Note: This page contains sample records for the topic fuel recharge problem from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: November 12, 2013.
1

Recharge  

SciTech Connect

This chapter describes briefly the nature and measurement of recharge in support of the CH2M HILL Tank Farm Vadose Zone Project. Appendix C (Recharge) and the Recharge Data Package (Fayer and Keller 2007) provide a more thorough and extensive review of the recharge process and the estimation of recharge rates for the forthcoming RCRA Facility Investigation report for Hanford single-shell tank (SST) Waste Management Areas (WMAs).

Fayer, Michael J.

2008-01-17

2

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

National Technical Information Service (NTIS)

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 emiss...

F. Mitlitsky N. J. Colella B. Myers

1994-01-01

3

Comparison of Areal-Recharge and Regional-Flux Driven Henry Problems  

NASA Astrophysics Data System (ADS)

The intrusion of saltwater into a groundwater aquifer is one of the most important water resource issues in coastal areas. A small fraction of the intruded salt can increase salinity levels in the extracted drinking water from an impacted aquifer. Therefore, the location of the interface between the freshwater and saltwater, commonly known as the saltwater wedge, should be carefully predicted in coastal areas to avoid an unexpected contamination of the drinking water. Numerical models provide more realistic predictions near the coastal area if it considers the effects of the density contrast between salt and fresh waters. These models are often validated by solving standard problems, such as the Henry problem, which is the most common benchmark used for testing density-coupled models. The Henry problem only considers groundwater introduced into the system from a regional flux boundary. In this study, we consider local recharge boundary condition to introduce groundwater flow into the system. We use the finite difference model SEAWAT to obtain the solution on this recharge-driven Henry problem and compare the results against the traditional Henry problem. Furthermore, laboratory experiments were completed to verify the validity of the numerical simulation results. Both transient and steady-state results for the recharge-driven Henry problem will be compared against flux driven Henry problem data, previously obtained in our laboratory (Simpson and Clement, 2004; Goswami and Clement, 2007; Abarca and Clement, 2009).

Chang, S.; Clement, P.

2009-12-01

4

Unitized Regenerative Fuel Cells for solar rechargeable aircraft and zero emission vehicles  

Microsoft Academic Search

A unitized regenerative fuel cell (URFC) produces power and electrolytically regenerates its reactants using a single stack of reversible cells. URFC'S have been designed for high altitude long endurance (HALE) solar rechargeable aircraft (SRA), zero emission vehicles (ZEV's), hybrid energy storage\\/propulsion systems for long duration satellites, energy storage for remote (off-grid) power sources, and peak shaving for on-grid applications. URFC's

Fred Mitlitsky; Nicholas J. Colella; Blake Myers

1994-01-01

5

Using MODFLOW 2000 to model ET and recharge for shallow ground water problems.  

PubMed

In environments with shallow ground water elevation, small changes in the water table can cause significant variations in recharge and evapotranspiration fluxes. Particularly, where ground water is close to the soil surface, both recharge and evapotranspiration are regulated by a thin unsaturated zone and, for accuracy, must be represented using nonconstant and often nonlinear relationships. The most commonly used ground water flow model today, MODFLOW, was originally designed with a modular structure with independent packages representing recharge and evaporation processes. Systems with shallow ground water, however, may be better represented using either a recharge function that varies with ground water depth or a continuous recharge and evapotranspiration function that is dependent on depth to water table. In situations where the boundaries between recharging and nonrecharging cells change with time, such as near a seepage zone, a continuous ground water flux relationship allows recharge rates to change with depth rather than having to calculate them at each stress period. This research article describes the modification of the MODFLOW 2000 recharge and segmented evapotranspiration packages into a continuous recharge-discharge function that allows ground water flux to be represented as a continuous process, dependent on head. The modifications were then used to model long-term recharge and evapotranspiration processes on a saline, semiarid floodplain in order to understand spatial patterns of salinization, and an overview of this process is given. PMID:18624693

Doble, Rebecca C; Simmons, Craig T; Walker, Glen R

2008-06-28

6

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

SciTech Connect

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.

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

1994-09-06

7

Unitized Regenerative Fuel Cells for solar rechargeable aircraft and zero emission vehicles  

NASA Astrophysics Data System (ADS)

A unitized regenerative fuel cell (URFC) produces power and electrolytically regenerates its reactants using a single stack of reversible cells. URFC'S have been designed for high altitude long endurance (HALE) solar rechargeable aircraft (SRA), zero emission vehicles (ZEV's), hybrid energy storage/propulsion systems for long duration satellites, energy storage for remote (off-grid) power sources, and peak shaving for on-grid applications. URFC's 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 ZEV's using hydrogen/air with oxygen supercharging. Overlapping and synergistic development and testing opportunities for these two technologies will be highlighted.

Mitlitsky, Fred; Colella, Nicholas J.; Myers, Blake

1994-09-01

8

Water Table Fluctuations Induced by Intermittent Recharge  

Microsoft Academic Search

The problem of water table fluctuations in response to repeated recharges is considered. The effect on the water table of intermittent constant recharge (recharge applied intermittently at a constant rate) and of intermittent instantaneous recharge (recharge applied instantaneoulsy at regular intervals) is analyzed in detail. The final results are shown to consist of a combination of periodic and transient components;

Marinus Maasland

1959-01-01

9

Radiation Effects Problems in Nuclear Fuel Rods  

Microsoft Academic Search

This paper will review some of the radiation effects problems that have been encountered in nuclear fuel rods. Examples are drawn from both the commercial Light Water Reactors (LWR) and the new, developing Liquid Metal Fast Breeder Reactors (LMFBR). The performance of a particular fuel rod is influenced by (1) the interaction between the ceramic fuel pellet column and the

J. T. A. Roberts

1975-01-01

10

Safeguards for spent fuels: Verification problems  

SciTech Connect

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.

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

1991-01-01

11

THE FISSION GAS PROBLEM FOR MOBILE FUEL FAST REACTORS  

Microsoft Academic Search

The problems that might result from the release of fission gases in ; mobile fuel fast reactors are considered for two types of mobile fuel systems; ; namely, a molten alloy fuel system of the type to be used in the Los Alamos ; Molten Plutonium Reactor Experiment and a paste fuel system of the type being ; developad by

F. G. Hammitt; E. C. Kovacic; F. J. Leitz

1960-01-01

12

Rechargeable Alkaline Zinc System.  

National Technical Information Service (NTIS)

Rechargeable alkaline zinc batteries have been investigated heretofore as power sources capable of high energy density applications. One of the major problems with their use is the short circuiting of the unit cells by growth of zinc dendrites from the an...

O. C. Wagner

1970-01-01

13

Advanced Rechargeable Batteries, Phase 2.  

National Technical Information Service (NTIS)

In the framework of the program Advanced rechargeable batteries, intended to evaluate the suitability, the applicability and possible problems of advanced batteries on naval ships (both surface and submarine) studies and tests have been performed on two p...

I. D. Schmal I. W. ter Veen I. C. Kluiters

1999-01-01

14

Study on Clogging Mechanism and Control Methods of Artificial Recharge  

Microsoft Academic Search

The severe global fresh water shortage, the over-exploitation of groundwater and its related ecological environment geology problems, the global climate change, all of them are stimulating the study and practice of artificial recharge. But the clogging problem during artificial recharge is always to be the most common obstacle, it can reduce the recharge rate, increase the maintenance cost and shorten

Xueyan Ye; Xinqiang Du; Shengtao Li; Yuesuo Yang

2010-01-01

15

Mechanical modeling of porous oxide fuel pellet A Test Problem  

SciTech Connect

A poro-elasto-plastic material model has been developed to capture the response of oxide fuels inside the nuclear reactors under operating conditions. Behavior of the oxide fuel and variation in void volume fraction under mechanical loading as predicted by the developed model has been reported in this article. The significant effect of void volume fraction on the overall stress distribution of the fuel pellet has also been described. An important oxide fuel issue that can have significant impact on the fuel performance is the mechanical response of oxide fuel pellet and clad system. Specifically, modeling the thermo-mechanical response of the fuel pellet in terms of its thermal expansion, mechanical deformation, swelling due to void formation and evolution, and the eventual contact of the fuel with the clad is of significant interest in understanding the fuel-clad mechanical interaction (FCMI). These phenomena are nonlinear and coupled since reduction in the fuel-clad gap affects thermal conductivity of the gap, which in turn affects temperature distribution within the fuel and the material properties of the fuel. Consequently, in order to accurately capture fuel-clad gap closure, we need to account for fuel swelling due to generation, retention, and evolution of fission gas in addition to the usual thermal expansion and mechanical deformation. Both fuel chemistry and microstructure also have a significant effect on the nucleation and growth of fission gas bubbles. Fuel-clad gap closure leading to eventual contact of the fuel with the clad introduces significant stresses in the clad, which makes thermo-mechanical response of the clad even more relevant. The overall aim of this test problem is to incorporate the above features in order to accurately capture fuel-clad mechanical interaction. Because of the complex nature of the problem, a series of test problems with increasing multi-physics coupling features, modeling accuracy, and complexity are defined with the objective of accurate simulation of fuel-clad mechanical interaction subjected to a wide-range of thermomechanical stimuli.

Nukala, Phani K [ORNL; Barai, Pallab [ORNL; Simunovic, Srdjan [ORNL; Ott, Larry J [ORNL

2009-10-01

16

Zero-CO2 emission and low-crossover 'rechargeable' PEM fuel cells using cyclohexane as an organic hydrogen reservoir.  

PubMed

High performance (open circuit voltage = 920 mV, maximum power density = 14-15 mW cm(-2)) of the PEM fuel cell was achieved by using cyclohexane as a fuel with zero-CO2 emission and lower-crossover through PEM than with a methanol-based fuel cell. PMID:12703775

Kariya, Nobuko; Fukuoka, Atsushi; Ichikawa, Masaru

2003-03-21

17

Portable photovoltaic battery recharger  

Microsoft Academic Search

A portable photovoltaic battery recharger is described for simultaneously recharging a plurality of rechargeable batteries having different sizes and respective optimum charging current levels, comprising: a plurality of photovoltaic solar cell arrays corresponding to the number of different battery sizes, each of the cell arrays having a plurality of individual solar cells, each cell of a respective array having a

A. M. Ricaud; F. Artigliere

1989-01-01

18

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

USGS Publications Warehouse

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

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

1989-01-01

19

Rechargeable zinc halogen battery  

SciTech Connect

A rechargeable zinc halogen battery has an aqueous electrolyte containing ions of zinc and halogen and an amount of polysaccharide and/or sorbitol sufficient to prevent zinc dendrite formation during recharging. The electrolyte may also contain trace amounts of metals such as tungsten, molybdenum, and lead. 7 tables.

Spaziante, P.M.; Nidola, A.

1980-01-01

20

Portable photovoltaic battery recharger  

SciTech Connect

A portable photovoltaic battery recharger is described for simultaneously recharging a plurality of rechargeable batteries having different sizes and respective optimum charging current levels, comprising: a plurality of photovoltaic solar cell arrays corresponding to the number of different battery sizes, each of the cell arrays having a plurality of individual solar cells, each cell of a respective array having a selectively chosen surface area for generating the respective optimum charging current levels when insolated; battery receptacle means for holding the plurality of rechargeable batteries in a recharging position; and circuit means for connecting the plurality of photovoltaic solar cell arrays to the battery receptacle means to charge each of the different size batteries with the respective optimum charging current level.

Ricaud, A.M.; Artigliere, F.

1989-02-28

21

Recharging robot teams: A tanker approach  

Microsoft Academic Search

We examine the use of a tanker robot to distribute energy in a system of autonomous robots. Consider a team of autonomous mobile worker robots performing some task, each with a finite but rechargeable energy supply such as a battery or fuel cell. To work, the robots must expend energy. To expend more energy than is contained in a single

Pawel Zebrowski; Richard T. Vaughan

2005-01-01

22

Benchmark Problem Suite for Reactor Physics Study of LWR Next Generation Fuels  

Microsoft Academic Search

This paper proposes a benchmark problem suite for studying the physics of next-generation fuels of light water reactors. The target discharge burnup of the next-generation fuel was set to 70 GWd\\/t considering the increasing trend in discharge burnup of light water reactor fuels. The UO2 and MOX fuels are included in the benchmark specifications. The benchmark problem consists of three

Akio YAMAMOTO; Tadashi IKEHARA; Takuya ITO; Etsuro SAJI

2002-01-01

23

Identifying and quantifying urban recharge: a review  

NASA Astrophysics Data System (ADS)

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. Résumé. Les origines et les trajets de la recharge des nappes en zones urbaines sont plus nombreux et plus complexes qu'en zones rurales. Les bâtiments, les routes et les autres infrastructures de surface se combinent avec les réseaux de drainage artificiels en modifiant les voies d'écoulements des précipitations. Une partie de la recharge directe est perdue, mais une recharge supplémentaire peut intervenir à partir des systèmes de drainage d'eaux pluviales. Des quantités importantes d'eau sont importées dans la plupart des villes pour l'alimentation, sont distribuées par des conduites souterraines et sont collectées dans des égouts ou des fosses septiques. Les fuites de ces réseaux de conduites constituent souvent une part importante de la recharge. L'origine de la recharge en zones urbaines est mise en évidence grâce à la piézométrie, aux signatures chimiques et aux bilans hydrologiques. Ces trois approches posent des problèmes. La recharge est quantifiée soit à partir de ses composantes individuelles (la recharge directe, les fuites d'eaux des réseaux, les fosses septiques, etc.), soit de façon globale. Pour travailler avec les composantes individuelles, il faut de grandes quantités de données, dont beaucoup comportent des incertitudes, et le résultat final présentera vraisemblablement des incertitudes importantes. Les approches globales recommandées s'appuient sur la modélisation de l'aquifère et les bilans de solutés, dans lesquels différents types de données sont intégrés. La recharge en zone urbaine reste un sujet délaissé par la recherche, offrant dans la littérature peu d'études de cas de bonne qualité. Resumen. Las fuentes y vías de recarga en zonas urbanas son más numerosas y complejas que en medios rurales. Los edificios, carreteras y otras infraestructuras superficiales se combinan con las obras antrópicas de drenaje para modificar las vías de infiltración. Una parte de la recarga directa se pierde, pero puede haber contribuciones adicionales a partir de los sistemas de drenaje de aguas pluviales. Se importa grandes volúmenes de agua a la mayoría de las ciudades para abastecimiento, siendo distribuida por medio de tuberías subterráneas, y recogida de nuevo en alcantarillas o fosas sépticas. Las pérdidas en las redes de distribución a menudo aportan una recarga substancial. Las fuentes de recarga en zonas urbanas se identifican mediante la piezometría, trazadores químicos y balances de agua, pero los tres métodos presentan problemas. La recarga se cuantifica bien por sus componentes individuales (recarga directa, goteo en tuberías, fosas sépticas, etc.) o bien de forma holística. La primera opción requiere muchos datos, a menudo inciertos, y es probable que se obtengan enormes incertidumbres en el resultado fin

Lerner, David

2002-01-01

24

Direct Methanol Fuel Cells: Fundamentals, Problems and Perspectives  

Microsoft Academic Search

\\u000a Fuel cells are chemoelectric engines that convert the chemical energy of a fuel directly into electricity. The process is\\u000a an electrochemical reaction akin to a battery, but unlike the battery, fuel cells do not store the chemicals internally and\\u000a instead use a continuous supply of fuel from an external storage tank. Accordingly, fuel cell systems have the potential to\\u000a solve

Keith Scott; Ashok K. Shuklab

25

Artificial Groundwater Recharge, San Luis Valley, Colorado.  

National Technical Information Service (NTIS)

Intense use of aquifers for irrigation waters has caused groundwater storage depletion in many areas of the arid and semi-arid west, including the San Luis Valley in south central Colorado. Artificial recharge is a means of alleviating this problem. To sh...

D. K. Sunada J. W. Warner D. J. Molden

1983-01-01

26

An approach to identify urban groundwater recharge  

Microsoft Academic Search

Evaluating the proportion in which waters from different origins are mixed in a given water sample is relevant for many hydrogeological problems, such as quantifying total recharge, assessing groundwater pollution risks, or managing water resources. Our work is motivated by urban hydrogeology, where waters with different chemical signature can be identified (losses from water supply and sewage networks, infiltration from

E. Vázquez-Suñé; J. Carrera; I. Tubau; X. Sánchez-Vila; A. Soler

2010-01-01

27

Universal connector for rechargeable and non-rechargeable batteries  

Microsoft Academic Search

In an electrical product having battery recharging means and a load adapted for energization from a battery, a battery connector is described which consists of: terminal means adapted to contact the output terminals of either a non-rechargeable battery having a first physical configuration or a rechargeable battery having a second physical configuration, the terminal means coupled to the load of

G. R. Mundschenk; R. C. Decker

1986-01-01

28

Fuel Cell Application Problems: Study Guide for AP Chemistry  

NSDL National Science Digital Library

This study guide is intended for 10th-12th grade AP chemistry students studying fuel cell technology. Applicable National Science Education Standards are included in the document. The study guide includes a comparison of gasoline and hydrogen, a section on kinetic molecular theory, a section on electrochemistry and material on hydrogen fuel cells. This document may be downloaded in PDF file format.

Cox, Brian A.

2012-07-31

29

Apparatus for charging rechargeable battery  

Microsoft Academic Search

A rechargeable battery is supplied with a charging voltage from a charging voltage source and exhibits a charging voltage characteristic having a peak shortly before the rechargeable battery reaches a fully charged state. A resistor voltage dividing circuit having a plurality of voltage output terminals is connected to both terminals of the rechargeable battery. A voltage memory device is provided

K. Oyamada; K. Tada

1982-01-01

30

Rechargeable galvanic cell  

Microsoft Academic Search

An improved rechargeable cell is described which has an anode structure which in its uncharged state comprises a coherent metallic porous body with its pores substantially filled with oxidized zinc and alkaline electrolyte. This anode structure is generated in situ, within the cell, by exposing a predetermined admixture of active zinc metal and an oxide of a metal less anodically

1978-01-01

31

Electrical isolation problems in underground fuel storage tanks and piping.  

National Technical Information Service (NTIS)

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...

E. M. Vessel C. F. Jenkins

1994-01-01

32

U.S. Policy Response to the Fuels Management Problem: An ...  

Treesearch

... written or produced by Forest Service personnel and are in the public domain. ... Management Problem: An Analysis of the Public Debate About the Healthy Forests ... Fuels Management-How to Measure Success: Conference Proceedings.

33

REMOTELY RECHARGEABLE EPD  

SciTech Connect

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.

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

2007-11-13

34

The timing of EV recharging and its effect on utilities  

SciTech Connect

Electric vehicles (EV's) represent an important future load on the electric utility system which, if properly managed, could increase power plant utilization and reduce the average cost of generating electricity. A future EV population of 7.5 million is addressed, together with its characteristics, vehicle use, consequent recharging loads, and the impact of EV's on electric utilities in terms of the generation of electric power, fuel use, and costs. The impact on utilities will depend in part on when the vehicles are recharged. If the price of electricity is uniform throughout the day, recharging is likely to begin when vehicles are parked at home. Most of the recharging would then occur during late afternoon and early evening hours when other demands for electricity are high. In the year 2000, peak electricity demand would increase by 5700 MW, and oil- and gas-fired power plants would generate 39 percent of the recharge power. Marginal generating costs would average 7.6 cents/kWh in 1982 dollars. If electricity were priced by time of day, recharging could shift to late night hours when the other demands for electricity are low. The peak demand would increase by only 400 MW; 27 percent of the power would come from oil and gas, and marginal generating costs would average only 5.1 cents/kWh, some 25 percent less than the marginal cost of the system load without EV's. The fuels to recharge EV's were found to vary from one region of the country to the next. Utilities in the northeast would use the most oil and gas for recharging (more than 75 percent), while those in the central part of the country would use the least.

Collins, M.M.; Mader, G.H.

1983-02-01

35

Electrical isolation problems in underground fuel storage tanks and piping  

Microsoft Academic Search

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

E. M. Vessel; C. F. Jenkins

1994-01-01

36

An approach to identify urban groundwater recharge  

NASA Astrophysics Data System (ADS)

Evaluating the proportion in which waters from different origins are mixed in a given water sample is relevant for many hydrogeological problems, such as quantifying total recharge, assessing groundwater pollution risks, or managing water resources. Our work is motivated by urban hydrogeology, where waters with different chemical signature can be identified (losses from water supply and sewage networks, infiltration from surface runoff and other water bodies, lateral aquifers inflows, ...). The relative contribution of different sources to total recharge can be quantified by means of solute mass balances, but application is hindered by the large number of potential origins. Hence, the need to incorporate data from a large number of conservative species, the uncertainty in sources concentrations and measurement errors. We present a methodology to compute mixing ratios and end-members composition, which consists of (i) Identification of potential recharge sources, (ii) Selection of tracers, (iii) Characterization of the hydrochemical composition of potential recharge sources and mixed water samples, and (iv) Computation of mixing ratios and reevaluation of end-members. The analysis performed in a data set from samples of the Barcelona city aquifers suggests that the main contributors to total recharge are the water supply network losses (22%), the sewage network losses (30%), rainfall, concentrated in the non-urbanized areas (17%), from runoff infiltration (20%), and the Besòs River (11%). Regarding species, halogens (chloride, fluoride and bromide), sulfate, total nitrogen, and stable isotopes (18O, 2H, and 34S) behaved quite conservatively. Boron, residual alkalinity, EDTA and Zn did not. Yet, including these species in the computations did not affect significantly the proportion estimations.

Vázquez-Suñé, E.; Carrera, J.; Tubau, I.; Sánchez-Vila, X.; Soler, A.

2010-10-01

37

An approach to identify urban groundwater recharge  

NASA Astrophysics Data System (ADS)

Evaluating the proportion in which waters from different origins are mixed in a given water sample is relevant for many hydrogeological problems, such as quantifying total recharge, assessing groundwater pollution risks, or managing water resources. Our work is motivated by urban hydrogeology, where waters with different chemical signature can be identified (losses from water supply and sewage networks, infiltration from surface runoff and other water bodies, lateral aquifers inflows, ...). The relative contribution of different sources to total recharge can be quantified by means of solute mass balances, but application is hindered by the large number of potential origins. Hence, the need to incorporate data from a large number of conservative species, the uncertainty in sources concentrations and measurement errors. We present a methodology to compute mixing ratios and end-members composition, which consists of (i) Identification of potential recharge sources, (ii) Selection of tracers, (iii) Characterization of the hydrochemical composition of potential recharge sources and mixed water samples, and (iv) Computation of mixing ratios and reevaluation of end-members. The analysis performed in a data set from samples of the Barcelona city aquifers suggests that the main contributors to total recharge are the water supply network losses (22%), the sewage network losses (30%), rainfall, concentrated in the non-urbanized areas (17%), from runoff infiltration (20%), and the Besòs River (11%). Regarding species, halogens (chloride, fluoride and bromide), sulfate, total nitrogen, and stable isotopes (18O2H, and 34S) behaved quite conservatively. Boron, residual alkalinity, EDTA and Zn did not. Yet, including these species in the computations did not affect significantly the proportion estimations.

Vázquez-Suñé, E.; Carrera, J.; Tubau, I.; Sánchez-Vila, X.; Soler, A.

2010-04-01

38

A Dimensionless Parameter Study of Groundwater Recharge.  

National Technical Information Service (NTIS)

The method of coefficients has been used to predict groundwater recharge for several years. A new approach was attempted using a 'dimensionless parameter' concept to relate recharge to other known parameters, i.e., pumpage, permeability, rainfall, recharg...

G. A. Coleman J. K. Cheng J. F. Harp J. G. Laguros

1972-01-01

39

Universal connector for rechargeable and non-rechargeable batteries  

SciTech Connect

In an electrical product having battery recharging means and a load adapted for energization from a battery, a battery connector is described which consists of: terminal means adapted to contact the output terminals of either a non-rechargeable battery having a first physical configuration or a rechargeable battery having a second physical configuration, the terminal means coupled to the load of the product such that the load may be energized from either the non-rechargeable battery or the rechargeable battery; circuit means coupling the terminal means and the battery recharging means, the circuit means including a switch having an open state preventing charging through the circuit means of a battery coupled to the terminal means and a closed state permitting charging through the circuit means of a battery coupled to the terminal means; and biased actuating means coupled to the switch for moving the switch between its closed and open sites, the actuating means adapted to coact with the first physical configuration of a non-rechargeable battery to move the switch against a bias to its open state and adapted to coact with the second physical configuration of a rechargeable battery to allow the switch to move with the bias to its closed state; whereby the physical configurations of a battery connected to the battery connector determines whether or not the battery will be charged.

Mundschenk, G.R.; Decker, R.C.

1986-07-22

40

Fuel-Powered Artificial Muscles  

Microsoft Academic Search

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

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

2006-01-01

41

Novel rechargeable sodium batteries  

Microsoft Academic Search

The program was concerned with the development of a high energy density rechargeable sodium battery operating in the moderate temperature range of 175 to 200 C. The suitability of NaFeOâ and FeOCl as cathode materials in Na cells having the configuration--Molten Na\\/beta-AlâOâ\\/Molten NaAlC{sub l4}, NaFeOâ or FeOC{sub l}--has been studied. Cells containing either NaFeOâ or FeOCl were found to cycle

1988-01-01

42

Recharging of contaminated aquifer with reclaimed sewage water  

NASA Astrophysics Data System (ADS)

About 40% of the water supply of Cairo, Egypt, is drawn from a groundwater reservoir located southeast of the Nile Delta. Several thousand shallow wells supply drinking water to the farmers from the same groundwater reservoir, which is recharged by seepage from Ismailia canal, the irrigation canal network, and other wastewater lagoons in the same areas. Sewage water lagoons were located at the high ground of the area, recharging contaminated water into the aquifer. Since the groundwater in this area is used for drinking purposes, it was decided to treat the sewage water recharging the aquifer for health reasons. In this paper a solution to the problem is presented using an injection well recharging good quality water into the aquifer. A pumping well located at a distance downstream is used to pump the contaminated water out of the aquifer. A three-dimensional solute transport model was developed to study the concentration distribution with remediation time in the contaminated zone.

Soliman, M. M.; El-Din, M. Nour; Hassan, N. A.

1995-04-01

43

High Power Rechargeable Thermal Battery.  

National Technical Information Service (NTIS)

Report developed under STTR contract; a proof of concept for a portable, rechargeable thermal battery (RTB). Including a superinsulated case, a lightweight (10 lb) RTB can provide 250W for 2-6h at 140 Wh/kg with days of activation between recharging. It c...

T. D. Kaun

1997-01-01

44

Issue and challenges facing rechargeable thin film lithium batteries  

Microsoft Academic Search

New materials hold the key to fundamental advances in energy conversion and storage, both of which are vital in order to meet the challenge of global warming and the finite nature of fossil fuels. Nanomaterials in particular offer unique properties or combinations of properties as electrodes and electrolytes in a range of energy devices. Technological improvements in rechargeable solid-state batteries

Arun Patil; Vaishali Patil; Dong Wook Shin; Ji-Won Choi; Dong-Soo Paik; Seok-Jin Yoon

2008-01-01

45

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

NASA Astrophysics Data System (ADS)

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.

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

2013-10-01

46

Water recharge in Larderello Geothermal field  

SciTech Connect

In this paper, the variations in fluid composition observed in area of Larderello field that are strongly affected by induced recharge are ascribed to a simple mechanism, and a comprehensive conceptual model is presented for these areas. According to out interpretation, the steam produced in areas affected by induced recharge is a mixture of two components (steam from recharge water and original deep steam). The natural recharge increased and recharge became an important phenomenon as a consequence of the pressure drawdown caused by exploitation. Three separate estimates of the water recharge give similar results and confirm that a significant fraction of the produced steam derives from recharge water.

Celati, R.; Calore, C.; Grassi, S.; D'Amore, F. (CNR International Int. for Geothermal Research, Piazza Solferino 2, 56126 Pisa (IT)); Cappetti, G. (ENEL Vice-Direction of Geothermal Activity, Via Andrea Pisano 120, 56122 Pisa (IT))

1991-01-01

47

Problems of Heat Transfer within the Containing Vessel of High Performance LMFBR Spent Fuel Shipping Casks.  

National Technical Information Service (NTIS)

A preliminary assessment of heat transfer problems internal to a LMFBR spent fuel shipping cask is reported. The assessment is based upon previous results obtained in full-scale, electrically heated mockups of an LMFBR assembly located in a containing pip...

R. B. Pope D. K. Gartling W. P. Schimmel D. W. Larson

1976-01-01

48

Problems of heat transfer within the containing vessel of high performance LMFBR spent fuel shipping casks  

Microsoft Academic Search

A preliminary assessment of heat transfer problems internal to a LMFBR spent fuel shipping cask is reported. The assessment is based upon previous results obtained in full-scale, electrically heated mockups of an LMFBR assembly located in a containing pipe, and also upon analytical and empirical studies presented in this paper. It is shown that a liquid coolant will be required

R. B. Pope; D. K. Gartling; W. P. Jr. Schimmel; D. W. Larson

1976-01-01

49

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

ERIC Educational Resources Information Center

|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…

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

2009-01-01

50

Rechargeable natrium batteries. (Genopladelige natriumbatterier).  

National Technical Information Service (NTIS)

Investigations on rechargeable molten salt batteries have been carried out. Molten chloride aluminates have been used as electrolytes, and aluminium as anodes, the cathodes have often been transient metal sulphides. Furthermore, investigations on natrium ...

H. Hjuler B. C. Knutz B. Vestergaard N. J. Bjerrum

1992-01-01

51

Apparatus for charging rechargeable battery  

SciTech Connect

A rechargeable battery is supplied with a charging voltage from a charging voltage source and exhibits a charging voltage characteristic having a peak shortly before the rechargeable battery reaches a fully charged state. A resistor voltage dividing circuit having a plurality of voltage output terminals is connected to both terminals of the rechargeable battery. A voltage memory device is provided for storing a predetermined voltage based on a voltage supplied from the voltage dividing circuit corresponding to the peak point of the charging voltage characteristic and comparison is made of the other output voltage obtained from the voltage dividing circuit after the peak point is passed and the stored voltage in the voltage memory device and a supply of a charging power from the charging voltage source to the rechargeable battery is interrupted when the difference between these voltages becomes zero.

Oyamada, K.; Tada, K.

1982-10-12

52

Electrically Rechargeable Redox Flow Cell.  

National Technical Information Service (NTIS)

A bulk energy storage system is described. The system includes an electrically rechargeable reduction-oxidation cell divided by a membrane into two compartments, each containing an electrode. An anode fluid is directed through the first compartment at the...

L. H. Thaller

1975-01-01

53

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

NASA Astrophysics Data System (ADS)

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.

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

2012-10-01

54

Experiences of realisation and test of a fuel-cell based vehicle  

Microsoft Academic Search

Electric vehicles are an important option to reduce pollution and greenhouse effect in the environment. The main problems for battery fed electric vehicles are related to the small ranges, and large recharging times. A possible solution is constituted by electric vehicles in which the energy is produced on-board by a fuel cell based electricity generator. This paper reports about some

M. Ceraolo; G. Lutzemberger; N. Doveri

2010-01-01

55

Novel rechargeable sodium batteries  

SciTech Connect

The program was concerned with the development of a high energy density rechargeable sodium battery operating in the moderate temperature range of 175 to 200 C. The suitability of NaFeO{sub 2} and FeOCl as cathode materials in Na cells having the configuration--Molten Na/beta-Al{sub 2}O{sub 3}/Molten NaAlC{sub l4}, NaFeO{sub 2} or FeOC{sub l}--has been studied. Cells containing either NaFeO{sub 2} or FeOCl were found to cycle about 3 Na per Fe reversibly, in a two step discharge. The voltage profiles of cells containing either of these materials are strikingly similar. Chemical reactions between the NaAlC{sub l4} electrolyte and NaFeO{sub 2} or FeOCl have been proposed which suggest the formation of the identical intermediate in cells of either type. The quasi-theoretical specific energy is 1545 Wh/kg for the Na/NaFeO{sub 2} couple, and 1475 Wh/kg for the Na/FeOCl cell. When the possible involvement of one mole of NaAlCl4 in the discharge reaction is considered, these values become 628 Wh/kg for the former, and 603 Wh/kg for the latter.

Abraham, K.M.

1988-07-28

56

Early evaluation of a rechargeable pacemaker system.  

PubMed

A rechargeable demand pulse generator for permanent transvenous cardiac pacing was evaluated in 66 patients. During a cumulative follow-up period of 895 patient months there was no instance of failure of either the pulse generator or of the recharging circuit. Acceptance of the recharging concept was high, there being only one patient in whom it was necessary to replace the rechargeable generator because of inability to master the recharging technique. The early findings indicate that with proper patient selection the rechargeable pulse generator promises to be an important contribution to pacemaker therapy. PMID:978092

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

1976-01-01

57

Carbon materials for lithium-ion rechargeable batteries  

Microsoft Academic Search

The recent development of lithium rechargeable batteries results from the use of carbon materials as lithium reservoir at the negative electrode. Reversible intercalation, or insertion, of lithium into the carbon host lattice avoids the problem of lithium dendrite formation and provides large improvement in terms of cycleability and safety. This paper reviews the main achievements on performance and understanding of

S. Flandrois; B. Simon

1999-01-01

58

Functional materials for rechargeable batteries.  

PubMed

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

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

2011-03-11

59

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

SciTech Connect

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.

Lin, Zhenhong [ORNL; Greene, David L [ORNL

2012-01-01

60

High Plains States Groundwater Demonstration Program. Rillito Recharge Project Artificial Groundwater Recharge Project Artificial Groundwater Recharge Demonstration Project Summary.  

National Technical Information Service (NTIS)

This report summarizes the development, conduct, and findings of the Rillito Recharge Project. Detailed information can be found in the Final Report: Rillito Recharge Project. The project is one of 13 demonstration projects by the Bureau of Reclamation (R...

1996-01-01

61

Plasma ignition of combustion in a supersonic flow of fuel-air mixtures: Simulation problems  

Microsoft Academic Search

Theoretical and experimental approaches to tackling the problems of plasma ignition of supersonic combustion in fuel-air mixtures\\u000a of various compositions are discussed. Discharge types useful for this purpose are considered. The feasibility of reaching\\u000a a substantial gain in energy in the initiation of combustion by non-equilibrium gas-discharge plasma is particularly interesting.

