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Sample records for borosilicates

  1. The borosilicate glass for 'PAMELA'

    International Nuclear Information System (INIS)

    Schiewer, E.

    1986-01-01

    The low enriched waste concentrate (LEWC) stored at Mol, Belgium, will be solidified in the vitrification plant 'PAMELA'. An alkali-borosilicate glass was developed by the Hahn-Meitner-Institut, Berlin, which dissolves (11 +- 3)wt% waste oxides while providing sufficient flexibility for changes in the process parameters. The development of the glass labelled SM513LW11 is described. Important properties of the glass melt (viscosity, resistivity, formation of yellow phase) and of the glass (corrosion in aqueous solutions, crystallization) are reported. The corrosion data of this glass are similar to those of other HLW-glasses. Less than five wt% of crystalline material are produced upon cooling of large glass blocks. Crystallization does not affect the chemical durability. (Auth.)

  2. Safety assessment of borosilicate glasses as used in cosmetics.

    Science.gov (United States)

    Becker, Lillian C; Bergfeld, Wilma F; Belsito, Donald V; Hill, Ronald A; Klaassen, Curtis D; Liebler, Daniel C; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Andersen, F Alan

    2013-01-01

    The Cosmetic Ingredient Review Expert Panel (Panel) reviewed the safety of calcium sodium borosilicate, calcium aluminum borosilicate, calcium titanium borosilicate, silver borosilicate, and zinc borosilicate as used in cosmetics. These borosilicate glasses function mostly as bulking agents. Available animal and human data were considered along with data from a previous safety assessment of magnesium silicates. The similar structure, properties, functions, and uses of these ingredients enabled grouping them and using the available toxicological data to assess the safety of the entire group. Data submitted on calcium borosilicate, which is not a cosmetic ingredient, are also included as additional support for the safety of borosilicate glass ingredients. The Panel concluded that borosilicate glasses are safe as cosmetic ingredients in the practices of use and concentration as given in this safety assessment.

  3. Topological Principles of Borosilicate Glass Chemistry

    DEFF Research Database (Denmark)

    Smedskjær, Morten Mattrup; Mauro, J. C.; Youngman, R. E.

    2011-01-01

    and laboratory glassware to high-tech applications such as liquid crystal displays. In this paper, we investigate the topological principles of borosilicate glass chemistry covering the extremes from pure borate to pure silicate end members. Based on NMR measurements, we present a two-state statistical...

  4. Titanium impregnated borosilicate zeolites for epoxidation catalysis

    Czech Academy of Sciences Publication Activity Database

    Přech, Jan; Vitvarová, Dana; Lupínková, Lenka; Kubů, Martin; Čejka, Jiří

    2015-01-01

    Roč. 212, AUG 2015 (2015), s. 28-34 ISSN 1387-1811 R&D Projects: GA ČR GAP106/11/0819 Institutional support: RVO:61388955 Keywords : borosilicate * titanium impregnation * epoxidation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.349, year: 2015

  5. Borosilicate glass for gamma irradiation fields

    Science.gov (United States)

    Baydogan, N.; Tugrul, A. B.

    2012-11-01

    Four different types of silicate glass specimens were irradiated with gamma radiation using a Co-60 radioisotope. Glass specimens, with four different chemical compositions, were exposed to neutron and mixed neutron/gamma doses in the central thimble and tangential beam tube of the nuclear research reactor. Optical variations were determined in accordance with standardisation concept. Changes in the direct solar absorbance (αe) of borosilicate glass were examined using the increase in gamma absorbed dose, and results were compared with the changes in the direct solar absorbance of the three different type silicate glass specimens. Solar absorption decreased due to decrease of penetration with absorbed dose. αe of borosilicate increased considerably when compared with other glass types. Changes in optical density were evaluated as an approach to create dose estimation. Mixed/thermal neutron irradiation on glass caused to increse αe.

  6. Investigation on neptunium in a borosilicate glass

    International Nuclear Information System (INIS)

    Poirot, I.

    1988-03-01

    The oxidization state and coordination of neptunium, introduced as dopant in borosilicate glasses were studied through optical, Mossbauer spectroscopies and magnetic measurements. The neptunium oxide, introduced previously as NpO 2 is reduced during the melting process of the glass. This leads to an equilibrium in which the ratio of Np 4+ to Np 3+ valences depends on experimental conditions. Spectroscopic analysises conduct to postulate the presence of different sites for each of the oxydation states of neptunium [fr

  7. Thermodynamic properties of alkali borosilicate gasses and metaborates

    International Nuclear Information System (INIS)

    Asano, Mitsuru

    1992-01-01

    Borosilicate glasses are the proposed solidifying material for storing high level radioactive wastes in deep underground strata. Those have low melting point, and can contain relatively large amount of high level radioactive wastes. When borosilicate glasses are used for this purpose, they must be sufficiently stable and highly reliable in the vitrification process, engineered storage and the disposal in deep underground strata. The main vaporizing components from borosilicate glasses are alkali elements and boron. In this report, as for the vaporizing behavior of alkali borosilicate glasses, the research on thermodynamic standpoint carried out by the authors is explained, and the thermodynamic properties of alkali metaborates of monomer and dimer which are the main evaporation gases are reported. The evaporation and the activity of alkali borosilicate glasses, the thermodynamic properties of alkali borosilicate glasses, gaseous alkali metaborates and alkali metaborate system solid solution and so on are described. (K.I.)

  8. Topological Principles of Borosilicate Glass Chemistry - An Invited Talk

    DEFF Research Database (Denmark)

    Mauro, J.C.; Smedskjær, Morten Mattrup; Youngman, R. E.

    Borosilicate glasses display a rich complexity of chemical behavior depending on the details of their composition and thermal history. We investigate the topological principles of borosilicate glass chemistry covering the extremes from pure borate to pure silicate end members. Based on NMR...... topological representation of alkali-alkaline earth-borosilicate glasses that enables the accurate prediction of properties such as glass transition temperature, liquid fragility, hardness, and configurational heat capacity. The implications of the glass topology are discussed in terms of both the temperature...

  9. 57Fe Moessbauer effect in borosilicate glasses

    International Nuclear Information System (INIS)

    Music, S.

    1989-01-01

    The present study was carried out to elucidate the valence state of iron and its co-ordination in borosilicate glasses, which are being investigated as possible solidification matrices for the immobilization of a simulated nuclear waste. 57 Fe Mossbauer spectroscopy was used as the experimental technique. The chemical compositions of glass samples and the experimental conditions for the preparation of these samples are given. Iron in the form of haematite (α-Fe 2 O 3 ) was used as doping material. Details of the experimental procedure have previously been described. Isomer shifts are calculated relative to α-iron. The results indicate a strong dependence of the valency of the iron and its coordination on the chemical composition of the glass and the Fe 2 O 3 content. The method of preparing the glasses also influences the state of the iron in oxide glasses. (Author)

  10. The structure of leached sodium borosilicate glass

    International Nuclear Information System (INIS)

    Bunker, B.C.; Tallant, D.R.; Headley, T.J.; Turner, G.L.; Kirkpatrick, R.J.

    1988-01-01

    Raman spectroscopy, solid state 29 Si, 11 B, 17 O, and 23 Na nuclear magnetic resonance spectroscopy, and transmission electron microscopy have been used to investigate how the structures of sodium borosilicate glasses change during leaching in water at pH 1, 9, and 12. Results show that the random network structure present prior to leaching is transformed into a network of small condensed ring structures and/or colloidal silica particles. The restructuring of leached glass can be rationalised on the basis of simple hydrolysis (depolymerisation) and condensation (repolymerisation) reactions involving Si-O-Si and Si-O-B bonds. The structural changes that occur during leaching influence the properties of the leached layer, including leaching kinetics, crazing and spalling, and slow crack growth. (author)

  11. Plutonium alteration phases from lanthanide borosilicate glass

    International Nuclear Information System (INIS)

    Fortner, J.A.; Mertz, C.J.; Chamberlain, D.C.; Bates, J.K.

    1997-01-01

    A prototype lanthanide borosilicate (LaBS) glass containing 10 mass % plutonium was reacted with water vapor at 200 C for periods of 14 to 56 days. These tests, while not designed to replicate specific conditions that may be found in a potential geologic repository (e.g., Yucca Mountain), have been shown to accelerate alteration phase formation. The surfaces of the glass samples, along with alteration phases, were examined with a transmission electron microscope (TEM). Tests of 14 days produced macroscopic (∼ 20 microm) crystallites of a plutonium-lanthanide silicate. An extensive alteration layer was found on the glass surface containing amorphous aluminosilicate layered with bands of a cryptocrystalline plutonium silicate. After 56 days of testing, additional alteration phases were formed, including a strontium lanthanide oxide phase. One of the options for disposal of surplus plutonium, particularly for impure residues that may be unfit for production of MOX fuel, is vitrification followed by geologic disposal. Since geologic disposal requires a passive system to isolate the radiotoxic elements from the biosphere, it is important to understand the possible corrosion mechanisms of the waste form

  12. WAXS investigation of lanthanide borosilicate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Bouty, O. [DEN/DTEC/SEPE, CEA Marcoule, BP 17171, Bagnols-sur-Ceze cedex, 30207 (France); Delaye, J.M.; DeBonfils, J.; Peuget, S. [DEN/DTCD/SECM, CEA Marcoule, BP 17171, Bagnols-sur-Ceze cedex, 30207 (France)

    2008-07-01

    Structural characterization of nuclear glasses requires the combination of several experimental and simulation techniques. Experimental ones probe the electronic environment at short distances (EXAFS, NMR) or at medium range distances (WAXS, AWAXS) or the nuclear environment (neutron scattering). We have built a new competence in X Ray Wide Angle Scattering (WAXS) by mounting two based-lab diffractometers with Mo X ray tubes, one of them being located in a shielded glove box, and by writing a new software to easily extract structure factors and radial distribution functions from the experiment. We present here a preliminary study of a simplified borosilicate glass doped with Eu (europium), which is a fission product, and which is often used as a stimulant of trivalent actinides. The WAXS technique has been successfully applied, the structure factor being in good agreement with the one obtained by molecular dynamics simulation. Thus, knowledge of the Eu local environment has been deduced and results compared with data from EXAFS and NMR analysis. (authors)

  13. Thermogravimetry analysis on fused borosilicate syntactic foams

    Science.gov (United States)

    Salleh, Zulzamri; Islam, Md Mainul; Epaarachchi, Jayantha Ananda

    2017-12-01

    Fused borosilicate/vinyl ester syntactic foams mostly used for thermal stability in many applications are considered to be characterised for their properties in higher temperature condition. Therefore, higher temperature characteristics need to be explored with respect to physical parameters such as porosity and void content. The filler, also known as glass microballoons, was incorporated in vinyl ester resin matrix in 2wt%, 4wt%, 6wt.%, 8wt.% and 10wt.%. These composites are characterised and degraded to examine the onset temperature, Tonset, peak temperature, Tpeak and end temperature, Tend using thermogravimetric analysis (TGA) method. The results for Tonset showed an increment while Tend and Tpeak showed decrement when glass microballoons were added in syntactic foams. Based on TGA data, they exhibited excellent thermal stability, showing 5% weight loss at 380-450 °C. Glass transition temperature (Tg) decreased when more glass microballoons were added, and also related to the effect on the physical properties of syntactic foams. Therefore, understanding of the relationship between thermal properties of syntactic foams and their physical properties such as porosity and void content will help in developing syntactic foams to optimise their thermal characteristics, which will be beneficial for engineering applications.

  14. TiO3 borosilicate glass–ceramics

    Indian Academy of Sciences (India)

    phase of the glass–ceramic sample with x ≤ 0·5 was found to have cubic structure similar to SrTiO3 ceramic. Scanning electron microscopy has been carried out to see the surface morphology of the crystallites dispersed in the glassy matrix. Keywords. (PbSr)TiO3 borosilicate glasses; infrared spectroscopy; DTA; XRD and ...

  15. Utilization of borosilicate glass for transuranic waste immobilization

    International Nuclear Information System (INIS)

    Ledford, J.A.; Williams, P.M.

    1979-01-01

    Incinerated transuranic waste and other low-level residues have been successfully vitrified by mixing with boric acid and sodium carbonate and heating to 1050 0 C in a bench-scale continuous melter. The resulting borosilicate glass demonstrates excellent mechanical durability and chemical stability

  16. IR study of Pb–Sr titanate borosilicate glasses

    Indian Academy of Sciences (India)

    Administrator

    IR study of Pb–Sr titanate borosilicate glasses. C R GAUTAM*, DEVENDRA KUMAR. † and OM PARKASH. †. Department of Physics, University of Lucknow, Lucknow 226 007, India. †. Department of Ceramic Engineering, Institute of Technology, Banaras Hindu University, Varanasi 221 005, India. MS received 3 January ...

  17. Chemical durability of zinc borosilicate nuclear waste glass

    International Nuclear Information System (INIS)

    Westsik, J.H. Jr.; Mendel, J.E.

    1977-03-01

    Chemical durability is of primary concern when evaluating the safety of waste glass. For this reason, testing the leachability of waste glasses is a fundamental part of their development and characterization. The leachability is also very much a function of glass composition as previously discussed. This discussion is limited to a representative waste glass composition, a high-zinc borosilicate formulation which has been studied in detail by Battelle Pacific Northwest Laboratories

  18. Assessment of Savannah River borosilicate glass in the repository environment

    International Nuclear Information System (INIS)

    Plodinec, M.J.; Wicks, G.G.; Bibler, N.E.

    1982-04-01

    Since 1973, borosilicate glass has been studied as a matrix for the immobilization of high-level radioactive waste generated at the Savannah River Plant (SRP). In 1977, efforts began to develop and test the large-scale equipment necessary to convert the alkaline waste slurries at SRP into a durable borosilicate glass. A process has now been developed for the proposed Defense Waste Processing Facility (DWPF) which will annually produce approximately 500 canisters of SRP waste glass which will be stored on an interim basis on the Savannah River site. Current national policy calls for the permanent disposal of high-level waste in deep geologic repositories. In the repository environment, SRP waste glass will eventually be exposed to such stresses as lithostatic or hydrostatic pressures, radiation fields, and self-heating due to radioactive decay. In addition, producing and handling each canister of glass will also expose the glass to thermal and mechanical stresses. An important objective of the extensive glass characterization and testing programs of the Savannah River Laboratory (SRL) has been to determine how these stresses affect the performance of SRP waste glass. The results of these programs indicate that: these stresses will not significantly affect the performance of borosilicate glass containing SRP waste; and SRP waste glass will effectively immobilize hazardous radionuclides in the repository environment

  19. Sulphate Incorporation in Borosilicate Glasses and Melts: a Kinetic Approach

    Energy Technology Data Exchange (ETDEWEB)

    Lenoir, M. [CEA, DEN, Laboratoire d' etude et de Developpement de Matrices de Conditionnement, Centre de Marcoule, 30207 Bagnols-sur-Ceze (France); Physique des Mineraux et Magmas, UMR 7047, CNRS- Institut de Physique du Globe de Paris, 7 place Jussieu, 75252 Paris 05 (France); Grandjean, A. [Institut de Chimie Separative de Marcoule, UMR 5257, Laboratoire des Nanomateriaux Autoreparants, Marcoule, 30207 Bagnols-sur-Ceze (France); Dussossoy, J.L. [CEA, DEN, Laboratoire d' etude et de Developpement de Matrices de Conditionnement, Centre de Marcoule, 30207 Bagnols-sur-Ceze (France); Neuville, D.R. [Physique des Mineraux et Magmas, UMR 7047, CNRS- Institut de Physique du Globe de Paris, 7 place Jussieu, 75252 Paris 05 (France)

    2008-07-01

    The kinetics of sulphate departure in a sodium borosilicate melt were studied using in situ Raman spectroscopy. This technique allows the quantification of the amount of sulphate dissolved in a borosilicate glass as a function of heating time by comparison with measurements obtained by microprobe wavelength dispersive spectrometry. To quantify the sulphate content obtained with Raman spectroscopy, the integrated intensity of the sulphate band at 990 cm{sup -1} was scaled to the sum of the integrated bands between 800 and 1200 cm{sup -1}, bands that are assigned to Qn silica units on the basis of previous literature. Calibration curves were then determined for two different samples. An evaluation of the kinetics of departure of sulphate could thus be made as a function of the viscosity of the borosilicate glass, showing that the kinetics were controlled by the diffusion of sulphate and its volatilization from the melt. This experimental method allows in situ measurements of sulphate content at high temperature which cannot be obtained by any other simple technique. (authors)

  20. Radiation response of cubic mesoporous silicate and borosilicate thin films

    Science.gov (United States)

    Manzini, Ayelén; Alurralde, Martín; Luca, Vittorio

    2018-01-01

    The radiation response has been studied of cubic mesoporous silicate and borosilicate thin films having different boron contents prepared using the block copolymer template Brij 58 and the dip coating technique. The degree of pore ordering of the films was analysed using low-angle X-ray diffraction and film thickness measured by X-ray reflectivity. For films calcined at 350 °C, the incorporation of boron resulted in a reproducible oscillatory variation in the d-spacing and intensity of the primary reflection as a function of boron content. A clear peak was observed in the d-spacing at 5-10 mol% boron incorporation. For borosilicate films of a given composition an overall suppression of d-spacing was observed as a function of aging time relative to films that did not contain boron. This was ascribed to a slow condensation process. The films were irradiated in pile with neutrons and with iodine ions at energies of 180 keV and 70 MeV. Neutron irradiation of the silicate thin films for periods up to 30 days and aged for 400 days resulted in little reduction in either d-spacing or intensity of the primary low-angle X-ray reflection indicating that the films retained their mesopore ordering. In contrast borosilicate films for which the B (n, α) reaction was expected to result in enhanced displacement damage showed much larger variations in X-ray parameters. For these films short irradiation times resulted in a reduction of the d-spacing and intensity of the primary reflections considerably beyond that observed through aging. It is concluded that prolonged neutron irradiation and internal α irradiation have only a small, although measurable, impact on mesoporous borosilicate thin films increasing the degree of condensation and increasing unit cell contraction. When these borosilicate films were irradiated with iodine ions, more profound changes occurred. The pore ordering of the films was significantly degraded when low energy ions were used. In some cases the degree

  1. Low Velocity Sphere Impact of a Borosilicate Glass

    Energy Technology Data Exchange (ETDEWEB)

    Morrissey, Timothy G [ORNL; Ferber, Mattison K [ORNL; Wereszczak, Andrew A [ORNL; Fox, Ethan E [ORNL

    2012-05-01

    This report summarizes US Army TARDEC sponsored work at Oak Ridge National Laboratory (ORNL) involving low velocity (< 30 m/s or < 65 mph) ball impact testing of Borofloat borosilicate glass, and is a follow-up to a similar study completed by the authors on Starphire soda-lime silicate glass last year. The response of the borosilicate glass to impact testing at different angles was also studied. The Borofloat glass was supplied by the US Army Research Laboratory and its tin-side was impacted or indented. The intent was to better understand low velocity impact response in the Borofloat. Seven sphere materials were used whose densities bracket that of rock: borosilicate glass, soda-lime silicate glass, silicon nitride, aluminum oxide, zirconium oxide, carbon steel, and a chrome steel. A gas gun or a ball-drop test setup was used to produce controlled velocity delivery of the spheres against the glass tile targets. Minimum impact velocities to initiate fracture in the Borofloat were measured and interpreted in context to the kinetic energy of impact and the elastic property mismatch between the seven sphere-Borofloat-target combinations. The primary observations from this low velocity (< 30 m/s or < 65 mph) testing were: (1) BS glass responded similarly to soda-lime silicate glass when spherically indented but quite differently under sphere impact conditions; (2) Frictional effects contributed to fracture initiation in BS glass when it spherically indented. This effect was also observed with soda-lime silicate glass; (3) The force necessary to initiate fracture in BS glass under spherical impact decreases with increasing elastic modulus of the sphere material. This trend is opposite to what was observed with soda-lime silicate glass. Friction cannot explain this trend and the authors do not have a legitimate explanation for it yet; (4) The force necessary to initiate contact-induced fracture is higher under dynamic conditions than under quasi-static conditions. That

  2. INTERFACE DEFEAT OF LONG RODS IMPACTING BOROSILICATE GLASS EXPERIMENTAL RESULTS

    Science.gov (United States)

    2009-02-01

    impact velocity vc consumption velocity vF failure front velocity tCu time to penetrate the Cu buffer or cover plate tdwell time interval that rod...dwelled on glass surface = tpen – tCu tpen time to begin penetration after impact vhydro hydrodynamic penetration velocity, Eqn. (4) ρt target...impact velocity for bare borosilicate glass. Table 4. Further Analyses of Experimental Data oc dCu h vp tCu tpen tdwell Exp. [mm] [mm] [mm] [m/s

  3. Synthesis and characterization of acidic mesoporous borosilicate thin films.

    Science.gov (United States)

    Xiu, Tongping; Liu, Qian; Wang, Jiacheng

    2009-02-01

    Work on the synthesis and characterization of acidic wormhole-like ordered mesoporous borosilicate thin films (MBSTFs) on silicon wafers is described in this paper. The MBSTFs coated by the dip-coating method were prepared through an evaporation-induced self-assembly (EISA) process using nonionic block copolymers as structure-directing agents. Fourier transform infrared (FT-IR) spectroscopy confirmed the formation of borosiloxane bonds (Si-O-B). High-resolution transmission electron microscopy (HRTEM) and N2 sorption evidenced a wormhole-like mesoporous structure in the MBSTFs obtained. Scanning electron microscopy (SEM) images of the cross sections and surfaces of the samples showed that MBSTFs on silicon wafers were continuous, homogeneous and did not crack. The acidic properties of the MBSTFs were characterized by FT-IR spectra of chemisorbed pyridine. The MBSTFs thus prepared may find their future applications in many fields including chemical sensors, catalysis, optical coating, molecule separation, etc.

  4. Crystallization characteristics of lithium calcium gallium aluminium borosilicate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Darwish, H.; Salama, S.N.; Salman, S.M. [National Research Centre, Cairo (Egypt). Glass Research Dept.

    2002-07-01

    The crystallization processes of lithium calcium gallium borosilicate glass containing Al{sub 2}O{sub 3} have been followed by X-ray diffractometry (XRD), differential thermal analysis (DTA) and scanning electron microscope (SEM). Lithium gallium silicate - LiGaSiO{sub 4} phase was formed as a major constituent during the crystallization of the base glass. Solid solutions of lithium aluminosilicate and lithium aluminium gallium silicate - LiAl{sub 0.5}Ga{sub 0.5}SiO{sub 4} phases were mostly formed as a function of Al{sub 2}O{sub 3}/Ga{sub 2}O{sub 3} ratios in the glasses. Varieties of lithium borate phases including Li{sub 2}B{sub 4}O{sub 7}, {alpha}-Li{sub 4}B{sub 2}O{sub 5}, Li{sub 3}BO{sub 3}, {beta}-LiBO{sub 2} and LiB{sub 3}O{sub 5} phases were detected together with lithium metasilicate and lithium disilicate. Different calcium bearing phases including wollastonite-CaSiO{sub 3}, calcium borosilicate -Ca{sub 2}B{sub 2}SiO{sub 7}, larnite -Ca{sub 2}SiO{sub 4}, rankinite -Ca{sub 3}Si{sub 2}O{sub 7}, and calcium borate -CaB{sub 2}O{sub 4} were mainly detected as a function of heat-treatment in the CaO-containing samples. The role played by the glass oxide constituents in determining the crystallization characteristics and the nature of the crystal phases formed in the glasses are discussed. (orig.)

  5. sup 1 sup 1 B nutation NMR study of powdered borosilicates

    CERN Document Server

    Woo, A J; Han, D Y

    1998-01-01

    In this work, we applied the 1D sup 1 sup 1 B nutation NMR method for the analysis of the local structural environments in powdered borosilicates (SiO sub 2 -B sub 2 O sub 3). Spin dynamics during a rf irradiation for spin I=3/2 was analytically calculated with a density matrix formalism. Spectral simulation programs were written in MATLAB on a PC. Two borosilicates prepared by the sol-gel process at different stabilization temperature were used for the 1D sup 1 sup 1 B nutation NMR experiment. The sup 1 sup 1 B NMR parameters, quadrupole coupling constants (e sup 2 qQ/h) and asymmetry parameters (eta), for each borosilicate were extracted from the nonlinear least-squares fitting. The effects of heat treatments on the local structures of boron sites in borosilicates were discussed.

  6. A novel low cost polyvinyl alcohol-Nafion-borosilicate membrane separator for microbial fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, B.R. [Department of Civil Engineering, Indian Institute of Technology, Kharagpur, 721302 (India); Noori, Md.T. [Department of Agriculture and Food Engineering, Indian Institute of Technology, Kharagpur, 721302 (India); Ghangrekar, M.M., E-mail: ghangrekar@civil.iitkgp.ernet.in [Department of Civil Engineering, Indian Institute of Technology, Kharagpur, 721302 (India)

    2016-10-01

    Composite membranes were developed from PVA-borosilicate (MP) and PVA-Nafion-borosilicate (MPN) for application in microbial fuel cells (MFCs). The membranes were characterized in terms of water uptake, PBS uptake, oxygen diffusion and proton conductivity. Proton conductivity for MPN (0.07 Scm{sup −1}) was found to be higher as compared to that of MP (0.03 Scm{sup −1}). Oxygen diffusion coefficient for MPN was 1.47 fold lower than that for MP. As a result, MFC with PVA-Nafion-borosilicate membrane exhibited maximum power density of 6.8 Wm{sup −3}, which was 151% higher than the power produced by MFC having PVA-borosilicate membrane and it was comparable with MFC using Nafion 117 (7.1 Wm{sup −3}) membrane separator. This study demonstrates that borosilicate glass membrane incorporated with PVA-Nafion matrix can be a suitable alternative to costly polymeric membrane to increase power output of MFC. Using such membranes MFC can be fabricated at around 11 fold reduced cost as compared to Nafion 117. - Highlights: • Novel membranes using PVA and borosilicate composite were fabricated. • Proton diffusion for MPN was comparable with Nafion117. • MFC-PN produced power density comparable to MFC with Nafion 117 membrane. • MPN was fabricated at almost 11 times reduced cost than Nafion 117 membranes.

  7. Alpha self irradiation effects in nuclear borosilicate glass

    International Nuclear Information System (INIS)

    Peuget, S.; Roudil, D.; Deschanels, X.; Jegou, C.; Broudic, V.; Bart, J.M.

    2004-01-01

    The properties of actinide glasses are studied in the context of high-level waste management programs. Reprocessing high burnup fuels in particular will increase the minor actinide content in the glass package, resulting in higher cumulative alpha decay doses in the glass, and raising the question of the glass matrix behavior and especially its containment properties. The effect of alpha self-irradiation on the glass behavior is evaluated by doping the glass with a short-lived actinide ( 244 Cm) to reach in several years the alpha dose received by the future glass packages over several thousand years. 'R7T7' borosilicate glasses were doped with 3 different curium contents (0.04, 0.4 and 1.2 wt% 244 CmO 2 ). The density and mechanical properties of the curium-doped glasses were characterized up to 2. 10 18 α/g, revealing only a slight evolution of the macroscopic behavior of R7T7 glass in this range. The leaching behavior of curium-doped glass was also studied by Soxhlet tests. The results do not show any significant evolution of the initial alteration rate with the alpha dose. (authors)

  8. Composition-Structure-Property Relations of Compressed Borosilicate Glasses

    Science.gov (United States)

    Svenson, Mouritz N.; Bechgaard, Tobias K.; Fuglsang, Søren D.; Pedersen, Rune H.; Tjell, Anders Ø.; Østergaard, Martin B.; Youngman, Randall E.; Mauro, John C.; Rzoska, Sylwester J.; Bockowski, Michal; Smedskjaer, Morten M.

    2014-08-01

    Hot isostatic compression is an interesting method for modifying the structure and properties of bulk inorganic glasses. However, the structural and topological origins of the pressure-induced changes in macroscopic properties are not yet well understood. In this study, we report on the pressure and composition dependences of density and micromechanical properties (hardness, crack resistance, and brittleness) of five soda-lime borosilicate glasses with constant modifier content, covering the extremes from Na-Ca borate to Na-Ca silicate end members. Compression experiments are performed at pressures ≤1.0 GPa at the glass transition temperature in order to allow processing of large samples with relevance for industrial applications. In line with previous reports, we find an increasing fraction of tetrahedral boron, density, and hardness but a decreasing crack resistance and brittleness upon isostatic compression. Interestingly, a strong linear correlation between plastic (irreversible) compressibility and initial trigonal boron content is demonstrated, as the trigonal boron units are the ones most disposed for structural and topological rearrangements upon network compaction. A linear correlation is also found between plastic compressibility and the relative change in hardness with pressure, which could indicate that the overall network densification is responsible for the increase in hardness. Finally, we find that the micromechanical properties exhibit significantly different composition dependences before and after pressurization. The findings have important implications for tailoring microscopic and macroscopic structures of glassy materials and thus their properties through the hot isostatic compression method.

  9. Structural origin of hardness decrease in irradiated sodium borosilicate glass

    Science.gov (United States)

    Yuan, Wei; Peng, Haibo; Sun, Mengli; Du, Xin; Lv, Peng; Zhao, Yan; Liu, Fengfei; Zhang, Bingtao; Zhang, Xiaoyang; Chen, Liang; Wang, Tieshan

    2017-12-01

    Mechanical properties such as hardness and modulus of sodium borosilicate (NBS) glasses in irradiation conditions were studied extensively in recent years. With irradiation of heavy ions, a trend that the hardness of NBS glasses decreased and then stabilized with increase of dose has been reported. Variations in network structures were suggested for the decrease of hardness after irradiation. However, details of these variations in a network of glass are not clear yet. In this paper, molecular dynamics was applied to simulate the network variations in a type of NBS glass and the changes in hardness after xenon irradiation. The simulation results indicated that hardness variation decreased with fluence in an exponential law, which was consistent with experimental results. The origin of hardness decrease after irradiation might be attributed to the break of Biv-O links that could be derived from the (1) decrease of average coordinate number of boron, (2) decrease of Si-O-Biv bonds, and (3) increase of non-bridging oxygen.

  10. Determination of the free enthalpies of formation of borosilicate glasses

    International Nuclear Information System (INIS)

    Linard, Y.

    2000-01-01

    This work contributes to the study of the thermochemical properties of nuclear waste glasses. Results are used to discuss mechanisms and parameters integrated in alteration models of conditioning materials. Glass is a disordered material defined thermodynamically as a non-equilibrium state. Taking into account one order parameter to characterise its configurational state, the metastable equilibrium for the glass was considered and the main thermochemical properties were determined. Calorimetric techniques were used to measure heat capacities and formation enthalpies of borosilicate glasses (from 3 to 8 constitutive oxides). Formation Entropies were measured too, using the entropy theory of relaxation processes proposed by Adam and Gibbs (1965). The configurational entropy contribution were determined from viscosity measurements. This set of data has allowed the calculation of Gibb's free energies of dissolution of glasses in pure water. By comparison with leaching experiments, it has been demonstrated that the decreasing of the dissolution rate at high reaction progress cannot be associated to the approach of an equilibrium between the sound glass and the aqueous solution. The composition changes of the reaction area at the glass surface need to be considered too. To achieve a complete description of the thermodynamic stability, the equilibrium between hydrated de-alkalinized glass and/or the gel layer with the aqueous solution should also be evaluated. (author)

  11. Antagonist effects of calcium on borosilicate glass alteration

    Science.gov (United States)

    Mercado-Depierre, S.; Angeli, F.; Frizon, F.; Gin, S.

    2013-10-01

    Numerous studies have been conducted on glass and cement durability in contact with water, but very little work to date has focused directly on interactions between the two materials. These interactions are mostly controlled by silicon-calcium reactivity. However, the physical and chemical processes involved remain insufficiently understood to predict the evolution of coupled glass-cement systems used in several industrial applications. Results are reported from borosilicate glass alteration in calcium-rich solutions. Our data show that four distinct behaviors can be expected according to the relative importance of three key parameters: the pH, the reaction progress (short- or long-term alteration) and the calcium concentration. Glass alteration is thus controlled by specific mechanisms depending on the solution chemistry: calcium complexation at the glass surface, precipitation of calcium silicate hydrates (C-S-H) or calcium incorporation in the altered layer. These findings highlight the impact of silicon-calcium interactions on glass durability and open the way for a better understanding of glass-cement mixing in civil engineering applications as well as in nuclear waste storage.

  12. Antagonist effects of calcium on borosilicate glass alteration

    Energy Technology Data Exchange (ETDEWEB)

    Mercado-Depierre, S. [CEA Marcoule, DTCD SPDE LCLT, 30207 Bagnols sur Cèze (France); Angeli, F., E-mail: frederic.angeli@cea.fr [CEA Marcoule, DTCD SPDE LCLT, 30207 Bagnols sur Cèze (France); Frizon, F. [CEA Marcoule, DTCD SECM LP2C, 30207 Bagnols sur Cèze (France); Gin, S. [CEA Marcoule, DTCD SPDE LCLT, 30207 Bagnols sur Cèze (France)

    2013-10-15

    Graphical abstract: Display Omitted -- Highlights: •Kinetic study of glass alteration is investigated in calcium-enriched solutions. •New insights into silicon–calcium interactions in glass/cement systems are proposed. •Glass alteration is controlled by pH, Ca concentration and reaction progress. •Evidence of antagonist effects according to the importance of these parameters. -- Abstract: Numerous studies have been conducted on glass and cement durability in contact with water, but very little work to date has focused directly on interactions between the two materials. These interactions are mostly controlled by silicon–calcium reactivity. However, the physical and chemical processes involved remain insufficiently understood to predict the evolution of coupled glass–cement systems used in several industrial applications. Results are reported from borosilicate glass alteration in calcium-rich solutions. Our data show that four distinct behaviors can be expected according to the relative importance of three key parameters: the pH, the reaction progress (short- or long-term alteration) and the calcium concentration. Glass alteration is thus controlled by specific mechanisms depending on the solution chemistry: calcium complexation at the glass surface, precipitation of calcium silicate hydrates (C–S–H) or calcium incorporation in the altered layer. These findings highlight the impact of silicon–calcium interactions on glass durability and open the way for a better understanding of glass–cement mixing in civil engineering applications as well as in nuclear waste storage.

  13. Selective adsorption and release of cationic organic dye molecules on mesoporous borosilicates

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Manidipa; Pal, Nabanita; Bhaumik, Asim, E-mail: msab@iacs.res.in

    2012-08-01

    Mesoporous materials can play a pivotal role as a host material for delivery application to a specific part of a system. In this work we explore the selective adsorption and release of cationic organic dye molecules such as safranine T (ST) and malachite green (MG) on mesoporous borosilicate materials. The mesoporous silica SBA-15 and borosilicate materials (MBS) were prepared using non-ionic surfactant Pluronic P123 as template via evaporation induced self-assembly (EISA) method. After template removal the materials show high surface areas and in some cases ordered mesopores of dimensions ca. 6-7 nm. High surface area, mesoporosity and the presence of heteroatom (boron) help this mesoporous borosilicate material to adsorb high amount of cationic dye molecules at its surface from the respective aqueous solutions. Furthermore, the mesoporous borosilicate samples containing higher percentage adsorbed dyes show excellent release of ST or MG dye in simulated body fluid (SBF) solution at physiological pH = 7.4 and temperature 310 K. The adsorption and release efficiency of mesoporous borosilicate samples are compared with reference boron-free mesoporous pure silica material to understand the nature of adsorbate-adsorbent interaction at the surfaces. - Graphical abstract: Highly ordered 2D-hexagonal mesoporous borosilicate materials have been synthesized by using Pluronic P123 as template. The materials show very good adsorption and release of organic cationic dye molecules under physiological conditions. Highlights: Black-Right-Pointing-Pointer Highly ordered 2D-hexagonal mesoporous borosilicate. Black-Right-Pointing-Pointer Nonionic Pluoronic P123 templated mesoporous material. Black-Right-Pointing-Pointer Adsorption of organic dyes at the mesopore surface. Black-Right-Pointing-Pointer Controlled release of dyes under physiological pH and temperature. Black-Right-Pointing-Pointer Release of safranine T (ST) and malachite green (MG) dyes in simulated body fluids.

  14. Dynamic fracture and fragmentation patterns of borosilicate laminate glasses

    Directory of Open Access Journals (Sweden)

    Gómez del Río, T.

    2009-10-01

    Full Text Available The dynamic behaviour of laminate borosilicate glasses (BSG with polyvinylbutiral (PVB interfaces (0,38 mm located at different distances from the impact point have been studied and compared with monolithic glass. The mechanical behaviour under impact loads have been studied using a compression split Hopkinson pressure bar (SHPB. In these experiments, the stress-strain curves of the materials at high loading rates and the capability of transmitting and reflecting the impact energy have been determined. The influence of the position of the interface on the fragmentation statistics of the SHPB recovered fragments has also been considered and analysed according to the published theoretical models.

    En este trabajo se ha estudiado los comportamientos dinámicos de un vidrio monolítico de borosilicato y varios laminados de cristal de borosilicato (BSG con intercaras de polyvinylbutiral (PVB (0,38 mm situados a diferentes distancias respecto del punto de impacto. Los resultados de las diferentes configuraciones de laminados se han comparado con el vidrio monolítico. El comportamiento mecánico bajo cargas de impacto se han estudiado realizando ensayos de compresión con una barra Hopkinson (SHPB. A partir de estos experimentos se obtienen las curvas tensión-deformación de los materiales a altas velocidades de carga y su capacidad de transmitir y reflejar la energía del impacto. La influencia de la posición de la interfaz en las estadísticas de la fragmentación de los fragmentos recuperados también se ha considerado y analizado de acuerdo a los modelos teóricos publicados.

  15. Atomic layer deposited borosilicate glass microchannel plates for large area event counting detectors

    International Nuclear Information System (INIS)

    Siegmund, O.H.W.; McPhate, J.B.; Tremsin, A.S.; Jelinsky, S.R.; Hemphill, R.; Frisch, H.J.; Elam, J.; Mane, A.

    2012-01-01

    Borosilicate glass micro-capillary array substrates with 20 μm and 40 μm pores have been deposited with resistive, and secondary electron emissive, layers by atomic layer deposition to produce functional microchannel plates. Device formats of 32.7 mm and 20 cm square have been fabricated and tested in analog and photon counting modes. The tests show amplification, imaging, background rate, pulse shape and lifetime characteristics that are comparable to standard glass microchannel plates. Large area microchannel plates of this type facilitate the construction of 20 cm format sealed tube sensors with strip-line readouts that are being developed for Cherenkov light detection. Complementary work has resulted in Na 2 KSb bialkali photocathodes with peak quantum efficiency of 25% being made on borosilicate glass. Additionally GaN (Mg) opaque photocathodes have been successfully made on borosilicate microchannel plates.

  16. Atomic layer deposited borosilicate glass microchannel plates for large area event counting detectors

    Science.gov (United States)

    Siegmund, O. H. W.; McPhate, J. B.; Tremsin, A. S.; Jelinsky, S. R.; Hemphill, R.; Frisch, H. J.; Elam, J.; Mane, A.; Lappd Collaboration

    2012-12-01

    Borosilicate glass micro-capillary array substrates with 20 μm and 40 μm pores have been deposited with resistive, and secondary electron emissive, layers by atomic layer deposition to produce functional microchannel plates. Device formats of 32.7 mm and 20 cm square have been fabricated and tested in analog and photon counting modes. The tests show amplification, imaging, background rate, pulse shape and lifetime characteristics that are comparable to standard glass microchannel plates. Large area microchannel plates of this type facilitate the construction of 20 cm format sealed tube sensors with strip-line readouts that are being developed for Cherenkov light detection. Complementary work has resulted in Na2KSb bialkali photocathodes with peak quantum efficiency of 25% being made on borosilicate glass. Additionally GaN (Mg) opaque photocathodes have been successfully made on borosilicate microchannel plates.

  17. Effect of heat treatment duration on phase separation of sodium borosilicate glass, containing copper

    International Nuclear Information System (INIS)

    Shejnina, T.G.; Gutner, S.Kh.; Anan'in, N.I.

    1989-01-01

    The effect of heat treatment duration on phase separation of sodium borosilicate (SBS) glass, containing copper is studied. It is stated that phase separation close to equilibrium one is attained under 12 hours of heat treatment of SBS glass containing copper

  18. Chapter 1. The characteristics of borosilicate ores of Ak-Arkhar Deposit of Tajikistan

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.; Kurbonov, A.S.; Mamatov, E.D.

    2015-01-01

    Present article is devoted to characteristics of borosilicate ores of Ak-Arkhar Deposit of Tajikistan. The chemical composition of danburite ore of Ak-Arkhar Deposit was defined. The chemical composition of danburite ore concentrate of Ak-Arkhar Deposit was defined as well.

  19. Modelling the evaporation of boron species. Part 1: Alkali-free borosilicate glass melts

    NARCIS (Netherlands)

    Limpt, J.A.C. van; Beerkens, R.G.C.; Cook, S.; O'Connor, R.; Simon, J.

    2011-01-01

    A laboratory test facility has been used to measure the boron evaporation rates from borosilicate glass melts. The impact of furnace atmosphere composition and glass melt composition on the temperature dependent boron evaporation rates has been investigated experimentally. In Part 1 of this paper

  20. X-ray tomography of feed-to-glass transition of simulated borosilicate waste glasses

    Czech Academy of Sciences Publication Activity Database

    Harris, W.H.; Guillen, D.P.; Kloužek, Jaroslav; Pokorný, P.; Yano, T.; Lee, S.; Schweiger, M. J.; Hrma, P.

    2017-01-01

    Roč. 100, č. 9 (2017), s. 3883-3894 ISSN 0002-7820 Institutional support: RVO:67985891 Keywords : borosilicate glass * computed tomography * glass melting * morphology * nuclear waste * X-ray Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass OBOR OECD: Ceramics Impact factor: 2.841, year: 2016

  1. Quantification of the boron speciation in alkali borosilicate glasses by electron energy loss spectroscopy

    DEFF Research Database (Denmark)

    Cheng, D.S.; Yang, G.; Zhao, Y.Q.

    2015-01-01

    developed a method based on electron energy loss spectroscopy (EELS) data acquisition and analyses, which enables determination of the boron speciation in a series of ternary alkali borosilicate glasses with constant molar ratios. A script for the fast acquisition of EELS has been designed, from which...

  2. Evaluation of the borosilicate glass matrix for the immobilization of actinide waste concentrates

    International Nuclear Information System (INIS)

    Scheffler, K.; Krause, H.

    1978-01-01

    During liquid storage of HLLW the formation of actinide enriched sludges is being expected due to the hydrolysis esp. of plutonium and other mechanisms. Also during melting of HLW glasses an increase of top-to-bottom actinide concentration can take place. Both effects will account for increased actinide concentrations in the glasses. The phenomena of these actinide enrichment processes are studied. Following the investigations on actinide compatibility with HLW glass a research program has been started aiming at the vitrification of special actinide waste concentrates. A hazards evaluation is established on the basis of experimental results for simulated disposal periods of millenia with respect to leaching of actinides and alpha irradiation damage. The chemical compatibility of borosilicate glass with actinides has been determined and basic considerations are drawn for the solidification of different types of alpha-bearing wastes in borosilicate glasses

  3. Ultra-Lightweight Borosilicate Gas-Fusion Mirror for Cryogenic Testing

    Science.gov (United States)

    Voevodsky, Michael

    2003-01-01

    Hextek Corporation fabricated a 250 mm diameter ultra-lightweight borosilicate mirror substrate for cryogenic testing at NASA MSFC XRCF facility in Huntsville AL under contract# H-34475D. The objectives of the program were to demonstrate that the Hextek Gas-Fusion technology is capable of meeting the 15kg/sq m areal density target required for future space missions, and to provide a demonstration substrate for NASA MSFC to finish and test at cryogenic temperature. This presentation reviews company background and capabilities, features and benefits of the Gas-Fusion technology, historical data on cryogenic performance of borosilicate glass showing near zero cte at 30-35 degrees Kelvin, design and fabrication results of the 250 mm 15kg/sq m areal density substrate, and finally, projected scaling, lightweighing and fabrication lead-times for meter class segments.

  4. Proving the role of boron in the structure of fly-ash/borosilicate glass based geopolymers

    Czech Academy of Sciences Publication Activity Database

    Taveri, Gianmarco; Toušek, J.; Bernardo, E.; Toniolo, N.; Boccaccini, A. R.; Dlouhý, Ivo

    2017-01-01

    Roč. 200, AUG (2017), s. 105-108 ISSN 0167-577X EU Projects: European Commission(XE) 642557 - CoACH Institutional support: RVO:68081723 Keywords : Fly-ash * Borosillicate * Geopolymerization * Spectroscopy * NMR * FTIR Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass OBOR OECD: Ceramics Impact factor: 2.572, year: 2016 http://www.sciencedirect.com/science/article/pii/S0167577X1730650X

  5. Influence of Cu doping in borosilicate bioactive glass and the properties of its derived scaffolds.

    Science.gov (United States)

    Wang, Hui; Zhao, Shichang; Xiao, Wei; Xue, Jingzhe; Shen, Youqu; Zhou, Jie; Huang, Wenhai; Rahaman, Mohamed N; Zhang, Changqing; Wang, Deping

    2016-01-01

    Copper doped borosilicate glasses (BG-Cu) were studied by means of FT-IR, Raman, UV-vis and NMR spectroscopies to investigate the changes that appeared in the structure of borosilicate glass matrix by doping copper ions. Micro-fil and immunohistochemistry analysis were applied to study the angiogenesis of its derived scaffolds in vivo. Results indicated that the Cu ions significantly increased the B-O bond of BO4 groups at 980 cm(-1), while they decrease that of BO2O(-) groups at 1440-1470 cm(-1) as shown by Raman spectra. A negative shift was observed from (11)B and (29)Si NMR spectra. The (11)B NMR spectra exhibited a clear transformation from BO3 into BO4 groups, caused by the agglutination effect of the Cu ions and the charge balance of the agglomerate in the glass network, leading to a more stable glass network and lower ions release rate in the degradation process. Furthermore, the BG-Cu scaffolds significantly enhanced blood vessel formation in rat calvarial defects at 8 weeks post-implantation. Generally, it suggested that the introduction of Cu into borosilicate glass endowed glass and its derived scaffolds with good properties, and the cooperation of Cu with bioactive glass may pave a new way for tissue engineering. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Phase separation of borosilicate glass with molybdenum oxide addition and pore structure of porous glass

    International Nuclear Information System (INIS)

    Tanaka, Hiroshi; Yazawa, Tetsuo; Eguchi, Kiyohisa

    1985-01-01

    Porous glass prepared by acid leaching of phase-separated soda borosilicate glass usually contains colloidal silica which originates from the silica component in the borate phase. Molybdenum trioxide was added to the starting borosilicate glass to prevent the formation of colloidal silica. It promoted the opacification of the starting glass. Opaque glasses in as-cast state showed a spherical phase-separated structure and were amorphous by X-ray doffraction. The phase separation was related to the solubility of molybdenum oxide in the glass. The phase separation occurs at a high temperature and proceeds rapidly in the cooling process of the cast glass. Another type of phase separation, which was assigned to the phase separation in the ternary soda borosilicate glass, took place during the heat treatment of the opaque glasses. When the phase-separated structure of the heat-treated glasses is interconnected, the porous glasses composed of silica skeleton are obtained by the acid leaching of the phase-separated glasses. The colloidal silica in the porous glass increased with increasing silica content of the starting glass and at the same time the volume of the pores of skeleton decreased markedly. (author)

  7. X-ray absorption and Raman spectroscopy studies of molybdenum environments in borosilicate waste glasses

    Science.gov (United States)

    McKeown, David A.; Gan, Hao; Pegg, Ian L.

    2017-05-01

    Mo-containing high-level nuclear waste borosilicate glasses were investigated as part of an effort to improve Mo loading while avoiding yellow phase crystallization. Previous work showed that additions of vanadium decrease yellow phase formation and increases Mo solubility. X-ray absorption spectroscopy (XAS) and Raman spectroscopy were used to characterize Mo environments in HLW borosilicate glasses and to investigate possible structural relationships between Mo and V. Mo XAS spectra for the glasses indicate isolated tetrahedral Mo6+O4 with Mo-O distances near 1.75 Å. V XANES indicate tetrahedral V5+O4 as the dominant species. Raman spectra show composition dependent trends, where Mo-O symmetrical stretch mode frequencies (ν1) are sensitive to the mix of alkali and alkaline earth cations, decreasing by up to 10 cm-1 for glasses that change from Li+ to Na+ as the dominant network-modifying species. This indicates that MoO4 tetrahedra are isolated from the borosilicate network and are surrounded, at least partly, by Na+ and Li+. Secondary ν1 frequency effects, with changes up to 7 cm-1, were also observed with increasing V2O5 and MoO3 content. These secondary trends may indicate MoO4-MoO4 and MoO4-VO4 clustering, suggesting that V additions may stabilize Mo in the matrix with respect to yellow phase formation.

  8. Preliminary assessment of modified borosilicate glasses for chromium and ruthenium immobilization

    Energy Technology Data Exchange (ETDEWEB)

    Farid, Osama M. [Reactors Department, Nuclear Research Center, Atomic Energy Authority of Egypt, P.O. 13759, Inshas, Cairo (Egypt); Centre of Nuclear Engineering (CNE), Department of Materials, Imperial College London, London, SW7 2BP (United Kingdom); Abdel Rahman, R.O., E-mail: alaarehab@yahoo.com [Hot Laboratory Center, Atomic Energy Authority of Egypt, P.O. 13759, Inshas, Cairo (Egypt)

    2017-01-15

    The feasibility of using modified alkali borosilicate glasses for ruthenium and chromium immobilization is preliminary assessed by investigating the immobilization system structure under normal conditions. Within this context, reference alkali borosilicate, and simulated Magnox-modified glasses were prepared and studied. The results indicate that ruthenium is immobilized in the vitreous structure as encapsulated RuO{sub 2} crystallites that act as seeds for heterogeneous nucleation of other crystalline phases. The presence of Zn, as modifier, has contributed to chromium immobilization in zincochromite spinel structure, whereas Ca is accommodated in the vitreous structure. Immobilization performance was evaluated by conducting conservative static leach test and studying the leached glass. Leached glass morphology was altered, where near surface reference glass is leached over 400 nm and simulated Magnox-modified sample is altered over 300 nm. Normalized release rates are within normal range for borosilicate material. For simulated Magnox-modified sample, Ca and alkali structural element, i.e. Na and Li, are leached via ion-exchange reaction. The ion-exchanged fraction equals 1.06 × 10{sup −8} mol/m{sup 2} s and chromium has slightly lower normalized release rate value than ruthenium. - Highlights: • The presence of modifiers and waste oxides led to localized de-vitrification. • Ruthenium is encapsulated within the vitreous glass network as RuO{sub 2} crystals. • Chromium is immobilized within the zincochromite spinel structure. • Pitting and cracks induced by leaching did not affect the immobilization performance.

  9. Comparison of hardness variation of ion irradiated borosilicate glasses with different projected ranges

    Science.gov (United States)

    Sun, M. L.; Peng, H. B.; Duan, B. H.; Liu, F. F.; Du, X.; Yuan, W.; Zhang, B. T.; Zhang, X. Y.; Wang, T. S.

    2018-03-01

    Borosilicate glass has potential application for vitrification of high-level radioactive waste, which attracts extensive interest in studying its radiation durability. In this study, sodium borosilicate glass samples were irradiated with 4 MeV Kr17+ ion, 5 MeV Xe26+ ion and 0.3 MeV P+ ion, respectively. The hardness of irradiated borosilicate glass samples was measured with nanoindentation in continuous stiffness mode and quasi continuous stiffness mode, separately. Extrapolation method, mean value method, squared extrapolation method and selected point method are used to obtain hardness of irradiated glass and a comparison among these four methods is conducted. The extrapolation method is suggested to analyze the hardness of ion irradiated glass. With increasing irradiation dose, the values of hardness for samples irradiated with Kr, Xe and P ions dropped and then saturated at 0.02 dpa. Besides, both the maximum variations and decay constants for three kinds of ions with different energies are similar indicates the similarity behind the hardness variation in glasses after irradiation. Furthermore, the hardness variation of low energy P ion irradiated samples whose range is much smaller than those of high energy Kr and Xe ions, has the same trend as that of Kr and Xe ions. It suggested that electronic energy loss did not play a significant role in hardness decrease for irradiation of low energy ions.

  10. High-level waste borosilicate glass a compendium of corrosion characteristics. Volume 1

    International Nuclear Information System (INIS)

    Cunnane, J.C.

    1994-03-01

    Current plans call for the United States Department of Energy (DOE) to start up facilities for vitrification of high-level radioactive waste (HLW) stored in tanks at the Savannah River Site, Aiken, South Carolina, in 1995; West Valley Demonstration Project, West Valley, New York, in 1996; and at the Hanford Site, Richland, Washington, after the year 2000. The product from these facilities will be canistered HLW borosilicate glass, which will be stored, transported, and eventually disposed of in a geologic repository. The behavior of this glass waste product, under the range of likely service conditions, is the subject of considerable scientific and public interest. Over the past few decades, a large body of scientific information on borosilicate waste glass has been generated worldwide. The intent of this document is to consolidate information pertaining to our current understanding of waste glass corrosion behavior and radionuclide release. The objective, scope, and organization of the document are discussed in Section 1.1, and an overview of borosilicate glass corrosion is provided in Section 1.2. The history of glass as a waste form and the international experience with waste glass are summarized in Sections 1.3 and 1.4, respectively

  11. Fabrication of Low Noise Borosilicate Glass Nanopores for Single Molecule Sensing.

    Directory of Open Access Journals (Sweden)

    Jayesh A Bafna

    Full Text Available We show low-cost fabrication and characterization of borosilicate glass nanopores for single molecule sensing. Nanopores with diameters of ~100 nm were fabricated in borosilicate glass capillaries using laser assisted glass puller. We further achieve controlled reduction and nanometer-size control in pore diameter by sculpting them under constant electron beam exposure. We successfully fabricate pore diameters down to 6 nm. We next show electrical characterization and low-noise behavior of these borosilicate nanopores and compare their taper geometries. We show, for the first time, a comprehensive characterization of glass nanopore conductance across six-orders of magnitude (1M-1μM of salt conditions, highlighting the role of buffer conditions. Finally, we demonstrate single molecule sensing capabilities of these devices with real-time translocation experiments of individual λ-DNA molecules. We observe distinct current blockage signatures of linear as well as folded DNA molecules as they undergo voltage-driven translocation through the glass nanopores. We find increased signal to noise for single molecule detection for higher trans-nanopore driving voltages. We propose these nanopores will expand the realm of applications for nanopore platform.

  12. High-level waste borosilicate glass a compendium of corrosion characteristics. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Cunnane, J.C. [comp.; Bates, J.K.; Bradley, C.R. [Argonne National Lab., IL (United States)

    1994-03-01

    Current plans call for the United States Department of Energy (DOE) to start up facilities for vitrification of high-level radioactive waste (HLW) stored in tanks at the Savannah River Site, Aiken, South Carolina, in 1995; West Valley Demonstration Project, West Valley, New York, in 1996; and at the Hanford Site, Richland, Washington, after the year 2000. The product from these facilities will be canistered HLW borosilicate glass, which will be stored, transported, and eventually disposed of in a geologic repository. The behavior of this glass waste product, under the range of likely service conditions, is the subject of considerable scientific and public interest. Over the past few decades, a large body of scientific information on borosilicate waste glass has been generated worldwide. The intent of this document is to consolidate information pertaining to our current understanding of waste glass corrosion behavior and radionuclide release. The objective, scope, and organization of the document are discussed in Section 1.1, and an overview of borosilicate glass corrosion is provided in Section 1.2. The history of glass as a waste form and the international experience with waste glass are summarized in Sections 1.3 and 1.4, respectively.

  13. A Raman spectroscopy study on the effects of intermolecular hydrogen bonding on water molecules absorbed by borosilicate glass surface

    Science.gov (United States)

    Li, Fabing; Li, Zhanlong; Wang, Ying; Wang, Shenghan; Wang, Xiaojun; Sun, Chenglin; Men, Zhiwei

    2018-05-01

    The structural forms of water/deuterated water molecules located on the surface of borosilicate capillaries have been first investigated in this study on the basis of the Raman spectral data obtained at different temperatures and under atmospheric pressure for molecules in bulk and also for molecules absorbed by borosilicate glass surface. The strongest two fundamental bands locating at 3063 cm-1 (2438 cm-1) in the recorded Raman spectra are assigned here to the Osbnd H (Osbnd D) bond stretching vibrations and they are compared with the corresponding bands observed at 3124 cm-1 (2325 cm-1) in the Raman spectrum of ice Ih. Our spectroscopic observations have indicated that the structure of water and deuterated water molecules on borosilicate surface is similar to that of ice Ih (hexagonal phase of ice). These observations have also indicated that water molecules locate on the borosilicate surface so as to construct a bilayer structure and that strong and weak intermolecular hydrogen bonds are formed between water/deuterated molecules and silanol groups on borosilicate surface. In accordance with these findings, water and deuterated water molecules at the interface of capillary have a higher melting temperature.

  14. A Raman spectroscopy study on the effects of intermolecular hydrogen bonding on water molecules absorbed by borosilicate glass surface.

    Science.gov (United States)

    Li, Fabing; Li, Zhanlong; Wang, Ying; Wang, Shenghan; Wang, Xiaojun; Sun, Chenglin; Men, Zhiwei

    2018-05-05

    The structural forms of water/deuterated water molecules located on the surface of borosilicate capillaries have been first investigated in this study on the basis of the Raman spectral data obtained at different temperatures and under atmospheric pressure for molecules in bulk and also for molecules absorbed by borosilicate glass surface. The strongest two fundamental bands locating at 3063cm -1 (2438cm -1 ) in the recorded Raman spectra are assigned here to the OH (OD) bond stretching vibrations and they are compared with the corresponding bands observed at 3124cm -1 (2325cm -1 ) in the Raman spectrum of ice Ih. Our spectroscopic observations have indicated that the structure of water and deuterated water molecules on borosilicate surface is similar to that of ice Ih (hexagonal phase of ice). These observations have also indicated that water molecules locate on the borosilicate surface so as to construct a bilayer structure and that strong and weak intermolecular hydrogen bonds are formed between water/deuterated molecules and silanol groups on borosilicate surface. In accordance with these findings, water and deuterated water molecules at the interface of capillary have a higher melting temperature. Copyright © 2018. Published by Elsevier B.V.

  15. Water leaching of borosilicate glasses: experiments, modeling and Monte Carlo simulations; Alteration par l'eau des verres borosilicates: experiences, modelisation et simulations Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Ledieu, A

    2004-10-15

    This work is concerned with the corrosion of borosilicate glasses with variable oxide contents. The originality of this study is the complementary use of experiments and numerical simulations. This study is expected to contribute to a better understanding of the corrosion of nuclear waste confinement glasses. First, the corrosion of glasses containing only silicon, boron and sodium oxides has been studied. The kinetics of leaching show that the rate of leaching and the final degree of corrosion sharply depend on the boron content through a percolation mechanism. For some glass contents and some conditions of leaching, the layer which appears at the glass surface stops the release of soluble species (boron and sodium). This altered layer (also called the gel layer) has been characterized with nuclear magnetic resonance (NMR) and small angle X-ray scattering (SAXS) techniques. Second, additional elements have been included in the glass composition. It appears that calcium, zirconium or aluminum oxides strongly modify the final degree of corrosion so that the percolation properties of the boron sub-network is no more a sufficient explanation to account for the behavior of these glasses. Meanwhile, we have developed a theoretical model, based on the dissolution and the reprecipitation of the silicon. Kinetic Monte Carlo simulations have been used in order to test several concepts such as the boron percolation, the local reactivity of weakly soluble elements and the restructuring of the gel layer. This model has been fully validated by comparison with the results on the three oxide glasses. Then, it has been used as a comprehensive tool to investigate the paradoxical behavior of the aluminum and zirconium glasses: although these elements slow down the corrosion kinetics, they lead to a deeper final degree of corrosion. The main contribution of this work is that the final degree of corrosion of borosilicate glasses results from the competition of two opposite mechanisms

  16. Aqueous corrosion of borosilicate glasses: experiments, modeling and Monte-Carlo simulations; Alteration par l'eau des verres borosilicates: experiences, modelisation et simulations Monte-Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Ledieu, A

    2004-10-01

    This work is concerned with the corrosion of borosilicate glasses with variable oxide contents. The originality of this study is the complementary use of experiments and numerical simulations. This study is expected to contribute to a better understanding of the corrosion of nuclear waste confinement glasses. First, the corrosion of glasses containing only silicon, boron and sodium oxides has been studied. The kinetics of leaching show that the rate of leaching and the final degree of corrosion sharply depend on the boron content through a percolation mechanism. For some glass contents and some conditions of leaching, the layer which appears at the glass surface stops the release of soluble species (boron and sodium). This altered layer (also called the gel layer) has been characterized with nuclear magnetic resonance (NMR) and small angle X-ray scattering (SAXS) techniques. Second, additional elements have been included in the glass composition. It appears that calcium, zirconium or aluminum oxides strongly modify the final degree of corrosion so that the percolation properties of the boron sub-network is no more a sufficient explanation to account for the behavior of these glasses. Meanwhile, we have developed a theoretical model, based on the dissolution and the reprecipitation of the silicon. Kinetic Monte Carlo simulations have been used in order to test several concepts such as the boron percolation, the local reactivity of weakly soluble elements and the restructuring of the gel layer. This model has been fully validated by comparison with the results on the three oxide glasses. Then, it has been used as a comprehensive tool to investigate the paradoxical behavior of the aluminum and zirconium glasses: although these elements slow down the corrosion kinetics, they lead to a deeper final degree of corrosion. The main contribution of this work is that the final degree of corrosion of borosilicate glasses results from the competition of two opposite mechanisms

  17. Advances in understanding the structure of borosilicate glasses: A Raman spectroscopy study

    Energy Technology Data Exchange (ETDEWEB)

    Manara, D.; Grandjean, A. [CEA Marcoule, Serv Confinement Deches and Vitrificat, DTCD, DEN - 30 (France); Neuville, D.R. [Institut Physique Globe, Physique des Mineraux et Magmas, CNRS, F-75252 Paris 05 (France)

    2009-05-15

    This study is focused on the behavior of ternary SiO{sub 2}-Na{sub 2}O-B{sub 2}O{sub 3} borosilicate glasses at temperatures between 298 and 1800 K. Unpolarized Raman spectra were measured up to high temperature. SiO{sub 2}-Na{sub 2}O-B{sub 2}O{sub 3} glass samples were prepared with different values of the ratio R [Na{sub 2}O]/[B{sub 2}O{sub 3}], while the ratio K = [SiO{sub 2}]/[B{sub 2}O{sub 3}] was kept constant and equal 2.12. Spectra were measured at room temperature in samples with 0.43 {<=} R {<=} 1.68, and the effect of the modifier content was clearly observed in these glasses, only in partial agreement with previous literature results. In particular, the formation in the glass of sodium-danburite units Na{sub 2}O-B{sub 2}O{sub 3}-2SiO{sub 2} was postulated. This feature led to a new assessment of R{sup *}, the critical value of R above which every new alkali atom added to the system breaks a Fo-O-Fo (Fo=glass former) bridge causing depolymerization of the glass. A revised formula is proposed to obtain the value of R{sup *} as a function of K. Raman spectra measured at high temperature yielded important information about the temperature-dependent evolution of the borosilicate system. In particular, borate and borosilicate units including tetra-coordinated boron seem to be unstable at high temperature, where the formation of metaborate chains or rings is fostered. Above 1500 degrees C, evaporation of borate compounds is clearly observed, stemming from the small sample size. (authors)

  18. Photoelastic examination of borosilicate glass discs used in the insulating legs for the NSF tandem

    International Nuclear Information System (INIS)

    Acton, W.J.; Cundy, D.

    1981-04-01

    The results are presented of a photoelastic stress analysis carried out to establish the effect of re-annealing borosilicate glass discs used in the insulating legs of the 30 MV tandem van de Graaff accelerator of the NSF. The results show that re-annealing of the glass discs has no measurable effect on reducing the high stress at inclusions and re-emphasise the need to exercise great care in selecting suitable discs for use in the insulating legs. (U.K.)

  19. Influence of iron ions on the structural properties of Zn-borosilicate glasses

    International Nuclear Information System (INIS)

    Music, S.; Gotic, M.; Popovic, S.

    1989-01-01

    The objectives of this study were to determine the influence of iron ions on the appearance of crystalline phases in Zn-borosilicate glasses, and to obtain information about valence state and coordination of iron ions. The systems Na 2 O-ZnO-B 2 O 3 -SiO 2 and ZnO-B 2 O 3 -SiO 2 were doped with α-Fe 2 O 3 . X-ray diffraction, IR spectroscopy and 57 Fe Moessbauer spectroscopy were used as experimental techniques. (author) 32 refs.; 5 figs.; 5 tabs

  20. New insight into nanoparticle precipitation by electron beams in borosilicate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Sabri, M.M.; Moebus, G. [University of Sheffield, Department of Materials Science and Engineering (United Kingdom)

    2017-06-15

    Nanoprecipitation in different oxide glasses by means of electron irradiation in transmission electron microscopy (TEM) has been compared in this study. Upon irradiation, groups or patterns of nanoparticles with various morphologies and sizes were formed in borosilicate glasses, loaded with zinc, copper, and silver. The study successfully includes loading ranges for the target metal from doping level (1%) over medium level (20%) to majority phase (60%). It is found that particle patterning resolution is affected by parallel processes of amorphous phase separation, glass ablation, and delocalised precipitation. In addition, via an in-situ study, it is confirmed that by heating alone without irradiation, no precipitate nanoparticles form. (orig.)

  1. Structural investigations of bismuth lead borosilicate glasses under the influence of gamma irradiation through ultrasonic studies

    Science.gov (United States)

    Bootjomchai, Cherdsak; Laopaiboon, Jintana; Laopaiboon, Raewat

    2012-04-01

    The ultrasonic velocity measurements for different compositions of irradiated bismuth lead borosilicate glasses xBi2O3-(50-x)PbO-20B2O3-30SiO2 (x=2, 4, 6, 8, and 10 mol.%) were performed at room temperature using pulse-echo technique. Densities of glass samples were measured by Archimedes' principle using n-hexane as the immersion liquid. The results from the studies show that ultrasonic velocity, elastic moduli, Poisson's ratio, microhardness, and the Debye temperature increase with increasing bismuth oxide content and increasing gamma-radiation dose (3-12 Gy).

  2. Study of Structural Properties of Mesoporous Carbon From Fructose with Zinc Borosilicate Activator

    OpenAIRE

    Setianingsih, Tutik; Kartini, Indriana; Arryanto, Yateman

    2014-01-01

    Structural properties, including pore structure, functional group of carbon surface, and crystal structure of carbon built by zinc borosilicate (ZBS) and ZnCl2 (Z) have been investigated in this work. Physically, ZBS and ZnCl2 may act as template of carbon, whereas the Zn(II) cation act as chemical activator of carbonization. All precursors of ZBS (silicagel, boric acid, and ZnCl2) may act as catalysts of caramelization. The caramelization was conducted hydrothermally at 85oC and thermally 1...

  3. High-level waste borosilicate glass: A compendium of corrosion characteristics. Volume 3

    International Nuclear Information System (INIS)

    Cunnane, J.C.

