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1

Mesoporous ?-MnO 2\\/Pd catalyst air electrode for rechargeable lithium–air battery  

Microsoft Academic Search

Rechargeable lithium–air battery is studied using Pd\\/mesoporous ?-MnO2 air composite electrode. In the present work, we have studied the preparation and electrochemical performance of ordered mesoporous ?-MnO2 as a cathode catalyst for rechargeable Li–air batteries. ?-MnO2 was prepared by reduction of KMnO4 solution in acidic aqueous solution followed by successive proton and alkali-ion exchange method. ?-MnO2 with high surface area

Arjun Kumar Thapa; Tatsumi Ishihara

2011-01-01

2

MnO 2 nanoflakes coated on multi-walled carbon nanotubes for rechargeable lithium-air batteries  

Microsoft Academic Search

Manganese dioxide (MnO2) nanoflakes were uniformly coated on multi-walled carbon nanotubes (MWNTs) by immersing MWNTs into an aqueous KMnO4 solution. Directly using the MnO2\\/MWNT composites (containing 40wt.% MWNTs) as lithium-air battery electrodes enhances kinetics of the oxygen reduction and evolution reactions, thereby effectively improving energy efficiency and reversible capacity.

Jiaxin Li; Ning Wang; Yi Zhao; Yunhai Ding; Lunhui Guan

2011-01-01

3

Oxidative Transformation of 17?-estradiol by MnO 2 in Aqueous Solution  

Microsoft Academic Search

17?-Estradiol (E2) is known as a natural endocrine disruptor and often found in municipal sewage. Batch experiments were conducted\\u000a to assess the oxidative transformation of E2 in aqueous solutions by MnO2 and the probable degradation pathway. The results suggested that E2 could be degraded by MnO2, and the oxidation reaction deviated from pseudo-first-order kinetics due to the accumulation of reaction

Liying Jiang; Cheng Huang; Jianmeng Chen; Xiao Chen

2009-01-01

4

Preparation of MnO 2 nanoparticles by directly mixing potassium permanganate and polyelectrolyte aqueous solutions  

Microsoft Academic Search

Well-stable MnO2 nanoparticles were prepared by directly mixing potassium permanganate and polyelectrolyte aqueous solutions, with the use of polyelectrolyte to serve both as a reducing agent and a protective agent. Such nanoparticles were characterized by transmission electron microscopy (TEM) and X-ray photoelectron spectra (XPS), and their growth kinetics was further traced by in situ UV–vis spectra.

Yonglan Luo

2007-01-01

5

pH sensing in aqueous solutions using a MnO 2 thin film electrodeposited on a glassy carbon electrode  

Microsoft Academic Search

An electrolysis technique at a constant potential was used to develop a highly reproducible and fast elaboration method of adherent manganese dioxide thin films on a glassy carbon electrode from aqueous solutions containing sulfuric acid and manganese sulfate. The resulting films were found to have a nanostructured character presumably due rather to birnessite (?-MnO2) than to ?-MnO2, as suggested by

N. Cherchour; C. Deslouis; B. Messaoudi; A. Pailleret

2011-01-01

6

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

7

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

8

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

9

Redox Active Layer-by-Layer Structures containing MnO2 Nanoparticles  

SciTech Connect

Nanoscale materials provide unique properties that will enable new technologies and enhance older ones. One area of intense activity in which nanoscale materials are being used is in the development of new functional materials for battery applications. This effort promises superior materials with properties that circumvent many of the problems associated with traditional battery materials. Previously we have worked on several approaches for using nanoscale materials for application as cathode materials in rechargeable Li batteries. Our recent work has focused on synthesizing MnO2 nanoparticles and using these in layer-by-layer (LbL) structures to probe the redox properties of the nanoparticles. We show that the aqueous colloidal nanoparticles produced by butanol reduction of tetramethylammonium permanganate can be trapped in thin films using a layer-by-layer deposition approach, and that these films are both redox active and exhibit kinetically facile electrochemical responses. We show cyclic voltammetry of MnO2 colloidal nanoparticles entrapped in a LbL thin film at an ITO electrode surface using poly(diallyldimethylammonium chloride) (PDDA). CV experiments demonstrate that Li+ insertion accompanies Mn(IV) reduction in LiClO4 supporting electrolytes, and that reduction is hindered in supporting electrolytes containing only tetrabutylammonium cations. We also show that electron propagation through multilayer films is facile, suggesting that electrons percolate through the films via electron exchange between nanoparticles.

Bazito, Fernanda; O'Brien, Robert; Buttry, Daniel A.

2005-02-01

10

Rechargeable Ni-Li battery integrated aqueous/nonaqueous system.  

PubMed

A rechargeable Ni-Li battery, in which nickel hydroxide serving as a cathode in an aqueous electrolyte and Li metal serving as an anode in an organic electrolyte were integrated by a superionic conductor glass ceramic film (LISICON), was proposed with the expectation to combine the advantages of both a Li-ion battery and Ni-MH battery. It has the potential for an ultrahigh theoretical energy density of 935 Wh/kg, twice that of a Li-ion battery (414 Wh/kg), based on the active material in electrodes. A prototype Ni-Li battery fabricated in the present work demonstrated a cell voltage of 3.47 V and a capacity of 264 mAh/g with good retention during 50 cycles of charge/discharge. This battery system with a hybrid electrolyte provides a new avenue for the best combination of electrode/electrolyte/electrode to fulfill the potential of high energy density as well as high power density. PMID:19803514

Li, Huiqiao; Wang, Yonggang; Na, Haitao; Liu, Haimei; Zhou, Haoshen

2009-10-28

11

Catalytic characteristics of MnO2 nanostructures for the O2 reduction process  

NASA Astrophysics Data System (ADS)

Nanorods with an ? type MnO2 structure and a diameter ranging from 25 to 40 nm, along with tipped needles with a ? MnO2 structure and a diameter of 100 nm were obtained. The 25 nm diameter ? MnO2 nanorods showed the best catalytic activity for dissociation of HO2 - formed during oxygen reduction in a KOH solution. The MnO2 nanostructures preferably followed a two-electron oxygen reduction mechanism in a LiOH solution. The size of the catalyst also affected the specific capacities of the non-aqueous Li/O2 batteries fabricated using the MnO2 based air electrode. The highest specific capacity of 1917 mA h g - 1 was obtained for an ? MnO2 nanorod catalyst having a diameter of 25 nm. The cation present in the MnO2 nanostructures appears to determine the catalytic activity of MnO2.

Kalubarme, Ramchandra S.; Cho, Min-Seung; Yun, Kwi-Sub; Kim, Tae-Sin; Park, Chan-Jin

2011-09-01

12

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

13

Core-shell sulfur@polypyrrole composites as high-capacity materials for aqueous rechargeable batteries.  

PubMed

In order to explore the potential application of sulfur in aqueous rechargeable batteries, core-shell sulfur-polypyrrole (S@PPy) composites were prepared through a novel one-pot and surfactant-free method. Sulfur exhibits a very high capacity of 473 mA h g(-1) and good cycling stability in an aqueous Li(2)SO(4) electrolyte due to the polypyrrole coating. PMID:23314835

Shao, Jie; Li, Xinyong; Zhang, Li; Qu, Qunting; Zheng, Honghe

2013-02-21

14

Structure and Manufacturing Process of MnO2 Counter Electrode in Niobium Suboxide Capacitors  

NASA Astrophysics Data System (ADS)

The influence of iterative heat treatment of impregnated aqueous Mn(NO3)2 solution on the microstructure of the produced MnO2 has been investigated in the fabrication process for niobium suboxide capacitors. We separate the whole process into two stages: At the early stage of impregnations in Mn(NO3)2 solution (with specific density less than 1.35 g/cm3), the produced MnO2 grains with equiaxed nanocrystalline morphology are mainly located in the inner space and pores, avoiding the performance deterioration due to the electrical conductivity anisotropy of columnar texture in NbO capacitors. For impregnation in Mn(NO3)2 solutions with specific density greater than 1.35 g/cm3, MnO2 grains in the inner space and pores continue to grow and present a hexagonal pyramid shape. At this stage, MnO2 starts to be produced on the outer surface of pellets and exhibits a cluster morphology that consists of MnO2 grains with size between 30 nm and 80 nm. The electrical performance of NbO capacitors has been optimized by adjusting the impregnation times and sequence. By alternately impregnating in Mn(NO3)2 solutions with specific densities of 1.23 g/cm3 and 1.35 g/cm3, MnO2 grains are better combined and the internal space of the pellets is fully filled. Impregnation in Mn(NO3)2 solutions with low specific densities (1.10 g/cm3 and 1.23 g/cm3) in dry atmosphere produces a denser MnO2 layer in the internal space, leading to improved capacitor performance.

Chen, Liqin; Li, Bo; Qi, Zhaoxiong; Guo, Hai; Zhou, Ji; Li, Longtu

2013-10-01

15

Different crystallographic one-dimensional MnO2 nanomaterials and their superior performance in catalytic phenol degradation.  

PubMed

Three one-dimensional MnO2 nanoparticles with different crystallographic phases, ?-, ?-, and ?-MnO2, were synthesized, characterized, and tested in heterogeneous activation of Oxone for phenol degradation in aqueous solution. The ?-, ?-, and ?-MnO2 nanostructured materials presented in morphologies of nanowires, nanorods, and nanofibers, respectively. They showed varying activities in activation of Oxone to generate sulfate radicals for phenol degradation depending on surface area and crystalline structure. ?-MnO2 nanowires exhibited the highest activity and could degrade phenol in 60 min at phenol concentrations ranging in 25-100 mg/L. It was found that phenol degradation on ?-MnO2 followed first order kinetics with an activation energy of 21.9 kJ/mol. The operational parameters, such as MnO2 and Oxone loading, phenol concentration and temperature, were found to influence phenol degradation efficiency. It was also found that ?-MnO2 exhibited high stability in recycled tests without losing activity, demonstrating itself to be a superior heterogeneous catalyst to the toxic Co3O4 and Co(2+). PMID:23651050

Saputra, Edy; Muhammad, Syaifullah; Sun, Hongqi; Ang, H M; Tadé, M O; Wang, Shaobin

2013-05-22

16

Electrochemical characterization of manganese oxide cathode materials based on Na 0.4MnO 2  

Microsoft Academic Search

Cathode materials for lithium rechargeable batteries were prepared from Na0.4MnO2 by solution and molten salt ion-exchanges. The former process results in partial replacement of sodium while the latter results in complete exchange. The discharge characteristics depend upon the sodium content, with the partially lithiated material exhibiting hysteresis in the charge\\/discharge profile and differential capacity plots from stepped potential experiments. For

Felix Hu; Marca M. Doeff

2004-01-01

17

Three-dimensional ordered macroporous MnO2/carbon nanocomposites as high-performance electrodes for asymmetric supercapacitors.  

PubMed

MnO2/carbon composites with ultrathin MnO2 nanofibers (diameter of 5-10 nm) uniformly deposited on three dimensional ordered macroporous (3DOM) carbon frameworks were fabricated via a self-limiting redox process. The MnO2 nanofibers provide a large surface area for charge storage, whereas the 3DOM carbon serves as a desirable supporting material providing rapid ion and electron transport through the composite electrodes. Cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy (EIS) were used to characterize the capacitive performance of these composites. Optimization of the composition results in a composite with 57 wt% MnO2 content, which gives both a high specific capacitance (234 F g(-1) at a discharge current of 0.1 A g(-1)) and good rate capability (52% retention of the capacitance at 5 A g(-1)). An asymmetric supercapacitor was fabricated by assembling the optimized MnO2/carbon composite as the positive electrode and 3DOM carbon as the negative electrode. The asymmetric supercapacitor exhibits superior electrochemical performances, which can be reversibly charged and discharged at a maximum cell voltage of 2.0 V in 1.0 M Na2SO4 aqueous electrolyte, delivering both high energy density (30.2 W h kg(-1)) and power density (14.5 kW kg(-1)). Additionally, the asymmetric supercapacitor exhibits an excellent cycle life, with 95% capacitance retained after 1000 cycles. PMID:24141452

Yang, Chunzhen; Zhou, Ming; Xu, Qian

2013-10-21

18

An Aqueous Rechargeable Lithium Battery Using Coated Li Metal as Anode  

PubMed Central

New energy industry including electric vehicles and large-scale energy storage in smart grids requires energy storage systems of good safety, high reliability, high energy density and low cost. Here a coated Li metal is used as anode for an aqueous rechargeable lithium battery (ARLB) combining LiMn2O4 as cathode and 0.5?mol l?1 Li2SO4 aqueous solution as electrolyte. Due to the “cross-over” effect of Li+ ions in the coating, this ARLB delivers an output voltage of about 4.0?V, a big breakthrough of the theoretic stable window of water, 1.229?V. Its cycling is very excellent with Coulomb efficiency of 100% except in the first cycle. Its energy density can be 446?Wh kg?1, about 80% higher than that for traditional lithium ion battery. Its power efficiency can be above 95%. Furthermore, its cost is low and safety is much reliable. It provides another chemistry for post lithium ion batteries.

Wang, Xujiong; Hou, Yuyang; Zhu, Yusong; Wu, Yuping; Holze, Rudolf

2013-01-01

19

An aqueous rechargeable lithium battery using coated Li metal as anode.  

PubMed

New energy industry including electric vehicles and large-scale energy storage in smart grids requires energy storage systems of good safety, high reliability, high energy density and low cost. Here a coated Li metal is used as anode for an aqueous rechargeable lithium battery (ARLB) combining LiMn2O4 as cathode and 0.5?mol l(-1) Li2SO4 aqueous solution as electrolyte. Due to the "cross-over" effect of Li(+) ions in the coating, this ARLB delivers an output voltage of about 4.0?V, a big breakthrough of the theoretic stable window of water, 1.229?V. Its cycling is very excellent with Coulomb efficiency of 100% except in the first cycle. Its energy density can be 446?Wh kg(-1), about 80% higher than that for traditional lithium ion battery. Its power efficiency can be above 95%. Furthermore, its cost is low and safety is much reliable. It provides another chemistry for post lithium ion batteries. PMID:23466633

Wang, Xujiong; Hou, Yuyang; Zhu, Yusong; Wu, Yuping; Holze, Rudolf

2013-01-01

20

Electrical properties of pyrolytic MnO 2 layers  

Microsoft Academic Search

MnO2 samples have been prepared by the pyrolytic decomposition of manganese nitrate in different atmospheres: dry air and air saturated with water vapour. The influence of the atmosphere on the kinetics of the manganese nitrate decomposition and on several physical properties of the resulting MnO2, such as density, grain size, crystalline structure, resistivity and activation energy for electrical conduction, has

J. M. Albella; L. Fernández-Navarrete; J. M. Martínez-Duart

1981-01-01

21

High-performance rechargeable lithium-iodine batteries using triiodide/iodide redox couples in an aqueous cathode.  

PubMed

Development of promising battery systems is being intensified to fulfil the needs of long-driving-ranged electric vehicles. The successful candidates for new generation batteries should have higher energy densities than those of currently used batteries and reasonable rechargeability. Here we report that aqueous lithium-iodine batteries based on the triiodide/iodide redox reaction show a high battery performance. By using iodine transformed to triiodide in an aqueous iodide, an aqueous cathode involving the triiodide/iodide redox reaction in a stable potential window avoiding water electrolysis is demonstrated for lithium-iodine batteries. The high solubility of triiodide/iodide redox couples results in an energy density of ~ 0.33?kWh?kg(-1), approximately twice that of lithium-ion batteries. The reversible redox reaction without the formation of resistive solid products promotes rechargeability, demonstrating 100 cycles with negligible capacity fading. A low cost, non-flammable and heavy-metal-free aqueous cathode can contribute to the feasibility of scale-up of lithium-iodine batteries for practical energy storage. PMID:23695690

Zhao, Yu; Wang, Lina; Byon, Hye Ryung

2013-01-01

22

Hydrothermal synthesis of MnO2/CNT nanocomposite with a CNT core/porous MnO2 sheath hierarchy architecture for supercapacitors  

PubMed Central

MnO2/carbon nanotube [CNT] nanocomposites with a CNT core/porous MnO2 sheath hierarchy architecture are synthesized by a simple hydrothermal treatment. X-ray diffraction and Raman spectroscopy analyses reveal that birnessite-type MnO2 is produced through the hydrothermal synthesis. Morphological characterization reveals that three-dimensional hierarchy architecture is built with a highly porous layer consisting of interconnected MnO2 nanoflakes uniformly coated on the CNT surface. The nanocomposite with a composition of 72 wt.% (K0.2MnO2·0.33 H2O)/28 wt.% CNT has a large specific surface area of 237.8 m2/g. Electrochemical properties of the CNT, the pure MnO2, and the MnO2/CNT nanocomposite electrodes are investigated by cyclic voltammetry and electrochemical impedance spectroscopy measurements. The MnO2/CNT nanocomposite electrode exhibits much larger specific capacitance compared with both the CNT electrode and the pure MnO2 electrode and significantly improves rate capability compared to the pure MnO2 electrode. The superior supercapacitive performance of the MnO2/CNT nancomposite electrode is due to its high specific surface area and unique hierarchy architecture which facilitate fast electron and ion transport.

2012-01-01

23

Highly selective lithium recovery from brine using a ?-MnO2-Ag battery.  

