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Sample records for fuel recharge problem

  1. Oxygen electrodes for rechargeable alkaline fuel cells

    NASA Technical Reports Server (NTRS)

    Swette, Larry; Giner, Jose

    1987-01-01

    Electrocatalysts and supports for the positive electrode of moderate temperature single unit rechargeable alkaline fuel cells were investigated and developed. The electrocatalysts are defined as the material with a higher activity for the oxygen electrode reaction than the support. Advanced development will require that the materials be prepared in high surface area forms, and may also entail integration of various candidate materials. Eight candidate support materials and seven electrocatalysts were investigated. Of the 8 support, 3 materials meet the preliminary requirements in terms of electrical conductivity and stability. Emphasis is now on preparing in high surface area form and testing under more severe corrosion stress conditions. Of the 7 electrocatalysts prepared and evaluated, at least 5 materials remain as potential candidates. The major emphasis remains on preparation, physical characterization and electrochemical performance testing.

  2. Karst and artificial recharge: Theoretical and practical problems. A preliminary approach to artificial recharge assessment

    NASA Astrophysics Data System (ADS)

    Daher, Walid; Pistre, Séverin; Kneppers, Angeline; Bakalowicz, Michel; Najem, Wajdi

    2011-10-01

    SummaryManaged Aquifer Recharge (MAR) is an emerging sustainable technique that has already generated successful results and is expected to solve many water resource problems, especially in semi-arid and arid zones. It is of great interest for karst aquifers that currently supply 20-25% of the world's potable water, particularly in Mediterranean countries. However, the high heterogeneity in karst aquifers is too complex to be able to locate and describe them simply via field observations. Hence, as compared to projects in porous media, MAR is still marginal in karst aquifers. Accordingly, the present work presents a conceptual methodology for Aquifer Rechargeability Assessment in Karst - referred to as ARAK. The methodology was developed noting that artificial recharge in karst aquifers is considered an improbable challenge to solve since karst conduits may drain off recharge water without any significant storage, or recharge water may not be able to infiltrate. The aim of the ARAK method is to determine the ability of a given karst aquifer to be artificially recharged and managed, and the best sites for implementing artificial recharge from the surface. ARAK is based on multi-criteria indexation analysis modeled on karst vulnerability assessment methods. ARAK depends on four independent criteria, i.e. Epikarst, Rock, Infiltration and Karst. After dividing the karst domain into grids, these criteria are indexed using geological and topographic maps refined by field observations. ARAK applies a linear formula that computes the intrinsic rechargeability index based on the indexed map for every criterion, coupled with its attributed weighting rate. This index indicates the aptitude for recharging a given karst aquifer, as determined by studying its probability first on a regional scale for the whole karst aquifer, and then by characterizing the most favorable sites. Subsequently, for the selected sites, a technical and economic feasibility factor is applied, weighted by the difficulties that could occur when trying to undertake a recharge operation at a selected site from the surface. Each site is finally rated by its rechargeability index - the product of two factors, the intrinsic rechargeability and the feasibility index. ARAK was applied to the region of Damour, Lebanon, on the Mediterranean coast where uncontrolled exploitation of public and private wells led to its partial salinization by seawater. A MAR system in Damour region represents an interesting solution to cope with salinization and the insufficiency of the resource.

  3. Oxygen electrodes for rechargeable alkaline fuel cells-II

    NASA Technical Reports Server (NTRS)

    Swette, L.; Kackley, N.

    1989-01-01

    The primary objective of this program is the investigation and development of electrocatalysts and supports for the positive electrode of moderate temperature single-unit rechargeable alkaline fuel cells. Approximately six support materials and five catalyst materials have been identified to date for further development.

  4. Theoretical performance of hydrogen-bromine rechargeable SPE fuel cell

    NASA Technical Reports Server (NTRS)

    Savinell, Robert F.; Fritts, S. D.

    1987-01-01

    A mathematical model was formulated to describe the performance of a hydrogen-bromine fuel cell. Porous electrode theory was applied to the carbon felt flow-by electrode and was coupled to theory describing the solid polymer electrolyte (SPE) system. Parametric studies using the numerical solution to this model were performed to determine the effect of kinetic, mass transfer, and design parameters on the performance of the fuel cell. The results indicate that the cell performance is most sensitive to the transport properties of the SPE membrane. The model was also shown to be a useful tool for scale-up studies.

  5. An overview—Functional nanomaterials for lithium rechargeable batteries, supercapacitors, hydrogen storage, and fuel cells

    SciTech Connect

    Liu, Hua Kun

    2013-12-15

    Graphical abstract: Nanomaterials play important role in lithium ion batteries, supercapacitors, hydrogen storage and fuel cells. - Highlights: • Nanomaterials play important role for lithium rechargeable batteries. • Nanostructured materials increase the capacitance of supercapacitors. • Nanostructure improves the hydrogenation/dehydrogenation of hydrogen storage materials. • Nanomaterials enhance the electrocatalytic activity of the catalysts in fuel cells. - Abstract: There is tremendous worldwide interest in functional nanostructured materials, which are the advanced nanotechnology materials with internal or external dimensions on the order of nanometers. Their extremely small dimensions make these materials unique and promising for clean energy applications such as lithium ion batteries, supercapacitors, hydrogen storage, fuel cells, and other applications. This paper will highlight the development of new approaches to study the relationships between the structure and the physical, chemical, and electrochemical properties of functional nanostructured materials. The Energy Materials Research Programme at the Institute for Superconducting and Electronic Materials, the University of Wollongong, has been focused on the synthesis, characterization, and applications of functional nanomaterials, including nanoparticles, nanotubes, nanowires, nanoporous materials, and nanocomposites. The emphases are placed on advanced nanotechnology, design, and control of the composition, morphology, nanostructure, and functionality of the nanomaterials, and on the subsequent applications of these materials to areas including lithium ion batteries, supercapacitors, hydrogen storage, and fuel cells.

  6. Unitized regenerative fuel cells for solar rechargeable aircraft and zero emission vehicles

    SciTech Connect

    Mitlitsky, F.; Colella, N.J.; Myers, B.

    1994-09-06

    A unitized regenerative fuel cell (URFC) produces power and electrolytically regenerates its reactants using a single stack of reversible cells. URFCs have been designed for high altitude long endurance (HALE) solar rechargeable aircraft (SRA), zero emission vehicles (ZEVs), hybrid energy storage/propulsion systems for long duration satellites, energy storage for remote (off-grid) power sources, and peak shaving for on-grid applications. URFCs have been considered using hydrogen/oxygen, hydrogen/air, or hydrogen/halogen chemistries. This discussion is limited to the lightweight URFC energy storage system designs for span-loaded HALE SRA using hydrogen/oxygen, and for ZEVs using hydrogen/air with oxygen supercharging. Overlapping and synergistic development and testing opportunities for these two technologies will be highlighted.

  7. Problems associated with estimating ground water discharge and recharge from stream-discharge records

    USGS Publications Warehouse

    Halford, K.J.; Mayer, G.C.

    2000-01-01

    Ground water discharge and recharge frequently have been estimated with hydrograph-separation techniques, but the critical assumptions of the techniques have not been investigated. The critical assumptions are that the hydraulic characteristics of the contributing aquifer (recession index) can be estimated from stream-discharge records; that periods of exclusively ground water discharge can be reliably identified; and that stream-discharge peaks approximate the magnitude and tinting of recharge events. The first assumption was tested by estimating the recession index from st earn-discharge hydrographs, ground water hydrographs, and hydraulic diffusivity estimates from aquifer tests in basins throughout the eastern United States and Montana. The recession index frequently could not be estimated reliably from stream-discharge records alone because many of the estimates of the recession index were greater than 1000 days. The ratio of stream discharge during baseflow periods was two to 36 times greater than the maximum expected range of ground water discharge at 12 of the 13 field sites. The identification of the ground water component of stream-discharge records was ambiguous because drainage from bank-storage, wetlands, surface water bodies, soils, and snowpacks frequently exceeded ground water discharge and also decreased exponentially during recession periods. The timing and magnitude of recharge events could not be ascertained from stream-discharge records at any of the sites investigated because recharge events were not directly correlated with stream peaks. When used alone, the recession-curve-displacement method and other hydrograph-separation techniques are poor tools for estimating ground water discharge or recharge because the major assumptions of the methods are commonly and grossly violated. Multiple, alternative methods of estimating ground water discharge and recharge should be used because of the uncertainty associated with any one technique.

  8. Safeguards for spent fuels: Verification problems

    SciTech Connect

    Pillay, K.K.S.; Picard, R.R.

    1991-01-01

    The accumulation of large quantities of spent nuclear fuels world-wide is a serious problem for international safeguards. A number of International Atomic Energy Agency (IAEA) member states, including the US, consider spent fuel to be a material form for which safeguards cannot be terminated, even after permanent disposal in a geologic repository. Because safeguards requirements for spent fuels are different from those of conventional bulk-handling and item-accounting facilities, there is room for innovation to design a unique safeguards regime for spent fuels that satisfies the goals of the nuclear nonproliferation treaty at a reasonable cost to both the facility and the IAEA. Various strategies being pursued for long-term management of spent fuels are examined with a realistic example to illustrate the problems of verifying safeguards under the present regime. Verification of a safeguards regime for spent fuels requires a mix of standard safeguards approaches, such as quantitative verification and use of seals, with other measures that are unique to spent fuels. 17 refs.

  9. Theoretical performance of hydrogen-bromine rechargeable SPE fuel cell. [Solid Polymer Electrolyte

    NASA Technical Reports Server (NTRS)

    Savinell, R. F.; Fritts, S. D.

    1988-01-01

    A mathematical model was formulated to describe the performance of a hydrogen-bromine fuel cell. Porous electrode theory was applied to the carbon felt flow-by electrode and was coupled to theory describing the solid polymer electrolyte (SPE) system. Parametric studies using the numerical solution to this model were performed to determine the effect of kinetic, mass transfer, and design parameters on the performance of the fuel cell. The results indicate that the cell performance is most sensitive to the transport properties of the SPE membrane. The model was also shown to be a useful tool for scale-up studies.

  10. Fuel-optimal trajectories for aeroassisted coplanar orbital transfer problem

    NASA Technical Reports Server (NTRS)

    Naidu, Desineni Subbaramaiah; Hibey, Joseph L.; Charalambous, Charalambos D.

    1990-01-01

    The optimal control problem arising in coplanar orbital transfer employing aeroassist technology is addressed. The maneuver involves the transfer from high to low earth orbit via the atmosphere, with the object of minimizing the total fuel consumption. Simulations are carried out to obtain the fuel-optimal trajectories for flying the spacecraft through the atmosphere. A highlight is the application of an efficient multiple-shooting method for treating the nonlinear two-point boundary value problem resulting from the optimizaion procedure. The strategy for the atmospheric portion of the minimum-fuel transfer is to fly at the maximum lift-to-drag ratio L/D initially in order to recover from the downward plunge, and then to fly at a negative L/D to level off the flight so that the vehicle skips out of the atmosphere with a flight path angle near zero degrees.

  11. Fuel-optimal trajectories for aeroassisted coplanar orbital transfer problem

    NASA Technical Reports Server (NTRS)

    Naidu, D. S.; Hibey, J. L.; Charalambous, C.

    1988-01-01

    The optimal-control problem arising in coplanar orbital transfer using aeroassist technology is addressed. The maneuver involves the transfer from high earth orbit to low earth orbit with minimum fuel consumption. Simulations are carried out to obtain a corridor of entry conditions which are suitable for flying the spacecraft through the atmosphere. A highlight of the present work is the application of an efficient multiple shooting method for handling the difficult nonlinear two-point boundary value problem resulting from the optimization procedure.

  12. An ultrafast rechargeable aluminium-ion battery

    NASA Astrophysics Data System (ADS)

    Lin, Meng-Chang; Gong, Ming; Lu, Bingan; Wu, Yingpeng; Wang, Di-Yan; Guan, Mingyun; Angell, Michael; Chen, Changxin; Yang, Jiang; Hwang, Bing-Joe; Dai, Hongjie

    2015-04-01

    The development of new rechargeable battery systems could fuel various energy applications, from personal electronics to grid storage. Rechargeable aluminium-based batteries offer the possibilities of low cost and low flammability, together with three-electron-redox properties leading to high capacity. However, research efforts over the past 30 years have encountered numerous problems, such as cathode material disintegration, low cell discharge voltage (about 0.55 volts ref. 5), capacitive behaviour without discharge voltage plateaus (1.1-0.2 volts or 1.8-0.8 volts) and insufficient cycle life (less than 100 cycles) with rapid capacity decay (by 26-85 per cent over 100 cycles). Here we present a rechargeable aluminium battery with high-rate capability that uses an aluminium metal anode and a three-dimensional graphitic-foam cathode. The battery operates through the electrochemical deposition and dissolution of aluminium at the anode, and intercalation/de-intercalation of chloroaluminate anions in the graphite, using a non-flammable ionic liquid electrolyte. The cell exhibits well-defined discharge voltage plateaus near 2 volts, a specific capacity of about 70 mA h g-1 and a Coulombic efficiency of approximately 98 per cent. The cathode was found to enable fast anion diffusion and intercalation, affording charging times of around one minute with a current density of ~4,000 mA g-1 (equivalent to ~3,000 W kg-1), and to withstand more than 7,500 cycles without capacity decay.

  13. Electrical isolation problems in underground fuel storage tanks and piping

    SciTech Connect

    Vessel, E.M.; Jenkins, C.F.

    1994-09-01

    Eleven underground fuel storage tanks have been replaced at the Department of Energy`s Savannah River Site since 1986. The replacement tanks are steel tank-in-tank construction with the exterior surface coated and cathodically protected. The annular space between tanks is monitored for leaks, thus meeting current Federal and State environmental regulations. Piping connected to the tanks is also coated and cathodically protected (CP). The two CP systems are designed to be isolated from each other and from the plant electrical system, in order to improve the efficiency of the anodes by restricting the overall area each protects. Problems with CP arose following maintenance activity at some of the tanks. Investigation showed that the electrical isolation had been violated. This required examination and replacement of several special pipe fittings and bolt isolation kits. A breakdown of communications with maintenance personnel in the field is often the source of problems and in this case led to compromising the corrosion protection.

  14. Closing nuclear fuel cycle with fast reactors: problems and prospects

    SciTech Connect

    Shadrin, A.; Dvoeglazov, K.; Ivanov, V.

    2013-07-01

    The closed nuclear fuel cycle (CNFC) with fast reactors (FR) is the most promising way of nuclear energetics development because it prevents spent nuclear fuel (SNF) accumulation and minimizes radwaste volume due to minor actinides (MA) transmutation. CNFC with FR requires the elaboration of safety, environmentally acceptable and economically effective methods of treatment of SNF with high burn-up and low cooling time. The up-to-date industrially implemented SNF reprocessing technologies based on hydrometallurgical methods are not suitable for the reprocessing of SNF with high burn-up and low cooling time. The alternative dry methods (such as electrorefining in molten salts or fluoride technologies) applicable for such SNF reprocessing have not found implementation at industrial scale. So the cost of SNF reprocessing by means of dry technologies can hardly be estimated. Another problem of dry technologies is the recovery of fissionable materials pure enough for dense fuel fabrication. A combination of technical solutions performed with hydrometallurgical and dry technologies (pyro-technology) is proposed and it appears to be a promising way for the elaboration of economically, ecologically and socially accepted technology of FR SNF management. This paper deals with discussion of main principle of dry and aqueous operations combination that probably would provide safety and economic efficiency of the FR SNF reprocessing. (authors)

  15. Lightweight aircraft engines, the potential and problems for use of automotive fuels

    NASA Technical Reports Server (NTRS)

    Patterson, D. J.

    1983-01-01

    A comprehensive data research and analysis for evaluating the use of automotive fuels as a substitute for aviation grade fuel by piston-type general aviation aircraft engines is presented. Historically known problems and potential problems with fuels were reviewed for possible impact relative to application to an aircraft operational environment. This report reviews areas such as: fuel specification requirements, combustion knock, preignition, vapor lock, spark plug fouling, additives for fuel and oil, and storage stability.

  16. An ultrafast rechargeable aluminium-ion battery.

    PubMed

    Lin, Meng-Chang; Gong, Ming; Lu, Bingan; Wu, Yingpeng; Wang, Di-Yan; Guan, Mingyun; Angell, Michael; Chen, Changxin; Yang, Jiang; Hwang, Bing-Joe; Dai, Hongjie

    2015-04-16

    The development of new rechargeable battery systems could fuel various energy applications, from personal electronics to grid storage. Rechargeable aluminium-based batteries offer the possibilities of low cost and low flammability, together with three-electron-redox properties leading to high capacity. However, research efforts over the past 30 years have encountered numerous problems, such as cathode material disintegration, low cell discharge voltage (about 0.55 volts; ref. 5), capacitive behaviour without discharge voltage plateaus (1.1-0.2 volts or 1.8-0.8 volts) and insufficient cycle life (less than 100 cycles) with rapid capacity decay (by 26-85 per cent over 100 cycles). Here we present a rechargeable aluminium battery with high-rate capability that uses an aluminium metal anode and a three-dimensional graphitic-foam cathode. The battery operates through the electrochemical deposition and dissolution of aluminium at the anode, and intercalation/de-intercalation of chloroaluminate anions in the graphite, using a non-flammable ionic liquid electrolyte. The cell exhibits well-defined discharge voltage plateaus near 2 volts, a specific capacity of about 70 mA h g(-1) and a Coulombic efficiency of approximately 98 per cent. The cathode was found to enable fast anion diffusion and intercalation, affording charging times of around one minute with a current density of ~4,000 mA g(-1) (equivalent to ~3,000 W kg(-1)), and to withstand more than 7,500 cycles without capacity decay. PMID:25849777

  17. Accounting for intracell flow in models with emphasis on water table recharge and stream-aquifer interaction. 1. Problems and concepts

    USGS Publications Warehouse

    Jorgensen, D.G.; Signor, D.C.; Imes, J.L.

    1989-01-01

    One method of modeling multiple sources and sinks is to determine the net recharge per cell. For example, for a model cell containing both a sink and recharge through the water table, the amount of recharge should be reduced by the ratio of the area of influence of the sink within the cell to the area of the cell. The reduction is the intercepted portion of the recharge. In a multilayer model this amount is further reduced by a proportion factor, which is a function of the depth of the flow lines from the water table boundary to the internal sink. A gaining section of a stream is a typical sink. The aquifer contribution to a gaining stream can be conceptualized as having two parts; the first part is the intercepted lateral flow from the water table and the second is the flow across the streambed due to differences in head between the water level in the stream and the aquifer below. The amount intercepted is a function of the geometry of the cell, but the amount due to difference in head across the stream bed is largely independent of cell geometry. -from Authors

  18. Identifying and quantifying urban recharge: a review

    NASA Astrophysics Data System (ADS)

    Lerner, David N.

    2002-02-01

    The sources of and pathways for groundwater recharge in urban areas are more numerous and complex than in rural environments. Buildings, roads, and other surface infrastructure combine with man-made drainage networks to change the pathways for precipitation. Some direct recharge is lost, but additional recharge can occur from storm drainage systems. Large amounts of water are imported into most cities for supply, distributed through underground pipes, and collected again in sewers or septic tanks. The leaks from these pipe networks often provide substantial recharge. Sources of recharge in urban areas are identified through piezometry, chemical signatures, and water balances. All three approaches have problems. Recharge is quantified either by individual components (direct recharge, water-mains leakage, septic tanks, etc.) or holistically. Working with individual components requires large amounts of data, much of which is uncertain and is likely to lead to large uncertainties in the final result. Recommended holistic approaches include the use of groundwater modelling and solute balances, where various types of data are integrated. Urban recharge remains an under-researched topic, with few high-quality case studies reported in the literature.

  19. Results of international standard problem No. 36 severe fuel damage experiment of a VVER fuel bundle

    SciTech Connect

    Firnhaber, M.; Yegorova, L.; Brockmeier, U.

    1995-09-01

    International Standard Problems (ISP) organized by the OECD are defined as comparative exercises in which predictions with different computer codes for a given physical problem are compared with each other and with a carefully controlled experimental study. The main goal of ISP is to increase confidence in the validity and accuracy of analytical tools used in assessing the safety of nuclear installations. In addition, it enables the code user to gain experience and to improve his competence. This paper presents the results and assessment of ISP No. 36, which deals with the early core degradation phase during an unmitigated severe LWR accident in a Russian type VVER. Representatives of 17 organizations participated in the ISP using the codes ATHLET-CD, ICARE2, KESS-III, MELCOR, SCDAP/RELAP5 and RAPTA. Some participants performed several calculations with different codes. As experimental basis the severe fuel damage experiment CORA-W2 was selected. The main phenomena investigated are thermal behavior of fuel rods, onset of temperature escalation, material behavior and hydrogen generation. In general, the calculations give the right tendency of the experimental results for the thermal behavior, the hydrogen generation and, partly, for the material behavior. However, some calculations deviate in important quantities - e.g. some material behavior data - showing remarkable discrepancies between each other and from the experiments. The temperature history of the bundle up to the beginning of significant oxidation was calculated quite well. Deviations seem to be related to the overall heat balance. Since the material behavior of the bundle is to a great extent influenced by the cladding failure criteria a more realistic cladding failure model should be developed at least for the detailed, mechanistic codes. Regarding the material behavior and flow blockage some models for the material interaction as well as for relocation and refreezing requires further improvement.

  20. Research on rechargeable oxygen electrodes

    NASA Technical Reports Server (NTRS)

    Giner, J.; Malachesky, P. A.; Holleck, G.

    1971-01-01

    Studies were carried out on a number of factors which may influence the behavior of the platinum electrocatalyst of oxygen electrodes for use in rechargeable metal-oxygen batteries or hydrogen-oxygen fuel cells. The effects of pretreatments for various potentials and added ionic species, which could be present in such systems, were studied with reguard to: (1) the state of surface oxidation, (2) platinum dissolution, (3) the kinetics of oxygen evolution and reduction (including the role of hydrogen peroxide), and (4) changes in porous electrode structure. These studies were carried out on smooth platinum, platinized platinum, and Teflon-bonded platinum black electrodes in carefully purified electrolyte solutions. The main factors which appear to affect rechargeable oxygen electrode performance and life are: (1) the buildup of a refractory anodic layer on extended cycling, and (2) the dissolution of platinum.

  1. The problem of liquid fuels (for aircraft engines)

    NASA Technical Reports Server (NTRS)

    Gallo, Gino

    1924-01-01

    The crisis which troubles the world market for liquid fuel in general and for carburants in particular is doubtless one of the most serious ever experienced by modern industry. It is a national crisis of economic and political independence for countries like Italy and France. The solutions suggested for meeting the lack of liquid fuel may be summed up under two general headings: the economical use of the petroleum now available; creation of petroleum substitutes from natural sources within the country. The process of cracking is described at length.

  2. Rechargeable Aluminum-Ion Batteries

    SciTech Connect

    Paranthaman, Mariappan Parans; Liu, Hansan; Sun, Xiao-Guang; Dai, Sheng; Brown, Gilbert M

    2015-01-01

    This chapter reports on the development of rechargeable aluminum-ion batteries. A possible concept of rechargeable aluminum/aluminum-ion battery based on low-cost, earth-abundant Al anode, ionic liquid EMImCl:AlCl3 (1-ethyl-3-methyl imidazolium chloroaluminate) electrolytes and MnO2 cathode has been proposed. Al anode has been reported to show good reversibility in acid melts. However, due to the problems in demonstrating the reversibility in cathodes, alternate battery cathodes and battery concepts have also been presented. New ionic liquid electrolytes for reversible Al dissolution and deposition are needed in the future for replacing corrosive EMImCl:AlCl3 electrolytes.

  3. Conclusions and recommendations. [for problems in energy situation, air transportation, and hydrogen fuel

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Conclusions and recommendations are presented for an analysis of the total energy situation; the effect of the energy problem on air transportation; and hydrogen fuel for aircraft. Properties and production costs of fuels, future prediction for energy and transportation, and economic aspects of hydrogen production are appended.

  4. Spacecraft fuel-optimal and balancing maneuvers for a class of formation reconfiguration problems

    NASA Astrophysics Data System (ADS)

    Yoo, Sung-Moon; Lee, Sangjin; Park, Chandeok; Park, Sang-Young

    2013-10-01

    This paper presents fuel optimal and balancing methodologies for reconfiguring multiple spacecraft in formation subject to a Newtonian gravity field. For a kind of continuous-thrust propulsion system, a fuel-optimal control problem is formulated to minimize the integral squared control subject to the linearized Hill or Clohessy-Wiltshire dynamics of relative motion with respect to a circular reference orbit. Palmer's analytical solution for general reconfiguration is adapted to maneuvers between projected circular orbits, resulting in the optimal fuel consumption index as a function of configuration parameters such as orbit radius, phase angle, and transfer time. Parametric analyses reveal unique characteristics of individual fuel optimality and gross fuel consumption: for an arbitrary selection of initial/terminal orbit radii, (i) there exist special transfer times such that individual fuel consumption is optimally uniform for all phase angles, and (ii) the total fuel expenditure for a group of three or more spacecraft is invariant for the relatively same configuration with respect to the departure phase. These results serve to effectively design fuel balancing strategies for formation reconfiguration of multiple spacecraft.

  5. Rechargeable hybrid aqueous batteries

    NASA Astrophysics Data System (ADS)

    Yan, Jing; Wang, Jing; Liu, Hao; Bakenov, Zhumabay; Gosselink, Denise; Chen, P.

    2012-10-01

    A new aqueous rechargeable battery combining an intercalation cathode with a metal (first order electrode) anode has been developed. The concept is demonstrated using LiMn2O4 and zinc metal electrodes in an aqueous electrolyte containing two electrochemically active ions (Li+ and Zn2+). The battery operates at about 2 V and preliminarily tests show excellent cycling performance, with about 90% initial capacity retention over 1000 charge-discharge cycles. Use of cation-doped LiMn2O4 cathode further improves the cyclability of the system, which reaches 95% capacity retention after 4000 cycles. The energy density for a prototype battery, estimated at 50-80 Wh kg-1, is comparable or superior to commercial 2 V rechargeable batteries. The combined performance attributes of this new rechargeable aqueous battery indicate that it constitutes a viable alternative to commercial lead-acid system and for large scale energy storage application.

  6. Alternative Fuels and Hybrid Technology: A Classroom Activity Designed to Evaluate a Contemporary Problem

    ERIC Educational Resources Information Center

    Roy MacArthur, Amy H.; Copper, Christine L.

    2009-01-01

    As petroleum reserves are being depleted worldwide and energy costs are increasing, the use of alternative fuels is being more widely considered as a solution to the impending energy crisis. In this classroom activity students are presented with a real-world problem in which they must evaluate the properties and environmental impacts of a variety

  7. Alternative Fuels and Hybrid Technology: A Classroom Activity Designed to Evaluate a Contemporary Problem

    ERIC Educational Resources Information Center

    Roy MacArthur, Amy H.; Copper, Christine L.

    2009-01-01

    As petroleum reserves are being depleted worldwide and energy costs are increasing, the use of alternative fuels is being more widely considered as a solution to the impending energy crisis. In this classroom activity students are presented with a real-world problem in which they must evaluate the properties and environmental impacts of a variety…

  8. A rechargeable hydrogen battery based on Ru catalysis.

    PubMed

    Hsu, Shih-Fan; Rommel, Susanne; Eversfield, Philipp; Muller, Keven; Klemm, Elias; Thiel, Werner R; Plietker, Bernd

    2014-07-01

    Apart from energy generation, the storage and liberation of energy are among the major problems in establishing a sustainable energy supply chain. Herein we report the development of a rechargeable H2 battery which is based on the principle of the Ru-catalyzed hydrogenation of CO2 to formic acid (charging process) and the Ru-catalyzed decomposition of formic acid to CO2 and H2 (discharging process). Both processes are driven by the same catalyst at elevated temperature either under pressure (charging process) or pressure-free conditions (discharging process). Up to five charging-discharging cycles were performed without decrease of storage capacity. The resulting CO2/H2 mixture is free of CO and can be employed directly in fuel-cell technology. PMID:24803414

  9. The Exxon rechargeable cells

    NASA Astrophysics Data System (ADS)

    Malachesky, P. A.

    1980-04-01

    The design and performance of ambient temperature secondary cells based on the titanium disulfide cathode are discussed. These limited performance products were developed for microelectronic applications such as solar rechargeable watches and clocks which require low drain rate and do not require many deep cycles.

  10. Minimum fuel control of the planar circular restricted three-body problem

    NASA Astrophysics Data System (ADS)

    Caillau, J.-B.; Daoud, B.; Gergaud, J.

    2012-10-01

    The circular restricted three-body problem is considered to model the dynamics of an artificial body submitted to the attraction of two planets. Minimization of the fuel consumption of the spacecraft during the transfer, e.g. from the Earth to the Moon, is considered. In the light of the controllability results of Caillau and Daoud (SIAM J Control Optim, 2012), existence for this optimal control problem is discussed under simplifying assumptions. Thanks to Pontryagin maximum principle, the properties of fuel minimizing controls is detailed, revealing a bang-bang structure which is typical of L1-minimization problems. Because of the resulting non-smoothness of the Hamiltonian two-point boundary value problem, it is difficult to use shooting methods to compute numerical solutions (even with multiple shooting, as many switchings on the control occur when low thrusts are considered). To overcome these difficulties, two homotopies are introduced: One connects the investigated problem to the minimization of the L2-norm of the control, while the other introduces an interior penalization in the form of a logarithmic barrier. The combination of shooting with these continuation procedures allows to compute fuel optimal transfers for medium or low thrusts in the Earth-Moon system from a geostationary orbit, either towards the L 1 Lagrange point or towards a circular orbit around the Moon. To ensure local optimality of the computed trajectories, second order conditions are evaluated using conjugate point tests.

  11. Artificial recharge of groundwater and its role in water management

    USGS Publications Warehouse

    Kimrey, J.O.

    1989-01-01

    This paper summarizes and discusses the various aspects and methods of artificial recharge with particular emphasis on its uses and potential role in water management in the Arabian Gulf region. Artificial recharge occurs when man's activities cause more water to enter an aquifer, either under pumping or non-pumping conditions, than otherwise would enter the aquifer. Use of artificial recharge can be a practical means of dealing with problems of overdraft of groundwater. Methods of artificial recharge may be grouped under two broad types: (a) water spreading techniques, and (b) well-injection techniques. Successful use of artificial recharge requires a thorough knowledge of the physical and chemical characteristics of the aquifier system, and extensive onsite experimentation and tailoring of the artificial-recharge technique to fit the local or areal conditions. In general, water spreading techniques are less expensive than well injection and large quantities of water can be handled. Water spreading can also result in significant improvement in quality of recharge waters during infiltration and movement through the unsaturated zone and the receiving aquifer. In comparison, well-injection techniques are often used for emplacement of fresh recharge water into saline aquifer zones to form a manageable lens of fresher water, which may later be partially withdrawn for use or continue to be maintained as a barrier against salt-water encroachment. A major advantage in use of groundwater is its availability, on demand to wells, from a natural storage reservoir that is relatively safe from pollution and from damage by sabotage or other hostile action. However, fresh groundwater occurs only in limited quantities in most of the Arabian Gulf region; also, it is heavily overdrafted in many areas, and receives very little natural recharge. Good use could be made of artificial recharge by well injection in replenishing and managing aquifers in strategic locations if sources of freshwater could be made available for the artificial-recharge operations. ?? 1989.

  12. High Temperature Corrosion Problem of Boiler Components in presence of Sulfur and Alkali based Fuels

    NASA Astrophysics Data System (ADS)

    Ghosh, Debashis; Mitra, Swapan Kumar

    2011-04-01

    Material degradation and ageing is of particular concern for fossil fuel fired power plant components. New techniques/approaches have been explored in recent years for Residual Life assessment of aged components and material degradation due to different damage mechanism like creep, fatigue, corrosion and erosion etc. Apart from the creep, the high temperature corrosion problem in a fossil fuel fired boiler is a matter of great concern if the fuel contains sulfur, chlorine sodium, potassium and vanadium etc. This paper discusses the material degradation due to high temperature corrosion in different critical components of boiler like water wall, superheater and reheater tubes and also remedial measures to avoid the premature failure. This paper also high lights the Residual Life Assessment (RLA) methodology of the components based on high temperature fireside corrosion. of different critical components of boiler.

  13. Advanced Small Rechargeable Batteries

    NASA Technical Reports Server (NTRS)

    Halpert, Gerald

    1989-01-01

    Lithium-based units offer highest performance. Paper reviews status of advanced, small rechargeable batteries. Covers aqueous systems including lead/lead dioxide, cadmium/nickel oxide, hydrogen/nickel oxide, and zinc/nickel oxide, as well as nonaqueous systems. All based on lithium anodes, nonaqueous systems include solid-cathode cells (lithium/molybdenum disulfide, lithium/titanium disulfide, and lithium/vanadium oxide); liquid-cathode cells (lithium/sulfur dioxide cells); and new category, lithium/polymer cells.

  14. REMOTELY RECHARGEABLE EPD

    SciTech Connect

    Vrettos, N; Athneal Marzolf, A; Scott Bowser, S

    2007-11-13

    Radiation measurements inside the Contact Decon Maintenance Cell (CDMC) in the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) are required to determine stay times for personnel. A system to remotely recharge the transmitter of an Electronic Personnel Dosimeter (EPD) and bail assembly to transport the EPD within the CDMC was developed by the Savannah River National Laboratory (SRNL) to address this need.

  15. Rechargeable Magnesium Power Cells

    NASA Technical Reports Server (NTRS)

    Koch, Victor R.; Nanjundiah, Chenniah; Orsini, Michael

    1995-01-01

    Rechargeable power cells based on magnesium anodes developed as safer alternatives to high-energy-density cells like those based on lithium and sodium anodes. At cost of some reduction in energy density, magnesium-based cells safer because less susceptible to catastrophic meltdown followed by flames and venting of toxic fumes. Other advantages include ease of handling, machining, and disposal, and relatively low cost.

  16. A Comparison of Trajectory Optimization Methods for the Impulsive Minimum Fuel Rendezvous Problem

    NASA Technical Reports Server (NTRS)

    Hughes, Steven P.; Mailhe, Laurie M.; Guzman, Jose J.

    2002-01-01

    In this paper we present a comparison of optimization approaches to the minimum fuel rendezvous problem. Both indirect and direct methods are compared for a variety of test cases. The indirect approach is based on primer vector theory. The direct approaches are implemented numerically and include Sequential Quadratic Programming (SQP), Quasi-Newton, Simplex, Genetic Algorithms, and Simulated Annealing. Each method is applied to a variety of test cases including, circular to circular coplanar orbits, LEO to GEO, and orbit phasing in highly elliptic orbits. We also compare different constrained optimization routines on complex orbit rendezvous problems with complicated, highly nonlinear constraints.

  17. Rechargeable lead-acid batteries.

    PubMed

    1990-09-01

    Batteries used in medical equipment, like their counterparts in consumer products, attract little attention until they fail to function effectively. In some applications, such as in emergency medical devices, battery failure can have fatal consequences. While modern batteries are usually quite reliable, ECRI has received 53 written problem reports and countless verbal reports or questions related to battery problems in hospitals during the past five years. This large number of reports is due, at least in part, to the enormous quality of batteries used to operate or provide backup power in contemporary hospital equipment. As part of an ongoing evaluation of rehabilitation assistive equipment, ECRI has been studying the performance of 12 V rechargeable deep-cycle lead-acid batteries used in powered wheelchairs. During the course of this evaluation, it has become apparent that many professionals, both clinical and industrial, regard batteries as "black box" devices and know little about proper care and maintenance--and even less about battery selection and purchase. Because equipment performance and reliability can be strongly influenced by different battery models, an understanding of battery characteristics and how they affect performance is essential when selecting and purchasing batteries. The types of rechargeable batteries used most commonly in hospitals are lead-acid and nickel-cadmium (nicad), which we compare below; however, the guidance we provide in this article focuses on lead-acid batteries. While the examples given are for high-capacity 12 V deep-cycle batteries, similar analyses can be applied to smaller lead-acid batteries of different voltages. PMID:2211174

  18. Recharge into a shingle beach

    NASA Astrophysics Data System (ADS)

    Keating, T.

    1984-04-01

    Traditionally, groundwater recharge in the U.K. has been calculated by the Penman method on a monthly basis, using values of potential evaporation derived from averaged meteorological data and monthly totals of rainfall. Recent work by K.W.F. Howard and J.W. Lloyd has shown that these monthly totals considerably underestimate recharge calculated over shorter time periods and they suggested that 1-day, or at worst, 10-day intervals should be used. In this paper field experiments to measure recharge into a shingle beach are reported. These experiments were made with a lysimeter over a 6-yr. period and have shown that recharge into the shingle occurs whenever significant precipitation occurs, even during the summer months. The Penman model is shown to be unrealistic for estimating recharge into such a beach and an alternative model for calculating recharge is proposed. This model is shown to yield good results.

  19. Application of wavelet scaling function expansion continuous-energy resonance calculation method to MOX fuel problem

    SciTech Connect

    Yang, W.; Wu, H.; Cao, L.

    2012-07-01

    More and more MOX fuels are used in all over the world in the past several decades. Compared with UO{sub 2} fuel, it contains some new features. For example, the neutron spectrum is harder and more resonance interference effects within the resonance energy range are introduced because of more resonant nuclides contained in the MOX fuel. In this paper, the wavelets scaling function expansion method is applied to study the resonance behavior of plutonium isotopes within MOX fuel. Wavelets scaling function expansion continuous-energy self-shielding method is developed recently. It has been validated and verified by comparison to Monte Carlo calculations. In this method, the continuous-energy cross-sections are utilized within resonance energy, which means that it's capable to solve problems with serious resonance interference effects without iteration calculations. Therefore, this method adapts to treat the MOX fuel resonance calculation problem natively. Furthermore, plutonium isotopes have fierce oscillations of total cross-section within thermal energy range, especially for {sup 240}Pu and {sup 242}Pu. To take thermal resonance effect of plutonium isotopes into consideration the wavelet scaling function expansion continuous-energy resonance calculation code WAVERESON is enhanced by applying the free gas scattering kernel to obtain the continuous-energy scattering source within thermal energy range (2.1 eV to 4.0 eV) contrasting against the resonance energy range in which the elastic scattering kernel is utilized. Finally, all of the calculation results of WAVERESON are compared with MCNP calculation. (authors)

  20. Fuzzy-decision-making problems of fuel ethanol production using a genetically engineered yeast

    SciTech Connect

    Wang, F.S.; Jing, C.H.; Tsao, G.T.

    1998-08-01

    A fuzzy-decision-making procedure is applied to find the optimal feed policy of a fed-batch fermentation process for fuel ethanol production using a genetically engineered Saccharomyces yeast 1400 (pLNH33). The policy consisted of feed flow rate, feed concentration, and fermentation time. The recombinant yeast 1400 (pLNH33) can utilize glucose and xylose simultaneously to produce ethanol. However, the parent yeast utilizes glucose only. A partially selective model is used to describe the kinetic behavior of the process. In this study, this partially selective fermentation process is formulated as a general multiple-objective optimal control problem. By using an assigned membership function for each of the objectives, the general multiple-objective optimization problem can be converted into a maximizing decision problem. In order to obtain a global solution, a hybrid method of differential evolution is introduced to solve the maximizing decision problem. A simple guideline is introduced in the interactive programming procedures to find a satisfactory solution to the general multiple-objective optimization problem.

  1. Ceramic Lithium Ion Conductor to Solve the Anode Coking Problem of Practical Solid Oxide Fuel Cells.

    PubMed

    Wang, Wei; Wang, Feng; Chen, Yubo; Qu, Jifa; Tadé, Moses O; Shao, Zongping

    2015-09-01

    For practical solid oxide fuel cells (SOFCs) operated on hydrocarbon fuels, the facile coke formation over Ni-based anodes has become a key factor that limits their widespread application. Modification of the anodes with basic elements may effectively improve their coking resistance in the short term; however, the easy loss of basic elements by thermal evaporation at high temperatures is a new emerging problem. Herein, we propose a new design to develop coking-resistant and stable SOFCs using Li(+) -conducting Li0.33 La0.56 TiO3 (LLTO) as an anode component. In the Ni/LLTO composite, any loss of surface lithium can be efficiently compensated by lithium diffused from the LLTO bulk under operation. Therefore, the SOFC with the Ni/LLTO anode catalyst layer yields excellent power outputs and operational stability. Our results suggest that the simple adoption of a Li(+) conductor as a modifier for Ni-based anodes is a practical and easy way to solve the coking problem of SOFCs that operate on hydrocarbons. PMID:25925556

  2. FLUIDIC: Metal Air Recharged

    SciTech Connect

    Friesen, Cody

    2014-03-07

    Fluidic, with the help of ARPA-E funding, has developed and deployed the world's first proven high cycle life metal air battery. Metal air technology, often used in smaller scale devices like hearing aids, has the lowest cost per electron of any rechargeable battery storage in existence. Deploying these batteries for grid reliability is competitive with pumped hydro installations while having the advantages of a small footprint. Fluidic's battery technology allows utilities and other end users to store intermittent energy generated from solar and wind, as well as maintain reliable electrical delivery during power outages. The batteries are manufactured in the US and currently deployed to customers in emerging markets for cell tower reliability. As they continue to add customers, they've gained experience and real world data that will soon be leveraged for US grid reliability.

  3. FLUIDIC: Metal Air Recharged

    ScienceCinema

    Friesen, Cody

    2014-04-02

    Fluidic, with the help of ARPA-E funding, has developed and deployed the world's first proven high cycle life metal air battery. Metal air technology, often used in smaller scale devices like hearing aids, has the lowest cost per electron of any rechargeable battery storage in existence. Deploying these batteries for grid reliability is competitive with pumped hydro installations while having the advantages of a small footprint. Fluidic's battery technology allows utilities and other end users to store intermittent energy generated from solar and wind, as well as maintain reliable electrical delivery during power outages. The batteries are manufactured in the US and currently deployed to customers in emerging markets for cell tower reliability. As they continue to add customers, they've gained experience and real world data that will soon be leveraged for US grid reliability.

  4. Nanostructured cathode materials for rechargeable lithium batteries

    NASA Astrophysics Data System (ADS)

    Myung, Seung-Taek; Amine, Khalil; Sun, Yang-Kook

    2015-06-01

    The prospect of drastic climate change and the ceaseless fluctuation of fossil fuel prices provide motivation to reduce the use of fossil fuels and to find new energy conversion and storage systems that are able to limit carbon dioxide generation. Among known systems, lithium-ion batteries are recognized as the most appropriate energy storage system because of their high energy density and thus space saving in applications. Introduction of nanotechnology to electrode material is beneficial to improve the resulting electrode performances such as capacity, its retention, and rate capability. The nanostructure is highly available not only when used alone but also is more highlighted when harmonized in forms of core-shell structure and composites with carbon nanotubes, graphene or reduced graphene oxides. This review covers syntheses and electrochemical properties of nanoscale, nanosized, and nanostructured cathode materials for rechargeable lithium batteries.

  5. Pulverized fuel ash products solve the sewage sludge problems of the wastewater industry

    SciTech Connect

    Dirk, G.

    1996-12-31

    Sewage sludge recycling has become one of the predominant problems of the water industry. Not all types of sewage sludges are able to be recycled to farm land or into composting processes. Pulverized fuel ash is used as a major ingredient in a product called Rhenipal which is used to stabilize sewage sludge for recycling into a material for land reclamation, as a soil conditioner, as cover material for landfill and as a landfill engineering material. This article deals with the results achieved when applying rhenipal in a post-stabilization process to prepare landfill engineering material. The process is currently developed further and can be operated in a pre-stabilization mode, which will further improve the economical results shown for the post-stabilization method in this paper.

  6. Waste fuel handling system design: How to avoid or solve flow problems

    SciTech Connect

    Purutyan, H.; Pittenger, B.H.; Stuart-Dick, D.

    1994-12-31

    The number of power plants utilizing waste products as fuel has increased due to a number of factors. First, growing environmental concerns have provided a thrust for utilizing waste products, such as culm, gob, bio-mass, chopped tires, etc., rather than stockpiling them. At the same time, advances in combustion technology, i.e., high efficiencies and cleaner combustion have made energy extraction economically viable. A second driving economic factor has been incentives for co-generation plants provided by the Public Utilities Regulatory Policies Act of 1978. In plants and processes involving solids handling, the proper operation of the solids handling systems is often one of the most crucial elements in preventing plant startup delays, reduced plant efficiency, and equipment downtime. The Rand Corporation conducted a six-year study of 40 solids processing plants in the U.S. and Canada. Their findings reveal that 80% of these plants experience solids handling problems. This study also found that these plants were slow in coming up-to-speed, with an average startup time for some types of plants approaching 18 months. Once startup begins, poor performance continues to plague these operations with performance between 40% and 50% of design. While the focus of this survey was not exclusively power plants, parallels can easily be drawn to waste-to-energy plants since the fuel is inherently variable and often difficult to handle. Problems with material handling systems can translate into big losses as heavy penalties may be imposed for startup delays and for not meeting on-line requirements.

  7. Numerical Tests for the Problem of U-Pu Fuel Burnup in Fuel Rod and Polycell Models Using the MCNP Code

    NASA Astrophysics Data System (ADS)

    Muratov, V. G.; Lopatkin, A. V.

    An important aspect in the verification of the engineering techniques used in the safety analysis of MOX-fuelled reactors, is the preparation of test calculations to determine nuclide composition variations under irradiation and analysis of burnup problem errors resulting from various factors, such as, for instance, the effect of nuclear data uncertainties on nuclide concentration calculations. So far, no universally recognized tests have been devised. A calculation technique has been developed for solving the problem using the up-to-date calculation tools and the latest versions of nuclear libraries. Initially, in 1997, a code was drawn up in an effort under ISTC Project No. 116 to calculate the burnup in one VVER-1000 fuel rod, using the MCNP Code. Later on, the authors developed a computation technique which allows calculating fuel burnup in models of a fuel rod, or a fuel assembly, or the whole reactor. It became possible to apply it to fuel burnup in all types of nuclear reactors and subcritical blankets.

  8. Functional materials for rechargeable batteries.

    PubMed

    Cheng, Fangyi; Liang, Jing; Tao, Zhanliang; Chen, Jun

    2011-04-19

    There is an ever-growing demand for rechargeable batteries with reversible and efficient electrochemical energy storage and conversion. Rechargeable batteries cover applications in many fields, which include portable electronic consumer devices, electric vehicles, and large-scale electricity storage in smart or intelligent grids. The performance of rechargeable batteries depends essentially on the thermodynamics and kinetics of the electrochemical reactions involved in the components (i.e., the anode, cathode, electrolyte, and separator) of the cells. During the past decade, extensive efforts have been dedicated to developing advanced batteries with large capacity, high energy and power density, high safety, long cycle life, fast response, and low cost. Here, recent progress in functional materials applied in the currently prevailing rechargeable lithium-ion, nickel-metal hydride, lead acid, vanadium redox flow, and sodium-sulfur batteries is reviewed. The focus is on research activities toward the ionic, atomic, or molecular diffusion and transport; electron transfer; surface/interface structure optimization; the regulation of the electrochemical reactions; and the key materials and devices for rechargeable batteries. PMID:21394791

  9. GPU Based General-Purpose Parallel computing to Solve Nuclear Reactor In-Core fuel Management Design and Operation Problem

    SciTech Connect

    Prayudhatama, D.; Waris, A.; Kurniasih, N.; Kurniadi, R.

    2010-06-22

    In-core fuel management study is a crucial activity in nuclear power plant design and operation. Its common problem is to find an optimum arrangement of fuel assemblies inside the reactor core. Main objective for this activity is to reduce the cost of generating electricity, which can be done by altering several physical properties of the nuclear reactor without violating any of the constraints imposed by operational and safety considerations. This research try to address the problem of nuclear fuel arrangement problem, which is, leads to the multi-objective optimization problem. However, the calculation of the reactor core physical properties itself is a heavy computation, which became obstacle in solving the optimization problem by using genetic algorithm optimization.This research tends to address that problem by using the emerging General Purpose Computation on Graphics Processing Units (GPGPU) techniques implemented by C language for CUDA (Compute Unified Device Architecture) parallel programming. By using this parallel programming technique, we develop parallelized nuclear reactor fitness calculation, which is involving numerical finite difference computation. This paper describes current prototype of the parallel algorithm code we have developed on CUDA, that performs one hundreds finite difference calculation for nuclear reactor fitness evaluation in parallel by using GPU G9 Hardware Series developed by NVIDIA.

  10. GPU Based General-Purpose Parallel computing to Solve Nuclear Reactor In-Core fuel Management Design and Operation Problem

    NASA Astrophysics Data System (ADS)

    Prayudhatama, D.; Waris, A.; Kurniasih, N.; Kurniadi, R.

    2010-06-01

    In-core fuel management study is a crucial activity in nuclear power plant design and operation. Its common problem is to find an optimum arrangement of fuel assemblies inside the reactor core. Main objective for this activity is to reduce the cost of generating electricity, which can be done by altering several physical properties of the nuclear reactor without violating any of the constraints imposed by operational and safety considerations. This research try to address the problem of nuclear fuel arrangement problem, which is, leads to the multi-objective optimization problem. However, the calculation of the reactor core physical properties itself is a heavy computation, which became obstacle in solving the optimization problem by using genetic algorithm optimization. This research tends to address that problem by using the emerging General Purpose Computation on Graphics Processing Units (GPGPU) techniques implemented by C language for CUDA (Compute Unified Device Architecture) parallel programming. By using this parallel programming technique, we develop parallelized nuclear reactor fitness calculation, which is involving numerical finite difference computation. This paper describes current prototype of the parallel algorithm code we have developed on CUDA, that performs one hundreds finite difference calculation for nuclear reactor fitness evaluation in parallel by using GPU G9 Hardware Series developed by NVIDIA.

  11. Promoting the Market for Plug-in Hybrid and Battery Electric Vehicles: Role of Recharge Availability

    SciTech Connect

    Lin, Zhenhong; Greene, David L

    2012-01-01

    Much recent attention has been drawn to providing adequate recharge availability as a means to promote the battery electric vehicle (BEV) and plug-in hybrid electric vehicle (PHEV) market. The possible role of improved recharge availability in developing the BEV-PHEV market and the priorities that different charging options should receive from the government require better understanding. This study reviews the charging issue and conceptualizes it into three interactions between the charge network and the travel network. With travel data from 3,755 drivers in the National Household Travel Survey, this paper estimates the distribution among U.S. consumers of (a) PHEV fuel-saving benefits by different recharge availability improvements, (b) range anxiety by different BEV ranges, and (c) willingness to pay for workplace and public charging in addition to home recharging. With the Oak Ridge National Laboratory MA3T model, the impact of three recharge improvements is quantified by the resulting increase in BEV-PHEV sales. Compared with workplace and public recharging improvements, home recharging improvement appears to have a greater impact on BEV-PHEV sales. The impact of improved recharging availability is shown to be amplified by a faster reduction in battery cost.

  12. Low NPSH process pumps solve instability problems in fuel-grade ethanol plant

    SciTech Connect

    Andersen, R.B.; Gaines, A.

    1984-12-01

    South Point Ethanol, one of the nation's largest producers of denatured ethyl alcohol for blending with motor fuels, encountered severe instability problems with certain pumps when the plant in South Point, Ohio went on-stream in September 1982. The ethanol is produced by fermenting the starch in cooked corn and other grains. Two 4 x 3'' centrifugal pumps with 13'' casing and 11'' impellers were originally installed to transfer the 185/sup 0/F slurry of cooked grain, or mash, through a series of coolers and into the fermenters. The single stage pumps were driven by 3600 rpm motors to provide flow rates to 600 gpm and up to 480' tdh, but developed instability problems due to the high tip speed of the 11'' impellers. The pumps transferring the degassed beer were replaced with pumps which feature a semi-open reverse vane impeller that is specifically designed to minimize stuffing box pressure and provide superior performance when operating at very low net positive suction head (NPSH) with volatile and near-boiling fluids. Two 6 x 4 x 10'' pumps with the reverse vane, low NPSH impeller were purchased to replace the 4 x 3 x 13'' mash transfer pumps that had to be overhauled about once a week. The new pumps were installed on the same bases and are driven by the original 3600 rpm electric motors. The four pumps have provided smooth, trouble-free transfer of the hot mash and degassed beer for over a year without any replacement parts or other than routine maintenance. The plant currently operates about 40 of the pumps in sizes from 1 1/2 x 1 x 6'' to 10 x 8 x 16'' to provide flow rates to 825 gpm and up to 490' tdh in various applications.

  13. A Comparison of Trajectory Optimization Methods for the Impulsive Minimum Fuel Rendezvous Problem

    NASA Technical Reports Server (NTRS)

    Hughes, Steven P.; Mailhe, Laurie M.; Guzman, Jose J.

    2003-01-01

    In this paper we present, a comparison of trajectory optimization approaches for the minimum fuel rendezvous problem. Both indirect and direct methods are compared for a variety of test cases. The indirect approach is based on primer vector theory. The direct approaches are implemented numerically and include Sequential Quadratic Programming (SQP). Quasi- Newton and Nelder-Meade Simplex. Several cost function parameterizations are considered for the direct approach. We choose one direct approach that appears to be the most flexible. Both the direct and indirect methods are applied to a variety of test cases which are chosen to demonstrate the performance of each method in different flight regimes. The first test case is a simple circular-to-circular coplanar rendezvous. The second test case is an elliptic-to-elliptic line of apsides rotation. The final test case is an orbit phasing maneuver sequence in a highly elliptic orbit. For each test case we present a comparison of the performance of all methods we consider in this paper.

  14. Fuel cells provide a revenue-generating solution to power quality problems

    SciTech Connect

    King, J.M. Jr.

    1996-03-01

    Electric power quality and reliability are becoming increasingly important as computers and microprocessors assume a larger role in commercial, health care and industrial buildings and processes. At the same time, constraints on transmission and distribution of power from central stations are making local areas vulnerable to low voltage, load addition limitations, power quality and power reliability problems. Many customers currently utilize some form of premium power in the form of standby generators and/or UPS systems. These include customers where continuous power is required because of health and safety or security reasons (hospitals, nursing homes, places of public assembly, air traffic control, military installations, telecommunications, etc.) These also include customers with industrial or commercial processes which can`t tolerance an interruption of power because of product loss or equipment damage. The paper discusses the use of the PC25 fuel cell power plant for backup and parallel power supplies for critical industrial applications. Several PC25 installations are described: the use of propane in a PC25; the use by rural cooperatives; and a demonstration of PC25 technology using landfill gas.

  15. Reusable Energy and Power Sources: Rechargeable Batteries

    ERIC Educational Resources Information Center

    Hsiung, Steve C.; Ritz, John M.

    2007-01-01

    Rechargeable batteries are very popular within consumer electronics. If one uses a cell phone or portable electric tool, she/he understands the need to have a reliable product and the need to remember to use the recharging systems that follow a cycle of charge/discharge. Rechargeable batteries are being called "green" energy sources. They are a…

  16. Choosing appropriate techniques for quantifying groundwater recharge

    USGS Publications Warehouse

    Scanlon, B.R.; Healy, R.W.; Cook, P.G.

    2002-01-01

    Various techniques are available to quantify recharge; however, choosing appropriate techniques is often difficult. Important considerations in choosing a technique include space/time scales, range, and reliability of recharge estimates based on different techniques; other factors may limit the application of particular techniques. The goal of the recharge study is important because it may dictate the required space/time scales of the recharge estimates. Typical study goals include water-resource evaluation, which requires information on recharge over large spatial scales and on decadal time scales; and evaluation of aquifer vulnerability to contamination, which requires detailed information on spatial variability and preferential flow. The range of recharge rates that can be estimated using different approaches should be matched to expected recharge rates at a site. The reliability of recharge estimates using different techniques is variable. Techniques based on surface-water and unsaturated-zone data provide estimates of potential recharge, whereas those based on groundwater data generally provide estimates of actual recharge. Uncertainties in each approach to estimating recharge underscore the need for application of multiple techniques to increase reliability of recharge estimates.

  17. Reusable Energy and Power Sources: Rechargeable Batteries

    ERIC Educational Resources Information Center

    Hsiung, Steve C.; Ritz, John M.

    2007-01-01

    Rechargeable batteries are very popular within consumer electronics. If one uses a cell phone or portable electric tool, she/he understands the need to have a reliable product and the need to remember to use the recharging systems that follow a cycle of charge/discharge. Rechargeable batteries are being called "green" energy sources. They are a

  18. Rechargeable nickel-zinc batteries

    NASA Technical Reports Server (NTRS)

    Soltis, D. G.

    1977-01-01

    Device proves superiority in having two and one half to three times the energy content of popular lead-zinc or nickel-cadmium batteries. Application to electric utility vehicles improved acceleration rate and nearly doubled driving range between rechargings. Unit contributes substantially toward realization of practical urban electrical automobiles.

  19. The pronounced seasonality of global groundwater recharge

    NASA Astrophysics Data System (ADS)

    Jasechko, Scott; Birks, S. Jean; Gleeson, Tom; Wada, Yoshihide; Fawcett, Peter J.; Sharp, Zachary D.; McDonnell, Jeffrey J.; Welker, Jeffrey M.

    2014-11-01

    Groundwater recharged by meteoric water supports human life by providing two billion people with drinking water and by supplying 40% of cropland irrigation. While annual groundwater recharge rates are reported in many studies, fewer studies have explicitly quantified intra-annual (i.e., seasonal) differences in groundwater recharge. Understanding seasonal differences in the fraction of precipitation that recharges aquifers is important for predicting annual recharge groundwater rates under changing seasonal precipitation and evapotranspiration regimes in a warming climate, for accurately interpreting isotopic proxies in paleoclimate records, and for understanding linkages between ecosystem productivity and groundwater recharge. Here we determine seasonal differences in the groundwater recharge ratio, defined here as the ratio of groundwater recharge to precipitation, at 54 globally distributed locations on the basis of 18O/16O and 2H/1H ratios in precipitation and groundwater. Our analysis shows that arid and temperate climates have wintertime groundwater recharge ratios that are consistently higher than summertime groundwater recharge ratios, while tropical groundwater recharge ratios are at a maximum during the wet season. The isotope-based recharge ratio seasonality is consistent with monthly outputs from a global hydrological model (PCR-GLOBWB) for most, but not all locations. The pronounced seasonality in groundwater recharge ratios shown in this study signifies that, from the point of view of predicting future groundwater recharge rates, a unit change in winter (temperate and arid regions) or wet season (tropics) precipitation will result in a greater change to the annual groundwater recharge rate than the same unit change to summer or dry season precipitation.

  20. Prototype systems for rechargeable magnesium batteries.

    PubMed

    Aurbach, D; Lu, Z; Schechter, A; Gofer, Y; Gizbar, H; Turgeman, R; Cohen, Y; Moshkovich, M; Levi, E

    2000-10-12

    The thermodynamic properties of magnesium make it a natural choice for use as an anode material in rechargeable batteries, because it may provide a considerably higher energy density than the commonly used lead-acid and nickel-cadmium systems. Moreover, in contrast to lead and cadmium, magnesium is inexpensive, environmentally friendly and safe to handle. But the development of Mg batteries has been hindered by two problems. First, owing to the chemical activity of Mg, only solutions that neither donate nor accept protons are suitable as electrolytes; but most of these solutions allow the growth of passivating surface films, which inhibit any electrochemical reaction. Second, the choice of cathode materials has been limited by the difficulty of intercalating Mg ions in many hosts. Following previous studies of the electrochemistry of Mg electrodes in various non-aqueous solutions, and of a variety of intercalation electrodes, we have now developed rechargeable Mg battery systems that show promise for applications. The systems comprise electrolyte solutions based on Mg organohaloaluminate salts, and Mg(x)Mo3S4 cathodes, into which Mg ions can be intercalated reversibly, and with relatively fast kinetics. We expect that further improvements in the energy density will make these batteries a viable alternative to existing systems. PMID:11048714

  1. A Parallel Multi-Domain Solution Methodology Applied to Nonlinear Thermal Transport Problems in Nuclear Fuel Pins

    DOE PAGESBeta

    Philip, Bobby; Berrill, Mark A; Allu, Srikanth; Hamilton, Steven P; Sampath, Rahul S; Clarno, Kevin T; Dilts, Gary

    2015-01-01

    This paper describes an efficient and nonlinearly consistent parallel solution methodology for solving coupled nonlinear thermal transport problems that occur in nuclear reactor applications over hundreds of individual 3D physical subdomains. Efficiency is obtained by leveraging knowledge of the physical domains, the physics on individual domains, and the couplings between them for preconditioning within a Jacobian Free Newton Krylov method. Details of the computational infrastructure that enabled this work, namely the open source Advanced Multi-Physics (AMP) package developed by the authors are described. Details of verification and validation experiments, and parallel performance analysis in weak and strong scaling studies demonstratingmore » the achieved efficiency of the algorithm are presented. Furthermore, numerical experiments demonstrate that the preconditioner developed is independent of the number of fuel subdomains in a fuel rod, which is particularly important when simulating different types of fuel rods. Finally, we demonstrate the power of the coupling methodology by considering problems with couplings between surface and volume physics and coupling of nonlinear thermal transport in fuel rods to an external radiation transport code.« less

  2. A Parallel Multi-Domain Solution Methodology Applied to Nonlinear Thermal Transport Problems in Nuclear Fuel Pins

    SciTech Connect

    Philip, Bobby; Berrill, Mark A; Allu, Srikanth; Hamilton, Steven P; Clarno, Kevin T; Dilts, Gary

    2014-08-01

    This paper describes an efficient and nonlinearly consistent parallel solution methodology for solving coupled nonlinear thermal transport problems that occur in nuclear reactor applications over hundreds of individual 3D physical subdomains. Efficiency is obtained by leveraging knowledge of the physical domains, the physics on individual domains, and the couplings between them for preconditioning within a Jacobian Free Newton Krylov method. Details of the computational infrastructure that enabled this work, namely the open source Advanced Multi-Physics (AMP) package developed by the authors is described. Details of verification and validation experiments, and parallel performance analysis in weak and strong scaling studies demonstrating the achieved efficiency of the algorithm are presented. Furthermore, numerical experiments demonstrate that the preconditioner developed is independent of the number of fuel subdomains in a fuel rod, which is particularly important when simulating different types of fuel rods. Finally, we demonstrate the power of the coupling methodology by considering problems with couplings between surface and volume physics and coupling of nonlinear thermal transport in fuel rods to an external radiation transport code.

  3. A Parallel Multi-Domain Solution Methodology Applied to Nonlinear Thermal Transport Problems in Nuclear Fuel Pins

    SciTech Connect

    Philip, Bobby; Berrill, Mark A; Allu, Srikanth; Hamilton, Steven P; Sampath, Rahul S; Clarno, Kevin T; Dilts, Gary

    2015-01-01

    This paper describes an efficient and nonlinearly consistent parallel solution methodology for solving coupled nonlinear thermal transport problems that occur in nuclear reactor applications over hundreds of individual 3D physical subdomains. Efficiency is obtained by leveraging knowledge of the physical domains, the physics on individual domains, and the couplings between them for preconditioning within a Jacobian Free Newton Krylov method. Details of the computational infrastructure that enabled this work, namely the open source Advanced Multi-Physics (AMP) package developed by the authors are described. Details of verification and validation experiments, and parallel performance analysis in weak and strong scaling studies demonstrating the achieved efficiency of the algorithm are presented. Furthermore, numerical experiments demonstrate that the preconditioner developed is independent of the number of fuel subdomains in a fuel rod, which is particularly important when simulating different types of fuel rods. Finally, we demonstrate the power of the coupling methodology by considering problems with couplings between surface and volume physics and coupling of nonlinear thermal transport in fuel rods to an external radiation transport code.

  4. A parallel multi-domain solution methodology applied to nonlinear thermal transport problems in nuclear fuel pins

    NASA Astrophysics Data System (ADS)

    Philip, Bobby; Berrill, Mark A.; Allu, Srikanth; Hamilton, Steven P.; Sampath, Rahul S.; Clarno, Kevin T.; Dilts, Gary A.

    2015-04-01

    This paper describes an efficient and nonlinearly consistent parallel solution methodology for solving coupled nonlinear thermal transport problems that occur in nuclear reactor applications over hundreds of individual 3D physical subdomains. Efficiency is obtained by leveraging knowledge of the physical domains, the physics on individual domains, and the couplings between them for preconditioning within a Jacobian Free Newton Krylov method. Details of the computational infrastructure that enabled this work, namely the open source Advanced Multi-Physics (AMP) package developed by the authors is described. Details of verification and validation experiments, and parallel performance analysis in weak and strong scaling studies demonstrating the achieved efficiency of the algorithm are presented. Furthermore, numerical experiments demonstrate that the preconditioner developed is independent of the number of fuel subdomains in a fuel rod, which is particularly important when simulating different types of fuel rods. Finally, we demonstrate the power of the coupling methodology by considering problems with couplings between surface and volume physics and coupling of nonlinear thermal transport in fuel rods to an external radiation transport code.

  5. Problems in developing bimodal space power and propulsion system fuel element

    SciTech Connect

    Nikolaev, Yu. V.; Gontar, A. S.; Zaznoba, V. A.; Parshin, N. Ya.; Ponomarev-Stepnoi, N. N.; Usov, V. A.

    1997-01-10

    The paper discusses design of a space nuclear power and propulsion system fuel element (PPFE) developed on the basis of an enhanced single-cell thermionic fuel element (TFE) of the 'TOPAZ-2' thermionic converter-reactor (TCR), and presents the PPFE performance for propulsion and power modes of operation. The choice of UC-TaC fuel composition is substantiated. Data on hydrogen effect on the PPFE output voltage are presented, design solutions are considered that allow to restrict hydrogen supply to an interelectrode gap (IEG). Long-term geometric stability of an emitter assembly is supported by calculated data.

  6. Nanomaterials for rechargeable lithium batteries.

    PubMed

    Bruce, Peter G; Scrosati, Bruno; Tarascon, Jean-Marie

    2008-01-01

    Energy storage is more important today than at any time in human history. Future generations of rechargeable lithium batteries are required to power portable electronic devices (cellphones, laptop computers etc.), store electricity from renewable sources, and as a vital component in new hybrid electric vehicles. To achieve the increase in energy and power density essential to meet the future challenges of energy storage, new materials chemistry, and especially new nanomaterials chemistry, is essential. We must find ways of synthesizing new nanomaterials with new properties or combinations of properties, for use as electrodes and electrolytes in lithium batteries. Herein we review some of the recent scientific advances in nanomaterials, and especially in nanostructured materials, for rechargeable lithium-ion batteries. PMID:18338357

  7. Recharge Data for Hawaii Island

    SciTech Connect

    Nicole Lautze

    2015-01-01

    Recharge data for Hawaii Island in shapefile format. The data are from the following sources: Whittier, R.B and A.I. El-Kadi. 2014. Human Health and Environmental Risk Ranking of On-Site Sewage Disposal systems for the Hawaiian Islands of Kauai, Molokai, Maui, and Hawaii – Final, Prepared for Hawaii Dept. of Health, Safe Drinking Water Branch by the University of Hawaii, Dept. of Geology and Geophysics. Oki, D. S. 1999. Geohydrology and Numerical Simulation of the Ground-Water Flow System of Kona, Island of Hawaii. U.S. Water-Resources Investigation Report: 99-4073. Oki, D. S. 2002. Reassessment of Ground-water Recharge and Simulated Ground-Water Availability for the Hawi Area of North Kohala, Hawaii. U.S. Geological Survey Water-Resources Investigation report 02-4006.

  8. Electrically rechargeable REDOX flow cell

    NASA Technical Reports Server (NTRS)

    Thaller, L. H. (Inventor)

    1976-01-01

    A bulk energy storage system is designed with an electrically rechargeable reduction-oxidation (REDOX) cell divided into two compartments by a membrane, each compartment containing an electrode. An anode fluid is directed through the first compartment at the same time that a cathode fluid is directed through the second compartment. Means are provided for circulating the anode and cathode fluids, and the electrodes are connected to an intermittent or non-continuous electrical source, which when operating, supplies current to a load as well as to the cell to recharge it. Ancillary circuitry is provided for disconnecting the intermittent source from the cell at prescribed times and for circulating the anode and cathode fluids according to desired parameters and conditions.

  9. Rechargeable metal hydrides for spacecraft application

    NASA Technical Reports Server (NTRS)

    Perry, J. L.

    1988-01-01

    Storing hydrogen on board the Space Station presents both safety and logistics problems. Conventional storage using pressurized bottles requires large masses, pressures, and volumes to handle the hydrogen to be used in experiments in the U.S. Laboratory Module and residual hydrogen generated by the ECLSS. Rechargeable metal hydrides may be competitive with conventional storage techniques. The basic theory of hydride behavior is presented and the engineering properties of LaNi5 are discussed to gain a clear understanding of the potential of metal hydrides for handling spacecraft hydrogen resources. Applications to Space Station and the safety of metal hydrides are presented and compared to conventional hydride storage. This comparison indicates that metal hydrides may be safer and require lower pressures, less volume, and less mass to store an equivalent mass of hydrogen.

  10. Iron-Air Rechargeable Battery

    NASA Technical Reports Server (NTRS)

    Narayan, Sri R. (Inventor); Prakash, G.K. Surya (Inventor); Kindler, Andrew (Inventor)

    2014-01-01

    Embodiments include an iron-air rechargeable battery having a composite electrode including an iron electrode and a hydrogen electrode integrated therewith. An air electrode is spaced from the iron electrode and an electrolyte is provided in contact with the air electrode and the iron electrodes. Various additives and catalysts are disclosed with respect to the iron electrode, air electrode, and electrolyte for increasing battery efficiency and cycle life.

  11. Survey of rechargeable battery technology

    SciTech Connect

    Not Available

    1993-07-01

    We have reviewed rechargeable battery technology options for a specialized application in unmanned high altitude aircraft. Consideration was given to all rechargeable battery technologies that are available commercially or might be available in the foreseeable future. The LLNL application was found to impose very demanding performance requirements which cannot be met by existing commercially available battery technologies. The most demanding requirement is for high energy density. The technology that comes closest to providing the LLNL requirements is silver-zinc, although the technology exhibits significant shortfalls in energy density, charge rate capability and cyclability. There is no battery technology available ``off-the-shelf` today that can satisfy the LLNL performance requirements. All rechargeable battery technologies with the possibility of approaching/meeting the energy density requirements were reviewed. Vendor interviews were carried out for all relevant technologies. A large number of rechargeable battery systems have been developed over the years, though a much smaller number have achieved commercial success and general availability. The theoretical energy densities for these systems are summarized. It should be noted that a generally useful ``rule-of-thumb`` is that the ratio of packaged to theoretical energy density has proven to be less than 30%, and generally less than 25%. Data developed for this project confirm the usefulness of the general rule. However, data shown for the silver-zinc (AgZn) system show a greater conversion of theoretical to practical energy density than would be expected due to the very large cell sizes considered and the unusually high density of the active materials.

  12. Charge Characteristics of Rechargeable Batteries

    NASA Astrophysics Data System (ADS)

    Maheswaranathan, Ponn; Kelly, Cormac

    2014-03-01

    Rechargeable batteries play important role in technologies today and they are critical for the future. They are used in many electronic devices and their capabilities need to keep up with the accelerated pace of technology. Efficient energy capture and storage is necessary for the future rechargeable batteries. Charging and discharging characteristics of three popular commercially available re-chargeable batteries (NiCd, NiMH, and Li Ion) are investigated and compared with regular alkaline batteries. Pasco's 850 interface and their voltage & current sensors are used to monitor the current through and the potential difference across the battery. The discharge current and voltage stayed fairly constant until the end, with a slightly larger drop in voltage than current, which is more pronounced in the alkaline batteries. After 25 charge/discharge cycling there is no appreciable loss of charge capacities in the Li Ion battery. Energy densities, cycle characteristics, and memory effects will also be presented. Sponsored by the South Carolina Governor's school for Science and Mathematics under the Summer Program for Research Interns program.

  13. Intensive rainfall recharges tropical groundwaters

    NASA Astrophysics Data System (ADS)

    Jasechko, Scott; Taylor, Richard G.

    2015-12-01

    Dependence upon groundwater to meet rising agricultural and domestic water needs is expected to increase substantially across the tropics where, by 2050, over half of the world’s population is projected to live. Rare, long-term groundwater-level records in the tropics indicate that groundwater recharge occurs disproportionately from heavy rainfalls exceeding a threshold. The ubiquity of this bias in tropical groundwater recharge to intensive precipitation is, however, unknown. By relating available long-term records of stable-isotope ratios of O and H in tropical precipitation (15 sites) to those of local groundwater, we reveal that groundwater recharge in the tropics is near-uniformly (14/15 sites) biased to intensive monthly rainfall, commonly exceeding the ∼70th intensity decile. Our results suggest that the intensification of precipitation brought about by global warming favours groundwater replenishment in the tropics. Nevertheless, the processes that transmit intensive rainfall to groundwater systems and enhance the resilience of tropical groundwater storage in a warming world, remain unclear.

  14. Groundwater recharge and agricultural contamination

    USGS Publications Warehouse

    Böhlke, J.K.

    2002-01-01

    Agriculture has had direct and indirect effects on the rates and compositions of groundwater recharge and aquifer biogeochemistry. Direct effects include dissolution and transport of excess quantities of fertilizers and associated materials and hydrologic alterations related to irrigation and drainage. Some indirect effects include changes in water-rock reactions in soils and aquifers caused by increased concentrations of dissolved oxidants, protons, and major ions. Agrilcultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO3-, N2, Cl, SO42-, H+, P, C, K, Mg, Ca, Sr, Ba, Ra, and As, as well a wide variety of pesticides and other organic compounds. For reactive contaminants like NO3-, a combination of chemical, isotopic, and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. Groundwater records derived from multi-component hydrostratigraphic data can be used to quantify recharge rates and residence times of water and dissolved contaminants, document past variations in recharging contaminant loads, and identify natural contaminant-remediation processes. These data indicate that many of the world's surficial aquifers contain transient records of changing agricultural contamination from the last half of the 20th century. The transient agricultural groundwater signal has important implications for long-term trends and spatial heterogeneity in discharge.

  15. Coupled Model Development between Groundwater Recharge Quantity and Climate Change in Nakdong River Watershed using GIS

    NASA Astrophysics Data System (ADS)

    Lee, M.; Jeongho, L.; Changsub, S.; SeongWoo, J.