    1994-03-01

    The objective of this document is to summarize scientific information pertinent to evaluating the extent to which high-level waste borosilicate glass corrosion and the associated radionuclide release processes are understood for the range of environmental conditions to which waste glass may be exposed in service. Alteration processes occurring within the bulk of the glass (e.g., devitrification and radiation-induced changes) are discussed insofar as they affect glass corrosion. Volume III contains a bibliography of glass corrosion studies, including studies that are not cited in Volumes I and II

  4. High-level waste borosilicate glass: A compendium of corrosion characteristics. Volume 3

    Energy Technology Data Exchange (ETDEWEB)

    Cunnane, J.C. [comp.; Bates, J.K.; Bradley, C.R. [Argonne National Lab., IL (United States)] [and others

    1994-03-01

    The objective of this document is to summarize scientific information pertinent to evaluating the extent to which high-level waste borosilicate glass corrosion and the associated radionuclide release processes are understood for the range of environmental conditions to which waste glass may be exposed in service. Alteration processes occurring within the bulk of the glass (e.g., devitrification and radiation-induced changes) are discussed insofar as they affect glass corrosion. Volume III contains a bibliography of glass corrosion studies, including studies that are not cited in Volumes I and II.

  5. A review of phase separation in borosilicate glasses, with reference to nuclear fuel waste immobilization

    International Nuclear Information System (INIS)

    Taylor, P.

    1990-08-01

    This report reviews information on miscibility limits in borosilicate glass-forming systems. It includes both a literature survey and an account of experimental work performed within the Canadian Nuclear Fuel Waste Management Program. Emphasis is placed on the measurement and depiction of miscibility limits in multicomponent (mainly quaternary) systems, and the effects of individual components on the occurrence of phase separation. The behaviour of the multicomponent system is related to that of simpler (binary and ternary) glass systems. The possible occurrence of phase separation, as well as its avoidance, during processing of nuclear waste glasses is discussed

  6. New insight into nanoparticle precipitation by electron beams in borosilicate glasses

    International Nuclear Information System (INIS)

    Sabri, M.M.; Moebus, G.

    2017-01-01

    Nanoprecipitation in different oxide glasses by means of electron irradiation in transmission electron microscopy (TEM) has been compared in this study. Upon irradiation, groups or patterns of nanoparticles with various morphologies and sizes were formed in borosilicate glasses, loaded with zinc, copper, and silver. The study successfully includes loading ranges for the target metal from doping level (1%) over medium level (20%) to majority phase (60%). It is found that particle patterning resolution is affected by parallel processes of amorphous phase separation, glass ablation, and delocalised precipitation. In addition, via an in-situ study, it is confirmed that by heating alone without irradiation, no precipitate nanoparticles form. (orig.)

  7. New insight into nanoparticle precipitation by electron beams in borosilicate glasses

    Science.gov (United States)

    Sabri, M. M.; Möbus, G.

    2017-06-01

    Nanoprecipitation in different oxide glasses by means of electron irradiation in transmission electron microscopy (TEM) has been compared in this study. Upon irradiation, groups or patterns of nanoparticles with various morphologies and sizes were formed in borosilicate glasses, loaded with zinc, copper, and silver. The study successfully includes loading ranges for the target metal from doping level (1%) over medium level (20%) to majority phase (60%). It is found that particle patterning resolution is affected by parallel processes of amorphous phase separation, glass ablation, and delocalised precipitation. In addition, via an in-situ study, it is confirmed that by heating alone without irradiation, no precipitate nanoparticles form.

  8. Structural analysis of mixed alkali borosilicate glasses containing Cs+ and Na+ using strong magnetic field magic angle spinning nuclear magnetic resonance

    Directory of Open Access Journals (Sweden)

    S. Kaneko

    2017-03-01

    Full Text Available We have investigated the local structure of alkali atoms in mixed alkali silicate, borate, and borosilicate glasses, which contain Cs+ and Na+, using strong magnetic field magic angle spinning nuclear magnetic resonance (MAS NMR spectroscopy of 133Cs and 23Na. The spectral peaks of 133Cs in borosilicate (Si:B = 1:1 and Si-rich borosilicate (Si:B = 2:1 glasses shifted to upfield with increasing Cs+/(Na+ + Cs+ ratio, which implies that the coordination number of Cs+ decreased as in the case of silicate and borate glasses. However, this trend was not observed in the 23Na spectra of either borosilicate glass. This might be because the chemical shift of 23Na in borosilicate glass is strongly affected by nearby species such as Si or B, and not by the coordination number of Na+.

  9. Fabrication of Silicon Nitride Dental Core Ceramics with Borosilicate Veneering material

    International Nuclear Information System (INIS)

    Wananuruksawong, R; Jinawath, S; Wasanapiarnpong, T; Padipatvuthikul, P

    2011-01-01

    Silicon nitride (Si 3 N 4 ) ceramic is a great candidate for clinical applications due to its high fracture toughness, strength, hardness and bio-inertness. This study has focused on the Si 3 N 4 ceramic as a dental core material. The white Si 3 N 4 was prepared by pressureless sintering at relative low sintering temperature of 1650 deg. C in nitrogen atmosphere. The coefficient of thermal expansion (CTE) of Si 3 N 4 ceramic is lower than that of Zirconia and Alumina ceramic which are popular in this field. The borosilicate glass veneering was employed due to its compatibility in thermal expansion. The sintered Si 3 N 4 specimens represented the synthetic dental core were paintbrush coated by a veneer paste composed of borosilicate glass powder ( 2 O 3 - partial stabilized zirconia) and 30 wt% of polyvinyl alcohol (5 wt% solution). After coating the veneer on the Si 3 N 4 specimens, the firing was performed in electric tube furnace between 1000-1200 deg. C. The veneered specimens fired at 1100 deg. C for 15 mins show good bonding, smooth and glossy without defect and crazing. The veneer has thermal expansion coefficient as 3.98x10 -6 deg. C -1 , rather white and semi opaque, due to zirconia addition, the Vickers hardness as 4.0 GPa which is closely to the human teeth.

  10. Fabrication of Silicon Nitride Dental Core Ceramics with Borosilicate Veneering material

    Science.gov (United States)

    Wananuruksawong, R.; Jinawath, S.; Padipatvuthikul, P.; Wasanapiarnpong, T.

    2011-10-01

    Silicon nitride (Si3N4) ceramic is a great candidate for clinical applications due to its high fracture toughness, strength, hardness and bio-inertness. This study has focused on the Si3N4 ceramic as a dental core material. The white Si3N4 was prepared by pressureless sintering at relative low sintering temperature of 1650 °C in nitrogen atmosphere. The coefficient of thermal expansion (CTE) of Si3N4 ceramic is lower than that of Zirconia and Alumina ceramic which are popular in this field. The borosilicate glass veneering was employed due to its compatibility in thermal expansion. The sintered Si3N4 specimens represented the synthetic dental core were paintbrush coated by a veneer paste composed of borosilicate glass powder (<150 micrometer, Pyrex) with 5 wt% of zirconia powder (3 wt% Y2O3 - partial stabilized zirconia) and 30 wt% of polyvinyl alcohol (5 wt% solution). After coating the veneer on the Si3N4 specimens, the firing was performed in electric tube furnace between 1000-1200°C. The veneered specimens fired at 1100°C for 15 mins show good bonding, smooth and glossy without defect and crazing. The veneer has thermal expansion coefficient as 3.98×10-6 °C-1, rather white and semi opaque, due to zirconia addition, the Vickers hardness as 4.0 GPa which is closely to the human teeth.

  11. Rhenium solubility in borosilicate nuclear waste glass: implications for the processing and immobilization of technetium-99.

    Science.gov (United States)

    McCloy, John S; Riley, Brian J; Goel, Ashutosh; Liezers, Martin; Schweiger, Michael J; Rodriguez, Carmen P; Hrma, Pavel; Kim, Dong-Sang; Lukens, Wayne W; Kruger, Albert A

    2012-11-20

    The immobilization of technetium-99 ((99)Tc) in a suitable host matrix has proven to be a challenging task for researchers in the nuclear waste community around the world. In this context, the present work reports on the solubility and retention of rhenium, a nonradioactive surrogate for (99)Tc, in a sodium borosilicate glass. Glasses containing target Re concentrations from 0 to 10,000 ppm [by mass, added as KReO(4) (Re(7+))] were synthesized in vacuum-sealed quartz ampules to minimize the loss of Re from volatilization during melting at 1000 °C. The rhenium was found as Re(7+) in all of the glasses as observed by X-ray absorption near-edge structure. The solubility of Re in borosilicate glasses was determined to be ~3000 ppm (by mass) using inductively coupled plasma optical emission spectroscopy. At higher rhenium concentrations, additional rhenium was retained in the glasses as crystalline inclusions of alkali perrhenates detected with X-ray diffraction. Since (99)Tc concentrations in a glass waste form are predicted to be wastes, assuming Tc as Tc(7+) and similarities between Re(7+) and Tc(7+) behavior in this glass system.

  12. Effects of optical dopants and laser wavelength on atom probe tomography analyses of borosilicate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Xiaonan; Schreiber, Daniel K.; Neeway, James J.; Ryan, Joseph V.; Du, Jincheng

    2017-06-07

    Atom probe tomography (APT) is a novel analytical microscopy method that provides three dimensional elemental mapping with sub-nanometer spatial resolution and has only recently been applied to insulating glass and ceramic samples. In this paper, we have studied the influence of the optical absorption in glass samples on APT characterization by introducing different transition metal optical dopants to a model borosilicate nuclear waste glass (international simple glass). A systematic comparison is presented of the glass optical properties and the resulting APT data quality in terms of compositional accuracy and the mass spectra quality for two APT systems: one with a green laser (532 nm, LEAP 3000X HR) and one with a UV laser (355 nm, LEAP 4000X HR). These data were also compared to the study of a more complex borosilicate glass (SON68). The results show that the analysis data quality such as compositional accuracy and total ions collected, was clearly linked to optical absorption when using a green laser, while for the UV laser optical doping aided in improving data yield but did not have a significant effect on compositional accuracy. Comparisons of data between the LEAP systems suggest that the smaller laser spot size of the LEAP 4000X HR played a more critical role for optimum performance than the optical dopants themselves. The smaller spot size resulted in more accurate composition measurements due to a reduced background level independent of the material’s optical properties.

  13. Investigations on LM6 Metal Matrix Composite with borosilicate Glass Reinforcement for Aerospace applications

    Science.gov (United States)

    Rathnaraj, J. David; Sathish, S.

    2017-10-01

    The recycling of glass wastes from the industries and society holds a threat to the environment and leads to the need for new applications. While producing a metal matrix composite production cost is an important factor which decides the suitable application. So, while developing a new material with this low - cost has great importance in this competitive world. In this study, an metal-matrix composite fabricated from an aluminum alloy (LM6) and Borosilicate glass powder particles with % addition of 2.5%, 5%, 7.5%, and 10% were produced by liquid Processing (stir casting) technique. The variations in the mechanical properties like toughness, compressive strength, hardness, and tensile were examined. The microstructures of the fabricated metal matrix composite have been obtained by using Metallographic microscope. The addition of the borosilicate glass indicated an improved behavior in the hardness and toughness properties. The Rockwell hardness value of fabricated metal matrix composite increases with the increase in % of reinforcement. The compressive and tensile strength of the fabricated MMC increases until reinforcement reaches a maximum of 7.5%. The microstructure of the fabricated MMC shows that the reinforcements were homogeneously distributed in the fabricated metal matrix composite.

  14. Optical and structural investigation on sodium borosilicate glasses doped with Cr2O3

    Science.gov (United States)

    Ebrahimi, E.; Rezvani, M.

    2018-02-01

    In this work, Sodium borosilicate glasses with chemical composition of 60% SiO2-20% B2O3-20%Na2O doped with different contents of Cr2O3 were prepared by melting-quenching method. Physical, structural and optical properties of glasses were investigated by studying density and molar volume, Fourier Transform Infrared (FT-IR) Spectra and UV-visible absorption spectroscopy. The results showed an increase in density of glasses with the increase of Cr2O3 that can be due to addition of oxide with high molar mass. The optical absorption spectra of un-doped glass reveals UV absorption due to trace iron impurities with no visible band however Cr2O3 doped glasses shows absorption in visible range that are characteristic. Increasing of Cr3 + ions in the glassy microstructure of samples provides a semiconducting character to Sodium borosilicate glass by reducing the direct and indirect optical band gaps of glass samples from 3.79 to 2.59 (ev) and 3.36 to 2.09 (ev), respectively. These changes could be attributed to the role of Cr3 + ions as the network former which asserts improvement of semiconducting behavior in presence of Cr2O3.

  15. Understanding the structural drivers governing glass-water interactions in borosilicate based model bioactive glasses.

    Science.gov (United States)

    Stone-Weiss, Nicholas; Pierce, Eric M; Youngman, Randall E; Gulbiten, Ozgur; Smith, Nicholas J; Du, Jincheng; Goel, Ashutosh

    2018-01-01

    The past decade has witnessed a significant upsurge in the development of borate and borosilicate based resorbable bioactive glasses owing to their faster degradation rate in comparison to their silicate counterparts. However, due to our lack of understanding about the fundamental science governing the aqueous corrosion of these glasses, most of the borate/borosilicate based bioactive glasses reported in the literature have been designed by "trial-and-error" approach. With an ever-increasing demand for their application in treating a broad spectrum of non-skeletal health problems, it is becoming increasingly difficult to design advanced glass formulations using the same conventional approach. Therefore, a paradigm shift from the "trial-and-error" approach to "materials-by-design" approach is required to develop new-generations of bioactive glasses with controlled release of functional ions tailored for specific patients and disease states, whereby material functions and properties can be predicted from first principles. Realizing this goal, however, requires a thorough understanding of the complex sequence of reactions that control the dissolution kinetics of bioactive glasses and the structural drivers that govern them. While there is a considerable amount of literature published on chemical dissolution behavior and apatite-forming ability of potentially bioactive glasses, the majority of this literature has been produced on silicate glass chemistries using different experimental and measurement protocols. It follows that inter-comparison of different datasets reveals inconsistencies between experimental groups. There are also some major experimental challenges or choices that need to be carefully navigated to unearth the mechanisms governing the chemical degradation behavior and kinetics of boron-containing bioactive glasses, and to accurately determine the composition-structure-property relationships. In order to address these challenges, a simplified

  16. Effects of system size and cooling rate on the structure and properties of sodium borosilicate glasses from molecular dynamics simulations

    Science.gov (United States)

    Deng, Lu; Du, Jincheng

    2018-01-01

    Borosilicate glasses form an important glass forming system in both glass science and technologies. The structure and property changes of borosilicate glasses as a function of thermal history in terms of cooling rate during glass formation and simulation system sizes used in classical molecular dynamics (MD) simulation were investigated with recently developed composition dependent partial charge potentials. Short and medium range structural features such as boron coordination, Si and B Qn distributions, and ring size distributions were analyzed to elucidate the effects of cooling rate and simulation system size on these structure features and selected glass properties such as glass transition temperature, vibration density of states, and mechanical properties. Neutron structure factors, neutron broadened pair distribution functions, and vibrational density of states were calculated and compared with results from experiments as well as ab initio calculations to validate the structure models. The results clearly indicate that both cooling rate and system size play an important role on the structures of these glasses, mainly by affecting the 3B and 4B distributions and consequently properties of the glasses. It was also found that different structure features and properties converge at different sizes or cooling rates; thus convergence tests are needed in simulations of the borosilicate glasses depending on the targeted properties. The results also shed light on the complex thermal history dependence on structure and properties in borosilicate glasses and the protocols in MD simulations of these and other glass materials.

  17. A kinetic approach of sulphur behaviour in borosilicate glasses and melts: implications for sulphate incorporation in nuclear waste glasses

    Energy Technology Data Exchange (ETDEWEB)

    Lenoir, Marion [Service de Confinement des Dechets et Vitrification - Laboratoire d' Etudes de Base sur les Verres, CEA Valrho, Centre de Marcoule, 30207 Bagnols sur Ceze (France); Physique des Mineraux et des Magmas, UMR 7047 - CNRS, Institut de Physique du Globe de Paris, 7 place Jussieu, 75252 Paris Cedex 05 (France); Grandjean, Agnes [Service de Confinement des Dechets et Vitrification - Laboratoire d' Etudes de Base sur les Verres, CEA Valrho, Centre de Marcoule, 30207 Bagnols sur Ceze (France); Neuville, Daniel R. [Physique des Mineraux et des Magmas, UMR 7047 - CNRS, Institut de Physique du Globe de Paris, 7 place Jussieu, 75252 Paris Cedex 05 (France)

    2008-07-01

    The kinetics of sulphate decomposition in a borosilicate melt were studied using in situ Raman spectroscopy. This technique permits the quantification of the amount of sulphate dissolved in a borosilicate glass as a function of heating time by comparison with measurements obtained by microprobe WDS (Wavelength Dispersive Spectrometry). In order to quantify the content of sulphate obtained by Raman spectroscopy, the integrated intensity of the sulphate band at 985 cm{sup -1} was scaled to the sum of the integrated bands between 800 and 1200 cm{sup -1}, bands that are assigned to Q{sup n} silica units on the basis of previous literature. Viscosities of some borosilicate glasses are also presented here in order to study the kinetics of sulphate decomposition as a function of the viscosity of the melt. This underlines the importance of variations in viscosity depending on the composition of the melt and thus shows that viscosity is an important parameter governing the kinetics of decomposition of sulphate in borosilicate glasses. (authors)

  18. Comparison of SRP high-level waste disposal costs for borosilicate glass and crystalline ceramic waste forms

    International Nuclear Information System (INIS)

    McDonell, W.R.

    1982-04-01

    An evaluation of costs for the immobilization and repository disposal of SRP high-level wastes indicates that the borosilicate glass waste form is less costly than the crystalline ceramic waste form. The wastes were assumed immobilized as glass with 28% waste loading in 10,300 reference 24-in.-diameter canisters or as crystalline ceramic with 65% waste loading in either 3400 24-in.-diameter canisters or 5900 18-in.-diameter canisters. After an interim period of onsite storage, the canisters would be transported to the federal repository for burial. Total costs in undiscounted 1981 dollars of the waste disposal operations, excluding salt processing for which costs are not yet well defined, were about $2500 million for the borosilicate glass form in reference 24-in.-diameter canisters, compared to about $2900 million for the crystalline ceramic form in 24-in.-diameter canisters and about $3100 million for the crystalline ceramic form in 18-in.-diameter canisters. No large differences in salt processing costs for the borosilicate glass and crystalline ceramic forms are expected. Discounting to present values, because of a projected 2-year delay in startup of the DWPF for the crystalline ceramic form, preserved the overall cost advantage of the borosilicate glass form. The waste immobilization operations for the glass form were much less costly than for the crystalline ceramic form. The waste disposal operations, in contrast, were less costly for the crystalline ceramic form, due to fewer canisters requiring disposal; however, this advantage was not sufficient to offset the higher development and processing costs of the crystalline ceramic form. Changes in proposed Nuclear Regulatory Commission regulations to permit lower cost repository packages for defense high-level wastes would decrease the waste disposal costs of the more numerous borosilicate glass forms relative to the crystalline ceramic forms

  19. Electrical characterization of strontium titanate borosilicate glass ceramics system with bismuth oxide addition using impedance spectroscopy

    International Nuclear Information System (INIS)

    Thakur, O.P.; Kumar, Devendra; Parkash, Om; Pandey, Lakshman

    2003-01-01

    The ac electrical data, measured in the frequency range 0.1 kHz-1 MHz, were used to study the electrical response of strontium titanate borosilicate glass ceramic system with bismuth oxide addition. Complex plane plots from these electrical data for various glass ceramic samples reveal contributions from simultaneously operating polarization mechanisms to overall dielectric behavior. The complex modulus (M * ) representation of electrical data for various glass ceramic samples were found to be more informative. Equivalent circuit models, which represent the electrical behavior of glass ceramic samples, were determined using complex non-linear least square (CNLS) fitting. An attempt has been made to understand the dielectric behavior of various glass ceramics in terms of contributions arising from different polarization processes occurring at glassy matrix, crystalline phases, glass to crystal interface region and blocking electrodes. Glass ceramics containing SrTiO 3 and TiO 2 (rutile) phases show thermally stable dielectric behavior

  20. Effect of annealing on the composition of PECVD borosilicate and borophosphosilicate glasses

    Science.gov (United States)

    Osório, S. P. A.; Montero, I.; Perrière, J.; Martinez-Duart, J. M.

    1993-06-01

    Borosilicate, B xSiO z (BSG), and borophosphosilicate, B xP ySiO z (BPSG) glasses, for applications as intermetal dielectrics in VLSI technology were deposited by plasma enhanced chemical vapor deposition on silicon substrates. Quantitative infrared spectroscopy (IR), Rutherford backscattering spectroscopy (RBS), nuclear reaction analysis (NRA) and X-ray energy dispersion (EDX) were used to obtain the composition of the films. After annealing at temperatures in the range 200 to 900°C under a nitrogen ambient, the concentration of phosphorus and boron in the deposited films is analyzed. It is found that the phosphorus concentration is independent of the annealing temperature. However, the boron concentration decreases with the annealing temperature in both types of glasses. This effect can be attributed to the influence of the concentration of the P-O bonds in the phosphorus doped films, and also to the morphology and hygroscopicity of the films.

  1. Development of Composite Materials Under Ecological Aspects as Recycling Concept For Borosilicate Glass Containing Iron Slags

    International Nuclear Information System (INIS)

    Khalil, T.K.; Bossert, J.; Aly, H.F.; Bossert, J.

    1999-01-01

    Composite concept in materials science can be conveniently applied in the waste treatment technology to construct specific t ailor made c omposite materials, in which at least one of the phases is built by the waste material. In this work the applicability of this concept for the fixation and recycling of slags wastes is done, whereby different mixtures of blast furnace slags are mixed with two different borosilicate glasses, which serve as matrix material. Thermal behaviour of the produced compacts were studied. Both melting and powder technology are applied for the fabrication of dense products. The microstructure of sintered samples is investigated by electron microscopy. The mechanical properties such as hardness and fracture toughness are determined by a Vickers technique. An improvement of the fracture toughness of more than 50% over the value for the original glass VG 98 is achieved by slag addition

  2. Determination of iron redox ratio in borosilicate glasses and melts from Raman spectra

    Energy Technology Data Exchange (ETDEWEB)

    Cochain, B. [SCDV-Laboratoire d' Etudes de Base sur les Verres, CEA Valrho, Centre de Marcoule, 30207 Bagnols-sur-ceze (France); Physique des Mineraux et des Magmas, CNRS-IPGP, 4 place Jussieu, 75252 Paris Cedex05 (France); Neuville, D.R.; Richet, P. [Physique des Mineraux et des Magmas, CNRS-IPGP, 4 place Jussieu, 75252 Paris Cedex05 (France); Henderson, G.S. [Dept of Geology, University of Toronto, 22 Russell Street, Toronto (Canada); Pinet, O. [SCDV-Laboratoire d' Etudes de Base sur les Verres, CEA Valrho, Centre de Marcoule, 30207 Bagnols-sur-ceze (France)

    2008-07-01

    A method is presented to determine the redox ratio of iron in borosilicate glasses and melts relevant to nuclear waste storage from an analysis of Raman spectra recorded at room or high temperature. The basis of this method is the strong variation of the spectral feature observed between 800 and 1200 cm{sup -1}, in which it is possible to assign a band to vibrational modes involving ferric iron in tetrahedral coordination whose intensity increases with iron content and iron oxidation. After baseline correction and normalization, fits to the Raman spectra made with Gaussian bands enable us to determine the proportion of ferric iron provided the redox ratio is known independently for at least two redox states for a given glass composition. This method is particularly useful for in situ determinations of the kinetics and mechanisms of redox reactions. (authors)

  3. Magnetic Glass Ceramics by Sintering of Borosilicate Glass and Inorganic Waste

    Directory of Open Access Journals (Sweden)

    Inès M. M. M. Ponsot

    2014-07-01

    Full Text Available Ceramics and glass ceramics based on industrial waste have been widely recognized as competitive products for building applications; however, there is a great potential for such materials with novel functionalities. In this paper, we discuss the development of magnetic sintered glass ceramics based on two iron-rich slags, coming from non-ferrous metallurgy and recycled borosilicate glass. The substantial viscous flow of the glass led to dense products for rapid treatments at relatively low temperatures (900–1000 °C, whereas glass/slag interactions resulted in the formation of magnetite crystals, providing ferrimagnetism. Such behavior could be exploited for applying the obtained glass ceramics as induction heating plates, according to preliminary tests (showing the rapid heating of selected samples, even above 200 °C. The chemical durability and safety of the obtained glass ceramics were assessed by both leaching tests and cytotoxicity tests.

  4. ARTICLES: Polarization effects in birefringent fiber waveguides with an elliptic borosilicate cladding

    Science.gov (United States)

    Grigor'yants, V. V.; Zalogin, A. N.; Ivanov, G. A.; Isaev, Victor A.; Kozel, S. M.; Listvin, V. N.; Chamorovskiĭ, Yu K.

    1986-10-01

    Single-mode fiber waveguides with an elliptic borosilicate cladding were developed and their polarization characteristics were studied. It was found that the mode birefringence was independent of the radiation frequency and varied linearly with the fiber waveguide temperature. The length of the beats was ~10 mm at λ = 0.85μ, whereas the dispersion of the polarization modes was 300 psec/km. The losses were 5-10 dB/km at λ = 0.85μ and the mode coupling parameter was h = 2×10-4m-1. A study was made of the possibility of using single-mode fiber waveguides for the depolarization of nonmonochromatic radiation and also as tunable delay lines.

  5. Polarization effects in birefringent fiber-optic waveguides with an elliptical borosilicate cladding

    Science.gov (United States)

    Grigoriants, V. V.; Zalogin, A. N.; Ivanov, G. A.; Isaev, V. A.; Kozel, S. M.

    1986-10-01

    Single-mode fiber-optic waveguides (SFW) with an elliptical borosilicate cladding are developed and their polarization characteristics are studied. It is shown that their mode birefringence, while independent of the radiation frequency, depends linearly on the SFW temperature. The beat length is about 10 mm at a wavelength of 0.85 micron and the dispersion of the polarization modes is about 300 ps/km. The losses amount to 5-10 dB/km at 0.85 micron and the mode coupling parameter is 0.0002/m. Consideration is given to the possibility of using SFW for the depolarization of nonmonochromatic radiation and as tunable delay lines.

  6. Aqueous corrosion of borosilicate glasses: experiments, modeling and Monte-Carlo simulations

    International Nuclear Information System (INIS)

    Ledieu, A.

    2004-10-01

    This work is concerned with the corrosion of borosilicate glasses with variable oxide contents. The originality of this study is the complementary use of experiments and numerical simulations. This study is expected to contribute to a better understanding of the corrosion of nuclear waste confinement glasses. First, the corrosion of glasses containing only silicon, boron and sodium oxides has been studied. The kinetics of leaching show that the rate of leaching and the final degree of corrosion sharply depend on the boron content through a percolation mechanism. For some glass contents and some conditions of leaching, the layer which appears at the glass surface stops the release of soluble species (boron and sodium). This altered layer (also called the gel layer) has been characterized with nuclear magnetic resonance (NMR) and small angle X-ray scattering (SAXS) techniques. Second, additional elements have been included in the glass composition. It appears that calcium, zirconium or aluminum oxides strongly modify the final degree of corrosion so that the percolation properties of the boron sub-network is no more a sufficient explanation to account for the behavior of these glasses. Meanwhile, we have developed a theoretical model, based on the dissolution and the reprecipitation of the silicon. Kinetic Monte Carlo simulations have been used in order to test several concepts such as the boron percolation, the local reactivity of weakly soluble elements and the restructuring of the gel layer. This model has been fully validated by comparison with the results on the three oxide glasses. Then, it has been used as a comprehensive tool to investigate the paradoxical behavior of the aluminum and zirconium glasses: although these elements slow down the corrosion kinetics, they lead to a deeper final degree of corrosion. The main contribution of this work is that the final degree of corrosion of borosilicate glasses results from the competition of two opposite mechanisms

  7. Intrinsic dosimetry. Properties and mechanisms of thermoluminescence in commercial borosilicate glass

    Energy Technology Data Exchange (ETDEWEB)

    Clark, Richard A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2012-10-01

    Intrinsic dosimetry is the method of measuring total absorbed dose received by the walls of a container holding radioactive material. By considering the total absorbed dose received by a container in tandem with the physical characteristics of the radioactive material housed within that container, this method has the potential to provide enhanced pathway information regarding the history of the container and its radioactive contents. The latest in a series of experiments designed to validate and demonstrate this newly developed tool are reported. Thermoluminescence (TL) dosimetry was used to measure dose effects on raw stock borosilicate container glass up to 70 days after gamma ray, x-ray, beta particle or ultraviolet irradiations at doses from 0.15 to 20 Gy. The TL glow curve when irradiated with 60Co was separated into five peaks: two relatively unstable peaks centered near 120 and 165°C, and three relatively stable peaks centered near 225, 285, and 360°C. Depending on the borosilicate glass source, the minimum measurable dose using this technique is 0.15-0.5 Gy, which is roughly equivalent to a 24 hr irradiation at 1 cm from a 50-165 ng source of 60Co. Differences in TL glow curve shape and intensity were observed for the glasses from different geographical origins. These differences can be explained by changes in the intensities of the five peaks. Electron paramagnetic resonance (EPR) and multivariate statistical methods were used to relate the TL intensity and peaks to electron/hole traps and compositional variations.

  8. Comparison of radiation and quenching rate effects on the structure of a sodium borosilicate glass

    International Nuclear Information System (INIS)

    Peuget, Sylvain; Maugeri, Emilio-Andrea; Mendoza, Clement; Fares, Toby; Bouty, Olivier; Jegou, Christophe; Charpentier, Thibault; Moskura, Melanie

    2013-01-01

    The effects of quenching rate and irradiation on the structure of a sodium borosilicate glass were compared using 29 Si, 11 B, and 23 Na nuclear magnetic resonance and Raman spectroscopy. Quenching rate ranging from 0.1 to 3 * 10 4 K min -1 was studied. Various irradiation conditions were performed, i.e. gold-ion irradiation in a multi-energy mode (from 1 to 6.75 MeV), and Kr and Xe ion irradiations with energy of 74 and 92 MeV, respectively. In pile irradiation with thermal neutron flux was performed as well, to study the effect of alpha radiation from the nuclear reaction 10 B(n,α) 7 Li. Both irradiation and high quenching rate induce similar local order modification of the glass structure, mainly a decrease of the mean boron coordination and an increase of Q 3 units. Nevertheless, the variations observed under irradiation are more pronounced than the ones induced by the quenching rate. Moreover, some important modifications of the glass medium range order, i.e. the emergence of the D2 band associated to three members silica rings and a modification of the Si-O-Si angle distribution were only noticed after irradiation. These results suggest that the irradiated structure is certainly not exactly the one obtained by a rapidly quenched equilibrated melt, but rather a more disordered structure that was weakly relaxed during the very rapid quenching phase following the energy deposition step. Raman spectroscopy showed a similar irradiated structure whereas the glass evolutions were controlled by the electronic energy loss in the ion track formation regime for Kr-ion irradiation or by the nuclear energy loss for Au and OSIRIS irradiation. The similar irradiated structure despite different irradiation routes, suggests that the final structural state of this sodium borosilicate glass is mainly controlled by the glass reconstruction after the energy deposition step. (authors)

  9. Water leaching of borosilicate glasses: experiments, modeling and Monte Carlo simulations

    International Nuclear Information System (INIS)

    Ledieu, A.

    2004-10-01

    This work is concerned with the corrosion of borosilicate glasses with variable oxide contents. The originality of this study is the complementary use of experiments and numerical simulations. This study is expected to contribute to a better understanding of the corrosion of nuclear waste confinement glasses. First, the corrosion of glasses containing only silicon, boron and sodium oxides has been studied. The kinetics of leaching show that the rate of leaching and the final degree of corrosion sharply depend on the boron content through a percolation mechanism. For some glass contents and some conditions of leaching, the layer which appears at the glass surface stops the release of soluble species (boron and sodium). This altered layer (also called the gel layer) has been characterized with nuclear magnetic resonance (NMR) and small angle X-ray scattering (SAXS) techniques. Second, additional elements have been included in the glass composition. It appears that calcium, zirconium or aluminum oxides strongly modify the final degree of corrosion so that the percolation properties of the boron sub-network is no more a sufficient explanation to account for the behavior of these glasses. Meanwhile, we have developed a theoretical model, based on the dissolution and the reprecipitation of the silicon. Kinetic Monte Carlo simulations have been used in order to test several concepts such as the boron percolation, the local reactivity of weakly soluble elements and the restructuring of the gel layer. This model has been fully validated by comparison with the results on the three oxide glasses. Then, it has been used as a comprehensive tool to investigate the paradoxical behavior of the aluminum and zirconium glasses: although these elements slow down the corrosion kinetics, they lead to a deeper final degree of corrosion. The main contribution of this work is that the final degree of corrosion of borosilicate glasses results from the competition of two opposite mechanisms

  10. Fabrication of Silicon Nitride Dental Core Ceramics with Borosilicate Veneering material

    Energy Technology Data Exchange (ETDEWEB)

    Wananuruksawong, R; Jinawath, S; Wasanapiarnpong, T [Research Unit of Advanced Ceramic, Department of Materials Science, Faculty of Science, Chulalongkorn University, Bangkok (Thailand); Padipatvuthikul, P, E-mail: raayaa_chula@hotmail.com [Faculty of Dentistry, Srinakharinwirot University, Bangkok (Thailand)

    2011-10-29

    Silicon nitride (Si{sub 3}N{sub 4}) ceramic is a great candidate for clinical applications due to its high fracture toughness, strength, hardness and bio-inertness. This study has focused on the Si{sub 3}N{sub 4} ceramic as a dental core material. The white Si{sub 3}N{sub 4} was prepared by pressureless sintering at relative low sintering temperature of 1650 deg. C in nitrogen atmosphere. The coefficient of thermal expansion (CTE) of Si{sub 3}N{sub 4} ceramic is lower than that of Zirconia and Alumina ceramic which are popular in this field. The borosilicate glass veneering was employed due to its compatibility in thermal expansion. The sintered Si{sub 3}N{sub 4} specimens represented the synthetic dental core were paintbrush coated by a veneer paste composed of borosilicate glass powder (<150 micrometer, Pyrex) with 5 wt% of zirconia powder (3 wt% Y{sub 2}O{sub 3} - partial stabilized zirconia) and 30 wt% of polyvinyl alcohol (5 wt% solution). After coating the veneer on the Si{sub 3}N{sub 4} specimens, the firing was performed in electric tube furnace between 1000-1200 deg. C. The veneered specimens fired at 1100 deg. C for 15 mins show good bonding, smooth and glossy without defect and crazing. The veneer has thermal expansion coefficient as 3.98x10{sup -6} deg. C{sup -1}, rather white and semi opaque, due to zirconia addition, the Vickers hardness as 4.0 GPa which is closely to the human teeth.

  11. Chemical corrosion of highly radioactive borosilicate nuclear waste glass under simulated repository conditions

    International Nuclear Information System (INIS)

    Werme, L.; Bjoerner, I.K.; Bart, G.; Zwicky, H.U.; Grambow, B.; Lutze, W.; Ewing, R.C.; Magrabi, C.

    1990-01-01

    This review summarizes the results of the joint Japanese (Central Research Institute of Electric Power Industry, CRIEPI, Tokyo), Swiss (National Cooperative for the Storage of Radioactive Waste, NAGRA, Baden), Swedish (Swedish Nuclear Fuel and Waste Management Company, SKB, Stockholm) international 'JSS' project on the determination of the chemical durability of the French nuclear waste borosilicate glass, which was completed in 1988. Radioactive and non-radioactive glass specimens were investigated. A data base was created with results from glass corrosion tests performed with different water compositions, pH values, temperatures, sample surface areas (S), solution volumes (V), and flow rates. Glass corrosion tests were performed with and without bentonite and/or steel corrosion products present. Variation of the glass composition was taken into account by including the borosilicate glass 'MW' in the investigations, formulated by British Nuclear Fuels, plc. An understanding was achieved of the glass corrosion process in general, and of the performance of the French glass under various potential disposal conditions in particular. A special effort was made to establish a corrosion data base, using high S/V ratios in the experiments in order to understand the glass durability in the long term. A computer program, GLASSOL, was developed, based on a dissolution-precipitation model, to calculate the glass water reaction. Fair agreement between observations and the model calculations was achieved. Use of a constant (time-independent) long-term rate was justified by observations on naturally altered basaltic glasses of great age, which were compatible with what was inferred from experiments with nuclear waste glasses in the laboratory. A fractured glass block would not be altered within 10 000 years at 90 degree C (flow rate <100 L/year)

  12. Preparation and characterization of an improved borosilicate glass for the solidification of high level radioactive fission product solutions (HLW). Pt. 2

    International Nuclear Information System (INIS)

    Kahl, L.; Ruiz-Lopez, M.C.; Saidl, J.; Dippel, T.

    1982-04-01

    In the 'Institut fuer Nuklare Entsorgungstechnik' the borosilicate glass VG 98/12 has been developed for the solidification of the high level radioactive waste (HLW). This borosilicate glass can be used in a direct heated ceramic melter and forms together with the HLW the borosilicate glass product GP 98/12. This borosilicate glass product has been examined in detail both in liquid and solid state. The elements contained in the HLW can be incorporated without problems. Only in a few exceptions the concentration must be kept below certain limits to exclude the formation of a second phase ('yellow phase') by separation. No spontaneous crystallization and no crystallization over a long time could be observed as long as the temperature of the borosilicate glass product is kept below its transformation area. Simulating accidental conditions in the final storage, samples had been leached at temperatures up to 200 0 C and pressures up to 130 bar with saturated rock salt brine and saturated quinary salt brine. The leaching process seems to be stopped by the formed 'leached layer' on the surface of the borosilicate glass product after a limited leaching time. Detailed investigations have been started to explain this phenomenon. (orig.) [de

  13. High-level waste glass compendium; what it tells us concerning the durability of borosilicate waste glass

    International Nuclear Information System (INIS)

    Cunnane, J.C.; Allison, J.

    1993-01-01

    Facilities for vitrification of high-level nuclear waste in the United States are scheduled for startup in the next few years. It is, therefore, appropriate to examine the current scientific basis for understanding the corrosion of high-level waste borosilicate glass for the range of service conditions to which the glass products from these facilities may be exposed. To this end, a document has been prepared which compiles worldwide information on borosilicate waste glass corrosion. Based on the content of this document, the acceptability of canistered waste glass for geological disposal is addressed. Waste glass corrosion in a geologic repository may be due to groundwater and/or water vapor contact. The important processes that determine the glass corrosion kinetics under these conditions are discussed based on experimental evidence from laboratory testing. Testing data together with understanding of the long-term corrosion kinetics are used to estimate radionuclide release rates. These rates are discussed in terms of regulatory performance standards

  14. The Effect of Caramelization and Carbonization Temperatures toward Structural Properties of Mesoporous Carbon from Fructose with Zinc Borosilicate Activator

    OpenAIRE

    Setianingsih, Tutik; Kartini, Indriana; Arryanto, Yateman

    2014-01-01

    Mesoporous carbon was prepared from fructose using zinc borosilicate (ZBS) activator. The synthesis involves caramelization and carbonization processes. The effect of both process temperature toward porosity and functional group of carbon surface are investigated in this research. The caramelization was conducted hydrothermally at 85 and 100 °C, followed by thermally 130 °C. The carbonization was conducted at various temperatures (450–750 °C). The carbon-ZBS composite were washed by using HF ...

  15. 4.2. The kinetics of nitric acid decomposition of calcined borosilicate raw material of Ak-Arkhar Deposit

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.; Kurbonov, A.S.; Mamatov, E.D.

    2015-01-01

    Present article is devoted to kinetics of nitric acid decomposition of calcined borosilicate raw material of Ak-Arkhar Deposit. The dependence of nitric acid decomposition of calcined boric raw material for extraction of boron oxide on temperature (20-100 deg C) and process duration (15-60 minutes) was defined. It was defined that at temperature increasing the extraction rate of boron oxide increases from 20.8 to 78.6%.

  16. Entrapment of 137Cs vapour generated during vitrification and casting of cesium borosilicate glass by inorganic materials

    International Nuclear Information System (INIS)

    Ram, Ramu; Gandhi, Shyamala; Dash, A.; Varma, R.N.

    2003-01-01

    Efficiency of different inorganic materials like zirconium antimonate (ZrA), ammonium molybdophosphate (AMP), synthetic zeolites, activated charcoal, glass wool etc, towards the entrapment of 137 Cs vapour escaping during vitrification and casting of cesium borosilicate glass required for the preparation of 137 Cs sources for medical and industrial applications have been determined. The recovery of entrapped cesium using dilute acids for subsequent recycling has also been explored. (author)

  17. Barium borosilicate glass - a potential matrix for immobilization of sulfate bearing high-level radioactive liquid waste

    International Nuclear Information System (INIS)

    Kaushik, C.P.; Mishra, R.K.; Sengupta, P.; Kumar, Amar; Das, D.; Kale, G.B.; Raj, Kanwar

    2006-01-01

    Borosilicate glass formulations adopted worldwide for immobilization of high-level radioactive liquid waste (HLW) is not suitable for sulphate bearing HLW, because of its low solubility in such glass. A suitable glass matrix based on barium borosilicate has been developed for immobilization of sulphate bearing HLW. Various compositions based on different glass formulations were made to examine compatibility with waste oxide with around 10 wt% sulfate content. The vitrified waste product obtained from barium borosilicate glass matrix was extensively evaluated for its characteristic properties like homogeneity, chemical durability, glass transition temperature, thermal conductivity, impact strength, etc. using appropriate techniques. Process parameters like melt viscosity and pour temperature were also determined. It is found that SB-44 glass composition (SiO 2 : 30.5 wt%, B 2 O 3 : 20.0 wt%, Na 2 O: 9.5 wt% and BaO: 19.0 wt%) can be safely loaded with 21 wt% waste oxide without any phase separation. The other product qualities of SB-44 waste glass are also found to be on a par with internationally adopted waste glass matrices. This formulation has been successfully implemented in plant scale

  18. Structure and chemical durability of barium borosilicate glass–ceramics containing zirconolite and titanite crystalline phases

    International Nuclear Information System (INIS)

    Li, Huidong; Wu, Lang; Xu, Dong; Wang, Xin; Teng, Yuancheng; Li, Yuxiang

    2015-01-01

    In order to increase the solubility of actinides in the glass matrix, the effects of CaO, TiO 2 , and ZrSiO 4 addition (abbreviated as CTZ, in the mole ratio of 2:2:1) on crystalline phases, microstructure, and chemical durability of barium borosilicate glass–ceramics were investigated. The results show that the samples possess both zirconolite-2M and titanite phase when the CTZ content is greater than or equal to 45 wt.%. For the glass–ceramics with 45 wt.% CTZ (CTZ-45), only zirconolite-2M phase is observed after annealing at 680–740 °C for 2 h. The CTZ-45 possess zirconolite-2M and titanite phases after annealing at 700 °C first, and then annealing at 900–1050 °C for 2 h. Furthermore, the zirconolite-2M and titanite grains show a strip and brick shape, respectively. The CTZ-45 annealing at 950 °C shows the lower normalized leaching rates of B, Na and Nd when compared to that of CTZ-0 and CTZ-55. - Highlights: • CaO, TiO 2 , ZrSiO 4 (CTZ) as nucleating agents were added to barium borosilicate glass. • The samples with 45–55 wt% CTZ possess CaZrTi 2 O 7 -2M and CaTiSiO 5 crystalline phases. • CTZ-45 (45wt% CTZ) possesses only CaZrTi 2 O 7 -2M phase after annealing at 680–740 °C. • CTZ-45 possesses CaZrTi 2 O 7 -2M and CaTiSiO 5 phases after annealing at 900–1050 °C. • CTZ-45 annealing at 950 °C shows the lower leaching rates of B, Na and Nd than CTZ-0 and CTZ-55.

  19. There Is Still Room for Improvement: Presentation of a Neutral Borosilicate Glass with Improved Chemical Stability for Parenteral Packaging.

    Science.gov (United States)

    Boltres, Bettine; Tratzky, Stephan; Kass, Christof; Eichholz, Rainer; Naß, Peter

    2016-01-01

    For pharmaceutical parenteral packaging the glass compositions have always been either Type I borosilicate or Type III soda-lime glass. As both the compositions and certain chemical and physical properties are mandated by international standards, there has not been room for any changes. However, by applying only minor adjustments, a borosilicate glass was developed that showed improved chemical stability. The chemical composition is still in the range of currently used borosilicate glasses, which makes it a Type I glass according to all current pharmacopeia. A study was performed on glass vials comparing the new glass with the standard FIOLAX(®) and two other publicly available glasses. In an extraction study with water at 121 °C the new glass showed the highest chemical stability with the lowest amount of extractables. In an accelerated ageing study, which was done with water, phosphate, and carbonate buffer at 40 °C for 12 months, the new glass also proved to have the lowest amount of leachables. In this article the new glass and the results from the studies are presented, showing the reader how much of an effect can be attained with only minor adjustments if the scientific fundamentals are clear. The pharmaceutical market has been quite constant and risk-oriented due to the high impact on the safety of the patient. As any change necessitates a complicated change process, this has, in consequence, lead the industry to resist changing the parenteral primary packaging material for decades. The main glasses have either been Type I borosilicate or Type III soda-lime glass. On the other hand, a combination of improved inspection systems and the development of more sensitive biologically based drugs has elevated the standards for parental packaging materials. For example, the measurement of extractables and leachables from the packaging material steadily came into focus. In this article, a new glass is presented that still belongs to the group of Type I borosilicate

  20. Influence of zeolite precipitation on borosilicate glass alteration under hyperalkaline conditions

    Science.gov (United States)

    Mercado-Depierre, S.; Fournier, M.; Gin, S.; Angeli, F.

    2017-08-01

    This study enables a better understanding of how nucleation-growth of zeolites affects glass dissolution kinetics in hyperalkaline solutions characteristic of cement waters. A 20-oxide borosilicate glass, an inactive surrogate of a typical intermediate level waste glass, was altered in static mode at 50 °C in a hyperalkaline solution rich in Na+, K+ and Ca2+ and at an initial pH50°C of 12.6. Experiments were performed at four glass-surface-area-to-solution-volume (S/V) ratios to investigate various reaction progresses. Two types of glass alteration kinetics were obtained: (i) at low S/V, a sharp alteration resumption occurred after a rate drop regime, (ii) at high S/V, a high dissolution rate was maintained throughout the test duration with a slight progressive slow-down. In all the experiments, zeolites precipitated but the time taken to form stable zeolite nuclei varied dramatically depending on the S/V. Resulting changes in pH affected zeolite composition, morphology, solubility and growth rate. A change in a critical parameter such as S/V affected all the processes controlling glass dissolution.

  1. Processing and optical characterization of lead calcium titanate borosilicate glass doped with germanium

    Science.gov (United States)

    Gautam, C. R.; Das, Sangeeta; Gautam, S. S.; Madheshiya, Abhishek; Singh, Anod Kumar

    2018-04-01

    In this study, various compositions of lead calcium titanate borosilicate glass doped with a fixed amount of germanium were synthesized using the rapid melt quench technique. The amorphous nature of the synthesized glass was confirmed by X-ray diffraction and scanning electron microscopy analyses. The structural and optical properties were deduced using Raman, Fourier transform infrared (FTIR), and ultraviolet-visible (UV-Vis) spectroscopy. FTIR spectroscopy confirmed the presence of borate groups in triangular and tetrahedral coordination. Infrared and Raman analyses detected the vibrational bonds of Gesbnd Osbnd Ge, Bsbnd Osbnd Ge, Sisbnd Osbnd Ge, Sisbnd Osbnd Si, and Pbsbnd Osbnd Ge. The energy band gaps were evaluated for the prepared glass samples based on Tauc plots of the UV-Vis spectra. The calculated values of the optical band gap decreased from 2.91 to 2.85 eV as the PbO content increased from x = 0.0 to x = 0.7. Furthermore, the Urbach energy was studied based on the UV-Vis results to confirm the disordered structure of the glass. The calculated densities of the glass samples (1.5835 g/cm3 to 3.9184 g/cm3) increased as the concentration of PbO increased, whereas they decreased with the molar volume.

  2. Smoothing of ultrasonically drilled holes in borosilicate glass by wet chemical etching

    Science.gov (United States)

    Diepold, T.; Obermeier, E.

    1996-03-01

    Besides silicon various types of glass play an important role in microsystem technology. One requirement of the glasses is that they have to be microstructurable. In many applications for microsensors and microstructures the glass must be suitable for anodic bonding. Usually borosilicate glass (e.g. Corning Pyrex code 7740 glass) is used, which has a thermal expansion coefficient that is almost equal to the thermal expansion coefficient of silicon and which has the necessary electrical conductivity at the temperature at which the bonding process occurs. For many applications, e.g., microfluidic systems, it is necessary to have fluids flown through ultrasonically drilled holes in the Pyrex glass to the silicon chip. The main objective of the investigation was to obtain smooth walls of ultrasonically drilled holes because every contamination influences the performance of the microsystem. In this paper the ultrasonic drilling method is compared with two other procedures for machining holes (sand blasting and laser machining). Other ways of structuring glass have been presented previously. A process was developed to smooth the walls of the drilled holes with different concentrations of hydrofluoric acid.

  3. Investigation of gamma radiation induced changes in local structure of borosilicate glass by TDPAC and EXAFS

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Ashwani, E-mail: kashwani@barc.gov.in [Bhabha Atomic Research Centre, Radioanalytical Chemistry Division (India); Nayak, C.; Rajput, P. [Bhabha Atomic Research Centre, Atomic and Molecular Physics Division (India); Mishra, R. K. [Bhabha Atomic Research Centre, Waste Management Division (India); Bhattacharyya, D. [Bhabha Atomic Research Centre, Atomic and Molecular Physics Division (India); Kaushik, C. P. [Bhabha Atomic Research Centre, Waste Management Division (India); Tomar, B. S. [Bhabha Atomic Research Centre, Radioanalytical Chemistry Division (India)

    2016-12-15

    Gamma radiation induced changes in local structure around the probe atom (Hafnium) were investigated in sodium barium borosilicate (NBS) glass, used for immobilization of high level liquid waste generated from the reprocessing plant at Trombay, Mumbai. The (NBS) glass was doped with {sup 181}Hf as a probe for time differential perturbed angular correlation (TDPAC) spectroscopy studies, while for studies using extended X-ray absorption fine structure (EXAFS) spectroscopy, the same was doped with 0.5 and 2 % (mole %) hafnium oxide. The irradiated as well as un-irradiated glass samples were studied by TDPAC and EXAFS techniques to obtain information about the changes (if any) around the probe atom due to gamma irradiation. TDPAC spectra of unirradiated and irradiated glasses were similar and reminescent of amorphous materials, indicating negligible effect of gamma radiation on the microstructure around Hafnium probe atom, though the quaqdrupole interaction frequency (ω{sub Q}) and asymmetry parameter (η) did show a marginal decrease in the irradiated glass compared to that in the unirradiated glass. EXAFS measurements showed a slight decrease in the Hf-O bond distance upon gamma irradiation of Hf doped NBS glass indicating densification of the glass matrix, while the cordination number around hafnium remains unchanged.

  4. Volatilization from borosilicate glass melts of simulated Savannah River Plant waste

    International Nuclear Information System (INIS)

    Wilds, G.W.

    1978-01-01

    Laboratory scale studies determined the rates at which the semivolatile components sodium, boron, lithium, cesium, and ruthenium volatilized from borosilicate glass melts that contained simulated Savannah River Plant waste sludge. Sodium and boric oxides volatilize as the thermally stable compound sodium metaborate, and accounted for approx. 90% of the semivolatiles that evolved. The amounts of semivolatiles that evolved increased linearly with the logarithm of the sodium content of the glass-forming mixture. Cesium volatility was slightly suppressed when titanium dioxide was added to the melt, but was unaffected when cesium was added to the melt as a cesium-loaded zeolite rather than as a cesium carbonate solution. Volatility of ruthenium was not suppressed when the glass melt was blanketed with a nonoxidizing atmosphere. Trace quantities of mercury were removed from vapor streams by adsorption onto a silver-exchanged zeolite. A bed containing silver in the ionic state removed more than 99.9% of the mercury and had a high chemisorption capacity. Beds of lead-, copper-, and copper sulfide-exchanged zeolite-X and also an unexchanged zeolite-X were tested. None of these latter beds had high removal efficiency and high chemisorption capacity

  5. High-level waste borosilicate glass: A compendium of corrosion characteristics. Volume 2

    International Nuclear Information System (INIS)

    Cunnane, J.C.

    1994-03-01

    The objective of this document is to summarize scientific information pertinent to evaluating the extent to which high-level waste borosilicate glass corrosion and the associated radionuclide release processes are understood for the range of environmental conditions to which waste glass may be exposed in service. Alteration processes occurring within the bulk of the glass (e.g., devitrification and radiation-induced changes) are discussed insofar as they affect glass corrosion.This document is organized into three volumes. Volumes I and II represent a tiered set of information intended for somewhat different audiences. Volume I is intended to provide an overview of waste glass corrosion, and Volume 11 is intended to provide additional experimental details on experimental factors that influence waste glass corrosion. Volume III contains a bibliography of glass corrosion studies, including studies that are not cited in Volumes I and II. Volume I is intended for managers, decision makers, and modelers, the combined set of Volumes I, II, and III is intended for scientists and engineers working in the field of high-level waste

  6. Deformation mechanisms during nanoindentation of sodium borosilicate glasses of nuclear interest

    Energy Technology Data Exchange (ETDEWEB)

    Kilymis, D. A.; Delaye, J.-M., E-mail: jean-marc.delaye@cea.fr [CEA Marcoule, DEN/DTCD, Service d’Etude et Comportement des Matériaux de Conditionnement, BP17171 30207 Bagnols-sur-Cèze Cedex (France)

    2014-07-07

    In this paper we analyze results of Molecular Dynamics simulations of Vickers nanoindentation, performed for sodium borosilicate glasses of interest in the nuclear industry. Three glasses have been studied in their pristine form, as well as a disordered one that is analogous to the real irradiated glass. We focused in the behavior of the glass during the nanoindentation in order to reveal the mechanisms of deformation and how they are affected by microstructural characteristics. Results have shown a strong dependence on the SiO{sub 2} content of the glass, which promotes densification due to the open structure of SiO{sub 4} tetrahedra and also due to the strength of Si-O bonds. Densification for the glasses is primarily expressed by the relative decrease of the Si-O-Si and Si-O-B angles, indicating rotation of the structural units and decrease of free volume. The increase of alkali content on the other hand results to higher plasticity of the matrix and increased shear flow. The most important effect on the deformation mechanism of the disordered glasses is that of the highly depolymerized network that will also induce shear flow and, in combination with the increased free volume, will result in the decreased hardness of these glasses, as has been previously observed.

  7. Formation and growth of semiconductor PbTe nanocrystals in a borosilicate glass matrix

    International Nuclear Information System (INIS)

    Craievich, A.F.; Alves, O.L.; Barbosa, L.C.

    1997-01-01

    Pb- and Te-doped borosilicate glasses are transformed by appropriate heat treatment into a composite material consisting of a vitreous matrix in which semiconductor PbTe nanocrystals are embedded. This composite exhibits interesting non-linear optical properties in the infrared region, in the range 10-20000 A. The shape and size distribution of the nanocrystals and the kinetics of their growth were studied by small-angle X-ray scattering (SAXS) during in situ isothermal treatment at 923 K. The experimental results indicate that nanocrystals are nearly spherical and have an average radius increasing from 16 to 33 A after 2 h at 923 K, the relative size dispersion being time-invariant and approximately equal to 8%. This investigation demonstrates that the kinetics of nanocrystal growth are governed by the classic mechanism of atomic diffusion. The radius of nanocrystals, deduced by applying the simple Efros and Efros (1982) model using the energy values corresponding to the exciton peaks of optical absorption spectra, does not agree with the average radius determined by SAXS. (orig.)

  8. Volatilization from borosilicate glass melts of simulated Savannah River Plant waste

    International Nuclear Information System (INIS)

    Wilds, G.W.

    1979-01-01

    Laboratory scale studies determined the rates at which the semivolatile components sodium, boron, lithium, cesium, and ruthenium volatilized from borosilicate glass melts that contained simulated Savannah River Plant waste sludge. Sodium and boric oxides volatilize as the thermally stable compound sodium metaborate, and accounted for approx. 90% of the semivolatiles that evolved. The amounts of semivolatiles that evolved increased linearly with the logarithm of the sodium content of the glass-forming mixture. Cesium volatility was slightly suppressed when titanium dioxide was added to the melt, but was unaffected when cesium was added to the melt as a cesium-loaded zeolite rather than as a cesium carbonate solution. Volatility of ruthenium was not suppressed when the glass melt was blanketed with a nonoxidizing atmosphere. Trace quantities of mercury were removed from vapor streams by adsorption onto a silver-exchanged zeolite. A bed containing silver in the ionic state removed more than 99.9% of the mercury and had a high chemisorption capacity. Beds of lead-, copper-, and copper sulfide-exchanged zeolite-X and also an unexchanged zeolite-X were tested. None of these latter beds had high removal efficiency and high chemisorption capacity

  9. High-level waste borosilicate glass: A compendium of corrosion characteristics. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Cunnane, J.C. [comp.; Bates, J.K.; Bradley, C.R. [Argonne National Lab., IL (United States)] [and others

    1994-03-01

    The objective of this document is to summarize scientific information pertinent to evaluating the extent to which high-level waste borosilicate glass corrosion and the associated radionuclide release processes are understood for the range of environmental conditions to which waste glass may be exposed in service. Alteration processes occurring within the bulk of the glass (e.g., devitrification and radiation-induced changes) are discussed insofar as they affect glass corrosion.This document is organized into three volumes. Volumes I and II represent a tiered set of information intended for somewhat different audiences. Volume I is intended to provide an overview of waste glass corrosion, and Volume 11 is intended to provide additional experimental details on experimental factors that influence waste glass corrosion. Volume III contains a bibliography of glass corrosion studies, including studies that are not cited in Volumes I and II. Volume I is intended for managers, decision makers, and modelers, the combined set of Volumes I, II, and III is intended for scientists and engineers working in the field of high-level waste.

  10. Physical and optical properties of lithium borosilicate glasses doped with Dy3+ ions

    Science.gov (United States)

    Ramteke, D. D.; Gedam, R. S.; Swart, H. C.

    2018-04-01

    The borosilicate glasses with Dy3+ ions were prepared by the melt quench technique with varying concentration of Dy2O3. The glasses were characterized by the density calculation, absorbance and photoluminescence (PL) spectroscopy measurements. Density and molar volume of the glasses increases with increase in Dy3+ ions in the glass matrix. This behavior is correlated with the higher molecular weight and larger ionic radius of Dy3+ ion compared to the other constituents of glass matrix. Emission of Dy3+ doped glasses showed three bands at 482, 573 and at 665 nm which correspond to 6H15/2 (blue), 6H13/2 (yellow) and 6H11/2 (red) transitions. The emission spectra of glasses with different concentration of Dy3+ ions shows that, glasses with 0.5 mol% of Dy2O3 shows highest emission and decreases with further doping. CIE 1931 chromaticity diagram showed that the emission of these glasses was in the white region. Photographs of these glasses under 349 nm Light emitting diode excitation also confirmed the white light emission from these glasses.

  11. Study of Structural Properties of Mesoporous Carbon From Fructose with Zinc Borosilicate Activator

    Directory of Open Access Journals (Sweden)

    Tutik Setianingsih

    2014-04-01

    Full Text Available Structural properties, including pore structure, functional group of carbon surface, and crystal structure of carbon built by zinc borosilicate (ZBS and ZnCl2 (Z have been investigated in this work. Physically, ZBS and ZnCl2 may act as template of carbon, whereas the Zn(II cation act as chemical activator of carbonization. All precursors of ZBS (silicagel, boric acid, and ZnCl2 may act as catalysts of caramelization. The caramelization was conducted hydrothermally at 85oC and thermally 130oC. The carbonization was conducted at 450oC. The resulted carbons were washed by using HF 48% solution, 1M HCl solution, and aquadest respectively. The solid products were characterized by using nitrogen gas adsorption, infrared spectrophotometry, X-ray diffraction, and Transmition Electron Microscopy. Result of research showed that ZBS built larger mesopore volume, larger pore domination of pore size, more hydrophobic carbon, and more amorf than ZnCl2.

  12. Luminescence properties of Dy3+ doped lithium zinc borosilicate glasses for photonic applications

    Directory of Open Access Journals (Sweden)

    N. Jaidass

    2018-03-01

    Full Text Available Different concentrations of Dy3+ ions doped lithium zinc borosilicate glasses of chemical composition (30-x B2O3 - 25 SiO2 -10 Al2O3 -30 LiF - 5 ZnO - x Dy2O3 (x = 0, 0.1, 0.5, 1.0 and 2.0 mol% were prepared by the melt quenching technique. The prepared glasses were investigated through X-ray diffraction, optical absorption, photoluminescence and decay measurements. Intensities of absorption bands expressed in terms of oscillator strengths (f were used to determine the Judd-Ofelt (J-O intensity parameters Ωλ (λ = 2, 4 and 6. The evaluated J-O parameters were used to determine the radiative parameters such as transition probabilities (AR, total transition probability rate (AT, radiative lifetime (τR and branching ratios (βR for the excited 4F9/2 level of Dy3+ ions. The chromaticity coordinates determined from the emission spectra were found to be located in the white light region of CIE chromaticity diagram. Keywords: Condensed matter physics, Engineering, Materials science

  13. 3 and 4 oxidation state element solubilities in borosilicate glasses. Implement to actinides in nuclear glasses

    International Nuclear Information System (INIS)

    Cachia, J.N.

    2005-12-01

    In order to ensure optimal radionuclides containment, the knowledge of the actinide loading limits in nuclear waste glasses and also the comprehension of the solubilization mechanisms of these elements are essential. A first part of this manuscript deals with the study of the differences in solubility of the tri and tetravalent elements (actinides and surrogates) particularly in function of the melting temperature. The results obtained indicate that trivalent elements (La, Gd, Nd, Am, Cm) exhibit a higher solubility than tetravalent elements (Hf, Th, Pu). Consequently, it was planned to reduce plutonium at the oxidation state (III), the later being essentially tetravalent in borosilicate glasses. An innovating reduction process of multi-valent elements (cerium, plutonium) using silicon nitride has been developed in a second part of this work. Reduced plutonium-bearing glasses synthesized by Si 3 N 4 addition made it possible to double the plutonium solubility from 2 to 4 wt% at 1200 deg C. A structural approach to investigate the differences between tri and tetravalent elements was finally undertaken. These investigations were carried out by X-rays Absorption Spectroscopy (EXAFS) and NMR. Trivalent rare earth and actinide elements seem to behave as network modifiers while tetravalent elements rather present true intermediaries' behaviour. (author)

  14. Investigation of U3O8 immobilization in the GP-91 borosilicate glass by induction melter with a cold crucible (CCIM)

    International Nuclear Information System (INIS)

    Matyunin, Y.I.; Demin, A.V.; Smelova, T.V.; Yudintsev, S.V.; Lapina, M.I.

    1997-01-01

    One of the most promising and intensively developed methods for the solidification of high-level wastes is their vitrification with the use of a cold crucible induction melter (CCIM), which offers a number of advantages over ceramic melter. This work is concerned with comparison studies on the behavior of uranium in vitreous borosilicate materials synthesized by the traditional technique (melting in muffle furnaces) and CCIM method. The incorporation of uranium oxide U 3 O 8 into the GP-91 borosilicate glass with the use of CCIM technology is investigated. The limiting solubility of uranium in the GP-91 borosilicate glass is evaluated. The phase composition of precipitated dispersed particles based on uranium is determined. Some physicochemical properties of synthesized materials are explored. Investigations into the behavior of uranium in borosilicate glass prepared in the CCIM show a feasibility to synthesize the X-ray amorphous homogeneous borosilicate glasses incorporating as much as 25 - 28 wt% uranium, which is 4 - 5 times larger than that in glasses obtained by the traditional method. (author)

  15. Laser-assisted fabrication of gold nanoparticle-composed structures embedded in borosilicate glass

    Directory of Open Access Journals (Sweden)

    Nikolay Nedyalkov

    2017-11-01

    Full Text Available We present results on laser-assisted formation of two- and three-dimensional structures comprised of gold nanoparticles in glass. The sample material was gold-ion-doped borosilicate glass prepared by conventional melt quenching. The nanoparticle growth technique consisted of two steps – laser-induced defect formation and annealing. The first step was realized by irradiating the glass by nanosecond and femtosecond laser pulses over a wide range of fluences and number of applied pulses. The irradiation by nanosecond laser pulses (emitted by a Nd:YAG laser system induced defect formation, expressed by brown coloration of the glass sample, only at a wavelength of 266 nm. At 355, 532 and 1064 nm, no coloration of the sample was observed. The femtosecond laser irradiation at 800 nm also induced defects, again observed as brown coloration. The absorbance spectra indicated that this coloration was related to the formation of oxygen deficiency defects. After annealing, the color of the irradiated areas changed to pink, with a corresponding well-defined peak in the absorbance spectrum. We relate this effect to the formation of gold nanoparticles with optical properties defined by plasmon excitation. Their presence was confirmed by high-resolution TEM analysis. No nanoparticle formation was observed in the samples irradiated by nanosecond pulses at 355, 532 and 1064 nm. The optical properties of the irradiated areas were found to depend on the laser processing parameters; these properties were studied based on Mie theory, which was also used to correlate the experimental optical spectra and the characteristics of the nanoparticles formed. We also discuss the influence of the processing conditions on the characteristics of the particles formed and the mechanism of their formation and demonstrate the fabrication of structures composed of nanoparticles inside the glass sample. This technique can be used for the preparation of 3D nanoparticle systems

  16. Leaching of the simulated borosilicate waste glasses and spent nuclear fuel under a repository condition

    International Nuclear Information System (INIS)

    Kim, Seung Soo; Chun, Kwan Sik; Kang, Chul Hyung; Suh, Hang Suk

    2002-12-01

    Leaching behaviors of simulated waste glass and spent fuel, contacted on bentonite blocks, in synthetic granitic groundwater were investigated in this study. The leach rate of boron from borosilicate waste glass between the compacted bentonite blocks reached about 0.03 gm-2day-1 at 1500 days, like as that of molybdenum. However, the concentration of uranium in leachate pass through bentonite blocks was less than their detection limits of 2 μg/L and whose yellow amorphous compound was found on the surface of glass contacted with the bentonite blocks. The leaching mechanism of waste glasses differed with their composition. The release rate of cesium from PWR spent fuel in the simulated granitic water without bentonite was leas than $1.0x10 -5 fraction/day after 300 days. The retardation factor of cesium by a 10 -mm thickness of bentonite block was more than 100 for 4-years leaching time. The cumulative release fraction of uranium for 954 days was 0.016% (1.7x10 -7 fraction/day) in granitic water without bentonite. The gap inventory of cesium for spent fuel G23-J11 was 0.15∼0.2%. However, the release of cesium from C15-I08 was 0.9% until 60 days and has being continued after that. Gap inventories of strontium and iodine in G23-J11 were 0.033% and below 0.2%, respectively. The sum of fraction of cesium in gap and grain boundary of G23-J11 was suggested below 3% and less

  17. Synthesis, electrical and magnetic properties of sodium borosilicate glasses containing Co-ferrites nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Othman, H.A. [Department of Physics, Faculty of Science, Menoufia University, Shibin El-Kom 32511, Menoufia (Egypt); Eltabey, M.M. [Department of Basic Engineering Science, Faculty of Engineering, Menoufia University, Shibin El-Kom, Menoufia (Egypt); Department of Physics, Faculty of Science, Jazan University (Saudi Arabia); Ibrahim, Samia E.; El-Deen, L.M. Sharaf; Elkholy, M.M. [Department of Physics, Faculty of Science, Menoufia University, Shibin El-Kom 32511, Menoufia (Egypt)

    2017-02-01

    Co-ferrites nanoparticles that have been prepared by the co-precipitation method were added to sodium borosilicate (Na{sub 2}O–B{sub 2}O{sub 3}–SiO{sub 2}) glass matrix by the solid solution method and they were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and magnetization measurements. (XRD) revealed the formation of the Co-ferrite magnetic crystalline phase embedded in an amorphous matrix in all the samples. The investigated samples by (TEM) showed the formation of the cobalt ferrite nanoparticles with a spherical shape and highly monodispersed with an average size about 13 nm. IR data revealed that the BO{sub 3} and BO{sub 4} are the main structural units of these samples network. IR spectra of the investigated samples showed the characteristic vibration bands of Co-ferrite. Composition and frequency dependent dielectric properties of the prepared samples were measured at room temperature in the frequency range 100–100 kHz. The conductivity was found to increase with increasing cobalt ferrite content. The variations of conductivity and dielectric properties with frequency and composition were discussed. Magnetic hysteresis loops were traced at room temperature using VSM and values of saturation magnetization M{sub S} and coercive field H{sub C} were determined. The obtained results revealed that a ferrimagnetic behavior were observed and as Co-ferrite concentration increases the values of M{sub S} and H{sub C} increase from 2.84 to 8.79 (emu/g) and from 88.4 to 736.3 Oe, respectively.

