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We encourage you to perform a real-time search of NLEBeta
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1

Ion transport through cell membrane channels  

E-Print Network [OSTI]

We discuss various models of ion transport through cell membrane channels. Recent experimental data shows that sizes of ion channels are compared to those of ions and that only few ions may be simultaneously in any single channel. Theoretical description of ion transport in such channels should therefore take into account interactions between ions and between ions and channel proteins. This is not satisfied by macroscopic continuum models based on Poisson-Nernst-Planck equations. More realistic descriptions of ion transport are offered by microscopic Brownian and molecular dynamics. One should also take into account a dynamical character of the channel structure. This is not yet addressed in the literature

Jan Gomulkiewicz; Jacek Miekisz; Stanislaw Miekisz

2007-06-05T23:59:59.000Z

2

Ion transport membrane module and vessel system  

SciTech Connect (OSTI)

An ion transport membrane system comprising (a) a pressure vessel having an interior, an exterior, an inlet, and an outlet; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein any inlet and any outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; and (c) one or more gas manifolds in flow communication with interior regions of the membrane modules and with the exterior of the pressure vessel. The ion transport membrane system may be utilized in a gas separation device to recover oxygen from an oxygen-containing gas or as an oxidation reactor to oxidize compounds in a feed gas stream by oxygen permeated through the mixed metal oxide ceramic material of the membrane modules.

Stein, VanEric Edward (Allentown, PA); Carolan, Michael Francis (Allentown, PA); Chen, Christopher M. (Allentown, PA); Armstrong, Phillip Andrew (Orefield, PA); Wahle, Harold W. (North Canton, OH); Ohrn, Theodore R. (Alliance, OH); Kneidel, Kurt E. (Alliance, OH); Rackers, Keith Gerard (Louisville, OH); Blake, James Erik (Uniontown, OH); Nataraj, Shankar (Allentown, PA); Van Doorn, Rene Hendrik Elias (Obersulm-Willsbach, DE); Wilson, Merrill Anderson (West Jordan, UT)

2012-02-14T23:59:59.000Z

3

Ion transport membrane module and vessel system  

DOE Patents [OSTI]

An ion transport membrane system comprising (a) a pressure vessel having an interior, an exterior, an inlet, and an outlet; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein any inlet and any outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; and (c) one or more gas manifolds in flow communication with interior regions of the membrane modules and with the exterior of the pressure vessel.The ion transport membrane system may be utilized in a gas separation device to recover oxygen from an oxygen-containing gas or as an oxidation reactor to oxidize compounds in a feed gas stream by oxygen permeated through the mixed metal oxide ceramic material of the membrane modules.

Stein, VanEric Edward (Allentown, PA); Carolan, Michael Francis (Allentown, PA); Chen, Christopher M. (Allentown, PA); Armstrong, Phillip Andrew (Orefield, PA); Wahle, Harold W. (North Canton, OH); Ohrn, Theodore R. (Alliance, OH); Kneidel, Kurt E. (Alliance, OH); Rackers, Keith Gerard (Louisville, OH); Blake, James Erik (Uniontown, OH); Nataraj, Shankar (Allentown, PA); van Doorn, Rene Hendrik Elias (Obersulm-Willsbach, DE); Wilson, Merrill Anderson (West Jordan, UT)

2008-02-26T23:59:59.000Z

4

Liners for ion transport membrane systems  

SciTech Connect (OSTI)

Ion transport membrane system comprising (a) a pressure vessel comprising an interior, an exterior, an inlet, an inlet conduit, an outlet, and an outlet conduit; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein the inlet and the outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; (c) a gas manifold having an interior surface wherein the gas manifold is in flow communication with the interior region of each of the planar ion transport membrane modules and with the exterior of the pressure vessel; and (d) a liner disposed within any of the inlet conduit, the outlet conduit, and the interior surface of the gas manifold.

Carolan, Michael Francis (Allentown, PA); Miller, Christopher Francis (Macungie, PA)

2010-08-10T23:59:59.000Z

5

Ion Transport Through Cell Membrane Channels Jan Gomulkiewicz1  

E-Print Network [OSTI]

1 Ion Transport Through Cell Membrane Channels Jan Gomulkiewicz1 , Jacek Mikisz2 , and Stanislaw various models of ion transport through cell membrane channels. Recent experimental data shows that sizes for the life of a cell. In particular, a fundamental phenomenon is a transport of ions through cell membranes

Miekisz, Jacek

6

Fabrication of catalyzed ion transport membrane systems  

DOE Patents [OSTI]

Process for fabricating a catalyzed ion transport membrane (ITM). In one embodiment, an uncatalyzed ITM is (a) contacted with a non-reducing gaseous stream while heating to a temperature and for a time period sufficient to provide an ITM possessing anion mobility; (b) contacted with a reducing gaseous stream for a time period sufficient to provide an ITM having anion mobility and essentially constant oxygen stoichiometry; (c) cooled while contacting the ITM with the reducing gaseous stream to provide an ITM having essentially constant oxygen stoichiometry and no anion mobility; and (d) treated by applying catalyst to at least one of (1) a porous mixed conducting multicomponent metallic oxide (MCMO) layer contiguous with a first side of a dense layer of MCMO and (2) a second side of the dense MCMO layer. In another embodiment, these steps are carried out in the alternative order of (a), (d), (b), and (c).

Carolan, Michael Francis; Kibby, Charles Leonard

2013-06-04T23:59:59.000Z

7

Feed gas contaminant removal in ion transport membrane systems  

SciTech Connect (OSTI)

An oxygen ion transport membrane process wherein a heated oxygen-containing gas having one or more contaminants is contacted with a reactive solid material to remove the one or more contaminants. The reactive solid material is provided as a deposit on a support. The one or more contaminant compounds in the heated oxygen-containing gas react with the reactive solid material. The contaminant-depleted oxygen-containing gas is contacted with a membrane, and oxygen is transported through the membrane to provide transported oxygen.

Underwood, Richard Paul (Allentown, PA); Makitka, III, Alexander (Hatfield, PA); Carolan, Michael Francis (Allentown, PA)

2012-04-03T23:59:59.000Z

8

Electrochemical control of ion transport through a mesoporous carbon membrane  

SciTech Connect (OSTI)

The transport of fluids through nanometer scale channels typically on the order of 1 -100 nm often exhibit unique properties compared to the bulk fluid. These phenomena occur because the channel dimensions and molecular size become comparable to the range of several important forces including electrostatic and van der Waals forces. Small changes in properties such as the electric double layer or surface charge can significantly affect molecular transport through the channels. Based on these emerging properties, a variety of nanofluidic devices such as nanofluidic transistors, nanofluidic diodes or lab-on-a-chip devices have been developed3-7 with a diverse range of applications including water purification, biomolecular sensing, DNA separation, and rectified ion transport. Nanofluidic devices are typically fabricated using expensive lithography techniques or sacrificial templates. Here we report a carbon-based, three-dimensional nanofluidic transport membrane that enables gated, or on/off, control of the transport of organic molecular species and metal ions using an applied electrical potential. In the absence of an applied potential, both cationic and anionic molecules freely diffuse across the membrane via a concentration gradient. However, when an electrochemical potential is applied, the transport of ions through the membrane is inhibited.

Surwade, Sumedh P [ORNL] [ORNL; Chai, Songhai [ORNL] [ORNL; Choi, Jai-Pil [ORNL] [ORNL; Wang, Xiqing [ORNL] [ORNL; Lee, Jeseung [ORNL] [ORNL; Vlassiouk, Ivan V [ORNL] [ORNL; Mahurin, Shannon Mark [ORNL] [ORNL; Dai, Sheng [ORNL] [ORNL

2014-01-01T23:59:59.000Z

9

Feed gas contaminant control in ion transport membrane systems  

DOE Patents [OSTI]

Ion transport membrane oxidation system comprising an enclosure having an interior and an interior surface, inlet piping having an internal surface and adapted to introduce a heated feed gas into the interior of the enclosure, and outlet piping adapted to withdraw a product gas from the interior of the enclosure; one or more planar ion transport membrane modules disposed in the interior of the enclosure, each membrane module comprising mixed metal oxide material; and a preheater adapted to heat a feed gas to provide the heated feed gas to the inlet piping, wherein the preheater comprises an interior surface. Any of the interior surfaces of the enclosure, the inlet piping, and the preheater may be lined with a copper-containing metal lining. Alternatively, any of the interior surfaces of the inlet piping and the preheater may be lined with a copper-containing metal lining and the enclosure may comprise copper.

Carolan, Michael Francis (Allentown, PA); Minford, Eric (Laurys Station, PA); Waldron, William Emil (Whitehall, PA)

2009-07-07T23:59:59.000Z

10

Experimental characterization of an Ion Transport Membrane (ITM) reactor for methane oxyfuel combustion  

E-Print Network [OSTI]

Ion Transport Membranes (ITM) which conduct both electrons and oxygen ions have been investigated experimentally for oxygen separation and fuel (mostly methane) conversion purposes over the last three decades. The fuel ...

Apo, Daniel Jolomi

2012-01-01T23:59:59.000Z

11

Numerical simulations of ion transport membrane oxy-fuel reactors for CO? capture applications  

E-Print Network [OSTI]

Numerical simulations were performed to investigate the key features of oxygen permeation and hydrocarbon conversion in ion transport membrane (ITM) reactors. ITM reactors have been suggested as a novel technology to enable ...

Hong, Jongsup

2013-01-01T23:59:59.000Z

12

Systems-level design of ion transport membrane oxy-combustion power plants  

E-Print Network [OSTI]

Oxy-fuel combustion, particularly using an integrated oxygen ion transport membrane (ITM), is a thermodynamically attractive concept that seeks to mitigate the penalties associated with CO 2 capture from power plants. ...

Mancini, Nicholas D. (Nicholas David)

2011-01-01T23:59:59.000Z

13

Ion transport membrane module and vessel system with directed internal gas flow  

DOE Patents [OSTI]

An ion transport membrane system comprising (a) a pressure vessel having an interior, an inlet adapted to introduce gas into the interior of the vessel, an outlet adapted to withdraw gas from the interior of the vessel, and an axis; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region; and (c) one or more gas flow control partitions disposed in the interior of the pressure vessel and adapted to change a direction of gas flow within the vessel.

Holmes, Michael Jerome (Thompson, ND); Ohrn, Theodore R. (Alliance, OH); Chen, Christopher Ming-Poh (Allentown, PA)

2010-02-09T23:59:59.000Z

14

Quantitative description of ion transport via plasma membrane of yeast and small cells  

E-Print Network [OSTI]

Modelling of ion transport via plasma membrane needs identification and quantitative understanding of the involved processes. Brief characterisation of ion transport systems of a yeast cell (Pma1, Ena1, TOK1, Nha1, Trk1, Trk2, non-selective cation conductance) and estimates concerning the number of molecules of each transporter per a cell allow predicting the corresponding ion flows. Comparison of ion transport in small yeast cell and several animal cell types is provided and importance of cell volume to surface ratio is stressed. Role of cell wall and lipid rafts is discussed in aspect of required increase in spatial and temporary resolution of measurements. Conclusions are formulated to describe specific features of ion transport in a yeast cell. Potential directions of future research are outlined based on the assumptions.

Volkov, Vadim

2012-01-01T23:59:59.000Z

15

Quantitative description of ion transport via plasma membrane of yeast and small cells  

E-Print Network [OSTI]

Modelling of ion transport via plasma membrane needs identification and quantitative understanding of the involved processes. Brief characterisation of ion transport systems of a yeast cell (Pma1, Ena1, TOK1, Nha1, Trk1, Trk2, non-selective cation conductance) and estimates concerning the number of molecules of each transporter per a cell allow predicting the corresponding ion flows. Comparison of ion transport in small yeast cell and several animal cell types is provided and importance of cell volume to surface ratio is stressed. Role of cell wall and lipid rafts is discussed in aspect of required increase in spatial and temporary resolution of measurements. Conclusions are formulated to describe specific features of ion transport in a yeast cell. Potential directions of future research are outlined based on the assumptions.

Vadim Volkov

2012-12-18T23:59:59.000Z

16

Thorium ions transport across Tri-n-butyl phosphate-benzene based supported liquid membranes  

SciTech Connect (OSTI)

Transport of Th(IV) ions across tri-n-butyl phosphate (TBP) benzene based liquid membranes supported in microporous hydrophobic polypropylene film (MHPF) has been studied. Various parameters such as variation of nitric acid concentration in the feed, TBP concentration in the membrane, and temperature on the given metal ions transport have been investigated. The effects of nitric acid and TBP concentrations on the distribution coefficient were also studied, and the data obtained were used to determine the Th ions-TBP complex diffusion coefficient in the membrane. Permeability coefficients of Th(IV) ions were also determined as a function of the TBP and nitric acid concentrations. The optimal conditions for the transport of Th(IV) ions across the membrane are 6 mol{sm_bullet}dm{sup -3} HNO{sub 3} concentration, 2.188 mol {center_dot} dm{sup -3} TBP concentration, and 25{degrees}C. The stoichiometry of the chemical species involved in chemical reaction during the transport of Th(IV) ions has also been studied.

Rasul, G.; Chaudry, M.A. [Pakistan Institute of Nuclear Chemistry, Islamabad (Pakistan); Afzal, M. [Quaid-I-Azam Univ., Islamabad (Pakistan)

1995-12-01T23:59:59.000Z

17

Cathode and electrolyte materials for solid oxide fuel cells and ion transport membranes  

DOE Patents [OSTI]

Novel cathode, electrolyte and oxygen separation materials are disclosed that operate at intermediate temperatures for use in solid oxide fuel cells and ion transport membranes based on oxides with perovskite related structures and an ordered arrangement of A site cations. The materials have significantly faster oxygen kinetics than in corresponding disordered perovskites.

Jacobson, Allan J; Wang, Shuangyan; Kim, Gun Tae

2014-01-28T23:59:59.000Z

18

Transport Modeling of Membrane Extraction of Chlorinated Hydrocarbon from Water for Ion Mobility Spectrometry  

SciTech Connect (OSTI)

Membrane-extraction Ion Mobility Spectrometry (ME-IMS) is a feasible technique for the continuous monitoring of chlorinated hydrocarbons in water. This work studies theoretically the time-dependent characteristics of sampling and detection of trichloroethylene (TCE). The sampling is configured so that aqueous contaminants permeate through a hollow polydimethylsiloxane (PDMS) membrane and are carried away by a transport gas flowing through the membrane tube into IMS analyzer. The theoretical study is based on a two-dimensional transient fluid flow and mass transport model. The model describes the TCE mixing in the water, permeation through the membrane layer, and convective diffusion in the air flow inside membrane tube. The effect of various transport gas flow rates on temporal profiles of IMS signal intensity is investigated. The results show that fast time response and high transport yield can be achieved for ME-IMS by controlling the flow rate in the extraction membrane tube. These modeled time-response profiles are important for determining duty cycles of field-deployable sensors for monitoring chlorinated hydrocarbons in water.

Zhang, Wei [ORNL; Du, Yongzhai [ORNL; Feng, Zhili [ORNL; Xu, Jun [ORNL

2010-01-01T23:59:59.000Z

19

FINAL REPORT:Observation and Simulations of Transport of Molecules and Ions Across Model Membranes  

SciTech Connect (OSTI)

During the this new grant we developed a robust methodology for investigating a wide range of properties of phospho-lipid bilayers. The approach developed is unique because despite using periodic boundary conditions, we can simulate an entire experiment or process in detail. For example, we can follow the entire permeation process in a lipid-membrane. This includes transport from the bulk aqueous phase to the lipid surface; permeation into the lipid; transport inside the lipid; and transport out of the lipid to the bulk aqueous phase again. We studied the transport of small gases in both the lipid itself and in model protein channels. In addition, we have examined the transport of nanocrystals through the lipid membrane, with the main goal of understanding the mechanical behavior of lipids under stress including water and ion leakage and lipid flip flop. Finally we have also examined in detail the deformation of lipids when under the influence of external fields, both mechanical and electrostatic (currently in progress). The important observations and conclusions from our studies are described in the main text of the report

MURAD, SOHAIL [University of Illinois at Chicago] [University of Illinois at Chicago; JAMESON, CYNTHIA J [University of Illinois at Chicago] [University of Illinois at Chicago

2013-10-22T23:59:59.000Z

20

Smart membranes for nitrate removal, water purification, and selective ion transportation  

DOE Patents [OSTI]

A computer designed nanoengineered membrane for separation of dissolved species. One embodiment provides an apparatus for treatment of a fluid that includes ions comprising a microengineered porous membrane, a system for producing an electrical charge across the membrane, and a series of nanopores extending through the membrane. The nanopores have a pore size such that when the fluid contacts the membrane, the nanopores will be in a condition of double layer overlap and allow passage only of ions opposite to the electrical charge across the membrane.

Wilson, William D. (Pleasanton, CA); Schaldach, Charlene M. (Pleasanton, CA); Bourcier, William L. (Livermore, CA); Paul, Phillip H. (Livermore, CA)

2009-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Membrane Transport Chloride Transport Across Vesicle and Cell  

E-Print Network [OSTI]

Membrane Transport Chloride Transport Across Vesicle and Cell Membranes by Steroid-Based Receptors-established that molecules which transport cations across cell membranes (cationophores) can have potent biological effects the formation of an ion pair.[4a­g] Anion transport by purely electroneutral systems is still quite rare.[4j

Smith, Bradley D.

22

Oxygen Transport Ceramic Membranes Quarterly Report  

E-Print Network [OSTI]

/Reaction rates in Ion 21 Transport Membranes using Isotope Tracer and Transient Kinetic Techniques CONCLUSIONS 30Oxygen Transport Ceramic Membranes Quarterly Report January 2003 ­ March 2003 Principal Authors on the thermodynamic properties of the membrane materials are continued to develop a complete model for the membrane

Eagar, Thomas W.

23

6 Ion Transport, Osmoregulation, and  

E-Print Network [OSTI]

177 6 Ion Transport, Osmoregulation, and Acid­Base Balance W.S. Marshall and M. Grosell CONTENTS I)............................................................................182 5. Skin and Opercular Membrane..................................................................................................183 2. Sea-Water Transport Mode -- Na+,K+-ATPase and Na+,K+, 2Cl­ Co-transport

Grosell, Martin

24

Journal of Membrane Science 239 (2004) 1726 Highly conductive ordered heterogeneous ion-exchange membranes  

E-Print Network [OSTI]

in the matrix required for reasonable ion transport through the membrane is 50­70 wt.% [2Journal of Membrane Science 239 (2004) 17­26 Highly conductive ordered heterogeneous ion-exchange membranes are used in electrodialysis (ED) as ion-selective membranes and in power sources (such as fuel

Freger, Viatcheslav "Slava"

25

OXYGEN TRANSPORT CERAMIC MEMBRANES  

SciTech Connect (OSTI)

This report covers the following tasks: Task 1--Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints; Task 2--Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability; Task 3--Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres; Task 4--Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures; Task 5--Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability; and Task 6--Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques.

Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

2002-04-01T23:59:59.000Z

26

Characterization of a plasma membrane zinc transporter in rat brain  

E-Print Network [OSTI]

Ireland Ltd. Keywords: Ion transport; Membrane vesicles; Excitotoxicity; Zinc homeostasis; TransitionCharacterization of a plasma membrane zinc transporter in rat brain Robert A. Colvin* Department transport in the brain. This report provides convincing evidence of a zinc transporter in plasma membrane

27

OXYGEN TRANSPORT CERAMIC MEMBRANES  

SciTech Connect (OSTI)

This is the third quarterly report on oxygen Transport Ceramic Membranes. In the following, the report describes the progress made by our university partners in Tasks 1 through 6, experimental apparatus that was designed and built for various tasks of this project, thermodynamic calculations, where applicable and work planned for the future. (Task 1) Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. (Task 2) Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability. (Task 3) Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres. (Task 4) Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures. (Task 5) Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability. (Task 6) Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques.

Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

2000-10-01T23:59:59.000Z

28

Hydrogen transport membranes  

DOE Patents [OSTI]

Composite hydrogen transport membranes, which are used for extraction of hydrogen from gas mixtures are provided. Methods are described for supporting metals and metal alloys which have high hydrogen permeability, but which are either too thin to be self supporting, too weak to resist differential pressures across the membrane, or which become embrittled by hydrogen. Support materials are chosen to be lattice matched to the metals and metal alloys. Preferred metals with high permeability for hydrogen include vanadium, niobium, tantalum, zirconium, palladium, and alloys thereof. Hydrogen-permeable membranes include those in which the pores of a porous support matrix are blocked by hydrogen-permeable metals and metal alloys, those in which the pores of a porous metal matrix are blocked with materials which make the membrane impervious to gases other than hydrogen, and cermets fabricated by sintering powders of metals with powders of lattice-matched ceramic.

Mundschau, Michael V.

2005-05-31T23:59:59.000Z

29

Composite oxygen transport membrane  

DOE Patents [OSTI]

A method of producing a composite oxygen ion membrane and a composite oxygen ion membrane in which a porous fuel oxidation layer and a dense separation layer and optionally, a porous surface exchange layer are formed on a porous support from mixtures of (Ln.sub.1-xA.sub.x).sub.wCr.sub.1-yB.sub.yO.sub.3-.delta. and a doped zirconia. In the porous fuel oxidation layer and the optional porous surface exchange layer, A is Calcium and in the dense separation layer A is not Calcium and, preferably is Strontium. Preferred materials are (La.sub.0.8Ca.sub.0.2).sub.0.95Cr.sub.0.5Mn.sub.0.5O.sub.3-.delta. for the porous fuel oxidation and optional porous surface exchange layers and (La.sub.0.8Sr.sub.0.2).sub.0.95Cr.sub.0.5Fe.sub.0.5O.sub.3-.delta. for the dense separation layer. The use of such materials allows the membrane to sintered in air and without the use of pore formers to reduce membrane manufacturing costs. The use of materials, as described herein, for forming the porous layers have application for forming any type of porous structure, such as a catalyst support.

Christie, Gervase Maxwell; Lane, Jonathan A.

2014-08-05T23:59:59.000Z

30

OXYGEN TRANSPORT CERAMIC MEMBRANES  

SciTech Connect (OSTI)

In the present quarter, oxygen transport perovskite ceramic membranes are evaluated for strength and fracture in oxygen gradient conditions. Oxygen gradients are created in tubular membranes by insulating the inner surface from the reducing environment by platinum foils. Fracture in these test conditions is observed to have a gradient in trans and inter-granular fracture as opposed to pure trans-granular fracture observed in homogeneous conditions. Fracture gradients are reasoned to be due to oxygen gradient set up in the membrane, variation in stoichiometry across the thickness and due to varying decomposition of the parent perovskite. The studies are useful in predicting fracture criterion in actual reactor conditions and in understanding the initial evolution of fracture processes.

Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

2002-07-01T23:59:59.000Z

31

OXYGEN TRANSPORT CERAMIC MEMBRANES  

SciTech Connect (OSTI)

In the present quarter, the possibility of using a more complex interfacial engineering approach to the development of reliable and stable oxygen transport perovskite ceramic membranes/metal seals is discussed. Experiments are presented and ceramic/metal interactions are characterized. Crack growth and fracture toughness of the membrane in the reducing conditions are also discussed. Future work regarding this approach is proposed are evaluated for strength and fracture in oxygen gradient conditions. Oxygen gradients are created in tubular membranes by insulating the inner surface from the reducing environment by platinum foils. Fracture in these test conditions is observed to have a gradient in trans and inter-granular fracture as opposed to pure trans-granular fracture observed in homogeneous conditions. Fracture gradients are reasoned to be due to oxygen gradient set up in the membrane, variation in stoichiometry across the thickness and due to varying decomposition of the parent perovskite. The studies are useful in predicting fracture criterion in actual reactor conditions and in understanding the initial evolution of fracture processes.

Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

2003-01-01T23:59:59.000Z

32

OXYGEN TRANSPORT CERAMIC MEMBRANES  

SciTech Connect (OSTI)

In the present quarter, experiments are presented on ceramic/metal interactions of Zirconia/Ni-B-Si system and with a thin Ti coating deposited on zirconia surface. Processing of perovskites of LSC, LSF and LSCF composition for evaluation of mechanical properties as a function of environment are begun. The studies are to be in parallel with LSFCO composition to characterize the segregation of cations and slow crack growth in environmental conditions. La{sub 1-x}Sr{sub x}FeO{sub 3-d} has also been characterized for paramagnetic ordering at room temperature and the evolution of magnetic moments as a function of temperature are investigated. Investigation on the thermodynamic properties of the membrane materials are continued to develop a complete model for the membrane transport.

Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

2003-01-01T23:59:59.000Z

33

OXYGEN TRANSPORT CERAMIC MEMBRANES  

SciTech Connect (OSTI)

Conversion of natural gas to liquid fuels and chemicals is a major goal for the Nation as it enters the 21st Century. Technically robust and economically viable processes are needed to capture the value of the vast reserves of natural gas on Alaska's North Slope, and wean the Nation from dependence on foreign petroleum sources. Technologies that are emerging to fulfill this need are all based syngas as an intermediate. Syngas (a mixture of hydrogen and carbon monoxide) is a fundamental building block from which chemicals and fuels can be derived. Lower cost syngas translates directly into more cost-competitive fuels and chemicals. The currently practiced commercial technology for making syngas is either steam methane reforming (SMR) or a two-step process involving cryogenic oxygen separation followed by natural gas partial oxidation (POX). These high-energy, capital-intensive processes do not always produce syngas at a cost that makes its derivatives competitive with current petroleum-based fuels and chemicals. This project has the following 6 main tasks: Task 1--Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. Task 2--Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability. Task 3--Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres. Task 4--Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures. Task 5--Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability. Task 6--Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques.

Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

2001-12-01T23:59:59.000Z

34

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. Thermogravimetric analysis (TGA) was carried out on La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} to investigate oxygen deficiency ({delta}) of the sample. The TGA was performed in a controlled atmosphere using oxygen, argon, carbon monoxide and carbon dioxide with adjustable gas flow rates. In this experiment, the weight loss and gain of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} was directly measured by TGA. The weight change of the sample was evaluated at between 600 and 1250 C in air or 1000 C as a function of oxygen partial pressure. The oxygen deficiencies calculated from TGA data as a function of oxygen activity and temperature will be estimated and compared with that from neutron diffraction measurement in air. The LSFT and LSFT/CGO membranes were fabricated from the powder obtained from Praxair Specialty Ceramics. The sintered membranes were subjected to microstructure analysis and hardness analysis. The LSFT membrane is composed of fine grains with two kinds of grain morphology. The grain size distribution was characterized using image analysis. In LSFT/CGO membrane a lot of grain pullout was observed from the less dense, porous phase. The hardness of the LSFT and dual phase membranes were studied at various loads. The hardness values obtained from the cross section of the membranes were also compared to that of the values obtained from the surface. An electrochemical cell has been designed and built for measurements of the Seebeck coefficient as a function of temperature and pressure. Measurements on La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} as a function of temperature an oxygen partial pressure are reported. Further analysis of the dilatometry data obtained previously is presented. A series of isotope transients under air separation mode (small gradient) were completed on the membrane of LSCrF-2828 at 900 C. Low pO{sub 2} atmospheres based on with CO-CO{sub 2} mixtures have also been admitted to the delivery side of the LSCrF-2828 membrane to produce the gradients which exist under syngas generation conditions. The CO-CO{sub 2} mixtures have normal isotopic {sup 18}O abundances. The evolution of {sup 18}O on the delivery side in these experiments after an {sup 18}O pulse on the air side reveals a wealth of information about the oxygen transport processes.

S. Bandopadhyay; N. Nagabhushana; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

2005-02-01T23:59:59.000Z

35

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

The present quarterly report describes some of the initial studies on newer compositions and also includes newer approaches to address various materials issues such as in metal-ceramic sealing. The current quarter's research has also focused on developing a comprehensive reliability model for predicting the structural behavior of the membranes in realistic conditions. In parallel to industry provided compositions, models membranes have been evaluated in varying environment. Of importance is the behavior of flaws and generation of new flaws aiding in fracture. Fracture mechanics parameters such as crack tip stresses are generated to characterize the influence of environment. Room temperature slow crack growth studies have also been initiated in industry provided compositions. The electrical conductivity and defect chemistry of an A site deficient compound (La{sub 0.55}Sr{sub 0.35}FeO{sub 3}) was studied. A higher conductivity was observed for La{sub 0.55}Sr{sub 0.35}FeO{sub 3} than that of La{sub 0.60}Sr{sub 0.40}FeO{sub 3} and La{sub 0.80}Sr{sub 0.20}FeO{sub 3}. Defect chemistry analysis showed that it was primarily contributed by a higher carrier concentration in La{sub 0.55}Sr{sub 0.35}FeO{sub 3}. Moreover, the ability for oxygen vacancy generation is much higher in La{sub 0.55}Sr{sub 0.35}FeO{sub 3} as well, which indicates a lower bonding strength between Fe-O and a possible higher catalytic activity for La{sub 0.55}Sr{sub 0.35}FeO{sub 3}. The program continued to investigate the thermodynamic properties (stability and phase separation behavior) and total conductivity of prototype membrane materials. The data are needed together with the kinetic information to develop a complete model for the membrane transport. Previous report listed initial measurements on a sample of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-x} prepared in-house by Praxair. Subsequently, a second sample of powder from a larger batch of sample were characterized and compared with the results from the previous batch.

S. Bandopadhyay; N. Nagabhushana; Thomas W. Eagar; Harold R. Larson; Raymundo Arroyave; X.-D Zhou; Y.-W. Shin; H.U. Anderson; Nigel Browning; Alan Jacobson; C.A. Mims

2003-11-01T23:59:59.000Z

36

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In this report, in situ neutron diffraction was used to characterize the chemical and structural properties of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} (here after as L2SF55T) specimen, which was subject to measurements of neutron diffraction from room temperature to 900 C. It was found that space group of R3c yielded a better refinement than a cubic structure of Pm3m. Oxygen occupancy was nearly 3 in the region from room temperature to 700 C, above which the occupancy decreased due to oxygen loss. Dense OTM bars provided by Praxair were loaded to fracture at varying stress rates. Studies were done at room temperature in air and at 1000 C in a specified environment to evaluate slow crack growth behavior. The X-Ray data and fracture mechanisms points to non-equilibrium decomposition of the LSFCO OTM membrane. The non-equilibrium conditions could probably be due to the nature of the applied stress field (stressing rates) and leads to transition in crystal structures and increased kinetics of decomposition. The formations of a Brownmillerite or Sr2Fe2O5 type structures, which are orthorhombic are attributed to the ordering of oxygen vacancies. The cubic to orthorhombic transitions leads to 2.6% increase in strains and thus residual stresses generated could influence the fracture behavior of the OTM membrane. Continued investigations on the thermodynamic properties (stability and phase-separation behavior) and total conductivity of prototype membrane materials were carried out. The data are needed together with the kinetic information to develop a complete model for the membrane transport. Previously characterization, stoichiometry and conductivity measurements for samples of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} were reported. In this report, measurements of the chemical and thermal expansion as a function of temperature and p{sub O2} are described.

S. Bandopadhyay; N. Nagabhushana; X.-D Zhou; Q. Cai; J. Yang; W.B. Yelon; W.J. James; H.U. Anderson; Alan Jacobson; C.A. Mims

2004-05-01T23:59:59.000Z

37

Catalyst containing oxygen transport membrane  

SciTech Connect (OSTI)

A composite oxygen transport membrane having a dense layer, a porous support layer and an intermediate porous layer located between the dense layer and the porous support layer. Both the dense layer and the intermediate porous layer are formed from an ionic conductive material to conduct oxygen ions and an electrically conductive material to conduct electrons. The porous support layer has a high permeability, high porosity, and a high average pore diameter and the intermediate porous layer has a lower permeability and lower pore diameter than the porous support layer. Catalyst particles selected to promote oxidation of a combustible substance are located in the intermediate porous layer and in the porous support adjacent to the intermediate porous layer. The catalyst particles can be formed by wicking a solution of catalyst precursors through the porous support toward the intermediate porous layer.

Christie, Gervase Maxwell; Wilson, Jamie Robyn; van Hassel, Bart Antonie

2012-12-04T23:59:59.000Z

38

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

In the present quarter, experiments are presented on ceramic/metal interactions of Zirconia/ Ni-B-Si system and with a thin Ti coating deposited on zirconia surface. Existing facilities were modified for evaluation of environmental assisted slow crack growth and creep in flexural mode. Processing of perovskites of LSC, LSF and LSCF composition were continued for evaluation of mechanical properties as a function of environment. These studies in parallel to those on the LSFCO composition is expect to yield important information on questions such as the role of cation segregation and the stability of the perovskite structure on crack initiation vs. crack growth. Studies have been continued on the La{sub 1-x}Sr{sub x}FeO{sub 3-d} composition using neutron diffraction and TGA studies. A transition from p-type to n-type of conductor was observed at relative low pO{sub 2}, at which the majority carriers changed from the holes to electrons because of the valence state decreases in Fe due to the further loss of oxygen. Investigation on the thermodynamic properties of the membrane materials are continued to develop a complete model for the membrane transport. Data obtained at 850 C show that the stoichiometry in La{sub 0.2}Sr{sub 0.8}Fe{sub 0.8}Cr{sub 0.2}O{sub 3-x} vary from {approx}2.85 to 2.6 over the pressure range studied. From the stoichiometry a lower limit of 2.6 corresponding to the reduction of all Fe{sup 4+} to Fe{sup 3+} and no reduction of Cr{sup 3+} is expected.

S. Bandopadhyay; N. Nagabhushana

2003-08-07T23:59:59.000Z

39

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped Ti-substituted perovskites, La{sub 0.7}Sr{sub 0.3}Mn{sub 1-x}Ti{sub x}O{sub 3}, with 0 {le} x {le} 0.20, were investigated by neutron diffraction, magnetization, electric resistivity, and magnetoresistance (MR) measurements. All samples show a rhombohedral structure (space group R3C) from 10 K to room temperature. At room temperature, the cell parameters a, c and the unit cell volume increase with increasing Ti content. However, at 10 K, the cell parameter a has a maximum value for x = 0.10, and decreases for x > 0.10, while the unit cell volume remains nearly constant for x > 0.10. The average (Mn,Ti)-O bond length increases up to x = 0.15, and the (Mn,Ti)-O-(Mn,Ti) bond angle decreases with increasing Ti content to its minimum value at x = 0.15 at room temperature. Below the Curie temperature TC, the resistance exhibits metallic behavior for the x {le} 0.05 samples. A metal (semiconductor) to insulator transition is observed for the x {ge} 0.10 samples. A peak in resistivity appears below TC for all samples, and shifts to a lower temperature as x increases. The substitution of Mn by Ti decreases the 2p-3d hybridization between O and Mn ions, reduces the bandwidth W, and increases the electron-phonon coupling. Therefore, the TC shifts to a lower temperature and the resistivity increases with increasing Ti content. A field-induced shift of the resistivity maximum occurs at x {le} 0.10 compounds. The maximum MR effect is about 70% for La{sub 0.7}Sr{sub 0.3}Mn{sub 0.8}Ti{sub 0.2}O{sub 3}. The separation of TC and the resistivity maximum temperature T{sub {rho},max} enhances the MR effect in these compounds due to the weak coupling between the magnetic ordering and the resistivity as compared with La{sub 0.7}Sr{sub 0.3}MnO{sub 3}. The bulk densities of the membranes were determined using the Archimedes method. The bulk density was 5.029 and 5.57 g/cc for LSFT and dual phase membranes, respectively. The microstructure of the dual phase membrane was analyzed using SEM. It is evident from the micrograph that the microstructure is composed of dual phases. The dense circular regions are enclosed by the less dense, continuous phase which accommodates most of the pores. The pores are normally aggregated and found clustered along the dense regions where as the dense regions do not have pores. Upon closer observation of the micrograph it is revealed that the dense region has a clear circular cleavage or crack as their boundary. The circular cleavage clearly encompasses a dense region and which consists of no pore or any flaw that is visible. The size distribution of the dense, discontinuous regions is varying from 5 to 20 {micro}m with a D{sub 50} of 15 {micro}m. The grain size distribution was estimated from the micrographs using image analysis and a unimodal distribution of grains was observed with an average grain size of 1.99 {micro}m. The chemical compositions of the membranes were analyzed using EDS analysis and no other impurities were observed. The XRD analysis was carried out for the membranes and the phase purity was confirmed. The fracture toughness of LSFT membranes at room temperature has to be calculated using the Vickers indentation method. An electrochemical cell has been designed and built for measurements of the ionic conductivity by the use of blocking electrodes. Preliminary measurements on La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} are reported. Modifications to the apparatus to improve the data quality have been completed. Electron microscopy studies of the origin of the slow kinetics on reduction of ferrites have been initiated. A series of isotope transients under air separation mode (small gradient) were completed on the membrane of LSCrF-2828 at 900 C. Low pO{sub 2} atmospheres based on with CO-CO{sub 2} mixtures have also been admitted to the delivery side of the LSCrF-2828 membrane to produce the gradient

S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

2005-05-01T23:59:59.000Z

40

Active membrane having uniform physico-chemically functionalized ion channels  

DOE Patents [OSTI]

The present invention relates to a physicochemically-active porous membrane for electrochemical cells that purports dual functions: an electronic insulator (separator) and a unidirectional ion-transporter (electrolyte). The electrochemical cell membrane is activated for the transport of ions by contiguous ion coordination sites on the interior two-dimensional surfaces of the trans-membrane unidirectional pores. One dimension of the pore surface has a macroscopic length (1 nm-1000 .mu.m) and is directed parallel to the direction of an electric field, which is produced between the cathode and the anode electrodes of an electrochemical cell. The membrane material is designed to have physicochemical interaction with ions. Control of the extent of the interactions between the ions and the interior pore walls of the membrane and other materials, chemicals, or structures contained within the pores provides adjustability of the ionic conductivity of the membrane.

Gerald, II, Rex E; Ruscic, Katarina J; Sears, Devin N; Smith, Luis J; Klingler, Robert J; Rathke, Jerome W

2012-09-24T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Oxygen Transport Membranes  

SciTech Connect (OSTI)

The focus of this research was to develop new membrane materials by synthesizing different compounds and determining their defect structures, crystallographic structures and electrical properties. In addition to measuring electrical conductivity, oxygen vacancy concentration was also evaluated using thermogravimetry, Neutron diffraction and Moessbauer Spectroscopy. The reducing conditions (CO{sub 2}/CO/H{sub 2} gas mixtures with steam) as encountered in a reactor environment can be expected to have significant influence on the mechanical properties of the oxides membranes. Various La based materials with and without Ti were selected as candidate membrane materials for OTM. The maximum electrical conductivity of LSF in air as a function of temperature was achieved at < 600 C and depends on the concentration of Sr (acceptor dopant). Oxygen occupancy in LSF was estimated using Neutron diffractometry and Moessbauer Spectroscopy by measuring magnetic moment changes depending on the Fe{sup 3+} and Fe{sup 4+} ratio. After extensive studies of candidate materials, lanthanum ferrites (LSF and LSFT) were selected as the favored materials for the oxygen transport membrane (OTM). LSF is a very good material for an OTM because of its high electronic and oxygen ionic conductivity if long term stability and mechanical strength are improved. LSFT not only exhibits p-type behavior in the high oxygen activity regime, but also has n-type conduction in reducing atmospheres. Higher concentrations of oxygen vacancies in the low oxygen activity regime may improve the performance of LSFT as an OTM. The hole concentration is related to the difference in the acceptor and donor concentration by the relation p = [Sr'{sub La}]-[Ti{sm_bullet}{sub Fe}]. The chemical formulation predicts that the hole concentration is, p = 0.8-0.45 or 0.35. Experimental measurements indicated that p is about {approx} 0.35. The activation energy of conduction is 0.2 eV which implies that LSCF conducts via the small polaron conduction mechanism. Scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS) were used to develop strategies to detect and characterize vacancy creation, dopant segregations and defect association in the oxygen conducting membrane material. The pO{sub 2} and temperature dependence of the conductivity, non-stoichiometry and thermal-expansion behavior of compositions with increasing complexity of substitution on the perovskite A and B sites were studied. Studies with the perovskite structure show anomalous behavior at low oxygen partial pressures (<10{sup -5} atm). The anomalies are due to non-equilibrium effects and can be avoided by using very strict criteria for the attainment of equilibrium. The slowness of the oxygen equilibration kinetics arises from two different mechanisms. In the first, a two phase region occurs between an oxygen vacancy ordered phase such as brownmillerite SrFeO{sub 2.5} and perovskite SrFeO{sub 3-x}. The slow kinetics is associated with crossing the two phase region. The width of the miscibility gap decreases with increasing temperature and consequently the effect is less pronounced at higher temperature. The preferred kinetic pathway to reduction of perovskite ferrites when the vacancy concentration corresponds to the formation of significant concentrations of Fe{sup 2+} is via the formation of a Ruddlesden-Popper (RP) phases as clearly observed in the case of La{sub 0.5}Sr{sub 0.5}FeO{sub 3-x} where LaSrFeO{sub 4} is found together with Fe. In more complex compositions, such as LSFTO, iron or iron rich phases are observed locally with no evidence for the presence of discrete RP phase. Fracture strength of tubular perovskite membranes was determined in air and in reducing atmospheric conditions. The strength of the membrane decreased with temperature and severity of reducing conditions although the strength distribution (Weibull parameter, m) was relatively unaltered. Surface and volume dominated the fracture origins and the overall fracture was purely transgranular. The dual phas

S. Bandopadhyay

2008-08-30T23:59:59.000Z

42

Nanoengineered membranes for controlled transport  

DOE Patents [OSTI]

A nanoengineered membrane for controlling material transport (e.g., molecular transport) is disclosed. The membrane includes a substrate, a cover definining a material transport channel between the substrate and the cover, and a plurality of fibers positioned in the channel and connected to an extending away from a surface of the substrate. The fibers are aligned perpendicular to the surface of the substrate, and have a width of 100 nanometers or less. The diffusion limits for material transport are controlled by the separation of the fibers. In one embodiment, chemical derivitization of carbon fibers may be undertaken to further affect the diffusion limits or affect selective permeability or facilitated transport. For example, a coating can be applied to at least a portion of the fibers. In another embodiment, individually addressable carbon nanofibers can be integrated with the membrane to provide an electrical driving force for material transport.

Doktycz, Mitchel J. (Oak Ridge, TN) [Oak Ridge, TN; Simpson, Michael L. (Knoxville, TN) [Knoxville, TN; McKnight, Timothy E. (Greenback, TN) [Greenback, TN; Melechko, Anatoli V. (Oak Ridge, TN) [Oak Ridge, TN; Lowndes, Douglas H. (Knoxville, TN) [Knoxville, TN; Guillorn, Michael A. (Knoxville, TN) [Knoxville, TN; Merkulov, Vladimir I. (Oak Ridge, TN) [Oak Ridge, TN

2010-01-05T23:59:59.000Z

43

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In this report, Moessbauer spectroscopy was used to study the local environmentals of LSFT with various level of oxygen deficiency. Ionic valence state, magnetic interaction and influence of Ti on superexchange are discussed Stable crack growth studies on Dense OTM bars provided by Praxair were done at elevated temperature, pressure and elevated conditions. Post-fracture X-ray data of the OTM fractured at 1000 C in environment were refined by FullProf code and results indicate a distortion of the parent cubic perovskite to orthorhombic structure with reduced symmetry. TGA-DTA studies on the post-fracture samples also indicated residual effect arising from the thermal and stress history of the samples. An electrochemical cell has been designed and built for measurements of the Seebeck coefficient as a function of temperature and pressure. The initial measurements on La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} are reported. Neutron diffraction measurements of the same composition are in agreement with both the stoichiometry and the kinetic behavior observed in coulometric titration measurements. A series of isotope transients under air separation mode (small gradient) were completed on the membrane of LSCrF-2828 at 900 C. Low pO{sub 2} atmospheres based on with CO-CO{sub 2} mixtures have also been admitted to the delivery side of the LSCrF-2828 membrane to produce the gradients which exist under syngas generation conditions. The COCO{sub 2} mixtures have normal isotopic {sup 18}O abundances. The evolution of {sup 18}O on the delivery side in these experiments after an {sup 18}O pulse on the air side reveals a wealth of information about the oxygen transport processes.

S. Bandopadhyay; N. Nagabhushana; X.-D Zhou; Q. Cai; J. Yang; W.B. Yelon; W.J. James; H.U. Anderson; Alan Jacobson; C.A. Mims

2004-10-01T23:59:59.000Z

44

Salinity tolerance in plants: attempts to manipulate ion transport  

E-Print Network [OSTI]

Ion transport is the major determining factor of salinity tolerance in plants. A simple scheme of a plant cell with ion fluxes provides basic understanding of ion transport and the corresponding changes of ion concentrations under salinity. The review describes in detail basic principles of ion transport for a plant cell, introduces set of transporters essential for sodium and potassium uptake and efflux, analyses driving forces of ion transport and compares ion fluxes measured by several techniques. Study of differences in ion transport between salt tolerant halophytes and salt-sensitive plants with an emphasis on transport of potassium and sodium via plasma membranes offers knowledge for increasing salinity tolerance. Effects of salt stress on ion transport properties of membranes show huge opportunities for manipulating ion transport. Several attempts to overexpress or knockout ion transporters for changing salinity tolerance are described. Future perspectives are questioned with more attention given to potential candidate ion channels and transporters for altered expression. The potential direction of increasing salinity tolerance by modifying ion channels and transporters is discussed and questioned. An alternative approach from synthetic biology is to modify the existing membrane transport proteins or create new ones with desired properties for transforming agricultural crops. The approach had not been widely used earlier and leads also to theoretical and pure scientific aspects of protein chemistry, structure-function relations of membrane proteins, systems biology and physiology of stress and ion homeostasis.

Vadim Volkov

2014-11-06T23:59:59.000Z

45

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In this report, in situ neutron diffraction was used to characterize the chemical and structural properties of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} (here after as L2SF55T) specimen, which was subject to measurements of neutron diffraction from room temperature to 900 C in N{sub 2}. Space group of R3c was found to result in a better refinement and is used in this study. The difference for crystal structure, lattice parameters and local crystal chemistry for LSFT nearly unchanged when gas environment switched from air to N{sub 2}. Stable crack growth studies on Dense OTM bars provided by Praxair were done at room temperature in air. A bridge-compression fixture was fabricated to achieve stable pre-cracks from Vickers indents. Post fracture evaluation indicated stable crack growth from the indent and a regime of fast fracture. Post-fracture X-ray data of the OTM fractured at 1000 C in environment were refined by FullProf code and results indicate a distortion of the parent cubic perovskite to orthorhombic structure with reduced symmetry. TGA-DTA studies on the post-fracture samples also indicated residual effect arising from the thermal and stress history of the samples. The thermal and chemical expansion of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} were studied at 800 {le} T {le} 1000 C and at {approx} 1 x 10{sup -15} {le} pO{sub 2} {le} 0.21 atm. The thermal expansion coefficient of the sample was calculated from the dilatometric analysis in the temperature range between room temperature and 1200 C in air. A series of isotope transients under air separation mode (small gradient) were completed on the membrane of LSCrF-2828 at 900 C. Low pO{sub 2} atmospheres based on with CO-CO{sub 2} mixtures have also been admitted to the delivery side of the LSCrF-2828 membrane to produce the gradients which exist under syngas generation conditions. The CO-CO{sub 2} mixtures have normal isotopic {sup 18}O abundances. The evolution of {sup 18}O on the delivery side in these experiments after an {sup 18}O pulse on the air side reveals a wealth of information about the oxygen transport processes.

S. Bandopadhyay; N. Nagabhushana; X.-D Zhou; Q. Cai; J. Yang; W.B. Yelon; W.J. James; H.U. Anderson; Alan Jacobson; C.A. Mims

2004-05-01T23:59:59.000Z

46

Transport study of hafnium(IV) and zirconium(IV) ions mutual separation by using Tri-n-butyl phosphate-xylene-based supported liquid membranes  

SciTech Connect (OSTI)

A Hf transport study through supported liquid membranes has been carried out to determine flux and permeability data for this metal ion. Tri-n-butyl phosphate (TBP)-xylene-based liquid membranes supported in polypropylene hydrophobic microporous film have been used. These data for hafnium and the previous data for zirconium have furnished the Zr to Hf flux ratio (S) as a function of nitric acid and TBP concentrations of the order of 12 in a single stage at room temperature. Optimum conditions for the separation of these two metal ions appear to 5-6 TBP mol/dm{sup 3} HNO{sub 3}, concentrations {le} 2.93 mol/dm{sup 3}, and 10C. The value of S from an aqueous solution containing 2.4% Hf with respect to Zr has been found to be >125 at 10C and 1.78 mol/dm{sup 3} TBP concentration in the membrane. The technique appears to be feasible for purification of Zr respect to Hf or vice versa.