    2011-12-01

    : Global climate change is disturbing the water circulation balance by changing rates of precipitation, recharge and discharge, and evapotranspiration. Groundwater, which occupies a considerable portion of the world's water resources, is related to climate change via surface water such as rivers, lakes, and marshes. In this study, the authors selected a relevant climate change scenario, A1B from the Special Report on Emission Scenario (SRES) which is distributed at Korea Meteorological Administration. By using data on temperature, rainfall, soil, and land use, the groundwater recharge rate for the research area was estimated by periodically and embodied as geographic information system (GIS). In order to calculate the groundwater recharge quantity, Visual HELP3 was used as main model, and the physical properties of weather, temperature, and soil layers were used as main input data. General changes to water circulation due to climate change have already been predicted. In order to systematically solve problems of ground circulation system, it may be urgent to recalculate the groundwater recharge quantity and consequent change under future climate change. The space-time calculation of changes of the groundwater recharge quantity in the study area may serve as a foundation to present additional measures to improve domestic groundwater resource management. Results showed that 26.19% of total precipitation was recharged from 1971 to 2000, 27.37% will be recharged from 2001 to 2030, 27.43% will be recharged from 2031 to 2050, and 26.06% will be recharged from 2051 to 2070, 27.88% will be recharged from 2051 to 2100. The groundwater recharge rate in this research showed susceptibility to changes in precipitation. The recharge rate was relatively little affected by the changes in Curve Number (CN), but it was rapidly reduced, as it approached the impermeable layers. Accordingly, the findings herein provide a basis for establishment of national plans on water resources management, use of groundwater in local areas for the purpose of settlement, and estimation of groundwater recharge quantities in areas where the groundwater hydrology is not measured. KEY WORDS: Groundwater recharge; Climate change; Curve Number; Special Report on Emissions Scenarios; Intergovernmental Panel on Climate Change

  16. Evaluation of a rechargeable pacemaker system.

    PubMed

    Stertzer, S H; DePasquale, N P; Cohn, L J; Bruno, M S

    1978-04-01

    A rechargeable-demand nickel-cadmium pulse generator for permanent transvenous cardiac pacing was evaluated in 66 patients. During a cumulative follow-up period of 2,333 patient months (194.4 patient years), failure of the pacing circuit occurred in 3 patients at 21, 25, and 27 months, respectively. Nine patients had difficulty accepting the recharging concept and, in 3 of these patients, it became necessary to replace the rechargeable generator with a conventional energy source. The overall failure rate of approximately 3% per year (including the 3 patients in whom it was necessary to remove the generator because of failure to recharge properly), coupled with the inconvenience of recharging, limits the usefulness of the rechargeable system compared to the newer lithium-powered generator. PMID:83632

  17. Oil fuel delivery optimization for multi product and multi depot: the case of petrol station replenishment problem (PSRP)

    NASA Astrophysics Data System (ADS)

    Surjandari, Isti; Rachman, Amar; Dianawati, Fauzia; Wibowo, R. Pramono

    2011-10-01

    With the Oil and Gas Law No. 22 of 2001, national and foreign private enterprises can invest in all sectors of Oil and Gas in Indonesia. In anticipation of this free competition, Pertamina, as a state-owned enterprises, which previously had monopolized the oil and gas business activities in Indonesia, should be able to improve services as well as the efficiency in order to compete in the free market, especially in terms of cost efficiency of fuel distribution to gas station (SPBU). To optimize the distribution activity, it is necessary to design a scheduling system and its fuel delivery routes daily to every SPBU. The determination of routes and scheduling delivery of fuel to the SPBU can be modeled as a Petrol Station Replenishment Problem (PSRP) with the multi-depot, multi-product, time windows and split deliveries, which in this study will be completed by the Tabu Search algorithm (TS). This study was conducted in the area of Bandung, the capital of West Java province, which is a big city and the neighboring city of Jakarta, the capital city of Indonesia. By using the fuel delivery data for one day, the results showed a decrease of 16.38% of the distance of the route compared to the current conditions, which impacted on the reduction of distribution costs and decrease the number of total trips by 5.22% and 3.83%.

  18. Variability in simulated recharge using different GCMs

    NASA Astrophysics Data System (ADS)

    Allen, D. M.; Cannon, A. J.; Toews, M. W.; Scibek, J.

    2010-10-01

    Variations in the prediction of recharge is addressed by comparing recharge simulated using climate data generated using a state-of-the-art downscaling method, TreeGen, with a range of global climate models (GCMs). The study site is the transnational Abbotsford-Sumas aquifer in coastal British Columbia, Canada and Washington State, USA, and is representative of a wet coastal climate. Sixty-four recharge zones were defined based on combinations of classed soil permeability, vadose zone permeability, and unsaturated zone depth (or depth to water table) mapped in the study area. One-dimensional recharge simulations were conducted for each recharge zone using the HELP hydrologic model, which simulates percolation through a vertical column. The HELP model is driven by mean daily temperature, daily precipitation, and daily solar radiation. For the historical recharge simulations, the climate data series was generated using the LARS-WG stochastic weather generator. Historical recharge was compared to recharge simulated using climate data series derived from the TreeGen downscaling model for three future time periods: 2020s (2010-2039), 2050s (2040-2069), and 2080s (2070-2099) for each of four GCMs (CGCM3.1, ECHAM5, PCM1, and CM2.1). Recharge results are compared on an annual basis for the entire aquifer area. Both increases and decreases relative to historical recharge are simulated depending on time period and model. By the 2080s, the range of model predictions spans -10.5% to +23.2% relative to historical recharge. This variability in recharge predictions suggests that the seasonal performance of the downscaling tool is important and that a range of GCMs should be considered for water management planning.

  19. Rechargeable lithium battery technology - A survey

    NASA Technical Reports Server (NTRS)

    Halpert, Gerald; Surampudi, Subbarao

    1990-01-01

    The technology of the rechargeable lithium battery is discussed with special attention given to the types of rechargeable lithium cells and to their expected performance and advantages. Consideration is also given to the organic-electrolyte and polymeric-electrolyte cells and to molten salt lithium cells, as well as to technical issues, such as the cycle life, charge control, rate capability, cell size, and safety. The role of the rechargeable lithium cell in future NASA applications is discussed.

  20. Development of Carbon Anode for Rechargeable Lithium Cells

    NASA Technical Reports Server (NTRS)

    Huang, C. -K.; Surampudi, S.; Halpert, G.

    1994-01-01

    Conventionally, rechargeable lithium cells employ a pure lithium anode. To overcome problems associated with the pure lithium electrode, it has been proposed to replace the conventional electrode with an alternative material having a greater stability with respect to the cell electrolytes. For this reason, several graphitic and coke based carbonaceous materials were evaluated as candidate anode materials...In this paper, we summarize the results of the studies on Li-ion cell development.

  1. Rechargeable battery operated appliance system

    SciTech Connect

    O'Malley, K.P.; Thomas, R.K.

    1987-03-03

    A rechargeable battery operated appliance system is described comprising: charging stands each having a power cord for plug-in connection to a utility line outlet; rechargeable battery appliances, each having a motor connected through switch means to rechargeable battery means, each charging stand being formed with a recess for receiving and supporting one of the appliances; separable pairs of electrical contacts on the stands and the appliances which are engaged when each appliance is received in each recess to connect the battery means to a charging circuit included in each charging stand; each charging circuit including a step down transformer, the primary of which is connected to the power cord and the secondary of which is connected to one pair of the electrical contacts; a cord storage cavity in each of the charging stands; spaced projections within each cavity on which any excess length of power cord may be wrapped; a plug receptacle mounted in each of the cavities and connected in parallel with the transformer primary to receive power from the power cord. Each charging stand has means for mounting on a vertical wall with the cavity facing the wall and the recess facing away from the wall whereby the appliance is received in the recess and supported by the stand. The charging stands are usable in combination with the power cord of one connected to a power outlet and each other charging stand is connected with its power cord plugged into the plug receptacle of the one charging stand or another charging stand which is powered therefrom.

  2. An innovative artificial recharge system to enhance groundwater storage in basaltic terrain: example from Maharashtra, India

    NASA Astrophysics Data System (ADS)

    Bhusari, Vijay; Katpatal, Y. B.; Kundal, Pradeep

    2016-03-01

    The management of groundwater poses challenges in basaltic terrain as its availability is not uniform due to the absence of primary porosity. Indiscriminate excessive withdrawal from shallow as well as deep aquifers for meeting increased demand can be higher than natural recharge, causing imbalance in demand and supply and leading to a scarcity condition. An innovative artificial recharge system has been conceived and implemented to augment the groundwater sources at the villages of Saoli and Sastabad in Wardha district of Maharashtra, India. The scheme involves resectioning of a stream bed to achieve a reverse gradient, building a subsurface dam to arrest subsurface flow, and installation of recharge shafts to recharge the deeper aquifers. The paper focuses on analysis of hydrogeological parameters like porosity, specific yield and transmissivity, and on temporal groundwater status. Results indicate that after the construction of the artificial recharge system, a rise of 0.8-2.8 m was recorded in the pre- and post-monsoon groundwater levels in 12 dug wells in the study area; an increase in the yield was also noticed which solved the drinking water and irrigation problems. Spatial analysis was performed using a geographic information system to demarcate the area of influence of the recharge system due to increase in yields of the wells. The study demonstrates efficacy, technical viability and applicability of an innovative artificial recharge system constructed in an area of basaltic terrain prone to water scarcity.

  3. Artificial recharge in arid zone- Example from the Arava Valley- Israel

    NASA Astrophysics Data System (ADS)

    Guttman, Joseph

    2010-05-01

    In arid zones direct recharge from rainfall is negligible. The indirect recharge like recharging of flood water is the principal source of water of the alluvial aquifers in arid environment. Flooding of ephemeral streams occur as a consequence of the rain intensity and its pattern, the basin size and the geomorphic settings as slops, vegetation and soil properties. In the Arava Valley there are several reservoirs that act as diversion levees. They were constructed on few ravines for two reasons. (1) to store large volumes of floodwater for direct use in nearby agricultural fields. (2) to enhance the recharge to the local alluvial aquifers. Since flood duration is relatively short compared to the infiltration (percolation) rate, it was assumed that by storing the water in the reservoirs it will increase the recharge volume because of higher water head, longer resistance time and larger surface area available for infiltration. Unfortunately, accumulation of silts and clays in the reservoirs clogged them to direct infiltration. The accumulation of silt and clay in the reservoirs is typically to arid zones where lack of vegetation cover creates a very high erosion rate and transportation of large amounts of sediment at the duration of the water flowing on the stream channel bed. To bypass the problem of reduction in the direct recharge inside the reservoirs because of clogging, and to continue the artificial recharge into the aquifer, two kinds of artificial recharge system are operating in the Arava Valley. In one site we use a system that is similar to the conventional spreading ponds system. The big reservoir is using to store the flood water and as a settling pond. The clean water is diverted to three infiltration ponds. In the rest five reservoirs we construct a drainage pipeline close to the bottom of the levee that allow us to release the clean water (after settling of the fine particles) downstream in a slow rate that is much more efficiency for artificial recharge than in high velocity. Monitoring after the recharge water is very important and in some cases very problematic. In cases where the groundwater is shallow (10-20 m' depth) the response to the recharge is quickly and takes few days (rising in water level and or decreasing in the salinity). But in cases where the water level is very deep (about 60-110 m' in most of the area) the response to the recharge can takes few months. At this condition, it is impossible to distinguish whether the rising in the water level and or decreasing in the salinity is a result of the artificial recharge or it is a result of natural lateral flow in the aquifer itself.

  4. Fuel-Powered Artificial Muscles

    NASA Astrophysics Data System (ADS)

    Ebron, Von Howard; Yang, Zhiwei; Seyer, Daniel J.; Kozlov, Mikhail E.; Oh, Jiyoung; Xie, Hui; Razal, Joselito; Hall, Lee J.; Ferraris, John P.; MacDiarmid, Alan G.; Baughman, Ray H.

    2006-03-01

    Artificial muscles and electric motors found in autonomous robots and prosthetic limbs are typically battery-powered, which severely restricts the duration of their performance and can necessitate long inactivity during battery recharge. To help solve these problems, we demonstrated two types of artificial muscles that convert the chemical energy of high-energy-density fuels to mechanical energy. The first type stores electrical charge and uses changes in stored charge for mechanical actuation. In contrast with electrically powered electrochemical muscles, only half of the actuator cycle is electrochemical. The second type of fuel-powered muscle provides a demonstrated actuator stroke and power density comparable to those of natural skeletal muscle and generated stresses that are over a hundred times higher.

  5. Fuel-powered artificial muscles.

    PubMed

    Ebron, Von Howard; Yang, Zhiwei; Seyer, Daniel J; Kozlov, Mikhail E; Oh, Jiyoung; Xie, Hui; Razal, Joselito; Hall, Lee J; Ferraris, John P; Macdiarmid, Alan G; Baughman, Ray H

    2006-03-17

    Artificial muscles and electric motors found in autonomous robots and prosthetic limbs are typically battery-powered, which severely restricts the duration of their performance and can necessitate long inactivity during battery recharge. To help solve these problems, we demonstrated two types of artificial muscles that convert the chemical energy of high-energy-density fuels to mechanical energy. The first type stores electrical charge and uses changes in stored charge for mechanical actuation. In contrast with electrically powered electrochemical muscles, only half of the actuator cycle is electrochemical. The second type of fuel-powered muscle provides a demonstrated actuator stroke and power density comparable to those of natural skeletal muscle and generated stresses that are over a hundred times higher. PMID:16543453

  6. The used nuclear fuel problem - can reprocessing and consolidated storage be complementary?

    SciTech Connect

    Phillips, C.; Thomas, I.

    2013-07-01

    This paper describes our CISF (Consolidated Interim Storage Facilities) and Reprocessing Facility concepts and show how they can be combined with a geologic repository to provide a comprehensive system for dealing with spent fuels in the USA. The performance of the CISF was logistically analyzed under six operational scenarios. A 3-stage plan has been developed to establish the CISF. Stage 1: the construction at the CISF site of only a rail receipt interface and storage pad large enough for the number of casks that will be received. The construction of the CISF Canister Handling Facility, the Storage Cask Fabrication Facility, the Cask Maintenance Facility and supporting infrastructure are performed during stage 2. The construction and placement into operation of a water-filled pool repackaging facility is completed for Stage 3. By using this staged approach, the capital cost of the CISF is spread over a number of years. It also allows more time for a final decision on the geologic repository to be made. A recycling facility will be built, this facility will used the NUEX recycling process that is based on the aqueous-based PUREX solvent extraction process, using a solvent of tri-N-butyl phosphate in a kerosene diluent. It is capable of processing spent fuels at a rate of 5 MT per day, at burn-ups up to 50 GWD per ton of spent fuels and a minimum of 5 years out-of-reactor cooling.

  7. Transformer Recharging with Alpha Channeling in Tokamaks

    SciTech Connect

    N.J. Fisch

    2009-12-21

    Transformer recharging with lower hybrid waves in tokamaks can give low average auxiliary power if the resistivity is kept high enough during the radio frequency (rf) recharging stage. At the same time, operation in the hot ion mode via alpha channeling increases the effective fusion reactivity. This paper will address the extent to which these two large cost saving steps are compatible. __________________________________________________

  8. INTRODUCTION TO ARTIFICIAL GROUND-WATER RECHARGE

    EPA Science Inventory

    Artificial ground-water recharge has been practiced for scores of years throughout the world. The purpose of artificial recharge is to increase the rate at which water infiltrates the land surface in order to supplement the quantity of ground water in storage. A variety of rechar...

  9. Improved Carbon Anodes For Rechargeable Lithium Cells

    NASA Technical Reports Server (NTRS)

    Huang, Chen-Kuo; Surampudi, Subbarao; Attia, Alan; Halpert, Gerald

    1994-01-01

    Carbon anodes for rechargeable lithium cells improved by choosing binder contents and fabrication conditions to achieve maximum porosity, uniform loading, and maximum reversible lithium capacity. Stacking electrodes under pressure during assembly of cells increases cyclability of lithium. Rechargeable, high-energy-density lithium cells containing improved carbon anodes find use in spacecraft, military, communications, automotive, and other demanding applications.

  10. Recharge at the Hanford Site: Status report

    SciTech Connect

    Gee, G.W.

    1987-11-01

    A variety of field programs designed to evaluate recharge and other water balance components including precipitation, infiltration, evaporation, and water storage changes, have been carried out at the Hanford Site since 1970. Data from these programs have indicated that a wide range of recharge rates can occur depending upon specific site conditions. Present evidence suggests that minimum recharge occurs where soils are fine-textured and surfaces are vegetated with deep-rooted plants. Maximum recharge occurs where coarse soils or gravels exist at the surface and soils are kept bare. Recharge can occur in areas where shallow-rooted plants dominate the surface, particularly where soils are coarse-textured. Recharge estimates have been made for the site using simulation models. A US Geological Survey model that attempts to account for climate variability, soil storage parameters, and plant factors has calculated recharge values ranging from near zero to an average of about 1 cm/yr for the Hanford Site. UNSAT-H, a deterministic model developed for the site, appears to be the best code available for estimating recharge on a site-specific basis. Appendix I contains precipitation data from January 1979 to June 1987. 42 refs., 11 figs., 11 tabs.

  11. Lithium Cells Accept Hundreds Of Recharges

    NASA Technical Reports Server (NTRS)

    Shen, David H.; Surampudi, Subbarao; Deligiannis, Fotios; Halpert, Gerald

    1991-01-01

    New mixed-solvent electrolyte increases number of times room-temperature lithium cell discharged and recharged. Conductivity 70 percent higher. Useful in such other room-temperature rechargeable lithium cells as lithium/niobium triselenide and lithium molybdenum disulfide systems.

  12. Geochemical evidence of natural recharge in Larderello and Castelnuovo areas

    SciTech Connect

    Calore, C.; Celati, R.; D'Amore, F.; Noto, P.

    1982-01-01

    The spatial variations of the isotopic composition of the fluid in Castelnuovo and the southern zone of Larderello were, in the early 1970s, interpreted as the effects of a natural recharge. It was subsequently noted that this distribution might be the result of the condensation process, at least in areas with no tritium. In order to further investigate this problem a study was undertaken of the spatial and temporal variations in the gas/steam ratio and in the isotopic composition. Preliminary interpretation of the results of this study confirms that the evolution of fluid composition in this area is due to a mixing between the fluid originally present in the reservoir and recent meteoric waters. The area affected by natural recharge is, moreover, in continual expansion.

  13. Software problems in the development of the Defense Fuel Automated Management System

    SciTech Connect

    Not Available

    1983-09-06

    A report on a review of the Defense Fuel Automated Management System (DFAMS) is presented. DFAMS is designed as a fully automated integrated system which will handle inventory management, procurement, financial control and accounting for bulk fuel products within the Department of Defense. DFAMS software is being developed with obsolete and vendor-dependent programming techniques. These techniques will cause the delivered system to be unnecessarily costly to maintain and, if incompatible hardware is acquired, lead to high conversion cost. Many commercial software tools are available that run on computers which support ANSI COBOL and can assist in the planning and creation of application systems. It is believed DLA should consider the use of such tools to improve the quality of the DFAMS application software and reduce potential maintenance cost. DFAMS developers do not inspect program code for compliance with DLA, Defense, federal, or ANSI standards. Software tools could greatly reduce the labor of such inspection. The Normalization and ADPER programs appear to be sound ADP management strategies that should achieve DLA's goals of standardizing its software and becoming as machine independent as possible. However, DLA may have difficulty achieving these goals because, at least with DFAMS, it is not enforcing conformance with the Normalization objectives.

  14. Results of the international standard problem No. 31 CORA-13 experiment on severe fuel damage

    SciTech Connect

    Firnhaber, M.; Trambauer, K. ); Hagen, S.; Hofmann, P. )

    1993-01-01

    The definition of an international standard problem (ISP) exercise is a comparative exercise in which predictions with different computer codes for a given physical problem are compared with each other and a carefully controlled experimental study. The main goal of the ISP is to increase confidence in the validity and accuracy of analytical tools that are used in assessing the safety of nuclear installations. Moreover, it enables the code user to gain experience and to improve competence. The related calculation can be performed with or without previous knowledge of the experimental results; therefore two approaches to performing a standard problem exercise can be defined, [open quotes]open[close quotes] or [open quotes]blind.[close quotes] Following a proposal by the Federal Republic of Germany, principal working group (PWG) No. 2 of the Committee on the Safety of Nuclear Installations offered the CORA-13 experiment as ISP No. 31 to its member countries. The ISP, which was sponsored by the German Minister of Research and Technology, was conducted as a [open quotes]blind[close quotes] standard problem; i.e., only the initial and boundary conditions of the experiment were given to the participants for performing their calculations.

  15. Rechargeable lithium-ion cell

    DOEpatents

    Bechtold, Dieter; Bartke, Dietrich; Kramer, Peter; Kretzschmar, Reiner; Vollbert, Jurgen

    1999-01-01

    The invention relates to a rechargeable lithium-ion cell, a method for its manufacture, and its application. The cell is distinguished by the fact that it has a metallic housing (21) which is electrically insulated internally by two half shells (15), which cover electrode plates (8) and main output tabs (7) and are composed of a non-conductive material, where the metallic housing is electrically insulated externally by means of an insulation coating. The cell also has a bursting membrane (4) which, in its normal position, is located above the electrolyte level of the cell (1). In addition, the cell has a twisting protection (6) which extends over the entire surface of the cover (2) and provides centering and assembly functions for the electrode package, which comprises the electrode plates (8).

  16. On the nature of the optimal control problem at leaking underground fuel tank sites

    SciTech Connect

    McDowell, B

    1998-12-01

    In California, leaking underground fuel tank (LUFT) legislation was conceived because of concern that ''time bomb plumes'' would ultimately impact a significant portion of the state's ground and surface water resources. However, it has been found that fuel hydrocarbons (FHC) plumes are stable at relatively short distances from the source in areas of shallow groundwater. In urban areas, these shallow aquifers are not even recommended for use because they are subject to contamination from sewers, storm drains, septic fields and a variety of other sources. After the FHC source has been removed, risk to human health or the environment is insignificant in most cases. For this reason, cleanup to maximum contaminant levels (MCLs) will not significantly reduce the social damages associated with current or near-term human health or ecological risk. Based on these findings, California would be able to save significant resources that had been allocated for LUFT-site cleanup. Non-convexities in the rate of decay function and non-differentiability in the cleanup and social damage functions appear to limit the usefulness of models, such as Caputo and Wilen's (1995), that attempt to characterize the optimal cleanup path using marginal analyses. Furthermore, the effect of active remediation efforts on the natural rate of decay in stable plumes is not taken into account in their model. The imposition of deed restrictions prior to a demonstration of cleanup to MCLs is an additional conservative measure imposed by the California Regional Water Quality Control Boards (RWQCBs) to reduce the uncertainty associated with health risks to future users. These measures impose costs on society in the form of lost rents that have not been considered by regulators. By estimating the differential rents during the time to cleanup, regulators would be able to compare the costs of imposing deed restrictions with the values that society imparts to protection of future users. Both land and water sources are unique in that the value of each is highly dependent upon location. For cost-benefit analysis to be effective, site-specific estimates of property and groundwater values need to be established. Future research may focus on deriving site-specific estimates of restricted and unrestricted land and water usage.

  17. Compliance problems of small utility systems with the Powerplant and Industrial Fuel Use Act of 1978: volume II - appendices

    SciTech Connect

    1981-01-01

    A study of the problems of compliance with the Powerplant and Industrial Fuel Use Act of 1978 experienced by electric utility systems which have a total generating capacity of less than 2000 MW is presented. This volume presents the following appendices: (A) case studies (Farmington, New Mexico; Lamar, Colorado; Dover, Delaware; Wolverine Electric Cooperative, Michigan; Central Telephone and Utilities, Kansas; Sierra Pacific Power Company, Nevada; Vero Beach, Florida; Lubbock, Texas; Western Farmers Cooperative, Oklahoma; and West Texas Utilities Company, Texas); (B) contacts and responses to study; (C) joint action legislation chart; (D) Texas Municipal Power Agency case study; (E) existing generating units jointly owned with small utilities; (F) future generating units jointly owned with small utilities; (G) Federal Register Notice of April 17, 1980, and letter of inquiry to utilities; (H) small utility responses; and (I) Section 744, PIFUA. (WHK)

  18. Advanced rechargeable sodium batteries with novel cathodes

    NASA Technical Reports Server (NTRS)

    Distefano, S.; Ratnakumar, B. V.; Bankston, C. P.

    1989-01-01

    Various high energy density rechargeable batteries are being considered for future space applications. Of these, the sodium-sulfur battery is one of the leading candidates. The primary advantage is the high energy density (760 Wh/kg theoretical). Energy densities in excess of 180 Wh/kg were realized in practical batteries. Other technological advantages include its chemical simplicity, absence of self-discharge, and long cycle life possibility. More recently, other high temperature sodium batteries have come into the spotlight. These systems can be described as follow: Na/Beta Double Prime-Al2O3/NaAlCl4/Metal Dichloride Sodium/metal dichloride systems are colloquially known as the zebra system and are currently being developed for traction and load leveling applications. The sodium-metal dichloride systems appear to offer many of the same advantages of the Na/S system, especially in terms of energy density and chemical simplicity. The metal dichloride systems offer increased safety and good resistance to overcharge and operate over a wide range of temperatures from 150 to 400 C with less corrosion problems.

  19. Groundwater recharge estimation and regionalization: the Great Bend Prairie of central Kansas and its recharge statistics

    USGS Publications Warehouse

    Sophocleous, M.

    1992-01-01

    The results of a 6 year recharge study in the Great Bend Prairie of central Kansas are statistically analyzed to regionalize the limited number of site-specific but year-round measurements. Emphasis is placed on easily measured parameters and field-measured data. The results of the statistical analysis reveal that a typical recharge event in central Kansas lasts 5-7 days, out of which 3 or 4 days are precipitation days with total precipitation of ??? 83 mm. The maximum soil-profile water storage and the maximum groundwater level resulting from the recharge event exhibit the lowest coefficients of variation, whereas the amount of recharge exhibits the highest coefficient of variation. The yearly recharge in the Great Bend Prairie ranged from 0 to 177 mm with a mean of 56 mm. Most of the recharge events occur during the months of April, May, and June, which coincide with the months of highest precipitation in the region. A multiple regression analysis revealed that the most influential variables affecting recharge are, in order of decreasing importance, total annual precipitation average maximum soil-profile water storage during the spring months, average shallowest depth to water table during the same period, and spring rainfall rate. Classification methods, whereby relatively homogeneous hydrologic-unit areas based on the four recharge-affecting variables are identified, were combined with a Geographic Information Systems (ARC/INFO) overlay analysis to derive an area-wide map of differing recharge regions. This recharge zonation is in excellent agreement with the field-site recharge values. The resulting area-weighted average annual recharge for the region is 36 mm. ?? 1992.

  20. MODELING HEAT TRANSFER IN SPENT FUEL TRANSFER CASK NEUTRON SHIELDS – A CHALLENGING PROBLEM IN NATURAL CONVECTION

    SciTech Connect

    Fort, James A.; Cuta, Judith M.; Bajwa, C.; Baglietto, E.

    2010-07-18

    In the United States, commercial spent nuclear fuel is typically moved from spent fuel pools to outdoor dry storage pads within a transfer cask system that provides radiation shielding to protect personnel and the surrounding environment. The transfer casks are cylindrical steel enclosures with integral gamma and neutron radiation shields. Since the transfer cask system must be passively cooled, decay heat removal from spent nuclear fuel canister is limited by the rate of heat transfer through the cask components, and natural convection from the transfer cask surface. The primary mode of heat transfer within the transfer cask system is conduction, but some cask designs incorporate a liquid neutron shield tank surrounding the transfer cask structural shell. In these systems, accurate prediction of natural convection within the neutron shield tank is an important part of assessing the overall thermal performance of the transfer cask system. The large-scale geometry of the neutron shield tank, which is typically an annulus approximately 2 meters in diameter but only 10-15 cm in thickness, and the relatively small scale velocities (typically less than 5 cm/s) represent a wide range of spatial and temporal scales that contribute to making this a challenging problem for computational fluid dynamics (CFD) modeling. Relevant experimental data at these scales are not available in the literature, but some recent modeling studies offer insights into numerical issues and solutions; however, the geometries in these studies, and for the experimental data in the literature at smaller scales, all have large annular gaps that are not prototypic of the transfer cask neutron shield. This paper proposes that there may be reliable CFD approaches to the transfer cask problem, specifically coupled steady-state solvers or unsteady simulations; however, both of these solutions take significant computational effort. Segregated (uncoupled) steady state solvers that were tested did not accurately capture the flow field and heat transfer distribution in this application. Mesh resolution, turbulence modeling, and the tradeoff between steady state and transient solutions are addressed. Because of the critical nature of this application, the need for new experiments at representative scales is clearly demonstrated.

  1. Ways of solving environmental problems while transferring the boilers for burning water-bitumen mixture instead of fuel oil

    NASA Astrophysics Data System (ADS)

    Kotler, V. R.; Sosin, D. V.

    2009-03-01

    Information concerning a new kind (for Russia) of liquid fuel, i.e., water-bitumen mixture (orimulsion), is presented. The application of the new fuel instead of the fuel oil at a boiler of a power unit of 350-MW capacity makes it possible to decrease sufficiently the expenditures for fuel while keeping the main environmental indices.

  2. Proposed artificial recharge studies in northern Qatar

    USGS Publications Warehouse

    Kimrey, J.O.

    1985-01-01

    The aquifer system in northern Qatar comprises a water-table aquifer in the Rus Formation which is separated by an aquitard from a partially confined aquifer in the top of the overlying Umm er Radhuma Formation. These two aquifers are composed of limestone and dolomite of Eocene and Paleocene age and contain a fragile lens of freshwater which is heavily exploited as a source of water for agricultural irrigation. Net withdrawals are greatly in excess of total recharge, and quality of ground water is declining. Use of desalinated seawater for artificial recharge has been proposed for the area. Artificial recharge, on a large scale, could stabilize the decline in ground-water quality while allowing increased withdrawals for irrigation. The proposal appears technically feasible. Recharge should be by injection to the Umm er Radhuma aquifer whose average transmissivity is about 2,000 meters squared per day (as compared to an average of about 200 meters squared per day for the Rus aquifer). Implementation of artificial recharge should be preceded by a hydrogeologic appraisal. These studies should include test drilling, conventional aquifer tests, and recharge-recovery tests at four sites in northern Qatar. (USGS)

  3. Prospects for and problems of using light-water supercritical-pressure coolant in nuclear reactors in order to increase the efficiency of the nuclear fuel cycle

    SciTech Connect

    Alekseev, P. N.; Semchenkov, Yu. M.; Sedov, A. A. Subbotin, S. A.; Chibinyaev, A. V.

    2011-12-15

    Trends in the development of the power sector of the Russian and world power industries both at present time and in the near future are analyzed. Trends in the rise of prices for reserves of fossil and nuclear fuels used for electricity production are compared. An analysis of the competitiveness of electricity production at nuclear power plants as compared to the competitiveness of electricity produced at coal-fired and natural-gas-fired thermal power plants is performed. The efficiency of the open nuclear fuel cycle and various versions of the closed nuclear fuel cycle is discussed. The requirements on light-water reactors under the scenario of dynamic development of the nuclear power industry in Russia are determined. Results of analyzing the efficiency of fuel utilization for various versions of vessel-type light-water reactors with supercritical coolant are given. Advantages and problems of reactors with supercritical-pressure water are listed.

  4. Estimated recharge rates at the Hanford Site

    SciTech Connect

    Fayer, M.J.; Walters, T.B.

    1995-02-01

    The Ground-Water Surveillance Project monitors the distribution of contaminants in ground water at the Hanford Site for the U.S. Department of Energy. A subtask called {open_quotes}Water Budget at Hanford{close_quotes} was initiated in FY 1994. The objective of this subtask was to produce a defensible map of estimated recharge rates across the Hanford Site. Methods that have been used to estimate recharge rates at the Hanford Site include measurements (of drainage, water contents, and tracers) and computer modeling. For the simulations of 12 soil-vegetation combinations, the annual rates varied from 0.05 mm/yr for the Ephrata sandy loam with bunchgrass to 85.2 mm/yr for the same soil without vegetation. Water content data from the Grass Site in the 300 Area indicated that annual rates varied from 3.0 to 143.5 mm/yr during an 8-year period. The annual volume of estimated recharge was calculated to be 8.47 {times} 10{sup 9} L for the potential future Hanford Site (i.e., the portion of the current Site bounded by Highway 240 and the Columbia River). This total volume is similar to earlier estimates of natural recharge and is 2 to 10x higher than estimates of runoff and ground-water flow from higher elevations. Not only is the volume of natural recharge significant in comparison to other ground-water inputs, the distribution of estimated recharge is highly skewed to the disturbed sandy soils (i.e., the 200 Areas, where most contaminants originate). The lack of good estimates of the means and variances of the supporting data (i.e., the soil map, the vegetation/land use map, the model parameters) translates into large uncertainties in the recharge estimates. When combined, the significant quantity of estimated recharge, its high sensitivity to disturbance, and the unquantified uncertainty of the data and model parameters suggest that the defensibility of the recharge estimates should be improved.

  5. Arsenic release during managed aquifer recharge (MAR)

    NASA Astrophysics Data System (ADS)

    Pichler, T.; Lazareva, O.; Druschel, G.

    2013-12-01

    The mobilization and addition of geogenic trace metals to groundwater is typically caused by anthropogenic perturbations of the physicochemical conditions in the aquifer. This can add dangerously high levels of toxins to groundwater, thus compromising its use as a source of drinking water. In several regions world-wide, aquifer storage and recovery (ASR), a form of managed aquifer recharge (MAR), faces the problem of arsenic release due to the injection of oxygenated storage water. To better understand this process we coupled geochemical reactive transport modeling to bench-scale leaching experiments to investigate and verify the mobilization of geogenic arsenic (As) under a range of redox conditions from an arsenic-rich pyrite bearing limestone aquifer in Central Florida. Modeling and experimental observations showed similar results and confirmed the following: (1) native groundwater and aquifer matrix, including pyrite, were in chemical equilibrium, thus preventing the release of As due to pyrite dissolution under ambient conditions; (2) mixing of oxygen-rich surface water with oxygen-depleted native groundwater changed the redox conditions and promoted the dissolution of pyrite, and (3) the behavior of As along a flow path was controlled by a complex series of interconnected reactions. This included the oxidative dissolution of pyrite and simultaneous sorption of As onto neo-formed hydrous ferric oxides (HFO), followed by the reductive dissolution of HFO and secondary release of adsorbed As under reducing conditions. Arsenic contamination of drinking water in these systems is thus controlled by the re-equilibration of the system to more reducing conditions rather than a purely oxidative process.

  6. Transient, spatially varied groundwater recharge modeling

    NASA Astrophysics Data System (ADS)

    Assefa, Kibreab Amare; Woodbury, Allan D.

    2013-08-01

    The objective of this work is to integrate field data and modeling tools in producing temporally and spatially varying groundwater recharge in a pilot watershed in North Okanagan, Canada. The recharge modeling is undertaken by using the Richards equation based finite element code (HYDRUS-1D), ArcGIS™, ROSETTA, in situ observations of soil temperature and soil moisture, and a long-term gridded climate data. The public version of HYDUS-1D and another version with detailed freezing and thawing module are first used to simulate soil temperature, snow pack, and soil moisture over a one year experimental period. Statistical analysis of the results show both versions of HYDRUS-1D reproduce observed variables to the same degree. After evaluating model performance using field data and ROSETTA derived soil hydraulic parameters, the HYDRUS-1D code is coupled with ArcGIS™ to produce spatially and temporally varying recharge maps throughout the Deep Creek watershed. Temporal and spatial analysis of 25 years daily recharge results at various representative points across the study watershed reveal significant temporal and spatial variations; average recharge estimated at 77.8 ± 50.8 mm/year. Previous studies in the Okanagan Basin used Hydrologic Evaluation of Landfill Performance without any attempt of model performance evaluation, notwithstanding its inherent limitations. Thus, climate change impact results from this previous study and similar others, such as Jyrkama and Sykes (2007), need to be interpreted with caution.

  7. Towards a calcium-based rechargeable battery.

    PubMed

    Ponrouch, A; Frontera, C; Bardé, F; Palacín, M R

    2016-02-01

    The development of a rechargeable battery technology using light electropositive metal anodes would result in a breakthrough in energy density. For multivalent charge carriers (M(n+)), the number of ions that must react to achieve a certain electrochemical capacity is diminished by two (n = 2) or three (n = 3) when compared with Li(+) (ref. ). Whereas proof of concept has been achieved for magnesium, the electrodeposition of calcium has so far been thought to be impossible and research has been restricted to non-rechargeable systems. Here we demonstrate the feasibility of calcium plating at moderate temperatures using conventional organic electrolytes, such as those used for the Li-ion technology. The reversibility of the process on cycling has been ascertained and thus the results presented here constitute the first step towards the development of a new rechargeable battery technology using calcium anodes. PMID:26501412

  8. Towards a calcium-based rechargeable battery

    NASA Astrophysics Data System (ADS)

    Ponrouch, A.; Frontera, C.; Bardé, F.; Palacín, M. R.

    2016-02-01

    The development of a rechargeable battery technology using light electropositive metal anodes would result in a breakthrough in energy density. For multivalent charge carriers (Mn+), the number of ions that must react to achieve a certain electrochemical capacity is diminished by two (n = 2) or three (n = 3) when compared with Li+ (ref. ). Whereas proof of concept has been achieved for magnesium, the electrodeposition of calcium has so far been thought to be impossible and research has been restricted to non-rechargeable systems. Here we demonstrate the feasibility of calcium plating at moderate temperatures using conventional organic electrolytes, such as those used for the Li-ion technology. The reversibility of the process on cycling has been ascertained and thus the results presented here constitute the first step towards the development of a new rechargeable battery technology using calcium anodes.

  9. Experimental studies in natural groundwater-recharge dynamics: The analysis of observed recharge events

    USGS Publications Warehouse

    Sophocleous, M.; Perry, C.A.

    1985-01-01

    The amounts and time distribution of groundwater recharge from precipitation over an approximately 19-month period were investigated at two instrumented sites in south-central Kansas. Precipitation and evapotranspiration sequences, soil-moisture profiles and storage changes, water fluxes in the unsaturated zone and hydraulic gradients in the saturated zone at various depths, soil temperatures, water-table hydrographs, and water-level changes in nearby wells clearly depict the recharge process. Antecedent moisture conditions and the thickness and nature of the unsaturated zone were found to be the major factors affecting recharge. Although the two instrumented sites are located in sand-dune environments in areas characterized by shallow water table and subhumid continental climate, a significant difference was observed in the estimated effective recharge. The estimates ranged from less than 2.5 to approximately 154 mm at the two sites from February to June 1983. The main reasons for this large difference in recharge estimates were the greater thickness of the unsaturated zone and the lower moisture content in that zone resulting from lower precipitation and higher potential evapotranspiration for one of the sites. Effective recharge took place only during late winter and spring. No summer or fall recharge was observed at either site during the observation period of this study. ?? 1985.

  10. A critical assessment of simple recharge models: application to the UK Chalk

    NASA Astrophysics Data System (ADS)

    Ireson, A. M.; Butler, A. P.

    2012-10-01

    A framework for the rigorous quantification of the timing and magnitude of groundwater recharge is proposed. This involves developing a physically based model for the flow processes in the unsaturated and saturated zones that is consistent with the conceptualisation of the system, and with field observations. Subsequently, the essential behaviour of this model is emulated using a simpler model that can be applied within operational groundwater models. We take a UK Chalk aquifer as a case study. Flow processes are simulated convincingly using a dual permeability, equivalent continuum, Richards' equation model, applied to a 2-D hillslope transect along which four monitoring wells recorded water levels in the unconfined aquifer. A simple conventional recharge model that has been widely used was calibrated to reproduce the water table response simulated by the physically based model. The performance in reproducing the water table was surprisingly good, given the known discrepancies between the actual processes and the model representation. However, comparisons of recharge fluxes simulated by each model highlighted problems with the recharge processes in the simple model. Specifically, artificial bypass flow events during the summer were compensating for recharge that should have come from slow, continual drainage of the unsaturated zone. Such a model may still be useful for assessment of groundwater resources on a monthly basis, under non-extreme climatic conditions. However, under extreme wet or dry conditions, or under a changed climate the predictive capacity of such models is likely to be inadequate.

  11. Improved Separators For Rechargeable Lithium Cells

    NASA Technical Reports Server (NTRS)

    Shen, David; Surampudi, Subbarao; Huang, Chen-Kuo; Halpert, Gerald

    1994-01-01

    Improved pairs of separators proposed for use in rechargeable lithium cells operating at ambient temperature. Block growth of lithium dendrites and help prevent short circuits. Each cell contains one separator made of microporous polypropylene placed next to anode, and one separator made of microporous polytetrafluoroethylene (PTFE) next to cathode. Separators increase cycle lives of secondary lithium cells. Cells to which concept applicable those of Li/TiS(2), Li/NbSe(3), Li/CoO(2), Li/MoS(2), Li/VO(x), and Li/MnO(2) chemical systems. Advantageous in spacecraft, military, communications, automotive, and other applications in which high energy density and rechargeability needed.

  12. Solid polymer electrolytes for rechargeable batteries. Final report

    SciTech Connect

    Narang, S.C.; Ventura, S.C.

    1992-02-01

    SRI International has synthesized and tested new, dimensionally stable polymer electrolytes for high energy density rechargeable lithium batteries. We have prepared semi-interpenetrating networks of sulfur-substituted polyethyleneoxide with tetmethylorthosilicate (TEOS). The in situ hydrolysis of TEOS produces a mechanically stable three-dimensional network that entangles the polymer electrolytes and makes the film dimensionally flexible and stable. With this approach, the best dimensionally stable polymer electrolyte of this type produced so far, has a room temperature lithium ion conductivity of 7.5 {times} 10{sup {minus}4} S cm{sup {minus}1}. Another type of solid polymer electrolytes, polydiacetylene-based single-ion conductors with high room temperature proton conductivity were also developed. The best conductivity of these polymers is two orders of magnitude higher than that of Nafion under comparable experimental conditions. With further appropriate chemical modification, the new polymers could be used in fuel cells.

  13. REFLEAK: NIST Leak/Recharge Simulation Program for Refrigerant Mixtures

    National Institute of Standards and Technology Data Gateway

    SRD 73 NIST REFLEAK: NIST Leak/Recharge Simulation Program for Refrigerant Mixtures (PC database for purchase)   REFLEAK estimates composition changes of zeotropic mixtures in leak and recharge processes.

  14. The Response of Groundwater to Artificial Recharge Schemes

    NASA Astrophysics Data System (ADS)

    Latinopoulos, P.

    1981-12-01

    Analytic solutions are presented for the groundwater flow in an unconfined aquifer under seasonal artificial recharge schemes of variable duration. The results can be used for a preliminary assessment of the response of groundwater to artificial recharge. Variations in storage and outflow from the aquifer, apart from the siting of recharge, are also highly dependent on both the aquifer characteristics and the duration of recharge.

  15. Behavior of TOC in a Deep Confined Aquifer During Groundwater Artificial Recharge Process

    NASA Astrophysics Data System (ADS)

    Zhang, W.; He, H.; Shi, X.

    2013-12-01

    In recent years, environmental geological problems such as land subsidence, land collapse, land cracking and salt-water intrusion have become important factors limiting economic development in some cities due to severe overexploitation of groundwater. So, a number of cities have carried out artificial recharge projects, which have played a significant role in controlling these problems. However, with the increasing trend of organic pollution appeared in the surface water, organic contaminated problems should not be neglected during this process. Although the organic components were always following in a lower concentration level, whether it would make groundwater face the organic pollution crisis was unknown for its' higher toxicity and durability. Based on a typical artificial recharge test carried out in a deep confined aquifer in this study area (located in Eastern China, there are 10 monitoring wells and 1 recharge well) that decided to control the field land subsidence, Total Organic Carbon (TOC) was selected as the target components to reveal the organic elements' changing trend during groundwater artificial recharge process. The results (Fig. 1) showed that the concentration of TOC in each monitoring well was appeared in an increasing trend due to the mix influence of the recharge water (TOC was 1.88mg/L) and the origin groundwater (TOC was 0.58mg/L). But the maximum concentrations of TOC in J4, J5, J6 monitoring well (the distance from recharge well was 10m, 17m, 31m respectively) were lower than the recharge water 0.28, 0.49, 0.74 mg/L respectively, with non-linear growth. It indicated that except adsorption, microbial degradation might also occur in the aquifer during artificial recharge. With the groundwater environment from relatively anaerobic environment turn to aerobic environment, DO was able to characterize the relative strength of the TOC biodegradation. The average value of DO in recharge water was 4.33 mg/L, and the maximum value of DO in J4, J5, J6 monitoring well was about 2.54, 2.43, 2.22 mg/L, respectively. All of that showed the farther distance from the recharge well to monitoring wells, the smaller change in the value of DO. It suggested that biodegradation function was in a relative weakening trend away from the recharge position. Based on the complete control of geological, hydrogeological and hydrogeochemical conditions of the test site, GMS (groundwater modelling system) was used to simulate and forecast the TOC changing trend in the deep confined aquifer. The numerical results indicated the radius of influence (over 1.6mg/L) was 170m, 220m and 270m respectively after continuous recharge during 1 year, 2 year and 5 year.

  16. Anodes for Rechargeable Lithium-Sulfur Batteries

    SciTech Connect

    Cao, Ruiguo; Xu, Wu; Lu, Dongping; Xiao, Jie; Zhang, Jiguang

    2015-04-10

    In this work, we will review the recent developments on the protection of Li metal anode in Li-S batteries. Various strategies used to minimize the corrosion of Li anode and reducing its impedance increase will be analyzed. Other potential anodes used in sulfur based rechargeable batteries will also be discussed.

  17. Design considerations for rechargeable lithium batteries

    NASA Technical Reports Server (NTRS)

    Shen, D. H.; Huang, C.-K.; Davies, E.; Perrone, D.; Surampudi, S.; Halpert, Gerald

    1993-01-01

    Viewgraphs of a discussion of design considerations for rechargable lithium batteries. The objective is to determine the influence of cell design parameters on the performance of Li-TiS2 cells. Topics covered include cell baseline design and testing, cell design and testing, cell design parameters studies, and cell cycling performance.

  18. Recharging Our Sense of Idealism: Concluding Thoughts

    ERIC Educational Resources Information Center

    D'Andrea, Michael; Dollarhide, Colette T.

    2011-01-01

    In this article, the authors aim to recharge one's sense of idealism. They argue that idealism is the Vitamin C that sustains one's commitment to implementing humanistic principles and social justice practices in the work of counselors and educators. The idealism that characterizes counselors and educators who are humanistic and social justice…

  19. Rechargeable antimicrobial surface modification of polyethylene.

    PubMed

    Goddard, J M; Hotchkiss, J H

    2008-10-01

    Polyethylene films were surface modified, to incorporate amine and amide functionalities, and subsequently were evaluated for their ability to recharge the antimicrobial N-halamine structures after contact with sodium hypochlorite, a common food-approved sanitizer. Surfaces were tested for chlorine retention and release, as well as antimicrobial activity against microorganisms relevant to food quality and food safety, including Escherichia coli K-12, Pseudomonas fluorescens, Bacillus cereus, and Listeria monocytogenes. N-Halamine functionalized polyethylene exhibited chlorine rechargeability, maintaining 5 to 7 nmol/cm2 N-halamine structures for six successive charges. The N-halamine functionalized films achieved a 4-log reduction for all organisms tested and maintained a greater than 3-log reduction for four successive uses, suggesting that the modified polyethylene films are capable of providing rechargeable antimicrobial activity. The modified films exhibited antimicrobial activity in aqueous suspensions (P < 0.05) and reduced microbial growth in diluted broth (P < 0.05), suggesting the potential for biocidal action even in the presence of organic matter. Such a rechargeable antimicrobial surface could supplement existing cleaning and sanitation programs in food processing environments to reduce the adhesion, growth, and subsequent cross-contamination of food pathogens, as well as food spoilage organisms. PMID:18939750

  20. Recharging Our Sense of Idealism: Concluding Thoughts

    ERIC Educational Resources Information Center

    D'Andrea, Michael; Dollarhide, Colette T.

    2011-01-01

    In this article, the authors aim to recharge one's sense of idealism. They argue that idealism is the Vitamin C that sustains one's commitment to implementing humanistic principles and social justice practices in the work of counselors and educators. The idealism that characterizes counselors and educators who are humanistic and social justice

  1. Alloys of clathrate allotropes for rechargeable batteries

    DOEpatents

    Chan, Candace K; Miller, Michael A; Chan, Kwai S

    2014-12-09

    The present disclosure is directed at an electrode for a battery wherein the electrode comprises clathrate alloys of silicon, germanium or tin. In method form, the present disclosure is directed at methods of forming clathrate alloys of silicon, germanium or tin which methods lead to the formation of empty cage structures suitable for use as electrodes in rechargeable type batteries.

  2. Rechargeable solid polymer electrolyte battery cell

    DOEpatents

    Skotheim, Terji

    1985-01-01

    A rechargeable battery cell comprising first and second electrodes sandwiching a solid polymer electrolyte comprising a layer of a polymer blend of a highly conductive polymer and a solid polymer electrolyte adjacent said polymer blend and a layer of dry solid polymer electrolyte adjacent said layer of polymer blend and said second electrode.

  3. Geochemical quantification of semiarid mountain recharge.

    PubMed

    Wahi, Arun K; Hogan, James F; Ekwurzel, Brenda; Baillie, Matthew N; Eastoe, Christopher J

    2008-01-01

    Analysis of a typical semiarid mountain system recharge (MSR) setting demonstrates that geochemical tracers help resolve the location, rate, and seasonality of recharge as well as ground water flowpaths and residence times. MSR is defined as the recharge at the mountain front that dominates many semiarid basins plus the often-overlooked recharge through the mountain block that may be a significant ground water resource; thus, geochemical measurements that integrate signals from all flowpaths are advantageous. Ground water fluxes determined from carbon-14 ((14)C) age gradients imply MSR rates between 2 x 10(6) and 9 x 10(6) m(3)/year in the Upper San Pedro Basin, Arizona, USA. This estimated range is within an order of magnitude of, but lower than, prior independent estimates. Stable isotopic signatures indicate that MSR has a 65% +/- 25% contribution from winter precipitation and a 35% +/- 25% contribution from summer precipitation. Chloride and stable isotope results confirm that transpiration is the dominant component of evapotranspiration (ET) in the basin with typical loss of more than 90% of precipitation-less runoff to ET. Such geochemical constraints can be used to further refine hydrogeologic models in similar high-elevation relief basins and can provide practical first estimates of MSR rates for basins lacking extensive prior hydrogeologic measurements. PMID:18194314

  4. Anode for rechargeable ambient temperature lithium cells

    NASA Technical Reports Server (NTRS)

    Huang, Chen-Kuo (Inventor); Surampudi, Subbarao (Inventor); Attia, Alan I. (Inventor); Halpert, Gerald (Inventor)

    1994-01-01

    An ambient room temperature, high density, rechargeable lithium battery includes a Li(x)Mg2Si negative anode which intercalates lithium to form a single crystalline phase when x is up to 1.0 and an amorphous phase when x is from 1 to 2.0. The electrode has good reversibility and mechanical strength after cycling.

  5. Regional Analysis of Ground-Water Recharge

    USGS Publications Warehouse

    Flint, Lorraine E.; Flint, Alan L.

    2007-01-01

    A modeling analysis of runoff and ground-water recharge for the arid and semiarid southwestern United States was performed to investigate the interactions of climate and other controlling factors and to place the eight study-site investigations into a regional context. A distributed-parameter water-balance model (the Basin Characterization Model, or BCM) was used in the analysis. Data requirements of the BCM included digital representations of topography, soils, geology, and vegetation, together with monthly time-series of precipitation and air-temperature data. Time-series of potential evapotranspiration were generated by using a submodel for solar radiation, taking into account topographic shading, cloudiness, and vegetation density. Snowpack accumulation and melting were modeled using precipitation and air-temperature data. Amounts of water available for runoff and ground-water recharge were calculated on the basis of water-budget considerations by using measured- and generated-meteorologic time series together with estimates of soil-water storage and saturated hydraulic conductivity of subsoil geologic units. Calculations were made on a computational grid with a horizontal resolution of about 270 meters for the entire 1,033,840 square-kilometer study area. The modeling analysis was composed of 194 basins, including the eight basins containing ground-water recharge-site investigations. For each grid cell, the BCM computed monthly values of potential evapotranspiration, soil-water storage, in-place ground-water recharge, and runoff (potential stream flow). A fixed percentage of runoff was assumed to become recharge beneath channels operating at a finer resolution than the computational grid of the BCM. Monthly precipitation and temperature data from 1941 to 2004 were used to explore climatic variability in runoff and ground-water recharge. The selected approach provided a framework for classifying study-site basins with respect to climate and dominant recharge processes. The average climate for all 194 basins ranged from hyperarid to humid, with arid and semiarid basins predominating (fig. 6, chapter A, this volume). Four of the 194 basins had an aridity index of dry subhumid; two of the basins were humid. Of the eight recharge-study sites, six were in semiarid basins, and two were in arid basins. Average-annual potential evapotranspiration showed a regional gradient from less than 1 m/yr in the northeastern part of the study area to more than 2 m/yr in the southwestern part of the study area. Average-annual precipitation was lowest in the two arid-site basins and highest in the two study-site basins in southern Arizona. The relative amount of runoff to in-place recharge varied throughout the study area, reflecting differences primarily in soil water-holding capacity, saturated hydraulic conductivity of subsoil materials, and snowpack dynamics. Climatic forcing expressed in El Ni?o and Pacific Decadal Oscillation indices strongly influenced the generation of precipitation throughout the study area. Positive values of both indices correlated with the highest amounts of runoff and ground-water recharge.

  6. Research on rechargeable oxygen electrodes.

    NASA Technical Reports Server (NTRS)

    Giner, J.; Holleck, G.; Malachesky, P. A.

    1970-01-01

    A research program is described which consisted of studying the effects of electrode cycling in very pure KOH solutions, with and without controlled additions of impurities, on oxide formation, oxygen evolution kinetics, oxygen reduction kinetics (including hydrogen peroxide formation), and changes in electrode structure. Bright platinum, platinized platinum, and Teflon-bonded platinum black electrodes were studied. Three main problem areas are identified: the buildup of a refractory anodic layer on prolonged cycling, which leads to a degradation of performance; the dissolution and subsequent deposition of dendritic platinum in the separator, leading to short-circuit ing and loss of electrocatalyst; and the disruptive effect of bubbling during gas evolution on charge. Each of these problem areas is analyzed, and remedial solutions are proposed.

  7. Analysis of regenerative fuel cells

    NASA Technical Reports Server (NTRS)

    Gross, S.

    1982-01-01

    The concept of a rechargeable fuel cell (RFC) system is considered. A newer type of rechargeable battery, the nickel hydrogen (Ni-H2) battery, is also evaluated. A review was made of past studies which showed large variations in weight, cost, and efficiency. Hydrogen-bromine and hydrogen-chlorine regenerable fuel cells were studied, and were found to have a potential for higher energy storage efficiency then the hydrogen-oxygen system. A reduction of up to 15 percent in solar array size may be possible as a result. These systems are not yet developed, but further study of them is recommended.

  8. Assessing the impact of future climate change on groundwater recharge in Galicia-Costa, Spain

    NASA Astrophysics Data System (ADS)

    Raposo, Juan Ramón; Dafonte, Jorge; Molinero, Jorge

    2013-03-01

    Climate change can impact the hydrological processes of a watershed and may result in problems with future water supply for large sections of the population. Results from the FP5 PRUDENCE project suggest significant changes in temperature and precipitation over Europe. In this study, the Soil and Water Assessment Tool (SWAT) model was used to assess the potential impacts of climate change on groundwater recharge in the hydrological district of Galicia-Costa, Spain. Climate projections from two general circulation models and eight different regional climate models were used for the assessment and two climate-change scenarios were evaluated. Calibration and validation of the model were performed using a daily time-step in four representative catchments in the district. The effects on modeled mean annual groundwater recharge are small, partly due to the greater stomatal efficiency of plants in response to increased CO2 concentration. However, climate change strongly influences the temporal variability of modeled groundwater recharge. Recharge may concentrate in the winter season and dramatically decrease in the summer-autumn season. As a result, the dry-season duration may be increased on average by almost 30 % for the A2 emission scenario, exacerbating the current problems in water supply.

  9. Water balance-based estimation of groundwater recharge in the Lake Chad Basin

    NASA Astrophysics Data System (ADS)

    Babamaaji, R. A.; Lee, J.

    2012-12-01

    Lake Chad Basin (LCB) has experienced drastic changes of land cover and poor water management practices during the last 50 years. The successive droughts in the 1970s and 1980s resulted in the shortage of surface water and groundwater resources. This problem of drought and shortage of water has a devastating implication on the natural resources of the Basin with great consequence on food security, poverty reduction and quality of life of the inhabitants in the LCB. Therefore, understanding the change of land use and its characteristics must be a first step to find how such changes disturb the water cycle especially the groundwater in the LCB. The abundance of groundwater is affected by the climate change through the interaction with surface water, such as lakes and rivers, and vertical recharge through an infiltration process. Quantifying the impact of climate change on the groundwater resource requires not only reliable forecasting of changes in the major climatic variables, but also accurate estimation of groundwater recharge. Spatial variations in the land use/land cover, soil texture, topographic slope, and meteorological conditions should be accounted for in the recharge estimation. In this study, we employed a spatially distributed water balance model WetSpass to simulate a long-term average change of groundwater recharge in the LCB of Africa. WetSpass is a water balance-based model to estimate seasonal average spatial distribution of surface runoff, evapotranspiration, and groundwater recharge. The model is especially suitable for studying the effect of land use/land cover change on the water regime in the LCB. The present study describes the concept of the model and its application to the development of recharge map of the LCB.

  10. Fossil Fuels.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fossil fuels. Some topics covered are historic facts, development of fuels, history of oil production, current and future trends of the oil industry, refining fossil fuels, and environmental problems. Material in each unit may…

  11. Fossil Fuels.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fossil fuels. Some topics covered are historic facts, development of fuels, history of oil production, current and future trends of the oil industry, refining fossil fuels, and environmental problems. Material in each unit may

  12. The Study of Cross-layer Optimization for Wireless Rechargeable Sensor Networks Implemented in Coal Mines.

    PubMed

    Ding, Xu; Shi, Lei; Han, Jianghong; Lu, Jingting

    2016-01-01

    Wireless sensor networks deployed in coal mines could help companies provide workers working in coal mines with more qualified working conditions. With the underground information collected by sensor nodes at hand, the underground working conditions could be evaluated more precisely. However, sensor nodes may tend to malfunction due to their limited energy supply. In this paper, we study the cross-layer optimization problem for wireless rechargeable sensor networks implemented in coal mines, of which the energy could be replenished through the newly-brewed wireless energy transfer technique. The main results of this article are two-fold: firstly, we obtain the optimal relay nodes' placement according to the minimum overall energy consumption criterion through the Lagrange dual problem and KKT conditions; secondly, the optimal strategies for recharging locomotives and wireless sensor networks are acquired by solving a cross-layer optimization problem. The cyclic nature of these strategies is also manifested through simulations in this paper. PMID:26828500

  13. The Study of Cross-layer Optimization for Wireless Rechargeable Sensor Networks Implemented in Coal Mines

    PubMed Central

    Ding, Xu; Shi, Lei; Han, Jianghong; Lu, Jingting

    2016-01-01

    Wireless sensor networks deployed in coal mines could help companies provide workers working in coal mines with more qualified working conditions. With the underground information collected by sensor nodes at hand, the underground working conditions could be evaluated more precisely. However, sensor nodes may tend to malfunction due to their limited energy supply. In this paper, we study the cross-layer optimization problem for wireless rechargeable sensor networks implemented in coal mines, of which the energy could be replenished through the newly-brewed wireless energy transfer technique. The main results of this article are two-fold: firstly, we obtain the optimal relay nodes’ placement according to the minimum overall energy consumption criterion through the Lagrange dual problem and KKT conditions; secondly, the optimal strategies for recharging locomotives and wireless sensor networks are acquired by solving a cross-layer optimization problem. The cyclic nature of these strategies is also manifested through simulations in this paper. PMID:26828500

  14. Alternative fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J. S.; Butze, H. F.; Friedman, R.; Antoine, A. C.; Reynolds, T. W.

    1977-01-01

    Potential problems related to the use of alternative aviation turbine fuels are discussed and both ongoing and required research into these fuels is described. This discussion is limited to aviation turbine fuels composed of liquid hydrocarbons. The advantages and disadvantages of the various solutions to the problems are summarized. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source. The second solution is to minimize energy consumption at the refinery and keep fuel costs down by relaxing specifications.

  15. Nanocomposite polymer electrolyte for rechargeable magnesium batteries

    SciTech Connect

    Shao, Yuyan; Rajput, Nav Nidhi; Hu, Jian Z.; Hu, Mary Y.; Liu, Tianbiao L.; Wei, Zhehao; Gu, Meng; Deng, Xuchu; Xu, Suochang; Han, Kee Sung; Wang, Jiulin; Nie, Zimin; Li, Guosheng; Zavadil, K.; Xiao, Jie; Wang, Chong M.; Henderson, Wesley A.; Zhang, Jiguang; Wang, Yong; Mueller, Karl T.; Persson, Kristin A.; Liu, Jun

    2015-03-01

    Nanocomposite polymer electrolytes present new opportunities for rechargeable magnesium batteries. However, few polymer electrolytes have demonstrated reversible Mg deposition/dissolution and those that have still contain volatile liquids such as tetrahydrofuran (THF). In this work, we report a nanocomposite polymer electrolyte based on poly(ethylene oxide) (PEO), Mg(BH4)2 and MgO nanoparticles for rechargeable Mg batteries. Cells with this electrolyte have a high coulombic efficiency of 98% for Mg plating/stripping and a high cycling stability. Through combined experiment-modeling investigations, a correlation between improved solvation of the salt and solvent chain length, chelation and oxygen denticity is established. Following the same trend, the nanocomposite polymer electrolyte is inferred to enhance the dissociation of the salt Mg(BH4)2 and thus improve the electrochemical performance. The insights and design metrics thus obtained may be used in nanocomposite electrolytes for other multivalent systems.

  16. Rechargeable lithium batteries with aqueous electrolytes.

    PubMed

    Li, W; Dahn, J R; Wainwright, D S

    1994-05-20

    Rechargeable lithium-ion batteries that use an aqueous electrolyte have been developed. Cells with LiMn(2)O(4) and VO(2)(B) as electrodes and 5 M LiNO(3) in water as the electrolyte provide a fundamentally safe and cost-effective technology that can compete with nickelcadmium and lead-acid batteries on the basis of stored energy per unit of weight. PMID:17744893

  17. Ampere-Hour Meter For Rechargeable Battery

    NASA Technical Reports Server (NTRS)

    Tripp, John S.; Schott, Timothy D.; Tcheng, Ping

    1993-01-01

    Low-power analog/digital electronic circuit meters discharge of storage battery in ampere-hours. By metering discharge, one obtains indication of state of charge of battery and avoids unnecessary recharging, maintaining capacity of battery and prolonging life. Because of its small size and low power consumption, useful in such applications as portable video cameras, communication equipment on boats, portable audio equipment, and portable medical equipment.

  18. Recharge monitoring in an interplaya setting

    SciTech Connect

    Scanlon, B.R.; Reedy, R.C.; Liang, J.

    1999-03-01

    The objective of this investigation is to monitor infiltration in response to precipitation events in an interplaya setting. The authors evaluated data gathered from the interplaya recharge monitoring installation at the Pantex Plant from March through December 1998. They monitored thermocouple psychrometer (TCP) instruments to measure water potential and time-domain reflectometry (TDR) probes to measure water content and bulk soil conductivity. Heat-dissipation sensor (HDS) instruments were monitored to supplement the TCP data.

  19. The rechargeable aluminum-ion battery

    SciTech Connect

    Navaneedhakrishnan, Jayaprakash; Das, Shyamal K; Archer, Lynden A.

    2011-01-01

    We report a novel aluminium-ion rechargeable battery comprised of an electrolyte containing AlCl₃ in the ionic liquid, 1-ethyl-3-methylimidazolium chloride, and a V₂O₅ nano-wire cathode against an aluminium metal anode. The battery delivered a discharge capacity of 305 mAh g⁻¹ in the first cycle and 273 mAh g⁻¹ after 20 cycles, with very stable electrochemical behaviour.

  20. Dendrites Inhibition in Rechargeable Lithium Metal Batteries

    NASA Astrophysics Data System (ADS)

    Aryanfar, Asghar

    The specific high energy and power capacities of rechargeable lithium metal (Li0) batteries are ideally suited to portable devices and are valuable as storage units for intermittent renewable energy sources. Lithium, the lightest and most electropositive metal, would be the optimal anode material for rechargeable batteries if it were not for the fact that such devices fail unexpectedly by short-circuiting via the dendrites that grow across electrodes upon recharging. This phenomenon poses a major safety issue because it triggers a series of adverse events that start with overheating, potentially followed by the thermal decomposition and ultimately the ignition of the organic solvents used in such devices. In this thesis, we developed experimental platform for monitoring and quantifying the dendrite populations grown in a Li battery prototype upon charging under various conditions. We explored the effects of pulse charging in the kHz range and temperature on dendrite growth, and also on loss capacity into detached "dead" lithium particles. Simultaneously, we developed a computational framework for understanding the dynamics of dendrite propagation. The coarse-grained Monte Carlo model assisted us in the interpretation of pulsing experiments, whereas MD calculations provided insights into the mechanism of dendrites thermal relaxation. We also developed a computational framework for measuring the dead lithium crystals from the experimental images.

  1. Ground water recharge from Lake Chad

    SciTech Connect

    Isiorho, S.; Matisoff, G.; McCall, P.L.

    1985-01-01

    Lake Chad is a shallow, closed basin lake located in Sub-Sharan Africa. It has the largest drainage basin of any lake in the world, and is also very old, being formed by tectonic processes during the Cretaceous. These features should combine to form a saline lake, but the open waters of Lake Chad are reasonably fresh, having a total dissolved solids concentration of about 320 mg/1. This apparent discrepancy can be explained by noting that recharge of the unconfined aquifer to the SW in Nigeria by ground water infiltration through the lakebed can remove significant quantities of water and dissolved solutes from the lake. The authors have measured and calculated ground water infiltration and velocities by several techniques. Direct, volumetric measurements of ground water recharge seepage give velocities on the order of .28-8.8 x 10/sup -3/ m/day. Tracer monitoring in a borehole dilution test yielded ground water velocities of 3.6 m/day to the SW (away from the lake). Hydraulic conductivities approx. .004-.6 m/day were determined by falling head measurements. Finally, using static water levels, the potentiometric surface within approx. 80 km of the southwest portion of Lake Chad yields water table gradients of 1.0-1.7 x 10/sup -4/ away from the lake. These results confirm that surface water and solute inflow to Lake Chad is removed by recharge to the unconfined aquifer in Nigeria.

  2. A regression model to estimate regional ground water recharge

    USGS Publications Warehouse

    Lorenz, D.L.; Delin, G.N.

    2007-01-01

    A regional regression model was developed to estimate the spatial distribution of ground water recharge in subhumid regions. The regional regression recharge (RRR) model was based on a regression of basin-wide estimates of recharge from surface water drainage basins, precipitation, growing degree days (GDD), and average basin specific yield (SY). Decadal average recharge, precipitation, and GDD were used in the RRR model. The RRR estimates were derived from analysis of stream base flow using a computer program that was based on the Rorabaugh method. As expected, there was a strong correlation between recharge and precipitation. The model was applied to statewide data in Minnesota. Where precipitation was least in the western and northwestern parts of the state (50 to 65 cm/year), recharge computed by the RRR model also was lowest (0 to 5 cm/year). A strong correlation also exists between recharge and SY. SY was least in areas where glacial lake clay occurs, primarily in the northwest part of the state; recharge estimates in these areas were in the 0- to 5-cm/year range. In sand-plain areas where SY is greatest, recharge estimates were in the 15- to 29-cm/year range on the basis of the RRR model. Recharge estimates that were based on the RRR model compared favorably with estimates made on the basis of other methods. The RRR model can be applied in other subhumid regions where region wide data sets of precipitation, streamflow, GDD, and soils data are available.

  3. Comet whole-core solution to a stylized 3-dimensional pressurized water reactor benchmark problem with UO{sub 2}and MOX fuel

    SciTech Connect

    Zhang, D.; Rahnema, F.

    2012-07-01

    A stylized pressurized water reactor (PWR) benchmark problem with UO{sub 2} and MOX fuel was used to test the accuracy and efficiency of the coarse mesh radiation transport (COMET) code. The benchmark problem contains 125 fuel assemblies and 44,000 fuel pins. The COMET code was used to compute the core eigenvalue and assembly and pin power distributions for three core configurations. In these calculations, a set of tensor products of orthogonal polynomials were used to expand the neutron angular phase space distribution on the interfaces between coarse meshes. The COMET calculations were compared with the Monte Carlo code MCNP reference solutions using a recently published an 8-group material cross section library. The comparison showed both the core eigenvalues and assembly and pin power distributions predicated by COMET agree very well with the MCNP reference solution if the orders of the angular flux expansion in the two spatial variables and the polar and azimuth angles on the mesh boundaries are 4, 4, 2 and 2. The mean and maximum differences in the pin fission density distribution ranged from 0.28%-0.44% and 3.0%-5.5%, all within 3-sigma uncertainty of the MCNP solution. These comparisons indicate that COMET can achieve accuracy comparable to Monte Carlo. It was also found that COMET's computational speed is 450 times faster than MCNP. (authors)

  4. Estimating long-term regional groundwater recharge for the evaluation of potential solution alternatives to waterlogging and salinisation

    NASA Astrophysics Data System (ADS)

    Singh, Ajay

    2011-09-01

    SummaryAccurate estimation of the groundwater recharge is essential for efficient and sustainable groundwater management in arid and semi-arid regions, as water resources are critical to economic development in these areas. Various techniques are available to quantify recharge. The hydrological budget model proposed herein is unique, simple, and easy to apply. It uses data on groundwater level, groundwater extraction, and distributed specific yield information for estimating groundwater recharge. The Model is employed to estimate the seasonal long-term (35 years, e.g., from 1974 to 2009) groundwater recharge of an irrigated semi-arid area located in Haryana State of India, where groundwater levels are rising, continuously. The results are analysed to provide an overview of the process dynamics that led to imbalance of the system. Groundwater recharge analysis during the study period reveals that percolation from irrigated fields is the main recharge component with 49% contribution to the total recharge. An annual groundwater table rise of 0.14 m has been estimated for the study area. Various potential solution alternatives are evaluated to mitigate the problems of waterlogging and salinisation, considering the socio-economic issues which have wider policy significance on sustainability. Several suitable water management strategies such as reduction in rice area, increase in pumping volume and using the groundwater conjunctively with higher quality canal water, and lining of canal networks are suggested to bring the watertable down to a safe limit and to prevent further rising of the watertable. Among the potential solution alternatives studied, the one which considers 10% reduction in rice area along with 2% increase in pumping volume and 20% canal lining, yields best result for mitigating the waterlogging problems.

