Sample records for na-sg sodium silica

  1. Synthesis of highly ordered mesoporous silica materials using sodium silicate and amphiphilic block copolymers

    E-Print Network [OSTI]

    Kim, Ji Man

    Synthesis of highly ordered mesoporous silica materials using sodium silicate and amphiphilic block) structures, using sodium silicate as the silica source and amphiphilic block copolymers as the structure of mesoporous silica material using nonionic surfac- tant and sodium silicate in the pH range 3­10.5. However

  2. CX-000207: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    NaSi (Sodium Silicide) and Na-SG (Sodium Silica Gell) Powder Hydrogen Fuel CellsCX(s) Applied: B3.6Date: 11/23/2009Location(s): New YorkOffice(s): Energy Efficiency and Renewable Energy, Golden Field Office

  3. Kinetics of silica polymerization

    SciTech Connect (OSTI)

    Weres, O.; Yee, A.; Tsao, L.

    1980-05-01T23:59:59.000Z

    The polymerization of silicic acid in geothermal brine-like aqueous solutions to produce amorphous silica in colloidal form has been studied experimentally and theoretically. A large amount of high quality experimental data has been generated over the temperature rang 23 to 100{sup 0}C. Wide ranges of dissolved silica concentration, pH, and sodium chloride concentration were covered. The catalytic effects of fluoride and the reaction inhibiting effects of aluminum and boron were studied also. Two basic processes have been separately studied: the formation of new colloidal particles by the homogeneous nucleation process and the deposition of dissolved silica on pre-existing colloidal particles. A rigorous theory of the formation of colloidal particles of amorphous silica by homogeneous nucleation was developed. This theory employs the Lothe-Pound formalism, and is embodied in the computer code SILNUC which quantitatively models the homogeneous nucleation and growth of colloidal silica particles in more than enough detail for practical application. The theory and code were extensively used in planning the experimental work and analyzing the data produced. The code is now complete and running in its final form. It is capable of reproducing most of the experimental results to within experimental error. It is also capable of extrapolation to experimentally inaccessible conditions, i.e., high temperatures, rapidly varying temperature and pH, etc.

  4. Silica Scaling Removal Process

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

    sidestreams of cooling tower water by providing a substrate for the deposition and adsorption of silica. The removal of the silica prevents scaling deposition on heat transfer...

  5. Kinetics of Silica Polymerization

    E-Print Network [OSTI]

    Weres, Oleh

    2011-01-01T23:59:59.000Z

    geothermal brines:’ Avoidance or minimization of silica supersaturation Supersaturation can be avoided by preventing cooling

  6. Silica extraction from geothermal water

    DOE Patents [OSTI]

    Bourcier, William L; Bruton, Carol J

    2014-09-23T23:59:59.000Z

    A method of producing silica from geothermal fluid containing low concentration of the silica of less than 275 ppm includes the steps of treating the geothermal fluid containing the silica by reverse osmosis treatment thereby producing a concentrated fluid containing the silica, seasoning the concentrated fluid thereby producing a slurry having precipitated colloids containing the silica, and separating the silica from the slurry.

  7. Silica in Protoplanetary Disks

    E-Print Network [OSTI]

    B. A. Sargent; W. J. Forrest; C. Tayrien; M. K. McClure; A. Li; A. R. Basu; P. Manoj; D. M. Watson; C. J. Bohac; E. Furlan; K. H. Kim; J. D. Green; G. C. Sloan

    2008-11-21T23:59:59.000Z

    Mid-infrared spectra of a few T Tauri stars (TTS) taken with the Infrared Spectrograph (IRS) on board the Spitzer Space Telescope show prominent narrow emission features indicating silica (crystalline silicon dioxide). Silica is not a major constituent of the interstellar medium; therefore, any silica present in the circumstellar protoplanetary disks of TTS must be largely the result of processing of primitive dust material in the disks surrouding these stars. We model the silica emission features in our spectra using the opacities of various polymorphs of silica and their amorphous versions computed from earth-based laboratory measurements. This modeling indicates that the two polymorphs of silica, tridymite and cristobalite, which form at successively higher temperatures and low pressures, are the dominant forms of silica in the TTS of our sample. These high temperature, low pressure polymorphs of silica present in protoplanetary disks are consistent with a grain composed mostly of tridymite named Ada found in the cometary dust samples collected from the STARDUST mission to Comet 81P/Wild 2. The silica in these protoplanetary disks may arise from incongruent melting of enstatite or from incongruent melting of amorphous pyroxene, the latter being analogous to the former. The high temperatures of 1200K-1300K and rapid cooling required to crystallize tridymite or cristobalite set constraints on the mechanisms that could have formed the silica in these protoplanetary disks, suggestive of processing of these grains during the transient heating events hypothesized to create chondrules.

  8. Sodium Titanate Anodes for Sodium Ion Batteries

    E-Print Network [OSTI]

    Doeff, Marca M.

    2014-01-01T23:59:59.000Z

    for  Sodium  Ion  Batteries   One   of   the   challenges  of   sodium   ion   batteries   is   identification   of  for   use   in   batteries.   Our   recent   work   has  

  9. Atomistic structure of sodium and calcium silicate intergranular films in alumina

    E-Print Network [OSTI]

    Garofalini, Stephen H.

    Atomistic structure of sodium and calcium silicate intergranular films in alumina David A. Litton March 1998; accepted 21 October 1998) Sodium silicate intergranular films (IGF) in contact. The results were compared to previous simulations of calcium silicate and sol-gel silica IGF's in contact

  10. Kinetics of Silica Polymerization

    E-Print Network [OSTI]

    Weres, Oleh

    2011-01-01T23:59:59.000Z

    The Chemistry of Silica in Cerro Prieto Brines". Report LBL-the United States, Cerro Prieto and n Mexico, and WairakeiProgram .of DGE through the Cerro Prieto Research Project at

  11. Sodium Titanates as Anodes for Sodium Ion Batteries

    E-Print Network [OSTI]

    Doeff, Marca M.

    2014-01-01T23:59:59.000Z

    Anodes  for  Sodium  Ion  Batteries   Marca  M.  Doeff,  dual   intercalation   batteries   based   on   sodium  future   of   sodium  ion  batteries  will  be  discussed  

  12. Electron-Irradiation Induced Nanocrystallization of Pb(II) in Silica Gels Prepared in High Magnetic Field

    E-Print Network [OSTI]

    Kaito, Takamasa; Kaito, Chihiro

    2015-01-01T23:59:59.000Z

    In a previous study, structure of silica gels prepared in a high magnetic field was investigated. While a direct application of such anisotropic silica gels is for an optical anisotropic medium possessing chemical resistance, we show here their possibility of medium in materials processing. In this direction, for example, silica hydrogels have so far been used as media of crystal growth. In this paper, as opposed to the soft-wet state, dried silica gels have been investigated. We have found that lead (II) nanocrystallites were formed induced by electron irradiation to lead (II)-doped dried silica gels prepared in a high magnetic field such as B = 10 T. Hydrogels made from a sodium metasilicate solution doped with lead (II) acetate were prepared. The dried specimens were irradiated by electrons in a transmission electron microscope environment. Electron diffraction patterns indicated the crystallinity of lead (II) nanocrystallites depending on B. An advantage of this processing technique is that the crystallin...

  13. Submersible sodium pump

    DOE Patents [OSTI]

    Brynsvold, G.V.; Lopez, J.T.; Olich, E.E.; West, C.W.

    1989-11-21T23:59:59.000Z

    An electromagnetic submerged pump has an outer cylindrical stator with an inner cylindrical conductive core for the submerged pumping of sodium in the cylindrical interstitial volume defined between the stator and core. The cylindrical interstitial volume is typically vertically oriented, and defines an inlet at the bottom and an outlet at the top. The outer stator generates upwardly conveyed toroidal magnetic fields, which fields convey preferably from the bottom of the pump to the top of the pump liquid sodium in the cold leg of a sodium cooled nuclear reactor. The outer cylindrical stator has a vertically disposed duct surrounded by alternately stacked layers of coil units and laminates. 14 figs.

  14. Continuous process preparation of activated silica with low carbon dioxide content gas

    E-Print Network [OSTI]

    Burdett, Joseph Walton

    1954-01-01T23:59:59.000Z

    Iiroduced. Activated silica is the term used to designate a negatively charged colloidal particle formed by the reactien of a dilute sodium silicate solution with a dilute solution of' an acidic material or other activant. Used as a coagulant sid to alum.... paylis (5) at Chicago found that, sodium silicate could. 'be used with paper maker's alum (aluminum sulfate) as an effective c~t aid. in treating Lake l4. chigan water. Since that time several. batch processes have been cleveloyed using various...

  15. Detection of alkali-silica reaction swelling in concrete by staining

    DOE Patents [OSTI]

    Guthrie, G.D. Jr.; Carey, J.W.

    1998-04-14T23:59:59.000Z

    A method using concentrated aqueous solutions of sodium cobalt nitrite and rhodamine B is described which can be used to identify concrete that contains gels formed by the alkali-silica reaction (ASR). These solutions present little health or environmental risk, are readily applied, and rapidly discriminate between two chemically distinct gels; K-rich, Na-K-Ca-Si gels are identified by yellow staining, and alkali-poor, Ca-Si gels are identified by pink staining.

  16. Detection of alkali-silica reaction swelling in concrete by staining

    DOE Patents [OSTI]

    Guthrie, Jr., George D. (Santa Fe, NM); Carey, J. William (Santa Fe, NM)

    1998-01-01T23:59:59.000Z

    A method using concentrated aqueous solutions of sodium cobaltinitrite and rhodamine B is described which can be used to identify concrete that contains gels formed by the alkali-silica reaction (ASR). These solutions present little health or environmental risk, are readily applied, and rapidly discriminate between two chemically distinct gels; K-rich, Na--K--Ca--Si gels are identified by yellow staining, and alkali-poor, Ca--Si gels are identified by pink staining.

  17. Removal of dissolved and colloidal silica

    DOE Patents [OSTI]

    Midkiff, William S. (Ruidoso, NM)

    2002-01-01T23:59:59.000Z

    Small amorphous silica particles are used to provide a relatively large surface area upon which silica will preferentially adsorb, thereby preventing or substantially reducing scaling caused by deposition of silica on evaporative cooling tower components, especially heat exchange surfaces. The silica spheres are contacted by the cooling tower water in a sidestream reactor, then separated using gravity separation, microfiltration, vacuum filtration, or other suitable separation technology. Cooling tower modifications for implementing the invention process have been designed.

  18. Stabilized fuel with silica support structure

    SciTech Connect (OSTI)

    Poco, J.F.; Hrubesh, L.W.

    1991-12-31T23:59:59.000Z

    This report describes a stabilized fuel which is supported by a silica support structure. The silica support structure provides a low density, high porosity vehicle for safely carrying hydrocarbon fuels. The silica support structure for hydrocarbon fuel does not produce toxic material residues on combustion which would pose environmentally sensitive disposal problems. The silica stabilized fuel composition is useful as a low temperature, continuous burning fire starter for wood or charcoal.

  19. Titanate Anodes for Sodium Ion Batteries

    E-Print Network [OSTI]

    Doeff, Marca M.

    2014-01-01T23:59:59.000Z

    Anodes for Sodium Ion Batteries Identification of a suitabledevelopment of sodium ion batteries, because graphite, theanode for lithium ion batteries, does not undergo sodium

  20. Cellular membrane trafficking of mesoporous silica nanoparticles

    SciTech Connect (OSTI)

    Fang, I-Ju

    2012-06-21T23:59:59.000Z

    This dissertation mainly focuses on the investigation of the cellular membrane trafficking of mesoporous silica nanoparticles. We are interested in the study of endocytosis and exocytosis behaviors of mesoporous silica nanoparticles with desired surface functionality. The relationship between mesoporous silica nanoparticles and membrane trafficking of cells, either cancerous cells or normal cells was examined. Since mesoporous silica nanoparticles were applied in many drug delivery cases, the endocytotic efficiency of mesoporous silica nanoparticles needs to be investigated in more details in order to design the cellular drug delivery system in the controlled way. It is well known that cells can engulf some molecules outside of the cells through a receptor-ligand associated endocytosis. We are interested to determine if those biomolecules binding to cell surface receptors can be utilized on mesoporous silica nanoparticle materials to improve the uptake efficiency or govern the mechanism of endocytosis of mesoporous silica nanoparticles. Arginine-glycine-aspartate (RGD) is a small peptide recognized by cell integrin receptors and it was reported that avidin internalization was highly promoted by tumor lectin. Both RGD and avidin were linked to the surface of mesoporous silica nanoparticle materials to investigate the effect of receptor-associated biomolecule on cellular endocytosis efficiency. The effect of ligand types, ligand conformation and ligand density were discussed in Chapter 2 and 3. Furthermore, the exocytosis of mesoporous silica nanoparticles is very attractive for biological applications. The cellular protein sequestration study of mesoporous silica nanoparticles was examined for further information of the intracellular pathway of endocytosed mesoporous silica nanoparticle materials. The surface functionality of mesoporous silica nanoparticle materials demonstrated selectivity among the materials and cancer and normal cell lines. We aimed to determine the specific organelle that mesoporous silica nanoparticles could approach via the identification of harvested proteins from exocytosis process. Based on the study of endo- and exocytosis behavior of mesoporous silica nanoparticle materials, we can design smarter drug delivery vehicles for cancer therapy that can be effectively controlled. The destination, uptake efficiency and the cellular distribution of mesoporous silica nanoparticle materials can be programmable. As a result, release mechanism and release rate of drug delivery systems can be a well-controlled process. The deep investigation of an endo- and exocytosis study of mesoporous silica nanoparticle materials promotes the development of drug delivery applications.

  1. Chemistry of Silica in Cerro Prieto Brines

    E-Print Network [OSTI]

    Weres, Oleh

    2012-01-01T23:59:59.000Z

    LBL-10166 CERRO-PRIETO-12 XICAN-AMERICANCOOPERATIVE' PROGRAM T THE CERRO PRIETO GEOTHERMAL FIELD ICHEMISTRY OF SILICA IN CERRO PRIETO BRINES Oleh Weres Leon

  2. Chemistry of Silica in Cerro Prieto Brines

    E-Print Network [OSTI]

    Weres, O.

    2010-01-01T23:59:59.000Z

    LBL-10166 CERRO-PRIETO-12 XICAN-AMERICANCOOPERATIVE' PROGRAM T THE CERRO PRIETO GEOTHERMAL FIELD ICHEMISTRY OF SILICA IN CERRO PRIETO BRINES Oleh Weres Leon

  3. Silica Supported Ceria Nanoparticles: A Hybrid Nanostructure...

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

    The surface chemical and vibrational spectroscopy analysis revealed cerium–silicate (Ce-O-Si) covalent bond linkage between silica and cerium oxide nanoparticles. The...

  4. Red-luminescent europium (III) doped silica nanoshells: synthesis,

    E-Print Network [OSTI]

    Kummel, Andrew C.

    Red-luminescent europium (III) doped silica nanoshells: synthesis, characterization(6), 066012 (June 2011) Red-luminescent europium (III) doped silica nanoshells: synthesis, characterization (SPIE). [DOI: 10.1117/1.3593003] Keywords: europium; silica; luminescent; nanoshells; endocytosis. Paper

  5. Synthesis of supported carbon nanotubes in mineralized silica...

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

    supported carbon nanotubes in mineralized silica-wood composites. Synthesis of supported carbon nanotubes in mineralized silica-wood composites. Abstract: Multiwall carbon...

  6. Functionalized Nanoporous Silica for Removal of Heavy Metals...

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

    Nanoporous Silica for Removal of Heavy Metals from Biological Systems; Adsorption and Application. Functionalized Nanoporous Silica for Removal of Heavy Metals from Biological...

  7. Templating Mesoporous Hierarchies in Silica Thin Films Using...

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

    Templating Mesoporous Hierarchies in Silica Thin Films Using the Thermal Degradation of Cellulose Nitrate. Templating Mesoporous Hierarchies in Silica Thin Films Using the Thermal...

  8. Synthesis and properties of Chitosan-silica hybrid aerogels

    E-Print Network [OSTI]

    Ayers, Michael R.; Hunt, Arlon J.

    2001-01-01T23:59:59.000Z

    chitosan-silica composite aerogels can be easily synthesizedphysical properties of these aerogels. These materials may1. Top: Chitosan-silica aerogel (sample 4), Bottom: Same

  9. Silica Deposition | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries Pvt LtdShawangunk, New York:SiG Solar GmbH Jump to:SierraMountain,SilentSilica

  10. Controlled release of ibuprofen by meso–macroporous silica

    SciTech Connect (OSTI)

    Santamaría, E., E-mail: esthersantamaria@ub.edu; Maestro, A.; Porras, M.; Gutiérrez, J.M.; González, C.

    2014-02-15T23:59:59.000Z

    Structured meso–macroporous silica was successfully synthesized from an O/W emulsion using decane as a dispersed phase. Sodium silicate solution, which acts as a silica source and a poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) (EO{sub 19}PO{sub 39}EO{sub 19}) denoted as P84 was used in order to stabilize the emulsion and as a mesopore template. The materials obtained were characterized through transmission electron microscopy (TEM), scanning electron microscopy (SEM), small-angle X-ray diffraction scattering (SAXS) and nitrogen adsorption–desorption isotherms. Ibuprofen (IBU) was selected as the model drug and loaded into ordered meso–macroporous materials. The effect of the materials’ properties on IBU drug loading and release was studied. The results showed that the loading of IBU increases as the macropore presence in the material is increased. The IBU adsorption process followed the Langmuir adsorption isotherm. A two-step release process, consisting of an initial fast release and then a slower release was observed. Macropores enhanced the adsorption capacity of the material; this was probably due to the fact that they allowed the drug to access internal pores. When only mesopores were present, ibuprofen was probably adsorbed on the mesopores close to the surface. Moreover, the more macropore present in the material, the slower the release behaviour observed, as the ibuprofen adsorbed in the internal pores had to diffuse along the macropore channels up to the surface of the material. The material obtained from a highly concentrated emulsion was functionalized with amino groups using two methods, the post-grafting mechanism and the co-condensation mechanism. Both routes improve IBU adsorption in the material and show good behaviour as a controlled drug delivery system. - Graphical abstract: Ibuprofen release profiles for the materials obtained from samples P84{sub m}eso (black diamonds), P84{sub 2}0% (white squares), P84{sub 5}0% (black triangles), P84{sub 7}5% (white diamonds), P84{sub 7}5% functionalized by grafting (black squares) and P84{sub 7}5% functionalized by co-condensation method (white triangles). Display Omitted - Highlights: • Ordered meso–macroporous material is used as a controlled delivery system for ibuprofen. • Incorporation of macropores in mesoporous silica improves ibuprofen adsorption. • Meso–macroporous structures provide a lower delivery than mesoporous silica. • APTES functionalization in meso–macroporous materials improves ibuprofen adsorption and delivery behaviour.

  11. Gold Nanoparticle Silica Nanopeapods Vu Thanh Cong,,

    E-Print Network [OSTI]

    Kim, Sehun

    Gold Nanoparticle Silica Nanopeapods Vu Thanh Cong,, Erdene-Ochir Ganbold,§ Joyanta K. Saha gold nanoparticle (AuNP) silica nanotube peapod (SNTP) was fabricated by self-assembly. The geometrical-dependent surface-enhanced Raman scattering (SERS) spectra of bifunctional aromatic linker p-mercaptobenzoic acid (p-MBA)-coated

  12. Sample Desorption/Onization From Mesoporous Silica

    DOE Patents [OSTI]

    Iyer, Srinivas (Los Alamos, NM); Dattelbaum, Andrew M. (Los Alamos, NM)

    2005-10-25T23:59:59.000Z

    Mesoporous silica is shown to be a sample holder for laser desorption/ionization of mass spectrometry. Supported mesoporous silica was prepared by coating an ethanolic silicate solution having a removable surfactant onto a substrate to produce a self-assembled, ordered, nanocomposite silica thin film. The surfactant was chosen to provide a desired pore size between about 1 nanometer diameter and 50 nanometers diameter. Removal of the surfactant resulted in a mesoporous silica thin film on the substrate. Samples having a molecular weight below 1000, such as C.sub.60 and tryptophan, were adsorbed onto and into the mesoporous silica thin film sample holder and analyzed using laser desorption/ionization mass spectrometry.

  13. ID-69 Sodium drain experiments

    SciTech Connect (OSTI)

    Johnston, D.C.

    1996-09-19T23:59:59.000Z

    This paper describes experiments to determine the sodium retention and drainage from the two key areas of an ID-69. This information is then used as the initiation point for guidelines of how to proceed with washing an ID-69 in the IEM Cell Sodium Removal System.

  14. Tables of thermodynamic properties of sodium

    SciTech Connect (OSTI)

    Fink, J.K.

    1982-06-01T23:59:59.000Z

    The thermodynamic properties of saturated sodium, superheated sodium, and subcooled sodium are tabulated as a function of temperature. The temperature ranges are 380 to 2508 K for saturated sodium, 500 to 2500 K for subcooled sodium, and 400 to 1600 K for superheated sodium. Tabulated thermodynamic properties are enthalpy, heat capacity, pressure, entropy, density, instantaneous thermal expansion coefficient, compressibility, and thermal pressure coefficient. Tables are given in SI units and cgs units.

  15. Titanate Anodes for Sodium Ion Batteries

    E-Print Network [OSTI]

    Doeff, Marca

    2014-01-01T23:59:59.000Z

    Company-v3832/Lithium-Ion-Batteries- Outlook-Alternative-Anodes for Sodium Ion Batteries Marca M. Doeff * , Jordirechargeable sodium ion batteries, particularly for large-

  16. Simulation of sodium boiling experiments with THERMIT sodium version

    E-Print Network [OSTI]

    Huh, Kang Yul

    1982-01-01T23:59:59.000Z

    Natural and forced convection experiments(SBTF and French) are simulated with the sodium version of the thermal-hydraulic computer code THERMIT. Simulation is done for the test secti- -on with the pressure-velocity boundary ...

  17. Hollow silica and silica-boron nano/microparticles for contrast-enhanced ultrasound to detect small tumors

    E-Print Network [OSTI]

    Kummel, Andrew C.

    Hollow silica and silica-boron nano/microparticles for contrast-enhanced ultrasound to detect small Accepted 18 March 2012 Available online 11 April 2012 Keywords: Ultrasound Nano Silica Shells Imaging detection, gas filled hollow boron-doped silica particles have been developed, which can be used

  18. Ground beef shelf life assessment as influenced by sodium lactate, sodium propionate, sodium diacetate, and soy protein concentrate 

    E-Print Network [OSTI]

    Grones, Kelly Leann

    2000-01-01T23:59:59.000Z

    In phase I all-beef and soy-added ground beef patties containing sodium lactate, sodium propionate, and sodium diacetate at various levels and combinations were stored for nine months at -10°C. Upon cooking, the addition of sodium lactate increased...

  19. CHEMISTRY OF SILICA IN CERRO PRIETO BRINES

    E-Print Network [OSTI]

    Weres, O.

    2012-01-01T23:59:59.000Z

    chemistry of silica in Cerro Prieto brine may profitably be14 mg·l-1 AND SYNTHFTIC CERRO PRIETO BRINES High Ca We112Q.by the CFE Laboratory at Cerro Prieto and kindly provided to

  20. LIGHT SCATTERING STUDIES OF SILICA AEROGELS

    E-Print Network [OSTI]

    Hunt, A.J.

    2010-01-01T23:59:59.000Z

    S.S. , "Coherent Expanded Aerogels," J. of Phys. Chern.Production of Silica Aerogel," Physica Scripta 23, Nicolaon,S.J. , "Preparation des aerogels de silice a partir

  1. Equation of state of sodium

    SciTech Connect (OSTI)

    Fritz, J.N.; Olinger, B.

    1984-03-15T23:59:59.000Z

    The volume of sodium in the bcc structure was measured at 293 K to 9 GPa using a high pressure, x-ray diffraction technique. The compression of NaF was used as the pressure gauge. These data, the shock compression data of Rice and Bakanova et al., and the melting curve data of Luedemann and Kennedy, and Ivanov et al., are all used to establish a model for the equation of state of sodium.

  2. The Management of Silica in Los Alamos National Laboratory Tap Water - A Study of Silica Solubility

    SciTech Connect (OSTI)

    Wohlberg, C.; Worland, V.P.; Kozubal, M.A.; Erickson, G.F.; Jacobson, H.M.; McCarthy, K.T.

    1999-07-01T23:59:59.000Z

    Well water at Los Alamos National Laboratory (LANL) has a silica (SiO{sub 2}) content of 60 to 100 mg/L, with 4 mg/L of magnesium, 13 mg/L calcium and lesser concentrations of other ions. On evaporation in cooling towers, when the silica concentration reaches 150 to 220 mg/L, silica deposits on heat transfer surfaces. When the high silica well water is used in the reprocessing of plutonium, silica remains in solution at the end of the process and creates a problem of removal from the effluent prior to discharge or evaporation. The work described in this Report is divided into two major parts. The first part describes the behavior of silica when the water is evaporated at various conditions of pH and in the presence of different classes of anions: inorganic and organic. In the second part of this work it was found that precipitation (floccing) of silica was a function of solution pH and mole ratio of metal to silica.

  3. E-Print Network 3.0 - alumina silica-alumina etude Sample Search...

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

    14 (2004) 681686 PII: S0960-1317(04)71691-5 Summary: for silica, alumina, and titania aerogels. Silica and alumina aerogel cantilevers are fabricated on the basis... Silica Silica...

  4. Surface-Driven Sodium Ion Energy Storage in Nanocellular Carbon...

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

    Surface-Driven Sodium Ion Energy Storage in Nanocellular Carbon Foams. Surface-Driven Sodium Ion Energy Storage in Nanocellular Carbon Foams. Abstract: Sodium ion (Na+) batteries...

  5. anticoagulant sodium citrate: Topics by E-print Network

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

    pressure-velocity boundary ... Huh, Kang Yul 1982-01-01 38 Ground beef shelf life assessment as influenced by sodium lactate, sodium propionate, sodium diacetate, and soy...

  6. Electrospinning of silica nanofibers: characterization and application to biosensing 

    E-Print Network [OSTI]

    Tsou, Pei-Hsiang

    2009-06-02T23:59:59.000Z

    and experimental time were studied. Materials used in the process are Polyvinylpyrrolidone (PVP), butanol and spin-on-glass coating solution, which act as polymer carrier, solvent, and silica-precursor, respectively. Polymer/silica precursor composite fibers were...

  7. Electrospinning of silica nanofibers: characterization and application to biosensing

    E-Print Network [OSTI]

    Tsou, Pei-Hsiang

    2009-06-02T23:59:59.000Z

    and experimental time were studied. Materials used in the process are Polyvinylpyrrolidone (PVP), butanol and spin-on-glass coating solution, which act as polymer carrier, solvent, and silica-precursor, respectively. Polymer/silica precursor composite fibers were...

  8. High resolution patterning of silica aerogels

    SciTech Connect (OSTI)

    Bertino, M.F.; Hund, J.F.; Sosa, J.; Zhang, G.; Sotiriou-Leventis, C.; Leventis, N.; Tokuhiro, A.T.; Terry, J. (UMR-MUST); (IIT)

    2008-10-30T23:59:59.000Z

    Three-dimensional metallic structures are fabricated with high spatial resolution in silica aerogels. In our method, silica hydrogels are prepared with a standard base-catalyzed route, and exchanged with an aqueous solution typically containing Ag{sup +} ions (1 M) and 2-propanol (0.2 M). The metal ions are reduced photolytically with a table-top ultraviolet lamp, or radiolytically, with a focused X-ray beam. We fabricated dots and lines as small as 30 x 70 {micro}m, protruding for several mm into the bulk of the materials. The hydrogels are eventually supercritically dried to yield aerogels, without any measurable change in the shape and spatial resolution of the lithographed structures. Transmission electron microscopy shows that illuminated regions are composed by Ag clusters with a size of several {micro}m, separated by thin layers of silica.

  9. Measurement of muonium emission from silica aerogel

    E-Print Network [OSTI]

    P. Bakule; G. A. Beer; D. Contreras; M. Esashi; Y. Fujiwara; Y. Fukao; S. Hirota; H. Iinuma; K. Ishida; M. Iwasaki; T. Kakurai; S. Kanda; H. Kawai; N. Kawamura; G. M. Marshall; H. Masuda; Y. Matsuda; T. Mibe; Y. Miyake; S. Okada; K. Olchanski; A. Olin; H. Onishi; N. Saito; K. Shimomura; P. Strasser; M. Tabata; D. Tomono; K. Ueno; K. Yokoyama; S. Yoshida

    2013-06-17T23:59:59.000Z

    Emission of muonium ($\\mu^{+}e^{-}$) atoms from silica aerogel into vacuum was observed. Characteristics of muonium emission were established from silica aerogel samples with densities in the range from 29 mg cm$^{-3}$ to 178 mg cm$^{-3}$. Spectra of muonium decay times correlated with distances from the aerogel surfaces, which are sensitive to the speed distributions, follow general features expected from a diffusion process, while small deviations from a simple room-temperature thermal diffusion model are identified. The parameters of the diffusion process are deduced from the observed yields.

  10. Measurement of muonium emission from silica aerogel

    E-Print Network [OSTI]

    Bakule, P; Contreras, D; Esashi, M; Fujiwara, Y; Fukao, Y; Hirota, S; Iinuma, H; Ishida, K; Iwasaki, M; Kakurai, T; Kanda, S; Kawai, H; Kawamura, N; Marshall, G M; Masuda, H; Matsuda, Y; Mibe, T; Miyake, Y; Okada, S; Olchanski, K; Olin, A; Onishi, H; Saito, N; Shimomura, K; Strasser, P; Tabata, M; Tomono, D; Ueno, K; Yokoyama, K; Yoshida, S

    2013-01-01T23:59:59.000Z

    Emission of muonium ($\\mu^{+}e^{-}$) atoms from silica aerogel into vacuum was observed. Characteristics of muonium emission were established from silica aerogel samples with densities in the range from 29 mg cm$^{-3}$ to 178 mg cm$^{-3}$. Spectra of muonium decay times correlated with distances from the aerogel surfaces, which are sensitive to the speed distributions, follow general features expected from a diffusion process, while small deviations from a simple room-temperature thermal diffusion model are identified. The parameters of the diffusion process are deduced from the observed yields.

  11. Lithographically directed deposition of silica nanoparticles using spin coating

    E-Print Network [OSTI]

    New Mexico, University of

    Lithographically directed deposition of silica nanoparticles using spin coating Deying Xia and S. R-assembly by spin coating to control particle placement. Three sizes of silica nanoparticles (mean diameters: 78, 50, and 15 nm) were employed for spin-coating processes. Single linear silica particle chain patterns

  12. A threshold Cherenkov detector for K separation using silica aerogel

    E-Print Network [OSTI]

    Magiera, Andrzej

    A threshold Cherenkov detector for Kþ =pþ separation using silica aerogel R. Siudak a,b , A August 2008 Keywords: Threshold Cherenkov detector Silica aerogel Reaction pp ! Kþ ðLp� Kþ =pþ separation in the focal plane of a magnetic spectrograph. Silica aerogel with refractive index of n ¼ 1:05 is applied

  13. Adsorption of Sodium Dodecyl Sulfate and Sodium Dodecyl Benzenesulfonate on Poly(Vinyl Chloride) Latexes

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Adsorption of Sodium Dodecyl Sulfate and Sodium Dodecyl Benzenesulfonate on Poly(Vinyl Chloride@cpe.fr #12;2 Abstract The adsorption of sodium dodecyl sulfate (SDS) and sodium dodecyl benzenesulfonate performed to determine the area per surfactant molecule at various temperatures (20-50ºC) and the adsorption

  14. Chemistry of Silica in Cerro Prieto Brines

    E-Print Network [OSTI]

    Weres, Oleh

    2012-01-01T23:59:59.000Z

    1975). When operated without sludge r e c i r c u l a t i ot o c o l l o i d a l silica. sludge accumulation there. thel a t i o n of part of the sludge coming out of The l a r g

  15. Chemistry of Silica in Cerro Prieto Brines

    E-Print Network [OSTI]

    Weres, O.

    2010-01-01T23:59:59.000Z

    1975). When operated without sludge r e c i r c u l a t i ot o c o l l o i d a l silica. sludge accumulation there. thel a t i o n of part of the sludge coming out of The l a r g

  16. Catalysis over activated high silica zeolites

    SciTech Connect (OSTI)

    Chang, C. D.; Miale, N.

    1985-07-23T23:59:59.000Z

    A process is provided for conducting organic compound conversion over a catalyst composition comprising a crystalline zeolite having a high initial silica-to-alumina mole ratio, said zeolite being prepared by calcining the zeolite, contacting said calcined zeolite with solid aluminum fluoride, and coverting said aluminum fluoride contacted material to hydrogen form.

  17. Molecular sieving silica membrane fabrication process

    DOE Patents [OSTI]

    Raman, N.K.; Brinker, C.J.

    1999-08-10T23:59:59.000Z

    A process is described for producing a molecular sieve silica membrane comprising depositing a hybrid organic-inorganic polymer comprising at least one organic constituent and at least one inorganic constituent on a porous substrate material and removing at least a portion of the at least one organic constituent of the hybrid organic-inorganic polymer, forming a porous film. 11 figs.

  18. Dissolution retardation of solid silica during glass batch-melting

    SciTech Connect (OSTI)

    Hrma, Pavel R.; Marcial, Jose

    2011-07-15T23:59:59.000Z

    During glass-batch melting, solid silica (quartz) usually dissolves last. A retardation function was defined as a measure of the progressive inhibition of silica dissolution that occurs during batch melting. This function is based on the comparison of the measured rate of dissolution of silica particles with the hypothetical diffusion-controlled volume flux from regularly distributed particles with uniform concentration layers around them. The severe inhibition of silica dissolution has been attributed to the irregular spatial distribution of silica particles that is associated with the formation of nearly saturated melt at a portion of their surfaces. Irregular shapes and unequal sizes of particles also contribute to their extended lifetime.

  19. Conversion of geothermal waste to commercial products including silica

    DOE Patents [OSTI]

    Premuzic, Eugene T. (East Moriches, NY); Lin, Mow S. (Rocky Point, NY)

    2003-01-01T23:59:59.000Z

    A process for the treatment of geothermal residue includes contacting the pigmented amorphous silica-containing component with a depigmenting reagent one or more times to depigment the silica and produce a mixture containing depigmented amorphous silica and depigmenting reagent containing pigment material; separating the depigmented amorphous silica and from the depigmenting reagent to yield depigmented amorphous silica. Before or after the depigmenting contacting, the geothermal residue or depigmented silica can be treated with a metal solubilizing agent to produce another mixture containing pigmented or unpigmented amorphous silica-containing component and a solubilized metal-containing component; separating these components from each other to produce an amorphous silica product substantially devoid of metals and at least partially devoid of pigment. The amorphous silica product can be neutralized and thereafter dried at a temperature from about 25.degree. C. to 300.degree. C. The morphology of the silica product can be varied through the process conditions including sequence contacting steps, pH of depigmenting reagent, neutralization and drying conditions to tailor the amorphous silica for commercial use in products including filler for paint, paper, rubber and polymers, and chromatographic material.

  20. Fire suppressing apparatus. [sodium fires

    DOE Patents [OSTI]

    Buttrey, K.E.

    1980-12-19T23:59:59.000Z

    Apparatus for smothering a liquid sodium fire comprises a pan, a perforated cover on the pan, and tubed depending from the cover and providing communication between the interior of the pan and the ambient atmosphere through the perforations in the cover. Liquid caught in the pan rises above the lower ends of the tubes and thus serves as a barrier which limits the amount of air entering the pan.

  1. Carbon nanomaterials in silica aerogel matrices

    SciTech Connect (OSTI)

    Hamilton, Christopher E [Los Alamos National Laboratory; Chavez, Manuel E [Los Alamos National Laboratory; Duque, Juan G [Los Alamos National Laboratory; Gupta, Gautam [Los Alamos National Laboratory; Doorn, Stephen K [Los Alamos National Laboratory; Dattelbaum, Andrew M [Los Alamos National Laboratory; Obrey, Kimberly A D [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    Silica aerogels are ultra low-density, high surface area materials that are extremely good thermal insulators and have numerous technical applications. However, their mechanical properties are not ideal, as they are brittle and prone to shattering. Conversely, single-walled carbon nanotubes (SWCNTs) and graphene-based materials, such as graphene oxide, have extremely high tensile strength and possess novel electronic properties. By introducing SWCNTs or graphene-based materials into aerogel matrices, it is possible to produce composites with the desirable properties of both constituents. We have successfully dispersed SWCNTs and graphene-based materials into silica gels. Subsequent supercritical drying results in monolithic low-density composites having improved mechanical properties. These nanocomposite aerogels have great potential for use in a wide range of applications.

  2. Light-scattering studies of silica aerogels

    SciTech Connect (OSTI)

    Hunt, A.J.

    1983-02-01T23:59:59.000Z

    Due to its combination of transparency and low thermal conductivity, aerogel holds considerable promise for use as insulating window materials for residential and commercial applications. This paper reports on the preliminary investigation of the optical and scattering properties of silica aerogels. It briefly describes the properties of aerogels important for window glazing applications. The optical properties are then described, followed by a discussion of the scattering measurements and their interpretation.

  3. Recent progress in silica aerogel Cherenkov radiator

    E-Print Network [OSTI]

    Makoto Tabata; Ichiro Adachi; Hideyuki Kawai; Masato Kubo; Takeshi Sato

    2012-03-19T23:59:59.000Z

    In this paper, we present recent progress in the development of hydrophobic silica aerogel as a Cherenkov radiator. In addition to the conventional method, the recently developed pin-drying method for producing high-refractive-index aerogels with high transparency was studied in detail. Optical qualities and large tile handling for crack-free aerogels were investigated. Sufficient photons were detected from high-performance aerogels in a beam test.

  4. Recent progress in silica aerogel Cherenkov radiator

    E-Print Network [OSTI]

    Tabata, Makoto; Kawai, Hideyuki; Kubo, Masato; Sato, Takeshi

    2012-01-01T23:59:59.000Z

    In this paper, we present recent progress in the development of hydrophobic silica aerogel as a Cherenkov radiator. In addition to the conventional method, the recently developed pin-drying method for producing high-refractive-index aerogels with high transparency was studied in detail. Optical qualities and large tile handling for crack-free aerogels were investigated. Sufficient photons were detected from high-performance aerogels in a beam test.

  5. Adsorption of Ruthenium and Iron Metallocenes on Silica: A Solid-State NMR Study

    E-Print Network [OSTI]

    Bluemel, Janet

    Adsorption of Ruthenium and Iron Metallocenes on Silica: A Solid- State NMR Study Kyle J. Cluff on silica surfaces by grinding the polycrystalline materials with silica. The adsorption process proceeds dry silica surface, wet and TMS- capped silica have been used as supports. The adsorption leads

  6. Silica powders for powder evacuated thermal insulating panel and method

    DOE Patents [OSTI]

    Harris, M.T.; Basaran, O.A.; Kollie, T.G.; Weaver, F.J.

    1996-01-02T23:59:59.000Z

    A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm{sup 3} and an external surface area in the range of about 90 to 600 m{sup 2}/g is described. The silica powders are prepared by reacting a tetraalkyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders. 2 figs.

  7. Silica powders for powder evacuated thermal insulating panel and method

    DOE Patents [OSTI]

    Harris, Michael T. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN); Kollie, Thomas G. (Oak Ridge, TN); Weaver, Fred J. (Knoxville, TN)

    1996-01-01T23:59:59.000Z

    A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm.sup.3 and an external surface area in the range of about 90 to 600 m.sup.2/ g is described. The silica powders are prepared by reacting a tetraakyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders.

  8. Silica powders for powder evacuated thermal insulating panel and method

    DOE Patents [OSTI]

    Harris, Michael T. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN); Kollie, Thomas G. (Oak Ridge, TN); Weaver, Fred J. (Knoxville, TN)

    1994-01-01T23:59:59.000Z

    A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm.sup.3 and an external surface area in the range of about 90 to 600 m.sup.2 /g is described. The silica powders are prepared by reacting a tetraakyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders.

  9. Silica powders for powder evacuated thermal insulating panel and method

    DOE Patents [OSTI]

    Harris, Michael T. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN); Kollie, Thomas G. (Oak Ridge, TN); Weaver, Fred J. (Knoxville, TN)

    1995-01-01T23:59:59.000Z

    A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm.sup.3 and an external surface area in the range of about 90 to 600 m.sup.2/ g is described. The silica powders are prepared by reacting a tetraakyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders.

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

    DOE Patents [OSTI]

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

    2012-09-18T23:59:59.000Z

    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.

  11. A layered sodium titanate as promising anode material for sodium ion batteries

    E-Print Network [OSTI]

    Wu, Di, S.M. Massachusetts Institute of Technology

    2014-01-01T23:59:59.000Z

    Sodium ion batteries have recently received great attention for large-scale energy applications because of the abundance and low cost of sodium source. Although some cathode materials with desirable electrochemical properties ...

  12. Sodium Titanate Anodes for Dual Intercalation Batteries

    E-Print Network [OSTI]

    Doeff, Marca M.

    2014-01-01T23:59:59.000Z

    for Dual Intercalation Batteries Lithium supply securityinterest in sodium-ion batteries. These devices operate muchsodium-ion or lithium-ion batteries that utilize them as

  13. Developing a Process for Commercial Silica Production from Geothermal Brines

    SciTech Connect (OSTI)

    Bourcier, W; Martin, S; Viani, B; Bruton, C

    2001-04-11T23:59:59.000Z

    Useful mineral by-products can be produced from geothermal brines. Although silica has many commercial uses, problems remain in producing a marketable product. We are conducting laboratory and modeling studies aimed at optimizing for rubber additive use, the properties of silica precipitates from Salton Sea and Coso-like geothermal fluids, Our goal is to develop a robust technique for producing silicas that have desirable physical and chemical properties for commercial use, while developing a generic understanding of silica precipitation that will allow extraction to be extended to additional fluid types, and to be easily modified to produce new types of marketable silica. Our experiments start with an acidified geothermal fluid similar to those treated by pH modification technology. Silica precipitation is induced by adding base and/or adding Mg or Ca salts to affect the nature of the precipitate. For the analog Salton Sea fluids, adding base alone caused silica to precipitate fairly rapidly. To date, we have characterized precipitates from experiments in which the final pH varied from 4 to 8, where NaOH and Na{sub 2}C0{sub 3} were added as bases, and CaCl{sub 2} and MgCl{sub 2} were added as salts. SEM photos of the silica precipitates from the Salton Sea and Cos0 fluids show that the silica particles are clusters of smaller silica particles down to the resolution of the SEM (about 80-100 nm in diameter). The particle sizes and surface areas of silicas from the Salton Sea and Coso analog brines are similar to the properties of the Degussa silica commonly used as a rubber additive. An evaluation of the strength of the silica-organic bond as tested by dispersion in oil (polybutadiene) was inconclusive. Neither the Degussa materials nor our laboratory precipitates dispersed readily in nor dispersed down to the fundamental particle size. Preliminary NMR data indicates that the Degussa silica has a smaller degree of silica polymerization (a slightly smaller average number of Si-0 bonds per silica tetrahedron) than the synthetic samples, but a comparable degree of hydrogen bonding of the surface silanol sites.

  14. acid functionalized silica: Topics by E-print Network

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

    between pores in SBA-15 mesostructured silicas as a function of the temperature of synthesis Mathematics Websites Summary: Functional Materials, Department of Chemistry...

  15. aperture fused silica: Topics by E-print Network

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

    fast and deep Tang, William C 6 At-wavelength characterization of UV-radiation-induced damage in fused silica Physics Websites Summary: At-wavelength characterization of...

  16. Influence of amorphous silica on the hydration in ultra-high performance concrete

    SciTech Connect (OSTI)

    Oertel, Tina, E-mail: tina.oertel@isc.fraunhofer.de [Fraunhofer–Institute for Silicate Research ISC, Neunerplatz 2, 97082 Würzburg (Germany); Inorganic Chemistry I, Universität Bayreuth, Universitätsstr. 30, 95440 Bayreuth (Germany); Helbig, Uta, E-mail: uta.helbig@th-nuernberg.de [Crystallography and X-ray Methods, Technische Hochschule Nürnberg Georg Simon Ohm, Wassertorstraße 10, 90489 Nürnberg (Germany); Hutter, Frank [Fraunhofer–Institute for Silicate Research ISC, Neunerplatz 2, 97082 Würzburg (Germany); Kletti, Holger [Building Materials, Bauhaus–Universität Weimar, Coudraystr. 11, 99423 Weimar (Germany); Sextl, Gerhard [Fraunhofer–Institute for Silicate Research ISC, Neunerplatz 2, 97082 Würzburg (Germany); Chemical Technology of Advanced Materials, Julius Maximilian Universität, Röntgenring 11, 97070 Würzburg (Germany)

    2014-04-01T23:59:59.000Z

    Amorphous silica particles (silica) are used in ultra-high performance concretes to densify the microstructure and accelerate the clinker hydration. It is still unclear whether silica predominantly increases the surface for the nucleation of C–S–H phases or dissolves and reacts pozzolanically. Furthermore, varying types of silica may have different and time dependent effects on the clinker hydration. The effects of different silica types were compared in this study by calorimetric analysis, scanning and transmission electron microscopy, in situ X-ray diffraction and compressive strength measurements. The silica component was silica fume, pyrogenic silica or silica synthesized by a wet-chemical route (Stoeber particles). Water-to-cement ratios were 0.23. Differences are observed between the silica for short reaction times (up to 3 days). Results indicate that silica fume and pyrogenic silica accelerate alite hydration by increasing the surface for nucleation of C–S–H phases whereas Stoeber particles show no accelerating effect.

  17. Fibrous composites comprising carbon nanotubes and silica

    DOE Patents [OSTI]

    Peng, Huisheng (Shanghai, CN); Zhu, Yuntian Theodore (Cary, NC); Peterson, Dean E. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM)

    2011-10-11T23:59:59.000Z

    Fibrous composite comprising a plurality of carbon nanotubes; and a silica-containing moiety having one of the structures: (SiO).sub.3Si--(CH.sub.2).sub.n--NR.sub.1R.sub.2) or (SiO).sub.3Si--(CH.sub.2).sub.n--NCO; where n is from 1 to 6, and R.sub.1 and R.sub.2 are each independently H, CH.sub.3, or C.sub.2H.sub.5.

  18. Hydrophobic silica aerogel production at KEK

    E-Print Network [OSTI]

    Tabata, Makoto; Kawai, Hideyuki; Sumiyoshi, Takayuki; Yokogawa, Hiroshi

    2011-01-01T23:59:59.000Z

    We present herein a characterization of a standard method used at the High Energy Accelerator Research Organization (KEK) to produce hydrophobic silica aerogels and expand this method to obtain a wide range of refractive index (n = 1.006-1.14). We describe in detail the entire production process and explain the methods used to measure the characteristic parameters of aerogels, namely the refractive index, transmittance, and density. We use a small-angle X-ray scattering (SAXS) technique to relate the transparency to the fine structure of aerogels.

  19. Hydrophobic silica aerogel production at KEK

    E-Print Network [OSTI]

    Makoto Tabata; Ichiro Adachi; Hideyuki Kawai; Takayuki Sumiyoshi; Hiroshi Yokogawa

    2011-12-14T23:59:59.000Z

    We present herein a characterization of a standard method used at the High Energy Accelerator Research Organization (KEK) to produce hydrophobic silica aerogels and expand this method to obtain a wide range of refractive index (n = 1.006-1.14). We describe in detail the entire production process and explain the methods used to measure the characteristic parameters of aerogels, namely the refractive index, transmittance, and density. We use a small-angle X-ray scattering (SAXS) technique to relate the transparency to the fine structure of aerogels.

  20. In-Situ Method for Treating Residual Sodium

    DOE Patents [OSTI]

    Sherman, Steven R.; Henslee, S. Paul

    2005-07-19T23:59:59.000Z

    A unique process for deactivating residual sodium in Liquid Metal Fast Breeder Reactor (LMFBR) systems which uses humidified (but not saturated) carbon dioxide at ambient temperature and pressure to convert residual sodium into solid sodium bicarbonate.

  1. ALUMINOSILICATE-COATED SILICA SAND FOR REACTIVE TRANSPORT EXPERIMENTS

    E-Print Network [OSTI]

    Flury, Markus

    ALUMINOSILICATE-COATED SILICA SAND FOR REACTIVE TRANSPORT EXPERIMENTS By JORGE ANTONIO JEREZ transport experiments; Dr. Barbara Williams and Jason Shira from University of Idaho for providing access-COATED SILICA SAND FOR REACTIVE TRANSPORT EXPERIMENTS Abstract by Jorge Antonio Jerez Briones, Ph.D. Washington

  2. Learn about the dangers of breathing silica dust

    E-Print Network [OSTI]

    Knowles, David William

    dust builds up in your lungs, you are at risk of developing a serious and irreversible lung disease silica dust. The fine particles are deposited in the lungs, causing thickening and scarring of the lung tissue. Crystalline silica exposure has also been linked to lung cancer. A worker may develop any

  3. Community Geothermal Technology Program: Silica bronze project. Final report

    SciTech Connect (OSTI)

    Bianchini, H.

    1989-10-01T23:59:59.000Z

    Objective was to incorporate waste silica from the HGP-A geothermal well in Pohoiki with other refractory materials for investment casting of bronze sculpture. The best composition for casting is about 50% silica, 25% red cinders, and 25% brick dust; remaining ingredient is a binder, such as plaster and water.

  4. High-capacity hydrogen storage in lithium and sodium amidoboranes...

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

    capacity hydrogen storage in lithium and sodium amidoboranes. High-capacity hydrogen storage in lithium and sodium amidoboranes. Abstract: A substantial effort worldwide has been...

  5. SciTech Connect: Thermodynamic and transport properties of sodium...

    Office of Scientific and Technical Information (OSTI)

    of state calculations on thermophysical properties of sodium have been included in this critical assessment. Thermodynamic properties of sodium liquid and vapor that have been...

  6. A resting bottom sodium cooled fast reactor

    SciTech Connect (OSTI)

    Costes, D. [Consultant (France)

    2012-07-01T23:59:59.000Z

    This follows ICAPP 2011 paper 11059 'Fast Reactor with a Cold Bottom Vessel', on sodium cooled reactor vessels in thermal gradient, resting on soil. Sodium is frozen on vessel bottom plate, temperature increasing to the top. The vault cover rests on the safety vessel, the core diagrid welded to a toric collector forms a slab, supported by skirts resting on the bottom plate. Intermediate exchangers and pumps, fixed on the cover, plunge on the collector. At the vessel top, a skirt hanging from the cover plunges into sodium, leaving a thin circular slit partially filled by sodium covered by argon, providing leak-tightness and allowing vessel dilatation, as well as a radial relative holding due to sodium inertia. No 'air conditioning' at 400 deg. C is needed as for hanging vessels, and this allows a large economy. The sodium volume below the slab contains isolating refractory elements, stopping a hypothetical corium flow. The small gas volume around the vessel limits any LOCA. The liner cooling system of the concrete safety vessel may contribute to reactor cooling. The cold resting bottom vessel, proposed by the author for many years, could avoid the complete visual inspection required for hanging vessels. However, a double vessel, containing support skirts, would allow introduction of inspecting devices. Stress limiting thermal gradient is obtained by filling secondary sodium in the intermediate space. (authors)

  7. Luminescent organosilicon polymers and sol-gel synthesis of nano-structured silica

    E-Print Network [OSTI]

    Martinez, H. Paul

    2011-01-01T23:59:59.000Z

    filled   hollow   silica   nano-­?   and   microshells  nano-­? extracting  sensor.   Conclusions   The   adsorptive   properties   of   hollow  

  8. Kinetics of wet sodium vapor complex plasma

    SciTech Connect (OSTI)

    Mishra, S. K., E-mail: nishfeb@rediffmail.com [Institute for Plasma Research (IPR), Gandhinagar 382428 (India); Sodha, M. S. [Centre of Energy Studies, Indian Institute of Technology Delhi (IITD), New Delhi 110016 (India)] [Centre of Energy Studies, Indian Institute of Technology Delhi (IITD), New Delhi 110016 (India)

    2014-04-15T23:59:59.000Z

    In this paper, we have investigated the kinetics of wet (partially condensed) Sodium vapor, which comprises of electrons, ions, neutral atoms, and Sodium droplets (i) in thermal equilibrium and (ii) when irradiated by light. The formulation includes the balance of charge over the droplets, number balance of the plasma constituents, and energy balance of the electrons. In order to evaluate the droplet charge, a phenomenon for de-charging of the droplets, viz., evaporation of positive Sodium ions from the surface has been considered in addition to electron emission and electron/ion accretion. The analysis has been utilized to evaluate the steady state parameters of such complex plasmas (i) in thermal equilibrium and (ii) when irradiated; the results have been graphically illustrated. As a significant outcome irradiated, Sodium droplets are seen to acquire large positive potential, with consequent enhancement in the electron density.

  9. Radial power flattening in sodium fast reactors

    E-Print Network [OSTI]

    Krentz-Wee, Rebecca (Rebecca Elizabeth)

    2012-01-01T23:59:59.000Z

    In order to improve a new design for a uranium startup sodium cooled fast reactor which was proposed at MIT, this thesis evaluated radial power flattening by varying the fuel volume fraction at a fixed U-235 enrichment of ...

  10. Low-Pressure Sodium Lighting Basics

    Broader source: Energy.gov [DOE]

    Low-pressure sodium lighting provides more energy-efficient outdoor lighting than high-intensity discharge lighting, but it has very poor color rendition. Typical applications include highway and security lighting, where color is not important.

  11. Ambient-pressure silica aerogel films

    SciTech Connect (OSTI)

    Prakash, S.S. [New Mexico Univ., Albuquerque, NM (United States); Brinker, C.J. [New Mexico Univ., Albuquerque, NM (United States)]|[Sandia National Labs., Albuquerque, NM (United States); Hurd, A.J. [Sandia National Labs., Albuquerque, NM (United States)

    1994-12-31T23:59:59.000Z

    Very highly porous (aerogel) silica films with refractive index in the range 1.006--1.05 (equivalent porosity 98.5--88%) were prepared by an ambient-pressure process. It was shown earlier using in situ ellipsometric imaging that the high porosity of these films was mainly attributable to the dilation or `springback` of the film during the final stage of drying. This finding was irrefutably reconfirmed by visually observing a `springback` of >500% using environmental scanning electron microscopy (ESEM). Ellipsometry and ESEM also established the near cent per cent reversibility of aerogel film deformation during solvent intake and drying. Film thickness profile measurements (near the drying line) for the aerogel, xerogel and pure solvent cases are presented from imaging ellipsometry. The thickness of these films (crack-free) were controlled in the range 0.1-3.5 {mu}m independent of refractive index.