I. V. Kochetov; A. P. Napartovich; S. B. Leonov

2006-01-01

62

A new method for mapping groundwater recharge areas and for zoning recharge for an inverse model  

Microsoft Academic Search

This thesis presents a new methodology for delineating groundwater recharge and discharge areas. Estimates of recharge rates and locations of recharge areas are important components in strategies for managing groundwater resources. The main contribution of this thesis is a method for zoning recharge for parameter-estimation (inverse) models. The importance of the zoning method presented here is that it is objective,

Stoertz

1989-01-01

63

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

SciTech Connect

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)

Yang, W. [Shanghai Nuclear Engineering Research and Design Inst., Hong Cao road 29, Shanghai (China); Dept. of Nuclear Engineering, Xi'an Jiaotong Univ., Xian Ning west road 28, Xi'an, Shaanxi (China); Wu, H.; Cao, L. [Dept. of Nuclear Engineering, Xi'an Jiaotong Univ., Xian Ning west road 28, Xi'an, Shaanxi (China)

2012-07-01

64

Discharging and recharging of anomalous positive charges in MOSFETs  

Microsoft Academic Search

The discharging of positive charges is found to increase with bias. Following the same discharging, higher recharging bias leads to larger recharging of APC. However, under the same recharging bias with different previous discharging, the recharging does show a different response. In particular, there is larger recharging after the larger previous discharging, whatever the same recharging bias

Yongjun Wu; Mingzhen Xu; Changhua Tan; Jianlin Wei; Yi Liang; Yangyuan Wang

1998-01-01

65

Solid polymer electrolytes for rechargeable batteries  

NASA Astrophysics Data System (ADS)

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 tetraethylorthosilicate (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 x 10(exp -4) S cm(exp -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.

Narang, Subhash C.; Ventura, Susanna C.

1992-02-01

66

Water recharge in Larderello Geothermal field  

Microsoft Academic Search

In this paper, the variations in fluid composition observed in area of Larderello field that are strongly affected by induced recharge are ascribed to a simple mechanism, and a comprehensive conceptual model is presented for these areas. According to out interpretation, the steam produced in areas affected by induced recharge is a mixture of two components (steam from recharge water

R. Celati; C. Calore; S. Grassi; F. DAmore; G. Cappetti

1991-01-01

67

Reusable Energy and Power Sources: Rechargeable Batteries  

ERIC Educational Resources Information Center

|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…

Hsiung, Steve C.; Ritz, John M.

2007-01-01

68

Apparatus for successively charging rechargeable batteries  

Microsoft Academic Search

A charging apparatus charges a plurality of rechargeable batteries individually and in succession. Each of the plurality of rechargeable batteries is coupled to one corresponding charging branch. The charging apparatus comprises a charging completion detecting circuit for detecting a charging completion of a rechargeable battery now in a charging operation, a high voltage detecting circuit for detecting an abnormal voltage

K. Matsuura; K. Oyamada

1983-01-01

69

Manganese oxide cathodes for rechargeable batteries  

Microsoft Academic Search

Manganese oxides are considered as promising cathodes for rechargeable batteries due to their low cost and low toxicity as well as the abundant natural resources. In this dissertation, manganese oxides have been investigated as cathodes for both rechargeable lithium and alkaline batteries. Nanostructured lithium manganese oxides designed for rechargeable lithium cells have been synthesized by reducing lithium permanganate with methanol

Dongmin Im

2002-01-01

70

Rechargeable lithium polymer electrolyte batteries  

Microsoft Academic Search

Rechargeable lithium polymer electrolyte batteries have been under development for over ten years. The organic electrolyte has a low-vapor pressure and, in principle, during times of abuse, will be safe with respect to volatilization, ignition, and explosion. The electrolyte can be fabricated in the form of a thin solid film so no other separator element is required. Thus, the very

Boone B. Owens

1992-01-01

71

Prototype systems for rechargeable magnesium batteries.  

PubMed

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

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

2000-10-12

72

State of the art of multi-fuel reformers for fuel cell vehicles: problem identification and research needs  

Microsoft Academic Search

This review is focused on discussions about multi-fuel reformer technology for fuel cell vehicles where techniques for onboard hydrogen generation and gas clean-up processes, as well as fuel considerations and emissions are included. Our conclusion is that the potential for developing a highly efficient, durable and reliable reformer system for automotive applications is considerably higher if dedicated fuel reformers are

Lars J Pettersson; Roger Westerholm

2001-01-01

73

Applications of genetic algorithms to optimization problems in the solvent extraction process for spent nuclear fuel  

SciTech Connect

Applications of genetic algorithms (GAs) to optimization problems in the solvent extraction process for spent nuclear fuel are described. Genetic algorithms have been considered a promising tool for use in solving optimization problems in complicated and nonlinear systems because they require no derivatives of the objective function. In addition, they have the ability to treat a set of many possible solutions and consider multiple objectives simultaneously, so they can calculate many pareto optimal points on the trade-off curve between the competing objectives in a single iteration, which leads to small computing time. Genetic algorithms were applied to two optimization problems. First, process variables in the partitioning process were optimized using a weighted objective function. It was observed that the average fitness of a generation increased steadily as the generation proceeded and satisfactory solutions were obtained in all cases, which means that GAs are an appropriate method to obtain such an optimization. Secondly, GAs were applied to a multiobjective optimization problem in the co-decontamination process, and the trade-off curve between the loss of uranium and the solvent flow rate was successfully obtained. For both optimization problems, CPU time with the present method was estimated to be several tens of times smaller than with the random search method.

Omori, Ryota, Sakakibara, Yasushi; Suzuki, Atsuyuki [Univ. of Tokyo (Japan). Dept. of Quantum Engineering and Systems Science

1997-04-01

74

Current and Future Problems of the Fuel Supply for Nuclear Power  

Microsoft Academic Search

The structure of the nuclear fuel cycle, consisting of the technological stages of uranium production, refining, enrichment, fabrication of nuclear fuel, and reprocessing of the spent fuel for reuse of the fissioning materials, is examined. Supplying fuel includes supplying fuel for Russian nuclear power plants, propulsion and research reactors, export of fuel for nuclear power plants and research reactors constructed

M. I. Solonin; I. I. Konovalov

2003-01-01

75

Light aircraft engines, the potential and problems for use of automotive fuels. Phase I. Literature search. Final report, October 1979-September 1980  

SciTech Connect

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.

Patterson, D.J.; Morrison, K.; Remondino, M.; Slopsema, T.

1980-12-01

76

Microbial problems in connection with storage of jet fuel in rock caverns. Methods to inhibit development of corrosive fuel. Mikrobiella problem vid bergrumslagring av jetbraensle. Inhiberingsmetoder foer att foerhindra uppkomst av korrosivt braensle  

SciTech Connect

Problems with long-term storage of jet fuel in rock caverns have during the last years been observed. The problems have mainly been concerned with the accumulation of corrosive compounds in the fuel. Studies in laboratory model systems were carried out in order to understand which factors are important in causing the problems. The rate of groundwater leaking in, the oxygen and sulfate concentration in the bedwater, the amount of sediment, and the temperature were shown to be some of the more-important factors. With the aim to find some suitable methods to prevent the problems from arising, studies in model systems were also carried out. Oxygenation of the bedwater or addition of a biodegradable biocide gave positive effects resulting in reduction of microbial activities and no development of corrosive fuel.

Norqvist, A.; Edlund, A.; Roffey

1986-04-01

77

Groundwater recharge and agricultural contamination  

USGS Publications Warehouse

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.

Bohlke, J. -K.

2002-01-01

78

Groundwater recharge and agricultural contamination  

NASA Astrophysics Data System (ADS)

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. Agricultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO3 -, N2, Cl, SO4 2-, H+, P, C, K, Mg, Ca, Sr, Ba, Ra, and As, as well as 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.

Böhlke, John-Karl

2002-02-01

79

Multilevel Multisensor-Based Intelligent Recharging System for Mobile Robot  

Microsoft Academic Search

Based on the sensor-based detection method, this paper presents an intelligent recharging system for a mobile robot. First, we design a flexible and reasonable intelligent recharging system for the mobile robot. It consists of a recharging station, a recharging device, and an intelligent power-detection module. The recharging station is designed to have 2 DOFs, such that it can move along

Ren C. Luo; Kuo L. Su

2008-01-01

80

Choosing appropriate techniques for quantifying groundwater recharge  

NASA Astrophysics Data System (ADS)

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. Résumé. Il existe différentes techniques pour quantifier la recharge; toutefois, il est souvent difficile de choisir les techniques appropriées. Les points importants pour le choix d'une technique sont l'échelle de temps et d'espace, la gamme de valeurs et la validité des estimations de la recharge basées sur différentes techniques; d'autres facteurs peuvent limiter l'application de techniques particulières. Le but des études de la recharge est important parce qu'il peut imposer les échelles de temps et d'espace des estimations de recharge. Les buts de ces études concernent habituellement l'évaluation des ressources en eau, qui requiert des informations sur la recharge à des échelles spatiales étendues et sur des durées comptées en dizaines d'années, et l'évaluation de la vulnérabilité des aquifères aux contaminations, qui exige des informations détaillées sur la variabilité spatiale et les écoulements préférentiels. La gamme des taux de recharge qui peuvent être estimés par différentes approches doit être adaptée aux valeurs attendues de la recharge sur le site. La validité des estimations de recharge faites par des techniques différentes est variable. Des techniques s'appuyant sur des données concernant les eaux de surface et la zone non saturée fournissent des estimations de recharge potentielle, tandis que celles basées sur les données des eaux souterraines donnent généralement des estimations de la recharge réelle. Les incertitudes de chaque approche d'estimation de la recharge mettent en relief la nécessité d'appliquer des techniques multiples pour accroître la validité des estimations de la recharge. Resumen. Existen diversas técnicas para cuantificar la recarga, pero elegir las apropiadas es a menudo difícil. Entre las consideraciones a tener en cuenta, hay que citar las escalas espacial y temporal, el rango y la fiabilidad de las estimaciones de la recarga obtenidas por medio de técnicas diferentes; hay otros factores que pueden limitar la aplicación de técnicas particulares. El objetivo de un estudio de recarga es importante, ya que puede condicionar las escalas temporal y espacial de las estimaciones. Los objetivos típicos comprenden la evaluación de recursos, cosa que requiere información de la recarga para escalas espaciales extensas y escalas temporales cifradas en décadas, y la evaluación de la vulnerabilidad del acuífero a la contaminación, para lo que hace falta información detallada sobre la variabilidad espacial y el flujo preferente. Se debería contrastar el rango de los valores estimados de recarga mediante enfoques diferentes con los valores esperados en un emplazamiento. La fiabilidad de las estimaciones basadas en técnicas diferentes es variable. Así, la

Scanlon, Bridget; Healy, Richard; Cook, Peter

2002-01-01

81

Evaluation of a rechargeable pacemaker system.  

PubMed

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

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

1978-04-01

82

Choosing appropriate techniques for quantifying groundwater recharge  

Microsoft Academic Search

.   Various techniques are available to quantify recharge; however, choosing appropriate techniques is often difficult. Important\\u000a considerations in choosing a technique include space\\/time scales, range, and reliability of recharge estimates based on different\\u000a techniques; other factors may limit the application of particular techniques. The goal of the recharge study is important\\u000a because it may dictate the required space\\/time scales of

Bridget R. Scanlon; Richard W. Healy; Peter G. Cook

2002-01-01

83

Using groundwater levels to estimate recharge  

Microsoft Academic Search

.   Accurate estimation of groundwater recharge is extremely important for proper management of groundwater systems. Many different\\u000a approaches exist for estimating recharge. This paper presents a review of methods that are based on groundwater-level data.\\u000a The water-table fluctuation method may be the most widely used technique for estimating recharge; it requires knowledge of\\u000a specific yield and changes in water levels

Richard W. Healy; Peter G. Cook

2002-01-01

84

Identifying and quantifying urban recharge: a review  

Microsoft Academic Search

.   The sources of and pathways for groundwater recharge in urban areas are more numerous and complex than in rural environments.\\u000a Buildings, roads, and other surface infrastructure combine with man-made drainage networks to change the pathways for precipitation.\\u000a Some direct recharge is lost, but additional recharge can occur from storm drainage systems. Large amounts of water are imported\\u000a into most

David N. Lerner

2002-01-01

85

Variability in simulated recharge using different GCMs  

NASA Astrophysics Data System (ADS)

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.

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

2010-10-01

86

System for charging a rechargeable battery  

SciTech Connect

This patent describes, for use in an energy-using device adapted to operate from an external source of A-C power and from either rechargeable type or non-rechargeable type batteries of the same standard size and configuration, a charging system comprising in combination: a housing for the energy-using device. The energy-using device is operable in a first mode when connected to the external source of A-C power to supply the A-C power to a load disposed within the energy-using device and to recharge the rechargeable battery type and in a second mode when disconnected from the source of A-C power to supply power to the load alternatively from the rechargeable or non-rechargeable battery types; and electrical charging circuit disposed within the housing of the energy-using device for charging the rechargeable battery type when the energy-using device is connected to the external source of A-C power; and a cavity disposed within the housing of the energy-using device for alternatively receiving therein batteries of both of the rechargeable and non-rechargeable types. Each of the types has a positive power terminal and a negative power terminal for providing electrical energy from the battery types to the energy-using device.

Scholefield, C.L.

1986-12-09

87

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

SciTech Connect

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.

Dirk, G. [Rhenipal UK Ltd., Birkenhead (United Kingdom)

1996-12-31

88

Identifying Recharge Location Using Noble Gas Recharge Temperatures, Pajarito Plateau, New Mexico  

NASA Astrophysics Data System (ADS)

The solubility of noble gases in water is temperature dependent. Noble gas concentrations in ground water can therefore be used to determine the temperature at the water table at the recharge location (recharge temperature). The Pajarito Plateau in Northern New Mexico is an example of a hydrogeologic setting where noble gas recharge temperatures provide valuable information about recharge location which could be utilized in numerical model calibration. Previous studies have identified two potentially significant components of recharge to the regional aquifer underlying the plateau: (1) infiltration of precipitation in the Jemez Mountains adjacent to the plateau (mountain-block recharge); and (2) infiltration of stream water in the bottoms of canyons that traverse the plateau (plateau recharge). However, results regarding the relative importance of these two components are conflicting and uncertain. Their relative magnitude is of particular concern because Los Alamos National Laboratory is located on the plateau, and the susceptibility of the regional aquifer to lab-generated wastes depends directly upon the amount of plateau recharge. The Pajarito Plateau is an ideal location for applying noble gas recharge thermometry; mountain-block recharge should have cool recharge temperatures (<12°C) due to the shallow water table in the mountains, whereas plateau recharge should have distinctly warmer recharge temperatures (18 to 21°C) due to water table depths of 200 to 300m on the plateau. Noble gas samples were collected from wells screened in the regional aquifer across the plateau. Those analyzed to date from wells screened in the upper 30m of the aquifer yield recharge temperatures of 18 to 23°C. Exceptions are two wells located within 2km of the mountain front, which have recharge temperatures of 12 and 13°C. The one sample analyzed to date from a well screened deeper in the aquifer (125m below the water table) yields a recharge temperature of 11°C. Preliminary results therefore suggest that plateau recharge comprises nearly all of the water in the upper 30m of the regional aquifer throughout much of the plateau. However, the cooler recharge temperatures closer to the mountains and at depth indicate that mountain-block recharge may still constitute most of the total recharge to the aquifer; plateau recharge may be limited to a thin layer along the top of the aquifer at distances >2km from the mountain front.

Manning, A. H.; Dale, M.

2008-12-01

89

Expanded use of fossil fuels by the U. S. and the global carbon dioxide problem  

SciTech Connect

Continued combustion of fossil fuels contributes to a steady increase of carbon dioxide concentration in the atmosphere. Projecting present increases in rates of fossil-fuel utilization, a doubling of CO/sub 2/ concentration in the atmosphere may be expected within the next 75 years. Based on preliminary calculations, coal utilization by the U.S. to the year 2020 accounts for between 9 and 14% of the increase in CO/sub 2/ concentration. Carbon dioxide in the atmosphere absorbs infrared radiation, causing an increase in the surface temperature of the earth. The most recent climatic models indicate that each doubling in atmospheric CO/sub 2/ concentration will result in a temperature increase of approximately 3 +- 1/sup 0/C, depending on the model used. Changes in average rates of precipitation and evaporation may follow, leading to higher probabilities of drought in the mid-latitudes (including the (U.S.). Manabe and Wetherald (J. Atmos. Sci., 32: 3-15 (1975)) have estimated the temperature increase at high latitudes to be three times the increase in the global average surface temperature. Large-scale melting of the polar ice caps and a subsequent increase in the surface area of the oceans may follow on a timetable that is not yet clear. The distribution of vegetation and agricultural activities can be expected to change in response to the temperature increase and associated with the analysis of the CO/sub 2//climate problem mandate the initiation of an immediate global-scale interdisciplinary research effort to determine more clearly the components and connections of the problem and to develop strategies for reducing the impacts, i.e., contingency plans that could be helpful regardless of impact details which remain to be determined. 26 references.

Emanuel, W.R.; Olson, J.S.; Killough, G.G.

1980-01-01

90

State of the art in LP-Gas fueling systems and problems for motor fuel, forklift, and recreational vehicle bottle filling  

Microsoft Academic Search

Major problem areas of LP-Gas dispensing systems relate to deficiencies in existing systems, improper fuel transfer practices, customer service standards, failure to observe regulations and codes, and education and training of personnel handling transfer of LP-Gas. The state of the art is at a point where engineering and technical deficiencies of existing dispensing systems can be corrected satisfactorily in most

Carnahan

1973-01-01

91

Used oil as an alternative boiler fuel-promises and problems  

Microsoft Academic Search

The authors examine used oil as a boiler fuel, comparing the properties of used oil fuel with fuel oil and addressing environmental concerns. Availability and cost factors are investigated, and savings available to a medium-sized municipal utility are evaluated. Of special concern to that utility and to others considering the used oil fuel as an alternative are the modifications required

E. Menge; K. Nicholson

1993-01-01

92

Issue and challenges facing rechargeable thin film lithium batteries  

SciTech Connect

New materials hold the key to fundamental advances in energy conversion and storage, both of which are vital in order to meet the challenge of global warming and the finite nature of fossil fuels. Nanomaterials in particular offer unique properties or combinations of properties as electrodes and electrolytes in a range of energy devices. Technological improvements in rechargeable solid-state batteries are being driven by an ever-increasing demand for portable electronic devices. Lithium batteries are the systems of choice, offering high energy density, flexible, lightweight design and longer lifespan than comparable battery technologies. We present a brief historical review of the development of lithium-based thin film rechargeable batteries highlight ongoing research strategies and discuss the challenges that remain regarding the discovery of nanomaterials as electrolytes and electrodes for lithium batteries also this article describes the possible evolution of lithium technology and evaluates the expected improvements, arising from new materials to cell technology. New active materials under investigation and electrode process improvements may allow an ultimate final energy density of more than 500 Wh/L and 200 Wh/kg, in the next 5-6 years, while maintaining sufficient power densities. A new rechargeable battery technology cannot be foreseen today that surpasses this. This report will provide key performance results for thin film batteries and highlight recent advances in their development.

Patil, Arun; Patil, Vaishali; Shin, Dong Wook; Choi, Ji-Won; Paik, Dong-Soo [Thin Film Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Yoon, Seok-Jin [Thin Film Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of)], E-mail: sjyoon@kist.re.kr

2008-08-04

93

NORTH CAROLINA GROUNDWATER RECHARGE RATES 1994  

EPA Science Inventory

North Carolina Groundwater Recharge Rates, from Heath, R.C., 1994, Ground-water recharge in North Carolina: North Carolina State University, as prepared for the NC Department of Environment, Health and Natural Resources (NC DEHNR) Division of Enviromental Management Groundwater S...

94

Reflections on Dry-Zone Recharge  

NASA Astrophysics Data System (ADS)

Quantifying recharge in regions of low precipitation remains a challenging task. The design of permanent nuclear-waste isolation at Yucca Mountain, Nevada, the design of arid-site landfill covers and the pumping of groundwater in desert cities, like Las Vegas, are examples where accurate recharge estimates are needed because they affect billion-dollar decisions. Recharge cannot be measured directly and must rely on estimation methods of various kinds including chemical tracers, thermal profiling, lysimetry, and water-balance modeling. Chemical methods, like chloride-mass-balance can significantly underestimate actual recharge rates and water-balance models are generally limited by large uncertainties. Studies at the U. S. Department of Energy's Hanford Site in Washington State, USA illustrate how estimates of recharge rates have changed over time and how these estimates can affect waste management decisions. Lysimetry has provided reliable estimates of recharge for a wide range of surface condittions. Lysimetric observations of reduced recharge, resulting from advective drying of coarse rock piles, suggest a way to avoid costly recharge protection using titanium shields at Yucca Mountain. The Pacific Northwest National Laboratory is funded by the U. S. Department of Energy under contract DE-AC05-76-RL01830.

Gee, G. W.

2005-05-01

95

Transformer Recharging with Alpha Channeling in Tokamaks  

SciTech Connect

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. __________________________________________________

N.J. Fisch

2009-12-21

96

Transformer Recharging with Alpha Channeling in Tokamaks.  

National Technical Information Service (NTIS)

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 i...

N. J. Fisch

2009-01-01

97

Application of the RBD (Rechargement-Brasage-Diffusion) Process to the Deposition of Anti-Wear Alloys.  

National Technical Information Service (NTIS)

Initially, the rechargement-brasage-diffusion (RBD) was developed by SNECMA to solve problems occurring during assembly and repair of cast superalloy turbine parts. Beyond the metallurgical possibilities it offers, this process has proved to be economical...

J. Lesgourgues

1986-01-01

98

Cycle-life sensor for rechargeable lithium batteries. Phase 1  

SciTech Connect

The research addressed the problem of characterizing the state of a rechargeable Li battery as a function of cycle life history. Because all Li batteries are hermetically sealed, researchers chose to evaluate the amount and distribution of Li-electrolyte degradation products in situ by the application of electroanalytical techniques at microelectrodes imbedded in the cell package. Good correlations between Li stripping currents and cycle life were achieved in Li/Li half cells. However, when the electroanalytical technique was employed in Li/TiS2 full cells, no systematic trend was found. Moreover, Li-electrolyte degradation products were found to be either insoluble or electroinactive over the available electrochemical window. Thus, this approach to predicting rechargeable Li battery cycle life has no commercial utility.

Koch, V.R.

1988-08-15

99

Biomaterials immobilized with chitosan for rechargeable antimicrobial drug delivery.  

PubMed

Microbial contamination on medical device material surfaces causes serious problems including device-related infections. Here we report a new strategy to produce rechargeable antimicrobial biomaterial surfaces to address the issue. Methacrylic acid (MAA) was grafted onto the surfaces of polyurethane (PU), a widely used biomaterial with excellent biological and mechanical properties. Chitosan was covalently bonded onto the MAA-grafted surfaces. The new chitosan-containing PU strongly bound and then slowed release anionic antibiotics (e.g., rifampin) for weeks to months to kill microbes. The released drug could be recharged with the same or a different class of drugs to further extend antimicrobial duration. Also, the new surfaces demonstrated good biocompatibility against mammal cells, pointing to great potentials for a wide range of biomedical applications. PMID:22865542

Lv, Wei; Luo, Jie; Deng, Ying; Sun, Yuyu

2012-08-03

100

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

SciTech Connect

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.

Prayudhatama, D.; Waris, A.; Kurniasih, N.; Kurniadi, R. [Bosscha Laboratory, Department of Physics, Nuclear Physics and Biophysics Research Group, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung (Indonesia)

2010-06-22

101

Some Research Pertaining to the Problem of Predicting the Burning Rate of Cellulosic Fuels.  

National Technical Information Service (NTIS)

Contents: Papers- Heat transfer effect in the transient pyrolysis of cellulose slabs; some effects of size, orientation, and fuel molecular weight on the burning of fuel soaked wicks; the influence of internal convection on the transient pyrolysis of cell...

P. L. Blackshear K. A. Murty N. Murayama

1965-01-01

102

Multi-robot, multi-rendezvous recharging paradigm: An opportunistic control strategy  

Microsoft Academic Search

This paper presents an opportunistic control ap- proach to address the multi-robot, multi-rendezvous recharging problem. The control strategy adapted attempts to take advan- tages of both centralized as well as distributed methodologies while addressing the problem. Every robotic agent of the group is equipped with a decision engine that scores available rendezvous locations that are obtained via communicating with mother

Soheil Keshmiri

2011-01-01

103

Expanded use of fossil fuels by the US and the global carbon dioxide problem  

SciTech Connect

Projecting present increases in rates of fossil fuel utilization, a doubling of CO/sub 2/ concentration in the atmosphere may be expected within the next 75 years. Based on preliminary calculations, coal utilization by the United States to the year 2020 accounts for between 9 and 15% of the increase in CO/sub 2/ concentration. Carbon dioxide in the atmosphere absorbs infra-red radiation, causing an increase in the surface temperature of the earth. The most recent climatic models indicate that each doubling in atmospheric CO/sub 2/ concentration will result in a temperature increase of approximately 3 +- 1/sup 0/C, depending on the model used. Changes in average rates of precipitation and evaporation may follow, leading to higher probabilities of drought in the mid-latitudes (including the United States). Manabe and Wetherald (1975) have estimated the temperature increase at high latitudes to be three times the increase in the global average surface temperature. Large-scale melting of the polar ice caps and a subsequent increase in the surface area of the oceans may follow on a timetable that is not yet clear. The distribution of vegetation and agricultural activities can be expected to change in response to the temperature increase and associated changes in precipitation and evaporation. The many uncertainties associated with the analysis of the carbon dioxide/climate problem mandate the initiation of an immediate global-scale interdisciplinary research effort to determine more clearly the components and connections of the problem and to develop strategies for reducing the impacts, i.e., contingency plans that could be helpful regardless of impact details which remain to be determined.

Emanuel, W.R.; Olson, J.S.; Gillough, G.G.

1980-01-01

104

Lithium ion rechargeable systems studies  

SciTech Connect

Lithium ion systems, although relatively new, have attracted much interest worldwide. Their high energy density, long cycle life and relative safety, compared with metallic lithium rechargeable systems, make them prime candidates for powering portable electronic equipment. Although lithium ion cells are presently used in a few consumer devices, e.g., portable phones, camcorders, and laptop computers, there is room for considerable improvement in their performance. Specific areas that need to be addressed include: (1) carbon anode--increase reversible capacity, and minimize passivation; (2) cathode--extend cycle life, improve rate capability, and increase capacity. There are several programs ongoing at Sandia National Laboratories which are investigating means of achieving the stated objectives in these specific areas. This paper will review these programs.

Levy, S.C.; Lasasse, R.R.; Cygan, R.T.; Voigt, J.A.

1995-02-01

105

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

SciTech Connect

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.

King, J.M. Jr.

1996-03-01

106

Battery charging system including means for distinguishing between rechargeable and non-rechargeable batteries  

SciTech Connect

A battery charging system adapted to distinguish a rechargeable battery type from a non-rechargeable battery type is described, both types being of substantially similar size and having first and second external load terminals for delivering electrical energy. The system consists of: a battery charging circuit having a first non-charging mode and a second charging mode, the circuit having first and second charging contacts arranged for engagement with the first and second external load terminals respectively of when a battery is connected to the contacts; sensing means for sensing the value of at least one parameter common to both rechargeable and non-rechargeable batteries, the value for a rechargeable battery differing from the value for a non-rechangeable battery; enabling means responsive to the sensing means for disabling the charging circuit when the value is indicative of a non-rechargeable battery.

Hodgman, J.S.; Mullersman, F.H.

1986-03-18

107

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

Microsoft Academic Search

Sophocleous, M. and Perry, C.A., 1985. Experimental studies in natural groundwater- recharge dynamics: The analysis of observed recharge events. J. Hydrol., 81 : 297--332. 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

MARIOS SOPHOCLEOUS; CHARLES A. PERRY

1985-01-01

108

Advanced rechargeable sodium batteries with novel cathodes  

NASA Astrophysics Data System (ADS)

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.

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

1989-12-01

109

Electrolyte for laminated polymer lithium rechargeable battery  

NASA Astrophysics Data System (ADS)

Proposed thin film battery is comprised of a polymer-lithium ion cell material with barrier-layer packaging and mechanical reinforcing layers. A semi-solid/ solid electrolyte and a mesoporous polymer separator are sandwiched in between of anode and cathode. A composite film with a carbon nanotube (CNT) network serves as the anode and a mesoporous transitional metal oxide LixCoO2 as the cathode, where porous metal sheets serve as the current collector. The CNT network fabrics have high in-plane tensile strength. LiCoO2 is used as the cathode, because the Co atoms do not migrate to Li layers, so that cathode does not generate flammable gases during charging that create safety problems. Merit of this study is using the porous metal sheet, which is flexible, lightweight, low electric resistance, high strength and strong stability in alkaline solution. This paper presented development of electrolyte for laminated polymer lithium rechargeable battery. Two-type electrolytes, semi-solid and solid, were attempted; high ionic conductivity of Li ion electrolytes was achieved.

Xu, Chunye; Ma, Chao; Taya, Minoru

2008-05-01

110

Analysis of recharge-induced geochemical change in a contaminated aquifer.  

PubMed

Recharge events that deliver electron acceptors such as O2, NO3, SO4, and Fe3+ to anaerobic, contaminated aquifers are likely important for natural attenuation processes. However, the specific influence of recharge on (bio)geochemical processes in ground water systems is not well understood. The impact of a moderate-sized recharge event on ground water chemistry was evaluated at a shallow, sandy aquifer contaminated with waste fuels and chlorinated solvents. Multivariate statistical analyses coupled with three-dimensional visualization were used to analyze ground water chemistry data (including redox indicators, major ions, and physical parameters) to reveal associations between chemical parameters and to infer processes within the ground water plume. Factor analysis indicated that dominant chemical associations and their interpreted processes (anaerobic and aerobic microbial processes, mineral precipitation/dissolution, and temperature effects) did not change significantly after the spring recharge event of 2000. However, the relative importance of each of these processes within the plume changed. After the recharge event, the overall importance of aerobic processes increased from the fourth to the second most important factor, representing the variability within the data set. The anaerobic signatures became more complex, suggesting that zones with multiple terminal electron-accepting processes (TEAPs) likely occur in the same water mass. Three-dimensional visualization of well clusters showed that water samples with similar chemical associations occurred in distinct water masses within the aquifer. Water mass distinctions were not based on dominant TEAPs, suggesting that the recharge effects on TEAPs occurred primarily at the interface between infiltrating recharge water and the aquifer. PMID:16029178

McGuire, Jennifer T; Long, David T; Hyndman, David W

111

REVISED NORTH CAROLINA GROUNDWATER RECHARGE RATES 1998  

EPA Science Inventory

Revised North Carolina Groundwater Recharge Rates, from Heath, R.C., 1994, unpublished map: North Carolina State University, as modified by the NC Department of Environment and Natural Resources (DENR) Division of Water Quality (DWQ) Groundwater Section, (polygons)...

112

Organic Pollutants in Ground-Recharged Water.  

National Technical Information Service (NTIS)

The objective of this project was to determine the identities of the haloforms (THMs) in ground recharged water as well as the concentrations and identities of the haloform precursors (THMPs). A second objective was the determination of these compounds in...

C. Steelink H. Bohn M. A. Mikita K. Thorn J. Hobson

1981-01-01

113

Rechargeable thin-film lithium batteries.  

National Technical Information Service (NTIS)

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 fabri...

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

1993-01-01

114

Method of Recharging Fire Extinguisher Bottles.  

National Technical Information Service (NTIS)

This invention relates to a method of recharging fire extinguisher bottles wherein special transfer cylindrs are used to store and discharge predetermined quantities of liquid fire suppressant and pressurizing gas to the bottle. The process is carried out...

A. J. Monte

1980-01-01

115

Rechargeable manganese oxide batteries. (Genopladelige manganoxid batterier).  

National Technical Information Service (NTIS)

Former work on lithium and sodium batteries proved the feasibility of making solid state cells with high energy density and reversibility. The utility of manganese oxides as cathode material in rechargeable alkali metal solid state intercalation batteries...

B. Zachau-Christensen K. West S. Skaarup

1992-01-01

116

Methods for Fabricating Lithium Rechargeable Batteries.  

National Technical Information Service (NTIS)

There are provided novel methods of fabricating batteries, particularly rechargeable lithium ion batteries comprising a microporous polymeric gel layer on one or more electrodes of the batteries. The methods include laminating a gellable polymer film to a...

B. Oh K. Amine

2005-01-01

117

Recharging the Ogallala Formation Using Shallow Holes.  

National Technical Information Service (NTIS)

Natural groundwater recharge cannot sustain the Southern High Plains portion of the Ogallala Formation. Nearly all the water used in this region is derived from the Ogallala Formation. The southern part of the Ogallala is hydrologically isolated from all ...

M. J. Dvoracek S. H. Peterson

1970-01-01

118

Stability and error analysis of the polarization estimation inverse problem for microbial fuel cells  

NASA Astrophysics Data System (ADS)

Determining parameters which describe the performance of a microbial fuel cell requires the solution of an inverse problem. Two formulations have been presented in the literature: a convolutional approach or a direct quadrature approach. A complete study and analysis of the direct quadrature method, which leads to two systems for the unknown signal given measured complex data, known as the distribution function of relaxation times, is presented. A theoretical analysis justifies the minimal range of integration that is appropriate for the quadrature and suggests that the systems should be combined giving an overdetermined system that is not well posed but not as ill-posed as either system considered separately. All measures of ill-posedness support using the combined data when the level of error in both components of the complex measurements is equivalent. Tikhonov regularization for the filtered singular value and truncated singular value decomposition are used to find solutions of the underlying model system. Given such solutions the application requires the determination of the model parameters that define the signal, among which are the location and peaks of the individual processes of the cell. A nonlinear data fitting approach is presented which consistently estimates these parameters. Simulations support the use of the combined systems for finding the underlying distribution function of relaxation times and the subsequent nonlinear data fitting to these curves. The approach is also illustrated for measured practical data, demonstrating that without the theoretical analysis incorrect conclusions on the underlying physical system would arise. This work justifies the use of Tikhonov regularization combined with nonlinear data fitting for finding reliable solutions for the specific model, when the signal is comprised of a mixture of signals from a small number of processes.

Renaut, R. A.; Baker, R.; Horst, M.; Johnson, C.; Nasir, D.

2013-04-01

119

Issues and challenges facing rechargeable lithium batteries  

Microsoft Academic Search

Technological improvements in rechargeable solid-state batteries are being driven by an ever-increasing demand for portable electronic devices. Lithium-ion batteries are the systems of choice, offering high energy density, flexible and lightweight design, and longer lifespan than comparable battery technologies. We present a brief historical review of the development of lithium-based rechargeable batteries, highlight ongoing research strategies, and discuss the challenges

J.-M. Tarascon; M. Armand

2001-01-01

120

Conductivity of electrolytes for rechargeable lithium batteries  

NASA Astrophysics Data System (ADS)

The conductivity of 150 nonaqueous electrolytes for rechargeable Li batteries between -60 and 80 C is reported. A wide range of solvents including esters, ethers, aromatics, chlorinated solvents, etc., and mixtures thereof, were studied. Results for five electrolyte salts which have some promise for rechargeable Li cells are presented. Several of the trends in the data are discussed, and the importance of solvent viscosity in determining electrolyte conductivity is shown.