Chaudry, M.A.; Ahmed, B. (Pakistan Inst. of Nuclear Science and Technology, Islamabad (Pakistan))

1992-02-01T23:59:59.000Z

47

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In the current research, the electrical conductivity and Seebeck coefficient were measured as a function of temperature in air. Based on these measurements, the charge carrier concentration, net acceptor dopant concentration, activation energy of conduction and mobility were estimated. The studies on the fracture toughness of the LSFT and dual phase membranes at room temperature have been completed and reported previously. The membranes that are exposed to high temperatures at an inert and a reactive atmosphere undergo many structural and chemical changes which affects the mechanical properties. To study the effect of temperature on the membranes when exposed to an inert environment, the membranes (LAFT and Dual phase) were heat treated at 1000 C in air and N{sub 2} atmosphere and hardness and fracture toughness of the membranes were studied after the treatment. The indentation method was used to find the fracture toughness and the effect of the heat treatment on the mechanical properties of the membranes. Further results on the investigation of the origin of the slow kinetics on reduction of ferrites have been obtained. The slow kinetics appears to be related to a non-equilibrium reduction pathway that initially results in the formation of iron particles. At long times, equilibrium can be reestablished with recovery of the perovskite phase. 2-D modeling of oxygen movement has been undertaken in order to fit isotope data. The model will serve to study ''frozen'' profiles in patterned or composite membranes.

S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

2005-11-01T23:59:59.000Z

48

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

In this quarter a systematic analysis on the decomposition behavior of the OTM membranes at air and nitrogen were initiated to understand the structural and stoichiometric changes associated with elevated temperatures. Evaluation of the flexural strengths using 4-point bend test was also started for the dual phase membranes. Initial results on the synthesis of dual phase composite materials have been obtained. The measurements have focused on the compatibility of mixed conductors with the pure ionic conductors yttria stabilized zirconia (YSZ) and gadolinium doped ceria (GDC). The initial results obtained for three different mixed conductors suggest that (GDC) is the better choice. A new membrane permeation system has been designed and tested and sintering studies of biphasic systems are in progress.

S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

2006-05-01T23:59:59.000Z

49

OXYGEN TRANSPORT CERAMIC MEMBRANES  

SciTech Connect (OSTI)

This is the fifth quarterly report on a new study to develop a ceramic membrane/metal joint. Results of wetting experiments on commercially available Nickel based brazing alloys on perovskite surfaces are described. Additionally, experimental and numerical investigations on the strength of concentric ceramic/metal joints are presented.

Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

2001-02-01T23:59:59.000Z

50

OXYGEN TRANSPORT CERAMIC MEMBRANES  

SciTech Connect (OSTI)

This is the fourth quarterly report on a new study to develop a ceramic membrane/metal joint. The first experiments using the La-Sr-Fe-O ceramic are reported. Some of the analysis performed on the samples obtained are commented upon. A set of experiments to characterize the mechanical strength and thermal fatigue properties of the joints has been designed and begun. Finite element models of joints used to model residual stresses are described.

Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

2000-07-01T23:59:59.000Z

51

Interpenetrating polymer network ion exchange membranes and method for preparing same  

DOE Patents [OSTI]

Interpenetrating polymer network ion exchange membranes include a microporous polymeric support film interpenetrated by an ion exchange polymer and are produced by absorbing and polymerizing monomers within the support film. The ion exchange polymer provides ion exchange ligands at the surface of and throughout the support film which have sufficient ligand mobility to extract and transport ions across the membrane.

Alexandratos, Spiro D. (Knoxville, TN); Danesi, Pier R. (Vienna, AT); Horwitz, E. Philip (Naperville, IL)

1989-01-01T23:59:59.000Z

52

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In the previous research, the reference point of oxygen occupancy was determined and verified. In the current research, the oxygen occupancy was investigated at 1200 C as a function of oxygen activity and compared with that at 1000 C. The cause of bumps at about 200 C was also investigated by using different heating and cooling rates during TGA. The fracture toughness of LSFT and dual phase membranes at room temperature is an important mechanical property. Vicker's indentation method was used to evaluate this toughness. Through this technique, a K{sub Ic} (Mode-I Fracture Toughness) value is attained by means of semi-empirical correlations between the indentation load and the length of the cracks emanating from the corresponding Vickers indentation impression. In the present investigation, crack propagation behavior was extensively analyzed in order to understand the strengthening mechanisms involved in the non-transforming La based ceramic composites. Cracks were generated using Vicker's indenter and used to identify and evaluate the toughening mechanisms involved. Preliminary results of an electron microscopy study of the origin of the slow kinetics on reduction of ferrites have been obtained. The slow kinetics appear to be related to a non-equilibrium reduction pathway that initially results in the formation of iron particles. At long times, equilibrium can be reestablished with recovery of the perovskite phase. Modeling of the isotopic transients on operating membranes (LSCrF-2828 at 900 C) and a ''frozen'' isotope profile have been analyzed in conjunction with a 1-D model to reveal the gradient in oxygen diffusivity through the membrane under conditions of high chemical gradients.

S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

2005-08-01T23:59:59.000Z

53

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. The in situ electrical conductivity and Seebeck coefficient measurements were made on LSFT at 1000 and 1200 C over the oxygen activity range from air to 10{sup -15} atm. The electrical conductivity measurements exhibited a p to n type transition at an oxygen activity of 1 x 10{sup -10} at 1000 C and 1 x 10{sup -6} at 1200 C. Thermogravimetric studies were also carried out over the same oxygen activities and temperatures. Based on the results of these measurements, the chemical and mechanical stability range of LSFT were determined and defect structure was established. The studies on the fracture toughness of the LSFT and dual phase membranes exposed to air and N{sub 2} at 1000 C was done and the XRD and SEM analysis of the specimens were carried out to understand the structural and microstructural changes. The membranes that are exposed to high temperatures at an inert and a reactive atmosphere undergo many structural and chemical changes which affect the mechanical properties. A complete transformation of fracture behavior was observed in the N{sub 2} treated LSFT samples. Further results to investigate the origin of the slow kinetics on reduction of ferrites have been obtained. The slow kinetics appear to be related to a non-equilibrium reduction pathway that initially results in the formation of iron particles. At long times, equilibrium can be reestablished with recovery of the perovskite phase. Recent results on transient kinetic data are presented. The 2-D modeling of oxygen movement has been undertaken in order to fit isotope data. The model is used to study ''frozen'' profiles in patterned or composite membranes.

S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

2005-02-01T23:59:59.000Z

54

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

Ti doping on La{sub 1-x}Sr{sub x}FeO{sub 3-{delta}} (LSF) tends to increase the oxygen equilibration kinetics of LSF in lower oxygen activity environment because of the high valence state of Ti. However, the addition of Ti decreases the total conductivity because the acceptor ([Sr{prime}{sub La}]) is compensated by the donor ([Ti{sub Fe}{sup {sm_bullet}}]) which decreases the carrier concentration. The properties of La{sub 0.2}Sr{sub 0.8}Fe{sub 1-x}Ti{sub x}O{sub 3-{delta}} (LSFT, x = 0.45) have been experimentally and theoretically investigated to elucidate (1) the dependence of oxygen occupancy and electrochemical properties on temperature and oxygen activity by thermogravimetric analysis (TGA) and (2) the electrical conductivity and carrier concentration by Seebeck coefficient and electrical measurements. In the present study, dual phase (La{sub 0.2}Sr{sub 0.8}Fe{sub 0.6}Ti{sub 0.4}O{sub 3-{delta}}/Ce{sub 0.9}Gd{sub 0.1}O{sub 2-{delta}}) membranes have been evaluated for structural properties such as hardness, fracture toughness and flexural strength. The effect of high temperature and slightly reducing atmosphere on the structural properties of the membranes was studied. The flexural strength of the membrane decreases upon exposure to slightly reducing conditions at 1000 C. The as-received and post-fractured membranes were characterized using XRD, SEM and TG-DTA to understand the fracture mechanisms. Changes in structural properties of the composite were sought to be correlated with the physiochemical features of the two-phases. We have reviewed the electrical conductivity data and stoichiometry data for La{sub 0.2}Sr{sub 0.8}Cr{sub 0.2}Fe{sub 0.8}O{sub 3-{delta}} some of which was reported previously. Electrical conductivity data for La{sub 0.2}Sr{sub 0.8}Cr{sub 0.2}Fe{sub 0.8}O{sub 3-{delta}} (LSCrF) were obtained in the temperature range, 752 {approx} 1055 C and in the pO{sub 2} range, 10{sup -18} {approx} 0.5 atm. The slope of the plot of log {sigma} vs. log pO{sub 2} is {approx} 1/5 in the p-type region, pO{sub 2} = 10{sup -5} {approx} 10{sup -1} atm. The pO{sub 2} at which the p-n transition is observed increases with increasing temperature. The activation energy for ionic conduction was estimated to be 0.86 eV from an Arrhenius plot of the minimum conductivity vs. reciprocal temperature. At temperatures below 940 C, a plateau in the conductivity isotherm suggests the presence of a two-phase region. Most likely, phase separation occurs to form a mixture of a perovskite phase and an oxygen vacancy ordered phase related to brownmillerite. Additional data for the oxygen non stoichiometry are presented.

S. Bandopadhyay; T. Nithyanantham

2006-12-31T23:59:59.000Z

55

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

A non-agglomerated and nanocrystalline-sized powder was successfully produced using ethylene glycol nitrate methods. The LSFT powder prepared using this method exhibits well dispersed and nano-sized particles about 100-200 nm. The density of LSFT sintered at 1300 C was about 90% of the theoretical density at which is 100 C less than that of the previous LSFT which was sintered at 1400 C. The sample sintered at 1400 C exhibited the evidence of a liquid phase at the grain boundaries and 2nd phase formation which probably caused low mechanical stability. The electrical conductivity and Seebeck coefficient were measured as a function of temperature. The LSFT-CGO specimens were cut from the as sintered bars and used for the evaluation of Mechanical Properties after polishing. The effect of strain rate on the flexural strength of the LSFT-CGO test specimens was studied. Three strain rates 6, 60 and 600 {micro}m/ min were chosen for this study. It is observed from the results that with increasing cross head speed the membrane takes higher loads to fail. A reduction in the strength of the membrane was observed at 1000 C in N{sub 2}. Two different routes were investigated to synthesis GDC using either formate or carbonate precursors. The precursor and CGO particle morphologies were examined by scanning electron microscopy. The thermal decomposition behaviors of Ce(Gd)(HCOO){sub 3} and Ce(Gd)(CO{sub 3})(OH) were determined by thermogravimetric analysis (TGA) at a rate of 3 C/min in air. The X-ray powder diffraction patterns of the precursor and CGO were collected and nitrogen adsorption isotherms were measured. Conductivity measurements were made by AC impedance spectroscopy on sintered disks in air using platinum electrodes.

S. Bandopadhyay; T. Nithyanantham

2006-06-30T23:59:59.000Z

56

Studies on the in situ electrooxidation and selective permeation of cerium(IV) across a bulk liquid membrane containing tributyl phosphate as the ion transporter  

SciTech Connect (OSTI)

The results of experiments carried out to develop a liquid membrane (LM) technique for the extractive permeation of cerium from nitric acid solutions are described. In-situ electrooxidation of Ce{sup 3+} to extractable Ce{sup 4+} and its transport across bulk LM (BLM) composed of tri-n-butyl phosphate (TBP)/dodecane mixtures was systematically studied under varied hydrodynamical and chemical conditions. The permeability of metal ions across the BLM was dependent on the efficiency of extraction, ionic activity of feed solutions, stirring rate, composition of the receiving phase, etc. The transport rates were found to vary linearly (a log-log correlation) with the cation concentration in feed solutions and concentration of TBP in BLM. A permeation velocity equation for cerium ion through the membrane has been proposed. More than 90% permeation of Ce with a maximum flux of 8.63 x 10{sup {minus}5} mol/m{sup 2}/s could be accomplished under the experimental conditions: stirring rates at feed and strip solutions were 380 and 300 rpm, respectively; feed was 1 mol/dm{sup 3} of HNO{sub 3} containing 0.005 mol/dm{sup 3} Ce(NO{sub 3}){sub 3}; LM contained 30% TBP/dodecane; and the receiving phase was distilled water. Radiochemically pure Ce-144 was partitioned from the Ce-Am mixture obtained by extraction chromatographic fractioning of high level radioactive waste. This also resulted in the purification of Am-241 in the feed solution with a decontamination factor of {approximately} 12 from Ce.

Kedari, C.S.; Pandit, S.S.; Ramanujam, A. [Bhabha Atomic Research Centre, Trombay (India). Fuel Reprocessing Div.] [Bhabha Atomic Research Centre, Trombay (India). Fuel Reprocessing Div.

1999-06-01T23:59:59.000Z

57

Electric Field Modulation of the Membrane Potential in Solid-State Ion Channels  

E-Print Network [OSTI]

channel. KEYWORDS: Nanochannel, membrane potential, electrofluidic gating, ion transport, salinityElectric Field Modulation of the Membrane Potential in Solid-State Ion Channels Weihua Guan a rapid flow of ions across the cell membrane. Normal physiological functions, such as generating action

Reed, Mark

58

Oxygen Transport Ceramic Membranes  

SciTech Connect (OSTI)

The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and initial studies on newer composition of Ti doped LSF. Dense OTM bars provided by Praxair were loaded to fracture at varying stress rates. Studies were done at room temperature in air and at 1000 C in a specified environment to evaluate slow crack growth behavior. In addition, studies were also begun to obtain reliable estimates of fracture toughness and stable crack growth in specific environments. Newer composition of Ti doped LSF membranes were characterized by neutron diffraction analysis. Quench studies indicated an apparent correlation between the unit cell volume and oxygen occupancy. The studies however, indicated an anomaly of increasing Fe/Ti ratio with change in heat treatment. Ti doped LSF was also characterized for stoichiometry as a function of temp and pO{sub 2}. The non stoichiometry parameter {delta} was observed to increase almost linearly on lowering pO{sub 2} until a ideal stoichiometric composition of {delta} = 0.175 was approached.

S. Bandopadhyay; N. Nagabhushana; X.-D Zhou; W.B. Yelon; H.U. Anderson; Alan Jacobson; C.A. Mims

2004-02-01T23:59:59.000Z

59

Transport of Alkali Halides through a Liquid Organic Membrane Containing a Ditopic Salt-Binding Receptor  

E-Print Network [OSTI]

in the solid state as contact ion pairs. Transport experiments, using a supported liquid membrane and high saltTransport of Alkali Halides through a Liquid Organic Membrane Containing a Ditopic Salt and anion receptors. All transport systems exhibit the same qualitative order of ion selectivity; that is

Smith, Bradley D.

60

Charge Inversion, Water Splitting, and Vortex Suppression Due to DNA Sorption on Ion-Selective Membranes and Their Ion-Current  

E-Print Network [OSTI]

These membranes show a unique property of selective ion transport through the nanopores of IEMs embedded to saturate at a limiting current beyond a critical cross-membrane voltage drop as a result of the ion-transport-Selective Membranes and Their Ion-Current Signatures Zdenek Slouka, Satyajyoti Senapati, Yu Yan, and Hsueh-Chia Chang

Chang, Hsueh-Chia

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

An increasing number of synthetic compounds have been shown to facilitate ion and polar molecule transport across  

E-Print Network [OSTI]

transport of ions and polar molecules across biological membranes is essential for normal cell function synthetic transporters shown to be active in both model bilayers and cellular membranes. Mechanism of ion simulations of unassisted Na+ and Cl­ ion transport across a bilayer membrane. As the ion enters the outer

Smith, Bradley D.

62

Nanostructured Silicon Membranes for Control of Molecular Transport  

SciTech Connect (OSTI)

A membrane that allows selective transport of molecular species requires precise engineering on the nanoscale. Membrane permeability can be tuned by controlling the physical structure of the pores. Here, a combination of electron-beam and optical lithography, along with cryogenic deep reactive ion etching, has been used to fabricate silicon membranes that are physically robust, have uniform pore-sizes, and are directly integrated into a microfluidic network. Additional reductions in pore size were achieved using plasma enhanced chemical vapor deposition of silicon dioxide to coat membrane surfaces. Cross sectioning of the membranes using focused ion beam milling was used to determine the physical shape of the membrane pores before and after coating.

Srijanto, Bernadeta R [ORNL] [ORNL; Retterer, Scott T [ORNL] [ORNL; Fowlkes, Jason Davidson [ORNL] [ORNL; Doktycz, Mitchel John [ORNL] [ORNL

2010-01-01T23:59:59.000Z

63

Charge Transport through a Novel Zeolite Y Membrane by a Self-Exchange Process Hyunjung Lee and Prabir K. Dutta*  

E-Print Network [OSTI]

Charge Transport through a Novel Zeolite Y Membrane by a Self-Exchange Process Hyunjung Lee-photoresist-coated membranes were found. Accessibility of the intrazeolitic volume was examined by ion exchange and for optimally illuminated membranes was comparable to uncoated membranes. Charge transport through the membrane

Dutta, Prabir K.

64

Theoretical and experimental analysis of conductivity, ion diffusion and molecular transport during cell electroporation --Relation between short-lived and  

E-Print Network [OSTI]

electric field, which enables transport of molecules and ions across the cell membrane. Several and ions due to the hydrophobic nature of the lipid bilayer. Transport through the membrane occurs only for certain molecules and ions through membrane channels by means of diffusion or by active transport. However

Ljubljana, University of

65

pH dependence and compartmentalization of zinc transported across plasma membrane of rat cortical neurons  

E-Print Network [OSTI]

pH dependence and compartmentalization of zinc transported across plasma membrane of rat corticalH dependence and compartmental- ization of zinc transported across plasma membrane of rat cortical neurons. Am; ion transport; transition elements; primary culture IT IS KNOWN THAT Zn2 can enter neurons by two

66

Ionic transport in nanocapillary membrane systems Vikhram V. Swaminathan Larry R. Gibson II  

E-Print Network [OSTI]

. Keywords Membranes Á Nanostructures Á Nanofluidics Á Microfluidics Á Ion transport Á Electrokinetics Á lREVIEW Ionic transport in nanocapillary membrane systems Vikhram V. Swaminathan · Larry R. Gibson / Accepted: 23 May 2012 ? Springer Science+Business Media B.V. 2012 Abstract Species transport

67

Perchlorate Degradation Using Partially Oxidized Titanium Ions and Ion Exchange Membrane Hybrid System  

E-Print Network [OSTI]

. To enhance the overall rate of reaction, high concentrations of acid and Ti(III) are needed, but transport of hydrogen ions through the anion permeable membrane was observed and would be greater at higher acid concentrations. The proposed mathematical model...

Park, Sung Hyuk

2011-08-08T23:59:59.000Z

68

Facilitated transport of sodium or potassium chloride across vesicle membranes using a ditopic salt-binding macrobicycle  

E-Print Network [OSTI]

Facilitated transport of sodium or potassium chloride across vesicle membranes using a ditopic salt or potassium chloride as a contact ion-pair, is shown to effect- ively transport either salt across vesicle membranes. Sig- nificant transport is observed even when the transporter : phospholipid ratio is as low as 1

Smith, Bradley D.

69

Diffusion and selective transport of alkali cations on cation-exchange membrane  

SciTech Connect (OSTI)

The diffusion coefficients and selective transport for alkali metal cations through a charged polysulfonated ICE-450 ion-exchange membrane were measured as a function of pH at 25{degrees}C. The permeability and diffusion coefficients were found to increase in the sequence Cs{sup +} {ge} K{sup +} {ge} Na{sup +} {ge} Li{sup +}. The relationship between the permeability and the diffusion coefficients, and the hydrated radii of cations in the membrane were shown. This sequence was also explained by considering the hydration of ions in the membrane. The selectivity transport of K-Na and K-Li binary systems at various pH gradients through the membrane were also investigated under various conditions. In the selective transport of metal ions, the selectivity depended on both the hydrated ionic size and the interaction between the fixed groups in the membrane and the metal ions.

Ersoez, M. [Selcuk Univ., Konya (Turkey)

1995-11-01T23:59:59.000Z

70

Turbulent transport of energetic ions  

SciTech Connect (OSTI)

Approaching ITER operation, the issue of anomalous transport of fast particles becomes more and more important. This is partly because the ITER heating and current drive system relies heavily on neutral beam injection. Moreover burning plasmas are heated by fast fusion {alpha} particles.Fusion {alpha} particles are characterised by a fixed energy and an isotropic velocity distribution. Therefore they have gyroradii one magnitude larger than the thermal ions. The dependency of the particle diffusion of {alpha} test particles on the Kubo number K = VExB{tau}c/{lambda}c (VExB mean E x B velocity, {tau}c, {lambda}c correlation time and length of the turbulent potential) is presented. For different turbulent regimes, different dependency of the diffusion on the gyroradius is found. For large Kubo numbers, the transport is found to remain constant for gyroradii up to the correlation length of the potential, whereas it is drastically reduced in the small Kubo number regime.In the second part, a model for beam ions injected along the equilibrium magnetic field is described. The beam ions are treated gyrokinetically in a self-consistent way with the equilibrium distribution function taken as a shifted Maxwellian. The implications of such a model for the Vlasov equation, the field equations, and the calculation of moments and fluxes are discussed. Linear and nonlinear results, obtained with the gyrokinetic flux tube code GENE show the existence of a new instability driven by fast beam ions. The instability has a maximum growth rate at perpendicular wave numbers of ky{rho}s {approx} 0.15 and depends mainly on the beam velocity and the density gradient of the beam ions. This instability leads to a replacement of bulk ion particle transport by fast ion particle transport, connected to a strongly enhanced heat flux. In the presence of this instability, the turbulent particle and heat transport is dominated by fast ions.

Dannert, Tilman; Hauff, Thilo; Jenko, Frank; Guenter, Sibylle [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

2006-11-30T23:59:59.000Z

71

The Role of Sarcolipin and ATP in the Transport of Phosphate Ion into the Sarcoplasmic Reticulum  

E-Print Network [OSTI]

The Role of Sarcolipin and ATP in the Transport of Phosphate Ion into the Sarcoplasmic Reticulum toward chloride ion when incorporated in a mercury-supported tethered bilayer lipid membrane (tBLM). ItsM. Phenylphosphonium ion and adenosine monophosphate exert an inhibitory effect on membrane permeabilization

Thomas, David D.

72

Secondary ion collection and transport system for ion microprobe  

DOE Patents [OSTI]

A secondary ion collection and transport system, for use with an ion microprobe, which is very compact and occupies only a small working distance, thereby enabling the primary ion beam to have a short focal length and high resolution. Ions sputtered from the target surface by the primary beam's impact are collected between two arcuate members having radii of curvature and applied voltages that cause only ions within a specified energy band to be collected. The collected ions are accelerated and focused in a transport section consisting of a plurality of spaced conductive members which are coaxial with and distributed along the desired ion path. Relatively high voltages are applied to alternate transport sections to produce accelerating electric fields sufficient to transport the ions through the section to an ion mass analyzer, while lower voltages are applied to the other transport sections to focus the ions and bring their velocity to a level compatible with the analyzing apparatus.

Ward, James W. (Canoga Park, CA); Schlanger, Herbert (Simi Valley, CA); McNulty, Jr., Hugh (Santa Monica, CA); Parker, Norman W. (Camarillo, CA)

1985-01-01T23:59:59.000Z

73

Composite oxygen ion transport element  

SciTech Connect (OSTI)

A composite oxygen ion transport element that has a layered structure formed by a dense layer to transport oxygen ions and electrons and a porous support layer to provide mechanical support. The dense layer can be formed of a mixture of a mixed conductor, an ionic conductor, and a metal. The porous support layer can be fabricated from an oxide dispersion strengthened metal, a metal-reinforced intermetallic alloy, a boron-doped Mo.sub.5Si.sub.3-based intermetallic alloy or combinations thereof. The support layer can be provided with a network of non-interconnected pores and each of said pores communicates between opposite surfaces of said support layer. Such a support layer can be advantageously employed to reduce diffusion resistance in any type of element, including those using a different material makeup than that outlined above.

Chen, Jack C. (Getzville, NY); Besecker, Charles J. (Batavia, IL); Chen, Hancun (Williamsville, NY); Robinson, Earil T. (Mentor, OH)

2007-06-12T23:59:59.000Z

74

Electrolytic process to produce sodium hypochlorite using sodium ion conductive ceramic membranes  

DOE Patents [OSTI]

An electrochemical process for the production of sodium hypochlorite is disclosed. The process may potentially be used to produce sodium hypochlorite from seawater or low purity un-softened or NaCl-based salt solutions. The process utilizes a sodium ion conductive ceramic membrane, such as membranes based on NASICON-type materials, in an electrolytic cell. In the process, water is reduced at a cathode to form hydroxyl ions and hydrogen gas. Chloride ions from a sodium chloride solution are oxidized in the anolyte compartment to produce chlorine gas which reacts with water to produce hypochlorous and hydrochloric acid. Sodium ions are transported from the anolyte compartment to the catholyte compartment across the sodium ion conductive ceramic membrane. Sodium hydroxide is transported from the catholyte compartment to the anolyte compartment to produce sodium hypochlorite within the anolyte compartment.

Balagopal, Shekar; Malhotra, Vinod; Pendleton, Justin; Reid, Kathy Jo

2012-09-18T23:59:59.000Z

75

Alkylsulfonates as Probes of Uncoupling Protein Transport ION PAIR TRANSPORT DEMONSTRATES THAT DIRECT H TRANSLOCATION BY UCP1 IS NOT NECESSARY  

E-Print Network [OSTI]

Alkylsulfonates as Probes of Uncoupling Protein Transport Mechanism ION PAIR TRANSPORT DEMONSTRATES of Membrane Transport Biophysics, Institute of Physiology, Academy of Sciences, Prague 14220, Czech Republic is transported with the neutral ion pair, the sulfonate is able to deliver protons across the bilayer, behaving

Garlid, Keith

76

Characterization of ion selective membranes for application in reverse  

E-Print Network [OSTI]

Characterization of ion selective membranes for application in reverse electrodialysis systems I would have imagined when I started. i #12;Abstract Reverse electrodialysis (RED) is a renewable

Kjelstrup, Signe

77

The Mutation F227I Increases the Coupling of Metal Ion Transport in DCT1*  

E-Print Network [OSTI]

stoichiometry. At pH 7 and membrane potentials of 90 to 30 mV, DCT1 transports one Fe2 ion with one H . At highThe Mutation F227I Increases the Coupling of Metal Ion Transport in DCT1* Received for publication, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel Metal ion transport

Nelson, Nathan

78

Unique battery with an active membrane separator having uniform physico-chemically functionalized ion channels and a method making the same  

DOE Patents [OSTI]

The invention relates to a unique battery having an active, porous membrane and method of making the same. More specifically the invention relates to a sealed battery system having a porous, metal oxide membrane with uniform, physicochemically functionalized ion channels capable of adjustable ionic interaction. The physicochemically-active porous membrane purports dual functions: an electronic insulator (separator) and a unidirectional ion-transporter (electrolyte). The electrochemical cell membrane is activated for the transport of ions by contiguous ion coordination sites on the interior two-dimensional surfaces of the trans-membrane unidirectional pores. The membrane material is designed to have physicochemical interaction with ions. Control of the extent of the interactions between the ions and the interior pore walls of the membrane and other materials, chemicals, or structures contained within the pores provides adjustability of the ionic conductivity of the membrane.

Gerald, II, Rex E. (Brookfield, IL); Ruscic, Katarina J. (Chicago, IL); Sears, Devin N. (Spruce Grove, CA); Smith, Luis J. (Natick, MA); Klingler, Robert J. (Glenview, IL); Rathke, Jerome W. (Homer Glen, IL)

2012-02-21T23:59:59.000Z

79

Self-Energy-Limited Ion Transport in Subnanometer Channels Douwe Jan Bonthuis,1  

E-Print Network [OSTI]

Self-Energy-Limited Ion Transport in Subnanometer Channels Douwe Jan Bonthuis,1 Jingshan Zhang,2 -Hemolysin (-HL) pore embedded in an insulating phospholipid membrane. An ion current of I 80 pA is reduced, and a minimum of the current as a function of C. These observations are interpreted as the result of the ion

Meller, Amit

80

Dynamics of Ion Beam Stimulated Surface Mass Transport to Nanopores David P. Hoogerheide1  

E-Print Network [OSTI]

Dynamics of Ion Beam Stimulated Surface Mass Transport to Nanopores David P. Hoogerheide1 membrane, from the substrate side, by rastering a 10-nm diameter, 50 keV gallium ion beam produced by a FEI We explore the ion beam-induced dynamics of the formation of large features at the edges of nanopores

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Structures for Three Membrane Transport Proteins Yield Functional...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Structures for Three Membrane Transport Proteins Yield Functional Insights Print Cells depend on contact with their outside environment in order to thrive. Two examples illustrate...

82

ccsd-00014522,version1-5Oct2006 Co-transport-induced instability of membrane voltage in tip-growing cells  

E-Print Network [OSTI]

ccsd-00014522,version1-5Oct2006 Co-transport-induced instability of membrane voltage in tip at the same time. It is shown that these co-transporters destabilize generically the membrane voltage- tive dynamics and activity of membrane ion channels. Action potential and cardiac excitation spiral

Paris-Sud XI, Université de

83

Measurement of Water Transport Properties Through Membrane-Electrode Assemblies  

E-Print Network [OSTI]

a similar apparatus with Pd/H electrodes and obtained EOD equal to 2.5 and 0.9 at 30C for a fully hydratedMeasurement of Water Transport Properties Through Membrane-Electrode Assemblies I. Membranes of Ag/AgCl electrodes to derive a constant current across a membrane in contact on both sides with a 0

84

Contribution of calcium-conducting channels to the transport of zinc ions Alexandre Bouron 1,2,3  

E-Print Network [OSTI]

1 Contribution of calcium-conducting channels to the transport of zinc ions Alexandre Bouron 1. The mechanisms controlling its transport through the plasma membrane are far from being completely understood in the cellular uptake of zinc. These ion channels are currently described as systems dedicated to the transport

85

Correlation of Structural Differences between Nafion/Polyaniline and Nafion/Polypyrrole Composite Membranes and Observed Transport Properties  

SciTech Connect (OSTI)

Polyaniline/Nafion and polypyrrole/Nafion composite membranes, prepared by chemical polymerization, are studied by infrared and nuclear magnetic resonance spectroscopy, and scanning electron microscopy. Differences in vanadium ion diffusion through the membranes and in the membranes area specific resistance are linked to analytical observations that polyaniline and polypyrrole interact differently with Nafion. Polypyrrole, a weakly basic polymer, binds less strongly to the sulfonic acid groups of the Nafion membrane, and thus the hydrophobic polymer aggregates in the center of the Nafion channel rather than on the hydrophilic side chains of Nafion that contain sulfonic acid groups. This results in a drastically elevated membrane resistance and an only slightly decreased vanadium ion permeation compared to a Nafion membrane. Polyaniline on the other hand is a strongly basic polymer, which forms along the sidewalls of the Nafion pores and on the membrane surface, binding tightly to the sulfonic acid groups of Nafion. This leads to a more effective reduction in vanadium ion transport across the polyaniline/Nafion membranes and the increase in membrane resistance is less severe. The performance of selected polypyrrole/Nafion composite membranes is tested in a static vanadium redox cell. Increased coulombic efficiency, compared to a cell employing Nafion, further confirms the reduced vanadium ion transport through the composite membranes.

Schwenzer, Birgit; Kim, Soowhan; Vijayakumar, M.; Yang, Zhenguo; Liu, Jun

2011-04-15T23:59:59.000Z

86

On a novel rate theory for transport in narrow ion channels and its application to the study of flux optimization via geometric effects  

E-Print Network [OSTI]

On a novel rate theory for transport in narrow ion channels and its application to the study passage time to describe single-ion conduction in narrow, effectively one-dimensional membrane channels. DOI: 10.1063/1.3077205 I. INTRODUCTION Ion channels are membrane proteins which enable se- lected ions

Reingruber, Jürgen

87

Dynamics of a vesicle as a cell mimic: Effects of interior structure, cross-membrane transport, and interaction with filaments  

E-Print Network [OSTI]

Dynamics of a vesicle as a cell mimic: Effects of interior structure, cross-membrane transport, and interaction with filaments The biological membrane is, in essence, a thermodynamically-nonequilibrium lipid bilayer [6, 30, 34, 43, 47] with a variety of molecular motors, ion pumps, or channels residing within [19

Young, Yuan N.

88

Membranes for nanometer-scale mass fast transport  

DOE Patents [OSTI]

Nanoporous membranes comprising single walled, double walled, and multiwalled carbon nanotubes embedded in a matrix material were fabricated for fluid mechanics and mass transfer studies on the nanometer scale and commercial applications. Average pore size can be 2 nm to 20 nm, or seven nm or less, or two nanometers or less. The membrane can be free of large voids spanning the membrane such that transport of material such as gas or liquid occurs exclusively through the tubes. Fast fluid, vapor, and liquid transport are observed. Versatile micromachining methods can be used for membrane fabrication. A single chip can comprise multiple membranes. These membranes are a robust platform for the study of confined molecular transport, with applications in liquid and gas separations and chemical sensing including desalination, dialysis, and fabric formation.

Bakajin, Olgica (San Leandro, CA); Holt, Jason (Berkeley, CA); Noy, Aleksandr (Belmont, CA); Park, Hyung Gyu (Oakland, CA)

2011-10-18T23:59:59.000Z

89

Membrane porters of ATP-binding cassette transport systems are polyphyletic  

E-Print Network [OSTI]

in Membrane porters of ATP-binding cassette transportin Membrane porters of ATP-binding cassette transportin Membrane porters of ATP-binding cassette transport

Wang, Bin

2010-01-01T23:59:59.000Z

90

In-situ Investigation of Vanadium Ion Transport in Redox Flow Battery  

SciTech Connect (OSTI)

We will show a new method to differentiate the vanadium transport from concentration gradient and that from electric field. Flow batteries with vanadium and iron redox couples as the electro-active species were employed to investigate the transport behavior of vanadium ions in the presence of electric field. It was shown that electric field accelerated the positive-to-negative and reduced the negative-to-positive vanadium ions transport in charge process and affected the vanadium ions transport in an opposite way in discharge process. In addition, a method was designed to differentiate the concentration gradient-driven vanadium ions diffusion and electric field-driven vanadium ions migration. Simplified mathematical model was established to simulate the vanadium ions transport in real charge-discharge operation of flow battery. The concentration gradient diffusion coefficients and electric-migration coefficients of V2+, V3+, VO2+, and VO2+ across Nafion membrane were obtained by fitting the experimental data.

Luo, Qingtao; Li, Liyu; Nie, Zimin; Wang, Wei; Wei, Xiaoliang; Li, Bin; Chen, Baowei; Yang, Zhenguo

2012-06-27T23:59:59.000Z

91

Correlating Humidity-Dependent Ionically Conductive Surface Area with Transport Phenomena in Proton-Exchange Membranes  

SciTech Connect (OSTI)

The objective of this effort was to correlate the local surface ionic conductance of a Nafion? 212 proton-exchange membrane with its bulk and interfacial transport properties as a function of water content. Both macroscopic and microscopic proton conductivities were investigated at different relative humidity levels, using electrochemical impedance spectroscopy and current-sensing atomic force microscopy (CSAFM). We were able to identify small ion-conducting domains that grew with humidity at the surface of the membrane. Numerical analysis of the surface ionic conductance images recorded at various relative humidity levels helped determine the fractional area of ion-conducting active sites. A simple square-root relationship between the fractional conducting area and observed interfacial mass-transport resistance was established. Furthermore, the relationship between the bulk ionic conductivity and surface ionic conductance pattern of the Nafion? membrane was examined.

He, Qinggang; Kusoglu, Ahmet; Lucas, Ivan T.; Clark, Kyle; Weber, Adam Z.; Kostecki, Robert

2011-08-01T23:59:59.000Z

92

Interfacial Water-Transport Effects in Proton-Exchange Membranes  

SciTech Connect (OSTI)

It is well known that the proton-exchange membrane is perhaps the most critical component of a polymer-electrolyte fuel cell. Typical membranes, such as Nafion(R), require hydration to conduct efficiently and are instrumental in cell water management. Recently, evidence has been shown that these membranes might have different interfacial morphology and transport properties than in the bulk. In this paper, experimental data combined with theoretical simulations will be presented that explore the existence and impact of interfacial resistance on water transport for Nafion(R) 21x membranes. A mass-transfer coefficient for the interfacial resistance is calculated from experimental data using different permeation cells. This coefficient is shown to depend exponentially on relative humidity or water activity. The interfacial resistance does not seem to exist for liquid/membrane or membrane/membrane interfaces. The effect of the interfacial resistance is to flatten the water-content profiles within the membrane during operation. Under typical operating conditions, the resistance is on par with the water-transport resistance of the bulk membrane. Thus, the interfacial resistance can be dominant especially in thin, dry membranes and can affect overall fuel-cell performance.

Kienitz, Brian; Yamada, Haruhiko; Nonoyama, Nobuaki; Weber, Adam

2009-11-19T23:59:59.000Z

93

Topical Review Fluctuations and Fractal Noise in Biological Membranes  

E-Print Network [OSTI]

and transport of ions and molecules across biological membranes. We know that ion transport through mem- branes in electrical properties associated with cell membrane ion transport. Key words: Brownian motion -- Cell membrane elec- trical properties -- Fractals -- Gaussian noise -- Ion transport -- Nonlinear dynamics

94

Membrane permeation process for dehydration of organic liquid mixtures using sulfonated ion-exchange polyalkene membranes  

DOE Patents [OSTI]

A membrane permeation process for dehydrating a mixture of organic liquids, such as alcohols or close boiling, heat sensitive mixtures. The process comprises causing a component of the mixture to selectively sorb into one side of sulfonated ion-exchange polyalkene (e.g., polyethylene) membranes and selectively diffuse or flow therethrough, and then desorbing the component into a gas or liquid phase on the other side of the membranes.

Cabasso, Israel (131 Buckingham Ave., Syracuse, NY 13210); Korngold, Emmanuel (P.O. Box 1025, Beer-Sheva 84110, IL)

1988-01-01T23:59:59.000Z

95

Universality of Poisson Indicator and Fano Factor of Transport Event Statistics in Ion Channels and Enzyme Kinetics  

E-Print Network [OSTI]

Universality of Poisson Indicator and Fano Factor of Transport Event Statistics in Ion Channels transport has been the steady state flux in a single channel through a membrane that separates two, Cambridge, Massachusetts, 02139 United States ABSTRACT: We consider a generic stochastic model of ion

Cao, Jianshu

96

Dr. Ing. /PhD / Dr.techn. Students supervised by Signe Kjelstrup 1. Torleif Holt, Transport and equilibrium properties of a cation exchange membrane (1983)  

E-Print Network [OSTI]

, (1996) 6. Magnar Ottøy, Mass and heat transfer in ion-exchange membranes (1996) 7. Belinda Flem, Peltier in the Polymer Electrolyte Membrane Fuel Cell (2007) 17. Isabella Inzoli, Coupled transports of heat and massDr. Ing. /PhD / Dr.techn. Students supervised by Signe Kjelstrup 1. Torleif Holt, Transport

Kjelstrup, Signe

97

Engineering Development of Ceramic Membrane Reactor System for Converting Natural Gas to Hydrogen and Synthesis Gas for Liquid Transportation Fuels  

SciTech Connect (OSTI)

An Air Products-led team successfully developed ITM Syngas technology from the concept stage to a stage where a small-scale engineering prototype was about to be built. This technology produces syngas, a gas containing carbon monoxide and hydrogen, by reacting feed gas, primarily methane and steam, with oxygen that is supplied through an ion transport membrane. An ion transport membrane operates at high temperature and oxygen ions are transported through the dense membrane's crystal lattice when an oxygen partial pressure driving force is applied. This development effort solved many significant technical challenges and successfully scaled-up key aspects of the technology to prototype scale. Throughout the project life, the technology showed significant economic benefits over conventional technologies. While there are still on-going technical challenges to overcome, the progress made under the DOE-funded development project proved that the technology was viable and continued development post the DOE agreement would be warranted.

Air Products and Chemicals

2008-09-30T23:59:59.000Z

98

Development of active-transport membrane devices  

SciTech Connect (OSTI)

This report introduces the concept of Air Products` AT membranes for the separation of NH{sub 3} and CO{sub 2} from process gas streams and presents results from the first year fabrication concept development studies.

Laciak, D.V.

1994-07-01T23:59:59.000Z

99

Salt Concentration Differences Alter Membrane Resistance in Reverse Electrodialysis Stacks  

E-Print Network [OSTI]

,3,4 Selective transport of ions through the membranes creates an electric potential across pairs of AEMs by changing the membrane polymer chemistry and/or membrane form factor.9-13 The ion transport properties on either side of the membrane on ion transport properties must be studied to improve our under- standing

100

Hydrogen transport membranes for dehydrogenation reactions  

DOE Patents [OSTI]

A method of converting C.sub.2 and/or higher alkanes to olefins by contacting a feedstock containing C.sub.2 and/or higher alkanes with a first surface of a metal composite membrane of a sintered homogenous mixture of an Al oxide or stabilized or partially stabilized Zr oxide ceramic powder and a metal powder of one or more of Pd, Nb, V, Zr, Ta and/or alloys or mixtures thereof. The alkanes dehydrogenate to olefins by contact with the first surface with substantially only atomic hydrogen from the dehydrogenation of the alkanes passing through the metal composite membrane. Apparatus for effecting the conversion and separation is also disclosed.

Balachandran; Uthamalingam (Hinsdale, IL)

2008-02-12T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

High-powered pulsed-ion-beam acceleration and transport  

SciTech Connect (OSTI)

The state of research on intense ion beam acceleration and transport is reviewed. The limitations imposed on ion beam transport by space charge effects and methods available for neutralization are summarized. The general problem of ion beam neutralization in regions free of applied electric fields is treated. The physics of acceleration gaps is described. Finally, experiments on multi-stage ion acceleration are summarized.

Humphries, S. Jr.; Lockner, T.R.

1981-11-01T23:59:59.000Z

102

MEMBRANE FUNCTION, Part 2. Passive Movement: Diffusion, Osmosis, and Gibbs-Donnan Equilibrium 1  

E-Print Network [OSTI]

such as ion gradients or sunlight. I. Passive transport Passive transport is diffusion through a membrane of the membrane. This movement is entirely by the process of diffusion (to be covered below) · ions and polar. Mechanisms of Membrane Transport There are two general modes of transport across membranes: passive transport

Prestwich, Ken

103

Operation of staged membrane oxidation reactor systems  

SciTech Connect (OSTI)

A method of operating a multi-stage ion transport membrane oxidation system. The method comprises providing a multi-stage ion transport membrane oxidation system with at least a first membrane oxidation stage and a second membrane oxidation stage, operating the ion transport membrane oxidation system at operating conditions including a characteristic temperature of the first membrane oxidation stage and a characteristic temperature of the second membrane oxidation stage; and controlling the production capacity and/or the product quality by changing the characteristic temperature of the first membrane oxidation stage and/or changing the characteristic temperature of the second membrane oxidation stage.

Repasky, John Michael

2012-10-16T23:59:59.000Z

104

Multicomponent Transport through Realistic Zeolite Membranes: Characterization & Transport in Nanoporous Networks  

SciTech Connect (OSTI)

These research studies focused on the characterization and transport for porous solids which comprise both microporosity and mesoporosity. Such materials represent membranes made from zeolites as well as for many new nanoporous solids. Several analytical sorption techniques were developed and evaluated by which these multi-dimensional porous solids could be quantitatively characterized. Notably an approach by which intact membranes could be studied was developed and applied to plate-like and tubular supported zeolitic membranes. Transport processes were studied experimentally and theoretically based on the characterization studies.

William C. Conner

2007-08-02T23:59:59.000Z

105

ADVANCED HYDROGEN TRANSPORT MEMBRANES FOR VISION 21 FOSSIL FUEL PLANTS  

SciTech Connect (OSTI)

Eltron Research Inc., and team members, are developing an environmentally benign, inexpensive, and efficient method for separating hydrogen from gas mixtures produced during industrial processes, such as coal gasification. This project was motivated by the National Energy Technology Laboratory (NETL) Vision 21 initiative which seeks to economically eliminate environmental concerns associated with the use of fossil fuels. This objective is being pursued using dense membranes based in part on Eltron-patented ceramic materials with a demonstrated ability for proton and electron conduction. The technical goals are being addressed by modifying single-phase and composite membrane composition and microstructure to maximize proton and electron conductivity without loss of material stability. Ultimately, these materials must enable hydrogen separation at practical rates under ambient and high-pressure conditions, without deactivation in the presence of feedstream components such as carbon dioxide, water, and sulfur. During this quarter, ceramic, cermet (ceramic/metal), and thin film membranes were prepared, characterized, and evaluated for H{sub 2} transport. For selected ceramic membrane compositions an optimum range for transition metal doping was identified, and it was determined that highest proton conductivity occurred for two-phase ceramic materials. Furthermore, a relationship between transition metal dopant atomic number and conductivity was observed. Ambipolar conductivities of {approx}6 x 10{sup -3} S/cm were achieved for these materials, and {approx} 1-mm thick membranes generated H{sub 2} transport rates as high as 0.3 mL/min/cm{sup 2}. Cermet membranes during this quarter were found to have a maximum conductivity of 3 x 10{sup -3} S/cm, which occurred at a metal phase contact of 36 vol.%. Homogeneous dense thin films were successfully prepared by tape casting and spin coating; however, there remains an unacceptably high difference in shrinkage rates between the film and support, which led to membrane instability. Further improvements in high pressure membrane seals also were achieved during this quarter, and a maximum pressure of 100 psig was attained. CoorsTek optimized many of the processing variables relevant to manufacturing scale production of ceramic H{sub 2} transport membranes, and SCI used their expertise to deposit a range of catalysts compositions onto ceramic membrane surfaces. Finally, MTI compiled relevant information regarding Vision 21 fossil fuel plant operation parameters, which will be used as a starting point for assessing the economics of incorporating a H{sub 2} separation unit.

Shane E. Roark; Tony F. Sammells; Richard A. Mackay; Adam E. Calihman; Lyrik Y. Pitzman; Tom F. Barton; Sara L. Rolfe; Richard N. Kleiner; James E. Stephan; Mike J. Holmes; Aaron L. Wagner

2001-07-30T23:59:59.000Z

106

Engineering Development of Ceramic Membrane Reactor  

E-Print Network [OSTI]

ceramic Ion Transport Membrane (ITM) reactor system for low-cost conversion of natural gas to hydrogen;7 A Revolutionary Technology Using Ceramic Membranes Ion Transport Membranes (ITM) ­ Non-porous multiEngineering Development of Ceramic Membrane Reactor Systems for Converting Natural Gas to Hydrogen

107

Ion transport through a graphene nanopore  

E-Print Network [OSTI]

Molecular dynamics simulation is utilized to investigate the ionic transport of NaCl in solution through a graphene nanopore under an applied electric field. Results show the formation of concentration polarization layers in the vicinity of the graphene sheet. The non-uniformity of the ion distribution gives rise to an electric pressure which drives vortical motions in the fluid if the electric field is sufficiently strong to overcome the influence of viscosity and thermal fluctuations. The relative importance of hydrodynamic transport and thermal fluctuations in determining the pore conductivity is investigated. A second important effect that is observed is the mass transport of water through the nanopore, with an average velocity proportional to the applied voltage and independent of the pore diameter. The flux arises as a consequence of the asymmetry in the ion distribution with respect to reflection about the plane of the graphene sheet. The accumulation of liquid molecules in the vicinity of the nanopore due to reorientation of the water dipoles by the local electric field is seen to result in a local increasein the liquid density. Results confirm that the electric conductance is proportional to the nanopore diameter for the parameter regimes that we simulated. The occurrence of fluid vortices is found to result in an increase in the effective electrical conductance.

Guohui Hu; Mao Mao; Sandip Ghosal

2013-01-09T23:59:59.000Z

108

VOLUME 80, NUMBER 20 P H Y S I C A L R E V I E W L E T T E R S 18 MAY 1998 Spontaneous Onset of Coherence and Energy Storage by Membrane Transporters  

E-Print Network [OSTI]

of Coherence and Energy Storage by Membrane Transporters in an RLC Electric Circuit Imre Derényi and R. Dean that oscillating or fluctuating electric fields can drive thermodynami- cally uphill transport of ions catalyzed by a molecular ion pump, the Na,K-ATPase. Theory suggests that if the transport reaction is very far from

Derényi, Imre

109

ADVANCED HYDROGEN TRANSPORT MEMBRANES FOR VISION 21 FOSSIL FUEL PLANTS  

SciTech Connect (OSTI)

Eltron Research Inc., and team members CoorsTek, McDermott Technology, Inc., Sued Chemie, Argonne National Laboratory and Oak Ridge National Laboratory are developing an environmentally benign, inexpensive, and efficient method for separating hydrogen from gas mixtures produced during industrial processes, such as coal gasification. This project was motivated by the National Energy Technology Laboratory (NETL) Vision 21 initiative which seeks to economically eliminate environmental concerns associated with the use of fossil fuels. This objective is being pursued using dense membranes based in part on Eltron-patented ceramic materials with a demonstrated ability for proton and electron conduction. The technical goals are being addressed by modifying single-phase and composite membrane composition and microstructure to maximize proton and electron conductivity without loss of material stability. Ultimately, these materials must enable hydrogen separation at practical rates under ambient and high-pressure conditions, without deactivation in the presence of feedstream components such as carbon dioxide, water, and sulfur. During this quarter, mixed proton/electron conductivity and hydrogen transport was measured as a function of metal phase content for a range of ceramic/metal (cermet) compositions. It was found that optimum performance occurred at 44 wt.% metal content for all compositions tested. Although each cermet appeared to have a continuous metal phase, it is believed that hydrogen transport increased with increasing metal content partially due to beneficial surface catalyst characteristics resulting from the metal phase. Beyond 44 wt.% there was a reduction in hydrogen transport most likely due to dilution of the proton conducting ceramic phase. Hydrogen separation rates for 1-mm thick cermet membranes were in excess of 0.1 mL/min/cm{sup 2}, which corresponded to ambipolar conductivities between 1 x 10{sup -3} and 8 x 10{sup -3} S/cm. Similar results were obtained for multiphase ceramic membranes comprised of a proton-conducting perovskite and electron conducting metal oxide. These multi-phase ceramic membranes showed only a slight improvement in hydrogen transport upon addition of a metal phase. The highest hydrogen separation rates observed this quarter were for a cermet membrane containing a hydrogen transport metal. A 1-mm thick membrane of this material achieved a hydrogen separation rate of 0.3 mL/min/cm{sup 2} at only 700 C, which increased to 0.6 mL/min/cm{sup 2} at 950 C.