  12. Development of Silica Aerogel with Any Density

    E-Print Network [OSTI]

    M. Tabata; I. Adachi; T. Fukushima; H. Kawai; H. Kishimoto; A. Kuratani; H. Nakayama; S. Nishida; T. Noguchi; K. Okudaira; Y. Tajima; H. Yano; H. Yokogawa; H. Yoshida

    Abstract–New production methods of silica aerogel with high and low refractive indices have been developed. A very slow shrinkage of alcogel at room temperature has made possible producing aerogel with high refractive indices of up to 1.265 without cracks. Even higher refractive indices than 1.08, the transmission length of the aerogel obtained from this technique has been measured to be about 10 to 20 mm at 400 nm wave length. A mold made of alcogel which endures shrinkage in the supercritical drying process has provided aerogel with the extremely low density of 0.009g/cm 3, which corresponds to the refractive index of 1.002. We have succeeded producing aerogel with a wide range of densities. I.

  13. Quantification of residual stress from photonic signatures of fused silica

    SciTech Connect (OSTI)

    Cramer, K. Elliott; Yost, William T. [NASA Langley Research Center, Hampton, VA 23681 (United States); Hayward, Maurice [College of William and Mary, Williamsburg, VA 23185 (United States)

    2014-02-18T23:59:59.000Z

    A commercially available grey-field polariscope (GFP) instrument for photoelastic examination is used to assess impact damage inflicted upon the outer-most pane of Space Shuttle windows made from fused silica. A method and apparatus for calibration of the stress-optic coefficient using four-point bending is discussed. The results are validated on known material (acrylic) and are found to agree with literature values to within 6%. The calibration procedure is then applied to fused-silica specimens and the stress-optic coefficient is determined to be 2.43 ± 0.54 × 10{sup ?12} Pa{sup ?1}. Fused silica specimens containing impacts artificially made at NASA’s Hypervelocity Impact Technology Facility (HIT-F), to simulate damage typical during space flight, are examined. The damage sites are cored from fused silica window carcasses and examined with the GFP. The calibrated GFP measurements of residual stress patterns surrounding the damage sites are presented.

  14. aminopropyl silica gel: Topics by E-print Network

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

    Summary: We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying...

  15. amorphous silica systems: Topics by E-print Network

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

    progress in the development and mass production of large-area hydrophobic silica aerogels for use as radiators in the aerogel-based ring-imaging Cherenkov (A-RICH) counter,...

  16. acid modified silica: Topics by E-print Network

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

    J. Cryan; John G. Rarity; Siyuan Yu; Jeremy L. O'Brien 2008-02-01 83 Hydrophobic silica aerogel production at KEK Nuclear Experiment (arXiv) Summary: We present herein a...

  17. Mesoporous-silica films, fibers, and powders by evaporation ...

    Office of Scientific and Technical Information (OSTI)

    fiber formation starts with a similar silica precursor solution but with an added pre-polymer making a pituitous mixture that is drawn into a thin strand from which solvent is...

  18. Bioresponsive Mesoporous Silica Nanoparticles for Triggered Drug Release

    E-Print Network [OSTI]

    Singh, Neetu

    Mesoporous silica nanoparticles (MSNPs) have garnered a great deal of attention as potential carriers for therapeutic payloads. However, achieving triggered drug release from MSNPs in vivo has been challenging. Here, we ...

  19. Experimental evaluation of heat transfer characteristics of silica nanofluid

    E-Print Network [OSTI]

    Zhang, Zihao, S.B. Massachusetts Institute of Technology

    2010-01-01T23:59:59.000Z

    The laminar convective heat transfer characteristics were investigated for silica nanofluid. An experimental loop was built to obtain heat transfer coefficients for single-phase nanofluids in a circular conduit in laminar ...

  20. Method and system for producing hydrogen using sodium ion separation membranes

    DOE Patents [OSTI]

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

    2013-05-21T23:59:59.000Z

    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.

  1. Mesoporous-silica films, fibers, and powders by evaporation

    DOE Patents [OSTI]

    Bruinsma, P.J.; Baskaran, S.; Bontha, J.R.; Liu, J.

    1999-07-13T23:59:59.000Z

    This invention pertains to surfactant-templated nanometer-scale porosity of a silica precursor solution and forming a mesoporous material by first forming the silica precursor solution into a preform having a high surface area to volume ratio, then rapid drying or evaporating a solvent from the silica precursor solution. The mesoporous material may be in any geometric form, but is preferably in the form of a film, fiber, powder or combinations thereof. The rapid drying or evaporation of solvent from the solution is accomplished by layer thinning, for example spin casting, liquid drawing, and liquid spraying respectively. Production of a film is by layer thinning, wherein a layer of the silica precursor solution is formed on a surface followed by removal of an amount of the silica precursor solution and leaving a geometrically thinner layer of the silica precursor solution from which the solvent quickly escapes via evaporation. Layer thinning may be by any method including but not limited to squeegeeing and/or spin casting. In powder formation by spray drying, the same conditions of fast drying exists as in spin-casting (as well as in fiber spinning) because of the high surface-area to volume ratio of the product. When a powder is produced by liquid spraying, the particles or micro-bubbles within the powder are hollow spheres with walls composed of mesoporous silica. Mesoporous fiber formation starts with a similar silica precursor solution but with an added pre-polymer making a pituitous mixture that is drawn into a thin strand from which solvent is evaporated leaving the mesoporous fiber(s). 24 figs.

  2. Effects of sodium lactate and sodium propionate on the sensory, microbial, and chemical characteristics of fresh aerobically stored ground beef

    E-Print Network [OSTI]

    Eckert, Laura Anne

    1995-01-01T23:59:59.000Z

    Coarse ground beef was mixed with sodium lactate (0, 3, or 4%) alone or in combination with sodium propionate (0. 1 or 0. 2%). The mixtures were then re-ground and formed into hamburger patties, which were placed in Styrofoam meat trays and overwrapped... sodium lactate tended to be sweeter than control patties. Hamburger patties with sodium lactate were springier. more cohesive. and less crumbly than the control patties. Treatments containing 0. 2% sodium propionate were more juicy than the control...

  3. Silica Extraction at the Mammoth Lakes Geothermal Site

    SciTech Connect (OSTI)

    Bourcier, W; Ralph, W; Johnson, M; Bruton, C; Gutierrez, P

    2006-06-07T23:59:59.000Z

    The purpose of this project is to develop a cost-effective method to extract marketable silica (SiO{sub 2}) from fluids at the Mammoth Lakes, California geothermal power plant. Marketable silica provides an additional revenue source for the geothermal power industry and therefore lowers the costs of geothermal power production. The use of this type of ''solution mining'' to extract resources from geothermal fluids eliminates the need for acquiring these resources through energy intensive and environmentally damaging mining technologies. We have demonstrated that both precipitated and colloidal silica can be produced from the geothermal fluids at Mammoth Lakes by first concentrating the silica to over 600 ppm using reverse osmosis (RO). The RO permeate can be used in evaporative cooling at the plant; the RO concentrate is used for silica and potentially other (Li, Cs, Rb) resource extraction. Preliminary results suggest that silica recovery at Mammoth Lakes could reduce the cost of geothermal electricity production by 1.0 cents/kWh.

  4. Further Investigations of the Effect of Replacing Lithium by Sodium on Lithium Silicate Scintillating Glass Efficiency

    SciTech Connect (OSTI)

    Bliss, Mary; Aker, Pamela M.; Windisch, Charles F.

    2012-02-15T23:59:59.000Z

    Ce3+ doped lithium (6Li) silicate glasses are thermal neutron detectors. Prior work showed that when sodium (Na) is substituted for Li the scintillation efficiency, under beta particle stimulation, increased and then decreased as the sodium (Na) content was increased [1]. When all the 6Li was replaced by Na no scintillation was observed. Raman spectra, acquired using a visible excitation source provided no evidence of anomalous behavior. SEM microscopy did show some phase separation, but there was no obvious correlation with the scintillation efficiency. We have reexamined these glass samples using deep UV Raman excitation which reduces fluorescence interference. The newly acquired spectra show evidence of phase separation in the glasses. Specifically we see a peak at 800 cm-1 Raman shift which can be assigned to a vitreous silica moiety that results from phase separation. There is a strong correlation between this peak's area, the scintillation efficiency, and the Na content. The observed trend suggests that phase separation enhances scintillation and addition of Na reduces the amount of phase separation. We also see evidence of at least two defect structures that can be tentatively assigned to a three-membered ring structure and an oxygen vacancy. The latter is fairly strongly correlated with enhanced scintillation efficiency.

  5. Method of making a sodium sulfur battery

    DOE Patents [OSTI]

    Elkins, P. E.

    1981-09-22T23:59:59.000Z

    A method of making a portion of a sodium sulfur battery is disclosed. The battery portion made is a portion of the container which defines the volume for the cathodic reactant materials which are sulfur and sodium polysulfide materials. The container portion is defined by an outer metal casing with a graphite liner contained therein, the graphite liner having a coating on its internal diameter for sealing off the porosity thereof. The steel outer container and graphite pipe are united by a method which insures that at the operating temperature of the battery, relatively low electrical resistance exists between the two materials because they are in intimate contact with one another. 3 figs.

  6. Sodium-tetravalent sulfur molten chloroaluminate cell

    DOE Patents [OSTI]

    Mamantov, Gleb (Knoxville, TN)

    1985-04-02T23:59:59.000Z

    A sodium-tetravalent sulfur molten chloroaluminate cell with a .beta."-alumina sodium ion conductor having a S-Al mole ratio of above about 0.15 in an acidic molten chloroaluminate cathode composition is disclosed. The cathode composition has an AlCl.sub.3 -NaCl mole percent ratio of above about 70-30 at theoretical full charge. The cell provides high energy densities at low temperatures and provides high energy densities and high power densities at moderate temperatures.

  7. Sodium hypochlorite Market | OpenEI Community

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit with form HistoryRistmaSinosteel CorporationSocovoltaic Systems JumpSodiumSodium

  8. Silica recovery and control in Hawaiian geothermal fluids

    SciTech Connect (OSTI)

    Thomas, D.M.

    1992-06-01T23:59:59.000Z

    A series of experiments was performed to investigate methods of controlling silica in waste geothermal brines produced at the HGP-A Generator Facility. Laboratory testing has shown that the rate of polymerization of silica in the geothermal fluids is highly pH dependent. At brine pH values in excess of 8.5 the suspension of silica polymers flocculated and rapidly precipitated a gelatinous silica mass. Optimum flocculation and precipitation rates were achieved at pH values in the range of 10.5 to 11.5. The addition of transition metal salts to the geothermal fluids similarly increased the rate of polymerization as well as the degree of precipitation of the silica polymer from suspension. A series of experiments performed on the recovered silica solids demonstrated that methanol extraction of the water in the gels followed by critical point drying yielded surface areas in excess of 300 M{sup 2}/g and that treatment of the dried solids with 2 N HCl removed most of the adsorbed impurities in the recovered product. A series of experiments tested the response of the waste brines to mixing with steam condensate and non-condensable gases.The results demonstrated that the addition of condensate and NCG greatly increased the stability of the silica in the geothermal brines. They also indicated that the process could reduce the potential for plugging of reinjection wells receiving waste geothermal fluids from commercial geothermal facilities in Hawaii. Conceptual designs were proposed to apply the gas re-combination approach to the disposal of geothermal waste fluids having a range of chemical compositions. Finally, these designs were applied to the geothermal fluid compositions found at Cerro Prieto, Ahuachapan, and Salton Sea.

  9. Silica recovery and control in Hawaiian geothermal fluids. Final report

    SciTech Connect (OSTI)

    Thomas, D.M.

    1992-06-01T23:59:59.000Z

    A series of experiments was performed to investigate methods of controlling silica in waste geothermal brines produced at the HGP-A Generator Facility. Laboratory testing has shown that the rate of polymerization of silica in the geothermal fluids is highly pH dependent. At brine pH values in excess of 8.5 the suspension of silica polymers flocculated and rapidly precipitated a gelatinous silica mass. Optimum flocculation and precipitation rates were achieved at pH values in the range of 10.5 to 11.5. The addition of transition metal salts to the geothermal fluids similarly increased the rate of polymerization as well as the degree of precipitation of the silica polymer from suspension. A series of experiments performed on the recovered silica solids demonstrated that methanol extraction of the water in the gels followed by critical point drying yielded surface areas in excess of 300 M{sup 2}/g and that treatment of the dried solids with 2 N HCl removed most of the adsorbed impurities in the recovered product. A series of experiments tested the response of the waste brines to mixing with steam condensate and non-condensable gases.The results demonstrated that the addition of condensate and NCG greatly increased the stability of the silica in the geothermal brines. They also indicated that the process could reduce the potential for plugging of reinjection wells receiving waste geothermal fluids from commercial geothermal facilities in Hawaii. Conceptual designs were proposed to apply the gas re-combination approach to the disposal of geothermal waste fluids having a range of chemical compositions. Finally, these designs were applied to the geothermal fluid compositions found at Cerro Prieto, Ahuachapan, and Salton Sea.

  10. Functionalized mesoporous silica nanoparticles for oral delivery of budesonide

    SciTech Connect (OSTI)

    Yoncheva, K., E-mail: krassi.yoncheva@gmail.com [Department of Pharmaceutical Technology, Faculty of Pharmacy, Medical University of Sofia, 2 Dunav Str., 1000 Sofia (Bulgaria); Popova, M. [Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia (Bulgaria); Szegedi, A.; Mihaly, J. [Institute of Nanochemistry and Catalysis, Chemical Research Center, Hungarian Academy of Sciences, Pusztaszeri út. 59-67, 1025 Budapest (Hungary); Tzankov, B.; Lambov, N.; Konstantinov, S.; Tzankova, V. [Department of Pharmaceutical Technology, Faculty of Pharmacy, Medical University of Sofia, 2 Dunav Str., 1000 Sofia (Bulgaria); Pessina, F.; Valoti, M. [Dipartimento di Scienze della Vita, Universita di Siena, via Aldo Moro 2, Siena (Italy)

    2014-03-15T23:59:59.000Z

    Non-functionalized and amino-functionalized mesoporous silica nanoparticle were loaded with anti-inflammatory drug budesonide and additionally post-coated with bioadhesive polymer (carbopol). TEM images showed spherical shape of the nanoparticles and slightly higher polydispersity after coating with carbopol. Nitrogen physisorption and thermogravimetic analysis revealed that more efficient loading and incorporation into the pores of nanoparticles was achieved with the amino-functionalized silica carrier. Infrared spectra indicated that the post-coating of these nanoparticles with carbopol led to the formation of bond between amino groups of the functionalized carrier and carboxyl groups of carbopol. The combination of amino-functionalization of the carrier with the post-coating of the nanoparticles sustained budesonide release. Further, an in vitro model of inflammatory bowel disease showed that the cytoprotective effect of budesonide loaded in the post-coated silica nanoparticles on damaged HT-29 cells was more pronounced compared to the cytoprotection obtained with pure budesonide. -- Graphical abstract: Silica mesoporous MCM-41 particles were amino-functionalized, loaded with budesonide and post-coated with bioadhesive polymer (carbopol) in order to achieve prolonged residence of anti-inflammatory drug in GIT. Highlights: • Higher drug loading in amino-functionalized mesoporous silica. • Amino-functionalization and post-coating of the nanoparticles sustained drug release. • Achievement of higher cytoprotective effect with drug loaded into the nanoparticles.

  11. Temperature and moisture dependence of dielectric constant for silica aerogels

    SciTech Connect (OSTI)

    Hrubesh, L.H., LLNL

    1997-03-01T23:59:59.000Z

    The dielectric constants of silica aerogels are among the lowest measured for any solid material. The silica aerogels also exhibit low thermal expansion and are thermally stable to temperatures exceeding 500{degrees}C. However, due to the open porosity and large surface areas for aerogels, their dielectric constants are strongly affected by moisture and temperature. This paper presents data for the dielectric constants of silica aerogels as a function of moisture content at 25{degrees}C, and as a function of temperature, for temperatures in the range from 25{degrees}C to 450{degrees}C. Dielectric constant data are also given for silica aerogels that are heat treated in dry nitrogen at 500{degrees}C, then cooled to 25{degrees}C for measurements in dry air. All measurements are made on bulk aerogel spheres at 22GHz microwave frequency, using a cavity perturbation method. The results of the dependence found here for bulk materials can be inferred to apply also to thin films of silica aerogels having similar nano-structures and densities.

  12. Experimental Simulation of Evaporation-Driven Silica Sinter Formation and Microbial Silicification in Hot Spring Systems

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    in geothermal waters after they have reached the surface. Water evaporation is, along with cooling, one Evaporation of silica-rich geothermal waters is one of the main abiotic drivers of the formation of silica

  13. Surface modification of low density silica and bridged polysilsesquioxane aerogels

    SciTech Connect (OSTI)

    DeFriend, K. A. (Kimberly A.); Loy, D. A. (Douglas A.); Salazar, K. V. (Kenneth V.); Wilson, K. V. (Kennard V.)

    2004-01-01T23:59:59.000Z

    Silica and bridged polysilsesquioxane aerogels are low density materials that are attractive for applications such as, thermal insulation, porous separation media or catalyst supports, adsorbents. However, aerogels are notoriously weak and brittle making it difficult to handle and machine monoliths into desired forms. This prevents the development of many applications that would otherwise benefit from the use of the low density materials. We will describe our efforts to chemically modify and mechanically enhance silica-based aerogels using chemical vapor techniques without sacrificing their characteristic low densities. Monolithic silica and organically bridged polysilsesquioxane aerogels were prepared by sol-gel polymerization of the respective methoxysilane monomers followed by supercritical carbon dioxide drying of the gels. Reactive modification of the gels with volatile silylating compounds during and after the drying process and these effects on the mechanical properties and density of the aerogels will be described.

  14. PATCHY SILICA-COATED SILVER NANOWIRES AS SERS SUBSTRATES

    SciTech Connect (OSTI)

    Murph, S.; Murphy, C.

    2013-03-29T23:59:59.000Z

    We report a class of core-shell nanomaterials that can be used as efficient surface-enhancement Raman scattering (SERS) substrates. The core consists of silver nanowires, prepared through a chemical reduction process, that are used to capture 4- mercaptobenzoic acid (4-MBA), a model analyte. The shell was prepared through a modified Stöber method and consists of patchy or full silica coats. The formation of silica coats was monitored via transmission electron microscopy, UV-visible spectroscopy and phase-analysis light scattering for measuring effective surface charge. Surprisingly, the patchy silica coated silver nanowires are better SERS substrate than silver nanowires; nanomolar concentration of 4-MBA can be detected. In addition, “nano-matryoshka” configurations were used to quantitate/explore the effect of the electromagnetic field at the tips of the nanowire (“hot spots”) in the Raman scattering experiment.

  15. Sodium and sulfur release and recapture during black liquor burning

    SciTech Connect (OSTI)

    Frederick, W.J.; Iisa, K.; Wag, K.; Reis, V.V.; Boonsongsup, L.; Forssen, M.; Hupa, M.

    1995-08-01T23:59:59.000Z

    The objective of this study was to provide data on sulfur and sodium volatilization during black liquor burning, and on SO2 capture by solid sodium carbonate and sodium chloride. This data was interpreted and modeled into rate equations suitable for use in computational models for recovery boilers.

  16. Corrosion performance of advanced structural materials in sodium.

    SciTech Connect (OSTI)

    Natesan, K.; Momozaki, Y.; Li, M.; Rink, D.L. (Nuclear Engineering Division)

    2012-05-16T23:59:59.000Z

    This report gives a description of the activities in design, fabrication, construction, and assembling of a pumped sodium loop for the sodium compatibility studies on advanced structural materials. The work is the Argonne National Laboratory (ANL) portion of the effort on the work project entitled, 'Sodium Compatibility of Advanced Fast Reactor Materials,' and is a part of Advanced Materials Development within the Reactor Campaign. The objective of this project is to develop information on sodium corrosion compatibility of advanced materials being considered for sodium reactor applications. This report gives the status of the sodium pumped loop at Argonne National Laboratory, the specimen details, and the technical approach to evaluate the sodium compatibility of advanced structural alloys. This report is a deliverable from ANL in FY2010 (M2GAN10SF050302) under the work package G-AN10SF0503 'Sodium Compatibility of Advanced Fast Reactor Materials.' Two reports were issued in 2009 (Natesan and Meimei Li 2009, Natesan et al. 2009) which examined the thermodynamic and kinetic factors involved in the purity of liquid sodium coolant for sodium reactor applications as well as the design specifications for the ANL pumped loop for testing advanced structural materials. Available information was presented on solubility of several metallic and nonmetallic elements along with a discussion of the possible mechanisms for the accumulation of impurities in sodium. That report concluded that the solubility of many metals in sodium is low (<1 part per million) in the temperature range of interest in sodium reactors and such trace amounts would not impact the mechanical integrity of structural materials and components. The earlier report also analyzed the solubility and transport mechanisms of nonmetallic elements such as oxygen, nitrogen, carbon, and hydrogen in laboratory sodium loops and in reactor systems such as Experimental Breeder Reactor-II, Fast Flux Test Facility, and Clinch River Breeder Reactor. Among the nonmetallic elements discussed, oxygen is deemed controllable and its concentration in sodium can be maintained in sodium for long reactor life by using cold-trap method. It was concluded that among the cold-trap and getter-trap methods, the use of cold trap is sufficient to achieve oxygen concentration of the order of 1 part per million. Under these oxygen conditions in sodium, the corrosion performance of structural materials such as austenitic stainless steels and ferritic steels will be acceptable at a maximum core outlet sodium temperature of {approx}550 C. In the current sodium compatibility studies, the oxygen concentration in sodium will be controlled and maintained at {approx}1 ppm by controlling the cold trap temperature. The oxygen concentration in sodium in the forced convection sodium loop will be controlled and monitored by maintaining the cold trap temperature in the range of 120-150 C, which would result in oxygen concentration in the range of 1-2 ppm. Uniaxial tensile specimens are being exposed to flowing sodium and will be retrieved and analyzed for corrosion and post-exposure tensile properties. Advanced materials for sodium exposure include austenitic alloy HT-UPS and ferritic-martensitic steels modified 9Cr-1Mo and NF616. Among the nonmetallic elements in sodium, carbon was assessed to have the most influence on structural materials since carbon, as an impurity, is not amenable to control and maintenance by any of the simple purification methods. The dynamic equilibrium value for carbon in sodium systems is dependent on several factors, details of which were discussed in the earlier report. The current sodium compatibility studies will examine the role of carbon concentration in sodium on the carburization-decarburization of advanced structural materials at temperatures up to 650 C. Carbon will be added to the sodium by exposure of carbon-filled iron tubes, which over time will enable carbon to diffuse through iron and dissolve into sodium. The method enables addition of dissolved carbon (without carb

  17. Effects of sodium lactate and sodium propionate on the sensory, microbial, and chemical characteristics of fresh aerobically stored ground beef 

    E-Print Network [OSTI]

    Eckert, Laura Anne

    1995-01-01T23:59:59.000Z

    EFFECTS OF SODIUM LACTATE AND SODIUM PROPIONATE ON THE SENSORY, MICROBIAL, AND CHEMICAL CHARACTERISTICS OF FRESH AEROBICALLY STORED GROUND BEEF A Thesis by LAURA ANNE ECKERT 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 December 1995 Major Subject: Food Science and Technology EFFECTS OF SODIUM LACTATE AND SODIUM PROPIONATE ON THE SENSORY, MICROBIAL, AND CHEMICAL CHARACTERISTICS OF FRESH...

  18. Hierarchical Silica Nanostructures Inspired by Diatom Algae Yield Superior Deformability, Toughness, and Strength

    E-Print Network [OSTI]

    Buehler, Markus J.

    Hierarchical Silica Nanostructures Inspired by Diatom Algae Yield Superior Deformability, Toughness algae that is mainly composed of amorphous silica, which features a hierarchical structure that ranges in diatom algae as a basis to study a bioinspired nanoporous material implemented in crystalline silica. We

  19. Analysis of the elastic behaviour of silica aerogels taken as a percolating system

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    289 Analysis of the elastic behaviour of silica aerogels taken as a percolating system T. Woignier of silica aerogels are performed using the three points flexural technique. The elastic behaviour is studied measurement - for silica aerogels. These highly porous materials are obtained from a sol-gel process. Solvent

  20. Multicomponent Transport of Sulfate in a Goethite-Silica Sand System

    E-Print Network [OSTI]

    Sparks, Donald L.

    Multicomponent Transport of Sulfate in a Goethite-Silica Sand System at Variable pH and Ionic of protons and sulfate on goethite and silica were used in combination with a one-dimensional mass-transport model to predict the transport of sulfate at variable pH and ionic strength in a goethite-silica system

  1. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect (OSTI)

    Fox, K. M.; Roberts, K. A.; Edwards, T. B.

    2014-02-28T23:59:59.000Z

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leachability indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste form. The thermal analyses completed in this study provide some preliminary insight, although the l

  2. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect (OSTI)

    Fox, K. M.; Roberts, K. A.; Edwards, T. B.

    2013-09-17T23:59:59.000Z

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leach indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste form. The thermal analyses completed in this study provide some preliminary insight, although the limited

  3. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect (OSTI)

    Fox, K. M.; Edwards, T. A.; Roberts, K. B.

    2013-10-02T23:59:59.000Z

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leach indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste form. The thermal analyses completed in this study provide some preliminary insight, although the limited

  4. Development of Silica/Vanadia/ Titania Catalysts for Removal of

    E-Print Network [OSTI]

    Li, Ying

    mercury (Hg0) from simulated coal-combustion flue gas. Experiments were carried out in fixed-bed reactorsDevelopment of Silica/Vanadia/ Titania Catalysts for Removal of Elemental Mercury from Coal-Combustion the composition and microstructures of SCR (selective catalytic reduction) catalysts for Hg0 oxidation in coal-combustion

  5. Silica dust control when drilling concrete Page 1 of 2

    E-Print Network [OSTI]

    Knowles, David William

    Silica dust control when drilling concrete Page 1 of 2 Drilling into concrete releases a fine sandy and routinely drill into concrete are at risk of developing this disease. Controlling the dust Hammer drills are available with attached dust removal systems. These draw dust from the drill end, down the attachment

  6. Fractal Studies on Titanium-Silica Aerogels using SMARTer

    SciTech Connect (OSTI)

    Putra, E. Giri Rachman; Ikram, A.; Bharoto; Santoso, E. [Neutron Scattering Laboratory, BATAN, Kawasan Puspiptek Serpong, Tangerang 15314 (Indonesia); Fang, T. Chiar; Ibrahim, N. [Department of Physics, Faculty of Science Universiti Teknologi Malaysia (UTM), 81310 Skudai, Johor (Malaysia); Mohamed, A. Aziz [Materials Technology Group, Industrial Technology Division Agensi Nuklear Malaysia, 43000 Kajang (Malaysia)

    2008-03-17T23:59:59.000Z

    Power-law scattering approximation has been employed to reveal the fractal structures of solid-state titanium-silica aerogel samples. All small-angle neutron scattering (SANS) measurements were performed using 36 meters SANS BATAN spectrometer (SMARTer) at the neutron scattering laboratory (NSL) in Serpong, Indonesia. The mass fractal dimension of titanium-silica aerogels at low scattering vector q range increases from -1.4 to -1.92 with the decrease of acid concentrations during sol-gel process. These results are attributed to the titanium-silica aerogels that are growing to more polymeric and branched structures. At high scattering vector q range the Porod slope of -3.9 significantly down to -2.24 as the roughness of particle surfaces becomes higher. The cross over between these two regimes decreases from 0.4 to 0.16 nm{sup -1} with the increase of acid concentrations indicating also that the titanium-silica aerogels are growing.

  7. Flue gas injection control of silica in cooling towers.

    SciTech Connect (OSTI)

    Brady, Patrick Vane; Anderson, Howard L., Jr.; Altman, Susan Jeanne

    2011-06-01T23:59:59.000Z

    Injection of CO{sub 2}-laden flue gas can decrease the potential for silica and calcite scale formation in cooling tower blowdown by lowering solution pH to decrease equilibrium calcite solubility and kinetic rates of silica polymerization. Flue gas injection might best inhibit scale formation in power plant cooling towers that use impaired makeup waters - for example, groundwaters that contain relatively high levels of calcium, alkalinity, and silica. Groundwaters brought to the surface for cooling will degas CO{sub 2} and increase their pH by 1-2 units, possibly precipitating calcite in the process. Recarbonation with flue gas can lower the pHs of these fluids back to roughly their initial pH. Flue gas carbonation probably cannot lower pHs to much below pH 6 because the pHs of impaired waters, once outgassed at the surface, are likely to be relatively alkaline. Silica polymerization to form scale occurs most rapidly at pH {approx} 8.3 at 25 C; polymerization is slower at higher and lower pH. pH 7 fluids containing {approx}220 ppm SiO{sub 2} require > 180 hours equilibration to begin forming scale whereas at pH 8.3 scale formation is complete within 36 hours. Flue gas injection that lowers pHs to {approx} 7 should allow substantially higher concentration factors. Periodic cycling to lower recoveries - hence lower silica concentrations - might be required though. Higher concentration factors enabled by flue gas injection should decrease concentrate volumes and disposal costs by roughly half.

  8. Journal of Magnetism and Magnetic Materials 303 (2006) 163166 One-dimensional assemblies of silica-coated cobalt nanoparticles

    E-Print Network [OSTI]

    Entel, P.

    2006-01-01T23:59:59.000Z

    in revised form 28 October 2005 Available online 28 November 2005 Abstract Silica-coated cobalt nanoparticles for the formation process. Kobayashi et al. [3h] reported the synthesis of silica- coated cobalt nanoparticles which-defined silica shells. Varying the process led us to produce silica-coated chains of 32 nm cobalt nanoparticles

  9. Report on sodium compatibility of advanced structural materials.

    SciTech Connect (OSTI)

    Li, M.; Natesan, K.; Momozaki, Y.; Rink, D.L.; Soppet, W.K.; Listwan, J.T. (Nuclear Engineering Division)

    2012-07-09T23:59:59.000Z

    This report provides an update on the evaluation of sodium compatibility of advanced structural materials. The report is a deliverable (level 3) in FY11 (M3A11AN04030403), under the Work Package A-11AN040304, 'Sodium Compatibility of Advanced Structural Materials' performed by Argonne National Laboratory (ANL), as part of Advanced Structural Materials Program for the Advanced Reactor Concepts. This work package supports the advanced structural materials development by providing corrosion and tensile data from the standpoint of sodium compatibility of advanced structural alloys. The scope of work involves exposure of advanced structural alloys such as G92, mod.9Cr-1Mo (G91) ferritic-martensitic steels and HT-UPS austenitic stainless steels to a flowing sodium environment with controlled impurity concentrations. The exposed specimens are analyzed for their corrosion performance, microstructural changes, and tensile behavior. Previous reports examined the thermodynamic and kinetic factors involved in the purity of liquid sodium coolant for sodium reactor applications as well as the design, fabrication, and construction of a forced convection sodium loop for sodium compatibility studies of advanced materials. This report presents the results on corrosion performance, microstructure, and tensile properties of advanced ferritic-martensitic and austenitic alloys exposed to liquid sodium at 550 C for up to 2700 h and at 650 C for up to 5064 h in the forced convection sodium loop. The oxygen content of sodium was controlled by the cold-trapping method to achieve {approx}1 wppm oxygen level. Four alloys were examined, G92 in the normalized and tempered condition (H1 G92), G92 in the cold-rolled condition (H2 G92), G91 in the normalized and tempered condition, and hot-rolled HT-UPS. G91 was included as a reference to compare with advanced alloy, G92. It was found that all four alloys showed weight loss after sodium exposures at 550 and 650 C. The weight loss of the four alloys was comparable after sodium exposures at 550 C; the weight loss of ferritic-martensitic steels, G92 and G91 is more significant than that of austenitic stainless steel, HT-UPS after sodium exposures at 650 C. Sodium exposures up to 2700 h at 550 C had no significant influence on tensile properties, while sodium exposures up to 5064 h at 650 C dramatically lowered the tensile strengths of the four alloys. The ultimate tensile strength of H1 G92, H2 G92, and G91 ferritic-martensitic steels was reduced to as much as nearly half of its initial value after sodium exposures at 650 C. Though the uniform elongation was recovered to some extent, these three ferritic-martensitic steels showed considerable strain softening after sodium exposures. The yield stress of HT-UPS austenitic stainless steel increased, the ultimate tensile strength decreased, and the total elongation was reduced after sodium exposures at 650 C. The dynamic strain aging effect observed in the as-received HT-UPS specimens became less pronounced after sodium exposures at 650 C. Microstructural characterization of sodium-exposed specimens showed no appreciable surface deterioration or grain structure changes under an optical microscope, except for the H2 G92 steel, in which the martensite structure transformed to large grain ferrite after sodium exposures at 650 C. TEM observations of the sodium-exposed H2 G92 steel showed significant recrystallization after sodium exposure for 2700 h at 550 C, and transformation of martensite to ferrite and high density of precipitates in nearly dislocation-free matrix after sodium exposures at 650 C. Further microstructural analysis and evaluation of decarburization/carburization behavior is needed to understand the dramatic changes in the tensile strengths of advanced ferritic-martensitic and austenitic steels after sodium exposures at 650 C.

  10. The Sodium Content of Your Food.

    E-Print Network [OSTI]

    Anonymous,

    1982-01-01T23:59:59.000Z

    are usually processed without added salt. However, starchy vegetables such a s lima beans and peas frequently are sorted in brine before freezing. Frozen vegetables with added sauces, mushrooms or nuts are higher in sodium than plain varieties. Canned... ............................ Canned iced Powdaed. mn-flawred iced. sugarsweetened ......................... Low-calorie iced ....................... Thirst Quencher 1 cup 1 cup 1 cup 1 cup 1 cup 1 cup 1 cup 1 cup 1 cup 1 cup 1 cup 1 cup 1 cup 1 cup 8 fl oz Dairy...

  11. Efficacy of soluble sodium tripolyphosphate amendments for the...

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

    of soluble sodium tripolyphosphate amendments for the in-situ immobilisation of uranium."Environmental Chemistry 4:293-300. Authors: DM Wellman EM Pierce MM Valenta...

  12. aqueous sodium sulfate: Topics by E-print Network

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

    viscosity, 771, for PDMDAAC fractions in sodium chloride solutions by viscosity, size-exclusionchromatography, and light Dubin, Paul D. 32 Structure and Dynamics in Aqueous...

  13. Sodium fast reactor safety and licensing research plan. Volume II.

    SciTech Connect (OSTI)

    Ludewig, H. (Brokhaven National Laboratory, Upton, NY); Powers, D. A.; Hewson, John C.; LaChance, Jeffrey L.; Wright, A. (Argonne National Laboratory, Argonne, IL); Phillips, J.; Zeyen, R. (Institute for Energy Petten, Saint-Paul-lez-Durance, France); Clement, B. (IRSN/DPAM.SEMIC Bt 702, Saint-Paul-lez-Durance, France); Garner, Frank (Radiation Effects Consulting, Richland, WA); Walters, Leon (Advanced Reactor Concepts, Los Alamos, NM); Wright, Steve; Ott, Larry J. (Oak Ridge National Laboratory, Oak Ridge, TN); Suo-Anttila, Ahti Jorma; Denning, Richard (Ohio State University, Columbus, OH); Ohshima, Hiroyuki (Japan Atomic Energy Agency, Ibaraki, Japan); Ohno, S. (Japan Atomic Energy Agency, Ibaraki, Japan); Miyhara, S. (Japan Atomic Energy Agency, Ibaraki, Japan); Yacout, Abdellatif (Argonne National Laboratory, Argonne, IL); Farmer, M. (Argonne National Laboratory, Argonne, IL); Wade, D. (Argonne National Laboratory, Argonne, IL); Grandy, C. (Argonne National Laboratory, Argonne, IL); Schmidt, R.; Cahalen, J. (Argonne National Laboratory, Argonne, IL); Olivier, Tara Jean; Budnitz, R. (Lawrence Berkeley National Laboratory, Berkeley, CA); Tobita, Yoshiharu (Japan Atomic Energy Agency, Ibaraki, Japan); Serre, Frederic (Centre d'%C3%94etudes nucl%C3%94eaires de Cadarache, Cea, France); Natesan, Ken (Argonne National Laboratory, Argonne, IL); Carbajo, Juan J. (Oak Ridge National Laboratory, Oak Ridge, TN); Jeong, Hae-Yong (Korea Atomic Energy Research Institute, Daejeon, Korea); Wigeland, Roald (Idaho National Laboratory, Idaho Falls, ID); Corradini, Michael (University of Wisconsin-Madison, Madison, WI); Thomas, Justin (Argonne National Laboratory, Argonne, IL); Wei, Tom (Argonne National Laboratory, Argonne, IL); Sofu, Tanju (Argonne National Laboratory, Argonne, IL); Flanagan, George F. (Oak Ridge National Laboratory, Oak Ridge, TN); Bari, R. (Brokhaven National Laboratory, Upton, NY); Porter D. (Idaho National Laboratory, Idaho Falls, ID); Lambert, J. (Argonne National Laboratory, Argonne, IL); Hayes, S. (Idaho National Laboratory, Idaho Falls, ID); Sackett, J. (Idaho National Laboratory, Idaho Falls, ID); Denman, Matthew R.

    2012-05-01T23:59:59.000Z

    Expert panels comprised of subject matter experts identified at the U.S. National Laboratories (SNL, ANL, INL, ORNL, LBL, and BNL), universities (University of Wisconsin and Ohio State University), international agencies (IRSN, CEA, JAEA, KAERI, and JRC-IE) and private consultation companies (Radiation Effects Consulting) were assembled to perform a gap analysis for sodium fast reactor licensing. Expert-opinion elicitation was performed to qualitatively assess the current state of sodium fast reactor technologies. Five independent gap analyses were performed resulting in the following topical reports: (1) Accident Initiators and Sequences (i.e., Initiators/Sequences Technology Gap Analysis), (2) Sodium Technology Phenomena (i.e., Advanced Burner Reactor Sodium Technology Gap Analysis), (3) Fuels and Materials (i.e., Sodium Fast Reactor Fuels and Materials: Research Needs), (4) Source Term Characterization (i.e., Advanced Sodium Fast Reactor Accident Source Terms: Research Needs), and (5) Computer Codes and Models (i.e., Sodium Fast Reactor Gaps Analysis of Computer Codes and Models for Accident Analysis and Reactor Safety). Volume II of the Sodium Research Plan consolidates the five gap analysis reports produced by each expert panel, wherein the importance of the identified phenomena and necessities of further experimental research and code development were addressed. The findings from these five reports comprised the basis for the analysis in Sodium Fast Reactor Research Plan Volume I.

  14. Sodium cobalt bronze batteries and a method for making same

    DOE Patents [OSTI]

    Doeff, M.M.; Ma, Y.; Visco, S.J.; DeJonghe, L.

    1999-06-29T23:59:59.000Z

    A solid state secondary battery utilizing a low cost, environmentally sound, sodium cobalt bronze electrode is described. A method is provided for producing same. 11 figs.

  15. INITIATION OF DEGRADATION IN POLYCRYSTALLINE SODIUM-BETA ALUMINA ELECTROLYTES

    E-Print Network [OSTI]

    De Jonghe, L.C.

    2010-01-01T23:59:59.000Z

    boundaries. XBB 804 4130 2B Degradation initiation at 300 C,the Proceedings INITIATION OF DEGRADATION IN POLYCRYSTALLINEs w a m INITIATION OF DEGRADATION IN POLYCRYSTALLINE SODIUM-

  16. United States, France and Japan Increase Cooperation on Sodium...

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

    together to establish design goals and high-level requirements for sodium-cooled fast reactor prototypes; identify common safety principles and key technical innovations to...

  17. Chemoradiotherapeutic wrinkled mesoporous silica nanoparticles for use in cancer therapy

    SciTech Connect (OSTI)

    Munaweera, Imalka; Balkus, Kenneth J. Jr., E-mail: Balkus@utdallas.edu, E-mail: Anthony.DiPasqua@unthsc.edu [Department of Chemistry, University of Texas at Dallas, 800 West Campbell Rd., Richardson, Texas 75080 (United States); Koneru, Bhuvaneswari; Shi, Yi; Di Pasqua, Anthony J., E-mail: Balkus@utdallas.edu, E-mail: Anthony.DiPasqua@unthsc.edu [Department of Pharmaceutical Sciences, University of North Texas System College of Pharmacy, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, Texas 76107 (United States)

    2014-11-01T23:59:59.000Z

    Over the last decade, the development and application of nanotechnology in cancer detection, diagnosis, and therapy have been widely reported. Engineering of vehicles for the simultaneous delivery of chemo- and radiotherapeutics increases the effectiveness of the therapy and reduces the dosage of each individual drug required to produce an observable therapeutic response. We here developed a novel chemoradiotherapeutic 1,2-dioleoyl-sn-glycero-3-phosphocholine lipid coated/uncoated platinum drug loaded, holmium-containing, wrinkled mesoporous silica nanoparticle. The materials were characterized with TEM, FTIR, {sup 1}H NMR, energy dispersive x-ray, inductively coupled plasma-mass spectrometry, and zeta potential measurements. In vitro platinum drug release from both lipid coated and uncoated chemoradiotherapeutic wrinkled mesoporous silica are reported. Various kinetic models were used to analyze the release kinetics. The radioactivity of the chemoradiotherapeutic nanocarriers was measured after neutron-activation.

  18. Molecular engineering of porous silica using aryl templates

    DOE Patents [OSTI]

    Loy, D.A.; Shea, K.J.

    1994-06-14T23:59:59.000Z

    A process is described for manipulating the porosity of silica using a series of organic template groups covalently incorporated into the silicate matrix. The templates in the bridged polysilsesquioxanes are selectively removed from the material by oxidation with oxygen plasma or other means, leaving engineered voids or pores. The size of these pores is dependent upon the length or size of the template or spacer. The size of the templates is measured in terms of Si-Si distances which range from about 0.67 nm to 1.08 nm. Changes introduced by the loss of the templates result in a narrow range of micropores (i.e. <2 nm). Both aryl and alkyl template groups are used as spacers. Novel microporous silica materials useful as molecular sieves, desiccants, and catalyst supports are produced. 3 figs.

  19. Molecular engineering of porous silica using aryl templates

    DOE Patents [OSTI]

    Loy, Douglas A. (Albuquerque, NM); Shea, Kenneth J. (Irvine, CA)

    1994-01-01T23:59:59.000Z

    A process for manipulating the porosity of silica using a series of organic template groups covalently incorporated into the silicate matrix. The templates in the bridged polysilsesquioxanes are selectively removed from the material by oxidation with oxygen plasma or other means, leaving engineered voids or pores. The size of these pores is dependent upon the length or size of the template or spacer. The size of the templates is measured in terms of Si-Si distances which range from about 0.67 nm to 1.08 nm. Changes introduced by the loss of the templates result in a narrow range of micropores (i.e. <2 nm). Both aryl and alkyl template groups are used as spacers. Novel microporous silica materials useful as molecular seives, dessicants, and catalyst supports are produced.

  20. Silica aerogels modified by functional and nonfunctional organic groups

    SciTech Connect (OSTI)

    Schubert, U.; Huesing, N.; Schwertfeger, F. [Universitaet Wien (Austria)

    1996-12-31T23:59:59.000Z

    Organically substituted silica aerogels were prepared from RSi(OR`){sub 3}/Si(OR`){sub 4} mixtures, followed by supercritical drying. The typical microstructure and the resulting physical properties of silica aerogels are retained, if the portion of R-Si units is below 10-20%. However, new properties are supplemented, such as hydrophobicity (which makes the aerogels insensitive towards moisture), a higher compliance, and the possibility to incorporate functional organic groups. Controlled pyrolysis of the organically substituted aerogels allows to coat the inner surface of the aerogels with nanometer-sized carbon structures. This results in a very efficient infrared opacification and improved heat insulation properties at high temperatures. 5 refs., 2 figs.

  1. Sodium dichromate expedited response action assessment

    SciTech Connect (OSTI)

    Not Available

    1993-09-01T23:59:59.000Z

    The US Environmental Protection Agency (EPA) and Washington Department of Ecology (Ecology) recommended that the US Department of Energy (DOE) perform an expedited response action (ERA) for the Sodium Dichromate Barrel Disposal Landfill. The ERA lead regulatory agency is Ecology and EPA is the support agency. The ERA was categorized as non-time-critical, which required preparation of an engineering evaluation and cost analysis (EE/CA). The EE/CA was included in the ERA proposal. The EE/CA is a rapid, focused evaluation of available technologies using specific screening factors to assess feasibility, appropriateness, and cost. The ERA goal is to reduce the potential for any contaminant migration from the landfill to the soil column, groundwater, and Columbia River. Since the Sodium Dichromate Barrel Disposal Landfill is the only waste site within the operable unit, the removal action may be the final remediation of the 100-IU-4 Operable Unit. This ERA process started in March 1992. The ERA proposal went through a parallel review process with Westinghouse Hanford Company (WHC), DOE Richland Operations (RL), EPA, Ecology, and a 30-day public comment period. Ecology and EPA issued an Action Agreement Memorandum in March 1993 (Appendix A). The memorandum directed excavation of all anomalies and disposal of the collected materials at the Hanford Site Central Landfill. Primary field activities were completed by the end of April 1993. Final waste disposal of a minor quantity of hazardous waste was completed in July 1993.

  2. Process for manufacturing hollow fused-silica insulator cylinder

    DOE Patents [OSTI]

    Sampayan, Stephen E. (Manteca, CA); Krogh, Michael L. (Lee's Summit, MO); Davis, Steven C. (Lee's Summit, MO); Decker, Derek E. (Discovery Bay, CA); Rosenblum, Ben Z. (Overland Park, KS); Sanders, David M. (Livermore, CA); Elizondo-Decanini, Juan M. (Albuquerque, NM)

    2001-01-01T23:59:59.000Z

    A method for building hollow insulator cylinders that can have each end closed off with a high voltage electrode to contain a vacuum. A series of fused-silica round flat plates are fabricated with a large central hole and equal inside and outside diameters. The thickness of each is related to the electron orbit diameter of electrons that escape the material surface, loop, and return back. Electrons in such electron orbits can support avalanche mechanisms that result in surface flashover. For example, the thickness of each of the fused-silica round flat plates is about 0.5 millimeter. In general, the thinner the better. Metal, such as gold, is deposited onto each top and bottom surface of the fused-silica round flat plates using chemical vapor deposition (CVD). Eutectic metals can also be used with one alloy constituent on the top and the other on the bottom. The CVD, or a separate diffusion step, can be used to defuse the deposited metal deep into each fused-silica round flat plate. The conductive layer may also be applied by ion implantation or gas diffusion into the surface. The resulting structure may then be fused together into an insulator stack. The coated plates are aligned and then stacked, head-to-toe. Such stack is heated and pressed together enough to cause the metal interfaces to fuse, e.g., by welding, brazing or eutectic bonding. Such fusing is preferably complete enough to maintain a vacuum within the inner core of the assembled structure. A hollow cylinder structure results that can be used as a core liner in a dielectric wall accelerator and as a vacuum envelope for a vacuum tube device where the voltage gradients exceed 150 kV/cm.

  3. Silica aerogel: An intrinsically low dielectric constant material

    SciTech Connect (OSTI)

    Hrubesh, L.W.

    1995-04-01T23:59:59.000Z

    Silica aerogels are highly porous solids having unique morphologies in wavelength of visible which both the pores and particles have sizes less than the wavelength of visible light. This fine nanostructure modifies the normal transport mechanisms within aerogels and endows them with a variety of exceptional physical properties. For example, aerogels have the lowest measured thermal conductivity and dielectric constant for any solid material. The intrinsically low dielectric properties of silica aerogels are the direct result of the extremely high achievable porosities, which are controllable over a range from 75% to more than 99.8 %, and which result in measured dielectric constants from 2.0 to less than 1.01. This paper discusses the synthesis of silica aerogels, processing them as thin films, and characterizing their dielectric properties. Existing data and other physical characteristics of bulk aerogels (e.g., thermal stablity, thermal expansion, moisture adsorption, modulus, dielectric strength, etc.), which are useful for evaluating them as potential dielectrics for microelectronics, are also given.

  4. Silylation of low-density silica and bridged polysilsesquioxane aerogels

    SciTech Connect (OSTI)

    DeFriend, K. A. (Kimberly A.); Loy, D. A. (Douglas A.); Salazar, K. V. (Kenneth V.); Wilson, K. V. (Kennard V.)

    2004-01-01T23:59:59.000Z

    Silica and bridged polysilsesquioxane aerogels are low-density materials that are attractive for applications such as thermal insulation, porous separation media or catalyst supports, adsorbents, and cometary dust capture agents. However, aerogels are notoriously weak and brittle making it difficult to handle and machine monoliths into desired forms. This complication prevents the development of many applications that would otherwise benefit from the use of the low-density materials. Here, we will describe our efforts to chemically modify and mechanically enhance silica-based aerogels using chemical vapor techniques without sacrificing their characteristic low densities. Monolithic silica and organic-bridged polysilsesquioxane aerogels were prepared by sol-gel polymerization of the respective methoxysilane monomers followed by supercritical carbon dioxide drying of the gels. Then the gels were reactively modified with silylating agents to demonstrate the viability of CVD modification of aerogels, and to determine the effects of silylation of surface silanols on the morphology, surface area, and mechanical properties of the resulting aerogels.

  5. Antireflective graded index silica coating, method for making

    DOE Patents [OSTI]

    Yoldas, Bulent E. (Churchill, PA); Partlow, Deborah P. (Wilkinsburg, PA)

    1985-01-01T23:59:59.000Z

    Antireflective silica coating for vitreous material is substantially non-reflecting over a wide band of radiations. This is achieved by providing the coating with a graded degree of porosity which grades the index of refraction between that of air and the vitreous material of the substrate. To prepare the coating, there is first prepared a silicon-alkoxide-based coating solution of particular polymer structure produced by a controlled proportion of water to alkoxide and a controlled concentration of alkoxide to solution, along with a small amount of catalyst. The primary solvent is alcohol and the solution is polymerized and hydrolized under controlled conditions prior to use. The prepared solution is applied as a film to the vitreous substrate and rapidly dried. It is thereafter heated under controlled conditions to volatilize the hydroxyl radicals and organics therefrom and then to produce a suitable pore morphology in the residual porous silica layer. The silica layer is then etched in order to enlarge the pores in a graded fashion, with the largest of the pores remaining being sufficiently small that radiations to be passed through the substrate are not significantly scattered. For use with quartz substrates, extremely durable coatings which display only 0.1% reflectivity have been prepared.

  6. Measurement of Radiation Damage on Silica Aerogel Cerenkov Radiator

    E-Print Network [OSTI]

    Belle Preprint; Sahu Wang; M. Z. Wang; R. Suda; R. Enomoto; K. C. Peng; C. H. Wang; I. Adachi; M. Amami

    We measured the radiation damage on silica aerogel Cerenkov radiators originally developed for the B-factory experiment at KEK. Refractive index of the aerogel samples ranged from 1.012 to 1.028. The samples were irradiated up to 9.8 MRad of equivalent dose. Measurements of transmittance and refractive index were carried out and these samples were found to be radiation hard. Deteriorations in transparency and changes of refractive index were observed to be less than 1.3% and 0.001 at 90% confidence level, respectively. Prospects of using aerogels under high-radiation environment are discussed. 1 Introduction Silica aerogels(aerogels) are a colloidal form of glass, in which globules of silica are connected in three dimensional networks with siloxan bonds. They are solid, very light, transparent and their refractive index can be controlled in the production process. Many high energy and nuclear physics experiments have used aerogels instead of pressurized gas for their Cerenkov coun...

  7. Multimodality Imaging with Silica-Based Targeted Nanoparticle Platforms

    SciTech Connect (OSTI)

    Jason S. Lewis

    2012-04-09T23:59:59.000Z

    Objectives: To synthesize and characterize a C-Dot silica-based nanoparticle containing 'clickable' groups for the subsequent attachment of targeting moieties (e.g., peptides) and multiple contrast agents (e.g., radionuclides with high specific activity) [1,2]. These new constructs will be tested in suitable tumor models in vitro and in vivo to ensure maintenance of target-specificity and high specific activity. Methods: Cy5 dye molecules are cross-linked to a silica precursor which is reacted to form a dye-rich core particle. This core is then encapsulated in a layer of pure silica to create the core-shell C-Dot (Figure 1) [2]. A 'click' chemistry approach has been used to functionalize the silica shell with radionuclides conferring high contrast and specific activity (e.g. 64Cu and 89Zr) and peptides for tumor targeting (e.g. cRGD and octreotate) [3]. Based on the selective Diels-Alder reaction between tetrazine and norbornene, the reaction is bioorthogonal, highyielding, rapid, and water-compatible. This radiolabeling approach has already been employed successfully with both short peptides (e.g. octreotate) and antibodies (e.g. trastuzumab) as model systems for the ultimate labeling of the nanoparticles [1]. Results: PEGylated C-Dots with a Cy5 core and labeled with tetrazine have been synthesized (d = 55 nm, zeta potential = -3 mV) reliably and reproducibly and have been shown to be stable under physiological conditions for up to 1 month. Characterization of the nanoparticles revealed that the immobilized Cy5 dye within the C-Dots exhibited fluorescence intensities over twice that of the fluorophore alone. The nanoparticles were successfully radiolabeled with Cu-64. Efforts toward the conjugation of targeting peptides (e.g. cRGD) are underway. In vitro stability, specificity, and uptake studies as well as in vivo imaging and biodistribution investigations will be presented. Conclusions: C-Dot silica-based nanoparticles offer a robust, versatile, and multi-functional platform to enhance in vivo detection sensitivity and non-invasively assay receptor expression/status of tumor cellular targets, including those of low abundance, using nuclear-NIR fluorescence imaging approaches [2]. Improvements in molecular diagnostics, refined by the availability of nanotechnology platforms, will be a key determinant in driving early-stage disease detection and prevention, ultimately leading to decreases in mortality.

  8. Spatial correlation between chemical and topological defects in vitreous silica: UV-resonance Raman study

    SciTech Connect (OSTI)

    Saito, M., E-mail: makina.saito@elettra.eu; D’Amico, F.; Bencivenga, F.; Cucini, R.; Gessini, A.; Principi, E.; Masciovecchio, C. [Elettra-Sincrotrone Trieste, S. S. 14 Km 163.5, I-34149 Trieste (Italy)

    2014-06-28T23:59:59.000Z

    A spatial correlation between chemical and topological defects in the tetrahedron network in vitreous silica produced by a fusion process of natural quartz crystals was found by synchrotron-based UV resonance Raman experiments. Furthermore, a quantitative correlation between these defects was obtained by comparing visible Raman and UV absorption spectra. These results indicate that in vitreous silica produced by the fusion process the topological defects disturb the surrounding tetrahedral silica network and induce further disorder regions with sub nanometric sizes.

