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Sample records for sodium sulphate glasses

  1. 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)

  2. Sulphate decomposition and sodium oxide activity in soda-lime-silica glass metls

    NARCIS (Netherlands)

    Beerkens, R.G.C.

    2003-01-01

    Reaction equilibrium constants for the sulfate decomposition process, which releases oxygen and sulfur oxide gas in sodalimesilica glass melts, have been determined. The chemical solubility of SO2, probably in the form of sulfite ions in sodalimesilica melts, has also been determined. The chemical

  3. 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)

  4. 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)

  5. Structure of sodium alkyl sulphate micelles

    International Nuclear Information System (INIS)

    Vass, Sz.

    1990-05-01

    Micellar aggregation numbers of aggregated sodium octyl, decyl, dodecyl and tetradecyl sulphate molecules obtained from small-angle neutron scattering (SANS) measurements are reported. The surfactant concentration and solution temperature were varied systematically. A survey of the physical models and evaluation algorithms applied for SANS are presented. By utilizing a new least square fitting algorithm, the formation and annihilation parameters of orthopositronium in the micellar pseudophase and in the aqueous solvent is deduced by evaluating positron lifetime spectra measured by conventional technqiues. (R.P.) 157 refs.; 10 figs

  6. 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)

  7. Sodium diffusion in boroaluminosilicate glasses

    DEFF Research Database (Denmark)

    Smedskjaer, Morten M.; Zheng, Qiuju; Mauro, John C.

    2011-01-01

    of isothermal sodium diffusion in BAS glasses by ion exchange, inward diffusion, and tracer diffusion experiments. By varying the [SiO2]/[Al2O3] ratio of the glasses, different structural regimes of sodium behavior are accessed. We show that the mobility of the sodium ions decreases with increasing [SiO2]/[Al2O......Understanding the fundamentals of alkali diffusion in boroaluminosilicate (BAS) glasses is of critical importance for advanced glass applications, e.g., the production of chemically strengthened glass covers for personal electronic devices. Here, we investigate the composition dependence...

  8. Anisotropy in elastic properties of lithium sodium sulphate ...

    Indian Academy of Sciences (India)

    Anisotropy in elastic properties of lithium sodium sulphate hexahydrate single crystal—An ultrasonic study. GEORGE VARUGHESE. ,∗. , A S KUMAR†, J PHILIP†† and GODFREY LOUIS#. Department of Physics, Catholicate College, Pathanamthitta 689 648, India. †SPAP, M.G. University, Kottayam 686 560, India. ††STIC ...

  9. calcium sulphate hemihydrate and bioactive glass composites for ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 41; Issue 2. In vitro bioactivity evaluation of α -calcium sulphate hemihydrate and bioactive glass composites for their potential use in bone regeneration. YANYAN ZHENG CHENGDONG XIONG DUJUAN ZHANG LIFANG ZHANG. Volume 41 Issue 2 April 2018 Article ID ...

  10. Sodium Sulphate Effect on Cement Produced with Building Stone Waste

    Directory of Open Access Journals (Sweden)

    Emre Sancak

    2015-01-01

    Full Text Available In this study, the blended cements produced by using the building stone waste were exposed to sulphate solution and the cement properties were examined. Prepared mortar specimens were cured under water for 28 days and then they were exposed to three different proportions of sodium sulphate solution for 125 days. Performances of cements were determined by means of compressive strength and tensile strength tests. The broken parts of some mortar bars were examined with scanning electron microscope (SEM. Besides, they were left under moist atmosphere and their length change was measured and continuously monitored for period of 125 days. In blended cements, solely cements obtained by replacing 10–20% of diatomites gave similar strength values with ordinary Portland cement (CEM I 42.5R at the ages of 7, 28, and 56 days. In all mortar specimens that included either waste andesite (AP or marble powder (MP showed best performance against very severe effective sodium sulphate solutions (13500 mg/L.

  11. Molecular structure of dextran sulphate sodium in aqueous environment

    Science.gov (United States)

    Yu, Miao; Every, Hayley A.; Jiskoot, Wim; Witkamp, Geert-Jan; Buijs, Wim

    2018-03-01

    Here we propose a 3D-molecular structural model for dextran sulphate sodium (DSS) in a neutral aqueous environment based on the results of a molecular modelling study. The DSS structure is dominated by the stereochemistry of the 1,6-linked α-glucose units and the presence of two sulphate groups on each α-glucose unit. The structure of DSS can be best described as a helix with various patterns of di-sulphate substitution on the glucose rings. The presence of a side chain does not alter the 3D-structure of the linear main chain much, but affects the overall spatial dimension of the polymer. The simulated polymers have a diameter similar to or in some cases even larger than model α-hemolysin nano-pores for macromolecule transport in many biological processes, indicating a size-limited translocation through such pores. All results of the molecular modelling study are in line with previously reported experimental data. This study establishes the three-dimensional structure of DSS and summarizes the spatial dimension of the polymer, serving as the basis for a better understanding on the molecular level of DSS-involved electrostatic interaction processes with biological components like proteins and cell pores.

  12. Sulphate removal from sodium sulphate-rich brine and recovery of barium as a barium salt mixture.

    Science.gov (United States)

    Vadapalli, Viswanath R K; Zvimba, John N; Mulopo, Jean; Motaung, Solly

    2013-01-01

    Sulphate removal from sodium sulphate-rich brine using barium hydroxide and recovery of the barium salts has been investigated. The sodium sulphate-rich brine treated with different dosages of barium hydroxide to precipitate barium sulphate showed sulphate removal from 13.5 g/L to less than 400 mg/L over 60 min using a barium to sulphate molar ratio of 1.1. The thermal conversion of precipitated barium sulphate to barium sulphide achieved a conversion yield of 85% using coal as both a reducing agent and an energy source. The recovery of a pure mixture of barium salts from barium sulphide, which involved dissolution of barium sulphide and reaction with ammonium hydroxide resulted in recovery of a mixture of barium carbonate (62%) and barium hydroxide (38%), which is a critical input raw material for barium salts based acid mine drainage (AMD) desalination technologies. Under alkaline conditions of this barium salt mixture recovery process, ammonia gas is given off, while hydrogen sulfide is retained in solution as bisulfide species, and this provides basis for ammonium hydroxide separation and recovery for reuse, with hydrogen sulfide also recoverable for further industrial applications such as sulfur production by subsequent stripping.

  13. Degradation of wall paints due to sodium sulphate and sodium chloride crystallization

    Directory of Open Access Journals (Sweden)

    Díaz Gonçalves, T.

    2003-03-01

    Full Text Available A test method for evaluating wall paints behaviour to soluble salts crystallization was developed at LNEC. in the present paper, a recent set of tests is described and discussed. The major objectives were: analysing and comparing the behaviour of a common emulsion {"plastic" paint and a silicate-based paint; observing and comparing the effect of sodium sulphate, sodium chloride and distilled water on the paints and on a non-painted stone; evaluating this test method adequacy and effectiveness. The silicate-based paint showed a resistance to soluble salts crystallization greater than the one of the plastic paint. However, the degradation pattern of the silicate-based paint (blistering of a filmic layer was similar to the one of organic paints and distinct from the one of pure mineral paints. The amount of damage that a saline solution can cause to wall paints cannot be inferred from the amount of damage it can cause to stone. Sodium chloride seems to be able to cause more severe degradation to wall paints than sodium sulphate. To the unpainted stone, sodium sulphate seems to be more damaging than sodium chloride. The test method seems adequate to observe and compare the behaviour of wall paints under soluble salts action. However, lower (around 0.5% concentrations for both sodium sulphate and sodium chloride should be tested in the future.

    RESUMEN En el LNEC se desarrolló una metodología de ensayo para evaluar la respuesta de pinturas aplicadas sobre paredes, frente a la cristalización de sales solubles. En este trabajo, se describen y discuten un conjunto de ensayos recientes. Los principales objetivos fueron: el análisis y la comparación del comportamiento de una pintura de emulsión común {''pintura plástica" y la de una pintura de silicato; la observación y la comparación de los efectos del sulfato de sodio, del cloruro de sodio y del agua destilada sobre las pinturas y sobre piedra no pintada; la evaluación de la adecuaci

  14. 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)

  15. Mixed cation effect in sodium aluminosilicate glasses

    DEFF Research Database (Denmark)

    Kjeldsen, Jonas; Smedskjær, Morten Mattrup; Mauro, John C.

    , network structure, and the resistances associated with the deformation processes in mixed cation glasses by partially substituting magnesium for calcium and calcium for lithium in sodium aluminosilicate glasses. We use Raman and 27Al NMR spectroscopies to obtain insights into the structural...

  16. Composition and structure of an iron-bearing, layered double hydroxide (LDH) - Green rust sodium sulphate

    DEFF Research Database (Denmark)

    Christiansen, B. C.; Balic-Zunic, T.; Petit, P. O.

    2009-01-01

    with Fe(II) and Fe(III) in an ordered distribution. The interlayers contain sulphate, water and sodium in an arrangement characteristic for the nikischerite group. The crystal structure is highly disordered by slacking faults. The composition, formula and crystallographic parameters are: NaFe(II)(6)Fe...

  17. Electrochemical study in the molten sodium acid sulphate - potassium acid sulphate eutectic

    International Nuclear Information System (INIS)

    Le Ber, F.

    1964-01-01

    The general properties of the NaHSO 4 - KHSO 4 molten eutectic resemble those of neutral sulphates and those of concentrated H 2 SO 4 . We have been able to show the existence in solution of the ions HSO - 4 SO 2- 4 , and H 3 O + , these last being formed by the action of the HSO - 4 ions on dissolved H 2 O. The electro-active zone with a polished platinum electrode is limited in oxidation by the ions H 3 O + and SO 2- 4 , and in reduction by the protons of HSO - 4 . We have compared the electro-active zones obtained with different electrodes (Ag-Au-graphite-mercury). We have considered the dissolution of a few metallic oxides and halides. This work shows the role as O 2- ion acceptors of HSO - 4 ions. We have undertaken an electro-chemical study of a few oxido-reduction Systems: H + / H 2 , Ag↓ / Ag (1), the vanadium and uranium Systems, those of mercury Hg↓ / Hg 2- 2 and of gold Au/Au 3+ , then of the attack by the solvent of a few common metals such as aluminium, iron, copper and nickel. The study of silver Systems has made it possible to obtain the solubility products of AgCl and AgBr and to consider the possibility of coulometric titration Cl - ions with Ag + ions. We have shown the existence of various chemical species of vanadium which may exist in the molten eutectic. (author) [fr

  18. Influence of Valsartan on the thermodynamics of micellization of anionic surfactant Sodium Dodecyl Sulphate

    Directory of Open Access Journals (Sweden)

    Stopková L.

    2016-12-01

    Full Text Available In this manuscript was investigated behaviour of drug valsartan by micellar media of anionic surfactant sodium dodecyl sulphate. As the method was used electrical conductivity for the determination of critical micelle concentration at different temperatures (T = 293.15 - 313.15 K, as well as calculated thermodynamic parameters like standard Gibbs free energy, enthalpy and entropy of micellization. According to contribution of Gibbs free energy is the process of micellization primarily controlled by entropy. Solubilization of valsartan was studied in surfactant system at 298.15 K and physiological conditions pH 7.4 using UV-spectrophotometry at different concentration range (0.001 - 0.07 mol/l of sodium dodecyl sulphate. The solubilization of drug was observed with increasing concentration of surfactant in aqueous solution.

  19. Physiochemical properties and reproducibility of air-based sodium tetradecyl sulphate foam using the Tessari method.

    Science.gov (United States)

    Watkins, Mike R; Oliver, Richard J

    2017-07-01

    Objectives The objectives were to examine the density, bubble size distribution and durability of sodium tetradecyl sulphate foam and the consistency of production of foam by a number of different operators using the Tessari method. Methods 1% and 3% sodium tetradecyl sulphate sclerosant foam was produced by an experienced operator and a group of inexperienced operators using either a 1:3 or 1:4 liquid:air ratio and the Tessari method. The foam density, bubble size distribution and foam durability were measured on freshly prepared foam from each operator. Results The foam density measurements were similar for each of the 1:3 preparations and for each of the 1:4 preparations but not affected by the sclerosant concentration. The bubble size for all preparations were very small immediately after preparation but progressively coalesced to become a micro-foam (foams developed liquid more rapidly when made in a 1:3 ratio (37 s) than in a 1:4 ratio (45 s) but all combinations took similar times to reach 0.4 ml liquid formation. For all the experiments, there was no statistical significant difference between operators. Conclusions The Tessari method of foam production for sodium tetradecyl sulphate sclerosant is consistent and reproducible even when made by inexperienced operators. The best quality foam with micro bubbles should be used within the first minute after production.

  20. Viscosity properties of sodium borophosphate glasses

    International Nuclear Information System (INIS)

    Gaylord, S.; Tincher, B.; Petit, L.; Richardson, K.

    2009-01-01

    The viscosity behavior of (1 - x)NaPO 3 -xNa 2 B 4 O 7 glasses (x = 0.05-0.20) have been measured as a function of temperature using beam-bending and parallel-plate viscometry. The viscosity was found to shift to higher temperatures with increasing sodium borate content. The kinetic fragility parameter, m, estimated from the viscosity curve, decreases from 52 to 33 when x increases from 0.05 to 0.20 indicating that the glass network transforms from fragile to strong with the addition of Na 2 B 4 O 7 . The decrease in fragility with increasing x is due to the progressive depolymerization of the phosphate network by the preferred four-coordinated boron atoms present in the low alkali borate glasses. As confirmed by Raman spectroscopy increasing alkali borate leads to enhanced B-O-P linkages realized with the accompanying transition from solely four-coordinated boron (in BO 4 units) to mixed BO 4 /BO 3 structures. The glass viscosity characteristics of the investigated glasses were compared to those of P-SF67 and N-FK5 commercial glasses from SCHOTT. We showed that the dependence of the viscosity of P-SF67 was similar to the investigated glasses due to similar phosphate network organization confirmed by Raman spectroscopy, whereas N-FK5 exhibited a very different viscosity curve and fragility parameter due to its highly coordinated silicate network

  1. Effects of carbonate and sulphate ions in synthetic groundwater on high-level waste glass leaching

    International Nuclear Information System (INIS)

    Kamizono, H.

    1990-01-01

    This laboratory experiment aims to examine the effects of rare earth carbonate and sulphate ions, that are naturally present in underground water, have on glass used to store high-level radioactive waste for disposal underground. Borosilicate glass (or HLW glass) is stored under observation on the land surface for several decades before being buried deep below ground in geological disposal sites. Two types of precipitation occur during leaching from the glass, immediate formation of a hydrated surface layer and slow precipitation from concentration in the leachates. This slow process of some elements precipitating onto the glass surface or into the leachates is examined in this experiment using scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). Carbonates from rare-earth elements are found in the synthetic groundwater used. It is shown that carbonate and sulphate ions will affect leaching and will occur in geological disposal sites. Other particles were also observed to precipitate using SEM-EDX. (author)

  2. 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)

  3. Exacerbation of alopecia areata: A possible complication of sodium tetradecyl sulphate foam sclerotherapy treatment for varicose veins

    Directory of Open Access Journals (Sweden)

    Mark S Whiteley

    2017-05-01

    Full Text Available A 40-year-old woman with a history of alopecia areata related to stress or hormonal changes was treated for bilateral primary symptomatic varicose veins (CEAP clinical score C2S of pelvic origin, using a staged procedure. Her first procedure entailed pelvic vein embolisation of three pelvic veins using 14 coils and including foam sclerotherapy of the tributaries, using 3% sodium tetradecyl sulphate. Following this procedure, she had an exacerbation of alopecia areata with some moderate shedding of hair. Subsequently, she underwent endovenous laser ablation under local anaesthetic without incident. Seven months after the pelvic vein embolisation, she underwent foam sclerotherapy of leg and labial varicose veins using sodium tetradecyl sulphate. Two days following this procedure, she had a severe exacerbation of alopecia areata with gross shedding of hair. These two episodes of exacerbation of alopecia areata appear to be associated with sodium tetradecyl sulphate foam sclerotherapy of veins.

  4. Exacerbation of alopecia areata: A possible complication of sodium tetradecyl sulphate foam sclerotherapy treatment for varicose veins.

    Science.gov (United States)

    Whiteley, Mark S; Smith, Victoria C

    2017-01-01

    A 40-year-old woman with a history of alopecia areata related to stress or hormonal changes was treated for bilateral primary symptomatic varicose veins (CEAP clinical score C2S) of pelvic origin, using a staged procedure. Her first procedure entailed pelvic vein embolisation of three pelvic veins using 14 coils and including foam sclerotherapy of the tributaries, using 3% sodium tetradecyl sulphate. Following this procedure, she had an exacerbation of alopecia areata with some moderate shedding of hair. Subsequently, she underwent endovenous laser ablation under local anaesthetic without incident. Seven months after the pelvic vein embolisation, she underwent foam sclerotherapy of leg and labial varicose veins using sodium tetradecyl sulphate. Two days following this procedure, she had a severe exacerbation of alopecia areata with gross shedding of hair. These two episodes of exacerbation of alopecia areata appear to be associated with sodium tetradecyl sulphate foam sclerotherapy of veins.

  5. Effects of Topical Corticosteroid and Tacrolimus on Ceramides and Irritancy to Sodium Lauryl Sulphate in Healthy Skin

    DEFF Research Database (Denmark)

    Jungersted, Jakob Mutanu; Høgh, Julie Kaae; Hellgren, Lars

    2011-01-01

    twice daily for one week with betamethasone, tacrolimus, emollient, or left untreated, respectively. After one week each area was challenged with a 24 h sodium lauryl sulphate patch test. The lipids were collected using the cyanoacrylate method and evaluated by high performance thin layer chromatography...... found between treatment regimes. Pretreatment with betamethasone (p = 0.01) or with tacrolimus (p = 0.001) causes a decreased inflammatory response to sodium lauryl sulphate compared with emollient. In conclusion, treatment with betamethasone and tacrolimus has a positive effect on the ceramide...

  6. Characterization and reactivity of sodium aluminoborosilicate glass fiber surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz Rivera, Lymaris, E-mail: luo105@psu.edu [Materials Research Institute, Pennsylvania State University, University Park, PA 16802 (United States); Bakaev, Victor A.; Banerjee, Joy [Materials Research Institute, Pennsylvania State University, University Park, PA 16802 (United States); Mueller, Karl T. [Department of Chemistry, Pennsylvania State University, University Park, PA 16802 (United States); Pantano, Carlo G. [Materials Research Institute, Pennsylvania State University, University Park, PA 16802 (United States); Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802 (United States)

    2016-05-01

    Highlights: • XPS revealed that these fiber surfaces contain sodium carbonate weathering products. • IGC–MS data confirms the products of acetic acid reaction with sodium carbonate. • NMR data shows two closely spaced, but distinct sodium carboxylate peaks. • Acetic acid reacts with both sodium in the glass and sodium in the sodium carbonate. - Abstract: Multicomponent complex oxides, such as sodium aluminoborosilicate glass fibers, are important materials used for thermal insulation in buildings and homes. Although the surface properties of single oxides, such as silica, have been extensively studied, less is known about the distribution of reactive sites at the surface of multicomponent oxides. Here, we investigated the reactivity of sodium aluminoborosilicate glass fiber surfaces for better understanding of their interface chemistry and bonding with acrylic polymers. Acetic acid (with and without a {sup 13}C enrichment) was used as a probe representative of the carboxylic functional groups in many acrylic polymers and adhesives. Inverse gas chromatography coupled to a mass spectrometer (IGC–MS), and solid state nuclear magnetic resonance (NMR), were used to characterize the fiber surface reactions and surface chemical structure. In this way, we discovered that both sodium ions in the glass surface, as well as sodium carbonate salts that formed on the surface due to the intrinsic reactivity of this glass in humid air, are primary sites of interaction with the carboxylic acid. Surface analysis by X-ray photoelectron spectroscopy (XPS) confirmed the presence of sodium carbonates on these surfaces. Computer simulations of the interactions between the reactive sites on the glass fiber surface with acetic acid were performed to evaluate energetically favorable reactions. The adsorption reactions with sodium in the glass structure provide adhesive bonding sites, whereas the reaction with the sodium carbonate consumes the acid to form sodium-carboxylate, H

  7. Sodium Is Not Essential for High Bioactivity of Glasses

    Science.gov (United States)

    Chen, Xiaojing; Chen, Xiaohui; Brauer, Delia S.; Wilson, Rory M.; Law, Robert V.; Hill, Robert G.; Karpukhina, Natalia

    2017-01-01

    This study aims to demonstrate that excellent bioactivity of glass can be achieved without the presence of an alkali metal component in glass composition. In vitro bioactivity of two sodium-free glasses based on the quaternary system SiO2-P2O5-CaO-CaF2 with 0 and 4.5 mol% CaF2 content was investigated and compared with the sodium containing glasses with equivalent amount of CaF2. The formation of apatite after immersion in Tris buffer was followed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), 31P and 19F solid state MAS-NMR. The dissolution study was completed by ion release measurements in Tris buffer. The results show that sodium free bioactive glasses formed apatite at 3 hours of immersion in Tris buffer, which is as fast as the corresponding sodium containing composition. This signifies that sodium is not an essential component in bioactive glasses and it is possible to make equally degradable bioactive glasses with or without sodium. The results presented here also emphasize the central role of the glass compositions design which is based on understanding of structural role of components and/or predicting the network connectivity of glasses. PMID:29271977

  8. Effects of Manganese (Ii Sulphate on Structural, Spectral, Optical, Thermal and Mechanical Properties of L-Alanine Sodium Sulphate Single Crystals

    Directory of Open Access Journals (Sweden)

    F. Praveena

    2017-04-01

    Full Text Available New Non-linear Optical materials have been attracting in the research world for their potential applications in emerging opto-electronic technology. The dipolar nature of amino acid leads to peculiar physical and chemical properties, thus making a good candidate for NLO applications. Single crystals of manganese(II sulphate doped L-Alanine sodium sulphate(LASS has been synthesized by slow evaporation technique. Structural property of the grown crystals are characterized by X-ray powder diffraction,FT-IR spectral analysis conforms all the functional groups. Thermogravity (TG and differential themogravimetric (DTA analysis have been performed to study the thermal stability of the crystals. The second harmonic generation efficiency was measured by Kurtz-Perry powder technique. The transmission and absorption of electromagnetic radiation is analysed through UV-VIS spectrum. Microhardness was measured at different applied load to understand the mechanical stability of the crystal.

  9. Removal of sodium lauryl sulphate by coagulation/flocculation with Moringa oleifera seed extract.

    Science.gov (United States)

    Beltrán-Heredia, J; Sánchez-Martín, J

    2009-05-30

    Among other natural flocculant/coagulant agents, Moringa oleifera seed extract ability to remove an anionic surfactant has been evaluated and it has been found to be very interesting. Sodium lauryl sulphate was removed from aqueous solutions up to 80% through coagulation/flocculation process. pH and temperature were found to be not very important factors in removal efficiency. Freundlich (F), Frumkin-Fowler-Guggenheim (FFG) and Gu-Zhu (GZ) models were used to adjust experimental data in a solid-liquid adsorption hypothesis. Last one resulted to be the most accurate one. Several data fit parameters were determined, as Freundlich order, which was found to be 1.66, Flory-Huggins interaction parameter from FFG model, which was found to be 4.87; and limiting Moringa surfactant adsorption capacity from GZ model, which was found to be 2.13 x 10(-3)mol/g.

  10. Analysis of aqueous humour in uveitis by high performance liquid chromatography and sodium dodecyl sulphate-polyacrylamide gel electrophoresis

    NARCIS (Netherlands)

    Murray, P. I.; Hoekzema, R.; Luyendijk, L.; Kijlstra, A.

    1992-01-01

    Aqueous humour from patients with Fuchs' heterochromic cyclitis (FHC) and other types of uveitis was analysed by high performance liquid chromatography (HPLC) and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Using HPLC, the number of peaks and their respective elution times

  11. THERMOCHEMISTRY OF INTERACTION REACTIONS FOR SODIUM AND ALUMINUM SULPHATES WITH COMPONENTS OF HYDRATING PORTLAND CEMENT

    Directory of Open Access Journals (Sweden)

    P. I. Yukhnevskiy

    2018-01-01

    Full Text Available Chemical additives are widely used in the technology of concrete with the purpose to solve various problems and sulphate-containing additives-electrolytes are also used as accelerators for setting and hardening of cement. Action mechanism of additive accelerators for setting and hardening of cement is rather complicated and can not be considered as well-established. An influence of sulfate-containing additives such as sodium sulfate is reduced to acceleration of cement silicate phase hydration by increasing ionic strength of the solution. In addition to it, exchange reactions of anion additive with portlandite phase (Ca(OH2 and aluminate phases of hardening cement have a significant effect on hardening process that lead to formation of readily soluble hydroxides and hardly soluble calcium salts. The influence of sulfate-containing additives on properties of water cement paste and cement stone is quite diverse and depends on salt concentration and cation type. For example, the action of the aluminum sulphate additive becomes more complicated if the additive is subjected to hydrolysis in water, which is aggravated in an alkaline medium of the water cement paste. Formation of hydrolysis products and their reaction with aluminate phases and cement portlandite lead to a significant acceleration of setting. Thus, despite the similarity of additives ensuring participation of anions in the exchange reactions, the mechanism of their influence on cement setting and hardening varies rather significantly. The present paper considers peculiar features concerning the mechanism of interaction of sodium and aluminum sulfate additives in cement compositions from the viewpoint of thermochemistry. Thermochemical equations for reactions of sulfate-containing additives with phases of hydrated cement clinker have been given in the paper. The paper contains description how to calculate thermal effects of chemical reactions and determine an influence of the formed

  12. The application of the acoustic emission technique to stone decay by sodium sulphate in laboratory tests

    Directory of Open Access Journals (Sweden)

    Grossi, C. M.

    1997-03-01

    Full Text Available Acoustic emission was monitored during salt crystallisation cycles in order to study the mechanisms of rock deterioration by sodium sulphate in laboratory tests. Some porous carbonate stones used in Spanish monuments (Cathedral of Oviedo, Murcia and Seo Vella of Lérida were selected for this study. The acoustic emission detected during the different stages of the cycles (immersion, drying and cooling was interpreted to be the result of the salt behaviour inside the stone. The use of this technique has confirmed that this behaviour depends on salt characteristics (solubility, hydration state and polymorphism of anhydrous sodium sulphate and stone porosity and pore network.

    Para determinar los mecanismos de deterioro de las rocas debidos a la acción del sulfato de sodio, se ha registrado la emisión acústica durante ensayos de cristalización de sales en el laboratorio. Para ello, se han seleccionado tres piedras porosas carbonatadas utilizadas como materiales de construcción en monumentos españoles (Catedrales de Oviedo, Murcia y Seo Vella de Lérida. La emisión acústica detectada durante las diferentes etapas de los ciclos (inmersión, secado y enfriamiento se ha interpretado como debida al comportamiento de la sal en el interior de la piedra. Mediante esta técnica se ha confirmado que este comportamiento depende de las características de la sal (solubilidad, diferentes estados de hidratación y el polimorfismo del sulfato de sodio anhidro y de la porosidad y configuración del sistema poroso de las rocas.

  13. Structural Dependence of Physical Properties in Sodium Boroaluminosilicate Glasses

    DEFF Research Database (Denmark)

    Zheng, Qiuju; Potuzak, Marcel; Mauro, John C.

    Boroaluminosilicate glasses have found applications in many fields. The extent and nature of the mixing of network formers like SiO2, B2O3, and Al2O3 play an important role in controlling the macroscopic properties. To understand the structure-property correlations in these glasses, we study...... a series of sodium boroaluminosilicate glasses with various [Al2O3]/[SiO2] ratios to access different regimes of sodium behavior. We determine dynamic properties, elastic moduli, and hardness of these glasses. The results reveal an existence of local minimum for density, fragility index, Young’s and shear...

  14. Mixed alkaline earth effect in sodium aluminosilicate glasses

    DEFF Research Database (Denmark)

    Kjeldsen, Jonas; Smedskjær, Morten Mattrup; Mauro, John C.

    2013-01-01

    While the mixed alkali effect has received significant attention in the glass literature, the mixed alkaline earth effect has not been thoroughly studied. Here, we investigate the latter effect by partial substitution of magnesium for calcium in sodium aluminosilicate glasses. We use Raman and NMR...

  15. Inactivation of Listeria monocytogenes ATCC 7644 on tomatoes using sodium docecyl sulphate, levulinic acid and sodium hypochlorite solution

    Directory of Open Access Journals (Sweden)

    E. Mnyandu

    2015-06-01

    Full Text Available The human pathogen Listeria monocytogenes poses a serious threat to public health. A study was carried out to evaluate the effectiveness of four sanitizers, used individually or combined, against L. monocytogenes ATCC 7644. The contact times for bacteria and sanitizer were varied to 1, 3 and 5 minutes. Levulinic acid, sodium dodecyl sulphate (SDS, sodium hypochlorite solution (chlorine and a combination of SDS and levulinic acid (mixture were tested. Results revealed that 0.5% levulinic acid, when used individually, is capable of reducing the surviving colonies by 3.63 log CFU/mL, 4.05 log CFU/mL, 6.71 log CFU/mL after exposure for 1, 3 and 5 minutes respectively.SDS resulted in an 8 log CFU/mL reduction after 1, 3 and 5 minutes. A combination of 0.5% levulinic acid and 0.05% SDS caused a 3.69 log CFU /mL reduction, 4.4 log CFU/mL reduction, 7.97 log CFU/mL reduction for 1, 3 and 5 minutes respectively. Chlorine was the least effective with 2.93 log CFU/mL reduction, 3.16 log CFU/ mL reduction and 4.53 log CFU/ mL reduction respectively. When stored for up to 72 hours at 4°C, the surviving colonies remained viable and decreased in number significantly P < 0.05 = 0.001. The titratable acidity of samples treated with levulinic acid and samples treated with SDS/Lev mixture was lowered significantly compared to the control sample. No significant differences were noted in these same parameters for samples treated with chlorine or SDS. The application of SDS in the fresh produce industry as a sanitizing agent may be successful in eradicating or reducing the viability of L. monocytogenes on fresh produce, thereby replacing the routine chlorine washing.

  16. Somatostatin does not attenuate intestinal injury in dextran sodium sulphate-induced subacute colitis

    Directory of Open Access Journals (Sweden)

    J. D. van Bergeijk

    1998-01-01

    Full Text Available From several in vitro and in vivo studies involvement of som atostatin (SMS in intestinal inflammation emerge. Acute colitis induced in rats is attenuated by the long-acting SMS analogue octreotide. We studied the potential beneficial effect of SMS on non-acute experimental colitis. BALB/c mice received either saline, SMS-14 (36 or 120 μg daily or octreotide (3 μg daily subcutaneously delivered by implant osmotic pumps. A non-acute colitis was induced by administration of dextran sodium sulphate (DSS 10% in drinking water during 7 days. DSS evoked a mild, superficial pancolitis, most characterized by mucosal ulceration and submucosal influx of neutrophils. Neither SMS-14 nor octreotide reduced mucosal inflammatory score or macroscopical disease activity, although reduction of intestinal levels of interleukin1 β (IL-1 β, IL-6 and IL-10 during DSS was augmented both by SMS and octreotide. A slight increase of neutrophil influx was seen during SMS administration in animals not exposed to DSS. In conclusion, SMS or its long-acting analogue did not reduce intestinal inflammation in non-acute DSS-induced colitis. According to the cytokine profile observed, SMS-14 and octreotide further diminished the reduction of intestinal macrophage and Th2 lymphocyte activity.

  17. Photochemistry of aromatic ketones in sodium dodecyl sulphate micelles in the presence of unsaturated fatty acids

    Directory of Open Access Journals (Sweden)

    DEJAN Z. MARKOVIC

    2004-02-01

    Full Text Available Laser-flash photolysis has been employed to characterize the behaviour of the free radicals created in the photochemical reaction of benzophenone (BZP, as well as of its lipoidal derivative, benzophenone-4-heptyl-4’-pentanoic acid (BHPA, with chosen unsaturated fatty acids in sodium dodecyl sulphate micelles. The calculated rate constants were used to study the “cage effect”, i.e., the recombination of the created radical-pairs (BZP, BHPA ketyl radical - lipid radical inside the highly limited space of the SDS micelles. The “cage effect” appears to be the dominant event inside SDS micelles, dependent on the structure of both the reactants-precursors. The fractions of the initially created radical-pairs which escape the “cage effect” and exit into the surrounding aqueous phase do not exceed 16 %. This fact is of enormous importance for the self-control of the pathogenic process of lipid peroxidation.

  18. Exacerbation of alopecia areata: A possible complication of sodium tetradecyl sulphate foam sclerotherapy treatment for varicose veins

    OpenAIRE

    Whiteley, Mark S; Smith, Victoria C

    2017-01-01

    A 40-year-old woman with a history of alopecia areata related to stress or hormonal changes was treated for bilateral primary symptomatic varicose veins (CEAP clinical score C2S) of pelvic origin, using a staged procedure. Her first procedure entailed pelvic vein embolisation of three pelvic veins using 14 coils and including foam sclerotherapy of the tributaries, using 3% sodium tetradecyl sulphate. Following this procedure, she had an exacerbation of alopecia areata with some moderate shedd...

  19. Characterization of Fly and Bottom Ashes Mixtures Treated using Sodium Lauryl Sulphate and Polyvinyl Alcohol

    Directory of Open Access Journals (Sweden)

    Robert C.G.

    2018-01-01

    Full Text Available Malaysia promotes coal as an option for solid fuel in electric power generation. Demanding of electricity needs, therefore, has led to increase the coal consumption and thus producing more coal waste products. The disposal of coal waste ashes has been a main concern to power generation station due to the need of disposal sites and operational costs. This study investigates the composition of fly ash (FA and bottom ash (BA mixtures with difference component percentage treated with sodium lauryl sulphate (SLS and polyvinyl alcohol (PVA at 1.5 and 2.5 wt% solutions and examined in terms of specific gravity, pH, maximum dry density properties, and its surface morphology. Although the chemical composition of the SLS and PVA treated fly and bottom ashes studied in this current work is not altered extensively, significant changes could be observed in its physicochemical properties. Chemically treated fly and bottom ashes mixtures with SLS and PVA at 1.5 wt% solution exhibited specific gravity of 1.97 to 2.92 and high pH values within range of 9.28 to 10.52. The mixture of BA:FA=0:1 ratio depicting high maximum dry density of 1.35 to 1.56 g/cm3 in both SLS and PVA solutions at 1.5 and 2.5 wt%. Scanning electron microscopy image shows distinct surface morphologies of SLS-treated fly and bottom ashes mixture that the particles are packed closely, strongly bonded similar to popcorn shape due to the effect of active silanol groups acted on coal ashes surface with the presence of Al-O/Si-O/other oxides. These findings suggest that higher level of chemical interaction between the fly and bottom ashes particles, significantly enhances pozzolanic reactions such as shear strength, plasticity, cementing properties, and thus other engineering properties.

  20. Characterization of Fly and Bottom Ashes Mixtures Treated using Sodium Lauryl Sulphate and Polyvinyl Alcohol

    Science.gov (United States)

    Robert, C. G.; Ayob, A.; Zaki, M. F. Muhammad; Razali, M. E.; Lew, E. V.; Hong, P. Y.

    2018-03-01

    Malaysia promotes coal as an option for solid fuel in electric power generation. Demanding of electricity needs, therefore, has led to increase the coal consumption and thus producing more coal waste products. The disposal of coal waste ashes has been a main concern to power generation station due to the need of disposal sites and operational costs. This study investigates the composition of fly ash (FA) and bottom ash (BA) mixtures with difference component percentage treated with sodium lauryl sulphate (SLS) and polyvinyl alcohol (PVA) at 1.5 and 2.5 wt% solutions and examined in terms of specific gravity, pH, maximum dry density properties, and its surface morphology. Although the chemical composition of the SLS and PVA treated fly and bottom ashes studied in this current work is not altered extensively, significant changes could be observed in its physicochemical properties. Chemically treated fly and bottom ashes mixtures with SLS and PVA at 1.5 wt% solution exhibited specific gravity of 1.97 to 2.92 and high pH values within range of 9.28 to 10.52. The mixture of BA:FA=0:1 ratio depicting high maximum dry density of 1.35 to 1.56 g/cm3 in both SLS and PVA solutions at 1.5 and 2.5 wt%. Scanning electron microscopy image shows distinct surface morphologies of SLS-treated fly and bottom ashes mixture that the particles are packed closely, strongly bonded similar to popcorn shape due to the effect of active silanol groups acted on coal ashes surface with the presence of Al-O/Si-O/other oxides. These findings suggest that higher level of chemical interaction between the fly and bottom ashes particles, significantly enhances pozzolanic reactions such as shear strength, plasticity, cementing properties, and thus other engineering properties.

  1. Impact of basal diet on dextran sodium sulphate (DSS)-induced colitis in rats.

    Science.gov (United States)

    Boussenna, Ahlem; Goncalves-Mendes, Nicolas; Joubert-Zakeyh, Juliette; Pereira, Bruno; Fraisse, Didier; Vasson, Marie-Paule; Texier, Odile; Felgines, Catherine

    2015-12-01

    Dextran sodium sulphate (DSS)-induced colitis is a widely used model for inflammatory bowel disease. However, various factors including nutrition may affect the development of this colitis. This study aimed to compare and characterize the impact of purified and non-purified basal diets on the development of DSS-induced colitis in the rat. Wistar rats were fed a non-purified or a semi-synthetic purified diet for 21 days. Colitis was then induced in half of the rats by administration of DSS in drinking water (4% w/v) during the last 7 days of experimentation. At the end of the experimental period, colon sections were taken for histopathological examination, determination of various markers of inflammation (myeloperoxidase: MPO, cytokines) and oxidative stress (superoxide dismutase: SOD, catalase: CAT, glutathione peroxidase: GPx and glutathione reductase: GRed activities), and evaluation of the expression of various genes implicated in this disorder. DSS ingestion induced a more marked colitis in animals receiving the purified diet, as reflected by higher histological score and increased MPO activity. A significant decrease in SOD and CAT activities was also observed in rats fed the purified diet. Also, in these animals, administration of DSS induced a significant increase in interleukin (IL)-1α, IL-1β and IL-6. In addition, various genes implicated in inflammation were over-expressed after ingestion of DSS by rats fed the purified diet. These results show that a purified diet promotes the onset of a more severe induced colitis than a non-purified one, highlighting the influence of basal diet in colitis development.

  2. Anti-inflammatory effects of phytosteryl ferulates in colitis induced by dextran sulphate sodium in mice

    Science.gov (United States)

    Islam, M S; Murata, T; Fujisawa, M; Nagasaka, R; Ushio, H; Bari, A M; Hori, M; Ozaki, H

    2008-01-01

    Background and purpose: We have recently reported that phytosteryl ferulates isolated from rice bran inhibit nuclear factor-κB (NF-κB) activity in macrophages. In the present study, we investigated the effect of γ-oryzanol (γ-ORZ), a mixture of phytosteryl ferulates, cycloartenyl ferulate (CAF), one of the components of γ-ORZ, and ferulic acid (FA), a possible metabolite of γ-ORZ in vivo, on a model of colitis in mice. Experimental approach: We induced colitis with dextran sulphate sodium (DSS) in mice and monitored disease activity index (DAI), histopathology score, tissue myeloperoxidase (MPO) activity, mRNA expressions of cytokines and COX-2, colon length, antioxidant potency and NF-κB activity in colitis tissue. Key results: Both DAI and histopathology score revealed that DSS induced a severe mucosal colitis, with a marked increase in the thickness of the muscle layer, distortion and loss of crypts, depletion of goblet cells and infiltration of macrophages, granulocytes and lymphocytes. MPO activity, pro-inflammatory cytokines and COX-2 levels, NF-κB p65 nuclear translocation and inhibitory protein of nuclear factor-κB-α degradation levels were significantly increased in DSS-induced colitis tissues. γ-ORZ (50 mg kg−1 day−1 p.o.) markedly inhibited these inflammatory reactions and CAF had a similar potency. In vitro assay demonstrated that γ-ORZ and CAF had strong antioxidant effects comparable to those of α-tocopherol. Conclusions and implications: Phytosteryl ferulates could be new potential therapeutic and/or preventive agents for gastrointestinal inflammatory diseases. Their anti-inflammatory effect could be mediated by inhibition of NF-κB activity, which was at least partly due to the antioxidant effect of the FA moiety in the structure of phytosteryl ferulates. PMID:18536734

  3. Lactobacillus reuteri increases mucus thickness and ameliorates dextran sulphate sodium-induced colitis in mice.

    Science.gov (United States)

    Ahl, D; Liu, H; Schreiber, O; Roos, S; Phillipson, M; Holm, L

    2016-08-01

    The aim of this study was to investigate whether two Lactobacillus reuteri strains (rat-derived R2LC and human-derived ATCC PTA 4659 (4659)) could protect mice against colitis, as well as delineate the mechanisms behind this protection. Mice were given L. reuteri R2LC or 4659 by gavage once daily for 14 days, and colitis was induced by addition of 3% DSS (dextran sulphate sodium) to drinking water for the last 7 days of this period. The severity of disease was assessed through clinical observations, histological evaluation and ELISA measurements of myeloperoxidase (MPO) and pro-inflammatory cytokines from colonic samples. Mucus thickness was measured in vivo with micropipettes, and tight junction protein expression was assessed using immunohistochemistry. Colitis severity was significantly reduced by L. reuteri R2LC or 4659 when evaluated both clinically and histologically. The inflammation markers MPO, IL-1β, IL-6 and mKC (mouse keratinocyte chemoattractant) were increased by DSS and significantly reduced by the L. reuteri strains. The firmly adherent mucus thickness was reduced by DSS, but significantly increased by L. reuteri in both control and DSS-treated mice. Expression of the tight junction proteins occludin and ZO-1 was significantly increased in the bottom of the colonic crypts by L. reuteri R2LC. These results demonstrate that each of the two different L. reuteri strains, one human-derived and one-rat-derived, protects against colitis in mice. Mechanisms behind this protection could at least partly be explained by the increased mucus thickness as well as a tightened epithelium in the stem cell area of the crypts. © 2016 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  4. Unique sodium phosphosilicate glasses designed through extended topological constraint theory.

    Science.gov (United States)

    Zeng, Huidan; Jiang, Qi; Liu, Zhao; Li, Xiang; Ren, Jing; Chen, Guorong; Liu, Fude; Peng, Shou

    2014-05-15

    Sodium phosphosilicate glasses exhibit unique properties with mixed network formers, and have various potential applications. However, proper understanding on the network structures and property-oriented methodology based on compositional changes are lacking. In this study, we have developed an extended topological constraint theory and applied it successfully to analyze the composition dependence of glass transition temperature (Tg) and hardness of sodium phosphosilicate glasses. It was found that the hardness and Tg of glasses do not always increase with the content of SiO2, and there exist maximum hardness and Tg at a certain content of SiO2. In particular, a unique glass (20Na2O-17SiO2-63P2O5) exhibits a low glass transition temperature (589 K) but still has relatively high hardness (4.42 GPa) mainly due to the high fraction of highly coordinated network former Si((6)). Because of its convenient forming and manufacturing, such kind of phosphosilicate glasses has a lot of valuable applications in optical fibers, optical amplifiers, biomaterials, and fuel cells. Also, such methodology can be applied to other types of phosphosilicate glasses with similar structures.

  5. Study of Polymorphism of Borovanadate Glass of Sodium by Raman ...

    African Journals Online (AJOL)

    Study of Polymorphism of Borovanadate Glass of Sodium by Raman Spectroscopy Low Frequencies. MK Rabia, M Mayoufi, L Grosvalet, B Champagnon. Abstract. Sodium tetraborate (100 – x)(Na2B4O7.10H2O)– xV2O5, (x = 0 to 20 mole %) has been elaborated by splat cooling technique. Raman Measurements on the ...

  6. Advances in Glass Formulations for Hanford High-Alumimum, High-Iron and Enhanced Sulphate Management in HLW Streams-13000

    International Nuclear Information System (INIS)

    Kruger, Albert A.

    2013-01-01

    The current estimates and glass formulation efforts have been conservative in terms of achievable waste loadings. These formulations have been specified to ensure that the glasses are homogenous, contain essentially no crystalline phases, are processable in joule-heated, ceramic-lined melters and meet Hanford Tank Waste Treatment and Immobilization Plant (WTP) Contract terms. The WTP's overall mission will require the immobilization of tank waste compositions that are dominated by mixtures of aluminum (Al), chromium (Cr), bismuth (Bi), iron (Fe), phosphorous (P), zirconium (Zr), and sulphur (S) compounds as waste-limiting components. Glass compositions for these waste mixtures have been developed based upon previous experience and current glass property models. Recently, DOE has initiated a testing program to develop and characterize HLW glasses with higher waste loadings and higher throughput efficiencies. Results of this work have demonstrated the feasibility of increases in waste loading from about 25 wt% to 33-50 wt% (based on oxide loading) in the glass depending on the waste stream. In view of the importance of aluminum limited waste streams at Hanford (and also Savannah River), the ability to achieve high waste loadings without adversely impacting melt rates has the potential for enormous cost savings from reductions in canister count and the potential for schedule acceleration. Consequently, the potential return on the investment made in the development of these enhancements is extremely favorable. Glass composition development for one of the latest Hanford HLW projected compositions with sulphate concentrations high enough to limit waste loading have been successfully tested and show tolerance for previously unreported tolerance for sulphate. Though a significant increase in waste loading for high-iron wastes has been achieved, the magnitude of the increase is not as substantial as those achieved for high-aluminum, high-chromium, high-bismuth or sulphur

  7. Effects of topical corticosteroid and tacrolimus on ceramides and irritancy to sodium lauryl sulphate in healthy skin

    DEFF Research Database (Denmark)

    Jungersted, Jakob Mutanu; Høgh, Julie Kaae; Hellegren, Lars I

    2011-01-01

    twice daily for one week with betamethasone, tacrolimus, emollient, or left untreated, respectively. After one week each area was challenged with a 24 h sodium lauryl sulphate patch test. The lipids were collected using the cyanoacrylate method and evaluated by high performance thin layer chromatography......The skin barrier, located in the stratum corneum, is influenced mainly by the lipid and protein composition of this layer. In eczematous diseases impairment of the skin barrier is thought to be of prime importance. Topical anti-inflammatory drugs and emollients are the most widely used eczema...

  8. Sodium Tetradecyl Sulphate Direct Intralesional Sclerotherapy of Venous Malformations of the Vulva and Vagina: Report of Five Cases

    International Nuclear Information System (INIS)

    Krokidis, Miltiadis; Venetucci, Pietro; Hatzidakis, Adam; Iaccarino, Vittorio

    2011-01-01

    We report five cases of female patients affected by symptomatic focal external genital venous malformations treated with percutaneous direct intralesional injection of sodium tetradecyl sulphate (STS). All patients were referred because of discomfort and pain when sexual intercourse was attempted. Direct sclerotherapy with 3% STS was performed on a day-hospital basis with the patient under local anesthesia. Complete resolution of the symptoms was achieved in all cases. No major adverse effects were reported. Direct intralesional sclerotherapy with STS may be considered a safe and effective method for the treatment of female external genital malformation without the necessity of general anesthesia for pain control.

  9. Advances in Glass Formulations for Hanford High-Aluminum, High-Iron and Enhanced Sulphate Management in HLW Streams - 13000

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, Albert A. [WTP Engineering Division, United States Department of Energy, Office of River Protection, Post Office Box 450, Richland, Washington 99352 (United States)

    2013-07-01

    The current estimates and glass formulation efforts have been conservative in terms of achievable waste loadings. These formulations have been specified to ensure that the glasses are homogenous, contain essentially no crystalline phases, are processable in joule-heated, ceramic-lined melters and meet Hanford Tank Waste Treatment and Immobilization Plant (WTP) Contract terms. The WTP's overall mission will require the immobilization of tank waste compositions that are dominated by mixtures of aluminum (Al), chromium (Cr), bismuth (Bi), iron (Fe), phosphorous (P), zirconium (Zr), and sulphur (S) compounds as waste-limiting components. Glass compositions for these waste mixtures have been developed based upon previous experience and current glass property models. Recently, DOE has initiated a testing program to develop and characterize HLW glasses with higher waste loadings and higher throughput efficiencies. Results of this work have demonstrated the feasibility of increases in waste loading from about 25 wt% to 33-50 wt% (based on oxide loading) in the glass depending on the waste stream. In view of the importance of aluminum limited waste streams at Hanford (and also Savannah River), the ability to achieve high waste loadings without adversely impacting melt rates has the potential for enormous cost savings from reductions in canister count and the potential for schedule acceleration. Consequently, the potential return on the investment made in the development of these enhancements is extremely favorable. Glass composition development for one of the latest Hanford HLW projected compositions with sulphate concentrations high enough to limit waste loading have been successfully tested and show tolerance for previously unreported tolerance for sulphate. Though a significant increase in waste loading for high-iron wastes has been achieved, the magnitude of the increase is not as substantial as those achieved for high-aluminum, high-chromium, high-bismuth or

  10. Electrochemical study in the molten sodium acid sulphate - potassium acid sulphate eutectic; Etude electrochimique dans l'eutectique fondu sulfate acide de sodium - sulfate acide de potassium

    Energy Technology Data Exchange (ETDEWEB)

    Le Ber, F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    The general properties of the NaHSO{sub 4} - KHSO{sub 4} molten eutectic resemble those of neutral sulphates and those of concentrated H{sub 2}SO{sub 4}. We have been able to show the existence in solution of the ions HSO{sup -}{sub 4} SO{sup 2-}{sub 4}, and H{sub 3}O{sup +}, these last being formed by the action of the HSO{sup -}{sub 4} ions on dissolved H{sub 2}O. The electro-active zone with a polished platinum electrode is limited in oxidation by the ions H{sub 3}O{sup +} and SO{sup 2-}{sub 4}, and in reduction by the protons of HSO{sup -}{sub 4}. We have compared the electro-active zones obtained with different electrodes (Ag-Au-graphite-mercury). We have considered the dissolution of a few metallic oxides and halides. This work shows the role as O{sup 2-} ion acceptors of HSO{sup -}{sub 4} ions. We have undertaken an electro-chemical study of a few oxido-reduction Systems: H{sup +} / H{sub 2}, Ag{down_arrow} / Ag (1), the vanadium and uranium Systems, those of mercury Hg{down_arrow} / Hg{sup 2-}{sub 2} and of gold Au/Au{sup 3+}, then of the attack by the solvent of a few common metals such as aluminium, iron, copper and nickel. The study of silver Systems has made it possible to obtain the solubility products of AgCl and AgBr and to consider the possibility of coulometric titration Cl{sup -} ions with Ag{sup +} ions. We have shown the existence of various chemical species of vanadium which may exist in the molten eutectic. (author) [French] Les proprietes generales de l'eutectique NaHSO{sub 4} - KHSO{sub 4} fondu s'apparentent a celles des sulfates neutres et a celles de H{sub 2}SO{sub 4} concentre. Nous avons pu mettre en evidence l'existence en solution d'ions HSO{sup -}{sub 4}, SO{sup 2-}{sub 4},et H{sub 3}O{sup +}, ces derniers resultats de l'action des ions HSO{sup -}{sub 4} sur H{sup 2}O dissoute. Le domaine d'electroactivite a une electrode de platine poli est limite en oxydation par les ions H{sub 3}O{sup +} + SO{sup 2-}{sub 4} et en reduction par les

  11. Structure and DC conductivity of lead sodium ultraphosphate glasses

    International Nuclear Information System (INIS)

    Abid, M.; Et-tabirou, M.; Taibi, M.

    2003-01-01

    Glasses of (0.40-x)Na 2 O-xPbO-0.60P 2 O 5 system with (0≤x≤0.40) molar fraction have been prepared with a conventional melting procedure. Their physical, thermal and spectroscopic studies such as density, molar volume, glass transition temperature, ionic conductivity and infrared spectroscopy have been investigated. The density and thermal stability of theses glasses increase with the substitution of PbO for Na 2 O. The ionic conductivity increases substantially with increasing concentration of sodium oxide and diminishes with increasing PbO content. Fourier-transform infrared spectroscopy reveals the formation of P-O-Pb bonds in theses glasses. The formation of P-O-Pb bonds which replace P-O - ...Na + bonds is in accordance with variations of glass transition temperature (T g ), molar volume (V m ) and ionic conductivity (σ). The former bonds are the origin of the partial glass-forming ability of Pb 2+

  12. Structural relaxation dynamics and annealing effects of sodium silicate glass.

    Science.gov (United States)

    Naji, Mohamed; Piazza, Francesco; Guimbretière, Guillaume; Canizarès, Aurélien; Vaills, Yann

    2013-05-09

    Here we report high-precision measurements of structural relaxation dynamics in the glass transition range at the intermediate and short length scale for a strong sodium silicate glass during long annealing times. We evidence for the first time the heterogeneous dynamics at the intermediate range order by probing the acoustic longitudinal frequency in the GHz region by Brillouin light scattering spectroscopy. Or, from in-situ Raman measurements, we show that relaxation is indeed homogeneous at the interatomic length scale. Our results show that the dynamics at the intermediate range order contains two distinct relaxation time scales, a fast and a slow component, differing by about a 10-fold factor below Tg and approaching to one another past the glass transition. The slow relaxation time agrees with the shear relaxation time, proving that Si-O bond breaking constitutes the primary control of structural relaxation at the intermediate range order.

  13. Glass Formulation Development for INEEL Sodium-Bearing Waste

    International Nuclear Information System (INIS)

    Vienna, J.D.; Schweiger, M.J.; Smith, D.E.; Smith, H.D.; Crum, J.V.; Peeler, D.K.; Reamer, I.A.; Musick, C.A.; Tillotson, R.D.

    1999-01-01

    For about four decades, radioactive wastes have been collected and calcined from nuclear fuels reprocessing at the Idaho Nuclear Technology and Engineering Center (INTEC), formerly Idaho Chemical Processing Plant (ICPP). Over this time span, secondary radioactive wastes have also been collected and stored as liquid from decontamination, laboratory activities, and fuel-storage activities. These liquid wastes are collectively called sodium-bearing wastes (SBW). About 5.7 million liters of these wastes are temporarily stored in stainless steel tanks at the Idaho National Engineering and Environmental Laboratory (INEEL). Vitrification is being considered as an immobilization step for SBW with a number of treatment and disposal options. A systematic study was undertaken to develop a glass composition to demonstrate direct vitrification of INEEL's SBW. The objectives of this study were to show the feasibility of SBW vitrification, not a development of an optimum formulation. The waste composition is relatively high in sodium, aluminum, and sulfur. A specific composition and glass property restrictions, discussed in Section 2, were used as a basis for the development. Calculations based on first-order expansions of selected glass properties in composition and some general tenets of glass chemistry led to an additive (fit) composition (68.69 mass % SiO 2 , 14.26 mass% B 2 O 3 , 11.31 mass% Fe 2 O 3 , 3.08 mass% TiO 2 , and 2.67 mass % Li 2 O) that meets all property restrictions when melted with 35 mass % of SBW on an oxide basis, The glass was prepared using oxides, carbonates, and boric acid and tested to confirm the acceptability of its properties. Glass was then made using waste simulant at three facilities, and limited testing was performed to test and optimize processing-related properties and confirm results of glass property testing. The measured glass properties are given in Section 4. The viscosity at 1150 C, 5 Pa·s, is nearly ideal for waste-glass processing in

  14. Microbial Growth in the Magnesium- Chloride - Sodium- Sulphate Ion System: Implications for Habitability in Terrestrial and Extraterrestrial Salts

    Science.gov (United States)

    Loudon, C. M.; Aka, S.; Cockell, C. S.

    2017-12-01

    Icy moons in the outer solar system are key targets in the search for extra-terrestrial life as there is evidence that they harbour subsurface oceans. Observational evidence of icy moons such as Europa suggest that these likely brine oceans should be composed of chloride and sulphate salts. The effects of the ions that compose these salts on biology and how the interactions between them can create geochemical and geophysical barriers to life are poorly understood. Here we present an in depth study of four microorganisms grown in solutions with varying combinations of the magnesium- chloride- sodium- sulphate ions. We find that the ion composition of the brine solution can have a large effect on growth. Whilst the water activity must be permissible for growth we found that this alone could not predict the effects of the ions on growth, chaotropic effects and ion specific effects influenced by the specific physiology of organisms are also evident. For this reason we conclude that simply knowing which salts are present on icy moons is not sufficient information to determine their potential habitibility. A full sample of any brine ocean would need to be studied to fully determine the potential for biology on these outer solar system satellites.

  15. Structure-topology-property correlations of sodium phosphosilicate glasses.

    Science.gov (United States)

    Hermansen, Christian; Guo, Xiaoju; Youngman, Randall E; Mauro, John C; Smedskjaer, Morten M; Yue, Yuanzheng

    2015-08-14

    In this work, we investigate the correlations among structure, topology, and properties in a series of sodium phosphosilicate glasses with [SiO2]/[SiO2 + P2O5] ranging from 0 to 1. The network structure is characterized by (29)Si and (31)P magic-angle spinning nuclear magnetic resonance and Raman spectroscopy. The results show the formation of six-fold coordinated silicon species in phosphorous-rich glasses. Based on the structural data, we propose a formation mechanism of the six-fold coordinated silicon, which is used to develop a quantitative structural model for predicting the speciation of the network forming units as a function of chemical composition. The structural model is then used to establish a temperature-dependent constraint description of phosphosilicate glass topology that enables prediction of glass transition temperature, liquid fragility, and indentation hardness. The topological constraint model provides insight into structural origin of the mixed network former effect in phosphosilicate glasses.

  16. radiation and electric field induced effects on the order-disorder phase in lithium sodium sulphate crystals

    Science.gov (United States)

    Hamed, A. E.; Kassem, M. E.; El-Wahidy, E. F.; El-Abshehy, M. A.

    1995-03-01

    The temperature dependence of specific heat at constant pressure, Cp(T), has been measured for lithium sodium sulphate, LiNaSo4 crystals, at different ?-radiation doses and external bias electric field (Eb), in the temperature range 300-900 K. A nonlinear dependence of transition temperature, T1 and a remarkable change in the thermodynamic parameters, were obtained as the effect of both electric field and ?-radiation. The effect of ?-radiation doses on the phase transition in LiNaSO4 crystals was explained as due to an internal bias field, Eb, originating from the interaction of polar defects with the order parameter of the host lattice. The internal bias field effect on the behaviour of Cp(T) in LiNaSO4 crystals was similar to that of the external electric field (E).

  17. Radioiodination of surface proteins of bull spermatozoa and their characterization by sodium dodecyl sulphate-polyacrylamide gel electrophoresis

    International Nuclear Information System (INIS)

    Vierula, M.

    1980-01-01

    Surface proteins of ejaculated bull spermatozoa were radioiodinated using Ma 125 I, solubilized and characterized by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The electron microscopic autoradiographs showed that the labelling was equally distributed to all parts of the spermatozoon and restricted to the sperm surface. The electrophoresis of solubilized radioactivity revealed 6 radioactive fractions with approximate molecular weights of 67 000-69 000, 47 000-50 000, 34 000-37 000, 25 000-28 000 and 14 000-16 000. The 6th fraction probably represented labelled lipids. The electrophoresis of radioiodinated seminal plasma proteins revealed only 2 radioactive protein peaks which coincided with the sperm surface protein fractions IV and V. (author)

  18. Impact of sodium dodecyl sulphate on the dissolution of poorly soluble drug into biorelevant medium from drug-surfactant discs

    DEFF Research Database (Denmark)

    Madelung, Peter; Ostergaard, Jesper; Bertelsen, Poul

    2014-01-01

    The purpose was to elucidate the mechanism of action of sodium dodecyl sulphate (SDS) on drug dissolution from discs under physiologically relevant conditions. The effect of incorporating SDS (4-30%, w/w) and drug into discs on the dissolution constant and solubility were evaluated for the poorly...... soluble drugs griseofulvin and felodipine in a biorelevant dissolution medium (BDM). Dissolution constants from dissolution profiles of drug discs with and without SDS were measured using miniaturized rotating disc dissolution. Solid state changes were investigated by X-ray diffraction. Solubility...... showed that the addition of SDS made the BS:PC micelles grow up to 2.5 times in volume. As a function of SDS addition, the dissolution constant showed an apparent exponential increase, while drug solubility showed a weak linear dependence. The pronounced effect on dissolution constant with SDS...

  19. Synthesis of Poly(para-phenylene terephthalamide and Preparation of Short Fibers: Effect of Sodium Sulphate on the Fibers

    Directory of Open Access Journals (Sweden)

    mohammad ali Semsarzadeh

    2012-12-01

    Full Text Available Kevlar is one of the fbers which is used in heavy industrial productions such as, shipping, military and weaving for reinforcement of composites. Initial polymer of Kevlar or poly(para-phenylene terephthalamide is an oriented liquid crystal polymer. Existence of aromatic group in the main chain leads to formation of rigid-rod molecules in the polymer, high strength and high modulus in it is fbers. Impurities in the polymer lead to decrease in fbers performance. In this research, poly(para - phenylene terephthalamide was synthesized from polycondensation of phenylene diamine and terephthaloyl dichloride in n-methyl pyrrolidone and calcium chloride (NMP-CaCl2 solution. Fourier transform infrared spectroscopy (FTIR and X-ray diffraction (XRD tests were carried out to characterize chemical bonds and crystalline plates of the polymer, respectively. Concentrated sulfuric acid is a solvent of poly(phenylene terephthalate therefore, this polymer was dissolved in concentreated sulfuric acid (96% and  the polymer solution was  injected  into  the cylindrical tank contain water. Sulfuric acid was transferred into water and the polymer was solidifed. After solidifcation,  tensile  force of vortex  led  to orientation of  rigid-rod polymer molecules  in direction of water rotation and  long fbers were formed from the polymer. The fbers were broken to short fbers by the same force of vortex. The short fbers were dried. SEM  images showed  the regular particles on  the surface of fbers. Results of FTIR and XRD proved that the regular particles are sodium sulphate salt. The effect of sodium sulphate salt as an impurity on the short fbers was studied.

  20. Characterization of ion distributions near the surface of sodium-containing and sodium-depleted calcium aluminosilicate glass melts

    International Nuclear Information System (INIS)

    Corrales, Louis R.; Du, Jincheng

    2006-01-01

    The distribution of cation and anion components of sodium containing calcium aluminosilicate glass was studied by classical molecular dynamics simulations in a high temperature melt in the bulk and at the vacuum-melt interface. A significant redistribution of the sodium and non-bridging oxygen ions was observed. Subsequently, a sodium depleted calcium aluminosilicate glass melt was simulated to determine the sensitivity of the redistribution of ions near the vacuum-melt interface to the presence of sodium ions. It is found that the thermodynamic equilibrium condition near a surface favors the enrichment of non-bridging oxygen ions that is closely associated with enrichment of the sodium ions

  1. Growth of sodium chlorate crystals in the presence of potassium sulphate

    Science.gov (United States)

    Kim, E. L.; Tsyganova, A. A.; Vorontsov, D. A.; Ovsetsina, T. I.; Katkova, M. R.; Lykov, V. A.; Portnov, V. N.

