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Sample records for sodium carbonate concentration

  1. Effect of ion concentrations on uranium absorption from sodium carbonate solutions

    International Nuclear Information System (INIS)

    Traut, D.E.; El Hazek, N.M.T.; Palmer, G.R.; Nichols, I.L.

    1979-01-01

    The effect of various ion concentrations on uranium absorption from a sodium carbonate solution by a strong-base, anion resin was investigated in order to help assure an adequate uranium supply for future needs. The studies were conducted to improve the recovery of uranium from in situ leach solutions by ion exchange. The effects of carbonate, bicarbonate, chloride, and sulfate ions were examined. Relatively low (less than 5 g/l) concentrations of chloride, sulfate, and bicarbonate were found to be detrimental to the absorption of uranium. High (greater than 10 g/l) carbonate concentrations also adversely affected the uranium absorption. In addition, the effect of initial resin form was investigated in tests of the chloride, carbonate, and bicarbonate forms; resin form was shown to have no effect on the absorption of uranium

  2. Effect of Sodium Carbonate Concentrations on the Formation and Mechanism of Regenerated Silk Fibroin Nanofibers by Electrospinning

    Directory of Open Access Journals (Sweden)

    Hao Dou

    2014-01-01

    Full Text Available Degumming is the first process for the preparation of all silk-based products. In this paper, effect of sodium carbonate concentrations for silk degumming on the formation of electrospun silk fibroin nanofibers was investigated and the reason for the silk electrospinning process was explained for the first time by differences from the microstructure of regenerated silk fibroin. With increasing the sodium carbonate concentration, microstructure both in the aqueous solutions and in the electrospinning solutions transformed from nanofibrils to nanoparticles, leading to obvious changes on rheological property; electrospinning solutions with nanofibrils behaved like the native silk dope and owned remarkably higher viscosity than the solutions with nanoparticles showing very low viscosity. More interestingly, nanofibrils favored the formation of silk nanofibers with ease, and even nanofibers could be electrospun at concentration 2%. However, nanoparticles were completely unable to generate nanofibers at high spinning concentration 8%. Importance of sodium carbonate concentrations is heavily emphasized for impacting the microstructure types and further influencing the electrospinning performance of regenerated silk. Hence, sodium carbonate concentrations provide a controllable choice for the preparation of silk-based electrospun biomaterials with desired properties.

  3. The determination of hydroxide and carbonate in concentrated sodium chloride solutions

    NARCIS (Netherlands)

    Roolvink, W.B.; Bos, M.

    1980-01-01

    A computer method for the determination of carbonate and hydroxide in concentrated (2.89 M) sodium chloride solutions is described. The method is based on multiparametric curve-fitting and can also be applied to salts of dibasic acids with unknown equilibrium constants. The systematic error is not

  4. Desorption of Reactive Red 198 from activated carbon prepared from walnut shells: effects of temperature, sodium carbonate concentration and organic solvent dose

    Directory of Open Access Journals (Sweden)

    Zohreh Alimohamadi

    2017-04-01

    Full Text Available This study investigated the effect of temperature, different concentrations of sodium carbonate,and the dose of organic solvent on the desorption of Reactive Red 198 dye from dye-saturated activated carbon using batch and continuous systems. The results of the batch desorption test showed 60% acetone in water as the optimum amount. However, when the concentration of sodium carbonate was raised, the dye desorption percentage increased from 26% to 42% due to economic considerations; 15 mg/L of sodium carbonate was selected to continue the processof desorption. Increasing the desorption temperature can improve the dye desorption efficiency.According to the column test results, dye desorption concentration decreased gradually with the passing of time. The column test results showed that desorption efficiency and the percentage of dye adsorbed decreased; however, it seemed to stabilize after three repeated adsorption/desorption cycles. The repeated adsorption–desorption column tests (3 cycles showed that the activated carbon which was prepared from walnut shell was a suitable and economical adsorbent for dye removal.

  5. Sodium-carbonate co-substituted hydroxyapatite ceramics

    Directory of Open Access Journals (Sweden)

    Zoltan Z. Zyman

    2013-12-01

    Full Text Available Powders of sodium-carbonate co-substituted hydroxyapatite, having sodium content in the range of 0.25–1.5 wt.% with a 0.25 wt.% step, were prepared by a precipitation-solid state reaction route. Compacts of the powders were sintered in a CO2 flow (4 mL/min at 1100 °C for 2 h. The sintered ceramics contained sodium and carbonate ions in the ranges of 0–1.5 wt.% and 1.3–6 wt.%, respectively, which are typical impurity concentrations in biological apatite. A relationship between sodium and carbonate contents and the type of carbonate substitution was found. The total carbonate content progressively increased with the sodium content. The obtained ceramics showed an AB-type carbonate substitution. However, the substitution became more B-type as the sodium content increased. As a result, the carbonation was almost B-type (94 % for the highest sodium content (1.5 wt.%.