Dudley, J. T.; Wilkinson, D. P.; Thomas, G.; Levae, R.; Woo, S.

1991-06-01

121

System for charging a rechargeable battery  

Microsoft Academic Search

This patent describes, for use in an energy-using device adapted to operate from an external source of A-C power and from either rechargeable type or non-rechargeable type batteries of the same standard size and configuration, a charging system comprising in combination: a housing for the energy-using device. The energy-using device is operable in a first mode when connected to the

Scholefield

1986-01-01

122

Proposed artificial recharge studies in northern Qatar  

USGS Publications Warehouse

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)

Kimrey, J. O.

1985-01-01

123

Application of the simplified P{sub N} approximation to mixed-oxide fuel problems  

Microsoft Academic Search

The disposition of weapons- and reactor-grade plutonium using light water reactors has received increased attention in recent years. The thermal absorption and fission cross sections in mixed-oxide (MOX) fuel assemblies are much higher than in UOâ fuel assemblies, yielding a much lower thermal flux but a higher power production in the MOX assemblies. The stronger absorption in MOX assemblies and

P. S. Brantley; D. I. Tomasevic; E. W. Larsen

1998-01-01

124

Some Problems of Operation Behaviour of Hexagonal Boxes for Fuel Elements of Fast Power Reactors.  

National Technical Information Service (NTIS)

The present work shows a method to determine the operational behaviour of hexagonal fuel cans for fast reactors by using tensions caused by the coolant pressure, and tensions due to a possible interaction of the fuel rod bundle and the can with axial symm...

A. A. Proshkin L. M. Zabud'ko

1978-01-01

125

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

Microsoft Academic Search

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

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

2010-01-01

126

Fluidized bed combustion of alternative solid fuels; status, successes and problems of the technology  

Microsoft Academic Search

Fluidized bed combustion can be used for energy production or incineration for almost any material containing carbon, hydrogen and sulphur in a combustible form, whether it be in the form of a solid, liquid, slurry or gas. The technology's fuel flexibility arises from the fact that the fuel is present in the combustor at a low level and is burnt

E. J Anthony

1995-01-01

127

Fuel-Powered Artificial Muscles  

NASA Astrophysics Data System (ADS)

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.

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

128

Battery charging system including means for distinguishing between rechargeable and non-rechargeable batteries  

Microsoft Academic Search

A battery charging system adapted to distinguish a rechargeable battery type from a non-rechargeable battery type is described, both types being of substantially similar size and having first and second external load terminals for delivering electrical energy. The system consists of: a battery charging circuit having a first non-charging mode and a second charging mode, the circuit having first and

J. S. Hodgman; F. H. Mullersman

1986-01-01

129

The flow-refueling location problem for alternative-fuel vehicles  

Microsoft Academic Search

Beginning with Hodgson (Geogr.Anal.22(1990) 270), several researchers have been developing a new kind of location-allocation model for “flow capturing.” Instead of locating central facilities to serve demand at fixed points in space, their models aim to serve demand consisting of origin-destination flows along their shortest paths. This paper extends flow-capturing models to optimal location of refueling facilities for alternative-fuel (alt-fuel)

Michael Kuby; Seow Lim

2005-01-01

130

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

NASA Astrophysics Data System (ADS)

Quantification of the timing and magnitude of point-scale groundwater recharge is challenging, but possible at specific sites given sufficient high spatial and temporal resolution field observations, and a suitable physically based model. Such models are generally too computationally intensive and have too many unknown parameters to be practically applicable within distributed, larger-scale hydrological or groundwater models. This motivates the need for simpler recharge models, which are widely used within groundwater models. However, it is important that these models are able to capture adequately the unsaturated zone flow processes. We perform an inter-comparison of recharge simulated by a detailed physically based model and a simple recharge model, with both models applied to a field site in the fractured porous Chalk in the UK. Flow processes are simulated convincingly using a dual permeability, equivalent continuum, vertically heterogeneous, Richards' equation model, applied to a 2-D hillslope transect. A simple conventional recharge model was then 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 process representations in the simple model. Specifically, 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.

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

2013-06-01

131

A study of rechargeable zinc electrodes for alkaline cells requiring anodic limitation  

Microsoft Academic Search

Problems associated with the cyclic operation of zinc electrodes in rechargeable alkaline cells for which anodic limitation is required are investigated. Experiments were conducted to determine the influence of electrolyte additives and cell construction on the capacity loss of limited zinc electrodes during cycling; current-voltage diagrams for zinc electrodes within the potential range of passivation and of hydrogen evolution were

L. Binder; W. Odar; K. Kordesch

1981-01-01

132

Modeling Recharge - can it be Done?  

NASA Astrophysics Data System (ADS)

In sub-humid areas where rainfall is relatively low and sporadic, recharge (defined as water movement beyond the active root zone) is the small difference between the much larger numbers rainfall and evapotranspiration. It is very difficult to measure and often modeling is resorted to instead. But is modeling this small number any less difficult than measurement? In Australia there is considerable debate over the magnitude of recharge under different agricultural systems because of its contribution to rising saline groundwater levels following the clearing of native vegetation in the last 100 years. Hence the adequacy of measured and modeled estimates of recharge is under close scrutiny. Results will be presented for the water balance of an intensively monitored 8 year sequence of crops and pastures. Measurements included meteorological inputs, evapotranspiration measured with a pair of weighing lysimeters, and soil water content was measured with TDR and neutron moisture meter. Recharge was estimated from the percolate removed from the lysimeters as well as, when conditions were suitable, from soil water measurements and combined soil water and evapotranspiration measurements. This data was simulated using a comprehensive soil-plant-atmosphere model (APSIM). Comparison with field measurements shows that the recharge can be simulated with an accuracy similar to that with which it can be measured. However, is either sufficiently accurate for the applications for which they are required?

Verburg, K.; Bond, W. J.; Smith, C. J.; Dunin, F. X.

2001-12-01

133

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

NASA Astrophysics Data System (ADS)

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.

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

2012-10-01

134

Apparatus for successively charging rechargeable batteries  

SciTech Connect

A charging apparatus charges a plurality of rechargeable batteries individually and in succession. Each of the plurality of rechargeable batteries is coupled to one corresponding charging branch. The charging apparatus comprises a charging completion detecting circuit for detecting a charging completion of a rechargeable battery now in a charging operation, a high voltage detecting circuit for detecting an abnormal voltage of a charging branch now in a charging operation, wherein single pulse is generated responsive to the outputs of the charging completion detecting circuit and the abnormal voltage detecting circuit. A charging branch being connected to the charging voltage source is selectively and automatically switched responsive to the above described single pulse. Furthermore, the charging completion detecting circuit and the abnormal voltage detecting circuit are reset to an initial state responsive to the above described single pulse.

Matsuura, K.; Oyamada, K.

1983-06-07

135

Impacts of vegetation change on groundwater recharge  

NASA Astrophysics Data System (ADS)

Vegetation change is the accepted cause of increasing river salt concentrations and the salinisation of millions of hectares of farm land in Australia. Replacement of perennial native vegetation by annual crops and pastures following European settlement has altered the water balance causing increased groundwater recharge and mobilising the naturally saline groundwater. The Redesigning Agriculture for Australian Landscapes Program, of which the work described here is a part, was established to develop agricultural practices that are more attuned to the delicate water balance described above. Results of field measurements will be presented that contrast the water balance characteristics of native vegetation with those of conventional agricultural plants, and indicate the functional characteristics required of new agricultural practices to reduce recharge. New agricultural practices may comprise different management of current crops and pastures, or may involve introducing totally new species. In either case, long-term testing is required to examine their impact on recharge over a long enough climate record to encompass the natural variability of rainfall that is characteristic of most Australian farming regions. Field experimentation therefore needs to be complemented and extended by computer simulation. This requires a modelling approach that is more robust than conventional crop modelling because (a) it needs to be sensitive enough to predict small changes in the residual recharge term, (b) it needs to be able to simulate a variety of vegetation in different sequences, (c) it needs to be able to simulate continuously for several decades of input data, and (d) it therefore needs to be able to simulate the period between crops, which often has a critical impact on recharge. The APSIM simulation framework will be used to illustrate these issues and to explore the effect of different vegetation combinations on recharge.

Bond, W. J.; Verburg, K.; Smith, C. J.

2003-12-01

136

Computer Program for Predicting Recharge with a Master Recession Curve.  

National Technical Information Service (NTIS)

Water-table fluctuations occur in unconfined aquifers owing to ground-water recharge following precipitation and infiltration, and ground-water discharge to streams between storm events. Ground-water recharge can be estimated from well hydrograph data usi...

C. S. Heppner J. R. Nimmo

2005-01-01

137

30 CFR 56.4203 - Extinguisher recharging or replacement.  

Code of Federal Regulations, 2013 CFR

...STANDARDS-SURFACE METAL AND NONMETAL MINES Fire Prevention and Control Firefighting Equipment § 56.4203 Extinguisher recharging or replacement. Fire extinguishers shall be recharged or replaced with a...

2013-07-01

138

30 CFR 57.4203 - Extinguisher recharging or replacement.  

Code of Federal Regulations, 2013 CFR

...STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Firefighting Equipment § 57.4203 Extinguisher recharging or replacement. Fire extinguishers shall be recharged or replaced with a...

2013-07-01

139

Quantifying Mountain Front Recharge Using Isotopic Tracers  

NASA Astrophysics Data System (ADS)

To improve our conceptual and quantitative understanding of mountain-front/mountain-block recharge (MFR) associated with the Huachuca Mountains of the Upper San Pedro River Basin in Arizona, we employed a suite of geochemical measurements including isotopic tracers and noble gases. MFR is frequently the dominant source of recharge to alluvial basins in the semiarid Basin and Range province. It consists of mountain runoff that infiltrates at the mountain front (mountain-front recharge), and percolation through the mountain bedrock that reaches the basin via the movement of deep groundwater (mountain-block recharge). The rate of MFR can be estimated from a water balance, a Darcy's law analysis, or inverse modeling of groundwater processes. Despite the large volume of research on water resources in the basin and the critical importance of MFR to the water budget, the best estimates of MFR obtained using these methods may have errors as large as 100%. We find that geochemical tracers address mechanistic questions regarding recharge seasonality, location, and rates as well as addressing groundwater flowpaths and residence times. The gradient of stable isotopes of hydrogen and oxygen in groundwater with elevation mirrors that of regional precipitation, providing a constraint on the location and seasonality of recharge. Stable isotopic signatures indicate that MFR is dominated by winter precipitation but has 1/3 or more contribution from monsoon precipitation. Detectable tritium and 14C values greater than 100 pMC for springs, shallow groundwater in mountain canyons, and from wells along the mountain front indicate decade-scale residence times. Away from the mountain front 14C values rapidly decrease, reaching 12.3±0.2 pMC near the river. This suggests total basin residence times greater than 10,000 years, consistent with past measurements. Ongoing analysis of noble gas concentrations will provide an indication of recharge conditions. The solubility of noble gases in water depends on temperature and pressure; thus, noble gas concentrations provide a means to distinguish water samples recharged at different elevations.

Wahi, A. K.; Ekwurzel, B.; Hogan, J. F.; Eastoe, C. J.; Baillie, M. N.

2005-05-01

140

Global-scale modeling of groundwater recharge  

NASA Astrophysics Data System (ADS)

Long-term average groundwater recharge, which is equivalent to renewable groundwater resources, is the major limiting factor for the sustainable use of groundwater. Compared to surface water resources, groundwater resources are more protected from pollution, and their use is less restricted by seasonal and inter-annual flow variations. To support water management in a globalized world, it is necessary to estimate groundwater recharge at the global scale. Here, we present a best estimate of global-scale long-term average diffuse groundwater recharge (i.e. renewable groundwater resources) that has been calculated by the most recent version of the WaterGAP Global Hydrology Model WGHM (spatial resolution of 0.5° by 0.5°, daily time steps). The estimate was obtained using two state-of-the art global data sets of gridded observed precipitation that we corrected for measurement errors, which also allowed to quantify the uncertainty due to these equally uncertain data sets. The standard WGHM groundwater recharge algorithm was modified for semi-arid and arid regions, based on independent estimates of diffuse groundwater recharge, which lead to an unbiased estimation of groundwater recharge in these regions. WGHM was tuned against observed long-term average river discharge at 1235 gauging stations by adjusting, individually for each basin, the partitioning of precipitation into evapotranspiration and total runoff. We estimate that global groundwater recharge was 12 666 km3/yr for the climate normal 1961-1990, i.e. 32% of total renewable water resources. In semi-arid and arid regions, mountainous regions, permafrost regions and in the Asian Monsoon region, groundwater recharge accounts for a lower fraction of total runoff, which makes these regions particularly vulnerable to seasonal and inter-annual precipitation variability and water pollution. Average per-capita renewable groundwater resources of countries vary between 8 m3/(capita yr) for Egypt to more than 1 million m3/(capita yr) for the Falkland Islands, the global average in the year 2000 being 2091 m3/(capita yr). Regarding the uncertainty of estimated groundwater resources due to the two precipitation data sets, deviation from the mean is less than 1% for 50 out of the 165 countries considered, between 1 and 5% for 62, between 5 and 20% for 43 and between 20 and 80% for 10 countries. Deviations at the grid scale can be much larger, ranging between 0 and 186 mm/yr.

Döll, P.; Fiedler, K.

2007-11-01

141

Global-scale modeling of groundwater recharge  

NASA Astrophysics Data System (ADS)

Long-term average groundwater recharge, which is equivalent to renewable groundwater resources, is the major limiting factor for the sustainable use of groundwater. Compared to surface water resources, groundwater resources are more protected from pollution, and their use is less restricted by seasonal and inter-annual flow variations. To support water management in a globalized world, it is necessary to estimate groundwater recharge at the global scale. Here, we present a best estimate of global-scale long-term average diffuse groundwater recharge (i.e. renewable groundwater resources) that has been calculated by the most recent version of the WaterGAP Global Hydrology Model WGHM (spatial resolution of 0.5° by 0.5°, daily time steps). The estimate was obtained using two state-of-the-art global data sets of gridded observed precipitation that we corrected for measurement errors, which also allowed to quantify the uncertainty due to these equally uncertain data sets. The standard WGHM groundwater recharge algorithm was modified for semi-arid and arid regions, based on independent estimates of diffuse groundwater recharge, which lead to an unbiased estimation of groundwater recharge in these regions. WGHM was tuned against observed long-term average river discharge at 1235 gauging stations by adjusting, individually for each basin, the partitioning of precipitation into evapotranspiration and total runoff. We estimate that global groundwater recharge was 12 666 km3/yr for the climate normal 1961-1990, i.e. 32% of total renewable water resources. In semi-arid and arid regions, mountainous regions, permafrost regions and in the Asian Monsoon region, groundwater recharge accounts for a lower fraction of total runoff, which makes these regions particularly vulnerable to seasonal and inter-annual precipitation variability and water pollution. Average per-capita renewable groundwater resources of countries vary between 8 m3/(capita yr) for Egypt to more than 1 million m3/(capita yr) for the Falkland Islands, the global average in the year 2000 being 2091 m3/(capita yr). Regarding the uncertainty of estimated groundwater resources due to the two precipitation data sets, deviation from the mean is 1.1% for the global value, and less than 1% for 50 out of the 165 countries considered, between 1 and 5% for 62, between 5 and 20% for 43 and between 20 and 80% for 10 countries. Deviations at the grid scale can be much larger, ranging between 0 and 186 mm/yr.

Döll, P.; Fiedler, K.

2008-05-01

142

Lithium-manganese oxide rechargeable battery  

SciTech Connect

A new type of rechargeable battery in which lithium ions shuttle between a lithium-manganese oxide electrode and a carbon electrode was unveiled recently by chemists from Bell Communications Research (Bellcore), Red Bank, N.J. The new battery--still experimental--is safer, longer lasting, and potentially cheaper to manufacture than other lithium-ion batteries. In addition, it provides three times the energy of nickel-cadmium cells, the most popular type of rechargeable battery. Bellcore scientists believe the new battery could replace nickel-cadmium and small lead-acid batteries in many applications.

Dagani, R.

1993-01-04

143

Long-term lining performance – Civil engineering problem of potential retrieval of buried spent nuclear fuel  

Microsoft Academic Search

The current solution for the spent fuel, high-level and long-lived radioactive waste is to store them at surface facilities from which they will be subsequently moved to a deep repository. No such repositories are in operation currently but several such facilities are close to the construction phase. A deep repository can be situated in several types of geological conditions including

Radek Vaší?ek; Ji?í Svoboda

2011-01-01

144

Changing to Domestic Fuels or Municipal Waste in Coal Boilers. Technical and Environmental Problems.  

National Technical Information Service (NTIS)

This study examines from technical and environmental point of view, the impact of changing to domestic fuels (Swedish) or municipal waste in coal boilers, or preparing boilers for conversion or cofiring at the time of construction. The study is on boilers...

S. Malin L. Aastroem

1983-01-01

145

Rechargeable battery and electrical circuit for charging thereof  

Microsoft Academic Search

This patent describes a nickel-cadmium rechargeable cell for use in an energy-using device having at least one charging terminal contact for recharging the cell. The energy-using device adapted to alternately receive either a standard cylindrical AA, AAA, C or D size non-rechargeable cell has a pair of power terminal contacts spaced apart by a standard distance. The rechargeable cell comprises:

Toops

1987-01-01

146

Control circuit for a solar-powered rechargeable power source and load  

Microsoft Academic Search

A solar rechargeable apparatus is described comprising: a rechargeable power source; a solar panel connected to the rechargeable power source for supplying a charging current to the rechargeable power source; a device connected between the rechargeable power source and the solar panel to prevent discharge of current from the rechargeable power source to the solar panel; a load; and a

R. W. Janda; J. L. Douglas; E. F. Jr. Condon

1993-01-01

147

Recent advances in rechargeable battery materials: a chemist's perspective.  

PubMed

The constant increase in global energy demand, together with the awareness of the finite supply of fossil fuels, has brought about an imperious need to take advantage of renewable energy sources. At the same time, concern over CO(2) emissions and future rises in the cost of gasoline has boosted technological efforts to make hybrid and electric vehicles available to the general public. Energy storage is a vital issue to be addressed within this scenario, and batteries are certainly a key player. In this tutorial review, the most recent and significant scientific advances in the field of rechargeable batteries, whose performance is dependent on their underlying chemistry, are covered. In view of its utmost current significance and future prospects, special emphasis is given to progress in lithium-based technologies. PMID:19690737

Palacín, M Rosa

2009-06-23

148

Solid polymer electrolytes for rechargeable batteries. Final report  

SciTech Connect

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.

Narang, S.C.; Ventura, S.C. [SRI International, Menlo Park, CA (United States). Chemistry Lab.

1992-02-01

149

Fundamental Concepts of Recharge in the Desert Southwest  

Microsoft Academic Search

Recharge in arid basins does not occur in all years or at all locations. To address the temporal and spatial variability of recharge, one must (1) distinguish between recharge and net infiltration, (2) understand travel time in the unsaturated zone, and (3) comprehend the local- and basin-scale deterministic processes and surficial properties that control net infiltration. Net infiltration is the

A. L. Flint; L. E. Flint; J. B. Blainey; J. A. Hevesi

2001-01-01

150

Natural vs. artificial groundwater recharge, quantification through inverse modeling  

NASA Astrophysics Data System (ADS)

Estimating the change in groundwater recharge from an introduced artificial recharge system is important in order to evaluate future water availability. This paper presents an inverse modeling approach to quantify the recharge contribution from both an ephemeral river channel and an introduced artificial recharge system based on floodwater spreading in arid Iran. The study used the MODFLOW-2000 to estimate recharge for both steady- and unsteady-state conditions. The model was calibrated and verified based on the observed hydraulic head in observation wells and model precision, uncertainty, and model sensitivity were analyzed in all modeling steps. The results showed that in a normal year without extreme events, the floodwater spreading system is the main contributor to recharge with 80% and the ephemeral river channel with 20% of total recharge in the studied area. Uncertainty analysis revealed that the river channel recharge estimation represents relatively more uncertainty in comparison to the artificial recharge zones. The model is also less sensitive to the river channel. The results show that by expanding the artificial recharge system, the recharge volume can be increased even for small flood events, while the recharge through the river channel increases only for major flood events.

Hashemi, H.; Berndtsson, R.; Kompani-Zare, M.; Persson, M.

2013-02-01

151

Natural vs. artificial groundwater recharge, quantification through inverse modeling  

NASA Astrophysics Data System (ADS)

Estimating the change in groundwater recharge from an introduced artificial recharge system is important in order to evaluate future water availability. This paper presents an inverse modeling approach to quantify the recharge contribution from both an ephemeral river channel and an introduced artificial recharge system based on floodwater spreading in arid Iran. The study used the MODFLOW-2000 to estimate recharge for both steady and unsteady-state conditions. The model was calibrated and verified based on the observed hydraulic head in observation wells and model precision, uncertainty, and model sensitivity were analyzed in all modeling steps. The results showed that in a normal year without extreme events the floodwater spreading system is the main contributor to recharge with 80% and the ephemeral river channel with 20% of total recharge in the studied area. Uncertainty analysis revealed that the river channel recharge estimation represents relatively more uncertainty in comparison to the artificial recharge zones. The model is also less sensitive to the river channel. The results show that by expanding the artificial recharge system the recharge volume can be increased even for small flood events while the recharge through the river channel increases only for major flood events.

Hashemi, H.; Berndtsson, R.; Kompani-Zare, M.; Persson, M.

2012-08-01

152

Estimating recharge rates with analytic element models and parameter estimation  

USGS Publications Warehouse

Quantifying the spatial and temporal distribution of recharge is usually a prerequisite for effective ground water flow modeling. In this study, an analytic element (AE) code (GFLOW) was used with a nonlinear parameter estimation code (UCODE) to quantify the spatial and temporal distribution of recharge using measured base flows as calibration targets. The ease and flexibility of AE model construction and evaluation make this approach well suited for recharge estimation. An AE flow model of an undeveloped watershed in northern Wisconsin was optimized to match median annual base flows at four stream gages for 1996 to 2000 to demonstrate the approach. Initial optimizations that assumed a constant distributed recharge rate provided good matches (within 5%) to most of the annual base flow estimates, but discrepancies of >12% at certain gages suggested that a single value of recharge for the entire watershed is inappropriate. Subsequent optimizations that allowed for spatially distributed recharge zones based on the distribution of vegetation types improved the fit and confirmed that vegetation can influence spatial recharge variability in this watershed. Temporally, the annual recharge values varied >2.5-fold between 1996 and 2000 during which there was an observed 1.7-fold difference in annual precipitation, underscoring the influence of nonclimatic factors on interannual recharge variability for regional flow modeling. The final recharge values compared favorably with more labor-intensive field measurements of recharge and results from studies, supporting the utility of using linked AE-parameter estimation codes for recharge estimation. Copyright ?? 2005 The Author(s).

Dripps, W. R.; Hunt, R. J.; Anderson, M. P.

2006-01-01

153

Circuit Model of Battery Recharging by Volume Conduction  

Microsoft Academic Search

Many current implantable devices require large capacity batteries implanted in the body. In this paper we present a new approach of transcutaneous battery recharging by volume conduction and its circuit model. We also analyze the current transmitting efficiency and rechargeable prerequisite of transcutaneous battery recharging by applying this circuit model. The experiments prove the legitimacy of the circuit model.

Zhide Tang; R. J. Sclabassi; Caixin Sun; Jun Zhao; S. A. Hackworth; Mingui Sun

2006-01-01

154

Analysis of the infrastructure for recharging electric vehicles  

Microsoft Academic Search

An analysis of the infrastructure ofr recharging electric vehicles (EV), equivalent to the refueling infrastructure for internal combustion engines (ICE), shows that many of the infrastructure elements required to recharge a large number of EV's in the U.S. are already in place. The U.S. utility industry has sufficient capacity to support at least 13 million EV's if they are recharged

R. Kaiser; C. Graver

1980-01-01

155

Global synthesis of groundwater recharge in semiarid and arid regions  

Microsoft Academic Search

Global synthesis of the findings from ¾140 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

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

2006-01-01

156

Global synthesis of groundwater recharge in semiarid and arid regions  

Microsoft Academic Search

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

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

2006-01-01

157

Potential for Recharge in Agricultural Soils of the Mississippi Delta  

Microsoft Academic Search

Ground water models predict that 5 percent or less of precipitation in the Mississippi Delta region recharges the heavily-used alluvial aquifer; however the presence of agricultural chemicals in ground water suggests more substantial recharge. In a preliminary assessment of the potential for aerial recharge through the agricultural soils of the Bogue Phalia basin in the Mississippi Delta, we applied a

K. S. Perkins; J. R. Nimmo; R. H. Coupe; C. E. Rose; M. A. Manning

2007-01-01

158

Past and future of the petroleum problem; The increasing need to develop alternative transportation fuels  

SciTech Connect

This paper reports on an examination of the interactions of petroleum supply and demand patterns which suggests that the depletion of U.S. oil reserves and the increasing importance of oil consumption in U.S. transportation are causes for greater attention to the development of alternative (nonpetroleum-based) transportation fuels. Absent such development, the historical lessons presented in this paper suggest that another period of rising oil prices, erratic oil market behavior, and subsequent economic difficulty is probable within the next two decades. Methanol is argued to be the most likely and most desirable substitute transportation fuel because it can be produced more economically and used more efficiently than gasoline when derived from the rapidly expanding worldwide supplies of natural gas.

Santini, D.J. (Energy and Environmental Systems Div., Center for Transportation Research, Argonne National Lab., Argonne, IL (US))

1988-01-01

159

The application of HTR coated fuel particle performance models to various problems in materials' science  

NASA Astrophysics Data System (ADS)

A number of stress models of varying complexity are developed in a high temperature reactor to predict the irradiation performance of coated fuel particles for the HTR system. These are applied to account for experimental observations in the following three fields of materials' science: (1) the increase in failure fraction with time as a bath of irradiated coated particles is annealed at 1600 C, by way of the simulation of a reactor accident, (2) the coefficient of thermal expansion (cte) of copper, loaded with a high concentration of very small krypton gas bubbles as a means of safely immobilizing Kr(85) during the reprocessing of fuel and (3) the cte of polymer composites containing a random dispersal of second phase near spherical particles. The silicon carbide in an irradiated coated particle exhibits selective corrosion at 1600 C. Solids loaded with gas bubbles exhibit cte values which are greater and less than that of the matrix material. The mathematical basis of a cylindrical fuel pin performance model is developed.

Martin, D. G.

1983-10-01

160

REUSE OF MUNICIPAL WASTEWATER FOR GROUNDWATER RECHARGE  

EPA Science Inventory

A survey of groundwater recharge operations with municipal wastewater effluent was conducted. It was found that this activity is being practiced at 10 sites in the U.S. with a total capacity of 77 MGD. The most successful employ percolation with alternate flooding and drying cycl...

161

Anode for rechargeable ambient temperature lithium cells  

Microsoft Academic Search

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.

Chen-Kuo Huang; Subbarao Surampudi; Alan I. Attia; Gerald Halpert

1994-01-01

162

Anode for rechargeable ambient temperature lithium cells  

Microsoft Academic Search

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.

Chen-Kuo Huang; Subbarao Surampudi; Alan I. Attia; Gerald Halpert

1992-01-01

163

High temperature rechargeable molten salt cell  

Microsoft Academic Search

This patent describes a high temperature rechargeable molten salt cell. It comprises: a member of the group consisting of lithium, lithium aluminum alloy, lithium silicon alloy, sodium, potassium, calcium, magnesium, an alkali metal, a group II A element, a group II A alloy and composite mixtures thereof, as the anode, a chemical compound of the composition XYSâ wherein X is

E. J. Plichta; W. K. Behl

1991-01-01

164

Application potential of rechargeable lithium batteries  

SciTech Connect

Rechargeable lithium cells with Cr /SUB 0.5/ V/sub 0/ /sub 5/S/sub 2/ and MoO/sub 3/ cathodes were investigated in the temperature range of -30/sup 0/C to +25/sup 0/C. The electrolyte was 1.5M LiAsF/sub 6/ in 2-methyl tetrahydrofuran with tetrahydrofuran (50:50 V percent). Current densities and capacities as a function of temperature, cathode utilization efficiencies versus cycle life, and shelf lives were determined. The state of charge could be related to open circuit voltages after partial discharge. The potential of the system for communication applications is discussed. Recent advances in rechargeable lithium batteries were mainly due to the discovery of stable, cyclic ether electrolyte solvents (1) and to the use of rechargeable cathode materials (2). The practical usefulness of rechargeable lithium cells with Cr /SUB 0.5/ V /SUB 0.5/ S/sub 2/ and MoO/sub 3/ cathodes was investigated in the temperature range of -30/sup 0/C to +25/sup 0/C. The electrolyte was mainly 1.5M LiAsF/sub 6/ in 2-methyl tetrahydrofuran with tetrahydrofuran (50:50 V percent). The two cathode materials were chosen because Cr /SUB 0.5/ V /SUB 0.5/ S/sub 2/ resembles TiS/sub 2/ in capacity and cycling behavior and MoO/sub 3/ is a low cost cathode material of interest.

Hunger, H.F.; Bramhall, P.J.

1983-10-01

165

Battery recharging circuit with indicator means  

Microsoft Academic Search

This patent describes a recharging circuit including a diode and a battery serially connected and coupled in parallel to a power source. The circuit consists of: first means connected across the power source for indicating the presence of a charging current delivered by the power source; second means connected between the power source and the junction of the diode with

Keiper

1986-01-01

166

High reliability lithium rechargeable batteries for specialties  

Microsoft Academic Search

Since their development in the late 1980s, lithium rechargeable batteries have enjoyed rapid growth and wide use as a commodity battery known for its higher energy density storage and lightweight convenience. These same attributes are emerging as a strong platform in power source development for the medical and aerospace sectors with highly customized applications and narrowly defined criteria. Accordingly, this

H. Tsukamoto

2003-01-01

167

All inorganic ambient temperature rechargeable lithium battery  

NASA Astrophysics Data System (ADS)

Having the advantages of high energy density and good charge retention, rechargeable lithium batteries have been of interest to many companies and research organizations within the last 15 years. Various lithium rechargeable systems with different positive electrodes and electrolytes have been reported in literature. Most are using electrolytes with organic solvents. Duracell Inc. has demonstrated the feasibility of using totally inorganic electrolytes based on liquid SO2 for the ambient temperature recharageable lithium battery. The system has lithium as the negative electrode and porous carbon as the positive electrode with SO2 as the depolarizer and electrolyte solvent. A four year cost-shared joint program with the Department of Energy was initiated in October 1980 to investigate the SO2-based electrolytes and to develop an ambient temperature rechargeable lithium battery for future energy storage applications. The ultimate goal of this program is to develop a battery having an energy density over 150 whkg with cycle life of 500 to 800 at 80 to 100 percent depth of discharge. During the four years, SO2 electrolytes with various inorganic salts and various positive electrodes made of porous carbon and solid active materials were evaluated. Promising systems having good rechargeability and high energy density, such as LiCuCl2 and LiLiAlCl4-SO2 carbon were identified. This report summarizes the progress achieved in the program.

Kuo, H. C.; Dey, A. N.; Schlaikjer, C.; Foster, D.; Kallianidis, M.

1987-10-01

168

Recharging Our Sense of Idealism: Concluding Thoughts  

ERIC Educational Resources Information Center

|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…

D'Andrea, Michael; Dollarhide, Colette T.

2011-01-01

169

Solid polymer electrolytes for rechargeable batteries  

Microsoft Academic Search

SRI International has synthesized novel solid polymer electrolytes for high energy density, rechargeable lithium batteries. We have systematically replaced the oxygens in polyethylene oxide (PEO) with sulfur to reduce the strong hard-acid hard-base interaction, while retaining the favorable helical conformation of the polymer backbone. The best polymer electrolyte produced so far is suitable for a medium power battery. In another

S. C. Narang; D. D. MacDonald

1990-01-01

170

Lithium-polymer electrolyte rechargeable batteries  

Microsoft Academic Search

There have been increasing efforts to develop lithium\\/polymer rechargeable batteries with high rate capability and long cycle life. Research efforts in preparing novel lithium-polymer electrolytes with enhanced conductivity have shown some progress and there is a great need for high conductivity electrolytes. Improvements made in the preparation of electrolytes with enhanced conductivity are described. Results of our research and development

H. V. Venkatasetty

2000-01-01

171

Application of metallocenes in rechargeable lithium batteries for overcharge protection  

SciTech Connect

One problem encountered in the development of rechargeable lithium batteries is the protection of individual cells from overcharging. In this paper the addition of metallocene derivatives to cell electrolytes to provide overcharge protection was investigated. Eleven ferrocene derivatives were studied in terms of their redox potentials and mass transport properties in electrochemical cells and AA-size Li/Li{sub x}MnO{sub 2} rechargeable cells employing 1M LiAsF{sub 6} in 50/50 volume percent propylene carbonate/ethylene carbonate (PC/EC) as the electrolyte. The chemical and electrochemical properties of these metallocene derivatives were also studied in terms of the chemical stability of the derivatives toward cell components and electrochemical reversibility in long-term cycling studies. It was found that adsorption of one derivative, dimethylaminomethylferrocene, on the Li{sub x}MnO{sub 2} electrode ({Delta}G{sub ads} = {minus}3.8 kcal mol{sup {minus}1} based on the Langmuir adsorption isotherm), blocked the intercalation of Li{sup +} ions in the Li{sub x}MnO{sub 2} electrode.

Golovin, M.N.; Wilkinson, D.P.; Dudley, J.T.; Holonko, D.; Woo, S. (Moli Energy Ltd., Burnaby, British Columbia V5C 4G2 (CA))

1992-01-01

172

Rechargeable LI2O2 electrode for lithium batteries.  