  9. SODIUM CYANIDE AS A FISH POISON Marine Biological Laboratory

    E-Print Network [OSTI]

    SODIUM CYANIDE AS A FISH POISON Marine Biological Laboratory APR 2 '^ 1958 WOODS HOLE, MASS CYANIDE AS A FISH POISON By W. R. Bridges Cooperative Fishery Research Laboratory Southern Illinois as a fish poison. At concentrations of 1 p. p.m. sodium cyanide and at a variety of temperature and p

  10. RESEARCH Open Access Half-molar sodium lactate infusion improves

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    RESEARCH Open Access Half-molar sodium lactate infusion improves cardiac performance in acute heart for the myocardium at rest and during stress. We tested the effects of half-molar sodium lactate infusion on cardiac by 1 ml/kg/h continuous infusion for 24 hours. The control group received only a 3 ml/kg bolus

  11. Synthesis of Mesocellular Silica Foams with Tunable Window and Cell Dimensions

    E-Print Network [OSTI]

    Yang, Peidong

    Polystyrene microspheres coated with cationic surfactants are easily prepared by micro- emulsion templates. These silica foams resemble dense aerogels. Introduction Because of their greatly enhanced pore

  12. Biotransformation of Two-Line Silica-Ferrihydrite by a Dissimilatory...

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

    by a Dissimilatory Fe(III)-Reducing Bacterium: Formation of Carbonate Green Biotransformation of Two-Line Silica-Ferrihydrite by a Dissimilatory Fe(III)-Reducing...

  13. TESLA-FEL 2004-01 Silica Aerogel Radiators for Bunch Length Measurements ?

    E-Print Network [OSTI]

    J. Bähr A; V. Djordjadze A; D. Lipka A; A. Onuchin B; F. Stephan A

    Cherenkov radiators based on Silica aerogel are used to measure the electron bunch length at the photo injector test facility at DESY Zeuthen (PITZ). The energy range of those electrons is 4-5 MeV. In this paper the time resolution defined by the usage of aerogel is calculated analytically and Monte Carlo simulations are performed. It is shown that Silica aerogel gives the possibility to reach a time resolution of about 0.1 ps for high photon intensities and a time resolution of about 0.02 ps can be obtained for thin Silica aerogel radiators. Key words: silica aerogel, bunch length, time resolution, PITZ 1

  14. Low temperature sodium-beta battery

    DOE Patents [OSTI]

    Farmer, Joseph C

    2013-11-19T23:59:59.000Z

    A battery that will operate at ambient temperature or lower includes an enclosure, a current collector within the enclosure, an anode that will operate at ambient temperature or lower within the enclosure, a cathode that will operate at ambient temperature or lower within the enclosure, and a separator and electrolyte within the enclosure between the anode and the cathode. The anode is a sodium eutectic anode that will operate at ambient temperature or lower and is made of a material that is in a liquid state at ambient temperature or lower. The cathode is a low melting ion liquid cathode that will operate at ambient temperature or lower and is made of a material that is in a liquid state at ambient temperature or lower.

  15. Production of sodium-22 from proton irradiated aluminum

    DOE Patents [OSTI]

    Taylor, Wayne A. (Los Alamos, NM); Heaton, Richard C. (Los Alamos, NM); Jamriska, David J. (Los Alamos, NM)

    1996-01-01T23:59:59.000Z

    A process for selective separation of sodium-22 from a proton irradiated minum target including dissolving a proton irradiated aluminum target in hydrochloric acid to form a first solution including aluminum ions and sodium ions, separating a portion of the aluminum ions from the first solution by crystallization of an aluminum salt, contacting the remaining first solution with an anion exchange resin whereby ions selected from the group consisting of iron and copper are selectively absorbed by the anion exchange resin while aluminum ions and sodium ions remain in solution, contacting the solution with an cation exchange resin whereby aluminum ions and sodium ions are adsorbed by the cation exchange resin, and, contacting the cation exchange resin with an acid solution capable of selectively separating the adsorbed sodium ions from the cation exchange resin while aluminum ions remain adsorbed on the cation exchange resin is disclosed.

  16. Calcium and sodium bentonite for hydraulic containment applications

    SciTech Connect (OSTI)

    Gleason, M.H. [GeoSyntec Consultants, Columbia, MD (United States); Daniel, D.E. [Univ. of Illinois, Urbana, IL (United States). Dept. of Civil Engineering; Eykholt, G.R. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Civil Engineering

    1997-05-01T23:59:59.000Z

    The hydraulic conductivity of calcium and sodium bentonites was investigated for sand-bentonite mixtures, a thin bentonite layer simulating a geosynthetic clay liner (GCL), and bentonite-cement mixtures simulating backfill for a vertical cutoff wall. The permeant liquids were tap water and distilled water containing 0.25 M calcium chloride. In general, the hydraulic performance of calcium bentonite was not significantly better than the performance of sodium bentonite for either the clay-amended sand or the GCL application, and was substantially worse than the performance of sodium bentonite in the bentonite-cement mixture. A drained angle of internal friction of 21{degree} was measured for calcium bentonite, compared to 10{degree} for sodium bentonite. Except for a larger drained shear strength, no advantage of calcium bentonite over sodium bentonite could be identified from the results of this study.

  17. Decommissioning of Experimental Breeder Reactor - II Complex, Post Sodium Draining

    SciTech Connect (OSTI)

    J. A. (Bart) Michelbacher; S. Paul Henslee; Collin J. Knight; Steven R. sherman

    2005-09-01T23:59:59.000Z

    The Experimental Breeder Reactor - II (EBR-II) was shutdown in September 1994 as mandated by the United States Department of Energy. This sodium-cooled reactor had been in service since 1964. The bulk sodium was drained from the primary and secondary systems and processed. Residual sodium remaining in the systems after draining was converted into sodium bicarbonate using humid carbon dioxide. This technique was tested at Argonne National Laboratory in Illinois under controlled conditions, then demonstrated on a larger scale by treating residual sodium within the EBR-II secondary cooling system, followed by the primary tank. This process, terminated in 2002, was used to place a layer of sodium bicarbonate over all exposed surfaces of sodium. Treatment of the remaining EBR-II sodium is governed by the Resource Conservation and Recovery Act (RCRA). The Idaho Department of Environmental Quality issued a RCRA Operating Permit in 2002, mandating that all hazardous materials be removed from EBR-II within a 10 year period, with the ability to extend the permit and treatment period for another 10 years. A preliminary plan has been formulated to remove the remaining sodium and NaK from the primary and secondary systems using moist carbon dioxide, steam and nitrogen, and a water flush. The moist carbon dioxide treatment was resumed in May 2004. As of August 2005, approximately 60% of the residual sodium within the EBR-II primary tank had been treated. This process will continue through the end of 2005, when it is forecast that the process will become increasingly ineffective. At that time, subsequent treatment processes will be planned and initiated. It should be noted that the processes and anticipated costs associated with these processes are preliminary. Detailed engineering has not been performed, and approval for these methods has not been obtained from the regulator or the sponsors.

  18. E-Print Network 3.0 - acetate sodium lactate Sample Search Results

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

    sodium-high lactate infusion'. Of course, it is easy to demonstrate that high lactate infusion... . Also, sodium-lactate infusion in humans ... Source: Ecole Polytechnique, Centre...

  19. Association of length-slow silica with evaporites

    SciTech Connect (OSTI)

    Heaney, P.J. (Princeton Univ., Princeton, NJ (United States). Dept. of Geology); Sheppard, R.A. (Geological Survey, Denver, CO (United States). Denver Federal Center); Post, J.E. (Smithsonian Inst., Washington, DC (United States). Dept. of Mineral Sciences)

    1992-01-01T23:59:59.000Z

    In 1971, Folk and Pittman described the common occurrence of length-slow quartz (or lutecite) with evaporitic minerals, and they suggested that lutecite might be a useful indicator for vanished evaporites. However, the subsequent discoveries of length-slow silica in carbonate turbidites and in abyssal Pacific cherts revealed that lutecite is not restricted to near-surface deposits. Moreover, Kastner found that length-slow quartz could be crystallized in slightly alkaline solutions enriched in Mg[sup 2+], Na[sup +], and SO[sub 4][sup [minus]2]. Following these studies, researchers have cited the presence of lutecite in rock samples as suggestive but not compelling evidence for an evaporitic origin, and the precise nature of this form of silica has remained somewhat enigmatic. Investigations of chert nodules from evaporitic and non-evaporitic regimes support an identification of length-slow quartz'' with the mineral moganite, a polymorph of silica that is fibrous and optically length slow. Results are based upon X-ray powder diffraction of the chert, followed by Rietveld refinement of the X-ray patterns to quantify the weight fraction of quartz and moganite in each specimen. Most non-evaporitic chert appears to contain between 5 and 15 wt. % moganite, but evaporitic cherts often contain more than 20 wt. %. Cherts that have transformed from precursor magadiite can be particularly rich in moganite; samples from Lake Magadi, Kenya and from Harney Lake, Oregon revealed about equal parts moganite and quartz. However, the observation of decreasing abundances of moganite in rocks of increasing age indicates that moganite is metastable relative to quartz.

  20. Thermal annealing of laser damage precursors on fused silica surfaces

    SciTech Connect (OSTI)

    Shen, N; Miller, P E; Bude, J D; Laurence, T A; Suratwala, T I; Steele, W A; Feit, M D; Wang, L L

    2012-03-19T23:59:59.000Z

    Previous studies have identified two significant precursors of laser damage on fused silica surfaces at fluenes below {approx} 35 J/cm{sup 2}, photoactive impurities in the polishing layer and surface fractures. In the present work, isothermal heating is studied as a means of remediating the highly absorptive, defect structure associated with surface fractures. A series of Vickers indentations were applied to silica surfaces at loads between 0.5N and 10N creating fracture networks between {approx} 10{micro}m and {approx} 50{micro}m in diameter. The indentations were characterized prior to and following thermal annealing under various times and temperature conditions using confocal time-resolved photo-luminescence (CTP) imaging, and R/1 optical damage testing with 3ns, 355nm laser pulses. Significant improvements in the damage thresholds, together with corresponding reductions in CTP intensity, were observed at temperatures well below the glass transition temperature (T{sub g}). For example, the damage threshold on 05.N indentations which typically initiates at fluences <8 J/cm{sup 2} could be improved >35 J/cm{sup 2} through the use of a {approx} 750 C thermal treatment. Larger fracture networks required longer or higher temperature treatment to achieve similar results. At an annealing temperature > 1100 C, optical microscopy indicates morphological changes in some of the fracture structure of indentations, although remnants of the original fracture and significant deformation was still observed after thermal annealing. This study demonstrates the potential of using isothermal annealing as a means of improving the laser damage resistance of fused silica optical components. Similarly, it provides a means of further understanding the physics associated with optical damage and related mitigation processes.

  1. Hazard categorization and classification for the sodium storage facility

    SciTech Connect (OSTI)

    Van Keuren, J.C.

    1994-08-30T23:59:59.000Z

    The Sodium Storage Facility is planned to be constructed in the 400 area for long term storage of sodium from the Fast Flux Test Facility (FFTF). It will contain four large sodium storage tanks. Three of the tanks have a capacity of 80,000 gallons of sodium each, and the fourth will hold 52,500 gallons. The tanks will be connected by piping with each other and to the FFTF. Sodium from the FFTF primary and secondary Heat Transport Systems (HTS), Interim Decay Storage (IDS), and the Fuel Storage Facility (FSF) will be transferred to the facility, and stored there in a frozen state pending final disposition. A Hazard Classification has been performed in order to evaluate the potential toxic consequences of a sodium fire according to the provisions of DOE Order 5481.1B. The conclusion of these evaluations is that the Sodium Storage Facility meets the requirements of the lowest Hazard Category, i.e., radiological facility, and the Hazard Classification is recommended to be moderate.

  2. Experimental investigations on sodium plugging in narrow flow channels.

    SciTech Connect (OSTI)

    Momozaki, Y.; Cho, D. H.; Sienicki, J. J.; Moisseytsev, A.; Nuclear Engineering Division

    2010-08-01T23:59:59.000Z

    A series of experiments was performed to investigate the potential for plugging of narrow flow channels of sodium by impurities (e.g., oxides). In the first phase of the experiments, clean sodium was circulated through the test sections simulating flow channels in a compact diffusion-bonded heat exchanger such as a printed circuit heat exchanger. The primary objective was to see if small channels whose cross sections are semicircles of 2, 4, and 6 mm in diameter are usable in liquid sodium applications where sodium purity is carefully controlled. It was concluded that the 2-mm channels, the smallest of the three, could be used in clean sodium systems at temperatures even as low as 100 to 110 C without plugging. In the second phase, sodium oxide was added to the loop, and the oxygen concentration in the liquid sodium was controlled by means of varying the cold-trap temperature. Intentional plugging was induced by creating a cold spot in the test sections, and the subsequent plugging behavior was observed. It was found that plugging in the 2-mm test section was initiated by lowering the cold spot temperature below the cold-trap temperature by 10 to 30 C. Unplugging of the plugged channels was accomplished by heating the affected test section.

  3. The production of activated silica with carbon dioxide gas

    E-Print Network [OSTI]

    Hayes, William Bell

    1956-01-01T23:59:59.000Z

    Ional to the per cent of carbon dioxi. de 1n the flue gas for a constant total gas flow rate. REFE REN CES l. Andrews, R. V, , Hanford Works Eocument (1952), 2. Andrews, R. V. & J. A. W. W. A, , ~46 82 (1954). 3. Andrews, R. V, , Personal Communication 4... of the reciuire . ents for the dedree of iliASTER OF SCIENCE Janus', 1956 Major Subject: Chemi. cal Engineering TH PRODUCTION OP ACTIVATED SILICA 7iIITH CARBON DIOXIDE GAS A Thesis William Bell Hayes III Approved as to style and content by: Chairmen...

  4. Chemical treatment for silica-containing glass surfaces

    DOE Patents [OSTI]

    Grabbe, A.; Michalske, T.A.; Smith, W.L.

    1998-04-07T23:59:59.000Z

    Dehydroxylated, silica-containing, glass surfaces are known to be at least partially terminated by strained siloxane rings. According to the invention, a surface of this kind is exposed to a selected silane compound or mixture of silane compounds under reaction-promoting conditions. The ensuing reaction results in opening of the strained siloxane rings, and termination of surface atoms by chemical species, such as organic or organosilicon species, having desirable properties. These species can be chosen to provide qualities such as hydrophobicity, or improved coupling to a polymeric coating. 11 figs.

  5. Chemical treatment for silica-containing glass surfaces

    DOE Patents [OSTI]

    Grabbe, Alexis (Albuquerque, NM); Michalske, Terry Arthur (Cedar Crest, NM); Smith, William Larry (Albuquerque, NM)

    1998-01-01T23:59:59.000Z

    Dehydroxylated, silica-containing, glass surfaces are known to be at least partially terminated by strained siloxane rings. According to the invention, a surface of this kind is exposed to a selected silane compound or mixture of silane compounds under reaction-promoting conditions. The ensuing reaction results in opening of the strained siloxane rings, and termination of surface atoms by chemical species, such as organic or organosilicon species, having desirable properties. These species can be chosen to provide qualities such as hydrophobicity, or improved coupling to a polymeric coating.

  6. Method for chemical surface modification of fumed silica particles

    DOE Patents [OSTI]

    Grabbe, Alexis (Albuquerque, NM); Michalske, Terry Arthur (Cedar Crest, NM); Smith, William Larry (Albuquerque, NM)

    1999-01-01T23:59:59.000Z

    Dehydroxylated, silica-containing, glass surfaces are known to be at least partially terminated by strained siloxane rings. According to the invention, a surface of this kind is exposed to a selected silane compound or mixture of silane compounds under reaction-promoting conditions. The ensuing reaction results in opening of the strained siloxane rings, and termination of surface atoms by chemical species, such as organic or organosilicon species, having desirable properties. These species can be chosen to provide qualities such as hydrophobicity, or improved coupling to a polymeric coating.

  7. Chemical treatment for silica-containing glass surfaces

    DOE Patents [OSTI]

    Grabbe, Alexis (Albuquerque, NM); Michalske, Terry Arthur (Cedar Crest, NM); Smith, William Larry (Albuquerque, NM)

    1999-01-01T23:59:59.000Z

    Dehydroxylated, silica-containing, glass surfaces are known to be at least partially terminated by strained siloxane rings. According to the invention, a surface of this kind is exposed to a selected silane compound or mixture of silane compounds under reaction-promoting conditons. The ensuing reaction results in opening of the strained siloxane rings, and termination of surface atoms by chemical species, such as organic or organosilicon species, having desirable properties. These species can be chosen to provide qualities such as hydrophobicity, or improved coupling to a polymeric coating.

  8. Method for chemical surface modification of fumed silica particles

    DOE Patents [OSTI]

    Grabbe, A.; Michalske, T.A.; Smith, W.L.

    1999-05-11T23:59:59.000Z

    Dehydroxylated, silica-containing, glass surfaces are known to be at least partially terminated by strained siloxane rings. According to the invention, a surface of this kind is exposed to a selected silane compound or mixture of silane compounds under reaction-promoting conditions. The ensuing reaction results in opening of the strained siloxane rings, and termination of surface atoms by chemical species, such as organic or organosilicon species, having desirable properties. These species can be chosen to provide qualities such as hydrophobicity, or improved coupling to a polymeric coating. 11 figs.

  9. Chemical treatment for silica-containing glass surfaces

    DOE Patents [OSTI]

    Grabbe, Alexis (Albuquerque, NM); Michalske, Terry Arthur (Bernalillo, NM); Smith, William Larry (Albuquerque, NM)

    1999-01-01T23:59:59.000Z

    Dehydroxylated, silica-containing, glass surfaces are known to be at least partially terminated by strained siloxane rings. According to the invention, a surface of this kind is exposed to a selected silane compound or mixture of silane compounds under reaction-promoting conditions. The ensuing reaction results in opening of the strained siloxane rings, and termination of surface atoms by chemical species, such as organic or organosilicon species, having desirable properties. These species can be chosen to provide qualities such as hydrophobicity, or improved coupling to a polymeric coating.

  10. Optical and radiographical characterization of silica aerogel for Cherenkov radiator

    E-Print Network [OSTI]

    Tabata, Makoto; Hatakeyama, Yoshikiyo; Kawai, Hideyuki; Morita, Takeshi; Nishikawa, Keiko

    2012-01-01T23:59:59.000Z

    We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying method enables us to produce highly transparent hydrophobic aerogels with high refractive index by shrinking wet-gels. In order to investigate the uniformity in the density (i.e., refractive index) of an individual aerogel monolith, we use the laser Fraunhofer method, an X-ray absorption technique, and Cherenkov imaging by a ring imaging Cherenkov detector in a beam test. We observed an increase in density at the edge of the aerogel tiles, produced by pin-drying.

  11. Optical and radiographical characterization of silica aerogel for Cherenkov radiator

    E-Print Network [OSTI]

    Makoto Tabata; Ichiro Adachi; Yoshikiyo Hatakeyama; Hideyuki Kawai; Takeshi Morita; Keiko Nishikawa

    2012-07-17T23:59:59.000Z

    We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying method enables us to produce highly transparent hydrophobic aerogels with high refractive index by shrinking wet-gels. In order to investigate the uniformity in the density (i.e., refractive index) of an individual aerogel monolith, we use the laser Fraunhofer method, an X-ray absorption technique, and Cherenkov imaging by a ring imaging Cherenkov detector in a beam test. We observed an increase in density at the edge of the aerogel tiles, produced by pin-drying.

  12. Preparation of silica aerogels with improved mechanical properties and extremely low thermal conductivities through modified sol-gel process

    E-Print Network [OSTI]

    Zuo, Yanjia

    2010-01-01T23:59:59.000Z

    Reported silica aerogels have a thermal conductivity as low as 15 mW/mK. The fragility of silica aerogels, however, makes them impractical for structural applications. The purpose of the study is to improve the ductility ...

  13. Pulsed infrared laser annealing of gold nanoparticles embedded in a silica A. Halabica,1,a

    E-Print Network [OSTI]

    Pennycook, Steve

    Pulsed infrared laser annealing of gold nanoparticles embedded in a silica matrix A. Halabica,1,a J; published online 28 April 2008 Pulsed infrared laser irradiation was used to modify the optical and physical in a fused-silica matrix. The experiments demonstrate the unique effects of fast thermal heating

  14. DENSIFICATION AS THE ONLY MECHANISM AT STAKE DURING INDENTATION OF SILICA GLASS?

    E-Print Network [OSTI]

    Brest, Université de

    DENSIFICATION AS THE ONLY MECHANISM AT STAKE DURING INDENTATION OF SILICA GLASS? Vincent Keryvin1 mariette.nivard@univ-rennes1.fr, f jean-christophe.sangleboeuf@univ-rennes1.fr Keywords: Indentation; Glass; Densification; Plasticity; Imprint; Modeling; Finite-Element Analysis; Fused quartz Abstract. Silica glass

  15. The effect of silica nanoparticle-modified surfaces on cell morphology, cytoskeletal organization and function

    E-Print Network [OSTI]

    substrates were coated with monodispersed silica nanoparticles of 50, 100 and 300 nm in diameter. The impactThe effect of silica nanoparticle-modified surfaces on cell morphology, cytoskeletal organization investigate the effect of nanoparticle (NP) assemblies arranged on a flat substrate on cytoskeletal

  16. The influence of void space on antireflection coatings of silica nanoparticle self-assembled films

    E-Print Network [OSTI]

    Heflin, Randy

    The influence of void space on antireflection coatings of silica nanoparticle self-assembled films This study investigates the deposition by ionic self-assembly of alternating silica nanoparticle and poly allyamine hydrochloride layers with the goal to create a single-material antireflection coating

  17. Ionic effects on silica optical fiber strength and models for fatigue V. V. Rondinella

    E-Print Network [OSTI]

    Matthewson, M. John

    Ionic effects on silica optical fiber strength and models for fatigue V. V. Rondinella M. J. Matthewson Rutgers University, Fiber Optic Materials Research Program P. 0. Box 909, Piscataway, NJ 08855, flaw free silica optical fiber shows significant differences from the bulk material for poorly

  18. Effects of silica nanoparticle addition to the secondary coating of dual-coated optical fibers

    E-Print Network [OSTI]

    Matthewson, M. John

    Effects of silica nanoparticle addition to the secondary coating of dual-coated optical fibers J Available online 30 March 2006 Abstract The mechanical and optical properties of dual-coated optical fibers of silica nanoparticles in the secondary coating is shown to enhance the resistance of optical fibers

  19. Effect of chemical stripping on the strength and surface morphology of fused silica optical fiber

    E-Print Network [OSTI]

    Matthewson, M. John

    Effect of chemical stripping on the strength and surface morphology of fused silica optical fiber V. V. Rondinella M. J. Matthewson Fiber Optic Materials Research Program Department of Ceramics Rutgers University, Piscataway, NJ 08855-0909 ABSTRACT Examination of the surface profile of silica optical fiber

  20. Developing a process for commercial silica production from Salton Sea brines

    SciTech Connect (OSTI)

    Bourcier, W; McCutcheon, M; Leif, R; Bruton, C

    2000-09-25T23:59:59.000Z

    The goal of this joint LLNL-CalEnergy project is to develop a method for precipitating marketable silica from spent Salton Sea Geothermal Field (SSGF) brines. Many markets for silica exist. We have initially targeted production of silica as a rubber additive. Silica reinforced rubber gives tires less rolling resistance, greater tear strength, and better adhesion to steel belts. Previous silica precipitates produced by CalEnergy from Salton Sea brines were not suitable as rubber additives. They did not to disperse well in the rubber precursors and produced inferior rubber. CalEnergy currently minimizes silica scaling in some of their production facilities by acidifying the brine pH. The rate of silica precipitation slows down as the pH is lowered, so that energy extraction and brine reinfection are possible without unacceptable amounts of scaling even with more than 700 ppm SiO{sub 2} in solution. We are adding a step in which a small amount of base is added to the acidified brine to precipitate silica before reinfection. By carefully controlling the type, rate, and amount of base addition, we can optimize the properties of the precipitate to approach those of an ideal rubber additive.

  1. DOI: 10.1002/adma.200701303 Nanolayered Carbon/Silica Superstructures via Organosilane

    E-Print Network [OSTI]

    Zhu, Yuntian T.

    . A main advantage using mesoporous silica is to synthesize carbon/silica composite materials with tunable of amorphous carbon materials after carbonization, and uncontrolled morphologies of composite materials is typically high. However, the composites are not uniform; car- bonization mainly produces amorphous carbon

  2. Titanium-assisted growth of silica nanowires: from surface-matched to free-standing morphologies

    E-Print Network [OSTI]

    Nabben, Reinhard

    Titanium-assisted growth of silica nanowires: from surface-matched to free-standing morphologies.1088/0957-4484/22/40/405604 Titanium-assisted growth of silica nanowires: from surface-matched to free-standing morphologies G Callsen1

  3. Integrated Optical Orbital Angular Momentum Multiplexing Device using 3-D Waveguides and a Silica PLC

    E-Print Network [OSTI]

    Yoo, S. J. Ben

    PLC Binbin Guan,1 Ryan P. Scott,1 Nicolas K. Fontaine,2 Tiehui Su,1 Carlo Ferrari,3 Mark Cappuzzo,3 on a silica planar lightwave circuit (PLC) coupled to a 3-D photonic circuit that efficiently generates planar lightwave circuit (PLC) with a silica 3-D PIC that supports up to 15 OAM modes, both TE and TM

  4. ORIGINAL PAPER Algal-silica cycling and pigment diagenesis in recent alpine

    E-Print Network [OSTI]

    Konhauser, Kurt

    dis- solved within 50 years of deposition. Diatom dissolu- tion, silica recycling, and diageneticO2, hereafter BSi) in lake sediments that has led to their common use in freshwater paleoecology have the lowest preservation potential for diatom frustules. However, the recycling of diatom silica

  5. Modification of Silica Nanoparticles by Grafting of Copolymers Containing Organosilane and Fluorine Moities.

    E-Print Network [OSTI]

    Boyer, Edmond

    .23513 #12;2 Introduction Organic polymer / inorganic hybrid nanocomposites are of current research/silica weight ratio until a maximum value of 2.26 mol.m-2 . Keywords: cotelomerization; grafting onto; hybrid nanoparticle; perfluoroacrylate; silica nanocomposite. hal-00412444,version1-1Sep2009 Author manuscript

  6. Characterization of zirconia- and niobia-silica mixture coatings produced by ion-beam sputtering

    SciTech Connect (OSTI)

    Melninkaitis, Andrius; Tolenis, Tomas; Mazule, Lina; Mirauskas, Julius; Sirutkaitis, Valdas; Mangote, Benoit; Fu Xinghai; Zerrad, Myriam; Gallais, Laurent; Commandre, Mireille; Kicas, Simonas; Drazdys, Ramutis

    2011-03-20T23:59:59.000Z

    ZrO{sub 2}-SiO{sub 2} and Nb{sub 2}O{sub 5}-SiO{sub 2} mixture coatings as well as those of pure zirconia (ZrO{sub 2}), niobia (Nb{sub 2}O{sub 5}), and silica (SiO{sub 2}) deposited by ion-beam sputtering were investigated. Refractive-index dispersions, bandgaps, and volumetric fractions of materials in mixed coatings were analyzed from spectrophotometric data. Optical scattering, surface roughness, nanostructure, and optical resistance were also studied. Zirconia-silica mixtures experience the transition from crystalline to amorphous phase by increasing the content of SiO{sub 2}. This also results in reduced surface roughness. All niobia and silica coatings and their mixtures were amorphous. The obtained laser-induced damage thresholds in the subpicosecond range also correlates with respect to the silica content in both zirconia- and niobia-silica mixtures.

  7. Risk Management for Sodium Fast Reactors.

    SciTech Connect (OSTI)

    Denman, Matthew R; Groth, Katrina; Cardoni, Jeffrey N; Wheeler, Timothy A.

    2015-01-01T23:59:59.000Z

    Accident management is an important component to maintaining risk at acceptable levels for all complex systems, such as nuclear power plants. With the introduction of self - correcting, or inherently safe, reactor designs the focus has shifted from management by operators to allowing the syste m's design to manage the accident. While inherently and passively safe designs are laudable, extreme boundary conditions can interfere with the design attributes which facilitate inherent safety , thus resulting in unanticipated and undesirable end states. This report examines an inherently safe and small sodium fast reactor experiencing a beyond design basis seismic event with the intend of exploring two issues : (1) can human intervention either improve or worsen the potential end states and (2) can a Bayes ian Network be constructed to infer the state of the reactor to inform (1). ACKNOWLEDGEMENTS The author s would like to acknowledge the U.S. Department of E nergy's Office of Nuclear Energy for funding this research through Work Package SR - 14SN100303 under the Advanced Reactor Concepts program. The authors also acknowledge the PRA teams at A rgonne N ational L aborator y , O ak R idge N ational L aborator y , and I daho N ational L aborator y for their continue d contributions to the advanced reactor PRA mission area.

  8. Terahertz Time-Domain Spectroscopy Study of Silica Aerogels and Adsorbed Molecular Jiangquan Zhang and D. Grischkowsky*

    E-Print Network [OSTI]

    Terahertz Time-Domain Spectroscopy Study of Silica Aerogels and Adsorbed Molecular Vapors Jiangquan time-domain spectroscopy (THz-TDS) study of hydrophobic and hydrophilic silica aerogels, and the adsorption of several molecular vapors in the hydrophilic silica aerogel. The hydrophobic and hydrophilic

  9. Aluminum and silica intake in drinking water and the risk of Alzheimer's disease or cognitive decline: findings of the

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Aluminum and silica intake in drinking water and the risk of Alzheimer's disease or cognitive,2 , Commenges Daniel1,2 , Helmer Catherine2,3 , Jean-François Dartigues2,3 . Abbreviations: Al, Aluminum; AD, Alzheimer's Disease; MMSE, Mini Mental State Examination; Si, Silica Running head: Aluminum, silica in water

  10. Fluorescent single walled nanotube/silica composite materials

    SciTech Connect (OSTI)

    Dattelbaum, Andrew M.; Gupta, Gautam; Duque, Juan G.; Doorn, Stephen K.; Hamilton, Christopher E.; DeFriend Obrey, Kimberly A.

    2013-03-12T23:59:59.000Z

    Fluorescent composites of surfactant-wrapped single-walled carbon nanotubes (SWNTs) were prepared by exposing suspensions of surfactant-wrapped carbon nanotubes to tetramethylorthosilicate (TMOS) vapor. Sodium deoxycholate (DOC) and sodium dodecylsulphate (SDS) were the surfactants. No loss in emission intensity was observed when the suspension of DOC-wrapped SWNTs were exposed to the TMOS vapors, but about a 50% decrease in the emission signal was observed from the SDS-wrapped SWNTs nanotubes. The decrease in emission was minimal by buffering the SDS/SWNT suspension prior to forming the composite. Fluorescent xerogels were prepared by adding glycerol to the SWNT suspensions prior to TMOS vapor exposure, followed by drying the gels. Fluorescent aerogels were prepared by replacing water in the gels with methanol and then exposing them to supercritical fluid drying conditions. The aerogels can be used for gas sensing.

  11. The LHCb RICH silica aerogel performance with LHC data

    E-Print Network [OSTI]

    Perego, D L

    2010-01-01T23:59:59.000Z

    In the LHCb detector at the Large Hadron Collider, powerful charged particle identification is performed by Ring Imaging Cherenkov (RICH) technology. In order to cover the full geometric acceptance and the wide momentum range (1-100 GeV/c), two detectors with three Cherenkov radiators have been designed and installed. In the medium (10-40 GeV/c) and high (30-100 GeV/c) momentum range, gas radiators are used (C4F10 and CF4 respectively). In the low momentum range (1 to a few GeV/c) pion/kaon/proton separation will be done with photons produced in solid silica aerogel. A set of 16 tiles, with the large transverse dimensions ever (20x20 cm$^2$) and nominal refractive index 1.03 have been produced. The tiles have excellent optical properties and homogeneity of refractive index within the tile of ~1%. The first data collected at LHC are used to understand the behaviour of the RICH: preliminary results will be presented and discussed on the performance of silica aerogel and of the gas radiators C4F10 and CF4.

  12. Synthesis and properties of Chitosan-silica hybrid aerogels

    SciTech Connect (OSTI)

    Ayers, Michael R.; Hunt, Arlon J.

    2001-06-01T23:59:59.000Z

    Chitosan, a polymer that is soluble in dilute aqueous acid, is derived from chitin, a natural polyglucosamide. Aquagels where the solid phase consists of both chitosan and silica can be easily prepared by using an acidic solution of chitosan to catalyze the hydrolysis and condensation of tetraethylorthosilicate. Gels with chitosan/TEOS mass ratios of 0.1-1.1 have been prepared by this method. Standard drying processes using CO{sub 2} give the corresponding aerogels. The amount of chitosan in the gel plays a role in the shrinkage of the aerogel during drying. Gels with the lowest chitosan/silica ratios show the most linear shrinkage, up to 24%, while those with the highest ratios show only a 7% linear shrinkage. Pyrolysis at 700 C under nitrogen produces a darkened aerogel due to the thermal decomposition of the chitosan, however, the aerogel retains its monolithic form. The pyrolyzed aerogels absorb slightly more infrared radiation in the 2-5 {micro}m region than the original aerogels. B.E.T. surface areas of these aerogels range from 470-750 m{sup 2}/g. Biocompatibility screening of this material shows a very high value for hemolysis, but a low value for cytotoxicity.

  13. Sodium Ion Insertion in Hollow Carbon Nanowires for Battery Applicatio...

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

    B Schwenzer, J Xiao, Z Nie, LV Saraf, Z Yang, and J Liu.2012."Sodium Ion Insertion in Hollow Carbon Nanowires for Battery Applications."Nano Letters 12(7):37833787....

  14. Title of dissertation: HYDROMAGNETIC TURBULENT INSTABILITY IN LIQUID SODIUM

    E-Print Network [OSTI]

    Lathrop, Daniel P.

    ABSTRACT Title of dissertation: HYDROMAGNETIC TURBULENT INSTABILITY IN LIQUID SODIUM EXPERIMENTS Daniel R. Sisan, Doctor of Philosophy, 2004 Dissertation directed by: Professor Daniel P. Lathrop Department of Physics This dissertation describes the observation of magnetically-induced instabil- ities

  15. aged sodium borophosphate: Topics by E-print Network

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

    ultraviolet flux will produce a similar variation in the column of neutral sodium for a fixed mass flux and density. However, if the cold gas is in pressure equilibrium with a hot...

  16. Sodium-cooled Fast Reactor - Past and Future | Argonne National...

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

    Sodium-cooled Fast Reactor - Past and Future June 16, 2015 10:00AM to 11:00AM Presenter Taek K. Kim (NE), Principal Nuclear Engineer and Department Manager Location Building 205,...

  17. aluminum sodium chloride: Topics by E-print Network

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

    made with either sodium chloride or potassium chloride. The addition of 75 or 150 porn N02 did not lower plate counts (P&0. 05... Kayfus, Timothy Jon 2012-06-07 47...

  18. aerated sodium chloride: Topics by E-print Network

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

    made with either sodium chloride or potassium chloride. The addition of 75 or 150 porn N02 did not lower plate counts (P&0. 05... Kayfus, Timothy Jon 2012-06-07 39 Evaluation...

  19. aqueous sodium chloride: Topics by E-print Network

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

    made with either sodium chloride or potassium chloride. The addition of 75 or 150 porn N02 did not lower plate counts (P&0. 05... Kayfus, Timothy Jon 2012-06-07 58 Systematic...

  20. acidified sodium chlorite: Topics by E-print Network

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

    Summary: In order to improve a new design for a uranium startup sodium cooled fast reactor which was proposed at MIT, this thesis evaluated radial power flattening by varying...

  1. Loop simulation capability for sodium-cooled systems

    E-Print Network [OSTI]

    Adekugbe, Oluwole A.

    1984-01-01T23:59:59.000Z

    A one-dimensional loop simulation capability has been implemented in the thermal-hydraulic analysis code, THERMIT-4E. This code had been used to simulate and investigate flow in test sections of experimental sodium loops ...

  2. Probabilistic transient analysis of fuel choices for sodium fast reactors

    E-Print Network [OSTI]

    Denman, Matthew R

    2011-01-01T23:59:59.000Z

    This thesis presents the implications of using a risk-informed licensing framework to inform the design of Sodium Fast Reactors. NUREG-1860, more commonly known as the Technology Neutral Framework (TNF), is a risk-informed ...

  3. Reactor protection system design alternatives for sodium fast reactors

    E-Print Network [OSTI]

    DeWitte, Jacob D. (Jacob Dominic)

    2011-01-01T23:59:59.000Z

    Historically, unprotected transients have been viewed as design basis events that can significantly challenge sodium-cooled fast reactors. The perceived potential consequences of a severe unprotected transient in a ...

  4. A Photoelectron Spectroscopic and Computational Study of Sodium...

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

    The global minimum of Na3Au3 - has a bent-flake structure lying 0.077 eV below a more compact structure. The global minima of the sodium auride clusters are confirmed by the...

  5. SLAM: a sodium-limestone concrete ablation model

    SciTech Connect (OSTI)

    Suo-Anttila, A.J.

    1983-12-01T23:59:59.000Z

    SLAM is a three-region model, containing a pool (sodium and reaction debris) region, a dry (boundary layer and dehydrated concrete) region, and a wet (hydrated concrete) region. The model includes a solution to the mass, momentum, and energy equations in each region. A chemical kinetics model is included to provide heat sources due to chemical reactions between the sodium and the concrete. Both isolated model as well as integrated whole code evaluations have been made with good results. The chemical kinetics and water migration models were evaluated separately, with good results. Several small and large-scale sodium limestone concrete experiments were simulated with reasonable agreement between SLAM and the experimental results. The SLAM code was applied to investigate the effects of mixing, pool temperature, pool depth and fluidization. All these phenomena were found to be of significance in the predicted response of the sodium concrete interaction. Pool fluidization is predicted to be the most important variable in large scale interactions.

  6. Sodium bicarbonate and Alkaten as buffers in beef cattle diets

    E-Print Network [OSTI]

    Boerner, Benedict Joseph

    1985-01-01T23:59:59.000Z

    SODIUM BICARBONATE AND ALKATEN AS BUFFERS IN BEEF CATTLE DIETS A Thesis by BENED ICT JOSEP H BOERNER Submitted to the Graduate College of Texas A8M University im partial fulfillment of the requirements for the degree of MASTER OF SC IENCE... August 1985 Major Subject: Nutrition SODIUM BICARBONATE AND ALKATEN AS BUFFERS IN BEEF CATTLE DIETS A thesis by BENEDICT JOSEPH BOERNER Approved as to style and content by: Flo M. Byers (Chairma of Committee) ~r( Gerald T. Schelling (Member...

  7. The Salt or Sodium Chloride Content of Feeds

    E-Print Network [OSTI]

    Fraps, G. S. (George Stronach); Lomanitz, S. (Sebastian)

    1920-01-01T23:59:59.000Z

    1 EXAS AGRICULTURAL EXPERIMENT STATION AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS W. B. BIZZELL, Preeident BULLETIN NO. 271 OCTOBER, 1920 DIVISION OF CHEMISTRY THE SALT OR SODIUM CHLORIDE CONTENT OF FEEDS B. YOUNGBLOOD, DIRECTOK COLLEGE.... ............... Salt content of feecls.. ......... Salt content of mixed feeds.. ................... Summary ancl conclusions. Page. l1 [Blank Page in Original Bulletin] BULLETIN XO. 271. OCTOBE- '"On THE SALT OR SODIUM CHLORIDE CONTENT OF FEI The Texas feed...

  8. Classification : Original Article VOLTAGE-GATED SODIUM CHANNELS POTENTIATE THE INVASIVE

    E-Print Network [OSTI]

    Boyer, Edmond

    - gated sodium channels in non-small-cell lung cancer cell lines. Functional voltage-gated sodium channels cancerous cell lines H23, H460 and Calu-1 possess functional sodium channels while normal and weakly metastatic cell lines do not. While all the cell lines expressed mRNA for numerous sodium channel isoforms

  9. Advanced sodium fast reactor accident source terms : research needs.

    SciTech Connect (OSTI)

    Powers, Dana Auburn; Clement, Bernard [IRSN/DPAM.SEMIC Bt 702, Saint-Paul-lez-Durance, France; Denning, Richard [Ohio State University, Columbus, OH; Ohno, Shuji [Japan Atomic Energy Agency, Ibaraki, Japan; Zeyen, Roland [Institute for Energy Petten, Saint-Paul-lez-Durance, France

    2010-09-01T23:59:59.000Z

    An expert opinion elicitation has been used to evaluate phenomena that could affect releases of radionuclides during accidents at sodium-cooled fast reactors. The intent was to identify research needed to develop a mechanistic model of radionuclide release for licensing and risk assessment purposes. Experts from the USA, France, the European Union, and Japan identified phenomena that could affect the release of radionuclides under hypothesized accident conditions. They qualitatively evaluated the importance of these phenomena and the need for additional experimental research. The experts identified seven phenomena that are of high importance and have a high need for additional experimental research: High temperature release of radionuclides from fuel during an energetic eventEnergetic interactions between molten reactor fuel and sodium coolant and associated transfer of radionuclides from the fuel to the coolantEntrainment of fuel and sodium bond material during the depressurization of a fuel rod with breached claddingRates of radionuclide leaching from fuel by liquid sodiumSurface enrichment of sodium pools by dissolved and suspended radionuclidesThermal decomposition of sodium iodide in the containment atmosphereReactions of iodine species in the containment to form volatile organic iodides. Other issues of high importance were identified that might merit further research as development of the mechanistic model of radionuclide release progressed.

  10. Silica–silica Polyimide Buffered Optical Fibre Irradiation and Strength Experiment at Cryogenic Temperatures for 355 nm Pulsed Lasers

    E-Print Network [OSTI]

    Takala, E; Bordini, B; Bottura, L; Bremer, J; Rossi, L

    2012-01-01T23:59:59.000Z

    A controlled UV-light delivery system is envisioned to be built in order to study the stability properties of superconducting strands. The application requires a wave guide from room temperature to cryogenic temperatures. Hydrogen loaded and unloaded polyimide buffered silica–silica 100 microm core fibres were tested at cryogenic temperatures. A thermal stress test was done at 1.9 K and at 4.2 K which shows that the minimal mechanical bending radius for the fibre can be 10 mm for testing (transmission was not measured). The cryogenic transmission loss was measured for one fibre to assess the magnitude of the transmission decrease due to microbending that takes place during cooldown. UV-irradiation degradation measurements were done for bent fibres at 4.2 K with a deuterium lamp and 355 nm pulsed lasers. The irradiation tests show that the fibres have transmission degradation only for wavelengths smaller than 330 nm due to the two photon absorption. The test demonstrates that the fibres are suitable for the ...

  11. Apoptosis induction by silica nanoparticles mediated through reactive oxygen species in human liver cell line HepG2

    SciTech Connect (OSTI)

    Ahmad, Javed [Department of Zoology, College of Science, King Saud University, Riyadh 11451 (Saudi Arabia)] [Department of Zoology, College of Science, King Saud University, Riyadh 11451 (Saudi Arabia); Ahamed, Maqusood, E-mail: maqusood@gmail.com [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia)] [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Akhtar, Mohd Javed [Fibre Toxicology, CSIR-Indian Institute of Toxicology Research, Lucknow-226001 (India)] [Fibre Toxicology, CSIR-Indian Institute of Toxicology Research, Lucknow-226001 (India); Alrokayan, Salman A. [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia)] [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh 11451 (Saudi Arabia); Siddiqui, Maqsood A.; Musarrat, Javed; Al-Khedhairy, Abdulaziz A. [Department of Zoology, College of Science, King Saud University, Riyadh 11451 (Saudi Arabia)] [Department of Zoology, College of Science, King Saud University, Riyadh 11451 (Saudi Arabia)

    2012-03-01T23:59:59.000Z

    Silica nanoparticles are increasingly utilized in various applications including agriculture and medicine. In vivo studies have shown that liver is one of the primary target organ of silica nanoparticles. However, possible mechanisms of hepatotoxicity caused by silica nanoparticles still remain unclear. In this study, we explored the reactive oxygen species (ROS) mediated apoptosis induced by well-characterized 14 nm silica nanoparticles in human liver cell line HepG2. Silica nanoparticles (25–200 ?g/ml) induced a dose-dependent cytotoxicity in HepG2 cells. Silica nanoparticles were also found to induce oxidative stress in dose-dependent manner indicated by induction of ROS and lipid peroxidation and depletion of glutathione (GSH). Quantitative real-time PCR and immunoblotting results showed that both the mRNA and protein expressions of cell cycle checkpoint gene p53 and apoptotic genes (bax and caspase-3) were up-regulated while the anti-apoptotic gene bcl-2 was down-regulated in silica nanoparticles treated cells. Moreover, co-treatment of ROS scavenger vitamin C significantly attenuated the modulation of apoptotic markers along with the preservation of cell viability caused by silica nanoparticles. Our data demonstrated that silica nanoparticles induced apoptosis in human liver cells, which is ROS mediated and regulated through p53, bax/bcl-2 and caspase pathways. This study suggests that toxicity mechanisms of silica nanoparticles should be further investigated at in vivo level. -- Highlights: ? We explored the mechanisms of toxicity caused by silica NPs in human liver HepG2 cells. ? Silica NPs induced a dose-dependent cytotoxicity in HepG2 cells. ? Silica NPs induced ROS generation and oxidative stress in a dose-dependent manner. ? Silica NPs were also modulated apoptosis markers both at mRNA and protein levels. ? ROS mediated apoptosis induced by silica NPs was preserved by vitamin C.

  12. publication 348-827 Sodium is a necessary part of our diet. Sodium helps our bodies keep the right

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    amount of water, but we only need a little bit. The most common form of sodium is found in table salt-fashioned oatmeal Pasta and rice Peas, beans, and lentils Plain popcorn Pudding Seeds Unsalted nuts Whole

  13. INFLUENCE OF PHENYLTRIMETHOXYSILANE ON PHYSICOCHEMICAL PROPERTIES OF TEOS BASED MONOLITHIC SILICA AEROGELS PREPARED BY SUPERCRITICAL DRYING PROCESS

    E-Print Network [OSTI]

    Kavale Mahendra S; Mahadik D. B; Parale V. G; Mane P. B; Vhatkar R. S; A. Venkateswara Rao; Wagh P. B; Satish C. Gupta

    The objective of the present research work is to synthesize transparent, hydrophobic, monolithic silica aerogels with ultralow density by using supercritical drying process. The effect of phenyltrimethoxysilane as a hydrophobic reagent on the physicochemical properties of the silica aerogels has been studied. The total processing time for the synthesis of monolithic silica aerogels minimized to 29 h which was ~2 days. We have succeeded to get ultralow density of the silica aerogels as low as 24 Kgm-3 with 165 ° water droplet contact angle. The ultralow density affects the thermal conductivity of the silica aerogels.

  14. Mesoporous silica nanoparticles for biomedical and catalytical applications

    SciTech Connect (OSTI)

    Sun, Xiaoxing

    2011-05-15T23:59:59.000Z

    Mesoporous silica materials, discovered in 1992 by the Mobile Oil Corporation, have received considerable attention in the chemical industry due to their superior textual properties such as high surface area, large pore volume, tunable pore diameter, and narrow pore size distribution. Among those materials, MCM-41, referred to Mobile Composition of Matter NO. 41, contains honeycomb liked porous structure that is the most common mesoporous molecular sieve studied. Applications of MCM-41 type mesoporous silica material in biomedical field as well as catalytical field have been developed and discussed in this thesis. The unique features of mesoporous silica nanoparticles were utilized for the design of delivery system for multiple biomolecules as described in chapter 2. We loaded luciferin into the hexagonal channels of MSN and capped the pore ends with gold nanoparticles to prevent premature release. Luciferase was adsorbed onto the outer surface of the MSN. Both the MSN and the gold nanoparticles were protected by poly-ethylene glycol to minimize nonspecific interaction of luciferase and keep it from denaturating. Controlled release of luciferin was triggered within the cells and the enzymatic reaction was detected by a luminometer. Further developments by varying enzyme/substrate pairs may provide opportunities to control cell behavior and manipulate intracellular reactions. MSN was also served as a noble metal catalyst support due to its large surface area and its stability with active metals. We prepared MSN with pore diameter of 10 nm (LP10-MSN) which can facilitate mass transfer. And we successfully synthesized an organo silane, 2,2'-Bipyridine-amide-triethoxylsilane (Bpy-amide-TES). Then we were able to functionalize LP10-MSN with bipyridinyl group by both post-grafting method and co-condensation method. Future research of this material would be platinum complexation. This Pt (II) complex catalyst has been reported for a C-H bond activation reaction as an alternative of the traditional Friedel-Crafts reaction. And we will compare the turnover numbers of MSN supported material with homogenous catalyst to evaluate the catalytical efficiency of our material.

  15. Amorphous silica in ultra-high performance concrete: First hour of hydration

    SciTech Connect (OSTI)

    Oertel, Tina, E-mail: tina.oertel@isc.fraunhofer.de [Fraunhofer-Institute for Silicate Research ISC, Neunerplatz 2, 97082 Würzburg (Germany); Chair for Inorganic Chemistry I, Universität Bayreuth, Universitätsstr. 30, 95440 Bayreuth (Germany); Hutter, Frank [Fraunhofer-Institute for Silicate Research ISC, Neunerplatz 2, 97082 Würzburg (Germany); Helbig, Uta, E-mail: uta.helbig@th-nuernberg.de [Chair for Crystallography and X-ray Methods, Technische Hochschule Nürnberg Georg Simon Ohm, Wassertorstraße 10, 90489 Nürnberg (Germany); Sextl, Gerhard [Fraunhofer-Institute for Silicate Research ISC, Neunerplatz 2, 97082 Würzburg (Germany); Chair for Chemical Technology of Advanced Materials, Julius Maximilian Universität, Röntgenring 11, 97070 Würzburg (Germany)

    2014-04-01T23:59:59.000Z

    Amorphous silica in the sub-micrometer size range is widely used to accelerate cement hydration. Investigations including properties of silica which differ from the specific surface area are rare. In this study, the reactivity of varying types of silica was evaluated based on their specific surface area, surface silanol group density, content of silanol groups and solubility in an alkaline suspension. Pyrogenic silica, silica fume and silica synthesized by hydrolysis and condensation of alkoxy silanes, so-called Stoeber particles, were employed. Influences of the silica within the first hour were further examined in pastes with water/cement ratios of 0.23 using in-situ X-ray diffraction, cryo scanning electron microscopy and pore solution analysis. It was shown that Stoeber particles change the composition of the pore solution. Na{sup +}, K{sup +}, Ca{sup 2+} and silicate ions seem to react to oligomers. The extent of this reaction might be highest for Stoeber particles due to their high reactivity.

  16. Encapsulated in silica: genome, proteome and physiology of the thermophilic bacterium Anoxybacillus flavithermus

    SciTech Connect (OSTI)

    Saw, Jimmy H [Los Alamos National Laboratory; Mountain, Bruce W [NEW ZEALAND; Feng, Lu [NANKAI UNIV; Omelchenko, Marina V [NCBI/NLM/NIH; Hou, Shaobin [UNIV OF HAWAII; Saito, Jennifer A [UNIV OF HAWAII; Stott, Matthew B [NEW ZEALAND; Li, Dan [NANKAI UNIV; Zhao, Guang [NANKAI UNIV; Wu, Junli [NANKAI UNIV; Galperin, Michael Y [NCBI/NLM/NIH; Koonin, Eugene V [NCBI/NLM/NIH; Makarova, Kira S [NCBI/NLM/NIH; Wolf, Yuri I [NCBI/NLM/NIH; Rigden, Daniel J [UNIV OF LIVERPOOL; Dunfield, Peter F [UNIV OF CALGARY; Wang, Lei [NANKAI UNIV; Alam, Maqsudul [UNIV OF HAWAII

    2008-01-01T23:59:59.000Z

    Gram-positive bacteria of the genus Anoxybacillus have been found in diverse thermophilic habitats, such as geothermal hot springs and manure, and in processed foods such as gelatin and milk powder. Anoxybacillus flavithermus is a facultatively anaerobic bacterium found in super-saturated silica solutions and in opaline silica sinter. The ability of A. flavithermus to grow in super-saturated silica solutions makes it an ideal subject to study the processes of sinter formation, which might be similar to the biomineralization processes that occurred at the dawn of life. We report here the complete genome sequence of A. flavithermus strain WK1, isolated from the waste water drain at the Wairakei geothermal power station in New Zealand. It consists of a single chromosome of 2,846,746 base pairs and is predicted to encode 2,863 proteins. In silico genome analysis identified several enzymes that could be involved in silica adaptation and biofilm formation, and their predicted functions were experimentally validated in vitro. Proteomic analysis confirmed the regulation of biofilm-related proteins and crucial enzymes for the synthesis of long-chain polyamines as constituents of silica nanospheres. Microbial fossils preserved in silica and silica sinters are excellent objects for studying ancient life, a new paleobiological frontier. An integrated analysis of the A. flavithermus genome and proteome provides the first glimpse of metabolic adaptation during silicification and sinter formation. Comparative genome analysis suggests an extensive gene loss in the Anoxybacillus/Geobacillus branch after its divergence from other bacilli.

  17. Mechanical Loss in Tantala/Silica Dielectric Mirror Coatings

    E-Print Network [OSTI]

    Steven D. Penn; Peter H. Sneddon; Helena Armandula; Joseph C. Betzwieser; Gianpietro Cagnoli; Jordan Camp; D. R. M. Crooks; Martin M. Fejer; Andri M. Gretarsson; Gregory M. Harry; Jim Hough; Scott E. Kittelberger; Michael J. Mortonson; Roger Route; Sheila Rowan; Christophoros C. Vassiliou

    2003-02-24T23:59:59.000Z

    Current interferometric gravitational wave detectors use test masses with mirror coatings formed from multiple layers of dielectric materials, most commonly alternating layers of SiO2 (silica) and Ta2O5 (tantala). However, mechanical loss in the Ta2O5/SiO2 coatings may limit the design sensitivity for advanced detectors. We have investigated sources of mechanical loss in the Ta2O5/SiO2 coatings, including loss associated with the coating-substrate interface, with the coating-layer interfaces, and with the bulk material. Our results indicate that the loss is associated with the bulk coating materials and that the loss of Ta2O5 is substantially larger than that of SiO2.

  18. Synthesis and characterization of barium ferrite–silica nanocomposites

    SciTech Connect (OSTI)

    Aguilar-González, M.A.; Mendoza-Suárez, G.; Padmasree, K.P., E-mail: padma512@yahoo.com

    2013-10-15T23:59:59.000Z

    In this work, we prepared barium ferrite-silica (BaM-SiO{sub 2}) nanocomposites of different molar ratios by high-energy ball milling, followed by heat-treatment at different temperatures. The microstructure, morphology and magnetic properties were characterized for different synthesis conditions by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometry (VSM). The results indicate that 15 h of milling was enough to avoid the generation of hematite phase and to get a good dispersion of barium ferrite particles in the ceramic matrix. For milling periods beyond 15 h and heat treatment above 900 °C, the XRD patterns showed the presence of hematite phase caused by the decomposition of BaM. The agglomerate size observed through SEM analysis was around 150 nm with a good BaM dispersion into the SiO{sub 2} matrix. The highest saturation magnetization (Ms) value obtained was 43 emu/g and the corresponding coercivity (Hc) value of 3.4 kOe for the composition 60BaM-40SiO{sub 2} milled for 15 h and heat treated at 900 °C. This coercivity value is acceptable for the application in magnetic recording media. Highlights: • Barium ferrite–silica nanocomposites were prepared by high energy ball milling. • Optimal processing time is 15 h milling and heat treatment at 900 °C. • This is enough to avoid the generation of hematite phase. • Obtain good dispersion of barium ferrite particles in the ceramic matrix • Above this processing time shows the presence of increased amount of hematite.