  6. The Effects of Voltage and Concentration of Sodium Bicarbonate on Electrochemical Synthesis of Ethanol from Carbon Dioxide Using Brass as Cathode

    Science.gov (United States)

    Ramadan, Septian; Fariduddin, Sholah; Rizki Aminudin, Afianti; Kurnia Hayatri, Antisa; Riyanto

    2017-11-01

    The effects of voltage and concentration of sodium bicarbonate were investigated to determine the optimum conditions of the electrochemical synthesis process to convert carbon dioxide into ethanol. The conversion process is carried out using a sodium bicarbonate electrolyte solution in an electrochemical synthesis reactor equipped with a cathode and anode. As the cathode was used brass, while as the anode carbon was utilized. Sample of the electrochemical synthesis process was analyzed by gas chromatography to determine the content of the compounds produced. The optimum electrochemical synthesis conditions to convert carbon dioxide into ethanol are voltage and concentration of sodium bicarbonate are 3 volts and 0.4 M with ethanol concentration of 1.33%.

  7. A Simple Quantitative Synthesis: Sodium Chloride from Sodium Carbonate.

    Science.gov (United States)

    Gold, Marvin

    1988-01-01

    Describes a simple laboratory procedure for changing sodium carbonate into sodium chloride by adding concentrated HCl to cause the reaction and then evaporating the water. Claims a good stoichiometric yield can be obtained in one three-hour lab period. Suggests using fume hood for the reaction. (ML)

  8. Dosage of trace carbon in sodium (1963); Dosage de traces de carbone dans le sodium (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Sannier, J; Vasseur, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    A wet method for dosing carbon in sodium has been developed. The carbon is oxidised in a vacuum using Van SLYKE'S solution. The carbonic acid formed is measured volumetrically; its purity can be controlled by chromatographic analysis. The results obtained show that this method makes it possible to measure carbon in concentrations of about 10 ppm. (authors) [French] Une methode de dosage par voie humide du carbone dans le sodium a ete mise au point. L'oxydation du carbone par la solution de Van SLYKE est realisee sous vide. Le gaz carbonique forme est dose volumetriquement; sa purete peut etre controlee par analyse chromatographique. Les resultats obtenus montrent que cette methode permet de doser des teneurs en carbone de l'ordre de 10 ppm. (auteurs)

  9. The foil equilibration method for carbon in sodium

    Energy Technology Data Exchange (ETDEWEB)

    Borgstedt, H; Frees, G; Peric, Z [Karlsruhe Nuclear Research Center, Institute of Materials and Solid State Research, Karlsruhe (Germany)

    1980-05-01

    Among the non-metallic impurities in sodium, carbon plays an important role since at high temperatures the structural materials exposed to sodium are subject to carburization and decarburization depending on the carbon activity of the sodium. Carburization of austenitic stainless steels leads to reduction in ductility and fatigue properties whereas decarburization results in a decrease in the high temperature creep strength. A knowledge of the carbon activities in sodium will help understanding of the carbon transfer phenomena in operating sodium systems of the fast reactors, and also carbon diffusion, microstructural stability and mechanical behaviour of materials under different service conditions. An understanding of the carbon behaviour in sodium becomes difficult in view of the complexities of the different species present as elemental carbon, carbide, acetylide, carbonate, and cyanide. Carbon estimation techniques for sodium presently in use are: chemical analytical methods, on-line carbon monitors, and oil equilibration method. Various chemical methods have been developed for the estimation of different species like acetylide, cyanide, carbonate, elemental carbon, and total carbon in sodium. All these methods are time consuming and subject to various errors. The on-line monitors developed for carbon in sodium are able to give continuous indication of carbon activities and have higher sensitivity than the chemical methods. A still more simple method for the determination of carbon activities is by the foil equilibration first published by Natesan et al. Because of its simplicity like the vanadium wire equilibration for oxygen it is being used widely for the estimation of carbon activities in sodium systems. Carbon concentrations in operating sodium systems estimated by this procedure by applying solubility relation to carbon activities have yielded very low values of carbon, lower than the sensitivity limits of the chemical estimation methods. Foil

  10. The foil equilibration method for carbon in sodium

    International Nuclear Information System (INIS)

    Borgstedt, H.; Frees, G.; Peric, Z.