  18. Integrated Optic Surface Plasmon Resonance Measurements in a Borosilicate Glass Substrate

    Directory of Open Access Journals (Sweden)

    Antonino Parisi

    2008-11-01

    Full Text Available The surface plasmon resonance (SPR technique is a well-known optical method that can be used to measure the refractive index of organic nano-layers adsorbed on a thin metal film. Although there are many configurations for measuring biomolecular interactions, SPR-based techniques play a central role in many current biosensing experiments, since they are the most suited for sensitive and quantitative kinetic measurements. Here we give some results from the analysis and numerical elaboration of SPR data from integrated optics experiments in a particular borosilicate glass, chosen for its composition offering the rather low refractive index of 1.4701 at 633 nm wavelength. These data regard the flow over the sensing region (metal window of different solutions with refractive indexes in the range of interest (1.3÷1.5 for the detection of contaminants in aqueous solutions. After a discussion of the principles of SPR, of the metal window design optimization by means of optical interaction numerical modeling, and of waveguide fabrication techniques, we give a description of system setup and experimental results. Optimum gold film window thickness and width in this guided-wave configuration has been for the first time derived and implemented on an integrated optic prototype device. Its characterization is given by means of the real time waveguide output intensity measurements, which correspond to the interaction between the sensing gold thin film window and the flowing analyte. The SPR curve was subsequently inferred. Finally, a modified version of the device is reported, with channel waveguides arranged in a Y-junction optical circuit, so that laser source stability requirements are lowered by a factor of 85 dB, making possible the use of low cost sources in practical applications.

  19. Structural and crystallisation study of a rare earth alumino borosilicate glass designed for nuclear waste confinement

    International Nuclear Information System (INIS)

    Quintas, A.

    2007-09-01

    This work is devoted to the study of a rare earth alumino borosilicate glass, which molar composition is 61,81 SiO 2 - 3,05 Al 2 O 3 - 8,94 B 2 O 3 - 14,41 Na 2 O - 6,33 CaO - 1,90 ZrO 2 - 3,56 Nd 2 O 3 , and envisaged for the immobilization of nuclear wastes originating from the reprocessing of high discharge burn up spent fuel. From a structural viewpoint, we investigated the role of the modifier cations on the arrangement of the glass network through different modifications of the glass composition: variation of the Na/Ca ratio and modification of the nature of the alkali and alkaline earth cations. The NMR and Raman spectroscopic techniques were useful to determine the distribution of modifier cations among the glass network and also to cast light on the competition phenomena occurring between alkali and alkaline earth cations for charge compensation of [AlO 4 ] - and [BO 4 ] - species. The neodymium local environment could be probed by optical absorption and EXAFS spectroscopies which enabled to better understand the insertion mode of Nd 3+ ions among the silicate domains of the glass network. Concerning the crystallization behavior we were interested in how the glass composition may influence the crystallization processes and especially the formation of the apatite phase of composition Ca 2 Nd 8 (SiO 4 ) 6 O 2 . In particular, this work underlined the important role of both alkaline earth and rare earth cations on the crystallization of the apatite phase. (author)

  20. Borosilicate glass as a matrix for immobilization of SRP high-level waste

    International Nuclear Information System (INIS)

    Wicks, G.G.

    1980-01-01

    Approximately 22 million gallons of high-level radioactive defense waste are currently being stored in large underground tanks located on the Savannah River Plant (SRP) site in Aiken, South Carolina. One option now being considered for long-term management of this waste involves removing the waste from the tanks, chemically processing the waste, and immobilizing the potentially harmful radionuclides in the waste into a borosilicate glass matrix. The technology for producing waste glass forms is well developed and has been demonstrated on various scales using simulated as well as radioactive SRP waste. Recently, full-scale prototypical equipment has been made operational at SRP. This includes both a joule-heated ceramic melter and an in-can melter. These melters are a part of an integrated vitrification system which is under evaluation and includes a spray calciner, direct liquid feed apparatus, and various elements of an off-gas system. Two of the most important properties of the waste glass are mechanical integrity and leachability. Programs are in progress at SRL aimed at minimizing thermally induced cracking by carefully controlling cooling cycles and using ceramic liners or coatings. The leachability of SRP waste glass has been studied under many different conditions and consistently found to be low. For example, the leachability of actual SRP waste glass was found to be 10 -6 to 10 -5 g/(cm 2 )(day) initially and decreasing to 10 -9 to 10 -8 g/(cm 2 )(day) after 100 days. Waste glass is also being studied under anticipated storage conditions. In brine at 90 0 C, the leachability is about 5 x 10 -8 g/(cm 2 )(day) after 60 days. The effects of other geological media including granite, basalt, shale, and tuff are also being studied as part of the multibarrier isolation system

  1. Quantitative estimation of electro-osmosis force on charged particles inside a borosilicate resistive-pulse sensor.

    Science.gov (United States)

    Ghobadi, Mostafa; Yuqian Zhang; Rana, Ankit; Esfahani, Ehsan T; Esfandiari, Leyla

    2016-08-01

    Nano and micron-scale pore sensors have been widely used for biomolecular sensing application due to its sensitive, label-free and potentially cost-effective criteria. Electrophoretic and electroosmosis are major forces which play significant roles on the sensor's performance. In this work, we have developed a mathematical model based on experimental and simulation results of negatively charged particles passing through a 2μm diameter solid-state borosilicate pore under a constant applied electric field. The mathematical model has estimated the ratio of electroosmosis force to electrophoretic force on particles to be 77.5%.

  2. X-ray absorption studies of chlorine valence and local environments in borosilicate waste glasses

    International Nuclear Information System (INIS)

    McKeown, David A.; Gan, Hao; Pegg, Ian L.; Stolte, W.C.; Demchenko, I.N.

    2011-01-01

    Chlorine (Cl) is a constituent of certain types of nuclear wastes and its presence can affect the physical and chemical properties of silicate melts and glasses developed for the immobilization of such wastes. Cl K-edge X-ray absorption spectra (XAS) were collected and analyzed to characterize the unknown Cl environments in borosilicate waste glass formulations, ranging in Cl-content from 0.23 to 0.94 wt.%. Both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) data for the glasses show trends dependent on calcium (Ca) content. Near-edge data for the Ca-rich glasses are most similar to the Cl XANES of CaCl 2 , where Cl - is coordinated to three Ca atoms, while the XANES for the Ca-poor glasses are more similar to the mineral davyne, where Cl is most commonly coordinated to two Ca in one site, as well as Cl and oxygen nearest-neighbors in other sites. With increasing Ca content in the glass, Cl XANES for the glasses approach that for CaCl 2 , indicating more Ca nearest-neighbors around Cl. Reliable structural information obtained from the EXAFS data for the glasses is limited, however, to Cl-Cl, Cl-O, and Cl-Na distances; Cl-Ca contributions could not be fit to the glass data, due to the narrow k-space range available for analysis. Structural models that best fit the glass EXAFS data include Cl-Cl, Cl-O, and Cl-Na correlations, where Cl-O and Cl-Na distances decrease by approximately 0.16 A as glass Ca content increases. XAS for the glasses indicates Cl - is found in multiple sites where most Cl-sites have Ca neighbors, with oxygen, and possibly, Na second-nearest neighbors. EXAFS analyses suggest that Cl-Cl environments may also exist in the glasses in minor amounts. These results are generally consistent with earlier findings for silicate glasses, where Cl - was associated with Ca 2+ and Na + in network modifier sites.

  3. Optical properties of 3d transition metal ion-doped sodium borosilicate glass

    International Nuclear Information System (INIS)

    Wen, Hongli; Tanner, Peter A.

    2015-01-01

    Graphical abstract: Photographs of undoped (SiO 2 ) 50 (Na 2 O) 25 (B 2 O 3 ) 25 (SiNaB) glass and transition metal ion-doped (TM) 0.5 (SiO 2 ) 49.5 (Na 2 O) 25 (B 2 O 3 ) 25 glass samples. - Highlights: • 3d transition metal ion (from Ti to Zn) doped SiO 2 -Na 2 O-B 2 O 3 glasses. • Optical properties of doped glasses investigated. • V(IV,V); Cr(III, VI); Mn(II,III); Fe(II,III); Co(II); Ni(II); Cu(II) by XANES, DRS. • Strong visible absorption but only vanadium ion gives strong emission in glass. - Abstract: SiO 2 -Na 2 O-B 2 O 3 glasses doped with 3d-transition metal species from Ti to Zn were prepared by the melting-quenching technique and their optical properties were investigated. The X-ray absorption near edge spectra of V, Cr, and Mn-doped glasses indicate that the oxidation states of V(IV, V), Cr(III, VI) and Mn(II, III) exist in the studied glasses. The oxidation states revealed from the diffuse reflectance spectra of the glasses are V(IV, V), Cr(III, VI), Mn(III), Fe(II, III), Co(II), Ni(II), and Cu(II). Most of the 3d transition element ions exhibit strong absorption in the visible spectral region in the glass. Under ultraviolet excitation, the undoped sodium borosilicate glass produces weak and broad emission, while doping of vanadium introduces strong and broad emission due to the V(V) charge transfer transition. Only weak emission is observed from Ti(IV), Mn(II), Fe(III) and Cu(II), partly resulting from the strong electron–phonon coupling of the 3d-electrons and the relatively high phonon energy of the studied glass host, with the former leading to dominant nonradiative relaxation based on multiphonon processes for most of the 3d excited states

  4. GLASS FABRICATION AND PRODUCT CONSISTENCY TESTING OF LANTHANIDE BOROSILICATE FRIT X COMPOSITION FOR PLUTONIUM DISPOSITION

    Energy Technology Data Exchange (ETDEWEB)

    Marra, J

    2006-11-15

    The Department of Energy Office of Environmental Management (DOE/EM) plans to conduct the Plutonium Disposition Project at the Savannah River Site (SRS) to disposition excess weapons-usable plutonium. A plutonium glass waste form is the preferred option for immobilization of the plutonium for subsequent disposition in a geologic repository. A reference glass composition (Lanthanide Borosilicate (LaBS) Frit B) was developed during the Plutonium Immobilization Program (PIP) to immobilize plutonium in the late 1990's. A limited amount of performance testing was performed on this baseline composition before efforts to further pursue Pu disposition via a glass waste form ceased. Recent FY05 studies have further investigated the LaBS Frit B formulation as well as development of a newer LaBS formulation denoted as LaBS Frit X. The objectives of this present task were to fabricate plutonium loaded LaBS Frit X glass and perform corrosion testing to provide near-term data that will increase confidence that LaBS glass product is suitable for disposal in the Yucca Mountain Repository. Specifically, testing was conducted in an effort to provide data to Yucca Mountain Project (YMP) personnel for use in performance assessment calculations. Plutonium containing LaBS glass with the Frit X composition with a 9.5 wt% PuO{sub 2} loading was prepared for testing. Glass was prepared to support Product Consistency Testing (PCT) at Savannah River National Laboratory (SRNL). The glass was thoroughly characterized using x-ray diffraction (XRD) and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS) prior to performance testing. A series of PCTs were conducted at SRNL using quenched Pu Frit X glass with varying exposed surface areas. Effects of isothermal and can-in-canister heat treatments on the Pu Frit X glass were also investigated. Another series of PCTs were performed on these different heat-treated Pu Frit X glasses. Leachates from all these PCTs

  5. Results of Vertical Scanning Interferometry (VSI) of Dissolved Borosilicate Glass: Evidence for Variable Surface Features and Global Surface Retreat

    Energy Technology Data Exchange (ETDEWEB)

    Icenhower, Jonathan P.; Luttge, Andreas; McGrail, B. Peter; Beig, Mikhala S.; Arvidson, Rolf S.; Cordova, Elsa A.; Steele, Jackie L.; Baum, Steven R.

    2003-10-29

    Two disparate reaction mechanisms have been invoked to explain the reactivity of glass in contact with aqueous solution. One model is based on arguments from Transition State Theory (TST), which postulates that glass dissolution rates are surface reaction controlled. Alternatively, the second model argues that release of elements from glass to solution is governed by diffusion through an altered layer that forms on the surface of glass. Vertical Scanning Interferometry (VSI) is a new technique that allows one to observe surface features of specimens exposed to solution and may, potentially, be used to distinguish between competing models. We performed a series of dissolution experiments with a suite of glass compositions from chemically simple (sodium borosilicate) to complex (sixteen component borosilicate). Dissolution rates were determined using single-pass flow-through (SPFT) apparatus at 90ºC and pH = 9 and over a solution saturation interval. Upon termination of the experiments, glass coupons were examined by VSI techniques. Effluent chemistry and VSI measurements indicate a nearly constant rate of 2.2 to 3.4 g m-2 d-1 over the solution interval; rates calculated from both methods are identical within experimental uncertainty. We argue that this glass is phase separated, and propose a model for dissolution based on the relative rates of dissolution of the two glass compositions. The data are consistent with a modified version of TST and indicate the potency of VSI methods to elucidate glass reaction mechanisms.

  6. Optimization of lanthanide borosilicate frit compositions for the immobilization of actinides using a Plackett-Burman/simplex algorithm design

    Energy Technology Data Exchange (ETDEWEB)

    Mesko, M.G. [Univ. of Missouri, Rolla, MO (United States); Meaker, T.F.; Ramsey, W.G.; Marra, J.C.; Peeler, D.K. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1997-12-31

    Immobilization by vitrification is one potential disposition option for a portion of the United States` excess plutonium inventory. Research has been performed at the Savannah River Site (SRS) to determine the optimum composition of a lanthanide borosilicate frit for the vitrification of plutonium using a Plackett-Burman design and simplex algorithm as a statistical tool. This technique uses various response variables to rank and optimize a composition. The variables used in this study correspond to homogeneity, durability, actinide solubility and devitrification after heat-treatment. The optimized frit composition was determined using a constant ThO{sub 2} loading of 20 wt%. No noticeable trends were followed with respect to the individual component which may indicate a relatively robust system able to accommodate variations in the feed. Batches containing various loadings of ThO{sub 2} were melted to determine if actinide solubility was improved in the optimized composition compared to that of a similar lanthanide borosilicate glass. No noticeable improvement in ThO{sub 2} solubility was realized as a result of using this optimization technique.

  7. Effects of adding barium-borosilicate glass to a simplified etch-and-rinse adhesive on radiopacity and selected properties.

    Science.gov (United States)

    Martins, Gislaine Cristine; Meier, Marcia Margarete; Loguercio, Alessandro Dourado; Reis, Alessandra; Gomes, João Carlos; Gomes, Osnara Maria

    2014-04-01

    To evaluate the radiopacity, ultimate tensile strength (UTS), microhardness (KHN), degree of conversion (DC), water sorption (WS) and solubility (SL) of experimental adhesives. Five experimental adhesives with different concentrations of barium-borosilicate oxide microfillers [0% (R0), 30% (R30), 40% (R40), 50% (R50), 60% (R60)] were formulated based on the adhesive system Ambar (FGM). The adhesive Adper Single Bond 2 (SB, 3M ESPE) was used as commercial reference. For the radiopacity (n = 5), KHN (n = 5), WS (n = 10), and SL (n = 10) tests, adhesive disks were constructed (5.0 mm in diameter and 1.0 mm thick), while for UTS (n = 5), hourglass-shaped specimens with a cross-sectional area of 0.8 mm2 were used. The FTIR spectra of unpolymerized and polymerized adhesives were used to determine the DC. Data were submitted to a one-way ANOVA and Tukey's test (α = 0.05). All experimental adhesives showed radiopacity similar to enamel, except those of R0 and SB. Filler addition did not jeopardize the UTS, KHN, or WS of the filled adhesives in comparison with the unfilled version. Except for R40, filler addition reduced the SL. The filled adhesives showed lower DC when compared with R0, but the DC was similar or higher when compared with SB. The addition of barium-borosilicate glass up to 50% did not jeopardize the mechanical properties of the adhesive layer and seems to reduce its solubility.

  8. Microwave Absorption of Barium Borosilicate, Zinc Borate, Fe-Doped Alumino-Phosphate Glasses and Its Raw Materials

    Directory of Open Access Journals (Sweden)

    Ashis Kumar Mandal

    2015-05-01

    Full Text Available This study presents microwave absorption of raw materials used in barium borosilicate, Fe-doped alumina phosphate and zinc borate glass. Microwave absorption was investigated for the raw materials SiO2, Na2CO3, BaCO3, BPO4, Al(PO33, Mg(PO32, Al(OH3, TiO2. The study shows that SiO2 could be heated directly above 1000 °C within 30 min at 1.5 kW microwave output (MW power and 0.8 kW MW power is necessary to initiate heating (from 260 °C. Microwave heating of material with low dielectric loss has been investigated by increasing MW power. Microwave absorption of above glass systems has also been investigated. Dielectric properties such as loss tangent of glass as a function of temperature are presented. Glass melting under direct microwave heating was demonstrated for the studied glass systems. Temperature-Microwave power-Time (T-P-t profiles for the three glasses indicate maximum MW output power ~1 kW, 0.65 kW and ~1 kW for barium borosilicate, zinc borate glass and alumino-phosphate glass for 60 g glass melting.

  9. Investigation of local environment around rare earths (La and Eu) by fluorescence line narrowing during borosilicate glass alteration

    Energy Technology Data Exchange (ETDEWEB)

    Molières, Estelle [CEA – DEN-DTCD-LCV-SECM Laboratoire d' études du Comportement à Long Terme, 30207 Bagnols-sur-Cèze (France); Panczer, Gérard; Guyot, Yannick [Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne cedex (France); Jollivet, Patrick [CEA – DEN-DTCD-LCV-SECM Laboratoire d' études du Comportement à Long Terme, 30207 Bagnols-sur-Cèze (France); Majérus, Odile; Aschehoug, Patrick; Barboux, Philippe [Laboratoire de Chimie de la Matière Condensée de Paris, UMR-CNRS 7574, École Nationale Supérieure de Chimie de Paris (ENSCP Chimie-ParisTech), 11 rue Pierre et Marie Curie, 75231 Paris (France); Gin, Stéphane [CEA – DEN-DTCD-LCV-SECM Laboratoire d' études du Comportement à Long Terme, 30207 Bagnols-sur-Cèze (France); Angeli, Frédéric, E-mail: frederic.angeli@cea.fr [CEA – DEN-DTCD-LCV-SECM Laboratoire d' études du Comportement à Long Terme, 30207 Bagnols-sur-Cèze (France)

    2014-01-15

    The local environment of europium in soda-lime borosilicate glasses with a range of La{sub 2}O{sub 3} content was probed by continuous luminescence and Fluorescence Line Narrowing (FLN) to investigate the local environment of rare earth elements in pristine and leached glass. After aqueous leaching at 90 °C at pH 7 and 9.5, rare earths were fully retained and homogeneously distributed in the amorphous alteration layer (commonly called gel). Two separate silicate environments were observed in pristine and leached glasses regardless of the lanthanum content and the leaching conditions. A borate environment surrounding europium was not observed in pristine and leached glasses. During glass alteration, OH groups were located around the europium environment, which became more organized (higher symmetry) in the first coordination shell. -- Highlights: • No borate environment surrounding europium was detected in pristine borosilicate glasses. • Up to 12 mol% of REE2O3 in glass, local environment of europium does not significantly change. • Europium environment becomes more ordered and symmetric in gels than in pristine glasses. • Two distinct silicate sites were observed, as well in pristine glass as in gels (leached glasses). • In altered glasses, OH groups were located around europium.

  10. Structure, thermal stability and resistance under external irradiation of rare earths and molybdenum-rich alumino-borosilicate glasses

    International Nuclear Information System (INIS)

    Chouard, N.

    2011-01-01

    In France, the highly radioactive nuclear liquid wastes arising from spent nuclear fuel reprocessing (fission products + minor actinides (FPA)) are currently immobilized in an alumino-borosilicate glass called 'R7T7'. In the future, the opportunity of using new alumino-borosilicate glass compositions (HTC glasses) is considered in order to increase the waste loading in glasses and thus significantly decrease the number of glass canisters. However, the increase of the concentration of FPA could lead to the crystallization of rare-earth-rich phases (Ca 2 RE 8 (SiO 4 ) 6 O 2 ) or molybdenum-rich phases (CaMoO 4 , Na 2 MoO 4 ) during melt cooling, which can modify the confinement properties of the glass (chemical durability, self-irradiation resistance..), particularly if they can incorporate radionuclides α or β in their structure. This thesis can be divided into two parts: The first part deals with studying the relationship that can occur between the composition, the structure and the crystallization tendency of simplified seven oxides glasses, belonging to the SiO 2 -B 2 O 3 -Al 2 O 3 -Na 2 O-CaO-MoO 3 -Nd 2 O 3 system and derived from the composition of the HTC glass at 22,5 wt. % in FPA. The impact of the presence of platinoid elements (RuO 2 in our case) on the crystallization of the different phases is also studied. The second part deals with the effect of actinides α decays and more particularly of nuclear interactions essentially coming from recoil nuclei (simulated here by heavy ions external irradiations) on the behaviour under irradiation of an alumino-borosilicate glass containing apatite Ca 2 Nd 8 (SiO 4 ) 6 O 2 crystals, that can incorporate actinides in their structure. Two samples containing apatite crystals with different size are studied, in order to understand the impact of microstructure on the irradiation resistance of this kind of material. (author) [fr

  11. Phase evolution and dielectric properties of MgTi2O5 ceramic sintered with lithium borosilicate glass

    International Nuclear Information System (INIS)

    Shin, Hyunho; Shin, Hee-Kyun; Jung, Hyun Suk; Cho, Seo-Yong; Hong, Kug Sun

    2005-01-01

    Phase evolution, densification, and dielectric properties of MgTi 2 O 5 dielectric ceramic, sintered with lithium borosilicate (LBS) glass, were studied. Reaction between LBS glass and MgTi 2 O 5 was significant in forming secondary phases such as TiO 2 and (Mg,Ti) 2 (BO 3 )O. The glass addition was not necessarily deleterious to the dielectric properties due to the formation of TiO 2 : permittivity increased and temperature coefficient of resonance frequency could be tuned to zero with the addition of LBS glass, although the inevitable glass-induced decrease of quality factor was not retarded by the formation of TiO 2 . The sintered specimen with 10 wt% LBS fired at 950 deg. C for 2 h showed permittivity of 19.3, quality factor of 6800 GHz, and τ f of -16 ppm/ deg. C

  12. Effect of 10B(n, α)7Li irradiation on the structure of a sodium borosilicate glass

    Science.gov (United States)

    Peuget, S.; Fares, T.; Maugeri, E. A.; Caraballo, R.; Charpentier, T.; Martel, L.; Somers, J.; Janssen, A.; Wiss, T.; Rozenblum, F.; Magnin, M.; Deschanels, X.; Jégou, C.

    2014-05-01

    The effects of the nuclear reaction 10B(n, α)7Li on the properties and structure of a sodium borosilicate glass were analysed by density, hardness and fracture toughness measurements, Raman and Nuclear Magnetic Resonance spectroscopy and Transmission Electronic Microscopy (TEM) characterization. The TEM observations showed a homogeneous irradiated glass structure up to the nanometer scale. Modifications of the local order around the main cations were noticed, mainly a slight decrease of the mean boron coordination number and an increase of non-bridging oxygen concentrations. At the glass medium range order, the appearance of the D2 Raman band and a modification of the Si-O-Si angle distribution were also observed after irradiation.

  13. Investigating the effect of V{sub 2}O{sub 5} addition on sodium barium borosilicate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Halder, Rumu, E-mail: rumuhalder24feb@gmail.com; Sengupta, Pranesh; Dey, G. K. [Materials Science Division, Bhabha Atomic Research Centre, Mumbai-700 085 (India); Sudarsan, V. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai-700 085 (India); Kaushik, C. P. [Waste Management Division, Bhabha Atomic Research Centre, Mumbai-700 085 (India)

    2016-05-23

    V{sub 2}O{sub 5} doped sodium barium borosilicate glasses were characterized by photoluminescence spectroscopy and electron probe microanalyzer (EPMA). The glass remains homogeneous for lower concentration of V{sub 2}O{sub 5} but a phase separation is observed when V{sub 2}O{sub 5} doping is increased beyond 5 mol%. Detailed microanalysis reveals that the phase separated glass consists of a phase containing V, Ba and Si and a separate Si rich phase within the glass matrix. The luminescence study demonstrated that at low concentration the vanadium mainly interacts with the structural units of B/Si while at higher concentrations, V-O-V/ V-O{sup −} Na{sup +}/Ba{sup 2+} linkages are formed.

  14. Local structure near actinides and nucleating elements in borosilicate glass for nuclear industry: Results of X-ray absorption spectroscopy

    International Nuclear Information System (INIS)

    Petit-Maire, D.

    1988-01-01

    Possibilities and limits of X-ray absorption spectroscopy for cation site description in silicate glasses and possible applications for complex glasses, like glass for fission product containment, are examined. In borosilicate glasses two types of sites are evidenced for actinides at the valence 4: Coordinance 6 sites with a narrow radial distribution for the distance An-0; higher coordination (7, 8 or more) with a wider and asymmetrical radial distribution. Proportion of low coordinance sites increases when cation size decreases (Th > Np). U and Np VI and V are characterized as actinyles with a chain 0-An-0 practically linear, coordinance in a plane perpendicular to this complex is probably 5. X-ray absorption spectroscopy allows an accurate description of actinide sites in fission product glasses [fr

  15. Upconversion studies of Er3+/Yb3+ doped SrO.TiO2 borosilicate glass ceramic system

    International Nuclear Information System (INIS)

    Maheshwari, Aditya; Om Prakash; Kumar, Devendra; Rai, S.B.

    2011-01-01

    Upconversion behaviour has been studied in various matrices and fine powders of SrTiO 3 by previous workers. In present work, Er 3+ /Yb 3+ were doped in appropriate ratio in SrO.TiO 2 borosilicate glass ceramic system to study the upconversion phenomenon. Dielectric properties of this class of glass ceramic system have been extensively investigated by Thakur et al. It has been observed that both upconversion efficiency and dielectric constant increases with transformation of glass into glass ceramic. Therefore, present investigation is based upon the study of optical as well as the electrical properties of same glass ceramic system. In order to prepare different crystalline matrices, two different Er 3+ /Yb 3+ :SrO.TiO 2 borosilicate glasses with same amount of Er 2 O 3 and Yb 2 O 3 were prepared by melt quench method. Glasses were transparent with light-wine colour. Glass ceramics were prepared from the glasses by heat treatment based on DTA (Differential thermal analysis) results. Glass ceramics were fully opaque with brownish-cream colour. Powder X-ray diffraction (XRD) patterns confirmed that two different crystalline matrices, Sr 3 Ti 2 O 7 , Ti 10 O 19 and SrTiO 3 , TiO 2 were present in two glass ceramic samples respectively. Luminescence properties of glass and glass ceramic samples with 976nm laser irradiation showed that the intensities of the green and red emission increased multiple times in glass ceramic than that of the glass. Possible mechanisms responsible for upconversion eg. Energy Transfer (ET) and Excited State Absorption (ESA), were studied through laser pumping power log dependence

  16. Preparation and nonlinear optical properties of indium nanocrystals in sodium borosilicate glass by the sol–gel route

    International Nuclear Information System (INIS)

    Zhong, Jiasong; Xiang, Weidong; Zhao, Haijun; Chen, Zhaoping; Liang, Xiaojuan; Zhao, Wenguang; Chen, Guoxin

    2012-01-01

    Graphical abstract: The sodium borosilicate glass doped with indium nanocrystals have been successfully prepared by sol–gel methods. And the indium nanocrystals in tetragonal crystal system have formed uniformly in the glass, and the average diameter of indium nanocrystals is about 30 nm. The third-order optical nonlinear refractive index γ, absorption coefficient β, and susceptibility χ (3) of the glass are determined to be −4.77 × 10 −16 m 2 /W, 2.67 × 10 −9 m/W, and 2.81 × 10 −10 esu, respectively. Highlights: ► Indium nanocrystals embedded in glass matrix have been prepared by sol–gel route. ► The crystal structure and composition are investigated by XRD and XPS. ► Size and distribution of indium nanocrystals is determined by TEM. ► The third-order optical nonlinearity is investigated by using Z-scan technique. -- Abstract: The sodium borosilicate glass doped with indium nanocrystals have been successfully prepared by sol–gel route. The thermal stability behavior of the stiff gel is investigated by thermogravimetric (TG) and differential thermal (DTA) analysis. The crystal structure of the glass is characterized by X-ray powder diffraction (XRD). Particle composition is determined by X-ray photoelectron spectroscopy (XPS). Size and distribution of the nanocrystals are characterized by transmission electron microscopy (TEM) as well as high-resolution transmission electron microscopy (HRTEM). Results show that the indium nanocrystals in tetragonal crystal structure have formed in glass, and the average diameter is about 30 nm. Further, the glass is measured by Z-scan technique to investigate the nonlinear optical (NLO) properties. The third-order NLO coefficient χ (3) of the glass is determined to be 2.81 × 10 −10 esu. The glass with large third-order NLO coefficient is promising materials for applications in optical devices.

  17. Basaltic glasses from Iceland and the deep sea: Natural analogues to borosilicate nuclear waste-form glass

    International Nuclear Information System (INIS)

    Jercinovic, M.J.; Ewing, R.C.

    1987-12-01

    The report provides a detailed analysis of the alteration process and products for natural basaltic glasses. Information of specific applicability to the JSS project include: * The identification of typical alteration products which should be expected during the long-term corrosion process of low-silica glasses. The leached layers contain a relatively high proportion of crystalline phases, mostly in the form of smectite-type clays. Channels through the layer provide immediate access of solutions to the fresh glass/alteration layer interface. Thus, glasses are not 'protected' from further corrosion by the surface layer. * Corrosion proceeds with two rates - an initial rate in silica-undersaturated environments and a long-term rate in silica-saturated environments. This demonstrates that there is no unexpected change in corrosion rate over long periods of time. The long-term corrosion rate is consistent with that of borosilicate glasses. * Precipitation of silica-containing phases can result in increased alteration of the glass as manifested by greater alteration layer thicknesses. This emphasizes the importance of being able to predict which phases form during the reaction sequence. * For natural basaltic glasses the flow rate of water and surface area of exposed glass are critical parameters in minimizing glass alteration over long periods of time. The long-term stability of basalt glasses is enhanced when silica concentrations in solution are increased. In summary, there is considerable agreement between corrosion phenomena observed for borosilicate glasses in the laboratory and those observed for natural basalt glasses of great age. (With 121 refs.) (authors)

  18. Utilization of Cs137 to generate a radiation barrier for weapons grade plutonium immobilized in borosilicate glass canisters. Revision 1

    International Nuclear Information System (INIS)

    Jardine, L.J.; Armantrout, G.A.; Collins, L.F.

    1995-01-01

    One of the ways recommended by a recent National Academy of Sciences study to dispose of excess weapons-grade plutonium is to encapsulate the plutonium in a glass in combination with high-level radioactive wastes (HLW) to generate an intense radiation dose rate field. The objective is to render the plutonium as difficult to access as the plutonium contained in existing US commercial spent light-water reactor (LWR) fuel until it can be disposed of in a permanent geological repository. A radiation dose rate from a sealed canister of 1,000 rem/h (10 Sv/h) at 1 meter for at least 30 years after fabrication was assumed in this paper to be a radiation dose comparable to spent LWR fuel. This can be achieved by encapsulating the plutonium in a borosilicate glass with an adequate amount of a single fission product in the HLWS, namely radioactive Cs 137 . One hundred thousand curies of Cs 137 will generate a dose rate of 1,000 rem/h (10 Sv/h) at 1 meter for at least 30 years when imbedded into canisters of the size proposed for the Savannah River Site's vitrified high-level wastes. The United States has a current inventory of 54 MCi of CS 137 that has been separated from defense HLWs and is in sealed capsules. This single curie inventory is sufficient to spike 50 metric tons of excess weapons-grade plutonium if plutonium can be loaded at 5.5 wt% in glass, or 540 canisters. Additional CS 137 inventories exist in the United States' HLWs from past reprocessing operations, should additional curies be required. Using only one fission product, CS 137 , rather than the multiple chemical elements and compounds in HLWs to generate a high radiation dose rate from a glass canister greatly simplifies the processing engineering retirement for encapsulating plutonium in a borosilicate glass

  19. Effect of the Callovian-Oxfordian clayey fraction on borosilicate glass alteration

    International Nuclear Information System (INIS)

    Debure, M.; Frugier, P.; GIN, S.; De Windt, L.; Michau, N.

    2012-01-01

    easily exchangeable Mg and to check whether remaining Mg, especially structural Mg could still feed the solution. The cation exchange capacity (CEC) and the exchangeable cation population after treatment were measured by the cobaltihexamine test, indicating an enrichment of Na (from 14% to 79% in equivalents) of the exchangeable population at the expense of Ca (from 50% to 4%), Mg (from 15% to 6%) and K (from 18% to 7%) compared to the pristine clay-stone. Synthetic borosilicate Mg-free glasses were used as simplified references of the French nuclear glass R7T7. Batch experiments were performed in closed system at 90 deg. C during 150 days. The clay/glass (C/G) weight ratio ranged from 0.01 to 100 for a liquid/solid (L/S) weight ratio of 20. The specific surface was estimated to be around 0.06 m 2 /g and 100 m 2 /g for the glass powder and the clayey fraction, respectively. Chemical analysis of the batch solutions were carried out with time, as well as XRD, SEM and TOF-SIMS analysis of the solids after completion of the batch experiments. Modeling was performed with the GRAAL kinetic model of glass dissolution that considers elements and water diffusion in the alteration layer (Frugier et al., 2008), implemented within the reactive transport code HYTEC (van der Lee et al., 2003). The experiments showed that the higher the clay/glass ratio, the lower the pH 90deg.C and the higher the glass alteration. As shown in Fig. 1, the pH 90deg.C varied from 8.9 for the lowest clay/glass proportion (C/G 1) to 5.4 for the highest one (C/G = 100). The corresponding mean glass dissolution rates are 15 nm/d and 300 nm/d, respectively. A batch test performed with the sole clayey fraction in pure water yielded a pH 90deg.C of 5.2, whereas the test made with the glass alone led to a pH 90deg.C around 9. The main effect of the clayey fraction in the batch tests seems to drop the pH down to more acidic values that concentrations of B (a tracer of the glass alteration) on the one hand, and of

  20. RHENIUM SOLUBILITY IN BOROSILICATE NUCLEAR WASTE GLASS IMPLICATIONS FOR THE PROCESSING AND IMMOBILIZATION OF TECHNETIUM-99 (AND SUPPORTING INFORMATION WITH GRAPHICAL ABSTRACT)

    Energy Technology Data Exchange (ETDEWEB)

    AA KRUGER; A GOEL; CP RODRIGUEZ; JS MCCLOY; MJ SCHWEIGER; WW LUKENS; JR, BJ RILEY; D KIM; M LIEZERS; P HRMA

    2012-08-13

    The immobilization of 99Tc in a suitable host matrix has proved a challenging task for researchers in the nuclear waste community around the world. At the Hanford site in Washington State in the U.S., the total amount of 99Tc in low-activity waste (LAW) is {approx} 1,300 kg and the current strategy is to immobilize the 99Tc in borosilicate glass with vitrification. In this context, the present article reports on the solubility and retention of rhenium, a nonradioactive surrogate for 99Tc, in a LAW sodium borosilicate glass. Due to the radioactive nature of technetium, rhenium was chosen as a simulant because of previously established similarities in ionic radii and other chemical aspects. The glasses containing target Re concentrations varying from 0 to10,000 ppm by mass were synthesized in vacuum-sealed quartz ampoules to minimize the loss of Re by volatilization during melting at 1000 DC. The rhenium was found to be present predominantly as Re7 + in all the glasses as observed by X-ray absorption near-edge structure (XANES). The solubility of Re in borosilicate glasses was determined to be {approx}3,000 ppm (by mass) using inductively coupled plasma-optical emission spectroscopy (ICP-OES). At higher rhenium concentrations, some additional material was retained in the glasses in the form of alkali perrhenate crystalline inclusions detected by X-ray diffraction (XRD) and laser ablation-ICP mass spectrometry (LA-ICP-MS). Assuming justifiably substantial similarities between Re7 + and Tc 7+ behavior in this glass system, these results implied that the processing and immobilization of 99Tc from radioactive wastes should not be limited by the solubility of 99Tc in borosilicate LAW glasses.

  1. Linear thermal expansion coefficient (at temperatures from 130 to 800 K) of borosilicate glasses applicable for coupling with silicon in microelectronics

    OpenAIRE

    Sinev, Leonid S.; Petrov, Ivan D.

    2017-01-01

    Processing results of measurements of linear thermal expansion coefficients and linear thermal expansion of two brands of borosilicate glasses --- LK5 and Borofloat 33 --- are presented. The linear thermal expansion of glass samples have been determined in the temperature range 130 to 800 K (minus 143 to 526 $\\deg$C) using thermomechanical analyzer TMA7100. Relative imprecision of indirectly measured linear thermal expansion coefficients and linear thermal expansion of both glass brands is le...

  2. Determination of the free enthalpies of formation of borosilicate glasses; Determination des enthalpies libres de formation des verres borosilicates. Application a l'etude de l'alteration des verres de confinement de dechets radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Linard, Y

    2000-07-01

    This work contributes to the study of the thermochemical properties of nuclear waste glasses. Results are used to discuss mechanisms and parameters integrated in alteration models of conditioning materials. Glass is a disordered material defined thermodynamically as a non-equilibrium state. Taking into account one order parameter to characterise its configurational state, the metastable equilibrium for the glass was considered and the main thermochemical properties were determined. Calorimetric techniques were used to measure heat capacities and formation enthalpies of borosilicate glasses (from 3 to 8 constitutive oxides). Formation Entropies were measured too, using the entropy theory of relaxation processes proposed by Adam and Gibbs (1965). The configurational entropy contribution were determined from viscosity measurements. This set of data has allowed the calculation of Gibb's free energies of dissolution of glasses in pure water. By comparison with leaching experiments, it has been demonstrated that the decreasing of the dissolution rate at high reaction progress cannot be associated to the approach of an equilibrium between the sound glass and the aqueous solution. The composition changes of the reaction area at the glass surface need to be considered too. To achieve a complete description of the thermodynamic stability, the equilibrium between hydrated de-alkalinized glass and/or the gel layer with the aqueous solution should also be evaluated. (author)

  3. 3 and 4 oxidation state element solubilities in borosilicate glasses. Implement to actinides in nuclear glasses; Solubilite des elements aux degres d'oxydation (3) et (4) dans les verres de borosilicate. Application aux actinides dans les verres nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Cachia, J.N

    2005-12-15

    In order to ensure optimal radionuclides containment, the knowledge of the actinide loading limits in nuclear waste glasses and also the comprehension of the solubilization mechanisms of these elements are essential. A first part of this manuscript deals with the study of the differences in solubility of the tri and tetravalent elements (actinides and surrogates) particularly in function of the melting temperature. The results obtained indicate that trivalent elements (La, Gd, Nd, Am, Cm) exhibit a higher solubility than tetravalent elements (Hf, Th, Pu). Consequently, it was planned to reduce plutonium at the oxidation state (III), the later being essentially tetravalent in borosilicate glasses. An innovating reduction process of multi-valent elements (cerium, plutonium) using silicon nitride has been developed in a second part of this work. Reduced plutonium-bearing glasses synthesized by Si{sub 3}N{sub 4} addition made it possible to double the plutonium solubility from 2 to 4 wt% at 1200 deg C. A structural approach to investigate the differences between tri and tetravalent elements was finally undertaken. These investigations were carried out by X-rays Absorption Spectroscopy (EXAFS) and NMR. Trivalent rare earth and actinide elements seem to behave as network modifiers while tetravalent elements rather present true intermediaries' behaviour. (author)

  4. Deep-UV Raman spectroscopic analysis of structure and dissolution rates of silica-rich sodium borosilicate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Eric M [ORNL; WindischJr., Charles F. [Pacific Northwest National Laboratory (PNNL); Burton, Sarah D. [Pacific Northwest National Laboratory (PNNL); Bovaird, Chase C. [Pacific Northwest National Laboratory (PNNL)

    2010-01-01

    As part of ongoing studies to evaluate relationships between structure and rates of dissolution of silicate glasses in aqueous media, sodium borosilicate glasses of composition Na2O xB2O3 (3 x)SiO2, with x 1 (Na2O/B2O3 ratio 1), were analyzed using deep-UV Raman spectroscopy. Results were quantified in terms of the fraction of SiO4 tetrahedra with one non-bridging oxygen (Q3) and then correlated with Na2O and B2O3 content. The Q3 fractionwas found to increase with increasing Na2O content, in agreement with studies on related glasses, and, as long as the value of x was not too high, this contributed to higher rates of dissolution in single pass flow-through testing. In contrast, dissolution rates were less strongly determined by the Q3 fraction when the value of x was near unity, and appeared to grow larger upon further reduction of the Q3 fraction. Results were interpreted to indicate the increasingly important role of network hydrolysis in the glass dissolution mechanism as the BO4 tetrahedron replaces the Q3 unit as the charge-compensating structure for Na+ ions. Finally, the use of deep-UV Raman spectroscopy was found to be advantageous in studying finely powdered glasses in cases where visible Raman spectroscopy suffered from weak Raman scattering and fluorescence interference.

  5. Study of optical absorption and photoluminescence of quantum dots of CdS formed in borosilicate glass matrix

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Jitender; Verma, A; Pandey, P K; Bhatnagar, P K; Mathur, P C [Department of Electronic Science, University of Delhi South Campus, Benito Juarez Road, New Delhi-110021 (India); Liu, W; Tang, S H [Department of Physics, National University of Singapore, 119243 (Singapore)], E-mail: jitender_does@yahoo.co.in

    2009-06-15

    Optical absorption and photoluminescence (PL) measurements have been made on the quantum dots (QDs) of CdS grown in a borosilicate glass matrix using a two-step annealing technique. The absorption measurements, made in the energy range of 1.3-3.2 eV, indicate the presence of nonradiative trap centers located in the forbidden gap at an energy level near 1.5 eV. The origin of these traps is attributed to the impurities present in the glass matrix. The PL measurements have been made at an excitation energy of 2.75 eV and it is concluded that the origin of PL is not due to either direct recombination of electrons and holes or deep traps, but that it is the shallow traps which are responsible for the observed PL. The shallow traps are attributed to sulfur vacancies formed at the glass-QD interface. The reason for the observed decrease in PL peak intensity with the increase of annealing time is due to the decrease of surface to volume ratio for QDs of higher size.

  6. Enhanced mechanical properties of single walled carbon nanotube-borosilicate glass composite due to cushioning effect and localized plastic flow

    Directory of Open Access Journals (Sweden)

    Sujan Ghosh

    2011-12-01

    Full Text Available A borosilicate glass composite has been fabricated incorporating Single Wall Carbon Nanotubes (SWCNT in the glass matrix by melt-quench technique. Hardness and the fracture toughness of the composite, were found to increase moderately with respect to the base glass. Interestingly one can observe accumulation of SWCNT bundles around the crack zone though no such accumulation was observed in the crack free indentation zone. The enhanced hardness of the composite was discussed by correlating the cushioning as well as toughening behavior of the agglomerated SWCNT bundles. On the other hand enhanced plastic flow was proposed to be the prime reason for the accumulation of SWCNT bundles around the crack, which increases the toughness of the composite by reducing the crack length. Moreover to ascertain the enhanced plasticity of the composite than that of the glass we calculated the recovery resistance of glass and the composite where recovery resistance of composite was found to be higher than that of the glass.

  7. Conversion of plutonium-containing materials into borosilicate glass using the glass material oxidation and dissolution system

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

    1996-01-01

    The end of the cold war has resulted in excess plutonium-containing materials (PCMs) in multiple chemical forms. Major problems are associated with the long-term management of these materials: safeguards and nonproliferation issues; health, environment, and safety concerns; waste management requirements; and high storage costs. These issues can be addressed by conversion of the PCMs to glass: however, conventional glass processes require oxide-like feed materials. Conversion of PCMs to oxide-like materials followed by vitrification is a complex and expensive process. A new vitrification process has been invented, the Glass Material Oxidation and Dissolution System (GMODS) to allow direct conversion of PCMs to glass. GMODS directly converts metals, ceramics, and amorphous solids to glass; oxidizes organics with the residue converted to glass; and converts chlorides to borosilicate glass and a secondary sodium chloride stream. Laboratory work has demonstrated the conversion of cerium (a plutonium surrogate), uranium (a plutonium surrogate), Zircaloy, stainless steel, multiple oxides, and other materials to glass. Equipment options have been identified for processing rates between 1 and 100,000 t/y. Significant work, including a pilot plant, is required to develop GMODS for applications at an industrial scale

  8. Effects of magnesium minerals representative of the Callovian-Oxfordian clay-stone on borosilicate glass alteration

    International Nuclear Information System (INIS)

    Debure, M.

    2012-01-01

    Borosilicate glasses dissolution has been studied in presence of magnesium minerals. Those minerals (dolomite, illite, smectite...) belong to the Callovo-Oxfordian (COx) clay-stone layer, studied in France as a potential site for nuclear waste disposal. Such minerals contain magnesium, an element able to sustain glass alteration when it is available in solution. In the confined media of the wastes disposal, the solids reactivity controls the solution composition and can be the driving force of nuclear glass alteration. Experiments show that magnesium carbonates (hydro-magnesite and dolomite) increase in the glass alteration: the precipitation of magnesium silicates consumes silicon which slows down the formation of the glass passivating layer. The lower the magnesium mineral solubility, the lower the glass alteration. The purified clay phases (illite, smectite...) from the COx layer increase the glass alteration. Half the magnesium was replaced by sodium during the purification process. In such conditions, the effect of clay phases on glass alteration is in part due to the acidic pH-buffering effect of the clay fraction. The GRAAL model implemented in the geochemical transport code HYTEC has confirmed and quantified the mechanisms put in evidence in the experiments. Cells diffusion experiments where the two solids were separated by an inert diffusion barrier allow to valid reactive transport modelling. Such experiments are more representative of the glass package which will be separated from the COx by corrosion products. They show that glass alteration rate is reduced when solids are not close. (author) [fr

  9. Effects of cobalt-60 gamma radiation on the strength-related internal structure of the borosilicate glass

    International Nuclear Information System (INIS)

    Cafe, Arven I.; Liamzon, Angelie J.

    2011-03-01

    Borosilicate glass in the form of glass slides (1.Omm in thickness and cut into 12.5mm x 55.Omm surface area) was examined to determine the reusability or recyclability and strength of glass apparatuses or compartments after exposing to gamma irradiation from Co-60 source. After knowing the initial parameters using EDXRF under six secondary targets, glass specimens prepared was subjected to gamma radiation for doses 3kGy, 6kGy, 15kGy, 25kGy, and 100kGy. Results of characterization under FTIR provides information about the occurred extension of B-O-Si and B-O-B linkages for lower doses (3-25kGy), while destruction of Si-O bonds for higher dose (100kGy). It shows direct relationship on the observed color change from clear ransparent to deep brown corresponding to the change in optical densities as irradiation dose increases. Ability to fade the induced deep brown color was also observed for a certain time interval which satisfies that this type of glass exhibits self healing property. Although, average energy of about 1.25MeV causes rearrangement of atoms within the glass, according to the XRD result, it remained to be an amorphous solid even in higher dose applied which satisfies that remanufacturing and recycling is possible. (author)

  10. Contribution of germanium dioxide to the thermal expansion characteristics of some borosilicate glasses and their corresponding glass-ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Darwish, H.; Salama, S.N.; Salman, S.M. [National Research Centre, Cairo (Egypt). Glass Research Dept.

    2002-07-01

    The thermal expansion characteristics of some lithium aluminium germanium borosilicate glasses and their crystalline solids have been investigated. The base glass composition was modified by partial replacement of germanium dioxide instead of silica. In some cases, however, TiO{sub 2} was also added to some selected glasses as a nucleation catalyst. Slight increase in the thermal expansion coefficient ({alpha}) values of the glasses and corresponding slight decrease in both transition (Tg) and softening (Ts) temperatures are detected by GeO{sub 2}/SiO{sub 2} replacements, however, the reverse results were recorded by TiO{sub 2} addition. The obtained data were correlated to the local structure changes induced by GeO{sub 2} or TiO{sub 2} and their contributions to the thermal expansion property of the glasses. On the crystallization, the expansivity of the glasses was markedly changed. It was greatly affected by crystallization of GeO{sub 2}-containing phases and aluminosilicate solid solutions together with the TiO{sub 2}-containing phases formed. The results obtained were explained in relation to the nature, composition and concentration of all phases formed in the glass-ceramics including a residual glass matrix. (orig.)

  11. In Vitro Degradation of Borosilicate Bioactive Glass and Poly(l-lactide-co-ε-caprolactone Composite Scaffolds

    Directory of Open Access Journals (Sweden)

    Jenna Tainio

    2017-11-01

    Full Text Available Composite scaffolds were obtained by mixing various amounts (10, 30 and 50 weight % [wt %] of borosilicate bioactive glass and poly(l-lactide-co-ε-caprolactone (PLCL copolymer. The composites were foamed using supercritical CO2. An increase in the glass content led to a decrease in the pore size and density. In vitro dissolution/reaction test was performed in simulated body fluid. As a function of immersion time, the solution pH increased due to the glass dissolution. This was further supported by the increasing amount of Ca in the immersing solution with increasing immersion time and glass content. Furthermore, the change in scaffold mass was significantly greater with increasing the glass content in the scaffold. However, only the scaffolds containing 30 and 50 wt % of glasses exhibited significant hydroxyapatite (HA formation at 72 h of immersion. The compression strength of the samples was also measured. The Young’s modulus was similar for the 10 and 30 wt % glass-containing scaffolds whereas it increased to 90 MPa for the 50 wt % glass containing scaffold. Upon immersion up to 72 h, the Young’s modulus increased and then remained constant for longer immersion times. The scaffold prepared could have great potential for bone and cartilage regeneration.

  12. The Effect of Caramelization and Carbonization Temperatures toward Structural Properties of Mesoporous Carbon from Fructose with Zinc Borosilicate Activator

    Directory of Open Access Journals (Sweden)

    Tutik Setianingsih

    2014-10-01

    Full Text Available Mesoporous carbon was prepared from fructose using zinc borosilicate (ZBS activator. The synthesis involves caramelization and carbonization processes. The effect of both process temperature toward porosity and functional group of carbon surface are investigated in this research. The caramelization was conducted hydrothermally at 85 and 100 °C, followed by thermally 130 °C. The carbonization was conducted at various temperatures (450–750 °C. The carbon-ZBS composite were washed by using HF 48% solution, 1M HCl solution, and aquadest respectively to remove ZBS from the carbon. The carbon products were characterized with nitrogen gas adsorption-desorption method, FTIR spectrophotometry, X-ray diffraction, and Transmission Electron Microscopy. The highest mesopore characteristics is achieved at 100 °C (caramelization and 450 °C (carbonization, including Vmeso about 2.21 cm3/g (pore cage and 2.32 cm3/g (pore window with pore uniformity centered at 300 Å (pore cage and 200 Å (pore window, containing the surface functional groups of C=O and OH, degree of graphitization about 57% and aromaticity fraction about 0.68.

  13. Irradiations effects on the structure of boro-silicated glasses: long term behaviour of nuclear waste glassy matrices

    International Nuclear Information System (INIS)

    Bonfils, J. de

    2007-09-01

    This work deals with the long term behaviour of R7T7-type nuclear waste glasses and more particularly of non-active boro-silicated glasses made up of 3 or 5 oxides. Radioactivity of active glasses is simulated by multi energies ions implantations which reproduce the same defects. The damages due to the alpha particles are simulated by helium ions implantations and those corresponding to the recoil nucleus are obtained with gold ions ones. Minor actinides, stemming from the used fuel, is simulated by trivalent rare-earths (Eu 3+ and Nd 3+ ). In a first part, we have shown by macroscopic experiments (Vickers hardness - swelling) and optical spectroscopies (Raman - ATR-IR) that the structure of the glassy matrices is modified under implantations until a dose of 2,3.10 13 at.cm -2 , which corresponds to a R7T7 storage time estimated at 300 years. Beyond this dose, no additional modifications have been observed. The second part concerns the local environment of the rare-earth ions in glasses. Two different environments were found and identified as follows: one is a silicate rich one and the other is attributed to a borate rich one. (author)

  14. Deep-UV Raman spectroscopic analysis of structure and dissolution rates of silica-rich sodium borosilicate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Windisch, Charles F.; Pierce, Eric M.; Burton, Sarah D.; Bovaird, Chase C.

    2011-03-24

    As part of ongoing studies to evaluate the relationships between structural variations in silicate glasses and rates of glass dissolution in aqueous media, molecular structures present in sodium borosilicate glasses of composition Na2O.xB2O3.(3-x)SiO2, with x 1 (Na2O/B2O3 ratio 1), were analyzed using deep-UV Raman spectroscopy. The results were quantified in terms of the fraction of SiO4 tetrahedra with one non-bridging oxygen (Q3) and then correlated with Na2O and B2O3 content. Increasing Na2O was found to raise the fraction of Q3 units in the glasses systematically, in agreement with studies on related glasses, and, as long as the value of x was not too high, contribute to higher rates of dissolution in single pass flow-through testing. The finding was obtained across more than one series of silica-rich glasses prepared for independent dissolution studies. In contrast, dissolution rates were less strongly determined by the Q3 fraction when the value of x was near unity and appeared to grow larger upon further reduction of the Q3 fraction. The results were interpreted to indicate the increasingly important role of network hydrolysis in the glass dissolution mechanism as the BO4 tetrahedron replaces the Q3 unit as the charge-compensating structure for Na+ ions. Finally, the use of deep-UV Raman spectroscopy was found to be advantageous in studying finely powdered glasses in cases where visible Raman spectroscopy suffered from weak Raman scattering and fluorescence interference.

  15. Conceptual waste package interim product specifications and data requirements for disposal of borosilicate glass defense high-level waste forms in salt geologic repositories

    Energy Technology Data Exchange (ETDEWEB)

    1983-06-01

    The conceptual waste package interim product specifications and data requirements presented are applicable specifically to the normal borosilicate glass product of the Defense Waste Processing Facility (DWPF). They provide preliminary numerical values for the defense high-level waste form parameters and properties identified in the waste form performance specification for geologic isolation in salt repositories. Subject areas treated include containment and isolation, operational period safety, criticality control, waste form/production canister identification, and waste package performance testing requirements. This document was generated for use in the development of conceptual waste package designs in salt. It will be revised as additional data, analyses, and regulatory requirements become available.

  16. Conceptual waste package interim product specifications and data requirements for disposal of borosilicate glass defense high-level waste forms in salt geologic repositories

    International Nuclear Information System (INIS)

    1983-06-01

    The conceptual waste package interim product specifications and data requirements presented are applicable specifically to the normal borosilicate glass product of the Defense Waste Processing Facility (DWPF). They provide preliminary numerical values for the defense high-level waste form parameters and properties identified in the waste form performance specification for geologic isolation in salt repositories. Subject areas treated include containment and isolation, operational period safety, criticality control, waste form/production canister identification, and waste package performance testing requirements. This document was generated for use in the development of conceptual waste package designs in salt. It will be revised as additional data, analyses, and regulatory requirements become available

  17. Calcium-borosilicate glass-ceramics wasteforms to immobilize rare-earth oxide wastes from pyro-processing

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Miae [Department of Materials Science and Engineering and Division of Advanced Nuclear Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 790-784 (Korea, Republic of); Heo, Jong, E-mail: jheo@postech.ac.kr [Department of Materials Science and Engineering and Division of Advanced Nuclear Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 790-784 (Korea, Republic of); Department of Materials Engineering, Adama Science and Technology University (ASTU), PO Box 1888, Adama (Ethiopia)

    2015-12-15

    Glass-ceramics containing calcium neodymium(cerium) oxide silicate [Ca{sub 2}Nd{sub 8-x}Ce{sub x}(SiO{sub 4}){sub 6}O{sub 2}] crystals were fabricated for the immobilization of radioactive wastes that contain large portions of rare-earth ions. Controlled crystallization of alkali borosilicate glasses by heating at T ≥ 750 °C for 3 h formed hexagonal Ca–silicate crystals. Maximum lanthanide oxide waste loading was >26.8 wt.%. Ce and Nd ions were highly partitioned inside Ca–silicate crystals compared to the glass matrix; the rare-earth wastes are efficiently immobilized inside the crystalline phases. The concentrations of Ce and Nd ions released in a material characterization center-type 1 test were below the detection limit (0.1 ppb) of inductively coupled plasma mass spectroscopy. Normalized release values performed by a product consistency test were 2.64·10{sup −6} g m{sup −2} for Ce ion and 2.19·10{sup −6} g m{sup −2} for Nd ion. Results suggest that glass-ceramics containing calcium neodymium(cerium) silicate crystals are good candidate wasteforms for immobilization of lanthanide wastes generated by pyro-processing. - Highlights: • Glass-ceramic wasteforms containing Ca{sub 2}Nd{sub 8-x}Ce{sub x}(SiO{sub 4}){sub 6}O{sub 2} crystals were synthesized to immobilize lanthanide wastes. • Maximum lanthanide oxide waste loading was >26.8 wt.%. • Ce and Nd ions were highly partitioned inside Ca–Nd–silicate crystals compared to glass matrix. • Amounts of Ce and Nd ions released in the material characterization center-type 1 were below the detection limit (0.1 ppb). • Normalized release values performed by a PCT were 2.64• 10{sup −6} g m{sup −2} for Ce ions and 2.19• 10{sup −6} g m{sup −2} for Nd ions.

  18. The structure of phosphate and borosilicate glasses and their structural evolution at high temperatures as studied with solid state NMR spectroscopy: Phase separation, crystallisation and dynamic species exchange

    International Nuclear Information System (INIS)

    Wegner, S.; Van Wullen, L.; Tricot, G.; Tricot, G.

    2010-01-01

    In this contribution we present an in-depth study of the network structure of different phosphate based and borosilicate glasses and its evolution at high temperatures. Employing a range of advanced solid state NMR methodologies, complemented by the results of XPS, the structural motifs on short and intermediate length scales are identified. For the phosphate based glasses, at temperatures above the glass transition temperature Tg, structural relaxation processes and the devitrification of the glasses were monitored in situ employing MAS NMR spectroscopy and X-ray diffraction. Dynamic species exchange involving rapid P-O-P and P-O-Al bond breaking and reforming was observed employing in situ 27 Al and 31 P MAS NMR spectroscopy and could be linked to viscous flow. For the borosilicate glasses, an atomic scale investigation of the phase separation processes was possible in a combined effort of ex situ NMR studies on glass samples with different thermal histories and in situ NMR studies using high temperature MAS NMR spectroscopy including 11 B MAS, 29 Si MAS and in situ 29 Si{ 11 B} REAPDOR NMR spectroscopy. (authors)

  19. Coordination Environments of Highly Charged Cations (Ti, Cr, and Light REE's) in Borosilicate Glass/Melts to 1120C

    Energy Technology Data Exchange (ETDEWEB)

    Farges, Francois; /Museum Natl. Hist. Natur. /Stanford U., Geo. Environ. Sci.; Brown, Gordon E., Jr.; /Stanford U., Geo. Environ Sci. /SLAC, SSRL

    2007-01-02

    The local environments around Ti, Cr, and several light rare-earth elements (La, Ce, and Nd) were investigated by in-situ XANES spectroscopy in a number of complex borosilicate glasses and melts (to 1120 C) that are used for nuclear waste storage. Examination of the high-resolution XANES spectra at the Ti K-edge shows that the average coordination of Ti changes from {approx}5 to {approx}4.5. Cr is dominantly trivalent in the melts studied. However, its average coordination is probably lower in the melt (tetrahedral ?) as revealed by the more intense Cr-K pre-edge feature. Ce also changes its average valence from dominantly +4 to +3.5 upon glass melting. These changes are reversible at T{sub g}, the glass transition temperature ({approx}500-550 C for these glasses). In contrast, the local environments of Nd, Pr, and La are unaffected by melting. Therefore, structural reorganization of these borosilicate glass/melts above T{sub g} is variable, not only in terms of valence (as for Ce) but also speciation (Ti and Cr). Both the ability of B to adopt various coordination geometries (triangular and tetrahedral) and the chemical complexity of the glass/melts explain these changes.

  20. Silicate, borosilicate, and borate bioactive glass scaffolds with controllable degradation rate for bone tissue engineering applications. II. In vitro and in vivo biological evaluation.

    Science.gov (United States)

    Fu, Qiang; Rahaman, Mohamed N; Bal, B Sonny; Bonewald, Lynda F; Kuroki, Keiichi; Brown, Roger F

    2010-10-01

    In Part I, the in vitro degradation of bioactivAR52115e glass scaffolds with a microstructure similar to that of human trabecular bone, but with three different compositions, was investigated as a function of immersion time in a simulated body fluid. The glasses consisted of a silicate (13-93) composition, a borosilicate composition (designated 13-93B1), and a borate composition (13-93B3), in which one-third or all of the SiO2 content of 13-93 was replaced by B2O3, respectively. This work is an extension of Part I, to investigate the effect of the glass composition on the in vitro response of osteogenic MLO-A5 cells to these scaffolds, and on the ability of the scaffolds to support tissue infiltration in a rat subcutaneous implantation model. The results of assays for cell viability and alkaline phosphatase activity showed that the slower degrading silicate 13-93 and borosilicate 13-93B1 scaffolds were far better than the borate 13-93B3 scaffolds in supporting cell proliferation and function. However, all three groups of scaffolds showed the ability to support tissue infiltration in vivo after implantation for 6 weeks. The results indicate that the required bioactivity and degradation rate may be achieved by substituting an appropriate amount of SiO2 in 13-93 glass with B2O3, and that these trabecular glass scaffolds could serve as substrates for the repair and regeneration of contained bone defects. Copyright 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.

  1. A critical study on borosilicate glassware and silica-based QMA's in nucleophilic substitution with [18F]fluoride: influence of aluminum, boron and silicon on the reactivity of [18F]fluoride.

    Science.gov (United States)

    Svadberg, A; Clarke, A; Dyrstad, K; Martinsen, I; Hjelstuen, O K

    2011-02-01

    Leachables of borosilicate glassware and silica-based anion exchange columns (QMAs) may influence nucleophilic substitution with [(18)F]fluoride ([(18)F]F(-)). Aluminum, boron and silicon, all constituents of borosilicate glass, were found as water soluble leachables in a typical PET synthesis setup. Relevant ranges of the leachable quantities were studied based on an experimental design, in which species of the three elements were added to the labeling of the precursor for anti-1-amino-3-[(18)F]fluorocyclobutyl-1-carboxylic acid ([(18)F]FACBC). Levels of 0.4-2 ppm aluminum as AlCl(3) had a strong negative influence on labeling yield while 4-20 ppm of boron as KBO(2) and 50-250 ppm of silicon as Na(2)SiO(3) did not have a significant impact. Interesting interaction effects between the elements were observed, where particularly KBO(2) reduced the negative effect of AlCl(3) on labeling yield. It can be concluded that leachables of borosilicate glassware easily can influence nucleophilic substitution with n.c.a. [(18)F]F(-) and give variable yields. Copyright © 2010. Published by Elsevier Ltd.

  2. A critical study on borosilicate glassware and silica-based QMA's in nucleophilic substitution with [{sup 18}F]fluoride: influence of aluminum, boron and silicon on the reactivity of [{sup 18}F]fluoride

    Energy Technology Data Exchange (ETDEWEB)

    Svadberg, A., E-mail: anders.svadberg@uit.n [University of Tromso, Institute of Pharmacy, Department of Pharmaceutics and Biopharmaceutics, N-9037 Tromso (Norway); Clarke, A.; Dyrstad, K.; Martinsen, I. [GE Healthcare MDx R and D, Nycoveien 2, NO-0401 Oslo (Norway); Hjelstuen, O.K. [University of Tromso, Institute of Pharmacy, Department of Pharmaceutics and Biopharmaceutics, N-9037 Tromso (Norway); GE Healthcare MDx R and D, Nycoveien 2, NO-0401 Oslo (Norway)

    2011-02-15

    Leachables of borosilicate glassware and silica-based anion exchange columns (QMAs) may influence nucleophilic substitution with [{sup 18}F]fluoride ([{sup 18}F]F{sup -}). Aluminum, boron and silicon, all constituents of borosilicate glass, were found as water soluble leachables in a typical PET synthesis setup. Relevant ranges of the leachable quantities were studied based on an experimental design, in which species of the three elements were added to the labeling of the precursor for anti-1-amino-3-[{sup 18}F]fluorocyclobutyl-1-carboxylic acid ([{sup 18}F]FACBC). Levels of 0.4-2 ppm aluminum as AlCl{sub 3} had a strong negative influence on labeling yield while 4-20 ppm of boron as KBO{sub 2} and 50-250 ppm of silicon as Na{sub 2}SiO{sub 3} did not have a significant impact. Interesting interaction effects between the elements were observed, where particularly KBO{sub 2} reduced the negative effect of AlCl{sub 3} on labeling yield. It can be concluded that leachables of borosilicate glassware easily can influence nucleophilic substitution with n.c.a. [{sup 18}F]F{sup -} and give variable yields.

