 2208lcd (-41%) for WEST; HEALTHY 3091lcd (-3%) and VEG 2166lcd (-32%) for NORTH. Both the healthy and vegetarian diets thus result - consistent for all zones - in substantial WFcons reductions. The largest reduction takes place for the vegetarian diet. Indeed, a lot of water can be saved by EU citizens by a change in their diet. PMID:24096041

  11. Bandwidth Study on Energy Use and Potential Energy Saving Opportunities in U.S. Iron and Steel Manufacturing

    SciTech Connect

    Keith Jamison, Caroline Kramer, Sabine Brueske, Aaron Fisher

    2015-06-01

    Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. iron and steel manufacturing. The study relies on multiple sources to estimate the energy used in six individual process areas and select subareas, representing 82% of sector-wide energy consumption. Energy savings opportunities for individual processes and subareas are based on technologies currently in use or under development; the potential savings are then extrapolated to estimate sector-wide energy savings opportunity.

  12. Bandwidth Study on Energy Use and Potential Energy Saving Opportunities in U.S. Pulp and Paper Manufacturing

    SciTech Connect

    Sabine Brueske, Caroline Kramer, Aaron Fisher

    2015-06-01

    Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. pulp and paper manufacturing. The study relies on multiple sources to estimate the energy used in six individual process areas, representing 52% of sector-wide energy consumption. Energy savings opportunities for individual processes are based on technologies currently in use or under development; the potential savings are then extrapolated to estimate sector-wide energy savings opportunity

  13. A multisector analysis of urban irrigation and water savings potential

    NASA Astrophysics Data System (ADS)

    Bijoor, N.; Kim, H.; Famiglietti, J. S.

    2014-12-01

    Urban irrigation strains limited water supplies in semi-arid areas such as Orange County, CA, yet the quantity and controlling factors of urban irrigation are not well understood. The goals of this research are to (1) quantify and compare landscape irrigation applied by residential and commercial sectors in various retail agencies at a parcel scale (2) determine over- and under-irrigation compared to theoretical need (3) determine the climatic and socioeconomic controls on landscape irrigation. A research partnership was established between six water retail agencies in Orange County, CA representing a wide range of climatic and economic conditions. These agencies contributed between 3 and 13 years of water use data on a monthly/bimonthly basis. Irrigation depth (mm) was estimated using the "minimum month method," and landscape evapotranspiration was calculated using the Hargreaves equation for 122,345 parcels. Multiple regressions of water use were conducted with climatic and socioeconomic variables as possible explanatory variables. Single family residences accounted for the majority of urban water use. Findings from 112,192 single family residences (SFRs) show that total and indoor water use declined, though irrigation did not significantly change. Average irrigation for SFRs was 94 L/day, and a large proportion (42%) of irrigation was applied in excess to landscapes. Air temperature was found to be the primary driver of irrigation. We mapped over-irrigation relative to plant water demand to highlight areas that can be targeted for water conservation efforts. We also show the water savings that would be gained by improving the efficiency of irrigation systems. The information gained in this study would be useful for developing water use efficiency policies and/or educational programs to promote sustainable irrigation practices at the individual parcel scale.

  14. Uncertainties in the Value of Bill Savings from Behind-the-Meter, Residential Photovoltaic Systems: The Roles of Electricity Market Conditions, Retail Rate Design, and Net Metering

    NASA Astrophysics Data System (ADS)

    Darghouth, Naim Richard

    Net metering has become a widespread policy mechanism in the U.S. for supporting customer adoption of distributed photovoltaics (PV), allowing customers with PV systems to reduce their electric bills by offsetting their consumption with PV generation, independent of the timing of the generation relative to consumption. Although net metering is one of the principal drivers for the residential PV market in the U.S., the academic literature on this policy has been sparse and this dissertation contributes to this emerging body of literature. This dissertation explores the linkages between the availability of net metering, wholesale electricity market conditions, retail rates, and the residential bill savings from behind-the-meter PV systems. First, I examine the value of the bill savings that customers receive under net metering and alternatives to net metering, and the associated role of retail rate design, based on current rates and a sample of approximately two hundred residential customers of California's two largest electric utilities. I find that the bill savings per kWh of PV electricity generated varies greatly, largely attributable to the increasing block structure of the California utilities' residential retail rates. I also find that net metering provides significantly greater bill savings than alternative compensation mechanisms based on avoided costs. However, retail electricity rates may shift as wholesale electricity market conditions change. I then investigate a potential change in market conditions -- increased solar PV penetrations -- on wholesale prices in the short-term based on the merit-order effect. This demonstrates the potential price effects of changes in market conditions, but also points to a number of methodological shortcomings of this method, motivating my usage of a long-term capacity investment and economic dispatch model to examine wholesale price effects of various wholesale market scenarios in the subsequent analysis. By developing

  15. Exploring Fuel-Saving Potential of Long-Haul Truck Hybridization

    SciTech Connect

    Gao, Zhiming; LaClair, Tim J.; Smith, David E.; Daw, C. Stuart

    2015-10-01

    We report our comparisons on the simulated fuel economy for parallel, series, and dual-mode hybrid electric long-haul trucks, in addition to a conventional powertrain configuration, powered by a commercial 2010-compliant 15-L diesel engine over a freeway-dominated heavy-duty truck driving cycle. The driving cycle was obtained by measurement during normal driving conditions. The results indicated that both parallel and dual-mode hybrid powertrains were capable of improving fuel economy by 7% to 8%. But there was no significant fuel economy benefit for the series hybrid truck because of internal inefficiencies in energy exchange. When reduced aerodynamic drag and tire rolling resistance were combined with hybridization, there was a synergistic fuel economy benefit for appropriate hybrids that increased the fuel economy benefit to more than 15%. Long-haul hybrid trucks with reduced aerodynamic drag and rolling resistance offered lower peak engine loads, better kinetic energy recovery, and reduced average engine power demand. Therefore, it is expected that hybridization with load reduction technologies offers important potential fuel energy savings for future long-haul trucks.

  16. Exploring Fuel-Saving Potential of Long-Haul Truck Hybridization

    DOE PAGES

    Gao, Zhiming; LaClair, Tim J.; Smith, David E.; Daw, C. Stuart

    2015-10-01

    We report our comparisons on the simulated fuel economy for parallel, series, and dual-mode hybrid electric long-haul trucks, in addition to a conventional powertrain configuration, powered by a commercial 2010-compliant 15-L diesel engine over a freeway-dominated heavy-duty truck driving cycle. The driving cycle was obtained by measurement during normal driving conditions. The results indicated that both parallel and dual-mode hybrid powertrains were capable of improving fuel economy by 7% to 8%. But there was no significant fuel economy benefit for the series hybrid truck because of internal inefficiencies in energy exchange. When reduced aerodynamic drag and tire rolling resistance weremore » combined with hybridization, there was a synergistic fuel economy benefit for appropriate hybrids that increased the fuel economy benefit to more than 15%. Long-haul hybrid trucks with reduced aerodynamic drag and rolling resistance offered lower peak engine loads, better kinetic energy recovery, and reduced average engine power demand. Therefore, it is expected that hybridization with load reduction technologies offers important potential fuel energy savings for future long-haul trucks.« less

  17. Max Tech Appliance Design: Potential for Maximizing U.S. Energy Savings through Standards

    SciTech Connect

    Garbesi, Karina; Desroches, Louis-Benoit; Bolduc, Christopher; Burch, Gabriel; Hosseinzadeh, Griffin; Saltiel, Seth

    2011-05-06

    This study surveyed the technical potential for efficiency improvements in 150 categories of appliances and equipment representing 33 quads of primary energy use across the US economy in 2010 and (1) documented efficient product designs, (2) identified the most promising cross-cutting strategies, and (3) ranked national energy savings potential by end use. Savings were estimated using a method modeled after US Department of Energy priority-setting reports - simplified versions of the full technical and economic analyses performed for rulemakings. This study demonstrates that large savings are possible by replacing products at the end-of-life with ultra-efficient models that use existing technology. Replacing the 50 top energy-saving end-uses (constituting 30 quads of primary energy consumption in 2010) with today's best-on-market equivalents would save {approx}200 quads of US primary energy over 30 years (25% of consumption anticipated there from). For the 29 products for maximum feasible savings potential could be estimated, the savings were twice as high. These results demonstrate that pushing ultra-efficient products to market could significantly escalate carbon emission reductions and is a viable strategy for sustaining large emissions reductions through standards. The results of this analysis were used by DOE for new coverage prioritization, to identify key opportunities for product prototyping and market development, and will leverage future standards rulemakings by identifying the full scope of maximum feasible technology options. High leverage products include advances lighting systems, HVAC, and televisions. High leverage technologies include electronic lighting, heat pumps, variable speed motors, and a host of controls-related technologies.

  18. The Oklahoma Field Test: Air-conditioning electricity savings from standard energy conservation measures, radiant barriers, and high-efficiency window air conditioners

    SciTech Connect

    Ternes, M.P.; Levins, W.P.

    1992-08-01

    A field test Involving 104 houses was performed in Tulsa, Oklahoma, to measure the air-conditioning electricity consumption of low-income houses equipped with window air conditioners, the reduction in this electricity consumption attributed to the installation of energy conservation measures (ECMS) as typically installed under the Oklahoma Weatherization Assistance Program (WAP), and the reduction achieved by the replacement of low-efficiency window air conditioners with high-efficiency units and the installation of attic radiant barriers. Air-conditioning electricity consumption and indoor temperature were monitored weekly during the pre-weatherization period (June to September 1988) and post-weatherization period (May to September 1989). House energy consumption models and regression analyses were used to normalize the air-conditioning electricity savings to average outdoor temperature conditions and the pre-weatherization indoor temperature of each house. The following conclusions were drawn from the study: (1) programs directed at reducing air-conditioning electricity consumption should be targeted at clients with high consumption to improve cost effectiveness; (2) replacing low-efficiency air conditioners with high-efficiency units should be considered an option in a weatherization program directed at reducing air-conditioning electricity consumption; (3) ECMs currently being installed under the Oklahoma WAP (chosen based on effectiveness at reducing space-heating energy consumption) should continue to be justified based on their space-heating energy savings potential only; and (4) attic radiant barriers should not be included in the Oklahoma WAP if alternatives with verified savings are available or until further testing demonstrates energy savings or other benefits in this typo of housing.

  19. Corning Inc.: Proposed Changes at Glass Plant Indicate $26 Million in Potential Savings

    SciTech Connect

    2004-01-01

    In 2000, the Corning glass plant in Greenville, Ohio, consumed almost 114 million kWh of electricity and nearly 308,000 MMBtu of natural gas in its glassmaking processes for a total cost of approximately $6.4 million. A plant-wide assessment indicated that improvement projects could save nearly $26 million and reduce natural gas use by 122,900 MMBtu per year, reduce electrical use by 72,300,000 kWh per year, and reduce CO2 emissions by 180 million pounds per year.

  20. Calibrated energy simulations of potential energy savings in actual retail buildings

    NASA Astrophysics Data System (ADS)

    Alhafi, Zuhaira

    Retail stores are commercial buildings with high energy consumption due to their typically large volumes and long hours of operation. This dissertation assesses heating, ventilating and air conditioning saving strategies based on energy simulations with input parameters from actual retail buildings. The dissertation hypothesis is that "Retail store buildings will save a significant amount of energy by (1) modifying ventilation rates, and/or (2) resetting set point temperatures. These strategies have shown to be beneficial in previous studies. As presented in the literature review, potential energy savings ranged from 0.5% to 30% without compromising indoor thermal comfort and indoor air quality. The retail store buildings can be ventilated at rates significantly lower than rates called for in the ASHRAE Standard 62.1-2010 while maintaining acceptable indoor air quality. Therefore, two dissertation objectives are addressed: (1) Investigate opportunities to reduce ventilation rates that do not compromise indoor air quality in retail stores located in Central Pennsylvania, (2) Investigate opportunities to increase (in summer) and decrease (in winter) set point temperatures that do not compromise thermal comfort. This study conducted experimental measurements of ventilation rates required to maintain acceptable air quality and indoor environmental conditions requirements for two retail stores using ASHRAE Standard 62.1_2012. More specifically, among other parameters, occupancy density, indoor and outdoor pollutant concentrations, and indoor temperatures were measured continuously for one week interval. One of these retail stores were tested four times for a yearlong time period. Pollutants monitored were formaldehyde, carbon dioxide, particle size distributions and concentrations, as well as total volatile organic compounds. As a part of the base protocol, the number of occupants in each store was hourly counted during the test, and the results reveal that the occupant

  1. Application and energy saving potential of superheated steam drying in the food industry

    SciTech Connect

    Fitzpatrick, J.; Robinson, A.

    1996-12-31

    The possibilities of using superheated steam in heat and mass transfer processes such as drying have lately been investigated and tested by several industries. The mode of operation, energy saving potential, advantages of and problems with this media in contact with foodstuffs and food waste sludge are discussed in this article.

  2. Energy aspects and potential energy savings of the new DASI process for milk sterilization

    SciTech Connect

    Frey, B.C.; Stewart, L.E.; Chandarana, D.; Wolfson, R.P.

    1981-01-01

    An experimental study was conducted to determine the difference in total processing energy required by the DASI ultra-high temperature (UHT) system and a conventional high temperature short time (HTST) fluid milk system. Data available in the literature were used to develop an energy use profile for the current US fluid milk system from processor to consumer. The energy data measured and the profile developed were used to estimate the potential energy savings resulting from the introduction of sterile milk in the US fluid milk market. Savings of energy resulting from the introduction of sterile milk were estimated to be 12 million barrels of oil annually.

  3. Energy Savings Potential and Research, Development, & Demonstration Opportunities for Commercial Building Appliances

    SciTech Connect

    Zogg, Robert; Goetzler, William; Ahlfeldt, Christopher; Hiraiwa, Hirokazu; Sathe, Amul; Sutherland, Timothy

    2009-12-01

    This study characterizes and assesses the appliances used in commercial buildings. The primary objectives of this study were to document the energy consumed by commercial appliances and identify research, development and demonstration (RD&D) opportunities for efficiency improvements, excluding product categories such as HVAC, building lighting, refrigeration equipment, and distributed generation systems. The study included equipment descriptions, characteristics of the equipment’s market, national energy consumption, estimates of technical potential for energy-saving technologies, and recommendations for U.S. Department of Energy programs that can promote energy savings in commercial appliances.

  4. The potential savings of using thiazides as the first choice antihypertensive drug: cost-minimisation analysis

    PubMed Central

    Fretheim, Atle; Aaserud, Morten; Oxman, Andrew D

    2003-01-01

    Background All clinical practice guidelines recommend thiazides as a first-choice drug for the management of uncomplicated hypertension. Thiazides are also the lowest priced antihypertensive drugs. Despite this, the use of thiazides is much lower than that of other drug-classes. We wanted to estimate the potential for savings if thiazides were used as the first choice drug for the management of uncomplicated hypertension. Methods For six countries (Canada, France, Germany, Norway, the UK and the US) we estimated the number of people that are being treated for hypertension, and the proportion of them that are suitable candidates for thiazide-therapy. By comparing this estimate with thiazide prescribing, we calculated the number of people that could switch from more expensive medication to thiazides. This enabled us to estimate the potential drug-cost savings. The analysis was based on findings from epidemiological studies and drug trials, and data on sales and prescribing provided by IMS for the year 2000. Results For Canada, France, Germany, Norway, the UK and the US the estimated potential annual savings were US$13.8 million, US$37.4 million, US$72.2 million, US$10.7 million, US$119.7 million and US$433.6 million, respectively. Conclusions Millions of dollars could be saved each year if thiazides were prescribed for hypertension in place of more expensive drugs. Our calculations are based on conservative assumptions. The potential for savings is likely considerably higher and may be more than US$1 billion per year in the US. PMID:12959644

  5. [Research on carbon reduction potential of electric vehicles for low-carbon transportation and its influencing factors].

    PubMed

    Shi, Xiao-Qing; Li, Xiao-Nuo; Yang, Jian-Xin

    2013-01-01

    Transportation is the key industry of urban energy consumption and carbon emissions. The transformation of conventional gasoline vehicles to new energy vehicles is an important initiative to realize the goal of developing low-carbon city through energy saving and emissions reduction, while electric vehicles (EV) will play an important role in this transition due to their advantage in energy saving and lower carbon emissions. After reviewing the existing researches on energy saving and emissions reduction of electric vehicles, this paper analyzed the factors affecting carbon emissions reduction. Combining with electric vehicles promotion program in Beijing, the paper analyzed carbon emissions and reduction potential of electric vehicles in six scenarios using the optimized energy consumption related carbon emissions model from the perspective of fuel life cycle. The scenarios included power energy structure, fuel type (energy consumption per 100 km), car type (CO2 emission factor of fuel), urban traffic conditions (speed), coal-power technologies and battery type (weight, energy efficiency). The results showed that the optimized model was able to estimate carbon emissions caused by fuel consumption more reasonably; electric vehicles had an obvious restrictive carbon reduction potential with the fluctuation of 57%-81.2% in the analysis of six influencing factors, while power energy structure and coal-power technologies play decisive roles in life-cycle carbon emissions of electric vehicles with the reduction potential of 78.1% and 81.2%, respectively. Finally, some optimized measures were proposed to reduce transport energy consumption and carbon emissions during electric vehicles promotion including improving energy structure and coal technology, popularizing energy saving technologies and electric vehicles, accelerating the battery R&D and so on. The research provides scientific basis and methods for the policy development for the transition of new energy vehicles

  6. [Research on carbon reduction potential of electric vehicles for low-carbon transportation and its influencing factors].

    PubMed

    Shi, Xiao-Qing; Li, Xiao-Nuo; Yang, Jian-Xin

    2013-01-01

    Transportation is the key industry of urban energy consumption and carbon emissions. The transformation of conventional gasoline vehicles to new energy vehicles is an important initiative to realize the goal of developing low-carbon city through energy saving and emissions reduction, while electric vehicles (EV) will play an important role in this transition due to their advantage in energy saving and lower carbon emissions. After reviewing the existing researches on energy saving and emissions reduction of electric vehicles, this paper analyzed the factors affecting carbon emissions reduction. Combining with electric vehicles promotion program in Beijing, the paper analyzed carbon emissions and reduction potential of electric vehicles in six scenarios using the optimized energy consumption related carbon emissions model from the perspective of fuel life cycle. The scenarios included power energy structure, fuel type (energy consumption per 100 km), car type (CO2 emission factor of fuel), urban traffic conditions (speed), coal-power technologies and battery type (weight, energy efficiency). The results showed that the optimized model was able to estimate carbon emissions caused by fuel consumption more reasonably; electric vehicles had an obvious restrictive carbon reduction potential with the fluctuation of 57%-81.2% in the analysis of six influencing factors, while power energy structure and coal-power technologies play decisive roles in life-cycle carbon emissions of electric vehicles with the reduction potential of 78.1% and 81.2%, respectively. Finally, some optimized measures were proposed to reduce transport energy consumption and carbon emissions during electric vehicles promotion including improving energy structure and coal technology, popularizing energy saving technologies and electric vehicles, accelerating the battery R&D and so on. The research provides scientific basis and methods for the policy development for the transition of new energy vehicles

  7. Lunar electric fields, surface potential and associated plasma sheaths

    NASA Technical Reports Server (NTRS)

    Freeman, J. W.; Ibrahim, M.

    1975-01-01

    A review is given of studies of the electric-field environment of the moon. Surface electric potentials are reported for the dayside and terminator regions, electron and ion densities in the plasma sheath adjacent to each surface-potential regime are evaluated, and the corresponding Debye lengths are estimated. The electric fields, which are approximated by the surface potential over the Debye length, are shown to be at least three orders of magnitude higher than the pervasive solar-wind electric field and to be confined to within a few tens of meters of the lunar surface.

  8. Energy and emissions saving potential of additive manufacturing: the case of lightweight aircraft components

    SciTech Connect

    Huang, Runze; Riddle, Matthew; Graziano, Diane; Warren, Joshua; Das, Sujit; Nimbalkar, Sachin; Cresko, Joe; Masanet, Eric

    2015-05-08

    Additive manufacturing (AM) holds great potential for improving materials efficiency, reducing life-cycle impacts, and enabling greater engineering functionality compared to conventional manufacturing (CM) processes. For these reasons, AM has been adopted by a growing number of aircraft component manufacturers to achieve more lightweight, cost-effective designs. This study estimates the net changes in life-cycle primary energy and greenhouse gas emissions associated with AM technologies for lightweight metallic aircraft components through the year 2050, to shed light on the environmental benefits of a shift from CM to AM processes in the U.S. aircraft industry. A systems modeling framework is presented, with integrates engineering criteria, life-cycle environmental data, and aircraft fleet stock and fuel use models under different AM adoption scenarios. Estimated fleetwide life-cycle primary energy savings in a rapid adoption scenario reach 70-174 million GJ/year in 2050, with cumulative savings of 1.2-2.8 billion GJ. Associated cumulative emission reduction potentials of CO2e were estimated at 92.8-217.4 million metric tons. About 95% of the savings is attributed to airplane fuel consumption reductions due to lightweighting. In addition, about 4050 tons aluminum, 7600 tons titanium and 8100 tons of nickel alloys could be saved per year in 2050. The results indicate a significant role of AM technologies in helping society meet its long-term energy use and GHG emissions reduction goals, and highlight barriers and opportunities for AM adoption for the aircraft industry.

  9. Potential Energy Savings Due to Phase Change Material in a Building Wall Assembly: An Examination of Two Climates

    SciTech Connect

    Childs, Kenneth W; Stovall, Therese K

    2012-03-01

    Phase change material (PCM), placed in an exterior wall, alters the temperature profile within the wall and thus influences the heat transport through the wall. This may reduce the net energy transport through the wall via interactions with diurnal temperature swings in the external environment or reduce the electricity needed to meet the net load through the wall by shifting the time of the peak load to a time when the cooling system operates more efficiently. This study covers a broad range of parameters that can influence the effectiveness of such a merged thermal storage-thermal insulation system. These parameters included climate, PCM location within the wall, amount of PCM, midpoint of the PCM melting and freezing range relative to the indoor setpoint temperature, temperature range over which phase change occurs, and the wall orientation. Two climates are investigated using finite difference and optimization analyses: Phoenix and Baltimore, with two utility rate schedules. Although potential savings for a PCM with optimized properties were greater when the PCM was concentrated near the inside wall surface, other considerations described here lead to a recommendation for a full-thickness application. An examination of the temperature distribution within the walls also revealed the potential for this system to reduce the amount of energy transported through the wall framing. Finally, economic benefits can exceed energy savings when time-of-day utility rates are in effect, reflecting the value of peak load reductions for the utility grid.

  10. Energy-saving conditions for electric melting of prereduced pellets in the bath of an arc furnace

    NASA Astrophysics Data System (ADS)

    Merker, E. E.; Chermenev, E. A.; Stepanov, V. A.

    2015-06-01

    The problems of increasing the efficiency of electric steelmaking under the application of tubular (hollow) electrodes for supplying iron ore prereduced pellets directly to the high-temperature zone on the surface of a liquid metal are considered. It is shown that the use of an energy-saving regime based on the developed algorithm for the new method of charging pellets makes it possible to decrease the metal losses and to increase the energy efficiency of electric steelmaking.

  11. Potential Savings From Increasing Adherence to Inhaled Corticosteroid Therapy in Medicaid-Enrolled Children

    PubMed Central

    Rust, George; Zhang, Shun; McRoy, Luceta; Pisu, Maria

    2016-01-01

    Background Many asthma-related exacerbations could be prevented by consistent use of daily inhaled corticosteroid therapy (ICS-Rx). Objectives We sought to measure the potential cost savings that could accrue from increasing ICS-Rx adherence in children. Study Design We measured observed costs for a cohort of 43,156 Medicaid-enrolled children in 14 southern states whose initial ICS-Rx was prescribed in 2007. Methods Adherence rates and associated costs were calculated from Medicaid claims. Children were categorized as high or low adherence based on the ratio of ICS-Rx claims filled to total asthma drug claims. Branching tree simulation was used to project the potential cost savings achieved by increasing the proportion of children with ICS-Rx to total asthma Rx ratios greater than 0.5 to 20%, 40%, 60%, 80%, and 100%. Results Increasing the proportion of children who maintain higher adherence after initial ICS-Rx to 40% would generate savings of $95 per child per year. An intervention costing $10 per member per month that resulted in even half of the children maintaining high adherence would generate a 98% return on investment for managed care plans or state Medicaid programs. Net costs decreased incrementally at each level of increase in ICS-Rx adherence. The projected Medicaid cost savings for these 14 states in 2007 ranged from $8.2 million if 40% of the children achieved high adherence, to $57.5 million if 80% achieved high adherence. Conclusions If effective large-scale interventions can be found, there are substantial cost savings to be gained from even modest increases in real-world adherence to ICS-Rx among Medicaid-enrolled children with asthma. PMID:25880622

  12. Electrifying white biotechnology: engineering and economic potential of electricity-driven bio-production.

    PubMed

    Harnisch, Falk; Rosa, Luis F M; Kracke, Frauke; Virdis, Bernardino; Krömer, Jens O

    2015-03-01

    The production of fuels and chemicals by electricity-driven bio-production (i.e., using electric energy to drive biosynthesis) holds great promises. However, this electrification of white biotechnology is particularly challenging to achieve because of the different optimal operating conditions of electrochemical and biochemical reactions. In this article, we address the technical parameters and obstacles to be taken into account when engineering microbial bioelectrochemical systems (BES) for bio-production. In addition, BES-based bio-production processes reported in the literature are compared against industrial needs showing that a still large gap has to be closed. Finally, the feasibility of BES bio-production is analysed based on bulk electricity prices. Using the example of lysine production from sucrose, we demonstrate that there is a realistic market potential as cost savings of 8.4 % (in EU) and 18.0 % (in US) could be anticipated, if the necessary yields can be obtained.

  13. Potential fresh water saving using greywater in toilet flushing in Syria.

    PubMed

    Mourad, Khaldoon A; Berndtsson, Justyna C; Berndtsson, Ronny

    2011-10-01

    Greywater reuse is becoming an increasingly important factor for potable water saving in many countries. Syria is one of the most water scarce countries in the Middle East. However, greywater reuse is still not common in the country. Regulations and standards for greywater reuse are not available. Recently, however, several stakeholders have started to plan for greywater reuse. The main objective of this paper is to evaluate the potential for potable water saving by using greywater for toilet flushing in a typical Syrian city. The Sweida city in the southern part of Syria was chosen for this purpose. Interviews were made in order to reflect the social acceptance, water consumption, and the percentage of different indoor water uses. An artificial wetland (AW) and a commercial bio filter (CBF) were proposed to treat the greywater, and an economic analysis was performed for the treatment system. Results show that using treated greywater for toilet flushing would save about 35% of the drinking water. The economic analyses of the two proposed systems showed that, in the current water tariff, the payback period for AW and CBF in block systems is 7 and 52 years, respectively. However, this period will reduce to 3 and 21 years, respectively, if full water costs are paid by beneficiaries. Hence, introducing artificial wetlands in order to make greywater use efficient appears to be a viable alternative to save potable water.

  14. The energy saving potential of precooling incoming outdoor air by indirect evaporative cooling

    SciTech Connect

    Chen, P.; Qin, H.; Huang, Y.J.; Wu, H.; Blumstein, C.

    1992-09-01

    This paper investigates the energy saving potentials of using indirect evaporative coolers to precool incoming outdoor air as the first stage of a standard cooling system. For dry and moderately humid locations, either exhaust room air or outdoor air can be used as the secondary air to the indirect evaporative precooler with similar energy savings. Under these conditions, the use of outdoor air is recommended due to the simplicity in installing the duct system. For humid locations, the use of exhaust room air is recommended because the precooling capacity and energy savings will be greatly increased. For locations with short cooling seasons, the use of indirect evaporative coolers for precooling may not be worthwhile. The paper also gives some simplified indices for easily predicting the precooling capacity, energy savings and water consumption of an indirect evaporative precooler. These indices can be used for cooling systems with continuous operation, but further work is needed to determine whether the same indices are also suitable for cooling systems with intermittent operations.

  15. The Oklahoma Field Test: Air-Conditioning Electricity Savings from Standard Energy Conservation Measures, Radiant Barriers, and High-Efficiency Window Air Conditioners

    SciTech Connect

    Ternes, M.P.

    1992-01-01

    general replacement of low-efficiency air conditioners (replacing units in all houses without considering pre-weatherization air-conditioning electricity consumption) was not cost effective in the test houses. ECMs installed under the Oklahoma WAP and installed in combination with an attic radiant barrier did not produce air-conditioning electricity savings that could be measured in the field test. The following conclusions were drawn from the study: (1) programs directed at reducing air-conditioning electricity consumption should be targeted at clients with high consumption to improve cost effectiveness; (2) replacing low-efficiency air conditioners with high-efficiency units should be considered an option in a weatherization program directed at reducing air-conditioning electricity consumption; (3) ECMs currently being installed under the Oklahoma WAP (chosen based on effectiveness at reducing space-heating energy consumption) should continue to be justified based on their space-heating energy savings potential only; and (4) attic radiant barriers should not be included in the Oklahoma WAP if alternatives with verified savings are available or until further testing demonstrates energy savings or other benefits in this type of housing.

  16. Alcoa World Alumina: Plant-Wide Assessment at Arkansas Operations Reveals More than$900,000 in Potential Annual Savings

    SciTech Connect

    Not Available

    2003-07-01

    The plant-wide energy-efficiency assessment performed in 2001 at the Alcoa World Alumina Arkansas Operations in Bauxite, Arkansas, identified seven opportunities to save energy and reduce costs. By implementing five of these improvements, the facility can save 15,100 million British thermal units per year in natural gas and 8.76 million kilowatt-hours per year in electricity. This translates into approximate annual savings of$925,300 in direct energy costs and non-fuel operating and maintenance costs. The required capital investment is estimated at$271,200. The average payback period for all five projects would be approximately 8 months.

  17. Understanding the electrical behavior of the action potential in terms of elementary electrical sources.

    PubMed

    Rodriguez-Falces, Javier

    2015-03-01

    A concept of major importance in human electrophysiology studies is the process by which activation of an excitable cell results in a rapid rise and fall of the electrical membrane potential, the so-called action potential. Hodgkin and Huxley proposed a model to explain the ionic mechanisms underlying the formation of action potentials. However, this model is unsuitably complex for teaching purposes. In addition, the Hodgkin and Huxley approach describes the shape of the action potential only in terms of ionic currents, i.e., it is unable to explain the electrical significance of the action potential or describe the electrical field arising from this source using basic concepts of electromagnetic theory. The goal of the present report was to propose a new model to describe the electrical behaviour of the action potential in terms of elementary electrical sources (in particular, dipoles). The efficacy of this model was tested through a closed-book written exam. The proposed model increased the ability of students to appreciate the distributed character of the action potential and also to recognize that this source spreads out along the fiber as function of space. In addition, the new approach allowed students to realize that the amplitude and sign of the extracellular electrical potential arising from the action potential are determined by the spatial derivative of this intracellular source. The proposed model, which incorporates intuitive graphical representations, has improved students' understanding of the electrical potentials generated by bioelectrical sources and has heightened their interest in bioelectricity.

  18. Preliminary Study of the Fuel Saving Potential of Regenerative Turbofans for Commercial Subsonic Transports. [engine tests

    NASA Technical Reports Server (NTRS)

    Kraft, G. A.

    1975-01-01

    The fuel savings potential of regenerative turbofans was calculated and compared with that of a reference turbofan. At the design altitude of 10.67 km and Mach 0.80, the turbine-inlet-temperature of the regenerative turbofan was fixed at 1700 K while the overall pressure ratio was varied from 10 to 20. The fan pressure ratio was fixed at 1.6 and the bypass ratio varied from 8 to 10. The heat exchanger design parameters such as pressure drop and effectiveness varied from 4 to 8 percent and from 0.80 to 0.90, respectively. Results indicate a fuel savings due to regeneration of 4.1 percent and no change in takeoff gross weight.

  19. Pittsburgh as a High Risk Population: The Potential Savings of a Personalized Dental Care Plan.

    PubMed

    Ng, Andrew J; Vieira, Alexandre R

    2016-01-01

    Objectives. Little evidence exists for the current standard of two annual preventative care visits. The purpose of this study was investigate this claim by modeling the potential savings of implementing a personalized care plan for high risk individuals in the Pittsburgh region. Methods. Using radiographs from 39 patients in the University of Pittsburgh Dental Registry and DNA Repository database, two models were created to analyse the direct savings of implementing a more aggressive preventative treatment plan and to view the longitudinal cost of increased annual yearly visits. Results. There is a significant decrease (p < 0.001) between original and modeled treatment cost when treatment severity is reduced. In addition, there is a significant decrease in adult lifetime treatment cost (p < 0.001) for up to four annual visits. Conclusions. Patients in high risk populations may see significant cost benefits in treatment cost when a personalized care plan, or higher annual preventative care visits, is implemented. PMID:27006657

  20. ENCOURAGING ELECTRICITY SAVINGS IN A UNIVERSITY RESIDENTIAL HALL THROUGH A COMBINATION OF FEEDBACK, VISUAL PROMPTS, AND INCENTIVES

    PubMed Central

    Bekker, Marthinus J; Cumming, Tania D; Osborne, Nikola K.P; Bruining, Angela M; McClean, Julia I; Leland, Louis S

    2010-01-01

    This experiment investigated the combined use of visual prompts, daily feedback, and rewards to reduce electricity consumption in a university residential hall. After a 17-day baseline period, the experimental intervention was introduced in the intervention hall, and no change was made in the control hall. Energy usage decreased in the intervention hall, but energy usage did not change appreciably in the control hall. In the intervention hall, mean daytime and nighttime savings were 16.2% and 10.7%, respectively, compared to savings of 3.8% (day) and 6.5% (night) in the control hall. PMID:21119909

  1. Encouraging electricity savings in a university residential hall through a combination of feedback, visual prompts, and incentives.

    PubMed

    Bekker, Marthinus J; Cumming, Tania D; Osborne, Nikola K P; Bruining, Angela M; McClean, Julia I; Leland, Louis S

    2010-01-01

    This experiment investigated the combined use of visual prompts, daily feedback, and rewards to reduce electricity consumption in a university residential hall. After a 17-day baseline period, the experimental intervention was introduced in the intervention hall, and no change was made in the control hall. Energy usage decreased in the intervention hall, but energy usage did not change appreciably in the control hall. In the intervention hall, mean daytime and nighttime savings were 16.2% and 10.7%, respectively, compared to savings of 3.8% (day) and 6.5% (night) in the control hall.

  2. Energy and emissions saving potential of additive manufacturing: the case of lightweight aircraft components

    DOE PAGES

    Huang, Runze; Riddle, Matthew; Graziano, Diane; Warren, Joshua; Das, Sujit; Nimbalkar, Sachin; Cresko, Joe; Masanet, Eric

    2015-05-08

    Additive manufacturing (AM) holds great potential for improving materials efficiency, reducing life-cycle impacts, and enabling greater engineering functionality compared to conventional manufacturing (CM) processes. For these reasons, AM has been adopted by a growing number of aircraft component manufacturers to achieve more lightweight, cost-effective designs. This study estimates the net changes in life-cycle primary energy and greenhouse gas emissions associated with AM technologies for lightweight metallic aircraft components through the year 2050, to shed light on the environmental benefits of a shift from CM to AM processes in the U.S. aircraft industry. A systems modeling framework is presented, with integratesmore » engineering criteria, life-cycle environmental data, and aircraft fleet stock and fuel use models under different AM adoption scenarios. Estimated fleetwide life-cycle primary energy savings in a rapid adoption scenario reach 70-174 million GJ/year in 2050, with cumulative savings of 1.2-2.8 billion GJ. Associated cumulative emission reduction potentials of CO2e were estimated at 92.8-217.4 million metric tons. About 95% of the savings is attributed to airplane fuel consumption reductions due to lightweighting. In addition, about 4050 tons aluminum, 7600 tons titanium and 8100 tons of nickel alloys could be saved per year in 2050. The results indicate a significant role of AM technologies in helping society meet its long-term energy use and GHG emissions reduction goals, and highlight barriers and opportunities for AM adoption for the aircraft industry.« less

  3. The potential for electricity efficiency improvements in the US Residential Sector

    SciTech Connect

    Koomey, J.G.; Atkinson, C.; Meier, A.; McMahon, J.E.; Boghosian, S.; Atkinson, B.; Turiel, I.; Levine, M.D.; Nordman, B.; Chan, P.

    1991-07-01

    This study represents the most elaborate assessment to date of US residential sector electricity improvements. Previous analyses have estimated the conservation potential for other countries, states, or individual utility service territories. As concern over greenhouse gas emissions has increased, interest has grown in estimates of conservation potential for the US residential sector as a whole. The earliest detailed estimate of US conservation potential is now out of date, while more recent estimates are less detailed than is desirable for engineering-economic estimates of the costs of reducing carbon emissions. In this paper, we first describe the methodology for creating supply curves of conserved energy, and then illustrate the subtleties of assessing the technical conservation potential. Next we present the data and forecasts used in this assessment, including costs, baseline thermal characteristics, energy use, and energy savings. Finally, we present the main results and conclusions from the analysis, and discuss future work. 102 refs., 7 figs., 16 tabs.

  4. Central role of the observable electric potential in transport equations.

    PubMed

    Garrido, J; Compañ, V; López, M L

    2001-07-01

    Nonequilibrium systems are usually studied in the framework of transport equations that involve the true electric potential (TEP), a nonobservable variable. Nevertheless another electric potential, the observable electric potential (OEP), may be defined to construct a useful set of transport equations. In this paper several basic characteristics of the OEP are deduced and emphasized: (i) the OEP distribution depends on thermodynamic state of the solution, (ii) the observable equations have a reference value for all other transport equations, (iii) the bridge that connects the OEP with a certain TEP is usually defined by the ion activity coefficient, (iv) the electric charge density is a nonobservable variable, and (v) the OEP formulation constitutes a natural model for studying the fluxes in membrane systems. PMID:11461346

  5. Central role of the observable electric potential in transport equations.

    PubMed

    Garrido, J; Compañ, V; López, M L

    2001-07-01

    Nonequilibrium systems are usually studied in the framework of transport equations that involve the true electric potential (TEP), a nonobservable variable. Nevertheless another electric potential, the observable electric potential (OEP), may be defined to construct a useful set of transport equations. In this paper several basic characteristics of the OEP are deduced and emphasized: (i) the OEP distribution depends on thermodynamic state of the solution, (ii) the observable equations have a reference value for all other transport equations, (iii) the bridge that connects the OEP with a certain TEP is usually defined by the ion activity coefficient, (iv) the electric charge density is a nonobservable variable, and (v) the OEP formulation constitutes a natural model for studying the fluxes in membrane systems.

  6. Part-load performance characterization and energy savings potential of the RTU challenge unit: Carrier weather expert

    SciTech Connect

    Wang, Weimin; Katipamula, Srinivas; Taasevigen, Danny J.

    2015-09-29

    This report documents the development of part-load performance curves and there use with the EnergyPlus simulation tool to estimate the potential savings from the use of WeatherExpert units compared to other standard options.

  7. Life-cycle energy savings potential from aluminum-intensive vehicles

    SciTech Connect

    Stodolsky, F.; Vyas, A.; Cuenca, R.; Gaines, L.

    1995-07-01

    The life-cycle energy and fuel-use impacts of US-produced aluminum-intensive passenger cars and passenger trucks are assessed. The energy analysis includes vehicle fuel consumption, material production energy, and recycling energy. A model that stimulates market dynamics was used to project aluminum-intensive vehicle market shares and national energy savings potential for the period between 2005 and 2030. We conclude that there is a net energy savings with the use of aluminum-intensive vehicles. Manufacturing costs must be reduced to achieve significant market penetration of aluminum-intensive vehicles. The petroleum energy saved from improved fuel efficiency offsets the additional energy needed to manufacture aluminum compared to steel. The energy needed to make aluminum can be reduced further if wrought aluminum is recycled back to wrought aluminum. We find that oil use is displaced by additional use of natural gas and nonfossil energy, but use of coal is lower. Many of the results are not necessarily applicable to vehicles built outside of the United States, but others could be used with caution.

  8. Part-Load Performance Characterization and Energy Savings Potential of the RTU Challenge Unit: Daikin Rebel

    SciTech Connect

    Wang, Weimin; Katipamula, Srinivas

    2013-09-30

    In 2011, the U.S. Department of Energy’s Building Technology Office (DOE’s BTO), with help from the Better Buildings Alliance (BBA) members, developed a specification for high performance rooftop air-conditioning units (RTU Challenge) with capacity ranges between 10 and 20 tons (DOE 2013). Daikin’s Rebel for the first rooftop unit system that was recognized by DOE in May 2012 as meeting the RTU Challenge specifications. This report documents the development of part-load performance curves and its use with EnergyPlus simulation tool to estimate the potential savings from use of Rebel compared to other standard options.

  9. Residential energy use in Mexico: Structure, evolution, environmental impacts, and savings potential

    SciTech Connect

    Masera, O.; Friedmann, R.; deBuen, O.

    1993-05-01

    This article examines the characteristics of residential energy use in Mexico, its environmental impacts, and the savings potential of the major end-uses. The main options and barriers to increase the efficiency of energy use are discussed. The energy analysis is based on a disaggregation of residential energy use by end-uses. The dynamics of the evolution of the residential energy sector during the past 20 years are also addressed when the information is available. Major areas for research and for innovative decision-making are identified and prioritized.

  10. Understanding the Electrical Behavior of the Action Potential in Terms of Elementary Electrical Sources

    ERIC Educational Resources Information Center

    Rodriguez-Falces, Javier

    2015-01-01

    A concept of major importance in human electrophysiology studies is the process by which activation of an excitable cell results in a rapid rise and fall of the electrical membrane potential, the so-called action potential. Hodgkin and Huxley proposed a model to explain the ionic mechanisms underlying the formation of action potentials. However,…

  11. Potential-step amplified nonequilibrium thermal-electric converters

    NASA Astrophysics Data System (ADS)

    Chen, Gang

    2005-04-01

    We predict a large thermoelectric effect at properly designed electrical potential steps that can be exploited to design thermoelectric coolers and power generators. A large nonequilibrium between electrons and phonons can be created at a potential step either by a heat flux (for power generation) or an electrical current. This effect can only exist in a forward structural configuration, which consists of a short region with low doping and a long region with high doping, and a potential step from the short to the long region. Electron temperature discontinuity is amplified at such an interface, leading to a large Seebeck voltage drop at the interface. A similar effect does not exist in a reverse structure. Modeling shows that higher thermal-electric power generation and cooling efficiency can be realized using the effect.

  12. Estimating the maximum potential revenue for grid connected electricity storage :

    SciTech Connect

    Byrne, Raymond Harry; Silva Monroy, Cesar Augusto.

    2012-12-01

    The valuation of an electricity storage device is based on the expected future cash flow generated by the device. Two potential sources of income for an electricity storage system are energy arbitrage and participation in the frequency regulation market. Energy arbitrage refers to purchasing (stor- ing) energy when electricity prices are low, and selling (discharging) energy when electricity prices are high. Frequency regulation is an ancillary service geared towards maintaining system frequency, and is typically procured by the independent system operator in some type of market. This paper outlines the calculations required to estimate the maximum potential revenue from participating in these two activities. First, a mathematical model is presented for the state of charge as a function of the storage device parameters and the quantities of electricity purchased/sold as well as the quantities o ered into the regulation market. Using this mathematical model, we present a linear programming optimization approach to calculating the maximum potential revenue from an elec- tricity storage device. The calculation of the maximum potential revenue is critical in developing an upper bound on the value of storage, as a benchmark for evaluating potential trading strate- gies, and a tool for capital nance risk assessment. Then, we use historical California Independent System Operator (CAISO) data from 2010-2011 to evaluate the maximum potential revenue from the Tehachapi wind energy storage project, an American Recovery and Reinvestment Act of 2009 (ARRA) energy storage demonstration project. We investigate the maximum potential revenue from two di erent scenarios: arbitrage only and arbitrage combined with the regulation market. Our analysis shows that participation in the regulation market produces four times the revenue compared to arbitrage in the CAISO market using 2010 and 2011 data. Then we evaluate several trading strategies to illustrate how they compare to the

  13. Remanufacturing and energy savings.

    PubMed

    Gutowski, Timothy G; Sahni, Sahil; Boustani, Avid; Graves, Stephen C

    2011-05-15

    Remanufactured products that can substitute for new products are generally claimed to save energy. These claims are made from studies that look mainly at the differences in materials production and manufacturing. However, when the use phase is included, the situation can change radically. In this Article, 25 case studies for eight different product categories were studied, including: (1) furniture, (2) clothing, (3) computers, (4) electric motors, (5) tires, (6) appliances, (7) engines, and (8) toner cartridges. For most of these products, the use phase energy dominates that for materials production and manufacturing combined. As a result, small changes in use phase efficiency can overwhelm the claimed savings from materials production and manufacturing. These use phase energy changes are primarily due to efficiency improvements in new products, and efficiency degradation in remanufactured products. For those products with no, or an unchanging, use phase energy requirement, remanufacturing can save energy. For the 25 cases, we found that 8 cases clearly saved energy, 6 did not, and 11 were too close to call. In some cases, we could examine how the energy savings potential of remanufacturing has changed over time. Specifically, during times of significant improvements in energy efficiency, remanufacturing would often not save energy. A general design trend seems to be to add power to a previously unpowered product, and then to improve on the energy efficiency of the product over time. These trends tend to undermine the energy savings potential of remanufacturing.

  14. Potential cost savings from discharge allowance trading: A case study and implications for water quality trading

    NASA Astrophysics Data System (ADS)

    Sado, Yukako; Boisvert, Richard N.; Poe, Gregory L.

    2010-02-01

    Applying a trading ratio system similar to that proposed by Hung and Shaw (2005), we estimate the potential cost savings of a phosphorus emissions trading program that meets overall total maximum daily load allocations among 22 wastewater treatment plants (WWTPs) in the Passaic River watershed (United States) to be a modest 2-3% relative to a no-trade baseline. These results may be typical of those in relatively small watersheds such as the Passaic, where there are limited numbers of potential traders and relatively homogeneous abatement technologies across WWTPs. More substantial gains from trade may accrue to a concentrated group of WWTPs, suggesting that watershed managers should focus on a targeted set of traders within a watershed. Under certain conditions, additional gains may be achieved by aggregating WWTPs into zones within which there can be one-to-one allowance trading.

  15. A Perinatal Care Quality and Safety Initiative: Hospital Costs and Potential Savings

    PubMed Central

    Kozhimannil, Katy B.; Sommerness, Samantha; Rauk, Phillip; Gams, Rebecca; Hirt, Charles; Davis, Stanley; Miller, Kristi K.; Landers, Daniel V.

    2013-01-01

    Background There is increasing national focus on hospital initiatives to improve obstetric and neonatal outcomes. While costs of providing care may decrease with improved quality, the accompanying reduced adverse outcomes may impact hospital revenues. The purpose of this study was to estimate, from a hospital perspective, the financial impacts of implementing a perinatal quality and safety initiative. Methods In 2008, a Minnesota-based health system (Fairview Health Services) launched the Zero Birth Injury (ZBI) initiative, which uses evidence-based care bundles to guide management of obstetric services. We conducted a pre-post analysis of financial impacts of ZBI, using hospital administrative records to measure costs and revenues associated with changes in maternal and neonatal birth injuries before (2008) and after (2009–11) the initiative. Results After adjusting for relevant covariates, implementation of ZBI was associated with an 11% decrease in the rate of maternal and neonatal adverse outcomes between 2008 and 2011 (AOR=0.89, p=0.076). As a result of the adverse events avoided, the hospital system saved $284,985 in costs but earned $324,333 less revenue, which produced a net financial decrease of $39,348 (or a $305 net financial loss per adverse event avoided) in 2011, compared with 2008. Conclusions Adoption of a perinatal quality and safety initiative that reduced birth injuries had little net financial impact on the hospital. ZBI produced better clinical results at a lower cost, which represents potential savings for payers, but the hospital system offering increased quality reaped no clear financial rewards. These results highlight the important role for shared-savings collaborations (among patients, providers, government and third-party payers, and employers) to incentivize quality improvement. Widespread adoption of perinatal safety initiatives combined with innovative payment models may contribute to better health at reduced cost. PMID:23991507

  16. The energy-savings potential of electrochromic windows in the UScommercial buildings sector

    SciTech Connect

    Lee, Eleanor; Yazdanian, Mehry; Selkowitz, Stephen

    2004-04-30

    Switchable electrochromic (EC) windows have been projected to significantly reduce the energy use of buildings nationwide. This study quantifies the potential impact of electrochromic windows on US primary energy use in the commercial building sector and also provides a broader database of energy use and peak demand savings for perimeter zones than that given in previous LBNL simulation studies. The DOE-2.1E building simulation program was used to predict the annual energy use of a three-story prototypical commercial office building located in five US climates and 16 California climate zones. The energy performance of an electrochromic window controlled to maintain daylight illuminance at a prescribed setpoint level is compared to conventional and the best available commercial windows as well as windows defined by the ASHRAE 90.1-1999 and California Title 24-2005 Prescriptive Standards. Perimeter zone energy use and peak demand savings data by orientation, window size, and climate are given for windows with interior shading, attached shading, and horizon obstructions (to simulate an urban environment). Perimeter zone primary energy use is reduced by 10-20% in east, south, and west zones in most climates if the commercial building has a large window-to-wall area ratio of 0.60 compared to a spectrally selective low-e window with daylighting controls and no interior or exterior shading. Peak demand for the same condition is reduced by 20-30%. The emerging electrochromic window with daylighting controls is projected to save approximately 91.5-97.3 10{sup 12} Btu in the year 2030 compared to a spectrally selective low-E window with manually-controlled interior shades and no daylighting controls if it reaches a 40% market penetration level in that year.

  17. Electric Current Analysis of CFRP using Perfect Fluid Potential Flow

    NASA Astrophysics Data System (ADS)

    Todoroki, Akira

    A new analytical method to calculate the electric current density between two probes in carbon-fiber-reinforced plastic (CFRP) is presented. Unidirectional CFRP has strongly orthotropic electric conductance. Even when electric current is applied to a CFRP plate using two probes on a single surface, the electric current density is not uniform along the cross-section. The electric current is concentrated near the surface where an electric current is applied. Although it is important to know the electric current density in the CFRP plate for the analysis of lightning effects, the density is difficult to calculate using a three-dimensional finite element model. In the present study, the orthotropic coordinate is transformed into a uniform coordinate. Laplace’s equation is solved using the potential theory for a perfect fluid. Equations solved employing an infinite-body approximation are verified with a finite element model. As a result, the new analysis method is demonstrated to be efficient for unidirectional CFRP. The limitations of the method are also discussed.

  18. Energy Savings Potential of Flexible and Adaptive HVAC Distribution Systems for Office Buildings

    SciTech Connect

    Loftness, Vivian; Brahme, Rohini; Mondazzi, Michelle; Vineyard, Edward; MacDonald, Michael

    2002-06-01

    It has been understood by architects and engineers that office buildings with easily re-configurable space and flexible mechanical and electrical systems are able to provide comfort that increases worker productivity while using less energy. Raised floors are an example of how fresh air, thermal conditioning, lighting needs, and network access can be delivered in a flexible manner that is not ''embedded'' within the structure. What are not yet documented is how well these systems perform and how much energy they can save. This area is being investigated in phased projects of the 21st Century Research Program of the Air-conditioning and Refrigeration Technology Institute. For the initial project, research teams at the Center for Building Performance and Diagnostics, Pittsburgh, Pennsylvania, and Oak Ridge National Laboratory, Oak Ridge, Tennessee, documented the diversity, performance, and incidence of flexible and adaptive HVAC systems. Information was gathered worldwide from journal and conference articles, case studies, manufactured products and assemblies, and interviews with design professionals. Their report thoroughly describes the variety of system types along with the various design alternatives observed for plenums, diffusers, individual control, and system integration. Many of the systems are illustrated in the report and the authors provide quantitative and qualitative comparisons. Among conclusions regarding key design issues, and barriers to widespread adoption, the authors state that flexible and adaptive HVAC systems, such as underfloor air, perform as well if not better than ceiling-based systems. Leading engineers have become active proponents after their first experience, which is resulting in these flexible and adaptive HVAC systems approaching 10 percent of the new construction market. To encourage adoption of this technology that improves thermal comfort and indoor air quality, follow-on work is required to further document performance

  19. Energy Saving Potentials and Air Quality Benefits of Urban Heat Island Mitigation

    SciTech Connect

    Akbari, Hashem

    2005-08-23

    Urban areas tend to have higher air temperatures than their rural surroundings as a result of gradual surface modifications that include replacing the natural vegetation with buildings and roads. The term ''Urban Heat Island'' describes this phenomenon. The surfaces of buildings and pavements absorb solar radiation and become extremely hot, which in turn warm the surrounding air. Cities that have been ''paved over'' do not receive the benefit of the natural cooling effect of vegetation. As the air temperature rises, so does the demand for air-conditioning (a/c). This leads to higher emissions from power plants, as well as increased smog formation as a result of warmer temperatures. In the United States, we have found that this increase in air temperature is responsible for 5-10% of urban peak electric demand for a/c use, and as much as 20% of population-weighted smog concentrations in urban areas. Simple ways to cool the cities are the use of reflective surfaces (rooftops and pavements) and planting of urban vegetation. On a large scale, the evapotranspiration from vegetation and increased reflection of incoming solar radiation by reflective surfaces will cool a community a few degrees in the summer. As an example, computer simulations for Los Angeles, CA show that resurfacing about two-third of the pavements and rooftops with reflective surfaces and planting three trees per house can cool down LA by an average of 2-3K. This reduction in air temperature will reduce urban smog exposure in the LA basin by roughly the same amount as removing the basin entire onroad vehicle exhaust. Heat island mitigation is an effective air pollution control strategy, more than paying for itself in cooling energy cost savings. We estimate that the cooling energy savings in U.S. from cool surfaces and shade trees, when fully implemented, is about $5 billion per year (about $100 per air-conditioned house).

  20. Electric fields and electrostatic potentials in the high latitude ionosphere

    NASA Technical Reports Server (NTRS)

    Banks, P. M.; Saint Maurice, J.-P.; Heelis, R. A.; Hanson, W. B.

    1981-01-01

    Recent interpretive studies of electric field-driven ionospheric plasma convection data from the AE-C satellite are described, where the instruments employed include an ion drift meter and an ion-retarding potential analyzer. Electrostatic potential curves are derived from ion drift velocity measurements for high-latitude segments of the satellite's orbit. The potential curves are shown to be useful in determining the character of the global electrostatic potential pattern, with emphasis on the separation of convective cells. Results are given for six orbits, with attention to the mid-day auroral region.

  1. Turkey's High Temperature Geothermal Energy Resources and Electricity Production Potential

    NASA Astrophysics Data System (ADS)

    Bilgin, Ö.

    2012-04-01

    Turkey is in the first 7 countries in the world in terms of potential and applications. Geothermal energy which is an alternative energy resource has advantages such as low-cost, clean, safe and natural resource. Geothermal energy is defined as hot water and steam which is formed by heat that accumulated in various depths of the Earth's crust; with more than 20oC temperature and which contain more than fused minerals, various salts and gases than normal underground and ground water. It is divided into three groups as low, medium and high temperature. High-temperature fluid is used in electricity generation, low and medium temperature fluids are used in greenhouses, houses, airport runways, animal farms and places such as swimming pools heating. In this study high temperature geothermal fields in Turkey which is suitable for electricity production, properties and electricity production potential was investigated.

  2. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  3. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  4. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  5. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  6. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  7. Computational Method for Electrical Potential and Other Field Problems

    ERIC Educational Resources Information Center

    Hastings, David A.

    1975-01-01

    Proposes the finite differences relaxation method as a teaching tool in secondary and university level courses discussing electrical potential, temperature distribution in a region, and similar problems. Outlines the theory and operating procedures of the method, and discusses examples of teaching applications, including possible laboratory…

  8. Reduction of coherence of the human brain electric potentials

    NASA Astrophysics Data System (ADS)

    Novik, Oleg; Smirnov, Fedor

    Plenty of technological processes are known to be damaged by magnetic storms. But technology is controlled by men and their functional systems may be damaged as well. We are going to consider the electro-neurophysiological aspect of the general problem: men surrounded by physical fields including ones of cosmic origination. Magnetic storms’ influence had been observed for a group of 13 students (practically healthy girls and boys from 18 to 23 years old, Moscow). To control the main functional systems of the examinees, their electroencephalograms (EEG) were being registered along with electrocardiograms, respiratory rhythms, arterial blood pressure and other characteristics during a year. All of these characteristics, save for the EEG, were within the normal range for all of the examinees during measurements. According to the EEG investigations by implementation of the computer proof-reading test in absence of magnetic storms, the values of the coherence function of time series of the theta-rhythm oscillations (f = 4 - 7.9 Hz, A = 20 μV) of electric potentials of the frontal-polar and occipital areas of the head belong to the interval [0.3, 0.8] for all of the students under investigation. (As the proof-reading test, it was necessary to choose given symbols from a random sequence of ones demonstrated at a monitor and to enter the number of the symbols discovered in a computer. Everyone was known that the time for determination of symbols is unlimited. On the other hand, nobody was known that the EEG and other registrations mentioned are connected with electromagnetic geophysical researches and geomagnetic storms). Let us formulate the main result: by implementation of the same test during a magnetic storm, 5 ≤ K ≤ 6, or no later then 24 hours after its beginning (different types of moderate magnetic storms occurred, the data of IZMIRAN were used), the values of the theta-rhythm frontal - occipital coherence function of all of the students of the group under

  9. Energy Savings Potential and RD&D Opportunities for Non-Vapor-Compression HVAC Technologies

    SciTech Connect

    none,

    2014-03-01

    While vapor-compression technologies have served heating, ventilation, and air-conditioning (HVAC) needs very effectively, and have been the dominant HVAC technology for close to 100 years, the conventional refrigerants used in vapor-compression equipment contribute to global climate change when released to the atmosphere. This Building Technologies Office report: --Identifies alternatives to vapor-compression technology in residential and commercial HVAC applications --Characterizes these technologies based on their technical energy savings potential, development status, non-energy benefits, and other factors affecting end-user acceptance and their ability to compete with conventional vapor-compression systems --Makes specific research, development, and deployment (RD&D) recommendations to support further development of these technologies, should DOE choose to support non-vapor-compression technology further.

  10. Web-based Tool Identifies and Quantifies Potential Cost Savings Measures at the Hanford Site

    SciTech Connect

    Renevitz, Marisa J.; Peschong, Jon C.; Charboneau, Briant L.; Simpson, Brett C.

    2014-01-09

    The Technical Improvement system is an approachable web-based tool that is available to Hanford DOE staff, site contractors, and general support service contractors as part of the baseline optimization effort underway at the Hanford Site. Finding and implementing technical improvements are a large part of DOE’s cost savings efforts. The Technical Improvement dashboard is a key tool for brainstorming and monitoring the progress of submitted baseline optimization and potential cost/schedule efficiencies. The dashboard is accessible to users over the Hanford Local Area Network (HLAN) and provides a highly visual and straightforward status to management on the ideas provided, alleviating the need for resource intensive weekly and monthly reviews.

  11. Electric potential calculation in molecular simulation of electric double layer capacitors

    NASA Astrophysics Data System (ADS)

    Wang, Zhenxing; Olmsted, David L.; Asta, Mark; Laird, Brian B.

    2016-11-01

    For the molecular simulation of electric double layer capacitors (EDLCs), a number of methods have been proposed and implemented to determine the one-dimensional electric potential profile between the two electrodes at a fixed potential difference. In this work, we compare several of these methods for a model LiClO4-acetonitrile/graphite EDLC simulated using both the traditional fixed-charged method (FCM), in which a fixed charge is assigned a priori to the electrode atoms, or the recently developed constant potential method (CPM) (2007 J. Chem. Phys. 126 084704), where the electrode charges are allowed to fluctuate to keep the potential fixed. Based on an analysis of the full three-dimensional electric potential field, we suggest a method for determining the averaged one-dimensional electric potential profile that can be applied to both the FCM and CPM simulations. Compared to traditional methods based on numerically solving the one-dimensional Poisson’s equation, this method yields better accuracy and no supplemental assumptions.

  12. Electric potential calculation in molecular simulation of electric double layer capacitors.

    PubMed

    Wang, Zhenxing; Olmsted, David L; Asta, Mark; Laird, Brian B

    2016-11-23

    For the molecular simulation of electric double layer capacitors (EDLCs), a number of methods have been proposed and implemented to determine the one-dimensional electric potential profile between the two electrodes at a fixed potential difference. In this work, we compare several of these methods for a model LiClO4-acetonitrile/graphite EDLC simulated using both the traditional fixed-charged method (FCM), in which a fixed charge is assigned a priori to the electrode atoms, or the recently developed constant potential method (CPM) (2007 J. Chem. Phys. 126 084704), where the electrode charges are allowed to fluctuate to keep the potential fixed. Based on an analysis of the full three-dimensional electric potential field, we suggest a method for determining the averaged one-dimensional electric potential profile that can be applied to both the FCM and CPM simulations. Compared to traditional methods based on numerically solving the one-dimensional Poisson's equation, this method yields better accuracy and no supplemental assumptions.