  5. The Li-ion rechargeable battery: a perspective.

    PubMed

    Goodenough, John B; Park, Kyu-Sung

    2013-01-30

    Each cell of a battery stores electrical energy as chemical energy in two electrodes, a reductant (anode) and an oxidant (cathode), separated by an electrolyte that transfers the ionic component of the chemical reaction inside the cell and forces the electronic component outside the battery. The output on discharge is an external electronic current I at a voltage V for a time Δt. The chemical reaction of a rechargeable battery must be reversible on the application of a charging I and V. Critical parameters of a rechargeable battery are safety, density of energy that can be stored at a specific power input and retrieved at a specific power output, cycle and shelf life, storage efficiency, and cost of fabrication. Conventional ambient-temperature rechargeable batteries have solid electrodes and a liquid electrolyte. The positive electrode (cathode) consists of a host framework into which the mobile (working) cation is inserted reversibly over a finite solid-solution range. The solid-solution range, which is reduced at higher current by the rate of transfer of the working ion across electrode/electrolyte interfaces and within a host, limits the amount of charge per electrode formula unit that can be transferred over the time Δt = Δt(I). Moreover, the difference between energies of the LUMO and the HOMO of the electrolyte, i.e., electrolyte window, determines the maximum voltage for a long shelf and cycle life. The maximum stable voltage with an aqueous electrolyte is 1.5 V; the Li-ion rechargeable battery uses an organic electrolyte with a larger window, which increase the density of stored energy for a given Δt. Anode or cathode electrochemical potentials outside the electrolyte window can increase V, but they require formation of a passivating surface layer that must be permeable to Li(+) and capable of adapting rapidly to the changing electrode surface area as the electrode changes volume during cycling. A passivating surface layer adds to the impedance of the Li(+) transfer across the electrode/electrolyte interface and lowers the cycle life of a battery cell. Moreover, formation of a passivation layer on the anode robs Li from the cathode irreversibly on an initial charge, further lowering the reversible Δt. These problems plus the cost of quality control of manufacturing plague development of Li-ion rechargeable batteries that can compete with the internal combustion engine for powering electric cars and that can provide the needed low-cost storage of electrical energy generated by renewable wind and/or solar energy. Chemists are contributing to incremental improvements of the conventional strategy by investigating and controlling electrode passivation layers, improving the rate of Li(+) transfer across electrode/electrolyte interfaces, identifying electrolytes with larger windows while retaining a Li(+) conductivity σ(Li) > 10(-3) S cm(-1), synthesizing electrode morphologies that reduce the size of the active particles while pinning them on current collectors of large surface area accessible by the electrolyte, lowering the cost of cell fabrication, designing displacement-reaction anodes of higher capacity that allow a safe, fast charge, and designing alternative cathode hosts. However, new strategies are needed for batteries that go beyond powering hand-held devices, such as using electrode hosts with two-electron redox centers; replacing the cathode hosts by materials that undergo displacement reactions (e.g. sulfur) by liquid cathodes that may contain flow-through redox molecules, or by catalysts for air cathodes; and developing a Li(+) solid electrolyte separator membrane that allows an organic and aqueous liquid electrolyte on the anode and cathode sides, respectively. Opportunities exist for the chemist to bring together oxide and polymer or graphene chemistry in imaginative morphologies. PMID:23294028

  6. High energy density rechargeable magnesium battery using earth-abundant and non-toxic elements.

    PubMed

    Orikasa, Yuki; Masese, Titus; Koyama, Yukinori; Mori, Takuya; Hattori, Masashi; Yamamoto, Kentaro; Okado, Tetsuya; Huang, Zhen-Dong; Minato, Taketoshi; Tassel, Cédric; Kim, Jungeun; Kobayashi, Yoji; Abe, Takeshi; Kageyama, Hiroshi; Uchimoto, Yoshiharu

    2014-01-01

    Rechargeable magnesium batteries are poised to be viable candidates for large-scale energy storage devices in smart grid communities and electric vehicles. However, the energy density of previously proposed rechargeable magnesium batteries is low, limited mainly by the cathode materials. Here, we present new design approaches for the cathode in order to realize a high-energy-density rechargeable magnesium battery system. Ion-exchanged MgFeSiO4 demonstrates a high reversible capacity exceeding 300 Ah · g(-1) at a voltage of approximately 2.4 V vs. Mg. Further, the electronic and crystal structure of ion-exchanged MgFeSiO4 changes during the charging and discharging processes, which demonstrates the (de)insertion of magnesium in the host structure. The combination of ion-exchanged MgFeSiO4 with a magnesium bis(trifluoromethylsulfonyl)imide-triglyme electrolyte system proposed in this work provides a low-cost and practical rechargeable magnesium battery with high energy density, free from corrosion and safety problems. PMID:25011939

  7. High energy density rechargeable magnesium battery using earth-abundant and non-toxic elements

    NASA Astrophysics Data System (ADS)

    Orikasa, Yuki; Masese, Titus; Koyama, Yukinori; Mori, Takuya; Hattori, Masashi; Yamamoto, Kentaro; Okado, Tetsuya; Huang, Zhen-Dong; Minato, Taketoshi; Tassel, Cédric; Kim, Jungeun; Kobayashi, Yoji; Abe, Takeshi; Kageyama, Hiroshi; Uchimoto, Yoshiharu

    2014-07-01

    Rechargeable magnesium batteries are poised to be viable candidates for large-scale energy storage devices in smart grid communities and electric vehicles. However, the energy density of previously proposed rechargeable magnesium batteries is low, limited mainly by the cathode materials. Here, we present new design approaches for the cathode in order to realize a high-energy-density rechargeable magnesium battery system. Ion-exchanged MgFeSiO4 demonstrates a high reversible capacity exceeding 300 mAh.g-1 at a voltage of approximately 2.4 V vs. Mg. Further, the electronic and crystal structure of ion-exchanged MgFeSiO4 changes during the charging and discharging processes, which demonstrates the (de)insertion of magnesium in the host structure. The combination of ion-exchanged MgFeSiO4 with a magnesium bis(trifluoromethylsulfonyl)imide-triglyme electrolyte system proposed in this work provides a low-cost and practical rechargeable magnesium battery with high energy density, free from corrosion and safety problems.

  8. High energy density rechargeable magnesium battery using earth-abundant and non-toxic elements

    PubMed Central

    Orikasa, Yuki; Masese, Titus; Koyama, Yukinori; Mori, Takuya; Hattori, Masashi; Yamamoto, Kentaro; Okado, Tetsuya; Huang, Zhen-Dong; Minato, Taketoshi; Tassel, Cédric; Kim, Jungeun; Kobayashi, Yoji; Abe, Takeshi; Kageyama, Hiroshi; Uchimoto, Yoshiharu

    2014-01-01

    Rechargeable magnesium batteries are poised to be viable candidates for large-scale energy storage devices in smart grid communities and electric vehicles. However, the energy density of previously proposed rechargeable magnesium batteries is low, limited mainly by the cathode materials. Here, we present new design approaches for the cathode in order to realize a high-energy-density rechargeable magnesium battery system. Ion-exchanged MgFeSiO4 demonstrates a high reversible capacity exceeding 300 mAh·g−1 at a voltage of approximately 2.4 V vs. Mg. Further, the electronic and crystal structure of ion-exchanged MgFeSiO4 changes during the charging and discharging processes, which demonstrates the (de)insertion of magnesium in the host structure. The combination of ion-exchanged MgFeSiO4 with a magnesium bis(trifluoromethylsulfonyl)imide–triglyme electrolyte system proposed in this work provides a low-cost and practical rechargeable magnesium battery with high energy density, free from corrosion and safety problems. PMID:25011939

  9. Shale recharge and production behavior of geopressured reservoirs

    SciTech Connect

    Garg, S.K.

    1980-04-01

    The reservoir simulator MUSHRM was used to study the conditions under which significant shale recharge may be expected. The calculations presented herein show that shale recharge is a strong function of the vertical shale permeability but is not greatly influenced by the shale compressibility. Significant shale recharge will occur only if the vertical shale permeability is at least of the order of 0.01 ..mu..d.

  10. Generator and rechargeable battery system for pedal powered vehicles

    SciTech Connect

    Ryan, D.

    1985-11-26

    A generator and rechargeable battery system for use with pedal powered vehicles, such as bicycles, and where either the generator or battery can intermittently power a load such as a lighting system of the vehicle in one mode of operation, and in which the generator can recharge the battery in another mode of operation. A simple selection switch which is manually operable by the operator of the vehicle enables selection between powering of the load or recharging of the battery.

  11. Making Li-air batteries rechargeable: material challenges

    SciTech Connect

    Shao, Yuyan; Ding, Fei; Xiao, Jie; Zhang, Jian; Xu, Wu; Park, Seh Kyu; Zhang, Jiguang; Wang, Yong; Liu, Jun

    2013-02-25

    A Li-air battery could potentially provide three to five times higher energy density/specific energy than conventional batteries, thus enable the driving range of an electric vehicle comparable to a gasoline vehicle. However, making Li-air batteries rechargeable presents significant challenges, mostly related with materials. Herein, we discuss the key factors that influence the rechargeability of Li-air batteries with a focus on nonaqueous system. The status and materials challenges for nonaqueous rechargeable Li-air batteries are reviewed. These include electrolytes, cathode (electocatalysts), lithium metal anodes, and oxygen-selective membranes (oxygen supply from air). The perspective of rechargeable Li-air batteries is provided.

  12. A review of groundwater recharge under irrigated agriculture in Australia

    NASA Astrophysics Data System (ADS)

    Riasat, Ali; Mallants, Dirk; Walker, Glen; Silberstein, Richard

    2014-05-01

    Quantification of recharge under irrigated agriculture is one of the most important but difficult tasks. It is the least understood component in groundwater studies because of its large variability in space and time and the difficulty of direct measurement. Better management of groundwater resources is only possible if we can accurately determine all fluxes going into and out of a groundwater system. One of the major challenges facing irrigated agriculture in Australia, and the world, is to reduce uncertainty in estimating or measuring the recharge flux. Reducing uncertainty in groundwater recharge under irrigated agriculture is a pre-requisite for effective, efficient and sustainable groundwater resource management especially in dry areas where groundwater usage is often the key to economic development. An accurate quantification of groundwater recharge under irrigated systems is also crucial because of its potential impacts on soil profile salinity, groundwater levels and groundwater quality. This paper aims to identify the main recharge control parameters thorough a review of past field and modelling recharge studies in Australia. We find that the main recharge control parameters under irrigated agriculture are soil type, irrigation management, watertable depth, land cover or plant water uptake, soil surface conditions, and soil, irrigation water and groundwater chemistry. The most commonly used recharge estimation approaches include chloride mass balance, water budget equation, lysimeters, Darcy's law and numerical models. Main sources and magnitude of uncertainty in recharge estimates associated with these approaches are discussed.

  13. Geophysical Methods for Investigating Ground-Water Recharge

    USGS Publications Warehouse

    Ferre, Ty P.A.; Binley, Andrew M.; Blasch, Kyle W.; Callegary, James B.; Crawford, Steven M.; Fink, James B.; Flint, Alan L.; Flint, Lorraine E.; Hoffmann, John P.; Izbicki, John A.; Levitt, Marc T.; Pool, Donald R.; Scanlon, Bridget R.

    2007-01-01

    While numerical modeling has revolutionized our understanding of basin-scale hydrologic processes, such models rely almost exclusively on traditional measurements?rainfall, streamflow, and water-table elevations?for calibration and testing. Model calibration provides initial estimates of ground-water recharge. Calibrated models are important yet crude tools for addressing questions about the spatial and temporal distribution of recharge. An inverse approach to recharge estimation is taken of necessity, due to inherent difficulties in making direct measurements of flow across the water table. Difficulties arise because recharging fluxes are typically small, even in humid regions, and because the location of the water table changes with time. Deep water tables in arid and semiarid regions make recharge monitoring especially difficult. Nevertheless, recharge monitoring must advance in order to improve assessments of ground-water recharge. Improved characterization of basin-scale recharge is critical for informed water-resources management. Difficulties in directly measuring recharge have prompted many efforts to develop indirect methods. The mass-balance approach of estimating recharge as the residual of generally much larger terms has persisted despite the use of increasing complex and finely gridded large-scale hydrologic models. Geophysical data pertaining to recharge rates, timing, and patterns have the potential to substantially improve modeling efforts by providing information on boundary conditions, by constraining model inputs, by testing simplifying assumptions, and by identifying the spatial and temporal resolutions needed to predict recharge to a specified tolerance in space and in time. Moreover, under certain conditions, geophysical measurements can yield direct estimates of recharge rates or changes in water storage, largely eliminating the need for indirect measures of recharge. This appendix presents an overview of physically based, geophysical methods that are currently available or under development for recharge monitoring. The material is written primarily for hydrogeologists. Uses of geophysical methods for improving recharge monitoring are explored through brief discussions and case studies. The intent is to indicate how geophysical methods can be used effectively in studying recharge processes and quantifying recharge. As such, the material constructs a framework for matching the strengths of individual geophysical methods with the manners in which they can be applied for hydrologic analyses. The appendix is organized in three sections. First, the key hydrologic parameters necessary to determine the rate, timing, and patterns of recharge are identified. Second, the basic operating principals of the relevant geophysical methods are discussed. Methods are grouped by the physical property that they measure directly. Each measured property is related to one or more of the key hydrologic properties for recharge monitoring. Third, the emerging conceptual framework for applying geophysics to recharge monitoring is presented. Examples of the application of selected geophysical methods to recharge monitoring are presented in nine case studies. These studies illustrate hydrogeophysical applications under a wide range of conditions and measurement scales, which vary from tenths of a meter to hundreds of meters. The case studies include practice-proven as well as emerging applications of geophysical methods to recharge monitoring.

  14. Fuel dehazers

    SciTech Connect

    Lyons, W.R.

    1986-03-01

    Hazy fuels can be caused by the emulsification of water into the fuel during refining, blending, or transportation operations. Detergent additive packages used in gasoline tend to emulsify water into the fuel. Fuels containing water haze can cause corrosion and contamination, and support microbiological growth. This results in problems. As the result of these problems, refiners, marketers, and product pipeline companies customarily have haze specifications. The haze specification may be a specific maximum water content or simply ''bright and clear'' at a specified temperature.

  15. Polyphase alloys as rechargeable electrodes in advanced battery systems

    NASA Technical Reports Server (NTRS)

    Huggins, Robert A.

    1987-01-01

    The rechargeability of electrochemical cells is often limited by negative electrode problems. These may include loss of capacity, increased impedance, macroscopic shape change, dendrite growth, or a tendency for filamentary or whisker growth. In principle, these problems can be reduced or eliminated by the use of alloys that undergo either displacement or insertion reactions at reactant species activities less than unity, rather than pure elements. The fundamental reasons for some of these problems with elemental electrodes, as well as the basic principles involved in the different behavior of alloys, are briefly discussed. More information is now available concerning the thermodynamic and kinetic properties of a number of alloys of potential interest for use as electrodes in elevated temperature lithium battery systems. Recent results have extended these results down to ambient temperatures, indicating that some such materials may be of interest for use with new low temperature molten salt electrolytes, or with organic solvent electrolytes. The all solid mixed conductor matrix concept is also reviewed.

  16. Glossary of testing terminology for rechargeable batteries

    SciTech Connect

    Butler, P.C.

    1988-10-01

    The Battery Test Working Task Force was formed in 1983 for the purpose of coordinating the evaluation of development rechargeable batteries by DOE-funded labs. The Task Force developed this glossary of testing terminology to improve the accuracy of communication and to permit meaningful comparisons of test results. It consists of a section of technical terms and a separate section of programmatic phrases and acronyms. The glossary emphasizes terms related to electric vehicle batteries due to the significant development and testing activities in this area. 8 refs.

  17. Thin-film Rechargeable Lithium Batteries

    DOE R&D Accomplishments Database

    Dudney, N. J.; Bates, J. B.; Lubben, D.

    1995-06-01

    Thin film rechargeable lithium batteries using ceramic electrolyte and cathode materials have been fabricated by physical deposition techniques. The lithium phosphorous oxynitride electrolyte has exceptional electrochemical stability and a good lithium conductivity. The lithium insertion reaction of several different intercalation materials, amorphous V{sub 2}O{sub 5}, amorphous LiMn{sub 2}O{sub 4}, and crystalline LiMn{sub 2}O{sub 4} films, have been investigated using the completed cathode/electrolyte/lithium thin film battery.

  18. Experimental survey of rechargeable alkaline zinc electrodes

    NASA Astrophysics Data System (ADS)

    Binder, L.; Odar, W.

    1984-09-01

    Rechargeable alkaline zinc-air cells and zinc-manganese dioxide cells need zinc electrodes working for at least 100 cycles under anode limiting conditions. The discharge of the manganese dioxide cathode especially must be limited to a definite fraction (1/3) of its available capacity to obtain a good cycle life. This study proposes a new test cell for investigations on pasted alkaline zinc powder electrodes. When, following experimentation, the value of the construction was established, a series of different electrode mixtures was cycled. It was found that 100 full discharges could be obtained with a zinc utilization of about 30 percent in the final cycles.

  19. Rechargeable lithium/polymer cathode batteries

    NASA Astrophysics Data System (ADS)

    Osaka, Tetsuya; Nakajima, Toshiki; Shiota, Koh; Owens, Boone B.

    1989-06-01

    Polypyrrole (PPy) and polyaniline (PAn) were investigated for cathode materials of rechargeable lithium batteries. PPy films prepared with PF6(-) anion and/or platinum substrate precoated with nitrile butadiene rubber (NBR) were excellent cathode materials because of rough and/or highly oriented film structure. PAn films were successfully prepared from non-aqueous propylene carbonate solution containing aniline, CF3COOH and lithium perchlorate. Its acidity strongly affects the anion doping-undoping behavior. The PAn cathode prepared in high acidic solution (e.g., 4:1 ratio of acid:aniline) gives the excellent battery performance.

  20. Organic Cathode Materials for Rechargeable Batteries

    SciTech Connect

    Cao, Ruiguo; Qian, Jiangfeng; Zhang, Jiguang; Xu, Wu

    2015-06-28

    This chapter will primarily focus on the advances made in recent years and specify the development of organic electrode materials for their applications in rechargeable lithium batteries, sodium batteries and redox flow batteries. Four various organic cathode materials, including conjugated carbonyl compounds, conducting polymers, organosulfides and free radical polymers, are introduced in terms of their electrochemical performances in these three battery systems. Fundamental issues related to the synthesis-structure-activity correlations, involved work principles in energy storage systems, and capacity fading mechanisms are also discussed.

  1. Evolution of strategies for modern rechargeable batteries.

    PubMed

    Goodenough, John B

    2013-05-21

    This Account provides perspective on the evolution of the rechargeable battery and summarizes innovations in the development of these devices. Initially, I describe the components of a conventional rechargeable battery along with the engineering parameters that define the figures of merit for a single cell. In 1967, researchers discovered fast Na(+) conduction at 300 K in Na β,β''-alumina. Since then battery technology has evolved from a strongly acidic or alkaline aqueous electrolyte with protons as the working ion to an organic liquid-carbonate electrolyte with Li(+) as the working ion in a Li-ion battery. The invention of the sodium-sulfur and Zebra batteries stimulated consideration of framework structures as crystalline hosts for mobile guest alkali ions, and the jump in oil prices in the early 1970s prompted researchers to consider alternative room-temperature batteries with aprotic liquid electrolytes. With the existence of Li primary cells and ongoing research on the chemistry of reversible Li intercalation into layered chalcogenides, industry invested in the production of a Li/TiS2 rechargeable cell. However, on repeated recharge, dendrites grew across the electrolyte from the anode to the cathode, leading to dangerous short-circuits in the cell in the presence of the flammable organic liquid electrolyte. Because lowering the voltage of the anode would prevent cells with layered-chalcogenide cathodes from competing with cells that had an aqueous electrolyte, researchers quickly abandoned this effort. However, once it was realized that an oxide cathode could offer a larger voltage versus lithium, researchers considered the extraction of Li from the layered LiMO2 oxides with M = Co or Ni. These oxide cathodes were fabricated in a discharged state, and battery manufacturers could not conceive of assembling a cell with a discharged cathode. Meanwhile, exploration of Li intercalation into graphite showed that reversible Li insertion into carbon occurred without dendrite formation. The SONY corporation used the LiCoO2/carbon battery to power their initial cellular telephone and launched the wireless revolution. As researchers developed 3D transition-metal hosts, manufacturers introduced spinel and olivine hosts in the Lix[Mn2]O4 and LiFe(PO4) cathodes. However, current Li-ion batteries fall short of the desired specifications for electric-powered automobiles and the storage of electrical energy generated by wind and solar power. These demands are stimulating new strategies for electrochemical cells that can safely and affordably meet those challenges. PMID:22746097

  2. Using noble gases to investigate mountain-front recharge

    NASA Astrophysics Data System (ADS)

    Manning, Andrew H.; Solomon, D. Kip

    2003-05-01

    Mountain-front recharge is a major component of recharge to inter-mountain basin-fill aquifers. The two components of mountain-front recharge are (1) subsurface inflow from the mountain block (subsurface inflow), and (2) infiltration from perennial and ephemeral streams near the mountain front (stream seepage). The magnitude of subsurface inflow is of central importance in source protection planning for basin-fill aquifers and in some water rights disputes, yet existing estimates carry large uncertainties. Stable isotope ratios can indicate the magnitude of mountain-front recharge relative to other components, but are generally incapable of distinguishing subsurface inflow from stream seepage. Noble gases provide an effective tool for determining the relative significance of subsurface inflow, specifically. Dissolved noble gas concentrations allow for the determination of recharge temperature, which is correlated with recharge elevation. The nature of this correlation cannot be assumed, however, and must be derived for the study area. The method is applied to the Salt Lake Valley Principal Aquifer in northern Utah to demonstrate its utility. Samples from 16 springs and mine tunnels in the adjacent Wasatch Mountains indicate that recharge temperature decreases with elevation at about the same rate as the mean annual air temperature, but is on average about 2 °C cooler. Samples from 27 valley production wells yield recharge elevations ranging from the valley elevation (about 1500 m) to mid-mountain elevation (about 2500 m). Only six of the wells have recharge elevations less than 1800 m. Recharge elevations consistently greater than 2000 m in the southeastern part of the basin indicate that subsurface inflow constitutes most of the total recharge in this area.

  3. 77 FR 8325 - Sixth Meeting: RTCA Special Committee 225, Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-14

    ... TRANSPORTATION Federal Aviation Administration Sixth Meeting: RTCA Special Committee 225, Rechargeable Lithium.... Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 225, Rechargeable Lithium... public of the sixth meeting of RTCA Special Committee 225, Rechargeable Lithium Batteries and...

  4. 77 FR 20688 - Seventh Meeting: RTCA Special Committee 225, Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-05

    ... Federal Aviation Administration Seventh Meeting: RTCA Special Committee 225, Rechargeable Lithium.... Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 225, Rechargeable Lithium... public of the seventh meeting of RTCA Special Committee 225, Rechargeable Lithium Batteries and...

  5. Rechargeable Thin-film Lithium Batteries

    DOE R&D Accomplishments Database

    Bates, J. B.; Gruzalski, G. R.; Dudney, N. J.; Luck, C. F.; Yu, Xiaohua

    1993-08-01

    Rechargeable thin film batteries consisting of lithium metal anodes, an amorphous inorganic electrolyte, and cathodes of lithium intercalation compounds have recently been developed. The batteries, which are typically less than 6 {mu}m thick, can be fabricated to any specified size, large or small, onto a variety of substrates including ceramics, semiconductors, and plastics. The cells that have been investigated include Li TiS{sub 2}, Li V{sub 2}O{sub 5}, and Li Li{sub x}Mn{sub 2}O{sub 4}, with open circuit voltages at full charge of about 2.5, 3.6, and 4.2, respectively. The development of these batteries would not have been possible without the discovery of a new thin film lithium electrolyte, lithium phosphorus oxynitride, that is stable in contact with metallic lithium at these potentials. Deposited by rf magnetron sputtering of Li{sub 3}PO{sub 4} in N{sub 2}, this material has a typical composition of Li{sub 2.9}PO{sub 3.3}N{sub 0.46} and a conductivity at 25{degrees}C of 2 {mu}S/cm. The maximum practical current density obtained from the thin film cells is limited to about 100 {mu}A/cm{sup 2} due to a low diffusivity of Li{sup +} ions in the cathodes. In this work, the authors present a short review of their work on rechargeable thin film lithium batteries.

  6. Lithium Metal Anodes for Rechargeable Batteries

    SciTech Connect

    Xu, Wu; Wang, Jiulin; Ding, Fei; Chen, Xilin; Nasybulin, Eduard N.; Zhang, Yaohui; Zhang, Jiguang

    2013-10-29

    Rechargeable lithium metal batteries have much higher energy density than those of lithium ion batteries using graphite anode. Unfortunately, uncontrollable dendritic lithium growth inherent in these batteries (upon repeated charge/discharge cycling) and limited Coulombic efficiency during lithium deposition/striping has prevented their practical application over the past 40 years. With the emerging of post Li-ion batteries, safe and efficient operation of lithium metal anode has become an enabling technology which may determine the fate of several promising candidates for the next generation of energy storage systems, including rechargeable Li-air battery, Li-S battery, and Li metal battery which utilize lithium intercalation compounds as cathode. In this work, various factors which affect the morphology and Coulombic efficiency of lithium anode will be analyzed. Technologies used to characterize the morphology of lithium deposition and the results obtained by modeling of lithium dendrite growth will also be reviewed. At last, recent development in this filed and urgent need in this field will also be discussed.

  7. Impacts on groundwater recharge areas of megacity pumping: analysis of potential contamination of Kolkata, India, water supply

    USGS Publications Warehouse

    Sahu, Paulami; Michael, Holly A.; Voss, Clifford I.; Sikdar, Pradip K.

    2013-01-01

    Water supply to the world's megacities is a problem of quantity and quality that will be a priority in the coming decades. Heavy pumping of groundwater beneath these urban centres, particularly in regions with low natural topographic gradients, such as deltas and floodplains, can fundamentally alter the hydrological system. These changes affect recharge area locations, which may shift closer to the city centre than before development, thereby increasing the potential for contamination. Hydrogeological simulation analysis allows evaluation of the impact on past, present and future pumping for the region of Kolkata, India, on recharge area locations in an aquifer that supplies water to over 13 million people. Relocated recharge areas are compared with known surface contamination sources, with a focus on sustainable management of this urban groundwater resource. The study highlights the impacts of pumping on water sources for long-term development of stressed city aquifers and for future water supply in deltaic and floodplain regions of the world.

  8. Artificial groundwater recharge as integral part of a water resources system in a humid environment

    NASA Astrophysics Data System (ADS)

    Kupfersberger, Hans; Stadler, Hermann

    2010-05-01

    In Graz, Austria, artificial groundwater recharge has been operated as an integral part of the drinking water supply system for more than thirty years. About 180 l/s of high quality water from pristine creeks (i.e. no pre-treatment necessary) are infiltrated via sand and lawn basins and infiltration trenches into two phreatic aquifers to sustain the extraction of approximately 400 l/s. The remaining third of drinking water for roughly 300.000 people is provided by a remote supply line from the East alpine karst region Hochschwab. By this threefold model the water supply system is less vulnerable to external conditions. In the early 1980's the infiltration devices were also designed as a hydraulic barrier against riverbank infiltration from the river Mur, which at that time showed seriously impaired water quality due to upstream paper mills. This resulted into high iron and manganese groundwater concentrations which lead to clogging of the pumping wells. These problems have been eliminated in the meantime due to the onsite purification of paper mill effluents and the construction of many waste water treatment plants. The recharge system has recently been thoroughly examined to optimize the operation of groundwater recharge and to provide a basis for further extension. The investigations included (i) field experiments and laboratory analyses to improve the trade off between infiltration rate and elimination capacities of the sand filter basins' top layer, (ii) numerical groundwater modelling to compute the recovery rate of the recharged water, the composition of the origin of the pumped water, emergency scenarios due to the failure of system parts, the transient capture zones of the withdrawal wells and the coordination of recharge and withdrawal and (iii) development of an online monitoring setup combined with a decision support system to guarantee reliable functioning of the entire structure. Additionally, the depreciation, maintenance and operation costs of the managed aquifer recharge system have been evaluated. Among numerous results it could be shown that replacing the lawn by sand basins and operating them constantly during winter holds the largest potential to increase the infiltration volume. However, this is only an option for new to build structures since the current basin positions would lead to large direct losses of recharged groundwater into the river Mur. Adjusting the timing of infiltration and withdrawal based on subsurface travel time yields an increase of the pumped amount of about 11% given about the same extension the wells' capture zones. The overall costs of artificial groundwater recharge amount to 0,15 €/m³ excluding pumping and distribution costs compared to a water price of about 1,5 €/m³ charged to consumers. Currently, the implications of building a hydro power plant adjacent to the recharge site are evaluated emphasizing the need for innovative solutions given only limited land resources. On the basis of the projected impacts of climate change on the availability of surface water and groundwater in the South-Eastern alpine regions, the aquifers can act as a buffer system to help overcome the timely shift between supply and demand. Thus, also in predominantly humid regions artificial groundwater recharge represents a viable and sustainable solution to safeguard the supply of drinking water in the long term.

  9. Availability of streamflow for recharge of the basal aquifer in the Pearl Harbor area, Hawaii

    USGS Publications Warehouse

    Hirashima, George Tokusuke

    1971-01-01

    The Pearl Harbor area is underlain by an extensive basal aquifer that contains large supplies of fresh water. Because of the presence of a cap rock composed of sedimentary material that is less permeable than the basaltic lava of the basal aquifer, seaward movement of ground water is retarded. The cap rock causes the basal water to stand at a high level; thus, the lens of fresh water that floats on sea water is thick. Discharge from the basal ground-water body, which includes pumpage from wells and shafts, averaged 250 million gallons per day during 1931-65. Because the water level in the basal aquifer did not decline progressively, recharge to the ground-water body must have been approximately equal to discharge. Although pumping for agricultural use has decreased since 1931, net ground-water discharge has increased because of a large increase in pumping for urban use. Substitution of ground water for surface water in the irrigation of sugarcane has also contributed to a net increase in ground-water discharge. The development of Mililani Town will further increase discharge. The increase in ground-water discharge may cause an increase in chloride content of the water pumped from wells near the shore of Pearl Harbor unless the increased discharge is balanced by increased recharge to the local aquifer. The aquifer is recharged by direct infiltration and deep percolation of rain, principally in the high forested area, by infiltration and percolation of irrigation water applied in excess of plant requirements, by seepage of water through streambeds, and possibly by ground-water inflow from outside the area. Recharge is greatest in the uplands, where rainfall is heavy and where much infiltration takes place before rainwater collects in the middle and lower reaches of stream channels. Once water collects in and saturates the alluvium of stream channels, additional inflow to the streams will flow out to sea, only slightly decreased by seepage. Average annual direct runoff from the 90-square-mile Pearl Harbor area is 47.27 million gallons per day, or 11.1 inches; this is 13.3 percent of the average annual rainfall (83.3 in.) over the area. Average annual direct runoff in streams at the 800- and 400-foot altitudes is 29 and 38 million gallons per day, respectively. Kipapa Stream has the largest average annual direct runoff at those altitudes--6 and 9 million gallons per day, respectively. Because streams are flashy and have a wide range in discharge, only 60 percent of the average annual runoff can be economically diverted through ditches to recharge areas. The diversion may be increased slightly if reservoirs are used in conjunction with ditches to temporarily detain flows in excess of ditch capacity. The planned irrigation use of some of the perennial flow available in Waikele Stream near sea level will decrease pumping from and increase recharge to the basal aquifer. Suspended-sediment load is mainly silt and clay, and it increases rapidly with increased discharge. Thus, the use of streamflow for artificial recharge poses problems. High flows must be used if recharge is to be effective, but flows must not be so high as to cause clogging of recharge facilities with sediment or woodland debris. Practical tests are needed to determine the advantages and disadvantages of different types of recharge structures, such as a reservoir or basin, large-diameter deep shafts, deep wells, or combinations of all these structures.

  10. The problems of mass transfer and formation of deposits of corrosion products on fuel assemblies of a VVER-1200 reactor

    NASA Astrophysics Data System (ADS)

    Rodionov, Yu. A.; Kritskii, V. G.; Berezina, I. G.; Gavrilov, A. V.

    2014-03-01

    On the basis of examination of materials published both in Russia and abroad, as well as their own investigations, the authors explain the reasons for the occurrence of such effects as AOA (Axial Offset Anomalies) and an increase in the coolant pressure difference in the core of nuclear reactors of the VVER type. To detect the occurrence of the AOA effect, the authors suggest using the specific activity of 58Co in the coolant. In the VVER-1200 design the thermohydraulic regime for fuel assemblies in the first year of their service life involves slight boiling of the coolant in the upper part of the core, which may induce the occurrence of the AOA effect, intensification of corrosion of fuel claddings, and abnormal increase in deposition of corrosion products. Radiolysis of the water coolant in the boiling section (boiling in pores of deposits) may intensify not only general corrosion but also a localized (nodular) one. As a result of intensification of the corrosion processes and growth of deposits, deterioration of the radiation situation in the rooms of the primary circuit of a VVER-1200 reactor as compared to that at nuclear power plants equipped with reactors of the VVER-1000 type is possible. Recommendations for preventing the AOA effect at nuclear power plants with VVER-1200 reactors on the matter of the direction of further investigations are made.

  11. Growth of oxygen bubbles during recharge process in zinc-air battery

    NASA Astrophysics Data System (ADS)

    Wang, Keliang; Pei, Pucheng; Ma, Ze; Chen, Huicui; Xu, Huachi; Chen, Dongfang; Xing, Haoqiang

    2015-11-01

    Rechargeable zinc-air battery used for energy storage has a serious problem of charging capacity limited by oxygen bubble coalescence. Fast removal of oxygen bubbles adhered to the charging electrode surface is of great importance for improving the charging performance of the battery. Here we show that the law of oxygen bubble growth can be achieved by means of phase-field simulation, revealing two phenomena of bubble detachment and bubble coalescence located in the charging electrode on both sides. Hydrodynamic electrolyte and partial insulation structure of the charging electrode are investigated to solve the problem of oxygen bubble coalescence during charging. Two types of rechargeable zinc-air battery are developed on the basis of different tri-electrode configurations, demonstrating that the charging performance of the battery with electrolyte flow (Ⅰ) is better than that of the battery with the partially insulated electrode (Ⅱ), while the battery Ⅱ is superior to the battery Ⅰ in the discharging performance, cost and portability. The proposed solutions and results would be available for promoting commercial application of rechargeable zinc-air batteries or other metal-air batteries.

  12. Global synthesis of groundwater recharge in semiarid and arid regions

    USGS Publications Warehouse

    Scanlon, B.R.; Keese, K.E.; Flint, A.L.; Flint, L.E.; Gaye, C.B.; Edmunds, W.M.; Simmers, I.

    2006-01-01

    Global synthesis of the findings from ???140 recharge study areas in semiarid and arid regions provides important information on recharge rates, controls, and processes, which are critical for sustainable water development. Water resource evaluation, dryland salinity assessment (Australia), and radioactive waste disposal (US) are among the primary goals of many of these recharge studies. The chloride mass balance (CMB) technique is widely used to estimate recharge. Average recharge rates estimated over large areas (40-374000 km2) range from 0.2 to 35 mm year-1, representing 0.1-5% of long-term average annual precipitation. Extreme local variability in recharge, with rates up to ???720 m year-1, results from focussed recharge beneath ephemeral streams and lakes and preferential flow mostly in fractured systems. System response to climate variability and land use/land cover (LU/LC) changes is archived in unsaturated zone tracer profiles and in groundwater level fluctuations. Inter-annual climate variability related to El Nin??o Southern Oscillation (ENSO) results in up to three times higher recharge in regions within the SW US during periods of frequent El Nin??os (1977-1998) relative to periods dominated by La Nin??as (1941-1957). Enhanced recharge related to ENSO is also documented in Argentina. Climate variability at decadal to century scales recorded in chloride profiles in Africa results in recharge rates of 30 mm year-1 during the Sahel drought (1970-1986) to 150 mm year-1 during non-drought periods. Variations in climate at millennial scales in the SW US changed systems from recharge during the Pleistocene glacial period (??? 10 000 years ago) to discharge during the Holocene semiarid period. LU/LC changes such as deforestation in Australia increased recharge up to about 2 orders of magnitude. Changes from natural grassland and shrublands to dryland (rain-fed) agriculture altered systems from discharge (evapotranspiration, ET) to recharge in the SW US. The impact of LU change was much greater than climate variability in Niger (Africa), where replacement of savanna by crops increased recharge by about an order of magnitude even during severe droughts. Sensitivity of recharge to LU/LC changes suggests that recharge may be controlled through management of LU. In irrigated areas, recharge varies from 10 to 485 mm year-1, representing 1-25% of irrigation plus precipitation. However, irrigation pumpage in groundwater-fed irrigated areas greatly exceeds recharge rates, resulting in groundwater mining. Increased recharge related to cultivation has mobilized salts that accumulated in the unsaturated zone over millennia, resulting in widespread groundwater and surface water contamination, particularly in Australia. The synthesis of recharge rates provided in this study contains valuable information for developing sustainable groundwater resource programmes within the context of climate variability and LU/LC change. Copyright ?? 2006 John Wiley & Sons, Ltd.

  13. Advances of aqueous rechargeable lithium-ion battery: A review

    NASA Astrophysics Data System (ADS)

    Alias, Nurhaswani; Mohamad, Ahmad Azmin

    2015-01-01

    The electrochemical characteristic of the aqueous rechargeable lithium-ion battery has been widely investigated in efforts to design a green and safe technology that can provide a highly specific capacity, high efficiency and long life for high power applications such as the smart grid and electric vehicle. It is believed that the advantages of this battery will overcome the limitations of the rechargeable lithium-ion battery with organic electrolytes that comprise safety and create high fabrication cost issues. This review focuses on the opportunities of the aqueous rechargeable lithium-ion battery compared to the conventional rechargeable lithium-ion battery with organic-based electrolytes. Previously reported studies are briefly summarised, together with the presentation of new findings based on the conductivity, morphology, electrochemical performance and cycling stability results. The factors that influence the electrochemical performance, the challenges and potential of the aqueous rechargeable lithium-ion battery are highlighted in order to understand and maintained the excellent battery performance.

  14. Global synthesis of groundwater recharge in semiarid and arid regions

    NASA Astrophysics Data System (ADS)

    Scanlon, Bridget R.; Keese, Kelley E.; Flint, Alan L.; Flint, Lorraine E.; Gaye, Cheikh B.; Edmunds, W. Michael; Simmers, Ian

    2006-10-01

    Global synthesis of the findings from 140 recharge study areas in semiarid and arid regions provides important information on recharge rates, controls, and processes, which are critical for sustainable water development. Water resource evaluation, dryland salinity assessment (Australia), and radioactive waste disposal (US) are among the primary goals of many of these recharge studies. The chloride mass balance (CMB) technique is widely used to estimate recharge. Average recharge rates estimated over large areas (40-374 000 km2) range from 0.2 to 35 mm year-1, representing 0.1-5% of long-term average annual precipitation. Extreme local variability in recharge, with rates up to 720 m year-1, results from focussed recharge beneath ephemeral streams and lakes and preferential flow mostly in fractured systems. System response to climate variability and land use/land cover (LU/LC) changes is archived in unsaturated zone tracer profiles and in groundwater level fluctuations. Inter-annual climate variability related to El Niño Southern Oscillation (ENSO) results in up to three times higher recharge in regions within the SW US during periods of frequent El Niños (1977-1998) relative to periods dominated by La Niñas (1941-1957). Enhanced recharge related to ENSO is also documented in Argentina. Climate variability at decadal to century scales recorded in chloride profiles in Africa results in recharge rates of 30 mm year-1 during the Sahel drought (1970-1986) to 150 mm year-1 during non-drought periods. Variations in climate at millennial scales in the SW US changed systems from recharge during the Pleistocene glacial period (10 000 years ago) to discharge during the Holocene semiarid period. LU/LC changes such as deforestation in Australia increased recharge up to about 2 orders of magnitude. Changes from natural grassland and shrublands to dryland (rain-fed) agriculture altered systems from discharge (evapotranspiration, ET) to recharge in the SW US. The impact of LU change was much greater than climate variability in Niger (Africa), where replacement of savanna by crops increased recharge by about an order of magnitude even during severe droughts. Sensitivity of recharge to LU/LC changes suggests that recharge may be controlled through management of LU. In irrigated areas, recharge varies from 10 to 485 mm year-1, representing 1-25% of irrigation plus precipitation. However, irrigation pumpage in groundwater-fed irrigated areas greatly exceeds recharge rates, resulting in groundwater mining. Increased recharge related to cultivation has mobilized salts that accumulated in the unsaturated zone over millennia, resulting in widespread groundwater and surface water contamination, particularly in Australia. The synthesis of recharge rates provided in this study contains valuable information for developing sustainable groundwater resource programmes within the context of climate variability and LU/LC change.

  15. Groundwater recharge rate and zone structure estimation using PSOLVER algorithm.

    PubMed

    Ayvaz, M Tamer; Elçi, Alper

    2014-01-01

    The quantification of groundwater recharge is an important but challenging task in groundwater flow modeling because recharge varies spatially and temporally. The goal of this study is to present an innovative methodology to estimate groundwater recharge rates and zone structures for regional groundwater flow models. Here, the unknown recharge field is partitioned into a number of zones using Voronoi Tessellation (VT). The identified zone structure with the recharge rates is associated through a simulation-optimization model that couples MODFLOW-2000 and the hybrid PSOLVER optimization algorithm. Applicability of this procedure is tested on a previously developed groundwater flow model of the Tahtalı Watershed. Successive zone structure solutions are obtained in an additive manner and penalty functions are used in the procedure to obtain realistic and plausible solutions. One of these functions constrains the optimization by forcing the sum of recharge rates for the grid cells that coincide with the Tahtalı Watershed area to be equal to the areal recharge rate determined in the previous modeling by a separate precipitation-runoff model. As a result, a six-zone structure is selected as the best zone structure that represents the areal recharge distribution. Comparison to results of a previous model for the same study area reveals that the proposed procedure significantly improves model performance with respect to calibration statistics. The proposed identification procedure can be thought of as an effective way to determine the recharge zone structure for groundwater flow models, in particular for situations where tangible information about groundwater recharge distribution does not exist. PMID:23746002

  16. Improved Recharge Estimation from Portable, Low-Cost Weather Stations.

    PubMed

    Holländer, Hartmut M; Wang, Zijian; Assefa, Kibreab A; Woodbury, Allan D

    2016-03-01

    Groundwater recharge estimation is a critical quantity for sustainable groundwater management. The feasibility and robustness of recharge estimation was evaluated using physical-based modeling procedures, and data from a low-cost weather station with remote sensor techniques in Southern Abbotsford, British Columbia, Canada. Recharge was determined using the Richards-based vadose zone hydrological model, HYDRUS-1D. The required meteorological data were recorded with a HOBO(TM) weather station for a short observation period (about 1 year) and an existing weather station (Abbotsford A) for long-term study purpose (27 years). Undisturbed soil cores were taken at two locations in the vicinity of the HOBO(TM) weather station. The derived soil hydraulic parameters were used to characterize the soil in the numerical model. Model performance was evaluated using observed soil moisture and soil temperature data obtained from subsurface remote sensors. A rigorous sensitivity analysis was used to test the robustness of the model. Recharge during the short observation period was estimated at 863 and 816 mm. The mean annual recharge was estimated at 848 and 859 mm/year based on a time series of 27 years. The relative ratio of annual recharge-precipitation varied from 43% to 69%. From a monthly recharge perspective, the majority (80%) of recharge due to precipitation occurred during the hydrologic winter period. The comparison of the recharge estimates with other studies indicates a good agreement. Furthermore, this method is able to predict transient recharge estimates, and can provide a reasonable tool for estimates on nutrient leaching that is often controlled by strong precipitation events and rapid infiltration of water and nitrate into the soil. PMID:26011672

  17. Nanocarbon networks for advanced rechargeable lithium batteries.

    PubMed

    Xin, Sen; Guo, Yu-Guo; Wan, Li-Jun

    2012-10-16

    Carbon is one of the essential elements in energy storage. In rechargeable lithium batteries, researchers have considered many types of nanostructured carbons, such as carbon nanoparticles, carbon nanotubes, graphene, and nanoporous carbon, as anode materials and, especially, as key components for building advanced composite electrode materials. Nanocarbons can form efficient three-dimensional conducting networks that improve the performance of electrode materials suffering from the limited kinetics of lithium storage. Although the porous structure guarantees a fast migration of Li ions, the nanocarbon network can serve as an effective matrix for dispersing the active materials to prevent them from agglomerating. The nanocarbon network also affords an efficient electron pathway to provide better electrical contacts. Because of their structural stability and flexibility, nanocarbon networks can alleviate the stress and volume changes that occur in active materials during the Li insertion/extraction process. Through the elegant design of hierarchical electrode materials with nanocarbon networks, researchers can improve both the kinetic performance and the structural stability of the electrode material, which leads to optimal battery capacity, cycling stability, and rate capability. This Account summarizes recent progress in the structural design, chemical synthesis, and characterization of the electrochemical properties of nanocarbon networks for Li-ion batteries. In such systems, storage occurs primarily in the non-carbon components, while carbon acts as the conductor and as the structural buffer. We emphasize representative nanocarbon networks including those that use carbon nanotubes and graphene. We discuss the role of carbon in enhancing the performance of various electrode materials in areas such as Li storage, Li ion and electron transport, and structural stability during cycling. We especially highlight the use of graphene to construct the carbon conducting network for alloy anodes, such as Si and Ge, to accelerate electron transport, alleviate volume change, and prevent the agglomeration of active nanoparticles. Finally, we describe the power of nanocarbon networks for the next generation rechargeable lithium batteries, including Li-S, Li-O(2), and Li-organic batteries, and provide insights into the design of ideal nanocarbon networks for these devices. In addition, we address the ways in which nanocarbon networks can expand the applications of rechargeable lithium batteries into the emerging fields of stationary energy storage and transportation. PMID:22953777

  18. Artificial Recharge Coupled with Flood Mitigation in Jeju, Korea

    NASA Astrophysics Data System (ADS)

    Kim, Y.; Koo, M.; Lee, K.; Moon, D.; Barry, J. M.; Park, W.

    2010-12-01

    The primary goal of this study is to develop and apply the artificial recharge system at Han Stream in Jeju Island, Korea, for not only securing sustainable groundwater resources, but also mitigating severe floods occurred due to the global climate changes. Jeju-friendly Aquifer Recharge Technology (J-ART) in this study has been developed by capturing ephemeral stream water with no interference in the environments such as natural recharge or eco-system, storing the flood water in the reservoirs, recharging it through designed borehole after appropriate water treatment, and then making it to be used at down-gradient production wells. For optimal design of J-ART, we conducted injection tests at the monitoring well (MW5) as well as at the planned recharge site during drilling the recharge wells and performed a modeling with the data obtained. Based on the modeling results, the artificial recharge wells were developed with a design of 10-meter spacing between the wells and 35-40 meter depths, which has a capacity of more than 2,500,000 m3 of groundwater resources in a year. Characterizing groundwater flow from recharge area to discharge area should be achieved to assess the efficiency of J-ART. The resistivity logging employed to predict water flow in unsaturated zone during artificial recharge based on the inverse modeling and resistivity change patterns. Stable isotope studies of deuterium and oxygen-18 of surface waters and groundwaters were carried out to interpret mixing and flow in groundwaters impacted by artificial recharge. Transient models were developed to predict the effects of artificial recharge using the hydraulic properties of aquifers, groundwater levels, and meteorological data. Time series changes of water balance after artificial recharge were analyzed, and residence time of the recharged water was also predicted with a certain degree of uncertainty. Keywords: J-ART, Hydrogeological methods, Geophysical survey, Stable isotopes, Groundwater modeling, Jeju Island. Acknowledgements: This research was supported by a grant (code 3-2-3) from the Sustainable Water Resources Research Center of 21st Century Frontier Research Program.

  19. Polymer Energy Rechargeable System (PERS) Development Program

    NASA Technical Reports Server (NTRS)

    Baldwin, Richard S.; Manzo, Michelle A.; Dalton, Penni J.; Marsh, Richard A.; Surampudi, Rao

    2001-01-01

    The National Aeronautics and Space Administration (NASA) and the Air Force Research Laboratory (AFRL) have recently established a collaborative effort to support the development of polymer-based, lithium-based cell chemistries and battery technologies to address the next generation of aerospace applications and mission needs. The overall objective of this development program, which is referred to as PERS, Polymer Energy Rechargeable System, is to establish a world-class technology capability and U.S. leadership in polymer-based battery technology for aerospace applications. Programmatically, the PERS initiative will exploit both interagency collaborations to address common technology and engineering issues and the active participation of academia and private industry. The initial program phases will focus on R&D activities to address the critical technical issues and challenges at the cell level.

  20. Spinel electrodes for rechargeable lithium batteries.

    SciTech Connect

    Thackeray, M. M.

    1999-11-10

    This paper gives a historical account of the development of spinel electrodes for rechargeable lithium batteries. Research in the late 1970's and early 1980's on high-temperature . Li/Fe{sub 3}O{sub 4} cells led to the evaluation of lithium spinels Li[B{sub 2}]X{sub 4} at room temperature (B = metal cation). This work highlighted the importance of the [B{sub 2}]X{sub 4}spinel framework as a host electrode structure and the ability to tailor the cell voltage by selection of different B cations. Examples of lithium-ion cells that operate with spinel anode/spinel cathode couples are provided. Particular attention is paid to spinels within the solid solution system Li{sub 1+x}Mn{sub 2-x}O{sub 4} (0 {le} x {le} 0.33).

  1. Polymer Energy Rechargeable System Battery Being Developed

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle A.

    2003-01-01

    Long description. Illustrations of discotic liquid crystals, rod-coil polymers, lithium-ion conducting channel dilithium phthalocyanine (Li2Pc) from top and side, novel star polyethylene oxide structures, composite polyethylene oxide materials (showing polyethylene oxide + lithium salt, carbon atoms and oxygen atoms), homopolyrotaxanes, and diblock copolymers In fiscal year 2000, NASA established a program to develop the next generation, lithium-based, polymer electrolyte batteries for aerospace applications. The goal of this program, known as Polymer Energy Rechargeable Systems (PERS), is to develop a space-qualified, advanced battery system embodying polymer electrolyte and lithium-based electrode technologies and to establish world-class domestic manufacturing capabilities for advanced batteries with improved performance characteristics that address NASA s future aerospace battery requirements.

  2. Advanced rechargeable sodium batteries with novel cathodes

    NASA Technical Reports Server (NTRS)

    Distefano, S.; Ratnakumar, B. V.; Bankston, C. P.

    1989-01-01

    Various high energy density rechargeable batteries are being considered for future space applications. Of these, the sodium sulfur battery is one of the leading candidates. The primary advantage is the high energy density (760 Wh/kg theoretical). Energy densities in excess of 180 Wh/kg have been realized in practical batteries. More recently, cathodes other than sulfur are being evaluated. Researchers at JPL are evaluating various new cathode materials for use in high energy density sodium batteries for advanced space applications. The approach is to carry out basic electrochemical studies of these materials in a sodium cell configuration in order to understand their fundamental behaviors. Thus far studies have focused on alternate metal chlorides such as CuCl2 and organic cathode materials such as tetracyanoethylene (TCNE).

  3. Advanced rechargeable sodium batteries with novel cathodes

    NASA Technical Reports Server (NTRS)

    Di Stefano, S.; Ratnakumar, B. V.; Bankston, C. P.

    1990-01-01

    Various high energy density rechargeable batteries are being considered for future space applications. Of these, the sodium-sulfur battery is one of the leading candidates. The primary advantage is the high energy density (760 W h/kg theoretical). Energy densities in excess of 180 W h/kg have been realized in practical batteries. More recently, cathodes other than sulfur are being evaluated. Various new cathode materials are presently being evaluated for use in high energy density sodium batteries for advanced space applications. The approach is to carry out basic electrochemical studies of these materials in a sodium cell configuration in order to understand their fundamental behaviors. Thus far, the studies have focussed on alternative metal chlorides such as CuCl2 and organic cathode materials such as TCNE.

  4. High specific power lithium polymer rechargeable battery

    SciTech Connect

    Chu, M.Y.; De Jonghe, L.; Visco, S.

    1996-11-01

    PolyPlus Battery Company (PPBC) is developing an advanced lithium polymer rechargeable battery based on its proprietary positive electrode. This battery offers high steady-state (> 250 W/kg) and peak power densities (3,000 W/kg), in a low cost and environmentally benign format. This PolyPlus lithium polymer battery also delivers high specific energy. The first generation battery has an energy density of 100 Wh/kg (120 Wh/l) and subsequent generations increases the performance in excess of 500 Wh/kg (600 Wh/l). The high power and energy densities, along with the low toxicity and low cost of materials used in the PolyPlus solid-state cell makes this battery exceptionally attractive for both hybrid and electric vehicle applications.

  5. Simulation of the xerographic recharge process

    SciTech Connect

    Feng, Chang; Parker, S.E.; Lean, Meng H.

    1996-12-31

    Laser xerography (e.g. laser printing, photo-copying, etc.) involves the sequential steps: uniform charging of the photoconductor surface, discharging spots with a laser beam, developing the latent image on the photoconductor surface by the attachment of charged toner particles, and finally transfer-ring the image to paper through mechanical and electrostatic forces. Simulations have been developed that model these process from first-principles. Color reproduction involves multiple passes through these steps; once for each color separation (e.g. multiple toner layers on the photoconductor). Here we study the charging of the photoconductor surface, in situations of high mass-coverage with a 2D fluid model, and low mass coverage with a 3D particle model. Charge is sprayed using a corona, type discharge called a scorotron. We axe developing a 2D fluid model of the recharge process based on extending existing models. We use empirical IN data for the scorotron. A Boundary Integral Equation Method (BIEM) is used to solve for the field, and method of characteristics (MOC) to solve the charge continuity equation. Also developed, is a 3D particle model, where the field is solved using 3D BIEM and ionized air molecules axe treated as point charges which follow their average drift motion. Diffusion can be neglected because of the high voltage bias. Toner particles axe treated as finite size spherical dielectrics with nonuniform attached surface charge. We will show initial numerical results for both models. The purpose of this work is to develop a better understanding of how charge in transported through the toner layers in subsequent recharging during color laser xerography.

  6. Echo Meadows Project Winter Artificial Recharge.

    SciTech Connect

    Ziari, Fred

    2002-12-19

    This report discusses the findings of the Echo Meadows Project (BPA Project 2001-015-00). The main purpose of this project is to artificially recharge an alluvial aquifer, WITH water from Umatilla River during the winter high flow period. In turn, this recharged aquifer will discharge an increased flow of cool groundwater back to the river, thereby improving Umatilla River water quality and temperature. A considerable side benefit is that the Umatilla River should improve as a habitat for migration, spanning, and rearing of anadromous and resident fish. The scope of this project is to provide critical baseline information about the Echo Meadows and the associated reach of the Umatilla River. Key elements of information that has been gathered include: (1) Annual and seasonal groundwater levels in the aquifer with an emphasis on the irrigation season, (2) Groundwater hydraulic properties, particularly hydraulic conductivity and specific yield, and (3) Groundwater and Umatilla River water quality including temperature, nutrients and other indicator parameters. One of the major purposes of this data gathering was to develop input to a groundwater model of the area. The purpose of the model is to estimate our ability to recharge this aquifer using water that is only available outside of the irrigation season (December through the end of February) and to estimate the timing of groundwater return flow back to the river. We have found through the data collection and modeling efforts that this reach of the river had historically returned as much as 45 cubic feet per second (cfs) of water to the Umatilla River during the summer and early fall. However, this return flow was reduced to as low as 10 cfs primarily due to reduced quantities of irrigation application, gain in irrigation efficiencies and increased groundwater pumping. Our modeling indicated that it is possible to restore these critical return flows using applied water outside of the irrigation season. We further found that this water can be timed to return to the river during the desired time of the year (summer to early fall). This is because the river stage, which remains relatively high until this time, drops during the irrigation season-thereby releasing the stored groundwater and increasing river flows. A significant side benefit is that these enhanced groundwater return flows will be clean and cold, particularly as compared to the Umatilla River. We also believe that this same type of application of water could be done and the resulting stream flows could be realized in other watersheds throughout the Pacific Northwest. This means that it is critical to compare the results from this baseline report to the full implementation of the project in the next phase. As previously stated, this report only discusses the results of data gathered during the baseline phase of this project. We have attempted to make the data that has been gathered accessible with the enclosed databases and spreadsheets. We provide computer links in this report to the databases so that interested parties can fully evaluate the data that has been gathered. However, we cannot emphasize too strongly that the real value of this project is to implement the phases to come, compare the results of these future phases to this baseline and develop the science and strategies to successfully implement this concept to other rivers in the Pacific Northwest. The results from our verified and calibrated groundwater model matches the observed groundwater data and trends collected during the baseline phase. The modeling results indicate that the return flows may increase to their historic values with the addition of 1 acre-ft/acre of recharge water to the groundwater system (about 9,600 acre-feet total). What this means is that through continued recharge project, you can double to quadruple the annual baseflow of the Umatilla River during the low summer and fall flow periods as compared to the present base-flow. The cool and high quality recharge water is a significant beneficial impact to the river system.

  7. Rapid recharge capability of valve-regulated lead-acid batteries for electric vehicle and hybrid electric vehicle applications

    NASA Astrophysics Data System (ADS)

    Fleming, F. A.; Shumard, P.; Dickinson, B.

    Range limitation is a significant drawback to the successful commercialization of electric vehicles (EVs). An apt description of an EV is `a high performance vehicle with a one-gallon fuel tank'. In the absence of a `super battery', there are at least two approaches to resolving this drawback. The first approach is rapid recharge, i.e., recharging the battery as close as possible to the same time period as it takes to fill the petrol tank of an internal-combustion-engined (ICE) vehicle. Whilst not extending the vehicle range as such, this approach does enable high usage of the vehicle without experiencing unduly long recharge times. The ability of the battery to accept rapid recharge is paramount for this approach. The second approach is the development of a hybrid electric vehicle (HEV). In this case, the demand on the battery is the ability to provide, and also absorb from regenerative braking, high specific peak-power levels over a wide range of battery state-of-charge. This paper describes the ability, and indeed limitations, of the valve-regulated Genesis® lead-acid battery in meeting such requirements.

  8. NEACRP standard problem exercise on criticality codes for dissolving fissile oxides in acids: A reference method for treating the fuel double heterogeneity

    SciTech Connect

    Santamarina, A.; Smith, H.J. . Div. d'Etudes et de Developpement des Reacteurs); Whitesides, G.E. )

    1990-01-01

    The value of international comparison studies by the OECD-NEA Criticality Working Group has again been demonstrated by this study. Computational methods that had been commonly used for criticality safety calculations and which were shown to be valid for systems for which experimental data existed, were demonstrated to be inadequate when extrapolated to some simulated actual situations. The major source of dispersion in the results in international criticality benchmark calculations on problems treating a fuel double heterogeneity is shown to be the incorrect evaluation of effective resonance cross sections for 238U. A reference calculational method is proposed and used to evaluate theoretically the errors created by various standard methods of calculating the effects of self-shielding of resonance cross sections. 7 figs., 3 tabs.

  9. Geostatistical estimates of future recharge for the Death Valley region

    SciTech Connect

    Hevesi, J.A.; Flint, A.L.

    1998-12-01

    Spatially distributed estimates of regional ground water recharge rates under both current and potential future climates are needed to evaluate a potential geologic repository for high-level nuclear waste at Yucca Mountain, Nevada, which is located within the Death Valley ground-water region (DVGWR). Determining the spatial distribution of recharge is important for regional saturated-zone ground-water flow models. In the southern Nevada region, the Maxey-Eakin method has been used for estimating recharge based on average annual precipitation. Although this method does not directly account for a variety of location-specific factors which control recharge (such as bedrock permeability, soil cover, and net radiation), precipitation is the primary factor that controls in the region. Estimates of recharge obtained by using the Maxey-Eakin method are comparable to estimates of recharge obtained by using chloride balance studies. The authors consider the Maxey-Eakin approach as a relatively simple method of obtaining preliminary estimates of recharge on a regional scale.

  10. [Effects of reclaimed water recharge on groundwater quality: a review].

    PubMed

    Chen, Wei-Ping; Lü, Si-Dan; Wang, Mei-E; Jiao, Wen-Tao

    2013-05-01

    Reclaimed water recharge to groundwater is an effective way to relieve water resource crisis. However, reclaimed water contains some pollutants such as nitrate, heavy metals, and new type contaminants, and thus, there exists definite environmental risk in the reclaimed water recharge to groundwater. To promote the development of reclaimed water recharge to groundwater and the safe use of reclaimed water in China, this paper analyzed the relevant literatures and practical experiences around the world, and summarized the effects of different reclaimed water recharge modes on the groundwater quality. Surface recharge makes the salt and nitrate contents in groundwater increased but the risk of heavy metals pollution be smaller, whereas well recharge can induce the arsenic release from sedimentary aquifers, which needs to be paid more attention to. New type contaminants are the hotspots in current researches, and their real risks are unknown. Pathogens have less pollution risks on groundwater, but some virus with strong activity can have the risks. Some suggestions were put forward to reduce the risks associated with the reclaimed water recharge to groundwater in China. PMID:24015541

  11. Quantifying the modern recharge of the "fossil" Sahara aquifers

    NASA Astrophysics Data System (ADS)

    GonçAlvèS, J.; Petersen, J.; Deschamps, P.; Hamelin, B.; Baba-Sy, O.

    2013-06-01

    The North-Western Sahara Aquifer System (NWSAS), one of the world's largest groundwater systems, shows an overall piezometric decline associated with increasing withdrawals. Estimating the recharge rate in such a semiarid system is challenging but crucial for sustainable water development. In this paper, the recharge of the NWSAS is estimated using a regional water budget based on GRACE terrestrial water storage monthly records, soil moisture from the GLDAS (a land data system that assimilates hydrological information), and groundwater pumping rates. A cumulated natural recharge rate of 1.40 ± 0.90 km3 yr-1is estimated for the two main aquifers. Our results suggest a renewal rate of about 40% which partly contradicts the premise that recharge in this area should be very low or even null. Aquifer depletion inferred from our analysis is consistent with observed piezometric head decline in the two main aquifers in the region. Annual recharge variations were also estimated and vary between 0 and 4.40 km3 yr-1for the period 2003-2010. These values correspond to a recharge between 0 and 6.75 mm yr-1 on the 650,000 km2of outcropping areas of the aquifers, which is consistent with the expected weak and sporadic recharge in this semiarid environment. These variations are also in line with annual rainfall variation with a lag time of about 1 year.

  12. Effects of artificial recharge on the Ogallala aquifer, Texas

    USGS Publications Warehouse

    Brown, Richmond Flint; Keys, W.S.

    1985-01-01

    Four recharge tests were conducted by injecting water from playa lakes through wells into the Ogallala Formation. Injection was by gravity flow and by pumping under pressure. At one site, 34-acre feet of water was injected by gravity and produced a significant increase in yield of the well. At a second site, gravity injection of only 0.58 acre-foot caused a significant decrease in permeability due to plugging by suspended sediment. At two other sites, injection by pumping 6 and 14 acre-feet respectively, resulted in discharge of water at the surface and in perching of water above the water table. Differences in success of recharge were largely due to aquifer lithology and, therefore, the type of permeability; the concentration of suspended solids in the recharge water; and the injection technique. The injection technique can be controlled and the concentration of suspended solids can be minimized by treatment, but the site for well recharge will accept water most rapidly if it is selected on the basis of a favorable geohydrologic environment. Geophysical logs were used to study the effect of aquifer lithology on recharge and to understand the movement of injected water. Temperature logs were particularly useful in tracing the movement of recharged water. Natural-gamma, gamma-gamma, and neutron logs provided important data on lithology and porosity in the aquifer and changes in porosity and water distribution resulting from recharge. Effective recharge of the Ogallala Formation, using water from playa lakes, is possible where geohydrologic conditions are favorable and the recharge system is properly constructed.

  13. Technical Note: Three-dimensional transient groundwater flow due to localized recharge with an arbitrary transient rate in unconfined aquifers

    NASA Astrophysics Data System (ADS)

    Chang, C.-H.; Huang, C.-S.; Yeh, H.-D.

    2015-11-01

    Most previous solutions for groundwater flow induced by localized recharge assumed either aquifer incompressibility or two-dimensional flow in the absence of the vertical flow. This paper develops a new three-dimensional flow model for hydraulic head variation due to localized recharge in a rectangular unconfined aquifer with four boundaries under the Robin condition. A governing equation for describing the head distribution is employed. The first-order free surface equation with a source term defining a constant recharge rate over a rectangular area is used to depict water table movement. The solution of the model for the head distribution is developed by the methods of the Laplace transform and double integral transform. Based on the convolution technique, the present solution is applicable to flow problems accounting for arbitrary time-depending recharge rates. The solution of depth-average head can then be obtained by integrating the head solution to depth and dividing the result by the aquifer thickness. The use of rectangular aquifer domain has two merits. One is that the integration for estimating the depth-average head can be analytically achieved. The other is that existing solutions based on aquifers of infinite extent can be considered as special cases of the present solution before the time having the aquifer boundary effect on the head distribution. With the help of the present solution, the assumption of neglecting the vertical flow effect on the transient head at an observation well outside a recharge region can be assessed by a dimensionless parameter related to the aquifer horizontal and vertical hydraulic conductivities, initial aquifer thickness, and a shortest distance between the observation well and the edge of the recharge region. The validity of assuming aquifer incompressibility is dominated by the ratio of the aquifer specific yield to its storage coefficient. In addition, the sensitivity analysis is performed to investigate the head response to the change in each of the aquifer parameters.

  14. Technical Note: Three-dimensional transient groundwater flow due to localized recharge with an arbitrary transient rate in unconfined aquifers

    NASA Astrophysics Data System (ADS)

    Chang, Chia-Hao; Huang, Ching-Sheng; Yeh, Hund-Der

    2016-03-01

    Most previous solutions for groundwater flow induced by localized recharge assumed either aquifer incompressibility or two-dimensional flow in the absence of the vertical flow. This paper develops a new three-dimensional flow model for hydraulic head variation due to localized recharge in a rectangular unconfined aquifer with four boundaries under the Robin condition. A governing equation describing spatiotemporal head distributions is employed. The first-order free-surface equation with a source term defining a constant recharge rate over a rectangular area is used to depict water table movement. The solution to the model for the head is developed with the methods of Laplace transform and double-integral transform. Based on Duhamel's theorem, the present solution is applicable to flow problems accounting for arbitrary time-dependent recharge rates. The solution to depth-average head can then be obtained by integrating the head solution to elevation and dividing the result by the aquifer thickness. The use of a rectangular aquifer domain has two merits. One is that the integration for estimating the depth-average head can be analytically achieved. The other is that existing solutions based on aquifers of infinite extent can be considered as special cases of the present solution before the time when the aquifer boundary had an effect on head predictions. With the help of the present solution, the assumption of neglecting the vertical flow effect on the temporal head distribution at an observation point outside a recharge region can be assessed by a dimensionless parameter related to the aquifer horizontal and vertical hydraulic conductivities, initial aquifer thickness, and the shortest distance between the observation point and the edge of the recharge region. The validity of assuming aquifer incompressibility is dominated by the ratio of the aquifer specific yield to its storage coefficient. In addition, a sensitivity analysis is performed to investigate the head response to the change in each of the aquifer parameters.

  15. Using Green and Ampt with Redistribution to Simulate Recharge for Saturated Groundwater Modeling in Support of Surface Water Applications

    NASA Astrophysics Data System (ADS)

    Downer, C. W.

    2003-12-01

    The Gridded Surface Subsurface Hydrologic Analysis Model (GSSHA) employs a one-dimensional finite difference approximation of the head based form of Richards' equation to calculate groundwater recharge for saturated groundwater simulations needed for groundwater/surface water interaction studies. When used to simulate sharp wetting fronts, solution of Richards' equation can be computationally very expensive. This computational cost may not be justified if Richards' equation is being solved merely to provide estimates of groundwater recharge for saturated groundwater simulations. For large problems, the computational cost may preclude the used of automated calibration methods which allow a more complete exploration of the parameter space but may require hundreds of simulations to do so. In addition to the Richards' equation solution the GSSHA model also includes Green and Ampt based infiltration models. These Green and Ampt approaches have historically been used to compute infiltration under Hortonian conditions, where saturated groundwater has little influence on surface water flows. It is hypothesized that the Green and Ampt based method of computing infiltration may prove adequate for computing groundwater recharge for use in saturated groundwater simulations. The GSSHA model is modified to allow the Green and Ampt with Redistribution model of infiltration to provide values of groundwater recharge for saturated groundwater simulations. The formulation results in infiltrated water immediately becoming recharge. The modified model is employed in two studies where groundwater surface water interaction is critical to the prediction of stream flow. In both cases the model is able to produce acceptable results in terms of predicting stream flow. The method appears useful for determining values of groundwater recharge for use with saturated groundwater simulations. The reduced simulation times with the method make the use of automated calibration methods possible.

  16. Recharge and discharge calculations to characterize the groundwater hydrologic balance

    SciTech Connect

    Liddle, R.G.

    1998-12-31

    Several methods are presented to quantify the ground water component of the hydrologic balance; including (1) hydrograph separation techniques, (2) water budget calculations, (3) spoil discharge techniques, and (4) underground mine inflow studies. Stream hydrograph analysis was used to calculate natural groundwater recharge and discharge rates. Yearly continuous discharge hydrographs were obtained for 16 watersheds in the Cumberland Plateau area of Tennessee. Baseflow was separated from storm runoff using computerized hydrograph analysis techniques developed by the USGS. The programs RECESS, RORA, and PART were used to develop master recession curves, calculate ground water recharge, and ground water discharge respectively. Station records ranged from 1 year of data to 60 years of data with areas of 0.67 to 402 square miles. Calculated recharge ranged from 7 to 28 inches of precipitation while ground water discharge ranged from 6 to 25 inches. Baseflow ranged from 36 to 69% of total flow. For sites with more than 4 years of data the median recharge was 20 inches/year and the 95% confidence interval for the median was 16.4 to 23.8 inches of recharge. Water budget calculations were also developed independently by a mining company in southern Tennessee. Results showed about 19 inches of recharge is available on a yearly basis. A third method used spoil water discharge measurements to calculate average recharge rate to the mine. Results showed 21.5 inches of recharge for this relatively flat area strip mine. In a further analysis it was shown that premining soil recharge rates of 19 inches consisted of about 17 inches of interflow and 2 inches of deep aquifer recharge while postmining recharge to the spoils had almost no interflow component. OSM also evaluated underground mine inflow data from northeast Tennessee and southeast Kentucky. This empirical data showed from 0.38 to 1.26 gallons per minute discharge per unit acreage of underground workings. This is the equivalent to 7 to 24 inches of recharge per year. The four methods provide a good comparative way to quantify the groundwater portion of the hydrologic balance.

  17. A solution to the problem of optimizing the fuel bias for a liquid propellant rocket by an application of the central limit theorem

    NASA Technical Reports Server (NTRS)

    Viera, W. J.

    1974-01-01

    A method of determining the fuel bias for a bipropellant liquid rocket that minimizes outage associated penalties on payload potential is presented. A fuel bias so derived is normally called the optimum fuel bias. The subjects discussed are: (1) probability density function of outage, (2) computer program listing, and (3) choosing the optimum fuel bias.

  18. A comparison of single-continuum and dual-conductivity karst aquifer models during recharge events

    NASA Astrophysics Data System (ADS)

    Saller, S. P.; Ronayne, M. J.

    2011-12-01

    Modeling groundwater flow through karst aquifers is a complex problem due to the heterogeneous, dual porosity nature of carbonate formations. This has limited the practice of transport modeling in regions dependent on karst aquifers, and created a need to explore new modeling techniques to address the issue. In this modeling study, we simulate flow in synthetic karst systems that contain stochastically generated conduit networks. For a variety of network geometries, dual-conductivity model simulations are performed using the conduit flow process in MODFLOW. This approach allows for the simulation of turbulent flow, pipe roughness and tortuosity, and matrix-conduit fluid exchange, permitting the development of realistic transient flow systems in response to recharge events. For each conduit network, a corresponding equivalent porous media (single-continuum) model is constructed by assigning representative high hydraulic conductivity values along the conduits. Both model systems were run using identical transient recharge events. The model comparison considers spring discharge at the network outlet, as well as simulated heads throughout the domain. Using the dual-conductivity model as the objective, conduit hydraulic conductivities were adjusted in the single-continuum model. Results indicate that the suitability of the single-continuum approach depends on the magnitude and location of recharge relative to the conduit network.

  19. Delineating spring recharge areas in a fractured sandstone aquifer (Luxembourg) based on pesticide mass balance

    NASA Astrophysics Data System (ADS)

    Farlin, J.; Drouet, L.; Gallé, T.; Pittois, D.; Bayerle, M.; Braun, C.; Maloszewski, P.; Vanderborght, J.; Elsner, M.; Kies, A.

    2013-06-01

    A simple method to delineate the recharge areas of a series of springs draining a fractured aquifer is presented. Instead of solving the flow and transport equations, the delineation is reformulated as a mass balance problem assigning arable land in proportion to the pesticide mass discharged annually in a spring at minimum total transport cost. The approach was applied to the Luxembourg Sandstone, a fractured-rock aquifer supplying half of the drinking water for Luxembourg, using the herbicide atrazine. Predictions of the recharge areas were most robust in situations of strong competition by neighbouring springs while the catchment boundaries for isolated springs were extremely sensitive to the parameter controlling flow direction. Validation using a different pesticide showed the best agreement with the simplest model used, whereas using historical crop-rotation data and spatially distributed soil-leaching data did not improve predictions. The whole approach presents the advantage of integrating objectively information on land use and pesticide concentration in spring water into the delineation of groundwater recharge zones in a fractured-rock aquifer.

  20. Recharge estimation in a large semi-arid basin using storage - discharge relationships

    NASA Astrophysics Data System (ADS)

    Bulovic, Nena; Larsen, Joshua; Reading, Lucy; McIntyre, Neil; Jarihani, Abdollah; Sabburg, Letitia; Undershultz, Jim

    2015-04-01

    The characteristics of flow recession in the absence of precipitation have long been used to infer upstream catchment storage properties. An intriguing aspect of this storage - discharge relationship occurs when changes in flow recession occur following a rainfall event due to increased storage. The main assumption in this case is that additional groundwater recharge has increased the storage within flow systems connected to the stream, which is then reflected in the increased recessional flow. Using flow records from 4 catchments (~100 km2) across the headwaters of the semi-arid Condamine Basin (and the unconfined section of the Surat artesian groundwater basin) within central eastern Australia, we evaluate and compare storage -discharge relationships and the change in storage for large individual events. Converting this to recharge resulted in low values compared to a number of independent recharge estimation techniques (chloride mass balance, water balance, groundwater hydrograph analysis). This discrepancy may arise because of some inherent differences between the techniques, however some important assumptions in the storage - discharge analysis are worth exploring. These include: the impact of evapotranspiration (ET) on the flow recession, which is largely unaccounted for, and is likely to be significant in semi-arid environments, and the bias towards larger events within the analysis, which is related to the difficulty associated with incorporating the large number of small events within automated time series analysis. We propose accounting for these limitations through the inclusion of remote sensing based ET estimates, and the use of multiple automated hydrograph separation techniques in extracting flow recession periods for analysis, and preferably those with lower user subjectivity. Overcoming these limitations is essential if catchment storage - discharge analysis techniques are to be more broadly applied to groundwater recharge estimation problems, especially in data poor semi-arid areas where the need for a better understanding of available water resources is only increasing.

  1. Using natural distributions of short-lived radium isotopes to quantify groundwater discharge and recharge

    USGS Publications Warehouse

    Krest, J.M.; Harvey, J.W.

    2003-01-01

    Radium activity in pore water of wetland sediments often differs from the amount expected from local production, decay, and exchange with solid phases. This disequilibrium results from vertical transport of radium with groundwater that flows between the underlying aquifer and surface water. In situations where groundwater recharge or discharge is significant, the rate of vertical water flow through wetland sediment can be determined from the radium disequilibrium by a combined model of transport, production, decay, and exchange with solid phases. We have developed and tested this technique at three sites in the freshwater portion of the Everglades by quantifying vertical advective velocities in areas with persistent groundwater recharge or discharge and estimating a coefficient of dispersion at a site that is subject to reversals between recharge and discharge. Groundwater velocities (v) were determined to be between 0 and -0.5 cm d-1 for a recharge site and 1.5 ?? 0.4 cm d-1 for a discharge site near Levee 39 in the Everglades. Strong gradients in 223Ra and 224Ra usually occurred at the base of the peat layer, which avoided the problems of other tracers (e.g., chloride) for which greatest sensitivity occurs near the peat surface - a zone readily disturbed by processes unrelated to groundwater flow. This technique should be easily applicable to any wetland system with different production rates of these isotopes in distinct sedimentary layers or surface water. The approach is most straightforward in systems where constant pore-water ionic strength can be assumed, simplifying the modeling of radium exchange.