PubMed

Rechargeable lithium batteries represent one of the most important developments in energy storage for 100 years, with the potential to address the key problem of global warming. However, their ability to store energy is limited by the quantity of lithium that may be removed from and reinserted into the positive intercalation electrode, Li(x)CoO(2), 0.5 < x < 1 (corresponding to 140 mA.h g(-1) of charge storage). Abandoning the intercalation electrode and allowing Li to react directly with O(2) from the air at a porous electrode increases the theoretical charge storage by a remarkable 5-10 times! Here we demonstrate two essential prerequisites for the successful operation of a rechargeable Li/O(2) battery; that the Li(2)O(2) formed on discharging such an O(2) electrode is decomposed to Li and O(2) on charging (shown here by in situ mass spectrometry), with or without a catalyst, and that charge/discharge cycling is sustainable for many cycles. PMID:16433559

Ogasawara, Takeshi; Débart, Aurélie; Holzapfel, Michael; Novák, Petr; Bruce, Peter G

2006-02-01

173

Reversible (unitised) PEM fuel cell devices  

Microsoft Academic Search

Regenerative fuel cells (RFCs) are enabling for many weight-critical portable applications, since the packaged specific energy (>400 Wh\\/kg) of properly designed lightweight RFC systems is several-fold higher than that of the lightest weight rechargeable batteries. RFC systems can be rapidly refueled (like primary fuel cells), or can be electrically recharged (like secondary batteries) if a refueling infrastructure is not conveniently

Trent M. Molter; William F. Smith; Weisberg; Molter

1999-01-01

174

Layered perovskite oxide: a reversible air electrode for oxygen evolution/reduction in rechargeable metal-air batteries.  

PubMed

For the development of a rechargeable metal-air battery, which is expected to become one of the most widely used batteries in the future, slow kinetics of discharging and charging reactions at the air electrode, i.e., oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), respectively, are the most critical problems. Here we report that Ruddlesden-Popper-type layered perovskite, RP-LaSr3Fe3O10 (n = 3), functions as a reversible air electrode catalyst for both ORR and OER at an equilibrium potential of 1.23 V with almost no overpotentials. The function of RP-LaSr3Fe3O10 as an ORR catalyst was confirmed by using an alkaline fuel cell composed of Pd/LaSr3Fe3O10-2x(OH)2x·H2O/RP-LaSr3Fe3O10 as an open circuit voltage (OCV) of 1.23 V was obtained. RP-LaSr3Fe3O10 also catalyzed OER at an equilibrium potential of 1.23 V with almost no overpotentials. Reversible ORR and OER are achieved because of the easily removable oxygen present in RP-LaSr3Fe3O10. Thus, RP-LaSr3Fe3O10 minimizes efficiency losses caused by reactions during charging and discharging at the air electrode and can be considered to be the ORR/OER electrocatalyst for rechargeable metal-air batteries. PMID:23802735

Takeguchi, Tatsuya; Yamanaka, Toshiro; Takahashi, Hiroki; Watanabe, Hiroshi; Kuroki, Tomohiro; Nakanishi, Haruyuki; Orikasa, Yuki; Uchimoto, Yoshiharu; Takano, Hiroshi; Ohguri, Nobuaki; Matsuda, Motofumi; Murota, Tadatoshi; Uosaki, Kohei; Ueda, Wataru

2013-07-18

175

Quantifying macropore recharge: Examples from a semi-arid area  

USGS Publications Warehouse

The purpose of this paper is to illustrate the significantly increased resolution of determining macropore recharge by combining physical, chemical, and isotopic methods of analysis. Techniques for quantifying macropore recharge were developed for both small-scale (1 to 10 km2) and regional-scale areas in and semi-arid areas. The Southern High Plains region of Texas and New Mexico was used as a representative field site to test these methods. Macropore recharge in small-scale areas is considered to be the difference between total recharge through floors of topographically dosed basins and interstitial recharge through the same area. On the regional scale, macropore recharge was considered to be the difference between regional average annual recharge and interstitial recharge measured in the unsaturated zone. Stable isotopic composition of ground water and precipitation was used us an independent estimate of macropore recharge on the regional scale. Results of this analysis suggest that in the Southern High Plains recharge flux through macropores is between 60 and 80 percent of the total 11 mm/y. Between 15 and 35 percent of the recharge occurs by interstitial recharge through the basin floors. Approximately 5 percent of the total recharge occurs as either interstitial or matrix recharge between the basin floors, representing approximately 95 percent of the area. The approach is applicable to other arid and semi-arid areas that focus rainfall into depressions or valleys.The purpose of this paper is to illustrate the significantly increased resolution of determining macropore recharge by combining physical, chemical, and isotopic methods of analysis. Techniques for quantifying macropore recharge were developed for both small-scale (1 to 10 km2) and regional-scale areas in arid and semi-arid areas. The Southern High Plains region of Texas and New Mexico was used as a representative field site to test these methods. Macropore recharge in small-scale areas is considered to be the difference between total recharge through floors of topographically closed basins and interstitial recharge through the same area. On the regional scale, macropore recharge was considered to be the difference between regional average annual recharge and interstitial recharge measured in the unsaturated zone. Stable isotopic composition of ground water and precipitation was used as an independent estimate of macropore recharge on the regional scale. Results of this analysis suggest that in the Southern High Plains recharge flux through macropores is between 60 and 80 percent of the total 11 mm/y. Between 15 and 35 percent of the recharge occurs by interstitial recharge through the basin floors. Approximately 5 percent of the total recharge occurs as either interstitial or matrix recharge between the basin floors, representing approximately 95 percent of the area. The approach is applicable to other arid and semi-arid areas that focus rainfall into depressions or valleys.

Wood, W. W.; Rainwater, K. A.; Thompson, D. B.

1997-01-01

176

Automatic rainfall recharge model induction by evolutionary computational intelligence  

NASA Astrophysics Data System (ADS)

Genetic programming (GP) is used to develop models of rainfall recharge from observations of rainfall recharge and rainfall, calculated potential evapotranspiration (PET) and soil profile available water (PAW) at four sites over a 4 year period in Canterbury, New Zealand. This work demonstrates that the automatic model induction method is a useful development in modeling rainfall recharge. The five best performing models evolved by genetic programming show a highly nonlinear relationship between rainfall recharge and the independent variables. These models are dominated by a positive correlation with rainfall, a negative correlation with the square of PET, and a negative correlation with PAW. The best performing GP models are more reliable than a soil water balance model at predicting rainfall recharge when rainfall recharge is observed in the late spring, summer, and early autumn periods. The "best" GP model provides estimates of cumulative sums of rainfall recharge that are closer than a soil water balance model to observations at all four sites.

Hong, Yoon-Seok Timothy; White, Paul A.; Scott, David M.

2005-08-01

177

Automatic rainfall recharge model induction by evolutionary computational intelligence  

NASA Astrophysics Data System (ADS)

Genetic programming (GP) is used to develop models of rainfall recharge from observations of rainfall recharge and rainfall, calculated potential evapotranspiration (PET) and soil profile available water (PAW) at four sites over a 4 year period in Canterbury, New Zealand. This work demonstrates that the automatic model induction method is a useful development in modeling rainfall recharge. The five best performing models evolved by genetic programming show a highly nonlinear relationship between rainfall recharge and the independent variables. These models are dominated by a positive correlation with rainfall, a negative correlation with the square of PET, and a negative correlation with PAW. The best performing GP models are more reliable than a soil water balance model at predicting rainfall recharge when rainfall recharge is observed in the late spring, summer, and early autumn periods. The ``best'' GP model provides estimates of cumulative sums of rainfall recharge that are closer than a soil water balance model to observations at all four sites.

Hong, Yoon-Seok Timothy; White, Paul A.; Scott, David M.

2005-08-01

178

Manganese oxide cathodes for rechargeable batteries  

NASA Astrophysics Data System (ADS)

Manganese oxides are considered as promising cathodes for rechargeable batteries due to their low cost and low toxicity as well as the abundant natural resources. In this dissertation, manganese oxides have been investigated as cathodes for both rechargeable lithium and alkaline batteries. Nanostructured lithium manganese oxides designed for rechargeable lithium cells have been synthesized by reducing lithium permanganate with methanol or hydrogen in various solvents followed by firing at moderate temperatures. The samples have been characterized by wet-chemical analyses, thermal methods, spectroscopic methods, and electron microscopy. It has been found that chemical residues in the oxides such as carboxylates and hydroxyl groups, which could be controlled by varying the reaction medium, reducing agents, and additives, make a significant influence on the electrochemical properties. The Li/Mn ratio in the material has also been found to be a critical factor in determining the rechargeability of the cathodes. The optimized samples exhibit a high capacity of close to 300 mAh/g with good cyclability and charge efficiency. The high capacity with a lower discharge voltage may make these nanostructured oxides particularly attractive for lithium polymer batteries. The research on the manganese oxide cathodes for alkaline batteries is focused on an analysis of the reaction products generated during the charge/discharge processes or by some designed chemical reactions mimicking the electrochemical processes. The factors influencing the formation of Mn3O4 in the two-electron redox process of delta-MnO2 have been studied with linear sweep voltammetry combined with X-ray diffraction. The presence of bismuth, the discharge rate, and the microstructure of the electrodes are found to affect the formation of Mn3O4, which is known to be electrochemically inactive. A faster voltage sweep and a more intimate mixing of the manganese oxide and carbon in the cathode are found to suppress the formation of Mn3O4. Bismuth has also been found to be beneficial in the one-electron process of gamma-MnO 2 when incorporated into the cathode. The results of a series of chemical reactions reveal that bismuth is blocking some reaction paths leading to the unwanted birnessite or Mn3O4. Barium is also found to play a similar role, but it is less effective than bismuth for the same amount of additive. Optimization of the additives has the potential to make the rechargeable alkaline cells based on manganese oxides to successfully compete with other rechargeable systems due to their low cost, environmental friendliness, and excellent safety features.

Im, Dongmin

179

Rechargeable Infection-responsive Antifungal Denture Materials  

PubMed Central

Candida-associated denture stomatitis (CADS) is a significant clinical concern. We developed rechargeable infection-responsive antifungal denture materials for potentially managing the disease. Polymethacrylic acid (PMAA) was covalently bound onto diurethane dimethacrylate denture resins in the curing step. The PMAA resins bound cationic antifungal drugs such as miconazole and chlorhexidine digluconate (CG) through ionic interactions. The anticandidal activities of the drug-containing PMAA-resin discs were sustained for a prolonged period of time (weeks and months). Drug release was much faster at acidic conditions (pH 5) than at pH 7. Drugs bound to the denture materials could be “washed out” by treatment with EDTA, and the drug-depleted resins could be recharged with the same or a different class of anticandidal drugs. These results suggest clinical potential of the newly developed antifungal denture materials in the management of CADS and other infectious conditions.

Cao, Z.; Sun, X.; Yeh, C.-K.; Sun, Y.

2010-01-01

180

Solid polymer electrolytes for rechargeable batteries  

SciTech Connect

SRI International has synthesized novel solid polymer electrolytes for high energy density, rechargeable lithium batteries. We have systematically replaced the oxygens in PEO with sulfur to reduce the strong hard-acid hard-base interaction, while retaining the favorable helical conformation of the polymer backbone. The best polymer electrolyte produced so far is suitable for a medium power battery. In another effort, we have synthesized single ion conducting polymer electrolytes based on polyethyleneimine, polyphosphazene, and polysiloxane backbones. The single ion conducting polymer electrolytes will allow greater depth of charge and discharge by preventing dc polarization. The best conductivity so far with single ion conductors is 1.0 {times} 10{sup {minus}3} Scm{sup {minus}1} at room temperature. Further optimization of electrical and mechanical properties will allow the use of these polymer electrolytes in the fabrication of rechargeable lithium batteries. 8 tabs.

Narang, S.C.; Macdonald, D.D.

1990-11-01

181

Rechargeable Infection-responsive Antifungal Denture Materials  

Microsoft Academic Search

Candida-associated denture stomatitis (CADS) is a significant clinical concern. We developed rechargeable infection-responsive antifungal denture materials for potentially managing the disease. Polymethacrylic acid (PMAA) was covalently bound onto diurethane dimethacrylate denture resins in the curing step. The PMAA resins bound cationic antifungal drugs such as miconazole and chlorhexidine digluconate (CG) through ionic interactions. The anticandidal activities of the drug-containing PMAA-resin

Z. Cao; X. Sun; C.-K. Yeh; Y. Sun

2010-01-01

182

Rechargeable Antibacterial and Antifungal Polymeric Silver Sulfadiazines  

Microsoft Academic Search

Poly(methyl methacrylate) (PMMA)-based rechargeable antibacterial and antifungal polymeric silver sulfadiazines were prepared by copolymerizing acryloyl sulfadiazine with methyl methacrylate and sequentially treating the copolymers with dilute silver nitrate aqueous solutions. The chemical structures of the samples were characterized by FT-IR, 1H-NMR, XPS, and TGA analyses. On contact, the PMMA-based polymeric silver sulfadiazines provided 100% inactivation of 108—109 CFU\\/mL of Escherichia

Zhengbing Cao; Xinbo Sun; Yuyu Sun; Hao Fong

2009-01-01

183

Rechargeable Lithium Batteries with Aqueous Electrolytes  

NASA Astrophysics Data System (ADS)

Rechargeable lithium-ion batteries that use an aqueous electrolyte have been developed. Cells with LiMn_2O_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 nickel-cadmium and lead-acid batteries on the basis of stored energy per unit of weight.

Li, Wu; Dahn, J. R.; Wainwright, D. S.

1994-05-01

184

Recharge pattern of contemporary glass ionomer restoratives  

PubMed Central

Background: As glass ionomers have the ability to reload fluoride from outside sources, the aim was to compare the recharge pattern of six glass ionomer cements after exposure to fluoride. Materials and Methods: Fuji VII, Fuji IX, Riva Pink, Riva Bleach, Ketac Fil and Fuji IX Extra were investigated. The fluoride-containing materials used were tooth paste and mouth wash (Colgate). Specimens of each material (n=15) were immersed separately in deionized water for 59 days. Then the samples of each material were divided into three groups of five each. Two groups were recharged for 2, 20 and 60 min daily during three consecutive weekly intervals and then no treatment for one week. The third group was used as control. Fluoride release measurements (?g/cm2/day) were made in every 24 h. One-way and repeated measures analysis of variance tests were used. Results: Tooth paste recharged materials showed higher level of recharge. On day 1, the difference of fluoride release from different treatment groups of different materials except for Fuji IX Extra were not significant (P>0.05). On days 7 and 14, the differences observed were significant (P<0.05) for all materials except for Fuji VII (tooth paste versus mouth wash) and Trial Fuji IX (mouth wash versus control) and on day 14 for Rvia Pink (mouth wash versus control). On days 21 and 28, the differences observed were significant for all the materials (P<0.05) except for Riva Pink (toothpaste versus mouth wash), Riva Bleach, Ketac Fil and Trial FujiI X (mouth wash versus control) on day 28. Conclusion: A time tabled schedule of application of fluoride-containing materials could help to achieve high fluoride release.

Arbabzadeh-Zavareh, Farahnaz; Gibbs, Tim; Meyers, Ian A.; Bouzari, Majid; Mortazavi, Shiva; Walsh, Laurence J.

2012-01-01

185

Application potential of rechargeable lithium batteries  

Microsoft Academic Search

Rechargeable lithium cells with Cr \\/SUB 0.5\\/ Vâ âSâ and MoOâ cathodes were investigated in the temperature range of -30°C to +25°C. The electrolyte was 1.5M LiAsFâ in 2-methyl tetrahydrofuran with tetrahydrofuran (50:50 V percent). Current densities and capacities as a function of temperature, cathode utilization efficiencies versus cycle life, and shelf lives were determined. The state of charge could

H. F. Hunger; P. J. Bramhall

1983-01-01

186

Recharge monitoring in an interplaya setting  

SciTech Connect

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.

Scanlon, B.R.; Reedy, R.C.; Liang, J. [Univ. of Texas, Austin, TX (United States). Bureau of Economic Geology

1999-03-01

187

Lithium-manganese oxide rechargeable battery  

Microsoft Academic Search

A new type of rechargeable battery in which lithium ions shuttle between a lithium-manganese oxide electrode and a carbon electrode was unveiled recently by chemists from Bell Communications Research (Bellcore), Red Bank, N.J. The new battery--still experimental--is safer, longer lasting, and potentially cheaper to manufacture than other lithium-ion batteries. In addition, it provides three times the energy of nickel-cadmium cells,

Dagani

1993-01-01

188

High specific power lithium polymer rechargeable battery  

Microsoft Academic Search

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 (3000 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 a energy density of 100 Wh\\/kg

May-Ying Chu; Lutgard De Jonghe; Steven Visco

1996-01-01

189

Solid polymer electrolytes for rechargeable batteries  

Microsoft Academic Search

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 tetraethylorthosilicate (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

Subhash C. Narang; Susanna C. Ventura

1992-01-01

190

Rechargeable batteries and battery management systems design  

Microsoft Academic Search

Estimated worldwide sales for rechargeable batteries, was around US$36 billion in 2008 and this is expected to grow towards US$51 billion by 2013. As per market reports, US demand for primary and secondary batteries will increase by 2.5% annually to 16.8 billion in 2012, while primary batteries will account for 5.8 billion with a growth rate of 3%. The insatiable

N. Kularatna

2010-01-01

191

Rechargeable lithium batteries with aqueous electrolytes.  

PubMed

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

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

1994-05-20

192

Ground water recharge from Lake Chad  

SciTech Connect

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.

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

1985-01-01

193

Probabilistic analysis of the effects of climate change on groundwater recharge  

Microsoft Academic Search

Groundwater recharge is likely to be affected by climate change. In semiarid regions where groundwater resources are often critical, annual recharge rates are typically small and most recharge occurs episodically. Such episodic recharge is uncertain and difficult to predict. This paper analyzes the impacts of different climate predictions on diffuse episodic recharge at a low-relief semiarid rain-fed agricultural area. The

Gene-Hua Crystal Ng; Dennis McLaughlin; Dara Entekhabi; Bridget R. Scanlon

2010-01-01

194

Modelling overbank flood recharge at a continental scale  

NASA Astrophysics Data System (ADS)

Accounting for groundwater recharge from overbank flooding is required to reduce uncertainty and error in river loss terms and groundwater sustainable yield calculations. However, continental and global scale models of surface water-groundwater interactions rarely include an explicit process to account for overbank flood recharge (OFR). This paper upscales previously derived analytical equations to a continental scale using national soil atlas data and satellite imagery of flood inundation, resulting in recharge maps for seven hydrologically distinct Australian catchments. Recharge for three of the catchments was validated against independent recharge estimates from bore hydrograph responses and one catchment was additionally validated against point scale recharge modelling and catchment scale change in groundwater storage. Flood recharge was predicted for four of the seven catchments modelled, but there was also unexplained recharge present from the satellite flood inundation mapping data. At a catchment scale, recharge from overbank flooding was somewhat under predicted using the analytical equations, but there was good confidence in the spatial patterns of flood recharge produced. Due to the scale of the input data, there were no significant relationships found when compared at a point scale. Satellite derived flood inundation data and uncertainty in soil maps were the key limitations to the accuracy of the modelled recharge. Use of this method to model OFR was found to be appropriate at a catchment to continental scale, given appropriate data sources. The proportion of OFR was found to be at least 4% of total change in groundwater storage in one of the catchments for the period modelled, and at least 15% of the riparian recharge. Accounting for OFR is an important, and often overlooked, requirement for closing water balances in both the surface water and groundwater domains.

Doble, R.; Crosbie, R.; Peeters, L.; Joehnk, K.; Ticehurst, C.

2013-10-01

195

Transient heat and mass transfer modeling aspects of rechargeable lithium\\/polymer electrolyte batteries  

Microsoft Academic Search

Rechargeable lithium\\/polymer electrolyte batteries have the potential for higher energy density than existing lithium-ion type batteries. However, lithium\\/polymer batteries have limited cycle life. Discharge capacity is extremely sensitive to temperature and discharge rate, and potential safety problems exist and are related to battery temperature distribution. This dissertation addresses several of these battery performance limiting issues by modeling fundamental heat and

Joseph Phillip Fellner

1997-01-01

196

Oxidation of Unsymmmetrical Dimethyl Hydrazine over Oxide and Noble Metal Catalysts. Solution of Environmental Problems of Production, Storage and Disposal of Highly Toxic Rocket Fuels  

Microsoft Academic Search

Reduction and conversion of weapons production in Russia have made extremely urgent the problems of development and implementation\\u000a of environmentally safe and efficient processes of disposal of rocket fuel components (RFC). One of the most pressing problems\\u000a is the development of a disposal process for extremely toxic 1,1- dymethylhydrazine (unsymmetrical dimethylhydrazine -UDMH).\\u000a There are no industrial facilities for UDMH treatment

Z. Ismagilov; M. Kerzentsev; I. Ismagilov; V. Sazonov; V. Parmon; G. Elizarova; O. Pestunova; V. Shandakov; Yu. Zuev; V. Eryomin; N. Pestereva; F. Garin; H. Veringa

197

Mikrobiella Problem vid Bergrumslagring av Jetbraensle. Mikrobiologiska och Kemiska Undersoekningar i Flygdrivmedelsfoerrad (Microbial Problems in Connection with Storage of Jet Fuel in Rock Caverns. Microbiological and Chemical Investigations in Storages for Aviation Fuel).  

National Technical Information Service (NTIS)

During long-term storage of jet fuel on waterbeds in rock caverns, the fuel can become corrosive in time. The report summarizes investigations on fuel and waterbed in rock caverns. It is the production of hydrogen sulfide in the waterbed, mainly from the ...

R. Roffey A. Norqvist A. Edlund

1985-01-01

198

Phosphidation of Li4Ti5O12 nanoparticles and their electrochemical and biocompatible superiority for lithium rechargeable batteries.  

PubMed

Phosphidated-Li(4)Ti(5)O(12) shows high capacity with a significantly enhanced kinetics opening new possibilities for ultra-fast charge/discharge of lithium rechargeable batteries. The in vitro cytotoxicity test proves its fabulous cell viability, indicating that the toxicity problem of nanoparticles can be also solved by phosphidation. PMID:21952411

Jo, Mi Ru; Nam, Ki Min; Lee, Youngmin; Song, Kyeongse; Park, Joon T; Kang, Yong-Mook

2011-09-26

199

Organic electrolyte for use in a lithium rechargeable electrochemical cell and lithium rechargeable electrochemical cell including said organic electrolyte  

SciTech Connect

This invention relates in general to use of an organic electrolyte in a lithium rechargeable electrochemical cell and to a lithium rechargeable electrochemical cell including said electrolyte; and, in particular, to the use of 1 to 2 mol/dm/sup 3/ LiAsF/sub 6/ in dimethylcarbonate (DMC) or 1 to 2 mol/dm/sup 3/ LiAsF/sub 6/ in (DMC) mixtures with methyl formate (MF) in which the mass percent of the (DMC) can vary from 25 to 100 mass percent as the electrolyte in a lithium rechargeable electrochemical cell, and to a lithium rechargeable electrochemical cell including said electrolyte.

Plichta, E.J.; Slane, S.M.; Salomon, M.

1987-07-06

200

US Policy Response to the Wildfire Fuels Management Problem: An Analysis of the News Media Debate about the Healthy Forests Initiative and the Healthy Forests Restoration Act  

Microsoft Academic Search

The Healthy Forests Initiative (HFI) and Healthy Forests Restoration Act (HFRA) represent major policy and legislative responses to the wildfire fuels management problem in the USA. This study examined the nature and evolution of the news media discussion and debate about these policy initiatives. Computer content analysis was used to analyse favourable and unfavourable beliefs about HFI\\/HFRA expressed in about

Jayne Fingerman Johnson; David N. Bengston; David P. Fan

2009-01-01

201

Challenges of Artificial Recharge at the Chain of Lakes  

NASA Astrophysics Data System (ADS)

A series of gravel quarry lakes, A through I (i.e. Chain of Lakes) in Alameda County, California are planned to convert to off-channel spreading lakes for artificial groundwater recharge. An operational plan is needed for the near-term improvements that would allow safe and efficient operations of Lake H and Lake I recently acquired for artificial recharge operations. Water source for the groundwater recharge comes from State Water Project (SWP) water releases at the South Bay Aqueduct turnout. The released water flows approximately nine miles in Arroyo Mocho Creek to the planned diversion facility. The recharge system includes multiple water delivery components and recharge components. Reliability of SWP water delivery is a water supply constraint to the recharge system. Hydraulic capacities of each delivery component and recharge capacities of each recharge component are physical constraints to the development of the operational plan. Policy issues identified in the Mitigated Negative Declaration which contains mitigation measures addressing potential impacts of fisheries and erosion are regulatory constraints to the operational plan development. Our approach that addresses technical challenges and policy issues in the development of the operational plan includes i) determination of lake recharge under observed conditions using water budget method; ii) development and calibration of a ground water flow model using MODFLOW; iii) estimation of lake recharge capacity for a range of lake levels using the calibrated ground water flow model; iv) analysis of clogging layer effects on recharge capacity; and v) development and application of operations models for the stream delivery system and the lake system.

Zeng, X.

2004-12-01

202

Porous silicon nanowires for lithium rechargeable batteries  

NASA Astrophysics Data System (ADS)

Porous silicon nanowire is fabricated by a simple electrospinning process combined with a magnesium reduction; this material is investigated for use as an anode material for lithium rechargeable batteries. We find that the porous silicon nanowire electrode from the simple and scalable method can deliver a high reversible capacity with an excellent cycle stability. The enhanced performance in terms of cycling stability is attributed to the facile accommodation of the volume change by the pores in the interconnect and the increased electronic conductivity due to a multi-level carbon coating during the fabrication process.

Yoo, Jung-Keun; Kim, Jongsoon; Lee, Hojun; Choi, Jaesuk; Choi, Min-Jae; Sim, Dong Min; Jung, Yeon Sik; Kang, Kisuk

2013-10-01

203

Porous silicon nanowires for lithium rechargeable batteries.  

PubMed

Porous silicon nanowire is fabricated by a simple electrospinning process combined with a magnesium reduction; this material is investigated for use as an anode material for lithium rechargeable batteries. We find that the porous silicon nanowire electrode from the simple and scalable method can deliver a high reversible capacity with an excellent cycle stability. The enhanced performance in terms of cycling stability is attributed to the facile accommodation of the volume change by the pores in the interconnect and the increased electronic conductivity due to a multi-level carbon coating during the fabrication process. PMID:24067596

Yoo, Jung-Keun; Kim, Jongsoon; Lee, Hojun; Choi, Jaesuk; Choi, Min-Jae; Sim, Dong Min; Jung, Yeon Sik; Kang, Kisuk

2013-09-25

204

Labile Organic Carbon in Recharge and its Impact on Groundwater Arsenic Concentrations in Bangladesh  

NASA Astrophysics Data System (ADS)

Researchers have puzzled over the origin of dissolved arsenic in the aquifers of the Ganges Delta since widespread arsenic poisoning from groundwater was publicized two decades ago. Previous work has concluded that biological oxidation of organic carbon drives geochemical transformations that mobilize arsenic from sediments; however, the source of the organic carbon that fuels these processes remains controversial. A combined hydrologic and biogeochemical analysis of a typical site in Bangladesh, where constructed ponds and groundwater-irrigated rice fields are the main sources of recharge, shows that only recharge through pond sediments provides the biologically degradable organic carbon that can drive arsenic mobilization. Numerical groundwater simulations as well as chemical and isotopic indicators suggest that contaminated groundwater originates from excavated ponds and that water originating from rice fields is low in arsenic. In fact, rice fields act as an arsenic sink. Irrigation moves arsenic-rich groundwater from the aquifers and deposits it on the rice fields. Most of the deposited arsenic does not return to the aquifers; it is sorbed by the field’s surface soil and bunds, and is swept away in the monsoon floods. The findings indicate that patterns of arsenic contamination in the shallow aquifer are due to recharge-source variation and complex three-dimensional flow.

Neumann, R. B.; Ashfaque, K. N.; Badruzzaman, A. M.; Ali, M.; Shoemaker, J. K.; Harvey, C. F.

2009-12-01

205

Recharge into Southern High Plains aquifer - Possible mechanisms, unresolved questions  

Microsoft Academic Search

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

Nativ

2009-01-01

206

Generator and rechargeable battery system for pedal powered vehicles  

Microsoft Academic Search

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

Ryan

1985-01-01

207

Current collectors for rechargeable Li-Air batteries  

SciTech Connect

Here we report the negative influence of porous nickel foam for use as current collectors in rechargeable Li-air batteries. Uncoated nickel foam promotes the decomposition of LiPF6-organic carbonate electrolytes under normal charging conditions reported for rechargeable Li-air cells. We have identified Ni free porous carbon supports as more appropriate cathode current collectors.

Veith, Gabriel M [ORNL; Dudney, Nancy J [ORNL

2011-01-01

208

Hydrogeology of Regional Valley Fill Aquifers with Mountain System Recharge  

Microsoft Academic Search

Groundwater in the North Okanagan was investigated using an integrated physical, geochemical and numerical approach. The North Okanagan Groundwater Characterization and Assessment (NOGWCA) project began with an investigation of the geology and hydrostratigraphy of the North Okanagan region. The Deep Creek and Fortune Creek watersheds were found to contain multiple valley-fill aquifers which are recharged via mountain system recharge (MSR)

J. Ping; C. Nichol; A. Wei

2009-01-01

209

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

Microsoft Academic Search

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

John J. Sammarco

1989-01-01

210

Comparative analysis of piezoelectric power harvesting circuits for rechargeable batteries  

Microsoft Academic Search

Using piezoelectric materials to harvest energy from ambient vibrations to power wireless sensors has been of great interest over the past few years. Due to the power output of the piezoelectric materials is relatively low, rechargeable battery is considered as one kind of energy storage to accumulate the harvested energy for intermittent use. Piezoelectric harvesting circuits for rechargeable batteries have

Mingjie Guan; Wei-Hsin Liao

2005-01-01

211

Transcutaneous Battery Recharging By Volume Conduction and its Circuit Modeling  

Microsoft Academic Search

Many implantable devices require large capacity batteries implanted in the body. Transcutaneous battery recharging can effectively maintain the longevity of these implants. Based on this consideration we have developed a transcutaneous battery recharging circuit unit which takes advantages of skin volume conduction. This unit is able to pass 2.8 mA from the outside to the inside of pig skin with

Zhide Tang; R. J. Sclabassi; C. Sun; S. A. Hackworth; Jun Zhao; X. T. Cui; M. Sun

2006-01-01

212

Computational Aspect of Artificial Ground Water Recharging into Unconfined Aquifer  

Microsoft Academic Search

CARE FOR GROUND WATER BEFORE IT BECOMES RARE therefore CATCHES WATER IN EVERY POSSIBLE WAY AND EVERY POSSIBLE PLACE IT FALLS. Mathematical aspect of ground water flow related to unconfined aquifer and a change in saturated thickness with variation in piezometric level so, permeability k, radius of influences L, distance between two recharge wells and presence of recharge by rainfall

Pratima Patel; M. D. Desai

213

Determining the recharge mode of Sahelian aquifers using water isotopes  

Microsoft Academic Search

It is proposed that the drainage network plays an important role in the recharge process of the fractured aquifers in the African Precambrian shield and that the fractured aquifer system is likely to be hydraulically continuous; this contrasts with most previous studies, which suggested direct recharge by rainwater percolation. Two areas were selected in Niger for the study of the

Pierre Girard; Claude Hillaire-Marcel; Marie Solange Oga

1997-01-01

214

Recharge and salinization in the Madrid Basin  

NASA Astrophysics Data System (ADS)

The purpose of this work was to reinvestigate the existing hydrogeological conceptual model of the basin of Madrid, Spain. A cumulative chemical isotopic diagram which enabled the distinction between different groups of water as well as calculation of the mode of their blending was used for this investigation. It was found that the groups of discharge were lighter in their isotopic composition than that of recharge. The previous explanation of this fact, backed by carbon-14 dating, was the long residence time due to flow lines going down to depths of more than 1000 m. This flow model assumes homogenous conditions to these depths. This assumption can not be supported by evidence from deep wells. Thus a modified model is suggested which maintains homogenous conditions only to about 300 m and a deep confined aquifer below containing paleowater. The higher degree of depletion of this water has been explained by a colder climate on top of an altitude effect. Another interesting observation was the correlation between the isotopic composition of the rains, the month of the rain event and the composition of the recharge group groundwater. It could be seen that the winter rains resemble the groundwater composition, which shows that practically all the spring and summer rains were evapotranspirated.

Issar, A. S.; Llamas, R. M.; Herraez, I.

1993-04-01

215

An areal recharge and discharge simulating method for MODFLOW  

NASA Astrophysics Data System (ADS)

As a widely used groundwater flow model, MODFLOW offers a set of packages to simulate hydrologic stresses, inflows and outflows, to a groundwater system. Speci?cally, MODFLOW lacks a general method to process areally distributed recharge and discharge to groundwater. One solution would be to create a new package for MODFLOW. Alternatively, it is also possible to make the best use of existing code to the same effect. In this note, a simple, yet effective method to simulate areal recharge and discharge is proposed based on the recharge (RCH) package of MODFLOW, allowing multiple instances of the RCH package to be used in one model. The method has been implemented in MODFLOW2000/2005 and has been successfully applied to a regional groundwater flow model to simulate areally distributed precipitation recharge, agricultural discharge and irrigation infiltration recharge in a simple approach.

Dong, Yanhui; Li, Guomin; Xu, Haizhen

2012-05-01

216

Groundwater Recharge Rate and Zone Structure Estimation Using PSOLVER Algorithm.  

PubMed

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 Tahtal? 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 Tahtal? 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

Ayvaz, M Tamer; Elçi, Alper

2013-06-01

217

[Current status of air pollution in Sao Paulo, Brazil: effects and problems associated with the introduction of ethanol-fueled motor vehicles].  

PubMed

Recently suggestions have been advanced that alternative fuels including ethanol, methanol or methane instead of so called "fossil fuels" may help improve the current conditions of air pollution. According to results of general survey in Sao Paulo, since their introduction in 1978, ethanol-fueled cars have increased their share to almost 50% of all light vehicles in 1983. The current status of air pollution in Sao Paulo metropolitan area (SPMA) is described in relation to the use of such alternative fuel. The average concentrations in air of SO2 and lead have been decreasing drastically during the period of 1982-88, whereas non-methane hydrocarbon, NO2 and O3 levels have been increasing to attain the worst levels in the world as indicated in Fig. 2. The use of ethanol-fuel, which contains less sulphate and lead, is thought to have contributed more or less to the above reductions of SO2 and lead in the air. However, the pollutants that have increased may derive mainly from diesel and gasoline exhausts of heavy vehicles. The general state of air pollutions appears not to have been improved, suggesting the difficulty in resolving air pollution issues. On the other hand, a current problem specific to ethanol-fuel is the aldehydes or other carcinogenic components in exhaust. Peak formaldehyde concentration, for example, have been reported to have reached 159 ppb in SPMA, which may be one of the highest levels shown in ambient air.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1720061

Kabuto, M; Tsugane, S; Hamada, G S

1990-05-01

218

Nanocarbon networks for advanced rechargeable lithium batteries.  