Shane E. Roark; Tony F. Sammells; Richard A. Mackay; Lyrik Y. Pitzman; Alexandra Z. LaGuardia; Tom F. Barton; Sara L. Rolfe; Richard N. Kleiner; James E. Stephan; Mike J. Holmes; Aaron L. Wagner

2001-10-30T23:59:59.000Z

110

Ballistic electron transport in structured suspended semiconductor membranes  

SciTech Connect (OSTI)

We study ballistic electron transport in freely suspended AlAs/GaAs microstructures containing a high mobility two-dimensional electron gas with square lattice of antidots. We found that the magnetoresistance of the samples demonstrates commensurability oscillations both for the case of non-suspended and suspended devices. The temperature dependence of the commensurability oscillations is similar for both cases. However, the critical dc current, that suppresses these oscillations, in suspended samples is three times lower than in non-suspended ones. The observed phenomenon can be explained by peculiarities of the heat transport in membranes.

Pogosov, A. G.; Budantsev, M. V.; Zhdanov, E. Yu.; Pokhabov, D. A. [Institute of Semiconductor Physics SB RAS, Novosibirsk, Russia and Novosibirsk State University, Novosibirsk (Russian Federation)

2013-12-04T23:59:59.000Z

111

alters ion transport: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and fuel (mostly methane) conversion purposes over the last three decades. The fuel ... Apo, Daniel Jolomi 2012-01-01 42 Particle transport and ion current rectification in...

112

Perspective Ion Channels: From Conductance to Structure  

E-Print Network [OSTI]

membrane is an essen- tially insurmountable barrier for the flow of ions; therefore, ion transport is carried out by membrane-embedded specialized proteins in the form of transporters and ion channels a purely electrical concept to a structural dynamics view of ions in- teracting with a membrane protein

Bezanilla, Francisco

113

Surface-Modified Membrane as A Separator for Lithium-Ion Polymer Battery  

E-Print Network [OSTI]

This paper describes the fabrication of novel modified polyethylene (PE) membranes using plasma technology to create high-performance and cost-effective separator membranes for practical applications in lithium-ion polymer ...

Kim, Jun Young

114

ADVANCED HYDROGEN TRANSPORT MEMBRANES FOR VISION 21 FOSSIL FUEL PLANTS  

SciTech Connect (OSTI)

Eltron Research Inc. and their team members are developing an environmentally benign, inexpensive, and efficient method for separating hydrogen from gas mixtures produced during industrial processes, such as coal gasification. This project was motivated by the National Energy Technology Laboratory (NETL) Vision 21 initiative which seeks to economically eliminate environmental concerns associated with the use of fossil fuels. This objective is being pursued using dense membranes based in part on Eltron-patented ceramic materials with a demonstrated ability for proton and electron conduction. The technical goals are being addressed by modifying single-phase and composite membrane composition and microstructure to maximize proton and electron conductivity without loss of material stability. Ultimately, these materials must enable hydrogen separation at practical rates under ambient and high-pressure conditions, without deactivation in the presence of feedstream components such as carbon dioxide, water, and sulfur. During this quarter, new cermet compositions were tested that demonstrated similar performance to previous materials. A 0.5-mm thick membrane achieved at H{sub 2} transport rate of 0.2 mL/min/cm{sup 2} at 950 C, which corresponded to an ambipolar conductivity of 3 x 10{sup -3} S/cm. Although these results were equivalent to those for other cermet compositions, this new composition might be useful if it demonstrates improved chemical or mechanical stability. Ceramic/ceramic composite membranes also were fabricated and tested; however, some reaction did occur between the proton- and electron-conducting phases, which likely compromised conductivity. This sample only achieved a H{sub 2} transport rate of {approx} 0.006 mL/min/cm{sup 2} and an ambipolar conductivity of {approx}4 x 10{sup -4} S/cm. Chemical stability tests were continued, and candidate ceramic membranes were found to react slightly with carbon monoxide under extreme testing conditions. A cermet compositions did not show any reaction with carbon monoxide, but a thick layer of carbon formed on the membrane surface. The most significant technical accomplishment this quarter was a new high-pressure seal composition. This material maintained a pressure differential across the membrane of {approx} 280 psi at 800 C, and is still in operation.

Shane E. Roark; Anthony F. Sammells; Richard A. Mackay; Lyrik Y. Pitzman; Thomas A. Zirbel; Thomas F. Barton; Sara L. Rolfe; U. (Balu) Balachandran; Richard N. Kleiner; James E. Stephan; Frank E. Anderson; George Farthing; Dan Rowley; Tim R. Armstrong; M.K. Ferber; Aaron L. Wagner; Jon P. Wagner

2002-07-30T23:59:59.000Z

115

Proton Transport and the Water Environment in Nafion Fuel Cell Membranes and AOT Reverse Micelles  

E-Print Network [OSTI]

Proton Transport and the Water Environment in Nafion Fuel Cell Membranes and AOT Reverse Micelles D channels of Nafion fuel cell membranes at various hydration levels are compared to water in a series by its use as a proton conducting membrane in fuel cells. Nafion membranes in fuel cells allow protons

Fayer, Michael D.

116

Crystal Structure of a Potassium Ion Transporter TrkH  

SciTech Connect (OSTI)

The TrkH/TrkG/KtrB proteins mediate K{sup +} uptake in bacteria and probably evolved from simple K{sup +} channels by multiple gene duplications or fusions. Here we present the crystal structure of a TrkH from Vibrio parahaemolyticus. TrkH is a homodimer, and each protomer contains an ion permeation pathway. A selectivity filter, similar in architecture to those of K{sup +} channels but significantly shorter, is lined by backbone and side-chain oxygen atoms. Functional studies showed that TrkH is selective for permeation of K{sup +} and Rb{sup +} over smaller ions such as Na{sup +} or Li{sup +}. Immediately intracellular to the selectivity filter are an intramembrane loop and an arginine residue, both highly conserved, which constrict the permeation pathway. Substituting the arginine with an alanine significantly increases the rate of K{sup +} flux. These results reveal the molecular basis of K{sup +} selectivity and suggest a novel gating mechanism for this large and important family of membrane transport proteins.

Y Cao; X Jin; H Huang; M Getahun Derebe; E Levin; V Kabaleeswaran; Y Pan; M Punta; J Love; et al.

2011-12-31T23:59:59.000Z

117

Reactive ion etching: Optimized diamond membrane fabrication for transmission electron microscopy  

E-Print Network [OSTI]

Commonly used preparation method for thin diamond membranes by focused ion beam (FIB) techniques results in surface damage. Here, the authors introduce an alternative method based on reactive ion etching (RIE). To compare ...

Li, Luozhou

118

Controlling polymer translocation and ion transport via charge correlations  

E-Print Network [OSTI]

We develop a correlation-corrected transport theory in order to predict ionic and polymer transport properties of membrane nanopores in physical conditions where mean-field electrostatics breaks down. The experimentally observed low KCl conductivity of open alpha-Hemolysin pores is quantitatively explained by the presence of surface polarization effects. Upon the penetration of a DNA molecule into the pore, these polarization forces combined with the electroneutrality of DNA sets a lower boundary for the ionic current, explaining the weak salt dependence of blocked pore conductivities at dilute ion concentrations. The addition of multivalent counterions into the solution results in the reversal of the polymer charge and the direction of the electroosmotic flow. With trivalent spermidine or quadrivalent spermine molecules, the charge inversion is strong enough to stop the translocation of the polymer and to reverse its motion. This mechanism can be used efficiently in translocation experiments in order to improve the accuracy of DNA sequencing by minimizing the translocation velocity of the polymer.

Sahin Buyukdagli; Tapio Ala-Nissila

2014-10-10T23:59:59.000Z

119

Polymer electrolyte membranes from fluorinated polyisoprene-block-sulfonated polystyrene: Membrane structure and transport properties  

SciTech Connect (OSTI)

With a view to optimizing morphology and ultimately properties, membranes have been cast from relatively inexpensive block copolymer ionomers of fluorinated polyisoprene-block-sulfonated polystyrene (FISS) with various sulfonation levels, in both the acid form and the cesium neutralized form. The morphology of these membranes was characterized by transmission electron microscopy and ultra-small angle X-ray scattering, as well as water uptake, proton conductivity and methanol permeability within the temperature range from 20 to 60 C. Random phase separated morphologies were obtained for all samples except the cesium sample with 50 mol% sulfonation. The transport properties increased with increasing degree of sulfonation and temperature for all samples. The acid form samples absorbed more water than the cesium samples with a maximum swelling of 595% recorded at 60 C for the acid sample having 50 mol% sulfonation. Methanol permeability for the latter sample was more than an order of magnitude less than for Nafion 112 but so was the proton conductivity within the plane of the membrane at 20 C. Across the plane of the membrane this sample had half the conductivity of Nafion 112 at 60 C.

Sodeye, Akinbode [Department of Polymer Science and Engineering, University of Massachusetts; Huang, Tianzi [University of Tennessee, Knoxville (UTK); Gido, Samuel [University of Massachusetts, Amherst; Mays, Jimmy [ORNL

2011-01-01T23:59:59.000Z

120

The Structure and Transport of Water and Hydrated Ions Within Hydrophobic, Nanoscale Channels  

SciTech Connect (OSTI)

The purpose of this project includes an experimental and modeling investigation into water and hydrated ion structure and transport at nanomaterials interfaces. This is a topic relevant to understanding the function of many biological systems such as aquaporins that efficiently shuttle water and ion channels that permit selective transport of specific ions across cell membranes. Carbon nanotubes (CNT) are model nanoscale, hydrophobic channels that can be functionalized, making them artificial analogs for these biological channels. This project investigates the microscopic properties of water such as water density distributions and dynamics within CNTs using Nuclear Magnetic Resonance (NMR) and the structure of hydrated ions at CNT interfaces via X-ray Absorption Spectroscopy (XAS). Another component of this work is molecular simulation, which can predict experimental measurables such as the proton relaxation times, chemical shifts, and can compute the electronic structure of CNTs. Some of the fundamental questions this work is addressing are: (1) what is the length scale below which nanoscale effects such as molecular ordering become important, (2) is there a relationship between molecular ordering and transport?, and (3) how do ions interact with CNT interfaces? These are questions of interest to the scientific community, but they also impact the future generation of sensors, filters, and other devices that operate on the nanometer length scale. To enable some of the proposed applications of CNTs as ion filtration media and electrolytic supercapacitors, a detailed knowledge of water and ion structure at CNT interfaces is critical.

Holt, J K; Herberg, J L; Wu, Y; Schwegler, E; Mehta, A

2009-06-15T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

E-Print Network 3.0 - aeruginosa membrane transport Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

U. The membrane-bound electron transport system of Methanosarcina species. J. Bioenerg. Biomembr... of methanophenazine and function of phenazines in ... Source: Dietrich,...

122

E-Print Network 3.0 - active transport membrane Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

84 CURRICULUM VITAE JOHN PETER PALMERI Summary: Membrane Transport Theory Dual American-French Nationality PROFESSIONAL ADDRESS Laboratoire de Physique... of Montpellier II,...

123

ATP-binding cassette-like transporters are involved in the transport of lignin precursors across plasma and vacuolar membranes  

SciTech Connect (OSTI)

Lignin is a complex biopolymer derived primarily from the condensation of three monomeric precursors, the monolignols. The synthesis of monolignols occurs in the cytoplasm. To reach the cell wall where they are oxidized and polymerized, they must be transported across the cell membrane. However, the molecular mechanisms underlying the transport process are unclear. There are conflicting views about whether the transport of these precursors occurs by passive diffusion or is an energized active process; further, we know little about what chemical forms are required. Using isolated plasma and vacuolar membrane vesicles prepared from Arabidopsis, together with applying different transporter inhibitors in the assays, we examined the uptake of monolignols and their derivatives by these native membrane vesicles. We demonstrate that the transport of lignin precursors across plasmalemma and their sequestration into vacuoles are ATP-dependent primary-transport processes, involving ATP-binding cassette-like transporters. Moreover, we show that both plasma and vacuolar membrane vesicles selectively transport different forms of lignin precursors. In the presence of ATP, the inverted plasma membrane vesicles preferentially take up monolignol aglycones, whereas the vacuolar vesicles are more specific for glucoconjugates, suggesting that the different ATP-binding cassette-like transporters recognize different chemical forms in conveying them to distinct sites, and that glucosylation of monolignols is necessary for their vacuolar storage but not required for direct transport into the cell wall in Arabidopsis.

Miao, Y.C.; Liu, C.

2010-12-28T23:59:59.000Z

124

Boltzmann-Langevin transport model for heavy-ion collisions  

SciTech Connect (OSTI)

Heavy-ion collisions at intermediate energies exhibit catastrophic phenomena which requires descriptions based on stochastic transport models. First, the Boltzmann-Langevin model, which provides an example of such stochastic approaches, is briefly described. Then, a projection method for obtaining numerical solutions of the Boltzmann-Langevin equation is discussed. Finally, some applications of the model to heavy-ion collisions are presented.

Ayik, S. [Tennessee Technological Univ., Cookeville, TN (United States)]|[Joint Institute for Heavy-Ion Research, Oak Ridge, TN (United States)

1994-06-01T23:59:59.000Z

125

Ion-exchange selectivities of periderm and cuticular membranes toward alkali cations  

SciTech Connect (OSTI)

The ion-exchange selectivities of lithium, sodium, potassium, and cesium on isolated potato periderm (Solanum tuberosum) and pear fruit cuticular membranes were investigated; the general order of preference both for cation selectivities and ion-exchange capacities was lithium > sodium > potassium > cesium. The potato periderm and pear fruit cuticular membranes exhibited a behavior typical of ion-exchange resins of the weak acid type. At constant pH 7, the ion-exchange capacities of periderm and cuticular membranes increased with hydrated ionic radius, and also with increasing pH and neutral salt concentration, and decreased with crystal ionic radius. Counterion selectivities also exhibited the same behavior. The ion-exchange properties are discussed in terms of the structure and function of potato periderm and pear fruit cuticular membranes.

Ersoz, M. [Univ. of Selcuk, Konya (Turkey); Duncan, H.J. [Univ. of Glasgow, Scotland (United Kingdom)

1994-08-01T23:59:59.000Z

126

Benchmarking of Neutron Production of Heavy-Ion Transport Codes  

SciTech Connect (OSTI)

Accurate prediction of radiation fields generated by heavy ion interactions is important in medical applications, space missions, and in design and operation of rare isotope research facilities. In recent years, several well-established computer codes in widespread use for particle and radiation transport calculations have been equipped with the capability to simulate heavy ion transport and interactions. To assess and validate these capabilities, we performed simulations of a series of benchmark-quality heavy ion experiments with the computer codes FLUKA, MARS15, MCNPX, and PHITS. We focus on the comparisons of secondary neutron production. Results are encouraging; however, further improvements in models and codes and additional benchmarking are required.

Remec, Igor [ORNL; Ronningen, Reginald M. [Michigan State University, East Lansing; Heilbronn, Lawrence [University of Tennessee, Knoxville (UTK)

2012-01-01T23:59:59.000Z

127

Effective Transport Properties Accounting for Electrochemical Reactions of Proton-Exchange Membrane Fuel Cell Catalyst Layers  

SciTech Connect (OSTI)

There has been a rapidly growing interest in three-dimensional micro-structural reconstruction of fuel cell electrodes so as to derive more accurate descriptors of the pertinent geometric and effective transport properties. Due to the limited accessibility of experiments based reconstruction techniques, such as dual-beam focused ion beam-scanning electro microscopy or micro X-Ray computed tomography, within sample micro-structures of the catalyst layers in polymer electrolyte membrane fuel cells (PEMFCs), a particle based numerical model is used in this study to reconstruct sample microstructure of the catalyst layers in PEMFCs. Then the reconstructed sample structure is converted into the computational grid using body-fitted/cut-cell based unstructured meshing technique. Finally, finite volume methods (FVM) are applied to calculate effective properties on computational sample domains.

Pharoah, Jon; Choi, Hae-Won; Chueh, Chih-Che; Harvey, David

2011-07-01T23:59:59.000Z

128

Oxygen transport membrane system and method for transferring heat to catalytic/process reactors  

DOE Patents [OSTI]

A method and apparatus for producing heat used in a synthesis gas production is provided. The disclosed method and apparatus include a plurality of tubular oxygen transport membrane elements adapted to separate oxygen from an oxygen containing stream contacting the retentate side of the membrane elements. The permeated oxygen is combusted with a hydrogen containing synthesis gas stream contacting the permeate side of the tubular oxygen transport membrane elements thereby generating a reaction product stream and radiant heat. The present method and apparatus also includes at least one catalytic reactor containing a catalyst to promote the stream reforming reaction wherein the catalytic reactor is surrounded by the plurality of tubular oxygen transport membrane elements. The view factor between the catalytic reactor and the plurality of tubular oxygen transport membrane elements radiating heat to the catalytic reactor is greater than or equal to 0.5.

Kelly, Sean M; Kromer, Brian R; Litwin, Michael M; Rosen, Lee J; Christie, Gervase Maxwell; Wilson, Jamie R; Kosowski, Lawrence W; Robinson, Charles

2014-01-07T23:59:59.000Z

129

The Dynamics of Platinum Precipitation in an Ion Exchange Membrane  

E-Print Network [OSTI]

Microscopy of polymer electrolyte membranes that have undergone operation under fuel cell conditions, have revealed a well defined band of platinum in the membrane. Here, we propose a physics based model that captures the mechanism of platinum precipitation in the polymer electrolyte membrane. While platinum is observed throughout the membrane, the preferential growth of platinum at the band of platinum is dependent on the electrochemical potential distribution in the membrane. In this paper, the location of the platinum band is calculated as a function of the gas concentration at the cathode and anode, gas diffusion coefficients and solubility constants of the gases in the membrane, which are functions of relative humidity. Under H2/N2 conditions the platinum band is located near the cathode-membrane interface, as the oxygen concentration in the cathode gas stream increases and/or the hydrogen concentration in the anode gas stream decreases, the band moves towards the anode. The model developed in this paper...

Burlatsky, S F; Atrazhev, V V; Dmitriev, D V; Kuzminyh, N Y; Erikhman, N S

2013-01-01T23:59:59.000Z

130

Patterned ion exchange membranes for improved power production in microbial reverse-electrodialysis cells  

E-Print Network [OSTI]

Patterned ion exchange membranes for improved power production in microbial reverse-electrodialysis August 2014 Keywords: Microbial reverse electrodialysis cell Patterned membranes Integrated spacer Internal resistance a b s t r a c t Power production in microbial reverse-electrodialysis cells (MRCs) can

131

Interfacial Water-Transport Effects in Proton-Exchange Membranes  

E-Print Network [OSTI]

MaterialsModelinginPemFuelCells,A CombinationModelIonomerMembranesforPem?FuelCells,"ElectrochimicaActa,

Kienitz, Brian

2010-01-01T23:59:59.000Z

132

THE VITELLINE MEMBRANE OF THE UNFERTILIZED HEN'S EGG  

E-Print Network [OSTI]

membrane is charged and asymmetrical. It's directional specificity to ion transport and accompanying volumeTHE VITELLINE MEMBRANE OF THE UNFERTILIZED HEN'S EGG : ELECTROLYTE AND WATER TRANSPORT T. RYMEN J more than just the result of the membrane's ion exchange behaviour and that it may involve an enzymatic

Paris-Sud XI, Université de

133

The role of space charge compensation for ion beam extraction and ion beam transport (invited)  

SciTech Connect (OSTI)

Depending on the specific type of ion source, the ion beam is extracted either from an electrode surface or from a plasma. There is always an interface between the (almost) space charge compensated ion source plasma, and the extraction region in which the full space charge is influencing the ion beam itself. After extraction, the ion beam is to be transported towards an accelerating structure in most cases. For lower intensities, this transport can be done without space charge compensation. However, if space charge is not negligible, the positive charge of the ion beam will attract electrons, which will compensate the space charge, at least partially. The final degree of Space Charge Compensation (SCC) will depend on different properties, like the ratio of generation rate of secondary particles and their loss rate, or the fact whether the ion beam is pulsed or continuous. In sections of the beam line, where the ion beam is drifting, a pure electrostatic plasma will develop, whereas in magnetic elements, these space charge compensating electrons become magnetized. The transport section will provide a series of different plasma conditions with different properties. Different measurement tools to investigate the degree of space charge compensation will be described, as well as computational methods for the simulation of ion beams with partial space charge compensation.

Spdtke, Peter, E-mail: p.spaedtke@gsi.de [GSI Helmholtzzentrum fr Schwerionenforschung GmbH (Germany)] [GSI Helmholtzzentrum fr Schwerionenforschung GmbH (Germany)

2014-02-15T23:59:59.000Z

134

Ion transport in sub-5-nm graphene nanopores  

SciTech Connect (OSTI)

Graphene nanopore is a promising device for single molecule sensing, including DNA bases, as its single atom thickness provides high spatial resolution. To attain high sensitivity, the size of the molecule should be comparable to the pore diameter. However, when the pore diameter approaches the size of the molecule, ion properties and dynamics may deviate from the bulk values and continuum analysis may not be accurate. In this paper, we investigate the static and dynamic properties of ions with and without an external voltage drop in sub-5-nm graphene nanopores using molecular dynamics simulations. Ion concentration in graphene nanopores sharply drops from the bulk concentration when the pore radius is smaller than 0.9nm. Ion mobility in the pore is also smaller than bulk ion mobility due to the layered liquid structure in the pore-axial direction. Our results show that a continuum analysis can be appropriate when the pore radius is larger than 0.9nm if pore conductivity is properly defined. Since many applications of graphene nanopores, such as DNA and protein sensing, involve ion transport, the results presented here will be useful not only in understanding the behavior of ion transport but also in designing bio-molecular sensors.

Suk, Myung E.; Aluru, N. R., E-mail: aluru@illinois.edu [Department of Mechanical Science and Engineering, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

2014-02-28T23:59:59.000Z

135

E-Print Network 3.0 - aluminium-induced ion transport Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Weak Shear... and Reversed Shear plasmas Investigation of energetic ion transport during AEs - Summary Table of Contents 12... keV, PNNB>4MW) energetic ion ... Source:...

136

Reduced Fast Ion Transport Model For The Tokamak Transport Code TRANSP  

SciTech Connect (OSTI)

Fast ion transport models presently implemented in the tokamak transport code TRANSP [R. J. Hawryluk, in Physics of Plasmas Close to Thermonuclear Conditions, CEC Brussels, 1 , 19 (1980)] are not capturing important aspects of the physics associated with resonant transport caused by instabilities such as Toroidal Alfv#19;en Eigenmodes (TAEs). This work describes the implementation of a fast ion transport model consistent with the basic mechanisms of resonant mode-particle interaction. The model is formulated in terms of a probability distribution function for the particle's steps in phase space, which is consistent with the MonteCarlo approach used in TRANSP. The proposed model is based on the analysis of fast ion response to TAE modes through the ORBIT code [R. B. White et al., Phys. Fluids 27 , 2455 (1984)], but it can be generalized to higher frequency modes (e.g. Compressional and Global Alfv#19;en Eigenmodes) and to other numerical codes or theories.

Podesta,, Mario; Gorelenkova, Marina; White, Roscoe

2014-02-28T23:59:59.000Z

137

Synthesis of nanomesh, thin film nanocomposite, nanocomposite membranes and synthesis of potassium ion selective membrane electrodes  

E-Print Network [OSTI]

Synthesis of nanomesh, thin film nanocomposite, nanocomposite membranes and synthesis of potassium and naofibers, which has potential use in protection of agricultural products from hailing. We developed

Singh, Jayant K.

138

Futile cycling at the plasma membrane: a hallmark of  

E-Print Network [OSTI]

. Transport systems catalyzing ion influx across the plasma membrane of root cells fall into two broadFutile cycling at the plasma membrane: a hallmark of low-affinity nutrient transport Dev T. Britto-affinity transport systems in the plasma membranes of root cells. In this Opinion article, we illustrate that for six

Britto, Dev T.

139

Ninth International Workshop on Plant Membrane Biology  

SciTech Connect (OSTI)

This report is a compilation of abstracts from papers which were discussed at a workshop on plant membrane biology. Topics include: plasma membrane ATP-ases; plant-environment interactions, membrane receptors; signal transduction; ion channel physiology; biophysics and molecular biology; vaculor H+ pumps; sugar carriers; membrane transport; and cellular structure and function.

Not Available

1993-12-31T23:59:59.000Z

140

Hybrid membrane/cryogenic separation of oxygen from air for use in the oxy-fuel process  

E-Print Network [OSTI]

and high temperature ion transport membranes. While polymeric membranes can produce oxygen enriched air of various concentrations, ion transport membranes can produce purities of close to 100%. Both membraHybrid membrane/cryogenic separation of oxygen from air for use in the oxy-fuel process Thomas

Struchtrup, Henning

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
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141

Water transport in fuel cell membranes measured by laser interferometry  

E-Print Network [OSTI]

(cont.) The coefficients of electro-osmotic drag were found to increase with the increasing water content, which indicates that the Grotthuss mechanism of proton transfer is not active in the membranes with low water ...

Kim, Jungik, 1973-

2009-01-01T23:59:59.000Z

142

Homogenization of the Poisson-Nernst-Planck Equations for Ion Transport in Charged Porous Media  

E-Print Network [OSTI]

Effective Poisson-Nernst-Planck (PNP) equations are derived for macroscopic ion transport in charged porous media under periodic fluid flow by an asymptotic multi-scale expansion with drift. The microscopic setting is a two-component periodic composite consisting of a dilute electrolyte continuum (described by standard PNP equations) and a continuous dielectric matrix, which is impermeable to the ions and carries a given surface charge. Four new features arise in the upscaled equations: (i) the effective ionic diffusivities and mobilities become tensors, related to the microstructure; (ii) the effective permittivity is also a tensor, depending on the electrolyte/matrix permittivity ratio and the ratio of the Debye screening length to the macroscopic length of the porous medium; (iii) the microscopic fluidic convection is replaced by a diffusion-dispersion correction in the effective diffusion tensor; and (iv) the surface charge per volume appears as a continuous "background charge density", as in classical membrane models. The coefficient tensors in the upscaled PNP equations can be calculated from periodic reference cell problems. For an insulating solid matrix, all gradients are corrected by the same tensor, and the Einstein relation holds at the macroscopic scale, which is not generally the case for a polarizable matrix, unless the permittivity and electric field are suitably defined. In the limit of thin double layers, Poisson's equation is replaced by macroscopic electroneutrality (balancing ionic and surface charges). The general form of the macroscopic PNP equations may also hold for concentrated solution theories, based on the local-density and mean-field approximations. These results have broad applicability to ion transport in porous electrodes, separators, membranes, ion-exchange resins, soils, porous rocks, and biological tissues.

Markus Schmuck; Martin Z. Bazant

2014-07-14T23:59:59.000Z

143

ADVANCED HYDROGEN TRANSPORT MEMBRANES FOR VISION 21 FOSSIL FUEL PLANTS  

SciTech Connect (OSTI)

Eltron Research Inc., and team members, are developing an environmentally benign, inexpensive, and efficient method for separating hydrogen from gas mixtures produced during industrial processes, such as coal gasification. This project was motivated by the National Energy Technology Laboratory (NETL) Vision 21 initiative which seeks to economically eliminate environmental concerns associated with the use of fossil fuels. This objective is being pursued using dense membranes based in part on Eltron-patented ceramic materials with a demonstrated ability for proton and electron conduction. The technical goals are being addressed by modifying single-phase and composite membrane composition and microstructure to maximize proton and electron conductivity without loss of material stability. Ultimately, these materials must enable hydrogen separation at practical rates under ambient and high-pressure conditions, without deactivation in the presence of feedstream components such as carbon dioxide, water, and sulfur. During this quarter, it was demonstrated that increasing the transition metal loading in a model perovskite composition resulted in an increase in hydrogen flux. Improved flux corresponded to the emergence of additional phases in the ceramic membrane, and highest flux was achieved for a composite consisting of pseudo-cubic and rhombohedral perovskite phases. A 0.9-mm thick membrane of this material generated a hydrogen flux in excess of 0.1 mL/min/cm{sup 2}, which was approximately 35 times greater than analogs with lower transition metal levels. The dopant level and crystal structure also correlated with membrane density and coefficient of thermal expansion, but did not appear to affect grain size or shape. Additionally, preliminary ceramic-metal (cermet) composite membranes demonstrated a 10-fold increase in flux relative to analogous membranes composed of only the ceramic component. The hydrogen flux for these cermet samples corresponded to a conductivity of {approx} 10{sup -3} S/cm, which was consistent with the predicted proton conductivity of the ceramic phase. Increasing the sweep gas flow rate in test reactors was found to significantly increase hydrogen flux, as well as apparent material conductivity for all samples tested. Adding humidity to the feed gas stream produced a small increase in hydrogen flux. However, the catalyst on ceramic membrane surfaces did not affect flux, which suggested that the process was membrane-diffusion limited. Representative samples and fabrication processes were evaluated on the basis of manufacturing practicality. it was determined that optimum membrane densification occurs over a very narrow temperature range for the subject ceramics. Additionally, calcination temperatures currently employed result in powders that are difficult mill and screen. These issues must be addressed to improve large-scale fabricability.

Shane E. Roark; Tony F. Sammells; Adam E. Calihman; Lyrik Y. Pitzman; Pamela M. Van Calcar; Richard A. Mackay; Tom F. Barton; Sara L. Rolfe; Richard N. Kleiner; James E. Stephan; Tim R. Armstrong; Mike J. Holmes; Aaron L. Wagner

2001-04-30T23:59:59.000Z

144

Feed gas contaminant removal in ion transport membrane systems  

DOE Patents [OSTI]

Method for gas purification comprising (a) obtaining a feed gas stream containing one or more contaminants selected from the group consisting of volatile metal oxy-hydroxides, volatile metal oxides, and volatile silicon hydroxide; (b) contacting the feed gas stream with a reactive solid material in a guard bed and reacting at least a portion of the contaminants with the reactive solid material to form a solid reaction product in the guard bed; and (c) withdrawing from the guard bed a purified gas stream.

Carolan, Michael Francis (Allentown, PA); Miller, Christopher Francis (Macungie, PA)

2008-09-16T23:59:59.000Z

145

Ion Transport in Nanostructured Block Copolymer/Ionic Liquid Membranes  

E-Print Network [OSTI]

14-18 fuel cells, 19-26 dye-sensitized solar cells, 27, 28batteries or dye-sensitized solar cells. 57, 58 PVdF-co-PHFP

Hoarfrost, Megan Lane

2012-01-01T23:59:59.000Z

146

Stochastic Dynamics of Electrical Membrane with Voltage-Dependent Ion Channel Fluctuations  

E-Print Network [OSTI]

Brownian ratchet like stochastic theory for the electrochemical membrane system of Hodgkin-Huxley (HH) is developed. The system is characterized by a continuous variable $Q_m(t)$, representing mobile membrane charge density, and a discrete variable $K_t$ representing ion channel conformational dynamics. A Nernst-Planck-Nyquist-Johnson type equilibrium is obtained when multiple conducting ions have a common reversal potential. Detailed balance yields a previously unknown relation between the channel switching rates and membrane capacitance, bypassing Eyring-type explicit treatment of gating charge kinetics. From a molecular structural standpoint, membrane charge $Q_m$ is a more natural dynamic variable than potential $V_m$; our formalism treats $Q_m$-dependent conformational transition rates $\\lambda_{ij}$ as intrinsic parameters. Therefore in principle, $\\lambda_{ij}$ vs. $V_m$ is experimental protocol dependent,e.g., different from voltage or charge clamping measurements. For constant membrane capacitance per unit area $C_m$ and neglecting membrane potential induced by gating charges, $V_m=Q_m/C_m$, and HH's formalism is recovered. The presence of two types of ions, with different channels and reversal potentials, gives rise to a nonequilibrium steady state with positive entropy production $e_p$. For rapidly fluctuating channels, an expression for $e_p$ is obtained.

Hong Qian; Xue-Juan Zhang; Min Qian

2014-04-06T23:59:59.000Z

147

Shear flow effects on ion thermal transport in tokamaks  

SciTech Connect (OSTI)

From various laboratory and numerical experiments, there is clear evidence that under certain conditions the presence of sheared flows in a tokamak plasma can significantly reduce the ion thermal transport. In the presence of plasma fluctuations driven by the ion temperature gradient, the flows of energy and momentum parallel and perpendicular to the magnetic field are coupled with each other. This coupling manifests itself as significant off-diagonal coupling coefficients that give rise to new terms for anomalous transport. The authors derive from the gyrokinetic equation a set of velocity moment equations that describe the interaction among plasma turbulent fluctuations, the temperature gradient, the toroidal velocity shear, and the poloidal flow in a tokamak plasma. Four coupled equations for the amplitudes of the state variables radially extended over the transport region by toroidicity induced coupling are derived. The equations show bifurcations from the low confinement mode without sheared flows to high confinement mode with substantially reduced transport due to strong shear flows. Also discussed is the reduced version with three state variables. In the presence of sheared flows, the radially extended coupled toroidal modes driven by the ion temperature gradient disintegrate into smaller, less elongated vortices. Such a transition to smaller spatial correlation lengths changes the transport from Bohm-like to gyrobohm-like. The properties of these equations are analyzed. The conditions for the improved confined regime are obtained as a function of the momentum-energy deposition rates and profiles. The appearance of a transport barrier is a consequence of the present theory.

Tajima, T.; Horton, W.; Dong, J.Q. [Univ. of Texas, Austin, TX (United States). Institute for Fusion Studies; Kishimoto, Y. [JAERI (Japan). Naka Fusion Research

1995-03-01T23:59:59.000Z

148

Exceptional ion rejection ability of directional solvent for non-membrane desalination  

SciTech Connect (OSTI)

The recently demonstrated directional solvent extraction (DSE) is promising for very low temperature, membrane-free water desalination. In this paper, we combine atomistic simulations and experimental validation to demonstrate that the currently used directional solvent, decanoic acid, can reject all major salt ions in seawater, with very high rejection rates. The salinities of the DSE recovered water show that ion rejection rates are ?98%99%similar to those of the best reverse osmosis membranes. Our test also shows that the DSE process can desalt seawater to produce fresh water that meets drinking water standards.

Rish, Daniel [Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Department of Civil Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Luo, Shirui; Kurtz, Brien [Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Luo, Tengfei, E-mail: tluo@nd.edu [Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Center for Sustainable Energy at Notre Dame, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

2014-01-13T23:59:59.000Z

149

Stopping and Baryon Transport in Heavy Ion Reactions  

E-Print Network [OSTI]

In this report I will give an experimental overview on nuclear stopping in hadron collisions, and relate observations to understanding of baryon transport. Baryon number transport is not only evidenced via net-proton distributions but also by the enhancement of strange baryons near mid-rapidity. Although the focus is on high-energy data obtained from pp and heavy ions from RHIC, relevant data from SPS and ISR will be considered. A discussion how the available data at higher energy relates and gives information on baryon junction, quark-diquark breaking will be made.

F. Videbaek

2005-05-10T23:59:59.000Z

150

Development of an spFRET method to measure structure changes in ion exchange proteins  

E-Print Network [OSTI]

transporter, major facilitator superfamily, membrane transport, membrane transporter, OxlT, single molecule, spFRET, transport protein. Tightly coupled ion exchangers, such as the AE anion exchange systems only take place at an appreciable rate if a suitable substrate ion is bound to the transport site

Novotny, Lukas

151

A Complete Transport Validated Model on a Zeolite Membrane for Carbon Dioxide Permeance and Capture  

E-Print Network [OSTI]

The CO2 emissions from major industries cause serious global environment problems and their mitigation is urgently needed. The use of zeolite membranes is a very efficient way in order to capture CO2 from some flue gases. The dominant transport mechanism at low temperature andor high pressure is the diffusion through the membrane. This procedure can be divided in three steps: Adsorption of the molecules of the species in the surface of the membrane, then a driving force gives a path where the species follow inside the membrane and finally the species desorbed from the surface of the membrane. The current work is aimed at developing a simulation model for the CO2 transport through a zeolite membrane and estimate the diffusion phenomenon through a very thin membrane of 150 nm in a Wicke-Kallenbach cell. The cell is cylindrical in shape with diameter of 19 mm and consists of a retentate gas chamber, a permeate gas chamber which are separated by a cylindrical zeolite membrane. This apparatus have been modeled wit...

Gkanas, Evangelos I; Stubos, Athanasios K; Makridis, Sofoklis S

2013-01-01T23:59:59.000Z

152

ADVANCED HYDROGEN TRANSPORT MEMBRANES FOR VISION 21 FOSSIL FUEL PLANTS  

SciTech Connect (OSTI)

Eltron Research Inc., and team members CoorsTek, Sued Chemie, and Argonne National Laboratory are developing an environmentally benign, inexpensive, and efficient method for separating hydrogen from gas mixtures produced during industrial processes, such as coal gasification. This project was motivated by the National Energy Technology Laboratory (NETL) Vision 21 initiative which seeks to economically eliminate environmental concerns associated with the use of fossil fuels. This objective is being pursued using dense membranes based in part on Eltron-patented ceramic materials with a demonstrated ability for proton and electron conduction. The technical goals are being addressed by modifying composite membrane composition and microstructure to maximize hydrogen permeation without loss of material stability. Ultimately, these materials must enable hydrogen separation at practical rates under ambient and high-pressure conditions, without deactivation in the presence of feedstream components such as carbon dioxide, water, and sulfur. During this quarter, a composite metal membrane based on an inexpensive hydrogen permeable metal achieved permeation rates in excess of 25 mL/min/cm{sup 2}. Preliminary attempts to incorporate this metal into a cermet were successful, and a thick cermet membrane (0.83 mm) with 40 vol.% metal phase achieved a permeation rate of nearly 0.4 mL/min/cm{sup 2}. Increasing the metal phase content and decreasing membrane thickness should significantly increase permeation, while maintaining the benefits derived from cermets. Two-phase ceramic/ceramic composite membranes had low hydrogen permeability, likely due to interdiffusion of constituents between the phases. However, these materials did demonstrate high resistance to corrosion, and might be good candidates for other composite membranes. Temperature-programmed reduction measurements indicated that model cermet materials absorbed 2.5 times as much hydrogen than the pure ceramic analogs. This characteristic, in addition to higher electron conductivity, likely explains the relatively high permeation for these cermets. Incorporation of catalysts with ceramics and cermets increased hydrogen uptake by 800 to more than 900%. Finally, new high-pressure seals were developed for cermet membranes that maintained a pressure differential of 250 psi. This result indicated that the approach for high-pressure seal development could be adapted for a range of compositions. Other items discussed in this report include mechanical testing, new proton conducting ceramics, supported thin films, and alkane to olefin conversion.

Shane E. Roark; Anthony F. Sammells; Richard A. Mackay; Lyrik Y. Pitzman; Thomas A. Zirbel; Stewart R. Schesnack; Thomas F. Barton; Sara L. Rolfe; U. (Balu) Balachandran; Richard N. Kleiner; James E. Stephan; Frank E. Anderson; Aaron L. Wagner; Jon P. Wagner

2003-01-30T23:59:59.000Z

153

Fast ion transport induced by saturated infernal mode  

SciTech Connect (OSTI)

Tokamak discharges with extended weak-shear central core are known to suffer from infernal modes when the core safety factor approaches the mode ratio. These modes can cause an outward convection of the well-passing energetic ions deposited in the core by fusion reactions and/or neutral beam injection. Convection mechanism consists in collisional slowing down of energetic ions trapped in the Doppler-precession resonance with a finite-amplitude infernal mode. Convection velocity can reach a few m/s in modern spherical tori. Possible relation of this transport with the enhanced fast ion losses in the presence of long lived modes in the MAST tokamak [I. T. Chapman et al., Nucl. Fusion 50, 045007 (2010)] is discussed.

Marchenko, V. S., E-mail: march@kinr.kiev.ua [Institute for Nuclear Research, Kyiv (Ukraine)

2014-05-15T23:59:59.000Z

154

Validation of Heavy Ion Transport Capabilities in PHITS  

SciTech Connect (OSTI)

The performance of the Monte Carlo code system PHITS is validated for heavy ion transport capabilities by performing simulations and comparing results against experimental data from heavy ion reactions of benchmark quality. These data are from measurements of secondary neutron production cross sections in reactions of Xe at 400 MeV/u with lithium and lead targets, measurements of neutrons outside of thick concrete and iron shields, and measurements of isotope yields produced in the fragmentation of a 140 MeV/u 48Ca beam on a beryllium target and on a tantalum target. A practical example that tests magnetic field capabilities is shown for a simulated 48Ca beam at 500 MeV/u striking a lithium target to produce the rare isotope 44Si, with ion transport through a fragmentation-reaction magnetic pre-separator. The results of this study show that PHITS performs reliably for the simulation of radiation fields that is necessary for designing safe, reliable and cost effective future high-powered heavy-ion accelerators in rare isotope beam facilities.

Ronningen, Reginald M. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States)

2007-03-19T23:59:59.000Z

155

Test particle study of ion transport in drift type turbulence  

SciTech Connect (OSTI)

Ion transport regimes in drift type turbulence are determined in the frame of a realistic model for the turbulence spectrum based on numerical simulations. The model includes the drift of the potential with the effective diamagnetic velocity, turbulence anisotropy, and dominant waves. The effects of the zonal flow modes are also analyzed. A semi-analytical method that is able to describe trajectory stochastic trapping or eddying is used for obtaining the transport coefficients as function of the parameters of the turbulence. Analytical approximations of the transport coefficients are derived from the results. They show the transition from Bohm to gyro-Bohm scaling as plasma size increases in very good agreement with the numerical simulations.

Vlad, M.; Spineanu, F. [National Institute of Laser, Plasma and Radiation Physics, Association EURATOM-MEdC, Atomistilor 409, 077125 Magurele, Bucharest (Romania)] [National Institute of Laser, Plasma and Radiation Physics, Association EURATOM-MEdC, Atomistilor 409, 077125 Magurele, Bucharest (Romania)

2013-12-15T23:59:59.000Z

156

Electric transport and oxygen permeation properties of lanthanum cobaltite membranes synthesized by different methods  

SciTech Connect (OSTI)

Dense perovskite-structured membranes with desired composition of La{sub 0.8}Sr{sub 0.2}Co{sub 0.6}Fe{sub 0.4}O{sub 3{minus}{delta}} (LSCF) were prepared from powders produced by four different methods. LSCF powders prepared by citrate, solid-state, and spray-pyrolysis methods had compositions close to the desired stoichiometry with a slight difference in cobalt concentration, whereas coprecipitated powders had a large strontium deficiency. The membrane composition was a determining factor that affected the electronic conductivity and therefore oxygen permeability. The membrane with a large strontium deficiency had much lower electronic conductivity and oxygen permeability (ionic conductivity) than the other three membranes with compositions close to the desired stoichiometry. The electronic conductivity of membranes prepared from citrate, solid-state, and spray-pyrolysis methods increases with the cobalt concentration of the membrane. For the three membranes with similar composition, the activation energy of oxygen flux decreases with increasing grain size. Oxygen pressure dependency of oxygen vacancy concentration is also influenced by the membrane microstructure and composition. LSCF membranes with same composition and similar microstructure should have similar electric and oxygen transport properties.

Qi, X.; Lin, Y.S.; Swartz, S.L.

2000-03-01T23:59:59.000Z

157

A Novel Cl Inward-Rectifying Current in the Plasma Membrane of the Calcifying Marine Phytoplankton  

E-Print Network [OSTI]

as much as 40% of annual global carbon assimilation. Ion and nutrient transport across the plasma membrane revealed a dominant anion conductance in response to membrane hyperpolarization. Ion substitution showed conductances play an essential role in membrane voltage regulation that relates to the unique transport

Taylor, Alison

158

Membrane-Extraction Ion Mobility Spectrometry for In-Situ Detection of Chlorinated Hydrocarbons in Water  

SciTech Connect (OSTI)

Membrane-extraction ion mobility spectrometry (ME-IMS) has been developed for in-situ sampling and analysis of trace chlorinated hydrocarbons in water in a single procedure. The sampling is configured so that aqueous contaminants permeate through a spiral hollow polydimethylsiloxane (PDMS) membrane and are carried away by a vapor flow through the membrane tube. The extracted analyte flows into an atmospheric pressure chemical ionization (APCI) chamber and is analyzed in a home-made IMS analyzer. PDMS membrane is found to effectively extract chlorinated hydrocarbon solvents from liquid phase to vapor. The specialized IMS analyzer has been found to have resolutions of R=33 and 41, respectively, for negative- and positive-modes and is capable of detecting aqueous tetrachloroethylene (PCE) and trichloroethylene (TCE) as low as 80 g/L and 74 g/L in negative ion mode, respectively. The time-dependent characteristics of sampling and detection of TCE are both experimentally and theoretically studied for various concentrations, membrane lengths, and flow rates. These characteristics demonstrate that membrane-extraction IMS is feasible for the continuous monitoring of chlorinated hydrocarbons in water.

Du, Yongzhai [ORNL; Zhang, Wei [ORNL; Whitten, William B [ORNL; Li, Haiyang [ORNL; Watson, David B [ORNL; Xu, Jun [ORNL

2010-01-01T23:59:59.000Z

159

ADVANCED HYDROGEN TRANSPORT MEMBRANES FOR VISION 21 FOSSIL FUEL PLANTS  

SciTech Connect (OSTI)

Eltron Research Inc., and team members CoorsTek, McDermott Technology, inc., Sued Chemie, Argonne National Laboratory, and Oak Ridge National Laboratory are developing an environmentally benign, inexpensive, and efficient method for separating hydrogen from gas mixtures produced during industrial processes, such as coal gasification. This project was motivated by the National Energy Technology Laboratory (NETL) Vision 21 initiative which seeks to economically eliminate environmental concerns associated with the use of fossil fuels. This objective is being pursued using dense membranes based in part on Eltron-patented ceramic materials with a demonstrated ability for proton and electron conduction. The technical goals are being addressed by modifying single-phase and composite membrane composition and microstructure to maximize proton and electron conductivity without loss of material stability. Ultimately, these materials must enable hydrogen separation at practical rates under ambient and high-pressure conditions, without deactivation in the presence of feedstream components such as carbon dioxide, water, and sulfur.

Shane E. Roark; Anthony F. Sammells; Richard A. Mackay; Lyrik Y. Pitzman; Thomas A. Zirbel; Thomas F. Barton; Sara L. Rolfe; U. (Balu) Balachandran; Richard N. Kleiner; James E. Stephan; Frank E. Anderson; George Farthing; Dan Rowley; Tim R. Armstrong; R.D. Carneim; P.F. Becher; C-H. Hsueh; Aaron L. Wagner; Jon P. Wagner

2002-04-30T23:59:59.000Z

160

Mitochondrial potassium transport: the K+ Keith D. Garlid*, Petr Paucek  

E-Print Network [OSTI]

; Ion channel gating; Membrane transport; Volume regulation 1. Introduction The inner membrane. This means that ion traffic across the inner membrane will be very high. Moreover, the gradients driving saltReview Mitochondrial potassium transport: the K+ cycle Keith D. Garlid*, Petr Paucek Department

Garlid, Keith

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

ITM Syngas and ITM H2: Engineering Development of Ceramic Membrane Reactor Systems for  

E-Print Network [OSTI]

(U.S. DOE) and other members of the ITM Syngas/ITM H2 Team, is developing Ion Transport Membrane (ITM of the ITM membrane to oxygen ions, which diffuse through the membrane under a chemical potential gradientITM Syngas and ITM H2: Engineering Development of Ceramic Membrane Reactor Systems for Converting

162

Chaotic behavior of ion exchange phenomena in polymer gel electrolytes through irradiated polymeric membrane  

E-Print Network [OSTI]

A desktop experiment has been done to show the nonlinearity in the I-V characteristics of an ion conducting electrochemical micro-system. Its chaotic dynamics is being reported for the first time which has been captured by an electronic circuit. Polyvinylidene fluoride-co-hexafluoropropene (PVdF-HFP) gel electrolyte comprising of a combination of plasticizers (ethylene carbonate and propylene carbonate) and salts have been prepared to study the exchange of ions through porous poly ethylene terephthalate (PET) membranes. The nonlinearity of this system is due to the ion exchange of the polymer gel electrolytes (PGEs) through a porous membrane. The different regimes of spiking and non-spiking chaotic motions are being presented. The possible applications are highlighted.