  2. Current state, problems, and prospects of development of the fuel and power industry of the Russian Federation

    SciTech Connect

    Shatalov, A.T.

    1994-09-01

    Despite the political and territorial changes that have occurred in the former USSR, the Russian Federation as before remains the core of the entire energy supply system of countries of the Commonwealth of Independent States (CIS), the three Baltic States, as well as an exporter of oil and gas to European countries. Demonstrated gas reserves in Russia amount to 47 trillion cubic meters and coal reserves more than 200 billion tons. With the dissolution of the USSR, the infrastructure of the entire region was affected. The main production of pipes remained in Ukraine and 80% of the production of oil equipment remained in Azerbaijan. The majority of underground gas storage facilities, refineries, and electric-power installations constructed during the past 20 years remained in Belarus, Baltic Countries, and Ukraine. To solve some of the problems, laws were passed that aimed at the formation of market relations in the economy and power industry. The transition to a market economy in the oil and gas industry should take 5-7 years and has a large effect on the overall markets reforms taking place. The article also outlines the history and present state of petroleum reserves and development in Russia.

  3. ENGINEERING ECONOMIC ANALYSIS OF A PROGRAM FOR ARTIFICIAL GROUNDWATER RECHARGE.

    USGS Publications Warehouse

    Reichard, Eric G.; Bredehoeft, John D.

    1984-01-01

    This study describes and demonstrates two alternate methods for evaluating the relative costs and benefits of artificial groundwater recharge using percolation ponds. The first analysis considers the benefits to be the reduction of pumping lifts and land subsidence; the second considers benefits as the alternative costs of a comparable surface delivery system. Example computations are carried out for an existing artificial recharge program in Santa Clara Valley in California. A computer groundwater model is used to estimate both the average long term and the drought period effects of artificial recharge in the study area. Results indicate that the costs of artificial recharge are considerably smaller than the alternative costs of an equivalent surface system. Refs.

  4. GROUNDWATER RECHARGE/DISCHARGE, NEUSE RIVER WATERSHED, NC

    EPA Science Inventory

    The North Carolina Department of Environment and Natural Resources, Division of Water Quality and Groundwater Section, in cooperation with the NC Center for Geographic Information and Analysis, developed the Groundwater Recharge/Discharge digital data to enhance planning, siting ...

  5. Improved zinc electrode and rechargeable zinc-air battery

    DOEpatents

    Ross, P.N. Jr.

    1988-06-21

    The invention comprises an improved rechargeable zinc-air cell/battery having recirculating alkaline electrolyte and a zinc electrode comprising a porous foam support material which carries the active zinc electrode material. 5 figs.

  6. NTS groundwater recharge study, FY 1992. Data report

    SciTech Connect

    Lyles, B F; Mihevc, T M

    1992-10-01

    Groundwater recharge from precipitation is thought by many scientists to be extremely low in Southem Nevada; however, no direct measurements of recharge have been made to substantiate this hypothesis. Three geomorphic regions have been identified as potential areas of groundwater recharge at the Nevada Test Site (NTS): mesas, washes, and lowlands. Eight recharge monitoring stations have been installed to monitor each of these regions; four of the stations are on Pahute/Rainier Mesa, two stations are in Fortymile Wash, one station is in a transition area between the mesas and the lowlands (Whiterock Spring), and one station is located in Yucca Flat at the bottom of the U-3fd crater. An additional station is proposed for Frenchman Flat near the Area 5 mixed waste facility; however, the instrumentation of that site has been delayed due to the complex permitting process associated with instrument installation near the mixed waste facility. Digital data were collected from eight sites during FY 1992.

  7. Bipolar rechargeable lithium battery for high power applications

    NASA Technical Reports Server (NTRS)

    Hossain, Sohrab; Kozlowski, G.; Goebel, F.

    1993-01-01

    Viewgraphs of a discussion on bipolar rechargeable lithium battery for high power applications are presented. Topics covered include cell chemistry, electrolytes, reaction mechanisms, cycling behavior, cycle life, and cell assembly.

  8. Processes, Controls, and Potential for In-situ Nutrient Removal During Managed Aquifer Recharge in an Agricultural Basin

    NASA Astrophysics Data System (ADS)

    Schmidt, C. M.; Fisher, A. T.; Los Huertos, M.; Lockwood, B.

    2008-12-01

    We are conducting research on rates and dynamics of water quality improvement that occur during managed aquifer recharge (MAR), with a focus on reducing the load of nitrate exported during recharge. Nitrate is the most common nonpoint source pollutant in surface and ground water in the United States, and is a problem particularly in basins developed for agriculture. Our study site is located in central coastal California, where diversion from a slough (wetland) is permitted during periods of high flow for use in MAR. Diverted water is recharged into an eolian and fluvial, unconfined aquifer using a 3-km2 percolation pond, then subsequently recovered and distributed to local farmers. As a result of agricultural and other activities in the basin, diverted slough water is often rich in nitrate (historical values as high as 4 mM); similarly high nitrate values have been measured in water from the underlying aquifer. Prior to the start of the 2007-08 water year, we surveyed, sampled, and instrumented the recharge pond in order to quantify local seepage rates and sample recharging water to assess changes in water quality during infiltration through the base of the pond. Nests of piezometers and lysimeters were screened at depths of 50 to 150 cm beneath the base of the pond and sampled weekly throughout the recharge season. Total MAR was 7.4 × 105 m3 (600 ac-ft) during the 2007-08 water year, with initial nitrate concentrations of 10 μM to 100 μM in the diverted water. Point-specific infiltration rates were greater than 10 m/day in some locations below the pond, and much lower in other locations. Nitrate concentrations were reduced by 50 to 90% beneath the pond, with the greatest reductions occurring at lower concentrations and slower infiltration rates. Suboxic conditions developed beneath the pond during recharge, which is consistent with removal of nitrate by denitrification. Dissolved organic carbon concentrations were elevated during the recharge season throughout much of the shallow subsurface, suggesting that there is no carbon limitation on denitrification. Isotopic analyses will be used to determine the extent and dynamics of denitrification in this system, and to explore controls and pathways responsible for improvements to water quality.

  9. Spatial and temporal variations in seepage during managed aquifer recharge

    NASA Astrophysics Data System (ADS)

    Racz, A. J.; Fisher, A. T.; Schmidt, C. M.; Lockwood, B. S.; Los Huertos, M.

    2009-12-01

    Managed aquifer recharge (MAR) is an increasingly important means of supplementing fresh water resources and helping to limit ground water overdraft. Many MAR systems are operated above a vadose zone and usually recharge rapidly during an initial phase of diversion. Recharge typically slows considerably within subsequent weeks to months as sedimentation, biofouling, soil compaction, drainage at the base of the wetting front, and other processes reduce the hydraulic conductance below the percolation pond. Studies of such systems provide controlled windows into subsurface conditions and processes, vital both for improving MAR efficiency and generating better understanding of recharge processes in general. We instrumented a 3 ha MAR pond above a shallow aquifer in central coastal California, to quantify variations in rates and locations of recharge, and to measure changes in soil properties with time during a recharge season. Using heat as a tracer of fluid flow, we utilize data recorded by autonomous temperature loggers installed in the base of the pond to calculate point-specific seepage rates based on time-series analysis. Pressure loggers installed in the same locations allow quantification of head gradients with time. By combining gradient and seepage data, we determine absolute values of the hydraulic conductance of the saturated soil at the base of the pond, including changes in these values with time. Point-specific seepage rates vary enormously throughout the recharge cycle and across the pond base. Areas with rapid initial seepage rates exceeding 5 m d-1 decrease abruptly to <0.1 m d-1 after the first few weeks of MAR operation. Conversely, seepage rates in areas which are virtually stagnant at the onset of recharge increase to >0.5 m d-1 after several months, accounting for the majority of late-season recharge. In effect, the locus of seepage assumes the form of a kinematic wave as it propagates laterally with time across the pond bed. Seepage appears to correlate with soil type, with areas of initial rapid seepage corresponding to more coarsely grained soils, and later recharge occurring in areas overlying significantly finer material. Collection of soil samples before and after the seepage season, as well as geochemical data from the aquifer below the pond, help to resolve the fraction of the pond, and hence the subsurface conditions, that contribute most to recharge.

  10. Cryogenic Transport of High-Pressure-System Recharge Gas

    NASA Technical Reports Server (NTRS)

    Ungar, Eugene K,; Ruemmele, Warren P.; Bohannon, Carl

    2010-01-01

    A method of relatively safe, compact, efficient recharging of a high-pressure room-temperature gas supply has been proposed. In this method, the gas would be liquefied at the source for transport as a cryogenic fluid at or slightly above atmospheric pressure. Upon reaching the destination, a simple heating/expansion process would be used to (1) convert the transported cryogenic fluid to the room-temperature, high-pressure gaseous form in which it is intended to be utilized and (2) transfer the resulting gas to the storage tank of the system to be recharged. In conventional practice for recharging high-pressure-gas systems, gases are transported at room temperature in high-pressure tanks. For recharging a given system to a specified pressure, a transport tank must contain the recharge gas at a much higher pressure. At the destination, the transport tank is connected to the system storage tank to be recharged, and the pressures in the transport tank and the system storage tank are allowed to equalize. One major disadvantage of the conventional approach is that the high transport pressure poses a hazard. Another disadvantage is the waste of a significant amount of recharge gas. Because the transport tank is disconnected from the system storage tank when it is at the specified system recharge pressure, the transport tank still contains a significant amount of recharge gas (typically on the order of half of the amount transported) that cannot be used. In the proposed method, the cryogenic fluid would be transported in a suitably thermally insulated tank that would be capable of withstanding the recharge pressure of the destination tank. The tank would be equipped with quick-disconnect fluid-transfer fittings and with a low-power electric heater (which would not be used during transport). In preparation for transport, a relief valve would be attached via one of the quick-disconnect fittings (see figure). During transport, the interior of the tank would be kept at a near-ambient pressure far below the recharge pressure. As leakage of heat into the tank caused vaporization of the cryogenic fluid, the resulting gas would be vented through the relief valve, which would be set to maintain the pressure in the tank at the transport value. Inasmuch as the density of a cryogenic fluid at atmospheric pressure greatly exceeds that of the corresponding gas in a practical high-pressure tank at room temperature, a tank for transporting a given mass of gas according to the proposed method could be smaller (and, hence, less massive) than is a tank needed for transporting the same mass of gas according to the conventional method.

  11. Investigation of artificial recharge of aquifers in Nebraska

    USGS Publications Warehouse

    Lichtler, William F.; Stannard, David I.; Kouma, Edwin

    1980-01-01

    Progressive declines of ground-water levels in some areas of Nebraska prompted this investigation into the technical feasibility of recharging aquifers through wells, impoundments, pits, and canals. Information gained from a literature search and from preliminary tests was used to design several artificial-recharge experiments in Nebraska from 1977 to 1979. In well experiments, 0.46 billion gallons of water from an aquifer recharged by the Platte River was transported by pipeline and injected through a well into a sand and gravel aquifer near Aurora. Recharge was at about 730 gallons per minute during tests of 6- and 8-months duration. No evidence of clogging of the aquifer due to chemical reactions, air entrainment, or bacteria was detected in either test. In the 6-month test, evidence of clogging due to fine sediment in the recharge water was detected; however, analysis of this test indicated that recharge could have continued for several years before rehabilitation would have become necessary. Results of the 8-month test confirmed results of the earlier test until casing failure in the supply well and subsequent sediment deposition in the recharge well caused rapid water-level rise in the recharge well. In surface-spreading experiments, maximum infiltration rates from 24-foot-diameter ring infiltrometers near Aurora and Tryon were 0.4 and 11 feet per day, respectively. Results indicate that large-scale surface spreading is feasible only where low-permeability layers are absent in the subsurface. Infiltration rates from reuse pits ranged from 0.01 to 1.6 feet per day, indicating highly variable subsurface permeability. Flow measurements in an irrigation canal near Farwell indicate an infiltration rate of 0.37 feet per day. (USGS)

  12. Statistical Method for Identification of Potential Groundwater Recharge Zone

    NASA Astrophysics Data System (ADS)

    Banerjee, Pallavi; Singh, V. S.

    2010-05-01

    The effective development of groundwater resource is essential for a country like India. Artificial recharge is the planned, human activity of augmenting the amount of groundwater available through works designed to increase the natural replenishment or percolation of surface waters into the groundwater aquifers, resulting in a corresponding increase in the amount of groundwater available for abstraction. India receives good amount of average annual rainfall about 114 cm but most of it's part waste through runoff. The imbalance between rainfall and recharge has caused serious shortage of water for drinking, agriculture and industrial purposes. The over exploitation of groundwater due to increasing population is an additional cause of water crisis that resulting in reduction in per capita availability of water in the country. Thus the planning for effective development of groundwater is essential through artificial recharge. Objective of the paper is to identification of artificial recharge zones by arresting runoff through suitable sites to restore groundwater conditions using statistical technique. The water table variation follows a pattern similar to rainfall variation with time delay. The rainfall and its relationship with recharge is a very important process in a shallow aquifer system. Understanding of this process is of critical importance to management of groundwater resource in any terrain. Groundwater system in a top weathered regolith in a balastic terrain forms shallow aquifer is often classified into shallow water table category. In the present study an effort has been made to understand the suitable recharge zone with relation to rainfall and water level by using statistical analysis. Daily time series data of rainfall and borehole water level data are cross correlated to investigate variations in groundwater level response time during the months of monsoon. This measurement facilitate to demarcate favorable areas for Artificial Recharge. KEYWORDS: Water level; Rainfall; Recharge; Statistical analysis; Cross correlation.

  13. Modern recharge to fossil aquifers: Geochemical, geophysical, and modeling constraints

    NASA Astrophysics Data System (ADS)

    Sultan, M.; Metwally, S.; Milewski, A.; Becker, D.; Ahmed, M.; Sauck, W.; Soliman, F.; Sturchio, N.; Yan, E.; Rashed, M.; Wagdy, A.; Becker, R.; Welton, B.

    2011-06-01

    The Nubian Sandstone (NSS) aquifer of northeast Africa is believed to have been recharged in previous wet climatic periods in the Quaternary Period. While this is largely true, we show using the Sinai Peninsula as our test site that the aquifer is locally receiving modern recharge under the current dry climatic conditions. The validity of the advocated model was tested using geophysical (conventional electrical resistivity [ER]) and isotopic (O, H) data, and estimates for modern recharge were obtained using continuous rainfall-runoff modeling over the period 1998-2007. Interpretations of ER profiles are consistent with the presence of unconfined NSS aquifers flooring recharge areas at the foothills of the crystalline basement in Sinai at Baraga (thickness: 20 to >188 m; resistivity: 16-130 Ω m) and Zalaga (thickness: 27 to >115 m; resistivity: 3-202 Ω m). The isotopic composition ( δD: -22.7 to -32.8‰; δ18O: -4.47 to -5.22‰) of groundwater samples from wells tapping the NSS aquifer underlying recharge areas is consistent with mixing between two endmembers: (1) fossil groundwater with isotopic compositions similar to those of the Western Desert NSS aquifer ( δD: -72 to -81‰; δ18O: -10.6 to -11.9‰), and (2) average modern meteoric precipitation ( δD: -9.84‰; δ18O: -3.48‰) in Sinai, with the latter endmember being the dominant component. A first-order estimate for the average annual modern recharge for the NSS aquifer was assessed at ˜13.0 × 10 6 m 3/yr using the SWAT (Soil Water Assessment Tool) model. Findings bear on the sustainable exploitation of the NSS aquifer, where the aquifer is being locally recharged, and on the exploitation of similar extensive aquifers that were largely recharged in previous wet climatic periods but are still receiving modest modern meteoric contributions.

  14. Soil Water Balance and Recharge Monitoring at the Hanford Site – FY 2010 Status Report

    SciTech Connect

    Fayer, Michael J.; Saunders, Danielle L.; Herrington, Ricky S.; Felmy, Diana

    2010-10-27

    This report summarizes the recharge data collected in FY 2010 at five locations on the Hanford Site in southeastern Washington State. Average monthly precipitation and temperature conditions in FY 2010 were near normal and did not present an opportunity for increased recharge. The recharge monitoring data confirmed those conditions, showing normal behavior in water content, matric head, and recharge rates. Also provided in this report is a strategy for recharge estimation for the next 5 years.

  15. Rechargeable Magnesium Batteries: Low-Cost Rechargeable Magnesium Batteries with High Energy Density

    SciTech Connect

    2010-10-01

    BEEST Project: Pellion Technologies is developing rechargeable magnesium batteries that would enable an EV to travel 3 times farther than it could using Li-ion batteries. Prototype magnesium batteries demonstrate excellent electrochemical behavior; delivering thousands of charge cycles with very little fade. Nevertheless, these prototypes have always stored too little energy to be commercially viable. Pellion Technologies is working to overcome this challenge by rapidly screening potential storage materials using proprietary, high-throughput computer models. To date, 12,000 materials have been identified and analyzed. The resulting best materials have been electrochemically tested, yielding several very promising candidates.

  16. Seasonal variation in natural recharge of coastal aquifers

    NASA Astrophysics Data System (ADS)

    Mollema, Pauline N.; Antonellini, Marco

    2013-06-01

    Many coastal zones around the world have irregular precipitation throughout the year. This results in discontinuous natural recharge of coastal aquifers, which affects the size of freshwater lenses present in sandy deposits. Temperature data for the period 1960-1990 from LocClim (local climate estimator) and those obtained from the Intergovernmental Panel on Climate Change (IPCC) SRES A1b scenario for 2070-2100, have been used to calculate the potential evapotranspiration with the Thornthwaite method. Potential recharge (difference between precipitation and potential evapotranspiration) was defined at 12 locations: Ameland (The Netherlands), Auckland and Wellington (New Zealand); Hong Kong (China); Ravenna (Italy), Mekong (Vietnam), Mumbai (India), New Jersey (USA), Nile Delta (Egypt), Kobe and Tokyo (Japan), and Singapore. The influence of variable/discontinuous recharge on the size of freshwater lenses was simulated with the SEAWAT model. The discrepancy between models with continuous and with discontinuous recharge is relatively small in areas where the total annual recharge is low (258-616 mm/year); but in places with Monsoon-dominated climate (e.g. Mumbai, with recharge up to 1,686 mm/year), the difference in freshwater-lens thickness between the discontinuous and the continuous model is larger (up to 5 m) and thus important to consider in numerical models that estimate freshwater availability.

  17. Estimating aquifer channel recharge using optical data interpretation.

    PubMed

    Walter, Gary R; Necsoiu, Marius; McGinnis, Ronald

    2012-01-01

    Recharge through intermittent and ephemeral stream channels is believed to be a primary aquifer recharge process in arid and semiarid environments. The intermittent nature of precipitation and flow events in these channels, and their often remote locations, makes direct flow and loss measurements difficult and expensive. Airborne and satellite optical images were interpreted to evaluate aquifer recharge due to stream losses on the Frio River in south-central Texas. Losses in the Frio River are believed to be a major contributor of recharge to the Edwards Aquifer. The results of this work indicate that interpretation of readily available remote sensing optical images can offer important insights into the spatial distribution of aquifer recharge from losing streams. In cases where upstream gauging data are available, simple visual analysis of the length of the flowing reach downstream from the gauging station can be used to estimate channel losses. In the case of the Frio River, the rate of channel loss estimated from the length of the flowing reach at low flows was about half of the loss rate calculated from in-stream gain-loss measurements. Analysis based on water-surface width and channel slope indicated that losses were mainly in a reach downstream of the mapped recharge zone. The analysis based on water-surface width, however, did not indicate that this method could yield accurate estimates of actual flow in pool and riffle streams, such as the Frio River and similar rivers draining the Edwards Plateau. PMID:21434908

  18. The Policy of "Pumping the Recharge" Is Out of Control

    NASA Astrophysics Data System (ADS)

    Balleau, W. Peter

    2013-01-01

    Hydrogeologists have spent several scientific generations in understanding the source of water to well fields and the effects of wells on the interrelated surface water system. The benchmark is by Theis [1940], who emphasized that some groundwater is initially mined during aquifer development and, after sufficient time, well discharge will be made up by diminution of both rejected recharge and natural discharge. Rejected recharge is water that would reside in the aquifer, except for a lack of space available. Theis advised that a perennial safe yield is equivalent to the amount of rejected recharge and natural discharge that is "feasible to utilize." His term "feasible" may have anticipated many current issues about aquifer sustainability. Papers published this year on the Ogallala aquifer in the central United States and on the global groundwater "footprint" [Scanlon et al., 2012; Gleeson et al., 2012] focus on recharge as an index of sustainability and have been featured in the popular press. However, I argue in this Forum that natural recharge rates alone cannot serve to address the core policy question regarding sustainable aquifer conditions in response to well field stresses. For the sake of users of hydrologic guidance, advisors on this topic may wish to reconsider the safe nature of "pumping the recharge."

  19. Thin-film Rechargeable Lithium Batteries

    DOE R&D Accomplishments Database

    Bates, J. B.; Gruzalski, G. R.; Dudney, N. J.; Luck, C. F.; Yu, X.

    1993-11-01

    Rechargeable thin films batteries with lithium metal anodes, an amorphous inorganic electrolyte, and cathodes of lithium intercalation compounds have been fabricated and characterized. The cathodes include TiS{sub 2}, the {omega} phase of V{sub 2}O{sub 5}, and the cubic spinel Li{sub x}Mn{sub 2}O{sub 4} with open circuit voltages at full charge of about 2.5 V, 3.7 V, and 4.2 V, respectively. The development of these robust cells, which can be cycled thousands of times, was possible because of the stability of the amorphous lithium electrolyte, lithium phosphorus oxynitride. This material has a typical composition of Li{sub 2.9}PO{sub 3.3}N{sub 0.46} and a conductivity at 25 C of 2 {mu}S/cm. Thin film cells have been cycled at 100% depth of discharge using current densities of 2 to 100 {mu}A/cm{sup 2}. The polarization resistance of the cells is due to the slow insertion rate of Li{sup +} ions into the cathode. Chemical diffusion coefficients for Li{sup +} ions in the three types of cathodes have been estimated from the analysis of ac impedance measurements.

  20. Rechargeable wireless EMG sensor for prosthetic control.

    PubMed

    Lichter, P A; Lange, E H; Riehle, T H; Anderson, S M; Hedin, D S

    2010-01-01

    Surface electrodes in modern myoelectric prosthetics are often embedded in the prosthesis socket and make contact with the skin. These electrodes detect and amplify muscle action potentials from voluntary contractions of the muscle in the residual limb and are used to control the prosthetic's movement and function. There are a number of performance-related deficiencies associated with external electrodes including the maintenance of sufficient electromyogram (EMG) signal amplitude, extraneous noise acquisition, and proper electrode interface maintenance that are expected to be improved or eliminated using the proposed implanted sensors. This research seeks to investigate the design components for replacing external electrodes with fully-implantable myoelectric sensors that include a wireless interface to the prosthetic limbs. This implanted technology will allow prosthetic limb manufacturers to provide products with increased performance, capability, and patient-comfort. The EMG signals from the intramuscular recording electrode are amplified and wirelessly transmitted to a receiver in the prosthetic limb. Power to the implant is maintained using a rechargeable battery and an inductive energy transfer link from the prosthetic. A full experimental system was developed to demonstrate that a wireless biopotential sensor can be designed that meets the requirements of size, power, and performance for implantation. PMID:21095801

  1. Recharge to the North Richland well field

    SciTech Connect

    Law, A.G.

    1989-07-01

    The investigation was based on a preliminary ground-water flow model of the 1100 Area. Because few local data were available for this effort, an existing regional ground-water flow model of the Hanford Site was applied, which is based on the Variable Thickness Transient (VTT) ground-water flow code (Kipp et al., 1976). A submodel of the Hanford Site model was developed based on the VTT code. An independent model consisting of a simple representation of the local conditions in the vicinity of the North Richland well field was also used in the investigation. This model, based on the MODFLOW code (McDonald and Harbaugh, 1984), was used in a series of transient simulations to examine dynamic aspects of the well field/recharge basin. Results from this simple model also provide an independent, qualitative check of results produced with the 1100 Area model based on the VTT code. This report summarizes the 1100 Area modeling investigation, including the approach used to generate results for the regional and 1100 Area VTT models, the approach used in the transient MODFLOW model, results from some initial steady-state and transient simulations with the submodel and the MODFLOW models, and resulting conclusions and recommendations. Because local data were lacking to develop and calibrate the models, the investigation described in this report can best be described as a ''sensitivity analysis'' of ground-water flow in the 1100 Area. 4 refs., 10 figs., 2 tabs.

  2. Wearable textile battery rechargeable by solar energy.

    PubMed

    Lee, Yong-Hee; Kim, Joo-Seong; Noh, Jonghyeon; Lee, Inhwa; Kim, Hyeong Jun; Choi, Sunghun; Seo, Jeongmin; Jeon, Seokwoo; Kim, Taek-Soo; Lee, Jung-Yong; Choi, Jang Wook

    2013-01-01

    Wearable electronics represent a significant paradigm shift in consumer electronics since they eliminate the necessity for separate carriage of devices. In particular, integration of flexible electronic devices with clothes, glasses, watches, and skin will bring new opportunities beyond what can be imagined by current inflexible counterparts. Although considerable progresses have been seen for wearable electronics, lithium rechargeable batteries, the power sources of the devices, do not keep pace with such progresses due to tenuous mechanical stabilities, causing them to remain as the limiting elements in the entire technology. Herein, we revisit the key components of the battery (current collector, binder, and separator) and replace them with the materials that support robust mechanical endurance of the battery. The final full-cells in the forms of clothes and watchstraps exhibited comparable electrochemical performance to those of conventional metal foil-based cells even under severe folding-unfolding motions simulating actual wearing conditions. Furthermore, the wearable textile battery was integrated with flexible and lightweight solar cells on the battery pouch to enable convenient solar-charging capabilities. PMID:24164580

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  4. Solid State Rechargeable Organic Batteries Based on Polymer Composites of Charge-transfer Materials

    NASA Astrophysics Data System (ADS)

    Gupta, R. K.; Srivastava, N.; Singh, R. A.

    2004-04-01

    Solid-state galvanic cells based on charge-transfer complexes have been extensively used. However, the low mechanical strengths of these materials have restricted their applications. To overcome this problem, the polymer composite of these materials have been prepared and used in fabrication of solid-state batteries. The pressed pellet of these materials has been used as cathode in contact with zinc as anode metal. The electrochemical characterization of these cells such as open-circuit voltages, short-circuit currents, their time and temperature dependence and rechargeability of these cells have been studied. The impedance analyses have been done to understand the nature of the electrode reaction.

  5. Evaluating the performance of water purification in a vegetated groundwater recharge basin maintained by short-term pulsed infiltration events.

    PubMed

    Mindl, Birgit; Hofer, Julia; Kellermann, Claudia; Stichler, Willibald; Teichmann, Günter; Psenner, Roland; Danielopol, Dan L; Neudorfer, Wolfgang; Griebler, Christian

    2015-01-01

    Infiltration of surface water constitutes an important pillar in artificial groundwater recharge. However, insufficient transformation of organic carbon and nutrients, as well as clogging of sediments often cause major problems. The attenuation efficiency of dissolved organic carbon (DOC), nutrients and pathogens versus the risk of bioclogging for intermittent recharge were studied in an infiltration basin covered with different kinds of macrovegetation. The quality and concentration of organic carbon, major nutrients, as well as bacterial biomass, activity and diversity in the surface water, the porewater, and the sediment matrix were monitored over one recharge period. Additionally, the numbers of viral particles and Escherichia coli were assessed. Our study showed a fast establishment of high microbial activity. DOC and nutrients have sustainably been reduced within 1.2 m of sediment passage. Numbers of E. coli, which were high in the topmost centimetres of sediment porewater, dropped below the detection limit. Reed cover was found to be advantageous over bushes and trees, since it supported higher microbial activities along with a good infiltration and purification performance. Short-term infiltration periods of several days followed by a break of similar time were found suitable for providing high recharge rates, and good water purification without the risk of bioclogging. PMID:26606084

  6. Feasibility of artificial recharge to the 800-foot sand of the Kirkwood Formation in the coastal plain near Atlantic City, New Jersey

    USGS Publications Warehouse

    May, J.E.

    1985-01-01

    Renewed development of the Atlantic City area since the mid-1970 's has increased the demand for water. Increased pumpage from the 800-foot sand of the Kirkwood Formation has reversed an antecedent water-level recovery in this aquifer, thus reducing water in storage and increasing the potential for saltwater intrusion. Practicable approaches to providing a dependable water supply while properly managing withdrawals from the 800-foot sand include development of surface- and ground-water supplies but artificial recharging the 800-foot sand is the principal alternative discussed. Investigation of its feasibility locally included a review of methods of artificial recharge and attendant operational problems, investigation of local hydrogeologic conditions, and collection and interpretation of water-quality data. System design and quality of injected water are important for successful artificial recharge. Mixtures of water from the 800-foot sand and from a representative local public-supply system may become supersaturated with oxygen. Significant temperature differences between two such waters would likely exacerbate that condition. Limited chemical analyses suggest that suspended solids concentration of water from local public supplies may at times be high enough to cause clogging of recharge-well screens. These problems are soluable by appropriate conditioning of recharge water. (USGS)

  7. Estimated Infiltration, Percolation, and Recharge Rates at the Rillito Creek Focused Recharge Investigation Site, Pima County, Arizona

    USGS Publications Warehouse

    Hoffmann, John P.; Blasch, Kyle W.; Pool, Don R.; Bailey, Matthew A.; Callegary, James B.

    2007-01-01

    A large fraction of ground water stored in the alluvial aquifers in the Southwest is recharged by water that percolates through ephemeral stream-channel deposits. The amount of water currently recharging many of these aquifers is insufficient to meet current and future demands. Improving the understanding of streambed infiltration and the subsequent redistribution of water within the unsaturated zone is fundamental to quantifying and forming an accurate description of streambed recharge. In addition, improved estimates of recharge from ephemeral-stream channels will reduce uncertainties in water-budget components used in current ground-water models. This chapter presents a summary of findings related to a focused recharge investigation along Rillito Creek in Tucson, Arizona. A variety of approaches used to estimate infiltration, percolation, and recharge fluxes are presented that provide a wide range of temporal- and spatial-scale measurements of recharge beneath Rillito Creek. The approaches discussed include analyses of (1) cores and cuttings for hydraulic and textural properties, (2) environmental tracers from the water extracted from the cores and cuttings, (3) seepage measurements made during sustained streamflow, (4) heat as a tracer and numerical simulations of the movement of heat through the streambed sediments, (5) water-content variations, (6) water-level responses to streamflow in piezometers within the stream channel, and (7) gravity changes in response to recharge events. Hydraulic properties of the materials underlying Rillito Creek were used to estimate long-term potential recharge rates. Seepage measurements and analyses of temperature and water content were used to estimate infiltration rates, and environmental tracers were used to estimate percolation rates through the thick unsaturated zone. The presence or lack of tritium in the water was used to determine whether or not water in the unsaturated zone infiltrated within the past 40 years. Analysis of water-level and temporal-gravity data were used to estimate recharge volumes. Data presented in this chapter were collected from 1999 though 2002. Precipitation and streamflow during this period were less than the long-term average; however, two periods of significant streamflow resulted in recharge?one in the summer of 1999 and the other in the fall/winter of 2000. Flux estimates of infiltration and recharge vary from less than 0.1 to 1.0 cubic meter per second per kilometer of streamflow. Recharge-flux estimates are larger than infiltration estimates. Larger recharge fluxes than infiltration fluxes are explained by the scale of measurements. Methods used to estimate recharge rates incorporate the largest volumetric and temporal scales and are likely to have fluxes from other nearby sources, such as unmeasured tributaries, whereas the methods used to estimate infiltration incorporate the smallest scales, reflecting infiltration rates at individual measurement sites.

  8. Design and simulation of lithium rechargeable batteries

    SciTech Connect

    Doyle, C.M.

    1995-08-01

    Lithium -based rechargeable batteries that utilize insertion electrodes are being considered for electric-vehicle applications because of their high energy density and inherent reversibility. General mathematical models are developed that apply to a wide range of lithium-based systems, including the recently commercialized lithium-ion cell. The modeling approach is macroscopic, using porous electrode theory to treat the composite insertion electrodes and concentrated solution theory to describe the transport processes in the solution phase. The insertion process itself is treated with a charge-transfer process at the surface obeying Butler-Volmer kinetics, followed by diffusion of the lithium ion into the host structure. These models are used to explore the phenomena that occur inside of lithium cells under conditions of discharge, charge, and during periods of relaxation. Also, in order to understand the phenomena that limit the high-rate discharge of these systems, we focus on the modeling of a particular system with well-characterized material properties and system parameters. The system chosen is a lithium-ion cell produced by Bellcore in Red Bank, NJ, consisting of a lithium-carbon negative electrode, a plasticized polymer electrolyte, and a lithium-manganese-oxide spinel positive electrode. This battery is being marketed for consumer electronic applications. The system is characterized experimentally in terms of its transport and thermodynamic properties, followed by detailed comparisons of simulation results with experimental discharge curves. Next, the optimization of this system for particular applications is explored based on Ragone plots of the specific energy versus average specific power provided by various designs.

  9. Isotopic assessment of the recharge of a coastal aquifer in N. Albania

    NASA Astrophysics Data System (ADS)

    Jacks, Gunnar; Kumanova, Xhume; Marku, Sonila

    2013-04-01

    The River Mati coastal plain aquifers serve as a groundwater source for about 250 000 people. A major concern is the rate of recharge from an alluvial fan at the entry of River Mati into the coastal plain. The investigation revealed brackish groundwater close to the Adriatic coast. However, the groundwater was artesian indicating the sea water intrusion is not currently a threat. As per ^18O analysis this water was not a mix of old sea water but had the signature of the river water. The salinity is likely to be derived by diffusion from intercalated clay layers. 14C dating of the water showed ages of the most brackish water up to 7 000 years. Upstream there are a large number of active and abandoned copper mines and about 10 M ton of waste rock from these mines. The ^34S in the river water was close to the value for sulphides in this waste rock. Also the groundwater showed values close to that of the river. Only the brackish groundwater close to the sea shore had a sea water signature, probably derived from sulphate diffusion from the above mentioned clay layers. Thus currently the groundwater extracted in a large well-field for the Durres town is more or less completely fed by recharge from the river. Large scale sand and gravel extraction in the alluvial cone is a threat to this recharge, lowering the head for flow and also presenting a risk for pollution by oil and fuel from the vehicles used for the sand and gravel extraction. It is recommended that a number of the artesian wells close to the Adriatic coast are monitored regarding the head above ground level.

  10. Fuel cells feasibility

    NASA Technical Reports Server (NTRS)

    Schonfeld, D.; Charng, T.

    1981-01-01

    The technical and economic status of fuel cells is assessed with emphasis on their potential benefits to the Deep Space Network. The fuel cell, what it is, how it operates, and what its outputs are, is reviewed. Major technical problems of the fuel cell and its components are highlighted. Due to these problems and economic considerations it is concluded that fuel cells will not become commercially viable until the early 1990s.

  11. A methodology for making initial estimates of groundwater recharge from groundwater vulnerability mapping

    NASA Astrophysics Data System (ADS)

    Misstear, B. D. R.; Brown, L.; Daly, D.

    2009-03-01

    Recharge to an aquifer can be estimated by first calculating the effective rainfall using a soil moisture budgeting technique, and then by applying a recharge coefficient to indicate the proportion of this effective rainfall that contributes to groundwater recharge. In the Republic of Ireland, the recharge coefficient is determined mainly by the permeability and thickness of the superficial deposits (subsoils) that overlie the country’s aquifers. The properties of these subsoils also influence groundwater vulnerability, and a methodology has been developed for determining the recharge coefficient using the groundwater vulnerability classification. The results of four case studies have been used to develop a quantified link between subsoil permeability, aquifer vulnerability, recharge and runoff. Recharge and runoff coefficients are each classed into three groupings: high, intermediate and low. A high recharge coefficient equates to a low runoff coefficient, and vice versa. A GIS-based tool enables preliminary estimates of recharge to be made using these recharge coefficient groupings. Potential recharge is calculated as the product of effective rainfall and recharge coefficient. The actual recharge is then calculated taking account of the ability of the aquifer to accept the available recharge. The methodology could be applied to other temperate climate zones where the main aquifers have a substantial covering of superficial deposits.

  12. A fuel cell energy storage system for Space Station extravehicular activity

    NASA Technical Reports Server (NTRS)

    Rosso, Matthew J., Jr.; Adlhart, Otto J.; Marmolejo, Jose A.

    1988-01-01

    The development of a fuel cell energy storage system for the Space Station Extravehicular Mobility Unit (EMU) is discussed. The ion-exchange membrane fuel cell uses hydrogen stored as a metal hydride. Several features of the hydrogen-oxygen fuel cell are examined, including its construction, hydrogen storage, hydride recharge, water heat, water removal, and operational parameters.

  13. Groundwater recharge from Long Lake, Indiana Dunes National Lakeshore

    SciTech Connect

    Isiorho, S.A.; Beeching, F.M. . Geosciences Dept.); Whitman, R.L.; Stewart, P.M. . Indiana Dunes National Lakeshore); Gentleman, M.A.

    1992-01-01

    Long Lake, located between Lake Michigan and the Dune-complexes of Indiana Dunes, was formed during Pleistocene and Holocene epochs. The lake is currently being studied to understand the detailed hydrology. One of the objective of the study is to understand the hydrologic relationship between the lake and a water treatment holding pond to the northeast. Understanding the water movement between the two bodies of water, if any, would be very important in the management and protection of nature preserves in the area. Seepage measurement and minipiezometric tests indicate groundwater recharge from Long Lake. The groundwater recharge rate is approximately 1.40 to 22.28 x 10[sup [minus]4] m/day. An estimate of the amount of recharge of 7.0 x 10[sup 6] m[sup 3]/y may be significant in terms of groundwater recharge of the upper aquifer system of the Dunes area. The water chemistry of the two bodies of water appears to be similar, however, the pH of the holding pond is slightly alkaline (8.5) while that of Long Lake is less alkaline (7.7). There appears to be no direct contact between the two bodies of water (separated by approximately six meters of clay rich sediment). The geology of the area indicates a surficial aquifer underlying Long Lake. The lake should be regarded as a recharge area and should be protected from pollutants as the degradation of the lake would contaminate the underlying aquifer.

  14. Factors affecting areas contributing recharge to wells in shallow aquifers

    USGS Publications Warehouse

    Reilly, Thomas E.; Pollock, David W.

    1993-01-01

    The source of water to wells is ultimately the location where the water flowing to a well enters the boundary surface of the ground-water system. In ground-water systems that receive most of their water from areal recharge, the location of the water entering the ground-water system is at the water table. The area contributing recharge to a discharging well is the surface area that defines the location of the water entering the ground-water system at the water table that flows to the well and is eventually discharged from the well. The calculation of areas contributing recharge to wells is complex because flow paths in ground-water systems change in response to development, and the aquifer material in ground-water systems is heterogeneous and is hidden from direct observation . Hypothetical experiments were undertaken to show the complexities in the delineation of areas contributing recharge to wells. Four different 'cases' are examined to demonstrate the effect of different conceptualized aquifer frameworks on deterministically calculated areas contributing recharge. The main conclusion drawn from the experiments is that, in order to understand the cause and effect relations that affect the quality of water derived from wells, the importance and nature of the variability in the ground-waterflow system must be considered and accounted for in any efforts to 'protect' the water supply.

  15. Geochemical Triggers of Arsenic Mobilization during Managed Aquifer Recharge.

    PubMed

    Fakhreddine, Sarah; Dittmar, Jessica; Phipps, Don; Dadakis, Jason; Fendorf, Scott

    2015-07-01

    Mobilization of arsenic and other trace metal contaminants during managed aquifer recharge (MAR) poses a challenge to maintaining local groundwater quality and to ensuring the viability of aquifer storage and recovery techniques. Arsenic release from sediments into solution has occurred during purified recycled water recharge of shallow aquifers within Orange County, CA. Accordingly, we examine the geochemical processes controlling As desorption and mobilization from shallow, aerated sediments underlying MAR infiltration basins. Further, we conducted a series of batch and column experiments to evaluate recharge water chemistries that minimize the propensity of As desorption from the aquifer sediments. Within the shallow Orange County Groundwater Basin sediments, the divalent cations Ca(2+) and Mg(2+) are critical for limiting arsenic desorption; they promote As (as arsenate) adsorption to the phyllosilicate clay minerals of the aquifer. While native groundwater contains adequate concentrations of dissolved Ca(2+) and Mg(2+), these cations are not present at sufficient concentrations during recharge of highly purified recycled water. Subsequently, the absence of dissolved Ca(2+) and Mg(2+) displaces As from the sediments into solution. Increasing the dosages of common water treatment amendments including quicklime (Ca(OH)2) and dolomitic lime (CaO·MgO) provides recharge water with higher concentrations of Ca(2+) and Mg(2+) ions and subsequently decreases the release of As during infiltration. PMID:26057865

  16. Fate of human viruses in groundwater recharge systems

    SciTech Connect

    Vaughn, J.M.; Landry, E.F.

    1980-03-01

    The overall objective of this research program was to determine the ability of a well-managed tertiary effluent-recharge system to return virologically acceptable water to the groundwater aquifer. The study assessed the quality of waters renovated by indigenous recharge operations and investigated a number of virus-soil interrelationships. The elucidation of the interactions led to the establishment of basin operating criteria for optimizing virus removal. Raw influents, chlorinated tertiary effluents, and renovated wastewater from the aquifer directly beneath a uniquely designed recharge test basin were assayed on a weekly basis for the presence of human enteroviruses and coliform bacteria. High concentrations of viruses were routinely isolated from influents but were isolated only on four occasions from tertiary-treated sewage effluents. In spite of the high quality effluent being recharged, viruses were isolated from the groundwater observation well, indicating their ability to penetrate the unsaturated zone. Results of poliovirus seeding experiments carried out in the test basin clearly indicated the need to operate recharge basins at low (e.g. 1 cm/h) infiltration rates in areas having soil types similar to those found at the study site. The method selected for reducing the test basin infiltration rate involved clogging the basin surface with settled organic material from highly turbid effluent. Alternative methods for slowing infiltration rates are discussed in the text.

  17. Artificial-Recharge Experiments and Operations on the Southern High Plains of Texas and New Mexico

    USGS Publications Warehouse

    Brown, Richmond F.; Signor, Donald C.

    1973-01-01

    Experiments using highly turbid water from playa lakes for injection into the Ogallala Formation have resulted in greatly decreased yield of the recharge wells, Recharge of ground or surface water of good quality has indicated, however, that injection through wells is an effective method of recharging the aquifer. Water that is slightly turbid can be successfully injected for a period of time, but generally results in constantly declining yields and capacity for recharge. Redevelopment through pumping and surging significantly prolongs the life of recharge wells under some conditions. Surface spreading is little practiced on the High Plains, but locally may be a feasible means of artificial recharge.

  18. Investigation of groundwater recharge in arid environments through continuous monitoring of water fluxes within the unsaturated zone

    NASA Astrophysics Data System (ADS)

    Kallioras, A.; Reshid, M.; Dietrich, P.; Rausch, R.; Al-Saud, M.; Schuth, C.

    2012-04-01

    For groundwater resources management in arid environments the rate of aquifer replenishment due to groundwater recharge is one of the most important factors and unfortunately also one of the most difficult to derive with sufficient accuracy. In general, the potential evaporation by far exceeds the precipitation limiting groundwater recharge. Unsaturated zone processes play a key role in groundwater recharge as the thickness of the unsaturated zone in arid areas may reach several thenth of meters, compared to millimeters or centimeters of assumed groundwater recharge per year. This indicates the complexity of the problem. Overcoming the field capacity along the infiltration path to initiate downward movement on such a long distance to the groundwater table would require the recharge of tenths or even hundreds of years. Also, precipitation is highly variable in space, time, and intensity and may be followed by hot and dry conditions leading to an alternation of downward and upward movement of water. For this study, field sites in the Kingdom of Saudi Arabia (located app. 200km SW of Riyadh) were selected that represent typical settings for potential groundwater recharge in arid regions, i.e. sand dune areas and wadi beds. In the field campaign vibro-coring techniques applying direct-push technologies (Geoprobe 7720DT) were used to retrieve undisturbed soil sampling down to depths of about 15 m in the unsaturated zone. The drilled boreholes were consequently used for the installation of specially designed flat cable TDR sensors that provide continuous monitoring of the soil moisture content in high vertical resolution. In addition, temperature sensors were installed to monitor temperature fluctuations in the unsaturated zone. We present data on the analyses of soil samples as well as on the measured water content evolution over time as determined by the TDR flat band cables. Results show, that significant changes in water content occurred within the observation time indicating the potential for groundwater recharge even under the arid conditions encountered at the field sites. Acknowledgements The authors would like to acknowledge the cooperation between Helmholtz-Centre for Environmental Research-UFZ (Leipzig, Germany); Technical University of Darmstadt (Germany); GIZ-IS/Dornier Consulting (Riyadh Office, Kingdom of Saudi Arabia) and the Ministry of Water and Electricity (Kingdom of Saudi Arabia); within the framework of the German Federal Ministry of Education and Research (BMBF) funded research program IWAS (http://www.iwas-sachsen.ufz.de/).

  19. Estimation of recharge through selected drainage wells and potential effects from well closure, Orange County, Florida

    USGS Publications Warehouse

    Bradner, L.A.

    1996-01-01

    Drainage wells have been used in Orange County, Florida, and surrounding areas to alleviate flooding and to control lake levels since 1904. Over 400 drainage wells have been drilled in the county, but many are now redundant because of surface drainage systems that have been installed within the last two or three decades. Most of the drainage wells emplace water into the Upper Floridan aquifer, a zone of high transmissivity within the Floridan aquifer system. In 1992, the Orange County Stormwater Management Department identified 23 wells that were considered noncritical or redundant for current drainage control. These wells were targeted for closure to eliminate maintenance and possible contamination problems. A 3-year study (1992 through 1994) encompassed several drainage basins in the county. Inflow to 18 of the 23 drainage wells on the noncritical list and the effects of closure of these noncritical wells on the potentiometric surface of the Upper Floridan aquifer were estimated. Three sites were chosen for intensive study and were used for further extrapolation to other noncritical sites. The total average annual recharge rate through the 18 selected wells was estimated to be 9 cubic feet per second, or about 6 million gallons per day. The highest rate of long-term recharge, 4.6 cubic feet per second, was to well H-35. Several wells on the noncritical list were already plugged or had blocked intakes. Yields, or the sum of surface-water outflows and drainage-well recharge, from the drainage basins ranged from 20 to 33 inches per year. In some of the basins, all the yield from the basin was recharge through a drainage well. In other basins, most of the yield was surface outflow through canals rather than to drainage wells. The removal of the recharge from closure of the wells was simulated by superposition in a three-dimensional ground-water flow model. As a second step in the model, water was also applied to two sites in western Orange County that could receive redirected surface water. One of the sites is CONSERV II, a distribution system used to apply reclaimed water to the surficial aquifer system through rapid infiltration basins and grove irrigation. The second site, Lake Sherwood, has an extremely high downward recharge rate estimated to be at least 54 inches per year. The results from the simulations showed a decline of 1 foot or less in the potentiometric surface of the Upper Floridan aquifer with removal of the recharge and a mound of about 1 foot in the vicinity of the two sites in western Orange County. The Lake Sherwood site seems to reduce the declines caused by closure of the wells to a greater degree than the CONSERV II site, partly because the Lake Sherwood site is closer to the drainage-well basins.

  20. Fuel flexible fuel injector

    SciTech Connect

    Tuthill, Richard S; Davis, Dustin W; Dai, Zhongtao

    2015-02-03

    A disclosed fuel injector provides mixing of fuel with airflow by surrounding a swirled fuel flow with first and second swirled airflows that ensures mixing prior to or upon entering the combustion chamber. Fuel tubes produce a central fuel flow along with a central airflow through a plurality of openings to generate the high velocity fuel/air mixture along the axis of the fuel injector in addition to the swirled fuel/air mixture.

  1. Polymeric metallic electrodes for rechargeable battery applications

    NASA Technical Reports Server (NTRS)

    Somoano, R.

    1982-01-01

    A review is presented on the status of plastic metal electrodes, emphasizing the use of polyacetylene as a prototype polymeric material. The electrochemical characteristics of polyacetylene are examined; and the potential use of this material, as well as other types of plastic metal electrodes, in batteries is evaluated. Several problem areas which must be solved before polyacetylene can be widely used in battery applications are discussed, including the problem of electrolyte stability, the problem that the depth of discharge and the energy density is limited by the metal-semiconductor transition, and also the poor electrochemical performance of impure material.

  2. Activated Li2S as a High-Performance Cathode for Rechargeable Lithium-Sulfur Batteries.

    PubMed

    Zu, Chenxi; Klein, Michael; Manthiram, Arumugam

    2014-11-20

    Lithium-sulfur (Li-S) batteries with a high theoretical energy density of ∼2500 Wh kg(-1) are considered as one promising rechargeable battery chemistry for next-generation energy storage. However, lithium-metal anode degradation remains a persistent problem causing safety concerns for Li-S batteries, hindering their practical utility. One possible strategy to circumvent the aforementioned problems is to use alternative, high-capacity, lithium-free anodes (e.g., Si, Sn, carbon) and a Li2S cathode. However, a large potential barrier was identified on the initial charge of insulating bulk Li2S particles, limiting the cell performance. In this work, the bulk Li2S particles were effectively activated with an electrolyte containing P2S5, resulting in a lowered initial charging voltage plateau. This permits the direct use of commercially available bulk Li2S particles as a high-capacity cathode for room-temperature, rechargeable Li-S batteries, significantly lowering the manufacturing cost of Li-S cells. PMID:26276482

  3. Sulfone-based electrolytes for aluminium rechargeable batteries.

    PubMed

    Nakayama, Yuri; Senda, Yui; Kawasaki, Hideki; Koshitani, Naoki; Hosoi, Shizuka; Kudo, Yoshihiro; Morioka, Hiroyuki; Nagamine, Masayuki

    2015-02-28

    Electrolyte is a key material for success in the research and development of next-generation rechargeable batteries. Aluminium rechargeable batteries that use aluminium (Al) metals as anode materials are attractive candidates for next-generation batteries, though they have not been developed yet due to the lack of practically useful electrolytes. Here we present, for the first time, non-corrosive reversible Al electrolytes working at room temperature. The electrolytes are composed of aluminium chlorides, dialkylsulfones, and dilutants, which are realized by the identification of electrochemically active Al species, the study of sulfone dependences, the effects of aluminium chloride concentrations, dilutions and their optimizations. The characteristic feature of these materials is the lower chloride concentrations in the solutions than those in the conventional Al electrolytes, which allows us to use the Al metal anodes without corrosions. We anticipate that the sulfone-based electrolytes will open the doors for the research and development of Al rechargeable batteries. PMID:25627398

  4. Heat transport in the vicinity of an artificial recharge site

    NASA Astrophysics Data System (ADS)

    Vandenbohede, Alexander; van Houtte, Emmanuel; Lebbe, Luc

    2010-05-01

    Since July 2002, the Intermunicipal Water Company of the Veurne region (IWVA) artificially recharges fresh water in the dunes of the western Belgian coastal plain by means of two recharge ponds. This recharge water is produced from secondary treated waste water effluent by the combination of ultra filtration and reverse osmosis. Extraction wells (112) are located north and south of the ponds. The artificial recharge project loops the water cycle: extracted water goes to the users and their waste water is purified and re-used. Therefore, it is an example of sustainable water management in coastal aquifers. Groundwater flow of this recharge site has been examined in the past by the use of a tracer test, hydrochemistry (environmental isotopes, conservative tracers) and groundwater flow modelling. Temperature, however, forms a relatively easy measurement which can add to or confirm the knowledge of the groundwater flow. Temperature time series (temperature as function of time) were measured at different levels in a number of wells located between the recharge ponds and the extraction wells, and in one well south of the recharge and extraction area. Secondly, temperature logs (temperature as function of depth) were measured in these wells at different times over the course of 2 years. Finally, the temperature of the recharged and extracted water is constantly monitored by the water company. The temperature of the recharge water shows a yearly fluctuation, ranging from 25 °C during summer to slightly above 0 °C during the winter. The temperature of the extracted water (combination of water extracted in all the wells) ranges between 17 °C during summer and 10 °C during winter. Minima and maxima in the extracted water are observed between 76 and 110 days (mean of 90 days and standard deviation of 13.5 days) later in the extracted water with respect to the recharged water. Measurements show that the difference in time when maxima and minima are observed in an observation well with reference to the ponds increases with depth (for instance from 28 days 4.1 m below surface to 154 days 10 m below surface for an observation well at 10 m from the ponds). This confirms previous flow modelling which showed that groundwater flows relatively rapidly laterally from the recharge ponds towards the extraction wells. Additionally, part of the recharge water flows in a deeper flow cycle towards the extraction wells. Residence times in this deeper flow cycle are evidently larger than in the direct lateral flow cycle from the ponds towards the wells. This explains the increase with depth. The 154 days (with respect to a mean time of 90 days) points to the fact that the extracted water contains a large spectrum of residence times with mean of 90 days for the heat transport, as was also derived by the flow modelling previously

  5. 76 FR 70531 - Fifth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems-Small...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-14

    ... Federal Aviation Administration Fifth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery.... Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 225, Rechargeable Lithium... public of a meeting of RTCA Special Committee 225, Rechargeable Lithium Battery and Battery...

  6. Evaluation of artificial groundwater recharge effects with MIKE-SHE: a case study.

    NASA Astrophysics Data System (ADS)

    Leal, M.; Martínez-García, I.; Carreño, F.; de Bustamante, I.; Lillo, J.

    2012-04-01

    In many areas where the technical and financial resources are limited, the treatment and disposal of wastewater comprise a problem. With increasing frequency, the wastewater reuse is considered as another alternative for water management alternative. In this way, the wastewater is converted into an added value resource. Treated wastewater infiltration into the soil could be a viable tertiary treatment, especially for small communities where the availability of land is not a problem and the wastewater has not industrial waste contribution and is highly biodegradable. The Experimental Plant of Carrión de los Céspedes (Seville, Spain) develops non-conventional wastewater treatments for small villages. Currently, a project regarding wastewater reutilization for aquifer recharge through a horizontal permeable reactive barrier and a subsequent soil infiltration is being carried out. One of the aspects to be evaluated within this context is the impact on aquifer. Consequently, the main goal of the present study is to assess the effects on the water flow derived from the future recharge activities by using the MIKE-SHE hydrological code. The unsaturated and saturated zones have been integrated in the model, which requires geological, land use, topography, piezometric head, soil and climate data to build up the model. The obtained results from the model show that with the annual recharge volume contributed by the experimental plant (3 m3 or 0.19 L/s) there is no effect in the groundwater flow. A volume of 400 m3/year (25 L/s) would be required to yield a variation in the piezometric head and therefore, in the groundwater flow i.e. a volume about 100 times larger than the estimated is necessary. To calibrate the model, simulated piezometric head values have been compared to the measured field data at a number of locations. In the calibration, the percent error had to be lower than 15 % at each location. Future works concerning groundwater quality and reactive transport modelling should be undertaken in order to get a more accurate impact evaluation of the recharge activities.

  7. Using stable isotopes of water to re-evaluate the recharge/discharge functions of North American bogs and fens

    NASA Astrophysics Data System (ADS)

    Levy, Zeno; Siegel, Donald; Glaser, Paul; Dasgupta, Soumitri

    2014-05-01

    In North American mires hydrologists commonly find raised bog crests and low-lying fen water tracks to be focal points for groundwater recharge and discharge, respectively. To further test these observations we synoptically surveyed vertical profiles of peat pore water δ18O/δ2H and major mineral solutes from a range of bog and fen landforms across the Glacial Lake Agassiz Peatlands (GLAP) of northern Minnesota. We also sampled a detailed transect through a 150 km2 bog-fen complex in the Red Lake II peatland watershed of the GLAP. The molar ratios of Ca/Mg in the pore water beneath the Red Lake II bog crest are depleted in Mg with respect to the atmospheric average of 3.6, indicative of preferential flushing of Mg from the peat by meteoric recharge. Higher solute concentrations in the middle of the peat profile at an adjacent fen show focused groundwater discharge with Ca/Mg ratios of ~1.4, similar to that of water from local wells tapping underlying glacial till. However, contrary to expectations, we find evidence that modern recharge has penetrated throughout the peat column beneath both bog and fen landforms throughout the GLAP. Landform surface features control the isotopic recharge value. These landform-specific isotope signatures propagate through vertical pore water profiles. Pore waters deeper than 0.5 m partition into discrete ranges of δ18O according to three a priori landform classifications: 1) -11.9 ± 0.4 o for bog crests, 2) -10.6 ± 0.1 o for Sphagnum lawns, and 3) -8.8 ± 1.0 o for fen water tracks. The fen water tracks have standing water at their surface that is seasonally enriched by isotope fractionating evaporation and therefore fingerprints recharge to depths ≥3 m. Incongruities between isotope and solute mixing trends may be related to the dual porosity nature of peat and matrix diffusion, which could supply solutes to active pore spaces following flushing by meteoric recharge. This buffering of base solutes in the deep peat may influence methanogenic bacteria that are sensitive to pH. Our results support the hypothesis that the downward transport of labile carbon substrates from the surface of northern peat basins fuels methane production in deeper peat strata.

  8. Hydrogeological evaluation of an over-exploited aquifer in Dhaka, Bangladesh towards the implementation of groundwater artificial recharge

    NASA Astrophysics Data System (ADS)

    Azizur Rahman, M.; Rusteberg, Bernd; Sauter, Martin

    2010-05-01

    The population of Dhaka City is presently about 12 million and according to present trends in population growth, that number will most likely increase to 17.2 million by the year 2025. A serious water crisis is expected due to the extremely limited quality and quantity of water resources in the region. Previous studies have shown that the current trend in groundwater resource development is non-sustainable due to over-exploitation of the regional aquifer system, resulting in rapidly decreasing groundwater levels of about 2 to 3 meters per year. Today, annual groundwater extraction clearly exceeds natural groundwater recharge. New water management strategies are needed to guarantee future generations of Dhaka City a secured and sustained water supply as well as sustainable development of the city. The implementation of groundwater artificial recharge (AR) is one potential measure. As the first step towards a new water management strategy for Dhaka City, the authors report on the hydrogeological conditions of the greater Dhaka region and from this are able to present the location of potential recharge sites and identify appropriate recharge technologies for AR implementation. The aquifers of greater Dhaka can be grouped in three major categories: Holocene Deposit, Pleistocene Deposit and Plio-Pleistocene Deposit. The aquifers are generally thick and multilayered with relatively high transmissivity and storage coefficients. AR is considered feasible due to the fact these aquifers are alluvium deposit aquifers which characteristically have moderate to high hydraulic conductivity. Low costs for recovery of recharged water and large recharge volume capacity are generally associated with aquifers of unconsolidated sediments. Spatial analysis of the region has shown that Karaniganj, Kotoali, Savar, Dhamrai, Singair upazila, which are situated in greater Dhaka region and close to Dhaka City, could serve as recharge sites to the subsurface by pond infiltration technique. A study involving the use of a 3-D mathematical model shows that the abstraction or recharge in the area within and around Dhaka City does not affect the groundwater level below the city. Therefore, in order to improve the groundwater level, artificial groundwater recharge directly at the city area would be mostly appropriate. As the thickness of the surface impermeable layer varies from 5 m to 45 m, the combination of infiltration and injection technology would be a proper choice. Detailed studies are required using the most appropriate state of the art spatial analysis to support the final selection and ranking of suitable locations for the AR facilities, according to flood risk, urbanization, underground characteristics, water sources, AR technology and later use of the recovered water. Groundwater quality data reveal that the upper aquifer below Dhaka City contains relatively high concentrations of dissolved ions, quite variable in space. The ground water is predominantly of Ca-Mg-HCO3 type. Cation exchange and oxidation may enhance the biogeochemical processes in the aquifer under the existing prevailing conditions. Many reports conclude that that the groundwater chemistry of the upper aquifer has been influenced by various anthropogenic processes, showing wide variations of groundwater quality depending on the area, which would complicate the implementation of AR projects. The preliminary evaluation of the potential for AR implementation, considering environmental and social impacts, as well as the available water sources for infiltration and injection (conventional or non-conventional), AR may be considered a viable response measure with regards to the problems Dhaka City is facing. Without the implementation of groundwater artificial recharge or similar measures, groundwater availability and groundwater quality will further decrease and serious water crisis are to be expected. Measures to avoid groundwater contamination must also be taken to complement the benefits provided by AR implementation.

  9. Thin Rechargeable Batteries for CMOS SRAM Memory Protection

    NASA Technical Reports Server (NTRS)

    Crouse, Dennis N.

    1993-01-01

    New rechargeable battery technology is described and compared with classical primary battery back-up of SRAM PC cards. Thin solid polymer electrolyte cells with the thickness of TSOP memory components (1 mm nominal, 1.1 mm max) and capacities of 14 mAh/sq cm can replace coin cells. The SRAM PC cards with permanently installed rechargeable cells and optional electrochromic low battery voltage indicators will free the periodic PC card user from having to 'feed' their PC cards with coin cells and will allow a quick visual check of stored cards for their battery voltage status.

  10. Focused Ground-Water Recharge in the Amargosa Desert Basin

    USGS Publications Warehouse

    Stonestrom, David A.; Prudic, David E.; Walvoord, Michelle A.; Abraham, Jared D.; Stewart-Deaker, Amy E.; Glancy, Patrick A.; Constantz, Jim; Laczniak, Randell J.; Andraski, Brian J.

    2007-01-01

    The Amargosa River is an approximately 300-kilometer long regional drainage connecting the northern highlands on the Nevada Test Site in Nye County, Nev., to the floor of Death Valley in Inyo County, Calif. Streamflow analysis indicates that the Amargosa Desert portion of the river is dry more than 98 percent of the time. Infiltration losses during ephemeral flows of the Amargosa River and Fortymile Wash provide the main sources of ground-water recharge on the desert-basin floor. The primary use of ground water is for irrigated agriculture. The current study examined ground-water recharge from ephemeral flows in the Amargosa River by using streamflow data and environmental tracers. The USGS streamflow-gaging station at Beatty, Nev., provided high-frequency data on base flow and storm runoff entering the basin during water years 1998?2001. Discharge into the basin during the four-year period totaled 3.03 million cubic meters, three quarters of which was base flow. Streambed temperature anomalies indicated the distribution of ephemeral flows and infiltration losses within the basin. Major storms that produced regional flow during the four-year period occurred in February 1998, during a strong El Ni?o that more than doubled annual precipitation, and in July 1999. The study also quantified recharge beneath undisturbed native vegetation and irrigation return flow beneath irrigated fields. Vertical profiles of water potential and environmental tracers in the unsaturated zone provided estimates of recharge beneath the river channel (0.04?0.09 meter per year) and irrigated fields (0.1?0.5 meter per year). Chloride mass-balance estimates indicate that 12?15 percent of channel infiltration becomes ground-water recharge, together with 9?22 percent of infiltrated irrigation. Profiles of potential and chloride beneath the dominant desert-shrub vegetation suggest that ground-water recharge has been negligible throughout most of the basin since at least the early Holocene. Surface-based electrical-resistivity imaging provided areal extension of borehole information from sampled profiles. These images indicate narrowly focused recharge beneath the Amargosa River channel, flanked by large tracts of recharge-free basin floor.

  11. Modelling of recharge and pollutant fluxes to urban groundwaters.

    PubMed

    Thomas, Abraham; Tellam, John

    2006-05-01

    Urban groundwater resources are of considerable importance to the long-term viability of many cities world-wide, yet prediction of the quantity and quality of recharge is only rarely attempted at anything other than a very basic level. This paper describes the development of UGIf, a simple model written within a GIS, designed to provide estimates of spatially distributed recharge and recharge water quality in unconfined but covered aquifers. The following processes (with their calculation method indicated) are included: runoff and interception (curve number method); evapotranspiration (Penman-Grindley); interflow (empirical index approach); volatilization (Henry's law); sorption (distribution coefficient); and degradation (first order decay). The input data required are: meteorological data, landuse/cover map with event mean concentration attributes, geological maps with hydraulic and geochemical attributes, and topographic and water table elevation data in grid form. Standard outputs include distributions of: surface runoff, infiltration, potential recharge, ground level slope, interflow, actual recharge, pollutant fluxes in surface runoff, travel times of each pollutant through the unsaturated zone, and the pollutant fluxes and concentrations at the water table. The process of validation has commenced with a study of the Triassic Sandstone aquifer underlying Birmingham, UK. UGIf predicts a similar average recharge rate for the aquifer as previous groundwater flow modelling studies, but with significantly more spatial detail: in particular the results indicate that recharge through paved areas may be more important than previously thought. The results also highlight the need for more knowledge/data on the following: runoff estimation; interflow (including the effects of lateral flow and channelling on flow times and therefore chemistry); evapotranspiration in paved areas; the nature of unsaturated zone flow below paved areas; and the role of the pipe network. Although considerably more verification is needed, UGIf shows promise for use: in providing input for regional groundwater solute transport models; in identifying gaps in knowledge and data; in determining which processes are the most important influences on urban groundwater quantity and quality; in evaluating existing recharge models; in planning, for example in investigation of the effects of landuse or climate change; and in assessing groundwater vulnerability. PMID:16325236

  12. Construction of the Plant RT-2 as a way for solving the problem of VVER-1000 spent fuel management in Russia

    SciTech Connect

    Lazarev, L.N.; Lyubtsev, R.I.; Egorov, N.N.; Lebedev, V.A.; Revenko, Y.A.; Fedosov, Y.G.; Dubrovskii, V.M.

    1993-12-31

    Nuclear power in the Russian Federation in the future will be based on the VVER-1000 and it`s modifications. To manage the spent fuels from this plant, the Plant RT-2 was designed to process the spent fuel. Plant construction was started in 1984 and stopped in 1989 due to economic difficulties. The necessity of the continuation of the plant is discussed.

  13. VIRUS REMOVAL DURING GROUNDWATER RECHARGE: EFFECTS OF INFILTRATION RATE ON ADSORPTION OF POLIOVIRUS TO SOIL

    EPA Science Inventory

    Studies were conducted to determine the influence of infiltration rate on poliovirus removal during groundwater recharge with tertiary-treated wastewater effluents. Experiments were conducted at a uniquely designed, field-situated test recharge basin facility through which some 6...

  14. Novel dual-salts electrolyte solution for dendrite-free lithium-metal based rechargeable batteries with high cycle reversibility

    NASA Astrophysics Data System (ADS)

    Miao, Rongrong; Yang, Jun; Feng, Xuejiao; Jia, Hao; Wang, Jiulin; Nuli, Yanna

    2014-12-01

    Metallic lithium is the most promising negative electrode for high energy rechargeable batteries due to its extremely high specific capacity and the lowest redox potential. However, the low cycle efficiency and lithium dendrite formation during charge/discharge processes consistently hinder its practical application. Here a new dual-salts electrolyte composed of Li[N(SO2F)2] and Li[N(SO2CF3)2] has been explored to simultaneously cope with these two problems. Under the unique protection of solid electrolyte interphase (SEI) film formed in this electrolyte solution and the improvement in Li crystal growth pattern, high cycle efficiency of ca. 99% and dendrite-free Li deposit have been achieved. Moreover, the excellent cycling performance and favorable lithium morphology can be retained even at high current density of 10 mA cm-2. This study will greatly promote the development of Li-metal rechargeable batteries with high power and high energy density.

  15. Rechargeable Li-CO2 batteries with carbon nanotubes as air cathodes.

    PubMed

    Zhang, Xin; Zhang, Qiang; Zhang, Zhang; Chen, Yanan; Xie, Zhaojun; Wei, Jinping; Zhou, Zhen

    2015-10-01

    Rechargeable Li-CO2 batteries offer great promise by combining carbon capture and energy technology. However, the discharge product Li2CO3 is difficult to decompose upon recharging. In this work, carbon nanotubes (CNTs) with high electrical conductivity and porous three-dimensional networks were firstly explored as air cathodes for rechargeable Li-CO2 batteries. PMID:26290015

  16. 77 FR 2437 - Special Conditions: Gulfstream Aerospace Corporation, Model GVI Airplane; Rechargeable Lithium...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-18

    ... Privacy Act Statement can be found in the Federal Register published on April 11, 2000 (65 FR 19477-19478...; Rechargeable Lithium Batteries and Rechargeable Lithium- Battery Systems AGENCY: Federal Aviation... have a novel or unusual design feature associated with the installation of rechargeable...

  17. 76 FR 22161 - Second Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... Federal Aviation Administration Second Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries...: Notice of RTCA Special Committee 225 meeting: Rechargeable Lithium Batteries and Battery Systems--Small... Special Committee 225: Rechargeable Lithium Batteries and Battery Systems--Small and Medium Sizes....

  18. 76 FR 6180 - First Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-03

    ... Federal Aviation Administration First Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries...: Notice of RTCA Special Committee 225 meeting: Rechargeable Lithium Batteries and Battery Systems--Small... Special Committee 225: Rechargeable Lithium Batteries and Battery Systems--Small and Medium Sizes....

  19. 76 FR 38741 - Third Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ... Federal Aviation Administration Third Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries...: Notice of RTCA Special Committee 225 meeting: Rechargeable Lithium Batteries and Battery Systems--Small... Special Committee 225: Rechargeable Lithium Batteries and Battery Systems--Small and Medium Sizes....

  20. 76 FR 54527 - Fourth Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-01

    ... Federal Aviation Administration Fourth Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries...: Notice of RTCA Special Committee 225 meeting: Rechargeable Lithium Batteries and Battery Systems--Small... Special Committee 225: Rechargeable Lithium Batteries and Battery Systems--Small and Medium Sizes....

  1. PRINCIPALS OF ORGANIC CONTAMINANT BEHAVIOR DURING ARTIFICIAL RECHARGE

    EPA Science Inventory

    The behavior of a variety of organic contaminants having low molecular weight has been observed during groundwater recharge with reclaimed water. The evidence is site-specific, but is believed to have broader implications regarding the general behavior of organic contaminants in ...

  2. Rechargeable lithium batteries in the Navy -- Policy and protocol

    SciTech Connect

    Banner, J.A.; Winchester, C.S.

    1996-12-31

    Rechargeable lithium batteries are an emerging technology that is finding widespread use in myriad applications. These batteries are supplanting many others because of superior performance characteristics, including high energy density and improved cycle life. The newest model laptop computers, camcorders and cellular phones are using these systems to provide lighter products with longer battery life. Potential military-use scenarios for this technology range from propulsion power for autonomous unmanned vehicles to power sources for exercise mines. Current battery chemistries that might eventually be replaced by rechargeable lithium batteries include silver-zinc batteries, lithium-thionyl chloride batteries, and possibly lithium thermal batteries. The Navy is developing and implementing a universal test protocol for evaluating the safety characteristics of rechargeable lithium power sources, as discussed by Winchester et al (1995). Test plans based on this protocol are currently being used to evaluate both commercially available and developmental products. In this paper the authors will review the testing protocol that has been developed for evaluating the safety of rechargeable lithium batteries. Relevant data from current test programs will be presented.

  3. DELINEATING KARST RECHARGE AREAS AT ONONDAGA CAVE STATE PARK

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Onondaga Cave State Park is located in the north central portion of the Ozarks near Leasburg, Missouri. The park is known for two extensive cave systems, Onondaga Cave and Cathedral Cave. Both of these cave systems have active streams (1-2 cfs at baseflow) which have unknown recharge areas. As a man...

  4. Effects of variations in recharge on groundwater quality

    USGS Publications Warehouse

    Whittemore, D.O.; McGregor, K.M.; Marotz, G.A.

    1989-01-01

    The predominant regional effect of recharge on municipal groundwater quality in Kansas is the dilution of mineralized water in aquifers with relatively shallow water tables. The individual dissolved constituents contributing most to the water-quality variations are sulfate and chloride, and the calcium and sodium accompanying them, which are derived from the dissolution of evaporite minerals within the aquifer or from saline formation water in bedrock underlying the aquifer. The relationship between recharge and groundwater-quality variation can be quantified by associating certain climatic indices, especially the Palmer Drought Index, with quality observations. The response time of the maximum water-quality change relative to the occurrence of drought or substantial recharge ranges from a month to 3 years depending on the aquifer characteristics, and is generally proportional to the saturated thickness and specific yield. The response time is also affected by discharge to and recharge from nearby streams and by the well construction, particularly the placement of the screened interval, and pumping stress. ?? 1989.

  5. Implantable wireless battery recharging system for bladder pressure chronic monitoring.

    PubMed

    Young, Darrin J; Cong, Peng; Suster, Michael A; Damaser, Margot

    2015-11-21

    This paper presents an implantable wireless battery recharging system design for bladder pressure chronic monitoring. The wireless recharging system consists of an external 15 cm-diameter 6-turn powering coil and a silicone-encapsulated implantable rectangular coil with a dimension of 7 mm × 17 mm × 2.5 mm and 18 turns, which further encloses a 3 mm-diameter and 12 mm-long rechargeable battery, two ferrite rods, an ASIC, and a tuning capacitor. For a constant recharging current of 100 μA, an RF power of 700 μW needs to be coupled into the implantable module through the tuned coils. Analyses and experiments confirm that with the two coils aligned coaxially or with a 6 cm axial offset and a tilting angle of 30°, an external power of 3.5 W or 10 W is required, respectively, at an optimal frequency of 3 MHz to cover a large implant depth of 20 cm. PMID:26419677

  6. WASTEWATER CONTAMINATE REMOVAL FOR GROUNDWATER RECHARGE AT WATER FACTORY 21

    EPA Science Inventory

    This is the second report in a series which describes the performance of Water Factory 21, a 0.66 cu m/s advanced wastewater treatment plant designed to reclaim secondary effluent from a municipal wastewater treatment plant so that it can be used for injection and recharge of a g...

  7. Trench infiltration for managed aquifer recharge to permeable bedrock

    USGS Publications Warehouse

    Heilweil, V.M.; Watt, D.E.