  3. Lanthanide-activated Na5Gd9F32 nanocrystals precipitated from a borosilicate glass: Phase-separation-controlled crystallization and optical property

    International Nuclear Information System (INIS)

    Chen, Daqin; Wan, Zhongyi; Zhou, Yang; Chen, Yan; Yu, Hua; Lu, Hongwei; Ji, Zhenguo; Huang, Ping

    2015-01-01

    Highlights: • Na 5 Gd 9 F 32 nanocrystals embedded glass ceramics were fabricated for the first time. • Such glass ceramics were achieved by phase-separation-controlled crystallization. • Elemental mapping evidenced the segregation of activators into the Na 5 Gd 9 F 32 lattice. • Luminescent color could be tuned by controlling glass crystallization temperature. - Abstract: Lanthanide-activated cubic Na 5 Gd 9 F 32 nanocrystals were precipitated from a borosilicate glass with a specifically designed composition. The precursor glass is already phase-separated after melt-quenching, which is beneficial to the realization of the controllable glass crystallization for affording desirable size, morphology and activator partition. Elemental mapping in the scanning transmission electron microscopy evidenced that the segregation of lanthanide ions into the Na 5 Gd 9 F 32 lattice was in situ formed without the requirement of long-range ionic diffusion. Impressively, such fabricated glass ceramic co-doped with Yb 3+ /Er 3+ ions exhibited intense upconversion luminescence, which was about 500 times higher than that of the precursor glass, and its luminescent color could be easily tuned from red to green by controlling glass crystallization temperature. It is anticipated that such phase-separation synthesis strategy with precise control over nanostructure of glass ceramics offer a great opportunity to design other highly transparent nanocomposites with a wide range of tunable optical properties

  4. A Comparison of Modifications Induced by Li3+ and Ag14+ Ion Beam in Spectroscopic Properties of Bismuth Alumino-Borosilicate Glass Thin Films

    Directory of Open Access Journals (Sweden)

    Ravneet Kaur

    2013-01-01

    Full Text Available Ion irradiation effects on the glass network and structural units have been studied by irradiating borosilicate glass thin film samples with 50 MeV Li3+ and 180 MeV Ag14+ swift heavy ions (SHI at different fluence rates ranging from 1012 ions/cm2 to 1014 ions/cm2. Glass of the composition (65-x Bi2O3-10Al2O3-(65-y B2O3-25SiO2 (x = 45, 40; y = 20, 25 has been prepared by melt quench technique. To study the effects of ionizing radiation, the glass thin films have been prepared from these glasses and characterized using XRD, FTIR, and UV-Vis spectroscopic techniques. IR spectra are used to study the structural arrangements in the glass before and after irradiation. The values of optical band gap, Urbach energy, and refractive index have been calculated from the UV-Vis measurements. The variation in optical parameters with increasing Bi2O3 content has been analyzed and discussed in terms of changes occurring in the glass network. A comparative study of the influence of Li3+ ion beam on structural and optical properties of the either glass system with Ag14+ ion is done. The results have been explained in the light of the interaction that SHI undergo on entering the material.

  5. Silver diffusion and coloration of soda lime and borosilicate glasses, Part 1: Effect on the transmission and coloration of stained glasses

    Directory of Open Access Journals (Sweden)

    ABDELLAH CHORFA

    2012-03-01

    Full Text Available Using the conventional method of coloration, soda lime and borosilicate glasses have been painted. Once stained, these glasses were heat treated at temperatures close to their transition temperatures (Tg. A parametric study was carried out in order to determine at first the effect of the silver concentration in the stain spread on glass. In addition, it was studied the effect of the heat treatment duration and the chemical composition of the painted glasses on the formation and size of the silver nanoparticles, the silver diffusion depth and also the glasses coloration. The characterization was made using UV-Vis spectroscopy, Raman confocal spectroscopy, SEM, EDX Technique and Abbe Refractometer. The obtained results shows that the coloration intensity of both glass types painted by the conventional method differs and depends essentially on the proportion of alkali ions in the glass. Moreover, it was found that the effect of the silver concentration in the stain is primordial and the heat treatment duration has a limited effect.

  6. Effect of {sup 10}B(n, α){sup 7}Li irradiation on the structure of a sodium borosilicate glass

    Energy Technology Data Exchange (ETDEWEB)

    Peuget, S., E-mail: sylvain.peuget@cea.fr [CEA, DEN, Laboratoire d’Étude des Matériaux et Procédés Actif, 30207 Bagnols-sur-Cèze (France); Fares, T.; Maugeri, E.A.; Caraballo, R. [CEA, DEN, Laboratoire d’Étude des Matériaux et Procédés Actif, 30207 Bagnols-sur-Cèze (France); Charpentier, T. [CEA, IRAMIS, SIS2M, Laboratoire de Structure et Dynamique par Résonance Magnétique, UMR CEA/CNRS 3299, 91191 Gif-sur-Yvette (France); Martel, L.; Somers, J.; Janssen, A.; Wiss, T. [European Commission, JRC, Institute for Transuranium Elements (ITU), Hermann-von-Helmholtz Platz 1, PO Box 2340, DE-76125 Karlsruhe (Germany); Rozenblum, F. [CEA, DEN, DANS/DRSN/SIREN/LECSI, 91191 Gif-sur-Yvette (France); Magnin, M. [CEA, DEN, Laboratoire d’Étude des Matériaux et Procédés Actif, 30207 Bagnols-sur-Cèze (France); Deschanels, X. [Marcoule Institute of Separation Chemistry, LNAR, 30207 Bagnols-sur-Cèze Cedex (France); Jégou, C. [CEA, DEN, Laboratoire d’Étude des Matériaux et Procédés Actif, 30207 Bagnols-sur-Cèze (France)

    2014-05-01

    The effects of the nuclear reaction {sup 10}B(n, α){sup 7}Li on the properties and structure of a sodium borosilicate glass were analysed by density, hardness and fracture toughness measurements, Raman and Nuclear Magnetic Resonance spectroscopy and Transmission Electronic Microscopy (TEM) characterization. The TEM observations showed a homogeneous irradiated glass structure up to the nanometer scale. Modifications of the local order around the main cations were noticed, mainly a slight decrease of the mean boron coordination number and an increase of non-bridging oxygen concentrations. At the glass medium range order, the appearance of the D2 Raman band and a modification of the Si–O–Si angle distribution were also observed after irradiation. A comparison with other irradiation conditions with Swift Heavy Ions (Kr with 74 MeV) and Gold irradiation (with energies ranging from 1 to 7 MeV) is presented. Raman spectroscopy showed a similar final structure for irradiation conditions under which the glass evolutions are controlled by electronic energy loss in the ion tracks formation regime or nuclear energy loss. Despite important differences in energy deposition regimes, the similarities observed between the final glass structures suggest that structural evolutions are controlled by the glass relaxation mechanisms during the high quenching rate step that follows the energy deposition step.

  7. Crystalline phase, microstructure, and aqueous stability of zirconolite-barium borosilicate glass-ceramics for immobilization of simulated sulfate bearing high-level liquid waste

    Science.gov (United States)

    Wu, Lang; Xiao, Jizong; Wang, Xin; Teng, Yuancheng; Li, Yuxiang; Liao, Qilong

    2018-01-01

    The crystalline phase, microstructure, and aqueous stability of zirconolite-barium borosilicate glass-ceramics with different content (0-30 wt %) of simulated sulfate bearing high-level liquid waste (HLLW) were evaluated. The sulfate phase segregation in vitrification process was also investigated. The results show that the glass-ceramics with 0-20 wt% of HLLW possess mainly zirconolite phase along with a small amount baddeleyite phase. The amount of perovskite crystals increases while the amount of zirconolite crystals decreases when the HLLW content increases from 20 to 30 wt%. For the samples with 20-30 wt% HLLW, yellow phase was observed during the vitrification process and it disappeared after melting at 1150 °C for 2 h. The viscosity of the sample with 16 wt% HLLW (HLLW-16) is about 27 dPa·s at 1150 °C. The addition of a certain amount (≤20 wt %) of HLLW has no significant change on the aqueous stability of glass-ceramic waste forms. After 28 days, the 90 °C PCT-type normalized leaching rates of Na, B, Si, and La of the sample HLLW-16 are 7.23 × 10-3, 1.57 × 10-3, 8.06 × 10-4, and 1.23 × 10-4 g·m-2·d-1, respectively.

  8. Silicate, borosilicate, and borate bioactive glass scaffolds with controllable degradation rate for bone tissue engineering applications. I. Preparation and in vitro degradation.

    Science.gov (United States)

    Fu, Qiang; Rahaman, Mohamed N; Fu, Hailuo; Liu, Xin

    2010-10-01

    Bioactive glass scaffolds with a microstructure similar to that of dry human trabecular bone but with three different compositions were evaluated for potential applications in bone repair. The preparation of the scaffolds and the effect of the glass composition on the degradation and conversion of the scaffolds to a hydroxyapatite (HA)-type material in a simulated body fluid (SBF) are reported here (Part I). The in vitro response of osteogenic cells to the scaffolds and the in vivo evaluation of the scaffolds in a rat subcutaneous implantation model are described in Part II. Scaffolds (porosity = 78-82%; pore size = 100-500 microm) were prepared using a polymer foam replication technique. The glasses consisted of a silicate (13-93) composition, a borosilicate composition (designated 13-93B1), and a borate composition (13-93B3), in which one-third or all of the SiO2 content of 13-93 was replaced by B2O3, respectively. The conversion rate of the scaffolds to HA in the SBF increased markedly with the B2O3 content of the glass. Concurrently, the pH of the SBF also increased with the B2O3 content of the scaffolds. The compressive strengths of the as-prepared scaffolds (5-11 MPa) were in the upper range of values reported for trabecular bone, but they decreased markedly with immersion time in the SBF and with increasing B2O3 content of the glass. The results show that scaffolds with a wide range of bioactivity and degradation rate can be achieved by replacing varying amounts of SiO(2) in silicate bioactive glass with B2O3. Copyright 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.

  9. NMR study of a rare-earth alumino-borosilicate glass with varying CaO-to-Na{sub 2}O ratio

    Energy Technology Data Exchange (ETDEWEB)

    Quintas, A.; Majerus, O.; Caurant, D. [Ecole Natl Super Chim Paris, Lab Chim Mat Condensee Paris, F-75231 Paris 05 (France); Quintas, A.; Dussossoy, J.L. [Commissariat Energie Atom Marcoule, Lab Etudes Base Verres, Bagnols Sur Ceze (France); Charpentier, T. [Commissariat Energie Atom Saclay, Lab Struct and Dynam Responance Magnet, Gif Sur Yvette (France); Vermaut, P. [Ecole Natl Super Chim Paris, Lab Met Struct, F-75231 Paris, (France)

    2007-12-15

    The effect of substituting two Na{sup +} by one Ca{sup 2+} in a rare-earth alumino-borosilicate glass is investigated by multinuclear magic-angle spinning (MAS) and multiple-quantum (MQ)MAS nuclear magnetic resonance (NMR) spectroscopy. Quantitative analysis of the {sup 23}Na and {sup 27}Al MAS/MQMAS data along with the {sup 11}B MAS NMR data provides complementary information enabling to cast light on different structural key points. A strong decrease of the N{sub 4} = BO{sub 4}/(BO{sub 3} + BO{sub 4}) ratio is observed consecutively to this substitution, indicating that sodium is more favorable than calcium to the formation of BO{sub 4} units. The experimental N{sub 4} ratio is compared to the Dell and Bray model prediction and it is shown that several adjustments, due to the presence in our glass of Nd and Zr, are necessary to obtain acceptable agreement with experimental data. {sup 29}Si MAS NMR data also put in evidence an effect of the substitution on the polymerization degree. Glass in glass phase separation is clearly detected when the ratio of CaO to Na{sub 2}O is greater than 1 and a different evolution of NMR parameters is observed for the ratio of CaO to Na{sub 2}O being less than or equal to 1. Concerning aluminum charge compensation, it is demonstrated that, as long as no phase separation is detected, the negative charge of AlO{sub 4}{sup -} entities is almost exclusively balanced by sodium cations. Finally, changes of the sodium ions organization within the glass network are also evidenced by spin-lattice relaxation and spin echo decay measurements. (authors)

  10. Irradiations effects on the structure of boro-silicated glasses: long term behaviour of nuclear waste glassy matrices; Effets d'irradiations sur la structure de verres borosilicates - comportement a long terme des matrices vitreuses de stockage des dechets nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Bonfils, J. de

    2007-09-15

    This work deals with the long term behaviour of R7T7-type nuclear waste glasses and more particularly of non-active boro-silicated glasses made up of 3 or 5 oxides. Radioactivity of active glasses is simulated by multi energies ions implantations which reproduce the same defects. The damages due to the alpha particles are simulated by helium ions implantations and those corresponding to the recoil nucleus are obtained with gold ions ones. Minor actinides, stemming from the used fuel, is simulated by trivalent rare-earths (Eu{sup 3+} and Nd{sup 3+}). In a first part, we have shown by macroscopic experiments (Vickers hardness - swelling) and optical spectroscopies (Raman - ATR-IR) that the structure of the glassy matrices is modified under implantations until a dose of 2,3.10{sup 13} at.cm{sup -2}, which corresponds to a R7T7 storage time estimated at 300 years. Beyond this dose, no additional modifications have been observed. The second part concerns the local environment of the rare-earth ions in glasses. Two different environments were found and identified as follows: one is a silicate rich one and the other is attributed to a borate rich one. (author)

  11. β-Irradiation Effects on the Formation and Stability of CaMoO4 in a Soda Lime Borosilicate Glass Ceramic for Nuclear Waste Storage.

    Science.gov (United States)

    Patel, Karishma B; Boizot, Bruno; Facq, Sébastien P; Lampronti, Giulio I; Peuget, Sylvain; Schuller, Sophie; Farnan, Ian

    2017-02-06

    Molybdenum solubility is a limiting factor to actinide loading in nuclear waste glasses, as it initiates the formation of water-soluble crystalline phases such as alkali molybdates. To increase waste loading efficiency, alternative glass ceramic structures are sought that prove resistant to internal radiation resulting from radioisotope decay. In this study, selective formation of water-durable CaMoO 4 in a soda lime borosilicate is achieved by introducing up to 10 mol % MoO 3 in a 1:1 ratio to CaO using a sintering process. The resulting homogeneously dispersed spherical CaMoO 4 nanocrystallites were analyzed using electron microscopy, X-ray diffraction (XRD), Raman and electron paramagnetic resonance (EPR) spectroscopies prior to and post irradiation, which replicated internal β-irradiation damage on an accelerated scale. Following 0.77 to 1.34 GGy of 2.5 MeV electron radiation CaMoO 4 does not exhibit amorphization or significant transformation. Nor does irradiation induce glass-in-glass phase separation in the surrounding amorphous matrix, or the precipitation of other molybdates, thus proving that excess molybdenum can be successfully incorporated into a structure that it is resistant to β-irradiation proportional to 1000 years of storage without water-soluble byproducts. The CaMoO 4 crystallites do however exhibit a nonlinear Scherrer crystallite size pattern with dose, as determined by a Rietveld refinement of XRD patterns and an alteration in crystal quality as deduced by anisotropic peak changes in both XRD and Raman spectroscopy. Radiation-induced modifications in the CaMoO 4 tetragonal unit cell occurred primarily along the c-axis indicating relaxation of stacked calcium polyhedra. Concurrently, a strong reduction of Mo 6+ to Mo 5+ during irradiation is observed by EPR, which is believed to enhance Ca mobility. These combined results are used to hypothesize a crystallite size alteration model based on a combination of relaxation and diffusion

  12. Structure-composition trends in multicomponent borosilicate-based glasses deduced from molecular dynamics simulations with improved B-O and P-O force fields.

    Science.gov (United States)

    Stevensson, Baltzar; Yu, Yang; Edén, Mattias

    2018-03-28

    We present a comprehensive molecular dynamics (MD) simulation study of composition-structure trends in a set of 25 glasses of widely spanning compositions from the following four systems of increasing complexity: Na 2 O-B 2 O 3 , Na 2 O-B 2 O 3 -SiO 2 , Na 2 O-CaO-SiO 2 -P 2 O 5 , and Na 2 O-CaO-B 2 O 3 -SiO 2 -P 2 O 5 . The simulations involved new B-O and P-O potential parameters developed within the polarizable shell-model framework, thereby combining the beneficial features of an overall high accuracy and excellent transferability among different glass systems and compositions: this was confirmed by the good accordance with experimental data on the relative BO 3 /BO 4 populations in borate and boro(phospho)silicate networks, as well as with the orthophosphate fractions in bioactive (boro)phosphosilicate glasses, which is believed to strongly influence their bone-bonding properties. The bearing of the simulated melt-cooling rate on the borate/phosphate speciations is discussed. Each local {BO 3 , BO 4 , SiO 4 , PO 4 } coordination environment remained independent of the precise set of co-existing network formers, while all trends observed in bond-lengths/angles mainly reflected the glass-network polymerization, i.e., the relative amounts of bridging oxygen (BO) and non-bridging oxygen (NBO) species. The structural roles of the Na + /Ca 2+ cations were also probed, targeting their local coordination environments and their relative preferences to associate with the various borate, silicate, and phosphate moieties. We evaluate and discuss the common classification of alkali/alkaline-earth metal ions as charge-compensators of either BO 4 tetrahedra or NBO anions in borosilicate glasses, also encompassing the less explored NBO-rich regime: the Na + /Ca 2+ cations mainly associate with BO/NBO species of SiO 4 /BO 3 groups, with significant relative Na-BO 4 contacts only observed in B-rich glass networks devoid of NBO species, whereas NBO-rich glass networks also

  13. Mineralogical textural and compositional data on the alteration of basaltic glass from Kilauea, Hawaii to 300 degrees C: Insights to the corrosion of a borosilicate glass waste-form

    International Nuclear Information System (INIS)

    Smith, D.K.

    1990-01-01

    Mineralogical, textural and compositional data accompanying greenschist facies metamorphism (to 300 degrees C) of basalts of the East Rift Zone (ERZ), Kilauea, Hawaii may be evaluated relative to published and experimental results for the surface corrosion of borosilicate glass. The ERZ alteration sequence is dominated by intermittent palagonite, interlayered smectite-chlorite, chlorite, and actinolite-epidote-anhydrite. Alteration is best developed in fractures and vesicles where surface reaction layers root on the glass matrix forming rinds in excess of 100 microns thick. Fractures control fluid circulation and the alteration sequence. Proximal to the glass surface, palagonite, Fe-Ti oxides and clays replace fresh glass as the surface reaction layer migrates inwards; away from the surface, amphibole, anhydrite, quartz and calcite crystallize from hydrothermal fluids in contact with the glass. The texture and composition of basaltic glass surfaces are similar to those of a SRL-165 glass leached statically for sixty days at 150 degrees C. While the ERZ reservoir is a complex open system, conservative comparisons between the alteration of ERZ and synthetic borosilicate glass are warranted. 31 refs., 2 figs

  14. Effect of the nature of alkali and alkaline-earth oxides on the structure and crystallization of an alumino-borosilicate glass developed to immobilize highly concentrated nuclear waste solutions

    International Nuclear Information System (INIS)

    Quintas, A.; Caurant, D.; Majerus, O.; Charpentier, T.; Dussossoy, J.L.

    2008-01-01

    A complex rare-earth rich alumino-borosilicate glass has been proved to be a good candidate for the immobilization of new high level radioactive wastes. A simplified seven-oxides composition of this glass was selected for this study. In this system, sodium and calcium cations were supposed in other works to simulate respectively all the other alkali (R + = Li + , Rb + , Cs + ) and alkaline-earth (R 2+ = Sr 2+ , Ba 2+ ) cations present in the complex glass composition. Moreover, neodymium or lanthanum are used here to simulate all the rare-earths and actinides occurring in waste solutions. In order to study the impact of the nature of R + and R 2+ cations on both glass structure and melt crystallization tendency during cooling, two glass series were prepared by replacing either Na + or Ca 2+ cations in the simplified glass by respectively (Li + , K + , Rb + , Cs + ) or (Mg 2+ , Sr 2+ , Ba 2+ ) cations. From these substitutions, it was established that alkali ions are preferentially involved in the charge compensation of (AlO 4 ) - entities in the glass network comparatively to alkaline-earth ions. The glass compositions containing calcium give way to the crystallization of an apatite silicate phase bearing calcium and rare-earth ions. The melt crystallization tendency during cooling strongly varies with the nature of the alkaline-earth. (authors)

  15. Effect of the nature of alkali and alkaline-earth oxides on the structure and crystallization of an alumino-borosilicate glass developed to immobilize highly concentrated nuclear waste solutions

    Energy Technology Data Exchange (ETDEWEB)

    Quintas, A.; Caurant, D.; Majerus, O. [Laboratoire de Chimie de la Matiere Condensee de Paris (UMR 7574), Ecole Nationale Superieure de Chimie de Paris - ENSCP, ParisTech, Paris, 75005 (France); Charpentier, T. [CEA Saclay, Laboratoire de Structure et Dynamique par Resonance Magnetique, DSM/DRECAM/SCM - CEA CNRS URA 331, Gif-sur-Yvette, 91191 (France); Dussossoy, J.L. [Laboratoire d' Etude de Base sur les Verres, CEA Valrho, DEN/DTCD/SCDV/LEBV, Bagnols-sur-Ceze, 30207 (France)

    2008-07-01

    A complex rare-earth rich alumino-borosilicate glass has been proved to be a good candidate for the immobilization of new high level radioactive wastes. A simplified seven-oxides composition of this glass was selected for this study. In this system, sodium and calcium cations were supposed in other works to simulate respectively all the other alkali (R{sup +} = Li{sup +}, Rb{sup +}, Cs{sup +}) and alkaline-earth (R{sup 2+} = Sr{sup 2+}, Ba{sup 2+}) cations present in the complex glass composition. Moreover, neodymium or lanthanum are used here to simulate all the rare-earths and actinides occurring in waste solutions. In order to study the impact of the nature of R{sup +} and R{sup 2+} cations on both glass structure and melt crystallization tendency during cooling, two glass series were prepared by replacing either Na{sup +} or Ca{sup 2+} cations in the simplified glass by respectively (Li{sup +}, K{sup +}, Rb{sup +}, Cs{sup +}) or (Mg{sup 2+}, Sr{sup 2+}, Ba{sup 2+}) cations. From these substitutions, it was established that alkali ions are preferentially involved in the charge compensation of (AlO{sub 4}){sup -} entities in the glass network comparatively to alkaline-earth ions. The glass compositions containing calcium give way to the crystallization of an apatite silicate phase bearing calcium and rare-earth ions. The melt crystallization tendency during cooling strongly varies with the nature of the alkaline-earth. (authors)

  16. Influence of P{sub 2}O{sub 5} and Al{sub 2}O{sub 3} content on the structure of erbium-doped borosilicate glasses and on their physical, thermal, optical and luminescence properties

    Energy Technology Data Exchange (ETDEWEB)

    Bourhis, Kevin, E-mail: k.bourhis@argolight.com [Politecnico di Torino, DISAT, Istituto di Ingegneria e Fisica dei Materiali, Corso Duca degli Abruzzi 24, I-10129 Torino (Italy); Massera, Jonathan [Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Turku (Finland); Petit, Laeticia; Ihalainen, Heikki [nLIGHT Corporation, Sorronrinne 9, FI-08500 Lohja (Finland); Fargues, Alexandre; Cardinal, Thierry [CNRS, Université de Bordeaux, ISM, 351Cours de la Libération, F-33405 Talence (France); Hupa, Leena; Hupa, Mikko [Process Chemistry Centre, Åbo Akademi University, Biskopsgatan 8, FI-20500 Turku (Finland); Dussauze, Marc; Rodriguez, Vincent [CNRS, Université de Bordeaux, ICMCB, 87 Avenue du Dr Schweitzer, F-33608 Pessac (France); Boussard-Plédel, Catherine; Bureau, Bruno; Roiland, Claire [Equipe Verres et Céramiques, UMR-CNRS 6226, Inst. des Sciences chimiques de Rennes, Université de Rennes 1, 35042 Rennes CEDEX (France); Ferraris, Monica [Politecnico di Torino, DISAT, Istituto di Ingegneria e Fisica dei Materiali, Corso Duca degli Abruzzi 24, I-10129 Torino (Italy)

    2015-03-15

    Highlights: • Reorganization of the glass structure induced by the addition of P{sub 2}O{sub 5} or Al{sub 2}O{sub 3}. • Emission properties related to the presence of P or Al in the Er{sup 3+} coordination shell. • Declustering observed upon addition of P{sub 2}O{sub 5}. • No declustering upon addition of Al{sub 2}O{sub 3}. - Abstract: The effect of P{sub 2}O{sub 5} and/or Al{sub 2}O{sub 3} addition in Er-doped borosilicate glasses on the physical, thermal, optical, and luminescence properties is investigated. The changes in these glass properties are related to the glass structure modifications induced by the addition of P{sub 2}O{sub 5} and/or Al{sub 2}O{sub 3}, which were probed by FTIR, {sup 11}B MAS NMR and X-ray photoelectron spectroscopies. Variations of the polymerization degree of the silicate tetrahedra and modifications in the {sup [3]}B/{sup [4]}B ratio are explained by a charge compensation mechanism due to the formation of AlO{sub 4}, PO{sub 4} groups and the formation of Al-O-P linkages in the glass network. From the absorption and luminescence properties of the Er{sup 3+} ions at 980 nm and 1530 nm, declustering is suspected for the highest P{sub 2}O{sub 5} concentrations while for the highest Al{sub 2}O{sub 3} concentrations no declustering is observed.

  17. Structural and crystallisation study of a rare earth alumino borosilicate glass designed for nuclear waste confinement; Etude de la structure et du comportement en cristallisation d'un verre nucleaire d'aluminoborosilicate de terre rare

    Energy Technology Data Exchange (ETDEWEB)

    Quintas, A

    2007-09-15

    This work is devoted to the study of a rare earth alumino borosilicate glass, which molar composition is 61,81 SiO{sub 2} - 3,05 Al{sub 2}O{sub 3} - 8,94 B{sub 2}O{sub 3} - 14,41 Na{sub 2}O - 6,33 CaO - 1,90 ZrO{sub 2} - 3,56 Nd{sub 2}O{sub 3}, and envisaged for the immobilization of nuclear wastes originating from the reprocessing of high discharge burn up spent fuel. From a structural viewpoint, we investigated the role of the modifier cations on the arrangement of the glass network through different modifications of the glass composition: variation of the Na/Ca ratio and modification of the nature of the alkali and alkaline earth cations. The NMR and Raman spectroscopic techniques were useful to determine the distribution of modifier cations among the glass network and also to cast light on the competition phenomena occurring between alkali and alkaline earth cations for charge compensation of [AlO{sub 4}]{sup -} and [BO{sub 4}]{sup -} species. The neodymium local environment could be probed by optical absorption and EXAFS spectroscopies which enabled to better understand the insertion mode of Nd{sup 3+} ions among the silicate domains of the glass network. Concerning the crystallization behavior we were interested in how the glass composition may influence the crystallization processes and especially the formation of the apatite phase of composition Ca{sub 2}Nd{sub 8}(SiO{sub 4}){sub 6}O{sub 2}. In particular, this work underlined the important role of both alkaline earth and rare earth cations on the crystallization of the apatite phase. (author)

  18. XRD and DSC study of the formation and the melting of a new zeolite like borosilicate CsBSi5O12 and (Cs,Rb)BSi5O12 solid solutions

    International Nuclear Information System (INIS)

    Bubnova, R.S.; Ugolkov, V.L.; Krzhizhanovskaya, M.G.; Filatov, S.K.; Paufler, P.

    2007-01-01

    Polycrystalline CsBSi 5 O 12 was prepared from a stoichiometric mixture by solid-state reaction above 1000 C. The solid solutions Cs 1-x Rb x BSi 5 O 12 were obtained at 1000 C during a long heat treatment of polycrystalline Cs 1-x Rb x BSi 2 O 6 boropollucites (x Rb = 0, 0.05, 0.2, 0.4). A new borosilicate compound and its solid solutions were studied using X-ray powder diffraction (XRD), annealing, differential scanning calorimetry (DSC), and thermogravimetry (TG). For Cs,Rb-boropollucites the new phase formation is accompanied by significant mass losses detected by DSC and TG. The following mechanism of phase transformations is assumed: (Cs,Rb)BSi 2 O 6 → (Cs,Rb)BSi 5 O 12 + (Cs,Rb)BO 2 ↑. The zeolite phase forms as a result of the boropollucite decomposition over 1000 C. Zeolite decomposes also on further heating and the SiO 2 reflections are observed in the XRD pattern only. Thus above 1000 C both boropollucite and zeolite phases are unstable presumably due to the ability of the alkali cations to leave the structure. Using XRD the unit cell parameters of CsBSi 5 O 12 have been determined in the orthorhombic crystal system: a = 16.242(4) A, b = 13.360(4) A, c = 4.874(1) A. The compound is isostructural with the zeolite compound CsAlSi 5 O 12 . In the crystal structure of Cs 1-x Rb x BSi 5 O 12 solid solutions the changes of cell parameters are insignificant under the substitution of Cs by Rb atoms that indicates a very limited substitution range. (orig.)

  19. Simulating the physicochemical properties of borosilicate and lanthanum borosilicate glasses using a polarizable force field

    International Nuclear Information System (INIS)

    Pacaud, Fabien

    2016-01-01

    as result of the nuclear waste vitrification, the knowledge and understanding of the dynamic and structural properties of glasses, including the behavior of radionuclides, is important (in liquid and solid phases). It can influence the glass waste properties, the lifetime of the vitrification process and the amount of radionuclides introduced in the glass matrix. Molecular dynamic simulations have been done to study the influence of the glass matrix composition into the structural and dynamic properties of the glass. a simplified glass, with 3 major oxides of the R7T7 glass such as SiO 2 , B 2 O 3 and Na 2 O, have been used to simulate the R7T7 industrial nuclear glass (a 30 oxides glass). The inclusion of La 2 O 3 allows us to simulate the impact of fission products and minor actinides into the properties of the glass matrix. Both systems, the SiO 2 -B 2 O 3 -Na 2 O and SiO 2 -B 2 O 3 -Na 2 O-La 2 O 3 , allow us to study the sodium and lanthanum effect on the properties of the glass. During this work, a polarizable force field has been developed to do these simulations. The results obtained at room temperature let us reproduce the experimental results of the structure, the distribution of BIII/BIV and the density. a study has been done on the viscosity and electrical conductivity of the liquid. The distribution BIV/BIII and the influence of the structural changes on the density along with the temperature have also been observed with thermal quenching. The current limits of this approach are also described. (author) [fr

  20. Effect of Gd2O3 doping on structure and boron volatility of borosilicate glass sealants in solid oxide fuel cells-A study on the La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathode

    Science.gov (United States)

    Zhang, Qi; Tan, Shengwei; Ren, Mengyuan; Yang, Hsiwen; Tang, Dian; Chen, Kongfa; Zhang, Teng; Jiang, San Ping

    2018-04-01

    Boron volatility is one of the most important properties of borosilicate-based glass sealants in solid oxide fuel cells (SOFCs), as boron contaminants react with lanthanum-containing cathodes, forming LaBO3 and degrading the activity of SOFCs. Here, we report that the reaction between the volatile boron and a La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathode during polarization can be significantly reduced by doping aluminoborosilicate glass with Gd2O3. Specifically, the Gd cations in glass with 2 mol.% Gd2O3 dissolve preferentially in the borate-rich environment to form more Gd-metaborate structures and promote the formation of calcium metaborate (CaB2O4); they also condense the B-O network after heat treatment, which suppresses poisoning by boron contaminants on the LSCF cathode. The results provide insights into design and development of a reliable sealing glass for SOFC applications.

  1. Chemical compatibility of HLW borosilicate glasses with actinides

    International Nuclear Information System (INIS)

    Walker, C.T.; Scheffler, K.; Riege, U.

    1978-11-01

    During liquid storage of HLLW the formation of actinide enriched sludges is being expected. Also during melting of HLW glasses an increase of top-to-bottom actinide concentrations can take place. Both effects have been studied. Besides, the vitrification of plutonium enriched wastes from Pu fuel element fabrication plants has been investigated with respect to an isolated vitrification process or a combined one with the HLLW. It is shown that the solidification of actinides from HLLW and actinide waste concentrates will set no principal problems. The leaching of actinides has been measured in salt brine at 23 0 C and 115 0 C. (orig.) [de

  2. IR study of Pb–Sr titanate borosilicate glasses

    Indian Academy of Sciences (India)

    Administrator

    to study their structure systematically. IR spectrum of each glass composition shows a number of absorption bands. These bands are strongly influenced by the increasing substitution of SrO for PbO. Various bands shift with composition. Absorption peaks occur due to the vibrational mode of the borate network in these ...

  3. Ultrasonic and structural features of some borosilicate glasses ...

    Indian Academy of Sciences (India)

    Therefore, the glass structure becomes contractedand compacted, which decreases its molar volume and increases its rigidity. This concept was asserted from the increase in the ultrasonic velocity, Debye temperature and elastic moduli with the increase of SiO2 content. The present compositional dependence of the elastic ...

  4. Borosilicate glasses for the high activity waste vetrification

    International Nuclear Information System (INIS)

    Cantale, C.; Donato, A.; Guidi, G.

    1984-01-01

    Some results concerning the researches carried out on the high-level wastes vitrification at ENEA, Comb-Mepis-Rifiu laboratory are reported. A fission product solution referred to power plant nuclear fuel reprocessing has been selected and simulated with no radioactive chemicals. Some glass composition have been tested for the vitrification of this solution, the best of them being taken into consideration for real active tests at the hot bench scale plant ESTER in Ispra. The final glasses have been characterized from the chemical and physical point of view; moreover some microstructural investigations have been performed in order to identify few microsegregations and to test the degree of amorphousness of the products

  5. Effect of Radiation on Silicon and Borosilicate Glass

    National Research Council Canada - National Science Library

    Allred, Clark

    2003-01-01

    .... These two glasses are commonly used as substrates for silicon microelectromechanical (MEMS) devices, and radiation-induced compaction in a substrate can have deleterious effects on device performance...

  6. PLUTONIUM SOLUBILITY IN HIGH-LEVEL WASTE ALKALI BOROSILICATE GLASS

    Energy Technology Data Exchange (ETDEWEB)

    Marra, J.; Crawford, C.; Fox, K.; Bibler, N.

    2011-01-04

    The solubility of plutonium in a Sludge Batch 6 (SB6) reference glass and the effect of incorporation of Pu in the glass on specific glass properties were evaluated. A Pu loading of 1 wt % in glass was studied. Prior to actual plutonium glass testing, surrogate testing (using Hf as a surrogate for Pu) was conducted to evaluate the homogeneity of significant quantities of Hf (Pu) in the glass, determine the most appropriate methods to evaluate homogeneity for Pu glass testing, and to evaluate the impact of Hf loading in the glass on select glass properties. Surrogate testing was conducted using Hf to represent between 0 and 1 wt % Pu in glass on an equivalent molar basis. A Pu loading of 1 wt % in glass translated to {approx}18 kg Pu per Defense Waste Processing Facility (DWPF) canister, or about 10X the current allowed limit per the Waste Acceptance Product Specifications (2500 g/m{sup 3} of glass or about 1700 g/canister) and about 30X the current allowable concentration based on the fissile material concentration limit referenced in the Yucca Mountain Project License Application (897 g/m{sup 3}3 of glass or about 600 g Pu/canister). Based on historical process throughput data, this level was considered to represent a reasonable upper bound for Pu loading based on the ability to provide Pu containing feed to the DWPF. The task elements included evaluating the distribution of Pu in the glass (e.g. homogeneity), evaluating crystallization within the glass, evaluating select glass properties (with surrogates), and evaluating durability using the Product Consistency Test -- Method A (PCT-A). The behavior of Pu in the melter was evaluated using paper studies and corresponding analyses of DWPF melter pour samples.The results of the testing indicated that at 1 wt % Pu in the glass, the Pu was homogeneously distributed and did not result in any formation of plutonium-containing crystalline phases as long as the glass was prepared under 'well-mixed' conditions. The incorporation of 1 wt % Pu in the glass did not adversely impact glass viscosity (as assessed using Hf surrogate) or glass durability. Finally, evaluation of DWPF glass pour samples that had Pu concentrations below the 897 g/m{sup 3} limit showed that Pu concentrations in the glass pour stream were close to targeted compositions in the melter feed indicating that Pu neither volatilized from the melt nor stratified in the melter when processed in the DWPF melter.

  7. On fluidization of borosilicate glasses in intense radiation fields - 16055

    International Nuclear Information System (INIS)

    Ojovan, Michael; Moebus, Guenter; Tsai, Jim; Cook, Stuart; Yang, Guang

    2009-01-01

    The viscosity is rate-limiting for many processes in glassy materials such as homogenisation and crystallisation. Changes in the viscous flow behaviour in conditions of long-term irradiation are of particular interest for glassy materials used in nuclear installations as well as for nuclear waste immobilising glasses. We analyse the viscous flow behaviour of oxide amorphous materials in conditions of electron-irradiation using the congruent bond lattice model of oxide materials accounting for the flow-mediating role of broken bonds termed configurons. An explicit equation of viscosity was obtained which is in agreement with experimental data for non-irradiated glasses and shows for irradiated glasses, first, a significant decrease of viscosity, and, second, a stepwise reduction of the activation energy of flow. An equation for glass-transition temperature was derived which shows that irradiated glasses have lower glass transition temperatures. Intensive electron irradiation of glasses causes their fluidization due to non-thermal bond breaking and can occur below the glass transition temperature. Due to surface tension forces fluidization of glasses at enough high electron flux densities can result in modification of nano-size volumes and particles such as those experimentally observed under TEM electron beams. (authors)

  8. Ultrasonic and structural features of some borosilicate glasses ...

    Indian Academy of Sciences (India)

    ... was prepared and studied by Fourier transform infrared spectroscopy, density and ultrasonic techniques to debate the issue of the role of SiO2 in the structureof lead alkali borate glasses. The results indicate that SiO2 generates an abundance of bridging oxygen atoms, [BO 4 ] and [SiO 4 ] structural units and changes the ...

  9. Plutonium Solubility In High-Level Waste Alkali Borosilicate Glass

    International Nuclear Information System (INIS)

    Marra, J.; Crawford, C.; Fox, K.; Bibler, N.

    2011-01-01

    The solubility of plutonium in a Sludge Batch 6 (SB6) reference glass and the effect of incorporation of Pu in the glass on specific glass properties were evaluated. A Pu loading of 1 wt % in glass was studied. Prior to actual plutonium glass testing, surrogate testing (using Hf as a surrogate for Pu) was conducted to evaluate the homogeneity of significant quantities of Hf (Pu) in the glass, determine the most appropriate methods to evaluate homogeneity for Pu glass testing, and to evaluate the impact of Hf loading in the glass on select glass properties. Surrogate testing was conducted using Hf to represent between 0 and 1 wt % Pu in glass on an equivalent molar basis. A Pu loading of 1 wt % in glass translated to ∼18 kg Pu per Defense Waste Processing Facility (DWPF) canister, or about 10X the current allowed limit per the Waste Acceptance Product Specifications (2500 g/m 3 of glass or about 1700 g/canister) and about 30X the current allowable concentration based on the fissile material concentration limit referenced in the Yucca Mountain Project License Application (897 g/m 3 3 of glass or about 600 g Pu/canister). Based on historical process throughput data, this level was considered to represent a reasonable upper bound for Pu loading based on the ability to provide Pu containing feed to the DWPF. The task elements included evaluating the distribution of Pu in the glass (e.g. homogeneity), evaluating crystallization within the glass, evaluating select glass properties (with surrogates), and evaluating durability using the Product Consistency Test -- Method A (PCT-A). The behavior of Pu in the melter was evaluated using paper studies and corresponding analyses of DWPF melter pour samples.The results of the testing indicated that at 1 wt % Pu in the glass, the Pu was homogeneously distributed and did not result in any formation of plutonium-containing crystalline phases as long as the glass was prepared under 'well-mixed' conditions. The incorporation of 1 wt % Pu in the glass did not adversely impact glass viscosity (as assessed using Hf surrogate) or glass durability. Finally, evaluation of DWPF glass pour samples that had Pu concentrations below the 897 g/m 3 limit showed that Pu concentrations in the glass pour stream were close to targeted compositions in the melter feed indicating that Pu neither volatilized from the melt nor stratified in the melter when processed in the DWPF melter.

  10. Vanadium and Chromium Redox Behavior in borosilicate Nuclear Waste Glasses

    International Nuclear Information System (INIS)

    McKeown, D.; Muller, I.; Gan, H.; Feng, Z.; Viragh, C.; Pegg, I.

    2011-01-01

    X-ray absorption spectroscopy (XAS) was used to characterize vanadium (V) and chromium (Cr) environments in low activity nuclear waste (LAW) glasses synthesized under a variety of redox conditions. V 2 O 5 was added to the melt to improve sulfur incorporation from the waste; however, at sufficiently high concentrations, V increased melt foaming, which lowered melt processing rates. Foaming may be reduced by varying the redox conditions of the melt, while small amounts of Cr are added to reduce melter refractory corrosion. Three parent glasses were studied, where CO-CO 2 mixtures were bubbled through the corresponding melt for increasing time intervals so that a series of redox-adjusted-glasses was synthesized from each parent glass. XAS data indicated that V and Cr behaviors are significantly different in these glasses with respect to the cumulative gas bubbling times: V 4+ /V total ranges from 8 to 35%, while Cr 3+ /Cr total can range from 15 to 100% and even to population distributions including Cr 2+ . As Na-content decreased, V, and especially, Cr became more reduced, when comparing equivalent glasses within a series. The Na-poor glass series show possible redox coupling between V and Cr, where V 4+ populations increase after initial bubbling, but as bubbling time increases, V 4+ populations drop to near the level of the parent glass, while Cr becomes more reduced to the point of having increasing Cr 2+ populations.

  11. TiO3 borosilicate glass–ceramics

    Indian Academy of Sciences (India)

    on the stubs with Ag-conducting paint and photographs were recorded at a magnification of 1500, 5000, 8000 and 2500×. 2.6 Dielectric measurements. Both the surfaces of glass–ceramic samples were ground and polished using SiC powders (mesh nos 200, 400 and 1000) for attaining smooth surface for a thickness of ...

  12. Thermokinetic model of borosilicate glass dissolution: contextual affinity

    International Nuclear Information System (INIS)

    Advocat, T.; Vernaz, E.; Crovisier, J.L.; Fritz, B.

    1989-01-01

    Short and long-term geochemical interactions of R7T7 nuclear glass with water at 100 0 C were simulated with the DISSOL thermokinetic computer code. Both the dissolved glass quantity and the resulting water composition, saturation states and mineral quantities produced were calculated as a function of time. The rate equation used in the simulation was first proposed by Aagaard and Helgeson. It simulates a gradually diminishing dissolution rate as the reaction affinity diminishes. The best agreement with 1-year experimental data was obtained with a reaction affinity calculated from silica activity (Grambow's hypothesis) rather than taking into account the activity of all the glass components as proposed by Jantzen and Plodinec. The concept of residual affinity was introduced by Grambow to express the fact that the glass dissolution rate does not cease. We prefer to replace the term residual affinity by contextual affinity, which expresses the influence on the dissolution rate of three factors: the solution chemistry, the metastability of SiO 2 (m), and the possible precipitation of certain aluminosilicates such as zeolites. 19 refs

  13. Ultrasonic and structural features of some borosilicate glasses ...

    Indian Academy of Sciences (India)

    2017-06-09

    - perature in the quaternary glass system Na1.4B2.8Six Pb0.3−x O5.2+x on the parameter x (the lines are drawn as a guide to the eye). Another important parameter that depends on both the mean ultrasonic velocity and the ...

  14. Ultrasonic and structural features of some borosilicate glasses ...

    Indian Academy of Sciences (India)

    2017-06-09

    Jun 9, 2017 ... modified with heavy metals. YASSER B SADDEEK. Department of Physics, Faculty of .... acteristic broad humps of the amorphous materials. The FTIR absorption spectroscopy is a non-destructive .... and creates non-bridging oxygen (NBO) atoms on the [SiO4] silica tetrahedral [38]. Thus, the variation in the ...

  15. Electrical conductivity and viscosity of borosilicate glasses and melts

    DEFF Research Database (Denmark)

    Ehrt, Doris; Keding, Ralf

    2009-01-01

    , 0 to 62·5 mol% B2O3, and 25 to 85 mol% SiO2. The glass samples were characterised by different methods. Refractive indices, density and thermal expansion were measured. Phase separation effects were investigated by electron microscopy. The electrical conductivity of glasses and melts were determined...

  16. Porous vycor glass tube joined to borosilicate glass

    Science.gov (United States)

    Abe, Shinichi; Kikuchi, Takemitsu; Onodera, Shinji

    1992-09-01

    Porous glass can absorb various size of molecules with large surface area even in high temperature. However, it is difficult to use porous glass tubes at high-temperature, for example as a separation membrane for hydrogen condensation, because adhesives at joining sites could be damaged. In this study, welding of a porous glass tube and a glass tube was attempted to develop a gas separation membrane used at 500 C. Since forms present in porous glass may cause crack at high temperature, it is necessary to remove such forms by heat processing. Such porous glass is called to be porous vycor glass, which contains quartz 6 percents, and can be joined with a quartz tube. As a result, a gas separator with porous glass membrane which is joined by this process could endure high temperature up to 600 C and could maintain high vacuum.

  17. High-level nuclear waste borosilicate glass: A compendium of characteristics

    International Nuclear Information System (INIS)

    Cunnane, J.C.; Bates, J.K.; Ebert, W.L.; Feng, X.; Mazer, J.J.; Wronkiewicz, D.J.; Sproull, J.; Bourcier, W.L.; McGrail, B.P.

    1992-01-01

    With the imminent startup, in the United States, of facilities for vitrification of high-level nuclear waste, a document has been prepared that compiles the scientific basis for understanding the alteration of the waste glass products under the range of service conditions to which they may be exposed during storage, transportation, and eventual geologic disposal. A summary of selected parts of the content of this document is provided. Waste glass alterations in a geologic repository may include corrosion of the glass network due to groundwater and/or water vapor contact. Experimental testing results are described and interpreted in terms of the underlying chemical reactions and physical processes involved. The status of mechanistic modeling, which can be used for long-term predictions, is described and the remaining uncertainties associated with long-term simulations are summarized

  18. Partial Molar Liquidus Temperatures of Multivalent Elements in Multicomponent Borosilicate Glass

    Czech Academy of Sciences Publication Activity Database

    Hrma, P.; Izák, Pavel; Vienna, J. D.; Thomas, M. L.; Irwin, G. M.

    2002-01-01

    Roč. 43, č. 2 (2002), s. 119-127 ISSN 0031-9090 Grant - others:DOE(US) DE/AC06/76RLO1830 Keywords : molar liquids * multivalent elements * glass Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.691, year: 2002

  19. Influence of gel morphology on the corrosion kinetics of borosilicate glass: calcium and zirconium effect

    International Nuclear Information System (INIS)

    Cailleteau, C.

    2008-12-01

    This study is related to the question of the long-term behaviour of the nuclear waste confinement glass. A glass alteration layer (known as the 'gel'), formed at the glass surface in contact with water, can limit the exchanges between the glass and the solution. We studied five oxide based glasses SiO 2 -B 2 O 3 -Na 2 O-CaO-ZrO 2 . Two series of glasses were synthesized by substituting CaO for Na 2 O and ZrO 2 for SiO 2 . The leaching showed that the presence of Ca improves the reticulation of the vitreous network, inducing a decrease in the final degree of corrosion and the presence of Zr prevents the hydrolysis of silicon, which leads to a decrease of the initial dissolution rate. However, the introduction of Zr delays the drop of the alteration rate and leads to an increase in the alteration degree. In order to explain this unexpected behaviour, the gel morphology was investigated by small angle X-ray scattering. These experiments showed that the restructuring of porous network during the glass alteration process is limited by the increase of the Zr-content. Then, the restructuring of gel is at the origin of the major drop in the alteration rate observed for the low Zr-content glasses. Besides, both time-of-flight secondary-ion mass spectroscopy (ToF-SIMS) that provides an evaluation of extraneous element penetration into the gel pores and neutron scattering with index matching showed that the porosity closed during the corrosion in the glass without zirconia, but remained open in the high Zr-content glasses. These experiments, associated to simulations by a Monte Carlo method, establish a relationship between the morphologic transformations of gel and the alteration kinetics. (author)

  20. Physical and chemical characterization of borosilicate glasses containing Hanford high-level wastes

    International Nuclear Information System (INIS)

    Kupfer, M.J.; Palmer, R.A.

    1980-10-01

    Scouting studies are being performed to develop and evaluate silicate glass forms for immobilization of Hanford high-level wastes. Detailed knowledge of the physical and chemical properties of these glasses is required to assess their suitability for long-term storage or disposal. Some key properties to be considered in selecting a glass waste form include leach resistance, resistance to radiation, microstructure (includes devitrification behavior or crystallinity), homogeneity, viscosity, electrical resistivity, mechanical ruggedness, thermal expansion, thermal conductivity, density, softening point, annealing point, strain point, glass transformation temperature, and refractive index. Other properties that are important during processing of the glass include volatilization of glass and waste components, and corrosivity of the glass on melter components. Experimental procedures used to characterize silicate waste glass forms and typical properties of selected glass compositions containing simulated Hanford sludge and residual liquid wastes are presented. A discussion of the significance and use of each measured property is also presented

  1. X-ray tomography of feed-to-glass transition of simulated borosilicate waste glasses

    International Nuclear Information System (INIS)

    Harris, William H.; Guillen, Donna P.; Klouzek, Jaroslav; Pokorny, Richard; Yano, Tetsuji

    2017-01-01

    The feed composition of a high level nuclear waste (HLW) glass melter affects the overall melting rate by influencing the chemical, thermophysical, and morphological properties of a relatively insulating cold cap layer over the molten phase where the primary feed vitrification reactions occur. Data from X ray computed tomography imaging of melting pellets comprised of a simulated high-aluminum HLW feed heated at a rate of 10°C/min reveal the distribution and morphology of bubbles, collectively known as primary foam, within this layer for various SiO 2 /(Li 2 CO 3 +H 3 BO 3 +Na 2 CO 3 ) mass fractions at temperatures between 600°C and 1040°C. To track melting dynamics, cross-sections obtained through the central profile of the pellet were digitally segmented into primary foam and a condensed phase. Pellet dimensions were extracted using Photoshop CS6 tools while the DREAM.3D software package was used to calculate pellet profile area, average and maximum bubble areas, and two-dimensional void fraction. The measured linear increase in the pellet area expansion rates – and therefore the increase in batch gas evolution rates – with SiO 2 /(Li 2 CO 3 +H 3 BO 3 +Na 2 CO 3 ) mass fraction despite an exponential increase in viscosity of the final waste glass at 1050°C and a lower total amount of gas-evolving species suggest that the retention of primary foam with large average bubble size at higher temperatures results from faster reaction kinetics rather than increased viscosity. However, viscosity does affect the initial foam collapse temperature by supporting the growth of larger bubbles. Because the maximum bubble size is limited by the pellet dimensions, larger scale studies are needed to understand primary foam morphology at high temperatures. This temperature-dependent morphological data can be used in future investigations to synthetically generate cold cap structures for use in models of heat transfer within a HLW glass melter.

  2. Er 3–Al2O3 nanoparticles doping of borosilicate glass

    Indian Academy of Sciences (India)

    2O3 nanoparticles synthetized by using a soft chemical method. A similar nanoparticle doping with modified chemical vapour deposition (MCVD) process was developed to increase the efficiency of the amplifying silica fibre in comparison to ...

  3. Er –Al2O3 nanoparticles doping of borosilicate glass

    Indian Academy of Sciences (India)

    Administrator

    1Tampere University of Technology, Department of Electronics and Communications Engineering,. Korkeakoulunkatu 3, FI-33720 Tampere, Finland. 2Johan Gadolin Process Chemistry ..... The Finnish. Funding Agency for Technology and Innovation. (TEKES) is acknowledged by nLIGHT for financial support. References.

  4. Glass transition and crystallization kinetics of a barium borosilicate glass by a non-isothermal method

    International Nuclear Information System (INIS)

    Lopes, Andreia A. S.; Soares, Roque S.; Lima, Maria M. A.; Monteiro, Regina C. C.

    2014-01-01

    The glass transition and crystallization kinetics of a glass with a molar composition 60BaO-30B 2 O 3 -10SiO 2 were investigated by differential scanning calorimetry (DSC) under non-isothermal conditions. DSC curves exhibited an endothermic peak associated with the glass transition and two partially overlapped exothermic peaks associated with the crystallization of the glass. The dependence of the glass transition temperature (T g ) and of the maximum crystallization temperature (T p ) on the heating rate was used to determine the activation energy associated with the glass transition (E g ), the activation energy for crystallization (E c ), and the Avrami exponent (n). X-ray diffraction (XRD) revealed that barium borate (β-BaB 2 O 4 ) was the first crystalline phase to be formed followed by the formation of barium silicate (Ba 5 Si 8 O 21 ). The variations of activation energy for crystallization and of Avrami exponent with the fraction of crystallization (χ) were also examined. When the crystallization fraction (χ) increased from 0.1 to 0.9, the value of local activation energy (E c (χ)) decreased from 554 to 458 kJ/mol for the first exothermic peak and from 1104 to 831 kJ/mol for the second exothermic peak. The value determined for the Avrami exponent was near 2 indicating a similar one-dimensional crystallization mechanism for both crystalline phases. This was confirmed by the morphological studies performed by scanning electron microscopy (SEM) on glass samples heat-treated at the first and at the second crystallization temperatures

  5. Spectroscopic Properties of Erbium Ions Doped in Bismuth Boro-Silicate Glasses

    Science.gov (United States)

    Bhardwaj, Sunil; Shukla, Rajni; Sanghi, Sujata; Agarwal, Ashish; Pal, Inder

    Glasses with composition 20B2O3.(79.5-x)Bi2O3.xSiO2 (10 ≤ x ≤ 40) containing 0.5mol% of Er3+ ions were prepared by melt-quench technique. Optical absorption and fluorescence spectra were recorded at room temperature for all glass samples. Based on the Judd-Offelt theory, spectroscopic properties of Er3+ ions are discussed by changing the host glass compositions. The intensity parameters Ω2, Ω4, and Ω6 are determined by applying least square analysis method. The variation of Ω2 and Ω6 with Bi2O3 content has been attributed to changes in the asymmetry of the ligand field at the rare earth ion site and to the changes in the rare earth oxygen (RE-O) covalency. The variation of Ω4 with Bi2O3 content has been attributed to rigidity of the samples. Using these intensity parameters various radiative properties like spontaneous emission probability, branching ratio, radiative life time and stimulated emission cross-section of various emission lines have been evaluated. An intense green luminescence bands with maximum around 516 nm and 536 nm are assigned to the 2H11/2→ 4I15/2 and 4S3/2→ 4I15/2 transitions respectively has been obtained.

  6. Issues related to volatilization, phase alteration, and presence of unreacted feed in the borosilicate glass wasteform

    International Nuclear Information System (INIS)

    Jain, V.

    1994-01-01

    The U.S. Department of Energy's Office of Civilian Radioactive Waste Management has outlined the requirements in the Waste Acceptance Product Specifications (WAPS) that must be met before they will accept West Valley canistered vitrified waste forms for shipment to a federal depository. In this study the glass volatilization was studied using a thermogravimetric analyzer (TGA) to evaluate the absence of free gases, free liquids, explosives, pyrophorics, combustibles, and organics in the waste form. The total carbon in the samples was analyzed using a carbon determinator, phase alteration by heat-treating samples for extended periods of time (45-day) at T g -10 degrees C and T g +10 degrees C (where T g is the glass transition temperature), and the presence of unreacted feed in glass by comparing x-ray diffraction (XRD) patterns for glass and dried feed. The results of this study indicate that the West Valley vitrification process completely transforms the feed into glass. Also the TGA, XRD, and scanning transmission electron microscopy data indicates that there is no significant volatilization, redox reactions, and phase alterations in the waste form up to more than 200 degrees C above the T g . 7 refs., 1 fig., 4 tabs

  7. Disposal costs for SRP high-level wastes in borosilicate glass and crystalline ceramic waste forms

    International Nuclear Information System (INIS)

    Rozsa, R.B.; Campbell, J.H.

    1982-01-01

    Purpose of this document is to compare and contrast the overall burial costs of the glass and ceramic waste forms, including processing, storage, transportation, packaging, and emplacement in a repository. Amount of waste will require approximately 10,300 standard (24 in. i.d. x 9-5/6 ft length) canisters of waste glass, each containing about 3260 lb of waste at 28% waste loading. The ceramic waste form requires about one-third the above number of standard canisters. Approximately $2.5 billion is required to process and dispose of this waste, and the total cost is independent of waste form (glass or ceramic). The major cost items (about 80% of the total cost) for all cases are capital and operating expenses. The capital and 20-year operating costs for the processing facility are the same order of magnitude, and their sum ranges from about one-half of the total for the reference glass case to two-thirds of the total for the ceramic cases

  8. Er –Al2O3 nanoparticles doping of borosilicate glass

    Indian Academy of Sciences (India)

    Administrator

    sponding to the telecommunication window (the 4I13/2–. 4I15/2 transition).1 In the development of optical devices based on rare-earth (RE) ions, the local environment around the RE was found to be of paramount importance for determining the optical properties.2 While in homoge- neous glasses, RE elements tend to ...

  9. Effects of flow on corrosion and surface film formation on an alkali borosilicate glass

    International Nuclear Information System (INIS)

    Clark, D.E.; Christensen, H.; Hermansson, H.P.; Sundvall, S.B.; Werme, L.

    1984-01-01

    Samples of the Swedish KBS glass type ABS 39 have been leached in doubly distilled water for 28 days at 90 0 C under static and flow conditions. After leaching, pH, weight loss, and elemental mass loss were determined. Surface film formation was studied by using IRRS, SEM-EDS, and SIMS analyses. Increasing the flow rate resulted in a decreased attack on the glass surface. Na and B were depleted while Al, Fe, La, and U were enriched at the surfaces of all the samples. The depth of the extensively leached layer determined by SIMS was approximately 6 μm on the low-flow-rate sample and about 2 μm on the high-flow-rate sample. SEM analysis also showed some variations in the thickness of the leached layers, but in general, the thickness of the layer on the 0.5 mL/h samples was about 3 times greater than on the 90 mL/g samples. Small particles ( 2 for the static and 0.5 mL/h samples and 6 g/m 2 for the 90 mL/h samples. This factor of 3 difference in weight loss between the low and high flow rates correlates well with the factor of 3 difference in their leached depths. A model is proposed to explain the results based on the effectiveness of protective surface layers

  10. Simulation of Eu3+ luminescence spectra of borosilicate glasses by molecular dynamics calculations

    International Nuclear Information System (INIS)

    De Bonfils, J.; Panczer, G.; De Ligny, D.; Champagnon, B.; Peuget, S.; Delaye, J. M.; Chaussedent, S.; Monteil, A.

    2008-01-01

    Simplified inactive rare-earths doped nuclear waste glasses have been obtained by molecular dynamics (MD) simulation in order to investigate the local structure around the rare-earth by luminescence studies. MD calculations were performed with modified Born-Mayer-Huggins potentials and three body angular terms representing Coulomb and covalent interactions. Atomic positions within the glasses are then determined. Simulations of luminescence spectra were then obtained by calculation of the ligand field parameters affecting each luminescent ion. Considering the C 2v symmetry, it is possible to calculate the radiative transition probabilities between the emitter level, 5 D o , and the splitted receptor levels, 7 F J (J=0-3) for each Eu 3+ ion. The simulated emission spectra are obtained by convolution of all the Eu 3+ ions contributions. A comparison with the experimental data issue from fluorescence line narrowing and micro-luminescence spectroscopies allowed us not only to validate the simulation of luminescence spectra from simulated environments, but also to confirm the presence and the identification of two major Eu 3+ sites distribution in the nuclear glasses thanks to spectra-structure correlations. (authors)

  11. On the Morphology of the SDS Film on the Surface of Borosilicate Glass

    Directory of Open Access Journals (Sweden)

    Zih-Yao Shen

    2017-05-01

    Full Text Available Surfactant films on solid surfaces have attracted much attention because of their scientific interest and applications, such as surface treatment agent, or for micro- or nano-scale templates for microfluidic devices. In this study, anionic surfactant sodium dodecyl sulfate (SDS solutions with various charged inorganic salts was spread on a glass substrate and dried to form an SDS thin film. Atomic force microscopy (AFM was employed to observe the micro-structure of the SDS thin film. The effects of inorganic salts on the morphology of the SDS film were observed and discussed. The results of experiments demonstrated that pure SDS film formed patterns of long, parallel, highly-ordered stripes. The existence of the inorganic salt disturbed the structure of the SDS film due to the interaction between the cationic ion and the anionic head groups of SDS. The divalent ion has greater electrostatic interaction with anionic head groups than that of the monovalent ion, and causes a gross change in the morphology of the SDS film. The height of the SDS bilayer measured was consistent with the theoretical value, and the addition of the large-sized monovalent ion would lead to lowering the height of the adsorbed structures.

  12. Boro-Silicate Polycapillary Lens for Collimation of X-Rays

    National Research Council Canada - National Science Library

    Chase, Michael

    1997-01-01

    .... The electron beam was deflected 30 degrees using a rare earth permanent magnet. The diverging x-rays incident upon the lens array were transported through total external reflection and directed out of the array onto a phosphor screen...

  13. Phase formation during corrosion experiments with two simulated borosilicate nuclear waste glasses

    International Nuclear Information System (INIS)

    Haaker, R.F.

    1985-10-01

    Corrosion products resulting from the reaction of simulated high-level radioactive waste glasses with various solutions have been identified. At 200degC, in saturated NaCl, a degree of reaction of 10 g C31-3 glass or 2.6 g SON 68 glass per liter of solution was obtained. Analcime, vermiculite (a phyllosilicate) and a 2:1 zinc silicate are the major silica containing alteration products for the C31-3 glass. Analcime was the only silicate alteration product which could be identified for SON 68 glass. C31-3 glass appeared to be less reactive with a quinary brine containing Mg ++ than with NaCl. With the quinary brine, montmorillonite (a phyllosilicate) was the predominant silica containing alteration product. Hydrotalcite (a Mg-Al hydroxysulfate) and montmorillonite were the major Al-containing phases. A phyllosilicate, probably montmorillonite, was observed to form during the reaction of SON 68 glass with quinary brine. With either glass, modified NaCl brines which contained small amounts of MgCl 2 seem to have the effect of decreasing the amount of analcime and increasing the amount of phyllosilicate which is formed. In the case of C31-3 glass, there is approximately enough Mg, Al and Zn to precipitate most of the leached Si; measured Si concentrations remain well below that expected for amorphous silica. SON 68 glass has less Zn, Al and Mg than C31-3 glass and much higher Si concentrations of the leachates. (orig./RB)

  14. Impact of crystallization on the structure and chemical durability of borosilicate glass

    International Nuclear Information System (INIS)

    Nicoleau, Elodie

    2016-01-01

    This work describes a new approach to help understand the chemical durability of partially crystallized nuclear waste conditioning matrices. Among the studies carried out on nuclear waste deep geological disposal, long term behavior studies have so far been conducted on homogeneous glassy matrices. However, as the crystalline phases may generate modifications in the chemical composition and properties of such matrices, the description and a better understanding of their effects on the chemical durability of waste packages are of primary importance. A protocol to study the durability of heterogeneous model matrices of nuclear interest containing different types of crystalline phases was developed. It is based on a detailed description of the morphology, microstructure and structure of the glassy matrix and crystalline phases, and on the study of various alteration regimes. Three crystal phases that may form when higher concentrations of waste are immobilized in Uranium Oxide type conditioning glasses were studied: alkali and alkaline earth molybdates, rare earth silicates and ruthenium oxide. The results highlight the roles of the composition and the structure of the surrounding glassy matrix as the parameters piloting the alteration kinetics of the partially crystallized glassy matrices. This behavior is identical whatever the nature of the crystalline phases, as long as these phases do not lead to a composition gradient and do not percolate within the glassy matrix. Given these results, a methodology to study partially crystallized matrices with no composition gradient is then suggested. Its key development lies firstly in the evaluation of the behavior of partially crystallized matrices through the experimental study of the residual glassy matrix in various alteration regimes. This methodology may be adapted to the case of new glass formulations with more complex compositions (e.g. highly waste-loaded glass), which may contain crystals formed during cooling. (author) [fr

  15. Influence of gel morphology on the corrosion kinetics of borosilicate glass: calcium and zirconium effect; Influence de la morphologie du gel sur la cinetique d'alteration des verres borosilicates: role du calcium et du zirconium

    Energy Technology Data Exchange (ETDEWEB)

    Cailleteau, C

    2008-12-15

    This study is related to the question of the long-term behaviour of the nuclear waste confinement glass. A glass alteration layer (known as the 'gel'), formed at the glass surface in contact with water, can limit the exchanges between the glass and the solution. We studied five oxide based glasses SiO{sub 2}-B{sub 2}O{sub 3}-Na{sub 2}O-CaO-ZrO{sub 2}. Two series of glasses were synthesized by substituting CaO for Na{sub 2}O and ZrO{sub 2} for SiO{sub 2}. The leaching showed that the presence of Ca improves the reticulation of the vitreous network, inducing a decrease in the final degree of corrosion and the presence of Zr prevents the hydrolysis of silicon, which leads to a decrease of the initial dissolution rate. However, the introduction of Zr delays the drop of the alteration rate and leads to an increase in the alteration degree. In order to explain this unexpected behaviour, the gel morphology was investigated by small angle X-ray scattering. These experiments showed that the restructuring of porous network during the glass alteration process is limited by the increase of the Zr-content. Then, the restructuring of gel is at the origin of the major drop in the alteration rate observed for the low Zr-content glasses. Besides, both time-of-flight secondary-ion mass spectroscopy (ToF-SIMS) that provides an evaluation of extraneous element penetration into the gel pores and neutron scattering with index matching showed that the porosity closed during the corrosion in the glass without zirconia, but remained open in the high Zr-content glasses. These experiments, associated to simulations by a Monte Carlo method, establish a relationship between the morphologic transformations of gel and the alteration kinetics. (author)

  16. Volatility mechanisms of borosilicate glasses and molten glasses of nuclear interest structural effects; Mecanismes de volatilite des verres et des fontes borosilicates d'interet nucleaire influence de la structure

    Energy Technology Data Exchange (ETDEWEB)

    Delorme, L

    1998-04-23

    This work is devoted to the study of the mechanisms which control the volatility of the reference glass used for the confinement of radioactive waste. It was conducted on simplified compositions, in the SiO{sub 2}-B{sub 2}O{sub 3}-Al{sub 2}O{sub 3}-{alpha}Na{sub 2}O-(1-alpha)Li{sub 2}O-CaO system.The structural approach carried out by NMR, from room temperature up to 1500 deg.C, shows a strong increase in the mobility of alkalis above Tg. A rapid exchange between B{sup III} and B{sup IV} sites near 700 deg.C, and the change of coordination number B{sup IV-} B{sup III} near 1100 deg.C, also seem to take place. The analysis of the vapor phase, carried out by High Temperature Mass Spectrometry coupled to Knudsen cells, reveals the presence between 780 deg.C and 830 deg.C of NaBO{sub 2}(g), LiBO{sub 2}(g) and Na{sub 2}(BO{sub 2})2(g). The calculation of the partial pressure of each species shows that the total pressure of simplified glasses is dominated by the contribution of sodium. To study the volatility of glasses at higher temperature, equipment using the Transpiration method was used. The analysis of the deposits indicate the presence at 1060 deg.C of the species quoted previously. The vaporization rate and the vapor density were determined for each composition studied in a saturated state. Thus, we show that the volatility of the reference glass can be simulated by that of a simplified glass. For {alpha}=1, the kinetic of vaporization between 1060 deg.C and 1200 deg.C reveals an evaporation from the surface associated with a mechanism of diffusion in the molten glass. This is similar to the volatility of the reference glass at 1060 deg.C. To finally explain these mechanisms on a microscopic basis, we develop a model of molecular interactions. Between 780 deg.C and 830 deg.C, these mechanisms are controlled by a strong attraction between Na{sub 2}O and Li{sub 2}O, which maintains the total vapor pressure on a quasi-constant lever up to {alpha}=0.27. (author)

  17. Free volume of mixed cation borosilicate glass sealants elucidated by positron annihilation lifetime spectroscopy and its correlation with glass properties

    Science.gov (United States)

    Ojha, Prasanta K.; Rath, Sangram K.; Sharma, Sandeep K.; Sudarshan, Kathi; Pujari, Pradeep K.; Chongdar, Tapas K.; Gokhale, Nitin M.