PubMed

The demand for lithium has greatly increased with the rapid development of rechargeable batteries. Currently, the main lithium resource is brine lakes, but the conventional lithium recovery process is time consuming, inefficient, and environmentally harmful. Rechargeable batteries have been recently used for lithium recovery, and consist of lithium iron phosphate as a cathode. These batteries feature promising selectivity between lithium and sodium, but they suffer from severe interference from coexisting magnesium ions, an essential component of brine, which has prompted further study. This study reports on a highly selective and energy-efficient lithium recovery system using a rechargeable battery that consists of a ?-MnO2 positive electrode and a chloride-capturing negative electrode. This system can be used to recover lithium from brine even in the presence of magnesium ions as well as other dissolved cations. In addition, lithium recovery from simulated brine is successfully demonstrated, consuming 1.0 W h per 1 mole of lithium recovered, using water similar to that from the artificial brine, which contains various cations (mole ratio: Na/Li ? 15.7, K/Li ? 2.2, Mg/Li ? 1.9). PMID:23595419

Lee, Jaehan; Yu, Seung-Ho; Kim, Choonsoo; Sung, Yung-Eun; Yoon, Jeyong

2013-04-17

24

Electrochemical properties of rechargeable aqueous lithium ion batteries with an olivine-type cathode and a Nasicon-type anode  

Microsoft Academic Search

Rechargeable aqueous lithium ion batteries have been developed by using olivine LiMn0.05Ni0.05Fe0.9PO4 as cathode material, Nasicon LiTi2(PO4)3 as anode material, and saturated Li2SO4 solution as electrolyte. The cycling performance and rate capability of these batteries have been investigated. At a current density of 0.2mA\\/cm2, the initial discharge capacity of the battery was approximately 103.9mAh\\/g, and the potential plateau was located

Xiao-Hong Liu; Taishi Saito; Takayuki Doi; Shigeto Okada; Jun-ichi Yamaki

2009-01-01

25

LiMn2O4 nanotube as cathode material of second-level charge capability for aqueous rechargeable batteries.  

PubMed

LiMn2O4 nanotube with a preferred orientation of (400) planes is prepared by using multiwall carbon nanotubes as a sacrificial template. Because of the nanostructure and preferred orientation, it shows a superfast second-level charge capability as a cathode for aqueous rechargeable lithium battery. At the charging rate of 600C (6 s), 53.9% capacity could be obtained. Its reversible capacity can be 110 mAh/g, and it also presents excellent cycling behavior due to the porous tube structure to buffer the strain and stress from Jahn-Teller effects. PMID:23537381

Tang, Wei; Hou, Yuyang; Wang, Faxing; Liu, Lili; Wu, Yuping; Zhu, Kai

2013-04-05

26

Optical constants and polarimetric properties of \\iukcy2-MnO2 thin films  

NASA Astrophysics Data System (ADS)

Optical constants of \\iukcy2-MnO2 (MnO2 content: 0%, 1%, 5%, 10%) thin films prepared by the electron-beam evaporation technique were determined using the envelope method. The optical properties of the TiO2-MnO2 thin films were strongly dependent on the MnO2 content. The TiO2-MnO2 thin films were established to be indirect band semiconductors with the band gap energies Eg: 3.43 eV (TiO2), 2.89 eV (TiO2-MnO2 (1%)) and 2.73 eV (TiO2-MnO2 (5%)). The polarimetric properties of the TiO2-MnO2 thin films were also investigated.

Brus, V. V.; Pidkamin, L. J.; Abashin, S. L.; Kovalyuk, Z. D.; Maryanchuk, P. D.; Chugai, O. M.

2012-09-01

27

MnO 2 multilayer nanosheet clusters evolved from monolayer nanosheets and their predominant electrochemical properties  

Microsoft Academic Search

MnO2 multilayer nanosheet clusters were prepared via electrochemical deposition route, which shows simpleness and high efficiency. The growth process of MnO2 multilayer nanosheet clusters was investigated in this paper. The deposited MnO2 films were characterized by XRD, SEM, TEM, and XPS. In addition, it was also electrochemically characterized by cyclic voltammetry in 1.0M Na2SO4 electrolyte. The MnO2 multilayer nanosheet clusters

Zhan-Ping Feng; Gao-Ren Li; Jin-Hui Zhong; Zi-Long Wang; Yan-Nan Ou; Ye-Xiang Tong

2009-01-01

28

Cobalt dissolution in LiCoO 2-based non-aqueous rechargeable batteries  

Microsoft Academic Search

Rechargeable lithium batteries using a variety of differently prepared LiCoO2 samples were cycled to 4.5 V versus Li and the negative electrode was investigated for Co deposits after the cell was cycled over 25 times. Qualitative analysis revealed evidence of cobalt dissolution for samples showing high capacity loss with cycle number. A direct correlation between the percentage capacity loss and

G. G. Amatucci; J. M. Tarascon; L. C. Klein

1996-01-01

29

The structure and ordering of ?-MnO2  

NASA Astrophysics Data System (ADS)

The presence of ?-MnO2 as a major component of electrolytic manganese dioxide (EMD) has been demonstrated by a combined X-ray diffraction/transmission electron microscopy (TEM) study. ?-MnO2 usually has a partially ordered defect NiAs structure containing 50% cation vacancies; these vacancies can be fully ordered by a low temperature (200 °C) heat treatment to form a pseudohexagonal but monoclinic superlattice. Numerous fine-scale anti-phase domain boundaries are present in ordered ?-MnO2 and cause extensive peak broadening and a massive shift of a very intense, 0.37 nm superlattice peak. This suggests a radically different explanation of the ubiquitous, very broad ˜0.42 nm peak (˜21 22° 2?, CuK? radiation) in EMDs, which heretofore has been attributed to Ramsdellite containing numerous planar defects. This work confirms the multi-phase model of equiaxed EMDs proposed by Heuer et al. [ITE Lett. 1(6) (2000) B50; Proc. Seventh Int. Symp. Adv. Phys. Fields 92 (2001)], rather than the defective single-phase model of Chabre and Pannetier [Prog. Solid State Chem. 23 (1995) 1] and Bowden et al. [ITE Lett. 4(1) (2003) B1].

Kim, Chang-Hoon; Akase, Zentaro; Zhang, Lichun; Heuer, Arthur H.; Newman, Aron E.; Hughes, Paula J.

2006-03-01

30

A critical analysis of cation adsorption from single and binary solutions on low surface area ?-MnO2  

NASA Astrophysics Data System (ADS)

Generally it is advocated that high surface area materials are better adsorbents due to availability of more surface active sites. In the present study, potential of a low surface area (0.81 m2/g) ?-MnO2 has been examined for removal of Pb(II), Cd(II), Cu(II) and Zn(II) ions from aqueous solutions. To understand the adsorption mechanism of cations the various techniques used include SEM, FTIR, XRD and Raman spectroscopy. Inner or outer sphere complex formation was envisaged due to +ve/?ve shifts in FTIR bands. Raman spectra showed shifting of band (red/blue shift) at 636 cm?1 (A1g symmetric mode) for all the cations except Cd(II). Another important observation made was the decrease in scattering intensity of A1g symmetric mode after cation adsorption except for Pb(II) loaded ?-MnO2. This was attributed to the breakdown of long-range translational crystal symmetry caused by the incorporated defects. Results for adsorption on ?-MnO2 from binary solutions namely Pb(II)–Cd(II), Pb(II)–Cu(II), Pb(II)–Zn(II), Cd(II)–Cu(II), Cd(II)–Zn(II) and Cu(II)–Zn(II) are discussed. Pb(II) having a low adsorption capacity of only 26 mg/g showed tenfold increase in presence of Cd(II). The concentration dependent selectivity of certain cations in binary system has been explained on the basis of observed changes in the Raman spectra of loaded ?-MnO2.

Rout, K.; Mohapatra, M.; Anand, S.

2013-04-01

31

Aqueous electrochemistry of poly(vinylanthraquinone) for anode-active materials in high-density and rechargeable polymer/air batteries.  

PubMed

A layer of poly(2-vinylanthraquinone) on current collectors underwent reversible electrode reaction at -0.82 V vs Ag/AgCl in an aqueous electrolyte. A repeatable charging/discharging cycles with a redox capacity comparable to the formula weight-based theoretical density at the negative potential suggested that all of the anthraquinone pendants in the layer was redox-active, that electroneutralization by an electrolyte cation was accomplished throughout the polymer layer, and that the layer stayed on the current collector without exfoliation or dissolution into the electrolyte during the electrolysis. The charging/discharging behavior of the polymer layer in the aqueous electrolyte revealed the capability of undergoing electrochemistry even in the nonsolvent of the pendant group, which offered insight into the nature of the anthraquinone pendants populated on the aliphatic chain. Charging/discharging capability of air batteries was accomplished by using the polymer layer as an organic anode-active material. A test cell fabricated using the conventional MnO(2)/C cathode catalyst exhibited a discharging voltage at 0.63 V corresponding to their potential gap and a charging/discharging cycle of more than 500 cycles without loss of the capacity. PMID:22011047

Choi, Wonsung; Harada, Daisuke; Oyaizu, Kenichi; Nishide, Hiroyuki

2011-11-15

32

Facile Synthesis of Novel Nanostructured MnO2 Thin Films and Their Application in Supercapacitors  

NASA Astrophysics Data System (ADS)

Nanostructured ?-MnO2 thin films with different morphologies are grown on the platinum substrates by a facile solution method without any assistance of template or surfactant. Microstructural characterization reveals that morphology evolution from dandelion-like spheres to nanoflakes of the as-grown MnO2 is controlled by synthesis temperature. The capacitive behavior of the MnO2 thin films with different morphologies are studied by cyclic voltammetry. The ?-MnO2 thin films composed of dandelion-like spheres exhibit high specific capacitance, good rate capability, and excellent long-term cycling stability.

Xia, H.; Xiao, W.; Lai, M. O.; Lu, L.

2009-09-01

33

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

34

Synthesis and characterization of MnO2 colloids  

NASA Astrophysics Data System (ADS)

This work addresses the issue of radiation chemical synthesis of MnO2 nanoparticles and also illustrates the ease of formation of nanorods and sheets by adroit manipulation of experimental conditions. The radiation chemical yield (G-value) for reduction of Mn (VII) by the hydrated electron was found to be 0.27 ?mol J-1 and 0.17 ?mol J-1 respectively, when tert. butanol and isopropanol were used as scavengers in nitrogen-saturated solutions. The colloids formed upon irradiation of air-saturated solution and N2-purged solution with tert. butanol as scavenger were found to be most stable. Irradiation of air-saturated solution containing 4×10-4 M KMnO4 at a dose of 1692 Gy resulted in the formation of nanorods of the dimension 100-150 nm and nanospheres in the range 10-20 nm. Irradiation of N2-purged solution containing tert. butanol as scavenger for OH-produced reticulated structure of nanorods with length varying from 50 to 100 nm at a dose of 1692 Gy. Elemental analysis was performed using scanning electron microscope on MnO2 formed by reduction and oxidation and the purity was found to be 98% of elemental Mn content.

Yadav, Pooja; Olsson, Richard T.; Jonsson, Mats

2009-11-01

35

A hydrogen peroxide sensor based on colloidal MnO 2\\/Na-montmorillonite  

Microsoft Academic Search

A novel amperometric sensor for the determination of hydrogen peroxide was prepared based on the enhanced oxidation of H2O2 at a glassy carbon electrode modified with colloidal MnO2–Na-montmorillonite (nano-MnO2\\/Na-Mont\\/GCE). The montmorillonite has been devised to support and dispense the MnO2 nanoparticles. Scanning electron microscopy images (SEM) showed that the MnO2 nanoparticles were homogeneously dispersed in the colloidal Na-montmorillonite. This colloidal

Shaojun Yao; Shuai Yuan; Junhui Xu; Ying wang; Jianlin Luo; Shengshui Hu

2006-01-01

36

One-pot hydrothermal synthesis of ?-MnO2 crystals and their magnetic properties  

NASA Astrophysics Data System (ADS)

?-MnO2 nanorods and flower-like structures were synthesized via a one-pot hydrothermal route at 160 °C without using any template and surfactant. It is demonstrated that H+ in the solution has a significant effect on the morphology and resultant magnetic property of ?-MnO2 crystals. Magnetic measurements indicate that the Néel temperature of the ?-MnO2 flower-like structures is 98 K, which is about 2 K higher than that of the nanorods counterpart.

Yu, Peng; Zhang, Xiong; Sun, Xianzhong; Wang, Dongliang; Ma, Yanwei

2013-11-01

37

Structural and magnetic properties of orthorhombic Li x MnO 2  

Microsoft Academic Search

Rietveld refinement of the crystal and magnetic structures of LixMnO2 (x=0.98, 1.00, 1.02) are performed using neutron and X-ray measurements. A significant structural disorder due to the presence of manganese ions in lithium positions (MnLi) and lithium ions in manganese ones (LiMn) is found to be a common feature of Li0.98MnO2, Li1.00MnO2, and Li1.02MnO2.An essential anisotropy of the thermal-expansion coefficients

D. G. Kellerman; J. E. Medvedeva; V. S. Gorshkov; A. I. Kurbakov; V. G. Zubkov; A. P. Tyutyunnik; V. A. Trunov

2007-01-01

38

Controllable synthesis of MnO2/polyaniline nanocomposite and its electrochemical capacitive property  

PubMed Central

Polyaniline (PANI) and MnO2/PANI composites are simply fabricated by one-step interfacial polymerization. The morphologies and components of MnO2/PANI composites are modulated by changing the pH of the solution. Formation procedure and capacitive property of the products are investigated by XRD, FTIR, TEM, and electrochemical techniques. We demonstrate that MnO2 as an intermedia material plays a key role in the formation of sample structures. The MnO2/PANI composites exhibit good cycling stability as well as a high capacitance close to 207 F?g?1. Samples fabricated with the facile one-step method are also expected to be adopted in other field such as catalysis, lithium ion battery, and biosensor.

2013-01-01

39

Controllable synthesis of MnO2/polyaniline nanocomposite and its electrochemical capacitive property  

NASA Astrophysics Data System (ADS)

Polyaniline (PANI) and MnO2/PANI composites are simply fabricated by one-step interfacial polymerization. The morphologies and components of MnO2/PANI composites are modulated by changing the pH of the solution. Formation procedure and capacitive property of the products are investigated by XRD, FTIR, TEM, and electrochemical techniques. We demonstrate that MnO2 as an intermedia material plays a key role in the formation of sample structures. The MnO2/PANI composites exhibit good cycling stability as well as a high capacitance close to 207 F g-1. Samples fabricated with the facile one-step method are also expected to be adopted in other field such as catalysis, lithium ion battery, and biosensor.

Meng, Fanhui; Yan, Xiuling; Zhu, Ye; Si, Pengchao

2013-04-01

40

Growth and magnetic properties of MnO2-? nanowire microspheres  

NASA Astrophysics Data System (ADS)

We report the synthesis of MnO2-? microspheres using hydrothermal and conventional chemical reaction methods. The microspheres of MnO2-? consist of nanowires having a diameter of 20-50 nm and a length of 2-8 ?m. The value of oxygen vacancy ? estimated from x-ray photoelectron spectrum is 0.3. The magnetization versus temperature curve indicates a magnetic transition at about 13 K. It is found that a parasitic ferromagnetic component is imposed on the antiferromagnetic structure of MnO2-?, which might result from distortion of the lattice structure due to oxygen vacancies. The magnetic transition temperature TN is about 10 K lower than that of the bulk MnO2 single crystal.

Yang, J. B.; Zhou, X. D.; James, W. J.; Malik, S. K.; Wang, C. S.

2004-10-01

41

Electrochemical properties of air electrodes based on MnO 2 catalysts supported on binary carbons  

Microsoft Academic Search

An alkaline air electrode with a ball-milled ?-MnO2 catalyst was prepared and studied. The electrochemical performance of air electrode composed of MnO2 supported on CNT\\/BP2000 (1:1) two carbons for oxygen reduction reaction (ORR) was investigated by using the linear polarization method, Tafel analysis, galvanostatic discharge method, and AC impedance spectroscopy. The surface morphologies of CNT and the active layer of

Chun-Chen Yang; Sung-Ting Hsu; Wen-Chen Chien; Ming Chang Shih; Shwu-Jer Chiu; Kuo-Tong Lee; Ching Li Wang

2006-01-01

42

Effects of MnO2 Nanoparticles on Liver and Kidney Cells of Rats  

Microsoft Academic Search

In order to study the effects of MnO2 nanoparticles on cells of rats liver and kidney, rats liver and kidney cells were exposed to different concentrations (0, 0.05, 0.50, 5.00, 50.00 ?g\\/mL) of MnO2 nanoparticles at 37?. An hour later, reactive oxygen species (ROS) levels, glutathione (GSH) concentrations and DNA-protein crosslinks (DPC) degrees in cells were measured to detect the

Huihui You; Jingyun Zhao; Lingling Li; Junlin Yuan

2011-01-01

43

?-MnO2 nanotubes: high surface area and enhanced lithium battery properties.  

PubMed

A simple one-step route for preparing ?-MnO(2) nanotubes is reported. The ?-MnO(2) nanotubes exhibit a high surface area of 226 m(2) g(-1) and reversible capacity of 512 mA h g(-1) at a high current density of 800 mA g(-1) after 300 cycles, as well as cycling stability when measured as an anode in lithium batteries. PMID:22674121

Li, Lihong; Nan, Caiyun; Lu, Jun; Peng, Qing; Li, Yadong

2012-06-07

44

Synthesis and study of ?-MnO 2 supported Pt nanocatalyst for methanol electro-oxidation  

Microsoft Academic Search

A ?-MnO2 supported Pt nanocatalyst (5 wt.% Pt\\/?-MnO2) was synthesized using a facile approach. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electronic\\u000a microscope (SEM), transmission electron microscopy (TEM), and energy disperse spectroscopy (EDS) were used for catalyst structure\\u000a and morphology characterization, which showed that the metallic Pt particles were attached on a ?-MnO2 surface through the interaction between Pt

Jia Xie; Xiang Li; Zhihui Yu; Lijuan Zhang; Fan Li; Dingguo Xia

2010-01-01

45

Long term effect of MnO2 powder addition on nitrogen removal by anammox process.  