  19. Studies of Immobilized Homogeneous Metal Catalysts on Silica Supports

    SciTech Connect (OSTI)

    Keith James Stanger

    2003-05-31T23:59:59.000Z

    The tethered, chiral, chelating diphosphine rhodium complex, which catalyzes the enantioselective hydrogenation of methyl-{alpha}-acetamidocinnamate (MAC), has the illustrated structure as established by {sup 31}P NMR and IR studies. Spectral and catalytic investigations also suggest that the mechanism of action of the tethered complex is the same as that of the untethered complex in solution. The rhodium complexes, [Rh(COD)H]{sub 4}, [Rh(COD){sub 2}]{sup +}BF{sub 4}{sup -}, [Rh(COD)Cl]{sub 2}, and RhCl{sub 3} {center_dot} 3H{sub 2}O, adsorbed on SiO{sub 2} are optimally activated for toluene hydrogenation by pretreatment with H{sub 2} at 200 C. The same complexes on Pd-SiO{sub 2} are equally active without pretreatments. The active species in all cases is rhodium metal. The catalysts were characterized by XPS, TEM, DRIFTS, and mercury poisoning experiments. Rhodium on silica catalyzes the hydrogenation of fluorobenzene to produce predominantly fluorocyclohexane in heptane and 1,2-dichloroethane solvents. In heptane/methanol and heptane/water solvents, hydrodefluorination to benzene and subsequent hydrogenation to cyclohexane occurs exclusively. Benzene inhibits the hydrodefluorination of fluorobenzene. In DCE or heptane solvents, fluorocyclohexane reacts with hydrogen fluoride to form cyclohexene. Reaction conditions can be chosen to selectively yield fluorocyclohexane, cyclohexene, benzene, or cyclohexane. The oxorhenium(V) dithiolate catalyst [-S(CH{sub 2}){sub 3}s-]Re(O)(Me)(PPh{sub 3}) was modified by linking it to a tether that could be attached to a silica support. Spectroscopic investigation and catalytic oxidation reactivity showed the heterogenized catalyst's structure and reactivity to be similar to its homogeneous analog. However, the immobilized catalyst offered additional advantages of recyclability, extended stability, and increased resistance to deactivation.

  20. KrF- and ArF-excimer-laser-induced absorption in silica glasses produced by melting synthetic silica powder

    SciTech Connect (OSTI)

    Kuzuu, Nobu; Sasaki, Toshiya; Kojima, Tatsuya [Department of Applied Physics, University of Fukui, 3-9-1 Bunkyo, Fukui-shi, Fukui 910-8507 (Japan); Tanaka, Jun-ichiro; Nakamura, Takayuki; Horikoshi, Hideharu [Tosoh SGM Corp., 4555 Kaisei-cho, Shunan-shi, Yamaguchi 746-0006 (Japan)

    2013-07-07T23:59:59.000Z

    KrF- and ArF-excimer-laser-induced absorption of silica glasses produced by electric melting and flame fusion of synthetic silica powder were investigated. The growth of KrF-laser-induced absorption was more gradual than that of ArF-laser-induced absorption. Induced absorption spectra exhibited a peak at about 5.8 eV, of which the position and width differed slightly among samples and laser species. Widths of ArF-laser-induced absorption spectra were wider than those of KrF-laser-induced spectra. KrF-laser-induced absorption is reproducible by two Gaussian absorption bands peaking at 5.80 eV with full width at half maximum (FWHM) of 0.62 eV and at 6.50 eV with FWHM of 0.74 eV. For reproduction of ArF-laser-induced absorption, Gaussian bands at 5.41 eV with FWHM of 0.62 eV was necessary in addition to components used for reproducing KrF-laser-induced absorption. Based on the discussion of the change of defect structures evaluated from change of absorption components, we proposed that the precursor of the 5.8-eV band ascribed to E Prime center ({identical_to}Si{center_dot}) is {identical_to}Si-H HO-Si{identical_to} structures formed by the reaction between strained Si-O-Si bonds and interstitial H{sub 2} molecules during the irradiation.

  1. ORNL devises recipe to fine-tune diameter of silica rods | ornl...

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

    the stage for advances in anti-reflective solar cells, computer monitors, TV screens, eye glasses and more. The goal of fabricating fixed-size one-dimensional silica structures...

  2. Method for inhibiting silica precipitation and scaling in geothermal flow systems

    DOE Patents [OSTI]

    Harrar, J.E.; Lorensen, L.E.; Locke, F.E.

    1980-06-13T23:59:59.000Z

    A method for inhibiting silica scaling and precipitation in geothermal flow systems by on-line injection of low concentrations of cationic nitrogen-containing compounds, particularly polymeric imines, polymeric amines, and quaternary ammonium compounds is described.

  3. Method for inhibiting silica precipitation and scaling in geothermal flow systems

    DOE Patents [OSTI]

    Harrar, Jackson E. (Castro Valley, CA); Lorensen, Lyman E. (Orinda, CA); Locke, Frank E. (Lafayette, CA)

    1982-01-01T23:59:59.000Z

    A method for inhibiting silica scaling and precipitation in geothermal flow systems by on-line injection of low concentrations of cationic nitrogen-containing compounds, particularly polymeric imines, polymeric amines, and quaternary ammonium compounds.

  4. Study of the Behavior of a Commercial Scale Inhibitor on Silica Sand

    E-Print Network [OSTI]

    Vaca Bustamante, Victor

    2010-12-14T23:59:59.000Z

    squeeze lifetimes in order to minimize the number of treatments, thus reducing the cost. The objective of this thesis is to study the adsorption of the commercial scale inhibitor SI onto silica sand. By investigating this intrinsic phenomenon, an optimized...

  5. Silica stabilized iron particles toward anti-corrosion magnetic polyurethane nanocomposites

    E-Print Network [OSTI]

    Guo, John Zhanhu

    Silica stabilized iron particles toward anti-corrosion magnetic polyurethane nanocomposites Jiahua with various materials to form core-shell structures results in the new hybrid materials, which can be used

  6. Laser-induced fluorescence of fused silica irradiated by ArF excimer laser

    SciTech Connect (OSTI)

    Zhang Haibo [Shanghai Key Laboratory of All Solid-state Laser and Applied Techniques, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, Shanghai 201800 (China); Graduate University of Chinese Academy of Science, Beijing 100049 (China); Yuan Zhijun; Zhou Jun; Dong Jingxing; Wei Yunrong; Lou Qihong [Shanghai Key Laboratory of All Solid-state Laser and Applied Techniques, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, Shanghai 201800 (China)

    2011-07-01T23:59:59.000Z

    Laser-induced fluorescence (LIF) of high-purity fused silica irradiated by ArF excimer laser is studied experimentally. LIF bands of the fused silica centered at 281 nm, 478 nm, and 650 nm are observed simultaneously. Furthermore, the angular distribution of the three fluorescence peaks is examined. Microscopic image of the laser modified fused silica indicates that scattering of the generated fluorescence by laser-induced damage sites is the main reason for the angular distribution of LIF signals. Finally, the dependence of LIF signals intensities of the fused silica on laser power densities is presented. LIF signals show a squared power density dependence, which indicates that laser-induced defects are formed mainly via two-photon absorption processes.

  7. Treatment of domestic wastewater for reuse with activated silica and magnesia

    E-Print Network [OSTI]

    Lindner, John Howard

    1985-01-01T23:59:59.000Z

    which are of concern in treat- ment for potable purposes are organics and trace inorganics. This research project was conducted in an attempt to determine if organic oxides such as activated silica and magnesia in various combinations with alum... in Wastewater Toxic Inorganics in Wastewater Existing Technology Coagulation and Flocculation Lime Coagulation . . ~ Alum Coagulation . ~ ~ ~ ~ Activated Silica Magnesia 5 6 8 9 10 13 14 15 16 III EXPERIMENTAL PLAN Was tewater ~ ~ ~ ~ ~ Jar...

  8. Luminescent studies of fluorescent chromophore-doped silica aerogels for flat panel display applications

    SciTech Connect (OSTI)

    Glauser, S.A.C. [California Univ., Davis, CA (United States). Dept. of Applied Science; Lee, H.W.H. [Lawrence Livermore National Lab., CA (United States)

    1997-04-01T23:59:59.000Z

    The remarkable optical and electronic properties of doped and undoped silica aerogels establish their utility as unique, mulitfunctional host materials for fluorescent dyes and other luminescent materials for display and imaging applications. We present results on the photoluminescence, absorption, and photoluminescence excitation spectra of undoped silica aerogels and aerogels doped with Er{sup 3+}, rhodamine 6G (R6G), and fluorescein. 4 refs., 12 figs.

  9. Sidestream treatment of high silica cooling water and reverse osmosis desalination in geothermal power generation

    SciTech Connect (OSTI)

    Mindler, A.B.; Bateman, S.T.

    1981-01-19T23:59:59.000Z

    Bench scale and pilot plant test work has been performed on cooling water for silica reduction and water reuse, at DOE's Raft River Geothermal Site, Malta, Idaho in cooperation with EG and G (Idaho), Inc. Technical supervision was by Permutit. A novel process of rusting iron shavings was found effective and economical in reducing silica to less than 20 mg/l. Reverse Osmosis was investigated for water reuse after pretreatment and ion exchange softening.

  10. Aluminum Zintl anion moieties within sodium aluminum clusters

    SciTech Connect (OSTI)

    Wang, Haopeng; Zhang, Xinxing; Ko, Yeon Jae; Grubisic, Andrej; Li, Xiang; Ganteför, Gerd; Bowen, Kit H., E-mail: AKandalam@wcupa.edu, E-mail: kiran@mcneese.edu, E-mail: kbowen@jhu.edu [Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Schnöckel, Hansgeorg [Institute of Inorganic Chemistry, Karlsruhe Institute of Technology, 76128 Karlsruhe (Germany)] [Institute of Inorganic Chemistry, Karlsruhe Institute of Technology, 76128 Karlsruhe (Germany); Eichhorn, Bryan W. [Department of Chemistry, University of Maryland at College Park, College Park, Maryland 20742 (United States)] [Department of Chemistry, University of Maryland at College Park, College Park, Maryland 20742 (United States); Lee, Mal-Soon; Jena, P. [Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284 (United States)] [Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284 (United States); Kandalam, Anil K., E-mail: AKandalam@wcupa.edu, E-mail: kiran@mcneese.edu, E-mail: kbowen@jhu.edu [Department of Physics, West Chester University of Pennsylvania, West Chester, Pennsylvania 19383 (United States); Kiran, Boggavarapu, E-mail: AKandalam@wcupa.edu, E-mail: kiran@mcneese.edu, E-mail: kbowen@jhu.edu [Department of Chemistry, McNeese State University, Lake Charles, Louisiana 70609 (United States)] [Department of Chemistry, McNeese State University, Lake Charles, Louisiana 70609 (United States)

    2014-02-07T23:59:59.000Z

    Through a synergetic combination of anion photoelectron spectroscopy and density functional theory based calculations, we have established that aluminum moieties within selected sodium-aluminum clusters are Zintl anions. Sodium–aluminum cluster anions, Na{sub m}Al{sub n}{sup ?}, were generated in a pulsed arc discharge source. After mass selection, their photoelectron spectra were measured by a magnetic bottle, electron energy analyzer. Calculations on a select sub-set of stoichiometries provided geometric structures and full charge analyses for both cluster anions and their neutral cluster counterparts, as well as photodetachment transition energies (stick spectra), and fragment molecular orbital based correlation diagrams.

  11. The magnesium nutrition of cotton as influenced by sodium 

    E-Print Network [OSTI]

    Thenabadu, Mervyn Wellesly

    1964-01-01T23:59:59.000Z

    1964 Major Subject. Plant Physic logy THE MAGNESIUM NUTRITION OF COTTON AS INFLUENCED BY SODIUM A Thesis By MERVYN M. THENABADU Approved as to style and content by: Chairman of Commi. e Nun Head of Department Member Mem, er Member Member... REVIEW OF LITERATURE (a) Sodium as a plant nutrient (b) I'he role of magnesium in plant nutrition MATERIALS AND METHODS RESUL:S DISCUSSION 13 21 24 (a) The effect of treatments on grcwth and reproduction (b) The effect of treatments on the ccr...

  12. Implantation conditions for diamond nanocrystal formation in amorphous silica

    SciTech Connect (OSTI)

    Buljan, Maja; Radovic, Iva Bogdanovic; Desnica, Uros V.; Ivanda, Mile; Jaksic, Milko [Ruder Boskovic Institute, P.O. Box 180, 10002 Zagreb (Croatia); Saguy, Cecile; Kalish, Rafi [Physics Department and Solid State Institute, Technion, Haifa 32000 (Israel); Djerdj, Igor [Department of Materials, Swiss Federal Institute of Technology (ETH) Zuerich, Wolfgang-Pauli-Str. 10, CH-8093 Zuerich (Switzerland); Tonejc, Andelka [Faculty of Science, Department of Physics, University of Zagreb, 10000 Zagreb (Croatia); Gamulin, Ozren [School of Medicine, Zagreb University, 10000 Zagreb (Croatia)

    2008-08-01T23:59:59.000Z

    We present a study of carbon ion implantation in amorphous silica, which, followed by annealing in a hydrogen-rich environment, leads to preferential formation of carbon nanocrystals with cubic diamond (c-diamond), face-centered cubic (n-diamond), or simple cubic (i-carbon) carbon crystal lattices. Two different annealing treatments were used: furnace annealing for 1 h and rapid thermal annealing for a brief period, which enables monitoring of early nucleation events. The influence of implanted dose and annealing type on carbon and hydrogen concentrations, clustering, and bonding were investigated. Rutherford backscattering, elastic recoil detection analysis, infrared spectroscopy, transmission electron microscopy, selected area electron diffraction, ultraviolet-visible absorption measurements, and Raman spectroscopy were used to study these carbon formations. These results, combined with the results of previous investigations on similar systems, show that preferential formation of different carbon phases (diamond, n-diamond, or i-carbon) depends on implantation energy, implantation dose, and annealing conditions. Diamond nanocrystals formed at a relatively low carbon volume density are achieved by deeper implantation and/or lower implanted dose. Higher volume densities led to n-diamond and finally to i-carbon crystal formation. This observed behavior is related to damage sites induced by implantation. The optical properties of different carbon nanocrystal phases were significantly different.

  13. Templated Control of Au nanospheres in Silica Nanowires

    SciTech Connect (OSTI)

    Tringe, J W; Vanamu, G; Zaidi, S H

    2007-03-15T23:59:59.000Z

    The formation of regularly-spaced metal nanostructures in selectively-placed insulating nanowires is an important step toward realization of a wide range of nano-scale electronic and opto-electronic devices. Here we report templated synthesis of Au nanospheres embedded in silica nanowires, with nanospheres consistently spaced with a period equal to three times their diameter. Under appropriate conditions, nanowires form exclusively on Si nanostructures because of enhanced local oxidation and reduced melting temperatures relative to templates with larger dimensions. We explain the spacing of the nanospheres with a general model based on a vapor-liquid-solid mechanism, in which an Au/Si alloy dendrite remains liquid in the nanotube until a critical Si concentration is achieved locally by silicon oxide-generated nanowire growth. Additional Si oxidation then locally reduces the surface energy of the Au-rich alloy by creating a new surface with minimum area inside of the nanotube. The isolated liquid domain subsequently evolves to become an Au nanosphere, and the process is repeated.

  14. Method of Manufacturing Micro-Disperse Particles of Sodium Borohydride

    DOE Patents [OSTI]

    Kravitz, Stanley H. (Placitas, NM); Hecht, Andrew M. (Sandia Park, NM); Sylwester. Alan P. (Albuquerque, NM); Bell, Nelson S. (Albuquerque, NM)

    2008-09-23T23:59:59.000Z

    A compact solid source of hydrogen gas, where the gas is generated by contacting water with micro-disperse particles of sodium borohydride in the presence of a catalyst, such as cobalt or ruthenium. The micro-disperse particles can have a substantially uniform diameter of 1-10 microns, and preferably about 3-5 microns. Ruthenium or cobalt catalytic nanoparticles can be incorporated in the micro-disperse particles of sodium borohydride, which allows a rapid and complete reaction to occur without the problems associated with caking and scaling of the surface by the reactant product sodium metaborate. A closed loop water management system can be used to recycle wastewater from a PEM fuel cell to supply water for reacting with the micro-disperse particles of sodium borohydride in a compact hydrogen gas generator. Capillary forces can wick water from a water reservoir into a packed bed of micro-disperse fuel particles, eliminating the need for using an active pump.

  15. Method of generating hydrogen gas from sodium borohydride

    DOE Patents [OSTI]

    Kravitz, Stanley H. (Placitas, NM); Hecht, Andrew M. (Sandia Park, NM); Sylwester, Alan P. (Albuquerque, NM); Bell, Nelson S. (Albuquerque, NM)

    2007-12-11T23:59:59.000Z

    A compact solid source of hydrogen gas, where the gas is generated by contacting water with micro-disperse particles of sodium borohydride in the presence of a catalyst, such as cobalt or ruthenium. The micro-disperse particles can have a substantially uniform diameter of 1-10 microns, and preferably about 3-5 microns. Ruthenium or cobalt catalytic nanoparticles can be incorporated in the micro-disperse particles of sodium borohydride, which allows a rapid and complete reaction to occur without the problems associated with caking and scaling of the surface by the reactant product sodium metaborate. A closed loop water management system can be used to recycle wastewater from a PEM fuel cell to supply water for reacting with the micro-disperse particles of sodium borohydride in a compact hydrogen gas generator. Capillary forces can wick water from a water reservoir into a packed bed of micro-disperse fuel particles, eliminating the need for using an active pump.

  16. ORIGINAL RESEARCH Systematic family-wide analysis of sodium bicarbonate

    E-Print Network [OSTI]

    Hall, Randy A

    ORIGINAL RESEARCH Systematic family-wide analysis of sodium bicarbonate cotransporter NBCn1/SLC4A7/NBCn1 pulled down syntrophin c2 and con- versely GST/syntrophin c2 pulled down NBCn1. Moreover normally moves Na+ and HCO3 Ã? into cells and protects intracel- lular pH (pHi) from falling below normal

  17. Immobilization of sodium nitrate waste with polymers: Topical report

    SciTech Connect (OSTI)

    Franz, E.M.; Heiser, J.H. III; Colombo, P.

    1987-04-01T23:59:59.000Z

    This report describes the development of solidification systems for sodium nitrate waste. Sodium nitrate waste was solidified in the polymers polyethylene, polyester-styrene (PES), and water-extendible polyester-styrene (WEP). Evaluations were made of the properties of waste forms containing various amounts of sodium nitrate by leaching immersion in water, measuring compressive strengths and by the EPA Extraction Procedure. Results of the leaching test are presented as cumulative fraction leached (CFL), incremental leaching rate, and average leaching indices (LI). For waste forms containing 30 to 70 wt% sodium nitrate, the CFL ranged from 9.0 x 10/sup -3/ to 7.3 x 10/sup -1/ and the LI from 11 to 7.8. After ninety days immersion in water, the compressive strengths ranged from 720 psi to 2550 psi. The nitrate releases from these samples using the EPA Extraction Procedure were below 500 ppM. The nitrate releases from PES waste forms were similar to those from polyethylene waste forms at the same waste loadings. The compressive yield strengths, measured after ninety-day immersion in water, ranged between 2070 and 7710 psi. In the case of WEP waste forms, only 30 wt% loaded samples passed the immersion test. 23 refs., 24 figs., 12 tabs.

  18. Electrochemical Recovery of Sodium Hydroxide from Alkaline Salt Solution

    SciTech Connect (OSTI)

    Hobbs, D.T. [Westinghouse Savannah River Company, AIKEN, SC (United States); Edwards, T.B.

    1996-10-01T23:59:59.000Z

    A statistically designed set of tests determined the effects of current density, temperature, and the concentrations of nitrate/nitrite, hydroxide and aluminate on the recovery of sodium as sodium hydroxide (caustic) from solutions simulating those produced from the Savannah River Site (SRS) In-Tank Precipitation process. These tests included low nitrate and nitrite concentrations which would be produced by electrolytic nitrate/nitrite destruction. The tests used a two compartment electrochemical cell with a Nafion Type 324 ion-exchange membrane. Caustic was successfully recovered from the waste solutions. Evaluation of the testing results indicated that the transport of sodium across the membrane was not significantly affected by any of the varied parameters. The observed variance in the sodium flux is attributed to experimental errors and variations in the performance characteristics of individual pieces of the organic-based Nafion membrane.Additional testing is recommended to determine the maximum current density, to evaluate the chemical durability of the organic membrane as a function of current density and to compare the durability and performance characteristics of the organic-based Nafion membrane with that of other commercially available organic membranes and the inorganic class of membranes under development by Ceramatec and PNNL.

  19. Compatibility Assessment of Advanced Stainless Steels in Sodium

    SciTech Connect (OSTI)

    Pawel, Steven J [ORNL

    2012-01-01T23:59:59.000Z

    Type 316L stainless steel capsules containing commercially pure sodium and miniature tensile specimens of HT-UPS (austenitic, 14Cr-16Ni), NF-616 (ferritic/martensitic, 9Cr-2W-0.5Mo), or 316L (austenitic, 17Cr-10Ni-2Mo) stainless steel were exposed at 600 or 700 C for 100 and 400 h as a screening test for compatibility. Using weight change, tensile testing, and metallographic analysis, HT-UPS and 316L were found to be largely immune to changes resulting from sodium exposure, but NF-616 was found susceptible to substantial decarburization at 700 C. Subsequently, two thermal convection loops (TCLs) constructed of 316L and loaded with commercially pure sodium and miniature tensile specimens of HT-UPS and 316L were operated for 2000 h each one between 500 and 650 C, the other between 565 and 725 C at a flow rate of about 1.5 cm/s. Changes in specimen appearance, weight, and tensile properties were observed to be very minor in all cases, and there was no metallographic evidence of microstructure changes, composition gradients, or mass transfer resulting from prolonged exposure in a TCL. Thus, it appears that HT-UPS and 316L stainless steels are similarly compatible with commercially pure sodium under these exposure conditions.

  20. Gypsum and Polyacrylamide Soil Amendments Used With High Sodium Wastewater

    E-Print Network [OSTI]

    Gardiner, Duane

    and sodium. Two soil amendments were applied to plots furrowirrigated with wastewater. The amendments were gypsum (11 Mg ha-1), and PAM added to irrigation water at rates of 25 mg L-1 PAM applications were made during every irrigation and during every second...

  1. Laboratory-scale sodium-carbonate aggregate concrete interactions. [LMFBR

    SciTech Connect (OSTI)

    Westrich, H.R.; Stockman, H.W.; Suo-Anttila, A.

    1983-09-01T23:59:59.000Z

    A series of laboratory-scale experiments was made at 600/sup 0/C to identify the important heat-producing chemical reactions between sodium and carbonate aggregate concretes. Reactions between sodium and carbonate aggregate were found to be responsible for the bulk of heat production in sodium-concrete tests. Exothermic reactions were initiated at 580+-30/sup 0/C for limestone and dolostone aggregates as well as for hydrated limestone concrete, and at 540+-10/sup 0/C for dehydrated limestone concrete, but were ill-defined for dolostone concrete. Major reaction products included CaO, MgO, Na/sub 2/CO/sub 3/, Na/sub 2/O, NaOH, and elemental carbon. Sodium hydroxide, which forms when water is released from cement phases, causes slow erosion of the concrete with little heat production. The time-temperature profiles of these experiments have been modeled with a simplified version of the SLAM computer code, which has allowed derivation of chemical reaction rate coefficients.

  2. Agrin regulation of alpha3 sodium-potassium ATPase activity modulates cardiac myocyte contraction.

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    in the U.S.A. Agrin Regulation of ? 3 Sodium-Potassiumis modulated by agrin regulation of ? 3 Na,K-ATPasegated sodium channels, capa- regulation of cardiac myocyte

  3. apical sodium-chloride cotransporter: Topics by E-print Network

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

    g magnesium chloride, 3.24 g magnesium sulfate bromide, 34 mg strontium chloride, 22 mg boric acid, 4 mg sodium silicate, 2.4 mg sodium fluoride, 1.6 mg Bae, Jin-Woo 302 The...

  4. Self-assembled laminated nanoribbon-directed synthesis of noble metallic nanoparticle-decorated silica nanotubes and their catalytic applications

    E-Print Network [OSTI]

    Huang, Jianbin

    such as silica dioxide (SiO2), titanium dioxide (TiO2), carbon nanotube (CNT), graphene, microgel, and polymer.18

  5. Poly(methylmethacrylate) adsorption onto flat substrates of glass and silica: Influence of water traces in solvent

    SciTech Connect (OSTI)

    Berquier, J. [Laboratoire CNRS-Saint-Gobain (UMR 125) 39, Quai Lucien Lefranc, F-93303 Aubervilliers Cedex

    1996-01-01T23:59:59.000Z

    The adsorbed amount of PMMA on flat glass and silica is measured by infrared external reflection. The effect on PMMA adsorption of water traces in solvent is emphasized: the adsorbed amount increases with the water concentration. Flat glass and silica are compared: on contrary of what is expected, adsorbed amount on glass is higher than on silica. This result is interpreted as due to the difference of behaviour between glass and silica with respect to water adsorption. {copyright} {ital 1996 American Institute of Physics.}

  6. Method of and apparatus for removing silicon from a high temperature sodium coolant

    DOE Patents [OSTI]

    Yunker, W.H.; Christiansen, D.W.

    1983-11-25T23:59:59.000Z

    This patent discloses a method of and system for removing silicon from a high temperature liquid sodium coolant system for a nuclear reactor. The sodium is cooled to a temperature below the silicon saturation temperature and retained at such reduced temperature while inducing high turbulence into the sodium flow for promoting precipitation of silicon compounds and ultimate separation of silicon compound particles from the liquid sodium.

  7. Go No-Go Recommendation for Sodium Borohydride for On-Board Vehicular Hydrogen Storage

    Fuel Cell Technologies Publication and Product Library (EERE)

    Independent review panel recommendation for go/no go decision on use of hydrolysis of sodium borohydride for hydrogen storage.

  8. E-Print Network 3.0 - affecting sodium hypochlorite Sample Search...

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

    -Partial list Chemical Incompatibilities Summary: hypochlorite, all oxidizing agents Carbon tetrachloride Sodium Chlorates Ammonium salts, acids, powdered metals... and...

  9. Teaching Sodium Fast Reactor Technology and Operation for the Present and Future Generations of SFR Users

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Teaching Sodium Fast Reactor Technology and Operation for the Present and Future Generations of SFR or development of sodium fast reactors and related experimental facilities. The sum of courses provided by CEA on sodium fast reactor design, technology, safety and operation experience, decommissioning aspects

  10. Ultracold Molecules from Ultracold Atoms: Interactions in Sodium and Lithium Gas

    E-Print Network [OSTI]

    Ultracold Molecules from Ultracold Atoms: Interactions in Sodium and Lithium Gas by Caleb from Ultracold Atoms: Interactions in Sodium and Lithium Gas by Caleb A Christensen Submitted of Philosophy Abstract The thesis presents results from experiments in which ultracold Sodium-6 and Lithium-23

  11. NiO-silica based nanostructured materials obtained by microemulsion assisted sol-gel procedure

    SciTech Connect (OSTI)

    Mihaly, M.; Comanescu, A.F. [University POLITEHNICA Bucharest, Faculty of Applied Chemistry and Materials Science, 1 Polizu, 011061 Bucharest (Romania)] [University POLITEHNICA Bucharest, Faculty of Applied Chemistry and Materials Science, 1 Polizu, 011061 Bucharest (Romania); Rogozea, A.E. [ILIE MURGULESCU Institute of Physical Chemistry of the Romanian Academy, 202 Splaiul Independentei, 060021 Bucharest (Romania)] [ILIE MURGULESCU Institute of Physical Chemistry of the Romanian Academy, 202 Splaiul Independentei, 060021 Bucharest (Romania); Vasile, E. [METAV Research and Development, 31 C.A. Rosetti, 020011 Bucharest (Romania)] [METAV Research and Development, 31 C.A. Rosetti, 020011 Bucharest (Romania); Meghea, A., E-mail: a.meghea@gmail.com [University POLITEHNICA Bucharest, Faculty of Applied Chemistry and Materials Science, 1 Polizu, 011061 Bucharest (Romania)

    2011-10-15T23:59:59.000Z

    Graphical abstract: TEM micrograph of NiO/SiO{sub 2} nanoparticles. Highlights: {yields} Microemulsion assisted sol-gel procedure for NiO silica nanomaterials synthesis. {yields} Controlling the size and shape of nanoparticles and avoiding their aggregation. {yields} Narrow band-gap semiconductors (energies <3 eV) absorbing VIS or near-UV light biologically and chemically inert semiconductors entrapping/coating in silica network. {yields} Low cost as the microemulsion is firstly used in water metallic cation extraction. -- Abstract: NiO-silica based materials have been synthesized by microemulsion assisted sol-gel procedure. The versatility of these soft nanotechnology techniques has been exploited in order to obtain different types of nanostructures, such as NiO nanoparticles, NiO silica coated nanoparticles and NiO embedded in silica matrix. These materials have been characterized by adequate structural and morphology techniques: DLS, HR-TEM/SAED, BET, AFM. Optical and semiconducting properties (band-gap values) of the synthesized materials have been quantified by means of VIS-NIR diffuse reflectance spectra, thus demonstrating their applicative potential in various electron transfer phenomena such as photocatalysis, electrochromic thin films, solid oxide fuel cells.

  12. Thickness controlled sol-gel silica films for plasmonic bio-sensing devices

    SciTech Connect (OSTI)

    Figus, Cristiana, E-mail: cristiana.figus@dsf.unica.it; Quochi, Francesco, E-mail: cristiana.figus@dsf.unica.it; Artizzu, Flavia, E-mail: cristiana.figus@dsf.unica.it; Saba, Michele, E-mail: cristiana.figus@dsf.unica.it; Marongiu, Daniela, E-mail: cristiana.figus@dsf.unica.it; Mura, Andrea; Bongiovanni, Giovanni [Dipartimento di Fisica - University of Cagliari, S.P. Km 0.7, I-09042 Monserrato (Canada) (Italy); Floris, Francesco; Marabelli, Franco; Patrini, Maddalena; Fornasari, Lucia [Dipartimento di Fisica - University of Pavia, Via Agostino Bassi 6, I-27100 Pavia (PV) (Italy); Pellacani, Paola; Valsesia, Andrea [Plasmore S.r.l. -Via Grazia Deledda 4, I-21020 Ranco (Vatican City State, Holy See) (Italy)

    2014-10-21T23:59:59.000Z

    Plasmonics has recently received considerable interest due to its potentiality in many fields as well as in nanobio-technology applications. In this regard, various strategies are required for modifying the surfaces of plasmonic nanostructures and to control their optical properties in view of interesting application such as bio-sensing, We report a simple method for depositing silica layers of controlled thickness on planar plasmonic structures. Tetraethoxysilane (TEOS) was used as silica precursor. The control of the silica layer thickness was obtained by optimizing the sol-gel method and dip-coating technique, in particular by properly tuning different parameters such as pH, solvent concentration, and withdrawal speed. The resulting films were characterized via atomic force microscopy (AFM), Fourier-transform (FT) spectroscopy, and spectroscopic ellipsometry (SE). Furthermore, by performing the analysis of surface plasmon resonances before and after the coating of the nanostructures, it was observed that the position of the resonance structures could be properly shifted by finely controlling the silica layer thickness. The effect of silica coating was assessed also in view of sensing applications, due to important advantages, such as surface protection of the plasmonic structure.

  13. Direct encapsulation of water-soluble drug into silica microcapsules for sustained release applications

    SciTech Connect (OSTI)

    Wang Jiexin; Wang Zhihui [Key Lab for Nanomaterials, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China); Chen Jianfeng [Key Lab for Nanomaterials, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China); Research Center of the Ministry of Education for High Gravity Engineering and Technology, Beijing University of Chemical Technology, Beijing 100029 (China)], E-mail: chenjf@mail.buct.edu.cn; Yun, Jimmy [Nanomaterials Technology Pte. Ltd., 28 Ayer Rajah Crescent 03-03, Singapore 139959 (Singapore)

    2008-12-01T23:59:59.000Z

    Direct encapsulation of water-soluble drug into silica microcapsules was facilely achieved by a sol-gel process of tetraethoxysilane (TEOS) in W/O emulsion with hydrochloric acid (HCl) aqueous solution containing Tween 80 and drug as well as cyclohexane solution containing Span 80. Two water-soluble drugs of gentamicin sulphate (GS) and salbutamol sulphate (SS) were chosen as model drugs. The characterization of drug encapsulated silica microcapsules by scanning electronic microscopy (SEM), FTIR, thermogravimetry (TG) and N{sub 2} adsorption-desorption analyses indicated that drug was successfully entrapped into silica microcapsules. The as-prepared silica microcapsules were uniform spherical particles with hollow structure, good dispersion and a size of 5-10 {mu}m, and had a specific surface area of about 306 m{sup 2}/g. UV-vis and thermogravimetry (TG) analyses were performed to determine the amount of drug encapsulated in the microcapsules. The BJH pore size distribution (PSD) of silica microcapsules before and after removing drug was examined. In vitro release behavior of drug in simulated body fluid (SBF) revealed that such system exhibited excellent sustained release properties.

  14. The use of sodium and/or potassium lactate to extend shelf-life and reduce sodium levels in precooked beef systems 

    E-Print Network [OSTI]

    Pagach, Denise Ann

    1992-01-01T23:59:59.000Z

    of the requirements for the degree of MASTER OF SCIENCE May 1992 Major Subject: Food Science and Technology THE USE OF SODIUM AND/OR POTASSIUM LACTATE TO EXTEND SHELF-LIFE AND REDUCE SODIUM LEVELS IN PRECOOKED BEEF SYSTEMS A Thesis by DENISE ANN PAGACH... ABSTRACT The Use of Sodium and/or Potassium Lactate to Extend Shelf-Life and Reduce Sodium Levels in Precooked Beef Systems. (May 1992) Denise Ann Pagach, B. S. , Texas AdtM University Chair of Advisory Committee: Dr. R. K. Miller Concern for food...

  15. Clinch River breeder reactor sodium fire protection system design and development

    SciTech Connect (OSTI)

    Foster, K.W.; Boasso, C.J.; Kaushal, N.N.

    1984-04-13T23:59:59.000Z

    To assure the protection of the public and plant equipment, improbable accidents were hypothesized to form the basis for the design of safety systems. One such accident is the postulated failure of the Intermediate Heat Transfer System (IHTS) piping within the Steam Generator Building (SGB), resulting in a large-scale sodium fire. This paper discusses the design and development of plant features to reduce the consequences of the accident to acceptable levels. Additional design solutions were made to mitigate the sodium spray contribution to the accident scenario. Sodium spill tests demonstrated that large sodium leaks can be safely controlled in a sodium-cooled nuclear power plant.

  16. Self-Assembled Silica Nano-Composite Polymer Electrolytes: Synthesis, Rheology & Electrochemistry

    SciTech Connect (OSTI)

    Khan, Saad A.: Fedkiw Peter S.; Baker, Gregory L.

    2007-01-24T23:59:59.000Z

    The ultimate objectives of this research are to understand the principles underpinning nano-composite polymer electrolytes (CPEs) and facilitate development of novel CPEs that are low-cost, have high conductivities, large Li+ transference numbers, improved electrolyte-electrode interfacial stability, yield long cycle life, exhibit mechanical stability and are easily processable. Our approach is to use nanoparticulate silica fillers to formulate novel composite electrolytes consisting of surface-modified fumed silica nano-particles in polyethylene oxides (PEO) in the presence of lithium salts. We intend to design single-ion conducting silica nanoparticles which provide CPEs with high Li+ transference numbers. We also will develop low-Mw (molecular weight), high-Mw and crosslinked PEO electrolytes with tunable properties in terms of conductivity, transference number, interfacial stability, processability and mechanical strength

  17. Strong strain rate effect on the plasticity of amorphous silica nanowires

    SciTech Connect (OSTI)

    Yue, Yonghai, E-mail: yueyonghai@buaa.edu.cn [Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, Beijing Key Laboratory of Bio-Inspired Energy Materials and Devices, School of Chemistry and Environment, Beihang University, Beijing 100191 (China); Zheng, Kun [Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing 100124 (China)

    2014-06-09T23:59:59.000Z

    With electron-beam (e-beam) off, in-situ tensile experiments on amorphous silica nanowires (NWs) were performed inside a transmission electron microscope (TEM). By controlling the loading rates, the strain rate can be adjusted accurately in a wide range. The result shows a strong strain rate effect on the plasticity of amorphous silica NWs. At lower strain rate, the intrinsic brittle materials exhibit a pronounced elongation higher than 100% to failure with obvious necking near ambient temperature. At the strain rate higher than 5.23?×?10{sup ?3}/s, the elongation of the NW decreased dramatically, and a brittle fracture feature behavior was revealed. This ductile feature of the amorphous silica NWs has been further confirmed with the in-situ experiments under optical microscopy while the effect of e-beam irradiation could be eliminated.

  18. Moisture sensor based on evanescent wave light scattering by porous sol-gel silica coating

    DOE Patents [OSTI]

    Tao, Shiquan; Singh, Jagdish P.; Winstead, Christopher B.

    2006-05-02T23:59:59.000Z

    An optical fiber moisture sensor that can be used to sense moisture present in gas phase in a wide range of concentrations is provided, as well techniques for making the same. The present invention includes a method that utilizes the light scattering phenomenon which occurs in a porous sol-gel silica by coating an optical fiber core with such silica. Thus, a porous sol-gel silica polymer coated on an optical fiber core forms the transducer of an optical fiber moisture sensor according to an embodiment. The resulting optical fiber sensor of the present invention can be used in various applications, including to sense moisture content in indoor/outdoor air, soil, concrete, and low/high temperature gas streams.

  19. SANS study of interaction of silica nanoparticles with BSA protein and their resultant structure

    SciTech Connect (OSTI)

    Yadav, Indresh, E-mail: vkaswal@barc.gov.in; Aswal, V. K., E-mail: vkaswal@barc.gov.in [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai-400085 (India); Kohlbrecher, J. [Laboratory for Neutron Scattering, Paul Scherrer Institute, CH-5232 PSI Villigen Switzerland (Switzerland)

    2014-04-24T23:59:59.000Z

    Small angle neutron scattering (SANS) has been carried out to study the interaction of anionic silica nanoparticles (88 Å) with globular protein Bovine Serum Albumin (BSA) (M.W. 66.4 kD) in aqueous solution. The measurements have been carried out on fixed concentration (1 wt %) of Ludox silica nanoparticles with varying concentration of BSA (0–5 wt %) at pH7. Results show that silica nanoparticles and BSA coexist as individual entities at low concentration of BSA where electrostatic repulsive interactions between them prevent their aggregation. However, as the concentration of BSA increases (? 0.5 wt %), it induces the attractive depletion interaction among nanoparticles leading to finally their aggregation at higher BSA concentration (2 wt %). The aggregates are found to be governed by the diffusion limited aggregation (DLA) morphology of fractal nature having fractal dimension about 2.4.

  20. Cleaning Cesium Radionuclides from BN-350 Primary Sodium

    SciTech Connect (OSTI)

    Romanenko, O.G.; Allen, K.J.; Wachs, D.M.; Planchon, H.P.; Wells, P.B.; Michelbacher, J.A.; Nazarenko, P.; Dumchev, I.; Maev, V.; Zemtzev, B.; Tikhomirov, L.; Yakovlev, V.; Synkov, A

    2005-04-15T23:59:59.000Z

    This paper reports the successful design and operation of a system to remove highly radioactive cesium from the sodium coolant of the BN-350 reactor in Aktau, Kazakhstan. As an international effort between the United States and the Republic of Kazakhstan, a cesium-trapping system was jointly designed, fabricated, installed, and successfully operated. The results are significant for a number of reasons, including (a) a significant reduction of radioactivity levels of the BN-350 coolant and reactor surfaces, thereby reducing exposure to workers during shutdown operations; (b) demonstration of scientific ideas; and (c) the engineering application of effective cesium trap deployment for commercial-sized liquid-metal reactors. About 255 300 GBq (6900 Ci) of cesium was trapped, and the {sup 137}Cs specific activity in BN-350 primary sodium was decreased from 296 MBq/kg (8000 {mu}Ci/kg) to 0.37 MBq/kg (10 {mu}Ci/kg) by using seven cesium traps containing reticulated vitreous carbon (RVC) as the cesium adsorbent. Cesium trapping was accomplished by pumping sodium from the primary circuit, passing it through a block of RVC within each trap, and returning the cleaned sodium to the primary circuit. Both to predict and to analyze the behavior of the cesium traps in the BN-350 reactor primary circuit, a model was developed that satisfactorily describes the observed results of the cesium trapping. By using this model, thermodynamic parameters, such as the heat of adsorption of cesium atoms on RVC and on internal piping surfaces of the BN-350 reactor primary circuit, -22.7 and -5.0 kJ/mole, respectively, were extracted from the experimental data.

  1. Selective Adsorption of Sodium Aluminum Fluoride Salts from Molten Aluminum

    SciTech Connect (OSTI)

    Leonard S. Aubrey; Christine A. Boyle; Eddie M. Williams; David H. DeYoung; Dawid D. Smith; Feng Chi

    2007-08-16T23:59:59.000Z

    Aluminum is produced in electrolytic reduction cells where alumina feedstock is dissolved in molten cryolite (sodium aluminum fluoride) along with aluminum and calcium fluorides. The dissolved alumina is then reduced by electrolysis and the molten aluminum separates to the bottom of the cell. The reduction cell is periodically tapped to remove the molten aluminum. During the tapping process, some of the molten electrolyte (commonly referred as “bath” in the aluminum industry) is carried over with the molten aluminum and into the transfer crucible. The carryover of molten bath into the holding furnace can create significant operational problems in aluminum cast houses. Bath carryover can result in several problems. The most troublesome problem is sodium and calcium pickup in magnesium-bearing alloys. Magnesium alloying additions can result in Mg-Na and Mg-Ca exchange reactions with the molten bath, which results in the undesirable pickup of elemental sodium and calcium. This final report presents the findings of a project to evaluate removal of molten bath using a new and novel micro-porous filter media. The theory of selective adsorption or removal is based on interfacial surface energy differences of molten aluminum and bath on the micro-porous filter structure. This report describes the theory of the selective adsorption-filtration process, the development of suitable micro-porous filter media, and the operational results obtained with a micro-porous bed filtration system. The micro-porous filter media was found to very effectively remove molten sodium aluminum fluoride bath by the selective adsorption-filtration mechanism.

  2. Ultra-large bandwidth hollow-core guiding in all-silica Bragg fibers with nano-supports

    E-Print Network [OSTI]

    Huang, Yanyi

    Ultra-large bandwidth hollow-core guiding in all-silica Bragg fibers with nano-supports Guillaume 420, 650-653 (2002). 7. C. M. Smith et al., "Low-loss hollow-core silica/air photonic bandgap fibre yong@its.caltech.edu. Abstract: We demonstrate a new class of hollow-core Bragg fibers

  3. Very large-scale structures in sintered silica aerogels as evidenced by atomic force microscopy and ultra-small angle

    E-Print Network [OSTI]

    Demouchy, Sylvie

    Very large-scale structures in sintered silica aerogels as evidenced by atomic force microscopy of silica aerogels has been extensively studied mainly by scattering techniques (neutrons, X-rays, light) and atomic force microscopy (AFM) experiments have been carried out on aerogels at dierent steps of densi

  4. Structure and Dynamics of Acetonitrile Confined in a Silica Nanopore Liwen Cheng, Joseph A. Morrone, and B. J. Berne*

    E-Print Network [OSTI]

    Berne, Bruce J.

    Structure and Dynamics of Acetonitrile Confined in a Silica Nanopore Liwen Cheng, Joseph A. Morrone York 10027, United States ABSTRACT: Acetonitrile confined in silica nanopores with surfaces of varying. It is found that acetonitrile orders into bilayer like structures near the surface, in agreement with prior

  5. Water, chloroform, acetonitrile, and atrazine adsorption to the amorphous silica surface studied by vibrational sum frequency generation spectroscopy

    E-Print Network [OSTI]

    Water, chloroform, acetonitrile, and atrazine adsorption to the amorphous silica surface studied the air­silica interface before, during, and after adsorption of water, chloroform, acetonitrile the compounds. Adsorption of chloro- form and acetonitrile was weaker compared to water. Binding to the surface

  6. On-chip generation and demultiplexing of quantum correlated photons using a silicon-silica monolithic photonic integration platform

    E-Print Network [OSTI]

    Nobuyuki Matsuda; Peter Karkus; Hidetaka Nishi; Tai Tsuchizawa; William J. Munro; Hiroki Takesue; Koji Yamada

    2014-09-14T23:59:59.000Z

    We demonstrate the generation and demultiplexing of quantum correlated photons on a monolithic photonic chip composed of silicon and silica-based waveguides. Photon pairs generated in a nonlinear silicon waveguide are successfully separated into two optical channels of an arrayed-waveguide grating fabricated on a silica-based waveguide platform.

  7. Development of 3-D magnetic nano-arrays by electrodeposition into mesoporous silica.

    SciTech Connect (OSTI)

    Campbell, R.; Manning, J.; Bakker, M.G.; Li, X.; Lee, D.R.; Wang, J.; X-Ray Science Division; Univ. of Alabama

    2006-01-01T23:59:59.000Z

    The development of periodic nanostructures fabricated by self-assembly of surfactants and block co-polymers has opened up the possibility of generating periodic magnetic nanostructures of types not accessible by self-assembly of nano-particles. The fabrication of mesoporous silica thin films around self-assembled block co-polymers is well established. Common structures for such films are SBA-15 which consists of hexagonal arrays of cylindrical pores and SBA-16 which has face centered arrays of spherical voids. These pores are connected by 1-2 nm thick flaws in the continuous silica phase producing an effectively continuous porous phase. After removal of the block co-polymer template, electrodeposition into the mesoporous silica thin films produces arrays of 5-10 nm diameter nano-wires and nano-particles. We have demonstrated that such materials can be fabricated on a wide range of metal substrates. Characterization by Scanning Electron Microscopies shows that the mesoporous silica is well ordered over micron scale areas. Grazing Incidence Small Angle X-ray Scattering (GISAXS) studies shows diffraction spots, consistent with the entire film being well ordered. GISAXS also shows that the mesoporous silica films survive removal of the template and electrodeposition of nickel and cobalt into the mesoporous silica films. Such films are of interest for their magnetic properties, as the nanophase and scale can be independently varied. Further, the presence of nanowires inside an insulator suggests that these films might also be of interest as the current confining element for Confined Current Path-Current Perpendicular to Plane GMR sensors.

  8. A comparison of mechanical properties and scaling law relationships for silica aerogels and their organic counterparts

    SciTech Connect (OSTI)

    Pekala, R.W.; Hrubesh, L.W.; Tillotson, T.M.; Alviso, C.T.; Poco, J.F.; LeMay, J.D.

    1990-08-01T23:59:59.000Z

    Aerogels are a special class of open-cell foams derived from the supercritical extraction of highly crosslinked, inorganic or organic gels. The resultant materials have ultrafine cell/pore sizes (< 100 nm), high surface areas (350--1000m{sup 2}/g), and a microstructure composed of interconnected colloidal-like particles or polymeric chains with characteristic diameters of 10 nm. TEM and SAXS show that this microstructure is sensitive to variations in processing conditions that influence crosslinking chemistry and growth processes prior to gelation. Traditional silica aerogels are prepared via the hydrolysis and condensation of tetramethoxy silane (TMOS) or tetraethoxy silane (TEOS). Factors such as pH and the (H{sub 2}O)/(TMOS) ratio affect the microstructure of the dried aerogel. It is generally accepted that polymeric' silica aerogels result from acid catalysis while colloidal'silica aerogels result from base catalysis. Recently, Hrubesh and Tillotson developed a new condensed silica' procedure for obtaining silica aerogels with densities as low as 0.004g/cc, i.e. only 3{times} the density of air. Organic aerogels are formed from the aqueous, polycondensation of (1) resorcinol/formaldehyde or (2) melamine/formaldehyde. The microstructure of the resorcinol-formaldehyde (RF) aerogels is dictated by the amount of base catalyst used in the sol-gel polymerization. In addition, these materials can be pyrolyzed in an inert atmosphere to form vitreous carbon aerogels. Melamine- formaldehyde (MF) aerogels that are both colorless and transparent are only formed under acidic conditions (i.e. pH = 1--2). In this paper, the microstructural dependence and scaling law relationships for the compressive modulus of silica, carbon, RF, and MF aerogels will be discussed in detail. 17 refs., 1 fig.

  9. Sodium-Bearing Waste Treatment, Applied Technology Plan

    SciTech Connect (OSTI)

    Lance Lauerhass; Vince C. Maio; S. Kenneth Merrill; Arlin L. Olson; Keith J. Perry

    2003-06-01T23:59:59.000Z

    Settlement Agreement between the Department of Energy and the State of Idaho mandates treatment of sodium-bearing waste at the Idaho Nuclear Technology and Engineering Center within the Idaho National Engineering and Environmental Laboratory. One of the requirements of the Settlement Agreement is to complete treatment of sodium-bearing waste by December 31, 2012. Applied technology activities are required to provide the data necessary to complete conceptual design of four identified alternative processes and to select the preferred alternative. To provide a technically defensible path forward for the selection of a treatment process and for the collection of needed data, an applied technology plan is required. This document presents that plan, identifying key elements of the decision process and the steps necessary to obtain the required data in support of both the decision and the conceptual design. The Sodium-Bearing Waste Treatment Applied Technology Plan has been prepared to provide a description/roadmap of the treatment alternative selection process. The plan details the results of risk analyzes and the resulting prioritized uncertainties. It presents a high-level flow diagram governing the technology decision process, as well as detailed roadmaps for each technology. The roadmaps describe the technical steps necessary in obtaining data to quantify and reduce the technical uncertainties associated with each alternative treatment process. This plan also describes the final products that will be delivered to the Department of Energy Idaho Operations Office in support of the office's selection of the final treatment technology.

  10. Applications of Geothermally-Produced Colloidal Silica in Reservoir Management - Smart Gels

    SciTech Connect (OSTI)

    Hunt, Jonathan

    2013-01-31T23:59:59.000Z

    In enhanced geothermal systems (EGS) the reservoir permeability is often enhanced or created using hydraulic fracturing. In hydraulic fracturing, high fluid pressures are applied to confined zones in the subsurface usually using packers to fracture the host rock. This enhances rock permeability and therefore conductive heat transfer to the circulating geothermal fluid (e.g. water or supercritical carbon dioxide). The ultimate goal is to increase or improve the thermal energy production from the subsurface by either optimal designs of injection and production wells or by altering the fracture permeability to create different zones of circulation that can be exploited in geothermal heat extraction. Moreover, hydraulic fracturing can lead to the creation of undesirable short-circuits or fast flow-paths between the injection and extraction wells leading to a short thermal residence time, low heat recovery, and thus a short-life of the EGS. A potential remedy to these problems is to deploy a cementing (blocking, diverting) agent to minimize short-cuts and/or create new circulation cells for heat extraction. A potential diverting agent is the colloidal silica by-product that can be co-produced from geothermal fluids. Silica gels are abundant in various surface and subsurface applications, yet they have not been evaluated for EGS applications. In this study we are investigating the benefits of silica gel deployment on thermal response of an EGS, either by blocking short-circuiting undesirable pathways as a result of diverting the geofluid to other fractures; or creating, within fractures, new circulation cells for harvesting heat through newly active surface area contact. A significant advantage of colloidal silica is that it can be co-produced from geothermal fluids using an inexpensive membrane-based separation technology that was developed previously using DOE-GTP funding. This co-produced silica has properties that potentially make it useful as a fluid diversion agent for subsurface applications. Colloidal silica solutions exist as low-viscosity fluids during their “induction period” but then undergo a rapid increase in viscosity (gelation) to form a solid gel. The length of the induction period can be manipulated by varying the properties of the solution, such as silica concentration and colloid size. We believe it is possible to produce colloidal silica gels suitable for use as diverting agents for blocking undesirable fast-paths which result in short-circuiting the EGS once hydraulic fracturing has been deployed. In addition, the gels could be used in conventional geothermal fields to increase overall energy recovery by modifying flow.

  11. Hyperthermia HeLa cell treatment with silica coated manganese oxide nanoparticles

    E-Print Network [OSTI]

    Villanueva, A; Alonso, JM; Rueda, T; Martínez, A; Crespo, P; Morales, MP; Fernandez, MA Gonzalez; Valdes, J; Rivero, G

    2009-01-01T23:59:59.000Z

    HeLa tumour cells incubated with ferromagnetic nanoparticles of manganese oxide perovskite La0.56(SrCa)0.22MnO3 were treated with a high frequency alternating magnetic field. The particles were previously coated with silica to improve their biocompatibility. The control assays made with HeLa tumour cells showed that cell survival and growth rate were not affected by the particle internalization in cells, or by the electromagnetic field on cells without nanoparticles. The application of an alternating electromagnetic field to cells incubated with this silica coated manganese oxide induced a significant cellular damage that finally lead to cell death by an apoptotic mechanism.

  12. Monodisperse metal nanoparticle catalysts on silica mesoporous supports: synthesis, characterizations, and catalytic reactions

    SciTech Connect (OSTI)

    Somorjai, G.A.