    2011-01-01

    Managed aquifer recharge to permeable bedrock is increasingly being utilized to enhance resources and maintain sustainable groundwater development practices. One such target is the Navajo Sandstone, an extensive regional aquifer located throughout the Colorado Plateau of the western United States. Spreading-basin and bank-filtration projects along the sandstone outcrop's western edge in southwestern Utah have recently been implemented to meet growth-related water demands. This paper reports on a new cost-effective surface-infiltration technique utilizing trenches for enhancing managed aquifer recharge to permeable bedrock. A 48-day infiltration trench experiment on outcropping Navajo Sandstone was conducted to evaluate this alternative surface-spreading artificial recharge method. Final infiltration rates through the bottom of the trench were about 0.5 m/day. These infiltration rates were an order of magnitude higher than rates from a previous surface-spreading experiment at the same site. The higher rates were likely caused by a combination of factors including the removal of lower permeability soil and surficial caliche deposits, access to open vertical sandstone fractures, a reduction in physical clogging associated with silt and biofilm layers, minimizing viscosity effects by maintaining isothermal conditions, minimizing chemical clogging caused by carbonate mineral precipitation associated with algal photosynthesis, and diminished gas clogging associated with trapped air and biogenic gases. This pilot study illustrates the viability of trench infiltration for enhancing surface spreading of managed aquifer recharge to permeable bedrock. ?? 2010.

  8. Managed Aquifer Recharge in Italy: present and prospects.

    NASA Astrophysics Data System (ADS)

    Rossetto, Rudy

    2015-04-01

    On October the 3rd 2014, a one-day Workshop on Managed Aquifer Recharge (MAR) experiences in Italy took place at the GEOFLUID fair in Piacenza. It was organized within the framework of the EIP AG 128 - MAR Solutions - Managed Aquifer Recharge Strategies and Actions and the EU FPVII MARSOL. The event aimed at showcasing present experiences on MAR in Italy while at the same time starting a network among all the Institutions involved. In this contribution, we discuss the state of MAR application in Italy and summarize the outcomes of that event. In Italy aquifer recharge is traditionally applied unintentionally, by increasing riverbank filtration or because of excess irrigation. A certain interest for artificial recharge of aquifers arose at the end of the '70s and the beginning of the '80s and tests have been carried out in Tuscany, Veneto and Friuli Venezia Giulia. During the last years some projects on aquifer recharge were co-financed by the European Commission mainly through the LIFE program. Nearly all of them use the terminology of artificial recharge instead of MAR. They are: - TRUST (Tool for regional - scale assessment of groundwater storage improvement in adaptation to climate change, LIFE07 ENV/IT/000475; Marsala 2014); - AQUOR (Implementation of a water saving and artificial recharging participated strategy for the quantitative groundwater layer rebalance of the upper Vicenza's plain - LIFE 2010 ENV/IT/380; Mezzalira et al. 2014); - WARBO (Water re-born - artificial recharge: innovative technologies for the sustainable management of water resources, LIFE10 ENV/IT/000394; 2014). While the TRUST project dealt in general with aquifer recharge, AQUOR and WARBO focused essentially on small scale demonstration plants. Within the EU FPVII-ENV-2013 MARSOL project (Demonstrating Managed Aquifer Recharge as a Solution to Water Scarcity and Drought; 2014), a dedicated monitoring and decision support system is under development to manage recharge at a large scale riverbank filtration plant, worth 15 Mm3/year in Lucca (Tuscany; Borsi et al. 2014). In 2014, the Regional Authority of Emilia Romagna started a pilot on the Marecchia River fan using a recharge basin to alleviate water scarcity in the Rimini area as results of drought periods (Severi et al. 2014). To apply MAR techniques on a large scale is of particular interest the possibility to allow farmer's associations or drainage consortiums to play an important role in storing excess rainfall water in aquifers. Few hectares of land in rural areas may be dedicated to MAR plants, transforming a traditionally water consumer sector in one preserving it - opportunities are then linked to the provision of water related ecosystem services. Aquifer recharge is allowed in Italy only since September 2013, but still a regulatory framework is missing. Hopefully, this regulatory scheme will benefit from previous and on-going experiences. Dissemination of MAR scientific findings and technical know-how among governing authorities and the general public is crucial for the application of MAR techniques. Fundings for setting up new MAR plants may be available at national level. At the same time, lack of knowledge at intermediate governing bodies level is preventing the application of these techniques (i.e. building of small dams is favored although less convenient by several points of view in respect of MAR plants). Finally, it is of outmost importance to define which are the financial instruments to sustain these water infrastructures, so to guarantee not only their set up, but also routinely operations, opening as such a new market in the water sector. Acknowledgments This paper is co-financed within the framework of the EU FP7-ENV-2013-WATER-INNO-DEMO MARSOL (Grant Agreement n. 619120). References Borsi, I., Mazzanti, G., Barbagli, A., Rossetto, R., 2014. The riverbank filtration plant in S. Alessio (Lucca): monitoring and modeling activity within EU the FP7 MARSOL project. Acque Sotterranee - Italian Journal of Groundwater, Vol. 3, n. 3/137 Marsala, V. (2014). LIFE+ TRUST project: tool to assist the implementation of the Framework Directive 2000/60/CE, methodology and results. Acque Sotterranee - Italian Journal of Groundwater, Vol. 3, n. 3/137 MARSOL (2014). Demonstrating Managed Aquifer Recharge as a Solution to Water Scarcity and Drought www.marsol.eu [accessed 4 January 2015] Mezzalira, G., Niceforo, U., Gusmaroli, G. (2014). Forested infiltration areas (FIA); principles, experiences, perspectives. Acque Sotterranee - Italian Journal of Groundwater, Vol. 3, n. 3/137 Severi, P., Bonzi, L., Ferrari, V., Pellegrino, I. (2014). Managed aquifer recharge in the Marecchia alluvial fan (Rimini - Italy), start of the test and first results. Acque Sotterranee - Italian Journal of Groundwater, Vol. 3, n. 3/137 WARBO, 2014. WATER RE-BORN - Artificial Recharge. Innovative Technologies for the Sustainable Management of Water Resources. http://www.warbo-life.eu/ [accessed 8 August 2014

  9. LOCALIZED RECHARGE INFLUENCES ON MTBE TRANSPORT AND WELL PLACEMENT CONSIDERATIONS

    EPA Science Inventory

    Vertical characterization of a gasoline release site at East Patchogue, New York showed that methyl tert-butyl ether (MTBE) and aromatic plumes "dived" as they passed beneath a sand pit. That this behavior was caused by aquifer recharge was shown by two pieces of evidence. Fir...

  10. Estimating High Plains Aquifer Recharge Using Temperature Probes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The magnitude of recharge through playa wetlands in the High Plains Region of the United States has been debated, but rarely quantified. The ephemeral nature of water in playas makes it difficult and expensive to observe filling and drying/draining cycles. Inexpensive tools are needed to quantify ...

  11. Climate change effects on vegetation characteristics and groundwater recharge

    NASA Astrophysics Data System (ADS)

    Bartholomeus, R.; Voortman, B.; Witte, J.

    2010-12-01

    Climate change is among the most pressing issues of our time. Increase in temperature, a decrease in summer precipitation and increase in reference evapotranspiration might affect the water balance, freshwater availability and the spatial distribution and type of vegetation. Precipitation and evapotranspiration (ET) largely determine groundwater recharge. Therefore, climate change likely affects both the spatial and temporal freshwater availability for nature conservation, agriculture and drinking water supply. Moreover, in the coastal (dune) areas, the groundwater recharge is crucial to the maintenance of the freshwater bell and the dynamics of the fresh - salt interface. Current knowledge, however, is insufficient to estimate reliably the effects of climate change on future freshwater availability. Future groundwater recharge, the driving force of the groundwater system, can only be assessed if we understand how vegetation responds to changing climatic conditions, and how vegetation feedbacks on groundwater recharge through altered actual ET. Although the reference ET (i.e. the ET of a reference vegetation, defined as a short grassland completely covering the soil and optimally provided by water) is predicted to increase, the future actual ET (i.e. the ET of the actual ‘real’ vegetation under the ‘real’ moisture conditions) is highly unknown. It is the dynamics in the actual ET, however, through which the vegetation feeds back on the groundwater recharge. In an earlier study we showed that increased atmospheric CO2 raises the water use efficiency of plants, thus reducing ET. Here we demonstrate another important vegetation feedback in dune systems: the fraction of bare soil and non-rooting species (lichens and mosses) in the dune vegetation will increase when, according to the expectations, summers become drier. From our calculations it appeared that on south slopes of dunes, which receive more solar radiation and are warmer than north facing surfaces, the fraction of vascular plants may drop from 70 to 20 percent in the future (2050) climate due to increased moisture deficits. ET of bare soil and non-rooting species is much lower than that of vascular plants and thus the vegetation composition feeds back on the soil moisture conditions. Knowledge on such feedback mechanisms is indispensable in the analysis of climate change effects on the future groundwater recharge. Important questions are how, in the course of time, climate change will affect both groundwater table depth and dynamics, and how water management could adapt to these changes. We pursue a dynamic modeling approach that takes account of the interacting processes in the soil-plant-atmosphere system, including feedback mechanisms of the vegetation. This allows us to analyze climate change effects on groundwater recharge and thus future freshwater availability.

  12. Ecohydrologic process modeling of mountain block groundwater recharge.

    PubMed

    Magruder, Ian A; Woessner, William W; Running, Steve W

    2009-01-01

    Regional mountain block recharge (MBR) is a key component of alluvial basin aquifer systems typical of the western United States. Yet neither water scientists nor resource managers have a commonly available and reasonably invoked quantitative method to constrain MBR rates. Recent advances in landscape-scale ecohydrologic process modeling offer the possibility that meteorological data and land surface physical and vegetative conditions can be used to generate estimates of MBR. A water balance was generated for a temperate 24,600-ha mountain watershed, elevation 1565 to 3207 m, using the ecosystem process model Biome-BGC (BioGeochemical Cycles) (Running and Hunt 1993). Input data included remotely sensed landscape information and climate data generated with the Mountain Climate Simulator (MT-CLIM) (Running et al. 1987). Estimated mean annual MBR flux into the crystalline bedrock terrain is 99,000 m(3) /d, or approximately 19% of annual precipitation for the 2003 water year. Controls on MBR predictions include evapotranspiration (radiation limited in wet years and moisture limited in dry years), soil properties, vegetative ecotones (significant at lower elevations), and snowmelt (dominant recharge process). The ecohydrologic model is also used to investigate how climatic and vegetative controls influence recharge dynamics within three elevation zones. The ecohydrologic model proves useful for investigating controls on recharge to mountain blocks as a function of climate and vegetation. Future efforts will need to investigate the uncertainty in the modeled water balance by incorporating an advanced understanding of mountain recharge processes, an ability to simulate those processes at varying scales, and independent approaches to calibrating MBR estimates. PMID:19702780

  13. Defining Flood Recharge Processes: Lower Bill Williams River, Western Arizona

    NASA Astrophysics Data System (ADS)

    Simpson, S. C.; Meixner, T.; Hogan, J.

    2008-12-01

    River networks provide hydrologic connections between upland and headwater catchments and downstream reaches. In arid and semi-arid regions, full connectivity of a river system is rare and moments of connection may only occur during large flood events. Here we investigate the Bill Williams River, among the most arid river basins in the United States. The aridity of this system-and the associated lack of complicating hillslope processes adjacent to the river-provides a unique opportunity to study flood recharge processes in relative isolation. During all but the highest flows, the river infiltrates completely at the east end of Planet Valley and reemerges at the west end where it enters the Bill Williams River National Wildlife Refuge (NWR). Determining the source of baseflow in the lower Bill Williams/NWR, and the residence time of this water in the Planet Valley aquifer, will provide insight into the dependence of streamflow on earlier recharge-inducing floods. Defining this dependence more clearly is the next step toward a detailed knowledge of the long-term, basin-scale impacts of floods on water quality and quantity. To determine the impact of floods and the recharge they induce, surface and groundwater samples were collected during high and low flows throughout the basin from April 2007 through the present. Isotopic (δ18OH2O, δ2HH2O) and chemical differences (most notably SO4) in streamflow and groundwater along the system indicate the importance of older groundwater in NWR baseflow-either in the form of prior flood recharge or influxes from local springs. Sulfate isotope analysis (δ34SSO4, δ18OSO4) is pending for samples throughout the lower basin and this information should allow streamflow sources to be defined and quantified. This study provides a better characterization of the hydrologic and hydrochemical behavior of a Basin and Range river, and allows the effects of flood recharge processes to be more clearly defined at the basin scale.

  14. Enhanced recharge and karst, Edwards aquifer, south central Texas

    SciTech Connect

    Hammond, W.W. Jr. . Center for Water Research)

    1993-02-01

    Enhanced recharge is a water management strategy which can add significant quantities of ground water to the available water resources of the San Antonio region by utilizing the immense storage capacity of the unconfined zone of the Edwards aquifer. The Edwards aquifer presently is the sole source of water for a population of over 1,200,000, meeting public supply, industrial, and irrigation demands over a wide area of south central Texas. Valdina Farms Sinkhole is located adjacent to Seco Creek in Medina County and is in the recharge zone of the aquifer. Initial studies indicated that the sinkholes was capable of taking flood flows from Seco Creek and functioning as a recharge structure. Stream channels in the cavern system associated with Valdina Farms Sinkhole were incised into cave deposits and flood debris was present in the caverns at some distance from the sinkhole. Chemical analyses of samples of water from the cave and from nearby wells showed nitrate concentrations that decreased with distance from the cavern. Gradient of the potentiometric surface in the vicinity of the cave was very low, indicating high values of hydraulic conductivity for the aquifer. Based on evidence from these field studies a dam was constructed in 1982 on Seco Creek and a flood diversion channel was excavated to the sinkhole. Reservoir capacity is 2 acre-feet and design recharge rate is 3.8-6.7 m[sup 3]/sec. Annual recharge at the sinkhole has varied from 0 during periods of low runoff to 12,915 acre-feet.

  15. Groundwater suitability recharge zones modelling - A GIS application

    NASA Astrophysics Data System (ADS)

    Dabral, S.; Bhatt, B.; Joshi, J. P.; Sharma, N.

    2014-11-01

    Groundwater quality in Gujarat state is highly variable and due to multiplicity of factors viz. influenced by direct sea water encroachment, inherent sediment salinity, water logging, overexploitation leading to overall deterioration in ground water quality, coupled with domestic and industrial pollution etc. The groundwater scenario in the state is not very encouraging due to imbalance between recharge and groundwater exploitation. Further, the demand for water has increased manifold owing to agricultural, industrial and domestic requirement and this has led to water scarcity in many parts of the state, which is likely to become more severe in coming future due to both natural and manmade factors. Therefore, sustainable development of groundwater resource requires precise quantitative assessment based on reasonably valid scientific principles. Hence, delineation of groundwater potential zones (GWPZ), has acquired great significance. The present study focuses on the integrated Geospatial and Multi-Criteria Decision Making (MCDM) techniques to determine the most important contributing factors that affect the groundwater resources and also to delineate the potential zones for groundwater recharge. The multiple thematic layers of influencing parameters viz. geology, geomorphology, soil, slope, drainage density and land use, weightages were assigned to the each factor according to their relative importance as per subject experts opinion owing to the natural setup of the region. The Analytical Hierarchy Process (AHP) was applied to these factors and potential recharge zones were identified. The study area for the assessment of groundwater recharge potential zones is Mahi-Narmada inter-stream region of Gujarat state. The study shows that around 28 % region has the excellent suitability of the ground water recharge.

  16. Groundwater recharge measurements in gravel sandy sediments with monolith lysimeter

    NASA Astrophysics Data System (ADS)

    Bracic Zeleznik, Branka; Souvent, Petra; Cencur Curk, Barbara; Zupanc, Vesna

    2013-04-01

    Ljubljana field aquifer is recharging through precipitation and the river Sava, which has the snow-rain flow regime. The sediments of the aquifer have high permeability and create fast flow as well as high regeneration of the dynamic reserves of the Ljubljana field groundwater resource. Groundwater recharge is vulnerable to climate change and it is very important for drinking water supply management. Water stored in the soil and less permeable layers is important for water availability under extreme weather conditions. Measurements of water percolation through the vadose zone provide important input for groundwater recharge assessment and estimation of contaminant migration from land surface to the groundwater. Knowledge of the processes governing groundwater recharge in the vadose zone is critical to understanding the overall hydrological cycle and quantifying the links between land uses and groundwater quantity and quality. To improve the knowledge on water balance for Ljubljana field aquifer we establish a lysimeter for measurements of processes in unsaturated zone in well field Kleče. The type of lysimeter is a scientific lysimeter designed to solve the water balance equation by measuring the mass of the lysimeter monolith as well as that of outflow tank with high accuracy and high temporal resolution. We evaluated short period data, however the chosen month demonstrates weather extremes of the local climate - relatively dry periods, followed by high precipitation amount. In time of high water usage of vegetation only subsequent substantial precipitation events directly results in water flow towards lower layers. At the same time, gravely layers of the deeper parts of the unsaturated zone have little or no capacity for water retention, and in the event that water line leaves top soil, water flow moves downwards fairly quickly. On one hand this confirms high recharge capacity of Ljubljana field aquifer from precipitation on green areas; on the other hand it shows tremendous susceptibility of the aquifer to pollution and reinforces the position of groundwater protection zones above aquifer.

  17. New high capacity cathode materials for rechargeable Li-ion batteries: vanadate-borate glasses.

    PubMed

    Afyon, Semih; Krumeich, Frank; Mensing, Christian; Borgschulte, Andreas; Nesper, Reinhard

    2014-01-01

    V2O5 based materials are attractive cathode alternatives due to the many oxidation state switches of vanadium bringing about a high theoretical specific capacity. However, significant capacity losses are eminent for crystalline V2O5 phases related to the irreversible phase transformations and/or vanadium dissolution starting from the first discharge cycle. These problems can be circumvented if amorphous or glassy vanadium oxide phases are employed. Here, we demonstrate vanadate-borate glasses as high capacity cathode materials for rechargeable Li-ion batteries for the first time. The composite electrodes of V2O5 - LiBO(2) glass with reduced graphite oxide (RGO) deliver specific energies around 1000 Wh/kg and retain high specific capacities in the range of ~ 300 mAh/g for the first 100 cycles. V2O5 - LiBO(2) glasses are considered as promising cathode materials for rechargeable Li-ion batteries fabricated through rather simple and cost-efficient methods. PMID:25408200

  18. A Fully Integrated Wireless System for Intracranial Direct Cortical Stimulation, Real-Time Electrocorticography Data Transmission, and Smart Cage for Wireless Battery Recharge

    PubMed Central

    Piangerelli, Marco; Ciavarro, Marco; Paris, Antonino; Marchetti, Stefano; Cristiani, Paolo; Puttilli, Cosimo; Torres, Napoleon; Benabid, Alim Louis; Romanelli, Pantaleo

    2014-01-01

    Wireless transmission of cortical signals is an essential step to improve the safety of epilepsy procedures requiring seizure focus localization and to provide chronic recording of brain activity for Brain Computer Interface (BCI) applications. Our group developed a fully implantable and externally rechargeable device, able to provide wireless electrocorticographic (ECoG) recording and cortical stimulation (CS). The first prototype of a wireless multi-channel very low power ECoG system was custom-designed to be implanted on non-human primates. The device, named ECOGIW-16E, is housed in a compact hermetically sealed Polyether ether ketone (PEEK) enclosure, allowing seamless battery recharge. ECOGIW-16E is recharged in a wireless fashion using a special cage designed to facilitate the recharge process in monkeys and developed in accordance with guidelines for accommodation of animals by Council of Europe (ETS123). The inductively recharging cage is made up of nylon and provides a thoroughly novel experimental setting on freely moving animals. The combination of wireless cable-free ECoG and external seamless battery recharge solves the problems and shortcomings caused by the presence of cables leaving the skull, providing a safer and easier way to monitor patients and to perform ECoG recording on primates. Data transmission exploits the newly available Medical Implant Communication Service band (MICS): 402–405 MHz. ECOGIW-16E was implanted over the left sensorimotor cortex of a macaca fascicularis to assess the feasibility of wireless ECoG monitoring and brain mapping through CS. With this device, we were able to record the everyday life ECoG signal from a monkey and to deliver focal brain stimulation with movement elicitation. PMID:25202300

  19. Comparison of surface and groundwater balance approaches in the evaluation of managed aquifer recharge structures: Case of a percolation tank in a crystalline aquifer in India

    NASA Astrophysics Data System (ADS)

    Boisson, A.; Baïsset, M.; Alazard, M.; Perrin, J.; Villesseche, D.; Dewandel, B.; Kloppmann, W.; Chandra, S.; Picot-Colbeaux, G.; Sarah, S.; Ahmed, S.; Maréchal, J. C.

    2014-11-01

    To face the problem of groundwater depletion, the Indian Government relies on large projects of Managed Aquifer Recharge (MAR). Numerous recharge structures such as percolation tanks exist but the impact of these structures on groundwater resources remains poorly understood. Although the evaporation/infiltration ratio of percolation tanks was determined in several studies in semi-arid contexts using surface water balance methods, few studies evaluated the impact on the aquifer recharge. However, knowledge on recharge dynamics over time and space is essential for (1) the quantitative evaluation of stored water volumes, (2) the identification of beneficiaries (farmers) and (3) the estimation of percolation tanks recharge zone to the extent that is required to define proper management regulations at basin scale. These three points are of prime importance in the case of semi-arid regions where a limited number of rain events determine the water stored over the entire year. Assessment of the stored groundwater is even more difficult in crystalline aquifers due to the heterogeneous structure of flow paths. To date no methodological guidelines exist for local assessment of percolation tanks in crystalline aquifers. In this paper, we develop a method for calculating a local groundwater budget and we compare it with a computed surface balance. The method is applied to a case study in semi-arid crystalline context. From the groundwater balance we draw conclusions on (1) the limited amount of stored water in the aquifer, (2) the delayed recharge of the aquifer highlighting temporary storage/slow groundwater movement in the unsaturated zone and (3) the limited number of beneficiaries in years of medium monsoon rainfall. These results complement the understanding of the hydrodynamic functioning of percolation tanks, and their impact on the local groundwater balance.

  20. Monitoring induced denitrification in an artificial aquifer recharge system.

    NASA Astrophysics Data System (ADS)

    Grau-Martinez, Alba; Torrentó, Clara; Folch, Albert; Domènech, Cristina; Otero, Neus; Soler, Albert

    2014-05-01

    As demands on groundwater increase, artificial recharge is becoming a common method for enhancing groundwater supply. The Llobregat River is a strategic water supply resource to the Barcelona metropolitan area (Catalonia, NE Spain). Aquifer overexploitation has leaded to both a decrease of groundwater level and seawater intrusion, with the consequent deterioration of water quality. In the middle section of the aquifer, in Sant Vicenç del Horts, decantation and infiltration ponds recharged by water from the Llobregat River (highly affected from wastewater treatment plant effluents), were installed in 2007, in the framework of the ENSAT Life+ project. At the bottom of the infiltration pond, a vegetal compost layer was installed to promote the growth of bacteria, to induce denitrification and to create favourable conditions for contaminant biodegradation. This layer consists on a mixture of compost, aquifer material, clay and iron oxide. Understanding the fate of contaminants, such as nitrate, during artificial aquifer recharge is required to evaluate the impact of artificial recharge in groundwater quality. In order to distinguish the source of nitrate and to evaluate the capability of the organic reactive layer to induce denitrification, a multi-isotopic approach coupled with hydrogeochemical data was performed. Groundwater samples, as well as river samples, were sampled during artificial and natural recharge periods. The isotopic analysis included: δ15N and δ18O of dissolved nitrate, δ34S and δ18O of dissolved sulphate, δ13C of dissolved inorganic carbon, and δ2H and δ18O of water. Dissolved nitrate isotopic composition (δ15NNO3 from +9 to +21 o and δ18ONO3 from +3 to +16 ) demonstrated that heterotrophic denitrification induced by the reactive layer was taking place during the artificial recharge periods. An approximation to the extent of nitrate attenuation was calculated, showing a range between 95 and 99% or between 35 and 45%, by using the extreme literature ɛN values of -4o and -22o respectively (Aravena and Robertson, 1998; Pauwels et al., 2000). Ongoing denitrification batch experiments will allow us to determine the specific nitrogen and oxygen isotopic fractionation induced by the organic reactive layer, in order to estimate more precisely the extent of denitrification during artificial aquifer recharge. These results confirmed that the reactive layer induces denitrification in the recharge ponds area, proving the usefulness of an isotopic approach to characterize water quality improvement occurring during artificial aquifer recharge. References 1. Aravena, R., Robertson, W.D., 1998. Use of multiple isotope tracers to evaluate denitrification in ground water: Study of nitrate from a large-flux septic system plume. Ground Water, 36(6): 975-982. 2. Pauwels, H., J.C., Kloppmann, W., 2000. Denitrification and mixing in a schist aquifer: Influence on water chemistry and isotopes. Chemical Geology, 168(3-4): 307-324. Acknowledgment This study was supported by the projects CGL2011-29975-C04-01 from the Spanish Government, 2009SGR-00103 from the Catalan Government and ENPI/2011/280-008 from the European Commission. Please fill in your abstract text.

  1. Transient,spatially-varied recharge for groundwater modeling

    NASA Astrophysics Data System (ADS)

    Assefa, Kibreab; Woodbury, Allan

    2013-04-01

    This study is aimed at producing spatially and temporally varying groundwater recharge for transient groundwater modeling in a pilot watershed in the North Okanagan, Canada. The recharge modeling is undertaken by using a Richard's equation based finite element code (HYDRUS-1D) [Simunek et al., 2002], ArcGISTM [ESRI, 2011], ROSETTA [Schaap et al., 2001], in situ observations of soil temperature and soil moisture and a long term gridded climate data [Nielsen et al., 2010]. The public version of HYDUS-1D [Simunek et al., 2002] and another beta version with a detailed freezing and thawing module [Hansson et al., 2004] are first used to simulate soil temperature, snow pack and soil moisture over a one year experimental period. Statistical analysis of the results show both versions of HYDRUS-1D reproduce observed variables to the same degree. Correlation coefficients for soil temperature simulation were estimated at 0.9 and 0.8, at depths of 10 cm and 50 cm respectively; and for soil moisture, 0.8 and 0.6 at 10 cm and 50 cm respectively. This and other standard measures of model performance (root mean square error and average error) showed a promising performance of the HYDRUS-1D code in our pilot watershed. After evaluating model performance using field data and ROSETTA derived soil hydraulic parameters, the HYDRUS-1D code is coupled with ArcGISTM to produce spatially and temporally varying recharge maps throughout the Deep Creek watershed. Temporal and spatial analysis of 25 years daily recharge results at various representative points across the study watershed reveal significant temporal and spatial variations; average recharge estimated at 77.8 ± 50.8mm /year. This significant variation over the years, caused by antecedent soil moisture condition and climatic condition, illustrates the common flaw of assigning a constant percentage of precipitation throughout the simulation period. Groundwater recharge modeling has previously been attempted in the Okanagan Basin and other parts of Canada by using the HELP code. However, HELP has known limitations related with boundary conditions as well as spatial and temporal discretization options, and thus cannot simulate highly variable fluxes near boundaries. The limitations are even more pronounced in semi-arid areas like the Okanagan Basin where upward fluxes can be high, because HELP assumes that water below evaporative zone simply drains to the base of a soil column without accounting for upward fluxes. In addition to these limitations, previous studies that used HELP for recharge estimation, [Towes and Allen, 2009; Jyrkama and Sykes, 2007], did not attempt to verify model performance in their study area. The study here presents an integrated procedure that can help address some of these often neglected modelling challenges. The significance of the method in transient groundwater modeling is demonstrated by applying the spatially and temporally varying recharge boundary condition to a saturated zone groundwater model, MIKESHE [DHI, 2009a]. The water table simulated using this method is found to be within 0.6 m of the observed values, whereas the water levels estimated using uniform recharge boundary condition can fluctuate by as much as 1.6 m. Root mean square errors were estimated at 0.3 and 0.94 respectively.

  2. Transient, spatially-varied recharge for groundwater modeling

    NASA Astrophysics Data System (ADS)

    Assefa, K.; Woodbury, A. D.

    2012-12-01

    This study is aimed at producing spatially and temporally varying groundwater recharge for transient groundwater modeling in a pilot watershed in the North Okanagan, Canada. The recharge modeling is undertaken by using a Richard's equation based finite element code (HYDRUS-1D) [Simunek et al., 2002], ArcGISTM [ESRI, 2011], ROSETTA [Schaap et al., 2001], in situ observations of soil temperature and soil moisture and a long term gridded climate data [Nielsen et al., 2010]. The public version of HYDUS-1D [Simunek et al., 2002] and another beta version with a detailed freezing and thawing module [Hansson et al., 2004] are first used to simulate soil temperature, snow pack and soil moisture over a one year experimental period. Statistical analysis of the results show both versions of HYDRUS-1D reproduce observed variables to the same degree. Correlation coefficients for soil temperature simulation were estimated at 0.9 and 0.8, at depths of 10 cm and 50 cm respectively; and for soil moisture, 0.8 and 0.6 at 10 cm and 50 cm respectively. This and other standard measures of model performance (root mean square error and average error) showed a promising performance of the HYDRUS-1D code in our pilot watershed. After evaluating model performance using field data and ROSETTA derived soil hydraulic parameters, the HYDRUS-1D code is coupled with ArcGISTM to produce spatially and temporally varying recharge maps throughout the Deep Creek watershed. Temporal and spatial analysis of 25 years daily recharge results at various representative points across the study watershed reveal significant temporal and spatial variations; average recharge estimated at 77.8 ± 50.8mm /year. This significant variation over the years, caused by antecedent soil moisture condition and climatic condition, illustrates the common flaw of assigning a constant percentage of precipitation throughout the simulation period. Groundwater recharge modeling has previously been attempted in the Okanagan Basin and other parts of Canada by using the HELP code. However, HELP has known limitations related with boundary conditions as well as spatial and temporal discretization options, and thus cannot simulate highly variable fluxes near boundaries. The limitations are even more pronounced in semi-arid areas like the Okanagan Basin where upward fluxes can be high, because HELP assumes that water below evaporative zone simply drains to the base of a soil column without accounting for upward fluxes. In addition to these limitations, previous studies that used HELP for recharge estimation, [Towes and Allen, 2009; Jyrkama and Sykes, 2007], did not attempt to verify model performance in their study area. The study here presents an integrated procedure that can help address some of these often neglected modelling challenges. The significance of the method in transient groundwater modeling is demonstrated by applying the spatially and temporally varying recharge boundary condition to a saturated zone groundwater model, MIKESHE [DHI, 2009a]. The water table simulated using this method is found to be within 0.6 m of the observed values, whereas the water levels estimated using uniform recharge boundary condition can fluctuate by as much as 1.6 m. Root mean square errors were estimated at 0.3 and 0.94 respectively.

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

    SciTech Connect

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

    1990-01-01

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

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

    NASA Astrophysics Data System (ADS)

    1990-01-01

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

  5. Hydrogeophysical characterization of shallow unconsolidated sediments for the artificial groundwater recharge in a water curtain cultivation area

    NASA Astrophysics Data System (ADS)

    Shin, Jehyun; Hwang, Seho; Won, Byeongho; Kim, Yongcheol

    2013-04-01

    A water curtain cultivation system is usually used to offer a stable heat source using a geothermal heat of groundwater. However, it may cause groundwater drawdown by an excessive use of groundwater such as over-pumping. Therefore, as part of an effort to develop a sustainable water curtain system, artificial groundwater recharge is projected to minimize groundwater shortage problem and recover groundwater level. Geophysical approaches are systematically applied to characterize unconsolidated sediments and riverside porous aquifers for the artificial groundwater recharge in a water curtain cultivation area. Resistivity survey is applied to map the distribution of subsurface structure, especially unconsolidated sediments. A series of test holes are drilled, and water level, temperature, and groundwater electrical conductivity are monitored to characterize hydrogeological properties of the site. The natural gamma and induction profiles enable us to estimate stratigraphic cross section and interpret inter-borehole. Borehole compensated neutron porosity is derived for a small-diameter, dual-detector neutron logs. Consequently, geophysical methods could enhance knowledge of the physical properties of unconsolidated sediments, and they are expected to evaluate injection feasibility of artificial groundwater recharge systems to the sustainable water resource management.

  6. Modelling perched river recharge to the Wairau aquifer, New Zealand

    NASA Astrophysics Data System (ADS)

    Wöhling, Thomas; Gosses, Moritz; Wilson, Scott; Davidson, Peter

    2015-04-01

    The Wairau Aquifer in Marlborough, New Zealand, consists of coarse, high-conductive alluvial gravels and is almost exclusively recharged by surface water from the braided Wairau River. Recent experimental evidence suggests that the river is perched in the upstream recharge region of the aquifer. The aquifer serves as the major drinking water resource for the city of Blenheim and the surrounding settlements on the Wairau Plain and thus is a key natural resource for the region. To ensure the sustainable management of the resource, it is essential to better understand the limits and the mechanics of the recharge mechanism. One efficient way to test hypotheses of the mechanisms for river-groundwater exchange fluxes between the Wairau river and aquifer is by data integration into numerical models that mimic the flow regime of the coupled hydrological system. For that purpose, a Modflow model for the Wairau Aquifer was to set up and calibrated under summer conditions when the flow in the river is low and the aquifer is most vulnerable to over-allocation. The model is constrained by knowledge about the hydrogeological settings as well as observations of groundwater levels, river and spring flow gaugings, and analysis of aquifer pumping tests. Both historic and more recent concurrent river flow measurements under low flow conditions suggest that approximately 7-8 m³/s is recharged into the aquifer along the upper and middle reaches, at least partly under perched conditions. At the eastern side of the aquifer, a small proportion of that water flows back into the river, whereas a greater proportion emerges in springs. Spring creek is the largest spring with an estimated mean flow of 4.0 m³/s. This flow rate is vulnerable to an excessive decline in groundwater levels. The simulations with the calibrated flow model fit well to the observations of current mean groundwater heads as well as to mean Wairau river and Spring creek flows. Modeling results suggest a large spatial variability of recharge fluxes along the river. Model calibration to the different data types turned out to be challenging and required a powerful multiobjective optimization approach and parameter regularization techniques. The proposed approach yielded parsimonious parameter fields with relatively low variability that are generally in agreement with estimations from bore-log analysis. First steps were taken to simulate the dynamics of the river recharge mechanisms and to evaluate the current monitoring scheme with respect to the utility of individual observations. Transient simulations under different flow regimes will improve the knowledge about the Wairau river-groundwater exchange fluxes and thus assist in providing more confidence in managing the valuable resource.

  7. Recharge Estimation Using Water, Chloride and Isotope Mass Balances

    NASA Astrophysics Data System (ADS)

    Dogramaci, S.; Firmani, G.; Hedley, P.; Skrzypek, G.; Grierson, P. F.

    2014-12-01

    Discharge of surplus mine water into ephemeral streams may elevate groundwater levels and alter the exchange rate between streams and underlying aquifers but it is unclear whether volumes and recharge processes are within the range of natural variability. Here, we present a case study of an ephemeral creek in the semi-arid subtropical Hamersley Basin that has received continuous mine discharge for more than five years. We used a numerical model coupled with repeated measurements of water levels, chloride concentrations and the hydrogen and oxygen stable isotope composition (δ2H and δ18O) to estimate longitudinal evapotranspiration and recharge rates along a 27 km length of Weeli Wolli Creek. We found that chloride increased from 74 to 120 mg/L across this length, while δ18O increased from -8.24‰ to -7.00‰. Groundwater is directly connected to the creek for the first 13 km and recharge rates are negligible. Below this point, the creek flows over a highly permeable aquifer and water loss by recharge increases to a maximum rate of 4.4 mm/d, which accounts for ~ 65% of the total water discharged to the creek. Evapotranspiration losses account for the remaining ~35%. The calculated recharge from continuous flow due to surplus water discharge is similar to that measured for rainfall-driven flood events along the creek. Groundwater under the disconnected section of the creek is characterised by a much lower Cl concentration and more depleted δ18O value than mining discharge water but is similar to flood water generated by large episodic rainfall events. Our results suggest that the impact of recharge from continuous flow on the creek has not extended beyond 27 km from the discharge point. Our approach using a combination of hydrochemical and isotope methods coupled with classical surface flow hydraulic modelling allowed evaluation of components of water budget otherwise not possible in a highly dynamic system that is mainly driven by infrequent but large episodic floods.

  8. Geophysical Methods for Improved Understanding of Managed Aquifer Recharge (Invited)

    NASA Astrophysics Data System (ADS)

    Pidlisecky, A.; Nenna, V.; Knight, R. J.

    2013-12-01

    Managed aquifer recharge is increasingly being used as a means of augmenting groundwater supplies. With the increased use, questions arise regarding the suitability of sites for such operations, as well as the operational efficiency of these systems. In this work we specifically look at MAR using an artificial recharge pond. There are two operational challenges commonly faced in artificial recharge ponds: 1) A decrease in infiltration rate of water into the subsurface during operating; this limits the amount of stored water. 2) Low recovery rates of the stored water. Addressing both of these challenges requires sufficient information about the spatial and temporal variation in governing hydrologic properties and processes. Geophysical methods provide a novel way of obtaining such information from the region beneath a recharge pond. A study of the Harkins Slough Recharge Pond, near Watsonville California, presented a unique opportunity to develop and test geophysical methods, specifically for improved understanding off MAR. At this site we deployed a series of geophysical sensors aimed at addressing the two operational challenges at the site. We first addressed the question: What is controlling the decrease in filtration rate? The development and installation of electrical conductivity probes beneath the pond allowed us to monitor changes in the top ~1 m over a 4-month period. This dataset revealed that clogging in the top ~10 cm was responsible for the decreased infiltration rate. These 1D data were augmented by a time-lapse 2D ERT dataset that shows significant lateral variability in infiltration at the site. The second question we addressed was: Why is the recovery rate so low? Using a combination of cone-penetrometer testing and seismic reflection data, we developed a subsurface model that suggested there was a thin clay layer that may be impeding the flow of water to the recovery wells. To further understand this, we developed electrical conductivity probes, containing pore pressure transducers, to monitor changes in electrical conductivity and fluid pressure to a depth of 30 m. The data acquired with these probes clearly showed that the subsurface clay layer was impeding flow to the screened zone of the recovery wells. The findings at the site demonstrate the value of geophysics obtaining information regarding the siting and operation of artificial recharge ponds.

  9. Alternative aircraft fuels

    NASA Technical Reports Server (NTRS)

    Longwell, J. P.; Grobman, J.

    1978-01-01

    In connection with the anticipated impossibility to provide on a long-term basis liquid fuels derived from petroleum, an investigation has been conducted with the objective to assess the suitability of jet fuels made from oil shale and coal and to develop a data base which will allow optimization of future fuel characteristics, taking energy efficiency of manufacture and the tradeoffs in aircraft and engine design into account. The properties of future aviation fuels are examined and proposed solutions to problems of alternative fuels are discussed. Attention is given to the refining of jet fuel to current specifications, the control of fuel thermal stability, and combustor technology for use of broad specification fuels. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source.

  10. Hybrid system for rechargeable magnesium battery with high energy density

    PubMed Central

    Chang, Zheng; Yang, Yaqiong; Wang, Xiaowei; Li, Minxia; Fu, Zhengwen; Wu, Yuping; Holze, Rudolf

    2015-01-01

    One of the main challenges of electrical energy storage (EES) is the development of environmentally friendly battery systems with high safety and high energy density. Rechargeable Mg batteries have been long considered as one highly promising system due to the use of low cost and dendrite-free magnesium metal. The bottleneck for traditional Mg batteries is to achieve high energy density since their output voltage is below 2.0 V. Here, we report a magnesium battery using Mg in Grignard reagent-based electrolyte as the negative electrode, a lithium intercalation compound in aqueous solution as the positive electrode, and a solid electrolyte as a separator. Its average discharge voltage is 2.1 V with stable discharge platform and good cycling life. The calculated energy density based on the two electrodes is high. These findings open another door to rechargeable magnesium batteries. PMID:26173624

  11. Novel electrolyte chemistries for Mg-Ni rechargeable batteries.

    SciTech Connect

    Garcia-Diaz, Brenda; Kane, Marie; Au, Ming

    2010-10-01

    Commercial hybrid electric vehicles (HEV) and battery electric vehicles (BEV) serve as means to reduce the nation's dependence on oil. Current electric vehicles use relatively heavy nickel metal hydride (Ni-MH) rechargeable batteries. Li-ion rechargeable batteries have been developed extensively as the replacement; however, the high cost and safety concerns are still issues to be resolved before large-scale production. In this study, we propose a new highly conductive solid polymer electrolyte for Mg-Ni high electrochemical capacity batteries. The traditional corrosive alkaline aqueous electrolyte (KOH) is replaced with a dry polymer with conductivity on the order of 10{sup -2} S/cm, as measured by impedance spectroscopy. Several potential novel polymer and polymer composite candidates are presented with the best-performing electrolyte results for full cell testing and cycling.

  12. Evaluation of slurry characteristics for rechargeable lithium-ion batteries

    SciTech Connect

    Cho, Ki Yeon; Kwon, Young Il; Youn, Jae Ryoun; Song, Young Seok

    2013-08-01

    Graphical abstract: - Highlights: • Lithium-ion battery slurries are prepared for rechargeable batteries. • The dispersion state of slurry constituents is identified. • Thermal, morphological, rheological, and electrical properties of slurries are analyzed. - Abstract: A multi-component slurry for rechargeable batteries is prepared by dispersing LiCoO{sub 2}, conductive additives, and polymeric binders in a solvent. The physical properties, including rheological, morphological, electrical, and spectroscopic features of battery slurries are investigated. The relationship between the measured physical properties and the internal structure of the slurry is analyzed. It is found that the rheological behavior of the slurry is determined by the interaction of active materials and binding materials (e.g., network structure) and that the dispersion state of conductive additives (e.g., agglomeration) also depends on the binder–carbon interaction.

  13. Hybrid system for rechargeable magnesium battery with high energy density

    NASA Astrophysics Data System (ADS)

    Chang, Zheng; Yang, Yaqiong; Wang, Xiaowei; Li, Minxia; Fu, Zhengwen; Wu, Yuping; Holze, Rudolf

    2015-07-01

    One of the main challenges of electrical energy storage (EES) is the development of environmentally friendly battery systems with high safety and high energy density. Rechargeable Mg batteries have been long considered as one highly promising system due to the use of low cost and dendrite-free magnesium metal. The bottleneck for traditional Mg batteries is to achieve high energy density since their output voltage is below 2.0 V. Here, we report a magnesium battery using Mg in Grignard reagent-based electrolyte as the negative electrode, a lithium intercalation compound in aqueous solution as the positive electrode, and a solid electrolyte as a separator. Its average discharge voltage is 2.1 V with stable discharge platform and good cycling life. The calculated energy density based on the two electrodes is high. These findings open another door to rechargeable magnesium batteries.

  14. Hybrid system for rechargeable magnesium battery with high energy density.

    PubMed

    Chang, Zheng; Yang, Yaqiong; Wang, Xiaowei; Li, Minxia; Fu, Zhengwen; Wu, Yuping; Holze, Rudolf

    2015-01-01

    One of the main challenges of electrical energy storage (EES) is the development of environmentally friendly battery systems with high safety and high energy density. Rechargeable Mg batteries have been long considered as one highly promising system due to the use of low cost and dendrite-free magnesium metal. The bottleneck for traditional Mg batteries is to achieve high energy density since their output voltage is below 2.0 V. Here, we report a magnesium battery using Mg in Grignard reagent-based electrolyte as the negative electrode, a lithium intercalation compound in aqueous solution as the positive electrode, and a solid electrolyte as a separator. Its average discharge voltage is 2.1 V with stable discharge platform and good cycling life. The calculated energy density based on the two electrodes is high. These findings open another door to rechargeable magnesium batteries. PMID:26173624

  15. Zinc electrode and rechargeable zinc-air battery

    DOEpatents

    Ross, Jr., Philip N.

    1989-01-01

    An improved zinc electrode is disclosed for a rechargeable zinc-air battery comprising an outer frame and a porous foam electrode support within the frame which is treated prior to the deposition of zinc thereon to inhibit the formation of zinc dendrites on the external surface thereof. The outer frame is provided with passageways for circulating an alkaline electrolyte through the treated zinc-coated porous foam. A novel rechargeable zinc-air battery system is also disclosed which utilizes the improved zinc electrode and further includes an alkaline electrolyte within said battery circulating through the passageways in the zinc electrode and an external electrolyte circulation means which has an electrolyte reservoir external to the battery case including filter means to filter solids out of the electrolyte as it circulates to the external reservoir and pump means for recirculating electrolyte from the external reservoir to the zinc electrode.

  16. Water quality management of aquifer recharge using advanced tools.

    PubMed

    Lazarova, Valentina; Emsellem, Yves; Paille, Julie; Glucina, Karl; Gislette, Philippe

    2011-01-01

    Managed aquifer recharge (MAR) with recycled water or other alternative resources is one of the most rapidly growing techniques that is viewed as a necessity in water-short areas. In order to better control health and environmental effects of MAR, this paper presents two case studies demonstrating how to improve water quality, enable reliable tracing of injected water and better control and manage MAR operation in the case of indirect and direct aquifer recharge. Two water quality management strategies are illustrated on two full-scale case studies, including the results of the combination of non conventional and advanced technologies for water quality improvement, comprehensive sampling and monitoring programs including emerging pollutants, tracer studies using boron isotopes and integrative aquifer 3D GIS hydraulic and hydrodispersive modelling. PMID:22214066

  17. Intrinsically safe 5-V, 4-A rechargeable power supply

    NASA Astrophysics Data System (ADS)

    Sammarco, John J.

    The U.S. Bureau of Mines has developed a regulated, intrinsically safe, rechargeable power supply for portable electronic equipment for underground use. The regulated output is ideal for microprocessor power requirements and is suited for operation in hazardous environments. Two rechargeable, sealed batteries are contained within the power supply. Provisions are made to use an external source of power if these batteries fail. Provisions are also made to charge these internal batteries when needed. The circuit is composed of three main circuits: the main regulator circuit, the input protection circuit, and the output protection circuit. The main regulator circuit provides remote voltage sensing, current sensing, fault monitoring, and internal thermal protection. The input protection circuit checks for excessive input current and low battery conditions. The output protection circuit contains two overvoltage detection devices. Schematics, a parts list, and a calibration procedure are provided in the report to enable readers to fabricate the power supply.

  18. Recharging behavior of nitrogen-centers in ZnO

    SciTech Connect

    Philipps, Jan M. Meyer, Bruno K.; Hofmann, Detlev M.; Stehr, Jan E.; Buyanova, Irina; Tarun, Marianne C.; McCluskey, Matthew D.

    2014-08-14

    Electron Paramagnetic Resonance was used to study N{sub 2}-centers in ZnO, which show a 5-line spectrum described by the hyperfine interaction of two nitrogen nuclei (nuclear spin I = 1, 99.6% abundance). The recharging of this center exhibits two steps, a weak onset at about 1.4 eV and a strongly increasing signal for photon energies above 1.9 eV. The latter energy coincides with the recharging energy of N{sub O} centers (substitutional nitrogen atoms on oxygen sites). The results indicate that the N{sub 2}-centers are deep level defects and therefore not suitable to cause significant hole-conductivity at room temperature.

  19. 12-Crown-4 Ether Improves Rechargeable Lithium Cells

    NASA Technical Reports Server (NTRS)

    Nagasubramanian, Ganesan; Attia, Alan I.

    1992-01-01

    Experiments show addition of 12-crown-4 ether (12Cr4) to thin film of polyethylene oxide (PEO) and LiBF4 reduces charge-transfer resistance of film and enhances performance of electrochemical cell in which film is electrolyte, anode is lithium, and cathode is LixCoO2. By increasing conductivity of the electrolyte, 12Cr4 reduces polarization loss; enabling cell to sustain higher current. Result is new type of rechargeable lithium cell.

  20. Estimating recharge at Yucca Mountain, Nevada: A case study

    SciTech Connect

    Flint, A.; Flint, L.; Kwicklis, E.; Fabryka-Martin, J.; Bodvarsson, G.S.

    2001-05-13

    Obtaining values of net infiltration, groundwater travel time, and recharge is necessary at the Yucca Mountain site, Nevada, USA, in order to evaluate the expected performance of a potential repository as a containment system for high-level radioactive waste. However, the geologic complexities of this site, its low precipitation and net infiltration, with numerous mechanisms operating simultaneously to move water through the system, provide many challenges for the estimation of the spatial distribution of recharge. A variety of methods appropriate for arid environments has been applied, including water-balance techniques, calculations using Darcy's law in the unsaturated zone, a soil-physics method applied to neutron-hole water-content data, inverse modeling of thermal profiles in boreholes extending through the thick unsaturated zone, chloride mass balance, atmospheric radionuclides, and empirical approaches. These methods indicate that near-surface infiltration rates at Yucca Mountain are highly variable in time and space, with local (point) values ranging from zero to several hundred millimeters per year. Spatially distributed net-infiltration values average 5 mm/year, with the highest values approaching 20 mm/year near Yucca Crest. Site-scale recharge estimates range from less than 1 to about 12 mm/year. These results have been incorporated into a site-scale model that has been calibrated using these data sets that reflect infiltration processes acting on highly variable temporal and spatial scales. The modeling study predicts highly non-uniform recharge at the water table, distributed significantly differently from the non-uniform infiltration pattern at the surface.

  1. Estimating recharge at yucca mountain, nevada, usa: comparison of methods

    SciTech Connect

    Flint, A. L.; Flint, L. E.; Kwicklis, E. M.; Fabryka-Martin, J. T.; Bodvarsson, G. S.

    2001-11-01

    Obtaining values of net infiltration, groundwater travel time, and recharge is necessary at the Yucca Mountain site, Nevada, USA, in order to evaluate the expected performance of a potential repository as a containment system for high-level radioactive waste. However, the geologic complexities of this site, its low precipitation and net infiltration, with numerous mechanisms operating simultaneously to move water through the system, provide many challenges for the estimation of the spatial distribution of recharge. A variety of methods appropriate for and environments has been applied, including water-balance techniques, calculations using Darcy's law in the unsaturated zone, a soil-physics method applied to neutron-hole water-content data, inverse modeling of thermal profiles in boreholes extending through the thick unsaturated zone, chloride mass balance, atmospheric radionuclides, and empirical approaches. These methods indicate that near-surface infiltration rates at Yucca Mountain are highly variable in time and space, with local (point) values ranging from zero to several hundred millimeters per year. Spatially distributed net-infiltration values average 5 mm/year, with the highest values approaching 20 nun/year near Yucca Crest. Site-scale recharge estimates range from less than I to about 12 mm/year. These results have been incorporated into a site-scale model that has been calibrated using these data sets that reflect infiltration processes acting on highly variable temporal and spatial scales. The modeling study predicts highly non-uniform recharge at the water table, distributed significantly differently from the non-uniform infiltration pattern at the surface. [References: 57

  2. Changes in vegetation diversity caused by artificial recharge

    USGS Publications Warehouse

    Van Hylckama, T. E. A.

    1979-01-01

    Efforst to increase the rate of artificial recharge through basins often necessitates scrapping and ditching before and during operations. Such operations can result in more or less drastic changes in vegetation (depending on what was there before), characterized by diminisched numbers of species and lowered diversity. Two examples, one from Texas and one from the Netherlands are presented showing how similar treatments cause similar changes in two completely difference plant communities. ?? 1979 Dr. W. Junk b.v. - Publishers.

  3. Estimating recharge at Yucca Mountain, Nevada, USA: Comparison of methods

    USGS Publications Warehouse

    Flint, A.L.; Flint, L.E.; Kwicklis, E.M.; Fabryka-Martin, J. T.; Bodvarsson, G.S.

    2002-01-01

    Obtaining values of net infiltration, groundwater travel time, and recharge is necessary at the Yucca Mountain site, Nevada, USA, in order to evaluate the expected performance of a potential repository as a containment system for high-level radioactive waste. However, the geologic complexities of this site, its low precipitation and net infiltration, with numerous mechanisms operating simultaneously to move water through the system, provide many challenges for the estimation of the spatial distribution of recharge. A variety of methods appropriate for arid environments has been applied, including water-balance techniques, calculations using Darcy's law in the unsaturated zone, a soil-physics method applied to neutron-hole water-content data, inverse modeling of thermal profiles in boreholes extending through the thick unsaturated zone, chloride mass balance, atmospheric radionuclides, and empirical approaches. These methods indicate that near-surface infiltration rates at Yucca Mountain are highly variable in time and space, with local (point) values ranging from zero to several hundred millimeters per year. Spatially distributed net-infiltration values average 5 mm/year, with the highest values approaching 20 mm/year near Yucca Crest. Site-scale recharge estimates range from less than 1 to about 12 mm/year. These results have been incorporated into a site-scale model that has been calibrated using these data sets that reflect infiltration processes acting on highly variable temporal and spatial scales. The modeling study predicts highly non-uniform recharge at the water table, distributed significantly differently from the non-uniform infiltration pattern at the surface.

  4. An accounting/recharge system for educational media services.

    PubMed

    Grover, P L; Lindstrom, R A

    1980-07-01

    An accounting/recharge system can aid the educational media manager in more efficient use of resources to accomplish organizational goals. A system for cataloging, billing, and analyzing the productivity and relative efficiency of media production and services is outlined. Benefits derived from such a system include an improved basis for planning and rationing of resources, greater efficiency in utilization and production, improved internal communications, and an increased sense of accomplishment. PMID:6156156

  5. Evaluation of Recharge Potential at Crater U5a (WISHBONE)

    SciTech Connect

    Richard H. French; Samuel L. Hokett

    1998-11-01

    Radionuclides are present both below and above the water table at the Nevada Test Site (NTS), as the result of underground nuclear testing. Mobilization and transport of radionuclides from the vadose zone is a complex process that is influenced by the solubility and sorption characteristics of the individual radionuclides, as well as the soil water flux. On the NTS, subsidence craters resulting from testing underground nuclear weapons are numerous, and many intercept surface water flows. Because craters collect surface water above the sub-surface point of device detonation, these craters may provide a mechanism for surface water to recharge the groundwater aquifer system underlying the NTS. Given this situation, there is a potential for the captured water to introduce contaminants into the groundwater system. Crater U5a (WISHBONE), located in Frenchman Flat, was selected for study because of its potentially large drainage area, and significant erosional features, which suggested that it has captured more runoff than other craters in the Frenchman Flat area. Recharge conditions were studied in subsidence crater U5a by first drilling boreholes and analyzing the collected soil cores to determine the soil properties and moisture conditions. This information, coupled with a 32-year precipitation record, was used to conduct surface and vaodse zone modeling. Surface water modeling predicted that approximately 13 ponding events had occurred during the life of the crater. Vadose zone modeling indicated that since the crater's formation approximately 5,900 m3 of water were captured by the crater. Of this total, approximately 5,200 m3 of potential recahrge may have occurred, and the best estimates of annual average potential recharge rates lie between 36 and 188 cm of water per year. The term potential is used here to indicate that the water is not technically recharged because it has not yet reached the water table.

  6. NiF2 Cathodes For Rechargeable Na Batteries

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V.; Distefano, Salvador; Halpert, Gerald

    1992-01-01

    Use of NiF2 cathodes in medium-to-high-temperature rechargeable sodium batteries increases energy and power densities by 25 to 30 percent without detracting from potential advantage of safety this type of sodium battery offers over sodium batteries having sulfur cathodes. High-energy-density sodium batteries with metal fluoride cathodes used in electric vehicles and for leveling loads on powerlines.

  7. Electrochemically Stable Cathode Current Collectors for Rechargeable Magnesium Batteries

    SciTech Connect

    Cheng, Yingwen; Liu, Tianbiao L.; Shao, Yuyan; Engelhard, Mark H.; Liu, Jun; Li, Guosheng

    2014-01-01

    Rechargeable Mg batteries are attractive energy storage systems and could bring cost-effective energy solutions. Currently, however, no practical cathode current collectors that can withstand high voltages in Mg2+ electrolytes has been identified and therefore cathode research is greatly hindered. Here we identified that two metals, Mo and W, are electrochemically stable through formation of surface passive layers. The presented results could have significant impacts on the developments of high voltage Mg batteries.

  8. Estimating areas contributing recharge to wells, lessons from previous studies

    USGS Publications Warehouse

    Franke, O. Lehn; Reilly, T.E.; Pollock, D.W.; LaBaugh, J.W.

    1998-01-01

    Factors relating to the estimation of areas contributing recharge to wells, such as complexity of the ground-water flow system, effects of changing hydrologic conditions, and effects of well-screen locations and pumping rates, are reviewed. The point of view that simulation is the best means to obtain physically based estimates of contributing areas is emphasized. An extensive list of USGS reports that include estimation of contributing areas is provided.

  9. The MOLICEL(R) rechargeable lithium system: Multicell battery aspects

    NASA Technical Reports Server (NTRS)

    Fouchard, D.; Taylor, J. B.

    1987-01-01

    MOLICEL rechargeable lithium cells were cycled in batteries using series, parallel, and series/parallel connections. The individual cell voltages and branch currents were measured to understand the cell interactions. The observations were interpreted in terms of the inherent characteristics of the Li/MoS2 system and in terms of a singular cell failure mode. The results confirm that correctly configured multicell batteries using MOLICELs have performance characteristics comparable to those of single cells.

  10. Evaluation of groundwater artificial recharge management scenario for sustainable water resources development in Gaza Strip

    NASA Astrophysics Data System (ADS)

    Rusteberg, Bernd; Azizur Rahman, M.; Abusaada, Muath; Rabi, Ayman; Rahman Tamimi, A.; Sauter, Martin

    2010-05-01

    The water resources in Gaza Strip are currently facing extreme over-exploitation which has led to a sharp decline of the groundwater level in this Mediterranean coastal aquifer overtime. Salinity of the groundwater is very high as a result of subsequent seawater intrusion of the aquifer. The contamination of the Gaza Strip groundwater by seawater has wide-ranging effects on the regional economy as well as agricultural productivity. In order to guarantee the sustainability of regional development, which requires the access to clean water, groundwater artificial recharge (AR) is being considered as a potential solution to this current water resources problem. The objective of the present study is to analyze several strategies for the implementation and management of AR in Gaza Strip and their potential impacts on agriculture, environment, and the socio-economy. Based on the water policy on wastewater reclamation and reuse (Yr. 2005 - 2025), six AR management strategies were developed in close cooperation with the local stakeholder community. These scenarios take into consideration the development of the new North Gaza Wastewater Treatment Plant and were also judged with respect to a base-line scenario, otherwise known as the "Do Nothing Approach." Multi-Criteria Decision Analysis (MCDA) on ranking of the AR management scenarios was used. Twenty-one criteria ranging over a wide spectrum and four categories (Environmental, Public Health, Social, and Economical) were defined to ensure sound evaluation of each of the six AR management scenarios. A detailed geo-database was prepared to analyze all the related spatial, non-spatial, and temporal data. Socio-economic studies, field surveys, mathematical modeling, and GIS analysis were used for the criteria quantification. In the MCDA, Analytical Hierarchy Method (AHP) combined with weighted Linear Combination (WLC) and Composite Programming (CP) was employed. The six AR management strategies were thus compared to the "Do Nothing Approach" based on the defined environmental, health, social, and economical criteria, the most important being related to the environment and the economy. The robustness of the achieved ranking of AR management options has been tested by changing the selected criteria, criteria importance and criteria structure. The final analysis shows that all six AR management strategies are better than "doing nothing". The implementation of groundwater artificial recharge with maximum possible infiltration of secondary treated effluent in conjunction with sustainable reuse of the recharged water for agricultural development is the most effective AR solution to the water resources problems of the Gaza Strip.

  11. Ground-Water Recharge from Small Intermittent Streams in the Western Mojave Desert, California

    USGS Publications Warehouse

    Izbicki, John A.; Johnson, Russell U.; Kulongoski, Justin T.; Predmore, Steven

    2007-01-01

    Population growth has impacted ground-water resources in the western Mojave Desert, where declining water levels suggest that recharge rates have not kept pace with withdrawals. Recharge from the Mojave River, the largest hydrographic feature in the study area, is relatively well characterized. In contrast, recharge from numerous smaller streams that convey runoff from the bounding mountains is poorly characterized. The current study examined four representative streams to assess recharge from these intermittent sources. Hydraulic, thermal, geomorphic, chemical, and isotopic data were used to study recharge processes, from streamflow generation and infiltration to percolation through the unsaturated zone. Ground-water movement away from recharge areas was also assessed. Infiltration in amounts sufficient to have a measurable effect on subsurface temperature profiles did not occur in every year in instrumented study reaches. In addition to streamflow availability, results showed the importance of sediment texture in controlling infiltration and eventual recharge. Infiltration amounts of about 0.7 meters per year were an approximate threshold for the occurrence of ground-water recharge. Estimated travel times through the thick unsaturated zones underlying channels reached several hundred years. Recharging fluxes were influenced by stratigraphic complexity and depositional dynamics. Because of channel meandering, not all water that penetrates beneath the root zone can be assumed to become recharge on active alluvial fans. Away from study washes, elevated chloride concentrations and highly negative water potentials beneath the root zone indicated negligible recharge from direct infiltration of precipitation under current climatic conditions. In upstream portions of washes, generally low subsurface chloride concentrations and near-zero water potentials indicated downward movement of water toward the water table, driven primarily by gravity. Recharging conditions did not extend to the distal ends of all washes. Where urbanization had concentrated spatially distributed runoff into a small number of fixed channels, enhanced infiltration induced recharging conditions, mobilizing accumulated chloride. Estimated amounts of ground-water recharge from the studied reaches were small. Extrapolating on the basis of drainage areas, the estimated aggregate recharge from small intermittent streams is minor compared to recharge from the Mojave River. Recharge is largely controlled by streamflow availability, which primarily reflects precipitation patterns. Precipitation in the Mojave Desert is strongly controlled by topography. Cool moist air masses from the Pacific Ocean are mostly blocked from entering the desert by the high mountains bordering its southern edge. Storms do, however, readily enter the region through Cajon Pass. These storms generate flow in the Mojave River that often reaches Afton Canyon, more than 150 kilometers downstream. The isotopic composition of ground water reflects the localization of recharge beneath the Mojave River. Similar processes occur near San Gorgonio Pass, 75 kilometers southeast from Cajon Pass along the bounding San Andreas Fault.

  12. Evaluating storm-scale groundwater recharge dynamics with coupled weather radar data and unsaturated zone modeling

    NASA Astrophysics Data System (ADS)

    Nasta, P.; Gates, J. B.; Lock, N.; Houston, A. L.

    2013-12-01

    Groundwater recharge rates through the unsaturated zone emerge from complex interactions within the soil-vegetation-atmosphere system that derive from nonlinear relationships amongst atmospheric boundary conditions, plant water use and soil hydraulic properties. While it is widely recognized that hydrologic models must capture soil water dynamics in order to provide reliable recharge estimates, information on episodic recharge generation remains uncommon, and links between storm-scale weather patterns and their influence on recharge is largely unexplored. In this study, the water balance of a heterogeneous one-dimensional soil domain (3 m deep) beneath a typical rainfed corn agro-ecosystem in eastern Nebraska was numerically simulated in HYDRUS-1D for 12 years (2001-2012) on hourly time steps in order to assess the relationships between weather events and episodic recharge generation. WSR-88D weather radar reflectivity data provided both rainfall forcing data (after estimating rain rates using the z/r ratio method) and a means of storm classification on a scale from convective to stratiform using storm boundary characteristics. Individual storm event importance to cumulative recharge generation was assessed through iterative scenario modeling (773 total simulations). Annual cumulative recharge had a mean value of 9.19 cm/yr (about 12 % of cumulative rainfall) with coefficient of variation of 73%. Simulated recharge generation events occurred only in late winter and spring, with a peak in May (about 35% of total annual recharge). Recharge generation is observed primarily in late spring and early summer because of the combination of high residual soil moisture following a winter replenishment period, heavy convective storms, and low to moderate potential evapotranspiration rates. During the growing season, high rates of root water uptake cause rapid soil water depletion, and the concurrent high potential evapotranspiration and low soil moisture prevented recharge generation until late winter, even when intense convective storms took place. For this reason, about 86% of all precipitation events produce insignificant recharge contributions. Recharge responses to individual storms were nonlinear and did not cluster well with either storm amount or storm classification type. For example, ~7% of rainfall events fall near the 1:1 rainfall/recharge line and these events represent about 37% of cumulative recharge, and individual storms accounted for up to 4% of their annual totals. However, recharge events in late winter are mainly triggered by stratiform precipitation whereas in spring they are generally generated by convective storms. This novel approach to assessing storm-scale recharge may be relevant to several current challenges in the characterization of groundwater recharge processes, including the evaluation of their spatiotemporal distributions and the impacts of climate change on groundwater.

  13. Movement of water infiltrated from a recharge basin to wells.

    PubMed

    O'Leary, David R; Izbicki, John A; Moran, Jean E; Meeth, Tanya; Nakagawa, Brandon; Metzger, Loren; Bonds, Chris; Singleton, Michael J

    2012-01-01

    Local surface water and stormflow were infiltrated intermittently from a 40-ha basin between September 2003 and September 2007 to determine the feasibility of recharging alluvial aquifers pumped for public supply, near Stockton, California. Infiltration of water produced a pressure response that propagated through unconsolidated alluvial-fan deposits to 125 m below land surface (bls) in 5 d and through deeper, more consolidated alluvial deposits to 194 m bls in 25 d, resulting in increased water levels in nearby monitoring wells. The top of the saturated zone near the basin fluctuates seasonally from depths of about 15 to 20 m. Since the start of recharge, water infiltrated from the basin has reached depths as great as 165 m bls. On the basis of sulfur hexafluoride tracer test data, basin water moved downward through the saturated alluvial deposits until reaching more permeable zones about 110 m bls. Once reaching these permeable zones, water moved rapidly to nearby pumping wells at rates as high as 13 m/d. Flow to wells through highly permeable material was confirmed on the basis of flowmeter logging, and simulated numerically using a two-dimensional radial groundwater flow model. Arsenic concentrations increased slightly as a result of recharge from 2 to 6 µg/L immediately below the basin. Although few water-quality issues were identified during sample collection, high groundwater velocities and short travel times to nearby wells may have implications for groundwater management at this and at other sites in heterogeneous alluvial aquifers. PMID:21740423

  14. Rechargeable Room-Temperature Na-CO2 Batteries.

    PubMed

    Hu, Xiaofei; Sun, Jianchao; Li, Zifan; Zhao, Qing; Chen, Chengcheng; Chen, Jun

    2016-05-23

    Developing rechargeable Na-CO2 batteries is significant for energy conversion and utilization of CO2 . However, the reported batteries in pure CO2 atmosphere are non-rechargeable with limited discharge capacity of 200 mAh g(-1) . Herein, we realized the rechargeability of a Na-CO2 battery, with the proposed and demonstrated reversible reaction of 3 CO2 +4 Na↔2 Na2 CO3 +C. The battery consists of a Na anode, an ether-based electrolyte, and a designed cathode with electrolyte-treated multi-wall carbon nanotubes, and shows reversible capacity of 60000 mAh g(-1) at 1 A g(-1) (≈1000 Wh kg(-1) ) and runs for 200 cycles with controlled capacity of 2000 mAh g(-1) at charge voltage <3.7 V. The porous structure, high electro-conductivity, and good wettability of electrolyte to cathode lead to reduced electrochemical polarization of the battery and further result in high performance. Our work provides an alternative approach towards clean recycling and utilization of CO2 . PMID:27089434

  15. Trace organic chemicals contamination in ground water recharge.

    PubMed

    Díaz-Cruz, M Silvia; Barceló, Damià

    2008-06-01

    Population growth and unpredictable climate changes will pose high demands on water resources in the future. Even at present, surface water is certainly not enough to cope with the water requirement for agricultural, industrial, recreational and drinking purposes. In this context, the usage of ground water has become essential, therefore, their quality and quantity has to be carefully managed. Regarding quantity, artificial recharge can guarantee a sustainable level of ground water, whilst the strict quality control of the waters intended for recharge will minimize contamination of both the ground water and aquifer area. However, all water resources in the planet are threatened by multiple sources of contamination coming from the extended use of chemicals worldwide. In this respect, the environmental occurrence of organic micropollutants such as pesticides, pharmaceuticals, industrial chemicals and their metabolites has experienced fast growing interest. In this paper an overview of the priority and emerging organic micropollutants in the different source waters used for artificial aquifer recharge purposes and in the recovered water is presented. Besides, some considerations regarding fate and removal of such compounds are also addressed. PMID:18378277

  16. Natural recharge and localization of fresh ground water in Kuwait

    USGS Publications Warehouse

    Bergstrom, R.E.; Aten, R.E.

    1965-01-01

    Fresh ground water (200 parts per million total dissolved solids and upwards) occurs in portions of Pleistocene sandstone aquifers beneath basins and wadis in north Kuwait where the mean rainfall is about five inches per year. The fresh water is surrounded and underlain by brackish water (> 4000 ppm TDS). Drilling and testing show that fresh water saturation is restricted to wadis and basin areas; in Rawdatain basin it attains a maximum thickness of about 110 feet and a lateral extent of about seven miles. The fresh ground water represents recharge localized, during infrequent, torrential rain storms, in areas of concentrated runoff where sediments in the vadose zone are moderately permeable and depth to the water table is generally less than a hundred feet. Concentration of runoff appears to be the primary control in the localization of recharge. The fresh water percolates downward to the ground-water reservoir following rare storms, then flows in the direction of hydraulic gradient and gradually becomes brackish. Theoretical delineation of the recharge area and ground-water flow pattern in Rawdatain was confirmed by tritium and C14 dating of the water. Brackish ground-water conditions prevail from water table downward in areas where rainfall infiltrates essentially where it falls, permeability of sediments in the vadose zone is low, or the water table is several hundred feet below land surface. In these areas, rainfall is retained and lost within the soil zone or becomes mineralized during deep percolation. ?? 1964.

  17. Identification of priority organic compounds in groundwater recharge of China.

    PubMed

    Li, Zhen; Li, Miao; Liu, Xiang; Ma, Yeping; Wu, Miaomiao

    2014-09-15

    Groundwater recharge using reclaimed water is considered a promising method to alleviate groundwater depletion, especially in arid areas. Traditional water treatment systems are inefficient to remove all the types of contaminants that would pose risks to groundwater, so it is crucial to establish a priority list of organic compounds (OCs) that deserve the preferential treatment. In this study, a comprehensive ranking system was developed to determine the list and then applied to China. 151 OCs, for which occurrence data in the wastewater treatment plants were available, were selected as candidate OCs. Based on their occurrence, exposure potential and ecological effects, two different rankings of OCs were established respectively for groundwater recharge by surface infiltration and direct aquifer injection. Thirty-four OCs were regarded as having no risks while the remaining 117 OCs were divided into three groups: high, moderate and low priority OCs. Regardless of the recharge way, nonylphenol, erythromycin and ibuprofen were the highest priority OCs; their removal should be prioritized. Also the database should be updated as detecting technology is developed. PMID:24960229

  18. Wastewater reclamation and recharge: A water management strategy for Albuquerque

    SciTech Connect

    Gorder, P.J.; Brunswick, R.J.; Bockemeier, S.W.

    1995-12-31

    Approximately 61,000 acre-feet of the pumped water is annually discharged to the Rio Grande as treated wastewater. Albuquerque`s Southside Water Reclamation Plant (SWRP) is the primary wastewater treatment facility for most of the Albuquerque area. Its current design capacity is 76 million gallons per day (mgd), which is expected to be adequate until about 2004. A master plan currently is being prepared (discussed here in Wastewater Master Planning and the Zero Discharge Concept section) to provide guidelines for future expansions of the plant and wastewater infrastructure. Construction documents presently are being prepared to add ammonia and nitrogen removal capability to the plant, as required by its new discharge permit. The paper discusses water management strategies, indirect potable reuse for Albuquerque, water quality considerations for indirect potable reuse, treatment for potable reuse, geohydrological aspects of a recharge program, layout and estimated costs for a conceptual reclamation and recharge system, and work to be accomplished under phase 2 of the reclamation and recharge program.

  19. Investigation of recharge dynamics and flow paths in a fractured crystalline aquifer in semi-arid India using borehole logs: implications for managed aquifer recharge

    NASA Astrophysics Data System (ADS)

    Alazard, M.; Boisson, A.; Maréchal, J.-C.; Perrin, J.; Dewandel, B.; Schwarz, T.; Pettenati, M.; Picot-Colbeaux, G.; Kloppman, W.; Ahmed, S.

    2016-02-01

    The recharge flow paths in a typical weathered hard-rock aquifer in a semi-arid area of southern India were investigated in relation to structures associated with a managed aquifer recharge (MAR) scheme. Despite the large number of MAR structures, the mechanisms of recharge in their vicinity are still unclear. The study uses a percolation tank as a tool to identify the input signal of the recharge and uses multiple measurements (piezometric time series, electrical conductivity profiles in boreholes) compared against heat-pulse flowmeter measurements and geochemical data (major ions and stable isotopes) to examine recharge flow paths. The recharge process is a combination of diffuse piston flow and preferential flow paths. Direct vertical percolation appears to be very limited, in contradiction to the conceptual model generally admitted where vertical flow through saprolite is considered as the main recharge process. The horizontal component of the flow leads to a strong geochemical stratification of the water column. The complex recharge pattern, presented in a conceptual model, leads to varied impacts on groundwater quality and availability in both time and space, inducing strong implications for water management, water quality evolution, MAR monitoring and longer-term socio-economic costs.

  20. Recharged or modified-connate water in a carbonate bed within an evaporite aquitard, Texas panhandle

    SciTech Connect

    Dutton, A.R.; Kreitler, C.W.