PubMed

This study examined long-term effect of MnO(2) powder (average diameter of 4-7 ?m) on nitrogen removal in anammox process. Two lab-scale up-flow anammox reactors were operated for 380 days, one with and one without MnO(2) powder addition. During the period when only substrate concentrations varied, the maximum nitrogen removal rate in the reactor with MnO(2) addition reached 920.9 g-N/m(3)/d. This value was 2-folds higher than that (464.6 g-N/m(3)/d) of the reactor without MnO(2) addition. The crude enzyme activities of the anammox biomass from the two reactors was measured as 0.531±0.019 and 0.298±0.007 ?mol cytochrome c reduced/mg protein/min, respectively. Transmission electron microscopy observation demonstrated more undefined particles existing inside anammox bacterial cell in the reactor with MnO(2) powder addition. Furthermore, filament-like structures inside anammoxosome were observed, which formed a net-like structure with particles as the connecting nodes. The experiment results demonstrated that MnO(2) improved nitrogen removal performance of anammox process. PMID:23036909

Qiao, Sen; Bi, Zhen; Zhou, Jiti; Cheng, Yingjun; Zhang, Jie; Bhatti, Zafar

2012-08-07

46

Bacterial dissimilatory MnO(2) reduction at extremely haloalkaline conditions.  

PubMed

A possibility of dissimilatory MnO(2) reduction at extremely high salt and pH was studied in sediments from hypersaline alkaline lakes in Kulunda Steppe (Altai, Russia). Experiments with anaerobic sediment slurries demonstrated a relatively rapid reduction of colloidal MnO(2) in the presence of acetate and formate as electron donor at in situ conditions (i.e., pH 10 and a salt content from 0.6 to 4 M total Na(+)). All reduced Mn at these conditions remained in the solid phase. A single, stable enrichment culture was obtained from the slurries consistently reducing MnO(2) at pH 10 and 0.6 M total Na(+) with formate. A pure culture of a haloalkaliphilic Mn-reducing bacterium obtained from the positive enrichment was phylogenetically closely related to the anaerobic haloalkaliphilic Bacillus arseniciselenatis isolated from Mono Lake (CA, USA). Bacillus sp. strain AMnr1 was obligately anaerobic, able to grow either by glucose fermentation, or respiring few nonfermentable substrates by using MnO(2) as the electron acceptor. Optimal growth by dissimilatory MnO(2) reduction was achieved with glycerol as electron donor at pH 9.5-10 and salt content between 0.4 and 0.8 M total Na(+). PMID:19779762

Sorokin, Dimitri Yu; Muyzer, G

2009-09-25

47

Electrochemical oxidation of methanol on Pt nanoparticles composited MnO 2 nanowire arrayed electrode  

NASA Astrophysics Data System (ADS)

By use of the membrane-template synthesis route, MnO 2 nanowire arrayed electrodes are successfully synthesized by means of the anodic deposition technique. The Pt nanoparticles composited MnO 2 nanowire arrayed electrodes (PME) are obtained through depositing Pt on MnO 2 nanowire arrayed electrode by cathode deposition technique. For comparison of electrochemical performance, Pt nanowire arrayed electrodes which have the same amount of Pt with PME are also prepared. The electro-oxidation of methanol on PME and Pt nanowire arrayed electrodes is investigated at room temperature by cyclic voltammetry, which show that about 110 mV decreased overpotential and 2.1-fold enhanced votammetric current are achieved on PME. The chronoamperometry result demonstrates that the resistance to carbon monoxide for PME is improved.

Zhao, Guang-Yu; Li, Hu-Lin

2008-03-01

48

Coaxial MnO2/carbon nanotube array electrodes for high-performance lithium batteries.  

PubMed

Coaxial manganese oxide/carbon nanotube (CNT) arrays deposited inside porous alumina templates were used as cathodes in a lithium battery. Excellent cyclic stability and capacity of MnO2/CNT coaxial nanotube electrodes resulted from the hybrid nature of the electrodes with improved electronic conductivity and dual mechanism of lithium storage. The reversible capacity of the battery was increased by an order compared to template grown MnO2 nanotubes, making them suitable electrodes for advanced Li ion batteries. PMID:19186940

Reddy, Arava Leela Mohana; Shaijumon, Manikoth M; Gowda, Sanketh R; Ajayan, Pulickel M

2009-03-01

49

Some restatements on the nature and behavior of MnO2 for Li batteries  

NASA Astrophysics Data System (ADS)

A reconsideration of aspects of the behavior of MnO2 as a cathode for nonaqueous Li cells shows that this compound's most active form is obtained by heating electrolytic MnO2 in the 350-400 C range. It is determined that, in the disordered orthorhombic structure of electrochemical gamma-MnO2, Li(+) is topochemically incorporated. This process causes structural alterations at relatively low Li(+) contents, and the flat discharge curves obtained suggest the formation of a pseudo-two-phase compound. Reversibility is incomplete because of these features, and is exhibited only in mild conditions.

Pistoia, G.

1982-09-01

50

Facile preparation of single-crystalline nanowires of ?MnOOH and ?MnO2  

NASA Astrophysics Data System (ADS)

A facile method has been developed to synthesize single-crystalline manganese (oxyhydr)oxide nanowires. A pure phase of single-crystalline ?MnOOH nanowires with the lengths of several hundred nanometres to several micrometers and the diameters of 5 40 nm was synthesized by hydrothermal transformation of commercial granular ?- or ?MnO2 in water, and single-crystalline ?MnO2 and polycrystalline ?Mn2O3 nanowires formed after subsequent calcination at 300 and 600 °C of the as-prepared ?MnOOH nanostructures, respectively. These low-dimensional nanostructured materials may find novel properties and provide more possible applications in lithium batteries and catalysis.

Yuan, Z.-Y.; Ren, T.-Z.; Du, G.-H.; Su, B.-L.

2005-02-01

51

Binding of Colloidal MnO2 by Extracellular Polysaccharides of Pedomicrobium manganicum  

PubMed Central

The extracellular acidic polysaccharides of the manganese-oxidizing bacterium Pedomicrobium manganicum were able to bind preformed colloidal MnO2. The capacity of the cells to bind MnO2 was pH dependent. Enhanced binding capacity below pH 5 suggests that ionic bonding forces are involved in the binding mechanism and that there is a charge reversal on the acidic polysaccharides between pH 5 and 4 that is due to increased protonation of carboxyl groups. Images

Sly, L. I.; Arunpairojana, Vullapa; Dixon, D. R.

1990-01-01

52

3D MnO2-graphene composites with large areal capacitance for high-performance asymmetric supercapacitors  

NASA Astrophysics Data System (ADS)

In this paper, we reported an effective and simple strategy to prepare large areal mass loading of MnO2 on porous graphene gel/Ni foam (denoted as MnO2/G-gel/NF) for supercapacitors (SCs). The MnO2/G-gel/NF (MnO2 mass: 13.6 mg cm-2) delivered a large areal capacitance of 3.18 F cm-2 (234.2 F g-1) and good rate capability. The prominent electrochemical properties of MnO2/G-gel/NF are attributed to the enhanced conductivities and improved accessible area for ions in electrolytes. Moreover, an asymmetric supercapacitor (ASC) based on MnO2/G-gel/NF (MnO2 mass: 6.1 mg cm-2) as the positive electrode and G-gel/NF as the negative electrode achieved a remarkable energy density of 0.72 mW h cm-3. Additionally, the fabricated ASC device also exhibited excellent cycling stability, with less than 1.5% decay after 10 000 cycles. The ability to effectively develop SC electrodes with high mass loading should open up new opportunities for SCs with high areal capacitance and high energy density.In this paper, we reported an effective and simple strategy to prepare large areal mass loading of MnO2 on porous graphene gel/Ni foam (denoted as MnO2/G-gel/NF) for supercapacitors (SCs). The MnO2/G-gel/NF (MnO2 mass: 13.6 mg cm-2) delivered a large areal capacitance of 3.18 F cm-2 (234.2 F g-1) and good rate capability. The prominent electrochemical properties of MnO2/G-gel/NF are attributed to the enhanced conductivities and improved accessible area for ions in electrolytes. Moreover, an asymmetric supercapacitor (ASC) based on MnO2/G-gel/NF (MnO2 mass: 6.1 mg cm-2) as the positive electrode and G-gel/NF as the negative electrode achieved a remarkable energy density of 0.72 mW h cm-3. Additionally, the fabricated ASC device also exhibited excellent cycling stability, with less than 1.5% decay after 10 000 cycles. The ability to effectively develop SC electrodes with high mass loading should open up new opportunities for SCs with high areal capacitance and high energy density. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr01589k

Zhai, Teng; Wang, Fuxin; Yu, Minghao; Xie, Shilei; Liang, Chaolun; Li, Cheng; Xiao, Fangming; Tang, Renheng; Wu, Qixiu; Lu, Xihong; Tong, Yexiang

2013-07-01

53

Redox exchange induced MnO2 nanoparticle enrichment in poly(3,4-ethylenedioxythiophene) nanowires for electrochemical energy storage.  

PubMed

MnO2 nanoparticle enriched poly(3,4-ethylenedioxythiophene) (PEDOT) nanowires are fabricated by simply soaking the PEDOT nanowires in potassium permanganate (KMnO4) solution. The structures of these MnO2 nanoparticle enriched PEDOT nanowires are characterized by SEM and TEM, which show that the MnO2 nanoparticles have uniform sizes and are finely dispersed in the PEDOT matrix. The chemical constituents and bonding of these composite nanowires are characterized by energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy, and infrared spectroscopy, which indicate that the formation and dispersion of these MnO2 nanoparticles into the nanoscale pores of the PEDOT nanowires are most likely triggered by the reduction of KMnO4 via the redox exchange of permanganate ions with the functional group on PEDOT. Varying the concentrations of KMnO4 and the reaction time controls the loading amount and size of the MnO2 nanoparticles. Cyclic voltammetry and galvanostatic charge-discharge are used to characterize the electrochemical properties of these MnO2 nanoparticle loaded PEDOT nanowires. Due to their extremely high exposed surface area with nanosizes, the pristine MnO2 nanoparticles in these MnO2 nanoparticle enriched PEDOT nanowires show very high specific capacitance (410 F/g) as the supercapacitor electrode materials as well as high Li+ storage capacity (300 mAh/g) as cathode materials of Li ion battery, which boost the energy storage capacity of PEDOT nanowires to 4 times without causing excessive volume expansion in the polymer. The highly conductive and porous PEDOT matrix facilitates fast charge/discharge of the MnO2 nanoparticles and prevents them from agglomerating. These synergic properties enable the MnO2 nanoparticle enriched PEDOT nanowires to be promising electrode materials for supercapacitors and lithium ion batteries. PMID:20590128

Liu, Ran; Duay, Jonathon; Lee, Sang Bok

2010-07-27

54

High aspect ratio ?-MnO2 nanowires and sensor performance for explosive gases  

NASA Astrophysics Data System (ADS)

High aspect ratio ?-MnO2 nanowires have been synthesized based on a facile and green technique without any chemical additive. The precursor solution of Mn3O4 nanocrystals was first synthesized by laser ablation of a manganese target in deionized water. Due to the high reactive and fresh surface of Mn3O4 nanocrystals produced by laser ablation in liquid, these nanocrystals were spontaneously assembled into the ?-MnOOH nanowires in the precursor solution after aging at room temperature. The high aspect ratio ?-MnO2 nanowires were finally produced by the ?-MnOOH nanowires annealing at 300 °C for 3 h. For the high aspect ratio ?-MnO2 nanowires, the high specific surface area is advantaged for gas absorption and the unique tunnel structure is good for gas molecule trapping. A gas sensor was made from the ?-MnO2 nanowires for explosive gases. The investigations were carried out for the detection of various concentration of H2 at different temperatures, and the results demonstrated that the fabricated gas sensor can detect H2 down to 20 ppm with the sensitivity of 0.5 at 300 °C and short response time of 10s. For sensing CO and ethanol, the detecting concentration reached to 20 ppm at an operation temperature of 150 and 250 °C, respectively. These results can be comparable to that of the current advanced gas sensors made from metal oxide such as ZnO and SnO2, which showing that high aspect ratio ?-MnO2 nanowires can be regarded as desirable candidate materials for fabricating gas sensors.

Xiao, J.; Liu, P.; Liang, Y.; Li, H. B.; Yang, G. W.

2013-08-01

55

?-MnO2 as a cathode material for lithium ion batteries from first principles calculations.  

PubMed

The search for excellent cathodes for lithium batteries is the main topic in order to meet the requirements of low cost, high safety, and high capacity in many real applications. ?-MnO2, as a potential candidate, has attracted great attention because of its high stability and potential high capacity among all the phases. Because of the complexity of ?-MnO2, some fundamental questions at the atomic level during the charge-discharge process, remain unclear. The lithiation process of ?-MnO2 has been systematically examined by first-principles calculations along with cluster expansion techniques. Five stable configurations during the lithium intercalation process are firstly determined, and the electrochemical voltages are from 3.47 to 2.77 eV, indicating the strongly correlated effects of the ?-MnO2-LiMnO2 system. During the lithiation process, the changes in the lattice parameters are not symmetric. The analysis of electronic structures shows that Mn ions are in the mixed valence states of Mn(3+) and Mn(4+) during the lithiation process, which results in Jahn-Teller distortion in Mn(3+)O6 octahedra. Such results uncover the intrinsic origin of the asymmetric deformation during the charge-discharge process, resulting in the irreversible capacity fading during cycling. From the analysis of the thermal reduction of delithiated LixMnO2, the formation of oxygen is thermodynamically infeasible in the whole extraction process. Our results indicate that ?-MnO2 has great potential as a cathode material for high capacity Li-ion batteries. PMID:23646354

Wang, Da; Liu, Li-Min; Zhao, Shi-Jin; Li, Bai-Hai; Liu, Hao; Lang, Xiu-Feng

2013-05-03

56

Nanoporous LiNi1/3Co1/3Mn1/3O2 as an ultra-fast charge cathode material for aqueous rechargeable lithium batteries.  

PubMed

Nanoporous LiNi1/3Co1/3Mn1/3O2 (NP-NCM) was synthesized by using vapour grown carbon fibers (VGCFs) as templates. It exhibits excellent electrochemical performance as a cathode material for aqueous rechargeable lithium batteries, especially with ultra-fast charge capability, and 72 mA h g(-1) can be achieved at a charge time of 20 s. PMID:23998182

Wang, Faxing; Xiao, Shiying; Chang, Zheng; Yang, Yaqiong; Wu, Yuping

2013-08-30

57

MnO2 nanotube-Pt/graphene mixture as an ORR catalyst for proton exchange membrane fuel cell  

NASA Astrophysics Data System (ADS)

In the present study, MnO2 nanotubes are synthesized by hydrothermal method and Pt/graphene by co reduction of hexachloroplatinic acid and graphite oxide. The formation of MnO2 nanotubes and Pt/graphene are confirmed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy. MnO2 nanotubes are mixed with Pt/graphene is applied as the ORR catalyst in proton exchange membrane fuel cell. The single cell measurement is carried out after fabricating the membrane electrode assembly and polarization curves are recorded at different temperatures and the results are discussed.

Divya, P.; Ramaprabhu, S.

2013-02-01

58

Hybrid MnO2 Film with Agarose Gel for Enhancing the Structural Integrity of Thin Film Supercapacitor Electrodes.  

PubMed

We report on the fabrication of a robust hybrid film containing MnO2 for achieving large areal capacitances. An agarose gel, as an ion-permeable and elastic layer coated on a current collector, plays a key role in stabilizing the deposited pseudocapacitive MnO2. Cyclic voltammetry and electrochemical impedance spectroscopy data indicate that the hybrid electrode is capable of exhibiting a high areal capacitance up to 52.55 mF cm(-2), with its superior structural integrity and adhesiveness to the current collector being maintained, even at a high MnO2 loading. PMID:24080145

Park, Soomin; Nam, Inho; Kim, Gil-Pyo; Han, Jeong Woo; Yi, Jongheop

2013-10-03

59

Magnetic properties of glass ceramic in Fe3O4-MnO2-SiO2 system  

NASA Astrophysics Data System (ADS)

The magnetic glass-ceramics was prepared by a melt-quenching method with the phase-separated melts in two-liquids stable immiscibility region of Fe3O4-MnO2-SiO2 system. The obtained glass-ceramics had spinel single phase of Fe3O4-MnO2 solid solution, and showed ferromagnetic properties. The saturated magnetization became a maximum by adding a small amount of MnO2 with low coercive force. These properties of both high magnetization and low coercive force by Mn doping are very effective to realize the magnetic materials for the hyperthermia treatment.