    2009-09-14T23:59:59.000Z

    The design of high performance catalyst achieving near 100% product selectivity at maximum activity is one of the most important goals in the modern catalytic science research. To this end, the preparation of model catalysts whose catalytic performances can be predicted in a systematic and rational manner is of significant importance, which thereby allows understanding of the molecular ingredients affecting the catalytic performances. We have designed novel 3-dimensional (3D) high surface area model catalysts by the integration of colloidal metal nanoparticles and mesoporous silica supports. Monodisperse colloidal metal NPs with controllable size and shape were synthesized using dendrimers, polymers, or surfactants as the surface stabilizers. The size of Pt, and Rh nanoparticles can be varied from sub 1 nm to 15 nm, while the shape of Pt can be controlled to cube, cuboctahedron, and octahedron. The 3D model catalysts were generated by the incorporation of metal nanoparticles into the pores of mesoporous silica supports via two methods: capillary inclusion (CI) and nanoparticle encapsulation (NE). The former method relies on the sonication-induced inclusion of metal nanoparticles into the pores of mesoporous silica, whereas the latter is performed by the encapsulation of metal nanoparticles during the hydrothermal synthesis of mesoporous silica. The 3D model catalysts were comprehensively characterized by a variety of physical and chemical methods. These catalysts were found to show structure sensitivity in hydrocarbon conversion reactions. The Pt NPs supported on mesoporous SBA-15 silica (Pt/SBA-15) displayed significant particle size sensitivity in ethane hydrogenolysis over the size range of 1-7 nm. The Pt/SBA-15 catalysts also exhibited particle size dependent product selectivity in cyclohexene hydrogenation, crotonaldehyde hydrogenation, and pyrrole hydrogenation. The Rh loaded SBA-15 silica catalyst showed structure sensitivity in CO oxidation reaction. In addition, Pt-mesoporous silica core-shell structured NPs (Pt{at}mSiO{sub 2}) were prepared, where the individual Pt NP is encapsulated by the mesoporous silica layer. The Pt{at}mSiO{sub 2} catalysts showed promising catalytic activity in high temperature CO oxidation. The design of catalytic structures with tunable parameters by rational synthetic methods presents a major advance in the field of catalyst synthesis, which would lead to uncover the structure-function relationships in heterogeneous catalytic reactions.

  13. Decomposition of cumyl hydroperoxide in the presence of sulphonated silica in a flow-type system

    SciTech Connect (OSTI)

    Shelpakova, N.A.; Ioffa, A.F.

    1993-12-31T23:59:59.000Z

    An investigation has been made of the decomposition of cumyl hydroperoxide (CHP) in the presence of silica-based sulphocationites in a flow-type system. It was established that the given specimens are effective catalysts for the decomposition of CHP into phenol and acetone. It was shown that, in the course of the process, no irreversible poisoning of the surface of the catalyst by the products of CHP decomposition occurs. Data of chromatographic analysis of the products of CHP decomposition in the presence of sulphuric acid and silica-based sulphocationites are given.

  14. Method and composition in which metal hydride particles are embedded in a silica network

    DOE Patents [OSTI]

    Heung, Leung K. (Aiken, SC)

    1999-01-01T23:59:59.000Z

    A silica embedded metal hydride composition and a method for making such a composition. The composition is made via the following process: A quantity of fumed silica is blended with water to make a paste. After adding metal hydride particles, the paste is dried to form a solid. According to one embodiment of the invention, the solid is ground into granules for use of the product in hydrogen storage. Alternatively, the paste can be molded into plates or cylinders and then dried for use of the product as a hydrogen filter. Where mechanical strength is required, the paste can be impregnated in a porous substrate or wire network.

  15. Applications of Geothermally-Produced Colloidal Silica in Reservoir Management - Smart Gels

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Hunt, Jonathan

    In enhanced geothermal systems (EGS) the reservoir permeability is often enhanced or created using hydraulic fracturing. In hydraulic fracturing, high fluid pressures are applied to confined zones in the subsurface usually using packers to fracture the host rock. This enhances rock permeability and therefore conductive heat transfer to the circulating geothermal fluid (e.g. water or supercritical carbon dioxide). The ultimate goal is to increase or improve the thermal energy production from the subsurface by either optimal designs of injection and production wells or by altering the fracture permeability to create different zones of circulation that can be exploited in geothermal heat extraction. Moreover, hydraulic fracturing can lead to the creation of undesirable short-circuits or fast flow-paths between the injection and extraction wells leading to a short thermal residence time, low heat recovery, and thus a short-life of the EGS. A potential remedy to these problems is to deploy a cementing (blocking, diverting) agent to minimize short-cuts and/or create new circulation cells for heat extraction. A potential diverting agent is the colloidal silica by-product that can be co-produced from geothermal fluids. Silica gels are abundant in various surface and subsurface applications, yet they have not been evaluated for EGS applications. In this study we are investigating the benefits of silica gel deployment on thermal response of an EGS, either by blocking short-circuiting undesirable pathways as a result of diverting the geofluid to other fractures; or creating, within fractures, new circulation cells for harvesting heat through newly active surface area contact. A significant advantage of colloidal silica is that it can be co-produced from geothermal fluids using an inexpensive membrane-based separation technology that was developed previously using DOE-GTP funding. This co-produced silica has properties that potentially make it useful as a fluid diversion agent for subsurface applications. Colloidal silica solutions exist as low-viscosity fluids during their “induction period” but then undergo a rapid increase in viscosity (gelation) to form a solid gel. The length of the induction period can be manipulated by varying the properties of the solution, such as silica concentration and colloid size. We believe it is possible to produce colloidal silica gels suitable for use as diverting agents for blocking undesirable fast-paths which result in short-circuiting the EGS once hydraulic fracturing has been deployed. In addition, the gels could be used in conventional geothermal fields to increase overall energy recovery by modifying flow.

  16. Preparation of Mesoporous Silica Templated Metal Nanowire Films on Foamed Nickel Substrates

    SciTech Connect (OSTI)

    Campbell, Roger [University of Alabama, Tuscaloosa; Kenik, Edward A [ORNL; Bakker, Martin [University of Alabama, Tuscaloosa; Havrilla, George [Los Alamos National Laboratory (LANL); Montoya, Velma [Los Alamos National Laboratory (LANL); Shamsuzzoha, Mohammed [University of Alabama, Tuscaloosa

    2006-01-01T23:59:59.000Z

    A method has been developed for the formation of high surface area nanowire films on planar and three-dimensional metal electrodes. These nanowire films are formed via electrodeposition into a mesoporous silica film. The mesoporous silica films are formed by a sol-gel process using Pluronic tri-block copolymers to template mesopore formation on both planar and three-dimensional metal electrodes. Surface area increases of up to 120-fold have been observed in electrodes containing a templated film when compared to the same types of electrodes without the templated film.

  17. Treatment of domestic wastewater for reuse with activated silica and magnesia 

    E-Print Network [OSTI]

    Lindner, John Howard

    1985-01-01T23:59:59.000Z

    and lime are effective at removing these components' The effectiveness of these coagulants was determined by running a series of jar tests on treated domestic wastewater over a range of pH values. Samples were taken of each coagulant dose added and a... of activated silica in combination with 60 mg/1 alum. Both series 20 were run at pH values of 4, 5, 6, 7, 8 and 9. A third series of jar tests were conducted with low doses of activated silica and sufficient lime to obtain a pH of 9, 10 and 11...

  18. Bulk and surface laser damage of silica by picosecond and nanosecond pulses at 1064 nm

    SciTech Connect (OSTI)

    Smith, Arlee V.; Do, Binh T

    2008-09-10T23:59:59.000Z

    We measured bulk and surface dielectric breakdown thresholds of pure silica for 14 ps and 8 ns pulses of 1064 nm light. The thresholds are sharp and reproducible. For the 8 ns pulses the bulk threshold irradiance is 4.75 {+-} 0.25 kW/{mu}m{sup 2}. The threshold is approximately three times higher for 14 ps pulses. For 8 ns pulses the input surface damage threshold can be made equal to the bulk threshold by applying an alumina or silica surface polish.

  19. Sodium Chloride interaction with solvated and crystalline cellulose : sodium ion affects the tetramer and fibril in aqueous solution

    E-Print Network [OSTI]

    Bellesia, Giovanni

    2013-01-01T23:59:59.000Z

    Inorganic salts are a natural component of biomass which have a significant effect on the product yields from a variety of biomass conversion processes. Understanding their effect on biomass at the microscopic level can help discover their mechanistic role. We present a study of the effect of aqueous sodium chloride (NaCl) on the largest component of biomass, cellulose, focused on the thermodynamic and structural effect of a sodium ion on the cellulose tetramer, and fibril. Replica exchange molecular dynamics simulations of a cellulose tetramer reveal a number of preferred cellulose-Na contacts and bridging positions. Large scale MD simulations on a model cellulose fibril find that Na+ perturbs the hydroxymethyl rotational state population and consequently disrupts the "native" hydrogen bonding network.

  20. Acidity and catalytic activity of zeolite catalysts bound with silica and alumina

    E-Print Network [OSTI]

    Wu, Xianchun

    2004-09-30T23:59:59.000Z

    of applications as catalysts in the petroleum refining and chemical industry. Because of their poor self- binding property, they need to be bound with a binder (matrix) such as silica, alumina, clay, or their mixture to produce a desired physical shape...

  1. Fluorocarbon plasma etching and profile evolution of porous low-dielectric-constant silica

    E-Print Network [OSTI]

    Kushner, Mark

    of PS, a feature profile model has been integrated with a plasma equipment model. To focus on issuesFluorocarbon plasma etching and profile evolution of porous low-dielectric-constant silica Arvind silicon dioxide PS is one such material. To address scaling issues during fluorocarbon plasma etching

  2. Spectroscopic Studies of Atmospheric Relevant Air-Aqueous and Air-Silica DISSERTATION

    E-Print Network [OSTI]

    Spectroscopic Studies of Atmospheric Relevant Air-Aqueous and Air-Silica Interfaces DISSERTATION in Environmental Science The Ohio State University 2010 Dissertation Committee: Heather C. Allen, Advisor Linda the interfaces and surfaces of the systems discussed in this dissertation. Complementary vibrational Raman

  3. Adsorption and onset of lubrication by a double-chained cationic surfactant on silica

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Adsorption and onset of lubrication by a double-chained cationic surfactant on silica surfaces cationic surfactant has been investigated at high normal contact pressures. Comparison with adsorption to this dispersion to7 participate in lubrication. However, it is well known that adsorption of sur-8 factants

  4. Mechanical reliability of silica optical fiber: a case study for a biomedical application

    E-Print Network [OSTI]

    Matthewson, M. John

    Mechanical reliability of silica optical fiber: a case study for a biomedical application Yunn, Piscataway, NJ 08854-8065 ABSTRACT The mechanical reliability of optical fiber used in certain biomedical the fiber can be safely used. In this paper we study two commercially available optical fibers designed

  5. Environmental effects on fatigue and lifetime predictions for silica optical fibers

    E-Print Network [OSTI]

    Matthewson, M. John

    Environmental effects on fatigue and lifetime predictions for silica optical fibers M. John optical fiber on the environmental parameters temperature, humidity and pH. It is shown that the stress used by the fiber optics industry provides a good fit to fatigue data for high strength fiber

  6. Partial oxidation of methanol over highly dispersed vanadia supported on silica SBA-15

    E-Print Network [OSTI]

    Bell, Alexis T.

    Partial oxidation of methanol over highly dispersed vanadia supported on silica SBA-15 C. Hessa 2005; accepted 6 August 2005 The partial oxidation of methanol to formaldehyde (FA) was studied over vanadia partly agglomerates into vanadia crystallites during methanol oxidation. KEY WORDS: supported

  7. Kinetics of degradation during fatigue and aging of fused silica optical fiber M. John Matthewson

    E-Print Network [OSTI]

    Matthewson, M. John

    Kinetics of degradation during fatigue and aging of fused silica optical fiber M. John Matthewson; degradation proceeds at an accelerated rate beyond the knee. This behavior leads to shorter lifetimes than predicted from short term data and to strength degradation even in the absence of an applied stress which

  8. Hydrophobicity of Hydroxylated Amorphous Fused Silica Surfaces Oleksandr Isaienko and Eric Borguet*

    E-Print Network [OSTI]

    Borguet, Eric

    in the atmosphere and in groundwater by silica colloids, heterogeneous catalysis, and petroleum extraction.1 Since water appears to be present on the surfaces of practically all solid minerals, including various forms as well as for the improvement of oil extraction from sands. However, in order to further the knowledge

  9. Acoustic and Thermal Characterization of Oil Migration, Gas Hydrates Formation and Silica Diagenesis

    E-Print Network [OSTI]

    Guerin, Gilles

    Rights Reserved #12;ABSTRACT Acoustic and Thermal Characterization of Oil Migration, Gas HydratesAcoustic and Thermal Characterization of Oil Migration, Gas Hydrates Formation and Silica is applied to two reservoirs in the Gulf of Mexico. In the last chapter, we present the thermal regime

  10. VISCOSITY OF AMORPHOUS SILICA WITHIN DOREMUS APPROACH Michael I. Ojovan, William E. Lee, Russell J. Hand*

    E-Print Network [OSTI]

    Sheffield, University of

    VISCOSITY OF AMORPHOUS SILICA WITHIN DOREMUS APPROACH Michael I. Ojovan, William E. Lee, Russell J flow is the two-exponential formula of the viscosity AT exp(B/RT)(1+C exp(D/RT)). Derived formula of viscosity has the Arrhenius-type behaviour in both high and low temperature limits and has a form similar

  11. Effectiveness of cabs for dust and silica control on mobile mining equipment

    SciTech Connect (OSTI)

    Garcia, J.J.; Gresh, R.E.; Gareis, M.B.; Haney, R.A.

    1999-07-01T23:59:59.000Z

    The Mine Safety and Health Administration (MSHA) has conducted a study to evaluate the effectiveness of cabs for controlling silica dust exposure during operation of mobile mining equipment. This study focused on bulldozers, front-end loaders and haul trucks, was conducted at surface coal mining operations and underground metal and nonmetal mining operations. Each piece of equipment tested was equipped with a cab. The vehicles sampled were from a range of manufacturers having different types of filter media and air intake configurations. The purpose of this study was to determine the reduction of dust and silica exposure that could be achieved through the use of a well-maintained cab. For each piece of equipment, dust and silica concentrations inside and outside the cab were determined and compared. In some cases, filtration efficiencies could be calculated. A properly designed environmental cab is sealed, has an intake air filtration system, and a heating and cooling system. Cabs should have good seals around the doors and windows. Factors such as cab pressurization filtration systems, filter media, and maintenance practices were also examined. In some cases, dust and silica reduction of 90 to 95% were observed.

  12. Synthesis and Characterization of Silica-Coated Iron Oxide Nanoparticles in Microemulsion: The Effect of Nonionic

    E-Print Network [OSTI]

    Tan, Weihong

    in magnetic disk drive spindles, optical memory devices, magnetic inks for bank checks, magnetic refrigeration, crystallinity, and the magnetic properties have been studied. The iron oxide nanoparticles are formed to study both uncoated and silica-coated iron oxide nanoparticles. All these particles show magnetic

  13. Incorporation of H2 in vitreous silica, qualitative and quantitative determination from Raman and infrared

    E-Print Network [OSTI]

    Boyer, Edmond

    the quench. #12;1. Introduction The incorporation of volatiles such as noble gases, carbon dioxide and water properties affected by the presence of the volatiles and their related species in the silicate network (see] and to affect optical properties of vitreous silica [14, 15]. Therefore, the dissolution mechanisms of water

  14. Design of a full silica pulse compression grating Nicolas Bonod,1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    is numerically studied for the compression of ultra-short pulses. The silica is therefore the only solid material are used in the compression of ultra-short pulses amplified by the so-called « frequency drift » method laser induced damage threshold. In comparison to gratings engraved on a dielectric stack (MLD

  15. Characterization of the intrinsic strength between epoxy and silica using a multiscale approach

    E-Print Network [OSTI]

    Buehler, Markus J.

    , we report a model to predict the intrinsic strength between organic and inorganic materials, based energy surface between attached and detached states of the bonded system and scaled up to incorporate readily in many other polymers. Silica, commonly found material in nature in the form of sand or quartz

  16. TESLA-FEL 2004-01 Silica Aerogel Radiators for Bunch Length

    E-Print Network [OSTI]

    TESLA-FEL 2004-01 Silica Aerogel Radiators for Bunch Length Measurements J. B¨ahr a , V. Djordjadze aerogel are used to measure the electron bunch length at the photo injector test facility at DESY Zeuthen by the usage of aerogel is calculated analytically and Monte Carlo simulations are performed. It is shown

  17. Rapid synthesis of polymer-silica hybrid nanofibers by biomimetic mineralization

    E-Print Network [OSTI]

    Mather, Patrick T.

    Rapid synthesis of polymer-silica hybrid nanofibers by biomimetic mineralization Pritesh A. Patel. Such a simple route to rapid formation of organic-inorganic hybrid nanofibers could have applications ranging from catalysis to tissue engineering, and nanocomposites in general. Ó 2009 Elsevier Ltd. All rights

  18. Ordered mesoporous silica nanoparticles with and without embedded iron oxide nanoparticles: structure evolution during synthesis

    E-Print Network [OSTI]

    Gruner, Sol M.

    - functional nanocomposites, in which properties of individual components are combined to create new features with metals and metal oxides results in hybrid mesoporous silica nanoparticles with combi- nations of properties. Such hybrids could be used in applications, such as drug delivery, MRI and catalysis.3

  19. Friction and Heat Transfer Characteristics of Silica and CNT Nanofluids in a Tube Flow

    E-Print Network [OSTI]

    Kostic, Milivoje M.

    Friction and Heat Transfer Characteristics of Silica and CNT Nanofluids in a Tube Flow MILIVOJE M of nanofluids in tube flow has been developed, instrumented and computerized. It has been calibrated using) nanofluids show peculiar results with substantial friction drag reduction and heat transfer enhancement

  20. Plasticity-induced structural anisotropy of silica glass C. L. Rountree1

    E-Print Network [OSTI]

    Boyer, Edmond

    Plasticity-induced structural anisotropy of silica glass C. L. Rountree1 , D. Vandembroucq2 , M anisotropic structure after extended shear plastic flow. This anisotropy which survives for an un- stressed tetrahedra microstructure remains mostly unaltered. PACS numbers: 62.20.F, 81.05.Kf Plasticity of amorphous

  1. The Effect of Silica Nanoparticles on Corrosion of Steel by Molten Carbonate Eutectics 

    E-Print Network [OSTI]

    Padmanaban Iyer, Ashwin

    2011-08-08T23:59:59.000Z

    The effect of silica nanoparticles on corrosion of steel by molten carbonate eutectic (42.7 percent Li2CO3, K2CO3) was investigated. The experimental design was based on static coupon immersion methodology where a coupon (material under study...

  2. Silica Supported Ceria Nanoparticles: A Hybrid Nanostructure To Increase Stability And Surface Reactivity Of Nano-crystalline Ceria

    SciTech Connect (OSTI)

    Munusamy, Prabhakaran; Sanghavi, Shail P.; Varga, Tamas; Thevuthasan, Suntharampillai

    2014-01-21T23:59:59.000Z

    The mixed oxidation state (3+/4+) of ceria nanoparticles of smaller sizes make them attractive materials for their catalytic antioxidant biological properties. However the unmodified smaller ceria nanoparticles are limited in their use due to particles agglomeration and reduced surface chemical reactivity in the solutions used to disperse the nanoparticles. This work describes an effort to stabilize small ceria nanoparticles, retaining their desired activity, on a larger stable silica support. The ceria nanoparticles attached to silica was synthesized by a solution synthesis technique in which the surface functional groups of silica nanoparticles were found to be essential for the formation of smaller ceria nanoparticles. The surface chemical and vibrational spectroscopy analysis revealed cerium–silicate (Ce-O-Si) covalent bond linkage between silica and cerium oxide nanoparticles. The colloidal properties (agglomerate particle size and suspension stability) of ceria attached to silica was significantly improved due to inherent physico-chemical characteristics of silica against random collision and gravitation settling as opposed to unmodified ceria nanoparticles in solution. The bio-catalytic activity of ceria nanoparticles in the 3+ oxidation state was not found to be limited by attachment to the silica support as measured by free radical scavenging activity in different biological media conditions.

  3. High Sodium Simulant Testing To Support SB8 Sludge Preparation

    SciTech Connect (OSTI)

    Newell, J. D.

    2012-09-19T23:59:59.000Z

    Scoping studies were completed for high sodium simulant SRAT/SME cycles to determine any impact to CPC processing. Two SRAT/SME cycles were performed with simulant having sodium supernate concentration of 1.9M at 130% and 100% of the Koopman Minimum Acid requirement. Both of these failed to meet DWPF processing objectives related to nitrite destruction and hydrogen generation. Another set of SRAT/SME cycles were performed with simulant having a sodium supernate concentration of 1.6M at 130%, 125%, 110%, and 100% of the Koopman Minimum Acid requirement. Only the run at 110% met DWPF processing objectives. Neither simulant had a stoichiometric factor window of 30% between nitrite destruction and excessive hydrogen generation. Based on the 2M-110 results it was anticipated that the 2.5M stoichiometric window for processing would likely be smaller than from 110-130%, since it appeared that it would be necessary to increase the KMA factor by at least 10% above the minimum calculated requirement to achieve nitrite destruction due to the high oxalate content. The 2.5M-130 run exceeded the DWPF hydrogen limits in both the SRAT and SME cycle. Therefore, testing of this wash endpoint was halted. This wash endpoint with this minimum acid requirement and mercury-noble metal concentration profile appears to be something DWPF should not process due to an overly narrow window of stoichiometry. The 2M case was potentially processable in DWPF, but modifications would likely be needed in DWPF such as occasionally accepting SRAT batches with undestroyed nitrite for further acid addition and reprocessing, running near the bottom of the as yet ill-defined window of allowable stoichiometric factors, potentially extending the SRAT cycle to burn off unreacted formic acid before transferring to the SME cycle, and eliminating formic acid additions in the frit slurry.

  4. Modelling of ultrasonic propagation in turbulent liquid sodium with temperature gradient

    SciTech Connect (OSTI)

    Massacret, N. [CEA, DEN, Nuclear Technology Department, F-13108 Saint-Paul-Lez-Durance (France); Aix-Marseille Université, LMA UPR 7051 CNRS, site LCND, 13625 Aix-en-Provence (France); Moysan, J., E-mail: joseph.moysan@univ-amu.fr; Ploix, M. A.; Corneloup, G. [Aix-Marseille Université, LMA UPR 7051 CNRS, site LCND, 13625 Aix-en-Provence (France); Jeannot, J. P. [CEA, DEN, Nuclear Technology Department, F-13108 Saint-Paul-Lez-Durance (France)

    2014-05-28T23:59:59.000Z

    The use of ultrasonic instrumentation in sodium-cooled fast reactors requires to understand and to predict how ultrasonic waves can be deflected, slowed down or speeded up, depending on the thermo-hydraulic characteristics of the liquid sodium. These thermo-hydraulic characteristics are mainly the local temperature and flow speed of the sodium. In this study we show that ray theory can be used to simulate ultrasonic propagation in a medium similar to the core of a sodium-cooled fast reactor, in order to study ultrasonic instrumentation and prepare it installation and utilisation in the sodium of the nuclear reactor. A suitable model has been developed and a set of thermo-hydraulics data has been created, taking account of the particularities of the sodium flow. The results of these simulations are then analysed within the framework of acoustic thermometry, in order to determine which disturbance must be taken into account for the correct operation of the temperature measurement.

  5. Interaction Between Trace Metals, Sodium and Sorbents in Combustion.

    SciTech Connect (OSTI)

    Wendt, O.L.; Davis, S.

    1997-10-17T23:59:59.000Z

    The proposed research is directed at an understanding of how to exploit interactions between sodium, toxic metals and sorbents, in order to optimize sorbents injection procedures, which can be used to capture and transform these metals into environmentally benign forms. The research will use a 17kW downflow, laboratory combustor, to yield data that can be interpreted in terms of fundamental kinetic mechanisms. Metals to be considered are lead, cadmium, and arsenic. Sorbents will be kaolinite, bauxite, and limestone. The role of sulfur will also be determined.

  6. Practical features of illumination with high pressure sodium lamps

    SciTech Connect (OSTI)

    Corth, R.

    1983-06-01T23:59:59.000Z

    A number of concerns raised about the health effects of high pressure sodium lamps (HPS) are discussed. The notion of a ''natural'' human photic environment based on sunlight is disputed. Humans are better adapted to the ''greenish'' spectral composition of forest light than to direct sunlight. It is ironic that the artificial light source which has received the most disapproval, cool white flourescent lamp, has a spectral composition similar to that of forest light. HPS is also available in a full range of colors. Some successful examples of HPS--from North Division High School, in Milwaukee, Wisconsin, to museum exhibits at National Geographic in Washington--are listed.

  7. DRESDYN - A new facility for MHD experiments with liquid sodium

    E-Print Network [OSTI]

    Stefani, F; Gerbeth, G; Giesecke, A; Gundrum, Th; Steglich, C; Weier, T; Wustmann, B

    2012-01-01T23:59:59.000Z

    The DREsden Sodium facility for DYNamo and thermohydraulic studies (DRESDYN) is intended as a platform both for large scale experiments related to geo- and astrophysics as well as for experiments related to thermohydraulic and safety aspects of liquid metal batteries and liquid metal fast reactors. The most ambitious projects in the framework of DRESDYN are a homogeneous hydromagnetic dynamo driven solely by precession and a large Taylor-Couette type experiment for the combined investigation of the magnetorotational instability and the Tayler instability. In this paper we give a short summary about the ongoing preparations and delineate the next steps for the realization of DRESDYN.

  8. Fact Sheet: Sodium-Beta Batteries (October 2012)

    Office of Environmental Management (EM)

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T,OfficeEnd ofEvaluations in Covered Facilities |List ofSodium-Beta Batteries

  9. Sodium hypochlorite Market Trends | OpenEI Community

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit with form HistoryRistmaSinosteel CorporationSocovoltaic Systems JumpSodium

  10. Safe and Effective Deactivation of Metallic Sodium Filled Scrap and Cold Traps From Sodium-cooled Nuclear Reactor D and D - 12176

    SciTech Connect (OSTI)

    Nester, Dean [CH2M HILL Plateau Remediation Company - CHPRC (United States); Crocker, Ben [Commodore Advanced Sciences, Inc. (United States); Smart, Bill [IMPACT Services, Inc. (United States)

    2012-07-01T23:59:59.000Z

    As part of the Plateau Remediation Project at US Department of Energy's Hanford, Washington site, CH2M Hill Plateau Remediation Company (CHPRC) contracted with IMPACT Services, LLC to receive and deactivate approximately 28 cubic meters of sodium metal contaminated debris from two sodium-cooled research reactors (Enrico Fermi Unit 1 and the Fast Flux Test Facility) which had been stored at Hanford for over 25 years. CHPRC found an off-site team composed of IMPACT Services and Commodore Advanced Sciences, Inc., with the facilities and technological capabilities to safely and effectively perform deactivation of this sodium metal contaminated debris. IMPACT Services provided the licensed fixed facility and the logistical support required to receive, store, and manage the waste materials before treatment, and the characterization, manifesting, and return shipping of the cleaned material after treatment. They also provided a recycle outlet for the liquid sodium hydroxide byproduct resulting from removal of the sodium from reactor parts. Commodore Advanced Sciences, Inc. mobilized their patented AMANDA unit to the IMPACT Services site and operated the unit to perform the sodium removal process. Approximately 816 Kg of metallic sodium were removed and converted to sodium hydroxide, and the project was accomplished in 107 days, from receipt of the first shipment at the IMPACT Services facility to the last outgoing shipment of deactivated scrap metal. There were no safety incidents of any kind during the performance of this project. The AMANDA process has been demonstrated in this project to be both safe and effective for deactivation of sodium and NaK. It has also been used in other venues to treat other highly reactive alkali metals, such as lithium (Li), potassium (K), NaK and Cesium (Cs). (authors)

  11. Effect of Sodium on the Catalytic Properties of VOx/CeO2 Catalysts...

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

    dehydrogenation (ODH) of methanol. The effect of sodium on the surface structure, redox properties, and surface aciditybasicity of VOxCeO2 was investigated using hydrogen...

  12. EIS-0306: Treatment and Management of Sodium-Bonded Spent Nuclear Fuel

    Broader source: Energy.gov [DOE]

    DOE prepared a EIS that evaluated the potential environmental impacts of treatment and management of DOE-owned sodium bonded spent nuclear fuel.

  13. Sodium fast reactor safety and licensing research plan. Volume I.

    SciTech Connect (OSTI)

    Sofu, Tanju (Argonne National Laboratory, Argonne, IL); LaChance, Jeffrey L.; Bari, R. (Brokhaven National Laboratory Upton, NY); Wigeland, Roald (Idaho National Laboratory, Idaho Falls, ID); Denman, Matthew R.; Flanagan, George F. (Oak Ridge National Laboratory, Oak Ridge, TN)

    2012-05-01T23:59:59.000Z

    This report proposes potential research priorities for the Department of Energy (DOE) with the intent of improving the licensability of the Sodium Fast Reactor (SFR). In support of this project, five panels were tasked with identifying potential safety-related gaps in available information, data, and models needed to support the licensing of a SFR. The areas examined were sodium technology, accident sequences and initiators, source term characterization, codes and methods, and fuels and materials. It is the intent of this report to utilize a structured and transparent process that incorporates feedback from all interested stakeholders to suggest future funding priorities for the SFR research and development. While numerous gaps were identified, two cross-cutting gaps related to knowledge preservation were agreed upon by all panels and should be addressed in the near future. The first gap is a need to re-evaluate the current procedures for removing the Applied Technology designation from old documents. The second cross-cutting gap is the need for a robust Knowledge Management and Preservation system in all SFR research areas. Closure of these and the other identified gaps will require both a reprioritization of funding within DOE as well as a re-evaluation of existing bureaucratic procedures within the DOE associated with Applied Technology and Knowledge Management.

  14. REACTIONS OF SODIUM PEROXIDE WITH COMPONENTS OF LEGACY PLUTONIUM MATERIALS

    SciTech Connect (OSTI)

    Pierce, R.; Missimer, D.; Crowder, M.

    2011-10-04T23:59:59.000Z

    Plutonium oxide (PuO{sub 2}) calcined at >900 C resists dissolution in nitric acid (HNO{sub 3})-potassium fluoride (KF) solutions, a common method for their dissolution. The Savannah River National Laboratory (SRNL) has developed an alternate method for large samples of PuO{sub 2}-bearing materials using sodium peroxide (Na{sub 2}O{sub 2}) fusion as a pretreatment. The products of the reaction between Na{sub 2}O{sub 2} and PuO{sub 2} have been reported in the literature. As part of the SRNL development effort, additional data about the reaction between Na{sub 2}O{sub 2} and PuO{sub 2} were required. Also needed were data concerning the reaction of Na{sub 2}O{sub 2} with other components that may be present in the feed materials. Sodium peroxide was reacted with aluminum metal (Al), beryllium metal (Be), graphite, potassium chloride (KCl), magnesium chloride (MgCl{sub 2}), and calcium chloride (CaCl{sub 2}). The paper reports and discusses the reaction products of these and related compounds with Na{sub 2}O{sub 2}.

  15. Selection of materials for sodium fast reactor steam generators

    SciTech Connect (OSTI)

    Dubiez-Le Goff, S.; Garnier, S.; Gelineau, O. [AREVA (France); Dalle, F. [Commissariat a l'energie atomique et aux energies alternatives - CEA (France); Blat-Yrieix, M.; Augem, J. M. [Electricite de France - EDF (France)

    2012-07-01T23:59:59.000Z

    Sodium Fast Reactor (SFR) is considered in France as the most mature technology of the different Generation IV systems. In the short-term the designing work is focused on the identification of the potential tracks to demonstrate licensing capability, availability, in-service inspection capability and economical performance. In that frame materials selection for the major components, as the steam generator, is a particularly key point managed within a French Research and Development program launched by AREVA, CEA and EDF. The choice of the material for the steam generator is indeed complex because various aspects shall be considered like mechanical and thermal properties at high temperature, interaction with sodium on one side and water and steam on the other side, resistance to wastage, procurement, fabrication, weldability and ability for inspection and in-situ intervention. The following relevant options are evaluated: the modified 9Cr1Mo ferritic-martensitic grade and the Alloy 800 austenitic grade. The objective of this paper is to assess for both candidates their abilities to reach the current SFR needs regarding material design data, from AFCEN RCC-MRx Code in particular, compatibility with environments and manufacturability. (authors)

  16. Performance-based approach to evaluate alkali-silica reaction potential of aggregate and concrete using dilatometer method 

    E-Print Network [OSTI]

    Shon, Chang Seon

    2009-05-15T23:59:59.000Z

    The undesirable expansion of concrete because of a reaction between alkalis and certain type of reactive siliceous aggregates, known as alkali-silica reactivity (ASR), continues to be a major problem across the entire ...

  17. Visible Light Absorption of Binuclear TiOCoII Charge-Transfer Unit Assembled in Mesoporous Silica

    E-Print Network [OSTI]

    Han, Hongxian; Frei, Heinz

    2008-01-01T23:59:59.000Z

    Ti-MCM-41 silica in acetonitrile solution affords binucleardirectly dissolved in acetonitrile (50 mL) in a Schlenk tubeupon dissolving CoCl 2 in acetonitrile is believed to be the

  18. SnO{sub 2} nanoparticles in silica: Nanosized tools for femtosecond-laser machining of refractive index patterns

    SciTech Connect (OSTI)

    Paleari, A.; Franchina, E.; Chiodini, N.; Lauria, A.; Bricchi, E.; Kazansky, P.G. [CNISM and Dipartimento di Scienza dei Materiali, Universita di Milano-Bicocca, via Cozzi 53, I-20125 Milan (Italy); Optoelectronics Research Centre, University of Southampton, Southampton SO17 1BJ (United Kingdom)

    2006-03-27T23:59:59.000Z

    We show that SnO{sub 2} nanoclusters in silica interact with ultrashort infrared laser pulses focused inside the material generating a hydrostatic compression and photoelastic response of the surrounding glass. This effect, together with the laser-induced nanocluster amorphization, gives rise to positive or negative refractive-index changes, up to 10{sup -2}, depending on the beam-power density. This result points out a wide tuning of the refractive index patterns obtainable in silica-based optical technology.

  19. The effect of silica gel sampling tube design on the analytical recovery of fluorine ions / by Daniel Howard Anna 

    E-Print Network [OSTI]

    Anna, Daniel Howard

    1991-01-01T23:59:59.000Z

    THE EFFECT OF SILICA GEL SAMPLING TUBE DESIGN ON THE ANALYTICAL RECOVERY OF FLUORINE IONS A Thesis by DANIEL HOWARD ANNA Submitted to the Office of Graduate Studies of Texas ARM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE August 1991 Major Subject: Industrial Hygiene THE EFFECI' OF SILICA GEL SAMPLING TUBE DESIGN ON THE ANALYTICAL RECOVERY OF FLUORINE IONS A Thesis by DANIEL HOWARD ANNA Approved as to style and content by: Ri rd B. n...

  20. The effect of silica gel sampling tube design on the analytical recovery of fluorine ions / by Daniel Howard Anna

    E-Print Network [OSTI]

    Anna, Daniel Howard

    1991-01-01T23:59:59.000Z

    THE EFFECT OF SILICA GEL SAMPLING TUBE DESIGN ON THE ANALYTICAL RECOVERY OF FLUORINE IONS A Thesis by DANIEL HOWARD ANNA Submitted to the Office of Graduate Studies of Texas ARM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE August 1991 Major Subject: Industrial Hygiene THE EFFECI' OF SILICA GEL SAMPLING TUBE DESIGN ON THE ANALYTICAL RECOVERY OF FLUORINE IONS A Thesis by DANIEL HOWARD ANNA Approved as to style and content by: Ri rd B. n...

  1. Sequential Treatment by Ionizing Radiation and Sodium Arsenite Dramatically Accelerates TRAIL-Mediated Apoptosis of

    E-Print Network [OSTI]

    is critically important in the translocation of death receptor to the cell surface. Moreover, sodium arsenite and further down-regulates cFLIP levels in melanoma cells. We have evaluated the effects of sequentialSequential Treatment by Ionizing Radiation and Sodium Arsenite Dramatically Accelerates TRAIL

  2. Effect of sodium chloride concentration on the heat resistance and recovery of

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Effect of sodium chloride concentration on the heat resistance and recovery of Salmonella inhibitory effect in the recovery media. Keywords : Salmonella typhimurium, Sodium chloride, Heat treatment, but they also generate damaged cells. The ability of heated cells to survive depends on the recovery conditions

  3. Adsorption of Sodium Dodecyl Sulfate on Functionalized Graphene Measured by Conductometric Titration

    E-Print Network [OSTI]

    Aksay, Ilhan A.

    Adsorption of Sodium Dodecyl Sulfate on Functionalized Graphene Measured by Conductometric States ABSTRACT: We report on the adsorption of sodium dodecyl sulfate (SDS) onto functionalized graphene-to- oxygen ratio of 18, monolayer adsorption of SDS on FGS reaches full surface coverage by 12 M SDS

  4. Challenges and Innovative Technologies On Fuel Handling Systems for Future Sodium-Cooled Fast Reactors

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , AREVA, and EDF have an extensive experience and significant expertise in sodium-cooled fast reactorsChallenges and Innovative Technologies On Fuel Handling Systems for Future Sodium-Cooled Fast Reactors Mathieu CHASSIGNET1;Ã , Sebastien DUMAS1 , Christophe PENIGOT1 , Ge´rard PRELE2 , Alain CAPITAINE2

  5. 4June2013 Page 1 of 8 Sodium Hydroxide (Pellets) SOP Standard Operating Procedures

    E-Print Network [OSTI]

    Cohen, Ronald C.

    4June2013 Page 1 of 8 Sodium Hydroxide (Pellets) SOP Standard Operating Procedures Strong Corrosives ­ Strong Bases (SB) Sodium Hydroxide (Pellets) PrintOH Form: pellets Color: white Melting point/freezing point: 318 °C (604 °F

  6. Volume 33, number 2 OPTICS COMMUNICATIONS May 1980 THE PROCESS OF ENERGY TRANSFER BETWEENEXCITED SODIUM ATOMS

    E-Print Network [OSTI]

    Stroud Jr., Carlos R.

    Volume 33, number 2 OPTICS COMMUNICATIONS May 1980 THE PROCESS OF ENERGY TRANSFER BETWEENEXCITED SODIUM ATOMS J. KRASINSKI, T. STACEWICZ Institute of Experimental Physics WarsawUniversity, 00681 Warsaw,Poland(nX) denotes the sodium atom in one of the higher excited states. The energy difference AE is supplied

  7. Silica aerogel for capturing intact interplanetary dust particles for the Tanpopo experiment

    E-Print Network [OSTI]

    Tabata, Makoto; Kawai, Hideyuki; Imai, Eiichi; Kawaguchi, Yuko; Hashimoto, Hirofumi; Yamagishi, Akihiko

    2015-01-01T23:59:59.000Z

    In this paper, we report the progress in developing a silica-aerogel-based cosmic dust capture panel for use in the Tanpopo experiment on the International Space Station (ISS). Previous studies revealed that ultralow-density silica aerogel tiles comprising two layers with densities of 0.01 and 0.03 g/cm$^3$ developed using our production technique were suitable for achieving the scientific objectives of the astrobiological mission. A special density configuration (i.e., box framing) aerogel with a holder was designed to construct the capture panels. Qualification tests for an engineering model of the capture panel as an instrument aboard the ISS were successful. Sixty box-framing aerogel tiles were manufactured in a contamination-controlled environment.

  8. Experimental stress–strain analysis of tapered silica optical fibers with nanofiber waist

    SciTech Connect (OSTI)

    Holleis, S.; Hoinkes, T.; Wuttke, C.; Schneeweiss, P.; Rauschenbeutel, A. [Vienna Center for Quantum Science and Technology, TU Wien—Atominstitut, Stadionallee 2, 1020 Vienna (Austria)

    2014-04-21T23:59:59.000Z

    We experimentally determine tensile force–elongation diagrams of tapered optical fibers with a nanofiber waist. The tapered optical fibers are produced from standard silica optical fibers using a heat and pull process. Both, the force–elongation data and scanning electron microscope images of the rupture points indicate a brittle material. Despite the small waist radii of only a few hundred nanometers, our experimental data can be fully explained by a nonlinear stress–strain model that relies on material properties of macroscopic silica optical fibers. This is an important asset when it comes to designing miniaturized optical elements as one can rely on the well-founded material characteristics of standard optical fibers. Based on this understanding, we demonstrate a simple and non-destructive technique that allows us to determine the waist radius of the tapered optical fiber. We find excellent agreement with independent scanning electron microscope measurements of the waist radius.

  9. Silica-Like Sequence of Anomalies in Core-Softened Systems

    E-Print Network [OSTI]

    Yu. D. Fomin; E. N. Tsiok; V. N. Ryzhov

    2013-01-17T23:59:59.000Z

    In this paper we present a simulation study of density, structural and diffusion anomalies in core-softened system introduced in our previous publications. It is well-known, that with appropriate parametrization, core-softened systems are remarkable model liquids that exhibit anomalous properties observed in tetrahedral liquids such as silica and water. It is widely believed that core-softened potentials demonstrate the water-like sequence of anomalies. We show that with increasing the depth of the attractive part of the potential the order of the region of anomalous diffusion and the regions of density and structural anomalies is inverted and have the silica-like sequence. We also show that the slope of the Widom line is negative like in water.

  10. Study of a Threshold Cherenkov Counter Based on Silica Aerogels with Low Refractive Indices ?

    E-Print Network [OSTI]

    I. Adachi; T. Sumiyoshi; K. Hayashi; N. Iida; R. Enomoto; K. Tsukada; R. Suda; S. Matsumoto; K. Natori; M. Yokoyama; H. Yokogawa

    1994-01-01T23:59:59.000Z

    To identify ? ± and K ± in the region of 1.0 ? 2.5 GeV/c, a threshold Cherenkov counter equipped with silica aerogels has been investigated. Silica aerogels with a low refractive index of 1.013 have been successfully produced using a new technique. By making use of these aerogels as radiators, we have constructed a Cherenkov counter and have checked its properties in a test beam. The obtained results have demonstrated that our aerogel was transparent enough to make up for loss of the Cherenkov photon yield due to a low refractive index. Various configurations for the photon collection system and some types of photomultipliers, such as the fine-mesh type, for a read out were also tested. From these studies, our design of a Cherenkov counter dedicated to ?/K separation up to a few GeV/c with an efficiency greater than 90 % was considered. 1

  11. High-Q silica zipper cavity for optical radiation pressure driven MOMS switch

    SciTech Connect (OSTI)

    Tetsumoto, Tomohiro; Tanabe, Takasumi, E-mail: takasumi@elec.keio.ac.jp [Department of Electronics and Electrical Engineering, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi Kohoku, Yokohama 223-8522 (Japan)

    2014-07-15T23:59:59.000Z

    We design a silica zipper cavity that has high optical and mechanical Q (quality factor) values and demonstrate numerically the feasibility of a radiation pressure driven micro opto-mechanical system (MOMS) directional switch. The silica zipper cavity has an optical Q of 4.0 × 10{sup 4} and an effective mode volume V{sub mode} of 0.67?{sup 3} when the gap between two cavities is 34 nm. The mechanical Q (Q{sub m}) is determined by thermo-elastic damping and is 2.0 × 10{sup 6} in a vacuum at room temperature. The opto-mechanical coupling rate g{sub OM} is as high as 100 GHz/nm, which allows us to move the directional cavity-waveguide system and switch 1550-nm light with 770-nm light by controlling the radiation pressure.

  12. Sodium fast reactor fuels and materials : research needs.

    SciTech Connect (OSTI)

    Denman, Matthew R.; Porter, Douglas (Idaho National Laboratory, Idaho Falls, ID); Wright, Art (Argonne National Laboratory Argonne, IL); Lambert, John (Argonne National Laboratory Argonne, IL); Hayes, Steven (Idaho National Laboratory, Idaho Falls, ID); Natesan, Ken (Argonne National Laboratory Argonne, IL); Ott, Larry J. (Oak Ridge National Laboratory, Oak Ridge, TN); Garner, Frank (Radiation Effects Consulting. Richland, WA); Walters, Leon (Advanced Reactor Concepts, Idaho Falls, ID); Yacout, Abdellatif (Argonne National Laboratory Argonne, IL)

    2011-09-01T23:59:59.000Z

    An expert panel was assembled to identify gaps in fuels and materials research prior to licensing sodium cooled fast reactor (SFR) design. The expert panel considered both metal and oxide fuels, various cladding and duct materials, structural materials, fuel performance codes, fabrication capability and records, and transient behavior of fuel types. A methodology was developed to rate the relative importance of phenomena and properties both as to importance to a regulatory body and the maturity of the technology base. The technology base for fuels and cladding was divided into three regimes: information of high maturity under conservative operating conditions, information of low maturity under more aggressive operating conditions, and future design expectations where meager data exist.

  13. Sodium-Bearing Waste Treatment Alternatives Implementation Study

    SciTech Connect (OSTI)

    Charles M. Barnes; James B. Bosley; Clifford W. Olsen

    2004-07-01T23:59:59.000Z

    The purpose of this document is to discuss issues related to the implementation of each of the five down-selected INEEL/INTEC radioactive liquid waste (sodium-bearing waste - SBW) treatment alternatives and summarize information in three main areas of concern: process/technical, environmental permitting, and schedule. Major implementation options for each treatment alternative are also identified and briefly discussed. This report may touch upon, but purposely does not address in detail, issues that are programmatic in nature. Examples of these include how the SBW will be classified with respect to the Nuclear Waste Policy Act (NWPA), status of Waste Isolation Pilot Plant (WIPP) permits and waste storage availability, available funding for implementation, stakeholder issues, and State of Idaho Settlement Agreement milestones. It is assumed in this report that the SBW would be classified as a transuranic (TRU) waste suitable for disposal at WIPP, located in New Mexico, after appropriate treatment to meet transportation requirements and waste acceptance criteria (WAC).

  14. Feasibility Study for Vitrification of Sodium-Bearing Waste

    SciTech Connect (OSTI)

    J. J. Quigley; B. D. Raivo; S. O. Bates; S. M. Berry; D. N. Nishioka; P. J. Bunnell

    2000-09-01T23:59:59.000Z

    Treatment of sodium-bearing waste (SBW) at the Idaho Nuclear Technology and Engineering Center (INTEC) within the Idaho National Engineering and Environmental Laboratory is mandated under a Settlement Agreement between the Department of Energy and the State of Idaho. One of the requirements of the Settlement Agreement is the complete calcination (i.e., treatment) of all SBW by December 31, 2012. One of the proposed options for treatment of SBW is vitrification. This study will examine the viability of SBW vitrification. This study describes the process and facilities to treat the SBW, from beginning waste input from INTEC Tank Farm to the final waste forms. Schedules and cost estimates for construction and operation of a Vitrification Facility are included. The study includes a facility layout with drawings, process description and flow diagrams, and preliminary equipment requirements and layouts.

  15. Some aspects of materials development for sodium heated steam generators

    SciTech Connect (OSTI)

    Roy, P.; Spalaris, C.N.

    1980-10-01T23:59:59.000Z

    A development program was undertaken to support the materials selection for steam generator piping and IHX which are to be used in Liquid Metal Fast Breeder Reactors (LMFBR). Four major topics were reviewed, describing the results obtained as well as the direction of future tests. These topics are: carbon transport in sodium, effect of carbon loss/gain upon materials in the reactor Intermediate Heat Transport System (IHTS), corrosion fatigue and aqueous corrosion. The results support the initial assumptions made in specifying the use of 2-1/4Cr-1Mo as the construction material for the evaporator and superheater and Type 316 piping of the IHT system. Future direction of the experimental programs is to further verify the materials choice and to also obtain information which will be essential during the plant installation, operation and reliability of the components.

  16. Hybrid sodium heat pipe receivers for dish/Stirling systems

    SciTech Connect (OSTI)

    Laing, D.; Reusch, M. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V., Stuttgart (Germany). Inst. fuer Technische Thermodynamik

    1997-12-31T23:59:59.000Z

    The design of a hybrid solar/gas heat pipe receiver for the SBP 9 kW dish/Stirling system using a United Stirling AB V160 Stirling engine and the results of on-sun testing in alternative and parallel mode will be reported. The receiver is designed to transfer a thermal power of 35 kW. The heat pipe operates at around 800 C, working fluid is sodium. Operational options are solar-only, gas augmented and gas-only mode. Also the design of a second generation hybrid heat pipe receiver currently developed under a EU-funded project, based on the experience gained with the first hybrid receiver, will be reported. This receiver is designed for the improved SPB/L. and C.-10 kW dish/Stirling system with the reworked SOLO V161 Stirling engine.

  17. Silica coated magnetite nanoparticles for removal of heavy metal ions from polluted waters

    E-Print Network [OSTI]

    Dash, Monika

    2013-01-01T23:59:59.000Z

    Magnetic removal of Hg2+ and other heavy metal ions like Cd2+, Pb2+ etc. using silica coated magnetite particles from polluted waters is a current topic of active research to provide efficient water recycling and long term high quality water. The technique used to study the bonding characteristics of such kind of nanoparticles with the heavy metal ions is a very sensitive hyperfine specroscopy technique called the perturbed angular correlation technique (PAC).

  18. Frequency and surface dependence of the mechanical loss in fused silica

    E-Print Network [OSTI]

    Steven D. Penn; Alexander Ageev; Dan Busby; Gregory M. Harry; Andri M. Gretarsson; Kenji Numata; Phil Willems

    2005-07-23T23:59:59.000Z

    We have compiled measurements of the mechanical loss in fused silica from samples spanning a wide range of geometries and resonant frequency in order to model the known variation of the loss with frequency and surface-to-volume ratio. This improved understanding of the mechanical loss has contributed significantly to the design of advanced interferometric gravitational wave detectors, which require ultra-low loss materials for their test mass mirrors.

  19. A New Concept for the Fabrication of Hydrogen Selective Silica Membranes

    SciTech Connect (OSTI)

    Michael Tsapatsis

    2006-07-31T23:59:59.000Z

    We are attempting to fabricate H{sub 2}-selective silica-based films by ''layer-by-layer'' deposition as a new approach for thin films. A sonication-assisted deposition method was mainly used for ''layer-by-layer'' deposition. In addition, other approaches such as a dip-coating and the use of a polymer matrix with a layered silicate were contrived as well. This report shows the progress done during the 2nd Year of this award.

  20. Effects from Alkali-Silica Reacton and Delayed Ettringite Formation on Reinforced Concrete Column Lap Splices

    E-Print Network [OSTI]

    Eck, Mary

    2012-07-16T23:59:59.000Z

    EFFECTS FROM ALKALI-SILICA REACTION AND DELAYED ETTRINGITE FORMATION ON REINFORCED CONCRETE COLUMN LAP SPLICES A Thesis by MARY KATHLEEN ECK Submitted to the Office of Graduate Studies of Texas A&M University in partial... by MARY KATHLEEN ECK 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 of Committee, Joseph M. Bracci Committee Members...

  1. Structural Assessment of D-Regions Affected by Alkali-Silica Reaction/Delayed Ettringite Formation

    E-Print Network [OSTI]

    Liu, Shih-Hsiang 1979-

    2012-11-12T23:59:59.000Z

    STRUCTURAL ASSESSMENT OF D-REGIONS AFFECTED BY ALKALI- SILICA REACTION/DELAYED ETTRINGITE FORMATION A Dissertation by SHIH-HSIANG LIU Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of Committee, Joseph M. Bracci Committee Members, John B. Mander Stefan Hurlebaus Harry A. Hogan Head of Department, John M. Niedzwecki December 2012 Major Subject: Civil...

  2. Influence of phosphate and silica on U(VI) precipitation from acidic and neutralized wastewaters

    SciTech Connect (OSTI)

    Kanematsu, Masakazu; Perdrial, Nicolas; Um, Wooyong; Chorover, Jon; O'Day, Peggy A.

    2014-04-22T23:59:59.000Z

    Uranium speciation and physical-chemical characteristics were studied in solids precipitated from synthetic acidic to circumneutral wastewaters in the presence and absence of dissolved silica and phosphate to examine thermodynamic and kinetic controls on phase formation. Composition of synthetic wastewater was based on disposal sites 216-U-8 and 216-U-12 Cribs at the Hanford site (WA, USA). In the absence of dissolved silica or phosphate, crystalline or amorphous uranyl oxide hydrates, either compreignacite or meta-schoepite, precipitated at pH 5 or 7 after 30 d of reaction, in agreement with thermodynamic calculations. In the presence of 1 mM dissolved silica representative of groundwater concentrations, amorphous phases dominated by compreignacite precipitated rapidly at pH 5 or 7 as a metastable phase and formation of poorly-crystalline boltwoodite, the thermodynamically stable uranyl silicate phase, was slow. In the presence of phosphate (3 mM), meta-ankoleite initially precipitated as the primary phase at pH 3, 5, or 7 regardless of the presence of 1 mM dissolved silica. Analysis of precipitates by U LIII-edge EXAFS indicated that “autunite-type” sheets of meta-ankoleite transformed to “phosphuranylite-type” sheets after 30 d of reaction, probably due to Ca substitution in the structure. Low solubility of uranyl phosphate phases limits dissolved U(VI) concentrations but differences in particle size, crystallinity, and precipitate composition vary with pH and base cation concentration, which will influence the thermodynamic and kinetic stability of these phases.

  3. Sulfate Fining Chemistry in Oxidized and Reduced Soda-Lime-Silica Glasses

    SciTech Connect (OSTI)

    Matyas, Josef; Hrma, Pavel R.

    2005-05-13T23:59:59.000Z

    Various reducing agents were used and their additions were varied to (1) increase glass quality through eliminating defects from silica scum, (2) decrease SOx emissions through changing the kind and quantity of reducing agents, and (3) improve production efficiency through increased flexibility of glass redox control during continuous processing. The work included measuring silica sand dissolution and sulfate decomposition in melts from glass batches. Glass batches were heated at a temperature-increase rate deemed similar to that experienced in the melting furnace. The sulfate decomposition kinetics was investigated with thermogravimetric analysis-differential thermal analysis and evolved gas analysis. Sulfur concentrations in glasses quenched at different temperatures were determined using X-ray fluorescence spectroscopy. The distribution of residual sand (that which was not dissolved during the initial batch reactions) in the glass was obtained as a function of temperature with optical microscopy in thin-sections of melts. The fraction of undissolved sand was measured with X-ray diffraction. The results of the present study helped Visteon Inc. reduce the energy consumption and establish the batch containing 0.118 mass% of graphite as the best candidate for Visteon glass production. The improved glass batch has a lower potential for silica scum formation and for brown fault occurrence in the final glass product. It was established that bubbles trapped in the melt even at 1450 C have a high probability to be refined when reaching the hot zone in the glass furnace. Furthermore, silica sand does not accumulate at the glass surface and dissolves faster in the batch with graphite than in the batch with carbocite.

  4. Silica and acid-detergent fiber content of five varieties of bermudagrass

    E-Print Network [OSTI]

    Jungman, Frederick Michael

    1971-01-01T23:59:59.000Z

    of digestibility. This fraction contains residual ash, one component of which is silica, plus lignin and cellulose. Lignin is an indigestible substance with a complex structure containing carbon, hydrogen, oxygen, and a poly- hydroxy aromatic compound as a... nucleus (12). Lignin reduces the digestibility of many plants. Theories as to how lignin affects digestibility include encrustation by lignin, a lignin carbohydrate compound as such, or hydrogen bonded molecular complexes (20). It is possible...

  5. Origins of secondary silica within Yucca Mountain, Nye County, southwestern Nevada

    SciTech Connect (OSTI)

    Moscati, R.J.; Whelan, J.F.