    2015-09-01

    In this work, we investigated the morphology and growth rates of NaClO3 crystals in solutions with K2SO4 additives. NaClO3 crystals were grown using the temperature gradient technique under concentration convection. We found that the crystal habitus changed from cubic to tetrahedral, and the growth of the cubic {100}, tetrahedral {111} and rhomb-dodecahedral {110} faces decelerated with an increase in the concentration of SO42- ions. The {110} face was the most and the {100} face was the least inhibited by sulphate ions. The mechanism of SO42- ions action is their adsorption on the crystal surface, which impedes attachment of the crystal's building units. We conclude that different atomic structure and charge state of various crystal faces determine their sensitivity to the action of the SO42- ions.

  2. Compatibility and stability of morphine sulphate and naloxone hydrochloride in 0.9% sodium chloride for injection.

    Science.gov (United States)

    Kistner, Charlotte; Ensom, Mary H H; Decarie, Diane; Lauder, Gillian; Carr, Roxane R

    2013-05-01

    Naloxone may be administered in conjunction with morphine to reduce the risk of opioid-induced pruritis. Combining these drugs for coadministration may be beneficial, but little is known about their physical compatibility and stability in combined solutions. To describe the physical compatibility and stability of morphine sulphate and naloxone hydrochloride (at various concentrations) in IV admixtures. The physical compatibility and stability of admixtures of morphine 1000 μg/mL and naloxone 4 μg/mL, 12.5 μg/mL, and 25 μg/mL in 0.9% sodium chloride were studied. For each concentration of naloxone, one bag was stored at room temperature (22°C) for 72 h and one bag was stored under refrigeration (4°C) for 30 days. For all preparations, physical characteristics, including pH, colour, and formation of precipitate, were evaluated. The samples were also analyzed by a stability-indicating high-performance liquid chromatographic method. Stability was defined as the retention of at least 90% of the initial concentration. No notable changes in pH or colour and no macroprecipitation were observed in any of the preparations after storage at 22°C for up to 72 h or at 4°C for up to 30 days. All preparations maintained more than 90% of the initial concentrations of morphine and naloxone at the end of the respective study periods. The calculated lower limit of the 95% confidence interval also indicated that 90% or more of the initial concentration remained at the end of each study period. Admixtures of morphine sulphate and naloxone hydrochloride were stable for 72 h at room temperature and for 30 days with refrigeration.

  3. Volume and structural relaxation in compressed sodium borate glass.

    Science.gov (United States)

    Svenson, Mouritz N; Youngman, Randall E; Yue, Yuanzheng; Rzoska, Sylwester J; Bockowski, Michal; Jensen, Lars R; Smedskjaer, Morten M

    2016-11-21

    The structure and properties of glass can be modified through compression near the glass transition temperature (T g ), and such modified structure and properties can be maintained at ambient temperature and pressure. However, once the compressed glass undergoes annealing near T g at ambient pressure, the modified structure and properties will relax. The challenging question is how the property relaxation is correlated with both the local and the medium-range structural relaxation. In this paper, we answer this question by studying the volume (density) and structural relaxation of a sodium borate glass that has first been pressure-quenched from its T g at 1 GPa, and then annealed at ambient pressure under different temperature-time conditions. Using 11 B MAS NMR and Raman spectroscopy, we find that the pressure-induced densification of the glass is accompanied by a conversion of six-membered rings into non-ring trigonal boron (B III ) units, i.e. a structural change in medium-range order, and an increase in the fraction of tetrahedral boron (B IV ), i.e. a structural change in short-range order. These pressure-induced structural conversions are reversible during ambient pressure annealing near T g , but exhibit a dependence on the annealing temperature, e.g. the ring/non-ring B III ratio stabilizes at different values depending on the applied annealing temperature. We find that conversions between structural units cannot account for the pressure-induced densification, and instead we suggest the packing of structural units as the main densification mechanism.

  4. Inactivation of heat adapted and chlorine adapted Listeria monocytogenes ATCC 7644 on tomatoes using sodium dodecyl sulphate, levulinic acid and sodium hypochlorite solution

    Directory of Open Access Journals (Sweden)

    Oluwatosin Ademola Ijabadeniyi

    2017-04-01

    Full Text Available The effectiveness of sodium dodecyl sulphate (SDS, sodium hypochlorite solution and levulinic acid in reducing the survival of heat adapted and chlorine adapted Listeria monocytogenes ATCC 7644 was evaluated. The results against heat adapted L. monocytognes revealed that sodium hypochlorite solution was the least effective, achieving log reduction of 2.75, 2.94 and 3.97 log colony forming unit (CFU/mL for 1, 3 and 5 minutes, respectively. SDS was able to achieve 8 log reduction for both heat adapted and chlorine adapted bacteria. When used against chlorine adapted L. monocytogenes sodium hypochlorite solution achieved log reduction of 2.76, 2.93 and 3.65 log CFU/mL for 1, 3 and 5 minutes, respectively. Using levulinic acid on heat adapted bacteria achieved log reduction of 3.07, 2.78 and 4.97 log CFU/mL for 1, 3, 5 minutes, respectively. On chlorine adapted bacteria levulinic acid achieved log reduction of 2.77, 3.07 and 5.21 log CFU/mL for 1, 3 and 5 minutes, respectively. Using a mixture of 0.05% SDS and 0.5% levulinic acid on heat adapted bacteria achieved log reduction of 3.13, 3.32 and 4.79 log CFU/mL for 1, 3 and 5 minutes while on chlorine adapted bacteria it achieved 3.20, 3.33 and 5.66 log CFU/mL, respectively. Increasing contact time also increased log reduction for both test pathogens. A storage period of up to 72 hours resulted in progressive log reduction for both test pathogens. Results also revealed that there was a significant difference (P≤0.05 among contact times, storage times and sanitizers. Findings from this study can be used to select suitable sanitizers and contact times for heat and chlorine adapted L. monocytogenes in the fresh produce industry.

  5. Partial Characterization of Biosurfactant from Lactobacillus pentosus and Comparison with Sodium Dodecyl Sulphate for the Bioremediation of Hydrocarbon Contaminated Soil

    Directory of Open Access Journals (Sweden)

    A. B. Moldes

    2013-01-01

    Full Text Available The capability of a cell bound biosurfactant produced by Lactobacillus pentosus, to accelerate the bioremediation of a hydrocarbon-contaminated soil, was compared with a synthetic anionic surfactant (sodium dodecyl sulphate SDS-. The biosurfactant produced by the bacteria was analyzed by Fourier transform infrared spectroscopy (FTIR that clearly indicates the presence of OH and NH groups, C=O stretching of carbonyl groups and NH nebding (peptide linkage, as well as CH2–CH3 and C–O stretching, with similar FTIR spectra than other biosurfactants obtained from lactic acid bacteria. After the characterization of biosurfactant by FTIR, soil contaminated with 7,000 mg Kg−1 of octane was treated with biosurfactant from L. pentosus or SDS. Treatment of soil for 15 days with the biosurfactant produced by L. pentosus led to a 65.1% reduction in the hydrocarbon concentration, whereas SDS reduced the octane concentration to 37.2% compared with a 2.2% reduction in the soil contaminated with octane in absence of biosurfactant used as control. Besides, after 30 days of incubation soil with SDS or biosurfactant gave percentages of bioremediation around 90% in both cases. Thus, it can be concluded that biosurfactant produced by L. pentosus accelerates the bioremediation of octane-contaminated soil by improving the solubilisation of octane in the water phase of soil, achieving even better results than those reached with SDS after 15-day treatment.

  6. Partial Characterization of Biosurfactant from Lactobacillus pentosus and Comparison with Sodium Dodecyl Sulphate for the Bioremediation of Hydrocarbon Contaminated Soil

    Science.gov (United States)

    Moldes, A. B.; Paradelo, R.; Vecino, X.; Cruz, J. M.; Gudiña, E.; Rodrigues, L.; Teixeira, J. A.; Domínguez, J. M.; Barral, M. T.

    2013-01-01

    The capability of a cell bound biosurfactant produced by Lactobacillus pentosus, to accelerate the bioremediation of a hydrocarbon-contaminated soil, was compared with a synthetic anionic surfactant (sodium dodecyl sulphate SDS-). The biosurfactant produced by the bacteria was analyzed by Fourier transform infrared spectroscopy (FTIR) that clearly indicates the presence of OH and NH groups, C=O stretching of carbonyl groups and NH nebding (peptide linkage), as well as CH2–CH3 and C–O stretching, with similar FTIR spectra than other biosurfactants obtained from lactic acid bacteria. After the characterization of biosurfactant by FTIR, soil contaminated with 7,000 mg Kg−1 of octane was treated with biosurfactant from L. pentosus or SDS. Treatment of soil for 15 days with the biosurfactant produced by L. pentosus led to a 65.1% reduction in the hydrocarbon concentration, whereas SDS reduced the octane concentration to 37.2% compared with a 2.2% reduction in the soil contaminated with octane in absence of biosurfactant used as control. Besides, after 30 days of incubation soil with SDS or biosurfactant gave percentages of bioremediation around 90% in both cases. Thus, it can be concluded that biosurfactant produced by L. pentosus accelerates the bioremediation of octane-contaminated soil by improving the solubilisation of octane in the water phase of soil, achieving even better results than those reached with SDS after 15-day treatment. PMID:23691515

  7. Effect of vehicles and sodium lauryl sulphate on xenobiotic permeability and stratum corneum partitioning in porcine skin

    International Nuclear Information System (INIS)

    Merwe, Deon van der; Riviere, Jim E.

    2005-01-01

    Dermal contact with potentially toxic agricultural and industrial chemicals is a common hazard encountered in occupational, accidental spill and environmental contamination scenarios. Different solvents and chemical mixtures may influence dermal absorption. The effects of sodium lauryl sulphate (SLS) on the stratum corneum partitioning and permeability in porcine skin of 10 agricultural and industrial chemicals in water, ethanol and propylene glycol were investigated. The chemicals were phenol, p-nitrophenol, pentachlorophenol, methyl parathion, ethyl parathion, chlorpyrifos, fenthion, simazine, atrazine and propazine. SLS decreased partitioning into stratum corneum from water for lipophilic compounds, decreased partitioning from propylene glycol and did not alter partitioning from ethanol. SLS effects on permeability were less consistent, but generally decreased permeability from water, increased permeability from ethanol and had an inconsistent effect on permeability from propylene glycol. It was concluded that, for the compounds tested, partitioning into the stratum corneum was determined by the relative solubility of the solute in the donor solvent and the stratum corneum lipids. Permeability, however, reflected the result of successive, complex processes and was not predictable from stratum corneum partitioning alone. Addition of SLS to solvents altered partitioning and absorption characteristics across a range of compounds, which indicates that partition coefficients or skin permeability from neat chemical exposure should be used with caution in risk assessment procedures for chemical mixtures

  8. Evidence of β-sheet structure induced kinetic stability of papain upon thermal and sodium dodecyl sulphate denaturation

    Directory of Open Access Journals (Sweden)

    Rašković Brankica

    2015-01-01

    Full Text Available Papain is a protease that consists of α-helical and β-sheet domains which unfold almost independently. Both, papain considerable thermal stability and sodium dodecyl sulphate (SDS resistance have been shown. However, the ability of each domain to unfold upon thermal and SDS denaturation has never been studied. This work shows that fruit papain has slightly higher thermal inactivation resistance when it is compared to stem papain with rather high activation energy (Ea of 223 ± 16 kJmol-1 and Tm50 value of 79 ± 2 °C. SDS resistance of fruit papain was estimated by SDS-PAGE analysis and activity staining. It has been noted that, in the presence of SDS, unless heat energy was applied in order to unfold papain, the protein remained active. Furthermore, it has been proven via Fourier transform infrared spectroscopy (FT-IR that α-helical domain of fruit papain is more prone to unfolding at elevated temperatures and in the presence of SDS then β-sheet rich domain. Thermal denaturation of papain without detergent present led to accelerated formation of aggregation specific intermolecular β-sheets as compared to native protein. Presented results are both, of fundamental and application importance. [Projekat Ministarstva nauke Republike Srbije, br. 172049

  9. ISOLATION OF EGG DROP SYNDROME VIRUS AND ITS MOLECULAR CHARACTERIZATION USING SODIUM DODECYL SULPHATE POLYACRYLAMIDE GEL ELECTROPHORESIS

    Directory of Open Access Journals (Sweden)

    M. H. Rasool, S. U. Rahman and M. K. Mansoor

    2005-10-01

    Full Text Available Six isolates of egg drop syndrome (EDS virus were recovered from five different outbreaks of EDS in commercial laying hens in and around Faisalabad. The aberrant eggs were fed to the susceptible laying hens for experimental induction of infection. The samples from infected birds (egg washing, cloacal swabs, oviducts and spleens were collected, processed and inoculated into 11-day old duck embryos. The presence of virus in harvested allanto-amniotic fluid was monitored by spot and microhaemagglutination tests and confirmed by haemagglutination inhibition and agar gel precipitation tests. The EDS virus grew well in duck embryos and agglutinated only avian but not mammalian red blood cells. These isolates were purified through velocity density gradient centrifugation. Protein concentration was determined through Lowry method and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE was conducted by loading 300 µg protein concentration on 12.5% gel using discontinuous buffer system. All the six isolates showed 13 polypeptides, which were identical to those described in the referral EDS-76 virus (strain-127. The molecular weights of the polypeptides ranged from 6.5 KDa to 126 KDa.

  10. A comparative study on production of stable carbon nano tube dispersions using gum arabic and sodium dodecyl sulphate

    International Nuclear Information System (INIS)

    Rashmi, W.; Ismail, A.F.; Jameel, A.T.; Yusof, F.; Khalid, M.; Mubarak, N.M.

    2009-01-01

    Full text: Improvements on the stability of carbon nano tube (CNT)-water suspensions are necessary to enhance the performance of CNT nano fluids. CNTs are usually packed into crystalline ropes that form strong networks due to Van der Waals attraction. Aggregation of these CNTs is obstacle to most of the applications which diminished its special properties. Thus, this paper aims to produce stable CNT dispersion using Gum Arabic (GA) and Sodium dodecyl sulphate (SDS) as dispersants. The CNT concentration is varied from 0.01-0.1 wt% while the concentration of dispersants is varied from 1-12 wt%, respectively. This work gives detailed information on effect of CNT concentration, dispersant concentration and sonication time on stability of CNT dispersions. UV-Vis Spectrophotometer was used to measure the concentration of CNTs with respect to sedimentation time. CNT-GA suspensions were found to be more stable compared to CNT-SDS suspensions. The homogeneous suspension of CNT-GA is stable for several months. (author)

  11. Release mechanism of doxazosin from carrageenan matrix tablets: Effect of ionic strength and addition of sodium dodecyl sulphate.

    Science.gov (United States)

    Kos, Petra; Pavli, Matej; Baumgartner, Saša; Kogej, Ksenija

    2017-08-30

    The polyelectrolyte matrix tablets loaded with an oppositely charged drug exhibit complex drug-release mechanisms. In this study, the release mechanism of a cationic drug doxazosin mesylate (DM) from matrix tablets based on an anionic polyelectrolyte λ-carrageenan (λ-CARR) is investigated. The drug release rates from λ-CARR matrices are correlated with binding results based on potentiometric measurements using the DM ion-sensitive membrane electrode and with molecular characteristics of the DM-λ-CARR-complex particles through hydrodynamic size measurements. Experiments are performed in solutions with different ionic strength and with the addition of an anionic surfactant sodium dodecyl sulphate (SDS). It is demonstrated that in addition to swelling and erosion of tablets, the release rates depend strongly on cooperative interactions between DM and λ-CARR. Addition of SDS at concentrations below its critical micelle concentration (CMC) slows down the DM release through hydrophobic binding of SDS to the DM-λ-CARR complex. On the contrary, at concentrations above the CMC SDS pulls DM from the complex by forming mixed micelles with it and thus accelerates the release. Results involving SDS show that the concentration of surfactants that are naturally present in gastrointestinal environment may have a great impact on the drug release process. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Elastic Properties and Structural Studies on Boro-Vanadate Glasses Containing Sulphate (SO42-) Ions

    Science.gov (United States)

    Reddy, M. Sudhakar; Gowda, V. C. Veeranna; Reddy, C. Narayana

    2011-12-01

    Elastic properties of xLi2SO4-16 Li2O-(84-x) [0.7 B2O3-0.3 V2O5] where (5≤x≥30) glasses have been prepared by melt quenching method and structural investigations were carried out using ultrasonic pulse echo overlap technique at a frequency of 10 MHz and at 300 K. The molar volume increases and the density decreases with the increase of Li2SO4 concentration due to the incorporation of SO42- ions into the modified macromolecular network. The addition of Li2SO4 content leads to loose packing structure which is attributed to volume increasing effect and the reduction in the vibrations of borate and vanadate lattices. Increase in Li24SO results in decreasing cross link density which in turn decreases elastic moduli. The results are discussed in view of its network structure. The structural groups [VOO3/2]0 and [BO3/2]0 modify preferentially. This preference in modification is decided by the electronegativity (χ) of the structural groups.

  13. Anti-irritant and anti-inflammatory effects of glycerol and xylitol in sodium lauryl sulphate-induced acute irritation.

    Science.gov (United States)

    Szél, E; Polyánka, H; Szabó, K; Hartmann, P; Degovics, D; Balázs, B; Németh, I B; Korponyai, C; Csányi, E; Kaszaki, J; Dikstein, S; Nagy, K; Kemény, L; Erős, G

    2015-12-01

    Glycerol is known to possess anti-irritant and hydrating properties and previous studies suggested that xylitol may also have similar effects. Our aim was to study whether different concentrations of these polyols restore skin barrier function and soothe inflammation in sodium lauryl sulphate (SLS)-induced acute irritation. The experiments were performed on male SKH-1 hairless mice. The skin of the dorsal region was exposed to SLS (5%) for 3 h alone or together with 5% or 10% of glycerol respectively. Further two groups received xylitol solutions (8.26% and 16.52% respectively) using the same osmolarities, which were equivalent to those of the glycerol treatments. The control group was treated with purified water. Transepidermal water loss (TEWL) and skin hydration were determined. Microcirculatory parameters of inflammation were observed by means of intravital videomicroscopy (IVM). Furthermore, accumulation of neutrophil granulocytes and lymphocytes, the expression of inflammatory cytokines and SLS penetration were assessed, as well. Treatment with the 10% of glycerol and both concentrations of xylitol inhibited the SLS-induced elevation of TEWL and moderated the irritant-induced increase in dermal blood flow and in the number of leucocyte-endothelial interactions. All concentrations of the applied polyols improved hydration and prevented the accumulation of lymphocytes near the treatment site. At the mRNA level, neither glycerol nor xylitol influenced the expression of interleukin-1 alpha. However, expression of interleukin-1 beta was significantly decreased by the 10% glycerol treatment, while expression of tumour necrosis factor-alpha decreased upon the same treatment, as well as in response to xylitol. Higher polyol treatments decreased the SLS penetration to the deeper layers of the stratum corneum. Both of the analysed polyols exert considerable anti-irritant and anti-inflammatory properties, but the effective concentration of xylitol is lower than that of

  14. Action of arginine for protection of ulcerative colitis by dextran sodium sulphate (DSS)

    International Nuclear Information System (INIS)

    Andrade, Maria Emilia Rabelo

    2016-01-01

    Recent studies have demonstrated the benefits of immunomodulators, such as arginine, in the regulation of inflammatory responses and trophism of the intestinal mucosa. The aim of this study was to evaluate the possible mechanisms action of arginine (pretreatment or treatment) in experimental model of ulcerative colitis induced by dextran sodium sulfate (DSS). C57BL/6 mice were randomized into 5 groups: Control group (C): standard diet and water; Arginine group (ARG): diet supplementation with arginine and water; Colitis group (COL): standard diet and DSS solution; Pretreated group (PT): diet supplementation with arginine before and during colitis induction; Treated group (T): diet supplementation with arginine during colitis induction. Colitis was induced by administration of 1.5% DSS for 5 days. After this, all the mice were euthanized and blood, organs and intestinal fluid were collected for carrying out analyzes. Parameters such as intestinal permeability (IP), bacterial translocation (BT), histological analysis (histological score, morphometric analysis, collagen and mucins stain), nitrate and nitrite, cytokines and chemokines, secretory immunoglobulin A (sIgA), inflammatory infiltrate and oxidative stress were performed. The ARG group did not show difference compared to group C in the investigated parameters (C vs ARG: p> 0.05). The COL group showed increased IP (C vs COL: p < 0.05) and BT (C vs COL: p <0.05). In the histological analysis, the COL group showed severe inflammation and reduction the crypts length. In addition, in the group COL observed increase infiltration of eosinophils, neutrophils and macrophages in the colon, increase cytokine IL-17 and chemokine KC in serum and oxidative stress in the colon (COL vs C: p <0.05). In the arginine-supplemented groups (PT and T) was observed decrease IP and BT to blood, liver and lung (PT and T vs Col: p <0.05). Histological analysis showed that the arginine (PT and T) preserved the intestinal mucosa and crypts

  15. sodium dodecyl sulphate (SDS)

    Indian Academy of Sciences (India)

    Unknown

    In contrast, much higher concentration of NaCl (2 M) is required for the salting-out effect of the dye–surfactant complex for conversion to the micellized form. Keywords. Cresyl violet; surfactant; salt effect; absorption; stopped-flow. 1. Introduction. Cresyl violet, a cationic dye (CV+, scheme 1) belonging to the phenoxazine ...

  16. Study of micellar solutions of the 'sodium lauryl sulphate-heavy water' system by using pulsed NMR

    International Nuclear Information System (INIS)

    Fouchet, C.

    1972-01-01

    This research thesis reports the study of the nuclear magnetic resonance of protons contained by micellar solutions of sodium lauryl sulphate and heavy water. Relaxation times have been measured with respect to various parameters: concentration, temperature, frequency. The author presents the main properties of micellar solutions and indicate the various possible movements. Then, he addresses the implemented technique, and shows that NMR is sensitive to short range interactions, and allows micellar movements to be studied over an extended rate range. Experimental results are then presented and interpreted [fr

  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. Structure and properties of sodium aluminosilicate glasses from molecular dynamics simulations

    DEFF Research Database (Denmark)

    Xiang, Ye; Du, Jincheng; Smedskjær, Morten Mattrup

    2013-01-01

    the recent Corning® Gorilla® Glass. In this paper, the structures of sodium aluminosilicate glasses with a wide range of Al/Na ratios (from 1.5 to 0.6) have been studied using classical molecular dynamics simulations in a system containing around 3000 atoms, with the aim to understand the structural role...

  19. Optical properties of thermally reduced bismuth-doped sodium aluminosilicate glasses

    DEFF Research Database (Denmark)

    Nielsen, K.H.; Smedskjær, Morten Mattrup; Yue, Yuanzheng

    Heat-treatment of multivalent ion containing glasses in a hydrogen atmosphere may cause both reduction of the multivalent ions and ionic inward diffusion, resulting in improved glass properties. Bismuth-doped glasses are also interesting objects not only concerning the reduction induced diffusion...... pressure of hydrogen. Here, we present results on the effect of the heat-treatment on the optical properties of bismuth-doped sodium aluminosilicate glasses.......Heat-treatment of multivalent ion containing glasses in a hydrogen atmosphere may cause both reduction of the multivalent ions and ionic inward diffusion, resulting in improved glass properties. Bismuth-doped glasses are also interesting objects not only concerning the reduction induced diffusion...

  20. Effect of silicate module of water glass on rheological parameters of poly(sodium acrylate)/sodium silicate hydrogels

    Science.gov (United States)

    Mastalska-Popiawska, J.; Izak, P.

    2017-01-01

    The poly(sodium acrylate)/sodium silicate hydrogels were synthesized in the presence of sodium thiosulphate and potassium persulphate as the redox initiators and N,N’-methylene-bisacrylamide as the cross-linking monomer. 20 wt% aqueous solution of sodium acrylate was polymerized together with water glass with different silicate modules (M) from 1.74 to 2.29, in three mass ratio of the monomer solution to the water glass 2:1, 1:1 and 1:2. Such obtained hybrid composites were rheologically tested using the oscillation method. It allowed to designate the crossover point during polymerization, as well as to define the viscoelastic properties of the casted hydrogel samples one week after the reaction. The obtained results of the oscillation measurements showed that cross-linking reaction proceeds very quickly and the lower the silicate module is, the process starts faster. After the completion of the reaction the silicate-polymer hydrogels are strongly elastic materials and the highest elasticity characterizes systems with the mass ratio 1:2, i.e. with the highest water glass content.

  1. Moessbauer effect study of oxidation and coordination states of iron in some sodium borate glasse:;

    International Nuclear Information System (INIS)

    Eissa, N.A.; Sanad, A.M.; Youssef, S.M.; El-Henawii, S.A.; Gomaa, S.Sh.; Mostafa, A.G.

    1980-01-01

    A structural study of some sodium borate glasses containing iron was carried out applying ME spectroscopy. Both oxidation and coordination states of iron were investigated under the effect of gradual replacing of sodium carbonate by sodium nitrate in the glass batches. The glasses were melted in porcelain crucibles using an electrically heated furnace at 1000+-10 deg C, then were quenched on a steel plate at room temperature (R.T.). The ME source was 20 mCi radioactive Co-57 in chromium. The obtained ME spectra indicated that at lower sodium nitrate content both Fe 2+ and Fe 3+ are present in these glasses. At moderate concentrations some Fe 3+ ions were separated in a crystalline phase and the rest of the iron ions appeared as ferric ions in glassy state. At high sodium nitrate content only Fe 3+ ions in glassy state were detected. The values of the ME parameters for all iron ions indicated that all of them are in the octahedral coordination state. The density measurements confirm the separation of a crystalline phase at moderate sodium nitrate content. (author)

  2. Optimization of the contents of hollow glass microsphere and sodium hexametaphosphate for glass fiber vacuum insulation panel

    Science.gov (United States)

    Li, C. D.; Chen, Z. F.; Zhou, J. M.

    2016-07-01

    In this paper, various additive amounts of hollow glass microspheres (HGMs) and sodium hexametaphosphate (SHMP) powders were blended with flame attenuated glass wool (FAGW) to form hybrid core materials (HCMs) through the wet method. Among them, the SHMP was dissolved in the glass fiber suspension and coated on the surface of glass fibers while the HGMs were insoluble in the glass fiber suspension and filled in the fiber-fiber pores. The average pore diameter of the FAGW/HGM HCMs was 8-11 μm which was near the same as that of flame attenuated glass fiber mats (FAGMs, i.e., 10.5 µm). The tensile strength of the SHMP coated FAGMs was enhanced from 160 N/m to 370 N/m when SHMP content increased from 0 wt.% to 0.2 wt.%. By contrast, the tensile strength of the FAGW/HGM HCMs decreased from 160 N/m to 40 N/m when HGM content increased from 0 wt.% to 50 wt.%. Both the FAGW/HGM HCMs and SHMP coated FAGMs were vacuumed completely to form vacuum insulation panels (VIPs). The results showed that both the addition of SHMP and HGM led a slight increase in the thermal conductivity of the corresponding VIPs. To obtain a high-quality VIP, the optimal SHMP content and HGM content in glass fiber suspension was 0.12-0.2 wt.% and 0 wt.%.

  3. Influence of sodium content on the properties of bioactive glasses for use in air abrasion

    International Nuclear Information System (INIS)

    Farooq, Imran; Brauer, Delia S; Hill, Robert G; Tylkowski, Maxi; Müller, Steffen; Janicki, Tomasz

    2013-01-01

    Air abrasion is used in minimally invasive dentistry for preparing cavities, while removing no or little sound dentine or enamel, and the use of bioactive glass (rather than alumina) as an abrasive could aid in tooth remineralization. Melt-derived bioactive glasses (SiO 2 –P 2 O 5 –CaO–CaF 2 –Na 2 O) with low sodium content (0 to 10 mol% Na 2 O in exchange for CaO) for increased hardness, high phosphate content for high bioactivity and fluoride content for release of fluoride and formation of fluorapatite were produced, and particles between 38 and 80 µm in size were used for cutting soda-lime silicate glass microscope slides and human enamel. Vickers hardness increased with decreasing Na 2 O content, owing to a more compact silicate network in low sodium content glasses, resulting in shorter cutting times. Cutting times using bioactive glass were significantly longer than using the alumina control (29 µm) when tested on microscope slides; however, glasses showed more comparable results when cutting human enamel. The bioactive glasses formed apatite in Tris buffer within 6 h, which was significantly faster than Bioglass® 45S5 (24 h), suggesting that the hardness of the glasses makes them suitable for air abrasion application, while their high bioactivity and fluoride content make them of interest for tooth remineralization. (paper)

  4. Influence of sodium content on the properties of bioactive glasses for use in air abrasion.

    Science.gov (United States)

    Farooq, Imran; Tylkowski, Maxi; Müller, Steffen; Janicki, Tomasz; Brauer, Delia S; Hill, Robert G

    2013-12-01

    Air abrasion is used in minimally invasive dentistry for preparing cavities, while removing no or little sound dentine or enamel, and the use of bioactive glass (rather than alumina) as an abrasive could aid in tooth remineralization. Melt-derived bioactive glasses (SiO2-P2O5-CaO-CaF2-Na2O) with low sodium content (0 to 10 mol% Na2O in exchange for CaO) for increased hardness, high phosphate content for high bioactivity and fluoride content for release of fluoride and formation of fluorapatite were produced, and particles between 38 and 80 µm in size were used for cutting soda-lime silicate glass microscope slides and human enamel. Vickers hardness increased with decreasing Na2O content, owing to a more compact silicate network in low sodium content glasses, resulting in shorter cutting times. Cutting times using bioactive glass were significantly longer than using the alumina control (29 µm) when tested on microscope slides; however, glasses showed more comparable results when cutting human enamel. The bioactive glasses formed apatite in Tris buffer within 6 h, which was significantly faster than Bioglass® 45S5 (24 h), suggesting that the hardness of the glasses makes them suitable for air abrasion application, while their high bioactivity and fluoride content make them of interest for tooth remineralization.

  5. Electron irradiation effect on bubble formation and growth in a sodium borosilicate glass

    International Nuclear Information System (INIS)

    Chen, X.; Birtcher, R. C.; Donnelly, S. E.

    2000-01-01

    In this study, the authors studied simultaneous and intermittent electron irradiation effects on bubble growth in a simple sodium borosilicate glass during Xe ion implantation at 200 C. Simultaneous electron irradiation increases the average bubble size in the glass. This enhanced diffusion is also shown by the migration of Xe from bubbles into the matrix when the sample is irradiated by an electron beam after the Xe implantation

  6. Characterization of Sm14 related components in different helminths by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blotting analysis

    Directory of Open Access Journals (Sweden)

    Nilton Thaumaturgo

    2002-10-01

    Full Text Available Sm14 was the first fatty acid-binding protein homologue identified in helminths. Thereafter, members of the same family were identified in several helminth species, with high aminoacid sequence homology between them. In addition, immune crossprotection was also reported against Fasciola hepatica infection, in animals previously immunized with the Schistosoma mansoni vaccine candidate, r-Sm14. In the present study, data on preliminary sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blotting analysis of nine different helminth extracts focusing the identification of Sm14 related proteins, is reported. Out of these, three extracts - Ascaris suum (males and females, Echinostoma paraensei, and Taenia saginata - presented components that comigrated with Sm14 in SDS-PAGE, and that were recognized by anti-rSm14 policlonal serum, in Western blotting tests.

  7. Determination of albumins by its quenching effect on the fluorescence of Tb{sup 3+}-oxolinic acid complex in presence of sodium dodecyl sulphate

    Energy Technology Data Exchange (ETDEWEB)

    Wu Xia [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Zheng Jinhua [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Guo Changying [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Yang Jinghe [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)]. E-mail: yjh@sdu.edu.cn; Ding Honghong [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Hu Zhiyong [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China); Li Chao [Key Laboratory of Colloid and Interface Chemistry (Shandong University), Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)

    2007-09-15

    It is found that the fluorescence intensity of Tb{sup 3+}-oxolinic acid (OA) complex can be greatly quenched by albumins in sodium dodecyl sulphate (SLS). Under optimum conditions, the quenched fluorescence intensity is in proportion to the concentration of proteins in the range of 5.0x10{sup -8}-1.0x10{sup -5} g ml{sup -1} for bovine serum albumin (BSA), 1.0x10{sup -7}-1.0x10{sup -5} g ml{sup -1} for human serum albumin (HSA) and 4.0x10{sup -7}-1.0x10{sup -5} g ml{sup -1} for egg albumin (EA). Their detection limits (S/N=3) are 2.1x10{sup -8}, 2.5x10{sup -8} and 5.0x10{sup -8} g ml{sup -1}, respectively. In addition, the interaction mechanism is also investigated.

  8. Determination of albumins by its quenching effect on the fluorescence of Tb3+-oxolinic acid complex in presence of sodium dodecyl sulphate

    International Nuclear Information System (INIS)

    Wu Xia; Zheng Jinhua; Guo Changying; Yang Jinghe; Ding Honghong; Hu Zhiyong; Li Chao

    2007-01-01

    It is found that the fluorescence intensity of Tb 3+ -oxolinic acid (OA) complex can be greatly quenched by albumins in sodium dodecyl sulphate (SLS). Under optimum conditions, the quenched fluorescence intensity is in proportion to the concentration of proteins in the range of 5.0x10 -8 -1.0x10 -5 g ml -1 for bovine serum albumin (BSA), 1.0x10 -7 -1.0x10 -5 g ml -1 for human serum albumin (HSA) and 4.0x10 -7 -1.0x10 -5 g ml -1 for egg albumin (EA). Their detection limits (S/N=3) are 2.1x10 -8 , 2.5x10 -8 and 5.0x10 -8 g ml -1 , respectively. In addition, the interaction mechanism is also investigated

  9. Molecular dynamics simulation of sodium aluminosilicate glass structures and glass surface-water reactions using the reactive force field (ReaxFF)

    Science.gov (United States)

    Dongol, R.; Wang, L.; Cormack, A. N.; Sundaram, S. K.

    2018-05-01

    Reactive potentials are increasingly used to study the properties of glasses and glass water reactions in a reactive molecular dynamics (MD) framework. In this study, we have simulated a ternary sodium aluminosilicate glass and investigated the initial stages of the glass surface-water reactions at 300 K using reactive force field (ReaxFF). On comparison of the simulated glass structures generated using ReaxFF and classical Buckingham potentials, our results show that the atomic density profiles calculated for the surface glass structures indicate a bond-angle distribution dependency. The atomic density profiles also show higher concentrations of non-bridging oxygens (NBOs) and sodium ions at the glass surface. Additionally, we present our results of formation of silanol species and the diffusion of water molecules at the glass surface using ReaxFF.

  10. Protective effect of Clostridium tyrobutyricum in acute dextran sodium sulphate-induced colitis: differential regulation of tumour necrosis factor-a and interleukin-18 in BALB/c and severe combined immunodeficiency mice

    NARCIS (Netherlands)

    Hudcovic, T.; Kolinska, J.; Klepetar, J.; Stepankova, R.; Rezanka, T.; Srutkova, D.; Schwarzer, M.; Erban, V.; Du, Z.; Wells, J.; Hrncir, T.; Tlaskalova-Hogenova, H.; Kozakova, H.

    2012-01-01

    One of the promising approaches in the therapy of ulcerative colitis is administration of butyrate, an energy source for colonocytes, into the lumen of the colon. This study investigates the effect of butyrate producing bacterium Clostridium tyrobutyricum on dextran sodium sulphate (DSS)-induced

  11. Reference values for urinary oxalate, calcium, citrate, uric acid, phosphate, magnesium, sulphate and sodium in biochemistry students at Universidad Nacional del Litoral, Argentina

    Directory of Open Access Journals (Sweden)

    Verónica Fernández

    2017-10-01

    Full Text Available Introduction: Urolithiasis (UL is a common disease whose incidence increased in the last quarter of the twentieth century. Metabolic evaluation is necessary for diagnosis, which requires the establishment of reference values (RV for the population in question. Objective: To determine the RV for calcium, oxalate, citrate, uric acid, phosphate, magnesium, sulphate and sodium in 24-hour urine belonging to students from the School of Biochemistry and Biological Sciences at Universidad Nacional del Litoral, province of Santa Fe, Argentina. Once RV were established, a frequency of alterations was determined and then compared with literature data. Methods: The NCCLSC28-A3 guideline (2008 was used. The study group included 69 students. The enzymatic colorimetric method, a Metrolab 1600 plus spectrophotometer and a DIESTRO ionselective electrode were also employed. Results: The RV found (95 % CI were the following: oxalate, 1.96-45.08; calcium, 20.65-250.74; citrate, 112.78-666.01; uric acid, 58.73-782.17; phosphate, 238.37-1051.44; magnesium, 28.7-146.67, all these values expressed as mg/24h; sulphate, 3.15-25.18 mmol/24h, and sodium, 42.81-285.3 mEq/24h. These findings emerged as well: hyperoxaluria, 3 %; hypercalciuria 12 %; hypocitraturia, 3 %; hyperuricosuria, 6 %; hyperphosphaturia, 6 %; hypomagnesuria, 6 %; hypernatriuria, 7 %, and hypersulphaturia, 0 %. When RV were compared, some analyte levels were similar and others showed a considerable difference. Conclusions: The diagnosis of UL through the study of metabolic changes is different according to the reference value used. Applying reference values established for other populations, including those of commercial kits manufacturers, may lead to a diagnosis which does not match the clinical condition of the patient.

  12. Spectral-luminescence properties of trivalent titanium in aluminum-sodium phosphate glass

    International Nuclear Information System (INIS)

    Sukhanov, S.B.; Batyaev, I.M.

    1992-01-01

    Since development of the first crystal laser, Al 2 O 3 crystals remain the most widely used in quantum electronics. In the present work, the aluminum-sodium phosphate glass, Al 2 O 3 -Na 2 O 3 -P 2 O 5 , was studied with different proportions of components. A luminescence medium is obtained based on phosphate glass doped by Ti 3+ ions with intense emission in the 700-900-nm spectral range. This glass is a promising lasing medium for tunable solid-state lasers. 12 refs., 2 figs

  13. 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.

  14. Structural and thermochemical properties of sodium magnesium phosphate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Oueslati Omrani, Refka [Université de Tunis El Manar, Faculté des Sciences de Tunis, Chemistry Department, LR01SE10 Applied Thermodynamics Laboratory, 2092 Tunis (Tunisia); Kaoutar, Abdeltif; El Jazouli, Abdelaziz [LCMS, URAC 17, Faculté des Sciences Ben M’Sik, UH2MC, Casablanca (Morocco); Krimi, Saida [LPCMI, Faculté des Sciences Aïn Chok, UH2C, Casablanca (Morocco); Khattech, Ismail, E-mail: ismail.khattech@fst.rnu.tn [Université de Tunis El Manar, Faculté des Sciences de Tunis, Chemistry Department, LR01SE10 Applied Thermodynamics Laboratory, 2092 Tunis (Tunisia); Jemal, Mohamed [Université de Tunis El Manar, Faculté des Sciences de Tunis, Chemistry Department, LR01SE10 Applied Thermodynamics Laboratory, 2092 Tunis (Tunisia); Videau, Jean-Jacques [ICMCB, Institut de Chimie de la matière condensée, Université de Bordeaux 1 (France); Couzi, Michel [Institut des Sciences Moléculaires, CNRS-Université de Bordeaux 1 (France)

    2015-05-25

    Highlights: • Phosphate glasses were prepared by met quenching technique. • Structural study is investigated using FTIR, Raman and {sup 31}PNMR spectroscopy. • A 4.5% weight of H{sub 3}PO{sub 4} solution has use for glass dissolution. • Dissolution is endothermic for lower MgO content and becomes exothermic when x rises. - Abstract: Ternary phosphate based glasses with the general formula (50−x/2)Na{sub 2}O–xMgO–(50−x/2)P{sub 2}O{sub 5} (0 ⩽ x ⩽ 42.8 mol%), where the O/P ratio was varied from 3 to 3.75, have been prepared using a conventional melt quenching technique. Samples were investigated by means of density measurements, Fourier-transformed infrared (FTIR), Raman and {sup 31}P solid state magic angle spinning nuclear magnetic resonance (MAS-NMR) spectroscopies, differential scanning calorimetry (DSC), inductively coupled plasma atomic emission spectroscopy (ICP/AES) analysis and calorimetric dissolution. The depolymerization of metaphosphate chains are described by the decrease of Q{sup 2} tetrahedral sites allowing the formation of pyrophosphate groups (Q{sup 1}) revealed by spectroscopic investigations. As a result, the increase of density and glass transition temperature when x rises. Calorimetric study shows that the dissolution phenomenon is endothermic for a lower MgO content and becomes exothermic when magnesium oxide is gradually incorporated, suggesting the disruption of phosphate chains with increasing O/P ratio.

  15. Magnetic susceptibility of sodium disilicate glasses containing PuO2

    International Nuclear Information System (INIS)

    Aldred, A.T.

    1979-01-01

    A solubility limit of approx. 6 mol % PuO 2 in sodium disilicate (Na 2 O.2SiO 2 ) glass has been determined. Magnetic susceptibility measurements on these glasses yield approximate Curie-Weiss behavior, in contrast to the temperature-independent susceptibility of crystalline PuO 2 . This result is interpreted to indicate that the local site symmetry around the Pu ion in the sodium disilicate glass is much different than in crystalline PuO 2 . The effective paramagnetic moments determined from the temperature dependence of the susceptibility are found to be consistent with calculated free-ion values based on the most likely 5f electron configurations

  16. Femtosecond laser-induced reduction in Eu-doped sodium borate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Ki-Soo [Department of Physics and Basic Science Research Institute, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)]. E-mail: kslim@chungbuk.ac.kr; Lee, Sunkyun [Department of Physics and Basic Science Research Institute, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Trinh, Minh-Tuan [Department of Physics and Basic Science Research Institute, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Kim, Suk-Ho [Department of Physics and Basic Science Research Institute, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Lee, Myeongkyu [Departent of Materials Science and Engineering, Yonsei University, 134 Shinchon-dong, Seoul 120-749 (Korea, Republic of); Hamilton, Douglas S. [Department of Physics, University of Connecticut, Storrs, CT 06269 (United States); Gibson, George N. [Department of Physics, University of Connecticut, Storrs, CT 06269 (United States)

    2007-01-15

    In this work, we report permanent reduction of Eu{sup 3+} to Eu{sup 2+} in sodium borate glasses by irradiation of near-infrared femtosecond laser. Glass composition of sodium borate was 85B{sub 2}O{sub 3}-15Na{sub 2}O. The glasses were doped with 0.05, 0.1, and 0.5 mol% Eu{sub 2}O{sub 3}. Absorption and fluorescence dynamics were studied to investigate valence state change of europium ions and the energy transfer between Eu{sup 2+} and Eu{sup 3+} ions. As the femtosecond laser intensity or exposure time increases, the emission band at 400 nm becomes stronger. However, the photoreduction efficiency decreases as the dopant concentration increases. We discuss the photoreduction mechanism under multiphoton absorption.

  17. On the Elastic behavior of Sodium Borate Glasses

    Science.gov (United States)

    Vignarooban, K.; Boolchand, P.; Kerner, R.; Micoulaut, M.

    2010-03-01

    Alkali Borates are industrial glasses and their physical properties are of general interest. We have made a special effort to synthesize dry (Na2O)x(B2O3)100-x glasses over a wide composition range, 0 modulated-DSC, Raman scattering, FTIR, and molar volume experiments. The enthalpy of relaxation at Tg shows a global minimum in the 20% < x < 40% range, which we identify with the rigid but stress-free Intermediate Phase (IP). The Boroxyl ring vibrational mode near 808 cm-1 in B2O3, steadily softens by about 4 cm-1 as the soda content increases to about 20%. A vibrational mode of mixed ringsfootnotetextKamitsos et al., Jour. Mol. Struct 247, 1 (1996). (containing 3-fold and 4-fold B) is also observed near 775 cm-1 at low x, and it also steadily softens by nearly 10 cm-1 as x increases in the 20% < x < 40% soda range (IP). We are examining the underlying optical elasticity power-laws to ascertain the nature of the elastic phases. IR reflectance experiments provide the 4-fold coordinated B fraction to increase from 0.17 near x = 20% to 0.44 near x = 40% in broad agreement with NMR results. Evolution of physical properties of these glasses with soda content will be reviewed.

  18. Red light emission from europium doped zinc sodium bismuth borate glasses

    Science.gov (United States)

    Hegde, Vinod; Viswanath, C. S. Dwaraka; Upadhyaya, Vyasa; Mahato, K. K.; Kamath, Sudha D.

    2017-12-01

    Zinc sodium bismuth borate (ZNBB) glasses doped with different concentrations of europium were prepared by conventional melt quenching method and characterized through the measurements of density, refractive index, X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectra, optical absorption, luminescence and radiative lifetimes. FTIR spectra showed seven characteristic peaks of bismuth and borate functional groups in the range of 400-1600 cm-1. The optical band gap and bonding parameters have been calculated from absorption spectra. Photoluminescence spectra recorded in the visible region with 394 nm excitation are used to calculate the Judd-Ofelt (JO) intensity parameters (Ω2 and Ω4). The JO intensity parameters have been used to calculate the radiative parameters such as branching ratio (β), stimulated emission cross-section (σse), transition probability (A) for the fluorescent level of 5D0→7F2. Decay rates through single exponential are used to calculate the lifetime (τm) of the meta-stable state 5D0 of (Eu3+ ion) these glasses. The radiative parameters measured for all these glasses show 0.7 mol% europium doped zinc sodium bismuth borate glass 5D0→7F2 transition has the potential for red laser applications. The quality of the colour emitted by the present glasses are estimated quantitatively by CIE chromaticity coordinates, which confirms the suitability of these glasses as a red emitting material for field emission technologies and LEDs.

  19. Bacterial sulphate reduction and the development of alkalinity. I. Experiments with synthetic media

    Energy Technology Data Exchange (ETDEWEB)

    Abd-El-Malek, Y; Rizk, S G

    1963-01-01

    In liquid cultures of desulphovibrio desulphuricans the effects of the following on sulphate reduction were determined: The type of cation (ca++ or na+) attached to the sulphate ion; the presence of calcium carbonate alone and with sodium chloride; the concentration of sodium sulphate, sodium lactate and sodium chloride; and the initial pH. The titratable alkalinity formed as a result of sulphate reduction was found to be quantitatively related to the sulphate reduced, and apparently unaffected by strain variation or energy source.

  20. 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.

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

    Science.gov (United States)

    Kilymis, D A; Delaye, J-M

    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 SiO2 content of the glass, which promotes densification due to the open structure of SiO4 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.

  2. Optical and spectroscopic properties of neodymium doped cadmium-sodium borate glasses

    Science.gov (United States)

    Mohan, Shaweta; Thind, Kulwant Singh

    2017-10-01

    Neodymium doped cadmium sodium borate glasses having composition xCdO-(40-x) Na2CO3-59.5H3BO3-0.5Nd2O3; x = 10, 20 and 30 mol% were prepared by conventional melt-quenching technique. X-ray diffraction studies confirmed the amorphous nature of the prepared glasses. Conventional methods were used to determine the physical properties such as density, molar volume, refractive index, and rare earth ion concentration. The Judd-Ofelt theory was applied on the optical absorption spectra of the glasses to evaluate the three phenomenological intensity parameters Ω2, Ω4 and Ω6. The calculated intensity parameters were further used to predict the radiative transition probability (A), radiative lifetime (τR) and branching ratio (βR) for the various fluorescent levels of Nd3+ ion in the prepared glass series. The effect of the compositional changes on the spectroscopic characteristics of Nd3+ ions have been studied and reported. The value of Ω2 is found to decrease with the decrease in the sodium content and the corresponding increase in the cadmium content. This can be ascribed to the changes in the asymmetry of the ligand field at the rare earth ion site and the change in rare earth oxygen (RE-O) covalency. Florescence spectra has been used to determine the peak wavelength (λp), effective line widths (Δλeff) and stimulated emission cross-section (σp) for the 4F3/2 → 4I9/2,4I11/2,4I13/2 transitions of the Nd3+ ion. The reasonably higher values of branching ratios and stimulated emission cross-section for the prepared glasses points towards the efficacy of these glasses as laser host materials. However, the glass with more sodium content is found to show better lasing properties.

  3. STUDY OF POLYMORPHISM OF BOROVANADATE GLASS OF SODIUM BY RAMAN SPECTROSCOPY LOW FREQUENCIES

    Directory of Open Access Journals (Sweden)

    M. K. Rabia

    2015-07-01

    Full Text Available Sodium tetraborate (100 – x(Na2B4O7.10H2O­­ ­­­­­– xV2O5, (x = 0 to 20 mole % has been elaborated by splat cooling technique. Raman Measurements on the doped and non polish samples reveal the presence of the of α-NaVO3 crystal on the superficial layer. After polishing, Raman spectra characteristic of glasses are obtained with two main bands located at 555 and 1097 cm-1 in the undoped glass and four bands at 241, 381, 776 and 938 cm-1 for the vanadium oxyde doped glasses. The volume devitrification of these glasses occurs at 750° C and the β-NaVO3 crystalline phase is identified by Raman scattering.

  4. Laser and thermal bleaching of colour centres in sodium borate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Bukharaev, A A; Yafaev, N R [AN SSSR, Kazan. Fiziko-Tekhnicheskij Inst.

    1978-12-01

    The maximum of the additional absorption band in ..gamma..- or UV-irradiated sodium borate glasses shifts to higher energy when the low-energy side of the band is bleached by a helium-neon laser, ..lambda.. = 632.8 nm. Simultaneously the half-width of the additional absorption band decreases. This phenomenon is associated with the fact that because of structural disorder of glasses there is a distribution of ground-state energies of trapped electrons forming the light-sensitive absorption band. The distribution interval of the activation energy for trapped electrons is estimated using the decomposition of the initial thermal bleaching curves into components. For UV irradiated glasses it is aproximately 0.24 eV, and for ..gamma..-irradiated glasses only 0.12 eV. These values correlate with the relative shift maximum of the absorption band at laser bleaching.

  5. A Novel Method for Detection of Glycoproteins on Sodium Dodecyl Sulphate Polyacrylamide Gel Using Radio-Iodinated Tyrosine

    DEFF Research Database (Denmark)

    Nalla, Amarnadh; Draz, Hossam M.; Dole, Anita

    2009-01-01

    The aim of this study is to develop a novel method for detection of glycoproteins on polyacrylamide gel. In this method, radio-iodinated-tyrosine (125I-tyrosine) was conjugated to glycoprotein by schiff's base mechanism on the sodium dodecyl sulfate- polyacrylamide gel. Ovalbumin and Concanavalin...... of glycoproteins using 125I-tyrosine selectively detected ovalbumin. Present results showed that MPD enhanced glycoprotein detection method can be used as a sensitive tool for the detection of glycoproteins on polyacrylamide gel...

  6. Influence of fining agents on glass melting: A review, Part 2

    Czech Academy of Sciences Publication Activity Database

    Hujová, Miroslava; Vernerová, Miroslava

    2017-01-01

    Roč. 61, č. 3 (2017), s. 202-208 ISSN 0862-5468 Institutional support: RVO:67985891 Keywords : glass melting * sodium sulphate * chemical reactions * gas evolution * dissolution * fining * bubble nucleation * foaming Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass OBOR OECD: Ceramics Impact factor: 0.439, year: 2016

  7. Influence of fining agents on glass melting: A review, Part 1

    Czech Academy of Sciences Publication Activity Database

    Hujová, Miroslava; Vernerová, Miroslava

    2017-01-01

    Roč. 61, č. 2 (2017), s. 119-126 ISSN 0862-5468 Institutional support: RVO:67985891 Keywords : glass melting * sodium sulphate * chemical reactions * gas evolution * dissolution * fining * bubble nucleation * foaming Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass OBOR OECD: Ceramics Impact factor: 0.439, year: 2016

  8. Laser- and gamma-induced transformations of optical spectra of indium-doped sodium borate glass

    CERN Document Server

    Kopyshinsky, O V; Zelensky, S E; Danilchenko, B A; Shakhov, O P

    2003-01-01

    The optical absorption and luminescence properties of indium-doped sodium borate glass irradiated by gamma-rays and by powerful UV lasers within the impurity-related absorption band are investigated experimentally. It is demonstrated that both the laser- and gamma-irradiation cause similar transformations of optical spectra in the UV and visible regions. The changes of the spectra observed are described with the use of a model which includes three types of impurity centres formed by differently charged indium ions.

  9. Dextran sulphate crowding and sodium deoxycholate lysis of primary breast fibroblast cells achieve extracellular matrix deposition and decellularization for breast cancer stem cell culture

    Directory of Open Access Journals (Sweden)

    Aroem Naruni

    2016-01-01

    .Extracellular matrix provides tissue integrity, acts as a native scaffold for cell attachment and interaction and alsoserves as reservoir for growth factors. The aim of this experiment w asto achieve the deposition and decellularizationof ECM.Methods: Cells crowder have been developed to increase ECM deposit in the primary breast fibroblast cells layerobtained from isolation of single cell from breast mammoplasty specimen. Five hundred kDa dextran was addedinto DMEM medium containing 0.5% fetal bovine serum (FBS and 100 μm of L-ascorbic acid 2-phosphate. Afterseven days, cells were lysed by sodium deoxycholate (DOC. Results were observed in a fluorescence microscope.Results: Extracellular matrix deposition and decellularization of primary breast fibroblast cells were detected byusing extracellular matrix protein, fibronectin via rabbit anti human fibronectin and anti-rabbit IgG conjugated withAlexa Fluor 488.Conclusion: Dextran sulphate increased extracellular matrix deposit in primary breast fibroblast cell layer and thetreatment with sodium deoxycolate lysed cells resulted in extracellular matrix decellularization. (Health ScienceJournal of Indonesia 2015;6:43-7Keywords: extracellular matrix, breast cancer stem cell, breast fibroblast cell

  10. Thermodynamic solution properties of pefloxacin mesylate and its interactions with organized assemblies of anionic surfactant, sodium dodecyl sulphate

    International Nuclear Information System (INIS)

    Usman, Muhammad; Rashid, Muhammad Abid; Mansha, Asim; Siddiq, Mohammad

    2013-01-01

    Graphical abstract: - Highlights: • Free energy of adsorption is more negative than free energy of micellization. • Micellization becomes more spontaneous at high temperature. • There is strong interaction between PFM and SDS. - Abstract: This manuscript reports the physicochemical behavior of antibiotic amphiphilic drug pefloxacin mesylate (PFM) and its interaction with anionic surfactant, sodium dodecyl sulfate (SDS). The data of surface tension and electrical conductivity are helpful to detect the CMC as well as to calculate surface parameters, i.e. surface pressure, π, surface excess concentration, Γ, area per molecule of drug and standard Gibbs free energy of adsorption, ΔG ads and thermodynamic parameters like standard free energy of micellization, ΔG m , standard enthalpy of micellization, ΔH m and standard entropy of micellization, ΔS m . The interaction of this drug with anionic surfactant, sodium dodecyl sulfate (SDS) was studied by electrical conductivity and UV/visible spectroscopy. This enabled us to compute the values of partition coefficient (K x ), free energy of partition, ΔG p , binding constant, K b , free energy of binding, ΔG b , number of drug molecules per micelle, n, and thermodynamic parameters of drug–surfactant interaction

  11. Protective effects of ethanol extract from Portulaca oleracea L on dextran sulphate sodium-induced mice ulcerative colitis involving anti-inflammatory and antioxidant

    Science.gov (United States)

    Yang, Xiaohang; Yan, Yongmei; Li, Jiankang; Tang, Zhishu; Sun, Jing; Zhang, Huan; Hao, Siyang; Wen, Aidong; Liu, Li

    2016-01-01

    Portulaca oleracea L., (POL) is one of commonly used medicine-food herbs and has a cosmopolitan distribution in many countries. Many studies showed that POL exhibited a wide range of pharmacological effects such as anti-inflammatory and liver complaints. In the clinical studies, POL was usually used for the treatment of UC disease and the clinical efficacy was well, but the mechanism and scientific intension was still unknown. In the present study, we studied the protective effects of the ethanol extract from POL on dextran sulphate sodium-induced UC in C57BL/6 mice model through oxidative stress and inflammatory pathway. The results demonstrated that the ethanol extract from POL could exhibit the effective protection for the DSS induced UC by increasing the colon length, decreasing body weight loss and the disease activity index score, inhibiting oxidative stress response through the MDA, NO, SOD activities, reducing the mRNA expressions of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) and the protein expressions of TNF-α and NF-kB p65. These results may prove that POL could be considered as a useful and effective botanical compound from the edible plant to be used in UC through the oxidative stress and inflammatory activities. PMID:27347321

  12. Studies on the rice seed (Oryza sativa) sensitivity to gama radiation, neutrons di-enthyl sulphate (DES) and sodium azide (SA)

    International Nuclear Information System (INIS)

    Guimaraes, E.P.

    1978-04-01

    Dry rice seeds of 'Dourado Precoce' variety were treated with gama-rays, thermal and fast neutrons, di-ethyl sulphate (DES) and sodium azide (SA). Biologial effects on survival, seedling height, plant fertility and chlorophy 11 mutation frequency were studied in the M 1 generation. The data obtained were analysed by 'independent test'. Survival was not affected by increased gama ray dosage, but by increased DES and SA dosages, as well as by SA treatments with increased solution acidity for seeds pretreated in distilled water. Seedling height was decreased with the increase of gama-ray dosage, DES concentration. SA acidity and concentration. Plant fertility was reduced drastically with higher gama-ray and neutron dosages and with high SA acidity and concentrations. The maximum chlorophy 11 mutation frequency was obtained in the SA treatment. Seeds pretreated with distilled water showed larger physiological damages in the SA treatments and higher mutation frequencies. Regarding chlorophyll mutation frequency, thermal neutrons were more efficient than gama-rays. SA was the most efficient mutagen used . DES showed lower physiological damages in the M 1 plants, but did not induce mutations in the used conditions [pt

  13. Stress responses of duckweed (Lemna minor L.) and water velvet (Azolla filiculoides Lam.) to anionic surfactant sodium-dodecyl-sulphate (SDS).

    Science.gov (United States)

    Forni, C; Braglia, R; Harren, F J M; Cristescu, S M

    2012-04-01

    Surfactants are used for several purposes and recently they have attracted the attention for their ability to modify the behavior of other preexistent or co-disposed contaminants, although their use or discharge in wastewaters can represent a real or potential risk for the environment. Lemna minor L. and Azolla filiculoides Lam. are floating aquatic macrophytes, very effective in accumulating several pollutants including sodium dodecyl sulphate (SDS). In this work we evaluated the effects of SDS on these species by determining the stress ethylene production via laser-based trace gas detection, and the activities of enzymes involved in stress response, such as guaiacol peroxidase (G-POD), phenylalanine ammonia-lyase (PAL) and polyphenol-oxidase (PPO). Phenolics content was also determined. The macrophytes were treated with different concentrations of SDS for one week. SDS affected duckweed enzymatic activities and phenol content. While in the fern phenolics amount, PAL, G-POD and PPO activities were not affected by SDS except for 100 ppm SDS, the only concentration that was taken up and not completely degraded. Stress ethylene production was induced only in the fern treated with 50 and 100 ppm SDS. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Optical and physical properties of sodium lead barium borate glasses doped with praseodymium ion

    Science.gov (United States)

    Lenkennavar, Susheela K.; Madhu, A.; Eraiah, B.; Kokila, M. K.

    2018-05-01

    Praseodymium doped sodium lead barium borate glasses have been prepared using single step melt quenching technique. The XRD spectrum confirms amorphous nature of glasses. The optical absorbance studies were carried out on these glasses using PekinElemer Lambda-35 Uv-Vis spectrometer in the range of 200 -1100 nm. The optical direct band gap energies were found to be in the range of 3.62 eV to 3.69 eV and indirect band gap energies were found to be in the range of 3.57 eV to 3.62eV. The refractive indices were measured by using Abbe refractometer the values are in the range of 1.620 to 1.625.

  15. 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)

  16. 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

  17. Prevention of Chronic Experimental Colitis Induced by Dextran Sulphate Sodium (DSS in Mice Treated with FR91

    Directory of Open Access Journals (Sweden)

    Valter R. M. Lombardi

    2012-01-01

    Full Text Available One of the main treatments currently used in humans to fight cancer is chemotherapy. A huge number of compounds with antitumor activity are present in nature, and many of their derivatives are produced by microorganisms. However, the search for new drugs still represents a main objective for cancer therapy, due to drug toxicity and resistance to multiple chemotherapeutic drugs. In animal models, a short-time oral administration of dextran sulfate sodium (DSS induces colitis, which exhibits several clinical and histological features similar to ulcerative colitis (UC. However, the pathogenic factors responsible for DSS-induced colitis and the subsequent colon cancer also remain unclear. We investigated the effect of FR91, a standardized lysate of microbial cells belonging to the Bacillus genus which has been previously shown to have significant immunomodulatory effects, against intestinal inflammation. Colitis was induced in mice during 5 weeks by oral administration 2% (DSS. Morphological changes in the colonic mucosa were evaluated by hematoxylin-eosin staining and immunohistochemistry methods. Adenocarcinoma and cryptal cells of the dysplastic epithelium showed cathenin-β, MLH1, APC, and p53 expression, together with increased production of IFN-γ. In our model, the optimal dose response was the 20% FR91 concentration, where no histological alterations or mild DSS-induced lesions were observed. These results indicate that FR91 may act as a chemopreventive agent against inflammation in mice DSS-induced colitis.

  18. Thermal, optical and structural properties of Dy3+ doped sodium aluminophosphate glasses

    Science.gov (United States)

    Kaur, Manpreet; Singh, Anupinder; Thakur, Vanita; Singh, Lakhwant

    2016-03-01

    Trivalent Dysprosium doped sodium aluminophosphate glasses with composition 50P2O5-10Al2O3-(20-x)Na2O-20CaO-xDy2O3 (x varying from 0 to 5 mol%) were prepared by melt quench technique. The density of the prepared samples was measured using Archimedes principle and various physical properties like molar volume, rare earth ion concentration, polaron radius, inter nuclear distance and field strength were calculated using different formulae. The differential scanning calorimetry (DSC) was carried out to study the thermal stability of prepared glasses. The UV Visible absorption spectra of the dysprosium doped glasses were found to be comprised of ten absorption bands which correspond to transitions from ground state 6H15/2 to various excited states. The indirect optical band gap energy of the samples was calculated by Tauc's plot and the optical energy was found to be attenuated with Dy3+ ions. The photoluminescence spectrum revealed that Dy3+ doped aluminophosphate glasses have strong emission bands in the visible region. A blue emission band centred at 486 nm, a bright yellow band centred at 575 nm and a weak red band centred at 668 nm were observed in the emission spectrum due to excitation at 352 nm wavelength. Both FTIR and Raman spectra assert slight structural changes induced in the host glass network with Dy3+ ions.

  19. Peculiarities of the diffusion of silver and sodium ions in phosphate glasses with a high content of sodium oxide

    International Nuclear Information System (INIS)

    Syutkin, V.M.; Tolkatchev, V.A.