Abe, Takayuki; Kisi, Tetsuo; Yasumori, Atsuo

2010-06-01

60

Magnetic properties of glass ceramic in Fe3O4-MnO2SiO2 system  

Microsoft Academic Search

The magnetic glass-ceramics was prepared by a melt-quenching method with the phase-separated melts in two-liquids stable immiscibility region of Fe3O4-MnO2-SiO2 system. The obtained glass-ceramics had spinel single phase of Fe3O4-MnO2 solid solution, and showed ferromagnetic properties. The saturated magnetization became a maximum by adding a small amount of MnO2 with low coercive force. These properties of both high magnetization and

Takayuki Abe; Tetsuo Kisi; Atsuo Yasumori

2010-01-01

61

NO x adsorption on MnO 2\\/NaY composite: an in situ FTIR and EPR study  

Microsoft Academic Search

The NO, NO\\/O2, and NO\\/O2\\/H2O adsorption on MnO2\\/NaY (5 and 15wt.% MnO2) composite catalyst and NaY has been studied by means of in situ FTIR and EPR spectroscopy at elevated temperatures and during heating under reaction-like conditions. NO adsorption and co-adsorption of NO and O2 on NaY and MnO2\\/NaY proceeds via oxidation of NO forming NO2? and NO3? species. Whereas

Ursula Bentrup; Angelika Brückner; Manfred Richter; Rolf Fricke

2001-01-01

62

Effects of MnO2 Addition on the Dielectric Behaviors of the PZT-PMN Ceramics  

Microsoft Academic Search

The PZT-PMN ceramics system proposed for piezoelectric transformation application was derived from Pb(Zr0.52Ti0.48)O3 and Pb(Mg0.66Nb0.33)O3 based compositions that obtained from the culombite method. The effect of MnO2 addition on microstructure, physical properties and piezoelectric properties were investigated. The XRD results show that no phase transformation observed for all sintered PZT-PMN samples doped with MnO2. Presence of MnO2 also improved their

R. Tipakontitikul; Y. Suwan; A. Niyompan

2009-01-01

63

IMPROVED ESR ON MnO2 TANTALUM CAPACITORS AT WIDE VOLTAGE RANGE  

Microsoft Academic Search

One common trend in switch-mode power supply, micro-processor, and digital circuit applications is to achieve reduced noise while operating at higher frequencies. In order realize this, components with low Equivalent Series Resistance (ESR), high capacitance and high reliability are required. A new generation of Low ESR tantalum chip capacitors has been developed utilizing a low resistivity MnO2 electrolyte that enables

I. Horacek; T. Zednicek; M. Komarek; J. Tomasko; S. Zednicek; W. A. Millman; J. Sikula; J. Hlavka

64

Two-Dimensionally Confined Water in between MnO2 Layers of Na-Birnessite  

NASA Astrophysics Data System (ADS)

Two-dimensionally confined water in between the MnO2 octahedral layers in Na-birnessite has been studied to clarify the physical properties and the structural arrangements. From the analysis employing an inductively coupled plasma (ICP) method and chemical titration, the chemical composition is determined to be Na0.28Mn4+0.73Mn3+0.27O2 yH2O in our sample. According to the X-ray diffraction (XRD) experiments, the interlayer distance along the c axis is 7.17 Å at 293 K in atmosphere, though the distance shrinks to 5.77 Å when the sample is kept either at 333 K in atmosphere or at 293 K in vacuum. The weight loss obtained by thermogravimetry exhibits two steps caused by the dehydration in atmosphere. Together with the XRD data, we confirm that there are two contributions of the water in the interlayers; weakly hydrated water and strongly hydrated water. The latter is regarded as a structural water to maintain the layer structure. In the infrared spectra, three novel peaks are found to develop in evacuating the sample. These peaks are associated with three different distances in between oxygen atoms of water molecules identified by the precise X-ray studies so far. We consider that Na+ ion locates approximately at one MnO2 unit with Mn3+ among the four MnO2 units to preserve charge valence, and the strongly hydrated water molecules surround Na+ in the form of a quasi-planer hexamer-like cluster reflecting the symmetry of MnO2 layer. The strict restriction of water to the plane and the Coulomb repulsion between Na+ may induce a deformation of the cluster leading to the abovementioned three different distances.

Matsui, Hiroshi; Ju, Jing; Odaira, Tomohiro; Toyota, Naoki

2009-07-01

65

Evolving microstructure in MnO2 using amorphisation and recrystallisation  

NASA Astrophysics Data System (ADS)

The electrochemical properties of ?-MnO2 are governed by the rich and complex microstructure it accommodates. However, characterisation, at the atomistic level, of this material is difficult experimentally; rather the materials are typified by their X-ray diffraction (XRD) patterns. Here, we use an evolutionary simulation—amorphisation and recrystallisation (A&R)—to generate atomistic models for ?-MnO2, which include microstructural detail. These models conform to the pyrolusite polymorph, with small intergrowth domains (structurally similar to brookite-TiO2) and comprise micro-twinning together with general grain boundaries, stacking faults, dislocations and isolated point defects and defect clusters. Molecular graphics images, showing the atom positions for these microstructural features together with the (simulated) XRD patterns they give rise to, are presented and compare favourably with measured XRD providing valuable validation of the atomistic models. Surprisingly, the atomistic models also include anion sublattice domains conforming to both ccp and hcp, which are separated or facilitated by dislocations. We are not aware of this phenomenon having been reported in the literature for MnO2 and therefore, our simulations offer the prediction of its existence.

Sayle, Thi X. T.; Catlow, C. Richard A.; Maphanga, R. Rapella.; Ngoepe, Phuti E.; Sayle, Dean C.

2006-08-01

66

A highly sensitive hydrogen peroxide amperometric sensor based on MnO 2 nanoparticles and dihexadecyl hydrogen phosphate composite film  

Microsoft Academic Search

A sensitive sensor for the determination of hydrogen peroxide (H2O2) was fabricated with MnO2 nanoparticles (nano-MnO2) and dihexadecyl hydrogen phosphate (DHP) composite film. The sensor exhibits high sensitivity, due to the enhanced oxidation of hydrogen peroxide (H2O2) at the MnO2 nanoparticles and its uniform dispersion in DHP film. Amperometry was carried to determine the concentration of H2O2. The dependence of

Shaojun Yao; Junhui Xu; Ying Wang; Xiaoxia Chen; Yanxia Xu; Shengshui Hu

2006-01-01

67

Carbon nanohorns as a high-performance carrier for MnO2 anode in lithium-ion batteries.  

PubMed

MnO(2) nanoflakes coated on carbon nanohorns (CNHs) has been synthesized via a facile solution method and evaluated as anode for lithium-ion batteries. By using CNHs as buffer carrier, MnO(2)/CNH composite displays an excellent capacity of 565 mA h/g measured at a high current density of 450 mA/g after 60 cylces. PMID:22545767

Lai, Heng; Li, Jiaxin; Chen, Zhigao; Huang, Zhigao

2012-05-02

68

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.

69

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

70

Distribution of elements in the surface layer of plasma-electrolytic coatings formed on titanium in electrolytes with MnO2 particles  

NASA Astrophysics Data System (ADS)

The influence of electrolytes (aqueous solutions of H2SO4, Na2SO3, and K2B4O7 (group I) and Na2SiO3 (group II)), as well as the effects of pores and ridges around them, on the element composition of oxide coatings was studied. The addition of MnO2 particles to electrolytes initiated the formation of large pores. The pores had increased titanium and decreased oxygen contents. Coatings I contained, on average, up to 1 at % Mn, and coatings II had up to 8 at % Mn; in the pores of II, the Mn concentration was increased to 18 at %. The coatings contained 7-28 at % carbon, which was concentrated in pores in I and on the surface of the oxide coating in II.

Rudnev, V. S.; Vasilyeva, M. S.; Nedozorov, P. M.; Korotenko, I. A.; Vaganov-Vil'Kins, A. A.

2011-10-01

71

New lithium-manganese composite oxide for the cathode of rechargeable lithium batteries  

Microsoft Academic Search

A LiNO3-MnO2 mixture, heat treated in the presence of H2O2 or HNO3, has shown excellent rechargeability as an electrode material for rechargeable lithium batteries. XRD patterns of this compound are completely different from known Li-Mn composite oxides such as LiMn2O4 or Li2MnO3. The presence of H2O2 or HNO3 preferentially reduces the LiMn2O4 content. The physicochemical properties of this new compound

M. Yoshio; S. Inoue; M. Hyakutake; G. Piao; H. Nakamura

1991-01-01

72

Hierarchical MnO2/SnO2 Heterostructures for a Novel Free-Standing Ternary Thermite Membrane.  

PubMed

We report the synthesis of a novel hierarchical MnO2/SnO2 heterostructures via a hydrothermal method. Secondary SnO2 nanostructure grows epitaxially on the surface of MnO2 backbones without any surfactant, which relies on the minimization of surface energy and interfacial lattice mismatch. Detailed investigations reveal that the cover density and morphology of the SnO2 nanostructure can be tailored by changing the experimental parameter. Moreover, we demonstrate a bottom-up method to produce energetic nanocomposites by assembling nanoaluminum (n-Al) and MnO2/SnO2 hierarchical nanostructures into a free-standing MnO2/SnO2/n-Al ternary thermite membrane. This assembled approach can significantly reduce diffusion distances and increase their intimacy between the components. Different thermite mixtures were investigated to evaluate the corresponding activation energies using DSC techniques. The energy performance of the ternary thermite membrane can be manipulated through different components of the MnO2/SnO2 heterostructures. Overall, our work may open a new route for new energetic materials. PMID:23905515

Yang, Yong; Zhang, Zhi-Cheng; Wang, Peng-Peng; Zhang, Jing-Chao; Nosheen, Farhat; Zhuang, Jing; Wang, Xun

2013-08-01

73

Effects on the postnatal development of the mouse of preconception, postconception and/or suckling exposure to manganese via maternal inhalation exposure to MnO2 dust.  

PubMed

Female mice were exposed either to MnO2 dust (7 hours/day, 5 days/week) or filtered air (control group) for 16 weeks prior to conception. On day 1 of gestation, half of each of these groups was assigned randomly either to MnO2 dust or filtered air exposure until day 17 of gestation. To separate effects of prenatal maternal exposure to MnO2 from postnatal exposure of offspring to Mn via suckling, a complete fostering/-cross-fostering design was employed. Compared to control mothers, mothers exposed to MnO2 prior to conception produced significantly larger litters. Prenatal exposure resulted in reduced neonatal activity scores and retarded offspring growth that persisted into adulthood. Offspring reared by mothers exposed to MnO2 prior to conception and filtered air postconception had significantly lower day 7 postpartum weights compared to offspring reared by mothers exposed to filtered air both prior to and postconception. Also, offspring reared by mothers exposed to MnO2 prior to conception and filtered air postconception had higher day 12 activity scores compared to offspring reared by mothers exposed to filtered air prior to conception and MnO2 postconception. Prenatal exposure to MnO2 depressed neonate activity and continued exposure, via suckling, intensified this depression. Offspring exposed prenatally to MnO2 were retrieved faster than control offspring. Rearing frequency, exploratory behavior, and scores in tests having an activity component were depressed for sexually mature offspring who had been exposed to MnO2 both in utero and via suckling. Independent of in utero exposure history, sexually mature offspring reared by mothers exposed to Mn had significantly reduced cerebellum + brain stem mitochondrial Mn levels. Also, sexually mature offspring of mothers exposed to filtered air that were reared by MnO2 -exposed mothers had lower cerebral mitochondrial Mn levels than offspring of control mothers reared by control foster mothers. PMID:6538947

Lown, B A; Morganti, J B; D'Agostino, R; Stineman, C H; Massaro, E J

1984-01-01

74

2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)-Catalyzed Reactions Employing MnO2 as a Stoichiometric Oxidant  

PubMed Central

Several oxidative reactions can be effected with MnO2 in the presence of sub-stoichiometric quantities of DDQ. These transformations include oxidative cyclization, deprotection, and dehydrogenation reactions. The use of MnO2 as a terminal oxidant for DDQ-mediated reactions is attractive based on economical and environmental factors.

Liu, Lei; Floreancig, Paul E.

2010-01-01

75

Composite MnO2-Carbon Electrodes for High Energy Density Storage  

NASA Astrophysics Data System (ADS)

The development of batteries with ever higher power densities is challenged by fundamental materials limitations that might be solved with hybrid combinations of materials. For example, metal oxides with high lithium ion capacities lack the conductivity to be good battery anodes, but composites that add graphitic carbon can achieve both capacity and conductivity. In this case, fast interfacial electron transfer between the materials is critical to achieving high performance. Here, we describe an electrochemical synthesis that achieves precise, conformal MnO2 films on graphitic surfaces. Furthermore, by using single-walled nanotubes as the carbon support, we can control defect densities with single defect resolution. Charge-discharge cycling of these electrodes, combined with control over point defects, directly distinguishes the enhanced charge transfer of defects and illuminates the structure-function relationship in interfacial electron transfer. This research is supported by the NEES Energy Frontier Research Center of the U.S. DOE Office of Basic Energy Sciences (#DESC0001160).

Corso, Brad; Perez, Israel; Collins, Philip

2011-03-01

76

Stable Isotope Fractionation during Chromium(III) Oxidation by ?-MnO2  

NASA Astrophysics Data System (ADS)

Hexavalent chromium is a highly mobile anthropogenic pollutant, and reduction of Cr(VI) to the less-soluble Cr(III) is the most important natural process involved in contamination attenuation. Earlier work has shown a preferential reduction of lighter Cr stable isotopes attributed to a kinetically-controlled mechanism, and isotope ratio measurements may be used as indicators of Cr(VI) reduction [1]. Recent work has detected no significant isotope exchange between dissolved Cr(III) and Cr(VI) over a period of days to weeks, and has suggested that complex bidirectional reactions control fractionation during Cr(III) oxidation by H2O2 [2]. Previous studies on oxidation by pyrolusite (?-MnO2) have reported ?53/52Cr up to approximately +1.1‰ in the Cr(VI) product [3]. However, laboratory investigations of fractionation during Cr(III) oxidation by birnessite (?-MnO2) have been inconclusive, and oxidation mechanisms remain unclear [4]. In order to fully exploit stable isotope fractionation during redox reactions of Cr in groundwater as an indicator of Cr attenuation, the effect of Cr(III) oxidation on isotope ratios must be better understood. We will report the latest measurements of isotope fractionation during oxidation on birnessite under varying pH and MnO2 and Cr(III) concentrations. Our preliminary findings (at initial Cr(III) and ?-MnO2 concentrations of 10 mg/L and 100 mg/L, respectively) show the Cr(VI) product shifted by -0.5‰ to +0.0‰ relative to the reactant at pH ? 4.5. The reaction is incomplete and plateaus within 60 min. Unlike that observed with pyrolusite, fractionation during Cr oxidation on birnessite is much smaller or absent. These initial results suggest that kinetic effects are either very small or are negated by back reaction or equilibration in the multi-step oxidation mechanism. Alternatively, in our experiments, a step involving little isotope fractionation may be rate-limiting; thus, the final magnitude of isotope fractionation during oxidation on birnessite could vary if the rate-limiting step changes. Additional experiments at different conditions will aid in the elucidation of fractionating mechanisms during Cr(III) oxidation. [1] Ellis, A. S.; Johnson, T. M.; Bullen, T. D. (2002) Science, 295(5562), 2060 [2] Zink, S.; Schoenberg, R.; Staubwasser, M. (2010) Geochim. Cosmochim. Acta, in press [3] Ellis, A. S.; Johnson, T. M.; Villalobos-Aragon, A.; Bullen, T. D. (2008) Eos Trans. AGU, 89(53), Fall Meet. Suppl., Abstract H53F-08 [4] Bain, D. J.; Bullen, T. D. (2005) Geochim. Cosmochim. Acta, 69(10), Suppl. 1, A212

Wang, D. T.; Fregoso, D. C.; Ellis, A. S.; Johnson, T. M.; Bullen, T. D.

2010-12-01

77

Fabrication and Hydrogen Storage Property of Mg-3Ni-2MnO2-nCNTS Nanocomposites  

NASA Astrophysics Data System (ADS)

Mg-3Ni-2MnO2 hydrogen storage nanocomposites added with different composition (1%~4%) carbon nanotubes (CNTs) were prepared by mechanical milling under the atmosphere of hydrogen. Different mechanical milling process parameter has been discussed in this paper. Study on hydrogen storage ability of Mg-3Ni-2MnO2-nCNTs with different composition carbon nanotubes has been carried out. The result show that Mg-3Ni-2MnO2-nCNTs excellent heat conductivity and good hydrogen storage (more than 6%vol) ability, the CNTs improve the mass transfer and heat transfer properties of the Mg-3Ni-2MnO2, thus enhancing the kinetic property of hydrogen absorption and desorption of the hydrogen storage nanocomposites, and raising the hydrogen storage capacity. Due to the addition of the carbon nanotubes, the milling stress in the process of preparing the Mg-based namocomposites is reduced, the components can be closely bonded easily, and the additives can play better catalytic roles enhancing the kinetic property of hydrogen absorption and desorption of the hydrogen storage nanocomposites, and raising the hydrogen storage capacity. Due to the addition of the carbon nanotubes, the milling stress in the process of preparing the Mg-based namocomposites is reduced, the components can be closely bonded easily, and the additives can play better catalytic roles.

Sun, Hong-Fei; Liang, Shu-Jin; Yu, Zheng-Xing; Fang, Wen-Bin

78

Facile chemical synthesis of nanoporous layered ?-MnO2 thin film for high-performance flexible electrochemical capacitors  

NASA Astrophysics Data System (ADS)

Layered ?-MnO2 thin films with a three-dimensional nanostructure are successfully fabricated on stainless steel foil substrates for flexible electrochemical capacitors by a facile and effective chemical bath deposition technology from ethanol and potassium permanganate solution at 15 °C. The as-prepared thin films display nanoporous morphology and a water contact angle of 20°. Energy-dispersive X-ray spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy analyses reveal that the thin films are composed of ?-MnO2. Electrochemical data demonstrate that the ?-MnO2 thin film electrodes can deliver a high special capacitance of 447 F/g at 2 mV/s, and provide a good capacitance retention ratio of 87% after 1000 continuous cycles at 10 mV/s in 0.5 M Na2SO4. Compressive and tensile bending tests show that the as-prepared electrodes can steadily work over a wide range of applied curvatures between -2.5 cm-1 (tension) and 2.5 cm-1 (compression). Only a small decrease in special capacitance (0.9% at a curvature of 2.5 cm-1 under compressive strain, or 1.2% at a curvature of -2.5 cm-1 under tensile strain) is observed even after bending for 200 cycles, indicating the excellent mechanical flexibility and electrochemical stability of the ?-MnO2 thin film electrodes.

Hu, Yu; Wang, Jun; Jiang, Xionghua; Zheng, Yanfeng; Chen, Zhenxing

2013-04-01

79

Charge storage mechanism of sonochemically prepared MnO 2 as supercapacitor electrode: Effects of physisorbed water and proton conduction  

Microsoft Academic Search

The charge storage mechanism of nanostructured hydrated manganese dioxide, as a supercapacitor electrode, was investigated with respect to the role of amount of hydrates on the electrolyte cations diffusion. The MnO2 materials (?- and layered types), prepared by a novel ultrasonic aided procedure. Thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier transform infrared (FT-IR) spectroscopy were employed to

M. Ghaemi; F. Ataherian; A. Zolfaghari; S. M. Jafari

2008-01-01

80

Urchinlike MnO2 nanoparticles for the direct electrochemistry of hemoglobin with carbon ionic liquid electrode.  