    1996-09-01T23:59:59.000Z

    The accuracy of predictions of the hydrologic response of Yucca Mountain to future climate depends largely on how well relations between past climate and hydrology can be resolved. To advance this reconstruction, secondary minerals in and near Yucca Mountain, deposited by ground waters that originated both as surficial recharge at Yucca Mountain and from regional aquifers, are being studied to determine past ground-water sources and chemistries. Preliminary data on stable oxygen isotopes indicate that, although silica (opal, quartz, and chalcedony) and calcite and have formed in similar settings and from somewhat similar fluids, the authors have found no compelling evidence of coprecipitation or formation from identical fluids. If verified by further analyses, this precludes the use of silica-calcite mineral pairs for precise geothermometry. The preliminary data also indicate that opal and calcite occurrences in pedogenic and unsaturated-zone settings are invariably compatible with formation under modern ambient surface or subsurface temperatures. Silica and calcite stable-isotope studies are being integrated with soil geochemical modeling. This modeling will define the soil geochemical condition (climate) leading to opal or calcite deposition and to the transfer functions that may apply at the meteorologic soil unsaturated-zone interfaces. Additional study of pedogenic and unsaturated-zone silica is needed to support these models. The hypothesis that the transformation of vapor-phase tridymite to quartz requires saturated conditions is being tested through stable oxygen-isotope studies of lithophysal tridymite/quartz mixtures. Should this hypothesis be verified, mineralogic analysis by X-ray diffraction theoretically would permit reconstruction of past maximum water-table elevations.

  6. Impact of Sodium Layer variations on the performance of the E-ELT MCAO module

    E-Print Network [OSTI]

    Schreiber, L; Arcidiacono, C; Pfrommer, T; Holzlöhner, R; Lombini, M; Hickson, P

    2015-01-01T23:59:59.000Z

    Multi-Conjugate Adaptive Optics systems based on sodium Laser Guide Stars may exploit Natural Guide Stars to solve intrinsic limitations of artificial beacons (tip-tilt indetermination and anisoplanatism) and to mitigate the impact of the sodium layer structure and variability. The sodium layer may also have transverse structures leading to differential effects among Laser Guide Stars. Starting from the analysis of the input perturbations related to the Sodium Layer variability, modeled directly on measured sodium layer profiles, we analyze, through a simplified end-to-end simulation code, the impact of the low/medium orders induced on global performance of the European Extremely Large Telescope Multi-Conjugate Adaptive Optics module MAORY.

  7. Sodium Heat Engine Development Program. Phase 1, Final report

    SciTech Connect (OSTI)

    Singh, J.P.; Kupperman, D.S.; Majumdar, S.; Dorris, S.; Gopalsami, N.; Dieckman, S.L.; Jaross, R.A.; Johnson, D.L.; Gregar, J.S.; Poeppel, R.B.; Raptis, A.C.; Valentin, R.A.

    1992-01-01T23:59:59.000Z

    The Sodium Heat Engine (SHE) is an efficient thermoelectric conversion device which directly generates electricity from a thermally regenerative electrochemical cell that relies on the unique conduction properties of {beta}{double_prime}-alumina solid electrolyte (BASE). Laboratory models of a variety of SHE devices have demonstrated the feasibility and efficiency of the system, engineering development of large prototype devices has been slowed by a series of materials and fabrication problems. Failure of the electrolyte tubes has been a recurring problem and a number of possible causes have been postulated. To address these issues, a two-phase engineering development program was undertaken. This report summarizes the final results of the first phase of the program, which included extensive materials characterization activities, a study of applicable nondestructive evaluation methods, an investigation of possible stress states that would contribute to fracture, and certain operational issues associated with the electromagnetic pumps used in the SHE prototype. Mechanical and microstructural evaluation of commercially obtained BASE tubes revealed that they should be adequate for SHE applications and that sodium exposure produced no appreciable deleterious strength effects. Processing activities to produce a more uniform and smaller grain size for the BASE tubes were completed using isostatic pressing, extrusion, and slip casting. Green tubes were sintered by conventional and microwave plasma methods. Of particular interest is the residual stress state in the BASE tubes, and both analysis and nondestructive evaluation methods were employed to evaluate these stresses. X-ray and neutron diffraction experiments were performed to determine the bulk residual stresses in commercially fabricated BASE tubes; however, tube-to-tube variations and variations among the various methods employed did not allow formulation of a definitive definition of the as-fabricated stress state.

  8. 105-DR Large Sodium Fire Facility closure plan. Revision 1

    SciTech Connect (OSTI)

    Not Available

    1993-05-01T23:59:59.000Z

    The Hanford Site, located northwest of the city of Richland, Washington, houses reactors, chemical-separation systems, and related facilities used for the production of special nuclear materials, and activities associated with nuclear energy development. The 105-DR Large Sodium Fire Facility (LSFF), which was in operation from about 1972 to 1986, was a research laboratory that occupied the former ventilation supply room on the southwest side of the 105-DR Reactor facility. The LSFF was established to provide a means of investigating fire and safety aspects associated with large sodium or other metal alkali fires in the liquid metal fast breeder reactor (LMFBR) facilities. The 105-DR Reactor facility was designed and built in the 1950`s and is located in the 100-D Area of the Hanford Site. The building housed the 105-DR defense reactor, which was shut down in 1964. The LSFF was initially used only for engineering-scale alkali metal reaction studies. In addition, the Fusion Safety Support Studies program sponsored intermediate-size safety reaction tests in the LSFF with lithium and lithium lead compounds. The facility has also been used to store and treat alkali metal waste, therefore the LSFF is subject to the regulatory requirements for the storage and treatment of dangerous waste. Closure will be conducted pursuant to the requirements of the Washington Administrative Code (WAC) 173-303-610. This closure plan presents a description of the facility, the history of waste managed, and the procedures that will be followed to close the LSFF as an Alkali Metal Treatment Facility. No future use of the LSFF is expected.

  9. Coating thickness and coverage effects on the forces between silica nanoparticles in water

    E-Print Network [OSTI]

    K. Michael Salerno; Ahmed E. Ismail; J. Matthew D. Lane; Gary S. Grest

    2014-05-20T23:59:59.000Z

    The structure and interactions of coated silica nanoparticles have been studied in water using molecular dynamics simulations. For 5 nm diameter amorphous silica nanoparticles we studied the effects of varying the chain length and grafting density of polyethylene oxide (PEO) on the nanoparticle coating's shape and on nanoparticle-nanoparticle effective forces. For short ligands of length $n=6$ and $n=20$ repeat units, the coatings are radially symmetric while for longer chains ($n=100$) the coatings are highly anisotropic. This anisotropy appears to be governed primarily by chain length, with coverage playing a secondary role. For the largest chain lengths considered, the strongly anisotropic shape makes fitting to a simple radial force model impossible. For shorter ligands, where the coatings are isotropic, we found that the force between pairs of nanoparticles is purely repulsive and can be fit to the form $(R/2r_\\text{core}-1)^{-b}$ where $R$ is the separation between the center of the nanoparticles, $r_\\text{core}$ is the radius of the silica core, and $b$ is measured to be between 2.3 and 4.1.

  10. Single-Molecule Imaging of DNAs with Sticky Ends at Water/Fused Silica Interface

    SciTech Connect (OSTI)

    Slavica Isailovic

    2005-12-17T23:59:59.000Z

    Total internal reflection fluorescence microscopy (TIRFM) was used to study intermolecular interactions of DNAs with unpaired (sticky) ends of different lengths at water/fused silica interface at the single-molecule level. Evanescent field residence time, linear velocity and adsorption/desorption frequency were measured in a microchannel for individual DNA molecules from T7, Lambda, and PSP3 phages at various pH values. The longest residence times and the highest adsorption/desorption frequencies at the constant flow at pH 5.5 were found for PSP3 DNA, followed by lower values for Lambda DNA, and the lowest values for T7 DNA. Since T7, Lambda, and PSP3 DNA molecules contain none, twelve and nineteen unpaired bases, respectively, it was concluded that the affinity of DNAs for the surface increases with the length of the sticky ends. This confirms that hydrophobic and hydrogen-bonding interactions between sticky ends and fused-silica surface are driving forces for DNA adsorption at the fused-silica surface. Described single-molecule methodology and results therein can be valuable for investigation of interactions in liquid chromatography, as well as for design of DNA hybridization sensors and drug delivery systems.

  11. Controlled epitaxial growth of mesoporous silica/gold nanorod nanolollipops and nanodumb-bells

    SciTech Connect (OSTI)

    Huang, Ching-Mao [Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, 35 Keyan Road, Zhunan Town, Miaoli 35053, Taiwan (China); Material and Chemical Laboratories, Industrial Technology Research Institute, Hsinchu 30011, Taiwan (China); Chung, Ming-Fang; Lo, Leu-Wei, E-mail: lwlo@nhri.org.tw [Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, 35 Keyan Road, Zhunan Town, Miaoli 35053, Taiwan (China); Souris, Jeffrey S. [Department of Radiology, The University of Chicago, Chicago, Illinois 60637 (United States)

    2014-11-01T23:59:59.000Z

    In this work, we describe the controlled synthesis of novel heterogeneous nanostructures comprised of mesoporous silica-coated gold nanorods (MSGNRs) in the form of core–shell nanolollipops and nanodumb-bells, using a seed-mediated sol–gel method. Although MSGNR core–shell (?-MSGNR) structures have been reported previously by us and others, we herein discuss the first ever fabrication of MSGNR nanolollipops (?-MSGNR) and nanodumb-bells (?-MSGNR), achieved by simply controlling the aging time of gold nanorods (GNRs), the residual cetyltrimethylammonium bromide (CTAB) coating of GNRs, and the addition of dimethyl formamide during incubation, centrifugation, and sonication, respectively. Transmission electron microscopy revealed two bare GNR isoforms, with aspect ratios of approximately 4 and 6, while scanning electron microscopy was used to further elucidate the morphology of ?-MSGNR and ?-MSGNR heterostructures. In agreement with the smaller dielectric constants afforded by incomplete silica encasement, spectroscopic studies of ?-MSGNR and ?-MSGNR, surface plasmon resonance (SPR) bands revealed 20-40 nm blue shifts relative to the SPR of ?-MSGNR. On the basis of the attributes and applications of more conventional ?-MSGNRs, ?-MSGNRs and ?-MSGNRs are anticipated to provide most of the utility of ?-MSGNRs, but with the additional functionalities that accompany their incorporation of both bare gold and mesoporous silica encased tips; with significant/unique implications for biomedical and catalytic applications.

  12. Reaction and spectroscopic study of silica-supported molybdenum(IV) and tungsten(IV) dimers

    SciTech Connect (OSTI)

    Sullivan, D.L.; Roark, R.D.; Ekerdt, J.G. [Univ. of Texas, Austin, TX (United States); Deutsch, S.E.; Gates, B.C. [Univ. of California, Davis, CA (United States)

    1995-03-16T23:59:59.000Z

    Cyclopentadienyl molybdenum di- and tricarbonyl dimer and cyclopentadienyl tungsten di- and tricarbonyl dimer complexes were added to silica as precursors to supported metal dimers. These complexes are shown to yield metal dimers following attachment to the silica and carbonyl ligand removal. Reductive carbonyl coupling of acetaldehyde and acetone was used as a molecular probe to determine whether dimers formed, with each metal atom being in the 4+ oxidation state. Acetaldehyde and acetone reductively coupled to produce cis- and trans-2-butenes and 2,3-dimethyl-2-butene, respectively. Diolates formed as intermediate products during the coupling reaction. Infrared bands were observed at 2969, 2925, and 2859 cm-1 that correspond to {nu}{sub asym}(CH{sub 3}), {nu}(CH), and {nu}{sub sym}(CH{sub 3}), respectively, for the 2,3-butanediolate formed from acetaldehyde. The hydrogens on the methyl groups for the acetone reductive coupling intermediate, 2,3-dimethyl-2,3-butanediolate, were not equivalent, resulting in the appearance of three C-H stretching frequencies at 2977, 2939, and 2891 cm{sup {minus}1} that are assigned to A{prime}{sub asym}, A{prime}, A{prime}{sub sym} of CH{sub 3}, respectively. Extended X-ray absorption fine structure (EXAFS) spectroscopy was used to characterize a sample prepared from cyclopentadienyl tungsten dicarbonyl dimer on silica. 74 refs., 7 figs., 5 tabs.

  13. Sol-gel processed silica-alumina materials for diesel engine emission reduction catalysts

    SciTech Connect (OSTI)

    Narula, C.K.; Rokosz, M.; Allard, L.F.; Kudla, R.J.; Chattha, M.S.

    2000-04-18T23:59:59.000Z

    The incorporation of >30% silica in alumina prior to platinum impregnation improves the NOx conversion efficiency in the 200--300 C range from 45 to 57% and reduces light-off temperature. Further increase in the amount of silica to 50% is detrimental to NOx conversion efficiency. The {sup 1}H and {sup 29}Si NMR of the materials suggest that this trend is probably related to the surface acidity. The analyses of these materials by X-ray powder diffraction and electron microscopy do not reveal significant differences. Additional NOx conversion in the 350--450 C range with a maximum of 30% at 400 C can be achieved if a rhodium-impregnated 30% silica-alumina, Rh-30% SiO{sub 2}-Al{sub 2}O{sub 3}, is placed upstream of Pt-30% SiO{sub 2}-Al{sub 2}O{sub 3}. It is important to note that mixing Pt-30% SiO{sub 2}-Al{sub 2}O{sub 3} with Rh-30% SiO{sub 2}-Al{sub 2}O{sub 3} does not enhance conversion efficiency or effective temperature range.

  14. Sodium-Beta Batteries for Grid-Scale Storage: Planar Sodium-Beta Batteries for Renewable Integration and Grid Applications

    SciTech Connect (OSTI)

    None

    2010-02-01T23:59:59.000Z

    Broad Funding Opportunity Announcement Project: EaglePicher is developing a sodium-beta alumina (Na-Beta) battery for grid-scale energy storage. High-temperature Na-Beta batteries are a promising grid-scale energy storage technology, but existing approaches are expensive and unreliable. EaglePicher has modified the shape of the traditional, tubular-shaped Na-Beta battery. It is using an inexpensive stacked design to improve performance at lower temperatures, leading to a less expensive overall storage technology. The new design greatly simplifies the manufacturing process for beta alumina membranes (a key enabling technology), providing a subsequent pathway to the production of scalable, modular batteries at half the cost of the existing tubular designs.

  15. Dendrimer Templated Synthesis of One Nanometer Rh and Pt Particles Supported on Mesoporous Silica: Catalytic Activity for Ethylene and Pyrrole Hydrogenation.

    E-Print Network [OSTI]

    Huang, Wenyu

    2009-01-01T23:59:59.000Z

    Scheme 2) and pyrrole hydrogenation (Scheme 3). Synthesis ofSynthesis of One Nanometer Rh and Pt Particles Supported on Mesoporous Silica: Catalytic Activity for Ethylene and Pyrrole

  16. Environmental, health, and safety issues of sodium-sulfur batteries for electric and hybrid vehicles

    SciTech Connect (OSTI)

    Hammel, C.J.

    1992-09-01T23:59:59.000Z

    This report examines the shipping regulations that govern the shipment of dangerous goods. Since the elemental sodium contained in both sodium-sulfur and sodium-metal-chloride batteries is classified as a dangerous good, and is listed on both the national and international hazardous materials listings, both national and international regulatory processes are considered in this report The interrelationships as well as the differences between the two processes are highlighted. It is important to note that the transport regulatory processes examined in this report are reviewed within the context of assessing the necessary steps needed to provide for the domestic and international transport of sodium-beta batteries. The need for such an assessment was determined by the Shipping Sub-Working Group (SSWG) of the EV Battery Readiness Working Group (Working Group), created in 1990. The Working Group was created to examine the regulatory issues pertaining to in-vehicle safety, shipping, and recycling of sodium-sulfur batteries, each of which is addressed by a sub-working group. The mission of the SSWG is to establish basic provisions that will ensure the safe and efficient transport of sodium-beta batteries. To support that end, a proposal to the UN Committee of Experts was prepared by the SSWG, with the goal of obtaining a proper shipping name and UN number for sodium-beta batteries and to establish the basic transport requirements for such batteries (see the appendix for the proposal as submitted). It is emphasized that because batteries are large articles containing elemental sodium and, in some cases, sulfur, there is no existing UN entry under which they can be classified and for which modal transport requirements, such as the use of packaging appropriate for such large articles, are provided for. It is for this reason that a specific UN entry for sodium-beta batteries is considered essential.

  17. Structure of rhenium-containing sodium borosilicate glass

    SciTech Connect (OSTI)

    Goel, Ashutosh; McCloy, John S.; Windisch, Charles F.; Riley, Brian J.; Schweiger, Michael J.; Rodriguez, Carmen P.; Ferreira, Jose M.

    2013-03-01T23:59:59.000Z

    A series of sodium borosilicate glasses were synthesized with increasing fractions of KReO4 or Re2O7, to 10000 ppm (1 mass%) target Re in glass, to assess the effects of large concentrations of rhenium on glass structure and to estimate the solubility of technetium, a radioactive component in typical low active waste nuclear waste glasses. Magic angle spinning nuclear magnetic resonance (MAS-NMR), Fourier transform infrared (FTIR) spectroscopy, and Raman spectroscopy were performed to characterize the glasses as a function of Re source additions. In general, silicon was found coordinated in a mixture of Q2 and Q3 structural units, while Al was 4-coordinated and B was largely 3-coordinate and partially 4-coordinated. The rhenium source did not appear to have significant effects on the glass structure. Thus, at the up to the concentrations that remain in dissolved in glass, ~3000 ppm Re by mass maximum. , the Re appeared to be neither a glass-former nor a strong glass modifier., Rhenium likely exists in isolated ReO4- anions in the interstices of the glass network, as evidenced by the polarized Raman spectrum of the Re glass in the absence of sulfate. Analogous to SO42-¬ in similar glasses, ReO4- is likely a network modifier and forms alkali salt phases on the surface and in the bulk glass above solubility.

  18. Sodium-bearing Waste Treatment Technology Evaluation Report

    SciTech Connect (OSTI)

    Charles M. Barnes; Arlin L. Olson; Dean D. Taylor

    2004-05-01T23:59:59.000Z

    Sodium-bearing waste (SBW) disposition is one of the U.S. Department of Energy (DOE) Idaho Operation Office’s (NE-ID) and State of Idaho’s top priorities at the Idaho National Engineering and Environmental Laboratory (INEEL). The INEEL has been working over the past several years to identify a treatment technology that meets NE-ID and regulatory treatment requirements, including consideration of stakeholder input. Many studies, including the High-Level Waste and Facilities Disposition Environmental Impact Statement (EIS), have resulted in the identification of five treatment alternatives that form a short list of perhaps the most appropriate technologies for the DOE to select from. The alternatives are (a) calcination with maximum achievable control technology (MACT) upgrade, (b) steam reforming, (c) cesium ion exchange (CsIX) with immobilization, (d) direct evaporation, and (e) vitrification. Each alternative has undergone some degree of applied technical development and preliminary process design over the past four years. This report presents a summary of the applied technology and process design activities performed through February 2004. The SBW issue and the five alternatives are described in Sections 2 and 3, respectively. Details of preliminary process design activities for three of the alternatives (steam reforming, CsIX, and direct evaporation) are presented in three appendices. A recent feasibility study provides the details for calcination. There have been no recent activities performed with regard to vitrification; that section summarizes and references previous work.

  19. Example Work Domain Analysis for a Reference Sodium Fast Reactor

    SciTech Connect (OSTI)

    Hugo, Jacques [Idaho National Lab. (INL), Idaho Falls, ID (United States); Oxstrand, Johanna [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-01-01T23:59:59.000Z

    The nuclear industry is currently designing and building a new generation of reactors that will include different structural, functional, and environmental aspects, all of which are likely to have a significant impact on the way these plants are operated. In order to meet economic and safety objectives, these new reactors will all use advanced technologies to some extent, including new materials and advanced digital instrumentation and control systems. New technologies will affect not only operational strategies, but will also require a new approach to how functions are allocated to humans or machines to ensure optimal performance. Uncertainty about the effect of large scale changes in plant design will remain until sound technical bases are developed for new operational concepts and strategies. Up-to-date models and guidance are required for the development of operational concepts for complex socio-technical systems. This report describes how the classical Work Domain Analysis method was adapted to develop operational concept frameworks for new plants. This adaptation of the method is better able to deal with the uncertainty and incomplete information typical of first-of-a-kind designs. Practical examples are provided of the systematic application of the method in the operational analysis of sodium-cooled reactors. Insights from this application and its utility are reviewed and arguments for the formal adoption of Work Domain Analysis as a value-added part of the Systems Engineering process are presented.

  20. EXTENDING SODIUM FAST REACTOR DRIVER FUEL USE TO HIGHER TEMPERATURES

    SciTech Connect (OSTI)

    Douglas L. Porter

    2011-02-01T23:59:59.000Z

    Calculations of potential sodium-cooled fast reactor fuel temperatures were performed to estimate the effects of increasing the outlet temperature of a given fast reactor design by increasing pin power, decreasing assembly flow, or increasing inlet temperature. Based upon experience in the U.S., both metal and mixed oxide (MOX) fuel types are discussed in terms of potential performance effects created by the increased operating temperatures. Assembly outlet temperatures of 600, 650 and 700 °C were used as goal temperatures. Fuel/cladding chemical interaction (FCCI) and fuel melting, as well as challenges to the mechanical integrity of the cladding material, were identified as the limiting phenomena. For example, starting with a recent 1000 MWth fast reactor design, raising the outlet temperature to 650 °C through pin power increase increased the MOX centerline temperature to more than 3300 °C and the metal fuel peak cladding temperature to more than 700 °C. These exceeded limitations to fuel performance; fuel melting was limiting for MOX and FCCI for metal fuel. Both could be alleviated by design ‘fixes’, such as using a barrier inside the cladding to minimize FCCI in the metal fuel, or using annular fuel in the case of MOX. Both would also require an advanced cladding material with improved stress rupture properties. While some of these are costly, the benefits of having a high-temperature reactor which can support hydrogen production, or other missions requiring high process heat may make the extra costs justified.

  1. Applying risk informed methodologies to improve the economics of sodium-cooled fast reactors

    E-Print Network [OSTI]

    Nitta, Christopher C

    2010-01-01T23:59:59.000Z

    In order to support the increasing demand for clean sustainable electricity production and for nuclear waste management, the Sodium-Cooled Fast Reactor (SFR) is being developed. The main drawback has been its high capital ...

  2. Development of a model to predict flow oscillations in low-flow sodium boiling

    E-Print Network [OSTI]

    Levin, Alan Edward

    1980-01-01T23:59:59.000Z

    An experimental and analytical program has been carried out in order to better understand the cause and effect of flow oscillations in boiling sodium systems. These oscillations have been noted in previous experiments with ...

  3. Chemically Bonded Phosphorus/Graphene Hybrid as a High Performance Anode for Sodium-Ion Batteries

    SciTech Connect (OSTI)

    Song, Jiangxuan; Yu, Zhaoxin; Gordin, Mikhail; Hu, Shilin; Yi, Ran; Tang, Duihai; Walter, Timothy; Regula, Michael; Choi, Daiwon; Li, Xiaolin; Manivannan, Ayyakkannu; Wang, Donghai

    2014-11-12T23:59:59.000Z

    Room temperature sodium-ion batteries are of great interest for high-energy-density energy storage systems because of low-cost, natural abundance of sodium. Here, we report a novel graphene nanosheets-wrapped phosphorus composite as an anode for high performance sodium-ion batteries though a facile ball-milling of red phosphorus and graphene nanosheets. Not only can the graphene nanosheets significantly improve the electrical conductivity, but they also serve as a buffer layer to accommodate the large volume change of phosphorus in the charge-discharge process. As a result, the graphene wrapped phosphorus composite anode delivers a high reversible capacity of 2077 mAh/g with excellent cycling stability (1700 mAh/g after 60 cycles) and high Coulombic efficiency (>98%). This simple synthesis approach and unique nanostructure can potentially extend to other electrode materials with unstable solid electrolyte interphases in sodium-ion batteries.

  4. Tools for supercritical carbon dioxide cycle analysis and the cycle's applicability to sodium fast reactors

    E-Print Network [OSTI]

    Ludington, Alexander R. (Alexander Rockwell)

    2009-01-01T23:59:59.000Z

    The Sodium-Cooled Fast Reactor (SFR) and the Supercritical Carbon Dioxide (S-C0?) Recompression cycle are two technologies that have the potential to impact the power generation landscape of the future. In order for their ...

  5. Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries using Synchrotron Radiation Techniques

    E-Print Network [OSTI]

    Doeff, Marca M.

    2013-01-01T23:59:59.000Z

    Rechargeable Sodium-Ion Batteries: Potential Alternatives toCurrent Lithium-Ion Batteries. Adv. Energy Mater. 2 (2012):J. , Rojo, T. Na-ion Batteries, Recent Advances and Present

  6. The Beta-Neutrino Correlation in Sodium-21 and Other Nuclei

    E-Print Network [OSTI]

    Vetter, Paul A.; Abo-Shaeer, Jamil; Freedman, Stuart J.; Maruyama, Reina

    2008-01-01T23:59:59.000Z

    RIA?INTproc?abetanu THE BETA-NEUTRINO CORRELATION IN SODIUM-electrons shaken off in beta decay. High detection ef?ciencyTOF template spectra for beta decays to 21 Ne + , are shown

  7. Application of the Technology Neutral Framework to Sodium-­Cooled Fast Reactors

    E-Print Network [OSTI]

    Johnson, Brian C.

    Sodium cooled fast reactors (SFRs) are considered as a novel example to exercise the Technology Neutral Framework (TNF) proposed in NUREG-1860. One reason for considering SFRs is that they have historically had a licensing ...

  8. Review of Chemical Processes for the Synthesis of Sodium Borohydride Millennium Cell Inc.

    E-Print Network [OSTI]

    Review of Chemical Processes for the Synthesis of Sodium Borohydride Millennium Cell Inc. Prepared........................................................................................... 6 Methane (or Natural Gas) as Reducing Agent remained the same since it became commercial in the 1950s and is based on synthetic pathways developed

  9. Ultracold molecules from ultracold atoms : interactions in sodium and lithium gas

    E-Print Network [OSTI]

    Christensen, Caleb A

    2011-01-01T23:59:59.000Z

    The thesis presents results from experiments in which ultracold Sodium-6 and Lithium-23 atomic gases were studied near a Feshbach resonance at high magnetic fields. The enhanced interactions between atoms in the presence ...

  10. An Evaluation of the Annular Fuel and Bottle-Shaped Fuel Concepts for Sodium Fast Reactors

    E-Print Network [OSTI]

    Memmott, Matthew

    Two innovative fuel concepts, the internally and externally cooled annular fuel and the bottle-shaped fuel, were investigated with the goal of increasing the power density and reduce the pressure drop in the sodium-cooled ...

  11. Application of the technology neutral framework to sodium cooled fast reactors

    E-Print Network [OSTI]

    Johnson, Brian C. (Brian Carl)

    2010-01-01T23:59:59.000Z

    Sodium cooled fast reactors (SFRs) are considered as a novel example to exercise the Technology Neutral Framework (TNF) proposed in NUREG- 1860. One reason for considering SFRs is that they have historically had a licensing ...

  12. Sodium sulfate heptahydrate: a synchrotron energy-dispersive diffraction study of an elusive metastable hydrated salt 

    E-Print Network [OSTI]

    Hamilton, Andrea; Hall, Christopher

    2008-01-01T23:59:59.000Z

    We describe an unusual application of synchrotron energy-dispersive diffraction with hard X-rays to obtain structural information on metastable sodium sulfate heptahydrate. This hydrate was often mentioned in nineteenth ...

  13. Metal corrosion in a supercritical carbon dioxide - liquid sodium power cycle.

    SciTech Connect (OSTI)

    Moore, Robert Charles; Conboy, Thomas M.

    2012-02-01T23:59:59.000Z

    A liquid sodium cooled fast reactor coupled to a supercritical carbon dioxide Brayton power cycle is a promising combination for the next generation nuclear power production process. For optimum efficiency, a microchannel heat exchanger, constructed by diffusion bonding, can be used for heat transfer from the liquid sodium reactor coolant to the supercritical carbon dioxide. In this work, we have reviewed the literature on corrosion of metals in liquid sodium and carbon dioxide. The main conclusions are (1) pure, dry CO{sub 2} is virtually inert but can be highly corrosive in the presence of even ppm concentrations of water, (2) carburization and decarburization are very significant mechanism for corrosion in liquid sodium especially at high temperature and the mechanism is not well understood, and (3) very little information could be located on corrosion of diffusion bonded metals. Significantly more research is needed in all of these areas.

  14. Thermal-hydraulic analysis of innovative fuel configurations for the sodium fast reactor

    E-Print Network [OSTI]

    Memmott, Matthew J

    2009-01-01T23:59:59.000Z

    The sodium fast reactor (SFR) is currently being reconsidered as an instrument for actinide management throughout the world, thanks in part to international programs such as the Generation-IV and especially the Global ...

  15. Development of an improved sodium exposure test cell experiment for characterization of AMTEC electrode performance 

    E-Print Network [OSTI]

    Fiebig, Bradley Nelson

    1999-01-01T23:59:59.000Z

    An investigation into sources of inconsistencies in sodium exposure test cell (SETC) measurements, used to characterize AMTEC electrode performance, was conducted. Development of modifications to the SETC setup and operation ...

  16. Population strategies to decrease sodium intake : a global cost-effectiveness analysis

    E-Print Network [OSTI]

    Webb, Michael William, S.M. Massachusetts Institute of Technology

    2013-01-01T23:59:59.000Z

    Excessive sodium consumption is both prevalent and very costly in many countries around the world. Recent research has found that more than 90% of the world's adult population live in countries with mean intakes exceeding ...

  17. Process Flow Chart for Immobilizing of Radioactive High Concentration Sodium Hydroxide Product from the Sodium Processing Facility at the BN-350 Nuclear power plant in Aktau, Kazakhstan

    SciTech Connect (OSTI)

    Burkitbayev, M.; Omarova, K.; Tolebayev, T. [Ai-Farabi Kazakh National University, Chemical Faculty, Republic of Kazakhstan (Kazakhstan); Galkin, A. [KATEP Ltd., Republic of Kazakhstan (Kazakhstan); Bachilova, N. [NIISTROMPROEKT Ltd., Republic of Kazakhstan (Kazakhstan); Blynskiy, A. [Nuclear Technology Safety Centre, Republic of Kazakhstan (Kazakhstan); Maev, V. [MAEK-Kazatomprom Ltd., Republic of Kazakhstan (Kazakhstan); Wells, D. [NUKEM Limited- a member of the Freyssinet Group, Winfrith Technology Centre, Dorchester, Dorset (United Kingdom); Herrick, A. [NUKEM Limited- a member of the Freyssinet Group, Caithness (United Kingdom); Michelbacher, J. [Idaho National Laboratory, Idaho Falls (United States)

    2008-07-01T23:59:59.000Z

    This paper describes the results of a joint research investigations carried out by the group of Kazakhstan, British and American specialists in development of a new material for immobilization of radioactive 35% sodium hydroxide solutions from the sodium coolant processing facility of the BN-350 nuclear power plant. The resulting solid matrix product, termed geo-cement stone, is capable of isolating long lived radionuclides from the environment. The physico-mechanical properties of geo-cement stone have been investigated and the flow chart for its production verified in a full scale experiments. (author)

  18. Femtosecond diffraction dynamics of laser-induced periodic surface structures on fused silica

    SciTech Connect (OSTI)

    Hoehm, S.; Rosenfeld, A. [Max-Born-Institut fuer Nichtlineare Optik und Kurzzeitspektroskopie (MBI), Max-Born-Strasse 2A, D-12489 Berlin (Germany)] [Max-Born-Institut fuer Nichtlineare Optik und Kurzzeitspektroskopie (MBI), Max-Born-Strasse 2A, D-12489 Berlin (Germany); Krueger, J.; Bonse, J. [BAM Bundesanstalt fuer Materialforschung und - pruefung, Unter den Eichen 87, D-12205 Berlin (Germany)] [BAM Bundesanstalt fuer Materialforschung und - pruefung, Unter den Eichen 87, D-12205 Berlin (Germany)

    2013-02-04T23:59:59.000Z

    The formation of laser-induced periodic surface structures (LIPSS) on fused silica upon irradiation with linearly polarized fs-laser pulses (50 fs pulse duration, 800 nm center wavelength) is studied experimentally using a transillumination femtosecond time-resolved (0.1 ps-1 ns) pump-probe diffraction approach. This allows to reveal the generation dynamics of near-wavelength-sized LIPSS showing a transient diffraction at specific spatial frequencies even before a corresponding permanent surface relief was observed. The results confirm that the ultrafast energy deposition to the materials surface plays a key role and triggers subsequent physical mechanisms such as carrier scattering into self-trapped excitons.

  19. Mesoporous Silica Nanomaterials for Applications in Catalysis, Sensing, Drug Delivery and Gene Transfection

    SciTech Connect (OSTI)

    Daniela Rodica Radu

    2005-12-19T23:59:59.000Z

    The central theme of this dissertation is represented by the versatility of mesoporous silica nanomaterials in various applications such as catalysis and bio-applications, with main focus on biological applications of Mesoporous Silica Nanospheres (MSN). The metamorphosis that we impose to these materials from catalysis to sensing and to drug and gene delivery is detailed in this dissertation. First, we developed a synthetic method that can fine tune the amount of chemically accessible organic functional groups on the pores surface of MSN by exploiting electrostatic and size matching between the cationic alkylammonium head group of the cetyltrimethylammonium bromide (CTAB) surfactant and various anionic organoalkoxysilane precursors at the micelle-water interface in a base-catalyzed condensation reaction of silicate. Aiming nature imitation, we demonstrated the catalytic abilities of the MSNs, We utilized an ethylenediamine functional group for chelating Cu{sup 2+} as a catalytic functional group anchored inside the mesopores. Thus, a polyalkynylene-based conducting polymer (molecular wire) was synthesized within the Cu-functionalized MSNs silica catalyst. For sensing applications, we have synthesized a poly(lactic acid) coated mesoporous silica nanosphere (PLA-MSN) material that serves as a fluorescence sensor system for detection of amino-containing neurotransmitters in neutral aqueous buffer. We exploited the mesoporosity of MSNs for encapsulating pharmaceutical drugs. We examined bio-friendly capping molecules such as polyamidoamine dendrimers of generations G2 to G4, to prevent the drug leaching. Next, the drug delivery system employed MSNs loaded with Doxorubicin, an anticancer drug. The results demonstrated that these nano-Trojan horses have ability to deliver Doxorubicin to cancer cells and induce their death. Finally, to demonstrate the potential of MSN as an universal cellular transmembrane nanovehicle, we anchored positively charged dendrimers on the surface of MSN and utilize them to complex cationic DNA. The p-EGFP-CI gene-coated MSN nanocomposite was able to transfect cancer cell lines, such as human HeLa and CHO cancer cell lines. The gene carrier ability of MSNs was further proved by transfecting primary cells and cotransfecting of two different genes in cancer cell lines. In sum, MSN are versatile partners in several types of applications.

  20. Reduction and aggregation of silver in aqueous gelatin and silica suspensions

    SciTech Connect (OSTI)

    Kapoor, S.; Lawless, D.; Kennepohl, P.; Meisel, D. [Argonne National Lab., IL (United States); Serpone, N. [Concordia Univ., Montreal, Quebec (Canada)

    1994-06-01T23:59:59.000Z

    The investigation of silver reduction and aggregation processes are of specific interest to the photographic industry, which relies heavily on photochemical equivalents of these reactions. Mechanistic insights into the formation of small silver clusters in aqueous solution have been obtained from both pulse and {gamma}-radiolytic studies. This paper examines the reduction of silver ions and the subsequent formation of silver clusters in aqueous gelatin solutions and on colloidal silica particles using the pulse radiolysis technique. The aggregation processes are compared with the parallel reactions in aqueous solutions.

  1. Size and spatial homogeneity of SiGe quantum dots in amorphous silica matrix

    SciTech Connect (OSTI)

    Buljan, Maja [Faculty of Mathematics and Physics, Charles University in Prague, Prague 12116 (Czech Republic); Ruder Boskovic Institute, P.O. Box 180, 10002 Zagreb (Croatia); Pinto, Sara R. C.; Rolo, Anabela G.; Levichev, Sergey; Gomes, Maria J. M. [Physics Department, University of Minho, 4710-057 Braga (Portugal); Kashtiban, Reza J.; Bangert, Ursel [Nanostructured Materials Research Group, School of Materials, University of Manchester, P.O. Box 88, Manchester, M1 7HS (United Kingdom); Chahboun, Adil [Physics Department, University of Minho, 4710-057 Braga (Portugal); Department of Physics, Dhar Mehraz Sciences Faculty, BP 1796, Fes (Morocco); Holy, Vaclav [Faculty of Mathematics and Physics, Charles University in Prague, Prague 12116 (Czech Republic)

    2009-10-15T23:59:59.000Z

    In this paper, we present a study of structural properties of SiGe quantum dots formed in amorphous silica matrix by magnetron sputtering technique. We investigate deposition conditions leading to the formation of dense and uniformly sized quantum dots, distributed homogeneously in the matrix. X-ray and Raman spectroscopy were used to estimate the Si content. A detailed analysis based on grazing incidence small angle x-ray scattering revealed the influence of the deposition conditions on quantum dot sizes, size distributions, spatial arrangement, and concentration of quantum dots in the matrix, as well as the Si:Ge content.

  2. Laser induced damage of fused silica polished optics due to a droplet forming organic contaminant

    SciTech Connect (OSTI)

    Bien-Aime, Karell; Neauport, Jerome; Tovena-Pecault, Isabelle; Fargin, Evelyne; Labrugere, Christine; Belin, Colette; Couzi, Michel

    2009-04-20T23:59:59.000Z

    We report on the effect of organic molecular contamination on single shot laser induced damage density at the wavelength of 351 nm, with a 3 ns pulse length. Specific contamination experiments were made with dioctylphthalate (DOP) in liquid or gaseous phase, on the surface of fused silica polished samples, bare or solgel coated. Systematic laser induced damage was observed only in the case of liquid phase contamination. Different chemical and morphological characterization methods were used to identify and understand the damage process. We demonstrate that the contaminant morphology, rather than its physicochemical nature, can be responsible for the decrease of laser induced damage threshold of optics.

  3. Role of suprathermal electrons during nanosecond laser energy deposit in fused silica

    SciTech Connect (OSTI)

    Grua, P.; Hébert, D.; Lamaignère, L.; Rullier, J.-L. [CEA, DAM, CESTA, F-33114 Le Barp (France)

    2014-08-25T23:59:59.000Z

    An accurate description of interaction between a nanosecond laser pulse and a wide band gap dielectric, such as fused silica, requires the understanding of energy deposit induced by temperature changes occurring in the material. In order to identify the fundamental processes involved in laser-matter interaction, we have used a 1D computational model that allows us to describe a wide set of physical mechanisms and intended for comparison with specially designed “1D experiments.” We have pointed out that suprathermal electrons are very likely implicated in heat conduction, and this assumption has allowed the model to reproduce the experiments.

  4. Transport parameter determination and modeling of sodium and strontium plumes at the Idaho National Engineering Laboratory

    E-Print Network [OSTI]

    Londergan, John Thomas

    1987-01-01T23:59:59.000Z

    TRANSPORT PARAMETER DETERMINATION AND MODELING OF SODIUM AND STRONTIUM PLUMES AT THE IDAHO NATIONAL ENGINEERING LABORATORY A Thesis by JOHN THOMAS LONDERGAN Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE May 1987 Major Subject: Geophysics TRANSPORT PARAMETER DETERMINATION AND MODELING OF SODIUM AND STRONTIUM PLUMES AT THE IDAHO NATIONAL ENGINEERING LABORATORY A Thesis by JOHN THOMAS LONDERGAN Approved...

  5. Sodium and potassium levels in the serum of acutely irradiated and non-irradiated rats

    E-Print Network [OSTI]

    Shepherd, David Preston

    1967-01-01T23:59:59.000Z

    SODIUM AND POTASSIUM LEVELS IN THE SERUM OF ACUTELY IRRADIATED AND NON-IRRADIATED RATS A Thesis By DAVID PRESTON SHEPHERD Submitted to the Graduate College of the Texas ARM University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE August 1967 Major Subject: Zoology SODIUM AND POTASSIUM LEVELS IN THE SERUM OF ACUTELY IRRADIATED AND NON-IRRADIATED RATS A Thesis By DAVID PRESTON SHEPHERD Approved as to style and content by: (Chairman of Committee) (Head...

  6. Penetration mechanism and distribution gradients of sodium tripolyphosphate in peeled and deveined shrimp

    E-Print Network [OSTI]

    Tenhet, Vickie Lynn

    1979-01-01T23:59:59.000Z

    PENETRATION MECHANISM AND DISTRIBUTION GRADIENTS OF SODIUM TRIPOLYPHOSPHATE IN PEELED AND DEVEINED SHRIMP A Thesis by VICKIE LYNN TENHET Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE December 1979 Major Subject: Food Science and Technology PENETRATION MECHANISM AND DISTRIBUTION GRADIENTS OF SODIUM TRIPOLYPHOSPHATE IN PEELED AND DEVEINED SHRIMP A Thesis by VICKIE LYNN TENHET Approved as to style...

  7. The effect of sodium chloride in the irrigation water on the growth of selected ornamental plants 

    E-Print Network [OSTI]

    Apps, Gary Edward

    1976-01-01T23:59:59.000Z

    THE EFFECT OF SODIUM CHLORIDE IN THE IRRIGATION WATER ON THE GROWTH OF SELECTED ORNAMENTAL PLANTS A Thesis by GARY EDWARD APPS Submitted to the Graduate College of Texas A6M University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE December 1976 Major Subject: Floriculture THE EFFECT OF SODIUM CHLORIDE IN THE IRRIGATION WATER ON THE GROWTH OF SELECTED ORNAMENTAL PLANTS A Thesis by GARY EDWARD APPS Approved as to style and content by: (Chairman of Committee...

  8. The tolerance of two varieties of cotton to relatively high levels of sodium and magnesium 

    E-Print Network [OSTI]

    Parekh, Manhar C

    1969-01-01T23:59:59.000Z

    THE TO'ERANCE OF TNO VARIETIES OF COTTON TO RELATIVELY HIGH LEVELS OF SODIUM AND MAGNESIUM A Tnesis by Msnhar C. Parekh Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree...) (Nember) (Nemb ) August 1969 ABSTRACT The Tolerance of Two Varieties of Cotton to Relatively High Levels of Sodium and Magnesium. (August 1969) Masher C. Parekh, B. S. , Gujarat University, Directed by: Dr. H. E. Joham An experiment was conducted...

  9. Solar-thermal Water Splitting Using the Sodium Manganese Oxide Process & Preliminary H2A Analysis

    SciTech Connect (OSTI)

    Todd M. Francis, Paul R. Lichty, Christopher Perkins, Melinda Tucker, Peter B. Kreider, Hans H. Funke, Allan Lewandowski, and Alan W. Weimer

    2012-10-24T23:59:59.000Z

    There are three primary reactions in the sodium manganese oxide high temperature water splitting cycle. In the first reaction, Mn2O3 is decomposed to MnO at 1,500°C and 50 psig. This reaction occurs in a high temperature solar reactor and has a heat of reaction of 173,212 J/mol. Hydrogen is produced in the next step of this cycle. This step occurs at 700°C and 1 atm in the presence of sodium hydroxide. Finally, water is added in the hydrolysis step, which removes NaOH and regenerates the original reactant, Mn2O3. The high temperature solar�driven step for decomposing Mn2O3 to MnO can be carried out to high conversion without major complication in an inert environment. The second step to produce H2 in the presence of sodium hydroxide is also straightforward and can be completed. The third step, the low temperature step to recover the sodium hydroxide is the most difficult. The amount of energy required to essentially distill water to recover sodium hydroxide is prohibitive and too costly. Methods must be found for lower cost recovery. This report provides information on the use of ZnO as an additive to improve the recovery of sodium hydroxide.

  10. An evaluation of neutralization for processing sodium-bearing liquid waste

    SciTech Connect (OSTI)

    Chipman, N.A.; Engelgau, G.O.; Berreth, J.R.

    1989-01-01T23:59:59.000Z

    This report addresses an alternative concept for potentially managing the sodium-bearing liquid waste generated at the Idaho Chemical Processing Plant from the current method of calcining a blend of sodium waste and high-level liquid waste. The concept is based on removing the radioactive components from sodium-bearing waste by neutralization and grouting the resulting low-level waste for on-site near-surface disposal. Solidifying the sodium waste as a remote-handled transuranic waste is not considered to be practical because of excessive costs and inability to dispose of the waste in a timely fashion. Although neutralization can remove most radioactive components to provide feed for a solidified low-level waste, and can reduce liquid inventories four to nine years more rapidly than the current practice of blending sodium-bearing liquid waste with first-cycle raffinite, the alternative will require major new facilities and will generate large volumes of low-level waste. Additional facility and operating costs are estimated to be at least $500 million above the current practice of blending and calcining. On-site, low-level waste disposal may be technically difficult and conflict which national and state policies. Therefore, it is recommended that the current practice of calcining a blend of sodium-bearing liquid waste and high-level liquid waste be continued to minimize overall cost and process complexities. 17 refs., 4 figs., 16 tabs.

  11. Optically transparent superhydrophobic silica-based films H.M. Shang*, Y. Wang, S.J. Limmer, T.P. Chou, K. Takahashi, G.Z. Cao

    E-Print Network [OSTI]

    Cao, Guozhong

    Optically transparent superhydrophobic silica-based films H.M. Shang*, Y. Wang, S.J. Limmer, T superhydrophobic silica-based films were obtained by means of sol­gel processing and self-assembly (SA). Desired and superhydrophobicity are required, in addition to low temperature processing. In addition, such films can be made

  12. Ultra-large bandwidth hollow-core guiding in all-silica Bragg fibers with nano-supports

    E-Print Network [OSTI]

    Vienne, G; Jakobsen, C; Deyerl, H J; Jensen, J B; Sorensen, T; Hansen, T P; Huang, Y; Terrel, M; Lee, R K; Mortensen, N A; Broeng, J; Simonsen, H; Bjarklev, A; Yariv, A

    2004-01-01T23:59:59.000Z

    We demonstrate a new class of hollow-core Bragg fibers that are composed of concentric cylindrical silica rings separated by nanoscale support bridges. We theoretically predict and experimentally observe hollow-core confinement over an octave frequency range. The bandwidth of bandgap guiding in this new class of Bragg fibers exceeds that of other hollow-core fibers reported in the literature. With only three rings of silica cladding layers, these Bragg fibers achieve propagation loss of the order of 1 dB/m.

  13. Formation of laser-induced periodic surface structures on fused silica upon two-color double-pulse irradiation

    SciTech Connect (OSTI)

    Höhm, S.; Herzlieb, M.; Rosenfeld, A. [Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie (MBI), Max-Born-Straße 2A, D-12489 Berlin (Germany)] [Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie (MBI), Max-Born-Straße 2A, D-12489 Berlin (Germany); Krüger, J.; Bonse, J. [BAM Bundesanstalt für Materialforschung und –prüfung, Unter den Eichen 87, D-12205 Berlin (Germany)] [BAM Bundesanstalt für Materialforschung und –prüfung, Unter den Eichen 87, D-12205 Berlin (Germany)

    2013-12-16T23:59:59.000Z

    The formation of laser-induced periodic surface structures (LIPSS) upon irradiation of fused silica with multiple irradiation sequences consisting of laser pulse pairs (50 fs single-pulse duration) of two different wavelengths (400 and 800 nm) is studied experimentally. Parallel polarized double-pulse sequences with a variable delay ?t between ?10 and +10 ps and between the individual fs-laser pulses were used to investigate the LIPSS periods versus ?t. These two-color experiments reveal the importance of the ultrafast energy deposition to the silica surface by the first laser pulse for LIPSS formation. The second laser pulse subsequently reinforces the previously seeded spatial LIPSS frequencies.

  14. SILICA GEL BEHAVIOR UNDER DIFFERENT EGS CHEMICAL AND THERMAL CONDITIONS: AN EXPERIMENTAL STUDY

    SciTech Connect (OSTI)

    Hunt, J D; Ezzedine, S M; Bourcier, W; Roberts, S

    2012-01-19T23:59:59.000Z

    Fractures and fracture networks are the principal pathways for migration of water and contaminants in groundwater systems, fluids in enhanced geothermal systems (EGS), oil and gas in petroleum reservoirs, carbon dioxide leakage from geological carbon sequestration, and radioactive and toxic industrial wastes from underground storage repositories. When dealing with EGS fracture networks, there are several major issues to consider, e.g., the minimization of hydraulic short circuits and losses of injected geothermal fluid to the surrounding formation, which in turn maximize heat extraction and economic production. Gel deployments to direct and control fluid flow have been extensively and successfully used in the oil industry for enhanced oil recovery. However, to the best of our knowledge, gels have not been applied to EGS to enhance heat extraction. In-situ gelling systems can either be organic or inorganic. Organic polymer gels are generally not thermostable to the typical temperatures of EGS systems. Inorganic gels, such as colloidal silica gels, however, may be ideal blocking agents for EGS systems if suitable gelation times can be achieved. In the current study, we explore colloidal silica gelation times and rheology as a function of SiO{sub 2} concentration, pH, salt concentration, and temperature, with preliminary results in the two-phase field above 100 C. Results at 25 C show that it may be possible to choose formulations that will gel in a reasonable and predictable amount of time at the temperatures of EGS systems.

  15. High resolution transmission electron microscopy of melamine-formaldehyde aerogels and silica aerogels

    SciTech Connect (OSTI)

    Ruben, G.C. (Dartmouth Coll., Hanover, NH (United States). Dept. of Biological Sciences)

    1991-09-01T23:59:59.000Z

    The goal of the high resolution transmission electron microscopy (HRTEM) was to image the structure of two tetramethyl orthosilicate (TMOS) and two melamine-formaldehyde (MF) aerogels at the single polymer chain level{sup 1,2}. With this level of structural resolution we hoped to interrelate each aerogel's structure with its physical properties and its method of synthesis. Conventional single-step base catalysed TMOS aerogels show strings of spheroidal particles linked together with minimal necking. The spheroidal particles range from 86--132 {Angstrom} and average 113{plus minus}10 {Angstrom} in diameter{sup 2}. In contrast the TMOS aerogels reported on here were made by a two step method. After extended silica chains are grown in solution under acidic conditions with a substoichiometric amount of water, the reaction is stopped and the methanol hydrolysed from TMOS is removed. Then base catalysis and additional water are added to cause gel formation is a nonalcoholic solvent. The MF aerogels were prepared for HRTEM by fracturing them on a stereo microscope stage with razor knife so that fractured pieces with smooth flat surfaces could be selected for platinum-carbon replication. The two silica (TMOS) aerogels were both transparent and difficult to see. These aerogels were fractured on a stereo microscope stage with tweezers. 6 refs., 4 figs.

  16. Vapor Sensing Using Conjugated Molecule-Linked Au Nanoparticles in a Silica Matrix

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

    Dirk, Shawn M.; Howell, Stephen W.; Price, B. Katherine; Fan, Hongyou; Washburn, Cody; Wheeler, David R.; Tour, James M.; Whiting, Joshua; Simonson, R. Joseph

    2009-01-01T23:59:59.000Z

    Cross-linked assemblies of nanoparticles are of great value as chemiresistor-type sensors. Herein, we report a simple method to fabricate a chemiresistor-type sensor that minimizes the swelling transduction mechanism while optimizing the change in dielectric response. Sensors prepared with this methodology showed enhanced chemoselectivity for phosphonates which are useful surrogates for chemical weapons. Chemoselective sensors were fabricated using an aqueous solution of gold nanoparticles that were then cross-linked in the presence of the silica precursor, tetraethyl orthosilicate with the?-,?-dithiolate (which is derived from the in situ deprotection of 1,4-di(Phenylethynyl-4?,4?-diacetylthio)-benzene (1) with wet triethylamine). The cross-linked nanoparticles and silica matrix were dropmore »coated onto interdigitated electrodes having 8??m spacing. Samples were exposed to a series of analytes including dimethyl methylphosphonate (DMMP), octane, and toluene. A limit of detection was obtained for each analyte. Sensors assembled in this fashion were more sensitive to dimethyl methylphosphonate than to octane by a factor of 1000.« less

  17. Power scaling analysis of fiber lasers and amplifiers based on non-silica materials

    SciTech Connect (OSTI)

    Dawson, J W; Messerly, M J; Heebner, J E; Pax, P H; Sridharan, A K; Bullington, A L; Beach, R J; Siders, C W; Barty, C P; Dubinskii, M

    2010-03-30T23:59:59.000Z

    A developed formalism for analyzing the power scaling of diffraction limited fiber lasers and amplifiers is applied to a wider range of materials. Limits considered include thermal rupture, thermal lensing, melting of the core, stimulated Raman scattering, stimulated Brillouin scattering, optical damage, bend induced limits on core diameter and limits to coupling of pump diode light into the fiber. For conventional fiber lasers based upon silica, the single aperture, diffraction limited power limit was found to be 36.6kW. This is a hard upper limit that results from an interaction of the stimulated Raman scattering with thermal lensing. This result is dependent only upon physical constants of the material and is independent of the core diameter or fiber length. Other materials will have different results both in terms of ultimate power out and which of the many limits is the determining factor in the results. Materials considered include silica doped with Tm and Er, YAG and YAG based ceramics and Yb doped phosphate glass. Pros and cons of the various materials and their current state of development will be assessed. In particular the impact of excess background loss on laser efficiency is discussed.

  18. Physisorbed films in periodic mesoporous silica studied by in situ synchrotron small-angle diffraction

    SciTech Connect (OSTI)

    Zickler, Gerald A.; Wagermaier, Wolfgang; Paris, Oskar [Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, D-14424 Potsdam (Germany); Jaehnert, Susanne; Findenegg, Gerhard H. [Stranski Laboratory of Physical and Theoretical Chemistry, Technical University Berlin, Strasse des 17. Juni 135, D-10623 Berlin (Germany); Funari, Sergio S. [Hamburger Synchrotronstrahlungslabor (HASYLAB), Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, D-22603 Hamburg (Germany)

    2006-05-01T23:59:59.000Z

    Adsorption and capillary condensation of an organic fluid in a periodic mesoporous silica (SBA-15) are studied by in situ synchrotron diffraction. Powder diffraction patterns resulting from the two-dimensional hexagonal packing of the cylindrical pores of SBA-15 are collected as a function of vapor pressure during continuous adsorption and desorption of the fluid (perfluoropentane C{sub 5}F{sub 12}), using a specially designed sorption cell. Seven diffraction peaks with systematic changes of the intensity are resolved as the adsorbed film thickness increases along the adsorption isotherm. The integrated intensities of the diffraction peaks are analyzed with a structural model involving four levels of electron density (dense silica matrix, microporous corona around the pores, adsorbed film, and core space of the pores). The model provides quantitative information about the structure of the evacuated specimen, the filling of the corona, and the growing thickness of the liquid film with increasing pressure. A very good fit of the data by this model is found for relative pressures up to p/p{sub 0}{approx_equal}0.5, but the fit of the high-indexed diffraction peaks becomes poor close to the capillary condensation pressure (p/p{sub 0}{approx_equal}0.68). Tentatively, this fact may be attributed to a deviation of the liquid film structure from the simple flat geometry close to the phase transformation, presumably caused by density fluctuations.