    1996-01-01

    The phosphate glasses with a high content of alkali metal ions are good ionic conductors. Despite active studies, the mechanism of ion diffusion is not so far clear. The present work discusses the characteristics of ion diffusion in phosphate glasses with a high content of sodium oxide. An effective method to study ion transport is the investigation of relaxation processes the kinetics of which depends on ion diffusion. We use the data for two types of relaxation processes the kinetics of which is determined by ion diffusion. This is the conductivity relaxation due to sodium (host) ions and the decay of radiation-induced centers controlled by silver (guest) ion diffusion. Both of the processes being actually the first-order processes display a nonexponential kinetic behavior. The relaxation law can be interpreted either as the inherently nonexponential function or as the weighted sum of exponential decay functions with a distribution of relaxation times. It has been demonstrated that on the molecular level the relaxation function should be interpreted in the frame of the scheme of parallel first-order processes. This fact allows one to formulate a number of features of ion diffusion: (i) the mean square displacement of ions does not exceed several angstrom when transport becomes non-dispersive; (ii) the diffusion coefficient of ions is the function of coordinates. In this case, a characteristic distance at which D(r) noticeably varies is no less than a hundred of angstrom; (iii) the instantaneous concentration of mobile ions is well below the overall concentration ions

  20. Comparison of the Remineralizing Effects of Sodium Fluoride and Bioactive Glass Using Bioerodible Gel Systems

    Directory of Open Access Journals (Sweden)

    Attiguppe Ramashetty Prabhakar

    2009-12-01

    Full Text Available Background and aims. A carious lesion is the accumulation of numerous episodes of de- and remineralization, rather than a unidirectional demineralization process. Tooth destruction can be arrested or reversed by the frequent delivery of fluoride or calcium/phosphorous ions to the tooth surface. The present study compared and evaluated the remineralization potential of sodium fluoride and bioactive glass delivered through a bioerodible gel system. Materials and methods. Longitudinal sections of artificial carious lesions, created at the gingivofacial surface of 64 primary maxillary incisors were photographed under a polarized light microscope and quantified for demineralization. The sections were repositioned into the tooth form and randomly mounted in sets of four that simulated an arch form. The teeth were divided into 4 groups: 1 sodium fluoride films, 2 bioactive glass films, 3 control films placed interproximally and 4 nontreatment group. Following exposure to artificial saliva for 30 days, the lesions were again photographed and quantified as above. The recorded values were statistically analyzed using Student’s paired t-test for intragroup comparison, one-way ANOVA and Post-Hoc Tukey’s test for pairwise comparison. Results. The sodium fluoride and bioactive gel groups showed significant remineralization compared with the control groups (P < 0.001. Conclusion. Bioerodible gel films can be used to deliver remineralizing agents to enhance remineralization.

  1. Potassium/sodium ion exchange of sodium aluminosilicate and soda-lime glasses with potassium nitrate melts

    International Nuclear Information System (INIS)

    Richter, E.

    1983-08-01

    The alkali self-diffusion coefficients, the concentration-dependent interdiffusion coefficients, and the actual equilibrium constants of the ion exchange process were determinated for model glasses of the Na 2 O-Al 2 O 3 -SiO 2 type and the Na 2 O-CaO-SiO 2 type by nuclear techniques. The measured self-diffusion data and interdiffusion coefficients were used to estimate the stress profiles initiated by the K/Na exchange below the transformation temperature in the surface region. The activation volume of the sodium and potassium ions for diffusion through the surface zone stressed by ion exchange was determined. The disturbing influence of small concentrations of determined divalent cations in KNO 3 (especially Ca 2+ ) was investigated and thermodynamically described. Possibilities were demonstrated to remove these disturbances by anionic admixtures to the KNO 3 melt. Conclusions were drawn for the technical process of the chemical strengthening of glass by K/Na ion exchange at lower temperatures. (author)

  2. Andrographolide derivative CX-10 ameliorates dextran sulphate sodium-induced ulcerative colitis in mice: Involvement of NF-κB and MAPK signalling pathways.

    Science.gov (United States)

    Gao, Zhenfang; Yu, Cuicui; Liang, Haiyue; Wang, Xuekai; Liu, Yue; Li, Xin; Ji, Kai; Xu, Hui; Yang, Mingyan; Liu, Ke; Qi, Dong; Fan, Huaying

    2018-04-01

    Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD), which is characterized by chronic intestinal inflammation and leads to an increased risk of colon cancer. There are many studies using phyto-ingredients as a novel approach for the treatment of UC. The plant Andrographis paniculata (Acanthaceae) is a safe and edible vegetable that has been extensively adopted in traditional Chinese medicine for conditions involving inflammation, and the most active phytochemical agent is andrographolide. The andrographolide derivative 3,14,19-triacetyl andrographolide, which is known as CX-10 (a hemi chemical synthesized from andrographolide), has been found to possess strong anti-inflammatory properties. In the present study, we investigated the therapeutic potential of CX-10 as a complementary and alternative medicine against dextran sulphate sodium (DSS)-induced ulcerative colitis in mice. Our results revealed that CX-10 treatment reduced body weight loss, reduced colon length shortening, decreased colon weight, decreased the spleen index, decreased the disease activity index (DAI), and alleviated histological damage in the colon. The expression of TNF-α and IL-6 and the activity of myeloperoxidase (MPO) in colonic tissues were significantly reduced in CX-10 supplemented mice. It is noteworthy that the efficacy of 200 mg/kg of CX-10 was equivalent to that of the mesalazine positive control (200 mg/kg). Furthermore, western blot analysis revealed that CX-10 treatment reduced the expression of nuclear factor-κB (NF-κB) p65 and p-IκBα, increased the expression of IκBα and down-regulated the phosphorylation of p38 mitogen-activated protein kinase (MAPK), ERK and JNK. In conclusion, CX-10 treatment attenuated DSS-induced UC in mice through inhibiting the activation of NF-κB and MAPK pathways and reducing TNF-α and IL-6 levels, suggesting that CX-10 is a potential therapeutic drug for UC. Copyright © 2018. Published by Elsevier B.V.

  3. Unique gene expression and MR T2 relaxometry patterns define chronic murine dextran sodium sulphate colitis as a model for connective tissue changes in human Crohn's disease.

    Directory of Open Access Journals (Sweden)

    Christine Breynaert

    Full Text Available INTRODUCTION: Chronically relapsing inflammation, tissue remodeling and fibrosis are hallmarks of inflammatory bowel diseases. The aim of this study was to investigate changes in connective tissue in a chronic murine model resulting from repeated cycles of dextran sodium sulphate (DSS ingestion, to mimic the relapsing nature of the human disease. MATERIALS AND METHODS: C57BL/6 mice were exposed to DSS in drinking water for 1 week, followed by a recovery phase of 2 weeks. This cycle of exposure was repeated for up to 3 times (9 weeks in total. Colonic inflammation, fibrosis, extracellular matrix proteins and colonic gene expression were studied. In vivo MRI T 2 relaxometry was studied as a potential non-invasive imaging tool to evaluate bowel wall inflammation and fibrosis. RESULTS: Repeated cycles of DSS resulted in a relapsing and remitting disease course, which induced a chronic segmental, transmural colitis after 2 and 3 cycles of DSS with clear induction of fibrosis and remodeling of the muscular layer. Tenascin expression mirrored its expression in Crohn's colitis. Microarray data identified a gene expression profile different in chronic colitis from that in acute colitis. Additional recovery was associated with upregulation of unique genes, in particular keratins, pointing to activation of molecular pathways for healing and repair. In vivo MRI T2 relaxometry of the colon showed a clear shift towards higher T2 values in the acute stage and a gradual regression of T2 values with increasing cycles of DSS. CONCLUSIONS: Repeated cycles of DSS exposure induce fibrosis and connective tissue changes with typical features, as occurring in Crohn's disease. Colonic gene expression analysis revealed unique expression profiles in chronic colitis compared to acute colitis and after additional recovery, pointing to potential new targets to intervene with the induction of fibrosis. In vivo T2 relaxometry is a promising non-invasive assessment of

  4. Additive impairment of the barrier function and irritation by biogenic amines and sodium lauryl sulphate: a controlled in vivo tandem irritation study.

    Science.gov (United States)

    Fluhr, J W; Kelterer, D; Fuchs, S; Kaatz, M; Grieshaber, R; Kleesz, P; Elsner, P

    2005-01-01

    Biogenic amines are potential irritants e.g. in fish-, meat-, milk- and egg-processing professions like cooks, butchers and bakers. The aim of this study was to test the irritative and barrier-disrupting properties of the biogenic amines ammonium hydroxide (AM), dimethylamine (DMA) and trimethylamine (TMA). A repeated sequential irritation of 30 min twice per day was performed over a total of 4 days (tandem repeated irritation test) on the back of 20 healthy volunteers of both sexes with AM, DMA, TMA and sodium lauryl sulphate (SLS). The epidermal barrier function was assessed with a Tewameter TM 210, stratum corneum surface pH was measured with a Skin-pH-Meter 900, inflammation was assessed with a Chromameter CR-300 on the a* axis for redness and a visual score was recorded. All tested biogenic amines (AM, DMA and TMA) induced a barrier disruption and a pH increase paralleled with a 1-day-delayed onset of inflammatory signs. These effects were further enhanced and accelerated by a sequential application of SLS together with the biogenic amines, and inflammation occurred earlier than with the single compounds. Acetic acid (AA) in contrast did only show mild barrier disruption and no significant inflammatory signs. Our system allowed a ranking of the different compounds in their irritative potential in the tandem irritation with SLS: SLS > NaOH > TMA > AA > AM > DMA. The results are suggestive that in the food-processing industry the simultaneous contact with biogenic amines and harmful detergents like SLS should be minimized. Copyright 2005 S. Karger AG, Basel.

  5. High-resolution gel electrophoresis and sodium dodecyl sulphate-agarose gel electrophoresis on urine samples for qualitative analysis of proteinuria in dogs.

    Science.gov (United States)

    Giori, Luca; Tricomi, Flavia Marcella; Zatelli, Andrea; Roura, Xavier; Paltrinieri, Saverio

    2011-07-01

    The aims of the current study were to assess whether sodium dodecyl sulphate-agarose gel electrophoresis (SDS-AGE) and high-resolution electrophoresis (HRE) can identify dogs with a urinary protein-to-creatinine ratio (UPC ratio) >0.2 and whether HRE can provide preliminary information about the type of proteinuria, using SDS-AGE as a reference method. HRE and SDS-AGE were conducted on 87 urine samples classified according to the International Renal Interest Society as non-proteinuric (NP; UPC ratio: 0.51; 40/87). SDS-AGE and HRE were positive in 14 out of 32 and 3 out of 32 NP samples and in 52 out of 55 and 40 out of 55 samples with a UPC ratio >0.20, respectively. The concordance between HRE or SDS and UPC ratio was comparable (κ = 0.59; κ = 0.55). However, specificity (90%) and positive likelihood ratio (7.76) were higher for HRE than for SDS-AGE (56% and 2.16) while sensitivity was lower (73% vs. 94%). The analysis of HRE results revealed that a percentage of albumin >41.4% and an albumin/α(1)-globulin ratio (alb/α(1) ratio) >1.46 can identify samples classified by SDS-AGE as affected by glomerular proteinuria while a percentage of α(1)-globulin >40.8% and an alb/α(1) ratio HRE could misclassify samples with a UPC ratio higher or lower than 0.20. Therefore, UPC ratio must always be determined before conducting these tests. The percentage of albumin and α(1)-globulin or the alb/α(1) ratio determined by HRE can provide preliminary information about the origin of proteinuria.

  6. Dextran sulphate sodium colitis in C57BL/6J mice is alleviated by Lactococcus lactis and worsened by the neutralization of Tumor necrosis Factor α.

    Science.gov (United States)

    Berlec, Aleš; Perše, Martina; Ravnikar, Matjaž; Lunder, Mojca; Erman, Andreja; Cerar, Anton; Štrukelj, Borut

    2017-02-01

    TNFα has a well-established role in inflammatory bowel disease that affects the gastrointestinal tract and is usually manifested as Crohn's disease or ulcerative colitis. We have compared Lactococcus lactis NZ9000 displaying TNFα-binding affibody with control Lactococcus lactis and with anti-TNFα antibody infliximab for the treatment of mice with dextran sulphate sodium (DSS)-induced colitis. L. lactis NZ9000 alleviated the colitis severity one week after colitis induction with DSS, more effectively when administered in preventive fashion prior to, during and after DSS administration. TNFα-binding L. lactis was less effective than control L. lactis, particularly when TNFα-binding L. lactis was administered in preventive fashion. Similarly, an apparently detrimental effect of TNFα neutralization was observed in mice that were intraperitoneally administered anti-TNFα monoclonal antibody infliximab prior to colitis induction. The highest concentrations of tissue TNFα were observed in groups without DSS colitis that were treated either with TNFα-binding L. lactis or infliximab. To conclude, we have confirmed that L. lactis exerts a protective effect on DSS-induced colitis in mice. Contrary to expectations, but in line with some reports, the neutralization of TNFα aggravated disease symptoms in the acute phase of colitis and increased TNFα concentration in colon tissue of healthy mice. Nevertheless, we have demonstrated that oral administration of bacteria with surface displayed TNFα-binding affibody can interfere significantly with TNFα signaling and mimic the infliximab response in the given animal model of colitis. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Sulphate removal from uraniferous liquors

    International Nuclear Information System (INIS)

    Berger, B.

    1983-01-01

    A process for the recovery of uranium from liquor resulting from the attack of sulphur containing uraniferous ores by an alkaline solution of sodium carbonate and/or sodium bicarbonate is claimed. An ion exchange resin is used to separate the uranium from the solution of sodium carbonate and/or bicarbonate and sodium sulphate. The ion exchange resin is then eluted with a solution of ammonium carbonate and/or bicarbonate to provide an eluate containing ammonium uranyl tricarbonate, ammonium carbonate and/or bicarbonate and ammonium sulphate. The eluate is heated to boiling to convert the ammonium uranyl tricarbonate to ammonium uranate and/or diuranate. Ammonia, carbon dioxide and water vapor are released. The precipitated ammonium uranate and/or diuranate is separated from the remaining liquor and calcined to give uranium trioxide

  8. Oriented color centres being formed in anisotropic action of optical radiation on sodium-silicate glass

    International Nuclear Information System (INIS)

    Barinova, N.A.; Glebov, L.B.; Dokuchaev, V.G.; Savel'ev, V.L.

    1992-01-01

    A study was made of anisotropy of absorption of hole colour centres appearing in sodium-silicate glass due to anisotropic action of UV radiation. In case of such action in the field of long-wave edge of their fundamental absorption oriented hole colour centres occurs with maximum of absorption bands to 2.0, 2.8, 4.1 eV. Principal direction of hole colour centres orientation in this case coincides with orientation of ionized glass matrix centres. Orientation of such kind is connected with selective ionization of disorderedly oriented centres forming edge of fundamental absorption. Value of guided dichroism of colour centres absorption is determined by hole migration

  9. STRUCTURE FEATURES OF THE SODIUM-GERMANATE GLASSES DOPED WITH YTTERBIUM ERBIUM RETRIEVED FROM RAMAN SPECTROSCOPY

    Directory of Open Access Journals (Sweden)

    I. M. Sevastianova

    2016-09-01

    Full Text Available Subject of Research.The paper deals with study of Raman spectra and luminescence spectra in the visible region of the sodium-germanate glass: 49 GeO2 – 13 Na2O – 27 Yb2O3 – 11 La2O3 - 0,25 Er2O3 and presents research results. In addition, this glass is doped with 5 mol% of the following components MgO, BaO, Al2O3, PbO, Nb2O5, TiO2, SiO2, P2O5 in order to study the effect of these additives on the structure of the glassy matrix and the anti-Stokes luminescence spectra of erbium ions. Method. Raman scatteringspectra were recorded by Renishaw inVia Raman Microscope. Excitation source is a helium neon laser (λ= 633 nm with power equal to 50Wt. Anti-Stokes luminescence of erbium ions was registered in spectral region of 450–750 nm at room temperature (excitation laser wavelength is 975 nm, power is 1Wt. Main Results. It was shown that the structure of the initial glass does not change with the introduction of niobium as Nb2O5 in any coordination plays a role of network forming, building a single mixed grid with tetrahedrons [GeO4]. Introduction of the second glass former P2O5 leads to loosening germanate structure due to the appearance of the phosphate sublattice. This leads to a redistribution of the relative intensity of up-conversion luminescence bands with maxima at 540 and 670 nm compared with the initial glass. Introduction of additives PbO, MgO, Al2O3, TiO2 results in a multicenter structure. In case of titanium oxide addition it leads to a change in the relative intensities of the erbium luminescence.

  10. Thermo-physical and structural studies of sodium zinc borovanadate glasses in the region of high concentration of modifier oxides

    Energy Technology Data Exchange (ETDEWEB)

    Chethana, B.K. [Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012 (India); Reddy, C. Narayana [Maharani' s Science College for Women, Bangalore 560 001 (India); Rao, K.J., E-mail: kalyajrao@yahoo.co.in [Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012 (India)

    2012-07-15

    Highlights: ► Highly modified sodium zinc borovanadate glasses. ► Structural model for borovanadate glasses. ► Network forming tendency of ZnO in borovanadate glasses. ► Fragility can be limited to NBO concentration in borovanadate glasses. -- Abstract: This paper reports investigation of Na{sub 2}O and ZnO modified borovanadate glasses in the highly modified regime of compositions. These glasses have been prepared by microwave route. Ultraviolet (UV) and visible, infrared (IR), Magic Angle Spinning Nuclear Magnetic Resonance (MAS NMR) and Electron Paramagnetic Resonance (EPR) spectroscopies have been used to characterize the speciation in the glasses. Together with the variation of properties such as molar volume and glass transition temperatures, spectroscopic data indicate that at high levels of modification, ZnO tends to behave like network former. It is proposed that the observed variation of all the properties can be reasonably well understood with a structural model. The model considers that the modification and speciation in glasses are strongly determined by the hierarchy of group electronegativities. Further, it is proposed that the width of the transitions of glasses obtained under same condition reflects the fragility of the glasses. An empirical expression has been suggested to quantify fragility on the basis of width of the transition regions.

  11. Characteristics and environmental fate of the anionic surfactant sodium lauryl ether sulphate (SLES) used as the main component in foaming agents for mechanized tunnelling

    International Nuclear Information System (INIS)

    Barra Caracciolo, Anna; Cardoni, Martina; Pescatore, Tanita; Patrolecco, Luisa

    2017-01-01

    The anionic surfactant sodium lauryl ether sulphate (SLES) is the main component of most commercial products used for soil conditioning in the excavation industry, in particular as lubricants for mechanized tunnelling. Its use during the excavation processes can result in either the subsequent possible re-use of the huge amount of soil debris as by-products (e.g. land covering) or its discharge as waste. Currently, there are neither SLES soil threshold limits in European legislation, nor comprehensive studies on the environmental risk for soil ecosystems in these exposure scenarios. In this context, the present paper reviews the available data on the intrinsic characteristics of persistence and the ecotoxicological effects of the anionic surfactant SLES. Although SLES is generally reported to be biodegradable in standard tests, with degradation rates between 7 h and 30 days, depending on the initial conditions, data on its biodegradation in environmental studies are quite scarce. Consequently, assessing SLES biodegradation rates in field conditions is crucial for evaluating if in residual concentrations (typically in the range 40–500 mg/kg in excavated soils) it can or not be a potential hazard for terrestrial and water organisms. Laboratory ecotoxicological tests pointed out detrimental effects of SLES for aquatic organisms, while data on the terrestrial species are rather poor so far and further studies at the expected environmental concentrations are necessary. Finally, the review reports the main analytical methods available for detecting anionic surfactants in solid matrices and the future research needed to improve knowledge on the possible environmental risks posed by the use of SLES in foaming agents for mechanized tunnelling. - Highlights: • Tons of excavated soil containing SLES are reused posing an environmental risk. • SLES can have detrimental effects on aquatic organisms exposed in lab test. • There is a need to improve knowledge on SLES

  12. Synthesis and different optical properties of Gd2O3 doped sodium zinc tellurite glasses

    Science.gov (United States)

    Samanta, Buddhadev; Dutta, Dibakar; Ghosh, Subhankar

    2017-06-01

    A series of Gd2O3 doped sodium zinc tellurite [xGd2O3-(0.8-x) TeO2-0.1Na2O-0.1ZnO] glasses are prepared by the conventional melt quenching method and their optical properties have been studied. UV-vis spectrophotometric studies within the wavelength range from 230 nm-800 nm are carried out in the integrating sphere mode to study the effect of Gd2O3 doping on the optical band gap (Eg), refractive index (n), dielectric constant (εr) and susceptibility (χ). Other physical properties like molar volume, molar refraction, polarizability, metallization criterion, number density of rare-earth ions (N), polaron radius (rp), inter ionic distance (ri), molar cation polarizability (∑αi), number of oxide ions in chemical composition (NO2-), optical band gap based electronic oxide ion polarizability (αO2-) and optical basicity (Λ) of glass samples have been studied on the basis of UV-vis spectra and density profile of the different glasses.

  13. In vitro bioactivity of soda lime borate glasses with substituted SrO in sodium phosphate solution

    Directory of Open Access Journals (Sweden)

    Mohamed A. Marzouk

    2014-09-01

    Full Text Available Borate glasses with the basic composition 0.6B2O3·0.2Na2O·0.2CaO and SrO progressively substituting CaO were prepared and characterized for their bone-bonding ability. The obtained glasses were thermally treated and converted to their glass-ceramic derivatives. In this study, FTIR spectral analyses were done for the prepared glasses and glass-ceramics before and after immersion in a sodium phosphate solution for extended times. The appearance of two IR bands within the spectral range 550–680 cm-1 after immersion confirms the formation of hydroxyapatite. X-ray diffraction studies and scanning electron microscope analysis supported the obtained infrared spectroscopy results. The solubility test (measurements of the weight loss in aqueous sodium phosphate solution was conducted for measuring the dissolution of both glassy and crystalline derivatives to find out the role of SrO. The corrosion behaviour of the glasses and glass-ceramics indicate the increase of weight loss with the increase of SrO content. Different suggested proposals were introduced to explain this abnormal behaviour.

  14. Ionic conductivity of sodium silicate glasses grown within confined volume of mesoporous silica template

    Science.gov (United States)

    Chatterjee, Soumi; Saha, Shyamal Kumar; Chakravorty, Dipankar

    2018-04-01

    Nanodimensional sodium silicate glasses of composition 30Na2O.70SiO2 has been prepared within the pores of 5.5 nm of mesoporous silica as a template using the surfactant P123. The nanocomposite was characterized by X-ray diffraction, transmission electron microscope, and X-ray photoelectron spectroscopy. Electrical conductivity of the sample was studied by ac impedance spectroscopy. The activation energy for ionic conduction was found to be 0.13 eV with dc conductivity at room temperature of 10-6 S-cm-1. This is attributed to the creation of oxygen ion vacancies at the interface of mesoporous silica and nanoglass arising out of the presence of Si2+ species in the system. These nanocomposites are expected to be useful for applications in sodiumion battery for storage of renewable energy.

  15. Corrosion of K-3 glass-contact refractory in sodium-rich aluminosilicate melts

    International Nuclear Information System (INIS)

    Lu, X.D.; Gan, H.; Buechele, A.C.; Pegg, I.L.

    1999-01-01

    The corrosion of the glass-contact refractory Monofrax K-3 in two sodium-rich aluminosilicate melts has been studied at 1,208 and 1,283 C using a modified ASTM procedure with constant agitation of the melt by air bubbling. The results for the monolithic refractory indicate a fast initial stage involving phase dissolution and transformation and a later passivated stage in which the surface of the refractory has been substantially modified. The composition of the stable spinel phase in the altered layer on monolithic coupons of K-3 is almost identical to the equilibrium composition bracketed by the dissolution of powdered K-3 into under-saturated melts on the other. The temperature and melt shear viscosity were found to have significant effects on the rates of K-3 dissolution and transformation

  16. Effect of Sodium bicarbonate on Fire behaviour of tilled E- Glass Reinforced Epoxy Composites

    Science.gov (United States)

    Girish, S.; Devendra, K.; Bharath, K. N.

    2016-09-01

    Composites such as fibre reinforced polymers give us the good mechanical properties, but their fire behaviour is not appreciable and needs to be improved. In this work, E- glass fiber is used as a reinforcement material and Epoxy resin is used as a matrix with particulate sodium bi-carbonate (NaHCO3) is used as additive. The hand lay-up technique is adopted for the development of composites by varying percentage of additive. All the tests were conducted according to ASTM standards to study the Fire behaviour of the developed composites. The different fire properties like Ignition time, mass loss rate and flame propagation rate of Fiber Reinforced Polymers (FRP) with NaHCO3 are compared with neat FRPs. It is found that the ignition time increases as the percentage of additive is increased.

  17. 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.

  18. Study on sodium water glass-based anti-reflective film and its application in dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Q.Z. [Key Laboratory of Renewable Energy, Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Shi, J.F., E-mail: shijf@ms.giec.ac.cn [Key Laboratory of Renewable Energy, Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510000 (China); Wang, L.L.; Li, Y.J.; Zhong, L.W. [Key Laboratory of Renewable Energy, Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510000 (China); Xu, G., E-mail: xugang@ms.giec.ac.cn [Key Laboratory of Renewable Energy, Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510000 (China)

    2016-07-01

    In this paper, anti-reflective (AR) films are prepared from sodium water glass with a simple dip-coating method. The effects of SiO{sub 2}/Na{sub 2}O molar ratio, concentration of water glass, and withdrawal speed on the anti-reflection performance of the AR films are systematically studied. The optimized AR film is further applied in dye-sensitized solar cells (DSCs). The optical properties and surface morphology of AR films are analyzed by ultraviolet-visible spectrophotometer, scanning electron microscope, and atomic force microscope. Transmittance of the glass coated with sodium water glass-based AR film is increased by 3.2% when the SiO{sub 2}/Na{sub 2}O molar ratio, concentration, and withdrawal speed equal to 3.8, 5 wt%, and 80 mm/min, respectively. Under this condition, the thickness of the AR film is 127 nm and the AR film has obvious porous structure. In addition, the power conversion efficiency of DSC coated by AR film is increased from 7.92% to 8.24%, compared with the DSC without AR film. - Highlights: • Anti-reflective films are prepared from sodium water glass. • Transmittance of anti-reflective film is increased by 3.2%. • Efficiency of dye-sensitized cell is improved by anti-reflective film.

  19. Study on sodium water glass-based anti-reflective film and its application in dye-sensitized solar cells

    International Nuclear Information System (INIS)

    Huang, Q.Z.; Shi, J.F.; Wang, L.L.; Li, Y.J.; Zhong, L.W.; Xu, G.

    2016-01-01

    In this paper, anti-reflective (AR) films are prepared from sodium water glass with a simple dip-coating method. The effects of SiO_2/Na_2O molar ratio, concentration of water glass, and withdrawal speed on the anti-reflection performance of the AR films are systematically studied. The optimized AR film is further applied in dye-sensitized solar cells (DSCs). The optical properties and surface morphology of AR films are analyzed by ultraviolet-visible spectrophotometer, scanning electron microscope, and atomic force microscope. Transmittance of the glass coated with sodium water glass-based AR film is increased by 3.2% when the SiO_2/Na_2O molar ratio, concentration, and withdrawal speed equal to 3.8, 5 wt%, and 80 mm/min, respectively. Under this condition, the thickness of the AR film is 127 nm and the AR film has obvious porous structure. In addition, the power conversion efficiency of DSC coated by AR film is increased from 7.92% to 8.24%, compared with the DSC without AR film. - Highlights: • Anti-reflective films are prepared from sodium water glass. • Transmittance of anti-reflective film is increased by 3.2%. • Efficiency of dye-sensitized cell is improved by anti-reflective film.

  20. Thermal lens and interferometric method for glass transition and thermo physical properties measurements in Nd2O3 doped sodium zincborate glass.

    Science.gov (United States)

    Astrath, N G C; Steimacher, A; Rohling, J H; Medina, A N; Bento, A C; Baesso, M L; Jacinto, C; Catunda, T; Lima, S M; Karthikeyan, B

    2008-12-22

    In this work the time resolved thermal lens method is combined with interferometric technique, the thermal relaxation calorimetry, photoluminescence and lifetime measurements to determine the thermo physical properties of Nd(2)O(3) doped sodium zincborate glass as a function of temperature up to the glass transition region. Thermal diffusivity, thermal conductivity, fluorescence quantum efficiency, linear thermal expansion coefficient and thermal coefficient of electronic polarizability were determined. In conclusion, the results showed the ability of thermal lens and interferometric methods to perform measurements very close to the phase transition region. These techniques provide absolute values for the measured physical quantities and are advantageous when low scan rates are required.

  1. A 125Te and 23Na NMR investigation of the structure and crystallisation of sodium tellurite glasses.

    Science.gov (United States)

    Holland, D; Bailey, J; Ward, G; Turner, B; Tierney, P; Dupree, R

    2005-01-01

    125Te static nuclear magnetic resonance (NMR) and 23Na and 125Te magic angle spinning (MAS) NMR have been used, in conjunction with X-ray diffraction, to examine the structure and crystallisation behaviour of glasses of composition xNa2O.(1-x)TeO2 (0.075 x 0.4). The MAS NMR 23Na spectra from the glasses are broad and featureless but shift by approximately +5 ppm with increased x, i.e. as the system becomes more ionic. The static 125Te NMR spectra show an increase in axial symmetry with increasing x, indicating a shift from predominantly [TeO4] to [TeO3] structural units. The 23Na and 125Te spectra from the crystallised samples have been fitted to obtain information on the sites in the metastable crystal phases, which are the first to form on heating and which are therefore more closely related to the glass structure than thermodynamically stable crystal phases. New sodium tellurite phases are reported, including a sodium stabilised, face centred cubic phase related to delta-TeO2; a metastable form of Na2Te4O9 containing 3 sodium and 4 tellurium sites; and a metastable form of Na2Te2O5 containing 2 sodium sites. There is evidence of oxidation of TeIV to TeVI occurring in glasses with high values of x and, at x=0.40 and 0.50 (outside the glass forming range), some sodium metatellurate (Na2TeO4) is formed at the same time as sodium metatellurite (Na2TeO3). The 125Te shift is very sensitive to environment within the sodium tellurite system, covering more than 320 ppm, with anisotropies varying from 640 to 1540 ppm. The lack of features in the 125Te spectra of the glass phases, combined with the large shift range and high but variable anisotropy, means than it is not possible to obtain a unique fit to any presumed species present. Furthermore, the chemical shift anisotropy parameters for three of the four Te sites in the Na2Te4O9 phase are found to lie outside the range used for previous simulations of glass spectra.

  2. Effect of TeO2 on the elastic moduli of sodium borate glasses

    International Nuclear Information System (INIS)

    Saddeek, Y.B.; Abd El Latif, Lamia

    2004-01-01

    Sodium borate glass containing tellurite as Te x Na 2-2x B 4-4x O 7-5x with x=0, 0.05, 0.15, 0.25 and 0.35 have been prepared by rapid quenching. Ultrasonic velocity (both longitudinal and shear) measurements have been made using a transducer operated at the fundamental frequency of 4 MHz at room temperature. The density was measured by the conventional Archimedes method. The elastic moduli, the Debye temperature, Poisson's ratio, and the parameters derived from the Makishima-Mackenzie model and the bond compression model have been obtained as a function of TeO 2 content. The monotonic decrease in the velocities and the elastic moduli, and the increase in the ring diameter and the ratio K bc /K e as a function of TeO 2 modifier content reveals the loose packing structure, which is attributed to the increase in the molar volume and the reduction in the vibrations of the borate lattice. The observed results confirm that the addition of TeO 2 changes the rigid character of Na 2 B 4 O 7 to a matrix of ionic behaviour bonds (NBOs). This is due to the creation of more and more discontinuities and defects in the glasses, thus breaking down the borax structure

  3. 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.

  4. Infrared and x-ray photoelectron spectroscopic studies on sodium borosilicate glass interacted with thermally oxidized aluminides formed on alloy 690

    International Nuclear Information System (INIS)

    Yusufali, C.; Dutta, R.S.; Dey, G.K.; Kshirsagar, R.J.; Jagannath; Mishra, R.K.

    2012-01-01

    Thermally oxidized aluminides formed on Ni-Cr-Fe based superalloy 690 substrates were subjected to interaction with sodium borosilicate melt (used as matrices for immobilization of high-level radioactive liquid waste) at 1248 K for 192 hours. After the interaction, Fourier-transform infrared (FT-IR) spectroscopy analysis of glass samples indicated the incorporation of Al in the glass network. X-ray photoelectron spectroscopy (XPS) of glass specimens revealed modified glass structure. (author)

  5. Glass composition development for plasma processing of Hanford high sodium content low-level radioactive liquid waste

    International Nuclear Information System (INIS)

    Marra, J.C.

    1995-02-01

    To assess the acceptability of prospective compositions, response criteria based on durability, homogeneity, viscosity and volatility were defined. Response variables were weighted: durability 35%, homogeneity 25%, viscosity 25%, volatility 15%. A Plackett-Burman experimental design was used to define the first twelve glass formulations. Glass former additives included Al2O3, B2O3, CaO, Li2O, ZrO2 and SiO2. Lithia was added to facilitate fritting of the additives. The additives were normalized to silica content to ease experimental matrix definition and glass formulation. Preset high and low values of these ratios were determined for the initial twelve melts. Based on rankings of initial compositions, new formulations for testing were developed based on a simplex algorithm. Rating and ranking of subsequent compositions continued until no apparent improvement in glass quality was achieved in newly developed formulations. An optimized composition was determined by averaging the additive component values of the final best performing compositions. The glass former contents to form the optimized glass were: 16.1 wt % Al2O3, 12.3 wt % B2O3, 5.5 wt % CaO, 1.7 wt % Li2O, 3.3 wt % ZrO2, 61.1 wt % SiO2. An optimized composition resulted after only 25 trials despite studying six glass additives. A vitrification campaign was completed using a small-scale Joule heated melter. 80 lbs of glass was produced over 96 hours of continuous operation. Several salt compounds formed and deposited on melter components during the run and likely caused the failure of several pour chamber heaters. In an attempt to minimize sodium volatility, several low or no boron glasses were formulated. One composition containing no boron produced a homogeneous glass worthy of additional testing

  6. Effect of antimony-oxide on the shielding properties of some sodium-boro-silicate glasses.

    Science.gov (United States)

    Zoulfakar, A M; Abdel-Ghany, A M; Abou-Elnasr, T Z; Mostafa, A G; Salem, S M; El-Bahnaswy, H H

    2017-09-01

    Some sodium-silicate-boro-antimonate glasses having the molecular composition [(20) Na 2 O - (20) SiO 2 - (60-x) B 2 O 3 - (x) Sb 2 O 3 (where x takes the values 0, 5 … or 20)] have been prepared by the melt quenching method. The melting and annealing temperatures were 1500 and 650K respectively. The amorphous nature of the prepared samples was confirmed by using X-ray diffraction analysis. Both the experimental and empirical density and molar volume values showed gradual increase with increasing Sb 2 O 3 content. The empirical densities showed higher values than those obtained experimentally, while the empirical molar volume values appeared lower than those obtained experimentally, which confirm the amorphous nature and randomness character of the studied samples. The experimentally obtained shielding parameters were approximately coincident with those obtained theoretically by applying WinXCom program. At low gamma-ray energies (0.356 and 0.662MeV) Sb 2 O 3 has approximately no effect on the total Mass Attenuation Coefficient, while at high energies it acts to increase the total Mass Attenuation Coefficient gradually. The obtained Half Value Layer and Mean Free Path values showed gradual decrease as Sb 2 O 3 was gradually increased. Also, the Total Mass Attenuation Coefficient values obtained between about 0.8 and 3.0MeV gamma-ray energy showed a slight decrease, as gamma-ray photon energy increased. This may be due to the differences between the Attenuation Coefficients of both antimony and boron oxides at various gamma-ray photon energies. However, it can be stated that the addition of Sb 2 O 3 into sodium-boro-silicate glasses increases the gamma-ray Attenuation Coefficient and the best sample is that contains 20 mol% of Sb 2 O 3 , which is operating well at 0.356 and 0.662MeV gamma-ray. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Comparison of lead removal behaviors and generation of water-soluble sodium compounds in molten lead glass under a reductive atmosphere

    Science.gov (United States)

    Okada, Takashi; Nishimura, Fumihiro; Xu, Zhanglian; Yonezawa, Susumu

    2018-06-01

    We propose a method of reduction-melting at 1000 °C, using a sodium-based flux, to recover lead from cathode-ray tube funnel glass. To recover the added sodium from the treated glass, we combined a reduction-melting process with a subsequent annealing step at 700 °C, generating water-soluble sodium compounds in the molten glass. Using this combined process, this study compares lead removal behavior and the generation of water-soluble sodium compounds (sodium silicates and carbonates) in order to gain fundamental information to enhance the recovery of both lead and sodium. We find that lead removal increases with increasing melting time, whereas the generation efficiency of water-soluble sodium increases and decreases periodically. In particular, near 90% lead removal, the generation of water-soluble sodium compounds decreased sharply, increasing again with the prolongation of melting time. This is due to the different crystallization and phase separation efficiencies of water-soluble sodium in molten glass, whose structure continuously changes with lead removal. Previous studies used a melting time of 60 min in the processes. However, in this study, we observe that a melting time of 180 min enhances the water-soluble sodium generation efficiency.

  8. Sodium

    Science.gov (United States)

    Table salt is a combination of two minerals - sodium and chloride Your body needs some sodium to work properly. It helps with the function ... in your body. Your kidneys control how much sodium is in your body. If you have too ...

  9. 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.

  10. Sulphate in Pregnancy

    Directory of Open Access Journals (Sweden)

    Paul A. Dawson

    2015-03-01

    Full Text Available Sulphate is an obligate nutrient for healthy growth and development. Sulphate conjugation (sulphonation of proteoglycans maintains the structure and function of tissues. Sulphonation also regulates the bioactivity of steroids, thyroid hormone, bile acids, catecholamines and cholecystokinin, and detoxifies certain xenobiotics and pharmacological drugs. In adults and children, sulphate is obtained from the diet and from the intracellular metabolism of sulphur-containing amino acids. Dietary sulphate intake can vary greatly and is dependent on the type of food consumed and source of drinking water. Once ingested, sulphate is absorbed into circulation where its level is maintained at approximately 300 μmol/L, making sulphate the fourth most abundant anion in plasma. In pregnant women, circulating sulphate concentrations increase by twofold with levels peaking in late gestation. This increased sulphataemia, which is mediated by up-regulation of sulphate reabsorption in the maternal kidneys, provides a reservoir of sulphate to meet the gestational needs of the developing foetus. The foetus has negligible capacity to generate sulphate and thereby, is completely reliant on sulphate supply from the maternal circulation. Maternal hyposulphataemia leads to foetal sulphate deficiency and late gestational foetal death in mice. In humans, reduced sulphonation capacity has been linked to skeletal dysplasias, ranging from the mildest form, multiple epiphyseal dysplasia, to achondrogenesis Type IB, which results in severe skeletal underdevelopment and death in utero or shortly after birth. Despite being essential for numerous cellular and metabolic functions, the nutrient sulphate is largely unappreciated in clinical settings. This article will review the physiological roles and regulation of sulphate during pregnancy, with a particular focus on animal models of disturbed sulphate homeostasis and links to human pathophysiology.

  11. 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.

  12. 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.

  13. A relationship between leach rate of nuclear waste glass and residual amount of sodium on the glass surface

    International Nuclear Information System (INIS)

    Kamizono, Hiroshi; Banba, Tsunetaka

    1984-12-01

    Leach tests of simulated high-level waste glass were carried out in order to examine the quantitative relationship between the amount of elements on the sample surface and that in the leachate. An experimental equation was obtained expressing the relationship between the amount of Na on the sample surface and that in the leachate. This shows that it is possible in some cases to estimate the amount of Na in the leachate by measuring the amount of Na on the sample surface. One example of such an estimation was observed with the simulated high-level waste glass leached at 100 0 C in the presence of a backfill material. (author)

  14. LINEAR SOLVATION ENERGY RELATIONSHIPS FOR CHARACTERIZATION OF MLC SYSTEMS WITH SODIUM DODECYL SULPHATE MOBILE PHASES MODIFIED BY ALIPHATIC ALCOHOLS OR CARBOXYLIC ACIDS

    NARCIS (Netherlands)

    Markov, Vadym V.; Boichenko, Alexander P.; Loginova, Lidia P.

    2012-01-01

    The Linear Solvation Energy Relationships (LSER) have been successfully used for the modeling of partition and retention of the set of test compounds in different systems. The properties of micellar chromatographic systems with the mobile phases on the basis of sodium dodecylsulphate modified (ODS)

  15. Intrinsic strength of sodium borosilicate glass fibers by using a two-point bending technique

    International Nuclear Information System (INIS)

    Nishikubo, Y; Yoshida, S; Sugawara, T; Matsuoka, J

    2011-01-01

    Flaws existing on glass surface can be divided into two types, extrinsic and intrinsic. Although the extrinsic flaws are generated during processing and using, the intrinsic flaws are regarded as structural defects which result from thermal fluctuation. It is known that the extrinsic flaws determine glass strength, but effects of the intrinsic flaws on the glass strength are still unclear. Since it is considered that the averaged bond-strength and the intrinsic flaw would affect the intrinsic strength, the intrinsic strength of glass surely depends on the glass composition. In this study, the intrinsic failure strain of the glass fibers with the compositions of 20Na 2 O-40xB 2 O 3 -(80-40x)SiO 2 (mol%, x = 0, 0.5, 1.0, 1.5) were measured by using a two-point bending technique. The failure strength was estimated from the failure strain and Young's modulus of glass. It is elucidated that two-point bending strength of glass fiber decreases with increasing B 2 O 3 content in glass. The effects of the glass composition on the intrinsic strength are discussed in terms of elastic and inelastic deformation behaviors prior to fracture.

  16. 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)

  17. Sulphate in Liquid Nuclear Waste: from Production to Containment

    Energy Technology Data Exchange (ETDEWEB)

    Lenoir, M.; Grandjean, A.; Ledieu, A.; Dussossoy, J.L.; Cau Dit Coumes, C.; Barre, Y.; Tronche, E. [CEA Marcoule, DEN/DTCD/SECM/LDMC, Batiment 208 BP17171, Bagnols sur Ceze, 30207 (France)

    2009-06-15

    Nuclear industry produces a wide range of low and intermediate level liquid radioactive wastes which can include different radionuclides such as {sup 90}Sr. In La Hague reprocessing plant and in the nuclear research centers of CEA (Commissariat a l'Energie Atomique), the coprecipitation of strontium with barium sulphate is the technique used to treat selectively these contaminated streams with the best efficiency. After the decontamination process, low and intermediate level activity wastes incorporating significant quantities of sulphate are obtained. The challenge is to find a matrix easy to form and with a good chemical durability which is able to confine this kind of nuclear waste. The current process used to contain sulphate-rich nuclear wastes is bituminization. However, in order to improve properties of containment matrices and simplify the process, CEA has chosen to supervise researches on other materials such as cements or glasses. Indeed, cements are widely used for the immobilization of a variety of wastes (low and intermediate level wastes) and they may be an alternative matrix to bitumen. Even if Portland cement, which is extensively used in the nuclear industry, presents some disadvantages for the containment of sulphate-rich nuclear wastes (risk of swelling and cracking due to delayed ettringite formation), other cement systems, such as calcium sulfo-aluminate binders, may be valuable candidates. Another matrix to confine sulphate-rich waste could be the glass. One of the advantages of this material is that it could also immobilize sulphate containing high level nuclear waste which is present in some countries. This waste comes from the use of ferrous sulfamate as a reducing agent for the conversion of Pu{sup 4+} to Pu{sup 3+} in the partitioning stage of the actinides during reprocessing. Sulphate solubility in borosilicate glasses has already been studied in CEA at laboratory and pilot scales. At a pilot scale, low level liquid waste has been

  18. Unique crystallization behavior of sodium manganese pyrophosphate Na2MnP2O7 glass and its electrochemical properties

    Directory of Open Access Journals (Sweden)

    Morito Tanabe

    2017-06-01

    Full Text Available Crystallization behavior of Na2MnP2O7 precursor glass was examined. Layered type Na2MnP2O7 was formed at 461 °C for 3 h in N2 filled electric furnace. Irreversible phase change was confirmed from layered Na2MnP2O7 to β-Na2MnP2O7 over 600 °C. At 650 °C crystallized phase was completely changed to β-phase. By means of charge and discharge testing it is found that layered Na2MnP2O7 is also active as cathode in sodium ion batteries. We found glass-ceramics technology is one of the suitable process for the synthesis of layered Na2MnP2O7 cathode without any complicate process.

  19. Chemically durable iron phosphate glasses for vitrifying sodium bearing waste (SBW) using conventional and cold crucible induction melting (CCIM) techniques

    Energy Technology Data Exchange (ETDEWEB)

    Kim, C.W. E-mail: cheol@umr.edu; Ray, C.S.; Zhu, D.; Day, D.E.; Gombert, D.; Aloy, A.; Mogus-Milankovic, A.; Karabulut, M

    2003-11-01

    A simulated sodium bearing waste (SBW) was successfully vitrified in iron phosphate glasses (IPG) at a maximum waste loading of 40 wt% using conventional and cold crucible induction melting (CCIM) techniques. No sulfate segregation or crystalline phases were detectable in the IPG when examined by SEM and XRD. The IPG wasteforms containing 40 wt% SBW satisfy current DOE requirements for aqueous chemical durability as evaluated from their bulk dissolution rate (D{sub R}), product consistency test, and vapor hydration test. The fluid IPG wasteforms can be melted at a relatively low temperature (1000 deg. C) and for short times (<6 h). These properties combined with a significantly higher waste loading, and the feasibility of CCIM melting offer considerable savings in time, energy, and cost for vitrifying the SBW stored at the Idaho National Engineering and Environmental Laboratory in iron phosphate glasses.

  20. Radiative properties and luminescence spectra of Sm{sup 3+} ion in zinc–aluminum–sodium-phosphate (ZANP) glasses

    Energy Technology Data Exchange (ETDEWEB)

    Brahmachary, K.; Rajesh, D.; Ratnakaram, Y.C., E-mail: ratnakaramsvu@gmail.com

    2015-05-15

    The fluorescence properties of different concentrations of Sm{sup 3+} doped zinc–aluminum–sodium-phosphate (ZANP) glasses were studied by the XRD, SEM, FTIR, TG–DTA, optical absorption, photoluminescence and decay cure analysis. X-ray diffraction profiles and SEM images confirmed the amorphous nature of the glass samples. Structural information of these glass matrices was provided by FTIR spectrum. Judd–Ofelt (J–O) theory was applied to the experimental oscillator strengths to evaluate three phenomenological J–O intensity parameters, Ω{sub λ} (λ=2, 4 and 6). Using J–O intensity parameters and emission spectra, various radiative parameters such as radiative transition probabilities (A{sub R}), radiative lifetimes (τ{sub R}), calculated and measured branching ratios (β{sub R} and β{sub m}), effective bandwidths (Δλ{sub eff}) and stimulated emission cross-sections (σ{sub P}) were calculated for observed emission transitions. The intensity of emission transitions with the variation of Sm{sup 3+} ion concentration was studied. The nature of decay curves of {sup 4}G{sub 5/2} level for different Sm{sup 3+} ion concentrations in ZANP glass was analyzed and obtained measured lifetimes (τ{sub exp}). Quantum efficiency of {sup 4}G{sub 5/2} level was calculated based on experimental and measured radiative lifetimes (τ{sub exp} and τ{sub R}). - Highlights: • The amorphous nature of glasses was confirmed due to lack of sharp peaks in the XRD profiles. • Higher covalency and rigidity were obtained in ZANPSm05 and ZANPSm15 glass matrices respectively. • The symmetric nature present in ZANP glass matrix is confirmed from MD transition, {sup 4}G{sub 5/2}→{sup 6}H{sub 7/2} of Sm{sup 3+} ion. • The decrease of intensity of emission transitions beyond 0.5 mol% is attributed to dipole–dipole interactions. • Among all the glass matrices studied, all the spectroscopic parameters are higher in ZANPSm05 glass matrix.

  1. Structural and luminescence studies of Ho{sup 3+}-doped zinc-aluminium-sodium-phosphate (ZANP) glasses

    Energy Technology Data Exchange (ETDEWEB)

    Brahmachary, K.; Rajesh, D.; Ratnakaram, Y. C., E-mail: ratnakaramsvu@gmail.com [Department of Physics, Sri Venkateswara University, Tirupati-517502 (India)

    2015-06-24

    Trivalent holmium doped zinc-aluminium-sodium-phosphate (ZANP) glasses were prepared by conventional melt-quenching technique and characterized for their structural and luminescence properties. The amorphous nature, elemental analysis and thermal stability of the glasses were studied by using X-ray diffraction, energy dispersive spectrum and differential scanning calorimetry analysis, respectively. The absorption and fluorescence spectra have been recorded at room temperature. Based on the absorption spectra, the Judd-Ofelt parameters and radiative parameters such as spontaneous transition probabilities (A{sub R}), branching ratios (β{sub R}), radiative lifetimes (τ{sub R}) were calculated and discussed. From the emission spectra emission peak positions (λ{sub P}), effective bandwidths (Δλ{sub eff}) and stimulated emission cross-sections (σ{sub P}) were calculated for the observed emission transitions,{sup 5}S{sub 2} ({sup 5}F{sub 4}→{sup 5}I{sub 8}) and {sup 5}F{sub 5}→{sup 5}I{sub 8} in all the glass samples. The stimulated emission cross-section is higher for ZANPHo10 glass matrix and so it may be useful for laser excitation.

  2. FY-97 operations of the pilot-scale glass melter to vitrify simulated ICPP high activity sodium-bearing waste

    International Nuclear Information System (INIS)

    Musick, C.A.

    1997-11-01

    A 3.5 liter refractory-lined joule-heated glass melter was built to test the applicability of electric melting to vitrify simulated high activity waste (HAW). The HAW streams result from dissolution and separation of Idaho Chemical Processing Plant (ICPP) calcines and/or radioactive liquid waste. Pilot scale melter operations will establish selection criteria needed to evaluate the application of joule heating to immobilize ICPP high activity waste streams. The melter was fabricated with K-3 refractory walls and Inconel 690 electrodes. It is designed to be continuously operated at 1,150 C with a maximum glass output rate of 10 lbs/hr. The first set of tests were completed using surrogate HAW-sodium bearing waste (SBW). The melter operated for 57 hours and was shut down due to excessive melt temperatures resulting in low glass viscosity (< 30 Poise). Due to the high melt temperature and low viscosity the molten glass breached the melt chamber. The melter has been dismantled and examined to identify required process improvement areas and successes of the first melter run. The melter has been redesigned and is currently being fabricated for the second run, which is scheduled to begin in December 1997

  3. REACTION PRODUCTS AND CORROSION OF MOLYBDENUM ELECTRODE IN GLASS MELT CONTAINING ANTIMONY OXIDES AND SODIUM SULFATE

    Directory of Open Access Journals (Sweden)

    JIŘÍ MATĚJ

    2012-09-01

    Full Text Available The products on the interface of a molybdenum electrode and glass melt were investigated primarily at 1400°C in three model glass melts without ingredients, with 1 % Sb2O3 and with 1 % Sb2O3 and 0.5 % SO3 (wt. %, both under and without load by alternating current. Corrosion of the molybdenum electrode in glass melt without AC load is higher by one order of magnitude if antimony oxides are present. The corrosion continues to increase if sulfate is present in addition to antimony oxides. Isolated antimony droplets largely occur on the electrode-glass melt interface, and numerous droplets are also dissipated in the surrounding glass if only antimony oxides are present in the glass melt. A comparatively continuous layer of antimony occurs on the interface if SO3 is also present, antimony being always in contact with molybdenum sulfide. Almost no antimony droplets are dissipated in the glass melt. The total amount of precipitated antimony also increases. The presence of sulfide on the interface likely facilitates antimony precipitation. The reaction of molybdenum with antimony oxides is inhibited in sites covered by an antimony layer. The composition of sulfide layers formed at 1400°C approximates that of Mo2S3. At 1100°C, the sulfide composition approximates that of MoS4. Corrosion multiplies in the glass melt without additions through the effect of AC current, most molybdenum being separated in the form of metallic particles. Corrosion also increases in the glass melt containing antimony oxides. This is due to increased corrosion in the neighborhood of the separated antimony droplets. This mechanism also results in the loosening of molybdenum particles. The amount of precipitated antimony also increases through the effect of the AC current. AC exerts no appreciable effect on either corrosion, the character of the electrode-glass interface, or antimony precipitation in the glass melt containing SO3.

  4. Cation modulation of hemoglobin interaction with sodium n-dodecyl sulphate (SDS) iv: magnesium modulation at pH 7.20

    OpenAIRE

    Ali Akbar Moosavi-Movahedi; Ferdinand C. Chilaka; Charles O. Nwamba

    2016-01-01

    We investigate the interaction of Mg2+ (0–2.30 mM) and sodium n-dodecyl sulfate (SDS) with hemoglobins (Hbs) A and S at pH 7.20. SDS was used to model both membranes (0.60 mM SDS) and proteases (5.0 mM SDS). Via UV-visible spectroscopy, second derivative and difference second derivative spectroscopy, we interrogated for difference(s) in the interaction of these ligands with the proteins that can account for the HbS resistance to malaria parasite while been prone to sickling. Our results show ...

  5. Nanostructured sodium lithium niobate and lithium niobium tantalate solid solutions obtained by controlled crystallization of glass

    International Nuclear Information System (INIS)

    Radonjic, L.; Todorovic, M.; Miladinovic, J.

    2005-01-01

    Transparent, nanostructured glass ceramics based on ferroelectric solid solutions of the type Na 1-x Li x NbO 3 (in very narrow composition regions for x = 0.12 and 0.93) and LiNb 1-y Ta y O 3 (y = 0.5 unlimited solid solubility), can be obtained by controlled crystallization of glass. The parent glass samples were prepared by conventional melt-quenching technique. Heat-treatment of the parent glasses was performed at the various temperatures, for the same time. The glass structure evolution during the controlled crystallization was examined by FT-IR spectroscopy analysis. Crystalline phases were identified by X-ray diffraction analysis and SEM was used for microstructure characterization. Densities of the crystallized glasses were measured by Archimedean principle. The capacitance and dielectric loss tangent were measured at a frequency of 1 kHz, at the room temperature. It was found that in the all investigated systems crystallize solid solutions Na 1-x Li x NbO 3 and LiNb 1-y Ta y O 3 in the glassy matrix, have crystal size on nanoscale (less than 100 nm), which is one of requirements to get a transparent glass ceramic that could be a good ferroelectric material regarding to the measured properties

  6. Energy transfer upconversion in Er3+-Tm3+ codoped sodium silicate glass

    Science.gov (United States)

    Kumar, Vinod; Pandey, Anurag; Ntwaeaborwa, O. M.; Swart, H. C.

    2018-04-01

    Er3+/Tm3+ doped and codoped Na2O-SiO2-ZnO (NSZO) glasses were prepared by the conventional melt-quenching method. The amorphous nature of the prepared glasses was confirmed by the X-ray diffraction analysis. The optical absorption spectrum displayed several peaks, which correspond to Er3+ and Tm3+ dopant ions embedded into the NSZO glass. Both dopants experienced upconversion emission under 980 nm excitation. Efficient energy transfer from Er3+ to Tm3+ was observed in the co-doped samples to enhance the near infrared emission of the Tm3+ ions.

  7. Sodium aluminum-iron phosphate glass-ceramics for immobilization of lanthanide oxide wastes from pyrochemical reprocessing of spent nuclear fuel

    Science.gov (United States)

    Stefanovsky, S. V.; Stefanovsky, O. I.; Kadyko, M. I.; Nikonov, B. S.

    2018-03-01

    Sodium aluminum (iron) phosphate glass ceramics containing of up to 20 wt.% rare earth (RE) oxides simulating pyroprocessing waste were produced by melting at 1250 °C followed by either quenching or slow cooling to room temperature. The iron-free glass-ceramics were composed of major glass and minor phosphotridymite and monazite. The iron-bearing glass-ceramics were composed of major glass and minor monazite and Na-Al-Fe orthophosphate at low waste loadings (5-10 wt.%) and major orthophosphate and minor monazite as well as interstitial glass at high waste loadings (15-20 wt.%). Slowly cooled samples contained higher amount of crystalline phases than quenched ones. Monazite is major phase for REs. Leach rates from the materials of major elements (Na, Al, Fe, P) are 10-5-10-7 g cm-2 d-1, RE elements - lower than 10-5 g cm-2 d-1.

  8. Investigation of structure and magnetic properties of cobalt-nickel and manganese ferrites nanoparticles synthesized in direct micelles of sodium dodecyl sulphate system

    International Nuclear Information System (INIS)

    Fedosyuk, V.M.; Mirgorod, Yu.A.

    2016-01-01

    Results of investigation of the crystal structure and magnetic properties of the nanoparticles of transition metals ferrites (cobalt, nickel, manganese) synthesized by unified methods using direct sodium dodecyl sulfate micelles are presented. Crystal structure of the samples was investigated by X-ray diffraction on DRON-3M (in the CuKa-radiation). Particle size was investigated by transmission electron microscopy on microscope JEOL JEM-1011 (accelerating voltage 100 kV). All powders contain nanoparticles of the same size in the range 2-6 nm. Magnetic properties of the samples were estimated from temperature and field dependences of the magnetization. All samples exhibit properties of superparamagnets with different blocking temperatures below 45 K. (authors).

  9. Glasses

    DEFF Research Database (Denmark)

    Dyre, Jeppe

    2004-01-01

    The temperature dependence of the viscosity of most glassforming liquids is known to depart significantly from the classical Arrhenius behaviour of simple fluids. The discovery of an unexpected correlation between the extent of this departure and the Poisson ratio of the resulting glass could lead...... to new understanding of glass ageing and viscous liquid dynamics....

  10. Selection of a glass-ceramic formulation to immobilize fluorinel- sodium calcine

    International Nuclear Information System (INIS)

    Staples, B.A.; Wood, H.C.

    1994-12-01

    One option for immobilizing calcined high level wastes produced by nuclear fuel reprocessing activities at the Idaho Chemical Processing Plant (ICPP) is conversion to a glass-ceramic form through hot isostatic pressing. Calcines exist in several different chemical compositions, and thus candidate formulations have been developed for converting each to glass-ceramic forms which are potentially resistant to aqueous corrosion and stable enough to qualify for repository storage. Fluorinel/Na, a chemically complex calcine type, is one of the types being stored at ICPP, and development efforts have identified three formulations with potential for immobilizing it. These are a glass forming additive that uses aluminum metal to enhance reactivity, a second glass forming additive that uses titanium metal to enhance reactivity and a third that uses not only a combination of silicon and titanium metals but enough phosphorous pentoxide to form a calcium phosphate host phase in the glass-ceramic product. Glass-ceramics of each formulation performed well in restricted characterization tests. However, none of the three was subjected to rigorous testing that would provide information on whether each was processable, that is able to retain favorable characteristics over a practical range of processing conditions

  11. Compatibility of butorphanol with granisetron in 0.9% sodium chloride injection packaged in glass bottles or polyolefin bags.

    Science.gov (United States)

    Chen, Fu-Chao; Xiong, Hui; Liu, Hui-Min; Fang, Bao-Xia; Li, Peng

    2015-08-15

    The stability of admixtures containing butorphanol and granisetron in polyolefin bags and glass bottles stored at 4 and 25 °C was studied. Commercial solutions of butorphanol tartrate and granisetron hydrochloride were combined and further diluted with 0.9% sodium chloride injection to final concentrations of butorphanol tartrate 0.08 mg/mL and granisetron 0.03 or 0.06 mg/mL; the resulting mixtures were packaged in polyolefin bags and glass bottles. The admixtures were assessed for periods of up to 48 hours after storage at 25 °C without protection from room light and up to 14 days at 4 °C with protection from room light. The chemical stability of the admixtures was evaluated by a validated high-performance liquid chromatography (HPLC) method and by measurement of pH values. Solution appearance and color were assessed by observing the samples against room light and dark backgrounds. HPLC analysis demonstrated that the percentages of the initial concentrations of butorphanol and granisetron in the various solutions remained above 97% during the testing period. No changes in color or turbidity were observed in any of the prepared solutions. Throughout this period, pH values remained stable. Admixtures of butorphanol tartrate 0.08 mg/mL and granisetron 0.03 or 0.06 mg/mL in 0.9% sodium chloride injection in polyolefin bags or glass bottles remained stable for 48 hours when stored at 25 °C exposed to room light and for 14 days when stored at 4 °C protected from room light. Copyright © 2015 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  12. Optical study of gamma irradiated sodium metaphosphate glasses containing divalent metal oxide MO (ZnO or CdO

    Directory of Open Access Journals (Sweden)

    E. Nabhan

    Full Text Available Sodium metaphosphate glasses containing divalent metal oxide, ZnO or CdO with composition 50 P2O5 – (50 − x Na2O – x MO (ZnO, or CdO where x = 0, 10, 20 (mol% were prepared by conventional melt method. UV/visible spectroscopy and FTIR spectroscopy are measured before and after exposing to successive gamma irradiation doses (5–80 kGy. The optical absorption spectra results of the samples before irradiation reveal a strong UV absorption band at (∼230 nm which is related to unavoided iron impurities. The effects of gamma irradiation on the optical spectral properties of the various glasses have been compared. From the optical absorption spectral data, the optical band gap is evaluated. The main structural groups and the influence of both divalent metal oxide and gamma irradiation effect on the structural vibrational groups are realized through IR spectroscopy. The FTIR spectra of γ-irradiated samples are characterized by the stability of the number and position for the main characteristic band of phosphate groups. To better understood the structural changes during γ-irradiation, a deconvolution of FTIR spectra in the range 650–1450 cm−1 is made. The FTIR deconvolution results found evidence that, the changes occurring after gamma irradiation have been related to irradiation induced structural defects and compositional changes. Keywords: Sodium metaphosphate glass, UV–visible spectra, IR spectra, Deconvolution, Optical band gap, Gamma ray

  13. Hydrothermal reaction of albite and a sodium aluminosilicate glass: A solid-state NMR study

    Science.gov (United States)

    Yang, Wang-hong Alex; Kirkpatrick, R. James

    1989-04-01

    We present here a solid-state NMR study of the structure and chemical composition of the products and mechanisms of the reaction of crystalline low albite and a glass of nearly albite composition with aqueous solutions of pH from 1 to 11 at 250°C. For the crystalline albite, there are no detectable bulk or surface structural changes due to aqueous attack, consistent with the idea that both cation exchange and disruption of the aluminosilicate framework occur only near the mineral/solution interface and that the hydrated surface layer, if it exists, is not more than about 30 Å thick. This reaction occurs by solution/reprecipitation, and its rate decreases with increasing solution pH, supporting the idea that the dissolution of feldspar is initiated by cation-exchange. For the glass, the reaction proceeds by cation exchange of protons for Na +, incorporation of molecular water into the bulk glass, and a small amount of depolymerization of the aluminosilicate framework in the interior of the glass. Cation exchange becomes less important with increasing solution pH. The incorporation of molecular water and cation-exchange cause structural changes in the glass via solidstate adjustment without dissolution/reprecipitation. The large cations in the hydrated glass (Na and K) probably have a shell of water molecules around them, with a maximum average coordination number of six. The secondary phases formed from both albite and the glass are often amorphous and can be well characterized by NMR. The compositional and structural variations of the amorphous phases are important factors in these reactions and cannot be ignored in theoretical models of aluminosilicate dissolution. As expected, the aluminum coordination in the secondary phases changes from six-fold to four-fold as the solution pH increases.

  14. Tumor necrosis factor-α and Muc2 mucin play major roles in disease onset and progression in dextran sodium sulphate-induced colitis.