PubMed

In this paper an urchinlike MnO(2) nanoparticle was synthesized by hydrothermal method and applied to the protein electrochemistry for the first time. By using a carbon ionic liquid electrode (CILE) as the basal electrode, hemoglobin (Hb) was immobilized on the surface of CILE with chitosan (CTS) and MnO(2) nanoparticle composite materials. Spectroscopic results indicated that Hb molecules retained its native structure in the composite film. A pair of well-defined redox peaks appeared on the cyclic voltammogram with the formal peak potential as -0.180 V (vs. SCE), which indicated that direct electron transfer of Hb was realized on the modified electrode. The result can be attributed to the specific characteristic of MnO(2) nanoparticle and the advantages of CILE, which facilitated the electron transfer rate. The fabricated CTS-MnO(2)-Hb/CILE showed good electrocatalytic ability to the reduction of trichloroacetic acid (TCA). Under the optimal conditions the catalytic current was in linear to TCA concentration in the range from 0.5 to 16.0 mmol L(-1) with the detection limit calculated as 0.167 mmol L(-1) (3?). The result indicated that urchinlike MnO(2) nanoparticle had the potential application in the third generation electrochemical biosensors. PMID:20926275

Zhu, Zhihong; Qu, Lining; Niu, Qingjuan; Zeng, Yan; Sun, Wei; Huang, Xintang

2010-09-16

81

?-MnO2 nanowires as building blocks for the construction of 3D macro-assemblies.  

PubMed

A 3D macro-assembly with ?-MnO(2) nanowires as flexible building blocks was obtained by a simple hydrothermal method. The sample with an interconnected open porous structure shows excellent mechanical strength, selective adsorption of cationic dyes and some certain types of toxic heavy metal ions. PMID:22552214

Long, Yong; Hui, Jun-feng; Wang, Peng-peng; Hu, Shi; Xu, Biao; Xiang, Guo-lei; Zhuang, Jing; Lü, Xing-qiang; Wang, Xun

2012-05-03

82

Graphene oxide-dispersed pristine CNTs support for MnO2 nanorods as high performance supercapacitor electrodes.  

PubMed

A MnO2 -CNT-graphene oxide (MCGO) nanocomposite is fabricated using graphene oxide (GO) as a surfactant to directly disperse pristine carbon nanotubes (CNTs) for the subsequent deposition of MnO2 nanorods. The resulting MCGO nanocomposite is used as a supercapacitor electrode that shows ideal capacitive behavior (i.e., rectangular-shaped cyclic voltammograms), large specific capacitance (4.7?times higher than that of free MnO2 ) even at high mass loading (3.0?mg?cm(-2) ), high energy density (30.4-14.2?Wh?kg(-1) ), large power density (2.6-50.5?kW?kg(-1) ), and still retains approximately 94?% of the initial specific capacitance after 1000?cycles. The advanced capacity, rate capability, and cycling stability may be attributed to the unique architecture, excellent ion wettability of GO with enriched oxygen-containing functional groups, high conductivity of CNTs, and their synergistic effects when combined with the other components. The results suggest that the MnO2 -CNT-GO hybrid nanocomposite architecture is very promising for next generation high-performance energy storage devices. PMID:23417925

You, Bo; Li, Na; Zhu, Hongying; Zhu, Xiaolan; Yang, Jun

2013-02-18

83

Hierarchically structured MnO2 nanowires supported on hollow Ni dendrites for high-performance supercapacitors  

NASA Astrophysics Data System (ADS)

We report a hierarchical Ni@MnO2 structure consisting of MnO2 nanowires supported on hollow Ni dendrites for high-performance supercapacitors. The Ni@MnO2 structure, which was prepared via a facile electrodeposition method, is highly porous and appears like a forest of pine trees grown vertically on a substrate. At a MnO2 mass loading of 0.35 mg cm-2, the Ni@MnO2 electrode demonstrated a specific capacitance of 1125 F g-1 that is close to the theoretical value. In addition, a remarkable high-rate performance (766 F g-1 at a discharge current density of 100 A g-1) was achieved. Electrochemical tests in a two-electrode configuration for the Ni@MnO2 structure with a high MnO2 loading of 3.6 mg cm-2 showed a low equivalent series resistance (ESR) of 1 ? and a high specific power of 72 kW kg-1. This superior performance can be attributed to the highly porous and hierarchical structure of Ni@MnO2 that favors rapid diffusion of an electrolyte, highly conductive pathway for electron transport, and efficient material utilization.We report a hierarchical Ni@MnO2 structure consisting of MnO2 nanowires supported on hollow Ni dendrites for high-performance supercapacitors. The Ni@MnO2 structure, which was prepared via a facile electrodeposition method, is highly porous and appears like a forest of pine trees grown vertically on a substrate. At a MnO2 mass loading of 0.35 mg cm-2, the Ni@MnO2 electrode demonstrated a specific capacitance of 1125 F g-1 that is close to the theoretical value. In addition, a remarkable high-rate performance (766 F g-1 at a discharge current density of 100 A g-1) was achieved. Electrochemical tests in a two-electrode configuration for the Ni@MnO2 structure with a high MnO2 loading of 3.6 mg cm-2 showed a low equivalent series resistance (ESR) of 1 ? and a high specific power of 72 kW kg-1. This superior performance can be attributed to the highly porous and hierarchical structure of Ni@MnO2 that favors rapid diffusion of an electrolyte, highly conductive pathway for electron transport, and efficient material utilization. Electronic supplementary information (ESI) available: More TEM and SEM images, digital photo, XPS, and XRD of the samples. See DOI: 10.1039/c3nr00209h

Sun, Zhipeng; Firdoz, Shaik; Ying-Xuan Yap, Esther; Li, Lan; Lu, Xianmao

2013-05-01

84

Improvement in selectivity of NO2 sensors based on WO3 thin films with MnO2 filters deposited by radio frequency sputtering  

Microsoft Academic Search

Thin-film WO3 sensor with a MnO2 filter was prepared to reduce interference of O3 for NO2 detection. The multi-films (WO3 film, MnO2 filter and WO3+MnO2 insulting layer) were deposited by radio frequency sputtering. The microstructure and crystalline phase of the films were characterized with SEM and XRD. The sensors were tested for 25-200 ppb O3 and 50-400 ppb NO2 in

C. Zhang; A. Boudiba; C. Navio; M.-G. Olivier; R. Snyders; M. Debliquy

2011-01-01

85

The controllable syntheses and electrochemical study of 1-dimensional nanowires, 2-dimensional nanoplatelets, and 3-dimensional nanotowers of MnO2.  

PubMed

We report a facile hydrothermal synthetic approach to selectively produce 1-dimensional, 2-dimensional, or 3-dimensional MnO2 nanomaterials reliably and conveniently. The influences of reaction conditions on the morphology and crystallographic forms and the formation mechanism of the as-obtained MnO2 nanostructures have been studied in this work. And the materials produced by this method have excellent crystalline nature. Preliminary electrochemical study indicates that the as-prepared 2-dimensional MnO2 nanomaterials are excellent cathode materials using in lithium batteries. PMID:17663269

Yan, Dong-Wei; Wang, Chun-Ru

2007-07-01

86

Electrodeposited Manganese Oxides on Three-Dimensional Carbon Nanotube Substrate: Supercapacitive Behaviour in Aqueous and Organic Electrolytes  

SciTech Connect

Thin amorphous manganese oxide layers with a thickness of 3-5nm are electrodeposited on a carbon nanotube (CNT) film substrate that has a three-dimensional nanoporous structure (denoted asMnO2/CNT electrode). For the purpose of comparison, manganese oxide films are also electrodeposited on a flat Pt-coated Si wafer substrate (denoted as MnO2 film electrode). The pseudocapacitive properties of the MnO2 film and MnO2/CNT electrodes are examined in both aqueous electrolyte (1.0M KCl) and nonaqueousorganic electrolyte (1.0M LiClO4 in propylene carbonate). While both types of electrode showpseudocapacitive behaviour in the aqueous electrolyte, only the MnO2/CNT electrode does so in the organic electrolyte, due to its high oxide/electrolyte interfacial area and improved electron conduction through the CNT substrate. Compared with the MnO2 film electrode, the MnO2/CNT electrode shows a much higher specific capacitance and better high-rate capability, regardless of the electrolyte used.Use of the organic electrolyte results in a ?6 times higher specific energy compared with that obtained with the aqueous electrolyte, while maintaining a similar specific power. The construction of a threedimensional nanoporous network structure consisting of a thin oxide layer on a CNT film substrate at the nm scale and the use of an organic electrolyte are promising approaches to improving the specific energyof supercapacitors.

Nam,K.W.; Yang,X.

2009-03-01

87

Amorphous MnO 2 –TiO 2 Composites as Sorbents for Sr 2+ and UO 2 2+  

Microsoft Academic Search

Hydrous, amorphous MnO2–TiO2 composites demonstrating high affinity towards strontium and uranium at pH = 7 are obtained by means of template synthesis. The best distribution coefficients, as found using model solutions (KdSr = 55000 mL\\/g and KdU = 40000 mL\\/g) and Chernobyl shelter water (KdSr = 3800 mL\\/g), are gained for the samples containing equimolar amounts of manganese dioxide and

Oksana I. Pendelyuk; Tetyana V. Lisnycha; Volodymyr V. Strelko; Sviatoslav A. Kirillov

2005-01-01

88

Evaluation of ?-MnO 2as a VOC Removal Catalyst: Comparison with a Noble Metal Catalyst  

Microsoft Academic Search

The performances of two very active catalysts for VOC removal (one metal oxide and one noble metal catalyst, namely ?-MnO2and Pt\\/TiO2) are compared. The comparison takes into account not only the activity but also the sensitivity to competition effects between compounds, the influence of water vapor and the stability. The metal oxide catalyst proves to be more active than the

C. Lahousse; A. Bernier; P. Grange; B. Delmon; P. Papaefthimiou; T. Ioannides; X. Verykios

1998-01-01

89

Enhanced permanganate in situ chemical oxidation through MnO 2 particle stabilization: Evaluation in 1-D transport systems  

Microsoft Academic Search

In situ chemical oxidation using permanganate is an increasingly employed approach to organic contaminant remediation at hazardous waste sites. Manganese dioxide (MnO2) particles form as a by-product of the reaction of permanganate with contaminants and naturally-reduced subsurface materials. These particles are of interest because they have the potential to deposit in the subsurface and impact the flow regime in\\/around permanganate

Michelle Crimi; Mark Quickel; Saebom Ko

2009-01-01

90

Multifunctional Free-Standing Membrane from the Self-assembly of Ultralong MnO2 Nanowires.  

PubMed

In this work, we report the preparation of a free-standing membrane with strong mechanical stability and flexibility through a facile vacuum filtration approach. A field-emission scanning electron microscopy image demonstrates that the membrane composed of MnO2 nanowires is 50 nm in width and up to 100 ?m long and the nanowires are assembled in parallel into bundles. A possible formation mechanism for the ultralong nanowires and the free-standing membrane has been proposed. Meanwhile, the properties of the membrane could be controlled by incorporating different materials to achieve composite membranes. In order to demonstrate the broad applicability of the MnO2 membrane, we fabricate a variety of composite membranes exhibiting various novel properties including magnetism and reversibly switchable wettability between hydrophilicity and hydrophobicity through various material modification, including CoFe2O4 nanoparticles and organic triethoxy(octyl)silane. Furthermore, the free-standing membrane could also simultaneously be functionalized with two materials, which reveal multiple properties. The synthesis method of a free-standing MnO2 membrane is simple and environmentally friendly, and it is easily scalable for industry. These composite membranes constitute a significant contribution to advanced technology. PMID:23815464

Lan, Bang; Yu, Lin; Lin, Ting; Cheng, Gao; Sun, Ming; Ye, Fei; Sun, Qingfeng; He, Jun

2013-07-16

91

Hierarchically structured MnO2 nanowires supported on hollow Ni dendrites for high-performance supercapacitors.  

PubMed

We report a hierarchical Ni@MnO2 structure consisting of MnO2 nanowires supported on hollow Ni dendrites for high-performance supercapacitors. The Ni@MnO2 structure, which was prepared via a facile electrodeposition method, is highly porous and appears like a forest of pine trees grown vertically on a substrate. At a MnO2 mass loading of 0.35 mg cm(-2), the Ni@MnO2 electrode demonstrated a specific capacitance of 1125 F g(-1) that is close to the theoretical value. In addition, a remarkable high-rate performance (766 F g(-1) at a discharge current density of 100 A g(-1)) was achieved. Electrochemical tests in a two-electrode configuration for the Ni@MnO2 structure with a high MnO2 loading of 3.6 mg cm(-2) showed a low equivalent series resistance (ESR) of 1 ? and a high specific power of 72 kW kg(-1). This superior performance can be attributed to the highly porous and hierarchical structure of Ni@MnO2 that favors rapid diffusion of an electrolyte, highly conductive pathway for electron transport, and efficient material utilization. PMID:23571645

Sun, Zhipeng; Firdoz, Shaik; Ying-Xuan Yap, Esther; Li, Lan; Lu, Xianmao

2013-05-21

92

Processing-structure-property-performance investigations of lithium manganese-based oxides for lithium rechargeable batteries  

Microsoft Academic Search

A study of the processing - structure - property - performance interrelationship was performed on several lithium manganese oxides that are candidates for use in lithium rechargeable batteries. The materials studied were LiMn 2O4, Mn-substituted LiMn2O4 (LiMn 2-yMeyO4), and Li1.5Na0.5 MnO2.85I0.12. Processing evaluations pertained to the substitution of Mn by other cations (Me = Li, Co, or Ni). Atomic and

Craig Richard Horne

2000-01-01

93

Development of a method for total plasma thiols measurement using a disposable screen-printed carbon electrode coupled with a MnO 2 reactor  

Microsoft Academic Search

We report here an electrochemical approach for total plasma thiols measurement using a disposable screen-printed carbon electrode coupled with a MnO2 reactor. In this approach, catechol is used as an electrochemical indicator to monitor the nucleophilic addition of thiols to the o-quinone. A reactor containing MnO2 particles is effectively combined into the flow injection analysis (FIA) system not only to

Chun-Yen Liao; Jyh-Myng Zen

2008-01-01

94

Influence of SiO2 on the structure-controlled synthesis and magnetic properties of prismatic MnO2 nanorods  

NASA Astrophysics Data System (ADS)

Silicon dioxide-doped tetragonal MnO2 single crystalline prismatic nanorods have been successfully synthesized through a facile hydrothermal route at a temperature of 250?° C with a reaction time as quick as 5 h. The synthesized MnO2 prismatic nanorods were characterized by x-ray diffraction, field emission scanning electron microscopy, energy dispersive x-ray analysis, transmission electron microscopy, high resolution transmission electron microscopy with selected area electron diffraction and Raman spectroscopy. Experimental results show that single crystalline tetragonal MnO2 nanorods have been successfully synthesized at all doping concentrations and that nanorods with a prismatic surface morphology have been obtained at 20 mass% of SiO2. The diameter of as-prepared MnO2 nanorods increases from 125 to 250 nm on increasing the dopant concentration. X-ray photoelectron spectroscopy analysis confirms the presence of valence Si (2p) of SiO2 in the as-prepared MnO2 nanostructures. The intensity of Raman modes clearly increases with increasing doping concentration, indicating an improvement in the structural aspects of the MnO2 nanorods. The magnetic properties of the products have been evaluated using a vibrating sample magnetometer, revealing that the as-prepared MnO2 nanorods exhibit weak ferromagnetic behavior at room temperature. The Néel temperature of the as-obtained products is calculated as 97 K. On the basis of the structural information, a growth mechanism is proposed for the formation of prismatic-like 1D MnO2 nanorods.

Toufiq, Arbab Mohammad; Wang, Fengping; Javed, Qurat-ul-ain; Li, Yan

2013-10-01

95

Influence of SiO2 on the structure-controlled synthesis and magnetic properties of prismatic MnO2 nanorods.  

PubMed

Silicon dioxide-doped tetragonal MnO2 single crystalline prismatic nanorods have been successfully synthesized through a facile hydrothermal route at a temperature of 250?° C with a reaction time as quick as 5 h. The synthesized MnO2 prismatic nanorods were characterized by x-ray diffraction, field emission scanning electron microscopy, energy dispersive x-ray analysis, transmission electron microscopy, high resolution transmission electron microscopy with selected area electron diffraction and Raman spectroscopy. Experimental results show that single crystalline tetragonal MnO2 nanorods have been successfully synthesized at all doping concentrations and that nanorods with a prismatic surface morphology have been obtained at 20 mass% of SiO2. The diameter of as-prepared MnO2 nanorods increases from 125 to 250 nm on increasing the dopant concentration. X-ray photoelectron spectroscopy analysis confirms the presence of valence Si (2p) of SiO2 in the as-prepared MnO2 nanostructures. The intensity of Raman modes clearly increases with increasing doping concentration, indicating an improvement in the structural aspects of the MnO2 nanorods. The magnetic properties of the products have been evaluated using a vibrating sample magnetometer, revealing that the as-prepared MnO2 nanorods exhibit weak ferromagnetic behavior at room temperature. The Néel temperature of the as-obtained products is calculated as 97 K. On the basis of the structural information, a growth mechanism is proposed for the formation of prismatic-like 1D MnO2 nanorods. PMID:24045288

Toufiq, Arbab Mohammad; Wang, Fengping; Javed, Qurat-Ul-Ain; Li, Yan

2013-09-17

96

Highly flexible pseudocapacitor based on freestanding heterogeneous MnO2/conductive polymer nanowire arrays.  