PubMed

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

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

2012-09-06

219

Unlinkable Priced Oblivious Transfer with Rechargeable Wallets  

NASA Astrophysics Data System (ADS)

We present the first truly unlinkable priced oblivious transfer protocol. Our protocol allows customers to buy database records while remaining fully anonymous, i.e., (1) the database does not learn who purchases a record, and cannot link purchases by the same customer; (2) the database does not learn which record is being purchased, nor the price of the record that is being purchased; (3) the customer can only obtain a single record per purchase, and cannot spend more than his account balance; (4) the database does not learn the customer's remaining balance. In our protocol customers keep track of their own balances, rather than leaving this to the database as done in previous protocols. Our priced oblivious transfer protocol is also the first to allow customers to (anonymously) recharge their balances. Finally, we prove our protocol secure in the standard model (i.e., without random oracles).

Camenisch, Jan; Dubovitskaya, Maria; Neven, Gregory

220

Spinel electrodes for rechargeable lithium batteries.  

SciTech Connect

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).

Thackeray, M. M.

1999-11-10

221

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

PubMed

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

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

2013-05-01

222

Using atmospheric tracers to reduce uncertainty in groundwater recharge areas.  

PubMed

A Monte Carlo-based approach to assess uncertainty in recharge areas shows that incorporation of atmospheric tracer observations (in this case, tritium concentration) and prior information on model parameters leads to more precise predictions of recharge areas. Variance-covariance matrices, from model calibration and calculation of sensitivities, were used to generate parameter sets that account for parameter correlation and uncertainty. Constraining parameter sets to those that met acceptance criteria, which included a standard error criterion, did not appear to bias model results. Although the addition of atmospheric tracer observations and prior information produced similar changes in the extent of predicted recharge areas, prior information had the effect of increasing probabilities within the recharge area to a greater extent than atmospheric tracer observations. Uncertainty in the recharge area propagates into predictions that directly affect water quality, such as land cover in the recharge area associated with a well and the residence time associated with the well. Assessments of well vulnerability that depend on these factors should include an assessment of model parameter uncertainty. A formal simulation of parameter uncertainty can be used to delineate probabilistic recharge areas, and the results can be expressed in ways that can be useful to water-resource managers. Although no one model is the correct model, the results of multiple models can be evaluated in terms of the decision being made and the probability of a given outcome from each model. PMID:21416662

Starn, J Jeffrey; Bagtzoglou, Amvrossios C; Robbins, Gary A

223

Quantifying the modern recharge of the "fossil" Sahara aquifers  

NASA Astrophysics Data System (ADS)

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.

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

2013-06-01

224

Geostatistical estimates of future recharge for the Death Valley region  

SciTech Connect

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.

Hevesi, J.A. [Geological Survey, Las Vegas, NV (United States); Flint, A.L. [Geological Survey, Sacramento, CA (United States)

1998-12-01

225

Aquifer recharging in South Carolina: radiocarbon in environmental hydrogeology  

SciTech Connect

Radiocarbon activities of dissolved inorganic carbon (and tritium activities where infiltration rates are rapid and aquifers shallow) provide relatively unambiguous and inexpensive evidence for identification of significant recharge areas. Such evidence is for the actual occurrence of modern recharge in the aquifer and thus is less inferential than stratigraphic or potentiometric evidence. These underutilized isotopic techniques are neither arcane nor complex and have been more-or-less standardized by earlier researchers. In South Carolina, isotopic evidence has been used from both calcareous and siliceous sedimentary aquifers and fractured crystalline rock aquifers. The Tertiary limestone aquifer is shown not to be principally recharged in its subcrop area, unlike conditions assumed for many other sedimentary aquifers in southeastern United States, and instead receives considerable lateral recharge from interfingering updip Tertiary sand aquifers in the middle coastal plain. Induced recharging at Hilton Head Island is mixing ancient relict water and modern recharge water. Recharging to deeper portions of the Cretaceous Middendorf basal sand aquifer occurs at least as far coastward as the middle coastal plain, near sampling sites that stratigraphically appear to be confined. Pronounced mineralization of water in fractured rocks cannot be considered as evidence of ancient or relict ground water that is isolated from modern contaminants, some of these waters contain considerable radiocarbon and hydrogen-bomb tritium.

Stone, P.A.; Knox, R.L.; Mathews, T.D.

1985-01-01

226

Echo Meadows Project Winter Artificial Recharge.  

SciTech Connect

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.

Ziari, Fred

2002-12-19

227

Effects of artificial recharge on the Ogallala aquifer, Texas  

USGS Publications Warehouse

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.

Brown, Richmond Flint; Keys, W. S.

1985-01-01

228

A 2-D Test Problem for CFD Modeling Heat Transfer in Spent Fuel Transfer Cask Neutron Shields  

Microsoft Academic Search

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

Ghani Zigh; Jorge Solis; James A. Fort

2011-01-01

229

Microbial problems in connection with storage of jet fuel in rock caverns. Development of a process for purification of corrosive jet fuel). Mikrobiella problem vid bergrumslagring av jetbraensle. Utveckling av process foer rening av korrosivt jetbraensle  

SciTech Connect

The literature concerning desulfurization is summarized. Investigations concerning the use of different compounds in order to purify corrosive jet fuel are described. A process for purification of corrosive jet fuel with 1-5 mg/l elemental sulphur was developed which is based on powdered silver as adsorbent. The capacity for adsorption was determined. On the basis of the data obtained, a scale-up was carried out to a full scale plant. The plant was planned for a capacity of 100 - 300 mT fuel/hour and so that it can be constructed as a mobile unit enabling it to be transported to various storage plants.

Roffey, R.

1985-06-01

230

Ground-water recharge from streamflow data, NW Florida  

USGS Publications Warehouse

Annual base flows of streams draining Okaloosa County and adjacent areas in northwest Florida were determined through hydrograph separation and correlation techniques for purposes of evaluating variations in ground-water recharge rates. Base flows were least in the northern part of the county and greatest in the southern part. Topographic and soils data were then superimposed on the distribution of base flow by subbasin to produce a map showing distribution of ground-water recharge throughout the county. The highest recharge rate occurs in the southern part of the county where relatively flat upland areas underlain by excessively drained sandy soils result in minimal storm runoff and evapotranspiration.

Vecchioli, John; Bridges, W. C.; Rumenik, R. P.; Grubbs, J. W.

1991-01-01

231

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

NASA Astrophysics Data System (ADS)

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.

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

2011-12-01

232

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

NASA Astrophysics Data System (ADS)

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.

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

2013-06-01

233

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

NASA Astrophysics Data System (ADS)

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 ?M to 100 ?M 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.

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

2008-12-01

234

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

SciTech Connect

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.

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

2010-10-27

235

Fossil Fuels.  

ERIC Educational Resources Information Center

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…

Crank, Ron

236

Fossil Fuels.  

ERIC Educational Resources Information Center

|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…

Crank, Ron

237

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 ...

238

Solid polymer electrolytes for rechargeable batteries. Final report.  

National Technical Information Service (NTIS)

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 tetmethylortho...

S. C. Narang S. C. Ventura

1992-01-01

239

Intrinsically Safe 5-V, 4-A: Rechargeable Power Supply.  

National Technical Information Service (NTIS)

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 haz...

J. J. Sammarco

1989-01-01

240

Lithium Rechargeable Cell With a Poly 3-Methylthiophene Cathode.  

National Technical Information Service (NTIS)

A poly 3-methylthiophene (PMT) cathode showed excellent coulombic efficiency during cycling in a lithium rechargeable cell. An electrolyte containing dimethyl carbonate was used since it is stable at the high anodic potentials reached during cell charging...

C. W. Walker S. M. Slane

1992-01-01

241

Spatial and temporal variations in seepage during managed aquifer recharge  

NASA Astrophysics Data System (ADS)

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.

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

2009-12-01

242

Electrochemical behavior of hydrated molybdenum oxides in rechargeable lithium batteries  

Microsoft Academic Search

Oxide-hydrates of molybdenum (OHM) are investigated as 3-volt cathode materials for rechargeable lithium batteries. These\\u000a materials with different water content showed a much better performance than that of MoO3 as cathode of the rechargeable lithium battery. We report the electrochemical characteristics of Li\\/\\/OHM batteries using\\u000a the oxides and oxide-hydrates of molybdenum which were synthesized from molybdic acid. The oxide has

B. Yebka; C. Julien; G. A. Nazri

1999-01-01

243

Estimating Regional Groundwater Recharge Using a Hydrological Budget Method  

Microsoft Academic Search

Estimating groundwater recharge is a key component in determining the sustainable yield of groundwater resources in arid and\\u000a semi-arid areas such as southern California. Estimating groundwater recharge on a regional scale requires developing a water\\u000a budget that incorporates data on boundary conditions, aquifer properties, groundwater levels, and groundwater production.\\u000a The hydrological budget method proposed herein is simple, cost-effective, and easy

Fakhri Manghi; Behrooz Mortazavi; Christie Crother; Moshrik R. Hamdi

2009-01-01

244

Ground water recharge and flow characterization using multiple isotopes.  

PubMed

Stable isotopes of delta(18)O, delta(2)H, and (13)C, radiogenic isotopes of (14)C and (3)H, and ground water chemical compositions were used to distinguish ground water, recharge areas, and possible recharge processes in an arid zone, fault-bounded alluvial aquifer. Recharge mainly occurs through exposed stream channel beds as opposed to subsurface inflow along mountain fronts. This recharge distribution pattern may also occur in other fault-bounded aquifers, with important implications for conceptualization of ground water flow systems, development of ground water models, and ground water resource management. Ground water along the mountain front near the basin margins contains low delta(18)O, (14)C (percent modern carbon [pmC]), and (3)H (tritium units [TU]), suggesting older recharge. In addition, water levels lie at greater depths, and basin-bounding faults that locally act as a flow barrier may further reduce subsurface inflow into the aquifer along the mountain front. Chemical differences in ground water composition, attributed to varying aquifer mineralogy and recharge processes, further discriminate the basin-margin and the basin-center water. Direct recharge through the indurated sandstones and mudstones in the basin center is minimal. Modern recharge in the aquifer is mainly through the broad, exposed stream channel beds containing coarse sand and gravel where ground water contains higher delta(18)O, (14)C (pmC), and (3)H (TU). Spatial differences in delta(18)O, (14)C (pmC), and (3)H (TU) and occurrences of extensive mudstones in the basin center suggest sluggish ground water movement, including local compartmentalization of the flow system. PMID:18384592

Chowdhury, Ali H; Uliana, Matthew; Wade, Shirley

2008-04-02

245

Recharge signal identification based on groundwater level observations.  

PubMed

This study applied a method of the rotated empirical orthogonal functions to directly decompose the space-time groundwater level variations and determine the potential recharge zones by investigating the correlation between the identified groundwater signals and the observed local rainfall records. The approach is used to analyze the spatiotemporal process of piezometric heads estimated by Bayesian maximum entropy method from monthly observations of 45 wells in 1999-2007 located in the Pingtung Plain of Taiwan. From the results, the primary potential recharge area is located at the proximal fan areas where the recharge process accounts for 88% of the spatiotemporal variations of piezometric heads in the study area. The decomposition of groundwater levels associated with rainfall can provide information on the recharge process since rainfall is an important contributor to groundwater recharge in semi-arid regions. Correlation analysis shows that the identified recharge closely associates with the temporal variation of the local precipitation with a delay of 1-2 months in the study area. PMID:22016042

Yu, Hwa-Lung; Chu, Hone-Jay

2011-10-21

246

Estimating aquifer channel recharge using optical data interpretation.  

PubMed

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

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

2011-03-24

247

Within-Day Recharge of Plug-In Hybrid Electric Vehicles: Energy Impact of Public Charging Infrastructure  

SciTech Connect

This paper examines the role of public charging infrastructure in increasing the share of driving on electricity that plug-in hybrid electric vehicles might exhibit, thus reducing their gasoline consumption. Vehicle activity data obtained from a global positioning system tracked household travel survey in Austin, Texas, is used to estimate gasoline and electricity consumptions of plug-in hybrid electric vehicles. Drivers within-day recharging behavior, constrained by travel activities and public charger availability, is modeled. It is found that public charging offers greater fuel savings for hybrid electric vehicles s equipped with smaller batteries, by encouraging within-day recharge, and providing an extensive public charging service is expected to reduce plug-in hybrid electric vehicles gasoline consumption by more than 30% and energy cost by 10%, compared to the scenario of home charging only.

Dong, Jing [ORNL; Lin, Zhenhong [ORNL

2012-01-01

248

Recharge to the North Richland well field  

SciTech Connect

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.

Law, A.G.

1989-07-01

249

Characterization of AA size lithium rechargeable cells  

NASA Astrophysics Data System (ADS)

Testing of AA size rechargeable cells for underwater vehicle and other naval applications is complete for AT&T's lithium/niobium triselenide (Li/NbSe3) and Moli Energy's lithium/molybdenum disulfide (Li/MoS2) and in progress on Moli Energy's lithium/manganese dioxide (Li/MnO2) and W. R. Grace's lithium/titanium disulfide (Li/TiS2). Cell cycling was performed at various discharge rates, temperatures, and depths of discharge. At 25 C and 1 mA/cm2 (roughly the C/4 rate), delivered energy densities were about 40 Wh/lb for NbSe3, TiS2, and MnO2 and 22 Wh/lb for MoS2. Under the same conditions, nickel/cadmium (Ni/Cd) cells deliver only 10 Wh/lb. However Ni/Cd cycles much longer and the lithium cells are far more vulnerable than Ni/Cd to performance loss in low temperature, high discharge rate cycling. The NbSe3 data and the (limited) TiS2 data indicate that these cells tend to accept excessive charge which is often associated with lithium dendrite shorting and considered potentially hazardous. At 1 mA/cm2 and 25 C, discharge plateaus ranged from 2.9 V for MnO2 to 1.8 V for MoS2.

Murphy, T. C.; Cason-Smith, D. M.; James, S. D.; Smith, P. H.

250

Rechargeable lithiated thin film intercalation electrode battery  

SciTech Connect

This patent describes a rechargeable lithium battery, it comprises: an electrode providing a source of lithium ions, an electrolyte, and a counter-electrode consisting essentially of a lithiated transition metal oxide intercalation compound selected from the class consisting of LiMn{sub 2}O{sub 4}, LiCoO{sub 2} and LiNiO{sub 2} characterized in that the counter-electrode consists essentially of a thin film of the intercalation compound prepared by situating a suitable coating substrate in an air-tight enclosure with a supply of the lithiated metal oxide; establishing within the enclosure a low pressure, carbon-free atmosphere; vaporizing at least a portion of the metal oxide; condensing the metal oxide vapor on a surface of the substrate in a coating having a thickness in the range of about 1 to 5 micrometers; and heating the coating within the atmosphere at a temperature and for a time sufficient to convert the coating to crystallites of the metal oxide having a grain size in the range of about 0.05 to 0.1 micrometer.

Shokoohi, F.K.; Tarascon, J.M.

1992-05-05

251

Fuel substitution and efficient woodstoves: Are they the answers to the fuelwood supply problem in Northern Nigeria?  

NASA Astrophysics Data System (ADS)

Fuelwood consumption in Northern Nigeria exceeds the sustainable production, and the deficit is currently met through long-distance transport from the southern part of the country at an artificially low cost Current household fuel consumption patterns and factors affecting stove choice are discussed. Little has been done to promote more efficient woodstoves in the region, but prospects for stove programs are only good where fuelwood is marketed and the policy environment is conducive. At subsidized official prices for kerosene, liquefied petroleum gas (LPG), and electricity, wood is more expensive on a net usable heat basis, but the high capital cost of stoves for these fuels prevents many households from switching. Moreover, these fuels are often only available at much higher parallel market prices, which result in wood being the less expensive choice. There is little prospect for substitution of coal, solar cookers, or biogas digesters.

Hyman, Eric L.

1994-01-01

252

Rechargeable lithium-inorganic electrolyte cell. Quarterly report No. 2, 1 December 1989-28 February 1990  

SciTech Connect

The overall objective of the present contract research is to develop and improve performance of Li/SO2Cl2 rechargeable cells with particular emphasis on: safety, discharge capacity, and cycle life. In order to achieve these objectives the author's approach is to investigate the chemistry of Li/SO2Cl2 system with different carbon cathode materials, to optimize the cathode structure, to minimize the anode corrosion problem and to examine the effects of electrochemical parameters on cycle performance.

Hossain, S.; Harris, P.; McDonald, R.; Todino, C.; Witter, R.

1990-02-28

253

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

NASA Astrophysics Data System (ADS)

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.

Jacks, Gunnar; Kumanova, Xhume; Marku, Sonila

2013-04-01

254

A new approach to the use of genetic algorithms to solve the pressurized water reactor's fuel management optimization problem  

Microsoft Academic Search

A Genetic Algorithm (GA) based system, coupling the computer codes GENESIS 5.0 and ANC through the interface ALGER has been developed aiming at pressurized water reactor's (PWR) fuel management optimization. An innovative codification, the List Model (LM), has been incorporated into the system. LM avoids the use of heuristic crossover operators and only generates valid nonrepetitive loading patterns in the

Jorge Luiz C Chapot; Fernando Carvalho Da Silva; Roberto Schirru

1999-01-01

255

Fate of human viruses in groundwater recharge systems  

SciTech Connect

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.

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

1980-03-01

256

Transcutaneous battery recharging by volume conduction and its circuit modeling.  

PubMed

Many implantable devices require large capacity batteries implanted in the body. Transcutaneous battery recharging can effectively maintain the longevity of these implants. Based on this consideration we have developed a transcutaneous battery recharging circuit unit which takes advantages of skin volume conduction. This unit is able to pass 2.8 mA from the outside to the inside of pig skin with a current transmitting efficiency of 27%. Theoretical analysis and experiments have validated that this battery recharging technology is an effective approach. In this research we have constructed an x-type equivalent circuit model of skin volume conduction for battery recharging. The parameters of the x-type equivalent circuit can be easily measured and used to evaluate the battery charging system characteristics, such as the rechargeable prerequisite and the current transmitting efficiency limitation. We have analyzed the transcutaneous current transmitting efficiency by applying the x-type equivalent circuit model and discussed approaches for enhancing current transmitting efficiency. PMID:17945991

Tang, Zhide; Sclabassi, Robert J; Sun, Caixin; Hackworth, Steven A; Zhao, Jun; Cui, Xinyan T; Sun, Mingui

2006-01-01

257

Delineating volcanic aquifer recharge areas using geochemical and isotopic tools  

NASA Astrophysics Data System (ADS)

Relative recharge areas are evaluated using geochemical and isotopic tools, and inverse modeling. Geochemistry and water quality in springs discharging from a volcanic aquifer system in Guatemala are related to relative recharge area elevations and land use. Plagioclase feldspar and olivine react with volcanically derived CO2 to produce Ca-montmorillonite, chalcedony and goethite in the groundwater. Alkalinity, Mg, Ca, Na, and SiO2(aq) are produced, along with minor increases in Cl and SO4 concentrations. Variations in groundwater ?D and ?18O values are attributed to recharge elevation and used in concert with geochemical evolution to distinguish local, intermediate, and regional flow systems. Springs with geochemically inferred short flow paths provided useful proxies to estimate an isotopic gradient for precipitation (-0.67 ?18O/100 m). No correlation between spring discharge and relative flow-path length or interpreted recharge elevation was observed. The conceptual model was consistent with evidence of anthropogenic impacts (sewage and manure) in springs recharged in the lower watershed where livestock and humans reside. Spring sampling is a low-budget approach that can be used to develop a useful conceptual model of the relative scale of groundwater flow (and appropriate watershed protection areas), particularly in volcanic terrain where wells and boreholes are scarce.

Mulligan, Brendan M.; Ryan, M. Cathryn; Cámbara, Tomás Padilla

2011-11-01

258

Fuel dehazers  

SciTech Connect

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.

Lyons, W.R.

1986-03-01

259

Heat transport in the vicinity of an artificial recharge site  

NASA Astrophysics Data System (ADS)

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

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

2010-05-01

260

Estimating ground water recharge from topography, hydrogeology, and land cover.  

PubMed

Proper management of ground water resources requires knowledge of the rates and spatial distribution of recharge to aquifers. This information is needed at scales ranging from that of individual communities to regional. This paper presents a methodology to calculate recharge from readily available ground surface information without long-term monitoring. The method is viewed as providing a reasonable, but conservative, first approximation of recharge, which can then be fine-tuned with other methods as time permits. Stream baseflow was measured as a surrogate for recharge in small watersheds in southeastern Wisconsin. It is equated to recharge (R) and then normalized to observed annual precipitation (P). Regression analysis was constrained by requiring that the independent and dependent variables be dimensionally consistent. It shows that R/P is controlled by three dimensionless ratios: (1) infiltrating to overland water flux, (2) vertical to lateral distance water must travel, and (3) percentage of land cover in the natural state. The individual watershed properties that comprise these ratios are now commonly available in GIS data bases. The empirical relationship for predicting R/P developed for the study watersheds is shown to be statistically viable and is then tested outside the study area and against other methods of calculating recharge. The method produces values that agree with baseflow separation from streamflow hydrographs (to within 15% to 20%), ground water budget analysis (4%), well hydrograph analysis (12%), and a distributed-parameter watershed model calibrated to total streamflow (18%). It has also reproduced the temporal variation over 5 yr observed at a well site with an average error < 12%. PMID:15726928

Cherkauer, Douglas S; Ansari, Sajjad A

261

Evaluation of Methods for Estimation of Aquifer Recharge from Precipitation on Semi-Arid Lands.  

National Technical Information Service (NTIS)

Precipitation falling on semi-arid, non-irrigated lands may represent a significant percentage of total aquifer recharge in areas such as the eastern Snake River Plain in southern Idaho. Direct measurement of precipitation recharge is usually not feasible...

G. S. Johnson C. E. Brockway A. Coiner

1985-01-01

262

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...

263

SPATIAL SCALING OF SURFACE WATER INFILTRATION AND ITS IMPLICATIONS FOR ESTIMATING GROUNDWATER RECHARGE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The GRAPHIC Project has identified priority research topics related to groundwater recharge, discharge, storage, and water quality. This presentation focuses on some physical aspects affecting spatial groundwater recharge estimation and uncertainty associated with spatial variability. Previous wor...

264

Rechargeable Zn-MnO sub 2 alkaline batteries  

SciTech Connect

In this paper progress in the development of rechargeable alkaline zinc-manganese dioxide cells is described. The advantages and limitations of the system are evaluated. Laboratory tests run on commercial primary alkaline cells as well as model simulations of a bipolar MnO{sub 2} electrode show that the rechargeable alkaline battery may be able to compete with lead-acid, nickel-cadmium, and secondary lithium cells for low- to moderate-rate applications. However, because of this poor performance at high rates and low temperatures, the alkaline MnO{sub 2} battery is not suitable for present automotive starting applications.

Wruck, W.J.; Reichman, B.; Bullock, K.R.; Kao, W.H. (Corporate Applied Research, Johnson Controls, Inc., Milwaukee, WI (US))

1991-12-01

265

Modelling of recharge and pollutant fluxes to urban groundwaters.  

PubMed

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

Thomas, Abraham; Tellam, John

2005-12-01

266

Energy harvesting by implantable abiotically catalyzed glucose fuel cells  

Microsoft Academic Search

Implantable glucose fuel cells are a promising approach to realize an autonomous energy supply for medical implants that solely relies on the electrochemical reaction of oxygen and glucose. Key advantage over conventional batteries is the abundant availability of both reactants in body fluids, rendering the need for regular replacement or external recharging mechanisms obsolete. Implantable glucose fuel cells, based on

S. Kerzenmacher; J. Ducrée; R. Zengerle; F. von Stetten

2008-01-01

267

60/240 Watt Hydrazine Fuel Cell System.  

National Technical Information Service (NTIS)

A portable hybrid fuel cell-storage battery system is described. Such a system allows short periods of high power drain from a nickel-cadmium battery which is recharged by a hydrazine air fuel cell. The casing, power output, electrical characteristics, an...

L. J. Rogers

1968-01-01

268

Competitive systems - Ambient temperature rechargeable batteries  

NASA Astrophysics Data System (ADS)

Recent in designs of aqueous electrolyte secondary batteries are presented. Operation principles, performance characteristics, and applications of various types of lead/acid batteries, alkaline electrolyte batteries, flow batteries, and battery/fuel cell hybrids (such as metal/air and hydrogen/metal oxide systems) are discussed. Consideration is given to the relative importance of such battery parameters as deep discharge capability, freedom from maintenance, shelf life, and cost, depending upon the specific application.

dell, R. M.

269

Temporal and spatial variability of groundwater recharge on Jeju Island, Korea  

NASA Astrophysics Data System (ADS)

Baseline mean island-wide groundwater recharge was computed as 884 mm year-1.Baseline recharge rate was computed as 42% and below previous estimates of 44-48%.Recharge estimates are conservative and do not include irrigation or other sources.

Mair, Alan; Hagedorn, Benjamin; Tillery, Suzanne; El-Kadi, Aly I.; Westenbroek, Stephen; Ha, Kyoochul; Koh, Gi-Won

2013-09-01

270

Assessing the Impact of Land Use on Groundwater Recharge in the Southern High Plains  

Microsoft Academic Search

Although it is widely recognized that land use and land use changes can have a significant impact on the near surface water budget and groundwater recharge, field studies documenting the impact of land use on recharge are limited. The purpose of this study was to determine the role of land use on groundwater recharge using electromagnetic induction, soil physics (water

R. C. Reedy; B. R. Scanlon

2003-01-01

271

Impact of Land use Change From Natural to Agricultural Ecosystems on Groundwater Recharge  

Microsoft Academic Search

Recharge is a critical component of the water cycle for groundwater resources. The purpose of this study was to evaluate the impact of land use changes from natural to agricultural ecosystems on groundwater recharge in the Amargosa Desert, Nevada and Southern High Plains, Texas. A variety of approaches were used to evaluate groundwater recharge, including noninvasive electromagnetic induction, matric potential

B. R. Scanlon; R. C. Reedy; D. A. Stonestrom

2004-01-01

272

A battery recharge model for WSNs using Free-Space Optics (FSO)  

Microsoft Academic Search

One of the most critical limiting factor for a Wireless Sensor Network (WSN) is its battery life. Therefore, a very desirable feature of WSN would be its rechargability to remain operational over longer period of times. However, the nodes needing recharge may not be accessible. In this paper, we present a battery recharge model in WSNs for inaccessible or hard

Muhammd Imran Afzal; Waqar Mahmood; Ali Hammad Akbar

2008-01-01

273

Control circuit for a solar-powered rechargeable power source and load  

SciTech Connect

A solar rechargeable apparatus is described comprising: a rechargeable power source; a solar panel connected to the rechargeable power source for supplying a charging current to the rechargeable power source; a device connected between the rechargeable power source and the solar panel to prevent discharge of current from the rechargeable power source to the solar panel; a load; and a switching circuit connected between the load and the rechargeable power source and responsive to the potential of the solar panel and the potential of the rechargeable power source, the switching circuit operatively adapted to permit current to flow from the rechargeable power source through the load when the potential across the solar panel is less than the potential across the rechargeable power source, and further in which the switching circuit is further characterized as operatively adapted to permit current to flow from the rechargeable power source through the load when the potential across the solar panel is less than the combined potential across the rechargeable power source and a predetermined potential.

Janda, R.W.; Douglas, J.L.; Condon, E.F. Jr.

1993-06-22

274

Role of vegetation in interplay of climate, soil and groundwater recharge in a global dataset  

NASA Astrophysics Data System (ADS)

Groundwater is an essential resource for people and ecosystems worldwide. Our capacity to ameliorate predicted global water shortages and to maintain sustainable water supplies depend on a better understanding of the controls of recharge and how vegetation change may affect recharge mechanisms. The goals of this study are to quantify the importance of vegetation as a dominant control on recharge globally and to compare the importance of vegetation with other hydrologically important variables, including climate and soil. We based our global analysis on > 500 recharge estimates from the literature that contained information on vegetation, soil and climate or location. Plant functional types significantly affected groundwater recharge rates substantially. After climatic factors (water inputs, PET, and seasonality), vegetation types explained about 15% of the residuals in the dataset. Across all climatic factors, croplands had the highest recharge rates, followed by grasslands, scrublands and woodlands (average recharge: 75, 63, 30, 22 mm/yr respectively). Recharge under woodlands showed the most nonlinear response to water inputs. Differences in recharge between the vegetation types were more exaggerated at arid climates and in clay soils, indicating greater biological control on soil water fluxes in these conditions. Our results shows that vegetation greatly affects recharge rates globally and alters relationship between recharge and physical variables allowing us to better predict recharge rates globally.

Kim, J. H.; Jackson, R. B.

2010-12-01

275

Potential climate change effects on groundwater recharge in the High Plains Aquifer, USA  

NASA Astrophysics Data System (ADS)

Considering that past climate changes have significantly impacted groundwater resources, quantitative predictions of climate change effects on groundwater recharge may be valuable for effective management of future water resources. This study used 16 global climate models (GCMs) and three global warming scenarios to investigate changes in groundwater recharge rates for a 2050 climate relative to a 1990 climate in the U.S. High Plains region. Groundwater recharge was modeled using the Soil-Vegetation-Atmosphere-Transfer model WAVES for a variety of soil and vegetation types representative of the High Plains. The median projection under a 2050 climate includes increased recharge in the Northern High Plains (+8%), a slight decrease in the Central High Plains (-3%), and a larger decrease in the Southern High Plains (-10%), amplifying the current spatial trend in recharge from north to south. There is considerable uncertainty in both the magnitude and direction of these changes in recharge projections. Predicted changes in recharge between dry and wet future climate scenarios encompass both an increase and decrease in recharge rates, with the magnitude of this range greater than 50% of current recharge. On a proportional basis, sensitivity of recharge to changes in rainfall indicates that areas with high current recharge rates are least sensitive to change in rainfall and vice versa. Sensitivity analyses indicate an amplification of change in recharge compared to change in rainfall, and this amplification is in the range of 1-6 with an average of 2.5-3.5 depending upon the global warming scenario.

Crosbie, Russell S.; Scanlon, Bridget R.; Mpelasoka, Freddie S.; Reedy, Robert C.; Gates, John B.; Zhang, Lu

2013-07-01

276

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 ...

277

PRIORITY POLLUTANTS IN THE CEDAR CREEK WASTEWATER RECLAMATION - RECHARGE FACILITIES  

EPA Science Inventory

The Cedar Creek Wastewater Reclamation Plant (CCWRP) located in Nassau County, NY is a 0.24 cu m/s (5.5 mgd) advanced wastewater treatment (AWT) plant designed to produce a high quality effluent suitable for groundwater recharge. The CCWRP was constructed as a demonstration proje...

278

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...

279

Moderate temperature rechargeable NaNiS2 cells  

Microsoft Academic Search

A rechargeable sodium battery of the configuration, liquid Na\\/beta double prime -Al2O3\\/molten NaAlCl4, NiS2, operating in the temperature range of 170 to 190 C, is described. This battery is capable of delivering or = to 50 W-hr\\/1b and 1000 deep discharge\\/charge cycles.

K. M. Abraham

1983-01-01

280

Moderate temperature rechargeable NaNiS2 cells  

NASA Astrophysics Data System (ADS)

A rechargeable sodium battery of the configuration, liquid Na/beta double prime -Al2O3/molten NaAlCl4, NiS2, operating in the temperature range of 170 to 190 C, is described. This battery is capable of delivering or = to 50 W-hr/1b and 1000 deep discharge/charge cycles.

Abraham, K. M.

1983-10-01

281

Effects of recharge wells and flow barriers on seawater intrusion.  

PubMed

The installation of recharge wells and subsurface flow barriers are among several strategies proposed to control seawater intrusion on coastal groundwater systems. In this study, we performed laboratory-scale experiments and numerical simulations to determine the effects of the location and application of recharge wells, and of the location and penetration depth of flow barriers, on controlling seawater intrusion in unconfined coastal aquifers. We also compared the experimental results with existing analytical solutions. Our results showed that more effective saltwater repulsion is achieved when the recharge water is injected at the toe of the saltwater wedge. Point injection yields about the same repulsion compared with line injection from a screened well for the same recharge rate. Results for flow barriers showed that more effective saltwater repulsion is achieved with deeper barrier penetration and with barriers located closer to the coast. When the flow barrier is installed inland from the original toe position however, saltwater intrusion increases with deeper barrier penetration. Saltwater repulsion due to flow barrier installation was found to be linearly related to horizontal barrier location and a polynomial function of the barrier penetration depth. PMID:20533955

Luyun, Roger; Momii, Kazuro; Nakagawa, Kei

282

Rechargeable lithium batteries in the Navy-policy and protocol  

Microsoft Academic Search

Rechargeable lithium batteries are an emerging technology that is finding widespread use in a myriad of 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

Julie A. Banner; Clinton S. Winchester

1996-01-01

283

Application of electrochemically formed polyazulene to rechargeable lithium battery  

Microsoft Academic Search

An electrochemically formed polyazulene(PAz), one of the electroconductive polycyclic hydrocarbons, was studied for its electrochemical properties in order to examine the possibility of utilizing it as a cathode active material of rechargeable lithium battery. The electrode kinetics of PAz film electrode, especially the anion doping-undoping process, were investigated mainly with cyclic voltammetry and FFT impedance method. The cyclic voltammetric results

Tetsuya Osaka; K. Naoi; T. Hirabayashi

1987-01-01

284

GIS for the assessment of the groundwater recharge potential zone  

NASA Astrophysics Data System (ADS)

Water resources in Taiwan are unevenly distributed in spatial and temporal domains. Effectively utilizing the water resources is an imperative task due to climate change. At present, groundwater contributes 34% of the total annual water supply and is an important fresh water resource. However, over-exploitation has decreased groundwater availability and has led to land subsidence. Assessing the potential zone of groundwater recharge is extremely important for the protection of water quality and the management of groundwater systems. The Chih-Pen Creek basin in eastern Taiwan is examined in this study to assess its groundwater resources potential. Remote sensing and the geographical information system (GIS) are used to integrate five contributing factors: lithology, land cover/land use, lineaments, drainage, and slope. The weights of factors contributing to the groundwater recharge are derived using aerial photos, geology maps, a land use database, and field verification. The resultant map of the groundwater potential zone demonstrates that the highest recharge potential area is located towards the downstream regions in the basin because of the high infiltration rates caused by gravelly sand and agricultural land use in these regions. In contrast, the least effective recharge potential area is in upstream regions due to the low infiltration of limestone.