  13. Electric potential calculation in molecular simulation of electric double layer capacitors.

    PubMed

    Wang, Zhenxing; Olmsted, David L; Asta, Mark; Laird, Brian B

    2016-11-23

    For the molecular simulation of electric double layer capacitors (EDLCs), a number of methods have been proposed and implemented to determine the one-dimensional electric potential profile between the two electrodes at a fixed potential difference. In this work, we compare several of these methods for a model LiClO4-acetonitrile/graphite EDLC simulated using both the traditional fixed-charged method (FCM), in which a fixed charge is assigned a priori to the electrode atoms, or the recently developed constant potential method (CPM) (2007 J. Chem. Phys. 126 084704), where the electrode charges are allowed to fluctuate to keep the potential fixed. Based on an analysis of the full three-dimensional electric potential field, we suggest a method for determining the averaged one-dimensional electric potential profile that can be applied to both the FCM and CPM simulations. Compared to traditional methods based on numerically solving the one-dimensional Poisson's equation, this method yields better accuracy and no supplemental assumptions. PMID:27624573

  14. Small solar thermal electric power plants with early commercial potential

    NASA Technical Reports Server (NTRS)

    Jones, H. E.; Bisantz, D. J.; Clayton, R. N.; Heiges, H. H.; Ku, A. C.

    1979-01-01

    Cost-effective small solar thermal electric power plants (1- to 10-MW nominal size) offer an attractive way of helping the world meet its future energy needs. The paper describes the characteristics of a conceptual near-term plant (about 1 MW) and a potential 1990 commercial version. The basic system concept is one in which steam is generated using two-axis tracking, parabolic dish, and point-focusing collectors. The steam is transported through low-loss piping to a central steam turbine generator unit where it is converted to electricity. The plants have no energy storage and their output power level varies with the solar insolation level. This system concept, which is firmly based on state-of-the-art technology, is projected to offer one of the fastest paths for U.S. commercialization of solar thermal electric power plants through moderate technology advances and mass production.

  15. Harnessing Potential Evaporation as a Renewable Energy Resource With Water-Saving Benefits

    NASA Astrophysics Data System (ADS)

    Cavusoglu, A. H.; Chen, X.; Gentine, P.; Sahin, O.

    2015-12-01

    Water's large latent heat of vaporization makes evaporation a critical component of the energy balance at the Earth's surface. An immense amount of energy drives the hydrological cycle and is an important component of various weather and climate patterns. However, the potential of harnessing evaporation has received little attention as a renewable energy resource compared to wind and solar energy. Here, we investigate the potential of harvesting energy from naturally evaporating water. Using weather data across the contiguous United States and a modified model of potential evaporation, we estimate the power availability, intermittency, and the changes in evaporation rates imposed by energy conversion. Our results indicate that natural evaporation can deliver power densities similar to existing renewable energy platforms and require little to no energy storage to match the varying power demands of urban areas. This model also predicts additional, and substantial, water savings by reducing evaporative losses. These findings suggest that evaporative energy harvesting can address significant challenges with water/energy interactions that could be of interest to the hydrology community.

  16. Correlation of ISS Electric Potential Variations with Mission Operations

    NASA Technical Reports Server (NTRS)

    Willis, Emily M.; Minow, Joseph I.; Parker, Linda Neergaard

    2014-01-01

    Spacecraft charging on the International Space Station (ISS) is caused by a complex combination of the low Earth orbit plasma environment, space weather events, operations of the high voltage solar arrays, and changes in the ISS configuration and orbit parameters. Measurements of the ionospheric electron density and temperature along the ISS orbit and variations in the ISS electric potential are obtained from the Floating Potential Measurement Unit (FPMU) suite of four plasma instruments (two Langmuir probes, a Floating Potential Probe, and a Plasma Impedance Probe) on the ISS. These instruments provide a unique capability for monitoring the response of the ISS electric potential to variations in the space environment, changes in vehicle configuration, and operational solar array power manipulation. In particular, rapid variations in ISS potential during solar array operations on time scales of tens of milliseconds can be monitored due to the 128 Hz sample rate of the Floating Potential Probe providing an interesting insight into high voltage solar array interaction with the space plasma environment. Comparing the FPMU data with the ISS operations timeline and solar array data provides a means for correlating some of the more complex and interesting ISS electric potential variations with mission operations. In addition, recent extensions and improvements to the ISS data downlink capabilities have allowed more operating time for the FPMU than ever before. The FPMU was operated for over 200 days in 2013 resulting in the largest data set ever recorded in a single year for the ISS. In this paper we provide examples of a number of the more interesting ISS charging events observed during the 2013 operations including examples of rapid charging events due to solar array power operations, auroral charging events, and other charging behavior related to ISS mission operations.

  17. Correlation of ISS Electric Potential Variations with Mission Operations

    NASA Technical Reports Server (NTRS)

    Willis, Emily M.; Minow, Joseph I.; Parker, Linda Neergaard

    2014-01-01

    Spacecraft charging on the International Space Station (ISS) is caused by a complex mix of the low Earth orbit plasma environment, space weather events, operations of the high voltage solar arrays, and changes in the ISS configuration and orbit parameters. Measurements of the ionospheric electron density and temperature along the ISS orbit and variations in the ISS electric potential are obtained from the Floating Potential Measurement Unit (FPMU) suite of four plasma instruments (two Langmuir probes, a Floating Potential Probe, and a Plasma Impedance Probe) on the ISS. These instruments provide a unique capability for monitoring the response of the ISS electric potential to variations in the space environment, changes in vehicle configuration, and operational solar array power manipulation. In particular, rapid variations in ISS potential during solar array operations on time scales of tens of milliseconds can be monitored due to the 128 Hz sample rate of the Floating Potential Probe providing an interesting insight into high voltage solar array interaction with the space plasma environment. Comparing the FPMU data with the ISS operations timeline and solar array data provides a means for correlating some of the more complex and interesting ISS electric potential variations with mission operations. In addition, recent extensions and improvements to the ISS data downlink capabilities have allowed more operating time for the FPMU than ever before. The FPMU was operated for over 200 days in 2013 resulting in the largest data set ever recorded in a single year for the ISS. This presentation will provide examples of a number of the more interesting ISS charging events observed during the 2013 operations including examples of rapid charging events due to solar array power operations, auroral charging events, and other charging behavior related to ISS mission operations.

  18. Potential for electricity generation from biomass residues in Cuba

    SciTech Connect

    Lora, E.S.

    1995-11-01

    The purpose of this paper is the study of the availability of major biomass residues in Cuba and the analysis of the electricity generation potential by using different technologies. An analysis of the changes in the country`s energy balance from 1988 up to date is presented, as well as a table with the availability study results and the energy equivalent for the following biomass residues: sugar cane bagasse and trash, rice and coffee husk, corn an cassava stalks and firewood. A total equivalent of 4.42 10{sup 6} tons/year of fuel-oil was obtained. Possible scenarios for the electricity production increase in the sugar industry are presented too. The analysis is carried out for a high stream parameter CEST and two BIG/GT system configurations. Limitations are introduced about the minimal milling capacity of the sugar mills for each technology. The calculated {open_quotes}real{close_quotes} electricity generation potential for BIG/GT systems, based on GE LM5000 CC gas turbines, an actual cane harvest of 58.0 10{sup 6} tons/year, half the available trash utilization and an specific steam consumption of 210 kg/tc, was 18601,0 GWh/year. Finally different alternatives are presented for low-scale electricity generation based on the other available agricultural residues.

  19. Magnetic field-aligned electric potentials in nonideal plasma flows

    NASA Technical Reports Server (NTRS)

    Schindler, K.; Hesse, M.; Birn, J.

    1991-01-01

    The electric field component parallel to the magnetic field arising from plasma flows which violate the frozen-in field condition of ideal magnetohydrodynamics is discussed. The quantity of interest is the potential U = integral E parallel ds where the integral is extended along field lines. It is shown that U can be directly related to magnetic field properties, expressed by Euler potentials, even when time-dependence is included. These results are applicable to earth's magnetosphere, to solar flares, to aligned-rotator models of compact objects, and to galactic rotation. On the basis of order-of-magnitude estimates, these results support the view that parallel electric fields associated with nonideal plasma flows might play an important role in cosmic particle acceleration.

  20. Heterobarrier for converting hot-phonon energy to electric potential

    NASA Astrophysics Data System (ADS)

    Shin, Seungha; Melnick, Corey; Kaviany, Massoud

    2013-02-01

    We show that hot phonons emitted in energy conversion or resistive processes can be converted to electric potential in heterobarrier structures. Using phonon and electron interaction kinetics and self-consistent ensemble Monte Carlo, we find the favorable conditions for unassisted absorption of hot phonons and design graded heterobarriers for their direct conversion into electric energy. Tandem barriers with nearly optical-phonon height allow for substantial potential gain without current loss. We find that 19% of hot phonons can be harvested with an optimized GaAs/AlxGa1-xAs barrier structure over a range of current and electron densities, thus enhancing the overall energy conversion efficiency and reducing waste heat.

  1. The soil electric potential signature of summer drought

    NASA Astrophysics Data System (ADS)

    Outcalt, S. I.; Hinkel, K. M.

    1990-03-01

    During the period from late April to early August, a timeseries of soil electric potential measurements in the upper 15 cm of mineral soil were collected daily at the University of Michigan Botanical Gardens using an automatic data collection system. These data, after conversion to a surrogate measure of electrolyte concentration, provide a unique record of the 1988 summer drought in a continental location. The effects of rainfall-dewfall electrolyte dilution, evaporation-induced electrolyte concentration and upward-downward soil water advection are well-illustrated in the data. These observations demonstrate that soil electric potential is an easily measured variable of high information content, especially when collected with other system-linked environmental data.

  2. Chemically induced electric field: flat band potential engineering

    NASA Astrophysics Data System (ADS)

    Bak, T.; Guo, Z.; Li, W.; Atanacio, A. J.; Nowotny, J.

    2012-10-01

    The present work considers engineering of the flat band potential, FBP, of metal oxides in a controlled manner. The aim is to minimise the energy losses related to recombination. The related experimental approaches include imposition of a chemically-induced electric field using the phenomena of segregation, diffusion and the formation of multilayer systems. This paper considers several basic phenomena that allow the modification of the surface charge and the space charge at the gas/solid and solid/liquid interfaces.

  3. Assessing Vulnerability of Electricity Generation Under Potential Future Droughts

    NASA Astrophysics Data System (ADS)

    Yan, E.; Tidwell, V. C.; Wigmosta, M. S.

    2014-12-01

    In the past few decades, the western US experienced increased sever, frequent, and prolonged droughts resulting in significant water availability issues, which raised questions as to how electricity sector might be vulnerable to future droughts. To improve our understanding of potential risks of electricity generation curtailment due to drought, an impact analysis was performed with a series of modeling tools including climate downscaling, competitive water-use calculator, hydrologic model for various hydrologic processes, and power-plant specific models. This presentation will demonstrate the predicted effects of potential droughts on power generation at a local level of the USGS 8-digit watersheds and individual power plants within the context of current and future characteristics of power system and water resource system.The study identified three potential drought scenarios based on historical drought records and projected climate changes from the GFDL and the PCM global climate models, for greenhouse gas emission scenarios A1B, A2, and B1 defined by the IPCC. The potential impacts under these three drought scenarios were evaluated with a hydrologic model constructed for the Pacific Northwest River Basin and California River Basin. The hydrologic model incorporates competitive water uses, climate forcing data corresponding to each of drought scenarios, and all major reservoirs that are currently supporting water withdrawal for various sectors and hydroelectric power generation. The hydrologic responses to drought scenarios predicted for each of the USGS 8-digit watersheds and reservoirs are used as input to power-plant specific models to quantify potential risk of curtailment at each power plant. The key findings from this study will help to improve understanding of spatial distribution of vulnerable power plants and watersheds as well as the scale of potential reduction of electricity generation under various drought scenarios. Beyond impacts to the existing

  4. Preparation and energy-saving application of polyurethane/phase change composite materials for electrical water heaters

    NASA Astrophysics Data System (ADS)

    Hu, Yougen; Zhao, Tao; Wu, Xiaolin; Lai, Maobai; Jiang, Chengming; Sun, Rong

    2012-04-01

    Thermal energy storage plays an important role in heat management because of the demand for developed energy conservation, and has applications in diverse areas, from buildings to textiles and clothings. In this study, we aimed to improve thermal characteristics of polyurethane rigid foams that have been widely used for thermal insulation in electrical water heaters. Through this work, paraffin waxes with melting point of 55~65°C act as phase change materials. Then the phase change materials were incorporated into the polyurethane foams at certain ratio. The polyurethane/phase change composite materials used as insulation layers in electrical water heaters performed the enthalpy value of 5~15 J/g. Energy efficiency of the electrical water heaters was tested according to the National Standard of China GB 21519-2008. Results show that 24 h energy consumption of the electrical water heaters manufactured by traditional polyurethane rigid foams and polyurethane/phase change material composites was 1.0612 kWh and 0.9833 kWh, respectively. The results further show that the energy-saving rate is 7.36%. These proved that polyurethane/phase change composite materials can be designed as thermal insulators equipped with electrical water heaters and have a significant effect on energy conservation.

  5. Preparation and energy-saving application of polyurethane/phase change composite materials for electrical water heaters

    NASA Astrophysics Data System (ADS)

    Hu, Yougen; Zhao, Tao; Wu, Xiaolin; Lai, Maobai; Jiang, Chengming; Sun, Rong

    2011-11-01

    Thermal energy storage plays an important role in heat management because of the demand for developed energy conservation, and has applications in diverse areas, from buildings to textiles and clothings. In this study, we aimed to improve thermal characteristics of polyurethane rigid foams that have been widely used for thermal insulation in electrical water heaters. Through this work, paraffin waxes with melting point of 55~65°C act as phase change materials. Then the phase change materials were incorporated into the polyurethane foams at certain ratio. The polyurethane/phase change composite materials used as insulation layers in electrical water heaters performed the enthalpy value of 5~15 J/g. Energy efficiency of the electrical water heaters was tested according to the National Standard of China GB 21519-2008. Results show that 24 h energy consumption of the electrical water heaters manufactured by traditional polyurethane rigid foams and polyurethane/phase change material composites was 1.0612 kWh and 0.9833 kWh, respectively. The results further show that the energy-saving rate is 7.36%. These proved that polyurethane/phase change composite materials can be designed as thermal insulators equipped with electrical water heaters and have a significant effect on energy conservation.

  6. The Future is Green: Tribal College Saving Water, Electricity--and Money

    ERIC Educational Resources Information Center

    Stevenson, Gelvin

    2005-01-01

    Tribal colleges and universities around the country are harnessing natural sources of energy on their campuses. Renewable energy and sustainable building design have many advantages--they save money and provide healthier learning and working environments while allowing people to live in greater harmony with the earth. This article discusses…

  7. Use of plant woody species electrical potential for irrigation scheduling.

    PubMed

    Ríos-Rojas, Liliana; Morales-Moraga, David; Alcalde, José A; Gurovich, Luis A

    2015-01-01

    The electrical response of plants to environmental stimuli can be measured and quantitatively related to the intensity of several stimulating sources, like temperature, solar radiation, soil water content, evapotranspiration rates, sap flow and dendrometric cycles. These relations can be used to assess the influence of different environmental situations on soil water availability to plants, defined as a steady state condition between leaf transpirative flow and soil water flow to plant roots. A restricted soil water flow due to soil dryness can trigger water stress in plants, if the atmospheric evaporative demand is high, causing partial stomata closure as a physiological response to avoid plant dehydration; water stressed and unstressed plants manifest a differential electrical response. Real time plant electrical response measurements can anticipate actions that prevent the plant reaching actual stress conditions, optimizing stomata gas exchange and photosynthetic rates. An electrophysiological sensor developed in this work, allows remote real-time recording information on plant electrical potential (EP) in the field, which is highly related to EP measurements obtained with a laboratory Keithley voltmeter sensor used in an highly controlled experimental setup. Our electrophysiological sensor is a wireless, autonomous devise, which transmits EP information via Internet to a data server. Using both types of sensors (EP electrodes with a Keithley voltmeter and the electrophysiological sensor), we measured in real time the electrical responses of Persea americana and Prunus domestica plants, to induced water deficits. The differential response for 2 scenarios: irrigation and water restriction is identified by a progressive change in slope on the daily maximal and minimal electric signal values in stressed plants, and a zero-slope for similar signals for well-watered plants. Results show a correspondence between measured signals obtained by our electrophysiological

  8. Use of plant woody species electrical potential for irrigation scheduling.

    PubMed

    Ríos-Rojas, Liliana; Morales-Moraga, David; Alcalde, José A; Gurovich, Luis A

    2015-01-01

    The electrical response of plants to environmental stimuli can be measured and quantitatively related to the intensity of several stimulating sources, like temperature, solar radiation, soil water content, evapotranspiration rates, sap flow and dendrometric cycles. These relations can be used to assess the influence of different environmental situations on soil water availability to plants, defined as a steady state condition between leaf transpirative flow and soil water flow to plant roots. A restricted soil water flow due to soil dryness can trigger water stress in plants, if the atmospheric evaporative demand is high, causing partial stomata closure as a physiological response to avoid plant dehydration; water stressed and unstressed plants manifest a differential electrical response. Real time plant electrical response measurements can anticipate actions that prevent the plant reaching actual stress conditions, optimizing stomata gas exchange and photosynthetic rates. An electrophysiological sensor developed in this work, allows remote real-time recording information on plant electrical potential (EP) in the field, which is highly related to EP measurements obtained with a laboratory Keithley voltmeter sensor used in an highly controlled experimental setup. Our electrophysiological sensor is a wireless, autonomous devise, which transmits EP information via Internet to a data server. Using both types of sensors (EP electrodes with a Keithley voltmeter and the electrophysiological sensor), we measured in real time the electrical responses of Persea americana and Prunus domestica plants, to induced water deficits. The differential response for 2 scenarios: irrigation and water restriction is identified by a progressive change in slope on the daily maximal and minimal electric signal values in stressed plants, and a zero-slope for similar signals for well-watered plants. Results show a correspondence between measured signals obtained by our electrophysiological

  9. Use of plant woody species electrical potential for irrigation scheduling

    PubMed Central

    Ríos-Rojas, Liliana; Morales-Moraga, David; Alcalde, José A; Gurovich, Luis A

    2015-01-01

    The electrical response of plants to environmental stimuli can be measured and quantitatively related to the intensity of several stimulating sources, like temperature, solar radiation, soil water content, evapotranspiration rates, sap flow and dendrometric cycles. These relations can be used to assess the influence of different environmental situations on soil water availability to plants, defined as a steady state condition between leaf transpirative flow and soil water flow to plant roots. A restricted soil water flow due to soil dryness can trigger water stress in plants, if the atmospheric evaporative demand is high, causing partial stomata closure as a physiological response to avoid plant dehydration; water stressed and unstressed plants manifest a differential electrical response. Real time plant electrical response measurements can anticipate actions that prevent the plant reaching actual stress conditions, optimizing stomata gas exchange and photosynthetic rates. An electrophysiological sensor developed in this work, allows remote real-time recording information on plant electrical potential (EP) in the field, which is highly related to EP measurements obtained with a laboratory Keithley voltmeter sensor used in an highly controlled experimental setup. Our electrophysiological sensor is a wireless, autonomous devise, which transmits EP information via Internet to a data server. Using both types of sensors (EP electrodes with a Keithley voltmeter and the electrophysiological sensor), we measured in real time the electrical responses of Persea americana and Prunus domestica plants, to induced water deficits. The differential response for 2 scenarios: irrigation and water restriction is identified by a progressive change in slope on the daily maximal and minimal electric signal values in stressed plants, and a zero-slope for similar signals for well-watered plants. Results show a correspondence between measured signals obtained by our electrophysiological

  10. Insights from Smart Meters: The Potential for Peak-Hour Savings from Behavior-Based Programs

    SciTech Connect

    Todd, Annika; Perry, Michael; Smith, Brian; Sullivan, Michael; Cappers, Peter; Goldman, Charles

    2014-03-25

    The rollout of smart meters in the last several years has opened up new forms of previously unavailable energy data. Many utilities are now able in real-time to capture granular, household level interval usage data at very high-frequency levels for a large proportion of their residential and small commercial customer population. This can be linked to other time and locationspecific information, providing vast, constantly growing streams of rich data (sometimes referred to by the recently popular buzz word, “big data”). Within the energy industry there is increasing interest in tapping into the opportunities that these data can provide. What can we do with all of these data? The richness and granularity of these data enable many types of creative and cutting-edge analytics. Technically sophisticated and rigorous statistical techniques can be used to pull interesting insights out of this highfrequency, human-focused data. We at LBNL are calling this “behavior analytics”. This kind of analytics has the potential to provide tremendous value to a wide range of energy programs. For example, highly disaggregated and heterogeneous information about actual energy use would allow energy efficiency (EE) and/or demand response (DR) program implementers to target specific programs to specific households; would enable evaluation, measurement and verification (EM&V) of energy efficiency programs to be performed on a much shorter time horizon than was previously possible; and would provide better insights in to the energy and peak hour savings associated with specifics types of EE and DR programs (e.g., behavior-based (BB) programs). In this series, “Insights from Smart Meters”, we will present concrete, illustrative examples of the type of value that insights from behavior analytics of these data can provide (as well as pointing out its limitations). We will supply several types of key findings, including: • Novel results, which answer questions the industry

  11. Electric potential distributions at the interface between plasmasheet clouds

    NASA Technical Reports Server (NTRS)

    Evans, D. S.; Roth, M.; Lemaire, J.

    1987-01-01

    At the interface between two plasma clouds with different densities, temperatures, and/or bulk velocities, there are large charge separation electric fields which can be modeled in the framework of a collisionless theory for tangential discontinuities. Two different classes of layers were identified: the first one corresponds to (stable) ion layers which are thicker than one ion Lamor radius; the second one corresponds to (unstable) electron layers which are only a few electron Larmor radii thick. It is suggested that these thin electron layers with large electric potential gradients (up to 400 mV/m) are the regions where large-amplitude electrostatic waves are spontaneously generated. These waves scatter the pitch angles of the ambient plasmasheet electron into the atmospheric loss cone. The unstable electron layers can therefore be considered as the seat of strong pitch angle scattering for the primary auroral electrons.

  12. Analysis of Energy Saving and Environmental Characteristics of Electric Vehicle in Regionally-Disaggregated World Energy Model

    NASA Astrophysics Data System (ADS)

    Komiyama, Ryoichi; Fujii, Yasumasa

    This paper investigates the impact of an extensive introduction of electric vehicle (EV) and plug-in hybrid vehicle (PHEV) into global energy system towards 2050. The significant growth of automobile ownership in emerging countries is likely to increase the world oil demand and the associated carbon dioxide emissions. In order to address these energy security and environmental concerns, the deployment of clean energy vehicles, such as EV and PHEV, are expected to play a crucial role due to its high fuel efficiency. On these backgrounds, we develop both global energy system model and world vehicle penetration model, which are able to explicitly analyze the impact of EV introduction into seasonal daily electric load curve considering its specific electricity charging profile to 2050. Simulation results confirm that EV deployment contributes to energy conservation, because oil demand reduction outstrips the growth in its electricity demand and the associated fuel input into power generation mix. Concerning carbon dioxide abatement, the magnitude of the impact relies on the carbon-intensity of power generation mix. If the intensity is low enough to make sure the carbon mitigation effect by EV fuel saving, the emissions reduction is well ensured. It should be noted, however, that, in the regions with high carbon intensity in power generation mix, carbon emissions per mileage of EV is almost equivalent to that of efficient gasoline vehicle like hybrid vehicle and PHEV is slightly higher than hybrid vehicle.

  13. Impacts of Potential Future Droughts on Electricity Generation

    NASA Astrophysics Data System (ADS)

    Yan, E.; Wigmosta, M. S.; Tidwell, V. C.; King, C. W.

    2013-12-01

    In 2011, the state of Texas experienced the worst single-year drought on record. This recent extreme climate event raised questions as to how future droughts might impact ERCOT operations. To improve our understanding of potential risks of electricity generation curtailment due to drought, an impact analysis was performed with a series of modeling tools including climate downscaling, competitive water-use calculator, hydrologic model for various hydrologic processes, and power-plant specific models. This presentation will demonstrate the predicted effects of potential future droughts on power generation at a local level of the USGS 8-digit watersheds and power plants within the context of long-term transmission planning. The study identified three potential drought scenarios (single- and multiple-year droughts) based on historical drought records and projected climate changes from the GFDL and the PCM global climate models, for greenhouse gas emission scenarios A1B, A2, and B1 defined by the IPCC. The potential impacts under these three drought scenarios were evaluated with a hydrologic model constructed for the Texas-Gulf river basin. The Texas-Gulf hydrologic model incorporates competitive water uses, climate forcing data corresponding to each of drought scenarios, and 125 reservoirs that are currently supporting water withdrawal for various sectors and cooling water for power generation. The hydrologic responses to drought scenarios predicted for each of the USGS 8-digit watersheds (such as evapotranspiration, soil water, water yield from watersheds, stream flow, and water storage in reservoirs) provide a bases to assess if power plants potentially at risk of being of derated and watersheds are vulnerable to droughts. The key findings from this study will help to improve understanding of spatial distribution of power plants at risk and vulnerable watersheds as well as the scale of potential reduction of electricity generation. Beyond impacts to the existing

  14. Angular selective window systems: Assessment of technical potential for energy savings

    DOE PAGES

    Fernandes, Luis L.; Lee, Eleanor S.; McNeil, Andrew; Jonsson, Jacob C.; Nouidui, Thierry; Pang, Xiufeng; Hoffmann, Sabine

    2014-10-16

    Static angular selective shading systems block direct sunlight and admit daylight within a specific range of incident solar angles. The objective of this study is to quantify their potential to reduce energy use and peak demand in commercial buildings using state-of-the art whole-building computer simulation software that allows accurate modeling of the behavior of optically-complex fenestration systems such as angular selective systems. Three commercial systems were evaluated: a micro-perforated screen, a tubular shading structure, and an expanded metal mesh. This evaluation was performed through computer simulation for multiple climates (Chicago, Illinois and Houston, Texas), window-to-wall ratios (0.15-0.60), building codes (ASHRAEmore » 90.1-2004 and 2010) and lighting control configurations (with and without). The modeling of the optical complexity of the systems took advantage of the development of state-of-the-art versions of the EnergyPlus, Radiance and Window simulation tools. Results show significant reductions in perimeter zone energy use; the best system reached 28% and 47% savings, respectively without and with daylighting controls (ASHRAE 90.1-2004, south facade, Chicago,WWR=0.45). As a result, angular selectivity and thermal conductance of the angle-selective layer, as well as spectral selectivity of low-emissivity coatings, were identified as factors with significant impact on performance.« less

  15. Angular selective window systems: Assessment of technical potential for energy savings

    SciTech Connect

    Fernandes, Luis L.; Lee, Eleanor S.; McNeil, Andrew; Jonsson, Jacob C.; Nouidui, Thierry; Pang, Xiufeng; Hoffmann, Sabine

    2014-10-16

    Static angular selective shading systems block direct sunlight and admit daylight within a specific range of incident solar angles. The objective of this study is to quantify their potential to reduce energy use and peak demand in commercial buildings using state-of-the art whole-building computer simulation software that allows accurate modeling of the behavior of optically-complex fenestration systems such as angular selective systems. Three commercial systems were evaluated: a micro-perforated screen, a tubular shading structure, and an expanded metal mesh. This evaluation was performed through computer simulation for multiple climates (Chicago, Illinois and Houston, Texas), window-to-wall ratios (0.15-0.60), building codes (ASHRAE 90.1-2004 and 2010) and lighting control configurations (with and without). The modeling of the optical complexity of the systems took advantage of the development of state-of-the-art versions of the EnergyPlus, Radiance and Window simulation tools. Results show significant reductions in perimeter zone energy use; the best system reached 28% and 47% savings, respectively without and with daylighting controls (ASHRAE 90.1-2004, south facade, Chicago,WWR=0.45). As a result, angular selectivity and thermal conductance of the angle-selective layer, as well as spectral selectivity of low-emissivity coatings, were identified as factors with significant impact on performance.

  16. Potential cost savings from investments in energy-conserving irrigation systems

    SciTech Connect

    Patton, W.P.; Wilfert, G.L.; Harrer, B.J.; Clark, M.A.; Sherman, K.L.

    1982-10-01

    A comparative analysis is presented of the levelized costs of selected irrigation systems, with an emphasis on the costs and benefits of energy savings. The net economic benefits are evaluated, measured as energy cost savings minus additional capital and operating costs, of some energy-conserving systems. Energy use in irrigation and descriptions of both the conventional and the energy-saving technologies involved in the analysis are discussed. The approach used in the analysis is outlined, and comparative analysis results are discussed. Detailed cost information is presented by state. (LEW)

  17. Power-Law Scaling in the Brain Surface Electric Potential

    PubMed Central

    Miller, Kai J.; Sorensen, Larry B.; Ojemann, Jeffrey G.; den Nijs, Marcel

    2009-01-01

    Recent studies have identified broadband phenomena in the electric potentials produced by the brain. We report the finding of power-law scaling in these signals using subdural electrocorticographic recordings from the surface of human cortex. The power spectral density (PSD) of the electric potential has the power-law form from 80 to 500 Hz. This scaling index, , is conserved across subjects, area in the cortex, and local neural activity levels. The shape of the PSD does not change with increases in local cortical activity, but the amplitude, , increases. We observe a “knee” in the spectra at , implying the existence of a characteristic time scale . Below , we explore two-power-law forms of the PSD, and demonstrate that there are activity-related fluctuations in the amplitude of a power-law process lying beneath the rhythms. Finally, we illustrate through simulation how, small-scale, simplified neuronal models could lead to these power-law observations. This suggests a new paradigm of non-oscillatory “asynchronous,” scale-free, changes in cortical potentials, corresponding to changes in mean population-averaged firing rate, to complement the prevalent “synchronous” rhythm-based paradigm. PMID:20019800

  18. A Study of the Energy-Saving Potential of Metal Roofs Incorporating Dynamic Insulation Systems

    SciTech Connect

    Biswas, Kaushik; Miller, William A; Kriner, Scott; Manlove, Gary

    2013-01-01

    This article presents various metal roof configurations that were tested at Oak Ridge National Laboratory in Tennessee, U.S. between 2009 and 2013, and describes their potential for reducing the attic-generated space-conditioning loads. These roofs contained different combinations of phase-change material, rigid insulation, low emittance surface, and above-sheathing ventilation with standing-seam metal panels on top. These roofs were designed to be installed on existing roofs decks, or on top of asphalt shingles for retrofit construction. All the tested roofs showed the potential for substantial energy savings compared to an asphalt shingle roof, which was used as a control for comparison. The roofs were constructed on a series of adjacent attics separated at the gables using thick foam insulation. The attics were built on top of a conditioned room. All attics were vented at the soffit and ridge. The test roofs and attics were instrumented with an array of thermocouples. Heat flux transducers were installed in the roof deck and attic floor (ceiling) to measure the heat flows through the roof and between the attic and conditioned space below. Temperature and heat flux data were collected during the heating, cooling and swing seasons over a three-year period. Data from previous years of testing have been published. Here, data from the latest roof configurations being tested in year three of the project are presented. All test roofs were highly effective in reducing the heat flows through the roof and ceiling, and in reducing the diurnal attic-temperature fluctuations.

  19. Corticospinal potentials after electrical and magnetic stimulation in man.

    PubMed

    Berardelli, A; Inghilleri, M; Cruccu, G; Manfredi, M

    1991-01-01

    The present report deals with our study of the descending volley evoked by both electrical and magnetic transcranial stimulation in man. We discuss the differences of these two techniques specifically as regards the latency and amplitude of evoked potentials. In both cases, electrodes were placed either in the epidural space or directly on the spinal cord. Following electrical stimulation, the descending volley consisted of an early wave which appeared at low stimulation intensity and increased in amplitude and decreased in latency when the strength of the stimulus was increased. At high stimulation intensities the early wave was followed by later waves which travel at the same speed as the initial wave. By delivering paired cortical stimuli, the early wave evoked by the test stimuli is present at 1-msec interval and progressively recovered with longer intervals. The recovery cycle of the later waves is also extremely short. Following magnetic stimulation, the descending volley also consisted of an initial wave followed by later waves. The initial wave has a slightly longer latency, a higher threshold and a smaller amplitude than the early wave evoked by electrical stimulation. The results are discussed with reference to the D and I waves recorded from the pyramidal tract in animals.

  20. Potential for deserts to supply reliable renewable electric power

    NASA Astrophysics Data System (ADS)

    Labordena, Mercè; Lilliestam, Johan

    2015-04-01

    To avoid dangerous climate change, the electricity systems must be decarbonized by mid-century. The world has sufficient renewable electricity resources for complete power sector decarbonization, but an expansion of renewables poses several challenges for the electricity systems. First, wind and solar PV power are intermittent and supply-controlled, making it difficult to securely integrate this fluctuating generation into the power systems. Consequently, power sources that are both renewable and dispatchable, such as biomass, hydro and concentrating solar power (CSP), are particularly important. Second, renewable power has a low power density and needs vast areas of land, which is problematic both due to cost reasons and due to land-use conflicts, in particular with agriculture. Renewable and dispatchable technologies that can be built in sparsely inhabited regions or on land with low competition with agriculture would therefore be especially valuable; this land-use competition greatly limits the potential for hydro and biomass electricity. Deserts, however, are precisely such low-competition land, and are at the same time the most suited places for CSP generation, but this option would necessitate long transmission lines from remote places in the deserts to the demand centers such as big cities. We therefore study the potential for fleets of CSP plants in the large deserts of the world to produce reliable and reasonable-cost renewable electricity for regions with high and/or rapidly increasing electricity demand and with a desert within or close to its borders. The regions in focus here are the European Union, North Africa and the Middle East, China and Australia. We conduct the analysis in three steps. First, we identify the best solar generation areas in the selected deserts using geographic information systems (GIS), and applying restrictions to minimize impact on biodiversity, soils, human heath, and land-use and land-cover change. Second, we identify

  1. Electrical stimulation of the hypoglossal nerve: a potential therapy.

    PubMed

    Schwartz, Alan R; Smith, Philip L; Oliven, Arie

    2014-02-01

    Obstructive sleep apnea is characterized by recurrent episodes of pharyngeal collapse, which result from a decrease in pharyngeal dilator muscle tone. The genioglossus is a major pharyngeal dilator that maintains airway patency during sleep. Early studies in animal and humans have demonstrated that electrical stimulation of this muscle reduces pharyngeal collapsibility, increases airflow, and mitigates obstructive sleep apnea. These findings impelled the development of fully implantable hypoglossal nerve stimulating systems (HGNS), for which feasibility trial results are now available. These pilot studies have confirmed that hypoglossal nerve stimulation can prevent pharyngeal collapse without arousing patients from sleep. Potentially, a substantial segment of the patient population with obstructive sleep apnea can be treated with this novel approach. Furthermore, the feasibility trial findings suggest that the therapeutic potential of HGNS can be optimized by selecting patients judiciously, titrating the stimulus intensity optimally, and characterizing the underlying function and anatomy of the pharynx. These strategies are currently being examined in ongoing pivotal trials of HGNS.

  2. Ion separations based on electrical potentials nanoporous and microporous membranes

    NASA Astrophysics Data System (ADS)

    Armstrong, Jason

    This dissertation examines several types of ion separations in nanometer to micrometer pores in membranes. Membranes provide an attractive platform for ion separations, primarily because they operate continuously (i.e. not in a batch mode), and small pores offer the potential for ion separation based on charge and electrophoretic mobility differences. Initial studies employed charged, nanoporous membranes to separate monovalent and divalent ions. Adsorption of polyelectrolyte multilayers in nanoporous membranes afforded control over the surface charge and pore radii in track-etched membranes, and electrostatic ion-exclusion, particularly for divalent ions, occurred in these membranes because the electrical double layer filled the entire nanopore. Initial experiments employed adsorption of (PSS/PAH) multilayers in the 50-nm diameter pores of PCTE membranes to give a K+/Mg2+ selectivity of ~10 in pressure-driven dead-end filtration. Adsorption of (PSS/PAH) 1 films in 30-nm pores gave a similar K+/Mg2+ selectivity with a simpler modification procedure. Separations utilizing (PSS/PAH)1 films in 30-nm pores showed the lowest ion rejections with high ion concentrations, consistent with enhanced screening of the electrical double layer at high ionic strength. However, solutions with < 5 mM ionic strength exhibited essentially 100% Mg2+ rejections (the Mg2+ concentration in the permeate was below the method detection limit). Moreover, K+ rejections increased in the presence of Mg2+, which may stem from Mg2+-adsorption within the PEM and increased surface charge. Finally, separation of Br- and SO42- with a PSS1-modified, 30-nm PCTE membrane validated the exclusion mechanism for anions. The average Br-/SO42- selectivity was 3.4 +/- 0.8 for a solution containing 0.5 mM NaBr and 0.5 mM Na2SO4. The low selectivity in this case likely stems from a relatively large pore. The membranes used for the separation of monovalent and divalent ions also facilitated separation of

  3. China's Pathways to Achieving 40% ~ 45% Reduction in CO{sub 2} Emissions per Unit of GDP in 2020: Sectoral Outlook and Assessment of Savings Potential

    SciTech Connect

    Zheng, Nina; Fridley, David; Zhou, Nan; Levine, Mark; Price, Lynn; Ke, Jing

    2011-09-30

    Achieving China’s goal of reducing its carbon intensity (CO{sub 2} per unit of GDP) by 40% to 45% percent below 2005 levels by 2020 will require the strengthening and expansion of energy efficiency policies across the buildings, industries and transport sectors. This study uses a bottom-up, end-use model and two scenarios -- an enhanced energy efficiency (E3) scenario and an alternative maximum technically feasible energy efficiency improvement (Max Tech) scenario – to evaluate what policies and technical improvements are needed to achieve the 2020 carbon intensity reduction target. The findings from this study show that a determined approach by China can lead to the achievement of its 2020 goal. In particular, with full success in deepening its energy efficiency policies and programs but following the same general approach used during the 11th Five Year Plan, it is possible to achieve 49% reduction in CO{sub 2} emissions per unit of GDP (CO{sub 2} emissions intensity) in 2020 from 2005 levels (E3 case). Under the more optimistic but feasible assumptions of development and penetration of advanced energy efficiency technology (Max Tech case), China could achieve a 56% reduction in CO{sub 2} emissions intensity in 2020 relative to 2005 with cumulative reduction of energy use by 2700 Mtce and of CO{sub 2} emissions of 8107 Mt CO{sub 2} between 2010 and 2020. Energy savings and CO{sub 2} mitigation potential varies by sector but most of the energy savings potential is found in energy-intensive industry. At the same time, electricity savings and the associated emissions reduction are magnified by increasing renewable generation and improving coal generation efficiency, underscoring the dual importance of end-use efficiency improvements and power sector decarbonization.

  4. Analysis of energy-saving potential in residential buildings in Xiamen City and its policy implications for southern China

    NASA Astrophysics Data System (ADS)

    Guo, Fei

    The buildings sector is the largest energy-consuming sector in the world. Residential buildings consume about three-quarters of the final energy in the buildings sector. Promoting residential energy savings is in consequence critical for addressing many energy-use-related environmental challenges, such as climate change and air pollution. Given China's robust economic growth and fast urbanization, it is now a critical time to develop policy interventions on residential energy use in the nation. With this as a background, this dissertation explores effective policy intervention opportunities in southern China through analyzing the residential energy-saving potential, using the city of Xiamen as a case study. Four types of residential energy-saving potential are analyzed: technical potential, economic potential, maximum achievable potential (MAP), and possible achievable potential (PAP). Of these, the first two types are characterized as static theoretical evaluation, while the last two represent dynamic evaluation within a certain time horizon. The achievable potential analyses are rarely seen in existing literature. The analytical results reveal that there exists a significant technical potential for residential energy savings of about 20.9-24.9% in the city of Xiamen. Of the technical potential, about two-thirds to four-fifths are cost-effective from the government or society perspective. The cost-effectiveness is evaluated by comparing the "Levelized Cost of Conserved Energy (LCOCE)" of available advanced technical measures with the "Actual Cost" of conserved energy. The "Actual Cost" of energy is defined by adding the environmental externalities costs and hidden government subsidies over the retail prices of energy. The achievable potential analyses are particularly based on two key realistic factors: 1) the gradual ramping-up adoption process of advanced technical measures; and 2) individuals' adoption-decision making on them. For implementing the achievable

  5. Full-scale in-line hydrolysis and simulation for potential energy and resource savings in activated sludge--a case study.

    PubMed

    Hey, Tobias; Jönsson, Karin; Jansen, Jes la Cour

    2012-01-01

    The potential effects of altering primary settlers during biological in-line hydrolysis and converting a nitrifying activated sludge process into a partial pre-denitrification process for the purpose of resource conservation were evaluated. A full-scale primary sludge hydrolysis experiment was performed at a wastewater treatment plant and implemented in a dynamic modelling tool based on ASM2d. The full-scale hydrolysis experiment achieved a volatile fatty acid (VFA) production of 43 g COD(HAc) x m(-3) with no release of ammonium. Additional nitrogen removal of 44 t N x a(-1) was simulated, and the produced hydrolysate was able to replace 50% of the annual ethanol usage. Furthermore, 196 MWh of electricity per annum could be saved through the reduction of ethanol production and the optimization of the operation strategy of the activated sludge tank by operating a different number of anoxic zones.

  6. Literature Review of the Potential Energy Savings and Retention Water from Green Roofs in Comparison with Conventional Ones

    NASA Astrophysics Data System (ADS)

    Tselekis, Kyriakoulis

    2012-09-01

    The objective of this study is the comparison of green roof systems with conventional isolated and non-isolated ones in order to identify the potential energy savings of green roofs and the benefits provided in comparison with the cost of construction to the buildings. The region of interest is the Watergraafsmeer area in the city of Amsterdam. The method evaluates literature reports - mostly from 2003 to 2010 - that present the advantages of green roofs. Examples in real implementation of green roofs in USA, UK and Germany, retention of rainfall and a Life Cycle Assessment from a residential construction in Madrid will be introduced, showing the energy savings from insulation and heating/cooling that can be gained. All the reports have shown a reduction in energy costs and in runoff of water. Hence, costs and retrofitting potential completes the research. The age of buildings and the absence of insulation make green roofs an ideal alternative project for the retrofit of Watergraafsmeer.

  7. Dimensional Analysis and Electric Potential Due to a Uniformly Charged Sheet

    ERIC Educational Resources Information Center

    Aghamohammadi, Amir

    2011-01-01

    Dimensional analysis, superposition principle, and continuity of electric potential are used to study the electric potential of a uniformly charged square sheet on its plane. It is shown that knowing the electric potential on the diagonal and inside the square sheet is equivalent to knowing it everywhere on the plane of the square sheet. The…

  8. Water savings potentials of irrigation systems: global simulation of processes and linkages

    NASA Astrophysics Data System (ADS)

    Jägermeyr, J.; Gerten, D.; Heinke, J.; Schaphoff, S.; Kummu, M.; Lucht, W.

    2015-07-01

    Global agricultural production is heavily sustained by irrigation, but irrigation system efficiencies are often surprisingly low. However, our knowledge of irrigation efficiencies is mostly confined to rough indicative estimates for countries or regions that do not account for spatiotemporal heterogeneity due to climate and other biophysical dependencies. To allow for refined estimates of global agricultural water use, and of water saving and water productivity potentials constrained by biophysical processes and also non-trivial downstream effects, we incorporated a process-based representation of the three major irrigation systems (surface, sprinkler, and drip) into a bio- and agrosphere model, LPJmL. Based on this enhanced model we provide a gridded world map of irrigation efficiencies that are calculated in direct linkage to differences in system types, crop types, climatic and hydrologic conditions, and overall crop management. We find pronounced regional patterns in beneficial irrigation efficiency (a refined irrigation efficiency indicator accounting for crop-productive water consumption only), due to differences in these features, with the lowest values (< 30 %) in south Asia and sub-Saharan Africa and the highest values (> 60 %) in Europe and North America. We arrive at an estimate of global irrigation water withdrawal of 2469 km3 (2004-2009 average); irrigation water consumption is calculated to be 1257 km3, of which 608 km3 are non-beneficially consumed, i.e., lost through evaporation, interception, and conveyance. Replacing surface systems by sprinkler or drip systems could, on average across the world's river basins, reduce the non-beneficial consumption at river basin level by 54 and 76 %, respectively, while maintaining the current level of crop yields. Accordingly, crop water productivity would increase by 9 and 15 %, respectively, and by much more in specific regions such as in the Indus basin. This study significantly advances the global

  9. Potential impacts of electric vehicles on air quality in Taiwan.

    PubMed

    Li, Nan; Chen, Jen-Ping; Tsai, I-Chun; He, Qingyang; Chi, Szu-Yu; Lin, Yi-Chiu; Fu, Tzung-May

    2016-10-01

    The prospective impacts of electric vehicle (EV) penetration on the air quality in Taiwan were evaluated using an air quality model with the assumption of an ambitious replacement of current light-duty vehicles under different power generation scenarios. With full EV penetration (i.e., the replacement of all light-duty vehicles), CO, VOCs, NOx and PM2.5 emissions in Taiwan from a fleet of 20.6 million vehicles would be reduced by 1500, 165, 33.9 and 7.2Ggyr(-1), respectively, while electric sector NOx and SO2 emissions would be increased by up to 20.3 and 12.9Ggyr(-1), respectively, if the electricity to power EVs were provided by thermal power plants. The net impacts of these emission changes would be to reduce the annual mean surface concentrations of CO, VOCs, NOx and PM2.5 by about 260, 11.3, 3.3ppb and 2.1μgm(-3), respectively, but to increase SO2 by 0.1ppb. Larger reductions tend to occur at time and place of higher ambient concentrations and during high pollution events. Greater benefits would clearly be attained if clean energy sources were fully encouraged. EV penetration would also reduce the mean peak-time surface O3 concentrations by up to 7ppb across Taiwan with the exception of the center of metropolitan Taipei where the concentration increased by <2ppb. Furthermore, full EV penetration would reduce annual days of O3 pollution episodes by ~40% and PM2.5 pollution episodes by 6-10%. Our findings offer important insights into the air quality impacts of EV and can provide useful information for potential mitigation actions.

  10. Potential impacts of electric vehicles on air quality in Taiwan.

    PubMed

    Li, Nan; Chen, Jen-Ping; Tsai, I-Chun; He, Qingyang; Chi, Szu-Yu; Lin, Yi-Chiu; Fu, Tzung-May

    2016-10-01

    The prospective impacts of electric vehicle (EV) penetration on the air quality in Taiwan were evaluated using an air quality model with the assumption of an ambitious replacement of current light-duty vehicles under different power generation scenarios. With full EV penetration (i.e., the replacement of all light-duty vehicles), CO, VOCs, NOx and PM2.5 emissions in Taiwan from a fleet of 20.6 million vehicles would be reduced by 1500, 165, 33.9 and 7.2Ggyr(-1), respectively, while electric sector NOx and SO2 emissions would be increased by up to 20.3 and 12.9Ggyr(-1), respectively, if the electricity to power EVs were provided by thermal power plants. The net impacts of these emission changes would be to reduce the annual mean surface concentrations of CO, VOCs, NOx and PM2.5 by about 260, 11.3, 3.3ppb and 2.1μgm(-3), respectively, but to increase SO2 by 0.1ppb. Larger reductions tend to occur at time and place of higher ambient concentrations and during high pollution events. Greater benefits would clearly be attained if clean energy sources were fully encouraged. EV penetration would also reduce the mean peak-time surface O3 concentrations by up to 7ppb across Taiwan with the exception of the center of metropolitan Taipei where the concentration increased by <2ppb. Furthermore, full EV penetration would reduce annual days of O3 pollution episodes by ~40% and PM2.5 pollution episodes by 6-10%. Our findings offer important insights into the air quality impacts of EV and can provide useful information for potential mitigation actions. PMID:27285533

  11. Elimination of Potential Electrical Stress During EMC (CS01) Testing

    NASA Technical Reports Server (NTRS)

    Erickson, Kenneth P.; Whittlesey, Albert C.; Vorperian, Vatche

    2006-01-01

    This viewgraph presentation reviews possible ways to eliminate electrical stress during Electromagneticic Compatibility (EMC) testing. The presentation reviews tests that have had problems due to electrical stress. On December 5, 1995 Cassini Radar instrument failed a functional test in preparation for EMC conducted susceptibility (CSO 1 ) testing. The instrument power supply did not turn on as required, and failure occurred prior to injection of CS test stimulus. A investigation of the failure was conducted. A PSPICE simulation of Cassini Radar 30V line using the EMC test setup was performed; the result of the simulation was an oscillation on the 30V input of the power supply. In another case: on December 28, 1999 an oscillation occurred on the input power line of the SlRTF Infrared Array Camera (IRAC) while preparing to perform CSOI testing, Resulted in damage to flight hardware. Subsequent to failure, JPL provided GSFC history and corrective action from Cassini Radar CSOI test failure GSFC implemented the same corrective action as JPL, except that the value of the resistor connected across the isolation transformer primary winding is 2.5 ohms instead of 50 ohms. Three recommendations are made: (1) Make EMC test community aware of the problem and potential solutions by presenting papers at major environmental test conferences (2) Include warnings and safeguards in EMC test requirements and procedures (3) Try to convince EMC test equipment suppliers to design a CSOl test fixture similar to fixture shown in the diagram

  12. Ergonomics work stations decreases the health impairment and saves electrical energy at the woodworking workshop in Bali, Indonesia.

    PubMed

    Sudiajeng, Lilik; Adiputra, Nyoman; Leibbrandt, Richard

    2012-12-01

    This research was conducted to assess the positive effect of the ergonomics work station on the health impairment and electrical energy usage at the woodworking workshop in Bali, Indonesia. Woodworking workshops are dangerous, particularly when they are used improperly. Workers are exposed to health hazards that cause health impairment and inefficiencies in their work conditions. A preliminary study at a woodworking workshop at the Bali State Polytechnic showed that the work station was not suitable to body size of the participants and caused awkward postures. In addition, there was also an inappropriate physical work environment. Both inappropriate work station and physical work environment caused participants to be less active and motivated. This paper reports on an experimental study into the effects of an ergonomic intervention at this workshop. The participants were 2 groups of male students with 10 participants in each group. The first group performed the task with the original work station as a control group, while the second group performed the task with the new work station. The study found a significant difference between groups (p < 0.05) both for the health impairment and the electrical energy usage. The ergonomics intervention on the work station decreased the working heart rate (16.7%), the total score of musculoskeletal disorders (17.3%), and the total score of psychological fatigue (21.5%). Furthermore, it also decreased the electrical energy usage (38.7%). This shows that an ergonomics intervention on work station decreased the health impairment and saved electrical energy usage. It also protected the workers from woodworking hazards and allowed participants to perform their tasks in healthy, safe, convenient and efficient work conditions.

  13. Saving Lives.

    ERIC Educational Resources Information Center

    Moon, Daniel

    2002-01-01

    Advises schools on how to establish an automated external defibrillator (AED) program. These laptop-size devices can save victims of sudden cardiac arrest by delivering an electrical shock to return the heartbeat to normal. Discusses establishing standards, developing a strategy, step-by-step advice towards establishing an AED program, and school…

  14. Identification of potential locations of electric vehicle supply equipment

    NASA Astrophysics Data System (ADS)

    Brooker, R. Paul; Qin, Nan

    2015-12-01

    Proper placement of electric vehicle supply equipment (charging stations) requires an understanding of vehicle usage patterns. Using data from the National Household Travel Survey on vehicle mileage and destination patterns, analyses were performed to determine electric vehicles' charging needs, as a function of battery size and state of charge. This paper compares electric vehicle charging needs with Department of Energy electric vehicle charging data from real-world charging infrastructure. By combining the electric vehicles charging needs with charging data from real-world applications, locations with high electric vehicle charging likelihood are identified.

  15. Efficient motor saves power costs by trading electricity for natural gas

    SciTech Connect

    1995-08-01

    Casinghead gas provides inexpensive energy to drive the PowerPac pumpjack motor at a lower cost than an electric power plant. The PowerPAc is a 454-cubic-inch General Motors V-8 modified to run on natural gas. The engine will push 500 to 600 pound/feet of torque at low revolutions per minute. Engine efficiency, air emissions, and cost are discussed.

  16. Analysis of Household Electricity Consumption Patterns and Economy of Water Heating Shifting and Saving Bulbs

    NASA Astrophysics Data System (ADS)

    Rosin, Argo; Moller, Taavi; Lehtla, Madis; Hoimoja, Hardi

    2010-01-01

    This article analyses household electricity consumption based on an object in Estonia. Energy consumption of workday and holiday by loads (including high and low tariff energy consumption) is discussed. The final part describes the evaluation of profitability of common investments of consumption shifting and replacing inefficient devices with more efficient ones. Additionally it describes shifting problems and shifting equipment profitability in real-time tariff system.

  17. Load shift potential of electric vehicles in Europe

    NASA Astrophysics Data System (ADS)

    Babrowski, Sonja; Heinrichs, Heidi; Jochem, Patrick; Fichtner, Wolf

    2014-06-01

    Many governments highly encourage electric mobility today, aiming at a high market penetration. This development would bring forth an impact on the energy system, which strongly depends on the driving and charging behavior of the users. While an uncontrolled immediate charging might strain the local grid and/or higher peak loads, there are benefits to be gained by a controlled charging. We examine six European mobility studies in order to display the effects of controlled and uncontrolled unidirectional charging. Taking into account country-specific driving patterns, we generate for each country a charging load curve corresponding to uncontrolled charging and consider the corresponding parking time at charging facilities in order to identify load shift potentials. The main results are that besides the charging power of the vehicles, the possibility to charge at the work place has a significant influence on the uncontrolled charging curve. Neither national nor regional differences are as significant. When charging is only possible at home, the vehicle availability at charging facilities during the day for all countries is at least 24%. With the additional possibility to charge at work, at least 45% are constantly available. Accordingly, we identified a big potential for load shifting through controlled charging.

  18. Eye movements and brain electric potentials during reading.

    PubMed

    Kliegl, Reinhold; Dambacher, Michael; Dimigen, Olaf; Jacobs, Arthur M; Sommer, Werner

    2012-03-01

    The development of theories and computational models of reading requires an understanding of processing constraints, in particular of timelines related to word recognition and oculomotor control. Timelines of word recognition are usually determined with event-related potentials (ERPs) recorded under conditions of serial visual presentation (SVP) of words; timelines of oculomotor control are derived from parameters of eye movements (EMs) during natural reading. We describe two strategies to integrate these approaches. One is to collect ERPs and EMs in separate SVP and natural reading experiments for the same experimental material (but different subjects). The other strategy is to co-register EMs and ERPs during natural reading from the same subjects. Both strategies yield data that allow us to determine how lexical properties influence ERPs (e.g., the N400 component) and EMs (e.g., fixation durations) across neighboring words. We review our recent research on the effects of frequency and predictability of words on both EM and ERP measures with reference to current models of eye-movement control during reading. Results are in support of the proposition that lexical access is distributed across several fixations and across brain-electric potentials measured on neighboring words.

  19. Energy Savings Potential and Research, Development, & Demonstration Opportunities for Commercial Building Heating, Ventilation, and Air Conditioning Systems

    SciTech Connect

    none,

    2011-09-01

    This report covers an assessment of 182 different heating, ventilation, and air-conditioning (HVAC) technologies for U.S. commercial buildings to identify and provide analysis on 17 priority technology options in various stages of development. The analyses include an estimation of technical energy-savings potential, description of technical maturity, description of non-energy benefits, description of current barriers for market adoption, and description of the technology’s applicability to different building or HVAC equipment types. From these technology descriptions, are suggestions for potential research, development and demonstration (RD&D) initiatives that would support further development of the priority technology options.

  20. Energy Savings Potential and Research, Development, & Demonstration Opportunities for Residential Building Heating, Ventilation, and Air Conditioning Systems

    SciTech Connect

    Goetzler, William; Zogg, Robert; Young, Jim; Schmidt, Justin

    2012-10-01

    This report is an assessment of 135 different heating, ventilation, and air-conditioning (HVAC) technologies for U.S. residential buildings to identify and provide analysis on 19 priority technology options in various stages of development. The analyses include an estimation of technical energy-savings potential, descriptions of technical maturity, descriptions of non-energy benefits, descriptions of current barriers for market adoption, and descriptions of the technology's applicability to different building or HVAC equipment types. From these technology descriptions, are suggestions for potential research, development and demonstration (RD&D) initiatives that would support further development of the priority technology options.

  1. Ionospheric potential variability in global electric circuit models (Invited)

    NASA Astrophysics Data System (ADS)

    Mareev, E.; Volodin, E. M.; Kalinin, A.; Sllyunyaev, N.

    2013-12-01

    The ionospheric potential (IP) represents the electric voltage between the Earth's surface and the lower ionosphere and may be measured with a sufficient accuracy using the balloon soundings over the lowest 15-20 km. This parameter can serve as a global index relating the state of the global electric circuit (GEC) to the planetary climate. Exploring the GEC as a diagnostic tool for climate studies requires an accurate modeling of the IP stationary state and its dynamics, while a question of secular trend of the IP is still under discussion (Markson, 2007; Williams, 2009; Williams and Mareev, 2013). This paper addresses a possibility of correct calculation of the IP in 3D models of the GEC and its adequate parameterization to be used in General Circulation Models (GCM). Our approach is based on the use the integral representation for the contribution of charging currents, supporting the generators (in particular, electrified clouds) in the GEC, into the ionospheric potential (Kalinin et al., 2011; Mareeva et al., 2011). Simple enough analytical expressions for IP induced by the charging electric currents are suggested, including the contribution of the Austausch generator. We have developed also the spherical numerical model of the GEC and applied it for IP calculation for different-type cloud contribution into the circuit. A suggested IP parameterization is appropriate for the use in climate-model simulations (Mareev and Volodin, 2011). We use a high-resolution GCM of the atmosphere and ocean INMCM4.0 for the modeling the GEC. The main characteristics of the model are: atmosphere - 2x1.5 degrees in longitude and latitude, 21 levels; ocean - 1x0.5 degrees in longitude and latitude, 40 levels. We have taken into account quasi-stationary currents of electrified clouds as principal contributors into the DC global circuit. One of the most important aspects of this approach is an account for all the electrified clouds- both thunderstorms and electrified shower cloud. The

  2. Electric fly swatter: potentially harmful not only for insects?

    PubMed

    Ioannidis, S; Spyropoulou, G A; Pavlidis, L; Dionyssiou, D; Demiri, E

    2014-09-30

    The electric fly-swatter is a household device used widely in Greece to kill mosquitoes. It consists of a racket-shaped electrical screen which is free of toxic and other chemicals. When the screen touches the insects, the contact generates an electric flash of light and the insects are incinerated. We present the case of a 15% flame burn caused by the flash of light produced by an electric fly-swatter. According to our review of the literature, this is the second case of burn injury caused by an electric fly swatter. PMID:26170790

  3. Market analysis, energy savings potential, and future development requirements for Radiance. Final report

    SciTech Connect

    Not Available

    1993-10-01

    The Department of Energy (DOE) Office of Conservation and Renewable Energy (CE), Building Equipment Division has funded the development of a sophisticated computer rendering program called Radiance at Lawrence Berkeley Laboratories (LBL). The project review study included: (1) Surveys of the lighting profession to determine how designers would use an improved, user-friendly Radiance, (2) Elucidation of features, including how Radiance could be used to save energy, which could be incorporated into Radiance to facilitate its more widespread use, (3) Outline of a development plan and determination of what costs the DOE might incur if it were to proceed with the development of an improved version, and (4) Weighing the anticipated development costs against anticipated energy-saving benefits.

  4. An investigation on the fuel savings potential of hybrid hydraulic refuse collection vehicles.

    PubMed

    Bender, Frank A; Bosse, Thomas; Sawodny, Oliver

    2014-09-01

    Refuse trucks play an important role in the waste collection process. Due to their typical driving cycle, these vehicles are characterized by large fuel consumption, which strongly affects the overall waste disposal costs. Hybrid hydraulic refuse vehicles offer an interesting alternative to conventional diesel trucks, because they are able to recuperate, store and reuse braking energy. However, the expected fuel savings can vary strongly depending on the driving cycle and the operational mode. Therefore, in order to assess the possible fuel savings, a typical driving cycle was measured in a conventional vehicle run by the waste authority of the City of Stuttgart, and a dynamical model of the considered vehicle was built up. Based on the measured driving cycle and the vehicle model including the hybrid powertrain components, simulations for both the conventional and the hybrid vehicle were performed. Fuel consumption results that indicate savings of about 20% are presented and analyzed in order to evaluate the benefit of hybrid hydraulic vehicles used for refuse collection.