PubMed

Flexible electronics such as wearable electronic clothing, paper-like electronic devices, and flexible biomedical diagnostic devices are expected to be commercialized in the near future. Flexible energy storage will be needed to power these devices. Supercapacitor devices based on freestanding nanowire arrays are promising high power sources for these flexible electronics. Electrodes for these supercapacitor devices consisting of heterogeneous coaxial nanowires of poly (3,4-ethylenedioxythiophene) (PEDOT)-shell and MnO(2)-core materials have been shown in a half cell system to have improved capacitance and rate capabilities when compared to their pure nanomaterials; however, their performance in a full cell system has not been fully investigated. Herein, these coaxial nanowires are tested in both a symmetric and an asymmetric (utilizing a PEDOT nanowire anode) full cell configuration in the aspect of charge storage, charge rate, and flexibility without using any carbon additives and polymer binders. It is found that the asymmetric cell outperforms the symmetric cell in terms of energy density, rate capability, and cycle ability. The asymmetric device's electrode materials display an energy density of 9.8 Wh/kg even at a high power density of 850 W kg(-1). This device is highly flexible and shows fast charging and discharging while still maintaining 86% of its energy density even under a highly flexed state. The total device is shown to have a total capacitance of 0.26 F at a maximum voltage of 1.7 V, which is capable of providing enough energy to power small portable devices. PMID:22298230

Duay, Jonathon; Gillette, Eleanor; Liu, Ran; Lee, Sang Bok

2012-02-01

97

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

98

Microstructure and ferroelectric properties of MnO2-doped bismuth-layer (Ca,Sr)Bi4Ti4O15 ceramics  

NASA Astrophysics Data System (ADS)

We have studied the microstructures and ferroelectric properties of MnO2-doped bismuth-layered (Ca,Sr)Bi4Ti4O15 (CSBTM). The piezoelectric coefficient, dielectric loss, mechanical quality factor, and the P-E hysteresis loop measurements indicate that Mn ions entered both the A and B sites of the pseudoperovskite-layered structure, creating ``soft'' and ``hard'' doping effects simultaneously. Scanning electron microscopy and energy dispersion spectroscopy showed that the platelike grains in CSBTM ceramics become larger with the increase of MnO2 additive, and Mn ions are found inside the grains as well as in the grain boundaries. The lattice parameter, room-temperature dielectric constant, and the Curie temperature do not vary with MnO2 additive. We conclude that the Mn3+ ions play a critical role in the effects of soft and hard behaviors since it can enter both the A and B sites of the perovskite structure.

Li, Gurong; Zheng, Liaoying; Yin, Qingrui; Jiang, Bei; Cao, Wenwu

2005-09-01

99

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

100

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

101

Porous MnO2 for use in a high performance supercapacitor: replication of a 3D graphene network as a reactive template.  

PubMed

Graphene oxide hydrogel is used as a reactive template to prepare nanoporous materials with a 3D microstructure. The as-prepared porous MnO2 shows a capacitance retention of ?70.6% at a current density as high as 15 A g(-1), resulting from the 3D interconnected ion transport channel replicated from the graphene oxide hydrogel. PMID:24141912

Xie, Xiaoying; Zhang, Chen; Wu, Ming-Bo; Tao, Ying; Lv, Wei; Yang, Quan-Hong

2013-10-31

102

Oxidation of As(III) by MnO 2 in the absence and presence of Fe(II) under acidic conditions  

NASA Astrophysics Data System (ADS)

Oxidation of As(III) by natural manganese (hydr)oxides is an important geochemical reaction mediating the transformation of highly concentrated As(III) in the acidic environment such as acid mine drainage (AMD) and industrial As-contaminated wastewater, however, little is known regarding the presence of dissolved Fe(II) on the oxidation process. In this study, oxidation of As(III) in the absence and presence of Fe(II) by MnO 2 under acidic conditions was investigated. Kinetic results showed that the presence of Fe(II) significantly inhibited the removal of As(III) (including oxidation and sorption) by MnO 2 in As(III)-Fe(II) simultaneous oxidation system even at the molar ratio of Fe(II):As(III) = 1/64:1, and the inhibitory effects increased with the increasing ratios of Fe(II):As(III). Such an inhibition could be attributed to the formation of Fe(III) compounds covering the surface of MnO 2 and thus preventing the oxidizing sites available to As(III). On the other hand, the produced Fe(III) compounds adsorbed more As(III) and the oxidized As(V) on the MnO 2 surface with an increasing ratio of Fe(II):As(III) as demonstrated in kinetic and XPS results. TEM and EDX results confirmed the formation of Fe compounds around MnO 2 particles or separated in solution in Fe(II) individual oxidation system, Fe(II) pre-treated and simultaneous oxidation processes, and schwertmannite was detected in Fe(II) individual and Fe pre-treated oxidation processes, while a new kind of mineral, probably amorphous FeOHAs or FeAsO 4 particles were detected in Fe(II)-As(III) simultaneous oxidation process. This suggests that the mechanisms are different in Fe pre-treated and simultaneous oxidation processes. In the Fe pre-treated and MnO 2-mediated oxidation pathway, As(III) diffused through a schwertmannite coating formed around MnO 2 particles to be oxidized. The newly formed As(V) was adsorbed onto the schwertmannite coating until its sorption capacity was exceeded. Arsenic(V) then diffused out of the coating and was released into the bulk solution. The diffusion into the schwertmannite coating and the oxidation of As(III) and sorption of both As(V) and As(III) onto the coating contributed to the removal of total As from the solution phase. In the simultaneous oxidation pathway, the competitive oxidation of Fe(II) and As(III) on MnO 2 occurred first, followed by the formation of FeOHAs or FeAsO 4 around MnO 2 particles, and these poorly crystalline particles of FeOHAs and FeAsO 4 remained suspended in the bulk solution to adsorb As(III) and As(V). The present study reveals that the formation of Fe(III) compounds on mineral surfaces play an important role in the sorption and oxidation of As(III) by MnO 2 under acidic conditions in natural environments, and the mechanisms involved in the oxidation of As(III) depend upon how Fe(II) is introduced into the As(III)-MnO 2 system.

Han, Xu; Li, Yi-Liang; Gu, Ji-Dong

2011-01-01

103

Improvement in the etching performance of the acrylonitrile-butadiene-styrene resin by MnO2-H3PO4-H2SO4 colloid.  

PubMed

The present study aimed to evaluate the surface etching of the acrylonitrile-butadiene-styrene (ABS) resin in the MnO2-H3PO4-H2SO4 colloid. To enhance the soluble Mn(IV) ion concentration and improve the etching performance of ABS resin, H3PO4 was added as a complexing agent into the MnO2-H2SO4 etching system. The effects of the H2SO4 concentration and etching time on the surface topography, surface roughness, adhesion strength, and the surface chemistry of the ABS substrates were investigated. The optimal oxidation potentials of MnO2 in the colloids decreased from 1.426 to 1.369 V with the addition of H3PO4. Though the etching conditions changed from 70 °C for 20 min to 60 °C for 10 min, the adhesion strength between the ABS substrates and electroless copper film increased from 1.19 to 1.33 KN/m after etching treatment. This could be attributed to the significant increase of the soluble Mn(IV) ion concentration in the MnO2-H3PO4-H2SO4 colloid. The surface chemistry results demonstrated that the oxidation reaction of -C?C- bonds in the polybutadiene phase was accelerated in the etching process by the addition of H3PO4, and the abundant -COOH and -OH groups were formed rapidly on the ABS surface with the etching treatment. These results were in agreement with the results of surface scanning electron microscopic observations and adhesion strength measurement. The results suggested that the MnO2-H3PO4-H2SO4 colloid was an effective surface etching system for the ABS surface roughness. PMID:23611532

Zhao, Wenxia; Ding, Jie; Wang, Zenglin

2013-05-09

104

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

105

A consistent model for surface complexation on birnessite (-MnO 2) and its application to a column experiment  

NASA Astrophysics Data System (ADS)

Available surface complexation models for birnessite required the inclusion of bidentate bonds or the adsorption of cation-hydroxy complexes to account for experimentally observed H +/M m+ exchange. These models contain inconsistencies and therefore the surface complexation on birnessite was re-examined. Structural data on birnessite indicate that sorption sites are located on three oxygens around a vacancy in the octahedral layer. The three oxygens together carry a charge of -2, i.e., constitute a doubly charged sorption site. Therefore a new surface complexation model was formulated using a doubly charged, diprotic, sorption site where divalent cations adsorbing via inner-sphere complexes bind to the three oxygens. Using the diprotic site concept we have remodeled the experimental data for sorption on birnessite by Murray (1975) using the surface complexation model of Dzombak and Morel (1990). Intrinsic constants for the surface complexation model were obtained with the non-linear optimization program PEST in combination with a modified version of PHREEQC (Parkhurst, 1995). The optimized model was subsequently tested against independent data sets for synthetic birnessite by Balistrieri and Murray (1982) and Wang et al. (1996). It was found to describe the experimental data well. Finally the model was tested against the results of column experiments where cations adsorbed on natural MnO 2 coated sand. In this case as well, the diprotic surface complexation model gave an excellent description of the experimental results.

Appelo, C. A. J.; Postma, D.

1999-10-01

106

Microfluidic etching for fabrication of flexible and all-solid-state micro supercapacitor based on MnO2 nanoparticles.  

PubMed

Micro-supercapacitors are a promising candidate whose reliability and performances are struggling to meet the energy demands dictated by the incoming generation of miniaturized electronic devices. In this paper, we describe a facile and low-cost method for fabricating flexible and all-solid-state micro supercapacitors by microfluidic etching. The micro-supercapacitor configuration is composed of sub-10-nm-scale MnO(2) nanoparticle interdigital microelectrode fingers prepared by microfluidic etching with H(3)PO(4)-PVA thin films as both the solid-state electrolyte and the flexible substrate. The entire device shows outstanding electrochemical performances with high specific capacitance and stable cycle life, and the performance can be mostly preserved even conditions of under repeated bending. The technique we describe here is a universal method for fabricating a micro-supercapacitor, since the microfluidic etching can be extended to most active materials which can be used for energy- and power-devices, and there are many other choices for the solid electrolyte. Thus, these micro-supercapacitors provide a promising power source in microelectromechanical systems (MEMS), wearable electronics and other general requirements. PMID:21369565

Xue, Mianqi; Xie, Zhuang; Zhang, Lesheng; Ma, Xinlei; Wu, Xinglong; Guo, Yuguo; Song, Weiguo; Li, Zhibo; Cao, Tingbing

2011-03-02

107

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

108

Fabrication and characterization of a novel inorganic MnO 2\\/LDHs multilayer thin film via a layer-by-layer self-assembly method  

Microsoft Academic Search

Multilayer thin films comprising negatively charged MnO2 sheets and positively charged Mg–Al LDHs sheets have been prepared by the electrostatic layer-by-layer adsorption technique. The resulting films were characterized by UV–vis spectra, scanning electron microscope (SEM), X-ray photoelectron spectra (XPS), and so on. UV–vis spectra show that the absorbance values at characteristic wavelengths of the multilayer films increase almost linearly with

Xiong Zhang; Yi Wang; Xu Chen; Wensheng Yang

2008-01-01

109

Piezoelectric Properties of Low Loss and Low Temperature sintering PMN-PNN-PZT Ceramics According to the Amount of MnO2 Addition  

Microsoft Academic Search

In this study, in order to develop the composition ceramics for low loss and low temperature sintering multilayer piezoelectric actuator, PMN-PNN-PZT ceramics were fabricated using Li2CO3 and Na2CO3 as sintering aids, and their piezoelectric and dielectric characteristics were investigated according to the amount of MnO2 addition. At the sintering temperature of 900 , density and mechanical quality factor (Qm) of

Juhyun Yoo; Sangho Lee; Lakhoon Hwang; Yeongho Jeong

2006-01-01

110

Effect of MnO2 Addition on Sintering Properties of 18NiO-NiFe2O4 Composite Ceramics: Preliminary Results  

NASA Astrophysics Data System (ADS)

NiFe2O4 samples with small amounts of MnO2 were prepared via ball-milling process and two-step sintering process from commercial powders. Sintered density, average grain size, and microstructure of Mn-doped 18NiO-NiFe2O4 composite ceramics have been investigated by means of x-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy. Bending strength was measured by three-point method. The results show that the crystalline structures of the ceramic matrix are still NiFe2O4 spinel structure and Mn ions homogeneously distribute in both the grains interiors and the grain boundaries. When 1 wt.% MnO2 was added, the values of relative density and bending strength of composite ceramics reached their respective maximum of 93.6% and 38.75 MPa, respectively. It is preliminarily found that MnO2 can reduce the sintering temperature obviously because of partial substitution of Fe3+ with Mn4+ in NiFe2O4 lattice.

Du, Jinjing; Liu, Yihan; Yao, Guangchun; Zhang, Zhigang

2012-09-01

111

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

112

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

113

Uptake, distribution and behavioral effects of inhalation exposure to manganese (MnO2) in the adult mouse.  

PubMed

Adult male mice were exposed either to sublethal levels of MnO2 dust or filtered air (control group) 7 hours/day, 5 days/week for 16 to 32 weeks. Following a 16 week initial exposure period, randomly selected samples (8 animals) from both the control and Mn-exposed groups were observed for behavioral performance (ambulations and rearings in the open-field, "hole-in-board" explorations, rotarod) and learning (passive avoidance) and tissue Mn levels were determined via atomic absorption spectrometry. Exposure continued for the remaining animals and the sampling procedure was repeated biweekly for an additional 8 time points. At week 32, Mn exposure was terminated. However, biweekly testing of the remaining animals continued for an additional 3 time points. Mn-exposed animals had significantly higher blood, liver, kidney, lung, cerebrum, cerebellum plus brainstem, and testis Mn levels than control animals. With the exception of the liver, these levels declined with increasing exposure time. No histopathologic effects attributable to Mn-exposure were observed. However, significant overall effects on growth and behavior were obtained. Specifically, Mn-exposed subjects weighed more, executed more rearings in the open-field, and tended to exhibit longer latencies to enter the open-field. When the post-exposure data were analyzed separately, no significant effects were obtained. While no general relationship was obtained between tissue Mn levels and behavior, selected behavioral measures did correlate with tissue Mn levels. Animals exposed via feeding to comparable Mn levels across the same length of exposure employed in the inhalation study did not demonstrate any significant behavioral alterations. PMID:3873032

Morganti, J B; Lown, B A; Stineman, C H; D'Agostino, R B; Massaro, E J

1985-01-01

114

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

115

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

116

A hierarchical nanostructure consisting of amorphous MnO 2, Mn 3O 4 nanocrystallites, and single-crystalline MnOOH nanowires for supercapacitors  

Microsoft Academic Search

In this communication, a porous hierarchical nanostructure consisting of amorphous MnO2 (a-MnO2), Mn3O4 nanocrystals, and single-crystalline MnOOH nanowires is designed for the supercapacitor application, which is prepared by a simple two-step electrochemical deposition process. Because of the gradual co-transformation of Mn3O4 nanocrystals and a-MnO2 nanorods into an amorphous manganese oxide, the cycle stability of a-MnO2 is obviously enhanced by adding

Chi-Chang Hu; Ching-Yun Hung; Kuo-Hsin Chang; Yi-Lin Yang

2011-01-01

117

Thermal and photodegradation of MnO 2-, NaBO 3- and organic hydroperoxide-cured polysulfides: products and pathways  

Microsoft Academic Search

The thermal and photodegradation of a number of linear polysulfides (LP) H(SC2H4OCH2OC2H4S)nH, cured using inorganic (MnO2, NaBO3) and organic (t-butyl hydroperoxide or TBHP) curatives, have been studied by 1H and 13C NMR spectroscopy, IR spectroscopy and electrospray ionisation mass spectrometry (ESI). We have found that cured-LPs degrade thermally and photochemically by two main parallel pathways namely (i) a free radical

Andrea Mahon; Terence J. Kemp; Robert J. Coates

1998-01-01

118

H-TiO(2) @MnO(2) //H-TiO(2) @C core-shell nanowires for high performance and flexible asymmetric supercapacitors.  

PubMed

A flexible solid-state asymmetric supercapacitor device with H-TiO(2) @MnO(2) core-shell NWs as the positive electrode and H-TiO(2) @C core-shell NWs as the negative electrode is developed. This device operates in a 1.8 V voltage window and is able to deliver a high specific capacitance of 139.6 F g(-1) and maximum volumetric energy density of 0.30 mWh cm(-3) with excellent cycling performance and good flexibility. PMID:23080535

Lu, Xihong; Yu, Minghao; Wang, Gongming; Zhai, Teng; Xie, Shilei; Ling, Yichuan; Tong, Yexiang; Li, Yat

2012-10-19

119

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

120

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

121

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

122

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

123

Microstructure and varistor properties of ZnO-V2O5-MnO2 ceramics with Ta2O5 addition  

NASA Astrophysics Data System (ADS)

The effect of Ta2O5 addition on microstructure, electrical properties, and dielectric characteristics of the quaternary ZnO-V2O5-MnO2 vaistor ceramics was investigated. Analysis of the microstructure indicated that the quaternary ZnO-V2O5-MnO2-Ta2O5 ceramics consisted of mainly ZnO grain and minor secondary phases such as Zn3(VO4)2, ZnV2O4, TaVO5, and Ta2O5. As the amount of Ta2O5 increased, the sintered density increased from 94.8 to 97.2% of the theoretical density (5.78 g/cm3 for ZnO), whereas the average grain size decreased from 7.7 to 6.0 ?m. The ceramics added with 0.05 mol% Ta2O5 exhibited the highest breakdown field (2715 V/cm) and the highest nonlinear coefficient (20). However, further increase caused ? to abruptly decrease. The Ta2O5 acted as a donor due to the increase of electron concentration in accordance with the amount of Ta2O5. The donor concentration increased from 1.97×1018 to 3.04×1018cm-3 with increasing the amount of Ta2O5 and the barrier height exhibited the maximum value (0.95 eV) at 0.05 mol% Ta2O5.

Nahm, Choon-W.

2012-07-01

124

Frustrated exchange interactions formation at low temperatures and high hydrostatic pressures in La0.70Sr0.30MnO2.85  

NASA Astrophysics Data System (ADS)

The magnetic and thermal properties of the anion-deficient La0.70Sr0.30MnO2.85 manganite are investigated in wide temperature (4-350 K) range, including under hydrostatic pressure (0-1.1 GPa). Throughout the pressure range investigated, the sample is spin glass with diffused phase transition into paramagnetic state. It is established, that spin glass state is a consequence of exchange interaction frustration of the ferromagnetic clusters embeded into antiferromagnetic clusters. The magnetic moment freezing temperature T f of ferromagnetic clusters increases under pressure, freezing temperature dependence on pressure is characterized by derivative value ˜4.5 K/GPa, while the magnetic ordering T MO temperature dependence is characterized by derivative value ˜13 K/GPa. The volume fraction of sample having ferromagnetic state is V fer ˜ 13% and it increases under a pressure of 1.1 GPa by ? V fer ? 6%. Intensification of ferromagnetic properties of the anion-deficient La0.70Sr0.30MnO2.85 manganite under hydrostatic pressure is a consequence of oxygen vacancies redistribution and unit cell parameters decrease. The most likely mechanism of frustrated exchange interactions formation is discussed.