Yeh, Hsin-Fu; Lee, Cheng-Haw; Hsu, Kuo-Chin; Chang, Po-Hsun

2009-07-01

285

GIS for the Assessment of the Groundwater Recharge Potential Zone  

NASA Astrophysics Data System (ADS)

Water resources in Taiwan are unevenly distributed in spatial and temporal domains. Effectively utilizing the water resources is an imperative task due to climate change. At present, groundwater contributes 34% of the total annual water supply and is an important fresh water resource. However, over-exploitation has decreased groundwater availability and has led to land subsidence. Assessing the potential zone of groundwater recharge is extremely important for the protection of water quality and the management of groundwater systems. The Chih-Pen Creek basin in eastern Taiwan is examined in this study to assess its groundwater resources potential. Remote sensing and the Geographical Information System (GIS) are used to integrate five contributing factors: lithology, land cover/land use, lineaments, drainage, and slope. The weights of factors contributing to the groundwater recharge are derived using aerial photos, geology maps, a land use database, and field verification. The resultant map of the groundwater potential zone demonstrates that the highest recharge potential area is located towards the downstream regions in the basin because of the high infiltration rates caused by gravelly sand and agricultural land use in these regions. In contrast, the least effective recharge potential area is in upstream regions due to the low infiltration of limestone.

Lee, C.; Yeh, H.; Chen, J.; Hsu, K.

2008-12-01

286

Bubble plumes generated during recharge of basaltic magma reservoirs  

Microsoft Academic Search

CO2 is relatively insoluble in basaltic magma at low crustal pressures. It therefore exists as a gas phase in the form of bubbles in shallow crustal reservoirs. Over time these bubbles may separate gravitationally from the magma in the chamber. As a result, any new magma which recharges the chamber from deeper in the crust may be more bubble-rich and

J. C. Phillips; A. W. Woods

2001-01-01

287

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...

288

System and circuit for charging a rechargeable battery  

Microsoft Academic Search

A system and circuit for charging a rechargeable battery from an external source of direct current is provided wherein the circuit includes an indicator for indicating the passage of charge current through the circuit. The circuit precludes the indicator from providing a false indication of the passage of charging current.

Mullersman

1984-01-01

289

System and circuit for charging a rechargeable battery  

SciTech Connect

A system and circuit for charging a rechargeable battery from an external source of direct current is provided wherein the circuit includes an indicator for indicating the passage of charge current through the circuit. The circuit precludes the indicator from providing a false indication of the passage of charging current.

Mullersman, F. H.

1984-12-25

290

Rechargeable battery and electrical circuit for charging thereof  

SciTech Connect

This patent describes a nickel-cadmium rechargeable cell for use in an energy-using device having at least one charging terminal contact for recharging the cell. The energy-using device adapted to alternately receive either a standard cylindrical AA, AAA, C or D size non-rechargeable cell has a pair of power terminal contacts spaced apart by a standard distance. The rechargeable cell comprises: a hollow cylindrical cell container one end of which provides an axially facing negative power terminal contact; a cell cover disposed at the other end of the cylindrical cell and electrically insulated form the container and the cover cooperating with the container to seal the interior of the cell from the environment external thereto. The cover has a positive power terminal contact surface spaced apart from the negative power terminal contact by a distance equal to the standard distance, the cover further having a terminal extension carried by the cover and extending axially away from the cell container. The terminal extension has a terminal extension charging contact surface adapted to engage the charging terminal contact of the energy-using device, the surface spaced apart from the negative power terminal contact by a distance greater than the standard distance.

Toops, K.E.

1987-02-24

291

A Wireless Power Interface for Rechargeable Battery Operated Medical Implants  

Microsoft Academic Search

This brief presents a highly integrated wirelessly powered battery charging circuit for miniature lithium (Li)-ion rechargeable batteries used in medical implant applications. An inductive link and integrated Schottky barrier rectifying diodes are used to extract the DC signal from a power carrier while providing low forward voltage drop for improved efficiency. The battery charger employs a new control loop that

Pengfei Li; Rizwan Bashirullah

2007-01-01

292

Hysteresis in Thin-Film Rechargeable Lithium Batteries.  

National Technical Information Service (NTIS)

Discharge - charge cycling of thin-film rechargeable lithium batteries with an amorphous or nanocrystalline LiXMn2.Y04 cathode reveals evidence for a true hysteresis in the lithium insertion reaction. This is compared with an apparent hysteresis attribute...

J. B. Bates N. J. Dudney C. D. Evans F. X. Hart

1999-01-01

293

High power, rechargeable, pile type silver zinc battery  

Microsoft Academic Search

This patent describes a high rate rechargeable silver-zinc pile type battery including a plurality of bipolar electrodes which are assembled into a full scale multi-cell pile. Each of bipolar electrodes includes a positive side having a porous silver matrix attached to silver foil and a negative side having a porous zinc structure vapor deposited on silver foil. A separator including

L. R. Erisman; R. A. Marsh

1978-01-01

294

Separation composition evaluation in model rechargeable silver-zinc cells  

Microsoft Academic Search

In previous reports, the evaluation of Viskase sausage casings (SCs) in a variety of configurations for silver\\/zinc rechargeable cells has been reported. The conclusions have been that several layers of SC, while providing improved resistance to silver migration acid zinc dendrite growth compared to standard cellophane film, also impart increased internal impedance which leads to faster capacity loss in comparison

H. Lewis; S. Henderson; T. Danko

2001-01-01

295

Uncertainty in Climatology-Based Estimates of Shallow Groundwater Recharge  

Microsoft Academic Search

The groundwater recharge (GR) estimates for flow and transport projections are often evaluated as a fixed percentage of average annual precipitation. The chemical transport in variably saturated heterogeneous porous media is not linearly related to the average velocity. The objective of this study was to estimate the variability in annual, seasonal, and event-based GR at the field scale and to

A. K. Guber; Y. Pachepsky; T. J. Gish; T. J. Nicholson; R. R. Cady

2007-01-01

296

Trench infiltration for managed aquifer recharge to permeable bedrock  

USGS Publications Warehouse

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.

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

2011-01-01

297

A rechargeable non-aqueous Mg-O2 battery.  

PubMed

We propose a catalytic cycle using the iodine-dimethylsulfoxide (I2-DMSO) complex for the realization of secondary Mg-O2 batteries. We have demonstrated that the Mg-O2 battery incorporating an I2-DMSO complex electrolyte showed evidence of being rechargeable. PMID:23985777

Shiga, Tohru; Hase, Yoko; Kato, Yuichi; Inoue, Masae; Takechi, Kensuke

2013-08-29

298

Electrolytes for rechargeable lithium batteries. Research and development technical report  

SciTech Connect

Theoretical considerations predict increased stability of cyclic ethers and diethers against reductive cleavage by lithium if the ethers have 2 methyl substitution. Diethers are solvents with low viscosity which are desirable for high rate rechargeable lithium batteries. Synergistic, mixed solvent effects increase electrolyte conductance and rate capability of lithium intercalating cathodes.

Hunger, H.F.

1981-09-01

299

Climate change effects on vegetation characteristics and groundwater recharge  

Microsoft Academic Search

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

2010-01-01

300

A polymer electrolyte-based rechargeable lithium\\/oxygen battery  

Microsoft Academic Search

A novel rechargeable Li\\/Oâ battery is reported. It comprises a Li{sup +} conductive organic polymer electrolyte membrane sandwiched by a thin Li metal foil anode, and a thin carbon composite electrode on which oxygen, the electroactive cathode material, accessed from the environment, is reduced during discharge to generate electric power. It features an all solid state design in which electrode

K. M. Abraham; Z. Jiang

1996-01-01

301

Climate Change Effects on Yucca Mountain Region Groundwater Recharge  

Microsoft Academic Search

Groundwater geochemical data from 211 sampling locations in the Amargosa Desert region are analyzed to better understand the general flow system and climate-induced changes in recharge around Fortymile Wash near Yucca Mountain. Major ion groundwater chemistry was examined using the multivariate statistical methods of principal component analysis and k-means cluster analysis. These analyses showed several groundwater signatures, or potential flowpaths;

Arturo Woocay; John C. Walton

2006-01-01

302

Potential for Recharge in Agricultural Soils of the Mississippi Delta  

NASA Astrophysics Data System (ADS)

Ground water models predict that 5 percent or less of precipitation in the Mississippi Delta region recharges the heavily-used alluvial aquifer; however the presence of agricultural chemicals in ground water suggests more substantial recharge. In a preliminary assessment of the potential for aerial recharge through the agricultural soils of the Bogue Phalia basin in the Mississippi Delta, we applied a method for rapidly measuring field- saturated hydraulic conductivity (Kfs) in 26 locations in cotton and soybean fields. The technique makes use of a portable falling-head, small-diameter, single-ring infiltrometer and an analytical formula for Kfs that compensates both for falling head and for subsurface radial spreading. Soil samples were also collected at the surface and at about 6 cm depth at each location for particle size analysis. Kfs values are generally higher than anticipated and vary over more than three orders of magnitude from 1x10-2 to 5x10-6 cm/s. There is also a correlation between Kfs and mean particle size which may prove useful in generalizing recharge rates over larger areas. A 2-m ring infiltration test is planned that will include the use of tracers and subsurface instruments for measuring water content and matric potential from the near surface to about 5 m to evaluate flow and transport below the root zone.

Perkins, K. S.; Nimmo, J. R.; Coupe, R. H.; Rose, C. E.; Manning, M. A.

2007-12-01

303

Lithium-Air Battery: Study of Rechargeability and Scalability.  

National Technical Information Service (NTIS)

Lithium-air battery is anticipated as the battery with highest energy density among all existing rechargeable battery systems known now. Literature reports suggest that the theoretical energy density of Li-air battery is close to that of gasoline. Thus, i...

M. Nookala

2012-01-01

304

Rechargeable zinc air batteries market and technology overview  

Microsoft Academic Search

AER Energy Resources is an Atlanta based technology company that has developed a rechargeable zinc air battery system. The primary advantage of the AER Energy Advanced Technology Battery is that its energy density on a weight basis is three times that of nickel cadmium, nickel metal hydride and lead acid batteries, and fifty percent higher than lithium ion batteries. This

M. Schimpf

1995-01-01

305

Climate change effects on vegetation characteristics and groundwater recharge  

NASA Astrophysics Data System (ADS)

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.

(Flip) Witte, J. P. M.; (Ruud) Bartholomeus, R. P.; (Gijsbert) Cirkel, D. G.

2010-05-01

306

Understanding surface-groundwater interactions through combined physical and chemical data analysis: tracing shallow groundwater recharge in Christchurch, New Zealand  

NASA Astrophysics Data System (ADS)

Determining sustainable water resource utilization rates is an important problem faced by regulatory agencies all around the world. One of the key parameters in determining accurate water budgeting schemes is the rate of water resource replenishment, or ‘recharge’ in groundwater systems. Fundamental questions regarding groundwater recharge include: What is the source of recharge? What is the spatial distribution of recharge? What is the annual average recharge rate, from potentially disparate sources in disparate areas? Answers to these questions can be gained through combining physical and chemical hydrogeological research tools, including stable isotopic compositions. Land-use intensification, including significant increases in dairying, has placed a priority on developing water resource management practices throughout New Zealand. In Canterbury (eastern South Island, New Zealand), applications for groundwater abstraction have increased 2-fold in the past decade. Fortunately, a wealth of long-term physical hydrogeological data for Cantberbury Plains aquifers is available through the regional government. However, basic chemical data, including potential tracers such as stable isotopic compositions, are generally absent at the regional scale. Here we present the first compilation of ?18O and ?D values from individual precipitation events, local surface waters, depression springs, and groundwaters from the greater-Christchurch area. A variety of analytical methods were used in an effort to evaluate the potential use of water resource stable isotopic compositions as tracers of surface-groundwater interaction in the local hydrologic cycle. Our analysis produced several important findings: 1) Hybrid Single Particle Lagrangian Intergrated Trajectory (HYSPLIT) analysis does not yield a consistent pattern relating isotopic composition to air parcel trajectory. 2) shallow groundwater and depression spring isotopic compositions match high-altitude derived braided river waters, but not local precipitation. However, further research is needed to better constrain long-term average ?18O and ?D values for precipitation. 3) long-term trends in piezometric surface elevations reflect changes in river base flow conditions; 4) short-term fluctuations, in piezometric surface elevations, correspond with significant precipitation events. In combination, these results present a compelling case for shallow groundwater recharge by surface water channel leakage in this portion of the Canterbury Plains, demonstrating the potential application of combined physical and chemical hydrologic data analysis to informing water resource management and decision-making practices.

Blackstock, J. M.; Horton, T. W.; Zawar-Reza, P.

2010-12-01

307

Ecohydrologic process modeling of mountain block groundwater recharge.  

PubMed

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

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

2009-08-20

308

Classification of ground-water recharge potential in three parts of Santa Cruz County, California  

USGS Publications Warehouse

Ground-water recharge potential was classified in the Santa Cruz coastal area, North-central area, and Soquel-Aptos area in Santa Cruz County, Calif., for three data elements that affect recharge; slope, soils, and geology. Separate numerical maps for each element were composited into a single numerical map using a classification system that ranked the numbers into areas of good , fair, and poor recharge potential. Most of the Santa Cruz coastal area and the Norht-central area have a poor recharge potential, and much of the Soquel-Aptos area has a good to fair recharge potential. (Kosco-USGS)

Muir, K. S.; Johnson, Michael J.

1979-01-01

309

An overview of experiences of basin artificial recharge of ground water in Japan  

NASA Astrophysics Data System (ADS)

In this paper, the author reviews the present situation of basin artificial recharge of ground water (MAR: managed aquifer recharge) as of 2007 in Japan. Most of the artificial recharge of basin method is carried out using alluvial fans. The enhancing groundwater resources in the Rokugo alluvial aquifer has resulted in sustainability for the groundwater environment, especially in the distal fan. As a general judgment, the basin artificial recharge contributes to sustainable aquifer management in alluvium. As a result of this review, the basin artificial recharge will be utilized more in the future, not only in Japan, but in monsoon Asian countries as well.

Hida, Noboru

310

Transient heat and mass transfer modeling aspects of rechargeable lithium/polymer electrolyte batteries  

NASA Astrophysics Data System (ADS)

Rechargeable lithium/polymer electrolyte batteries have the potential for higher energy density than existing lithium-ion type batteries. However, lithium/polymer batteries have limited cycle life. Discharge capacity is extremely sensitive to temperature and discharge rate, and potential safety problems exist and are related to battery temperature distribution. This dissertation addresses several of these battery performance limiting issues by modeling fundamental heat and mass transfer processes that occur during lithium/polymer battery operation. A transient, three dimensional heat transfer and generation model was developed and applied to a single lithium/poly(ethylene oxide)/titanium disulfide cell. This model can be used to predict the cell temperatures for a new type of thermal battery, namely, a lithium/polymer thermal battery. Fundamental processes that occur at the lithium/polymer electrolyte interface were determined and a diffusion-limited reaction model was proposed to explain the interfacial resistance growth with time. The addition of alumina to the poly(ethylene oxide) polymer electrolyte reduces the magnitude and growth rate of the interfacial resistance mainly by serving as a diluent. The cell voltage and discharge capacity as a function of discharge rate for a room temperature rechargeable lithium/polymer electrolyte/lithium manganese oxide cell were accurately simulated by a simple diffusion-limited reaction model and by a transient, two-dimensional mass transfer and generation model. The importance of using the intrinsic lithium chemical diffusion coefficient in modeling lithium insertion cathode materials is addressed.

Fellner, Joseph Phillip

311

Process for recharging secondary batteries. [Vapor transport of S during recharging improved by maintaining temperature gradient in cathodic reaction zone  

Microsoft Academic Search

An improved process is described for recharging secondary cells or batteries of the type which in the discharged state comprise (a) an anodic reaction zone containing a molten alkali metal reactant-anode in electrical contact with an external circuit; (b) a cathodic reaction zone containing (1) cathodic reactants selected from the group consisting of (i) a single-phase composition comprising molten polysulfide

R. W. Minck; N. Weber; Y. Chang

1976-01-01

312

Rechargeable lithium batteries with solid polymer electrolytes  

Microsoft Academic Search

Scientific and technical problems connected with the realization of a practical lithium battery with a solid polymer electrolyte are reviewed. The viewpoint is that one important aim of basic scientific work should be to provide sufficient experimental data and theoretical understanding to permit computer-aided optimization of battery design, and performance. At present, this aim cannot be reached. The types of

J. W. Lorimer

1990-01-01

313

Probabilistic analysis of the effects of climate change on groundwater recharge  

NASA Astrophysics Data System (ADS)

Groundwater recharge is likely to be affected by climate change. In semiarid regions where groundwater resources are often critical, annual recharge rates are typically small and most recharge occurs episodically. Such episodic recharge is uncertain and difficult to predict. This paper analyzes the impacts of different climate predictions on diffuse episodic recharge at a low-relief semiarid rain-fed agricultural area. The analysis relies on a probabilistic approach that explicitly accounts for uncertainties in meteorological forcing and in soil and vegetation properties. An ensemble of recharge forecasts is generated from Monte Carlo simulations of a study site in the southern High Plains, United States. Soil and vegetation parameter realizations are conditioned on soil moisture and soil water chloride observations (Ng et al., 2009). A stochastic weather generator provides realizations of meteorological time series for climate alternatives from different general circulation models. For most climate alternatives, predicted changes in average recharge (spanning -75% to +35%) are larger than the corresponding changes in average precipitation (spanning -25% to +20%). This suggests that amplification of climate change impacts may occur in groundwater systems. Predictions also include varying changes in the frequency and magnitude of recharge events. The temporal distribution of precipitation change (over seasons and rain events) explains most of the variability in predictions of recharge totals and episodic occurrence. The ensemble recharge analysis presented in this study offers a systematic approach to investigating interactions between uncertainty and nonlinearities in episodic recharge.

Ng, Gene-Hua Crystal; McLaughlin, Dennis; Entekhabi, Dara; Scanlon, Bridget R.

2010-07-01

314

A New Method for Estimating Recharge to Unconfined Aquifers Using Differential River Gauging.  

PubMed

In semiarid and arid environments, leakage from rivers is a major source of recharge to underlying unconfined aquifers. Differential river gauging is widely used to estimate the recharge. However, the methods commonly applied are limited in that the temporal resolution is event-scale or longer. In this paper, a novel method is presented for quantifying both the total recharge volume for an event, and variation in recharge rate during an event from hydrographs recorded at the upstream and downstream ends of a river reach. The proposed method is applied to river hydrographs to illustrate the method steps and investigate recharge processes occurring in a sub-catchment of the Murray Darling Basin (Australia). Interestingly, although it is the large flood events which are commonly assumed to be the main source of recharge to an aquifer, our analysis revealed that the smaller flow events were more important in providing recharge. PMID:23550897

McCallum, Andrew M; Andersen, Martin S; Acworth, R Ian

2013-04-01

315

Unitized regenerative fuel cell systems  

Microsoft Academic Search

Energy storage systems with extremely high specific energy (>400 Wh\\/kg) have been designed;\\u000athat use lightweight pressure vessels to contain the gases generated by reversible (unitized);\\u000aregenerative fuel cells (URFCs).[1] URFC systems are being designed and developed for a variety;\\u000aof applications, including high altitude long endurance (HALE) solar rechargeable aircraft (SRA),;\\u000azero emission vehicles (ZEVs), hybrid energy storage\\/propulsion systems

F Mitlitsky; T M Molter; B Myers; A H Weisberg

1998-01-01

316

Hydrometeorological daily recharge assessment model (DREAM) for the Western Mountain Aquifer, Israel: Model application and effects of temporal patterns  

Microsoft Academic Search

Recharge is a critical issue for water management. Recharge assessment and the factors affecting recharge are of scientific and practical importance. The purpose of this study was to develop a daily recharge assessment model (DREAM) on the basis of a water balance principle with input from conventional and generally available precipitation and evaporation data and demonstrate the application of this

N. A. Sheffer; E. Dafny; H. Gvirtzman; S. Navon; A. Frumkin; E. Morin

2010-01-01

317

Combined estimation of specific yield and natural recharge in a semi-arid groundwater basin with irrigated agriculture  

Microsoft Academic Search

A water budget approach is developed to jointly estimate specific yield and natural recharge in an unconfined aquifer with significant seasonal water table fluctuations. Water table fluctuations are due to distinct seasonality in groundwater recharge. The separation of the hydrologic year into two (or more) extended seasons of recharge (wet season) and no-recharge (dry season) with accompanying changes in water

J. C. Maréchal; B. Dewandel; S. Ahmed; L. Galeazzi; F. K. Zaidi

2006-01-01

318

Modeling Changes Of The Smear Zone Due To Water Table Fluctuations In Fuel Leaking Transport Studies  

NASA Astrophysics Data System (ADS)

Effect of water table fluctuations on the size of gasoline fuel plume has been largely ignored in the gasoline transport modeling due to the complexity of the problem. We are attempting to analyze the discrepancies that might be produced on the size of smear zone and the concentration of fuel components when water table fluctuations are not considered in the model. Three mechanisms of interest in our model are aquifer recharge, flow through a smear zone and ground water flow in contact with the bottom of the lens. Of these, we think water table fluctuation strongly influences smear zone dissolution and plays a role in the others. The fluctuating water table can change the distribution of the fuel as two- and three-phase residual saturations are immobilized or remobilized, and the fuel saturation changes in the porous matrix. Fluctuation induced changes to the part of the smear zone that is available for leaching and volatilization create changes in the mass flux to the aquifer. Sinusoidal changes in water table elevation are incorporated directly into an analytical solution of dissolution from a static lens. Consequential changes of concentration of the fuel components in smear zones are analyzed based on the mass conservation. The mass conservation equation applied over the lens gives a simple solution for equilibrium dissolution from the fuel lens. When the fuel lens is subjected to leaching from various mechanisms, components of fuel dissolve into water in accordance with their chemical properties and abundance in fuel. The fuel concentration and water level data collected near one of the service stations in New Jersey are used in the model study. Initial analyses shown that significant discrepancies on the size of smear zone might occur when the water table fluctuations are not considered in the model.

Weaver, J.; Sun, H.

2001-05-01

319

Remote sensing of soil moisture: implications for groundwater recharge  

NASA Astrophysics Data System (ADS)

Remote sensing provides information on the land surface. Therefore, linkages must be established if these data are to be used in groundwater and recharge analyses. Keys to this process are the use of remote sensing techniques that provide information on soil moisture and water-balance models that tie these observations to the recharge. Microwave remote sensing techniques are used to map the spatial domain of surface soil moisture and to monitor its temporal dynamics, information that cannot be measured using other techniques. The physical basis of this approach is presented with examples of how microwave remote sensing is utilized in groundwater recharge and related studies. Résumé. La télédétection fournit des informations sur la surface du sol. C'est pourquoi des liens doivent être établis lorsque ces données sont utilisées dans l'étude des eaux souterraines et de leur recharge. Les clés de cette démarche sont l'utilisation des techniques de télédétection qui informent sur l'humidité du sol et les modèles de bilan hydrologique qui associent ces observations à la recharge. Les techniques de télédétection dans le domaine des micro-ondes sont mises en œuvre pour cartographier l'humidité du sol en surface dans l'espace et pour suivre sa dynamique dans le temps, informations qui ne peuvent pas être obtenues par d'autres techniques. La base physique de cette approche est présentée avec des exemples d'utilisation de la télédétection micro-onde pour la recharge de nappes et dans les études associées. Resumen. La teledetección proporciona información de la superficie terrestre. Por ello, se debe establecer vínculos si se pretende utilizar dichos datos para análisis de aguas subterráneas y recarga. Son factores clave en este proceso el uso de técnicas de teledetección para recoger información sobre la humedad del suelo y los modelos de balance de agua que ligan estas observaciones con la recarga. Las técnicas de teledetección por microondas se emplean con el fin de cartografiar el dominio espacial de la humedad superficial del suelo y controlar su dinámica temporal, cosa que no se puede lograr con otros medios. Se presenta el fundamento físico de este enfoque mediante ejemplos de cómo la teledetección por microondas es aplicada en estudios de recarga y trabajos relacionados.

Jackson, Thomas

2002-01-01

320

Natural Recharge Estimation and Uncertainty Analysis of an Adjudicated Groundwater Basin using a Regional-Scale Groundwater Flow and Subsidence Model  

NASA Astrophysics Data System (ADS)

The Superior Court of California recently ruled that the Antelope Valley groundwater basin is in overdraft-groundwater extractions are in excess of the "safe yield" of the groundwater basin. As defined by the Court, "safe yield is the amount of annual extractions of water from an aquifer over time equal to the amount of water needed to recharge the groundwater aquifer and maintain it in equilibrium, plus any temporary surplus." Natural recharge is an important component of total groundwater recharge in Antelope Valley; however, the exact quantity and distribution of natural recharge is uncertain with estimates ranging from 30,000 to 160,000 acre-feet per year. Weighing the evidence presented by experts, the Court determined that the "safe yield" of the adjudicated area of the basin was 110,000 acre-feet per year. Knowledge of the quantity and distribution of natural recharge is needed to evaluate whether the Court-defined "safe yield" estimate for the basin will minimize additional storage depletion, and related land subsidence, resulting from continued groundwater extraction. The objective of this study is to systematically address the uncertainty in estimates of natural recharge and related aquifer parameters using a groundwater-flow and land-subsidence model with observational data and expert knowledge. Observational data include measured water levels, land-surface deformation, and estimates of transmissivity throughout the basin. An example of expert knowledge is the distribution of artesian conditions for pre-development times. Even though a great wealth of data is available, the problem of non-uniqueness remains present throughout the calibration process. Regularization is used to systematically identify combinations of parameters that can be uniquely estimated as well as to impose expert knowledge onto the parameter identification process. Once the model was calibrated with a reasonable parameter set, the parameter null-space was identified (i.e., the combinations of parameters that cannot be estimated given the available observation data). The majority of the parameter uncertainty is represented by the parameter null-space. Uncertainty in the average annual recharge was evaluated using the null-space Monte-Carlo method. Preliminary results indicate that the total natural recharge ranges between 30,000 and 50,000 acre-ft/yr, which is significantly lower than the Court-determined "safe yield".

Siade, A. J.; Nishikawa, T.; Martin, P.

2011-12-01

321

Alternative fuels for transportation  

Microsoft Academic Search

The alternatives to the oil based fuels for transportation are considered and analysed. These are the synthetic fuels, made from coal, the liquid petroleum gases of propane and butane, compressed natural gas and methanol. The problems associated with the use of electric vehicles are discussed; the main problem being that of range.The possible use of hydrogen as a fuel is

G. G. Lucas; W. L. Richards

1982-01-01

322

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

USGS Publications Warehouse

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.

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

2007-01-01

323

Characterizing Field Biodegradation of N-nitrosodimethylamine (NDMA) in Groundwater with Active Reclaimed Water Recharge  

NASA Astrophysics Data System (ADS)

N-Nitrosodimethylamine (NDMA) is an emerging contaminant in groundwater, because of its aqueous miscibility, exceptional animal toxicity, and human carcinogenicity. NDMA detections in groundwater have been tracked to either decomposition of unsymmetrical dimethylhydrazine (UDMH) used in rocket fuel facilities or chlorine disinfection in wastewater reclamation plants. Laboratory experiments on both unsaturated and saturated soil samples have demonstrated that NDMA can be biodegraded by microbial activity, under both aerobic and anaerobic conditions. However, very limited direct evidence for its biodegradation has been found from the field in saturated groundwater. Our research aimed to evaluate photolysis and biodegradation of NDMA occurring along the full travel path - from wastewater reclamation plant effluent, through rivers and spreading grounds, to groundwater. For this evaluation, we established an extensive monitoring network to characterize NDMA concentrations at effluent discharge points, surface water stations, and groundwater monitoring and production wells, during the operation of the Montebello Forebay Groundwater Recharge facilities in Los Angeles County, California. Field monitoring for NDMA has been conducted for more than six years, including 32 months of relatively lower NDMA concentrations in effluent, 43 months of elevated NDMA effluent concentrations, and 7 months with significantly reduced NDMA effluent concentrations. The NDMA effluent concentration increase and significant concentration decrease were caused by changes in treatment processes. The NDMA sampling data imply that significant biodegradation occurred in groundwater, accounting for a 90% mass reduction of NDMA over the six-year monitoring period. In addition, the occurrence of a discrete well monitored effluent release during the study period allowed critical analysis of the fate of NDMA in a well- characterized, localized groundwater flow subsystem. The data indicate that 80% of the recharged NDMA mass was biodegraded in groundwater with the remaining mass pumped out by extraction wells. To reproduce the observation data, a groundwater flow and transport model was developed and calibrated against groundwater elevation and NDMA concentration data. The calibrated half-life of NDMA in groundwater is 69 days, which is consistent with the values obtained through laboratory incubation using soil samples from the Montebello Forebay Spreading Grounds. Given the photolysis of NDMA in surface water and biodegradation in groundwater observed during this study, reclaimed wastewater with limited NDMA concentrations can be safely used for groundwater recharge under the study area conditions.

McCraven, S.; Zhou, Q.; Garcia, J.; Gasca, M.; Johnson, T.

2007-12-01

324

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

NASA Astrophysics Data System (ADS)

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.

Sammarco, John J.

325

Novel electrolyte chemistries for Mg-Ni rechargeable batteries.  

SciTech Connect

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.

Garcia-Diaz, Brenda (Savannah River National Laboratory); Kane, Marie; Au, Ming (Savannah River National Laboratory)

2010-10-01

326

Prussian blue containing Nafion composite film as rechargeable battery  

SciTech Connect

A solid-state thin film rechargeable battery has been prepared using a novel efficient technique of ''surface complexation method'' by which a thin layer of Prussian blue (PB) can be overlaid on a solid polymer electrolyte of Nafion (NF) as matrix. An electrochemical cell made of the composite PB-Nf film sandwiched with supporting electrodes was examined on i-V curves in solid state and for characteristics as a rechargeable battery. The resulting PB-Nf battery showed good durability in repetitive cycles of charging and discharging and gave the following results: open-circuit voltage of the unit cell per 160 ..mu..m 0.68V, short-circuit current 0.2-2 mA/cm/sup 2/ depending upon the water content of the Nf matrix, and an energy density of about 50 Wh/kg.

Honda, K.; Hayashi, H.

1987-06-01

327

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

SciTech Connect

The author reports on 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.

Sammarco, J.J.

1989-01-01

328

A polymer electrolyte-based rechargeable lithium/oxygen battery  

SciTech Connect

A novel rechargeable Li/O{sub 2} battery is reported. It comprises a Li{sup +} conductive organic polymer electrolyte membrane sandwiched by a thin Li metal foil anode, and a thin carbon composite electrode on which oxygen, the electroactive cathode material, accessed from the environment, is reduced during discharge to generate electric power. It features an all solid state design in which electrode and electrolyte layers are laminated to form a 200 to 300 {micro}m thick battery cell. The overall cell reaction during discharge appears to be 2Li + O{sub 2} {yields} Li{sub 2}O{sub 2}. It has an open-circuit voltage of about 3 V, and a load voltage that spans between 2 and 2.8 V depending upon the load resistance. The cell can be recharged with good coulombic efficiency using a cobalt phthalocyanine catalyzed carbon electrode.

Abraham, K.M.; Jiang, Z. [EIC Labs., Inc., Norwood, MA (United States)

1996-01-01

329

Water quality management of aquifer recharge using advanced tools.  

PubMed

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

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

2011-01-01

330

Using Managed Aquifer Recharge to Remove Contaminants from Water  

NASA Astrophysics Data System (ADS)

Managed aquifer recharge (MAR) is a mechanism that has strong potential to aid in the capture and reuse of water where there is a need for additional resources. It has been employed around the world to improve water resources for local communities and has also been demonstrated to have the potential to improve the quality of recharged water. Information is still lacking, however, on many of the processes impacting the fate and behavior of contaminants such as microbial pathogens, trace organics, and nutrients on anything larger than a local scale. Government regulators, conservation groups, and local communities remain concerned about the applicability of transferring research findings on MAR from one region and nation to another. This paper will examine the current knowledge base and research relating to the fate of pathogens, trace organics, and nutrients during MAR, and discuss the applicability to transfer these findings between regions.

Toze, Imon

331

Episodic recharge and climate change in the Murray-Darling Basin, Australia  

NASA Astrophysics Data System (ADS)

In semi-arid areas, episodic recharge can form a significant part of overall recharge, dependant upon infrequent rainfall events. With climate change projections suggesting changes in future rainfall magnitude and intensity, groundwater recharge in semi-arid areas is likely to be affected disproportionately by climate change. This study sought to investigate projected changes in episodic recharge in arid areas of the Murray-Darling Basin, Australia, using three global warming scenarios from 15 different global climate models (GCMs) for a 2030 climate. Two metrics were used to investigate episodic recharge: at the annual scale the coefficient of variation was used, and at the daily scale the proportion of recharge in the highest 1% of daily recharge. The metrics were proportional to each other but were inconclusive as to whether episodic recharge was to increase or decrease in this environment; this is not a surprising result considering the spread in recharge projections from the 45 scenarios. The results showed that the change in the low probability of exceedance rainfall events was a better predictor of the change in total recharge than the change in total rainfall, which has implications for the selection of GCMs used in impact studies and the way GCM results are downscaled.

Crosbie, Russell S.; McCallum, James L.; Walker, Glen R.; Chiew, Francis H. S.

2012-03-01

332

Scale effects of hydrostratigraphy and recharge zonation on base flow.  