  19. Critical behavior of the liquid gas transition of 4 He confined in a silica aerogel

    E-Print Network [OSTI]

    Geoffroy Aubry; Fabien Bonnet; Mathieu Melich; Laurent Guyon; Florence Despetis; Pierre-Etienne Wolf

    2015-06-25T23:59:59.000Z

    We have studied 4 He confined in a 95% porosity silica aerogel in the vicinity of the bulk liquid gas critical point. Both thermodynamic measurements and light scattering experiments were performed to probe the effect of a quenched disorder on the liquid gas transition, in relation with the Random Field Ising Model (RFIM). We find that the hysteresis between condensation and evaporation present at lower temperatures disappears at a temperature T ch between 25 and 30 mK below the critical point. Slow relaxations are observed for temperatures slightly below T ch , indicating that some energy barriers, but not all, can be overcome. Above T ch , no density step is observed along the (reversible) isotherms, showing that the critical behavior of the equilibrium phase transition in presence of disorder, if it exists, is shifted to smaller temperatures, where it cannot be observed due to the impossibility to reach equilibrium. Above T ch , light scattering exhibits a weak maximum close to the pressure where the isotherm slope is maximal. This behavior can be accounted for by a simple model incorporating the compression of 4 He close to the silica strands.

  20. Dynamics of tungsten hexacarbonyl, dicobalt octacarbonyl, and their fragments adsorbed on silica surfaces

    SciTech Connect (OSTI)

    Muthukumar, Kaliappan; Valentí, Roser; Jeschke, Harald O. [Institut für Theoretische Physik, Goethe-Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt am Main (Germany)] [Institut für Theoretische Physik, Goethe-Universität Frankfurt, Max-von-Laue-Straße 1, 60438 Frankfurt am Main (Germany)

    2014-05-14T23:59:59.000Z

    Tungsten and cobalt carbonyls adsorbed on a substrate are typical starting points for the electron beam induced deposition of tungsten or cobalt based metallic nanostructures. We employ first principles molecular dynamics simulations to investigate the dynamics and vibrational spectra of W(CO){sub 6} and W(CO){sub 5} as well as Co{sub 2}(CO){sub 8} and Co(CO){sub 4} precursor molecules on fully and partially hydroxylated silica surfaces. Such surfaces resemble the initial conditions of electron beam induced growth processes. We find that both W(CO){sub 6} and Co{sub 2}(CO){sub 8} are stable at room temperature and mobile on a silica surface saturated with hydroxyl groups (OH), moving up to half an Angström per picosecond. In contrast, chemisorbed W(CO){sub 5} or Co(CO){sub 4} ions at room temperature do not change their binding site. These results contribute to gaining fundamental insight into how the molecules behave in the simulated time window of 20 ps and our determined vibrational spectra of all species provide signatures for experimentally distinguishing the form in which precursors cover a substrate.

  1. Hyperpolarized Xe-129 NMR Investigation of Ammonia Borane in Mesoporous Silica

    SciTech Connect (OSTI)

    Wang, Li Q.; Karkamkar, Abhijeet J.; Autrey, Thomas; Exarhos, Gregory J.

    2009-04-23T23:59:59.000Z

    Hyperpolarized (HP) 129Xe NMR was used for the first time to probe the porosity for nanophase ammonium borane (AB) infused in mesoporous silica (MCM). Variable temperature HP 129Xe NMR measurements have been systematically carried out on a series of AB:MCM materials with different AB loading. Three distinct types of pore environments are clearly evident: pristine mesopores; pores coated with AB inside the meso-channels, and inter-particle spacing formed from AB aggregates outside the meso-channels. We found similarly uniform coating of AB on mesoporous silica channels with 1:2 and 1:1 AB:MCM loading (ratio of weight percent). When the loading of AB to MCM is larger than 1:1, AB starts to aggregate outside the meso-channels. Further increases in loading (? 3:1) result in the formation of partially blocked meso-channels as a result of excessive AB loading. The detailed information obtained from this study on how supported AB resides in nanoporous channels and how it evolves with the increase of AB loading is helpful for rational design of novel materials with optimal hydrogen storage and release properties.

  2. Study on the thermal resistance in secondary particles chain of silica aerogel by molecular dynamics simulation

    SciTech Connect (OSTI)

    Liu, M. [Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing100190 (China); Department of Physics, University of Chinese Academy of Sciences, Beijing 100049 (China); Qiu, L., E-mail: qiulin111@sina.com, E-mail: jzzhengxinghua@163.com; Zheng, X. H., E-mail: qiulin111@sina.com, E-mail: jzzhengxinghua@163.com; Zhu, J.; Tang, D. W. [Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing100190 (China)

    2014-09-07T23:59:59.000Z

    In this article, molecular dynamics simulation was performed to study the heat transport in secondary particles chain of silica aerogel. The two adjacent particles as the basic heat transport unit were modelled to characterize the heat transfer through the calculation of thermal resistance and vibrational density of states (VDOS). The total thermal resistance of two contact particles was predicted by non-equilibrium molecular dynamics simulations (NEMD). The defects were formed by deleting atoms in the system randomly first and performing heating and quenching process afterwards to achieve the DLCA (diffusive limited cluster-cluster aggregation) process. This kind of treatment showed a very reasonable prediction of thermal conductivity for the silica aerogels compared with the experimental values. The heat transport was great suppressed as the contact length increased or defect concentration increased. The constrain effect of heat transport was much significant when contact length fraction was in the small range (<0.5) or the defect concentration is in the high range (>0.5). Also, as the contact length increased, the role of joint thermal resistance played in the constraint of heat transport was increasing. However, the defect concentration did not affect the share of joint thermal resistance as the contact length did. VDOS of the system was calculated by numerical method to characterize the heat transport from atomic vibration view. The smaller contact length and greater defect concentration primarily affected the longitudinal acoustic modes, which ultimately influenced the heat transport between the adjacent particles.

  3. Study of a Threshold Cherenkov Counter Based on Silica Aerogels with Low Refractive Indices

    E-Print Network [OSTI]

    I. Adachi et al

    1994-12-13T23:59:59.000Z

    To identify $\\pi^{\\pm}$ and $K^{\\pm}$ in the region of $1.0\\sim 2.5$ GeV/c, a threshold Cherenkov counter equipped with silica aerogels has been investigated. Silica aerogels with a low refractive index of 1.013 have been successfully produced using a new technique. By making use of these aerogels as radiators, we have constructed a Cherenkov counter and have checked its properties in a test beam. The obtained results have demonstrated that our aerogel was transparent enough to make up for loss of the Cherenkov photon yield due to a low refractive index. Various configurations for the photon collection system and some types of photomultipliers, such as the fine-mesh type, for a read out were also tested. From these studies, our design of a Cherenkov counter dedicated to $\\pi / K$ separation up to a few GeV/c %in the momentum range of $1.0 \\sim 2.5$ GeV/c with an efficiency greater than $90$ \\% was considered.

  4. Pore-structure determinations of silica aerogels by {sup 129}Xe NMR spectroscopy and imaging.

    SciTech Connect (OSTI)

    Gregory, D. M.; Gerald, R. E., II; Botto, R. E.; Chemistry

    1998-04-01T23:59:59.000Z

    Silica aerogels represent a new class of open-pore materials with pore dimensions on a scale of tens of nanometers, and are thus classified as mesoporous materials. In this work, we show that the combination of NMR spectroscopy and chemical-shift selective magnetic resonance imaging (MRI) can resolve some of the important aspects of the structure of silica aerogels. The use of xenon as a gaseous probe in combination with spatially resolved NMR techniques is demonstrated to be a powerful, new approach for characterizing the average pore structure and steady-state spatial distributions of xenon atoms in different physicochemical environments. Furthermore, dynamic NMR magnetization transfer experiments and pulsed-field gradient (PFG) measurements have been used to characterize exchange processes and diffusive motion of xenon in samples at equilibrium. In particular, this new NMR approach offers unique information and insights into the nanoscopic pore structure and microscopic morphology of aerogels and the dynamical behavior of occluded adsorbates. MRI provides spatially resolved information on the nature of the flaw regions found in these materials. Pseudo-first-order rate constants for magnetization transfer among the bulk and occluded xenon phases indicate xenon-exchange rate constants on the order of 1 s-1 for specimens having volumes of 0.03 cm3. PFG diffusion measurements show evidence of anisotropic diffusion for xenon occluded within aerogels, with nominal self-diffusivity coefficients on the order of D= 10-3cm2/s.

  5. Synthesis and characterization of nanoparticulate MnS within the pores of mesoporous silica

    SciTech Connect (OSTI)

    Barry, Louse; Copley, Mark [Department of Chemistry, University College Cork, Cork (Ireland); Holmes, Justin D. [Department of Chemistry, University College Cork, Cork (Ireland); Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2 (Ireland); Otway, David J. [Department of Chemistry, University College Cork, Cork (Ireland); Kazakova, Olga [National Physical Laboratory, Teddington (United Kingdom); Morris, Michael A. [Department of Chemistry, University College Cork, Cork (Ireland); Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2 (Ireland)], E-mail: m.morris@ucc.ie

    2007-12-15T23:59:59.000Z

    Mesoporous silica was loaded with nanoparticulate MnS via a simple post-synthesis treatment. The mesoporous material that still contained surfactant was passivated to prevent MnS formation at the surface. The surfactant was extracted and a novel manganese ethylxanthate was used to impregnate the pore network. This precursor thermally decomposes to yield MnS particles that are smaller or equal to the pore size. The particles exhibit all three common polymorphs. The passivation treatment is most effective at lower loadings because at the highest loadings (SiO{sub 2}:MnS molar ratio of 6:1) large particles (>50 nm) form at the exterior of the mesoporous particles. The integrity of the mesoporous network is maintained through the preparation and high order is maintained. The MnS particles exhibit unexpected ferromagnetism at low temperatures. Strong luminescence of these samples is observed and this suggests that they may have a range of important application areas. - Graphical abstract: A novel manganese ethylxanthate precursor was used to impregnate the pore network of mesoporous silica and was decomposed to yield MnS particles smaller or equal to the pore size. The particles exhibit all three common polymorphs, demonstrate unexpected ferromagnetism at low temperatures and display a strong luminescence.

  6. Synthesis and single crystal structure refinement of the one-layer hydrate of sodium brittle mica

    SciTech Connect (OSTI)

    Kalo, Hussein; Milius, Wolfgang [Lehrstuhl fuer Anorganische Chemie I, University of Bayreuth, D-95440 Bayreuth (Germany)] [Lehrstuhl fuer Anorganische Chemie I, University of Bayreuth, D-95440 Bayreuth (Germany); Braeu, Michael [BASF Construction Chemicals GmbH, 83308 Trostberg (Germany)] [BASF Construction Chemicals GmbH, 83308 Trostberg (Germany); Breu, Josef, E-mail: Josef.Breu@uni-bayreuth.de [Lehrstuhl fuer Anorganische Chemie I, University of Bayreuth, D-95440 Bayreuth (Germany)] [Lehrstuhl fuer Anorganische Chemie I, University of Bayreuth, D-95440 Bayreuth (Germany)

    2013-02-15T23:59:59.000Z

    A sodium brittle mica with the ideal composition [Na{sub 4}]{sup inter}[Mg{sub 6}]{sup oct}[Si{sub 4}Al{sub 4}]{sup tet}O{sub 20}F{sub 4} was synthesized via melt synthesis in a gas tight crucible. This mica is unusual inasmuch as the known mica structure holds only room for two interlayer cations per unit cell and inasmuch as it readily hydrates despite the high layer charge while ordinary micas and brittle micas are non-swelling. The crystal structure of one-layer hydrate sodium brittle mica was determined and refined from single crystal X-ray data. Interlayer cations reside at the center of the distorted hexagonal cavities and are coordinated by the three inner basal oxygen atoms. The coordination of the interlayer cation is completed by three interlayer water molecules residing at the center of the interlayer region. The relative position of adjacent 2:1-layers thus is fixed by these octahedrally coordinated interlayer cations. Pseudo-symmetry leads to extensive twinning. In total five twin operations generate the same environment for the interlayer species and are energetically degenerate. - Graphical abstract: The sodium brittle mica has been successfully synthesized by melt synthesis and the crystal structure of the one-layer hydrate of sodium brittle mica was determined from single crystal X-ray diffraction data. Highlights: Black-Right-Pointing-Pointer Melt synthesis yielded coarse grained sodium brittle mica which showed little disorder. Black-Right-Pointing-Pointer Sodium brittle mica hydrated completely to the state of one-layer hydrate. Black-Right-Pointing-Pointer Structure of one-layer hydrate of sodium brittle mica could therefore be determined and refined. Black-Right-Pointing-Pointer Arrangement of upper and lower tetrahedral sheet encompassing interlayer cation were clarified.

  7. Sustained Recycle in Light Water and Sodium-Cooled Reactors

    SciTech Connect (OSTI)

    Steven J. Piet; Samuel E. Bays; Michael A. Pope; Gilles J. Youinou

    2010-11-01T23:59:59.000Z

    From a physics standpoint, it is feasible to sustain recycle of used fuel in either thermal or fast reactors. This paper examines multi-recycle potential performance by considering three recycling approaches and calculating several fuel cycle parameters, including heat, gamma, and neutron emission of fresh fuel; radiotoxicity of waste; and uranium utilization. The first recycle approach is homogeneous mixed oxide (MOX) fuel assemblies in a light water reactor (LWR). The transuranic portion of the MOX was varied among Pu, NpPu, NpPuAm, or all-TRU. (All-TRU means all isotopes through Cf-252.) The Pu case was allowed to go to 10% Pu in fresh fuel, but when the minor actinides were included, the transuranic enrichment was kept below 8% to satisfy the expected void reactivity constraint. The uranium portion of the MOX was enriched uranium. That enrichment was increased (to as much as 6.5%) to keep the fuel critical for a typical LWR irradiation. The second approach uses heterogeneous inert matrix fuel (IMF) assemblies in an LWR - a mix of IMF and traditional UOX pins. The uranium-free IMF fuel pins were Pu, NpPu, NpPuAm, or all-TRU. The UOX pins were limited to 4.95% U-235 enrichment. The number of IMF pins was set so that the amount of TRU in discharged fuel from recycle N (from both IMF and UOX pins) was made into the new IMF pins for recycle N+1. Up to 60 of the 264 pins in a fuel assembly were IMF. The assembly-average TRU content was 1-6%. The third approach uses fast reactor oxide fuel in a sodium-cooled fast reactor with transuranic conversion ratio of 0.50 and 1.00. The transuranic conversion ratio is the production of transuranics divided by destruction of transuranics. The FR at CR=0.50 is similar to the CR for the MOX case. The fast reactor cases had a transuranic content of 33-38%, higher than IMF or MOX.

  8. Fractal Analysis of Flame-Synthesized Nanostructured Silica and Titania Powders Using Small-Angle X-ray

    E-Print Network [OSTI]

    Beaucage, Gregory

    Fractal Analysis of Flame-Synthesized Nanostructured Silica and Titania Powders Using Small-Angle X these powders display mass-fractal morphologies, which are composed of ramified aggregates of nanoscale primary particles. Primary particle size, aggregate size, fractal dimension, and specific surface area are obtained

  9. Preparation of Catalytic Nanoparticles in Mesoporous Silica Film for Oriented Growth of Single-Walled Carbon Nanotubes

    E-Print Network [OSTI]

    Maruyama, Shigeo

    method at the dipping rate of 2 cm/min. After the coating, the piece was dried in air at 80 o C overnight is coated on the cobalt thin film deposited by sputtering. From these investigations, it is concluded silica film should have mesopores which run through the film from the substrate to the surface. Even

  10. Benign, 3D encapsulation of sensitive mammalian cells in porous silica gels formed by LysSil nanoparticle assembly

    E-Print Network [OSTI]

    Kokkoli, Efie

    are employed for complementary assessment of cell viability. Results suggest that the physiologically relevant instability and the lack of fine control over pore size [9,10,18,19], critical for immune protection [6,19,20]. Silica matrices (i.e., gels) serve as structurally robust alterna- tives to biopolymers

  11. Spatially Heterogeneous Dynamics and Dynamic Facilitation in a Model of Viscous Silica Michael Vogel* and Sharon C. Glotzer

    E-Print Network [OSTI]

    Weeks, Eric R.

    this behavior. The mode coupling theory [1] describes many aspects of dynamical behavior at high T- stood as a simple activated bondbreaking process. Here, we perform molecular dynamics (MD) simula- tionsSpatially Heterogeneous Dynamics and Dynamic Facilitation in a Model of Viscous Silica Michael

  12. Bench Scale Application of the Hybridized Zero Valent Iron Process for the Removal of Dissolved Silica From Water

    E-Print Network [OSTI]

    Morar, Nilesh Mohan

    2014-11-12T23:59:59.000Z

    is effective. A more robust and cost-effective dissolved silica removal technique is desirable. The hybridized zero-valent iron (hZVI) process, now commercially available as Pironox™, uses zero-valent iron (Fe^0 ) as its main reactive media developed to remove...

  13. Reducing Logistics Footprints and Replenishment Demands: Nano-engineered Silica Aerogels a Proven Method for Water Treatment

    SciTech Connect (OSTI)

    Daily, W; Coleman, S; Love, A; Reynolds, J; O'Brien, K; Gammon, S

    2004-09-22T23:59:59.000Z

    Rapid deployment and the use of objective force aggressively reduce logistic footprints and replenishment demands. Maneuver Sustainment requires that Future Combat Systems be equipped with water systems that are lightweight, have small footprints, and are highly adaptable to a variety of environments. Technologies employed in these settings must be able to meet these demands. Lawrence Livermore National Laboratory has designed and previously field tested nano-engineered materials for the treatment of water. These materials have been either based on silica aerogel materials or consist of composites of these aerogels with granular activated carbon (GAC). Recent tests have proven successful for the removal of contaminants including uranium, hexavalent chromium, and arsenic. Silica aerogels were evaluated for their ability to purify water that had been spiked with the nerve agent VX (O-ethyl S-(2-diisopropylaminoethyl) methylphosphonothiolate). These results demonstrated that silica aerogels were able to remove the VX from the supply water and were nearly 30 times more adsorbent than GAC. This performance could result in REDUCING CHANGEOUT FREQUENCY BY A FACTOR OF 30 or DECREASING the VOLUME of adsorbent BY A FACTOR OF 30; thereby significantly reducing logistic footprints and replenishment demands. The use of the nano-engineered Silica Aerogel/GAC composites would provide a water purification technology that meets the needs of Future Combat Systems.

  14. Caustic Recycling Pilot Unit to Separate Sodium from LLW at Hanford Site - 12279

    SciTech Connect (OSTI)

    Pendleton, Justin; Bhavaraju, Sai; Priday, George; Desai, Aditya; Duffey, Kean; Balagopal, Shekar [Ceramatec Inc., Salt Lake City, UT 84119 (United States)

    2012-07-01T23:59:59.000Z

    As part of the Department of Energy (DOE) sponsored Advanced Remediation Technologies initiative, a scheme was developed to combine Continuous Sludge Leaching (CSL), Near-Tank Cesium Removal (NTCR), and Caustic Recycling Unit (CRU) using Ceramatec technology, into a single system known as the Pilot Near-Tank Treatment System (PNTTS). The Cesium (Cs) decontaminated effluent from the NTCR process will be sent to the caustic recycle process for recovery of the caustic which will be reused in another cycle of caustic leaching in the CSL process. Such an integrated mobile technology demonstration will give DOE the option to insert this process for sodium management at various sites in Hanford, and will minimize the addition of further sodium into the waste tanks. This allows for recycling of the caustic used to remove aluminum during sludge washing as a pretreatment step in the vitrification of radioactive waste which will decrease the Low Level Waste (LLW) volume by as much as 39%. The CRU pilot process was designed to recycle sodium in the form of pure sodium hydroxide. The basis for the design of the 1/4 scale pilot caustic recycling unit was to demonstrate the efficient operation of a larger scale system to recycle caustic from the NTCR effluent stream from the Parsons process. The CRU was designed to process 0.28 liter/minute of NTCR effluent, and generate 10 M concentration of 'usable' sodium hydroxide. The proposed process operates at 40 deg. C to provide additional aluminum solubility and then recover the sodium hydroxide to the point where the aluminum is saturated at 40 deg. C. A system was developed to safely separate and vent the gases generated during operation of the CRU with the production of 10 M sodium hydroxide. Caustic was produced at a rate between 1.9 to 9.3 kg/hr. The CRU was located inside an ISO container to allow for moving of the unit close to tank locations to process the LLW stream. Actual tests were conducted with the NTCR effluent simulant from the Parsons process in the CRU. The modular CRU is easily scalable as a standalone system for caustic recycling, or for NTTS integration or for use as an In-Tank Treatment System to process sodium bearing waste to meet LLW processing needs at the Hanford site. The standalone pilot operation of the CRU to recycle sodium from NTCR effluent places the technology demonstration at TRL level 6. Multiple operations were performed with the CRU to process up to 500 gallons of the NTCR effluent and demonstrate an efficient separation of up to 70 % of the sodium without solids precipitation while producing 10 M caustic. Batch mode operation was conducted to study the effects of chemistry variation, establish the processing rate, and optimize the process operating conditions to recycle caustic from the NTCR effluent. The performance of the CRU was monitored by tracking the density parameter to control the concentration of caustic produced. Different levels of sodium were separated in tests from the effluent at a fixed operating current density and temperature. The voltage of the modules remained stable during the unit operation which demonstrated steady operation to separate sodium from the NTCR effluent. The sodium transfer current efficiency was measured in testing based on the concentration of caustic produced. Measurements showed a current efficiency of 99.8% for sodium transfer from the NTCR effluent to make sodium hydroxide. The sodium and hydroxide contents of the anolyte (NTCR feed) and catholyte (caustic product) were measured before and after each batch test. In two separate batch tests, samples were taken at different levels of sodium separation and analyzed to determine the stability of the NTCR effluent after sodium separation. The stability characteristics and changes in physical and chemical properties of the NTCR effluent chemistry after separation of sodium hydroxide as a function of storage time were evaluated. Parameters such as level of precipitated alumina, total alkalinity, analysis of Al, Na, K, Cs, Fe, OH, nitrate, nitrite, total dissolved and

  15. Transparent ultralow-density silica aerogels prepared by a two-step sol-gel process

    SciTech Connect (OSTI)

    Tillotson, T.M.; Hrubesh, L.W.

    1991-09-01T23:59:59.000Z

    Conventional silica sol-gel chemistry is limited for the production of transparent ultralow-density aerogels because (1) gelation is either slow or unachievable, and (2) even when gelation is achieved, the large pore sizes result in loss of transparency for aerogels <.020 g/cc. We have developed a two-step sol-gel process that circumvents the limitations of the conventional process and allows the formation of ultralow-density gels in a matter of hours. we have found that the gel time is dependent on the catalyst concentration. After supercritical extraction, the aerogels are transparent, uncracked tiles with densities as low as .003 g/cc. 6 figs., 11 refs.

  16. Reduction of damage initiation density in fused silica optics via UV laser conditioning

    DOE Patents [OSTI]

    Peterson, John E.; Maricle, Stephen M.; Brusasco, Raymond M.; Penetrante, Bernardino M.

    2004-03-16T23:59:59.000Z

    The present invention provides a method for reducing the density of sites on the surface of fused silica optics that are prone to the initiation of laser-induced damage, resulting in optics which have far fewer catastrophic defects and are better capable of resisting optical deterioration upon exposure for a long period of time to a high-power laser beam having a wavelength of about 360 nm or less. The initiation of laser-induced damage is reduced by conditioning the optic at low fluences below levels that normally lead to catastrophic growth of damage. When the optic is then irradiated at its high fluence design limit, the concentration of catastrophic damage sites that form on the surface of the optic is greatly reduced.

  17. A molecular dynamics investigation of the unusual concentration dependencies of Fick diffusivities in silica mesopores

    SciTech Connect (OSTI)

    Krishna, Rajamani; van Baten, Jasper M

    2011-01-01T23:59:59.000Z

    Molecular Dynamics (MD) simulations were carried out to determine the self-diffusivitiy, D{sub i,self}, the Maxwell–Stefan diffusivity, Ð{sub i}, and the Fick diffusivity, D{sub i}, for methane (C1), ethane (C2), propane (C3), n-butane (nC4), n-pentane (nC5), n-hexane (nC6), n-heptane (nC7), and cyclohexane (cC6) in cylindrical silica mesopores for a range of pore concentrations. The MD simulations show that zero-loading diffusivity Ð{sub i}(0) is consistently lower, by up to a factor of 20, than the values anticipated by the classical Knudsen formula. The concentration dependence of the Fick diffusivity, D{sub i} is found to be unusually complex, and displays a strong minimum in some cases; this characteristic can be traced to molecular clustering.

  18. Liquid–solid phase transition of hydrogen and deuterium in silica aerogel

    SciTech Connect (OSTI)

    Van Cleve, E.; Worsley, M. A.; Kucheyev, S. O., E-mail: kucheyev@llnl.gov [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2014-10-28T23:59:59.000Z

    Behavior of hydrogen isotopes confined in disordered low-density nanoporous solids remains essentially unknown. Here, we use relaxation calorimetry to study freezing and melting of H{sub 2} and D{sub 2} in an ?85%-porous base-catalyzed silica aerogel. We find that liquid–solid transition temperatures of both isotopes inside the aerogel are depressed. The phase transition takes place over a wide temperature range of ?4?K and non-trivially depends on the liquid filling fraction, reflecting the broad pore size distribution in the aerogel. Undercooling is observed for both H{sub 2} and D{sub 2} confined inside the aerogel monolith. Results for H{sub 2} and D{sub 2} are extrapolated to tritium-containing hydrogens with the quantum law of corresponding states.

  19. X-ray radiographic technique for measuring density uniformity of silica aerogel

    E-Print Network [OSTI]

    Makoto Tabata; Yoshikiyo Hatakeyama; Ichiro Adachi; Takeshi Morita; Keiko Nishikawa

    2012-12-14T23:59:59.000Z

    This paper proposes a new X-ray radiographic technique for measuring density uniformity of silica aerogels used as radiator in proximity-focusing ring-imaging Cherenkov detectors. To obtain high performance in a large-area detector, a key characteristic of radiator is the density (i.e. refractive index) uniformity of an individual aerogel monolith. At a refractive index of n = 1.05, our requirement for the refractive index uniformity in the transverse plane direction of an aerogel tile is |\\delta (n - 1)/(n - 1)| aerogels from a trial production and that of Panasonic products (SP-50) as a reference, and to confirm they have sufficient density uniformity within \\pm 1% along the transverse plane direction. The measurement results show that the proposed technique can quantitatively estimate the density uniformity of aerogels.

  20. Development of transparent silica aerogel over a wide range of densities

    E-Print Network [OSTI]

    Makoto Tabata; Ichiro Adachi; Yoshikazu Ishii; Hideyuki Kawai; Takayuki Sumiyoshi; Hiroshi Yokogawa

    2011-12-21T23:59:59.000Z

    We have succeeded in developing hydrophobic silica aerogels over a wide range of densities (i.e. refractive indices). A pinhole drying method was invented to make possible producing highly transparent aerogels with entirely new region of refractive indices of 1.06-1.26. Obtained aerogels are more transparent than conventional ones, and the refractive index is well controlled in the pinhole drying process. A test beam experiment was carried out in order to evaluate the performance of the pinhole-dried aerogels as a Cherenkov radiator. A clear Cherenkov ring was successfully observed by a ring imaging Cherenkov counter. We also developed monolithic and hydrophobic aerogels with a density of 0.01 g/cm^3 (a low refractive index of 1.0026) as a cosmic dust capturer for the first time. Consequently, aerogels with any refractive indices between 1.0026 and 1.26 can be produced freely.

  1. Tanpopo cosmic dust collector: Silica aerogel production and bacterial DNA contamination analysis

    E-Print Network [OSTI]

    Tabata, Makoto; Yokobori, Shin-ichi; Kawai, Hideyuki; Takahashi, Jun-ichi; Yano, Hajime; Yamagishi, Akihiko

    2011-01-01T23:59:59.000Z

    Hydrophobic silica aerogels with ultra-low densities have been designed and developed as cosmic dust capture media for the Tanpopo mission which is proposed to be carried out on the International Space Station. Glass particles as a simulated cosmic dust with 30 \\mu m in diameter and 2.4 g/cm^3 in density were successfully captured by the novel aerogel at a velocity of 6 km/s. Background levels of contaminated DNA in the ultra-low density aerogel were lower than the detection limit of a polymerase chain reaction assay. These results show that the manufactured aerogel has good performance as a cosmic dust collector and sufficient quality in respect of DNA contamination. The aerogel is feasible for the biological analyses of captured cosmic dust particles in the astrobiological studies.

  2. X-ray radiographic technique for measuring density uniformity of silica aerogel

    E-Print Network [OSTI]

    Tabata, Makoto; Adachi, Ichiro; Morita, Takeshi; Nishikawa, Keiko; 10.1016/j.nima.2012.09.001

    2012-01-01T23:59:59.000Z

    This paper proposes a new X-ray radiographic technique for measuring density uniformity of silica aerogels used as radiator in proximity-focusing ring-imaging Cherenkov detectors. To obtain high performance in a large-area detector, a key characteristic of radiator is the density (i.e. refractive index) uniformity of an individual aerogel monolith. At a refractive index of n = 1.05, our requirement for the refractive index uniformity in the transverse plane direction of an aerogel tile is |\\delta (n - 1)/(n - 1)| aerogels from a trial production and that of Panasonic products (SP-50) as a reference, and to confirm they have sufficient density uniformity within \\pm 1% along the transverse plane direction. The measurement results show that the proposed technique can quantitatively estimate the density uniformity of aerogels.

  3. Development of transparent silica aerogel over a wide range of densities

    E-Print Network [OSTI]

    Tabata, Makoto; Ishii, Yoshikazu; Kawai, Hideyuki; Sumiyoshi, Takayuki; Yokogawa, Hiroshi; 10.1016/j.nima.2010.02.241

    2011-01-01T23:59:59.000Z

    We have succeeded in developing hydrophobic silica aerogels over a wide range of densities (i.e. refractive indices). A pinhole drying method was invented to make possible producing highly transparent aerogels with entirely new region of refractive indices of 1.06-1.26. Obtained aerogels are more transparent than conventional ones, and the refractive index is well controlled in the pinhole drying process. A test beam experiment was carried out in order to evaluate the performance of the pinhole-dried aerogels as a Cherenkov radiator. A clear Cherenkov ring was successfully observed by a ring imaging Cherenkov counter. We also developed monolithic and hydrophobic aerogels with a density of 0.01 g/cm^3 (a low refractive index of 1.0026) as a cosmic dust capturer for the first time. Consequently, aerogels with any refractive indices between 1.0026 and 1.26 can be produced freely.

  4. Hemodynamic characterization of chronic bile duct-ligated rats: effect of pentobarbital sodium

    SciTech Connect (OSTI)

    Lee, S.S.; Girod, C.; Braillon, A.; Hadengue, A.; Lebrec, D.

    1986-08-01T23:59:59.000Z

    Systemic and splanchnic hemodynamics of the chronic bile duct-ligated rat were characterized by radioactive microspheres. Conscious and pentobarbital sodium-anesthetized, bile duct-ligated and sham-operated rats had cardiac output and regional organ blood flows determined. The conscious bile duct-ligated rat compared with the sham-operated showed a hyperdynamic circulation with an increased cardiac output and portal tributary blood flow. Pentobarbital sodium anesthesia induced marked hemodynamic changes in both sham-operated and bile duct-ligated rats. The latter group was especially sensitive to its effects; thus, comparison of cardiac output and portal tributary blood flow between anesthetized bile duct-ligated and sham-operated rats showed no significant differences. The authors conclude that the rat with cirrhosis due to chronic bile duct ligation is an excellent model for hemodynamic investigations but should be studied in the conscious state, since pentobarbital sodium anesthesia eliminated the hyperdynamic circulation.

  5. Development and application of modeling tools for sodium fast reactor inspection

    SciTech Connect (OSTI)

    Le Bourdais, Florian; Marchand, Benoît; Baronian, Vahan [CEA LIST, Centre de Saclay F-91191 Gif-sur-Yvette (France)

    2014-02-18T23:59:59.000Z

    To support the development of in-service inspection methods for the Advanced Sodium Test Reactor for Industrial Demonstration (ASTRID) project led by the French Atomic Energy Commission (CEA), several tools that allow situations specific to Sodium cooled Fast Reactors (SFR) to be modeled have been implemented in the CIVA software and exploited. This paper details specific applications and results obtained. For instance, a new specular reflection model allows the calculation of complex echoes from scattering structures inside the reactor vessel. EMAT transducer simulation models have been implemented to develop new transducers for sodium visualization and imaging. Guided wave analysis tools have been developed to permit defect detection in the vessel shell. Application examples and comparisons with experimental data are presented.

  6. GIF sodium fast reactor project R and D on safety and operation

    SciTech Connect (OSTI)

    Vasile, A.; Sofu, T.; Jeong, H. Y.; Sakai, T. [CEA DEN Cadarache, DER, 13108 Saint-Paul-Lez-Durance (France)

    2012-07-01T23:59:59.000Z

    The 'Safety and Operation' project is started in 2009 within the framework of Generation-IV International Forum (GIF) Sodium Fast Reactor (SFR) research and development program. In the safety area, the project involves R and D activities on phenomenological model development and experimental programs, conceptual studies in support of the design of safety provisions, preliminary assessment of safety systems, framework and methods for analysis of safety architecture. In the operation area, the project involves R and D activities on fast reactors safety tests and analysis of reactor operations, feedback from decommissioning, in-service inspection technique development, under-sodium viewing and sodium chemistry. This paper presents a summary of such activities and the main achievements. (authors)

  7. Design and development of a high-temperature sodium compatibility testing facility

    SciTech Connect (OSTI)

    Hvasta, M. G.; Nolet, B. K.; Anderson, M. H. [Univ. of Wisconsin-Madison, 1500 Engineering Dr., Madison - ERB 841, WI 53705 (United States)

    2012-07-01T23:59:59.000Z

    The use of advanced alloys within sodium-cooled fast reactors (SFRs) has been identified as a means of increasing plant efficiency and reducing construction costs. In particular, alloys such as NF-616, NF-709 and HT-UPS are promising because they exhibit greater strength than traditional structural materials such as 316-SS. However, almost nothing is known about the sodium compatibility of these new alloys. Therefore, research taking place at the Univ. of Wisconsin-Madison is focused on studying the effects of sodium corrosion on these materials under prototypic SFR operating conditions (600 [ deg. C], V Na=10 [m/s], C 0{approx} 1 [wppm]). This paper focuses on the design and construction of the testing facility with an emphasis on moving magnet pumps (MMPs). Corrosion data from a preliminary 500 [hr] natural convection test will also be presented. (authors)

  8. Phototransformation of Polycyclic Aromatic Hydrocarbons (PAHs) on a Non-Semi Conductive Surface Such as Silica

    SciTech Connect (OSTI)

    Dabestani, R., Sigman, M.E.

    1997-09-16T23:59:59.000Z

    Polycyclic aromatic hydrocarbons (PAH), by products of fossil fuel production and consumption, constitute a large class of environmental pollutants. These toxic and sometimes carcinogenic compounds are also found in coal tar and fly ash. When released into the air, they can be sorbed onto particulates present in the atmosphere where they find their way into soil and ground water upon being washed by rain. During their residence time in the environment, PAHs will be exposed to solar radiation and may undergo phototransformation to other products. Thus, light induced photodegradation of PM`s at the solid/air interfaces can play a significant role in their depletion. Light-induced processes have been claimed to enhance transformation of these PM`s in the environment. However, detailed studies on the nature and identities of photoproducts formed during the transformation of these compounds on solid surfaces is scarce. Since insulators such as silica, alumina,silicoaluminates and calcium carbonate are believed to constitute up 20-30% of inorganic particulates present in the atmosphere, they serve as environmentally relevant model surfaces to study the photophysical and photochemical behavior of PM`s. Although photochemistry of organic compounds adsorbed on solid surfaces has received much attention in recent years, the specific properties of the interface which influence photoprocesses and the exact mechanism of interaction between a surface and a substrate are often not well understood. We have investigated the photochemistry of many PAHs including eight that are on Environmental Protection Agency`s (EPA) sixteen priority pollutant PAH list shown in Table 1 at silica/air interface.

  9. Sodium arsenite impairs insulin secretion and transcription in pancreatic {beta}-cells

    SciTech Connect (OSTI)

    Diaz-Villasenor, Andrea [Department of Genomic Medicine and Environmental Toxicology, Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico (Mexico); Sanchez-Soto, M. Carmen [Department of Biophysics, Instituto de Fisiologia Celular, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, A.P. 70-253 Coyoacan, Mexico D.F. 04510 (Mexico); Cebrian, Mariano E. [Section of Environmental Toxicology, CINVESTAV, IPN, Mexico City (Mexico); Ostrosky-Wegman, Patricia [Department of Genomic Medicine and Environmental Toxicology, Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico (Mexico); Hiriart, Marcia [Department of Biophysics, Instituto de Fisiologia Celular, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, A.P. 70-253 Coyoacan, Mexico D.F. 04510 (Mexico)]. E-mail: mhiriart@ifc.unam.mx

    2006-07-01T23:59:59.000Z

    Human studies have shown that chronic inorganic arsenic (iAs) exposure is associated with a high prevalence and incidence of type 2 diabetes. However, the mechanism(s) underlying this effect are not well understood, and practically, there is no information available on the effects of arsenic on pancreatic {beta}-cells functions. Thus, since insulin secreted by the pancreas plays a crucial role in maintaining glucose homeostasis, our aim was to determine if sodium arsenite impairs insulin secretion and mRNA expression in single adult rat pancreatic {beta}-cells. Cells were treated with 0.5, 1, 2, 5 and 10 {mu}M sodium arsenite and incubated for 72 and 144 h. The highest dose tested (10 {mu}M) decreased {beta}-cell viability, by 33% and 83%, respectively. Insulin secretion and mRNA expression were evaluated in the presence of 1 and 5 {mu}M sodium arsenite. Basal insulin secretion, in 5.6 mM glucose, was not significantly affected by 1 or 5 {mu}M treatment for 72 h, but basal secretion was reduced when cells were exposed to 5 {mu}M sodium arsenite for 144 h. On the other hand, insulin secretion in response to 15.6 mM glucose decreased with sodium arsenite in a dose-dependent manner in such a way that cells were no longer able to distinguish between different glucose concentrations. We also showed a significant decrease in insulin mRNA expression of cells exposed to 5 {mu}M sodium arsenite during 72 h. Our data suggest that arsenic may contribute to the development of diabetes mellitus by impairing pancreatic {beta}-cell functions, particularly insulin synthesis and secretion.

  10. Method of making a current collector for a sodium/sulfur battery

    DOE Patents [OSTI]

    Tischer, R.P.; Winterbottom, W.L.; Wroblowa, H.S.

    1987-03-10T23:59:59.000Z

    This specification is directed to a method of making a current collector for a sodium/sulfur battery. The current collector so-made is electronically conductive and resistant to corrosive attack by sulfur/polysulfide melts. The method includes the step of forming the current collector for the sodium/sulfur battery from a composite material formed of aluminum filled with electronically conductive fibers selected from the group of fibers consisting essentially of graphite fibers having a diameter up to 10 microns and silicon carbide fibers having a diameter in a range of 500--1,000 angstroms. 2 figs.

  11. Sodium and oxygen in Nigerian coals: Possible effects on ash fouling

    SciTech Connect (OSTI)

    Ewa, I.O.B.; Elegbe, S.B.; Adetunji, J. [Ahmadu Bello Univ., Zaria (Nigeria)

    1996-09-01T23:59:59.000Z

    Ash fouling during heat transfers in coal power-plants has been known to be an engineering problem caused by high sodium levels of the feed-coals. Instrumental Neutron Activation Analysis (INAA) was used in determining the concentration of some alkali elements (Na, Ca, Mg) associated with ash fouling for eight Nigerian coals mined at Onyeama, Ogbete, Enugu, Gombe, Okaba, Afikpo, Lafia and Asaba. Sodium levels were generally low (0.001-0.036%). Oxygen concentrations considered as an indicative measure of the wettability of each of the coals were determined. The possible effects of the concentration of these elements on ash fouling were discussed. 8 refs., 3 tabs.

  12. Method of making a current collector for a sodium/sulfur battery

    DOE Patents [OSTI]

    Tischer, Ragnar P. (Birmingham, MI); Winterbottom, Walter L. (Farmington Hills, MI); Wroblowa, Halina S. (West Bloomfield, MI)

    1987-01-01T23:59:59.000Z

    This specification is directed to a method of making a current collector (14) for a sodium/sulfur battery (10). The current collector so-made is electronically conductive and resistant to corrosive attack by sulfur/polysulfide melts. The method includes the step of forming the current collector for the sodium/sulfur battery from a composite material (16) formed of aluminum filled with electronically conductive fibers selected from the group of fibers consisting essentially of graphite fibers having a diameter up to 10 microns and silicon carbide fibers having a diameter in a range of 500-1000 angstroms.

  13. Draft Environmental Impact Statement for the Treatment and Management of Sodium-Bonded Spent Nuclear Fuel

    SciTech Connect (OSTI)

    N /A

    1999-07-30T23:59:59.000Z

    This document summarizes the U.S. Department of Energy's ''Draft Environmental Impact Statement for the Treatment and Management of Sodium-Bonded Spent Nuclear Fuel''. In addition to information concerning the background, purpose and need for the proposed action, and the National Environmental Policy Act process, this summary describes the characteristics of sodium-bonded spent nuclear fuel, the proposed treatment methods, the proposed facilities, the alternatives considered, and the environmental consequences of these alternatives. A glossary is included at the end to assist the reader with some of the technical terms used in this document.

  14. L-sodium lactate in cooked beef top rounds: differing levels of incorporation and cookery 

    E-Print Network [OSTI]

    Evans, Lori Leigh

    1992-01-01T23:59:59.000Z

    L-SODIUM LACTATE IN COOKED BEEF TOP ROUNDS; DIFFERING LEVELS OF INCORPORATION AND COOKERY A Thesis by LORI LEIGH EVANS Submitted to the Office of Graduate Studies of Texas A8 M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE May 1992 Major Subject: Animal Science L-SODIUM LACTATE IN COOKED BEEF TOP ROUNDS; DIFFERING LEVELS OF INCORPORATION AND COOKERY A Thesis by LORI LEIGH EVANS Approved as to style and content by: R. K. Miller (Chair...

  15. Preliminary analysis of patent trends for sodium/sulfur battery technology

    SciTech Connect (OSTI)

    Triplett, M.B.; Winter, C.; Ashton, W.B.

    1985-07-01T23:59:59.000Z

    This document summarizes development trends in sodium/sulfur battery technology based on data from US patents. Purpose of the study was to use the activity, timing and ownership of 285 US patents to identify and describe broad patterns of change in sodium/sulfur battery technology. The analysis was conducted using newly developed statistical and computer graphic techniques for describing technology development trends from patent data. This analysis suggests that for some technologies trends in patent data provide useful information for public and private R and D planning.

  16. Simplified modeling of liquid sodium medium with temperature and velocity gradient using real thermal-hydraulic data. Application to ultrasonic thermometry in sodium fast reactor

    SciTech Connect (OSTI)

    Massacret, N.; Jeannot, J. P. [DEN/DTN/STPA/LIET, CEA Cadarache, Saint Paul Lez Durance (France); Moysan, J.; Ploix, M. A.; Corneloup, G. [Aix-Marseille Univ, LMA UPR 7051 CNRS, site LCND, 13625 Aix-en-Provence (France)

    2013-01-25T23:59:59.000Z

    In the framework of the French R and D program for the Generation IV reactors and specifically for the sodium cooled fast reactors (SFR), studies are carried out on innovative instrumentation methods in order to improve safety and to simplify the monitoring of fundamental physical parameters during reactor operation. The aim of the present work is to develop an acoustic thermometry method to follow up the sodium temperature at the outlet of subassemblies. The medium is a turbulent flow of liquid sodium at 550 Degree-Sign C with temperature inhomogeneities. To understand the effect of disturbance created by this medium, numerical simulations are proposed. A ray tracing code has been developed with Matlab Copyright-Sign in order to predict acoustic paths in this medium. This complex medium is accurately described by thermal-hydraulic data which are issued from a simulation of a real experiment in Japan. The analysis of these results allows understanding the effects of medium inhomogeneities on the further thermometric acoustic measurement.

  17. Tin Anode for Sodium-Ion Batteries Using Natural Wood Fiber as a Mechanical Buffer and Electrolyte Reservoir

    E-Print Network [OSTI]

    Li, Teng

    Tin Anode for Sodium-Ion Batteries Using Natural Wood Fiber as a Mechanical Buffer and Electrolyte Information ABSTRACT: Sodium (Na)-ion batteries offer an attractive option for low cost grid scale storage due to the abundance of Na. Tin (Sn) is touted as a high capacity anode for Na-ion batteries with a high theoretical

  18. Nature and distribution of iron sites in a sodium silicate glass investigated by neutron diffraction and EPSR simulation

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Nature and distribution of iron sites in a sodium silicate glass investigated by neutron distributed in the silicate network and shares corner with silicate tetrahedra. The existence of a majority, such as the increase of the elastic modulus of sodium silicate glasses with increasing Fe-concentration. Our data

  19. F POWER MEASUREMENT FOR GENERATION IV SODIUM FAST R. COULON, S. NORMAND, M. MICHEL, L. BARBOT, T. DOMENECH,

    E-Print Network [OSTI]

    Boyer, Edmond

    .F-84500 Bollène, France. ABSTRACT The Phénix nuclear power plant has been a French Sodium Fast Reactor the research of power tagging agents. Then, simulation study has been done to evaluate measurability using high20 F POWER MEASUREMENT FOR GENERATION IV SODIUM FAST REACTORS R. COULON, S. NORMAND, M. MICHEL, L

  20. PHYSICAL REVIEW B 84, 054203 (2011) Electrical and thermal conductivity of liquid sodium from first-principles calculations

    E-Print Network [OSTI]

    Alfè, Dario

    2011-01-01T23:59:59.000Z

    and technological point of view. For example, it is used as coolant in fast-breeding nuclear reactors, and in heatPHYSICAL REVIEW B 84, 054203 (2011) Electrical and thermal conductivity of liquid sodium from first on the electrical and thermal conductivity of liquid sodium at 400 K, calculated using density functional theory

  1. Structure and hydrogen dynamics of pure and Ti-doped sodium alanate Jorge iguez,1,2

    E-Print Network [OSTI]

    Yildirim, Taner

    Structure and hydrogen dynamics of pure and Ti-doped sodium alanate Jorge Íñiguez,1,2 T. Yildirim,1, Honolulu, Hawaii 96822, USA (Received 2 June 2004; published 3 August 2004) We have studied the structure, energetics, and dynamics of pure and Ti-doped sodium alanate NaAlH4 , focusing on the possibility

  2. Simultaneous measurement of the surface temperature and the release of atomic sodium from a burning black liquor droplet

    SciTech Connect (OSTI)

    Saw, Woei L.; Nathan, Graham J. [Centre for Energy Technology, The University of Adelaide, SA 5006 (Australia); School of Mechanical Engineering, The University of Adelaide (Australia); Ashman, Peter J.; Alwahabi, Zeyad T. [Centre for Energy Technology, The University of Adelaide, SA 5006 (Australia); School of Chemical Engineering, The University of Adelaide (Australia); Hupa, Mikko [Process Chemistry Centre, Aabo Akademi, Biskopsgatan 8 FI-20500 Aabo (Finland)

    2010-04-15T23:59:59.000Z

    Simultaneous measurement of the concentration of released atomic sodium, swelling, surface and internal temperature of a burning black liquor droplet under a fuel lean and rich condition has been demonstrated. Two-dimensional two-colour optical pyrometry was employed to determine the distribution of surface temperature and swelling of a burning black liquor droplet while planar laser-induced fluorescence (PLIF) was used to assess the temporal release of atomic sodium. The key findings of these studies are: (i) the concentration of atomic sodium released during the drying and devolatilisation stages was found to be correlated with the external surface area; and (ii) the insignificant presence of atomic sodium during the char consumption stage shows that sodium release is suppressed by the lower temperature and by the high CO{sub 2} content in and around the particle. (author)

  3. Robust conductive mesoporous carbon?silica composite films with highly ordered and oriented orthorhombic structures from triblock-copolymer template co-assembly

    SciTech Connect (OSTI)

    Song, Lingyan; Feng, Dan; Campbell, Casey G.; Gu, Dong; Forster, Aaron M.; Yager, Kevin G.; Fredin, Nathaniel; Lee, Hae-Jeong; Jones, Ronald L.; Zhao, Dongyuan; Vogt, Bryan D. (AZU)

    2012-07-11T23:59:59.000Z

    In this work, we describe a facile approach to improve the robustness of conductive mesoporous carbon-based thin films by the addition of silica to the matrix through the triconstituent organic-inorganic-organic co-assembly of resol (carbon precursor) and tetraethylorthosilicate (silica precursor) with triblock-copolymer Pluronic F127. The pyrolysis of the resol-silica-pluronic F127 film yields a porous composite thin film with well-defined mesostructure. X-Ray diffraction (XRD), grazing incidence small angle X-ray scattering (GISAXS), and electron microscopy measurements indicate that the obtained carbon-based thin films have a highly ordered orthorhombic mesostructure (Fmmm) with uniform large pore size ({approx}3 nm). The orthorhombic mesostructure is oriented and the (010) plane is parallel to the silicon wafer substrate. The addition of silica to the matrix impacts the pore size, surface area, porosity, modulus and conductivity. For composite films with approximately 40 wt% silica, the conductivity is decreased by approximately an order of magnitude in comparison to a pure carbon mesoporous film, but the conductivity is comparable to typical printed carbon inks used in electrochemical sensing, {approx}10 S cm{sup -1}. The mechanical properties of these mesoporous silica-carbon hybrid films are similar to the pure carbon analogs with a Young's modulus between 10 GPa and 15 GPa, but the material is significantly more porous. Moreover, the addition of silica to the matrix appears to improve the adhesion of the mesoporous film to a silicon wafer. These mesoporous silica-carbon composite films have appropriate characteristics for use in sensing applications.

  4. Multipolar plasmon modes of sodium sphere: constrain on the minimal sphere radius

    E-Print Network [OSTI]

    Multipolar plasmon modes of sodium sphere: constrain on the minimal sphere radius Krystyna Kolwas-668 Warsaw, Poland ABSTRACT We re-examine the usual expectations for multipolar plasmon modes of a simple the complex eigenfrequencies of plasmon modes can be attributed to the sphere of size larger than the minimum

  5. Room-temperature stationary sodium-ion batteries for large-scale electric energy storage

    E-Print Network [OSTI]

    Wang, Wei Hua

    Room-temperature stationary sodium-ion batteries for large-scale electric energy storage Huilin Pan attention particularly in large- scale electric energy storage applications for renewable energy and smart storage system in the near future. Broader context With the rapid development of renewable energy sources

  6. Mechanism and kinetics of a sodium-driven bacterial flagellar motor

    E-Print Network [OSTI]

    Berry, Richard

    Mechanism and kinetics of a sodium-driven bacterial flagellar motor Chien-Jung Loa,b , Yoshiyuki potential difference. It consists of an 50-nm rotor and up to 10 independent stators anchored to the cell of electrical and chemical potential. All 25 torque­speed curves had the same concave-down shape as fully

  7. determines the number of sodium spikes fired per event by individual cells (Maruta

    E-Print Network [OSTI]

    Oertner, Thomas

    determines the number of sodium spikes fired per event by individual cells (Maruta et al., 2007; Mathy et al., 2009) and may thereby mediate the direction and speed of learning in Purkinje cells (Mathy, apparently even down to the level of electrical synapses of the infe- rior olive (Lefler et al., 2014; Mathy

  8. indirect study, coal was oxidatively de-graded with sodium dichromate and the

    E-Print Network [OSTI]

    Howat, Ian M.

    indirect study, coal was oxidatively de- graded with sodium dichromate and the esterified products- vestigators concluded (17, p. 380) that "thiophene derivatives must be indige- nous to coal." The direct XANES conmpounds yielded spectra that bore little resemblance to the coal spec- trum. For example, simulations

  9. Voltage, stability and diffusion barrier differences between sodium-ion and lithium-ion intercalation materials

    E-Print Network [OSTI]

    Ceder, Gerbrand

    Voltage, stability and diffusion barrier differences between sodium-ion and lithium-ion-ion systems. Introduction Rechargeable lithium-ion (Li-ion) batteries1­4 have become a mainstay of the digital), much research has targeted the development and optimization of lithium-ion batteries, in particular

  10. Behavioral/Systems/Cognitive Sodium and Calcium Current-Mediated Pacemaker Neurons

    E-Print Network [OSTI]

    Del Negro, Christopher A.

    Behavioral/Systems/Cognitive Sodium and Calcium Current-Mediated Pacemaker Neurons and Respiratory excitability, which is inconsistent with a pacemaker-essential mechanism of respiratory rhythmogenesis evaluate here in the mamma- lian respiratory network. The cellular mechanisms that underlie respiratory

  11. Effect of lasalocid sodium on rumen fermentation and digestion in sheep

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Effect of lasalocid sodium on rumen fermentation and digestion in sheep P. THIVEND, J.-P. JOUANY Laboratoire de la Digestion des Ruminants, 1. N. R. A., Theix, 63122 Ceyrat France. Summary. Four adult sheep had taken place in the rumen bacterial population (table 3). Overall digestive utilization of organic

  12. Hazard categorization and baseline documentation for the Sodium Storage Facility. Revision 1

    SciTech Connect (OSTI)

    Bowman, B.R.

    1995-06-16T23:59:59.000Z

    Hazard Categorization evaluation has been performed in accordance with DOE-STD-1027 for the Sodium Storage Facility at FFTF and a determination of less than Category 3 or non-nuclear has been made. Hazard Baseline Documentation has been performed in accordance with DOE-EM-STD-5502 and a determination of ``Radiological Facility`` has been made.

  13. Development of an improved sodium exposure test cell experiment for characterization of AMTEC electrode performance

    E-Print Network [OSTI]

    Fiebig, Bradley Nelson

    1999-01-01T23:59:59.000Z

    are attached to each electrode band and tltreaded through electricaHy insulated feedthroughs at the flange, Thermocouples are placed at the hot end of the chamber and in the sodium pool. Figure 4. 'rhe electrode test sample with connecting leads in an SETC...