Sangeeta Rawat; Barnamala Saha; Awadhesh Prasad; Amita Chandra

2012-04-18T23:59:59.000Z

163

Structures for Three Membrane Transport Proteins Yield Functional Insights  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassiveSubmittedStatus TomAbout » Staff125,849|Structures for Three Membrane

164

Transport Phenomena in Polymer Electrolyte Membranes I. Modeling Framework  

E-Print Network [OSTI]

and optimization of fuel cells in a design and development environment. Kreuer et al.19 recently presented of ongoing efforts to develop more comprehensive compu- tational fuel cell model14-18 that allow analysis of the fundamental transport mechanisms. In the context of multidimensional fuel cell modeling, practical

Struchtrup, Henning

165

Bioenergetics and mechanical actuation analysis with membrane transport experiments for use in biomimetic  

E-Print Network [OSTI]

Bioenergetics and mechanical actuation analysis with membrane transport experiments for use considers the mechanics and bioenergetics of a prototype nastic structure system consisting of an array by the hydrolysis of adenosine triphosphate. After reviewing the biochemistry and bioenergetics of the active

Giurgiutiu, Victor

166

Transport Properties and Performance of Polymer Electrolyte Membranes for the Hybrid Sulfur Electrolyzer  

E-Print Network [OSTI]

not consume fossil fuels or pro- duce CO2 while producing highly pure hydrogen.1-10 Gaseous SO2 fedTransport Properties and Performance of Polymer Electrolyte Membranes for the Hybrid Sulfur and Biological Systems Department, Albuquerque, New Mexico 87123, USA c Department of Materials Science

Weidner, John W.

167

The Arabidopsis Chaperone J3 Regulates the Plasma Membrane H+-ATPase through Interaction with the  

E-Print Network [OSTI]

membrane H+-ATPase (PM H+-ATPase) plays an important role in the regulation of ion and metabolite transport inactivation of the PKS5 kinase. INTRODUCTION In both plants and fungi, transport across the plasma membrane constitutes a driving force for the transport of solutes and metab- olites across the plasma membrane

Deng, Xing-Wang

168

Supporting Information for: Salt concentration differences alter membrane  

E-Print Network [OSTI]

). The membrane area available for ion transport was 11.4 cm2 . Platinum mesh electrodes that spanned the crossS1 Supporting Information for: Salt concentration differences alter membrane resistance in reverse-814-867-1847 #12;S2 Membrane resistance measurement Without a concentration difference Membrane resistance

169

Simulation of Membrane and Cell Culture Permeability and Transport  

E-Print Network [OSTI]

for neutral and ionized species partitioning into the membrane - only non-ionized species. Donor bulk (D) Acceptor bulk (A) D w h w D w h w k i c N k o c N ?? = ? = ?+?? ? + ? + = == i 1p pKa-pHpj 1r pH1)r(jpKa Ux N x p 1s a s j rs b s 10101 1 cc c..., Kansas, 2006 Pgp expression in human SI Mouly, S., Paine, M.F. PharmRes-20(10):1595-1598 (2003) GPEN, Kansas, 2006 Talinolol Non-linear Dose Dependence Talinolol Dose Dependence de Mey et al. J. Cardio. Pharmacol. 26(6):879 (1995) 0 200 400 600 800 1000...

Bolger, Michael

2006-10-26T23:59:59.000Z

170

E-Print Network 3.0 - active ion transport Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

gases,2-6 or in the active... , oscillations in the electric field are damped in the bulk plasma and ion transport is governed by ion drift... , these oscillations are damped...

171

Computational study of the transport mechanisms of molecules and ions in solid materials  

E-Print Network [OSTI]

electrolytes is a key element in the development of the solid lithium ion batteries. One promising material is dilithium phthalocyanine (Li2Pc), which upon self-assembly may form conducting channels for fast ion transport. Computational chemistry is employed...

Zhang, Yingchun

2009-06-02T23:59:59.000Z

172

Qualitative determination of H2S crossover rates in nation membranes using ion-probe techniques  

SciTech Connect (OSTI)

Polymer electrolyte membrane fuel cells are sensitive to impurities that may be present in either the oxidizer or fuel. H2S, even at the ppb level, will have a dramatic and adverse affect on fuel cell performance. The H2S permeability through dry and humidified Nafion PEMFC membranes was studied using ion probe techniques. A sulfide anti-oxidant buffer solution was used to trap and concentrate trace quantities of H2S that permeated through 50 cm2samples of Nafion 117 and 212 membranes using a partial pressure difference up to I030ppm at room temperature. Experiments were conducted for up to 24 hours in order to achieve sulfide ion concentrations high enough to be precisely determined by subsequent titration with Pb(N03)2. The rate of H2S crossover for dry 117 and 212 were identical at 1.2e-7 g/min. Humidification increased the crossover rate to 5.ge-7 glmin and 1.8e-6 glmin for 117 and 212 respectively. Although the data collected in this work show that the rate of H2S crossover increases with water content and reduced membrane thickness, an accurate determination of permeation constants from this work was not possible because the H2S partial pressure was not constant throughout the experiment.

Brosha, Eric L [Los Alamos National Laboratory; Rockward, Tommy [Los Alamos National Laboratory; Uribe, Francisco A [Los Alamos National Laboratory; Garzon, Fernando H [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

173

Zero Emission Power Plants Using Solid Oxide Fuel Cells and Oxygen Transport Membranes  

SciTech Connect (OSTI)

Siemens Westinghouse Power Corp. (SWPC) is engaged in the development of Solid Oxide Fuel Cell stationary power systems. SWPC has combined DOE Developmental funds with commercial customer funding to establish a record of successful SOFC field demonstration power systems of increasing size. SWPC will soon deploy the first unit of a newly developed 250 kWe Combined Heat Power System. It will generate electrical power at greater than 45% electrical efficiency. The SWPC SOFC power systems are equipped to operate on lower number hydrocarbon fuels such as pipeline natural gas, which is desulfurized within the SOFC power system. Because the system operates with a relatively high electrical efficiency, the CO2 emissions, {approx}1.0 lb CO2/ kW-hr, are low. Within the SOFC module the desulfurized fuel is utilized electrochemically and oxidized below the temperature for NOx generation. Therefore the NOx and SOx emissions for the SOFC power generation system are near negligible. The byproducts of the power generation from hydrocarbon fuels that are released into the environment are CO2 and water vapor. This forward looking DOE sponsored Vision 21 program is supporting the development of methods to capture and sequester the CO2, resulting in a Zero Emission power generation system. To accomplish this, SWPC is developing a SOFC module design, to be demonstrated in operating hardware, that will maintain separation of the fuel cell anode gas, consisting of H2, CO, H2O and CO2, from the vitiated air. That anode gas, the depleted fuel stream, containing less than 18% (H2 + CO), will be directed to an Oxygen Transport Membrane (OTM) Afterburner that is being developed by Praxair, Inc.. The OTM is supplied air and the depleted fuel. The OTM will selectively transport oxygen across the membrane to oxidize the remaining H2 and CO. The water vapor is then condensed from the totally 1.5.DOC oxidized fuel stream exiting the afterburner, leaving only the CO2 in gaseous form. That CO2 can then be compressed and sequestered, resulting in a Zero Emission power generation system operating on hydrocarbon fuel that adds only water vapor to the environment. Praxair has been developing oxygen separation systems based on dense walled, mixed electronic, oxygen ion conducting ceramics for a number of years. The oxygen separation membranes find applications in syngas production, high purity oxygen production and gas purification. In the SOFC afterburner application the chemical potential difference between the high temperature SOFC depleted fuel gas and the supplied air provides the driving force for oxygen transport. This permeated oxygen subsequently combusts the residual fuel in the SOFC exhaust. A number of experiments have been carried out in which simulated SOFC depleted fuel gas compositions and air have been supplied to either side of single OTM tubes in laboratory-scale reactors. The ceramic tubes are sealed into high temperature metallic housings which precludes mixing of the simulated SOFC depleted fuel and air streams. In early tests, although complete oxidation of the residual CO and H2 in the simulated SOFC depleted fuel was achieved, membrane performance degraded over time. The source of degradation was found to be contaminants in the simulated SOFC depleted fuel stream. Following removal of the contaminants, stable membrane performance has subsequently been demonstrated. In an ongoing test, the dried afterburner exhaust composition has been found to be stable at 99.2% CO2, 0.4% N2 and 0.6%O2 after 350 hours online. Discussion of these results is presented. A test of a longer, commercial demonstration size tube was performed in the SWPC test facility. A similar contamination of the simulated SOFC depleted fuel stream occurred and the performance degraded over time. A second test is being prepared. Siemens Westinghouse and Praxair are collaborating on the preliminary design of an OTM equipped Afterburner demonstration unit. The intent is to test the afterburner in conjunction with a reduced size SOFC test module that has the anode gas separati

Shockling, Larry A.; Huang, Keqin; Gilboy, Thomas E. (Siemens Westinghouse Power Corporation); Christie, G. Maxwell; Raybold, Troy M. (Praxair, Inc.)

2001-11-06T23:59:59.000Z

174

Catalyzed CO.sub.2-transport membrane on high surface area inorganic support  

DOE Patents [OSTI]

Disclosed are membranes and methods for making the same, which membranes provide improved permeability, stability, and cost-effective manufacturability, for separating CO.sub.2 from gas streams such as flue gas streams. High CO.sub.2 permeation flux is achieved by immobilizing an ultra-thin, optionally catalyzed fluid layer onto a meso-porous modification layer on a thin, porous inorganic substrate such as a porous metallic substrate. The CO.sub.2-selective liquid fluid blocks non-selective pores, and allows for selective absorption of CO.sub.2 from gas mixtures such as flue gas mixtures and subsequent transport to the permeation side of the membrane. Carbon dioxide permeance levels are in the order of 1.0.times.10.sup.-6 mol/(m.sup.2sPa) or better. Methods for making such membranes allow commercial scale membrane manufacturing at highly cost-effective rates when compared to conventional commercial-scale CO.sub.2 separation processes and equipment for the same and such membranes are operable on an industrial use scale.

Liu, Wei

2014-05-06T23:59:59.000Z

175

Effective zero-thickness model for a conductive membrane driven by an electric field Falko Ziebert,1  

E-Print Network [OSTI]

membrane models is that they do not describe electrostatic effects associated with ion transport in details cells. A membrane can be driven out of equilibrium in many ways, for instance by ion concentration. The generation of ion con- centration gradients by internal means is controlled in bio- logical cells by membrane

Bazant, Martin Z.

176

Solenoidal Fields for Ion Beam Transport and Focusing  

SciTech Connect (OSTI)

In this report we calculate time-independent fields of solenoidal magnets that are suitable for ion beam transport and focusing. There are many excellent Electricity and Magnetism textbooks that present the formalism for magnetic field calculations and apply it to simple geometries [1-1], but they do not include enough relevant detail to be used for designing a charged particle transport system. This requires accurate estimates of fringe field aberrations, misaligned and tilted fields, peak fields in wire coils and iron, external fields, and more. Specialized books on magnet design, technology, and numerical computations [1-2] provide such information, and some of that is presented here. The AIP Conference Proceedings of the US Particle Accelerator Schools [1-3] contain extensive discussions of design and technology of magnets for ion beams - except for solenoids. This lack may be due to the fact that solenoids have been used primarily to transport and focus particles of relatively low momenta, e.g. electrons of less than 50 MeV and protons or H- of less than 1.0 MeV, although this situation may be changing with the commercial availability of superconducting solenoids with up to 20T bore field [1-4]. Internal reports from federal laboratories and industry treat solenoid design in detail for specific applications. The present report is intended to be a resource for the design of ion beam drivers for Inertial Fusion Energy [1-5] and Warm Dense Matter experiments [1-6], although it should also be useful for a broader range of applications. The field produced by specified currents and material magnetization can always be evaluated by solving Maxwell's equations numerically, but it is also desirable to have reasonably accurate, simple formulas for conceptual system design and fast-running beam dynamics codes, as well as for general understanding. Most of this report is devoted to such formulas, but an introduction to the Tosca{copyright} code [1-7] and some numerical results obtained with it are also presented. Details of design, fabrication, installation, and operation of magnet systems are not included; here we are concerned with calculations that precede or supplement detailed design. Mathematical derivations are presented with only a moderate number of steps. While there is no claim of originality, except for various numerical approximations and a conceptual induction module design in section 20, many of the results and discussions are not readily available elsewhere. Our primary topic is axisymmetric solenoidal systems with no magnetic materials. These simplifying features allow useful analytical calculations, which occupy sections 2-13. Deviations from axisymmetry are considered in sections 14, 15, 21, 22, and 23 and the effects of magnetic materials are treated in sections 16-20. Since magnetic aberrations are mixed with geometric aberrations in computing ion orbits, section 22 on the ion equations of motion in an arbitrary field is included.

Lee, Edward P.; Leitner, Matthaeus

2007-11-01T23:59:59.000Z

177

Molecular modeling of the morphology and transport properties of two direct methanol fuel cell membranes: phenylated sulfonated poly(ether ether ketone ketone) versus Nafion  

SciTech Connect (OSTI)

We have used molecular dynamics simulations to examine membrane morphology and the transport of water, methanol and hydronium in phenylated sulfonated poly ether ether ketone ketone (Ph-SPEEKK) and Nafion membranes at 360 K for a range of hydration levels. At comparable hydration levels, the pore diameter is smaller, the sulfonate groups are more closely packed, the hydronium ions are more strongly bound to sulfonate groups, and the diffusion of water and hydronium is slower in Ph-SPEEKK relative to the corresponding properties in Nafion. The aromatic carbon backbone of Ph-SPEEKK is less hydrophobic than the fluorocarbon backbone of Nafion. Water network percolation occurs at a hydration level ({lambda}) of {approx}8 H{sub 2}O/SO{sub 3}{sup -}. At {lambda} = 20, water, methanol and hydronium diffusion coefficients were 1.4 x 10{sup -5}, 0.6 x 10{sup -5} and 0.2 x 10{sup -5} cm{sup 2}/s, respectively. The pore network in Ph-SPEEKK evolves dynamically and develops wide pores for {lambda} > 20, which leads to a jump in methanol crossover and ion transport. This study demonstrates the potential of aromatic membranes as low-cost challengers to Nafion for direct methanol fuel cell applications and the need to develop innovative strategies to combat methanol crossover at high hydration levels.

Devanathan, Ramaswami; Idupulapati, Nagesh B.; Dupuis, Michel

2012-08-14T23:59:59.000Z

178

Transport Membrane Condenser for Water and Energy Recovery from Power Plant Flue Gas  

SciTech Connect (OSTI)

The new waste heat and water recovery technology based on a nanoporous ceramic membrane vapor separation mechanism has been developed for power plant flue gas application. The recovered water vapor and its latent heat from the flue gas can increase the power plant boiler efficiency and reduce water consumption. This report describes the development of the Transport Membrane Condenser (TMC) technology in details for power plant flue gas application. The two-stage TMC design can achieve maximum heat and water recovery based on practical power plant flue gas and cooling water stream conditions. And the report includes: Two-stage TMC water and heat recovery system design based on potential host power plant coal fired flue gas conditions; Membrane performance optimization process based on the flue gas conditions, heat sink conditions, and water and heat transport rate requirement; Pilot-Scale Unit design, fabrication and performance validation test results. Laboratory test results showed the TMC system can exact significant amount of vapor and heat from the flue gases. The recovered water has been tested and proved of good quality, and the impact of SO{sub 2} in the flue gas on the membrane has been evaluated. The TMC pilot-scale system has been field tested with a slip stream of flue gas in a power plant to prove its long term real world operation performance. A TMC scale-up design approach has been investigated and an economic analysis of applying the technology has been performed.

Dexin Wang

2012-03-31T23:59:59.000Z

179

Energy use by biological protein transport pathways  

E-Print Network [OSTI]

residing within energy-conserving membranes use transmembrane ion gradients to drive substrate transport receptors impart specificity to a targeting route, and transport across or into the membrane is typicallyEnergy use by biological protein transport pathways Nathan N. Alder1 and Steven M. Theg2 1

Economou, Tassos

180

RESEARCH PAPER The face value of ion fluxes: the challenge of determining  

E-Print Network [OSTI]

is the membrane-transport parameter of greatest interest to most researchers in the field of plant ion transport physiology. Key words: Barley, cellular ion exchange, efflux, high-affinity transport, influx, low-affinity transport, potassium. Introduction The unidirectional influx of nutrient ions into the plant cell

Britto, Dev T.

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Transport in JET H-mode Plasmas with Beam and Ion Cyclotron Heating  

SciTech Connect (OSTI)

Ion Cyclotron (IC) Range of Frequency waves and neutral beam (NB) injection are planned for heating in ITER and other future tokamaks. It is important to understand transport in plasmas with NB and IC to plan, predict, and improve transport and confinement. Transport predictions require simulations of the heating profiles, and for this, accurate modeling of the IC and NB heating is needed.

R.V. Budny, et. al.

2012-07-13T23:59:59.000Z

182

Mathematical modeling of liquid/liquid hollow fiber membrane contactor accounting for interfacial transport phenomena: Extraction of lanthanides as a surrogate for actinides  

SciTech Connect (OSTI)

This report is divided into two parts. The second part is divided into the following sections: experimental protocol; modeling the hollow fiber extractor using film theory; Graetz model of the hollow fiber membrane process; fundamental diffusive-kinetic model; and diffusive liquid membrane device-a rigorous model. The first part is divided into: membrane and membrane process-a concept; metal extraction; kinetics of metal extraction; modeling the membrane contactor; and interfacial phenomenon-boundary conditions-applied to membrane transport.

Rogers, J.D.

1994-08-04T23:59:59.000Z

183

Water uptake, ionic conductivity and swelling properties of anion-exchange membrane  

E-Print Network [OSTI]

occurs with negative excess volume of mixing. Percolative nature of the ion transport has been is reduced at the cathode to produce OH? , which transports through the anion-exchange membrane (AEM membrane, AEM can conduct ions only in the presence of water. In addition, water is one of the reactants

184

Direct numerical simulation of electroconvective instability and hysteretic current-voltage response of a permselective membrane  

E-Print Network [OSTI]

We present a systematic, multiscale, fully detailed numerical modeling for dynamics of fluid flow and ion transport covering Ohmic, limiting, and overlimiting current regimes in conductance of ion-selective membrane. By ...

Pham, Van Sang

185

The RCK Domain of the KtrAB K+ Transporter: Multiple Conformations  

E-Print Network [OSTI]

that is propagated to the membrane-bound protein, leading to ion transport (Jiang et al., 2002a; Roosild et al., 2002 transporter is a complex of the KtrB membrane protein and KtrA, an RCK do- main. RCK domains regulate eukaryotic and prokaryotic membrane proteins involved in K+ transport. Conflicting functional models have

Gruner, Sol M.

186

Neutron Reflectivity Study of Lipid Membranes Assembled on Ordered Nanocomposite and Nanoporous Silica Thin  

E-Print Network [OSTI]

moleculestrappedwithinthenanocompositethinfilmmay be used to detect trans-membrane transport (e.g., ion channel function). Furthermore, the ability in facilitating molecular transport across the membrane plane. In this regard, the use of ultrathin polymericNeutron Reflectivity Study of Lipid Membranes Assembled on Ordered Nanocomposite and Nanoporous

Parikh, Atul N.

187

Continuum electromechanical modeling of protein-membrane interactions Y. C. Zhou*  

E-Print Network [OSTI]

and topological transformations of membrane are crucial steps in numerous transport and signaling processes of cells, includ- ing cell migration, membrane trafficking, and ion conduc- tance 1­3 . There are various sorting complex required for transport III ESCRT III in- duced membrane budding or protrusion 5

Lu, Benzhuo

188

Staged membrane oxidation reactor system  

DOE Patents [OSTI]

Ion transport membrane oxidation system comprising (a) two or more membrane oxidation stages, each stage comprising a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, a reactant gas inlet region, a reactant gas outlet region, an oxidant gas inlet region, and an oxidant gas outlet region; (b) an interstage reactant gas flow path disposed between each pair of membrane oxidation stages and adapted to place the reactant gas outlet region of a first stage of the pair in flow communication with the reactant gas inlet region of a second stage of the pair; and (c) one or more reactant interstage feed gas lines, each line being in flow communication with any interstage reactant gas flow path or with the reactant zone of any membrane oxidation stage receiving interstage reactant gas.

Repasky, John Michael; Carolan, Michael Francis; Stein, VanEric Edward; Chen, Christopher Ming-Poh

2012-09-11T23:59:59.000Z

189

Staged membrane oxidation reactor system  

DOE Patents [OSTI]

Ion transport membrane oxidation system comprising (a) two or more membrane oxidation stages, each stage comprising a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, a reactant gas inlet region, a reactant gas outlet region, an oxidant gas inlet region, and an oxidant gas outlet region; (b) an interstage reactant gas flow path disposed between each pair of membrane oxidation stages and adapted to place the reactant gas outlet region of a first stage of the pair in flow communication with the reactant gas inlet region of a second stage of the pair; and (c) one or more reactant interstage feed gas lines, each line being in flow communication with any interstage reactant gas flow path or with the reactant zone of any membrane oxidation stage receiving interstage reactant gas.

Repasky, John Michael; Carolan, Michael Francis; Stein, VanEric Edward; Chen, Christopher Ming-Poh

2014-05-20T23:59:59.000Z

190

Staged membrane oxidation reactor system  

DOE Patents [OSTI]

Ion transport membrane oxidation system comprising (a) two or more membrane oxidation stages, each stage comprising a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, a reactant gas inlet region, a reactant gas outlet region, an oxidant gas inlet region, and an oxidant gas outlet region; (b) an interstage reactant gas flow path disposed between each pair of membrane oxidation stages and adapted to place the reactant gas outlet region of a first stage of the pair in flow communication with the reactant gas inlet region of a second stage of the pair; and (c) one or more reactant interstage feed gas lines, each line being in flow communication with any interstage reactant gas flow path or with the reactant zone of any membrane oxidation stage receiving interstage reactant gas.

Repasky, John Michael; Carolan, Michael Francis; Stein, VanEric Edward; Chen, Christopher Ming-Poh

2013-04-16T23:59:59.000Z

191

Production of permeable cellulose triacetate membranes  

DOE Patents [OSTI]

A phase inversion process for the preparation of cellulose triacetate (CTA) and regenerated cellulose membranes is disclosed. Such membranes are useful as supports for liquid membranes in facilitated transport processes, as microfiltration membranes, as dialysis or ultrafiltration membranes, and for the preparation of ion-selective electrodes. The process comprises the steps of preparing a casting solution of CTA in a solvent comprising a mixture of cyclohexanone and methylene chloride, casting a film from the casting solution, and immersing the cast film in a methanol bath. The resulting CTA membrane may then be hydrolyzed to regenerated cellulose using conventional techniques.

Johnson, B.M.

1986-12-23T23:59:59.000Z

192

Production of permeable cellulose triacetate membranes  

DOE Patents [OSTI]

A phase inversion process for the preparation of cellulose triacetate (CTA) and regenerated cellulose membranes is disclosed. Such membranes are useful as supports for liquid membranes in facilitated transport processes, as microfiltration membranes, as dialysis or ultrafiltration membranes, and for the preparation of ion-selective electrodes. The process comprises the steps of preparing a casting solution of CTA in a solvent comprising a mixture of cyclohexanone and methylene chloride, casting a film from the casting solution, and immersing the cast film in a methanol bath. The resulting CTA membrane may then be hydrolyzed to regenerated cellulose using conventional techniques.

Johnson, Bruce M. (Bend, OR)

1986-01-01T23:59:59.000Z

193

Generation, transport and focusing of high-brightness heavy ion beams  

E-Print Network [OSTI]

The Neutralized Transport Experiment (NTX) has been built at the Heavy Ion Fusion Virtual National Laboratory. NTX is the first successful integrated beam system experiment that explores various physical phenomena, and ...

Henestroza, Enrique

2006-01-01T23:59:59.000Z

194

Charged Amino Acids (R83, E567, D617, E625, R669, and K678) of CusA Are Required for Metal Ion Transport in the Cus Efflux System  

SciTech Connect (OSTI)

Gram-negative bacteria expel various toxic chemicals via tripartite efflux pumps belonging to the resistance-nodulation-cell division superfamily. These pumps span both the inner and outer membranes of the cell. The three components of these tripartite systems are an inner-membrane, substrate-binding transporter (or pump); a periplasmic membrane fusion protein (or adaptor); and an outer-membrane-anchored channel. These three efflux proteins interact in the periplasmic space to form the three-part complexes. We previously presented the crystal structures of both the inner-membrane transporter CusA and membrane fusion protein CusB of the CusCBA tripartite efflux system from Escherichia coli. We also described the co-crystal structure of the CusBA adaptor-transporter, revealing that the trimeric CusA efflux pump assembles with six CusB protein molecules to form the complex CusB{sub 6}-CusA{sub 3}. We here report three different conformers of the crystal structures of CusBA-Cu(I), suggesting a mechanism on how Cu(I) binding initiates a sequence of conformational transitions in the transport cycle. Genetic analysis and transport assays indicate that charged residues, in addition to the methionine pairs and clusters, are essential for extruding metal ions out of the cell.

Su, Chih-Chia; Long, Feng; Lei, Hsiang-Ting; Reddy Bolla, Jani; Do, Sylvia V.; Rajashankar, Kanagalaghatta R.; Yu, Edward W. (Cornell); (Iowa State)

2012-10-23T23:59:59.000Z

195

J. Membrane Biol. 4,179-192 (1971) 9 by Springer-Verlag New York Inc. 1971  

E-Print Network [OSTI]

antibiotics increase the ion permeability of biological membranes have been carried out on artificial model the possibility that they may serve as model systems for active transport across biological membranes. Moore and Pressman (1964) discovered the influence of valinomycin on the ion transport across the mitochondrial

Junge, Wolfgang

196

Evidence for a dynamic and transient pathway through the TAT protein transport machinery  

E-Print Network [OSTI]

, University of Florida, Gainesville FL, USA Tat systems transport completely folded proteins across ion Categories: membranes & transport; proteins Keywords: chloroplasts; protein transport; thylakoid; trans transport machinery in thylakoids (called cpTat) consists of three membrane proteins; Tha4, Hcf106, and cp

197

Radial transport of energetic ions in the presence of trapped electron mode turbulence  

SciTech Connect (OSTI)

The nature of transport of hot ions is studied in the presence of microturbulence generated by the trapped electron mode in a Tokamak using massively parallel, first principle based global nonlinear gyrokinetic simulation, and with the help of a passive tracer method. Passing and trapped hot ions are observed to exhibit inverse and inverse square scaling with energy, while those with isotropic pitch distribution are found to exhibit inverse dependence on energy. For all types of hot ions, namely, isotropic, passing, and trapped, the radial transport appears to be subdiffusive for the parameters considered.

Chowdhury, J.; Wang, W.; Ethier, S.; Manickam, J. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Ganesh, R. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

2011-11-15T23:59:59.000Z

198

Ann. N.Y. Acad. Sci. 986: 116126 (2003). 2003 New York Academy of Sciences. Ion Occlusion/Deocclusion Partial Reactions in  

E-Print Network [OSTI]

-type ion-motive ATPases, transported ions approach their binding sites from one membrane surface, become an alternating-gate transport mechanism, in which the pump acts like an ion channel with two gates that open ion transport, the probability of the pump's two gates being open simultaneously must be extremely low

Gadsby, David

199

Membrane formation by preferential solvation of ions in mixture of water, 3-methylpyridine, and sodium tetraphenylborate  

SciTech Connect (OSTI)

The structure and dynamics of a ternary system composed of deuterium oxide (D{sub 2}O), 3-methylpyridine (3MP), and sodium tetraphenylborate (NaBPh{sub 4}) are investigated by means of small-angle neutron scattering (SANS) and neutron spin echo (NSE) techniques. In the SANS experiments, a structural phase transition is confirmed between a disordered-phase and an ordered-lamellar-phase upon variation of the composition and/or temperature of the mixture. The characteristic lengths of the structures is on the sub-micrometer scale. A dispersion relation of the structure is measured through NSE experiments, which shows that the relaxation rate follows a cubic relation with momentum transfer. This implies that the dynamics of the system are determined predominantly by membrane fluctuations. The present results indicate that 3MP-rich domains are microscopically separated from bulk water in the presence of NaBPh{sub 4}, and that the layers behave as membranes. These results are interpreted that preferential solvation of salt in each solvent induces a microphase separation between the solvents, and the periodic structure of 3MP-rich domains is stabilized by the long-range electrostatic interaction arising from Na{sup +} ions in D{sub 2}O-rich domains.

Sadakane, Koichiro, E-mail: sadakane@fc.ritsumei.ac.jp [Department of Physics, Ritsumeikan University, Noji-Higashi 1-1-1, Kusatsu 525-8577 (Japan)] [Department of Physics, Ritsumeikan University, Noji-Higashi 1-1-1, Kusatsu 525-8577 (Japan); Nagao, Michihiro [NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-6102 (United States) [NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-6102 (United States); Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408-1398 (United States); Endo, Hitoshi; Seto, Hideki [KENS and CMRC, Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba 305-0801 (Japan)] [KENS and CMRC, Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba 305-0801 (Japan)

2013-12-21T23:59:59.000Z

200

Na K -pump ligands modulate gating of palytoxin-induced ion channels  

E-Print Network [OSTI]

proteins that mediate transport of ions across cell membranes, they traditionally have been viewed as very to the extracellular surface. The 3Na 2K -exchange transport cycle is completed when two extracellular K ions bind ensure the vectorial nature of net transport. The occluded-ion conformations, with binding sites

Gadsby, David

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Equivalence of trans paths in ion channels Juan Alvarez*  

E-Print Network [OSTI]

explore stochastic models for the study of ion transport in biological cells. Analysis of these models explains and explores an interesting feature of ion transport observed by biophysicists. Namely the interior and exterior of the cell. The membrane is a lipid bilayer that is essentially impermeable to ions

Hajek, Bruce

202

Transport and Failure in Li-ion Batteries | Stanford Synchrotron...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Li-ion Batteries Monday, February 13, 2012 - 1:30pm SSRL Conference Room 137-322 Stephen J. Harris, General Motors R&D While battery performance is well predicted by the...

203

Ion transport and structure of layer-by-layer assemblies  

E-Print Network [OSTI]

Layer-by-layer (LbL) films of various architectures were examined as potential solid state electrolytes for electrochemical systems (e.g. batteries and fuel cells). The relationship between materials properties and ion ...

Lutkenhaus, Jodie Lee

2007-01-01T23:59:59.000Z

204

ION CHANNELS The Na/K-ATPase/Src complex and cardiotonic  

E-Print Network [OSTI]

machine for the ATP-dependent and -coupled transport of Na+ and K+ across the plasma membrane of a living sarcoplasmic reticulum Ca-ATPase Introduction The P-type ATPases control ion fluxes across the cell membrane;allow the movement of ions across the cell membrane. They could also alter the function

Brand, Paul H.

205

ZERO EMISSION POWER PLANTS USING SOLID OXIDE FUEL CELLS AND OXYGEN TRANSPORT MEMBRANES  

SciTech Connect (OSTI)

Over 16,700 hours of operational experience was gained for the Oxygen Transport Membrane (OTM) elements of the proposed SOFC/OTM zero-emission power generation concept. It was repeatedly demonstrated that OTMs with no additional oxidation catalysts were able to completely oxidize the remaining depleted fuel in a simulated SOFC anode exhaust at an O{sub 2} flux that met initial targets. In such cases, neither residual CO nor H{sub 2} were detected to the limits of the gas chromatograph (<10 ppm). Dried OTM afterburner exhaust streams contained up to 99.5% CO{sub 2}. Oxygen flux through modified OTMs was double or even triple that of the standard OTMs used for the majority of testing purposes. Both the standard and modified membranes in laboratory-scale and demonstration-sized formats exhibited stable performance over extended periods (2300 to 3500 hours or 3 to 5 months). Reactor contaminants, were determined to negatively impact OTM performance stability. A method of preventing OTM performance degradation was developed and proven to be effective. Information concerning OTM and seal reliability over extended periods and through various chemical and thermal shocks and cycles was also obtained. These findings were used to develop several conceptual designs for pilot (10 kWe) and commercial-scale (250 kWe) SOFC/OTM zero emission power generation systems.

G. Maxwell Christie; Troy M. Raybold

2003-06-10T23:59:59.000Z

206

A Discussion of Conductivity Testing in High Temperature Membranes (lessons learned in assessing transport)  

Broader source: Energy.gov [DOE]

Presentation on conductivity testing in high temperature membranes given by Jim Boncella of Los Alamos National Laboratory at the High Temperature Membrane Working Group meeting in October 2005.

207

2002 Macmillan Magazines Ltd Ion gradients are widely used in transmembrane signal-  

E-Print Network [OSTI]

. These gradients are established by the active transport of ions from low to high electrochemical potentials across the membrane, driven by coupling transport to an energetically favourable process, such as ATP hydrolysis by ion channels that are located in the postsynaptic membrane and activated by neurotransmitters

Alford, Simon

208

Anomalous Electron Transport Due to Multiple High Frequency Beam Ion Driven Alfven Eigenmode  

SciTech Connect (OSTI)

We report on the simulations of recently observed correlations of the core electron transport with the sub-thermal ion cyclotron frequency instabilities in low aspect ratio plasmas of the National Spherical Torus Experiment (NSTX). In order to model the electron transport of the guiding center code ORBIT is employed. A spectrum of test functions of multiple core localized Global shear Alfven Eigenmode (GAE) instabilities based on a previously developed theory and experimental observations is used to examine the electron transport properties. The simulations exhibit thermal electron transport induced by electron drift orbit stochasticity in the presence of multiple core localized GAE.

N.N. Gorelenkov, D. Stutman, K. Tritz, A. Boozer, L. Delgardo-Aparicio, E. Fredrickson, S. Kaye, and R. White

2010-07-13T23:59:59.000Z

209

Two Chlamydomonas CTR Copper Transporters with a Novel Cys-Met Motif Are Localized to the Plasma Membrane and  

E-Print Network [OSTI]

Two Chlamydomonas CTR Copper Transporters with a Novel Cys-Met Motif Are Localized to the Plasma Membrane and Function in Copper Assimilation W M. Dudley Page, Janette Kropat, Patrice P. Hamel,1, California 90095-1569 Inducible high-affinity copper uptake is key to copper homeostasis in Chlamydomonas

Meier, Iris

210

Computer Simulation and Comparison of Proton and Carbon Ion Treatment of Tumor Cells Using Particle and Heavy Ion Transport Code System  

E-Print Network [OSTI]

COMPUTER SIMULATION AND COMPARISON OF PROTON AND CARBON ION TREATMENT OF TUMOR CELLS USING PARTICLE AND HEAVY ION TRANSPORT CODE SYSTEM A Thesis by KEEL BRANDON CURTIS Submitted to the Office of Graduate Studies of Texas A... AND HEAVY ION TRANSPORT CODE SYSTEM A Thesis by KEEL BRANDON CURTIS Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved by: Chair...

Curtis, Keel Brandon

2011-02-22T23:59:59.000Z

211

Recent Progress in the Research on Ion and Electron Transport in Gases at Swarm Energies  

SciTech Connect (OSTI)

This paper deals with the presentation and discussion of recent research on the transport of electrons and ions in gases at low energies. Particular emphasis is placed on electron swarm experiments related with the negative differential conductivity of electrons in some gas mixtures, and with secondary ionisation processes due to the impact of metastables with neutrals (Penning ionisation). Ion transport is firstly addressed through some recent measurements on atomic and molecular systems for which both theory and experiment have reached a high degree of agreement, and also on those in which the ranges of the density-normalized electric field intensity E/N have been increased substantiality. Also, the recent advances on the application of transport theories dealing with inelastic collisions are presented, as well as some recent measurements of negative ions and charged clusters in gaseous mixtures, leading to the successful test of Blanc's law at low fields, to the experimental mobilities.

Urquijo, Jaime de [Centro de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, P.O. Box 48-3, 62251, Cuernavaca, Mor. (Mexico)

2004-12-01T23:59:59.000Z

212

Self-Assembly and Mass Transport in Membranes for Artificial Photosynthesis  

E-Print Network [OSTI]

for artificial photosynthesis systems ..6Photosynthesis 7up process of artificial photosynthesis membranes and open

Modestino, Miguel Antonio

2013-01-01T23:59:59.000Z

213

208 | Intermodal transportatIon: movIng FreIght In a global economy 7.1 Introduction  

E-Print Network [OSTI]

208 | Intermodal transportatIon: movIng FreIght In a global economy #12;7 7.1 Introduction Air become an indispensible part of the world's global economy, holding an important niche in the transport al mutawaly | 209 2010 EnoTransportation Foundation.www.enotrans.com Reprinted from IntermodalTransportation:MovingFreightinaGlobalEconomy

Keskinocak, Pinar

214

A computational study of ion conductance in the KcsA K+ using a NernstPlanck model with explicit resident ions  

E-Print Network [OSTI]

membranes, new transport mechanisms evolved to allow ionized substrates into the cell and release ionized waste products into the environment.1 For the membrane to retain vital cell compo- nents, the transport the ion and wa- ter cannot get past each other transport devices such that every living cell in nearly all

Lu, Benzhuo

215

Angular neutron transport investigation in the HZETRN free-space ion and nucleon transport and shielding computer program  

SciTech Connect (OSTI)

Extension of the high charge and energy (HZE) transport computer program HZETRN for angular transport of neutrons is considered. For this paper, only light ion transport, He{sup 4} and lighter, will be analyzed using a pure solar proton source. The angular transport calculator is the ANISN/PC program which is being controlled by the HZETRN program. The neutron flux values are compared for straight-ahead transport and angular transport in one dimension. The shield material is aluminum and the target material is water. The thickness of these materials is varied; however, only the largest model calculated is reported which is 50 gm/cm{sup 2} of aluminum and 100 gm/cm{sup 2} of water. The flux from the ANISN/PC calculation is about two orders of magnitude lower than the flux from HZETRN for very low energy neutrons. It is only a magnitude lower for the neutrons in the 10 to 20 MeV range in the aluminum and two orders lower in the water. The major reason for this difference is in the transport modes: straight-ahead versus angular. The angular treatment allows a longer path length than the straight-ahead approximation. Another reason is the different cross section sets used by the ANISN/PC-BUGLE-80 mode and the HZETRN mode. The next step is to investigate further the differences between the two codes and isolate the differences to just the angular versus straight-ahead transport mode. Then, create a better coupling between the angular neutron transport and the charged particle transport.

Singleterry, R.C. Jr. [Argonne National Lab. - West, Idaho Falls, ID (United States); Wilson, J.W. [National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center

1997-05-01T23:59:59.000Z

216

Modeling chamber transport for heavy-ion fusion  

SciTech Connect (OSTI)

In a typical thick-liquid-wall scenario for heavy-ion fusion (HIF), between seventy and two hundred high-current beams enter the target chamber through ports and propagate about three meters to the target. Since molten-salt jets are planned to protect the chamber wall, the beams move through vapor from the jets, and collisions between beam ions and this background gas both strip the ions and ionize the gas molecules. Radiation from the preheated target causes further beam stripping and gas ionization. Due to this stripping, beams for heavy-ion fusion are expected to require substantial neutralization in a target chamber. Much recent research has, therefore, focused on beam neutralization by electron sources that were neglected in earlier simulations, including emission from walls and the target, photoionization by the target radiation, and pre-neutralization by a plasma generated along the beam path. When these effects are included in simulations with practicable beam and chamber parameters, the resulting focal spot is approximately the size required by a distributed radiator target.

Sharp, W.M.; Callahan, D.A.; Tabak, M.; Yu, S.S.; Peterson, P.F.; Welch, D.R.; Rose, D.V.; Olson, C.L.

2002-10-01T23:59:59.000Z

217

PHYSICAL REVIEW E 85, 031914 (2012) Ion fluxes through nanopores and transmembrane channels  

E-Print Network [OSTI]

]. The channels serve to establish an electrostatic potential gradient across the cell membrane by allowing an ion-specific flux to pass through the membrane. There are many different ion channels in living cells. They differ, in practice, it is well known that when open, ion channels sustain a very large ionic transport rate

Levin, Yan

218

Transport of ions in a segmented linear Paul trap in printed-circuit-board technology  

E-Print Network [OSTI]

We describe the construction and operation of a segmented linear Paul trap, fabricated in printed-circuit-board technology with an electrode segment width of 500 microns. We prove the applicability of this technology to reliable ion trapping and report the observation of Doppler cooled ion crystals of Ca-40 with this kind of traps. Measured trap frequencies agree with numerical simulations at the level of a few percent from which we infer a high fabrication accuracy of the segmented trap. To demonstrate its usefulness and versatility for trapped ion experiments we study the fast transport of a single ion. Our experimental results show a success rate of 99.0(1)% for a transport distance of 2x2mm in a round-trip time of T=20us, which corresponds to 4 axial oscillations only. We theoretically and experimentally investigate the excitation of oscillations caused by fast ion transports with error-function voltage ramps: For a slightly slower transport (a round-trip shuttle within T=30us) we observe non-adiabatic motional excitation of 0.89(15)meV.

G. Huber; T. Deuschle; W. Schnitzler; R. Reichle; K. Singer; F. Schmidt-Kaler

2007-11-19T23:59:59.000Z

219

J/psi production in relativistic heavy ion collisions from a multiphase transport model  

E-Print Network [OSTI]

for the present study is a hybrid model based on three Monte Carlo models for the three stages of relativistic heavy ion collisions, i.e., the heavy ion jet interaction generator J?c production in relativistic heavy ion collision Bin Zhang,1 C.M. Ko,2 Bao...V. With this dynamic transport model, we find that the net number of produced J/c from the parton and hadron phases is smaller than that expected from initial nucleon-nucleon collisions, contrary to the J/c en- ?2002 The American Physical Society1 ZHANG, KO, LI...

Zhang, B.; Ko, Che Ming; Li, Ba; Lin, ZW; Pal, S.

2002-01-01T23:59:59.000Z

220

Space Charge Compensation in the Linac4 Low Energy Beam Transport Line with Negative Hydrogen Ions  

E-Print Network [OSTI]

The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Tranport (LEBT) using the package IBSimu1, which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H- beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

Valerio-Lizarraga, C; Leon-Monzon, I; Lettry, J; Midttun, O; Scrivens, R

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Poisson-Nernst-Planck systems for narrow tubular-like membrane and Bixiang Wang  

E-Print Network [OSTI]

membrane channels, transport of holes and electrons in semiconductors (see, e.g., [1, 2, 24, 4, 6, 7, 8, 17, 25]). In the context of ion flow through membrane channels, it is physicallyPoisson-Nernst-Planck systems for narrow tubular-like membrane channels Weishi Liu and Bixiang Wang

Liu, Weishi

222

Direct photon emission in Heavy Ion Collisions from Microscopic Transport Theory and Fluid Dynamics  

E-Print Network [OSTI]

Direct photon emission in heavy-ion collisions is calculated within a relativistic micro+macro hybrid model and compared to the microscopic transport model UrQMD. In the hybrid approach, the high-density part of the collision is calculated by an ideal 3+1-dimensional hydrodynamic calculation, while the early (pre-equilibrium-) and late (rescattering-) phase are calculated with the transport model. Different scenarios of the transition from the macroscopic description to the transport model description and their effects are studied. The calculations are compared to measurements by the WA98-collaboration and predictions for the future CBM-experiment are made.

Bjoern Baeuchle; Marcus Bleicher

2010-03-29T23:59:59.000Z

223

Energetic-particle-driven instabilities and induced fast-ion transport in a reversed field pinch  

SciTech Connect (OSTI)

Multiple bursty energetic-particle (EP) driven modes with fishbone-like structure are observed during 1?MW tangential neutral-beam injection in a reversed field pinch (RFP) device. The distinguishing features of the RFP, including large magnetic shear (tending to add stability) and weak toroidal magnetic field (leading to stronger drive), provide a complementary environment to tokamak and stellarator configurations for exploring basic understanding of EP instabilities. Detailed measurements of the EP mode characteristics and temporal-spatial dynamics reveal their influence on fast ion transport. Density fluctuations exhibit a dynamically evolving, inboard-outboard asymmetric spatial structure that peaks in the core where fast ions reside. The measured mode frequencies are close to the computed shear Alfvn frequency, a feature consistent with continuum modes destabilized by strong drive. The frequency pattern of the dominant mode depends on the fast-ion species. Multiple frequencies occur with deuterium fast ions compared to single frequency for hydrogen fast ions. Furthermore, as the safety factor (q) decreases, the toroidal mode number of the dominant EP mode transits from n=5 to n=6 while retaining the same poloidal mode number m=1. The transition occurs when the m=1, n=5 wave-particle resonance condition cannot be satisfied as the fast-ion safety factor (q{sub fi}) decreases. The fast-ion temporal dynamics, measured by a neutral particle analyzer, resemble a classical predator-prey relaxation oscillation. It contains a slow-growth phase arising from the beam fueling followed by a rapid drop when the EP modes peak, indicating that the fluctuation-induced transport maintains a stiff fast-ion density profile. The inferred transport rate is strongly enhanced with the onset of multiple EP modes.

Lin, L.; Brower, D. L.; Ding, W. X. [Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095 (United States)] [Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095 (United States); Anderson, J. K.; Capecchi, W.; Eilerman, S.; Forest, C. B.; Koliner, J. J.; Nornberg, M. D.; Reusch, J.; Sarff, J. S. [Department of Physics, University of WisconsinMadison, Madison, Wisconsin 53706 (United States)] [Department of Physics, University of WisconsinMadison, Madison, Wisconsin 53706 (United States); Liu, D. [Department of Physics and Astronomy, University of California Irvine, Irvine, California 92697 (United States)] [Department of Physics and Astronomy, University of California Irvine, Irvine, California 92697 (United States)

2014-05-15T23:59:59.000Z

224

Transport of Energetic Ions due to Microturbulence, Sawteeth, and Alfven Eigenmodes  

E-Print Network [OSTI]

Transport of Energetic Ions due to Microturbulence, Sawteeth, and Alfven Eigenmodes D. C. Pace1 37831,USA 6 Princeton Plasma Physics Laboratory, PO Box 451, Princeton, New Jersey 08543-0451, USA 7. Utilizing an array of new diagnostics and simulation/modeling techniques, recent DIII-D experiments have

Lin, Zhihong

225

Active membrane fluctuations studied by micropipet aspiration J.-B. Manneville,1  

E-Print Network [OSTI]

, mostly performed by proteins embedded inside the lipid bi- layer, such as solute transport via ion channels or pumps, cell locomotion and adhesion, membrane transport through exo- cytic and endocyticActive membrane fluctuations studied by micropipet aspiration J.-B. Manneville,1 P. Bassereau,1

Ramaswamy, Sriram

226

Conformational Exchange in a Membrane Transport Protein Is Altered in Protein Crystals  

SciTech Connect (OSTI)

Successful macromolecular crystallography requires solution conditions that may alter the conformational sampling of a macromolecule. Here, site-directed spin labeling is used to examine a conformational equilibrium within BtuB, the Escherichia coli outer membrane transporter for vitamin B{sub 12}. Electron paramagnetic resonance (EPR) spectra from a spin label placed within the N-terminal energy coupling motif (Ton box) of BtuB indicate that this segment is in equilibrium between folded and unfolded forms. In bilayers, substrate binding shifts this equilibrium toward the unfolded form; however, EPR spectra from this same spin-labeled mutant indicate that this unfolding transition is blocked in protein crystals. Moreover, crystal structures of this spin-labeled mutant are consistent with the EPR result. When the free energy difference between substates is estimated from the EPR spectra, the crystal environment is found to alter this energy by 3 kcal/mol when compared to the bilayer state. Approximately half of this energy change is due to solutes or osmolytes in the crystallization buffer, and the remainder is contributed by the crystal lattice. These data provide a quantitative measure of how a conformational equilibrium in BtuB is modified in the crystal environment, and suggest that more-compact, less-hydrated substates will be favored in protein crystals.

D Freed; P Horanyi; M Wiener; D Cafiso

2011-12-31T23:59:59.000Z

227

Conformational Exchange in a Membrane Transport Protein Is Altered in Protein Crystals  

SciTech Connect (OSTI)

Successful macromolecular crystallography requires solution conditions that may alter the conformational sampling of a macromolecule. Here, site-directed spin labeling is used to examine a conformational equilibrium within BtuB, the Escherichia coli outer membrane transporter for vitamin B{sub 12}. Electron paramagnetic resonance (EPR) spectra from a spin label placed within the N-terminal energy coupling motif (Ton box) of BtuB indicate that this segment is in equilibrium between folded and unfolded forms. In bilayers, substrate binding shifts this equilibrium toward the unfolded form; however, EPR spectra from this same spin-labeled mutant indicate that this unfolding transition is blocked in protein crystals. Moreover, crystal structures of this spin-labeled mutant are consistent with the EPR result. When the free energy difference between substates is estimated from the EPR spectra, the crystal environment is found to alter this energy by 3 kcal/mol when compared to the bilayer state. Approximately half of this energy change is due to solutes or osmolytes in the crystallization buffer, and the remainder is contributed by the crystal lattice. These data provide a quantitative measure of how a conformational equilibrium in BtuB is modified in the crystal environment, and suggest that more-compact, less-hydrated substates will be favored in protein crystals.