    1980-01-01

    Among the non-metallic impurities in sodium, carbon plays an important role since at high temperatures the structural materials exposed to sodium are subject to carburization and decarburization depending on the carbon activity of the sodium. Carburization of austenitic stainless steels leads to reduction in ductility and fatigue properties whereas decarburization results in a decrease in the high temperature creep strength. A knowledge of the carbon activities in sodium will help understanding of the carbon transfer phenomena in operating sodium systems of the fast reactors, and also carbon diffusion, microstructural stability and mechanical behaviour of materials under different service conditions. An understanding of the carbon behaviour in sodium becomes difficult in view of the complexities of the different species present as elemental carbon, carbide, acetylide, carbonate, and cyanide. Carbon estimation techniques for sodium presently in use are: chemical analytical methods, on-line carbon monitors, and oil equilibration method. Various chemical methods have been developed for the estimation of different species like acetylide, cyanide, carbonate, elemental carbon, and total carbon in sodium. All these methods are time consuming and subject to various errors. The on-line monitors developed for carbon in sodium are able to give continuous indication of carbon activities and have higher sensitivity than the chemical methods. A still more simple method for the determination of carbon activities is by the foil equilibration first published by Natesan et al. Because of its simplicity like the vanadium wire equilibration for oxygen it is being used widely for the estimation of carbon activities in sodium systems. Carbon concentrations in operating sodium systems estimated by this procedure by applying solubility relation to carbon activities have yielded very low values of carbon, lower than the sensitivity limits of the chemical estimation methods. Foil

  11. Combined effect of glycation and sodium carbonate-bicarbonate buffer concentration on IgG binding, IgE binding and conformation of ovalbumin.

    Science.gov (United States)

    Ma, Xiao-juan; Gao, Jin-yan; Chen, Hong-bing

    2013-10-01

    Ovalbumin (OVA) is a major allergen in hen egg. During thermal processing, reducing sugars contained in the hen egg white might easily undergo glycation with OVA, but few studies have been conducted on its corresponding immunoreactivity changes. The aim of the present study was to assess changes of the antigenicity, potential allergenicity and conformation of OVA after glycation in a wet-thermal processing system under different concentrations of sodium carbonate-bicarbonate buffer. IgE binding of the glycated OVA was increased after glycation, and the higher the sodium carbonate-bicarbonate buffer concentration, the higher the IgE binding capacity. The increase in IgE binding of OVA corresponded well with the disruption of the disulfide bond, which exposed the epitopes initially buried. Antigenicity of the glycated OVA was increased, and the amount of the increase varied among samples treated under different buffer concentrations. Glycation increased the allergenic potential for OVA, with the amount of increase varying with different sodium carbonate-bicarbonate buffer concentrations. © 2013 Society of Chemical Industry.

  12. Application of a commercial diffusion type carbon meter in a sodium circuit

    International Nuclear Information System (INIS)

    Bhat, N.P.; Borgstedt, H.U.; Peric, Z.; Witting, G.

    1980-01-01

    The exchange of carbon between structural materials and liquid sodium influences the mechanical properties of components of the cooling circuits. Therefore, the estimation of the carbon content of the alkali metal and the knowledge of its carburizing potential is of importance. Since some years the measurement of the carburizing potential of sodium is easy to perform by the application of the foil equilibration method which leads to good results in spite of the very low carbon concentrations in the liquid metal. Thin foils (0.025 to 0.125 mm) of Fe-18Cr-8Ni-C alloy (corresponding to stainless steel type AISI 304) are immersed in sodium at 550 to 700 deg. C for 200 to 400 hours. The equilibrium of the carbon distribution must be reached. Chemical analyses of the steel tabs and relation of concentration to activity of carbon lead to information on the carbon concentration in the sodium, if the saturation concentration of carbon in sodium is known. The method gives arbitrary values over a longer period of time. The time needed for equilibration and analysis causes a delay for the getting of results. Therefore, there is a need for instruments which are capable to measure carbon directly in the circuits and give continuously information on the actual carbon activities in the fluid. Until 1975 only one carbon meter was commercially available. One unit in was tested a chemical analytical sodium circuit

  13. Behaviour of carbon-bearing impurity suspensions in sodium loops

    Energy Technology Data Exchange (ETDEWEB)

    Kozlov, F A; Zagorulko, Yu I; Alexseev, V V [Institute of Physics and Power Engineering, Obninsk (USSR)

    1980-05-01

    The experimental estimation results of the carbon-bearing impurity particle sizes in sodium by the sedimentometric analysis methods are presented. The techniques and results of the mass transfer calculations between the sodium flows contained the carbon-bearing impurity disperse phase, and the channel walls, the carbon particles solution kinetics and the soluble carbon near-wall concentration in channel with allowance for the flow-wall mass transfer processes, are given. (author)

  14. Behaviour of carbon-bearing impurity suspensions in sodium loops

    International Nuclear Information System (INIS)

    Kozlov, F.A.; Zagorulko, Yu.I.; Alexseev, V.V.