  5. An investigation on the fuel savings potential of hybrid hydraulic refuse collection vehicles

    SciTech Connect

    Bender, Frank A. Bosse, Thomas; Sawodny, Oliver

    2014-09-15

    Highlights: • Driving cycle acquisition in a refuse collection vehicle. • Vehicle modeling and validation for numerical simulations based on the measured driving cycle. • Fuel consumption analysis for a conventional diesel vehicle and a hybrid hydraulic vehicle. - Abstract: Refuse trucks play an important role in the waste collection process. Due to their typical driving cycle, these vehicles are characterized by large fuel consumption, which strongly affects the overall waste disposal costs. Hybrid hydraulic refuse vehicles offer an interesting alternative to conventional diesel trucks, because they are able to recuperate, store and reuse braking energy. However, the expected fuel savings can vary strongly depending on the driving cycle and the operational mode. Therefore, in order to assess the possible fuel savings, a typical driving cycle was measured in a conventional vehicle run by the waste authority of the City of Stuttgart, and a dynamical model of the considered vehicle was built up. Based on the measured driving cycle and the vehicle model including the hybrid powertrain components, simulations for both the conventional and the hybrid vehicle were performed. Fuel consumption results that indicate savings of about 20% are presented and analyzed in order to evaluate the benefit of hybrid hydraulic vehicles used for refuse collection.

  6. An investigation on the fuel savings potential of hybrid hydraulic refuse collection vehicles.

    PubMed

    Bender, Frank A; Bosse, Thomas; Sawodny, Oliver

    2014-09-01

    Refuse trucks play an important role in the waste collection process. Due to their typical driving cycle, these vehicles are characterized by large fuel consumption, which strongly affects the overall waste disposal costs. Hybrid hydraulic refuse vehicles offer an interesting alternative to conventional diesel trucks, because they are able to recuperate, store and reuse braking energy. However, the expected fuel savings can vary strongly depending on the driving cycle and the operational mode. Therefore, in order to assess the possible fuel savings, a typical driving cycle was measured in a conventional vehicle run by the waste authority of the City of Stuttgart, and a dynamical model of the considered vehicle was built up. Based on the measured driving cycle and the vehicle model including the hybrid powertrain components, simulations for both the conventional and the hybrid vehicle were performed. Fuel consumption results that indicate savings of about 20% are presented and analyzed in order to evaluate the benefit of hybrid hydraulic vehicles used for refuse collection. PMID:24953314

  7. The potential of magneto-electric nanocarriers for drug delivery

    PubMed Central

    Kaushik, Ajeet; Jayant, Rahul Dev; Sagar, Vidya; Nair, Madhavan

    2015-01-01

    Introduction The development and design of personalized nanomedicine for better health quality is receiving great attention. In order to deliver and release a therapeutic concentration at the target site, novel nanocarriers (NCs) were designed, for example, magneto-electric (ME) which possess ideal properties of high drug loading, site-specificity and precise on-demand controlled drug delivery. Areas covered This review explores the potential of ME-NCs for on-demand and site-specific drug delivery and release for personalized therapeutics. The main features including effect of magnetism, improvement in drug loading, drug transport across blood-brain barriers and on-demand controlled release are also discussed. The future directions and possible impacts on upcoming nanomedicine are highlighted. Expert opinion Numerous reports suggest that there is an urgent need to explore novel NC formulations for safe and targeted drug delivery and release at specific disease sites. The challenges of formulation lie in the development of NCs that improve biocompatibility and surface modifications for optimum drug loading/preservation/transmigration and tailoring of electrical–magnetic properties for on-demand drug release. Thus, the development of novel NCs is anticipated to overcome the problems of targeted delivery of therapeutic agents with desired precision that may lead to better patient compliance. PMID:24986772

  8. Electrical properties of sheep Purkinje strands. Electrical and chemical potentials in the clefts.

    PubMed Central

    Levis, R A; Mathias, R T; Eisenberg, R S

    1983-01-01

    The impedence of sheep Purkinje strands, measured to 3-5 kHz, is interpreted with circuit models based on morphology. The strand is described as a one-dimensional electrical cable. Clefts between myocytes of the strand allow radial current to flow in parallel with current across the outer membrane. A lumped model of the clefts, in which all the cleft membrane is in series with 100 omega-cm2, fits only below 20 Hz. Two distributed models, pie and disk, fit at all frequencies with somewhat different (31%) luminal resistivities, but with similar membrane parameters. Series resistance representing the endothelial sheath is small. Simulations of voltage clamp experiments include measured linear parameters and nonlinear membrane channels, as well as radial variation of cleft concentration, membrane flux, voltage, and current. Cleft potential is drastically nonuniform when sodium current flows. Cleft potential is reasonably uniform when calcium and potassium currents flow, but the calcium and potassium concentrations change markedly, enough to turn off the calcium current, even if the calcium channel did not inactivate. We conclude that physiological current flows produce significant nonuniformities in electrochemical potentials in the clefts of this cardiac preparation. PMID:6360228

  9. Geomagnetic storms: Potential economic impacts on electric utilities

    SciTech Connect

    Barnes, P.R.; Van Dyke, J.W.

    1991-03-20

    Geomagnetic storms associated with sunspot and solar flare activity can disturb communications and disrupt electric power. A very severe geomagnetic storm could cause a major blackout with an economic impact of several billion dollars. The vulnerability of electric power systems in the northeast United States will likely increase during the 1990s because of the trend of transmitting large amounts of power over long distance to meet the electricity demands of this region. A comprehensive research program and a warning satellite to monitor the solar wind are needed to enhance the reliability of electric power systems under the influence of geomagnetic storms. 7 refs., 2 figs., 1 tab.

  10. The Boom of Electricity Demand in the Residential Sector in the Developing World and the Potential for Energy Efficiency

    SciTech Connect

    Letschert, Virginie; McNeil, Michael A.

    2008-05-13

    With the emergence of China as the world's largest energy consumer, the awareness of developing country energy consumption has risen. According to common economic scenarios, the rest of the developing world will probably see an economic expansion as well. With this growth will surely come continued rapid growth in energy demand. This paper explores the dynamics of that demand growth for electricity in the residential sector and the realistic potential for coping with it through efficiency. In 2000, only 66% of developing world households had access to electricity. Appliance ownership rates remain low, but with better access to electricity and a higher income one can expect that households will see their electricity consumption rise significantly. This paper forecasts developing country appliance growth using econometric modeling. Products considered explicitly - refrigerators, air conditioners, lighting, washing machines, fans, televisions, stand-by power, water heating and space heating - represent the bulk of household electricity consumption in developing countries. The resulting diffusion model determines the trend and dynamics of demand growth at a level of detail not accessible by models of a more aggregate nature. In addition, the paper presents scenarios for reducing residential consumption through cost-effective and/or best practice efficiency measures defined at the product level. The research takes advantage of an analytical framework developed by LBNL (BUENAS) which integrates end use technology parameters into demand forecasting and stock accounting to produce detailed efficiency scenarios, which allows for a realistic assessment of efficiency opportunities at the national or regional level. The past decades have seen some of the developing world moving towards a standard of living previously reserved for industrialized countries. Rapid economic development, combined with large populations has led to first China and now India to emerging as 'energy

  11. ENERGY SAVINGS POTENTIALS IN RESIDENTIAL AND SMALL COMMERCIAL THERMAL DISTRIBUTION SYSTEMS - AN UPDATE

    SciTech Connect

    ANDREWS,J.W.

    2003-10-31

    This is an update of a report (Andrews and Modera 1991) that quantified the amounts of energy that could be saved through better thermal distribution systems in residential and small commercial buildings. Thermal distribution systems are the ductwork, piping, or other means used to transport heat or cooling from the space-conditioning equipment to the conditioned space. This update involves no basic change in methodology relative to the 1991 report, but rather a review of the additional information available in 2003 on the energy-use patterns in residential and small commercial buildings.

  12. Review of Innovative Energy Savings Technology for the Electric Arc Furnace

    NASA Astrophysics Data System (ADS)

    Lee, Baek; Sohn, Il

    2014-09-01

    A review of the energy innovations for the electric arc furnace (EAF) steelmaking route is discussed. Preheating of scrap using vertical and horizontal shafts that have been commercially successful in lowering the energy consumption to as much as 90 kWh/t reaching almost the operational limit to heating input scrap materials into the EAF is discussed. Bucket-type and twin-shell preheaters have also shown to be effective in lowering the overall power consumption by 60 kWh/t, but these have been less effective than the vertical shaft-type preheaters. Beyond the scrap preheating technologies, the utilization of waste heat of the slags from the laboratory scale to the pilot scale has shown possible implementation of a granulation and subsequent heat exchange with forced air for energy recovery from the hot slags. Novel techniques to increase metal recovery have shown that laboratory-scale testing of localized Fe concentration into the primary spinel crystals was possible allowing the separation of an Fe-rich crystal from an Fe-depleted amorphous phase. A possible future process for converting the thermal energy of the CO/CO2 off-gases from the EAF into chemical energy was introduced.

  13. Weyerhaeuser Company: Longview Mill Conducts Energy and Water Assessment that Finds Potential for $3.1 Million in Annual Savings

    SciTech Connect

    Not Available

    2004-06-01

    Weyerhaeuser completed a plant-wide energy assessment at its pulp and paper manufacturing facility in Longview, Washington, in 2002. The assessment identified nine projects for improving energy efficiency and reducing water consumption. Implementing these projects will save an estimated $3.1 million annually in natural gas costs. These measures will also reduce site water consumption by 3,600 gallons per minute. The estimated cost of these improvements is estimated at $5 million to $11 million. Aside from the nine projects discussed above, the assessment team also identified the potential to increase onsite power generation by up to 15 megawatts.

  14. [Effects of labor-saving rice cultivation modes on the diversity of potential weed communities in paddy fields].

    PubMed

    Li, Shu-Shun; Qiang, Sheng; Jiao, Jun-Sen

    2009-10-01

    Aimed to understand the effects of various labor-saving rice cultivation modes on the diversity of potential weed communities in paddy fields, an investigation was made on the quantitative characteristics of the weed seed bank under dry direct seeding, water direct seeding, seedling throwing, mechanized-transplanting, wheat-rice interplanting, and conventional manual transplanting. Under dry direct seeding, the density of the weed seed bank was up to 228,416 seeds x m(-2), being significantly higher than that under the other five cultivation modes. Wheat-rice interplanting ranked the second place. The seed density of sedge weeds under dry direct seeding and that of broad leaf weeds under wheat-rice interplanting were significantly higher than the seed densities of various kinds of weeds under other cultivation modes. Conventional manual transplanting mode had the highest species richness, with Margalef index being 1.86. The diversity indices, including Shannon-Wiener index, Gini index, and Pielou evenness index under water direct seeding and wheat-rice interplanting were higher than those under other cultivation modes. Comparing with conventional manual transplanting mode, the other five cultivation modes had their own dominant species in the potential weed community, and thereby, different labor-saving rice cultivation modes should be applied by turns to control the potential weed community in paddy fields effectively and persistently.

  15. Impacts of residence time during storage on potential of water saving for grey water recycling system.

    PubMed

    Liu, S; Butler, D; Memon, F A; Makropoulos, C; Avery, L; Jefferson, B

    2010-01-01

    Grey water recycling has been generally accepted and is about to move into practice in terms of sustainable development. Previous research has revealed the bacteria re-growth in grey water and reclaimed municipal water during storage. However, in most present grey water recycling practices, impacts of water quality changes during storage on the system's performance and design regulation have not been addressed. In this paper, performance of a constructed wetland based grey water recycling system was analysed by taking the constraint of residence time during storage into account using an object based household water cycle model. Two indicators, water saving efficiency (WSE) and residence time index (RTI), are employed to reflect the system's performance and residence time during storage respectively. Results show that WSE and RTI change with storage tank volumes oppositely. As both high WSE and RTI cannot be achieved simultaneously, it is concluded that in order to achieve the most cost-effective and safe solution, systems with both small grey and green tanks are needed, whilst accepting that only relatively modest water saving efficiency targets can be achieved. Higher efficiencies will only be practicable if water quality deterioration in the green water tank can be prevented by some means (e.g. disinfection).

  16. Lighting energy savings potential of split-pane electrochromic windows controlled for daylighting with visual comfort

    SciTech Connect

    Software, Anyhere; Fernandes, Luis; Lee, Eleanor; Ward, Greg

    2013-03-15

    A simulation study was conducted to evaluate lighting energy savings of split-pane electrochromic (EC) windows controlled to satisfy key visual comfort parameters. Using the Radiance lighting simulation software, interior illuminance and luminance levels were computed for a south-facing private office illuminated by a window split into two independently-controlled EC panes. The transmittance of these was optimized hourly for a workplane illuminance target while meeting visual comfort constraints, using a least-squares algorithm with linear inequality constraints. Blinds were successively deployed until visual comfort criteria were satisfied. The energy performance of electrochromics proved to be highly dependent on how blinds were controlled. With hourly blind position adjustments, electrochromics showed significantly higher (62percent and 53percent, respectively without and with overhang) lighting energy consumption than clear glass. With a control algorithm designed to better approximate realistic manual control by an occupant, electrochromics achieved significant savings (48percent and 37percent, respectively without and with overhang). In all cases, energy consumption decreased when the workplace illuminance target was increased. In addition, the fraction of time during which the occupant had an unobstructed view of the outside was significantly greater with electrochromics: 10 months out of the year versus a handful of days for the reference case.

  17. Estimation of the electrical potential distribution along metallic casing from surface self-potential profile

    NASA Astrophysics Data System (ADS)

    Maineult, Alexis

    2016-06-01

    Corroding casings of wells generate negative self-potential (SP) anomalies, increasing from about - 10 to - 500 mV in the vicinity of the well to 0 mV at large distances. As reported in previous laboratory experiment, SP can be used to retrieve the distribution of electrical potential along the casing, which is somehow a proxy for the corrosion state of the casing. These studies used 3D (whole space) or surface 2D (whole surface) measurements of SP distribution; here we reported a field example, for which only a 1D surface SP profile is available. In order to retrieve the most probable associated potential distribution (defined by a spline) along the 11.1-m long metallic casing, we develop a direct model based on geometrical and geoelectrical properties of the medium, which was then used in a (non-deterministic) optimization procedure by simulated annealing, including some physical constrains. Tests carried out on a synthetic case allowed the initial source to be correctly retrieved, provided that the number of nodes used for the spline defining the potential distribution along the casing is large enough. The inversion of real field data provided a dipolar anomaly, with minimal negative amplitude of around - 600 mV at 5 m, and maximal positive amplitude of about 1100 mV at 9 m (close to the level of the water table), this shape being in agreement with the results of previous laboratory studies.

  18. Inhibition Potentiates the Synchronizing Action of Electrical Synapses

    PubMed Central

    Pfeuty, Benjamin; Golomb, David; Mato, Germán; Hansel, David

    2007-01-01

    In vivo and in vitro experimental studies have found that blocking electrical interactions connecting GABAergic interneurons reduces oscillatory activity in the γ range in cortex. However, recent theoretical works have shown that the ability of electrical synapses to promote or impede synchrony, when alone, depends on their location on the dendritic tree of the neurons, the intrinsic properties of the neurons and the connectivity of the network. The goal of the present paper is to show that this versatility in the synchronizing ability of electrical synapses is greatly reduced when the neurons also interact via inhibition. To this end, we study a model network comprising two-compartment conductance-based neurons interacting with both types of synapses. We investigate the effect of electrical synapses on the dynamical state of the network as a function of the strength of the inhibition. We find that for weak inhibition, electrical synapses reinforce inhibition-generated synchrony only if they promote synchrony when they are alone. In contrast, when inhibition is sufficiently strong, electrical synapses improve synchrony even if when acting alone they would stabilize asynchronous firing. We clarify the mechanism underlying this cooperative interplay between electrical and inhibitory synapses. We show that it is relevant in two physiologically observed regimes: spike-to-spike synchrony, where neurons fire at almost every cycle of the population oscillations, and stochastic synchrony, where neurons fire irregularly and at a rate which is substantially lower than the frequency of the global population rhythm. PMID:18946530

  19. Effect of low electrical potentials on the microhardness of metallic materials

    NASA Astrophysics Data System (ADS)

    Orlova, D. V.; Danilov, V. I.; Zuev, L. B.; Staskevich, O. S.

    2016-01-01

    The effect of low (<5 V) electrical potentials on the microhardness of metallic materials has been studied experimentally. It has been revealed that this effect does depend on the sign of the electric field potential. It has been found that the microhardness of aluminum, cobalt, and zinc decreases and the microhardness of zirconium and iron increases when an electrical potential is applied. It has been argued that the degree of microhardness change under an electric field depends on the magnitude of applied potential, the magnitude of the Hall coefficient of a metal, and its physicochemical properties.

  20. Energy efficiency monitoring and economic analysis for energy saving potential in UNITEN

    NASA Astrophysics Data System (ADS)

    Reyasudin Basir Khan, M.; Jidin, Razali; Pasupuleti, Jagadeesh; Yew, Kang Chin; Azwa Shaaya, Sharifah

    2013-06-01

    This paper discusses on energy efficiency survey for typical buildings in Universiti Tenaga Nasional (UNITEN). Undeniably, wastage of energy will cause the increase of operation cost and depletion of fossil fuel resources which contributes to the climate change issue in the world. UNITEN was commenced in the late 1990s and most of the buildings in this university are not equipped with energy management system. Such system is the solution to reduce energy use while maximizing the comfort levels of the occupants. Disregard to the energy management system, the implementation of other energy saving measures is the main objective of this paper. By taking the right measures, the energy wastage in the buildings of this university can be reduced.

  1. The Potential of Combined Heat and Power Generation, Wind Power Generation and Load Management Techniques for Cost Reduction in Small Electricity Supply Systems.

    NASA Astrophysics Data System (ADS)

    Bass, Jeremy Hugh

    Available from UMI in association with The British Library. Requires signed TDF. An evaluation is made of the potential fuel and financial savings possible when a small, autonomous diesel system sized to meet the demands of an individual, domestic consumer is adapted to include: (1) combined heat and power (CHP) generation, (2) wind turbine generation, (3) direct load control. The potential of these three areas is investigated by means of time-step simulation modelling on a microcomputer. Models are used to evaluate performance and a Net Present Value analysis used to assess costs. A cost/benefit analysis then enables those areas, or combination of areas, that facilitate and greatest savings to be identified. The modelling work is supported by experience gained from the following: (1) field study of the Lundy Island wind/diesel system, (2) laboratory testing of a small diesel generator set, (3) study of a diesel based CHP unit, (4) study of a diesel based direct load control system, (5) statistical analysis of data obtained from the long-term monitoring of a large number of individual household's electricity consumption. Rather than consider the consumer's electrical demand in isolation, a more flexible approach is adopted, with consumer demand being regarded as the sum of primarily two components: a small, electricity demand for essential services and a large, reschedulable demand for heating/cooling. The results of the study indicate that: (1) operating a diesel set in a CHP mode is the best strategy for both financial and fuel savings. A simple retrofit enables overall conversion efficiencies to be increased from 25% to 60%, or greater, at little cost. (2) wind turbine generation in association with direct load control is a most effective combination. (3) a combination of both the above areas enables greatest overall financial savings, in favourable winds resulting in unit energy costs around 20% of those of diesel only operation.

  2. CNQX and AMPA inhibit electrical synaptic transmission: a potential interaction between electrical and glutamatergic synapses

    PubMed Central

    Li, Qin; Burrell, Brian D.

    2008-01-01

    Electrical synapses play an important role in signaling between neurons and the synaptic connections between many neurons possess both electrical and chemical components. Although modulation of electrical synapses is frequently observed, the cellular processes that mediate such changes have not been studied as thoroughly as plasticity in chemical synapses. In the leech (Hirudo sp), the competitive AMPA receptor antagonist CNQX inhibited transmission at the rectifying electrical synapse of a mixed glutamatergic/electrical synaptic connection. This CNQX-mediated inhibition of the electrical synapse was blocked by concanavalin A (Con A) and dynamin inhibitory peptide (DIP), both of which are known to inhibit endocytosis of neurotransmitter receptors. CNQX-mediated inhibition was also blocked by pep2-SVKI (SVKI), a synthetic peptide that prevents internalization of AMPA-type glutamate receptor. AMPA itself also inhibited electrical synaptic transmission and this AMPA-mediated inhibition was partially blocked by Con A, DIP and SVKI. Low frequency stimulation induced long-term depression (LTD) in both the electrical and chemical components of these synapses and this LTD was blocked by SVKI. GYKI 52466, a selective non-competitive antagonist of AMPA receptors, did not affect the electrical EPSP, although it did block the chemical component of these synapses. CNQX did not affect non-rectifying electrical synapses in two different pairs of neurons. These results suggest an interaction between AMPA-type glutamate receptors and the gap junction proteins that mediate electrical synaptic transmission. This putative interaction between glutamate receptors and gap junction proteins represents a novel mechanism for regulating the strength of synaptic transmission. PMID:18601913

  3. Saving Water Saves Energy

    SciTech Connect

    McMahon, James E.; Whitehead, Camilla Dunham; Biermayer, Peter

    2006-06-15

    Hot water use in households, for showers and baths as wellas for washing clothes and dishes, is a major driver of household energyconsumption. Other household uses of water (such as irrigatinglandscaping) require additional energy in other sectors to transport andtreat the water before use, and to treat wastewater. In California, 19percent of total electricity for all sectors combined and 32 percent ofnatural gas consumption is related to water. There is a criticalinterdependence between energy and water systems: thermal power plantsrequire cooling water, and water pumping and treatment require energy.Energy efficiency can be increased by a number of means, includingmore-efficient appliances (e.g., clothes washers or dishwashers that useless total water and less heated water), water-conserving plumbingfixtures and fittings (e.g., showerheads, faucets, toilets) and changesin consumer behavior (e.g., lower temperature set points for storagewater heaters, shorter showers). Water- and energy-conserving activitiescan help offset the stress imposed on limited water (and energy) suppliesfrom increasing population in some areas, particularly in drought years,or increased consumption (e.g., some new shower systems) as a result ofincreased wealth. This paper explores the connections between householdwater use and energy, and suggests options for increased efficiencies inboth individual technologies and systems. Studies indicate that urbanwater use can be reduced cost-effectively by up to 30 percent withcommercially available products. The energy savings associated with watersavings may represent a large additional and largely untappedcost-effective opportunity.

  4. Electrical Potential Transfer Through Grounding and the Concern for Facility and Worker Safety

    SciTech Connect

    Konkel, Herbert

    1998-09-13

    Electrical grounding is probably the most over-looke~ ignored, and misunderstood part of electrical energy source circuits. A faulty ground circuit am have lethal potential to the worker, can damage electrical equipment" or components, and can lead to higher consequences. For example, if the green-wire ground return circuit (in a three-wire power circuit) is fhulty or is open (someone cut the prong, etc.) a person can receive an electrical shock by touching the conductive enclosure, and the result can be lethal. If high explosives are involved m the process, sneak electrical energy paths may cause electrical threats that lead to ignition, which results to higher damage consequences. Proper electrical grounding is essential to mitigate the electrical hazard and improve work place safety. A designer must ask the question, "What grounding is proper?" continuously through a process design and in its application. This question must be readdressed with any process change, including tiom layout, equipment, or procedure changes. Electrical grounding varies ilom local work area grounding to the multi-point grounding found in large industrial areas. These grounding methods become more complex when the designer adds bonding to the grounding schemes to mitigate electrostatic discharge (ESD) and surfkce potentials resulting from lightning currents flowing through the facility structure. Figure 1 shows a typical facility power distribution circuit and the current flow paths resulting ffom a lightning discharge to a facility. This paper discusses electrical grounding methods and their characteristics and identifies potential sneak paths into a process for hazardous electrical energy.

  5. Assessment of Energy Savings Potential from the Use of Demand Control Ventilation Systems in General Office Spaces in California

    SciTech Connect

    Hong, Tianzhen; Fisk, William J.

    2009-07-08

    Demand controlled ventilation (DCV) was evaluated for general office spaces in California. A medium size office building meeting the prescriptive requirements of the 2008 California building energy efficiency standards (CEC 2008) was assumed in the building energy simulations performed with the EnergyPlus program to calculate the DCV energy savings potential in five typical California climates. Three design occupancy densities and two minimum ventilation rates were used as model inputs to cover a broader range of design variations. The assumed values of minimum ventilation rates in offices without DCV, based on two different measurement methods, were 81 and 28 cfm per occupant. These rates are based on the co-author's unpublished analyses of data from EPA's survey of 100 U.S. office buildings. These minimum ventilation rates exceed the 15 to 20 cfm per person required in most ventilation standards for offices. The cost effectiveness of applying DCV in general office spaces was estimated via a life cycle cost analyses that considered system costs and energy cost reductions. The results of the energy modeling indicate that the energy savings potential of DCV is largest in the desert area of California (climate zone 14), followed by Mountains (climate zone 16), Central Valley (climate zone 12), North Coast (climate zone 3), and South Coast (climate zone 6). The results of the life cycle cost analysis show DCV is cost effective for office spaces if the typical minimum ventilation rates without DCV is 81 cfm per person, except at the low design occupancy of 10 people per 1000 ft{sup 2} in climate zones 3 and 6. At the low design occupancy of 10 people per 1000 ft{sup 2}, the greatest DCV life cycle cost savings is a net present value (NPV) of $0.52/ft{sup 2} in climate zone 14, followed by $0.32/ft{sup 2} in climate zone 16 and $0.19/ft{sup 2} in climate zone 12. At the medium design occupancy of 15 people per 1000 ft{sup 2}, the DCV savings are higher with a NPV $0

  6. Membrane potential perturbations induced in tissue cells by pulsed electric fields

    SciTech Connect

    Cooper, M.S.

    1995-09-01

    Pulsed electric fields directly influence the electrophysiology of tissue cells by transiently perturbing their transmembrane potential. To determine the magnitude and time course of this interaction, electronic cable theory was used to calculate the membrane potential perturbations induced in tissue cells by a spatially uniform, pulsed electric field. Analytic solutions were obtained that predict shifts in membrane potential along the length of cells as a function of time in response to an electrical pulse. For elongated tissue cells, or groups of tissue cells that are couple electronically by gap junctions, significant hyperpolarizations and depolarizations can result form millisecond applications of electric fields with strengths on the order of 10--100 mV/cm. The results illustrate the importance of considering cellular cable parameters in assessing the effects of transient electric fields on biological systems, as well as in predicting the efficacy of pulsed electric fields in medical treatments.

  7. Small hydro-electric potential: West Poverty Bay region

    NASA Astrophysics Data System (ADS)

    1981-07-01

    Six schemes in the Bay of Plenty Electric Power Board area and two in the Poverty Bay Electric Power Board area, of which five and one, respectively are below the economic limit of $2400/kW were identified. Only three appear both economically and environmentally acceptable. The schemes identified are not very attractive on the national scale and could not be justified on local terms. It is recommended that a detailed feasibility study of the Takaputahi/Torere diversion is undertaken prior to a decision making to proceed with the Motu development, or if the proposals are dropped. The present low load and slow growth of the area is such that prior to a small hydroelectric scheme is built, demand for power has to be established.

  8. The potential of plug-in hybrid electric vehicles to reduce petroleum use issues involved in developing reliable estimates.

    SciTech Connect

    Vyas, A. D.; Santini, D. J.; Johnson, L. R.; Energy Systems

    2009-01-01

    This paper delineates the various issues involved in developing reliable estimates of the petroleum use reduction that would result from the wide-spread introduction of plug-in hybrid electric vehicles (PHEVs). Travel day data from the 2001 National Household Travel Survey (NHTS) were analyzed to identify the share of vehicle miles of travel (VMT) that could be transferred to grid electricity. Various PHEV charge-depleting (CD) ranges were evaluated, and 100% CD mode and potential blended modes were analyzed. The NHTS data were also examined to evaluate the potential for PHEV battery charging multiple times a day. Data from the 2005 American Housing Survey (AHS) were analyzed to evaluate the availability of garages and carports for at-home charging of the PHEV battery. The AHS data were also reviewed by census region and household location within or outside metropolitan statistical areas. To illustrate the lag times involved, the historical new vehicle market share increases for the diesel power train in France (a highly successful case) and the emerging hybrid electric vehicles in the United States were examined. A new vehicle technology substitution model is applied to illustrate a historically plausible successful new PHEV market share expansion. The trends in U.S. light-duty vehicle sales and light-duty vehicle stock were evaluated to estimate the time required for hypothetical successful new PHEVs to achieve the ultimately attainable share of the existing vehicle stock. Only when such steps have been accomplished will the full oil savings potential for the nation be achieved.

  9. Methods for detecting and locating leaks in containment facilities using electrical potential data and electrical resistance tomographic imaging techniques

    DOEpatents

    Daily, William D.; Laine, Daren L.; Laine, Edwin F.

    2001-01-01

    Methods are provided for detecting and locating leaks in liners used as barriers in the construction of landfills, surface impoundments, water reservoirs, tanks, and the like. Electrodes are placed in the ground around the periphery of the facility, in the leak detection zone located between two liners if present, and/or within the containment facility. Electrical resistivity data is collected using these electrodes. This data is used to map the electrical resistivity distribution beneath the containment liner or between two liners in a double-lined facility. In an alternative embodiment, an electrode placed within the lined facility is driven to an electrical potential with respect to another electrode placed at a distance from the lined facility (mise-a-la-masse). Voltage differences are then measured between various combinations of additional electrodes placed in the soil on the periphery of the facility, the leak detection zone, or within the facility. A leak of liquid through the liner material will result in an electrical potential distribution that can be measured at the electrodes. The leak position is located by determining the coordinates of an electrical current source pole that best fits the measured potentials with the constraints of the known or assumed resistivity distribution.

  10. Methods for detecting and locating leaks in containment facilities using electrical potential data and electrical resistance tomographic imaging techniques

    DOEpatents

    Daily, W.D.; Laine, D.L.; Laine, E.F.

    1997-08-26

    Methods are provided for detecting and locating leaks in liners used as barriers in the construction of landfills, surface impoundments, water reservoirs, tanks, and the like. Electrodes are placed in the ground around the periphery of the facility, in the leak detection zone located between two liners if present, and/or within the containment facility. Electrical resistivity data is collected using these electrodes. This data is used to map the electrical resistivity distribution beneath the containment liner between two liners in a double-lined facility. In an alternative embodiment, an electrode placed within the lined facility is driven to an electrical potential with respect to another electrode placed at a distance from the lined facility (mise-a-la-masse). Voltage differences are then measured between various combinations of additional electrodes placed in the soil on the periphery of the facility, the leak detection zone, or within the facility. A leak of liquid though the liner material will result in an electrical potential distribution that can be measured at the electrodes. The leak position is located by determining the coordinates of an electrical current source pole that best fits the measured potentials with the constraints of the known or assumed resistivity distribution. 6 figs.

  11. Methods for detecting and locating leaks in containment facilities using electrical potential data and electrical resistance tomographic imaging techniques

    DOEpatents

    Daily, William D.; Laine, Daren L.; Laine, Edwin F.

    1997-01-01

    Methods are provided for detecting and locating leaks in liners used as barriers in the construction of landfills, surface impoundments, water reservoirs, tanks, and the like. Electrodes are placed in the ground around the periphery of the facility, in the leak detection zone located between two liners if present, and/or within the containment facility. Electrical resistivity data is collected using these electrodes. This data is used to map the electrical resistivity distribution beneath the containment liner between two liners in a double-lined facility. In an alternative embodiment, an electrode placed within the lined facility is driven to an electrical potential with respect to another electrode placed at a distance from the lined facility (mise-a-la-masse). Voltage differences are then measured between various combinations of additional electrodes placed in the soil on the periphery of the facility, the leak detection zone, or within the facility. A leak of liquid though the liner material will result in an electrical potential distribution that can be measured at the electrodes. The leak position is located by determining the coordinates of an electrical current source pole that best fits the measured potentials with the constraints of the known or assumed resistivity distribution.

  12. Mapping of electrical potential distributions with charged particle beams

    NASA Technical Reports Server (NTRS)

    Robinson, J. W.

    1982-01-01

    Methods for measuring electrostatic potentials on and near dielectric surfaces charged to several kilovolts are studied. Secondary emission from those charged dielectrics is measured. Candidates for potential measurement include the induced charge, from which potential is calculated; the trajectory endpoints of either high or low energy particles traversing the region near the surface; trajectory impact on the surface; and creating ions at points of interest near the surface. Some of the methods require computer simulations and iterative calculation if potential maps are to be generated. Several approaches are described and compared. A method using a half-cylinder as a test chamber and low-energy probing beams is adapted for the measurement of seconary emission.

  13. Short latency vestibular potentials evoked by electrical round window stimulation in the guinea pig.

    PubMed

    Bordure, P; Desmadryl, G; Uziel, A; Sans, A

    1989-11-01

    Short-latency potentials evoked by round window electrical stimulation were recorded in guinea pig by means of vertex-pinna skin electrodes using averaging techniques. Constant current shocks of 20 microseconds or 50 microseconds (25-300 microA) were used to evoke both auditory and vestibular brain-stem potentials. Pure auditory potentials, comparable to those evoked by acoustic clicks, were obtained by 20 microseconds electrical stimuli and disappeared during an auditory masking procedure made with a continuous white noise (110 dB SPL). Short latency potentials labeled V1, V2 and V3 were obtained by 50 microseconds electrical stimuli during an auditory masking procedure. This response disappeared after specific vestibular neurectomy, whereas the auditory response evoked by acoustic clicks or by electrical stimulation remained unchanged, suggesting that these latter potentials had a vestibular origin.

  14. Short latency vestibular potentials evoked by electrical round window stimulation in the guinea pig.

    PubMed

    Bordure, P; Desmadryl, G; Uziel, A; Sans, A

    1989-11-01

    Short-latency potentials evoked by round window electrical stimulation were recorded in guinea pig by means of vertex-pinna skin electrodes using averaging techniques. Constant current shocks of 20 microseconds or 50 microseconds (25-300 microA) were used to evoke both auditory and vestibular brain-stem potentials. Pure auditory potentials, comparable to those evoked by acoustic clicks, were obtained by 20 microseconds electrical stimuli and disappeared during an auditory masking procedure made with a continuous white noise (110 dB SPL). Short latency potentials labeled V1, V2 and V3 were obtained by 50 microseconds electrical stimuli during an auditory masking procedure. This response disappeared after specific vestibular neurectomy, whereas the auditory response evoked by acoustic clicks or by electrical stimulation remained unchanged, suggesting that these latter potentials had a vestibular origin. PMID:2479525

  15. Electrical potentials in bone induced by ultrasound irradiation in the megahertz range

    NASA Astrophysics Data System (ADS)

    Okino, M.; Coutelou, S.; Mizuno, K.; Yanagitani, T.; Matsukawa, M.

    2013-09-01

    Low frequency mechanical studies have reported the contribution of stress-induced electrical potentials to bone metabolism. However, the healing mechanism of bone fractures by low intensity ultrasound is not yet clear. We demonstrate that bone can generate electrical potentials by ultrasound irradiation in the MHz range. Electrical potentials were obtained from the output of bovine cortical bone transducers. In the range of 0.7-2.5 MHz, sensitivities of bone transducers were around 1/1000 of a poly (vinylidene fluoride) ultrasonic transducer and did not depend on magnitude and alignment of hydroxyapatite crystallites in bone.

  16. A comparison of potential electric propulsion systems for orbit transfer

    NASA Technical Reports Server (NTRS)

    Jones, R. M.

    1982-01-01

    Electric propulsion concepts are compared on the basis of trip time for the low earth orbit (LEO) to geosynchronous earth orbit (GEO) mission. Resistojet, arcjet, magnetoplasmadynamic (MPD), pulsed inductive, and ion engine thruster concepts are included. The optimum (minimum trip time) value of specific impulse is found to be dependent upon the specific mission and system being considered. As expected, the devices which can deliver good efficiency at low specific impulses promise the fastest trip times. The solution for trip time and propellant mass for the constant power, continuous low acceleration orbit transfer problem (one way and round trip) is presented in nomograph form. The influences of mission Delta V, thruster efficiency, specific impulse, power, power and propulsion system mass, and payload mass are clearly illustrated.

  17. Potential emission savings from refrigeration and air conditioning systems by using low GWP refrigerants

    DOE PAGES

    Beshr, Mohamed; Aute, Vikrant; Abdelaziz, Omar; Fricke, Brian; Radermacher, Reinhard

    2016-08-24

    Refrigeration and air conditioning systems have high, negative environmental impacts due to refrigerant charge leaks from the system and their corresponding high global warming potential. Thus, many efforts are in progress to obtain suitable low GWP alternative refrigerants and more environmentally friendly systems for the future. In addition, the system’s life cycle climate performance (LCCP) is a widespread metric proposed for the evaluation of the system’s environmental impact.

  18. Electric Mars: The first direct measurement of an upper limit for the Martian "polar wind" electric potential

    NASA Astrophysics Data System (ADS)

    Collinson, Glyn; Mitchell, David; Glocer, Alex; Grebowsky, Joseph; Peterson, W. K.; Connerney, Jack; Andersson, Laila; Espley, Jared; Mazelle, Christian; Sauvaud, Jean-André; Fedorov, Andrei; Ma, Yingjuan; Bougher, Steven; Lillis, Robert; Ergun, Robert; Jakosky, Bruce

    2015-11-01

    An important mechanism in the generation of polar wind outflow is the ambipolar electric potential which assists ions in overcoming gravity and is a key mechanism for Terrestrial ionospheric escape. At Mars, open field lines are not confined to the poles, and outflow of ionospheric electrons is observed far into the tail. It has thus been hypothesized that a similar electric potential may be present at Mars, contributing to global ionospheric loss. However, no direct measurements of this potential have been made. In this pilot study, we examine photoelectron spectra measured by the Solar Wind Electron Analyzer instrument on the NASA Mars Atmosphere and Volatile EvolutioN (MAVEN) Mars Scout to put an initial upper bound on the total potential drop in the ionosphere of Mars of Φ♂ ≾⊥ 2V , with the possibility of a further ≾4.5 V potential drop above this in the magnetotail. If the total potential drop was close to the upper limit, then strong outflows of major ionospheric species (H+, O+, and O2+) would be expected. However, if most of the potential drop is confined below the spacecraft, as expected by current theory, then such a potential would not be sufficient on its own to accelerate O2+ to escape velocities, but would be sufficient for lighter ions. However, any potential would contribute to atmospheric loss through the enhancement of Jeans escape.

  19. Plug-in hybrid electric vehicles : How does one determine their potential for reducing U.S. oil dependence?

    SciTech Connect

    Vyas, A.; Santini, D.; Duoba, M.; Alexander, M.; Energy Systems; EPRI

    2008-09-01

    Estimation of the potential of plug-in hybrid electric vehicles (PHEV's) ability to reduce U.S. gasoline use is difficult and complex. Although techniques have been proposed to estimate the vehicle kilometers of travel (VKT) that can be electrified, these methods may be inadequate and/or inappropriate for early market introduction circumstances. Factors that must be considered with respect to the PHEV itself include (1) kWh battery storage capability; (2) kWh/km depletion rate of the vehicle (3) liters/km use of gasoline (4) average daily kilometers driven (5) annual share of trips exceeding the battery depletion distance (6) driving cycle(s) (7) charger location [i.e. on-board or off-board] (8) charging rate. Each of these factors is actually a variable, and many interact. Off the vehicle, considerations include (a) primary overnight charging spot [garage, carport, parking garage or lot, on street], (b) availability of primary and secondary charging locations [i.e. dwellings, workplaces, stores, etc] (c) time of day electric rates (d) seasonal electric rates (e) types of streets and highways typically traversed during most probable trips depleting battery charge [i.e. city, suburban, rural and high vs. low density]; (f) cumulative trips per day from charger origin (g) top speeds and peak acceleration rates required to make usual trips. Taking into account PHEV design trade-off possibilities (kW vs. kWh of battery, in particular), this paper attempts to extract useful information relating to these topics from the 2001 National Household Travel Survey (NHTS), and the 2005 American Housing Survey (AHS). Costs per kWh of PHEVs capable of charge depleting (CD) all-electric range (CDE, or AER) vs. those CD in 'blended' mode (CDB) are examined. Lifetime fuel savings of alternative PHEV operating/utilization strategies are compared to battery cost estimates.

  20. Potential Benefits from Improved Energy Efficiency of KeyElectrical Products: The Case of India

    SciTech Connect

    McNeil, Michael; Iyer, Maithili; Meyers, Stephen; Letschert,Virginie; McMahon, James E.

    2005-12-20

    The goal of this project was to estimate the net benefits that cost-effective improvements in energy efficiency can bring to developing countries. The study focused on four major electrical products in the world's second largest developing country, India. These products--refrigerators, room air conditioners, electric motors, and distribution transformers--are important targets for efficiency improvement in India and in other developing countries. India is an interesting subject of study because of it's size and rapid economic growth. Implementation of efficient technologies in India would save billions in energy costs, and avoid hundreds of megatons of greenhouse gas emissions. India also serves as an example of the kinds of improvement opportunities that could be pursued in other developing countries.

  1. Correlation of ISS Electric Potential Variations with Mission Operations

    NASA Technical Reports Server (NTRS)

    Willis, Emily M.; Minow, Joseph I.; Parker, Linda Neergaard

    2014-01-01

    Orbiting approximately 400 km above the Earth, the International Space Station (ISS) is a unique research laboratory used to conduct ground-breaking science experiments in space. The ISS has eight Solar Array Wings (SAW), and each wing is 11.7 meters wide and 35.1 meters long. The SAWs are controlled individually to maximize power output, minimize stress to the ISS structure, and minimize interference with other ISS operations such as vehicle dockings and Extra-Vehicular Activities (EVA). The Solar Arrays are designed to operate at 160 Volts. These large, high power solar arrays are negatively grounded to the ISS and collect charged particles (predominately electrons) as they travel through the space plasma in the Earth's ionosphere. If not controlled, this collected charge causes floating potential variations which can result in arcing, causing injury to the crew during an EVA or damage to hardware [1]. The environmental catalysts for ISS floating potential variations include plasma density and temperature fluctuations and magnetic induction from the Earth's magnetic field. These alone are not enough to cause concern for ISS, but when they are coupled with the large positive potential on the solar arrays, floating potentials up to negative 95 Volts have been observed. Our goal is to differentiate the operationally induced fluctuations in floating potentials from the environmental causes. Differentiating will help to determine what charging can be controlled, and we can then design the proper operations controls for charge collection mitigation. Additionally, the knowledge of how high power solar arrays interact with the environment and what regulations or design techniques can be employed to minimize charging impacts can be applied to future programs.

  2. Functions and potential applications of glycolipid biosurfactants--from energy-saving materials to gene delivery carriers.

    PubMed

    Kitamoto, Dai; Isoda, Hiroko; Nakahara, Tadaatsu

    2002-01-01

    Biosurfactants (BS) produced by various microorganisms show unique properties (e.g., mild production conditions, lower toxicity, higher biodegradability and environmental compatibility) compared to their chemical counterparts. The numerous advantages of BS have prompted applications not only in the food, cosmetic, and pharmaceutical industries but in environmental protection and energy-saving technology as well. Glycolipid BS are the most promising, due to high productivity from renewable resources and versatile biochemical properties. Mannosylerythritol lipids (MEL), which are glycolipid BS produced by a yeast Candida antarctrica, exhibit not only excellent interfacial properties but also remarkable differentiation-inducing activities against human leukemia cells. MEL also show a potential anti-agglomeration effect on ice particles in ice slurry used for cold thermal storage. Recently, the cationic liposome bearing MEL has been demonstrated to increase dramatically the efficiency of gene transfection into mammalian cells. These features of BS should broaden its applications in new advanced technologies. The current status of research and development on glycolipid BS, especially their function and potential applications, is discussed. PMID:16233292

  3. Remote detection of human electroencephalograms using ultrahigh input impedance electric potential sensors

    NASA Astrophysics Data System (ADS)

    Harland, C. J.; Clark, T. D.; Prance, R. J.

    2002-10-01

    In this letter, we demonstrate the use of very high performance, ultrahigh impedance, electric potential probes in the detection of electrical activity in the brain. We show that these sensors, requiring no electrical or physical contact with the body, can be used to monitor the human electroencephalogram (EEG) revealing, as examples, the α and β rhythms and the α blocking phenomenon. We suggest that the advantages offered by these sensors compared with the currently used contact (Ag/AgCl) electrodes may act to stimulate new developments in multichannel EEG monitoring and in real-time electrical imaging of the brain.

  4. Respiratory-driven Na+ electrical potential in the bacterium Vitreoscilla.

    PubMed

    Efiok, B J; Webster, D A

    1990-05-15

    Vitreoscilla is a Gram-negative bacterium with unique respiratory physiology in which Na+ was implicated as a coupling cation for the generation of a transmembrane electrical gradient (delta psi). Thus, cells respiring in the presence of 110 mM Na+ generated a delta psi of -142 mV compared to only -42 and -56 mV for Li+ and choline, respectively, and even the -42 and -56 mV were insensitive to the protonophore 3,5-di-tert-butyl-4-hydroxybenzaldehyde (DTHB). The kinetics of delta psi formation and collapse correlated well with the kinetics of Na+ fluxes but not with those of H+ fluxes. Cyanide inhibited respiration, Na+ extrusion, and delta psi formation 81% or more, indicating that delta psi formation and Na+ extrusion were coupled to respiration. Experiments were performed to distinguish among three possible transport systems for this coupling: (1) a Na(+)-transporting ATPase; (2) an electrogenic Na+/H+ antiport system; (3) a primary Na+ pump directly driven by the free energy of electron transport. DCCD and arsenate decreased cellular ATP up to 86% but had no effect on delta psi, evidence against a Na(+)-transporting ATPase. Low concentrations of DTHB had no effect on delta psi; high concentrations transiently collapsed delta psi, but led to a stimulation of Na+ extrusion, the opposite of that expected for a Na+/H+ antiport system. Potassium ion, which collapses delta psi, also stimulated Na+ extrusion. The experimental evidence is against Na+ extrusion by mechanisms 1 and 2 and supports the existence of a respiratory-driven primary Na+ pump for generating delta psi in Vitreoscilla. PMID:2372555

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

    SciTech Connect

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

    2011-05-11

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

  6. Existing Whole-House Solutions Case Study: Evaluating Energy Savings in All-Electric Public Housing in the Pacific Northwest

    SciTech Connect

    2014-03-01

    This project analyzes the cost effectiveness of energy-saving measures installed by a large public housing authority in Salishan, and evaluates those solutions to improve efficiency of affordable housing for new and existing homes. Research focuses on the modeled and measured energy usage of the first six phases of construction, and compares the energy usage of those phases to phase 7.

  7. Inverse solutions for electric and potential field imaging

    NASA Astrophysics Data System (ADS)

    Johnson, Christopher R.; MacLeod, Robert S.

    1993-08-01

    One of the fundamental problems in theoretical electrocardiography can be characterized by an inverse problem. In this paper, we present new methods for achieving better estimates of heart surface potential distributions in terms of torso potentials through an inverse procedure. First, an adaptive meshing algorithm is described which minimizes the error in the forward problem due to spatial discretization. We have found that since the inverse problem relies directly on the accuracy of the forward solution, adaptive meshing produces a more accurate inverse transfer matrix. Secondly, we introduce a new local regularization procedure. This method works by breaking the global transfer matrix into sub-matrices and performing regularization only on those sub-matrices which have large condition numbers. Furthermore, the regularization parameters are specifically 'tuned' for each sub-matrix using an a priori scheme based on the L-curve method. This local regularization method provides substantial increases in accuracy when compared to global regularization schemes. Finally, we present specific examples of the implementation of these schemes using models derived from magnetic resonance imaging data from a human subject.

  8. Apparent cooperativity of amino acid transport in Halobacterium halobium - Effect of electrical potential

    NASA Technical Reports Server (NTRS)

    Lanyi, J. K.

    1978-01-01

    Active serine accumulation in cell envelope vesicles from Halobacterium halobium proceeds by co-transport with Na(+) and can be induced by either transmembrane electrical potential or transmembrane Na(+) concentration difference. It was shown earlier that in the former case the initial transport rate is a fourth-power function of the magnitude of the electrochemical potential difference of sodium ions, and in the latter, a second-power function. A possible interpretation of this finding is cooperativity of sodium-transporting sites in the transport carrier. When both kinds of driving force are imposed simultaneously on the vesicles, fourth-power dependence on the total potential difference of sodium ions is obtained, suggesting that the transport carrier is regulated by the electrical potential. Heat treatment of the vesicles at 48 C partially inactivates transport and abolishes this effect of the electrical potential.

  9. Fractal growth kinetics and electric potential oscillations during electropolymerization of pyrrole.

    PubMed

    Das, Ishwar; Agrawal, Namita R; Gupta, Sanjeev Kumar; Gupta, Sujeet Kumar; Rastogi, R P

    2009-05-01

    Fractal growth, growth kinetics, and electrical conductivity of aggregates obtained during electropolymerization in the systems (A) pyrrole-4-toluene sulfonic acid silver salt (4-TSS)-acetonitrile, (B) pyrrole-4-TSS-ZnSO(4)-acetonitrile, and (C) pyrrole-4-TSS-aniline-acetonitrile were investigated. In the case of system (A), effect of [4-TSS], [pyrrole], field intensity, and solvents H(2)O and CH(3)OH on morphology, fractal character, and growth kinetics was also studied. Fractal growth data were examined in detail. During studies on system (A), electric potential oscillations were observed and subjected to detailed study. The results indicate that fractal growth pattern and electric potential oscillations are inter-related. The mechanism of development of fractal growth, dendritic structure, and electric potential oscillations is discussed in terms of diffusion-limited aggregation and modified Diaz's mechanism, which explains the random movement of radical cations.

  10. Electrical potentials from the eye and optic nerve of Strombus: effects of electrical stimulation of the optic nerve.

    PubMed

    Gillary, H L

    1977-02-01

    1. Photic stimulation of the mature eye of Strombus can evoke in the optic nerve 'on' activity in numerous small afferent fibres and repetitive 'off' bursts of afferent impulses in a smaller number of larger fibres. 2. Synchronous invasion of the eye by electrically evoked impulses in small optic nerve fibres (apparently the 'on' afferents, antidromically activated) can evoke a burst of impulses in the larger 'off' fibres which propagate away from the eye. Invasion of the eye via one branch of optic nerve can evoke an answering burst in another branch. 3. Such electrically evoked bursts are similar to light-evoked 'off' bursts with respect to their impulse composition, their ability to be inhibited by illumination of the eye, and their susceptibility to MgCl2 anaesthesia. 4. Invasion of the eye by a train of repetitive electrically evoked impulses in the absence of photic stimulation can give rise to repetitive 'off' bursts as well as concomitant oscillatory potentials in the eye which are similar to those normally evoked by cessation of a photic stimulus. 5. The electrically evoked 'off' bursts appear to be caused by an excitatory rebound following the cessation of inhibitory synaptic input from photoreceptors which can be antidromically activated by electrical stimulation of the optic nerve. 6. The experimental results suggest that the rhythmic discharge of the 'off' fibres evoked by the cessation of a photic stimulus is mediated by the abrupt decrease of inhibitory synaptic input from the receptors. PMID:192827

  11. Spacecraft electrical potential estimation in worst case environment

    NASA Astrophysics Data System (ADS)

    Toyoda, Kazuhiro

    2016-07-01

    There are no established simulation criteria for the space environment that produces the worst-case spacecraft charging. An ISO New Work Item Proposal entitled Potential Estimation in Worst-Case Environments was approved for ISO TC20/SC14/WG4. One of the aims of this project is to establish a worst-case charging environment for spacecraft charging simulation. In this paper, we compare round-robin simulations using the MUSCAT and Nascap-2k spacecraft charging codes and published measured worst-case GEO charging environments. As originally envisioned, the SPIS code was also to be part of the round-robin. However, SPIS code results are not available at this time. Thus, in this paper, MUSCAT results are compared with Nascap-2k results. In the round-robin simulation, the same spacecraft model is used with the same material properties and simulations are done with the same environments. Finally our round-robin simulation results suggest the worst-case charging GEO spacecraft charging environment that may be used for spacecraft modeling, design, and testing.

  12. Evaluation of Modeled and Measured Energy Savings in Existing All Electric Public Housing in the Pacific Northwest

    SciTech Connect

    Gordon, Andrew; Lubliner, Michael; Howard, Luke; Kunkle, Rick; Salzberg, Emily

    2014-04-01

    This project analyzes the cost effectiveness of energy savings measures installed by a large public housing authority in Salishan, a community in Tacoma Washington. Research focuses on the modeled and measured energy usage of the first six phases of construction, and compares the energy usage of those phases to phase 7. Market-ready energy solutions were also evaluated to improve the efficiency of affordable housing for new and existing (built since 2001) affordable housing in the marine climate of Washington State.

  13. Evaluating Energy Savings in All-Electric Public Housing in the Pacific Northwest, Tacoma, Washington (Fact Sheet)

    SciTech Connect

    Not Available

    2014-03-01

    This project analyzes the cost effectiveness of energy savings measures installed by a large public housing authority in Salishan, a community in Tacoma Washington. Research focuses on the modeled and measured energy usage of the first six phases of construction, and compares the energy usage of those phases to phase 7. Market-ready energy solutions were also evaluated to improve the efficiency of affordable housing for new and existing (built since 2001) affordable housing in the marine climate of Washington State.

  14. Adsorption of lysozyme on base metal surfaces in the presence of an external electric potential.

    PubMed

    Ei Ei, Htwe; Nakama, Yuhi; Tanaka, Hiroshi; Imanaka, Hiroyuki; Ishida, Naoyuki; Imamura, Koreyoshi

    2016-11-01

    The impact of external electric potential on the adsorption of a protein to base metal surfaces was examined. Hen egg white lysozyme (LSZ) and six types of base metal plates (stainless steel SUS316L (St), Ti, Ta, Zr, Cr, or Ni) were used as the protein and adsorption surface, respectively. LSZ was allowed to adsorb on the surface under different conditions (surface potential, pH, electrolyte type and concentration, surface material), which was monitored using an ellipsometer. LSZ adsorption was minimized in the potential range above a certain threshold and, in the surface potential range below the threshold, decreasing the surface potential increased the amount of protein adsorbed. The threshold potential for LSZ adsorption was shifted toward a positive value with increasing pH and was lower for Ta and Zr than for the others. A divalent anion salt (K2SO4) as an electrolyte exhibited the adsorption of LSZ in the positive potential range while a monovalent salt (KCl) did not. A comprehensive consideration of the obtained results suggests that two modes of interactions, namely the electric force by an external electric field and electrostatic interactions with ionized surface hydroxyl groups, act on the LSZ molecules and determine the extent of suppression of LSZ adsorption. All these findings appear to support the view that a base metal surface can be controlled for the affinity to a protein by manipulating the surface electric potential as has been reported on some electrode materials. PMID:27478958

  15. Adsorption of lysozyme on base metal surfaces in the presence of an external electric potential.

    PubMed

    Ei Ei, Htwe; Nakama, Yuhi; Tanaka, Hiroshi; Imanaka, Hiroyuki; Ishida, Naoyuki; Imamura, Koreyoshi

    2016-11-01

    The impact of external electric potential on the adsorption of a protein to base metal surfaces was examined. Hen egg white lysozyme (LSZ) and six types of base metal plates (stainless steel SUS316L (St), Ti, Ta, Zr, Cr, or Ni) were used as the protein and adsorption surface, respectively. LSZ was allowed to adsorb on the surface under different conditions (surface potential, pH, electrolyte type and concentration, surface material), which was monitored using an ellipsometer. LSZ adsorption was minimized in the potential range above a certain threshold and, in the surface potential range below the threshold, decreasing the surface potential increased the amount of protein adsorbed. The threshold potential for LSZ adsorption was shifted toward a positive value with increasing pH and was lower for Ta and Zr than for the others. A divalent anion salt (K2SO4) as an electrolyte exhibited the adsorption of LSZ in the positive potential range while a monovalent salt (KCl) did not. A comprehensive consideration of the obtained results suggests that two modes of interactions, namely the electric force by an external electric field and electrostatic interactions with ionized surface hydroxyl groups, act on the LSZ molecules and determine the extent of suppression of LSZ adsorption. All these findings appear to support the view that a base metal surface can be controlled for the affinity to a protein by manipulating the surface electric potential as has been reported on some electrode materials.

  16. The electric potential distribution profile in a naturally charged fluidized bed and its effects

    SciTech Connect

    Fujino, M.; Ogata, S.; Shinohara, H.

    1985-01-01

    The electric potential profile on fluidized particles in acrylic and iron columns was measured with a spherical probe. The order of magnitude of the measurements is reasonable. The potential is strongly affected by the column material, the particle size, the type of particles, the gas velocity and humidity, and probably the diameter of the column. The dependence of the specific charge of the particles on the operating parameters is not clear. The calculated potential distributions show a maximum radial electric intensity near the column wall, with the resulting coalescence of particles leading to dead space and channeling.

  17. Effects of microstructure and water on the electrical potentials in bone induced by ultrasound irradiation

    SciTech Connect

    Tsuneda, H.; Matsukawa, S.; Takayanagi, S.; Matsukawa, M.; Mizuno, K.; Yanagitani, T.

    2015-02-16

    The healing mechanism of bone fractures by low intensity pulse ultrasound is yet to be fully understood. There have been many discussions regarding how the high frequency dynamic stress can stimulate numerous cell types through various pathways. As one possible initial process of this mechanism, we focus on the piezoelectricity of bone and demonstrate that bone can generate electrical potentials by ultrasound irradiation in the MHz range. We have fabricated ultrasonic bone transducers using bovine cortical bone as the piezoelectric device. The ultrasonically induced electrical potentials in the transducers change as a function of time during immersed ultrasonic pulse measurements and become stable when the bone is fully wet. In addition, the magnitude of the induced electrical potentials changes owing to the microstructure in the cortical bone. The potentials of transducers with haversian structure bone are higher than those of plexiform structure bone, which informs about the effects of bone microstructure on the piezoelectricity.

  18. Modelling the potential for wind energy integration on China’s coal-heavy electricity grid

    NASA Astrophysics Data System (ADS)

    Davidson, Michael R.; Zhang, Da; Xiong, Weiming; Zhang, Xiliang; Karplus, Valerie J.

    2016-07-01

    Expanding the use of wind energy for electricity generation forms an integral part of China’s efforts to address degraded air quality and climate change. However, the integration of wind energy into China’s coal-heavy electricity system presents significant challenges owing to wind’s variability and the grid’s system-wide inflexibilities. Here we develop a model to predict how much wind energy can be generated and integrated into China’s electricity mix, and estimate a potential production of 2.6 petawatt-hours (PWh) per year in 2030. Although this represents 26% of total projected electricity demand, it is only 10% of the total estimated physical potential of wind resources in the country. Increasing the operational flexibility of China’s coal fleet would allow wind to deliver nearly three-quarters of China’s target of producing 20% of primary energy from non-fossil sources by 2030.

  19. Single potential analysis of cavernous electrical activity (SPACE). Experiences, limitations and perspectives.

    PubMed

    Djamilian, M H; Truss, M C; Tan, H K; Anton, P; Stief, C G; Jonas, U

    1993-01-01

    Cavernous electromyography was first introduced by Wagner and Gerstenberg in 1989. The authors developed a refined method of cavernous electromyography by means of single potential analysis in introduced this method into clinical Urology as a diagnostic procedure for the evaluation of patients presenting with erectile dysfunction. To date, our experience with single potential analysis of cavernous electrical activity (SPACE) includes more than 500 patients with erectile dysfunction of various etiologies and 92 normal control subjects. Several technical modifications and refinements have been adopted during the last 4 years. In normal control subjects, SPACE shows a regular pattern of activity with long phases of electrical silence at the usual amplification interrupted by synchronous low frequency, high amplitude potentials. In patients with disruption of the peripheral autonomic supply, typical asynchronous potentials with higher frequencies and irregular shape are observed. In complete spinal cord lesions, abnormal as well as normal electrical activity is found. In patients with a long history of insulin-dependent diabetes and presumably cavernous smooth muscle degeneration, SPACE recordings show irregular potentials with low amplitudes and slow depolarization speed. Synchronization of electrical activity is usually absent. Recent studies on patients with venous leakage show that SPACE provides independent clinical information about the cavernous smooth musculature. The recording of cavernous electrical activity is possible and reproductible. In the future, a new software for one-line date processing, storage and interpretation of SPACE signals will be available.