Freed, Daniel M.; Horanyi, Peter S.; Wiener, Michael C.; Cafiso, David S. (UV)

2010-09-27T23:59:59.000Z

228

Space charge compensation in the Linac4 low energy beam transport line with negative hydrogen ions  

SciTech Connect (OSTI)

The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Transport using the package IBSimu [T. Kalvas et al., Rev. Sci. Instrum. 81, 02B703 (2010)], which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H{sup ?} beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

Valerio-Lizarraga, Cristhian A., E-mail: cristhian.alfonso.valerio.lizarraga@cern.ch [CERN, Geneva (Switzerland); Departamento de Investigacin en Fsica, Universidad de Sonora, Hermosillo (Mexico); Lallement, Jean-Baptiste; Lettry, Jacques; Scrivens, Richard [CERN, Geneva (Switzerland)] [CERN, Geneva (Switzerland); Leon-Monzon, Ildefonso [Facultad de Ciencias Fisico-Matematicas, Universidad Autnoma de Sinaloa, Culiacan (Mexico)] [Facultad de Ciencias Fisico-Matematicas, Universidad Autnoma de Sinaloa, Culiacan (Mexico); Midttun, ystein [CERN, Geneva (Switzerland) [CERN, Geneva (Switzerland); University of Oslo, Oslo (Norway)

2014-02-15T23:59:59.000Z

229

Genes Related to Ion-Transport and Energy Production Are Upregulated in Response to CO2-Driven pH Decrease  

E-Print Network [OSTI]

Genes Related to Ion-Transport and Energy Production Are Upregulated in Response to CO2-Driven p. (2013) Genes Related to Ion-Transport and Energy Production Are Upregulated in Response to CO2-Driven p

Paris-Sud XI, Université de

230

Membrane architectures for ion-channel switch-based electrochemical biosensors  

DOE Patents [OSTI]

The present invention is directed to a process of forming a bilayer lipid membrane structure by depositing an organic layer having a defined surface area onto an electrically conductive substrate, removing portions of said organic layer upon said electrically conductive substrate whereby selected portions of said organic layer are removed to form defined voids within said defined surface area of said organic layer and defined islands of organic layer upon said electrically conductive substrate, and, depositing a bilayer lipid membrane over the defined voids and defined islands of organic layer upon said substrate whereby aqueous reservoirs are formed between said electrically conductive substrate and said bilayer lipid membrane, said bilayer lipid membrane characterized as spanning across the defined voids between said defined islands. A lipid membrane structure is also described together with an array of such lipid membrane structure.

Sansinena, Jose-Maria (Los Alamos, NM); Redondo, Antonio (Los Alamos, NM); Swanson, Basil I. (Los Alamos, NM); Yee, Chanel Kitmon (Davis, CA); Sapuri/Butti, Annapoorna R. (Davis, CA); Parikh, Atul N. (Woodland, CA); Yang, Calvin (Davis, CA)

2008-10-28T23:59:59.000Z

231

Aptamer Directly Evolved from Live Cells Recognizes Membrane Bound Immunoglobin  

E-Print Network [OSTI]

. These include cell signaling, cell-cell interactions, ion/solute transport that facilitates the exchangeAptamer Directly Evolved from Live Cells Recognizes Membrane Bound Immunoglobin Heavy Mu Chain, and Weihong Tan The identification of tumor related cell membrane protein targets is important

Tan, Weihong

232

Deletions of SKY1 or PTK2 in the Saccharomyces cerevisiae trk1Dtrk2D mutant cells exert dual effect on ion homeostasis  

E-Print Network [OSTI]

that regulate ion transport across the plasma membrane of Saccharomyces cerevisiae. We show here that deletion to spermine and salt ions. A model that integrates these results to explain the mechanism of ion transport on ion homeostasis Omri Erez and Chaim Kahana* Department of Molecular Genetics, Weizmann Institute

Kahana, Chaim

233

Packing Interactions between Transmembrane Helices Alter Ion Selectivity of the Yeast Golgi Ca2  

E-Print Network [OSTI]

(SERCA) and plasma membrane (PMCA) Ca2 - ATPases (3, 4). Perhaps the most interesting transport charac- teristic of SPCA pumps is their unique ability to transport Mn2 ions with high affinity (1, 2 of the binding pocket resulting in vectorial ion transport (7). The x-ray crystal struc- ture of SERCA in the E1

Rao, Rajini

234

Conceptual design report for a Direct Hydrogen Proton Exchange Membrane Fuel Cell for transportation application  

SciTech Connect (OSTI)

This report presents the conceptual design for a Direct-Hydrogen-Fueled Proton Exchange Membrane (PEM) Fuel Cell System for transportation applications. The design is based on the initial selection of the Chrysler LH sedan as the target vehicle with a 50 kW (gross) PEM Fuel Cell Stack (FCS) as the primary power source, a battery-powered Load Leveling Unit (LLU) for surge power requirements, an on-board hydrogen storage subsystem containing high pressure gaseous storage, a Gas Management Subsystem (GMS) to manage the hydrogen and air supplies for the FCS, and electronic controllers to control the electrical system. The design process has been dedicated to the use of Design-to-Cost (DTC) principles. The Direct Hydrogen-Powered PEM Fuel Cell Stack Hybrid Vehicle (DPHV) system is designed to operate on the Federal Urban Driving Schedule (FUDS) and Hiway Cycles. These cycles have been used to evaluate the vehicle performance with regard to range and hydrogen usage. The major constraints for the DPHV vehicle are vehicle and battery weight, transparency of the power system and drive train to the user, equivalence of fuel and life cycle costs to conventional vehicles, and vehicle range. The energy and power requirements are derived by the capability of the DPHV system to achieve an acceleration from 0 to 60 MPH within 12 seconds, and the capability to achieve and maintain a speed of 55 MPH on a grade of seven percent. The conceptual design for the DPHV vehicle is shown in a figure. A detailed description of the Hydrogen Storage Subsystem is given in section 4. A detailed description of the FCS Subsystem and GMS is given in section 3. A detailed description of the LLU, selection of the LLU energy source, and the power controller designs is given in section 5.

NONE

1995-09-05T23:59:59.000Z

235

Membrane Porters of ATP-Binding Cassette Transport Systems Are Polyphyletic  

E-Print Network [OSTI]

REVIEW Membrane Porters of ATP-Binding Cassette Transportat Springerlink.com Abstract The ATP-binding cassette (ABC)classi?ed according to the ATP hydrolyzing constituents,

Wang, Bin; Dukarevich, Maxim; Sun, Eric I.; Yen, Ming Ren; Saier, Milton H.

2009-01-01T23:59:59.000Z

236

Anomalous transport effects and possible environmental symmetry "violation" in heavy ion collisions  

E-Print Network [OSTI]

The heavy ion collision provides a unique many-body environment where local domains of strongly interacting chiral medium may occur and in a sense allow environmental symmetry "violation" phenomena. For example certain anomalous transport processes, forbidden in usual medium, become possible in such domains. We briefly review recent progress in both the theoretical understanding and experimental search of various anomalous transport effects (such as the Chiral Magnetic Effect, Chiral Separation Effect, Chiral Electric Separation Effect, Chiral Electric/Magnetic Waves, etc) in the hot QCD fluid created by such collisions.

Jinfeng Liao

2015-02-27T23:59:59.000Z

237

Toroidal ripple transport of beam ions in the mega-ampere spherical tokamak  

SciTech Connect (OSTI)

The transport of injected beam ions due to toroidal magnetic field ripple in the mega-ampere spherical tokamak (MAST) is quantified using a full orbit particle tracking code, with collisional slowing-down and pitch-angle scattering by electrons and bulk ions taken into account. It is shown that the level of ripple losses is generally rather low, although it depends sensitively on the major radius of the outer midplane plasma edge; for typical values of this parameter in MAST plasmas, the reduction in beam heating power due specifically to ripple transport is less than 1%, and the ripple contribution to beam ion diffusivity is of the order of 0.1 m{sup 2} s{sup -1} or less. It is concluded that ripple effects make only a small contribution to anomalous transport rates that have been invoked to account for measured neutron rates and plasma stored energies in some MAST discharges. Delayed (non-prompt) losses are shown to occur close to the outer midplane, suggesting that banana-drift diffusion is the most likely cause of the ripple-induced losses.

McClements, K. G. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Hole, M. J. [Plasma Research Laboratory, Research School of Physical Science and Engineering, Australian National University, Canberra, ACT 0200 (Australia)

2012-07-15T23:59:59.000Z

238

Ion and electron local transport inside single helicity islands in the reversed field pinch  

SciTech Connect (OSTI)

The ion and electron diffusion coefficients inside the helical magnetic core in a single helicity reversed field pinch (RFP) toroidal plasma have been numerical determined by a Monte Carlo test particle approach. A new algorithm aimed at approximating with polyhedra the magnetic surfaces obtained with Poincare cross sections has been developed. Stationary simulations of test ion and electron transport have been performed: they allow the determination of the average diffusion coefficients inside the helical core both for ions and electrons, which are much lower than those found in standard multiple helicity plasmas. Results are discussed and compared with those found in previous RFP simulations. The technique may be relevant also for stellarator and tokamak studies.

Gobbin, M.; Marrelli, L.; Martin, P.; White, R. B. [Consorzio RFX, Associazione Euratom-ENEA sulla Fusione, Padova (Italy) and Dipartimento di Fisica, Universita di Padova, Padova (Italy); Consorzio RFX, Associazione Euratom-ENEA sulla Fusione, Padova (Italy); Consorzio RFX, Associazione Euratom-ENEA sulla Fusione, Padova (Italy) and Dipartimento di Fisica, Universita di Padova, Padova (Italy); Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)

2007-07-15T23:59:59.000Z

239

Self-Assembly and Mass Transport in Membranes for Artificial Photosynthesis  

E-Print Network [OSTI]

45 CHAPTER 3. SELF-ASSEMBLY AND TRANSPORT LIMITATIONS IN7371. CHAPTER 3. SELF-ASSEMBLY AND TRANSPORT LIMITATIONS IN2. CONTROLLING NANOROD SELF-ASSEMBLY IN POLYMER THIN-FILMS

Modestino, Miguel Antonio

2013-01-01T23:59:59.000Z

240

Investigation of the performance and water transport of a polymer electrolyte membrane (pem) fuel cell  

E-Print Network [OSTI]

Fuel cell performance was obtained as functions of the humidity at the anode and cathode sites, back pressure, flow rate, temperature, and channel depth. The fuel cell used in this work included a membrane and electrode assembly (MEA) which...

Park, Yong Hun

2009-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Experimental characterization of water sorption and transport properties of polymer electrolyte membranes for fuel cells.  

E-Print Network [OSTI]

??L'objectif gnral de cette thse de doctorat est de caractriser les proprits de membranes PFSA de type Nafion N115 et Nafion NRE212 en termes de (more)

Maldonado Snchez, Libeth

2012-01-01T23:59:59.000Z

242

Self-Assembly and Mass Transport in Membranes for Artificial Photosynthesis  

E-Print Network [OSTI]

membranes are in hydrogen fuel- cells and electrolyzers. Thefuel cells and electrolyzers used both for hydrogenhydrogen production and device geometry requirements dictated by the light absorption. In fuel cells,

Modestino, Miguel Antonio

2013-01-01T23:59:59.000Z

243

Benchmarking Heavy Ion Transport Codes FLUKA, HETC-HEDS MARS15, MCNPX, and PHITS  

SciTech Connect (OSTI)

Powerful accelerators such as spallation neutron sources, muon-collider/neutrino facilities, and rare isotope beam facilities must be designed with the consideration that they handle the beam power reliably and safely, and they must be optimized to yield maximum performance relative to their design requirements. The simulation codes used for design purposes must produce reliable results. If not, component and facility designs can become costly, have limited lifetime and usefulness, and could even be unsafe. The objective of this proposal is to assess the performance of the currently available codes â?? PHITS, FLUKA, MARS15, MCNPX, and HETC-HEDS â?? that could be used for design simulations involving heavy ion transport. We plan to access their performance by performing simulations and comparing results against experimental data of benchmark quality. Quantitative knowledge of the biases and the uncertainties of the simulations is essential as this potentially impacts the safe, reliable and cost effective design of any future radioactive ion beam facility. Further benchmarking of heavy-ion transport codes was one of the actions recommended in the â??Report of the 2003 RIA R&D Workshop".

Ronningen, Reginald Martin [Michigan State University; Remec, Igor [Oak Ridge National Laboratory; Heilbronn, Lawrence H. [University of Tennessee-Knoxville

2013-06-07T23:59:59.000Z

244

Computational and experimental study of nanoporous membranes for water desalination and decontamination.  

SciTech Connect (OSTI)

Fundamentals of ion transport in nanopores were studied through a joint experimental and computational effort. The study evaluated both nanoporous polymer membranes and track-etched nanoporous polycarbonate membranes. The track-etched membranes provide a geometrically well characterized platform, while the polymer membranes are more closely related to ion exchange systems currently deployed in RO and ED applications. The experimental effort explored transport properties of the different membrane materials. Poly(aniline) membranes showed that flux could be controlled by templating with molecules of defined size. Track-etched polycarbonate membranes were modified using oxygen plasma treatments, UV-ozone exposure, and UV-ozone with thermal grafting, providing an avenue to functionalized membranes, increased wettability, and improved surface characteristic lifetimes. The modeling effort resulted in a novel multiphysics multiscale simulation model for field-driven transport in nanopores. This model was applied to a parametric study of the effects of pore charge and field strength on ion transport and charge exclusion in a nanopore representative of a track-etched polycarbonate membrane. The goal of this research was to uncover the factors that control the flux of ions through a nanoporous material and to develop tools and capabilities for further studies. Continuation studies will build toward more specific applications, such as polymers with attached sulfonate groups, and complex modeling methods and geometries.

Hickner, Michael A. (Penn State University, University Park, PA); Chinn, Douglas Alan (Sandia National Laboratories, Albuquerque, NM); Adalsteinsson, Helgi; Long, Kevin R. (Texas Tech University, Lubbock, TX); Kent, Michael Stuart (Sandia National Laboratories, Albuquerque, NM); Debusschere, Bert J.; Zendejas, Frank J.; Tran, Huu M.; Najm, Habib N.; Simmons, Blake Alexander

2008-11-01T23:59:59.000Z

245

Super Boiler: Packed Media/Transport Membrane Boiler Development and Demonstration  

SciTech Connect (OSTI)

Gas Technology Institute (GTI) and Cleaver-Brooks developed a new gas-fired steam generation system???¢????????the Super Boiler???¢????????for increased energy efficiency, reduced equipment size, and reduced emissions. The system consists of a firetube boiler with a unique staged furnace design, a two-stage burner system with engineered internal recirculation and inter-stage cooling integral to the boiler, unique convective pass design with extended internal surfaces for enhanced heat transfer, and a novel integrated heat recovery system to extract maximum energy from the flue gas. With these combined innovations, the Super Boiler technical goals were set at 94% HHV fuel efficiency, operation on natural gas with <5 ppmv NOx (referenced to 3%O2), and 50% smaller than conventional boilers of similar steam output. To demonstrate these technical goals, the project culminated in the industrial demonstration of this new high-efficiency technology on a 300 HP boiler at Clement Pappas, a juice bottler located in Ontario, California. The Super Boiler combustion system is based on two stage combustion which combines air staging, internal flue gas recirculation, inter-stage cooling, and unique fuel-air mixing technology to achieve low emissions rather than external flue gas recirculation which is most commonly used today. The two-stage combustion provides lower emissions because of the integrated design of the boiler and combustion system which permit precise control of peak flame temperatures in both primary and secondary stages of combustion. To reduce equipment size, the Super Boiler's dual furnace design increases radiant heat transfer to the furnace walls, allowing shorter overall furnace length, and also employs convective tubes with extended surfaces that increase heat transfer by up to 18-fold compared to conventional bare tubes. In this way, a two-pass boiler can achieve the same efficiency as a traditional three or four-pass firetube boiler design. The Super Boiler is consequently up to 50% smaller in footprint, has a smaller diameter, and is up to 50% lower in weight, resulting in very compact design with reduced material cost and labor costs, while requiring less boiler room floor space. For enhanced energy efficiency, the heat recovery system uses a transport membrane condenser (TMC), a humidifying air heater (HAH), and a split-stage economizer to extract maximum energy from the flue gas. The TMC is a new innovation that pulls a major portion of water vapor produced by the combustion process from the flue gases along with its sensible and latent heat. This results in nearly 100% transfer of heat to the boiler feed water. The HAH improves the effectiveness of the TMC, particularly in steam systems that do not have a large amount of cold makeup water. In addition, the HAH humidifies the combustion air to reduce NOx formation. The split-stage economizer preheats boiler feed water in the same way as a conventional economizer, but extracts more heat by working in tandem with the TMC and HAH to reduce flue gas temperature. These components are designed to work synergistically to achieve energy efficiencies of 92-94% which is 10-15% higher than today???¢????????s typical firetube boilers.

Liss, William E; Cygan, David F

2013-04-17T23:59:59.000Z

246

Nanowire-integrated microporous silicon membrane for continuous fluid transport in micro cooling device  

SciTech Connect (OSTI)

We report an efficient passive micro pump system combining the physical properties of nanowires and micropores. This nanowire-integrated microporous silicon membrane was created to feed coolant continuously onto the surface of the wick in a micro cooling device to ensure it remains hydrated and in case of dryout, allow for regeneration of the system. The membrane was fabricated by photoelectrochemical etching to form micropores followed by hydrothermal growth of nanowires. This study shows a promising approach to address thermal management challenges for next generation electronic devices with absence of external power.

So, Hongyun; Pisano, Albert P. [Department of Mechanical Engineering, Berkeley Sensor and Actuator Center, University of California, Berkeley, California 94720 (United States)] [Department of Mechanical Engineering, Berkeley Sensor and Actuator Center, University of California, Berkeley, California 94720 (United States); Cheng, Jim C. [Department of Electrical Engineering, Berkeley Sensor and Actuator Center, University of California, Berkeley, California 94720 (United States)] [Department of Electrical Engineering, Berkeley Sensor and Actuator Center, University of California, Berkeley, California 94720 (United States)

2013-10-14T23:59:59.000Z

247

Measurements of water uptake and transport properties in anion-exchange membranes  

E-Print Network [OSTI]

the cost of the fuel cell systems. Although promising, conventional liquid electrolyte- based alkaline fuel Keywords: Direct ethanol fuel cells Anion-exchange membrane Water uptake Water diffusivity Mass. All rights reserved. 1. Introduction Alkaline fuel cells allow the use of non-platinum (Pt) catalysts

Zhao, Tianshou

248

Effect of ion mass and charge state on transport of vacuum ARC plasmas through a biased magnetic filter  

SciTech Connect (OSTI)

The effect of ion mass and charge state on plasma transport through a 90{sup o}-curved magnetic filter is experimentally investigated using a pulsed cathodic arc source. Graphite, copper, and tungsten were selected as test materials. The filter was a bent copper coil biased via the voltage drop across a low-ohm, ''self-bias'' resistor. Ion transport is accomplished via a guiding electric field, whose potential forms a ''trough'' shaped by the magnetic guiding field of the filter coil. Evaluation was done by measuring the filtered ion current and determination of the particle system coefficient, which can be defined as the ratio of filter ion current, divided by the mean ion charge state, to the arc current. It was found that the ion current and particle system coefficient decreased as the mass-to-charge ratio of ions increased. This result can be qualitatively interpreted by a very simply model of ion transport that is based on compensation of the centrifugal force by the electric force associated with the guiding potential trough.

Byon, Eungsun; Kim, Jong-Kuk; Kwon, Sik-Chol; Anders, Andre

2003-12-01T23:59:59.000Z

249

Method and system for producing hydrogen using sodium ion separation membranes  

DOE Patents [OSTI]

A method of producing hydrogen from sodium hydroxide and water is disclosed. The method comprises separating sodium from a first aqueous sodium hydroxide stream in a sodium ion separator, feeding the sodium produced in the sodium ion separator to a sodium reactor, reacting the sodium in the sodium reactor with water, and producing a second aqueous sodium hydroxide stream and hydrogen. The method may also comprise reusing the second aqueous sodium hydroxide stream by combining the second aqueous sodium hydroxide stream with the first aqueous sodium hydroxide stream. A system of producing hydrogen is also disclosed.

Bingham, Dennis N; Klingler, Kerry M; Turner, Terry D; Wilding, Bruce M; Frost, Lyman

2013-05-21T23:59:59.000Z

250

Joining of Ion Transport Membranes Using a Novel Transient Liquid Phase Process  

SciTech Connect (OSTI)

The feasibility of a novel transient liquid phase (TLP) joining method has been demonstrated in joining La{sub 0.9}Ca{sub 0.1}FeO{sub 3} materials. Metal oxide powders were processed to form the TLP compositions which were used in the joining process. The method has been successful in producing joint interfaces that effectively disappear, as they are the same material and have the same properties as the joined parts. The feasibility of the method has been demonstrated for a single system, but many systems where the method can potentially be applied have been identified.

Darryl P. Butt

2006-08-30T23:59:59.000Z

251

Compounds having aromatic rings and side-chain amide-functionality and a method for transporting monovalent anions across biological membranes using the same  

DOE Patents [OSTI]

A compound containing at least two aromatic rings covalently bonded together, with each aromatic ring containing at least one oxyacetamide-based side chain, the compound being capable of forming a chloride ion channel across a lipid bilayer, and transporting chloride ion across the lipid bilayer.

Davis, Jeffery T. (College Park, MD); Sidorov, Vladimir (Richmond, VA); Kotch, Frank W. (New Phila., PA)

2008-04-08T23:59:59.000Z

252

Zinc and Health: Current Status and Future Directions Zinc Transport in the Brain: Routes of Zinc Influx and Efflux in Neurons1,2  

E-Print Network [OSTI]

homeostasis. J. Nutr. 130: 1484S--1487S, 2000. KEY WORDS: zinc ion transport heavy metal ions trace and that mediate extracellular zinc toxicity and (3) a plasma membrane transporter potentially present in all elements metal transporters rat Large amounts of zinc are present in the brain, yet very little

253

Multi-block sulfonated poly(phenylene) copolymer proton exchange membranes  

DOE Patents [OSTI]

Improved multi-block sulfonated poly(phenylene) copolymer compositions, methods of making the same, and their use as proton exchange membranes (PEM) in hydrogen fuel cells, direct methanol fuel cells, in electrode casting solutions and electrodes. The multi-block architecture has defined, controllable hydrophobic and hydrophilic segments. These improved membranes have better ion transport (proton conductivity) and water swelling properties.

Fujimoto, Cy H. (Albuquerque, NM); Hibbs, Michael (Albuquerque, NM); Ambrosini, Andrea (Albuquerque, NM)

2012-02-07T23:59:59.000Z

254

Investigating the adsorption and transport of water in MFI zeolite pores for water desalination  

E-Print Network [OSTI]

The permeability of reverse osmosis membranes is limited by the diffusive transport of water across a non-porous polyamide active layer. Alternatively, fabricating a microporous active layer capable of rejecting salt ions ...

Humplik, Thomas

2010-01-01T23:59:59.000Z

255

Ammonium Bicarbonate Transport in Anion Exchange Membranes for Salinity Gradient Energy  

E-Print Network [OSTI]

such as reverse electrodialysis (RED) rely on highly selective anion transport through polymeric anion exchange to address global energy needs, such as reverse electro- dialysis1-4 (RED), capacitive energy extraction based on Donnan potential5 (CDP), and capacitive reverse electro- dialysis6 (CRED), has encouraged

256

Assembly and Repair of Membrane-Bound Electron Transport Complexes similar to NifS than is Slr0387, but shows strong  

E-Print Network [OSTI]

Assembly and Repair of Membrane-Bound Electron Transport Complexes similar to NifS than is Slr0387 in the maturation of FeS proteins. We found that under some conditions the Synechocystis NifU-like protein can oxidation of the cysteine side chains at NifU. The same reaction might have occurred in lysed chloroplasts

257

Proton conducting ceramic membranes for hydrogen separation  

DOE Patents [OSTI]

A multi-phase proton conducting material comprising a proton-conducting ceramic phase and a stabilizing ceramic phase. Under the presence of a partial pressure gradient of hydrogen across the membrane or under the influence of an electrical potential, a membrane fabricated with this material selectively transports hydrogen ions through the proton conducting phase, which results in ultrahigh purity hydrogen permeation through the membrane. The stabilizing ceramic phase may be substantially structurally and chemically identical to at least one product of a reaction between the proton conducting phase and at least one expected gas under operating conditions of a membrane fabricated using the material. In a barium cerate-based proton conducting membrane, one stabilizing phase is ceria.

Elangovan, S. (South Jordan, UT); Nair, Balakrishnan G. (Sandy, UT); Small, Troy (Midvale, UT); Heck, Brian (Salt Lake City, UT)

2011-09-06T23:59:59.000Z

258

Initialization of hydrodynamics in relativistic heavy ion collisions with an energy-momentum transport model  

E-Print Network [OSTI]

A key ingredient of hydrodynamical modeling of relativistic heavy ion collisions is thermal initial conditions, an input that is the consequence of a pre-thermal dynamics which is not completely understood yet. In the paper we employ a recently developed energy-momentum transport model of the pre-thermal stage to study influence of the alternative initial states in nucleus-nucleus collisions on flow and energy density distributions of the matter at the starting time of hydrodynamics. In particular, the dependence of the results on isotropic and anisotropic initial states is analyzed. It is found that at the thermalization time the transverse flow is larger and the maximal energy density is higher for the longitudinally squeezed initial momentum distributions. The results are also sensitive to the relaxation time parameter, equation of state at the thermalization time, and transverse profile of initial energy density distribution: Gaussian approximation, Glauber Monte Carlo profiles, etc. Also, test results ensure that the numerical code based on the energy-momentum transport model is capable of providing both averaged and fluctuating initial conditions for the hydrodynamic simulations of relativistic nuclear collisions.

V. Yu. Naboka; S. V. Akkelin; Iu. A. Karpenko; Yu. M. Sinyukov

2015-01-14T23:59:59.000Z

259

Effect of resistivity gradient on laser-driven electron transport and ion acceleration  

SciTech Connect (OSTI)

The effect of resistivity gradient on laser-driven electron transport and ion acceleration is investigated using collisional particle-in-cell simulation. The study is motivated by recent proton acceleration experiments [Gizzi et al., Phys. Rev. ST Accel. Beams 14, 011301 (2011)], which showed significant effect of the resistivity gradient in layered targets on the proton angular spread. This effect is reproduced in the present simulations. It is found that resistivity-gradient generation of magnetic fields and inhibition of electron transport is significantly enhanced when the feedback interaction between the magnetic field and the fast-electron current is included. Filamentation of the laser-generated hot electron jets inside the target, considered as the origin of the nonuniform proton patterns observed in the experiments, is clearly suppressed by the resistive magnetic field. As a result, the electrostatic sheath field at the target back surface acquires a relatively smooth profile, which contributes to the superior quality of the proton beams accelerated off layered targets in the experiments.

Zhuo, H. B.; Yang, X. H.; Ma, Y. Y.; Li, X. H. [College of Science, National University of Defense Technology, Changsha 410073 (China)] [College of Science, National University of Defense Technology, Changsha 410073 (China); Zhou, C. T. [College of Science, National University of Defense Technology, Changsha 410073 (China) [College of Science, National University of Defense Technology, Changsha 410073 (China); Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Yu, M. Y. [Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China) [Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Institute for Theoretical Physics I, Ruhr University, Bochum D-44780 (Germany)

2013-09-15T23:59:59.000Z

260

Enhanced Li+ ion transport in LiNi0.5Mn1.5O4 through Control...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Citation: Zheng J, J Xiao, X Yu, L Kovarik, M Gu, F Omenya, X Chen, XQ Yang, J Liu, GL Graff, MS Whittingham, and J Zhang.2012."Enhanced Li+ ion transport in LiNi0.5Mn1.5O4...

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Phys. Med. Biol. 45 (2000) N157N165. Printed in the UK PII: S0031-9155(00)14256-3 Hydrodynamic effects on the solute transport across  

E-Print Network [OSTI]

Hydrodynamic effects on the solute transport across endothelial pores and hepatocyte membranes Dumitru Popescu, Liviu Movileanu§¶, Stelian Ion and Maria-Luiza Flonta Membrane Biophysics Laboratory, Institute membranes (Abidor et al 1979, Popescu et al 1991, Popescu and Victor 1991, Weaver and Chizmadzhev 1996

Movileanu, Liviu

262

Highly Confined Photon Transport in Subwavelength Metallic Slot Waveguides  

E-Print Network [OSTI]

was deposited on one side of a free-standing Si3N4 membrane. Using focused ion- beam milling, wire waveguidesHighly Confined Photon Transport in Subwavelength Metallic Slot Waveguides J. A. Dionne,*, H. J and electronic components. Although optical interconnects exhibit a large bandwidth for signal transport, minimum

Atwater, Harry

263

Molecular Squares as Molecular Sieves: Size-Selective Transport Through  

E-Print Network [OSTI]

Molecular Squares as Molecular Sieves: Size-Selective Transport Through Porous-Membrane squaresº: cyclic structures typically featuring metal-ion cor- ners and difunctional bridging ligands processes: size-selective molecular transport from a guest-containing solution to one initially free

264

A model for transport and agglomeration of particles in reactive ion etching plasma reactors  

E-Print Network [OSTI]

drag, electrostatic, neutral drag, thermophoretic, gravitational, and self-diffusion. Ion drag forces

Kushner, Mark

265

J. Am. Chem. SOC.1994,116, 11203-11204 11203 Selective Dopamine Transport Using a Crown  

E-Print Network [OSTI]

with an ability to selectively transport catecholamines through a lipophilic membrane. In this report we describe ammonium ion^.^^^ With these systems, the order of observed transport rates has been primarily determinedJ. Am. Chem. SOC.1994,116, 11203-11204 11203 Selective Dopamine Transport Using a Crown Boronic

Smith, Bradley D.

266

E-Print Network 3.0 - ammonium ion transport Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

non-commercial research Summary: gaseous ammonia (NH3) which through chemical reaction in rainwater changes into ammonium ion (NH4... a means for the formation of ammonium ion (NH4...

267

Application of Momentum Transfer Theory for Ion and Electron Transport in Pure Gases and in Gas Mixtures  

SciTech Connect (OSTI)

In this paper we have presented two applications of Momentum Transfer Theory (MTT), which were both aimed at obtaining reliable data for modeling of non-equilibrium plasma. Transport properties of ion swarms in presence of Resonant Charge Transfer (RCT) collisions are studied using Momentum Transfer Theory (MTT). Using the developed MTT we tested a previously available anisotropic set of cross-sections for Ar++Ar collisions bay making the comparisons with the available data for the transverse diffusion coefficient. We also developed an anisotropic set of Ne++Ne integral cross-sections based on the available data for mobility, longitudinal and transverse diffusion. Anisotropic sets of cross-sections are needed for Monte Carlo simulations of ion transport and plasma models. Application of Blanc's Law for drift velocities of electrons and ions in gas mixtures at arbitrary reduced electric field strengths E/n0 was studied theoretically and by numerical examples. Corrections for Blanc's Law that include effects of inelastic collisions were derived. In addition we have derived the common mean energy procedure that was proposed by Chiflikian in a general case both for ions and electrons. Both corrected common E/n0 and common mean energy procedures provide excellent results even for electrons at moderate E/n0 where application of Blanc's Law was regarded as impossible. In mixtures of two gases that have negative differential conductivity (NDC) even when neither of the two pure gases show NDC the Blanc's Law procedure was able to give excellent predictions.

Jovanovic, J.V. [Institute of Physics, P.O.Box 68, 11080 Zemun, Belgrade (Serbia and Montenegro); Faculty of Mechanical Engineering, 11000 Belgrade (Serbia and Montenegro); Vrhovac, S. B. [Institute of Physics, P.O.Box 68, 11080 Zemun, Belgrade (Serbia and Montenegro)

2004-12-01T23:59:59.000Z

268

Synthesis of an un-supported, high-flow ZSM-22 zeolite membrane  

DOE Patents [OSTI]

Novel methods for synthesizing wholly un-supported, high-flow catalytic membranes consisting of 100% crystalline ZSM-22 crystals with no binder phase, having sufficient porosity to allow high Weight Hourly Space Velocities of feedstock to pass through without generating back pressure. The ZSM-22 membranes perform favorably to existing bulk ZSM-22 catalysts (e.g., via 1-butene conversion and selectivity). The method of membrane synthesis, based on Vapor Phase Transport, allows free-standing, binder-less membranes to be fabricated in varied geometries and sizes so that membranes can be tailor-made for particular geometries applications. The ZSM-22 precursor gel may be consolidated into a semi-cohesive body prior to vapor phase crystallization, for example, by uniaxial pressing. These crystalline membranes may be modified by ion exchange, pore ion exchange, framework exchange, synthesis modification techniques to incorporate other elements into the framework, such as K, H, Mg, Zn, V, Ga, and Pt.

Thoma, Steven G. (Albuquerque, NM); Nenoff, Tina M. (Albuquerque, NM)

2006-10-10T23:59:59.000Z

269

Stochastic reconstruction and electrical transport studies of porous cathode of Li-ion batteries  

E-Print Network [OSTI]

of the Li-ion batteries through developing electrode materials [1e5], reducing size [6] and optimizing shape,13], as one of the main factors limiting Li-ion battery performance, has not been resolved. Fundamental the ulti- mate performance and stability. Theoretical work of Li-ion batteries has focused on macroscopic

Liu, Fuqiang

270

Lithium Ion Transport Mechanism in Ternary Polymer Electrolyte-Ionic Liquid Mixtures - A Molecular Dynamics Simulation Study  

E-Print Network [OSTI]

The lithium transport mechanism in ternary polymer electrolytes, consisting of PEO/LiTFSI and various fractions of the ionic liquid N-methyl-N-propylpyrrolidinium bis(trifluoromethane)sulfonimide, are investigated by means of MD simulations. This is motivated by recent experimental findings [Passerini et al., Electrochim. Acta 2012, 86, 330-338], which demonstrated that these materials display an enhanced lithium mobility relative to their binary counterpart PEO/LiTFSI. In order to grasp the underlying microscopic scenario giving rise to these observations, we employ an analytical, Rouse-based cation transport model [Maitra at al., PRL 2007, 98, 227802], which has originally been devised for conventional polymer electrolytes. This model describes the cation transport via three different mechanisms, each characterized by an individual time scale. It turns out that also in the ternary electrolytes essentially all lithium ions are coordinated by PEO chains, thus ruling out a transport mechanism enhanced by the presence of ionic-liquid molecules. Rather, the plasticizing effect of the ionic liquid contributes to the increased lithium mobility by enhancing the dynamics of the PEO chains and consequently also the motion of the attached ions. Additional focus is laid on the prediction of lithium diffusion coefficients from the simulation data for various chain lengths and the comparison with experimental data, thus demonstrating the broad applicability of our approach.

Diddo Diddens; Andreas Heuer

2013-02-20T23:59:59.000Z

271

Crystal structure of a concentrative nucleoside transporter from Vibrio cholerae at 2.4;#8201;  

SciTech Connect (OSTI)

Nucleosides are required for DNA and RNA synthesis, and the nucleoside adenosine has a function in a variety of signalling processes. Transport of nucleosides across cell membranes provides the major source of nucleosides in many cell types and is also responsible for the termination of adenosine signalling. As a result of their hydrophilic nature, nucleosides require a specialized class of integral membrane proteins, known as nucleoside transporters (NTs), for specific transport across cell membranes. In addition to nucleosides, NTs are important determinants for the transport of nucleoside-derived drugs across cell membranes. A wide range of nucleoside-derived drugs, including anticancer drugs (such as Ara-C and gemcitabine) and antiviral drugs (such as zidovudine and ribavirin), have been shown to depend, at least in part, on NTs for transport across cell membranes. Concentrative nucleoside transporters, members of the solute carrier transporter superfamily SLC28, use an ion gradient in the active transport of both nucleosides and nucleoside-derived drugs against their chemical gradients. The structural basis for selective ion-coupled nucleoside transport by concentrative nucleoside transporters is unknown. Here we present the crystal structure of a concentrative nucleoside transporter from Vibrio cholerae in complex with uridine at 2.4 {angstrom}. Our functional data show that, like its human orthologues, the transporter uses a sodium-ion gradient for nucleoside transport. The structure reveals the overall architecture of this class of transporter, unravels the molecular determinants for nucleoside and sodium binding, and provides a framework for understanding the mechanism of nucleoside and nucleoside drug transport across cell membranes.

Johnson, Zachary Lee; Cheong, Cheom-Gil; Lee, Seok-Yong (Duke)

2012-07-11T23:59:59.000Z

272

Mathematical Modeling of Cation Contamination in a Proton-exchange Membrane  

SciTech Connect (OSTI)

Transport phenomena in an ion-exchange membrane containing both H+ and K+ are described using multicomponent diffusion equations (Stefan-Maxwell). A model is developed for transport through a Nafion 112 membrane in a hydrogen-pump setup. The model results are analyzed to quantify the impact of cation contamination on cell potential. It is shown that limiting current densities can result due to a decrease in proton concentration caused by the build-up of contaminant ions. An average cation concentration of 30 to 40 percent is required for appreciable effects to be noticed under typical steady-state operating conditions.

Weber, Adam; Delacourt, Charles

2008-09-11T23:59:59.000Z

273

Composite fuel cell membranes  

SciTech Connect (OSTI)

A bilayer or trilayer composite ion exchange membrane suitable for use in a fuel cell. The composite membrane has a high equivalent weight thick layer in order to provide sufficient strength and low equivalent weight surface layers for improved electrical performance in a fuel cell. In use, the composite membrane is provided with electrode surface layers. The composite membrane can be composed of a sulfonic fluoropolymer in both core and surface layers.

Plowman, Keith R. (Lake Jackson, TX); Rehg, Timothy J. (Lake Jackson, TX); Davis, Larry W. (West Columbia, TX); Carl, William P. (Marble Falls, TX); Cisar, Alan J. (Cypress, TX); Eastland, Charles S. (West Columbia, TX)

1997-01-01T23:59:59.000Z

274

Composite fuel cell membranes  

DOE Patents [OSTI]

A bilayer or trilayer composite ion exchange membrane is described suitable for use in a fuel cell. The composite membrane has a high equivalent weight thick layer in order to provide sufficient strength and low equivalent weight surface layers for improved electrical performance in a fuel cell. In use, the composite membrane is provided with electrode surface layers. The composite membrane can be composed of a sulfonic fluoropolymer in both core and surface layers.

Plowman, K.R.; Rehg, T.J.; Davis, L.W.; Carl, W.P.; Cisar, A.J.; Eastland, C.S.

1997-08-05T23:59:59.000Z

275

Temperature-Dependent Simulations of Dry Gas Transport in the Electrodes of Proton Exchange Membrane Fuel Cells  

E-Print Network [OSTI]

Membrane Fuel Cells M. J. Kermani1 J. M. Stockie2 mkermani@unb.ca stockie@unb.ca 1 Post Doctoral Fellow the cathode of a proton exchange membrane (PEM) fuel cell is studied numerically. The di usion to achieve this goal is via proton exchange mem- brane (PEM) fuel cells, which in principle combine oxygen

Stockie, John

276

OXYGEN TRANSPORT CERAMIC MEMBRANES  

SciTech Connect (OSTI)

The mechanical properties of model systems were analyzed. A reasonably accurate finite element model was implemented and a rational metric to predict the strength of ceramic/metal concentrical joints was developed. The mode of failure of the ceramic/metal joints was determined and the importance of the mechanical properties of the braze material was assessed. Thermal cycling experiments were performed on the model systems and the results were discussed. Additionally, experiments using the concept of placing diffusion barriers on the ceramic surface to limit the extent of the reaction with the braze were performed. It was also observed that the nature and morphology of the reaction zone depends greatly on the nature of the perovskite structure being used. From the experiments, it is observed that the presence of Cr in the Fe-occupied sites decreases the tendency of Fe to segregate and to precipitate out of the lattice. In these new experiments, Ni was observed to play a major role in the decomposition of the ceramic substrate.

Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

2001-05-01T23:59:59.000Z

277

OXYGEN TRANSPORT CERAMIC MEMBRANES  

SciTech Connect (OSTI)

Conversion of natural gas to liquid fuels and chemicals is a major goal for the Nation as it enters the 21st Century. Technically robust and economically viable processes are needed to capture the value of the vast reserves of natural gas on Alaska's North Slope, and wean the Nation from dependence on foreign petroleum sources. Technologies that are emerging to fulfill this need are all based syngas as an intermediate. Syngas (a mixture of hydrogen and carbon monoxide) is a fundamental building block from which chemicals and fuels can be derived. Lower cost syngas translates directly into more cost-competitive fuels and chemicals. The currently practiced commercial technology for making syngas is either steam methane reforming (SMR) or a two-step process involving cryogenic oxygen separation followed by natural gas partial oxidation (POX). These high-energy, capital-intensive processes do not always produce syngas at a cost that makes its derivatives competitive with current petroleum-based fuels and chemicals.

Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

2002-01-01T23:59:59.000Z

278

OXYGEN TRANSPORT CERAMIC MEMBRANES  

SciTech Connect (OSTI)

The mechanical properties of model systems were analyzed. A reasonably accurate finite element model was implemented and a rational metric to predict the strength of ceramic/metal concentrical joints was developed. The mode of failure of the ceramic/metal joints was determined and the importance of the mechanical properties of the braze material was assessed. Thermal cycling experiments were performed on the model systems and the results were discussed. Additionally, experiments using the concept of placing diffusion barriers on the ceramic surface to limit the extent of the reaction with the braze were performed. It was also observed that the nature and morphology of the reaction zone depends greatly on the nature of the perovskite structure being used. From the experiments, it is observed that the presence of Cr in the Fe-occupied sites decreases the tendency of Fe to segregate and to precipitate out of the lattice. In these new experiments, Ni was observed to play a major role in the decomposition of the ceramic substrate.

Dr. Sukumar Bandopadhyay; Dr. Nagendfra Nagabhushana

2001-07-01T23:59:59.000Z

279

Novel Energy Sources -Material Architecture and Charge Transport in Solid State Ionic Materials for Rechargeable Li ion Batteries  

SciTech Connect (OSTI)

Since its introduction in the consumer market at the beginning of 1990s by Sony Corporation Li-ion rechargeable battery and LiCoO2 cathode is an inseparable couple for highly reliable practical applications. However, a separation is inevitable as Li-ion rechargeable battery industry demand more and more from this well serving cathode. Spinel-type lithium manganate (e.g., LiMn2O4), lithium-based layered oxide materials (e.g., LiNiO2) and lithium-based olivine-type compounds (e.g., LiFePO4) are nowadays being extensively studied for application as alternate cathode materials in Li-ion rechargeable batteries. Primary goal of this project was the advancement of Li-ion rechargeable battery to meet the future demands of the energy sector. Major part of the research emphasized on the investigation of electrodes and solid electrolyte materials for improving the charge transport properties in Li-ion rechargeable batteries. Theoretical computational methods were used to select electrodes and electrolyte material with enhanced structural and physical properties. The effect of nano-particles on enhancing the battery performance was also examined. Satisfactory progress has been made in the bulk form and our efforts on realizing micro-battery based on thin films is close to give dividend and work is progressing well in this direction.

Katiyar, Ram S; Gmez, M; Majumder, S B; Morell, G; Tomar, M S; Smotkin, E; Bhattacharya, P; Ishikawa, Y

2009-01-19T23:59:59.000Z

280

Parametric Dependence Of Fast-ion Transport Events On The National Spherical Torus Experiment  

SciTech Connect (OSTI)

Neutral-beam heated tokamak plasmas commonly have more than one third of the plasma kinetic energy in the non-thermal energetic beam ion population. This population of fast ions heats the plasma, provides some of the current drive, and can affect the stability (positively or negatively) of magnetohydrodynamic instabilities. This population of energetic ions is not in thermodynamic equilibrium, thus there is free-energy available to drive instabilities, which may lead to redistribution of the fast ion population. Understanding under what conditions beam-driven instabilities arise, and the extent of the resulting perturbation to the fast ion population, is important for predicting and eventually demonstrating non-inductive current ramp-up and sustainment in NSTX-U, as well as the performance of future fusion plasma experiments such as ITER. This paper presents an empirical approach towards characterizing the stability boundaries for some common energetic-ion-driven instabilities seen on NSTX.

Fredrickson, Erik; Gorelenkov, N. N.; Podesta, M.; Gerhardt, S. P.; Bell, R. E.; Diallo, A.; LeBlanc, B. [Princeton Plasma Physics Lab., NJ (United States)] [Princeton Plasma Physics Lab., NJ (United States); Bortolon, A. [Univ. of Tennessee, Knoxville, TN (United States)] [Univ. of Tennessee, Knoxville, TN (United States)

2014-03-31T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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281

Transportation  

E-Print Network [OSTI]

Transportation in ancient Egypt entailed the use of boats2007 Land transport in Roman Egypt: A study of economics andDieter 1991 Building in Egypt: Pharaonic stone masonry. New

Vinson, Steve

2013-01-01T23:59:59.000Z

282

Mechanical and Transport Properties of Layer-by-Layer Electrospun Composite Proton Exchange Membranes for Fuel Cell Applications  

E-Print Network [OSTI]

Composite membranes composed of highly conductive and selective layer-by-layer (LbL) films and electrospun fiber mats were fabricated and characterized for mechanical strength and electrochemical selectivity. The LbL ...

Mannarino, Matthew M.

283

Solenoid transport of a heavy ion beam for warm dense matterstudies and inertial confinement fusion  

SciTech Connect (OSTI)

From February to July 2006, I have been doing research as a guest at Lawrence Berkeley National Laboratory (LBNL), in the Heavy Ion Fusion group. This internship, which counts as one semester in my master's program in France, I was very pleased to do it in a field that I consider has the beauty of fundamental physics, and at the same time the special appeal of a quest for a long-term and environmentally-respectful energy source. During my stay at LBNL, I have been involved in three projects, all of them related to Neutralized Drift Compression Experiment (NDCX). The first one, experimental and analytical, has consisted in measuring the effects of the eddy currents induced by the pulsed magnets in the conducting plates of the source and diagnostic chambers of the Solenoid Transport Experiment (STX, which is a subset of NDCX). We have modeled the effect and run finite-element simulations that have reproduced the perturbation to the field. Then, we have modified WARP, the Particle-In-Cell code used to model the whole experiment, in order to import realistic fields including the eddy current effects and some details of each magnet. The second project has been to take part in a campaign of WARP simulations of the same experiment to understand the leakage of electrons that was observed in the experiment as a consequence to some diagnostics and the failure of the electrostatic electron trap. The simulations have shown qualitative agreement with the measured phenomena, but are still in progress. The third project, rather theoretical, has been related to the upcoming target experiment of a thin aluminum foil heated by a beam to the 1-eV range. At the beginning I helped by analyzing simulations of the hydrodynamic expansion and cooling of the heated material. But, progressively, my work turned into making estimates for the nature of the liquid/vapor two-phase flow. In particular, I have been working on criteria and models to predict the formation of droplets, their size, and their partial or total evaporation in the expanding flow.

Armijo, Julien

2006-10-01T23:59:59.000Z

284

Momentum transport in the vicinity of q{sub min} in reverse shear tokamaks due to ion temperature gradient turbulence  

SciTech Connect (OSTI)

We present an analytic study of momentum transport of tokamak plasmas in the vicinity of minimum safety factor (q) position in reversed magnetic shear configuration. Slab ion temperature gradient modes with an equilibrium flow profile are considered in this study. Quasi-linear calculations of momentum flux clearly show the novel effects of q-curvature on the generation of intrinsic rotation and mean poloidal flow without invoking reflectional symmetry breaking of parallel wavenumber (k{sub ?}). This q-curvature effect originates from the inherent asymmetry in k{sub ?} populations with respect to a rational surface due to the quadratic proportionality of k{sub ?} when q-curvature is taken into account. Discussions are made of possible implications of q-curvature induced plasma flows on internal transport barrier formation in reversed shear tokamaks.

Singh, Rameswar, E-mail: rameswar@ipr.res.in [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India) [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Laboratoire de Physique des Plasmas, Ecole Polytechnique route de Saclay, 91128 Palaiseau Cedex (France); Singh, R [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India) [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Jhang, Hogun [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)] [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Diamond, P. H. [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of) [WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Center for Momentum Transport and Flow Organization, University of California, San Diego, California 92093 (United States); Center for Astrophysics and Space Sciences, University of California San Diego, 9500 Gilman Dr., La Jolla, California 92093-0424 (United States)

2014-01-15T23:59:59.000Z

285

Nonlinear ion concentration polarization : fundamentals and applications  

E-Print Network [OSTI]

Ion exchange membrane (IEM) is a functional material that has a permselectivity of ions. Two types of IEMs - anion exchange membrane (AEM) and cation exchange membrane (CEM) - are used in a variety of electrochemical ...

Kwak, Rhokyun

2013-01-01T23:59:59.000Z

286

Determination of Dose From Light Charged Ions Relevant to Hadron Therapy Using the Particle and Heavy Ion Transport System (PHITS)  

E-Print Network [OSTI]

on Radiation Protection (ICRP) relates Q and LET together by eqn (9). G733 Gd4c Gd5d G373G372G1e4G375G374G72eG727G736 Gd46 G374G1e4G374G375G372G372 G3beG72eG727G736G3a4 G3G3G3G1 G3G745G742G3G3G3G3G3G3 G72eG727G736G3 Gd51 G373G372G373G372 Gd4f G72eG727G736 Gd4... to note that eqn (9) is a simplified approximation made by the ICRP and although very useful to approximate Q, there are factors other than LET, such as delta ray creation, that influence Q for different ions. The effects that charged particles have...