    2015-01-01

    The role of La+3/Sr+2 ratios, which is varied from 0.08 to 5.09, on density, molar volume, packing fraction, free volume, thermal and electrical properties in strontium lanthanum aluminoborosilicate based glass sealants intended for solid oxide fuel cell (SOFC) applications is evaluated. The studies reveal expansion of the glass network evident from increasing molar volume and decreasing packing fraction of glasses with progressive La+3 substitutions. The molecular origin of these macroscopic structural features can be accounted for by the free volume parameters measured from positron annihilation lifetime spectroscopy (PALS). The La+3 induced expanded glass networks show increased number of subnanoscopic voids with larger sizes, as revealed from the ortho-positronium (o-Ps) lifetime and its intensity. A remarkably direct correspondence between the molar volume and fractional free volume trend is established with progressive La2O3 substitution in the glasses. The effect of these structural changes on the glass transition temperature, softening temperature, coefficient of thermal expansion, thermal stability as well as electrical conductivity has been studied.

  18. High temperature rheological study of borosilicate glasses containing platinum group metal particles by means of a mixer-type rheometer

    Energy Technology Data Exchange (ETDEWEB)

    Puig, Jean; Hanotin, Caroline [CEA Marcoule, DEN/MAR/DTCD/SECM/LDMC, Bagnols-sur-Cèze, F-30207 (France); Neyret, Muriel, E-mail: muriel.neyret@cea.fr [CEA Marcoule, DEN/MAR/DTCD/SECM/LDMC, Bagnols-sur-Cèze, F-30207 (France); Marchal, Philippe [Laboratoire Réactions et Génie des Procédés (LRGP-GEMICO), Université de Lorraine-CNRS, UMR 7274, Nancy, F-54001 (France)

    2016-02-15

    In this paper, the rheological behavior of six simulated high level waste nuclear glasses containing 0 to 5.2 wt% platinum group metals (PGM) has been studied at a temperature of 1200 °C. By means of a stress imposed rheometer, the shear stress dependence of the viscosity, which was so far assessed only at high shear rates, has been investigated on a wider range. Experimental data have been well fitted by the Cross model and a critical stress corresponding to the rupture of PGM aggregates has been evidenced. At high shear rates, the dependence with the volume fraction in PGM particles is well accounted for by Quemada's law. At low shear rates, the first Newtonian plateau is shown to be strongly dependent on the PGM content, notably above 3 wt% and to follow an exponential dependence due to the existence of more complex structures at the origin of the critical stress. - Highlights: • Rheological behavior of nuclear glass melts is well accounted by the Cross model. • A first Newtonian plateau has been evidenced at low shear. • First Newtonian plateau and critical stress values depend on PGM (Platinum Group Metals) content. • At high shear, Quemada's law well represents the PGM content impact on viscosity.

  19. FTIR and optical assessment of zinc doped calcium phospho-borosilicate sol-gel glasses/glass-ceramics

    Science.gov (United States)

    Kumar, V.; Arora, N.; Pandey, O. P.; Kaur, G.

    2015-08-01

    CaO-P2O5-ZnO-SiO2-B2O3 glasses with varying compositions of calcium oxide and phosphorous oxide are synthesized using sol-gel technique. The glasses are heat-treated for a duration of 10 h at 500°C to obtain the glass-ceramics. The glass-ceramics and glasses are characterized using Fourier transform infrared spectroscopy (FTIR) and UV-Visible spectroscopy. Extinction coefficients, attenuation coefficients and dielectric constant have been obtained for all the glasses as well as glass ceramics. The results are discussed in light of non-bridging oxygens (NBO) and heat-treatment of glasses. In addition to this, the effect of calcium and phosphorous on the infra-red spectra has been analysed thoroughly.

  20. Structural investigations of borosilicate glasses containing MoO{sub 3} by MAS NMR and Raman spectroscopies

    Energy Technology Data Exchange (ETDEWEB)

    Caurant, D., E-mail: daniel-caurant@enscp.f [Laboratoire de Chimie de la Matiere Condensee de Paris, UMR-CNRS 7574, Ecole Nationale Superieure de Chimie de Paris (ENSCP, ParisTech), 11 rue Pierre et Marie Curie, 75231 Paris (France); Majerus, O.; Fadel, E.; Quintas, A. [Laboratoire de Chimie de la Matiere Condensee de Paris, UMR-CNRS 7574, Ecole Nationale Superieure de Chimie de Paris (ENSCP, ParisTech), 11 rue Pierre et Marie Curie, 75231 Paris (France); Gervais, C. [Laboratoire de Chimie de la Matiere Condensee de Paris, UMR-CNRS 7574, Universite Pierre et Marie Curie, 75252 Paris (France); Charpentier, T. [CEA, IRAMIS, Service Interdisciplinaire sur les Systemes Moleculaires et Materiaux, CEA Saclay, 91191 Gif-sur-Yvette (France); Neuville, D. [Physique des Mineraux et des Magmas, UMR-CNRS 7047, Institut de Physique du Globe, place Jussieu, 75252 Paris (France)

    2010-01-01

    High molybdenum concentration in glass compositions may lead to alkali and alkaline-earth molybdates crystallization during melt cooling that must be controlled particularly during the preparation of highly radioactive nuclear glassy waste forms. To understand the effect of molybdenum addition on the structure of a simplified nuclear glass and to know how composition changes can affect molybdates crystallization tendency, the structure of two glass series belonging to the SiO{sub 2}-B{sub 2}O{sub 3}-Na{sub 2}O-CaO-MoO{sub 3} system was studied by {sup 29}Si, {sup 11}B, {sup 23}Na MAS NMR and Raman spectroscopies by increasing MoO{sub 3} or B{sub 2}O{sub 3} concentrations. Increasing MoO{sub 3} amount induced an increase of the silicate network reticulation but no significant effect was observed on the proportion of BO{sub 4}{sup -} units and on the distribution of Na{sup +} cations in glass structure. By increasing B{sub 2}O{sub 3} concentration, a strong evolution of the distribution of Na{sup +} cations was observed that could explain the evolution of the nature of molybdate crystals (CaMoO{sub 4} or Na{sub 2}MoO{sub 4}) formed during melt cooling.

  1. Phase Separation and Crystallization in soda-lime borosilicate glass enriched in MoO{sub 3} studied by in situ Raman spectroscopy at high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Magnin, M.; Schuller, S.; Advocat, T. [CEA Valrho, DEN/DTCD/SCDV, Laboratoire d' Etude de Base sur les Verres, BP 17171, 30207 Bagnols-sur-Ceze Cedex (France); Caurant, D.; Majerus, O. [Laboratoire de Chimie de la Matiere Condensee de Paris- LCMCP - UMR-CNRS 7574, Ecole Nationale Superieure de Chimie de Paris - ENSCP, Paristech, 75231 Paris (France); Ligny, D. de [Laboratoire de Physico-Chimie des Materiaux Luminescents- LPCML - UMR-CNRS 5620, Universite Claude Bernard Lyon1, 69622 Villeurbanne (France)

    2008-07-01

    Phase separation and crystallisation processes may arise in molten glass when the MoO{sub 3} content exceeds its solubility limit. Molybdenum combined with other elements such as alkali and alkaline-earth may form crystalline molybdates, known as 'yellow phases' in nuclear glasses. In order to establish the sequence of phase separation and crystallization processes occurring during the cooling of the melt, a non-radioactive simplified glass composition was chosen in the SiO{sub 2}-B{sub 2}O{sub 3}-Na{sub 2}O-CaO system, with 2 mol.% MoO{sub 3}. Various cooling scenarios were tested: cooling by air blowing, quenching between two copper plates and cooling on metallic plate. The resulting glass specimens were then characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Raman spectroscopy in temperature. These observations made it possible to determine the sequence and the appearance temperature of phenomena upon cooling: first, a phase separation occurs, (small droplets dispersed in the molten glass) followed by molybdates crystallization inside the droplets. (authors)

  2. Use of borosilicate-glass raschig rings as a neutron absorber in solutions of fissile material-ANSI/ANS-8.5-1996

    International Nuclear Information System (INIS)

    Rothe, R.E.; Ketzlach, N.; Finch, D.R.

    1996-01-01

    American National Standards Institute/American Nuclear Society (ANSI/ANS)-8.5 is one of several standards prepared by the ANS Standards Committee to provide guidance to enhance criticality safety in the handling, storage, and processing of fissionable materials. American National Standard ANSI/ANS-8.5-1996 provides this guidance for one type of boron-loaded glass in one type of geometry (cylindrical rings) for use with fissile solutions. Recorded use of such fixed neutron absorbers for criticality control of fissile solutions dates back to 1958, but some less-well-documented applications were recorded as early as the mid-1940's. The first solid efforts to collect recommendations derived from experience and technology were begun in 1965. Over the next 6 yr additional experiments were performed, and supporting data for the proposed standard were gathered. The first standard on this safety matter was issued in 1971. It was reaffirmed in 1979 with only minor changes and a slight expansion of the coverage. The standard was last revised in 1986

  3. Controlling Radiative Heat Transfer Across the Mold Flux Layer by the Scattering Effect of the Borosilicate Mold Flux System with Metallic Iron

    Science.gov (United States)

    Yoon, Dae-Woo; Cho, Jung-Wook; Kim, Seon-Hyo

    2017-08-01

    The present study proposes a countermeasure for regulating total heat flux through the mold flux layer by designed mold flux with additive metallic iron particles. The heat flux through the B2O3-CaO-SiO2-Na2O-CaF2-Fe system was investigated using the infrared emitter technique to evaluate total flux density across the mold flux film. Both scanning electron microscope (SEM) and X-ray diffraction analysis were employed in order to identify the morphological and compositional changes of the crystalline phase, according to increasing iron contents in the mold flux. It was confirmed that the crystalline layer of studied mold fluxes does not have a meaningful effect on the total heat flux density due to the similar structure and fraction of the crystalline phase. The extinction coefficient was measured for glassy mold fluxes using an ultraviolet/visible and a Fourier transformation-infrared ray spectrometer in the range of 0.5 to 5 μm. For analyzing the scattering behavior of iron particles on the extinction coefficient, the number density and diameter of particles were observed by an automated SEM (auto-SEM). With these data, Mie scattering theory is adopted to define the scattering behavior of dispersed iron droplets in glassy matrix. It was found that the theoretical scattering coefficient demonstrated about 1623 to 3295 m-1, which is in accordance with the experimental results. In doing so, this study successfully achieves the strong scattering behavior that would contribute greatly to the optimization of overall heat flux through the mold flux film during the casting process.

  4. A Facile and Green Method for the Synthesis of SFE Borosilicate Zeolite and Its Heteroatom-Substituted Analogues with Promising Catalytic Performances.

    Science.gov (United States)

    Luo, Yi; Wang, Zhendong; Sun, Junliang; Wang, Yingying; Jin, Shaoqing; Zhang, Bin; Sun, Hongmin; Yang, Weimin

    2018-01-09

    Synthesis of SFE-type borosilcate zeolite was successfully carried out using a commercially available low-cost organic structure directing agent (OSDA) with ultra-low OSDA and water contents within a short crystallization time. Heteroatom (Al, Ti, V, or Fe)-substituted SFE-type zeolite analogues were also directly synthesized for the first time. The obtained Al containing zeolites exhibited promising catalytic performances in the disproportionation of isopropylnaphthalene. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Recent progress to understand stress corrosion cracking in sodium borosilicate glasses: linking the chemical composition to structural, physical and fracture properties

    Science.gov (United States)

    Rountree, Cindy L.

    2017-08-01

    This topical review is dedicated to understanding stress corrosion cracking in oxide glasses and specifically the SiO_2{\\text-B_2O_3{\\text-}Na_2O} (SBN) ternary glass systems. Many review papers already exist on the topic of stress corrosion cracking in complex oxide glasses or overly simplified glasses (pure silica). These papers look at how systematically controlling environmental factors (pH, temperature...) alter stress corrosion cracking, while maintaining the same type of glass sample. Many questions still exist, including: What sets the environmental limit? What sets the velocity versus stress intensity factor in the slow stress corrosion regime (Region I)? Can researchers optimize these two effects to enhance a glass’ resistance to failure? To help answer these questions, this review takes a different approach. It looks at how systemically controlling the glass’ chemical composition alters the structure and physical properties. These changes are then compared and contrasted to the fracture toughness and the stress corrosion cracking properties. By taking this holistic approach, researchers can begin to understand the controlling factors in stress corrosion cracking and how to optimize glasses via the initial chemical composition.

  6. CsPbBr3:xEu3+ perovskite QD borosilicate glass: a new member of the luminescent material family.

    Science.gov (United States)

    Yuan, Rongrong; Shen, Lingli; Shen, Chenyang; Liu, Jianming; Zhou, Lei; Xiang, Weidong; Liang, Xiaojuan

    2018-03-29

    Eu3+ ions were introduced into the lattices of CsPbBr3 perovskite QDs and a tunable multicolour emission from CsPbBr3:xEu3+ perovskite QD glass was successfully obtained. Multicolour LEDs that were fabricated by combining the as-prepared CsPbBr3:xEu3+ QD glasses with a UV chip were also researched in this study.

  7. Thermal history-based etching

    Science.gov (United States)

    Simpson, John T.

    2017-11-28

    A method for adjusting an etchability of a first borosilicate glass by heating the first borosilicate glass; combining the first borosilicate glass with a second borosilicate glass to form a composite; and etching the composite with an etchant. A material having a protrusive phase and a recessive phase, where the protrusive phase protrudes from the recessive phase to form a plurality of nanoscale surface features, and where the protrusive phase and the recessive phase have the same composition.

  8. Spectral characterization and excited-state interactions between rare earth ions doped in borosilicate and sol-gel glasses. Energy transfer up-conversion in the Pr-Sm system

    International Nuclear Information System (INIS)

    Assefa, Z.; Haire, R.G.; Stump, N.A.

    1996-01-01

    Spectroscopic properties of selected 4f-elements in a sol-gel and two high temperature silicate based glasses are reported. In particular, the spectral properties of the Eu[sup 3+] ion have been used to probe the local coordination environment of the f-elements in these glass matrices. Luminescence studies of the high temperature glasses indicated that the electric dipole allowed f-f transitions dominate the spectra which suggests that the local symmetry around the 4f-ions is low. Temperature-dependent spectroscopic studies of the sol-gel glasses indicated that the f-elements retain a 'solution-like' environment prior to thermal processing. After heat treatment, an increase in the emission intensities of the electric-dipole transitions is accompanied by a concomitant decrease in the magnetic- dipole allowed transitions. Moreover, excited state interactions has also been observed in the high temperature glasses that contain certain multiple f-elements. In Pr-Sm systems, exclusive excitation of the Sm[sup 3+] ion with a 514 nm argon ion laser line provides a higher- energy emission band ( ca. 490 mn ) from the PR[sup 3+] ion ([sup 3]P[sub 0] -> '[sup 3]H[sub 4]) transition. This energy up- conversion is attributed to energy transfer from the [sup 6]H[sub 13/2] level of the Se[sup 3+] ion to the [sup 3]H[sub 6] state of the PR[sup 3+] ion. Following a second photon absorption, the PR[sup 3+] ion is excited to the emitting [sup 3]P[sub O] level

  9. Assessment of methods for immobilizing reprocessed radioactive waste

    Science.gov (United States)

    Murthy, M. K.; Baranyi, A. D.

    1980-05-01

    Nuclear waste forms presently used for the disposal of high level wastes and other potential waste forms under development were studied. The following waste forms were considered: Borosilicate glass, high silica glass, glassceramics, supercalcine ceramics, synroc ceramics, borosilicate glass beads in a metal matrix, supercalcine and synroc ceramics in a metal matrix and coated ceramics. The best developed wasteform, both in terms of overall product quality and process development, is monolithic borosilicate glass. However, hydrothermal instability is a major concern. Borosilicate glass in metal matrix waste form has better properties than monolithic borosilicate glass waste form. The process was proven on a pilot scale. Hence, it is considered very close to monolithic glass in terms of overall development. The product qualities of the other waste forms are better than borosilicate glass. However, process development for these alternative waste forms is still in a conceptual stage.

  10. Development of melt compositions for sulphate bearing high level waste

    International Nuclear Information System (INIS)

    Jahagirdar, P.B.; Wattal, P.K.

    1997-09-01

    The report deals with the development and characterization of vitreous matrices for sulphate bearing high level waste. Studies were conducted in sodium borosilicate and lead borosilicate systems with the introduction of CaO, BaO, MgO etc. Lead borosilicate system was found to be compatible with sulphate bearing high level wastes. Detailed product evaluation carried on selected formulations is also described. (author)

  11. Simulation, Measurements and Image Processing for Capillary Optical Digital Mammography

    National Research Council Canada - National Science Library

    Suprami, A

    2000-01-01

    .... A long prototype borosilicate magnifying tapered monolithic optic has demonstrated contrast enhancement due to removal of scatter transmission, while at the same time increasing the system MTF...

  12. Study of the possibilities of using nuclear methods for characterizing the surface region of glasses

    International Nuclear Information System (INIS)

    Hsiung, P.

    1983-01-01

    Following a review of the different methods used for the analysis of surfaces, we give a detailed description of charged particle elastic backscattering and the experimental devices. We then apply this method to the study of the lixiviation of borosilicate glasses in aqueous media and to the characterization of two heavy elements, cerium and thorium and their possible interaction in simple borosilicates [fr

  13. Thermophysical Properties of Matter - The TPRC Data Series. Volume 2. Thermal Conductivity - Nonmetallic Solids

    Science.gov (United States)

    1971-01-01

    3235 glass 2 92:1 Chamolle 2 «90 Borosilicate crown glass 2 >j2:t Chrome 2 4r)4, MJ7, Boxwood 2 1061 H’Jb Brass 1 5»i, r.92, Chrome fire brick...8217 Star-brand 2 185 Cadmiu n + Antimony 1 014 Tripolite 2 894 Cadmium - antimony i itermetallic compound Vermlcullte 2 894 CdSb 1 1 64 Zirconia 2 535...Borosilicate 3235 2 923 Solcx 2808 plate 2 923 Borosilicate crown 2 9;;) Solex 2808 X 2 925 Cellular 2 923 Solex "S" 2 925 Colorless 2 924

  14. Materials Characterization Center workshop on the leaching mechanisms of nuclear waste forms, December 7-8, 1982, Thousand Oaks, CA. Summary report

    International Nuclear Information System (INIS)

    Mendel, J.E.; Harker, A.B.

    1985-01-01

    Each of the six laboratories involved in the 3-yr leaching mechanism program presented a progress report on borosilicate glass studies. Presentations were made on various techniques for characterizing leached surfaces and on in situ characterization of leaching surfaces

  15. Preparation and Characterization of High-Temperature Hole Burning Materials

    National Research Council Canada - National Science Library

    Bommareddi, Rami

    2004-01-01

    .... Hole burning efficiency depends on the glass composition as well. We investigated persistent spectral hole burning studies in europium doped glasses such as sodium borates, silicates, borosilicates, germinates and tellurites...

  16. Study on the characteristics of vitrified waste form from OREOX process for dupic cycle

    International Nuclear Information System (INIS)

    Kim, J.H.; Chun, K.S.; Shin, J.M.; Kim, S.S.; Park, H.S.

    1996-01-01

    This paper describes the applicability of fly ash to the vitrification of the simulated OREOX process wastes in the aspects of productability, leachability, and preliminary characteristics of the simulated waste forms. Furthermore, vitrification of the spent filter into glass is an attractive option because it may be used as a base material for borosilicate glass. This paper also describes the possibility that the spent filter could be converted into a stable borosilicate glass form in this aspect. (author)

  17. An assessment of methods for immobilizing reprocessed radioactive waste

    International Nuclear Information System (INIS)

    Murthy, M.K.; Baranyi, A.D.

    1980-05-01

    Nuclear waste forms presently used for the disposal of high-level wastes and other potential waste forms under development were studied using information available in the literature and by visits to the laboratories. The following waste forms were considered: Borosilicate glass, high-silica glass, glassceramics, supercalcine ceramics, synroc ceramics, borosilicate glass beads in a metal matrix, supercalcine and synroc ceramics in a metal matrix and coated ceramics. The following conclusions have been reached: To date the best developed wasteform, both in terms of overall product quality and process development, is monolithic borosilicate glass. However, hydrothermal instability is a major concern. Borosilicate glass in metal matrix waste form has better properties than monolithic borosilicate glass waste form. The process has been proven on a pilot scale. Hence, it is considered very close to monolithic glass in terms of overall development. The product qualities of the other waste forms are better than borosilicate glass. However, process development for these alternative waste forms is still in a conceptual stage. The technological basis for processing ceramic waste forms exists in a well developed state. Nevertheless, adaptation of the technology to continuous hot-cell operation, although feasible, has not been demonstrated. In view of the product potential of ceramic waste forms it is felt that their development should be given emphasis at this time. (auth)

  18. A new glass option for parenteral packaging.

    Science.gov (United States)

    Schaut, Robert A; Peanasky, John S; DeMartino, Steven E; Schiefelbein, Susan L

    2014-01-01

    Glass is the ideal material for parenteral packaging because of its chemical durability, hermeticity, strength, cleanliness, and transparency. Alkali borosilicate glasses have been used successfully for a long time, but they do have some issues relating to breakage, delamination, and variation in hydrolytic performance. In this paper, alkali aluminosilicate glasses are introduced as a possible alternative to alkali borosilicate glasses. An example alkali aluminosilicate glass is shown to meet the compendial requirements, and to have similar thermal, optical, and mechanical attributes as the current alkali borosilicate glasses. In addition, the alkali aluminosilicate performed as well or better than the current alkali borosilicates in extractables tests and stability studies, which suggests that it would be suitable for use with the studied liquid product formulation. The physical, mechanical, and optical properties of glass make it an ideal material for packaging injectable drugs and biologics. Alkali borosilicate glasses have been used successfully for a long time for these applications, but there are some issues. In this paper, alkali aluminosilicate glasses are introduced as a possible alternative to alkali borosilicate glasses. An example alkali aluminosilicate glass is shown to meet the requirements for packaging injectable drugs and biologics, and to be suitable for use with a particular liquid drug. © PDA, Inc. 2014.

  19. Development of a glass matrix for vitrification of sulphate bearing high level radioactive liquid waste

    International Nuclear Information System (INIS)

    Kaushik, C.P.; Mishra, R.K.; Thorat, Vidya; Ramchandran, M.; Amar Kumar; Ozarde, P.D.; Raj, Kanwar; Das, D.

    2004-07-01

    High level radioactive liquid waste (HLW) is generated during reprocessing of spent nuclear fuel. In the earlier reprocessing flow sheet ferrous sulphamate has been used for valancy adjustment of Pu from IV to III for effective separation. This has resulted in generation of HLW containing significance amount of sulphate. Internationally borosilicate glass matrix has been adopted for vitrification of HLW. The first Indian vitrification facility at Waste Immobilislition Plant (WIP), Tarapur a five component borosilicate matrix (SiO 2 :B 2 O 3 :Na 2 O : MnO : TiO 2 ) has been used for vitrification of waste. However at Trombay HLW contain significant amount of sulphate which is not compatible with standard borosilicate formulation. Extensive R and D efforts were made to develop a glass formulation which can accommodate sulphate and other constituents of HLW e.g., U, Al, Ca, etc. This report deals with development work of a glass formulations for immobilization of sulphate bearing waste. Different glass formulations were studied to evaluate the compatibility with respect to sulphate and other constituents as mentioned above. This includes sodium, lead and barium borosilicate glass matrices. Problems encountered in different glass matrices for containment of sulphate have also been addressed. A glass formulation based on barium borosilicate was found to be effective and compatible for sulphate bearing high level waste. (author)

  20. Solubility of actinides and surrogates in nuclear glasses

    International Nuclear Information System (INIS)

    Lopez, Ch.

    2003-01-01

    The nuclear wastes are currently incorporated in borosilicate glass matrices. The resulting glass must be perfectly homogeneous. The work discussed here is a study of actinide (thorium and plutonium) solubility in borosilicate glass, undertaken to assess the extent of actinide solubility in the glass and to understand the mechanisms controlling actinide solubilization. Glass specimens containing; actinide surrogates were used to prepare and optimize the fabrication of radioactive glass samples. These preliminary studies revealed that actinide Surrogates solubility in the glass was enhanced by controlling the processing temperature, the dissolution kinetic of the surrogate precursors, the glass composition and the oxidizing versus reducing conditions. The actinide solubility was investigated in the borosilicate glass. The evolution of thorium solubility in borosilicate glass was determined for temperatures ranging from 1200 deg C to 1400 deg C.Borosilicate glass specimens containing plutonium were fabricated. The experimental result showed that the plutonium solubility limit ranged from 1 to 2.5 wt% PuO 2 at 1200 deg C. A structural approach based on the determination of the local structure around actinides and their surrogates by EXAFS spectroscopy was used to determine their structural role in the glass and the nature of their bonding with the vitreous network. This approach revealed a correlation between the length of these bonds and the solubility of the actinides and their surrogates. (author)

  1. Solubility of actinides and surrogates in nuclear glasses; Solubilite des actinides et de leurs simulants dans les verres nucleaires. Limites d'incorporation et comprehension des mecanismes

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, Ch

    2003-07-01

    The nuclear wastes are currently incorporated in borosilicate glass matrices. The resulting glass must be perfectly homogeneous. The work discussed here is a study of actinide (thorium and plutonium) solubility in borosilicate glass, undertaken to assess the extent of actinide solubility in the glass and to understand the mechanisms controlling actinide solubilization. Glass specimens containing; actinide surrogates were used to prepare and optimize the fabrication of radioactive glass samples. These preliminary studies revealed that actinide Surrogates solubility in the glass was enhanced by controlling the processing temperature, the dissolution kinetic of the surrogate precursors, the glass composition and the oxidizing versus reducing conditions. The actinide solubility was investigated in the borosilicate glass. The evolution of thorium solubility in borosilicate glass was determined for temperatures ranging from 1200 deg C to 1400 deg C.Borosilicate glass specimens containing plutonium were fabricated. The experimental result showed that the plutonium solubility limit ranged from 1 to 2.5 wt% PuO{sub 2} at 1200 deg C. A structural approach based on the determination of the local structure around actinides and their surrogates by EXAFS spectroscopy was used to determine their structural role in the glass and the nature of their bonding with the vitreous network. This approach revealed a correlation between the length of these bonds and the solubility of the actinides and their surrogates. (author)

  2. A statistically designed matrix to evaluate solubility, impurity tolerance, and thermal stability of plutonium-bearing glasses

    International Nuclear Information System (INIS)

    Peeler, D.K.; Meaker, T.F.; Edwards, T.B.; McIntyre, D.S.

    1997-01-01

    In support of the Department of Energy's (DOE) Office of Fissile Material Disposition (OFDM) Program, Westinghouse Savannah River Company (WSRC) is evaluating a unique lanthanide borosilicate glass to immobilize excess plutonium and other heavy metals. The lanthanide borosilicate (LaBS) glass system met all FY96 programmatic planning objectives. Those objectives were focused on (1) demonstrating 10 wt% Pu solubility, and (2) meeting preliminary product performance criteria. Although 10 wt% Pu solubility was demonstrated with product performance exceeding high level waste glasses based on PCT results, the LaBS system was not optimized

  3. Development and evaluation of candidate high-level waste forms

    International Nuclear Information System (INIS)

    Bernadzikowski, T.A.

    1981-01-01

    Some seventeen candidate waste forms have been investigated under US Department of Energy programs as potential media for the immobilization and geologic disposal of the high-level radioactive wastes (HLW) resulting from chemical processing of nuclear reactor fuels and targets. Two of these HLW forms were selected at the end of fiscal year (FY) 1981 for intensive development if FY 1982 to 1983. Borosilicate glass was continued as the reference form. A crystalline ceramic waste form, SYNROC, was selected for further product formulation and process development as the alternative to borosilicate glass. This paper describes the bases on which this decision was made

  4. Immobilization of Uranium Silicides in Sintered Glass

    International Nuclear Information System (INIS)

    Mateos, P.; Russo, D.O.; Heredia, A.D.; Sanfilippo, M.

    2003-01-01

    High activity nuclear spent fuels vitrification by fusion is a well known technology which has industrial scale in France, England, Japan, EEUU. Borosilicates glasses are used in this process.Sintered glasses are an alternative to the immobilization task in which there is also a wide experience around the world.The available technics are: cold pressing and sintering , hot-pressing and hot isostatic pressing.This work compares Borosilicates and Iron silicates sintered glasses behaviour when different ammounts of nuclear simulated waste is added

  5. Comparison of costs for solidification of high-level radioactive waste solutions: glass monoliths vs metal matrices

    Energy Technology Data Exchange (ETDEWEB)

    Jardine, L.J.; Carlton, R.E.; Steindler, M.J.

    1981-05-01

    A comparative economic analysis was made of four solidification processes for liquid high-level radioactive waste. Two processes produced borosilicate glass monoliths and two others produced metal matrix composites of lead and borosilicate glass beads and lead and supercalcine pellets. Within the uncertainties of the cost (1979 dollars) estimates, the cost of the four processes was about the same, with the major cost component being the cost of the primary building structure. Equipment costs and operating and maintenance costs formed only a small portion of the building structure costs for all processes.

  6. Assessment of processes, facilities, and costs for alternative solid forms for immobilization of SRP defense waste

    International Nuclear Information System (INIS)

    Dunson, J.B. Jr.; Eisenberg, A.M.; Schuyler, R.L. III; Haight, H.G. Jr.; Mello, V.E.; Gould, T.H. Jr.; Butler, J.L.; Pickett, J.B.

    1982-03-01

    A quantitative merit evaluation which assesses the relative difficulty of remote processing of Savannah River Plant high-level wastes for seven alternative waste forms is presented. The reference borosilicate glass process is rated as the simplest, followed by FUETAP concrete. The other processes evaluated in order of increasing complexity were: glass marbles in a lead matrix, high-silica glass, crystalline ceramic (Synroc-D and tailored ceramic), and coated ceramic particles. Cost appraisals are summarized for the borosilicate glass, high-silica glass, and ceramic waste form processing facilities

  7. Processability analysis of candidate waste forms

    International Nuclear Information System (INIS)

    Gould, T.H. Jr.; Dunson, J.B. Jr.; Eisenberg, A.M.; Haight, H.G. Jr.; Mello, V.E.; Schuyler, R.L. III.

    1982-01-01

    A quantitative merit evaluation, or processability analysis, was performed to assess the relative difficulty of remote processing of Savannah River Plant high-level wastes for seven alternative waste form candidates. The reference borosilicate glass process was rated as the simplest, followed by FUETAP concrete, glass marbles in a lead matrix, high-silica glass, crystalline ceramics (SYNROC-D and tailored ceramics), and coated ceramic particles. Cost estimates for the borosilicate glass, high-silica glass, and ceramic waste form processing facilities are also reported

  8. Method of processing combustible nuclear waste material

    International Nuclear Information System (INIS)

    Allen, C.R.; Greenhalgh, W.O.; Cowan, R.G.

    1982-01-01

    In treating combustible radio-waste which may contain volatile radio nuclides, e.g. Ru, the waste is heated and agitated with concentrated sulphuric acid, and the resulting residue which comprises elemental carbon which retains the volatile radio-nuclides is separated from the acid. Compounds which form borosilicate glass may be added to the waste, and after removal of sulphate, the resulting residual mixture may be fused into a glass. If the sulphate is not removed from the borosilicate mix, the residual mixture produces a ceramic product on heating. (author)

  9. Mercury reduction and removal during high-level radioactive waste processing and vitrification

    International Nuclear Information System (INIS)

    Eibling, R.E.; Fowler, J.R.

    1981-01-01

    A reference process for immobilizing the high-level radioactive waste in borosilicate glass has been developed at the Savannah River Plant. This waste contains a substantial amount of mercury from separations processing. Because mercury will not remain in borosilicate glass at the processing temperature, mercury must be removed before vitrification or must be handled in the off-gas system. A process has been developed to remove mercury by reduction with formic acid prior to vitrification. Additional benefits of formic acid treatment include improved sludge handling and glass melter redox control

  10. Gallium phosphide as a new material for anodically bonded atomic sensors

    Directory of Open Access Journals (Sweden)

    Nezih Dural

    2014-08-01

    Full Text Available Miniaturized atomic sensors are often fabricated using anodic bonding of silicon and borosilicate glass. Here we describe a technique for fabricating anodically bonded alkali-metal cells using GaP and Pyrex. GaP is a non-birefringent semiconductor that is transparent at alkali-metal resonance wavelengths, allowing new sensor geometries. GaP also has a higher thermal conductivity and lower He permeability than borosilicate glass and can be anodically bonded below 200 °C, which can also be advantageous in other vacuum sealing applications.

  11. Porous glass with high silica content for nuclear waste storage : preparation, characterization and leaching

    International Nuclear Information System (INIS)

    Aegerter, M.A.; Santos, D.I. dos; Ventura, P.C.S.

    1984-01-01

    Aqueous solutions simulating radioactive nuclear wastes (like Savanah River Laboratory) were incorporated in porous glass matrix with high silica content prepared by decomposition of borosilicate glass like Na 2 O - B 2 O 3 - SiO 2 . After sintering, the samples were submitted, during 28 days, to standard leaching tests MCC1, MCC5 (Soxhlet) and stagnating. The total weight loss, ph, as well as the integral and differential leaching rates and the accumulated concentrations in the leach of Si, Na, B, Ca, Mn, Al, Fe and Ni. The results are compared with the results from reference borosilicate glass, made by fusion, ceramic, synroc, concrets, etc... (E.G.) [pt

  12. Experiment to Characterize Sea Fighter FSF-1 Wave Slamming

    Science.gov (United States)

    2007-06-01

    Fighter Imaging Geometry. Figure 16. Camera deck arrangement. 15 " Borosilicate Window ŕ Camera Lonse (Cotw 20" Above Nick ) ~~3-Axis Camera HeadW...Alan Brandt . We would also like to acknowledge and thank Dr. L. Patrick Purtell and Ms. Jennifer McDonald, ONR for their continued support and

  13. Alternative solid forms for Savannah River Plant defense waste

    International Nuclear Information System (INIS)

    Stone, J.A.; Goforth, S.T.; Smith, P.K.

    1980-01-01

    Solid forms and processes were evaluated for immobilization of SRP high-level radioactive waste, which contains bulk chemicals such as hydrous iron and aluminium oxides. Borosilicate glass currently is the best overall choice. High-silica glass, tailored ceramics, and coated ceramics are potentially superior products, but require more difficult processes

  14. Bulletin of Materials Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Immobilization and solidification of hazardous cations like Cs137 and Sr90 are required while handling the radioactive waste of nuclear power plants. Efforts are on to find a fail proof method of safe disposal of nuclear wastes. In this context, various materials like borosilicate glass, zeolites, cements and synthetic rocks have ...

  15. Hydrothermal synthesis of LiFePO4 nanorods composed of ...

    Indian Academy of Sciences (India)

    Administrator

    bled in an argon-filled glove box (labstar, Mbraun, Ger- many). An electrochemical model cell was constructed using cathode, anode (Li metal), 1 M LiPF6 solution in ethylene carbonate–dimethyl carbonate (1 : 1 in volume) as the electrolyte (Chiel Industries Ltd., Korea) and a borosilicate glass fibre sheet as the separator.

  16. Aqueous corrosion of french R7T7 nuclear waste glass: selective then congruent dissolution by pH increase

    International Nuclear Information System (INIS)

    Advocat, T.; Vernaz, E.; Crovisier, J.L.

    1991-01-01

    A study of the corrosion of a borosilicate nuclear glass shows the strong effect of the pH on the dissolution mechanism. Acidic media lead to selective extraction of the glass modifier elements (Li, Na, Ca) as well as B, while dissolution is congruent under alkaline conditions. The silica dissolution rate significantly increases with increasing pH [fr

  17. Devendra Kumar

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. DEVENDRA KUMAR. Articles written in Bulletin of Materials Science. Volume 33 Issue 2 April 2010 pp 145-148 Ceramics and Glasses. IR study of Pb–Sr titanate borosilicate glasses · C R Gautam Devendra Kumar Om Parkash · More Details Abstract Fulltext PDF. The infrared ...

  18. Om Parkash

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. OM PARKASH. Articles written in Bulletin of Materials Science. Volume 33 Issue 2 April 2010 pp 145-148 Ceramics and Glasses. IR study of Pb–Sr titanate borosilicate glasses · C R Gautam Devendra Kumar Om Parkash · More Details Abstract Fulltext PDF. The infrared ...

  19. Oxide glass structure evolution under swift heavy ion irradiation

    International Nuclear Information System (INIS)

    Mendoza, C.; Peuget, S.; Charpentier, T.; Moskura, M.; Caraballo, R.; Bouty, O.; Mir, A.H.; Monnet, I.; Grygiel, C.; Jegou, C.

    2014-01-01

    Highlights: • Structure of SHI irradiated glass is similar to the one of a hyper quenched glass. • D2 Raman band associated to 3 members ring is only observed in irradiated glass. • Irradiated state seems slightly different to an equilibrated liquid quenched rapidly. - Abstract: The effects of ion tracks on the structure of oxide glasses were examined by irradiating a silica glass and two borosilicate glass specimens containing 3 and 6 oxides with krypton ions (74 MeV) and xenon ions (92 MeV). Structural changes in the glass were observed by Raman and nuclear magnetic resonance spectroscopy using a multinuclear approach ( 11 B, 23 Na, 27 Al and 29 Si). The structure of irradiated silica glass resembles a structure quenched at very high temperature. Both borosilicate glass specimens exhibited depolymerization of the borosilicate network, a lower boron coordination number, and a change in the role of a fraction of the sodium atoms after irradiation, suggesting that the final borosilicate glass structures were quenched from a high temperature state. In addition, a sharp increase in the concentration of three membered silica rings and the presence of large amounts of penta- and hexacoordinate aluminum in the irradiated 6-oxide glass suggest that the irradiated glass is different from a liquid quenched at equilibrium, but it is rather obtained from a nonequilibrium liquid that is partially relaxed by very rapid quenching within the ion tracks

  20. Boron nitride nanosheets reinforced glass matrix composites

    Czech Academy of Sciences Publication Activity Database

    Saggar, Richa; Porwal, H.; Tatarko, P.; Dlouhý, Ivo; Reece, M. J.

    2015-01-01

    Roč. 114, SEP (2015), S26-S32 ISSN 1743-6753 R&D Projects: GA MŠk(CZ) 7AMB14SK155 EU Projects: European Commission(XE) 264526 Institutional support: RVO:68081723 Keywords : Boron nitride nanosheets * Borosilicate glass * Mechanical properties Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 1.162, year: 2015

  1. B-TUD-1 : A versatile mesoporous catalyst

    NARCIS (Netherlands)

    Ranoux, A.; Djanashvili, K.; Arends, I.W.C.E.; Hanefeld, U.

    2013-01-01

    Novel amorphous mesoporous borosilicate, B-TUD-1, was prepared to test its performance for different sustainable reactions. The structure of the material, the effective incorporation of boron into the framework as well as the nature of incorporated boron were verified by N2-sorption, XRD, ICP-OES,

  2. Bulletin of Materials Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Precursor sol for sol–gel silica layer was prepared from the starting material, tetraethylorthosilicate (TEOS). The sol was deposited onto borosilicate ... The physical thicknessand the refractive index of the layer were measured ellipsometrically (Rudolph Auto EL II) at 632.8 nm. About 10 × 10 mm surface area of the silica ...

  3. Volume changes in glass induced by an electron beam

    Czech Academy of Sciences Publication Activity Database

    Gavenda, T.; Gedeon, O.; Jurek, Karel

    2014-01-01

    Roč. 322, Mar (2014), s. 7-12 ISSN 0168-583X Institutional support: RVO:68378271 Keywords : borosilicate glass * electron irradiation * densification * alkali migration Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 1.124, year: 2014

  4. Electroantennogram responses of the potato tuber moth ...

    Indian Academy of Sciences (India)

    PRAKASH

    and (v) sesquiterpenes (nerolidol, trans-caryophyllene and farnesol). All the compounds were of >90% purity except α-phellandrene and phenacetaldehyde. 2.3 Electroantennograms. EAGs were recorded from 2–3-day-old adults as described in Sen et al (2005). Glass capillary electrodes, drawn from borosilicate glass (1 ...

  5. Cation exchange applications of synthetic tobermorite for the ...

    Indian Academy of Sciences (India)

    Immobilization and solidification of hazardous cations like Cs137 and Sr90 are required while handling the radioactive waste of nuclear power plants. Efforts are on to find a fail proof method of safe disposal of nuclear wastes. In this context, various materials like borosilicate glass, zeolites, cements and synthetic rocks have ...

  6. Continuous-wave laser-induced glass fiber generation

    Science.gov (United States)

    Nishioka, Nobuyasu; Hidai, Hirofumi; Matsusaka, Souta; Chiba, Akira; Morita, Noboru

    2017-09-01

    Pulsed-laser-induced glass fiber generation has been reported. We demonstrate a novel glass fiber generation technique by continuous-wave laser illumination and reveal the generation mechanism. In this technique, borosilicate glass, metal foil, and a heat insulator are stacked and clamped by a jig as the sample. Glass fibers are ejected from the side surface of the borosilicate glass by laser illumination of the sample from the borosilicate glass side. SEM observation shows that nanoparticles are attached on the glass fibers. High-speed imaging reveals that small bubbles are formed at the side surface of the borosilicate glass and the bursting of the bubble ejects the fibers. The temperature at the fiber ejection point is estimated to be 1220 K. The mechanism of the fiber ejection includes the following steps: the metal thin foil heated by the laser increases the temperature of the surrounding glass by heat conduction. Since the absorption coefficient of the glass is increased by increasing the temperature, the glass starts to absorb the laser irradiation. The heated glass softens and bubbles form. When the bubble bursts, molten glass and gas inside the bubble scatter into the air to generate the glass fibers.

  7. Physical and chemical degradation behavior of sputtered aluminum doped zinc oxide layers for Cu(In,Ga)Se2 solar cells

    NARCIS (Netherlands)

    Theelen, M.; Boumans, T.; Stegeman, F.; Colberts, F.; Illiberi, A.; Berkum, J. van; Barreau, N.; Vroon, Z.; Zeman, M.

    2014-01-01

    Sputtered aluminum doped zinc oxide (ZnO:Al) layers on borosilicate glass were exposed to damp heat (85 C/85% relative humidity) for 2876 h to accelerate the physical and chemical degradation behavior. The ZnO:Al samples were characterized by electrical, compositional and optical measurements before

  8. Unusual photoluminescence of Cu–ZnO and its correlation with ...

    Indian Academy of Sciences (India)

    2017-11-15

    Nov 15, 2017 ... produced from surface adsorbed water, oxygen and hydroxyl groups. On the other hand, the photoexcited ... of the most priority pollutants present in waste and drinking water because of its acute carcinogenic and ... mercury vapour lamp of 125 W. The lamp was surrounded with a double-walled borosilicate ...

  9. Bulletin of Materials Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. OM PARKASH. Articles written in Bulletin of Materials Science. Volume 33 Issue 2 April 2010 pp 145-148 Ceramics and Glasses. IR study of Pb–Sr titanate borosilicate glasses · C R Gautam Devendra Kumar Om Parkash · More Details Abstract Fulltext PDF. The infrared ...

  10. Bulletin of Materials Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. DEVENDRA KUMAR. Articles written in Bulletin of Materials Science. Volume 33 Issue 2 April 2010 pp 145-148 Ceramics and Glasses. IR study of Pb–Sr titanate borosilicate glasses · C R Gautam Devendra Kumar Om Parkash · More Details Abstract Fulltext PDF. The infrared ...

  11. C R Gautam

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. C R Gautam. Articles written in Bulletin of Materials Science. Volume 33 Issue 2 April 2010 pp 145-148 Ceramics and Glasses. IR study of Pb–Sr titanate borosilicate glasses · C R Gautam Devendra Kumar Om Parkash · More Details Abstract Fulltext PDF. The infrared spectra ...

  12. Investigation of the state of polarization of light in a single-mode fiber waveguide

    Science.gov (United States)

    Kozel, S. M.; Kreopalov, V. I.; Listvin, V. N.; Glavatskikh, N. A.

    1983-01-01

    An analysis is made of the polarization anisotropy of a single-mode fiber with a twisted elliptic core. The Jones matrix is obtained and the complex function of the state of polarization of light in a fiber is investigated. The results are reported of measurements of the linear and circular birefringence of a borosilicate single-mode glass fiber.

  13. BRIEF COMMUNICATIONS: Investigation of the state of polarization of light in a single-mode fiber waveguide

    Science.gov (United States)

    Kozel, S. M.; Kreopalov, V. I.; Listvin, V. N.; Glavatskikh, N. A.

    1983-01-01

    An analysis is made of the polarization anisotropy of a single-mode fiber with a twisted elliptic core. The Jones matrix is obtained and the complex function of the state of polarization of light in a fiber is investigated. The results are reported of measurements of the linear and circular birefringence of a borosilicate single-mode glass fiber.

  14. Direct conversion of plutonium metal, scrap, residue, and transuranic waste to glass

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.; Malling, J.F.; Rudolph, J.

    1995-01-01

    A method for the direct conversion of metals, ceramics, organics, and amorphous solids to borosilicate glass has been invented. The process is called the Glass Material Oxidation and Dissolution System (GMODS). Traditional glass-making processes can convert only oxide materials to glass. However, many wastes contain complex mixtures of metals, ceramics, organics, and amorphous solids. Conversion of such mixtures to oxides followed by their conversion to glass is often impractical. GMODS may create a practical method to convert such mixtures to glass. Plutonium-containing materials (PCMS) exist in many forms, including metals, ceramics, organics, amorphous solids, and mixtures thereof. These PCMs vary from plutonium metal to filters made of metal, organic binders, and glass fibers. For storage and/or disposal of PCMS, it is desirable to convert PCMs to borosilicate glass. Borosilicate glass is the preferred repository waste form for high-level waste (HLW) because of its properties. PCMs converted to a transuranic borosilicate homogeneous glass would easily pass all waste acceptance and storage criteria. Conversion of PCMs to a glass would also simplify safeguards by conversion of heterogeneous PCMs to homogeneous glass. Thermodynamic calculations and proof-of-principle experiments on the GMODS process with cerium (plutonium surrogate), uranium, stainless steel, aluminum, Zircaloy-2, and carbon were successfully conducted. Initial analysis has identified potential flowsheets and equipment. Major unknowns remain, but the preliminary data suggests that GMODS may be a major new treatment option for PCMs

  15. Behaviour of rare earth elements, as natural analogues of transuranium elements, during weathering of basaltic glasses

    International Nuclear Information System (INIS)

    Daux, V.; Crovisier, J.L.; Petit, J.C.

    1991-01-01

    Subglacial basaltic glasses from Iceland have been studied in order to investigate REE behaviour low-temperature weathering. Just as actinides accumulate in the hydrated superficial corrosion layer of borosilicate glasses, REEs are found to be enriched in the natural corrosion layer of basaltic glasses (palagonite). However, this enrichment is only relative for basaltic glasses [fr

  16. Radiation transport in high-level waste form

    International Nuclear Information System (INIS)

    Arakali, V.S.; Barnes, S.M.

    1992-01-01

    The waste form selected for vitrifying high-level nuclear waste stored in underground tanks at West Valley, NY is borosilicate glass. The maximum radiation level at the surface of a canister filled with the high-level waste form is prescribed by repository design criteria for handling and disposition of the vitrified waste. This paper presents an evaluation of the radiation transport characteristics for the vitreous waste form expected to be produced at West Valley and the resulting neutron and gamma dose rates. The maximum gamma and neutron dose rates are estimated to be less than 7500 R/h and 10 mRem/h respectively at the surface of a West Valley canister filled with borosilicate waste glass

  17. Influence of iron ions on the structural properties of some inorganic glasses

    International Nuclear Information System (INIS)

    Music, S.; Gotic, M.; Popovic, S.; Grzeta, B.

    1987-01-01

    The effects of iron on the structural properties of Zn-borosilicate glass and Pb-metaphosphate glass were studied using x-ray diffraction, 57 Fe Moessbauer spectroscopy and IR spectroscopy. At high concentration of iron the crystallization of zinc ferrite in the glass matrix takes place. X-ray diffraction and 57 Fe Moessbauer spectroscopy showed that the amount of zinc ferrite in Zn-borosilicate glass decreases. In Pb-metaphosphate glass doped with high concentration of α-Fe 2 O 3 , the crystallization of Fe 3 (PO 4 ) 2 is pronounced. The assignments of IR band positions and the corresponding interpretation are given. The importance of this study for the technology of vitrification of high-level radioactive wastes is emphasized. (author) 31 refs.; 6 figs,.; 6 tabs

  18. Development of confocal X-ray fluorescence (XRF) microscopy at the Cornell high energy synchrotron source

    International Nuclear Information System (INIS)

    Woll, A.R.; Huang, R.; Mass, J.; Bisulca, C.; Bilderback, D.H.; Gruner, S.; Gao, N.

    2006-01-01

    A confocal X-ray fluorescence microscope was built at the Cornell High Energy Synchrotron Source (CHESS) to obtain compositional depth profiles of historic paintings. The microscope consists of a single-bounce, borosilicate monocapillary optic to focus the incident beam onto the painting and a commercial borosilicate polycapillary lens to collect the fluorescent X-rays. The resolution of the microscope was measured by scanning a variety of thin metal films through this confocal volume while monitoring the fluorescence signal. The capabilities of the technique were then probed using test paint microstructures with up to four distinct layers, each having a thickness in the range of 10-80 microns. Results from confocal XRF were compared with those from stand-alone XRF and visible light microscopy of the paint cross-sections. A large area, high-resolution scanner is currently being built to perform 3D scans on moderately sized paintings. (orig.)

  19. Preliminary evaluation of alternative forms for immobilization of Hanford high-level wastes

    International Nuclear Information System (INIS)

    Schulz, W.W.; Beary, M.M.; Gallagher, S.A.; Higley, B.A.; Johnston, R.G.; Kupfer, M.J.; Palmer, R.A.

    1981-01-01

    Borosilicate Glass Marbles and/or monoliths were rated among the top three waste forms for immobilization of all types of Hanford high-level waste. Supergrout Concrete and Bitumen, low temperature processes, are judged to be particularly suitable for immobilization and bulk disposal of high sodium blended wastes and/or residual liquid. This preliminary assessment indicates that certain ceramic waste forms (e.g., Tailored Ceramics, Supercalcine Ceramic, and SYNROC Ceramic) are equal to or superior to Borosilicate Glass waste forms for immobilization of Hanford sludges and radionuclides removed from salt cake and residual liquid. These ceramic waste forms can be made by the Sol Gel process. Some multibarrier waste forms (e.g., Coated Ceramics, Ceramic Pellets in Metal Matrix, and Glass in Metal Matrix) are judged to be superior waste forms for immobilization of Hanford sludges and/or radionuclide concentrate

  20. The effect of surface roughness of glass on the leachability

    International Nuclear Information System (INIS)

    Yamanaka, Hiroshi; Terai, Ryohei; Hara, Shigeo

    1982-01-01

    The effect of surface roughness of glass samples on the leachability of simulated high-level nuclear waste containing borosilicate glasses has been investigated from view-point of safety evaluation, using the Soxhlet-type leaching apparatus. The quantity extracted from glasses had generally increased with increasing of the surface roughness of glass block samples. SEM photographs demonstrated that the surface abraded by coarse abrasive powder has had many unevennesses and cracks which brought about an accelerated attack on glass surface. It seems, therefore, that the surface roughness of specimens should be defined as a criterion of leachability. The reaction between glass and water brought about the formation of hydrated layer more easily on the borosilicate glass than on the soda-lime silicate glass. The resultant hydrated layer produces many cracks by drying, but the cracks can not be observed by naked eye. Therefore, the observation by SEM is necessary for precise evaluation on the corroded surface of glasses. (author)

  1. Conversion of ion-exchange resins, catalysts and sludges to glass with optional noble metal recovery using the GMODS process

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Beahm, E.C.

    1996-01-01

    Chemical processing and cleanup of waste streams (air and water) typically result in products, clean air, clean water, and concentrated hazardous residues (ion exchange resins, catalysts, sludges, etc.). Typically, these streams contain significant quantities of complex organics. For disposal, it is desirable to destroy the organics and immobilize any heavy metals or radioactive components into stable waste forms. If there are noble metals in the residues, it is desirable to recover these for reuse. The Glass Material Oxidation and Dissolution System (GMODS) is a new process that directly converts radioactive and hazardous chemical wastes to borosilicate glass. GMODS oxidizes organics with the residue converted to glass; converts metals, ceramics, and amorphous solids to glass; converts halides (eg chlorides) to borosilicate glass and a secondary sodium halide stream; and recovers noble metals. GMODS has been demonstrated on a small laboratory scale (hundreds of grams), and the equipment needed for larger masses has been identified

  2. Waste glass corrosion modeling: Comparison with experimental results

    International Nuclear Information System (INIS)

    Bourcier, W.L.

    1994-01-01

    Models for borosilicate glass dissolution must account for the processes of (1) kinetically-controlled network dissolution, (2) precipitation of secondary phases, (3) ion exchange, (4) rate-limiting diffusive transport of silica through a hydrous surface reaction layer, and (5) specific glass surface interactions with dissolved cations and anions. Current long-term corrosion models for borosilicate glass employ a rate equation consistent with transition state theory embodied in a geochemical reaction-path modeling program that calculates aqueous phase speciation and mineral precipitation/dissolution. These models are currently under development. Future experimental and modeling work to better quantify the rate-controlling processes and validate these models are necessary before the models can be used in repository performance assessment calculations

  3. Optical waveguides in magneto-optical glasses fabricated by proton implantation

    Science.gov (United States)

    Liu, Chun-Xiao; Li, Yu-Wen; Zheng, Rui-Lin; Fu, Li-Li; Zhang, Liao-Lin; Guo, Hai-Tao; Zhou, Zhi-Guang; Li, Wei-Nan; Lin, She-Bao; Wei, Wei

    2016-11-01

    Planar waveguides in magneto-optical glasses (Tb3+-doped aluminum borosilicate glasses) have been produced by a 550-keV proton implantation at a dose of 4.0×1016 ions/cm2 for the first time to our knowledge. After annealing at 260 °C for 1.0 h, the dark-mode spectra and near-field intensity distributions are measured by the prism-coupling and end-face coupling methods. The damage profile, refractive index distribution and light propagation mode of the planar waveguide are numerically calculated by SRIM 2010, RCM and FD-BPM, respectively. The effects of implantation on the structural and optical properties are investigated by Raman and absorption spectra. It suggests that the proton-implanted Tb3+-doped aluminum borosilicate glass waveguide is a good candidate for a waveguide isolator in optical fiber communication and all-optical communication.

  4. Silicate glasses

    International Nuclear Information System (INIS)

    Lutze, W.

    1988-01-01

    Vitrification of liquid high-level radioactive wastes has received the greatest attention, world-wide, compared to any other HLW solidification process. The waste form is a borosilicate-based glass. The production of phosphate-based glass has been abandoned in the western world. Only in the Soviet Union are phosphate-based glasses still being developed. Vitrification techniques, equipment and processes and their remote operation have been developed and studied for almost thirty years and have reached a high degree of technical maturity. Industrial demonstration of the vitrification process has been in progress since 1978. This chapter is a survey of world-wide research and development efforts in nuclear waste glasses and its production technology. The principal glasses considered are silicate glasses which contain boron, i.e., borosilicate glasses

  5. IMPROVED BAR IMPACT TESTS USING A PHOTONIC DOPPLER VELOCIMETER

    Energy Technology Data Exchange (ETDEWEB)

    Bless, S J; Tolman, J; Levinson, S; Nguyen, J

    2009-08-24

    Bar impact tests, using the techniques described elsewhere in this symposium, were used to measure compressive and tensile strengths of borosilicate glass, soda lime glass, and a glass ceramic. The glass ceramic was 25% crystalline spinel, furnished by Corning Inc. There are two measures of compressive strength: the peak stress that can be transmitted in unconfined compression, and the 'steady state' strength. For borosilicate glass and soda lime glass, these values were similar, being about 1.8 and 1.5 GPa, respectively. The glass ceramic (25% spinel) was almost 50% stronger. Tensile failure in the glass and glass ceramic takes places via surface flaws, and thus tensile strength is an extrinsic, as opposed to intrinsic property.

  6. Corrosion of simulated nuclear waste glass

    International Nuclear Information System (INIS)

    Music, S.; Ristic, M.; Gotic, M.; Foric, J.

    1988-01-01

    In this study the preparation and characterization of borosilicate glasses of different chemical composition were investigated. Borosilicate glasses were doped with simulated nuclear waste oxides. The chemical corrosion in water of these glasses was followed by measuring the leach rates as a function of time. It was found that a simulated nuclear waste glass with the chemical composition (weight %), 15.61% Na 2 O, 10.39% B 2 O 3 , 45.31% SiO 2 , 13.42% ZnO, 6.61% TiO 2 and 8.66% waste oxides, is characterized by low melting temperature and with good corrosion resistance in water. Influence of passive layers on the leaching behaviour of nuclear waste glasses is discussed. (author) 20 refs.; 7 figs.; 4 tabs

  7. IR spectroscopic investigation of the structure of glasses containing a sol of burned radioactive by-products

    International Nuclear Information System (INIS)

    Stefanovskii, S.V.; Ivanov, I.A.; Gulin, A.N.

    1993-01-01

    On glassification of sols from the burning apparatus of radioactive by-products (RAB) using sodium borate, sodium silicate, or borosilicate flux, glassy materials suitable for long-time storage or final burying are obtained. Technological and ecologically important properties of glassified RAB are determined by their structure. In some preliminary results are presented of a study of the structure of silicate and borosilicate glasses containing a sol of concrete composition. In a real sol from technological apparatus the qualitative and quantitative relations of the ingredients vary within broad limits. The purpose of this work is a systematic investigation of the structure of sol-containing glassy materials depending on their composition using IR spectroscopy. 16 refs., 4 figs., 3 tabs

  8. Sulphate solubility and sulphate diffusion in oxide glasses: implications for the containment of sulphate-bearing nuclear wastes

    International Nuclear Information System (INIS)

    Lenoir, M.

    2009-09-01

    The thesis deals with sulphate solubility and sulphate diffusion in oxide glasses, in order to control sulphate incorporation and sulphate volatilization in nuclear waste glasses. It was conducted on simplified compositions, in the SiO 2 -B 2 O 3 -R 2 O (R = Li, Na, K, Cs), SiO 2 -B 2 O 3 -BaO and V 2 O 5 -B 2 O 3 -BaO systems. These compositions allowed us to study the influence of the nature of network-modifying ions (Li + , Na + , K + , Cs + or Ba 2+ ) and also of former elements (Si, B, V), on structure and properties of glasses. Sulphate volatility is studied in sodium borosilicate melts using an innovative technique of sulphate quantitation with Raman spectroscopy. This technique is useful to obtain kinetic curves of sulphate volatilization. The establishment of a model to fit these curves leads to the determination of diffusion coefficients of sulphate. These diffusion coefficients can thus be compared to diffusion coefficients of other species, determined by other techniques and presented in the literature. They are also linked to diffusion coefficients in relation with the viscosity of the melts. Concerning sulphate solubility in glasses, it depends on glass composition and on the nature of sulphate incorporated. Sulphate incorporation in alkali borosilicate glasses leads to the formation of a sulphate layer floating on top of the melt. Sulphate incorporation in barium borosilicate and boro-vanadate glasses leads to the crystallization of sulphate species inside the vitreous matrix. Moreover, sulphate solubility is higher in these glasses than in alkali borosilicates. Finally, exchanges between cations present in glasses and cations present in the sulphate phase are also studied. (author)

  9. Způsoby vitrifikace vysoceaktivních odpadů, vznikajících při přepracování vyhořelého jaderného paliva

    OpenAIRE

    Machová, Pavlína

    2011-01-01

    This thesis summarizes the general concepts regarding the High-level waste vitrification. It describes the one-stage and two-stage principles of vitrification and special method "cold crucible". There are summarized advantages and disadvantages of these methods. In this thesis are specific of vitrification facilities around the world. There are the general characteristics of glass used for immobilization High- level waste. Most countries use borosilicate glass, but only in Russia are used pho...

  10. Immobilization of radioactive waste in glass matrices

    International Nuclear Information System (INIS)

    Wicks, G.G.

    1978-01-01

    A promising process for long-term management of high-level radioactive waste is to immobilize the waste in a borosilicate glass matrix. Among the most important criteria characterizing the integrity of the large-scale glass-waste forms are that they possess good chemical stability (including low leachability), thermal stability, mechanical integrity, and high radiation stability. Fulfillment of these criteria ensures the maximum margin of safety of glass-waste products, following solidification, handling, transportation, and long-term storage

  11. Thermal conductivity of solidified waste products

    International Nuclear Information System (INIS)

    Neumann, W.

    1979-11-01

    Thermal conductivity is an important property of solidified high-level waste with regard to the dissipation of radiation induced heat. Measurements of the conductivity of waste calcines from spray and fluidized bed calciner, HLW borosilicate glass and waste containing ceramic granules embedded in metal matrix are described. The results obtained are compared with many data published, a short review over conductivity values of alternative waste products is given. (author)

  12. Characterization and photocatalytic treatability of red water from Brazilian TNT industry

    Energy Technology Data Exchange (ETDEWEB)

    Ludwichk, Raquel [Department of Chemistry, Postgraduate Programme in Technology of Chemical and Biochemical Processes, Federal Technological University of Paraná, Pato Branco, PR (Brazil); Helferich, Oliver Karil; Kist, Cristiane Patrícia [Academic Department of Chemistry and Biology, Post graduation in Environmental Science and Technology Federal Technological University of Paraná, Curitiba, PR (Brazil); Lopes, Aline Chitto; Cavasotto, Thiago [Department of Chemistry, Postgraduate Programme in Technology of Chemical and Biochemical Processes, Federal Technological University of Paraná, Pato Branco, PR (Brazil); Silva, Davi Costa [Academic Department of Chemistry and Biology, Post graduation in Environmental Science and Technology Federal Technological University of Paraná, Curitiba, PR (Brazil); Barreto-Rodrigues, Marcio, E-mail: marciorodrigues@utfpr.edu.br [Department of Chemistry, Postgraduate Programme in Technology of Chemical and Biochemical Processes, Federal Technological University of Paraná, Pato Branco, PR (Brazil); Academic Department of Chemistry and Biology, Post graduation in Environmental Science and Technology Federal Technological University of Paraná, Curitiba, PR (Brazil)

    2015-08-15

    Highlights: • The red water effluent has high levels of COD, color and acute toxicity. • The compounds 2-methyl-1, 3-dinitrobenzene, 1-methyl-2, 4-dinitrobenzene and 1-methyl-3, 5-dinitrobenzene were identified. • A nanostructured TiO{sub 2}-borosilicate glass was obtained and characterized. • The photocatalytic treatment removes all color 32% of the organic matter content of the effluent. • The borosilicate-glass-TiO{sub 2} system degrades all content of identified nitroaromatic compounds. - Abstract: The current study aims to characterize and evaluate the photocatalytic treatability of the “red water” effluent from a Brazilian TNT production industry. Analyses were performed using physical, chemical, spectroscopic and chromatographic assays, which demonstrated that the effluent presented a significant pollution potential, mainly due to COD, BOD, solids and to the high concentration of nitroaromatic compounds such as 1,3,5-trinitrobenzene, 1-methyl-2,4-dinitrobenzene, 2-methyl-1,3-dinitrobenzene, 2,4,6-trinitrotoluene-3,5-dinitro-p-toluidine and 2-methyl-3,5-dinitro-benzoamine. By a modified sol-gel and a dip-coating technique, it was possible to obtain a TiO{sub 2} film on borosilicate glass substrate which functional composition and microstructure were characterized by infrared spectroscopy and scanning electron microscopy. The evaluation of the photocatalytic treatability using borosilicate-glass-TiO{sub 2} demonstrated high degradation efficiency. In this context, a reduction of 32 and 100% for COD and nitroaromatic compounds, respectively, was observed. Although the proposed photocatalytic process has found difficulties in reducing the content of organic matter and effluent color in the red water, its potential for degrading refractory chemical compounds such as the nitroaromatic ones enables it to be used as tertiary treatment.

  13. Development of Non-Toxic Quantum Dots for Flexible Display Applications

    Science.gov (United States)

    2013-11-14

    borosilicate glass flask with a glass stir bar . 2 mL of trioctylamine and 0.25 g of hexadecylamine were added to the flask. The flask was then sealed...thermocouple through the third septum monitored the reaction temperature while the stir bar maintained homogeneity of the solution. During the beginning of the...W.; Sahoo, Y.; Lee, K.; Prasad, P.; Cartwright, A.; Thapa, R.; US Patent App. 20, 021, Ed., 2008. (42) Hsieh, J., Tesis , Massachusetts Institute of

  14. Nuclear waste management and disposal

    International Nuclear Information System (INIS)

    Czibolya, L.

    1983-01-01

    The general demands for radioactive waste management, the key problem of nuclear fuel cycle are discussed. Various processes have been developed to solidify highly radioactive, long-lived wastes of the reprocessing plants in the form of borosilicate or phosphate glasses. Wastes of medium and low activity are generally solidified using either cement or bitumen or polyethylene as matrices. The alternatives of final waste disposal are reviewed according to French, Soviet, American, British, Swedish, Indian and Japanese experiences. (V.N.)

  15. Preparation of mesoporous carbon from fructose using zinc-based activators

    OpenAIRE

    Tutik Setianingsih; Indriana Kartini; Yateman Arryanto

    2015-01-01

    Mesoporous carbons were synthesized from fructose using activators of zinc silicate (ZS), zinc borate (ZB), and zinc borosilicate (ZBS). The synthesis involves 3 steps, including caramelization of sugar, carbonization of caramel, and washing of carbon to separate the activator from the carbon. The solid products were characterized by N2 gas adsorption-desorption, X-ray diffraction, FTIR spectrophotometry, and Transmission Electron Microscopy. The pore characterizations of the carbons in...

  16. Note: Anodic bonding with cooling of heat-sensitive areas

    DEFF Research Database (Denmark)

    Vesborg, Peter Christian Kjærgaard; Olsen, Jakob Lind; Henriksen, Toke Riishøj

    2010-01-01

    Anodic bonding of silicon to glass always involves heating the glass and device to high temperatures so that cations become mobile in the electric field. We present a simple way of bonding thin silicon samples to borosilicate glass by means of heating from the glass side while locally cooling heat......-sensitive areas from the silicon side. Despite the high thermal conductivity of silicon, this method allows a strong anodic bond to form just millimeters away from areas essentially at room temperature....