  20. Tension moderation and fluctuation spectrum in simulated lipid membranes under an applied electric potential.

    PubMed

    Loubet, Bastien; Lomholt, Michael Andersen; Khandelia, Himanshu

    2013-10-28

    We investigate the effect of an applied electric potential on the mechanics of a coarse grained POPC bilayer under tension. The size and duration of our simulations allow for a detailed and accurate study of the fluctuations. Effects on the fluctuation spectrum, tension, bending rigidity, and bilayer thickness are investigated in detail. In particular, the least square fitting technique is used to calculate the fluctuation spectra. The simulations confirm a recently proposed theory that the effect of an applied electric potential on the membrane will be moderated by the elastic properties of the membrane. In agreement with the theory, we find that the larger the initial tension the larger the effect of the electric potential. Application of the electric potential increases the amplitude of the long wavelength part of the spectrum and the bending rigidity is deduced from the short wavelength fluctuations. The effect of the applied electric potential on the bending rigidity is non-existent within error bars. However, when the membrane is stretched there is a point where the bending rigidity is lowered due to a decrease of the thickness of the membrane. All these effects should prove important for mechanosensitive channels and biomembrane mechanics in general.

  1. Non-invasive electrocardiogram detection of in vivo zebrafish embryos using electric potential sensors

    NASA Astrophysics Data System (ADS)

    Rendon-Morales, E.; Prance, R. J.; Prance, H.; Aviles-Espinosa, R.

    2015-11-01

    In this letter, we report the continuous detection of the cardiac electrical activity in embryonic zebrafish using a non-invasive approach. We present a portable and cost-effective platform based on the electric potential sensing technology, to monitor in vivo electrocardiogram activity from the zebrafish heart. This proof of principle demonstration shows how electrocardiogram measurements from the embryonic zebrafish may become accessible by using electric field detection. We present preliminary results using the prototype, which enables the acquisition of electrophysiological signals from in vivo 3 and 5 days-post-fertilization zebrafish embryos. The recorded waveforms show electrocardiogram traces including detailed features such as QRS complex, P and T waves.

  2. Multimodality evoked potentials and electrically elicited blink reflex in optic neuritis.

    PubMed

    Tackmann, W; Ettlin, T; Strenge, H

    1982-01-01

    Pattern shift visual evoked potentials, brain stem auditory evoked potentials, spinal and scalp recorded somatosensory evoked potentials, and electrically elicited blink reflexes were investigated in 32 patients with isolated optic neuritis. Eleven patients were shown to have one additional lesion in the central nervous system outside the optic nerve. Therefore, cases with optic neuritis of unknown origin should be considered as possible cases of multiple sclerosis. PMID:6181223

  3. Kinetic Model of Electric Potentials in Localized Collisionless Plasma Structures under Steady Quasi-gyrotropic Conditions

    NASA Technical Reports Server (NTRS)

    Schindler, K.; Birn, J.; Hesse, M.

    2012-01-01

    Localized plasma structures, such as thin current sheets, generally are associated with localized magnetic and electric fields. In space plasmas localized electric fields not only play an important role for particle dynamics and acceleration but may also have significant consequences on larger scales, e.g., through magnetic reconnection. Also, it has been suggested that localized electric fields generated in the magnetosphere are directly connected with quasi-steady auroral arcs. In this context, we present a two-dimensional model based on Vlasov theory that provides the electric potential for a large class of given magnetic field profiles. The model uses an expansion for small deviation from gyrotropy and besides quasineutrality it assumes that electrons and ions have the same number of particles with their generalized gyrocenter on any given magnetic field line. Specializing to one dimension, a detailed discussion concentrates on the electric potential shapes (such as "U" or "S" shapes) associated with magnetic dips, bumps, and steps. Then, it is investigated how the model responds to quasi-steady evolution of the plasma. Finally, the model proves useful in the interpretation of the electric potentials taken from two existing particle simulations.

  4. Assessment of Energy Savings Potential from the Use of Demand Controlled Ventilation in General Office Spaces in California

    SciTech Connect

    Hong, Tianzhen; Fisk, William

    2010-01-01

    A prototypical office building meeting the prescriptive requirements of the 2008 California building energy efficiency standards (Title 24) was used in EnergyPlus simulations to calculate the energy savings potential of demand controlled ventilation (DCV) in five typical California climates per three design occupancy densities and two minimum ventilation rates. The assumed minimum ventilation rates in offices without DCV, based on two different measurement methods employed in a large survey, were 38 and 13 L/s per occupant. The results of the life cycle cost analysis show DCV is cost effective for office spaces if the typical minimum ventilation rate without DCV is 38 L/s per person, except at the low design occupancy of 10.8 people per 100 m2 in climate zones 3 (north coast) and 6 (south Coast). DCV was not found to be cost effective if the typical minimum ventilation rate without DCV is 13 L/s per occupant, except at high design occupancy of 21.5 people per 100 m2 in climate zones 14 (desert) and 16 (mountains). Until the large uncertainties about the base case ventilation rates in offices without DCV are reduced, the case for requiring DCV in general office spaces will be a weak case. Under the Title 24 Standards office occupant density of 10.8 people per 100 m2, DCV becomes cost effective when the base case minimum ventilation rate is greater than 42.5, 43.0, 24.0, 19.0, and 18.0 L/s per person for climate zone 3, 6, 12, 14, and 16 respectively.

  5. The potential and electric field in the cochlear outer hair cell membrane

    PubMed Central

    Harland, Ben; Lee, Wen-han; Brownell, William E.; Sun, Sean X.; Spector, Alexander A.

    2015-01-01

    Outer hair cell electromechanics, critically important to mammalian active hearing, is driven by the cell membrane potential. The membrane protein prestin is a crucial component of the active outer hair cell’s motor. The focus of the paper is the analysis of the local membrane potential and electric field resulting from the interaction of electric charges involved. Here the relevant charges are the ions inside and outside the cell, lipid bilayer charges, and prestin-associated charges (mobile-transferred by the protein under the action of the applied field and stationary-relatively unmoved by the field). The electric potentials across and along the membrane are computed for the case of an applied DC-field. The local amplitudes and phases of the potential under different frequencies are analyzed for the case of a DC+AC-field. We found that the effect of the system of charges alters the electric potential and internal field, which deviate significantly from their traditional linear and constant distributions. Under DC+AC conditions, the strong frequency dependence of the prestin mobile charge has a relatively small effect on the amplitude and phase of the resulting potential. The obtained results can help in a better understanding and experimental verification of the mechanism of prestin performance. PMID:25687712

  6. The potential and electric field in the cochlear outer hair cell membrane.

    PubMed

    Harland, Ben; Lee, Wen-han; Brownell, William E; Sun, Sean X; Spector, Alexander A

    2015-05-01

    Outer hair cell electromechanics, critically important to mammalian active hearing, is driven by the cell membrane potential. The membrane protein prestin is a crucial component of the active outer hair cell's motor. The focus of the paper is the analysis of the local membrane potential and electric field resulting from the interaction of electric charges involved. Here the relevant charges are the ions inside and outside the cell, lipid bilayer charges, and prestin-associated charges (mobile-transferred by the protein under the action of the applied field, and stationary-relatively unmoved by the field). The electric potentials across and along the membrane are computed for the case of an applied DC-field. The local amplitudes and phases of the potential under different frequencies are analyzed for the case of a DC + AC-field. We found that the effect of the system of charges alters the electric potential and internal field, which deviate significantly from their traditional linear and constant distributions. Under DC + AC conditions, the strong frequency dependence of the prestin mobile charge has a relatively small effect on the amplitude and phase of the resulting potential. The obtained results can help in a better understanding and experimental verification of the mechanism of prestin performance. PMID:25687712

  7. 3D mapping of nanoscale electric potentials in semiconductor structures using electron-holographic tomography

    NASA Astrophysics Data System (ADS)

    Wolf, Daniel; Lubk, Axel; Prete, Paola; Lovergine, Nico; Lichte, Hannes

    2016-09-01

    Off-axis electron holography (EH) is a powerful method for mapping projected electric potentials, such as built-in potentials in semiconductor devices, in two dimensions (2D) at nanometer resolution. However, not well-defined thickness profiles, surface effects, and composition changes of the sample under investigation complicate the interpretation of the projected potentials. Here, we demonstrate how these problems can be overcome by combining EH with tomographic techniques, that is, electron holographic tomography (EHT), reconstructing electric potentials in 3D. We present EHT reconstructions of an n-type MOSFET including its dopant-related built-in potentials inside the device, as well as of a GaAs/AlGaAs core-multishell nanowire containing a 5 nm thick quantum well tube.

  8. [Effect of the initial anode potential on electricity generation in microbial fuel cell].

    PubMed

    Fan, Ming-Zhi; Liang, Peng; Cao, Xiao-Xin; Huang, Xia

    2008-01-01

    The initial anode potential of the microbial fuel cell (MFC) was changed by additional circuit in the anode chamber, and the influence of the initial anode potential on the electricigens was studied. When the initial anode potential was 350 mV (vs Hg/Hg2 Cl2), the growth of microorganisms was much slower than that of the microorganisms which grew on the anode with an initial potential of -200 mV or 200 mV (vs Hg/Hg2 Cl2). After stable electricity generation, the anode resistances of the three MFCs, which had initial anode potentials of 350 mV, 200 mV and -200 mV respectively, were 71 Omega, 43 Omega and 80 Omega. The community structures in MFCs, before and after the electricity generation, were also studied by denaturing gradient gel electrophoresis (DGGE). Clostridium sticklandii, Pseudomonas mendocina and Paenibacillus taejonensis were the three most enriched strains on the anode.

  9. Relationships between Electrically Evoked Potentials and Loudness Growth in Bilateral Cochlear Implant Users

    PubMed Central

    Kirby, Benjamin; Brown, Carolyn; Abbas, Paul; Etler, Christine; O’Brien, Sara

    2011-01-01

    SHORT SUMMARY Bilateral cochlear implantation has motivated efforts to ensure that sounds presented at equal levels to each ear are perceived as equally loud. Psychophysical loudness balancing is not always practical, especially with pediatric users. Electrophysiological potentials -- electrically evoked auditory brain stem response (EABR) and electrically evoked compound action potential (ECAP) measures -- may provide a means of approximating loudness balance. It was hypothesized that stimuli evoking equal amplitude neural responses would be more closely matched in loudness than stimuli with equal current levels. No significant differences in loudness discrepancy across ears were found for ECAP, EABR or matched current levels. PMID:22246138

  10. Direct current electrical potential measurement of the growth of small cracks

    NASA Technical Reports Server (NTRS)

    Gangloff, Richard P.; Slavik, Donald C.; Piascik, Robert S.; Van Stone, Robert H.

    1992-01-01

    The analytical and experimental aspects of the direct-current electrical potential difference (dcEPD) method for continuous monitoring of the growth kinetics of short (50 to 500 microns) fatigue cracks are reviewed, and successful applications of the deEPD method to study fatigue crack propagation in a variety of metallic alloys exposed to various environments are described. Particular attention is given to the principle of the dcEPD method, the analytical electrical potential calibration relationships, and the experimental procedures and equipment.

  11. Save Energy: Save Money!

    ERIC Educational Resources Information Center

    Eccli, Eugene; And Others

    This publication is a collection of inexpensive energy saving tips and home improvements for home owners, particularly in low-income areas or in older homes. Section titles are: (1) Keeping Warm; (2) Getting Heat Where You Need It; (3) Using the Sun; (4) Furnaces, Stoves, and Fireplaces; (5) Insulation and Other Energy Needs; (6) Do-It-Yourself…

  12. How to Save Money by Saving Energy.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC.

    This pamphlet presents energy conservation tips to help consumers save money. Conservation measures suggested here cover topics such as: (1) insulation; (2) space heating and cooling; (3) hot water heating; (4) cooking; (5) laundry; (6) lighting; (7) electrical appliances; (8) buying or building a home; and (9) buying, maintaining and driving a…

  13. Single cell wound generates electric current circuit and cell membrane potential variations that requires calcium influx.

    PubMed

    Luxardi, Guillaume; Reid, Brian; Maillard, Pauline; Zhao, Min

    2014-07-24

    Breaching of the cell membrane is one of the earliest and most common causes of cell injury, tissue damage, and disease. If the compromise in cell membrane is not repaired quickly, irreversible cell damage, cell death and defective organ functions will result. It is therefore fundamentally important to efficiently repair damage to the cell membrane. While the molecular aspects of single cell wound healing are starting to be deciphered, its bio-physical counterpart has been poorly investigated. Using Xenopus laevis oocytes as a model for single cell wound healing, we describe the temporal and spatial dynamics of the wound electric current circuitry and the temporal dynamics of cell membrane potential variation. In addition, we show the role of calcium influx in controlling electric current circuitry and cell membrane potential variations. (i) Upon wounding a single cell: an inward electric current appears at the wound center while an outward electric current is observed at its sides, illustrating the wound electric current circuitry; the cell membrane is depolarized; calcium flows into the cell. (ii) During cell membrane re-sealing: the wound center current density is maintained for a few minutes before decreasing; the cell membrane gradually re-polarizes; calcium flow into the cell drops. (iii) In conclusion, calcium influx is required for the formation and maintenance of the wound electric current circuitry, for cell membrane re-polarization and for wound healing.

  14. Electric field modulation of the membrane potential in solid-state ion channels.

    PubMed

    Guan, Weihua; Reed, Mark A

    2012-12-12

    Biological ion channels are molecular devices that allow a rapid flow of ions across the cell membrane. Normal physiological functions, such as generating action potentials for cell-to-cell communication, are highly dependent on ion channels that can open and close in response to external stimuli for regulating ion permeation. Mimicking these biological functions using synthetic structures is a rapidly progressing yet challenging area. Here we report the electric field modulation of the membrane potential phenomena in mechanically and chemically robust solid-state ion channels, an abiotic analogue to the voltage-gated ion channels in living systems. To understand the complex physicochemical processes in the electric field regulated membrane potential behavior, both quasi-static and transient characteristics of converting transmembrane ion gradients into electric potential are investigated. It is found that the transmembrane potential can be adequately tuned by an external electrical stimulation, thanks to the unique properties of the voltage-regulated selective ion transport through a nanoscale channel.

  15. An economic analysis of the electricity generation potential from biogas resources in the state of Indiana

    NASA Astrophysics Data System (ADS)

    Giraldo, Juan S.

    Anaerobic digestion is a process that is a common part of organic waste management systems and is used in concentrated animal feeding operations (CAFOs), wastewater treatment plants (WWTPs), and municipal solid waste (MSW) landfills. The process produces biogas, which contains methane, and it can be burned to generate electricity. Previous reports have indicated that based on the availability of feedstocks there is a large potential for biogas production and use for electricity generation in the state of Indiana. However, these reports varied in their consideration of important factors that affect the technical and economic feasibility of being able to develop the resources available. The goal of this thesis is to make a more targeted assessment of the electricity generation potential from biogas resources at CAFOs, WWTPs, and MSW landfills in Indiana. A capital budgeting model is used to estimate the net present value (NPV) of biogas electricity projects at facilities that are identified as technically suitable. A statewide estimate of the potential generation capacity is made by estimating the number of facilities that could profitably undertake a biogas electricity project. In addition this thesis explored the impact that different incentive policies would have on the economic viability of these projects. The results indicated that the electricity generation potential is much smaller when technical and economic factors are taken into account in addition to feedstock availability. In particular it was found that projects at hog farms are unlikely to be economically feasible in the present even when financial incentives are considered. In total, 47.94 MW of potential generating capacity is estimated from biogas production at CAFOs, WWTPs, and MSW landfills. Though results indicated that 37.10 MW of capacity are economically feasible under current operating conditions, sensitivity analysis reveals that these projects are very sensitive to capital cost assumptions

  16. Problems and the potential direction of reforms for the current individual medical savings accounts in the Chinese health care system.

    PubMed

    Kong, Xiangjin; Yang, Yang; Gong, Fuqing; Zhao, Mingjie

    2012-12-01

    Individual health savings accounts are an important part of the current basic medical insurance system for urban workers in China. Since 1998 when the system of personal medical insurance accounts was first implemented, there has been considerable controversy over its function and significance within different social communities. This paper analyzes the main problems in the practical implementation of individual medical insurance accounts and discusses the social and cultural foundations for the establishment of family health savings accounts from the perspective of Chinese Confucian familism. Accordingly, it addresses the direction of the reform and the development of the current system of individual health insurance accounts in China.

  17. Kennecott Utah Copper Corporation: Facility Utilizes Energy Assessments to Identify $930,000 in Potential Annual Savings

    SciTech Connect

    Not Available

    2004-07-01

    Kennecott Utah Copper Corporation (KUCC) used targeted energy assessments in the smelter and refinery at its Bingham Canyon Mine, near Salt Lake City, Utah. The assessment focused mainly on the energy-intensive processes of copper smelting and refining. By implementing the projects identified, KUCC could realize annual cost savings of $930,000 and annual energy savings of 452,000 MMBtu. The projects would also reduce maintenance, repair costs, waste, and environmental emissions. One project would use methane gas from an adjacent municipal dump to replace natural gas currently used to heat the refinery electrolyte.

  18. Microscopic Measurements of Electrical Potential in Hydrogenated Nanocrystalline Silicon Solar Cells: Preprint

    SciTech Connect

    Jiang, C. S.; Moutinho, H. R.; Reedy, R. C.; Al-Jassim, M. M.; Yan, B.; Yue, G.; Sivec, L.; Yang, J.; Guha, S.; Tong, X.

    2012-04-01

    We report on a direct measurement of electrical potential and field profiles across the n-i-p junction of hydrogenated nanocrystalline silicon (nc-Si:H) solar cells, using the nanometer-resolution potential imaging technique of scanning Kelvin probe force microscopy (SKPFM). It was observed that the electric field is nonuniform across the i layer. It is much higher in the p/i region than in the middle and the n/i region, illustrating that the i layer is actually slightly n-type. A measurement on a nc-Si:H cell with a higher oxygen impurity concentration shows that the nonuniformity of the electric field is much more pronounced than in samples having a lower O impurity, indicating that O is an electron donor in nc-Si:H materials. This nonuniform distribution of electric field implies a mixture of diffusion and drift of carrier transport in the nc-Si:H solar cells. The composition and structure of these nc-Si:H cells were further investigated by using secondary-ion mass spectrometry and Raman spectroscopy, respectively. The effects of impurity and structural properties on the electrical potential distribution and solar cell performance are discussed.

  19. Self-Potential (SP) and Active Electrical Geophysical Assessment of Bioremediation at a Contaminated Gasworks Plant

    NASA Astrophysics Data System (ADS)

    Kulessa, B.; Kalin, R.; Doherty, R.; Phillips, D.

    2006-05-01

    We have surveyed a former gasworks site in Portadown, Northern Ireland, using self-potential (SP), electrical resistivity, induced polarisation (IP), and ground conductivity (EM-31, EM-34, EM-61). Site lithology and hydrogeology were mapped in numerous trial pits, and groundwater redox conditions together with a host of associated biogeochemical and microbiological parameters have been monitored in several boreholes. A permeable reactive barrier (PRB) together with groundwater flow control (slurry wall) and monitored natural attenuation (MNA) are used for remediation of the complex site contamination, including hydrocarbon and heavy metals. The electrical geophysical surveys mapped the foundations of former infrastructure at the site and detected a formerly unknown tar well and a pit filled with mixed waste. In the contaminated regions of the site the total, measured SP signal is comprised of streaming potential and electrochemical components; in the uncontaminated regions the streaming potential is dominant and electrochemical potentials are negligible. The streaming potential coupling coefficient is estimated by relating the hydraulic potentials from borehole monitoring and groundwater flow modelling to the total SP signal measured in the uncontaminated regions. Residual SP is determined by subtracting the calculated streaming potential component from the total SP data, and the impact of spatially variable, bulk ground conductivity on streaming potential is elucidated. We investigate the relationship between residual SP and redox potential measured in several successive, contaminated aquifer layers separated by aquitards. The SP and electrical geophysical signatures of microbial processes naturally degrading the subsurface contaminants are examined. Preliminary findings from SP and electrical geophysical monitoring of artificially disturbed microbial processes and subsurface redox conditions are also presented.

  20. Electric potential changes prior to shear fracture in dry and saturated rocks

    NASA Astrophysics Data System (ADS)

    Yoshida, Shingo; Clint, Oswald C.; Sammonds, Peter R.

    Electric potential changes before shear rupture were measured using Darley Dale sandstone (quartz-rich) and Icelandic basalt (quartz-free) on both dry specimens and in the presence of pore fluid. We find that electric potential changed markedly just prior to dynamic rupture in dry and saturated sandstones and saturated basalt but we did not detect precursory signals in dry basalt. The absence of signals in dry basalt provides strong evidence that the piezoelectric effect and electrokinetic effect are dominant sources for precursory signals. Moreover we find that the amplitude of the precursory signals due to electrokinetic effect in saturated sandstone were as large as the coseismic signals. We propose that this signal is caused by accelerating evolution of dilatancy as cracks grow in the rock before rupture, resulting in water flow into the dilatant region with an electric current produced concurrently.

  1. Effect of water on the local electric potential of simulated ionic micelles

    SciTech Connect

    Brodskaya, Elena N.; Vanin, Alexander A.

    2015-07-28

    Ionic micelles in an aqueous solution containing single-charged counter-ions have been simulated by molecular dynamics. For both cationic and anionic micelles, it has been demonstrated that explicit description of solvent has strong effect on the micelle’s electric field. The sign of the local charge alters in the immediate vicinity of the micellar crown and the electric potential varies nonmonotonically. Two micelle models have been examined: the hybrid model with a rigid hydrocarbon core and the atomistic model. For three molecular models of water (Simple Point Charge model (SPC), Transferable Intermolecular Potential 5- Points (TIP5P) and two-centered S2), the results have been compared with those for the continuum solvent model. The orientational ordering of solvent molecules has strong effect on the local electric field surprisingly far from the micelle surface.

  2. Effect of water on the local electric potential of simulated ionic micelles

    NASA Astrophysics Data System (ADS)

    Brodskaya, Elena N.; Vanin, Alexander A.

    2015-07-01

    Ionic micelles in an aqueous solution containing single-charged counter-ions have been simulated by molecular dynamics. For both cationic and anionic micelles, it has been demonstrated that explicit description of solvent has strong effect on the micelle's electric field. The sign of the local charge alters in the immediate vicinity of the micellar crown and the electric potential varies nonmonotonically. Two micelle models have been examined: the hybrid model with a rigid hydrocarbon core and the atomistic model. For three molecular models of water (Simple Point Charge model (SPC), Transferable Intermolecular Potential 5- Points (TIP5P) and two-centered S2), the results have been compared with those for the continuum solvent model. The orientational ordering of solvent molecules has strong effect on the local electric field surprisingly far from the micelle surface.

  3. Assessment of potential and existing problems concerning interface between electric utilities and cogenerators

    SciTech Connect

    Not Available

    1980-03-01

    The potential and existing problems concerning the interface between US electric utilities and cogenerators are considered by region. Also considered are regulatory barriers, rates and contracts, economic feasibility, and impact on system planning. Finally, the impact of the National Energy Act on the marketability potential of cogeneration is reviewed. The three appendixes summarize the utility meetings on cogeneration held in Washington, DC, Los Angeles, and Chicago.

  4. General Electric composite ring-disk flywheel: Recent and potential developments

    NASA Technical Reports Server (NTRS)

    Coppa, A. P.

    1984-01-01

    Recent developments of the General Electric hybrid rotor design are described. The relation of the hybrid rotor design to flywheel designs that are especially suitable for spacecraft applications is discussed. Potential performance gains that can be achieved in such rotor designs by applying latest developments in materials, processing, and design methodology are projected. Indications are that substantial improvements can be obtained.

  5. The Dynamic Electric Polarizability of a Particle Bound by a Double Delta Potential

    ERIC Educational Resources Information Center

    Maize, M. A.; Smetanka, J. J.

    2008-01-01

    In this paper we derive an expression for the dynamic electric polarizability of a particle bound by a double delta potential for frequencies below and above the absolute value of the particle's ground state energy. The derived expression will be used to study some of the fundamental features of the system and its representation of real systems.…

  6. 40 CFR Appendix D to Part 72 - Calculation of Potential Electric Output Capacity

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Calculation of Potential Electric Output Capacity D Appendix D to Part 72 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Pt. 72, App. D Appendix D to Part 72—Calculation...

  7. Ion Permeability of Artificial Membranes Evaluated by Diffusion Potential and Electrical Resistance Measurements

    ERIC Educational Resources Information Center

    Shlyonsky, Vadim

    2013-01-01

    In the present article, a novel model of artificial membranes that provides efficient assistance in teaching the origins of diffusion potentials is proposed. These membranes are made of polycarbonate filters fixed to 12-mm plastic rings and then saturated with a mixture of creosol and "n"-decane. The electrical resistance and potential…

  8. 40 CFR Appendix D to Part 72 - Calculation of Potential Electric Output Capacity

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Calculation of Potential Electric Output Capacity D Appendix D to Part 72 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Pt. 72, App. D Appendix D to Part 72—Calculation...

  9. Dielectrophoretic forces and potentials induced on pairs of cells in an electric field.

    PubMed

    Foster, K R; Sowers, A E

    1995-09-01

    A combined numerical/experimental study is reported of the membrane potentials and dielectrophoretically induced forces between cells, membrane pressures, and velocity of attraction of cells under the influence of an electric field. This study was designed to explore electrical and mechanical effects produced by a field on cells in close proximity or undergoing electrically induced fusion. Laplace's equation for pairs of membrane-covered spheres in close proximity was solved numerically by the boundary element method, and the electrically induced forces on the cells and between cells were obtained by evaluating the Maxwell stress tensor. The velocity of approach of erythrocyte ghosts or fused ghosts in a 60-Hz field of 6 V/mm was measured experimentally, and the data were interpreted by using Batchelor's theory for hydrodynamic interaction of hard spheres. The numerical results show clearly the origin of the dielectrophoretic pressures and forces in fused and unfused cells and the effects of a nearby cell on the induced membrane potentials. The experimental results agree well with predictions based on the simple electrical model of the cell. The analysis shows the strong effect of hydrodynamic interactions between the cells in determining their velocity of approach. PMID:8519978

  10. Dielectrophoretic forces and potentials induced on pairs of cells in an electric field.

    PubMed Central

    Foster, K R; Sowers, A E

    1995-01-01

    A combined numerical/experimental study is reported of the membrane potentials and dielectrophoretically induced forces between cells, membrane pressures, and velocity of attraction of cells under the influence of an electric field. This study was designed to explore electrical and mechanical effects produced by a field on cells in close proximity or undergoing electrically induced fusion. Laplace's equation for pairs of membrane-covered spheres in close proximity was solved numerically by the boundary element method, and the electrically induced forces on the cells and between cells were obtained by evaluating the Maxwell stress tensor. The velocity of approach of erythrocyte ghosts or fused ghosts in a 60-Hz field of 6 V/mm was measured experimentally, and the data were interpreted by using Batchelor's theory for hydrodynamic interaction of hard spheres. The numerical results show clearly the origin of the dielectrophoretic pressures and forces in fused and unfused cells and the effects of a nearby cell on the induced membrane potentials. The experimental results agree well with predictions based on the simple electrical model of the cell. The analysis shows the strong effect of hydrodynamic interactions between the cells in determining their velocity of approach. PMID:8519978

  11. Computational Modeling of Single Neuron Extracellular Electric Potentials and Network Local Field Potentials using LFPsim.

    PubMed

    Parasuram, Harilal; Nair, Bipin; D'Angelo, Egidio; Hines, Michael; Naldi, Giovanni; Diwakar, Shyam

    2016-01-01

    Local Field Potentials (LFPs) are population signals generated by complex spatiotemporal interaction of current sources and dipoles. Mathematical computations of LFPs allow the study of circuit functions and dysfunctions via simulations. This paper introduces LFPsim, a NEURON-based tool for computing population LFP activity and single neuron extracellular potentials. LFPsim was developed to be used on existing cable compartmental neuron and network models. Point source, line source, and RC based filter approximations can be used to compute extracellular activity. As a demonstration of efficient implementation, we showcase LFPs from mathematical models of electrotonically compact cerebellum granule neurons and morphologically complex neurons of the neocortical column. LFPsim reproduced neocortical LFP at 8, 32, and 56 Hz via current injection, in vitro post-synaptic N2a, N2b waves and in vivo T-C waves in cerebellum granular layer. LFPsim also includes a simulation of multi-electrode array of LFPs in network populations to aid computational inference between biophysical activity in neural networks and corresponding multi-unit activity resulting in extracellular and evoked LFP signals. PMID:27445781

  12. Computational Modeling of Single Neuron Extracellular Electric Potentials and Network Local Field Potentials using LFPsim

    PubMed Central

    Parasuram, Harilal; Nair, Bipin; D'Angelo, Egidio; Hines, Michael; Naldi, Giovanni; Diwakar, Shyam

    2016-01-01

    Local Field Potentials (LFPs) are population signals generated by complex spatiotemporal interaction of current sources and dipoles. Mathematical computations of LFPs allow the study of circuit functions and dysfunctions via simulations. This paper introduces LFPsim, a NEURON-based tool for computing population LFP activity and single neuron extracellular potentials. LFPsim was developed to be used on existing cable compartmental neuron and network models. Point source, line source, and RC based filter approximations can be used to compute extracellular activity. As a demonstration of efficient implementation, we showcase LFPs from mathematical models of electrotonically compact cerebellum granule neurons and morphologically complex neurons of the neocortical column. LFPsim reproduced neocortical LFP at 8, 32, and 56 Hz via current injection, in vitro post-synaptic N2a, N2b waves and in vivo T-C waves in cerebellum granular layer. LFPsim also includes a simulation of multi-electrode array of LFPs in network populations to aid computational inference between biophysical activity in neural networks and corresponding multi-unit activity resulting in extracellular and evoked LFP signals. PMID:27445781

  13. A Comprehensive View of Global Potential for Hydro-generated Electricity

    SciTech Connect

    Zhou, Yuyu; Hejazi, Mohamad I.; Smith, Steven J.; Edmonds, James A.; Li, Hongyi; Clarke, Leon E.; Calvin, Katherine V.; Thomson, Allison M.

    2015-09-01

    In this study, we assess global hydropower potential using runoff and stream flow data, along with turbine technology performance, cost assumptions, and environmental considerations. The results provide the first comprehensive quantification of global hydropower potential including gross, technical, economic, and exploitable estimates. Total global potential of gross, technical, economic, and exploitable hydropower are estimated to be approximately 128, 39, 32, and 27 petawatt hours per year, respectively. The economic and exploitable potential of hydropower are calculated at less than 9 cents/kWh. We find that hydropower has the potential to supply a significant portion of the world energy needs, although this potential varies substantially by region. Globally, hydropower can potentially supply about 1.5 times the total electricity demand in 2005. Estimated hydropower resources in a number of countries are sufficient to accommodate their demand for electricity in 2005, e.g., Brazil (5.6 times), Russia (4.6 times), and Canada (3.5 times). A sensitivity analysis indicates that hydropower estimates are not highly sensitive to five key parameters: design flow (varying by -2% to +1% at less than 9 cents/kWh), cost and financing options (by -7% to +6%), turbine efficiency (by -10% to +10%), stream flow (by -10% to +10%), and fixed charge rate (by -6% to 5%). This sensitivity analysis emphasizes the reliable role of hydropower for future energy systems, when compared to other renewable energy resources with larger uncertainty in their future potentials.

  14. Electric Current Filamentation at a Non-potential Magnetic Null-point Due to Pressure Perturbation

    NASA Astrophysics Data System (ADS)

    Jelínek, P.; Karlický, M.; Murawski, K.

    2015-10-01

    An increase of electric current densities due to filamentation is an important process in any flare. We show that the pressure perturbation, followed by an entropy wave, triggers such a filamentation in the non-potential magnetic null-point. In the two-dimensional (2D), non-potential magnetic null-point, we generate the entropy wave by a negative or positive pressure pulse that is launched initially. Then, we study its evolution under the influence of the gravity field. We solve the full set of 2D time dependent, ideal magnetohydrodynamic equations numerically, making use of the FLASH code. The negative pulse leads to an entropy wave with a plasma density greater than in the ambient atmosphere and thus this wave falls down in the solar atmosphere, attracted by the gravity force. In the case of the positive pressure pulse, the plasma becomes evacuated and the entropy wave propagates upward. However, in both cases, owing to the Rayleigh-Taylor instability, the electric current in a non-potential magnetic null-point is rapidly filamented and at some locations the electric current density is strongly enhanced in comparison to its initial value. Using numerical simulations, we find that entropy waves initiated either by positive or negative pulses result in an increase of electric current densities close to the magnetic null-point and thus the energy accumulated here can be released as nanoflares or even flares.

  15. Reconstruction of multiple gastric electrical wave fronts using potential-based inverse methods

    NASA Astrophysics Data System (ADS)

    Kim, J. H. K.; Pullan, A. J.; Cheng, L. K.

    2012-08-01

    One approach for non-invasively characterizing gastric electrical activity, commonly used in the field of electrocardiography, involves solving an inverse problem whereby electrical potentials on the stomach surface are directly reconstructed from dense potential measurements on the skin surface. To investigate this problem, an anatomically realistic torso model and an electrical stomach model were used to simulate potentials on stomach and skin surfaces arising from normal gastric electrical activity. The effectiveness of the Greensite-Tikhonov or the Tikhonov inverse methods were compared under the presence of 10% Gaussian noise with either 84 or 204 body surface electrodes. The stability and accuracy of the Greensite-Tikhonov method were further investigated by introducing varying levels of Gaussian signal noise or by increasing or decreasing the size of the stomach by 10%. Results showed that the reconstructed solutions were able to represent the presence of propagating multiple wave fronts and the Greensite-Tikhonov method with 204 electrodes performed best (correlation coefficients of activation time: 90%; pacemaker localization error: 3 cm). The Greensite-Tikhonov method was stable with Gaussian noise levels up to 20% and 10% change in stomach size. The use of 204 rather than 84 body surface electrodes improved the performance; however, for all investigated cases, the Greensite-Tikhonov method outperformed the Tikhonov method.

  16. ELECTRIC CURRENT FILAMENTATION AT A NON-POTENTIAL MAGNETIC NULL-POINT DUE TO PRESSURE PERTURBATION

    SciTech Connect

    Jelínek, P.; Karlický, M.; Murawski, K.

    2015-10-20

    An increase of electric current densities due to filamentation is an important process in any flare. We show that the pressure perturbation, followed by an entropy wave, triggers such a filamentation in the non-potential magnetic null-point. In the two-dimensional (2D), non-potential magnetic null-point, we generate the entropy wave by a negative or positive pressure pulse that is launched initially. Then, we study its evolution under the influence of the gravity field. We solve the full set of 2D time dependent, ideal magnetohydrodynamic equations numerically, making use of the FLASH code. The negative pulse leads to an entropy wave with a plasma density greater than in the ambient atmosphere and thus this wave falls down in the solar atmosphere, attracted by the gravity force. In the case of the positive pressure pulse, the plasma becomes evacuated and the entropy wave propagates upward. However, in both cases, owing to the Rayleigh–Taylor instability, the electric current in a non-potential magnetic null-point is rapidly filamented and at some locations the electric current density is strongly enhanced in comparison to its initial value. Using numerical simulations, we find that entropy waves initiated either by positive or negative pulses result in an increase of electric current densities close to the magnetic null-point and thus the energy accumulated here can be released as nanoflares or even flares.

  17. Quantum Effects of Electric Fields and Potentials on Electron Motion: An Introduction to Theoretical and Practical Aspects

    ERIC Educational Resources Information Center

    Matteucci, G.

    2007-01-01

    In the so-called electric Aharonov-Bohm effect, a quantum interference pattern shift is produced when electrons move in an electric field free region but, at the same time, in the presence of a time-dependent electric potential. Analogous fringe shifts are observed in interference experiments where electrons, travelling through an electrostatic…

  18. Fast Electrical Potential from a Long-Lived, Long-Wavelength Photoproduct of Fly Visual Pigment

    PubMed Central

    Pak, William L.; Lidington, Kellie J.

    1974-01-01

    A rapid electrical potential, which we have named the M-potential, can be obtained from the Drosophila eye using a high energy flash stimulus. The potential can be elicited from the normal fly, but it is especially prominent in the mutant norp AP12 (a phototransduction mutant), particularly if the eye color pigments are genetically removed from the eye. Several lines of evidence suggest that the M-potential arises from photoexcitation of long-lived metarhodopsin. Photoexcitation of rhodopsin does not produce a comparable potential. The spectral sensitivity of the M-potential peaks at about 575 nm. The M-potential pigment (metarhodopsin) can be shown to photoconvert back and forth with a "silent pigment(s)" absorbing maximally at about 485 nm. The silent pigment presumably is rhodopsin. These results support the recent spectrophotometric findings that dipteran metarhodopsin absorbs at much longer wavelengths than rhodopsin. The M-potential probably is related to the photoproduct component of the early receptor potential (ERP). Two major differences between the M-potential and the classical ERP are: (a) Drosophila rhodopsin does not produce a rapid photoresponse, and (b) an anesthetized or freshly sacrificed animal does not yield the M-potential. As in the case of the ERP, the M-potential appears to be a response associated with a particular state of the fly visual pigment. Therefore, it should be useful in in vivo investigations of the fly visual pigment, about which little is known. PMID:4829527

  19. European transition to a low carbon electricity system using a mix of variable renewable energies: carbon saving trajectories as functions of production and storage capacity.

    NASA Astrophysics Data System (ADS)

    Francois, Baptiste; Creutin, Jean-Dominique

    2016-04-01

    Today, most of the produced energy is generated from fossil energy sources (i.e. coal, petroleum). As a result, the energy sector is still the main source of greenhouse gas in the atmosphere. For limiting greenhouse gas emission, a transition from fossil to renewable energy is required, increasing gradually the fraction energy coming from variable renewable energy (i.e. solar power, wind power and run-of-the river hydropower, hereafter denoted as VRE). VRE penetration, i.e. the percentage of demand satisfied by variable renewables assuming no storage capacity, is hampered by their variable and un-controllable features. Many studies show that combining different VRE over space smoothes their variability and increases their global penetration by a better match of demand fluctuations. When the demand is not fully supplied by the VRE generation, backup generation is required from stored energy (mostly from dams) or fossil sources, the latter being associated with high greenhouse gas emission. Thus the VRE penetration is a direct indicator of carbon savings and basically depends on the VRE installed capacity, its mix features, and on the installed storage capacity. In this study we analyze the European transition to a low carbon electricity system. Over a selection of representative regions we analyze carbon saving trajectories as functions of VRE production and storage capacities for different scenarios mixing one to three VRE with non-renewables. We show substantial differences between trajectories when the mix of sources is far from the local optimums, when the storage capacity evolves. We bring new elements of reflection about the effect of transport grid features from local independent systems to a European "copper plate". This work is part of the FP7 project COMPLEX (Knowledge based climate mitigation systems for a low carbon economy; Project FP7-ENV-2012 number: 308601; http://www.complex.ac.uk/).

  20. Modulation of electrical potential and conductivity in an atomic-layer semiconductor heterojunction.

    PubMed

    Kobayashi, Yu; Yoshida, Shoji; Sakurada, Ryuji; Takashima, Kengo; Yamamoto, Takahiro; Saito, Tetsuki; Konabe, Satoru; Taniguchi, Takashi; Watanabe, Kenji; Maniwa, Yutaka; Takeuchi, Osamu; Shigekawa, Hidemi; Miyata, Yasumitsu

    2016-01-01

    Semiconductor heterojunction interfaces have been an important topic, both in modern solid state physics and in electronics and optoelectronics applications. Recently, the heterojunctions of atomically-thin transition metal dichalcogenides (TMDCs) are expected to realize one-dimensional (1D) electronic systems at their heterointerfaces due to their tunable electronic properties. Herein, we report unique conductivity enhancement and electrical potential modulation of heterojunction interfaces based on TMDC bilayers consisted of MoS2 and WS2. Scanning tunneling microscopy/spectroscopy analyses showed the formation of 1D confining potential (potential barrier) in the valence (conduction) band, as well as bandgap narrowing around the heterointerface. The modulation of electronic properties were also probed as the increase of current in conducting atomic force microscopy. Notably, the observed band bending can be explained by the presence of 1D fixed charges around the heterointerface. The present findings indicate that the atomic layer heterojunctions provide a novel approach to realizing tunable 1D electrical potential for embedded quantum wires and ultrashort barriers of electrical transport. PMID:27515115

  1. Modulation of electrical potential and conductivity in an atomic-layer semiconductor heterojunction

    PubMed Central

    Kobayashi, Yu; Yoshida, Shoji; Sakurada, Ryuji; Takashima, Kengo; Yamamoto, Takahiro; Saito, Tetsuki; Konabe, Satoru; Taniguchi, Takashi; Watanabe, Kenji; Maniwa, Yutaka; Takeuchi, Osamu; Shigekawa, Hidemi; Miyata, Yasumitsu

    2016-01-01

    Semiconductor heterojunction interfaces have been an important topic, both in modern solid state physics and in electronics and optoelectronics applications. Recently, the heterojunctions of atomically-thin transition metal dichalcogenides (TMDCs) are expected to realize one-dimensional (1D) electronic systems at their heterointerfaces due to their tunable electronic properties. Herein, we report unique conductivity enhancement and electrical potential modulation of heterojunction interfaces based on TMDC bilayers consisted of MoS2 and WS2. Scanning tunneling microscopy/spectroscopy analyses showed the formation of 1D confining potential (potential barrier) in the valence (conduction) band, as well as bandgap narrowing around the heterointerface. The modulation of electronic properties were also probed as the increase of current in conducting atomic force microscopy. Notably, the observed band bending can be explained by the presence of 1D fixed charges around the heterointerface. The present findings indicate that the atomic layer heterojunctions provide a novel approach to realizing tunable 1D electrical potential for embedded quantum wires and ultrashort barriers of electrical transport. PMID:27515115

  2. Modulation of electrical potential and conductivity in an atomic-layer semiconductor heterojunction

    NASA Astrophysics Data System (ADS)

    Kobayashi, Yu; Yoshida, Shoji; Sakurada, Ryuji; Takashima, Kengo; Yamamoto, Takahiro; Saito, Tetsuki; Konabe, Satoru; Taniguchi, Takashi; Watanabe, Kenji; Maniwa, Yutaka; Takeuchi, Osamu; Shigekawa, Hidemi; Miyata, Yasumitsu

    2016-08-01

    Semiconductor heterojunction interfaces have been an important topic, both in modern solid state physics and in electronics and optoelectronics applications. Recently, the heterojunctions of atomically-thin transition metal dichalcogenides (TMDCs) are expected to realize one-dimensional (1D) electronic systems at their heterointerfaces due to their tunable electronic properties. Herein, we report unique conductivity enhancement and electrical potential modulation of heterojunction interfaces based on TMDC bilayers consisted of MoS2 and WS2. Scanning tunneling microscopy/spectroscopy analyses showed the formation of 1D confining potential (potential barrier) in the valence (conduction) band, as well as bandgap narrowing around the heterointerface. The modulation of electronic properties were also probed as the increase of current in conducting atomic force microscopy. Notably, the observed band bending can be explained by the presence of 1D fixed charges around the heterointerface. The present findings indicate that the atomic layer heterojunctions provide a novel approach to realizing tunable 1D electrical potential for embedded quantum wires and ultrashort barriers of electrical transport.

  3. Modulation of electrical potential and conductivity in an atomic-layer semiconductor heterojunction.

    PubMed

    Kobayashi, Yu; Yoshida, Shoji; Sakurada, Ryuji; Takashima, Kengo; Yamamoto, Takahiro; Saito, Tetsuki; Konabe, Satoru; Taniguchi, Takashi; Watanabe, Kenji; Maniwa, Yutaka; Takeuchi, Osamu; Shigekawa, Hidemi; Miyata, Yasumitsu

    2016-08-12

    Semiconductor heterojunction interfaces have been an important topic, both in modern solid state physics and in electronics and optoelectronics applications. Recently, the heterojunctions of atomically-thin transition metal dichalcogenides (TMDCs) are expected to realize one-dimensional (1D) electronic systems at their heterointerfaces due to their tunable electronic properties. Herein, we report unique conductivity enhancement and electrical potential modulation of heterojunction interfaces based on TMDC bilayers consisted of MoS2 and WS2. Scanning tunneling microscopy/spectroscopy analyses showed the formation of 1D confining potential (potential barrier) in the valence (conduction) band, as well as bandgap narrowing around the heterointerface. The modulation of electronic properties were also probed as the increase of current in conducting atomic force microscopy. Notably, the observed band bending can be explained by the presence of 1D fixed charges around the heterointerface. The present findings indicate that the atomic layer heterojunctions provide a novel approach to realizing tunable 1D electrical potential for embedded quantum wires and ultrashort barriers of electrical transport.

  4. Evaluation of selected potential electric utility opportunities associated with rechargeable battery use. Final report

    SciTech Connect

    Barnett, B.

    1998-07-01

    This report offers a look at key market segments in rechargeable batteries and discusses trends in small cell and non-road vehicle battery technologies. The report provides numerous tables that offer a quick view of the worldwide rechargeable battery market today and its potential for future development, given specifically targeted promotional efforts. Models project that the 1998 total US annual electricity consumption associated with all small cell rechargeable batteries will be {approximately}187.9 million kWh or {approximately}$18.8 million (at $0.10/kWh). In this small cell market, notebook computer and cellular phone applications represented the largest electricity consumption. Due to the surprisingly small annual consumption, promotional efforts to increase small cell rechargeable battery use and associated electricity consumption cannot be considered to have adequate payback. Conversely, the 1996 total US annual electricity consumption of selected recharging non-road electric vehicles -- including lift trucks, golf cars, lawn mowers, floor care equipment, personnel/burden carriers, and airline ground support equipment applications -- was {approximately}3.02 billion kWh or {approximately}$301.5 million (at $0.10/kWh), about 16 times that associated with portable batteries. Because the battery associated with each of these applications is quite large and because the duty cycle for the use of these batteries is quite high, the electricity consumption associated with rechargeable battery-powered non-road electric vehicles appears to have much more impact than that of small cell portable applications. This study concludes that lift truck, golf car, and floor care equipment applications present the most promising promotional opportunities in this market.

  5. Surface plasmon resonance biomolecular recognition nanosystem: influence of the interfacial electrical potential.

    PubMed

    Lopatynskyi, Andrii; Guiver, Michael; Chegel, Volodymyr

    2014-09-01

    It is shown that the response of a surface plasmon resonance nanosystem designed according to Kretschmann geometry on the application of an external electric potential to the gold-electrolyte interface is well described by the proposed mathematical model, which takes into account the geometric surface imperfection and dependence of optical constants of the surface layer of gold film and capacitance of the electrical double layer on applied voltage. This model allows the appropriate correction for results of electrochemical surface plasmon resonance measurements. The dependence of a value of biomolecules adsorption in a surface plasmon resonance nanosystem on applied electric potential is shown for the first time. It is found that a shift of surface plasmon resonance angular position (Δθ(SPR)) and a change of capacitance of electrical double layer on the surface of gold (ΔC(dl)) for the adsorption of proteins under applied voltage are related to the nonlinear dependence Δθ(SPR) = (a + b x ΔC(dl))(-1). This phenomenon can be exploited in biochemical analysis to monitor the interaction of biomolecules, enhance response of biosensors, block unwanted adsorption, etc.

  6. [Electric reactive potentials to events with a positive and negative coloring in patients with protracted depression].

    PubMed

    Kurnitskaia, I V; Dmitriev, A S

    1987-01-01

    The authors measured electrical reactive potentials in the posterior associative and frontal areas, originating in response to winning or losing of the serve in tennis game shown on the video which served as a model of positive and negative emotional reactions. The studied potentials consisted of four waves: P300, N600, P800 and N1000. Healthy subjects experiencing positive emotions showed a more marked negative nature of the potentials in the left posterior associative zone while negative emotions were associated with the presence of predominantly negative potentials in the right frontal area. Patients with protracted depression presented a negative shift of potentials in both right posterior associative zone and left frontal area. The results obtained indicate that protracted depression is attended by impaired topography of the cortical processes associated with positive and negative emotions. PMID:3591142

  7. Influence of fixed electric charges on potential profile across the squid axon membrane

    NASA Astrophysics Data System (ADS)

    Cortez, C. M.; Cruz, F. A. O.; Silva, D.; Costa, L. F.

    2008-03-01

    The potential profile for a model of squid axon membrane has been determined for two physiological states: resting and action states. The non-linear Poisson-Boltzmann equation has been solved by considering the volumetric charge densities due to charges dissolved in an electrolytic solution and fixed on both glycocalyx and cytoplasmatic proteins. Results showing the features of the potential profile along the outer electrolytic region are similar for both resting and action states. However, the potential fall along glycocalyx at action state is lower than at resting. A small variation in the Na + concentration drastically affects the surface membrane potentials and vice versa. We conclude that effects on the potential profile due to surface lipidic bilayer charge and contiguous electric double layers are more relevant than those provoked by fixed charges distributed along the cell cytoplasm.

  8. In-vitro suppression of metabolic activity in malignant human glioblastomas due to pulsed - low frequency electric potential exposures

    NASA Astrophysics Data System (ADS)

    Schlichting, Abby; Waynant, Ronald W.; Tata, Darrell B.

    2010-02-01

    The role of pulsed - low repetition frequency electric potential was investigated in suppressing the metabolic activities of aggressive human brain cancer cells. Twenty four hours post exposure the glioblastomas were found to be significantly inhibited in their metabolic activity. The findings herein reveal a near complete inhibition of glioblastoma's metabolic activity through selective applications of low frequency pulsed electric potentials.

  9. Electrical Retrieval of Living Microorganisms from Cryopreserved Marine Sponges Using a Potential-Controlled Electrode.

    PubMed

    Koyama, Sumihiro; Nishi, Shinro; Tokuda, Maki; Uemura, Moeka; Ishikawa, Yoichi; Seya, Takeshi; Chow, Seinen; Ise, Yuji; Hatada, Yuji; Fujiwara, Yoshihiro; Tsubouchi, Taishi

    2015-10-01

    The purpose of this study was to develop a novel electrical retrieval method (ER method) for living sponge-associated microorganisms from marine sponges frozen at -80 °C. A -0.3-V vs. Ag/AgCl constant potential applied for 2 h at 9 °C induced the attachment of the sponge-associated microorganisms to an indium tin oxide/glass (ITO) or a gallium-doped zinc oxide/glass (GZO) working electrode. The electrically attached microorganisms from homogenized Spirastrella insignis tissues had intact cell membranes and showed intracellular dehydrogenase activity. Dead microorganisms were not attracted to the electrode when the homogenized tissues were autoclaved for 15 min at 121 °C before use. The electrically attached microorganisms included cultivable microorganisms retrieved after detachment from the electrode by application of a 9-MHz sine-wave potential. Using the ER method, we obtained 32 phyla and 72 classes of bacteria and 3 archaea of Crenarchaeota thermoprotei, Marine Group I, and Thaumarchaeota incertae sedis from marine sponges S. insignis and Callyspongia confoederata. Employment of the ER method for extraction and purification of the living microorganisms holds potential of single-cell cultivation for genome, transcriptome, proteome, and metabolome analyses of bioactive compounds producing sponge-associated microorganisms. PMID:26242755

  10. Electrical Retrieval of Living Microorganisms from Cryopreserved Marine Sponges Using a Potential-Controlled Electrode.

    PubMed

    Koyama, Sumihiro; Nishi, Shinro; Tokuda, Maki; Uemura, Moeka; Ishikawa, Yoichi; Seya, Takeshi; Chow, Seinen; Ise, Yuji; Hatada, Yuji; Fujiwara, Yoshihiro; Tsubouchi, Taishi

    2015-10-01

    The purpose of this study was to develop a novel electrical retrieval method (ER method) for living sponge-associated microorganisms from marine sponges frozen at -80 °C. A -0.3-V vs. Ag/AgCl constant potential applied for 2 h at 9 °C induced the attachment of the sponge-associated microorganisms to an indium tin oxide/glass (ITO) or a gallium-doped zinc oxide/glass (GZO) working electrode. The electrically attached microorganisms from homogenized Spirastrella insignis tissues had intact cell membranes and showed intracellular dehydrogenase activity. Dead microorganisms were not attracted to the electrode when the homogenized tissues were autoclaved for 15 min at 121 °C before use. The electrically attached microorganisms included cultivable microorganisms retrieved after detachment from the electrode by application of a 9-MHz sine-wave potential. Using the ER method, we obtained 32 phyla and 72 classes of bacteria and 3 archaea of Crenarchaeota thermoprotei, Marine Group I, and Thaumarchaeota incertae sedis from marine sponges S. insignis and Callyspongia confoederata. Employment of the ER method for extraction and purification of the living microorganisms holds potential of single-cell cultivation for genome, transcriptome, proteome, and metabolome analyses of bioactive compounds producing sponge-associated microorganisms.

  11. Assessment of Interval Data and Their Potential Application to Residential Electricity End-Use Modeling, An

    EIA Publications

    2015-01-01

    The Energy Information Administration (EIA) is investigating the potential benefits of incorporating interval electricity data into its residential energy end use models. This includes interval smart meter and submeter data from utility assets and systems. It is expected that these data will play a significant role in informing residential energy efficiency policies in the future. Therefore, a long-term strategy for improving the RECS end-use models will not be complete without an investigation of the current state of affairs of submeter data, including their potential for use in the context of residential building energy modeling.

  12. Temporal evolution and electric potential structure of the auroral acceleration region from multispacecraft measurements

    NASA Astrophysics Data System (ADS)

    Forsyth, C.; Fazakerley, A. N.; Walsh, A. P.; Watt, C. E.; Garza, K.; Owen, C. J.; Constantinescu, D. O.; Dandouras, I. S.; Fornacon, K.; Lucek, E. A.; Marklund, G. T.; Sadeghi, S. S.; Khotyaintsev, Y. V.; Masson, A.; Doss, N.

    2013-12-01

    Bright aurorae can be excited by the acceleration of electrons into the atmosphere in violation of ideal magnetohydrodynamics. Modelling studies predict that the accelerating electric potential consists of electric double layers at the boundaries of an acceleration region but observations suggest that particle acceleration occurs throughout this region. Using multispacecraft observations from Cluster, we have examined two upward current regions on 14 December 2009. Our observations show that the potential difference below C4 and C3 changed by up to 1.7 kV between their respective crossings, which were separated by 150 s. The field-aligned current density observed by C3 was also larger than that observed by C4. The potential drop above C3 and C4 was approximately the same in both crossings. Using a novel technique of quantitively comparing the electron spectra measured by Cluster 1 and 3, which were separated in altitude, we determine when these spacecraft made effectively magnetically conjugate observations, and we use these conjugate observations to determine the instantaneous distribution of the potential drop in the AAR. Our observations show that an average of 15% of the potential drop in the AAR was located between C1 at 6235 km and C3 at 4685 km altitude, with a maximum potential drop between the spacecraft of 500 V, and that the majority of the potential drop was below C3. Assuming a spatial invariance along the length of the upward current region, we discuss these observations in terms of temporal changes and the vertical structure of the electrostatic potential drop and in the context of existing models and previous single- and multispacecraft observations.

  13. Temporal evolution and electric potential structure of the auroral acceleration region from multispacecraft measurements

    NASA Astrophysics Data System (ADS)

    Forsyth, C.; Fazakerley, A. N.; Walsh, A. P.; Watt, C. E. J.; Garza, K. J.; Owen, C. J.; Constantinescu, D.; Dandouras, I.; FornaçOn, K.-H.; Lucek, E.; Marklund, G. T.; Sadeghi, S. S.; Khotyaintsev, Y.; Masson, A.; Doss, N.

    2012-12-01

    Bright aurorae can be excited by the acceleration of electrons into the atmosphere in violation of ideal magnetohydrodynamics. Modeling studies predict that the accelerating electric potential consists of electric double layers at the boundaries of an acceleration region but observations suggest that particle acceleration occurs throughout this region. Using multispacecraft observations from Cluster, we have examined two upward current regions on 14 December 2009. Our observations show that the potential difference below C4 and C3 changed by up to 1.7 kV between their respective crossings, which were separated by 150 s. The field-aligned current density observed by C3 was also larger than that observed by C4. The potential drop above C3 and C4 was approximately the same in both crossings. Using a novel technique of quantitively comparing the electron spectra measured by Cluster 1 and 3, which were separated in altitude, we determine when these spacecraft made effectively magnetically conjugate observations, and we use these conjugate observations to determine the instantaneous distribution of the potential drop in the AAR. Our observations show that an average of 15% of the potential drop in the AAR was located between C1 at 6235 km and C3 at 4685 km altitude, with a maximum potential drop between the spacecraft of 500 V, and that the majority of the potential drop was below C3. Assuming a spatial invariance along the length of the upward current region, we discuss these observations in terms of temporal changes and the vertical structure of the electrostatic potential drop and in the context of existing models and previous single- and multispacecraft observations.

  14. Potential reuse of small household waste electrical and electronic equipment: Methodology and case study.

    PubMed

    Bovea, María D; Ibáñez-Forés, Valeria; Pérez-Belis, Victoria; Quemades-Beltrán, Pilar

    2016-07-01

    This study proposes a general methodology for assessing and estimating the potential reuse of small waste electrical and electronic equipment (sWEEE), focusing on devices classified as domestic appliances. Specific tests for visual inspection, function and safety have been defined for ten different types of household appliances (vacuum cleaner, iron, microwave, toaster, sandwich maker, hand blender, juicer, boiler, heater and hair dryer). After applying the tests, reuse protocols have been defined in the form of easy-to-apply checklists for each of the ten types of appliance evaluated. This methodology could be useful for reuse enterprises, since there is a lack of specific protocols, adapted to each type of appliance, to test its potential of reuse. After applying the methodology, electrical and electronic appliances (used or waste) can be segregated into three categories: the appliance works properly and can be classified as direct reuse (items can be used by a second consumer without prior repair operations), the appliance requires a later evaluation of its potential refurbishment and repair (restoration of products to working order, although with possible loss of quality) or the appliance needs to be finally discarded from the reuse process and goes directly to a recycling process. Results after applying the methodology to a sample of 87.7kg (96 units) show that 30.2% of the appliances have no potential for reuse and should be diverted for recycling, while 67.7% require a subsequent evaluation of their potential refurbishment and repair, and only 2.1% of them could be directly reused with minor cleaning operations. This study represents a first approach to the "preparation for reuse" strategy that the European Directive related to Waste Electrical and Electronic Equipment encourages to be applied. However, more research needs to be done as an extension of this study, mainly related to the identification of the feasibility of repair or refurbishment operations.

  15. Potential reuse of small household waste electrical and electronic equipment: Methodology and case study.

    PubMed

    Bovea, María D; Ibáñez-Forés, Valeria; Pérez-Belis, Victoria; Quemades-Beltrán, Pilar

    2016-07-01

    This study proposes a general methodology for assessing and estimating the potential reuse of small waste electrical and electronic equipment (sWEEE), focusing on devices classified as domestic appliances. Specific tests for visual inspection, function and safety have been defined for ten different types of household appliances (vacuum cleaner, iron, microwave, toaster, sandwich maker, hand blender, juicer, boiler, heater and hair dryer). After applying the tests, reuse protocols have been defined in the form of easy-to-apply checklists for each of the ten types of appliance evaluated. This methodology could be useful for reuse enterprises, since there is a lack of specific protocols, adapted to each type of appliance, to test its potential of reuse. After applying the methodology, electrical and electronic appliances (used or waste) can be segregated into three categories: the appliance works properly and can be classified as direct reuse (items can be used by a second consumer without prior repair operations), the appliance requires a later evaluation of its potential refurbishment and repair (restoration of products to working order, although with possible loss of quality) or the appliance needs to be finally discarded from the reuse process and goes directly to a recycling process. Results after applying the methodology to a sample of 87.7kg (96 units) show that 30.2% of the appliances have no potential for reuse and should be diverted for recycling, while 67.7% require a subsequent evaluation of their potential refurbishment and repair, and only 2.1% of them could be directly reused with minor cleaning operations. This study represents a first approach to the "preparation for reuse" strategy that the European Directive related to Waste Electrical and Electronic Equipment encourages to be applied. However, more research needs to be done as an extension of this study, mainly related to the identification of the feasibility of repair or refurbishment operations

  16. Remote Sensing of Surface Electric Potential on the Moon: A New Technique Using ENAs for Future Missions

    NASA Astrophysics Data System (ADS)

    Futaana, Y.; Barabash, S.; Wieser, M.

    2013-09-01

    Electric potential at lunar surface provides essential information for understanding fundamental science and environment of the Moon, which directly impacts on future lunar exploration. Here we present a new technique of remote sensing of surface electric potential at the Moon [4]. The technique relies on the energy spectra of the energetic neutral atoms (ENAs) backscattered from the Moon. We applied this technique to the existing dataset of ENAs, and created the first 2-D image of the electric potential distribution near a magnetic anomaly. The result revealed that the magnetized area provides a preferable landing site of the Moon, while strong surface potential exists.