    1985-01-01

    Hydraulic-head data and numerical modeling suggest that ground water in the Palo Duro Basin area of the Texas Panhandle has leaked downward through a Permian evaporite-carbonate-shale aquitard. Chemical composition of brine in a carbonate bed of the San Andres Formation within the aquitard gives ambiguous evidence of ground-water leakage. San Andres ground water varies chemically from potable Ca-HCO/sub 3/- and Ca-SO/sub 4/-type waters in the nonhalitic sections of the San Andres Formation below the Pecos Plains of eastern New Mexico to Na-Ca-Cl brine within the Palo Duro Basin. The composition of the 336 to 384 g/L brine can be explained by solution of dolomite, anhydrite, and halite, accompanied by exchange of some sodium for calcium. The brine is near oxygen isotopic equilibrium with San Andres dolomite. Problems with this recharged-water explanation are identification of the water-rock reaction that replaces dissolved sodium with calcium and the reaction that enriches deltaD of San Andres brine by 30 per thousand to 40 per thousand relative to modern regional meteoric water. Problems with explaining San Andres brine as modified-connate water are that hydraulic-head data and numerical modeling suggest leakage occurs and that ion ratios in brine differ from ion ratios in evaporatively concentrated, diagenetically modified seawater. However, because leakage rates are slow and variable, some modified-connate brine could be mixed with leaking recharged water, making interpretation difficult. Leakage rate and extent of flushing of old brine depend on whether flow is through fractures or through intergranular pore space in the evaporite aquitard.

  1. Comparative analysis of selected fuel cell vehicles

    SciTech Connect

    1993-05-07

    Vehicles powered by fuel cells operate more efficiently, more quietly, and more cleanly than internal combustion engines (ICEs). Furthermore, methanol-fueled fuel cell vehicles (FCVs) can utilize major elements of the existing fueling infrastructure of present-day liquid-fueled ICE vehicles (ICEVs). DOE has maintained an active program to stimulate the development and demonstration o fuel cell technologies in conjunction with rechargeable batteries in road vehicles. The purpose of this study is to identify and assess the availability of data on FCVs, and to develop a vehicle subsystem structure that can be used to compare both FCVs and ICEV, from a number of perspectives--environmental impacts, energy utilization, materials usage, and life cycle costs. This report focuses on methanol-fueled FCVs fueled by gasoline, methanol, and diesel fuel that are likely to be demonstratable by the year 2000. The comparative analysis presented covers four vehicles--two passenger vehicles and two urban transit buses. The passenger vehicles include an ICEV using either gasoline or methanol and an FCV using methanol. The FCV uses a Proton Exchange Membrane (PEM) fuel cell, an on-board methanol reformer, mid-term batteries, and an AC motor. The transit bus ICEV was evaluated for both diesel and methanol fuels. The transit bus FCV runs on methanol and uses a Phosphoric Acid Fuel Cell (PAFC) fuel cell, near-term batteries, a DC motor, and an on-board methanol reformer. 75 refs.

  2. Comparing the Energy Content of Batteries, Fuels, and Materials

    ERIC Educational Resources Information Center

    Balsara, Nitash P.; Newman, John

    2013-01-01

    A methodology for calculating the theoretical and practical specific energies of rechargeable batteries, fuels, and materials is presented. The methodology enables comparison of the energy content of diverse systems such as the lithium-ion battery, hydrocarbons, and ammonia. The methodology is relevant for evaluating the possibility of using

  3. Comparing the Energy Content of Batteries, Fuels, and Materials

    ERIC Educational Resources Information Center

    Balsara, Nitash P.; Newman, John

    2013-01-01

    A methodology for calculating the theoretical and practical specific energies of rechargeable batteries, fuels, and materials is presented. The methodology enables comparison of the energy content of diverse systems such as the lithium-ion battery, hydrocarbons, and ammonia. The methodology is relevant for evaluating the possibility of using…

  4. Overview of Ground-Water Recharge Study Sites

    USGS Publications Warehouse

    Constantz, Jim; Adams, Kelsey S.; Stonestrom, David A.

    2007-01-01

    Multiyear studies were done to examine meteorologic and hydrogeologic controls on ephemeral streamflow and focused ground-water recharge at eight sites across the arid and semiarid southwestern United States. Campaigns of intensive data collection were conducted in the Great Basin, Mojave Desert, Sonoran Desert, Rio Grande Rift, and Colorado Plateau physiographic areas. During the study period (1997 to 2002), the southwestern region went from wetter than normal conditions associated with a strong El Ni?o climatic pattern (1997?1998) to drier than normal conditions associated with a La Ni?a climatic pattern marked by unprecedented warmth in the western tropical Pacific and Indian Oceans (1998?2002). The strong El Ni?o conditions roughly doubled precipitation at the Great Basin, Mojave Desert, and Colorado Plateau study sites. Precipitation at all sites trended generally lower, producing moderate- to severe-drought conditions by the end of the study. Streamflow in regional rivers indicated diminishing ground-water recharge conditions, with annual-flow volumes declining to 10?46 percent of their respective long-term averages by 2002. Local streamflows showed higher variability, reflecting smaller scales of integration (in time and space) of the study-site watersheds. By the end of the study, extended periods (9?15 months) of zero or negligible flow were observed at half the sites. Summer monsoonal rains generated the majority of streamflow and associated recharge in the Sonoran Desert sites and the more southerly Rio Grande Rift site, whereas winter storms and spring snowmelt dominated the northern and westernmost sites. Proximity to moisture sources (primarily the Pacific Ocean and Gulf of California) and meteorologic fluctuations, in concert with orography, largely control the generation of focused ground-water recharge from ephemeral streamflow, although other factors (geology, soil, and vegetation) also are important. Watershed area correlated weakly with focused infiltration volumes, the latter providing an upper bound on associated ground-water recharge. Estimates of annual focused infiltration for the research sites ranged from about 105 to 107 cubic meters from contributing areas that ranged from 26 to 2,260 square kilometers.

  5. Aquifer recharge with reclaimed water in the Llobregat Delta. Laboratory batch experiments and field test site.

    NASA Astrophysics Data System (ADS)

    Tobella, J.

    2010-05-01

    Summary Spain, as most other Mediterranean countries, faces near future water shortages, generalized pollution and loss of water dependent ecosystems. Aquifer recharge represents a promising option to become a source for indirect potable reuse purposes but presence of pathogens as well as organic and inorganic pollutants should be avoided. To this end, understanding the processes of biogeochemical degradation occurring within the aquifer during infiltration is capital. A set of laboratory batch experiments has been assembled in order to assess the behaviour of selected pesticides, drugs, estrogens, surfactant degradation products, biocides and phthalates under different redox conditions. Data collected during laboratory experiments and monitoring activities at the Sant Vicenç dels Horts test site will be used to build and calibrate a numerical model (i) of the physical-chemical-biochemical processes occurring in the batches and (ii) of multicomponent reactive transport in the unsaturated/saturated zone at the test site. Keywords Aquifer recharge, batch experiments, emerging micropollutants, infiltration, numerical model, reclaimed water, redox conditions, Soil Aquifer Treatment (SAT). 1. Introduction In Spain, the Llobregat River and aquifers, which supply water to Barcelona, have been overexploited for years and therefore, suffer from serious damages: the river dries up on summer, riparian vegetation has disappeared and seawater has intruded the aquifer. In a global context, solutions to water stress problems are urgently needed yet must be sustainable, economical and safe. Recent developments of analytical techniques detect the presence of the so-called "emerging" organic micropollutants in water and soils. Such compounds may affect living organisms when occurring in the environment at very low concentrations (microg/l or ng/l). In wastewater and drinking water treatment plants, a remarkable removal of these chemicals from water can be obtained only using advanced and costly treatments. Nevertheless, a number of studies are demonstrating that physical, chemical and biochemical processes associated with water movement within the subsoil represent a natural alternative way to reduce the presence of these contaminants. This processes are called Soil Aquifer Treatment (SAT). Aquifer recharge will become a source for indirect potable reuse purposes as long as the presence of pathogens and organic and inorganic pollutants is avoided. To this end, understanding the biogeochemical degradation processes occurring within the aquifer during infiltration is capital. 2. Laboratory batch experiments A set of laboratory batch experiments has been assembled to assess the behaviour of selected pesticides, drugs, estrogens, surfactant degradation products, biocides and phthalates under different redox conditions. The setup of the experiments consists of glass bottles containing 120 g of soil and 240 ml of synthetic water spiked with the mix of micropollutants. A source of easily degradable organic carbon and, depending on the type of test, electron acceptors are added in order to yield aerobic respiration and nitrate/iron/manganese/sulphate reduction conditions. The evolution of the processes is monitored by sacrificing duplicate bottles according to a defined schedule and analysing water for major and minor components as well as for micropollutants. Results from biotic tests are compared with abiotic ones in order to discern biodegradation from other chemical processes. The soil, the synthetic water and the micropollutants selected for the experiments are representative of a test site in the nearby of Barcelona (Spain) where artificial recharge of groundwater through ponds is going to be performed using river water or tertiary effluent from a waste water treatment plant. The results of the experiments improve the knowledge on the behaviour of the selected micropollutants under different redox conditions and provide with useful information on the conditions to develop at the test site during artificial recharge. The data collected during the laboratory experiments and in the test site will be used to build and calibrate a numerical model of the physical-chemical-biochemical processes developing in the batches and of multicomponent reactive transport in the unsaturated/saturated zone in the test site area. 3. Field test site The infiltration site of Sant Vicenç dels Horts has been selected to assessing the biogeochemical processes occurring during SAT. The system consists of two ponds that have been built as compensatory measure for the reduction in natural recharge caused by the construction of the High Speed Train Line. The first pond acts as a decantation pond while the second one acts as an infiltration basin (Figure 1). Recharge water comes from the tertiary treatment plant of the El Prat de Llobregat WWTP and the river (?). The CUADLL (Lower Llobregat Aquifer End-Users Community) is now managing the system operation. Tasks that are currently being carried out at this Test Site aims at (i) improving the local experience on MAR through infiltration ponds operational aspects and (ii) monitoring the changes in water quality during the recharge processes (unsaturated and saturated zone). Special attention is being paid to the fate of emerging organic pollutants (pharmaceuticals, surfactants, pesticides, etc.). The yielding of the monitoring will be compared with the results from the laboratory batch experiments on the behaviour of selected emerging organic pollutants. To this end, observation wells have been constructed, pressure / temperature / electrical conductivity transducers have been installed and the vadose zone under the infiltration pond has been instrumented (tensiometers, water content probes and suction cups). In addition double ring and infiltration tests have been performed in order to forecast the infiltration capacity of the basin.

  6. Implications of projected climate change for groundwater recharge in the western United States

    NASA Astrophysics Data System (ADS)

    Meixner, Thomas; Manning, Andrew H.; Stonestrom, David A.; Allen, Diana M.; Ajami, Hoori; Blasch, Kyle W.; Brookfield, Andrea E.; Castro, Christopher L.; Clark, Jordan F.; Gochis, David J.; Flint, Alan L.; Neff, Kirstin L.; Niraula, Rewati; Rodell, Matthew; Scanlon, Bridget R.; Singha, Kamini; Walvoord, Michelle A.

    2016-03-01

    Existing studies on the impacts of climate change on groundwater recharge are either global or basin/location-specific. The global studies lack the specificity to inform decision making, while the local studies do little to clarify potential changes over large regions (major river basins, states, or groups of states), a scale often important in the development of water policy. An analysis of the potential impact of climate change on groundwater recharge across the western United States (west of 100° longitude) is presented synthesizing existing studies and applying current knowledge of recharge processes and amounts. Eight representative aquifers located across the region were evaluated. For each aquifer published recharge budget components were converted into four standard recharge mechanisms: diffuse, focused, irrigation, and mountain-systems recharge. Future changes in individual recharge mechanisms and total recharge were then estimated for each aquifer. Model-based studies of projected climate-change effects on recharge were available and utilized for half of the aquifers. For the remainder, forecasted changes in temperature and precipitation were logically propagated through each recharge mechanism producing qualitative estimates of direction of changes in recharge only (not magnitude). Several key patterns emerge from the analysis. First, the available estimates indicate average declines of 10-20% in total recharge across the southern aquifers, but with a wide range of uncertainty that includes no change. Second, the northern set of aquifers will likely incur little change to slight increases in total recharge. Third, mountain system recharge is expected to decline across much of the region due to decreased snowpack, with that impact lessening with higher elevation and latitude. Factors contributing the greatest uncertainty in the estimates include: (1) limited studies quantitatively coupling climate projections to recharge estimation methods using detailed, process-based numerical models; (2) a generally poor understanding of hydrologic flowpaths and processes in mountain systems; (3) difficulty predicting the response of focused recharge to potential changes in the frequency and intensity of extreme precipitation events; and (4) unconstrained feedbacks between climate, irrigation practices, and recharge in highly developed aquifer systems.

  7. Simulated artificial recharge in the Big Sioux Aquifer in Minnehaha County, South Dakota

    USGS Publications Warehouse

    Koch, N.C.

    1984-01-01

    The Big Sioux aquifer in Minnehaha County is a water-table aquifer hydraulically connected to the Big Sioux River. A digital-computer model previously developed by the U.S. Geological Survey was used to simulate potential effects of artificial recharge on the aquifer. A simulation was made by recharging water at the rate of 870 gallons per minute for four 30-day periods. Total water recharged to the aquifer during the 120 days was 150.3 million gallons. About 24.4 million gallons of water discharged from the aquifer to the river during the 120-day recharge period and about 30 million gallons discharged from the aquifer to the river during three 30-day recovery periods, both as a result of the artificial recharge, therefore, a total of 54.4 million gallons or 36 percent of the 150.3 million gallons that was artificially recharged from the aquifer to the river. (USGS)

  8. Estimating harvested rainwater at greenhouses in south Portugal aquifer Campina de Faro for potential infiltration in Managed Aquifer Recharge.

    NASA Astrophysics Data System (ADS)

    Costa, Luís; Monteiro, José Paulo; Leitão, Teresa; Lobo-Ferreira, João Paulo; Oliveira, Manuel; Martins de Carvalho, José; Martins de Carvalho, Tiago; Agostinho, Rui

    2015-04-01

    The Campina de Faro (CF) aquifer system, located on the south coast of Portugal, is an important source of groundwater, mostly used for agriculture purposes. In some areas, this multi-layered aquifer is contaminated with high concentration of nitrates, possibly arising from excessive usage of fertilizers, reaching to values as high as 300 mg/L. In order to tackle this problem, Managed Aquifer Recharge (MAR) techniques are being applied at demonstration scale to improve groundwater quality through aquifer recharge, in both infiltration basins at the river bed of ephemeral river Rio Seco and existing traditional large diameter wells located in this aquifer. In order to assess the infiltration capacity of the existing infrastructures, in particular infiltration basins and large diameter wells at CF aquifer, infiltration tests were performed, indicating a high infiltration capacity of the existing infrastructures. Concerning the sources of water for recharge, harvested rainwater at greenhouses was identified in CF aquifer area as one of the main potential sources for aquifer recharge, once there is a large surface area occupied by these infrastructures at the demo site. This potential source of water could, in some cases, be redirected to the large diameter wells or to the infiltration basins at the riverbed of Rio Seco. Estimates of rainwater harvested at greenhouses were calculated based on a 32 year average rainfall model and on the location of the greenhouses and their surface areas, the latter based on aerial photograph. Potential estimated annual rainwater intercepted by greenhouses at CF aquifer accounts an average of 1.63 hm3/year. Nonetheless it is unlikely that the totality of this amount can be harvested, collected and redirected to aquifer recharge infrastructures, for several reasons, such as the lack of appropriate greenhouse infrastructures, conduits or a close location between greenhouses and large diameter wells and infiltration basins. Anyway, this value is a good indication of the total amount of the harvested rainfall that could be considered for future MAR solutions. Given the estimates on the greenhouse harvested rainwater and the infiltration capacity of the infiltration basins and large diameter wells, it is intended to develop groundwater flow models in order to assess the nitrate washing rate in the CF aquifer. This work is being developed under the scope of MARSOL Project (MARSOL-GA-2013-619120), in which Campina de Faro aquifer system is one of the several case studies. This project aims to demonstrate that MAR is a sound, safe and sustainable strategy that can be applied with great confidence in finding solutions to water scarcity in Southern Europe.

  9. Contributing recharge areas, groundwater travel time, and groundwater water quality of the Missouri River alluvial aquifer near the City of Independence, Missouri, well field, 1997-2008

    USGS Publications Warehouse

    Kelly, Brian P.

    2011-01-01

    The City of Independence, Missouri, operates a well field in the Missouri River alluvial aquifer. Contributing recharge areas (CRA) were last determined for the well field in 1996. Since that time, eight supply wells have been installed in the area north of the Missouri River and well pumpage has changed for the older supply wells. The change in pumping has altered groundwater flow and substantially changed the character of the CRA and groundwater travel times to the supply wells. The U.S Geological Survey, in a cooperative study with the City of Independence, Missouri, simulated steady-state groundwater flow for 2007 well pumpage, average annual river stage, and average annual recharge. Particle-tracking analysis was used to determine the CRA for supply wells and monitoring wells, and the travel time from recharge areas to supply wells, recharge areas to monitoring wells, and monitoring wells to supply wells. The simulated CRA for the well field is elongated in the upstream direction and extends to both sides of the Missouri River. Groundwater flow paths and recharge areas estimated for monitoring wells indicate the origin of water to each monitoring well, the travel time of that water from the recharge area, the flow path from the vicinity of each monitoring well to a supply well, and the travel time from the monitoring well to the supply well. Monitoring wells 14a and 14b have the shortest groundwater travel time from their contributing recharge area of 0.30 years and monitoring well 29a has the longest maximum groundwater travel time from its contributing recharge area of 1,701 years. Monitoring well 22a has the shortest groundwater travel time of 0.5 day to supply well 44 and monitoring well 3b has the longest maximum travel time of 31.91 years to supply well 10. Water-quality samples from the Independence groundwater monitoring well network were collected from 1997 to 2008 by USGS personnel during ongoing annual sampling within the 10-year contributing recharge area (CRA) of the Independence well field. Statistical summaries and the spatial and temporal variability of water quality in the Missouri River alluvial aquifer near the Independence well field were characterized from analyses of 598 water samples. Water-quality constituent groups include dissolved oxygen and physical properties, nutrients, major ions and trace elements, wastewater indicator compounds, fuel compounds, and total benzene, toluene, ethylbenzene, and xylene (BTEX), alachlor, and atrazine. The Missouri Secondary Maximum Contaminant Level (SMCL) for iron was exceeded in almost all monitoring wells. The Missouri Maximum Contaminant Level (MCL) for arsenic was exceeded 32 times in samples from monitoring wells. The MCL for barium was exceeded five times in samples from one monitoring well. The SMCL for manganese was exceeded 160 times in samples from all monitoring wells and the combined well-field sample. The most frequently detected wastewater indicator compounds were N,N-diethyl-meta-toluamide (DEET), phenol, caffeine, and metolachlor. The most frequently detected fuel compounds were toluene and benzene. Alachlor was detected in 22 samples and atrazine was detected in 37 samples and the combined well-field sample. The MCL for atrazine was exceeded in one sample from one monitoring well. Samples from monitoring wells with median concentrations of total inorganic nitrogen larger than 1 milligram per liter (mg/L) are located near agricultural land and may indicate that agricultural land practices are the source of nitrogen to groundwater. Largest median values of specific conductance; total inorganic nitrogen; dissolved calcium, magnesium, sodium, iron, arsenic, manganese, bicarbonate, and sulfate and detections of wastewater indicator compounds generally were in water samples from monitoring wells with CRAs that intersect the south bank of the Missouri River. Zones of higher specific conductance were located just upstream from the Independen

  10. The Complex Geochemistry of Magma Bodies Undergoing Open-System Processes: Energy-Constrained Recharge, Assimilation and Fractional Crystallization (EC-RAFC)

    NASA Astrophysics Data System (ADS)

    Bohrson, W. A.; Spera, F. J.

    2001-12-01

    A new version of the energy-constrained simulator tracks the thermal and geochemical evolution of a magma body undergoing the processes of magma recharge, assimilation, and fractional crystallization (EC-RAFC). The conceptual framework is presented in a companion abstract (Spera and Bohrson, this issue). The EC-RAFC model tracks trace element and isotopic trends of a magma body (melt + solids) undergoing fractional crystallization and continuous or episodic magma recharge; assimilation may or may not occur. EC-RAFC yields complex, distinctly non-monotonic element-element and element-isotope trends that are a consequence of the nonlinear, coupled nature of the processes that influence the system. Among the plethora of petrologic problems that can be investigated with this simulator are the geochemical distinctions that arise when a magma body undergoes continuous vs. episodic recharge, the connection between erupted magmas and associated cumulate bodies, the geochemical fingerprints of mafic enclaves that form as a consequence of mafic recharge into a more silicic magma body, and the conditions under which magmatic systems reach chemical "steady-state." All of these have important, well-documented analogues in nature and thus, the ability to predict associated geochemical signatures affords the opportunity to begin to discriminate among the many physiochemical and tectonomagmatic models involving complex magmatic systems. Investigation of the effects of continuous vs. episodic recharge for an initially mafic magma undergoing assimilation and recharge in the lower crust indicates that the resulting geochemical trends for melt and solids are highly sensitive to the style of recharge. Geochemical differences in systems experiencing episodic vs. continuous recharge can be well outside analytical uncertainty, suggesting that EC-RAFC represents a tool that can directly link volcanological and geochemical models of magmatic systems. EC-RAFC also predicts complex geochemical trends among cumulates that form as crystallization products of a magma body and enclaves (chilled recharge magma) that form as recharge magma is injected into a magma body. This window into the composition of solids associated with open-system magma bodies allows assessment of the relationships between, for example, layered mafic intrusions and flood basalts, and mafic enclaves and their intermediate-composition volcanic or plutonic hosts. A commonly postulated scenario regarding magmatic systems that appear to erupt relatively homogeneous composition magmas over time involves magma recharge as the agent to maintain this geochemical "steady-state." The EC-RAFC simulator allows specific scenarios to be investigated that can be used to assess the conditions that lead to geochemical homogeneity. Preliminary results indicate that very specific combinations of bulk Ds and element concentrations are required to achieve compositional "steady state" during an RAFC or RFC event. In summary, EC-RAFC provides a method to quantitatively investigate complex magmatic systems in a thermodynamic context; it predicts complex, non-monotonic geochemical trends for which there are analogues in nature and that previously have been difficult to model; and finally, EC-RAFC establishes an essential link between the chemical and physical dimensions of a magmatic system.

  11. Multi-component transport and transformation in deep confined aquifer during groundwater artificial recharge.

    PubMed

    Zhang, Wenjing; Huan, Ying; Yu, Xipeng; Liu, Dan; Zhou, Jingjing

    2015-04-01

    Taking an artificial groundwater recharge site in Shanghai, China as an example, this study employed a combination of laboratory experiment and numerical modeling to investigate the transport and transformation of major solutes, as well as the mechanism of associated water-rock interactions in groundwater during artificial groundwater recharge. The results revealed that: (1) Major ions in groundwater were mainly affected by mixing, ion exchanging (Ca(2+), Mg(2+), Na(+), K(+)), as well as dissolution of Calcite, Dolomite. Dissolution of carbonate minerals was not entirely dependent on the pattern of groundwater recharge, the reactivity of the source water itself as indicated by the sub-saturation with respect to the carbonate minerals is the primary factor. (2) Elemental dissolution of As, Cr and Fe occurred in aquifer was due to the transformation of subsurface environment from anaerobic to aerobic systems. Different to bank filtration recharge or pond recharge, the concentration of Fe near the recharge point was mainly controlled by oxidation dissolution of Siderite, which was followed by a release of As, Cr into groundwater. (3) Field modeling results revealed that the hydro chemical type of groundwater gradually changed from the initial Cl-HCO3-Na type to the Cl-HCO3-Na-Ca type during the recharge process, and its impact radius would reach roughly 800 m in one year. It indicated that the recharge pressure (approx. 0.45 Mpa) would enlarge the impact radius under deep well recharge conditions. According to different recharge modes, longer groundwater resident time will associate with minerals' fully reactions. Although the concentrations of major ions were changing during the artificial recharge process, it did not pose a negative impact on the environmental quality of groundwater. The result of trace elements indicated that controlling the environment factors (especially Eh, DO, flow rate) during the recharge was effective to reduce the potential threats to groundwater quality. PMID:25617875

  12. Soil Water Balance and Recharge Monitoring at the Hanford Site - FY09 Status Report

    SciTech Connect

    Rockhold, Mark L.; Saunders, Danielle L.; Strickland, Christopher E.; Waichler, Scott R.; Clayton, Ray E.

    2009-09-28

    Recharge provides the primary driving force for transporting contaminants from the vadose zone to underlying aquifer systems. Quantification of recharge rates is important for assessing contaminant transport and fate and for evaluating remediation alternatives. This report describes the status of soil water balance and recharge monitoring performed by Pacific Northwest National Laboratory at the Hanford Site for Fiscal Year 2009. Previously reported data for Fiscal Years 2004 - 2008 are updated with data collected in Fiscal Year 2009 and summarized.

  13. Using noble gas tracers to constrain a groundwater flow model with recharge elevations: A novel approach for mountainous terrain

    NASA Astrophysics Data System (ADS)

    Doyle, Jessica M.; Gleeson, Tom; Manning, Andrew H.; Mayer, K. Ulrich

    2015-10-01

    Environmental tracers provide information on groundwater age, recharge conditions, and flow processes which can be helpful for evaluating groundwater sustainability and vulnerability. Dissolved noble gas data have proven particularly useful in mountainous terrain because they can be used to determine recharge elevation. However, tracer-derived recharge elevations have not been utilized as calibration targets for numerical groundwater flow models. Herein, we constrain and calibrate a regional groundwater flow model with noble-gas-derived recharge elevations for the first time. Tritium and noble gas tracer results improved the site conceptual model by identifying a previously uncertain contribution of mountain block recharge from the Coast Mountains to an alluvial coastal aquifer in humid southwestern British Columbia. The revised conceptual model was integrated into a three-dimensional numerical groundwater flow model and calibrated to hydraulic head data in addition to recharge elevations estimated from noble gas recharge temperatures. Recharge elevations proved to be imperative for constraining hydraulic conductivity, recharge location, and bedrock geometry, and thus minimizing model nonuniqueness. Results indicate that 45% of recharge to the aquifer is mountain block recharge. A similar match between measured and modeled heads was achieved in a second numerical model that excludes the mountain block (no mountain block recharge), demonstrating that hydraulic head data alone are incapable of quantifying mountain block recharge. This result has significant implications for understanding and managing source water protection in recharge areas, potential effects of climate change, the overall water budget, and ultimately ensuring groundwater sustainability.

  14. Estimated ground-water recharge from streamflow in Fortymile Wash near Yucca Mountain, Nevada

    SciTech Connect

    Savard, C.S.

    1998-10-01

    The two purposes of this report are to qualitatively document ground-water recharge from stream-flow in Fortymile Wash during the period 1969--95 from previously unpublished ground-water levels in boreholes in Fortymile Canyon during 1982--91 and 1995, and to quantitatively estimate the long-term ground-water recharge rate from streamflow in Fortymile Wash for four reaches of Fortymile Wash (Fortymile Canyon, upper Jackass Flats, lower Jackass Flats, and Amargosa Desert). The long-term groundwater recharge rate was estimated from estimates of the volume of water available for infiltration, the volume of infiltration losses from streamflow, the ground-water recharge volume from infiltration losses, and an analysis of the different periods of data availability. The volume of water available for infiltration and ground-water recharge in the four reaches was estimated from known streamflow in ephemeral Fortymile Wash, which was measured at several gaging station locations. The volume of infiltration losses from streamflow for the four reaches was estimated from a streamflow volume loss factor applied to the estimated streamflows. the ground-water recharge volume was estimated from a linear relation between infiltration loss volume and ground-water recharge volume for each of the four reaches. Ground-water recharge rates were estimated for three different periods of data availability (1969--95, 1983--95, and 1992--95) and a long-term ground-water recharge rate estimated for each of the four reaches.

  15. Artificial-recharge investigation near Aurora, Nebraska: 2-year progress report

    USGS Publications Warehouse

    Lichtler, William F.; Stannard, David I.; Kouma, Edwin

    1979-01-01

    This report presents the results of the first 2 years of a 4-year investigation of potential for artificial recharge and recharge methods that might be used to mitigate excessive aquifer depletion in Nebraska. A Quaternary sand-and-gravel aquifer near Aurora, Nebr., was recharged by injecting water through a well at a rate of approximately 730 gallons per minute for nearly 6 months. Total recharge was 530 acre-feet. Recharge was intermittent during the first 2 months, but was virtually continuous during the last 4 months. Buildup of the water level in the recharge well was 17 feet. The rate of buildup indicates that the well could have accepted water by gravity flow at more than 3,000 gallons per minute for at least 1 year. The cause of a continuing slow rise in water levels in the recharge well in contrast to nearly stable water levels in observation wells as close as 10 feet from the recharge well is as yet uncertain. The recharge water and the native ground water appeared to be chemically compatible. Infiltration rates from 24-foot-diameter surface impoundments ranged from 0.04 to 0.66 feet per day. The higher rates may have resulted in part from leakage down incompletely sealed holes that were drilled to install monitoring equipment. The investigation, including a report on the entire project, is scheduled for completion by 1980.

  16. Potential for, and possible effects of, artificial recharge in Carson Valley, Douglas County, Nevada

    USGS Publications Warehouse

    Maurer, Douglas K.; Peltz, Lorri A.

    1994-01-01

    Rapid population growth in Carson Valley, west- central Nevada, requires a dependable municipal water source. Artificial recharge of aquifers using available flow of the Carson River is one way to increase the amount of water in underground storage and maintain a dependable ground-water supply. Ground water can be artificially recharged by routing excess surface water or, after proper treatment, routing wastewater to infiltration basins or injection wells. Withdrawal wells would remove stored water when needed. As a first step, maps showing areas in Carson Valley with high, low, moderate and unknown potential for artificial recharge were developed on the basis of the distribution of geologic units, depth to water, specific yield, infiltration rate, and location of natural recharge and discharge. For recharge by means of infiltration, areas totaling 5,700 acres have high potential, 23,900 acres have moderate potential, and 6,200 acres have low potential. For recharge through injection, areas totaling 7,800 acres have high potential and 43,500 acres have moderate potential; 23,000 acres have unknown potential because data are lacking on subsurface conditions. A ground-water-flow model was used to assess the possible results of artificial recharge. Simulations with no accompanying ground-water withdrawal show that, when recharge by injection is simulated near the valley floor, heads in the semiconfined aquifer increase over much of the valley, floor; only about 20 percent of the recharged water is stored in the aquifer after 5 years and as much as 80 percent is lost to streamflow and evapotranspiration. When recharge is simulated on the eastern side of the valley, 80 percent of the recharged water remains in storage after 5 years. When recharge is simulated near the valley floor, more water is lost to discharge than when recharge is on the eastern side of the valley. When recharge is applied for long periods without accompanying withdrawal, recharged water moves downgradient to discharge areas. The recharge water that discharges to the surface-water system could in turn replenish base flow of the Carson River and benefit downstream users.

  17. Modeling spatiotemporal impacts of hydroclimatic extremes on groundwater recharge at a Mediterranean karst aquifer

    NASA Astrophysics Data System (ADS)

    Hartmann, Andreas; Mudarra, Matías; Andreo, Bartolomé; Marín, Ana; Wagener, Thorsten; Lange, Jens

    2014-08-01

    Karst aquifers provide large parts of the water supply for Mediterranean countries, though climate change is expected to have a significant negative impact on water availability. Recharge is therefore a key variable that has to be known for sustainable groundwater use. In this study, we present a new approach that combines two independent methods for karst recharge estimation. The first method derives spatially distributed information of mean annual recharge patterns through GIS analysis. The second is a process-based karst model that provides spatially lumped but temporally distributed information about recharge. By combining both methods, we add a spatial reference to the lumped simulations of the process-based model. In this way, we are able to provide spatiotemporal information of recharge and subsurface flow dynamics also during varying hydroclimatic conditions. We find that there is a nonlinear relationship between precipitation and recharge rates resulting in strong decreases of recharge following even moderate decreases of precipitation. This is primarily due to almost constant actual evapotranspiration amounts despite varying hydroclimatic conditions. During the driest year in the record, almost the entire precipitation was consumed as actual evapotranspiration and only little diffuse recharge took place at the high altitudes of our study site. During wettest year, recharge constituted a much larger fraction of precipitation and occurred at the entire study site. Our new method and our findings are significant for decision makers in similar regions that want to prepare for possible changes of hydroclimatic conditions in the future.

  18. Groundwater recharge at five representative sites in the Hebei Plain, China.

    PubMed

    Lu, Xiaohui; Jin, Menggui; van Genuchten, Martinus Th; Wang, Bingguo

    2011-01-01

    Accurate estimates of groundwater recharge are essential for effective management of groundwater, especially when supplies are limited such as in many arid and semiarid areas. In the Hebei Plain, China, water shortage is increasingly restricting socioeconomic development, especially for agriculture, which heavily relies on groundwater. Human activities have greatly changed groundwater recharge there during the past several decades. To obtain better estimates of recharge in the plain, five representative sites were selected to investigate the effects of irrigation and water table depth on groundwater recharge. At each site, a one-dimensional unsaturated flow model (Hydrus-1D) was calibrated using field data of climate, soil moisture, and groundwater levels. A sensitivity analysis of evapotranspirative fluxes and various soil hydraulic parameters confirmed that fine-textured surface soils generally generate less recharge. Model calculations showed that recharge on average is about 175 mm/year in the piedmont plain to the west, and 133 mm/year in both the central alluvial and lacustrine plains and the coastal plain to the east. Temporal and spatial variations in the recharge processes were significant in response to rainfall and irrigation. Peak time-lags between infiltration (rainfall plus irrigation) and recharge were 18 to 35 days in the piedmont plain and 3 to 5 days in the central alluvial and lacustrine plains, but only 1 or 2 days in the coastal plain. This implies that different time-lags corresponding to different water table depths must be considered when estimating or modeling groundwater recharge. PMID:20100294

  19. A generalized estimate of ground-water-recharge rates in the Lower Peninsula of Michigan

    USGS Publications Warehouse

    Holtschlag, David J.

    1997-01-01

    Ground-water recharge rates were estimated by analysis of streamflow, precipitation, and basin-characteristics data. Streamflow data were partitioned into ground-water-discharge and surface-water-runoff components. Regression equations relate ground-water discharge to precipitation at each basin. Basin-characteristics and long-term precipitation data were used to aid in the interpolation of recharge characteristics within gaged and ungaged areas. A multiple regression equation was developed to estimate spatial variation of recharge. The generalized estimate provides a consistent method for approximating recharge rates in the Lower Peninsula of Michigan.

  20. Seasonality of groundwater recharge in the Basin and Range Province, western North America

    NASA Astrophysics Data System (ADS)

    Neff, Kirstin Lynn

    Alluvial groundwater systems are an important source of water for communities and biodiverse riparian corridors throughout the arid and semi-arid Basin and Range Geological Province of western North America. These aquifers and their attendant desert streams have been depleted to support a growing population, while projected climate change could lead to more extreme episodes of drought and precipitation in the future. The only source of replenishment to these aquifers is recharge. This dissertation builds upon previous work to characterize and quantify recharge in arid and semi-arid basins by characterizing the intra-annual seasonality of recharge across the Basin and Range Province, and considering how climate change might impact recharge seasonality and volume, as well as fragile riparian corridors that depend on these hydrologic processes. First, the seasonality of recharge in a basin in the sparsely-studied southern extent of the Basin and Range Province is determined using stable water isotopes of seasonal precipitation and groundwater, and geochemical signatures of groundwater and surface water. In northwestern Mexico in the southern reaches of the Basin and Range, recharge is dominated by winter precipitation (69% +/- 42%) and occurs primarily in the uplands. Second, isotopically-based estimates of seasonal recharge fractions in basins across the region are compared to identify patterns in recharge seasonality, and used to evaluate a simple water budget-based model for estimating recharge seasonality, the normalized seasonal wetness index (NSWI). Winter precipitation makes up the majority of annual recharge throughout the region, and North American Monsoon (NAM) precipitation has a disproportionately weak impact on recharge. The NSWI does well in estimating recharge seasonality for basins in the northern Basin and Range, but less so in basins that experience NAM precipitation. Third, the seasonal variation in riparian and non-riparian vegetation greenness, represented by the normalized difference vegetation index (NDVI), is characterized in several of the study basins and climatic and hydrologic controls are identified. Temperature was the most significant driver of vegetation greenness, but precipitation and recharge seasonality played a significant role in some basins at some elevations. Major contributions of this work include a better understanding of recharge in a monsoon-dominated basin, the characterization of recharge seasonality at a regional scale, evaluation of an estimation method for recharge seasonality, and an interpretation of the interaction of seasonal hydrologic processes, vegetation dynamics, and climate change.

  1. Recharge processes in an alluvial aquifer riparian zone, Norman Landfill, Norman, Oklahoma, 1998-2000

    USGS Publications Warehouse

    Scholl, Martha; Christenson, Scott; Cozzarelli, Isabelle; Ferree, Dale; Jaeshke, Jeanne

    2005-01-01

    Analyses of stable isotope profiles (d2H and d18O) in the saturated zone, combined with water-table fluctuations, gave a comprehensive picture of recharge processes in an alluvial aquifer riparian zone. At the Norman Landfill U.S. Geological Survey Toxic Substances Hydrology research site in Norman, Oklahoma, recharge to the aquifer appears to drive biodegradation, contributing fresh supplies of electron acceptors for the attenuation of leachate compounds from the landfill. Quantifying recharge is a first step in studying this process in detail. Both chemical and physical methods were used to estimate recharge. Chemical methods included measuring the increase in recharge water in the saturated zone, as defined by isotopic signature, specific conductance or chloride measurements; and infiltration rate estimates using storm event isotopic signatures. Physical methods included measurement of water-table rise after individual rain events and on an approximately monthly time scale. Evapotranspiration rates were estimated using diurnal watertable fluctuations; outflux of water from the alluvial aquifer during the growing season had a large effect on net recharge at the site. Evaporation and methanogenesis gave unique isotopic signatures to different sources of water at the site, allowing the distinction of recharge using the offset of the isotopic signature from the local meteoric water line. The downward movement of water from large, isotopically depleted rain events in the saturated zone yielded recharge rate estimates (2.2 - 3.3 mm/day), and rates also were determined by observing changes in thickness of the layer of infiltrated recharge water at the top of the saturated zone (1.5 - 1.6 mm/day). Recharge measured over 2 years (1998-2000) in two locations at the site averaged 37 percent of rainfall, however, part of this water had only a short residence time in the aquifer. Isotopes showed recharge water entering the ground-water system in winter and spring, then being removed during the growing season by phreatophyte transpiration. Recharge timing was variable over the course of the study; July and August were the only months that had no recharge in both years. Recharge to the aquifer from the slough (wetland pond) was estimated at one location using the isotopic signature of water affected by evaporation. Recharge was correlated with the rainfall amount over the period of estimation, suggesting that recharge from the slough to the downgradient aquifer was an episodic process, corresponding to elevated water levels in the slough after large rain events.

  2. Use of soil moisture probes to estimate ground water recharge at an oil spill site

    USGS Publications Warehouse

    Delin, G.N.; Herkelrath, W.N.

    2005-01-01

    Soil moisture data collected using an automated data logging system were used to estimate ground water recharge at a crude oil spill research site near Bemidji, Minnesota. Three different soil moisture probes were tested in the laboratory as well as the field conditions of limited power supply and extreme weather typical of northern Minnesota: a self-contained reflectometer probe, and two time domain reflectometry (TDR) probes, 30 and 50 cm long. Recharge was estimated using an unsaturated zone water balance method. Recharge estimates for 1999 using the laboratory calibrations were 13 to 30 percent greater than estimates based on the factory calibrations. Recharge indicated by the self-contained probes was 170 percent to 210 percent greater than the estimates for the TDR probes regardless of calibration method. Results indicate that the anomalously large recharge estimates for the self-contained probes are not the result of inaccurate measurements of volumetric moisture content, but result from the presence of crude oil, or bore-hole leakage. Of the probes tested, the 50 cm long TDR probe yielded recharge estimates that compared most favorably to estimates based on a method utilizing water table fluctuations. Recharge rates for this probe represented 24 to 27 percent of 1999 precipitation. Recharge based on the 30 cm long horizontal TDR probes was 29 to 37 percent of 1999 precipitation. By comparison, recharge based on the water table fluctuation method represented about 29 percent of precipitation. (JAWRA) (Copyright ?? 2005).

  3. SWB-A modified Thornthwaite-Mather Soil-Water-Balance code for estimating groundwater recharge

    USGS Publications Warehouse

    Westenbroek, S.M.; Kelson, V.A.; Dripps, W.R.; Hunt, R.J.; Bradbury, K.R.

    2010-01-01

    A Soil-Water-Balance (SWB) computer code has been developed to calculate spatial and temporal variations in groundwater recharge. The SWB model calculates recharge by use of commonly available geographic information system (GIS) data layers in combination with tabular climatological data. The code is based on a modified Thornthwaite-Mather soil-water-balance approach, with components of the soil-water balance calculated at a daily timestep. Recharge calculations are made on a rectangular grid of computational elements that may be easily imported into a regional groundwater-flow model. Recharge estimates calculated by the code may be output as daily, monthly, or annual values.

  4. Seasonalizing mountain system recharge in semi-arid basins-climate change impacts.

    PubMed

    Ajami, Hoori; Meixner, Thomas; Dominguez, Francina; Hogan, James; Maddock, Thomas

    2012-01-01

    Climate variability and change impact groundwater resources by altering recharge rates. In semi-arid Basin and Range systems, this impact is likely to be most pronounced in mountain system recharge (MSR), a process which constitutes a significant component of recharge in these basins. Despite its importance, the physical processes that control MSR have not been fully investigated because of limited observations and the complexity of recharge processes in mountainous catchments. As a result, empirical equations, that provide a basin-wide estimate of mean annual recharge using mean annual precipitation, are often used to estimate MSR. Here North American Regional Reanalysis data are used to develop seasonal recharge estimates using ratios of seasonal (winter vs. summer) precipitation to seasonal actual or potential evapotranspiration. These seasonal recharge estimates compared favorably to seasonal MSR estimates using the fraction of winter vs. summer recharge determined from isotopic data in the Upper San Pedro River Basin, Arizona. Development of hydrologically based seasonal ratios enhanced seasonal recharge predictions and notably allows evaluation of MSR response to changes in seasonal precipitation and temperature because of climate variability and change using Global Climate Model (GCM) climate projections. Results show that prospective variability in MSR depends on GCM precipitation predictions and on higher temperature. Lower seasonal MSR rates projected for 2050-2099 are associated with decreases in summer precipitation and increases in winter temperature. Uncertainty in seasonal MSR predictions arises from the potential evapotranspiration estimation method, the GCM downscaling technique and the exclusion of snowmelt processes. PMID:22091994

  5. Simulation of runoff and recharge and estimation of constituent loads in runoff, Edwards aquifer recharge zone (outcrop) and catchment area, Bexar County, Texas, 1997-2000

    USGS Publications Warehouse

    Ockerman, Darwin J.

    2002-01-01

    The U.S. Geological Survey developed a watershed model (Hydrological Simulation Program?FORTRAN) to simulate runoff and recharge and to estimate constituent loads in surface-water runoff in the Edwards aquifer recharge zone (outcrop) and catchment area in Bexar County, Texas. Rainfall and runoff data collected during 1970?98 from four gaged basins in the outcrop and catchment area were used to calibrate and test the model. The calibration parameters were applied in simulations of the four calibration basins and six ungaged basins that compose the study area to obtain runoff and recharge volumes for 4 years, 1997?2000. In 1997, simulated runoff from the study area was 5.62 inches. Simulated recharge in the study area was 7.85 inches (20 percent of rainfall). In 1998, simulated runoff was 11.05 inches; simulated recharge was 10.99 inches (25 percent of rainfall). In 1999, simulated runoff was 0.66 inch; simulated recharge was 3.03 inches (19 percent of rainfall). In 2000, simulated runoff was 5.29 inches; simulated recharge was 7.19 inches (21 percent of rainfall). During 1997?2000, direct infiltration of rainfall accounted for about 56 percent of the total Edwards aquifer recharge in Bexar County. Streamflow losses contributed about 37 percent of the recharge; flood impoundment contributed 7 percent. The simulated runoff volumes were used with event-mean-concentration data from basins in the study area and from other Bexar County basins to compute constituent loads and yields for various land uses. Annual loads for suspended solids, dissolved solids, dissolved nitrite plus nitrate nitrogen, and total lead were consistently largest from undeveloped land and smallest from commercial land or transportation corridors. Annual loads and yields varied with rainfall, with the maximum loads produced in the wettest year (1998) and the minimum loads produced in the driest year (1999).

  6. Artificial recharge through a thick, heterogeneous unsaturated zone

    USGS Publications Warehouse

    Izbicki, J.A.; Flint, A.L.; Stamos, C.L.

    2008-01-01

    Thick, heterogeneous unsaturated zones away from large streams in desert areas have not previously been considered suitable for artificial recharge from ponds. To test the potential for recharge in these settings, 1.3 ?? 10 6 m3 of water was infiltrated through a 0.36-ha pond along Oro Grande Wash near Victorville, California, between October 2002 and January 2006. The pond overlies a regional pumping depression 117 m below land surface and is located where thickness and permeability of unsaturated deposits allowed infiltration and saturated alluvial deposits were sufficiently permeable to allow recovery of water. Because large changes in water levels caused by nearby pumping would obscure arrival of water at the water table, downward movement of water was measured using sensors in the unsaturated zone. The downward rate of water movement was initially as high as 6 m/d and decreased with depth to 0.07 m/d; the initial time to reach the water table was 3 years. After the unsaturated zone was wetted, water reached the water table in 1 year. Soluble salts and nitrate moved readily with the infiltrated water, whereas arsenic and chromium were less mobile. Numerical simulations done using the computer program TOUGH2 duplicated the downward rate of water movement, accumulation of water on perched zones, and its arrival at the water table. Assuming 10 ?? 10 6 m3 of recharge annually for 20 years, a regional ground water flow model predicted water level rises of 30 m beneath the ponds, and rises exceeding 3 m in most wells serving the nearby urban area.

  7. Representative recharge rates in a complex unsaturated hydrogeology

    SciTech Connect

    Vold, E.; Newman, B.; Birdsell, K.

    1997-02-01

    This study summarizes analyses used for the determination of representative recharge rates in a semi-arid terrain of complex topography for the purpose of modeling the performance assessment of a mesa top disposal facility. Four recharge rates are identified based on different terrains. The terrain is first broadly grouped into canyon bottoms and mesa tops, with each covering about half the topography. The canyon bottoms are considered wet or dry depending on the local infiltration conditions and the influence of mans` activities. The mesa tops are separated into locations which are undisturbed and disturbed by laboratory operations. Disturbed locations at the disposal facility include the disposal pits utilized for shallow land burial of low-level radioactive waste, covering approximately half the mesa top area. Several sources of data and analyses have been synthesized to estimate the resulting recharge rates. Data and analyses include: (1) detailed surface water balance calculations with site-specific parameter values as input; (2) chloride ion profiles and analysis of implied flux at several borehole locations; (3) analyses of liquid and vapor phase vertical flux from moisture profiles with stratigraphic unit averaged unsaturated hydrologic properties; (4) comparison of moisture content field data with values implied from Darcy flux calculations for assumed unit gradient conditions and for stratigraphic unit averaged unsaturated hydrologic properties; (5) liquid flux calculated under self-consistent gradients from field observed moisture profiles and analytic determinations of in-situ moisture potential and conductivity at limited locations; (6) distributions in near surface soil moisture contents expressed as an equivalent vertical flux under unit gradient assumptions; and (7) limited comparisons to tracers available from past disposal operations.

  8. Artificial recharge through a thick, heterogeneous unsaturated zone.

    PubMed

    Izbicki, John A; Flint, Alan L; Stamos, Christina L

    2008-01-01

    Thick, heterogeneous unsaturated zones away from large streams in desert areas have not previously been considered suitable for artificial recharge from ponds. To test the potential for recharge in these settings, 1.3 x 10(6) m(3) of water was infiltrated through a 0.36-ha pond along Oro Grande Wash near Victorville, California, between October 2002 and January 2006. The pond overlies a regional pumping depression 117 m below land surface and is located where thickness and permeability of unsaturated deposits allowed infiltration and saturated alluvial deposits were sufficiently permeable to allow recovery of water. Because large changes in water levels caused by nearby pumping would obscure arrival of water at the water table, downward movement of water was measured using sensors in the unsaturated zone. The downward rate of water movement was initially as high as 6 m/d and decreased with depth to 0.07 m/d; the initial time to reach the water table was 3 years. After the unsaturated zone was wetted, water reached the water table in 1 year. Soluble salts and nitrate moved readily with the infiltrated water, whereas arsenic and chromium were less mobile. Numerical simulations done using the computer program TOUGH2 duplicated the downward rate of water movement, accumulation of water on perched zones, and its arrival at the water table. Assuming 10 x 10(6) m(3) of recharge annually for 20 years, a regional ground water flow model predicted water level rises of 30 m beneath the ponds, and rises exceeding 3 m in most wells serving the nearby urban area. PMID:18194322

  9. Alternative Fuels Infrastructure Development

    SciTech Connect

    Bloyd, Cary N.

    2010-06-30

    This summary reviews the status of alternate transportation fuels development and utilization in Thailand. An understanding of the issues and experiences associated with the introduction of alternative fuels in other countries can help the US in anticipation potential problems as it introduces new automotive fuels. Thailand is of particular interest since it introduced E20 to its commercial market in 2007 and the US is now considering introducing E20 into the US market.

  10. Rechargeable thin film battery and method for making the same

    DOEpatents

    Goldner, Ronald B.; Liu, Te-Yang; Goldner, Mark A.; Gerouki, Alexandra; Haas, Terry E.

    2006-01-03

    A rechargeable, stackable, thin film, solid-state lithium electrochemical cell, thin film lithium battery and method for making the same is disclosed. The cell and battery provide for a variety configurations, voltage and current capacities. An innovative low temperature ion beam assisted deposition method for fabricating thin film, solid-state anodes, cathodes and electrolytes is disclosed wherein a source of energetic ions and evaporants combine to form thin film cell components having preferred crystallinity, structure and orientation. The disclosed batteries are particularly useful as power sources for portable electronic devices and electric vehicle applications where high energy density, high reversible charge capacity, high discharge current and long battery lifetimes are required.

  11. Rechargeable battery which combats shape change of the zinc anode

    NASA Technical Reports Server (NTRS)

    Cohn, E. M. (Inventor)

    1976-01-01

    A rechargeable cell or battery is provided in which shape change of the zinc anode is combatted by profiling the ionic conductivity of the paths between the electrodes. The ion flow is greatest at the edges of the electrodes and least at the centers, thereby reducing migration of the zinc ions from edges to the center of the anode. A number of embodiments are disclosed in which the strength and/or amount of electrolyte, and/or the number and/or size of the paths provided by the separator between the electrodes, are varied to provide the desired ionic conductivity profile.

  12. A 65 Ah rechargeable lithium molybdenum disulfide battery

    NASA Technical Reports Server (NTRS)

    Brandt, K.

    1986-01-01

    A rechargeable lithium molybdenum disulfide battery which has a number of superior performance characteristics which includes a high energy density, a high power density, and a long charge retention time was developed. The first cell sizes developed included a C size cell and an AA size cell. Over the last two years, a project to demonstrate the feasibility of the scale up to this technology to a BC size cell with 65 Ah capacity was undertaken. The objective was to develop, build, and test a .6 kWh storage battery consisting of 6 BC cells in series.

  13. PLATINUM AND FUEL CELLS

    EPA Science Inventory

    Platinum requirements for fuel cell vehicles (FCVS) have been identified as a concern and possible problem with FCV market penetration. Platinum is a necessary component of the electrodes of fuel cell engines that power the vehicles. The platinum is deposited on porous electrodes...

  14. Using Tracer Tests to Estimate Vertical Recharge and Evaluate Influencing Factors for Irrigated Agricultural Systems

    NASA Astrophysics Data System (ADS)

    Lin, D.; Jin, M.; Brusseau, M.; Ma, B.; Liu, Y.

    2013-12-01

    Accurate estimation of vertical groundwater recharge is critical for (semi) arid regions, especially in places such as the North China Plain where vertical recharge comprises the largest portion of recharge. Tracer tests were used to estimate vertical recharge beneath agricultural systems irrigated by groundwater, and to help delineate factors that influence recharge. Bromide solution was applied to trace infiltration in the vadose zone beneath irrigated agricultural fields (rotated winter wheat and summer maize, orchards, and cotton) and non-irrigated woodlands at both piedmont plain (Shijiazhaung) and alluvial and lacustrine plains (Hengshui) in the North China Plain. The tracer tests lasted for more than two years, and were conducted at a total of 37 sites. Tracer solution was injected into the subsurface at a depth of 1.2 m before the rainy season. Soil samples were then collected periodically to observe bromide transport and estimate recharge rates at the point-scale. For these experiments, the only irrigation the fields received was that applied by the landowners. In addition to these tests, a controlled irrigation experiment was conducted at a single wheat and maize site. The results showed that recharge rates were lower for the alluvial and lacustrine plains sites, which comprise finer-textured soils than those present in the piedmont plain. Specifically, the recharge rate ranged between 56-466 mm/a beneath wheat-maize, 110-564 mm/a beneath orchard, and 0-21 mm/a beneath woodlands with an average recharge coefficient of 0.17 for the piedmont plain sites, while the recharge rate ranged between 26-165 mm/a beneath wheat-maize, 6-40 mm/a beneath orchard, 87-319 mm/a beneath cotton, and 0-32 mm/a beneath woodlands with an average recharge coefficient of 0.10 for the alluvial and lacustrine plain sites. Irrigation provided the primary contribution to recharge, with precipitation providing a minor contribution. The results of both the uncontrolled and controlled irrigation experiments showed that recharge increased as irrigation quantity increased. Overall, recharge was lower for the fields with the rotation cultivation of winter wheat and summer maize compared to the aged apple orchard. In general, the irrigation quantity applied was larger than the requirement of the crops. Thus, managing the irrigation regime to insure that irrigation matches crop requirements would be helpful to better preserve groundwater resources and prevent water-table decline. The recharge rates obtained in this study will be used as input in a mathematical modeling effort designed to simulate the regional groundwater system in the North China Plain.

  15. Assessment of groundwater recharge in an ash-fall mantled karst aquifer of southern Italy

    NASA Astrophysics Data System (ADS)

    Manna, F.; Nimmo, J. R.; De Vita, P.; Allocca, V.

    2014-12-01

    In southern Italy, Mesozoic carbonate formations, covered by ash-fall pyroclastic soils, are large karst aquifers and major groundwater resources. For these aquifers, even though Allocca et al., 2014 estimated a mean annual groundwater recharge coefficient at regional scale, a more complete understanding of the recharge processes at small spatio-temporal scale is a primary scientific target. In this paper, we study groundwater recharge processes in the Acqua della Madonna test site (Allocca et al., 2008) through the integrated analysis of piezometric levels, rainfall, soil moisture and air temperature data. These were gathered with hourly frequency by a monitoring station in 2008. We applied the Episodic Master Recharge method (Nimmo et al., 2014) to identify episodes of recharge and estimate the Recharge to Precipitation Ratio (RPR) at both the individual-episode and annual time scales. For different episodes of recharge observed, RPR ranges from 97% to 37%, with an annual mean around 73%. This result has been confirmed by a soil water balance and the application of the Thornthwaite-Mather method to estimate actual evapotranspiration. Even though it seems higher than RPRs typical of some parts of the world, it is very close to the mean annual groundwater recharge coefficient estimated at the regional scale for the karst aquifers of southern Italy. In addition, the RPR is affected at the daily scale by both antecedent soil moisture and rainfall intensity, as demonstrated by a statistically significant multiple linear regression among such hydrological variables. In particular, the recharge magnitude is great for low storm intensity and high antecedent soil moisture value. The results advance the comprehension of groundwater recharge processes in karst aquifers, and the sensitivity of RPR to antecedent soil moisture and rainfall intensity facilitates the prediction of the influence of climate and precipitation regime change on the groundwater recharge process.

  16. Using 14C and 3H to understand groundwater flow and recharge in an aquifer window

    NASA Astrophysics Data System (ADS)

    Atkinson, A. P.; Cartwright, I.; Gilfedder, B. S.; Cendón, D. I.; Unland, N. P.; Hofmann, H.

    2014-12-01

    Knowledge of groundwater residence times and recharge locations is vital to the sustainable management of groundwater resources. Here we investigate groundwater residence times and patterns of recharge in the Gellibrand Valley, southeast Australia, where outcropping aquifer sediments of the Eastern View Formation form an "aquifer window" that may receive diffuse recharge from rainfall and recharge from the Gellibrand River. To determine recharge patterns and groundwater flow paths, environmental isotopes (3H, 14C, δ13C, δ18O, δ2H) are used in conjunction with groundwater geochemistry and continuous monitoring of groundwater elevation and electrical conductivity. The water table fluctuates by 0.9 to 3.7 m annually, implying recharge rates of 90 and 372 mm yr-1. However, residence times of shallow (11 to 29 m) groundwater determined by 14C are between 100 and 10 000 years, 3H activities are negligible in most of the groundwater, and groundwater electrical conductivity remains constant over the period of study. Deeper groundwater with older 14C ages has lower δ18O values than younger, shallower groundwater, which is consistent with it being derived from greater altitudes. The combined geochemistry data indicate that local recharge from precipitation within the valley occurs through the aquifer window, however much of the groundwater in the Gellibrand Valley predominantly originates from the regional recharge zone, the Barongarook High. The Gellibrand Valley is a regional discharge zone with upward head gradients that limits local recharge to the upper 10 m of the aquifer. Additionally, the groundwater head gradients adjacent to the Gellibrand River are generally upwards, implying that it does not recharge the surrounding groundwater and has limited bank storage. 14C ages and Cl concentrations are well correlated and Cl concentrations may be used to provide a first-order estimate of groundwater residence times. Progressively lower chloride concentrations from 10 000 years BP to the present day are interpreted to indicate an increase in recharge rates on the Barongarook High.

  17. Using 14C and 3H to understand groundwater flow and recharge in an aquifer window

    NASA Astrophysics Data System (ADS)

    Atkinson, A. P.; Cartwright, I.; Gilfedder, B. S.; Cendón, D. I.; Unland, N. P.; Hofmann, H.

    2014-06-01

    Knowledge of groundwater residence times and recharge locations are vital to the sustainable management of groundwater resources. Here we investigate groundwater residence times and patterns of recharge in the Gellibrand Valley, southeast Australia, where outcropping aquifer sediments of the Eastern View Formation form an "aquifer window" that may receive diffuse recharge and recharge from the Gellibrand River. To determine recharge patterns and groundwater flowpaths, environmental isotopes (3H, 14C, δ13C, δ18O, δ2H) are used in conjunction with groundwater geochemistry and continuous monitoring of groundwater elevation and electrical conductivity. Despite the water table fluctuating by 0.9-3.7 m annually producing estimated recharge rates of 90 and 372 mm yr-1, residence times of shallow (11-29 m) groundwater determined by 14C ages are between 100 and 10 000 years. 3H activities are negligible in most of the groundwater and groundwater electrical conductivity in individual areas remains constant over the period of study. Although diffuse local recharge is evident, the depth to which it penetrates is limited to the upper 10 m of the aquifer. Rather, groundwater in the Gellibrand Valley predominantly originates from the regional recharge zone, the Barongarook High, and acts as a regional discharge zone where upward head gradients are maintained annually, limiting local recharge. Additionally, the Gellibrand River does not recharge the surrounding groundwater and has limited bank storage. 14C ages and Cl concentrations are well correlated and Cl concentrations may be used to provide a first-order estimate of groundwater residence times. Progressively lower chloride concentrations from 10 000 years BP to the present day are interpreted to indicate an increase in recharge rates on the Barongarook High.

  18. Quantifying Groundwater Recharge Uncertainty: A Multiple-Model Framework and Case Study

    NASA Astrophysics Data System (ADS)

    Kikuchi, C.; Ferré, T. P. A.

    2014-12-01

    In practice, it is difficult to estimate groundwater recharge accurately. Despite this challenge, most recharge investigations produce a single, best estimate of recharge. However, there is growing recognition that quantification of natural recharge uncertainty is critical for groundwater management. We present a multiple-model framework for estimating recharge uncertainty. In addition, we show how direct water flux measurements can be used to reduce the uncertainty of estimates of total basin recharge for an arid, closed hydrologic basin in the Atacama Desert, Chile. We first formulated multiple hydrogeologic conceptual models of the basin based on existing data, and implemented each conceptual model for the purpose of conducting numerical simulations. For each conceptual model, groundwater recharge was inversely estimated; then, Null-Space Monte Carlo techniques were used to quantify the uncertainty on the initial estimate of total basin recharge. Second, natural recharge components - including both deep percolation and streambed infiltration - were estimated from field data. Specifically, vertical temperature profiles were measured in monitoring wells and streambeds, and water fluxes were estimated from thermograph analysis. Third, calculated water fluxes were incorporated as prior information to the model calibration and Null-Space Monte Carlo procedures, yielding revised estimates of both total basin recharge and associated uncertainty. The fourth and final component of this study uses value of information analyses to identify potentially informative locations for additional water flux measurements. The uncertainty quantification framework presented here is broadly transferable; furthermore, this research provides an applied example of the extent to which water flux measurements may serve to reduce groundwater recharge uncertainty at the basin scale.

  19. Spatial variability of ground-water recharge in selected principal aquifers of the eastern United States

    NASA Astrophysics Data System (ADS)

    Nolan, B. T.

    2004-12-01

    Over 500 vadose-zone sediment cores were collected as part of a regional study of ground water recharge to aquifers comprising glacial deposits and the Floridan, Coastal Lowlands, Piedmont and Blue Ridge, and North Atlantic Coastal Plain aquifer systems. Study objectives were to compare methods for estimating recharge; to compare and contrast recharge estimates for selected principal aquifers in the eastern U.S.; and to identify landscape factors that significantly influence recharge. We evaluated the Darcian, water-budget, water table-fluctuation, and tracer methods for estimating recharge. Sediment cores were analyzed for particle size distribution, moisture content, bulk density, organic matter, and selected anions. Direct measurements of unsaturated hydraulic conductivity (K) were made on a small number of cores by the steady-state centrifuge method. For all cores, K was derived from pedotransfer functions based on texture and bulk density data. Darcian water fluxes were calculated assuming either nonuniform matric potential or a unit gradient (q about equals K). Unit gradient estimates of recharge represent homogeneous sediments and thick layers in heterogeneous systems. Preliminary results indicate that the point estimates of recharge vary considerably within principal aquifers, and that median recharge is highest in glacial deposits in the northeastern U.S. Median recharge estimated by the Darcian method was similar to estimates derived from a base-flow index. Overall, there was good correspondence between unit-gradient and non-unit-gradient estimates of recharge, indicating that matric forces were not dominant in sampled sediment layers. Unit-gradient recharge was strongly related to moisture content and sediment texture. For sands, hydraulic conductivities derived from pedotransfer functions compared favorably with those measured by the centrifuge method. The pedotransfer method, however, overpredicted K for a silty sample with high moisture content. It is possible that the pedotransfer method is biased towards sandy samples because the empirical model on which it is based is calibrated to predominantly coarse-textured soils.

  20. Ground truthing groundwater-recharge estimates derived from remotely sensed evapotranspiration: a case in South Australia

    NASA Astrophysics Data System (ADS)

    Crosbie, Russell S.; Davies, Phil; Harrington, Nikki; Lamontagne, Sebastien

    2015-03-01

    Using a water balance to estimate groundwater recharge through the use of remotely sensed evapotranspiration offers a spatial and temporal density of data that other techniques cannot match. However, the estimates are uncertain and therefore ground truthing of the recharge estimates is necessary. This study, conducted in the south-east of South Australia, demonstrated that the raw water-balance estimates of recharge had a negative bias of 45 mm/yr when compared to 190 recharge estimates using the water-table fluctuation method over a 10-year period (2001-2010). As this bias was not related to the magnitude of the recharge estimated using the water-table fluctuation method, a simple offset was used to bias-correct the water-balance recharge estimates. The bias-corrected recharge estimates had a mean residual that was not significantly different from an independent set of 99 historical recharge estimates but did have a large mean absolute residual indicating a lack of precision. The value in this technique is the density of the data (250-m grid over 29,000 km2). The relationship between the water-table depth and net recharge under different vegetation types was investigated. Under pastures, there was no relationship with water-table depth, as the shallow roots do not intercept groundwater. However, under plantation forestry, there was a relationship between net recharge and water-table depth. Net recharge under plantation forestry growing on sandy soils was independent of the water table at around 6 m depth but, under heavier textured soils, the trees were using groundwater from depths of more than 20 m.

  1. Modeled impacts of predicted climate change on recharge and groundwater levels

    NASA Astrophysics Data System (ADS)

    Scibek, J.; Allen, D. M.

    2006-11-01

    A methodology is developed for linking climate models and groundwater models to investigate future impacts of climate change on groundwater resources. An unconfined aquifer, situated near Grand Forks in south central British Columbia, Canada, is used to test the methodology. Climate change scenarios from the Canadian Global Coupled Model 1 (CGCM1) model runs are downscaled to local conditions using Statistical Downscaling Model (SDSM), and the change factors are extracted and applied in LARS-WG stochastic weather generator and then input to the recharge model. The recharge model simulated the direct recharge to the aquifer from infiltration of precipitation and consisted of spatially distributed recharge zones, represented in the Hydrologic Evaluation of Landfill Performance (HELP) hydrologic model linked to a geographic information system (GIS). A three-dimensional transient groundwater flow model, implemented in MODFLOW, is then used to simulate four climate scenarios in 1-year runs (1961-1999 present, 2010-2039, 2040-2069, and 2070-2099) and compare groundwater levels to present. The effect of spatial distribution of recharge on groundwater levels, compared to that of a single uniform recharge zone, is much larger than that of temporal variation in recharge, compared to a mean annual recharge representation. The predicted future climate for the Grand Forks area from the downscaled CGCM1 model will result in more recharge to the unconfined aquifer from spring to the summer season. However, the overall effect of recharge on the water balance is small because of dominant river-aquifer interactions and river water recharge.

  2. Reconnaissance Estimates of Recharge Based on an Elevation-dependent Chloride Mass-balance Approach

    SciTech Connect

    Charles E. Russell; Tim Minor

    2002-08-31

    Significant uncertainty is associated with efforts to quantity recharge in arid regions such as southern Nevada. However, accurate estimates of groundwater recharge are necessary to understanding the long-term sustainability of groundwater resources and predictions of groundwater flow rates and directions. Currently, the most widely accepted method for estimating recharge in southern Nevada is the Maxey and Eakin method. This method has been applied to most basins within Nevada and has been independently verified as a reconnaissance-level estimate of recharge through several studies. Recharge estimates derived from the Maxey and Eakin and other recharge methodologies ultimately based upon measures or estimates of groundwater discharge (outflow methods) should be augmented by a tracer-based aquifer-response method. The objective of this study was to improve an existing aquifer-response method that was based on the chloride mass-balance approach. Improvements were designed to incorporate spatial variability within recharge areas (rather than recharge as a lumped parameter), develop a more defendable lower limit of recharge, and differentiate local recharge from recharge emanating as interbasin flux. Seventeen springs, located in the Sheep Range, Spring Mountains, and on the Nevada Test Site were sampled during the course of this study and their discharge was measured. The chloride and bromide concentrations of the springs were determined. Discharge and chloride concentrations from these springs were compared to estimates provided by previously published reports. A literature search yielded previously published estimates of chloride flux to the land surface. {sup 36}Cl/Cl ratios and discharge rates of the three largest springs in the Amargosa Springs discharge area were compiled from various sources. This information was utilized to determine an effective chloride concentration for recharging precipitation and its associated uncertainty via Monte Carlo simulations. Previously developed isohyetal maps were utilized to determine the mean and standard deviation of precipitation within the area. A digital elevation model was obtained to provide elevation information. A geologic model was obtained to provide the spatial distribution of alluvial formations. Both were used to define the lower limit of recharge. In addition, 40 boreholes located in alluvial sediments were drilled and sampled in an attempt to support the argument that the areal distribution of alluvial sediments can be used to define a zone of negligible recharge. The data were compiled in a geographic information system and used in a Monte Carlo analysis to determine recharge occurring within the study area. Results of the analysis yielded estimates of the mean and standard deviation of recharge occurring within the study area (28.168 x 10{sup 6} m{sup 3} yr{sup -1} and 7.008 x 10{sup 6} m{sup 3} yr{sup -1}, and 26.838 x 10{sup 6} m{sup 3} yr{sup -1} and 6.928 x 10{sup 6} m{sup 3} yr{sup -1}) for two sets of simulations using alternate definitions of the lower limit of recharge. A sensitivity analysis determined the recharge estimates were most sensitive to uncertainty associated with the chloride concentration of the spring discharge. The second most sensitive parameter was the uncertainty associated with the mean precipitation within the recharge areas. Comparison of the analysis to previously published estimates of recharge revealed mixed results with the recharge estimates derived during the course of this project generally greater relative to previously published estimates.

  3. Extracellular enzyme activities and nutrient availability during artificial groundwater recharge.

    PubMed

    Kolehmainen, Reija E; Korpela, Jaana P; Münster, Uwe; Puhakka, Jaakko A; Tuovinen, Olli H

    2009-02-01

    Natural organic matter (NOM) removal is the main objective of artificial groundwater recharge (AGR) for drinking water production and biodegradation plays a substantial role in this process. This study focused on the biodegradation of NOM and nutrient availability for microorganisms in AGR by the determination of extracellular enzyme activities (EEAs) and nutrient concentrations along a flow path in an AGR aquifer (Tuusula Water Works, Finland). Natural groundwater in the same area but outside the influence of recharge was used as a reference. Determination of the specific alpha-d-glucosidase (alpha-Glu), beta-d-glucosidase (beta-Glu), phosphomonoesterase (PME), leucine aminopeptidase (LAP) and acetate esterase (AEST) activities by fluorogenic model substrates revealed major increases in the enzymatic hydrolysis rates in the aquifer within a 10m distance from the basin. The changes in the EEAs along the flow path occurred simultaneously with decreases in nutrient concentrations. The results support the assumption that the synthesis of extracellular enzymes in aquatic environments is up and down regulated by nutrient availability. The EEAs in the basin sediment and pore water samples (down to 10cm) were in the same order of magnitude as in the basin water, suggesting similar nutritional conditions. Phosphorus was likely to be the limiting nutrient at this particular AGR site. Furthermore, the extracellular enzymes functioned in a synergistic and cooperative way. PMID:19028394

  4. Clogging in Managed Aquifer Recharge: Hydrodynamics and Geochemistry

    NASA Astrophysics Data System (ADS)

    Mays, D. C.

    2013-12-01

    Managed aquifer recharge (MAR) is the engineered process by which water is delivered into an aquifer for storage, transmission, or treatment. Perhaps the most significant technical challenge in MAR is clogging, a detrimental reduction of permeability in the aquifer porous media. This presentation describes research from the allied fields of water treatment, soil science, and petrology, each of which sheds light on the mechanisms by which hydrodynamics and geochemistry influence clogging in MAR. The primary focus is clogging by suspended solids, especially clay colloids, which are ubiquitous in natural porous media. When colloids deposit in aquifers, they reduce the effective porosity and alter the pore space geometry, both of which can inhibit the flow of groundwater. Management of clogging is complicated by the complexity inherent in this system, in which hydrodynamics, geochemistry, clay mineralogy, and colloidal effects each play a role. This presentation will briefly review colloid filtration, mobilization, and clogging models, then highlight the key physical and chemical variables that control clogging. It will be argued that clogging in managed aquifer recharge is analogous to clogging in soils or hydrocarbon reservoirs, rather than to clogging in granular media filters used for water treatment. Based on this analogy, the presentation will conclude with several recommendations to prevent or manage clogging in MAR.

  5. Exploratory development of an electrically rechargeable lithium battery

    NASA Astrophysics Data System (ADS)

    Abraham, K. M.; Goldman, J. L.; Dempsey, M. D.; Holleck, G. L.

    1980-10-01

    The cathodic behavior or V6013 was investigated in rechargeable Li cells of the type, Li/2Me-THF,LiAsF6/V6013,C. Two forms of V6013 were synthesized and characterized. These were a stoichiometric form, i.e., V02.17, and a slightly non-stoichiometric form, i.e., V02.19. Stoichiometric V6013 was prepared by heating requisite quantities of V205 and V powder for 24 hrs. at 650 C. The slightly non-stoichiometric V6013 was prepared by the thermal decomposition of NH4V03 at 450 C. The discharge characteristics of the stoichiometric oxide at 60 C were similar to that of non-stoichiometric oxide at room temperature. The rechargeability of both the oxides were found to be sensitive to the lower voltage cutoff. The safest limits of cycling were 3.0 and 1.9V. Potentiostatic discharges of the oxides between 1.9 and 1.3V revealed a high capacity irreversible reduction process at about 1.6V. Three types of hermetically sealed cells were constructed and tested. In a high capacity (5Ah) prismatic cell utilizing the non-stoichiometric oxide, energy densities of 106 Whr/kg and 190 Whr/DM3 were achieved.

  6. Recharge and sustainability of a coastal aquifer in northern Albania

    NASA Astrophysics Data System (ADS)

    Kumanova, X.; Marku, S.; Fröjdö, S.; Jacks, G.

    2014-06-01

    The River Mati in Albania has formed a coastal plain with Holocene and Pleistocene sediments. The outer portion of the plain is clay, with three underlying aquifers that are connected to an alluvial fan at the entry of the river into the plain. The aquifers supply water for 240,000 people. Close to the sea the aquifers are brackish. The brackish water is often artesian and found to be thousands of years old. Furthermore, the salinity, supported by δ18O results, does not seem to be due to mixing with old seawater but due to diffusion from intercalated clay layers. Heavy metals from mines in the upstream section of River Mati are not an immediate threat, as the pH buffering of the river water is good. Moreover, the heavy metals are predominantly found in suspended and colloidal phases. Two sulphur isotope signatures, one mirroring seawater sulphate in the brackish groundwater (δ34S >21 ‰) and one showing the influence of sulphide in the river and the fresh groundwater (δ34S <10 ‰), indicate that the groundwater in the largest well field is recharged from the river. The most serious threat is gravel extraction in the alluvial fan, decreasing the hydraulic head necessary for recharge and causing clogging of sediments.