Butkus, Michael Patrick

2011-10-21T23:59:59.000Z

287

BASELINE MEMBRANE SELECTION AND CHARACTERIZATION FOR AN SDE  

SciTech Connect (OSTI)

Thermochemical processes are being developed to provide global-scale quantities of hydrogen. A variant on sulfur-based thermochemical cycles is the Hybrid Sulfur (HyS) Process which uses a sulfur dioxide depolarized electrolyzer (SDE) to produce the hydrogen. In FY05 and FY06, testing at the Savannah River National Laboratory (SRNL) explored a low temperature fuel cell design concept for the SDE. The advantages of this design concept include high electrochemical efficiency and small footprint that are crucial for successful implementation on a commercial scale. A key component of the SDE is the ion conductive membrane through which protons produced at anode migrate to the cathode and react to produce hydrogen. An ideal membrane for the SDE should have both low ionic resistivity and low sulfur dioxide transport. These features allow the electrolyzer to perform at high currents with low potentials, along with preventing contamination of both the hydrogen output and poisoning of the catalysts involved. Another key component is the electrocatalyst material used for the anode and cathode. Good electrocatalysts should be chemically stable and have a low overpotential for the desired electrochemical reactions. This report summarizes results from activities to evaluate commercial and experimental membranes for the SDE. Several different types of commercially-available membranes were analyzed for sulfur dioxide transport as a function of acid strength including perfluorinated sulfonic acid (PFSA), sulfonated poly-etherketone-ketone, and poly-benzimidazole (PBI) membranes. Experimental membranes from the sulfonated diels-alder polyphenylenes (SDAPP) and modified Nafion{reg_sign} 117 were evaluated for SO{sub 2} transport as well. These membranes exhibited reduced transport coefficient for SO{sub 2} transport without the loss in ionic conductivity. The use of Nafion{reg_sign} with EW 1100 is recommended for the present SDE testing due to the limited data regarding chemical and mechanical stability of experimental membranes. Development of new composite membranes by incorporating metal particles or by forming multilayers between PFSA membranes and hydrocarbon membranes will provide methods that will meet the SDE targets (SO{sub 2} transport reduction by a factor of 100) while decreasing catalyst layer delamination and membrane resistivity.

Colon-Mercado, H; David Hobbs, D

2007-04-03T23:59:59.000Z

288

Phase Transition and Interpore Correlations of Water in Nanopore Membranes Georg Menzl,1  

E-Print Network [OSTI]

to electric fields, high flow rates, and rapid proton transport [1­4]. In biological systems, pro- tein pores spanning the cell membrane are filled with single-file water and regulate proton, ion, and water trans the behavior of nano- pore water. In this Letter, we use computer simulations to investigate such cooperative

Dellago, Christoph

289

IONICALLY CONDUCTING MEMBRANES FOR HYDROGEN PRODUCTION AND  

E-Print Network [OSTI]

SEQUESTRATION Oxygen Transport Membrane Hydrogen Transport Membrane Natural Gas Coal Biomass Syngas CO/H2 WGS H2 operating experience. #12;ELTRON RESEARCH INC. Syngas Production Rate ­ 60 mL/min cm2 @ 900°C Equivalent O2 Operational Experience Under High Pressure Differential SUMMARY OF ELTRON OXYGEN TRANSPORT MEMBRANE SYNGAS

290

Polyarylether composition and membrane  

DOE Patents [OSTI]

A composition including a polyarylether copolymer is provided. The copolymer includes a polyarylether backbone; and a sulfonated oligomeric group bonded to the polyarylether suitable for use as a cation conducting membrane. Method of bonding a sulfonated oligomeric group to the polyarylether backbone to form a polyarylether copolymer. The membrane may be formed from the polyarylether copolymer composition. The chain length of the sulfonated oligomeric group may be controlled to affect or control the ion conductivity of the membrane.

Hung, Joyce (Auburn, AL); Brunelle, Daniel Joseph (Burnt Hills, NY); Harmon, Marianne Elisabeth (Redondo Beach, CA); Moore, David Roger (Albany, NY); Stone, Joshua James (Worcester, NY); Zhou, Hongyi (Niskayuna, NY); Suriano, Joseph Anthony (Clifton Park, NY)

2010-11-09T23:59:59.000Z

291

Ion-modulated nonlinear electronic transport in carbon nanotube bundle/RbAg{sub 4}I{sub 5} thin film composite nanostructures  

SciTech Connect (OSTI)

We have explored the ion-modulated electronic transport properties of mixed ionic-electronic conductor (MIEC) composite nanostructures made of superionic conductor RbAg{sub 4}I{sub 5} films and carbon nanotube (CNT) bundle spiderwebs. Our experimental and theoretical studies indicate that the formation of ion-electron bound states (IEBSs) leads to strong ion-electron interference effect and interesting electronic transport of CNT, such as nonlinear current-voltage (IV) characteristics and novel temperature dependence of the current. With increasing temperature, the hybrid nanostructures show rich phases with different dependence of current on temperature, which is related to the structural phase transition of RbAg{sub 4}I{sub 5} and the transition of dissociation of IEBSs. The ion-modulation of the electric conductivity in such MIEC composite nanostructures with great tunability has been used to design new ionic-electronic composite nano-devices with function like field effect transistor.

Sun, Jia-Lin [State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084 (China); Collaborative Innovation Center of Quantum Matter, Beijing (China); Zhang, Wei, E-mail: zhang-wei@iapcm.ac.cn [Institute of Applied Physics and Computational Mathematics, P.O. Box 8009(28), Beijing 100088 (China); Wei, Jinquan [Key Laboratory for Advanced Materials Processing Technology of Education Ministry, Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Gu, Bingfu [State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084 (China)

2014-01-28T23:59:59.000Z

292

Structure and transport of aqueous electrolytes: From simple halides to radionuclide ions  

SciTech Connect (OSTI)

Molecular simulations are used to compare the structure and dynamics of conventional and radioactive aqueous electrolytes: chloride solutions with sodium, potassium, cesium, calcium, and strontium. The study of Cs{sup +} and Sr{sup 2+} is important because these radioactive ions can be extremely harmful and are often confused by living organisms for K{sup +} and Ca{sup 2+}, respectively. Na{sup +}, Ca{sup 2+}, and Sr{sup 2+} are strongly bonded to their hydration shell because of their large charge density. We find that the water molecules in the first hydration shell around Na{sup +} form hydrogen bonds between each other, whereas molecules in the first hydration shell around Ca{sup 2+} and Sr{sup 2+} predominantly form hydrogen bonds with water molecules in the second shell. In contrast to these three ions, K{sup +} and Cs{sup +} have low charge densities so that they are weakly bonded to their hydration shell. Overall, the structural differences between Ca{sup 2+} and Sr{sup 2+} are small, but the difference between their coordination numbers relative to their surface areas could potentially be used to separate these ions. Moreover, the different decays of the velocity-autocorrelation functions corresponding to these ions indicates that the difference in mass could be used to separate these cations. In this work, we also propose a new definition of the pairing time that is easy to calculate and of physical significance regardless of the problem at hand.

Hartkamp, Remco, E-mail: hartkamp@mit.edu; Coasne, Benoit, E-mail: benoit.coasne@enscm.fr [Institut Charles Gerhardt Montpellier, CNRS (UMR 5253), Universit Montpellier 2, ENSCM, 8 rue de lEcole Normale, 34296 Montpellier Cedex 05 (France); MultiScale Material Science for Energy and Environment, CNRS/MIT (UMI 3466), Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 (United States)

2014-09-28T23:59:59.000Z

293

Unique battery with a multi-functional, physicochemically active membrane separator/electrolyte-electrode monolith and a method making the same  

DOE Patents [OSTI]

The invention relates to a unique battery having a physicochemically active membrane separator/electrolyte-electrode monolith and method of making the same. The Applicant's invented battery employs a physicochemically active membrane separator/electrolyte-electrode that acts as a separator, electrolyte, and electrode, within the same monolithic structure. The chemical composition, physical arrangement of molecules, and physical geometry of the pores play a role in the sequestration and conduction of ions. In one preferred embodiment, ions are transported via the ion-hoping mechanism where the oxygens of the Al.sub.2O.sub.3 wall are available for positive ion coordination (i.e. Li.sup.+). This active membrane-electrode composite can be adjusted to a desired level of ion conductivity by manipulating the chemical composition and structure of the pore wall to either increase or decrease ion conduction.

Gerald, II, Rex E; Ruscic, Katarina J; Sears, Devin N; Smith, Luis J; Klinger, Robert J; Rathke, Jerome W

2013-11-26T23:59:59.000Z

294

Understanding extraction and beam transport in the ISIS H{sup -} Penning surface plasma ion source  

SciTech Connect (OSTI)

The ISIS H{sup -} Penning surface plasma source has been developed to produce beam currents up to 70 mA and pulse lengths up to 1.5 ms at 50 Hz. This paper details the investigation into beam extraction and beam transport in an attempt to understand the beam emittance and to try to improve the emittance. A scintillator profile measurement technique has been developed to assess the performance of different plasma electrode apertures, extraction electrode geometries, and postextraction acceleration configurations. This work shows that the present extraction, beam transport, and postacceleration system are suboptimal and further work is required to improve it.

Faircloth, D. C.; Letchford, A. P.; Gabor, C.; Whitehead, M. O.; Wood, T.; Jolly, S.; Pozimski, J.; Savage, P.; Woods, M. [STFC/RAL, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Imperial College, London SW7 2AZ (United Kingdom)

2008-02-15T23:59:59.000Z

295

The transported entropies of ions in solid state fluorides and beta-alumina  

SciTech Connect (OSTI)

The technical relevance of reversible heat effects is discussed with reference to high temperature batteries and electrolysis systems. The transported entropies of Na{sup +} in solid state mixtures of NaF and Na{sub 3}AlF{sub 6} are presented. The transported entropies are S{sup *cry}{sub Na{sup +}} = 140 {+-} 7 J K{sup {minus}1} mol{sup {minus}1} for cryolite, S{sup *NaF}{sub Na{sup +}} = 81 {+-} 8 J K{sup {minus}1} mol{sup {minus}1} for sodium fluoride and S{sup *{beta}}{sub Na{sup +}} = 60 {+-} 5 J K{sup {minus}1} mol{sup {minus}1} for sodium {beta}{double_prime}-alumina at the temperature range 380--500 C. The value obtained for sodium in the solid cryolite is higher than transported entropy of Na{sup +} in other solid sodium conductors and makes the authors predict that the transported entropy for Na{sup +} in the molten electrolyte mixture for aluminum production is substantial, and that so are the reversible heat effects in the aluminum electrolysis cell.

Sharivker, V.S.; Ratkje, S.K. [Univ. of Trondheim (Norway)

1996-10-01T23:59:59.000Z

296

Correlation between structure and electrical transport in ion-irradiated graphene grown on Cu foils  

SciTech Connect (OSTI)

Graphene grown by chemical vapor deposition and supported on SiO2 and sapphire substrates was studied following controlled introduction of defects induced by 35 keV carbon ion irradiation. Changes in Raman spectra following fluences ranging from 1012 cm-2 to 1015 cm-2 indicate that the structure of graphene evolves from a highly-ordered layer, to a patchwork of disordered domains, to an essentially amorphous film. These structural changes result in a dramatic decrease in the Hall mobility by orders of magnitude while, remarkably, the Hall concentration remains almost unchanged, suggesting that the Fermi level is pinned at a hole concentration near 1x1013 cm-2. A model for scattering by resonant scatterers is in good agreement with mobility measurements up to an ion fluence of 1x1014 cm-2.

Buchowicz, G.; Stone, P.R.; Robinson, J.T.; Cress, C.D.; Beeman, J.W.; Dubon, O.D.

2010-11-04T23:59:59.000Z

297

ENEA F. Zonca 1 Fast ion induced collective effects and resonant transport in  

E-Print Network [OSTI]

and Rutherford, PRL 34, 1428, (1975) resonant wave particle interaction of MeV ions with SA inst. due to vE vA (k vA E) 2 Experimental observation of fishbones on PDX ­ McGuire et al., PRL 50, 891, (1983) ­ fast excitation ­ Chen, White, Rosenbluth, PRL 52, 1122, (1984) Coppi, Porcelli, PRL 57, 2272, (1986) Hangzhou

Zonca, Fulvio

298

Preliminary GYRO Studies of Momentum Transport with two Ion Species R. Budny (PPPL)  

E-Print Network [OSTI]

;Electron density and q profiles for the JT60-U plasma · focus on region inside barrier and qmin PRINCETON plasma regimes 1. DIII-D L-mode pair 2. DIII-D and JET ELMy H-mode plasmas 3. JT60-U box ITB plasma (E032844) PRINCETON PLASMA PHYSICS LABORATORY PPPL 1 #12;Assumptions for new GYRO runs · 2 ion species

Budny, Robert

299

Chamber transport  

SciTech Connect (OSTI)

Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system.

OLSON,CRAIG L.

2000-05-17T23:59:59.000Z

300

Event simulations in a transport model for intermediate energy heavy ion collisions: Applications to multiplicity distributions  

E-Print Network [OSTI]

We perform transport model calculations for central collisions of mass 120 on mass 120 at laboratory beam energy in the range 20 MeV/nucleon to 200 MeV/nucleon. A simplified yet accurate method allows calculation of fluctuations in systems much larger than what was considered feasible in a well-known and already existing model. The calculations produce clusters. The distribution of clusters is remarkably similar to that obtained in equilibrium statistical model.

Mallik, S; Chaudhuri, G

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Event simulations in a transport model for intermediate energy heavy ion collisions: Applications to multiplicity distributions  

E-Print Network [OSTI]

We perform transport model calculations for central collisions of mass 120 on mass 120 at laboratory beam energy in the range 20 MeV/nucleon to 200 MeV/nucleon. A simplified yet accurate method allows calculation of fluctuations in systems much larger than what was considered feasible in a well-known and already existing model. The calculations produce clusters. The distribution of clusters is remarkably similar to that obtained in equilibrium statistical model.

S. Mallik; S. Das Gupta; G. Chaudhuri

2015-03-19T23:59:59.000Z

302

Anion exchange membrane  

DOE Patents [OSTI]

An anion exchange membrane and fuel cell incorporating the anion exchange membrane are detailed in which proazaphosphatrane and azaphosphatrane cations are covalently bonded to a sulfonated fluoropolymer support along with anionic counterions. A positive charge is dispersed in the aforementioned cations which are buried in the support to reduce the cation-anion interactions and increase the mobility of hydroxide ions, for example, across the membrane. The anion exchange membrane has the ability to operate at high temperatures and in highly alkaline environments with high conductivity and low resistance.

Verkade, John G; Wadhwa, Kuldeep; Kong, Xueqian; Schmidt-Rohr, Klaus

2013-05-07T23:59:59.000Z

303

Separation of Olefin/Paraffin Mixtures with Carrier Facilitated Membrane Final Report  

SciTech Connect (OSTI)

This document describes the results of a DOE funded joint effort of Membrane Technology and Research Inc. (MTR), SRI International (SRI), and ABB Lummus (ABB) to develop facilitated transport membranes for olefin/paraffin separations. Currently, olefin/paraffin separation is done by distillationan extremely energy-intensive process because of the low relative volatilities of olefins and paraffins. If facilitated transport membranes could be successfully commercialized, the potential energy savings achievable with this membrane technology are estimated to be 48 trillion Btu per year by the year 2020. We discovered in this work that silver salt-based facilitated transport membranes are not stable even in the presence of ideal olefin/paraffin mixtures. This decline in membrane performance appears to be caused by a previously unrecognized phenomenon that we have named olefin conditioning. As the name implies, this mechanism of performance degradation becomes operative once a membrane starts permeating olefins. This project is the first study to identify olefin conditioning as a significant factor impacting the performance of facilitated olefin transport membranes. To date, we have not identified an effective strategy to mitigate the impact of olefin conditioning. other than running at low temperatures or with low olefin feed pressures. In our opinion, this issue must be addressed before further development of facilitated olefin transport membranes can proceed. In addition to olefin conditioning, traditional carrier poisoning challenges must also be overcome. Light, hydrogen, hydrogen sulfide, and acetylene exposure adversely affect membrane performance through unwanted reaction with silver ions. Harsh poisoning tests with these species showed useful membrane lifetimes of only one week. These tests demonstrate a need to improve the stability of the olefin complexing agent to develop membranes with lifetimes satisfactory for commercial application. A successful effort to improve membrane coating solution stability resulted in the finding that membrane performance loss could be reversed for all poisoning cases except hydrogen sulfide exposure. This discovery offers the potential to extend membrane lifetime through cyclic regeneration. We also found that certain mixed carriers exhibited greater stability in reducing environments than exhibited by silver salt alone. These results offer promise that solutions to deal with carrier poisoning are possible. The main achievement of this program was the progress made in gaining a more complete understanding of the membrane stability challenges faced in the use of facilitated olefin transport membranes. Our systematic study of facilitated olefin transport uncovered the full extent of the stability challenge, including the first known identification of olefin conditioning and its impact on membrane development. We believe that significant additional fundamental research is required before facilitated olefin transport membranes are ready for industrial implementation. The best-case scenario for further development of this technology would be identification of a novel carrier that is intrinsically more stable than silver ions. If the stability problems could be largely circumvented by development of a new carrier, it would provide a clear breakthrough toward finally recognizing the potential of facilitated olefin transport. However, even if such a carrier is identified, additional development will be required to insure that the membrane matrix is a benign host for the olefin-carrier complexation reaction and shows good long-term stability.

Merkel, T.C.; Blanc, R.; Zeid, J.; Suwarlim, A.; Firat, B.; Wijmans, H.; Asaro, M. (SRI); Greene, M. (Lummus)

2007-03-12T23:59:59.000Z

304

Self-energy limited ion transport in sub-nanometer channels  

E-Print Network [OSTI]

The current-voltage characteristics of the alpha-Hemolysin protein pore during the passage of single-stranded DNA under varying ionic strength, C, are studied experimentally. We observe strong blockage of the current, weak super-linear growth of the current as a function of voltage, and a minimum of the current as a function of C. These observations are interpreted as the result of the ion electrostatic self-energy barrier originating from the large difference in the dielectric constants of water and the lipid bilayer. The dependence of DNA capture rate on C also agrees with our model.

Douwe Jan Bonthuis; Jingshan Zhang; Breton Hornblower; Jerome Mathe; Boris I. Shklovskii; Amit Meller

2006-07-19T23:59:59.000Z

305

Grafted polyelectrolyte membranes for lithium batteries and fuel cells  

E-Print Network [OSTI]

MEMBRANES FOR LITHIUM BATTERIES AND FUEL CELLS. John Kerralso be discussed. Lithium Batteries for Transportation andpolymer membrane for lithium batteries. This paper will give

Kerr, John B.

2003-01-01T23:59:59.000Z

306

Huntingtin is required for ER-to-Golgi transport and for secretory vesicle fusion at the plasma membrane  

E-Print Network [OSTI]

et al., 2009; Presley et al., 1997; Roghi and Allan, 1999). To determine whether compromising dynein activity affects the ER-to-Golgi GFP-hGH transport assay, we performed siRNA knockdown of the dynein associated intermediate chain (DIC... cells. Nature. 389:81-85. Roghi, C., and V.J. Allan. 1999. Dynamic association of cytoplasmic dynein heavy chain 1a with the Golgi apparatus and intermediate compartment. J Cell Sci. 112 ( Pt 24):4673-4685. Sahlender, D.A., R.C. Roberts, S.D. Arden...

Brandstaetter, Hemma; Kruppa, Antonina J.; Buss, Folma

2014-10-31T23:59:59.000Z

307

Research and Development of Proton-Exchange Membrane (PEM) Fuel Cell System for Transportation Applications: Initial Conceptual Design Report  

SciTech Connect (OSTI)

This report addresses Task 1.1, model development and application, and Task 1.2, vehicle mission definition. Overall intent is to produce a methanol-fueled 10-kW power source, and to evaluate electrochemical engine (ECE) use in transportation. Major achievements include development of an ECE power source model and its integration into a comprehensive power source/electric vehicle propulsion model, establishment of candidate FCV (fuel cell powered electric vehicle) mission requirements, initial FCV studies, and a candidate FCV recommendation for further study.

Not Available

1993-11-30T23:59:59.000Z

308

Transportation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassiveSubmittedStatusButler TinaContact-Information-Transmission SignTransport

309

Recent Performance of the SNS H- ion source and low-energy beam transport system  

SciTech Connect (OSTI)

Recent measurements of the H beam current show that SNS is injecting about 55 mA into the RFQ compared to 45 mA in 2010. Since 2010, the H beam exiting the RFQ dropped from 40 mA to 34 mA, which is sufficient for 1 MW of beam power. To minimize the impact of the RFQ degradation, the service cycle of the best performing source was extended to 6 weeks. The only degradation is fluctuations in the electron dump voltage towards the end of some service cycles, a problem that is being investigated. Very recently, the RFQ was retuned, which partly restored its transmission. In addition, the electrostatic low-energy beam transport system was reengineered to double its heat sinking and equipped with a thermocouple that monitors the temperature of the ground electrode between the two Einzel lenses. The recorded data show that emissions from the source at high voltage dominate the heat load. Emissions from the partly Cs-covered first lens cause the temperature to peak several hours after starting up. On rare occasions, the temperature can also peak due to corona discharges between the center ground electrode and one of the lenses.

Stockli, Martin P [ORNL] [ORNL; Ewald, Kerry D [ORNL] [ORNL; Han, Baoxi [ORNL] [ORNL; Murray Jr, S N [ORNL] [ORNL; Pennisi, Terry R [ORNL] [ORNL; Piller, Chip [ORNL] [ORNL; Santana, Manuel [ORNL] [ORNL; Tang, Johnny Y [ORNL] [ORNL; Welton, Robert F [ORNL] [ORNL

2014-01-01T23:59:59.000Z

310

Angiotensin 2 directly increases rabbit renal brush-border membrane sodium transport: Presence of local signal transduction system  

SciTech Connect (OSTI)

In the present study, the authors have examined the direct actions of angiotensin II (AII) in rabbit renal brush border membrane (BBM) where binding sites for AII exist. Addition of AII (10(-11)-10(-7) M) was found to stimulate 22Na+ uptake by the isolated BBM vesicles directly. All did not affect the Na(+)-dependent BBM glucose uptake, and the effect of AII on BBM 22Na+ uptake was inhibited by amiloride, suggesting the involvement of Na+/H+ exchange mechanism. BBM proton permeability as assessed by acridine orange quenching was not affected by AII, indicating the direct effect of AII on Na+/H+ antiport system. In search of the signal transduction mechanism, it was found that AII activated BBM phospholipase A2 (PLA) and that BBM contains a 42-kDa guanine nucleotide-binding regulatory protein (G-protein) that underwent pertussis toxin (PTX)-catalyzed ADP-ribosylation. Addition of GTP potentiated, while GDP-beta S or PTX abolished, the effects of AII on BBM PLA and 22Na+ uptake, suggesting the involvement of G-protein in AII's actions. On the other hand, inhibition of PLA by mepacrine prevented AII's effect on BBM 22Na+ uptake, and activation of PLA by mellitin or addition of arachidonic acid similarly enhanced BBM 22Na+ uptake, suggesting the role of PLA activation in mediating AII's effect on BBM 22Na+ uptake. In summary, results of the present study show a direct stimulatory effect of AII on BBM Na+/H+ antiport system, and suggest the presence of a local signal transduction system involving G-protein mediated PLA activation.

Morduchowicz, G.A.; Sheikh-Hamad, D.; Dwyer, B.E.; Stern, N.; Jo, O.D.; Yanagawa, N. (Sepulveda Veterans Administration, CA (USA))

1991-05-01T23:59:59.000Z

311

Bulk liquid membrane for the recovery of chromium(VI) from a hydrochloric acid medium using dicyclohexano-18-crown-6 as extractant-carrier  

SciTech Connect (OSTI)

The solvent extraction and transfer of chromic acid from hydrochloric acid medium through a bulk liquid membrane containing dicyclohexano-18-crown-6 (L) were studied. Extraction experiments pointed out that chromium(VI) was coextracted with the chloride ion which formed the complex ion pair L(H{sub 3}O{sup +})CrO{sub 3}Cl{sup {minus}} in the organic phase. The Donnan equilibrium isotherm based on the extraction, stripping, and CrO{sub 3}Cl{sup {minus}} hydrolysis equilibria allowed prediction of the performance of the semipermeable membrane to concentrate chlorochromic acid in the receiving phase. Transport experiments confirmed the ability of the liquid membrane to recover chlorochromic acid in pure water. The transport kinetics was modeled by using the two-film theory applied to the liquid membrane.

Zouhri, A. [Univ. Ibnou Zohr, Agadir (Morocco). Faulte de Sciences] [Univ. Ibnou Zohr, Agadir (Morocco). Faulte de Sciences; Ernst, B.; Burgard, M. [Ecole Europeenne de Chimie, Polymeres et Materiaux, Strasbourg (France)] [Ecole Europeenne de Chimie, Polymeres et Materiaux, Strasbourg (France)

1999-06-01T23:59:59.000Z

312

Battery utilizing ceramic membranes  

DOE Patents [OSTI]

A thin film battery is disclosed based on the use of ceramic membrane technology. The battery includes a pair of conductive collectors on which the materials for the anode and the cathode may be spin coated. The separator is formed of a porous metal oxide ceramic membrane impregnated with electrolyte so that electrical separation is maintained while ion mobility is also maintained. The entire battery can be made less than 10 microns thick while generating a potential in the 1 volt range.

Yahnke, Mark S. (Berkeley, CA); Shlomo, Golan (Haifa, IL); Anderson, Marc A. (Madison, WI)

1994-01-01T23:59:59.000Z

313

Ion Exclusion by Sub 2-nm Carbon Nanotube Pores  

SciTech Connect (OSTI)

Carbon nanotubes offer an outstanding platform for studying molecular transport at nanoscale, and have become promising materials for nanofluidics and membrane technology due to their unique combination of physical, chemical, mechanical, and electronic properties. In particular, both simulations and experiments have proved that fluid flow through carbon nanotubes of nanometer size diameter is exceptionally fast compared to what continuum hydrodynamic theories would predict when applied on this length scale, and also, compared to conventional membranes with pores of similar size, such as zeolites. For a variety of applications such as separation technology, molecular sensing, drug delivery, and biomimetics, selectivity is required together with fast flow. In particular, for water desalination, coupling the enhancement of the water flux with selective ion transport could drastically reduce the cost of brackish and seawater desalting. In this work, we study the ion selectivity of membranes made of aligned double-walled carbon nanotubes with sub-2 nm diameter. Negatively charged groups are introduced at the opening of the carbon nanotubes by oxygen plasma treatment. Reverse osmosis experiments coupled with capillary electrophoresis analysis of permeate and feed show significant anion and cation rejection. Ion exclusion declines by increasing ionic strength (concentration) of the feed and by lowering solution pH; also, the highest rejection is observed for the A{sub m}{sup Z{sub A}} C{sub n}{sup Z{sub C}} salts (A=anion, C=cation, z= valence) with the greatest Z{sub A}/Z{sub C} ratio. Our results strongly support a Donnan-type rejection mechanism, dominated by electrostatic interactions between fixed membrane charges and mobile ions, while steric and hydrodynamic effects appear to be less important. Comparison with commercial nanofiltration membranes for water softening reveals that our carbon nanotube membranes provides far superior water fluxes for similar ion rejection capabilities.

Fornasiero, F; Park, H G; Holt, J K; Stadermann, M; Grigoropoulos, C P; Noy, A; Bakajin, O

2008-04-09T23:59:59.000Z

314

Rapid Ammonia Gas Transport Accounts for Futile Transmembrane Cycling under NH3/NH4  

E-Print Network [OSTI]

Rapid Ammonia Gas Transport Accounts for Futile Transmembrane Cycling under NH3/NH4 + Toxicity) seedlings is predominately of the gaseous NH3 species, rather than the NH4 + ion. Influx of 13 NH3/13 NH4 + , which exceeded 200 mmol g­1 h­1 , was not commensurate with membrane depolarization or increases in root

Britto, Dev T.

315

STRUCTURAL REQUIREMENTS OF ORGANIC ANION TRANSPORTING POLYPEPTIDE MEDIATED TRANSPORT  

E-Print Network [OSTI]

The organic anion transporting polypeptides (human: OATP; other: Oatp) form a mammalian transporter superfamily that mediates the transport of structurally unrelated compounds across the cell membrane. Members in this ...

Weaver, Yi Miao

2010-04-12T23:59:59.000Z

316

OXYGEN TRANSPORT MEMBRANE (OTM) AIDED  

E-Print Network [OSTI]

· Benefits to California · Overall Technology Assessment · Appendices o Appendix A: Final Report (under · Industrial/Agricultural/Water End-Use Energy Efficiency · Renewable Energy Technologies · Environmentally

317

Diffusion through Carbon Nanotube Semipermeable membranes  

SciTech Connect (OSTI)

The goal of this project is to measure transport through CNTs and study effects of confinement at molecular scale. This work is motivated by several simulation papers in high profile journals that predict significantly higher transport rates of gases and liquids through carbon nanotubes as compared with similarly-sized nanomaterials (e.g. zeolites). The predictions are based on the effects of confinement, atomically smooth pore walls and high pore density. Our work will provide the first measurements that would compare to and hopefully validate the simulations. Gas flux is predicted to be >1000X greater for SWNTs versus zeolitesi. A high flux of 6-30 H2O/NT/ns {approx} 8-40 L/min for a 1cm{sup 2} membrane is also predicted. Neutron diffraction measurements indicate existence of a 1D water chain within a cylindrical ice sheet inside carbon nanotubes, which is consistent with the predictions of the simulation. The enabling experimental platform that we are developing is a semipermeable membrane made out of vertically aligned carbon nanotubes with gaps between nanotubes filled so that the transport occurs through the nanotubes. The major challenges of this project included: (1) Growth of CNTs in the suitable vertically aligned configuration, especially the single wall carbon nanotubes; (2) Development of a process for void-free filling gaps between CNTs; and (3) Design of the experiments that will probe the small amounts of analyte that go through. Knowledge of the behavior of water upon nanometer-scale confinement is key to understanding many biological processes. For example, the protein folding process is believed to involve water confined in a hydrophobic environment. In transmembrane proteins such as aquaporins, water transport occurs under similar conditions. And in fields as far removed as oil recovery and catalysis, an understanding of the nanoscale molecular transport occurring within the nanomaterials used (e.g. zeolites) is the key to process optimization. Furthermore, advancement of many emerging nanotechnologies in chemistry and biology will undoubtedly be aided by an understanding confined water transport, particularly the details of hydrogen bonding and solvation that become crucial on this length scale. We can envision several practical applications for our devices, including desalination, gas separations, dialysis, and semipermeable fabrics for protection against CW agents etc. The single wall carbon nanotube membranes will be the key platform for applications because they will allow high transport rates of small molecules such as water and eliminate solvated ions or CW agents.

Bakajin, O

2006-02-13T23:59:59.000Z

318

Solid-state membrane module  

DOE Patents [OSTI]

Solid-state membrane modules comprising at least one membrane unit, where the membrane unit has a dense mixed conducting oxide layer, and at least one conduit or manifold wherein the conduit or manifold comprises a dense layer and at least one of a porous layer and a slotted layer contiguous with the dense layer. The solid-state membrane modules may be used to carry out a variety of processes including the separating of any ionizable component from a feedstream wherein such ionizable component is capable of being transported through a dense mixed conducting oxide layer of the membrane units making up the membrane modules. For ease of construction, the membrane units may be planar.

Gordon, John Howard (Salt Lake City, UT); Taylor, Dale M. (Murray, UT)

2011-06-07T23:59:59.000Z

319

Space-charge compensation measurements in electron cyclotron resonance ion source low energy beam transport lines with a retarding field analyzer  

SciTech Connect (OSTI)

In this paper we describe the first systematic measurement of beam neutralization (space charge compensation) in the ECR low energy transport line with a retarding field analyzer, which can be used to measure the potential of the beam. Expected trends for the space charge compensation levels such as increase with residual gas pressure, beam current, and beam density could be observed. However, the overall levels of neutralization are consistently low (<60%). The results and the processes involved for neutralizing ion beams are discussed for conditions typical for ECR injector beam lines. The results are compared to a simple theoretical beam plasma model as well as simulations.

Winklehner, D.; Leitner, D., E-mail: leitnerd@nscl.msu.edu; Cole, D.; Machicoane, G.; Tobos, L. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)] [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

2014-02-15T23:59:59.000Z

320

Membranes, methods of making membranes, and methods of separating gases using membranes  

DOE Patents [OSTI]

Membranes, methods of making membranes, and methods of separating gases using membranes are provided. The membranes can include at least one hydrophilic polymer, at least one cross-linking agent, at least one base, and at least one amino compound. The methods of separating gases using membranes can include contacting a gas stream containing at least one of CO.sub.2, H.sub.2S, and HCl with one side of a nonporous and at least one of CO.sub.2, H.sub.2S, and HCl selectively permeable membrane such that at least one of CO.sub.2, H.sub.2S, and HCl is selectively transported through the membrane.

Ho, W. S. Winston

2012-10-02T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Folding and Function of Proteorhodopsins in Photoenergy Transducing Membranes  

SciTech Connect (OSTI)

The overall research objectives are to develop proteorhodopsin (PR) proteins as a model system for {alpha}?-helical membrane protein insertion and folding, and to advance understanding of the diversity and mechanisms of PRs, a large family of photoenergy transducers (~4000 identified) abundant in the worlds oceans. Specific aims are: (1) To develop a highefficiency genetic selection procedure for light-driven proton-pumping in E. coli cells. Such a procedure would provide a positive selection method for proper folding and function of PRs in the E. coli membrane. (2) Characterize flash-induced absorption changes and photocurrents in PR variants in organisms from various environments, and their expression level and function when expressed in E. coli. Subaims are to: (a) elucidate the relationship of the transport mechanism to mechanisms of other microbial rhodopsins, some of which like PRs function as ion transporters and some of which use light energy to activate signaling pathways (sensory rhodopsins); and (b) identify important residues and chemical events in light-driven proton transport by PRs. In addition to their importance to the energy of the biosphere PRs have attracted interest for their potential for use in making photoenergy-transducing membranes for bioengineering applications.

Spudich, John L

2012-08-10T23:59:59.000Z

322

Battery utilizing ceramic membranes  

DOE Patents [OSTI]

A thin film battery is disclosed based on the use of ceramic membrane technology. The battery includes a pair of conductive collectors on which the materials for the anode and the cathode may be spin coated. The separator is formed of a porous metal oxide ceramic membrane impregnated with electrolyte so that electrical separation is maintained while ion mobility is also maintained. The entire battery can be made less than 10 microns thick while generating a potential in the 1 volt range. 2 figs.

Yahnke, M.S.; Shlomo, G.; Anderson, M.A.

1994-08-30T23:59:59.000Z

323

Neurotransmitter Transporters  

E-Print Network [OSTI]

at specialized synaptic junctions where electrical excitability in the form of an action potential is translated membrane of neurons and glial cells. Transporters harness electrochemical gradients to force the movement.els.net #12;The response produced when a transmitter interacts with its receptors, the synaptic potential

Bergles, Dwight

324

Mean carrier transport properties and charge collection dynamics of single-crystal, natural type IIa diamonds from ion-induced conductivity measurements  

SciTech Connect (OSTI)

Ion-induced conductivity has been used to investigate the detector characteristics of diamond detectors. Both integrated-charge, and time-resolved current measurements were performed to examine the mean carrier transport properties of diamond and the dynamics of charge collection under highly-localized and high-density excitation conditions. The integrated-charge measurements were conducted with a standard pulse-counting system with {sup 241}Am radioactivity as the excitation source for the detectors. The time-resolved current measurements were performed using a 70 GHz random sampling oscilloscope with the detectors incorporated into high-speed microstrip transmission lines and the excitation source for these measurements was an ion beam of either 5-MeV He{sup +} or 10-MeV Si{sup 3+}. The detectors used in both experiments can be described as metal-semiconductor-metal (MSM) devices where a volume of the detector material is sandwiched between two metal plates. A charge collection model was developed to interpret the integrated-charge measurements which enabled estimation of the energy required to produce an electron-hole pair ({epsilon}{sub di}) and the mean carrier transport properties in diamond, such as carrier mobility and lifetime, and the behavior of the electrical contacts to diamond.

Han, S.S.

1993-09-01T23:59:59.000Z

325

A unified model of electroporation and molecular transport  

E-Print Network [OSTI]

Biological membranes form transient, conductive pores in response to elevated transmembrane voltage, a phenomenon termed electroporation. These pores facilitate electrical and molecular transport across cell membranes that ...

Smith, Kyle Christopher

2011-01-01T23:59:59.000Z

326

acid liquid membrane: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

bulk solutions of polyelectrolyte bounded by semipermeable membranes and separated by a thin film of salt-free liquid. Although the membranes are neutral, the counter-ions of the...

327

Electronic transport in Lithium Nickel Manganese Oxide, a high-voltage cathode material for Lithium-Ion batteries  

E-Print Network [OSTI]

Potential routes by which the energy densities of lithium-ion batteries may be improved abound. However, the introduction of Lithium Nickel Manganese Oxide (LixNi1i/2Mn3/2O4, or LNMO) as a positive electrode material appears ...

Ransil, Alan Patrick Adams

2013-01-01T23:59:59.000Z

328

Comparison of experimental data and three-dimensional simulations of ion beam neutralization from the Neutralized Transport Experiment  

E-Print Network [OSTI]

. Greenway, B. Logan, R. MacGill, D. Shuman et al., Phys. Rev. ST-Accel. Beams 7, 083501 2004 . Preformed-dimensional 3D particle-in-cell simulations. Along with detailed target images, 4D phase-space data with perveance,16 it is possible to scale the experi- ment to lower mass ions and particle energy as well

Gilson, Erik

329

Multicomponent membranes  

DOE Patents [OSTI]

A multicomponent membrane which may be used for separating various components which are present in a fluid feed mixture comprises a mixture of a plasticizer such as a glycol and an organic polymer cast upon a porous organic polymer support. The membrane may be prepared by casting an emulsion or a solution of the plasticizer and polymer on the porous support, evaporating the solvent and recovering the membrane after curing.

Kulprathipanja, Santi (Hoffman Estates, IL); Kulkarni, Sudhir S. (Hoffman Estates, IL); Funk, Edward W. (Highland Park, IL)

1988-01-01T23:59:59.000Z

330

Computational and experimental platform for understanding and optimizing water flux and salt rejection in nanoporous membranes.  

SciTech Connect (OSTI)

Affordable clean water is both a global and a national security issue as lack of it can cause death, disease, and international tension. Furthermore, efficient water filtration reduces the demand for energy, another national issue. The best current solution to clean water lies in reverse osmosis (RO) membranes that remove salts from water with applied pressure, but widely used polymeric membrane technology is energy intensive and produces water depleted in useful electrolytes. Furthermore incremental improvements, based on engineering solutions rather than new materials, have yielded only modest gains in performance over the last 25 years. We have pursued a creative and innovative new approach to membrane design and development for cheap desalination membranes by approaching the problem at the molecular level of pore design. Our inspiration comes from natural biological channels, which permit faster water transport than current reverse osmosis membranes and selectively pass healthy ions. Aiming for an order-of-magnitude improvement over mature polymer technology carries significant inherent risks. The success of our fundamental research effort lies in our exploiting, extending, and integrating recent advances by our team in theory, modeling, nano-fabrication and platform development. A combined theoretical and experimental platform has been developed to understand the interplay between water flux and ion rejection in precisely-defined nano-channels. Our innovative functionalization of solid state nanoporous membranes with organic protein-mimetic polymers achieves 3-fold improvement in water flux over commercial RO membranes and has yielded a pending patent and industrial interest. Our success has generated useful contributions to energy storage, nanoscience, and membrane technology research and development important for national health and prosperity.

Rempe, Susan B.

2010-09-01T23:59:59.000Z

331

The impact of energy conservation in transport models on the $\\pi^-/\\pi^+$ multiplicity ratio in heavy-ion collisions and the symmetry energy  

E-Print Network [OSTI]

The charged pion multiplicity ratio in intermediate energy central heavy-ion collisions has been proposed as a suitable observable to constrain the high density dependence of the isovector part of the equation of state, with contradicting results. Using an upgraded version of the T\\"ubingen QMD transport model, which allows the conservation of energy at a local or global level by accounting for the potential energy of hadrons in two-body collisions and leading thus to particle production threshold shifts, we demonstrate that compatible constraints for the symmetry energy stiffness can be extracted from pion multiplicity and elliptic flow observables. Nevertheless, pion multiplicities are proven to be highly sensitive to the yet unknown isovector part of the in-medium $\\Delta$(1232) potential which hinders presently the extraction of meaningful information on the high density dependence of the symmetry energy. A solution to this problem together with the inclusion of contributions presently neglected, such as ...

Cozma, M D

2014-01-01T23:59:59.000Z

332

Durable, Low-cost, Improved Fuel Cell Membranes  

SciTech Connect (OSTI)

The development of low cost, durable membranes and membranes electrode assemblies (MEAs) that operate under reduced relative humidity (RH) conditions remain a critical challenge for the successful introduction of fuel cells into mass markets. It was the goal of the team lead by Arkema, Inc. to address these shortages. Thus, this project addresses the following technical barriers from the fuel cells section of the Hydrogen Fuel Cells and Infrastructure Technologies Program Multi-Year Research, Development and Demonstration Plan: (A) Durability (B) Cost Arkemas approach consisted of using blends of polyvinylidenefluoride (PVDF) and proprietary sulfonated polyelectrolytes. In the traditional approach to polyelectrolytes for proton exchange membranes (PEM), all the required properties are packaged in one macromolecule. The properties of interest include proton conductivity, mechanical properties, durability, and water/gas transport. This is the case, for example, for perfluorosulfonic acid-containing (PFSA) membranes. However, the cost of these materials is high, largely due to the complexity and the number of steps involved in their synthesis. In addition, they suffer other shortcomings such as mediocre mechanical properties and insufficient durability for some applications. The strength and originality of Arkemas approach lies in the decoupling of ion conductivity from the other requirements. Kynar PVDF provides an exceptional combination of properties that make it ideally suited for a membrane matrix (Kynar is a registered trademark of Arkema Inc.). It exhibits outstanding chemical resistance in highly oxidative and acidic environments. In work with a prior grant, a membrane known as M41 was developed by Arkema. M41 had many of the properties needed for a high performance PEM, but had a significant deficiency in conductivity at low RH. In the first phase of this work, the processing parameters of M41 were explored as a means to increase its proton conductivity. Optimizing the processing of M41 was found to increase its proton conductivity by almost an order of magnitude at 50% RH. Characterization of the membrane morphology with Karren More at Oak Ridge National Laboratory showed that the membrane morphology was complex. This technology platform was dubbed M43 and was used as a baseline in the majority of the work on the project. Although its performance was superior to M41, M43 still showed proton conductivity an order of magnitude lower than that of a PFSA membrane at 50% RH. The MEA performance of M43 could be increased by reducing the thickness from 1 to 0.6 mils. However, the performance of the thinner M43 still did not match that of a PFSA membrane.

Chris Roger; David Mountz; Wensheng He; Tao Zhang

2011-03-17T23:59:59.000Z

333

Commentary on A Conceptual Design of Transport Lines for a Heavy-Ion Inertial-Fusion Power Plant  

SciTech Connect (OSTI)

Some major system features are not stated but can be inferred. For example this is probably an engineering test facility, not a power plant driver, because the standoff from target to final magnet is only 5.0 m. The fusion target takes two-sided illumination with indirect drive using a total of 60 beam pulses: 10 pre-pulses (3.0 GeV) + 20 main pulses (4.0 GeV) from each side. On page 12 it's stated that the charge per beam pulse is 26.8 {micro}C, so we calculate pre-pulse: 20 x 3 GeV x 26.8 {micro}C = 1.608MJ, main pulse: 40 x 4 GeV x 26.8 {micro}C = 4.288MJ, total beam energy 5.896MJ. The beam ion mass ks 200 amu, so the species is Hg{sup +}. Therefore the mid-pulse velocities are: pre-pulse v = .1773c = 5.316 x 10{sup 7} m/s, main pulse v = .2040c = 6.114 x 10{sup 7} m/s, On page 12 it is stated that the pre-compression pulse length is L{sub 0} = 10.0m, and compression is by a 'factor of order 20'. They infer a final pulse length of about .5 m and final durations pre-pulse {tau} {approx} .5/5.316 x 10{sup 7} = 9.4 ns; main pulse {tau} {approx} .5/6.114 x 10{sup 7} = 8.2 ms. The magnetic rigidity of the beam ions is [B{rho}] = {gamma}m v/e = {l_brace} 112.0 T-m - prepulse/129.5 T-m - mainpulse{r_brace}.

Lee, E.P.

2011-04-13T23:59:59.000Z

334

Single nanopore transport of synthetic and biological polyelectrolytes in three-dimensional hybrid microfluidic/nanofluidic devices  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

This paper presents a study of electrokinetic transport in single nanopores integrated into vertically-stacked three-dimensional hybrid microfluidic/nanofluidic structures. In these devices single nanopores, created by focused ion beam (FIB) milling in thin polymer films, provide fluidic connection between two vertically separated, perpendicular microfluidic channels. Experiments address both systems in which the nanoporous membrane is composed of the same (homojunction) or different (heterojunction) polymer as the microfluidic channels. These devices are then used to study the electrokinetic transport properties of synthetic (i.e., polystyrene sulfonate and polyallylamine) and biological (i.e.,DNA) polyelectrolytes across these nanopores. Single nanopore transport of polyelectrolytes across these nanopores using both electrical current measurements and confocal microscopy. Both optical and electrical measurements indicate that electroosmotic transport is predominant over electrophoresis in single nanopores with d > 180 nm, consistent with results obtained under similar conditions for nanocapillary array membranes.

King, Travis L. [Univ. of Illinois at Urbana-Champaign, IL (United States). Department of Chemistry; Gatimu, Enid N.; Bohn, Paul W.

2009-01-02T23:59:59.000Z

335

The influence of oscillating electromagnetic fields on membrane structure and function: Synthetic liposome and natural membrane bilayer systems with direct application to the controlled delivery of chemical agents  

SciTech Connect (OSTI)

Investigations have been conducted to determine if an imposed electromagnetic field can influence membrane transport, and ion and drug permeability in both synthetic and natural cell membrane systems. Microwave fields enhance accumulation of sodium in the lymphocyte and induce protein shedding at Tc. Microwaves also trigger membrane permeability of liposome systems under specific field exposure conditions. Sensitivity varies in a defined way in bilayers displaying a membrane structural phase transition temperature, Tc; maximal release was observed at or near Tc. Significantly, liposome systems without a membrane phase transition were also found to experience permeability increases but, in contrast, this response was temperature independent. The above results indicate that field-enhanced drug release occurs in liposome vesicles that possess a Tc as well as non-Tc liposomes. Additional studies extend non-Tc liposome responses to the in vivo case in which microwaves trigger Gentamicin release from a liposome depot'' placed subcutaneously in the rat hind leg. In addition, evidence is provided that cell surface sequestered liposomes can be triggered by microwave fields to release drugs directly into target cells. 24 refs., 6 figs.

Liburdy, R.P.; de Manincor, D.; Fingado, B.

1989-09-01T23:59:59.000Z

336

FY08 MEMBRANE CHARACTERIZATION REPORT FOR HYBRID SULFUR ELECTROLYZER  

SciTech Connect (OSTI)

This report summarizes results from all of the membrane testing completed to date at the Savannah River National Laboratory (SRNL) for the sulfur dioxide-depolarized electrolyzer (SDE). Several types of commercially-available membranes have been analyzed for ionic resistance and sulfur dioxide transport including perfluorinated sulfonic acid (PFSA), sulfonated polyether-ketone-ketone (SPEKK), and polybenzimidazole membranes (PBI). Of these membrane types, the poly-benzimidazole membrane, Celtec-L, exhibited the best combination of characteristics for use in an SDE. Several experimental membranes have also been analyzed including hydrated sulfonated Diels-Alder polyphenylenes (SDAPP) membranes from Sandia National Laboratory, perfluorosulfonimide (PFSI) and sulfonated perfluorocyclobutyl aromatic ether (S-PFCB) prepared by Clemson University, hydrated platinum-treated PFSA prepared by Giner Electrochemical Systems (GES) and Pt-Nafion{reg_sign} 115 composites prepared at SRNL. The chemical stability, SO{sub 2} transport and ionic conductivity characteristics have been measured for several commercially available and experimental proton-conducting membranes. Commercially available PFSA membranes such as the Nafion{reg_sign} series exhibited excellent chemical stability and ionic conductivity in sulfur dioxide saturated sulfuric acid solutions. Sulfur dioxide transport in the Nafion{reg_sign} membranes varied proportionally with the thickness and equivalent weight of the membrane. Although the SO{sub 2} transport in the Nafion{reg_sign} membranes is higher than desired, the excellent chemical stability and conductivity makes this membrane the best commercially-available membrane at this time. Initial results indicated that a modified Nafion{reg_sign} membrane incorporating Pt nanoparticles exhibited significantly reduced SO{sub 2} transport. Reduced SO{sub 2} transport was also measured with commercially available PBI membrane and several experimental membranes produced at SNL and Clemson. These membranes also exhibit good chemical stability and conductivity in concentrated sulfuric acid solutions and, thus, serve as promising candidates for the SDE. Therefore, we recommend further testing of these membranes including electrolyzer testing to determine if the reduced SO{sub 2} transport eliminates the formation of sulfur-containing films at the membrane/cathode interface. SO{sub 2} transport measurements in the custom built characterization cell identified experimental limitations of the original design. During the last quarter of FY08 we redesigned and fabricated a new testing cell to overcome the previous limitations. This cell also offers the capability to test membranes under polarized conditions as well as test the performance of MEAs under selected electrolyzer conditions.