  17. Cost-of-illness analysis reveals potential healthcare savings with reductions in type 2 diabetes and cardiovascular disease following recommended intakes of dietary fiber in Canada

    PubMed Central

    Abdullah, Mohammad M. H.; Gyles, Collin L.; Marinangeli, Christopher P. F.; Carlberg, Jared G.; Jones, Peter J. H.

    2015-01-01

    Background: Type 2 diabetes (T2D) and cardiovascular disease (CVD) are leading causes of mortality and two of the most costly diet-related ailments worldwide. Consumption of fiber-rich diets has been repeatedly associated with favorable impacts on these co-epidemics, however, the healthcare cost-related economic value of altered dietary fiber intakes remains poorly understood. In this study, we estimated the annual cost savings accruing to the Canadian healthcare system in association with reductions in T2D and CVD rates, separately, following increased intakes of dietary fiber by adults. Methods: A three-step cost-of-illness analysis was conducted to identify the percentage of individuals expected to consume fiber-rich diets in Canada, estimate increased fiber intakes in relation to T2D and CVD reduction rates, and independently assess the potential annual savings in healthcare costs associated with the reductions in rates of these two epidemics. The economic model employed a sensitivity analysis of four scenarios (universal, optimistic, pessimistic, and very pessimistic) to cover a range of assumptions within each step. Results: Non-trivial healthcare and related savings of CAD$35.9-$718.8 million in T2D costs and CAD$64.8 million–$1.3 billion in CVD costs were calculated under a scenario where cereal fiber was used to increase current intakes of dietary fiber to the recommended levels of 38 g per day for men and 25 g per day for women. Each 1 g per day increase in fiber consumption resulted in annual CAD$2.6 to $51.1 million savings for T2D and $4.6 to $92.1 million savings for CVD. Conclusion: Findings of this analysis shed light on the economic value of optimal dietary fiber intakes. Strategies to increase consumers’ general knowledge of the recommended intakes of dietary fiber, as part of healthy diet, and to facilitate stakeholder synergy are warranted to enable better management of healthcare and related costs associated with T2D and CVD in Canada. PMID

  18. New porous medium Poisson-Nernst-Planck equations for strongly oscillating electric potentials

    NASA Astrophysics Data System (ADS)

    Schmuck, M.

    2013-02-01

    We consider the Poisson-Nernst-Planck system which is well-accepted for describing dilute electrolytes as well as transport of charged species in homogeneous environments. Here, we study these equations in porous media whose electric permittivities show a strong contrast compared with the electric permittivity of the electrolyte phase. Our main result is the derivation of convenient low-dimensional equations, that is, of effective macroscopic porous media Poisson-Nernst-Planck equations, which reliably describe ionic transport. The contrast in the electric permittivities between liquid and solid phase and the heterogeneity of the porous medium induce strongly oscillating electric potentials (fields). In order to account for this specific physical scenario, we introduce a modified asymptotic multiple-scale expansion which takes advantage of the nonlinearly coupled structure of the ionic transport equations. This allows for a systematic upscaling resulting in a new effective porous medium formulation which shows a new transport term on the macroscale. Solvability of all arising equations is rigorously verified. The emergence of a new transport term indicates promising physical insights into the influence of the microscale material properties on the macroscale. Hence, systematic upscaling strategies provide a source and a prospective tool to capitalize intrinsic scale effects for scientific, engineering, and industrial applications.

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

    SciTech Connect

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

    2000-01-01

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

  20. Profiling the Built-in Electrical Potential in III-V Multijunction Solar Cells: Preprint

    SciTech Connect

    Jiang, C.-S.; Friedman, D. J.; Moutinho, H. R.; Al-Jassim, M. M.

    2006-05-01

    We report on a direct measurement of the electrical potential on cross-sections of GaInP2/GaAs multiple-junction solar cells by using an ultrahigh-vacuum scanning Kelvin probe microscope (UHV-SKPM). The UHV-SKPM allows us to measure the potential without air molecules being adsorbed on the cross-sectional surface. Moreover, it uses a GaAs laser with photon energy of 1.4 eV for the atomic force microscope (AFM) operation. This eliminated the light-absorption-induced bottom-junction flattening and top-junction enhancement, which happened in our previous potential measurement using a 1.85-eV laser for the AFM operation. Three potentials were measured at the top, tunneling, and bottom junctions. Values of the potentials are smaller than the potentials in the bulk. This indicates that the Fermi level on the UHV-cleaved (110) surface was pinned, presumably due to defects upon cleaving. We also observed higher potentials at atomic steps than on the terraces for both GaInP2 epitaxial layer and GaAs substrate. Combining scanning tunneling microscopy (STM) and SKPM measurements, we found that the potential height at steps of the GaAs substrate depends on the step direction, which is probably a direct result of unbalanced cations and anions at the steps.

  1. Use of electrical impedance spectroscopy to detect malignant and potentially malignant oral lesions

    PubMed Central

    Murdoch, Craig; Brown, Brian H; Hearnden, Vanessa; Speight, Paul M; D’Apice, Katy; Hegarty, Anne M; Tidy, John A; Healey, T Jamie; Highfield, Peter E; Thornhill, Martin H

    2014-01-01

    The electrical properties of tissues depend on their architecture and cellular composition. We have previously shown that changes in electrical impedance can be used to differentiate between different degrees of cervical dysplasia and cancer of the cervix. In this proof-of-concept study, we aimed to determine whether electrical impedance spectroscopy (EIS) could distinguish between normal oral mucosa; benign, potentially malignant lesions (PML); and oral cancer. EIS data were collected from oral cancer (n=10), PML (n=27), and benign (n=10) lesions. EIS from lesions was compared with the EIS reading from the normal mucosa on the contralateral side of the mouth or with reference spectra from mucosal sites of control subjects (n=51). Healthy controls displayed significant differences in the EIS obtained from different oral sites. In addition, there were significant differences in the EIS of cancer and high-risk PML versus low-risk PML and controls. There was no significant difference between benign lesions and normal controls. Study subjects also deemed the EIS procedure considerably less painful and more convenient than the scalpel biopsy procedure. EIS shows promise at distinguishing among malignant, PML, and normal oral mucosa and has the potential to be developed into a clinical diagnostic tool. PMID:25285005

  2. Controlling trapping potentials and stray electric fields in a microfabricated ion trap through design and compensation

    NASA Astrophysics Data System (ADS)

    Doret, S. Charles; Amini, Jason M.; Wright, Kenneth; Volin, Curtis; Killian, Tyler; Ozakin, Arkadas; Denison, Douglas; Hayden, Harley; Pai, C.-S.; Slusher, Richart E.; Harter, Alexa W.

    2012-07-01

    Recent advances in quantum information processing with trapped ions have demonstrated the need for new ion trap architectures capable of holding and manipulating chains of many (>10) ions. Here we present the design and detailed characterization of a new linear trap, microfabricated with scalable complementary metal-oxide-semiconductor (CMOS) techniques, that is well-suited to this challenge. Forty-four individually controlled dc electrodes provide the many degrees of freedom required to construct anharmonic potential wells, shuttle ions, merge and split ion chains, precisely tune secular mode frequencies, and adjust the orientation of trap axes. Microfabricated capacitors on dc electrodes suppress radio-frequency pickup and excess micromotion, while a top-level ground layer simplifies modeling of electric fields and protects trap structures underneath. A localized aperture in the substrate provides access to the trapping region from an oven below, permitting deterministic loading of particular isotopic/elemental sequences via species-selective photoionization. The shapes of the aperture and radio-frequency electrodes are optimized to minimize perturbation of the trapping pseudopotential. Laboratory experiments verify simulated potentials and characterize trapping lifetimes, stray electric fields, and ion heating rates, while measurement and cancellation of spatially-varying stray electric fields permits the formation of nearly-equally spaced ion chains.

  3. Electrical Identification and Selective Microstimulation of Neuronal Compartments Based on Features of Extracellular Action Potentials

    PubMed Central

    Radivojevic, Milos; Jäckel, David; Altermatt, Michael; Müller, Jan; Viswam, Vijay; Hierlemann, Andreas; Bakkum, Douglas J.

    2016-01-01

    A detailed, high-spatiotemporal-resolution characterization of neuronal responses to local electrical fields and the capability of precise extracellular microstimulation of selected neurons are pivotal for studying and manipulating neuronal activity and circuits in networks and for developing neural prosthetics. Here, we studied cultured neocortical neurons by using high-density microelectrode arrays and optical imaging, complemented by the patch-clamp technique, and with the aim to correlate morphological and electrical features of neuronal compartments with their responsiveness to extracellular stimulation. We developed strategies to electrically identify any neuron in the network, while subcellular spatial resolution recording of extracellular action potential (AP) traces enabled their assignment to the axon initial segment (AIS), axonal arbor and proximal somatodendritic compartments. Stimulation at the AIS required low voltages and provided immediate, selective and reliable neuronal activation, whereas stimulation at the soma required high voltages and produced delayed and unreliable responses. Subthreshold stimulation at the soma depolarized the somatic membrane potential without eliciting APs. PMID:27510732

  4. Effect of electrical potential on the electro-demulsification of oily sludge.

    PubMed

    Elektorowicz, Maria; Habibi, Shiva; Chifrina, Rozalia

    2006-03-15

    Oily sludge, produced mostly in petroleum refineries and petrochemical industries, is one of the major industrial wastes that require treatment. Typically, these sludge wastes are water-in-oil emulsions that are stabilized by fine solids. These fine particles adsorb at the droplet surface and by lowering the demulsification rate constant, act as a barrier to prevent droplet coalescence. In this investigation, the effects of different electrical potential gradients and amphoteric surfactant on effectiveness of phase separation were investigated. It was concluded that lower electrical potential (0.5 V/cm) produced a higher demulsification rate. The solid phase remaining after the experiment was of a more compact and stable consistency. It was concluded that application of the amphoteric surfactant does not improve the total efficiency of the process. The role of oil constituents in stabilizing water-in-oil emulsions, and their effect on the dynamics of the process, were considered in every step of the experiment. Analysis of pH changes, resistance evolution, and hydrocarbon polarity analysis confirmed that the application of lower electrical gradient results in better phase separation.

  5. The induction of reentry in cardiac tissue. The missing link: How electric fields alter transmembrane potential

    NASA Astrophysics Data System (ADS)

    Roth, Bradley J.; Krassowska, Wanda

    1998-03-01

    This review examines the initiation of reentry in cardiac muscle by strong electric shocks. Specifically, it concentrates on the mechanisms by which electric shocks change the transmembrane potential of the cardiac membrane and create the physiological substrate required by the critical point theory for the initiation of rotors. The mechanisms examined include (1) direct polarization of the tissue by the stimulating current, as described by the one-dimensional cable model and its two- and three-dimensional extensions, (2) the presence of virtual anodes and cathodes, as described by the bidomain model with unequal anisotropy ratios of the intra- and extracellular spaces, (3) polarization of the tissue due to changing orientation of cardiac fibers, and (4) polarization of individual cells or groups of cells by the electric field ("sawtooth potential"). The importance of these mechanisms in the initiation of reentry is examined in two case studies: the induction of rotors using successive stimulation with a unipolar electrode, and the induction of rotors using cross-field stimulation. These cases reveal that the mechanism by which a unipolar stimulation induces arrhythmias can be explained in the framework of the bidomain model with unequal anisotropy ratios. In contrast, none of the examined mechanisms provide an adequate explanation for the induction of rotors by cross-field stimulation. Hence, this study emphasizes the need for further experimental and theoretical work directed toward explaining the mechanism of field stimulation.

  6. Electrical Identification and Selective Microstimulation of Neuronal Compartments Based on Features of Extracellular Action Potentials.

    PubMed

    Radivojevic, Milos; Jäckel, David; Altermatt, Michael; Müller, Jan; Viswam, Vijay; Hierlemann, Andreas; Bakkum, Douglas J

    2016-01-01

    A detailed, high-spatiotemporal-resolution characterization of neuronal responses to local electrical fields and the capability of precise extracellular microstimulation of selected neurons are pivotal for studying and manipulating neuronal activity and circuits in networks and for developing neural prosthetics. Here, we studied cultured neocortical neurons by using high-density microelectrode arrays and optical imaging, complemented by the patch-clamp technique, and with the aim to correlate morphological and electrical features of neuronal compartments with their responsiveness to extracellular stimulation. We developed strategies to electrically identify any neuron in the network, while subcellular spatial resolution recording of extracellular action potential (AP) traces enabled their assignment to the axon initial segment (AIS), axonal arbor and proximal somatodendritic compartments. Stimulation at the AIS required low voltages and provided immediate, selective and reliable neuronal activation, whereas stimulation at the soma required high voltages and produced delayed and unreliable responses. Subthreshold stimulation at the soma depolarized the somatic membrane potential without eliciting APs. PMID:27510732

  7. Visual and noxious electrical stimulus-evoked membrane-potential responses in anterior cingulate cortical neurons.

    PubMed

    Ma, Li-Qing; Ning, Li; Wang, Zhiru; Wang, Ying-Wei

    2016-01-01

    Anterior cingulate cortex (ACC) is known to participate in numerous brain functions, such as memory storage, emotion, attention, as well as perception of acute and chronic pain. ACC-dependent brain functions often rely on ACC processing of various forms of environmental information. To understand the neural basis of ACC functions, previous studies have investigated ACC responses to environmental stimulation, particularly complex sensory stimuli as well as award and aversive stimuli, but this issue remains to be further clarified. Here, by performing whole-cell recording in vivo in anaesthetized adult rats, we examined membrane-potential (MP) responses of layer II/III ACC neurons that were evoked by a brief flash of visual stimulation and pain-related electrical stimulation delivered to hind paws. We found that ~54 and ~81 % ACC neurons exhibited excitatory MP responses, subthreshold or suprathreshold, to the visual stimulus and the electrical stimulus, respectively, with no cell showing inhibitory MP responses. We further found that the visually evoked ACC response could be greatly diminished by local lidocaine infusion in the visual thalamus, and only their temporal patterns but not amplitudes could be changed by large-scale visual cortical lesions. Our in vivo whole-cell recording data characterized in ACC neurons a visually evoked response, which was largely dependent on the visual thalamus but not visual cortex, as well as a noxious electrical stimulus-evoked response. These findings may provide potential mechanisms that are used for ACC functions on the basis of sensory information processing. PMID:27585569

  8. (Assessment of the potential of Yunnan Province, China to grow and convert biomass to electricity)

    SciTech Connect

    Perlack, R.D.

    1990-10-15

    The purpose of the trip was to conduct a preliminary evaluation of biomass energy development in Yunnan Province, China. The evaluation included an assessment of the potential to grow and convert biomass to electricity, and an evaluation of the institutional relationships, which would be critical to the establishment of a collaborative biomass energy development project. This site visit was undertaken to evaluate the potential of an integrated biomass energy project, including the growing and handling of biomass feedstocks and its conversion to electricity. Based on this site visit, it was concluded that biomass production risks are real and further research on species screening and experiments is necessary before proceeding to the conversion phase of this project. The location of potential sites inspected and the logistics required for handling and transporting biomass may also be a concern. The commitment of support (labor and land) and leadership to this project by the Chinese is overwhelming exceeding all pre-site visit expectations. In sum, there is a definite opportunity in Yunnan for an integrated biomass energy project and a potential market for US technology.

  9. Ion permeability of artificial membranes evaluated by diffusion potential and electrical resistance measurements.

    PubMed

    Shlyonsky, Vadim

    2013-12-01

    In the present article, a novel model of artificial membranes that provides efficient assistance in teaching the origins of diffusion potentials is proposed. These membranes are made of polycarbonate filters fixed to 12-mm plastic rings and then saturated with a mixture of creosol and n-decane. The electrical resistance and potential difference across these membranes can be easily measured using a low-cost volt-ohm meter and home-made Ag/AgCl electrodes. The advantage of the model is the lack of ionic selectivity of the membrane, which can be modified by the introduction of different ionophores to the organic liquid mixture. A membrane treated with the mixture containing valinomycin generates voltages from -53 to -25 mV in the presence of a 10-fold KCl gradient (in to out) and from -79 to -53 mV in the presence of a bi-ionic KCl/NaCl gradient (in to out). This latter bi-ionic gradient potential reverses to a value from +9 to +20 mV when monensin is present in the organic liquid mixture. Thus, the model can be build stepwise, i.e., all factors leading to the development of diffusion potentials can be introduced sequentially, helping students to understand the quantitative relationships of ionic gradients and differential membrane permeability in the generation of cell electrical signals.

  10. Electrical Potentials Observed During Frictional Stick-Slip - A Semiconductor Mechanism

    NASA Astrophysics Data System (ADS)

    Leeman, J.; Scuderi, M.; Marone, C.; Saffer, D. M.

    2013-12-01

    Electromagnetic phenomena are commonly reported during and after large earthquakes. Various lines of evidence including charring of plant roots, magnetic remnant signatures in pseudotachylite, and visible earthquake lights indicate a strong electrical potential separation during co-seismic rupture. Suggested explanations have included triboelectricity, piezoelectricity, and streaming potentials. The 'semiconductor effect', or migration of electron holes, has been proposed as an alternative explanation and studied extensively in solids. We present evidence of a similar migration effect in a granular material that exhibits repeated frictional stick-slip events under a variety of conditions. Soda-lime glass beads were sheared in a double-direct shear configuration in a biaxial loading frame. Glass beads exhibit consistent, repetitive stick-slip and rate/state friction effects that are similar to rock. Layers of 5 mm thickness were sheared under a constant normal load of 4MPa, at load point velocities of 1, 30, and 100 μm/s. This was done for mono-disperse particle size distributions of 100-150 μm and 420-500 μm. Tests were conducted at room humidity, at 100% humidity, and under submerged conditions. During shearing, the electrical potential of the surface was monitored relative to the system ground with a non-contact electrostatic volt meter (ESVM) manufactured by Trek Incorporated. During stick-slip events, we observe electrical potential anomalies that appear to be related to failure of force chains supporting the shear load. Two distinct types of behavior are delineated by the attainment of steady state frictional sliding. In the pre-steady state phase, as shear stress is increasing, layers are observed to charge during stick-slip and the potential of the entire system rises. When shear stress rises to the level of steady state frictional sliding, the system begins to discharge, with superimposed anomalies characterized by potential drops of several volts that

  11. Potential Impacts of Plug-in Hybrid Electric Vehicles on Regional Power Generation

    SciTech Connect

    Hadley, Stanton W; Tsvetkova, Alexandra A

    2008-01-01

    Plug-in hybrid electric vehicles (PHEVs) are being developed around the world, with much work aiming to optimize engine and battery for efficient operation, both during discharge and when grid electricity is available for recharging. However, the general expectation has been that the grid will not be greatly affected by the use of PHEVs because the recharging will occur during off-peak hours, or the number of vehicles will grow slowly enough so that capacity planning will respond adequately. This expectation does not consider that drivers will control the timing of recharging, and their inclination will be to plug in when convenient, rather than when utilities would prefer. It is important to understand the ramifications of adding load from PHEVs onto the grid. Depending on when and where the vehicles are plugged in, they could cause local or regional constraints on the grid. They could require the addition of new electric capacity and increase the utilization of existing capacity. Usage patterns of local distribution grids will change, and some lines or substations may become overloaded sooner than expected. Furthermore, the type of generation used to meet the demand for recharging PHEVs will depend on the region of the country and the timing of recharging. This paper analyzes the potential impacts of PHEVs on electricity demand, supply, generation structure, prices, and associated emission levels in 2020 and 2030 in 13 regions specified by the North American Electric Reliability Corporation (NERC) and the U.S. Department of Energy's (DOE's) Energy Information Administration (EIA), and on which the data and analysis in EIA's Annual Energy Outlook 2007 are based (Figure ES-1). The estimates of power plant supplies and regional hourly electricity demand come from publicly available sources from EIA and the Federal Energy Regulatory Commission. Electricity requirements for PHEVs are based on analysis from the Electric Power Research Institute, with an optimistic

  12. Investigating the performance and energy saving potential of Chinese commercial building benchmark models for the hot humid and severe cold climate regions

    NASA Astrophysics Data System (ADS)

    Herrmann, Lesley Anne

    2011-12-01

    The demand for energy in China is growing at an alarming rate. Buildings have become a significant component of the energy-demand mix accounting for nearly one-quarter of the country's total primary energy consumption. This study compares the building code standards for office and hotel buildings in the hot humid and severe cold climate regions of China and the United States. Benchmark office and hotel building models have been developed for Guangzhou and Harbin, China that meets China's minimum national and regional building energy codes with the integration of common design and construction practices for each region. These models are compared to the ASHRAE standard based US reference building models for Houston, Texas and Duluth, Minnesota which have similar climate conditions. The research further uses a building energy optimization tool to optimize the Chinese benchmarks using existing US products to identify the primary areas for potential energy savings. In the case of the Harbin models, an economic analysis has also been performed to determine the economic feasibility of alternative building designs. The most significant energy-saving options are then presented as recommendations for potential improvements to current China building energy codes.

  13. Reevaluation of Vitrified High-Level Waste Form Criteria for Potential Cost Savings at the Defense Waste Processing Facility - 13598

    SciTech Connect

    Ray, J.W.; Marra, S.L.; Herman, C.C.

    2013-07-01

    At the Savannah River Site (SRS) the Defense Waste Processing Facility (DWPF) has been immobilizing SRS's radioactive high level waste (HLW) sludge into a durable borosilicate glass since 1996. Currently the DWPF has poured over 3,500 canisters, all of which are compliant with the U. S. Department of Energy's (DOE) Waste Acceptance Product Specifications for Vitrified High-Level Waste Forms (WAPS) and therefore ready to be shipped to a federal geologic repository for permanent disposal. Due to DOE petitioning to withdraw the Yucca Mountain License Application (LA) from the Nuclear Regulatory Commission (NRC) in 2010 and thus no clear disposal path for SRS canistered waste forms, there are opportunities for cost savings with future canister production at DWPF and other DOE producer sites by reevaluating high-level waste form requirements and compliance strategies and reducing/eliminating those that will not negatively impact the quality of the canistered waste form. (authors)

  14. Reevaluation Of Vitrified High-Level Waste Form Criteria For Potential Cost Savings At The Defense Waste Processing Facility

    SciTech Connect

    Ray, J. W.; Marra, S. L.; Herman, C. C.

    2013-01-09

    At the Savannah River Site (SRS) the Defense Waste Processing Facility (DWPF) has been immobilizing SRS's radioactive high level waste (HLW) sludge into a durable borosilicate glass since 1996. Currently the DWPF has poured over 3,500 canisters, all of which are compliant with the U. S. Department of Energy's (DOE) Waste Acceptance Product Specifications for Vitrified High-Level Waste Forms (WAPS) and therefore ready to be shipped to a federal geologic repository for permanent disposal. Due to DOE petitioning to withdraw the Yucca Mountain License Application (LA) from the Nuclear Regulatory Commission (NRC) in 2010 and thus no clear disposal path for SRS canistered waste forms, there are opportunities for cost savings with future canister production at DWPF and other DOE producer sites by reevaluating high-level waste form requirements and compliance strategies and reducing/eliminating those that will not negatively impact the quality of the canistered waste form.

  15. Potential for steel industry energy intensity improvements: Electricity use in minimills

    SciTech Connect

    Boyd, G.; Neifer, M.; Karlson, S. |; Ross, M. |

    1992-09-01

    US steel manufacturing has experienced an extended episode of creative destruction in the past twenty years. The creative destruction has been the closure of over fifty million tons worth of annual capacity in iron-ore based steel plants concurrent with the construction of nearly thirty million tons of productive capacity in scrap-based steel plants. Our focus is on the effects of the creative destruction in steel on the use of electricity in steel manufacture. This paper utilizes the plant level data at the Center for Economic Studies at the Census to analyze the energy and technical efficiency of minimills from 1972 to 1988. We examine the potential for improvements in energy (electricity) use within the minimills segment of the industry. Since the role of this segment of the industry has changed so dramatically in the last 20 years we examine in detail the role that the plant age and vintage plays in determining energy and technical efficiency.

  16. Potential for steel industry energy intensity improvements: Electricity use in minimills

    SciTech Connect

    Boyd, G.; Neifer, M. ); Karlson, S. . Dept. of Economics Argonne National Lab., IL ); Ross, M. . Dept. of Physics Argonne National Lab., IL )

    1992-01-01

    US steel manufacturing has experienced an extended episode of creative destruction in the past twenty years. The creative destruction has been the closure of over fifty million tons worth of annual capacity in iron-ore based steel plants concurrent with the construction of nearly thirty million tons of productive capacity in scrap-based steel plants. Our focus is on the effects of the creative destruction in steel on the use of electricity in steel manufacture. This paper utilizes the plant level data at the Center for Economic Studies at the Census to analyze the energy and technical efficiency of minimills from 1972 to 1988. We examine the potential for improvements in energy (electricity) use within the minimills segment of the industry. Since the role of this segment of the industry has changed so dramatically in the last 20 years we examine in detail the role that the plant age and vintage plays in determining energy and technical efficiency.

  17. Transmembrane Potential Modeling: Comparison between Methods of Constant Electric Field and Ion Imbalance.

    PubMed

    Melcr, Josef; Bonhenry, Daniel; Timr, Štěpán; Jungwirth, Pavel

    2016-05-10

    Two approaches for modeling of the transmembrane potential, as present in all eukaryotic cells, are examined in detail and compared with each other. One approach uses an externally applied electric field, whereas the other maintains an imbalance of ions on the two sides of a membrane. We demonstrate that both methods provide converged results concerning structural parameters of the membrane which are practically indistinguishable from each other, at least for monovalent ions. Effects of the electric field on the detailed molecular structure of the phospholipid bilayer are also presented and discussed. In addition, we achieve a considerable speed-up of the underlying molecular dynamics simulations by implementing the virtual interaction sites method for the Slipids force field.

  18. Effect of Cardiac Tissue Anisotropy on Three-Dimensional Electrical Action Potential Propagation

    NASA Astrophysics Data System (ADS)

    He, Zhi Zhu; Liu, Jing

    A three-dimensional (3D) electrical action potential propagation model is developed to characterize the integrated effect of cardiac tissue structure using a homogenous function with a spatial inhomogeneity. This method may be more effective for bridging the gap between computational models and experimental data for cardiac tissue anisotropy. A generalized 3D eikonal relation considering anisotropy and a self-similar evolution solution of such a relation are derived to identify the effect of anisotropy and predict the anisotropy-induced electrical wave propagation instabilities. Furthermore, the phase field equation is introduced to obtain the complex three-dimensional numerical solution of the new correlation. The present results are expected to be valuable for better understanding the physiological behavior of cardiac tissues.

  19. Dispersion potential between three-bodies with arbitrary electric multipole polarizabilities: Molecular QED theory

    SciTech Connect

    Salam, A.

    2014-01-28

    Molecular quantum electrodynamics is used to obtain an expression for the retarded dispersion energy shift between three arbitrarily electrically polarizable atoms or molecules. A generalized Craig-Power Hamiltonian that depends quadratically on the electric displacement field is employed together with third-order diagrammatic perturbation theory. This approach simplifies the calculation relative to the use of the usual multipolar coupling Hamiltonian that is linear in the displacement field. Specific higher multipole non-additive contributions are then extracted. These include dipole-dipole-quadrupole, dipole-quadrupole-quadrupole, and dipole-dipole-octupole potentials valid for oriented and isotropic species with arbitrary separation distances between particles, extending recent work in which these energy shifts were given for equilateral triangle and collinear geometries. Near-zone limiting forms are found to agree with earlier works in which static inter-particle couplings were used.

  20. VO2 thermochromic smart window for energy savings and generation

    PubMed Central

    Zhou, Jiadong; Gao, Yanfeng; Zhang, Zongtao; Luo, Hongjie; Cao, Chuanxiang; Chen, Zhang; Dai, Lei; Liu, Xinling

    2013-01-01

    The ability to achieve energy saving in architectures and optimal solar energy utilisation affects the sustainable development of the human race. Traditional smart windows and solar cells cannot be combined into one device for energy saving and electricity generation. A VO2 film can respond to the environmental temperature to intelligently regulate infrared transmittance while maintaining visible transparency, and can be applied as a thermochromic smart window. Herein, we report for the first time a novel VO2-based smart window that partially utilises light scattering to solar cells around the glass panel for electricity generation. This smart window combines energy-saving and generation in one device, and offers potential to intelligently regulate and utilise solar radiation in an efficient manner. PMID:24157625

  1. VO₂ thermochromic smart window for energy savings and generation.

    PubMed

    Zhou, Jiadong; Gao, Yanfeng; Zhang, Zongtao; Luo, Hongjie; Cao, Chuanxiang; Chen, Zhang; Dai, Lei; Liu, Xinling

    2013-10-24

    The ability to achieve energy saving in architectures and optimal solar energy utilisation affects the sustainable development of the human race. Traditional smart windows and solar cells cannot be combined into one device for energy saving and electricity generation. A VO2 film can respond to the environmental temperature to intelligently regulate infrared transmittance while maintaining visible transparency, and can be applied as a thermochromic smart window. Herein, we report for the first time a novel VO2-based smart window that partially utilises light scattering to solar cells around the glass panel for electricity generation. This smart window combines energy-saving and generation in one device, and offers potential to intelligently regulate and utilise solar radiation in an efficient manner.

  2. VO₂ thermochromic smart window for energy savings and generation.

    PubMed

    Zhou, Jiadong; Gao, Yanfeng; Zhang, Zongtao; Luo, Hongjie; Cao, Chuanxiang; Chen, Zhang; Dai, Lei; Liu, Xinling

    2013-01-01

    The ability to achieve energy saving in architectures and optimal solar energy utilisation affects the sustainable development of the human race. Traditional smart windows and solar cells cannot be combined into one device for energy saving and electricity generation. A VO2 film can respond to the environmental temperature to intelligently regulate infrared transmittance while maintaining visible transparency, and can be applied as a thermochromic smart window. Herein, we report for the first time a novel VO2-based smart window that partially utilises light scattering to solar cells around the glass panel for electricity generation. This smart window combines energy-saving and generation in one device, and offers potential to intelligently regulate and utilise solar radiation in an efficient manner. PMID:24157625

  3. Modeling of the Through-the-Thickness Electric Potentials of a Piezoelectric Bimorph Using the Spectral Element Method

    PubMed Central

    Dong, Xingjian; Peng, Zhike; Hua, Hongxing; Meng, Guang

    2014-01-01

    An efficient spectral element (SE) with electric potential degrees of freedom (DOF) is proposed to investigate the static electromechanical responses of a piezoelectric bimorph for its actuator and sensor functions. A sublayer model based on the piecewise linear approximation for the electric potential is used to describe the nonlinear distribution of electric potential through the thickness of the piezoelectric layers. An equivalent single layer (ESL) model based on first-order shear deformation theory (FSDT) is used to describe the displacement field. The Legendre orthogonal polynomials of order 5 are used in the element interpolation functions. The validity and the capability of the present SE model for investigation of global and local responses of the piezoelectric bimorph are confirmed by comparing the present solutions with those obtained from coupled 3-D finite element (FE) analysis. It is shown that, without introducing any higher-order electric potential assumptions, the current method can accurately describe the distribution of the electric potential across the thickness even for a rather thick bimorph. It is revealed that the effect of electric potential is significant when the bimorph is used as sensor while the effect is insignificant when the bimorph is used as actuator, and therefore, the present study may provide a better understanding of the nonlinear induced electric potential for bimorph sensor and actuator. PMID:24561399

  4. Evaluation of the constant potential method in simulating electric double-layer capacitors

    NASA Astrophysics Data System (ADS)

    Wang, Zhenxing; Yang, Yang; Olmsted, David L.; Asta, Mark; Laird, Brian B.

    2014-11-01

    A major challenge in the molecular simulation of electric double layer capacitors (EDLCs) is the choice of an appropriate model for the electrode. Typically, in such simulations the electrode surface is modeled using a uniform fixed charge on each of the electrode atoms, which ignores the electrode response to local charge fluctuations in the electrolyte solution. In this work, we evaluate and compare this Fixed Charge Method (FCM) with the more realistic Constant Potential Method (CPM), [S. K. Reed et al., J. Chem. Phys. 126, 084704 (2007)], in which the electrode charges fluctuate in order to maintain constant electric potential in each electrode. For this comparison, we utilize a simplified LiClO4-acetonitrile/graphite EDLC. At low potential difference (ΔΨ ⩽ 2 V), the two methods yield essentially identical results for ion and solvent density profiles; however, significant differences appear at higher ΔΨ. At ΔΨ ⩾ 4 V, the CPM ion density profiles show significant enhancement (over FCM) of "inner-sphere adsorbed" Li+ ions very close to the electrode surface. The ability of the CPM electrode to respond to local charge fluctuations in the electrolyte is seen to significantly lower the energy (and barrier) for the approach of Li+ ions to the electrode surface.

  5. Evaluation of the constant potential method in simulating electric double-layer capacitors.

    PubMed

    Wang, Zhenxing; Yang, Yang; Olmsted, David L; Asta, Mark; Laird, Brian B

    2014-11-14

    A major challenge in the molecular simulation of electric double layer capacitors (EDLCs) is the choice of an appropriate model for the electrode. Typically, in such simulations the electrode surface is modeled using a uniform fixed charge on each of the electrode atoms, which ignores the electrode response to local charge fluctuations in the electrolyte solution. In this work, we evaluate and compare this Fixed Charge Method (FCM) with the more realistic Constant Potential Method (CPM), [S. K. Reed et al., J. Chem. Phys. 126, 084704 (2007)], in which the electrode charges fluctuate in order to maintain constant electric potential in each electrode. For this comparison, we utilize a simplified LiClO4-acetonitrile/graphite EDLC. At low potential difference (ΔΨ ⩽ 2 V), the two methods yield essentially identical results for ion and solvent density profiles; however, significant differences appear at higher ΔΨ. At ΔΨ ⩾ 4 V, the CPM ion density profiles show significant enhancement (over FCM) of "inner-sphere adsorbed" Li(+) ions very close to the electrode surface. The ability of the CPM electrode to respond to local charge fluctuations in the electrolyte is seen to significantly lower the energy (and barrier) for the approach of Li(+) ions to the electrode surface. PMID:25399127

  6. The Electrical Self-Potential Method as a Non-Intrusive Snow-Hydrological Sensor

    NASA Astrophysics Data System (ADS)

    Kulessa, B.; Thompson, S. S.; Luethi, M. P.; Essery, R.

    2015-12-01

    Building on growing momentum in the application of geophysical techniques to snow problems and, specifically, on new theory and an electrical geophysical snow hydrological model published recently; we demonstrate for the first time that the electrical self-potential geophysical technique can sense in-situ bulk meltwater fluxes. This has broad and immediate implications for snow measurement practice, modelling and operational snow forecasting. Our ability to measure, quantify and assimilate hydrological properties and processes of snow in operational models is disproportionally poor compared to the significance of seasonal snowmelt as a global water resource and major risk factor in flood and avalanche forecasting. Encouraged by recent theoretical, modelling and laboratory work, we show here that the diurnal evolution of aerially-distributed self-potential magnitudes closely track those of bulk meltwater fluxes in melting in-situ snowpacks at Rhone and Jungfraujoch glaciers, Switzerland. Numerical modelling infers temporally-evolving liquid water contents in the snowpacks on successive days in close agreement with snow-pit measurements. Muting previous concerns, the governing physical and chemical properties of snow and meltwater became temporally invariant for modelling purposes. Because measurement procedure is straightforward and readily automated for continuous monitoring over significant spatial scales, we conclude that the self-potential geophysical method is a highly-promising non-intrusive snow-hydrological sensor for measurement practice, modelling and operational snow forecasting.

  7. Evaluation of the constant potential method in simulating electric double-layer capacitors.

    PubMed

    Wang, Zhenxing; Yang, Yang; Olmsted, David L; Asta, Mark; Laird, Brian B

    2014-11-14

    A major challenge in the molecular simulation of electric double layer capacitors (EDLCs) is the choice of an appropriate model for the electrode. Typically, in such simulations the electrode surface is modeled using a uniform fixed charge on each of the electrode atoms, which ignores the electrode response to local charge fluctuations in the electrolyte solution. In this work, we evaluate and compare this Fixed Charge Method (FCM) with the more realistic Constant Potential Method (CPM), [S. K. Reed et al., J. Chem. Phys. 126, 084704 (2007)], in which the electrode charges fluctuate in order to maintain constant electric potential in each electrode. For this comparison, we utilize a simplified LiClO4-acetonitrile/graphite EDLC. At low potential difference (ΔΨ ⩽ 2 V), the two methods yield essentially identical results for ion and solvent density profiles; however, significant differences appear at higher ΔΨ. At ΔΨ ⩾ 4 V, the CPM ion density profiles show significant enhancement (over FCM) of "inner-sphere adsorbed" Li(+) ions very close to the electrode surface. The ability of the CPM electrode to respond to local charge fluctuations in the electrolyte is seen to significantly lower the energy (and barrier) for the approach of Li(+) ions to the electrode surface.

  8. Evaluation of the constant potential method in simulating electric double-layer capacitors

    SciTech Connect

    Wang, Zhenxing; Laird, Brian B.; Yang, Yang; Olmsted, David L.; Asta, Mark

    2014-11-14

    A major challenge in the molecular simulation of electric double layer capacitors (EDLCs) is the choice of an appropriate model for the electrode. Typically, in such simulations the electrode surface is modeled using a uniform fixed charge on each of the electrode atoms, which ignores the electrode response to local charge fluctuations in the electrolyte solution. In this work, we evaluate and compare this Fixed Charge Method (FCM) with the more realistic Constant Potential Method (CPM), [S. K. Reed et al., J. Chem. Phys. 126, 084704 (2007)], in which the electrode charges fluctuate in order to maintain constant electric potential in each electrode. For this comparison, we utilize a simplified LiClO{sub 4}-acetonitrile/graphite EDLC. At low potential difference (ΔΨ ⩽ 2 V), the two methods yield essentially identical results for ion and solvent density profiles; however, significant differences appear at higher ΔΨ. At ΔΨ ⩾ 4 V, the CPM ion density profiles show significant enhancement (over FCM) of “inner-sphere adsorbed” Li{sup +} ions very close to the electrode surface. The ability of the CPM electrode to respond to local charge fluctuations in the electrolyte is seen to significantly lower the energy (and barrier) for the approach of Li{sup +} ions to the electrode surface.

  9. 60 Hz electric field changes the membrane potential during burst phase in pancreatic β-cells: in silico analysis.

    PubMed

    Neves, Gesilda F; Silva, José R F; Moraes, Renato B; Fernandes, Thiago S; Tenorio, Bruno M; Nogueira, Romildo A

    2014-06-01

    The production, distribution and use of electricity can generate low frequency electric and magnetic fields (50-60 Hz). Considering that some studies showed adverse effects on pancreatic β-cells exposed to these fields; the present study aimed to analyze the effects of 60 Hz electric fields on membrane potential during the silent and burst phases in pancreatic β-cells using a mathematical model. Sinusoidal 60 Hz electric fields with amplitude ranging from 0.5 to 4 mV were applied on pancreatic β-cells model. The sinusoidal electric field changed burst duration, inter-burst intervals (silent phase) and spike sizes. The parameters above presented dose-dependent response with the voltage amplitude applied. In conclusion, theoretical analyses showed that a 60 Hz electric field with low amplitudes changes the membrane potential in pancreatic β-cells.

  10. Study of the cost-savings potential of the Military - Civilian Health Services Partnership Program in the nuclear medicine and radioimmunoassay services at Ireland Army Community Hospital, Fort Knox, Kentucky. Master's thesis, July 1987-July 1988

    SciTech Connect

    Amon, T.M.

    1989-01-01

    Using workload data for Calendar Year 1987, a cost savings analysis was performed on the following three options (involving the Nuclear Medicine Department at Ireland Army Community Hospital); (1) Elimination of Radioimmunoassay Internal Service, (2) Civilian Military Health Service Partnership Program and (3) Fixed price contract for Nuclear Medicine Services. This study revealed the Civilian-Military Health Services Partnership Program would potentially generate the greatest cost savings and recommended that it be implemented in other areas throughout the Army Medical Department.

  11. Potential Impact of the National Plan for Future Electric Power Supply on Air Quality in Korea

    NASA Astrophysics Data System (ADS)

    Shim, C.; Hong, J.

    2014-12-01

    Korean Ministry of Trade, Industry and Energy (MOTIE) announced the national plan for Korea's future electric power supply (2013 - 2027) in 2013. According to the plan, the national demand for electricity will be increased by 60% compared to that of 2010 and primary energy sources for electric generation will still lean on the fossil fuels such as petroleum, LNG, and coal, which would be a potential threat to air quality of Korea. This study focused on two subjects: (1) How the spatial distribution of the primary air pollutant's emissions (i.e., NOx, SOx, CO, PM) will be changed and (2) How the primary emission changes will influence on the national ambient air quality including ozone in 2027. We used GEOS-Chem model simulation with modification of Korean emissions inventory (Clean Air Policy Support System (CAPSS)) to simulate the current and future air quality in Korea. The national total emissions of CO, NOx, SOx, PM in year 2027 will be increased by 3%, 8%, 13%, 2%, respectively compared to 2010 and there are additional concern that the future location of the power plants will be closer to the Seoul Metropolitan Area (SMA), where there are approximately 20 million population vulnerable to the potentially worsened air quality. While there are slight increase of concentration of CO, NOx, SOx, and PM in 2027, the O3 concentration is expected to be similar to the level of 2010. Those results may imply the characteristics of air pollution in East Asia such as potentially severe O3 titration and poorer O3/CO or O3/NOx ratio. Furthermore, we will discuss on the impact of transboundary pollution transport from China in the future, which is one of the large factors to control the air quality of Korea.

  12. Electric potential profile of a spherical soft particle with a charged core

    NASA Astrophysics Data System (ADS)

    Phan, Anh D.; Tracy, Dustin A.; Nguyen, T. L. Hoai; Viet, N. A.; Phan, The-Long; Nguyen, Thanh H.

    2013-12-01

    The electrostatic potential profile of a spherical soft particle is derived by solving the Poisson-Boltzmann equations on a spherical system both numerically and analytically. The soft particle is assumed to consist of an ion-permeable charged outer layer and a non-permeable charged core with constant charged density. The contribution of the core to the potential profile is calculated for different charges and dielectric constants. Our results show that the charged core heavily influences the local potential within the soft particle. By contrast, the potential distribution outside the particle in the salt solution is found to be weakly dependent on the core features. These findings are consistent with previous experiments showing the minor impact of the core of the MS2 virus on its overall electrical properties. Our studies also indicate that while a change in temperature from 290 K to 310 K only slightly varies the potential, the ionic strength in the range of 1-600 mM has a significant effect on the potential profile. Our studies would provide good understanding for experimental research in the field of biophysics and nanomedicine.

  13. Energy Savings Measure Packages: Existing Homes

    SciTech Connect

    Casey, S.; Booten, C.

    2011-11-01

    This document presents the most cost effective Energy Savings Measure Packages (ESMP) for existing mixed-fuel and all electric homes to achieve 15% and 30% savings for each BetterBuildings grantee location across the US. These packages are optimized for minimum cost to homeowners for given source energy savings given the local climate and prevalent building characteristics (i.e. foundation types). Maximum cost savings are typically found between 30% and 50% energy savings over the reference home. The dollar value of the maximum annual savings varies significantly by location but typically amounts to $300 - $700/year.

  14. Observation of Anomalous Potential Electric Energy in Distilled Water Under Solar Heating

    NASA Astrophysics Data System (ADS)

    Smarandache, Florentin; Christianto, V.

    2011-04-01

    In this paper, we describe a very simple experiment with distilled water which could exhibit anomalous potential electrical energy with very minimum preparation energy. While this observed excess energy here is less impressive than J-P. Beberian's and M. Porringa's, and the material used is also far less exotic than common LENR-CANR experiments, from the viewpoint of minimum preparation requirement --and therefore less barrier for rapid implementation--, it seems that further experiments could be recommended in order to verify and also to explore various implications of this new proposition.

  15. Experimental investigation into the transmembrane electrical potential of the forward osmosis membrane process in electrolyte solutions.

    PubMed

    Bian, Lixia; Fang, Yanyan; Wang, Xiaolin

    2014-01-01

    The transmembrane electrical potential (TMEP) in a forward osmosis membrane process with a single electrolyte solution as the draw and feed solutions was investigated by experiments. The effects of membrane orientation, the electrolyte species (KCl, NaCl, MgCl2, and CaCl2), concentration and concentration ratio of solutions at both sides of membrane on water flux and TMEP were investigated. The results showed that the TMEPs at different membrane orientation cannot completely coincide, which confirmed the effect of membrane asymmetry. The ion diffusion coefficients significantly affected the TMEP across the membrane, with different patterns for different electrolytes and concentrations. PMID:24957177

  16. Experimental Investigation into the Transmembrane Electrical Potential of the Forward Osmosis Membrane Process in Electrolyte Solutions

    PubMed Central

    Bian, Lixia; Fang, Yanyan; Wang, Xiaolin

    2014-01-01

    The transmembrane electrical potential (TMEP) in a forward osmosis membrane process with a single electrolyte solution as the draw and feed solutions was investigated by experiments. The effects of membrane orientation, the electrolyte species (KCl, NaCl, MgCl2, and CaCl2), concentration and concentration ratio of solutions at both sides of membrane on water flux and TMEP were investigated. The results showed that the TMEPs at different membrane orientation cannot completely coincide, which confirmed the effect of membrane asymmetry. The ion diffusion coefficients significantly affected the TMEP across the membrane, with different patterns for different electrolytes and concentrations. PMID:24957177

  17. A study of fatigue crack closure using electric potential and compliance techniques

    NASA Technical Reports Server (NTRS)

    Clarke, C. K.; Cassatt, G. C.

    1976-01-01

    Compared are closure data produced on the same specimen by the crack tip compliance gage and electric potential techniques. Experiments on 7075-T651 aluminum center cracked panels produced equivalent results on closure using the two techniques. The results also indicated that closure is a function of stress ratio, specimen thickness and maximum applied stress intensity. Maximum stress intensity had a strong effect on closure in the range of applied stresses used. This dependence of closure on specimen thickness and maximum stress intensity accounts for many of the discrepencies in closure behavior reported in the literature.

  18. Material gauge factor of directional electric potential drop sensors for creep monitoring

    SciTech Connect

    Madhi, E.; Nagy, P. B.

    2011-06-23

    Directional electric potential drop measurements can be exploited for in-situ monitoring of creep in metals. The sensor monitors the variation in the ratio of the resistances measured simultaneously in the axial and lateral directions using a square-electrode configuration. This method can efficiently separate the mostly isotropic common part of the resistivity variation caused by reversible temperature variations from the mostly anisotropic differential part caused by direct geometrical (size and shape) and indirect material (resistivity) effects of creep. Similarly to ordinary strain gauges, the relative sensitivity of the sensor is defined as a gauge factor that can be approximated as the sum of geometrical and material parts. Initially, subtle material changes produce weak electric anisotropy via reversible and irreversible piezoresistivity due to elastic and plastic strains, respectively. At high temperature, much stronger irreversible resistivity changes also occur due to preferentially aligned clusters of cavities developing along grain boundaries approximately perpendicular to the applied stress and subsequent cracks forming between these cavities. The ensuing electric anisotropy is detected by the directional sensor. Although the material effects remain smaller than the geometrical ones up to the initiation of preferentially oriented cracks, later the material gauge factor sharply increases and close to rupture can reach a value of more than 10.

  19. Potential Operating Orbits for Fission Electric Propulsion Systems Driven by the SAFE-400

    NASA Technical Reports Server (NTRS)

    Houts, Mike; Kos, Larry; Poston, David; Rodgers, Stephen L. (Technical Monitor)

    2002-01-01

    Safety must be ensured during all phases of space fission system design, development, fabrication, launch, operation, and shutdown. One potential space fission system application is fission electric propulsion (FEP), in which fission energy is converted into electricity and used to power high efficiency (Isp greater than 3000s) electric thrusters. For these types of systems it is important to determine which operational scenarios ensure safety while allowing maximum mission performance and flexibility. Space fission systems are essentially nonradioactive at launch, prior to extended operation at high power. Once high power operation begins, system radiological inventory steadily increases as fission products build up. For a given fission product isotope, the maximum radiological inventory is typically achieved once the system has operated for a length of time equivalent to several half-lives. After that time, the isotope decays at the same rate it is produced, and no further inventory builds in. For an FEP mission beginning in Earth orbit, altitude and orbital lifetime increase as the propulsion system operates. Two simultaneous effects of fission propulsion system operation are thus (1) increasing fission product inventory and (2) increasing orbital lifetime. Phrased differently, as fission products build up, more time is required for the fission products to naturally convert back into non-radioactive isotopes. Simultaneously, as fission products build up, orbital lifetime increases, providing more time for the fission products to naturally convert back into non-radioactive isotopes. Operational constraints required to ensure safety can thus be quantified.

  20. Hyperpolarization of the membrane potential in cardiomyocyte tissue slices by the synchronization modulation electric field.

    PubMed

    Dando, Robin; Fang, Zhihui; Chen, Wei

    2012-02-01

    Our previous studies have shown that a specially designed, so-called synchronization modulation electric field can entrain active transporter Na/K pumps in the cell membrane. This approach was previously developed in a study of single cells using a voltage clamp to monitor the pump currents. We are now expanding our study from isolated single cells to aggregated cells in a 3-dimensional cell matrix, through the use of a tissue slice from the rat heart. The slice is about 150 μm in thickness, meaning the slices contain many cell layers, resulting in a simplified 3-dimensional system. A fluorescent probe was used to identify the membrane potential and the ionic concentration gradients across the cell membrane. In spite of intrinsic cell-to-cell interactions and the difficulty in stimulating cell aggregation in the tissue slice, the oscillating electric field increased the intracellular fluorescent intensity, indicating elevation of the cell ionic concentration and hyperpolarization of the cell membrane. Blockage of these changes by ouabain confirmed that the results are directly related to Na/K pumps. These results along with the backward modulation indicate that the synchronization modulation electric field can influence the Na/K pumps in tissue cells of a 3-dimensional matrix and therefore hyperpolarize the cell membrane.

  1. Electrical impedance spectroscopy as a potential tool for recovering bone porosity

    NASA Astrophysics Data System (ADS)

    Bonifasi-Lista, C.; Cherkaev, E.

    2009-05-01

    This paper deals with the recovery of porosity of bone from measurements of its effective electrical properties. The microstructural information is contained in the spectral measure in the Stieltjes representation of the bone effective complex permittivity or complex conductivity and can be recovered from the measurements over a range of frequencies. The problem of reconstruction of the spectral measure is very ill-posed and requires the use of regularization techniques. We apply the method to the effective electrical properties of cancellous bone numerically calculated using micro-CT images of human vertebrae. The presented method is based on an analytical approach and does not rely on correlation analysis nor on any a priori model of the bone micro-architecture. However the method requires a priori knowledge of the properties of the bone constituents (trabecular tissue and bone marrow). These properties vary from patient to patient. To address this issue, a sensitivity analysis of the technique was performed. Normally distributed random noise was added to the data to simulate uncertainty in the properties of the constituents and possible experimental errors in measurements of the effective properties. The values of porosity calculated from effective complex conductivity are in good agreement with the true values of bone porosity even assuming high level errors in the estimation of the bone components. These results prove the future potential of electrical impedance spectroscopy for in vivo monitoring of level and treatment of osteoporosis.

  2. Impedance and electrically evoked compound action potential (ECAP) drop within 24 hours after cochlear implantation.

    PubMed

    Chen, Joshua Kuang-Chao; Chuang, Ann Yi-Chiun; Sprinzl, Georg Mathias; Tung, Tao-Hsin; Li, Lieber Po-Hung

    2013-01-01

    Previous animal study revealed that post-implantation electrical detection levels significantly declined within days. The impact of cochlear implant (CI) insertion on human auditory pathway in terms of impedance and electrically evoked compound action potential (ECAP) variation within hours after surgery remains unclear, since at this time frequency mapping can only commence weeks after implantation due to factors associated with wound conditions. The study presented our experiences with regards to initial switch-on within 24 hours, and thus the findings about the milieus inside cochlea within the first few hours after cochlear implantation in terms of impedance/ECAP fluctuations. The charts of fifty-four subjects with profound hearing impairment were studied. A minimal invasive approach was used for cochlear implantation, characterized by a small skin incision (≈ 2.5 cm) and soft techniques for cochleostomy. Impedance/ECAP was measured intro-operatively and within 24 hours post-operatively. Initial mapping within 24 hours post-operatively was performed in all patients without major complications. Impedance/ECAP became significantly lower measured within 24 hours post-operatively as compared with intra-operatively (p<0.001). There were no differences between pre-operative and post-operative threshold for air-conduction hearing. A significant drop of impedance/ECAP in one day after cochlear implantation was revealed for the first time in human beings. Mechanisms could be related to the restoration of neuronal sensitivity to the electrical stimulation, and/or the interaction between the matrix enveloping the electrodes and the electrical stimulation of the initial switch-on. Less wound pain/swelling and soft techniques both contributed to the success of immediate initial mapping, which implied a stable micro-environment inside the cochlea despite electrodes insertion. Our research invites further studies to correlate initial impedance/ECAP changes with long

  3. Impedance and Electrically Evoked Compound Action Potential (ECAP) Drop within 24 Hours after Cochlear Implantation

    PubMed Central

    Chen, Joshua Kuang-Chao; Chuang, Ann Yi-Chiun; Sprinzl, Georg Mathias; Tung, Tao-Hsin; Li, Lieber Po-Hung

    2013-01-01

    Previous animal study revealed that post-implantation electrical detection levels significantly declined within days. The impact of cochlear implant (CI) insertion on human auditory pathway in terms of impedance and electrically evoked compound action potential (ECAP) variation within hours after surgery remains unclear, since at this time frequency mapping can only commence weeks after implantation due to factors associated with wound conditions. The study presented our experiences with regards to initial switch-on within 24 hours, and thus the findings about the milieus inside cochlea within the first few hours after cochlear implantation in terms of impedance/ECAP fluctuations. The charts of fifty-four subjects with profound hearing impairment were studied. A minimal invasive approach was used for cochlear implantation, characterized by a small skin incision (≈2.5 cm) and soft techniques for cochleostomy. Impedance/ECAP was measured intro-operatively and within 24 hours post-operatively. Initial mapping within 24 hours post-operatively was performed in all patients without major complications. Impedance/ECAP became significantly lower measured within 24 hours post-operatively as compared with intra-operatively (p<0.001). There were no differences between pre-operative and post-operative threshold for air-conduction hearing. A significant drop of impedance/ECAP in one day after cochlear implantation was revealed for the first time in human beings. Mechanisms could be related to the restoration of neuronal sensitivity to the electrical stimulation, and/or the interaction between the matrix enveloping the electrodes and the electrical stimulation of the initial switch-on. Less wound pain/swelling and soft techniques both contributed to the success of immediate initial mapping, which implied a stable micro-environment inside the cochlea despite electrodes insertion. Our research invites further studies to correlate initial impedance/ECAP changes with long

  4. Assessment of the potential of halophytes as energy crops for the electric utility industry. Final report

    SciTech Connect

    Goodin, J.R.

    1984-09-01

    This technical report assesses and estimates the potential of selected halophytes as future renewable energy resources, especially by US electric utilities, and familiarizes nonspecialists with research and development problems that must be resolved before these energy sources can become dependable supplies of energy. A literature search related to both indigenous and exotic species of halophytes has been done and appropriate terrestrial species have been selected. Selection criteria include: total biomass potential, genetic constraints, establishment and cultivation requirements, regions of suitability, secondary credits, and a number of other factors. Based on these selection criteria, for the arid western states with high levels of salinity in water and/or soils, there is little potential for energy feedstocks derived from grasses and herbaceous forbs. Likewise, coastal marshes, estuaries, and mangrove swamps, although excellent biomass producers, are too limited by region and have too many ecological and environmental problems for consideration. The deep-rooted, perennial woody shrubs indigenous to many saline regions of the west provide the best potential. The number of species in this group is limited, and Atriplex canescens, Sarcobatus vermiculatus, and Chrysothamnus nauseosus are the three species with the greatest biological potential. These shrubs would receive minimal energy inputs in cultivation, would not compete with agricultural land, and would restore productivity to severely disturbed sites. One might logically expect to achieve biomass feedstock yields of three to five tons/acre/yr on a long-term sustainable basis. The possibility also exists that exotic species might be introduced. 67 references, 1 figure, 5 tables.

  5. Nociception-related somatosensory evoked potentials in awake dogs recorded after intra epidermal electrical stimulation.

    PubMed

    van Oostrom, Hugo; Stienen, Peter J; Doornenbal, Arie; Hellebrekers, Ludo J

    2009-02-01

    At present, the specific neurophysiologic methodology of recording pain-related evoked potentials is considered a most promising approach to objectively quantify pain in man. This study was designed to characterise and evaluate the use of somatosensory evoked potentials to study nociception in a canine model. To this aim, somatosensory evoked potentials were evoked by intra-epidermal electrical stimulation and recorded from the scalp in 8 beagle dogs. Characteristics determined were: (1) the conduction velocities of the peripheral nerve fibres involved, (2) the stimulus intensity response characteristics and (3) the evaluation of possible disturbance of the signals by muscular activity from the hind paw withdrawal reflex (EMG artefact). The results showed (1) the conduction velocities to be in the A-delta fibre range (i.e. fibres involved in nociception), (2) an increase in amplitude and a decrease in latency of the evoked potential following increasing stimulus intensities and (3) the absence of EMG artefact in the signals. These data indicate that the evoked potentials recorded, are related to nociception and thus are suited to quantitatively characterise the perception of noxious stimuli making this model useful for pain- and analgesia-related research.

  6. Low-potential respirators support electricity production in microbial fuel cells.

    PubMed

    Grüning, André; Beecroft, Nelli J; Avignone-Rossa, Claudio

    2015-07-01

    In this paper, we analyse how electric power production in microbial fuel cells (MFCs) depends on the composition of the anodic biofilm in terms of metabolic capabilities of identified sets of species. MFCs are a promising technology for organic waste treatment and sustainable bioelectricity production. Inoculated with natural communities, they present a complex microbial ecosystem with syntrophic interactions between microbes with different metabolic capabilities. Our results demonstrate that low-potential anaerobic respirators--that is those that are able to use terminal electron acceptors with a low redox potential--are important for good power production. Our results also confirm that community metabolism in MFCs with natural inoculum and fermentable feedstock is a two-stage system with fermentation followed by anode respiration.

  7. Reticular activating system of a central pattern generator: premovement electrical potentials.

    PubMed

    Tapia, Jesus A; Trejo, Argelia; Linares, Pablo; Alva, J Manuel; Kristeva, Rumyana; Manjarrez, Elias

    2013-10-01

    For the first time, here we characterize a bulbar reticular activating system (RAS) of neurons in decerebrate, deafferented and decerebellated cats producing a premovement electrical potential that we named obex slow potential (OSP). The OSP occurs about 0.8 ± 0.4 sec prior to the onset of a fictive-scratching-episode. Here, we describe two classes of bulbar neurons, off-on, which are silent but exhibit a 80 ± 56 Hz firing discharge at the beginning of (and during) the OSP, and on-off interneurons, with a 27 ± 14 Hz firing activity that stops at the beginning of (and during) the OSP. We suggest that these OSP-associated neurons belong to a descending RAS, which contributes to the activation of the spinal central pattern generators.

  8. Multiscale Simulation of Ionic Flux through a Nanopore under Applied Electric Potential

    NASA Astrophysics Data System (ADS)

    Debusschere, Bert; Adalsteinsson, Helgi; Simmons, Blake; Long, Kevin; Najm, Habib

    2006-11-01

    This talk discusses the development of an atomic/continuum multiscale model for the simulation of electrophoretically driven ionic fluxes through a nanopore of an electrodesalination membrane. The ion transport in this single pore model is simulated using Brownian Dynamics computations, with parameter fields that are obtained from targeted Molecular Dynamics simulations. The Brownian Dynamics simulations couple with a fine-grained Poisson-Nernst-Planck continuum model in the pore vicinity. The model is calibrated against patch clamp measurements of current through track-etched nanoporous membranes under an applied electric potential. Simulations are performed to investigate the effects of pore size, membrane wall charge and applied potential on the pore throughput and selectivity.

  9. Light-dependent cation gradients and electrical potential in Halobacterium halobium cell envelope vesicles

    NASA Technical Reports Server (NTRS)

    Lanyi, J. K.; Macdonald, R. E.