  7. Natural water purification and water management by artificial groundwater recharge.

    PubMed

    Balke, Klaus-Dieter; Zhu, Yan

    2008-03-01

    Worldwide, several regions suffer from water scarcity and contamination. The infiltration and subsurface storage of rain and river water can reduce water stress. Artificial groundwater recharge, possibly combined with bank filtration, plant purification and/or the use of subsurface dams and artificial aquifers, is especially advantageous in areas where layers of gravel and sand exist below the earth's surface. Artificial infiltration of surface water into the uppermost aquifer has qualitative and quantitative advantages. The contamination of infiltrated river water will be reduced by natural attenuation. Clay minerals, iron hydroxide and humic matter as well as microorganisms located in the subsurface have high decontamination capacities. By this, a final water treatment, if necessary, becomes much easier and cheaper. The quantitative effect concerns the seasonally changing river discharge that influences the possibility of water extraction for drinking water purposes. Such changes can be equalised by seasonally adapted infiltration/extraction of water in/out of the aquifer according to the river discharge and the water need. This method enables a continuous water supply over the whole year. Generally, artificially recharged groundwater is better protected against pollution than surface water, and the delimitation of water protection zones makes it even more save. PMID:18357624

  8. Natural water purification and water management by artificial groundwater recharge

    PubMed Central

    Balke, Klaus-Dieter; Zhu, Yan

    2008-01-01

    Worldwide, several regions suffer from water scarcity and contamination. The infiltration and subsurface storage of rain and river water can reduce water stress. Artificial groundwater recharge, possibly combined with bank filtration, plant purification and/or the use of subsurface dams and artificial aquifers, is especially advantageous in areas where layers of gravel and sand exist below the earth’s surface. Artificial infiltration of surface water into the uppermost aquifer has qualitative and quantitative advantages. The contamination of infiltrated river water will be reduced by natural attenuation. Clay minerals, iron hydroxide and humic matter as well as microorganisms located in the subsurface have high decontamination capacities. By this, a final water treatment, if necessary, becomes much easier and cheaper. The quantitative effect concerns the seasonally changing river discharge that influences the possibility of water extraction for drinking water purposes. Such changes can be equalised by seasonally adapted infiltration/extraction of water in/out of the aquifer according to the river discharge and the water need. This method enables a continuous water supply over the whole year. Generally, artificially recharged groundwater is better protected against pollution than surface water, and the delimitation of water protection zones makes it even more save. PMID:18357624

  9. Tritium tracer test to estimate aquifer recharge under irrigated conditions

    NASA Astrophysics Data System (ADS)

    Jimenez-Martinez, J.; Tamoh, K.; Candela, L.

    2009-12-01

    Environmental tracers, as tritium, have been generally used to estimate aquifer recharge under natural conditions. A tritium tracer test to estimate recharge under semi-arid and irrigated conditions is presented. The test was carried out in an experimental plot under drip irrigation, located in SE Spain, with annual row crops (rotation lettuce and melon), following common agricultural practices in open air. Tritiated water was applied as an irrigation pulse, soil cores were taken at different depths and a liquid scintillation analyzer was used to measure the concentration of tritium in soil samples. Transport of tritium was simulated with SOLVEG code, a one-dimensional numerical model for simulating transport of heat, water and tritiated water in liquid and gas phase, which has been modified and adapted for this experience, including ground cover, root growth and root water uptake. One crop has been used to calibrate the modeling approach and other three crops to validate it. Results of flow and transport modelling show a good agreement between observed and estimated tritium concentration profile. For the period October 2007-September 2008, total drainage obtained value was 441 mm.

  10. Recharge Mechanism to North-Western Sahara Aquifer System (NWSAS) Using Environmental Isotopes

    NASA Astrophysics Data System (ADS)

    Al-Gamal, Samir

    2010-05-01

    A comprehensive understanding is highly needed for any successful transboundary cooperation policy. Moreover, an analysis of the NWSAS can be of particular interest for policy makers and researchers. This paper aims to reveals and to assess the renewability of North Western Sahara Aquifer System(NWSAS) as one of the major transboundary multi-layered aquifer system, in North Africa, shared by Algeria, Tunisia, and Libya and is often referred to as the Système Aquifère du Sahara Septentrional (SASS).The paper is primarily intended for exploring whether it receives a considerable fraction of modern water as recharge or it is at risk of being depleted and excessively pumped, where the main challenge for NWSAS ,is that it should be abstracted rationally for equitable use. Environmental isotopes data of δ18O, δ2H, 3H ,14C as well as characteristics of d-excess are used to illustrate whether NSWAS is renewable or non-renewable resource.Geochemical, hydrological and statistical evidences supporting the renewability of NWSAS are provided through pairs of cross-plots . The study has clearly indicated that NWSAS is receiving a considerable fraction of modern water as recharge to the aquifer because of the following reasons; Firstly, the moderately depleted delta values of O-18 and H-2 of water from Sahara Atlas in Algeria and the Dahar and the Dj. Nefoussa in Tunisia and Libya with δ18O content (- 6.0‰ to -5.0‰) compared with that of palaeowater (-7.0 to -9.0 ‰) indicate a considerable fraction of modern water recharging NWSAS.This considerable fraction of modern water should be attributed to originate from the present-day precipitation (-6.5‰).Secondly, the presence of significant amount of 14C >2 % and 3H > 5TU., frequently found in data should be attributed to a mixing with shallow and modern water, where old water practically contains no 14C. The foregoing facts are in good agreement with the results of conventional hydrologic approach. This would contradicts the assumption that the NWSAS is non-renewable water resource. In this context, the NWSAS is being located in one of the driest regions on the planet, these huge resources have been recognized to be of great importance to the socio-economic development of its riparian countries. So the present paper addresses the necessity of identifying specific cooperation problems which evolve out of these hydrogeological attributes and prevalent use patterns. Accordingly, the description of NWSAS as non renewable, devoid of any meaningful recharge , a rather stagnant water body, disconnected from any surface water body in addition to its classification as "non-renewable" would therefore be misleading and represents one of the most obvious inaccuracy as well. Keywords stable isotopes of 18O and 2H, unstable isotopes of 14C and 3H.renewal , socio-economic development, Riparian,

  11. An assessment of recharge possibility to North-Western Sahara Aquifer System (NWSAS) using environmental isotopes

    NASA Astrophysics Data System (ADS)

    Al-Gamal, Samir Anwar

    2011-02-01

    SummaryA comprehensive understanding of the groundwater dynamics of a transboundary aquifer system is highly needed for any successful transboundary cooperation policy. Moreover, an analysis of the NWSAS can be of particular interest for policy makers and researchers. This paper aims to reveals and to assess the renewability of North-Western Sahara Aquifer System (NWSAS) as one of the major transboundary multi-layered aquifer system, in North Africa, shared by Algeria, Tunisia, and Libya and is often referred to as the Système Aquifère du Sahara Septentrional (SASS). The paper is primarily intended for exploring whether it receives a considerable fraction of modern water as recharge or it is at risk of being depleted and excessively pumped, where the main challenge for NWSAS, is that it should be abstracted rationally for equitable use. Environmental isotopes data of δ 18O, δ 2H, 3H, 14C as well as characteristics of d-excess are used to illustrate whether NSWAS is renewable or non-renewable resource. Geochemical, hydrological and statistical evidences supporting the renewability of NWSAS are provided through pairs of cross-plots. The study has clearly indicated that NWSAS is receiving a considerable fraction of modern water as recharge to the aquifer because of the following reasons: Firstly, the moderately depleted delta values of δ 18O and δ 2H of water from Sahara Atlas in Algeria and the Dahar and the Dj. Nefoussa in Tunisia and Libya with δ 18O content (-6.0‰ to -5.0‰) compared with that of palaeowater (-7.0‰ to -9.0‰) indicate an appreciable fraction of modern water recharging NWSAS. This appreciable fraction of modern water should be attributed to originate from the present-day precipitation (-6.5‰). Secondly, the presence of significant amount of 14C > 2% and 3H > 5 TU, frequently found in data should be attributed to a mixing with shallow and modern water, where old water practically contains no 14C. The foregoing facts are in good agreement with the results of conventional hydrologic approach. This would contradict the assumption that the NWSAS is non-renewable water resource. In this context, the NWSAS is being located in one of the driest regions on the planet; these huge resources have been recognized to be of great importance to the socio-economic development of its riparian countries. So the present paper addresses the necessity of identifying specific cooperation problems which evolve out of these hydro geological attributes and prevalent use patterns. Accordingly, the description of NWSAS as non-renewable, devoid of any meaningful recharge, a rather stagnant water body, disconnected from any surface water body in addition to its classification as "non-renewable" would therefore be misleading and represents one of the most obvious inaccuracy as well.

  12. Biological Sulfate Reduction Rates in Hydrothermal Recharge Zones

    NASA Astrophysics Data System (ADS)

    Crowell, B.; Lowell, R. P.

    2007-12-01

    We develop a model to determine the rate of removal of seawater sulfate in the recharge regions of deep-sea hydrothermal systems as a result of biogenic sulfate reduction. The rate of sulfate reduction as a function of temperature derived from laboratory measurements on cores from the Guaymas Basin in Mexico [Jorgensen et al., 1992] is incorporated into a steady state 1-D advection-diffusion temperature equation, and a 1-D, steady- state, advection dominated conservation of solute equation. The diffusivity of sulfate in seawater is on the order of ~ 10-10 m2/s, and unless the flow speeds are < 10-12 m/s, the effects of diffusion are negligible, except within thin diffusive boundary layers. This model is then compared with a model that utilizes Gibbs free energy to quantify biogenic sulfate reduction [Bach and Edwards, 2003] in the upper oceanic crust of aging lithosphere. Using the high rates determined by Jorgensen et al. [1992], our model indicates that biological activity would reduce all seawater sulfate transported into the system within the upper 10 meters or less of the crust, which is inconsistent with the estimates of Bach and Edwards [2003]. Sulfate concentrations from ODP borehole Legs 64 and 168, at the sedimented Guaymas Basin and Juan de Fuca Ridge, respectively, show that most of the seawater sulfate is removed in the upper 100 meters. If the sulfate is assumed to all be reduced biogenically, the sulfate reduction rates at the ODP sites are at least 2 orders of magnitude less than the laboratory estimates of Jorgenson et al. [1992]. Finally, we compare the rate of seawater sulfate removal as a result of the precipitation of anhydrite, with the rate of biogenic sulfate reduction. We find that if hydrothermal recharge occurs rapidly through highly permeable faults, that biogenic sulfate reduction is negligible and that anhydrite precipitation would rapidly clog the recharge zone [Lowell and Yao, 2002]. If recharge occurs through broad zones of slow downwelling (u recharge zones at ocean ridge crests, J. Geophys. Res., 107(B9), 2183, doi:10.1029/2001JB001289.

  13. Biological Sulfate Reduction Rates in Hydrothermal Recharge Zones

    NASA Astrophysics Data System (ADS)

    Crowell, B.; Lowell, R. P.

    2004-12-01

    We develop a model to determine the rate of removal of seawater sulfate in the recharge regions of deep-sea hydrothermal systems as a result of biogenic sulfate reduction. The rate of sulfate reduction as a function of temperature derived from laboratory measurements on cores from the Guaymas Basin in Mexico [Jorgensen et al., 1992] is incorporated into a steady state 1-D advection-diffusion temperature equation, and a 1-D, steady- state, advection dominated conservation of solute equation. The diffusivity of sulfate in seawater is on the order of ~ 10-10 m2/s, and unless the flow speeds are < 10-12 m/s, the effects of diffusion are negligible, except within thin diffusive boundary layers. This model is then compared with a model that utilizes Gibbs free energy to quantify biogenic sulfate reduction [Bach and Edwards, 2003] in the upper oceanic crust of aging lithosphere. Using the high rates determined by Jorgensen et al. [1992], our model indicates that biological activity would reduce all seawater sulfate transported into the system within the upper 10 meters or less of the crust, which is inconsistent with the estimates of Bach and Edwards [2003]. Sulfate concentrations from ODP borehole Legs 64 and 168, at the sedimented Guaymas Basin and Juan de Fuca Ridge, respectively, show that most of the seawater sulfate is removed in the upper 100 meters. If the sulfate is assumed to all be reduced biogenically, the sulfate reduction rates at the ODP sites are at least 2 orders of magnitude less than the laboratory estimates of Jorgenson et al. [1992]. Finally, we compare the rate of seawater sulfate removal as a result of the precipitation of anhydrite, with the rate of biogenic sulfate reduction. We find that if hydrothermal recharge occurs rapidly through highly permeable faults, that biogenic sulfate reduction is negligible and that anhydrite precipitation would rapidly clog the recharge zone [Lowell and Yao, 2002]. If recharge occurs through broad zones of slow downwelling (u < 10-9 m/s); however, anhydrite precipitation would seal pore on the order of thousands of years even in the absence of biogenic sulfate reduction. At these slower flow speeds, the biogenic sulfate reduction may provide an important mechanism for the removal of seawater sulfate from the deeper parts of the reaction zone. Bach, W. and K.J. Edwards (2003), Iron and sulfide oxidation within the basaltic ocean crust: Implications for chemolithoautotrophic microbial biomass production, Geochim.Cosmochim. Acta, 67, 3871-3887. Jorgensen, B.B., M.F. Isaksen and H.W. Jannasch (1992), Bacterial sulfate reduction above 100 degrees C in deep-sea hydrothermal vent sediments, Science, 258, 1756-1757. Lowell, R.P. and Y. Yao (2002), Anhydrite precipitation and the extent of hydrothermal recharge zones at ocean ridge crests, J. Geophys. Res., 107(B9), 2183, doi:10.1029/2001JB001289.

  14. Facile Synthesis of Lithium Sulfide Nanocrystals for Use in Advanced Rechargeable Batteries.

    PubMed

    Li, Xuemin; Wolden, Colin A; Ban, Chunmei; Yang, Yongan

    2015-12-30

    This work reports a new method of synthesizing anhydrous lithium sulfide (Li2S) nanocrystals and demonstrates their potential as cathode materials for advanced rechargeable batteries. Li2S is synthesized by reacting hydrogen sulfide (H2S) with lithium naphthalenide (Li-NAP), a thermodynamically spontaneous reaction that proceeds to completion rapidly at ambient temperature and pressure. The process completely removes H2S, a major industrial waste, while cogenerating 1,4-dihydronaphthalene, itself a value-added chemical that can be used as liquid fuel. The phase purity, morphology, and homogeneity of the resulting nanopowders were confirmed by X-ray diffraction and scanning electron microscopy. The synthesized Li2S nanoparticles (100 nm) were assembled into cathodes, and their performance was compared to that of cathodes fabricated using commercial Li2S micropowders (1-5 μm). Electrochemical analyses demonstrated that the synthesized Li2S were superior in terms of (dis)charge capacity, cycling stability, output voltage, and voltage efficiency. PMID:26633238

  15. Facile synthesis of lithium sulfide nanocrystals for use in advanced rechargeable batteries

    DOE PAGESBeta

    Li, Xuemin; Wolden, Colin A.; Ban, Chunmei; Yang, Yongan

    2015-12-03

    This work reports a new method of synthesizing anhydrous lithium sulfide (Li2S) nanocrystals and demonstrates their potential as cathode materials for advanced rechargeable batteries. Li2S is synthesized by reacting hydrogen sulfide (H2S) with lithium naphthalenide (Li-NAP), a thermodynamically spontaneous reaction that proceeds to completion rapidly at ambient temperature and pressure. The process completely removes H2S, a major industrial waste, while cogenerating 1,4-dihydronaphthalene, itself a value-added chemical that can be used as liquid fuel. The phase purity, morphology, and homogeneity of the resulting nanopowders were confirmed by X-ray diffraction and scanning electron microscopy. The synthesized Li2S nanoparticles (100 nm) were assembledmore » into cathodes, and their performance was compared to that of cathodes fabricated using commercial Li2S micropowders (1–5 μm). As a result, electrochemical analyses demonstrated that the synthesized Li2S were superior in terms of (dis)charge capacity, cycling stability, output voltage, and voltage efficiency.« less

  16. Facile synthesis of lithium sulfide nanocrystals for use in advanced rechargeable batteries

    SciTech Connect

    Li, Xuemin; Wolden, Colin A.; Ban, Chunmei; Yang, Yongan

    2015-12-03

    This work reports a new method of synthesizing anhydrous lithium sulfide (Li2S) nanocrystals and demonstrates their potential as cathode materials for advanced rechargeable batteries. Li2S is synthesized by reacting hydrogen sulfide (H2S) with lithium naphthalenide (Li-NAP), a thermodynamically spontaneous reaction that proceeds to completion rapidly at ambient temperature and pressure. The process completely removes H2S, a major industrial waste, while cogenerating 1,4-dihydronaphthalene, itself a value-added chemical that can be used as liquid fuel. The phase purity, morphology, and homogeneity of the resulting nanopowders were confirmed by X-ray diffraction and scanning electron microscopy. The synthesized Li2S nanoparticles (100 nm) were assembled into cathodes, and their performance was compared to that of cathodes fabricated using commercial Li2S micropowders (1–5 μm). As a result, electrochemical analyses demonstrated that the synthesized Li2S were superior in terms of (dis)charge capacity, cycling stability, output voltage, and voltage efficiency.

  17. Fuel-Cell Power Systems Incorporating Mg-Based H2 Generators

    NASA Technical Reports Server (NTRS)

    Kindler, Andrew; Narayan, Sri R.

    2009-01-01

    Two hydrogen generators based on reactions involving magnesium and steam have been proposed as means for generating the fuel (hydrogen gas) for such fuel-cell power systems as those to be used in the drive systems of advanced motor vehicles. The hydrogen generators would make it unnecessary to rely on any of the hydrogen storage systems developed thus far that are, variously, too expensive, too heavy, too bulky, and/or too unsafe to be practical. The two proposed hydrogen generators are denoted basic and advanced, respectively. In the basic hydrogen generator (see figure), steam at a temperature greater than or equals 330 C would be fed into a reactor charged with magnesium, wherein hydrogen would be released in the exothermic reaction Mg + H2O yields MgO + H2. The steam would be made in a flash boiler. To initiate the reaction, the boiler could be heated electrically by energy borrowed from a storage battery that would be recharged during normal operation of the associated fuel-cell subsystem. Once the reaction was underway, heat from the reaction would be fed to the boiler. If the boiler were made an integral part of the hydrogen-generator reactor vessel, then the problem of transfer of heat from the reactor to the boiler would be greatly simplified. A pump would be used to feed water from a storage tank to the boiler.

  18. Fossil fuels -- future fuels

    SciTech Connect

    1998-03-01

    Fossil fuels -- coal, oil, and natural gas -- built America`s historic economic strength. Today, coal supplies more than 55% of the electricity, oil more than 97% of the transportation needs, and natural gas 24% of the primary energy used in the US. Even taking into account increased use of renewable fuels and vastly improved powerplant efficiencies, 90% of national energy needs will still be met by fossil fuels in 2020. If advanced technologies that boost efficiency and environmental performance can be successfully developed and deployed, the US can continue to depend upon its rich resources of fossil fuels.

  19. Setting up a groundwater recharge model for an arid karst system using time lapse camera data

    NASA Astrophysics Data System (ADS)

    Schulz, Stephan; de Rooij, Gerrit H.; Michelsen, Nils; Rausch, Randolf; Siebert, Christian; Schüth, Christoph; Merz, Ralf

    2015-04-01

    Groundwater is the principal water resource in most dryland areas. Therefore, its replenishment rate is of great importance for water management. The amount of groundwater recharge depends on the climatic conditions, but also on the geological conditions, soil properties and vegetation. In dryland areas, outcrops of karst aquifers often receive enhanced recharge rates compared to other geological settings. Especially in areas with exposed karst features like sinkholes or open shafts rainfall accumulates in channels and discharges directly into the aquifer. Using the example of the As Sulb plateau in Saudi Arabia this study introduces a cost-effective and robust method for recharge monitoring and modelling in karst outcrops. The measurement of discharge of a small catchment (4.0 x 104 m2) into a sinkhole, and hence the direct recharge into the aquifer, was carried out with a time lapse camera observing a v-notch weir. During the monitoring period of two rainy seasons (autumn 2012 to spring 2014) four recharge events were recorded. Afterwards, recharge data as well as proxy data about the drying of the sediment cover are used to set up a conceptual water balance model. This model was run for 17 years (1971 to 1986 and 2012 to 2014). Simulation results show highly variable seasonal recharge-precipitation-ratios, which underlines the nonlinearity between recharge and precipitation in dryland areas. Besides the amount of precipitation this ratio is strongly influenced by the interannual distribution of rainfall events.

  20. Hydropedologic Analysis of Ground-Water Recharge at the Field Scale

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Estimating ground-water recharge is an important element in water resources characterization, vulnerability assessment, and utilization. Contaminant sources often occur in the unsaturated zone where ground-water recharge may mobilize it to migrate into a water table aquifer. Cumulative soil water...

  1. HYDRUS-1D Modeling of an Irrigated Agricultural Plot with Application to Aquifer Recharge Estimation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variety of methods are available for estimating aquifer recharge in semi-arid regions, each with advantages and disadvantages. We are investigating a procedure for estimating recharge in an irrigated basin. The method involves computing irrigation return flows based on HYDRUS-1D modeling of root z...

  2. EVALUATING UNCERTAINTIES IN GROUND-WATER RECHARGE ESTIMATES THROUGH ADVANCED MONITORING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Risk, as estimated by many multimedia environmental models, is highly sensitive to infiltration and ground-water recharge. This field study used high-frequency monitoring of vadose-zone water content and piezometric levels to build confidence in modeling of infiltration and ground-water recharge. ...

  3. Fullerenes: non-transition metal clusters as rechargeable magnesium battery cathodes.

    PubMed

    Zhang, Ruigang; Mizuno, Fuminori; Ling, Chen

    2015-01-21

    We discovered that non-transition metal clusters have great potential as rechargeable Mg battery cathodes. Fullerene (C60), one of the prototype materials, was discharged and recharged with a remarkable rate capability. This unique rate performance is attributed to its capability to delocalize electrons on the entire cluster rather than to individual atoms. PMID:25461490

  4. Inferring time-varying recharge from inverse analysis of long-term water levels

    USGS Publications Warehouse

    Dickinson, J.E.; Hanson, R.T.; Ferre, T. P. A.; Leake, S.A.

    2004-01-01

    Water levels in aquifers typically vary in response to time-varying rates of recharge, suggesting the possibility of inferring time-varying recharge rates on the basis of long-term water level records. Presumably, in the southwestern United States (Arizona, Nevada, New Mexico, southern California, and southern Utah), rates of mountain front recharge to alluvial aquifers depend on variations in precipitation rates due to known climate cycles such as the El Nin??o-Southern Oscillation index and the Pacific Decadal Oscillation. This investigation examined the inverse application of a one-dimensional analytical model for periodic flow described by Lloyd R. Townley in 1995 to estimate periodic recharge variations on the basis of variations in long-term water level records using southwest aquifers as the case study. Time-varying water level records at various locations along the flow line were obtained by simulation of forward models of synthetic basins with applied sinusoidal recharge of either a single period or composite of multiple periods of length similar to known climate cycles. Periodic water level components, reconstructed using singular spectrum analysis (SSA), were used to calibrate the analytical model to estimate each recharge component. The results demonstrated that periodic recharge estimates were most accurate in basins with nearly uniform transmissivity and the accuracy of the recharge estimates depends on monitoring well location. A case study of the San Pedro Basin, Arizona, is presented as an example of calibrating the analytical model to real data.

  5. Discrete-storm water-table fluctuation method to estimate episodic recharge.

    USGS Publications Warehouse

    Nimmo, John R.; Horowittz, Charles; Mitchell, Lara

    2015-01-01

    We have developed a method to identify and quantify recharge episodes, along with their associated infiltration-related inputs, by a consistent, systematic procedure. Our algorithm partitions a time series of water levels into discrete recharge episodes and intervals of no episodic recharge. It correlates each recharge episode with a specific interval of rainfall, so storm characteristics such as intensity and duration can be associated with the amount of recharge that results. To be useful in humid climates, the algorithm evaluates the separability of events, so that those whose recharge cannot be associated with a single storm can be appropriately lumped together. Elements of this method that are subject to subjectivity in the application of hydrologic judgment are values of lag time, fluctuation tolerance, and master recession parameters. Because these are determined once for a given site, they do not contribute subjective influences affecting episode-to-episode comparisons. By centralizing the elements requiring scientific judgment, our method facilitates such comparisons by keeping the most subjective elements openly apparent, making it easy to maintain consistency. If applied to a period of data long enough to include recharge episodes with broadly diverse characteristics, the method has value for predicting how climatic alterations in the distribution of storm intensities and seasonal duration may affect recharge.

  6. Estimation of recharge from irrigation flows; Analysis of field and laboratory data and modeling.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This work is aimed at quantifying aquifer recharge due to irrigation in the Campo de Cartagena (SE Spain). A study of recharge was conducted on an experiment plot cropped in lettuce and irrigated with a drip system. The physico-chemical and hydraulic properties of the vadose zone were characterized ...

  7. Discrete-storm water-table fluctuation method to estimate episodic recharge.

    PubMed

    Nimmo, John R; Horowitz, Charles; Mitchell, Lara

    2015-01-01

    We have developed a method to identify and quantify recharge episodes, along with their associated infiltration-related inputs, by a consistent, systematic procedure. Our algorithm partitions a time series of water levels into discrete recharge episodes and intervals of no episodic recharge. It correlates each recharge episode with a specific interval of rainfall, so storm characteristics such as intensity and duration can be associated with the amount of recharge that results. To be useful in humid climates, the algorithm evaluates the separability of events, so that those whose recharge cannot be associated with a single storm can be appropriately lumped together. Elements of this method that are subject to subjectivity in the application of hydrologic judgment are values of lag time, fluctuation tolerance, and master recession parameters. Because these are determined once for a given site, they do not contribute subjective influences affecting episode-to-episode comparisons. By centralizing the elements requiring scientific judgment, our method facilitates such comparisons by keeping the most subjective elements openly apparent, making it easy to maintain consistency. If applied to a period of data long enough to include recharge episodes with broadly diverse characteristics, the method has value for predicting how climatic alterations in the distribution of storm intensities and seasonal duration may affect recharge. PMID:24588378

  8. A ROOT ZONE MODELLING APPROACH TO ESTIMATING GROUNDWATER RECHARGE FROM IRRIGATED AREAS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In irrigated semi-arid and arid regions, accurate knowledge of groundwater recharge is important for the sustainable management of scarce water resources. The Campo de Cartagena area of southeast Spain is a semi-arid region where irrigation return flow accounts for a substantial portion of recharge....

  9. Recharge into Southern High Plains aquifer—possible mechanisms, unresolved questions

    NASA Astrophysics Data System (ADS)

    Nativ, Ronit

    1992-01-01

    The High Plains aquifer in the Southern High Plains (Texas and New Mexico), consisting of Tertiary, Cretaceous, and Triassic formations, has traditionally been considered to be recharged by its uppermost water-bearing unit, the Tertiary Ogallala aquifer. This article provides hydrologic, chemical, and isotopic evidence that in the Southern High Plains: (1) Cretaceous rocks actually contain independent recharge sources; (2) Triassic rocks cannot currently be recharged by the Ogallala aquifer in significant quantities; and (3) in places, both Cretaceous and Triassic aquifers recharge the overlying Ogallala aquifer. On the basis of chemical and isotopic data, playa lakes seem to act as the predominant recharge source of the Ogallala aquifer, suggesting recharge rates greater than 30 mm/yr, as opposed to the much lower rates reported by others. The Cretaceous aquifers are being recharged by cross-formational flow from the Ogallala aquifer but also from overlying Quaternary sands and the underlying Triassic aquifer in eastern New Mexico. Current recharge into the Triassic aquifer may be insignificant.

  10. Estimating recharge through Playa Lakes to the Southern High Plains Aquifer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the Southern High Plains of Texas, it is accepted that focused recharge to the High Plains Aquifer (locally known as the Ogallala) occurs through over 20,000 playa lakes, which are local depressions that collect storm runoff. The amount and rate of recharge is not precisely known, and the impact ...

  11. 78 FR 38093 - Thirteenth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-25

    ... Federal Aviation Administration Thirteenth Meeting: RTCA Special Committee 225, Rechargeable Lithium... Lithium Battery and Battery Systems--Small and Medium Size. SUMMARY: The FAA is issuing this notice to advise the public of the twelfth meeting of the RTCA Special Committee 225, Rechargeable Lithium...

  12. 78 FR 55773 - Fourteenth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-11

    ... Federal Aviation Administration Fourteenth Meeting: RTCA Special Committee 225, Rechargeable Lithium... Lithium Battery and Battery Systems--Small and Medium Size. SUMMARY: The FAA is issuing this notice to advise the public of the fourteenth meeting of the RTCA Special Committee 225, Rechargeable...

  13. 77 FR 39321 - Eighth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-02

    ... Federal Aviation Administration Eighth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery... Lithium Battery and Battery Systems--Small and Medium Sizes. SUMMARY: The FAA is issuing this notice to advise the public of the eighth meeting of RTCA Special Committee 225, Rechargeable Lithium Battery...

  14. 78 FR 16031 - Twelfth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-13

    ... Federal Aviation Administration Twelfth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery... Lithium Battery and Battery Systems--Small and Medium Size. SUMMARY: The FAA is issuing this notice to advise the public of the twelfth meeting of the RTCA Special Committee 225, Rechargeable Lithium...

  15. 78 FR 6845 - Eleventh Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-31

    ... Federal Aviation Administration Eleventh Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery... Lithium Battery and Battery Systems--Small and Medium Size. SUMMARY: The FAA is issuing this notice to advise the public of the eleventh meeting of the RTCA Special Committee 225, Rechargeable Lithium...

  16. PROSPECTS FOR ENHANCED GROUNDWATER RECHARGE VIA INFILTRATION OF URBAN STORMWATER RUNOFF: A CASE STUDY

    EPA Science Inventory

    The rain garden is an urban storm water best management practice that is used to infiltrate runoff close to its source, thereby disconnecting impervious area while providing an avenue for groundwater recharge. Groundwater recharge may provide additional benefits to aquatic ecosys...

  17. Influence of model conceptualisation on one-dimensional recharge quantification: Uley South, South Australia

    NASA Astrophysics Data System (ADS)

    Ordens, Carlos M.; Post, Vincent E. A.; Werner, Adrian D.; Hutson, John L.

    2014-06-01

    Model conceptualisation is a key source of uncertainty in one-dimensional recharge modelling. The effects of different conceptualisations on transient recharge predictions for the semi-arid Uley South Basin, South Australia, were investigated. One-dimensional unsaturated zone modelling was used to quantify the effect of variations of (1) lithological complexity of the unsaturated zone, and (2) representation of preferential flow pathways. The simulations considered ranges of water-table depths, vegetation characteristics, and top soil thicknesses representative for the study area. Complex lithological profiles were more sensitive to the selected vegetation characteristics and water-table depth. Scenarios considering runoff infiltration into, and preferential flow through sinkholes resulted in higher and faster recharge rates. A comparison of modelled and field-based recharge estimates indicated that: (1) the model simulated plausible recharge rates, (2) only the models with preferential flow correctly reproduced the timing of recharge, and (3) preferential flow is probably redistributed in the unsaturated zone rather than passing to the water table directly. Because different but equally plausible conceptual models produce widely varying recharge rates, field-based recharge estimates are essential to constrain the modelling results.

  18. Recharge Rates and Chemistry Beneath Playas of the High Plains Aquifer - A Literature Review and Synthesis

    USGS Publications Warehouse

    Gurdak, Jason J.; Roe, Cassia D.

    2009-01-01

    Playas are ephemeral, closed-basin wetlands that are important zones of recharge to the High Plains (or Ogallala) aquifer and critical habitat for birds and other wildlife in the otherwise semiarid, shortgrass prairie and agricultural landscape. The ephemeral nature of playas, low regional recharge rates, and a strong reliance on ground water from the High Plains aquifer has prompted many questions regarding the contribution of recharge from playas to the regional aquifer. To address these questions and concerns, the U.S. Geological Survey, in cooperation with the Playa Lakes Joint Venture, present a review and synthesis of the more than 175 publications about recharge rates and chemistry beneath playas and interplaya settings. Although a number of questions remain regarding the controls on recharge rates and chemistry beneath playas, the results from most published studies indicate that recharge rates beneath playas are substantially (1 to 2 orders of magnitude) higher than recharge rates beneath interplaya settings. The synthesis presented here supports the conceptual model that playas are important zones of recharge to the High Plains aquifer and are not strictly evaporative pans. The major findings of this synthesis yield science-based implications for the protection and management of playas and ground-water resources of the High Plains aquifer and directions for future research.

  19. Importance of unsaturated zone flow for simulating recharge in a humid climate

    USGS Publications Warehouse

    Hunt, R.J.; Prudic, D.E.; Walker, J.F.; Anderson, M.P.

    2008-01-01

    Transient recharge to the water table is often not well understood or quantified. Two approaches for simulating transient recharge in a ground water flow model were investigated using the Trout Lake watershed in north-central Wisconsin: (1) a traditional approach of adding recharge directly to the water table and (2) routing the same volume of water through an unsaturated zone column to the water table. Areas with thin (less than 1 m) unsaturated zones showed little difference in timing of recharge between the two approaches; when water was routed through the unsaturated zone, however, less recharge was delivered to the water table and more discharge occurred to the surface because recharge direction and magnitude changed when the water table rose to the land surface. Areas with a thick (15 to 26 m) unsaturated zone were characterized by multimonth lags between infiltration and recharge, and, in some cases, wetting fronts from precipitation events during the fall overtook and mixed with infiltration from the previous spring snowmelt. Thus, in thicker unsaturated zones, the volume of water infiltrated was properly simulated using the traditional approach, but the timing was different from simulations that included unsaturated zone flow. Routing of rejected recharge and ground water discharge at land surface to surface water features also provided a better simulation of the observed flow regime in a stream at the basin outlet. These results demonstrate that consideration of flow through the unsaturated zone may be important when simulating transient ground water flow in humid climates with shallow water tables.

  20. NUCLEAR-FUELED CIRCULATORY SUPPORT SYSTEMS IV: RADIOLOGIC PERSPECTIVES

    PubMed Central

    Huffman, F. N.; Norman, J. C.

    1974-01-01

    If an implantable artificial heart can be developed, it should prove beneficial to a significant group of patients. A variety of energy sources, such as biologic, electromagnetic, and nuclear, are under evaluation. Currently, biologic fuel cell technology is not sufficiently advanced to permit its extrapolation to the power levels required for implantable circulatory support systems. Electromagnetic systems have the disadvantage of heavy batteries of considerable bulk requiring frequent recharging. Radioisotope-fueled thermal engine systems have the potential of providing degrees of freedom not possible with rechargeable units. However, radiosotope circulatory support systems subject their recipients to prolonged intracorporeal radiation, add to environmental background radiation, and constitute an exceedingly small, but finite, hazard due to possible violation of fuel containment. PMID:15215965

  1. Climate Impact on Groundwater Recharge in Southeastern Louisiana and Southwestern Mississippi

    NASA Astrophysics Data System (ADS)

    Beigi, E.; Tsai, F. T.

    2012-12-01

    Increases of concentrations of CO2 and other greenhouse gases have a significant effect on global climate, precipitation and hydrology, which in turn influences recharge to aquifers. Groundwater recharge study is imperative to the sole source aquifer, for example the Southern Hills aquifer system in southeastern Louisiana and southwestern Mississippi, which provides more than 50 percent of the drinking water consumed in the area overlying the aquifer and has no substitute drinking water source(s). To trace the climate impact and its consequent groundwater availability, this study developed a GIS-based integrated framework to connect climate models to a high-resolution hydrologic model to quantify long-term groundwater recharge. We employed the Hydrologic Evaluation of Landfill Performance (HELP3) model as our hydrologic model to estimate spatial-temporal distribution of potential recharge for a regional scale. HELP3 model was especially suitable for our recharge study due to Louisiana humid climate and the use of a regional-scale water budget approach. Detailed surficial soil property and land cover were obtained from the NRCS and the USGS to derive maps of curve number for the HELP3 model. Wireline well logs and drillers logs were analyzed to determine stratigraphic lithology and the first major sand encountered beneath the soil layer. For a regional scale, we used global circulation model (GCM) downscaled daily precipitation and temperature obtained from USGS CASCaDE Project Climate Data as the forcing input to the HELP3 model. The emission scenarios considered in this study were A2, B1 and A1FI from Parallel Climate Model 1 (PCM) and from the NOAA Geophysical Fluid Dynamics Lab's GFDL CM2.1 model. We used the computed runoff from USGS WaterWatch along with the HELP3 model to calculate the recharge index (RI) and delineate the recharge index map for individual hydrologic units in terms of Hydrologic Unit Codes (HUCs). The recharge index was defined as the percentage of precipitation that recharges aquifers. High-resolution recharge index maps were obtained to quantify the spatial impact of climate change on long-term groundwater availability. The framework was applied to the recharge study on the Southern Hills aquifer system overlain by twenty HUCs. The RI map for the Southern Hill aquifer system was obtained based on the computed runoff data from 1951 to 2000 in WaterWatch. Then the HELP3 model was applied to recharge estimation from 2000 to 2050. The results showed the differences in recharge estimation given different climate scenarios. Moreover, the results showed spatial-temporal variation of recharge in the aquifer system due to variations in land use, soil characteristics and predicted meteorological variables.

  2. Spatio-temporal recharge patterns in a semi-arid alluvial basin with irrigated crops

    NASA Astrophysics Data System (ADS)

    Ruud, N. C.; Harter, T.; Naugle, A. W.

    2001-12-01

    Recharge in semi-arid regions with irrigated crops is predominantly driven by irrigation technology and cropping patterns, but also by the seasonal distribution of rainfall and the availability of irrigation water. A significant amount of basin recharge occurs from ephemeral streams and unlined irrigation canals. A spatially distributed, GIS-based hydrologic model of water application and water use at the land-atmosphere interface was developed to estimate transient recharge to the deep vadose zone and into the unconfined alluvial aquifer. The spatial basis for the hydrologic model are individual landuse units (diffuse recharge) and a network of streams and canals with water seepage (lineal recharge). The land-atmosphere interface and unsaturated zone model component (LAIUZ) is coupled to a surface water supply model component (SWSM) that provides surface water deliveries by district or sub-district, depending on available information. Using LAIUZ and SWSM, we investigate the regional behavior and spatio-temporal variability of deep vadose zone recharge in the 3,800 square kilometer Tule groundwater basin of the San Joaquin Valley, California. Surface water management in the topographically flat basin is divided between two dozen irrigation and water districts. All surface water is imported or is natural discharge into the basin. Groundwater extractions are managed by landowners on a field-by-field basis. Monthly varying recharge and groundwater pumping rates are computed for the hydrologic years 1970 through 2000. The average size of the GIS landuse units is 0.4 sq. kilometers. The GIS coverage distinguishes over 60 landuse types. Applied and consumptive water use are computed based on actual evapotranspiration and known irrigation or water use efficiencies for each landuse unit. Seepage from streams is computed by mass balance. The resulting model estimates of groundwater recharge and pumping are in good agreement with measured groundwater level changes for the thirty-year period (model validation). Throughout the region, the deep vadose zone (up to 30 m deep) is found to account for a significant amount of intermediate-term basin storage, particularly during wet year cycles. The hydrologic model demonstrates that practically all of the annual precipitation (230 mm) is available for intermediate storage in the root zone, crop water uptake, or deep percolation. No direct losses to evaporation occur, presumably because most precipitation occurs during the winter months. Diffuse recharge is 110 mm/year (range: 38 - 200 mm/year). Lineal recharge accounts for one-third of the total recharge (170 mm/year) in the basin. In wet years, lineal recharge along streams and in intentional recharge basins may account for over 50% of the total recharge, whereas in dry years it may be as little as 8%.

  3. Water-storage change measured with high-precision gravimetry at a groundwater recharge facility in Tucson, USA.

    NASA Astrophysics Data System (ADS)

    Creutzfeldt, B.; Kennedy, J.; Ferre, P. A.

    2012-12-01

    Groundwater depletion is a serious problem in many regions around the world. Artificial groundwater recharge is used for the short- and long-term storage of water in subsurface and can be an effective tool to prevent aquifer over-draft. Effective design and management of recharge facilities benefits from knowledge of the subsurface conditions and water-storage properties. In this study we combine different types of gravimeters and coupled hydrogeophysical inverse techniques to monitor subsurface water storage and to estimate subsurface hydraulic properties at the field scale. Water storage dynamics are continuously monitored with two iGrav™ superconducting gravimeters and three gPhones at three infiltration basins of the Tucson Water Southern Avra Valley Storage and Recovery Project facility. These continuous gravity observations are supported by time-lapse monitoring with absolute and spring gravimeters to map spatial gravity variations. Water level is monitored at 16 wells in the vicinity. The results of the first 6-month drying-wetting-drying cycle of the infiltration basins, during which 4,240,500 cubic meters (3,440 acre-feet) infiltrated over 53 days, are presented in this study. Gravity variations up to 170 μGal were observed. Collocated measurements show an overall good agreement of the different gravimeters. Distinct spatial variations of gravity change indicate variable water storage dynamics caused by subsurface heterogeneity at the field scale. Multiple gravimeter types combined with coupled inversion allows accurate tracking of subsurface water storage, which can improve the predictions of subsurface conditions and the water resources management of artificial recharge facilities.

  4. Selection Site for Artificial Recharge of Groundwater in Hard Rocks Using ANN with Special Reference to India

    NASA Astrophysics Data System (ADS)

    Banerjee, Pallavi

    2010-05-01

    In the recent years there has been overall development in the field of agriculture and industry in the Asian countries, particularly in India. The growth in urbanization has also been increasing. All these have lead to ever increasing demand for water. It has resulted into indiscriminate exploitation of groundwater resources, which is major source of fresh water in hard rock terrain. The hard rocks pose special problems for artificial recharge due to the limited extent of aquifer horizons, heterogeneity and low hydraulic conductivity. The fracture system may have good storativity. One such area is Kurmapalli watershed covering an area of about 108 sq km in Nalgonda district (Andhra Pradesh), India. It is drought prone area. This basin is characterized by poor land soil, scarce vegetation, erratic rainfall, heavy runoff and lack of soil moisture for most part of the year. Recurring drought coupled with increase in groundwater exploitation results in decline in the groundwater levels. Artificial Neural Network (ANN) method is a paradigm shift towards research methodology in the field of hydrology. An approach based on Back Propagation Neural Network (BPNN) algorithm is developed to estimate the best location for artificial recharge. The proposed technique is applied to climatic and hydrological data of wells gathered from the different locations of the study area. Feed Forward BPNN is used to train the predefined inputs and outputs. After successful completion of training with appropriate data, different ANN models are developed to estimate the proper site for artificial recharge. High degree of predictive accuracy of the Feed-Forward Network based predictive model proves ANN techniques is a potential tool for hydrological studies.

  5. Identification of potential artificial groundwater recharge zones in Northwestern Saudi Arabia using GIS and Boolean logic

    NASA Astrophysics Data System (ADS)

    Zaidi, Faisal K.; Nazzal, Yousef; Ahmed, Izrar; Naeem, Muhammad; Jafri, Muhammad Kamran

    2015-11-01

    Identifying potential groundwater recharge zones is a pre-requisite for any artificial recharge project. The present study focuses on identifying the potential zones of Artificial Groundwater Recharge (AGR) in Northwestern Saudi Arabia. Parameters including slope, soil texture, vadose zone thickness, groundwater quality (TDS) and type of water bearing formation were integrated in a GIS environment using Boolean logic. The results showed that 17.90% of the total studied area is suitable for AGR. The identified zones were integrated with the land use/land cover map to avoid agricultural and inhabited lands which reduced the total potential area to 14.24%. Geomorphologically the wadi beds are the most suitable sites for recharge. On the basis of the potential AGR zones closeness to the available recharge water supply (rain water, desalinated sea water and treated waste water) the potential zones were classified as Category A (high priority) and Category B (low priority).

  6. 3H and 14C as tracers of ground-water recharge

    USGS Publications Warehouse

    Izbicki, John A.; Michel, Robert L.; Martin, Peter

    1992-01-01

    Surface spreading of water from the Santa Clara River is used to recharge aquifers underlying the Oxnard Plain. These aquifers are divided into an upper system about 400 feet thick, and a lower system more than 1,000 feet thick. In previous studies, it has been reported that surface spreading recharged aquifers in both the upper and lower systems. Water from most wells perforated in the upper system has tritium levels consistent with decay-corrected concentrations found in water recharged after 1952 when tritium levels increased as a result of atmospheric testing of nuclear weapons. Water from most wells in the lower system does not contain measurable tritium and must have been recharged prior to 1952. Carbon-14 ages estimated for water from wells in the lower system range from recent to about 25,000 years before present. These data show that the lower system is not effectively recharged by surface spreading.

  7. Pathogen Decay during Managed Aquifer Recharge at Four Sites with Different Geochemical Characteristics and Recharge Water Sources.

    PubMed

    Sidhu, J P S; Toze, S; Hodgers, L; Barry, K; Page, D; Li, Y; Dillon, P

    2015-09-01

    Recycling of stormwater water and treated effluent via managed aquifer recharge (MAR) has often been hampered because of perceptions of low microbiological quality of recovered water and associated health risks. The goal of this study was to assess the removal of selected pathogens in four large-scale MAR schemes and to determine the influence of aquifer characteristics, geochemistry, and type of recharge water on the pathogen survival times. Bacterial pathogens tested in this study had the shortest one log removal time (, <3 d), followed by oocysts (, <120 d), with enteric viruses having the biggest variability in removal times (, 18 to >200 d). Human adenovirus and rotavirus were relatively persistent under anaerobic conditions (, >200 d). Human adenovirus survived longer than all the other enteric virus tested in the study and hence could be used as a conservative indicator for virus removal in groundwater during MAR. The results suggest that site-specific subsurface conditions such as groundwater chemistry can have considerable influence on the decay rates of enteric pathogens and that viruses are likely to be the critical pathogens from a public health perspective. PMID:26436258

  8. Alternative Fuels Infrastructure Development

    SciTech Connect

    Bloyd, Cary N.; Stork, Kevin

    2011-02-01

    This summary reviews the status of alternate transportation fuels development and utilization in Thailand. Thailand has continued to work to promote increased consumption of gasohol especially for highethanol content fuels like E85. The government has confirmed its effort to draw up incentives for auto makers to invest in manufacturing E85-compatible vehicles in the country. An understanding of the issues and experiences associated with the introduction of alternative fuels in other countries can help the US in anticipation potential problems as it introduces new automotive fuels.

  9. Opportunity fuels

    SciTech Connect

    Lutwen, R.C.

    1994-12-31

    Opportunity fuels - fuels that can be converted to other forms of energy at lower cost than standard fossil fuels - are discussed in outline form. The type and source of fuels, types of fuels, combustability, methods of combustion, refinery wastes, petroleum coke, garbage fuels, wood wastes, tires, and economics are discussed.

  10. Chloride-mass-balance for predicting increased recharge after land-use change

    SciTech Connect

    Gee, G.W.; Zhang, Z.F.; Tyler, S.W.; Albright, W.H.; Singleton, M.J.

    2004-02-23

    The chloride-mass-balance (CMB) method has been used extensively to estimate recharge in arid and semi-arid environments. Required data include estimates of annual precipitation, total chloride input (from dry fallout and precipitation), and pore-water chloride concentrations. Typically, CMB has been used to estimate ancient recharge but recharge from recent land-use change has also been documented. Recharge rates below a few mm/yr are reliably detected with CMB; however, estimates above a few mm/yr appear to be less reliable. We tested the CMB method against 26 years of drainage from a 7.6-m-deep lysimeter at a simulated waste-burial ground, located on the Department of Energy s Hanford Site in southeastern Washington State, USA where land-use change has increased recharge rates. Measured drainage from the lysimeter for the past 26 years averaged 62 mm/yr. Precipitation averaged 190 mm/yr with an estimated chloride input of 0.225 mg/L. Initial pore-water chloride concentration was 88 mg/L and decreased to about 6 mg/L after 26 years, while the drainage water decreased to less than 1 mg/L. A recharge estimate made using chloride concentrations in drain water was within 20 percent of the measured drainage rate. In contrast, recharge estimates using 1:1 (water: soil) extracts were lower than actual by factors ranging from 2 to 8 or more. The results suggest that when recharge is above a few mm/yr, soil water extracts can lead to unreliable estimates of recharge. For conditions of elevated recharge, direct sampling of pore water is the preferred method, because chloride concentrations are often 20 to 50 times higher in directly-sampled pore water than in pore-water extracts.

  11. Spatial and temporal variability of ground water recharge in central Australia: a tracer approach.

    PubMed

    Harrington, Glenn A; Cook, Peter G; Herczeg, Andrew L

    2002-01-01

    Two environmental tracer methods are applied to the Ti-Tree Basin in central Australia to shed light on the importance of recharge from floodouts of ephemeral rivers in this arid environment. Ground water carbon-14 concentrations from boreholes are used to estimate the average recharge rate over the interval between where the ground water sample first entered the saturated zone and the bore. Environmental chloride concentrations in ground water samples provide estimates of the recharge rate at the exact point in the landscape where the sample entered the saturated zone. The results of the two tracer approaches indicate that recharge rates around one of the rivers and an extensive floodplain are generally higher than rates of diffuse recharge that occurs in areas of lower topographic relief. Ground water 2H/1H and 18O/16O compositions are all depleted in the heavier isotopes (delta2H = -67 per thousand to -50 per thousand; delta18O = -9.2 per thousand to -5.7%o) compared with the long-term, amount-weighted mean isotopic composition of rainfall in the area (delta2H = -33.8 per thousand; delta18O = -6.3 per thousand). This indicates that recharge throughout the basin occurs only after intense rainfall events of at least 150 to 200 mm/month. Finally, a recharge map is developed to highlight the spatial extent of the two recharge mechanisms. Floodout recharge to the freshest ground water (TDS <1,000 mg/L) is approximately 1.9 mm/year compared with a mean recharge rate of approximately 0.2 mm/year to the remainder of the basin. These findings have important implications for management of the ground water resource. PMID:12236265

  12. Temporal and spatial variability of groundwater recharge on Jeju Island, Korea

    USGS Publications Warehouse

    Mair, Alan; Hagedorn, Benjamin; Tillery, Suzanne; El-Kadi, Aly I.; Westenbroek, Stephen; Ha, Kyoochul; Koh, Gi-Won

    2013-01-01

    Estimates of groundwater recharge spatial and temporal variability are essential inputs to groundwater flow models that are used to test groundwater availability under different management and climate conditions. In this study, a soil water balance analysis was conducted to estimate groundwater recharge on the island of Jeju, Korea, for baseline, drought, and climate-land use change scenarios. The Soil Water Balance (SWB) computer code was used to compute groundwater recharge and other water balance components at a daily time step using a 100 m grid cell size for an 18-year baseline scenario (1992–2009). A 10-year drought scenario was selected from historical precipitation trends (1961–2009), while the climate-land use change scenario was developed using late 21st century climate projections and a change in urban land use. Mean annual recharge under the baseline, drought, and climate-land use scenarios was estimated at 884, 591, and 788 mm, respectively. Under the baseline scenario, mean annual recharge was within the range of previous estimates (825–959 mm) and only slightly lower than the mean of 902 mm. As a fraction of mean annual rainfall, mean annual recharge was computed as only 42% and less than previous estimates of 44–48%. The maximum historical reported annual pumping rate of 241 × 106 m3 equates to 15% of baseline recharge, which is within the range of 14–16% computed from earlier studies. The model does not include a mechanism to account for additional sources of groundwater recharge, such as fog drip, irrigation, and artificial recharge, and may also overestimate evapotranspiration losses. Consequently, the results presented in this study represent a conservative estimate of total recharge.

  13. Data-Conditioned Distributions of Groundwater Recharge Under Climate Change Scenarios

    NASA Astrophysics Data System (ADS)

    McLaughlin, D.; Ng, G. C.; Entekhabi, D.; Scanlon, B.

    2008-12-01

    Groundwater recharge is likely to be impacted by climate change, with changes in precipitation amounts altering moisture availability and changes in temperature affecting evaporative demand. This could have major implications for sustainable aquifer pumping rates and contaminant transport into groundwater reservoirs in the future, thus making predictions of recharge under climate change very important. Unfortunately, in dry environments where groundwater resources are often most critical, low recharge rates are difficult to resolve due to high sensitivity to modeling and input errors. Some recent studies on climate change and groundwater have considered recharge using a suite of general circulation model (GCM) weather predictions, an obvious and key source of uncertainty. This work extends beyond those efforts by also accounting for uncertainty in other land-surface model inputs in a probabilistic manner. Recharge predictions are made using a range of GCM projections for a rain-fed cotton site in the semi-arid Southern High Plains region of Texas. Results showed that model simulations using a range of unconstrained literature-based parameter values produce highly uncertain and often misleading recharge rates. Thus, distributional recharge predictions are found using soil and vegetation parameters conditioned on current unsaturated zone soil moisture and chloride concentration observations; assimilation of observations is carried out with an ensemble importance sampling method. Our findings show that the predicted distribution shapes can differ for the various GCM conditions considered, underscoring the importance of probabilistic analysis over deterministic simulations. The recharge predictions indicate that the temporal distribution (over seasons and rain events) of climate change will be particularly critical for groundwater impacts. Overall, changes in recharge amounts and intensity were often more pronounced than changes in annual precipitation and temperature, thus suggesting high susceptibility of groundwater systems to future climate change. Our approach provides a probabilistic sensitivity analysis of recharge under potential climate changes, which will be critical for future management of water resources.

  14. Comparison of local- to regional-scale estimates of ground-water recharge in Minnesota, USA

    USGS Publications Warehouse

    Delin, G.N.; Healy, R.W.; Lorenz, D.L.; Nimmo, J.R.

    2007-01-01

    Regional ground-water recharge estimates for Minnesota were compared to estimates made on the basis of four local- and basin-scale methods. Three local-scale methods (unsaturated-zone water balance, water-table fluctuations (WTF) using three approaches, and age dating of ground water) yielded point estimates of recharge that represent spatial scales from about 1 to about 1000 m2. A fourth method (RORA, a basin-scale analysis of streamflow records using a recession-curve-displacement technique) yielded recharge estimates at a scale of 10–1000s of km2. The RORA basin-scale recharge estimates were regionalized to estimate recharge for the entire State of Minnesota on the basis of a regional regression recharge (RRR) model that also incorporated soil and climate data. Recharge rates estimated by the RRR model compared favorably to the local and basin-scale recharge estimates. RRR estimates at study locations were about 41% less on average than the unsaturated-zone water-balance estimates, ranged from 44% greater to 12% less than estimates that were based on the three WTF approaches, were about 4% less than the age dating of ground-water estimates, and were about 5% greater than the RORA estimates. Of the methods used in this study, the WTF method is the simplest and easiest to apply. Recharge estimates made on the basis of the UZWB method were inconsistent with the results from the other methods. Recharge estimates using the RRR model could be a good source of input for regional ground-water flow models; RRR model results currently are being applied for this purpose in USGS studies elsewhere.

  15. Impacts of thickening unsaturated zone on groundwater recharge in the North China Plain

    NASA Astrophysics Data System (ADS)

    Cao, Guoliang; Scanlon, Bridget R.; Han, Dongmei; Zheng, Chunmiao

    2016-06-01

    Unsustainable groundwater development shown by rapid groundwater depletion in the North China Plain (NCP) underscores the need to quantify spatiotemporal variability in groundwater recharge for improved management of the resource. The objective of this study was to assess spatiotemporal variability in recharge in response to thickening of the unsaturated zone in the NCP. Recharge was estimated by linking a soil water balance (SWB) model, on the basis of monthly meteorological data, irrigation applications, and soil moisture monitoring data (1993-2008), to the water table using a deep unsaturated zone flow model. The dynamic bottom boundary (water table) position was provided by the saturated zone flow component, which simulates regional pumping. The model results clearly indicate the effects of unsaturated zone thickening on both temporal distribution and magnitude of recharge: smoothing temporal variability in recharge, and increasing unsaturated storage and lag time between percolation and recharge. The thickening unsaturated zone can result in average recharge reduction of up to ∼70% in loam soils with water table declines ⩾30 m. Declining groundwater levels with irrigation sourced by groundwater converts percolation to unsaturated zone storage, averaging 14 mm equivalent water depth per year in mostly loam soil over the study period, accounting for ∼30% of the saturated groundwater storage depletion. This study demonstrates that, in thickening unsaturated zones, modeling approaches that directly equate deep drainage with recharge will overestimate the amount and underestimate the time lag between percolation and recharge, emphasizing the importance of more realistic simulation of the continuity of unsaturated and saturated storage to provide more reliable estimates of spatiotemporal variability in recharge.

  16. Jet Fuel Thermal Stability

    NASA Technical Reports Server (NTRS)

    Taylor, W. F. (Editor)

    1979-01-01

    Various aspects of the thermal stability problem associated with the use of broadened-specification and nonpetroleum-derived turbine fuels are addressed. The state of the art is reviewed and the status of the research being conducted at various laboratories is presented. Discussions among representatives from universities, refineries, engine and airframe manufacturers, airlines, the Government, and others are presented along with conclusions and both broad and specific recommendations for future stability research and development. It is concluded that significant additional effort is required to cope with the fuel stability problems which will be associated with the potentially poorer quality fuels of the future such as broadened specification petroleum fuels or fuels produced from synthetic sources.

  17. Climate Change Effects on Groundwater Recharge East of Yucca Mountain

    NASA Astrophysics Data System (ADS)

    Woocay, A.; Walton, J. C.

    2007-12-01

    In order to better understand the general flow system and climate-induced changes in recharge around Fortymile Wash, near Yucca Mountain, groundwater geochemical data from the Amargosa Desert region were analyzed. Also, chloride mass balance (CMB) was applied to drill cuttings from borehole NC-EWDP-22S near Fortymile Wash. Stable isotopic hydrogen-2 and oxygen-18 data indicate that less depleted groundwater is found under the flowpath of Fortymile Wash compared with groundwater perpendicular to the wash, and in the lower end of the wash compared with the source in the canyon. In addition, water isotope data under Fortymile Wash plot below the global meteoric water line (GMWL), suggesting low evaporation before infiltration. Total dissolved solids (TDS) and chloride (Cl) concentrations are lowest in the groundwater along the wash indicating less rock/water interaction and low evaporation prior to infiltration. In consequence, stable isotope, TDS and Cl data are most consistent with a pattern of infiltration and recharge of surface runoff subsequent to runoff-generating storms. Carbon-14 data corrected with carbon-13 data presents ages between 8,000 years before present (BP) in the upper canyon region and 14,000 years BP in the lower region near the Amargosa Desert. This range in ages corresponds to the end of the Pleistocene and early Holocene epochs. In contrast, groundwater adjacent to Fortymile Wash appears to be older than that beneath the wash. Furthermore, the trend of groundwater age increase and further stable isotope depletion beneath Fortymile Wash with increasing distance from the canyon suggests that the average reach of recharge and runoff events diminished over time as the climate became warmer and dryer. CMB results present two different pore velocities, the slower one nearer to the surface and with the transition occurring between 6 and 26 meters in depth corresponding to 8,5000 and 11,000 BP. Considered together, these facts suggest that ground water under Fortymile Wash is not derived primarily from migration of adjacent ground water, as indicated by coarse contoured water levels, but instead from past focused infiltration that diminished due to a changing climate.

  18. Use of Constructed Wetlands for Polishing Recharge Wastewater

    NASA Astrophysics Data System (ADS)

    Cardwell, W.

    2009-12-01

    The use of constructed wetlands for waste water treatment is becoming increasingly popular as more focus is being shifted to natural means of waste treatment. These wetlands employ processes that occur naturally and effectively remove pollutants and can greatly minimize costs when compared to full scale treatment plants. Currently, wetland design is based on basic “rules-of-thumb,” meaning engineers have a general understanding but not necessarily a thorough knowledge of the intricate physical, biological, and chemical processes involved in these systems. Furthermore, there is very little consideration given to use the wetland as a recharge pond to allow the treated water to percolate and recharge the local groundwater aquifers. The City of Foley, located in Alabama, and the Utilities Board of the City of Foley partnered with Wolf Bay Watershed Watch to evaluate alternative wastewater effluent disposal schemes. Rather than discharging the treated water into a local stream, a pilot program has been developed to allow water from the treatment process to flow into a constructed wetlands area where, after natural treatment, the treated water will then be allowed to percolate into a local unconfined aquifer. The goal of this study is to evaluate how constructed wetlands can be used for “polishing” effluent as well as how this treated water might be reused. Research has shown that constructed wetlands, with proper design and construction elements, are effective in the treatment of BOD, TSS, nitrogen, phosphorous, pathogens, metals, sulfates, organics, and other substances commonly found in wastewater. Mesocosms will be used to model the wetland, at a much smaller scale, in order to test and collect data about the wetland treatment capabilities. Specific objectives include: 1. Determine optimum flow rates for surface flow wetlands where water treatment is optimized. 2. Evaluate the capabilities of constructed wetlands to remove/reduce common over the counter pharmaceuticals such as acetaminophen (Tylenol) and ibuprofen. 3. Evaluate the use of different wetland plants and their treatment characteristics. 4. Evaluate the effectiveness of the wetlands to allow treated to water to recharge local into a local groundwater aquifer.

  19. Zeolite in horizontal permeable reactive barriers for artificial groundwater recharge

    NASA Astrophysics Data System (ADS)

    Leal, María; Martínez-Hernández, Virtudes; Lillo, Javier; Meffe, Raffaella; de Bustamante, Irene

    2013-04-01

    The Spanish Water Reuse Royal Decree 1620/2007 considers groundwater recharge as a feasible use of reclaimed water. To achieve the water quality established in the above-mentioned legislation, a tertiary wastewater treatment is required. In this context, the infiltration of effluents generated by secondary wastewater treatments through a Horizontal Permeable Reactive Barrier (HPRB) may represent a suitable regeneration technology. Some nutrients (phosphate and ammonium) and some Pharmaceutical and Personal Care Products (PPCPs) are not fully removed in conventional wastewater treatment plants. To avoid groundwater contamination when effluents of wastewater treatments plants are used in artificial recharge activities, these contaminants have to be removed. Due to its sorption capacities, zeolite is among the most used reactive materials in Permeable Reactive Barrier (PRB). Therefore, the main goal of this study is to evaluate the zeolite retention effectiveness of nutrients and PPCPs occurring in treated wastewater. Batch sorption experiments using synthetic wastewater (SWW) and zeolite were performed. A 1:4 zeolite/SWW ratio was selected due to the high sorption capacity of the reactive material.The assays were carried out by triplicate. All the bottles containing the SWW-zeolite mixture were placed on a mechanical shaker during 24 hours at 140 rpm and 25 °C. Ammonium and phosphate, as main nutrients, and a group of PPCPs were selected as compounds to be tested during the experiments. Nutrients were analyzed by ion chromatography. For PPCPs determination, Solid Phase Extraction (SPE) was applied before their analysis by liquid chromatography-mass spectrometry time of flight (LC-MS/ TOF). The experimental data were fitted to linearized Langmuir and Freundlich isotherm equations to obtain sorption parameters. In general, Freundlich model shows a greater capability of reproducing experimental data. To our knowledge, sorption of the investigated compounds on zeolite has rarely been addressed and this holds true especially for PPCPs. Therefore, the obtained results will be useful for the design and characterization of those HPRBs in which zeolite will be employed to regenerate treated wastewater for artificial recharge activities.

  20. Lithologic influences on groundwater recharge through incised glacial till from profile to regional scales: Evidence from glaciated Eastern Nebraska

    NASA Astrophysics Data System (ADS)

    Gates, John B.; Steele, Gregory V.; Nasta, Paolo; Szilagyi, Jozsef

    2014-01-01

    Variability in sediment hydraulic properties associated with landscape depositional and erosional features can influence groundwater recharge processes by affecting soil-water storage and transmission. This study considers recharge to aquifers underlying river-incised glaciated terrain where the distribution of clay-rich till is largely intact in upland locations but has been removed by alluvial erosion in stream valleys. In a stream-dissected glacial region in eastern Nebraska (Great Plains region of the United States), recharge estimates were developed for nested profile, aquifer, and regional scales using unsaturated zone profile measurements (matric potentials, Cl- and 3H), groundwater tracers (CFC-12 and SF6), and a remote sensing-assisted water balance model. Results show a consistent influence of till lithology on recharge rates across nested spatial scales despite substantial uncertainty in all recharge estimation methods, suggesting that minimal diffuse recharge occurs through upland glacial till lithology whereas diffuse recharge occurs in river valleys where till is locally absent. Diffuse recharge is estimated to account for a maximum of 61% of total recharge based on comparison of diffuse recharge estimated from the unsaturated zone (0-43 mm yr-1) and total recharge estimated from groundwater tracers (median 58 mm yr-1) and water balance modeling (median 56 mm yr-1). The results underscore the importance of lithologic controls on the distributions of both recharge rates and mechanisms.

  1. The TMI regenerable solid oxide fuel cell

    NASA Technical Reports Server (NTRS)

    Cable, Thomas L.

    1995-01-01

    Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. These systems generally consist of photovoltaic solar arrays which operate during sunlight cycles to provide system power and regenerate fuel (hydrogen) via water electrolysis; during dark cycles, hydrogen is converted by the fuel cell into system. The currently preferred configuration uses two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Fuel cell/electrolyzer system simplicity, reliability, and power-to-weight and power-to-volume ratios could be greatly improved if both power production (fuel cell) and power storage (electrolysis) functions can be integrated into a single unit. The Technology Management, Inc. (TMI), solid oxide fuel cell-based system offers the opportunity to both integrate fuel cell and electrolyzer functions into one unit and potentially simplify system requirements. Based an the TMI solid oxide fuel cell (SOPC) technology, the TMI integrated fuel cell/electrolyzer utilizes innovative gas storage and operational concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H2O electrode (SOFC anode/electrolyzer cathode) materials for solid oxide, regenerative fuel cells. Improved H2/H2O electrode materials showed improved cell performance in both fuel cell and electrolysis modes in reversible cell tests. ln reversible fuel cell/electrolyzer mode, regenerative fuel cell efficiencies (ratio of power out (fuel cell mode) to power in (electrolyzer model)) improved from 50 percent (using conventional electrode materials) to over 80 percent. The new materials will allow the TMI SOFC system to operate as both the electrolyzer and fuel cell in a single unit. Preliminary system designs have also been developed which indicate the technical feasibility of using the TMI SOFC technology for space applications with high energy storage efficiencies and high specific energy. Development of small space systems would also have potential dual-use, terrestrial applications.

  2. Fuel performance annual report for 1983. Volume 1

    SciTech Connect

    Bailey, W.J.; Dunenfeld, M.S.

    1985-03-01

    This annual report, the sixth in a series, provides a brief description of fuel performance during 1983 in commercial nuclear power plants. Brief summaries of fuel design changes, fuel surveillance programs, fuel operating experience, fuel problems, high-burnup fuel experience, and items of general significance are provided. References to additional, more detailed information and related NRC evaluations are included.

  3. Fuel performance annual report for 1981. [PWR; BWR

    SciTech Connect

    Bailey, W.J.; Tokar, M.

    1982-12-01

    This annual report, the fourth in a series, provides a brief description of fuel performance during 1981 in commercial nuclear power plants. Brief summaries of fuel operating experience, fuel problems, fuel design changes and fuel surveillance programs, and high-burnup fuel experience are provided. References to additional, more detailed information and related NRC evaluations are included.

  4. Fuel performance annual report for 1990. Volume 8

    SciTech Connect

    Preble, E.A.; Painter, C.L.; Alvis, J.A.; Berting, F.M.; Beyer, C.E.; Payne, G.A.; Wu, S.L.

    1993-11-01

    This annual report, the thirteenth in a series, provides a brief description of fuel performance during 1990 in commercial nuclear power plants. Brief summaries of fuel design changes, fuel surveillance programs, fuel operating experience and trends, fuel problems high-burnup fuel experience, and items of general significance are provided . References to additional, more detailed information, and related NRC evaluations are included where appropriate.

  5. Alcohol Transportation Fuels Demonstration Program

    SciTech Connect

    Kinoshita, C.M.

    1990-01-01

    Hawaii has abundant natural energy resources, especially biomass, that could be used to produce alternative fuels for ground transportation and electricity. This report summarizes activities performed during 1988 to June 1991 in the first phase of the Alcohol Transportation Fuels Demonstration Program. The Alcohol Transportation Fuels Demonstration Program was funded initially by the Energy Division of the State of Hawaii's Department of Business, Economic Development and Tourism, and then by the US Department of Energy. This program was intended to support the transition to an altemative transportation fuel, methanol, by demonstrating the use of methanol fuel and methanol-fueled vehicles, and solving the problems associated with that fuel. Specific objectives include surveying renewable energy resources and ground transportation in Hawaii; installing a model methanol fueling station; demonstrating a methanol-fueled fleet of (spark-ignition engine) vehicles; evaluating modification strategies for methanol-fueled diesel engines and fuel additives; and investigating the transition to methanol fueling. All major objectives of Phase I were met (survey of local renewable resources and ground transportation, installation of methanol refueling station, fleet demonstration, diesel engine modification and additive evaluation, and dissemination of information on alternative fueling), and some specific problems (e.g., relating to methanol fuel contamination during handling and refueling) were identified and solved. Several key issues emerging from Phase I (e.g., methanol corrosion, flame luminosity, and methanol-transition technoeconomics) were recommended as topics for follow-on research in subsequent phases of this program.

  6. Fuel performance annual report for 1986

    SciTech Connect

    Bailey, W.J.; Wu, S.

    1988-03-01

    This annual report, the ninth in a series, provides a brief description of fuel performance during 1986 in commercial nuclear power plants and an indication of trends. Brief summaries of fuel design changes, fuel surveillance programs, fuel operating experience, fuel problems, high-burnup fuel experience, and items of general significance are provided. References to more detailed information and related U.S. Nuclear Regulatory Commission evaluations are included. 550 refs., 12 figs., 31 tabs.

  7. Fuel performance annual report for 1985

    SciTech Connect

    Bailey, W.J.; Wu, S.

    1987-02-01

    This annual report, the eighth in a series, provides a brief description of fuel performance during 1985 in commercial nuclear power plants and an indication of trends. Brief summaries of fuel design changes, fuel surveillance programs, fuel operating experience, fuel problems, high-burnup fuel experience, and items of general significance are provided. References to additional, more detailed information and related NRC evaluations are included.

  8. Fuel performance annual report for 1989

    SciTech Connect

    Bailey, W.J.; Berting, F.M. ); Wu, S. . Div. of Systems Technology)

    1992-06-01

    This annual report, the twelfth in a series, provides a brief description of fuel performance during 1989 in commercial nuclear power plants and an indication of trends. Brief summaries of fuel design changes, fuel surveillance programs, fuel operating experience, fuel problems, high-burnup fuel experience, and items of general significance are provided. References to more detailed information and related US Nuclear Regulatory Commission evaluations are included.

  9. Fuel performance annual report for 1988

    SciTech Connect

    Bailey, W.J. ); Wu, S. . Div. of Engineering and Systems Technology)

    1990-03-01

    This annual report, the eleventh in a series, provides a brief description of fuel performance during 1988 in commercial nuclear power plants and an indication of trends. Brief summaries of fuel design changes, fuel surveillance programs, fuel operating experience, fuel problems, high-burnup fuel experience, and items of general significance are provided. References to more detailed information and related US Nuclear Regulatory Commission evaluations are included. 414 refs., 13 figs., 32 tabs.

  10. Fuel performance: Annual report for 1987

    SciTech Connect

    Bailey, W.J.; Wu, S.

    1989-03-01

    This annual report, the tenth in a series, provides a brief description of fuel performance during 1987 in commercial nuclear power plants and an indication of trends. Brief summaries of fuel design changes, fuel surveillance programs, fuel operating experience, fuel problems, high-burnup fuel experience, and items of general significance are provided. References to more detailed information and related US Nuclear Regulator Commission evaluations are included. 384 refs., 13 figs., 33 tabs.

  11. Hybrid systems with lead-acid battery and proton-exchange membrane fuel cell

    NASA Astrophysics Data System (ADS)

    Jossen, Andreas; Garche, Juergen; Doering, Harry; Goetz, Markus; Knaupp, Werner; Joerissen, Ludwig

    Hybrid systems, based on a lead-acid battery and a proton-exchange membrane fuel cell (PEMFC) give the possibility to combine the advantages of both technologies. The benefits for different applications are discussed and the practical realisation of such systems is shown. Furthermore a numerical model for such a hybrid system is described and results are shown and discussed. The results show that the combination of lead-acid batteries and PEMFC shows advantages in case of applications with high peak power requirements (i.e. electric scooter) and applications where the fuel cell is used as auxiliary power supply to recharge the battery. The high efficiency of fuel cells at partial load operation results in a good fuel economy for recharging of lead-acid batteries with a fuel cell system.

  12. Overcharge protection for rechargeable lithium polymer electrolyte batteries

    SciTech Connect

    Richardson, T.J.; Ross, P.N. Jr.

    1996-12-01

    Overcharge protection for rechargeable lithium polymer electrolyte cells by addition of redox shuttle additives to the polymer electrolyte was examined. Shuttle onset potentials and effective diffusion coefficients were determined for 12 redox shuttle species in polyethylene oxide-based electrolytes at 85 C. The four most promising additives were tested in Li/PEO-LiN(SO{sub 2}CF{sub 3}){sub 2}/Li{sub 2+x}Mn{sub 4}O{sub 9} cells under normal and severe overcharging conditions. In addition to tricyanobenzene and tetracyanoquinodimethane, two anionic redox shuttle additives, salts of 1,2,4-triazole and imidazole, demonstrated effectiveness in extending cycle life and good compatibility with cell components.

  13. Rechargeable cells with modified MnO2 cathodes

    NASA Astrophysics Data System (ADS)

    Dzieciuch, M. A.; Gupta, N.; Wroblowa, H. S.

    1988-10-01

    The recent invention of rechargeable 'modified' manganese oxide materials paves the way to the development of secondary batteries suitable for numerous applications. This includes alternatives to primary dry cells, and secondary lead/acid and nickel-cadmium batteries. Present results describe the performance of cells in which the modified materials are coupled with zinc and iron. As opposed to iron which does not affect the longevity and capacity retention of the modified electrodes, zinc has a pejorative effect on modified MnO2 materials, owing to the formation of heterolite at the positive electrode. Methods to alleviate this effect and produce viable modified MnO2/Zn systems are described. At present, these systems retain about 50 percent of their theoretical one-electron capacity even after two hundred fast charge-discharge cycles.