Hobbs, D; Hector Colon-Mercado, H; Mark Elvington, M

2008-09-01T23:59:59.000Z

337

New Proton-Ionizable, Calixarene-Based Ligands for Selective Metal Ion Separations  

SciTech Connect (OSTI)

The project objective was the discovery of new ligands for performing metal ion separations. The research effort entailed the preparation of new metal ion complexing agents and polymers and their evaluation in metal ion separation processes of solvent extraction, synthetic liquid membrane transport, and sorption. Structural variations in acyclic, cyclic, and bicyclic organic ligands were used to probe their influence upon the efficiency and selectivity with which metal ion separations can be performed. A unifying feature of the ligand structures is the presence of one (or more) side arm with a pendent acidic function. When a metal ion is complexed within the central cavity of the ligand, ionization of the side arm(s) produces the requisite anion(s) for formation of an overall electroneutral complex. This markedly enhances extraction/transport efficiency for separations in which movement of aqueous phase anions of chloride, nitrate, or sulfate into an organic medium would be required. Through systematic structural variations, new ligands have been developed for efficient and selective separations of monovalent metal ions (e.g., alkali metal, silver, and thallium cations) and of divalent metal ion species (e.g., alkaline earth metal, lead, and mercury cations). Research results obtained in these fundamental investigations provide important insight for the design and development of ligands suitable for practical metal ion separation applications.

Bartsch, Richard A.

2012-06-04T23:59:59.000Z

338

Enhancement of the helium resonance lines in the solar atmosphere by suprathermal electron excitation I: non-thermal transport of helium ions  

E-Print Network [OSTI]

Models of the solar transition region made from lines other than those of helium cannot account for the strength of the helium lines. However, the collisional excitation rates of the helium resonance lines are unusually sensitive to the energy of the exciting electrons. Non-thermal motions in the transition region could drive slowly-ionizing helium ions rapidly through the steep temperature gradient, exposing them to excitation by electrons characteristic of higher temperatures than those describing their ionization state. We present the results of calculations which use a more physical representation of the lifetimes of the ground states of He I and He II than was adopted in earlier work on this process. New emission measure distributions are used to calculate the temperature variation with height. The results show that non-thermal motions can lead to enhancements of the He I and He II resonance line intensities by factors that are comparable with those required. Excitation by non-Maxwellian electron distributions would reduce the effects of non-thermal transport. The effects of non-thermal motions are more consistent with the observed spatial distribution of helium emission than are those of excitation by non-Maxwellian electron distributions alone. In particular, they account better for the observed line intensity ratio I(537.0 A)/I(584.3 A), and its variation with location.

G. R. Smith; C. Jordan

2002-08-16T23:59:59.000Z

339

The impact of energy conservation in transport models on the $?^-/?^+$ multiplicity ratio in heavy-ion collisions and the symmetry energy  

E-Print Network [OSTI]

The charged pion multiplicity ratio in intermediate energy central heavy-ion collisions has been proposed as a suitable observable to constrain the high density dependence of the isovector part of the equation of state, with contradicting results. Using an upgraded version of the T\\"ubingen QMD transport model, which allows the conservation of energy at a local or global level by accounting for the potential energy of hadrons in two-body collisions and leading thus to particle production threshold shifts, we demonstrate that compatible constraints for the symmetry energy stiffness can be extracted from pion multiplicity and elliptic flow observables. Nevertheless, pion multiplicities are proven to be highly sensitive to the yet unknown isovector part of the in-medium $\\Delta$(1232) potential which hinders presently the extraction of meaningful information on the high density dependence of the symmetry energy. A solution to this problem together with the inclusion of contributions presently neglected, such as in-medium pion potentials and retardation effects, are needed for a final verdict on this topic.

M. D. Cozma

2014-09-10T23:59:59.000Z

340

COMBUSTION-ASSISTED CO2 CAPTURE USING MECC MEMBRANES  

SciTech Connect (OSTI)

Mixed Electron and Carbonate ion Conductor (MECC) membranes have been proposed as a means to separate CO{sub 2} from power plant flue gas. Here a modified MECC CO{sub 2} capture process is analyzed that supplements retentate pressurization and permeate evacuation as a means to create a CO{sub 2} driving force with a process assisted by the catalytic combustion of syngas on the permeate side of the membrane. The combustion reactions consume transported oxygen, making it unavailable for the backwards transport reaction. With this change, the MECC capture system becomes exothermic, and steam for electricity production may be generated from the waste heat. Greater than 90% of the CO{sub 2} in the flue gas may be captured, and a compressed CO{sub 2} product stream is produced. A fossil-fueled power plant using this process would consume 14% more fuel per unit electricity produced than a power plant with no CO{sub 2} capture system, and has the potential to meet U.S. DOE's goal that deployment of a CO{sub 2} capture system at a fossil-fueled power plant should not increase the cost of electricity from the combined facility by more than 30%.

Brinkman, K.; Gray, J.

2012-03-30T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
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341

Combustion-Assisted CO2 Capture Using MECC Membranes  

SciTech Connect (OSTI)

Mixed Electron and Carbonate ion Conductor (MECC) membranes have been proposed as a means to separate CO2 from power plant flue gas. Here a modified MECC CO2 capture process is analyzed that supplements retentate pressurization and permeate evacuation as a means to create a CO2 driving force with a process assisted by the catalytic combustion of syngas on the permeate side of the membrane. The combustion reactions consume transported oxygen, making it unavailable for the backwards transport reaction. With this change, the MECC capture system becomes exothermic, and steam for electricity production may be generated from the waste heat. Greater than 90% of the CO2 in the flue gas may be captured, and a compressed CO2 product stream is produced. A fossil-fueled power plant using this process would consume 14% more fuel per unit electricity produced than a power plant with no CO2 capture system, and has the potential to meet U.S. DOE s goal that deployment of a CO2 capture system at a fossil-fueled power plant should not increase the cost of electricity from the combined facility by more than 30%.

Sherman, Steven R [ORNL; Gray, Dr. Joshua R. [Savannah River National Laboratory (SRNL), Aiken, S.C.; Brinkman, Dr. Kyle S. [Savannah River National Laboratory (SRNL), Aiken, S.C.; Huang, Dr. Kevin [University of South Carolina, Columbia

2012-01-01T23:59:59.000Z

342

Effect of bound state of water on hydronium ion mobility in hydrated Nafion using molecular dynamics simulations  

SciTech Connect (OSTI)

We have performed a detailed analysis of the structural properties of the sulfonate groups in terms of isolated and overlapped solvation shells in the nanostructure of hydrated Nafion membrane using classical molecular dynamics simulations. Our simulations have demonstrated the correlation between the two different areas in bound water region, i.e., the first solvation shell, and the vehicular transport of hydronium ions at different water contents. We have employed a model of the Nafion membrane using the improved force field, which is newly modified and validated by comparing the density and water diffusivity with those obtained experimentally. The first solvation shells were classified into the two types, the isolated area and the overlapped area. The mean residence times of solvent molecules explicitly showed the different behaviors in each of those areas in terms of the vehicular transport of protons: the diffusivity of classical hydronium ions in the overlapped area dominates their total diffusion at lower water contents while that in the isolated area dominates for their diffusion at higher water contents. The results provided insights into the importance role of those areas in the solvation shells for the diffusivity of vehicular transport of hydronium ions in hydrated Nafion membrane.

Mabuchi, Takuya, E-mail: mabuchi@nanoint.ifs.tohoku.ac.jp [Graduate School of Engineering, Tohoku University, Sendai, Miyagi 980-8577 (Japan); Tokumasu, Takashi [Institute of Fluid Science, Tohoku University, Sendai, Miyagi 980-8577 (Japan)

2014-09-14T23:59:59.000Z

343

Dual Phase Membrane for High Temperature CO2 Separation  

SciTech Connect (OSTI)

This project aimed at synthesis of a new inorganic dual-phase carbonate membrane for high temperature CO{sub 2} separation. Metal-carbonate dual-phase membranes were prepared by the direct infiltration method and the synthesis conditions were optimized. Permeation tests for CO{sub 2} and N{sub 2} from 450-750 C showed very low permeances of those two gases through the dual-phase membrane, which was expected due to the lack of ionization of those two particular gases. Permeance of the CO{sub 2} and O{sub 2} mixture was much higher, indicating that the gases do form an ionic species, CO{sub 3}{sup 2-}, enhancing transport through the membrane. However, at temperatures in excess of 650 C, the permeance of CO{sub 3}{sup 2-} decreased rapidly, while predictions showed that permeance should have continued to increase with temperature. XRD data obtained from used membrane indicated that lithium iron oxides formed on the support surface. This lithium iron oxide layer has a very low conductivity, which drastically reduces the flow of electrons to the CO{sub 2}/O{sub 2} gas mixture; thus limiting the formation of the ionic species required for transport through the membrane. These results indicated that the use of stainless steel supports in a high temperature oxidative environment can lead to decreased performance of the membranes. This revelation created the need for an oxidation resistant support, which could be gained by the use of a ceramic-type membrane. Work was extended to synthesize a new inorganic dual-phase carbonate membrane for high temperature CO{sub 2} separation. Helium permeance of the support before and after infiltration of molten carbonate are on the order of 10{sup -6} and 10{sup -10} moles/m{sup 2} {center_dot} Pa {center_dot} s respectively, indicating that the molten carbonate is able to sufficiently infiltrate the membrane. It was found that La{sub 0.6}Sr{sub 0.4}Co{sub 0.8}Fe{sub 0.2}O{sub 3-{delta}} (LSCF) was a suitable candidate for the support material. This support material proved to separate CO{sub 2} when combined with O{sub 2} at a flux of 0.194 ml/min {center_dot} cm{sup 2} at 850 C. It was also observed that, because LSCF is a mixed conductor (conductor of both electrons and oxygen ions), the support was able to provide its own oxygen to facilitate separation of CO{sub 2}. Without feeding O{sub 2}, the LSCF dual phase membrane produced a maximum CO{sub 2} flux of 0.246 ml/min {center_dot} cm{sup 2} at 900 C.

Jerry Lin

2007-06-30T23:59:59.000Z

344

This article was downloaded by:[Smith, Bradley] [Smith, Bradley  

E-Print Network [OSTI]

. Keywords: Membrane transport; Ionosphere; Ion channel; Mobile carrier; Membrane pore; Self the permeability of small polar molecules and inorganic ions. Controlled ion transport across membranes and W. Matthew Leevy , 'Recent Advances in Synthetic Membrane Transporters', Supramolecular Chemistry

Smith, Bradley D.

345

Fuel cell water transport  

DOE Patents [OSTI]

The moisture content and temperature of hydrogen and oxygen gases is regulated throughout traverse of the gases in a fuel cell incorporating a solid polymer membrane. At least one of the gases traverses a first flow field adjacent the solid polymer membrane, where chemical reactions occur to generate an electrical current. A second flow field is located sequential with the first flow field and incorporates a membrane for effective water transport. A control fluid is then circulated adjacent the second membrane on the face opposite the fuel cell gas wherein moisture is either transported from the control fluid to humidify a fuel gas, e.g., hydrogen, or to the control fluid to prevent excess water buildup in the oxidizer gas, e.g., oxygen. Evaporation of water into the control gas and the control gas temperature act to control the fuel cell gas temperatures throughout the traverse of the fuel cell by the gases.

Vanderborgh, Nicholas E. (Los Alamos, NM); Hedstrom, James C. (Los Alamos, NM)

1990-01-01T23:59:59.000Z

346

Solid state proton and electron mediating membrane and use in catalytic membrane reactors  

DOE Patents [OSTI]

This invention provides catalytic proton and electron mediating membranes useful in catalytic reactors. The membranes have an oxidation and a reduction surface and comprise a single-phase mixed metal oxide material of the formula: AB{sub 1{minus}x}B{prime}{sub x}O{sub 3{minus}y} wherein A is selected from Ca, Sr or Ba ions; B is selected from Ce, Tb, Pr, or Th ions; B{prime} is selected from Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Al, Ga, or In ions, or combinations thereof; and x is greater than or equal to 0.02 and less than or equal to 0.5. The membranes can further comprise a catalyst on either the oxidation or reduction surface, or both. Membranes include those which are fabricated by combining powders of metal oxides or metal carbonates of metal A ion, metal B ion and metal B{prime} ion such that the stoichiometric ratio A:B:B{prime} is 1:1{minus}x:x where 0.2{<=}{times}0.5, repeatedly calcining and milling the combined powders until a single-phase material is obtained and pressing and sintering the single phase material to obtain a membrane. 6 figs.

White, J.H.; Schwartz, M.; Sammells, A.F.

1998-10-13T23:59:59.000Z

347

Parametic Study of the current limit within a single driver-scale transport beam line of an induction Linac for Heavy Ion Fusion  

E-Print Network [OSTI]

to controlled thermonuclear fusion which uses intense ion orto controlled thermonuclear fusion energy to commercialFusion Energy (MFE) is the approach to controlled thermonuclear

Prost, Lionel Robert

2007-01-01T23:59:59.000Z

348

E-Print Network 3.0 - abc transporter mutants Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

THE ABC TRANSPORTER SUPERFAMILY Summary: -association of point mutants. 1. Introduction ATP-binding cassette (ABC) transporters are membrane-spanning proteins... -associated...

349

Computationally Efficient Strategy for Modeling the Effect of Ion ...  

E-Print Network [OSTI]

currents that flow through a variety of types of ion channels control the membrane potential to generate the rich dynamics that are observed in cells [2].

-

2007-03-14T23:59:59.000Z

350

Lithium Source For High Performance Li-ion Cells  

Broader source: Energy.gov (indexed) [DOE]

New cathode and anode electrodes are required to improve the energy density of Li-ion cells for transportation technologies. The cost of Li-ion systems for transportation...

351

Acidic Ion Exchange Membrane - Energy Innovation Portal  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout the Building Technologies OfficeAccounting forFacilities

352

Alternate Fuel Cell Membranes for Energy Independence  

SciTech Connect (OSTI)

The overall objective of this project was the development and evaluation of novel hydrocarbon fuel cell (FC) membranes that possess high temperature performance and long term chemical/mechanical durability in proton exchange membrane (PEM) fuel cells (FC). The major research theme was synthesis of aromatic hydrocarbon polymers of the poly(arylene ether sulfone) (PAES) type containing sulfonic acid groups tethered to the backbone via perfluorinated alkylene linkages and in some cases also directly attached to the phenylene groups along the backbone. Other research themes were the use of nitrogen-based heterocyclics instead of acid groups for proton conduction, which provides high temperature, low relative humidity membranes with high mechanical/thermal/chemical stability and pendant moieties that exhibit high proton conductivities in the absence of water, and synthesis of block copolymers consisting of a proton conducting block coupled to poly(perfluorinated propylene oxide) (PFPO) blocks. Accomplishments of the project were as follows: 1) establishment of a vertically integrated program of synthesis, characterization, and evaluation of FC membranes, 2) establishment of benchmark membrane performance data based on Nafion for comparison to experimental membrane performance, 3) development of a new perfluoroalkyl sulfonate monomer, N,N-diisopropylethylammonium 2,2-bis(p-hydroxyphenyl) pentafluoropropanesulfonate (HPPS), 4) synthesis of random and block copolymer membranes from HPPS, 5) synthesis of block copolymer membranes containing high-acid-concentration hydrophilic blocks consisting of HPPS and 3,3'-disulfonate-4,4'-dichlorodiphenylsulfone (sDCDPS), 6) development of synthetic routes to aromatic polymer backbones containing pendent 1H-1,2,3-triazole moieties, 7) development of coupling strategies to create phase-separated block copolymers between hydrophilic sulfonated prepolymers and commodity polymers such as PFPO, 8) establishment of basic performance properties of experimental membranes, 9) fabrication and FC performance testing of membrane electrode assemblies (MEA) from experimental membranes, and 10) measurement of ex situ and in situ membrane durability of experimental membranes. Although none of the experimental hydrocarbon membranes that issued from the project displayed proton conductivities that met DOE requirements, the project contributed to our basic understanding of membrane structure-property relationships in a number of key respects. An important finding of the benchmark studies is that physical degradation associated with humidity and temperature variations in the FC tend to open new fuel crossover pathways and act synergistically with chemical degradation to accelerate overall membrane degradation. Thus, for long term membrane survival and efficient fuel utilization, membranes must withstand internal stresses due to humidity and temperature changes. In this respect, rigid aromatic hydrocarbon fuel cell membranes, e.g. PAES, offer an advantage over un-modified Nafion membranes. The benchmark studies also showed that broadband dielectric spectroscopy is a potentially powerful tool in assessing shifts in the fundamental macromolecular dynamics caused by Nafion chemical degradation, and thus, this technique is of relevance in interrogating proton exchange membrane durability in fuel cells and macromolecular dynamics as coupled to proton migration, which is of fundamental relevance in proton exchange membranes in fuel cells. A key finding from the hydrocarbon membrane synthesis effort was that rigid aromatic polymers containing isolated ion exchange groups tethered tightly to the backbone (short tether), such as HPPS, provide excellent mechanical and durability properties but do not provide sufficient conductivity, in either random or block configuration, when used as the sole ion exchange monomer. However, we continue to hypothesize that longer tethers, and tethered groups spaced more closely within the hydrophilic chain elements of the polymer, will yield highly conductive materials with excellent mech

Storey, Robson, F.; Mauritz, Kenneth, A.; Patton, Derek, L.; Savin, Daniel, A.

2012-12-18T23:59:59.000Z

353

Membranes for corrosive oxidations. Final CRADA report.  

SciTech Connect (OSTI)

The objective of this project is to develop porous hydrophilic membranes that are highly resistant to oxidative and corrosive conditions and to deploy them for recovery and purification of high tonnage chemicals such as hydrogen peroxide and other oxychemicals. The research team patented a process for membrane-based separation of hydrogen peroxide (US Patent No. 5,662,878). The process is based on using a hydrophilic membrane to separate hydrogen peroxide from the organic working solution. To enable this process, a new method for producing hydrophilic membrane materials (Patent No.6,464,880) was reported. We investigated methods of producing these hydrophilic materials and evaluated separations performance in comparison to membrane stability. It was determined that at the required membrane flux, membrane stability was not sufficient to design a commercial process. This work was published (Hestekin et al., J. Membrane Science 2006). To meet the performance needs of the process, we developed a membrane contactor method to extract the hydrogen peroxide, then we surveyed several commercial and pre-commercial membrane materials. We identified pre-commercial hydrophilic membranes with the required selectivity, flux, and stability to meet the needs of the process. In addition, we invented a novel reaction/separations format that greatly increases the performance of the process. To test the performance of the membranes and the new formats we procured and integrated reactor/membrane separations unit that enables controlled mixing, flow, temperature control, pressure control, and sampling. The results were used to file a US non-provisional patent application (ANL-INV 03-12). Hydrogen peroxide is widely used in pulp and paper applications, environmental treatment, and other industries. Virtually all hydrogen peroxide production is now based on a process featuring catalytic hydrogenation followed by auto-oxidation of suitable organic carrier molecules. This process has several drawbacks, particularly in the extraction phase. One general disadvantage of this technology is that hydrogen peroxide must be produced at large centralized plants where it is concentrated to 70% by distillation and transported to the users plant sites where it is diluted before use. Advanced membranes have the potential to enable more efficient, economic, and safe manufacture of hydrogen peroxide. Advanced membrane technology would allow filtration-based separation to replace the difficult liquid-liquid extraction based separation step of the hydrogen peroxide process. This would make it possible for hydrogen peroxide to be produced on-site in mini-plants at 30% concentration and used at the same plant location without distillation and transportation. As a result, production could become more cost-effective, safe and energy efficient.

Snyder, S. W.; Energy Systems

2010-02-01T23:59:59.000Z

354

Microcomposite Fuel Cell Membranes  

Broader source: Energy.gov [DOE]

Summary of microcomposite fuel cell membrane work presented to the High Temperature Membrane Working Group Meeting, Orlando FL, October 17, 2003

355

E-Print Network 3.0 - anion selective membrane Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

potential... Development of synthetic membrane transporters for anions ... Source: Smith, Bradley D. - Department of Chemistry and Biochemistry, University of Notre Dame...

356

Solution dewatering with concomitant ion removal  

DOE Patents [OSTI]

One of the biggest needs in the separations and waste handling and reduction area is a method for dewatering ion-containing solutions. Unexpectedly, it has been found that phosphazene polymers can discriminate between water and metal ions, allowing water to pass through the membrane while retaining the ions. This unexpected result, along with the inherent chemical and thermal stability of the phosphazene polymers, yields a powerful tool for separating and dewatering metal-ion-containing solutions.

Peterson, Eric S.; Marshall, Douglas W.; Stone, Mark L.

2003-08-05T23:59:59.000Z

357

Self-Induced Docking Site of a Deeply Embedded Peripheral Membrane Protein  

E-Print Network [OSTI]

paramagnetic resonance (EPR). Noting that in the membrane-bound state the three calcium binding loops features: an eight-strand antiparallel b-sandwich, and three negatively charged calcium-binding loops (CBLs are complexed to two calcium ions, we initially restrained the calcium ions at the membrane depth determined

White, Stephen

358

A Mechanistic Study of Chemically Modified Inorganic Membranes for Gas and Liquid Separations  

SciTech Connect (OSTI)

This final report will summarize the progress made during the period August 1, 1993 - October 31, 2010 with support from DOE grant number DE-FG03-93ER14363. The objectives of the research have been to investigate the transport mechanisms in micro- and mesoporous, metal oxide membranes and to examine the relationship between the microstructure of the membrane, the membrane surface chemistry, and the separation performance of the membrane. Examples of the membrane materials under investigation are the microporous silica hollow fiber membrane manufactured by PPG Industries, chemically modified mesoporous oxide membranes, and polymer membranes containing microporous oxides (mixed matrix membranes). Analytical techniques such as NMR, FTIR and Raman spectroscopy, thermal analysis, and gas adsorption were used to investigate membrane microstructure and to probe the chemical interactions occurring at the gas-membrane interface.

Way, J Douglas

2011-01-21T23:59:59.000Z

359

Membrane fluids and Dirac membrane fluids  

E-Print Network [OSTI]

There are two different methods to describe membrane (string) fluids, which use different field content. The relation between the methods is clarified by construction of combined method. Dirac membrane field appears naturally in new approach. It provides a possibility to consider new aspects of electrodynamics-type theories with electric and magnetic sources. The membrane fluid models automatically prohibit simulatenos existence of electric and magnetic currents. Possible applications to the dark energy problem are mentioned.

M. G. Ivanov

2005-05-04T23:59:59.000Z

360

Nanofiltration of Electrolyte Solutions by Sub-2nm Carbon Nanotube Membranes  

SciTech Connect (OSTI)

Both MD simulations and experimental studies have shown that liquid and gas flow through carbon nanotubes with nanometer size diameter is exceptionally fast. For applications in separation technology, selectivity is required together with fast flow. In this work, we use pressure-driven filtration experiments to study ion exclusion in silicon nitride/sub-2-nm CNT composite membranes as a function of solution ionic strength, pH, and ion valence. We show that carbon nanotube membranes exhibit significant ion exclusion at low salt concentration. Our results support a rejection mechanism dominated by electrostatic interactions between fixed membrane charges and mobile ions, while steric and hydrodynamic effects appear to be less important. Comparison with commercial nanofiltration membranes for water softening reveals that our carbon nanotube membranes provides far superior water fluxes for similar ion rejection capabilities.

Fornasiero, F; Park, H G; Holt, J K; Stadermann, M; Kim, S; In, J B; Grigoropoulos, C P; Noy, A; Bakajin, O

2008-03-13T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Corrugated Membrane Fuel Cell Structures  

SciTech Connect (OSTI)

One of the most challenging aspects of traditional PEM fuel cell stacks is the difficulty achieving the platinum catalyst utilization target of 0.2 gPt/kWe set forth by the DOE. Good catalyst utilization can be achieved with state-of-the-art catalyst coated membranes (CCM) when low catalyst loadings (<0.3 mg/cm2) are used at a low current. However, when low platinum loadings are used, the peak power density is lower than conventional loadings, requiring a larger total active area and a larger bipolar plate. This results in a lower overall stack power density not meeting the DOE target. By corrugating the fuel cell membrane electrode structure, Ion Power?s goal is to realize both the Pt utilization targets as well as the power density targets of the DOE. This will be achieved by demonstrating a fuel cell single cell (50 cm2) with a twofold increase in the membrane active area over the geometric area of the cell by corrugating the MEA structure. The corrugating structure must be able to demonstrate the target properties of < 10 mOhm-cm2 electrical resistance at > 20 psi compressive strength over the active area, in combination with offering at least 80% of power density that can be achieved by using the same MEA in a flat plate structure. Corrugated membrane fuel cell structures also have the potential to meet DOE power density targets by essentially packaging more membrane area into the same fuel cell volume as compared to conventional stack constructions.

Grot, Stephen [President, Ion Power Inc.] President, Ion Power Inc.

2013-09-30T23:59:59.000Z

362

Nanoporous Polytetrafluoroethylene/Silica Composite Separator as a High-Performance All-Vanadium Redox Flow Battery Membrane  

SciTech Connect (OSTI)

Driven by the motivation of searching for low-cost membrane alternatives, a novel nanoporous polytetrafluoroethylene/silica composite separator has been prepared and evaluated for its use in all-vanadium mixed-acid redox flow battery. This separator consisting of silica particles enmeshed in a polytetrafluoroethylene fibril matrix has no ion exchange capacity and is featured with unique nanoporous structures, which function as the ion transport channels in redox flow battery operation, with an average pore size of 38nm and a porosity of 48%. This separator has produced excellent electrochemical performance in the all-vanadium mixed-acid system with energy efficiency delivery comparable to Nafion membrane and superior rate capability and temperature tolerance. The separator also demonstrates an exceptional capacity retention capability over extended cycling, offering additional operational latitude towards conveniently mitigating the capacity decay that is inevitable for Nafion. Because of the inexpensive raw materials and simple preparation protocol, the separator is particularly low-cost, estimated to be at least an order of magnitude more inexpensive than Nafion. Plus the proven chemical stability due to the same backbone material as Nafion, this separator possesses a good combination of critical membrane requirements and shows great potential to promote market penetration of the all-vanadium redox flow battery by enabling significant reduction of capital and cycle costs.

Wei, Xiaoliang; Nie, Zimin; Luo, Qingtao; Li, Bin; Chen, Baowei; Simmons, Kevin L.; Sprenkle, Vincent L.; Wang, Wei

2013-09-02T23:59:59.000Z

363

A method of cobalt ion concentration from dilute aqueous solutions  

SciTech Connect (OSTI)

The liquid membrane technique is very useful for metal ions recovery from dilute solutions. Co{sup 2+} ions can be removed and concentrated from wastewaters with an emulsion liquid membrane. The paper describes the permeation of Co{sup 2+} using naphthenic acids as the carrier and kerosene as the membrane material. The inner phase is a HCl 3.162 x 10{sup -4} solution. The extraction yield is more than 96%.

Amanatidou, E. [Technological Education Inst., Kila Kozanis (Greece); Stefanut, M.N.; Grozav, A. [Institute for Chemical and Technological Sciences, Timisoara (Romania)

1996-03-01T23:59:59.000Z

364

Alkaline membrane fuel cells with in-situ cross-linked ionomers Yongjun Leng a  

E-Print Network [OSTI]

optimization is needed for the commercialization of alkaline membrane fuel cell (AMFC) technologiesAlkaline membrane fuel cells with in-situ cross-linked ionomers Yongjun Leng a , Lizhu Wang b membrane fuel cell (AMFC) in-situ cross-linking ionomer net water transport coefficient A B S T R A C

365

Thin film ion conducting coating  

DOE Patents [OSTI]

Durable thin film ion conducting coatings are formed on a transparent glass substrate by the controlled deposition of the mixed oxides of lithium:tantalum or lithium:niobium. The coatings provide durable ion transport sources for thin film solid state storage batteries and electrochromic energy conservation devices.

Goldner, Ronald B. (Lexington, MA); Haas, Terry (Sudbury, MA); Wong, Kwok-Keung (Watertown, MA); Seward, George (Arlington, MA)

1989-01-01T23:59:59.000Z

366

NOVEL COMPOSITE MEMBRANES FOR HYDROGEN SEPARATION IN GASIFICATION PROCESSES IN VISION 21 ENERGY PLANTS  

SciTech Connect (OSTI)

ITN Energy Systems, along with its team members, the Idaho National Engineering and Environmental Laboratory, Nexant Consulting, Argonne National Laboratory and Praxair, propose to develop a novel composite membrane structure for hydrogen separation as a key technology module within the future ''Vision 21'' fossil fuel plants. The ITN team is taking a novel approach to hydrogen separation membrane technology where fundamental engineering material development is fully integrated into fabrication designs; combining functionally graded materials, monolithic module concept and plasma spray manufacturing techniques. The technology is based on the use of Ion Conducting Ceramic Membranes (ICCM) for the selective transport of hydrogen. The membranes are comprised of composites consisting of a proton conducting ceramic and a second metallic phase to promote electrical conductivity. Functional grading of the membrane components allows the fabrication of individual membrane layers of different materials, microstructures and functions directly into a monolithic module. Plasma spray techniques, common in industrial manufacturing, are well suited for fabricating ICCM hydrogen separation modules inexpensively, yielding compact membrane modules that are amenable to large scale, continuous manufacturing with low costs. This program will develop and evaluate composite membranes and catalysts for hydrogen separation. Components of the monolithic modules will be fabricated by plasma spray processing. The engineering and economic characteristics of the proposed ICCM approach, including system integration issues, will also be assessed. This will result in a complete evaluation of the technical and economic feasibility of ICCM hydrogen separation for implementation within the ''Vision 21'' fossil fuel plant. The ICCM hydrogen separation technology is targeted for use within the gasification module of the ''Vision 21'' fossil fuel plant. The high performance and low-cost manufacturing of the proposed technology will benefit the deployment of ''Vision 21'' fossil fuel plant processes by improving the energy efficiency, flexibility and environmental performance of these plants. Of particular importance is that this technology will also produce a stream of pure carbon dioxide. This allows facile sequestration or other use of this greenhouse gas. These features will benefit the U.S. in allowing for the continued use of domestic fossil fuels in a more energy efficient and environmentally acceptable manner.

Michael Schwartz

2003-10-01T23:59:59.000Z

367

NOVEL COMPOSITE MEMBRANES FOR HYDROGEN SEPARATION IN GASIFICATION PROCESSES IN VISION 21 ENERGY PLANTS  

SciTech Connect (OSTI)

ITN Energy Systems, along with its team members, the Idaho National Engineering and Environmental Laboratory, Nexant Consulting, Argonne National Laboratory and Praxair, propose to develop a novel composite membrane structure for hydrogen separation as a key technology module within the future ''Vision 21'' fossil fuel plants. The ITN team is taking a novel approach to hydrogen separation membrane technology where fundamental engineering material development is fully integrated into fabrication designs; combining functionally graded materials, monolithic module concept and plasma spray manufacturing techniques. The technology is based on the use of Ion Conducting Ceramic Membranes (ICCM) for the selective transport of hydrogen. The membranes are comprised of composites consisting of a proton conducting ceramic and a second metallic phase to promote electrical conductivity. Functional grading of the membrane components allows the fabrication of individual membrane layers of different materials, microstructures and functions directly into a monolithic module. Plasma spray techniques, common in industrial manufacturing, are well suited for fabricating ICCM hydrogen separation modules inexpensively, yielding compact membrane modules that are amenable to large scale, continuous manufacturing with low costs. This program will develop and evaluate composite membranes and catalysts for hydrogen separation. Components of the monolithic modules will be fabricated by plasma spray processing. The engineering and economic characteristics of the proposed ICCM approach, including system integration issues, will also be assessed. This will result in a complete evaluation of the technical and economic feasibility of ICCM hydrogen separation for implementation within the ''Vision 21'' fossil fuel plant. The ICCM hydrogen separation technology is targeted for use within the gasification module of the ''Vision 21'' fossil fuel plant. The high performance and low-cost manufacturing of the proposed technology will benefit the deployment of ''Vision 21'' fossil fuel plant processes by improving the energy efficiency, flexibility and environmental performance of these plants. Of particular importance is that this technology will also produce a stream of pure carbon dioxide. This allows facile sequestration or other use of this greenhouse gas. These features will benefit the U.S. in allowing for the continued use of domestic fossil fuels in a more energy efficient and environmentally acceptable manner.

Michael Schwartz

2003-07-01T23:59:59.000Z

368

NOVEL COMPOSITE MEMBRANES FOR HYDROGEN SEPARATION IN GASIFICATION PROCESSES IN VISION 21 ENERGY PLANTS  

SciTech Connect (OSTI)

ITN Energy Systems, along with its team members, the Idaho National Engineering and Environmental Laboratory, Nexant Consulting, Argonne National Laboratory and Praxair, propose to develop a novel composite membrane structure for hydrogen separation as a key technology module within the future ''Vision 21'' fossil fuel plants. The ITN team is taking a novel approach to hydrogen separation membrane technology where fundamental engineering material development is fully integrated into fabrication designs; combining functionally graded materials, monolithic module concept and plasma spray manufacturing techniques. The technology is based on the use of Ion Conducting Ceramic Membranes (ICCM) for the selective transport of hydrogen. The membranes are comprised of composites consisting of a proton conducting ceramic and a second metallic phase to promote electrical conductivity. Functional grading of the membrane components allows the fabrication of individual membrane layers of different materials, microstructures and functions directly into a monolithic module. Plasma spray techniques, common in industrial manufacturing, are well suited for fabricating ICCM hydrogen separation modules inexpensively, yielding compact membrane modules that are amenable to large scale, continuous manufacturing with low costs. This program will develop and evaluate composite membranes and catalysts for hydrogen separation. Components of the monolithic modules will be fabricated by plasma spray processing. The engineering and economic characteristics of the proposed ICCM approach, including system integration issues, will also be assessed. This will result in a complete evaluation of the technical and economic feasibility of ICCM hydrogen separation for implementation within the ''Vision 21'' fossil fuel plant. The ICCM hydrogen separation technology is targeted for use within the gasification module of the ''Vision 21'' fossil fuel plant. The high performance and low-cost manufacturing of the proposed technology will benefit the deployment of ''Vision 21'' fossil fuel plant processes by improving the energy efficiency, flexibility and environmental performance of these plants. Of particular importance is that this technology will also produce a stream of pure carbon dioxide. This allows facile sequestration or other use of this greenhouse gas. These features will benefit the U.S. in allowing for the continued use of domestic fossil fuels in a more energy efficient and environmentally acceptable manner.

Michael Schwartz

2004-01-01T23:59:59.000Z

369

Journal of Membrane Science 279 (2006) 608614 Direct measurement of nanofluxes and structural relaxations of  

E-Print Network [OSTI]

of the membrane are very important in explain- ing solvent swelling [8,9]. Besides water transport, the gas. For insufficiently hydrated Nafion® membranes, the proton transport is slow, and thus, the conversion efficiency. Originally, it was argued that the gas mainly permeates either through the hydrated ionic cluster region [10

370

Membrane Technology Workshop  

Broader source: Energy.gov [DOE]

At the Membrane Technology Workshop (held July 24, 2012, in Rosemont, IL), stakeholders from industry and academia explored the status of membrane research and development (R&D). Participants ...

371

Composite zeolite membranes  

DOE Patents [OSTI]

A new class of composite zeolite membranes and synthesis techniques therefor has been invented. These membranes are essentially defect-free, and exhibit large levels of transmembrane flux and of chemical and isotopic selectivity.

Nenoff, Tina M. (Albuquerque, NM); Thoma, Steven G. (Albuquerque, NM); Ashley, Carol S. (Albuquerque, NM); Reed, Scott T. (Albuquerque, NM)

2002-01-01T23:59:59.000Z

372

Hybrid adsorptive membrane reactor  

DOE Patents [OSTI]

A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

Tsotsis, Theodore T. (Huntington Beach, CA); Sahimi, Muhammad (Altadena, CA); Fayyaz-Najafi, Babak (Richmond, CA); Harale, Aadesh (Los Angeles, CA); Park, Byoung-Gi (Yeosu, KR); Liu, Paul K. T. (Lafayette Hill, PA)

2011-03-01T23:59:59.000Z

373

Supported inorganic membranes  

DOE Patents [OSTI]

Supported inorganic membranes capable of molecular sieving, and methods for their production, are provided. The subject membranes exhibit high flux and high selectivity. The subject membranes are substantially defect free and less than about 100 nm thick. The pores of the subject membranes have an average critical pore radius of less than about 5 .ANG., and have a narrow pore size distribution. The subject membranes are prepared by coating a porous substrate with a polymeric sol, preferably under conditions of low relative pressure of the liquid constituents of the sol. The coated substrate is dried and calcined to produce the subject supported membrane. Also provided are methods of derivatizing the surface of supported inorganic membranes with metal alkoxides. The subject membranes find use in a variety of applications, such as the separation of constituents of gaseous streams, as catalysts and catalyst supports, and the like.

Sehgal, Rakesh (Albuquerque, NM); Brinker, Charles Jeffrey (Albuquerque, NM)

1998-01-01T23:59:59.000Z

374

Ion pump activity generates fluctuating electrostatic forces in biomembranes  

E-Print Network [OSTI]

We study the non-equilibrium dynamics of lipid membranes with proteins that actively pump ions across the membrane. We find that the activity leads to a fluctuating force distribution due to electrostatic interactions arising from variation in dielectric constant across the membrane. By applying a multipole expansion we find effects on both the tension and bending rigidity dominated parts of the membranes fluctuation spectrum. We discuss how our model compares with previous studies of force-multipole models.

B. Loubet; M. A. Lomholt

2011-09-19T23:59:59.000Z

375

Simulation and Analysis of Human Phantoms Exposed to Heavy Charged Particle Irradiations Using the Particle and Heavy Ion Transport System (PHITS)  

E-Print Network [OSTI]

. ...................................................................... 10 5 Dose distributions as the result of the MASTOSHKA experiment ........... 11 6 The exterior shapes of the MIRD-5 and ORNL-UF phantom models ....... 19 7 The interior shapes of the MIRD-5 and ORNL-UF phantom models ........ 20 8... phantoms such as Medical Internal Radiation Dose (MIRD) 3 approach [6], and others derived from MIRD, were based on A General Monte Carlo N- Particle Transport Code (MCNP) and are, therefore, limited only to neutron, photon, and electron exposures [7...

Lee, Dongyoul

2012-02-14T23:59:59.000Z

376

Membrane Technology Workshop  

Broader source: Energy.gov [DOE]

Presentation by Charles Page (Air Products & Chemicals, Inc.) for the Membrane Technology Workshop held July 24, 2012

377

Membrane Separations Research  

E-Print Network [OSTI]

MEMBRANE SEPARATIONS RESEARCH James R. Fair Chemical Engineering Department The University of Texas at Austin Austin, TX 78712 ABSTRACT The use of membranes for separating gaseous and liquid mixtures has grown dramatically in the past 15... years. Applications have been dominated by light gas separations and water purification. During this pioneering period, equipment containing the membrane suIfaces has been developed to a point where failures are minimal and the membranes themselves...

Fair, J. R.

378

Cadmium sulfide membranes  

DOE Patents [OSTI]

A method is described for the creation of novel q-effect cadmium sulfide membranes. The membranes are made by first creating a dilute cadmium sulfide colloid in aqueous suspension and then removing the water and excess salts therefrom. The cadmium sulfide membrane thus produced is luminescent at room temperature and may have application in laser fabrication.

Spanhel, Lubomir (Madison, WI); Anderson, Marc A. (Madison, WI)

1991-10-22T23:59:59.000Z

379

Cadmium sulfide membranes  

DOE Patents [OSTI]

A method is described for the creation of novel q-effect cadmium sulfide membranes. The membranes are made by first creating a dilute cadmium sulfide colloid in aqueous suspension and then removing the water and excess salts therefrom. The cadmium sulfide membrane thus produced is luminescent at room temperature and may have application in laser fabrication.

Spanhel, Lubomir (Madison, WI); Anderson, Marc A. (Madison, WI)

1992-07-07T23:59:59.000Z

380

Meniscus Membranes For Separation  

DOE Patents [OSTI]

Gas separation membranes, especially meniscus-shaped membranes for gas separations are disclosed together with the use of such meniscus-shaped membranes for applications such as thermal gas valves, pre-concentration of a gas stream, and selective pre-screening of a gas stream. In addition, a rapid screening system for simultaneously screening polymer materials for effectiveness in gas separation is provided.

Dye, Robert C. (Irvine, CA); Jorgensen, Betty (Jemez Springs, NM); Pesiri, David R. (Aliso Viejo, CA)

2005-09-20T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Meniscus membranes for separations  

DOE Patents [OSTI]

Gas separation membranes, especially meniscus-shaped membranes for gas separations are disclosed together with the use of such meniscus-shaped membranes for applications such as thermal gas valves, pre-concentration of a gas stream, and selective pre-screening of a gas stream. In addition, a rapid screening system for simultaneously screening polymer materials for effectiveness in gas separation is provided.

Dye, Robert C. (Irvine, CA); Jorgensen, Betty (Jemez Springs, NM); Pesiri, David R. (Aliso Viejo, CA)

2004-01-27T23:59:59.000Z

382

Polyphosphazene semipermeable membranes  

DOE Patents [OSTI]

A semipermeable, inorganic membrane is disclosed; the membrane is prepared from a phosphazene polymer and, by the selective substitution of the constituent groups bound to the phosphorous in the polymer structure, the selective passage of fluid from a feedstream can be controlled. Resistance to high temperatures and harsh chemical environments is observed in the use of the phosphazene polymers as semipermeable membranes.

Allen, Charles A. (Idaho Falls, ID); McCaffrey, Robert R. (Idaho Falls, ID); Cummings, Daniel G. (Idaho Falls, ID); Grey, Alan E. (Idaho Falls, ID); Jessup, Janine S. (Darlington, ID); McAtee, Richard E. (Idaho Falls, ID)

1988-01-01T23:59:59.000Z

383

Transport properties of discontinuous Co{sub 80}Fe{sub 20}/Al{sub 2}O{sub 3} multilayers, prepared by ion beam sputtering  

SciTech Connect (OSTI)

Ion beam sputtered Co{sub 80}Fe{sub 20}(t)/Al{sub 2}O{sub 3}(30 {angstrom}) multilayers were obtained. The Co{sub 80}Fe{sub 20} layers become discontinuous for nominal thicknesses T {le} 18{angstrom}. Tunnel magnetoresistance was measured in CIP and CPP geometries, reaching up to 6.5% at room temperature and 11% at 15 K, for as-deposited films in CIP geometry. The temperature dependence of MR was found quite different for the two geometries: fairly strong in the CIP case and almost absent in the CPP geometry. A model is proposed to explain these large differences in behavior.

Kakazei, G.N.; Freitas, P.P.; Cardoso, S.; Lopes, A.M.L.; Pereira de Azevedo, M.M.; Pogorelov, Y.G.; Sousa, J.B.

1999-09-01T23:59:59.000Z

384

EFFECT OF COMPRESSION ON CONDUCTIVITY AND MORPHOLOGY OF PFSA MEMBRANES  

SciTech Connect (OSTI)

Polymer-Electrolyte-Fuel-Cells (PEFCs) are promising candidates for powering vehicles and portable devices using renewable-energy sources. The core of a PEFC is the solid electrolyte membrane that conducts protons from anode to cathode, where water is generated. The conductivity of the membrane, however, depends on the water content of the membrane, which is strongly related to the cell operating conditions. The membrane and other cell components are typically compressed to minimize various contact resistances. Moreover, the swelling of a somewhat constrained membrane in the cell due to the humidity changes generates additional compressive stresses in the membrane. These external stresses are balanced by the internal swelling pressure of the membrane and change the swelling equilibrium. It was shown using a fuel-cell setup that compression could reduce the water content of the membrane or alter the cell resistance. Nevertheless, the effect of compression on the membranes transport properties is yet to be understood, as well as its implications in the structure-functions relationships of the membrane. We previously studied, both experimentally and theoretically, how compression affects the water content of the membrane.6 However, more information is required the gain a fundamental understanding of the compression effects. In this talk, we present the results of our investigation on the in-situ conductivity of the membrane as a function of humidity and cell compression pressure. Moreover, to better understand the morphology of compressed membrane, small-angle X-ray-scattering (SAXS) experiments were performed. The conductivity data is then analyzed by investigating the size of the water domains of the compressed membrane determined from the SAXS measurements.

Kusoglu, Ahmet; Weber, Adam; Jiang, Ruichin; Gittleman, Craig

2011-07-20T23:59:59.000Z

385

Oxygen ion conducting materials  

DOE Patents [OSTI]

An oxygen ion conducting ceramic oxide that has applications in industry including fuel cells, oxygen pumps, oxygen sensors, and separation membranes. The material is based on the idea that substituting a dopant into the host perovskite lattice of (La,Sr)MnO.sub.3 that prefers a coordination number lower than 6 will induce oxygen ion vacancies to form in the lattice. Because the oxygen ion conductivity of (La,Sr)MnO.sub.3 is low over a very large temperature range, the material exhibits a high overpotential when used. The inclusion of oxygen vacancies into the lattice by doping the material has been found to maintain the desirable properties of (La,Sr)MnO.sub.3, while significantly decreasing the experimentally observed overpotential.

Vaughey, John; Krumpelt, Michael; Wang, Xiaoping; Carter, J. David

2005-07-12T23:59:59.000Z

386

Oxygen ion conducting materials  

DOE Patents [OSTI]

An oxygen ion conducting ceramic oxide that has applications in industry including fuel cells, oxygen pumps, oxygen sensors, and separation membranes. The material is based on the idea that substituting a dopant into the host perovskite lattice of (La,Sr)MnO.sub.3 that prefers a coordination number lower than 6 will induce oxygen ion vacancies to form in the lattice. Because the oxygen ion conductivity of (La,Sr)MnO.sub.3 is low over a very large temperature range, the material exhibits a high overpotential when used. The inclusion of oxygen vacancies into the lattice by doping the material has been found to maintain the desirable properties of (La,Sr)MnO.sub.3, while significantly decreasing the experimentally observed overpotential.

Carter, J. David; Wang, Xiaoping; Vaughey, John; Krumpelt, Michael

2004-11-23T23:59:59.000Z

387

Oxygen ion conducting materials  

DOE Patents [OSTI]

An oxygen ion conducting ceramic oxide that has applications in industry including fuel cells, oxygen pumps, oxygen sensors, and separation membranes. The material is based on the idea that substituting a dopant into the host perovskite lattice of (La,Sr)MnO.sub.3 that prefers a coordination number lower than 6 will induce oxygen ion vacancies to form in the lattice. Because the oxygen ion conductivity of (La,Sr)MnO.sub.3 is low over a very large temperature range, the material exhibits a high overpotential when used. The inclusion of oxygen vacancies into the lattice by doping the material has been found to maintain the desirable properties of (La,Sr)MnO.sub.3, while significantly decreasing the experimentally observed overpotential.

Vaughey, John (Elmhurst, IL); Krumpelt, Michael (Naperville, IL); Wang, Xiaoping (Downers Grove, IL); Carter, J. David (Bolingbrook, IL)

2003-01-01T23:59:59.000Z

388

Molecular Mechanism of Biological Proton Transport  

SciTech Connect (OSTI)

Proton transport across lipid membranes is a fundamental aspect of biological energy transduction (metabolism). This function is mediated by a Grotthuss mechanism involving proton hopping along hydrogen-bonded networks embedded in membrane-spanning proteins. Using molecular simulations, the authors have explored the structural, dynamic, and thermodynamic properties giving rise to long-range proton translocation in hydrogen-bonded networks involving water molecules, or water wires, which are emerging as ubiquitous H{sup +}-transport devices in biological systems.

Pomes, R.

1998-09-01T23:59:59.000Z

389

Identification and characterization of a bacterial hydrosulphide ion channel  

SciTech Connect (OSTI)

The hydrosulphide ion (HS{sup -}) and its undissociated form, hydrogen sulphide (H{sub 2}S), which are believed to have been critical to the origin of life on Earth, remain important in physiology and cellular signalling. As a major metabolite in anaerobic bacterial growth, hydrogen sulphide is a product of both assimilatory and dissimilatory sulphate reduction. These pathways can reduce various oxidized sulphur compounds including sulphate, sulphite and thiosulphate. The dissimilatory sulphate reduction pathway uses this molecule as the terminal electron acceptor for anaerobic respiration, in which process it produces excess amounts of H{sub 2}S. The reduction of sulphite is a key intermediate step in all sulphate reduction pathways. In Clostridium and Salmonella, an inducible sulphite reductase is directly linked to the regeneration of NAD{sup +}, which has been suggested to have a role in energy production and growth, as well as in the detoxification of sulphite. Above a certain concentration threshold, both H{sub 2}S and HS{sup -} inhibit cell growth by binding the metal centres of enzymes and cytochrome oxidase, necessitating a release mechanism for the export of this toxic metabolite from the cell. Here we report the identification of a hydrosulphide ion channel in the pathogen Clostridium difficile through a combination of genetic, biochemical and functional approaches. The HS{sup -} channel is a member of the formate/nitrite transport family, in which about 50 hydrosulphide ion channels form a third subfamily alongside those for formate (FocA) and for nitrite (NirC). The hydrosulphide ion channel is permeable to formate and nitrite as well as to HS{sup -} ions. Such polyspecificity can be explained by the conserved ion selectivity filter observed in the channel's crystal structure. The channel has a low open probability and is tightly regulated, to avoid decoupling of the membrane proton gradient.