    1977-01-01

    Vesicles can be prepared from Halobacterium halobium cell envelopes, which contain properly oriented bacteriorhodopsin and which extrude H(+) during illumination. The pH difference that is generated across the membranes is accompanied by an electrical potential of 90 to 100 mV (interior negative) and the movements of other cations. Among these is the efflux of Na(+), which proceeds against its electrochemical potential. The relationship between the size and direction of the light-induced pH gradient and the rate of depletion of Na(+) from the vesicles, as well as other evidence, suggest that the active Na(+) extrusion is facilitated by a membrane component that exchanges H(+) for Na(+) with a stoichiometry greater than 1. The gradients of H(+) and Na(+) are thus coupled to one another. The Na(+) gradient (efflux much larger than influx), which arises during illumination, plays a major role in energizing the active transport of amino acids.

  10. Reticular activating system of a central pattern generator: premovement electrical potentials

    PubMed Central

    Tapia, Jesus A; Trejo, Argelia; Linares, Pablo; Alva, J Manuel; Kristeva, Rumyana; Manjarrez, Elias

    2013-01-01

    For the first time, here we characterize a bulbar reticular activating system (RAS) of neurons in decerebrate, deafferented and decerebellated cats producing a premovement electrical potential that we named obex slow potential (OSP). The OSP occurs about 0.8 ± 0.4 sec prior to the onset of a fictive-scratching-episode. Here, we describe two classes of bulbar neurons, off-on, which are silent but exhibit a 80 ± 56 Hz firing discharge at the beginning of (and during) the OSP, and on-off interneurons, with a 27 ± 14 Hz firing activity that stops at the beginning of (and during) the OSP. We suggest that these OSP-associated neurons belong to a descending RAS, which contributes to the activation of the spinal central pattern generators. PMID:24303193

  11. Self-potential and electrical resistivity studies of the Cove Fort-Sulphurdale Geothermal System, Utah

    SciTech Connect

    Ross, H.P.; Blackett, R.E.; Sperry, T.L.

    1997-12-31

    A detailed self-potential (SP) survey was completed at the Cove Fort-Sulphurdale geothermal area during 1995 and 1996. The survey documents a low-amplitude dipolar anomaly within the producing steam field and sharp, negative anomalies which align with mapped structures in the sulfur pit to the south. Three broader SP anomalies, also of relatively low amplitude, were mapped 1 to 2 km west and northwest of the known steam field. One anomaly coincides with the northwestern limit of a very low resistivity (4 ohm-m) area which extends southeast to the steam field, and is open to the west where the other two SP anomalies occur. Electrical resistivity data were modeled to obtain the intrinsic resistivity distribution at various depths, and these are correlated with SP data and structures interpreted from aeromagnetic and gravity data, and geologic mapping. Three potential drilling targets have been identified which could provide new information about the main hot water reservoir.

  12. SunShot Vision Study: A Comprehensive Analysis of the Potential for U.S. Solar Electricity Generation (Fact Sheet)

    SciTech Connect

    Not Available

    2012-06-01

    The SunShot Vision Study provides the most comprehensive assessment to date of the potential for solar technologies to meet a significant share of electricity demand in the United States during the next several decades.

  13. Geometrical gauge factor of directional electric potential drop sensors for creep monitoring

    SciTech Connect

    Madhi, E.; Nagy, P. B.

    2011-06-23

    Directional electric potential drop measurements can be exploited for in-situ monitoring of creep in metals. The sensor monitors the variation in the ratio of the resistances measured simultaneously in the axial and lateral directions using a square-electrode configuration. This technique can efficiently separate the mostly isotropic common part of the resistivity variation caused by reversible temperature variations from the mostly anisotropic differential part caused by direct geometrical and indirect material effects of creep. Initially, this ratio is roughly proportional to the axial creep strain, while at later stages, the resistance ratio increases even faster with creep strain because of the formation of directional discontinuities such as preferentially oriented grain boundary cavities and multiple-site cracks in the material. Similarly to ordinary strain gauges, the relative sensitivity of the sensor is defined as a gauge factor that can be approximated as a sum of geometrical and material parts. This work investigated the geometrical gauge factor by analytical and experimental means. We found that under uniaxial stress square-electrode sensors exhibit geometrical gauge factors of about 4 and 5 in the elastic and plastic regimes, respectively, i.e., more than twice those of conventional strain gauges. Experimental results obtained on 304 stainless steel using a square-electrode electric potential drop creep sensor agree well with our theoretical predictions.

  14. The market potential for SMES in electric utility applications. Final report

    SciTech Connect

    Not Available

    1994-06-01

    Superconducting magnetic energy storage (SMES) is an emerging technology with features that are potentially attractive in electric utility applications. This study evaluates the potential for SMES technology in the generation, transmission, distribution, and use of electric energy; the time frame of the assessment is through the year 2030. Comparisons are made with other technology options, including both commercially available and advanced systems such as various peaking generation technologies, transmission stability improvement technologies, and power quality enhancement devices. The methodology used for this study focused on the needs of the market place, the capabilities of S and the characteristics of the competing technologies. There is widespread interest within utilities for the development of SMES technology, but there is no general consensus regarding the most attractive size. Considerable uncertainty exists regarding the eventual costs and benefits of commercial SMES systems, but general trends have been developed based on current industry knowledge. Results of this analysis indicate that as storage capacity increases, cost increases at a rate faster than benefits. Transmission system applications requiring dynamic storage appear to have the most attractive economics. Customer service applications may be economic in the near term, but improved ride-through capability of end-use equipment may limit the size of this market over time. Other applications requiring greater storage capacity appear to be only marginally economic at best.

  15. Geometrical Gauge Factor of Directional Electric Potential Drop Sensors for Creep Monitoring

    NASA Astrophysics Data System (ADS)

    Madhi, E.; Nagy, P. B.

    2011-06-01

    Directional electric potential drop measurements can be exploited for in-situ monitoring of creep in metals. The sensor monitors the variation in the ratio of the resistances measured simultaneously in the axial and lateral directions using a square-electrode configuration. This technique can efficiently separate the mostly isotropic common part of the resistivity variation caused by reversible temperature variations from the mostly anisotropic differential part caused by direct geometrical and indirect material effects of creep. Initially, this ratio is roughly proportional to the axial creep strain, while at later stages, the resistance ratio increases even faster with creep strain because of the formation of directional discontinuities such as preferentially oriented grain boundary cavities and multiple-site cracks in the material. Similarly to ordinary strain gauges, the relative sensitivity of the sensor is defined as a gauge factor that can be approximated as a sum of geometrical and material parts. This work investigated the geometrical gauge factor by analytical and experimental means. We found that under uniaxial stress square-electrode sensors exhibit geometrical gauge factors of about 4 and 5 in the elastic and plastic regimes, respectively, i.e., more than twice those of conventional strain gauges. Experimental results obtained on 304 stainless steel using a square-electrode electric potential drop creep sensor agree well with our theoretical predictions.

  16. Electric potential patterns in the northern and southern polar regions parameterized by the interplanetary magnetic field

    SciTech Connect

    Papitashvili, V.O. |; Belov, B.A.; Faermark, D.S.; Feldstein, Ya.I.; Golyshev, S.A.; Gromova, L.I.; Levitin, A.E.

    1994-07-01

    Electric potential patterns have been obtained from the IZMIRAN electrodynamic model (IZMEM) for the northern and southern polar regions during summer, winter, and equinox. The model is derived from a large quantity of high-latitude ground-based geomagnetic data (above {+-} 57{degrees} corrected geomagnetic latitude) at all magnetic local time hours. A linear regression analysis technique has been used to obtain the quantitative response of each magnetic observatory to changes of interplanetary magnetic field (IMF) components. Since no ionospheric conductivity model exists specifically for the southern polar region, the statistical model of Wallis and Budzinski has been applied in both hemispheres. A cross-polar `background` potential of {approximately} 35 kV, derived by Reiff et al., is used to calibrate IZMEM`s potential patterns. The model`s response to changes in the IMF B{sub y} and B{sub z} components are analyzed to obtain a set of {open_quotes}elementary{close_quotes} convection patterns in both polar regions for each season of the year. Asymmetry in the potential pattern geometry in both hemispheres can be attributed either to the influence of the {open_quotes}northern{close_quotes} ionospheric conductivity model which was applied to the southern polar region, or to some natural phenomena. Average values of the modeled potential drop caused by each nanotesla of the IMF are the following: {approximately} 14 kV for southward B{sub z}; {approximately} {minus}4 kV for northward B{sub z}; and {approximately} {+-} 4.5 kV for B{sub y} components. The latter is not applicable to the {open_quotes}dawn-dusk{close_quotes} potential drop; it may be applied across the cusp region only. It is concluded that IZMEM provides realistic convection patterns parameterized by the IMF component directions and magnitudes and may be used to provide routine estimates of convection patterns and electric potentials if IMF data are available. 43 refs., 7 figs., 1 tab.

  17. Therapeutic management of uncomplicated gastroesophageal reflux disease in france in 2005: Potential cost savings of omeprazole substitution

    PubMed Central

    Mouly, Stéphane; Charlemagne, Agnès; Lejeunne, Philippe; Fagnani, Francis

    2009-01-01

    other compounds (lansoprazole, pantoprazole, rabeprazole, and esomeprazole) were prescribed at half dose in 64.3% of cases. The extrapolated annual cost of PPIs reimbursed for this indication was €465.02 million at a mean reimbursement level of 72.7%. Brand-name omeprazole still accounted for ≈11% of the total cost reimbursed. Complete replacement of brand-name omeprazole with its generic counterpart would have reduced costs by €18.35 million (a decrease of 4.3% in the total reimbursed expenditure). The switch from generic full-dose omeprazole to a half dose of other PPIs would have allowed further savings ranging from €2.59 million (with lansoprazole) to €13.19 million (with pantoprazole). Conclusion: In accordance with recent recommendations for the treatment of uncomplicated GERD and based on the 2006 PPI pricing, switching from branded full-dose omeprazole to generic omeprazole or to the use of half doses of other PPIs may allow cost savings in France. PMID:24683238

  18. Electric potential dynamics in OH and ECRH plasmas in the T-10 tokamak

    NASA Astrophysics Data System (ADS)

    Melnikov, A. V.; Eliseev, L. G.; Perfilov, S. V.; Andreev, V. F.; Grashin, S. A.; Dyabilin, K. S.; Chudnovskiy, A. N.; Isaev, M. Yu.; Lysenko, S. E.; Mavrin, V. A.; Mikhailov, M. I.; Ryzhakov, D. V.; Shurygin, R. V.; Zenin, V. N.; the T-10 Team

    2013-09-01

    New experimental observations of the plasma potential using the heavy ion beam probe diagnostic are presented together with a theoretical description of the formation of the electric field Er in the T-10 circular tokamak (B0 = 1.5-2.5 T, R = 1.5 m, a = 0.3 m). Ohmically heated (OH) deuterium plasmas with main plasma parameters \\bar{{n}}_{e} =(0.6{--}4.7)\\times 10^{19}\\,m^{-3} , Te(0) < 1.3 keV, Ti(0) < 0.6 keV are characterized by a negative potential φ(ρ) with maximum negative values of φ(6 cm) = -1400 V with respect to the wall. The potential profile monotonically increases towards the plasma edge. A density rise due to gas puff is accompanied by a plasma potential that becomes increasingly negative. When the density approaches values in the range \\bar{{n}}_{e} =(2.5{--}3.5)\\times 10^{19}\\,m^{-3} , the value of the plasma potential saturates, while the energy confinement time still increases up to a saturation value that is obtained at a slightly higher density. With auxiliary heating by electron cyclotron resonance heating (ECRH) up to 1.2 MW, Te(0) increases (up to 3 keV) and the absolute value of the plasma potential decreases. In some cases the plasma potential changes its sign and becomes positive at the edge. The radial profile of Er and its dependence on ne and Ti are qualitatively explained by a neoclassical model in the core, and a turbulent dynamic model (Braginskij magnetohydrodynamic equations) in the edge.

  19. Direct observation of DNA motions into solid state nanopore under applied electrical potentials on conductive surface

    NASA Astrophysics Data System (ADS)

    Hayashi, Yoshitaka; Ando, Genki; Idutsu, Ichiro; Mitsui, Toshiyuki

    2011-03-01

    Solid state nanopore is one of emerging methods for rapid single DNA molecule detection because the translocation of the DNA though nanopore produces ionic current changes. One of issues in this method is clogging long DNA molecules. Once DNA molecules clogged, the molecules are rarely removed by varying or switching the polarity of applied bias voltages across the nanopore. We develop a modified nanopore by 50nm Au coating on top of the nanopore surface to be able to remove the clogged DNA molecules during the DNA translocation experiment. Fluorescence microscopy was implemented for observation of stained DNA molecules. The nanopores with diameters near 100 nm can be used initially. DNA translocation rates changes dramatically by tuning the applied electrical potentials on surface higher or lower than the potentials across the nanopore. Furthermore, the Au potentials modifies IV characteristic of the ionic current across the nanopore which is similar to the gate voltages controlling the SD current in FET. We will discuss the influence of surface potential on DNA motion and translocation and clogged DNA molecules. Finally, we will present the recent results of DNA translocation into the SiN-Au-SiO2 nanopore and discuss the effect of applied voltages on Au.

  20. Coupling of surface energy with electric potential makes superhydrophobic surfaces corrosion-resistant.

    PubMed

    Ramachandran, Rahul; Nosonovsky, Michael

    2015-10-14

    We study the correlation of wetting properties and corrosion rates on hydrophobized cast iron. Samples of different surface roughnesses (abraded by sandpaper) are studied without coating and with two types of hydrophobic coatings (stearic acid and a liquid repelling spray). The contact angles and contact angle hysteresis are measured using a goniometer while corrosion rates are measured by a potentiodynamic polarization test. The data show a decrease in corrosion current density and an increase in corrosion potential after superhydrophobization. A similar trend is also found in the recent literature data. We conclude that a decrease in the corrosion rate can be attributed to the changing open circuit potential of a coated surface and increased surface area making the non-homogeneous (Cassie-Baxter) state possible. We interpret these results in light of the idea that the inherent surface energy is coupled with the electric potential in accordance with the Lippmann law of electrowetting and Le Châtelier's principle and, therefore, hydrophobization leads to a decrease in the corrosion potential. This approach can be used for novel anti-corrosive coatings. PMID:26344151

  1. Electrical coupling in ensembles of nonexcitable cells: modeling the spatial map of single cell potentials.

    PubMed

    Cervera, Javier; Manzanares, Jose Antonio; Mafe, Salvador

    2015-02-19

    We analyze the coupling of model nonexcitable (non-neural) cells assuming that the cell membrane potential is the basic individual property. We obtain this potential on the basis of the inward and outward rectifying voltage-gated channels characteristic of cell membranes. We concentrate on the electrical coupling of a cell ensemble rather than on the biochemical and mechanical characteristics of the individual cells, obtain the map of single cell potentials using simple assumptions, and suggest procedures to collectively modify this spatial map. The response of the cell ensemble to an external perturbation and the consequences of cell isolation, heterogeneity, and ensemble size are also analyzed. The results suggest that simple coupling mechanisms can be significant for the biophysical chemistry of model biomolecular ensembles. In particular, the spatiotemporal map of single cell potentials should be relevant for the uptake and distribution of charged nanoparticles over model cell ensembles and the collective properties of droplet networks incorporating protein ion channels inserted in lipid bilayers. PMID:25622192

  2. Visualizing Nanoscale Distribution of Corrosion Cells by Open-Loop Electric Potential Microscopy.

    PubMed

    Honbo, Kyoko; Ogata, Shoichiro; Kitagawa, Takuya; Okamoto, Takahiro; Kobayashi, Naritaka; Sugimoto, Itto; Shima, Shohei; Fukunaga, Akira; Takatoh, Chikako; Fukuma, Takeshi

    2016-02-23

    Corrosion is a traditional problem but still one of the most serious problems in industry. To reduce the huge economic loss caused by corrosion, tremendous effort has been made to understand, predict and prevent it. Corrosion phenomena are generally explained by the formation of corrosion cells at a metal-electrolyte interface. However, experimental verification of their nanoscale distribution has been a major challenge owing to the lack of a method able to visualize the local potential distribution in an electrolytic solution. In this study, we have investigated the nanoscale corrosion behavior of Cu fine wires and a duplex stainless steel by in situ imaging of local corrosion cells by open-loop electric potential microscopy (OL-EPM). For both materials, potential images obtained by OL-EPM show nanoscale contrasts, where areas of higher and lower potential correspond to anodic areas (i.e., corrosion sites) and cathodic areas, respectively. This imaging capability allows us to investigate the real-time transition of local corrosion sites even when surface structures show little change. This is particularly useful for investigating reactions under surface oxide layers or highly corrosion-resistant materials as demonstrated here. The proposed technique should be applicable to the study of other redox reactions on a battery electrode or a catalytic material. The results presented here open up such future applications of OL-EPM in nanoscale electrochemistry. PMID:26811989

  3. Electrical coupling in ensembles of nonexcitable cells: modeling the spatial map of single cell potentials.

    PubMed

    Cervera, Javier; Manzanares, Jose Antonio; Mafe, Salvador

    2015-02-19

    We analyze the coupling of model nonexcitable (non-neural) cells assuming that the cell membrane potential is the basic individual property. We obtain this potential on the basis of the inward and outward rectifying voltage-gated channels characteristic of cell membranes. We concentrate on the electrical coupling of a cell ensemble rather than on the biochemical and mechanical characteristics of the individual cells, obtain the map of single cell potentials using simple assumptions, and suggest procedures to collectively modify this spatial map. The response of the cell ensemble to an external perturbation and the consequences of cell isolation, heterogeneity, and ensemble size are also analyzed. The results suggest that simple coupling mechanisms can be significant for the biophysical chemistry of model biomolecular ensembles. In particular, the spatiotemporal map of single cell potentials should be relevant for the uptake and distribution of charged nanoparticles over model cell ensembles and the collective properties of droplet networks incorporating protein ion channels inserted in lipid bilayers.

  4. Dynamic polarizability and electric multipolar transitions in two electron atoms under exponential cosine screened coulomb potential

    NASA Astrophysics Data System (ADS)

    Chaudhuri, Supriya K.; Modesto-Costa, Lucas; Mukherjee, Prasanta K.

    2016-05-01

    Detailed investigations on the frequency dependent polarizabilities, transition energies, oscillator strengths, and transition probabilities of two electron systems He, B e2 +, C4 + , and O6 + under electric dipolar (E1) and quadrupolar (E2) excitations have been performed using exponential cosine screened coulomb potential with a view to understand the structural behaviour of such systems due to external confinement produced by plasma environment. Time dependent coupled Hartree-Fock theory within a variational framework has been adopted for studying the first three low lying excited states 1 s2:1Se→1 s n p :1Po (n = 2, 3, 4) and 1 s n d :1De (n = 3, 4, 5) under such excitations. Quantitatively, the effect of confinement produced by the external plasma has been taken care of by considering the change in atomic potential through plasma screening, directly related to the coupling strength of the plasma with the atomic charge cloud. With increased plasma screening, a gradual destabilisation of the energy levels with subsequent reduction of the ionization potential and number of excited states has been observed. Behavioral pattern of the frequency dependent polarizabilities, excitation energies, oscillator strengths, and transition probabilities under systematic increase of the screening has been investigated. Results have been compared thoroughly with those available for free systems and under confinement by exponential cosine screened and screened Coulomb potential.

  5. Lunar Surface Electric Potential Changes Associated with Traversals through the Earth's Foreshock

    NASA Technical Reports Server (NTRS)

    Collier, Michael R.; Hills, H. Kent; Stubbs, Timothy J.; Halekas, Jasper S.; Delory, Gregory T.; Espley, Jared; Farrell, William M.; Freeman, John W.; Vondrak, Richard

    2011-01-01

    We report an analysis of one year of Suprathermal Ion Detector Experiment (SIDE) Total Ion Detector (TID) resonance events observed between January 1972 and January 1973. The study includes only those events during which upstream solar wind conditions were readily available. The analysis shows that these events are associated with lunar traversals through the dawn flank of the terrestrial magnetospheric bow shock. We propose that the events result from an increase in lunar surface electric potential effected by secondary electron emission due to primary electrons in the Earth's foreshock region (although primary ions may play a role as well). This work establishes (1) the lunar surface potential changes as the Moon moves through the terrestrial bow shock, (2) the lunar surface achieves potentials in the upstream foreshock region that differ from those in the downstream magnetosheath region, (3) these differences can be explained by the presence of energetic electron beams in the upstream foreshock region and (4) if this explanation is correct, the location of the Moon with respect to the terrestrial bow shock influences lunar surface potential.

  6. Sharing the savings to promote energy efficiency

    SciTech Connect

    Eto, J.; Destribats, A.; Schultz, D.

    1992-04-01

    Shared-savings incentives offer a new way for regulated utilities to improve earnings by encouraging customer energy efficiency. Benefits of cost-effective energy efficiency measures can be shared explicitly among customers participating in an utility demand-side management (DSM) program, all utility ratepayers, and the utility itself. For participating customers, electricity bills are lowered directly; for ratepayers, the costs of providing electric services are reduced; and for utility shareholders, they are allowed to retain a fraction of the net benefits as additional earnings. In this study, we define the basic elements of shared-savings arrangements for utility demandside resources. Next, we compare and contrast specific details of the arrangements approved for three different utilities: Pacific Gas and Electric Company (PG&E), San Diego Gas and Electric Company (SDG&E), and two operating subsidiaries of the New England Electric System (NEES). Our analysis suggests that the percentage share of net benefits on which utilities are allowed to earn is a relatively poor indicator of the incentive mechanism`s overall affect on utility earnings. Earnings opportunities and potential are also significantly influenced by particular incentive features. These include the definition and measurement of load reductions, program costs, and program benefits; program cost recovery and the timing of incentive recovery; performance thresholds; program spending and earnings caps; program eligibility criteria; treatment of lost revenues; and for NEES, a complementary, non-shared-savings incentive. We conclude that the ``collaborative`` processes used to develop incentives for each utility proved extremely useful in allowing parties to negotiate trade-offs inherent between various program design features.

  7. Sharing the savings to promote energy efficiency

    SciTech Connect

    Eto, J.; Destribats, A.; Schultz, D.

    1992-04-01

    Shared-savings incentives offer a new way for regulated utilities to improve earnings by encouraging customer energy efficiency. Benefits of cost-effective energy efficiency measures can be shared explicitly among customers participating in an utility demand-side management (DSM) program, all utility ratepayers, and the utility itself. For participating customers, electricity bills are lowered directly; for ratepayers, the costs of providing electric services are reduced; and for utility shareholders, they are allowed to retain a fraction of the net benefits as additional earnings. In this study, we define the basic elements of shared-savings arrangements for utility demandside resources. Next, we compare and contrast specific details of the arrangements approved for three different utilities: Pacific Gas and Electric Company (PG E), San Diego Gas and Electric Company (SDG E), and two operating subsidiaries of the New England Electric System (NEES). Our analysis suggests that the percentage share of net benefits on which utilities are allowed to earn is a relatively poor indicator of the incentive mechanism's overall affect on utility earnings. Earnings opportunities and potential are also significantly influenced by particular incentive features. These include the definition and measurement of load reductions, program costs, and program benefits; program cost recovery and the timing of incentive recovery; performance thresholds; program spending and earnings caps; program eligibility criteria; treatment of lost revenues; and for NEES, a complementary, non-shared-savings incentive. We conclude that the collaborative'' processes used to develop incentives for each utility proved extremely useful in allowing parties to negotiate trade-offs inherent between various program design features.

  8. Clean Energy Technologies: A Preliminary Inventory of the Potential for Electricity Generation

    SciTech Connect

    Bailey, Owen; Worrell, Ernst

    2005-08-03

    The nation's power system is facing a diverse and broad set of challenges. These range from restructuring and increased competitiveness in power production to the need for additional production and distribution capacity to meet demand growth, and demands for increased quality and reliability of power and power supply. In addition, there are growing concerns about emissions from fossil fuel powered generation units and generators are seeking methods to reduce the CO{sub 2} emission intensity of power generation. Although these challenges may create uncertainty within the financial and electricity supply markets, they also offer the potential to explore new opportunities to support the accelerated deployment of cleaner and cost-effective technologies to meet such challenges. The federal government and various state governments, for example, support the development of a sustainable electricity infrastructure. As part of this policy, there are a variety of programs to support the development of ''cleaner'' technologies such as combined heat and power (CHP, or cogeneration) and renewable energy technologies. Energy from renewable energy sources, such as solar, wind, hydro, and biomass, are considered carbon-neutral energy technologies. The production of renewable energy creates no incremental increase in fossil fuel consumption and CO{sub 2} emissions. Electricity and thermal energy production from all renewable resources, except biomass, produces no incremental increase in air pollutants such as nitrogen oxides, sulfur oxides, particulate matter, and carbon monoxide. There are many more opportunities for the development of cleaner electricity and thermal energy technologies called ''recycled'' energy. A process using fossil fuels to produce an energy service may have residual energy waste streams that may be recycled into useful energy services. Recycled energy methods would capture energy from sources that would otherwise be unused and convert it to electricity or

  9. Spectral distribution of local field potential responses to electrical stimulation of the retina

    NASA Astrophysics Data System (ADS)

    Wong, Yan T.; Halupka, Kerry; Kameneva, Tatiana; Cloherty, Shaun L.; Grayden, David B.; Burkitt, Anthony N.; Meffin, Hamish; Shivdasani, Mohit N.

    2016-06-01

    Objective. Different frequency bands of the local field potential (LFP) have been shown to reflect neuronal activity occurring at varying cortical scales. As such, recordings of the LFP may offer a novel way to test the efficacy of neural prostheses and allow improvement of stimulation strategies via neural feedback. Here we use LFP measurements from visual cortex to characterize neural responses to electrical stimulation of the retina. We aim to show that the LFP is a viable signal that contains sufficient information to optimize the performance of sensory neural prostheses. Approach. Clinically relevant electrode arrays were implanted in the suprachoroidal space of one eye in four felines. LFPs were simultaneously recorded in response to stimulation of individual electrodes using penetrating microelectrode arrays from the visual cortex. The frequency response of each electrode was extracted using multi-taper spectral analysis and the uniqueness of the responses was determined via a linear decoder. Main results. We found that cortical LFPs are reliably modulated by electrical stimulation of the retina and that the responses are spatially localized. We further characterized the spectral distribution of responses, with maximum information being contained in the low and high gamma bands. Finally, we found that LFP responses are unique to a large range of stimulus parameters (∼40) with a maximum conveyable information rate of 6.1 bits. Significance. These results show that the LFP can be used to validate responses to electrical stimulation of the retina and we provide the first steps towards using these responses to provide more efficacious stimulation strategies.

  10. Macroscopic electric charge separation during hypervelocity impacts: Potential implications for planetary paleomagnetism

    NASA Technical Reports Server (NTRS)

    Crawford, D. A.; Schultz, P. H.

    1993-01-01

    The production of transient magnetic fields by hypervelocity meteoroid impact has been proposed to possibly explain the presence of paleomagnetic fields in certain lunar samples as well as across broader areas of the lunar surface. In an effort to understand the lunar magnetic record, continued experiments at the NASA Ames Vertical Gun Range allow characterizing magnetic fields produced by the 5 km/s impacts of 0.32-0.64 cm projectiles over a broad range of impact angles and projectile/target compositions. From such studies, another phenomenon has emerged, macroscopic electric charge separation, that may have importance for the magnetic state of solid-body surfaces. This phenomenon was observed during explosive cratering experiments, but the magnetic consequences of macroscopic electric charge separation (as opposed to plasma production) during explosion and impact cratering have not, to our knowledge, been explored before now. It is straightforward to show that magnetic field production due to this process may scale as a weakly increasing function of impactor kinetic energy, although more work is needed to precisely assess the scaling dependence. The original intent of our experiments was to assess the character of purely electrostatic signals for comparison with inferred electrostatic noise signals acquired by shielded magnetic sensors buried within particulate dolomite targets. The results demonstrated that electrostatic noise does affect the magnetic sensors but only at relatively short distances (less than 4 cm) from the impact point (our magnetic studies are generally performed at distances greater than approximately 5.5 cm). However, to assess models for magnetic field generation during impact, measurements are needed of the magnetic field as close to the impact point as possible; hence, work with an improved magnetic sensor design is in progress. In this paper, we focus on electric charge separation during hypervelocity impacts as a potential transient

  11. Modeling energy savings from urban shade trees: an assessment of the CITYgreen energy conservation module.

    PubMed

    Carver, Andrew D; Unger, Daniel R; Parks, Courtney L

    2004-11-01

    CITYgreen software has become a commonly used tool to quantify the benefits of urban shade trees. Despite its frequent use, little research has been conducted to validate results of the CITYgreen energy conservation module. The first objective of this study is to perform a familiar application of CITYgreen software to predict the potential energy savings contribution of existing tree canopies in residential neighborhoods during peak cooling summer months. Unlike previous studies utilizing CITYgreen, this study also seeks to assess the software's performance by comparing model results (i.e., predicted energy savings) with actual savings (i.e., savings derived directly from energy consumption data provided by the electric utility provider). Homeowners in an older neighborhood with established trees were found to use less energy for air-conditioning than homeowners in a recently developed site. Results from the assessment of model performance indicated that CITYgreen more accurately estimated the energy savings in the highly vegetated, older neighborhood.

  12. Incorporating the productivity benefits into the assessment of cost effective energy savings potential using conservation supply curves

    SciTech Connect

    Laitner, John A.; Ruth, Michael; Worrell, Ernst

    2001-07-24

    We review the relationship between energy efficiency improvement measures and productivity in industry. We propose a method to include productivity benefits in the economic assessment of the potential for energy efficiency improvement. The paper explores the implications of how this change in perspective might affect the evaluation of energy-efficient technologies for a study of the iron and steel industry in the U.S. It is found that including productivity benefits explicitly in the modeling parameters would double the cost-effective potential for energy efficiency improvement, compared to an analysis excluding those benefits. We provide suggestions for future research for this important area.

  13. Identifying Hydrologic Flowpaths on Arctic Hillslopes Using Electrical Resistivity and Self Potential

    NASA Astrophysics Data System (ADS)

    Voytek, E.; Rushlow, C. R.; Godsey, S.; Singha, K.

    2015-12-01

    Shallow subsurface flow is a dominant process controlling hillslope runoff generation, soil development, and solute reaction and transport. Despite their importance, the location and geometry of flowpaths are difficult to determine. In arctic environments, shallow subsurface flowpaths are limited to a thin zone of seasonal thaw above continuous permafrost, which is traditionally assumed to mimic to surface topography. Here we use a combined approach of electrical resistivity imaging (ERI) and self-potential measurements (SP) to map shallow subsurface flowpaths in and around water tracks, drainage features common to arctic hillslopes. ERI measurements delineate thawed zones in the subsurface that control flowpaths, while SP is sensitive to groundwater flow. We find that areas of low electrical resistivity in the water tracks are deeper than manual thaw depth estimates and variations from surface topography. This finding suggests that traditional techniques significantly underestimate active layer thaw and the extent of the flowpath network on arctic hillslopes. SP measurements identify complex 3-D flowpaths in the thawed zone. Our results lay the groundwork for investigations into the seasonal dynamics, hydrologic connectivity, and climate sensitivity of spatially distributed flowpath networks on arctic hillslopes.

  14. Potential of electric quadrupole transitions in radium isotopes for single-ion optical frequency standards

    SciTech Connect

    Versolato, O. O.; Wansbeek, L. W.; Jungmann, K.; Timmermans, R. G. E.; Willmann, L.; Wilschut, H. W.

    2011-04-15

    We explore the potential of the electric quadrupole transitions 7s {sup 2}S{sub 1/2}-6d {sup 2}D{sub 3/2}, 6d {sup 2}D{sub 5/2} in radium isotopes as single-ion optical frequency standards. The frequency shifts of the clock transitions due to external fields and the corresponding uncertainties are calculated. Several competitive {sup A}Ra{sup +} candidates, with A= 223-229, are identified. In particular, we show that the transition 7s {sup 2}S{sub 1/2} (F=2,m{sub F}=0)-6d {sup 2}D{sub 3/2} (F=0,m{sub F}=0) at 828 nm in {sup 223}Ra{sup +}, with no linear Zeeman and electric quadrupole shifts, stands out as a relatively simple case, which could be exploited as a compact, robust, and low-cost atomic clock operating at a fractional frequency uncertainty of 10{sup -17}. With more experimental effort, the {sup 223,225,226}Ra{sup +} clocks could be pushed to a projected performance reaching the 10{sup -18} level.

  15. Effects of local electric surface potential on holes charging process in uncapped germanium nanocrystal

    SciTech Connect

    Marchand, Aude; El Hdiy, Abdelillah

    2015-04-21

    The charging kinetics of holes are investigated in an uncapped Ge nanocrystal by the use of the nano-electron beam induced current technique. The charging process is studied under zero volt or under an appropriate electric field. The investigation is repeated many times on the same nanocrystal and on others in the same sample to attest of the reproducibility of the results. At 0 V, the cycles of charging kinetics are superimposed and are in a steady state, but an instantaneous local and negative surface potential, established in the nanocrystal at the beginning of the kinetics, slows down the holes charging process. Under an external field, the energy band bending accentuation affects the holes charging time constants. As a result, the holes charging cycles weakly affect the electrical performance of the thin oxide as is indicated by the value of the measured local resistivity of 6 × 10{sup 10}–10{sup 11} Ω cm, which is relatively lower than that of the thick thermal oxide.

  16. Potential of electric quadrupole transitions in radium isotopes for single-ion optical frequency standards

    NASA Astrophysics Data System (ADS)

    Versolato, O. O.; Wansbeek, L. W.; Jungmann, K.; Timmermans, R. G. E.; Willmann, L.; Wilschut, H. W.

    2011-04-01

    We explore the potential of the electric quadrupole transitions 7s2S1/2-6d2D3/2, 6d2D5/2 in radium isotopes as single-ion optical frequency standards. The frequency shifts of the clock transitions due to external fields and the corresponding uncertainties are calculated. Several competitive ARa+ candidates, with A= 223-229, are identified. In particular, we show that the transition 7s2S1/2(F=2,mF=0)-6d2D3/2(F=0,mF=0) at 828 nm in Ra223+, with no linear Zeeman and electric quadrupole shifts, stands out as a relatively simple case, which could be exploited as a compact, robust, and low-cost atomic clock operating at a fractional frequency uncertainty of 10-17. With more experimental effort, the Ra223,225,226+ clocks could be pushed to a projected performance reaching the 10-18 level.

  17. Real-time imaging of membrane potentials during exposure to nanosecond pulsed electric fields

    NASA Astrophysics Data System (ADS)

    Kolb, Juergen F.; Frey, Wolfgang; White, Jody A.; Price, R. O.; Blackmore, Peter F.; Beebe, Stephen J.; Joshi, Ravindra P.; Schoenbach, Karl H.

    2005-04-01

    The charging of mammalian cell plasma membranes in response to ultrashort pulsed electric fields of 60 ns and field strengths up to 100 kV/cm was investigated. Membranes of Jurkat cells were stained with a potential-sensitive dye, Annine-6 and placed in a microreactor mounted on an inverted fluorescence microscope. Images of changes in the fluorescence intensity during the exposure were recorded with a high-sensitivity CCD-camera. A temporal resolution of 5 ns was achieved by illuminating the cells with a 5 ns laser pulse from a dye-laser. The laser pulse was synchronized with the high voltage pulse to record images at specific times before, during and after exposure to the electric field. When exposing Jurkat cells to a 60 ns, 100 kV/cm pulse, each hemisphere of the plasma membrane (as oriented with respect to the electrodes) responded uniquely to the applied field. From these observations it is possible to draw conclusions on the charging time of the membrane, maximum transmembrane voltages and the onset of poration.

  18. Myoelectric activity along human gastrocnemius medialis: different spatial distributions of postural and electrically elicited surface potentials.

    PubMed

    Hodson-Tole, Emma F; Loram, Ian D; Vieira, Taian M M

    2013-02-01

    It has recently been shown that motor units in human medial gastrocnemius (MG), activated during standing, occupy relatively small territories along the muscle's longitudinal axis. Such organisation provides potential for different motor tasks to produce differing regional patterns of activity. Here, we investigate whether postural control and nerve electrical stimulation produce equal longitudinal activation patterns in MG. Myoelectric activity, at different proximal-distal locations of MG, was recorded using a linear electrode array. To ensure differences in signal amplitude between channels did not result from local, morphological factors two experimental protocols were completed: (i) quiet standing; (ii) electrical stimulation of the tibial nerve. Averaged, rectified values (ARVs) were calculated for each channel in each condition. The distribution of signals along electrode channels was described using linear regression and differences between protocols at each channel determined as the ratio between mean ARV from standing: stimulation protocols. Ratio values changed systematically across electrode channels in seven (of eight) participants, with larger values in distal channels. The distribution of ARV along MG therefore differed between experimental conditions. Compared to fibres of units activated during MG nerve stimulation, units activated during standing may have a tendency to be more highly represented in the distal muscle portion. PMID:22967836

  19. Dynamics of action potential firing in electrically connected striatal fast-spiking interneurons

    PubMed Central

    Russo, Giovanni; Nieus, Thierry R.; Maggi, Silvia; Taverna, Stefano

    2013-01-01

    Fast-spiking interneurons (FSIs) play a central role in organizing the output of striatal neural circuits, yet functional interactions between these cells are still largely unknown. Here we investigated the interplay of action potential (AP) firing between electrically connected pairs of identified FSIs in mouse striatal slices. In addition to a loose coordination of firing activity mediated by membrane potential coupling, gap junctions (GJ) induced a frequency-dependent inhibition of spike discharge in coupled cells. At relatively low firing rates (2–20 Hz), some APs were tightly synchronized whereas others were inhibited. However, burst firing at intermediate frequencies (25–60 Hz) mostly induced spike inhibition, while at frequencies >50–60 Hz FSI pairs tended to synchronize. Spike silencing occurred even in the absence of GABAergic synapses or persisted after a complete block of GABAA receptors. Pharmacological suppression of presynaptic spike afterhyperpolarization (AHP) caused postsynaptic spikelets to become more prone to trigger spikes at near-threshold potentials, leading to a mostly synchronous firing activity. The complex pattern of functional coordination mediated by GJ endows FSIs with peculiar dynamic properties that may be critical in controlling striatal-dependent behavior. PMID:24294191

  20. Electrically evoked potentials in an ovine model for the evaluation of visual prosthesis efficacy.

    PubMed

    Barriga-Rivera, Alejandro; Eiber, Calvin D; Dodds, Christopher W D; Fung, Adrian T; Tatarinoff, Veronica; Lovell, Nigel H; Suaning, Gregg J

    2015-01-01

    Visual prostheses are becoming a reality as a therapy to restore functional vision to the blind. New stimulation strategies and novel electrode designs are contributing to accelerate the development of such devices triggering the interest of scientists, clinicians and the blind community worldwide. In this scenario, there is a need for large animal models that are suitable for preclinical testing of retinal neuroprostheses. This study presents an electrophysiology assessment of an ovine model for single and simultaneous electrode stimulation from the suprachoroidal space, using symmetric biphasic current pulses with a monopolar return configuration. Visually and electrically evoked potentials were recorded using supradural surface electrodes, showing charge thresholds comparable to those in humans. This model represents an alternative to feline or canine models with analogous activation levels and an eye anatomy similar to that of humans.

  1. Finite-geometry models of electric field noise from patch potentials in ion traps

    SciTech Connect

    Low, Guang Hao; Herskind, Peter F.; Chuang, Isaac L.

    2011-11-15

    We model electric field noise from fluctuating patch potentials on conducting surfaces by taking into account the finite geometry of the ion trap electrodes to gain insight into the origin of anomalous heating in ion traps. The scaling of anomalous heating rates with surface distance d is obtained for several generic geometries of relevance to current ion trap designs, ranging from planar to spheroidal electrodes. The influence of patch size is studied both by solving Laplace's equation in terms of the appropriate Green's function as well as through an eigenfunction expansion. Scaling with surface distance is found to be highly dependent on the choice of geometry and the relative scale between the spatial extent of the electrode, the ion-electrode distance, and the patch size. Our model generally supports the d{sup -4} dependence currently found by most experiments and models, but also predicts geometry-driven deviations from this trend.

  2. Learning about saving energy

    SciTech Connect

    1995-02-01

    This fact sheet for use in primary and junior high school classes describes what energy is, how people use energy, and how energy can be conserved. This last section lists ways to save energy in heating and cooling, electric appliances, automobiles, and in manufacturing. A list of activities are suggested and resources for further information, both groups and books, are listed. A glossary is also included.

  3. Development of 3-D Mechanical Models of Electric Circuits and Their Effect on Students' Understanding of Electric Potential Difference

    ERIC Educational Resources Information Center

    Balta, Nuri

    2015-01-01

    Visualizing physical concepts through models is an essential method in many sciences. While students are mostly proficient in handling mathematical aspects of problems, they frequently lack the ability to visualize and interpret abstract physical concepts in a meaningful way. In this paper, initially the electric circuits and related concepts were…

  4. Relationship Between Aerosol Number Size Distribution and Atmospheric Electric Potential Gradient in an Urban Area

    NASA Astrophysics Data System (ADS)

    Wright, Matthew; Matthews, James; Bacak, Asan; Silva, Hugo; Priestley, Michael; Percival, Carl; Shallcross, Dudley

    2016-04-01

    Small ions are created in the atmosphere by ground based radioactive decay and solar and cosmic radiation ionising the air. The ionosphere is maintained at a high potential relative to the Earth due to global thunderstorm activity, a current from the ionosphere transfers charge back to the ground through the weakly ionised atmosphere. A potential gradient (PG) exists between the ionosphere and the ground that can be measured in fair weather using devices such as an electric field mill. PG is inversely-proportional to the conductivity of the air and therefore to the number of ions of a given electrical mobility; a reduction of air ions will cause an increase of PG. Aerosols in the atmosphere act as a sink of air ions with an attachment rate dependent on aerosol size distribution and ion mobility. These relationships have been used to infer high particulate, and hence pollution, levels in historic datasets of atmospheric PG. A measurement campaign was undertaken in Manchester, UK for three weeks in July and August where atmospheric PG was measured with an electric field mill (JCI131, JCI Chilworth) on a second floor balcony, aerosol size distribution measured with a scanning mobility particle sizer (SMPS, TSI3936), aerosol concentration measured with a condensation particle counter (CPC, Grimm 5.403) and local meteorological measurements taken on a rooftop measurement site ~200 m away. Field mill and CPC data were taken at 1 s intervals and SMPS data in 2.5 minute cycles. Data were excluded for one hour either side of rainfall as rainclouds and droplets can carry significant charge which would affect PG. A quantity relating to the attachment of ions to aerosol (Ion Sink) was derived from the effective attachment coefficient of the aerosols. Further measurements with the field mill and CPC were taken at the same location in November 2015 when bonfire events would be expected to increase aerosol concentrations. During the summer measurements, particle number count (PNC

  5. Energy Savings and Breakeven Costs for Residential Heat Pump Water Heaters in the United States

    SciTech Connect

    Maguire, Jeff; Burch, Jay; Merrigan, Tim; Ong, Sean

    2013-07-01

    Heat pump water heaters (HPWHs) have recently re-emerged in the U.S. residential water heating market and have the potential to provide homeowners with significant energy savings. However, there are questions as to the actual performance and energy savings potential of these units, in particular in regards to the heat pump's performance in unconditioned space and the impact of the heat pump on space heating and cooling loads when it is located in conditioned space. To help answer these questions, NREL performed simulations of a HPWH in both conditioned and unconditioned space at over 900 locations across the continental United States and Hawaii. Simulations included a Building America benchmark home so that any interaction between the HPWH and the home's HVAC equipment could be captured. Comparisons were performed to typical gas and electric water heaters to determine the energy savings potential and cost effectiveness of a HPWH relative to these technologies. HPWHs were found to have a significant source energy savings potential when replacing typical electric water heaters, but only saved source energy relative to gas water heater in the most favorable installation locations in the southern United States. When replacing an electric water heater, the HPWH is likely to break even in California, the southern United States, and parts of the northeast in most situations. However, the HPWH will only break even when replacing a gas water heater in a few southern states.

  6. Energy Savings and Breakeven Cost for Residential Heat Pump Water Heaters in the United States

    SciTech Connect

    Maguire, J.; Burch, J.; Merrigan, T.; Ong, S.

    2013-07-01

    Heat pump water heaters (HPWHs) have recently reemerged in the U.S. residential water heating market and have the potential to provide homeowners with significant energy savings. However, there are questions as to the actual performance and energy savings potential of these units, in particular in regards to the heat pump's performance in unconditioned space and the impact of the heat pump on space heating and cooling loads when it is located in conditioned space. To help answer these questions, simulations were performed of a HPWH in both conditioned and unconditioned space at over 900 locations across the continental United States and Hawaii. Simulations included a Building America benchmark home so that any interaction between the HPWH and the home's HVAC equipment could be captured. Comparisons were performed to typical gas and electric water heaters to determine the energy savings potential and cost effectiveness of a HPWH relative to these technologies. HPWHs were found to have a significant source energy savings potential when replacing typical electric water heaters, but only saved source energy relative to gas water heater in the most favorable installation locations in the southern US. When replacing an electric water heater, the HPWH is likely to break even in California, the southern US, and parts of the northeast in most situations. However, the HPWH will only break even when replacing a gas water heater in a few southern states.

  7. Potential energy, force distribution and oscillatory motion of chloride ion inside electrically charged carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Sadeghi, F.; Ansari, R.; Darvizeh, M.

    2016-06-01

    In this research, a continuum-based model is presented to explore potential energy, force distribution and oscillatory motion of ions, and in particular chloride ion, inside carbon nanotubes (CNTs) decorated by functional groups at two ends. To perform this, van der Waals (vdW) interactions between ion and nanotube are modeled by the 6-12 Lennard-Jones (LJ) potential, whereas the electrostatic interactions between ion and functional groups are modeled by the Coulomb potential and the total interactions are analytically derived by summing the vdW and electrostatic interactions. Making the assumption that carbon atoms and charge of functional groups are all uniformly distributed over the nanotube surface and the two ends of nanotube, respectively, a continuum approach is utilized to evaluate the related interactions. Based on the actual force distribution, the equation of motion is also solved numerically to arrive at the time history of displacement and velocity of inner core. With respect to the proposed formulations, comprehensive studies on the variations of potential energy and force distribution are carried out by varying functional group charge and nanotube length. Moreover, the effects of these parameters together with initial conditions on the oscillatory behavior of system are studied and discussed in detail. It is found out that chloride ion escapes more easily from negatively charged CNTs which is followed by uncharged and positively charged ones. It is further shown that the presence of functional groups leads to enhancing the operating frequency of such oscillatory systems especially when the electric charges of ion and functional groups have different signs.

  8. Modelling the potential for wind energy integration on China’s coal-heavy electricity grid

    NASA Astrophysics Data System (ADS)

    Davidson, Michael R.; Zhang, Da; Xiong, Weiming; Zhang, Xiliang; Karplus, Valerie J.

    2016-07-01

    Expanding the use of wind energy for electricity generation forms an integral part of China’s efforts to address degraded air quality and climate change. However, the integration of wind energy into China’s coal-heavy electricity system presents significant challenges owing to wind’s variability and the grid’s system-wide inflexibilities. Here we develop a model to predict how much wind energy can be generated and integrated into China’s electricity mix, and estimate a potential production of 2.6 petawatt-hours (PWh) per year in 2030. Although this represents 26% of total projected electricity demand, it is only 10% of the total estimated physical potential of wind resources in the country. Increasing the operational flexibility of China’s coal fleet would allow wind to deliver nearly three-quarters of China’s target of producing 20% of primary energy from non-fossil sources by 2030.

  9. Energy Savings Measure Packages. Existing Homes

    SciTech Connect

    Casey, Sean; Booten, Chuck

    2011-11-01

    This document presents the most cost effective Energy Savings Measure Packages (ESMP) for existing mixed-fuel and all electric homes to achieve 15% and 30% savings for each BetterBuildings grantee location across the United States. These packages are optimized for minimum cost to homeowners for source energy savings given the local climate and prevalent building characteristics (i.e. foundation types). Maximum cost savings are typically found between 30% and 50% energy savings over the reference home; this typically amounts to $300 - $700/year.

  10. Local electrical potential detection of DNA by nanowire-nanopore sensors

    PubMed Central

    Xie, Ping; Xiong, Qihua; Fang, Ying; Qing, Quan; Lieber, Charles M.

    2011-01-01

    Nanopores could potentially be used to perform single molecule DNA sequencing at low cost and with high throughput1–4. Although single-base resolution and differentiation have been demonstrated with nanopores using ionic current measurements5–7, direct sequencing has not been achieved due to difficulties in recording very small (~pA) ionic current at a bandwidth consistent with fast translocation speeds1–3. Here we show that solid-state nanopores can be combined with silicon nanowire field-effect transistors (FETs) to create sensors in which detection is localised and self-aligned at the nanopore. Well-defined FET signals associated with DNA translocation are recorded when an ionic strength gradient is imposed across the nanopores. Measurements and modelling show that FET signals are generated by highly-localized changes in the electrical potential during DNA translocation and that the nanowire-nanopore sensors could enable large-scale integration with a high intrinsic bandwidth. PMID:22157724

  11. Health effects three years after potential exposure to the toxic contaminants of an electrical transformer fire

    SciTech Connect

    Fitzgerald, E.F.; Weinstein, A.L.; Youngblood, L.G.; Standfast, S.J.; Melius, J.M. )

    1989-07-01

    A medical surveillance program has been established for 482 persons who were potentially exposed to polychlorinated biphenyls (PCBs), dibenzo-p-dioxins, and dibenzofurans from an electrical transformer fire in a Binghamton, NY office building in 1981. Vital Record and Cancer Registry data, medical records, and mail questionnaires were used to assess mortality, symptomatology, cancer incidence, and reproductive events through 1984. The numbers of deaths, cancers, fetal deaths, and infants with low birth weight or congenital malformations were similar to those expected on the basis of age- and sex-specific rates for upstate New York and other comparison populations. Two suicides were observed compared with 0.31 expected, but the difference was not statistically significant. After adjustment for possible confounders, persons with the greatest degree of potential exposure were significantly more likely than those with less exposure to report unexplained weight loss (relative risk (RR) = 12.80), muscle pain (RR = 5.07), frequent coughing (RR = 4.14), skin color changes (RR = 3.49), and nervousness or sleep problems (RR = 3.19). The possibility of recall bias and the intervening effects of stress, however, weaken the conclusion that toxic chemicals caused the symptomatology. Exposure-related systemic disorders, e.g., chloracne or peripheral neuropathy, were not diagnosed by personal physicians; however, some persons refused to release their medical records because of ongoing litigation. The findings are consistent with those of our earlier assessment.

  12. Determination of the potential market size and opportunities for biomass to electricity projects in China

    SciTech Connect

    Perlack, R.D.

    1995-08-01

    Efforts are currently underway to assess the market potential and prospects for the US private sector in biomass energy development in Yunnan Province. Among the specific objectives of the study are to: estimate the likely market size and competitiveness of biomass energy, assess the viability of US private sector ventures; assess non-economic factors (e.g., resource, environmental, social, political, institutional) that could affect the viability of biomass energy; and recommend appropriate actions to help stimulate biomass initiatives. Feasibility studies show that biomass projects in Yunnan Province are financially and technically viable. Biomass can be grown and converted to electricity at costs lower than other alternatives. These projects if implemented can ease power shortages and help to sustain the region`s economic growth. The external environmental benefits of integrated biomass projects are also potentially significant. This paper summarizes a two-step screening and rank-ordering process that is being used to identify the best candidate projects for possible US private sector investment. The process uses a set of initial screens to eliminate projects that are not technically feasible to develop. The remaining projects are then rank-ordered using a multicriteria technique.

  13. Evaluating the noise in electrically evoked compound action potential measurements in cochlear implants.

    PubMed

    Undurraga, Jaime A; Carlyon, Robert P; Wouters, Jan; van Wieringen, Astrid

    2012-07-01

    Electrically evoked compound action potentials (ECAPs) are widely used to study the excitability of the auditory nerve and stimulation properties in cochlear implant (CI) users. However, ECAP detection can be difficult and very subjective at near-threshold stimulation levels or in spread of excitation measurements. In this study, we evaluated the statistical properties of the background noise (BN) and the postaverage residual noise (RN) in ECAP measurements in order to determine an objective detection criterion. For the estimation of the BN and the RN, a method currently used in auditory brainstem response measurements was applied. The potential benefit of using weighted (Bayesian) averages was also examined. All estimations were performed with a set of approximately 360 ECAP measurements recorded from five human CI users of the CII or HiRes90K device (advanced bionics). Results demonstrated that the BN was normally distributed and the RN decreased according to the square root of the number of averages. No additional benefit was observed by using weighted averaging. The noise was not significantly different either at different stimulation intensities or across recording electrodes along the cochlea. The analysis of the statistical properties of the noise indicated that a signal-to-noise ratio of 1.7 dB as a detection criterion corresponds to a false positive detection rate of 1% with the used measurement setup.

  14. Atmospheric electric potential gradient measurements of ash clouds generated by pyroclastic flows at Unzen Volcano, Japan

    NASA Astrophysics Data System (ADS)

    Miura, Toshiro; Koyaguchi, Takehiro; Tanaka, Yoshikazu

    Atmospheric electric potential gradient measurements were made at two localities simultaneously during pyroclastic flow events on September 25, 1993 at Unzen volcano. Immediately after generation of the pyroclastic flows, the potential gradients showed a positive anomaly that was followed by a negative anomaly. The magnitude of the positive anomalies were nearly equal at the two measurement localities, whereas the magnitude of the negative anomalies at the measurement locality, close to the axis of the ash cloud, was larger than the magnitude at the off-axis measurement locality. These differences may be accounted for by the differences in the distance between the ash cloud and each measurement locality. It is suggested that the height to the positive charge was sufficiently larger and the height to the negative charge was sufficiently smaller than the horizontal distance between the two measurement localities. Our results suggest that the upper part of the ash cloud, which contained volcanic gases and/or relatively fine ash, carried a net positive charge and the lower part of ash cloud, which contained relatively coarse ash, carried a net negative charge. This charge distribution in the ash clouds generated by pyroclastic flows is more consistent with the results reported for Vulcanian plumes from Sakurajiama volcano [Lane and Gilbert, 1992; Lane et al., 1995] and Asama volcano [Hatakeyama and Ishikawa, 1946] than any other cases.

  15. Evaluation of present thermal barrier coatings for potential service in electric utility gas turbines

    NASA Technical Reports Server (NTRS)

    Bratton, R. J.; Lau, S. K.; Lee, S. Y.

    1982-01-01

    The resistance of present-day thermal barrier coatings to combustion gases found in electric utility turbines was assessed. The plasma sprayed coatings, both duplex and graded types, were primarily zirconia-based, although a calcium silicate was also evaluated. Both atmospheric burner rig tests and high pressure tests (135 psig) showed that several present-day thermal barrier coatings have a high potential for service in gas turbines burning the relatively clean GT No. 2 fuel. However, coating improvements are needed for use in turbines burning lower grade fuel such as residual oil. The duplex ZrO2.8Y2O3/NiCrA1Y coating was ranked highest and selected for near-term field testing, with Ca2SiO4/NiCrA1Y ranked second. Graded coatings show potential for corrosive turbine operating conditions and warrant further development. The coating degradation mechanisms for each coating system subjected to the various environmental conditions are also described.

  16. Health effects three years after potential exposure to the toxic contaminants of an electrical transformer fire.

    PubMed

    Fitzgerald, E F; Weinstein, A L; Youngblood, L G; Standfast, S J; Melius, J M

    1989-01-01

    A medical surveillance program has been established for 482 persons who were potentially exposed to polychlorinated biphenyls (PCBs), dibenzo-p-dioxins, and dibenzofurans from an electrical transformer fire in a Binghamton, NY office building in 1981. Vital Record and Cancer Registry data, medical records, and mail questionnaires were used to assess mortality, symptomatology, cancer incidence, and reproductive events through 1984. The numbers of deaths, cancers, fetal deaths, and infants with low birth weight or congenital malformations were similar to those expected on the basis of age- and sex-specific rates for upstate New York and other comparison populations. Two suicides were observed compared with 0.31 expected, but the difference was not statistically significant. After adjustment for possible confounders, persons with the greatest degree of potential exposure were significantly more likely than those with less exposure to report unexplained weight loss (relative risk [RR] = 12.80), muscle pain (RR = 5.07), frequent coughing (RR = 4.14), skin color changes (RR = 3.49), and nervousness or sleep problems (RR = 3.19). The possibility of recall bias and the intervening effects of stress, however, weaken the conclusion that toxic chemicals caused the symptomatology. Exposure-related systemic disorders, e.g., chloracne or peripheral neuropathy, were not diagnosed by personal physicians; however, some persons refused to release their medical records because of ongoing litigation. The findings are consistent with those of our earlier assessment. PMID:2506840

  17. Turning waste into valuable resource: potential of electric arc furnace dust as photocatalytic material.

    PubMed

    Sapiña, M; Jimenez-Relinque, E; Castellote, M

    2014-10-01

    This paper explores the potential of a hazardous waste of difficult management, electric arc furnace dust (EAFD), as photocatalytic material. Starting from a real waste coming from a Spanish steel factory, chemical, mineralogical, and optical characterizations have been carried out. Direct trials on EAFD and mortar containing this waste have been performed to evaluate its potential as photocatalyst itself and within a cementitious material. The analysis of photocatalytic properties has been done by two different methods: degradation of NO x and degradation of rhodamine (RhB). As a result, it can be said that EAFD exhibited photocatalytic activity for both configurations with UV and visible light, having the mortar enhanced photocatalytic activity for NO x with respect to the EAFD itself. Additionally, in direct trials on the EAFD, it has been able to degrade RhB even in the dark, which has been attributed to transfer of electrons between the adsorbed RhB and the conduction band of some oxides in the dust.

  18. Stability enhancement of an electrically tunable colloidal photonic crystal using modified electrodes with a large electrochemical potential window

    SciTech Connect

    Shim, HongShik; Gyun Shin, Chang; Heo, Chul-Joon; Jeon, Seog-Jin; Jin, Haishun; Woo Kim, Jung; Jin, YongWan; Lee, SangYoon; Gyu Han, Moon E-mail: jinklee@snu.ac.kr; Lim, Joohyun; Lee, Jin-Kyu E-mail: jinklee@snu.ac.kr

    2014-02-03

    The color tuning behavior and switching stability of an electrically tunable colloidal photonic crystal system were studied with particular focus on the electrochemical aspects. Photonic color tuning of the colloidal arrays composed of monodisperse particles dispersed in water was achieved using external electric field through lattice constant manipulation. However, the number of effective color tuning cycle was limited due to generation of unwanted ions by electrolysis of the water medium during electrical switching. By introducing larger electrochemical potential window electrodes, such as conductive diamond-like carbon or boron-doped diamond, the switching stability was appreciably enhanced through reducing the number of ions generated.

  19. Synthesis of novel electrically conducting polymers: Potential conducting Langmuir-Blodgett films and conducting polymers on defined surfaces

    NASA Technical Reports Server (NTRS)

    Zimmer, Hans

    1993-01-01

    Based on previous results involving thiophene derived electrically conducting polymers in which it was shown that thiophene, 3-substituted thiophenes, furans, and certain oligomers of these compounds showed electrical conductivity after polymerization. The conductivity was in the order of up to 500 S/cm. In addition, these polymers showed conductivity without being doped and most of all they were practically inert toward ambient conditions. They even could be used in aqueous media. With these findings as a guide, a number of 3-long-chain-substituted thiophenes and 1-substituted-3-long-chain substituted pyrrols were synthesized as monomers for potential polymeric electrically conducting Langmuir-Blodgett films.

  20. The decision making process regarding the withdrawal or withholding of potential life-saving treatments in a children's hospital

    PubMed Central

    Street, K.; Ashcroft, R.; Henderson, J.; Campbell, A.

    2000-01-01

    Objectives—To investigate the factors considered by staff, and the practicalities involved in the decision making process regarding the withdrawal or withholding of potential life-sustaining treatment in a children's hospital. To compare our current practice with that recommended by the Royal College of Paediatrics and Child Health (RCPCH) guidelines, published in 1997. Design—A prospective, observational study using self-reported questionnaires. Setting—Tertiary paediatric hospital. Patients and participants—Consecutive patients identified during a six-month period, about whom a formal discussion took place between medical staff, nursing staff and family regarding the withholding or withdrawal of potentially life-sustaining treatments. The primary physician and primary nurse involved in the discussion were identified. Method—Two questionnaires completed independently by the primary physician and nurse. Results—Twenty-two patients were identified (median age 1 year; range 1 day—34 years). In 20 cases treatment was withdrawn or withheld, in two cases treatment was continued. Nursing staff considered family wishes and family perceptions of patient suffering as significantly more important factors in decision making than medical staff, who considered prognostic factors as most important. In only two cases were the patient's expressed wishes apparently available. In most cases staff considered the patient's best interests were served and the process would not be enhanced by the involvement of an independent ethics committee. The exceptions were those cases in which treatment was continued following disagreement between parties. Conclusions—Our current practice is consistent with that recommended by the RCPCH. The contribution of the patient, provision of staff counselling and general practitioner (GP) involvement were identified as areas for improvement. Key Words: Withdrawal • limitation • life-sustaining • therapy • treatment PMID:11055037

  1. Respiratory-gated electrical impedance tomography: a potential technique for quantifying stroke volume

    NASA Astrophysics Data System (ADS)

    Arshad, Saaid H.; Murphy, Ethan K.; Halter, Ryan J.