  17. Long-term leach rates of glasses containing actual waste

    International Nuclear Information System (INIS)

    Wiley, J.R.; LeRoy, J.H.

    1979-01-01

    Leach rates of borosilicate glasses that contained actual Savannah River Plant waste were measured. Leaching was done by water and by buffer solutions of pH 4, 7, and 9. Leach rates were then determined from the amount of 137 Cs, 90 Sr, and Pu released into the leach solutions. The cumulative fractions leached were fit to a mathematical model that included leaching by diffusion and glass dissolution

  18. The DWPF waste form qualification program

    International Nuclear Information System (INIS)

    Marra, S.L.; Plodinec, M.J.

    1994-01-01

    Prior to the introduction of radioactive feed into the Defense Waste Processing Facility for immobilization in borosilicate glass an extensive waste qualification program must be completed. The DWPF must demonstrate its ability to comply with the Waste Acceptance Product Specifications. This ability is being demonstrated through laboratory and pilot scale work and will be completed after the full operation of the DWPF using various simulated feeds

  19. Glass Ceramic Formulation Data Package

    Energy Technology Data Exchange (ETDEWEB)

    Crum, Jarrod V.; Rodriguez, Carmen P.; McCloy, John S.; Vienna, John D.; Chung, Chul-Woo

    2012-06-17

    A glass ceramic waste form is being developed for treatment of secondary waste streams generated by aqueous reprocessing of commercial used nuclear fuel (Crum et al. 2012b). The waste stream contains a mixture of transition metals, alkali, alkaline earths, and lanthanides, several of which exceed the solubility limits of a single phase borosilicate glass (Crum et al. 2009; Caurant et al. 2007). A multi-phase glass ceramic waste form allows incorporation of insoluble components of the waste by designed crystallization into durable heat tolerant phases. The glass ceramic formulation and processing targets the formation of the following three stable crystalline phases: (1) powellite (XMoO4) where X can be (Ca, Sr, Ba, and/or Ln), (2) oxyapatite Yx,Z(10-x)Si6O26 where Y is alkaline earth, Z is Ln, and (3) lanthanide borosilicate (Ln5BSi2O13). These three phases incorporate the waste components that are above the solubility limit of a single-phase borosilicate glass. The glass ceramic is designed to be a single phase melt, just like a borosilicate glass, and then crystallize upon slow cooling to form the targeted phases. The slow cooling schedule is based on the centerline cooling profile of a 2 foot diameter canister such as the Hanford High-Level Waste canister. Up to this point, crucible testing has been used for glass ceramic development, with cold crucible induction melter (CCIM) targeted as the ultimate processing technology for the waste form. Idaho National Laboratory (INL) will conduct a scaled CCIM test in FY2012 with a glass ceramic to demonstrate the processing behavior. This Data Package documents the laboratory studies of the glass ceramic composition to support the CCIM test. Pacific Northwest National Laboratory (PNNL) measured melt viscosity, electrical conductivity, and crystallization behavior upon cooling to identify a processing window (temperature range) for melter operation and cooling profiles necessary to crystallize the targeted phases in the

  20. Sulphate solubility and sulphate diffusion in oxide glasses: implications for the containment of sulphate-bearing nuclear wastes; Solubilite et cinetiques de diffusion des sulfates dans differents verres d'oxydes: application au conditionnement des dechets nucleaires sulfates

    Energy Technology Data Exchange (ETDEWEB)

    Lenoir, M.

    2009-09-15

    The thesis deals with sulphate solubility and sulphate diffusion in oxide glasses, in order to control sulphate incorporation and sulphate volatilization in nuclear waste glasses. It was conducted on simplified compositions, in the SiO{sub 2}-B{sub 2}O{sub 3}-R{sub 2}O (R = Li, Na, K, Cs), SiO{sub 2}-B{sub 2}O{sub 3}-BaO and V{sub 2}O{sub 5}-B{sub 2}O{sub 3}-BaO systems. These compositions allowed us to study the influence of the nature of network-modifying ions (Li{sup +}, Na{sup +}, K{sup +}, Cs{sup +} or Ba{sup 2+}) and also of former elements (Si, B, V), on structure and properties of glasses. Sulphate volatility is studied in sodium borosilicate melts using an innovative technique of sulphate quantitation with Raman spectroscopy. This technique is useful to obtain kinetic curves of sulphate volatilization. The establishment of a model to fit these curves leads to the determination of diffusion coefficients of sulphate. These diffusion coefficients can thus be compared to diffusion coefficients of other species, determined by other techniques and presented in the literature. They are also linked to diffusion coefficients in relation with the viscosity of the melts. Concerning sulphate solubility in glasses, it depends on glass composition and on the nature of sulphate incorporated. Sulphate incorporation in alkali borosilicate glasses leads to the formation of a sulphate layer floating on top of the melt. Sulphate incorporation in barium borosilicate and boro-vanadate glasses leads to the crystallization of sulphate species inside the vitreous matrix. Moreover, sulphate solubility is higher in these glasses than in alkali borosilicates. Finally, exchanges between cations present in glasses and cations present in the sulphate phase are also studied. (author)

  1. Étude de la dissolution de verres borosilicatés en présence de minéraux magnésiens modèles représentatifs des minéraux de l'argilite du Callovo-Oxfordien

    OpenAIRE

    Debure, Mathieu

    2012-01-01

    Borosilicate glasses dissolution has been studied in presence of magnesium minerals. Those minerals (dolomite, illite, smectite…) belong to the Callovo-Oxfordian (COx) claystone layer, studied in France as a potential site for nuclear waste disposal. Such minerals contain magnesium, an element able to sustain glass alteration when it is available in solution. In the confined media of the wastes disposal, thesolids reactivity controls the solution composition and can be the driving force of nu...

  2. Etudes par spectroscopie Raman et par RMN des verres du système B 2O 3SiO 2Li 2O

    Science.gov (United States)

    Brethous, Jean-Claude; Levasseur, Alain; Villeneuve, Gerard; Echegut, Patrick; Hagenmuller, Paul; Couzi, Michel

    1981-09-01

    A structural approach of glasses belonging to the B 2O 3SiO 2Li 2O system has been carried out by Raman spectroscopy. A complementary study of the boron environment by RMN was also realized. The glasses are formed by two separate phases containing respectively a borate and a silicate framework. This phenomenon has been confirmed by some SEM investigations. No presence of borosilicate chains has been established.

  3. DESIGN AND CONSTRUCTION OF A MEMBRANE REACTOR SILVER FOR THE STUDY OF OXYGEN PERMEABILITY

    OpenAIRE

    Cjuno H., Jesús A.; Barba R., Alejandro; Arroyo C., Juan

    2014-01-01

    To study the permeability of oxygen through a membrane of silver (thickness 0.13 mm) and the definition of parameters, it has designed and constructed a reactor formed by a cone silver membrane inserted into a cylindrical glass tube borosilicate. This assembly is assembled within a cylindrical thermostated oven electronically. The membrane reactor was conentado to an oxygen tank, and two peristaltic pump mercury manometer, enabling control of inflow of methanol, the temperature and internal p...

  4. Filtration via Conventional Glass Fiber Filters in 15N2 Tracer Assays Fails to Capture All Nitrogen-Fixing Prokaryotes

    OpenAIRE

    Deniz Bombar; Ryan W. Paerl; Ruth Anderson; Lasse Riemann

    2018-01-01

    Biological dinitrogen fixation (BNF) represents a major input of reduced nitrogen (N) to the oceans. Accurate direct measurements of BNF rates are crucial for reliably determining the biogeochemical significance of diazotrophy at local and global scales. Traditionally, borosilicate glass fiber filters (GF/F, Whatman) with a nominal pore size of 0.7 μm are used to collect suspended particles by filtration after incubations with added 15N2 tracer. We carried out BNF experiments in the Baltic Se...

  5. Development of a Contact Permeation Test Fixture and Method

    Science.gov (United States)

    2013-04-01

    potassium fluoride , 600 µL of 1 M hydrogen chloride, and 1 µL of the internal standard, was added to a borosilicate culture tube that contained the...Port Washington, NY) that had been prerinsed with 1 mL of ethyl acetate before it was transferred to a gas chromatography (GC) autosampler vial...measure the cumulative permeated mass. Analysis was conducted using gas chromatography with flame photometric detection (GC-FPD). Figure 4. An

  6. Fabrication of a LP01 to LP02 mode converter embedded in bulk glass using femtosecond direct inscription

    Science.gov (United States)

    Mellah, Hakim; Bérubé, Jean-Philippe; Vallée, Réal; Zhang, Xiupu

    2018-03-01

    In this paper, we demonstrate a fabrication of an integrated mode converter that converts LP01 to LP02 for the C-band. The mode converter was directly inscribed in the bulk of a borosilicate glass using a femtosecond laser. The converter has an insertion loss of less than 1 dB for the entire C-band, suggesting more than 80% conversion efficiency.

  7. The integrated melter off-gas treatment systems at the West Valley Demonstration Project

    International Nuclear Information System (INIS)

    Vance, R.F.

    1991-12-01

    The West Valley Demonstration project was established by an act of Congress in 1980 to solidify the high level radioactive liquid wastes produced from operation of the Western New York Nuclear Services Center from 1966 to 1972. The waste will be solidified as borosilicate glass. This report describes the functions, the controlling design criteria, and the resulting design of the melter off-gas treatment systems

  8. Diffusion of actinides in glasses containing simulated radioactive wastes

    International Nuclear Information System (INIS)

    Ivanov, I.A.; Sedov, V.M.; Gulin, A.N.; Shatkov, V.M.; Shashukov, E.A.

    1991-01-01

    Diffusion coefficients of radionuclides 237 Pu, 239 Pu and 241 Am in simulated alumina phosphate and alumina borosilicate glasses at temperatures lower than their transformation temperatures were determined. Actinides are known to be the least mobile elements. It is shown that crystallization of glasses leads to increasing 237 Np diffusion mobility. It is also shown that a rather small quantity of water absorbed by a crystallized alumina phosphate glass intensifies low-temperature migration of 237 Np. (author) 6 refs.; 2 tabs

  9. High-Level Waste System Process Interface Description

    International Nuclear Information System (INIS)

    D'Entremont, P.D.

    1999-01-01

    The High-Level Waste System is a set of six different processes interconnected by pipelines. These processes function as one large treatment plant that receives, stores, and treats high-level wastes from various generators at SRS and converts them into forms suitable for final disposal. The three major forms are borosilicate glass, which will be eventually disposed of in a Federal Repository, Saltstone to be buried on site, and treated water effluent that is released to the environment

  10. Impact Strength of Glass and Glass Ceramic

    Science.gov (United States)

    Bless, S.; Tolman, J.

    2009-12-01

    Strength of glass and glass ceramic was measured with a bar impact technique. High-speed movies show regions of tensile and compressive failure. The borosilicate glass had a compressive strength of at least 2.2 GPa, and the glass ceramic at least 4 GPa. However, the BSG was much stronger in tension than GC. In ballistic tests, the BSG was the superior armor.

  11. Testing and evaluation of the properties of various potential materials for immobilizing high activity waste. First annual report (1977)

    International Nuclear Information System (INIS)

    Malow, G.; Beran, V.; Lutze, W.; Marples, J.A.C.; Dalton, J.T.; Hall, A.R.; Hough, A.; Boult, K.A.

    1979-01-01

    Four borosilicate glasses and one Celsian glass ceramic were tested under strictly identical conditions. This report presents the results of the following test: (a) Leach testing of samples, in the as cast state, annealed at 800 0 C for up to 100 days; (b) Grain titration test of hydrolytic resistance (DIN 12111); (c) Examination of the glass structure and its changes due to thermal effects, differential thermal analysis, x ray diffraction analysis, scanning electron microscopy, microprobe analysis

  12. Dielectric and impedance spectroscopic studies of (Sr1–xPbx)TiO2 ...

    Indian Academy of Sciences (India)

    Administrator

    ⋅TiO2]–[2SiO2⋅B2O3]–5[K2O–. BaO] (0⋅0 ≤ x ≤ 0⋅4) with addition of 1 mol% Nb2O5. Perovskite strontium lead titanate in solid solution phase has been crystallized in borosilicate glassy matrix with suitable choice of composition and heat ...

  13. Stabilities of nuclear waste forms and their geochemical interactions in repositories

    International Nuclear Information System (INIS)

    White, W.B.

    1980-01-01

    The stabilities of high-level nuclear waste forms in a repository environment are briefly discussed. The advantages and disadvantages of such waste forms as borosilicate glass, supercalcine ceramics, and synthetic minerals are presented in context with the different rock types which have been proposed as possible host rocks for repositories. It is concluded that the growing geochemical evidence favors the use of a silicate rock repository because of the effectiveness of aluminosilicate rocks as chemical barriers for most radionuclides

  14. Boron nitride nanotubes as a reinforcement for brittle matrices

    Czech Academy of Sciences Publication Activity Database

    Tatarko, Peter; Grasso, S.; Porwal, H.; Saggar, Richa; Chlup, Zdeněk; Dlouhý, Ivo; Reece, M.J.

    2014-01-01

    Roč. 34, č. 14 (2014), s. 3339-3349 ISSN 0955-2219 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0068 EU Projects: European Commission(XE) 264526 - GLACERCO Institutional support: RVO:68081723 Keywords : Amorphous borosilicate glass * Boron nitride nanotubes * Composite * Toughening mechanisms * Scratch resistance Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 2.947, year: 2014

  15. Glasses and ceramics for immobilisation of radioactive wastes for disposal

    International Nuclear Information System (INIS)

    Johnson, K.D.B.; Marples, J.A.C.

    1979-05-01

    The U.K. Research Programme on Radioactive Waste Management includes the development of processes for the conversion of high level liquid reprocessing wastes from thermal and fast reactors to borosilicate glasses. The properties of these glasses and their behaviour under storage and disposal conditions have been examined. Methods for immobilising activity from other wastes by conversion to glass or ceramic forms is described. The U.K. philosophy of final solutions to waste management and disposal is presented. (author)

  16. UK program: glasses and ceramics for immobilization of radioactive wastes for disposal

    International Nuclear Information System (INIS)

    Johnson, K.D.B.

    1979-01-01

    The UK Research Program on Radioactive Waste Management includes the development of processes for the conversion of high-level-liquid-reprocessing wastes from thermal and fast reactors to borosilicate glasses. The properties of these glasses and their behavior under storage and disposal conditions have been examined. Methods for immobilizing activity from other wastes by conversion to glass or ceramic forms are described. The UK philosophy of final solutions to waste management and disposal is presented

  17. High-Level Waste System Process Interface Description

    Energy Technology Data Exchange (ETDEWEB)

    d' Entremont, P.D.

    1999-01-14

    The High-Level Waste System is a set of six different processes interconnected by pipelines. These processes function as one large treatment plant that receives, stores, and treats high-level wastes from various generators at SRS and converts them into forms suitable for final disposal. The three major forms are borosilicate glass, which will be eventually disposed of in a Federal Repository, Saltstone to be buried on site, and treated water effluent that is released to the environment.

  18. Measurement of damage velocities in impacts of transparent armor

    International Nuclear Information System (INIS)

    Anderson, Charles E Jr; Bigger, Rory P; Weiss, Carl E

    2014-01-01

    A series of impact experiments were conducted to examine the response of transparent material to ballistic impact. The experiments consisted of impacting 15 mm of borosilicate glass bonded to 9.5 mm of Lexan. The projectile was a 0.30-cal hard steel bullet designed specifically for the experiments. High-speed imaging of the impact event and post-test analysis quantified damage propagation and the rate of propagation.

  19. Measurement of damage velocities in impacts of transparent armor

    Science.gov (United States)

    Anderson, Charles E., Jr.; Bigger, Rory P.; Weiss, Carl E.

    2014-05-01

    A series of impact experiments were conducted to examine the response of transparent material to ballistic impact. The experiments consisted of impacting 15 mm of borosilicate glass bonded to 9.5 mm of Lexan. The projectile was a 0.30-cal hard steel bullet designed specifically for the experiments. High-speed imaging of the impact event and post-test analysis quantified damage propagation and the rate of propagation.

  20. Effet des terres rares sur la structure et l'altération des verres borosilicatés

    OpenAIRE

    Molières , Estelle

    2012-01-01

    This work is related to the question of the geological deep repository of high-level waste glass. These wastes include fission products and minor actinides, elements which can be simulated by rare earths. As new glass compositions could enable increased rare earth concentrations, it is crucial to know and understand rare earth impact on glass structure on the one hand, and on glass alteration kinetics or their incorporation into an altered layer. This work studied simplified borosilicate glas...

  1. The role of nuclear analytical techniques in the study of aqueous corrosion of glasses

    International Nuclear Information System (INIS)

    Trocellier, P.

    1984-01-01

    Direct observation of resonant nuclear reactions, backscattering spectrometry and X ray microanalysis with a nuclear microprobe were used to determine elementary depth profiles in the near surface region of leached glasses. Some computing programs required to interpretate the analytical information detected were built. Experimental conditions to characterize glass samples without secondary effects were defined; and the influence of some leaching parameters was studied to describe the first stages of aqueous corrosion of borosilicate glasses [fr

  2. Growth of the high reflectivity Bi 2O 3 glass films by atmospheric pressure halide CVD

    Science.gov (United States)

    Takeyama, T.; Takahashi, N.; Nakamura, T.; Ito, S.

    2004-09-01

    We reported the results of an investigation into the preparation of amorphous Bi 2O 3 onto borosilicate glass substrate by means of atmospheric pressure halide chemical vapor deposition using BiI 3 and oxygen as a source materials. Obtained thin films lower than 475 °C was amorphous and it was almost transparent in infrared region. But the amorphous films are iodine-containing Bi 2O 3, as results of analysis by XRD and XPS.

  3. Remote handling of canisters containing nuclear waste in glass at the Savannah River Plant

    International Nuclear Information System (INIS)

    Callan, J.E.

    1986-01-01

    The Defense Waste Processing Facility is being constructed at the Savannah River Plant at a cost of $870 million to immobilize the defense high-level radioactive waste. This radioactive waste is being added to borosilicate glass for later disposal in a federal repository. The borosilicate glass is poured into stainless steel canisters for storage. These canisters must be handled remotely because of their high radioactivity, up to 5000 R/h. After the glass has been poured into the canister which will be temporarily sealed, it is transferred to a decontamination cell and decontaminated. The canister is then transferred to the weld cell where a permanent cap is welded into place. The canisters must then be transported from the processing building to a storage vault on the plant until the federal repository is available. A shielded canister transporter (SCT) has been designed and constructed for this purpose. The design of the SCT vehicle allows the safe transport of a highly radioactive canister containing borosilicate glass weighing 2300 kg with a radiation level up to 5000 R/h from one building to another. The design provides shielding for the operator in the cab of the vehicle to be below 0.5 rem/h. The SCT may also be used to load the final shipping cask when the federal repository is ready to receive the canisters

  4. Liquidus temperature and chemical durability of selected glasses to immobilize rare earth oxides waste

    Science.gov (United States)

    Mohd Fadzil, Syazwani; Hrma, Pavel; Schweiger, Michael J.; Riley, Brian J.

    2015-10-01

    Pyroprocessing is are processing method for managing and reusing used nuclear fuel (UNF) by dissolving it in an electrorefiner with a molten alkali or alkaline earth chloride salt mixture while avoiding wet reprocessing. Pyroprocessing UNF with a LiCl-KCl eutectic salt releases the fission products from the fuel and generates a variety of metallic and salt-based species, including rare earth (RE) chlorides. If the RE-chlorides are converted to oxides, borosilicate glass is a prime candidate for their immobilization because of its durability and ability to dissolve almost any RE waste component into the glass matrix at high loadings. Crystallization that occurs in waste glasses as the waste loading increases may complicate glass processing and affect the product quality. This work compares three types of borosilicate glasses in terms of liquidus temperature (TL): the International Simple Glass designed by the International Working Group, sodium borosilicate glass developed by Korea Hydro and Nuclear Power, and the lanthanide aluminoborosilicate (LABS) glass established in the United States. The LABS glass allows the highest waste loadings (over 50 mass% RE2O3) while possessing an acceptable chemical durability.

  5. Testing and evaluation of solidified high-level waste forms

    International Nuclear Information System (INIS)

    Engelmann, C.

    1984-01-01

    The report describes research by several laboratories on the behaviour, in aqueous and salt environments, of borosilicate glass ceramics proposed for the solidification of nuclear wastes by the European Community. Results were obtained on inactive simulates, doped materials, and on borosilicate glass containing real radioactive waste. The influence of many important parameters were studied: leaching mode, nature of the leachant, pH, pressure, temperature, duration of the treatment, etc. The results of tests lasting for as little as a few hours or for as long as several hundred days, at temperatures up to 200 0 C or under pressures up to 200 bars, are presented. Numerous analytical techniques (ESCA, EMP, IRR, SEM, etc.) were used to determine the structure and the chemical composition of the altered layer developed by hydration at the glass surface. Information is also given on physical properties of the borosilicate glass: crystallization phase separation, alpha-irradiation stability, mechanical and thermal stability, etc. Finally, preliminary results on the structure and composition of hollandite ceramics are given

  6. Structural role of molybdenum in nuclear glasses: an EXAFS study

    International Nuclear Information System (INIS)

    Calas, G.; Le Grand, M.; Galoisy, L.; Ghaleb, D.

    2003-01-01

    The Mo environment has been investigated in inactive nuclear glasses using extended X-ray absorption spectroscopy (XAS). Mo is present in a tetrahedron coordinated to oxygen in the form of molybdate groups [MoO 4 ] 2- (d(Mo-O)=1.78 A). This surrounding is not affected by the presence of noble metal phases in the nuclear glass. Relying on the XAS results, on the bond-valence model and on molecular dynamics simulations of a simplified borosilicate model glass, we show that these groups are not directly linked to the borosilicate network but rather located within alkali and alkaline-earth rich domains in the glass. This specific location in the glass network is a way to understand the low solubility of Mo in glasses melted under oxidizing conditions. It also explains the possible phase separation of a yellow phase enriched in alkali molybdates in molten nuclear glasses or the nucleation of calcium molybdates during thermal aging of these glasses. Boron coordination changes in the molten and the glassy states may explain the difference in the composition of the crystalline molybdates, as they exert a direct influence on the activity of alkalis in borosilicate glasses and melts

  7. Silica based gel as a potential waste form for high level waste from fuel reprocessing

    International Nuclear Information System (INIS)

    Ford, C.E.; Dempster, T.J.; Melling, P.J.

    1983-10-01

    To assess the feasibility of safe disposal of high-level radioactive waste as synthetic clay, or material that would react with ground water to form clay, experiments have been carried out to determine the hydrothermal crystallisation and leaching behaviour of silica based gels fired at 900 deg C. Crystallisation rates at a pressure of 500 bars and at temperatures below 400 deg C are negligible and this more or less precludes pre-disposal production of synthetic clay on the scale required. Leaching experiments suggest that the leach rates of Cs from gels by distilled water are higher than those of boro-silicate glasses and SYNROC at the lower temperatures that would be preferred for geological storage. However, amounts of bulk dissolution of gels may be lower than those of boro-silicate glasses. The initial leaching behaviour of gels might be considerably improved by hot compaction at 900 to 1000 deg C. Consideration of likely waste form dissolution behaviour in a repository environment suggests that gels of appropriate composition might perform as well as, or better than, boro-silicate glasses. A novel hypothetical plant is described that could produce the gel waste form on the scale required on a more or less continuous basis. (author)

  8. Performance testing of waste forms in a tuff environment

    International Nuclear Information System (INIS)

    Oversby, V.M.

    1983-11-01

    This paper describes experimental work conducted to establish the chemical composition of water which will have reacted with Topopah Spring Member tuff prior to contact with waste packages. The experimental program to determine the behavior of spent fuel and borosilicate glass in the presence of this water is then described. Preliminary results of experiments using spent fuel segments with defects in the Zircaloy cladding are presented. Some results from parametric testing of a borosilicate glass with tuff and 304L stainless steel are also discussed. Experiments conducted using Topopah Spring tuff and J-13 well water have been conducted to provide an estimate of the post-emplacement environment for waste packages in a repository at Yucca Mountain. The results show that emplacement of waste packages should cause only small changes in the water chemistry and rock mineralogy. The changes in environment should not have any detrimental effects on the performance of metal barriers or waste forms. The NNWSI waste form testing program has provided preliminary results related to the release rate of radionuclides from the waste package. Those results indicate that release rates from both spent fuel and borosilicate glass should be below 1 part in 10 5 per year. Future testing will be directed toward making release rate testing more closely relevant to site specific conditions. 17 references, 7 figures

  9. Taylor impact of glass rods

    International Nuclear Information System (INIS)

    Willmott, G.R.; Radford, D.D.

    2005-01-01

    The deformation and fracture behavior of soda-lime and borosilicate glass rods was examined during classic and symmetric Taylor impact experiments for impact pressures to 4 and 10 GPa, respectively. High-speed photography and piezoresistive gauges were used to measure the failure front velocities in both glasses, and for impact pressures below ∼2 GPa the failure front velocity increases rapidly with increasing pressure. As the pressure was increased above ∼3 GPa, the failure front velocities asymptotically approached maximum values between the longitudinal and shear wave velocities of each material; at ∼4 GPa, the average failure front velocities were 4.7±0.5 and 4.6±0.5 mm μs -1 for the soda-lime and borosilicate specimens, respectively. The observed mechanism of failure in these experiments involved continuous pressure-dependent nucleation and growth of microcracks behind the incident wave. As the impact pressure was increased, there was a decrease in the time to failure. The density of cracks within the failed region was material dependent, with the more open-structured borosilicate glass showing a larger fracture density

  10. Contributions of vitreous natural analogs to the investigation of long-term nuclear glass behavior

    International Nuclear Information System (INIS)

    Techer, I.

    1999-01-01

    This study assesses the extend of the analogy between the alteration behavior in water and in a moist clay environment of aluminosilicate volcanic glass and alumino-borosilicate nuclear containment glass. Basaltic glass alteration in water initially occurs by hydrolysis processes with an activation energy on the order of 73 kJ.mol -1 . As the reaction progresses, the alteration rate drops by over four orders of magnitude from the initial rate r 0 , The alteration kinetics are not governed by the alteration solution chemistry alone, the glass alteration film appears to have a major role as a diffusion barrier limiting the transfer of reaction species and products. All these aspects highlight the behavioral analogy between basaltic glass and nuclear borosilicate glass in aqueous media. Conversely, the alteration reaction of obsidian-type volcanic glass involves other mechanisms than those governing the dissolution of borosilicate glass. Basaltic glass alteration is also examined in the presence of a clay environmental material, in a study of the natural basaltic glass and argillaceous pelites system of the Salagou basin in southern France, in an approach combining mineralogical, chemical and isotopic data to assess the interactions between a basaltic glass and the argillaceous pelites. Laboratory leach test results with basaltic glass and measured data for the Salagou glass in its natural environment are modeled using a code implementing a kinetic law coupling diffusive transfer of dissolved silica with a reaction affinity law. (author)

  11. Conceptual process for immobilizing defense high level wastes in SYNROC-D

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    It is believed that the immobilization of defense wastes in SYNROC-D possesses important advantages over an alternative process which involves immobilizing the sludges in borosilicate glass. (1) It is possible to immobilize about 3 times the weight of sludge in a given volume of SYNROC-D as compared to borosilicate glass. The costs of fabrications, transport and ultimate geologic storage are correspondingly reduced; (2) the mineral assemblage of SYNROC-D is vastly more stable in the presence of groundwaters than are borosilicate glasses. The long-lived actinide elements, in particular, are immobilized much more securely in SYNROC-D than in glass; and (3) SYNROC-D is composed of thermodynamically compatible phases which possess crystal structures identical to those of natural minerals which are known to have survived in geological environments at elevated pressures and temperatures for periods of 500 to 2000 million years and to have retained radioactive elements quantitatively for these periods despite strong radiation damage. It is this evidence, provided by nature herself, which can demonstrate to the community that the shorter times required for radwaste immobilization under the much less extreme pressure, temperature conditions present in a suitable geological repository can be successfully achieved. Glass, as a waste-form, is intrinsically incapable of providing this assurance

  12. Aluminum elution and precipitation in glass vials: effect of pH and buffer species.

    Science.gov (United States)

    Ogawa, Toru; Miyajima, Makoto; Wakiyama, Naoki; Terada, Katsuhide

    2015-02-01

    Inorganic extractables from glass vials may cause particle formation in the drug solution. In this study, the ability of eluting Al ion from borosilicate glass vials, and tendencies of precipitation containing Al were investigated using various pHs of phosphate, citrate, acetate and histidine buffer. Through heating, all of the buffers showed that Si and Al were eluted from glass vials in ratios almost the same as the composition of borosilicate glass, and the amounts of Al and Si from various buffer solutions at pH 7 were in the following order: citrate > phosphate > acetate > histidine. In addition, during storage after heating, the Al concentration at certain pHs of phosphate and acetate buffer solution decreased, suggesting the formation of particles containing Al. In citrate buffer, Al did not decrease in spite of the high elution amount. Considering that the solubility profile of aluminum oxide and the Al eluting profile of borosilicate glass were different, it is speculated that Al ion may be forced to leach into the buffer solution according to Si elution on the surface of glass vials. When Al ions were added to the buffer solutions, phosphate, acetate and histidine buffer showed a decrease of Al concentration during storage at a neutral range of pHs, indicating the formation of particles containing Al. In conclusion, it is suggested that phosphate buffer solution has higher possibility of forming particles containing Al than other buffer solutions.

  13. Development, evaluation, and selection of candidate high-level waste forms

    International Nuclear Information System (INIS)

    Bernadzikowski, T.A.; Allender, J.S.; Gordon, D.E.; Gould, T.H. Jr.

    1982-01-01

    The seven candidate waste forms, evaluated as potential media for the immobilization and gelogic disposal of high-level nuclear wastes were borosilicate glass, SYNROC, tailored ceramic, high-silica glass, FUETAP concrete, coated sol-gel particles, and glass marbles in a lead matrix. The evaluation, completed on August 1, 1981, combined preliminary waste form evaluations conducted at Department of Energy (DOE) defense waste-sites and at independent laboratories, peer review assessments, a product performance evaluation, and a processability analysis. Based on the combined results of these four inputs, two of the seven forms, borosilicate glass and a titanate-based ceramic, SYNROC, were selected as the reference and alternative forms, respectively, for continued development and evaluation in the National HLW Program. The borosilicate glass and ceramic forms were further compared during FY-1982 on the basis of risk assessments, cost comparisons, properties comparisons, and conformance with proposed regulatory and repository criteria. Both the glass and ceramic forms are viable candidates for use at DOE defense HLW sites; they are also candidates for immobilization of commercial reprocessing wastes. This paper describes the waste form screening process, discusses each of the four major inputs considered in the selection of the two forms in 1981, and presents a brief summary of the comparisons of the two forms during 1982 and the selection process to determine the final form for SRP defense HLW

  14. Contributions of vitreous natural analogs to the investigation of long-term nuclear glass behavior; Apports des analogues naturels vitreux a la validation des codes de prediction du comportement a long terme des verres nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Techer, I

    1999-07-01

    This study assesses the extend of the analogy between the alteration behavior in water and in a moist clay environment of aluminosilicate volcanic glass and alumino-borosilicate nuclear containment glass. Basaltic glass alteration in water initially occurs by hydrolysis processes with an activation energy on the order of 73 kJ.mol{sup -1}. As the reaction progresses, the alteration rate drops by over four orders of magnitude from the initial rate r{sub 0}, The alteration kinetics are not governed by the alteration solution chemistry alone, the glass alteration film appears to have a major role as a diffusion barrier limiting the transfer of reaction species and products. All these aspects highlight the behavioral analogy between basaltic glass and nuclear borosilicate glass in aqueous media. Conversely, the alteration reaction of obsidian-type volcanic glass involves other mechanisms than those governing the dissolution of borosilicate glass. Basaltic glass alteration is also examined in the presence of a clay environmental material, in a study of the natural basaltic glass and argillaceous pelites system of the Salagou basin in southern France, in an approach combining mineralogical, chemical and isotopic data to assess the interactions between a basaltic glass and the argillaceous pelites. Laboratory leach test results with basaltic glass and measured data for the Salagou glass in its natural environment are modeled using a code implementing a kinetic law coupling diffusive transfer of dissolved silica with a reaction affinity law. (author)

  15. Wettability measurement under high P-T conditions using X-ray imaging with application to the brine-supercritical CO2 system

    Science.gov (United States)

    Chaudhary, Kuldeep; Guiltinan, Eric J.; Cardenas, M. Bayani; Maisano, Jessica A.; Ketcham, Richard A.; Bennett, Philip C.

    2015-09-01

    We present a new method for measuring wettability or contact angle of minerals at reservoir pressure-temperature conditions using high-resolution X-ray computed tomography (HRXCT) and radiography. In this method, a capillary or a narrow slot is constructed from a mineral or a rock sample of interest wherein two fluids are allowed to form an interface that is imaged using X-rays. After some validation measurements at room pressure-temperature conditions, we illustrate this method by measuring the contact angle of CO2-brine on quartz, muscovite, shale, borosilicate glass, polytetrafluoroethylene (PTFE or Teflon), and polyether ether ketone (PEEK) surfaces at 60-71°C and 13.8-22.8 MPa. At reservoir conditions, PTFE and PEEK surfaces were found to be CO2-wet with contact angles of 140° and 127°, respectively. Quartz and muscovite were found to be water-wet with contact angles of 26° and 58°, respectively, under similar conditions. Borosilicate glass-air-brine at room conditions showed strong water-wet characteristics with a contact angle of 9°, whereas borosilicate glass-CO2-brine at 13.8 MPa and 60°C showed a decrease in its water-wetness with contact angle of 54°. This method provides a new application for X-ray imaging and an alternative to other methods.

  16. Extended Development Work to Validate a HLW Calcine Waste Form via INL's Cold Crucible Induction Melter

    Energy Technology Data Exchange (ETDEWEB)

    James A. King; Vince Maio

    2011-09-01

    To accomplish calcine treatment objectives, the Idaho Clean-up Project contractor, CWI, has chosen to immobilize the calcine in a glass-ceramic via the use of a Hot-Isostatic-Press (HIP); a treatment selection formally documented in a 2010 Record of Decision (ROD). Even though the HIP process may prove suitable for the calcine as specified in the ROD and validated in a number of past value engineering sessions, DOE is evaluating back-up treatment methods for the calcine as a result of the technical, schedule, and cost risk associated with the HIPing process. Consequently DOE HQ has requested DOE ID to make INL's bench-scale cold-crucible induction melter (CCIM) available for investigating its viability as a process alternate to calcine treatment. The waste form is the key component of immobilization of radioactive waste. Providing a solid, stable, and durable material that can be easily be stored is the rationale for immobilization of radioactive waste material in glass, ceramic, or glass-ceramics. Ceramic waste forms offer an alternative to traditional borosilicate glass waste forms. Ceramics can usually accommodate higher waste loadings than borosilicate glass, leading to smaller intermediate and long-term storage facilities. Many ceramic phases are known to possess superior chemical durability as compared to borosilicate glass. However, ceramics are generally multiphase systems containing many minor phase that make characterization and prediction of performance within a repository challenging. Additionally, the technologies employed in ceramic manufacture are typically more complex and expensive. Thus, many have proposed using glass-ceramics as compromise between in the more inexpensive, easier to characterize glass waste forms and the more durable ceramic waste forms. Glass-ceramics have several advantages over traditional borosilicate glasses as a waste form. Borosilicate glasses can inadvertently devitrify, leading to a less durable product that could

  17. Evaluation of Microflow Digital Imaging Particle Analysis for Sub-Visible Particles Formulated with an Opaque Vaccine Adjuvant.

    Directory of Open Access Journals (Sweden)

    Grant E Frahm

    Full Text Available Microflow digital imaging (MDI has become a widely accepted method for assessing sub-visible particles in pharmaceutical formulations however, to date; no data have been presented on the utility of this methodology when formulations include opaque vaccine adjuvants. This study evaluates the ability of MDI to assess sub-visible particles under these conditions. A Fluid Imaging Technologies Inc. FlowCAM® instrument was used to assess a number of sub-visible particle types in solution with increasing concentrations of AddaVax™, a nanoscale squalene-based adjuvant. With the objective (10X used and the limitations of the sensor resolution, the instrument was incapable of distinguishing between sub-visible particles and AddaVax™ droplets at particle sizes less than 5 μm. The instrument was capable of imaging all particle types assessed (polystyrene beads, borosilicate glass, cellulose, polyethylene protein aggregate mimics, and lysozyme protein aggregates at sizes greater than 5 μm in concentrations of AddaVax™ up to 50% (vol:vol. Reduced edge gradients and a decrease in measured particle sizes were noted as adjuvant concentrations increased. No significant changes in particle counts were observed for polystyrene particle standards and lysozyme protein aggregates, however significant reductions in particle counts were observed for borosilicate (80% of original and cellulose (92% of original particles. This reduction in particle counts may be due to the opaque adjuvant masking translucent particles present in borosilicate and cellulose samples. Although the results suggest that the utility of MDI for assessing sub-visible particles in high concentrations of adjuvant may be highly dependent on particle morphology, we believe that further investigation of this methodology to assess sub-visible particles in challenging formulations is warranted.

  18. Electrical conductivity of oxides from molten state to glassy. Effect on the incorporation of RuO{sub 2} particles; Conductivite electrique des verres et fontes d'oxides. Effets de l'incorporation de particules RuO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Simonnet, C

    2004-07-01

    This study concerns the electrical conductivity of oxides from molten state to glassy state and, in particular, the effect of the incorporation of RuO{sub 2} particles in the context of vitrification of radioactive waste. The material of interest in the nuclear field is basically a viscous or vitreous borosilicate containing a dispersion of RuO{sub 2} microcrystals. A very simple model of this heterogeneous material has been studied in particular (SiO{sub 2}, B{sub 2}O{sub 3}, Na{sub 2}O, RuO{sub 2}). An original method of impedance measurement in the liquid at high temperature yields reliable electrical conductivity values over a temperature range covering the liquid and vitreous phases of the borosilicates studied. In the borosilicate matrix, alkaline transport is mainly responsible for the ionic conduction. The temperature dependence of the conductivity may thus be represented by an equation combining a VFT law and an Arrhenius law to represent the electrical conductivity above and below T{sub g}. Beyond a critical volume fraction V{sub c} {approx} 0.01 of RuO{sub 2}, an electronic contribution is added to the ionic contribution of the matrix and the electrical conductivity increases significantly with the RuO{sub 2} content. This effect is described in terms of electrical percolation of the particle network. An electronic mechanism by tunnel transfer between particles is demonstrated. A mathematical model is developed to describe this mechanism in the solid composite. Beyond T{sub g}, conduction by the tunnel effect persists and the partial solubilization of RuO{sub 2} appears to be mainly responsible for the significant increase in electronic conductivity with the temperature. (author)

  19. Characterization of Fast-Scan Cyclic Voltammetric Electrodes Using Paraffin as an Effective Sealant with In Vitro and In Vivo Applications.

    Science.gov (United States)

    Ramsson, Eric S; Cholger, Daniel; Dionise, Albert; Poirier, Nicholas; Andrus, Avery; Curtiss, Randi

    2015-01-01

    Fast-scan cyclic voltammetry (FSCV) is a powerful technique for measuring sub-second changes in neurotransmitter levels. A great time-limiting factor in the use of FSCV is the production of high-quality recording electrodes; common recording electrodes consist of cylindrical carbon fiber encased in borosilicate glass. When the borosilicate is heated and pulled, the molten glass ideally forms a tight seal around the carbon fiber cylinder. It is often difficult, however, to guarantee a perfect seal between the glass and carbon. Indeed, much of the time spent creating electrodes is in an effort to find a good seal. Even though epoxy resins can be useful in this regard, they are irreversible (seals are permanent), wasteful (epoxy cannot be reused once hardener is added), hazardous (hardeners are often caustic), and require curing. Herein we characterize paraffin as an electrode sealant for FSCV microelectrodes. Paraffin boasts the advantages of near-immediate curing times, simplicity in use, long shelf-life and stable waterproof seals capable of withstanding extended cycling. Borosilicate electrode tips were left intact or broken and dipped in paraffin embedding wax. Excess wax was removed from the carbon surface with xyelenes or by repeated cycling at an extended waveform (-0.4 to 1.4V, 400 V/s, 60 Hz). Then, the waveform was switched to a standard waveform (-0.4 to 1.3V, 400 V/s, 10 Hz) and cycled until stable. Wax-sealing does not inhibit electrode sensitivity, as electrodes detected linear changes in dopamine before and after wax (then xylenes) exposure. Paraffin seals are intact after 11 days of implantation in the mouse, and still capable of measuring transient changes in in vivo dopamine. From this it is clear that paraffin wax is an effective sealant for FSCV electrodes that provides a convenient substitute to epoxy sealants.

  20. Nuclear waste disposal: perspective of a geochemist

    International Nuclear Information System (INIS)

    Sengupta, Pranesh; Dey, G.K.

    2011-01-01

    Satisfying the growing requirement in an environment friendly way is one of the most important tasks we need to accomplish these days. Considering the restricted non-renewable energy resources and limited technological progresses achieved in the renewable energy sectors in India, nuclear energy appears to be one of the most lucrative solutions towards the forthcoming energy crisis. Successful implementation of nuclear energy program however requires careful execution of high level nuclear waste management activities. One very important aspect of this process is to identify and develop suitable inert matrix(ces) for conditioning of nuclear waste(s) using natural analogue studies. And this establishes the very vital linkage between geochemical studies and nuclear waste immobilization. One good example of such an interdisciplinary approach can be seen in the methodologies adopted for immobilization of sulfate bearing high level nuclear wastes (SO 4 -HLW). It has been reported on several occasions that sulfur-rich melt get separated from silicate melt within magma chamber. Similar process has also been witnessed within vitrification furnaces whenever an attempt has been made to condition SO 4 -HLW within borosilicate glass matrices. Since such liquid-liquid phase separation leads to multiple difficulties in connection to radionuclide immobilization and plant scale vitrification processes, solutions were sought from natural analogue studies. Such as integrated approach ultimately resulted in establishing two different methodologies e.g. (i) modifying the borosilicate network through introduction of Ba 2+ cation; a process being followed in India and (ii) using phosphatic melt as a host instead of borosilicate melt; a process being followed in Russia. Detail of these two routes and the geochemical linkage in nuclear waste immobilization will be discussed.(author)

  1. Characterization of Fast-Scan Cyclic Voltammetric Electrodes Using Paraffin as an Effective Sealant with In Vitro and In Vivo Applications.

    Directory of Open Access Journals (Sweden)

    Eric S Ramsson

    Full Text Available Fast-scan cyclic voltammetry (FSCV is a powerful technique for measuring sub-second changes in neurotransmitter levels. A great time-limiting factor in the use of FSCV is the production of high-quality recording electrodes; common recording electrodes consist of cylindrical carbon fiber encased in borosilicate glass. When the borosilicate is heated and pulled, the molten glass ideally forms a tight seal around the carbon fiber cylinder. It is often difficult, however, to guarantee a perfect seal between the glass and carbon. Indeed, much of the time spent creating electrodes is in an effort to find a good seal. Even though epoxy resins can be useful in this regard, they are irreversible (seals are permanent, wasteful (epoxy cannot be reused once hardener is added, hazardous (hardeners are often caustic, and require curing. Herein we characterize paraffin as an electrode sealant for FSCV microelectrodes. Paraffin boasts the advantages of near-immediate curing times, simplicity in use, long shelf-life and stable waterproof seals capable of withstanding extended cycling. Borosilicate electrode tips were left intact or broken and dipped in paraffin embedding wax. Excess wax was removed from the carbon surface with xyelenes or by repeated cycling at an extended waveform (-0.4 to 1.4V, 400 V/s, 60 Hz. Then, the waveform was switched to a standard waveform (-0.4 to 1.3V, 400 V/s, 10 Hz and cycled until stable. Wax-sealing does not inhibit electrode sensitivity, as electrodes detected linear changes in dopamine before and after wax (then xylenes exposure. Paraffin seals are intact after 11 days of implantation in the mouse, and still capable of measuring transient changes in in vivo dopamine. From this it is clear that paraffin wax is an effective sealant for FSCV electrodes that provides a convenient substitute to epoxy sealants.

  2. Defense Waste Processing Facility: a remote process for solidification of Savannah River Plant high level waste

    International Nuclear Information System (INIS)

    Maher, R.; Shafranek, L.F.; Kelley, J.A.; Zeyfang, R.W.; Lethco, A.J.

    1982-03-01

    The Department of Energy is proposing that a Defense Waste Processing Facility be built at the Savannah River Plant (SRP) to remotely process and immobilize high level radioactive waste produced at the site. Research, development, and design of the facility is being provided by a multidisciplined task force of personnel from the Du Pont Company which designed, built and has operated SRP since 1950. This remotely operated facility will immobilize 28 million gallons of high level waste now stored in tanks, plus the waste to be generated from continued reprocessing operations. Borosilicate glass has been selected as the reference waste form for the immobilization process

  3. Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries

    Science.gov (United States)

    Doherty, J.P.; Marek, J.C.

    1987-02-25

    A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper(II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the original organic compounds, is subsequently blended with high level radioactive sludge land transferred to a vitrification facility for processing into borosilicate glass for long-term storage. 2 figs., 3 tabs.

  4. Inactivation of bacterial contaminants in drinking water using a novel batch-process TiO2-assisted solar photocatalytic disinfection (SPC-DIS) reactor for use in developing countries

    Energy Technology Data Exchange (ETDEWEB)

    McGuigan, K. G.; Duffy, E. F.; Al Touati, F.; Kehoe, S. C.; McLoughlin, O. A.; Gill, L. W.; Gernjak, W.; Oller, I.; Maldonado, M. I.; Malato, S.; Reed, R. H.

    2004-07-01

    The technical feasibility and performance of photocatalytic TiO2 coatings in batch-process solar disinfection (SODIS) reactors to improve potability of drinking water in developing countries have been studied. Borosilicate glass and PET plastic SODIS reactor fitted with flexible plastic inserts coated with TiO2 powder were shown to be 20% and 25% more effective, respectively, than standard SODIS reactors for the inactivation of E. coli K12 . Approximately 550J is required per litre of water to produce each 1-long-unit reduction in bacterial population within SPC-DIS reactors of the design described in this study. (Author) 14 refs.

  5. Hanford Waste Vitrification Plant full-scale feed preparation testing with water and process simulant slurries

    International Nuclear Information System (INIS)

    Gaskill, J.R.; Larson, D.E.; Abrigo, G.P.

    1996-03-01

    The Hanford Waste Vitrification Plant was intended to convert selected, pretreated defense high-level waste and transuranic waste from the Hanford Site into a borosilicate glass. A full-scale testing program was conducted with nonradioactive waste simulants to develop information for process and equipment design of the feed-preparation system. The equipment systems tested included the Slurry Receipt and Adjustment Tank, Slurry Mix Evaporator, and Melter-Feed Tank. The areas of data generation included heat transfer (boiling, heating, and cooling), slurry mixing, slurry pumping and transport, slurry sampling, and process chemistry. 13 refs., 129 figs., 68 tabs

  6. High-frequency characteristics of glass/ceramic composite and alumina multilayer structures

    International Nuclear Information System (INIS)

    Niwa, K.; Suzuki, H.; Yokoyama, H.; Kamechara, N.; Tsubone, K.; Tanisawa, H.; Sugiki, H.

    1990-01-01

    This paper reports the transmission characteristics of glass/ceramic composite (borosilicate glass/alumina) and alumina multilayer structures examined. The triplate stripline formed in the glass/ceramic multilayer shows low conductor and dielectric loss. Alumina multilayer, however, has twice the transmission loss at 10 GHz, because the resistivity of W in the alumina multilayer is higher than the Cu in the glass/ceramic multilayer. Crosstalk between striplines in the glass/ceramics is less than -80 dB up to 11 GHz and 9 GHz for alumina

  7. Transmission of fast highly charged ions through straight and tapered glass capillaries

    International Nuclear Information System (INIS)

    Ayyad, Asma M; Keerthisinghe, D; Kayani, A; Tanis, J A; Dassanayake, B S; Ikeda, T

    2013-01-01

    The transmission of 1 and 3 MeV protons through a borosilicate straight glass capillary and a tapered glass capillary was investigated. The straight capillary had a diameter of ∼0.18 mm and a length of ∼14.4 mm, while the tapered capillary had an inlet diameter of ∼0.71 mm, an outlet diameter of ∼0.10 mm and a length of ∼28 mm. The results show that the 1 and 3 MeV protons traverse through both samples without energy loss, while the tapered capillary showed better transmission than the straight capillary. (paper)

  8. Understanding of the mechanical and structural changes induced by alpha particles and heavy ions in the French simulated nuclear waste glass

    International Nuclear Information System (INIS)

    Karakurt, G.; Abdelouas, A.; Guin, J.-P.; Nivard, M.; Sauvage, T.; Paris, M.; Bardeau, J.-F.

    2016-01-01

    Borosilicate glasses are considered for the long-term confinement of high-level nuclear wastes. External irradiations with 1 MeV He + ions and 7 MeV Au 5+ ions were performed to simulate effects produced by alpha particles and by recoil nuclei in the simulated SON68 nuclear waste glass. To better understand the structural modifications, irradiations were also carried out on a 6-oxides borosilicate glass, a simplified version of the SON68 glass (ISG glass). The mechanical and macroscopic properties of the glasses were studied as function of the deposited electronic and nuclear energies. Alpha particles and gold ions induced a volume change up to −0.7% and −2.7%, respectively, depending on the glass composition. Nano-indentations tests were used to determine the mechanical properties of the irradiated glasses. A decrease of about −22% to −38% of the hardness and a decrease of the reduced Young's modulus by −8% were measured after irradiations. The evolution of the glass structure was studied by Raman spectroscopy, and also 11 B and 27 Al Nuclear Magnetic Resonance (MAS-NMR) on a 20 MeV Kr irradiated ISG glass powder. A decrease of the silica network connectivity after irradiation with alpha particles and gold ions is deduced from the structural changes observations. NMR spectra revealed a partial conversion of BO 4 to BO 3 units but also a formation of AlO 5 and AlO 6 species after irradiation with Kr ions. The relationships between the mechanical and structural changes are also discussed. - Highlights: • Mechanical and structural properties of two borosilicate glass compositions irradiated with alpha particles and heavy ions were investigated. • Both kinds of particles induced a decrease of the hardness, reduced Young's modulus and density. • Electronic and nuclear interactions are responsible for the changes observed. • The evolution of the mechanical properties under irradiation is linked to the changes occured in the

  9. Ferrule material dependence of axial force sensitivity of a tunable optical frequency filter made of fiber fabry-perot etalon

    Science.gov (United States)

    Tateda, Mitsuhiro; Dong, Mohan

    2011-01-01

    Fiber Fabry-Perot etalon (FFPE) is a device designed as an optical frequency filter, and its transmission characteristics change depending on force and temperature. In this paper, axial force sensitivity of three types of FFPE is investigated, whose ferrule materials have different Young's modulus. Force sensitivity of an FFPE whose ferrule material is borosilicate glass was found to be 2.7 GHz/N, while those of FFPEs with glass ceramics and zirconium oxide ferrules were 1.7 and 0.8 GHz/N, respectively. Thus, the theoretical expectation is confirmed experimentally that the axial force sensitivity of FFPE is inversely proportional to Young's modulus of the ferrule material.

  10. Origins of Discrepancies Between Kinetic Rate Law Theory and Experiments in the Na2O-B2O3-SiO2 System

    International Nuclear Information System (INIS)

    McGrail, B. PETER; Icenhower, Jonathan P.; Rodriguez, Elsa A.; McGrail, B.P.; Cragnolino, G.A.

    2002-01-01

    Discrepancies between classical kinetic rate law theory and experiment were quantitatively assessed and found to correlate with macromolecular amorphous separation in the sodium borosilicate glass system. A quantitative reinterpretation of static corrosion data and new SPFT data shows that a recently advanced protective surface layer theory fails to describe the observed dissolution behavior of simple and complex silicate glasses under carefully controlled experimental conditions. The hypothesis is shown to be self-inconsistent in contrast with a phase separation model that is in quantitative agreement with experiments

  11. Optical devices in adverse environments; Proceedings of the Meeting, Cannes, France, Nov. 19, 20, 1987

    International Nuclear Information System (INIS)

    Greenwell, R.A.

    1988-01-01

    Recent advances in the design of fiber-optic devices, test equipment, optical sensors, and lasers for operation in hostile environments are discussed in reviews and reports. Topics examined include radiation effects on optical fibers, the effect of H2 treatment and water content on the recovery of undoped core fibers after pulsed and continuous irradiation, the NATO test program for optical fibers and components, alpha-irradiation damage to borosilicate glasses, high-reliability optical components for undersea light-wave systems, the behavior of Si optoelectronic components under gamma irradiation, optical devices and sensors of special-purpose fibers, and a fiber-optic microprobe for interferometric measurements in generators

  12. Ultra Accelerated Testing of PV Module Components

    Energy Technology Data Exchange (ETDEWEB)

    Pitts, J. R.; King, D. E.; Bingham, C.; Czanderna, A. W.

    1998-10-28

    Using concentrated natural sunlight at the NREL High Flux Solar Furnace, we have exposed several materials to acceleration factors of up to 400 times the normal outdoor UV exposure dose. This accelerated rate allows the exposure of materials such that a year of outdoor exposure can be simulated in about 5 hours. We have studied the solarization of cerium containing glass, the degradation of ethylene vinyl acetate laminated between borosilicate glass, and the yellowing of standard polystyrene test coupons. The first two candidates are of interest to the photovoltaics (PV) program, and the last candidate material is a widely used dosimeter for ultra violet (UV) exposure in accelerated weathering chambers

  13. Description of a ceramic waste form and canister for Savannah River Plant high-level waste

    International Nuclear Information System (INIS)

    Butler, J.L.; Allender, J.S.; Gould, T.H. Jr.

    1982-04-01

    A canistered ceramic waste form for possible immobilization of Savannah River Plant (SRP) high-level radioactive wastes is described. Characteristics reported for the form include waste loading, chemical composition, heat content, isotope inventory, mechanical and thermal properties, and leach rates. A conceptual design of a potential production process for making this canistered form are also described. The ceramic form was selected in November 1981 as the primary alternative to the reference waste form, borosilicate glass, for making a final waste form decision for SRP waste by FY-1983. 11 tables

  14. DWPF glass transition temperatures: What they are and why they are important

    International Nuclear Information System (INIS)

    Marra, S.L.; Jantzen, C.M.; Ramsey, A.A.

    1991-01-01

    The Defense Waste Processing Facility (DWPF) at the Savannah River Site will immobilize high-level radioactive liquid waste in borosilicate glass. The glass will be poured into stainless steel canisters for eventual disposal in a geologic repository. The Department of Energy has defined a set of requirements for the DWPF canistered waste form which must be met in order to assure compatibility with, and acceptance by, the repository. These requirements are the Waste Acceptance Preliminary Specifications (WAPS). The WAPS require DWPF to report glass transition temperatures for the projected range of compositions. This information will be used by the repository to establish waste package design limits

  15. Gas microstrip detectors on polymer, silicon and glass substrates

    International Nuclear Information System (INIS)

    Barasch, E.F.; Demroff, H.P.; Drew, M.M.; Elliott, T.S.; Gaedke, R.M.; Goss, L.T.; Kasprowicz, T.B.; Lee, B.; Mazumdar, T.K.; McIntyre, P.M.; Pang, Y.; Smith, D.D.; Trost, H.J.; Vanstraelen, G.; Wahl, J.

    1993-01-01

    We present results on the performance of Gas Microstrip Detectors on various substrates. These include a 300 μm anode-anode pitch pattern on Tempax borosilicate glass and ABS/copolyether, a 200 μm pattern on Upilex ''S'' polyimide, Texin 4215, Tedlar, ion-implanted Kapton, orientation-dependent etched flat-topped silicon (''knife-edge chamber''), and iron-vanadium glass, and a 100 μm pitch pattern on Upilex ''S'' and ion-implanted Kapton. (orig.)

  16. Strategy for product composition control in the Hanford Waste Vitrification Plant

    International Nuclear Information System (INIS)

    Bryan, M.F.; Piepel, G.F.

    1996-03-01

    The Hanford Waste Vitrification Plant (HWVP) will immobilize transuranic and high-level radioactive waste in borosilicate glass. The major objective of the Process/Product Model Development (PPMD) cost account of the Pacific Northwest Laboratory HWVP Technology Development (PHTD) Project is the development of a system for guiding control of feed slurry composition (which affects glass properties) and for checking and documenting product quality. This document lays out the broad structure of HWVP's product composition control system, discusses five major algorithms and technical issues relevant to this system, and sketches the path of development and testing

  17. Strategy for product composition control in the Hanford Waste Vitrification Plant

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, M.F.; Piepel, G.F.

    1996-03-01

    The Hanford Waste Vitrification Plant (HWVP) will immobilize transuranic and high-level radioactive waste in borosilicate glass. The major objective of the Process/Product Model Development (PPMD) cost account of the Pacific Northwest Laboratory HWVP Technology Development (PHTD) Project is the development of a system for guiding control of feed slurry composition (which affects glass properties) and for checking and documenting product quality. This document lays out the broad structure of HWVP`s product composition control system, discusses five major algorithms and technical issues relevant to this system, and sketches the path of development and testing.

  18. Crystallization study of a glass used for fission product storage

    International Nuclear Information System (INIS)

    Morlevat, J.-P.; Uny, Gisele; Jacquet-Francillon, Noel.

    1981-06-01

    The vitreous matrix used in France is a borosilicate glass of low melting point allowing introduction of volatil fission products and of good chemical stability. However, like any glass, if storage temperature is higher than transformation temperature a partial crystallization can occur. Before final storage, it is important to determine of leaching by water eventually occuring on the choosen site is modified by crystalline phases. The aim of this study is the determination of the leaching rate and the identification of crystalline phases formed during thermal treatment and evaluation of its volumic fraction [fr

  19. Rapid protein immobilization for thin film continuous flow biocatalysis.

    Science.gov (United States)

    Britton, Joshua; Raston, Colin L; Weiss, Gregory A

    2016-08-09

    A versatile enzyme immobilization strategy for thin film continuous flow processing is reported. Here, non-covalent and glutaraldehyde bioconjugation are used to immobilize enzymes on the surfaces of borosilicate reactors. This approach requires only ng of protein per reactor tube, with the stock protein solution readily recycled to sequentially coat >10 reactors. Confining reagents to thin films during immobilization reduced the amount of protein, piranha-cleaning solution, and other reagents by ∼96%. Through this technique, there was no loss of catalytic activity over 10 h processing. The results reported here combines the benefits of thin film flow processing with the mild conditions of biocatalysis.

  20. Effect of Uniformly and Nonuniformly Coated Al2O3 Nanoparticles over Glass Tube Heater on Pool Boiling

    Directory of Open Access Journals (Sweden)

    Nitin Doifode

    2016-01-01

    Full Text Available Effect of uniformly and nonuniformly coated Al2O3 nanoparticles over plain glass tube heater on pool boiling heat transfer was studied experimentally. A borosilicate glass tube coated with Al2O3 nanoparticle was used as test heater. The boiling behaviour was studied by using high speed camera. Result obtained for pool boiling shows enhancement in heat transfer for nanoparticle coated surface heater and compared with plain glass tube heater. Also heat transfer coefficient for nonuniformly coated nanoparticles was studied and compared with uniformly coated and plain glass tube. Coating effect of nanoparticles over glass tube increases its surface roughness and thereby creates more nucleation sites.

  1. Étude de vitrocéramiques modèles riches en CaMoO4 pour le confinement de déchets nucléaires

    OpenAIRE

    Taurines, Tatiana

    2012-01-01

    MoO3 is poorly soluble in borosilicate glasses which can lead to the crystallization of undesired phases when its concentration or the charge load (minor actinides and fission products concentration) is too high. Crystallization control is needed to guarantee good immobilization properties. We studied powellite-rich glass-ceramics obtained from a simplified nuclear glass in the system SiO2 - B2O3 - Na2O - CaO - Al2O3 - MoO3 - RE2O3 (RE = Gd, Eu, Nd) by various heat treatments. Rare earth elem...

  2. Câmaras climáticas para o envelhecimento acelerado: ação de microambientes sobre bens culturais Environmental chambers for the accelerated ageing: effect of microclimates on cultural heritage

    Directory of Open Access Journals (Sweden)

    Renato Inhasz Paiva

    2010-01-01

    Full Text Available Environmental chambers were designed for the accelerated ageing of materials used in artistic artifacts to study the synergistic action of temperature, humidity, UV and visible radiation and gaseous pollutants. Two inox-steel/PTFE compartments are kept under controlled temperature and relative humidity, whose values are transmitted to a PC, which stores, plots in real time and continuously feedback heating and humidifying devices through logical signals. A borosilicate, or quartz, window allows the irradiation inside the chamber from an external source. A flow of purified air purges the chamber and conveys selected pollutants from an external source. Each independent compartment works under either stationary or cyclic conditions.

  3. Phase composition of yttrium-doped zirconia ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Hennig, Christoph; Scheinost, Andreas C. [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Molecular Structures; Weiss, Stephan [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes; Ikeda-Ohno, Atsushi [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Chemistry of the F-Elements; Gumeniuk, R. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Experimentelle Physik

    2017-06-01

    Ceramic material might be an alternative to borosilicate glass for the immobilization of nuclear waste. The crystallinity of ceramic material increases the corrosion resistance over several magnitudes in relation to amorphous glasses. The stability of such ceramics depend on several parameters, among them the crystal phase composition. A reliable quantitative phase analysis is necessary to correlate the macroscopic material properties with structure parameters. We performed a feasibility study based on yttrium-doped zirconia ceramics as analogue for trivalent actinides to ascertain that the nanosized crystal phases in zirconia ceramics can be reliably determined.

  4. Influence of some additions on zircon synthesis and its properties

    International Nuclear Information System (INIS)

    Goryacheva, Z.E.; Poplevina, O.G.; Suvorov, S.A.; Toropov, A.N.

    1978-01-01

    Kinetics of zircon synthesis from pure ZrO 2 and SiO 2 is studied in the presence of additions of magnesium, calcium and rare earth oxides. The addition introduction accelerates zircon formation, its yield reaching 97% at 1600 deg C. Constants of zircon formation reaction rate are determined in the presence of additions of various oxides. It is shown that synthetic zircon surpasses the natural one in tensile and density properties at similar thermostability. It is stable to the effect of molten alkaline borosilicate glass and does not polute it

  5. Optimizing light-cured composite through variations in camphorquinone and butylhydroxytoluene concentrations

    OpenAIRE

    NASSAR, Hani; CHU, Tien-Min; PLATT, Jeffrey

    2016-01-01

    Abstract The use of a free-radical polymerization inhibitor, butylhydroxytoluene (BHT), and a common photo-initiator, camphorquinone (CQ), to reduce polymerization stress in dental composite was investigated in this study. Samples were prepared by mixing Bis-GMA, UDMA, and TEGDMA at a 1:1:1 ratio (wt%), and silanized borosilicate glass fillers at 70 wt% were added to form the composite. Sixteen groups of resin composite were prepared using combinations of four CQ (0.1%, 0.5%, 1.0%, and 1.5%) ...

  6. The effect of chromium oxide on the properties of simulated nuclear waste glasses

    Energy Technology Data Exchange (ETDEWEB)

    Vojtech, O.; Sussmilch, J.; Urbanec, Z. [and others

    1996-02-01

    A study of the effect of chromium on the properties of selected glasses was performed in the frame of a Contract between Battelle, Pacific Northwest Laboratories and Nuclear Research Institute, ReZ. In the period from July 1994 to June 1995 two borosilicate glasses of special composition were prepared according to the PNL procedure and their physical and structural characteristics of glasses were studied. This Final Report contains a vast documentation on the properties of all glasses studied. For the preparation of the respective technology more detailed study of physico-chemical properties and crystallinity of investigated systems would be desirable.

  7. Preliminary evaluation of alternative forms for immobilization of Savannah River Plant high-level waste

    International Nuclear Information System (INIS)

    Stone, J.A.; Goforth, S.T. Jr.; Smith, P.K.

    1979-12-01

    An evaluation of available information on eleven alternative solid forms for immobilization of SRP high-level waste has been completed. Based on the assessment of both product and process characteristics, four forms were selected for more detailed evaluation: (1) borosilicate glass made in the reference process, (2) a high-silica glass made from a porous glass matrix, (3) crystalline ceramics such as supercalcine or SYNROC, and (4) ceramics coated with an impervious barrier. The assessment includes a discussion of product and process characteristics for each of the eleven forms, a cross comparison of these characteristics for the forms, and the bases for selecting the most promising forms for further study

  8. Formation of a glassy phase in ceramic-like coatings

    International Nuclear Information System (INIS)

    Sazonova, M.V.; Gorbatova, G.N.

    1986-01-01

    The authors investigate the synthesis directly in coatings of a borosilicate melt that could fill the role of glassy matrix, thereby avoiding fusion and processing of the glassy material. The effect of added boron on the formation of coatings based on molybdenum disilicide and tungsten disilicide in air at 900 degrees C is presented. Without an additive no coating forms; there is no adhesion to the graphite and a continuous film does not form. As a result of boron oxidation an easily fused glassy matrix forms, which bonds the molybdenum disilicide or tungsten disilicide particles together and ensures adhesion to the graphite

  9. Quarterly Progress Report Research And Development Activities Waste Fixation Program October Through December 1976

    International Nuclear Information System (INIS)

    McElroy, J. L.

    1977-01-01

    Research and development activities of the Waste Fixation Program for October through December 1976 are described in this report. The objective of this program is to develop processes to convert high-level radioactive liquid waste (HLLW) to solid forms that are demonstrated to be physically, chemically, and radiolytically stable and inert. The scope of this program encompasses plans to make available a flexible advancing technology for the solidification of radioactive waste. Early technology will produce borosilicate glass by in-can melting and continuous electric melters. Multibarrier waste forms will be developed for future application

  10. Defense Waste Processing Facility (DWPF): The vitrification of high-level nuclear waste. (Latest citations from the Bibliographic database). Published Search

    International Nuclear Information System (INIS)

    1993-09-01

    The bibliography contains citations concerning a production-scale facility and the world's largest plant for the vitrification of high-level radioactive nuclear wastes (HLW) located in the United States. Initially based on the selection of borosilicate glass as the reference waste form, the citations present the history of the development including R ampersand D projects and the actual construction of the production facility at the DOE Savannah River Plant (SRP). (Contains a minimum of 177 citations and includes a subject term index and title list.)

  11. Mechanisms and application of the Excimer laser doping from spin-on glass sources for USJ fabrication

    Science.gov (United States)

    Coutanson, S.; Fogarassy, E.; Venturini, J.

    2006-04-01

    In this work was investigated numerically and experimentally a simple laser doping method employing borosilicate (BSG) glass films as dopant sources which are deposited onto Si by the spin-coating technique. Both short (20 ns) and long (200 ns) pulse duration Excimer laser beams were used to deposit a large amount of energy in short time onto the near-surface region. Under suitable conditions, the irradiation leads to surface melting and dopant incorporation by liquid phase diffusion from the surface. Boron distribution profiles in the two-pulse duration regimes were studied as well as their electrical properties, and the junction formation of less than 25 nm in depth was demonstrated.