    Directory of Open Access Journals (Sweden)

    Poonam Dharmani

    Full Text Available The sequential events and the inflammatory mediators that characterize disease onset and progression of ulcerative colitis (UC are not well known. In this study, we evaluated the early pathologic events in the pathogenesis of colonic ulcers in rats treated with dextran sodium sulfate (DSS. Following a lag phase, day 5 of DSS treatment was found clinically most critical as disease activity index (DAI exhibited an exponential rise with severe weight loss and rectal bleeding. Surprisingly, on days 1-2, colonic TNF-α expression (70-80-fold and tissue protein (50-fold were increased, whereas IL-1β only increased on days 7-9 (60-90-fold. Days 3-6 of DSS treatment were characterized by a prominent down regulation in the expression of regulatory cytokines (40-fold for IL-10 and TGFβ and mucin genes (15-18 fold for Muc2 and Muc3 concomitant with depletion of goblet cell and adherent mucin. Remarkably, treatment with TNF-α neutralizing antibody markedly altered DSS injury with reduced DAI, restoration of the adherent and goblet cell mucin and IL-1β and mucin gene expression. We conclude that early onset colitis is dependent on TNF-α that preceded depletion of adherent and goblet cell mucin prior to epithelial cell damage and these biomarkers can be used as therapeutic targets for UC.

  15. Detection of metalloproteins in human liver cytosol by synchrotron radiation X-ray fluorescence after sodium dodecyl sulphate polyacrylamide gel electrophoresis

    International Nuclear Information System (INIS)

    Gao Yuxi; Chen Chunying; Zhang Peiqun; Chai Zhifang; He Wei; Huang Yuying

    2003-01-01

    An improved method of analysis of metals in protein bands with synchrotron radiation X-ray fluorescence (SRXRF) after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) separation is introduced and applied to human liver cytosol. Through a step of drying the gel before SRXRF determination, the continuous background resulting mainly from the Compton-scattering of X-rays by the gel matrix was substantially reduced, and the detection of biological trace elements, such as Cu, Fe, and Zn in protein bands was thereby made possible. With the new procedure, six Zn-containing proteins with molecular weights (MWs) of 17.5, 20.5, 27, 35, 55, and 63 kDa, respectively were found in human liver cytosol, among which the 63 kDa Zn-containing band was shown to be the dominant form of zinc. In addition, at least four Fe containing proteins with MWs of 20, 23, 43, and 83.5 kDa, respectively, were present in the samples. The metal contents in some metalloproteins, such as the 63 kDa Zn-containing protein, the 23 and 83.5 kDa Fe-containing proteins, and a 22 kDa Cu-containing protein were more closely related to the metal level in the sample. It is demonstrated that the procedure could be widely used to further investigate metal-binding proteins in biological samples

  16. Physical and optical property studies on Bi3+ ion containing vanadium sodium borate glasses

    Science.gov (United States)

    Venkatesh, G.; Meera, B. N.; Eraiah, B.

    2018-04-01

    xBi2O3-(15-x)V2O5-45B2O3-40Na2O glasses have been prepared using melt quenching technique. Amorphous nature of the glasses is verified using powder XRD. Densities and molar volume have been determined as a function of bismuth content and interestingly both increases as a function of bismuth content. Further oxygen packing density (OPD) is found to decrease with bismuth content. The increase in the molar volume as a function of bismuth content may be due to structural changes in the glass network. The optical properties performed from the optical absorption spectra were recorded in the wavelength range 200-1100 nm using UV-Visible spectrophotometer. The theoretical optical basicity of the oxides have also been estimated. The calculated energy band gap values increases with increase in Bi2O3 content.

  17. Comparison of the effects of sodium hyaluronate-chondroitin sulphate and corticosteroid in the treatment of lateral epicondylitis: a prospective randomized trial.

    Science.gov (United States)

    Tosun, Haci Bayram; Gumustas, Seyitali; Agir, Ismail; Uludag, Abuzer; Serbest, Sancar; Pepele, Demet; Ertem, Kadir

    2015-09-01

    Hyaluronic acid and glycosaminoglycans have shown positive effects in improving lateral epicondylitis and other tendinosis conditions. Therefore, we designed a prospective, randomized study to compare the effects of a combined sodium hyaluronate and chondroitin sulfate (HA + CS) injection versus a triamcinolone injection in the treatment of lateral epicondylitis. In total, 57 consecutive patients with clinically diagnosed lateral epicondylitis were divided randomly into two groups. In the HA + CS group, 25 patients received a single injection of a solution containing an HA + CS combination and prilocaine HCl, while the 32 patients in the triamcinolone group received a single injection of a solution of triamcinolone and prilocaine HCl. We evaluated the pain and function outcome measures using the Patient-Rated Tennis Elbow Evaluation (PRTEE) questionnaire at the beginning of the study, and 3 and 6 months after the injection. Additionally, the Minimum Clinically Important Difference values and percentage changes in the PRTEE subscale scores between the assessments were calculated. No serious adverse events were reported throughout the study. The mean pain and function scores for the HA + CS and triamcinolone groups had significantly improved at 3 months, but the mean function scores in the HA + CS group were statistically significantly better when compared to the triamcinolone group. At 6 months, both groups had significantly improved mean pain and function scores, compared to the baseline scores; however, the mean pain and function scores in the 6-month HA + CS treatment group were better than in the 6-month triamcinolone group. The relative change for the mean total score in the HA + CS group was much better when compared with the triamcinolone group, and the HA + CS treatment group showed clinically significant improvement when compared with triamcinolone group at 3 and 6 months. This study supports the idea that for a single injection treatment of patients with

  18. Cation modulation of hemoglobin interaction with sodium n-dodecyl sulphate (SDS iv: magnesium modulation at pH 7.20

    Directory of Open Access Journals (Sweden)

    Ali Akbar Moosavi-Movahedi

    2016-03-01

    Full Text Available We investigate the interaction of Mg2+ (0–2.30 mM and sodium n-dodecyl sulfate (SDS with hemoglobins (Hbs A and S at pH 7.20. SDS was used to model both membranes (0.60 mM SDS and proteases (5.0 mM SDS. Via UV-visible spectroscopy, second derivative and difference second derivative spectroscopy, we interrogated for difference(s in the interaction of these ligands with the proteins that can account for the HbS resistance to malaria parasite while been prone to sickling. Our results show that Mg2+ interaction with the proteins lowered the HbS oxygen affinity in comparison with the HbA. Additionally, [SDS]-protein interactions resulted in oxoferryl heme species formation that was prominent for the HbA and highly diminished for the HbS. [Mg2+] introduction to the [SDS]-protein mixture, however decreased the concentration of denatured protein species. The [Mg2+]-[SDS]-protein interactions suggest that while ionic or coulomb interactions for the HbA, in the presence of the surfactants, are [Mg2+] dependent, those of the HbS are not. Furthermore, hydrophobicity is a crucial force for the HbS interaction at neutral pH and is little-masked by ionic, electrostatic or coulombic interactions. In conclusion, at physiological pH, the Mg-SDS interaction decreased the HbS denaturation in comparison to the HbA.

  19. sodium

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les initiatives de réduction de la consommation de sel qui visent l'ensemble de la population et qui ciblent la teneur en sodium des aliments et sensibilisent les consommateurs sont susceptibles de réduire la consommation de sel dans toutes les couches de la population et d'améliorer la santé cardiovasculaire. Ce projet a ...

  20. Gold nanoparticles assisted surface enhanced Raman scattering and luminescence of Er{sup 3+} doped zinc–sodium tellurite glass

    Energy Technology Data Exchange (ETDEWEB)

    Ghoshal, S.K.; Awang, Asmahani, E-mail: asmahani_awang@yahoo.com; Sahar, M.R.; Arifin, R.

    2015-03-15

    Significant enhancements in Er{sup 3+} luminescence and Raman intensity mediated via surface plasmon resonance (SPR) of gold (Au) nanoparticles (NPs) embedded zinc–sodium tellurite glass are reported. The observed modifications in the physical and spectroscopic properties are ascribed to the alterations in the glass network. XRD pattern confirms the amorphous nature of prepared glass sample. UV–vis-NIR spectra reveal seven absorption bands. Surface plasmon band is evidenced around 626–630 nm. TEM images manifest the growth of non-spherical Au NPs with average diameter between ∼7.2 nm and 8.6 nm. The visible up-conversion (UC) emission for all samples under 779 nm excitation exhibits three bands centered at 503 nm (green), 546 (green) and 637 nm (red) ascribed to {sup 2}H{sub 11/2}→{sup 4}I{sub 15/2}, {sup 4}S{sub 3/2}→{sup 4}I{sub 15/2} and {sup 4}F{sub 9/2}→{sup 4}I{sub 15/2} transitions. Glass sample with 0.4 mol% Au displaying the highest luminescence intensity with enhancement factor of 3.85 and 3.56 for green bands, and 7.61 for the red band is ascribed to the NPs local field enhancement and energy transfer between rare earth (RE) ions and NPs. FTIR spectra show the vibration of ZnO{sub 4} bonds, Te-O bond in TeO{sub 3} (tp) and TeO{sub 4} (tbp) units and the hydroxyl groups. Raman spectra demonstrate the presence of Er-O and Zn-O bond, anti-symmetric vibrations of Te-O-Te bonds and stretching modes of non-bonded oxygen exists in TeO{sub 3} and TeO{sub 3+1} unit. The amplifications in Raman signals by a factor of 1.62, 1.58, 1.64, 1.68 and 1.69 corresponding to the peak centered at 262 cm{sup −1}, 382 cm{sup −1}, 521 cm{sup −1}, 670 cm{sup −1} and 725 cm{sup −1} are attributed to the contribution of a surface plasmon generating a strong, localized and secondary field. We assert that our glass compositions offer favorable potential to develop solid state lasers and other versatile nanophotonic devices. - Highlights: • Gold

  1. Reaction products and corrosion of molybdenum electrode in glass melt containing antimony oxides and sodium sulfate

    Czech Academy of Sciences Publication Activity Database

    Matěj, J.; Langrová, Anna

    2012-01-01

    Roč. 56, č. 3 (2012), s. 280-285 ISSN 0862-5468 Institutional support: RVO:67985831 Keywords : antimony oxides * corrosion * glass melt * Molybdenum electrode * sulfate Subject RIV: DD - Geochemistry Impact factor: 0.418, year: 2012 http://www.ceramics-silikaty.cz/2012/pdf/2012_03_280.pdf

  2. Luminescence properties of erbium doped sodium barium borate glass with silver nanoparticles

    Science.gov (United States)

    Rajeshree Patwari, D.; Eraiah, B.

    2018-02-01

    Alteration in the absorption features of rare earth (RE) doped glasses with silver nanoparticles is ever-challenging in photonics. Erbium (Er3+) doped glasses with composition (60-x-y)B2O3-30Na2CO3-10BaO-xEr2O3-yAgCl where (x=0.5, 1.0 and y=1.0 mol %) are synthesized using melt-quenching method. The density is determined by Archimedes principle and molar volumes are calculated. Glass samples were characterized by XRD and UV-Visible spectroscopy. UV-Visible spectra shows eleven prominent absorption peaks centred around 366, 378, 408, 442, 452, 489, 521, 547, 652, 800 and 977 nm equivalent to the rare earth (Er3+) ion transitions. The sample without rare earth shows no peaks which specifies that rare earth ion plays a spirited role in the glass matrix. The glass samples with silver and without rare earth ion shows plasmon peak on heat treatment. The energy band gap values calculated for direct and indirect transitions are in the range of 3.126-3.440eV and 2.58-3.177eV respectively. The refractive indices and Urbach energies are also determined. Photoluminescence spectra are recorded and studied for excitation of the most intense peaks of wavelengths 378 and 521nm. The luminescence of erbium ion is enhanced by the presence of silver when the concentration of rare earth ion is less than that of silver.

  3. Anti-inflammatory effects of the selective phosphodiesterase 3 inhibitor, cilostazol, and antioxidants, enzymatically-modified isoquercitrin and α-lipoic acid, reduce dextran sulphate sodium-induced colorectal mucosal injury in mice.

    Science.gov (United States)

    Kangawa, Yumi; Yoshida, Toshinori; Abe, Hajime; Seto, Yoshiki; Miyashita, Taishi; Nakamura, Michi; Kihara, Tohru; Hayashi, Shim-Mo; Shibutani, Makoto

    2017-04-04

    Developing effective treatments and preventing inflammatory bowel disease (IBD) are urgent challenges in improving patients' health. It has been suggested that platelet activation and reactive oxidative species generation are involved in the pathogenesis of IBD. We examined the inhibitory effects of a selective phosphodiesterase-3 inhibitor, cilostazol (CZ), and two antioxidants, enzymatically modified isoquercitrin (EMIQ) and α-lipoic acid (ALA), against dextran sulphate sodium (DSS)-induced colitis. BALB/c mice were treated with 0.3% CZ, 1.5% EMIQ, and 0.2% ALA in their feed. Colitis was induced by administering 5% DSS in drinking water for 8days. The inhibitory effects of these substances were evaluated by measuring relevant clinical symptoms (faecal blood, diarrhoea, and body weight loss), colon length, plasma cytokine and chemokine levels, whole genome gene expression, and histopathology. Diarrhoea was suppressed by each treatment, while CZ prevented shortening of the colon length. All treatment groups exhibited decreased plasma levels of interleukin (IL)-6 and tumour necrosis factor (TNF)-α compared with the DSS group. Microarray analysis showed that cell adhesion, cytoskeleton regulation, cell proliferation, and apoptosis, which might be related to inflammatory cell infiltration and mucosal healing, were affected in all the groups. DSS-induced mucosal injuries such as mucosal loss, submucosal oedema, and inflammatory cell infiltration in the distal colon were prevented by CZ or antioxidant treatment. These results suggest that anti-inflammatory effects of these agents reduced DSS-induced mucosal injuries in mice and, therefore, may provide therapeutic benefits in IBD. Copyright © 2016 Elsevier GmbH. All rights reserved.

  4. Water speciation in sodium silicate glasses (quenched melts): A comprehensive NMR study

    Science.gov (United States)

    Xue, X.; Kanzaki, M.; Eguchi, J.

    2012-12-01

    Dissolution mechanism of water is an important factor governing how the dissolved water affects the physical and thermodynamic properties of silicate melts and glasses. Our previous studies have demonstrated that 1H MAS NMR in combination with 29Si-1H and 27Al-1H double-resonance NMR experiments is an effective approach for unambiguously differentiating and quantifying different water species in quenched silicate melts (glasses). Several contrasting dissolution mechanisms have been revealed depending on the melt composition: for relatively polymerized melts, the formation of SiOH/AlOH species (plus molecular H2O) and depolymerization of the network structure dominate; whereas for depolymerized Ca-Mg silicate melts, free OH (e.g. MgOH) become increasingly important (cf. [1]). The proportion of free OH species has been shown to decrease with both increasing melt polymerization (silica content) and decreasing field strength of the network modifying cations (from Mg to Ca). Our previous 1H and 29Si MAS NMR results for hydrous Na silicate glasses of limited compositions (Na2Si4O9 and Na2Si2O5) were consistent with negligible free OH (NaOH) species and depolymerizing effect of water dissolution [2]. On the other hand, there were also other studies that proposed the presence of significant NaOH species in hydrous glasses near the Na2Si2O5 composition. The purpose of this study is apply the approach of combined 1H MAS NMR and double-resonance (29Si-1H and 23Na-1H) NMR to gain unambiguous evidence for the OH speciation in Na silicate glasses (melts) as a function of composition. Hydrous Na silicate glasses containing mostly ≤ 1 wt% H2O for a range of Na/Si ratios from 0.33 to 1.33 have been synthesized by rapidly quenching melts either at 0.2 GPa using an internally heated gas pressure vessel or at 1 GPa using a piston cylinder high-pressure apparatus. NMR spectra have been acquired using a 9.4 T Varian Unity-Inova spectrometer. The 29Si and 1H chemical shifts are

  5. Action of arginine for protection of ulcerative colitis by dextran sodium sulphate (DSS); Acao da arginina na protecao da colite ulcerativa induzida por sulfato de sodio dextrano

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Maria Emilia Rabelo

    2016-10-01

    Recent studies have demonstrated the benefits of immunomodulators, such as arginine, in the regulation of inflammatory responses and trophism of the intestinal mucosa. The aim of this study was to evaluate the possible mechanisms action of arginine (pretreatment or treatment) in experimental model of ulcerative colitis induced by dextran sodium sulfate (DSS). C57BL/6 mice were randomized into 5 groups: Control group (C): standard diet and water; Arginine group (ARG): diet supplementation with arginine and water; Colitis group (COL): standard diet and DSS solution; Pretreated group (PT): diet supplementation with arginine before and during colitis induction; Treated group (T): diet supplementation with arginine during colitis induction. Colitis was induced by administration of 1.5% DSS for 5 days. After this, all the mice were euthanized and blood, organs and intestinal fluid were collected for carrying out analyzes. Parameters such as intestinal permeability (IP), bacterial translocation (BT), histological analysis (histological score, morphometric analysis, collagen and mucins stain), nitrate and nitrite, cytokines and chemokines, secretory immunoglobulin A (sIgA), inflammatory infiltrate and oxidative stress were performed. The ARG group did not show difference compared to group C in the investigated parameters (C vs ARG: p> 0.05). The COL group showed increased IP (C vs COL: p < 0.05) and BT (C vs COL: p <0.05). In the histological analysis, the COL group showed severe inflammation and reduction the crypts length. In addition, in the group COL observed increase infiltration of eosinophils, neutrophils and macrophages in the colon, increase cytokine IL-17 and chemokine KC in serum and oxidative stress in the colon (COL vs C: p <0.05). In the arginine-supplemented groups (PT and T) was observed decrease IP and BT to blood, liver and lung (PT and T vs Col: p <0.05). Histological analysis showed that the arginine (PT and T) preserved the intestinal mucosa and crypts

  6. Photoluminescence study of Er-doped zinc-sodium-antimonite glasses

    Czech Academy of Sciences Publication Activity Database

    Zavadil, Jiří; Ivanova, Z. G.; Kostka, Petr; Hamzaoui, M.; Soltani, M.

    2014-01-01

    Roč. 611, 25 October (2014), s. 111-116 ISSN 0925-8388 R&D Projects: GA ČR GAP106/12/2384; GA MŠk(CZ) 7AMB14SK009 Institutional support: RVO:67985882 ; RVO:67985891 Keywords : Erbium * Photoluminescence * Antimonite glasses Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering; BM - Solid Matter Physics ; Magnetism (USMH-B) Impact factor: 2.999, year: 2014

  7. Optical and luminescence properties of Dy3+ doped sodium silicate glass

    Science.gov (United States)

    Srisittipokakun, N.; Kaewkhao, J.

    2017-07-01

    The aim of the present work is to study the optical and luminescence properties of Dy2O3 doped Na2O-BaO-Bi2O3-SiO2 glasses. The Dy3+ ion is chosen as dopant because it emits three visible bands, blue (470-485 nm; 4F9/2→6H15/2), yellow (570-580 nm; 4F9/2→6H13/2) and red (640-655 nm; 4F9/2→6H11/2) luminescence and finds its applications in the fields of laser, white LEDs, telecommunication technology and display devices. NaBaBiSiDy glasses with the compositions of (30-x)SiO2: 10Bi2O3: 30Na2O: 30BaO: xDy2O3 where x=0.0, 0.1, 0.5, 1.0, 1.5 and 2.0 mol% were prepared by melt-quenching technique and characterized by using density, optical absorption photoluminescence (PL) and decay rate measurements as function of different concentrations. The density (ρ), molar volume (VM) and refractive index obtained were found to increase with increase in the concentration of Dy2O3 in the glass matrix. The chromaticity coordinates were calculated from emission spectra and analyzed with CIE color diagram and appear in the white light region under ultraviolet excitation.

  8. 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)

  9. Structural properties of alkaline sodium lead fluoride borate glasses incorporated with Praseodymium ion

    Science.gov (United States)

    Lenkennavar, Susheela K.; Madhu, A.; Eraiah, B.; Kokila, M. K.

    2018-05-01

    The effect of different alkaline and Pr ions on the density and structure of Na2O-PbO-MO-B2O3 (M represents Ba/Ca/Sr) has been investigated using X-ray diffraction (XRD), infrared spectrophotometer (FTIR). The amorphous phase has been identified based on X-ray diffraction analysis. The Praseodymium oxide plays the role as a glass-modifier and influences on BO3↔BO4 conversion. The same effect is also observed in density and molar volume variation due to non bridging oxygen's (NBO) created when BO3 units are converted.

  10. Bacterial Reduction Of Barium Sulphate By Sulphate-Reducing Bacteria

    Directory of Open Access Journals (Sweden)

    Luptáková Alena

    2015-12-01

    Full Text Available Acid mine drainage (AMD is a worldwide problem leading to contamination of water sources. AMD are characterized by low pH and high content of heavy metals and sulphates. The barium salts application presents one of the methods for the sulphates removing from AMD. Barium chloride, barium hydroxide and barium sulphide are used for the sulphates precipitation in the form of barium sulphate. Because of high investment costs of barium salts, barium sulphide is recycled from barium sulphate precipitates. It can be recycled by thermic or bacterial reduction of barium sulphate. The aim of our study was to verify experimentally the possibility of the bacterial transformation of BaSO4 to BaS by sulphate-reducing bacteria. Applied BaSO4 came from experiments of sulphates removal from Smolnik AMD using BaCl2.

  11. Investigation of the electrical conductivity of γ-irradiated sodium silicate glasses containing multivalence Cu ions

    International Nuclear Information System (INIS)

    Tawansi, A.; Basha, A.F.; El-Konsol, S.

    1981-07-01

    The present investigation deals with a study of the γ-radiation effects on the d.c. electrical resistivity (rho) of SiO 2 -Na 2 O-CaO glasses containing Cu 0 , Cu + , Cu 2+ and mixture of Cu + and Cu 2+ ions over the temperature (T) range from 300 to 630 0 K. The applicability of the polaron hopping conduction mechanism has been established from the reciprocal temperature dependence of 1n rho/T for the samples under investigation. The electrical resistivity is found to decrease by increasing the TM valancy which enhances the hoping process. The post-irradiation effect due to ionizing gamma-radiation is investigated within the frame work of the electron (and hole) trapping theory, and an average value of 0.45 is obtained for the parameter Δ, characterizing traps with an exponentially decreasing numbers below the conduction band. (author)

  12. Role of additives; sodium dodecyl sulphate and manganese chloride on morphology of Zn{sub 1−x}Mn{sub x}O nanoparticles and their photoluminescence properties

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, Gajanan, E-mail: pandeygajanan@rediffmail.com [Department of Applied Chemistry, Babasaheb Bhimrao Ambedkar University, Lucknow 226025, U.P. (India); Dixit, Supriya; Shrivastava, A.K. [School of Studies in Physics, Jiwaji University, Gwalior 474011, M.P. (India)

    2014-10-15

    In the present study Zn{sub 1−x}Mn{sub x}O (x = 0, 0.05 and 0.1) nanoparticles (NPs) have been synthesised in aqueous solution phase at mild reaction temperature 100 °C in moderate alkaline medium (pH = 9.5), and the role of external additives; like sodium dodecyl sulphate and manganese chloride on the morphology and size of the products has been explored on the basis of transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectral analyses data. ZnO hexagonal nano-plates, core–shell like spherical/ellipsoidal Zn{sub 0.95}Mn{sub 0.05}O structures and thin sheets, thorn/needle mixed shaped Zn{sub 0.9}Mn{sub 0.1}O structures have been observed in TEM and SEM images. Zn(OH){sub 2} formed in moderate alkaline medium, converted to Zn(II) hydroxo complex ions on dissolution, which further recrystallizes to produce wurtzite ZnO at 100 °C. From XRD and EDX analysis, successful doping of Mn{sup 2+} ions at the Zn{sup 2+} sites in ZnO host has been proved. In the photoluminescence spectra, the observed blue shifts in NBE peaks and decrease of emissions intensity on Mn doping have thoroughly been discussed in the present investigation. - Highlights: • Zn{sub 1−x}Mn{sub x}O NPs have been prepared in aqueous solution at mild temperature 100 °C. • Shifts in XRD lines and NBE peaks in PL spectra proved doping of Mn{sup 2+} in the ZnO. • ZnO is formed via dissolution–recrystallization of ε-Zn(OH){sub 2}–ZnO. • Additives SDS and MnCl{sub 2}·4H{sub 2}O play important role on morphology of Zn{sub 1−x}Mn{sub x}O NPs. • Mn contents increased extrinsic defects, which decreased intensity of PL spectra.

  13. Thermometric titration of sulphate.

    Science.gov (United States)

    Williams, M B; Janata, J

    1970-06-01

    Direct thermometric titration of sulphate with a solution of barium perchlorate is proposed. The stoichiometry of the titration is shown to be critically dependent on the concentration of ethanol in the titration medium. The titration is rapid and suffers from only a few interferences.

  14. Possibilities of Sulphate Elimination from Mine Water

    Directory of Open Access Journals (Sweden)

    Heviánková Silvie

    2004-12-01

    Full Text Available The issue of „acid water“ (or AMD is well known in the world for some centuries. In the Eastern Slovakia, the most acid surface water occurs in the area of old mine Smolník, which is closed and submerged for 15 years. The submitted contribution deals with the sulphate-elimination from this locality. Recently, several methods of sulphate-elimination from the mine water are applied. The best-known methods are biological, physical-chemical and chemical precipitation. The method described in this contribution consists of chemical precipitation by sodium aluminate and calcium hydrate. Under application of this method very interesting results were obtained. The amount of SO42- anions decreased to almost zero-value, using optimal doses of the chemical reagents.

  15. New reddish-orange and greenish-yellow light emitting phosphors: Eu3+ and Tb3+/Eu3+ in sodium germanate glass

    International Nuclear Information System (INIS)

    Álvarez, E.; Zayas, Ma. E.; Alvarado-Rivera, J.; Félix-Domínguez, F.; Duarte-Zamorano, R.P.; Caldiño, U.

    2014-01-01

    A spectroscopic analysis of sodium germanate glasses activated with Eu 3+ , Tb 3+ and Eu 3+ /Tb 3+ is performed from their photoluminescence spectra and decay times. In the Eu 3+ -singly doped glass reddish-orange light emission, with x=0.64 and y=0.35 CIE1931 chromaticity coordinates, is obtained upon Eu 3+ excitation at 393 nm. Such chromaticity coordinates are close to those (0.67, 0.33) proposed by the National Television Standard Committee for the red phosphor. When the sodium germanate glass is co-doped with Tb 3+ and Eu 3+ greenish-yellow light emission, with (0.41, 0.46) CIE1931 chromaticity coordinates, is obtained upon Tb 3+ excitation at 344 nm. Such greenish-yellow luminescence is due mainly to the terbium 5 D 4 → 7 F 6,5 and europium 5 D 0 → 7 F 1,2 emissions, Eu 3+ being sensitized by Tb 3+ through a non-radiative energy transfer. The non-radiative nature of this energy transfer is inferred from the increase in the decay rate of the Tb 3+ emission when the glass is co-doped with Eu 3+ . From an analysis of the Tb 3+ emission decay time curves it is inferred that such energy transfer might take place between Tb 3+ and Eu 3+ clusters through a short-range interaction mechanism. - Highlights: • Sodium germanate glasses are optically activated with Eu 3+ (GNE) and Tb 3+ /Eu 3+ (GNTE). • Reddish-orange light (0.64, 0.35) is generated by GNE pumped with 393 nm light. • Greenish-yellow light (0.41, 0.46) is generated by GNTE pumped with 344 nm light. • Non-radiative energy transfer Tb 3+ →Eu 3+ takes place in GNTE

  16. UV-visible, Raman and E.S.R. studies of gamma-irradiated NiO-doped sodium metaphosphate glasses.

    Science.gov (United States)

    ElBatal, Fatma H; Morsi, Reham M; Ouis, Mona A; Marzouk, Samir Y

    2010-11-01

    UV-visible spectroscopic measurements of Ni-doped sodium phosphate glasses were carried out before and after successive gamma irradiation. The undoped glass reveals strong UV absorption originating from trace iron impurities. NiO-doped glasses show characteristic absorption bands due mainly to octahedral coordination of Ni(2+) ions. Gamma irradiation produces induced bands generated from intrinsic defects and extrinsic defects. The changes in the spectroscopic data are discussed in relation to the structural evolution caused by the changes in composition and coordination state of nickel ions. The change in the growth behaviour of the induced bands is related to the annihilation or approach saturation of these characteristic induced bands. Raman and E.S.R. spectroscopic measurements confirm the presence of nickel as Ni(2+) ions in octahedral state. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. 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

    2018-01-14

    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 Q n 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 3 B and 4 B 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.

  18. 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.

  19. Properties of sodium borosilicate glasses/Al2O3 sintered composites containing fluorides. Gan Fukkabutsu hokei san natoriumu garasu to alumina fukugo shoketsutai no bussei

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Bonggi; Yasui, I [The Univ. of Tokyo, Tokyo (Japan). Inst. of Industrial Science

    1993-06-01

    Glass/alumina sintered composites were synthesized from sodium borosilicate glass powder containing fluorides like AlF3 and NaF3, and Al2O3, and change in material properties was examined. Glass compositions of B2O3 and Na2O greatly affected the crystal phase and material properties. Nephelin crystal phase was extracted by the reaction of Na2O, NaF2, SiO2 and Al2O3 when B/Na<1. Coefficient of thermal expansion increased with the increase of Na/Si ratio. The residual amount of fluorides of sintered materials in nitrogen atmosphere was higher than that of air, and differed with the type of fluoride. The F[sup -] of NaF is bonded with Si of glass network and forms quiet stable glass structure, whereas, F[sup -] of AlF3 reacts with Si[sup 4+] forming SiF4 which is vaporized. Sintering temperature and dielectric constant of sintered materials containing fluoride was lower than the sintered materials without fluorides addition, however, at a sintering temperature range of 100 to 150[degree]C, it was inferred that this was because of the increase in voids due to SiF4 formed in the reaction. 16 refs., 17 figs., 3 tabs.

  20. Effect of Er{sub 2}O{sub 3} dopant on electrical and optical properties of potassium sodium niobate silicate glass-ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Yongsiri, Ploypailin [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Sirisoonthorn, Somnuk [National Metal and Materials Technology Center, Pathumthani 12120 (Thailand); Pengpat, Kamonpan, E-mail: kamonpan.p@cmu.ac.th [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Materials Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2015-09-15

    Highlights: • The KNN–SiO{sub 2} doped Er{sub 2}O{sub 3} glass-ceramics was prepared by incorporation method. • High dielectric constant (458.41 at 100 kHz) and low loss (0.0005) could be obtained. • TEM and SEM confirmed the existence of KNN crystals embedded in glass matrix. • The Er{sub 2}O{sub 3} dopant causes insignificant effect on modifying E{sub g} value. - Abstract: In this study, transparent glass-ceramics from potassium sodium niobate (KNN)-silicate glass system doped with erbium oxide (Er{sub 2}O{sub 3}) were successfully prepared by incorporation method. KNN was added in glass batches as heterogeneous nucleating agent. The KNN powder was mixed with SiO{sub 2} and Er{sub 2}O{sub 3} dopant with KNN and Er{sub 2}O{sub 3} content varied between 70–80 and 0.5–1.0 mol%, respectively. Each batch was subsequently melted at 1300 °C for 15 min in a platinum crucible using an electric furnace. The quenched glasses were then subjected to heat treatment at various temperatures for 4 h. XRD results showed that the prepared glass ceramics contained crystals of KNN solid solution. In contrary, dielectric constant (ϵ{sub r}) and dielectric loss (tan δ) were found to increase with increasing heat treatment temperature. Additionally, optical properties such as absorbance and energy band gap have been investigated.

  1. Stability of tranexamic acid in 0.9% sodium chloride, stored in type 1 glass vials and ethylene/propylene copolymer plastic containers.

    Science.gov (United States)

    McCluskey, Susan V; Sztajnkrycer, Matthew D; Jenkins, Donald A; Zietlow, Scott P; Berns, Kathleen S; Park, Myung S

    2014-01-01

    Tranexamic acid has recently been demonstrated to decrease all-cause mortality and deaths due to hemorrhage in trauma patients. The optimal administration of tranexamic acid is within one hour of injury, but not more than three hours from the time of injury. To aid with timely administration, a premixed solution of 1 gram tranexamic acid and 0.9% sodium chloride was proposed to be stocked as a medication in both the aeromedical transport helicopters and Emergency Department at Mayo Clinic Hospital--Rochester Saint Marys Campus. Since no published stability data exists for tranexamic acid diluted with 0.9% sodium chloride, this study was undertaken to determine the stability of tranexamic acid diluted with 0.9% sodium chloride while being stored in two types of containers. Stability was determined through the use of a stability-indicating high-performance liquid reverse phase chromatography assay, pH, and visual tests. Tranexamic acid solutions of 1 gram in 0.9% sodium chloride 65 mL were studied at predetermined intervals for 90 days in ethylene/propylene copolymer plastic containers, protected from light, and at both controlled room and refrigerated temperatures. Tranexamic acid solutions of 1 gram in 0.9% sodium chloride 50 mL were studied at predetermined intervals for 180 days in clear Type 1 borosilicate glass vials sealed with intact elastomeric, Flourotec-coated stoppers, stored protected from light at controlled room temperature. Solutions stored in the ethylene/propylene copolymer plastic containers at both storage temperatures maintained at least 98% of initial potency throughout the 90-day study period. Solutions stored in glass vials at controlled room temperature maintained at least 92% of initial potency throughout the 180-day study period. Visual and pH tests revealed stable, clear, colorless, and particulate-free solutions throughout the respective study periods.

  2. Uranium and sulphate values from carbonate leach process

    International Nuclear Information System (INIS)

    Berger, B.

    1983-01-01

    The process concerns the recovery of uraniferous and sulphur values from liquor resulting from the attack of sulphur containing uraniferous ores by an alkaline solution of sodium carbonate and/or bicarbonate. Ammonia is introduced into the liquor to convert any HCO 3 - to CO 3 2- . The neutralised liquor from this step is then contacted with an anion exchange resin to fix the uranium and sulphate ions, leaving a liquor containing ammonia, sodium carbonate and/or bicarbonate in solution. Uranium and sulphate ions are eluted with an ammonia carbonate and/or bicarbonate solution to yield a solution of ammonium uranyl carbonate complex and ammonium sulphate. The solution is subjected to thermal treatment until a suspension of precipitated ammonium uranate and/or diuranate is obtained in a solution of the ammonium sulphate. Carbon dioxide, ammonia and water vapor are driven off. The precipitated ammonium uranate and/or diuranate is then separated from the solution of ammonium sulphate and the precipitate is calcined to yield uranium trioxide and ammonia

  3. Contribution of sodium dodecyl sulphate and sodium lauric acid in ...

    Indian Academy of Sciences (India)

    Tao Q, He H P, Frost R L, Yuan P and Zhu J X 2009 Appl. Surf. Sci. 255 4334. 15. Pavan P C, Gomes G D A and Valim J B 1998 Microporous. Mesoporous Mater. 21 659. 16. Li P G, Lv F Z, Xu Z X, Qi G G and Zhang Y H 2013 J. Mater. Sci. 48 5437. 17. Saber O and Tagaya H 2003 J. Incl. Phenom. Macrocyclic. Chem.

  4. Study of the mixed alkali effect in lithium and sodium metaphosphate glass-forming liquids by photon correlation spectroscopy

    International Nuclear Information System (INIS)

    Changstrom, J R; Sidebottom, D L

    2008-01-01

    We report results of an extensive study of the structural relaxation occurring in mixed alkali metaphosphate liquids obtained by photon correlation spectroscopy. Values for the glass transition temperature, the fragility index, and the heterogeneity parameter (also known as the Kohlrausch exponent) are extracted from the measurements and are all shown to exhibit a mixed alkali effect wherein nonlinear variations with mixing occur. The depression in the glass transition temperature is shown to be the direct result of mechanical relaxations, present in the solid, which prematurely loosen the glass structure. A minimum in the fragility index is believed to be an artifact of the resulting depression of the glass transition temperature

  5. X-ray absorption spectroscopy on phosphoric-salt pellets. Determination of the geometric and electronic structure of metal-oxide doped sodium-phosphate glasses

    International Nuclear Information System (INIS)

    Brendebach, B.

    2004-02-01

    Sodium metaphosphate glasses doped with transition metal oxides show characteristic colors. X-ray absorption spectroscopy (XAS) investigations provide information whether the coloration stems from different electronic transitions or changes in the geometrical structure of the glasses. Even though the violet color of MnO y -doped glasses is considered as an evidence for Mn 3+ -ions, Mn K-XAS reveals that the majority of the manganese ions are in the oxidation state +II and have a mixed coordination of four and six oxygen atoms, respectively. The oxygen coordination around the nickel ions in NiO-doped glasses with different metall oxide concentrations is always six. The change of color from citreous to auburn with increasing nickel oxide content is attributed to a systematic change in the bonding characteristic from mainly ionic-like to a small but significant contribution of covalent-like bonding. Analysis of higher coordination shells provides no indication of the formation of metal oxide clusters. (orig.)

  6. New reddish-orange and greenish-yellow light emitting phosphors: Eu{sup 3+} and Tb{sup 3+}/Eu{sup 3+} in sodium germanate glass

    Energy Technology Data Exchange (ETDEWEB)

    Álvarez, E. [Departamento de Física, Universidad de Sonora (UNISON), Boulevard Luis Encinas y Rosales s/n, Hermosillo 83000, Sonora (Mexico); Zayas, Ma. E. [Departamento de Investigación en Física, Universidad de Sonora (UNISON), Boulevard Luis Encinas y Rosales s/n, Hermosillo 83000, Sonora (Mexico); Alvarado-Rivera, J. [Departamento de Física, Universidad de Sonora (UNISON), Boulevard Luis Encinas y Rosales s/n, Hermosillo 83000, Sonora (Mexico); Félix-Domínguez, F. [Departamento de Física, Universidad de Sonora (UNISON), Boulevard Luis Encinas y Rosales s/n, Hermosillo 83000, Sonora (Mexico); Centro de investigación en Materiales Avanzados, S.C. Miguel de Cervantes 120, Complejo industrial Chihuahua, Chihuahua 31109, Chihuahua (Mexico); Duarte-Zamorano, R.P. [Departamento de Física, Universidad de Sonora (UNISON), Boulevard Luis Encinas y Rosales s/n, Hermosillo 83000, Sonora (Mexico); Caldiño, U., E-mail: cald@xanum.uam.mx [Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, PO Box 55-534, México City 09340, Distrito Federal (Mexico)

    2014-09-15

    A spectroscopic analysis of sodium germanate glasses activated with Eu{sup 3+}, Tb{sup 3+} and Eu{sup 3+}/Tb{sup 3+} is performed from their photoluminescence spectra and decay times. In the Eu{sup 3+}-singly doped glass reddish-orange light emission, with x=0.64 and y=0.35 CIE1931 chromaticity coordinates, is obtained upon Eu{sup 3+} excitation at 393 nm. Such chromaticity coordinates are close to those (0.67, 0.33) proposed by the National Television Standard Committee for the red phosphor. When the sodium germanate glass is co-doped with Tb{sup 3+} and Eu{sup 3+} greenish-yellow light emission, with (0.41, 0.46) CIE1931 chromaticity coordinates, is obtained upon Tb{sup 3+} excitation at 344 nm. Such greenish-yellow luminescence is due mainly to the terbium {sup 5}D{sub 4}→{sup 7}F{sub 6,5} and europium {sup 5}D{sub 0}→{sup 7}F{sub 1,2} emissions, Eu{sup 3+} being sensitized by Tb{sup 3+} through a non-radiative energy transfer. The non-radiative nature of this energy transfer is inferred from the increase in the decay rate of the Tb{sup 3+} emission when the glass is co-doped with Eu{sup 3+}. From an analysis of the Tb{sup 3+} emission decay time curves it is inferred that such energy transfer might take place between Tb{sup 3+} and Eu{sup 3+} clusters through a short-range interaction mechanism. - Highlights: • Sodium germanate glasses are optically activated with Eu{sup 3+} (GNE) and Tb{sup 3+}/Eu{sup 3+} (GNTE). • Reddish-orange light (0.64, 0.35) is generated by GNE pumped with 393 nm light. • Greenish-yellow light (0.41, 0.46) is generated by GNTE pumped with 344 nm light. • Non-radiative energy transfer Tb{sup 3+}→Eu{sup 3+} takes place in GNTE.

  7. Effect of aluminum and silicon reactants and process parameters on glass-ceramic waste form characteristics for immobilization of high-level fluorinel-sodium calcined waste

    International Nuclear Information System (INIS)

    Vinjamuri, K.

    1993-06-01

    In this report, the effects of aluminum and silicon reactants, process soak time and the initial calcine particle size on glass-ceramic waste form characteristics for immobilization of the high-level fluorinel-sodium calcined waste stored at the Idaho Chemical Processing Plant (ICPP) are investigated. The waste form characteristics include density, total and normalized elemental leach rates, and microstructure. Glass-ceramic waste forms were prepared by hot isostatically pressing (HIPing) a pre-compacted mixture of pilot plant fluorinel-sodium calcine, Al, and Si metal powders at 1050 degrees C, 20,000 psi for 4 hours. One of the formulations with 2 wt % Al was HIPed for 4, 8, 16 and 24 hours at the same temperature and pressure. The calcine particle size range include as calcined particle size smaller than 600 μm (finer than -30 mesh, or 215 μm Mass Median Diameter, MMD) and 180 μm (finer than 80 mesh, or 49 μm MMD)

  8. Chemical durability of lead borosilicate glass matrix under simulated geological conditions

    International Nuclear Information System (INIS)

    Yalmali, Vrunda S.; Deshingkar, D.S.; Wattal, P.K.

    2002-03-01

    The lead borosilicate glass has been developed for vitrification of High Level Waste (HLW) stored at Trombay. This waste is contains especially high contents of sodium, uranium sulphate and iron. The glasses containing HLW are to be ultimately disposed into deep geological repositories. Long term leach rates under simulated geological conditions need to be evaluated for glass matrix. Studies were taken up to estimate the lead borosilicate glass WTR-62 matrix for chemical durability in presence of synthetic ground water. The leachant selected was based on composition of ground water sample near proposed repository site. In the first phase of these tests, the experiments were conducted for short duration of one and half month. The leaching experiments were conducted in presence of a) distilled water b) synthetic ground water c) synthetic ground water containing granite, bentonite and ferric oxide and d) synthetic ground water containing humic acid at 100 0 C. The leachate samples were analysed by pHmetry , ion chromatography and UV -VIS spectrophotometry. The normalised leach rates for lead borosilicate WTR- 62 glass matrix based on silica, boron and sulphate analyses of leachates were of the order of 10 -3 to 10 -5 gms/cm 2 /day for 45 days test period in presence of synthetic ground water as well as in presence of other materials likely to be present along with synthetic ground water. These rates are comparable to those of sodium borsilicate glass matrices reported in literature. It is known that the leach rates of glass matrix decrease with longer test durations due to formation of leached layer on its surface. The observed leach rates of lead borosilicate WTR- 62 glass matrix for 45 day tests under simulated geological conditions were found to be sufficiently encouraging to take up long term tests for evaluating its performances under repository conditions. (author)

  9. The effect of electron irradiation on the structure and iron speciation in sodium aluminum (iron) phosphate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Stefanovsky, S.V., E-mail: serge.stefanovsky@yandex.ru [Frumkin Institute of Physical Chemistry and Electrochemistry RAS (Russian Federation); Presniakov, I.A.; Sobolev, A.V.; Glazkova, I.S. [Lomonosov Moscow State University, Department of Chemistry (Russian Federation); Kadyko, M.I.; Stefanovsky, O.I. [Frumkin Institute of Physical Chemistry and Electrochemistry RAS (Russian Federation)

    2016-08-01

    The effect of 8 MeV electron irradiation on the structure of glasses in the series 40 Na{sub 2}O, (20-x) Al{sub 2}O{sub 3}, x Fe{sub 2}O{sub 3}, 40 P{sub 2}O{sub 5} (mol.%) and on the iron speciation in these samples was studied by FTIR and Mössbauer spectroscopic techniques. Irradiation up to a dose of 1.0 MGy has no appreciable effects on the character of the bonds within anionic motif of the glass network. Electron irradiation increases the fraction of aluminum in octahedral coordination. Iron in both unirradiated and irradiated glasses is present mainly as Fe(III) (60–75% of the total amount) in the glasses and partly as Fe(II) and the ratio of two forms remains constant up to a dose of 1.0 MGy.

  10. Comparative investigations of sodium arsenite, arsenic trioxide and cadmium sulphate in combination with gamma-radiation on apoptosis, micronuclei induction and DNA damage in a human lymphoblastoid cell line

    International Nuclear Information System (INIS)

    Hornhardt, Sabine; Gomolka, Maria; Walsh, Linda; Jung, Thomas

    2006-01-01

    In the field of radiation protection the combined exposure to radiation and other toxic agents is recognised as an important research area. To elucidate the basic mechanisms of simultaneous exposure, the interaction of the carcinogens and environmental toxicants cadmium and two arsenic compounds, arsenite and arsenic trioxide, in combination with gamma-radiation in human lymphoblastoid cells (TK6) were investigated. Gamma-radiation induced significant genotoxic effects such as micronuclei formation, DNA damage and apoptosis, whereas arsenic and cadmium had no significant effect on these indicators of cellular damage at non-toxic concentrations. However, in combination with gamma-radiation arsenic trioxide induced a more than additive apoptotic rate compared to the sum of the single effects. Here, the level of apoptotic cells was increased, in a dose-dependent way, up to two-fold compared to the irradiated control cells. Arsenite did not induce a significant additive effect at any of the concentrations or radiation doses tested. On the other hand, arsenic trioxide was less effective than arsenite in the induction of DNA protein cross-links. These data indicate that the two arsenic compounds interact through different pathways in the cell. Cadmium sulphate, like arsenite, had no significant effect on apoptosis in combination with gamma-radiation at low concentrations and, at high concentrations, even reduced the radiation-induced apoptosis. An additive effect on micronuclei induction was observed with 1 μM cadmium sulphate with an increase of up to 80% compared to the irradiated control cells. Toxic concentrations of cadmium and arsenic trioxide seemed to reduce micronuclei induction. The results presented here indicate that relatively low concentrations of arsenic and cadmium, close to those occurring in nature, may interfere with radiation effects. Differences in action of the two arsenic compounds were identified

  11. Thermal stability and Judd-Ofelt analysis of optical properties of Sm3+-doped sodium tellurite glasses

    Science.gov (United States)

    Mawlud, Saman Q.; Ameena, Mudhafar M.; Sahar, Md. Rahim; Mahraz, Zahra A. Said; Ahmed, Kasim Fawzy

    2017-09-01

    Series of glasses based on (70-x) TeO2 - 20Na2O - xSm2O3 (x=0, 0.3, 0.6, 1, 1.2, 1.5 mol%) have been prepared using melt-quenching technique. The nature of the glass has been confirmed using X-ray diffraction; it is found that the glass samples are amorphous in nature. The thermal stability of the glass has been determined by means of Differential Thermal Analysis (DTA). From the DTA curve, the glass transition temperature (Tg), crystallization temperature (Tc) and melting temperature (Tm) have been identified and thermal stability is also calculated. The absorption properties of these samples are obtained by using UV-Visible-NIR spectrometer, the recorded absorption spectra exhibit nine absorption transition bands peaks corresponding to the transitions from ground level 6H5/2→6P3/2, 4I11/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2 and 6F1/2. The emission characteristic of this glass is characterized using Photoluminescence (PL) spectroscopy at excited wavelength 404 nm, the emission spectra consisted of four emission bands at 561.95 nm, 598.69 nm, 643.77 nm and 704.56 nm which were assigned as a transition 4G5/2→6H5/2, 6H7/2, 6H9/2 and 6H11/2 respectively. From f-f intensity model the experimental oscillator strengths, fexp and theoretical oscillator strength fcal were calculated. Using Judd-Ofelt theory and fit process of least square, the phenomenological intensity parameters Ωλ (λ=2,4,6) were obtained, In order to evaluate potential applications of Sm3+ ions in telluride glasses, the spectroscopic parameters: transition probability AR, branching ratio Br, radiative life time τr, emission pick cross section σλ for each band were calculated. The comparative studies with other Sm3+ doped different glasses showed that present glasses could be a potential candidate for lasers.

  12. Copper sulphate poisoning in horses

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, M

    1975-01-01

    In the archives of the Clinic for Internal Diseases of Domestic Animals at the Veterinary Faculty of Zagreb University some thirty cases of horse disease diagnosed as copper sulphate poisoning were noted. The data correspond in many respects to the clinical findings of copper sulphate poisoning in other domestic animals. A series of experimental horse poisonings were undertaken in order to determine the toxicity of copper sulphate. The research results are as follows: Horses are sensitive to copper sulphate. Even a single application of 0.125 g/kg body weight in 1% concentration by means of incubation into the stomach causes stomach and gut disturbances and other poisoning symptoms. Poisoning occurs in two types: acute and chronic. The former appears after one to three applications of copper sulphate solution and is characterized by gastroenteritis, haemolysis, jaundice and haemoglobinuria with signs of consecutive damage of kidney, liver and other organs. The disease, from the first application to death lasts for two weeks. Chronic poisoning is caused by ingestion of dry copper sulphate in food (1% solution dried on hay or clover) for two or more months. There are chronic disturbances of stomach and gut and loss of weight, and consecutive (three to four) haemolytic crises similar to those of acute poisoning. From the beginning of poisoning to death six or more months can elapse.

  13. Spectroscopic investigations of OH- influence on near-infrared fluorescence quenching of Yb3+/Tm3+ co-doped sodium-metaphosphate glasses

    International Nuclear Information System (INIS)

    Terra, I.A.A.; Camargo, A.S.S. de; Terrile, M.C.; Nunes, L.A.O.

    2008-01-01

    Energy transfer processes were studied in two sets of Yb 3+ and Tm 3+ co-doped sodium-metaphosphate glasses, prepared in air and nitrogen atmospheres. Using Foerster, Dexter, and Miyakawa theoretical models, the energy transfer parameters were calculated. The main ion-ion energy transfer processes analyzed were energy migration among Yb 3+ ions, cross-relaxations between Yb 3+ and Tm 3+ ions, and interactions with OH - radicals. The results indicated that Yb→Tm energy transfer favors 1.8 μm emissions, and there is no evidence of concentration quenching up to 2% Tm 2 O 3 doping. As expected, samples prepared in nitrogen atmosphere present higher fluorescence quantum efficiency than those prepared in air, and this feature is specially noted in the near-infrared region, where the interaction with the OH - radicals is more pronounced

  14. Determination of optimum mixing time for raw materials with the tracer method in the glass industry

    Energy Technology Data Exchange (ETDEWEB)

    Gallyas, M; Gemesi, J; Kurinka, J

    1983-02-01

    The authors explain how the optimum mixing time for the raw materials for glass manufacture can be determined with the aid of the radioactive tracer method. Basing themselves on measurements, they indicate the change in the degree of mixing of the individual components (soda (Na-24), sodium sulphate, coke (La-140) and bone meal (P-32) as a function of mixing time. The optimum degree of mixing and mixing time for dry and for wet mixing are determined. Finally, data for determining the permissible storage time of the mixture are given.

  15. Performance of cement solidification with barium for high activity liquid waste including sulphate

    International Nuclear Information System (INIS)

    Waki, Toshikazu; Yamada, Motoyuki; Horikawa, Yoshihiko; Kaneko, Masaaki; Saso, Michitaka; Haruguchi, Yoshiko; Yamashita, Yu; Sakai, Hitoshi

    2009-01-01

    The target liquid waste to be solidified is generated from PWR primary loop spent resin treatment with sulphate acid, so, its main constituent is sodium sulphate and the activity of this liquid is relatively high. Waste form of this liquid waste is considered to be a candidate for the subsurface disposal. The disposed waste including sulphate is anticipated to rise a concentration of sulphate ion in the ground water around the disposal facility and it may cause degradation of materials such as cement and bentonite layer and comprise the disposal facility. There could be two approaches to avoid this problem, the strong design of the disposal facility and the minimization of sulphaste ion migration from the solidified waste. In this study, the latter approach was examined. In order to keep the low concentration of sulphate ion in the ground water, it is effective to make barium sulphate by adding barium compound into the liquid waste in solidification. However, adding equivalent amount of barium compound with sulphate ion causes difficulty of mixing, because production of barium sulphate causes high viscosity. In this study, mixing condition after and before adding cement into the liquid waste was estimated. The mixing condition was set with consideration to keep anion concentration low in the ground water and of mixing easily enough in practical operation. Long term leaching behavior of the simulated solidified waste was also analyzed by PHREEQC. And the concentration of the constitution affected to the disposal facility was estimated be low enough in the ground water. (author)

  16. Glass transition dynamics and conductivity scaling in ionic deep eutectic solvents: The case of (acetamide + lithium nitrate/sodium thiocyanate) melts

    Energy Technology Data Exchange (ETDEWEB)

    Tripathy, Satya N., E-mail: satyanarayantripathy@gmail.com; Wojnarowska, Zaneta; Knapik, Justyna; Paluch, Marian [Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Silesian Center for Education and Interdisciplinary Research, 75 Pulku Piechoty 1A, 41-500 Chorzow (Poland); Shirota, Hideaki [Department of Nanomaterial Science and Department of Chemistry, Chiba University, 1-33 Yayoi, Inage-ku, Chiba 263-8522 (Japan); Biswas, Ranjit [Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake, Kolkata 700098 (India)

    2015-05-14

    A detailed investigation on the molecular dynamics of ionic deep eutectic solvents (acetamide + lithium nitrate/sodium thiocyanate) is reported. The study was carried out employing dielectric relaxation spectroscopy covering seven decades in frequency (10{sup −1}-10{sup 6} Hz) and in a wide temperature range from 373 K down to 173 K, accessing the dynamic observables both in liquid and glassy state. The dielectric response of the ionic system has been presented in the dynamic window of modulus formalism to understand the conductivity relaxation and its possible connection to the origin of localized motion. Two secondary relaxation processes appear below glass transition temperature. Our findings provide suitable interpretation on the nature of secondary Johari-Goldstein process describing the ion translation and orientation of dipoles in a combined approach using Ngai’s coupling model. A nearly constant loss feature is witnessed at shorter times/lower temperatures. We also discuss the ac conductivity scaling behavior using Summerfield approach and random free energy barrier model which establish the time-temperature superposition principle. These experimental observations have fundamental importance on theoretical elucidation of the conductivity relaxation and glass transition phenomena in molten ionic conductors.

  17. Role of valence state of vanadium ions on structural and spectroscopic properties of sodium lead bismuth silicate glass ceramics

    Science.gov (United States)

    Rao, M. V. Sambasiva; Tirupataiah, Ch.; Kumar, A. Suneel; Narendrudu, T.; Suresh, S.; Ram, G. Chinna; Rao, D. Krishna

    2018-04-01

    Glass ceramics with composition 10Na2O- 30PbO-10Bi2O3-(50-x)SiO2: xV2O5 (0 ≤ x ≤ 5) were synthesized by melt quenching and heat treatment method. XRD and SEM studies have indicated that the samples contain well defined and randomly distributed grains of different crystalline phases. Optical absorption spectra of these samples exhibited two absorption bands at 629 and 835 nm which are the characteristics of V4+ ions. The EPR spectra of these samples have exhibited well resolved hyperfine structure consisting of sixteen-eight parallel and eight perpendicular lines with a raise in their intensity with an increase in the content of V2O5 up to 3 mol% indicates the increase of redox ratio V4+/V5+ in the glass ceramic matrix.

  18. Link between optical spectra, crystal-field parameters, and local environments of Eu3+ ions in Eu2O3-doped sodium disilicate glass

    International Nuclear Information System (INIS)

    Qin, T.; Mountjoy, G.; Afify, N. D.; Reid, M. F.; Yeung, Y. Y.; Speghini, A.; Bettinelli, M.

    2011-01-01

    Rare-earth-doped glasses are key materials for optical technology due to the luminescent properties of 4f n ions. The crystal-field model describes the effect of local environment on transitions between 4f electrons. We present a detailed modeling study of the optical spectra of sodium disilicate glass, 33Na 2 O·67SiO 2 , doped with 0.2% and 1.0 mol%Eu 2 O 3 . This study uses very large molecular dynamics models with up to 100 Eu 3+ ions, the superposition model for covalent and overlap effects on crystal-field parameters, and realistic values for homogeneous linewidth broadening. The simulated spectra are in reasonable agreement with experiment. The trends in 7 F J energy levels across different Eu 3+ ion sites have been examined and a very detailed analysis is presented that looks at how features of the spectra are related to features of the local environment of Eu 3+ ions. Increasing the crystal-field strength S total causes the 7 F 0 energy level to decrease and causes the splitting of 7 F J manifolds to increase, and this is due to increasing mixing of 4f wave functions. To a reasonable approximation the crystal-field strength components S k depend on angular positions of ligands independently of distances to ligands. The former are seen to be more significant in determining S k , which are closely related to the rotationally invariant bond-orientational order parameters Q k . The values of S 2 are approximately linear in Q 2 , and the values of Q 2 are higher for fivefold than sixfold coordinated rare-earth ions. These results can be of importance for efforts to enhance the local environment of rare-earth ions in oxide glasses for optical applications.

  19. Study of the sulphate expansion phenomenon in concrete: behaviour of the cemented radioactive wastes containing sulphate

    International Nuclear Information System (INIS)

    Li, Guanshu

    1994-01-01

    Sulphate attack is one of the major degradation processes of concrete. It is especially important in storing cemented radioactive wastes containing sulphate. In this thesis, we have thoroughly investigated the degradation mechanisms of cemented radioactive wastes by sulphate. The CaO-Al 2 O 3 -SO 3 -H 2 O systems with and without alkalis are studied. For the system without alkalis, experimental results show that it is the formation of a secondary ettringite under external water supply by steric effect that causes the expansion. For the system with alkalis, the ettringite does not appear while a new mineral called 'U', a sodium-substituted AFm phase is detected. This phase is shown to be responsible for the expansion and destruction of the specimens. The conditions for the formation, the product of solubility and many means of its synthesis are discussed, and a complete list of the inter-reticular distances file is given. The behaviour of the different types of cemented wastes containing sulphate are then studied with a special focus on the U phase on entity which was heretofore very little understood. The following three hypothetical mechanisms of sulphate expansion are proposed: the formation of the secondary U phase, the transformation of the U phase to the ettringite and the topochemical hydration of thenardite into mirabilite. Experiments on a simplified system have demonstrated clearly that the formation of the secondary U phase can induce enormous expansion by steric effect, this justifying the first assumption. Simulation by the mass and volume balances is carried out thereafter and enables us to estimate the expansion induced by the formation of the secondary U phase in the cemented wastes. The second assumption is also well verified by a series of leaching tests in different solutions on mixtures containing the U phase. On the basis of the analysis of the specimens under leaching, it has been assumed that the expansion is associated with the

  20. Sulphate reduction experiment: SURE-1

    International Nuclear Information System (INIS)

    Pedersen, K.; Arlinger, J.; Bengtsson, A.; Edlund, J.; Eriksson, L.; Hallbeck, L.; Johansson, J.; Paeaejaervi, A.; Rabe, L.

    2013-11-01

    It was previously concluded that opposing gradients of sulphate and methane, observations of 16S rDNA sequences displaying great similarity to those of anaerobic methane-oxidizing Archaea, and a peak in sulphide concentration in groundwater from a depth of 250-350 m in Olkiluoto, Finland, indicated proper conditions for methane oxidation with sulphate. In the present research (SURE-1), pressure-resistant, gas-tight circulating systems were constructed to enable the investigation of attached and unattached anaerobic microbial populations from a depth of 327 m in Olkiluoto under in situ pressure (2.4 MPa), diversity, dissolved gas, and hydrochemical conditions of groundwater station ONKPVA6. Three parallel flow cell cabinets were configured to allow observation of the influence on microbial metabolic activity of 11 mM methane, 11 mM methane plus 10 mM H 2 , or 2.1 mM O 2 plus 7.9 mM N 2 (i.e., air). The concentrations of these gases and of organic acids and carbon, sulphur chemistry, pH and E h , ATP, numbers of cultivable microorganisms, and total numbers of cells and bacteriophages were subsequently recorded under batch conditions for 105 d. The system containing H 2 and methane displayed microbial reduction of 0.7 mM sulphate to sulphide, while the system containing only methane produced 0.2 mM reduced sulphate. The system containing added air became inhibited and displayed no signs of microbial activity. Added H 2 and methane induced increasing numbers of lysogenic bacteriophages per cell. It appears possible that a microbial anaerobic methane-oxidizing process coupled to acetate formation and sulphate reduction may be ongoing in aquifers at a depth of 250-350 m in Olkiluoto, but clear evidence of such an AOM process was not obtained. (orig.)

  1. Sulphate reduction experiment: SURE-1

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, K.; Arlinger, J.; Bengtsson, A.; Edlund, J.; Eriksson, L.; Hallbeck, L.; Johansson, J.; Paeaejaervi, A.; Rabe, L. [Microbial Analytics Sweden AB, Moelnlycke (Sweden)

    2013-11-15

    It was previously concluded that opposing gradients of sulphate and methane, observations of 16S rDNA sequences displaying great similarity to those of anaerobic methane-oxidizing Archaea, and a peak in sulphide concentration in groundwater from a depth of 250-350 m in Olkiluoto, Finland, indicated proper conditions for methane oxidation with sulphate. In the present research (SURE-1), pressure-resistant, gas-tight circulating systems were constructed to enable the investigation of attached and unattached anaerobic microbial populations from a depth of 327 m in Olkiluoto under in situ pressure (2.4 MPa), diversity, dissolved gas, and hydrochemical conditions of groundwater station ONKPVA6. Three parallel flow cell cabinets were configured to allow observation of the influence on microbial metabolic activity of 11 mM methane, 11 mM methane plus 10 mM H{sub 2}, or 2.1 mM O{sub 2} plus 7.9 mM N{sub 2} (i.e., air). The concentrations of these gases and of organic acids and carbon, sulphur chemistry, pH and E{sub h}, ATP, numbers of cultivable microorganisms, and total numbers of cells and bacteriophages were subsequently recorded under batch conditions for 105 d. The system containing H{sub 2} and methane displayed microbial reduction of 0.7 mM sulphate to sulphide, while the system containing only methane produced 0.2 mM reduced sulphate. The system containing added air became inhibited and displayed no signs of microbial activity. Added H{sub 2} and methane induced increasing numbers of lysogenic bacteriophages per cell. It appears possible that a microbial anaerobic methane-oxidizing process coupled to acetate formation and sulphate reduction may be ongoing in aquifers at a depth of 250-350 m in Olkiluoto, but clear evidence of such an AOM process was not obtained. (orig.)

  2. EPR study of gamma irradiated N-methyl taurine (C 3H 9NO 3S) and sodium hydrogen sulphate monohydrate (NaHSO 3·H 2O) single crystals

    Science.gov (United States)

    Yıldırım, İlkay; Karabulut, Bünyamin

    2011-03-01

    EPR study of gamma irradiated C 3H 9NO 3S and NaHSO 3.H 2O single crystals have been carried out at room temperature. There is one site for the radicals in C 3H 9NO 3S and two magnetically distinct sites for the radicals in NaHSO 3. The observed lines in the EPR spectra have been attributed to the species of SO3- and RH radicals for N-methyl taurine, and to the SO3- and OH radicals for sodium hydrogen sulfate monohydrate single crystals. The principal values of the g for SO3-, the hyperfine values of RH and OH proton splitting have been calculated and discussed.