Czyzewski, Bryan K.; Wang, Da-Neng (NYUSM)

2012-10-26T23:59:59.000Z

390

Enhanced membrane gas separations  

SciTech Connect (OSTI)

An improved membrane gas separation process is described comprising: (a) passing a feed gas stream to the non-permeate side of a membrane system adapted for the passage of purge gas on the permeate side thereof, and for the passage of the feed gas stream in a counter current flow pattern relative to the flow of purge gas on the permeate side thereof, said membrane system being capable of selectively permeating a fast permeating component from said feed gas, at a feed gas pressure at or above atmospheric pressure; (b) passing purge gas to the permeate side of the membrane system in counter current flow to the flow of said feed gas stream in order to facilitate carrying away of said fast permeating component from the surface of the membrane and maintaining the driving force for removal of the fast permeating component through the membrane from the feed gas stream, said permeate side of the membrane being maintained at a subatmospheric pressure within the range of from about 0.1 to about 5 psia by vacuum pump means; (c) recovering a product gas stream from the non-permeate side of the membrane; and (d) discharging purge gas and the fast permeating component that has permeated the membrane from the permeate side of the membrane, whereby the vacuum conditions maintained on the permeate side of the membrane by said vacuum pump means enhance the efficiency of the gas separation operation, thereby reducing the overall energy requirements thereof.

Prasad, R.

1993-07-13T23:59:59.000Z

391

E-Print Network 3.0 - acid-sensing ion channel Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

acid-sensing... or distortion by causing membrane depolarization and action potential firing. Mechanotransducer channel An ion... ... Source: Alford, Simon - Department of...

392

Novel Composite Membranes for Hydrogen Separation in Gasification Processes in Vision 21 Energy Plants  

SciTech Connect (OSTI)

ITN Energy Systems, Inc. (ITN) and its partners, the Idaho National Engineering and Environmental Laboratory, Argonne National Laboratory, Nexant Consulting, LLC and Praxair, Inc. are developing composite membranes for hydrogen separation as a key technology module within the future ''Vision 21'' fossil fuel plants. The ITN team is pursuing a novel approach to hydrogen separation membrane technology where fundamental engineering material development is fully integrated into module fabrication designs; combining functionally-graded materials, monolithic module concept and thermal spray manufacturing techniques. The technology is based on the use of Ion Conducting Ceramic Membranes (ICCM) for the selective transport of hydrogen. The membranes are comprised of composites consisting of a proton conducting ceramic and a second metallic phase to promote electrical conductivity. Functional grading of the membrane components allows for the fabrication of individual membrane layers of different materials, microstructures and functions directly into a monolithic module. Plasma spray techniques, common in industrial manufacturing, are well suited for fabricating ICCM hydrogen separation modules inexpensively, yielding compact membrane modules that are amenable to large scale, continuous manufacturing techniques with low costs. The engineering and economic characteristics of the proposed ICCM approach, including system integration issues, are being assessed. This will result in an evaluation of the technical and economic feasibility of the proposed ICCM hydrogen separation approach for implementation within the ''Vision 21'' fossil fuel plant. The ICCM hydrogen separation technology is targeted for use within the gasification module of the ''Vision 21'' fossil fuel plant. The high performance and low-cost manufacturing of the proposed technology will benefit the deployment of ''Vision 21'' fossil fuel plant processes by improving the energy efficiency, flexibility and environmental performance of such plants. Of particular importance is that the proposed technology also results in a stream of pure carbon dioxide. This allows for the facile sequestration or other use of this greenhouse gas. These features will benefit the U.S. in allowing for the continued use of domestic fossil fuels in a more energy efficient and environmentally acceptable manner.

Schwartz, Michael

2001-11-06T23:59:59.000Z

393

E-Print Network 3.0 - aqueous lithium-ion battery Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Summary: -board identification and diagnostics for Lithium Ion batteries. The electrochemical, electrical, and transport... and cost Target, Current technology status...

394

Substituted polyacetylene separation membrane  

DOE Patents [OSTI]

A separation membrane is described which is useful for gas separation, particularly separation of C{sub 2+} hydrocarbons from natural gas. The invention encompasses the membrane itself, methods of making it and processes for using it. The membrane comprises a polymer having repeating units of a hydrocarbon-based, disubstituted polyacetylene, having the general formula shown in the accompanying diagram, wherein R{sub 1} is chosen from the group consisting of C{sub 1}-C{sub 4} alkyl and phenyl, and wherein R{sub 2} is chosen from the group consisting of hydrogen and phenyl. In the most preferred embodiment, the membrane comprises poly(4-methyl-2-pentyne) [PMP]. The membrane exhibits good chemical resistance and has super-glassy properties with regard to separating certain large, condensable permeant species from smaller, less-condensable permeant species. The membranes may also be useful in other fluid separations. 4 figs.

Pinnau, I.; Morisato, Atsushi

1998-01-13T23:59:59.000Z

395

Substituted polyacetylene separation membrane  

DOE Patents [OSTI]

A separation membrane useful for gas separation, particularly separation of C.sub.2+ hydrocarbons from natural gas. The invention encompasses the membrane itself, methods of making it and processes for using it. The membrane comprises a polymer having repeating units of a hydrocarbon-based, disubstituted polyacetylene, having the general formula: ##STR1## wherein R.sub.1 is chosen from the group consisting of C.sub.1 -C.sub.4 alkyl and phenyl, and wherein R.sub.2 is chosen from the group consisting of hydrogen and phenyl. In the most preferred embodiment, the membrane comprises poly(4-methyl-2-pentyne) PMP!. The membrane exhibits good chemical resistance and has super-glassy properties with regard to separating certain large, condensable permeant species from smaller, less-condensable permeant species. The membranes may also be useful in other fluid separations.

Pinnau, Ingo (Palo Alto, CA); Morisato, Atsushi (Tokyo, JP)

1998-01-13T23:59:59.000Z

396

Siloxane-grafted membranes  

DOE Patents [OSTI]

Composite cellulosic semipermeable membranes are disclosed which are the covalently bonded reaction product of an asymmetric cellulosic semipermeable membrane and a polysiloxane containing reactive functional group. The two reactants chemically bond by ether, ester, amide or acrylate linkages to form a siloxane-grafted cellulosic membrane having superior selectivity and flux stability. Selectivity may be enhanced by wetting the surface with a swelling agent such as water.

Friesen, D.T.; Obligin, A.S.

1989-10-31T23:59:59.000Z

397

Net-baryon-, net-proton-, and net-charge kurtosis in heavy-ion collisions within a relativistic transport approach  

E-Print Network [OSTI]

We explore the potential of net-baryon, net-proton and net-charge kurtosis measurements to investigate the properties of hot and dense matter created in relativistic heavy-ion collisions. Contrary to calculations in a grand canonical ensemble we explicitly take into account exact electric and baryon charge conservation on an event-by-event basis. This drastically limits the width of baryon fluctuations. A simple model to account for this is to assume a grand-canonical distribution with a sharp cut-off at the tails. We present baseline predictions of the energy dependence of the net-baryon, net-proton and net-charge kurtosis for central ($b\\leq 2.75$ fm) Pb+Pb/Au+Au collisions from $E_{lab}=2A$ GeV to $\\sqrt{s_{NN}}=200$ GeV from the UrQMD model. While the net-charge kurtosis is compatible with values around zero, the net-baryon number decreases to large negative values with decreasing beam energy. The net-proton kurtosis becomes only slightly negative for low $\\sqrt{s_{NN}}$.

Marlene Nahrgang; Tim Schuster; Michael Mitrovski; Reinhard Stock; Marcus Bleicher

2012-09-03T23:59:59.000Z

398

EXTRACTION COMPRESSION AND ACCELERATION OF HIGH LINE CHARGE DENSITY ION BEAMS  

E-Print Network [OSTI]

on compression of heavy ion beams for creating high energyet al, Highly Compressed Ion Beams for High Energy DensityPulsed Solenoid for Intense Ion Beam Transport, these Proc:

Henestroza, E.

2008-01-01T23:59:59.000Z

399

EVALUATION OF PROTON-CONDUCTING MEMBRANES FOR USE IN A SULFUR-DIOXIDE DEPOLARIZED ELECTROLYZER  

SciTech Connect (OSTI)

The chemical stability, sulfur dioxide transport, ionic conductivity, and electrolyzer performance have been measured for several commercially available and experimental proton exchange membranes (PEMs) for use in a sulfur dioxide depolarized electrolyzer (SDE). The SDE's function is to produce hydrogen by using the Hybrid Sulfur (HyS) Process, a sulfur based electrochemical/thermochemical hybrid cycle. Membrane stability was evaluated using a screening process where each candidate PEM was heated at 80 C in 60 wt. % H{sub 2}SO{sub 4} for 24 hours. Following acid exposure, chemical stability for each membrane was evaluated by FTIR using the ATR sampling technique. Membrane SO{sub 2} transport was evaluated using a two-chamber permeation cell. SO{sub 2} was introduced into one chamber whereupon SO{sub 2} transported across the membrane into the other chamber and oxidized to H{sub 2}SO{sub 4} at an anode positioned immediately adjacent to the membrane. The resulting current was used to determine the SO{sub 2} flux and SO{sub 2} transport. Additionally, membrane electrode assemblies (MEAs) were prepared from candidate membranes to evaluate ionic conductivity and selectivity (ionic conductivity vs. SO{sub 2} transport) which can serve as a tool for selecting membranes. MEAs were also performance tested in a HyS electrolyzer measuring current density versus a constant cell voltage (1V, 80 C in SO{sub 2} saturated 30 wt% H2SO{sub 4}). Finally, candidate membranes were evaluated considering all measured parameters including SO{sub 2} flux, SO{sub 2} transport, ionic conductivity, HyS electrolyzer performance, and membrane stability. Candidate membranes included both PFSA and non-PFSA polymers and polymer blends of which the non-PFSA polymers, BPVE-6F and PBI, showed the best selectivity.

Hobbs, D.; Elvington, M.; Colon-Mercado, H.

2009-11-11T23:59:59.000Z

400

Lead-selective membrane potentiometric sensor based on a recently synthesized bis(anthraquinone) sulfide derivative  

SciTech Connect (OSTI)

The need for monitoring of toxic heavy metal ions in environmental samples has prompted the development of ion-selective electrodes for these ions. A new PVC membrane electrode for lead ions, based on bis[(1-hydroxy-9,10-anthraquinone)-2-methyl]sulfide as membrane carrier, was prepared. The sensor exhibits a Nernstian response for Pb{sup 2+} over a wide concentration range (5.6 {times} 10{sup {minus}3}--4.0 {times} 10{sup {minus}6} M). It has a response time of about 30 s and can be used for at least 3 months without any divergence in potentials. The proposed membrane sensor revealed good selectivities for Pb{sup 2+} over a wide variety of other metal ions. It was used as an indicator electrode in potentiometric titration of lead ion.

Pouretedal, H.R.; Forghaniha, A.; Sharghi, H. [Shiraz Univ. (Iran, Islamic Republic of). Dept. of Chemistry; Shamsipur, M. [Razi Univ., Kermanshah (Iran, Islamic Republic of). Dept. of Chemistry

1998-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Integrated Ceramic Membrane System for Hydrogen Production  

SciTech Connect (OSTI)

Phase I was a technoeconomic feasibility study that defined the process scheme for the integrated ceramic membrane system for hydrogen production and determined the plan for Phase II. The hydrogen production system is comprised of an oxygen transport membrane (OTM) and a hydrogen transport membrane (HTM). Two process options were evaluated: 1) Integrated OTM-HTM reactor in this configuration, the HTM was a ceramic proton conductor operating at temperatures up to 900C, and 2) Sequential OTM and HTM reactors in this configuration, the HTM was assumed to be a Pd alloy operating at less than 600C. The analysis suggested that there are no technical issues related to either system that cannot be managed. The process with the sequential reactors was found to be more efficient, less expensive, and more likely to be commercialized in a shorter time than the single reactor. Therefore, Phase II focused on the sequential reactor system, specifically, the second stage, or the HTM portion. Work on the OTM portion was conducted in a separate program. Phase IIA began in February 2003. Candidate substrate materials and alloys were identified and porous ceramic tubes were produced and coated with Pd. Much effort was made to develop porous substrates with reasonable pore sizes suitable for Pd alloy coating. The second generation of tubes showed some improvement in pore size control, but this was not enough to get a viable membrane. Further improvements were made to the porous ceramic tube manufacturing process. When a support tube was successfully coated, the membrane was tested to determine the hydrogen flux. The results from all these tests were used to update the technoeconomic analysis from Phase I to confirm that the sequential membrane reactor system can potentially be a low-cost hydrogen supply option when using an existing membrane on a larger scale. Phase IIB began in October 2004 and focused on demonstrating an integrated HTM/water gas shift (WGS) reactor to increase CO conversion and produce more hydrogen than a standard water gas shift reactor would. Substantial improvements in substrate and membrane performance were achieved in another DOE project (DE-FC26-07NT43054). These improved membranes were used for testing in a water gas shift environment in this program. The amount of net H2 generated (defined as the difference of hydrogen produced and fed) was greater than would be produced at equilibrium using conventional water gas shift reactors up to 75 psig because of the shift in equilibrium caused by continuous hydrogen removal. However, methanation happened at higher pressures, 100 and 125 psig, and resulted in less net H2 generated than would be expected by equilibrium conversion alone. An effort to avoid methanation by testing in more oxidizing conditions (by increasing CO2/CO ratio in a feed gas) was successful and net H2 generated was higher (40-60%) than a conventional reactor at equilibrium at all pressures tested (up to 125 psig). A model was developed to predict reactor performance in both cases with and without methanation. The required membrane area depends on conditions, but the required membrane area is about 10 ft2 to produce about 2000 scfh of hydrogen. The maximum amount of hydrogen that can be produced in a membrane reactor decreased significantly due to methanation from about 2600 scfh to about 2400 scfh. Therefore, it is critical to eliminate methanation to fully benefit from the use of a membrane in the reaction. Other modeling work showed that operating a membrane reactor at higher temperature provides an opportunity to make the reactor smaller and potentially provides a significant capital cost savings compared to a shift reactor/PSA combination.

Schwartz, Joseph; Lim, Hankwon; Drnevich, Raymond

2010-08-05T23:59:59.000Z

402

SLAC1-related signal transduction pathway involved in ABA- induced stomatal closure and K? selective transport by the OsHKT2;4 transporter from rice (Oryza sativa) with atypical Na? transport properties and competition in permeation of K? over Mg? and Ca? ions  

E-Print Network [OSTI]

of K + over Mg 2+ and Ca 2+ ions Figure 2.1. OsHKT2;4protein kinases with distinct Ca 2+ affinities. Proc. Natl.Abscisic Acid, CO 2 , and Ca 2 + Signaling. Annu. Rev. Plant

Brodsky, Dennis E.

2011-01-01T23:59:59.000Z

403

Novel Redox Shuttles for Overcharge Protection of Lithium-Ion...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Redox Shuttles for Overcharge Protection of Lithium-Ion Batteries Technology available for licensing: Electrolytes containing novel redox shuttles (electron transporters) for...

404

Membrane module assembly  

DOE Patents [OSTI]

A membrane module assembly is described which is adapted to provide a flow path for the incoming feed stream that forces it into prolonged heat-exchanging contact with a heating or cooling mechanism. Membrane separation processes employing the module assembly are also disclosed. The assembly is particularly useful for gas separation or pervaporation. 2 figures.

Kaschemekat, J.

1994-03-15T23:59:59.000Z

405

Microporous alumina ceramic membranes  

DOE Patents [OSTI]

Several methods are disclosed for the preparation microporous alumina ceramic membranes. For the first time, porous alumina membranes are made which have mean pore sizes less than 100 Angstroms and substantially no pores larger than that size. The methods are based on improved sol-gel techniques.

Anderson, M.A.; Guangyao Sheng.

1993-05-04T23:59:59.000Z

406

Novel, Ceramic Membrane System For Hydrogen Separation  

SciTech Connect (OSTI)

Separation of hydrogen from coal gas represents one of the most promising ways to produce alternative sources of fuel. Ceramatec, teamed with CoorsTek and Sandia National Laboratories has developed materials technology for a pressure driven, high temperature proton-electron mixed conducting membrane system to remove hydrogen from the syngas. This system separates high purity hydrogen and isolates high pressure CO{sub 2} as the retentate, which is amenable to low cost capture and transport to storage sites. The team demonstrated a highly efficient, pressure-driven hydrogen separation membrane to generate high purity hydrogen from syngas using a novel ceramic-ceramic composite membrane. Recognizing the benefits and limitations of present membrane systems, the all-ceramic system has been developed to address the key technical challenges related to materials performance under actual operating conditions, while retaining the advantages of thermal and process compatibility offered by the ceramic membranes. The feasibility of the concept has already been demonstrated at Ceramatec. This project developed advanced materials composition for potential integration with water gas shift rectors to maximize the hydrogenproduction.

Elangovan, S.

2012-12-31T23:59:59.000Z

407

Nanocomposite Membranes for Complex Separations  

E-Print Network [OSTI]

membranes for reverse-selective removal of alkanes from light gases, 2) defect-free inorganic nanocomposite membranes that have uniform pores, and 3) nanocomposite membranes for minimizing protein fouling in microfiltration applications. Reverse-selective...

Yeu, Seung Uk

2010-10-12T23:59:59.000Z

408

E-Print Network 3.0 - anion transporter sat1 Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

(ClC) family... in the complex network of membrane transport and solute fluxes. We used a reverse genetics approach with T Source: Groningen, Rijksuniversiteit - Centre for...

409

E-Print Network 3.0 - anion transporters oat1 Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

(ClC) family... in the complex network of membrane transport and solute fluxes. We used a reverse genetics approach with T Source: Groningen, Rijksuniversiteit - Centre for...

410

Composition variation and underdamped mechanics near membrane proteins and coats  

E-Print Network [OSTI]

We study the effect of membrane proteins on the shape, composition and thermodynamic stability of the surrounding membrane. When the coupling between membrane composition and curvature is strong enough the nearby composition and shape both undergo a transition from over-damped to under-damped spatial variation, well before the membrane becomes unstable in the bulk. This transition is associated with a change in the sign of the thermodynamic energy and hence has the unusual features that it can favour the early stages of coat assembly necessary for vesiculation (budding), while suppressing the activity of mechanosensitive membrane channels and transporters. Our results also suggest an approach to obtain physical parameters that are otherwise difficult to measure.

S. Alex Rautu; George Rowlands; Matthew S. Turner

2015-02-14T23:59:59.000Z

411

Experimental constraints on transport  

SciTech Connect (OSTI)

Characterization of the cross-field energy transport in magnetic confinement experiments in a manner applicable to the accurate assessment of future machine performance continues to be a challenging goal. Experimental results from the DIII-D tokamak in the areas of dimensionless scaling and non-diffusive transport represent progress toward this goal. Dimensionless scaling shows how beneficial the increase in machine size and magnetic field is for future devices. The experiments on DIII-D are the first to determine separately the electron and ion scaling with normalized gyroradius {rho}{sub *}; the electrons scale as expected from gyro-Bohm class theories, while the ions scale consistent with the Goldston empirical scaling. This result predicts an increase in transport relative to Bohm diffusion as {rho}{sub *} decreases in future devices. The existence of distinct {rho}{sub *} scalings for ions and electrons cautions against a physical interpretation of one-fluid or global analysis. The second class of experiments reported here are the first to demonstrate the existence of non-diffusive energy transport. Electron cyclotron heating was applied at the half radius; the electron temperature profile remains substantially peaked. Power balance analysis indicates that heat must flow in the direction of increasing temperature, which is inconsistent with purely diffusive transport. The dynamics of electron temperature perturbations indicate the presence in the heat flux of a term dependent on temperature rather than its gradient. These two observations strongly constrain the types of models which can be applied to cross-field heat transport.

Luce, T.C.; Petty, K.H.; Burrell, K.H.; Forest, C.B.; Gohil, P.; Groebner, R.J.; De Haas, J.C.M.; James, R.A.; Makowski, M.A.

1994-12-01T23:59:59.000Z

412

Transportation Services  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Transportation Services Transporting nuclear materials within the United States and throughout the world is a complicated and sometimes highly controversial effort requiring...

413

Local Transportation  

E-Print Network [OSTI]

Local Transportation. Transportation from the Airport to Hotel. There are two types of taxi companies that operate at the airport: special and regular taxis (

414

Greening Transportation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Transportation Goal 2: Greening Transportation LANL supports and encourages employees to reduce their personal greenhouse gas emissions by offering various commuting and work...

415

Original article Flat ceramic membranes  

E-Print Network [OSTI]

membranes. The orig- inal intellectual concept is protected by two international patents. Strategically of investment and functioning costs while keeping the interest of ceramics. ceramic membrane / plate / tubular

Paris-Sud XI, Université de

416

Method and apparatus for removing ions from soil  

DOE Patents [OSTI]

A method and apparatus are presented for selectively removing species of ions from an area of soil. Permeable membranes 14 and 18 impregnated with an ion exchange resin that is specific to one or more species of chemical ions are inserted into ground 12 in close proximity to, and on opposing sides of, a soil area of interest 22. An electric potential is applied across electrodes 26 and 28 to cause the migration of ions out of soil area 22 toward the membranes 14 and 18. Preferably, the resin exchanges ions of sodium or hydrogen for ions of mercury that it captures from soil area 22. Once membranes 14 and 18 become substantially saturated with mercury ions, the potential applied across electrodes 26 and 28 is discontinued and membranes 14 and 18 are preferably removed from soil 12 for storage or recovery of the ions. The membranes are also preferably impregnated with a buffer to inhibit the effect of the hydrolysis of water by current from the electrodes.

Bibler, J.P.

1993-03-02T23:59:59.000Z

417

Method and apparatus for removing ions from soil  

DOE Patents [OSTI]

A method and apparatus for selectively removing species of ions from an area of soil. Permeable membranes 14 and 18 impregnated with an ion exchange resin that is specific to one or more species of chemical ions are inserted into ground 12 in close proximity to, and on opposing sides of, a soil area of interest 22. An electric potential is applied across electrodes 26 and 28 to cause the migration of ions out of soil area 22 toward the membranes 14 and 18. Preferably, the resin exchanges ions of sodium or hydrogen for ions of mercury that it captures from soil area 22. Once membranes 14 and 18 become substantially saturated with mercury ions, the potential applied across electrodes 26 and 28 is discontinued and membranes 14 and 18 are preferably removed from soil 12 for storage or recovery of the ions. The membranes are also preferably impregnated with a buffer to inhibit the effect of the hydrolysis of water by current from the electrodes.

Bibler, Jane P. (813 E. Rollingwood Rd., Aiken, SC 29801)

1993-01-01T23:59:59.000Z

418

Final Report for DE-FG02-93ER14376,Ionic Transport in Electrochemical Media  

SciTech Connect (OSTI)

This project was a molecular dynamics study of the relevant issues associated with the structure and transport of lithium in polymer electrolytes such as polyethylene oxide(PEO). In close collaboration with quantum chemist Larry Curtiss and neutron scatterers David Lee Price and Marie-Louise Saboungi at Argonne, we used molecular dynamics to study the local structure and dynamics and ion transport in the polymer. The studies elucidated the mechanism of Li transport in PEO, revealing that the rate limiting step is extremely sensitive to the magnitude of the torsion forces in the backbone of the polymer. Because the torsion forces are difficult to manipulate chemically, this makes it easier to understand why improving the conductivity of PEO based electrolytes has proven to be very difficult. We studied the transport properties of cations in ionic liquids as possible additives to polymer membranes for batteries and fuel cells and found preliminary indications that the transport is enhanced near phase separation in acid-ionic liquid mixtures.

J. W. Halley

2009-05-20T23:59:59.000Z

419

Catalytic nanoporous membranes  

DOE Patents [OSTI]

A nanoporous catalytic membrane which displays several unique features Including pores which can go through the entire thickness of the membrane. The membrane has a higher catalytic and product selectivity than conventional catalysts. Anodic aluminum oxide (AAO) membranes serve as the catalyst substrate. This substrate is then subjected to Atomic Layer Deposition (ALD), which allows the controlled narrowing of the pores from 40 nm to 10 nm in the substrate by deposition of a preparatory material. Subsequent deposition of a catalytic layer on the inner surfaces of the pores reduces pore sizes to less than 10 nm and allows for a higher degree of reaction selectivity. The small pore sizes allow control over which molecules enter the pores, and the flow-through feature can allow for partial oxidation of reactant species as opposed to complete oxidation. A nanoporous separation membrane, produced by ALD is also provided for use in gaseous and liquid separations. The membrane has a high flow rate of material with 100% selectivity. Also provided is a method for producing a catalytic membrane having flow-through pores and discreet catalytic clusters adhering to the inside surfaces of the pores.

Pellin, Michael J; Hryn, John N; Elam, Jeffrey W

2013-08-27T23:59:59.000Z

420

Cyclic membrane separation process  

DOE Patents [OSTI]

A cyclic process for controlling environmental emissions of volatile organic compounds (VOC) from vapor recovery in storage and dispensing operations of liquids maintains a vacuum in the storage tank ullage. In one of a two-part cyclic process ullage vapor is discharged through a vapor recovery system in which VOC are stripped from vented gas with a selectively gas permeable membrane. In the other part, the membrane is inoperative while gas pressure rises in the ullage. Ambient air is charged to the membrane separation unit during the latter part of the cycle.

Bowser, John

2004-04-13T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Cyclic membrane separation process  

DOE Patents [OSTI]

A cyclic process for controlling environmental emissions of volatile organic compounds (VOC) from vapor recovery in storage and dispensing operations of liquids maintains a vacuum in the storage tank ullage. In the first part of a two-part cyclic process ullage vapor is discharged through a vapor recovery system in which VOC are stripped from vented gas with a selectively gas permeable membrane. In the second part, the membrane is inoperative while gas pressure rises in the ullage. In one aspect of this invention, a vacuum is drawn in the membrane separation unit thus reducing overall VOC emissions.

Nemser, Stuart M.

2005-05-03T23:59:59.000Z

422

Composite metal membrane  

DOE Patents [OSTI]

A composite metal membrane including a first metal layer of Group IVB met or Group VB metals, the first metal layer sandwiched between two layers of an oriented metal of palladium, platinum or alloys thereof is provided together with a process for the recovery of hydrogen from a gaseous mixture including contacting a hydrogen-containing gaseous mixture with a first side of a nonporous composite metal membrane including a first metal of Group IVB metals or Group VB metals, the first metal layer sandwiched between two layers of an oriented metal of palladium, platinum or alloys thereof, and, separating hydrogen from a second side of the nonporous composite metal membrane.

Peachey, Nathaniel M. (Espanola, NM); Dye, Robert C. (Los Alamos, NM); Snow, Ronny C. (Los Alamos, NM); Birdsell, Stephan A. (Los Alamos, NM)

1998-01-01T23:59:59.000Z

423

Composite metal membrane  

DOE Patents [OSTI]

A composite metal membrane including a first metal layer of Group IVB met or Group VB metals, the first metal layer sandwiched between two layers of an oriented metal of palladium, platinum or alloys thereof is provided together with a process for the recovery of hydrogen from a gaseous mixture including contacting a hydrogen-containing gaseous mixture with a first side of a nonporous composite metal membrane including a first metal of Group IVB metals or Group VB metals, the first metal layer sandwiched between two layers of an oriented metal of palladium, platinum or alloys thereof, and, separating hydrogen from a second side of the nonporous composite metal membrane.

Peachey, N.M.; Dye, R.C.; Snow, R.C.; Birdsell, S.A.

1998-04-14T23:59:59.000Z

424

Rotating bubble membrane radiator  

DOE Patents [OSTI]

A heat radiator useful for expelling waste heat from a power generating system aboard a space vehicle is disclosed. Liquid to be cooled is passed to the interior of a rotating bubble membrane radiator, where it is sprayed into the interior of the bubble. Liquid impacting upon the interior surface of the bubble is cooled and the heat radiated from the outer surface of the membrane. Cooled liquid is collected by the action of centrifical force about the equator of the rotating membrane and returned to the power system. Details regarding a complete space power system employing the radiator are given.

Webb, Brent J. (West Richland, WA); Coomes, Edmund P. (West Richland, WA)

1988-12-06T23:59:59.000Z

425

Calcium-Mediated Regulation of Proton-Coupled Sodium Transport - Final Report  

SciTech Connect (OSTI)

The long-term goal of our experiments was to understand mechanisms that regulate energy coupling by ion currents in plants. Activities of living organisms require chemical, mechanical, osmotic or electrical work, the energy for which is supplied by metabolism. Adenosine triphosphate (ATP) has long been recognized as the universal energy currency, with metabolism supporting the synthesis of ATP and the hydrolysis of ATP being used for the subsequent work. However, ATP is not the only energy currency in living organisms. A second and very different energy currency links metabolism to work by the movement of ions passing from one side of a membrane to the other. These ion currents play a major role in energy capture and they support a range of physiological processes from the active transport of nutrients to the spatial control of growth and development. In Arabidopsis thaliana (Arabidopsis), the activity of a plasma membrane Na+/H+ exchanger, SALT OVERLY SENSITIVE1 (SOS1), is essential for regulation of sodium ion homeostasis during plant growth in saline conditions. Mutations in SOS1 result in severely reduced seedling growth in the presence of salt compared to the growth of wild type. SOS1 is a secondary active transporter coupling movement of sodium ions out of the cell using energy stored in the transplasma membrane proton gradient, thereby preventing the build-up of toxic levels of sodium in the cytosol. SOS1 is regulated by complexes containing the SOS2 and CALCINEURIN B-LIKE10 (CBL10) or SOS3 proteins. CBL10 and SOS3 (also identified as CBL4) encode EF-hand calcium sensors that interact physically with and activate SOS2, a serine/threonine protein kinase. The CBL10/SOS2 or SOS3/SOS2 complexes then activate SOS1 Na+/H+ exchange activity. We completed our studies to understand how SOS1 activity is regulated. Specifically, we asked: (1) how does CBL10 regulate SOS1 activity? (2) What role do two putative CBL10-interacting proteins play in SOS1 regulation? (3) Are there differences in the regulation and/or activity of SOS1 in plants differing in their adaptation to salinity?

Schumaker, Karen S [Professor] [Professor

2013-10-24T23:59:59.000Z

426

Design and characterization of a neutralized-transport experiment for heavy-ion fusion Enrique Henestroza, Shmuel Eylon, Prabir K. Roy, Simon S. Yu, Andre Anders, Frank M. Bieniosek,  

E-Print Network [OSTI]

to hit spots on the target with radii of about 2 mm. For the heavy-ion-fusion power-plant scenarios comparisons of these theoretical predictions with experiment, the Virtual National Laboratory for Heavy Ion

Gilson, Erik

427

Ion Colliders  

E-Print Network [OSTI]

High-energy ion colliders are large research tools in nuclear physics to study the Quark-Gluon-Plasma (QGP). The range of collision energy and high luminosity are important design and operational considerations. The experiments also expect flexibility with frequent changes in the collision energy, detector fields, and ion species. Ion species range from protons, including polarized protons in RHIC, to heavy nuclei like gold, lead and uranium. Asymmetric collision combinations (e.g. protons against heavy ions) are also essential. For the creation, acceleration, and storage of bright intense ion beams, limits are set by space charge, charge change, and intrabeam scattering effects, as well as beam losses due to a variety of other phenomena. Currently, there are two operating ion colliders, the Relativistic Heavy Ion Collider (RHIC) at BNL, and the Large Hadron Collider (LHC) at CERN.

Fischer, W

2015-01-01T23:59:59.000Z

428

Wrinkling in polygonal membranes  

E-Print Network [OSTI]

boundary conditions of the polygons. When pressurised, the polygonal membranes naturally reach a parabolic shape towards their centre, the extent of which varies greatly depending on a large number of parameters, including most particularly pre...

Bonin, Arnaud Stephane

2012-02-07T23:59:59.000Z

429

Gas Separation Using Membranes  

E-Print Network [OSTI]

Commercial membrane-based gas separator systems based upon high-flux, asymmetric polysulfone hollow fibers were first introduced in 1977 by Monsanto. These systems were packaged in compact modules containing large amounts of permeation surface area...

Koros, W. J.; Paul, D. R.

1984-01-01T23:59:59.000Z

430

Membrane separation of hydrocarbons  

DOE Patents [OSTI]

Mixtures of heavy oils and light hydrocarbons may be separated by passing the mixture over a polymeric membrane which comprises a polymer capable of maintaining its integrity in the presence of hydrocarbon compounds at temperature ranging from about ambient to about 100.degree. C. and pressures ranging from about 50 to about 1000 psi. The membranes which possess pore sizes ranging from about 10 to about 500 Angstroms are cast from a solvent solution and recovered.

Funk, Edward W. (Highland Park, IL); Kulkarni, Sudhir S. (Hoffman Estates, IL); Chang, Y. Alice (Des Plaines, IL)

1986-01-01T23:59:59.000Z

431

Membrane reference electrode  

DOE Patents [OSTI]

A reference electrode utilizes a small thin, flat membrane of a highly conductive glass placed on a small diameter insulator tube having a reference material inside in contact with an internal voltage lead. When the sensor is placed in a non-aqueous ionic electrolytic solution, the concentration difference across the glass membrane generates a low voltage signal in precise relationship to the concentration of the species to be measured, with high spatial resolution. 2 figs.

Redey, L.; Bloom, I.D.

1988-01-21T23:59:59.000Z

432

Microprobes aluminosilicate ceramic membranes  

DOE Patents [OSTI]

Methods have been developed to make mixed alumina-silicate and aluminosilicate particulate microporous ceramic membranes. One method involves the making of separate alumina and silica sols which are then mixed. Another method involves the creation of a combined sol with aluminosilicate particles. The resulting combined alumina and silica membranes have high surface area, a very small pore size, and a very good temperature stability.

Anderson, Marc A. (2114 Chadbourne Ave., Madison, WI 53705); Sheng, Guangyao (45 N. Orchard St., Madison, WI 53715)

1993-01-01T23:59:59.000Z

433

High Temperature Membrane Working Group  

Broader source: Energy.gov [DOE]

This presentation provides an overview of the High Temperature Membrane Working Group Meeting in May 2007.

434

Free-standing graphene membranes on glass nanopores for ionic current measurements  

E-Print Network [OSTI]

A method is established to reliably suspend graphene monolayers across glass nanopores as a simple, low cost platform to study ionic transport through graphene membranes. We systematically show that the graphene seals glass nanopore openings...

Walker, Michael I.; Weatherup, Robert S.; Bell, Nicholas A. W.; Hofmann, Stephan; Keyser, Ulrich F.

2015-01-16T23:59:59.000Z

435

Sequestration and Transport of Lignin Monomeric Precursors  

SciTech Connect (OSTI)

Lignin is the second most abundant terrestrial biopolymer after cellulose. It is essential for the viability of vascular plants. Lignin precursors, the monolignols, are synthesized within the cytosol of the cell. Thereafter, these monomeric precursors are exported into the cell wall, where they are polymerized and integrated into the wall matrix. Accordingly, transport of monolignols across cell membranes is a critical step affecting deposition of lignin in the secondarily thickened cell wall. While the biosynthesis of monolignols is relatively well understood, our knowledge of sequestration and transport of these monomers is sketchy. In this article, we review different hypotheses on monolignol transport and summarize the recent progresses toward the understanding of the molecular mechanisms underlying monolignol sequestration and transport across membranes. Deciphering molecular mechanisms for lignin precursor transport will support a better biotechnological solution to manipulate plant lignification for more efficient agricultural and industrial applications of cell wall biomass.

Liu, C.J.; Miao, Y.-C.; Zhang, K.-W.

2011-01-18T23:59:59.000Z

436

Inorganic membranes: The new industrial revolution  

SciTech Connect (OSTI)

Separation systems are a vital part of most industrial processes. These systems account for a large fraction of the capital equipment used and the operating costs of industrial processes. Inorganic membranes have the potential for providing separation systems that can significantly reduce both the capital equipment and operating costs. These separation processes include waste management and recycle as well as the primary production of raw materials and products. The authors are rapidly learning to understand the effect of physical and chemical properties on the different transport mechanisms that occur in inorganic membranes. Such understanding can be expected to provide the information needed to design, engineer and manufacture inorganic membranes to produce very high separation factors for almost any separation function. To implement such a revolution, the authors need to organize a unique partnership between the national laboratories, and industry. The university can provide research to understand the materials and transport mechanisms that produce various separations, the national laboratories the development of an economical fabrication and manufacturing capability, and industry the practical understanding of the operational problems required to achieve inplementation.

Fain, D.E. [Martin Merietta Energy Systems, Oak Ridge, TN (United States)

1994-12-31T23:59:59.000Z

437

Silver transport in CVD silicon carbide  

E-Print Network [OSTI]

Ion implantation and diffusion couple experiments were used to study silver transport through and release from CVD silicon carbide. Results of these experiments show that silver does not migrate via classical diffusion in ...

MacLean, Heather J. (Heather Jean), 1974-

2004-01-01T23:59:59.000Z

438

Membrane Applications at Ceramatec  

Broader source: Energy.gov (indexed) [DOE]

at Ceramatec Solid Electrolyte Ion Conductors CO 2 to Syngas GTL Advanced Batteries oxygen Fluorine Hydrogen Alkali metals Specialty Chemicals Waste Remediation Disinfection...

439

Q1Report for CADWR Project: Desalination Using Carbon NAnotube Membranes  

SciTech Connect (OSTI)

In this research and development project, LLNL will leverage the process for fabrication of the membranes developed by our internally funded effort (LLNL Laboratory Directed Research and Development). LLNL will then employ chemical manipulations to modify charge at the ends of the nanotubes and make the membranes more selective to either positive or negative ions through a combination of size and charge selectivity. LLNL's goal is to demonstrate ion exclusion while preserving high permeabilities and low energy use. Success of this research and development project may warrant further developments in the fabrication of membranes.

Bakajin, O

2008-05-14T23:59:59.000Z

440

Transport Reactor Development Unit Modification to Provide a Syngas Slipstream at Elevated Conditions to Enable Separation of 100 LB/D of Hydrogen by Hydrogen Separation Membranes Year - 6 Activity 1.15 - Development of a National Center for Hydrogen Technology  

SciTech Connect (OSTI)

Gasification of coal when associated with carbon dioxide capture and sequestration has the potential to provide low-cost as well as low-carbon hydrogen for electric power, fuels or chemicals production. The key element to the success of this concept is inexpensive, effective separation of hydrogen from carbon dioxide in synthesis gas. Many studies indicate that membrane technology is one of the most, if not the most, economical means of accomplishing separation; however, the advancement of hydrogen separation membrane technology is hampered by the absence of experience or demonstration that the technology is effective economically and environmentally at larger scales. While encouraging performance has been observed at bench scale (less than 12 lb/d hydrogen), it would be imprudent to pursue a largescale demonstration without testing at least one intermediate scale, such as 100 lb/d hydrogen. Among its many gasifiers, the Energy & Environmental Research Center is home to the transport reactor demonstration unit (TRDU), a unit capable of firing 200500 lb/hr of coal to produce 400 scfm of synthesis gas containing more than 200 lb/d of hydrogen. The TRDU and associated downstream processing equipment has demonstrated the capability of producing a syngas over a wide range of temperatures and contaminant levels some of which approximate conditions of commercial-scale gasifiers. Until this activity, however, the maximum pressure of the TRDU s product syngas was 120 psig, well below the 400+ psig pressures of existing large gasifiers. This activity installed a high-temperature compressor capable of accepting the range of TRDU products up to 450F and compressing them to 500 psig, a pressure comparable to some large scale gasifiers. Thus, with heating or cooling downstream of the TRDU compressor, the unit is now able to present a near-raw to clean gasifier synthesis gas containing more than 100 lb/d of hydrogen at up to 500 psig over a wide range of temperatures to hydrogen separation membranes or other equipment for development and demonstration.

Schlasner, Steven

2012-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "ion transport membrane" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

An ultra-thin diamond membrane as a transmission particle detector and vacuum window for external microbeams  

SciTech Connect (OSTI)

Several applications of external microbeam techniques demand a very accurate and controlled dose delivery. To satisfy these requirements when post-sample ion detection is not feasible, we constructed a transmission single-ion detector based on an ultra-thin diamond membrane. The negligible intrinsic noise provides an excellent signal-to-noise ratio and enables a hit-detection efficiency of close to 100%, even for energetic protons, while the small thickness of the membrane limits beam spreading. Moreover, because of the superb mechanical stiffness of diamond, this membrane can simultaneously serve as a vacuum window and allow the extraction of an ion microbeam into the atmosphere.

Grilj, V.; Skukan, N.; Jaki?, M. [Division of Experimental Physics, Ru?er Bokovi? Institute, 10000 Zagreb (Croatia)] [Division of Experimental Physics, Ru?er Bokovi? Institute, 10000 Zagreb (Croatia); Pomorski, M. [CEA-LIST, Diamond Sensors Laboratory, Gif-sur-Yvette F-91191 (France)] [CEA-LIST, Diamond Sensors Laboratory, Gif-sur-Yvette F-91191 (France); Kada, W. [Division of Electronics and Informatics, Faculty of Science and Technology, Gunma University, Kiryu, Gunma 376-8515 (Japan)] [Division of Electronics and Informatics, Faculty of Science and Technology, Gunma University, Kiryu, Gunma 376-8515 (Japan); Iwamoto, N.; Kamiya, T.; Ohshima, T. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency (JAEA), Takasaki, Gunma 370-1292 (Japan)] [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency (JAEA), Takasaki, Gunma 370-1292 (Japan)

2013-12-09T23:59:59.000Z

442

EMSL - ions  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

ions en Reorientation of the free OH group in the top-most layer of airwater interface of sodium fluoride aqueous http:www.emsl.pnl.govemslwebpublications...

443

Hydrogen separation membranes annual report for FY 2006.  

SciTech Connect (OSTI)

The objective of this work is to develop dense ceramic membranes for separating hydrogen from other gaseous components in a nongalvanic mode, i.e., without using an external power supply or electrical circuitry. This goal of this project is to develop two types of dense ceramic membrane for producing hydrogen nongalvanically, i.e., without electrodes or external power supply, at commercially significant fluxes under industrially relevant operating conditions. The first type of membrane, hydrogen transport membranes (HTMs), will be used to separate hydrogen from gas mixtures such as the product streams from coal gasification, methane partial oxidation, and water-gas shift reactions. Potential ancillary uses of HTMs include dehydrogenation and olefin production, as well as hydrogen recovery in petroleum refineries and ammonia synthesis plants, the largest current users of deliberately produced hydrogen. The second type of membrane, oxygen transport membranes (OTMs), will produce hydrogen by nongalvanically removing oxygen that is generated when water dissociates at elevated temperatures. This report describes progress that was made during FY 2006 on the development of OTM and HTM materials.

Balachandran, U.; Chen, L.; Ciocco, M.; Doctor, R. D.; Dorris, S.E.; Emerson, J. E.; Fisher, B.; Lee, T. H.; Killmeyer, R. P.; Morreale,B.; Picciolo, J. J.; Siriwardane, R. V.; Song, S. J.

2007-02-05T23:59:59.000Z

444

CENTRIFUGAL MEMBRANE FILTRATION  

SciTech Connect (OSTI)

SpinTek Membrane Systems, Inc., the developer of a centrifugal membrane filtration technology, has engineered and developed a system for use within the U.S. Department of Energy (DOE) Environmental Management (EM) Program. The technology uses supported microporous membranes rotating at high rpm, under pressure, to separate suspended and colloidal solids from liquid streams, yielding a solids-free permeate stream and a highly concentrated solids stream. This is a crosscutting technology that falls under the Efficient Separations and Processing Crosscutting Program, with potential application to tank wastes, contaminated groundwater, landfill leachate, and secondary liquid waste streams from other remediation processes, including decontamination and decommissioning systems. SpinTek II High Shear Rotary Membrane Filtration System is a unique compact crossflow membrane system that has large, demonstrable advantages in performance and cost compared to currently available systems: (1) High fluid shear prevents membrane fouling even with very high solids content; hazardous and radioactive components can be concentrated to the consistency of a pasty slurry without fouling. (2) Induced turbulence and shear across the membrane increases membrane flux by a factor of ten over existing systems and allows operation on fluids not otherwise treatable. (3) Innovative ceramic membrane and mechanical sealing technology eliminates compatibility problems with aggressive DOE waste streams. (4) System design allows rapid, simple disassembly for inspection or complete decontamination. (5) Produces colloidal- and suspended-solids-free filtrate without the addition of chemicals. The first phase of this project (PRDA maturity stage 5) completed the physical scale-up of the SpinTek unit and verified successful scale-up with surrogate materials. Given successful scale-up and DOE concurrence, the second phase of this project (PRDA maturity stage 6) will provide for the installation and operation of the full-scale two-stage SpinTek unit for treatment of a DOE waste-stream at the Los Alamos National Laboratory. This technology has very broad application across the DOE system. Nineteen DOE technical needs areas (Appendix C) have been identified. Following successful full-scale demonstration for treatment of DOE wastes, this innovative technology will be rapidly deployed on a wide range of waste and process streams throughout the DOE system.

William A. Greene; Patricia A. Kirk; Richard Hayes; Joshua Riley

2005-10-28T23:59:59.000Z

445

The Metal-dependent Function of C2?: A Conditional Membrane Domain from Protein Kinase C?  

E-Print Network [OSTI]

), which associates with anionic membranes in response to binding Ca^(2+) ions in the first step of activation. The objective of this work was to determine the specific role of divalent metal ions on the modulation of C2alpha structure, function...

Morales-Rivera, Krystal A.

2013-11-26T23:59:59.000Z

446

Systems and methods for selective hydrogen transport and measurement  

DOE Patents [OSTI]

Systems and methods for selectively removing hydrogen gas from a hydrogen-containing fluid volume are disclosed. An exemplary system includes a proton exchange membrane (PEM) selectively permeable to hydrogen by exclusively conducting hydrogen ions. The system also includes metal deposited as layers onto opposite sides or faces of the PEM to form a membrane-electrode assembly (MEA), each layer functioning as an electrode so that the MEA functions as an electrochemical cell in which the ionic conductors are hydrogen ions, and the MEA functioning as a hydrogen selective membrane (HSM) when located at the boundary between a hydrogen-containing fluid volume and a second fluid.

Glatzmaier, Gregory C

2013-10-29T23:59:59.000Z

447

Development of novel active transport membrande devices  

SciTech Connect (OSTI)

Air Products has undertaken a research program to fabricate and evaluate gas separation membranes based upon promising ``active-transport`` (AT) materials recently developed in our laboratories. Active Transport materials are ionic polymers and molten salts which undergo reversible interaction or reaction with ammonia and carbon dioxide. The materials are useful for separating these gases from mixtures with hydrogen. Moreover, AT membranes have the unique property of possessing high permeability towards ammnonia and carbon dioxide but low permeability towards hydrogen and can thus be used to permeate these components from a gas stream while retaining hydrogen at high pressure.

Laciak, D.V.

1994-11-01T23:59:59.000Z

448

Supported microporous ceramic membranes  

DOE Patents [OSTI]

A method for permformation of microporous ceramic membranes onto a porous support includes placing a colloidal suspension of metal or metal oxide particles on one side of the porous support and exposing the other side of the porous support to a drying stream of gas or a reactive gas stream so that the particles are deposited on the drying side of the support as a gel. The gel so deposited can be sintered to form a supported ceramic membrane useful for ultrafiltration, reverse osmosis, or molecular sieving having mean pore sizes less than 100 Angstroms.

Webster, Elizabeth (Madison, WI); Anderson, Marc (Madison, WI)

1993-01-01T23:59:59.000Z

449

Supported microporous ceramic membranes  

DOE Patents [OSTI]

A method for the formation of microporous ceramic membranes onto a porous support includes placing a colloidal suspension of metal or metal oxide particles on one side of the porous support and exposing the other side of the porous support to a drying stream of gas or a reactive gas stream so that the particles are deposited on the drying side of the support as a gel. The gel so deposited can be sintered to form a supported ceramic membrane useful for ultrafiltration, reverse osmosis, or molecular sieving having mean pore sizes less than 100 Angstroms. 4 figures.

Webster, E.; Anderson, M.

1993-12-14T23:59:59.000Z

450

Advanced Materials for Proton Exchange Membranes | Department...  

Broader source: Energy.gov (indexed) [DOE]

Advanced Materials for Proton Exchange Membranes Advanced Materials for Proton Exchange Membranes A presentation to the High Temperature Membranes Working Group meeting, May 19,...

451