  12. Very High Speed Integrated Circuits - VHSIC - Final Program Repoort

    Science.gov (United States)

    1990-09-30

    mlore than 2x10 11 rads/s, while SEU testing with heavy ions under normal bias conditions produced no upsets at effective linear energy transfers up to...well implanted into a 5-7 ohm-cm, p-type epi- layer. The well used a high energy phosphorous implant driven to a depth of 2.0 microns. A nitride (Si...degraded. This prompted a study of boro-silicate glass ( BSG ) for planarization. The test runs showed a dramatic improvement in the densely populated areas

  13. Solidification of Savannah River Plant high-level waste

    International Nuclear Information System (INIS)

    Maher, R.; Shafranek, L.F.; Stevens, W.R. III.

    1983-01-01

    The Department of Energy, in accord with recommendations from the Du Pont Company, has started construction of a Defense Waste Processing Facility (DWPF) at the Savannah River Plant. The facility should be completed by the end of 1988, and full-scale operation should begin in 1990. This facility will immobilize in borosilicate glass the large quantity of high-level radioactive waste now stored at the plant plus the waste to be generated from continued chemical reprocessing operations. The existing wastes at the Savannah River Plant will be completely converted by about 2010. 21 figures

  14. Hanford Waste Vitrification Program process development: Melt testing subtask, pilot-scale ceramic melter experiment, run summary

    International Nuclear Information System (INIS)

    Nakaoka, R.K.; Bates, S.O.; Elmore, M.R.; Goles, R.W.; Perez, J.M.; Scott, P.A.; Westsik, J.H.

    1996-03-01

    Hanford Waste Vitrification Program (HWVP) activities for FY 1985 have included engineering and pilot-scale melter experiments HWVP-11/HBCM-85-1 and HWVP-12/PSCM-22. Major objectives designated by HWVP fo these tests were to evaluate the processing characteristics of the current HWVP melter feed during actual melter operation and establish the product quality of HW-39 borosilicate glass. The current melter feed, defined during FY 85, consists of reference feed (HWVP-RF) and glass-forming chemicals added as frit

  15. Hanford Waste Vitrification Plant full-scale feed preparation testing with water and process simulant slurries

    Energy Technology Data Exchange (ETDEWEB)

    Gaskill, J.R.; Larson, D.E.; Abrigo, G.P. [and others

    1996-03-01

    The Hanford Waste Vitrification Plant was intended to convert selected, pretreated defense high-level waste and transuranic waste from the Hanford Site into a borosilicate glass. A full-scale testing program was conducted with nonradioactive waste simulants to develop information for process and equipment design of the feed-preparation system. The equipment systems tested included the Slurry Receipt and Adjustment Tank, Slurry Mix Evaporator, and Melter-Feed Tank. The areas of data generation included heat transfer (boiling, heating, and cooling), slurry mixing, slurry pumping and transport, slurry sampling, and process chemistry. 13 refs., 129 figs., 68 tabs.

  16. Hanford Waste Vitrification Program process development: Melt testing subtask, pilot-scale ceramic melter experiment, run summary

    Energy Technology Data Exchange (ETDEWEB)

    Nakaoka, R.K.; Bates, S.O.; Elmore, M.R.; Goles, R.W.; Perez, J.M.; Scott, P.A.; Westsik, J.H.

    1996-03-01

    Hanford Waste Vitrification Program (HWVP) activities for FY 1985 have included engineering and pilot-scale melter experiments HWVP-11/HBCM-85-1 and HWVP-12/PSCM-22. Major objectives designated by HWVP fo these tests were to evaluate the processing characteristics of the current HWVP melter feed during actual melter operation and establish the product quality of HW-39 borosilicate glass. The current melter feed, defined during FY 85, consists of reference feed (HWVP-RF) and glass-forming chemicals added as frit.

  17. Performance of a large-scale melter off-gas system utilizing simulated SRP DWPF waste

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, J L; Randall, C T

    1984-03-01

    The Department of Energy and the DuPont Company have begun construction of a Defense Waste Processing Facility to immobilize radioactive waste now stored as liquids at the Department of Energy's Savannah River Plant. The immobilization process solidifies waste sludge by vitrification into a leach-resistant borosilicate glass. Development of the process has been the responsibility of the Savannah River Laboratory. As part of the development, two large-scale glass melter systems have been designed and operated with simulated waste. Experimental data from these operations show that process requirements will be met. 6 references, 8 figures, 4 tables.

  18. Modeling of microdevices for SAW-based acoustophoresis - A study of boundary conditions

    DEFF Research Database (Denmark)

    Skov, Nils Refstrup; Bruus, Henrik

    2016-01-01

    We present a finite-element method modeling of acoustophoretic devices consisting of a single, long, straight, water-filled microchannel surrounded by an elastic wall of either borosilicate glass (pyrex) or the elastomer polydimethylsiloxane (PDMS) and placed on top of a piezoelectric transducer...... that actuates the device by surface acoustic waves (SAW). We compare the resulting acoustic fields in these full solid-fluid models with those obtained in reduced fluid models comprising of only a water domain with simplified, approximate boundary conditions representing the surrounding solids. The reduced...

  19. Processing and properties of SiCf/SiBOC ceramic matrix composites by polyborosiloxane impregnation and pyrolysis

    Science.gov (United States)

    Vijay, Vipin; Prabhakaran, P. V.; Devasia, Renjith

    2013-06-01

    SiCf/SiBOC Ceramic Matrix Composites (CMCs) were fabricated using polyborosiloxane as the matrix resin and Nicalon™ NL-202 silicon carbide fiber as the reinforcement via polymer infiltration/impregnation and pyrolysis process (PIP). Repeated PIP cycles resulted in CMCs with a density value of ≈ 2 g/cc and a maximum average flexural strength value of 108 MPa. Oxidation resistance of SiCf/SiBOC was compared with Cf/C and Cf/SiBOC at 1000°C. SiCf/SiBOC composite shows a better oxidation resistance due to the formation of a protective layer of amorphous borosilicate glass on oxidation.

  20. Modeling the Deformation-Failure Mechanisms of Thin Hollow Glass Microspheres

    Science.gov (United States)

    Garza-Cruz, Tryana V.; Nakagawa, Masami

    2009-06-01

    Thin Hollow Glass Microspheres (HGMs) are a potential candidate to insulate cryogenic tanks due to their high strength-to-weight ratio and thermal properties. In this study, HGMs were modeled using a Discrete Element Method (DEM) to simulate their deformation and fracture behavior. Due to lack of actual data, a chemical composition-based methodology was introduced to synthesize material properties that reproduce the mechanical properties of soda-lime-borosilicate glass. The modeled microsphere was subjected to a uniaxial compression test and failed due to buckling. This model captures some essential aspect of deformation-failure characteristics of a thin hollow glass microsphere.

  1. Waste removal sequencing using ProdMod

    International Nuclear Information System (INIS)

    Paul, P.K.; Gregory, M.V.; Davis, N.R.; Brooke, J.N.

    1996-01-01

    The Savannah River Site (SRS) is starting to solidify its accumulated high-level radioactive waste into borosilicate glass in stainless steel canisters for eventual permanent storage. The in-tank precipitation process (ITP) and extended sludge processing (ESP) are two key operations in the waste processing complex. The supernate and dissolved salt from the waste storage tanks are transferred to the ITP process tank where the solution is decontaminated in batch processes. Soluble radioactive cesium is precipitated with sodium tetraphenylborate and strontium, uranium, and plutonium are adsorbed on monosodium titanate. The precipitate and adsorbent solids, which now contain the radionuclides, are concentrated using crossflow filters. The concentrated solids are sent to the high-level waste vitrification process. The decontaminated salt solution is sent to the low-level waste solidification process to form cement grout. In parallel with the precipitate operations, insoluble sludges that settled originally to the bottom of the waste tanks are reslurried and sent to ESP to undergo washing to reduce soluble salt content and aluminum dissolution, if required. In the vitrification process in the Defense Waste Processing Facility (DWPF), the concentrated precipitate from the ITP is mixed with the washed sludge from ESP and glass frit in proportion to form a stable borosilicate glass. A novel and fast-running Production Planning Model (ProdMod) has been developed to simulate the waste processing operation. This paper describes the application of ProdMod in sequencing the ITP batches and scheduling the ESP batches

  2. Evaluation of Photocatalytic Active Coatings on Sintered Glass Tubes by Methylene Blue

    Directory of Open Access Journals (Sweden)

    Colin Awungacha Lekelefac

    2013-01-01

    Full Text Available A comparative study between ten different photocatalytic active coatings was done. The effectiveness and photocatalytic activity of the coatings were studied by degradation experiments of methylene blue (MB dye under UV light illumination. The reactor design consisting of sintered glass packed in a borosilicate tube placed between two planar dielectric barrier discharge lamps (Osram Planon is reported for the first time. The coatings consisted of either titania, silica, or zinc on sintered borosilicate glass. The advantage of sol-gel in catalyst preparation was exploited to combine catalyst to act as cocatalyst. TiO2-P25 widely applied in suspension systems was effectively immobilized on sintered glass support with the aid of tetraethylorthosilicate (TEOS solution which acted as support material. Results indicated that TiO2-P25+SiO2, TiO2-P25+SiO2+Pt, and TiOSO4_30,6wt% films showed highest degradation rates close to 100% after 90 min illumination with degradation rates exceeding 50% after 30 minutes. TTIP+Pt showed lowest degradation rate.

  3. Development of graded Ni-YSZ composite coating on Alloy 690 by Pulsed Laser Deposition technique to reduce hazardous metallic nuclear waste inventory.

    Science.gov (United States)

    Sengupta, Pranesh; Rogalla, Detlef; Becker, Hans Werner; Dey, Gautam Kumar; Chakraborty, Sumit

    2011-08-15

    Alloy 690 based 'nuclear waste vitrification furnace' components degrade prematurely due to molten glass-alloy interactions at high temperatures and thereby increase the volume of metallic nuclear waste. In order to reduce the waste inventory, compositionally graded Ni-YSZ (Y(2)O(3) stabilized ZrO(2)) composite coating has been developed on Alloy 690 using Pulsed Laser Deposition technique. Five different thin-films starting with Ni80YSZ20 (Ni 80 wt%+YSZ 20 wt%), through Ni60YSZ40 (Ni 60 wt%+YSZ 40 wt%), Ni40YSZ60 (Ni 40 wt%+YSZ 60 wt%), Ni20YSZ80 (Ni 20 wt%+YSZ 80 wt%) and Ni0YSZ100 (Ni 0 wt%+YSZ 100 wt%), were deposited successively on Alloy 690 coupons. Detailed analyses of the thin-films identify them as homogeneous, uniform, pore free and crystalline in nature. A comparative study of coated and uncoated Alloy 690 coupons, exposed to sodium borosilicate melt at 1000°C for 1-6h suggests that the graded composite coating could substantially reduced the chemical interactions between Alloy 690 and borosilicate melt. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Lead iron phosphate glass as a containment medium for disposal of high-level nuclear waste

    Science.gov (United States)

    Boatner, Lynn A.; Sales, Brian C.

    1989-01-01

    Lead-iron phosphate glasses containing a high level of Fe.sub.2 O.sub.3 for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a highly corrosion resistant, homogeneous, easily processed glass can be formed. For corroding solutions at 90.degree. C., with solution pH values in the range between 5 and 9, the corrosion rate of the lead-iron phosphate nuclear waste glass is at least 10.sup.2 to 10.sup.3 times lower than the corrosion rate of a comparable borosilicate nuclear waste glass. The presence of Fe.sub.2 O.sub.3 in forming the lead-iron phosphate glass is critical. Lead-iron phosphate nuclear waste glass can be prepared at temperatures as low as 800.degree. C., since they exhibit very low melt viscosities in the 800.degree. to 1050.degree. C. temperature range. These waste-loaded glasses do not readily devitrify at temperatures as high as 550.degree. C. and are not adversely affected by large doses of gamma radiation in H.sub.2 O at 135.degree. C. The lead-iron phosphate waste glasses can be prepared with minimal modification of the technology developed for processing borosilicate glass nuclear wasteforms.

  5. Modelling the local atomic structure of molybdenum in nuclear waste glasses with ab initio molecular dynamics simulations.

    Science.gov (United States)

    Konstantinou, Konstantinos; Sushko, Peter V; Duffy, Dorothy M

    2016-09-21

    The nature of chemical bonding of molybdenum in high level nuclear waste glasses has been elucidated by ab initio molecular dynamics simulations. Two compositions, (SiO 2 ) 57.5 -(B 2 O 3 ) 10 -(Na 2 O) 15 -(CaO) 15 -(MoO 3 ) 2.5 and (SiO 2 ) 57.3 -(B 2 O 3 ) 20 -(Na 2 O) 6.8 -(Li 2 O) 13.4 -(MoO 3 ) 2.5 , were considered in order to investigate the effect of ionic and covalent components on the glass structure and the formation of the crystallisation precursors (Na 2 MoO 4 and CaMoO 4 ). The coordination environments of Mo cations and the corresponding bond lengths calculated from our model are in excellent agreement with experimental observations. The analysis of the first coordination shell reveals two different types of molybdenum host matrix bonds in the lithium sodium borosilicate glass. Based on the structural data and the bond valence model, we demonstrate that the Mo cation can be found in a redox state and the molybdate tetrahedron can be connected with the borosilicate network in a way that inhibits the formation of crystalline molybdates. These results significantly extend our understanding of bonding in Mo-containing nuclear waste glasses and demonstrate that tailoring the glass composition to specific heavy metal constituents can facilitate incorporation of heavy metals at high concentrations.

  6. Destruction of carbon tetrachloride in a dielectric barrier/packed-bed corona reactor

    Science.gov (United States)

    Tonkyn, R. G.; Barlow, S. E.; Orlando, T. M.

    1996-11-01

    The destruction of low concentrations (corona reactor was studied. We compare, in particular, the destruction efficiencies using either borosilicate or zirconia oxide (ZrO2) packing materials in dry and moist air, and nitrogen buffer gases. Measurements of contaminant removal in the effluent gas were made at atmospheric pressure as a function of energy dissipated in the reactor. In dry N2, destruction of CCl4 was most efficient using ZrO2 beads, whereas, in dry air, contaminant removal was approximately equal for borosilicate glass and ZrO2. The presence of water in the gas stream reduced the CCl4 destruction efficiency under all conditions. This reduction was likely a synergistic effect that involves changes in the plasma density, scavenging of low energy secondary electrons, and possible surface passivation. Assuming the primary step in CCl4 destruction is dissociative electron attachment, an estimate of the average density of low energy electrons as a function of input energy was made. We relate the enhancement in CCl4 destruction using the ZrO2 beads in N2 to a slight increase in the number density of low energy secondary electrons. A discussion of the importance of energy density measurements and a useful phenomenological kinetic model consistent with the observed results are presented.

  7. Vitrification of high-level liquid wastes

    International Nuclear Information System (INIS)

    Varani, J.L.; Petraitis, E.J.; Vazquez, Antonio.

    1987-01-01

    High-level radioactive liquid wastes produced in the fuel elements reprocessing require, for their disposal, a preliminary treatment by which, through a series of engineering barriers, the dispersion into the biosphere is delayed by 10 000 years. Four groups of compounds are distinguished among a great variety of final products and methods of elaboration. From these, the borosilicate glasses were chosen. Vitrification experiences were made at a laboratory scale with simulated radioactive wastes, employing different compositions of borosilicate glass. The installations are described. A series of tests were carried out on four basic formulae using always the same methodology, consisting of a dry mixture of the vitreous matrix's products and a dry simulated mixture. Several quality tests of the glasses were made 1: Behaviour in leaching following the DIN 12 111 standard; 2: Mechanical resistance; parameters related with the facility of the different glasses for increasing their surface were studied; 3: Degree of devitrification: it is shown that devitrification turns the glasses containing radioactive wastes easily leachable. From all the glasses tested, the composition SiO 2 , Al 2 O 3 , B 2 O 3 , Na 2 O, CaO shows the best retention characteristics. (M.E.L.) [es

  8. Specialty glass development for radiation shielding windows and nuclear waste immobilization

    International Nuclear Information System (INIS)

    Mandal, S.; Ghorui, S.; Roy Chowdhury, A.; Sen, R.; Chakraborty, A.K.; Sen, S.; Maiti, H.S.

    2015-01-01

    The technology of two important varieties of specialty glasses, namely high density Radiation Shielding Window (RSW) glass and specialty glass beads of borosilicate composition have been successfully developed in CGCRI with an aim to meet the countries requirement. Radiation Shielding Windows used in nuclear installations, are viewing devices, which allow direct viewing into radioactive areas while still providing adequate protection to the operating personnel. The glass blocks are stabilized against damage from radiation by introducing cerium in definite proportions. Considering the essentially of developing an indigenous technology to make the country self-sufficient for this critical item, CGCRI has taken up a major programme to develop high lead containing glasses required for RSWs under a MoD with BARC. On the other hand, the specialty glass bead of specific composition and properties is a critical material required for management of radioactive waste in a closed nuclear fuel cycle that is followed by India. During reprocessing of the spent nuclear fuel, high level radio-active liquid waste (HLW) is produced containing unwanted radio isotopes some of which remain radioactive for thousands of years. The need is to immobilize them within a molecular structure so that they will not come out and be released to the ambience and thereby needs to be resolved if nuclear power is to make a significant contribution to the country's power requirement. Borosilicate glass has emerged as the material of choice for immobilization due to its unique random network structure

  9. Interfacial bonding and friction in silicon carbide (filament)-reinforced ceramic- and glass-matrix composites

    International Nuclear Information System (INIS)

    Bright, J.D.; Shetty, D.K.

    1989-01-01

    This paper reports interfacial shear strength and interfacial sliding friction stress assessed in unidirectional SiC-filament-reinforced reaction-bonded silicon nitride (RBSN) and borosilicate glass composites and 0/90 cross-ply reinforced borosilicate glass composite using a fiber pushout test technique. The interface debonding load and the maximum sliding friction load were measured for varying lengths of the embedded fibers by continuously monitoring the load during debonding and pushout of single fibers in finite-thickness specimens. The dependences of the debonding load and the maximum sliding friction load on the initial embedded lengths of the fibers were in agreement with nonlinear shear-lag models. An iterative regression procedure was used to evaluate the interfacial properties, shear debond strength (τ d ), and sliding friction stress (τ f ), from the embedded fiber length dependences of the debonding load and the maximum frictional sliding load, respectively. The shear-lag model and the analysis of sliding friction permit explicit evaluation of a coefficient of sliding friction (μ) and a residual compressive stress on the interface (σ 0 ). The cross-ply composite showed a significantly higher coefficient of interfacial friction as compared to the unidirectional composites

  10. Evolution of mechanical properties of silicate glasses: Impact of the chemical composition and effects of irradiation

    International Nuclear Information System (INIS)

    Barlet, Marina

    2014-01-01

    This thesis examines: (1) how the chemical composition changes the hardness, toughness, and stress corrosion cracking behavior in model pristine and (2) how external irradiation impact these properties. It is to be incorporated in the context of the storage of nuclear waste in borosilicate glass matrix, the structural integrity of which should be assessed. Eight simplified borosilicate glasses made of 3 oxides with modulated proportions (SiO 2 -B 2 O 3 -Na 2 O (SBN) have been selected and their hardness, toughness, and stress corrosion cracking behavior have been characterized prior and after irradiation. The comparative study of the non-irradiated SBN glasses provides the role played by the chemical composition. The sodium content is found to be the key parameter: As it increases, the glass plasticity increases, leading to changes in the mechanical response to strain. Hardness (Hv) and toughness (Kc) decrease since the flow under indenter increases. The analysis of the stress corrosion behavior evidences a clear shift of the SCC curves linked also to the glass plasticity. Four of the 8 simplified SBN glass systems highlight the influence of electron, light and heavy ions irradiations on the mechanical properties. Once again, the sodium content is a key parameter. It is found to inhibit the glass modification: Glasses with high sodium content are more stable. Ions irradiations highlight the predominant role of nuclear interaction in changing the glass properties. Finally, electronic interaction induced by helium and electron irradiation does not lead to the same structural/mechanical glasses variations. (author) [fr

  11. Annihilation of the triplet excitons in the nanoporous glass matrices

    International Nuclear Information System (INIS)

    Afanasyev, D.A.; Ibrayev, N.Kh.; Saletsky, A.M.; Starokurov, Y.V.; Gun'ko, V.M.; Mikhalovsky, S.V.

    2013-01-01

    The spectra and kinetics of fluorescence decay of 1,2-benzanthracene (1,2-BA) molecular clusters adsorbed in nanoporous borosilicate glasses were investigated. It has been shown that the type of the decay kinetics of delayed fluorescence is determined by the annihilation of triplet excitons in crystalline and percolation clusters. The influence of an external magnetic field on the annihilation rate constant of triplet excitons in the adsorbed 1,2-BA molecules has been studied. The response of the molecular clusters to the magnetic field strongly depends on temperature, pore size and time scale of the observation. Clusters with the crystal structure dominate in the decay kinetics of triplet–triplet annihilation (TTA) and delayed fluorescence in the initial microsecond period of time after excitation. Amorphous clusters determine the form of decay kinetics of delayed fluorescence in the millisecond range. The increase in the pore size and concentration of the adsorbate lead to the dominance of crystalline components. The results presented here can be used to develop techniques for probing the structure of the adsorbed layer in nanoporous systems examining the effect of an external magnetic field on the annihilation delayed fluorescence (ADF) kinetics. Highlights: ► Molecular clusters of 1,2-benzanthracene adsorbed in nanoporous borosilicate glasses. ► Form of decay kinetics of delayed fluorescence. ► Magnetic field effects depend on temperature, pore size and observation time range. ► Clusters with crystal structure and amorphous clusters form in porous glasses

  12. Velocity Gradient Maps Directly Measured by PLF

    Science.gov (United States)

    Quintella, Cristina M.; Gonçalves, Cristiane C.; Lima, Angelo Mv; Pepe, Iuri M.

    2000-11-01

    Flows are macroscopically classified as laminar or turbulent due to their velocity distributions, nevertheless most chemical and biological phenomena are yield or enhanced by intermolecular orientation and microscopic turbulence. Here was studied a 100micra liquid sheet produced by a slit nozzle, both flowing freely into air and over a borosilicate surface (roughness bellow 5nm), ranging from 17 to 36Re (143 to 297cm/s, similar to muscles and brain blood flow). Mono ethylene glycol was used either pure, or with sodium alkyl benzene sulfated (ABS) surfactant (24.5mol/L, submicellar), or with poly(ethylene oxide) (PEO) (1409ppm, 4millions aw). Velocity gradients were directly measured by 514nm polarized laser induced fluorescence (PLF) with R6G as probe. Intermolecular alignment (IA) maps were obtained all over the flow (about 1,950 points, 0.02mm2 precision). The free jet average IA has increased 57% when flowing over borosilicate. With ABS, the IA increased, suggesting wall drag reduction. With PEO the IA decreases due to solvent intermolecular forces attenuation, generating wider turbulent areas. PLF proved to be an excellent method to evaluate IA within liquid thin flows. Chosen solute additions permits IA control over wide regions.

  13. Photolysis of oxyfluorfen in aqueous methanol.

    Science.gov (United States)

    Chakraborty, Subhasish K; Chakraborty, Savitri; Bhattacharyya, Anjan; Chowdhury, Ashim

    2013-01-01

    Photolysis of oxyfluorfen, an herbicide of the nitrodiphenyl ether class, was studied in aqueous methanol under UV and sunlight. UV irradiation was carried out in a borosilicate glass photoreactor (containing 250 ppm oxyfluorfen in 50% aqueous methanol) equipped with a quartz filter and 125 watt mercury lamp (maximum output 254 nm) at 25 ± 1°C. Sunlight irradiation was conducted at 28 ± 1°C in borosilicate Erlenmeyer flasks containing 250 ppm oxyfluorfen in 50% aqueous methanol. The samples from both the irradiated conditions were withdrawn at a definite time interval and extracted to measure oxyfluorfen content by gas chromatography-flame ionization detector for rate study. The half-life values were 20 hours and 2.7 days under UV and sunlight exposure, respectively. Photolysis of oxyfluorfen yielded 13 photoproducts of which three were characterized by infrared spectrophotometer and (1)H NMR and (13)C NMR spectroscopy. The rest of the photoproducts were identified by gas chromatography-mass spectrometry (GC-MS) and thin layer chromatography (TLC). An ionization potential 70 eV was used for electron impact-mass spectrometry (EI-MS) and methane was used as reagent gas for chemical ionization-mass spectrometry (CI-MS). Two of the photoproducts were also synthesized for comparison. The main phototransformation pathways of oxyfluorfen involved nitro reduction, dechlorination, and hydrolysis as well as nucleophiles displacement reaction.

  14. Preliminary technical data summary for the Defense Waste Processing Facility, Stage 1

    International Nuclear Information System (INIS)

    1980-09-01

    This Preliminary Technical Data Summary presents the technical basis for design of Stage 1 of the Staged Defense Waste Processing Facility (DWPF), a process to efficiently immobilize the radionuclides in Savannah River Plant (SRP) high-level liquid waste. The radionuclides in SRP waste are present in sludge that has settled to the bottom of waste storage tanks and in crystallized salt and salt solution (supernate). Stage 1 of the DWPF receives washed, aluminum dissolved sludge from the waste tank farms and immobilizes it in a borosilicate glass matrix. The supernate is retained in the waste tank farms until completion of Stage 2 of the DWPF at which time it filtered and decontaminated by ion exchange in the Stage 2 facility. The decontaminated supernate is concentrated by evaporation and mixed with cement for burial. The radioactivity removed from the supernate is fixed in borosilicate glass along with the sludge. This document gives flowsheets, material, and curie balances, material and curie balance bases, and other technical data for design of the Stage 1 DWPF

  15. Development and radiation stability of glasses for highly radioactive wastes

    International Nuclear Information System (INIS)

    Hall, A.R.; Dalton, J.T.; Hudson, B.; Marples, J.A.C.

    1976-01-01

    The variation of formation temperature, crystallizing behaviour and leach resistance with composition changes for sodium-lithium borosilicate glasses suitable for vitrifying Magnox waste are discussed. Viscosities have been measured between 400 and 1050 0 C. The principal crystal phases which occur have been identified as magnesium silicate, magnesium borate and ceria. The leach rate of polished discs in pure water at 100 0 C does not decrease with time if account is taken of the fragile siliceous layer that is observed to occur. The effect of 100 years' equivalent α- and β-irradiation on glass properties is discussed. Stored energy release experiments demonstrated that energy is released over a wide temperature range so that it cannot be triggered catastrophically. Temperatures required to release energy are dependent upon the original storage temperature. Helium release is by Fick's diffusion law up to at least 30% of the total inventory, with diffusion coefficients similar to those for comparable borosilicate glasses. Leach rates were not measurably affected by α-radiation. β-radiation in a Van de Graaff accelerator did not change physical properties, but irradiation in an electron microscope caused minute bubbles in lithium-containing glasses above 200 0 C. (author)

  16. Electrical-conductivity measurements of leachates for the rapid assessment of wasteform corrosion resistance

    International Nuclear Information System (INIS)

    Sales, B.C.; Petek, M.; Boatner, L.A.

    1982-01-01

    Measurements of the electrical conductivity of leachate solutions as a function of time can be used as an efficient, informative means of evaluation and comparison in the development of nuclear waste forms and in the preliminary analysis of their corrosion resistance in distilled water. Three separate applications of this technique are described in this work. These are: (1) its use in the optimization of the corrosion resistance of a crystalline wasteform (monazite); (2) a study of the protective ability of the surface layer (gel layer) which forms on the nuclear waste glass Frit 21 + 20 wt % SRW in distilled water; and (3) making comparisons of the overall corrosion resistance of three different nuclear wasteforms (i.e., monazite, SYNROC, and borosilicate glass). A complete solution analysis of the borosilicate glass leachate and a straightforward analysis of the conductivity results agree to within +-20%. In the absence of a complete, time consuming solution analysis, conductivity measurements can be used to estimate reliably the total ionic concentration in the leachate to within a factor of 2

  17. ADDITIVE TESTING FOR IMPROVED SULFUR RETENTION: PRELIMINARY REPORT

    Energy Technology Data Exchange (ETDEWEB)

    Amoroso, J.; Fox, K.

    2011-09-07

    The Savannah River National Laboratory is collaborating with Alfred University to evaluate the potential for additives in borosilicate glass to improve sulfur retention. This preliminary report provides further background on the incorporation of sulfur in glass and outlines the experiments that are being performed by the collaborators. A simulated waste glass composition has been selected for the experimental studies. The first phase of experimental work will evaluate the impacts of BaO, PbO, and V{sub 2}O{sub 5} at concentrations of 1.0, 2.0, and 5.0 wt % on sulfate retention in simulated high level waste borosilicate glass. The second phase of experimental work will evaluate the effects of time at the melt temperature on sulfur retention. The resulting samples will be characterized to determine the amount of sulfur remaining as well as to identify the formation of any crystalline phases. The results will be used to guide the future selection of frits and glass forming chemicals in vitrifying Department of Energy wastes containing high sulfur concentrations.

  18. Performance assessment of the direct disposal in unsaturated tuff or spent nuclear fuel and high-level waste owned by USDOE: Volume 2, Methodology and results

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P. [ed.

    1995-03-01

    This assessment studied the performance of high-level radioactive waste and spent nuclear fuel in a hypothetical repository in unsaturated tuff. The results of this 10-month study are intended to help guide the Office of Environment Management of the US Department of Energy (DOE) on how to prepare its wastes for eventual permanent disposal. The waste forms comprised spent fuel and high-level waste currently stored at the Idaho National Engineering Laboratory (INEL) and the Hanford reservations. About 700 metric tons heavy metal (MTHM) of the waste under study is stored at INEL, including graphite spent nuclear fuel, highly enriched uranium spent fuel, low enriched uranium spent fuel, and calcined high-level waste. About 2100 MTHM of weapons production fuel, currently stored on the Hanford reservation, was also included. The behavior of the waste was analyzed by waste form and also as a group of waste forms in the hypothetical tuff repository. When the waste forms were studied together, the repository was assumed also to contain about 9200 MTHM high-level waste in borosilicate glass from three DOE sites. The addition of the borosilicate glass, which has already been proposed as a final waste form, brought the total to about 12,000 MTHM.

  19. Characterization of the Defense Waste Processing Facility (DWPF) Environmental Assessment (EA) glass standard reference material

    International Nuclear Information System (INIS)

    Jantzen, C.M.; Bibler, N.E.; Beam, D.C.

    1992-01-01

    Liquid high-level nuclear waste at the Savannah River Site (SRS) will be immobilized by vitrification in borosilicate glass. The glass will be produced and poured into stainless steel canisters in the Defense Waste Processing Facility (DWPF). Other waste form producers, such as West Valley Nuclear Services (WVNS) and the Hanford Waste Vitrification Project (HWVP), will also immobilize high-level radioactive waste in borosilicate glass. The canistered waste will be stored temporarily at each facility for eventual permanent disposal in a geologic repository. The Department of Energy has defined a set of requirements for the canistered waste forms, the Waste Acceptance Preliminary Specifications (WAPS). The current Waste Acceptance Preliminary Specification (WAPS) 1.3, the product consistency specification, requires the waste form producers to demonstrate control of the consistency of the final waste form using a crushed glass durability test, the Product Consistency Test (PCT). In order to be acceptable, a waste glass must be more durable during PCT analysis than the waste glass identified in the DWPF Envirorunental Assessment (EA). In order to supply all the waste form producers with the same standard benchmark glass, 1000 pounds of the EA glass was fabricated. The chemical analyses and characterization of the benchmark EA glass are reported. This material is now available to act as a durability, analytic, and/or redox Standard Reference Material (SRM) for all waste form producers

  20. Performance assessment of the direct disposal in unsaturated tuff or spent nuclear fuel and high-level waste owned by USDOE: Volume 2, Methodology and results

    International Nuclear Information System (INIS)

    Rechard, R.P.

    1995-03-01

    This assessment studied the performance of high-level radioactive waste and spent nuclear fuel in a hypothetical repository in unsaturated tuff. The results of this 10-month study are intended to help guide the Office of Environment Management of the US Department of Energy (DOE) on how to prepare its wastes for eventual permanent disposal. The waste forms comprised spent fuel and high-level waste currently stored at the Idaho National Engineering Laboratory (INEL) and the Hanford reservations. About 700 metric tons heavy metal (MTHM) of the waste under study is stored at INEL, including graphite spent nuclear fuel, highly enriched uranium spent fuel, low enriched uranium spent fuel, and calcined high-level waste. About 2100 MTHM of weapons production fuel, currently stored on the Hanford reservation, was also included. The behavior of the waste was analyzed by waste form and also as a group of waste forms in the hypothetical tuff repository. When the waste forms were studied together, the repository was assumed also to contain about 9200 MTHM high-level waste in borosilicate glass from three DOE sites. The addition of the borosilicate glass, which has already been proposed as a final waste form, brought the total to about 12,000 MTHM

  1. Corrosion Testing of Monofrax K-3 Refractory in Defense Waste Processing Facility (DWPF) Alternate Reductant Feeds

    Energy Technology Data Exchange (ETDEWEB)

    Williams, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Jantzen, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-04-06

    The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) uses a combination of reductants and oxidants while converting high level waste (HLW) to a borosilicate waste form. A reducing flowsheet is maintained to retain radionuclides in their reduced oxidation states which promotes their incorporation into borosilicate glass. For the last 20 years of processing, the DWPF has used formic acid as the main reductant and nitric acid as the main oxidant. During reaction in the Chemical Process Cell (CPC), formate and formic acid release measurably significant H2 gas which requires monitoring of certain vessel’s vapor spaces. A switch to a nitric acid-glycolic acid (NG) flowsheet from the nitric-formic (NF) flowsheet is desired as the NG flowsheet releases considerably less H2 gas upon decomposition. This would greatly simplify DWPF processing from a safety standpoint as close monitoring of the H2 gas concentration could become less critical. In terms of the waste glass melter vapor space flammability, the switch from the NF flowsheet to the NG flowsheet showed a reduction of H2 gas production from the vitrification process as well. Due to the positive impact of the switch to glycolic acid determined on the flammability issues, evaluation of the other impacts of glycolic acid on the facility must be examined.

  2. Simulation of Self-Irradiation of High-Sodium Content Nuclear Waste Glasses

    International Nuclear Information System (INIS)

    Pankov, Alexey S.; Ojovan, Michael I.; Batyukhnova, Olga G.; Lee, William E.

    2007-01-01

    Alkali-borosilicate glasses are widely used in nuclear industry as a matrix for immobilisation of hazardous radioactive wastes. Durability or corrosion resistance of these glasses is one of key parameters in waste storage and disposal safety. It is influenced by many factors such as composition of glass and surrounding media, temperature, time and so on. As these glasses contain radioactive elements most of their properties including corrosion resistance are also impacted by self-irradiation. The effect of external gamma-irradiation on the short-term (up to 27 days) dissolution of waste borosilicate glasses at moderate temperatures (30 deg. to 60 deg. C) was studied. The glasses studied were Magnox Waste glass used for immobilisation of HLW in UK, and K-26 glass used in Russia for ILW immobilisation. Glass samples were irradiated under γ-source (Co-60) up to doses 1 and 11 MGy. Normalised rates of elemental release and activation energy of release were measured for Na, Li, Ca, Mg, B, Si and Mo before and after irradiation. Irradiation up to 1 MGy results in increase of leaching rate of almost all elements from both MW and K-26 with the exception of Na release from MW glass. Further irradiation up to a dose of 11 MGy leads to the decrease of elemental release rates to nearly initial value. Another effect of irradiation is increase of activation energies of elemental release. (authors)

  3. Management of cesium loaded AMP- Part I preparation of 137Cesium concentrate and cementation of secondary wastes

    International Nuclear Information System (INIS)

    Singh, I.J.; Sathi Sasidharan, N.; Yalmali, Vrunda S.; Deshingkar, D.S.; Wattal, P.K.

    2005-11-01

    Separation of 137 cesium from High Level Waste can be achieved by use of composite-AMP, an engineered form of Ammonium Molybdo-Phosphate(AMP). Direct vitrification of cesium loaded composite AMP in borosilicate glass matrix leads to separation of water soluble molybdate phase. A proposed process describes two different routes of selective separation of molybdates and phosphate to obtain solutions of cesium concentrates. Elution of 137 Cesium from composite-AMP by decomposing it under flow conditions using saturated barium hydroxide was investigated. This method leaves molybdate and phosphate embedded in the column but only 70% of total cesium loaded on column could be eluted. Alternatively composite-AMP was dissolved in sodium hydroxide and precipitation of barium molybdate-phosphate from the resultant solution, using barium nitrate was investigated by batch methods. The precipitation technique gave over 99.9% of 137 Cesium activity in solutions, free of molybdates and phosphates, which is ideally suited for immobilization in borosilicate glass matrix. Detailed studies were carried out to immobilize secondary waste of 137 Cesium contaminated barium molybdate-phosphate precipitates in the slag cement matrix using vermiculite and bentonite as admixtures. The cumulative fraction of 137 Cs leached from the cement matrix blocks was 0.05 in 140 days while the 137 Cs leach rate was 0.001 gm/cm 2 /d. (author)

  4. Epsilon metal waste form for immobilization of noble metals from used nuclear fuel

    Science.gov (United States)

    Crum, Jarrod V.; Strachan, Denis; Rohatgi, Aashish; Zumhoff, Mac

    2013-10-01

    Epsilon metal (ɛ-metal), an alloy of Mo, Pd, Rh, Ru, and Tc, is being developed as a waste form to treat and immobilize the undissolved solids and dissolved noble metals from aqueous reprocessing of commercial used nuclear fuel. Epsilon metal is an attractive waste form for several reasons: increased durability relative to borosilicate glass, it can be fabricated without additives (100% waste loading), and in addition it also benefits borosilicate glass waste loading by eliminating noble metals from the glass, thus the processing problems related to their insolubility in glass. This work focused on the processing aspects of the epsilon metal waste form development. Epsilon metal is comprised of refractory metals resulting in high alloying temperatures, expected to be 1500-2000 °C, making it a non-trivial phase to fabricate by traditional methods. Three commercially available advanced technologies were identified: spark-plasma sintering, microwave sintering, and hot isostatic pressing, and investigated as potential methods to fabricate this waste form. Results of these investigations are reported and compared in terms of bulk density, phase assemblage (X-ray diffraction and elemental analysis), and microstructure (scanning electron microscopy).

  5. Operation of microstrip gas chambers manufactured on glass coated with high resistivity diamond-like layers

    CERN Document Server

    Boimska, B; Dominik, Wojciech; Hoch, M; Million, Gilbert; Ropelewski, Leszek; Sauli, Fabio; Sharma, A

    1997-01-01

    We describe recent observations and measurements realized with micro-strip gas chambers (MSGCs) manufactured on boro-silicate glass coated with a thin layer of diamond-like carbon (DLC) having a surface resistivity around 4.10$^{16}\\Omega/\\Box$. The role of the back-pla electrode configuration and potential in the detector performance has been studied. Even for this very high resistivity of the coatings, MSGCs operate differently from those manufactured on bare boro-silicate glass; the charge gain increases with the radiation flux for counting rates above 103 Hz/mm2, reaching a value 60% higher for 105 Hz/mm2. This behavior does not depend on the presence and potential of the back plane electrode; however, both maximum gain and rate capability are influenced by the drift field. From this study, compared with measurements realized previously with other detectors, we deduce that for stable high rate operation of MSGCs the resistivity of the coating should not exceed ~10$^{15}\\Omega/\\Box$.

  6. Radiation effects in glass and glass-ceramic waste forms for the immobilization of CANDU UO2 fuel reprocessing waste

    International Nuclear Information System (INIS)

    Tait, J.C.

    1993-05-01

    AECL has investigated three waste forms for the immobilization of high-level liquid wastes that would arise if used CANDU fuels were reprocessed at some time in the future to remove fissile materials for the fabrication of new power reactor fuel. These waste forms are borosilicate glasses, aluminosilicate glasses and titanosilicate glass-ceramics. This report discusses the potential effects of alpha, beta and gamma radiation on the releases of radionuclides from these waste forms as a result of aqueous corrosion by groundwaters that would be present in an underground waste disposal vault. The report discusses solid-state damage caused by radiation-induced atomic displacements in the waste forms as well as irradiation of groundwater solutions (radiolysis), and their potential effects on waste-form corrosion and radionuclide release. The current literature on radiation effects on borosilicate glasses and in ceramics is briefly reviewed, as are potential radiation effects on specialized waste forms for the immobilization of 129 I, 85 Kr and 14 C. (author). 104 refs., 9 tabs., 5 figs

  7. Crystallite size and film-substrate interface mediated structural evolution of silicon thin films

    Science.gov (United States)

    Mohiddon, Md. Ahamad; Krishna, M. Ghanashyam

    2013-09-01

    The effect of crystallite size and the film-substrate interface on the crystal structure of Si nanoparticles leading to the stabilization of wurtzite structure in Si films is reported. Bilayers of Ni(50 nm)/Si(400 nm) were deposited on fused silica (FS) and borosilicate glass (BSG) substrates by electron beam evaporation. The as deposited films, which were amorphous, crystallized at a post deposition annealing temperature of 400 °C on BSG and 500 °C on FS substrates. Electron diffraction studies showed that the nanocrystalline Si on BSG crystallized into the wurtzite structure with a crystallite size of 45 nm. In contrast, the nanocrystals of Si on FS crystallized in the diamond cubic structure with a crystallite size of 220 nm. The presence of the wurtzite phase is confirmed by the Raman line at 504 cm-1, whereas the signature of the cubic phase appears at 520 cm-1. The composites with Si in the wurtzite structure exhibit higher refractive index of 2.10 (at 1000 nm) than the films with Si in the diamond cubic structure 1.95 (at 1000 nm). The optical band gap in both cases is 2.1 eV. The stabilization of the wurtzite phase is attributed to the lower crystallite size of Si on the borosilicate glass substrate.

  8. Adsorption of polypropylene oxide-polyethylene oxide type surfactants at surfaces of pharmaceutical relevant materials: effect of surface energetics and surfactant structures.

    Science.gov (United States)

    Li, Jinjiang; Rudraraju, Sneha; Zheng, Songyan; Jaiswal, Archana

    2018-01-18

    Protein therapeutics are exposed to various surfaces during product development, where their adsorption possibly causes unfolding, denaturation, and aggregation. In this paper, we aim to characterize four types of typical surfaces used in the development of biologics: polycarbonate, polyethersulfone, borosilicate glass, and cellulose. Contact angles of these surfaces were measured using three probing liquids: water, formamide, and diidomethane, from which acid/base (AB) and Lifshitz-van der Waals (LW) interaction components were derived. To explore the interactions of surfactants of Pluronics/Poloxamers (PEO-PPO-PEO copolymers) with these surfaces, the adsorption of three Pluronics (F68, F127, and L44) at these surfaces was determined using a quartz crystal microbalance with dissipation technique (QCM-D). For hydrophobic surfaces without AB component (polycarbonate and polyethersulfone), these copolymers exhibited significant adsorption with a little dissipation at low concentrations. For hydrophilic surfaces with AB component (cellulose and borosilicate), the adsorption at low-surfactant concentration is low while dissipation is relatively high. Additionally, the chemical properties of Pluronics such as the ratio of PPO to PEO, along with the interaction of PPO with surfaces were observed to play a critical role in adsorption. Furthermore, the interfacial structure of the adsorbed layer was affected by both AB interaction and the presence of PEO block.

  9. In-can melting process and equipment development from 1974 to 1978

    International Nuclear Information System (INIS)

    Blair, H.T.

    1979-08-01

    Both the defense HLLW stores in tanks presently and the HLLW from proposed reprocessing of commercial LWR fuel can be vitrified as borosilicate glass in containers made of 300-series stainless steel by the ICM (in-can melting) process. Melting rates of 50 kg/h in 12-in.-dia cans and 117 kg/h in 28-in.-dia cans can be achieved in the ICM by using the rising-level charging method and internal heat-transfer plate assemblies in the cans. The ICM process can be monitored and remotely controlled without the aid of instrumentation attached to the waste can. The ICM process is compatible with both heated-wall spray calciners and fluidized-bed calciners. The ICM process causes residual tensile stresses as high as the yield strength in vitrified product containers made of 300-series stainless steel. Spall due to oxidation of the exterior of the can during an ICM process can be prevented by using an inert cover gas, by putting a protective coating on the can surface, or by using an oxidation-resistant alloy. Processing problems are minimized and product quality is improved when the complete can is located inside the furnace chamber by setting it on the hearth. A maximum of 24 kW and an average of 15 kW is required per 15-in.-high furnace zone to melt waste borosilicate glass at a rate of 117 kg/h in a 28-in.-dia ICM

  10. Description of processes for the immobilization of selected transuranic wastes

    International Nuclear Information System (INIS)

    Timmerman, C.L.

    1980-12-01

    Processed sludge and incinerator-ash wastes contaminated with transuranic (TRU) elements may require immobilization to prevent the release of these elements to the environment. As part of the TRU Waste Immobilization Program sponsored by the Department of Energy (DOE), the Pacific Northwest Laboratory is developing applicable waste-form and processing technology that may meet this need. This report defines and describes processes that are capable of immobilizing a selected TRU waste-stream consisting of a blend of three parts process sludge and one part incinerator ash. These selected waste streams are based on the compositions and generation rates of the waste processing and incineration facility at the Rocky Flats Plant. The specific waste forms that could be produced by the described processes include: in-can melted borosilicate-glass monolith; joule-heated melter borosilicate-glass monolith or marble; joule-heated melter aluminosilicate-glass monolith or marble; joule-heated melter basaltic-glass monolith or marble; joule-heated melter glass-ceramic monolith; cast-cement monolith; pressed-cement pellet; and cold-pressed sintered-ceramic pellet

  11. Characteristics of high-level radioactive waste forms for their disposal

    International Nuclear Information System (INIS)

    Kim, Seung Soo; Chun, Kwan Sik; Kang, Chul Hyung

    2000-12-01

    In order to develop a deep geological repository for a high-level radioactive waste coming from reprocessing of spent nuclear fuels discharged from our domestic nuclear power plants, the the required characteristics of waste form are dependent upon a solidifying medium and the amount of waste loading in the medium. And so, by the comparative analysis of the characteristics of various waste forms developed up to the present, a suitable medium is recommended.The overall characteristics of the latter is much better than those of the former, but the change of the properties due to an amorphysation by radiation exposure and its thermal expansion has not been clearly identified yet. And its process has not been commercialized. However, the overall properties of the borosilicate glass waste forms are acceptable for their disposal, their production cost is reasonable and their processes have already been commercialized. And plenty informations of their characteristics and operational experiences have been accumulated. Consequently, it is recommended that a suitable medium solidifying the HLW is a borosilicate glass and its composition for the identification of a reference waste form would be based on the glass frit of R7T7

  12. Initial Examination of Low Velocity Sphere Impact of Glass Ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Morrissey, Timothy G [ORNL; Fox, Ethan E [ORNL; Wereszczak, Andrew A [ORNL; Ferber, Mattison K [ORNL

    2012-06-01

    This report summarizes US Army TARDEC sponsored work at Oak Ridge National Laboratory (ORNL) involving low velocity (< 30 m/s or < 65 mph) sphere impact testing of two materials from the lithium aluminosilicate family reinforced with different amounts of ceramic particulate, i.e., glass-ceramic materials, SCHOTT Resistan{trademark}-G1 and SCHOTT Resistan{trademark}-L. Both materials are provided by SCHOTT Glass (Duryea, PA). This work is a follow-up to similar sphere impact studies completed by the authors on PPG's Starphire{reg_sign} soda-lime silicate glass and SCHOTT BOROFLOAT{reg_sign} borosilicate glass. A gas gun or a sphere-drop test setup was used to produce controlled velocity delivery of silicon nitride (Si{sub 3}N{sub 4}) spheres against the glass ceramic tile targets. Minimum impact velocities to initiate fracture in the glass-ceramics were measured and interpreted in context to the kinetic energy of impact and the elastic property mismatch between sphere and target material. Quasistatic spherical indentation was also performed on both glass ceramics and their contact damage responses were compared to those of soda-lime silicate and borosilicate glasses. Lastly, variability of contact damage response was assessed by performing spherical indentation testing across the area of an entire glass ceramic tile. The primary observations from this low velocity (< 30 m/s or < 65 mph) testing were: (1) Resistan{trademark}-L glass ceramic required the highest velocity of sphere impact for damage to initiate. Starphire{reg_sign} soda-lime silicate glass was second best, then Resistan{trademark}-G1 glass ceramic, and then BOROFLOAT{reg_sign} borosilicate glass. (2) Glass-ceramic Resistan{trademark}-L also required the largest force to initiate ring crack from quasi-static indentation. That ranking was followed, in descending order, by Starphire{reg_sign} soda-lime silicate glass, Resistan{trademark}-G1 glass ceramic, and BOROFLOAT{reg_sign} borosilicate glass

  13. Large Area and High Efficiency Photon Counting Imaging Detectors with High Time and Spatial Resolution for Night Time Sensing and Astronomy

    Science.gov (United States)

    Siegmund, O.; Vallerga, J.; Tremsin, A.; McPhate, J.; Frisch, H.; Elam, J.; Mane, A.; Wagner, R.; Varner, G.

    2012-09-01

    The development of large area photon counting, imaging, timing detectors with high performance has significance for applications in astronomy (such as our sensor on the SAAO SALT 10m telescope), night time remote reconnaissance, airborne/space situational awareness, and high-speed adaptive optics. Sealed tube configurations for optical/IR sensing also have applications in detection of Cherenkov light (RICH), biological single-molecule fluorescence lifetime imaging microscopy and neutron imaging applications. In open faced configurations these devices are important for UV and particle detection in space astrophysics, mass spectroscopy and many time-of flight applications. Currently available devices are limited to sizes of about 5 cm and use either conventional microchannel plates, or dynode multipliers for amplification, coupled coarse pad array readouts. Extension of these schemes to devices as large as 20 cm with high spatial resolution presents significant problems and potentially considerable cost. A collaboration (Large Area Picosecond Photon Detector) of the U. Chicago, Argonne National Laboratory, U.C. Berkeley, U. Hawaii and a number of other institutions has developed novel technologies to realize 20 cm format detectors in open face or sealed tube configurations. One critical component of this development is novel microchannel plates employing borosilicate micro-capillary arrays. The microchannel plates are based on a novel concept where the substrate is constructed from a borosilicate micro-capillary array that is made to function as a microchannel plate by deposition of resistive and secondary emissive layers using atomic layer deposition. The process is relatively inexpensive compared with conventional microchannel plates and allows very large microchannel plates to be produced with pore sizes as small as 10 microns. These provide many performance characteristics typical of conventional microchannel plates, but have been made in sizes up to 20 cm, have

  14. Evaluation of a high-throughput peptide reactivity format assay for assessment of the skin sensitization potential of chemicals

    Directory of Open Access Journals (Sweden)

    Chin Lin eWong

    2016-03-01

    Full Text Available The direct peptide reactivity assay (DPRA is a validated method for in vitro assessment of the skin sensitization potential of chemicals. In the present work, we describe a peptide reactivity assay using 96-well plate format and systematically identified the optimal assay conditions for accurate and reproducible classification of chemicals with known sensitizing capacity. The aim of the research is to ensure that the analytical component of the peptide reactivity assay is robust, accurate and reproducible in accordance with criteria that are used for the validation of bioanalytical methods. Analytical performance was evaluated using quality control samples (QCs; heptapeptides at low, medium and high concentrations and incubation of control chemicals (chemicals with known sensitization capacity, weak, moderate, strong, extreme and non-sensitizers with each of three synthetic heptapeptides, viz Cor1-C420 (Ac-NKKCDLF, cysteine- (Ac-RFAACAA and lysine- (Ac-RFAAKAA containing heptapeptides. The optimal incubation temperature for all three heptapeptides was 25°C. Apparent heptapeptide depletion was affected by vial material composition. Incubation of test chemicals with Cor1-C420, showed that peptide depletion was unchanged in polypropylene vials over 3-days storage in an autosampler but this was not the case for borosilicate glass vials. For cysteine-containing heptapeptide, the concentration was not stable by day 3 post-incubation in borosilicate glass vials. Although the lysine-containing heptapeptide concentration was unchanged in both polypropylene and borosilicate glass vials, the apparent extent of lysine-containing heptapeptide depletion by ethyl acrylate, differed between polypropylene (24.7% and glass (47.3% vials. Additionally, the peptide-chemical complexes for Cor1-C420-cinnamaldehyde and cysteine-containing heptapeptide-2,4-dinitrochlorobenzene were partially reversible during 3-days of autosampler storage. These observations further

  15. Evaluation of Diffuse Reflection Infrared Spectrometry for End-of-Shift Measurement of α-quartz in Coal Dust Samples.

    Science.gov (United States)

    Miller, Arthur L; Murphy, Nathaniel C; Bayman, Sean J; Briggs, Zachary P; Kilpatrick, Andrew D; Quinn, Courtney A; Wadas, Mackenzie R; Cauda, Emanuele G; Griffiths, Peter R

    2015-01-01

    The inhalation of toxic substances is a major threat to the health of miners, and dust containing respirable crystalline silica (α-quartz) is of particular concern, due to the recent rise in cases of coal workers' pneumoconiosis and silicosis in some U.S. mining regions. Currently, there is no field-portable instrument that can measure airborne α-quartz and give miners timely feedback on their exposure. The U.S. National Institute for Occupational Safety and Health (NIOSH) is therefore conducting studies to investigate technologies capable of end-of-shift or real-time measurement of airborne quartz. The present study focuses on the potential application of Fourier transform infrared (FT-IR) spectrometry conducted in the diffuse reflection (DR) mode as a technique for measuring α-quartz in respirable mine dust. A DR accessory was used to analyze lab-generated respirable samples of Min-U-Sil 5 (which contains more than 90% α-quartz) and coal dust, at mass loadings in the ranges of 100-600 μg and 600-5300 μg, respectively. The dust samples were deposited onto three different types of filters, borosilicate fiberglass, nylon, and polyvinyl chloride (PVC). The reflectance, R, was calculated by the ratio of a blank filter and a filter with deposited mine dust. Results suggest that for coal and pure quartz dusts deposited on 37 mm PVC filters, measurements of -log R correlate linearly with known amounts of quartz on filters, with R(2) values of approximately 0.99 and 0.94, respectively, for samples loaded up to ∼4000 μg. Additional tests were conducted to measure quartz in coal dusts deposited onto the borosilicate fiberglass and nylon filter media used in the NIOSH-developed Personal Dust Monitor (PDM). The nylon filter was shown to be amenable to DR analysis, but quantification of quartz is more accurate when the filter is "free," as opposed to being mounted in the PDM filter holder. The borosilicate fiberglass filters were shown to produce excessive

  16. Reduction of Glass Surface Reflectance by Ion Beam Surface Modification

    Energy Technology Data Exchange (ETDEWEB)

    Mark Spitzer

    2011-03-11

    This is the final report for DOE contract DE-EE0000590. The purpose of this work was to determine the feasibility of the reduction of the reflection from the front of solar photovoltaic modules. Reflection accounts for a power loss of approximately 4%. A solar module having an area of one square meter with an energy conversion efficiency of 18% generates approximately 180 watts. If reflection loss can be eliminated, the power output can be increased to 187 watts. Since conventional thin-film anti-reflection coatings do not have sufficient environmental stability, we investigated the feasibility of ion beam modification of the glass surface to obtain reduction of reflectance. Our findings are generally applicable to all solar modules that use glass encapsulation, as well as commercial float glass used in windows and other applications. Ion implantation of argon, fluorine, and xenon into commercial low-iron soda lime float glass, standard float glass, and borosilicate glass was studied by implantation, annealing, and measurement of reflectance. The three ions all affected reflectance. The most significant change was obtained by argon implantation into both low-iron and standard soda-lime glass. In this way samples were formed with reflectance lower than can be obtained with a single-layer coatings of magnesium fluoride. Integrated reflectance was reduced from 4% to 1% in low-iron soda lime glass typical of the glass used in solar modules. The reduction of reflectance of borosilicate glass was not as large; however borosilicate glass is not typically used in flat plate solar modules. Unlike conventional semiconductor ion implantation doping, glass reflectance reduction was found to be tolerant to large variations in implant dose, meaning that the process does not require high dopant uniformity. Additionally, glass implantation does not require mass analysis. Simple, high current ion implantation equipment can be developed for this process; however, before the process

  17. Optically transparent, mechanically durable, nanostructured superhydrophobic surfaces enabled by spinodally phase-separated glass thin films

    International Nuclear Information System (INIS)

    Aytug, Tolga; Simpson, John T; Lupini, Andrew R; Trejo, Rosa M; Jellison, Gerald E; Ivanov, Ilia N; Pennycook, Stephen J; Hillesheim, Daniel A; Winter, Kyle O; Christen, David K; Hunter, Scott R; Allen Haynes, J

    2013-01-01

    We describe the formation and properties of atomically bonded, optical quality, nanostructured thin glass film coatings on glass plates, utilizing phase separation by spinodal decomposition in a sodium borosilicate glass system. Following deposition via magnetron sputtering, thermal processing and differential etching, these coatings are structurally superhydrophilic (i.e., display anti-fogging functionality) and demonstrate robust mechanical properties and superior abrasion resistance. After appropriate chemical surface modification, the surfaces display a stable, non-wetting Cassie–Baxter state and exhibit exceptional superhydrophobic performance, with water droplet contact angles as large as 172°. As an added benefit, in both superhydrophobic and superhydrophilic states these nanostructured surfaces can block ultraviolet radiation and can be engineered to be anti-reflective with broadband and omnidirectional transparency. Thus, the present approach could be tailored toward distinct coatings for numerous markets, such as residential windows, windshields, specialty optics, goggles, electronic and photovoltaic cover glasses, and optical components used throughout the US military. (paper)

  18. Letter report: Evaluation of LFCM off-gas system technologies for the HWVP

    Energy Technology Data Exchange (ETDEWEB)

    Goles, R.W.; Mishima, J.; Schmidt, A.J.

    1996-03-01

    Radioactive high-level liquid waste (HLLW), a byproduct of defense nuclear fuel reprocessing activities, is currently being stored in underground tanks at several US sites. Because its mobility poses significant environmental risks, HLLW is not a suitable waste form for long-term storage. Thus, high-temperature processes for solidifying and isolating the radioactive components of HLLW have been developed and demonstrated by the US Department of Energy (DOE) and its contractors. Vitrification using liquidfed ceramic melters (LFCMs) is the reference process for converting US HLLW into a borosilicate glass. Two vitrification plants are currently under construction in the United States: the West Valley Demonstration Plant (WVDP) being built at the former West Valley Nuclear Fuels Services site in West Valley, New York; and the Defense Waste Processing Facility (DWPF), which is currently 85% complete at DOE`s Savannah River Plant (SRP). A third facility, the Hanford Waste Vitrification Plant (HWVP), is being designed at DOE`s Hanford Site.

  19. Glass formulation for phase 1 high-level waste vitrification

    International Nuclear Information System (INIS)

    Vienna, J.D.; Hrma, P.R.

    1996-04-01

    The purpose of this study is to provide potential glass formulations for prospective Phase 1 High-Level Waste (HLW) vitrification at Hanford. The results reported here will be used to aid in developing a Phase 1 HLW vitrification request for proposal (RFP) and facilitate the evaluation of ensuing proposals. The following factors were considered in the glass formulation effort: impact on total glass volume of requiring the vendor to process each of the tank compositions independently versus as a blend; effects of imposing typical values of B 2 O 3 content and waste loading in HLW borosilicate glasses as restrictions on the vendors (according to WAPS 1995, the typical values are 5--10 wt% B 2 O 3 and 20--40 wt% waste oxide loading); impacts of restricting the processing temperature to 1,150 C on eventual glass volume; and effects of caustic washing on any of the selected tank wastes relative to glass volume

  20. Vitrification of reactor wastes

    Energy Technology Data Exchange (ETDEWEB)

    Jouan, A. [CEA Centre d`Etudes de la Vallee du Rhone, 30 - Marcoule (France). Dept. des Procedes de Retraitement; Sussmilch, J. [Nuclear Research Institut, Rez (Czech Republic)

    1993-12-31

    The vitrification of low and intermediate level wastes from the NPP operation has been studied in the frame of a Franco-Czech agreement. The laboratory experiments concentrated on a search for a suitable borosilicate glass matrix which could incorporate relatively high quantities of boron and sodium, main components of liquid wastes from the WWER reactor type NPPs. A relatively wide area of waste compositions has been studied and properties of glasses suitable for the technology and waste disposal were measured. Great attention has been paid to the chemical stability (leachability), other properties like thermal dependence of viscosity and electrical conductivity of melts, and the microstructure of the final solidification product have also been evaluated. The feasibility of the vitrification process has been proved during pilot plant tests which were accomplished at the French establishment in Marcoule. The results of tests were promising. (authors). 4 tabs., 7 figs.

  1. Vitrification of reactor wastes

    International Nuclear Information System (INIS)

    Jouan, A.

    1993-01-01

    The vitrification of low and intermediate level wastes from the NPP operation has been studied in the frame of a Franco-Czech agreement. The laboratory experiments concentrated on a search for a suitable borosilicate glass matrix which could incorporate relatively high quantities of boron and sodium, main components of liquid wastes from the WWER reactor type NPPs. A relatively wide area of waste compositions has been studied and properties of glasses suitable for the technology and waste disposal were measured. Great attention has been paid to the chemical stability (leachability), other properties like thermal dependence of viscosity and electrical conductivity of melts, and the microstructure of the final solidification product have also been evaluated. The feasibility of the vitrification process has been proved during pilot plant tests which were accomplished at the French establishment in Marcoule. The results of tests were promising. (authors). 4 tabs., 7 figs

  2. Advances in microchannel plates and photocathodes for ultraviolet photon counting detectors

    Science.gov (United States)

    Siegmund, O. H. W.; Fujiwara, K.; Hemphill, R.; Jelinsky, S. R.; McPhate, J. B.; Tremsin, A. S.; Vallerga, J. V.; Frisch, H. J.; Elam, J.; Mane, A.; Bennis, D. C.; Craven, C. A.; Deterando, M. A.; Escolas, J. R.; Minot, M. J.; Renaud, J. M.

    2011-09-01

    A new method of fabricating microchannel plates has been investigated, employing microcapillary arrays of borosilicate glass that are deposited with resistive and secondary emissive layers using atomic layer deposition. Microchannel plates of this kind have been made in sizes from 33 mm to 200 mm, with pore sizes of 40 μm and 20 μm, pore length to diameter ratios of 60:1, bias angles of 8°, and open areas from 60% to 83%. Tests with single MCPs and MCP pairs have been done and show good imaging quality, gain comparable to conventional MCPs, low background rates (~ 0.085 events sec-1 cm-2), fast pulse response, and good ageing characteristics. The quantum efficiency for bare and alkali halide coated MCPs is similar to conventional MCPs, and we have also been able to deposit opaque GaN(Mg) cathodes directly onto these MCPs.

  3. Behavior of technetium in nuclear waste vitrification processes.

    Science.gov (United States)

    Pegg, Ian L

    Nearly 100 tests were performed with prototypical melters and off-gas system components to investigate the extents to which technetium is incorporated into the glass melt, partitioned to the off-gas stream, and captured by the off-gas treatment system components during waste vitrification. The tests employed several simulants, spiked with 99m Tc and Re (a potential surrogate), of the low activity waste separated from nuclear wastes in storage in the Hanford tanks, which is planned for immobilization in borosilicate glass. Single-pass technetium retention averaged about 35 % and increased significantly with recycle of the off-gas treatment fluids. The fraction escaping the recycle loop was very small.

  4. A Miniature Graphene-based Biosensor for Intracellular Glucose Measurements

    International Nuclear Information System (INIS)

    Hasan, Kamran ul; Asif, Muhammad H.; Hassan, Muhammad Umair; Sandberg, Mats O.; Nur, O.; Willander, M.; Fagerholm, Siri; Strålfors, Peter

    2015-01-01

    We report on a small and simple graphene-based potentiometric sensor for the measurement of intracellular glucose concentration. A fine borosilicate glass capillary coated with graphene and subsequently immobilized with glucose oxidase (GOD) enzyme is inserted into the intracellular environment of a single human cell. The functional groups on the edge plane of graphene assist the attachment with the free amine terminals of GOD enzyme, resulting in a better immobilization. The sensor exhibits a glucose-dependent electrochemical potential against an Ag/AgCl reference microelectrode which is linear across the whole concentration range of interest (10 – 1000 μM). Glucose concentration in human fat cell measured by our graphene-based sensor is in good agreement with nuclear magnetic resonance (NMR) spectroscopy

  5. X-ray photoemission spectroscopy and ion backscattering analysis of leached simulated waste glass containing UO3

    International Nuclear Information System (INIS)

    Karim, D.P.; Lam, D.J.

    1980-01-01

    UO 3 has been dissolved into several complex borosilicate glasses including Battelle simulated waste glasses 76-68, 3008, and 76-101. The glass surfaces were examined before and after leaching using x-ray photoemission spectroscopy and backscattered ion beam profiling. Samples leached in distilled water showed enhanced surface layer concentrations of several elements including uranium, titanium, zinc, iron and rare earths. For the case of uranium in 76-101, a simple experiment involving leaching two glasses in the same container showed that this surface enhancement is probably not due to redeposition from solution. Similar samples behaved quite differently when leached in a pH = 3.5 nitric acid solution, showing a surface layer high in SiO 2

  6. Thermal Protection Supplement for Reducing Interface Thermal Mismatch

    Science.gov (United States)

    Stewart, David A. (Inventor); Leiser, Daniel B. (Inventor)

    2017-01-01

    A thermal protection system that reduces a mismatch of thermal expansion coefficients CTE between a first material layer (CTE1) and a second material layer (CTE2) at a first layer-second layer interface. A portion of aluminum borosilicate (abs) or another suitable additive (add), whose CTE value, CTE(add), satisfies (CTE(add)-CTE1)(CTE(add)-CTE2)<0, is distributed with variable additive density,.rho.(z;add), in the first material layer and/or in the second material layer, with.rho.(z;add) near the materials interface being relatively high (alternatively, relatively low) and.rho.(z;add) in a region spaced apart from the interface being relatively low (alternatively, relatively high).

  7. A novel TiO{sub 2}-assisted solar photocatalytic batch-process disinfection reactor for the treatment of biological and chemical contaminants in domestic drinking water in developing countries

    Energy Technology Data Exchange (ETDEWEB)

    Duffy, E.F.; Al Touati, F. [Royal College of Surgeons in Ireland, Dublin (Ireland). Dept. of Chemistry and Physics; Kehoe, S.C. [Royal College of Surgeons in Ireland, Dublin (IE). Dept. of Surgery] (and others)

    2004-11-01

    The technical feasibility and performance of photocatalytic TiO{sub 2} coatings in batch-process solar disinfection (SODIS) reactors to improve potability of drinking water in developing countries have been studied. Borosilicate glass and PET plastic SODIS reactors fitted with flexible plastic inserts coated with TiO{sub 2} powder were shown to be 20% and 25% more effective, respectively, than standard SODIS reactors for the inactivation of E. coli K12. Isopropanol at 100 ppm concentration levels was observed to be completely photodegraded after 24 h continuous exposure to 100 mW/cm{sup 2} simulated sunlight in a similar solar photocatalytic disinfector (SPC-DIS) reactor. The technique for producing the TiO{sub 2}-coated plastic inserts is described and demonstrated to be an appropriate and affordable technology for developing countries. (Author)

  8. Incubation of human blood fractions leads to changes in apparent miRNA abundance

    DEFF Research Database (Denmark)

    Skovgaard, Kerstin; Jørgensen, Stine Thuen; Heegaard, Peter M. H.

    was performed. 19 specific miRNAs were compared in control samples (0 hours), incubated 24 hour samples, and incubated 24 hour samples with glass bead stimulation for each blood fraction. All 19 miRNAs were expressed in all blood fractions albeit at different levels for different miRNAs. Incubation resulted...... in plasma, RBC, PBMC and PMN, while expression of miR-25, miR15a, miR-126 and miR223 was significantly changed in PRP. Thus, PRP, as the only blood fraction depended on stimulation to change its miRNA profile upon incubation. For the other fractions, stimulation either leveled out the changes induced......A basic investigation on the presence and composition of miRNA species and their reaction to in vitro incubation and stimulation (borosilicate glass beads), in plasma, platelet-rich plasma (PRP), red blood cells (RBC), peripheral blood mononuclear cells (PBMC) and polymorphonuclear (PMN) cells...