Trukhanov, S. V.; Trukhanov, A. V.; Vasiliev, A. N.; Szymczak, H.

2010-08-01

125

Removal of manganese ions from synthetic groundwater by oxidation using KMnO(4) and the characterization of produced MnO(2) particles.  

PubMed

The aim of this study is to investigate the conditions for the removal of manganese ions from synthetic groundwater by oxidation using KMnO(4) to keep the concentration below the allowed level (0.05?mg/L). The process includes low-level aeration and addition of KMnO(4) in a Jar test system with Mn(2?+?) concentration of 0.50?mg/L, similar to that of natural groundwater in Taiwan. Different parameters such us aeration-pH, oxidant dose, and stirring speed were studied. Aeration alone was not sufficient to remove Mn(2?+?) ions completely even when the pH was increased. When a stoichiometric amount of KMnO(4) (0.96?mg/L) was used, a complete Mn(2?+?) removal was achieved within 15?min at an optimum pH of 8.0. As the amount of KMnO(4) was doubled, lower removal efficiency was obtained because the oxidant also generated manganese ions. The removal of Mn(2?+?) ions could be completed at pH 9.0 using an oxidant dose of 0.48?mg/L because Mn(2?+?) could be sorbed onto the MnO(2) particles. Finally, The MnO(2) particles were characterized using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). PMID:20962386

Phatai, P; Wittayakun, J; Grisdanurak, N; Chen, W H; Wan, M W; Kan, C C

2010-01-01

126

The Effect of Porosity on Heat Transfer and Mass Transfer of Mg-3Ni-2MnO2 Hydrogen Storage Materials Reaction Bed  

NASA Astrophysics Data System (ADS)

Hydrided Mg-3Ni-2MnO2 composite powders were prepared by mechanical milling under hydrogen atmosphere. Heat and mass transfer, the effective thermal conductivity (ETC) of the hydrided Mg-3Ni-2MnO2 powder reaction bed with various porosities were measured using a self-made apparatus. The effect of porosity on the bed is also analysized. The results show that the ETC of reaction bed is poor and it increases with decreasing porosity. Three porosities, 0.37, 0.53, 0.63 were selected in the present work. The bed with 0.53 porosity exhibits relatively fast reaction rates in both hydrogenation and dehydrogenation process. The hydrogenation process is a fast exothermic reaction resulting in a quick increase if the temperature of the bed during this process, and there is a temperature gradient: the temperature close to the bed wall is lower but higher at the center of bed. In dehydrogenation of the bed, the temperature of hydrided bed decreases due to the endothermic reaction, and the temperature at the center falls the lowest and keep at that temperature for a long time. The analyses reveal that increase of ETC don't always helps to improve the bed's hydriding and dehydriding rates. There should be an optimal porosity which helps to transfer both the heat and the mass.

Zhang, Wencong; Wang, Gang; Ma, Junfei; Wang, Zhaoyou; Wang, Erde

127

Sonolytical preparation of various types of metal nanoparticles in aqueous solution  

Microsoft Academic Search

Composite nanoparticles of Au, Pd and Pt, and nanoparticles of transition metal oxides, MnO2, were prepared by the sonochemical reduction of corresponding ions (Au(III), Pd(II), Pt(II), Pt(IV) and Mn(VII)) in an aqueous system in the presence of surfactants. The prepared noble metal particles were stable and the sizes were of the order of nanometer with narrow distribution. Surfactants were found

Taku Fujimoto; Yoshiteru Mizukoshi; Yoshio Nagata; Yasuaki Maeda; Ryuichiro Oshima

2001-01-01

128

Preparation and electrochemical characteristics of a new Li-Mn-V-O system formed from heat-treatment of a MnO 2 , NH 4 VO 3 and LiNO 3 mixture  

Microsoft Academic Search

New quarternary oxides (Li2O)x · MnO2 · yV2O5 (x = 0.125 ~ 0.25, y = 0.125 ~ 0.25), formed by heating mixtures of MnO2, NH4VO3 and LiNO3 at various Li\\/Mn and V\\/Mn atomic ratios and at different temperatures (300 ~ 400 °C in air, have been characterized by X-ray diffraction, X-ray photoelectron spectroscopy (ESCA) and infrared spectroscopy. The quarternary oxide

N. Kumagai; T. Tamachi; T. Bingda; K. Tanno

1994-01-01

129

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

130

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

131

A new type rechargeable lithium battery based on a Cu-cathode  

Microsoft Academic Search

In present work, we report a new type rechargeable lithium battery, in which a Cu-cathode in aqueous electrolyte and a Li-anode in non-aqueous electrolyte are united together by a lithium super-ionic conductor glass film (LISICON) through which only lithium-ions can pass. During the charge–discharge process, combining with the dissolution–deposition of metallic Cu (or Li) electrode, lithium ions transfer between aqueous

Yonggang Wang; Haoshen Zhou

2009-01-01

132

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

133

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

134

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

135

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

136

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

137

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

138

Importance of anisotropic Coulomb interactions and exchange to the band gap and antiferromagnetism of ?-MnO2 from DFT+U  

NASA Astrophysics Data System (ADS)

First-principles density functional theory (DFT) is used to investigate the electronic structure of ?-MnO2. From collinear spin-polarized calculations we find that DFT+Ueff predicts a gapless ferromagnet in contrast with experiment, which indicates an insulating antiferromagnet. The inclusion of anisotropic Coulomb and exchange interactions in the DFT+U approach, defining U and J explicitly, corrects these errors and leads to an antiferromagnetic ground state with a fundamental gap of 0.8 eV consistent with low-temperature experiments. To our knowledge, this work on ?-MnO2 represents the first demonstration of a case in which the application of fully anisotropic interactions in DFT+U determines the magnetic order and consequent band gap, while the more commonly used “effective-U” approach fails. Such effects are argued to be of importance in many insulating materials. The mechanism leading to an increase in band gap due to anisotropic interactions is highlighted by analytical calculation of DFT+U d-orbital eigenvalues obtained within a Kanamori-type model. Magnetic coupling constants obtained by the fitting of a Heisenberg spin Hamiltonian to the energies of a range of magnetic states assist in rationalizing the finding that anisotropic interactions enhance the stability of the experimentally observed helical antiferromagnetic order. The plane-wave projector-augmented wave (PAW) method yields poorer results for the exchange couplings than full-potential linearized augmented plane-wave (LAPW) calculations. Finally, we compare the DFT+U results with exchange couplings obtained from hybrid functionals. It is argued that anisotropic interactions should be included in DFT+U if the results are to be properly compared with those from hybrid functionals.

Tompsett, D. A.; Middlemiss, D. S.; Islam, M. S.

2012-11-01

139

Asymmetric synthesis of 2-alkyl-3-thiazoline carboxylates: stereochemistry of the MnO 2-mediated oxidation of cis- and trans-2-alkyl-thiazolidine-(4 R)-carboxylates  

Microsoft Academic Search

The asymmetric synthesis of a series of 3-thiazoline carboxylates, 2, was effected by MnO2 oxidation of the corresponding cis\\/trans thiazolidines, 1. The stereochemistry of the oxidation reaction was studied using NMR and chiral GC analyses. Compounds 2 were obtained with enantiomeric excesses (e.e.s) in the range of 40–100%.

Xavier Fernandez; Elisabet Duñach

2001-01-01

140

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

141

Processing-structure-property-performance investigations of lithium manganese-based oxides for lithium rechargeable batteries  

NASA Astrophysics Data System (ADS)

A study of the processing - structure - property - performance interrelationship was performed on several lithium manganese oxides that are candidates for use in lithium rechargeable batteries. The materials studied were LiMn 2O4, Mn-substituted LiMn2O4 (LiMn 2-yMeyO4), and Li1.5Na0.5 MnO2.85I0.12. Processing evaluations pertained to the substitution of Mn by other cations (Me = Li, Co, or Ni). Atomic and electronic structure was investigated using X-ray diffraction, FTIR, 7Li NMR, and a variety of X-ray spectroscopy techniques. The properties investigated included the voltage profile during charge and discharge in a Li metal cell along with the structural changes taking place upon lithium extraction or insertion. Performance evaluation consisted of cycling several of these materials within a Li metal cell. Among the significant findings of this study are that a dynamic Jahn-Teller distortion takes place in LiMn2O4 and that the Li + inserted derivative (Li2Mn2O4) possess a significantly greater degree of covalency with respect Mn oxides with similar atomic structure. These results are used to construct a structural reaction mechanism for the Li+ extraction and insertion reactions in LiMn2O4 and the phase transformation that accompanies Li+ insertion. In contrast, evidence for increased covalency upon lithium insertion was not apparent in Li1.5Na0.5MnO 2.85I0.12, an amorphous material. Furthermore, it was found that the distortion of the [MnO6] octahedra occurring upon Li + insertion is reversible. This is consistent with the high degree of cycling stability in this material and attributable to the amorphous nature. It was also found that the degree of covalency increases when substituting Mn with either Li, Co, or Ni. The amount of increased covalency depends on the degree of substitution and the substituent used. It was found that substitution lowers the discharge voltage along with affecting the degree of distortion and volume change that takes place during the cubic to tetragonal phase transformation concomitant with Li+ insertion. Assimilating these results with the increased cyclability of Mn substituted spinels reveals that lowering the discharge voltage and/or the volume change associated with the phase transformation will result in a spinel with improved performance. The understanding gained in this dissertation leads to guidelines for engineering improved lithium rechargeable battery electrode materials.

Horne, Craig Richard

142

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

143

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

144

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

145

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

146

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

147

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

148

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

149

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

150

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

151

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

152

Phase segregation in the hole-doped manganite Nd0.93MnO2.96: magnetic measurements and neutron diffraction  

NASA Astrophysics Data System (ADS)

Lacunar-controlled Nd0.93MnO2.96 orthorhombic perovskite prepared at 1200°C has been studied at low temperature. Magnetization measurements suggest the coexistence below 80K of ferro- and antiferromagnetic interactions between Mn atoms as in the stoichiometric parent compound NdMnO3. Nevertheless, spontaneous magnetization curves obtained after sample cooling under a magnetic field of 500Oe (FC) and without magnetic field (ZFC) reveal a much original behavior. Magnetization changes sign twice on ZFC curve; strong negative magnetization is observed below 19K on FC curve. On the basis of neutron diffraction data, this behavior is interpreted by considering the coexistence of two perovskite phases having chemical compositions and magnetic ordering temperatures slightly different; ferromagnetic components in the clusters of both phases are antiferromagnetically coupled in the range 20-80K. Ferromagnetic ordering at 19K of Nd atoms is accompanied by a rearrangement of the Mn ferromagnetic components which become parallel in all the clusters.

Ihzaz, N.; Vincent, H.; Dezanneau, G.; Roussel, H.; Dhahri, J.; Oumezzine, M.

2004-10-01

153

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

154

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

155

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

156

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

157

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

158

Study on immunosensor based on gold nanoparticles/chitosan and MnO2 nanoparticles composite membrane/Prussian blue modified gold electrode.  

PubMed

A novel and convenient immunosensor, based on the electrostatic adsorption characteristics between the positively charged MnO(2) nanoparticles (nano-MnO(2)) and chitosan (CS) composite membrane (nano-MnO(2) + CS) and the negatively charged prussian blue (PB), was prepared for the detection of carcinoembryonic antigen (CEA). Firstly, PB was electro-deposited on the surface of the gold electrode in the constant potential, and then nano-MnO(2) + CS was adsorbed onto PB-modified electrode surface. Subsequently, Gold nanoparticles (nano-Au) were electro-deposited on the nano-MnO(2) + CS-modified electrode to immobilize antibody CEA (anti-CEA). Finally, bovine serum albumin (BSA) was employed to block sites against nonspecific binding. In our study, cyclic voltammetry (CV) and scanning electron microscopy (SEM) were used to characterize the fabricated process of the immunosensor. The immunosensor put up a rapid response time, high sensitivity and stability. Under the optimized conditions, cyclic voltammograms(CVs) determination of CEA displayed a broader linear response to CEA in two ranges, from 0.25 to 8.0 ng/mL, and from 8.0 to 100 ng/mL, with a relative low-detection limit of 0.083 ng/mL at three times the background and noise. The originality of the preparation of the immunosensor lies in not only using the synergistic effect of two kinds of nanomaterials (nano-MnO(2) and nano-Au) to immobilize anti-CEA, but also using nano-MnO(2) + CS to furnish a media transferring electron path. What is more, the researched methodology was efficient and potentially attractive for clinical immunoassays. PMID:18923847

Ling, Shujuan; Yuan, Ruo; Chai, Yaqin; Zhang, Tingting

2008-10-16

159

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

160

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

161

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

162

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

163

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

164

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

165

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...

166

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

167

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

168

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

169

High-efficient treatment of wastewater contained the carcinogen naphthylamine by electrochemical oxidation with ?-Al2O3 supported MnO2 and Sb-doped SnO2 catalyst.  

PubMed

1-Naphthylamine wastewater causes severe environmental pollution because of its acute toxicity and carcinogenicity in humans, which makes it difficult to reuse by conventional technologies. In this study, we report an investigation of the electrochemical catalytic oxidation of 1-naphthylamine in synthetic wastewater in a 150 mL electrolytic batch reactor with Ti/Sb-SnO(2)/PbO(2) as anode and steel plate as cathode, where the reaction was assisted by MnO(2) and Sn(1-x)Sb(x)O(2) composite materials as the catalyst and ?-Al(2)O(3) as the carrier (MnO(2)-Sn(1-x)Sb(x)O(2)/?-Al(2)O(3)). The catalyst was synthesized by impregnating process and was characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The effects of pH and current density on the efficiency of the electrochemical degradation process were also studied. It was found that MnO(2)-Sn(1-x)Sb(x)O(2)/?-Al(2)O(3) exhibited excellent catalytic activity in the electrochemical degradation of 1-naphthylamine wastewater. The results showed that the refractory organics in wastewater can be effectively removed by this process, and a chemical oxygen demand (COD) removal efficiency of 92.2% was obtained in 20 min at pH 7.0 and current density was equal to 50 mA cm(-2). According to the experimental results, a hypothetical mechanism of electrochemical catalytic degradation was also proposed. PMID:22652320

Chen, Fengtao; Yu, Sanchuan; Dong, Xiaoping; Zhang, Shishen

2012-05-14

170

Magnetic bioactive glass ceramic in the system CaO–P 2 O 5 –SiO 2 –MgO–CaF 2 –MnO 2 –Fe 2 O 3 for hyperthermia treatment of bone tumor  

Microsoft Academic Search

Magnetic bioactive glass ceramic (MG) in the system CaO–SiO2–P2O5–MgO–CaF2–MnO2–Fe2O3 for hyperthermia treatment of bone tumor was synthesized. The phase composition was investigated by XRD. The magnetic property\\u000a was measured by VSM. The in vitro bioactivity was investigated by simulated body fluid (SBF) soaking experiment. Cell growth\\u000a on the surface of the material was evaluated by co-culturing osteoblast-like ROS17\\/2.8 cells with

Guangda Li; Shuying Feng; Dali Zhou

171

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

172

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

173

Improved cycling performance of bismuth-modified amorphous manganese oxides as cathodes for rechargeable lithium batteries  

Microsoft Academic Search

Bismuth-modified amorphous manganese oxides were synthesized via a room temperature aqueous route. They were galvanostatically tested as intercalation cathodes for rechargeable lithium batteries at 1mAcm?2 between 1.5 and 4.3V. In sharp contrast to severe capacity fading of unmodified amorphous manganese oxide synthesized by the same route, a stable cycling performance of the bismuth-modified amorphous manganese oxide was observed. After an

Jingsi Yang; Terrill B Atwater; Jun John Xu

2005-01-01

174

What is the limiting factor of the cycle-life of Zn–polyaniline rechargeable batteries?  

Microsoft Academic Search

The factors affecting the cycle-life of Zn–polyaniline (PANI) rechargeable batteries are studied by means of electrochemical and surface analyses of electrodes. The PANI polymeric film is prepared by cyclic voltammetery in an aqueous solution, and is tested as the positive electrode (cathode) of a secondary battery containing a 1.0M ZnCl2 and 0.5M NH4Cl electrolyte. The battery is charged and discharged

M. S Rahmanifar; M. F Mousavi; M Shamsipur; M Ghaemi

2004-01-01

175

Rechargeable lithium\\/polymer cathode batteries. Technical report, July 1988June 1989  

Microsoft Academic Search

Polypyrrole (PPy) and polyaniline (PAn) were investigated for cathode materials of rechargeable lithium batteries. PPy films prepared with PF6(-) anion and\\/or Platinum substrate precoated with nitrile butadiene rubber(NBR) were excellent cathode materials because of rough and\\/or highly oriented film structure. PAn films were successfully prepared from non-aqueous propylene carbonate solution containing aniline, CFâCOOH and lithium perchlorate. Its acidity strongly affects

T. Osaka; T. Nakajima; K. Shiota; B. B. Owens

1989-01-01

176

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

177

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)...

178

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

179

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

180

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

181

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

182

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

183

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

184

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

185

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

186

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

187

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

188

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

189

Doped lanthanum nickelates with a layered perovskite structure as bifunctional cathode catalysts for rechargeable metal-air batteries.  