  3. Radioprotective effects of dextran sulphate in mice

    International Nuclear Information System (INIS)

    Vacek, A.; Bartonickova, A.; Rotkovska, D.; Palyga, G.F.; Zhukova, N.A.

    1981-01-01

    Influence of a single i.p. injection of dextran sulphate on radiosensitivity of mice was investigated. The administration of dextran sulphate 24, 48 and 72 hours prior to irradiation increased formation of endogenous colonies of the hemopoietic tissue on the surface of the spleen. DRF calculated from an equieffective exposure for 5 colonies was 1.96 when dextran sulphate was administered 24 hours before irradiation, and 2.25 when dextran sulphate was administered 72 hours before irradiation. The radioprotective effects of dextran sulphate were manifested also in the survival of animals exposed to lethal doses of short-termed as well as long-termed gamma radiation. (orig.) [de

  4. Magnesium sulphate for fetal neuroprotection

    DEFF Research Database (Denmark)

    Bickford, Celeste D; Magee, Laura A; Mitton, Craig

    2013-01-01

    of cerebral palsy (CP) averted and quality-adjusted life years (QALYs). RESULTS: From a health system and a societal perspective, respectively, a savings of $2,242 and $112,602 is obtained for each QALY gained and a savings of $30,942 and $1,554,198 is obtained for each case of CP averted when magnesium......BACKGROUND: The aim of this study was to assess the cost-effectiveness of administering magnesium sulphate to patients in whom preterm birth at ... sensitivity analyses were used to compare the administration of magnesium sulphate with the alternative of no treatment. Two separate cost perspectives were utilized in this series of analyses: a health system and a societal perspective. In addition, two separate measures of effectiveness were utilized: cases...

  5. Intoxication experiments with beryllium sulphate

    International Nuclear Information System (INIS)

    Bucurescu, I.; Stan, T.

    1990-01-01

    The changes in the particular number of animals in two groups of 40 rats each subjected to intoxication experiments with beryllium sulphate was investigated. The two investigations had very different characteristics. In the case of chronic intoxication there was a marked lethality over given time intervals. In the case of subacute intoxication the number of animals decreased with time. It was found empirically that this change can be described by an exponential relationship which lends itself to statistical interpretation. (author)

  6. Preparation of Magnetite Nanocrystals from Ferrous Sulphate Solution

    International Nuclear Information System (INIS)

    Cho Yu Mon; Tint Tint Kywe; Moe Moe Kyaw

    2010-12-01

    Magnetite (Fe3O4) nanoparticle were prepared by hydrothermal process in two ways, which would be used for production of copier toner.In this investigation, the first process was made from ferrous sulphate (FeSO4 . 7H2O) by using 10 M sodium hydroxide solution. In this method, magnetite nanoparticles were prepared by changing aeration time from 1 to 3 hr and heated at 90C for 15 min. The alternative process was carried out from ferrous sulphate (FeSO4.7H2O) by using 6.6 M sodium hydroxide solution and sodium silicate solution.Magnetite (black iron oxide) was synthesized by using different aeration times and reaction times. Aeration time was changed from 1 to 2 hr and reaction time was changed from 1 to 5.5 hr at 85 C. The magnetites obtained were examined by X-ray Diffraction (XRD) analysis and Scanning Electron Microscopy (SEM) technique. The average particle size range of magnetite nanoprticles were 90-120 nm and 120-150 nm in each process. The maximum yied percentages of magnetite based on FeSO4 in both processing were found to be 46.30% and 60.72%. The precent yields of magnetite in both preparation based on theoretical yields were 91.02% and 94.83% respectively.

  7. Structural change of NaO1/2-WO3-NbO5/2-LaO3/2-PO5/2 glass induced by electrochemical substitution of sodium ions with protons.

    Science.gov (United States)

    Ishiyama, Tomohiro; Yamaguchi, Takuya; Nishii, Junji; Yamashita, Toshiharu; Kawazoe, Hiroshi; Kuwata, Naoaki; Kawamura, Junichi; Omata, Takahisa

    2015-05-28

    Structural changes of 35NaO1/2-1WO3-8NbO5/2-5LaO3/2-51PO5/2 glass (1W-glass) before and after the electrochemical substitution of sodium ions with protons by alkali-proton substitution (APS) are studied by Raman and (31)P magic-angle spinning nuclear magnetic resonance (MAS-NMR) spectroscopies. The glass before APS consists of (PO3(-))8.6(P2O7(4-)) chains on average and the terminal Q(1) units (-O-PO3(3-)) are bound to MO6 octahedra (M denotes niobium or tungsten) through P-O-M bonds. Some non-bridging oxygens (NBOs) in the MO6 octahedra are present in addition to the bridging oxygens (BOs) in P-O-M bonds. APS induces fragmentation of the phosphate chains because the average chain length decreases to (PO3(-))3.7(P2O7(4-)) after APS, despite the total number of modifier cations of sodium and lanthanum ions and protons being unaffected by APS. This fragmentation is induced by some of the NBOs in the MO6 octahedra before APS, changing to BOs of the newly formed M-O-P bonds after APS, because of the preferential formation of P-OH bonds over M-OH ones in the present glass. We show that APS under the conditions used here is not a simple substitution of sodium ions with protons, but it is accompanied by the structural relaxation of the glass to stabilize the injected protons.

  8. Thermodynamic analysis of dust sulphation reactions

    Energy Technology Data Exchange (ETDEWEB)

    Yang Yongxiang; Jokilaakso, A.

    1997-12-31

    Sulphation reactions of metal oxides with SO{sub 2} and O. or SO{sub 3} play significant roles in sulphation roasting of sulphide and oxide minerals as well as in desulphurisation process of combustion gases. In metallurgical waste-heat boilers for sulphide smelting, the sulphation of the oxidic flue dust in the atmosphere containing sulphur oxides is an unavoidable process, and the sulphation reactions have to be guided in a controlled way in the proper parts of the gas handling equipment. In this report, some thermodynamic analyses were conducted for the oxide sulphation reactions in relation to sulphide smelting processes. The phase stability of Me-S-O systems especially for oxides - sulphates equilibrium was studied under different thermodynamic conditions of gas compositions and temperatures. The sulphate stability was analysed for an example of gas compositions in the copper flash smelter of Outokumpu Harjavalta Metals Oy, in relation to temperature. In the report, most of the information was from literature. Moreover, a number of thermodynamic computations were carried out with the HSC program, and the constructed phase stability diagrams were compared with those from the literature whenever possible. The maximum temperatures for stable sulphates under normal operating conditions of the waste-heat boilers in sulphide smelting processes were obtained. This report will serve as the basis for the kinetic studies of the sulphation reactions and the sulphation reaction modelling in pyrometallurgical processes. (orig.) SULA 2 Programme. 36 refs.

  9. Sulphate reduction in the Aespoe HRL tunnel

    International Nuclear Information System (INIS)

    Gustafson, G.; Pedersen, K.; Tullborg, E.L.; Wallin, B.; Wikberg, P.

    1995-12-01

    Evidence and indications of sulphate reduction based on geological, hydrogeological, groundwater, isotope and microbial data gathered in and around the Aespoe Hard Rock Laboratory tunnel have been evaluated. This integrated investigation showed that sulphate reduction had taken place in the past but is most likely also an ongoing process. Anaerobic sulphate-reducing bacteria can live in marine sediments, in the tunnel sections under the sea and in deep groundwaters, since there is no access to oxygen. The sulphate-reducing bacteria seem to thrive when the Cl - concentration of the groundwater is 4000-6000 mg/l. Sulphate reduction is an in situ process but the resulting hydrogen-sulphide rich water can be transported to other locations. A more vigorous sulphate reduction takes place when the organic content in the groundwater is high (>10 mg/l DOC) which is the case in the sediments and in the groundwaters under the sea. Some bacteria use hydrogen as an electron donor instead of organic carbon and can therefore live in deep environments where access to organic material is limited. The sulphate-reducing bacteria seem to adapt to changing flow situations caused by the tunnel construction relatively fast. Sulphate reduction seems to have occurred and will probably occur where conditions are favourable for the sulphate-reducing bacteria such as anaerobic brackish groundwater with dissolved sulphate and organic carbon or hydrogen. 59 refs, 37 figs, 6 tabs

  10. Prediction models of mechanical properties for pet-mortar composite in sodium sulphateaggressive mediums

    OpenAIRE

    Kazi Tani Nabil; Benosman A.S.; Senhadji Y.; Taïbi H.; Mouli M.; Belbachir M.

    2018-01-01

    In this research, an investigation was carried out on the effect of sodium sulphate attack on the durability of composites produced with waste polyethylene terephthalate (PET). Experiments were accomplished on limestone sand and cement mortars where the blended Portland cement was partially replaced by various volume fractions of waste PET particles (6%, 12% and 17%). The test solutions used to supply the sulphate ions and cations were 5%sodium sulphate solution. Compressive strengths measure...

  11. Removal of sulphates from waste waters by sulphate-reducing bacteria

    Directory of Open Access Journals (Sweden)

    Luptáková Alena

    2002-03-01

    Full Text Available are present in almost all types of water, usually as a simple anion SO42-. The sulphates together with hydrogencarbonates and chlorides are principal anions in natural waters. In typical underground and surface waters, the concentration of sulphates is in the range from ten to hundreds milligrams per litre.Nowadays, the importance of the control of sulphate concentration in waste waters increases. According to the Slovak legislation the limit concentration of sulphates in surface and drinking waters is 250 mg.l-1 . In rivers the contents of sulphates increases mainly by the discharge of waste waters, which are coming mainly from chemical, textile, metallurgical, pharmaceutical, paper and mining industry. The concentration of sulphates in these waters is in the order of grams per litre.Many technologies for the sulphates removal from waste waters exist, including biologico-chemical processes. The principle of one of these methods is the reduction of sulphates by sulphate-reducing bacteria to hydrogen-sulphide.The objective of this work was to study the effect of initial sulphates concentration on the activity of anaerobic sulphate reducers as well as the kinetics of the anaerobic sulphate reduction. The batch reactor was used at temperature of 30°C and pH 7,5. Lactate was used as the carbon source.

  12. Performance of Electrocoagulation Process for Removal of Sulphate Ion from Aqueous Environments Using Plate Aluminum Electrodes

    Directory of Open Access Journals (Sweden)

    a.h Mahvi

    2012-05-01

    Full Text Available

    Background and Objectives: Sulphate ion is one of the main ions available in natural and waste water. The high rate of sulphate in drinking water causes health problems such as irritation and digestive problems and makes water taste bitter. The purpose of this study was to assess the efficiency of sulphate ion removal from drinking water through Electrocogualation process (EC using plate aluminum electrodes. Methods: This study was conducted as a pilot plant using one glass tank in the volume of 1.3liter containing 6 plate aluminum electrodes. These electrodes were attached to a power supply in a mono-polar and parallel arrangement in order to switch the alternating current to the direct one. That is, each electrode was attached to positive and negative poles directly and alternately. The tank was filled with synthetic water containing sulphate ion with the concentration of 350 & 700mg/L. Percentage of sulphate ion removal in potential range of 10, 20 and 30 V, reaction times of 40, 20 and 60min and pH 7.0, 3.0 & 11.0 were measured. Results: In this study the maximum efficiency of sulphate ion removal was in the electrical potential of 30 V, reaction time of 60min and pH 11.0. With increase of ion concentration, the time needed to achieve a suitable efficiency of removal increased, that is, it indicated the direct effect of pH and difference of electrical potential on removal of sulphate ion through EC process. Conclusion: The results of this research show that Electrocogualation technology can be introduced as a suitable and promising technique to remove sulphate ion from aqueous environments using plate aluminum electrodes.

     

  13. Performance of Electrocoagulation Process for Removal of Sulphate Ion from Aqueous Environments Using Plate Aluminum Electrodes

    Directory of Open Access Journals (Sweden)

    Rajabizadeh A.

    2010-09-01

    Full Text Available Background and Objectives: Sulphate ion is one of the main ions available in natural and waste water. The high rate of sulphate in drinking water causes health problems such as irritation and digestive problems and makes water taste bitter. The purpose of this study was to assess the efficiency of sulphate ion removal from drinking water through Electrocogualation process (EC using plate aluminum electrodes.Methods: This study was conducted as a pilot plant using one glass tank in the volume of 1.3liter containing 6 plate aluminum electrodes. These electrodes were attached to a power supply in a mono-polar and parallel arrangement in order to switch the alternating current to the direct one. That is, each electrode was attached to positive and negative poles directly and alternately. The tank was filled with synthetic water containing sulphate ion with the concentration of 350 & 700mg/L. Percentage of sulphate ion removal in potential range of 10, 20 and 30 V, reaction times of 40, 20 and 60min and pH 7.0, 3.0 & 11.0 were measured.Results: In this study the maximum efficiency of sulphate ion removal was in the electrical potential of 30 V, reaction time of 60min and pH 11.0. With increase of ion concentration, the time needed to achieve a suitable efficiency of removal increased, that is, it indicated the direct effect of pH and difference of electrical potential on removal of sulphate ion through EC process.Conclusion: The results of this research show that Electrocogualation technology can be introduced as a suitable and promising technique to remove sulphate ion from aqueous environments using plate aluminum electrodes.

  14. Extraction of sulphates by long chain amines

    International Nuclear Information System (INIS)

    Boirie, Ch.

    1959-05-01

    The extraction of sulphuric acid by long chain amines in organic solution has been studied with a view to determining the value of the stability constants of the amine sulphates and bi-sulphates formed. We have concentrated chiefly on uranium sulphate and thorium sulphate. The formulae of the complexes extractable with amines have been established, as well as the corresponding dissociation constants. We have observed that for uranium sulphate the formula of the complex depends only on the nature of the amine, whereas for thorium this formula varies with the amine structure. From the formulae determined and the value of the constants calculated, we have been able to establish the best conditions for uranium and thorium extraction and also for a separation of these two elements. Finally we propose an application of this study to the determination of uranium in ores, where the separation of uranium by this method is particularly easy and complete. (author) [fr

  15. Anisotropy in elastic properties of lithium sodium sulphate

    Indian Academy of Sciences (India)

    The double sulfate family of (ABSO4) where A and B are alkali metal cations, is the object of great interest owing to the complexity and richness of its sequence of phase transition induced by temperature variation. A new sulfate salt characterized by the presence of water molecule in the unit cell with the chemical formula, ...

  16. Sodium-dodecyl-sulphate-assisted synthesis of Ni nanoparticles ...

    Indian Academy of Sciences (India)

    2017-11-20

    Nov 20, 2017 ... the SDS concentration, while at high concentration (mole ratio of SDS:Ni(acac)2 = 4:1), the small ... Over the last decades, synthesis of magnetic metallic ... pared nickel nanoparticles (3.7 nm) via hydrothermal method.

  17. X-ray absorption spectroscopy on phosphoric-salt pellets. Determination of the geometric and electronic structure of metal-oxide doped sodium-phosphate glasses; Roentgenabsorptionsspektroskopie an Phosphorsalzperlen. Bestimmung der geometrischen und elektronischen Struktur von metalloxid-dotierten Natriumphosphatglaesern

    Energy Technology Data Exchange (ETDEWEB)

    Brendebach, B.

    2004-02-01

    Sodium metaphosphate glasses doped with transition metal oxides show characteristic colors. X-ray absorption spectroscopy (XAS) investigations provide information whether the coloration stems from different electronic transitions or changes in the geometrical structure of the glasses. Even though the violet color of MnO{sub y}-doped glasses is considered as an evidence for Mn{sup 3+}-ions, Mn K-XAS reveals that the majority of the manganese ions are in the oxidation state +II and have a mixed coordination of four and six oxygen atoms, respectively. The oxygen coordination around the nickel ions in NiO-doped glasses with different metall oxide concentrations is always six. The change of color from citreous to auburn with increasing nickel oxide content is attributed to a systematic change in the bonding characteristic from mainly ionic-like to a small but significant contribution of covalent-like bonding. Analysis of higher coordination shells provides no indication of the formation of metal oxide clusters. (orig.)

  18. Effect of various additives on microstructure, mechanical properties, and in vitro bioactivity of sodium oxide-calcium oxide-silica-phosphorus pentoxide glass-ceramics.

    Science.gov (United States)

    Li, H C; Wang, D G; Hu, J H; Chen, C Z

    2013-09-01

    The partial substitution of MgO, TiO2, or CaF2 for CaO in the Na2O-CaO-SiO2-P2O5 (45S5) system was conducted by the sol-gel method and a comparative study on structural, mechanical properties, and bioactivity of the glasses was reported. Based on thermogravimetric and differential thermal analysis, the gels were sintered with a suitable heat treatment procedure. The glass-ceramic properties were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and so on, and the bioactivity of the glass-ceramic was evaluated by in vitro assays in simulated body fluid (SBF). Results indicate that with the partial substitution of MgO, TiO2, CaF2 for CaO in glass composition, the mechanical properties of the glass-ceramics have been significantly improved. Furthermore, CaF2 promotes glass crystallization and the crystallization does not inhibit the glass-ceramic bioactivity. All samples possess bioactivity; however, the bioactivity of these glass-ceramics is quite different. Compared with 45S5, the introduction of MgO decreases the ability of apatite induction. The addition of TiO2 does not significantly improve the bioactivity, and the replacement of CaO by CaF2 shows a higher bioactivity. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Sulphate deposition by precipitation into Lake Ontario

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, R W; Whelpdale, D M

    1973-01-01

    Measurements of sulphate concentration in precipitation from individual snow storms of several hours duration in the western Lake Ontario region indicate that approximately 9-66 mg/M/sub 2/ of SO/sub 4//sup 2 -/ is being deposited into the lake per storm. This amount is up to several times more than daily average values over long periods found by other workers. Using a mean sulphate concentration of 4 mg/l and an annual accumulation of precipitation of 760 mm, the yearly sulphate deposition by precipitation is about 0.1% of the total mass of sulphate in the lake; however, more significantly, it is of the same order of magnitude as that discharged directly into the lake by industry.

  20. Diffusion of cesium in sodium-borosilicate glasses for nuclear waste immobilisation. Diffusie van cesium in natrium borosilicaat glazen voor het immobiliseren van radioaktief afval

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, F.J.J.G.; Sengers, E.G.F. (Keuring van Electrotechnische Materialen NV, Arnhem (Netherlands)); Waal, H. de (TPD-TNO-Glass technology, Eindhoven (Netherlands))

    1989-09-26

    Diffusion of cesium in borosilicate glass for high-level radioactive waste is discussed. For this purpose model glasses with non-radioactive elements are being made, in accordance with the specifications of the reprocessing plants, from which concentration couples are composed. A concentration couple consists of two cylinders of borosilicate glass which contain different amounts of cesium. After heat treatment the couples are studied by means of the scanning electron microscopy and X-ray microanalysis. The model study will provide a basis for predictions of the containment achieved over a longer period of time. (author). 11 refs.; 2 figs.; 2 tabs.

  1. 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.

  2. A sulphated flavone glycoside from Livistona australis and its antioxidant and cytotoxic activity.

    Science.gov (United States)

    Kassem, Mona E S; Shoela, Soha; Marzouk, Mona M; Sleem, Amany A

    2012-01-01

    A new flavone glycoside tricin 7-O-β-glucopyranoside-2″-sulphate sodium salt along with 14 known flavonoid compounds were isolated and identified from the aqueous methanol extract of Livistona australis leaves. Their structures were established on the basis of extensive NMR (¹H, ¹³C, HSQC and H-H COSY) and ESIMS data. Antioxidant and cytotoxicity properties of the methanol extract of the leaves as well as the new compound were investigated.

  3. Bronchography in dogs. Comparative study with two barium sulphate solutions

    International Nuclear Information System (INIS)

    Thibaut, J.; Gallardo, P.; Vargas, L.; Deppe, R.; Born, R.

    1998-01-01

    Two solutions of barium sulphate, 60 and 30% w/v, were compared with the ''overflow'' Bronchographic method. Two groups of eight healthy adult does of both sexes, weighing 7 to 18 kg were used for the study. The dogs were anaesthetised with thiopentone sodium 2% (20 mg/kg iv). After intubation, each dog received contrast medium by a catheter connected to a syringe, in a 9 mi dose. Two series of two x-rays plates were taken in left lateral recumbent, 3 and 6 min after administering the contrast medium and in ventrodorsal projection, 30 sec. later. The x-ray plates obtained were analysed and compared intra and inter group considering the advance speed of the contrast medium, the radiographic density and outlines. Adverse reactions were controlled

  4. Small angle neutron scattering studies of mixed micelles of sodium

    Indian Academy of Sciences (India)

    The aqueous solutions of sodium cumene sulphonate (NaCS) and its mixtures with each of cetyl trimethylammonium bromide (CTAB) and sodium dodecyl sulphate (SDS) are characterized by small angle neutron scattering (SANS). NaCS when added to CTAB solution leads to the formation of long rod-shaped micelles with ...

  5. Influence of puerperium on the serum proteins of Saanen goats, obtained by the analysis of electrophoresis on sodium dodecyl sulphate-polyacrylamide gel / Influência do puerpério sobre o proteinograma sérico de caprinos da raça Saanen obtido por eletroforese em gel de poliacrilamida

    Directory of Open Access Journals (Sweden)

    Eduardo Harry Birgel Junior

    2009-10-01

    Full Text Available Aiming to evaluate the puerperal influence on the proteinogram of Saanen goats, 108 samples of blood serum from 12 goats were collected, and the results were presented at nine times: just after parturition, 1, 3, 5, 7, 10, 15, 21 and 30 days after parturition. Total amount of serum proteins were determined by the biuret technique, and the sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE was used to the protein fractionation. In this last method, 17 protein bands were observed, from which molecular weights varied between 25 KDa and 275 KDa. In addition, it was possible to identify the following protein fractions: immunoglobulin A (180 KDa, ceruloplasmin (115 KDa, transferrin (79 KDa, albumin (65 KDa, heavy-chain immunoglobulin G (58 KDa, haptoglobin (45 KDa, acid glycoprotein (37 KDa and light-chain immunoglobulin G (28 KDa. Another 9 nonidentified protein fractions presented, each molecular weights equal to 275 KDa, 140 KDa, 125 KDa, 103 KDa, 95 KDa, 41 KDa, 35 KDa, 30 Kda and 25 KDa. The results allow us to conclude that by the first week of puerperium, an improvement of acid glycoprotein occurs, whereas those others protein fractions do not suffer any puerperal influence.Com o objetivo de avaliar a influência do puerpério no proteinograma de caprinos da raça Saanen foram colhidas 108 amostras de soro sangüíneo de 12 cabras, sendo os resultados apresentados em nove momentos: imediatamente após a parição, 1, 3, 5, 7, 10, 15, 21 e 30 dias após o parto. Os teores séricos de proteína total foram determinados pela técnica do biureto, e para o fracionamento das proteínas foi realizada a eletroforese em gel de poliacrilamida contendo dodecil sulfato de sódio (SDS-PAGE. No método utilizado foram observadas 17 bandas protéicas, cujos pesos moleculares (PM variaram de 25 KDa a 275 KDa, sendo possível a identificação das seguintes frações protéicas: imunoglobulina A (180 KDa, ceruloplasmina (115 KDa, transferrina

  6. Optical properties of highly Er{sup 3+}-doped sodium-aluminium-phosphate glasses for broadband 1.5 {mu}m emission

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A. Amarnath [Nanophotonics Laboratory, Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India); Babu, S. Surendra [Laser Instrumentation Design Centre, Instrument Research and Development Establishment, Dehradun 248008 (India); Pradeesh, K. [Nanophotonics Laboratory, Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India); Otton, C.J. [Valencia Nanophotonics Technology Center, Universidad Politecnica de Valencia, 46022 Valencia (Spain); Vijaya Prakash, G., E-mail: prakash@physics.iitd.ac.in [Nanophotonics Laboratory, Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India)

    2011-03-03

    Research highlights: > Highly Er{sup 3+} doped phosphate glasses for the 1.54 {mu}m laser emission were explored. > Emission from these doped glasses shows larger lifetimes and quantum efficiencies. > Optical amplifier parameters are greater than other reported phosphate glasses. > The durability and obtained results are most favourable for short-length amplifiers. - Abstract: Erbium-doped Na{sub 3}Al{sub 2}P{sub 3}O{sub 12} (NAP) glasses with compositions 92NAP-(8-x)Al{sub 2}O{sub 3}-(x)Er{sub 2}O{sub 3} (where x = 2-8) were prepared and characterized for absorption, visible and NIR emission and decay time properties. Judd-Ofelt analysis has been carried out to predict radiative properties of luminescent levels of Er{sup 3+} ions. Comparatively larger photoluminescence lifetimes (7.86 ms) and larger quantum efficiencies (74%) for the laser transition, {sup 4}I{sub 13/2} {yields} {sup 4}I{sub 15/2} (at 1.54 {mu}m) are observed. The moisture insensitivity, large Er{sup 3+} ion doping capability and relatively high-gain and broad emission at 1.5 {mu}m are the most notable features of these glasses to realize efficient short-length optical amplifiers.

  7. The Reclamation of Industrial Wastes Inclusive Sulphates by Sulphate-Reducing Bacteria

    Directory of Open Access Journals (Sweden)

    Mária Kušnierová

    2004-12-01

    Full Text Available The objective of our study was to verify experimentally the possibility of using coal mine drainage and gypsum from the „stabilizate“ (the final product from the combustion desulphurisation as the source of sulphate for the cultivation of SRB with the prospect of: purging of mine waste waters inclusive sulphates, recycling of desulphurisation agent (limestone and production of elemental sulphur from hydrogen sulphide. The results confirmed the theoretical assumptions on the use of gypsum, which forms the substantial component of „stabilizate“, as the source of sulphate for sulphate-reducing bacteria, which produce hydrogen sulphide in the process of bacterial reduction of sulphates. They also showed the possibility of recycling the desulphurisation agent – limestone, as well as the realistic alternative of using „stabilizate“ in the production of elemental sulphur which still represents an important raw material needed in chemical, paper or other industries.

  8. Post traumatic tetanus and role magnesium sulphate

    International Nuclear Information System (INIS)

    Sikendr, R.I.; Samad, B.U.; Memon, M.I.

    2009-01-01

    Tetanus is a life threatening disease. Reported mortality for tetanus is 15-39%. Conventional treatment includes heavy sedation and artificial ventilation. Complications resulting from long term heavy sedation and artificial ventilation contribute to 60% of the total mortality caused by tetanus. In this study magnesium sulphate was used to reduce the need for sedation and artificial ventilation. Objectives of this prospective study were to determine the role of magnesium sulphate in post traumatic tetanus. The study was carried out in surgical Intensive Care at Pakistan Institute of Medical Sciences (PIMS), Islamabad from Jan 2004 to Dec 2007. Forty-four patients presented during this period and 33 patients were included in the study. All patients had tracheostomy done within 48 hours. Every patient was started Magnesium Sulphate therapy for control of spasms after sending baseline investigations. Patients were given ventilatory support when needed. All data was entered in well structured proforma. SPSS-10 was used to analyse data. Thirty-three patients were included in the study and all patients were given magnesium sulphate. Out of these, 45.5% cases were grade 4 tetanus, 73.6% and 63.3% cases did not require artificial ventilation and additional sedation respectively, 51.1% patients remained free of complications of tetanus. Overall mortality was 30.3%. Use of Magnesium Sulphate is safe and reduces the need for sedation and artificial ventilation in high grade tetanus thus contributing to survival benefit in adult post-traumatic tetanus cases. (author)

  9. Removal of radium from aqueous sulphate solutions

    International Nuclear Information System (INIS)

    Weir, D.R.; Masters, J.T.; Neven, M.

    1983-01-01

    Radium is often present in ores and an aqueous solution associated with the ore may consequently contain dissolved radium. It is frequently necessary to remove radium from such solutions to reduce the total radium content to a prescribed low level before the solution can be returned to the environment. The present invention is based on the discovery that the total radium content can be reduced to a satisfactory level within a reasonable time by adding a soluble barium salt to a radium-containing sulphate solution which also contains dissolved magnesium at a pH not greater than about 0 to precipitate radium as barium radium sulphate, raising the pH to at least 11 to precipitate an insoluble magnesium compound which collects the barium radium sulphate precipitate, and separating substantially all of the precipitates from the solution

  10. Spectroscopic investigations of OH{sup -} influence on near-infrared fluorescence quenching of Yb{sup 3+}/Tm{sup 3+} co-doped sodium-metaphosphate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Terra, I.A.A. [Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, Av. Trabalhador Saocarlense 400, CEP 13566-590, USP-Sao Carlos, SP (Brazil)], E-mail: idelma@ifsc.usp.br; Camargo, A.S.S. de; Terrile, M.C.; Nunes, L.A.O. [Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, Av. Trabalhador Saocarlense 400, CEP 13566-590, USP-Sao Carlos, SP (Brazil)

    2008-05-15

    Energy transfer processes were studied in two sets of Yb{sup 3+} and Tm{sup 3+} co-doped sodium-metaphosphate glasses, prepared in air and nitrogen atmospheres. Using Foerster, Dexter, and Miyakawa theoretical models, the energy transfer parameters were calculated. The main ion-ion energy transfer processes analyzed were energy migration among Yb{sup 3+} ions, cross-relaxations between Yb{sup 3+} and Tm{sup 3+} ions, and interactions with OH{sup -} radicals. The results indicated that Yb{yields}Tm energy transfer favors 1.8 {mu}m emissions, and there is no evidence of concentration quenching up to 2% Tm{sub 2}O{sub 3} doping. As expected, samples prepared in nitrogen atmosphere present higher fluorescence quantum efficiency than those prepared in air, and this feature is specially noted in the near-infrared region, where the interaction with the OH{sup -} radicals is more pronounced.

  11. Thermal decomposition of uranyl sulphate hydrate

    International Nuclear Information System (INIS)

    Sato, T.; Ozawa, F.; Ikoma, S.

    1980-01-01

    The thermal decomposition of uranyl sulphate hydrate (UO 2 SO 4 .3H 2 O) has been investigated by thermogravimetry, differential thermal analysis, X-ray diffraction and infrared spectrophotometry. As a result, it is concluded that uranyl sulphate hydrate decomposes thermally: UO 2 SO 4 .3H 2 O → UO 2 SO 4 .xH 2 O(2.5 = 2 SO 4 . 2H 2 O → UO 2 SO 4 .H 2 O → UO 2 SO 4 → α-UO 2 SO 4 → β-UO 2 SO 4 → U 3 O 8 . (author)

  12. An electrochemical study of the effect of nitrate and sulphate on the corrosion behaviour of Magnox AL80 in pond environments

    International Nuclear Information System (INIS)

    Tyfield, S.P.; Martin, F.

    1987-04-01

    The open circuit rest potential and the cyclic potentiodynamic polarisation behaviour of abraded Magnox AL80 has been studied at 22 0 C in sodium hydroxide solutions (200 gm -3 , pH ∼ 11.6) dosed separately and with a combination of chloride and nitrate. The results are considered in terms of the effect of the presence of nitrate on the initiation of localised breakdown of the passive film on Magnox AL80. A similar study of the effect of the presence of sulphate in the sodium hydroxide medium (200 gm -3 ) is described and the aggressivity of sulphate is compared to that of chloride. (author)

  13. Computerised analysis of sulphate action on model concrete piles

    Digital Repository Service at National Institute of Oceanography (India)

    Deshmukh, A.M.; Balasubramanian, S.; Venugopal, C.

    Sulphate action severely affects the durability of marine structures. It is imperative to study precisely the effects of magnesium sulphate on pile foundations in the marine environment. In the present paper an attempt is made to assess and analyse...

  14. Test plan for glass melter system technologies for vitrification of hign-sodium content low-level radioactive liquid waste, Project No. RDD-43288

    International Nuclear Information System (INIS)

    Higley, B.A.

    1995-01-01

    This document provides a test plan for the conduct of combustion fired cyclone vitrification testing by a vendor in support of the Hanford Tank Waste Remediation System, Low-Level Waste Vitrification Program. The vendor providing this test plan and conducting the work detailed within it is the Babcock ampersand Wilcox Company Alliance Research Center in Alliance, Ohio. This vendor is one of seven selected for glass melter testing

  15. Synthesis of specifically deuterated pregnanolone and pregnanediol sulphates for metabolic studies in pregant women

    International Nuclear Information System (INIS)

    Baillie, T.A.; Herz, J.E.; Anderson, R.A.; Sjovall, J.

    1975-01-01

    A series of specifically deuterated isomers of pregnanolone sulphate and pregnanediol mono- and disulphate have been synthesized for use in a study of the formation and metabolism of C 21 -steroid sulphates in the plasma of pregnant women. Hecogenin, the starting material for the synthesis, was equilibrated with NaO 2 H- 2 H 2 O and the resulting 11,11- 2 H 2 derivative converted directly to its tosylhydrazone. Reduction with sodium borohydride and degradation of the sapogenin side-chain gave 3β-hydroxy-5α-[11,11- 2 H 2 ] pregn-16-en-20-one (isotopic purity 91.6%). Further deuterium atoms were introduced in the 3α and 3α,20β positions by reductions with sodium borodeuteride and lithium aluminum deuteride, respectively. These reactions led to 3β-hydroxy-5α-[3α,11,11- 2 H 3 ] pregnan-20-one (isotopic purity 87.2%) and 5α-[3α,11,11,20β- 2 H 4 ] pregnane-3β,20α-diol (isotopic purity 83.9%). Steroids possessing the less readily accessible 3α-hydroxy-5α-[3β- 2 H] configuration were obtained, without loss of label, by epimerization of the 3β isomers. Pregnanolone sulphates and pregnanediol disulphates were prepared directly from the free alcohols, while the pregnanediol 3-monosulphates were synthesized from the appropriate pregnanediol 20-monoacetate derivatives

  16. Controlling Barium Sulphate Scale Deposition Problems in an unbleached Kraft Paper Mill

    CSIR Research Space (South Africa)

    Sithole, Bruce

    2015-06-01

    Full Text Available Troubleshooting of scale deposits and defects in paper samples showed that the problem was caused by barium sulphate and calcium sulphate scales. However, it was ascertained that barium sulphate was more of a concern than calcium sulphate...

  17. Formulation and evaluation and terbutaline sulphate and ...

    African Journals Online (AJOL)

    We report the use of low rugosity lactose, product of controlled crystallization of this carrier, in the formulation of terbutaline sulphate and beclomethasone dipropionate dry powder inhalers. The deposition patterns obtained with inhalation mixtures consisting of the modified lactose and each of the micronised drugs ...

  18. Removal of Sulphate and Manganese on Synthetic Wastewater in Sulphate Reducing Bioreactor Using Indonesian Natural Zeolite

    Directory of Open Access Journals (Sweden)

    Endah Retnaningrum

    2017-07-01

    Full Text Available The present research was conducted to investigate sulphate and manganese removal from synthetic wastewater. The continuous laboratory scale of down-flow fluidized-bed reactor (DFBR using sulphate reducing bacteria (SRB consortium and Indonesian natural zeolite as a bacterial support material was designed. At 9 days operation, maximum sulphate and manganese removal was observed to be 23% and 15.4%, respectively. The pH values were also changed to neutral. The population of SRB increased which effect on the raising of their activity for removing sulphate and manganese. Using the scanning electronic microscopy (SEM, it was observed that natural zeolite possesses excellent physical characteristics as a bacterial support material in DFBR. The imaging SEM result of SRB consortium on zeolite surface clearly showed the developed SRB biofilm on that particle. Analysis result of EDX confirmed that manganese was precipitated as manganese–sulfides.

  19. Mortar and concrete based on calcium sulphate binders

    NARCIS (Netherlands)

    Bakker, J.J.F.; Brouwers, H.J.H.; Fischer, H.B

    2006-01-01

    In this study both hemi-hydrate and anhydrite are tested as calcium sulphate binders for structural mortar and concrete. The advantage of using calcium sulphates instead of cement as a binder is the fact that the production of calcium sulphate is more environmental friendly than that of cement. For

  20. Chromium content in human skin after in vitro application of ordinary cement and ferrous-sulphate-reduced cement

    DEFF Research Database (Denmark)

    Fullerton, A; Gammelgaard, Bente; Avnstorp, C

    1993-01-01

    The amount of chromium found in human skin after in vitro application of cement suspensions on full-thickness human skin in diffusion cells was investigated. Cement suspensions made from ordinary Portland cement or Portland cement with the chromate reduced with added ferrous sulphate were used....... The cement suspensions were either applied on the skin surface under occlusion for 48 h or applied repeatedly every 24 h for 96 h. No statistically significant difference in chromium content of skin layers between skin exposed to ordinary Portland cement, skin exposed to cement with added ferrous sulphate...... and unexposed skin was observed, despite a more permeable skin barrier at the alkaline pH of the cement suspensions, i.e., pH 12.5. Increased chromium levels in epidermis and dermis were seen when ordinary Portland cement was applied as a suspension with added sodium sulphate (20%) on the skin surface for 96 h...

  1. Sodium distiller II

    International Nuclear Information System (INIS)

    Goncalves, A.C.; Castro, P.M. e; Torres, A.R.; Correa, S.M.

    1990-01-01

    A sodium distiller allows the evaluation of the sodium purity, contained in plants and circuits of Fast Reactors. The sodium distillers of the IEN Reactor's Department was developed initially as a prototype, for the testing of the distillation process and in a second step, as a equipment dedicated to attendance the operation of these circuits. This last one was build in stainless steel, with external heat, rotating crucible of nickel for four samples, purge system for pipe cleaning and a sight glass that permits the observation of the distillation during all the operation. The major advantage of this equipment is the short time to do a distillation operation, which permits its routine utilization. As a consequence of the development of the distillers and its auxiliary systems an important amount of new information was gathered concerning components and systems behaviour under high temperature, vacuum and sodium. (author)

  2. Reuse of partially sulphated CFBC ash as an SO{sub 2} sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Y.; Jia, L.; Anthony, E.J. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Energy; Nobili, M.; Telesca, A. [Basilicata Univ., Potenza (Italy). Dept. of Environmental Engineering and Physics; Montagnaro, F. [Naples Univ., Naples (Italy). Dept. of Chemistry

    2010-06-15

    Ash produced from circulating fluidized bed combustion (CFBC) boilers typically contains large amounts of unreacted calcium oxide (CaO) when limestone is added into the combustor for in situ removal of sulphur dioxide (SO{sub 2}). This paper reported on a study that evaluated the reactivation of partially sulphated ash obtained from an industrial circulating fluidized bed combustion (CFBC) boiler by hydration with liquid water and steam. A pilot-scale mini-CFBC was used to evaluate the results of reactivation on the bed ash by hydrating with liquid water and admixtures of sodium carbonate (Na{sub 2}CO{sub 3}) in solution or as powder. Re-sulphation tests on the hydrated samples were performed in a Cahn 1000 thermogravimetric analyzer (TGA) at 850 degrees C for 90 minutes in a simulated flue gas environment with sulphur dioxide (SO{sub 2}) concentration at 5000 ppm. Re-sulphation was carried out on unhydrated ash at the same conditions used in the baseline test. The TGA results showed that although liquid water and steam successfully hydrate and reactivate the unreacted CaO in the bed ash, the treated ashes sulphated to widely different extents. Attempts to reactivate fly ash with hydration failed, but the fly ash by itself was extremely reactive. When the treated ash was re-injected into the combustor with the fuel, the effect on SO{sub 2} removal efficiency was negligible if Na{sub 2}CO{sub 3} was added as powder. Doping with aqueous solution improved SO{sub 2} removal, but to a lesser extent than if only water hydration was used. Increasing the amount of water to reactivate the ash did not improve the sulphur capture capacity in the mini-CFBC. It was concluded that reactivation by water is the most practical way to reuse the partially sulphated bed ash as a sulphur sorbent. 21 refs., 7 tabs., 3 figs.

  3. Effect of co-doping of sodium on the thermoluminescence dosimetry properties of copper-doped zinc lithium borate glass system

    International Nuclear Information System (INIS)

    Saidu, A.; Wagiran, H.; Saeed, M.A.; Alajerami, Y.S.M.; Kadir, A.B.A.

    2016-01-01

    The effect of sodium as a co-dopant on the thermoluminescence (TL) properties of copper-doped zinc lithium borate (ZLB: Cu) subjected to Co-60 gamma radiation is reported in this study. TL intensity is enhanced with the introduction of sodium in ZLB: Cu. The obtained glow curve is simple with a single peak. The annealing procedure and the best heating rate for the proposed thermoluminescent dosimeter (TLD) are established, and the phosphor is reusable. The TL response within the dose range of 0.5–1000 Gy is investigated. The results show that the thermal fading behaviour is improved significantly. - Highlights: • Dosimetry properties of an improved TL dosimeter. • The dosimeter is made of lithium borate, modified with ZnO, doped with CuO and co-doped with Na 2 O. • With addition of Na to Cu in the ZLB host, TL yield and sensitivity has significantly enhanced. • The fading behaviour has also been minimized significantly. • The new material is also characterized with the linear dose response, and good reproducibility behaviour.

  4. Energy transfer processes in Yb{sup 3+}-Tm{sup 3+} co-doped sodium alumino-phosphate glasses with improved 1.8 {mu}m emission

    Energy Technology Data Exchange (ETDEWEB)

    Camargo, Andrea S S de; Terra, Idelma A A; Nunes, Luiz Antonio de O; Li, M Siu [Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, 13560-970, Sao Carlos-SP (Brazil)], E-mail: andreasc@ifsc.usp.br

    2008-06-25

    Sodium alumino-phosphate glasses co-doped with Yb{sup 3+} and Tm{sup 3+} ions have been prepared with notably low OH{sup -} content, and characterized from the viewpoint of their spectroscopic properties. In these glasses, Yb{sup 3+} acts as an efficient sensitizer of excitation energy at 0.98 {mu}m-which can be provided by high power and low cost diode lasers, and subsequently undergoes non-resonant energy transfer to Tm{sup 3+} ions ({sup 2}F{sub 5/2}, {sup 3}H{sub 6} {yields} {sup 2}F{sub 7/2}, {sup 3}H{sub 5}). Through this process, the emitting level {sup 3}F{sub 4} is rapidly populated, generating improved emission at 1.8 {mu}m ({sup 3}F{sub 4} {yields} {sup 3}H{sub 6}). In order to guarantee the efficiency of such favorable energy transfer, energy losses via multiphonon decay, Yb-Yb radiative trapping, and non-radiative transfer to OH{sup -} groups were evaluated, and minimized when possible. The dipole-dipole energy transfer microscopic parameters corresponding to Yb{sup 3+} {yields} Tm{sup 3+}, Yb{sup 3+} {yields} Yb{sup 3+} and Tm{sup 3+} {yields} Tm{sup 3+} transfers, calculated by the Foerster-Dexter model, are C{sub Yb-Tm} = 2.9 x 10{sup -40} cm{sup 6} s{sup -1}, C{sub Yb-Yb} = 42 x 10{sup -40} cm{sup 6} s{sup -1} and C{sub Tm-Tm} = 43 x 10{sup -40} cm{sup 6} s{sup -1}, respectively.

  5. Electroactive biofilms of sulphate reducing bacteria

    International Nuclear Information System (INIS)

    Cordas, Cristina M.; Guerra, L. Tiago; Xavier, Catarina; Moura, Jose J.G.

    2008-01-01

    Biofilms formed from a pure strain of Desulfovibrio desulfuricans 27774 on stainless steel and graphite polarised surfaces were studied. The polarisation conditions applied were -0.4 V vs. SCE for different times. A cathodic current related with the biofilms growth was observed with a maximum intensity of -270 mA m -2 that remained stable for several days using graphite electrodes. These sulphate reducing bacteria biofilms present electrocatalytic activity towards hydrogen and oxygen reduction reactions. Electrode polarisation has a selective effect on the catalytic activity. The biofilms were also observed by scanning electronic microscopy revealing the formation of homogeneous films on the surfaces

  6. Constant current chronopotentiometric stripping of sulphated polysaccharides

    Czech Academy of Sciences Publication Activity Database

    Strmečki, S.; Plavšić, M.; Ćosović, B.; Ostatná, Veronika; Paleček, Emil

    2009-01-01

    Roč. 11, č. 10 (2009), s. 2032-2035 ISSN 1388-2481 R&D Projects: GA ČR(CZ) GA301/07/0490; GA ČR(CZ) GP202/07/P497; GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : sulphated polysaccharides * ióta-carrageenan * catalysis of hydrogen evolution Subject RIV: BO - Biophysics Impact factor: 4.243, year: 2009

  7. Electroactive biofilms of sulphate reducing bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Cordas, Cristina M.; Guerra, L. Tiago; Xavier, Catarina [Requimte-CQFB, Departamento de Quimica, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Moura, Jose J.G. [Requimte-CQFB, Departamento de Quimica, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)], E-mail: jose.moura@dq.fct.unl.pt

    2008-12-01

    Biofilms formed from a pure strain of Desulfovibrio desulfuricans 27774 on stainless steel and graphite polarised surfaces were studied. The polarisation conditions applied were -0.4 V vs. SCE for different times. A cathodic current related with the biofilms growth was observed with a maximum intensity of -270 mA m{sup -2} that remained stable for several days using graphite electrodes. These sulphate reducing bacteria biofilms present electrocatalytic activity towards hydrogen and oxygen reduction reactions. Electrode polarisation has a selective effect on the catalytic activity. The biofilms were also observed by scanning electronic microscopy revealing the formation of homogeneous films on the surfaces.

  8. Determination of chloride and sulphur in sodium by ion chromatography and its application to PFBR sodium samples

    International Nuclear Information System (INIS)

    Vijayalakshmi, S.; Ushalakshmi, K.

    2011-01-01

    Analytical method using ion chromatography was developed for the determination of chloride and sulphur in sodium. In this method, sodium was dissolved in water and various sulphur species present in the sample was oxidized to sulphate using hydrogen peroxide. Carbon dioxide gas was passed through the solution to convert sodium hydroxide to carbonate solution. The resulting sample solution was analysed using suppressed Ion chromatography employing carbonate eluent. This method was applied to the analysis of sodium samples procured for prototype fast breeder reactor. (author)

  9. Glass sealing

    Energy Technology Data Exchange (ETDEWEB)

    Brow, R.K.; Kovacic, L.; Chambers, R.S. [Sandia National Labs., Albuquerque, NM (United States)

    1996-04-01

    Hernetic glass sealing technologies developed for weapons component applications can be utilized for the design and manufacture of fuel cells. Design and processing of of a seal are optimized through an integrated approach based on glass composition research, finite element analysis, and sealing process definition. Glass sealing procedures are selected to accommodate the limits imposed by glass composition and predicted calculations.

  10. Effectivness of dexametasone vs. Magnesium sulphate in postoperative analgesia: Dexametasone vs. Magnesium sulphate

    Directory of Open Access Journals (Sweden)

    Dautaj Brikena

    2016-01-01

    Full Text Available Introduction: Preoperative use of additive substances may be very helpful in perioperative acute pain management. Intravenous administration of dexametasone in preoperative period prevents postoperative nausea and vomiting but also provides better pain relief. It is also well known that magnesium sulphate (the NMDA receptor's antagonist by its central mechanism of action may be effective in postoperative pain control. Aim: The purpose of this study was to evaluate the effect of dexametasone and magnesium sulphate on postoperative pain management in patients undergoing abdominal surgery (open cholecystectomy. Methods: Seventy eight patients scheduled for elective surgery (open cholecystectomy were included in this study. This was the prospective cohort randomized placebo- controlled study. A total of 78 patients were randomized into three groups. Each group had twenty six patients. The group D, received dexametasone 0.1 mg/ kg iv 30 minutes before surgery. The group M received magnesium sulphate 3 mg/kg iv 30 minutes before surgery. The third group S was placebo group and patients in this group received saline in the same volume for each patient. For pain control after surgery all patients received tramadol 0.9-1.2 mg/kg and diklophenac 1.76 mg/kg. When necessary (VAS ≥ 7, morphine sulphate in dose 0.15 mg/kg was administred subcutaneously For treatment of emetic episodes metoclopramid 10 mg iv. was used. The patients were observed for intensity of pain measured VAS 0-10, pain relief and satisfaction with therapy, sedation, adverse events, emetic episodes and hemodynamic parameters. Results: There was no difference between groups regarding demographic data (age, gender, body weight, ASA score, comorbidity, duration of surgery and anesthesia and amount of fentanyl received during surgery. In group D 11.54% of patients received additional analgesia (morphine sulphate 0.15 mg/kg sc in the first 4 hours and 27% of patients in the first 24 hours

  11. Calibration of brachytherapy sources using ferrous sulphate-benzoic acid-xylenol orange dosimeter

    International Nuclear Information System (INIS)

    Madhvanath, U.; Kini, U.R.; Gupta, B.L.

    1976-01-01

    A solution containing 0.20 mM of ferrous ammonium sulphate, 5.0 mM benzoic acid and 0.20 mM xylenol orange in 0.05 N sulphuric acid was used for the calibration of 252 Cf, 137 Cs, 226 Ra and 60 Co needle sources. A known volume of this solution contained in a pyrex glass tube was irradiated with the source kept in a glass capillary at the centre of the solution. A few hours of irradiation were required for each needle and the absorbance of the solution was measured at 540 nm against the unirradiated solution. The accuracy of this method was found to be within a few percent and is particularly useful for 252 Cf sources as the neutron component of the source contributes significantly to the absorbance produced. (author)

  12. Electrochromic Glasses.

    Science.gov (United States)

    1980-07-31

    this glass and that dipole-dipole correlations contribute to the "ferroelectric-like" character of this amorphous system. The TeO2 -W03 glasses can only...shows the dielectric constant and Fig. I(b) glass from pure TeO2 ot pure WO. In addition, glass the tan 8 of the WO glass as a function of temperature... glasses containing WO, in various glass forming nitworks of LifO-B1O0, Na:O-BzO,, and TeO2 were prepared from reagent grade oxides at 800 C - 9SO C in

  13. Reuse of Partially Sulphated CFBC Ash as an SO2 Sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yinghai; Jia, Lufei; Anthony, E.J. [CanmetENERGY, 1 Haanel Drive, Ottawa, Ontario, K1A1M1 (Canada); Nobili, M.; Telesca, A. [Department of Environmental Engineering and Physics, University of Basilicata, Viale dell' Ateneo, Lucano 10, 85100 Potenza (Italy); Montagnaro, F. [Department of Chemistry, University of Naples ' Federico II' , Monte Sant' Angelo, 80126 Naples (Italy)

    2010-06-15

    Ashes produced from fluidized bed combustors (FBC) burning high-sulphur fuels often contain 20-30 % unreacted CaO because of the limestone added to remove SO2 in situ. This paper presents the results from experiments into reactivating partially sulphated FBC ash (both bed ash and fly ash) with liquid water, steam and sodium carbonate. The water- or steam-hydrated ashes were subsequently re-sulphated in a thermogravimetric analyzer (TGA) with simulated flue gas. The TGA results show that, while liquid water and steam successfully hydrate and reactivate the unreacted CaO in the bed ash, the treated ashes sulphated to widely different extents. Attempts to reactivate fly ash with hydration failed, although fly ash by itself is extremely reactive. A pilot-scale mini-circulating FBC (CFBC) was also used to evaluate the results of reactivation on the bed ash by hydrating with liquid water and admixtures of inorganic salt (Na2CO3) in the form of either powder or solution. When the treated ash was re-injected into the combustor with the fuel, the effect on SO2 removal efficiency was negligible if Na2CO3 was added as powder. Doping with aqueous solution resulted in enhanced SO2 removal; however, the extent was lower than the level achieved if only water hydration was employed. Increasing the amount of water (from 10% to 30%) to reactivate the ash did not improve the sulphur capture capacity in the mini-CFBC. Overall, this study suggests that the most practical way for re-use of the partially sulphated bed ash as a sulphur sorbent is reactivation by water. A proposal for utilization of the fly ash in an economically reasonable way is also discussed.

  14. Accelerating the transit time of barium sulphate suspensions in small bowel examinations

    International Nuclear Information System (INIS)

    Summers, David S.; Roger, Mark D.; Allan, Paul L.; Murchison, John T.

    2007-01-01

    Purpose: To determine whether hyperosmolar and effervescent agents proven individually to accelerate transit time in the barium small bowel examination have an additive effect when combined, surpassing that of either agent alone. Materials and methods: One hundred and forty-nine patients were randomised to four groups. Three hundred milliliters of barium sulphate alone was given to the first group. Fifteen milliliters of iodinated hyperosmolar contrast agent (Gastrografin, meglumine/sodium diatrizoate, Schering) was given in addition to barium sulphate to the second group while six packets of effervescent granules (Carbex, Ferring) were added for the third group. The final group was given a combination of both additives and barium sulphate. The time taken following ingestion for the contrast column to reach the caecum, as assessed by frequent interval fluoroscopy, was recorded. A subgroup of 32 patients were selected randomly from the four groups, 8 from each and assessed for quality of examination. Statistical assessments were made using Kruskal-Wallis and Mann-Whitney tests. Results: One hundred and nineteen patients were analysed after exclusions. The addition of accelerant to barium sulphate, both individually and in combination significantly reduced the small bowel transit time (p < 0.001). No significant difference existed between the additives when used with barium alone. The combined group had significantly faster transit times compared to the hyperosmolar group (p = 0.02). Differences between combined and effervescent groups tended towards significance (p = 0.09). No significant difference existed between groups when examination quality was assessed. Conclusion: These results suggest that the addition of combined effervescent and hyperosmolar agents to the barium suspension may significantly shorten the small bowel transit time without adversely affecting examination quality. This has implications for patient acceptability of the examination as well as

  15. Microstructural characterization and electrochemical corrosion behavior of Incoloy 800 in sulphate and chloride solutions

    International Nuclear Information System (INIS)

    Mansur, Fabio Abud; Schvartzman, Monica Maria de Abreu Mendonca; Campos, Wagner Reis da Costa; Aguiar, Antonio Eugenio de; Chaim, Marcos Souza

    2011-01-01

    Corrosion has been the major cause of tube failures in steam generators (SG) tubes in nuclear power plants. Problems have resulted from impurities in the secondary water systems which are originated from leaks of cooling water. It is important to understand the compatibility of steam generator tube materials with the environment. This study presents the microstructural characterization and electrochemical behavior of the Incoloy 800 in sodium chloride and sodium sulphate aqueous solutions at 80 degree C. Potentiodynamic anodic polarization, cyclic polarization and open circuit potential (OCP) measurements were the electrochemical techniques applied in this work. The pitting resistance of Incoloy 800 in chloride plus sulphate mixtures were also examined. Experiments performed in solutions with different concentrations of Cl- and SO 4 2- ions in solution (200 ppb, 500 ppb, 1ppm, 5 ppm, 50 ppm and 100 ppm) showed that this concentrations range had no substantial effect on the anodic behavior of the alloy. After polarization no localized corrosion was found on the samples. (author)

  16. Citrate increases glass transition temperature of vitrified sucrose preparations

    NARCIS (Netherlands)

    Kets, E.P.W.; Lipelaar, P.J.; Hoekstra, F.A.; Vromans, H.

    2004-01-01

    The aim of this study was to investigate the effect of sodium citrate on the properties of dried amorphous sucrose glasses. Addition of sodium citrate to a sucrose solution followed by freeze-drying or convective drying resulted in a glass transition temperature (T-g) that was higher than the

  17. Differential responses of freshwater wetland soils to sulphate pollution

    NARCIS (Netherlands)

    Lamers, L.P.M.; Dolle, ten G.E.; Berg, van den S.T.G.; Delft, van S.P.J.; Roelofs, J.G.M.

    2001-01-01

    Sulphate (SO42-) reduction rates are generally low in freshwater wetlands and are regulated by the scarce availability of the ion. Increased concentrations of this electron acceptor due to sulphur (S) pollution of groundwater and surface water may, however, lead to high sulphate reduction rates now

  18. Safety and efficacy of Bolus administration of magnesium sulphate ...

    African Journals Online (AJOL)

    Safety and efficacy of Bolus administration of magnesium sulphate for preeclampsia. ... On-going research is addressing its administration in terms of dosage, duration and safety. Objective: We evaluated a ... Keywords: safety, efficacy, bolus magnesium sulphate, preeclampsia, University of Benin Teaching Hospital

  19. Kinetics and mechanism of protection of thymine from sulphate ...

    Indian Academy of Sciences (India)

    Unknown

    The rate constant of sulphate radical anion with caffeic acid has been ... transfer of radical sites from base moiety to sugar moiety. Strand ... titrated with a standard ceric ammonium sulphate solution as reported by Kapoor et al.7. At room ...

  20. The ions displacement through glasses

    International Nuclear Information System (INIS)

    Sevegnani, F.X.

    1980-01-01

    A method to introduce sodium, potassium, lithium, calcium, iron and other ions in vacuum or gas light bulb by mean of a strong stationay electric field. The experiments showed that the mass deposited inside the bulbs obey Faraday's law of electrolysis, although the process of mass transfer is not that of a conventional electrolysis. A method which allows to show that hydrogen ions do not penetrate the glass structure is also described. Using radioactive tracers, it is shown that heavy ions, such PO 4 --- do not penetrate the glass structure. The vitreous state and the glass properties were studied for interpreting experimental results. (Author) [pt

  1. Sulphate rocks as an arena for karst development

    Directory of Open Access Journals (Sweden)

    Andrejchuk V.

    1996-01-01

    Full Text Available The rocks in which karst systems develop are most commonly composed of carbonate sulphate and chloride minerals. The sulphate minerals are quite numerous, but only gypsum and anhydrite form extensive masses in sedimentary sequences. Other minerals, which represent sulphates of K, Mg and Na, normally occur as minor beds (0.1-5.0 m, or as inclusions associated with chloride rocks. However some minerals precipitated in salt-generating basins, such as mirabilite and glauberite (typically formed in the Kara-Bogaz-Gol Gulf, salt lakes of Siberia and in China, form sequences up to 5-10 m thick where karst may develop. Due to the very high solubility of Na -sulphates, karst processes and features occurring in these rocks resemble salt karst. Thus, the term sulphate karst, although not strictly correct, is used mainly to indicate karst developed in gypsum and anhydrite.

  2. Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar)

    OpenAIRE

    Hannesson, Kirsten O.; Ytteborg, Elisabeth; Takle, Harald; Enersen, Grethe; B?verfjord, Grete; Pedersen, Mona E.

    2015-01-01

    In the present study, the distribution of sulphated glycosaminoglycans (GAGs) in the developing vertebral column of Atlantic salmon (Salmo salar) at 700, 900, 1100 and 1400?d? was examined by light microscopy. The mineralization pattern was outlined by Alizarin red S and soft structures by Alcian blue. The temporal and spatial distribution patterns of different types of GAGs: chondroitin-4-sulphate/dermatan sulphate, chondroitin-6-sulphate, chondroitin-0-sulphate and keratan sulphate were add...

  3. The reducibility of sulphuric acid and sulphate in aqueous solution

    International Nuclear Information System (INIS)

    Grauer, R.

    1991-07-01

    In connection with the Swedish project for final storage of spent fuel elements it was necessary to assess whether dissolved sulphate can corrode the copper canister. A simple reaction between copper and sulphate is thermodynamically impossible, but copper can react to give copper sulphide if an additional electron donor such as iron(II) is available. The problem was extended to the more general question of the reducibility of sulphur(VI) in dilute aqueous solution. Chemical reduction of sulphate does not take place in dilute solution at temperatures below 100 o C. In experiments on the reduction of sulphates under hydrothermal conditions a reaction only takes place at temperatures above 275-300 o C. The oxidising action of sulphuric acid on metals becomes perceptible only at acid concentrations over 45-50%. In experiments on the cathodic reduction of 74% sulphuric acid the formation of hydrogen sulphide and elementary sulphur starts, depending on the current density, at 50-130 o C, and polarographic measurements suggest that the reducible species is not the hydrogen sulphate ion but molecular sulphuric acid. The resistance of copper to oxygen-free sulphuric acid up to a concentration of 60% is well-known. Numerous processes in industrial electrochemistry take place in sulphuric acid or sulphate electrolytes. The reversible metal/metal-sulphate electrodes of lead and cadmium are unstable relative to the corresponding metal sulphides. Nevertheless the reversible lead sulphate electrode does not fail from sulphide formation. All these facts confirm that sulphur(VI) in dilute solution is completely inert towards chemical reducing agents and also to cathodic reduction. Thus corrosion of copper by sulphate under final-storage conditions and in the absence of sulphate reducing bacteria can be almost certainly be ruled out. (author) 5 figs., 85 refs

  4. Removal heavy metals and sulphate from waste waters by sulphate-reducing bacteria

    Directory of Open Access Journals (Sweden)

    Kušnierová Mária

    2000-09-01

    Full Text Available This article is devoted to the process of bacterial sulphate reduction, which is used to removal of heavy metals and sulphate ions from waste waters.The life of animals and plants depends on the existence of microscopic organisms – microorganisms (MO, which play an important role in cycle changes of biogenic elements on the earth. The sulphur cycle in the nature is considered as one of the oldest and most significant biological systems (Fig. 1. The sulphate-reducing bacteria (SRB miss the assimilatory part of the cycle and produce sulphides. The microbial population of this dissimilatory part is called “sulfuretum”. The SRB can be found in anaerobic mud and sediments of freshwater, thermal or non-thermal sulphur springs, mining waters from sulphide deposits, oil deposits, sea and ocean beds, and in the gastrointestinal tract of man and animals. The SRB represent a group of chemoorganotrophic, strictly anaerobic and gramnegative bacteria, which exhibit a great morphological and physiological diversity. Despite of their considerable morphological variety, they have one property in common, which is the ability to utilise preferentially sulphates (occasionally sulphites, thiosulphates, tetrathionates as electron acceptors, which are reduced to sulphides, during anaerobic respiration. The electron donors in these processes are simple organic compounds as lactate, malate, etc.,(heterotrophically reduction or gaseous hydrogen (autotrophically reduction. SRB can produce a considerable amount of hydrogen sulphide, which reacts easily in aqueous solution with the cations of heavy metals, forming metal sulphides that have low solubility. The bacterial sulphate reduction can be used for the treatment of acid mine drainage waters, which is considered to be the major problem associated with mining activities.In order to remove heavy metals from waste waters, e.g., from galvanizing plants, mine waters (Smolnik, Šobov locality and metallurgic plants (works

  5. A new paramagnetic center of copper ion γ-irradiated phosphate glasses

    International Nuclear Information System (INIS)

    Bogomolova, L.D.; Fedorov, A.G.; Jachkin, V.A.; Lazukin, V.N.; Pavlushkina, T.K.

    1981-01-01

    In the present paper are shown the results of EPR and optical absorption investigations of copper ions in γ-irradiated sodium-phosphate glasses and in MO-P 2 O 5 glasses (M = MG,Ca, Sr, Zn, Ba) containing copper and comparisons are made with the data for sodium-silicate glasses. (orig./HOF)

  6. Glass consistency and glass performance

    International Nuclear Information System (INIS)

    Plodinec, M.J.; Ramsey, W.G.

    1994-01-01

    Glass produced by the Defense Waste Processing Facility (DWPF) will have to consistently be more durable than a benchmark glass (evaluated using a short-term leach test), with high confidence. The DWPF has developed a Glass Product Control Program to comply with this specification. However, it is not clear what relevance product consistency has on long-term glass performance. In this report, the authors show that DWPF glass, produced in compliance with this specification, can be expected to effectively limit the release of soluble radionuclides to natural environments. However, the release of insoluble radionuclides to the environment will be limited by their solubility, and not glass durability

  7. Colloidal glasses

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Colloidal glasses. Glassy state is attained when system fails to reach equilibrium due to crowding of constituent particles. In molecular glasses, glassy state is reached by rapidly lowering the temperature. In colloidal glasses, glassy state is reached by increasing the ...