  14. Downstream of downtown: urban wastewater as groundwater recharge

    NASA Astrophysics Data System (ADS)

    Foster, S. S. D.; Chilton, P. J.

    Wastewater infiltration is often a major component of overall recharge to aquifers around urban areas, especially in more arid climates. Despite this, such recharge still represents only an incidental (or even accidental) byproduct of various current practices of sewage effluent handling and wastewater reuse. This topic is reviewed through reference to certain areas of detailed field research, with pragmatic approaches being identified to reduce the groundwater pollution hazard of these practices whilst attempting to retain their groundwater resource benefit. Since urban sewage effluent is probably the only `natural resource' whose global availability is steadily increasing, the socioeconomic importance of this topic for rapidly developing urban centres in the more arid parts of Asia, Africa, Latin America and the Middle East will be apparent. L'infiltration des eaux usées est souvent la composante essentielle de toute la recharge des aquifères des zones urbaines, particulièrement sous les climats les plus arides. Malgré cela, une telle recharge ne constitue encore qu'un sous-produit incident, ou même accidentel, de pratiques courantes variées du traitement de rejets d'égouts et de réutilisation d'eaux usées. Ce sujet est passé en revue en se référant à certaines régions étudiées en détail, par des approches pragmatiques reconnues pour permettre de réduire les risques de pollution des nappes dues à ces pratiques tout en permettant d'en tirer profit pour leur ressource en eau souterraine. Puisque les effluents d'égouts urbains sont probablement la seule « ressource naturelle » dont la disponibilité globale va croissant constamment, l'importance socio-économique de ce sujet est évidente pour les centres urbains à développement rapide de l'Asie, de l'Afrique, de l'Amérique latine et du Moyen-Orient. La infiltración de aguas residuales es a menudo un componente principal de la recarga total en acuíferos ubicados en torno a zonas urbanas, especialmente en los climas más áridos. A pesar de ello, dicho componente todavía es una consecuencia secundaria (o incluso accidental) de diversas prácticas asociadas con la manipulación de las aguas residuales y con la reutilitzación de aguas depuradas. Este tema se revisa mediante referencias a ciertas áreas en las que existen investigación detallada de campo, identificando enfoques pragmáticos con el fin de reducir el riesgo de contaminación de las aguas subterráneas por tales prácticas, a la vez tratando de conservar los beneficios para los recursos del acuífero. Dado que los efluentes de aguas residuales urbanas son probablemente la única `fuente natural' cuya disponibilidad global se halla en del aumento, la importancia socioeconómica de este tema será evidente para los centros urbanos de rápido desarrollo en Asia, Latinoamérica y Oriente Medio.

  15. Using isotopes for design and monitoring of artificial recharge systems

    USGS Publications Warehouse

    Contributors: Hendriksson, N.; Kulongoski, J.T.; Massmann, G.; Newman, B.

    2013-01-01

    Over the past years, the IAEA has provided support to a number of Member States engaged in the implementation of hydrological projects dealing with the design and monitoring of artificial recharge ( A R ) systems, primarily situated in arid and semiarid regions. AR is defined as any engineered system designed to introduce water to, and store water in, underlying aquifers. Aquifer storage and recovery (ASR) is a specific type of AR used with the purpose of increasing groundwater resources. Different water management strategies have been tested under various geographical, hydrological and climatic regimes. However, the success of such schemes cannot easily be predicted, since many variables need to be taken into account in the early stages of every AR project.

  16. DOM in recharge waters of the Santa Ana River Basin

    USGS Publications Warehouse

    Leenheer, J.A.; Aiken, G.R.; Woodside, G.; O'Connor-Patel, K.

    2007-01-01

    The urban Santa Ana River in California is the primary source of recharge water for Orange County's groundwater basin, which provides water to more than two million residents. This study was undertaken to determine the unidentified portion of dissolved organic matter (DOM) in various natural surface and reclaimed waters of the Santa Ana River Basin and to assess the potential health risk of this material. The most abundant organic contaminants were anionic detergent degradation products (constituting about 12% of the DOM), which have no known adverse health effects. In addition, high percentages of dissolved colloids from bacterial cell walls were found during storm flows; these colloids foul membranes used in water treatment. Although no significant health risks were ascribed to the newly characterized DOM, the authors note that even the small amounts of humic substances deposited during storm flow periods were responsible for significant increases in disinfection by_product formation potential in these waters.

  17. Layered cathode materials for lithium ion rechargeable batteries

    DOEpatents

    Kang, Sun-Ho; Amine, Khalil

    2007-04-17

    A number of materials with the composition Li.sub.1+xNi.sub..alpha.Mn.sub..beta.Co.sub..gamma.M'.sub..delta.O.sub.2-- zF.sub.z (M'=Mg,Zn,Al,Ga,B,Zr,Ti) for use with rechargeable batteries, wherein x is between about 0 and 0.3, .alpha. is between about 0.2 and 0.6, .beta. is between about 0.2 and 0.6, .gamma. is between about 0 and 0.3, .delta. is between about 0 and 0.15, and z is between about 0 and 0.2. Adding the above metal and fluorine dopants affects capacity, impedance, and stability of the layered oxide structure during electrochemical cycling.

  18. Using HDR (Hot Dry Rock) technology to recharge The Geysers

    SciTech Connect

    Brown, D.W.; Robinson, B.A.

    1990-01-01

    The main reason for the productivity decline at The Geysers geothermal field is obvious: more fluid is being withdrawn from the reservoir than is being returned by reinjection and natural recharge. However, there is another factor that may be contributing to this decline --- the method of reinjection. By reinjecting cold condensate directly into the steam dome as is the current practice, the very large pressure difference between the injected condensate and the underpressured reservoir guarantees that the reinjected fluid will fall rapidly to the bottom of the reservoir, with very little residence time for heat transfer. This point is very important since the vast majority of the heat contained in The Geysers geothermal field is stored in the hot rock comprising the reservoir. 10 refs., 4 figs.

  19. Identifying recharge from tropical cyclonic storms, Baja California Sur, Mexico.

    PubMed

    Eastoe, Christopher J; Hess, Greg; Mahieux, Susana

    2015-04-01

    Groundwater in the Todos Santos watershed in southern Baja California, and throughout the peninsula south of latitude 28°N, has values of (δ18 O‰, δD‰) ranging between (-8.3, -57) and (-10.9, -78). Such negative values are uncharacteristic of the site latitude near the sea level. Altitude effects do not explain the isotope data. Tropical depressions originating along the Pacific coast of North America yield rain with isotopic depletion; rain from these weather systems in southern Arizona commonly has δ18O values<-10‰ in comparison with amount-weighted mean summer and fall rain at -6‰. Isotope data indicate hurricane rain as the predominant source of recharge in southern Baja California, where named tropical depressions bring large rains (>50 mm) at least once every 2 to 3 years, and along the Pacific coast between Jalisco and Oaxaca. PMID:24635484

  20. Status of the development of rechargeable lithium cells

    NASA Technical Reports Server (NTRS)

    Halpert, G.; Surampudi, S.; Shen, D.; Huang, C-K.; Narayanan, S.; Vamos, E.; Perrone, D.

    1993-01-01

    The progress in the development of the ambient temperature lithium - titanium disulfide rechargeable cell under development at the Jet Propulsion Laboratory is described in this paper. Originally aimed at achieving a specific energy of 100 Wh/kg, 'AA' cells have demonstrated 125 Wh/kg at the C/3 discharge rate. The results of evaluating cell design parameters are discussed and cycling test data are also included in the paper. Safety tests results at various over-charge and over discharge conditions and rates proved to be uneventful. The test results of cell with built-in overcharge mechanism proved the concept was feasible. Replacing the lithium foil electrode with a Li(x)C resulted in a capacity at 1mA/cm(exp 2) of 200 mAh/gm and 235 mAh/gm at 0.167 mA.

  1. Resilient design of recharging station networks for electric transportation vehicles

    SciTech Connect

    Kris Villez; Akshya Gupta; Venkat Venkatasubramanian

    2011-08-01

    As societies shift to 'greener' means of transportation using electricity-driven vehicles one critical challenge we face is the creation of a robust and resilient infrastructure of recharging stations. A particular issue here is the optimal location of service stations. In this work, we consider the placement of battery replacing service station in a city network for which the normal traffic flow is known. For such known traffic flow, the service stations are placed such that the expected performance is maximized without changing the traffic flow. This is done for different scenarios in which roads, road junctions and service stations can fail with a given probability. To account for such failure probabilities, the previously developed facility interception model is extended. Results show that service station failures have a minimal impact on the performance following robust placement while road and road junction failures have larger impacts which are not mitigated easily by robust placement.

  2. Moisture content and recharge estimates at the Yakima Barricade borehole

    SciTech Connect

    Murphy, E.M.; Szescody, J.E.; Phillips, S.J.

    1991-12-01

    The DOE Deep Microbiology Program recently drilled a borehole near the Yakima Barricade, west of the 200 Areas. The area is vegetated by mature sagebrush. The borehole was drilled by cable tool and approximately every 1.5 m, sediment samples were collected in a bucket by the drill site geologist. Sediment samples for moisture content were sealed quickly Samples of opportunity'' were collected for the HSPA program (Hanford Site Performance Assessment), Isotope Recharge task. It should be noted that, although many QA Level II procedures were incorporated into the dulling and sampling, the Deep Microbiology Program is officially designated QA Level III, and therefore, the recharge values that we report here should only be usedfor planning purposes. A series of graphs illustrate the moisture content and chloride profiles in the Hanford Forrmtion at the Yakima Barricade Borehole. The gravimetric moisture content generally ranges between 0.01 and 0.08 in the first 70 m of sediment (only the first 30 m are shown in the figure), values that are typically found at the Hanford Site. The stratigraphy of this borehole is also attached. The first 1.5 m of the soil profile is Warden silt loam (designated eolian), followed by over 50 m of Hanford Formation. The Hanford Formation is composed of unconsolidated sands, silts, and gravels that were carried into the area by glacial flood waters during the close of the last Ice Age. Below the Hanford Formation is the Ringold Formation composed of semiconsolidated sediments. The water table is located at a depth of approximately 100 m.

  3. Moisture content and recharge estimates at the Yakima Barricade borehole

    SciTech Connect

    Murphy, E.M.; Szescody, J.E.; Phillips, S.J.

    1991-12-01

    The DOE Deep Microbiology Program recently drilled a borehole near the Yakima Barricade, west of the 200 Areas. The area is vegetated by mature sagebrush. The borehole was drilled by cable tool and approximately every 1.5 m, sediment samples were collected in a bucket by the drill site geologist. Sediment samples for moisture content were sealed quickly ``Samples of opportunity`` were collected for the HSPA program (Hanford Site Performance Assessment), Isotope Recharge task. It should be noted that, although many QA Level II procedures were incorporated into the dulling and sampling, the Deep Microbiology Program is officially designated QA Level III, and therefore, the recharge values that we report here should only be usedfor planning purposes. A series of graphs illustrate the moisture content and chloride profiles in the Hanford Forrmtion at the Yakima Barricade Borehole. The gravimetric moisture content generally ranges between 0.01 and 0.08 in the first 70 m of sediment (only the first 30 m are shown in the figure), values that are typically found at the Hanford Site. The stratigraphy of this borehole is also attached. The first 1.5 m of the soil profile is Warden silt loam (designated eolian), followed by over 50 m of Hanford Formation. The Hanford Formation is composed of unconsolidated sands, silts, and gravels that were carried into the area by glacial flood waters during the close of the last Ice Age. Below the Hanford Formation is the Ringold Formation composed of semiconsolidated sediments. The water table is located at a depth of approximately 100 m.

  4. Fiber Optic Distributed Temperature Sensing of Recharge Basin Percolation Dynamics

    NASA Astrophysics Data System (ADS)

    Becker, M.; Allen, E. M.; Hutchinson, A.

    2014-12-01

    Infiltration (spreading) basins are a central component of managed aquifer and recovery operations around the world. The concept is simple. Water is percolated into an aquifer where it can be withdrawn at a later date. However, managing infiltration basins can be complicated by entrapped air in sediments, strata of low permeability, clogging of the recharge surface, and biological growth, among other factors. Understanding the dynamics of percolation in light of these complicating factors provides a basis for making management decisions that increase recharge efficiency. As an aid to understanding percolation dynamics, fiber optic distribute temperature sensing (DTS) was used to track heat as a tracer of water movement in an infiltration basin. The diurnal variation of temperature in the basin was sensed at depth. The time lag between the oscillating temperature signal at the surface and at depth indicated the velocity of water percolation. DTS fiber optic cables were installed horizontally along the basin and vertically in boreholes to measure percolation behavior. The horizontal cable was installed in trenches at 0.3 and 1 m depth, and the vertical cable was installed using direct push technology. The vertical cable was tightly wound to produce a factor of 10 increase in spatial resolution of temperature measurements. Temperature was thus measured every meter across the basin and every 10 cm to a depth of 10 m. Data from the trenched cable suggested homogeneous percolation across the basin, but infiltration rates were a function of stage indicating non-ideal percolation. Vertical temperature monitoring showed significant lateral flow in sediments underlying the basin both during saturation and operation of the basin. Deflections in the vertical temperature profile corresponded with fine grained layers identified in core samples indicating a transient perched water table condition. The three-dimensional flow in this relatively homogenous surficial geology calls into question the relevance of simple wetting models for predicting percolation behavior in infiltration basins.

  5. Balance Problems

    MedlinePlus

    ... often, it could be a sign of a balance problem. Balance problems can make you feel unsteady or as ... fall-related injuries, such as hip fracture. Some balance problems are due to problems in the inner ...

  6. Improvement in the capacity and safety of lithium/inorganic electrolyte sulfur dioxide rechargeable cells, phase 2

    NASA Astrophysics Data System (ADS)

    Schlaikjer, Carl R.; Jones, Medlinda D.; Johnson, Arden P.; Torkelson, James E.; Vanschalkwijk, Walter

    1990-11-01

    The objective was to develop a prototype rechargeable lithium/sulfur dioxide/carbon cell, using practical AA size hardware, in which the electrolyte was to be a sulfur dioxide solution of lithium bromide or thiocyanate, together with a highly soluble cosolute, a second non-lithium salt of the same anion. The cosolute was intended to replace the organic cosolvents familiar from the primary cells, and hopefully, to improve lithium plating efficiency and electrolyte stability during cycling. The primary discharge capacities for AA size cells containing 1.25M CsBr/0.12 M LiBr/SO2 were only about 400mAh, while secondary and subsequent capacities were less than 200 mAh. The rates of solvolysis of bromide and of thiocyanate were exacerbated apparently both by the high anion concentrations and by increased lithium ion concentration. Lithium/sulfur dioxide/carbon rechargeable cells were examined in which the electrolytes were mixtures of tetrachloro aluminate salts in sulfur dioxide, to take advantage of the better performance, but to face the problem of limited capacity. It was determined that the capacity of lithium/bromine soluble positive cells was being limited by the loss of electrical contact between the carbon and the positive electrode current collector. Also, lithium plating efficiency was poor.

  7. Impacts of river recharge on groundwater level and hydrochemistry in the lower reaches of Heihe River Watershed, northwestern China

    NASA Astrophysics Data System (ADS)

    Xi, Haiyang; Feng, Qi; Si, Jianhua; Chang, Zongqiang; Cao, Shengkui

    2010-05-01

    Water resources have been overexploited for agricultural irrigation and industrial production in the upper and middle reaches of the Heihe River, northwestern China. Due to inadequate water resources management, the runoff entering into the lower reaches has been continuously reduced in recent years. The Heihe River is the primary recharge source for the groundwater of the lower reaches, so the decrease in runoff has caused the groundwater level to decline. As a result, a series of ecological and environmental problems has now appeared in the lower reaches, including river-flow interruptions, drying up of associated lakes, degeneration of vegetative cover and so on. In view of these issues, the National Water Diversion Project was put into practice in July 2000. It has significantly increased the quantity and frequency of flows entering into the lower reaches of the Heihe River, and has recharged the groundwater and improved the water quality to some degree along the length of the river. The water deliveries have had obvious influences on the groundwater in the lower reaches. The groundwater level increase and groundwater quality improvement have been of great benefit in restoring the ecological environment that was destroyed in past years.

  8. Energy-constrained open-system magmatic processes IV: Geochemical, thermal and mass consequences of energy-constrained recharge, assimilation and fractional crystallization (EC-RAFC)

    SciTech Connect

    Wendy A. Bohrson Department of Geological Sciences, Central Washington University, Ellensburg, Washington, 98926, USA; Frank J. Spera Institute for Crustal Studies and Department of Geological Sciences, University of California, Santa Barbara, California, 93106, USA

    2003-07-01

    A wealth of geochemical and petrological data provide evidence that the processes of fractional crystallization, assimilation, and magma recharge (replenishment) dominate the chemical signatures of many terrestrial igneous rocks. Previous work [ Spera and Bohrson, 2001 ; Bohrson and Spera, 2001 ] has established the importance of integrating energy, species and mass conservation into simulations of complex magma chamber processes. An extended version of the energy-constrained formulation, Energy-Constrained Recharge, Assimilation, Fractional Crystallization (EC-RAFC), tracks mass and compositional variations of melt, cumulates, and enclaves in a magma body undergoing simultaneous recharge, assimilation, and fractional crystallization [ Spera and Bohrson, 2002 ]. Because many EC-RAFC results are distinct from those predicted by extant RAFC formulations, the primary goal of this paper is to present a range of geochemical and mass relationships for selected cases that highlight issues relevant to modern petrology. Among the plethora of petrologic problems that have important, well-documented analogues in nature are the geochemical distinctions that arise when a magma body undergoes continuous versus episodic recharge, the connection between erupted magmas and associated cumulate bodies, the behavior of recharge-fractionation dominated systems (RFC), thermodynamic conditions that promote the formation of enclaves versus cumulates, and the conditions under which magma bodies may be described as chemically homogeneous. Investigation of the effects of continuous versus episodic recharge for mafic magma undergoing RAFC in the lower crust indicates that the resulting geochemical trends for melt and solids are sensitive to the intensity and composition of recharge, suggesting that EC-RAFC may be used as a tool to distinguish the nature of the recharge events. Compared to the record preserved in melts, the geochemical and mass characteristics of solids associated with particular RAFC events may record a more complete view of the physiochemical history of an open-system magma body. The capability of EC-RAFC to track melts and solids creates a genetic link that can be compared to natural analogues such as layered mafic intrusions and flood basalts, or mafic enclaves and their intermediate-composition volcanic or plutonic hosts. The ability to quantify chemical and volume characteristics of solids and melts also underscores the need for integrated field, petrologic and geochemical studies of igneous systems. While it appears that a number of volcanic events or systems may be characterized by continuous influx or eruption of magma (“steady state systems”), reports describing compositional homogeneity for products that represent eruptions of more than one event are relatively rare. In support of this, EC-RAFC results indicate that very specific combinations of recharge conditions, bulk distribution coefficients, and element concentrations are required to achieve geochemical homogeneity during cooling of a magma body undergoing RAFC. In summary, critical points are that EC-RAFC provides a method to quantitatively investigate complex magmatic systems in a thermodynamic context; it predicts complex, nonmonotonic geochemical trends for which there are natural analogues that have been difficult to model; and finally, EC-RAFC establishes the link between the chemical and physical attributes of a magmatic system. Application of EC-RAFC promises to improve our understanding of specific tectonomagmatic systems as well as enhance our grasp of the essential physiochemical principles that govern magma body evolution.

  9. Understanding and quantifying focused, indirect groundwater recharge from ephemeral streams using water table fluctuations

    NASA Astrophysics Data System (ADS)

    Cuthbert, M. O.; Acworth, R. I.; Andersen, M. S.; Larsen, J. R.; McCallum, A. M.; Rau, G. C.; Tellam, J. H.

    2016-02-01

    Understanding and managing groundwater resources in drylands is a challenging task, but one that is globally important. The dominant process for dryland groundwater recharge is thought to be as focused, indirect recharge from ephemeral stream losses. However, there is a global paucity of data for understanding and quantifying this process and transferable techniques for quantifying groundwater recharge in such contexts are lacking. Here we develop a generalized conceptual model for understanding water table and groundwater head fluctuations due to recharge from episodic events within ephemeral streams. By accounting for the recession characteristics of a groundwater hydrograph, we present a simple but powerful new water table fluctuation approach to quantify focused, indirect recharge over both long term and event time scales. The technique is demonstrated using a new, and globally unparalleled, set of groundwater observations from an ephemeral stream catchment located in NSW, Australia. We find that, following episodic streamflow events down a predominantly dry channel system, groundwater head fluctuations are controlled by pressure redistribution operating at three time scales from vertical flow (days to weeks), transverse flow perpendicular to the stream (weeks to months), and longitudinal flow parallel to the stream (years to decades). In relative terms, indirect recharge decreases almost linearly away from the mountain front, both in discrete monitored events as well as in the long-term average. In absolute terms, the estimated indirect recharge varies from 80 to 30 mm/a with the main uncertainty in these values stemming from uncertainty in the catchment-scale hydraulic properties.

  10. Using CRD method for quantification of groundwater recharge in the Gaza Strip, Palestine

    NASA Astrophysics Data System (ADS)

    Baalousha, Husam

    2005-10-01

    Rainfall is the main source of groundwater recharge in the Gaza Strip area in Palestine. The area is located in the semi-arid zone and there is no source of recharge other than rainfall. Estimation of groundwater recharge from rainfall is not an easy task since it depends on many uncertain parameters. The cumulative rainfall departure (CRD) method, which depends on the water balance principle, was used in this study to estimate the net groundwater recharge from rainfall. This method does not require much data as is the case with other classical recharge estimation methods. The CRD method was carried out using optimisation approach to minimise the root mean square error (RMSE) between the measured and the simulated groundwater head. The results of this method were compared with the results of other recharge estimation methods from literature. It was found that the results of the CRD method are very close to the results of the other methods, but with less data requirements and greater ease of application. Based on the CRD method, the annual amount of groundwater recharge from rainfall in the Gaza Strip is about 43 million m3.

  11. Artificial recharge experiments on the Ship Creek alluvial fan, Anchorage, Alaska

    USGS Publications Warehouse

    Anderson, Gary S.

    1977-01-01

    During the summers of 1973 and 174, water from Ship Creek, Alaska, was diverted at an average rate of approximately 6 cfs (cubic feet per second) to an 11-acre recharge basin. Maximum sustained unit recharge for the basin was approximately 1.4 feet per day. During 1975 a second basin of 8 acres was also used for recharge, and the total diversion rate was increased to as much as 30 cfs. The second basin was never completely filled, but the unit recharge rate was at least four times as great as that in the first basin. During 1973 and 1974, when only one recharge basin was in operation, a maximum rise of 18 feet was observed in the ground-water table near the basin. In 1975, when both basins were being used, the maximum rise was 30 feet in the same area. During 1973 and 1974, the water-level rise was 12 and 8 feet in the unconfined and confined systems, respectively, at a point 4,400 feet downgradient from the basins; in 1975 the rise at the same point was 31 and 16 feet, respectively. The potentiometric rise that was achieved in the confined aquifer during summer operation of the recharge basins was quickly dissipated when diversion stopped and the basins drained. Thus the benefits of recharge would not persist into late winter, the critical period for water availability in Anchorage, unless diversion to the basins could be continued until January or February. (Woodard-USGS)

  12. A large-scale simulation model to assess karstic groundwater recharge over Europe and the Mediterranean

    NASA Astrophysics Data System (ADS)

    Hartmann, A.; Gleeson, T.; Rosolem, R.; Pianosi, F.; Wada, Y.; Wagener, T.

    2015-06-01

    Karst develops through the dissolution of carbonate rock and is a major source of groundwater contributing up to half of the total drinking water supply in some European countries. Previous approaches to model future water availability in Europe are either too-small scale or do not incorporate karst processes, i.e. preferential flow paths. This study presents the first simulations of groundwater recharge in all karst regions in Europe with a parsimonious karst hydrology model. A novel parameter confinement strategy combines a priori information with recharge-related observations (actual evapotranspiration and soil moisture) at locations across Europe while explicitly identifying uncertainty in the model parameters. Europe's karst regions are divided into four typical karst landscapes (humid, mountain, Mediterranean and desert) by cluster analysis and recharge is simulated from 2002 to 2012 for each karst landscape. Mean annual recharge ranges from negligible in deserts to > 1 m a-1 in humid regions. The majority of recharge rates range from 20 to 50% of precipitation and are sensitive to subannual climate variability. Simulation results are consistent with independent observations of mean annual recharge and significantly better than other global hydrology models that do not consider karst processes (PCR-GLOBWB, WaterGAP). Global hydrology models systematically under-estimate karst recharge implying that they over-estimate actual evapotranspiration and surface runoff. Karst water budgets and thus information to support management decisions regarding drinking water supply and flood risk are significantly improved by our model.

  13. Comparison of recharge estimates at a small watershed in east-central Pennsylvania, USA

    USGS Publications Warehouse

    Risser, D.W.; Gburek, W.J.; Folmar, G.J.

    2009-01-01

    The common recommendation that recharge should be estimated from multiple methods is sound, but the inherent differences of the methods make it difficult to assess the accuracy of differing results. In this study, four methods for estimating groundwater recharge and two methods for estimating base flow (as a proxy for recharge) are compared at two hydrologic research sites in east-central Pennsylvania, USA. Results from the multiple methods all provided reasonable estimates of groundwater recharge that differed considerably. The estimates of mean annual recharge for the period 1994-2001 ranged from 22.9 to 35.7 cm - about 45% of the mean of all estimates. For individual years, recharge estimates from the multiple methods ranged from 30 to 42% of the mean value during the dry years and 64 to 76% of the mean value during wet years. Comparison of multiple methods was found to be useful for determining the range of plausible recharge rates and highlighting the uncertainty of the estimates. ?? US Government 2008.

  14. Estimating groundwater recharge beneath irrigated farmland using environmental tracers fluoride, chloride and sulfate

    NASA Astrophysics Data System (ADS)

    Lin, Dan; Jin, Menggui; Liang, Xing; Zhan, Hongbin

    2013-11-01

    Accurate recharge estimation is essential for effective groundwater management, especially in the North China Plain, where irrigation return flow is significant to vertical recharge but brings difficulty for recharge estimation. Three environmental tracers (F-, Cl- and SO4 2-) were used to estimate vertical recharge based on the mass balance and cumulative methods. Four boreholes were dry-drilled to 5-25 m depth beneath irrigated farmland and one was drilled to 5 m beneath non-irrigated woodland; soil samples were collected in all boreholes at set depths. The results indicated that F-, Cl- and SO4 2-were suitable tracers beneath the non-irrigated woodland, yielding recharge rates of 16.9, 18.8 and 19.4 mm/year, respectively. Recharge estimation was not straightforward when taking account of crop type, irrigation and/or fertilizer use. After comparing with previous research, conclusions were drawn: Cl- was an appropriate tracer for irrigated farmland when taking account of Cl- input from irrigation and absorption by crops; recharge rates were 65.9-126.8 mm/year. However, F- was a more suitable tracer for irrigated regions where account is made of the proportion of precipitation to irrigation return flow, provided low F- concentrations can be measured reliably.

  15. Interactions of diffuse and focused allogenic recharge in an eogenetic karst aquifer (Florida, USA)

    NASA Astrophysics Data System (ADS)

    Langston, Abigail L.; Screaton, Elizabeth J.; Martin, Jonathan B.; Bailly-Comte, Vincent

    2012-06-01

    The karstic upper Floridan aquifer in north-central Florida (USA) is recharged by both diffuse and allogenic recharge. To understand how recharged water moves within the aquifer, water levels and specific conductivities were monitored and slug tests were conducted in wells installed in the aquifer surrounding the Santa Fe River Sink and Rise. Results indicate that diffuse recharge does not mix rapidly within the aquifer but instead flows horizontally. Stratification may be aided by the high matrix porosity of the eogenetic karst aquifer. Purging wells for sample collection perturbed conductivity for several days, reflecting mixing of the stratified water and rendering collection of representative samples difficult. Interpretive numerical simulations suggest that diffuse recharge impacts the intrusion of allogenic water from the conduit by increasing hydraulic head in the surrounding aquifer and thereby reducing influx to the aquifer from the conduit. In turn, the increase of head within the conduits affects flow paths of diffuse recharge by moving newly recharged water vertically as the water table rises and falls. This movement may result in a broad vertical zone of dissolution at the water table above the conduit system, with thinner and more focused water-table dissolution at greater distance from the conduit.

  16. Identification of processes affecting excess air formation during natural bank filtration and managed aquifer recharge

    NASA Astrophysics Data System (ADS)

    Massmann, Gudrun; Sültenfuß, Jürgen

    2008-09-01

    SummaryManaged aquifer recharge is gaining importance as a practice to bank and treat surface water for drinking water production. Neon (Ne) concentrations were analysed at four different recharge sites in and near Berlin, where groundwater is recharged directly from surface water courses, either by near-natural bank filtration, induced bank filtration or engineered basin recharge. Neon concentrations in excess of saturation (ΔNe) were used to identify excess air in the infiltrates. Excess air concentrations were around saturation at the near-natural bank filtration site, where river water infiltrates through a permeable river bed into a confined aquifer under completely saturated conditions. At two induced unconfined bank filtration sites, samples generally contained excess air (up to 60% ΔNe). Highest excess air concentrations (up to 81% ΔNe) were encountered at the engineered basin recharge site. The degree of water table fluctuations, the water saturation of the sediments in the infiltration zone and the presence of a confining layer affect the formation of excess air. Excess air can only be used to trace bank filtrate or artificially recharged water in a setting where the ambient groundwater in the near vicinity of production wells is not affected by large water-table fluctuations. Nevertheless, excess air concentrations provide valuable additional information on the type of recharge (saturated or unsaturated, degree of water table fluctuations).

  17. Responses of groundwater recharge to land-cover changes and climate variability

    NASA Astrophysics Data System (ADS)

    Guan, Huade; Xu, Xiang; Ding, Zhenyu; Deng, Zijuan; Simmons, Craig; Hutson, John; Love, Andy; Ajami, Hoori

    2014-05-01

    It is estimated that groundwater directly provides drinking water for 1.5 billion people in the world. Anthropogenic activities during the past 200 years have led to the conversion of large areas of natural forest and grassland to cropland and pasture. Understanding and quantification of changes in groundwater recharge after surface vegetation alteration are important not only for water resource management, but also for land-use and land-cover management. On the other hand, groundwater recharge also responds to climate variability and changes. In this paper, we discuss two groundwater recharge estimation methods of different temporal resolution: chloride mass balance (CMB), and storage-discharge relationship (S-Q). Application of the CMB method over areas of historical forest clearance, or recent plantation, suffers from two difficulties: pre-clearance (or pre-plantation) recharge may have been contaminated by recharge that occurred after forest clearance (or plantation); and the post-clearance (or post-plantation) recharge may not yet have reached new chloride equilibrium. In coastal areas, strong spatial variability in chloride deposition leads to an additional difficulty in appropriately applying the CMB method. This presentation will discuss some recent development to address these difficulties. Meanwhile, an improved conceptual framework of the S-Q method for estimating seasonal and inter-annual variability of groundwater recharge is presented as well. Both are shown with case studies based at the Mount Lofty Ranges of South Australia.

  18. A simulation model to assess groundwater recharge over Europe's karst regions

    NASA Astrophysics Data System (ADS)

    Hartmann, A.; Gleeson, T.; Rosolem, R.; Pianosi, F.; Wada, Y.; Wagener, T.

    2014-11-01

    Karst develops through the dissolution of carbonate rock and is a major source of groundwater contributing up to half of the total drinking water supply in some European countries. Previous approaches to model future water availability in Europe are either too-small scale or do not incorporate karst processes, i.e. preferential flow paths. This study presents the first simulations of groundwater recharge in all karst regions in Europe with a parsimonious karst hydrology model. A novel parameter confinement strategy combines a priori information with recharge-related observations (actual evapotranspiration and soil moisture) at locations across Europe while explicitly identifying uncertainty in the model parameters. Europe's karst regions are divided into 4 typical karst landscapes (humid, mountain, Mediterranean and desert) by cluster analysis and recharge is simulated from 2002 to 2012 for each karst landscape. Mean annual recharge ranges from negligible in deserts to > 1 m a-1 in humid regions. The majority of recharge rates ranges from 20-50% of precipitation and are sensitive to sub-annual climate variability. Simulation results are consistent with independent observations of mean annual recharge and significantly better than other global hydrology models that do not consider karst processes (PCR-GLOBWB, WaterGAP). Global hydrology models systematically underestimate karst recharge implying that they over-estimate actual evapotranspiration and surface runoff. Karst water budgets and thus information to support management decisions regarding drinking water supply and flood risk are significantly improved by our model.

  19. Fuel cell technology for lunar surface operations

    NASA Astrophysics Data System (ADS)

    Deronck, Henry J.

    1992-02-01

    Hydrogen-oxygen fuel cells have been shown, in several NASA and contractor studies, to be an enabling technology for providing electrical power for lunar bases, outposts, and vehicles. The fuel cell, in conjunction with similar electrolysis cells, comprises a closed regenerative energy storage system, commonly referred to as a regenerative fuel cell (RFC). For stationary applications, energy densities of 1,000 watt-hours per kilograms an order of magnitude over the best rechargeable batteries, have been projected. In this RFC, the coupled fuel cell and electrolyzer act as an ultra-light battery. Electrical energy from solar arrays 'charges' the system by electrolyzing water into hydrogen and oxygen. When an electrical load is applied, the fuel cell reacts the hydrogen and oxygen to 'discharge' usable power. Several concepts for utilizing RFC's, with varying degrees of integration, have been proposed, including both primary and backup roles. For mobile power needs, such as rovers, an effective configuration may be to have only the fuel cell located on the vehicle, and to use a central electrolysis 'gas station'. Two fuel cell technologies are prime candidates for lunar power system concepts: alkaline electrolyte and proton exchange membrane. Alkaline fuel cells have been developed to a mature production power unit in NASA's Space Shuttle Orbiter. Recent advances in materials offer to significantly improve durability to the level needed for extended lunar operations. Proton exchange membrane fuel cells are receiving considerable support for hydrospace and terrestrial transportation applications. This technology promises durability, simplicity, and flexibility.

  20. An Overview of Stationary Fuel Cell Technology

    SciTech Connect

    DR Brown; R Jones

    1999-03-23

    Technology developments occurring in the past few years have resulted in the initial commercialization of phosphoric acid (PA) fuel cells. Ongoing research and development (R and D) promises further improvement in PA fuel cell technology, as well as the development of proton exchange membrane (PEM), molten carbonate (MC), and solid oxide (SO) fuel cell technologies. In the long run, this collection of fuel cell options will be able to serve a wide range of electric power and cogeneration applications. A fuel cell converts the chemical energy of a fuel into electrical energy without the use of a thermal cycle or rotating equipment. In contrast, most electrical generating devices (e.g., steam and gas turbine cycles, reciprocating engines) first convert chemical energy into thermal energy and then mechanical energy before finally generating electricity. Like a battery, a fuel cell is an electrochemical device, but there are important differences. Batteries store chemical energy and convert it into electrical energy on demand, until the chemical energy has been depleted. Depleted secondary batteries may be recharged by applying an external power source, while depleted primary batteries must be replaced. Fuel cells, on the other hand, will operate continuously, as long as they are externally supplied with a fuel and an oxidant.

  1. Fuel cell technology for lunar surface operations

    NASA Technical Reports Server (NTRS)

    Deronck, Henry J.

    1992-01-01

    Hydrogen-oxygen fuel cells have been shown, in several NASA and contractor studies, to be an enabling technology for providing electrical power for lunar bases, outposts, and vehicles. The fuel cell, in conjunction with similar electrolysis cells, comprises a closed regenerative energy storage system, commonly referred to as a regenerative fuel cell (RFC). For stationary applications, energy densities of 1,000 watt-hours per kilograms an order of magnitude over the best rechargeable batteries, have been projected. In this RFC, the coupled fuel cell and electrolyzer act as an ultra-light battery. Electrical energy from solar arrays 'charges' the system by electrolyzing water into hydrogen and oxygen. When an electrical load is applied, the fuel cell reacts the hydrogen and oxygen to 'discharge' usable power. Several concepts for utilizing RFC's, with varying degrees of integration, have been proposed, including both primary and backup roles. For mobile power needs, such as rovers, an effective configuration may be to have only the fuel cell located on the vehicle, and to use a central electrolysis 'gas station'. Two fuel cell technologies are prime candidates for lunar power system concepts: alkaline electrolyte and proton exchange membrane. Alkaline fuel cells have been developed to a mature production power unit in NASA's Space Shuttle Orbiter. Recent advances in materials offer to significantly improve durability to the level needed for extended lunar operations. Proton exchange membrane fuel cells are receiving considerable support for hydrospace and terrestrial transportation applications. This technology promises durability, simplicity, and flexibility.

  2. Iron-Air Rechargeable Battery: A Robust and Inexpensive Iron-Air Rechargeable Battery for Grid-Scale Energy Storage

    SciTech Connect

    2010-10-01

    GRIDS Project: USC is developing an iron-air rechargeable battery for large-scale energy storage that could help integrate renewable energy sources into the electric grid. Iron-air batteries have the potential to store large amounts of energy at low cost—iron is inexpensive and abundant, while oxygen is freely obtained from the air we breathe. However, current iron-air battery technologies have suffered from low efficiency and short life spans. USC is working to dramatically increase the efficiency of the battery by placing chemical additives on the battery’s iron-based electrode and restructuring the catalysts at the molecular level on the battery’s air-based electrode. This can help the battery resist degradation and increase life span. The goal of the project is to develop a prototype iron-air battery at significantly cost lower than today’s best commercial batteries.

  3. Comparison of different estimation techniques to quantify groundwater recharge in Pirna, Germany

    NASA Astrophysics Data System (ADS)

    Ringleb, Jana; Sallwey, Jana; Stefan, Catalin

    2015-04-01

    Water scarcity in combination with groundwater exploitation is a major concern worldwide because of climate change, population growth and rising water demand. To be able to sustainably manage and protect groundwater resources, it is necessary to quantify the amount of water which leaks through the unsaturated zone and recharges the aquifer naturally. However, quantifying the spatial and temporal distribution of recharge is difficult because of soil heterogeneity and the influence of vegetation. For that reason and because field measurements of recharge are difficult to obtain, models are valuable tools to quantify recharge. Numerical models need a lot of parameters which are hard to measure and hence can only be estimated. Therefore analytical models or empirical equations which use less and / or easier obtainable parameters could estimate groundwater recharge as well as numerical models because of the underlying uncertainty in parameter estimation. Recharge estimation methods which use different model approaches and have varying complexity were compared at Pirna test field site, Germany to select suitable methods which will later be integrated into a web-based Decision Support System (DSS) developed for the sustainable management of groundwater. The complexity of the used methods covers numerical models, analytical models as well as empirical equations. Different model approaches were used to estimate groundwater recharge including amongst others a groundwater flow model, an unsaturated zone model and a watershed model. The resulting groundwater recharge estimates received from the numerical and analytical models and from empirical equations were compared to evaluate whether the methods are suitable to estimate groundwater recharge considering the complexity, data requirements and time-consumption of each method.

  4. Artificial groundwater recharge zones mapping using remote sensing and GIS: a case study in Indian Punjab.

    PubMed

    Singh, Amanpreet; Panda, S N; Kumar, K S; Sharma, Chandra Shekhar

    2013-07-01

    Artificial groundwater recharge plays a vital role in sustainable management of groundwater resources. The present study was carried out to identify the artificial groundwater recharge zones in Bist Doab basin of Indian Punjab using remote sensing and geographical information system (GIS) for augmenting groundwater resources. The study area has been facing severe water scarcity due to intensive agriculture for the past few years. The thematic layers considered in the present study are: geomorphology (2004), geology (2004), land use/land cover (2008), drainage density, slope, soil texture (2000), aquifer transmissivity, and specific yield. Different themes and related features were assigned proper weights based on their relative contribution to groundwater recharge. Normalized weights were computed using the Saaty's analytic hierarchy process. Thematic layers were integrated in ArcGIS for delineation of artificial groundwater recharge zones. The recharge map thus obtained was divided into four zones (poor, moderate, good, and very good) based on their influence to groundwater recharge. Results indicate that 15, 18, 37, and 30 % of the study area falls under "poor," "moderate," "good," and "very good" groundwater recharge zones, respectively. The highest recharge potential area is located towards western and parts of middle region because of high infiltration rates caused due to the distribution of flood plains, alluvial plain, and agricultural land. The least effective recharge potential is in the eastern and middle parts of the study area due to low infiltration rate. The results of the study can be used to formulate an efficient groundwater management plan for sustainable utilization of limited groundwater resources. PMID:23775493

  5. Silt and gas accumulation beneath an artificial recharge spreading basin, Southwestern Utah, U.S.A.

    USGS Publications Warehouse

    Heilweil, V.M.; Solomon, D.K.; Ortiz, G.

    2009-01-01

    Sand Hollow Reservoir in southwestern Utah, USA, is operated for both surface-water storage and artificial recharge to the underlying Navajo Sandstone. The total volume of estimated artificial recharge between 2002 and 2007 is 85 million cubic meters (69,000 acre-feet). Since 2002, artificial recharge rates have generally been declining and are inversely correlated with the increasing surface area of the reservoir. Permeability testing of core samples retrieved from beneath the reservoir indicates that this decline may not be due to silt accumulation. Artificial recharge rates also show much seasonal variability. Calculations of apparent intrinsic permeability show that these variations can only partly be explained by variation in water viscosity associated with seasonal changes in water temperature. Sporadic seasonal trends in recharge rates and intrinsic permeability during 2002-2004 could be associated with the large fluctuations in reservoir elevation and wetted area. From 2005 through 2007, the reservoir was mostly full and there has been a more consistent seasonal pattern of minimum recharge rates during the summer and maximum rates during the autumn. Total dissolved-gas pressure measurements indicate the presence of biogenic gas bubbles in the shallow sediments beneath the shallower parts of Sand Hollow Reservoir when the water is warmer. Permeability reduction associated with this gas clogging may contribute to the decrease in artificial recharge rates during the spring and summer, with a subsequently increasing recharge rates in the autumn associated with a decline in volume of gas bubbles. Other possible causes for seasonal variation in artificial recharge rates require further investigation.

  6. Multi-scale experimental programs for estimating groundwater recharge in hydrologically changing basins

    NASA Astrophysics Data System (ADS)

    McIntyre, Neil; Larsen, Josh; Reading, Lucy; Bulovic, Nevenka; Jarihani, Abdollah; Finch, Warren

    2015-04-01

    Groundwater recharge estimates are required to evaluate sustainable groundwater abstractions and to support groundwater impacts assessments associated with minerals and energy extraction. Increasingly, recharge estimates are also needed for regional and global scale water cycle modelling. This is especially the case in the great arid and semi-arid basins of the world due to increased water scarcity and dependence of ecosystems and livelihoods on their water supplies, and the considerable potential influence of groundwater on the hydrological cycle. Groundwater resources in the semi-arid Surat Basin of south-east Queensland, Australia, support extensive groundwater-dependent ecosystems and have historically been utilised for regional agriculture and urban water-use. Large volumes of water are currently being produced and will continue to do so as a part of coal seam gas extraction. There is considerable uncertainty about the impacts of gas extraction on water resources and the hydrological cycle, and much of this uncertainty stems from our limited knowledge about recharge processes and how to upscale them. Particular questions are about the role of storm events in controlling annual recharge, the relative contributions of local 'recharge zones' versus diffuse recharge and the translation of (relatively easily quantified) shallow drainage estimates to groundwater recharge. A multi-scale recharge research program is addressing these questions, using multiple approaches in estimating groundwater recharge, including plot and catchment scale monitoring, use of remote sensed data and simulation models. Results during the first year of the program have resulted in development of process hypotheses and experimental designs at three field sites representing key gaps in knowledge. The presentation will overview the process of designing the experimental program; how the results from these sites will be integrated with existing knowledge; and how results will be used to advance our knowledge of the changing hydrological cycle in the Surat Basin.

  7. Estimation of shallow ground-water recharge in the Great Lakes basin

    USGS Publications Warehouse

    Neff, B.P.; Piggott, A.R.; Sheets, R.A.

    2006-01-01

    This report presents the results of the first known integrated study of long-term average ground-water recharge to shallow aquifers (generally less than 100 feet deep) in the United States and Canada for the Great Lakes, upper St. Lawrence, and Ottawa River Basins. The approach used was consistent throughout the study area and allows direct comparison of recharge rates in disparate parts of the study area. Estimates of recharge are based on base-flow estimates for streams throughout the Great Lakes Basin and the assumption that base flow in a given stream is equal to the amount of shallow ground-water recharge to the surrounding watershed, minus losses to evapotranspiration. Base-flow estimates were developed throughout the study area using a single model based on an empirical relation between measured base-flow characteristics at streamflow-gaging stations and the surficial-geologic materials, which consist of bedrock, coarse-textured deposits, fine-textured deposits, till, and organic matter, in the surrounding surface-water watershed. Model calibration was performed using base-flow index (BFI) estimates for 959 stations in the U.S. and Canada using a combined 28,784 years of daily streamflow record determined using the hydrograph-separation software program PART. Results are presented for watersheds represented by 8-digit hydrologic unit code (HUC, U.S.) and tertiary (Canada) watersheds. Recharge values were lowest (1.6-4.0 inches/year) in the eastern Lower Peninsula of Michigan; southwest of Green Bay, Wisconsin; in northwestern Ohio; and immediately south of the St. Lawrence River northeast of Lake Ontario. Recharge values were highest (12-16.8 inches/year) in snow shadow areas east and southeast of each Great Lake. Further studies of deep aquifer recharge and the temporal variability of recharge would be needed to gain a more complete understanding of ground-water recharge in the Great Lakes Basin.

  8. Artificial Groundwater Recharge Zones Mapping Using Remote Sensing and GIS: A Case Study in Indian Punjab

    NASA Astrophysics Data System (ADS)

    Singh, Amanpreet; Panda, S. N.; Kumar, K. S.; Sharma, Chandra Shekhar

    2013-07-01

    Artificial groundwater recharge plays a vital role in sustainable management of groundwater resources. The present study was carried out to identify the artificial groundwater recharge zones in Bist Doab basin of Indian Punjab using remote sensing and geographical information system (GIS) for augmenting groundwater resources. The study area has been facing severe water scarcity due to intensive agriculture for the past few years. The thematic layers considered in the present study are: geomorphology (2004), geology (2004), land use/land cover (2008), drainage density, slope, soil texture (2000), aquifer transmissivity, and specific yield. Different themes and related features were assigned proper weights based on their relative contribution to groundwater recharge. Normalized weights were computed using the Saaty's analytic hierarchy process. Thematic layers were integrated in ArcGIS for delineation of artificial groundwater recharge zones. The recharge map thus obtained was divided into four zones (poor, moderate, good, and very good) based on their influence to groundwater recharge. Results indicate that 15, 18, 37, and 30 % of the study area falls under "poor," "moderate," "good," and "very good" groundwater recharge zones, respectively. The highest recharge potential area is located towards western and parts of middle region because of high infiltration rates caused due to the distribution of flood plains, alluvial plain, and agricultural land. The least effective recharge potential is in the eastern and middle parts of the study area due to low infiltration rate. The results of the study can be used to formulate an efficient groundwater management plan for sustainable utilization of limited groundwater resources.

  9. Comparative study of climate-change scenarios on groundwater recharge, southwestern Mississippi and southeastern Louisiana, USA

    NASA Astrophysics Data System (ADS)

    Beigi, Ehsan; Tsai, Frank T.-C.

    2015-02-01

    A geographic information system (GIS)-based water-budget framework has been developed to study the climate-change impact on regional groundwater recharge, and it was applied to the Southern Hills aquifer system of southwestern Mississippi and southeastern Louisiana, USA. The framework links historical climate variables and future emission scenarios of climate models to a hydrologic model, HELP3, to quantify spatiotemporal potential recharge variations from 1950 to 2099. The framework includes parallel programming to divide a large amount of HELP3 simulations among multiple cores of a supercomputer, to expedite computation. The results show that a wide range of projected potential recharge for the Southern Hills aquifer system resulted from the divergent projections of precipitation, temperature and solar radiation using three scenarios (B1, A2 and A1FI) of the National Center for Atmospheric Research's Parallel Climate Model 1 (PCM) and the National Oceanic and Atmospheric Administration Geophysical Fluid Dynamics Lab's (GFDL) model. The PCM model projects recharge change ranging from -33.7 to +19.1 % for the 21st century. The GFDL model projects less recharge than the PCM, with recharge change ranging from -58.1 to +7.1 %. Potential recharge is likely to increase in 2010-2039, but likely to decrease in 2070-2099. Projected recharge is more sensitive to the changes in the projected precipitation than the projected solar radiation and temperature. Uncertainty analysis confirms that the uncertainty in projected precipitation yields more changes in the potential recharge than in the projected temperature for the study area.

  10. Partitioning sources of recharge in environments with groundwater recirculation using carbon-14 and CFC-12

    NASA Astrophysics Data System (ADS)

    Bourke, Sarah A.; Cook, Peter G.; Dogramaci, Shawan; Kipfer, Rolf

    2015-06-01

    Groundwater recirculation occurs when groundwater is pumped from an aquifer onto the land surface, and a portion of that water subsequently infiltrates back to the aquifer. In environments where groundwater is recirculated, differentiation between various sources of recharge (e.g. natural rainfall recharge vs. recirculated water) can be difficult. Groundwater age indicators, in particular transient trace gases, are likely to be more sensitive tracers of recharge than stable isotopes or chloride in this setting. This is because, unlike stable isotopes or chloride, they undergo a process of equilibration with the atmosphere, and historical atmospheric concentrations are known. In this paper, groundwater age indicators (14C and CFC-12) were used as tracers of recharge by surplus mine water that is discharged to streams. Ternary mixing ratios were calculated based on 14C and CFC-12 concentrations measured along three transects of piezometers and monitoring wells perpendicular to the creeks, and from dewatering wells. Uncertainty in calculated mixing ratios was estimated using a Monte Carlo approach. Ternary mixing ratios in dewatering wells suggest that recharge by mine water accounted for between 10% and 87% of water currently abstracted by dewatering wells. The calculated mixing ratios suggest that recharge by mine water extends to a distance of more than 550 m from the creeks. These results are supported by seepage flux estimates based on the water and chloride balance along the creeks, which suggest that 85-90% of mine water discharged to the creeks recharges the aquifer and recharge by mine water extends between 110 and 730 m from the creeks. Mixing calculations based on gaseous groundwater age indicators could also be used to partition recharge associated with agricultural irrigation or artificial wetland supplementation.

  11. Ground-Water Recharge in the Arid and Semiarid Southwestern United States - Climatic and Geologic Framework

    USGS Publications Warehouse

    Stonestrom, David A.; Harrill, James R.

    2007-01-01

    Ground-water recharge in the arid and semiarid southwestern United States results from the complex interplay of climate, geology, and vegetation across widely ranging spatial and temporal scales. Present-day recharge tends to be narrowly focused in time and space. Widespread water-table declines accompanied agricultural development during the twentieth century, demonstrating that sustainable ground-water supplies are not guaranteed when part of the extracted resource represents paleorecharge. Climatic controls on ground-water recharge range from seasonal cycles of summer monsoonal and winter frontal storms to multimillennial cycles of glacial and interglacial periods. Precipitation patterns reflect global-scale interactions among the oceans, atmosphere, and continents. Large-scale climatic influences associated with El Ni?o and Pacific Decadal Oscillations strongly but irregularly control weather in the study area, so that year-to-year variations in precipitation and ground-water recharge are large and difficult to predict. Proxy data indicate geologically recent periods of multidecadal droughts unlike any in the modern instrumental record. Anthropogenically induced climate change likely will reduce ground-water recharge through diminished snowpack at higher elevations, and perhaps through increased drought. Future changes in El Ni?o and monsoonal patterns, both crucial to precipitation in the study area, are highly uncertain in current models. Land-use modifications influence ground-water recharge directly through vegetation, irrigation, and impermeable area, and indirectly through climate change. High ranges bounding the study area?the San Bernadino Mountains and Sierra Nevada to the west, and the Wasatch and southern Colorado Rocky Mountains to the east?provide external geologic controls on ground-water recharge. Internal geologic controls stem from tectonic processes that led to numerous, variably connected alluvial-filled basins, exposure of extensive Paleozoic aquifers in mountainous recharge areas, and distinct modes of recharge in the Colorado Plateau and Basin and Range subregions.

  12. [Population problem, comprehension problem].

    PubMed

    Tallon, F

    1993-08-01

    Overpopulation of developing countries in general, and Rwanda in particular, is not just their problem but a problem for developed countries as well. Rapid population growth is a key factor in the increase of poverty in sub-Saharan Africa. Population growth outstrips food production. Africa receives more and more foreign food, economic, and family planning aid each year. The Government of Rwanda encourages reduced population growth. Some people criticize it, but this criticism results in mortality and suffering. One must combat this ignorance, but attitudes change slowly. Some of these same people find the government's acceptance of family planning an invasion of their privacy. Others complain that rich countries do not have campaigns to reduce births, so why should Rwanda do so? The rate of schooling does not increase in Africa, even though the number of children in school increases, because of rapid population growth. Education is key to improvements in Africa's socioeconomic growth. Thus, Africa, is underpopulated in terms of potentiality but overpopulated in terms of reality, current conditions, and possibilities of overexploitation. Africa needs to invest in human resources. Families need to save, and to so, they must refrain from having many children. Africa should resist the temptation to waste, as rich countries do, and denounce it. Africa needs to become more independent of these countries, but structural adjustment plans, growing debt, and rapid population growth limit national independence. Food aid is a means for developed countries to dominate developing countries. Modernization through foreign aid has had some positive effects on developing countries (e.g., improved hygiene, mortality reduction), but these also sparked rapid population growth. Rwandan society is no longer traditional, but it is also not yet modern. A change in mentality to fewer births, better quality of life for living infants, better education, and less burden for women must occur rapidly because the problems are urgent. PMID:12287360

  13. Fuel properties of eleven vegetable oils

    SciTech Connect

    Goering, C.E.; Daugherty, M.J.; Heakin, A.J.; Pryde, E.H.; Schwab, A.W.

    1982-11-01

    Eleven vegetable oils that can be grown as domestic field crops were identified for inclusion in a comparative study of chemical and fuel properties. Sample lots of each oil were subjected to ASTM tests appropriate for diesel fuels. The tests identified some problem areas with vegetable oil fuels. The oil samples were also characterized chemically and certain fuel properties were correlated to chemical compositions.

  14. Fuel Performance Annual Report for 1980

    SciTech Connect

    Bailey, W. J.; Rising, K. H.; Tokar, M.

    1981-12-01

    This annual report, the third in a series, provides a brief description of fuel performance in conmercial nuclear power plants. Brief summaries of fuel surveillance programs and operating experience, fuel performance problems, and fuel design changes are provided. References to additional, more detailed, information and related NRC evaluation are included.

  15. Fuel Performance Annual Report for 1979

    SciTech Connect

    Tokar, M.; Mailey, W. J.; Cunningham, M. E.

    1981-01-01

    This annual report, the second in a series, provides a brief description of fuel performance in commercial nuclear power plants. Brief summaries are given of fuel surveillance programs, fuel performance problems, and fuel design changes. References to additional, more detailed, information and related NRC evaluation are provided.

  16. Groundwater recharge by channel infiltration in El Barbon basin, Baja California, Mexico

    NASA Astrophysics Data System (ADS)

    Ponce, V. M.; Pandey, R. P.; Kumar, S.

    1999-01-01

    The amount of groundwater recharge by channel infiltration is estimated for El Barbon basin, in Baja California, Mexico. The basin's lower portion includes the valleys of Ojos Negros and Real del Castillo Viejo, which are crossed by several ephemeral washes, including the mainstem El Barbon Wash. A distributed catchment model with the capability for nonlinear channel routing and channel abstraction is used to calculate groundwater recharge by channel infiltration for storm events of 2-, 5-, 10-, 25-, 50-, and 100-yr return period. The results confirm that event channel infiltration can be a substantial component of the vertical recharge.

  17. Battery charging control methods, electric vehicle charging methods, battery charging apparatuses and rechargeable battery systems

    DOEpatents

    Tuffner, Francis K.; Kintner-Meyer, Michael C. W.; Hammerstrom, Donald J.; Pratt, Richard M.

    2012-05-22

    Battery charging control methods, electric vehicle charging methods, battery charging apparatuses and rechargeable battery systems. According to one aspect, a battery charging control method includes accessing information regarding a presence of at least one of a surplus and a deficiency of electrical energy upon an electrical power distribution system at a plurality of different moments in time, and using the information, controlling an adjustment of an amount of the electrical energy provided from the electrical power distribution system to a rechargeable battery to charge the rechargeable battery.

  18. Difficulties in determining factors that influence effective groundwater recharge in Ohio

    USGS Publications Warehouse

    Ashooh, J.; Liu, J.; Mueller, E.; Sherer, S.; Woggon, N.; Dumouchelle, D.H.; Eberle, M.

    2003-01-01

    As part of a COSI Academy research project, data from a recent statewide analysis of effective groundwater recharge were reexamined by students to further discern relations between recharge and selected environmental characteristics of individual drainage basins: 1) location of the main stem of a river relative to coarse and fine surficial sediments and 2) influence of land use. Lack of sufficiently detailed data was the principal difficulty in most phases of the examination. Other than a potential relation between recharge and the percentages of agricultural and forested land, no relations were found in visual comparisons of mapped and tabulated data.

  19. Evaluation of recharge to the Skunk Creek Aquifer from a constructed wetland near Lyons, South Dakota

    USGS Publications Warehouse

    Thompson, Ryan F.

    2002-01-01

    A wetland was constructed in the Skunk Creek flood plain near Lyons in southeast South Dakota to mitigate for wetland areas that were filled during construction of a municipal golf course for the city of Sioux Falls. A water-rights permit was obtained to allow the city to pump water from Skunk Creek into the wetland during times when the wetland would be dry. The amount of water seeping through the wetland and recharging the underlying Skunk Creek aquifer was not known. The U.S. Geological Survey, in cooperation with the city of Sioux Falls, conducted a study during 1997-2000 to evaluate recharge to the Skunk Creek aquifer from the constructed wetland. Three methods were used to estimate recharge from the wetland to the aquifer: (1) analysis of the rate of water-level decline during periods of no inflow; (2) flow-net analysis; and (3) analysis of the hydrologic budget. The hydrologic budget also was used to evaluate the efficiency of recharge from the wetland to the aquifer. Recharge rates estimated by analysis of shut-off events ranged from 0.21 to 0.82 foot per day, but these estimates may be influenced by possible errors in volume calculations. Recharge rates determined by flow-net analysis were calculated using selected values of hydraulic conductivity and ranged from 566,000 gallons per day using a hydraulic conductivity of 0.5 foot per day to 1,684,000 gallons per day using a hydraulic conductivity of 1.0 foot per day. Recharge rates from the hydrologic budget varied from 0.74 to 0.85 foot per day, and averaged 0.79 foot per day. The amount of water lost to evapotranspiration at the study wetland is very small compared to the amount of water seeping from the wetland into the aquifer. Based on the hydrologic budget, the average recharge efficiency was estimated as 97.9 percent, which indicates that recharging the Skunk Creek aquifer by pumping water into the study wetland is highly efficient. Because the Skunk Creek aquifer is composed of sand and gravel, the 'recharge mound' is less distinct than might be found in an aquifer composed of finer materials. However, water levels recorded from piezometers in and around the wetland do show a higher water table than periods when the wetland was dry. The largest increases in water level occur between the wetland channel and Skunk Creek. The results of this study demonstrate that artificially recharged wetlands can be useful in recharging underlying aquifers and increasing water levels in these aquifers.

  20. Analytical Analyses of Spatial and Temporal Characteristics of Infiltrated Water for Managed Aquifer Recharge

    NASA Astrophysics Data System (ADS)

    Zlotnik, V. A.; Ledder, G.; Kacimov, A. R.

    2014-12-01

    Disposal of excessive runoff or treated sewage into wadis and ephemeral streams is a common practice and an important hydrological problem in many Middle Eastern countries. While chemical and biological properties of the injected treated wastewater may be different from those of the receiving aquifer, the density contrast between the two fluids can be small. Therefore, studies of the fluid interface for variable density fluids or water intrusion are not directly relevant in many Managed Aquifer Recharge (MAR) problems. Other factors, such as the transient nature of injection and lack of detailed aquifer information must be considered. The disposed water reaching the water table through the vadose zone creates groundwater mounds, deforms the original water table, and develops finite-size convex-concave lenses of treated water over receiving water. After cessation of infiltration, these mounds flatten, water levels become horizontal, and infiltrated water becomes fully embedded in the receiving aquifer. The shape of the treated water body is controlled by the aquifer parameters, the magnitude of ambient flow, and the duration, rate, and cyclicity of infiltration. In case of limited aquifer data, advective transport modeling offers the most appropriate tools for predicting plume shapes over time, but surprisingly little work has been done on this important 3D flow problem. We investigate the lateral and vertical spreading of infiltrated water combining techniques of spatial velocity analyses by Zlotnik and Ledder (1992, 1993) with particle tracking. This approach allows for evaluating the geometry of the plume and the protection zone, the flow development phases, and other temporal and spatial effects and results can be used in conditions of limited data availability and quality. (Funding was provided by the USAID, DAI Subcontract 1001624-12S-19745)

  1. Effects of urban storm-runoff control on ground-water recharge in Nassau County, New York

    USGS Publications Warehouse

    Ku, Henry; Hagelin, Nathan; Buxton, Herbert

    1992-01-01

    Before urban development, most ground-water recharge on Long Island, New York, occurred during the dormant season, when evapotranspiration is low. The use of recharge basins for collection and disposal of urban storm runoff in Nassau County has enabled ground-water recharge to occur also during the growing season. In contrast, the use of storm sewers to route storm runoff to streams and coastal waters has resulted in a decrease in ground-water recharge during the dormant season. The net result of these two forms of urban storm-runoff control has been an increase in annual recharge of about 12 percent in areas served by recharge basins and a decrease of about 10 percent in areas where storm runoff is routed to streams and tidewater. On a countywide basis, annual ground-water recharge has remained nearly the same as under predevelopment conditions, but its distribution pattern has changed. Redistribution resulted in increased recharge in the eastern and central parts of the county, and decreased recharge in the western and nearshore areas. Model simulation of recharge indicates that the water-table altitude has increased by as much as 5 ft above predevelopment levels in areas served by recharge basins and declined by as much as 3 feet in areas where stormwater is discharged to streams and tidewater.

  2. Comparison of spatially and temporally distributed recharge simulated using coupled and decoupled watershed hydrology models

    NASA Astrophysics Data System (ADS)

    Hevesi, J. A.; Woolfenden, L. R.; Niswonger, R. G.; Nishikawa, T.

    2011-12-01

    Estimation of the temporal and spatial distribution of watershed-scale recharge is often required for the development of transient groundwater-flow models and for quantifying water budgets. The temporal distribution of recharge has often been empirically estimated by scaling precipitation distributions. For larger watersheds, however, temporal change in the spatial distribution of recharge is affected by spatial and temporal variability in precipitation and air temperature, combined with the effects of heterogeneity in the physical characteristics of the watershed; these factors make it difficult to represent transient recharge using empirical scaling methods. Precipitation-runoff models, calibrated to available streamflow records, have been used to simulate the changing distribution and magnitude of recharge, but the uncertainty in simulated recharge estimates usually is high due to the uncertainty in input data and other components of the water balance. In this study, GSFLOW, an integrated hydrologic model, was used to evaluate differences in simulated water balances and the magnitude and distribution of transient recharge using decoupled and coupled simulations of surface-water and groundwater flow in the Santa Rosa Plain watershed (SRPW), California, USA. GSFLOW is an integration of the precipitation-runoff model PRMS and the groundwater flow model MODFLOW. GSFLOW was run as a decoupled (PRMS-only) precipitation-runoff model, independent of the MODFLOW, to develop a preliminary ensemble of estimated water balances and recharge simulations. The ensemble consisted of a set of 60-year (water years 1950 through 2010) daily simulation results, all of which provided satisfactory calibration results to available daily streamflow records at 12 gaging sites within the SRPW. The PRMs parameter files developed for the calibrated PRMS-only simulations were used as input for the coupled GSFLOW simulations that were calibrated to available well hydrographs for water years 1976 through 2008. The PRMS-only simulated water budgets and transient recharge results were compared to those produced by GSFLOW for water years 1976 through 2008. The comparison indicated that recharge estimated by GSFLOW was in many cases significantly different than recharge estimated by the PRMS-only model. Differences in recharge were pronounced along numerous stream channels in the SRPW due to the ability to directly simulate surface water - groundwater interaction in GSFLOW. In most cases, locations simulated as dominantly groundwater discharge zones (such as gaining reaches) using GSFLOW had decreased recharge relative to the decoupled PRMS-only simulations, whereas losing reaches had increased recharge compared to the PRMS-only simulations. Although the coupled GSFLOW model provided more conceptually correct recharge and water balance results, application of the decoupled model to develop preliminary recharge and water budget results allowed for a more efficient calibration of the coupled model because of the much faster runtime of PRMS-only simulations and the ease of developing preliminary water budget and recharge estimates.

  3. Indigo carmine: An organic crystal as a positive-electrode material for rechargeable sodium batteries

    NASA Astrophysics Data System (ADS)

    Yao, Masaru; Kuratani, Kentaro; Kojima, Toshikatsu; Takeichi, Nobuhiko; Senoh, Hiroshi; Kiyobayashi, Tetsu

    2014-01-01

    Using sodium, instead of lithium, in rechargeable batteries is a way to circumvent the lithium's resource problem. The challenge is to find an electrode material that can reversibly undergo redox reactions in a sodium-electrolyte at the desired electrochemical potential. We proved that indigo carmine (IC, 5,5'-indigodisulfonic acid sodium salt) can work as a positive-electrode material in not only a lithium-, but also a sodium-electrolyte. The discharge capacity of the IC-electrode was ~100 mAh g-1 with a good cycle stability in either the Na or Li electrolyte, in which the average voltage was 1.8 V vs. Na+/Na and 2.2 V vs. Li+/Li, respectively. Two Na ions per IC are stored in the electrode during the discharge, testifying to the two-electron redox reaction. An X-ray diffraction analysis revealed a layer structure for the IC powder and the DFT calculation suggested the formation of a band-like structure in the crystal.

  4. Ecological Engineering Approaches to Improve Hydraulic Properties of Infiltration Basins Designed for Groundwater Recharge.

    PubMed

    Gette-Bouvarot, Morgane; Volatier, Laurence; Lassabatere, Laurent; Lemoine, Damien; Simon, Laurent; Delolme, Cécile; Mermillod-Blondin, Florian

    2015-08-18

    Infiltration systems are increasingly used in urban areas for groundwater recharge. The reduction of sediment permeability by physical and/or biological processes is a major problem in management of infiltration systems often requiring expensive engineering operations for hydraulic performance maintenance. To reduce these costs and for the sake of sustainable development, we proposed to evaluate the ability of ecological engineering approaches to reduce the biological clogging of infiltration basins. A 36-day field-scale experiment using enclosures was performed to test the influences of abiotic (light reduction by shading) and biotic (introduction of the macrophyte Vallisneria spiralis (L.) or the gastropod Viviparus viviparus (Linnaeus, 1758)) treatments to limit benthic biofilm biomass and to maintain or even increase hydraulic performances. We coupled biological characterization of sediment (algal biomass, bacterial abundance, total organic carbon, total nitrogen, microbial enzymatic activity, photosynthetic activity, and photosystem II efficiency) with hydraulic conductivity measurements to assess the effects of treatments on sediment permeability. The grazer Viviparus viviparus significantly reduced benthic biofilm biomass and enhanced hydraulic conductivity. The other treatments did not produce significant changes in hydraulic conductivity although Vallisneria spiralis affected photosynthetic activity of biofilm. Finally, our results obtained with Viviparus viviparus are promising for the development of ecological engineering solutions to prevent biological fouling in infiltration systems. PMID:26214709

  5. Highly Conductive Solvent-Free Polymer Electrolytes for Lithium Rechargeable Batteries

    SciTech Connect

    Robert Filler, Zhong Shi and Braja Mandal

    2004-10-21

    In order to obviate the deficiencies of currently used electrolytes in lithium rechargeable batteries, there is a compelling need for the development of solvent-free, highly conducting solid polymer electrolytes (SPEs). The problem will be addressed by synthesizing a new class of block copolymers and plasticizers, which will be used in the formulation of highly conducting electrolytes for lithium-ion batteries. The main objective of this Phase-I effort is to determine the efficacy and commercial prospects of new specifically designed SPEs for use in electric and hybrid electric vehicle (EV/HEV) batteries. This goal will be achieved by preparing the SPEs on a small scale with thorough analyses of their physical, chemical, thermal, mechanical and electrochemical properties. SPEs will play a key role in the formulation of next generation lithium-ion batteries and will have a major impact on the future development of EVs/HEVs and a broad range of consumer products, e.g., computers, camcorders, cell phones, cameras, and power tools.

  6. A hybrid sequential deposition fabrication technique for micro fuel cells

    NASA Astrophysics Data System (ADS)

    Stanley, Kevin G.; Czyzewska, Eva K.; Vanderhoek, Tom P. K.; Fan, Lilian L. Y.; Abel, Keith A.; Wu, Q. M. Jonathan; Parameswaran, M. Ash

    2005-10-01

    Micro fuel cell systems have elicited significant interest due to their promise for instantly rechargeable, longer duration and portable power. Most micro fuel cell systems are either built as miniaturized plate-and-frame or silicon-based microelectromechanical systems (MEMS). Plate-and-frame systems are difficult to fabricate smaller than 20 cm3. Existing micro fuel cell designs cannot meet the cost, scale and power requirements of some portable power markets. Traditional MEMS scaling advantages do not apply to fuel cells because the minimum area for the fuel cell is fixed by the catalyst area required for a given power output, and minimum volume set by mass transport limitations. We have developed a new hybrid technique that borrows from both micro and macro machining techniques to create fuel cells in the 1-20 cm3 range, suitable for cell phones, PDAs and smaller devices.

  7. The TMI Regenerative Solid Oxide Fuel Cell

    NASA Technical Reports Server (NTRS)

    Cable, Thomas L.; Ruhl, Robert C.; Petrik, Michael

    1996-01-01

    Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. Systems generally consist of photovoltaic solar arrays which operate (during sunlight cycles) to provide system power and regenerate fuel (hydrogen) via water electrolysis and (during dark cycles) fuel cells convert hydrogen into electricity. Common configurations use two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Reliability, power to weight and power to volume ratios could be greatly improved if both power production (fuel cells) and power storage (electrolysis) functions can be integrated into a single unit. The solid oxide fuel cell (SOFC) based design integrates fuel cell and electrolyzer functions and potentially simplifies system requirements. The integrated fuel cell/electrolyzer design also utilizes innovative gas storage concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H20 electrode (SOFC anode/electrolyzer cathode) materials for regenerative fuel cells. Tests have shown improved cell performance in both fuel and electrolysis modes in reversible fuel cell tests. Regenerative fuel cell efficiencies, ratio of power out (fuel cell mode) to power in (electrolyzer mode), improved from 50 percent using conventional electrode materials to over 80 percent. The new materials will allow a single SOFC system to operate as both the electolyzer and fuel cell. Preliminary system designs have also been developed to show the technical feasibility of using the design for space applications requiring high energy storage efficiencies and high specific energy. Small space systems also have potential for dual-use, terrestrial applications.

  8. Fuel pin

    DOEpatents

    Christiansen, D.W.; Karnesky, R.A.; Leggett, R.D.; Baker, R.B.

    1987-11-24

    A fuel pin for a liquid metal nuclear reactor is provided. The fuel pin includes a generally cylindrical cladding member with metallic fuel material disposed therein. At least a portion of the fuel material extends radially outwardly to the inner diameter of the cladding member to promote efficient transfer of heat to the reactor coolant system. The fuel material defines at least one void space therein to facilitate swelling of the fuel material during fission.

  9. Ground-water pumpage and artificial recharge estimates for calendar year 2000 and average annual natural recharge and interbasin flow by hydrographic area, Nevada

    USGS Publications Warehouse

    Lopes, Thomas J.; Evetts, David M.

    2004-01-01

    Nevada's reliance on ground-water resources has increased because of increased development and surface-water resources being fully appropriated. The need to accurately quantify Nevada's water resources and water use is more critical than ever to meet future demands. Estimated ground-water pumpage, artificial and natural recharge, and interbasin flow can be used to help evaluate stresses on aquifer systems. In this report, estimates of ground-water pumpage and artificial recharge during calendar year 2000 were made using data from a variety of sources, such as reported estimates and estimates made using Landsat satellite imagery. Average annual natural recharge and interbasin flow were compiled from published reports. An estimated 1,427,100 acre-feet of ground water was pumped in Nevada during calendar year 2000. This total was calculated by summing six categories of ground-water pumpage, based on water use. Total artificial recharge during 2000 was about 145,970 acre-feet. At least one estimate of natural recharge was available for 209 of the 232 hydrographic areas (HAs). Natural recharge for the 209 HAs ranges from 1,793,420 to 2,583,150 acre-feet. Estimates of interbasin flow were available for 151 HAs. The categories and their percentage of the total ground-water pumpage are irrigation and stock watering (47 percent), mining (26 percent), water systems (14 percent), geothermal production (8 percent), self-supplied domestic (4 percent), and miscellaneous (less than 1 percent). Pumpage in the top 10 HAs accounted for about 49 percent of the total ground-water pumpage. The most ground-water pumpage in an HA was due to mining in Pumpernickel Valley (HA 65), Boulder Flat (HA 61), and Lower Reese River Valley (HA 59). Pumpage by water systems in Las Vegas Valley (HA 212) and Truckee Meadows (HA 87) were the fourth and fifth highest pumpage in 2000, respectively. Irrigation and stock watering pumpage accounted for most ground-water withdrawals in the HAs with the sixth through ninth highest pumpage. Geothermal production accounted for most pumpage in the Carson Desert (HA 101). Reinjection of ground water pumped for geothermal energy production accounted for about 64 percent (93,310 acre-feet) of the total artificial recharge. The only artificial recharge by water systems was in Las Vegas Va