PubMed

Rechargeable metal-air batteries have attracted a great interest in recent years because of their high energy density. The critical challenges facing these technologies include the sluggish kinetics of the oxygen reduction-evolution reactions on a cathode (air electrode). Here, we report doped lanthanum nickelates (La2NiO4) with a layered perovskite structure that serve as efficient bifunctional electrocatalysts for oxygen reduction and evolution in an aqueous alkaline electrolyte. Rechargeable lithium-air and zinc-air batteries assembled with these catalysts exhibit remarkably reduced discharge-charge voltage gaps (improved round-trip efficiency) as well as high stability during cycling. PMID:24053465

Jung, Kyu-Nam; Jung, Jong-Hyuk; Im, Won Bin; Yoon, Sukeun; Shin, Kyung-Hee; Lee, Jong-Won

2013-09-23

190

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

191

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

192

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

193

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

194

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

195

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

196

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

197

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

198

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

199

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

200

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

201

Rechargeable 3 V Li cells using hydrated lamellar manganese oxide  

SciTech Connect

The synthesis and the electrochemical features of hydrated lamellar manganese oxides are reported. The authors use the reduction of aqueous permanganate solution by fumaric acid and the oxidation of manganese hydroxide by an aqueous permanganate solution to obtain sol-gel birnessite and classical X-exchanged birnessites (X = Li, Al, Na), respectively. The high oxidation state of Mn associated with the 2D character of the hot lattice allows high specific capacities (150 to 200 Ah/kg) available in the potential range of 4 to 2 V. Interlayer water provides the structural stability of the host lattice required for long cycling. Rechargeable two-electrode Li cells using starved or flooded electrolytes were built with the cathodic materials. The batteries exhibit a satisfactory behavior with a specific capacity of 160 Ah/kg recovered after 30 cycles at the C/20 discharge-charge rate for the sol-gel birnessite. This paper demonstrates an interest in cathodic materials based on oxides containing structural water for use in secondary Li batteries.

Bach, S.; Pereira-Ramos, J.P. [CNRS, Thiais (France). Electrochimie, Catalyse et Synthese Organique; Baffier, N. [CNRS, Paris (France). Chimie Appliquee de l`Etat Solide

1996-11-01

202

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

203

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

204

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

205

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

206

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

207

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

208

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

209

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

210

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

211

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

212

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

213

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

214

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

215

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...

216

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

217

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

218

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

219

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

220

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

221

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

222

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

223

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

224

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

225

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

226

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

227

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

228

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

229

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

230

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

231

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

232

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

233

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

234

Rechargeable lithium/polymer cathode batteries. Technical report, July 1988-June 1989  

SciTech Connect

Polypyrrole (PPy) and polyaniline (PAn) were investigated for cathode materials of rechargeable lithium batteries. PPy films prepared with PF6(-) anion and/or Platinum substrate precoated with nitrile butadiene rubber(NBR) were excellent cathode materials because of rough and/or highly oriented film structure. PAn films were successfully prepared from non-aqueous propylene carbonate solution containing aniline, CF{sub 3}COOH and lithium perchlorate. Its acidity strongly affects the anion doping-undoping behavior. The Pan cathode prepared in high acidic solution (e.g. 4:1 ratio of acid:aniline) gives the excellent battery performance.

Osaka, T.; Nakajima, T.; Shiota, K.; Owens, B.B.

1989-06-15

235

Lithium-ion rechargeable cells with LiCoO2 and carbon electrodes  

NASA Astrophysics Data System (ADS)

Cathodes composed of layered transition metal oxides LiMO2 (M = Co, Ni) and spinel manganese oxide LiMn2O4, carbon anodes, and non aqueous electrolyte solutions have been investigated with the aim of achieving higher energy density. The lithium-ion rechargeable cell using the LiCoO2 cathode and the propylene carbonate(PC)-d iethyl carbonate (DEC)/LiPF6) electrolyte solution exhibits excellent characteristics. Furthermore, non-graphitizable carbon such as polyfurfuryl alcohol derived carbon has larger capacity and better cycleability than graphitizable carbon such as coke.

Sekai, K.; Azuma, H.; Omaru, A.; Fujita, S.; Imoto, H.; Endo, T.; Yamaura, K.; Nishi, Y.; Mashiko, S.; Yokogawa, M.

1993-03-01

236

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

237

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

238

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

239

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

240

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

241

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

242

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

243

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

244

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

245

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

246

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

247

Magnetic bioactive glass ceramic in the system CaO-P2O5-SiO2-MgO-CaF2-MnO2-Fe2O3 for hyperthermia treatment of bone tumor.  

PubMed

Magnetic bioactive glass ceramic (MG) in the system CaO-SiO(2)-P(2)O(5)-MgO-CaF(2)-MnO(2)-Fe(2)O(3) for hyperthermia treatment of bone tumor was synthesized. The phase composition was investigated by XRD. The magnetic property was measured by VSM. The in vitro bioactivity was investigated by simulated body fluid (SBF) soaking experiment. Cell growth on the surface of the material was evaluated by co-culturing osteoblast-like ROS17/2.8 cells with materials for 7 days. The results showed that MG contained CaSiO(3) and Ca(5)(PO(4))(3)F as the main phases, and MnFe(2)O(4) and Fe(3)O(4) as the magnetic phases. Under a magnetic field of 10,000 Oe, the saturation magnetization and coercive force of MG were 6.4 emu/g and 198 Oe, respectively. After soaking in SBF for 14 days, hydroxyapatite containing CO(3)(2-) was observed on the surface of MG. The experiment of co-culturing cells with material showed that cells could successfully attach and well proliferate on MG. PMID:21870083

Li, Guangda; Feng, Shuying; Zhou, Dali

2011-08-26

248

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

249

Piezoelectric properties of MnO 2 doped low temperature sintering Pb(Mn 1\\/3 Nb 2\\/3 )O 3 –Pb(Ni 1\\/3 Nb 2\\/3 )O 3 –Pb(Zr 0.50 Ti 0.50 )O 3 ceramics  

Microsoft Academic Search

In this study, in order to develop the composition ceramics for low loss and low temperature sintering multilayer piezoelectric\\u000a actuator, Pb(Mn1\\/3Nb2\\/3)O3–Pb(Ni1\\/3Nb2\\/3)O3–Pb(Zr0.50Ti0.50)O3 (abbreviated as PMN-PNN-PZT) ceramics were fabricated using Li2CO3 and Na2CO3 as sintering aids, and their piezoelectric and dielectric characteristics were investigated according to the amount of MnO2 addition. At the 0.2 wt% MnO2 doped specimen sintered at 900 °C, density and

Juhyun Yoo; Sangho Lee

2009-01-01

250

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

251

Lattice vibrations of materials for lithium rechargeable batteries III. Lithium manganese oxides  

Microsoft Academic Search

Structural features of several lithiated manganese oxides are studied using Raman scattering (RS) spectroscopy. This local probe is capable to analyse directly the near-neighbour environment of oxygen coordination around manganese and lithium cations. The samples include: orthorhombic and monoclinic LiMnO2, spinel LiMn2O4, monoclinic Li2MnO3, lithiated-spinel Li2Mn2O4, Li-birnessite, LT- and HT-Li0.52MnO2.1, spinel Li4Mn5O12, and Li0.33MnO2. Thus, as a first approach, we

C. M. Julien; M. Massot

2003-01-01

252

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

253

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

254

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

255

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

256

Determination of radium-226 in aqueous solutions by alpha-spectrometry.  

PubMed

The new European legislation imposes a lower threshold for radioactivity in drinking water. This requires the development of more sensitive and reliable analytical methods. This work presents an improved alpha-spectrometric technique to determine the radium-226 activity in aqueous solution relying on the radium adsorption onto a thin manganese oxide layer followed by alpha-measurement. The preparation of the MnO2 deposit has been optimized as well as the radium adsorption conditions. Detection threshold and limit of 5 and 10 mBq x L(-1), respectively, with a 10% (95% confidence) uncertainty are currently reached. This paper reports on the overall technique and on its application to assess the radium-226 activity in 28 French mineral waters. In addition, the gross alpha- and beta-activities have been evaluated using proportional counting while the uranium concentrations were derived from ICPMS. PMID:11569812

Morvan, K; Andres, Y; Mokili, B; Abbe, J C

2001-09-01

257

Ceria based catalyst for cathode in non-aqueous electrolyte based Li/O2 batteries  

NASA Astrophysics Data System (ADS)

This study suggests combustion synthesized Ce1-xZrxO2 (CZO; x = 0.1-0.5) as a new catalyst for the cathode in non-aqueous electrolyte based Li/O2 cells. The spherical catalysts have a fluorite structure with a mean diameter of 5-17 nm. Zr doping into the ceria lattice leads to the reduction of Ce4+ to Ce3+, which further improves the catalyst performance. Electrochemical studies of CZO as a cathode catalyst in the Li/O2 cell show that CZO follows a two-electron pathway for oxygen reduction. A maximum discharge capacity of 1620 mAh g-1 is obtained for the Ce0.8Zr0.2O2 catalyst due to its high surface area and porosity. A composite of CZO and MnO2 shows even better performance as a cathode catalyst for the Li/O2 cell.

Kalubarme, Ramchandra S.; Cho, Min-Seung; Kim, Jae-Kook; Park, Chan-Jin

2012-11-01

258

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

259

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

260

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

261

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

262

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

263

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

264

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

265

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

266

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

267

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

268

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

269

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

270

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

271

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

272

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

273

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

274

[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

275

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

276

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

277

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

278

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

279

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

280

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

281

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

282

A new NASICON-type polyanion, Li x Ni 2(MoO 4) 3 as 3-V class positive electrode material for rechargeable lithium batteries  

Microsoft Academic Search

This paper presents our success in synthesizing a new framework type LixNi2(MoO4)3 (0?x?4) polyanion compound by adopting a novel aqueous soft-combustion process. The annealed powders exhibited a single-phase structure as confirmed by X-ray diffraction (XRD) and were characterized by electrochemical techniques in order to elucidate the suitability of this new material as positive electrode material in rechargeable lithium-containing batteries. The

K. M. Begam; Y. H. Taufiq-Yap; M. S. Michael; S. R. S. Prabaharan

2004-01-01

283

Oxidative removal of aqueous steroid estrogens by manganese oxides  

Microsoft Academic Search

This study investigated the oxidative removal of steroid estrogens from water by synthetic manganese oxide (MnO2) and the factors influencing the reactions. Using 1×10?5M MnO2 at pH 4, estrone (E1), 17?-estradiol (E2), estriol (E3) and 17?-ethinylestradiol (EE2), all at 4×10?6M, were rapidly removed within 220min, indicating the effectiveness of MnO2 as an oxidizing agent towards estrogens. E2 removal increased with

Lei Xu; Chao Xu; Meirong Zhao; Yuping Qiu; G. Daniel Sheng

2008-01-01

284

Electrochemical behavior of LiCoO 2 as aqueous lithium-ion battery electrodes  

Microsoft Academic Search

Despite the large number of studies on the behavior of LiCoO2 in organic electrolytes and its recent application as a positive electrode in rechargeable water battery prototypes, a little information is available about the lithium intercalation reaction in this layered compound in aqueous electrolytes. This work shows that LiCoO2 electrodes can be reversibly cycled in LiNO3 aqueous electrolytes for tens

Riccardo Ruffo; Colin Wessells; Robert A. Huggins; Yi Cui

2009-01-01

285

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

286

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 ...

287

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

288

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

289

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

290

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

291

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

292

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

293

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

294

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

295

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

296

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

297

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

298

Layer cathode methods of manufacturing and materials for Li-ion rechargeable batteries  

DOEpatents

A positive electrode active material for lithium-ion rechargeable batteries of general formula Li.sub.1+xNi.sub..alpha.Mn.sub..beta.A.sub..gamma.O.sub.2 and further wherein A is Mg, Zn, Al, Co, Ga, B, Zr, or Ti and 0aqueous solution method or a sol-gel method which is followed by a rapid quenching from high temperatures into liquid nitrogen or liquid helium.

Kang, Sun-Ho (Naperville, IL); Amine, Khalil (Downers Grove, IL)

2008-01-01

299

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

300

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

301

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

302

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

303

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.

304

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

305

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

306

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

307

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

308

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

309

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

310

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...

311

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...

312

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

313

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

314

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

315

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

316

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

317

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

318

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

319

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

320

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

321

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

322

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 ...

323

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...

324

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...

325

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

326

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

327

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

328

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

329

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

330

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

331

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

332

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

333

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

334

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

335

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...

336

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

337

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

338

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

339

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

340

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

341

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

342

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

343

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

344

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

345

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

346

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

347

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

348

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

349

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

350

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

351

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

352

Preparation of polyaniline nanofibers and their use as a cathode of aqueous rechargeable batteries  

Microsoft Academic Search

Normal pulse voltammetric method was used to synthesize nanofibers of polyaniline (PANi) in HCl solution on a platinum electrode. The influences of the synthesis parameters, such as potential increment, pulse duration and monomer concentration on the electrochemical properties of the PANi films were investigated. Scanning electron microscopic micrographs clearly revealed the formation a nanofiber structure with average diameter in range

Kh. Ghanbari; M. F. Mousavi; M. Shamsipur

2006-01-01

353

The development and challenges of rechargeable non-aqueous lithium–air batteries  

Microsoft Academic Search

Lithium–air (Li–air) batteries have recently received much attention due to their extremely high theoretical energy densities. The significantly larger theoretical energy density of Li–air batteries is due to the use of a pure lithium metal anode and the fact that the cathode oxidant, oxygen, is stored externally since it can be readily obtained from the surrounding air. However, before Li–air

Lei-Lei Zhang; Zhong-Li Wang; Dan Xu; Xin-Bo Zhang; Li-Min Wang

2012-01-01

354

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

355

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

356

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

357

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

358

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

359

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

360

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

361

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

362

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

363

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

364

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

365

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

366

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.

367

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

368

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

369

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

370

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

371

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

372

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

373

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

374

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

375

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

376

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

377

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

378

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

379

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

380

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

381

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

382

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

383

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

384

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

385

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

386

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

387

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

388

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

389

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

390

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

391

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

392

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

393

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

394

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

395

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

396

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

397

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

398

Lithium Ion Aqueous Cells.  

National Technical Information Service (NTIS)

Lithium ion aqueous cells were investigated using lithium intercalating compounds as anodes and cathodes. The aqueous electrolyte consisted of 4 to 5 molar solutions of either lithium perchlorate or lithium nitrate which contained lithium hydroxide in mil...

E. J. Plichta W. K. Behl

1995-01-01

399

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

400

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

401

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

402

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

403

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

404

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

405

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

406

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

407

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

408

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

409

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

410

Synthesis and characterization of nanostructured cathode materials for rechargeable lithium/lithium ion batteries  

NASA Astrophysics Data System (ADS)

The rapidly increasing markets of portable electronic devices and electric/hybrid vehicles have raised worldwide R&D efforts in developing high-energy rechargeable lithium and lithium ion batteries. High performance intercalation cathodes are key to the success of these batteries. The nanotechnology has endowed the electrode materials with a variety of improved features as well as unique characteristics. Synthesis approaches were designed in this thesis work to utilize these advantages and investigate the exceptional phenomena raised by the nanostructured materials. A novel sol-gel method was designed for the synthesis of carbon-coated phase-pure lithium iron phosphate with submicron particle sizes and uniform size distribution. The surface carbon coating was formed in-situ through pyrolysis of the precursor gel, which improved the apparent electronic conductivity of the as prepared material to 10-2 S/cm compared with 10-9-10-10 S/cm of the pristine LiFePO 4. The favorable physical characteristics of the synthesized LiFePO 4 particles and the improved electronic conductivity through the carbon coating led to electrochemical properties comparable to the best performances reported so far. Amorphous manganese oxide cryogels with nanoarchitecture were obtained by freeze-drying Mn (IV) oxide hydrogels. The combination of the advantages of the amorphous structure and the nano-architecture of the materials gave high capacities and excellent rate capabilities. This work led to the finding of a nanocrystalline Li2MnO3-like compound with a surprising electrochemical activity, which is in sharp contrast to the microcrystalline rock-salt Li2MnO3 that has been known to be electrochemically inactive. The study highlights the possibility of qualitative difference in intercalation behavior of nanostructured intercalation compounds compared with their microcrystalline counterparts. Bismuth and copper modified amorphous manganese oxides were synthesized by aqueous coprecipitation methods and investigated as intercalation hosts for rechargeable lithium batteries. The results suggest the promise of achieving high performance intercalation electrodes by enhancing amorphous manganese oxides through cation modification.

Yang, Jingsi

411

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

412

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

413

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

414

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

415

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

416

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

417

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

418

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

419

Improved discharge characteristics of tunnel-containing manganese oxide electrodes for rechargeable lithium battery applications  

SciTech Connect

LixMnO2 made from Na0.44MnO2 has an unusual tunnel structure which allows ion insertion processes to occur with minimal strain. It cycles very reversibly at an average voltage of about 3.2 vs. Li without undergoing phase conversion. The stability of this material makes it a promising candidate for use in electric vehicle applications, which not only have severe cost constraints, but also require long cycle life and abuse-tolerance. In practical lithium cells, however, the demonstrated capacity is typically less than the predicted 200 mAh/g for LixMnO2 cathode materials made by conventional solid-state reactions. This is due to kinetic limitations and to the sloping discharge characteristics. Attritor-milling of conventionally-made LixMnO2 and glycine-nitrate combustion synthesis have been used to produce powders with average particle size below 1 mm, improved rate capability, and a 15 percent improvement in utilization. Up to 55 percent of the Mn in LixMnO2 with the Na0.44MnO2 structure can also be replaced with Ti. Ti-doped analogs have modified discharge characteristics, with some exhibiting better utilization between set voltage limits than the parent compound.

Doeff, Marca M.; Richardson, Thomas J.; Hwang, Kwang-Taek; Anapolsky, Abraham

2000-05-01

420

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

421

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

422

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

423

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...

424

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

425

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

426

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

427

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

428

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

429

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

430

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

431

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

432

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

433

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

434

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

435

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

436

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

437

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...

438

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

439

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

440

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

441

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

442

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

443

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

444

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

445

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

446

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

447

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

448

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

449

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

450

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....

451

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

452

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

453

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

454

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

455

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

456

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

457

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 V5