  8. Modeling of evaporation processes in glass melting furnaces

    NARCIS (Netherlands)

    Limpt, van J.A.C.

    2007-01-01

    The majority of glass furnaces worldwide, apply fossil fuel combustion to transfer heat directly by radiation from the combustion processes to the melting batch and glass melt. During these high temperature melting processes, some glass components, such as: sodium, potassium, boron and lead species

  9. Extraction of uranium and copper from sulphate leach liquors of West Central Sinai uraniferrous siltstone of Egypt

    International Nuclear Information System (INIS)

    Amer, T.E.; Mahdy, M.A.; El-Hazek, N.T.; El Bayoumi, R.M.; Hassanein, S.

    2000-01-01

    Extraction of uranium and copper from sulphate leach liquors of west central Sinai ore samples were performed using solvent extraction technique. Sulphate leach solutions were processed for the extraction of copper using 3% v/v LIX 973N. Copper extractions higher than 98.1% were obtained. Then, uranium was extracted using a tertiary amine. Two amines have been studied 2% v/v tri-n-octyl amine and 1.5% Alamine 336. Parameters studied included solvents concentration, contact time and solution pH. Stripping of uranium and copper were studied using sodium carbonate and sulphuric acid, respectively. Conditions were established for determining the number of stages required for extraction and stripping of copper and uranium through the construction of the corresponding McCabe-Theile diagrams. The results obtained have been utilized to formulate a proposed flowsheet for the production of uranium and copper from west central Sinai ore samples. (author)

  10. Low sodium diet (image)

    Science.gov (United States)

    ... for you. Look for these words on labels: low-sodium, sodium-free, no salt added, sodium-reduced, ... for you. Look for these words on labels: low-sodium, sodium-free, no salt added, sodium-reduced, ...

  11. 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

  12. Evidence for biological activity in mineralization of secondary sulphate deposits in a basaltic environment: implications for the search for life in the Martian subsurface

    Science.gov (United States)

    Richardson, C. Doc; Hinman, Nancy W.; Scott, Jill R.

    2013-10-01

    Evidence of microbial activity associated with mineralization of secondary Na-sulphate minerals (thenardite, mirabilite) in the basaltic subsurface of Craters of the Moon National Monument (COM), Idaho were examined by scanning electron microscopy, X-ray diffraction, laser desorption Fourier transform ion cyclotron resonance mass spectrometry (LD-FTICR-MS), Fourier transform infrared spectroscopy (FTIR) and isotope ratio mass spectrometry. Peaks suggestive of bio/organic compounds were observed in the secondary Na-sulphate deposits by LD-FTICR-MS. FTIR provided additional evidence for the presence of bio/organic compounds. Sulphur fractionation was explored to assist in determining if microbes may play a role in oxidizing sulphur. The presence of bio/organic compounds associated with Na-sulphate deposits, along with the necessity of oxidizing reduced sulphur to sulphate, suggests that biological activity may be involved in the formation of these secondary minerals. The secondary Na-sulphate minerals probably form from the overlying basalt through leached sodium ions and sulphate ions produced by bio-oxidation of Fe-sulphide minerals. Since the COM basalts are one of the most comparable terrestrial analogues for their Martian counterparts, the occurrence of biological activity in the formation of sulphate minerals at COM has direct implications for the search for life on Mars. In addition, the presence of caves on Mars suggests the importance of these environments as possible locations for growth and preservation of microbial activity. Therefore, understanding the physiochemical pathways of abiotic and biotic mineralization in the COM subsurface and similar basaltic settings has direct implications for the search for extinct or extant life on Mars.

  13. Isotopic evolution of aqueous sulphate in northern Chile water

    International Nuclear Information System (INIS)

    Aravena, R.; Suzuki, O.; Fritz, P.; Pena, H.; Rauert, W.

    1987-01-01

    Full text: The extremely arid condition of northern Chile is the main obstacle to the present and future development of urban centres and economic activities in the region. The existing water resources are scarce. During the last decade, isotope techniques have been applied to investigate aspects such as the origin and residence time of the groundwater, these being extremely important for water development and water management. This paper presents 18 O and 34 S data in aqueous sulphate, as well as 18 O, 2 H, and 3 H from springs, rivers and groundwater samples of the Pampa del Tamarugal and Salar de Llamara basins. The principal aim of this study was to investigate the isotope evolution of the sulphate, the origin of the sulphur, the groundwater flow path, and the possibility of using the 18 O of the sulphate as a tracer for estimation of the residence time of the groundwater. Springs that have their recharge area in the high Altiplano (Salar del Huasco basin) show δ values between +5.0 per mille and +6.0 per mille for the 18 O and +5.0 per mille and +9.0 per mille for the 34 S isotope. Springs from lower altitude, show an isotope content between + 8.6 per mille and + 10.6 per mille for 18 O and +7.4 per mille and + 11.7 per mille for 34 S. The groundwaters in the Pampa aquifers, based on their hydrogen and oxygen isotope composition, are associated with different recharge areas. However, these waters show an isotope range for the sulphate similar to .he one of the springs, and no clear relationships are observed between isotope content, flow path and residence time. This pattern could be related to the poorly defined aquifer systems present in the Pampa. The Llamara groundwaters have a uniform isotope content and are the most enriched in the region (δ 18 O = -6.0 per mille and δ 2 H = -50 per mille). The isotope composition of their sulphate compares well with the Pampa groundwater, indicating a similar sulphate source. The isotope composition of gypsum

  14. Simple and rapid method on High Performance Liquid Chromatography for simultaneous determination of benzylpenicillin potassium, streptomycin sulphate and related substances in Ascomicin – a veterinary use ointment

    Directory of Open Access Journals (Sweden)

    Neagu Maria

    2015-06-01

    Full Text Available A new simple, rapid, accurate and precise High – Performance Liquid Chromatography (HPLC method for determination of benzylpenicillin potassium and streptomycin sulphate in Ascomicin ointment was developed and validated. The method can be used for the detection and quantification of known and unknown impurities and degradation products in this pharmaceutical product during routine analysis and also for stability studies in view of its capability to separate degradation products. The method was validated for accuracy, precision, specificity, robustness and quantification limits according to ICH Guidelines. The estimation of benzylpenicillin potassium and streptomycin sulphate was done by Waters HPLC 2695. The chromatographic conditions comprised a reverse-phased C18 column (5 µm particle size, 250 mm×4.6 mm i.d. with a mobile phase consisting of a mixture of solution in water containing 0.025 M of sodium phosphate dibasic and 0.02 of sodium hexansulfonate adjusted to pH 6.0 with 22.5 g/lsolution of phosphoric acid and acetonitrile in gradient elution. The flow rate was 0.8 ml/min. Standard curves were linear over the concentration range of 5.00 µg/ml to 5.00 mg/ml for streptomycin sulphate and 3.26 µg/ml to 3.26 mg/ml for benzylpenicillin potassium. Statistical analyses proved the method was precise, reproducible, selective, specific and accurate for analysis of benzylpenicillin potassium, streptomycin sulphate and related substances.

  15. Hidden Sodium

    Centers for Disease Control (CDC) Podcasts

    2013-03-04

    In this podcast, learn about reducing sodium intake by knowing what to eat and the main sources of sodium in the diet. It's important for a healthy lifestyle.  Created: 3/4/2013 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 3/4/2013.

  16. Dietary sodium

    DEFF Research Database (Denmark)

    Graudal, Niels

    2015-01-01

    The 2013 Institute of Medicine (IOM) report "Sodium Intake in Populations: Assessment of Evidence" did not support the current recommendations of the IOM and the American Heart Association (AHA) to reduce daily dietary sodium intake to below 2,300 mg. The report concluded that the population...

  17. Lead-iron phosophate glass

    International Nuclear Information System (INIS)

    Sales, B.C.; Boatner, L.A.

    1988-01-01

    The lead-iron phosphate nuclear waste glasses (LIPNWG) are the subject of the present chapter. They were discovered in 1984 while the authors were attempting to find a sintering aid for certain types of crystalline monazite ceramic high-level nuclear waste forms. In the present chapter, the term waste glass is synonymous with nuclear waste glass (NWG), and the acronym LIP is often used for lead-iron phosphate. Lead-iron phosphate glasses, like many of the previously studied phosphate glasses, are corrosion resistant in aqueous solutions at temperatures below 100 degrees C, and they can be melted and poured at temperatures that are relatively low in comparison with the processing temperatures required for current silicate glass compositions. Unlike the phosphate glasses investigated previously, however, LIPNWGs do not suffer from alteration due to devitrification during realistic and readily, achievable cooling periods. Additionally, lead-iron phosphate glass melts are not nearly as corrosive as the sodium phosphate melts investigated during the 1960s; and, therefore, they can be melted and processed using crucibles made from a variety of materials

  18. Treatment with magnesium sulphate in pre-term birth

    DEFF Research Database (Denmark)

    Wolf, Hans; Hegaard, H K; Greisen, G

    2012-01-01

    Premature birth increases a child's risk of cerebral palsy and death. The aim of this work is to investigate the association between treatment with magnesium sulphate during premature deliveries and infants' cerebral palsy and mortality through a meta-analysis of observational studies....... A comprehensive search of the Cochrane Library, EMBASE and the PubMed database from their inceptions to 1 October, 2010 using the keywords 'magnesium sulphate, children/infant/pre-term/premature and cerebral palsy/mortality/morbidity/adverse effects/outcome' identified 11 reports of observational studies. Two...... authors working independently extracted the data. A meta-analysis of the data found an association between magnesium sulphate treatment and a significantly reduced risk of mortality (RR 0.73; 95% CI 0.61-0.89) and cerebral palsy (OR 0.64; 95% CI 0.47-0.89). Antenatal treatment with magnesium sulphate...

  19. Mechanism of protection of adenosine from sulphate radical anion ...

    Indian Academy of Sciences (India)

    Unknown

    Keywords. Repair by caffeic acid; repair of adenosine radicals; oxidation by sulphate radical anions. ... known that hydroxycinnamic acids are natural anti- oxidants ... acid. 2. Experimental ..... ously and independently under kinetic conditions at.

  20. Effects of agmatine sulphate on facial nerve injuries.

    Science.gov (United States)

    Surmelioglu, O; Sencar, L; Ozdemir, S; Tarkan, O; Dagkiran, M; Surmelioglu, N; Tuncer, U; Polat, S

    2017-03-01

    To evaluate the effect of agmatine sulphate on facial nerve regeneration after facial nerve injury using electron and light microscopy. The study was performed on 30 male Wistar albino rats split into: a control group, a sham-treated group, a study control group, an anastomosis group, and an anastomosis plus agmatine sulphate treatment group. The mandibular branch of the facial nerve was dissected, and a piece was removed for histological and electron microscopic examination. Regeneration was better in the anastomosis group than in the study control group. However, the best regeneration findings were seen in the agmatine sulphate treatment group. There was a significant difference between the agmatine group and the others in terms of median axon numbers (p Agmatine sulphate treatment with anastomosis in traumatic facial paralysis may enhance nerve regeneration.

  1. Short communication: Use of calcium sulphate dihydrate as an ...

    African Journals Online (AJOL)

    flocculant alternative to the conventional use of aluminium sulphate in the primary treatment of wastewater was evaluated using a jar test apparatus. Samples from the State Water Commission (CEA) in Queretaro, Mexico, were collected for the ...

  2. Anodically generated manganese(III) sulphate for the oxidation of ...

    Indian Academy of Sciences (India)

    Unknown

    oxidation of dipeptides in aqueous sulphuric acid medium: A kinetic study ... acetic acid (TFA) and N-methylmorpholine (NMM) were purchased ... and chloroform–methanol– acetic acid .... tion), manganese(II) sulphate and water (to keep the.

  3. Decolourisation and degradation of textile dyes using a sulphate ...

    African Journals Online (AJOL)

    SERVER

    2008-01-18

    Jan 18, 2008 ... Full Length Research Paper ... and microflora that augmented a sulphate reducing bacteria (SRB) consortium. ... and degradation of aromatic compounds from the deco- ... ed that aromatic amines are toxic, carcinogenic and.

  4. Anthropogenic influence on the distribution of tropospheric sulphate aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Langner, J; Rodhe, H; Crutzen, P J; Zimmermann, P [Swedish Meteorological and Hydrological Institute, Norrkoeping (Sweden)

    1992-10-22

    Human activities have increased global emissions of sulphur gases by about a factor of three during the past century, leading to increased sulphate aerosol concentrations, mainly in the Northern Hemisphere. Sulphate aerosols can affect the climate directly, by increasing the backscattering of solar radiation in cloud-free air, and indirectly, by providing additional cloud condensation nuclei. Here a global transport-chemistry model is used to estimate the changes in the distribution of tropospheric sulphate aerosol and deposition of non-seasalt sulphur that have occurred since pre-industrial times. The increase in sulphate aerosol concentration is small over the Southern Hemisphere oceans, but reaches a factor of 100 over northern Europe in winter. Calculations indicate, however, that at most 6% of the anthropogenic sulphur emissions is available for the formation of new aerosol particles. This is because about one-half of the sulphur dioxide is deposited on the Earth's surface, and most of the remainder is oxidized in cloud droplets so that the sulphate becomes associated with pre-existing particles. Even so, the rate of formation of new sulphate particles may have doubled since pre-industrial times. 18 refs., 3 figs.

  5. Mesophilic and thermophilic anaerobic digestion of sulphate-containing wastewaters.

    Science.gov (United States)

    Colleran, E; Pender, S

    2002-01-01

    The effect of sulphate at an influent chemical oxygen demand (COD):sulphate ratio of 4 on the operational performance of anaerobic hybrid reactors treating molasses wastewater was investigated under mesophilic and thermophilic conditions in a long-term laboratory-scale study over a 1,081 day period. The presence of sulphate reduced the COD removal efficiency under both mesophilic and thermophilic conditions. At 55 degrees C, effluent acetate levels were consistently greater than 4000 mg l(-1) indicating that thermophilic acetate-utilising methane-producing bacteria (MPB) or sulphate-reducing bacteria (SRB) had not developed in the reactor under the conditions applied. At 37 degrees C, acetate was exclusively utilised by acetoclastic methanogens, whereas H2-utilising SRB predominated over H2-utilising MPB in the competition for hydrogen. By contrast, hydrogenotrophic MPB were shown to outcompete H2-utilising SRB during long-term thermophilic operation. 16SrDNA analysis of the seed sludge and reactor biomass on conclusion of the 37 degrees C and 55 degrees C trials illustrated that the dominant methanogen present on conclusion of the thermophilic trial in the absence of influent sulphate was related to Methanocorpusculum parvuum, and was capable of growth on both acetate and hydrogen. By contrast, an organism closely related to Methanobacterium thermoautotrophicum was the dominant methanogen present in the sulphate-fed reactor on completion of the thermophilic trial.

  6. Recycle Glass in Foam Glass Production

    DEFF Research Database (Denmark)

    Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

    The foam glass industry turn recycle glass into heat insulating building materials. The foaming process is relative insensitive to impurities in the recycle glass. It is therefore considered to play an important role in future glass recycling. We show and discuss trends of use of recycled glasses...... in foam glass industry and the supply sources and capacity of recycle glass....

  7. Demonstration of immunogenic keratan sulphate in commercial chondroitin 6-sulphate from shark cartilage. Implications for ELISA assays

    DEFF Research Database (Denmark)

    Møller, H J; Møller-Pedersen, T; Damsgaard, T E

    1995-01-01

    The prototype monoclonal keratan sulphate (KS) antibody 5D4 that is widely used for detection of KS in tissues and biological fluids reacts strongly with commercial low grade shark cartilage chondroitin 6-sulphate. Characterization of the immunogenic material by chondroitinase ABC digestion, ELISA...... inhibition studies, immunoblotting and HPLC analyses confirmed the presence of substantial amounts of KS, probably as a large proteoglycan (> 120 kDa). Commercial and heterogenic glycosaminoglycan preparations therefore must be used with great caution in immunological analyses. On the other hand the shark...... cartilage chondroitin 6-sulphate is an easy accessible source of immunogenic KS that can be used as a reference standard and as coating antigen in KS-ELISAs. The concentration of immunogenic KS in synovial fluid measured with an ELISA based solely on reagents of shark cartilage chondroitin 6-sulphate...

  8. Demonstration of immunogenic keratan sulphate in commercial chondroitin 6-sulphate from shark cartilage. Implications for ELISA assays

    DEFF Research Database (Denmark)

    Møller, H J; Møller-Pedersen, T; Damsgaard, T E

    1995-01-01

    The prototype monoclonal keratan sulphate (KS) antibody 5D4 that is widely used for detection of KS in tissues and biological fluids reacts strongly with commercial low grade shark cartilage chondroitin 6-sulphate. Characterization of the immunogenic material by chondroitinase ABC digestion, ELISA...... cartilage chondroitin 6-sulphate is an easy accessible source of immunogenic KS that can be used as a reference standard and as coating antigen in KS-ELISAs. The concentration of immunogenic KS in synovial fluid measured with an ELISA based solely on reagents of shark cartilage chondroitin 6-sulphate...... correlated well (r = 0.90) with the concentrations obtained with a traditional KS-ELISA that uses purified aggrecan as standard and coating antigen, and KS in both serum and synovial fluid could be measured with sufficient linearity....

  9. Synthesis of specifically deuterium-labelled pregnanolone and pregnanediol sulphates for metabolic studies in humans.

    Science.gov (United States)

    Baillie, T A; Sjövall, J; Herz, J E

    1975-10-01

    A synthesis is reported of 3beta-hydroxy-5alpha-pregnan-20-one sulphate and the disulphate and 3-monosulphate of 5alpha-pregnane-3beta,20alpha-diol, labelled specifically with deuterium in high isotopic purity for metabolic studies in humans. Base-catalyzed equilibration of 3beta-hydroxy-5alpha-25R-spirostan-12-one (hemcogenin, II) with deuterium oxide, followed by removal of the 12-keto group and degradation of the sapogenin side-chain afforded 3beta-hydroxy-5alpha-[11,11-2H2]pregn-16-en-20-one (VII). Further deuterium atoms were introduced at the 3alpha and 20beta positions by reductions with sodium borodeuteride and lithium aluminum deuteride, respectively. These reactions led to 3beta-hydroxy-5alpha-[3alpha,11,11-2H3]pregnan-20-one (X; isotopic purity 87.2%) and 5alpha-[3alpha,11,11,20beta-2H4]pregnane-3beta,20alpha-diol (XIV; isotopic purity 83.9%). The 3-sulphate of the pregnanolone and the 3,20-disulphate of the pregnanediol were prepared directly form the free alcohols, while the 3-monosulphate of the pregnanediol was obtained via 5alpha-[3alpha,11,11,20beta-2H4]pregnane-3beta,20alpha-diol 20-acetate (XVII).

  10. Synthesis, characterization and antimicrobial activity of dextran sulphate stabilized silver nanoparticles

    Science.gov (United States)

    Cakić, Milorad; Glišić, Slobodan; Nikolić, Goran; Nikolić, Goran M.; Cakić, Katarina; Cvetinov, Miroslav

    2016-04-01

    Dextran sulphate stabilized silver nanoparticles (AgNPs - DS) were synthesized from aqueous solution of silver nitrate (AgNO3) and dextran sulphate sodium salt (DS). The characterization of AgNPs - DS was performed by ultraviolet-visible spectroscopy (UV-VIS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and antimicrobial activity. The formation of AgNPs - DS was monitored by colour changes of the reaction mixture from yellowish to brown and by measuring the surface plasmon resonance absorption peak in UV-VIS spectra at 420 nm. The SEM analysis was used for size and shape determination of AgNPs - DS. The presence of elemental silver and its crystalline structure in AgNPs - DS were confirmed by EDX and XRD analyses. The possible functional groups of DS responsible for the reduction and stabilization of AgNPs were determinated by FTIR spectroscopy. The AgNPs - DS showed strong antibacterial activity against Staphylococcus aureus ATCC 25923, Bacillus cereus ATCC 11778, Bacillus luteus in haus strain, Bacillus subtilis ATTC 6633, Listeria monocytogenes ATCC 15313, Escherichia coli ATTC 25922, Pseudomonas aeruginosa ATTC 27853, Klebsiella pneumoniae ATTC 700603, Proteus vulgaris ATTC 8427, and antifungal activity against Candida albicans ATTC 2091.

  11. Bacterial sulphate reduction and the development of alkalinity. II. Laboratory experiments with soils

    Energy Technology Data Exchange (ETDEWEB)

    Abd-El-Malek, Y; Rizk, S G

    1963-01-01

    In waterlogged soils sulphate reduction was characterized by increases in counts of sulphate reducers, and increase in titratable alkalinity, insoluble carbonate, and soluble sulphides, and a decrease in soluble Ca/sup 2 +/ + Mg/sup 2 +/. Presence of organic matter greatly enhanced sulphate reduction. A linear relationship between the amount of sulphate reduced and increases in titratable alkalinity and insoluble carbonate were apparent. The potential effects of sulphate reduction on soil fertility through the development of alkalinity are discussed.

  12. Development of a technique for mass spectrometric measurement of δ18O of aqueous sulphate

    International Nuclear Information System (INIS)

    Kulkarni, U.P.; Sharma, Suman

    2003-01-01

    Application of stable isotopes of hydrogen and oxygen as tracers in hydrology for studying the origin of water is well established. δ 18 O of water molecule itself is used for identifying the source of water whereas δ 18 O of dissolved oxy anions (such as carbonate, phosphate, sulphate, nitrate and silicate) present in the same water reveal their source of origin. δ 18 O of SO 4 finds applications in identifying the origin of sulfate i.e. marine, marine evaporite or non-marine in nature and as a geothermometer in determining subsurface temperature of geothermal waters. A vacuum line of glass was fabricated to measure δ 18 O of aqueous sulfate. This paper deals with the technique and results of a trial with NBS-127, Sea water barium sulfate

  13. Successful Management of Phaeochromocytoma using Preoperative Oral Labetalol and Intraoperative Magnesium Sulphate; Report of four cases

    Directory of Open Access Journals (Sweden)

    Sanath Kumar B. S.

    2014-05-01

    Full Text Available Phaeochromocytoma is a rare neuroendocrine catecholamine-secreting tumour. This type of tumour poses multidimensional anaesthetic challenges as it has an unpredictable clinical course during surgical resection. The alpha-blocking agent phenoxybenzamine remained the mainstay in preoperative preparation before the introduction of beta-blocking agents. We report four cases operated between 2009–2012 at Sultan Qaboos University Hospital, Muscat, Oman. The cases were prepared with oral labetalol, as the alpha-blocking drug phenoxybenzamine was not immediately available. Responses to simulated stress were tested in the theatre before surgery. Anaesthesia was induced under invasive arterial pressure monitoring and magnesium sulphate infusion. Rare intraoperative surges in blood pressure during tumour manipulation were treated with sodium nitroprusside infusions and phentolamine boluses. All of the patients had an uneventful postoperative recovery. Preoperative treatment with labetalol has rarely been reported and can be considered as a potential therapeutic option with optimal patient monitoring if phenoxybenzamine is unavailable.

  14. Sodium Oxybate

    Science.gov (United States)

    ... or give your sodium oxybate to anyone else; selling or sharing it is against the law. Store ... dehydrogenase deficiency (an inherited condition in which certain substances build up in the body and cause retardation ...

  15. Sodium Azide

    Science.gov (United States)

    ... Exposure to a large amount of sodium azide by any route may cause these other health effects as well: Convulsions Low blood pressure Loss of consciousness Lung injury Respiratory failure leading to death Slow heart rate ...

  16. EFFECT OF SODIUM SILICATE TO SODIUM HYDROXIDE RATIOS ON DURABILITY OF GEOPOLYMER MORTARS CONTAINING NATURAL AND ARTIFICIAL POZZOLANS

    Directory of Open Access Journals (Sweden)

    F. Nurhayat Degirmenci

    2017-09-01

    Full Text Available This study aims to provide the experimental data on the sulphate and acid performance of geopolymer mortar containing pozzolanic materials such as fly ash (FA, ground granulated blast furnace slag (GGBS and natural zeolite (NZ. The alkaline solution was the combination of sodium silicate and sodium hydroxide solution with the ratio (Na ₂SiO₃/NaOH of 1.0, 2.0 and 3.0. The molarity of sodium hydroxide was fixed as 10. The performances of geopolymer mortar were measured in terms of sodium and magnesium sulphate resistance and sulphuric and hydrochlorich acid resistance with 5% and 10 % concentration after 24 weeks. The evaluations were measured as visual observation, measurement of weight change and residual compressive strength. It has been observed that Na ₂SiO₃/NaOH ratio is effective on residual compressive strength of geopolymer mortar in both sulphate and acid exposure. The higher ratio of Na ₂SiO₃/NaOH results in a higher residual compressive strength. The GGBS based geopolymer mortar has a very good resistance in acid media in terms of weight loss and residual compressive strength. The inclusion of FA in the GGBS based geopolymer mixture was found to be a suitable base of geopolymer mortar under ambient curing conditions.

  17. Cosmos & Glass

    DEFF Research Database (Denmark)

    Beim, Anne

    1996-01-01

    The article unfolds the architectural visions of glass by Bruno Taut. It refers to inspirations by Paul Sheerbart and litterature and the Crystal Chain, also it analyses the tectonic univers that can be found in the glass pavillion for the Werkbund exposition in Cologne....

  18. Glass Glimpsed

    DEFF Research Database (Denmark)

    Lock, Charles

    2015-01-01

    Glass in poetry as it reflects the viewer and as its power of reflection are both reduced and enhanced by technology.......Glass in poetry as it reflects the viewer and as its power of reflection are both reduced and enhanced by technology....

  19. Optimization study for Pb(II) and COD sequestration by consortium of sulphate-reducing bacteria

    Science.gov (United States)

    Verma, Anamika; Bishnoi, Narsi R.; Gupta, Asha

    2017-09-01

    In this study, initial minimum inhibitory concentration (MIC) of Pb(II) ions was analysed to check optimum concentration of Pb(II) ions at which the growth of sulphate-reducing consortium (SRC) was found to be maximum. 80 ppm of Pb(II) ions was investigated as minimum inhibitory concentration for SRC. Influence of electron donors such as lactose, sucrose, glucose and sodium lactate was examined to investigate best carbon source for growth and activity of sulphate-reducing bacteria. Sodium lactate was found to be the prime carbon source for SRC. Later optimization of various parameters was executed using Box-Behnken design model of response surface methodology to explore the effectiveness of three independent operating variables, namely, pH (5.0-9.0), temperature (32-42 °C) and time (5.0-9.0 days), on dependent variables, i.e. protein content, precipitation of Pb(II) ions, and removal of COD by SRC biomass. Maximum removal of COD and Pb(II) was observed to be 91 and 98 %, respectively, at pH 7.0 and temperature 37 °C and incubation time 7 days. According to response surface analysis and analysis of variance, the experimental data were perfectly fitted to the quadratic model, and the interactive influence of pH, temperature and time on Pb(II) and COD removal was highly significant. A high regression coefficient between the variables and response ( r 2 = 0.9974) corroborate eminent evaluation of experimental data by second-order polynomial regression model. SEM and Fourier transform infrared analysis was performed to investigate morphology of PbS precipitates, sorption mechanism and involved functional groups in metal-free and metal-loaded biomass of SRC for Pb(II) binding.

  20. Development Of Glass Matrices For HLW Radioactive Wastes

    International Nuclear Information System (INIS)

    Jantzen, C.

    2010-01-01

    Vitrification is currently the most widely used technology for the treatment of high level radioactive wastes (HLW) throughout the world. Most of the nations that have generated HLW are immobilizing in either borosilicate glass or phosphate glass. One of the primary reasons that glass has become the most widely used immobilization media is the relative simplicity of the vitrification process, e.g. melt waste plus glass forming frit additives and cast. A second reason that glass has become widely used for HLW is that the short range order (SRO) and medium range order (MRO) found in glass atomistically bonds the radionuclides and governs the melt properties such as viscosity, resistivity, sulphate solubility. The molecular structure of glass controls contaminant/radionuclide release by establishing the distribution of ion exchange sites, hydrolysis sites, and the access of water to those sites. The molecular structure is flexible and hence accounts for the flexibility of glass formulations to waste variability. Nuclear waste glasses melt between 1050-1150 C which minimizes the volatility of radioactive components such as Tc 99 , Cs 137 , and I 129 . Nuclear waste glasses have good long term stability including irradiation resistance. Process control models based on the molecular structure of glass have been mechanistically derived and have been demonstrated to be accurate enough to control the world's largest HLW Joule heated ceramic melter in the US since 1996 at 95% confidence.

  1. DEVELOPMENT OF GLASS MATRICES FOR HLW RADIOACTIVE WASTES

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C.

    2010-03-18

    Vitrification is currently the most widely used technology for the treatment of high level radioactive wastes (HLW) throughout the world. Most of the nations that have generated HLW are immobilizing in either borosilicate glass or phosphate glass. One of the primary reasons that glass has become the most widely used immobilization media is the relative simplicity of the vitrification process, e.g. melt waste plus glass forming frit additives and cast. A second reason that glass has become widely used for HLW is that the short range order (SRO) and medium range order (MRO) found in glass atomistically bonds the radionuclides and governs the melt properties such as viscosity, resistivity, sulphate solubility. The molecular structure of glass controls contaminant/radionuclide release by establishing the distribution of ion exchange sites, hydrolysis sites, and the access of water to those sites. The molecular structure is flexible and hence accounts for the flexibility of glass formulations to waste variability. Nuclear waste glasses melt between 1050-1150 C which minimizes the volatility of radioactive components such as Tc{sup 99}, Cs{sup 137}, and I{sup 129}. Nuclear waste glasses have good long term stability including irradiation resistance. Process control models based on the molecular structure of glass have been mechanistically derived and have been demonstrated to be accurate enough to control the world's largest HLW Joule heated ceramic melter in the US since 1996 at 95% confidence.

  2. Spin glasses

    CERN Document Server

    Bovier, Anton

    2007-01-01

    Spin glass theory is going through a stunning period of progress while finding exciting new applications in areas beyond theoretical physics, in particular in combinatorics and computer science. This collection of state-of-the-art review papers written by leading experts in the field covers the topic from a wide variety of angles. The topics covered are mean field spin glasses, including a pedagogical account of Talagrand's proof of the Parisi solution, short range spin glasses, emphasizing the open problem of the relevance of the mean-field theory for lattice models, and the dynamics of spin glasses, in particular the problem of ageing in mean field models. The book will serve as a concise introduction to the state of the art of spin glass theory, usefull to both graduate students and young researchers, as well as to anyone curious to know what is going on in this exciting area of mathematical physics.

  3. Alternative substrates of bacterial sulphate reduction suitable for the biological-chemical treatment of acid mine drainage

    Directory of Open Access Journals (Sweden)

    Alena Luptakova

    2012-12-01

    Full Text Available The impacts of AMD pollution on biological systems are mostly severe and the problem may persist from many decadesto thousands of years. Consequently AMD prior to being released into the environment must be treated to meet government standardsfor the amount of metal and non-metal ions contained in the water. One of the best available technologies for the removal of metals fromAMD is precipitation as metal sulphides. SRB applications for AMD treatment involve a few principal stages. The first stageis the cultivation of SRB i.e. the bacterial sulphate reduction. At the laboratory conditions the sodium lactate is the energetic substratefor the growth of bacteria. Its price is not economic for the application in the practice and is needed investigate the alternativesubstitutes. The aim of this work was the cultivation of SRB using the selected energetic substrates such as: calcium lactate, ethanol,saccharose, glucose and whey. Experimental studies confirm that in the regard to the amount of reduced sulphates the calcium lactateand ethanol are the best alternative substrates for the bacterial sulphate-reduction.

  4. Glass packages in interim storage

    International Nuclear Information System (INIS)

    Jacquet-Francillon, N.

    1994-10-01

    This report summarize the current state of knowledge concerning the behavior of type C waste packages consisting of vitrified high-level solutions produced by reprocessing spent fuel. The composition and the physical and chemical properties of the feed solutions are reviewed, and the vitrification process is described. Sodium alumino-borosilicate glass compositions are generally employed - the glass used at la Hague for LWR fuel solutions, for example, contains 45 % SiO 2 . The major physical, chemical, mechanical and thermal properties of the glass are reviewed. In order to allow their thermal power to diminish, the 3630 glass packages produced (as of January 1993) in the vitrification facilities at Marcoule and La Hague are placed in interim storage for several decades. The actual interim storage period has not been defined, as it is closely related to the concept and organization selected for the final destination of the packages: a geological repository. The glass behavior under irradiation is described. Considerable basic and applied research has been conducted to assess the aqueous leaching behavior of nuclear containment glass. The effects of various repository parameters (temperature, flow rate, nature of the environmental materials) have been investigated. The experimental findings have been used to specify a model describing the kinetics of aqueous corrosion of the glass. More generally all the ''source term'' models developed in France by the CEA or by ANDRA are summarized. (author). 152 refs., 33 figs

  5. Evaluation of a single-dose of intravenous magnesium sulphate for prevention of postoperative pain after inguinal surgery

    Directory of Open Access Journals (Sweden)

    Shashi Kiran

    2011-01-01

    Full Text Available This study was undertaken to study efficacy of single dose of intravenous magnesium sulphate to reduce post-operative pain in patients undergoing inguinal surgery. One hundred patients undergoing inguinal surgery were divided randomly in two groups of 50 each. The patients of magnesium sulphate group (Group-I received magnesium sulphate 50 mg/kg in 250 ml of isotonic sodium chloride solution IV whereas patients in control group (Group-II received same volume of isotonic sodium chloride over 30 minutes preoperatively. Anaesthesia was induced with propofol (2 mg/kg and pethidine (1 mg/kg. Atracurium besylate (0.5 mg/kg was given to facilitate insertion of LMA. Pain at emergence from anaesthesia and 2, 4, 6, 12 and 24 hours after surgery was evaluated. The timing and dosage of rescue analgesic during first 24 hrs after operation was noted. Pain in postop period was significantly lower in magnesium sulphate group in comparison to control group at emergence from anaesthesia and 2, 4, 6, 12 and 24 hrs postop [1.86 vs. 1.96 (P=0.138, 1.22 vs. 1.82 (P=0.001, 1.32 vs. 1.88 (P=0.000, 2.74 vs. 3.84 (P=0.000, 1.36 vs. 2.00 (P=0.000 and 0.78 vs 1.30 (P=0.000, respectively]. Patients in group-I were more sedated as compared to group-II [sedation score 1.86 vs. 1.40 (P=0.000]. Rescue analgesia requirement postoperatively in first 4, 8 and 16 hrs was significantly lower in patients of group-1 than in group- II [1.9 vs. 3.8 (P<0.05, 25.50 vs. 52.50 (P<0.05 and 0.000 vs. 7.5 (P<0.05]. Preoperative magnesium sulphate infusion decreases postop pain and requirement of rescue analgesia.

  6. Relationship between sulphate and sulphur dioxide in the air

    Energy Technology Data Exchange (ETDEWEB)

    Fugas, M; Gentilizza, M

    1978-01-01

    The relationship between the sulphate in suspended particulates and sulphur dioxide in the air was studied in various urban and industrial areas. The relationship is best described by the equation y = ax/sup b/, where y is the percentage of the sulphate S in the total S (sulphate and sulphur dioxide) and x is the concentration of the total S in the air. The regression coefficients a and b seem to be characteristics of the area. In urban areas studied so far a was between 316 and 378 and b between -0.74 and -0.83. In industrial areas polluted by dust which contains elevated concentrations of metals a was between 91 and 107 and b between -0.35 and -0.49. In the area polluted by cement dust there was practically no correlation between the sulphate S (%) and the total S, but a relatively high correlation between absolute amounts of the sulphate S and the total S. The relations indicate that the limitation of SO/sub 2/ conversion is influenced by aerosol composition. Aerosols containing certain metals may promote the conversion by a catalytic effect while alkaline substances by increasing the pH. Whether this can only happen in the plume or in the air as well remains to be clarified.

  7. Monitoring structural transformation of hydroxy-sulphate green rust in the presence of sulphate reducing bacteria

    International Nuclear Information System (INIS)

    Abdelmoula, M.; Zegeye, A.; Jorand, F.; Carteret, C.

    2006-01-01

    The activities of bacterial consortia enable organisms to maximize their metabolic capabilities. This article assesses the synergetic relationship between iron reducing bacteria (IRB), Shewanella putrefaciens and sulphate reducing bacteria (SRB) Desulfovibrio alaskensis. Thus, the aim of this study was first to form a biogenic hydroxy-sulpahte green rust GR2(SO 4 -2 ) through the bioreduction of lepidocrocite by S. putrefaciens and secondly to investigate if sulfate anions intercalated in the biogenic GR2(SO 4 -2 ) could serve as final electron acceptor for a sulfate reducing bacterium, D. alaskensis. The results indicate that the IRB lead to the formation of GR2(SO 4 -2 ) and this mineral serve as an electron acceptor for SRB. GR2(SO 4 -2 ) precipitation and its transformation was demonstrated by using X-ray diffraction (DRX), Moessbauer spectroscopy (TMS) and transmission electron spectroscopy (TEM). These observations point out the possible acceleration of steel corrosion in marine environment in presence of IRB/SRB consortia.

  8. Corrosion Performance of Inconel 625 in High Sulphate Content

    Science.gov (United States)

    Ismail, Azzura

    2016-05-01

    Inconel 625 (UNS N06625) is a type of nickel-chromium-molybdenum alloy with excellent corrosion resistance in a wide range of corrosive media, being especially resistant to pitting and crevice corrosion. However, in aggressive environment, Inconel 625 will suffer corrosion attack like other metals. This research compared the corrosion performance of Inconel 625 when exposed to higher sulphate content compared to real seawater. The results reveal that Inconel 625 is excellent in resist the corrosion attack in seawater. However, at increasing temperature, the corrosion resistance of this metal decrease. The performance is same in seawater with high sulphate content at increasing temperature. It can be concluded that sulphate promote perforation on Inconel 625 and become aggressive agents that accelerate the corrosion attack.

  9. Sulphate Removal from Water by Carbon Residue from Biomass Gasification: Effect of Chemical Modification Methods on Sulphate Removal Efficiency

    Directory of Open Access Journals (Sweden)

    Hanna Runtti

    2016-02-01

    Full Text Available Sulphate removal from mine water is a problem because traditional chemical precipitation does not remove all sulphates. In addition, it creates lime sediment as a secondary waste. Therefore, an inexpensive and environmental-friendly sulphate removal method is needed in addition to precipitation. In this study, carbon residues from a wood gasification process were repurposed as precursors to a suitable sorbent for SO42- ion removal. The raw material was modified using ZnCl2, BaCl2, CaCl2, FeCl3, or FeCl2. Carbon residues modified with FeCl3 were selected for further consideration because the removal efficiency toward sulphate was the highest. Batch sorption experiments were performed to evaluate the effects of the initial pH, initial SO42- ion concentration, and contact time on sulphate removal. The removal of SO42- ions using Fe-modified carbon residue was notably higher compared with unmodified carbon residue and commercially available activated carbon. The sorption data exhibited pseudo-second-order kinetics. The isotherm analysis indicated that the sorption data of Fe-modified carbon residues can be represented by the bi-Langmuir isotherm model.

  10. Microwave assisted synthesis of nano sized sulphate doped hydroxyapatite

    Energy Technology Data Exchange (ETDEWEB)

    Alshemary, Ammar Z.; Goh, Yi-Fan; Akram, Muhammad; Razali, Ili Rabihah [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Darul Ta’zim (Malaysia); Abdul Kadir, Mohammed Rafiq [Medical Implant Technology Group, Faculty of Biomedical Engineering and Health Science, Universiti Teknologi Malaysia,81310 UTM Skudai, Johor Darul Ta’zim (Malaysia); Hussain, Rafaqat, E-mail: rafaqat@kimia.fs.utm.my [Ibnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor DarulTa’zim (Malaysia)

    2013-06-01

    Highlights: ► Phase pure nano-sized sulphur doped hydroxyapatite has been synthesized. ► TEM analysis confirmed formation of needle shaped structure. ► Lattice parameters and cell volume increased with increase in sulphate doping. ► Crystallite size decreased as sulphate content inside the structure increased. ► Degree of crystallinity decreased with increase in sulphate substitution. - Abstract: Inorganic sulphate is required by all mammalian cells to function properly, it is the fourth most abundant anion in the human plasma. Sulphate ions are the major source of sulphur which is considered an important element for sustenance of life as it is present in the essential amino and is required by cells to function properly. In this study we have successfully substituted sulphate ions (SO{sub 4}{sup 2−}) into hydroxyapatite (Ca{sub 10}(PO{sub 4}){sub 6−x}(SO{sub 4}){sub x}(OH){sub 2−x}) lattice via ion exchange process with phosphate group. Concentration of SO{sub 4}{sup 2−} ions was varied between X = 0.05–0.5, using (Ca (NO{sub 3}){sub 2}·4H{sub 2}O), ((NH{sub 4}){sub 2}HPO{sub 4}) and (Na{sub 2}SO{sub 4}) as starting materials. X-ray diffraction (XRD), Fourier transform IR spectroscopy (FTIR), showed that the substitution of SO{sub 4}{sup 2−} ions into the lattice resulted in peak broadening and reduced peak height due to the amorphous nature and reduced crystallinity of the resulting HA powder. Transmission electron microscopy (TEM) and field emission electron microscopy (FESEM) analysis confirmed the formation of needle shaped particles of 41 nm size with homogenous and uniform distribution of element within the HA structure.

  11. Microwave assisted synthesis of nano sized sulphate doped hydroxyapatite

    International Nuclear Information System (INIS)

    Alshemary, Ammar Z.; Goh, Yi-Fan; Akram, Muhammad; Razali, Ili Rabihah; Abdul Kadir, Mohammed Rafiq; Hussain, Rafaqat

    2013-01-01

    Highlights: ► Phase pure nano-sized sulphur doped hydroxyapatite has been synthesized. ► TEM analysis confirmed formation of needle shaped structure. ► Lattice parameters and cell volume increased with increase in sulphate doping. ► Crystallite size decreased as sulphate content inside the structure increased. ► Degree of crystallinity decreased with increase in sulphate substitution. - Abstract: Inorganic sulphate is required by all mammalian cells to function properly, it is the fourth most abundant anion in the human plasma. Sulphate ions are the major source of sulphur which is considered an important element for sustenance of life as it is present in the essential amino and is required by cells to function properly. In this study we have successfully substituted sulphate ions (SO 4 2− ) into hydroxyapatite (Ca 10 (PO 4 ) 6−x (SO 4 ) x (OH) 2−x ) lattice via ion exchange process with phosphate group. Concentration of SO 4 2− ions was varied between X = 0.05–0.5, using (Ca (NO 3 ) 2 ·4H 2 O), ((NH 4 ) 2 HPO 4 ) and (Na 2 SO 4 ) as starting materials. X-ray diffraction (XRD), Fourier transform IR spectroscopy (FTIR), showed that the substitution of SO 4 2− ions into the lattice resulted in peak broadening and reduced peak height due to the amorphous nature and reduced crystallinity of the resulting HA powder. Transmission electron microscopy (TEM) and field emission electron microscopy (FESEM) analysis confirmed the formation of needle shaped particles of 41 nm size with homogenous and uniform distribution of element within the HA structure

  12. GLASS BOX

    National Research Council Canada - National Science Library

    Curtis, Laura

    2008-01-01

    The goals of this effort were to develop Glass Box capabilities to allow for the capturing of analyst activities and the associated data resources, track and log the results of automated processing...

  13. Relative leach behavior of waste glasses and naturally occurring glasses

    International Nuclear Information System (INIS)

    Adams, P.B.

    1979-01-01

    Simulated nuclear waste glasses of the sodium-borosilicate type with a low waste loading and of the zinc-borosilicate type with a high waste loading have been compared with obsidians. The resuls indicate that the waste glasses would corrode in normal natural environments at a rate of about 0.1 μm per year at 30 0 C and about 5 μm per year at 90 0 C, compared with obsidians which seem to corrode at, or less than, about 0.01 μm per year at 30 0 C and less than 1 μm per year at 90 0 C. Activation energies for reactions of the two waste glasses with pure water are about 20 kcal/g-mol. 3 figures, 7 tables

  14. Influence of glass furnace operational conditions on the evaporation from soda-lime and borosilicate glass melts.

    NARCIS (Netherlands)

    Beerkens, R.G.C.

    2000-01-01

    The evaporation of sodium and boron species from the melts in industrial glass furnaces leads to emissions of particulates (dust) and to furnace atmospheres containing reactive evaporation products. These reactive species, especially alkali vapors, can react with the superstructure refractories

  15. Sodium diethyldithiocarbamate as accelerator of the rate of copper cementation

    Directory of Open Access Journals (Sweden)

    Abeer A. El-Saharty

    2015-12-01

    Full Text Available The effects of Cu2+ ion concentration and temperature on the cementation rate of copper from copper sulphate on zinc and the effect of additives of the organic compound “sodium diethyldithiocarbamate” (NaDDC were studied. It was noticed that the cementation increases significantly by increasing the concentrations of NaDDC. The rate of cementation increased by 58.58−100.31%. Our data showed that sodium diethyldithiocarbamate reacts with the Cu2+ solution giving a complex of copper diethyldithiocarbamate, which enhances the rate of cementation.

  16. Micrometeorological measurement of the dry deposition flux of sulphate and nitrate aerosols to coniferous forest

    NARCIS (Netherlands)

    Wyers, G.P.; Duyzer, J.H.

    1997-01-01

    Dry deposition fluxes of sulphate and nitrate have been determined over a coniferous canopy using the aerodynamic gradient technique. Vertical concentration gradients of sulphate and nitrate were measured with filters; the gradient of ammonium bisulphate was measured with thermodenuders. Filter

  17. Grass-cellulose as energy source for biological sulphate removal from acid mine effluents

    CSIR Research Space (South Africa)

    Greben, HA

    2008-11-01

    Full Text Available The biological sulphate removal technology requires carbon and energy sources to reduce sulphate to sulphide. Plant biomass, e.g. grass, is a sustainable source of energy when cellulose is utilised during anaerobic degradation, producing volatile...

  18. Interdependent action of nickel sulphate and X-rays on human lymphoblastoid leukeamic cells

    International Nuclear Information System (INIS)

    Bensimon, Jacques

    1977-01-01

    In a first experiment, cells were cultured in media supplemented by nickel sulphate, irradiated in same media and cultured in same media after irradiation. In a second experiment, cells were cultured during 18hrs. in media supplemented by nickel sulphate, and then cells were washed and cultured in normal media where they were irradiated. The nickel sulphate toxicity appears as a creasing function of the nickel sulphate concentration and the nickel sulphate action endurance. The nickel sulphate toxic effect is amplified by X-rays. This amplification is a time function that depends on the X-ray dose, nickel sulphate concentration and period of time from the outset of culture to the irradiation. The nickel sulphate toxic effect appears faster when nickel works after X-rays [fr

  19. Geochemistry of fly ash from desulphurisation process performed by sodium bicarbonate

    Energy Technology Data Exchange (ETDEWEB)

    Raclavska, Helena; Matysek, Dalibor; Raclavsky, Konstantin; Juchelkova, Dagmar [VSB - Technical University Ostrava, 17. listopadu 15, 708 33 Ostrava, Poruba (Czech Republic)

    2010-02-15

    The application of NEUTREC {sup registered} technology - desulphurisation by means of sodium bicarbonate - has been tested at the Trebovice coal-fired power plant (Ostrava, Czech Republic). This technology significantly influences the chemical composition of fly ash and the leachability of total dissolved substances (TDS), e.g., sulphates, fluorides and oxyanions (Se, Sb, Cr, As), which are monitored according to the Council of the European Union Decision 2003/33/EC. An increase of TDS in the water leachate from the fly ash obtained at 60% desulphurisation was influenced by sodium content, which is present in the form of Na{sup +} ions (85-90%). The percentages of sodium sulphate and sodium carbonate were between 5 and 10% of the total sodium content. In order to decrease the leachability of TDS, sodium, sulphates and oxyanion mixtures were prepared containing a sorbent (60% bentonite) and mixed with desulphurised and non-desulphurised fly ash in various ratios. The addition of CaO resulted in the formation of a new mineral phase, burkeite. None of the applied technologies tested for the processed fly ash resulted in the preparation of a water leachate which complied in all monitored parameters to the requirements of Council Decision 2003/33 EC for nonhazardous wastes. (author)

  20. Gastrointestinal tract wall visualization and distention during abdominal and pelvic multidetector CT with a neutral barium sulphate suspension: comparison with positive barium sulphate suspension and with water.

    Science.gov (United States)

    Oliva, M R; Erturk, S M; Ichikawa, T; Rocha, T; Ros, P R; Silverman, S G; Mortele, K J

    2012-01-01

    When examining patients with contrast-enhanced multidetector-row CT, we determined if the stomach and small bowel were visualized and distended better with a neutral barium sulphate suspension than with positive barium sulphate suspension or water. After obtaining approval from our institutional review board, 156 patients (women: 84; mean age: 54 yrs) with no history of gastrointestinal tract disease were randomized prospectively to receive orally either 900 ml of neutral (0.1% w/v) barium sulphate suspension (n = 53), 900 ml of positive (2.1% w/v) barium sulphate suspension (n = 53), or 900 ml of water (n = 50), prior to undergoing contrast-enhanced abdominal and pelvic multidetector-row CT. Two independent radiologists evaluated the stomach, and small bowel, for luminal distension and wall visualization, using a five point scale. Results were compared using Kruskal-Wallis and Mann-Whitney U tests. The walls of the stomach, and small bowel were visualized better in patients who were administered neutral barium sulphate suspension than those who were administered either positive barium sulphate suspension (p barium sulphate suspension, the stomach and small bowel were distended better compared to patients administered water (p barium sulphate suspension (p contrast-enhanced abdominal and pelvic multidetector-row CT, orally administered neutral barium sulphate suspension allows the gastrointestinal tract to be visualized and distended better than either positive barium sulphate suspension, or water.

  1. Test Your Sodium Smarts

    Science.gov (United States)

    ... You may be surprised to learn how much sodium is in many foods. Sodium, including sodium chloride ... foods with little or no salt. Test your sodium smarts by answering these 10 questions about which ...

  2. The hypobranchial mucin of the whelk Buccinum undatum L. The polysaccharide sulphate component.

    Science.gov (United States)

    Hunt, S; Jevons, F R

    1966-02-01

    1. A polysaccharide sulphate has been isolated from the hypobranchial mucin of the whelk Buccinum undatum. 2. The molecular weight of this polysaccharide, which is a glucan carrying one ester sulphate group per monosaccharide residue, is 1.7x10(5). 3. Some investigations bearing on the location of the ester sulphate groups are reported. 4. The viscosity of the whole mucin has been shown to depend mainly on the glucan sulphate.

  3. The effect of water on the sulphation of limestone

    Energy Technology Data Exchange (ETDEWEB)

    Chunbo Wang; Lufei Jia; Yewen Tan; E.J. Anthony [North China Electric Power University, Baoding City (China). School of Energy and Power Engineering

    2010-09-15

    A series of tests was conducted in a thermogravimetric analyzer (TGA) to study the sulphation behaviour of limestone in the presence of water over the temperature range of 800-850{sup o}C. Four different Canadian limestones, all with a particle size range of 75-425 {mu}m, were sulphated using a synthetic flue gas with a composition of 15% CO{sub 2}, 3% O{sub 2}, 0% or 10% H{sub 2}O, 1750 ppm SO{sub 2} and the balance N{sub 2}. Water was shown to have a significant promotional effect on sulphation, especially in the diffusion-controlled stage. However, the effect of water during the kinetic-controlled stage appeared to be much less pronounced. Based on these results, it is proposed that the presence of water leads to the transient formation of Ca(OH){sub 2} as an intermediate, which in turn reacts with SO{sub 2} at a faster rate than CaO does. Alternatively stated, it appears that H{sub 2}O acts as catalyst for the sulphation reaction of CaO. 30 refs., 8 figs., 3 tabs.

  4. Growth morphology of zinc tris(thiourea) sulphate crystals

    Indian Academy of Sciences (India)

    The growth morphology of crystals of zinc tris(thiourea) sulphate (ZTS) is investigated experimentally, and computed using the Hartman–Perdok approach. Attachment energies of the observed habit faces are calculated for determining their relative morphological importance. A computer code is developed for carrying out ...

  5. Ovarian steroid sulphate functions as priming pheromone in male ...

    Indian Academy of Sciences (India)

    Unknown

    The study reveals that pre-ovulatory females of the fish Barilius bendelisis (Ham.) release sex steroids and their conjugates into the water and that a steroid sulphate of these compounds functions as a potent sex pheromone which stimulates milt production in conspecific males prior to spawning. Since males exposed to the ...

  6. Magnesium sulphate as an anticonvulsant in the management of eclampsia

    International Nuclear Information System (INIS)

    Ahmed, R.

    2004-01-01

    Objective: To evaluate the use of magnesium sulphate (MgSO/sub 4/) as an anticonvulsant in the management of eclamptic patients. Patients and Methods: Out of a total of 6050 pregnant women, 31 patients had eclampsia and were managed according to the set protocol. MgSO/sub 4/ 'Nas given to eclamptic patients according to protocol who had no contraindication to this agent. Recurrence of convulsion, side effects of magnesium sulphate, maternal and fetal outcome was noted. Results: Over two years' study period, out of 6050 patients, 31 were admitted with eclampsia (0.51 %). There was no maternal death. Out of 31 eclamptic patients only 5 patients were booked. Twenty-two patients (70.9%) were primigravida and 9 (29%) were multigravida. Seventeen (54%) were less than 20 years of age, 22 (79.9%) patients were admitted with antepartum and 6 (19.35%) had postpartum eclampsia. Magnesium sulphate was effective in 29 (93.54%) patients. Fifteen patients delivered by caesarean (C) section and 16 delivered vaginally. Twenty-nine (93.5%) babies were born alive. Two patients had recurrent convulsion i.e. 6.4%. Only one patient had respiratory depression after the use of magnesium sulphate. Conclusion: Eclampsia was well controlled by the use of MgSO/sub 4/. There were only 2 patients who had recurrence of convulsion. Convulsions were controlled in 29 (93.54%) patients despite lack of monitoring facilities of serum magnesium level. (author)

  7. Recent Insights into Cell Surface Heparan Sulphate Proteoglycans and Cancer

    DEFF Research Database (Denmark)

    Couchman, John R; Multhaupt, Hinke; Sanderson, Ralph D

    2016-01-01

    behaviour. Here, we review some recent advances, emphasising that many tumour-related functions of proteoglycans are revealed only after their modification in processes subsequent to synthesis and export to the cell surface. These include enzymes that modify heparan sulphate structure, recycling of whole...

  8. Effect of anhydrous magnesium sulphate fertilizer and cutting ...

    African Journals Online (AJOL)

    Effect of anhydrous magnesium sulphate fertilizer on Panicum maximum yield and chemical composition of the resultant herbage harvested at 3, 4 and 5 weeks of age was investigated. The treatments were labeled T1 to T6. T1 was fertilized and harvested at 3 weeks cutting interval, T2 was fertilized and harvested at 4 ...

  9. Decolourisation and degradation of textile dyes using a sulphate ...

    African Journals Online (AJOL)

    Successful decolourisation and degradation of textile dyes was achieved in a biosulphidogenic batch reactor using biodigester sludge from a local municipality waste treatment plant as a source of carbon and microflora that augmented a sulphate reducing bacteria (SRB) consortium. Orange II (O II) was decolourised by ...

  10. Decolourisation and degradation of reactive blue 2 by sulphate ...

    African Journals Online (AJOL)

    This work was performed to determine the influence of heat treatment on sewage sludge and addition of zero valent iron (ZVI) on the degradation and decolourisation of an anthraquinone dye, reactive blue 2 (RB 2). A consortium of sulphate reducing bacteria (SRB) in a biosulphidogenic batch reactor with biodigester ...

  11. Crystallisation of mixtures of ammonium nitrate, ammonium sulphate and soot

    NARCIS (Netherlands)

    Dougle, P.G.; Veefkind, J.P.; Brink, H.M. ten

    1998-01-01

    Crystallisation of laboratory aerosols of ammonium nitrate and of internal mixtures of this salt with ammonium sulphate were investigated using humidity controlled nephelometry. The aerosol was produced via nebulizing of solutions and then dried to 25% RH, which is a realistic minimum value for

  12. Biological sulphate reduction with primary sewage sludge in an ...

    African Journals Online (AJOL)

    The success of the UASB reactor depends largely on the settling properties and stability of the sludge bed which comprises the anaerobic active biomass. The solid-liquid separation behaviour of the sludge bed in 2 UASB reactors (R1 at 35oC and R2 at 20oC) fed with primary sewage sludge and sulphate was investigated ...

  13. Endogenous and bioaugmented sulphate reduction in calcareous gypsiferous soils

    NARCIS (Netherlands)

    Alfaya, F.; Cuenca-Sanchez, M.; Garcia-Orenes, F.; Lens, P.N.L.

    2009-01-01

    Gypsiferous soils have a high agricultural value, but their utilization is limited by the presence of gypsum that can induce hardpan and vertical crusting. This paper reports on sulphate reduction in this soil type as a basis of a bioremediation technology to remove the gypsum content of calcareous

  14. Inhibition of bio corrosion of steel coupon by sulphate reducing ...

    African Journals Online (AJOL)

    SRB) and Iron oxidizing bacteria (IOB) using Aloe vera (Aloe barbadensis) extract was tested. The water sample revealed a heterotrophic bacterial count of 1.7x103 cfu/ml for the sulphate reducing bacteria and 4.1x103 cfu/ml for the Iron oxidizing ...

  15. Green chemical incorporation of sulphate into polyoxoanions of ...

    Indian Academy of Sciences (India)

    Green chemical incorporation of sulphate into polyoxoanions of molybdenum to nano level ... Keywords. Polyoxometalate; green synthesis; nanostructures; surfactant. ... The effects of reaction parameters such as concentration of surfactant, temperature and pH of solution on the synthesis of nanospheres were investigated.

  16. Sensitivity and specificity of copper sulphate test in determining ...

    African Journals Online (AJOL)

    Background: The accuracy of the copper sulphate method for the rapid screening of prospective blood donors has been questioned because this rapid screening method may lead to false deferral of truly eligible prospective blood donors. Objective: This study was aimed at determining the sensitivity and specificity of copper ...

  17. Inhibition of Bio corrosion of steel coupon by sulphate reducing ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Inhibition of Bio corrosion of steel coupon by sulphate reducing bacteria and Iron oxidizing bacteria using .... Ethanol for 24 h. The extract was ... with distilled water to get a zero reading from the meter before .... Ethanol extract of musa species peels as a green corrosion ... Eco friendly extract of banana peel as corrosion ...

  18. Kinetic and Thermodynamic Studies on Adsorption of Sulphate from ...

    African Journals Online (AJOL)

    DELL USER

    22, No. 1, 2017. 39. Kinetic and Thermodynamic Studies on Adsorption of Sulphate from Aqueous Solution by. Magnetite ... poison catalysts, and affect the .... C for 1 h in a stainless steel reactor placed in a furnace ... N2 gas for 30 min. 50 ml of ...... adsorption for designing and evaluating the ... is the equilibrium liquid-phase.

  19. Feasibility of lead removal from industrial effluents by sulphate reducing bacteria

    International Nuclear Information System (INIS)

    Nunez, L. A.; Diez, M.; Rodriguez, F. J.

    2009-01-01

    Battery manufacturing wastewater contains high concentration of sulphate and lead at low pH values. Biogical treatment by anaerobic reduction of sulphate to sulphite, with organic matter as electron donor, increases alkalinity and allow precipitating lead as sulphide. the type of organic matter, COD/SO 4 ratio and lead concentration over sulphate reduction rate are investigated in this work. (Author)

  20. Theoretical and practical aspects of aqueous solution sodium silicate modifying

    Directory of Open Access Journals (Sweden)

    Mizuryaev Sergey

    2016-01-01

    Full Text Available This research deals with the use of liquid glass in industry particularly for porous filler production. The aim of this paper is to show the necessity liquid glass modification for the purpose of its rheological characteristics change for raw granules formation and providing given structure after porization. Data on chemical liquid glass modification are provided by adding sodium chloride. Moreover, inert mineral additives influence on porous filler properties are shown in this paper. The basic principles of light concrete composition selection are specified. Test results of light concrete on the developed porous sodium silicate filler are given.

  1. Hafnium in peralkaline and peraluminous boro-aluminosilicate glass, and glass subcomponents: a solubility study

    International Nuclear Information System (INIS)

    Davis, Linda L.; Darab, John G.; Qian, Maoxu; Zhao, Donggao; Palenik, Christopher S.; Li, Hong; Strachan, Denis M.; Li, Liyu

    2003-01-01

    A relationship between the solubility of hafnia (HfO2) and the host glass composition was explored by determining the solubility limits of HfO2 in peralkaline and peraluminous borosilicate glasses in the system SiO2-Al2O3-B2O3-Na2O, and in glasses in the system SiO2-Na2O-Al2O3 in air at 1450 C. The only Hf-bearing phase to crystallize in the peralkaline borosilicate melts is hafnia, while in the boron-free melts sodium-hafnium silicates crystallize. All peraluminous borosilicate melts crystallize hafnia, but the slightly peraluminous glasses also have sector-zoned hafnia crystals that contain Al and Si. The more peraluminous borosilicate glasses also crystallize a B-containing mullite. The general morphology of the hafnia crystals changes as peralkalinity (Na2O/(Na2O+Al2O3)) decreases, as expected in melts with increasing viscosity. In all of the glasses with Na2O > Al2O3, the solubility of hafnia is linearly and positively correlated with Na2O/(Na2O + Al2O3) or Na2O - Al2O3 (excess sodium), despite the presence of 5 to 16 mol% B2O3. The solubility of hafnia is higher in the sodium-aluminum borosilicate glasses than in the sodium-aluminosilicate glasses, suggesting that the boron is enhancing the effect that excess sodium has on the incorporation of Hf into the glass structure. The results of this solubility study are compared to other studies of high-valence cation solubility in B-free silicate melts. From this, for peralkaline B-bearing glasses, it is shown that, although the solubility limits are higher, the solution behavior of hafnia is the same as in B-free silicate melts previously studied. By comparison, also, it is shown that in peraluminous melts, there must be a different solution mechanism for hafnia: different than for peralkaline sodium-aluminum borosilicate glasses and different than for B-free silicate melts studied by others

  2. Glass compositions

    Energy Technology Data Exchange (ETDEWEB)

    France, P W

    1985-05-30

    A fluoride glass for use in the production of optical fibres has an enhanced D/H ratio, preferably such that OD:OH is at least 9:1. In the example, such a glass is prepared by treating with D/sub 2/O a melt comprising 51.53 mole per cent ZrF/sub 4/, 20.47 mole per cent BaF/sub 2/, 5.27 mole per cent LaF/sub 3/, 3.24 mole per cent AlF/sub 3/, and 19.49 mole per cent LiF.