PubMed

Uncertainty regarding spatial variations of model parameters often results in the simplifying assumption that parameters are spatially uniform. However, spatial variability may be important in resource assessment and model calibration. In this paper, a methodology is presented for estimating a critical basin size, above which base flows appear to be relatively less sensitive to the spatial distribution of recharge and hydraulic conductivity, and below which base flows are relatively more sensitive to this spatial variability. Application of the method is illustrated for a watershed that exhibits distinct infiltration patterns and hydrostratigraphic layering. A ground water flow model (MODFLOW) and a parameter estimation code (UCODE) were used to evaluate the influence of recharge zonation and hydrostratigraphic layering on base flow distribution. Optimization after removing spatial recharge variability from the calibrated model altered base flow simulations up to 53% in watersheds smaller than 40 km(2). Merging six hydrostratigraphic units into one unit with average properties increased base flow residuals up to 83% in basins smaller than 50 km(2). Base flow residuals changed <5% in watersheds larger than 40 and 50 km(2) when recharge and hydrostratigraphy were simplified, respectively; thus, the critical basin size for the example area is approximately 40 to 50 km(2). Once identified for an area, a critical basin size could be used to guide the scale of future investigations. By ensuring that parameter discretization needed to capture base flow distribution is commensurate with the scope of the investigation, uncertainty caused by overextending uniform parameterization or by estimating extra parameter values is reduced. PMID:16681517

Juckem, Paul F; Hunt, Randall J; Anderson, Mary P

333

Templated Nanocarbon Black Nanocomposite Electrodes for Rechargeable Lithium Batteries  

Microsoft Academic Search

In this work, the fabrication of high energy density electrode materials for solid-state rechargeable batteries via block copolymer templating schemes was investigated. Atom transfer radical polymerization was used to synthesize the copolymer template poly((oligooxyethylene) methacrylate)-block-poly(butyl methacrylate), POEM-b-PBMA. Continuous, nanoscale phases of vanadium oxide were subsequently grown within the POEM domains of the microphase-separating block copolymer using sol-gel synthesis from a

Ozge Akbulut; Elsa A. Olivetti; Donald R. Sadoway; Anne M. Mayes

2006-01-01

334

Alkaline composite film as a separator for rechargeable lithium batteries  

Microsoft Academic Search

We report a new type of separator film for application in rechargeable lithium and lithium-ion batteries. The films are made\\u000a of mainly alkaline calcium carbonate (CaCO3) and a small amount of polymer binder. Owing to porosity and capillarity, the composite films show excellent wettability\\u000a with non-aqueous liquid electrolytes. Typically, the composite films composed of CaCO3 and Teflon and wetted with

S. S. Zhang; K. Xu; T. R. Jow

2003-01-01

335

Virus fate and transport during artificial recharge with recycled water  

Microsoft Academic Search

A field-scale experiment was conducted at a research site using bacterial viruses (bacteriophage) MS2 and PRD1 as surrogates for human viruses, bromide as a conservative tracer, and tertiary-treated municipal wastewater (recycled water) to investigate the fate and transport of viruses during artificial recharge. Observed virus concentrations were fitted using a mathematical model that simulates virus transport in one-dimensional, homogeneous, water-saturated

Robert Anders; C. V. Chrysikopoulos

2005-01-01

336

Estimating recharge at Yucca Mountain, Nevada, USA: comparison of methods  

Microsoft Academic Search

.   Obtaining values of net infiltration, groundwater travel time, and recharge is necessary at the Yucca Mountain site, Nevada,\\u000a USA, in order to evaluate the expected performance of a potential repository as a containment system for high-level radioactive\\u000a waste. However, the geologic complexities of this site, its low precipitation and net infiltration, with numerous mechanisms\\u000a operating simultaneously to move water

Alan L. Flint; Lorraine E. Flint; Edward M. Kwicklis; June T. Fabryka-Martin; Gudmundur S. Bodvarsson

2002-01-01

337

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

USGS Publications Warehouse

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.

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

2002-01-01

338

Fluoride content and recharge ability of five glassionomer dental materials  

Microsoft Academic Search

BACKGROUND: The relationship between fluoride content and fluoride release for glass-ionomer cements is not well understood. The aim of this laboratory study was: to determine the fluoride concentrations at the surfaces of glass-ionomer materials with respect to different storage media and different pH environments; to examine the recharge ability of the materials after NaF immersion; and to assess the morphological

Dejan Lj Markovic; Bojan B Petrovic; Tamara O Peric

2008-01-01

339

Spatial and temporal infiltration dynamics during managed aquifer recharge.  

PubMed

Natural groundwater recharge is inherently difficult to quantify and predict, largely because it comprises a series of processes that are spatially distributed and temporally variable. Infiltration ponds used for managed aquifer recharge (MAR) provide an opportunity to quantify recharge processes across multiple scales under semi-controlled conditions. We instrumented a 3-ha MAR infiltration pond to measure and compare infiltration patterns determined using whole-pond and point-specific methods. Whole-pond infiltration was determined by closing a transient water budget (accounting for inputs, outputs, and changes in storage), whereas point-specific infiltration rates were determined using heat as a tracer and time series analysis at eight locations in the base of the pond. Whole-pond infiltration, normalized for wetted area, rose rapidly to more than 1.0 m/d at the start of MAR operations (increasing as pond stage rose), was sustained at high rates for the next 40 d, and then decreased to less than 0.1 m/d by the end of the recharge season. Point-specific infiltration rates indicated high spatial and temporal variability, with the mean of measured values generally being lower than rates indicated by whole-pond calculations. Colocated measurements of head gradients within saturated soils below the pond were combined with infiltration rates to calculate soil hydraulic conductivity. Observations indicate a brief period of increasing saturated hydraulic conductivity, followed by a decrease of one to two orders of magnitude during the next 50 to 75 d. Locations indicating the most rapid infiltration shifted laterally during MAR operation, and we suggest that infiltration may function as a "variable source area" processes, conceptually similar to catchment runoff. PMID:22050208

Racz, Andrew J; Fisher, Andrew T; Schmidt, Calla M; Lockwood, Brian S; Los Huertos, Marc

2011-11-03

340

Hysteresis in Thin-Film Rechargeable Lithium Batteries  

SciTech Connect

Discharge - charge cycling of thin-film rechargeable lithium batteries with an amorphous or nanocrystalline LiXMn2.Y04 cathode reveals evidence for a true hysteresis in the lithium insertion reaction. This is compared with an apparent hysteresis attributed to a kinetically hindered phase transition near 3 V for batteries with either a crystalline or a nanocrystalline LiJ@Yo4 cathode.

Bates, J.B.; Dudney, N.J.; Evans, C.D.; Hart, F.X.

1999-04-25

341

Recharge estimate for the Hanford Site 200 Areas plateau  

Microsoft Academic Search

An evaluation was made to assess the magnitude of recharge from natural precipitation on the Hanford Site 200 Areas plateau. Two sources of data were used in the evaluation moisture accumulation in a 200 East Area closed-bottom lysimeter for 13 yr, and distribution of ¹³⁷Cs in a solid-waste trench in which contaminated soil had been buried for 10 yr. Cesium-137

R. C. Routson; M. R. Fuchs; W. A. Jordan

1988-01-01

342

Equivalent circuits for switched-capacitor networks including recharging devices  

Microsoft Academic Search

Equivalent circuits for switched-capacitor (SC) networks including recharging devices are derived. Parasitic effects, like stray capacitances and nonideal op amps, are taken into account. As a result, the equivalent time-invariant network is split up into a frequency dependent impedance network and a purely (negative) resistive network which corresponds directly to the capacitor network of the SC-filter and allows for the

JOSEF A. NOSSEK; HANS WEINRICHTER

1980-01-01

343

Managed aquifer recharge: rediscovering nature as a leading edge technology.  

PubMed

Use of Managed Aquifer Recharge (MAR) has rapidly increased in Australia, USA, and Europe in recent years as an efficient means of recycling stormwater or treated sewage effluent for non-potable and indirect potable reuse in urban and rural areas. Yet aquifers have been relied on knowingly for water storage and unwittingly for water treatment for millennia. Hence if 'leading edge' is defined as 'the foremost part of a trend; a vanguard', it would be misleading to claim managed aquifer recharge as a leading edge technology. However it has taken a significant investment in scientific research in recent years to demonstrate the effectiveness of aquifers as sustainable treatment systems to enable managed aquifer recharge to be recognised along side engineered treatment systems in water recycling. It is a 'cross-over' technology that is applicable to water and wastewater treatment and makes use of passive low energy processes to spectacularly reduce the energy requirements for water supply. It is robust within limits, has low cost, is suitable from village to city scale supplies, and offers as yet almost untapped opportunities for producing safe drinking water supplies where they do not yet exist. It will have an increasingly valued role in securing water supplies to sustain cities affected by climate change and population growth. However it is not a universal panacea and relies on the presence of suitable aquifers and sources of water together with effective governance to ensure human health and environment protection and water resources planning and management. This paper describes managed aquifer recharge, illustrates its use in Australia, outlining economics, guidelines and policies, and presents some of the knowledge about aquifer treatment processes that are revealing the latent value of aquifers as urban water infrastructure and provide a driver to improving our understanding of urban hydrogeology. PMID:21076220

Dillon, P; Toze, S; Page, D; Vanderzalm, J; Bekele, E; Sidhu, J; Rinck-Pfeiffer, S

2010-01-01

344

Changes in vegetation diversity caused by artificial recharge  

USGS Publications Warehouse

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.

van, Hylckama, T. E. A.

1979-01-01

345

Overcharge protection for rechargeable lithium polymer electrolyte batteries  

Microsoft Academic Search

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(SOâCFâ)â\\/Li{sub 2+x}MnâOâ cells under normal and severe overcharging conditions. In addition

Thomas J. Richardson; P. N. Jr. Ross

1996-01-01

346

Polymer Considerations in Rechargeable Lithium Ion Plastic Batteries  

Microsoft Academic Search

A series of polymers have been investigated in order to determine their suitability as ionically conductive binders of the active electrode materials and as hybrid electrolyte matrices in plastic lithium ion rechargeable batteries. Hybrid electrolyte films used in this study have been prepared by solvent casting using a 1:1 w\\/w mixture of the matrix polymer with 1 M LiPF6 in

Antoni S. Gozdz; Jean-Marie Tarascon; Caroline N. Schmutz; Paul Warren; O. S. Gebizlioglu; F. Shokoohi

1995-01-01

347

Solid polymer electrolytes for rechargeable batteries. Final report  

Microsoft Academic Search

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

S. C. Narang; S. C. Ventura

1992-01-01

348

Computer simulations of the impedance response of lithium rechargeable batteries  

Microsoft Academic Search

A mathematical model is developed to simulate the impedance response of a wide range of lithium rechargeable battery systems. The mathematical model is a macroscopic model of a full-cell sandwich utilizing porous electrode theory to treat the electrode region and concentrated solution theory for transport processes in solution. Insertion processes are described with charge-transfer kinetic expressions and solid-phase diffusion of

Marc Doyle; Jeremy P. Meyers; John Newman

2000-01-01

349

Natural groundwater recharge and water balance at the Hanford Site  

SciTech Connect

The purpose of this report is to present water-balance data collected in 1988 and 1989 from the 300 Area Buried Waste Test Facility and Grass Site, and the 200 East Area closed-bottom lysimeter. This report is an annual update of previous recharge status reports by Gee, Rockhold, and Downs, and Gee. Data from several other lysimeter sites are included for comparison. 43 refs., 28 figs., 7 tabs.

Rockhold, M.L.; Fayer, M.J.; Gee, G.W.; Kanyid, M.J.

1990-01-01

350

Evaluation of Recharge Potential at Crater U5a (WISHBONE)  

SciTech Connect

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.

Richard H. French; Samuel L. Hokett

1998-11-01

351

Rechargeable zinc air batteries market and technology overview  

Microsoft Academic Search

AER Energy Resources is a US-based technology company that has developed a rechargeable zinc-air battery system. The advantage of the AER Energy Technology Battery is that it's energy density on a weight basis is three times that of nickel-cadmium, nickel metal hydride and lead-acid batteries, and almost twice that of currently available lithium-ion batteries. This new battery technology can enable

M. Schimpf

1993-01-01

352

Modelling the groundwater recharge of an urban area in Germany  

NASA Astrophysics Data System (ADS)

Groundwater recharge is an important part of the natural water cycle. This cycle is disturbed particularly in urban areas. Sealing negatively influences the hydrological and mechanical soil properties. The continued sealing of soils, mainly caused by urbanisation, will continue to reduce the infiltration of water to groundwater and increase the surface run-off. Furthermore, recent and future climate changes strongly affect the available water resources. Those changes in water availability interfere with i.e., the cultivation of land, forest management, water supply, waste water disposal and urban infrastructure. Those issues are studied in the BMBF-supported joint research project REGKLAM that deals with climate change adaptation options in the model region Dresden. This work aims at simulating the groundwater recharge for the status quo and regionalised climate change scenarios and thus will deliver a central component to other parts of the REGKLAM project. Modelling is done using the two-dimensional hydrological model BOWAM. Current groundwater recharge models miss not only a high resolution, but also a realistic description of soil properties. Thus, it was necessary to develop a differentiated classification of soil and land use data. At present, we focus on the Quaternary aquifer of the region of Dresden, as there have been already conducted several studies that may serve as a reference for our more detailed and actual results.

Tesch, Sabine; Dunger, Volkmar; Matschullat, Jörg

2010-05-01

353

Recharge of aquifers by flood events in an arid region  

NASA Astrophysics Data System (ADS)

The process of aquifer recharge by flood events in an arid region was investigated as applied to the Hazeva Formation (the Karkom graben, the Wadi Paran watershed, Israel). The hydrological model was established as a complex system, with due regard for groundwater and transmission losses of surface runoff. It was based on a previously outlined hydrogeological model of the Karkom graben and a model of transmission losses in arid watercourses under conditions of data deficiency. Proceeding from calculation of groundwater balances, the contribution of surface runoff as a decisive balance component was confirmed. The main characteristics of aquifer regimes, such as changes in storage volume and groundwater level, as well as lateral flow, were all found to be dependent upon the net extraction rate, i.e. pumpage discounting replenishment by flood events. Analysis and physical interpretation of model parameters enabled assessment of the influence of groundwater extraction on aquifer recharge. This became apparent as increasing absorption capacity and recharge availability of the aquifer as a result of the groundwater abstraction.

Shentsis, Isabella; Rosenthal, Eliyahu

2003-03-01

354

Movement of water infiltrated from a recharge basin to wells.  

PubMed

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

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

2011-07-08

355

RELAP5/MOD3.2 Analysis of INSC Standard Problem INSCSP-R7: Void Fraction Distribution over RBMK Fuel Channel Height for Experiments Performed in the ENTEK BM Test Facility.  

National Technical Information Service (NTIS)

The RELAP5/MOD3.2 computer program has been used to analyze a series of tests investigating void fraction distribution over height in RBMK fuel channels performed in Facility BM at the ENTEK. This is RBMK Standard Problem 7 in Joint Project 6, which is th...

P. L. Garner

2002-01-01

356

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

NASA Astrophysics Data System (ADS)

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.

1990-01-01

357

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

SciTech Connect

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.

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

1990-01-01

358

Ponds and Rice Fields: The Hydrology and Chemistry of Aquifer Recharge in Bangladesh  

NASA Astrophysics Data System (ADS)

The shallow aquifer in Bangladesh, which provides drinking water for millions and irrigation water for innumerable rice fields, is severely contaminated with naturally occurring arsenic. Water balance calculations show that surface ponds and irrigated rice fields are the primary sources of recharge to this contaminated aquifer. Recharge from an individual rice field is both temporally and spatially heterogeneous, whereas flow from a pond is more constant and uniform through the pond sediments. Rice field recharge is focused through bunds (the berms surrounding the field), and depends on irrigation intervals. Field flow patterns are controlled by cracks and the development of an unsaturated zone. The water chemistry of these two recharge sources is distinctly different. Compared to the rice fields, ponds contribute recharge with a higher organic carbon load and increased concentrations of solutes associated with anoxic microbial respiration. The differences in the recharge behavior and solute loads of these two sources may explain the spatial patterns of groundwater chemistry that control arsenic concentrations.

Neumann, R. B.; Harvey, C. F.

2007-12-01

359

Estimating recharge at Yucca Mountain, Nevada, USA: comparison of methods  

NASA Astrophysics Data System (ADS)

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. Résumé. Les valeurs d'infiltration nette, de temps de parcours de l'eau souterraine et de la recharge sont nécessaires sur le site de Yucca Mountain, Nevada, USA, pour évaluer les capacités d'un site de stockage potentiel pour le confinement de déchets hautement radioactifs. Cependant, la complexité géologique du site, les faibles valeurs de précipitation et d'infiltration nette, associées à de nombreux mécanismes agissant simultanément pour faire se déplacer l'eau dans le système, posent de nombreux problèmes pour estimer la distribution spatiale de la recharge. Un ensemble de méthodes adaptées aux environnements arides a été mis en œuvre, comprenant les techniques de bilan hydrologique, des calculs s'appuyant sur la loi de Darcy en milieu non saturé, une méthode de physique des sols appliquée aux données de teneur en eau par mesure neutronique, une modélisation inverse des profils thermiques en forage portant sur l'épaisse zone non saturée, le bilan de masse des chlorures, les radionucléides atmosphériques et des approches empiriques. Ces méthodes indiquent que les taux d'infiltration au voisinage de la surface à Yucca Mountain sont très variables dans le temps et dans l'espace, avec des valeurs locales, ponctuelles, comprises entre 0 et plusieurs centaines de mm/an. Les valeurs d'infiltration nette distribuées dans l'espace sont en moyenne de 5 mm/an, les plus fortes approchant 20 mm/an. Ces résultats ont été introduits dans un modèle à l'échelle du site qui a été calibré au moyen de ces jeux de données, reflétant les processus d'infiltration agissant à des échelles de temps et d'espace à forte variabilité. L'étude par modélisation prédit une recharge fortement non uniforme de la nappe, dont la distribution est significativement différente de l'organisation de l'infiltration non uniforme en surface. Resumen. Se necesitan conocer los valores de infiltración neta, el tiempo de tránsito de las aguas subterráneas y la recarga en el emplazamiento de Yucca Mountain, Nevada, USA, con el fin de evaluar el comportamiento esperado de un repositorio potencial como sistema de contención de residuos de alta radioactividad. Sin embargo, la complejidad geológica del lugar y los pequeños valores de precipitación e infiltración neta, junto con los numerosos mecanismos que operan simultáneamente en relació

Flint, Alan; Flint, Lorraine; Kwicklis, Edward; Fabryka-Martin, June; Bodvarsson, Gudmundur

2002-01-01

360

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

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

Kelly, Brian P.

2011-01-01

361

POD-based Monte Carlo approach for the solution of regional scale groundwater flow driven by randomly distributed recharge  

NASA Astrophysics Data System (ADS)

We present a methodology conducive to the application of a Galerkin model order reduction technique, Proper Orthogonal Decomposition (POD), to solve a groundwater flow problem driven by spatially distributed stochastic forcing terms. Typical applications of POD to reducing time-dependent deterministic partial differential equations (PDEs) involve solving the governing PDE at some observation times (termed snapshots), which are then used in the order reduction of the problem. Here, the application of POD to solve the stochastic flow problem relies on selecting the snapshots in the probability space of the random quantity of interest. This allows casting a standard Monte Carlo (MC) solution of the groundwater flow field into a Reduced Order Monte Carlo (ROMC) framework. We explore the robustness of the ROMC methodology by way of a set of numerical examples involving two-dimensional steady-state groundwater flow taking place within an aquifer of uniform hydraulic properties and subject to a randomly distributed recharge. We analyze the impact of (i) the number of snapshots selected from the hydraulic heads probability space, (ii) the associated number of principal components, and (iii) the key geostatistical parameters describing the heterogeneity of the distributed recharge on the performance of the method. We find that our ROMC scheme can improve significantly the computational efficiency of a standard MC framework while keeping the same degree of accuracy in providing the leading statistical moments (i.e. mean and covariance) as well as the sample probability density of the state variable of interest.

Pasetto, Damiano; Guadagnini, Alberto; Putti, Mario

2011-11-01

362

Multiple-methods investigation of recharge at a humid-region fractured rock site, Pennsylvania, USA  

Microsoft Academic Search

Lysimeter-percolate and well-hydrograph analyses were combined to evaluate recharge for the Masser Recharge Site (central\\u000a Pennsylvania, USA). In humid regions, aquifer recharge through an unconfined low-porosity fractured-rock aquifer can cause\\u000a large magnitude water-table fluctuations over short time scales. The unsaturated hydraulic characteristics of the subsurface\\u000a porous media control the magnitude and timing of these fluctuations. Data from multiple sets of

Christopher S. Heppner; John R. Nimmo; Gordon J. Folmar; William J. Gburek; Dennis W. Risser

2007-01-01

363

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

SciTech Connect

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.

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

2009-09-28

364

Estimation of groundwater recharge using the soil moisture budget method and the base-flow model  

Microsoft Academic Search

Estimation of groundwater recharge is extremely important for proper management of groundwater systems. Many different approaches\\u000a exist for estimating recharge. The main purpose of this paper is to apply a water balance concept with two methods to estimate\\u000a the groundwater recharge in the Ching-Shui watershed, Taiwan. First, a soil moisture budget method is established to estimate\\u000a the infiltration, runoff, evapotranspiration,

Cheng-Haw Lee; Hsin-Fu Yeh; Jin-Fa Chen

2008-01-01

365

Climatic controls on diffuse groundwater recharge in semiarid environments of the southwestern United States  

Microsoft Academic Search

Although there is no diffuse groundwater recharge at many semiarid sites, evidence for diffuse recharge exists at some locations where mean annual precipitation $\\\\overline{P}$ is much less than mean annual potential evapotranspiration $\\\\overline{PET}$, particularly where soils are coarse and rainfall variable is substantial. We investigate the climatic controls on diffuse recharge using a one-dimensional, variably saturated flow model. The model

Eric E. Small

2005-01-01

366

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

SciTech Connect

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.

Savard, C.S.

1998-10-01

367

Hydrological functions of sinkholes and characteristics of point recharge in groundwater basins  

NASA Astrophysics Data System (ADS)

Karstic limestone aquifers are hydrologically and hydrochemically extremely heterogeneous and point source recharge via sinkholes and fissures is a common feature. We studied three groundwater systems in karstic settings dominated by point source recharge in order to assess the relative contributions to total recharge from point sources using chloride and ?18O relations. Preferential groundwater flows were observed through an inter-connected network of highly conductive zones with groundwater mixing along flow paths. Measurements of salinity and chloride indicated that fresh water pockets exist at point recharge locations. A measurable fresh water plume develops only when a large quantity of surface water enters the aquifer as a point recharge source. The difference in chloride concentrations in diffuse and point recharge zones decreases as aquifer saturated thickness increases and the plumes become diluted through mixing. The chloride concentration in point recharge fluxes crossing the watertable plane can remain at or near surface runoff chloride concentrations, rather than in equilibrium with groundwater chloride. In such circumstances the conventional chloride mass balance method that assumes equilibrium of recharge water chloride with groundwater requires modification to include both point and diffuse recharge mechanisms.

Somaratne, N.; Smettem, K.; Lawson, J.; Nguyen, K.; Frizenschaf, J.

2013-09-01

368

A numerical analysis on the applicability of the water level fluctuation method for quantifying groundwater recharge  

NASA Astrophysics Data System (ADS)

The water table fluctuation(WTF) method is a conventional method for quantifying groundwater recharge by multiplying the specific yield to the water level rise. Based on the van Genuchten model, an analytical relationship between groundwater recharge and the water level rise is derived. The equation is used to analyze the effects of the depth to water level and the soil properties on the recharge estimate using the WTF method. The results show that the WTF method is reliable when applied to the aquifers of the fluvial sand provided the water table is below 1m depth. However, if it is applied to the silt loam having the water table depth ranging 4~10m, the recharge is overestimated by 30~80%, and the error increases drastically as the water table is getting shallower. A 2-D unconfined flow model with a time series of the recharge rate is developed. It is used for elucidating the errors of the WTF method, which is implicitly based on the tank model where the horizontal flow in the saturated zone is ignored. Simulations show that the recharge estimated by the WTF method is underestimated for the observation well near the discharge boundary. This is due to the fact that the hydraulic stress resulting from the recharge is rapidly dissipating by the horizontal flow near the discharge boundary. Simulations also reveal that the recharge is significantly underestimated with increase in the hydraulic conductivity and the recharge duration, and decrease in the specific yield.

Koo, M.; Lee, D.

2002-12-01

369

Recharge in Karst Shrublands of Central Texas: Monitoring Drip Rates in Shallow Caves  

NASA Astrophysics Data System (ADS)

The exceedingly complex subsurface hydrology of karst landscapes presents formidable challenges to understanding recharge rates and the relationships between rainfall and recharge. In this study, we have established a network of drip collectors and monitoring stations in shallow caves in the Edwards Plateau to better understand the dynamics of recharge and eventually for determining the effect of woody plants on recharge rates. Understanding recharge rates has direct relevance for management of the Edwards Aquifer, which serves as the main source of fresh water for the city of San Antonio and surrounding communities, As population around San Antonio continues to grow so does the demand for water, in turn, a need to address the supply exists. We have instrumented two caves that lie within the Camp Bullis Training Facility north of San Antonio, Texas. Data collected at each site record precipitation on the surface and measure recharge inside the caves. Monitoring of natural rainfall events at these sites began in October 2004. To date, all monitoring and data collection has occurred with the juniper canopy in place. Results have shown that cave recharge is influenced by 1) rainfall intensity and duration, 2) antecedent soil moisture condition, 3) depth of soil, and 4) surface geology. We plan to remove the tree canopy in the summer of 2008 and continue monitoring cave recharge in response to natural and re-created rainfall events. Comparing data collected with and without juniper cover in place will allow us to determine if recharge may be increased by reducing tree cover.

Bazan, R. A.; Wilcox, B. P.; Munster, C. L.; Owens, K.; Shade, B.

2007-12-01

370

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

USGS Publications Warehouse

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.

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

1979-01-01

371

Artificial recharge through a thick, heterogeneous unsaturated zone.  

PubMed

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

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

2008-01-09

372

Experimental assessment of energy-management strategies in fuel-cell propulsion systems  

Microsoft Academic Search

The limitations of electric vehicles equipped with electrochemical batteries justify strong research interest for new solutions, based on hydrogen fuel-cell technology that are able to improve vehicle range, and reduce battery recharging time, while maintaining the crucial advantages of high efficiency and local zero emissions. The best working of a fuel-cell propulsion system, in terms of optimum efficiency and performance,

P. Corbo; F. E. Corcione; F. Migliardini; O. Veneri

2006-01-01

373

Investigations on fabrication and lifetime performance of self – air breathing direct hydrogen micro fuel cells  

Microsoft Academic Search

There is an ever – increasing demand for more powerful, compact and longer – life power modules for portable electronic devices for leisure, communication and computing. Micro fuel cells have the potential to replace battery packs for portable electronic appliances because of their high power density, longer operating and standby times, and substantially shorter recharging times. However, fuel cells have

S. Giddey; S. P. S. Badwal; F. T. Ciacchi; D. Fini; B. A. Sexton; F. Glenn; P. W. Leech

2010-01-01

374

Modeled impacts of predicted climate change on recharge and groundwater levels  

NASA Astrophysics Data System (ADS)

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.

Scibek, J.; Allen, D. M.

2006-11-01

375

Electrode performance of romanechite for rechargeable lithium batteries  

Microsoft Academic Search

We studied romanechite, (2×3) tunnel type manganese dioxide, as a positive electrode material for rechargeable lithium batteries. We synthesized the sample by soft chemical techniques, and its chemical composition was Ba0.18MnO2.10·0.42H2O. We obtained a first discharge capacity of 120mAhg?1 (energy density 264mWhg?1). The capacity decreased with cycling. We examined the thermal behavior of this material, revealing its high thermal stability.

Masayuki Tsuda; Hajime Arai; Yasue Nemoto; Yoji Sakurai

2001-01-01

376

Nonflammable gel electrolyte containing alkyl phosphate for rechargeable lithium batteries  

Microsoft Academic Search

A nonflammable polymeric gel electrolyte has been developed for rechargeable lithium battery systems. The gel film consists of poly(vinylidenefluoride-co-hexafluoropropylene) (PVdF-HFP) swollen with lithium hexafluorophosphate (LiPF6) solution in ternary solvent containing trimethyl phosphate (TMP). High ionic conductivity of 6.2mScm?1 at 20°C was obtained for the gel electrolyte consisting of 0.8M LiPF6\\/EC+DEC+TMP (55:25:20) with PVdF-HFP, which is comparable to that of the

Nobuko Yoshimoto; Yoshihiro Niida; Minato Egashira; Masayuki Morita

2006-01-01

377

The Noise Diagnostics of Organic Electrolytes for Rechargeable Lithium Batteries  

NASA Astrophysics Data System (ADS)

We investigated the electrochemical noise of lithium electrode under the current control. Different aprotic organic electrolytes containing different solvents and lithium salts were used as well as anodic and cathodic currents. It was found that level of electrochemical noises depends strongly on the kind of electrolyte. The electrolyte systems with high lithium cycling efficiency and without the dendrite forming posses the low level of noise. This means the electrochemical noises method can be used for express screening organic electrolytes for rechargeable batteries with negative electrode of metal lithium.

Kanevskii, Leonid S.; Grafov, Boris M.; Astafiev, Mikhail G.

2005-08-01

378

Glyme-based nonaqueous electrolytes for rechargeable lithium cells  

Microsoft Academic Search

Poly(ethylene glycol)dimethyl ethers [(CH3O(CH2CH2O)nCH3, n = 1, 2, 3, and 4)] are generally known as “glymes”. This study examines the conductivity, lithium ion solvation state and charge–discharge cycling efficiency of lithium metal anodes in glyme-based electrolytes for rechargeable lithium cells. 1M (M: moll?1) LiPF6 was used as the solute. The properties of the glymes were investigated by using a ternary

S. Tobishima; H. Morimoto; M. Aoki; Y. Saito; T. Inose; T. Fukumoto; T. Kuryu

2004-01-01

379

High capacity anode materials for rechargeable sodium-ion batteries  

SciTech Connect

Electrochemical techniques have been used to study the reversible insertion of sodium into hard-carbon host structures at room temperature. In this paper the authors compare these results with those for lithium insertion in the same materials and demonstrate the presence of similar alkali metal insertion mechanisms in both cases. Despite the gravimetric capacities being lower for sodium than lithium insertion, the authors achieved a reversible sodium capacity of 300 mAh/g, close to that for lithium insertion in graphitic carbon anode materials. Such materials may therefore be useful as anodes in rechargeable sodium-ion batteries.

Stevens, D.A.; Dahn, J.R.

2000-04-01

380

Lithiated manganese oxide cathodes for rechargeable lithium batteries  

Microsoft Academic Search

Lithiated manganese oxides LixMnyO2 prepared at the low temperature of 400-450°C exhibited significantly different electrochemical properties than the spinel phase, LiMn2O4, formed at 650-850°C. The former was nonstoichiometric and yielded a capacity of ~0.7 LiMn2 unit at ~2.8 V in polymer electrolyte-based Li cells. Its excellent rechargeability was demonstrated by more than 100 charge\\/discharge cycles. Spinel Li2Mn4 was formed by

K. M. Abraham; D. M. Pasquariello; T. H. Hguyen; Z. Jiang; D. Peramunage

1996-01-01

381

Chemical lithium extraction from manganese oxides for lithium rechargeable batteries  

Microsoft Academic Search

Chemical lithium extraction has been carried out on the following manganese oxides: the spinel-type compounds LiMn2O4 and Li(4\\/3)Mn(5\\/3)O4, and the rocksalt-related compound Li2MnO3. Lithium can be partially removed chemically from these compounds without destroying the host framework. Some compounds obtained by this method have been tested as cathodic materials in rechargeable lithium cells. Electrochemical results and X-ray diffraction patterns of

F. Lubin; A. Lecerf; M. Broussely; J. Labat

1991-01-01

382

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

SciTech Connect

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.

Charles E. Russell; Tim Minor

2002-08-31

383

Estimating recharge thresholds in tropical karst island aquifers: Barbados, Puerto Rico and Guam  

Microsoft Academic Search

The hydrology and geochemistry of groundwater in tropical island aquifers, such as Barbados, Guam and Puerto Rico, are significantly influenced by tropical climatic conditions. Recharge to these aquifers is the product of regional and local climate patterns that control rainfall. Oxygen isotopes can be used to estimate the amount and timing of recharge on these islands because seasonal fluctuations of

Ian C. Jones; Jay L. Banner

2003-01-01

384

Groundwater recharge in natural dune systems and agricultural ecosystems in the Thar Desert region, Rajasthan, India  

NASA Astrophysics Data System (ADS)

Water and nutrient availability for crop production are critical issues in (semi)arid regions. Unsaturated-zone Cl tracer data and nutrient (NO3 and PO4) concentrations were used to quantify recharge rates using the Cl mass balance approach and nutrient availability in the Thar Desert, Rajasthan, India. Soil cores were collected in dune/interdune settings in the arid Thar Desert (near Jaisalmer) and in rain-fed (nonirrigated) and irrigated cropland in the semiarid desert margin (near Jaipur). Recharge rates were also simulated using unsaturated zone modeling. Recharge rates in sparsely vegetated dune/interdune settings in the Jaisalmer study area are 2.7-5.6 mm/year (2-3% of precipitation, 165 mm/year). In contrast, recharge rates in rain-fed agriculture in the Jaipur study area are 61-94 mm/year (10-16% of precipitation, 600 mm/year). Minimum recharge rates under current freshwater irrigated sites are 50-120 mm/year (8-20% of precipitation). Nitrate concentrations are low at most sites. Similarity in recharge rates based on SO4 with those based on Cl is attributed to a meteoric origin of SO4 and generally conservative chemical behavior in these sandy soils. Modeling results increased confidence in tracer-based recharge estimates. Recharge rates under rain-fed agriculture indicate that irrigation of 20-40% of cultivated land with 300 mm/year should be sustainable.

Scanlon, Bridget R.; Mukherjee, Abhijit; Gates, John; Reedy, Robert C.; Sinha, Amarendra K.

2010-06-01

385

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...

386

MODIS-Aided Statewide Net Groundwater-Recharge Estimation in Nebraska.  