    2016-03-01

    Telemonitoring is becoming increasingly important as the proportion of the population living with cardiovascular disease (CVD) increases. Currently used health parameters in the suite of telemonitoring tools lack the sensitivity and specificity to accurately predict heart failure events, forcing physicians to play a reactive versus proactive role in patient care. A novel cardiac output (CO) monitoring device is proposed that leverages a custom smart phone application and a wearable electrical impedance tomography (EIT) system. The purpose of this work is to explore the potential of using respiratory-gated EIT to quantify stroke volume (SV) and assess its feasibility using real data. Simulations were carried out using the 4D XCAT model to create anatomically realistic meshes and electrical conductivity profiles representing the human thorax and the intrathoracic tissue. A single 5-second period respiration cycle with chest/lung expansion was modeled with end-diastole (ED) and end-systole (ES) heart volumes to evaluate how effective EIT-based conductivity changes represent clinically significant differences in SV. After establishing a correlation between conductivity changes and SV, the applicability of the respiratory-gated EIT was refined using data from the PhysioNet database to estimate the number of useful end-diastole (ED) and end-systole (ES) heart events attained over a 3.3 minute period. The area associated with conductivity changes was found to correlate to SV with a correlation coefficient of 0.92. A window of 12.5% around peak exhalation was found to be the optimal phase of the respiratory cycle from which to record EIT data. Within this window, ~47 useable ED and ES were found with a standard deviation of 28 using 3.3 minutes of data for 20 patients.

  2. Solar wind density controlling penetration electric field at the equatorial ionosphere during a saturation of cross polar cap potential

    NASA Astrophysics Data System (ADS)

    Wei, Y.; Wan, W.; Zhao, B.; Hong, M.; Ridley, A.; Ren, Z.; Fraenz, M.; Dubinin, E.; He, M.

    2012-09-01

    The most important source of electrodynamic disturbances in the equatorial ionosphere during the main phase of a storm is the prompt penetration electric field (PPEF) originating from the high-latitude region. It has been known that such an electric field is correlated with the magnetospheric convection or interplanetary electric field. Here we show a unique case, in which the electric field disturbance in the equatorial ionosphere cannot be interpreted by this concept. During the superstorm on Nov. 20-21, 2003, the cross polar cap potential (CPCP) saturated at least for 8.2 h. The CPCP reconstructed by Assimilative Mapping of Ionospheric Electrodynamics (AMIE) procedure suggested that the PPEF at the equatorial ionosphere still correlated with the saturated CPCP, but the CPCP was controlled by the solar wind density instead of the interplanetary electric field. However, the predicted CPCPs by Hill-Siscoe-Ober (HSO) model and Boyle-Ridley (BR) model were not fully consistent with the AMIE result and PPEF. The PPEF also decoupled from the convection electric field in the magnetotail. Due to the decoupling, the electric field in the ring current was not able to comply with the variations of PPEF, and this resulted in a long-duration electric field penetration without shielding.

  3. Comparison of electrically evoked whole-nerve action potential and electrically evoked auditory brainstem response thresholds in nucleus CI24R cochlear implant recipients.

    PubMed

    Hay-McCutcheon, Marcia J; Brown, Carolyn J; Clay, Kelly Schmidt; Seyle, Keely

    2002-09-01

    In this study, differences between electrically evoked whole-nerve action potential (EAP) and electrically evoked auditory brainstem response (EABR) measurements within Nucleus CI24R cochlear implant recipients were evaluated. Precurved modiolus-hugging internal electrode arrays, such as the CI24R, are designed to provide more direct stimulation of neural elements of the modiolus. If the electrode array is closer to the modiolus, electrically evoked and behavioral levels might be lower than were previously recorded for the straight electrode array, the CI24M. EAP and EABR growth functions and behavioral levels were obtained for 10 postlingually deafened adults. Results revealed no significant differences between EAP and EABR threshold levels, and these levels were not significantly lower than those obtained using the CI24M. PMID:12371659

  4. Calculation of the bidimensional electric potential in a polycrystalline semiconductor Schottky junction

    NASA Astrophysics Data System (ADS)

    Mudrik, M.; Croitoru, N.

    1986-09-01

    In a Schottky p-type polycrystalline junction, two kinds of space-charge layers exist, one due to junction and the other due to the grain boundaries (GB). In such a case, the potential V( x, y) is a solution of a two-dimensional Poisson equation, where x is the distance from the junction and y from the GB. A case is considered where the crystallites are columnar, all the grains are identical, and the doping concentration is N Acm-3. We assume that the GB introduces energy states (i.e. traps) which are equivalent with another effective doping NBcm-3. The existence of a junction perpendicular to the GB causes the width of the GB space charge to decrease. The interaction between the two space charges is expressed by a parameter γ = ( WB0 - WB(0)/ WJ, where W B0 and WB(0) are the widths of the GB space charge without, and with, a Schottky junction, respectively, and W J is the width of the space charge of the junction. The Poisson equation is solved and the potential is V(x,y)= {qN A}/{2ɛ}x 2+ {N B}/{N A}y 2-γ {N B}/{N A}xy- 2W j-γ {N B}/{N A}W 0Bx- {N B}/{N A}[W B(0)+W 0B]y . The term- γqNB xy/2 ɛ appears due to the interaction of both space charges. The electric field, the GB energy barrier and the capacitance are calculated from the potential and are x and y dependent. An equivalent circuit for the distribution of space charges is obtained and could be used in the interpretation of experimental results.

  5. Transepithelial electrical potential of nonsensory region of gerbil utricle in vitro.

    PubMed

    Marcus, D C

    1986-11-01

    Transepithelial electrical potential difference (VT) was measured across the vestibular labyrinth of the inner ear in vitro by puncturing the epithelial wall of the utricle with a glass microelectrode. A region of nonsensory cells of the utricle was isolated from the sensory regions by introducing columns of liquid Sylgard 184. Under control conditions, the VT of this region was +7.5 +/- 0.3 mV (means +/- SE), lumen positive. This potential difference was rapidly reduced by either 1 mM ouabain, 10-100 microM bumetanide, 0.5-5.0 mM Ba (in the bathing solution), or cooling, but not by the disulfonic stilbene, 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid. Changes in VT due to reductions of Cl or Na or to increases of K in the bathing solution in exchange for presumably impermeant ions were observed in this region and were compared with those in a preparation in which the insulating seals were absent. The K-induced voltage change was significantly higher in the unblocked preparation, a finding consistent with a high K permeability of the sensory cells. The voltage change due to reduction of Cl was not inhibited by Cl channel blockers (9-anthracenecarboxylate and diphenylamine-2-carboxylate) in the bathing solution. These results represent the first direct demonstration that the nonsensory cells of the utricle produce a lumen-positive active-transport potential and characterize some of the properties of the cell membranes in terms of their pharmacological sensitivities and net voltage responses to changes in the bathing medium ions Na, K, and Cl.

  6. Electronic structure of a spherical quantum dot: Effects of the Kratzer potential, hydrogenic impurity, external electric and magnetic fields

    NASA Astrophysics Data System (ADS)

    Dehyar, A.; Rezaei, G.; Zamani, A.

    2016-10-01

    In the present work, we have investigated the simultaneous effects of external electric and magnetic fields on the energy spectrum of an electron bound to an impurity confined in a spherical quantum dot with Kratzer potential. To this end, energy eigenvalues are obtained using the asymptotic iteration method. The energy dependencies upon the confinement potential and external fields are reported. Our results indicate that the confinement potential, external electric and magnetic fields have a great influence on the energy eigenvalues of the system. We found that, an increase in the magnetic field increases the energy eigenvalues of the states with positive magnetic quantum number, m ≽ 0 . While, the states with negative m decrease, reaching to their minimum values and increase again, with increasing the magnetic field. Moreover, an increase in electric field strength leads to decrease the confinement effects and energy eigenvalues of the system.

  7. Numerical Computation of Electric Field and Potential Along Silicone Rubber Insulators Under Contaminated and Dry Band Conditions

    NASA Astrophysics Data System (ADS)

    Arshad; Nekahi, A.; McMeekin, S. G.; Farzaneh, M.

    2016-09-01

    Electrical field distribution along the insulator surface is considered one of the important parameters for the performance evaluation of outdoor insulators. In this paper numerical simulations were carried out to investigate the electric field and potential distribution along silicone rubber insulators under various polluted and dry band conditions. Simulations were performed using commercially available simulation package Comsol Multiphysics based on the finite element method. Various pollution severity levels were simulated by changing the conductivity of pollution layer. Dry bands of 2 cm width were inserted at the high voltage end, ground end, middle part, shed, sheath, and at the junction of shed and sheath to investigate the effect of dry band location and width on electric field and potential distribution. Partial pollution conditions were simulated by applying pollution layer on the top and bottom surface respectively. It was observed from the simulation results that electric field intensity was higher at the metal electrode ends and at the junction of dry bands. Simulation results showed that potential distribution is nonlinear in the case of clean and partially polluted insulator and linear for uniform pollution layer. Dry band formation effect both potential and electric field distribution. Power dissipated along the insulator surface and the resultant heat generation was also studied. The results of this study could be useful in the selection of polymeric insulators for contaminated environments.

  8. Rhythmicity in the protoplasmic streaming of a slime mold, Physarum polycephalum. II. Theoretical treatment of the electric potential rhythm.

    PubMed

    KISHIMOTO, U

    1958-07-20

    The electric potential difference (1 to 15 mv.) between two loci of the slime mold connected with a strand of protoplasm changes rhythmically with the same period (60 to 180 seconds) as that of back and forth protoplasmic streaming along the strand. When atmospheric pressure at a part of the plasmodium is increased (about 10 cm. H(2)O), the electric potential at this part becomes positive (0 to 20 mv.) to another part with a time constant of 2 to 15 minutes. If the atmospheric pressure at a part of the plasmodium is changed (about 10 cm. H(2)O) periodically, the electric potential rhythm also changes with the same period as that of the applied pressure change, and the amplitude of the former grows to a new level (i.e., forced oscillation). The electric potential rhythm, in this case, is generally delayed about 90 degrees in phase angle from the external pressure change. The period of the electric potential rhythm which coincided with that of the pressure change is maintained for a while after stopping the application of the pressure change, if the period is not much different from the native flow rhythm. Such a pressure effect is brought about by the forced transport of protoplasm and is reversible as a rule. In the statistical analysis made by Kishimoto (1958) and in the rheological treatment made in the report, the rhythmic deformation of the contractile protein networks is supposed to be the cause of the protoplasmic flow along the strand and of the electric potential rhythm. The role of such submicroscopic networks in the protoplasm in various kinds of protoplasmic movement is emphasized.

  9. The Potential Economic Impact of Electricity Restructuring in the State of Oklahoma: Phase II Report

    SciTech Connect

    Hadley, SW

    2001-10-30

    Because of the recent experiences of several states undergoing restructuring (e.g., higher prices, greater volatility, lower reliability), concerns have been raised in states currently considering restructuring as to whether their systems are equally vulnerable. Factors such as local generation costs, transmission constraints, market concentration, and market design can all play a role in the success or failure of the market. These factors along with the mix of generation capacity supplying the state will influence the relative prices paid by consumers. The purpose of this project is to provide a model and process to evaluate the potential price and economic impacts of restructuring the Oklahoma electric industry. The Phase I report concentrated on providing an analysis of the Oklahoma system in the near-term, using only present generation resources and customer demands. This Phase II study analyzed the Oklahoma power market in 2010, incorporating the potential of new generation resources and customer responses. Five key findings of this Phase II were made: (1) Projected expansion in generating capacity exceeds by over 3,000 MW the demands within the state plus the amount that could be exported with the current transmission system. (2) Even with reduced new plant construction, most new plants could lose money (although residential consumers would see lower rates) unless they have sufficient market power to raise their prices without losing significant market share (Figure S-1). (3) If new plants can raise prices to stay profitable, existing low-cost coal and hydro plants will have very high profits. Average prices to customers could be 5% to 25% higher than regulated rates (Figure S-1). If the coal and hydro plants are priced at cost-based rates (through long-term contracts or continued regulation) while all other plants use market-based rates then prices are lower. (4) Customer response to real-time prices can lower the peak capacity requirements by around 9

  10. Meeting the Challenge: The Prospect of Achieving 30 Percent Savings Through the Weatherization Assistance Program

    SciTech Connect

    Schweitzer, M.

    2002-05-31

    The U.S. Department of Energy's (DOE's) Weatherization Assistance Program has been installing energy-efficiency measures in low-income houses for over 25 years, achieving savings exceeding 30 percent of natural gas used for space heating. Recently, as part of its Weatherization Plus initiative, the Weatherization Assistance Program adopted the goal of achieving 30 percent energy savings for all household energy usage. The expansion of the Weatherization Assistance Program to include electric baseload components such as lighting and refrigerators provides additional opportunities for saving energy and meeting this ambitious goal. This report documents an Oak Ridge National Laboratory study that examined the potential savings that could be achieved by installing various weatherization measures in different types of dwellings throughout the country. Three different definitions of savings are used: (1) reductions in pre-weatherization expenditures; (2) savings in the amount of energy consumed at the house site, regardless of fuel type (''site Btus''); and (3) savings in the total amount of energy consumed at the source (''source Btus''), which reflects the fact that each Btu* of electricity consumed at the household level requires approximately three Btus to produce at the generation source. In addition, the effects of weatherization efforts on carbon dioxide (CO{sub 2}) emissions are examined.

  11. Estimation of breast dose saving potential using a breast positioning technique for organ-based tube current modulated CT

    NASA Astrophysics Data System (ADS)

    Fu, Wanyi; Tian, Xiaoyu; Sturgeon, Gregory; Agasthya, Greeshma; Segars, William Paul; Goodsitt, Mitchell M.; Kazerooni, Ella A.; Samei, Ehsan

    2016-04-01

    In thoracic CT, organ-based tube current modulation (OTCM) reduces breast dose by lowering the tube current in the 120° anterior dose reduction zone of patients. However, in practice the breasts usually expand to an angle larger than the dose reduction zone. This work aims to simulate a breast positioning technique (BPT) to constrain the breast tissue to within the dose reduction zone for OTCM and to evaluate the corresponding potential reduction in breast dose. Thirteen female anthropomorphic computational phantoms were studied (age range: 27-65 y.o., weight range: 52-105.8 kg). Each phantom was modeled in the supine position with and without application of the BPT. Attenuation-based tube current (ATCM, reference mA) was generated by a ray-tracing program, taking into account the patient attenuation change in the longitudinal and angular plane (CAREDose4D, Siemens Healthcare). OTCM was generated by reducing the mA to 20% between +/- 60° anterior of the patient and increasing the mA in the remaining projections correspondingly (X-CARE, Siemens Healthcare) to maintain the mean tube current. Breast tissue dose was estimated using a validated Monte Carlo program for a commercial scanner (SOMATOM Definition Flash, Siemens Healthcare). Compared to standard tube current modulation, breast dose was significantly reduced using OTCM by 19.8+/-4.7%. With the BPT, breast dose was reduced by an additional 20.4+/-6.5% to 37.1+/-6.9%, using the same CTDIvol. BPT was more effective for phantoms simulating women with larger breasts with the average breast dose reduction of 30.2%, 39.2%, and 49.2% from OTCMBP to ATCM, using the same CTDIvol for phantoms with 0.5, 1.5, and 2.5 kg breasts, respectively. This study shows that a specially designed BPT improves the effectiveness of OTCM.

  12. Exploring new scaling regimes for streaming potential and electroviscous effects in a nanocapillary with overlapping electric double layers.

    PubMed

    Das, Siddhartha; Guha, Arnab; Mitra, Sushanta K

    2013-12-01

    In this paper, we unravel new scaling regimes for streaming potential and electroviscous effects in a nanocapillary with thick overlapping Electric Double Layers (EDLs). We observe that the streaming potential, for a given value of the capillary zeta (ζ) potential, varies with the EDL thickness and a dimensionless parameter R, quantifying the conduction current. Depending on the value of R, variation of the streaming potential with the EDL thickness demonstrates distinct scaling regimes: one can witness a Quadratic Regime where the streaming potential varies as the square of the EDL thickness, a Weak Regime where the streaming potential shows a weaker variation with the EDL thickness, and a Saturation Regime where the streaming potential ceases to vary with the EDL thickness. Effective viscosity, characterizing the electroviscous effect, obeys the variation of the streaming potential for smaller EDL thickness values; however, for larger EDL thickness the electroosmotic flow profile dictates the electroviscous effect, with insignificant contribution of the streaming potential.

  13. Relationships Between Electrical Conductivity - Water Content, Water Potential and Unsaturated Hydraulic Conductivity for Three Soils

    NASA Astrophysics Data System (ADS)

    Ruy, S.; Doussan, C.

    2006-05-01

    In soil physics, water retention and hydraulic conductivity are key parameters for predicting water fluxes in soils. Determination of these hydrodynamic characteristics in the lab, particularly unsaturated hydraulic conductivity, is most often complicated, time consuming and error-prone. These difficulties often prohibit the examination of numerous soil samples for determining these parameters as would be necessary to get a good estimation of the field variability. In this case, an indirect and easy to measure variable, closely linked to water retention or hydraulic conductivity, would be helpful in the assessment of these parameters. Electrical conductivity (EC) is a good candidate for such a variable because, in a porous medium, its magnitude is largely determined by the number of water filled pores and their connectivity. Relationships between water content (or saturation) and EC have been established both from empirical or theoretical point of view for some time. However, relationships between EC and unsaturated hydraulic conductivity are much more scarce, as are experimental data. We present relationships between EC and water content or water potential for three soil types: a clay loam, a sandy loam and a sand. We also present experimental relationships between EC and unsaturated hydraulic conductivity. The soil were cored undisturbed in the field and water retention was measured together with E. Hydraulic conductivity was calculated from the Wind evaporation method and from steady state measurements for low suctions. Mercury porosimetry measurements were also performed after the experiments. Water saturation reasonably follows a power-law relationship with relative EC (EC/ECsat). Exponents of the power law being around 3 - 3.5 for the clay loam, 1.1 - 1.7 for the sandy loam and 8 - 12 for the sand (for matric potentials between 0 and -80 cm in the latter case). Variation of the relative EC with the log of water potential shows a S-shape, with an almost linear

  14. Electrically Elicited Visual Evoked Potentials in Argus II Retinal Implant Wearers

    PubMed Central

    Stronks, H. Christiaan; Barry, Michael P.; Dagnelie, Gislin

    2013-01-01

    Purpose. We characterized electrically elicited visual evoked potentials (eVEPs) in Argus II retinal implant wearers. Methods. eVEPs were recorded in four subjects, and analyzed by determining amplitude and latency of the first two positive peaks (P1 and P2). Subjects provided subjective feedback by rating the brightness and size of the phosphenes. We established eVEP input–output relationships, eVEP variability between and within subjects, the effect of stimulating different areas of the retina, and the maximal pulse rate to record eVEPs reliably. Results. eVEP waveforms had low signal-to-noise ratios, requiring long recording times and substantial signal processing. Waveforms varied between subjects, but showed good reproducibility and consistent parameter dependence within subjects. P2 amplitude overall was the most robust outcome measure and proved an accurate indicator of subjective threshold. Peak latencies showed small within-subject variability, yet their correlation with stimulus level and subjective rating were more variable than that of peak amplitudes. Pulse rates of up to 2/3 Hz resulted in reliable eVEP recordings. Perceived phosphene brightness declined over time, as reflected in P1 amplitude, but not in P2 amplitude or peak latencies. Stimulating-electrode location significantly affected P1 and P2 amplitude and latency, but not subjective percepts. Conclusions. While recording times and signal processing are more demanding than for standard visually evoked potential (VEP) recordings, the eVEP has proven to be a reliable tool to verify retinal implant functionality. eVEPs correlated with various stimulus parameters and with perceptual ratings. In view of these findings, eVEPs may become an important tool in functional investigations of retinal prostheses. (ClinicalTrials.gov number NCT00407602.) Dutch Abstract PMID:23611993

  15. Brain potentials evoked by intraepidermal electrical stimuli reflect the central sensitization of nociceptive pathways

    PubMed Central

    Lee, M. C.; O'Neill, J.; Dickenson, A. H.; Iannetti, G. D.

    2016-01-01

    Central sensitization (CS), the increased sensitivity of the central nervous system to somatosensory inputs, accounts for secondary hyperalgesia, a typical sign of several painful clinical conditions. Brain potentials elicited by mechanical punctate stimulation using flat-tip probes can provide neural correlates of CS, but their signal-to-noise ratio is limited by poor synchronization of the afferent nociceptive input. Additionally, mechanical punctate stimulation does not activate nociceptors exclusively. In contrast, low-intensity intraepidermal electrical stimulation (IES) allows selective activation of type II Aδ-mechano-heat nociceptors (II-AMHs) and elicits reproducible brain potentials. However, it is unclear whether hyperalgesia from IES occurs and coexists with secondary mechanical punctate hyperalgesia, and whether the magnitude of the electroencephalographic (EEG) responses evoked by IES within the hyperalgesic area is increased. To address these questions, we explored the modulation of the psychophysical and EEG responses to IES by intraepidermal injection of capsaicin in healthy human subjects. We obtained three main results. First, the intensity of the sensation elicited by IES was significantly increased in participants who developed robust mechanical punctate hyperalgesia after capsaicin injection (i.e., responders), indicating that hyperalgesia from IES coexists with punctate mechanical hyperalgesia. Second, the N2 peak magnitude of the EEG responses elicited by IES was significantly increased after the intraepidermal injection of capsaicin in responders only. Third, a receiver-operator characteristics analysis showed that the N2 peak amplitude is clearly predictive of the presence of CS. These findings suggest that the EEG responses elicited by IES reflect secondary hyperalgesia and therefore represent an objective correlate of CS. PMID:27098022

  16. Brain potentials evoked by intraepidermal electrical stimuli reflect the central sensitization of nociceptive pathways.

    PubMed

    Liang, M; Lee, M C; O'Neill, J; Dickenson, A H; Iannetti, G D

    2016-08-01

    Central sensitization (CS), the increased sensitivity of the central nervous system to somatosensory inputs, accounts for secondary hyperalgesia, a typical sign of several painful clinical conditions. Brain potentials elicited by mechanical punctate stimulation using flat-tip probes can provide neural correlates of CS, but their signal-to-noise ratio is limited by poor synchronization of the afferent nociceptive input. Additionally, mechanical punctate stimulation does not activate nociceptors exclusively. In contrast, low-intensity intraepidermal electrical stimulation (IES) allows selective activation of type II Aδ-mechano-heat nociceptors (II-AMHs) and elicits reproducible brain potentials. However, it is unclear whether hyperalgesia from IES occurs and coexists with secondary mechanical punctate hyperalgesia, and whether the magnitude of the electroencephalographic (EEG) responses evoked by IES within the hyperalgesic area is increased. To address these questions, we explored the modulation of the psychophysical and EEG responses to IES by intraepidermal injection of capsaicin in healthy human subjects. We obtained three main results. First, the intensity of the sensation elicited by IES was significantly increased in participants who developed robust mechanical punctate hyperalgesia after capsaicin injection (i.e., responders), indicating that hyperalgesia from IES coexists with punctate mechanical hyperalgesia. Second, the N2 peak magnitude of the EEG responses elicited by IES was significantly increased after the intraepidermal injection of capsaicin in responders only. Third, a receiver-operator characteristics analysis showed that the N2 peak amplitude is clearly predictive of the presence of CS. These findings suggest that the EEG responses elicited by IES reflect secondary hyperalgesia and therefore represent an objective correlate of CS.

  17. Coarse-Grained Modeling of Nucleic Acids Using Anisotropic Gay-Berne and Electric Multipole Potentials.

    PubMed

    Li, Guohui; Shen, Hujun; Zhang, Dinglin; Li, Yan; Wang, Honglei

    2016-02-01

    In this work, we attempt to apply a coarse-grained (CG) model, which is based on anisotropic Gay-Berne and electric multipole (EMP) potentials, to the modeling of nucleic acids. First, a comparison has been made between the CG and atomistic models (AMBER point-charge model) in the modeling of DNA and RNA hairpin structures. The CG results have demonstrated a good quality in maintaining the nucleic acid hairpin structures, in reproducing the dynamics of backbone atoms of nucleic acids, and in describing the hydrogen-bonding interactions between nucleic acid base pairs. Second, the CG and atomistic AMBER models yield comparable results in modeling double-stranded DNA and RNA molecules. It is encouraging that our CG model is capable of reproducing many elastic features of nucleic acid base pairs in terms of the distributions of the interbase pair step parameters (such as shift, slide, tilt, and twist) and the intrabase pair parameters (such as buckle, propeller, shear, and stretch). Finally, The GBEMP model has shown a promising ability to predict the melting temperatures of DNA duplexes with different lengths.

  18. Potential therapeutic mechanism of extremely low-frequency high-voltage electric fields in cells.

    PubMed

    Kim, Ka-Eun; Park, Soon-Kwon; Nam, Sang-Yun; Han, Tae-Jong; Cho, Il-Young

    2016-05-18

    The aim of this survey was to provide background theory based on previous research to elucidate the potential pathway by which medical devices using extremely low-frequency high-voltage electric fields (ELF-HVEF) exert therapeutic effects on the human body, and to increase understanding of the AC high-voltage electrotherapeutic apparatus for consumers and suppliers of the relevant devices. Our review revealed that an ELF field as weak as 1-10 μ V/m can induce diverse alterations of membrane proteins such as transporters and channel proteins, including changes in Ca + + binding to a specific site of the cell surface, changes in ion (e.g., Ca + + ) influx or efflux, and alterations in the ligand-receptor interaction. These alterations then induce cytoplasmic responses within cells (Ca + + , cAMP, kinases, etc.) that can have impacts on cell growth, differentiation, and other functional properties by promoting the synthesis of macromolecules. Moreover, increased cytoplasmic Ca + + involves calmodulin-dependent signaling and consequent Ca + + /calmodulin-dependent stimulation of nitric oxide synthesis. This event in turn induces the nitric oxide-cGMP-protein kinase G pathway, which may be an essential factor in the observed physiological and therapeutic responses.

  19. Simulation of Electric Potentials and Ion Motion in Planar Electrode Structures for Lossless Ion Manipulations (SLIM)

    SciTech Connect

    Garimella, Sandilya V. B; Ibrahim, Yehia M.; Webb, Ian K.; Tolmachev, Aleksey V.; Zhang, Xinyu; Prost, Spencer A.; Anderson, Gordon A.; Smith, Richard D.

    2014-09-26

    Here we report a conceptual study and computational evaluation of novel planar electrode Structures for Lossless Ion Manipulations (SLIM). Planar electrode SLIM devices were designed that allow for flexible ion confinement, transport and storage using a combination of RF and DC fields. Effective potentials can be generated that provide near ideal regions for confining ions in the presence of a gas. Ion trajectory simulations using SIMION 8.1 demonstrated the capability for lossless ion motion in these devices over a wide m/z range and a range of electric fields at low pressures (e.g. a few torr). More complex ion manipulations, e.g. turning ions by 90° and dynamically switching selected ion species into orthogonal channels, are also feasible. Lastly, the performance of SLIM devices at ~4 torr pressure for performing ion mobility based separations (IMS) is computationally evaluated and compared to initial experimental results, and both of which agree closely with experimental and theoretical IMS performance for a conventional drift tube design.

  20. Simulation of Electric Potentials and Ion Motion in Planar Electrode Structures for Lossless Ion Manipulations (SLIM)

    DOE PAGES

    Garimella, Sandilya V. B; Ibrahim, Yehia M.; Webb, Ian K.; Tolmachev, Aleksey V.; Zhang, Xinyu; Prost, Spencer A.; Anderson, Gordon A.; Smith, Richard D.

    2014-09-26

    Here we report a conceptual study and computational evaluation of novel planar electrode Structures for Lossless Ion Manipulations (SLIM). Planar electrode SLIM devices were designed that allow for flexible ion confinement, transport and storage using a combination of RF and DC fields. Effective potentials can be generated that provide near ideal regions for confining ions in the presence of a gas. Ion trajectory simulations using SIMION 8.1 demonstrated the capability for lossless ion motion in these devices over a wide m/z range and a range of electric fields at low pressures (e.g. a few torr). More complex ion manipulations, e.g.more » turning ions by 90° and dynamically switching selected ion species into orthogonal channels, are also feasible. Lastly, the performance of SLIM devices at ~4 torr pressure for performing ion mobility based separations (IMS) is computationally evaluated and compared to initial experimental results, and both of which agree closely with experimental and theoretical IMS performance for a conventional drift tube design.« less

  1. Coarse-Grained Modeling of Nucleic Acids Using Anisotropic Gay-Berne and Electric Multipole Potentials.

    PubMed

    Li, Guohui; Shen, Hujun; Zhang, Dinglin; Li, Yan; Wang, Honglei

    2016-02-01

    In this work, we attempt to apply a coarse-grained (CG) model, which is based on anisotropic Gay-Berne and electric multipole (EMP) potentials, to the modeling of nucleic acids. First, a comparison has been made between the CG and atomistic models (AMBER point-charge model) in the modeling of DNA and RNA hairpin structures. The CG results have demonstrated a good quality in maintaining the nucleic acid hairpin structures, in reproducing the dynamics of backbone atoms of nucleic acids, and in describing the hydrogen-bonding interactions between nucleic acid base pairs. Second, the CG and atomistic AMBER models yield comparable results in modeling double-stranded DNA and RNA molecules. It is encouraging that our CG model is capable of reproducing many elastic features of nucleic acid base pairs in terms of the distributions of the interbase pair step parameters (such as shift, slide, tilt, and twist) and the intrabase pair parameters (such as buckle, propeller, shear, and stretch). Finally, The GBEMP model has shown a promising ability to predict the melting temperatures of DNA duplexes with different lengths. PMID:26717419

  2. Simulation of Electric Potentials and Ion Motion in Planar Electrode Structures for Lossless Ion Manipulations (SLIM)

    PubMed Central

    Garimella, Sandilya V.B.; Ibrahim, Yehia M.; Webb, Ian K.; Tolmachev, Aleksey V.; Zhang, Xinyu; Prost, Spencer A.; Anderson, Gordon A.; Smith, Richard D.

    2014-01-01

    We report a conceptual study and computational evaluation of novel planar electrode Structures for Lossless Ion Manipulations (SLIM). Planar electrode SLIM devices were designed that allow for flexible ion confinement, transport and storage using a combination of RF and DC fields. Effective potentials can be generated that provide near ideal regions for confining and manipulating ions in the presence of a gas. Ion trajectory simulations using SIMION 8.1 demonstrated the capability for lossless ion motion in these devices over a wide m/z range and a range of electric fields at low pressures (e.g. a few torr). More complex ion manipulations, e.g. turning ions by 90° and dynamically switching selected ion species into orthogonal channels, are also shown feasible. The performance of SLIM devices at ~4 torr pressure for performing ion mobility based separations (IMS) is computationally evaluated and compared to initial experimental results, and both of which are also shown to agree closely with experimental and theoretical IMS performance for a conventional drift tube design. PMID:25257188

  3. Effects of cell orientation and electric field frequency on the transmembrane potential induced in ellipsoidal cells.

    PubMed

    Maswiwat, Kanokkan; Wachner, Derk; Gimsa, Jan

    2008-11-01

    The transmembrane potential (Deltaphi) induced by external electric fields is important both in biotech applications and in new medical therapies. We analyzed the effects of AC field frequency and cell orientation for cells of a general ellipsoidal shape. Simplified equations were derived for the membrane surface points where the maximum Deltaphi is induced. The theoretical results were confirmed in experiments with three-axial chicken red blood cells (a:b:c=6.66 microm:4.17 microm:1.43 microm). Propidium iodide (PI) staining and cell lysis were detected after an AC electropermeabilization (EP) pulse. The critical field strength for both effects increased when the shorter axis of a cell was parallel to the field, as well as at higher field frequency and for shorter pulse durations. Nevertheless, data analysis based on our theoretical description revealed that the Deltaphi required is lower for the shorter axis, i.e. for smaller membrane curvatures. The critical Deltaphi was independent of the field frequency for a given axis, i.e. the field strength had to be increased with frequency to compensate for the membrane dispersion effect. Comparison of the critical field strengths of PI staining in a linear field aligned along semi-axis a (142 kV m(-1)) and a field rotating in the a-b plane (115 kV m(-1)) revealed the higher EP efficiency of rotating fields.

  4. Self-consistent analyses for potential conduction block in nerves by an ultrashort high-intensity electric pulse

    NASA Astrophysics Data System (ADS)

    Joshi, R. P.; Mishra, A.; Hu, Q.; Schoenbach, K. H.; Pakhomov, A.

    2007-06-01

    Simulation studies are presented that probe the possibility of using high-field (>100kV/cm) , short-duration (˜50ns) electrical pulses for nonthermal and reversible cessation of biological electrical signaling pathways. This would have obvious applications in neurophysiology, clinical research, neuromuscular stimulation therapies, and even nonlethal bioweapons development. The concept is based on the creation of a sufficiently high density of pores on the nerve membrane by an electric pulse. This modulates membrane conductance and presents an effective “electrical short” to an incident voltage wave traveling across a nerve. Net blocking of action potential propagation can then result. A continuum approach based on the Smoluchowski equation is used to treat electroporation. This is self-consistently coupled with a distributed circuit representation of the nerve dynamics. Our results indicate that poration at a single neural segment would be sufficient to produce an observable, yet reversible, effect.

  5. Electrochemical and structural properties of the electrical double layer of two-component electrolytes in response to varied electrode potential

    NASA Astrophysics Data System (ADS)

    Kiyohara, Kenji; Yamagata, Masaki; Ishikawa, Masashi

    2016-04-01

    The electrochemical and structural properties of the electrical double layers for two-component electrolytes were studied by Monte Carlo simulations using simple models. When the electrolyte contains two species of cations that have different diameters, the capacitance on the cathode dramatically increases as a large negative potential is applied. This behavior is qualitatively similar to the one reported in an experimental work that has used Li-containing ionic liquid as the electrolyte [M. Yamagata et al., Electrochim. Acta 110, 181-190 (2013)], in which it has also been reported that addition of Li ions to the electrolyte enhances the potential window to the negative side. The analysis of the ionic structure showed that the electrical double layer on the cathode is dominantly formed by the larger cations under small negative potentials, while they are replaced by the smaller cations under large negative potentials. This transition of the ionic structure with electrode potential is also consistent with the enhancement of the potential window that was found in the experimental work, which suggests that the organic cations are expelled from the electrical double layer under large negative potentials and the chance of decomposition is reduced.

  6. Potential reduction of DSN uplink energy cost

    NASA Technical Reports Server (NTRS)

    Dolinsky, S.; Degroot, N. F.

    1982-01-01

    DSN Earth stations typically transmit more power than that required to meet minimum specifications for uplink performance. Energy and cost savings that could result from matching the uplink power to the amount required for specified performance are studied. The Galileo mission was selected as a case study. Although substantial reduction in transmitted energy is possible, potential savings in source energy (oil or electricity) savings are much less. This is because of the rising inefficiency in power conversion and radio frequency power generation that accompanies reduced power output.

  7. Potential impacts of electric power production utilizing natural gas, renewables and carbon capture and sequestration on US Freshwater resources.

    PubMed

    Tidwell, Vincent C; Malczynski, Leonard A; Kobos, Peter H; Klise, Geoffrey T; Shuster, Erik

    2013-08-01

    Carbon capture and sequestration (CCS) has important implications relative to future thermoelectric water use. A bounding analysis is performed using past greenhouse gas emission policy proposals and assumes either all effected capacity retires (lower water use bound) or is retrofitted (upper bound). The analysis is performed in the context of recent trends in electric power generation expansion, namely high penetration of natural gas and renewables along with constrained cooling system options. Results indicate thermoelectric freshwater withdrawals nationwide could increase by roughly 1% or decrease by up to 60% relative to 2009 levels, while consumption could increase as much as 21% or decrease as much as 28%. To identify where changes in freshwater use might be problematic at a regional level, electric power production has been mapped onto watersheds with limited water availability (where consumption exceeds 70% of gauged streamflow). Results suggest that between 0.44 and 0.96 Mm(3)/d of new thermoelectric freshwater consumption could occur in watersheds with limited water availability, while power plant retirements in these watersheds could yield 0.90 to 1.0 Mm(3)/d of water savings.

  8. Application of vertical electrical sounding (VES) in subsurface geological investigation for potential aquifer in Lahad Datu, Sabah

    NASA Astrophysics Data System (ADS)

    Saleh, Hardianshah; Samsudin, Abdul Rahim

    2013-11-01

    40 Vertical Electrical Sounding (VES) stations were established to investigate the subsurface geology and aquifer potentials in the area of Dent Group sedimentary rock. Dent Group sedimentary rock consists of Sebahat, Ganduman and Togopi Formation with the age of Late Miocene until Pleistocene. VES technique was performed by measuring the resistivity change with depth. The resistivity measurements were conducted using ABEM SAS 300C Terrameter by using Schlumberger electrode configuration with maximum current electrode separation of 500m. Interpreted VES data in the Sebahat Formation produces three to four geo-electrical resistivity layers. Most of the geo-electrical layers show low resistivity value (1-10 Ohm-m) that indicate the formation was mainly made of clay or shale materials. VES results in the Ganduman Formation indicates that the formation dominated by layers of sandstone and mudstone mixed with siltstone layer. Generally, the Ganduman Formation gives four to five geo-electrical resistivity layers. While Togopi Formation produced 3 to 4 geo-electrical layers interpreted as sandstone for the first layer, mudstone for the second layer and followed by layer containing several block of limestone. The geo-electrical resistivity results indicate that Ganduman and Togopi Formations have the potential to become aquifer. The VES method has successfully detected the soil material layers in Ganduman and Togopi formations which were supported by the existing borehole data. Combination of sandstone and mudstone layers indicate that the Ganduman Formation possibly become semi-confined aquifer. Furthermore, the Ganduman Formation also producing artesian wells in some areas that were found at a number of production wells in the study area. Similarly, the Togopi Formation is also having dominated sandy layer that can be a potential aquifer. In addition, the limestone blocks in the Togopi Formation could also become a potential aquifer, whilst for the Sebahat Formation

  9. Energy conservation in electric distribution

    SciTech Connect

    Lee, Chong-Jin

    1994-12-31

    This paper discusses the potential for energy and power savings that exist in electric power delivery systems. These savings translate into significant financial and environmental benefits for electricity producers and consumers as well as for society in general. AlliedSignal`s knowledge and perspectives on this topic are the result of discussions with hundreds of utility executives, government officials and other industry experts over the past decade in conjunction with marketing our Amorphous Metal technology for electric distribution transformers. Amorphous metal is a technology developed by AlliedSignal that significantly reduces the energy lost in electric distribution transformers at an incremental cost of just a few cents per kilo-Watt-hour. The purpose of this paper is to discuss: Amorphous Metal Alloy Technology; Energy Savings Opportunity; The Industrial Barriers and Remedies; Worldwide Demand; and A Low Risk Strategy. I wish this presentation will help KEPCO achieve their stated aims of ensuring sound development of the national economy and enhancement of public life through the economic and stable supply of electric power. AlliedSignal Korea Ltd. in conjunction with AlliedSignal Amorphous Metals in the U.S. are here to work with KEPCO, transformer manufacturers, industry, and government agencies to achieve greater efficiency in power distribution.

  10. Rhythmicity in the protoplasmic streaming of a slime mold, Physarum polycephalum. I. A statistical analysis of the electric potential rhythm.

    PubMed

    KISHIMOTO, U

    1958-07-20

    The electric potential difference (1 to 15 mv.) between two loci of the slime mold connected with a strand of protoplasm changes rhythmically with the same period (60 to 180 seconds) as that of the back and forth protoplasmic streaming along the strand. Generally some phase difference is observed between them. Periods of the electric potential rhythm show a Gaussian distribution. Amplitudes give a somewhat different distribution curve. Wave forms are not always simple harmonic ones, but are distorted more or less. However, auto-correlation analysis proves that there is a dominant rhythm of a nearly constant period which coincides with the mean period of the Gaussian distribution curve. Calculations made on an assumption that the electric potential rhythm is the result of many elementary rhythms (i.e., same periodicity, arbitrary phase angles) distributed throughout the plasmodium, give a satisfactory coincidence with the observed distribution for the amplitude. The predominance of a rhythm of a nearly constant periodicity suggests the existence of well organized interactions among components of a contractile protein network, the rhythmic deformation of which is supposed to be responsible for the protoplasmic streaming and for the electric potential rhythm.

  11. The Confidence-Accuracy Relationship in Diagnostic Assessment: The Case of the Potential Difference in Parallel Electric Circuits

    ERIC Educational Resources Information Center

    Saglam, Murat

    2015-01-01

    This study explored the relationship between accuracy of and confidence in performance of 114 prospective primary school teachers in answering diagnostic questions on potential difference in parallel electric circuits. The participants were required to indicate their confidence in their answers for each question. Bias and calibration indices were…

  12. Relationship between pore size and reversible and irreversible immobilization of ionic liquid electrolytes in porous carbon under applied electric potential

    NASA Astrophysics Data System (ADS)

    Mahurin, Shannon M.; Mamontov, Eugene; Thompson, Matthew W.; Zhang, Pengfei; Turner, C. Heath; Cummings, Peter T.; Dai, Sheng

    2016-10-01

    Transport of electrolytes in nanoporous carbon-based electrodes largely defines the function and performance of energy storage devices. Using molecular dynamics simulation and quasielastic neutron scattering, we investigate the microscopic dynamics of a prototypical ionic liquid electrolyte, [emim][Tf2N], under applied electric potential in carbon materials with 6.7 nm and 1.5 nm pores. The simulations demonstrate the formation of dense layers of counter-ions near the charged surfaces, which is reversible when the polarity is reversed. In the experiment, the ions immobilized near the surface manifest themselves in the elastic scattering signal. The experimentally observed ion immobilization near the wall is fully reversible as a function of the applied electric potential in the 6.7 nm, but not in the 1.5 nm nanopores. In the latter case, remarkably, the first application of the electric potential leads to apparently irreversible immobilization of cations or anions, depending on the polarity, near the carbon pore walls. This unexpectedly demonstrates that in carbon electrode materials with the small pores, which are optimal for energy storage applications, the polarity of the electrical potential applied for the first time after the introduction of an ionic liquid electrolyte may define the decoration of the small pore walls with ions for prolonged periods of time and possibly for the lifetime of the electrode.

  13. Relationship between pore size and reversible and irreversible immobilization of ionic liquid electrolytes in porous carbon under applied electric potential

    DOE PAGES

    Mahurin, Shannon M.; Mamontov, Eugene; Thompson, Matthew W.; Zhang, Pengfei; Turner, C. Heath; Cummings, Peter T.; Dai, Sheng

    2016-10-04

    Transport of electrolytes in nanoporous carbon-based electrodes largely defines the function and performance of energy storage devices. Here, using molecular dynamics simulation and quasielastic neutron scattering, we investigate the microscopic dynamics of a prototypical ionic liquid electrolyte, [emim][Tf2N], under applied electric potential in carbon materials with 6.7 nm and 1.5 nm pores. The simulations demonstrate the formation of dense layers of counter-ions near the charged surfaces, which is reversible when the polarity is reversed. In the experiment, the ions immobilized near the surface manifest themselves in the elastic scattering signal. The experimentally observed ion immobilization near the wall is fullymore » reversible as a function of the applied electric potential in the 6.7 nm, but not in the 1.5 nm nanopores. In the latter case, remarkably, the first application of the electric potential leads to apparently irreversible immobilization of cations or anions, depending on the polarity, near the carbon pore walls. This unexpectedly demonstrates that in carbon electrode materials with the small pores, which are optimal for energy storage applications, the polarity of the electrical potential applied for the first time after the introduction of an ionic liquid electrolyte may define the decoration of the small pore walls with ions for prolonged periods of time and possibly for the lifetime of the electrode.« less

  14. A Study of Second-Year Engineering Students' Alternative Conceptions about Electric Potential, Current Intensity and Ohm's Law

    ERIC Educational Resources Information Center

    Periago, M. Cristina; Bohigas, Xavier

    2005-01-01

    The aim of this research was to evaluate and analyse second-year industrial engineering and chemical engineering students prior knowledge of conceptual aspects of "circuit theory". Specifically, we focused on the basic concepts of electric potential and current intensity and on the fundamental relationship between them as expressed by Ohm's law.…

  15. A Study on Grid-Square Statistics Based Estimation of Regional Electricity Demand and Regional Potential Capacity of Distributed Generators

    NASA Astrophysics Data System (ADS)

    Kato, Takeyoshi; Sugimoto, Hiroyuki; Suzuoki, Yasuo

    We established a procedure for estimating regional electricity demand and regional potential capacity of distributed generators (DGs) by using a grid square statistics data set. A photovoltaic power system (PV system) for residential use and a co-generation system (CGS) for both residential and commercial use were taken into account. As an example, the result regarding Aichi prefecture was presented in this paper. The statistical data of the number of households by family-type and the number of employees by business category for about 4000 grid-square with 1km × 1km area was used to estimate the floor space or the electricity demand distribution. The rooftop area available for installing PV systems was also estimated with the grid-square statistics data set. Considering the relation between a capacity of existing CGS and a scale-index of building where CGS is installed, the potential capacity of CGS was estimated for three business categories, i.e. hotel, hospital, store. In some regions, the potential capacity of PV systems was estimated to be about 10,000kW/km2, which corresponds to the density of the existing area with intensive installation of PV systems. Finally, we discussed the ratio of regional potential capacity of DGs to regional maximum electricity demand for deducing the appropriate capacity of DGs in the model of future electricity distribution system.

  16. Non-contact measurement of electric potential of photovoltaic cells in a module and novel characterization technologies

    NASA Astrophysics Data System (ADS)

    Hishikawa, Yoshihiro; Yamagoe, Kengo; Onuma, Tsuyoshi

    2015-08-01

    A novel noncontact method of measuring the electric potential of component cells in photovoltaic (PV) modules is investigated using electrostatic field measurement technology. Experimental results for various kinds of PV cells and modules are presented, and their measurement principle as well as practical factors that affect the measurement results are discussed. It is demonstrated that the DC electric potential of the cells in various crystalline silicon and thin-film PV modules can be measured indoors through their cover glass or backsheet within a resolution of the output voltage of about 1 cell. The method is also applicable to the outdoor measurement of PV modules under grid-connected operation, and enables various kinds of characterization such as identifying low-performance cells in a PV module and degraded modules in a PV array, and determining the balance of their output current under outdoor operating conditions. Different distributions of electric potential measured from the front and back surfaces are observed for some types of modules. These differences are suggested, by the results of the analysis of experiments and numerical simulations, to originate from the modification of the module’s surface electric potential by slight current flow through its component materials such as the cover glass, ethylene vinyl acetate (EVA), and backsheet.

  17. Modeling the electric potential across neuronal membranes: the effect of fixed charges on spinal ganglion neurons and neuroblastoma cells.

    PubMed

    Pinto, Thiago M; Wedemann, Roseli S; Cortez, Célia M

    2014-01-01

    We present a model for the electric potential profile across the membranes of neuronal cells. We considered the resting and action potential states, and analyzed the influence of fixed charges of the membrane on its electric potential, based on experimental values of membrane properties of the spinal ganglion neuron and the neuroblastoma cell. The spinal ganglion neuron represents a healthy neuron, and the neuroblastoma cell, which is tumorous, represents a pathological neuron. We numerically solved the non-linear Poisson-Boltzmann equation for the regions of the membrane model we have adopted, by considering the densities of charges dissolved in an electrolytic solution and fixed on both glycocalyx and cytoplasmic proteins. Our model predicts that there is a difference in the behavior of the electric potential profiles of the two types of cells, in response to changes in charge concentrations in the membrane. Our results also describe an insensitivity of the neuroblastoma cell membrane, as observed in some biological experiments. This electrical property may be responsible for the low pharmacological response of the neuroblastoma to certain chemotherapeutic treatments. PMID:24801682

  18. Deregulation of the Electric Industry and Its Potential Benefits for School Districts.

    ERIC Educational Resources Information Center

    Watkiss, Jeffrey D.

    1997-01-01

    The electric utility industry is the last bastion of regulated monopolies in the United States. An overview of recent competition in the electric-power industry at both the federal and state levels and how this may affect school districts is offered in this article. The text identifies and evaluates how school districts can obtain cheaper power…

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

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

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

  20. Pollution prevention cost savings potential

    SciTech Connect

    Celeste, J.

    1994-12-01

    The waste generated by DOE facilities is a serious problem that significantly impacts current operations, increases future waste management costs, and creates future environmental liabilities. Pollution Prevention (P2) emphasizes source reduction through improved manufacturing and process control technologies. This concept must be incorporated into DOE`s overall operating philosophy and should be an integral part of Total Quality Management (TQM) program. P2 reduces the amount of waste generated, the cost of environmental compliance and future liabilities, waste treatment, and transportation and disposal costs. To be effective, P2 must contribute to the bottom fine in reducing the cost of work performed. P2 activities at LLNL include: researching and developing innovative manufacturing; evaluating new technologies, products, and chemistries; using alternative cleaning and sensor technologies; performing Pollution Prevention Opportunity Assessments (PPOAs); and developing outreach programs with small business. Examples of industrial outreach are: innovative electroplating operations, printed circuit board manufacturing, and painting operations. LLNL can provide the infrastructure and technical expertise to address a wide variety of industrial concerns.

  1. Saving Energy. Managing School Facilities, Guide 3.

    ERIC Educational Resources Information Center

    Department for Education and Employment, London (England). Architects and Building Branch.

    This guide offers information on how schools can implement an energy saving action plan to reduce their energy costs. Various low-cost energy-saving measures are recommended covering heating levels and heating systems, electricity demand reduction and lighting, ventilation, hot water usage, and swimming pool energy management. Additional…

  2. Streamlined energy-savings calculations for heat-island reduction strategies

    SciTech Connect

    Akbari, Hashem; Konopacki, Steven J.

    2003-03-15

    We have developed summary tables (sorted by heating- and cooling-degree-days) to estimate the potential of Heat-Island Reduction (HIR) strategies (i.e., solar-reflective roofs, shade trees, reflective pavements, and urban vegetation) to reduce cooling-energy use in buildings. The tables provide estimates of savings for both direct effect (reducing heat gain through the building shell) and indirect effect (reducing the ambient air temperature). In this analysis, we considered three building types that offer the most savings potential : residences, offices, and retail stores. Each building type was characterized in detail by Pre-1980 (old) or 1980+ (new) construction vintage and with natural gas or electricity as heating fuel. We defined prototypical-building characteristics for each building type and simulated the effects of HIR strategies on building cooling and heating energy use and peak power demand using the DOE-2.1E model and weather data for about 240 locations in the U.S. A statistical analysis of previously completed simulations for five cities was used to estimate the indirect savings. Our simulations included the effect of (1) solar-reflective roofing material on building [direct effect], (2) placement of deciduous shade trees near south and west walls of building [direct effect], and (3) ambient cooling achieved by urban reforestation and reflective building surfaces and pavements [indirect effect]. Upon completion of estimating the direct and indirect energy savings for all the selected locations, we integrated the results in tables arranged by heating- and cooling-degree-days. We considered 15 bins for heating-degree-days, and 11 bins for cooling-degree-days. Energy use and savings are presented per 1000 ft2 of roof area. In residences heated with gas and in climates with greater than 1000 cooling-degree-days, the annual electricity savings in Pre-1980 stock ranged from 650 to 1300 kWh/1000ft2; for 1980+ stock savings ranged 300 to 600 kWh/1000 ft2

  3. Analysis of Potential Energy Corridors Proposed by the Western Electricity Coordinating Council

    SciTech Connect

    Kuiper, James A.; Cantwell, Brian J.; Hlava, Kevin J.; Moore, H Robert; Orr, Andrew B.; Zvolanek, Emily A.

    2014-02-24

    This report, Analysis of Potential Energy Corridors Proposed by the Western Electricity Coordinating Council (WECC), was prepared by the Environmental Science Division of Argonne National Laboratory (Argonne). The intent of WECC’s work was to identify planning-level energy corridors that the Department of Energy (DOE) and its affiliates could study in greater detail. Argonne was tasked by DOE to analyze the WECC Proposed Energy Corridors in five topic areas for use in reviewing and revising existing corridors, as well as designating additional energy corridors in the 11 western states. In compliance with Section 368 of the Energy Policy Act of 2005 (EPAct), the Secretaries of Energy, Agriculture, and the Interior (Secretaries) published a Programmatic Environmental Impact Statement in 2008 to address the proposed designation of energy transport corridors on federal lands in the 11 western states. Subsequently, Records of Decision designating the corridors were issued in 2009 by the Bureau of Land Management (BLM) and the U.S. Forest Service (USFS). The 2012 settlement of a lawsuit, brought by The Wilderness Society and others against the United States, which identified environmental concerns for many of the corridors requires, among other things, periodic reviews of the corridors to assess the need for revisions, deletions, or additions. A 2013 Presidential Memorandum requires the Secretaries to undertake a continuing effort to identify and designate energy corridors. The WECC Proposed Energy Corridors and their analyses in this report provide key information for reviewing and revising existing corridors, as well as designating additional energy corridors in the 11 western states. Load centers and generation hubs identified in the WECC analysis, particularly as they reflect renewable energy development, would be useful in reviewing and potentially updating the designated Section 368 corridor network. Argonne used Geographic Information System (GIS) technology to

  4. Potassium Fluxes in Chlamydomonas reinhardtii (I.Kinetics and Electrical Potentials).

    PubMed Central

    Malhotra, B.; Glass, ADM.

    1995-01-01

    Potassium influx and cellular [K+] were measured in the unicellular green alga Chlamydomonas reinhardtii after pretreatment in either 10 or 0 mM external K+ ([K]0). K+ (42K+ or 86Rb+) influx was mediated by a saturable, high-affinity transport system (HATS) at low [K+]0 and a linear, low-affinity transport system at high [K+]o. The HATS was typically more sensitive to metabolic inhibition (and darkness) than the low-affinity transport system. Membrane electrical potentials were determined by measuring the equilibrium distribution of tetraphenylphosphonium. These values, together with estimates of cytoplasmic [K+] (B. Malhotra and A.D.M. Glass [1995] Plant Physiol 108: 1537-1545), demonstrated that at 0.1 mM [K+]0 K+ uptake must be active. At higher [K+]0 (>0.3 mM) K+ influx appeared to be passive and possibly channel mediated. When cells were deprived of K+ for 24 h, the Vmax for the HATS increased from 50 x 10-6 to 85 x 10-6 nmol h-1 cell-1 and the Km value decreased from 0.25 to 0.162 mM. Meanwhile, cellular [K+] declined from 24 x 10-6 to 9 x 10-6 nmol cell-1. During this period influx increased exponentially, reaching its peak value after 18 h of K+ deprivation. This increase of K+ influx was not expressed when cells were exposed to inhibitors of protein synthesis. The use of 42K+ and 86Rb+ in parallel experiments demonstrated that Chlamydomonas discriminated in favor of K+ over Rb+, and this effect increased with the duration of K+ deprivation. PMID:12228559

  5. Wall System Saves Initial HVAC Costs

    ERIC Educational Resources Information Center

    Modern Schools, 1976

    1976-01-01

    The superior insulating characteristics of an exterior wall system has enabled a Massachusetts school district to realize a savings on electric heating, ventilating, and air-conditioning systems. (Author/MLF)

  6. Observation of pressure stimulated voltages in rocks using an electric potential sensor

    SciTech Connect

    Aydin, A.; Prance, R. J.; Prance, H.; Harland, C. J.

    2009-09-21

    Recent interest in the electrical activity in rock and the use of electric field transients as candidates for earthquake precursors has led to studies of pressure stimulated currents in laboratory samples. In this paper, an electric field sensor is used to measure directly the voltages associated with these currents. Stress was applied as uniaxial compression to marble and granite at an approximately constant rate. In contrast with the small pressure stimulated currents previously measured, large voltage signals are reported. Polarity reversal of the signal was observed immediately before fracture for the marble, in agreement with previous pressure stimulated current studies.

  7. Cortical Dendritic Spine Heads Are Not Electrically Isolated by the Spine Neck from Membrane Potential Signals in Parent Dendrites

    PubMed Central

    Popovic, Marko A.; Gao, Xin; Carnevale, Nicholas T.; Zecevic, Dejan

    2014-01-01

    The evidence for an important hypothesis that cortical spine morphology might participate in modifying synaptic efficacy that underlies plasticity and possibly learning and memory mechanisms is inconclusive. Both theory and experiments suggest that the transfer of excitatory postsynaptic potential signals from spines to parent dendrites depends on the spine neck morphology and resistance. Furthermore, modeling of signal transfer in the opposite direction predicts that synapses on spine heads are not electrically isolated from voltages in the parent dendrite. In sharp contrast to this theoretical prediction, one of a very few measurements of electrical signals from spines reported that slow hyperpolarizing membrane potential changes are attenuated considerably by the spine neck as they spread from dendrites to synapses on spine heads. This result challenges our understanding of the electrical behavior of spines at a fundamental level. To re-examine the specific question of the transfer of dendritic signals to synapses of spines, we took advantage of a high-sensitivity Vm-imaging technique and carried out optical measurements of electrical signals from 4 groups of spines with different neck length and simultaneously from parent dendrites. The results show that spine neck does not filter membrane potential signals as they spread from the dendrites into the spine heads. PMID:23054810

  8. Synthesis, electrical and thermal conductivities, and potential applications of graphite fluoride fibers

    NASA Technical Reports Server (NTRS)

    Hung, Ching-Cheh; Long, Martin; Stahl, Mark

    1988-01-01

    Graphite fluoride fibers can be produced by fluorinating pristine or intercalated graphite fibers. The higher the degree of graphitization of the fibers, the higher the temperature needed to reach the same degree of fluorination. Structural damage during high temperature fluorination can be reduced or eliminated by pretreating the fibers with bromine and/or fluorine. The electrical resistivity of the fibers was in the 0.01 to 10 to the 11th ohm-cm range. The thermal conductivity of these fibers ranged from 5 to 75 W/m-K, which is much larger than the thermal conductivity of glass (1.1 W/m-K), the commonly used fiber in epoxy composites. A composite made from graphite fluoride fibers and epoxy or PTFE may be highly thermally conducting and electrically insulating or semiconducting. The electrically insulating product may be used as heat sinks for electrical or electronic instruments.

  9. Streaming potential for microchannels of arbitrary cross-sectional shapes for thin electric double layers.

    PubMed

    Park, H M; Lim, J Y

    2009-08-15

    The streaming potential of electrokinetic flows in microchannels affects flow rate and is usually exploited to determine the zeta potential of microchannels. In the present investigation, we derive a semianalytic formula for the streaming potential of microchannels with arbitrary cross-sectional shapes valid for high zeta potentials as well as reasonably low zeta potentials. This formula satisfies the Onsager reciprocity principle at the limit of low zeta potential where the Debye-Hückel approximation is valid. The simple semianalytic formula for the streaming potential derived in the present work can be employed to investigate electrokinetic flows and determine the zeta potentials of microchannels with arbitrary cross-sectional shapes. PMID:19464020

  10. The potential impacts of electric vehicles on air quality in the urban areas of Barcelona and Madrid (Spain)

    NASA Astrophysics Data System (ADS)

    Soret, A.; Guevara, M.; Baldasano, J. M.