  3. Diffusion and ionic conduction in oxide glasses

    International Nuclear Information System (INIS)

    Mehrer, H; Imre, A W; Tanguep-Nijokep, E

    2008-01-01

    The ion transport properties of soda-lime silicate and alkali borate glasses have been studied with complimentary tracer diffusion and impedance spectroscopy techniques in order to investigate the ion dynamics and mixed-alkali effect (MAE). In soda-lime silicate glasses the tracer diffusivity of 22 Na alkali ions is more than six orders of magnitude faster than the diffusivity of earth alkali 45 Ca ions. This observation is attributed to a stronger binding of bivalent earth alkali ions to the glass network as compared to that of alkali ions. The conductivity of the investigated standard soda-lime silicate glasses is mostly due to the high mobility of sodium ions and a temperature independent Haven ratio of about 0.45 is obtained. For single alkali sodium-borate glasses, the Haven ratio is also temperature independent, however, it is decreases with decreasing temperature for rubidium-borate glass. The MAE was investigated for Na-Rb borate glasses and it was observed that the tracer diffusivities of 22 Na and 86 Rb ions cross, when plotted as function of the relative alkali content. This crossover occurs near the Na/(Na+Rb) ratio of the conductivity minimum due to MAE. The authors suggest that this crossover and the trend of diffusion coefficients is the key to an understanding of the MAE

  4. Facing slag glass and slag glass ceramic produced from thermal power plant ash

    Energy Technology Data Exchange (ETDEWEB)

    Buruchenko, A.E.; Kolesnikov, A.A.; Lukoyanov, A.G.

    1990-10-01

    Evaluates properties of fly ash and slags from the Krasnoyarsk coal-fired power plants and their utilization for glass and ceramic glass production. Composition of a mixture of fly ash and slag was: silica 40-55%, aluminium oxides 10-40%, ferric trioxide 6-14%, calcium oxides 20-35%, magnesium oxides 3-6%, potassium oxides 0.3-1.5%, sodium oxides 0.2-05%, sulfur trioxide 0.9-5.0%. The analyzed fly ash and slags from the Krasnoyarsk plant were an economic waste material for glass production. Properties of sand, clay and other materials used in glass production and properties of glass and ceramic glass produced on the basis of fly ash and slags are analyzed. Economic aspects of fly ash and slag utilization are also evaluated. 3 refs.

  5. Measurements of natural radioactivity in historical glasses

    International Nuclear Information System (INIS)

    Kierzek, J.; Kunicki-Goldfinger, J.J.; Kasprzak, A.J.

    2000-01-01

    Natural radioactive components of historical glasses and two methods of the respective measurement of the radioactivity are discussed. The evaluation of radioactivity of glass objects using a Geiger-Mueller counter and high-resolution gamma ray spectrometry is presented. A survey of the Warsaw National Museum glass collection with a Geiger-Mueller counter allowed distinguishing the vessels made of potassium and sodium glass by their level of natural radioactivity. Gamma spectrometry, on the other hand, enables estimating a specific radionuclide content. Special attention is given to uranium glasses. One 19th century Bohemian vessel, coloured with a uranium compound, was carefully examined using gamma spectrometry. K 2 O and U content were estimated to be 16.2 and 0.33%, respectively. (orig.)

  6. The chemical durability of alkali aluminosilicate glasses

    International Nuclear Information System (INIS)

    Tait, J.C.; Mandolesi, D.L.

    1983-09-01

    The aqueous durabilities of a series of glasses based on the sodium aluminosilicate system (Na 2 O-Al 2 O 3 -SiO 2 ) have been studied. The effects of molecular substitution of K 2 O or CaO for Na 2 O, and B 2 O 3 for Al 2 O 3 have been investigated. The temperature dependence of leaching in the Na 2 O-B 2 O 3 -Al 2 O 3 -SiO 2 system was studied with glasses containing 2 wt percent simulated UO 2 fuel recycle waste. The results confirm that aluminosilicate glasses are more durable than their borosilicate counterparts. The leaching results are explained in terms of glass structure and bonding, and a general leaching mechanism for aluminosilicate glasses is presented

  7. Modelling aqueous corrosion of nuclear waste phosphate glass

    Energy Technology Data Exchange (ETDEWEB)

    Poluektov, Pavel P.; Schmidt, Olga V.; Kascheev, Vladimir A. [Bochvar All-Russian Scientific Research Institute for Inorganic Materials (VNIINM), Moscow (Russian Federation); Ojovan, Michael I., E-mail: m.ojovan@sheffield.ac.uk [Immobilisation Science Laboratory, Department of Materials Science and Engineering, University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom)

    2017-02-15

    A model is presented on nuclear sodium alumina phosphate (NAP) glass aqueous corrosion accounting for dissolution of radioactive glass and formation of corrosion products surface layer on the glass contacting ground water of a disposal environment. Modelling is used to process available experimental data demonstrating the generic inhibiting role of corrosion products on the NAP glass surface. - Highlights: • The radionuclides yield is determined by the transport from the glass through the surface corrosion layer. • Formation of the surface layer is due to the dissolution of the glass network and the formation of insoluble compounds. • The model proposed accounts for glass dissolution, formation of corrosion layer, specie diffusion and chemical reactions. • Analytical solutions are found for corrosion layer growth rate and glass components component leaching rates.

  8. New biomarkers for increased intestinal permeability induced by dextran sodium sulphate and fasting in chickens.

    Science.gov (United States)

    Gilani, S; Howarth, G S; Kitessa, S M; Tran, C D; Forder, R E A; Hughes, R J

    2017-10-01

    Increased intestinal permeability (IP) can lead to compromised health in chickens. As there is limited literature on in vivo biomarkers to assess increased IP in chickens, the objective of this study was to identify a reliable biomarker of IP using DSS ingestion and fasting models. Male Ross chickens (n = 48) were reared until day 14 on the floor pen in an animal care facility, randomized into the following groups: control, DSS and fasting (each with n = 16), and then placed in metabolism cages. DSS was administered in drinking water at 0.75% from days 16 to 21, while controls and fasted groups received water. All birds had free access to feed and water except the birds in the fasting group that were denied feed for 19.5 h on day 20. On day 21, all chickens were given two separate oral gavages comprising fluorescein isothiocyanate dextran (FITC-d, 2.2 mg in 1 ml/bird) at time zero and lactulose, mannitol and rhamnose (LMR) sugars (0.25 g L, 0.05 g M and 0.05 g R in 2 ml/bird) at 60 min. Whole blood was collected from the brachial vein in a syringe 90 min post-LMR sugar gavage. Serum FITC-d and plasma LMR sugar concentrations were measured by spectrophotometry and high-performance ion chromatography respectively. Plasma concentrations of intestinal fatty acid binding protein, diamine oxidase, tight junction protein (TJP), d-lactate and faecal α-antitrypsin inhibitor concentration were also analysed by ELISA. FITC-d increased significantly (p fasting compared with control. L/M and L/R ratios for fasting and L/M ratio for DSS increased compared with control chickens (p fasting but not DSS treatment, compared with controls. Other tests did not indicate changes in IP (p > 0.05). We concluded that FITC-d and LMR sugar tests can be used in chickens to assess changes in IP. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  9. Degradation of sodium dodecyl sulphate in water using solar driven Fenton-like advanced oxidation processes

    International Nuclear Information System (INIS)

    Bandala, Erick R.; Pelaez, Miguel A.; Salgado, Maria J.; Torres, Luis

    2008-01-01

    Synthetic wastewater samples containing a model surfactant were treated using two different Fenton-like advanced oxidation processes promoted by solar radiation; the photo-Fenton reaction and Co/PMS/UV processes. Comparison between the different experimental conditions was performed by means of the overall surfactant degradation achieved and by obtaining the initial rate in the first 15 min of reaction (IR 15 ). It was found that, for dark Fenton reaction, the maximum surfactant degradation achieved was 14% under low iron and oxidant concentration. Increasing Fenton reagents by one magnitude order, surfactant degradation achieved 63% in 60 min. The use of solar radiation improved the reaction rate by 17% under same conditions and an additional increase of 12.5% was obtained by adjusting initial pH to 2. IR 15 values for dark and irradiated Fenton reactions were 0.143 and 0.154 mmol/min, respectively, for similar reaction conditions and this value increased to 0.189 mmol/min when initial pH was adjusted. The use of the Co/PMS system allow us to determine an increase in the degradation rate, for low reaction conditions (1 mM of transition metal; 4 mM oxidant) similar to those used in dark Fenton reaction. Surfactant degradation increased from 3%, for Fenton reaction, to 44.5% in the case of Co/PMS. When solar irradiation was included in the experiments, under same reaction conditions described earlier, surfactant degradation up to 64% was achieved. By increasing Co/PMS reagent concentration by almost 9 times under irradiated conditions, almost complete (>99%) surfactant degradation was reached in 5 min. Comparing IR 15 values for Co/PMS and Co/PMS/UV, it allow us to observe that the use of solar radiation increased the degradation rate in one magnitude order when compared with dark experiments and further increase of reagent concentration increased reaction rate twice

  10. A study of the local structure around Eu3+ ions in oxide glasses using Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Todoroki, S.; Hirao, K.; Soga, N.

    1993-01-01

    The local structure around Eu 3+ ions in several oxide glasses (silicate, germanate and borophosphate glasses) was investigated by using 151 Eu Moessbauer spectroscopy. It was found that the isomer shift (IS) of silicate and borophosphate glasses was independent of the sodium content, but that of germanate glasses was not. This means the first coordination sphere around Eu 3+ ions in silicate glasses is insensitive to the composition of the glass matrix. It is assumed that, regardless of the sodium content, Eu 3+ ions in silicate glasses attract a certain amount of nonbridging oxygen (NBO, Si-O direct difference ) when incorporated stably into silicate glass matrix, because NBO is the only species donating negative charge. For germanate glasses, the behavior of IS is considered to be related to the resence of GeO 6/2 octahedra. On the basis of experimental results, the coordination models of Eu 3+ in these systems are proposed. (orig.)

  11. Effectiveness of Chlorinated Water, Sodium Hypochlorite, Sodium ...

    African Journals Online (AJOL)

    This study evaluated the efficacy of chlorinated water, sodium hypochlorite solution, sodium chloride solution and sterile distilled water in eliminating pathogenic bacteria on the surfaces of raw vegetables. Lettuce vegetables were dipped in different concentrations of chlorinated water, sodium hypochlorite solution, sodium ...

  12. Sulphate reduction and vertical distribution of sulphate-reducing bacteria quantified by rRNA slot-blot hybridization in a coastal marine sediment

    DEFF Research Database (Denmark)

    Sahm, K.; MacGregor, BJ; Jørgensen, BB

    1999-01-01

    In the past, enumeration of sulphate-reducing bacteria (SRB) by cultivation-based methods generally contradicted measurements of sulphate reduction, suggesting unrealistically high respiration rates per cell. Here, we report evidence that quantification of SRB rRNA by slot-blot hybridization......, directly above the sulphate reduction maximum. Cell numbers calculated by converting the relative contribution of SRB rRNA to the percentage of DAPI-stained cells indicated a population size for SRB of 2.4-6.1 x 10(8) cells cm(-3) wet sediment. Cellular sulphate reduction rates calculated on the basis...

  13. The effect of magnesium on partial sulphate removal from mine water as gypsum.

    Science.gov (United States)

    Tolonen, Emma-Tuulia; Rämö, Jaakko; Lassi, Ulla

    2015-08-15

    The aim of this research was to investigate the effect of magnesium on the removal efficiency of sulphate as gypsum from mine water. The precipitation conditions were simulated with MINEQL + software and the simulation results were compared with the results from laboratory jar test experiments. Both the simulation and the laboratory results showed that magnesium in the mine water was maintaining sulphate in a soluble form as magnesium sulphate (MgSO4) at pH 9.6. Thus magnesium was preventing the removal of sulphate as gypsum (CaSO4·2H2O). However, change in the lime precipitation pH from 9.6 to 12.5 resulted in magnesium hydroxide (Mg(OH)2) precipitation and improved sulphate removal. Additionally, magnesium hydroxide could act as seed crystals for gypsum precipitation or co-precipitate sulphate further enhancing the removal of sulphate from mine water. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Glass: Rotary Electric Glass Furnace

    Energy Technology Data Exchange (ETDEWEB)

    Recca, L.

    1999-01-29

    Compared to conventional gas-fired furnaces, the new rotary electric furnace will increase energy efficiency while significantly reducing air emissions, product turnaround time, and labor costs. As this informative new fact sheet explains, the thousand different types of glass optical blanks produced for the photonics industry are used for lasers, telescopes, cameras, lights, and many other products.

  15. Coastal acid sulphate soils in Poland: a review

    Directory of Open Access Journals (Sweden)

    Hulisz Piotr

    2017-03-01

    Full Text Available This paper presents the state of knowledge on coastal acid sulphate soils in Poland. The properties of these soils are closely related to the influence of brackish water from the Baltic Sea, high accumulation of organic matter and human activity. The obtained results demonstrate that the sulphide accumulation in soils refers to a relatively small areas of the Polish coastal zone with the unique and very valuable habitats. They require an adequate regulation of the water relations to avoid the risk of strong soil acidification and environmental pollution by heavy metals. Currently, there are no relevant criteria for classification of acid sulphate soil materials in the Polish Soil Classification (2011. Therefore, based on the presented data, the authors proposed to identify these features at the lower classification level (for different soil types. The criteria for the Thionic and Sulfidic qualifiers used in the WRB classification (IUSS Working Group WRB 2015 could be accepted for this purpose.

  16. Physicochemical and in vitro deposition properties of salbutamol sulphate/ipratropium bromide and salbutamol sulphate/excipient spray dried mixtures for use in dry powder inhalers.

    Science.gov (United States)

    Corrigan, Deirdre O; Corrigan, Owen I; Healy, Anne Marie

    2006-09-28

    The physicochemical and aerodynamic properties of spray dried powders of the drug/drug mixture salbutamol sulphate/ipratropium bromide were investigated. The in vitro deposition properties of spray dried salbutamol sulphate and the spray dried drug/excipient mixtures salbutamol sulphate/lactose and salbutamol sulphate/PEG were also determined. Spray drying ipratropium bromide monohydrate resulted in a crystalline material from both aqueous and ethanolic solution. The product spray dried from aqueous solution consisted mainly of ipratropium bromide anhydrous. There was evidence of the presence of another polymorphic form of ipratropium bromide. When spray dried from ethanolic solution the physicochemical characterisation suggested the presence of an ipratropium bromide solvate with some anhydrous ipratropium bromide. Co-spray drying salbutamol sulphate with ipratropium bromide resulted in amorphous composites, regardless of solvent used. Particles were spherical and of a size suitable for inhalation. Twin impinger studies showed an increase in the fine particle fraction (FPF) of spray dried salbutamol sulphate compared to micronised salbutamol sulphate. Co-spray dried salbutamol sulphate:ipratropium bromide 10:1 and 5:1 systems also showed an increase in FPF compared to micronised salbutamol sulphate. Most co-spray dried salbutamol sulphate/excipient systems investigated demonstrated FPFs greater than that of micronised drug alone. The exceptions to this were systems containing PEG 4000 20% or PEG 20,000 40% both of which had FPFs not significantly different from micronised salbutamol sulphate. These two systems were crystalline unlike most of the other spray dried composites examined which were amorphous in nature.

  17. Influence of Some Nuclear Waste on The Durability and Mechanical Properties of Borosilicate glass

    International Nuclear Information System (INIS)

    El-Alaily, N.A.

    2003-01-01

    Various glass systems have been shown to be suitable for producing waste glass forms that are thermally and mechanically stable and exhibit good chemical durability. In this study borosilicate glass containing sodium oxide and aluminum oxide was prepared as a host for high level nuclear waste. The glass durability when the samples were immersed either in distilled water or ground water at 70 degree was studied. The density, porosity and mechanical properties were also investigated. The effects of exposing the samples immersed in groundwater to gamma rays in the glass durability and all other mentioned properties were also studied. The results showed that immersing the glass in ground water causing a decrease in the glass durability. The exposure of the glass immersed in ground water to the gamma rays increases the durability of the glass. The mechanical properties of the prepared glass were good. Although these properties decrease for the corroded glass but they were still good

  18. Structure transitions between copper-sulphate and copper-chloride ...

    Indian Academy of Sciences (India)

    Administrator

    strate that co-adsorbed sulphate ions in the (√3 × √3)R30° UPD adlayer are replaced by chloride ions and, ..... phase 1 by the (5 × 5)-like chlo- ride phase 2 was mentioned in. 45,46,48,56 but not stud- ied in detail. These authors suggested that the replacement of SO. 2. 4. – .... A nonlinear regression fit of (1) to the experi-.

  19. Sulphate and desertification signals in Middle Eastern temperature trends

    International Nuclear Information System (INIS)

    Nasrallah, H.A.; Balling, R.C. Jr.

    1994-01-01

    Analysis of Middle Eastern annual temperature anomalies over the past 40 years reveals statistically significant warming over this time period of 0.07 C per decade. The warming is most pronounced over the spring season and least apparent in the winter season. Spatial analysis reveals a positive relationship between Middle Eastern warming and the degree of human-induced desertification and a negative relationship between local warming and the atmospheric concentration of sulphate

  20. Biological sulphate reduction with primary sewage sludge in an ...

    African Journals Online (AJOL)

    2009-07-31

    Jul 31, 2009 ... The success of the UASB reactor depends largely on the settling properties and stability of the sludge bed which comprises the anaerobic active biomass. The solid-liquid separation behaviour of the sludge bed in 2 UASB reactors (R1 at 35oC and. R2 at 20oC) fed with primary sewage sludge and sulphate ...

  1. Unusual pattern of leukoencephalopathy after morphine sulphate intoxication

    Energy Technology Data Exchange (ETDEWEB)

    Nanan, R.; Stockhausen, H.B. von; Petersen, B. [Children' s Hospital, University of Wuerzburg (Germany); Solymosi, L.; Warmuth-Metz, M. [Department for Neuroradiology, University of Wuerzburg (Germany)

    2000-11-01

    We report a 14-year-old girl with an unusual pattern of leukoencephalopathy after intentional intoxication with morphine sulphate tablets. Toxicological analysis showed exceedingly high levels of morphine and its metabolites. MRI disclosed a leukoencephalopathy with high signal from the centrum semiovale, corpus callosum and cerebellar white matter on T2-weighted images. These findings could be only partially explained by a hypoxic-ischaemic event; neurotoxic effects must be considered in this atypical leukoencephalopathy. (orig.)

  2. Unusual pattern of leukoencephalopathy after morphine sulphate intoxication

    International Nuclear Information System (INIS)

    Nanan, R.; Stockhausen, H.B. von; Petersen, B.; Solymosi, L.; Warmuth-Metz, M.

    2000-01-01

    We report a 14-year-old girl with an unusual pattern of leukoencephalopathy after intentional intoxication with morphine sulphate tablets. Toxicological analysis showed exceedingly high levels of morphine and its metabolites. MRI disclosed a leukoencephalopathy with high signal from the centrum semiovale, corpus callosum and cerebellar white matter on T2-weighted images. These findings could be only partially explained by a hypoxic-ischaemic event; neurotoxic effects must be considered in this atypical leukoencephalopathy. (orig.)

  3. Sodium in diet

    Science.gov (United States)

    Diet - sodium (salt); Hyponatremia - sodium in diet; Hypernatremia - sodium in diet; Heart failure - sodium in diet ... Too much sodium in the diet may lead to: High blood pressure in some people A serious buildup of fluid in people with heart failure , cirrhosis of ...

  4. Nitrate glass

    International Nuclear Information System (INIS)

    Kirilenko, I.A.; Vinogradov, E.E.

    1977-01-01

    Experimental evidence on behaviour of nitrate glasses is reviewed in terms of relationships between the presence of water in vitrescent nitrate systems and the properties of the systems. The glasses considered belong to systems of Mg(NO 3 ) 2 - Nd(NO 3 ) 3 ; Hg(NO 3 ) 2 -Nd(NO 3 ) 3 ; NaNO 3 -Mg(NO 3 ) 2 -Nd(NO 3 ) 3 ; M-Zn(NO 3 ) 3 , where M is a mixture of 20% mass NaNO 3 and 80% mass Mg(NO 3 ) 2 , and Zn is a rare earth ion. Nitrate glass is shown to be a product of dehydration. Vitrification may be regarded as a resusl of formation of molecular complexes in the chain due to hydrogen bonds of two types, i.e. water-water, or water-nicrate group. Chain formation, along with low melting points of the nitrates, hinder crystallization of nitrate melts. Provided there is enough water, this results in vitrification

  5. The microbial communities and potential greenhouse gas production in boreal acid sulphate, non-acid sulphate, and reedy sulphidic soils

    Czech Academy of Sciences Publication Activity Database

    Šimek, Miloslav; Virtanen, S.; Simojoki, A.; Chroňáková, Alica; Elhottová, Dana; Krištůfek, Václav; Yli-Halla, M.

    2014-01-01

    Roč. 466, January (2014), s. 663-672 ISSN 0048-9697 R&D Projects: GA ČR GA526/09/1570; GA MŠk LC06066 Grant - others:GAJU(CZ) GAJU 138/2010/P Institutional support: RVO:60077344 Keywords : acid sulphate soil * carbon * CARD-FISH * microorganisms * nitrogen * PLFA Subject RIV: EE - Microbiology, Virology Impact factor: 4.099, year: 2014

  6. Chemical sulphate removal for treatment of construction and demolition debris leachate.

    Science.gov (United States)

    Kijjanapanich, Pimluck; Annachhatre, Ajit P; Esposito, Giovanni; Lens, Piet N L

    2014-08-01

    Construction and demolition debris (CDD) is a product of construction, renovation or demolition activities. It has a high gypsum content (52.4% of total gypsum), concentrated in the CDD sand (CDDS) fraction. To comply with the posed limit of the maximum amount of sulphate present in building sand, excess sulphate needs to be removed. In order to enable reuse of CDDS, a novel treatment process is developed based on washing of the CDDS to remove most of the gypsum, and subsequent sulphate removal from the sulphate-rich CDDS leachate. This study aims to assess chemical techniques, i.e. precipitation and adsorption, for sulphate removal from the CDDS leachate. Good sulphate removal efficiencies (up to 99.9%) from the CDDS leachate can be achieved by precipitation with barium chloride (BaCl2) and lead(II) nitrate (Pb(NO3)2). Precipitation with calcium chloride (CaCl2), calcium carbonate (CaCO3) and calcium oxide (CaO) gave less efficient sulphate removal. Adsorption of sulphate to aluminium oxide (Al2O3) yielded a 50% sulphate removal efficiency, whereas iron oxide-coated sand as adsorbent gave only poor (10%) sulphate removal efficiencies.

  7. The action of diazoxide and minoxidil sulphate on rat blood vessels: a comparison with cromakalim.

    Science.gov (United States)

    Newgreen, D. T.; Bray, K. M.; McHarg, A. D.; Weston, A. H.; Duty, S.; Brown, B. S.; Kay, P. B.; Edwards, G.; Longmore, J.; Southerton, J. S.

    1990-01-01

    1. The actions of diazoxide and minoxidil sulphate have been compared with those of cromakalim in rat aorta and portal vein. 2. Diazoxide and minoxidil sulphate hyperpolarized the rat portal vein in a similar manner to cromakalim. 3. Cromakalim, diazoxide and minoxidil sulphate increased 42K and 86Rb efflux from rat portal vein, although minoxidil sulphate had only a small effect on 86Rb efflux. 4. Cromakalim, diazoxide and minoxidil sulphate increased 42K efflux from rat aorta but only cromakalim and diazoxide increased 86Rb efflux from this tissue. 5. Glibenclamide inhibited the relaxant actions of cromakalim, diazoxide and minoxidil sulphate on rat aorta and the increase in 42K efflux produced by these agents in this tissue. 6. Diazoxide relaxed an 80 mM KCl-induced contraction of rat aorta, whilst cromakalim and minoxidil sulphate were without effect. 7. Cromakalim, diazoxide and minoxidil sulphate had no effect on cyclic AMP or cyclic GMP concentrations in rat aorta. 8. It is concluded that diazoxide and minoxidil sulphate like cromakalim exhibit K+ channel opening properties in vascular smooth muscle. Diazoxide exerts an additional inhibitory action not related to the production of cyclic AMP or cyclic GMP. The action of minoxidil sulphate may be primarily located at a K+ channel which is relatively impermeable to 86Rb. PMID:2167738

  8. Sulphate reduction and vertical distribution of sulphate-reducing bacteria quantified by rRNA slot-blot hybridization in a coastal marine sediment

    DEFF Research Database (Denmark)

    Sahm, K.; MacGregor, BJ; Jørgensen, BB

    1999-01-01

    In the past, enumeration of sulphate-reducing bacteria (SRB) by cultivation-based methods generally contradicted measurements of sulphate reduction, suggesting unrealistically high respiration rates per cell. Here, we report evidence that quantification of SRB rRNA by slot-blot hybridization...... between 18% and 25% to the prokaryotic rRNA pool. The dominant SRB were related to complete oxidizing genera (Desulphococcus, Desulphosarcina and Desulphobacterium), while Desulpho-bacter could not be detected. The vertical profile and quantity of rRNA from SRB was compared with sulphate reduction rates......, directly above the sulphate reduction maximum. Cell numbers calculated by converting the relative contribution of SRB rRNA to the percentage of DAPI-stained cells indicated a population size for SRB of 2.4-6.1 x 10(8) cells cm(-3) wet sediment. Cellular sulphate reduction rates calculated on the basis...

  9. Sodium technology handbook

    International Nuclear Information System (INIS)

    2005-09-01

    This document was published as a textbook for the education and training of personnel working for operations and maintenances of sodium facilities including FBR plants and those engaged in R and D activities related to sodium technology. This handbook covers the following technical areas. Properties of sodium. Compatibilities of sodium with materials. Thermalhydraulics and structural integrity. Sodium systems and components. Sodium instrumentations. Sodium handling technology. Sodium related accident evaluation and countermeasures for FBRs. Operation, maintenance and repair technology of sodium facilities. Safety measures related to sodium. Laws, regulations and internal rules related to sodium. The plannings and discussions of the handbook were made in the Sodium Technology Education Committee organized in O-arai Engineering Center consisting of the representatives of the related departments including Tsuruga headquarters. Experts in various departments participated in writing individual technical subjects. (author)

  10. Structure-Property Relationships and the Mixed Network Former Effect in Boroaluminosilicate Glasses

    DEFF Research Database (Denmark)

    Zheng, Qiuju; Potuzak, Marcel; Mauro, John C.

    compositions by substituting Al2O3 for SiO2. We also investigate the various roles of sodium in the glasses including charge compensation of tetrahedral aluminum and boron atoms and formation of non-bridging oxygen. We find that mechanical properties (density, elastic moduli, and hardness), glass transition......Boroaluminosilicate glasses are important materials for various applications, e.g., liquid crystal display substrates, glass fibers for reinforcement, and thermal shock-resistant glass containers. The complicated structural speciation in these glasses leads to a mixed network former effect yielding...... nonlinear variation in many macroscopic properties. It is therefore crucial to investigate and understand structure-property correlations in boroaluminosilicate glasses. Here we study the structure-property relationships of a range of sodium boroaluminosilicate glasses from peralkaline to peraluminous...

  11. The sodium coolant

    International Nuclear Information System (INIS)

    Rodriguez, G.

    2004-01-01

    The sodium is the best appropriate coolant for the fast neutrons reactors technology. Thus the fast neutrons reactors development is intimately bound to the sodium technology. This document presents the sodium as a coolant point of view: atomic structure and characteristics, sodium impacts on the fast neutron reactors technology, chemical properties of the sodium and the consequences, quality control in a nuclear reactor, sodium treatment. (A.L.B.)

  12. Removal of nitrate and sulphate from biologically treated municipal wastewater by electrocoagulation

    Science.gov (United States)

    Sharma, Arun Kumar; Chopra, A. K.

    2017-06-01

    The present investigation observed the effect of current density ( j), electrocoagulation (EC) time, inter electrode distance, electrode area, initial pH and settling time on the removal of nitrate (NO3 -) and sulphate (SO4 2-) from biologically treated municipal wastewater (BTMW), and optimization of the operating conditions of the EC process. A glass chamber of two-liter volume was used for the experiments with DC power supply using two electrode plates of aluminum (Al-Al). The maximum removal of NO3 - (63.21 %) and SO4 2- (79.98 %) of BTMW was found with the optimum operating conditions: current density: 2.65 A/m2, EC time: 40 min, inter electrode distance: 0.5 cm, electrode area: 160 cm2, initial pH: 7.5 and settling time: 60 min. The EC brought down the concentration of NO3 - within desirable limit of the Bureau of Indian Standard (BIS)/WHO for drinking water. Under optimal operating conditions, the operating cost was found to be 1.01/m3 of water in terms of the electrode consumption (23.71 × 10-5 kg Al/m3) and energy consumption (101.76 kWh/m3).

  13. Nanostructured 3D constructs based on chitosan and chondroitin sulphate multilayers for cartilage tissue engineering.

    Directory of Open Access Journals (Sweden)

    Joana M Silva

    Full Text Available Nanostructured three-dimensional constructs combining layer-by-layer technology (LbL and template leaching were processed and evaluated as possible support structures for cartilage tissue engineering. Multilayered constructs were formed by depositing the polyelectrolytes chitosan (CHT and chondroitin sulphate (CS on either bidimensional glass surfaces or 3D packet of paraffin spheres. 2D CHT/CS multi-layered constructs proved to support the attachment and proliferation of bovine chondrocytes (BCH. The technology was transposed to 3D level and CHT/CS multi-layered hierarchical scaffolds were retrieved after paraffin leaching. The obtained nanostructured 3D constructs had a high porosity and water uptake capacity of about 300%. Dynamical mechanical analysis (DMA showed the viscoelastic nature of the scaffolds. Cellular tests were performed with the culture of BCH and multipotent bone marrow derived stromal cells (hMSCs up to 21 days in chondrogenic differentiation media. Together with scanning electronic microscopy analysis, viability tests and DNA quantification, our results clearly showed that cells attached, proliferated and were metabolically active over the entire scaffold. Cartilaginous extracellular matrix (ECM formation was further assessed and results showed that GAG secretion occurred indicating the maintenance of the chondrogenic phenotype and the chondrogenic differentiation of hMSCs.

  14. Nanostructured 3D constructs based on chitosan and chondroitin sulphate multilayers for cartilage tissue engineering.

    Science.gov (United States)

    Silva, Joana M; Georgi, Nicole; Costa, Rui; Sher, Praveen; Reis, Rui L; Van Blitterswijk, Clemens A; Karperien, Marcel; Mano, João F

    2013-01-01

    Nanostructured three-dimensional constructs combining layer-by-layer technology (LbL) and template leaching were processed and evaluated as possible support structures for cartilage tissue engineering. Multilayered constructs were formed by depositing the polyelectrolytes chitosan (CHT) and chondroitin sulphate (CS) on either bidimensional glass surfaces or 3D packet of paraffin spheres. 2D CHT/CS multi-layered constructs proved to support the attachment and proliferation of bovine chondrocytes (BCH). The technology was transposed to 3D level and CHT/CS multi-layered hierarchical scaffolds were retrieved after paraffin leaching. The obtained nanostructured 3D constructs had a high porosity and water uptake capacity of about 300%. Dynamical mechanical analysis (DMA) showed the viscoelastic nature of the scaffolds. Cellular tests were performed with the culture of BCH and multipotent bone marrow derived stromal cells (hMSCs) up to 21 days in chondrogenic differentiation media. Together with scanning electronic microscopy analysis, viability tests and DNA quantification, our results clearly showed that cells attached, proliferated and were metabolically active over the entire scaffold. Cartilaginous extracellular matrix (ECM) formation was further assessed and results showed that GAG secretion occurred indicating the maintenance of the chondrogenic phenotype and the chondrogenic differentiation of hMSCs.

  15. Iodine release from sodium pool combustion

    International Nuclear Information System (INIS)

    Sagawa, N.; Fukushima, Y.; Yokota, N.; Akagane, K.; Mochizuki, K.

    1979-01-01

    Iodine release associated with sodium pool combustion was determined by heating 20 gr sodium containing sodium iodide, which was labelled with 131 I and dissolved in the sodium in concentration of 1∼1,000 ppm, to burn on a nickel crucible in conditioned atmosphere in a closed vessel of 0.4 m 3 . Oxygen concentration was changed in 5∼21% and humidity in 0∼89% by mixing nitrogen gas and air. Combustion products were trapped by a Maypack filter composed of particle filters, copper screens and activated charcoal beds and by a glass beads pack cooled by liquid argon. Iodine collected on these filter elements was determined by radio-gas chromatography. When the sodium sample burned in the atmosphere of air at room temperature, the release fractions observed were 6∼33% for sodium and 1∼20% for iodine added in the sodium. The release iodine was present in aerosol at a ratio of 98%, and the remainder in the gas form. The release fraction of iodine trended to decrease as oxygen concentration and humidity in the atmosphere increased. No organic iodide was detected in the combustion products. (author)

  16. In vitro and in vivo evaluation of buccal bioadhesive films containing salbutamol sulphate.

    Science.gov (United States)

    Singh, Sanjay; Soni, Rajeev; Rawat, Manoj Kumar; Jain, Achint; Deshpande, Shripad Bhimarao; Deshpande, Shripad Bheemrao; Singh, Sanjeev Kumar; Muthu, Madaswamy Sona

    2010-03-01

    The aim of present study was to prepare and evaluate buccal bioadhesive films of salbutamol sulphate (SS) for the treatment of asthma. The films were designed to release the drug for a prolonged period of time so as to reduce the frequency of administration of the available conventional dosage forms of SS. The different proportions of sodium carboxymethylcellulose (SCMC) and Carbopol 940P (CP 940P) were used for the preparation of films. Carbopol was used to incorporate the desired bioadhesiveness in the films. The films were prepared by solvent casting method and evaluated for bioadhesion, in vitro drug release and anti asthmatic effect (bronchoprotection) in histamine induced bronchospasm of guinea pigs. In vitro drug release from the film was determined using a modified Franz diffusion cell while bioadhesiveness was evaluated with a modified two-arm balance using guinea pig buccal mucosa as a model tissue. Films containing SCMC : CP 940P ratio of 76 : 24 was found to be the best with moderate swelling along with favorable bioadhesion force and in vitro drug release. The drug release mechanism was found to follow non-Fickian diffusion as release mechanism. The prolonged in vivo effect (bronchoprotection) obtained from the buccal bioadhesive film of SS administered via buccal route may improve the treatment of asthmatic disorders by reducing the frequency of administration which is associated with the tolerance effect of SS. Additionally for the clinical benefit, it is also expected to reduce the major adverse effects of SS such as tachycardia and arrhythmias via buccal absorption.

  17. 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

  18. 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

  19. Unintended consequences of atmospheric injection of sulphate aerosols.

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Patrick Vane; Kobos, Peter Holmes; Goldstein, Barry

    2010-10-01

    Most climate scientists believe that climate geoengineering is best considered as a potential complement to the mitigation of CO{sub 2} emissions, rather than as an alternative to it. Strong mitigation could achieve the equivalent of up to -4Wm{sup -2} radiative forcing on the century timescale, relative to a worst case scenario for rising CO{sub 2}. However, to tackle the remaining 3Wm{sup -2}, which are likely even in a best case scenario of strongly mitigated CO{sub 2} releases, a number of geoengineering options show promise. Injecting stratospheric aerosols is one of the least expensive and, potentially, most effective approaches and for that reason an examination of the possible unintended consequences of the implementation of atmospheric injections of sulphate aerosols was made. Chief among these are: reductions in rainfall, slowing of atmospheric ozone rebound, and differential changes in weather patterns. At the same time, there will be an increase in plant productivity. Lastly, because atmospheric sulphate injection would not mitigate ocean acidification, another side effect of fossil fuel burning, it would provide only a partial solution. Future research should aim at ameliorating the possible negative unintended consequences of atmospheric injections of sulphate injection. This might include modeling the optimum rate and particle type and size of aerosol injection, as well as the latitudinal, longitudinal and altitude of injection sites, to balance radiative forcing to decrease negative regional impacts. Similarly, future research might include modeling the optimum rate of decrease and location of injection sites to be closed to reduce or slow rapid warming upon aerosol injection cessation. A fruitful area for future research might be system modeling to enhance the possible positive increases in agricultural productivity. All such modeling must be supported by data collection and laboratory and field testing to enable iterative modeling to increase the

  20. Design of Diclofenac Sodium Indicator Strips Using Polystyrene (PS and Polymethylmethacrylate (PMMA for Detection of Diclofenac Sodium in Traditional Pain Relief Herbal Medicines

    Directory of Open Access Journals (Sweden)

    Ibrahim Dalli

    2017-04-01

    Full Text Available Diclofenac sodium is one of analgesic which is often added to traditional pain relief herbal medicines to enhance the effects. One of qualititative method that is easy, efficient and simple testing is an indicator strip. Indicator strip based Polystyrene (PS and Polymethylmethacrylate (PMMA was made for the examination of diclofenac sodium that were misused as a drug chemical compound in traditional pain relief herbal medicine. Strip indikator was made by reagent blending method with specific reagents used, namely, copper sulphate (CuSO4, ferric chloride (FeCl3 and vanillin sulphate. The working principle of the indicator strip in detecting the presence of diclofenac sodium in herbal medicine is with the occurrence of a color reaction. The concentration of PS and PMMA was made in a variation of 5%, 7.5% and 10%, and the mixture of PS: PMMA 1: 5 and 1: 6 concecutively with a ratio of solvent: reactant 6: 4; 7: 3 and 8:2. The test results showed that the best indicator strip is PMMA-CuSO4 5% (7: 3, PMMA-FeCl3 5% (7: 3 and PMMA-Vanillin sulphate 7.5% (7: 3. The detection limit and stability of the strip indicators PMMA-CuSO4 5% (7: 3 are at 50 ppm and is stable up to 29 weeks, PMMA-FeCl3 5% (7: 3 has a detection limit 12,500 ppm and is stable up to 29 weeks, and PMMA-vanillin sulphate 7,5% (7: 3 has a detection limit 500 ppm and is stable up to 29 weeks. The results showed that the indicator strip can be used as an alternative method to detect diclofenac sodium in herbal medicine and finally controlling addition of chemicals in to herbal medicine.

  1. Prediction models of mechanical properties for pet-mortar composite in sodium sulphateaggressive mediums

    Directory of Open Access Journals (Sweden)

    Kazi Tani Nabil

    2018-01-01

    Full Text Available In this research, an investigation was carried out on the effect of sodium sulphate attack on the durability of composites produced with waste polyethylene terephthalate (PET. Experiments were accomplished on limestone sand and cement mortars where the blended Portland cement was partially replaced by various volume fractions of waste PET particles (6%, 12% and 17%. The test solutions used to supply the sulphate ions and cations were 5%sodium sulphate solution. Compressive strengths measured on specimens were used to assess the changes in the mechanical properties of PET-mortars exposed to sulphate attack at different ages, mainly the Young modulus of elasticity. Based on experimental compressive tests on PETMortar composite specimens and there densities, the evolution of Young modulus of elasticity has been analyzed in accordance with normative models given by (ACI-318 and (BS-8110 codes of practice. In addition, a comparative study has been carried out for corrosion resistance coefficients K of unmodified mortar to those modified with waste PET particles. It can be noticed that, for the composite immersed in a corrosive Na2SO4 solution, the corrosion resistance coefficients decrease with the increase of the immersion period. The corrosion sulphate resistance K based on Young modulus before and after immersion of PET-mortar composites is better than that of the control mortar. Therefore, for safety considerations of PET-mortar composites use, ACI 318 is recommended code for design and investigation works. Also, it can be concluded that adding waste PET by volume fractions (6%, 12% and 17% to blend Portland cement renders this cement more resistant to the sodium sulphate aggressive medium. Therefore, composites materials based waste PET aare often presented as the materials of the future because of their potential for innovation and the advantages they offer. In fact, using waste PET as cement substitutes reduces the energy consumption. These

  2. Serum and urinary oestrone sulphate in pregnancy and delivery measured by a direct radioimmunoassay

    International Nuclear Information System (INIS)

    Honjo, Hideo; Kitawaki, Jo; Itoh, Masafumi; Yasuda, Jinsuke; Yamamoto, Takara; Yamamoto, Takao; Okada, Hiroji; Ohkubo, Tadashi; Nambara, Toshio

    1986-01-01

    Serum and urinary levels of oestrone sulphate in pregnancy and delivery were measured by a direct radioimmunoassay without hydrolysis. the serum and urinary oestrone sulphate increased as pregnancy progressed. the mean level of serum oestrone sulphate increased to the highest peak of 494 pmol/ml at the 35th gestational week and then decreased. The mean level of urinary oestrone sulphate increased to the highest peak of 1.28 μmol/l at the 34th gestational week and the decreased. At vaginal deliveries, the mean level of maternal peripheral serum oestrone sulphate increased hourly at as high a level as 979 pmol/ml. The mean serum level of oestrone sulphate was 204 pmol/ml in the umbilical artery and 145 pmol/ml in the umbilical vein. At Caesarean section, on the other hand, the maternal peripheral serum level of oestrone sulphate averaged 362 pmol/ml. The mean serum levels of oestrone sulphate wre 90.7 pmol/ml and 171 pmol/ml in the umbilical artery and umbilical vein, respectively. These results suggest a maternal origin of oestrone sulphate in pregnancy, with fluctuations in the levels being of interest in relation to labour pain. (author)

  3. Recovery of uranium from sulphate solutions containing molybdenum

    International Nuclear Information System (INIS)

    Weir, D.R.; Genik-Sas-Berezowsky, R.M.

    1983-01-01

    A process for recovering uranium from a sulphate solution containing dissolved uranium and molybdenum includes reacting the solution with ammonia (pH 8 to 10), the pH of the original solution must not exceed 5.5 and after the addition of ammonia the pH must not be in the vicinity of 7 for a significant time. The resultant uranium precipitate is relatively uncontaminated by molybdenum. The precipitate is then separated from the remaining solution while the pH is maintained within the stated range

  4. Effect of radiation on activity of sulphate reducing bacteria

    International Nuclear Information System (INIS)

    Agaev, N.M.; Smorodin, A.E.; Gusejnov, M.M.

    1985-01-01

    The effect of γ-radiation on activity of sulphate reducing bacteria has been studied. Concentration of biogenic hydrogen, generated in the medium, is the main criterion, characterizing corrosion activity of the bacteria studied. The developed method of suppression of active development of sulfate reducing bacteria considerably reduces, and at lethal doses of γ-radiation eliminates altogether the bacteria activity and formation of the main corrosion agent-hydrogen sulphide-in the medium and that, in its turn, liquidates hydrogen sulphide corrosion

  5. Pyroelectric effect in tryglicyne sulphate single crystals - Differential measurement method

    Science.gov (United States)

    Trybus, M.

    2018-06-01

    A simple mathematical model of the pyroelectric phenomenon was used to explain the electric response of the TGS (triglycine sulphate) samples in the linear heating process in ferroelectric and paraelectric phases. Experimental verification of mathematical model was realized. TGS single crystals were grown and four electrode samples were fabricated. Differential measurements of the pyroelectric response of two different regions of the samples were performed and the results were compared with data obtained from the model. Experimental results are in good agreement with model calculations.

  6. Development and characterization of mucoadhesive buccal patches of salbutamol sulphate.

    Science.gov (United States)

    Patel, Rajesh Singh; Poddar, S S

    2009-01-01

    Mucoadhesive patch releasing the drug in the oral cavity at predetermined rate may present distinct advantages over traditional dosage forms such as tablets, gels and solutions. The present study was concerned with the preparation and evaluation of mucoadhesive buccal patches for the controlled systemic delivery of Salbutamol sulphate to avoid first pass hepatic metabolism. The developed patches were evaluated for the physicochemical, mechanical and drug release characteristics. The patches showed desired mechanical and physicochemical properties to withstand environment of oral cavity. The in-vitro release study showed that patches could deliver drug to the oral mucosa for a period of 7 h. the patches exhibited adequate stability when tested under accelerated conditions.

  7. Dielectric dispersion in pure and doped lithium rubidium sulphate

    Science.gov (United States)

    Kassem, M. E.; El-Muraikhi, M.; Al-Houty, L.; Mohamed, A. A.

    The frequency (102 - 105 Hz) dependence of the dielectric properties of lithium rubidium sulphate (LRS) are reported in the vicinity of the transition temperature Tc = 477 K. The a.c. conductivity σ(ω) shows a strong temperature dependence and weak frequency response. The dielectric constant in this region shows a strong frequency dispersion. A Cole-Cole diagram was used to determine the distribution parameter and the molecular relaxation time. The effect of doping with Dy+3, Sm+3 and V+3, was also studied. It was found that doping gives rise to localized states which produce a disorder in the structure of LiRbSO4.

  8. Interactions between cement grouts and sulphate bearing ground water

    International Nuclear Information System (INIS)

    Walton, P.L.; Duerden, S.L.; Atkins, K.M.; Majumdar, A.J.

    1989-01-01

    The physical, chemical and mineralogical properties of mixtures of Ordinary Portland cement and blastfurnace slag or pulverized fuel ash, exposed to a sulphate-bearing ground water at different temperatures and pressures, were investigated in order to assess the long term durability of cements for encapsulating radioactive waste and backfilling a repository. The effect of the ground water on the chemical and mineralogical characteristics of the cements is minimal. Calcite and C-S-H are present in all the samples and are durable throughout the test. Dimensional changes in the cements during setting and curing may cause weaknesses in the materials which may increase the effects of a percolating ground water. (author)

  9. Nuclear waste immobilization in iron phosphate glasses

    International Nuclear Information System (INIS)

    Garcia, D.A.; Rodriguez, Diego A.; Menghini, Jorge E.; Bevilacqua, Arturo

    2007-01-01

    Iron-phosphate glasses have become important in the nuclear waste immobilization area because they have some advantages over silicate-based glasses, such as a lower processing temperature and a higher nuclear waste load without losing chemical and mechanical properties. Structure and chemical properties of iron-phosphate glasses are determined in terms of the main components, in this case, phosphate oxide along with the other oxides that are added to improve some of the characteristics of the glasses. For example, Iron oxide improves chemical durability, lead oxide lowers fusion temperature and sodium oxide reduces viscosity at high temperature. In this work a study based on the composition-property relations was made. We used different techniques to characterize a series of iron-lead-phosphate glasses with uranium and aluminium oxide as simulated nuclear waste. We used the Arquimedes method to determine the bulk density, differential temperature analysis (DTA) to determine both glass transition temperature and crystallization temperature, dilatometric analysis to calculate the linear thermal expansion coefficient, chemical durability (MCC-1 test) and X-ray diffraction (XRD). We also applied some theoretic models to calculate activation energies associated with the glass transition temperature and crystallization processes. (author)

  10. Liquid sodium pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Casselman, C [DSN/SESTR, Centre de Cadarache, Saint-Paul-lez-Durance (France)

    1979-03-01

    Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

  11. Liquid sodium pool fires

    International Nuclear Information System (INIS)

    Casselman, C.

    1979-01-01

    Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

  12. CRYSTALLIZATION IN MULTICOMPONENT GLASSES

    Energy Technology Data Exchange (ETDEWEB)

    KRUGER AA; HRMA PR

    2009-10-08

    In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures involving partial crystallization. In the glass melter, crystals form and dissolve during batch-to-glass conversion, melter processing, and product cooling. Crystals often agglomerate and sink, and they may settle at the melter bottom. Within the body of cooling glass, multiple phases crystallize in a non-uniform time-dependent temperature field. Self-organizing periodic distribution (the Liesegnang effect) is common. Various crystallization phenomena that occur in glass making are reviewed.

  13. Crystallization In Multicomponent Glasses

    International Nuclear Information System (INIS)

    Kruger, A.A.; Hrma, P.R.

    2009-01-01

    In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures involving partial crystallization. In the glass melter, crystals form and dissolve during batch-to-glass conversion, melter processing, and product cooling. Crystals often agglomerate and sink, and they may settle at the melter bottom. Within the body of cooling glass, multiple phases crystallize in a non-uniform time-dependent temperature field. Self-organizing periodic distribution (the Liesegnang effect) is common. Various crystallization phenomena that occur in glass making are reviewed.

  14. Effect of the addition of Na2O on the thermal stability of alumino silicated glasses rich in rare earths

    International Nuclear Information System (INIS)

    Lassalle-Herraud, Olivier; Matecki, Marc; Glorieux, Benoit; Sadiki, Najim; Montoullout, Valerie; Dussossoy, Jean-Luc

    2006-01-01

    Alumino silicated glasses rich in rare earths have been prepared by concentrated solar way. Their recrystallization, the structural and microstructural properties as well as the mechanical and thermal properties of these glasses have been studied. The results show the effect of sodium addition on the thermal stability of the materials, the vitreous transition temperature and the recrystallization temperature. A heat treatment has allowed to reveal the formation of sodium apatite micro-crystallites and of lanthanum silicate in the glasses. (O.M.)

  15. Hydrothermal Alteration in an Acid-Sulphate Geothermal Field: Sulphur Springs, Saint Lucia

    Science.gov (United States)

    Joseph, E. P.; Barrett, T. J.

    2017-12-01

    Sulphur Springs is a vigorous geothermal field associated with the Soufrière Volcanic Centre in southern Saint Lucia. Bubbling hydrothermal pools are rich in sodium-calcium sulphate, with pHs of 3-7 and temperatures of 41-97ºC. Fumaroles have temperatures up to, and at times above, 100°C. Gases from bubbling pools and fumaroles have high contents of CO2 (601-993 mmol/mol) and H2S (3-190 mmol/mol). To investigate the nature and extent of hydrothermal alteration, detailed chemical analysis was carried out on 25 altered rocks, 10 sediments from pools and creeks in the main discharge area, and 15 little-altered rocks up to 2 km away from geothermal field. Eight altered samples were also analysed for stable isotope compositions, with mineralogy determined by X-ray diffraction and mineral liberation analysis. Least-altered host rocks comprise calc-alkaline feldspar-quartz-porphyritic dacites of near-uniform composition that form massive domes and volcaniclastic units. These rocks were emplaced 10-30 Ka ago (Lindsay et al. 2013). Within the geothermal field, the dacites have been highly altered to kaolinite, quartz, cristobalite, alunite, natroalunite, smectite, native sulphur, jarosite, gypsum and amorphous compounds. Muds from grey to blackish hydrothermal pools additionally contain iron sulphides, mainly pyrite. Despite intense alteration of the original dacites, Zr and Ti have remained essentially immobile, allowing the calculation of mass changes. Major depletions of Fe, Mg, Ca, Na and commonly Si occur over an area of at least 200 x 400 m. The most altered rocks also show losses of Al, light REE and Y, implying leaching by highly acidic waters. A few altered rocks have, however, gained Al together with Si and P. Also present are m-scale zones of silica + native sulphur, wherein the silica appears to represent a residue from the leaching of dacite, rather than a hydrothermal addition. Delta-34S values of samples containing mixtures of sulphates, native sulphur and

  16. Small liquid sodium leaks

    International Nuclear Information System (INIS)

    Dufresne, J.; Rochedereux, Y.; Antonakas, D.; Casselman, C.; Malet, J.C.

    1986-05-01

    Usually, pessimistic considerations inassessing the safety of secondary sodium loops in LMFBR reactor lead to assume guillotine rupture releasing a large amount of sodium estimate the consequences of large sodium fires. In order to reduce these consequences, one has to detect the smallest leak as soon as possible and to evaluate the future of an initial small leak. Analysis of the relationship between crack size and sodium outflow rate; Analysis of a sodium pipe with a small open crack

  17. Gasification of sulphate soap for the lime kiln

    Energy Technology Data Exchange (ETDEWEB)

    Saviharju, Kari (Valtion Teknillinen Tutkimuskeskus, Espoo (Finland). Lab. of Fuel and Process Technology); Timonen, Tuomas (Finnish Energy Economy Association, Espoo (Finland). Finnish Recovery Boiler Committee)

    1993-01-01

    Sulphate soap is a by-product of pulp mills utilized as a raw material for the chemical industry. However, this results in an increase in sulphur input of several kilograms SO[sub 2] per ADt pulp into the mill. Another increasingly interesting alternative is to utilize soap in the lime kiln of the mill. This has a positive effect, in addition to sulphur problems, on the energy balance of the mill. The crucial problem is the high Na + K content of soap, from 4 to 8%, which can result in plugging of the lime kiln. The operational problems can be avoided by gasifying the soap and by separating the inorganic materials from the product gas before the kiln. This paper describes research work on the gasification of crude sulphate soap carried out at the Technical Research Centre of Finland (VTT) over the years 1991 and 1992. This work will be continued in 1993 by focusing on specified problems, after which commercial applications should be available. (author)

  18. The Sulphate Effect on Lijiaxia Concrete Dam (China Gallery

    Directory of Open Access Journals (Sweden)

    Xufen Zhu

    2017-01-01

    Full Text Available The concrete degradation is one of the most serious problems for a dam construct during the normal operation, which determines the dam service life. Hence, it is very important to reduce the extent of the dam concrete degradation for the safety of the dam normal operation. Here, Lijiaxia hydroelectric station is taken as an example, and a comprehensive method to assess the sulphate effect on dam gallery is proposed. Eleven samples in total were taken from three difference locations by the drill bore. The microstructural investigations including X-ray fluorescence spectrometry (XRF, X-ray diffraction (XRD, scanning electron microscope (SEM, and energy dispersive spectroscopy (EDS were conducted to assess the sulphate attack and the degradation degree. Meanwhile, the water chemical analysis was applied to reveal the mechanism of concrete degradation. The experimental and analysis results indicate that the concrete degradation degree varies with the location of the samples. The components of the concrete change and the content of SO3 increase dramatically during degradation. Moreover, the mineral facies of the concrete change correspondingly, with the cement paste substituted by the calcite, calcium vitriol, and gypsum. The reinforcement and precaution measures are suggested based on the results of the degradation assessment.

  19. Polyferric sulphate: preparation, characterisation and application in coagulation experiments.

    Science.gov (United States)

    Zouboulis, A I; Moussas, P A; Vasilakou, F

    2008-07-15

    The process of coagulation is a core environmental protection technology, which is mainly used in the water or wastewater treatment facilities. Research is now focused on the development of inorganic pre-polymerised coagulants. A characteristic example is PFS (polyferric sulphate), a relatively new pre-polymerised inorganic coagulant with high cationic charge. In this paper, the role of major parameters, including temperature, types of chemical reagents, ratio r=[OH]/[Fe], rate of base addition in the preparation stages of PFS were investigated. Furthermore, the prepared PFS was characterised based on typical properties, such as the percentage of the polymerised iron present in the compound, z-potential, pH, etc. Moreover, dynamics of coagulation process were examined by means of the Photometric Dispersion Analyzer (PDA). Finally, the coagulation efficiency of PFS in treating kaolin suspension and biologically pre-treated wastewater was evaluated in comparison with the respective conventional coagulant agent. The results indicate that certain parameters, such as the r value, the rate of base addition and the duration and temperature of the polymerisation stage, significantly affected the properties of the PFS. Additionally, the prepared PFS polymerised coagulants exhibit a significantly better coagulation performance than the respective non-polymerised one, i.e. ferric sulphate.

  20. Recycling of Glass

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Damgaard, Anders

    2011-01-01

    Glass is used for many purposes, but in the waste system glass is predominantly found in terms of beverage and food containers with a relatively short lifetime before ending up in the waste. Furthermore there is a large amount of flat glass used in building materials which also ends up in the waste...... system; this glass though has a long lifetime before ending up in the waste. Altogether these product types add up to 82% of the production of the European glass industry (IPCC, 2001). Recycling of glass in terms of cleaning and refilling of bottles as well as the use of broken glass in the production...... of new glass containers is well established in the glass industry. This chapter describes briefly howglass is produced and howwaste glass is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of glass recycling....

  1. Are high rates of sulphate reduction associated with anaerobic oxidation of methane

    Energy Technology Data Exchange (ETDEWEB)

    Devol, A H; Ahmed, S I

    1981-01-01

    Classical models of sulphur diagenesis in marine sediments are based on the assumption that the rate of sulphate reduction is first order with respect to oxidizable particulate organic carbon (POC). This assumption requires that oxidizable POC, sulphate concentration and the sulphate reduction rate be highest at the top of the sulphate reduction zone and decrease exponentially with increasing sediment depth. However, to explain recent observations of concave upwards methane distributions, the anaerobic consumption of methane has been proposed. Furthermore, it has been proposed that this consumption takes place near the bottom of the sulphate reducing zone where sulphate concentrations are low. Thus, if sulphate reducing bacteria are associated with the anaerobic oxidation of methane, a peak in sulphate reduction rate might be expected in this deep consumption zone. The importance of the process in sedimentary sulphur diagenesis is indicated by calculations estimating that 30 to 75% of the downward sulphate flux at depth may be consumed by methane oxidation within this zone. We present here profiles of sulphate reduction rate in anoxic sediments that show distinct local maxima at the depth where the anaerobic oxidation of methane would be expected. Our measurements were made during July and August 1978 in Saanich Inlet, an anoxic fjord located on the south-east of Vancouver Island, British Columbia. The inlet has a shallow sill (approx 70 m) which restricts circulation of the deeper water (maximum depth 225 m) inside the basin to the extent that for about 8 months of the year the bottom waters contain hydrogen sulphide, the inlet is an ideal location for studying sedimentary sulphate reduction because reactions with oxygen and the effects of burrowing organisms can be neglected.

  2. 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......Simple sodium borosilicate and silicate glasses were melted on a very large scale (35 l Pt crucible) to prepare model glasses of optical quality in order to investigate various properties depending on their structure. The composition of the glass samples varied in a wide range: 3 to 33·3 mol% Na2O...... by impedance measurements in a wide temperature range (250 to 1450°C). The activation energies were calculated by Arrhenius plots in various temperature regions: below the glass transition temperature, Tg, above the melting point, Tl, and between Tg and Tl. Viscosity measurements were carried out...

  3. Sodium dithionite as a selective demasking agent for the complexometric determination of thallium

    Directory of Open Access Journals (Sweden)

    PRAKASH SHETTY

    2005-11-01

    Full Text Available Sodium dithionite is proposed as a new demasking agent for the rapid and selective complexometric determination of thallium(III. In the presence of diverse metal ions, thallium (III was first complexed with excess EDTA and the surplus EDTAwas then titrated with a standard zinc sulphate solution at pH 5–6 (hexamine buffer using Xylenol Orange as the indicator. The EDTAequivalent to thallium was then released selectively with sodium dithionite and back titrated with a standard zinc sulphate solution as before. Reproducible and accurate results were obtained in the range 4–100 mg of thallium with a relative error of ±27 % and a coefficient of variation (n = 6 of not more than 0.30 %. The effects of various diverse ions were studied. The method was applied to the determination of thallium in its complexes and in alloys.

  4. Correlation analysis between sulphate content and leaching of sulphates in recycled aggregates from construction and demolition wastes.

    Science.gov (United States)

    Barbudo, Auxi; Galvín, Adela P; Agrela, Francisco; Ayuso, Jesús; Jiménez, Jose Ramón

    2012-06-01

    In some recycled aggregates applications, such as component of new concrete or roads, the total content of soluble sulphates should be measured and controlled. Restrictions are usually motivated by the resistance or stability of the new structure, and in most cases, structural concerns can be remedied by the use of techniques such as sulphur-resistant cements. However, environmental risk assessment from recycling and reuse construction products is often forgotten. The purpose of this study is to analyse the content of soluble sulphate on eleven recycled aggregates and six samples prepared in laboratory by the addition of different gypsum percentages. As points of reference, two natural aggregates were tested. An analysis of the content of the leachable amount of heavy metals regulated by European regulation was included. As a result, the correlation between solubility and leachability data allow suggest a limiting gypsum amount of 4.4% on recycled aggregates. This limit satisfies EU Landfill Directive criteria, which is currently used as reference by public Spanish Government for recycled aggregates in construction works. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Removal of Pb (II from Aqueous Solutions Using Mixtures of Bamboo Biochar and Calcium Sulphate, and Hydroxyapatite and Calcium Sulphate

    Directory of Open Access Journals (Sweden)

    Ahmed Hassan

    2016-01-01

    Full Text Available Sorption characteristics of Pb(II from aqueous solutions through a low-cost adsorbent mixture comprising of Bamboo biochar (BB and Calcium Sulphate (CS, and a more expensive mixture of Hydroxyapatite (HAP and Calcium Sulphate (CS, were investigated. The effects of equilibrium contact time, and adsorbate concentration conducted in batch experiments were studied. Adsorption equilibrium was established in 40 (min. The adsorption mechanism of Pb(II from these two adsorbent mixtures was carried out through a kinetic rate order. A pseudo second-order kinetic model was applied for the adsorption processes. The model yielded good correlation (R2 >0.999 of the experimental data. Adsorption of Pb(II using (BB&CS and (HAP&CS correlated well (R2 >0.99 with both the Langmuir and Freundlich isotherm equations under the concentration range studied. Hence, the effectiveness of an inexpensive natural material (BB&CS mixture in Pb(II removal is established, and is promising for use in other heavy metal adsorptions.

  6. Phase Behavior and Rheology of Fatty Alcohol Sulphate, Fatty Alcohol Ether Sulphate from Palm based and Mixtures with other Surfactants

    International Nuclear Information System (INIS)

    Hong, L.K.; Nur Syazani Harun; Mohd Suzeren Mohd Jamil; Rahimi Mohd Yusop

    2013-01-01

    The phase diagrams of fatty alcohol sulphate (FAS)/ fatty alcohol ether sulphate (FAES)/ soap (4.5:4.5:1.0)/ propylene glycol/ water mixtures were established at 60 degree Celsius. The birefringence was observed under cross polarizers and their phases changes examined under a polarized microscope. The results showed that the liquid crystalline region for FAS and FAES occurred only in a small region. The optical patterns of lamellar liquid crystal were identified as oily streaks structure. The rheological tests of lamellar liquid crystal were carried out in the region of 4.5/ 4.5/ 1 FAES/ FAS/ soap with 0 % PG and 10 % of water. The rheological tests used were flow curve, 3 interval thixotropy test (3ITT), oscillation (dynamic test) stress sweep test and frequency sweep test measurement done using a cone-plate sensor (25 mm, 1 degree). The flow curve was fitted to a Casson model to obtain values for the consistency coefficient and the flow behavior index. The lamellar liquid crystal show typical flow behavior and stress influenced the recovery of the structure. Linear visco-elastic (LVE) range analysis show the critical stress value at 0.475%, and elastic modulus was dominant over an angular frequency range studied. (author)

  7. Modelling the competition between sulphate reducers and methanogens in a thermophilic methanol-fed bioreactor

    NARCIS (Netherlands)

    Spanjers, H.; Weijma, J.; Abusam, A.

    2002-01-01

    Sulphate can be removed from wastewater by means of biological anaerobic reduction to sulphide. The reduction requires the presence of a substrate that can serve as an electron donor. Methanol a suitable electron donor for sulphate reduction under thermophilic conditions. In an anaerobic system

  8. Magnesium sulphate for women at risk of preterm birth for neuroprotection of the fetus

    NARCIS (Netherlands)

    Doyle, Lex W.; Crowther, Caroline A.; Middleton, Philippa; Marret, Stephane; Rouse, Dwight

    2009-01-01

    Background Epidemiological and basic science evidence suggests that magnesium sulphate before birth may be neuroprotective for the fetus. Objectives To assess the effects of magnesium sulphate as a neuroprotective agent when given to women considered at risk of preterm birth. Search strategy We

  9. Treatment of acid and sulphate-rich effluents in an integrated biological/chemical process

    CSIR Research Space (South Africa)

    Maree, JP

    2004-04-01

    Full Text Available .4 g SO4/(l.d). The rate of biological sulphate removal was found to be directly related to the square root of sulphate, COD and VSS concentrations respectively, and inversely proportional to sulphide concentration. The practical value of simultaneous...