  14. The sodium tail of the Moon M. Matta a,b,*, S. Smith a,1

    E-Print Network [OSTI]

    Mendillo, Michael

    The sodium tail of the Moon M. Matta a,b,*, S. Smith a,1 , J. Baumgardner a,1 , J. Wilson a,1 , C was discovered soon after the 1998 Leonid meteor shower (Smith et al., 1999). On 19 November 1998, an all

  15. Predictors and outcome impact of perioperative serum sodium changes in a high risk population

    E-Print Network [OSTI]

    Klinck, J.; McNeill, L.; Di Angelantonio, E.; Menon, D.

    2014-01-01T23:59:59.000Z

    1 Predictors and outcome impact of perioperative serum sodium changes in a high risk population J Klinck 1 L McNeill 1 E Di Angelantonio 2 D Menon 1 1 Division of Perioperative Care, Box 93, Addenbrooke’s Hospital, Hills...

  16. Atomic-Layer-Deposition Oxide Nanoglue for Sodium Ion Batteries Xiaogang Han,,

    E-Print Network [OSTI]

    Li, Teng

    Atomic-Layer-Deposition Oxide Nanoglue for Sodium Ion Batteries Xiaogang Han,, Yang Liu,, Zheng Jia ABSTRACT: Atomic-layer-deposition (ALD) coatings have been increasingly used to improve battery performance/discharging. Battery tests in coin-cells further showed the ALD-Al2O3 coating remarkably boosts the cycling performance

  17. Ice iron/sodium film as cause for high noctilucent cloud radar reflectivity

    E-Print Network [OSTI]

    Bellan, Paul M.

    Ice iron/sodium film as cause for high noctilucent cloud radar reflectivity P. M. Bellan1 Received] Noctilucent clouds, tiny cold electrically charged ice grains located at about 85 km altitude, exhibit by assuming the ice grains are coated by a thin metal film; substantial evidence exists indicating

  18. Chemistry of Petroleum Crude Oil Deposits: Sodium Naphthenates 2009 NHMFL Science Highlight for NSF

    E-Print Network [OSTI]

    Weston, Ken

    Chemistry of Petroleum Crude Oil Deposits: Sodium Naphthenates 2009 NHMFL Science Highlight for NSF DMR-Award 0654118 Ion Cyclotron Resonance User Program Solid deposits and emulsions from crude oil can that contain carbons, hydrogens, and two oxygen atoms. #12;A major problem in oil production, both

  19. Equilibrium diagrams at 27 [degree]C of the water + sodium tungstate + dodecylamine chloride system

    SciTech Connect (OSTI)

    Dantas Neto, A.A.; Castro Dantas, T.N. de; Duarte, M.M.L.; Avelino, S. (Univ. Federal do Rio Grande do Norte, Natal (Brazil). Programa de Pos-Graduacao em Engenharia Quimica)

    1993-01-01T23:59:59.000Z

    Amines are usually used in extracting tungsten from scheelite. Dodecylamine chloride in kerosene and octanol was used as an extracting agent in order to establish the phase diagram at 27C for water + sodium tungstate + dodecylamine chloride. Acetone was used to prevent emulsion formation. This procedure made it possible to achieve better partition coefficients; however, there appears to be a saturation region.

  20. Original article Increased late sodium current in myocytes from a canine heart failure

    E-Print Network [OSTI]

    Kamp, Tim

    Original article Increased late sodium current in myocytes from a canine heart failure model and from failing human heart Carmen R. Valdivia, William W. Chu, Jielin Pu 1 , Jason D. Foell, Robert A December 2004 Abstract Electrophysiological remodeling of ion channels in heart failure causes action

  1. Sodium shortage as a constraint on the carbon cycle in an inland tropical rainforest

    E-Print Network [OSTI]

    Kaspari, Mike

    Sodium shortage as a constraint on the carbon cycle in an inland tropical rainforest Michael- composition of pure cellulose by up to 50%, compared with stream water alone. These effects emerged after 134). We provide experimental evidence that Na shortage slows the carbon cycle. Because 80% of global

  2. ALZHEIMER'S AMYLOID-BETA PEPTIDE INHIBITS SODIUM/CALCIUM EXCHANGE MEASURED IN RAT AND

    E-Print Network [OSTI]

    ALZHEIMER'S AMYLOID-BETA PEPTIDE INHIBITS SODIUM/CALCIUM EXCHANGE MEASURED IN RAT AND HUMAN BRAIN-beta1­40 (A 1­40) and A 25­35 reduced vesicular Ca2+ content. Both peptides produced a maximal reduction in Ca2+ content of approximately 50%. The peptides reduced Ca2+ content with similar potency and half

  3. Review of FY 2001 Development Work for Vitrification of Sodium Bearing Waste

    SciTech Connect (OSTI)

    Taylor, Dean Dalton; Barnes, Charles Marshall

    2002-09-01T23:59:59.000Z

    Treatment of sodium-bearing waste (SBW) at the Idaho Nuclear Technology and Engineering Center (INTEC) within the Idaho National Engineering and Environmental Laboratory is mandated by the Settlement Agreement between the Department of Energy and the State of Idaho. This report discusses significant findings from vitrification technology development during 2001 and their impacts on the design basis for SBW vitrification.

  4. Effects of amounts and types of sodium bicarbonate in wheat flour tortillas

    E-Print Network [OSTI]

    Garza Casso, Jessica Beatriz

    2007-04-25T23:59:59.000Z

    with slower acting acids (van Wazer 1961). Fast acting acids are used as a leavener themselves (Le Baw 1982). 11 The chemical reactions of leavening acids that will be used in this study are as follows: 1) Sodium aluminum sulfate (SAS), NaAl (SO 4 ) 2...

  5. Effects of Sodium Chloride Particles, Ozone, UV, and Relative Humidity on Atmospheric Corrosion of Silver

    E-Print Network [OSTI]

    Effects of Sodium Chloride Particles, Ozone, UV, and Relative Humidity on Atmospheric Corrosion The corrosion of Ag contaminated with NaCl particles in gaseous environments containing humidity and ozone analyzed using a coulometric reduction technique. The atmospheric corrosion of Ag was greatly accelerated

  6. CARACTRISTIQUES SPECTROSCOPIQUES DES TTRABENZOYLACTONATES-SODIUM D'EUROPIUM ET DE TERBIUM

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    415 CARACTÉRISTIQUES SPECTROSCOPIQUES DES TÉTRABENZOYLACÉTONATES-SODIUM D'EUROPIUM ET DE TERBIUM des ions d'europium, terbium ou lanthane. On étudie les différentes transitions moléculaires et caractéristiques du chélate d'europium qui a donné l'effet laser. Abstract. 2014 A four-ligand rare-earth chelate

  7. Effect of Sodium Carboxymethyl Celluloses on Water-catalyzed Self-degradation of 200-degree C-heated Alkali-Activated Cement

    SciTech Connect (OSTI)

    Sugama T.; Pyatina, T.

    2012-05-01T23:59:59.000Z

    We investigated the usefulness of sodium carboxymethyl celluloses (CMC) in promoting self-degradation of 200°C-heated sodium silicate-activated slag/Class C fly ash cementitious material after contact with water. CMC emitted two major volatile compounds, CO2 and acetic acid, creating a porous structure in cement. CMC also reacted with NaOH from sodium silicate to form three water-insensitive solid reaction products, disodium glycolate salt, sodium glucosidic salt, and sodium bicarbonate. Other water-sensitive solid reaction products, such as sodium polysilicate and sodium carbonate, were derived from hydrolysates of sodium silicate. Dissolution of these products upon contact with water generated heat that promoted cement’s self-degradation. Thus, CMC of high molecular weight rendered two important features to the water-catalyzed self-degradation of heated cement: One was the high heat energy generated in exothermic reactions in cement; the other was the introduction of extensive porosity into cement.

  8. Conceptual Design of a MEDE Treatment System for Sodium Bonded Fuel

    SciTech Connect (OSTI)

    Carl E. Baily; Karen A. Moore; Collin J. Knight; Peter B. Wells; Paul J. Petersen; Ali S. Siahpush; Matthew T. Weseman

    2008-05-01T23:59:59.000Z

    Unirradiated sodium bonded metal fuel and casting scrap material containing highly enriched uranium (HEU) is stored at the Materials and Fuels Complex (MFC) on the Idaho National Laboratory (INL). This material, which includes intact fuel assemblies and elements from the Fast Flux Test Facility (FFTF) and Experimental Breeder Reactor-II (EBR-II) reactors as well as scrap material from the casting of these fuels, has no current use under the terminated reactor programs for both facilities. The Department of Energy (DOE), under the Sodium-Bonded Spent Nuclear Fuel Treatment Record of Decision (ROD), has determined that this material could be prepared and transferred to an off-site facility for processing and eventual fabrication of fuel for commercial nuclear reactors. A plan is being developed to prepare, package and transfer this material to the DOE High Enriched Uranium Disposition Program Office (HDPO), located at the Y-12 National Security Complex in Oak Ridge, Tennessee. Disposition of the sodium bonded material will require separating the elemental sodium from the metallic uranium fuel. A sodium distillation process known as MEDE (Melt-Drain-Evaporate), will be used for the separation process. The casting scrap material needs to be sorted to remove any foreign material or fines that are not acceptable to the HDPO program. Once all elements have been cut and loaded into baskets, they are then loaded into an evaporation chamber as the first step in the MEDE process. The chamber will be sealed and the pressure reduced to approximately 200 mtorr. The chamber will then be heated as high as 650 ºC, causing the sodium to melt and then vaporize. The vapor phase sodium will be driven into an outlet line where it is condensed and drained into a receiver vessel. Once the evaporation operation is complete, the system is de-energized and returned to atmospheric pressure. This paper describes the MEDE process as well as a general overview of the furnace systems, as necessary, to complete the MEDE process.

  9. Final Environmental Impact Statement for the Treatment and Management of Sodium-Bonded Spent Nuclear Fuel

    SciTech Connect (OSTI)

    N /A

    2000-08-04T23:59:59.000Z

    DOE is responsible for the safe and efficient management of its sodium-bonded spent nuclear fuel. This fuel contains metallic sodium, a highly reactive material; metallic uranium, which is also reactive; and in some cases, highly enriched uranium. The presence of reactive materials could complicate the process of qualifying and licensing DOE's sodium-bonded spent nuclear fuel inventory for disposal in a geologic repository. Currently, more than 98 percent of this inventory is located at the Idaho National Engineering and Environmental Laboratory (INEEL), near Idaho Falls, Idaho. In addition, in a 1995 agreement with the State of Idaho, DOE committed to remove all spent nuclear fuel from Idaho by 2035. This EIS evaluates the potential environmental impacts associated with the treatment and management of sodium-bonded spent nuclear fuel in one or more facilities located at Argonne National Laboratory-West (ANL-W) at INEEL and either the F-Canyon or Building 105-L at the Savannah River Site (SRS) near Aiken, South Carolina. DOE has identified and assessed six proposed action alternatives in this EIS. These are: (1) electrometallurgical treatment of all fuel at ANL-W, (2) direct disposal of blanket fuel in high-integrity cans with the sodium removed at ANL-W, (3) plutonium-uranium extraction (PUREX) processing of blanket fuel at SRS, (4) melt and dilute processing of blanket fuel at ANL-W, (5) melt and dilute processing of blanket fuel at SRS, and (6) melt and dilute processing of all fuel at ANL-W. In addition, Alternatives 2 through 5 include the electrometallurgical treatment of driver fuel at ANL-W. Under the No Action Alternative, the EIS evaluates both the continued storage of sodium-bonded spent nuclear fuel until the development of a new treatment technology or direct disposal without treatment. Under all of the alternatives, the affected environment is primarily within 80 kilometers (50 miles) of spent nuclear fuel treatment facilities. Analyses indicate little difference in the environmental impacts among alternatives. DOE has identified electrometallurgical treatment as its Preferred Alternative for the treatment and management of all sodium-bonded spent nuclear fuel, except for the Fermi-1 blanket fuel. The No Action Alternative is preferred for the Fermi-1 blanket spent nuclear fuel.

  10. Silane Modification of Glass and Silica Surfaces to Obtain Equally Oil-Wet Surfaces in Glass-Covered Silicon Micromodel Applications

    SciTech Connect (OSTI)

    Grate, Jay W.; Warner, Marvin G.; Pittman, Jonathan W.; Dehoff, Karl J.; Wietsma, Thomas W.; Zhang, Changyong; Oostrom, Martinus

    2013-08-05T23:59:59.000Z

    The wettability of silicon and glass surfaces can be modified by silanization. However, similar treatments of glass and silica surfaces using the same silane do not necessarily yield the same wettability as determined by the oil-water contact angle. In this technical note, surface cleaning pretreatments were investigated to determine conditions that would yield oil-wet surfaces on glass with similar wettability to silica surfaces treated with the same silane, and both air-water and oil-water contact angles were determined. Air-water contact angles were less sensitive to differences between silanized silica and glass surfaces, often yielding similar values while the oil-water contact angles were quite different. Borosilicate glass surfaces cleaned with standard cleaning solution 1 (SC1) yield intermediate-wet surfaces when silanized with hexamethyldisilazane, while the same cleaning and silanization yields oil-wet surfaces on silica. However, cleaning glass in boiling concentrated nitric acid creates a surface that can be silanized to obtain oil-wet surfaces using HDMS. Moreover, this method is effective on glass with prior thermal treatment at an elevated temperature of 400oC. In this way, silica and glass can be silanized to obtain equally oil-wet surfaces using HMDS. It is demonstrated that pretreatment and silanization is feasible in silicon-silica/glass micromodels previously assembled by anodic bonding, and that the change in wettability has a significant observable effect on immiscisble fluid displacements in the pore network.

  11. Analysis of micro-structural relaxation phenomena in laser-modified fused silica using confocal Raman microscopy

    SciTech Connect (OSTI)

    Matthews, M; Vignes, R; Cooke, J; Yang, S; Stolken, J

    2009-12-15T23:59:59.000Z

    Fused silica micro-structural changes associated with localized 10.6 {micro}m CO{sub 2} laser heating are reported. Spatially-resolved shifts in the high-frequency asymmetric stretch transverse-optic (TO) phonon mode of SiO{sub 2} were measured using confocal Raman microscopy, allowing construction of axial fictive temperature (T{sub f}) maps for various laser heating conditions. A Fourier conduction-based finite element model was employed to compute on-axis temperature-time histories, and, in conjunction with a Tool-Narayanaswamy form for structural relaxation, used to fit T{sub f}(z) profiles to extract relaxation parameters. Good agreement between the calculated and measured T{sub f} was found, yielding reasonable values for relaxation time and activation enthalpy in the laser-modified silica.

  12. The effects of surface chemistry of mesoporous silica materials and solution pH on kinetics of molsidomine adsorption

    SciTech Connect (OSTI)

    Dolinina, E.S.; Parfenyuk, E.V., E-mail: terrakott37@mail.ru

    2014-01-15T23:59:59.000Z

    Adsorption kinetics of molsidomine on mesoporous silica material (UMS), the phenyl- (PhMS) and mercaptopropyl-functionalized (MMS) derivatives from solution with different pH and 298 K was studied. The adsorption kinetics was found to follow the pseudo-second-order kinetic model for all studied silica materials and pH. Effects of surface functional groups and pH on adsorption efficiency and kinetic adsorption parameters were investigated. At all studied pH, the highest molsidomine amount is adsorbed on PhMS due to ?–? interactions and hydrogen bonding between surface groups of PhMS and molsidomine molecules. An increase of pH results in a decrease of the amounts of adsorbed molsidomine onto the silica materials. Furthermore, the highest adsorption rate kinetically evaluated using a pseudo-second-order model, is observed onto UMS and it strongly depends on pH. The mechanism of the adsorption process was determined from the intraparticle diffusion and Boyd kinetic film–diffusion models. The results showed that the molsidomine adsorption on the silica materials is controlled by film diffusion. Effect of pH on the diffusion parameters is discussed. - Graphical abstract: The kinetic study showed that the k{sub 2} value, the rate constant of pseudo-second order kinetic model, is the highest for molsidomine adsorption on UMS and strongly depends on pH because it is determined by availability and accessibility of the reaction sites of the adsorbents molsidomine binding. Display Omitted - Highlights: • The adsorption capacities of UMS, PhMS and MMS were dependent on the pH. • At all studied pH, the highest molsidomine amount is adsorbed on PhMS. • The highest adsorption rate, k{sub 2}, is observed onto UMS and strongly depends on pH. • Film diffusion was the likely rate-limiting step in the adsorption process.

  13. Enlargement of Grains of Silica Colloidal Crystals by Centrifugation in an Inverted-Triangle Internal-Shaped Container

    E-Print Network [OSTI]

    Kaori Hashimoto; Atsushi Mori; Katsuhiro Tamura; Yoshihisa Suzuki

    2013-01-30T23:59:59.000Z

    We successfully fabricated large grains of silica colloidal crystals in an inverted-triangle internal-shaped container (inverted-triangle container) by centrifugation. The largest grain in the container was much larger than that in a container which has a flat bottom and constant width (flat-bottomed container). The edged bottom of the inverted-triangle container eliminated the number of the grains, and then the broadened shape of the container effectively widened the grains.

  14. BIMETALLIC NANOCATALYSTS IN MESOPOROUS SILICA FOR HYDROGEN PRODUCTION FROM COAL-DERIVED FUELS

    SciTech Connect (OSTI)

    Kuila, Debasish; Ilias, Shamsuddin

    2013-02-13T23:59:59.000Z

    In steam reforming reactions (SRRs) of alkanes and alcohols to produce H{sub 2}, noble metals such as platinum (Pt) and palladium (Pd) are extensively used as catalyst. These metals are expensive; so, to reduce noble-metal loading, bi-metallic nanocatalysts containing non-noble metals in MCM-41 (Mobil Composition of Material No. 41, a mesoporous material) as a support material with high-surface area were synthesized using one-pot hydrothermal procedure with a surfactant such as cetyltrimethylammonium bromide (CTAB) as a template. Bi-metallic nanocatalysts of Pd-Ni and Pd-Co with varying metal loadings in MCM-41 were characterized by x-ray diffraction (XRD), N{sub 2} adsorption, and Transmission electron microscopy (TEM) techniques. The BET surface area of MCM-41 (~1000 m{sup 2}/g) containing metal nanoparticles decreases with the increase in metal loading. The FTIR studies confirm strong interaction between Si-O-M (M = Pd, Ni, Co) units and successful inclusion of metal into the mesoporous silica matrix. The catalyst activities were examined in steam reforming of methanol (SRM) reactions to produce hydrogen. Reference tests using catalysts containing individual metals (Pd, Ni and Co) were also performed to investigate the effect of the bimetallic system on the catalytic behavior in the SRM reactions. The bimetallic system remarkably improves the hydrogen selectivity, methanol conversion and stability of the catalyst. The results are consistent with a synergistic behavior for the Pd-Ni-bimetallic system. The performance, durability and thermal stability of the Pd-Ni/MCM-41 and Pd-Co/MCM-41 suggest that these materials may be promising catalysts for hydrogen production from biofuels. A part of this work for synthesis and characterization of Pd-Ni-MCM-41 and its activity for SRM reactions has been published (“Development of Mesoporous Silica Encapsulated Pd-Ni Nanocatalyst for Hydrogen Production” in “Production and Purification of Ultraclean Transportation Fuels”; Hu, Y., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 2011.)

  15. Assimilation and respiration of radioactive ethylene glycol, in the presence of high sodium chloride concentrations, by a sodium chloride requiring bacterium

    E-Print Network [OSTI]

    Gonzalez, Carlos Francisco

    1972-01-01T23:59:59.000Z

    and the contents distilled over into 5 ml of a 2X boric acid solution containing 3 ml of a O. l%%d ethanolic solution of methyl red and 5. 7 ml of a 0. 1X ethanolic 29 solution of brom cresol green. The samples were titrated, with 0. 1N HC1 using a... limits. Sodium requirement Effect of pH on growth Utilization of carbon sources. Respiration studies. Quantitation of ethylene glycol carbon Disappearance of. glucose and ammonia-nitrogen from cultures of Bacterium T-52. Possible pathways...

  16. Liquid-Metal Electrode to Enable Ultra-Low Temperature Sodium-Beta Alumina Batteries for Renewable Energy Storage

    SciTech Connect (OSTI)

    Lu, Xiaochuan; Li, Guosheng; Kim, Jin Yong; Mei, Donghai; Lemmon, John P.; Sprenkle, Vincent L.; Liu, Jun

    2014-08-01T23:59:59.000Z

    Metal electrodes have a high capacity for energy storage but have found limited applications in batteries because of dendrite formation and other problems. In this paper, we report a new alloying strategy that can significantly reduce the melting temperature and improve wetting with the electrolyte to allow the use of liquid metal as anode in sodium-beta alumina batteries (NBBs) at much lower temperatures (e.g., 95 to 175°C). Commercial NBBs such as sodium-sulfur (Na-S) battery and sodium-metal halide (ZEBRA) batteries typically operate at relatively high temperatures (e.g., 300-350°C) due to poor wettability of sodium on the surface of ?"-Al2O3. Our combined experimental and computational studies suggest that Na-Cs alloy can replace pure sodium as the anode material, which provides a significant improvement in wettability, particularly at lower temperatures (i.e., <200°C). Single cells with the Na-Cs alloy anode exhibit excellent cycling life over those with pure sodium anode at 175 and 150°C. The cells can even operate at 95°C, which is below the melting temperature of pure sodium. These results demonstrate that NBB can be operated at ultra lower temperatures with successfully solving the wetting issue. This work also suggests a new strategy to use liquid metal as the electrode materials for advanced batteries that can avoid the intrinsic safety issues associated with dendrite formation on the anode.

  17. Tuning the properties of Ge-quantum dots superlattices in amorphous silica matrix through deposition conditions

    SciTech Connect (OSTI)

    Pinto, S. R. C.; Ramos, M. M. D.; Gomes, M. J. M. [University of Minho, Centre of Physics and Physics Department, Braga 4710-057 (Portugal); Buljan, M. [Ruder Boskovic Institute, Bijenicka cesta 54, Zagreb 10000 (Croatia); Chahboun, A. [University of Minho, Centre of Physics and Physics Department, Braga 4710-057 (Portugal); Physics Department, FST Tanger, Tanger BP 416 (Morocco); Roldan, M. A.; Molina, S. I. [Departamento de Ciencia de los Materiales e Ing. Metalurgica y Q. I., Universidad de Cadiz, Cadiz (Spain); Bernstorff, S. [Sincrotrone Trieste, SS 14 km163, 5, Basovizza 34012 (Italy); Varela, M.; Pennycook, S. J. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Barradas, N. P.; Alves, E. [Instituto Superior Tecnico e Instituto Tecnologico e Nuclear-, EN10, Sacavem 2686-953 (Portugal)

    2012-04-01T23:59:59.000Z

    In this work, we investigate the structural properties of Ge quantum dot lattices in amorphous silica matrix, prepared by low-temperature magnetron sputtering deposition of (Ge+SiO{sub 2})/SiO{sub 2} multilayers. The dependence of quantum dot shape, size, separation, and arrangement type on the Ge-rich (Ge + SiO{sub 2}) layer thickness is studied. We show that the quantum dots are elongated along the growth direction, perpendicular to the multilayer surface. The size of the quantum dots and their separation along the growth direction can be tuned by changing the Ge-rich layer thickness. The average value of the quantum dots size along the lateral (in-plane) direction along with their lateral separation is not affected by the thickness of the Ge-rich layer. However, the thickness of the Ge-rich layer significantly affects the quantum dot ordering. In addition, we investigate the dependence of the multilayer average atomic composition and also the quantum dot crystalline quality on the deposition parameters.

  18. Tuning the properties of Ge-quantum dots superlattices in amorphous silica matrix through deposition conditions

    SciTech Connect (OSTI)

    Pinto, S. [University of Minho, Portugal; Roldan Gutierrez, Manuel A [ORNL; Ramos, M. M.D. [University of Minho, Portugal; Gomes, M.J.M. [University of Minho, Portugal; Molina, S. I. [Universidad de Cadiz, Spain; Pennycook, Stephen J [ORNL; Varela del Arco, Maria [ORNL; Buljan, M. [R. Boskovic Institute, Zagreb, Croatia; Barradas, N. [Instituto Tecnologico e Nuclear (ITN), Lisbon, Portugal; Alves, E. [Instituto Tecnologico e Nuclear (ITN), Lisbon, Portugal; Chahboun, A. [FST Tanger, Morocco; Bernstorff, S. [Sincrotrone Trieste, Basovizza, Italy

    2012-01-01T23:59:59.000Z

    In this work, we investigate the structural properties of Ge quantum dot lattices in amorphous silica matrix, prepared by low-temperature magnetron sputtering deposition of (Ge+SiO{sub 2})/SiO{sub 2} multilayers. The dependence of quantum dot shape, size, separation, and arrangement type on the Ge-rich (Ge + SiO{sub 2}) layer thickness is studied. We show that the quantum dots are elongated along the growth direction, perpendicular to the multilayer surface. The size of the quantum dots and their separation along the growth direction can be tuned by changing the Ge-rich layer thickness. The average value of the quantum dots size along the lateral (in-plane) direction along with their lateral separation is not affected by the thickness of the Ge-rich layer. However, the thickness of the Ge-rich layer significantly affects the quantum dot ordering. In addition, we investigate the dependence of the multilayer average atomic composition and also the quantum dot crystalline quality on the deposition parameters.

  19. Interfacial Modification of Silica Surfaces Through gamma-Isocyanatopropyl Triethoxy Silane-Amine Coupling Reactions

    SciTech Connect (OSTI)

    Vogel,B.; DeLongchamp, D.; Mahoney, C.; Lucas, L.; Fischer, D.; Lin, E.

    2008-01-01T23:59:59.000Z

    The development of robust, cost-effective methods to modify surfaces and interfaces without the specialized synthesis of unique coupling agents could provide readily accessible routes to optimize and tailor interfacial properties. We demonstrate that -isocyanatopropyl triethoxysilane (ISO) provides a convenient route to functionalize silica surfaces through coupling reactions with readily available reagents. ISO coupling agents layers (CALs) can be prepared from toluene with triethylamine (TEA), but the coupling reaction of an amine to the ISO CAL does not proceed. We use near edge X-ray absorption fine structure (NEXAFS), time-of-flight secondary ion mass spectrometry (TOF-SIMS) and sessile drop contact angle to demonstrate the isocyanate layer is not degraded under coupling conditions. Access to silanes with chemical functionality is possible with ISO by performing the coupling reaction in solution and then depositing the product onto the surface. Two model CAL surfaces are prepared to demonstrate the ease and robust nature of this procedure. The surfaces prepared using this method are the ISO reacted with octadecylamine to produce a hydrocarbon surface of similar quality to octadecyl trichlorosilane (OTS) CALs and with 9-aminofluorene (AFL), an aromatic amine functionality whose silane is otherwise unavailable commercially.

  20. Dynamics of femtosecond laser absorption of fused silica in the ablation regime

    SciTech Connect (OSTI)

    Lebugle, M., E-mail: lebugle@lp3.univ-mrs.fr; Sanner, N.; Varkentina, N.; Sentis, M.; Utéza, O. [Aix Marseille Université, CNRS, LP3 UMR 7341, 13288 Marseille (France)

    2014-08-14T23:59:59.000Z

    We investigate the ultrafast absorption dynamics of fused silica irradiated by a single 500?fs laser pulse in the context of micromachining applications. A 60-fs-resolution pump-probe experiment that measures the reflectivity and transmissivity of the target under excitation is developed to reveal the evolution of plasma absorption. Above the ablation threshold, an overcritical plasma with highly non-equilibrium conditions is evidenced in a thin layer at the surface. The maximum electron density is reached at a delay of 0.5?ps after the peak of the pump pulse, which is a strong indication of the occurrence of electronic avalanche. The results are further analyzed to determine the actual feedback of the evolution of the optical properties of the material on the pump pulse. We introduce an important new quantity, namely, the duration of absorption of the laser by the created plasma, corresponding to the actual timespan of laser absorption by inverse Bremsstrahlung. Our results indicate an increasing contribution of plasma absorption to the total material absorption upon raising the excitation fluence above the ablation threshold. The role of transient optical properties during the energy deposition stage is characterized and our results emphasize the necessity to take it into account for better understanding and control of femtosecond laser-dielectrics interaction.

  1. Microstructural characterization of low-density foams. [Silica, resorcinol/formaldehyde, cellulose/acetate

    SciTech Connect (OSTI)

    Price, C.W.

    1988-01-01T23:59:59.000Z

    Low-density foams (of the order 0.1 g/cm/sup 3/) synthesized from silica aerogel, resorcinol/formaldehyde, and cellulose acetate have fine, delicate microstructures that are extremely difficult to characterize. Improved low-voltage resolution of an SEM equipped with a field-emission gun (FESEM) does permit these materials to be examined directly without coating and at sufficient magnification to reveal the microstructures. Light coatings applied by ion-beam deposition can stabilize the specimens to some extent and reduce electron charging without seriously altering the microstructure, but coatings applied by conventional techniques usually obliterate these microstructures. Transmission electron microscopy (TEM) is required to provide unambiguous microstructural interpretations. However, TEM examinations of these materials can be severely restricted by specimen preparation difficulties and electron-beam damage, and considerable care must be taken to ensure that reasonably accurate TEM results have been obtained. This work demonstrates that low-voltage FESEM analyses can be used to characterize microstructures in these foams, but TEM analyses are required to confirm the FESEM analyses and perform quantitative measurements. 19 refs., 11 figs.

  2. Luminescence of silicon dioxide different polymorph modification: Silica glass, ?-quartz, stishovite, coesite

    SciTech Connect (OSTI)

    Trukhin, A. N., E-mail: truhins@cfi.lu.lv [Institute of Solid State Physics, University of Latvia, LV-1063 Riga (Latvia)

    2014-10-21T23:59:59.000Z

    Stishovite, coesite, oxygen deficient silica glass as well as irradiated ?-quartz, exhibit two luminescence bands: a blue one and an UV one both excitable in the range within optical gap. There are similarities in spectral position and in luminescence decay kinetics among centers in these materials. The interpretation was done on the model of Oxygen Deficient Centers (ODC) [1]. The ODC(II) or twofold coordinated silicon and ODC(I) are distinguished. ODC(I) is object of controversial interpretation. The Si-Si oxygen vacancy [2] and complex defect including latent twofold coordinated silicon [3] are proposed. Remarkably, this luminescence center does not exist in as grown crystalline ?-quartz. However, destructive irradiation of ?-quartz crystals with fast neutrons, ? rays, or dense electron beams [4–6] creates ODC(I) like defect. In tetrahedron structured coesite the self trapped exciton (STE) luminescence observed with high energetic yield (?30%) like in ?-quartz crystals. STE in coesite coexists with oxygen deficient-like center. In octahedron structured stishovite STE was not found and only ODC exists.

  3. Preconcentration of uranium in seawater with heterocyclic azo dyes supported on silica gel

    SciTech Connect (OSTI)

    Ueda, K.; Koshino, Y.; Yamamoto, Y.

    1985-11-01T23:59:59.000Z

    The chelating adsorbents, heterocyclic azo dyes supported on silica gel, were prepared and their adsorption behaviors of metal ions were investigated. The 1-(2-pyridylazo)-2-naphthol(PAN)-SG and 2-(2-thiazolylazo)-p-cresol(TAC)-SG show greater affinity for UO/sub 2/(II) and ZrO(II), compared with the other metal ions like Cu, Cd, Fe and alkaline earths. Trace uranyl can be quantitatively retained on the column of the gels at neutral pH region and flowrate 3-4 ml/min. The uranyl retained is easily eluted from the column bed with a mixture of acetone and nitric acid (9:1 v/v) and determined by spectrophotometry using Arsenazo-III. Matrix components in seawater do not interfere and the spiked recovery of uranyl in artificial seawater was found to be average 98.6%, with the relative standard deviation of 1.08%. Both gels were applied to the determination of uranium in seawater with satisfactory results. 16 references, 3 figures, 3 tables.

  4. A New Concept for the Fabrication of Hydrogen Selective Silica Membranes

    SciTech Connect (OSTI)

    Michael Tsapatsis

    2005-10-01T23:59:59.000Z

    It is attempted to synthesize hydrogen selective silica-based membranes through a novel thin film deposition concept. This report describes the progress made during the 1st Year of this award. All project Tasks, for Year 1, were completed and the first thin films were prepared and characterized. The goal of this work is to use crystalline layered silicates to form hydrogen selective membranes for use in high temperature hydrogen/carbon dioxide separations. It was proposed to: (A) Synthesize layered silicate materials; (B) Prepare dispersions of as synthesized or delaminated layered silicates; (C) Prepare membranes by coating the layered silicates on macro-mesoporous supports; and (D) Test the membranes for H{sub 2}/CO{sub 2} selectivity at high temperature and pressures and for structural and functional stability at high temperature in the presence of water vapor. All Year 1 project Tasks are completed. Layered silicate particles were synthesized hydrothermally. Crystal shape and size was optimized for the formation of thin films. Calcination procedures that avoid particle agglomeration were developed and suspensions of the calcined silicate particles were prepared. The silicate particles and suspensions were characterized by X-Ray Diffraction, Electron Microscopy and Dynamic Light Scattering. The characterization data indicate that plate like morphology, large aspect ratio and good dispersion have been achieved. A deposition process that leads to uniform, high-coverage ({approx}100%) coating of the layered silicate particles on porous alpha-alumina supports was developed.

  5. Morphologies of laser-induced damage in hafnia-silica multilayer mirror and polarizer coatings

    SciTech Connect (OSTI)

    Genin, F.Y.; Stolz, C.J.

    1996-08-01T23:59:59.000Z

    Hafnium-silica multilayer mirrors and polarizers were deposited by e-beam evaporation onto BK7 glass substrates. The mirrors and polarizers were coated for operation at 1053 nm at 45{degree} and at Brewster`s angle (56{degree}), respectively. They were tested with a single 3-ns laser pulse. Morphology of the laser-induced damage was characterized by optical and scanning electron microscopy. Four distinct damage morphologies were found: pits, flatbottom pits, scalds, and delaminates. The pits and flat bottom pits (<30{mu}m dia) were detected at lower fluences (as low as 5 J/cm{sup 2}). The pits seemed to result from ejection of nodular defects by causing local enhancement of the electric field. Scalds and delaminates could be observed at higher fluences (above 13 J/cm{sup 2}) and seemed to result from the formation of plasmas on the surface. These damage types often originated at pits and were less than 300 {mu}m diameter; their size increased almost linearly with fluence. Finally, effects of the damage on the beam (reflectivity degradation and phase modulations) were measured.

  6. The effect of particle-particle interaction forces on the flow properties of silica slurries

    SciTech Connect (OSTI)

    Harbottle, David; Fairweather, Michael; Biggs, Simon [Institute of Particle Science and Engineering, School of Process, Environmental and Materials Engineering, University of Leeds, UK, LS2 9JT (United Kingdom); Rhodes, Dominic [Nexia Solutions, Sellafield, Cumbria (United Kingdom)

    2007-07-01T23:59:59.000Z

    Preliminary work has been completed to investigate the effect of particle-particle interaction forces on the flow properties of silica slurries. Classically hydro-transport studies have focused on the flow of coarse granular material in Newtonian fluids. However, with current economical and environmental pressures, the need to increase solid loadings in pipe flow has lead to studies that examine non-Newtonian fluid dynamics. The flow characteristics of non-Newtonian slurries can be greatly influenced through controlling the solution chemistry. Here we present data on an 'ideal' slurry where the particle size and shape is controlled together with the solution chemistry. We have investigated the effect of adsorbed cations on the stability of a suspension, the packing nature of a sediment and the frictional forces to be overcome during re-slurrying. A significant change in the criteria assessed was observed as the electrolyte concentration was increased from 0.1 mM to 1 M. In relation to industrial processes, such delicate control of the slurry chemistry can greatly influence the optimum operating conditions of non-Newtonian pipe flows. (authors)

  7. Helium Adsorption in Silica Aerogel near the Liquid-Vapor Critical Point

    E-Print Network [OSTI]

    Tobias Herman; James Day; John Beamish

    2008-01-01T23:59:59.000Z

    We have investigated the adsorption and desorption of helium near its liquid-vapor critical point in silica aerogels with porosities between 95 % and 98%. We used a capacitive measurement technique which allowed us to probe the helium density inside the aerogel directly, even though the samples were surrounded by bulk helium. The aerogel’s very low thermal conductivity resulted in long equilibration times so we monitored the pressure and the helium density, both inside the aerogel and in the surrounding bulk, and waited at each point until all had stabilized. Our measurements were made at temperatures far from the critical point, where a well defined liquid-vapor interface exists, and at temperatures up to the bulk critical point. Hysteresis between adsorption and desorption isotherms persisted to temperatures close to the liquid-vapor critical point and there was no sign of an equilibrium liquid-vapor transition once the hysteresis disappeared. Many features of our isotherms can be described in terms of capillary condensation, although this picture becomes less applicable as the liquid-vapor critical point is approached and it is unclear how it can be applied to aerogels, whose tenuous structure includes a wide range of length scales. I.

  8. Corrugation of Phase-Separated Lipid Bilayers Supported by Nanoporous Silica Xerogel Surfaces

    SciTech Connect (OSTI)

    Goksu, E I; Nellis, B A; Lin, W; Satcher Jr., J H; Groves, J T; Risbud, S H; Longo, M L

    2008-10-30T23:59:59.000Z

    Lipid bilayers supported by substrates with nanometer-scale surface corrugations holds interest in understanding both nanoparticle-membrane interactions and the challenges of constructing models of cell membranes on surfaces with desirable properties, e.g. porosity. Here, we successfully form a two-phase (gel-fluid) lipid bilayer supported by nanoporous silica xerogel. Surface topology, diffusion, and lipid density in comparison to mica-supported lipid bilayers were characterized by AFM, FRAP, FCS, and quantitative fluorescence microscopy, respectively. We found that the two-phase lipid bilayer follows the xerogel surface contours. The corrugation imparted on the lipid bilayer results in a lipid density that is twice that on a flat mica surface. In direct agreement with the doubling of actual bilayer area in a projected area, we find that the lateral diffusion coefficient (D) of lipids on xerogel ({approx}1.7 {micro}m{sup 2}/s) is predictably lower than on mica ({approx}4.1 {micro}m{sup 2}/s) by both FRAP and FCS techniques. Furthermore, the gel-phase domains on xerogel compared to mica were larger and less numerous. Overall, our results suggest the presence of a relatively defect-free continuous two-phase bilayer that penetrates approximately midway into the first layer of {approx}50 nm xerogel beads.

  9. Sorption Phase of Supercritical CO2 in Silica Aerogel: Experiments and Mesoscale Computer Simulations

    SciTech Connect (OSTI)

    Rother, Gernot [ORNL; Vlcek, Lukas [ORNL; Gruszkiewicz, Miroslaw {Mirek} S [ORNL; Chialvo, Ariel A [ORNL; Anovitz, Lawrence {Larry} M [ORNL; Banuelos, Jose Leo [ORNL; Wallacher, Dirk [Helmholtz-Zentrum Berlin; Grimm, Nico [Helmholtz-Zentrum Berlin; Cole, David [Ohio State University

    2014-01-01T23:59:59.000Z

    Adsorption of supercritical CO2 in nanoporous silica aerogel was investigated by a combination of experiments and molecular-level computer modeling. High-pressure gravimetric and vibrating tube densimetry techniques were used to measure the mean pore fluid density and excess sorption at 35 C and 50 C and pressures of 0-200 bar. Densification of the pore fluid was observed at bulk fluid densities below 0.7 g/cm3. Far above the bulk fluid density, near-zero sorption or weak depletion effects were measured, while broad excess sorption maxima form in the vicinity of the bulk critical density region. The CO2 sorption properties are very similar for two aerogels with different bulk densities of 0.1 g/cm3 and 0.2 g/cm3, respectively. The spatial distribution of the confined supercritical fluid was analyzed in terms of sorption- and bulk-phase densities by means of the Adsorbed Phase Model (APM), which used data from gravimetric sorption and small-angle neutron scattering experiments. To gain more detailed insight into supercritical fluid sorption, large-scale lattice gas GCMC simulations were utilized and tuned to resemble the experimental excess sorption data. The computed three-dimensional pore fluid density distributions show that the observed maximum of the excess sorption near the critical density originates from large density fluctuations pinned to the pore walls. At this maximum, the size of these fluctuations is comparable to the prevailing pore sizes.

  10. FUNCTIONALIZED SILICA AEROGELS: ADVANCED MATERIALS TO CAPTURE AND IMMOBILIZE RADIOACTIVE IODINE

    SciTech Connect (OSTI)

    Matyas, Josef; Fryxell, Glen E.; Busche, Brad J.; Wallace, Krys; Fifield, Leonard S.

    2011-11-16T23:59:59.000Z

    To support the future expansion of nuclear energy, an effective method is needed to capture and safely store radiological iodine-129 released during reprocessing of spent nuclear fuel. Various materials have been investigated to capture and immobilize iodine. In most cases, however, the materials that are effective for capturing iodine cannot subsequently be sintered/densified to create a stable composite that could be a viable waste form. We have developed chemically modified, highly porous, silica aerogels that show sorption capacities higher than 440 mg of I2 per gram at 150 C. An iodine uptake test in dry air containing 4.2 ppm of iodine demonstrated no breakthrough after 3.5 h and indicated a decontamination factor in excess of 310. Preliminary densification tests showed that the I2-loaded aerogels retained more than 92 wt% of I2 after thermal sintering with pressure assistance at 1200 C for 30 min. These high capture and retention efficiencies for I2 can be further improved by optimizing the functionalization process and the chemistry as well as the sintering conditions.

  11. Helium adsorption in silica aerogel near the liquid-vapor critical point

    E-Print Network [OSTI]

    Tobias Herman; James Day; John Beamish

    2005-05-18T23:59:59.000Z

    We have investigated the adsorption and desorption of helium near its liquid-vapor critical point in silica aerogels with porosities between 95% and 98%. We used a capacitive measurement technique which allowed us to probe the helium density inside the aerogel directly, even though the samples were surrounded by bulk helium. The aerogel's very low thermal conductivity resulted in long equilibration times so we monitored the pressure and the helium density, both inside the aerogel and in the surrounding bulk, and waited at each point until all had stabilized. Our measurements were made at temperatures far from the critical point, where a well defined liquid-vapor interface exists, and at temperatures up to the bulk critical point. Hysteresis between adsorption and desorption isotherms persisted to temperatures close to the liquid-vapor critical point and there was no sign of an equilibrium liquid-vapor transition once the hysteresis disappeared. Many features of our isotherms can be described in terms of capillary condensation, although this picture becomes less applicable as the liquid-vapor critical point is approached and it is unclear how it can be applied to aerogels, whose tenuous structure includes a wide range of length scales.

  12. Compressed Silica Aerogels for the Study of Superfluid [superscript 3]He

    SciTech Connect (OSTI)

    Pollanen, J.; Choi, H.; Davis, J.P.; Blinstein, S.; Lippman, T.M.; Lurio, L.B.; Mulders, N.; Halperin, W.P. (NIU); (Delaware); (NWU)

    2007-03-02T23:59:59.000Z

    We have performed Small Angle X-ray Scattering (SAXS) on uniaxially strained aerogels and measured the strain-induced structural anisotropy. We use a model to connect our SAXS results to anisotropy of the {sup 3}He quasiparticle mean free path in aerogel. Measurements of the low temperature phase diagram of superfluid {sup 3}He in 98% aerogel indicate a stable B-phase and a metastable A-like phase. Vicente et al. proposed that the relative stability of these phases can be attributed to local anisotropic scattering of the 3He quasiparticles by the aerogel network. This network consists of silica strands with a diameter of {approx} 30 {angstrom} and average separation {zeta}{sub a} {approx} 300 {angstrom}. Vicente et al. also proposed using uniaxial strain of the aerogel to produce global anisotropy. We have performed SAXS on two uniaxially strained aerogels and found that strain introduces anisotropy on the {approx}100 {angstrom} length scale. We relate this to anisotropy of the quasiparticle mean free path, {lambda}.

  13. Comparisons between laser damage and optical electric field behaviors for hafnia/silica antireflection coatings

    SciTech Connect (OSTI)

    Bellum, John; Kletecka, Damon; Rambo, Patrick; Smith, Ian; Schwarz, Jens; Atherton, Briggs

    2011-03-20T23:59:59.000Z

    We compare designs and laser-induced damage thresholds (LIDTs) of hafnia/silica antireflection (AR) coatings for 1054 nm or dual 527 nm/1054 nm wavelengths and 0 deg. to 45 deg. angles of incidence (AOIs). For a 527 nm/1054 nm, 0 deg. AOI AR coating, LIDTs from three runs arbitrarily selected over three years are {approx}20 J/cm{sup 2} or higher at 1054 nm and <10 J/cm{sup 2} at 527 nm. Calculated optical electric field intensities within the coating show two intensity peaks for 527 nm but not for 1054 nm, correlating with the lower (higher) LIDTs at 527 nm (1054 nm). For 1054 nm AR coatings at 45 deg. and 32 deg. AOIs and S and P polarizations (Spol and Ppol), LIDTs are high for Spol (>35 J/cm{sup 2}) but not as high for Ppol (>30 J/cm{sup 2} at 32 deg. AOI; {approx}15 J/cm{sup 2} at 45 deg. AOI). Field intensities show that Ppol discontinuities at media interfaces correlate with the lower Ppol LIDTs at these AOIs. For Side 1 and Side 2 dual 527 nm/1054 nm AR coatings of a diagnostic beam splitter at 22.5 deg. AOI, Spol and Ppol LIDTs (>10 J/cm{sup 2} at 527 nm; >35 J/cm{sup 2} at 1054 nm) are consistent with Spol and Ppol intensity behaviors.

  14. Induction of apoptotic death and retardation of neuronal differentiation of human neural stem cells by sodium arsenite treatment

    SciTech Connect (OSTI)

    Ivanov, Vladimir N., E-mail: vni3@columbia.edu [Center for Radiological Research, Department of Radiation Oncology, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, NY 10032 (United States); Hei, Tom K. [Center for Radiological Research, Department of Radiation Oncology, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, NY 10032 (United States)

    2013-04-01T23:59:59.000Z

    Chronic arsenic toxicity is a global health problem that affects more than 100 million people worldwide. Long-term health effects of inorganic sodium arsenite in drinking water may result in skin, lung and liver cancers and in severe neurological abnormalities. We investigated in the present study whether sodium arsenite affects signaling pathways that control cell survival, proliferation and neuronal differentiation of human neural stem cells (NSC). We demonstrated that the critical signaling pathway, which was suppressed by sodium arsenite in NSC, was the protective PI3K–AKT pathway. Sodium arsenite (2–4 ?M) also caused down-regulation of Nanog, one of the key transcription factors that control pluripotency and self-renewal of stem cells. Mitochondrial damage and cytochrome-c release induced by sodium arsenite exposure was followed by initiation of the mitochondrial apoptotic pathway in NSC. Beside caspase-9 and caspase-3 inhibitors, suppression of JNK activity decreased levels of arsenite-induced apoptosis in NSC. Neuronal differentiation of NSC was substantially inhibited by sodium arsenite exposure. Overactivation of JNK1 and ERK1/2 and down-regulation of PI3K–AKT activity induced by sodium arsenite were critical factors that strongly affected neuronal differentiation. In conclusion, sodium arsenite exposure of human NSC induces the mitochondrial apoptotic pathway, which is substantially accelerated due to the simultaneous suppression of PI3K–AKT. Sodium arsenite also negatively affects neuronal differentiation of NSC through overactivation of MEK–ERK and suppression of PI3K–AKT. - Highlights: ? Arsenite induces the mitochondrial apoptotic pathway in human neural stem cells. ? Arsenite-induced apoptosis is strongly upregulated by suppression of PI3K–AKT. ? Arsenite-induced apoptosis is strongly down-regulated by inhibition of JNK–cJun. ? Arsenite negatively affects neuronal differentiation by inhibition of PI3K–AKT.

  15. Nano-Structured Mesoporous Silica Wires with Intra-Wire Lamellae via Evaporation-Induced Self-Assembly in Space-Confined Channels

    SciTech Connect (OSTI)

    Hu, Michael Z. [ORNL; Shi, Donglu [University of Cincinnati; Blom, Douglas Allen [ORNL

    2014-01-01T23:59:59.000Z

    Evaporation-induced self-assembly (EISA) of silica sol-gel ethanol-water solution mixtures with block-copolymer were studied inside uniform micro/nano channels. Nano-structured mesoporous silica wires, with various intra-wire self-assembly structures including lamellae, were prepared via EISA process but in space-confined channels with the diameter ranging from 50 nm to 200 nm. Membranes made of anodized aluminum oxide (AAO) and track-etched polycarbonate (EPC) were utilized as the arrays of space-confined channels (i.e., 50, 100, and 200-nm EPC and 200-nm AAO) for infiltration and drying of mixture solutions; these substrate membranes were submerged in mixture solutions consisting of a silica precursor, a structure-directing agent, ethanol, and water. After the substrate channels were filled with the solution under vacuum impregnation, the membrane was removed from the solution and dried in air. The silica precursor used was tetra-ethyl othosilicate (TEOS), and the structure-directing agent employed was triblock copolymer Pluronic-123 (P123). It was found that the formation of the mesoporous nanostructures in silica wires within uniform channels were significantly affected by the synthesis conditions including (1) pre-assemble TEOS aging time, (2) the evaporation rate during the vacuum impregnation, and (3) the air-dry temperature. The obtained intra-wire structures, including 2D-hexagonal rods and lamellae, were studied by scanning transmission electron microscopy (STEM). A steric hindrance effect seems to explain well the observed polymer-silica mesophase formation tailored by TEOS aging time. The evaporation effect, air-drying effect, and AAO-vs-EPC substrate effect on the mesoporous structure of the formed silica wires were also presented and discussed.

  16. Development of a neutronics calculation method for designing commercial type Japanese sodium-cooled fast reactor

    SciTech Connect (OSTI)

    Takeda, T.; Shimazu, Y.; Hibi, K.; Fujimura, K. [Research Inst. of Nuclear Engineering, Univ. of Fukui, 1cho-me 2gaiku 4, Kanawa-cho, Tsuruga-shi, Fukui 914-0055 (Japan)

    2012-07-01T23:59:59.000Z

    Under the R and D project to improve the modeling accuracy for the design of fast breeder reactors the authors are developing a neutronics calculation method for designing a large commercial type sodium- cooled fast reactor. The calculation method is established by taking into account the special features of the reactor such as the use of annular fuel pellet, inner duct tube in large fuel assemblies, large core. The Verification and Validation, and Uncertainty Qualification (V and V and UQ) of the calculation method is being performed by using measured data from the prototype FBR Monju. The results of this project will be used in the design and analysis of the commercial type demonstration FBR, known as the Japanese Sodium fast Reactor (JSFR). (authors)

  17. Sodium/sulfur battery engineering for stationary energy storage. Final report

    SciTech Connect (OSTI)

    Koenig, A.; Rasmussen, J. [Silent Power, Inc., Salt Lake City, UT (United States)

    1996-04-01T23:59:59.000Z

    The use of modular systems to distribute power using batteries to store off-peak energy and a state of the art power inverter is envisioned to offer important national benefits. A 4-year, cost- shared contract was performed to design and develop a modular, 300kVA/300-kWh system for utility and customer applications. Called Nas-P{sub AC}, this system uses advanced sodium/sulfur batteries and requires only about 20% of the space of a lead-acid-based system with a smaller energy content. Ten, 300-VDC, 40-kWh sodium/sulfur battery packs are accommodated behind a power conversion system envelope with integrated digital control. The resulting design facilities transportation, site selection, and deployment because the system is quiet and non-polluting, and can be located in proximity to the load. This report contains a detailed description of the design and supporting hardware development performed under this contract.

  18. Idaho Nuclear Technology and Engineering Center (INTEC) Sodium Bearing Waste - Waste Incidental to Reprocessing Determination

    SciTech Connect (OSTI)

    Jacobson, Victor Levon

    2002-08-01T23:59:59.000Z

    U.S. Department of Energy Manual 435.1-1, Radioactive Waste Management, Section I.1.C, requires that all radioactive waste subject to Department of Energy Order 435.1 be managed as high-level radioactive waste, transuranic waste, or low-level radioactive waste. Determining the radiological classification of the sodium-bearing waste currently in the Idaho Nuclear Technology and Engineering Center Tank Farm Facility inventory is important to its proper treatment and disposition. This report presents the technical basis for making the determination that the sodium-bearing waste is waste incidental to spent fuel reprocessing and should be managed as mixed transuranic waste. This report focuses on the radiological characteristics of the sodiumbearing waste. The report does not address characterization of the nonradiological, hazardous constituents of the waste in accordance with Resource Conservation and Recovery Act requirements.

  19. Two dimensional, two fluid model for sodium boiling in LMFBR fuel assemblies

    SciTech Connect (OSTI)

    Granziera, M.R.; Kazimi, M.S.

    1980-05-01T23:59:59.000Z

    A two dimensional numerical model for the simulation of sodium boiling transient was developed using the two fluid set of conservation equations. A semiimplicit numerical differencing scheme capable of handling the problems associated with the ill-posedness implied by the complex characteristic roots of the two fluid problems was used, which took advantage of the dumping effect of the exchange terms. Of particular interest in the development of the model was the identification of the numerical problems caused by the strong disparity between the axial and radial dimensions of fuel assemblies. A solution to this problem was found which uses the particular geometry of fuel assemblies to accelerate the convergence of the iterative technique used in the model. Three sodium boiling experiments were simulated with the model, with good agreement between the experimental results and the model predictions.

  20. Boiling behavior of sodium-potassium alloy in a bench-scale solar receiver

    SciTech Connect (OSTI)

    Moreno, J.B.; Andraka, C.E.; Moss, T.A.

    1992-01-01T23:59:59.000Z

    During 1989-90, a 75-kW{sub t} sodium reflux pool-boiler solar receiver was successfully demonstrated at Sandia National Laboratories. Significant features of this receiver include (1) boiling sodium as the heat transfer medium and (2) electric-discharge-machined (EDM) cavities as artificial nucleation sites to stabilize boiling. Since this first demonstration, design of a second-generation pool-boiler receiver that will bring the concept closer to commercialization has begun. For long life, the new receiver uses Haynes Alloy 230. For increased safety factors against film boiling and flooding, it has a refined shape and somewhat larger dimensions. To eliminate the need for trace heating, the receiver will boil the sodium-potassium alloy NaK-78 instead of sodium. To reduce manufacturing costs, it will use one of a number of alternatives to EDM cavities for stabilization of boiling. To control incipient-boiling superheats, especially during hot restarts, it will contain a small amount of inert gas. Before the new receiver design could be finalized, bench-scale tests of some of the proposed changes were necessary. A series of bench-scale pool boilers were built from Haynes Alloy 230 and filled with NaK-78. Various boiling-stabilizer candidates were incorporated into them, including laser-drilled cavities and a number of different sintered-powder-metal coatings. These bench-scale pool boilers have been operated at temperatures up to 750{degree}C, heated by quartz lamps with incident radiant fluxes up to 95 W/cm{sup 2}. The effects of various orientations and added gases have been studied. results of these studies are presented. 15 refs.