    2014-12-01

    This work analyses the potential air quality improvements resulting from three fleet electrification scenarios (∼13, 26 and 40%) by replacing conventional vehicles with Electric Battery Vehicles (EBVs), Plug-in Hybrid Electric Vehicles (PHEVs) and Hybrid Electric Vehicles (HEVs). This study has been performed for the cities of Barcelona and Madrid (Spain), where road transport is the primary emission source. In these urban areas, several air quality problems are present, mainly related to NO2 and particulate matter. The WRF-ARW/HERMESv2/CMAQ model system has been applied at high spatial (1 × 1 km2) and temporal (1 h) resolution. The results show that fleet electrification offers a potential for emission abatement, especially related to NOx and CO. Regarding the more ambitious scenario (∼40% fleet electrification), reductions of 11% and 17% of the total NOx emissions are observed in Barcelona and Madrid respectively. These emissions reductions involve air quality improvements in NO2 maximum hourly values up to 16%: reductions up to 30 and 35 μg m-3 in Barcelona and Madrid, respectively. Furthermore, an additional scenario has been defined considering electric generation emissions associated with EBVs and PHEVs charging from a combined-cycle power plant. These charging emissions would produce slight NO2 increases in the downwind areas of <3 μg m-3. Thus, fleet electrification would improve urban air quality even when considering emissions associated with charging electric vehicles. However, two further points should be considered. First, fleet electrification cannot be considered a unique solution, and other management strategies may be defined. This is especially important with respect to particulate matter emissions, which are not significantly reduced by fleet electrification (<5%) due to the high weight of non-exhaust emissions. Second, a significant introduction of electric vehicles (26-40%) involving all vehicle categories is required to improve urban

  11. Opioids potentiate electrical transmission at mixed synapses on the Mauthner cell

    PubMed Central

    Cachope, Roger

    2015-01-01

    Opioid receptors were shown to modulate a variety of cellular processes in the vertebrate central nervous system, including synaptic transmission. While the effects of opioid receptors on chemically mediated transmission have been extensively investigated, little is known of their actions on gap junction-mediated electrical synapses. Here we report that pharmacological activation of mu-opioid receptors led to a long-term enhancement of electrical (and glutamatergic) transmission at identifiable mixed synapses on the goldfish Mauthner cells. The effect also required activation of both dopamine D1/5 receptors and postsynaptic cAMP-dependent protein kinase A, suggesting that opioid-evoked actions are mediated indirectly via the release of dopamine from varicosities known to be located in the vicinity of the synaptic contacts. Moreover, inhibitory inputs situated in the immediate vicinity of these excitatory synapses on the lateral dendrite of the Mauthner cell were not affected by activation of mu-opioid receptors, indicating that their actions are restricted to electrical and glutamatergic transmissions co-existing at mixed contacts. Thus, as their chemical counterparts, electrical synapses can be a target for the modulatory actions of the opioid system. Because gap junctions at these mixed synapses are formed by fish homologs of the neuronal connexin 36, which is widespread in mammalian brain, it is likely that this regulatory property applies to electrical synapses elsewhere as well. PMID:26019311

  12. Estimate of Cost-Effective Potential for Minimum Efficiency Performance Standards in 13 Major World Economies Energy Savings, Environmental and Financial Impacts

    SciTech Connect

    Letschert, Virginie E.; Bojda, Nicholas; Ke, Jing; McNeil, Michael A.

    2012-07-01

    This study analyzes the financial impacts on consumers of minimum efficiency performance standards (MEPS) for appliances that could be implemented in 13 major economies around the world. We use the Bottom-Up Energy Analysis System (BUENAS), developed at Lawrence Berkeley National Laboratory (LBNL), to analyze various appliance efficiency target levels to estimate the net present value (NPV) of policies designed to provide maximum energy savings while not penalizing consumers financially. These policies constitute what we call the “cost-effective potential” (CEP) scenario. The CEP scenario is designed to answer the question: How high can we raise the efficiency bar in mandatory programs while still saving consumers money?

  13. Bulk meltwater flow and liquid water content of snowpacks mapped using the electrical self-potential (SP) method

    NASA Astrophysics Data System (ADS)

    Thompson, Sarah S.; Kulessa, Bernd; Essery, Richard L. H.; Lüthi, Martin P.

    2016-02-01

    Our ability to measure, quantify and assimilate hydrological properties and processes of snow in operational models is disproportionally poor compared to the significance of seasonal snowmelt as a global water resource and major risk factor in flood and avalanche forecasting. We show here that strong electrical self-potential fields are generated in melting in situ snowpacks at Rhone Glacier and Jungfraujoch Glacier, Switzerland. In agreement with theory, the diurnal evolution of self-potential magnitudes ( ˜ 60-250 mV) relates to those of bulk meltwater fluxes (0-1.2 × 10-6 m3 s-1) principally through the permeability and the content, electrical conductivity and pH of liquid water. Previous work revealed that when fresh snow melts, ions are eluted in sequence and electrical conductivity, pH and self-potential data change diagnostically. Our snowpacks had experienced earlier stages of melt, and complementary snow pit measurements revealed that electrical conductivity ( ˜ 1-5 × 10-6 S m-1) and pH ( ˜ 6.5-6.7) as well as permeabilities (respectively ˜ 9.7 × 10-5 and ˜ 4.3 × 10-5 m2 at Rhone Glacier and Jungfraujoch Glacier) were invariant. This implies, first, that preferential elution of ions was complete and, second, that our self-potential measurements reflect daily changes in liquid water contents. These were calculated to increase within the pendular regime from ˜ 1 to 5 and ˜ 3 to 5.5 % respectively at Rhone Glacier and Jungfraujoch Glacier, as confirmed by ground truth measurements. We conclude that the electrical self-potential method is a promising snow and firn hydrology sensor owing to its suitability for (1) sensing lateral and vertical liquid water flows directly and minimally invasively, (2) complementing established observational programs through multidimensional spatial mapping of meltwater fluxes or liquid water content and (3) monitoring autonomously at a low cost. Future work should focus on the development of self-potential sensor

  14. Mutagenic and genotoxic potential of direct electric current in Escherichia coli and Salmonella thyphimurium strains.

    PubMed

    Gomes, Marina das Neves; Cardoso, Janine Simas; Leitão, Alvaro Costa; Quaresma, Carla Holandino

    2016-05-01

    Direct electric current has several therapeutic uses such as antibacterial and antiprotozoal action, tissues scarring and regeneration, as well as tumor treatment. This method has shown promising results in vivo and in vitro, with significant efficacy and almost no side effects. Considering lack of studies regarding direct electric current mutagenic and/or genotoxic effects, the present work evaluated both aspects by using five different bacterial experimental assays: survival of repair-deficient mutants, Salmonella-histidine reversion mutagenesis (Ames test), forward mutations to rifampicin resistance, phage reactivation, and lysogenic induction. In these experimental conditions, cells were submitted to an approach that allows evaluation of anodic, cathodic, and electro-ionic effects generated by 2 mA of direct electric current, with doses ranging from 0.36 to 3.60 Coulombs. Our results showed these doses did not induce mutagenic or genotoxic effects.

  15. Formation of photoluminescent n-type macroporous silicon: Effect of magnetic field and lateral electric potential

    NASA Astrophysics Data System (ADS)

    Antunez, E. E.; Estevez, J. O.; Campos, J.; Basurto-Pensado, M. A.; Agarwal, V.

    2014-11-01

    Metal electrode-free electrochemical etching of low doped n-type silicon substrates, under the combined effect of magnetic and lateral electric field, is used to fabricate photoluminescent n-type porous silicon structures in dark conditions. A lateral gradient in terms of structural characteristics (i.e. thickness and pore dimensions) along the electric field direction is formed. Enhancement of electric and magnetic field resulted in the increase of pore density and a change in the shape of the macropore structure, from circular to square morphology. Broad photoluminescence (PL) emission from 500 to 800 nm, with a PL peak wavelength ranging from 571 to 642 nm, is attributed to the wide range of microporous features present on the porous silicon layer.

  16. Save Energy $.

    ERIC Educational Resources Information Center

    Hirsch, Thomas E., III; Shapiro, Robert F.

    1986-01-01

    Large institutional energy users can reduce energy costs by constructing and operating steam and electricity cogeneration facilities and purchasing their own gas at lower prices rather than relying on local distributors. (MSE)

  17. Bose-Einstein condensates in strong electric fields: Effective gauge potentials and rotating states

    SciTech Connect

    Kailasvuori, J.M.; Hansson, T.H.; Kavoulakis, G.M.

    2002-11-01

    Magnetically trapped atoms in Bose-Einstein condensates are spin polarized. Since the magnetic field is inhomogeneous, the atoms acquire Berry phases of the Aharonov-Bohm type during adiabatic motion. In the presence of an electric field, there is an additional Aharonov-Casher effect. Taking into account the limitations on the strength of the electric fields due to the polarizability of the atoms, we investigate the extent to which these effects can be used to induce rotation in a Bose-Einstein condensate.

  18. Efficient calculation of the quasi-static electrical potential on a tetrahedral mesh and its implementation in STEPS

    PubMed Central

    Hepburn, Iain; Cannon, Robert; De Schutter, Erik

    2013-01-01

    We describe a novel method for calculating the quasi-static electrical potential on tetrahedral meshes, which we call E-Field. The E-Field method is implemented in STEPS, which performs stochastic spatial reaction-diffusion computations in tetrahedral-based cellular geometry reconstructions. This provides a level of integration between electrical excitability and spatial molecular dynamics in realistic cellular morphology not previously achievable. Deterministic solutions are also possible. By performing the Rallpack tests we demonstrate the accuracy of the E-Field method. Efficient node ordering is an important practical consideration, and we find that a breadth-first search provides the best solutions, although principal axis ordering suffices for some geometries. We discuss potential applications and possible future directions, and predict that the E-Field implementation in STEPS will play an important role in the future of multiscale neural simulations. PMID:24194715

  19. A compact electric potential sensor array for the acquisition and reconstruction of the 7-lead electrocardiogram without electrical charge contact with the skin.

    PubMed

    Harland, C J; Clark, T D; Peters, N S; Everitt, M J; Stiffell, P B

    2005-12-01

    Conventional electrocardiogram (ECG) systems make use of separate electrical connections to the arms and legs. These use a 'long baseline' for the voltage reference potential which in the case of precordial ECG leads is provided using a Wilson central terminal (WCT) wiring configuration. The aims of this project were (a) to construct compact, non-invasive surface ECG sensor arrays which would operate without the need for a WCT reference, (b) to obtain high quality precordial ECGs showing fine differences in ECG detail between small adjacent areas of the chest and (c) to reconstruct, from a compact array of four sensors, ECGs which closely match to the conventional 7-lead ECG system, but without the need for multiple wires and long baselines. In this paper, we describe two sensor array configurations which have been constructed using electric potential sensors (EPSs). We show high quality precordial ECGs obtained from small areas of the surface of the chest and show the different angular vectors (leads) in the frontal cardiac plane constructed using signals from the array elements. We suggest that these ECG arrays, which are simple to apply, should prove to be a valuable tool in providing useful information about the state of the heart. PMID:16311443

  20. Growth patterns of dendrimers and electric potential oscillations during electropolymerization of pyrrole using mono- and mixed surfactants.

    PubMed

    Das, Ishwar; Goel, Neha; Agrawal, Namita R; Gupta, Sanjeev Kumar

    2010-10-14

    Fractal and dendrimer growth patterns of polypyrrole were obtained during electrochemical polymerization of pyrrole in systems (A) pyrrole-sodium dodecyl sulfate (NaDS)-water and (B) pyrrole-NaDS-cetyl trimethyl ammonium bromide (CTAB)-water. Different morphological transitions including compact → flower-like and fractal → dendrimer → fractal were observed depending on experimental conditions. Growth kinetics during electropolymerization of pyrrole was studied. Growth rate was found to be higher in system A than in B. Effect of [NaDS], [pyrrole], and field intensity on morphology and weight of polymer aggregates was also studied in both the systems. Different empirical equations were obeyed under different conditions. Electropolymerized aggregates were characterized by transmission electron microscopy (TEM), powder X-ray diffraction (XRD), electrical conductivity measurement, and reflectance spectroscopy. TEM studies revealed that the particle size decreased to ∼140-200 nm in the presence of CTAB. The decrease in particle size on addition of CTAB was also observed in XRD studies. Reflectance spectra of the polymer aggregates support the large π-conjugation in the dendrimer. During electropolymerization, oscillations in potential were monitored as a function of time. Results indicated that growth pattern and electric potential oscillations were interrelated. In the case of fractal growth, the amplitude of chaotic oscillation was higher than the amplitude of oscillation during the growth of dendrimer. Growth morphologies and electric potential oscillations have been explained on the basis of modified Diaz's mechanism.

  1. The 2H electric dipole moment in a separable potential approach

    SciTech Connect

    Gibson, Benjamin; Afnan, I. R.

    2009-01-01

    Measurement of the electric dipole moment of H or HE may well come prior to the coveted measurement of the neutron EDM. Exact model calculations for the deuteron are feasible, and we explore here the model dependence of such deuteron EDM calculations.

  2. Effect of pulsed electric field treatment on hot-boned muscles of different potential tenderness.

    PubMed

    Suwandy, Via; Carne, Alan; van de Ven, Remy; Bekhit, Alaa El-Din A; Hopkins, David L

    2015-07-01

    In this study, the effect of pulsed electric field (PEF) treatment and ageing on the quality of beef M. longissimus lumborum (LL) and M. semimembranosus (SM) muscles was evaluated, including the tenderness, water loss and post-mortem proteolysis. Muscles were obtained from 12 steers (6 steers for each muscle), removed from the carcasses 4 hour postmortem and were treated with pulsed electric field within 2h. Six different pulsed electric field intensities (voltages of 5 and 10 kV × frequencies of 20, 50 and 90 Hz) plus a control were applied to each muscle to determine the optimum treatment conditions. Beef LL was found to get tougher with increasing treatment frequency whereas beef SM muscle was found to have up to 21.6% reduction in the shear force with pulsed electric field treatment. Post-mortem proteolysis showed an increase in both troponin and desmin degradation in beef LL treated with low intensity PEF treatment (20 Hz) compared to non-treated control samples.

  3. Effect of pulsed electric field treatment on hot-boned muscles of different potential tenderness.

    PubMed

    Suwandy, Via; Carne, Alan; van de Ven, Remy; Bekhit, Alaa El-Din A; Hopkins, David L

    2015-07-01

    In this study, the effect of pulsed electric field (PEF) treatment and ageing on the quality of beef M. longissimus lumborum (LL) and M. semimembranosus (SM) muscles was evaluated, including the tenderness, water loss and post-mortem proteolysis. Muscles were obtained from 12 steers (6 steers for each muscle), removed from the carcasses 4 hour postmortem and were treated with pulsed electric field within 2h. Six different pulsed electric field intensities (voltages of 5 and 10 kV × frequencies of 20, 50 and 90 Hz) plus a control were applied to each muscle to determine the optimum treatment conditions. Beef LL was found to get tougher with increasing treatment frequency whereas beef SM muscle was found to have up to 21.6% reduction in the shear force with pulsed electric field treatment. Post-mortem proteolysis showed an increase in both troponin and desmin degradation in beef LL treated with low intensity PEF treatment (20 Hz) compared to non-treated control samples. PMID:25754097

  4. Effect of tax, financing, and operating-cost incentives on retiree homeowners' current and potential decisions to purchase energy-saving improvements

    SciTech Connect

    Long, A.W. Jr.

    1983-01-01

    This study focused on retiree homeowners to determine their level of participation, causes of non-participation and the effect of selected incentive modifications on investment decisions. A descriptive-elemental approach was taken to explore three research questions. Fifty semi-structured interviews selected through restricted probability were conducted in Sun City, California. Findings were keyed to sex, age, education and income and statistically analyzed using the chi-square test. Retiree homeowners had coped with rising utility costs through modified usage practice rather than through energy-saving investments. Concerns over access to funding, required initial payout, return on investment, future prices of energy and risk were highest among those of least education or income. A desire to retain an existing life style was important to those of higher education and income. Level of awareness of incentive features was also a major decision factor. The analysis indicated that energy-saving investments will increase if retiree homeowners are offered shared-cost obligation by the individual, government, and utility; exemption from sales tax for all energy-saving-item sales and service; state tax exemption for federal tax credits; exemption of energy-saving improvements from property tax; continued federal tax credit; investment loans sufficiently available to meet demand; energy-producing equipment available for rent or lease at reasonable rates.

  5. Real-Space Distributions of Electrical Potential in Planar and Porous Peroveskite Solar Cells: Carrier Separation and Transport

    SciTech Connect

    Jiang, Chun-Sheng; Yang, Mengjin; Zhou, Yuanyuan; To, Bobby; Nanayakkara, Sanjini; Luther, Joseph; Zhou, Weilie; Berry, Joseph J.; Van de Lagemaat, Jao; Padture, Nitin P.; Zhu, Kai; Al-Jassim, Mowafak M.

    2015-06-14

    We study the carrier transport and separation in planar and porous PS devices, which is one of the most fundamental operation mechanisms of solar cells, by profiling the electrical potential across the devices. We found that the PV devices work by p-n junction at the TiO2/PS interface for the both device structures. Combining the potential profiling results with the solar cell performance parameters taken on the optimized and thickened devices, we found that mobility is the main factor limiting the device performance. Improving the mobility both within grains and across grain boundaries (or enlarging the grain size) are expected to significantly improve the device efficiency.

  6. Observation of electric potential in organic thin-film transistor by bias-applied hard X-ray photoemission spectroscopy

    NASA Astrophysics Data System (ADS)

    Watanabe, Takeshi; Tada, Keisuke; Yasuno, Satoshi; Oji, Hiroshi; Yoshimoto, Noriyuki; Hirosawa, Ichiro

    2016-03-01

    The effect of gate voltage on electric potential in a pentacene (PEN) layer was studied by hard X-ray photoelectron spectroscopy under a bias voltage. It was observed that applying a negative gate voltage substantially increases the width of a C 1s peak. This suggested that injected and accumulated carriers in an organic thin film transistor channel modified the potential depth profile in PEN. It was also observed that the C 1s kinetic energy tends to increase monotonically with threshold voltage.

  7. Determining electrically evoked compound action potential thresholds: A comparison of computer versus human analysis methods

    PubMed Central

    Glassman, E. Katelyn; Hughes, Michelle L.

    2012-01-01

    Objectives Current cochlear implants (CIs) have telemetry capabilities for measuring the electrically evoked compound action potential (ECAP). Neural Response Telemetry (NRT™; Cochlear) and Neural Response Imaging (NRI; Advanced Bionics [AB]) can measure ECAP responses across a range of stimulus levels to obtain an amplitude growth function. Software-specific algorithms automatically mark the leading negative peak, N1, and the following positive peak/plateau, P2, and apply linear regression to estimate ECAP threshold. Alternatively, clinicians may apply expert judgments to modify the peak markers placed by the software algorithms, and/or use visual detection to identify the lowest level yielding a measurable ECAP response. The goals of this study were to: (1) assess the variability between human and computer decisions for (a) marking N1 and P2, and (b) determination of linear regression threshold (LRT) and visual detection threshold (VDT); and (2) compare LRT and VDT methods within and across human and computer decision methods. Design ECAP amplitude growth functions were measured for three electrodes in each of 20 ears (10 Cochlear Nucleus® 24RE/CI512, and 10 AB CII/90K). LRT, defined as the current level yielding an ECAP with zero amplitude, was calculated for both computer- (C-LRT) and human-picked peaks (H-LRT). VDT, defined as the lowest level resulting in a measurable ECAP response, was also calculated for both computer- (C-VDT) and human-picked peaks (H-VDT). Because NRI assigns peak markers to all waveforms but does not include waveforms with amplitudes less than 20 μV in its regression calculation, C-VDT for AB subjects was defined as the lowest current level yielding an amplitude ≥20 μV. Results Overall, there were significant correlations between human and computer decisions for peak-marker placement, LRT, and VDT for both manufacturers (r = 0.78 to 1.00, p < 0.001). For Cochlear devices, LRT and VDT correlated equally well for both computer- and

  8. Unmasking local activity within local field potentials (LFPs) by removing distal electrical signals using independent component analysis

    PubMed Central

    Whitmore, Nathan W.; Lin, Shih-Chieh

    2016-01-01

    Local field potentials (LFPs) are commonly thought to reflect the aggregate dynamics in local neural circuits around recording electrodes. However, we show that when LFPs are recorded in awake behaving animals against a distal reference on the skull as commonly practiced, LFPs are significantly contaminated by non-local and non-neural sources arising from the reference electrode and from movement-related noise. In a data set with simultaneously recorded LFPs and electroencephalograms (EEGs) across multiple brain regions while rats perform an auditory oddball task, we used independent component analysis (ICA) to identify signals arising from electrical reference and from volume-conducted noise based on their distributed spatial pattern across multiple electrodes and distinct power spectral features. These sources of distal electrical signals collectively accounted for 23–77% of total variance in unprocessed LFPs, as well as most of the gamma oscillation responses to the target stimulus in EEGs. Gamma oscillation power was concentrated in volume-conducted noise and was tightly coupled with the onset of licking behavior, suggesting a likely origin of muscle activity associated with body movement or orofacial movement. The removal of distal signal contamination also selectively reduced correlations of LFP/EEG signals between distant brain regions but not within the same region. Finally, the removal of contamination from distal electrical signals preserved an event-related potential (ERP) response to auditory stimuli in the frontal cortex and also increased the coupling between the frontal ERP amplitude and neuronal activity in the basal forebrain, supporting the conclusion that removing distal electrical signals unmasked local activity within LFPs. Together, these results highlight the significant contamination of LFPs by distal electrical signals and caution against the straightforward interpretation of unprocessed LFPs. Our results provide a principled approach to

  9. Improving High School Students' Understanding of Potential Difference in Simple Electric Circuits

    ERIC Educational Resources Information Center

    Liegeois, Laurent; Chasseigne, G'erard; Papin, Sophie; Mullet, Etienne

    2003-01-01

    This paper reports two studies into the understanding of the concept of potential difference in the current-potential difference-resistance context among 8th-12th graders (Study 1), and the efficiency of a learning device derived from Social Judgment Theory (Study 2). These two studies showed that: (a) when asked to infer potential difference from…

  10. Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings

    SciTech Connect

    Garbesi, Karina; Vossos, Vagelis; Sanstad, Alan; Burch, Gabriel

    2011-10-13

    An increasing number of energy efficient appliances operate on direct current (DC) internally, offering the potential to use DC from renewable energy systems directly and avoiding the losses inherent in converting power to alternating current (AC) and back. This paper investigates that potential for net-metered residences with on-site photovoltaics (PV) by modeling the net power draw of the ‘direct-DC house’ with respect to today’s typical configuration, assuming identical DC-internal loads. Power draws were modeled for houses in 14 U.S. cities, using hourly, simulated PV-system output and residential loads. The latter were adjusted to reflect a 33% load reduction, representative of the most efficient DC-internal technology, based on an analysis of 32 electricity end-uses. The model tested the effect of climate, electric vehicle (EV) loads, electricity storage, and load shifting on electricity savings; a sensitivity analysis was conducted to determine how future changes in the efficiencies of power system components might affect savings potential. Based on this work, we estimate that net-metered PV residences could save 5% of their total electricity load for houses without storage and 14% for houses with storage. Based on residential PV penetration projections for year 2035 obtained from the National Energy Modeling System (2.7% for the reference case and 11.2% for the extended policy case), direct-DC could save the nation 10 trillion Btu (without storage) or 40 trillion Btu (with storage). Shifting the cooling load by two hours earlier in the day (pre-cooling) has negligible benefits for energy savings. Direct-DC provides no energy savings benefits for EV charging, to the extent that charging occurs at night. However, if charging occurred during the day, for example with employees charging while at work, the benefits would be large. Direct-DC energy savings are sensitive to power system and appliance conversion efficiencies but are not significantly

  11. The Potential For Energy Efficiency In The State of Iowa

    SciTech Connect

    Hadley, SW

    2001-12-05

    . The study did not involve changes to the building shell (e.g., increased insulation) or residential lighting improvements. Nevertheless, the residential sector's market potential for electrical energy savings was calculated to be 5.3% of expected electrical use, representing 850 GWh by 2020. Natural gas savings could be 2.4% of expected gas use, representing 2.1 trillion Btus. Using expected prices for energy in that year, these represent savings of $47 million and $12 million per year. In the commercial sector, the study only considered voluntary market-based policies for some of the technologies. The most notable savings were in ventilation (12% savings by 2020), lighting (12% savings), refrigeration (7% savings), water heating (6% savings), and space heating (5% savings by 2020). The commercial sector's market potential for electrical energy savings based on the programs modeled was calculated to be 5.1% of its total expected electrical use, representing 605 GWh of power by 2020. Natural gas savings were 2.3 trillion Btu, 3.7% of use. Using the same prices as the residential sector (5.5{cents}/kWh and $5.74/MBtu), the savings represent $33 million and $13 million per year, respectively.

  12. Supermarket refrigeration assessment for the Commonwealth Electric Company

    SciTech Connect

    Tsaros, T.L.; Walker, D.H. )

    1991-07-01

    The Commonwealth Electric Company (COM/Electric) has initiated an incentive program to promote electric energy conservation within its service territory. The Electric Power Research Institute (EPRI) has assisted COM/Electric in assessing the impact on the utility and its customers of implementing energy efficient supermarket refrigeration in retrofit applications. The primary task of this assessment was to contact the supermarket chains and refrigeration contractors and suppliers in the COM/Electric service territory to determine the type of refrigeration employed and standard or novel retrofit equipment implemented in supermarkets. With this information, estimates were made of the potential energy savings that COM/Electric and the supermarkets could realize if supermarkets were retrofitted with energy efficient refrigeration equipment. It was determined that the refrigerated display case features offering the greatest potential for savings through retrofit installations include doors for medium temperature multideck cases, high-efficiency fan motors, anti-sweat heater controls, and vinyl strip curtains for walk-in coolers. The retrofit components associated with the compressor machine room that offer the greatest potential for savings include the use of low heat pressure control, hot gas defrost, and external liquid-suction heat exchangers and remote evaporative subcoolers for low temperature refrigeration. 6 refs., 14 figs., 26 tabs.

  13. Electric industry restructuring, ancillary services, and the potential impact on wind

    SciTech Connect

    Kirby, B.; Hirst, E.; Parsons, B.; Porter, K.

    1997-12-31

    The new competitive electric power environment raises increased challenges for wind power. The DOE and EPRI wind programs have dealt extensively with the traditional vertically integrated utility planning and operating environment in which the host utility owns the generation (or purchases the power) and provides dispatch and transmission services. Under this traditional environment, 1794 MW of wind power, principally in California, have been successfully integrated into the U.S. electric power system. Another 4200 MW are installed elsewhere in the world. As issues have arisen, such as intermittency and voltage regulation, they have been successfully addressed with accepted power system procedures and practices. For an intermittent, non-dispatchable resource such as wind, new regulatory rules affecting power transmission services, raise questions about which ancillary services wind plants will be able to sell, which they will be required to purchase, and what the economic impacts will be on individual wind projects. This paper begins to look at issues of concern to wind in a restructured electric industry. The paper first briefly looks at the range of unbundled services and comments on their unique significance to wind. To illustrate the concerns that arise with restructuring, the paper then takes a more detailed look at a single service: regulation. Finally, the paper takes a brief look at technologies and strategies that could improve the competitive position of wind.

  14. A model for estimation of potential generation of waste electrical and electronic equipment in Brazil.

    PubMed

    Araújo, Marcelo Guimarães; Magrini, Alessandra; Mahler, Cláudio Fernando; Bilitewski, Bernd

    2012-02-01

    Sales of electrical and electronic equipment are increasing dramatically in developing countries. Usually, there are no reliable data about quantities of the waste generated. A new law for solid waste management was enacted in Brazil in 2010, and the infrastructure to treat this waste must be planned, considering the volumes of the different types of electrical and electronic equipment generated. This paper reviews the literature regarding estimation of waste electrical and electronic equipment (WEEE), focusing on developing countries, particularly in Latin America. It briefly describes the current WEEE system in Brazil and presents an updated estimate of generation of WEEE. Considering the limited available data in Brazil, a model for WEEE generation estimation is proposed in which different methods are used for mature and non-mature market products. The results showed that the most important variable is the equipment lifetime, which requires a thorough understanding of consumer behavior to estimate. Since Brazil is a rapidly expanding market, the "boom" in waste generation is still to come. In the near future, better data will provide more reliable estimation of waste generation and a clearer interpretation of the lifetime variable throughout the years.

  15. Nerve Growth Factor-Immobilized Electrically Conducting Fibrous Scaffolds for Potential Use in Neural Engineering Applications

    PubMed Central

    Lee, Jae Y.; Bashur, Chris A.; Milroy, Craig A.; Forciniti, Leandro; Goldstein, Aaron S.

    2015-01-01

    Engineered scaffolds simultaneously exhibiting multiple cues are highly desirable for neural tissue regeneration. To this end, we developed a neural tissue engineering scaffold that displays submicrometer-scale features, electrical conductivity, and neurotrophic activity. Specifically, electrospun poly(lactic acid-co-glycolic acid) (PLGA) nanofibers were layered with a nanometer thick coating of electrically conducting polypyrrole (PPy) presenting carboxylic groups. Then, nerve growth factor (NGF) was chemically immobilized onto the surface of the fibers. These NGF-immobilized PPy-coated PLGA (NGF-PPyPLGA) fibers supported PC12 neurite formation (28.0±3.0% of the cells) and neurite outgrowth (14.2 µm median length), which were comparable to that observed with NGF (50 ng/mL) in culture medium (29.0±1.3%, 14.4 µm). Electrical stimulation of PC12 cells on NGF-immobilized PPyPLGA fiber scaffolds was found to further improve neurite development and neurite length by 18% and 17%, respectively, compared to unstimulated cells on the NGF-immobilized fibers. Hence, submicrometer-scale fibrous scaffolds that incorporate neurotrophic and electroconducting activities may serve as promising neural tissue engineering scaffolds such as nerve guidance conduits. PMID:21712166

  16. Electric Potential Near The Extraction Region In Negative Ion Sources With Surface Produced Negative Ions

    SciTech Connect

    Fukano, A.; Hatayama, A.

    2011-09-26

    The potential distribution near the extraction region in negative ion sources for the plasma with the surface produced negative ions is studied analytically. The potential is derived analytically by using a plasma-sheath equation, where negative ions produced on the Plasma Grid (PG) surface are considered in addition to positive ions and electrons. A negative potential peak is formed in the sheath region near the PG surface for the case of strong surface production of negative ions or for low energy negative ions. Negative ions are reflected by the negative potential peak near the PG and returned to the PG surface. This reflection mechanism by the negative potential peak possibly becomes a factor in negative ion extraction. It is also indicated that the potential difference between the plasma region and the wall decreases by the surface produced negative ions. This also has the possibility to contribute to the negative ion extraction.

  17. Spatial distribution of the electrical potential and ion concentration in the downstream area of atmospheric pressure remote plasma

    NASA Astrophysics Data System (ADS)

    Mishin, M. V.; Protopopova, V. S.; Uvarov, A. A.; Alexandrov, S. E.

    2014-10-01

    This paper presents the results from an experimental study of the ion flux characteristics behind the remote plasma zone in a vertical tube reaction chamber for atmospheric pressure plasma enhanced chemical vapor deposition. Capacitively coupled radio frequency plasma was generated in pure He and gas mixtures: He-Ar, He-O2, He-TEOS. We previously used the reaction system He-TEOS for the synthesis of self-assembled structures of silicon dioxide nanoparticles. It is likely that the electrical parameters of the area, where nanoparticles have been transported from the synthesis zone to the substrate, play a significant role in the self-organization processes both in the vapor phase and on the substrate surface. The results from the spatial distribution of the electrical potential and ion concentration in the discharge downstream area measured by means of the external probe of original design and the special data processing method are demonstrated in this work. Positive and negatives ions with maximum concentrations of 106-107 cm-3 have been found at 10-80 mm distance behind the plasma zone. On the basis of the revealed distributions for different gas mixtures, the physical model of the observed phenomena is proposed. The model illustrates the capability of the virtual ion emitter formation behind the discharge gap and the presence of an extremum of the electrical potential at the distance of approximately 10-2-10-1 mm from the grounded electrode.

  18. Water saving at the field scale with Irrig-OH, an open-hardware environment device for soil water potential monitoring and irrigation management

    NASA Astrophysics Data System (ADS)

    Masseroni, Daniele; Facchi, Arianna; Gandolfi, Claudio

    2015-04-01

    Sustainability of irrigation practices is an important objective which should be pursued in many countries, especially in areas where water scarcity causes strong conflicts among the different water uses. The efficient use of water is a key factor in coping with the food demand of an increasing world population and with the negative effects of the climate change on water resources availability in many areas. In this complex context, it is important that farmers adopt instruments and practices that enable a better management of water at the field scale, whatever the irrigation method they adopt. This work presents the hardware structure and the functioning of an open-hardware microstation based on the Arduino technology, called Irrig-OH, which allows the continuous and low-cost monitoring of the soil water potential (SWP) in the root zone for supporting the irrigation scheduling at the field scale. In order to test the microstation, an experiment was carried out during the agricultural season 2014 at Lodi (Italy), with the purpose of comparing the farmers' traditional management of irrigation of a peach variety and the scheduling based on the SWP measurements provided by the microstation. Additional measurements of leaf water potential (LWP), stomatal resistance, transpiration (T), crop water stress index (CWSI) and fruit size evolution were performed respectively on leafs and fruits for verifying the plant physiological responses on different SWP levels in soil. At the harvesting time, the peach production in term of quantity and quality (sucrose content was measured by a rifractometer over a sample of one hundred fruits) of the two rows were compared. Irrigation criteria was changed with respect to three macro-periods: up to the endocarp hardening phase (begin of May) soil was kept well watered fixing the SWP threshold in the first 35 cm of the soil profile at -20 kPa, during the pit hardening period (about the entire month of May) the allowed SWP threshold was

  19. Two-dimensional spatial survey of the plasma potential and electric field in a pulsed bipolar magnetron discharge

    SciTech Connect

    Vetushka, A.; Karkari, S.K.; Bradley, J.W.

    2004-11-01

    Emissive and Langmuir probe techniques have been used to obtain two-dimensional (2D) spatial maps of the plasma potential V{sub p}, electric field E, and ion trajectories in a pulsed bipolar magnetron discharge. The magnetron was pulsed at a frequency of 100 kHz, with a 50% duty cycle and operated at an argon pressure of 0.74 Pa. The pulse wave form was characterized by three distinct phases: the 'overshoot', 'reverse', and 'on' phases. In the 'on' phase of the pulse, when the cathode voltage is driven to -670 V, the 2D spatial distribution of V{sub p} has a similar form to that in dc magnetron, with significant axial and radial electric fields in the bulk plasma, accelerating ions to the sheath edge above the cathode racetrack region. During the 'overshoot' phase (duration 200 ns), V{sub p} is raised to values greater than +330 V, more than 100 V above the cathode potential, with E pointing away from the target. In the 'reverse' phase V{sub p} has a value of +45 V at all measured positions, 2 V more positive than the target potential. In this phase there is no electric field present in the plasma. In the bulk of the plasma, the results from Langmuir probe and the emissive probe are in good agreement, however, in one particular region of the plasma outside the radius of the cathode, the emissive probe measurements are consistently more positive (up to 45 V in the 'on' time). This discrepancy is discussed in terms of the different frequency response of the probes and their perturbation of the plasma. A simple circuit model of the plasma-probe system has been proposed to explain our results. A brief discussion of the effect of the changing plasma potential distribution on the operation of the magnetron is given.

  20. The potential role of electric fields and plasma barodiffusion on the inertial confinement fusion databasea)

    NASA Astrophysics Data System (ADS)

    Amendt, Peter; Wilks, S. C.; Bellei, C.; Li, C. K.; Petrasso, R. D.

    2011-05-01

    The generation of strong, self-generated electric fields (GV/m) in direct-drive, inertial-confinement-fusion (ICF) capsules has been reported [Rygg et al., Science 319, 1223 (2008); Li et al., Phys. Rev. Lett. 100, 225001 (2008)]. A candidate explanation for the origin of these fields based on charge separation across a plasma shock front was recently proposed [Amendt et al., Plasma Phys. Controlled Fusion 51 124048 (2009)]. The question arises whether such electric fields in imploding capsules can have observable consequences on target performance. Two well-known anomalies come to mind: (1) an observed ≈2× greater-than-expected deficit of neutrons in an equimolar D3He fuel mixture compared with hydrodynamically equivalent D [Rygg et al., Phys. Plasmas 13, 052702 (2006)] and DT [Herrmann et al., Phys. Plasmas 16, 056312 (2009)] fuels, and (2) a similar shortfall of neutrons when trace amounts of argon are mixed with D in indirect-drive implosions [Lindl et al., Phys. Plasmas 11, 339 (2004)]. A new mechanism based on barodiffusion (or pressure gradient-driven diffusion) in a plasma is proposed that incorporates the presence of shock-generated electric fields to explain the reported anomalies. For implosions performed at the Omega laser facility [Boehly et al., Opt. Commun. 133, 495 (1997)], the (low Mach number) return shock has an appreciable scale length over which the lighter D ions can diffuse away from fuel center. The depletion of D fuel is estimated and found to lead to a corresponding reduction in neutrons, consistent with the anomalies observed in experiments for both argon-doped D fuels and D3He equimolar mixtures. The reverse diffusional flux of the heavier ions toward fuel center also increases the pressure from a concomitant increase in electron number density, resulting in lower stagnation pressures and larger imploded cores in agreement with gated, self-emission, x-ray imaging data.

  1. A model for estimation of potential generation of waste electrical and electronic equipment in Brazil

    SciTech Connect

    Araujo, Marcelo Guimaraes; Magrini, Alessandra; Mahler, Claudio Fernando; Bilitewski, Bernd

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Literature of WEEE generation in developing countries is reviewed. Black-Right-Pointing-Pointer We analyse existing estimates of WEEE generation for Brazil. Black-Right-Pointing-Pointer We present a model for WEEE generation estimate. Black-Right-Pointing-Pointer WEEE generation of 3.77 kg/capita year for 2008 is estimated. Black-Right-Pointing-Pointer Use of constant lifetime should be avoided for non-mature market products. - Abstract: Sales of electrical and electronic equipment are increasing dramatically in developing countries. Usually, there are no reliable data about quantities of the waste generated. A new law for solid waste management was enacted in Brazil in 2010, and the infrastructure to treat this waste must be planned, considering the volumes of the different types of electrical and electronic equipment generated. This paper reviews the literature regarding estimation of waste electrical and electronic equipment (WEEE), focusing on developing countries, particularly in Latin America. It briefly describes the current WEEE system in Brazil and presents an updated estimate of generation of WEEE. Considering the limited available data in Brazil, a model for WEEE generation estimation is proposed in which different methods are used for mature and non-mature market products. The results showed that the most important variable is the equipment lifetime, which requires a thorough understanding of consumer behavior to estimate. Since Brazil is a rapidly expanding market, the 'boom' in waste generation is still to come. In the near future, better data will provide more reliable estimation of waste generation and a clearer interpretation of the lifetime variable throughout the years.

  2. Potential benefits of long-distance electricity transmission in China for air quality and climate

    NASA Astrophysics Data System (ADS)

    Peng, W.; Mauzerall, D. L.; Yuan, J.; Zhao, Y.; Lin, M.; Zhang, Q.

    2015-12-01

    China is expanding west-to-east long-distance electricity transmission capacity with the aim of reducing eastern coal power production and resulting air pollution. In addition to coal power, this new grid capacity can be used to transport renewable-generated electricity with resulting climate co-benefits. Here we use an integrated assessment to evaluate the air quality and climate benefits of twelve proposed transmission lines in China, and compare two energy-by-wire strategies that transmit 1) only coal power (Coal-by-wire, CbW) or 2) combined renewable plus coal power (Renewable and coal-by-wire, (RE+C)bW), with 3) the current practice of transporting coal by rail for conversion to electricity near eastern demand centers (Coal-by-rail, CbR). Based on a regional atmospheric chemistry model, WRF-Chem, electricity transmission through the proposed lines leads to 2-3 μg/m3 (2-7%) reduction in the annual mean concentrations of fine particulate matter (PM2.5) in the eastern provinces relative to 2010 levels, roughly ~1 μg/m3 greater than the reduction achieved in CbR where dirty coal units are locally replaced with efficient ones. Although the eastern air quality improvement is similar irrespective of the fuel source to power the lines, adding coal generation results in up to 3% increase in annual mean PM2.5 levels in some exporting provinces, whereas such increase is not observed when most added capacity is renewable-based. Counting both the economic value of reduced carbon emissions and the health-related air quality benefits can significantly improve the cost-effectiveness of transmitting both renewable and coal power. Comparing (RE+C)bW with the two coal-based options, we find not only 20% larger reduction in air-pollution-related deaths, but also three times greater reduction in CO2 emissions. Our study hence demonstrates the significance of coordinating renewable energy planning with transmission planning to simultaneously tackle air pollution and climate

  3. Cardiac effects of anabolic steroids: hypertrophy, ischemia and electrical remodelling as potential triggers of sudden death.

    PubMed

    Nascimento, J H M; Medei, E

    2011-05-01

    Anabolic-androgenic steroids (AAS) are synthetic testosterone derivatives developed to maximise anabolic activity and minimise androgenic activity. AAS abuse is widespread among both athletes and non-athletes at fitness centres and is becoming a public health issue. In addition to their atherogenic, thrombogenic and spastic effects, AAS have direct cardiotoxic effects by causing hypertrophy, electrical and structural remodelling, and contractile dysfunction and by increasing the susceptibility to ischemic injuries. All of these factors contribute to an increased risk of ventricular arrhythmias and sudden cardiac death.

  4. Measured energy savings and performance of power-managed personal computers and monitors

    SciTech Connect

    Nordman, B.; Piette, M.A.; Kinney, K.

    1996-08-01

    Personal computers and monitors are estimated to use 14 billion kWh/year of electricity, with power management potentially saving $600 million/year by the year 2000. The effort to capture these savings is lead by the US Environmental Protection Agency`s Energy Star program, which specifies a 30W maximum demand for the computer and for the monitor when in a {open_quote}sleep{close_quote} or idle mode. In this paper the authors discuss measured energy use and estimated savings for power-managed (Energy Star compliant) PCs and monitors. They collected electricity use measurements of six power-managed PCs and monitors in their office and five from two other research projects. The devices are diverse in machine type, use patterns, and context. The analysis method estimates the time spent in each system operating mode (off, low-, and full-power) and combines these with real power measurements to derive hours of use per mode, energy use, and energy savings. Three schedules are explored in the {open_quotes}As-operated,{close_quotes} {open_quotes}Standardized,{close_quotes} and `Maximum` savings estimates. Energy savings are established by comparing the measurements to a baseline with power management disabled. As-operated energy savings for the eleven PCs and monitors ranged from zero to 75 kWh/year. Under the standard operating schedule (on 20% of nights and weekends), the savings are about 200 kWh/year. An audit of power management features and configurations for several dozen Energy Star machines found only 11% of CPU`s fully enabled and about two thirds of monitors were successfully power managed. The highest priority for greater power management savings is to enable monitors, as opposed to CPU`s, since they are generally easier to configure, less likely to interfere with system operation, and have greater savings. The difficulties in properly configuring PCs and monitors is the largest current barrier to achieving the savings potential from power management.

  5. Nanoparticle-enhanced electrical impedance detection and its potential significance in image tomography

    PubMed Central

    Liu, Ran; Jin, Cuiyun; Song, Fengjuan; Liu, Jing

    2013-01-01

    The conductivity and permittivity of tumors are known to differ significantly from those of normal tissues. Electrical impedance tomography (EIT) is a relatively new imaging method for exploiting these differences. However, the accuracy of data capture is one of the difficult problems urgently to be solved in the clinical application of EIT technology. A new concept of EIT sensitizers is put forward in this paper with the goal of expanding the contrast ratio of tumor and healthy tissue to enhance EIT imaging quality. The use of nanoparticles for changing tumor characteristics and determining the infiltration vector for easier detection has been widely accepted in the biomedical field. Ultra-pure water, normal saline, and gold nanoparticles, three kinds of material with large differences in electrical characteristics, are considered as sensitizers and undergo mathematical model analysis and animal experimentation. Our preliminary results suggest that nanoparticles are promising for sensitization work. Furthermore, in experimental and simulation results, we found that we should select different sensitizers for the detection of different types and stages of tumor. PMID:23319858

  6. Electric quadrupole transitions of the Bohr Hamiltonian with Manning-Rosen potential

    NASA Astrophysics Data System (ADS)

    Chabab, M.; El Batoul, A.; Lahbas, A.; Oulne, M.

    2016-09-01

    Analytical expressions of the wave functions are derived for a Bohr Hamiltonian with the Manning-Rosen potential in the cases of γ-unstable nuclei and axially symmetric prolate deformed ones with γ ≈ 0. By exploiting the results we have obtained in a recent work on the same theme Ref. [1], we have calculated the B (E 2) transition rates for 34 γ-unstable and 38 rotational nuclei and compared to experimental data, revealing a qualitative agreement with the experiment and phase transitions within the ground state band and showing also that the Manning-Rosen potential is more appropriate for such calculations than other potentials.

  7. A Heuristic Potential Theory of Electric and Magnetic Monopoles without Strings.

    ERIC Educational Resources Information Center

    Barker, William A.; Graziani, Frank

    1978-01-01

    Shows how Maxwell's equations can be obtained by starting with a relatively simple pseudoscalar and scalar potential employing only the Lorentz transformation for a four vector (or pseudovector). (GA)

  8. Earthquake Lights and Electric Ground Potentials Following the South Napa Earthquake

    NASA Astrophysics Data System (ADS)

    Freund, F. T.; Scoville, J.; Heraud, J. A.; Spremo, S.; Sornette, J.; Kosovichev, P.; Baney, O. N.

    2014-12-01

    Earthquake lights (EQLs) in form of bright flashes have been documented multiple times by private security cameras during and after the M6.0 South Napa earthquake of Aug. 24, 2014. On the video records, series of flashes are seen rising out of the ground, sometimes in rapid succession, at other times as single events brightly illuminating the night sky. The EQLs appear to come from extended sources, probably up to hundreds of meters in lateral extent. Though few video records display accurate GPS-timing, most of the flashes were clearly co-seismic in the sense that they coincided with the local arrival of the seismic waves. This pattern is consistent with records obtained by a surveillance camera and a seismometer co-located on the PUCP campus in Lima, Peru, during the arrival of the P and S waves from the M8.0 Pisco earthquake about 150 km to the southeast of Lima. Analysis of the PUCP and other video records, plus a number of eyewitness reports, indicate that the EQLs were associated (i) with the S waves and (ii) with mafic dykes. Attempts to see to detect the Napa EQLs on records of the GOES satellite were unsuccessful. Unusual conditions have to exist to produce electric discharges at the Earth's surface that can rise 100-200 m into the sky. Key to understanding the underlying processes is the fact that, when mafic rocks are stressed, positive hole charge carriers become activated, i.e. defect electrons in the oxygen anion sublattice. The higher the stress rate, the higher the currents, reaching currents on the order of 1-2 billion A/km3 during compaction of gabbro within 1-2 msec. Obviously, when S waves pass through rocks at velocities around 3.4 km/sec, large numbers of positive holes appear. Flowing out of the stressed rock volume they can create very high electric fields, leading to a number of follow-on processes including corona discharges. In Campbell near San Jose, about 60 km south of Napa, a security camera, motion-triggered by the arrival of the

  9. Quantum description of an atom with an induced electric dipole moment under the effects of rotation and a linear potential

    NASA Astrophysics Data System (ADS)

    Oliveira, A. B.; Bakke, K.

    2016-08-01

    A quantum description of a neutral particle (atom or molecule) with an induced electric dipole moment in a region with an effective magnetic field under the effects of rotation and a linear scalar potential is discussed. It is shown that analytical solutions to the Schrödinger equation can be achieved. Besides, it is shown that the degeneracy of the Landau-type levels is broken and there exists a restriction on the possible values of the cyclotron frequency associated with the Landau-type system.

  10. Rotation of the ionospheric electric potential caused by spatial gradients of ionospheric conductivity

    NASA Astrophysics Data System (ADS)

    Nakamizo, A.; Yoshikawa, A.; Ohtani, S.; Ieda, A.; Seki, K.

    2013-12-01

    The present study focuses on the relationship between the inhomogeneity of the ionospheric conductivity and the rotation of the ionospheric potential. By applying a simplified version of the Hall-conjugate separation method [Yoshikawa, in preparation] to a global ionospheric potential solver, we analyze calculated potential structures separating them into the primary field and secondary field (the polarization field generated by the Hall effect). Calculations are performed with the following conditions for simplification. Here we call the diagonal and off-diagonal components of the conductivity tensor used in the potential solver SGTT/SGPP and SGTP, respectively, and we regard them as Pedersen and Hall conductivities for the high-latitude region. Besides, we call SGTP 'effective-Hall conductivity' based on its characteristics. (1) The input is a dawn-dusk and day-night symmetric R1-FAC. (2) The basic conductivity distribution is homogeneous in the longitudinal direction with only the latitudinal gradient by solar EUV and equatorial enhancement, no day-night difference and no auroral enhancement. (3) From the basic distribution, SGTP is changed with respect to the fixed SGTT/SGPP with the Hall-Pedersen ratio and offset that are applied globally. It is confirmed that the rotation angle (polarization field) is not so changed when we add only offsets but it becomes larger as the Hall-Pedersen ratio increases. This result is not only consistent with a theoretical prediction [Yoshikawa et al., 2013b] but also provides the fact that the ionospheric internal process, the primary-secondary fields generation process, does affect largely on the potential structure, and eventually on the magnetosphere-ionosphere processes. By combining the previously obtained and current results, we will clarify how the potential structure is actually described by the primary field and secondary field. The results can be applied to qualitatively/quantitatively identify the ionospheric causes

  11. A review of properties and potential aerospace applications of electrically conducting polymers

    NASA Technical Reports Server (NTRS)

    Meador, Mary Ann B.; Gaier, James R.; Good, Brian S.; Sharp, G. Richard; Meador, Michael A.

    1990-01-01

    An overview of current research in conducting polymers is presented. Emphasis is placed on development of materials useful for aeronautic and space applications. Research on organic conducting polymers began in the early 1970s with the discovery of polyacetylene. Since then, many polymers which share structural characteristics with polyacetylene have been prepared which conduct electricity, especially when they are doped with suitable agents. Problems with environmental instability, difficult processing, poor mechanical properties and high cost have slowed the development of conducting polymers. However, practical use of these materials is imminent, based on recent refinements in understanding how polymers conduct, more systematic approaches to the development of new materials, and significant improvements in both the processing and properties.

  12. Potential for cogeneration of heat and electricity in California industry, phase 2

    NASA Technical Reports Server (NTRS)

    Davis, H. S.; Edelson, E.; Kashani, A. K.; Slonski, M. L.

    1979-01-01

    The nontechnical issues of industrial cogeneration for 12 California firms were analyzed under three categories of institutional settings: (1) industrial ownership without firm sales of power; (2) industrial ownership with firm sales of power; and (3) utility or third party ownership. Institutional issues were analyzed from the independent viewpoints of the primary parties of interest: the industrial firms, the electric utilities and the California Public utilities Commission. Air quality regulations and the agencies responsible for their promulgation were examined, and a life cycle costing model was used to evaluate the economic merits of representative conceptual cogeneration systems at these sites. Specific recommendations were made for mitigating measures and regulatory action relevant to industrial cogeneration in California.

  13. Meridional structures of electric potentials relevant to premidnight discrete auroras: A case study from Akebono measurements

    SciTech Connect

    Yamamoto, Tatsundo; Kaneda, Eisuke; Hayakawa, Hajime

    1993-07-01

    The authors present satellite measurements from Akebono of auroral structures from UV images, from particle measurements, and from electric field measurements made at altitudes near 10000 km over the polar region in a period of geomagnetic activity. The effort is to correlate the auroral data, and in particular what is observed at lower altitudes, with measurements at these altitudes of precipitation properties, and field values, to infer information on the contribution of altitudes above and below the satellite to acceleration processes which produce observed aurorae. The regions of observed discrete aurorae are compared with the regions exhibiting particle precipitation, which are commonly associated with plasma sheet sources, and found to not be in good alignment. Such observations are correlated with field observations to develop an altitude picture of field structures in the disturbed polar ionosphere.

  14. A microbial fuel cell in contaminated ground delineated by electrical self-potential and normalized induced polarization data

    NASA Astrophysics Data System (ADS)

    Doherty, R.; Kulessa, B.; Ferguson, A. S.; Larkin, M. J.; Kulakov, L. A.; Kalin, R. M.

    2010-09-01

    There is a growing interest in the use of geophysical methods to aid investigation and monitoring of complex biogeochemical environments, for example delineation of contaminants and microbial activity related to land contamination. We combined geophysical monitoring with chemical and microbiological analysis to create a conceptual biogeochemical model of processes around a contaminant plume within a manufactured gas plant site. Self-potential, induced polarization and electrical resistivity techniques were used to monitor the plume. We propose that an exceptionally strong (>800 mV peak to peak) dipolar SP anomaly represents a microbial fuel cell operating in the subsurface. The electromagnetic and electrical geophysical data delineated a shallow aerobic perched water body containing conductive gasworks waste which acts as the abiotic cathode of microbial fuel cell. This is separated from the plume below by a thin clay layer across the site. Microbiological evidence suggests that degradation of organic contaminants in the plume is dominated by the presence of ammonium and its subsequent degradation. We propose that the degradation of contaminants by microbial communities at the edge of the plume provides a source of electrons and acts as the anode of the fuel cell. We hypothesize that ions and electrons are transferred through the clay layer that was punctured during the trial pitting phase of the investigation. This is inferred to act as an electronic conductor connecting the biologically mediated anode to the abiotic cathode. Integrated electrical geophysical techniques appear well suited to act as rapid, low cost sustainable tools to monitor biodegradation.

  15. Improvement of Electrical Stimulation Protocol for Simultaneous Measurement of Extracellular Potential with On-Chip Multi-Electrode Array System

    NASA Astrophysics Data System (ADS)

    Kaneko, Tomoyuki; Nomura, Fumimasa; Hattori, Akihiro; Yasuda, Kenji

    2012-06-01

    Cardiotoxicity testing with a multi-electrode array (MEA) system requires the stable beating of cardiomyocytes for the measurement of the field potential duration (FPD), because different spontaneous beating rates cause different responses of FPD prolongation induced by drugs, and the beating rate change effected by drugs complicates the FPD prolongation assessment. We have developed an on-chip MEA system with electrical stimulation for the measurement of the FPD during the stable beating of human embryonic stem (ES) cell-derived cardiomyocyte clusters. Using a conventional bipolar stimulation protocol, we observed such large artifacts in electrical stimulation that we could not estimate the FPD quantitatively. Therefore, we improved the stimulation protocol by using sequential rectangular pulses in which the positive and negative stimulation voltages and number of pulses could be changed flexibly. The balanced voltages and number of pulses for sequential rectangular pulses enabled the recording of small negative artifacts only, which hardly affected the FPD measurement of human-ES-cell-derived cardiomyocyte clusters. These conditions of electrical stimulation are expected to find applications for the control of constant beating for cardiotoxicity testing.

  16. [Research Progress in Technology of Using Soil Micro-organisms to Generate Electricity and Its Potential Applications].

    PubMed

    Deng, Huan; Xue, Hong-jing; Jiang, Yun-bin; Zhong, Wen-hui

    2015-10-01

    Microbial fuel cells ( microbial fuel cells, MFCs) are devices in which micro-organisms convert chemical energy into electrical power. Soil has electrogenic bacteria and organic substrates, thus can generate electrical current in MFCs. Soil MFCs can be operated and applied to real-time and continuously monitor soil pollution, remove soil pollutants and to reduce methane emitted from flooded rice paddy, without energy consumption and the application of chemical reagents to the soil. Instead, the operation of soil MFCs generates small amount of electrical power. Therefore, soil MFCs are useful in the development of environment-friendly technology for monitoring and remediating soil pollution, which have potential value for applications in the domain of environmental science and engineering. However, much of advanced technology hasn't been applied into soil MFCs since the studies on soil MFCs was not started until recently. This paper summarized the research progress in related to soil MFCs combining with the frontier of MFCs technology, and brought forward the possible direction in studies on soil MFCs. PMID:26841633

  17. [Research Progress in Technology of Using Soil Micro-organisms to Generate Electricity and Its Potential Applications].

    PubMed

    Deng, Huan; Xue, Hong-jing; Jiang, Yun-bin; Zhong, Wen-hui

    2015-10-01

    Microbial fuel cells ( microbial fuel cells, MFCs) are devices in which micro-organisms convert chemical energy into electrical power. Soil has electrogenic bacteria and organic substrates, thus can generate electrical current in MFCs. Soil MFCs can be operated and applied to real-time and continuously monitor soil pollution, remove soil pollutants and to reduce methane emitted from flooded rice paddy, without energy consumption and the application of chemical reagents to the soil. Instead, the operation of soil MFCs generates small amount of electrical power. Therefore, soil MFCs are useful in the development of environment-friendly technology for monitoring and remediating soil pollution, which have potential value for applications in the domain of environmental science and engineering. However, much of advanced technology hasn't been applied into soil MFCs since the studies on soil MFCs was not started until recently. This paper summarized the research progress in related to soil MFCs combining with the frontier of MFCs technology, and brought forward the possible direction in studies on soil MFCs.

  18. The Conservation Nexus: Valuing Interdependent Water and Energy Savings in Phoenix, Arizona

    NASA Astrophysics Data System (ADS)

    Chester, M.; Bartos, M.

    2013-12-01

    Energy and water resources are intrinsically linked, yet they are managed separately--even in the water-scarce American southwest. This study develops a spatially-explicit model of water-energy interdependencies in Arizona, and assesses the potential for co-beneficial conservation programs. Arizona consumes 2.8% of its water demand for thermoelectric power and 8% of its electricity demand for water infrastructure--roughly twice the national average. The interdependent benefits of investments in 7 conservation strategies are assessed. Deployment of irrigation retrofits and new reclaimed water facilities dominate potential water savings, while residential and commercial HVAC improvements dominate energy savings. Water conservation policies have the potential to reduce statewide electricity demand by 1.0-2.9%, satisfying 5-14% of mandated energy-efficiency goals. Likewise, adoption of energy-efficiency measures and renewable generation portfolios can reduce non-agricultural water demand by 2.0-2.6%. These co-benefits of conservation investments are typically not included in conservation plans or benefit-cost analyses. Residential water conservation measures produce significant water and energy savings, but are generally not cost-effective at current water prices. An evaluation of the true cost of water in Arizona would allow future water and energy savings to be compared objectively, and would help policymakers allocate scarce resources to the highest-value conservation measures. Water Transfers between Water Cycle Components in Arizona in 2008 Cumulative embedded energy in water cycle components in Arizona in 2008

  19. Measuring the electric charge and zeta potential of nanometer-sized objects using pyramidal-shaped nanopores.

    PubMed

    Arjmandi, Nima; Van Roy, Willem; Lagae, Liesbet; Borghs, Gustaaf

    2012-10-16

    Nanometer-scale pores are capable of detecting the size and concentration of nanometer-sized analytes at low concentrations upon analyzing their translocation through the pore, in small volumes and over a short time without labeling. Here, we present a simple, widely applicable, robust, and precise method to measure the zeta-potential of different nano-objects using nanopores. Zeta-potential i.e., a quantity that represents electrical charge in nanocolloids, is an important property in manufacturing of pharmaceuticals, inks, foams, cosmetics, and food. Its use is also imperative in understanding basic properties of complex dispersions including blood, living organisms, and their interaction with the environment. The characterization methods for zeta-potential are limited. Using the nanopore technique, the zeta-potential and the charge of nanoparticles can be measured independently of other parameters, such as particle size. This simple method is based on measuring the duration of the translocation of analytes through a nanopore as a function of applied voltage. A simple analytical model has been developed to extract the zeta-potential. This method is able to detect and differentiate nanometer-sized objects of similar size; it also enables the direct and precise quantitative measurement of their zeta-potential. We have applied this method to a wide range of different nanometer-sized particles and compared the results with values measured by commercially available tools. Furthermore, potential capability of this method in detection and characterization of virions is shown by measuring the low zeta-potential of HIV and EBV viruses.

  20. The effect of amiloride on the resting potential and the electrical constants of frog skeletal muscle fibres.

    PubMed Central

    Estrada, F; Sanchez, J A

    1991-01-01

    1. The effects of amiloride on the membrane potential of frog skeletal muscle fibres were investigated with a single intracellular microelectrode. Two microelectrode current- and voltage-clamp experiments were also performed to determine the effects of amiloride on the electrical constants and membrane current near the resting potential. 2. Amiloride reversibly hyperpolarized muscle fibres up to ca 12 mV in 2.5 mM-K+, in a concentration-dependent manner, with a half-maximum effect at 0.2 mM. Amiloride (0.4 mM) also significantly increased the membrane resistance of muscle fibres. 3. The effects of amiloride were consistent with the classical theory of the resting potential and could be described by assuming that it removes the Na+ permeability factor in the Goldman-Hodgkin-Katz equation for [K+]o > or = 2.5 mM. 4. Replacement of [Na+]o by N-methyl-glucamine, choline or Mg2+ produced smaller effects on the resting potential and on membrane resistance than those induced by amiloride. 5. It is concluded that an amiloride-sensitive poorly selective conductance continuously depolarizes the cellular membrane thus playing a role in the resting potential of frog skeletal muscle. PMID:1668756