PubMed

Monthly evapotranspiration (ET) rates (2000 to 2009) across Nebraska at about 1-km resolution were obtained by linear transformations of the MODIS (MODerate resolution Imaging Spectroradiometer) daytime surface temperature values with the help of the Priestley-Taylor equation and the complementary relationship of evaporation. For positive values of the mean annual precipitation and ET differences, the mean annual net recharge was found by an additional multiplication of the power-function-transformed groundwater vulnerability DRASTIC-code values. Statewide mean annual net recharge became about 29 mm (i.e., 5% of mean annual precipitation) with the largest recharge rates (in excess of 100 mm/year) found in the eastern Sand Hills and eastern Nebraska. Areas with the largest negative net recharge rates caused by declining groundwater levels due to large-scale irrigation are found in the south-western region of the state. Error bounds of the estimated values are within 10% to 15% of the corresponding precipitation rates and the estimated net recharge rates are sensitive to errors in the precipitation and ET values. This study largely confirms earlier base-flow analysis-based statewide groundwater recharge estimates when considerations are made for differences in the recharge definitions. The current approach not only provides better spatial resolution than available earlier studies for the region but also quantifies negative net recharge rates that become especially important in numerical modeling of shallow groundwater systems. PMID:23216050

Szilagyi, Jozsef; Jozsa, Janos

2012-12-05

387

Polymer electrolyte lithium batteries rechargeability and positive electrode degradation: An AC impedance study  

Microsoft Academic Search

AC impedance measurements of polymer electrolyte-based, symmetrical composite cathode cells were used to probe the effects of the composite cathode composition and fabrication process upon its performance when used in polymer electrolyte-based thin film rechargeable lithium batteries. The relationship between cycling performance and AC impedance measurements were used to elucidate some of the reported failure mechanisms of rechargeable lithium polymer

R. Koksbang; I. I. Olsen; P. E. Tonder; N. Knudsen; D. Fauteux

1991-01-01

388

Estimating Recharge through Playa Lakes to the Southern High Plains Aquifer  

Microsoft Academic Search

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 of the land use surrounding each playa lake on the

K. Rainwater; G. Ganesan; D. Gitz; R. Zartman; W. Hudnall; L. Smith

2009-01-01

389

Recharge into Southern High Plains aquifer—possible mechanisms, unresolved questions  

Microsoft Academic Search

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

Ronit Nativ

1992-01-01

390

Mitigating agricultural impacts on groundwater using distributed managed aquifer recharge ponds  

Microsoft Academic Search

Groundwater is likely to become increasingly important for irrigated agriculture due to anticipated changes to the hydrologic cycle associated with climate change. Protecting the quantity and quality of subsurface water supplies will require flexible management strategies that can enhance groundwater recharge. We present results from a study of managed aquifer recharge (MAR) in central coastal California, and propose the use

C. M. Schmidt; T. A. Russo; A. T. Fisher; A. J. Racz; C. G. Wheat; M. Los Huertos; B. S. Lockwood

2010-01-01

391

Variations in climate and ephemeral channel recharge in southeastern Arizona, United States  

Microsoft Academic Search

Significant variations in interannual and decadal recharge rates are likely in alluvial basins of the semiarid southwestern United States on the basis of decadal variations in climate and precipitation and correlation of El Niño with high rates of winter precipitation and streamflow. A better understanding of the magnitude of recharge variations in semiarid and arid regions would reduce water budget

D. R. Pool

2005-01-01

392

Assessing Recharge and Hydrostratigraphic Model Uncertainty in the Climax Mine Area of the Nevada Test Site  

Microsoft Academic Search

Hydrologic analyses are commonly based on a single conceptual model. Yet hydrologic environments are open and complex, rendering them prone to multiple interpretations and conceptualizations. Considering conceptual model uncertainty is a critical process for the assessment of hydrologic uncertainty. This study assesses recharge and geologic model uncertainty for the Climax Mine area of the Nevada Test Site, Nevada, where recharge

Ming Ye; Karl F. Pohlmann; Jenny B. Chapman; Greg M. Pohll; Donald M. Reeves

393

Statistical analysis of hydrographs and water-table fluctuation to estimate groundwater recharge  

Microsoft Academic Search

Using water-table monitoring data from the National Groundwater Monitoring Network in Korea, groundwater hydrographs were classified into five typical groups. Then, to estimate groundwater recharge, a modified water-table fluctuation (WTF) method was developed from the relation between the cumulative WTF and corresponding precipitation records. Applying this method to different types of hydrographs, the spatial variability of recharge in river basins

Sang-Ki Moon; Nam C Woo; Kwang S Lee

2004-01-01

394

Prospects for enhanced groundwater recharge via infiltration of urban storm water runoff: A case study  

Microsoft Academic Search

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 ecosystems via enhancement of stream base flow. Yet, soil conditions can impact on certain aspects of rain garden performance and

W. D. Shuster; R. Gehring; J. Gerken

395

Comparison of Aquifer Recharge Estimates Based on Measured and Estimated Hydraulic Properties  

Microsoft Academic Search

Because unsaturated hydraulic properties, which are used to estimate recharge, are difficult and time consuming to measure accurately, models that estimate these properties indirectly are often used. Using data from six locations in southern New Jersey that appear to have steady-state flow conditions, five hydraulic property prediction and parameterization techniques were evaluated for recharge estimation. The unsaturated zone at this

K. S. Perkins

2003-01-01

396

Hydrogeochemical evidence for surface water recharge to a shallow regional aquifer in northern Victoria, Australia  

Microsoft Academic Search

The Third, Middle and Reedy Lakes system in northern Victoria is a series of interconnected lakes in which groundwater discharge and recharge occur under seasonal climatic and artificial influences. At high lake levels there is a pronounced mounding effect which tends to cause localised perturbation of flow systems and recharge into the uppermost aquifer. Three hydrostratigraphic units (referred to as

L. A. Chambers; J. G. Bartley; A. L. Herczeg

1996-01-01

397

Mode changing stability of wind turbine in an integrated wind turbine and rechargeable battery system  

Microsoft Academic Search

Power generated by wind turbines changes due to variation in wind speed that is independent of the load power. Rechargeable batteries could be used as a reserve power source to alleviate unbalance between the load power and power generated by wind turbines. A supervisory controller is proposed for an integrated wind turbine-battery system (wind turbine electrically connected to a rechargeable

Christine A. Mecklenborg; Dushyant Palejiya; John F. Hall; Dongmei Chen

2011-01-01

398

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...

399

Inferring time-varying recharge from inverse analysis of long-term water levels  

USGS Publications Warehouse

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.

Dickinson, J. E.; Hanson, R. T.; Ferre, T. P. A.; Leake, S. A.

2004-01-01

400

Chemical modifications of groundwater contaminated by recharge of treated sewage effluent  

Microsoft Academic Search

Long-term monitoring of the chemical composition of recharge sewage effluent and associated contaminated groundwater from the Dan Region Sewage Reclamation Project shows, after 16 years of recharge operation, the presence of a distinct saline plume (up to 400 mg\\/l Cl), extending 1600 m downgradient in the Coastal Plain aquifer of Israel. The recorded electrolyte composition of groundwater in the vicinity

Avner Vengosh; Rami Keren

1996-01-01

401

The Effects of Ashe Juniper on Groundwater Recharge in the Edwards Aquifer  

NASA Astrophysics Data System (ADS)

Understanding groundwater recharge rates has direct relevance for management of the Edwards Aquifer, which serves as the main source of fresh water for the city of San Antonio and surrounding communities. As population around San Antonio continues to grow, so does the demand for water and the stress placed on the aquifer. A method that is commonly believed to augment water yields is brush management. Recently on the Edwards Plateau decreasing streamflow has coincided with increasing juniper density. This has led many to believe that removing juniper would increase available water. Due to its karstic nature, the recharge zone of the Edwards Aquifer is assumed to be a prime location for augmenting water yields through vegetation manipulation. This study assesses the dynamics of recharge and the effects of manipulating surface vegetation. To accomplish this, a shallow cave located in the Edwards Aquifer recharge zone in San Antonio, Texas was instrumented to monitor drip recharge in response to simulated rainfall events. In 2004, simulations were conducted over the cave to measure recharge rates with a dense Ashe juniper canopy. The data and observations from the initial simulations were used to establish a baseline with the juniper in place. In March 2008 the juniper stand was cleared and the rainfall simulations were reproduced in June and July 2008. Results initially indicated that removing the juniper decreases recharge, however, surface runoff was significantly increased. From the results we can conclude that the dynamics of recharge are affected initially following removal of juniper.

Bazan, R. A.; Wilcox, B. P.; Munster, C. L.; Gregory, L. F.

2008-12-01

402

Intrinsically safe 5-V, 4-A: Rechargeable power supply. Information circular\\/1989  

Microsoft Academic Search

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

Sammarco

1989-01-01

403

A ring-oscillator-based active quenching and active recharge circuit for single photon avalanche diodes  

Microsoft Academic Search

This paper proposes a new active quenching and active recharge circuit for single photon avalanche diodes (SPADs). Thanks to the simple ring oscillator architecture, the circuit is one of the most compact active quenching circuits published in the literature. Additionally, a simple modification to the basic version of the circuit allows to measure the hold-off delay and the recharge pulse

M. Gronholm; J. Poikonen; M. Laiho

2009-01-01

404

Voltage regulator for variant light intensity photovoltaic recharging of secondary batteries  

Microsoft Academic Search

A simplified voltage regulator circuit permits varient light intensity photovoltaic recharging of secondary batteries. The regulator circuit electronically shunts serially connected regions of a photovoltaic recharger array to avoid overcharging during periods of high light intensity or full battery charge conditions. The regulator circuitry provides minimal series resistance to the photovoltaic array and requires nominal driving power. The photovoltaic array

Nazimek

1981-01-01

405

Transient-boundary voltage method for measurement of equivalent circuit components of rechargeable batteries  

Microsoft Academic Search

A method is presented for measuring the equivalent circuit components of rechargeable batteries. The temporal discharge–rest–charge–rest sequence of a rechargeable battery is described, using the principles of transient circuit analysis, to derive equations for the battery voltage as a function of time during voltage transients and at the boundaries at transitions between transient phases. The equations lead to a new

K. H. Norian

406

Long-Term Monitoring of Infiltration at a Managed Aquifer Recharge Site Using Electrical Resistivity Probes  

Microsoft Academic Search

As part of an effort to understand the hydrogeologic parameters that influence the performance of a managed aquifer recharge project, four Electrical Resistivity Imaging (ERI) probes were installed beneath an artificial recharge pond to monitor changes in bulk electrical resistivity as a function of time. The probes were three meters long and installed to a depth of two meters below

R. Cockett; A. Pidlisecky; R. J. Knight

2010-01-01

407

Vertical Recharge of a Confined Aquifer in the Fish Farming Area  

Microsoft Academic Search

The rate of vertical groundwater recharge into a confined aquifer is often difficult to estimate due to poor information about confining beds and local pumping activities. Previous studies on a confined aquifer in the coastal plain of Taiwan suggested that its groundwater is primarily recharged laterally from the eastern highland. However, heavy rainfalls that cause all water wells to cease

Y. Chia; W. Liou; T. Lee; Y. Chiu

2004-01-01

408

Rechargeable lithium batteries. (Latest citations from the INSPEC database). Published Search  

SciTech Connect

The bibliography contains citations concerning the design, development, evaluation, and applications of rechargeable lithium batteries. Citations discuss rechargeability, electrolyte formulation, electrode materials, high power capability, thermal management, and overcharge protection. Applications in automotive vehicles, space equipment, computers, and telephones are also discussed. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

NONE

1996-12-01

409

Calculating the average natural recharge in large areas as a factor of their lithology and precipitation  

Microsoft Academic Search

In an area as large as Spain, it is shown by statistical inference on a sample of 875 springs (with discharges greater than 10 l s-1), whose average flow, lithology and catchment areas are known, and which were grouped into regions of contrasting rainfall, that the average annual recharge is a fixed fraction of annual rainfall for each lithology. Recharge

E. Sanz; I. Menéndez Pidal de Navascués; C. Távara

2011-01-01

410

Portrayal of fuzzy recharge areas for water balance modelling - a case study in northern Oman  

NASA Astrophysics Data System (ADS)

The research project IWAS Oman aims at implementing integrated water resources management (IWRM) to a pilot area in Al Batinah, Oman. This requires - amongst others - a realistic assessment of groundwater recharge to the alluvial aquifer which obviously has to be based upon the extension of recharge areas. In this context, the subsequent investigation focuses on the role of vagueness as regards the portrayal of the areas that provide water for particular aquifers. For that purpose, concepts of fuzziness in spatial analysis are applied to describe possible extents of recharge areas. In general, any water assessment is based on clearly delineated boundaries. However, in many cases, aquifer recharge areas are not clearly defined due to the nature of the study area. Hence, surfaces indicating a gradual membership to the recharge area of a particular aquifer are used in this investigation. These surfaces, which are based on available qualitative information, visualise a potential range of spatial extension. With regard to water balance calculations, functional relationships in tabular form are derived as well. Based on a regionalisation approach providing spatially distributed recharge rates, the corresponding recharge volume is calculated. Hence, this methodology provides fuzzy input data for water balance calculations. Beyond the portrayal of one singular aquifer recharge area, this approach also supports the complementary consideration of adjacent areas.

Gerner, A.; Schütze, N.; Schmitz, G. H.

2012-06-01

411

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....

412

Groundwater recharge and evapotranspiration for two natural ecosystems covered with oak and heather  

Microsoft Academic Search

The evapotranspiration and groundwater recharge from two natural areas with high (oak) and low (heath) vegetation were estimated by calibrating a semi-physical numerical soil water and heat model to fit 8 and 7 years of TDR-measurements of water content, respectively. The measurements were made between the surface and 7 m depth. For the oak stand, the estimated annual recharge for

U. L. Ladekarl; K. R. Rasmussen; S. Christensen; K. H. Jensen; B. Hansen

2005-01-01

413

The Guarani Aquifer System: estimation of recharge along the Uruguay-Brazil border  

NASA Astrophysics Data System (ADS)

The cities of Rivera and Santana do Livramento are located on the outcropping area of the sandstone Guarani Aquifer on the Brazil-Uruguay border, where the aquifer is being increasingly exploited. Therefore, recharge estimates are needed to address sustainability. First, a conceptual model of the area was developed. A multilayer, heterogeneous and anisotropic groundwater-flow model was built to validate the conceptual model and to estimate recharge. A field campaign was conducted to collect water samples and monitor water levels used for model calibration. Field data revealed that there exists vertical gradients between confining basalts and underlying sandstones, suggesting basalts could indirectly recharge sandstone in fractured areas. Simulated downward flow between them was a small amount within the global water budget. Calibrated recharge rates over basalts and over outcropping sandstones were 1.3 and 8.1% of mean annual precipitation, respectively. A big portion of sandstone recharge would be drained by streams. The application of a water balance yielded a recharge of 8.5% of average annual precipitation. The numerical model and the water balance yielded similar recharge values consistent with determinations from previous authors in the area and other regions of the aquifer, providing an upper bound for recharge in this transboundary aquifer.

Gómez, Andrea A.; Rodríguez, Leticia B.; Vives, Luis S.

2010-11-01

414

Estimation of pumpage and recharge in alluvial fan topography under multiple irrigation practices  

NASA Astrophysics Data System (ADS)

Estimate small-scale temporal variation in pumpage and recharge on a monthly scale. Identify flow amount in a groundwater system under multiple irrigation practices. Can estimate illegal pumpage for irrigation or non-irrigation use. Recharge sources can be individually identified as rainfall, river, boundary inflow, and irrigation. Semi-arid multiple irrigation region shows huge temporal variation in groundwater budget.

Hsu, Nien-Sheng; Chiang, Chung-Jung; Wang, Chung-Ho; Liu, Chen-Wuing; Huang, Chien-Lin; Liu, Hung-Jen

2013-02-01

415

Likely recharge to permanent groundwater beneath future rehabilitated landforms at Ranger uranium mine, northern Australia  

Microsoft Academic Search

The magnitude of recharge beneath rehabilitated landforms at former mine sites is one of many variables required for a comprehensive assessment of potential future environmental impacts of those sites. The magnitude of net groundwater recharge that may occur on the rehabilitated Range Uranium Mines landform is estimated to be of the order of 2–5% of the incident rainfall, that is,

P. H. Woods

1994-01-01

416

Relation of pathways and transit times of recharge water to nitrate concentrations using stable isotopes  

Microsoft Academic Search

Oxygen and hydrogen stable isotope values of precipitation, irrigation water, soil water, and ground water were used with soil-moisture contents and water levels to estimate transit times and pathways of recharge water in the unsaturated zone of a sand and gravel aquifer. Nitrate-nitrogen (nitrate) concentrations in ground water were also measured to assess their relation to seasonal recharge. Stable isotope

Matthew K. Landon; Geoffrey N. Delin; Stephen C. Komor; Charles P. Regan

2000-01-01

417

Regional Groundwater Recharge and Groundwater Evapotranspiration in Illinois  

NASA Astrophysics Data System (ADS)

Several recent land surface modeling studies have found that the incorporation of groundwater representation can enhance evapotranspiration due to the additional moisture provided by the aquifer. However, there is a lack of regional-scale field evidence to support this finding. The role of shallow unconfined aquifers in supplying water for the evapotranspiration (groundwater evaporation) is investigated in this study based on a comprehensive 22- year (1984-2005) monthly hydroclimatic dataset in Illinois. State-average monthly groundwater recharge and the separation of streamflow components (surface runoff and groundwater runoff) were estimated by soil water balance computations and compared with the previous estimates. The seasonal and interannual variability of groundwater recharge estimates were investigated. It was found that during the summer, the capillary flux from the shallow water table to the root zone soil moisture helps to maintain a high rate of evapotranspiration (~120 mm/month), and its magnitude increases throughout the summer and reaches the maximum of 12 mm/month in August. Neglecting this mechanism in regional water budget studies or land surface modeling may lead to the underestimation of soil moisture and summer evapotranspiration.

Yeh, P.; Famiglietti, J.

2007-12-01

418

Tritium tracer test to estimate aquifer recharge under irrigated conditions  

NASA Astrophysics Data System (ADS)

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.

Jimenez-Martinez, J.; Tamoh, K.; Candela, L.

2009-12-01

419

Electrochemical impedance spectroscopy of lithium-titanium disulfide rechargeable cells  

SciTech Connect

The two-terminal alternating current impedance of lithium-titanium disulfide (Li/TiS[sub 2]) rechargeable cells has been studies as a function of frequency, state-of-charge, and extended cycling. Analysis based on a plausible equivalent circuit model for the Li/TiS[sub 2] cell leads to evaluation of kinetic parameters for the various physicochemical processes occurring at the electrode/electrolyte interfaces. To investigate the causes of cell degradation during extended cycling, the parameters evaluated for cells cycled five times have been compared with the parameters of cells that have been cycled over 600 times. The findings are that the combined ohmic resistance of the electrolyte and electrodes suffers a ten-fold increase after extended cycling, while the charge-transfer resistance and diffusional impedance at the TiS[sub 2]/electrolyte interface are not significantly affected. The results reflect the morphological change and increase in area of the anode due to cycling. The study also shows that overdischarge of a cathode-limited cell causes a decrease in the diffusion coefficient of the lithium ion in the cathode. The study demonstrate the value of electrochemical impedance spectroscopy in investigating failure mechanisms. The approach and methodology followed here can be extended to other rechargeable lithium battery system.

Narayanan, S.R.; Shen, D.H.; Surampudi, S.; Attia, A.I.; Halpert, G. (California Inst. of Technology, Pasadena, CA (United States). Jet Propulsion Lab.)

1993-07-01

420

Large Scale Hydrological Modelling: Parameterisation of Groundwater Recharge  

NASA Astrophysics Data System (ADS)

There is currently worldwide interest in the effect of human activity on the global environment, especially the effect of greenhouse gases and land-use change on the global climate, and models are being developed to study both global and local effects of global changes. This research involves the development and application of GRASP (Groundwater Recharge modelling Approach with a Scaling-up Procedure) intended as a component of UP (Upscaled physically based) large-scale hydrological model. GRASP comprises two modelling schemes: SM (Soil Moisture approach) and TF (Transfer Function approach), both based on the one-dimensional Richards' equation. TF is a transfer function model for inhomogeneous vertical flow in the unsaturated zone and gives the recharge response for a short pulse of infiltration at the ground surface or percolation from the root zone. TF is point-based and its parameters are physically-based, derived using the matric potential and unsaturated hydraulic conductivity functions. SM is a simple, computationally efficient, grid-based, two parameters scheme, which are derived based on TF's point-scale aggregated response. Since TF is linear, upscaled transfer functions can be derived through area-weighted summation of point scale transfer functions. Two applications of GRASP are shown, one using data for Little Washita catchment in the ARRB (USA) and another using data from ABRACOS experiment in Central Amazon (Brazil). Although completely validation of the GRASP model needs more data, as shown, results are quite encouraging.

Pimenteldasilva, L.

2002-12-01

421

Estimating groundwater recharge through tills: a sensitivity analysis of soil moisture budgets and till properties in Ireland  

Microsoft Academic Search

The study highlights the dangers of limiting recharge calculations in humid climates to meteorological and soil considerations.\\u000a It highlights the importance of developing a conceptual understanding of the influence of geology on recharge mechanisms and\\u000a recharge rates. Uncertainties in recharge estimates through tills are examined by a study of the available literature, combined\\u000a with sensitivity analyses of soil moisture budget

Vincent P. Fitzsimons; Bruce D. R. Misstear

2006-01-01

422

Recharge sources and hydrogeochemical evolution of groundwater in the coal-mining district of Jiaozuo, China  

NASA Astrophysics Data System (ADS)

Investigations in the Jiaozuo coal-mining district (China) aim to link water-inrush aquifers with the sources of groundwater recharge. Concentrations of TDS, HCO{3/-}, Cl- and Na+ in the groundwater samples gradually decrease with increasing depth; in contrast, the factor 1 value of the Q-mode analysis gradually increases, which indicates that the deep groundwater may upflow, recharging the aquifers near the faulted zone. Some groundwater samples (above the local meteoric water line and `evaporation line 1') may originate from recharge by infiltrating local rainfall. Spring and river samples are symmetrically distributed on the regression line of the Ordovician and Carboniferous limestone aquifer groundwater (?2H = 3.76 × ?18O - 31.77) and may, therefore, originate from groundwater recharge in the northern Taihang mountains. This mechanism is supported by the observation that groundwater levels change with rainfall. According to radiocarbon residence-time estimates, two groundwater sample sites may have been recharged during the late glacial stage.

Huang, Pinghua; Chen, Jiansheng

2012-06-01

423

Selection Site for Artificial Recharge of Groundwater in Hard Rocks Using ANN with Special Reference to India  

NASA Astrophysics Data System (ADS)

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.

Banerjee, Pallavi

2010-05-01

424

Integrated Modeling of Infiltration, Evapotranspiration, Recharge, Subsurface Flow, Surface Runoff, and River Flow with First Principle, Physics-based Approaches  

NASA Astrophysics Data System (ADS)

Over the past 30 years, progress in the development of physics-based models for individual processes of infiltration, evapotranspiration, recharge, moisture redistribution in vadose zone, groundwater flow, surface runoff, and river flow has been remarkable. However, these individual processes are continuously and dynamically coupled over various spatial and temporal scales. In the past, each individual process was often investigated assuming other coupling and influencing processes were a priori. For example, to model overland flow (surface runoff), it was often implicitly assumed that the infiltration was known and the feedback from groundwater flow and river flow were not explicitly enforced. Integrated approaches to modeling coupled processes have gained momentum recently. Many integrated models have achieved the coupling via external or internal linkage of individual process-level models. As a result, these models often have to introduce undue empiricism. This paper presents the development of an integrated numerical model of the aforementioned processes. A rigorous coupling of these hydrological processes is achieved with the first principle approach by imposing the continuity of volumetric fluxes and state variables. In this integrated model, any process between two media is the natural consequence of interaction and feedback between processes occurring in the media. For example, infiltration and recharge are spatially and temporally varied and are the consequence of interacting flow processes on the land surface (overland) and in the subsurface media and rivers. Numerical implementations of the theoretical coupling are thoroughly discussed. Several example problems will be used to demonstrate theoretical and application aspects of this model. Key Words: Infiltration, Evapotranspiration, Recharge, Surface Runoff, Groundwater Flow, River Flow, Numerical Model

Yeh, G.; Cheng, H.; Lin, H.; Zhang, F.; Edris, E. V.; Richards, D. R.

2003-12-01

425

Modeling Integrated Cave Drip Recharge Data using DReAM (Daily Recharge Assessment Model) in a Dry Eastern Mediterranean Area, Sif Cave - Israel  

NASA Astrophysics Data System (ADS)

Understanding recharge mechanisms and controls in karst regions is extremely important for managing water resources because of the dynamic nature of the system. To better understand this mechanism, a cave in the recharge area of the karstic Western Mountain Aquifer (WMA) of Israel was equipped to measure precipitation infiltration (2006-2008) by collecting integrated water drips from three areas in the cave (14, 46, and 52 m2 areas). Barrels equipped with pressure transducers record drip rate and volume for each of the three areas and enable estimation of recharge. A water budget model - DReAM (Daily Recharge Assessment Model) was used to quantify and predict infiltration behavior at the cave. DReAM includes calculations of all water cycle components - precipitation, evapotranspiration, runoff and recharge. The model was calibrated and validated using two independent sets of values, providing good agreement between calculated and observed data. Modeling results agree with previous studies that show: 1) three distinct flow paths (slow, intermediate, and fast flows) of water infiltrating at the cave; 2) a threshold of ~100 mm rain at the beginning of the rainy season for infiltration to begin; and 3) a decrease in lag time between rain events and infiltration response throughout the rainy season. This modeling tool and analysis approach can translate precipitation to groundwater recharge which will be very important for projecting future water resources in response to climate variability.

Anker, Y.; Sheffer, N. A.; Scanlon, B. R.; Gimburg, A.; Morin, E.

2010-12-01

426

Lubricity of military jet fuels  

Microsoft Academic Search

In 1954, a corrosion inhibitor additive was required in JP-4, a wide cut gasoline type aviation turbine fuel, to alleviate corrosion carry-over from ground fuel systems to aircraft. The additive was blamed for fuel filtration problems and removed from the JP-4 specification in 1965. Almost immediately, the U.S. Air Force started experiencing lubricity problems with fuel pumps and controllers. Fuel

P. D. Liberio; J. M. Garver

1995-01-01

427

Chloride-mass-balance for predicting increased recharge after land-use change  

SciTech Connect

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.

Gee, G.W.; Zhang, Z.F.; Tyler, S.W.; Albright, W.H.; Singleton, M.J.

2004-02-23

428

RELAP5 \\/ MOD3.2 analysis of INSC standard problem INSCSP - R7 : void fraction distribution over RBMK fuel channel height for experiments performed in the ENTEK BM test facility  

Microsoft Academic Search

The RELAP5\\/MOD3.2 computer program has been used to analyze a series of tests investigating void fraction distribution over height in RBMK fuel channels performed in Facility BM at the ENTEK. This is RBMK Standard Problem 7 in Joint Project 6, which is the investigation of Computer Code Validation for Transient Analysis of RBMK and VVER Reactors, between the United States

Garner

2002-01-01

429

RELAP5\\/MOD3.2 analysis of INSC standard problem INSCSP - R7 : void fraction distribution over RBMK fuel channel height for experiments performed in the ENTEK BM test facility  

Microsoft Academic Search

The RELAP5\\/MOD3.2 computer program has been used to analyze a series of tests investigating void fraction distribution over height in RBMK fuel channels performed in Facility BM at the ENTEK. This is RBMK Standard Problem 7 in Joint Project 6, which is the investigation of Computer Code Validation for Transient Analysis of RBMK and VVER Reactors, between the United States

Garner

2002-01-01

430

Spatial distribution of groundwater recharge in SOUTH KOREA applying GIS and multivariate statistics to water-table fluctuation  

Microsoft Academic Search

This study is objected to determine areal estimates and spatial variations of groundwater recharges in entire inland of South Korea. Relationships between groundwater recharge ratio and various hydrogeological factors were quantified, and the contributions of each factor were evaluated. For this purpose, firstly, a modified water-table fluctuation method was developed to calculate the recharge ratio using cumulative precipitation and its

S. Moon; N. Woo; K. Lee

2003-01-01

431

Climate Change Effects on Groundwater Recharge East of Yucca Mountain  

NASA Astrophysics Data System (ADS)

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.

Woocay, A.; Walton, J. C.

2007-12-01

432

Use of Constructed Wetlands for Polishing Recharge Wastewater  

NASA Astrophysics Data System (ADS)

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.

Cardwell, W.

2009-12-01

433

Energy-constrained open-system magmatic processes IV: Geochemical, thermal and mass consequences of energy-constrained recharge, assimilation and fractional crystallization (EC-RAFC)  

SciTech Connect

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.

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

434

A Literature Review-Problem Definition Studies on Selected Toxic Chemicals. Volume 1. Occupational Health and Safety Aspects of Diesel Fuel and White Smoke Generated from It.  

National Technical Information Service (NTIS)

Literature is reviewed (75 references) covering analysis, physical and chemical properties, human and animal toxicology, mammalian pharmacokinetics, industrial standards and occupational hazards of diesel fuel and white smoke (an aerosol mixture of diesel...

D. Liss-Suter R. Mason

1978-01-01

435

Comparative analysis of selected fuel cell vehicles  

SciTech Connect

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.

NONE

1993-05-07

436

Improvement in the capacity and safety of lithium/inorganic electrolyte sulfur dioxide rechargeable cells, phase 2  

NASA Astrophysics Data System (ADS)

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.

Schlaikjer, Carl R.; Jones, Medlinda D.; Johnson, Arden P.; Torkelson, James E.; Vanschalkwijk, Walter

1990-11-01

437

Application of Geographical Information System for Identification of Potential Groundwater Artificial Recharge Zones in Hard Rock Terrain  

NASA Astrophysics Data System (ADS)

There are several methods which are employed to delineate the groundwater artificial recharge potential zones. Remote sensing and geographical information system (GIS) technique provides an advantage of having access to large coverage, even in inaccessible areas. It is rapid and cost-effective tool in producing valuable data on geology, geomorphology, lineaments, slope etc. Detail analysis of drainage, geology, lineament, geomorphology and slope has been carried out in the hard rock terrain in Andhra Pradesh, India. These data have been digitized and finally integrated through the application of GIS to decipher groundwater potential zones in the study area. These various data are prepared in the form of thematic map using geographical information system (GIS) software tool. In order to get all these information in the form of thematic map unified, it is essential to integrate these data with appropriate factor. Therefore, all information are integrated through the application of GIS. Various thematic maps are reclassified on the basis of weightage assigned and brought into the "Raster Calculator" function of Spatial Analysist tool for integration. In the recent years digital technique is used to integrate various data to solve problems related to groundwater. In the present study approach of remote sensing and GIS technique is used for ground water exploration and identification of artificial recharge sites.

Prasad, R. K.; Banerjee, Pallavi; Singh, V. S.

2010-05-01

438

Overcharge protection for rechargeable lithium polymer electrolyte batteries  

SciTech Connect

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.

Richardson, T.J.; Ross, P.N. Jr. [Lawrence Berkeley National Lab., CA (United States). Materials Sciences Div.

1996-12-01

439

New amorphous thin-film lithium electrolyte and rechargeable microbattery  

SciTech Connect

Sputtering of Li{sub 3}PO{sub 4} in pure N{sub 2} results in the formation of an amorphous lithium electrolyte that is stable in contact with lithium and has electrical properties that are suitable for application in a thin-film cell. Thin-film rechargeable lithium cells have been fabricated and characterized using this electrolyte between a lithium anode and an amorphous vanadium oxide cathode. The open circuit voltage of the cell is 3.6 to 3.7 V, and it has a capacity of 130 {mu}Ah/cm{sup 2} when discharged to 1.5 V. The ac impedance of the cells measured at different stages of discharge indicate a significant decrease in internal resistance at about the midpoint of the discharge.

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

1992-02-01

440

Safety and performance of Tadiran TLR-7103 rechargeable batteries  

SciTech Connect

In this paper the authors report on the characteristics and performance of a new rechargeable Li-Li{sub x}MnO{sub 2} 3 V battery system developed at Tadiran. The behavior of AA cells of an 800 to 750 mAh capacity is described in terms of charge-discharge curves, cycle life, and low-temperature and high-current performance. At charging regimes around C/10, more than 350 cycles at 100% DOD could be obtained. These batteries have a unique cell chemistry based on LiAsF{sub 6}/1,3-dioxolane/tributyl amine electrolyte solutions which provide internal safety mechanisms that protect the cells from short circuit, overcharge, and thermal runaway upon heating up to 135 C. This behavior is due to the fact that the electrolyte solution is stable at low-to-medium temperatures but polymerizes at temperatures over 125 C.

Mengeritsky, E.; Dan, P. [Tadiran Battery Division, Rehovoth (Israel); Weissman, I.; Zaban, A.; Aurbach, D. [Bar-Ilan Univ., Ramat Gan (Israel). Dept. of Chemistry

1996-07-01

441

Chemical lithium extraction from manganese oxides for lithium rechargeable batteries  

NASA Astrophysics Data System (ADS)

Chemical lithium extraction has been carried out on the following manganese oxides: the spinel-type compounds LiMn2O4 and Li(4/3)Mn(5/3)O4, and the rocksalt-related compound Li2MnO3. Lithium can be partially removed chemically from these compounds without destroying the host framework. Some compounds obtained by this method have been tested as cathodic materials in rechargeable lithium cells. Electrochemical results and X-ray diffraction patterns of cycled cathodes are presented. Electrochemical insertion/extraction of Li(+) ions occurs with tetragonal/cubic distortion in the spinel framework, whereas Li(+) ions can move in compounds having the rocksalt structure, without significant modification of the X-ray patterns.

Lubin, F.; Lecerf, A.; Broussely, M.; Labat, J.

1991-03-01

442

Using HDR (Hot Dry Rock) technology to recharge The Geysers  

SciTech Connect

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.

Brown, D.W.; Robinson, B.A.

1990-01-01

443

Inorganic electrolyte solutions and gels for rechargable lithium batteries  

SciTech Connect

A class of inorganic oxychloride compounds have been evaluated for use as electrolytic solvents in rechargeable lithium batteries. Compared with SO{sub 2}-based electrolytes, these showed much improved safety while maintaining room temperature conductivities of 10{sup {minus}3}--10{sup {minus}2} S/cm and electrochemical voltage windows of 4.5--5.5 vs. Li{sup +}/Li and supporting reversible lithium metal deposition/stripping. With the addition of 2 {approximately} 5% polymer, the solutions acquire rubbery character with little loss of conductivity and no change in electrochemical stability. Preliminary charge/discharge tests with intercalation-type cathode as well as sulfur-based cathode showed that these inorganic electrolytes can operate with excellent reversibility.

Xu, K.; Day, N.D.; Angell, C.A. [Arizona State Univ., Tempe, AZ (United States). Dept. of Chemistry

1996-09-01

444

Vadose zone-attenuated artificial recharge for input to a ground water model.  

PubMed

Accurate representation of artificial recharge is requisite to calibration of a ground water model of an unconfined aquifer for a semiarid or arid site with a vadose zone that imparts significant attenuation of liquid transmission and substantial anthropogenic liquid discharges. Under such circumstances, artificial recharge occurs in response to liquid disposal to the vadose zone in areas that are small relative to the ground water model domain. Natural recharge, in contrast, is spatially variable and occurs over the entire upper boundary of a typical unconfined ground water model. An improved technique for partitioning artificial recharge from simulated total recharge for inclusion in a ground water model is presented. The improved technique is applied using data from the semiarid Hanford Site. From 1944 until the late 1980s, when Hanford's mission was the production of nuclear materials, the quantities of liquid discharged from production facilities to the ground vastly exceeded natural recharge. Nearly all hydraulic head data available for use in calibrating a ground water model at this site were collected during this period or later, when the aquifer was under the diminishing influence of the massive water disposals. The vadose zone is typically 80 to 90 m thick at the Central Plateau where most production facilities were located at this semiarid site, and its attenuation of liquid transmission to the aquifer can be significant. The new technique is shown to improve the representation of artificial recharge and thereby contribute to improvement in the calibration of a site-wide ground water model. PMID:17600580

Nichols, William E; Wurstner, Signe K; Eslinger, Paul W

445

Artificial recharge experiments on the Ship Creek alluvial fan, Anchorage, Alaska  

USGS Publications Warehouse

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)

Anderson, Gary S.

1977-01-01