  9. Oxidation of BN-coated SiC fibers in ceramic matrix composites

    International Nuclear Information System (INIS)

    Sheldon, B.W.; Sun, E.Y.

    1996-01-01

    Thermodynamic calculations were performed to analyze the simultaneous oxidation of BN and SiC. The results show that, with limited amounts of oxygen present, the formation of SiO 2 should occur prior to the formation of B 2 O 3 . This agrees with experimental observations of oxidation in glass-ceramic matrix composites with BN-coated SiC fibers, where a solid SiO 2 reaction product containing little or no boron has been observed. The thermodynamic calculations suggest that this will occur when the amount of oxygen available is restricted. One possible explanation for this behavior is that SiO 2 formation near the external surfaces of the composite closes off cracks or pores, such that vapor phase O 2 diffusion into the composite occurs only for a limited time. This indicates that BN-coated SiC fibers will not always oxidize to form significant amounts of a low-melting, borosilicate glass

  10. A mathematical model for surface roughness of fluidic channels produced by grinding aided electrochemical discharge machining (G-ECDM

    Directory of Open Access Journals (Sweden)

    Ladeesh V. G.

    2017-01-01

    Full Text Available Grinding aided electrochemical discharge machining is a hybrid technique, which combines the grinding action of an abrasive tool and thermal effects of electrochemical discharges to remove material from the workpiece for producing complex contours. The present study focuses on developing fluidic channels on borosilicate glass using G-ECDM and attempts to develop a mathematical model for surface roughness of the machined channel. Preliminary experiments are conducted to study the effect of machining parameters on surface roughness. Voltage, duty factor, frequency and tool feed rate are identified as the significant factors for controlling surface roughness of the channels produced by G-ECDM. A mathematical model was developed for surface roughness by considering the grinding action and thermal effects of electrochemical discharges in material removal. Experiments are conducted to validate the model and the results obtained are in good agreement with that predicted by the model.

  11. The hot bench scale plant Ester for the vitrification of high level wastes

    International Nuclear Information System (INIS)

    Nannicini, R.; Strazzer, A.; Cantale, C; Donato, A.; Grossi, G.

    1985-01-01

    In this paper the hot bench-scale plant ESTER for the vitrification of the high-level radioactive wastes is described, and the main results of the first radioactive campaign are reported. The ESTER plant, which is placed in the ADECO-ESSOR hot cells of the C.C.R.-EURATOM-ISPRA, has been built and is operated by the ENEA, Departement of Fuel Cycle. It began operating with real radioactive wastes about 1 year ago, solidifying a total of 12 Ci of fission products into 2,02 Kg of borosilicate glass, corresponding to 757 ml of glass. During the vitrification many samples of liquid and gaseous streams have been taken and analyzed. A radioactivity balance in the plant has been calculated, as well as a mass balance of nitrates and of the 137 Cs and 106 Ru volatized in the process

  12. Planar patch-clamp force microscopy on living cells

    Energy Technology Data Exchange (ETDEWEB)

    Pamir, Evren [Center for Nano Science, Ludwig-Maximilians University, Amalienstr 54, 80799 Munich (Germany); George, Michael; Fertig, Niels [Nanion Technologies GmbH, Erzgiessereistr. 4, 80335 Munich (Germany); Benoit, Martin [Center for Nano Science, Ludwig-Maximilians University, Amalienstr 54, 80799 Munich (Germany)], E-mail: martin.benoit@physik.uni-muenchen.de

    2008-05-15

    Here we report a new combination of the patch-clamp technique with the atomic force microscope (AFM). A planar patch-clamp chip microstructured from borosilicate glass was used as a support for mechanical probing of living cells. The setup not only allows for immobilizing even a non-adherent cell for measurements of its mechanical properties, but also for simultaneously measuring the electrophysiological properties of a single cell. As a proof of principle experiment we measured the voltage-induced membrane movement of HEK293 and Jurkat cells in the whole-cell voltage clamp configuration. The results of these measurements are in good agreement with previous studies. By using the planar patch-clamp chip for immobilization, the AFM not only can image non-adhering cells, but also gets easily access to an electrophysiologically controlled cellular probe at low vibrational noise.

  13. Iron Phosphate Glasses: An Alternative for Vitrifying Certain Nuclear Wastes

    International Nuclear Information System (INIS)

    Day, Delbert E.; Ray, Chandra S.; Cheol-Woon Kim

    2004-01-01

    Vitrification of nuclear waste in a glass is currently the preferred process for waste disposal. DOE currently approves only borosilicate (BS) type glasses for such purposes. However, many nuclear wastes, presently awaiting disposal, have complex and diverse chemical compositions, and often contain components that are poorly soluble or chemically incompatible in BS glasses. Such problematic wastes can be pre-processed and/or diluted to compensate for their incompatibility with a BS glass matrix, but both of these solutions increases the wasteform volume and the overall cost for vitrification. Direct vitrification using alternative glasses that utilize the major components already present in the waste is preferable, since it avoids pre-treating or diluting the waste, and, thus, minimizes the wasteform volume and overall cost

  14. Letter report: Evaluation of LFCM off-gas system technologies for the HWVP

    International Nuclear Information System (INIS)

    Goles, R.W.; Mishima, J.; Schmidt, A.J.

    1996-03-01

    Radioactive high-level liquid waste (HLLW), a byproduct of defense nuclear fuel reprocessing activities, is currently being stored in underground tanks at several US sites. Because its mobility poses significant environmental risks, HLLW is not a suitable waste form for long-term storage. Thus, high-temperature processes for solidifying and isolating the radioactive components of HLLW have been developed and demonstrated by the US Department of Energy (DOE) and its contractors. Vitrification using liquidfed ceramic melters (LFCMs) is the reference process for converting US HLLW into a borosilicate glass. Two vitrification plants are currently under construction in the United States: the West Valley Demonstration Plant (WVDP) being built at the former West Valley Nuclear Fuels Services site in West Valley, New York; and the Defense Waste Processing Facility (DWPF), which is currently 85% complete at DOE's Savannah River Plant (SRP). A third facility, the Hanford Waste Vitrification Plant (HWVP), is being designed at DOE's Hanford Site

  15. Pair distribution functions of amorphous organic thin films from synchrotron X-ray scattering in transmission mode

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Chenyang; Teerakapibal, Rattavut; Yu, Lian; Zhang, Geoff G. Z.

    2017-07-10

    Using high-brilliance high-energy synchrotron X-ray radiation, for the first time the total scattering of a thin organic glass film deposited on a strongly scattering inorganic substrate has been measured in transmission mode. The organic thin film was composed of the weakly scattering pharmaceutical substance indomethacin in the amorphous state. The film was 130 µm thick atop a borosilicate glass substrate of equal thickness. The atomic pair distribution function derived from the thin-film measurement is in excellent agreement with that from bulk measurements. This ability to measure the total scattering of amorphous organic thin films in transmission will enable accuratein situstructural studies for a wide range of materials.

  16. Topological Approach for Predicting the Properties of Glasses

    DEFF Research Database (Denmark)

    Smedskjær, Morten Mattrup; Mauro, John C.; Yue, Yuanzheng

    and M.F. Thorpe around 1980. By further including the Gupta-Mauro temperature dependence of the constraints, the composition dependence of properties such as hardness and viscosity can be quantitatively predicted for oxide network glasses of industrial interest, such as borates and borosilicates......Predicting the properties of new materials prior to manufacturing is a topic attracting great industrial and scientific interest. Property prediction for ceramic materials is facilitated by the periodic short- and long-range order of crystals. However, for glassy systems the lack of long......-range order and the long time scales for relaxation greatly complicate the traditional modeling efforts. We show that the key for making progress has been to extract the key physics governing the macroscopic properties by using topological constraint theory, which was originally developed by J.C. Phillips...

  17. Lessons learned from the development and manufacture of ceramic reusable surface insulation materials for the space shuttle orbiters

    Science.gov (United States)

    Banas, R. P.; Elgin, D. R.; Cordia, E. R.; Nickel, K. N.; Gzowski, E. R.; Aguiler, L.

    1983-01-01

    Three ceramic, reusable surface insulation materials and two borosilicate glass coatings were used in the fabrication of tiles for the Space Shuttle orbiters. Approximately 77,000 tiles were made from these materials for the first three orbiters, Columbia, Challenger, and Discovery. Lessons learned in the development, scale up to production and manufacturing phases of these materials will benefit future production of ceramic reusable surface insulation materials. Processing of raw materials into tile blanks and coating slurries; programming and machining of tiles using numerical controlled milling machines; preparing and spraying tiles with the two coatings; and controlling material shrinkage during the high temperature (2100-2275 F) coating glazing cycles are among the topics discussed.

  18. Waste acceptance product specifications for vitrified high-level waste forms

    International Nuclear Information System (INIS)

    Applewhite-Ramsey, A.; Sproull, J.F.

    1993-01-01

    The Nuclear Waste Policy Act of 1982 mandated that all high-level waste (HLW) be sent to a federal geologic repository for permanent disposal. DOE published the Environmental Assessment in 1982 which identified borosilicate glass as the chosen HLW form. 1 In 1985 the Department of Energy instituted a Waste Acceptance Process to assure that DWPF glass waste forms would be acceptable to such a repository. This assurance was important since production of waste forms will precede repository construction and licensing. As part of this Waste Acceptance Process, the DOE Office of Civilian Radioactive Waste Management (RW) formed the Waste Acceptance Committee (WAC). The WAC included representatives from the candidate repository sites, the waste producing sites and DOE. The WAC was responsible for developing the Waste Acceptance Preliminary Specifications (WAPS) which defined the requirements the waste forms must meet to be compatible with the candidate repository geologies

  19. Shear Brillouin light scattering microscope.

    Science.gov (United States)

    Kim, Moonseok; Besner, Sebastien; Ramier, Antoine; Kwok, Sheldon J J; An, Jeesoo; Scarcelli, Giuliano; Yun, Seok Hyun

    2016-01-11

    Brillouin spectroscopy has been used to characterize shear acoustic phonons in materials. However, conventional instruments had slow acquisition times over 10 min per 1 mW of input optical power, and they required two objective lenses to form a 90° scattering geometry necessary for polarization coupling by shear phonons. Here, we demonstrate a confocal Brillouin microscope capable of detecting both shear and longitudinal phonons with improved speeds and with a single objective lens. Brillouin scattering spectra were measured from polycarbonate, fused quartz, and borosilicate in 1-10 s at an optical power level of 10 mW. The elastic constants, phonon mean free path and the ratio of the Pockels coefficients were determined at microscopic resolution.

  20. Pair distribution functions of amorphous organic thin films from synchrotron X-ray scattering in transmission mode

    Directory of Open Access Journals (Sweden)

    Chenyang Shi

    2017-09-01

    Full Text Available Using high-brilliance high-energy synchrotron X-ray radiation, for the first time the total scattering of a thin organic glass film deposited on a strongly scattering inorganic substrate has been measured in transmission mode. The organic thin film was composed of the weakly scattering pharmaceutical substance indomethacin in the amorphous state. The film was 130 µm thick atop a borosilicate glass substrate of equal thickness. The atomic pair distribution function derived from the thin-film measurement is in excellent agreement with that from bulk measurements. This ability to measure the total scattering of amorphous organic thin films in transmission will enable accurate in situ structural studies for a wide range of materials.

  1. Study of neutron absorbing microspheres in research reactors - Metal systems wear

    International Nuclear Information System (INIS)

    Gana Watkins, Ignacio A.; Silin, Nicolas; Prado, Miguel O.; Mazufri, Claudio

    2012-01-01

    Now-a-days, it is increasingly common for nuclear power plants, as well as research reactors, to be designed and built with an alternative safety system aside from control rods. The acids and/or salts in solution injection systems is most frequently used. However, these systems present several implementation and operation problems due to the physical and chemical properties of the used compounds. After analyzing these drawbacks, we developed a new alternative safety system that contains the absorbing element isolated from the aqueous medium. In this context, it's proposed the use of aluminum borosilicate microspheres. The current paper presents erosion wear experiments to determine under which conditions microspheres can be considered as a potential component of a secondary shut down system in a nuclear facility (author))

  2. Fabrication and characterization of MCC [Materials Characterization Center] approved testing material---ATM-2, ATM-3, and ATM-4 glasses

    International Nuclear Information System (INIS)

    Wald, J.W.

    1988-03-01

    Materials Characterization Center glasses ATM-2, ATM-3, and ATM-4 are designed to simulate high-level waste glasses that are likely to result from the reprocessing of commercial nuclear reactor fuels. The three Approved Testing Materials (ATMs) are borosilicate glasses based upon the MCC-76-68 glass composition. One radioisotope was added to form each ATM. The radioisotopes added to form ATM-2, ATM-3, and ATM-4 were 241 Am, 237 Np, and 239 Pu, respectively. Each of the ATM lots was produced in a nominal lot size of 450 g from feed stock melted in a nitrogen-atmosphere glove box at 1200/degree/C in a platinum crucible. Each ATM was then cast into bars. Analyzed compositions of these glasses are listed. The nonradioactive elements were analyzed by inductively coupled argon plasma atomic emission spectroscopy (ICP), and the radioisotope analyses were done by alpha energy analysis. Results are discussed. 7 refs., 3 figs., 5 tabs

  3. Composite quarterly technical report: long-term high-level waste technology, October-December 1980

    International Nuclear Information System (INIS)

    Cornman, W.R.

    1981-04-01

    The technical information in this report summarizes work performed at participating sites to immobilize high-level radioactive wastes. The areas reported are in: program management and support; waste preparation; waste fixation; and final handling. Majority of the studies were in the area of waste fixation, some of which are: leaching tests of ceramic forms, high silica glass, graphite powder and other carbon preparations; viscosity measurements for a range of waste-glass compositions from references borosilicate glass to high-alumina glasses; neutron activation analysis for measuring leach rates; preparation of SYNROC D spheres; formulations for preparing ceramics from defense waste composition; development of a pilot-scale glass melter, and kinetic studies of slag formation in glass melters

  4. U.S. program assessing nuclear waste disposal in space - A status report

    Science.gov (United States)

    Rice, E. E.; Priest, C. C.; Friedlander, A. L.

    1980-01-01

    Various concepts for the space disposal of nuclear waste are discussed, with attention given to the destinations now being considered (high earth orbit, lunar orbit, lunar surface, solar orbit, solar system escape, sun). Waste mixes are considered in the context of the 'Purex' (Plutonium and Uranium extraction) process and the potential forms for nuclear waste disposal (ORNL cermet, Boro-silicate glass, Metal matrix, Hot-pressed supercalcine) are described. Preliminary estimates of the energy required and the cost surcharge needed to support the space disposal of nuclear waste are presented (8 metric tons/year, requiring three Shuttle launches). When Purex is employed, the generated electrical energy needed to support the Shuttle launches is shown to be less than 1%, and the projected surcharge to electrical users is shown to be slightly more than two mills/kW-hour.

  5. Evaluation of the mixing system for the West Valley melter feed hold tank

    Energy Technology Data Exchange (ETDEWEB)

    Fow, C.L.; Kurath, D.E.; Pulsipher, B.A.

    1989-01-01

    High-level radioactive liquid wastes are currently stored in underground tanks at several Department of Energy facilities. The current plan for management of these wastes is to convert them to a durable borosilicate glass, then isolate the glass in a deep geologic repository. The process for converting the wastes to glass involves mixing the high-level wastes with glass-forming chemicals, then transforming the resulting slurry into glass using a high-temperature furnace known as a slurry-fed ceramic melter. Maintaining the quality of the glass product and proficient melter operation depends on the ability of the waste slurry preparation and feed systems to produce and maintain a homogeneous mixture of waste and glass-former materials. This document reviews current technology. 11 refs., 18 figs., 15 tabs.

  6. Defense waste processing facility precipitate hydrolysis process

    International Nuclear Information System (INIS)

    Doherty, J.P.; Eibling, R.E.; Marek, J.C.

    1986-03-01

    Sodium tetraphenylborate and sodium titanate are used to assist in the concentration of soluble radionuclide in the Savannah River Plant's high-level waste. In the Defense Waste Processing Facility, concentrated tetraphenylborate/sodium titanate slurry containing cesium-137, strontium-90 and traces of plutonium from the waste tank farm is hydrolyzed in the Salt Processing Cell forming organic and aqueous phases. The two phases are then separated and the organic phase is decontaminated for incineration outside the DWPF building. The aqueous phase, containing the radionuclides and less than 10% of the original organic, is blended with the insoluble radionuclides in the high-level waste sludge and is fed to the glass melter for vitrification into borosilicate glass. During the Savannah River Laboratory's development of this process, copper (II) was found to act as a catalyst during the hydrolysis reactions, which improved the organic removal and simplified the design of the reactor

  7. Superconducting open-gradient magnetic separation for the pretreatment of radioactive or mixed waste vitrification feeds. 1998 annual progress report

    International Nuclear Information System (INIS)

    Crawford, C.; Doctor, R.D.; Landsberger, S.; Nunez, L.; Ritter, J.

    1998-01-01

    'The objective is to reduce the volume and cost of high-level waste glass produced during US DOE remediation activities by demonstrating that magnetic separation can separate crystalline, amorphous, and colloidal constituents in vitrification feed streams known to be deleterious to the production of borosilicate glass. Magnetic separation will add neither chemicals nor generate secondary waste streams. The project includes the systematic study of magnetic interactions of waste constituents under controlled physical and chemical conditions (e.g., hydration, oxidation, temperature) to identify mechanisms that control the magnetic properties. Partitioning of radionuclides to determine their sorption mechanisms is also being studied. The identification of fundamental magnetic properties within the microscopic chemical environment in combination with hydrodynamic and electrodynamic models provides insights into the design of a system for optimal separation. Following this, experimental studies using superconducting open-gradient magnetic separation (OGMS) will be conducted to validate its effectiveness as a pretreatment technique.'

  8. Vitrification of F006 plating waste sludge by Reactive Additive Stabilization Process (RASP)

    International Nuclear Information System (INIS)

    Martin, H.L.; Jantzen, C.M.; Pickett, J.B.

    1994-01-01

    Solidification into glass of nickel-on-uranium plating wastewater treatment plant sludge (F006 Mixed Waste) has been demonstrated at the Savannah River She (SRS). Vitrification using high surface area additives, the Reactive Additive Stabilization Process (RASP), greatly enhanced the solubility and retention of heavy metals In glass. The bench-scale tests using RASP achieved 76 wt% waste loading In both soda-lime-silica and borosilicate glasses. The RASP has been Independently verified by a commercial waste management company, and a contract awarded to vitrify the approximately 500,000 gallons of stored waste sludge. The waste volume reduction of 89% will greatly reduce the disposal costs, and delisting of the glass waste is anticipated. This will be the world's first commercial-scale vitrification system used for environmental cleanup of Mixed Waste. Its stabilization and volume reduction abilities are expected to set standards for the future of the waste management Industry

  9. Chemical durability of soda-lime-aluminosilicate glass for radioactive waste vitrification

    International Nuclear Information System (INIS)

    Eppler, F.H.; Yim, M.S.

    1998-01-01

    Vitrification has been identified as one of the most viable waste treatment alternatives for nuclear waste disposal. Currently, the most popular glass compositions being selected for vitrification are the borosilicate family of glasses. Another popular type that has been around in glass industry is the soda-lime-silicate variety, which has often been characterized as the least durable and a poor candidate for radioactive waste vitrification. By replacing the boron constituent with a cheaper substitute, such as silica, the cost of vitrification processing can be reduced. At the same time, addition of network intermediates such as Al 2 O 3 to the glass composition increases the environmental durability of the glass. The objective of this study is to examine the ability of the soda-lime-aluminosilicate glass as an alternative vitrification tool for the disposal of radioactive waste and to investigate the sensitivity of product chemical durability to variations in composition

  10. Degradação do pesticida Padron® por processos fotoquímicos utilizando luz artificial e solar Degradation of Padron® by photochemical processes using artificial and sunlight radiation

    Directory of Open Access Journals (Sweden)

    Silvio César Godinho Teixeira

    2007-01-01

    Full Text Available Destruction of Padron® (dye and picloram was evaluated using a photoreactor and a solar reactor. Photolysis was observed using only a germicide lamp (GL. Black light (BL and H2O2 (172 mmol L-1 promoted a conversion of 49% and 6% of dye and picloram, respectively. Photocatalytic processes were more efficient using TiO2/GL (96%-dye; 60%-picloram than TiO2/BL (44%-dye; 40%-picloram. Photolysis using sunlight was not observed during PadronÒ recirculation in the reactor constructed with four borosilicate tubes. Meanwhile, adding H2O2 resulted in 12% conversion of dissolved organic compounds. Finally, the most efficient mineralization (60% was obtained using the Fenton reaction ( H2O2-176 mmol L-1; FeSO4x6H2O-90 mmol L-1 and sunlight.

  11. Effects of interfaces on nano-friction of vertically aligned multi-walled carbon nanotube arrays

    International Nuclear Information System (INIS)

    Lou, J.; Kim, K.-S.

    2008-01-01

    Sliding friction properties of vertically aligned multi-walled carbon nanotube (VAMWNT) arrays have been investigated in current study in a quantitative manner. The VAMWNT arrays have been fabricated on an anodic aluminum oxide template by chemical vapor deposition at 650 deg. C. Friction force was measured in air by a modified atomic force microscopy (AFM) cantilever-bead assembly with 15 μm diameter borosilicate sphere attached to the end of the regular AFM cantilever. Quantitative measurements were achieved by using a novel in situ calibration methods recently developed based on diamagnetic levitation [Q. Li, K.-S. Kim, A. Rydberg, Rev. Sci. Instrum. 77 (2006) 065105-1-13]. The effects of different interfaces were studied using both cantilever-bead assembly coated with and without Al thin layer coatings. A reverse stick-slip behavior was observed in the current system as compared to the normal stick-slip behavior found in the literature

  12. Characterization of damage created by alpha disintegrations in radionuclear waste glass

    International Nuclear Information System (INIS)

    Jacquet-Francillon, N.; Mueller, P.

    1990-01-01

    Study of thermostimulated luminescence of an alpha irradiated glass used as radionuclear waste glass has revealed the formation of a structural defect induced by alpha irradiation. To detect this structural modification the thermostimulated signal of an alpha irradiated sample is recorded under certain conditions. The nature of generated defects has been established using synthetic glasses of more simple composition such as silica or boro-silicate glasses. Results obtained with these simple glasses are transposed to alpha irradiated radionuclear waste glass. The problem is to see how autoirradiated glass could evolve in time. For this purpose actinide-doped glasses are now being fabricated and specific thermostimulated luminescence equipment has been developed for this purpose

  13. Operating experience during high-level waste vitrification at the West Valley Demonstration Project

    International Nuclear Information System (INIS)

    Valenti, P.J.; Elliott, D.I.

    1999-01-01

    This report provides a summary of operational experiences, component and system performance, and lessons learned associated with the operation of the Vitrification Facility (VF) at the West Valley Demonstration Project (WVDP). The VF was designed to convert stored high-level radioactive waste (HLW) into a stable waste form (borosilicate glass) suitable for disposal in a federal repository. Following successful completion on nonradioactive test, HLW processing began in July 1995. Completion of Phase 1 of HLW processing was reached on 10 June 1998 and represented the processing of 9.32 million curies of cesium-137 (Cs-137) and strontium-90 (Sr-90) to fill 211 canisters with over 436,000 kilograms of glass. With approximately 85% of the total estimated curie content removed from underground waste storage tanks during Phase 1, subsequent operations will focus on removal of tank heel wastes

  14. Detection of tetrahydrocannabinol residues on hands by ion-mobility spectrometry (IMS). Correlation of IMS data with saliva analysis.

    Science.gov (United States)

    Sonnberg, Saskia; Armenta, Sergio; Garrigues, Salvador; de la Guardia, Miguel

    2015-08-01

    Ion-mobility spectroscopy (IMS) was evaluated as a high-throughput, cheap, and efficient analytical tool for detecting residues of tetrahydrocannabinol (THC) on hands. Regarding the usefulness of hand residues as potential samples for determining THC handling and abuse, we studied the correlation between data obtained from cannabis consumers who were classified as positive after saliva analysis and from those who were classified as positive on the basis of the information from hand-residue analysis. Sampling consisted of wiping the hands with borosilicate glass microfiber filters and introducing these directly into the IMS after thermal desorption. The possibility of false positive responses, resulting from the presence of other compounds with a similar drift time to THC, was evaluated and minimised by applying the truncated negative second-derivative algorithm. The possibility of false negative responses, mainly caused by competitive ionisation resulting from nicotine, was also studied. Graphical abstract THC residues: from hands to analytical signals.

  15. Transuranic waste management program waste form development

    International Nuclear Information System (INIS)

    Bennett, W.S.; Crisler, L.R.

    1981-01-01

    To ensure that all technology necessary for long term management of transuranic (TRU) wastes is available, the Department of Energy has established the Transuranic Waste Management Program. A principal focus of the program is development of waste forms that can accommodate the very diverse TRU waste inventory and meet geologic isolation criteria. The TRU Program is following two approaches. First, decontamination processes are being developed to allow removal of sufficient surface contamination to permit management of some of the waste as low level waste. The other approach is to develop processes which will allow immobilization by encapsulation of the solids or incorporate head end processes which will make the solids compatible with more typical waste form processes. The assessment of available data indicates that dewatered concretes, synthetic basalts, and borosilicate glass waste forms appear to be viable candidates for immobilization of large fractions of the TRU waste inventory in a geologic repository

  16. Decontamination processes for waste glass canisters

    International Nuclear Information System (INIS)

    Rankin, W.N.

    1982-01-01

    A Defense Waste Processing Facility (DWPF) is currently being designed to convert Savannah River Plant liquid, high-level radioactive waste into a solid form, such as borosilicate glass. To prevent the spread of radioactivity, the outside of the canisters of waste glass must have very low levels of smearable radioactive contamination before they are removed from the DWPF. Several techniques were considered for canister decontamination: high-pressure water spray, electropolishing, chemical dissolution, and abrasive blasting. An abrasive blasting technique using a glass frit slurry has been selected for use in the DWPF. No additional equipment is needed to process waste generated from decontamination. Frit used as the abrasive will be mixed with the waste and fed to the glass melter. In contrast, chemical and electrochemical techniques require more space in the DWPF, and produce large amounts of contaminated by-products, which are difficult to immobilize by vitrification

  17. Atomic layer deposition of Al-doped ZnO thin films

    International Nuclear Information System (INIS)

    Tynell, Tommi; Yamauchi, Hisao; Karppinen, Maarit; Okazaki, Ryuji; Terasaki, Ichiro

    2013-01-01

    Atomic layer deposition has been used to fabricate thin films of aluminum-doped ZnO by depositing interspersed layers of ZnO and Al 2 O 3 on borosilicate glass substrates. The growth characteristics of the films have been investigated through x-ray diffraction, x-ray reflection, and x-ray fluorescence measurements, and the efficacy of the Al doping has been evaluated through optical reflectivity and Seebeck coefficient measurements. The Al doping is found to affect the carrier density of ZnO up to a nominal Al dopant content of 5 at. %. At nominal Al doping levels of 10 at. % and higher, the structure of the films is found to be strongly affected by the Al 2 O 3 phase and no further carrier doping of ZnO is observed.

  18. Measurements of acoustic properties for thin films

    International Nuclear Information System (INIS)

    Kushibiki, J.; Maehara, H.; Chubachi, N.

    1982-01-01

    A measurement method for determining thin-film acoustic properties, such as characteristic acoustic impedance, sound velocity, density, and stiffness constant, is developed with a simple measurement principle and high measurement accuracy. The acoustic properties are determined from a maximum reflection loss and a center frequency obtained through a frequency response of the reflection loss for an acoustic transmission line composed of a sapphire/film/water system by using the acoustic pulse mode measurement system in the UHF range. The determination of the acoustic properties is demonstrated for sputtered fused quartz film, low-expansion borosilicate glass films, and chalcogenide glass films of evaporated As 2 S 3 and As 2 Se 3 , within the measurement accuracy around 1--2%. It is also found that the acoustic properties of thin films are generally different from those of bulk materials, depending on the fabrication techniques and conditions

  19. Synthesis of novel ICIE16/BSG and ICIE16/BSG-NITRI bioglasses and description of ionic release kinetics upon immersion in SBF fluid: Effect of nitridation

    Science.gov (United States)

    Orgaz, Felipe; Amat, Daniel; Szycht, Olga; Dzika, Aleksandra; Barba, Flora; Becerra, José; Santos-Ruiz, Leonor

    2015-01-01

    A novel bioactive glass scaffold ICIE16/BSG has been prepared from a mixture of two different melt-derived glasses: a silicate bioglass (ICIE16) and a borosilicate bioglass (BSG). Combined processing techniques (gel casting and foam replication) were used to form three-dimensional, interconnected porous monolith scaffolds (Orgaz et al., 2016) [1]. They were then nitrided with a hot ammonia flow as described in (Aleixandre et al., 1973) [3] and (Nieto, 1984) [4] to synthesize the ICIE16/BSG-NITRI bioglass (Orgaz et al., 2016) [1]. Herein we present a flow chart summarizing the forming process, plus images of the resulting scaffold after sintering and drying. Bioactivity was characterized in vitro by immersion in simulated body fluid (SBF) for up to seven days. Data of ionic release kinetics upon SBF immersion are presented. PMID:26858981

  20. Initial demonstration of DWPF process and product control strategy using actual radioactive waste

    International Nuclear Information System (INIS)

    Andrews, M.K.; Bibler, N.E.; Jantzen, C.M.; Beam, D.C.

    1991-01-01

    The Defense Waste Processing Facility at the Savannah River Site (SRS) will vitrify high-level nuclear waste into borosilicate glass. The waste will be mixed with properly formulated glass-making frit and fed to a melter at 1150 degrees C. Process control and product quality are ensured by proper control of the melter feed composition. Algorithms have been developed to predict the processability of the melt and the durability of the final glass based on this feed composition. To test these algorithms, an actual radioactive waste contained in a shielded facility at SRS was analyzed and a frit composition formulated using a simple computer spreadsheet which contained the algorithms. This frit was then mixed with the waste and the resulting slurry fed to a research scale joule-heated melter operated remotely. Approximately 24 kg of glass were successfully prepared. This paper will describe the frit formulation, the vitrification process, and the glass durability

  1. Devitrification of defense nuclear waste glasses: role of melt insolubles

    International Nuclear Information System (INIS)

    Bickford, D.F.; Jantzen, C.M.

    1985-01-01

    Time-temperature-transformation (TTT) curves have been determined for simulated nuclear waste glasses bounding the compositional range in the Defense Waste Processing Facility (DWPF). Formulations include all of the minor chemical elements such as ruthenium and chromium which have limited solubility in borosilicate glasses. Heterogeneous nucleation of spinel on ruthenium dioxide, and subsequent nucleation of acmite on spinel is the major devitrification path. Heterogeneous nucleation on melt insolubles causes more rapid growth of crystalline devitrification phases, than in glass free of melt insolubles. These studies point out the importance of simulating waste glass composition and processing as accurately as possible to obtain reliable estimates of glass performance. 11 refs., 8 figs., 1 tab

  2. An update on the quality assurance for the waste vitrification plants

    Energy Technology Data Exchange (ETDEWEB)

    Caplinger, W.H.; Shugars, D.L.; Carlson, M.K.

    1990-01-01

    Immobilization of high-level defense production wastes is an important step in environmental restoration. The best available technology for immobilization of this waste currently is by incorporation into borosilicate glass, i.e., vitrification. Three US sites are active in the design, construction, or operation of vitrification facilities. The status, facility description and Quality Assurance (QA) development for each facility was presented at the 1989 Energy Division Conference. This paper presents the developments since that time. The West Valley Demonstration Project (WVDP) in northwestern New York State has demonstrated the technology. At the Savannah River Site (SRS) in South Carolina the Defense Waste Processing Facility (DWPF) has completed design, construction is essentially complete, and preparation for operation is underway. The Hanford Waste Vitrification Plant (HWVP) in Washington State is in initial Detailed Design. 4 refs.

  3. Study of neutron absorbing microspheres in research reactors - Neutronic analyse

    International Nuclear Information System (INIS)

    Gana Watkins, Ignacio A.; Prado, Miguel O.; Mazufri, Claudio; Tunon, Juan M

    2012-01-01

    Now-a-days, it is increasingly common for nuclear power plants, as well as research reactors, to be designed and built with an alternative safety system aside from control rods. The acids and/or salts in solution injection systems is most frequently used. However, these systems present several implementation and operation problems due to the physical and chemical properties of the used compounds. After analyzing these drawbacks, we developed a new alternative safety system that contains the absorbing element isolated from the aqueous medium. In this context, it's proposed the use of aluminum borosilicate microspheres. The current paper presents erosion wear experiments to determine under which conditions microspheres can be considered as a potential component of a secondary shut down system in a nuclear facility (author)

  4. High rate operation of micro-strip gas chambers on diamond-coated glass

    CERN Document Server

    Bouclier, Roger; Million, Gilbert; Ropelewski, Leszek; Sauli, Fabio; Temmel, T; Cooke, R A; Donnel, S; Sastri, S A; Sonderer, N

    1996-01-01

    Very high rate operation of micro­strip gas chambers can be achieved using slightly conducting substrates. We describe preliminary measurements realized with detectors manufactured on boro-silicate glass coated, before the photo-lithographic processing, with a diamond layer having a surface resistivity of around 1014 ‡/o. Stable medium-term operation, and a rate capability largely exceeding the one obtained with identical plates manufactured on uncoated glass are demonstrated. If these results are confirmed by long-term measurements the diamond coating technology appears very attractive since it allows, with a moderate cost overhead, to use thin, commercially available glass with the required surface quality for the large-scale production of gas micro-strip detectors.

  5. Inorganic Corrosion-Inhibitive Pigments for High-Temperature Alkali-activated Well Casing Foam Cement

    Energy Technology Data Exchange (ETDEWEB)

    Sugama, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pyatina, T. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-11-01

    This study evaluates inorganic pigments for improving carbon steel (CS) brine-corrosion protection by the sodium metasilicate-activated calcium aluminate cement/Fly Ash blend at 300°C. Calcium borosilicate (CBS) and zinc phosphate, significantly improved CS corrosion-protection by decreasing cement’s permeability for corrosive ions and inhibiting anodic corrosion. An amorphous Na2O-Al2O3-SiO2-H2O phase tightly attached to CS surface formed at 300oC in CBS-modified cement pore solution. The corrosion rate of the CS covered with this phase was nearly 4-fold lower than in the case of nonmodified cement pore solution where the major phase formed on the surface of CS was crystalline analcime.

  6. Inorganic Corrosion-Inhibitive Pigments for High-Temperature Alkali-activated Well Casing Foam Cement

    Energy Technology Data Exchange (ETDEWEB)

    Sugama, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pyatina, T. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-11-14

    This study evaluates inorganic pigments for improving carbon steel (CS) brine-corrosion protection by the sodium metasilicate-activated calcium aluminate cement/Fly Ash blend at 300°C. Calcium borosilicate (CBS) and zinc phosphate, significantly improved CS corrosion-protection by decreasing cement’s permeability for corrosive ions and inhibiting anodic corrosion. An amorphous Na2O-Al2O3-SiO2-H2O phase tightly attached to CS surface formed at 300oC in CBS-modified cement pore solution. The corrosion rate of the CS covered with this phase was nearly 4-fold lower than in the case of nonmodified cement pore solution where the major phase formed on the surface of CS was crystalline analcime.

  7. The DWPF strategy for producing an acceptable product

    International Nuclear Information System (INIS)

    Goldston, W.T.; Plodinec, M.J.

    1991-01-01

    The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) will convert the 130 million liters of high-level nuclear waste at SRS into stable borosilicate glass. Production of canistered waste forms by the DWPF is scheduled to begin well before submission of the license application for the first repository. The Department of Energy has defined waste acceptance specifications to ensure that DWPF canistered waste forms will be acceptable for eventual disposal. To ensure that canistered waste forms meet those specifications, a program is being carried out to qualify the waste form and those aspects of the production process which affect product quality. This program includes: Pre-production qualification testing of simulated and actual waste forms; Disciplined demonstrations of the ability to produce an acceptable product during startup testing; and Application of a rigorous product control program during production

  8. NMR Studies of Permanent Compression in Oxide Glasses

    DEFF Research Database (Denmark)

    Youngman, Randall E.; Svenson, Mouritz Nolsøe; Mauro, John C.

    useful tool for examining these changes in network structure, especially for boron-containing glasses, which are particularly sensitive to permanent compression. Here we describe studies based on hot isostatic compression of several different borate and borosilicate glasses, where changes in short......Pressure-induced structural rearrangement in oxide glasses is manifested by modification of both short- and intermediate-range structures, including changes to the local coordination numbers of network forming cations and alteration of the modifier environment. NMR spectroscopy is an especially...... of the network modifying sodium atoms, will be discussed. Such changes in network structure aid in understanding the pressure-induced properties of these glasses, such as density, elastic moduli, hardness and crack resistance....

  9. Interaction of groundwater and fresh basalt fissure surfaces and its effect on the migration of actinides

    International Nuclear Information System (INIS)

    Vandegrift, G.F.; Bowers, D.L.; Gerding, T.J.; Fried, S.M.; Wilbur, C.K.; Seitz, M.G.

    1983-01-01

    Experiments are being performed at Argonne National Laboratory (ANL): (1) to identify interactions of radionuclides and repository components that effect nuclide migration, and (2) to assess changes in nuclide migration caused by modifications expected upon aging of the waste, clay backfill, and rock. The experiments are conducted with radioactive borosilicate glass, bentonite and mechanically fissured basalt rock in flowing water analogous to their configuration in a breach of a nuclear waste repository. Changes undergone by the groundwater as it passed through the fissure include: (1) drop in pH from 10 to 8, (2) loss of suspended particulate, and (3) loss of dissolved/suspended U, Np, and Pu. These effects, also studied as functions of radiation dose and of laboratory aging of the repository components, are related to the predicted long-term performance of a nuclear waste repository

  10. Operating experience during high-level waste vitrification at the West Valley Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Valenti, P.J.; Elliott, D.I.

    1999-01-01

    This report provides a summary of operational experiences, component and system performance, and lessons learned associated with the operation of the Vitrification Facility (VF) at the West Valley Demonstration Project (WVDP). The VF was designed to convert stored high-level radioactive waste (HLW) into a stable waste form (borosilicate glass) suitable for disposal in a federal repository. Following successful completion on nonradioactive test, HLW processing began in July 1995. Completion of Phase 1 of HLW processing was reached on 10 June 1998 and represented the processing of 9.32 million curies of cesium-137 (Cs-137) and strontium-90 (Sr-90) to fill 211 canisters with over 436,000 kilograms of glass. With approximately 85% of the total estimated curie content removed from underground waste storage tanks during Phase 1, subsequent operations will focus on removal of tank heel wastes.

  11. Measurements of recombination coefficient of hydrogen atoms on plasma deposited thin films

    International Nuclear Information System (INIS)

    Drenik, A.; Vesel, A.; Mozetic, M.

    2006-01-01

    We have performed experiments in plasma afterglow in order to determine the recombination coefficients of plasma deposited thin films of tungsten and graphite. Plasma deposited films rather than bulk material were used in order to more closely emulate surface structure of plasma-facing material deposits in fusion reactors. We have also determined the recombination coefficient of 85250 borosilicate glass and Teflon. Plasma was created by means of a radio frequency generator in a mixture of argon and hydrogen at the pressures between 60 Pa and 280 Pa. The degree of dissociation of hydrogen molecules was found to be between 0.1 and 1. The H-atom density was measured by Fiber Optic Catalytic Probe. The recombination coefficient was determined by measuring the axial profile of the H-atom density and using Smith's side arm diffusion model. (author)

  12. Canonical correlation of waste glass compositions and durability, including pH

    Energy Technology Data Exchange (ETDEWEB)

    Oeksoy, D.; Pye, L.D. (Alfred Univ., NY (United States)); Bickford, D.F.; Ramsey, W.G. (Westinghouse Savannah River Co., Aiken, SC (United States))

    1993-01-01

    Control of waste glass durability is a major concern in the immobilization of radioactive and mixed wastes. Leaching rate in standardized laboratory tests is being used as a demonstration of consistency of the response of waste glasses in the final disposal environment. The leaching of silicate and borosilicate glasses containing alkali or alkaline earth elements is known to be autocatalytic, in that the initial ion exchange of alkali in the glass for hydrogen ions in water results in the formation of OH and increases the pH of the leachate. The increased pH then increases the rate of silicate network attack, accelerating the leaching effect. In well formulated glasses this effect reaches a thermodynamic equilibrium when leachate saturation of a critical species, such as silica, or a dynamic equilibrium is reached when the pH shift caused by incremental leaching has negligible effect on pH. This report analyzes results of a seven leach test on waste glasses.

  13. Canonical correlation of waste glass compositions and durability, including pH

    Energy Technology Data Exchange (ETDEWEB)

    Oeksoy, D.; Pye, L.D. [Alfred Univ., NY (United States); Bickford, D.F.; Ramsey, W.G. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1993-05-01

    Control of waste glass durability is a major concern in the immobilization of radioactive and mixed wastes. Leaching rate in standardized laboratory tests is being used as a demonstration of consistency of the response of waste glasses in the final disposal environment. The leaching of silicate and borosilicate glasses containing alkali or alkaline earth elements is known to be autocatalytic, in that the initial ion exchange of alkali in the glass for hydrogen ions in water results in the formation of OH and increases the pH of the leachate. The increased pH then increases the rate of silicate network attack, accelerating the leaching effect. In well formulated glasses this effect reaches a thermodynamic equilibrium when leachate saturation of a critical species, such as silica, or a dynamic equilibrium is reached when the pH shift caused by incremental leaching has negligible effect on pH. This report analyzes results of a seven leach test on waste glasses.

  14. Shielded Canister Transporter

    International Nuclear Information System (INIS)

    Eidem, G.G. Jr.; Fages, R.

    1993-01-01

    The Hanford Waste Vitrification Plant (HWVP) will produce canisters filled with high-level radioactive waste immobilized in borosilicate glass. This report discusses a Shielded Canister Transporter (SCT) which will provide the means for safe transportation and handling of the canisters from the Vitrification Building to the Canister Storage Building (CSB). The stainless steel canisters are 0.61 meters in diameter, 3.0 meters tall, and weigh approximately 2,135 kilograms, with a maximum exterior surface dose rate of 90,000 R/hr. The canisters are placed into storage tubes to a maximum of three tall (two for overpack canisters) with an impact limiter placed at the tube bottom and between each canister. A floor plug seals the top of the storage tube at the operating floor level of the CSB

  15. Hydrogen production with a solar steam–methanol reformer and colloid nanocatalyst

    KAUST Repository

    Lee, Ming-Tsang

    2010-01-01

    In the present study a small steam-methanol reformer with a colloid nanocatalyst is utilized to produce hydrogen. Radiation from a focused continuous green light laser (514 nm wavelength) is used to provide the energy for steam-methanol reforming. Nanocatalyst particles, fabricated by using pulsed laser ablation technology, result in a highly active catalyst with high surface to volume ratio. A small novel reformer fabricated with a borosilicate capillary is employed to increase the local temperature of the reformer and thereby increase hydrogen production. The hydrogen production output efficiency is determined and a value of 5% is achieved. Experiments using concentrated solar simulator light as the radiation source are also carried out. The results show that hydrogen production by solar steam-methanol colloid nanocatalyst reforming is both feasible and promising. © 2009 Professor T. Nejat Veziroglu.

  16. Joining of SiCf/SiC composites for thermonuclear fusion reactors

    International Nuclear Information System (INIS)

    Ferraris, M.; Badini, C.; Montorsi, M.; Appendino, P.; Scholz, H.W.

    1994-01-01

    Due to their favourable radiological behaviour, SiC f /SiC composites are promising structural materials for future use in fusion reactors. A problem to cope with is the joining of the ceramic composite material (CMC) to itself for more complex structures. Maintenance concepts for a reactor made of SiC f /SiC will demand a method of joining. The joining agents should comply with the low-activation approach of the base material. With the acceptable elements Si and Mg, sandwich structures of composite/metal/composite were prepared in Ar atmosphere at temperatures just above the melting points of the metals. Another promising route is the use of joining agents of boro-silicate glasses: their composition can be tailored to obtain softening temperatures of interest for fusion applications. The glassy joint can be easily ceramised to improve thermomechanical properties. The joining interfaces were investigated by SEM-EDS, XRD and mechanical tests. ((orig.))

  17. Preliminary assessment of blending Hanford tank wastes

    Energy Technology Data Exchange (ETDEWEB)

    Geeting, J.G.H.; Kurath, D.E.

    1993-03-01

    A parametric study of blending Hanford tank wastes identified possible benefits from blending wastes prior to immobilization as a high level or low level waste form. Track Radioactive Components data were used as the basis for the single-shell tank (SST) waste composition, while analytical data were used for the double-shell tank (DST) composition. Limiting components were determined using the existing feed criteria for the Hanford Waste Vitrification Plant (HWVP) and the Grout Treatment Facility (GTF). Results have shown that blending can significantly increase waste loading and that the baseline quantities of immobilized waste projected for the sludge-wash pretreatment case may have been drastically underestimated, because critical components were not considered. Alternatively, the results suggest further review of the grout feed specifications and the solubility of minor components in HWVP borosilicate glass. Future immobilized waste estimates might be decreased substantially upon a thorough review of the appropriate feed specifications.

  18. Iron Phosphate Glasses: An Alternative for Vitrifying Certain Nuclear Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Delbert E. Day; Chandra S. Ray; Cheol-Woon Kim

    2004-12-28

    Vitrification of nuclear waste in a glass is currently the preferred process for waste disposal. DOE currently approves only borosilicate (BS) type glasses for such purposes. However, many nuclear wastes, presently awaiting disposal, have complex and diverse chemical compositions, and often contain components that are poorly soluble or chemically incompatible in BS glasses. Such problematic wastes can be pre-processed and/or diluted to compensate for their incompatibility with a BS glass matrix, but both of these solutions increases the wasteform volume and the overall cost for vitrification. Direct vitrification using alternative glasses that utilize the major components already present in the waste is preferable, since it avoids pre-treating or diluting the waste, and, thus, minimizes the wasteform volume and overall cost.

  19. The behavior of silicon and boron in the surface of corroded nuclear waste glasses: an EFTEM study

    International Nuclear Information System (INIS)

    Buck, E. C.; Smith, K. L.; Blackford, M. G.

    1999-01-01

    Using electron energy-loss filtered transmission electron microscopy (EFTEM), we have observed the formation of silicon-rich zones on the corroded surface of a West Valley (WV6) glass. This layer is approximately 100-200 nm thick and is directly underneath a precipitated smectite clay layer. Under conventional (C)TEM illumination, this layer is invisible; indeed, more commonly used analytical techniques, such as x-ray energy dispersive spectroscopy (EDS), have failed to describe fully the localized changes in the boron and silicon contents across this region. Similar silicon-rich and boron-depleted zones were not found on corroded Savannah River Laboratory (SRL) borosilicate glasses, including SRL-EA and SRL-51, although they possessed similar-looking clay layers. This study demonstrates a new tool for examining the corroded surfaces of materials

  20. Palmtop EPMA by electric battery

    International Nuclear Information System (INIS)

    Imashuku, Susumu; Imanishi, Akira; Kawai, Jun

    2012-01-01

    The measurement pressure of a palmtop electron probe X-ray microanalyzer (EPMA) we previously reported was reduced using stainless steel vacuum flanges for the chamber instead of a borosilicate glass tube. The improved palmtop EPMA could reach the measurement pressure of 1 Pa in 5 minutes. The time was more than twice shorter than that to reach the measurement pressure of 5 Pa with the palmtop EPMA we previously reported. Titanium, copper K lines and silver Lα line were observed during 90 seconds measurement in addition to chromium, iron, and nickel K lines when titanium, copper, and silver plates were placed on the carbon sample stage. Chromium, iron, and nickel K lines came from stainless steel, and copper K lines came from copper rod and copper plate placed on the sample stage. The improved palmtop EPMA can analyze metals except for chromium, iron, nickel, and small amount of copper in 90 seconds.

  1. Kinetic and thermodynamic controls on silica reactivity: an analog for waste disposal media

    International Nuclear Information System (INIS)

    Dove, P.M.; Icenhower, J.

    1997-01-01

    Silicate glasses are currently being proposed as the disposal media for radioactive and other toxic wastes. The dissolution behaviour of borosilicate glass is incompletely understood. One approach is to simplify the chemistry and first develop a better understanding of vitreous silica (v-SiO 2 ) as a simple analog of waste glass. This article reviews all the knowledge that is known about the dissolution of silica. Studies quantifying the effects of temperature, solution pH, and single salts on dissolution rates of quartz suggest that pH and cation-dependent dissolution trends hold for all of the silica polymorphs. The purpose of this review is to develop a consistent picture of glass reactivity by understanding how the molecular arrangement of constituents within glass, beginning with the Si-O bond, affects the dissolution processes. (A.C.)

  2. Intracellular ZnO Nanorods Conjugated with Protoporphyrin for Local Mediated Photochemistry and Efficient Treatment of Single Cancer Cell

    Science.gov (United States)

    Kishwar, S.; Asif, M. H.; Nur, O.; Willander, M.; Larsson, Per-Olof

    2010-10-01

    ZnO nanorods (NRs) with high surface area to volume ratio and biocompatibility is used as an efficient photosensitizer carrier system and at the same time providing intrinsic white light needed to achieve cancer cell necrosis. In this letter, ZnO nanorods used for the treatment of breast cancer cell (T47D) are presented. To adjust the sample for intracellular experiments, we have grown the ZnO nanorods on the tip of borosilicate glass capillaries (0.5 μm diameter) by aqueous chemical growth technique. The grown ZnO nanorods were conjugated using protoporphyrin dimethyl ester (PPDME), which absorbs the light emitted by the ZnO nanorods. Mechanism of cytotoxicity appears to involve the generation of singlet oxygen inside the cell. The novel findings of cell-localized toxicity indicate a potential application of PPDME-conjugated ZnO NRs in the necrosis of breast cancer cell within few minutes.

  3. High-temperature glasses for nuclear waste isolation

    Energy Technology Data Exchange (ETDEWEB)

    Bunnell, L.R.; Maupin, G.D.; Oma, K.H.

    1986-03-01

    As part of the effort to discover and evaluate viable second-generation waste forms, glasses with processing temperatures higher than the 1100 to 1200/sup 0/C used for reference borosilicate glasses are being examined. This approach allows the use of previously developed technology for producing nuclear waste glasses, with a few modifications. Low alkali high alumina-boron glasses processed at 1400/sup 0/C and containing 25 wt % simulated reprocessed commercial nuclear waste have been fabricated and evaluated for chemical durability. These glasses exhibited matrix dissolution rates at 90/sup 0/C in deionized water that are at least an order of magnitude lower than current reference glass compositions over a wide range of flow conditions. 6 refs., 5 figs.

  4. Status of high level and alpha bearing waste management in PNC

    International Nuclear Information System (INIS)

    Uematsu, Kunihiko

    1982-04-01

    For completing the nuclear fuel cycle in Japan, Power Reactor and Nuclear Fuel Development Corporation (PNC) has a role to promote the management of high level and alpha bearing wastes. For high level waste management, it is planned in Japan to initiate the operation of a vitrification pilot plant by 1987 for the development of the solidification process, and to make it possible to initiate trial disposal by 2015 for the development of geological disposal technology. In PNC, monolithic borosilicate glass was selected as the final form of solidification. Alpha bearing wastes have been produced in the mixed oxide fuel fabrication facility and the reprocessing plant in PNC; and the amount should increase considerably in the future in Japan. About these two areas of waste management, the policy and the research/development programs are described. (J.P.N.)

  5. Radiant energy dissipation during final storage of high-level radioactive waste in rock salt

    International Nuclear Information System (INIS)

    Ramthun, H.

    1981-08-01

    A final disposal concept is assumed where the high-active waste from 1400 t of uranium, remaining after conditioning, is solidified in borosilicate glass and distributed in 1.760 waste casks. These containers 1.2 m in height and 0.3 m in diameter are to be buried 10 years after the fuel is removed from the reactor in the 300 m deep boreholes of a salt dome. For this design the mean absorbed dose rates are calculated in the glass die (3.9 Gy/s), the steel mantle (0.26 Gy/s) and in the salt rock (0.12 Gy/s at a distance of 1 cm and 0.034 Gy/s at a distance of 9 cm from the container surface) valid at the beginning of disposal. The risk involved with these amounts of stored lattice energy is shortly discussed. (orig.) [de

  6. RETENTION OF SULFATE IN HIGH LEVEL RADIOACTIVE WASTE GLASS

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K.

    2010-09-07

    High level radioactive wastes are being vitrified at the Savannah River Site for long term disposal. Many of the wastes contain sulfate at concentrations that can be difficult to retain in borosilicate glass. This study involves efforts to optimize the composition of a glass frit for combination with the waste to improve sulfate retention while meeting other process and product performance constraints. The fabrication and characterization of several series of simulated waste glasses are described. The experiments are detailed chronologically, to provide insight into part of the engineering studies used in developing frit compositions for an operating high level waste vitrification facility. The results lead to the recommendation of a specific frit composition and a concentration limit for sulfate in the glass for the next batch of sludge to be processed at Savannah River.

  7. A study on the direct use of spent PWR fuel in CANDU -A study on the radioactive waste management for DUPIC fuel cycle-

    International Nuclear Information System (INIS)

    Park, Hyun Soo; Jun, Kwan Sik; Nah, Jung Won; Park, Jang Jin; Kim, Jong Hoh; Cho, Yung Hyun; Baek, Seung Woo; Shin, Jin Myung; Yang, Seung Yung

    1994-07-01

    The immobilization materials for radioactive wastes resulting from the DUPIC fuel manufacturing process were selected and their characteristics were evaluated. To predict the trapping behavior of the Ruthenium, a semi-volatile nuclide, its volatility was measured and thermogravimetric analysis were performed with simulated fuel. New Ruthenium trapping material was developed which is deposited on ceramic honey-comb monolith of cordierite. The base glass was manufactured with fly ash added to the borosilicate glass. The composition of the scrap waste was calculated based on the PWR spent fuel which has initial 235 U content of 3.5%, burnup of 35,000 MWD/MTU and cooling time of 10 years. Simulated waste glass was manufactured, and its chemical durability was evaluated by soxhlet leach test. Radioactivity of non-oxidized cladding material were measured. The preliminary design criteria were prepared for off-gas treatment system in IMEF. 31 figs, 42 tabs, 51 refs. (Author)

  8. Composition and redox control of waste glasses: Recommendation for process control limit

    International Nuclear Information System (INIS)

    Jantzen, C.M.; Plodinec, M.J.

    1986-01-01

    An electrochemical series of redox couples, originally developed for Savannah River Laboratory glass frit 131 (SRL-131) as a reference composition, has been extended to two other alkali borosilicate compositions that are candidate glasses for nuclear waste immobilization. Since no dramatic differences were ascertained in the redox chemistry of selected multivalent elements in SRL-131 versus that in Savannah River Laboratory glass frit 165 (SRL-165) and in West Valley glass number-sign 205 (WV-205), the comprehensive electrochemical series can readily be applied to a range of nuclear waste glass compositions. In order to alleviate potential problems with foaming and precipitation of insolubles during the processing of the nuclear waste in these glass melts, the [Fe 2+ ]/[Fe 3+ ] ratio of the melt should be between 0.1 and 0.5. 27 refs., 4 figs., 2 tabs

  9. Design and construction innovations of the Defense Waste Processing Facility

    International Nuclear Information System (INIS)

    McKibben, J.M.; Pair, C.R.; Bethmann, H.K.

    1990-01-01

    Construction of the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) is essentially complete. The facility is designed to convert high level radioactive waste, now contained in large steel tanks as aqueous salts and sludge, into borosilicate glass which will solidify in stainless steel canisters. All processing of the radioactive material and operations in a radioactive environment will be done remotely. The stringent requirements dictated by remote operation and new approaches to the glassification process led to the development of a number of first-of-a-kind pieces of equipment, new construction fabrication and erection techniques, and new applications of old techniques. The design features and construction methods used in the vitrification building and its equipment were to accomplish the objective of providing a state-of-the-art vitrification facility. 3 refs., 10 figs

  10. Impact of alpha-recoil damage on dissolution of thoriated glass

    International Nuclear Information System (INIS)

    Eyal, Y.; Ewing, R.C.

    1993-01-01

    Reaction of a seventeen-year old borosilicate glass containing 4 wt% ThO 2 with a bicarbonate-carbonate solution was investigated for times from a few minutes up to approximately one year. For the untreated glass, the initial 228-Th leach rate was enhanced relative to the initial 232-Th leach rate by 15--45%. This incongruent dissolution occurs due to the selective removal of radiogenic 228-Th nuclides from 228-Ra-recoil tracks, damaged regions in the aperiodic glass. Heating the glass at 650 C in air prior to leaching eliminates the 228-Th/232-Th fractionation. Similar enhanced dissolution of alpha-decay products may occur in nuclear waste glasses/groundwater systems; thus, actinide-containing glasses should be examined for alpha-recoil damage effects in order to insure satisfactory prediction of the long-term release of actinides from the nuclear waste glass

  11. Deposition of vanadium oxide films by direct-current magnetron reactive sputtering

    Science.gov (United States)

    Kusano, E.; Theil, J. A.; Thornton, John A.

    1988-01-01

    It is demonstrated here that thin films of vanadium oxide can be deposited at modest substrate temperatures by dc reactive sputtering from a vanadium target in an O2-Ar working gas using a planar magnetron source. Resistivity ratios of about 5000 are found between a semiconductor phase with a resistivity of about 5 Ohm cm and a metallic phase with a resistivity of about 0.001 Ohm cm for films deposited onto borosilicate glass substrates at about 400 C. X-ray diffraction shows the films to be single-phase VO2 with a monoclinic structure. The VO2 films are obtained for a narrow range of O2 injection rates which correspond to conditions where cathode poisoning is just starting to occur.

  12. Spectral properties of americium(III) in silicate matrices. Concentration-dependent up-conversion emission

    International Nuclear Information System (INIS)

    Assefa, Zerihun; Haire, R.G.; Stump, N.

    2002-01-01

    We have been pursuing the spectroscopic properties of actinide ions in silicate matrices. One facet of these studies involves the behavior of Stokes and anti-Stokes emissions exhibited by Am 3+ in these hosts. Several attributes have been found to influence the spectral profile, which include excitation wavelength, laser power, and dopant-concentration. Excitation with the 514.5 nm (19435 cm -1 ) line of argon laser provides anti-Stokes emissions at 21100 and ∼19920 cm -1 in the borosilicate matrices. This up-conversion was found to proceed through a multi-photon scheme, and the efficiency increases with increased dopant concentration. Based on our concentration-dependent studies, the up-conversion is suggested to involve a cross-relaxation process [( 5 D 1' , 7 F 0' ) ( 7 F 6' , 7 F 2' )] between neighboring americium ions. (author)

  13. Time-Temperature-Transformation Study of Simulated Hanford Tank Waste (AZ-101) and Optimization of Glass Formulation for Processing Such Waste

    Energy Technology Data Exchange (ETDEWEB)

    Ramsey, W. G.; Kauffman, B. M.; Bricka, M.; Meaker, T. F.; Giordana, A.; Smith, J. D.; Miller, F. S.; Bohannan, E.; Powell, J.; Reich, M.; Jordan, J.; Venter, L.; Barletta, R. E.; Ramsey, A. A.; Maise, G. M.; Manowitz, B.; Steinberg, M.; Salzano, F.

    2003-02-26

    This paper presents the current results of a study for the optimization of the quality of the wasteform to be produced by vitrification of Hanford High Level Waste (HLW). A simulant of the content of Hanford Tank AZ-101 has been used for the experiments. A first phase of the research focused on the wasteform composition and showed that a high quality and chemical-resistant wasteform can be formed incorporating 60 weight % of dried waste into a borosilicate glass enriched with zinc oxide and boric acid and provided some indication about the heat treatment of the melt. A second phase of the study, still in progress, refines these findings. A detailed crystallinity survey of the waste form after various heat treatments has been performed, culminating in the development of a time-temperature-transformation (TTT) diagram. The results of the first phase of research and preliminary results from the second phase are described.

  14. Synthesis of nanoscale copper nitride thin film and modification of the surface under high electronic excitation.

    Science.gov (United States)

    Ghosh, S; Tripathi, A; Ganesan, V; Avasthi, D K

    2008-05-01

    Nanoscale (approximately 90 nm) Copper nitride (Cu3N) films are deposited on borosilicate glass and Si substrates by RF sputtering technique in the reactive environment of nitrogen gas. These films are irradiated with 200 MeV Au15+ ions from Pelletron accelerator in order to modify the surface by high electronic energy deposition of heavy ions. Due to irradiation (i) at incident ion fluence of 1 x 10(12) ions/cm2 enhancement of grains, (ii) at 5 x 10912) ions/cm2 mass transport on the films surface, (iii) at 2 x 10(13) ions/cm2 line-like features on Cu3N/glass and nanometallic structures on Cu3N/Si surface are observed. The surface morphology is examined by atomic force microscope (AFM). All results are explained on the basis of a thermal spike model of ion-solid interaction.

  15. Processing glass-pyrochlore composites for nuclear waste encapsulation

    International Nuclear Information System (INIS)

    Pace, S.; Cannillo, V.; Wu, J.; Boccaccini, D.N.; Seglem, S.; Boccaccini, A.R.

    2005-01-01

    Glass matrix composites have been developed as alternative materials to immobilize nuclear solid waste, in particular actinides. These composites are made of soda borosilicate glass matrix, into which particles of lanthanum zirconate pyrochlore are encapsulated in concentrations of 30 vol.%. The fabrication process involves powder mixing followed by hot-pressing. At the relatively low processing temperature used (620 deg. C), the pyrochlore crystalline structure of the zirconate, which is relevant for containment of radioactive nuclei, remains unaltered. The microstructure of the composites exhibits a homogeneous distribution of isolated pyrochlore particles in the glass matrix and strong bonding at the matrix-particle interfaces. Hot-pressing was found to lead to high densification (95% th.d.) of the composite. The materials are characterized by relatively high elastic modulus, flexural strength, hardness and fracture toughness. A numerical approach using a microstructure-based finite element solver was used in order to investigate the mechanical properties of the composites

  16. Powder technological vitrification of simulated high-level waste

    International Nuclear Information System (INIS)

    Gahlert, S.

    1988-03-01

    High-level waste simulate from the reprocessing of light water reactor and fast breeder fuel was vitrified by powder technology. After denitration with formaldehyde, the simulated HLW is mixed with glass frit and simultaneously dried in an oil-heated mixer. After 'in-can calcination' for at least 24 hours at 850 or 950 K (depending on the type of waste and glass), the mixture is hot-pressed in-can for several hours at 920 or 1020 K respectively, at pressures between 0.4 and 1.0 MPa. The technology has been demonstrated inactively up to diameters of 30 cm. Leach resistance is significantly enhanced when compared to common borosilicate glasses by the utilization of glasses with higher silicon and aluminium content and lower sodium content. (orig.) [de

  17. Output Properties of Transparent Submount Packaged FlipChip Light-Emitting Diode Modules

    Directory of Open Access Journals (Sweden)

    Preetpal Singh

    2016-06-01

    Full Text Available Flip chip technology has been widely adopted in modern power light-emitting diode (LED fabrications and its output efficiency is closely related to the submount material properties. Here, we present the electrical, optical and thermal properties of flip chip light-emitting diodes mounted on transparent sapphire and borosilicate glass which have shown a higher output luminous flux when compared to the traditional non-transparent mounted LEDs. Exhibiting both better thermal conductivity and good optical transparency, flip chip LEDs with a sapphire submount showed superior performance when compared to the non-transparent silicon submount ones, and also showed better optical performance than the flip chip LEDs mounted on transparent but poor-thermal-conducting glass substrates. The correspondent analysis was carried out using ANSYS 14 to compare the experimental thermal imaging with the simulation results. TracePro software was also used to check the output luminous flux dependency on different LED mounting designs.

  18. Experimental study of the hydrothermal alteration of a chemical analogue of the French nuclear glass in a thermal gradient: characterization of newly formed phases and of matter transfers

    International Nuclear Information System (INIS)

    Poinssot, Christophe

    1994-01-01

    As the most dangerous radioactive wastes are to be stored in deep geological layers after having been packaged in barrels made of borosilicate glasses, this research report addresses the study of the alteration of such glasses through the study of a chemical analogue. In order to experimentally model phenomena involved within a storage, the studied glass has been submitted to different thermal gradients between 320 and 150 C and during 3 to 5 months. These gradients comply with those met about the parcels, and allows the spatial evolution of the waste parcel at a given moment, as well as the evolution in time (progressive cooling of wastes) to be simultaneously simulated. The different phases formed within the gradient have been studied and characterized by scanning electronic microscopy, semi-quantitative microanalysis, and X-ray micro-diffraction [fr

  19. Evaluation and selection of candidate high-level waste forms

    International Nuclear Information System (INIS)

    1982-03-01

    Seven candidate waste forms being developed under the direction of the Department of Energy's National High-Level Waste (HLW) Technology Program, were evaluated as potential media for the immobilization and geologic disposal of high-level nuclear wastes. The evaluation combined preliminary waste form evaluations conducted at DOE defense waste-sites and independent laboratories, peer review assessments, a product performance evaluation, and a processability analysis. Based on the combined results of these four inputs, two of the seven forms, borosilicate glass and a titanate based ceramic, SYNROC, were selected as the reference and alternative forms for continued development and evaluation in the National HLW Program. Both the glass and ceramic forms are viable candidates for use at each of the DOE defense waste-sites; they are also potential candidates for immobilization of commercial reprocessing wastes. This report describes the waste form screening process, and discusses each of the four major inputs considered in the selection of the two forms

  20. Fiscal Year 2010 Summary Report on the Epsilon-Metal Phase as a Waste Form for 99 Tc

    Energy Technology Data Exchange (ETDEWEB)

    Strachan, Denis M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Crum, Jarrod V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Riley, Brian J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zumhoff, Mac R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2010-09-30

    Epsilon metal (ε-metal) is generated in nuclear fuel during irradiation. This metal consists of Pd, Ru, Rh, Mo, and some Te. These accumulate at the UO2 grain boundaries as small (ca 5 µm) particles. These metals have limited solubility in the acid used to dissolve fuel during reprocessing and in typical borosilicate glass. These must be treated separately to improve overall waste loading in glass. This low solubility and their survival in 2 Gy-old natural reactors led us to investigate them as a waste form for the immobilization of 99Tc and 107Pd, two very long-lived isotopes.