  10. Volcanic lake systems as terrestrial analogue for sulphate-rich terrains on Mars

    NARCIS (Netherlands)

    Rodríguez, A.

    2016-01-01

    Remote-sensing observations and rover missions have documented the abundant presence of sulphate-rich mineral associations on the surface of Mars. Together with widespread occurrences of silica and frequent enrichments of chlorine and bromine in soils and rocks, the sulphate associations are

  11. Complete sulphate removal from neutralised acidic mine drainage with barium carbonate

    CSIR Research Space (South Africa)

    Swanepoel, H

    2012-03-01

    Full Text Available -barium-calcium) Desalination process which uses barium salts to further reduce the sulphate concentration to acceptable levels with the added advantage that sulphate removal can be controlled due to the low solubility of BaSO4. This paper reports on the results...

  12. Studies on calcium, magnesium and sulphate in the Mandovi and Zuari river system (Goa)

    Digital Repository Service at National Institute of Oceanography (India)

    SenGupta, R.; Naik, S.

    -conservative parameters. Sulphate, however behaves in a purely conservative manner and remains in a steady state in the rivers. A'Simple mixture'relationship is applied to calculate the dilution and mixing processes in the rivers using calcium, magnesium and sulphate...

  13. Glass: a candidate engineered material for management of high level nuclear waste

    International Nuclear Information System (INIS)

    Mishra, R.K.; Kaushik, C.P.

    2011-01-01

    While the commercial importance of glass is generally recognized, a few people are aware of extremely wide range of glass formulations that can be made and of the versatility of this engineered material. Some of the recent developments in the field of glass leading to various technological applications include glass fiber reinforcement of cement to give new building materials, substrates for microelectronics circuitry in form of semiconducting glasses, nuclear waste immobilization and specific medical applications. The present paper covers fundamental understanding of glass structure and its application for immobilization of high level radioactive liquid waste. High level radioactive liquid waste (HLW) arising during reprocessing of spent fuel are immobilized in sodium borosilicate glass matrix developed indigenously. Glass compositions are modified according to the composition of HLW to meet the criteria of desirable properties in terms. These glass matrices have been characterized for different properties like homogeneity, chemical durability, thermal stability and radiation stability. (author)

  14. Spin glasses

    International Nuclear Information System (INIS)

    Mookerjee, Abhijit

    1976-01-01

    ''Spin glasses'', are entire class of magnetic alloys of moderate dilution, in which the magnetic atoms are far enough apart to be unlike the pure metal, but close enough so that the indirect exchange energy between them (mediated by the s-d interaction between local moments and conduction electrons) dominates all other energies. Characteristic critical phenomena displayed such as freezing of spin orientation at 'Tsub(c)' and spreading of magnetic ordering, are pointed out. Anomalous behaviour, associated with these critical phenomena, as reflected in : (i) Moessbauer spectroscopy giving hyperfine splitting at Tsub(c), (ii) maxima in susceptibility and remanent magnetism, (iii) thermopower maxima and change in slope, (iv) Characteristic cusp in susceptibility and its removal by very small magnetic fields, and (v) conductivity-resistivity measurements, are discussed. Theoretical developments aimed at explaining these phenomena, in particular, the ideas from percolation and localisation theories, and the approach based on the gellations of polymers, are discussed. Finally, a new approach based on renormalisation group in disordered systems is also briefly mentioned. (K.B.)

  15. Sulphate, more than a nutrient, protects the microalga Chlamydomonas moewusii from cadmium toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Mera, Roi; Torres, Enrique, E-mail: torres@udc.es; Abalde, Julio

    2014-03-01

    Highlights: • Sulphate effect on cadmium toxicity in the microalga Chlamydomonas moewusii Gerloff. • Cadmium increases the sulphur requirements in Chlamydomonas moewusii. • Kinetic coefficients for sulphate utilization and cadmium effect on them. • Sulphate and cadmium influence on the biosynthesis of low-molecular mass thiols. • Cadmium toxicity reduction by sulphate due to higher biosynthesis of thiols. - Abstract: Sulphur is an essential macroelement that plays important roles in living organisms. The thiol rich sulphur compounds, such as cysteine, γ-Glu–Cys, glutathione and phytochelatins participate in the tolerance mechanisms against cadmium toxicity. Plants, algae, yeasts and most prokaryotes cover their demand for reduced sulphur by reduction of inorganic sulphate. The aim of this study was to investigate, using a bifactorial experimental design, the effect of different sulphate concentrations in the nutrient solution on cadmium toxicity in the freshwater microalga Chlamydomonas moewusii. Cell growth, kinetic parameters of sulphate utilization and intracellular concentrations of low-molecular mass thiol compounds were determined. A mathematical model to describe the growth of this microalga based on the effects of sulphate and cadmium was obtained. An ANOVA revealed an interaction between them, 16% of the effect sizes was explained by this interaction. A higher amount of sulphate in the culture medium allowed a higher cadmium tolerance due to an increase in the thiol compound biosynthesis. The amount of low-molecular mass thiol compounds, mainly phytochelatins, synthesized by this microalga was significantly dependent on the sulphate and cadmium concentrations; the higher phytochelatin content was obtained in cultures with 4 mg Cd/L and 1 mM sulphate. The maximum EC{sub 50} value (based on nominal cadmium concentration) reached for this microalga was 4.46 ± 0.42 mg Cd/L when the sulphate concentration added to the culture medium was also 1 m

  16. Influence of pressure on acoustic and rheologic parameters in water solutions of laury sodium sulfate

    Science.gov (United States)

    Khamidov, B. T.; Lezhnev, N. B.

    1995-10-01

    Ultrasonic velocity and density in water solutions of lauril sodium sulphate at frequency 36 MHz, within the range of pressures from 0.1 to 105 MPa at temperature T equals 293 K were measured. According to data of ultrasonic velocity and density under high pressures there was calculated adiabatic compressibility in objects studied from pressure. It was found out that the region of critical concentration of micelle formation has been shifted to the zone of much more low concentrations.

  17. The effects of large scale processing on caesium leaching from cemented simulant sodium nitrate waste

    International Nuclear Information System (INIS)

    Lee, D.J.; Brown, D.J.

    1982-01-01

    The effects of large scale processing on the properties of cemented simulant sodium nitrate waste have been investigated. Leach tests have been performed on full-size drums, cores and laboratory samples of cement formulations containing Ordinary Portland Cement (OPC), Sulphate Resisting Portland Cement (SRPC) and a blended cement (90% ground granulated blast furnace slag/10% OPC). In addition, development of the cement hydration exotherms with time and the temperature distribution in 220 dm 3 samples have been followed. (author)

  18. Sulphation reactions of oxidic dust particles in waste heat boiler environment. Literature review

    Energy Technology Data Exchange (ETDEWEB)

    Ranki, T.

    1999-09-01

    Sulphation of metal oxides has an important role in many industrial processes. In different applications sulphation reactions have different aims and characteristics. In the flash smelting process sulphation of oxidic flue dust is a spontaneous and inevitable phenomena, which takes place in the waste heat boiler (WHB) when cooling down hot dust laden off-gases from sulphide smelters. Oxidic dust particles (size 0 - 50 {mu}m) react with O{sub 2} and SO{sub 2} or SO{sub 3} in a certain temperature range (500 - 800 deg C). Sulphation reactions are highly exothermic releasing large amount of heat, which affects the gas cooling and thermal performance of the boiler. Thermodynamics and kinetics of the system have to be known to improve the process and WHB operation. The rate of sulphation is affected by the prevailing conditions (temperature, gas composition) and particle size and microstructure (porosity, surface area). Some metal oxides (CuO) can react readily with SO{sub 2} and O{sub 2} and act as self-catalysts, but others (NiO) require the presence of an external catalyst to enhance the SO{sub 3} formation and sulphation to proceed. Some oxides (NiO) sulphate directly, some (CuO) may form first intermediate phases (basic sulphates) depending on the reaction conditions. Thus, the reaction mechanisms are very complex. The aim of this report was to search information about the factors affecting the dust sulphation reactions and suggested reaction mechanisms and kinetics. Many investigators have studied sulphation thermodynamics and reaction kinetics and mechanisms of macroscopical metal oxide pieces, but only few articles have been published about sulphation of microscopical particles, like dust. All the found microscale studies dealt with sulphation reactions of calcium oxide, which is not present in the flash smelting process, but used as an SO{sub 2} absorbent in the combustion processes. However, also these investigations may give some hints about the sulphation

  19. Fluoride removal performance of glass derived hydroxyapatite

    International Nuclear Information System (INIS)

    Liang, Wen; Zhan, Lei; Piao, Longhua; Russel, Christian

    2011-01-01

    Research highlights: → Novel sodium calcium borate glass derived hydroxyapatite (G-HAP) is prepared. → Micro-G-HAP adsorbs F - ions in solutions more effectively than commercial nano-HAP. → The adsorption kinetics and isotherms are well fitted by a second order kinetic model and Freundlich isotherm model. -- Abstract: A novel sodium calcium borate glass derived hydroxyapatite (G-HAP) with different ranges of particle size was prepared by immersion sodium calcium borate glass in 0.1 M K 2 HPO 4 solution by the ratio of 50 g L -1 for 7 days. The unique advantage of G-HAP for the adsorption of fluoride ions in solutions was studied. The effects of size and quantity of particles, pH value and adsorption time on adsorption performance were investigated. The maximum adsorption capacity was 17.34 mg g -1 if 5 g L -1 , - in solution more effectively than commercial nano-HAP, which makes potential application of the G-HAP in removing the fluoride ions from wastewater. The adsorption kinetics and isotherms for F - could be well fitted by a second order kinetic model and Freundlich isotherm model respectively, which could be used to describe the adsorption behavior. The mechanism of G-HAP in immobilizing F - from aqueous solutions was investigated by the X-ray diffraction (XRD), infrared spectra (IR) and scanning electron microscopy (SEM).

  20. Bioactivity and Applications of Sulphated Polysaccharides from Marine Microalgae

    Directory of Open Access Journals (Sweden)

    Rui Manuel Santos Costa de Morais

    2013-01-01

    Full Text Available Marine microalgae have been used for a long time as food for humans, such as Arthrospira (formerly, Spirulina, and for animals in aquaculture. The biomass of these microalgae and the compounds they produce have been shown to possess several biological applications with numerous health benefits. The present review puts up-to-date the research on the biological activities and applications of polysaccharides, active biocompounds synthesized by marine unicellular algae, which are, most of the times, released into the surrounding medium (exo- or extracellular polysaccharides, EPS. It goes through the most studied activities of sulphated polysaccharides (sPS or their derivatives, but also highlights lesser known applications as hypolipidaemic or hypoglycaemic, or as biolubricant agents and drag-reducers. Therefore, the great potentials of sPS from marine microalgae to be used as nutraceuticals, therapeutic agents, cosmetics, or in other areas, such as engineering, are approached in this review.

  1. Identification of nitrates and sulphates with dynamic SIMS

    International Nuclear Information System (INIS)

    Fichtner, M.; Goschnick, J.; Ache, H.J.

    1994-01-01

    Sputter conditions are outlined for the identification of chemically sensitive salt compounds, such as nitrates or sulphates, in multicomponent samples of environmental origin using dynamic SIMS for depth-profiling with nanoscale resolution. Sputtering with 1 keV Xe + has been found to be appropriate to enable both the emission of decisive molecular ions with enough intensity as well as substantial erosion for depth-profiling. The use of heavy projectiles reduces the destruction of chemical compounds in the surface of the solid and enhances sensitivity and identification power of SIMS. The method was applied to the analysis of urban outdoor aerosol particles to investigate the conversion of NaCl into Na 2 SO 4 or NaNO 3 by the interaction of sea salt aerosol with the atmospheric pollutants NO x and SO x . Only NaNO 3 was found in the sea salt fraction. (orig.)

  2. The microbial communities and potential greenhouse gas production in boreal acid sulphate, non-acid sulphate, and reedy sulphidic soils

    Energy Technology Data Exchange (ETDEWEB)

    Šimek, Miloslav, E-mail: misim@upb.cas.cz [Biology Centre AS CR, v. v. i., Institute of Soil Biology, 370 05 České Budějovice (Czech Republic); University of South Bohemia, Faculty of Science, 370 05 České Budějovice (Czech Republic); Virtanen, Seija; Simojoki, Asko [Department of Food and Environmental Sciences, University of Helsinki, FI-00014 Helsinki (Finland); Chroňáková, Alica; Elhottová, Dana; Krištůfek, Václav [Biology Centre AS CR, v. v. i., Institute of Soil Biology, 370 05 České Budějovice (Czech Republic); Yli-Halla, Markku [Department of Food and Environmental Sciences, University of Helsinki, FI-00014 Helsinki (Finland)

    2014-01-01

    Acid sulphate (AS) soils along the Baltic coasts contain significant amounts of organic carbon and nitrogen in their subsoils. The abundance, composition, and activity of microbial communities throughout the AS soil profile were analysed. The data from a drained AS soil were compared with those from a drained non-AS soil and a pristine wetland soil from the same region. Moreover, the potential production of methane, carbon dioxide, and nitrous oxide from the soils was determined under laboratory conditions. Direct microscopic counting, glucose-induced respiration (GIR), whole cell hybridisation, and extended phospholipid fatty acid (PLFA) analysis confirmed the presence of abundant microbial communities in the topsoil and also in the deepest Cg2 horizon of the AS soil. The patterns of microbial counts, biomass and activity in the profile of the AS soil and partly also in the non-AS soil therefore differed from the general tendency of gradual decreases in soil profiles. High respiration in the deepest Cg2 horizon of the AS soil (5.66 μg C g{sup − 1} h{sup − 1}, as compared to 2.71 μg C g{sup − 1} h{sup − 1} in a top Ap horizon) is unusual but reasonable given the large amount of organic carbon in this horizon. Nitrous oxide production peaked in the BCgc horizon of the AS and in the BC horizon of the non-AS soil, but the peak value was ten-fold higher in the AS soil than in the non-AS soil (82.3 vs. 8.6 ng N g{sup − 1}d{sup − 1}). The data suggest that boreal AS soils on the Baltic coast contain high microbial abundance and activity. This, together with the abundant carbon and total and mineral nitrogen in the deep layers of AS soils, may result in substantial gas production. Consequently, high GHG emissions could occur, for example, when the generally high water table is lowered because of arable farming. - Highlights: •Boreal acid sulphate soils contain large amounts of organic C and N in subsoils. •Microbial communities throughout the acid

  3. Sodium Ferric Gluconate Injection

    Science.gov (United States)

    Sodium ferric gluconate injection is used to treat iron-deficiency anemia (a lower than normal number of ... are also receiving the medication epoetin (Epogen, Procrit). Sodium ferric gluconate injection is in a class of ...

  4. Naproxen sodium overdose

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002507.htm Naproxen sodium overdose To use the sharing features on this page, please enable JavaScript. Naproxen sodium is a nonsteroidal anti-inflammatory drug (NSAID) used ...

  5. Sodium hydroxide poisoning

    Science.gov (United States)

    Sodium hydroxide is a very strong chemical. It is also known as lye and caustic soda. This ... poisoning from touching, breathing in (inhaling), or swallowing sodium hydroxide. This article is for information only. Do ...

  6. Sodium pumping: pump problems

    International Nuclear Information System (INIS)

    Guer, M.; Guiton, P.

    Information on sodium pumps for LMFBR type reactors is presented concerning ring pump design, pool reactor pump design, secondary pumps, sodium bearings, swivel joints of the oscillating annulus, and thermal shock loads

  7. Docusate Sodium and Pregnancy

    Science.gov (United States)

    ... a risk of miscarriage. Can use of docusate sodium during pregnancy cause birth defects? Few studies have been done to look at the possible risks of docusate sodium during pregnancy. However, the available studies show that when used ...

  8. Sodium carbonate poisoning

    Science.gov (United States)

    Sodium carbonate (known as washing soda or soda ash) is a chemical found in many household and industrial products. This article focuses on poisoning due to sodium carbonate. This article is for information only. Do NOT ...

  9. ELTA: Citatrademark: Sodium measurement

    International Nuclear Information System (INIS)

    Mauvais, O.

    2002-01-01

    ELTA is pleased to present its last model of Sodium analyzers: CITA 2340: Automatically controlled sodium meter, integrating more automation and performances results respecting costs and wastes reduction. (authors)

  10. Hydrochemistry of rivers in an acid sulphate soil hotspot area in western Finland

    Directory of Open Access Journals (Sweden)

    M. ROOS

    2008-12-01

    Full Text Available During heavy rains and snow melting, acid sulphate (AS soils on the coastal plains of Finland are flushed resulting in discharge of acidic and metal-rich waters that strongly affect small streams. In this study, the impact of AS soils occurrence and hydrological changes on water quality were determined for 21 rivers (catchment sizes between 96–4122 km2 running through an AS soil hotspot area in western central Finland. Water samples, collected at the outlet, during eight selected events, were analysed for pH, dissolved organic carbon, electrical conductivity (EC and 32 chemical elements. Based on the correlation with percentage arable land in the catchments (a rough estimate of AS soil occurrences, as up to 50% of the arable land is underlain with these soils, it was possible to categorize variables into those that are enriched in runoff from such land, depleted in runoff from such land (only one element, and not affected by land-use type in the catchments. Of the variables enriched in runoff from arable land, some were leached from AS soils during high-water flows, in particular (aluminium, boron, beryllium, cadmium, cobalt, copper, lithium, manganese, nickel, sulphur, silicon, thorium, thallium, uranium, and zinc and others occurred in highest concentrations during lower flows (calcium, EC, potassium, magnesium, sodium, rubidium and strontium. Molybdenum and phosphorus were not leached from AS soils in larger amounts than from other soils and thus related to other factors connected to the arable land. Based on the concentrations of potentially toxic metals derived from AS soils, the 21 rivers were ranked from the least (Lestijoki River, Lapväärtinjoki River and Perhonjoki River to the most (Sulvanjoki River, Vöyrinjoki River and Maalahdenjoki River heavily AS soil impacted. It has been decided that Vöyrinjoki is to be dredged along a ca. 20 km distance. This is quite alarming considering the high metal concentrations in the river.;

  11. Liquid sodium technology research

    International Nuclear Information System (INIS)

    Kim, W.C.; Lee, Y.W.; Nam, H.Y.; Chun, S.Y.; Kim, J.; Won, S.Y.

    1982-01-01

    This report describes the technology of impurity control and measurement of liquid sodium, problems associated with material degradation and change of heat transfer characteristics in liquid sodium, and the conceptual design of multipurpose sodium test loop. Discussion and the subsequent analysis are also made with regard to the test results for the sodium-H 2 0 reaction and its effects on the system. (author)

  12. 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

  13. Demonstration of sulfur solubility determinations in high waste loading, low-activity waste glasses

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-04-25

    A method recommended by Pacific Northwest National Laboratory (PNNL) for sulfate solubility determinations in simulated low-activity waste glasses was demonstrated using three compositions from a recent Hanford high waste loading glass study. Sodium and sulfate concentrations in the glasses increased after each re-melting step. Visual observations of the glasses during the re-melting process reflected the changes in composition. The measured compositions showed that the glasses met the targeted values. The amount of SO3 retained in the glasses after washing was relatively high, ranging from 1.6 to 2.6 weight percent (wt %). Measured SnO2 concentrations were notably low in all of the study glasses. The composition of the wash solutions should be measured in future work to determine whether SnO2 is present with the excess sulfate washed from the glass. Increases in batch size and the amount of sodium sulfate added did not have a measureable impact on the amount of sulfate retained in the glass, although this was tested for only a single glass composition. A batch size of 250 g and a sodium sulfate addition targeting 7 wt %, as recommended by PNNL, will be used in future experiments.

  14. Glass material oxidation and dissolution system: Converting miscellaneous fissile materials to glass

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Ferrada, J.J.

    1996-01-01

    The cold war and the development of nuclear energy have resulted in significant inventories of miscellaneous fissile materials (MFMs). MFMs include (1) plutonium scrap and residue, (2) miscellaneous spent nuclear fuel (SNF), (3) certain hot cell wastes, and (4) many one-of-a-kind materials. Major concerns associated with the long-term management of these materials include: safeguards and nonproliferation issues; health, environment, and safety concerns. waste management requirements; and high storage costs. These issues can be addressed by converting the MFMs to glass for secure, long-term storage or repository disposal; however, conventional glass-making processes require oxide-like feed materials. Converting MFMs to oxide-like materials with subsequent vitrification is a complex and expensive process. A new vitrification process has been invented, the Glass Material Oxidation and Dissolution System (GMODS), which 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 (NaCl) stream. Laboratory work has demonstrated the conversion of cerium (a plutonium surrogate), uranium, Zircaloy, stainless steel, multiple oxides, and other materials to glass. However, significant work is required to develop GMODS further for applications at an industrial scale. If implemented, GMODS will provide a new approach to manage these materials

  15. Study on Modified Water Glass Used in High Temperature Protective Glass Coating for Ti-6Al-4V Titanium Alloy

    Directory of Open Access Journals (Sweden)

    Shuang Yang

    2018-04-01

    Full Text Available Sodium silicate water glass was modified with sodium polyacrylate as the binder, the composite slurry used for high-temperature oxidation-resistant coating was prepared by mixing glass powder with good lubrication properties in the binder. The properties of the modified binder and high-temperature oxidation resistance of Ti-6Al-4V titanium alloy coated with composite glass coating were studied by XRD, SEM, EDS, TG-DSC and so on. Results showed that sodium polyacrylate modified water glass could obviously improve the suspension stability of the binder, the pyrolytic carbon in the binder at high temperature could increase the surface tension in the molten glass system, and the composite glass coating could be smooth and dense after heating. Pyrolytic carbon diffused and combined with oxygen in the coating under the heating process to protect the titanium alloy from oxidation. The thickness of the oxide layer was reduced 51% after applying the high-temperature oxidation-resistant coating. The coating also showed a nearly 30% reduction in friction coefficient due to the boundary lubricant regime. During cooling, the coating could be peeled off easily because of the mismatched CTE between the coating and substrate.

  16. Sodium sieving in children

    NARCIS (Netherlands)

    Rusthoven, Esther; Krediet, Raymond T.; Willems, Hans L.; Monnens, Leo A.; Schröder, Cornelis H.

    2005-01-01

    Sodium sieving is a consequence of dissociation between the amount of water and sodium transported over the peritoneal membrane. This dissociation occurs in the presence of aquaporin-mediated water transport. Sieving of sodium can be used as a rough measure for aquaporin-mediated water transport.

  17. Phase separation of cesium from lead borosilicate glass by heat treatment under a reducing atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhanglian; Okada, Takashi, E-mail: t-okada@u-fukui.ac.jp; Nishimura, Fumihiro; Yonezawa, Susumu

    2016-11-05

    Highlights: • Cesium was phase separated from lead borosilicate glass under a reductive atmosphere. • The phase separation occurred on the glass surface that was in contact with the gas. • The leachability of cesium was enhanced by the phase separation. • The degree of such enhancement varied depending on the heat treatment conditions. - Abstract: A phase-separation technique for removing sodium from glass using a heat-treatment method under a reducing atmosphere was previously developed for sodium recovery from waste glass. In this study, this technique was applied to cesium-containing lead borosilicate glass to concentrate the cesium in phase-separated sodium-rich materials for efficient cesium extraction. The theoretical phase-separation temperature of the sodium-rich phase was simulated by thermodynamic equilibrium calculations and was predicted to occur below 700 °C for lead borosilicate glass. Experimentally, a simulated lead borosilicate glass was melted at 1000 °C and subsequently annealed below 700 °C under a CO-containing reducing atmosphere. The phase separation of cesium was found to occur with sodium enrichment on the glass surface that was in contact with the gas phase, promoting cesium extraction from the treated glass using water. The cesium extraction efficiency was affected by the surface area of the treated glass that was in contact with water, and under the examined conditions, the cesium extraction efficiency was up to 66%. Phase separation using reductive heat treatment, combined with a water leaching technique, is suggested to be effective for extracting cesium incorporated in borosilicate glass waste.

  18. Oxygen isotopic composition of sulphates from some mineral waters and mine waters in western Bohemia

    International Nuclear Information System (INIS)

    Smejkal, V.

    1979-01-01

    Two main genetic types of sulphate can be distinguished according to the delta 18 O(SO 4 2- ) measurements in sulphate-rich mineral and mine waters of western Bohemia - sulphates in descending mine waters and in weathered outcrops of graphitic pyrite slates from areas outside Tertiary basins, which originated in recent time by the oxidation of sulphides in the presence of atmospheric oxygen, have delta 18 O values from -2.1 to -6.1 per mille SMOW; and sulphates from springs of mineral waters of the renowned spas of Karlovy Vary, Frantiskovy Lazne and Marianske Lazne show distinctly heavier delta 18 O values - from +4.0 to +6.4 per mille, with maximum of values between +5.0 and +6.0 per mille. Similar delta 18 O values have been established in thenardites and in gypsum in Miocene claystones and in sulphates of some mine waters in the nearby Tertiary Cheb and Sokolov Basins. The presented results indicate that sulphates in mineral waters of the Karlovy Vary type originate mainly by leaching of Miocene sulphates and not by present-day oxidation of sulphidic sulphur. (author)

  19. Composition-Structure-Property Relationships in Boroaluminosilicate Glasses

    DEFF Research Database (Denmark)

    Zheng, Qiuju; Potuzak, M.; Mauro, J.C.

    2012-01-01

    boroaluminosilicate glasses from peralkaline to peraluminous compositions by substituting Al2O3 for SiO2. Our results reveal a pronounced change in all the measured physical properties (density, elastic moduli, hardness, glass transition temperature, and liquid fragility) around [Al2O3]–[Na2O]=0. The structural......The complicated structural speciation in boroaluminosilicate glasses leads to a mixed network former effect yielding nonlinear variation in many macroscopic properties as a function of chemical composition. Here we study the composition–structure–property relationships in a series of sodium...

  20. lead glass brick

    CERN Multimedia

    When you look through the glass at a picture behind, the picture appears raised up because light is slowed down in the dense glass. It is this density (4.06 gcm-3) that makes lead glass attractive to physicists. The refractive index of the glass is 1.708 at 400nm (violet light), meaning that light travels in the glass at about 58% its normal speed. At CERN, the OPAL detector uses some 12000 blocks of glass like this to measure particle energies.

  1. Pressure-Induced Changes in Inter-Diffusivity and Compressive Stress in Chemically Strengthened Glass

    DEFF Research Database (Denmark)

    Svenson, Mouritz Nolsøe; Thirion, Lynn M.; Youngman, Randall E.

    chamber to compress bulk glass samples isostatically up to 1 GPa at elevated temperature before or after the ion exchange treatment of an industrial sodium-magnesium aluminosilicate glass. Compression of the samples prior to ion exchange leads to a decreased Na+-K+ inter-diffusivity, increased compressive...

  2. Report of sodium cavitation

    International Nuclear Information System (INIS)

    Murai, Hitoshi; Shima, Akira; Oba, Toshisaburo; Kobayashi, Ryoji; Hashimoto, Hiroyuki

    1975-01-01

    The damage of components for LMFBRs due to sodium cavitation is serious problem. This report summarizes the following items, (1) mechanism of the incipience of sodium cavitation, (2) damage due to sodium cavitation, (3) detection method for sodium cavitation, and (4) estimation method for sodium cavitation by the comparison with water cavitation. Materials were collected from the reports on liquid metal cavitation, sodium cavitation and water cavitation published from 1965 to now. The mechanism of the incipience of sodium cavitation cavitation parameters (mean location, distributed amount or occurrence aspect and stability), experiment of causing cavitation with Venturi tube, and growth of bubbles within superheated sodium. The sodium cavitation damage was caused by magnetostriction vibration method and with Venturi tube. The state of damage was investigated with the cavitation performance of a sodium pump, and the damage was examined in view of the safety of LMFBR plants. Sodium cavitation was detected with acoustic method, radiation method, and electric method. The effect of physical property of liquid on incipient cavitation was studied. These are thermodynamic effect based on quasistatic thermal equilibrium condition and the effect of the physical property of liquid based on bubble dynamics. (Iwase, T.)

  3. Sodium safety manual

    International Nuclear Information System (INIS)

    Hayes, D.J.; Gardiner, R.L.

    1980-09-01

    The sodium safety manual is based upon more than a decade of experience with liquid sodium at Berkeley Nuclear Laboratories (BNL). It draws particularly from the expertise and experience developed in the course of research work into sodium fires and sodium water reactions. It draws also on information obtained from the UKAEA and other sodium users. Many of the broad principles will apply to other Establishments but much of the detail is specific to BNL and as a consequence its application at other sites may well be limited. Accidents with sodium are at best unpleasant and at worst lethal in an extremely painful way. The object of this manual is to help prevent sodium accidents. It is not intended to give detailed advice on specific precautions for particular situations, but rather to set out the overall strategy which will ensure that sodium activities will be pursued safely. More detail is generally conveyed to staff by the use of local instructions known as Sodium Working Procedures (SWP's) which are not reproduced in this manual although a list of current SWP's is included. Much attention is properly given to the safe design and operation of larger facilities; nevertheless evidence suggests that sodium accidents most frequently occur in small-scale work particularly in operations associated with sodium cleaning and special care is needed in all such cases. (U.K.)

  4. Automatic colorimetric determination of low concentrations of sulphate for measuring sulphur dioxide in ambient air

    Energy Technology Data Exchange (ETDEWEB)

    Persson, G A

    1966-01-01

    An automatic colorimetric method for the determination of low concentrations of sulphate (0-10 microgram/ml) using the thoron indicator is described. Total amounts of sulphate as small as 0.3 micrograms can be determined. The sulphate is precipitated with barium perchlorate and the excess of barium is indicated with 1-(o-arsenophenylazo)-2-naphthol-3-6-disulfonic acid(thoron). The procedure is worked out primarily for the determination of sulphur dioxide in air after absorption in diluted hydrogen peroxide.

  5. Tyrosine sulphation is not required for microvillar expression of intestinal aminopeptidase N

    DEFF Research Database (Denmark)

    Danielsen, E M

    1988-01-01

    incorporation of [35S]sulphate into aminopeptidase N and other major microvillar hydrolases by 70-85% compared with controls, indicating an inhibition of their post-translational tyrosine sulphation. In labelling experiments with [35S]methionine from 0.5 to 5 h, DCNP was tested for its possible influence...... on synthesis, processing and microvillar expression of aminopeptidase N, but no effect on any of these parameters could be detected. It can therefore be concluded that tyrosine sulphation is not required (for instance as a sorting signal) for the targeting of newly synthesized enzymes to the microvillar...

  6. Revealing the fast atomic motion of network glasses.

    Science.gov (United States)

    Ruta, B; Baldi, G; Chushkin, Y; Rufflé, B; Cristofolini, L; Fontana, A; Zanatta, M; Nazzani, F

    2014-05-19

    Still very little is known on the relaxation dynamics of glasses at the microscopic level due to the lack of experiments and theories. It is commonly believed that glasses are in a dynamical arrested state, with relaxation times too large to be observed on human time scales. Here we provide the experimental evidence that glasses display fast atomic rearrangements within a few minutes, even in the deep glassy state. Following the evolution of the structural relaxation in a sodium silicate glass, we find that this fast dynamics is accompanied by the absence of any detectable aging, suggesting a decoupling of the relaxation time and the viscosity in the glass. The relaxation time is strongly affected by the network structure with a marked increase at the mesoscopic scale associated with the ion-conducting pathways. Our results modify the conception of the glassy state and asks for a new microscopic theory.

  7. Migration behaviour of Pu released from Pu-doped glass in compacted bentonite

    International Nuclear Information System (INIS)

    Ashida, T.; Kohara, Y.; Yui, M.

    1994-01-01

    In order to investigate the coupled behavior of Pu release from the waste glass and transport in bentonite, a migration experiment with compacted sodium-type bentonite saturated with distilled water was carried out at room temperature, in which Pu-doped borosilicate glass was sandwiched. Under these conditions, leaching of Pu from the glass, diffusion and sorption of Pu in the compacted bentonite occur simultaneously. (orig.)

  8. Identification of glass compositions suitable for disposal of waste reactive metal

    International Nuclear Information System (INIS)

    Varma, R.; Brown, A.P.; Kumar, R.; San-Pedro, R.; Freeman, C.J.; Helt, J.E.

    1988-09-01

    This study was conducted in support of a project to convert waste sodium to a form that is amenable to easy disposal in ordinary landfills. This waste sodium will be from reactor and other operations at the US Department of Energy and will contain small amounts of radioactive species that must not be released to the environment in an uncontrolled manner. The sodium will be converted into a glass that will contain and isolate the radionuclides present in it. This study was conducted to define acceptable glass compositions that (1) are resistant to leaching of sodium by groundwater and rainwater, (2) contain a relatively large proportion of sodium so that unreasonably large volumes of the glass for disposal will not be produced, and (3) are conveniently prepared from the waste sodium. For this purpose, glass samples containing varying amounts of the oxides of sodium, calcium, boron, aluminum, and silicon were prepared in the laboratory. The samples were subjected to the accelerated MCC-1 test to determine resistance to leaching by water at 60/degree/C. Soda-silica glasses were observed to dissolve in the water rather quickly. Addition of the other ingredients was found to impart significant leach resistance to the glasses. Among the high-Na 2 O glasses, those containing alumina (3% Al 2 O 3 -10% CaO-30% Na 2 O and 6% Al 2 O 3 -10% B 2 O 3 -30% Na 2 O) were found to be most resistant to leaching. Lowering the Na 2 O content to 20% made these glasses even more leach resistant. 8 refs., 6 figs., 2 tabs

  9. Glass and nuclear wastes

    International Nuclear Information System (INIS)

    Sombret, C.

    1982-10-01

    Glass shows interesting technical and economical properties for long term storage of solidified radioactive wastes by vitrification or embedding. Glass composition, vitrification processes, stability under irradiation, thermal stability and aqueous corrosion are studied [fr

  10. Microstructuring of glasses

    CERN Document Server

    Hülsenberg, Dagmar; Bismarck, Alexander

    2008-01-01

    As microstructured glass becomes increasingly important for microsystems technology, the main application fields include micro-fluidic systems, micro-analysis systems, sensors, micro-actuators and implants. And, because glass has quite distinct properties from silicon, PMMA and metals, applications exist where only glass devices meet the requirements. The main advantages of glass derive from its amorphous nature, the precondition for its - theoretically - direction-independent geometric structurability. Microstructuring of Glasses deals with the amorphous state, various glass compositions and their properties, the interactions between glasses and the electromagnetic waves used to modify it. Also treated in detail are methods for influencing the geometrical microstructure of glasses by mechanical, chemical, thermal, optical, and electrical treatment, and the methods and equipment required to produce actual microdevices.

  11. Detecting the global and regional effects of sulphate aerosol geoengineering

    Science.gov (United States)

    Lo, Eunice; Charlton-Perez, Andrew; Highwood, Ellie

    2017-04-01

    Climate warming is unequivocal. In addition to carbon dioxide emission mitigation, some geoengineering ideas have been proposed to reduce future surface temperature rise. One of these proposals involves injecting sulphate aerosols into the stratosphere to increase the planet's albedo. Monitoring the effectiveness of sulphate aerosol injection (SAI) would require us to be able to distinguish and detect its cooling effect from the climate system's internal variability and other externally forced temperature changes. This research uses optimal fingerprinting techniques together with simulations from the GeoMIP data base to estimate the number of years of observations that would be needed to detect SAI's cooling signal in near-surface air temperature, should 5 Tg of sulphur dioxide be injected into the stratosphere per year on top of RCP4.5 from 2020-2070. The first part of the research compares the application of two detection methods that have different null hypotheses to SAI detection in global mean near-surface temperature. The first method assumes climate noise to be dominated by unforced climate variability and attempts to detect the SAI cooling signal and greenhouse gas driven warming signal in the "observations" simultaneously against this noise. The second method considers greenhouse gas driven warming to be a non-stationary background climate and attempts to detect the net cooling effect of SAI against this background. Results from this part of the research show that the conventional multi-variate detection method that has been extensively used to attribute climate warming to anthropogenic sources could also be applied for geoengineering detection. The second part of the research investigates detection of geoengineering effects on the regional scale. The globe is divided into various sub-continental scale regions and the cooling effect of SAI is looked for in the temperature time series in each of these regions using total least squares multi

  12. The investigation of deactivation the tailings from sulphate uranium technology

    International Nuclear Information System (INIS)

    Nikonov, V.I.; Knjazev, O.I.; Ruzin, L.I.; Smolnya, T.A.

    2001-01-01

    The purpose of investigation is to decrease contamination of the environment from wastes, produced on treatment of uranium ores by traditional sulphate uranium technology. In the result of treatment the sulphate uranium leaching cakes by 1-3 M chloride or nitrate of alkali-earth metals solutions, the content of radium decrease till (2.4 - 3.0) x 10 -8 Ci/kg. Produced deactivating solutions in which the content of radium-226 and other natural radionuclides exceeds of ten times the limit of tolerance safe concentrations for water (5.4 x 10 -11 Ci/l Ra-226) further may be treated by sorption or extraction. Due to the reason we pay our attention to the class of non-traditional ion-exchangers, which is the micellar wastes from production of antibiotics (MPW). The problems of it's utilization is very acute. MPW from antibiotics generates everyday is amount of tens tones (on dried mass), contents till 80% of moisture and include in solid phase 50 - 95 % organics in the work we used MPW from erythromycin in form of dried powder with size of particles to 0.05 - 0.16 mm. The possibility of radionuclides extraction by mixture of D2EHPA with TBP or TOPO for nitric deactivated solutions are investigated. It was received the complete extraction Th-230 into organic phase and next concentration with high content of isotope Th-230. Ra-D and Po are not recovered by the extractant. Using the extractant preliminary saturated with barium permit to extract completely Ra from solution. The method purification of technological solutions from activity with using solid extractants - TVEKS was developed. The TVEKS samples on styren-divinylbenzen copolymer base with size 1.0 - 1.5 mm were synthesized. The solid carrier was impregnated by D2EHPA or PN-1200 extractant solution in kerosene and used for extraction of radioactive elements (mainly Ra) from chloride acid solutions with summary activity 8.7 x 10 -10 Ci/l. TVEKS was activated by barium to capacity 1-3 mg/l for increasing purification

  13. Sulphate-reducing bacteria associated with biocorrosion: a review

    Directory of Open Access Journals (Sweden)

    Tania C. de Araujo-Jorge

    1992-09-01

    Full Text Available Biocorrosion means any process of corrosion in wich microorganisms are somehow involved. As far as the petroleum industry is concerned, the anaerobic type is the more important, with Sulphate-Reducing Bacteria (SRB accouting for half of the described processes. SRB are obligate anaerobs that use sulphur, sulphate or other oxidized sulphur compounds as oxidizing agents when decomposing organic material. A typical product of SRB metabolism, hydrogen sulphide -H2S-, is extremely toxic. In the present work we review the literature on mechanisms underlying biocorrosive process in wich SRB are involved and summarize some of the ultrastructural and eletrochemical work developed using SRB obtained from water injection flow in wells located on PETROBRAS offshore marine plataforms, sampled directly in the field over metallic probes, or cultured under laboratory conditions. Biofilms develop when SRB adhere to inert surfaces. A high diversity of morphological types is found inside these biofilms. Their extracellular matrix is highly hydrated and mainly anionic, as shown by its avid reaction with cationic compounds like ruthenium red. We have noted that variations in iron contet lead to interesting changes in the ultrastructure of the bacterial cell coat and also in the rate of corrosion induced in metallic test cupons. Since routine methods to prevent and treat SRB contamination and biodeterioration involve the use of biocides that are toxic and always have some environmental impact, an accurate diagnosis of biocorrosion is always required prior to a treatment decision. We developed a method that detects and semi-quantifies the presence of living or dead SRB by using free silver potentials as an indicator of corrosive action by SRB-associated sulphides. We found a correlation between sulphide levels (determined either by spectrophotometry, or using a silver electrode -E(Ag- that measured changes in free potentials induced by the presence of exogeneously

  14. Dialysate sodium and sodium gradient in maintenance hemodialysis: a neglected sodium restriction approach?

    OpenAIRE

    Munoz Mendoza, Jair; Sun, Sumi; Chertow, Glenn M.; Moran, John; Doss, Sheila; Schiller, Brigitte

    2011-01-01

    Background. A higher sodium gradient (dialysate sodium minus pre-dialysis plasma sodium) during hemodialysis (HD) has been associated with sodium loading; however, its role is not well studied. We hypothesized that a sodium dialysate prescription resulting in a higher sodium gradient is associated with increases in interdialytic weight gain (IDWG), blood pressure (BP) and thirst.

  15. Gamma radiation induced changes in nuclear waste glass containing Eu

    Science.gov (United States)

    Mohapatra, M.; Kadam, R. M.; Mishra, R. K.; Kaushik, C. P.; Tomar, B. S.; Godbole, S. V.

    2011-10-01

    Gamma radiation induced changes were investigated in sodium-barium borosilicate glasses containing Eu. The glass composition was similar to that of nuclear waste glasses used for vitrifying Trombay research reactor nuclear waste at Bhabha Atomic Research Centre, India. Photoluminescence (PL) and electron paramagnetic resonance (EPR) techniques were used to study the speciation of the rare earth (RE) ion in the matrix before and after gamma irradiation. Judd-Ofelt ( J- O) analyses of the emission spectra were done before and after irradiation. The spin counting technique was employed to quantify the number of defect centres formed in the glass at the highest gamma dose studied. PL data suggested the stabilisation of the trivalent RE ion in the borosilicate glass matrix both before and after irradiation. It was also observed that, the RE ion distributes itself in two different environments in the irradiated glass. From the EPR data it was observed that, boron oxygen hole centre based radicals are the predominant defect centres produced in the glass after irradiation along with small amount of E’ centres. From the spin counting studies the concentration of defect centres in the glass was calculated to be 350 ppm at 900 kGy. This indicated the fact that bulk of the glass remained unaffected after gamma irradiation up to 900 kGy.

  16. Measurement of optical glasses

    International Nuclear Information System (INIS)

    Nicolau-Rebigan, S.

    1978-11-01

    The possibilities of measurement of the optical glasses parameters needed in building optical devices especially in lasers devices are presented. In the first chapter the general features of the main optical glasses as well as the modalities of obtaining them are given. Chapter two defines the optical glass parameters, and the third chapter describes the measuring methods of the optical glass parameters. Finally, the conclusions which point out the utilization of this paper are presented. (author)

  17. 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

  18. Mechanically reinforced glass beams

    DEFF Research Database (Denmark)

    Nielsen, Jens Henrik; Olesen, John Forbes

    2007-01-01

    laminated float glass beam is constructed and tested in four-point bending. The beam consist of 4 layers of glass laminated together with a slack steel band glued onto the bottom face of the beam. The glass parts of the tested beams are \\SI{1700}{mm} long and \\SI{100}{mm} high, and the total width of one...

  19. Sealing glasses for titanium and titanium alloys

    Science.gov (United States)

    Brow, Richard K.; McCollister, Howard L.; Phifer, Carol C.; Day, Delbert E.

    1997-01-01

    Barium lanthanoborate sealing-glass compositions are provided comprising various combinations (in terms of mole-%) of boron oxide (B.sub.2 O.sub.3), barium oxide (BaO), lanthanum oxide (La.sub.2 O.sub.3), and at least one other oxide selected from the group consisting of aluminum oxide (Al.sub.2 O.sub.3), calcium oxide (CaO), lithium oxide (Li.sub.2 O), sodium oxide (Na.sub.2 O), silicon dioxide (SiO.sub.2), or titanium dioxide (TiO.sub.2). These sealing-glass compositions are useful for forming hermetic glass-to-metal seals with titanium and titanium alloys having an improved aqueous durability and favorable sealing characteristics. Examples of the sealing-glass compositions are provided having coefficients of thermal expansion about that of titanium or titanium alloys, and with sealing temperatures less than about 900.degree. C., and generally about 700.degree.-800.degree. C. The barium lanthanoborate sealing-glass compositions are useful for components and devices requiring prolonged exposure to moisture or water, and for implanted biomedical devices (e.g. batteries, pacemakers, defibrillators, pumps).

  20. Role of SrO on the bioactivity behavior of some ternary borate glasses and their glass ceramic derivatives

    Science.gov (United States)

    Abdelghany, A. M.; Ouis, M. A.; Azooz, M. A.; ElBatal, H. A.; El-Bassyouni, G. T.

    2016-01-01

    Borate glasses containing SrO substituting both CaO and NaO were prepared and characterized for their bioactivity or bone bonding ability. Glass ceramic derivatives were prepared by thermal heat treatment process. FTIR, XRD and SEM measurements for the prepared glass and glass-ceramics before and after immersion in sodium phosphate solution for one and two weeks were carried out. The appearance of two IR peaks within the range 550-680 cm-1 after immersion in phosphate solution indicates the formation of hydroxyapatite or equivalent Sr phosphate layer. X-ray diffraction data agree with the FTIR spectral analysis. The solubility test was carried out for both glasses and glass ceramics derivatives in the same phosphate solution. The introduction of SrO increases the solubility for both glasses and glass ceramics and this is assumed to be due to the formation of Sr phosphate which is more soluble than calcium phosphate (hydroxyapatite). SEM images reveal varying changes in the surfaces of glass ceramics after immersion according to the SrO content.

  1. Role of SrO on the bioactivity behavior of some ternary borate glasses and their glass ceramic derivatives.

    Science.gov (United States)

    Abdelghany, A M; Ouis, M A; Azooz, M A; ElBatal, H A; El-Bassyouni, G T

    2016-01-05

    Borate glasses containing SrO substituting both CaO and NaO were prepared and characterized for their bioactivity or bone bonding ability. Glass ceramic derivatives were prepared by thermal heat treatment process. FTIR, XRD and SEM measurements for the prepared glass and glass-ceramics before and after immersion in sodium phosphate solution for one and two weeks were carried out. The appearance of two IR peaks within the range 550-680cm(-1) after immersion in phosphate solution indicates the formation of hydroxyapatite or equivalent Sr phosphate layer. X-ray diffraction data agree with the FTIR spectral analysis. The solubility test was carried out for both glasses and glass ceramics derivatives in the same phosphate solution. The introduction of SrO increases the solubility for both glasses and glass ceramics and this is assumed to be due to the formation of Sr phosphate which is more soluble than calcium phosphate (hydroxyapatite). SEM images reveal varying changes in the surfaces of glass ceramics after immersion according to the SrO content. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Bio-corrosion of water pipeline by sulphate-reducing bacteria in a ...

    African Journals Online (AJOL)

    esiri

    2013-11-13

    Nov 13, 2013 ... Key words: Sulphate-reducing bacteria, corrosion, water pipeline, biocide. INTRODUCTION ... small amount of organic material required to produce biomass):. )1(. 3. 2 .... Oil, gas and shipping industries are seriously affected.

  3. Measurement of dynamic wedge angles and beam profiles by means of MRI ferrous sulphate gel dosimetry

    Science.gov (United States)

    Bengtsson, Magnus; Furre, Torbjørn; Rødal, Jan; Skretting, Arne; Olsen, Dag R.

    1996-02-01

    The purpose of this study is to examine the possible value of measuring the dose distribution in dynamic wedge photon beams using ferrous sulphate gel phantoms analysed by MRI. The wedge angles and dose profiles were measured for a field size of and for dynamic wedge angles of , , and using a 15 MV photon beam generated from a Clinac 2100 CD (Varian). The dose profiles obtained from MRI ferrous sulphate gel were in good agreement with the dose measurements performed with a diode detector array. Also, the wedge angles determined from the MRI ferrous sulphate gel agreed well with the values obtained by using film dosimetry and with calculations by use of TMS (treatment planning system) (Helax, Uppsala, Sweden). The study demonstrated that MRI ferrous sulphate gel dosimetry is an adequate tool for measurements of some beam characteristics of dynamic radiation fields.

  4. The Metal And Sulphate Removal From Mine Drainage Waters By Biological-Chemical Ways

    Directory of Open Access Journals (Sweden)

    Jenčárová Jana

    2015-06-01

    Full Text Available Mine drainage waters are often characterized by high concentrations of sulphates and metals as a consequence of the mining industry of sulphide minerals. The aims of this work are to prove some biological-chemical processes utilization for the mine drainage water treatment. The studied principles of contamination elimination from these waters include sulphate reduction and metal bioprecipitation by the application of sulphate-reducing bacteria (SRB. Other studied process was metal sorption by prepared biogenic sorbent. Mine drainage waters from Slovak localities Banská Štiavnica and Smolník were used to the pollution removal examination. In Banská Štiavnica water, sulphates decreased below the legislative limit. The elimination of zinc by sorption experiments achieved 84 % and 65 %, respectively.

  5. Particle engineering using sonocrystallization: salbutamol sulphate for pulmonary delivery.

    Science.gov (United States)

    Dhumal, Ravindra S; Biradar, Shailesh V; Paradkar, Anant R; York, Peter

    2009-02-23

    The aim of present work was to produce fine elongated crystals of salbutamol sulphate (SS) by sonocrystallization for pulmonary delivery and compare with micronized and spray dried SS (SDSS) for in vitro aerosolization behavior. Application of ultrasound during anti-solvent crystallization resulted in fine elongated crystals (sonocrystallized SS; SCSS) compared to aggregates of large irregular crystals obtained without sonication. Higher sonication amplitude, time, concentration and lower processing temperatures favored formation of smaller crystals with narrow particle size distribution (PSD). SCSS was separated from dispersion by spray drying in the form of loose aggregates (SD-SCSS). The fine particle fraction (FPF) of formulations with coarse lactose carrier in cascade impactor increased from 16.66% for micronized SS to 31.12% for SDSS (obtained by spray drying aqueous SS solution) and 44.21% for SD-SCSS, due to reduced cohesive/adhesive forces and aerodynamic size by virtue of elongated shape of crystals. SD-SCSS was stable without any change in crystallinity and aerodynamic behavior for 3 months at 40 degrees C/75% RH, but amorphous SDSS showed recrystallization with poor aerosolization performance on storage. Sonocrystallization, a rapid and simple technique is reported for production of SS crystals suitable for inhalation delivery.

  6. Absorption of ammonium sulphate 15N by coffee plants

    International Nuclear Information System (INIS)

    Fenilli, Tatiele Anete Bergamo; Reichardt, Klaus; Bacchi, Osny Oliveira Santos; Trivelin, Paulo Cesar Ocheuze; Dourado Neto, Durval

    2005-01-01

    The objective of this study was to quantify the absorption of ammonium sulphate 15 N by coffee plants. Treatments consisted of five sub-plots of 9 plants, of which the three central ones received 280 kg ha -1 of 15 N, applied at four times: 1/4 on 01 Set 03; 1/4 on 03 Nov 03; 1/4 on 15 Dec 03 and 1/4 on 30 Jan 04. The isotopic enrichment was 2,072 ± 0,001 atom % 15 N. The dry matter of the shoot was evaluated every 60 days, using one plant per replicate, collected outside the sub-plot. They were as similar as possible to the labeled plants, which were used only for isotopic and Total N analysis, after being dried at 65 deg C until constant weight. At harvest, plants had absorbed 42,88% of the fertilizer N. Leaves accumulated the largest amount of fertilizer N, and were also the compartments that received most N from other parts of the plant. The following partition of the fertilizer N was found at harvest: 23.01% in young leaves, 6.23% in old leaves, 4,46% in stem, 3.46% in fruits, 3.10% in young branches and 2.63% in old branches. (author)

  7. Chitosan microparticles for sustaining the topical delivery of minoxidil sulphate.

    Science.gov (United States)

    Gelfuso, Guilherme Martins; Gratieri, Taís; Simão, Patrícia Sper; de Freitas, Luís Alexandre Pedro; Lopez, Renata Fonseca Vianna

    2011-01-01

    Given the hypothesis that microparticles can penetrate the skin barrier along the transfollicular route, this work aimed to obtain and characterise chitosan microparticles loaded with minoxidil sulphate (MXS) and to study their ability to sustain the release of the drug, attempting a further application utilising them in a targeted delivery system for the topical treatment of alopecia. Chitosan microparticles, containing different proportions of MXS/polymer, were prepared by spray drying and were characterised by yield, encapsulation efficiency, size and morphology. Microparticles selected for further studies showed high encapsulation efficiency (∼82%), a mean diameter of 3.0 µm and a spherical morphology without porosities. When suspended in an ethanol/water solution, chitosan microparticles underwent instantaneous swelling, increasing their mean diameter by 90%. Release studies revealed that the chitosan microparticles were able to sustain about three times the release rate of MXS. This feature, combined with suitable size, confers to these microparticles the potential to target and improve topical therapy of alopecia with minoxidil.

  8. Chondroitin sulphate-guided construction of polypyrrole nanoarchitectures

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Zhengnan [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Zhu, Wenjun [Department of Prosthodontics, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Liao, Jingwen [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Huang, Shishu [State Key Laboratory of Oral Diseases, West China College of Stomatology, Sichuan University (China); Department of Orthopaedics and Traumatology, The University of Hong Kong (China); Chen, Junqi; He, Tianrui [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Tan, Guoxin, E-mail: tanguoxin@126.com [Faculty of Light and Chemical, Guangdong University of Technology, Guangzhou 510006 (China); Ning, Chengyun, E-mail: imcyning@scut.edu.cn [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China)

    2015-03-01

    Nanospheres, nanocones, and nanowires are three typical polypyrrole (PPy) nanoarchitectures and electrochemically polymerized with the dope of chondroitin sulphate (CS) in this study. CS, a functional biomacromolecule, guides the formation of PPy nanoarchitectures as the dopant and morphology-directing agent. Combined with our previous reported other PPy nanoarchitectures (such as nanotube arrays and nanowires), this work further proposed the novel mechanism of the construction of PPy/CS nanoarchitectures with the synergistic effect of CS molecular chains structure and the steric hindrance. Compared to the undoped PPy, MC3T3-E1 cells with PPy/CS nanoarchitectures possessed stronger proliferation and osteogenic differentiation capability. This suggests that PPy/CS nanoarchitectures have appropriate biocompatibility. Altogether, the nanoarchitectured PPy/CS may find application in the regeneration of bone defect. - Highlights: • The formation mechanism of PPy nanoarchitectures was proposed. • CS acted as biofunctional dopant and morphology-directing agent in PPy forming. • PPy-CS nanoarchitectures were dependent on the Py/CS ratio.

  9. Diopside-Fluorapatite-Wollastonite Based Bioactive Glasses and Glass-ceramics =

    Science.gov (United States)

    Kansal, Ishu

    Bioactive glasses and glass-ceramics are a class of biomaterials which elicit special response on their surface when in contact with biological fluids, leading to strong bonding to living tissue. This particular trait along with good sintering ability and high mechanical strength make them ideal materials for scaffold fabrication. The work presented in this thesis is directed towards understanding the composition-structure-property relationships in potentially bioactive glasses designed in CaO-MgO-P2O5-SiO2-F system, in some cases with added Na2O. The main emphasis has been on unearthing the influence of glass composition on molecular structure, sintering ability and bioactivity of phosphosilicate glasses. The parent glass compositions have been designed in the primary crystallization field of the pseudo-ternary system of diopside (CaO•MgO•2SiO2) - fluorapatite (9CaO•3P2O5•CaF2) - wollastonite (CaO•SiO2), followed by studying the impact of compositional variations on the structure-property relationships and sintering ability of these glasses. All the glasses investigated in this work have been synthesized via melt-quenching route and have been characterized for their molecular structure, sintering ability, chemical degradation and bioactivity using wide array of experimental tools and techniques. It has been shown that in all investigated glass compositions the silicate network was mainly dominated by Q2 units while phosphate in all the glasses was found to be coordinated in orthophosphate environment. The glass compositions designed in alkali-free region of diopside - fluorapatite system demonstrated excellent sintering ability and good bioactivity in order to qualify them as potential materials for scaffold fabrication while alkali-rich bioactive glasses not only hinder the densification during sintering but also induce cytotoxicity in vitro, thus, are not ideal candidates for in vitro tissue engineering. One of our bioglass compositions with low sodium

  10. Effect of temperature on sulphate reduction, growth rate and growth yield in five psychrophilic sulphate-reducing bacteria from Arctic sediments

    DEFF Research Database (Denmark)

    Knoblauch, C.; Jørgensen, BB

    1999-01-01

    Five psychrophilic sulphate-reducing bacteria (strains ASv26, LSv21, PSv29, LSv54 and LSv514) isolated from Arctic sediments were examined for their adaptation to permanently low temperatures, All strains grew at -1.8 degrees C, the freezing point of sea water, but their optimum temperature...... and T(opt). For strains LSv21 and LSv514, however, growth yields were highest at the lowest temperatures, around 0 degrees C. The results indicate that psychrophilic sulphate-reducing bacteria are specially adapted to permanently low temperatures by high relative growth rates and high growth yields...... at in site conditions....

  11. Determination of Oversulphated Chondroitin Sulphate and Dermatan Sulphate in unfractionated heparin by (1)H-NMR - Collaborative study for quantification and analytical determination of LoD.

    Science.gov (United States)

    McEwen, I; Mulloy, B; Hellwig, E; Kozerski, L; Beyer, T; Holzgrabe, U; Wanko, R; Spieser, J-M; Rodomonte, A

    2008-12-01

    Oversulphated Chondroitin Sulphate (OSCS) and Dermatan Sulphate (DS) in unfractionated heparins can be identified by nuclear magnetic resonance spectrometry (NMR). The limit of detection (LoD) of OSCS is 0.1% relative to the heparin content. This LoD is obtained at a signal-to-noise ratio (S/N) of 2000:1 of the heparin methyl signal. Quantification is best obtained by comparing peak heights of the OSCS and heparin methyl signals. Reproducibility of less than 10% relative standard deviation (RSD) has been obtained. The accuracy of quantification was good.

  12. Sulphate Potasium Extraction From Banana Stem Ash with Bleaching Earth Waste Liquid

    OpenAIRE

    Edahwati, Luluk

    2010-01-01

    Sulphate potassium is one of the important chemistry compound for industrial at our country, usually for fertilizerindustry. Therefore, necessary done sulphate potassium maker watchfulness from various ingredient that containsulphate potassium compound. Among others with extract banana stem ash. Watchfulness methodology that is withmix banana stem ash with aquadest (20 gram ash/1 water litre) in temperature 100oc during 30 minutes and stirringrotation 300 rpm. Ash extract that got reaction wi...

  13. Formation of sulphite, cysteic acid and taurine from sulphate by the egg embryo

    International Nuclear Information System (INIS)

    Chapeville, F.; Fromageot, P.

    1959-01-01

    It is shown that the formation of taurine from sulphate by the chicken embryo involves the reduction of sulphate to sulphite (I), the synthesis of cysteic acid (II) and its decarboxylation (Ill). The reaction (I) takes place in the vitellin sac. The reaction (II) results from the condensation of the sulphite with a-amino-acrylic acid and is carried out by the yolk. The enzymes responsible for the decarboxylation (III) are distributed both in the embryo and in its appendages. (author) [fr

  14. Susceptibility of salmonid fish to poisons under estuarine conditions. I. Zinc sulphate

    Energy Technology Data Exchange (ETDEWEB)

    Herbert, D W.M.; Wakeford, A C

    1964-01-01

    The resistance of yearling rainbow trout and Atlantic salmon smolts to zinc sulphate increases with salinity up to 30-40 percent sea water, in which these species can withstand for 2 days respectively 15 and 13 times as much zinc sulphate as on fresh water. Further increase in salinity to 72 percent sea water reduces tolerance for the zinc salt. Salmon smolts were more susceptible to zinc poisoning than trout in fresh water and at all salinities tested.

  15. High dose, fast delivery magnesium sulphate in a 3-year-old acute severe asthmatic

    Directory of Open Access Journals (Sweden)

    John R Elton

    2017-09-01

    Full Text Available Acute severe asthma when respiratory failure is imminent is not addressed in world asthma guidelines. Intravenous magnesium sulphate, salbutamol and aminophylline all have advocates but what order, speed of delivery or dosage is left up to the individual physician treating the patient. A child in respiratory failure was given a large, fast dose of intravenous magnesium sulphate before intravenous salbutamol which relaxed bronchial smooth muscle immediately and tracheal intubation and lung ventilation was avoided. Justification for this treatment is discussed.

  16. Production of ferric sulphate from pyrite by thiobacillus ferrooxidans. Application to uranium ore leaching

    International Nuclear Information System (INIS)

    Rouas, C.

    1988-12-01

    A process for uranium extraction by oxidizing solutions of ferric sulphate produced by T. ferrooxidans from pyrite is developed. A new counting method specific of T. ferrooxidans is designed. An uranium resistant wild strain, with oxidizing properties as high as the strain ATCC 19859, is isolated. Optimal conditions for ferric sulphate production from pyrite are defined (pH 1.8, density of the medium 1.2%, pyrite granulometry [fr

  17. The bioavailability of four zinc oxide sources and zinc sulphate in broiler chickens

    OpenAIRE

    Veldkamp, T.; Diepen, van, J.T.M.; Bikker, P.

    2014-01-01

    Zinc is an essential trace element for all farm animal species. It is commonly included in animal diets as zinc oxide, zinc sulphate or organically bound zinc. Umicore Zinc Chemicals developed zinc oxide products with different mean particle sizes. Umicore Zinc Chemicals requested Wageningen UR Livestock Research to determine the bioavailability of four zinc oxide sources and zinc sulphate in broiler chickens. A precise estimate of the bioavailability of zinc sources is required both for fulf...

  18. Solubilities of sodium nitrate, sodium nitrite, and sodium aluminate in simulated nuclear waste

    International Nuclear Information System (INIS)

    Reynolds, D.A.; Herting, D.L.

    1984-09-01

    Solubilities were determined for sodium nitrate, sodium nitrite, and sodium aluminate in synthetic nuclear waste liquor. Solubilities were determined as a function of temperature and solution composition (concentrations of sodium hydroxide, sodium nitrate, sodium nitrite, and sodium aluminate). Temperature had the greatest effect on the solubilities of sodium nitrate and sodium nitrite and a somewhat lesser effect on sodium aluminate solubility. Hydroxide had a great effect on the solubilities of all three salts. Other solution components had minor effects. 2 references, 8 figures, 11 tables

  19. Fluoride glass fiber optics

    CERN Document Server

    Aggarwal, Ishwar D

    1991-01-01

    Fluoride Glass Fiber Optics reviews the fundamental aspects of fluoride glasses. This book is divided into nine chapters. Chapter 1 discusses the wide range of fluoride glasses with an emphasis on fluorozirconate-based compositions. The structure of simple fluoride systems, such as BaF2 binary glass is elaborated in Chapter 2. The third chapter covers the intrinsic transparency of fluoride glasses from the UV to the IR, with particular emphasis on the multiphonon edge and electronic edge. The next three chapters are devoted to ultra-low loss optical fibers, reviewing methods for purifying and

  20. Multiple Glass Ceilings

    OpenAIRE

    Russo, Giovanni; Hassink, Wolter

    2011-01-01

    Both vertical (between job levels) and horizontal (within job levels) mobility can be sources of wage growth. We find that the glass ceiling operates at both margins. The unexplained part of the wage gap grows across job levels (glass ceiling at the vertical margin) and across the deciles of the intra-job-level wage distribution (glass ceiling at the horizontal margin). This implies that women face many glass ceilings, one for each job level above the second, and that the glass ceiling is a p...