    1980-01-01

    The experimental estimation results of the carbon-bearing impurity particle sizes in sodium by the sedimentometric analysis methods are presented. The techniques and results of the mass transfer calculations between the sodium flows contained the carbon-bearing impurity disperse phase, and the channel walls, the carbon particles solution kinetics and the soluble carbon near-wall concentration in channel with allowance for the flow-wall mass transfer processes, are given. (author)

  15. Dosage of trace carbon in sodium (1963)

    International Nuclear Information System (INIS)

    Sannier, J.; Vasseur, A.

    1963-01-01

    A wet method for dosing carbon in sodium has been developed. The carbon is oxidised in a vacuum using Van SLYKE'S solution. The carbonic acid formed is measured volumetrically; its purity can be controlled by chromatographic analysis. The results obtained show that this method makes it possible to measure carbon in concentrations of about 10 ppm. (authors) [fr

  16. Scientific Opinion on the safety evaluation of the active substances, sodium carbonate peroxyhydrate coated with sodium carbonate and sodium silicate, bentonite, sodium chloride, sodium carbonate for use in active food contact materials

    OpenAIRE

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF)

    2013-01-01

    This scientific opinion of the Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the powder mixture of the active substances sodium carbonate peroxyhydrate coated with sodium carbonate and sodium silicate (FCM substance No 1009), bentonite (CAS No 1302-78-9, FCM No 393), sodium chloride (CAS No 7647-14-5, FCM No 985), sodium carbonate (CAS No 497-19-8, FCM No 1008) which are intended to be used as combined oxygen generator and carbon...

  17. 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 ...

  18. Reaction velocity of sodium hydration in humid air and sodium carbonation in humid carbon dioxide atmosphere. Fundamental study on sodium carbonate process in FBR bulk sodium coolant disposal technology

    International Nuclear Information System (INIS)

    Tadokoro, Yutaka; Yoshida, Eiichi

    1999-11-01

    A sodium carbonate processing method, which changes sodium to sodium carbonate and/or sodium bicarbonate by humid carbon dioxide, has been examined and about to be applied to large test loops dismantling. However, that the basic data regarding the progress of the reaction is insufficient on the other hand, is a present condition. The present report therefore aims at presenting basic data regarding the reaction velocity of sodium hydration in humid air and sodium carbonation in humid carbon dioxide atmosphere, and observing the reaction progress, for the application to large test loops dismantling. The test result is summarized as follows. (1) Although the reaction velocity of sodium varied with sodium specimen sizes and velocity measurement methods, the reaction velocity of sodium hydration was in about 0.16 ∼ 0.34 mmh -1 (0.016 ∼ 0.033g cm -2 h -1 , 6.8x10 -4 ∼ 1.4x10 -3 mol cm -2 h -1 ) and that of sodium carbonation was in about 0.16 ∼ 0.27mmh -1 (0.016 ∼ 0.023g cm -2 h -1 , 6.8x10 -4 ∼ 1.1x10 -3 mol cm -2 h -1 ) (26 ∼ 31degC, RH 100%). (2) The reaction velocity of sodium in carbon dioxide atmosphere was greatly affected by vapor partial pressure (absolutely humidity). And the velocity was estimated in 0.08 ∼ 0.12mmh -1 (0.008 ∼ 0.012g cm -2 h -1 , 3.4x10 -4 ∼ 5.2x10 -4 mol cm -2 h -1 ) in the carbon dioxide atmosphere, whose temperature of 20degC and relative humidity of 80% are assumed real sodium carbonate process condition. (3) By the X-ray diffraction method, NaOH was found in humid air reaction product. Na 2 CO 3 , NaHCO 3 were found in carbon dioxide atmosphere reaction product. It was considered that Sodium changes to NaOH, and subsequently to NaHCO 3 through Na 2 CO 3 . (4) For the application to large test loops dismantling, it is considered possible to change sodium to a target amount of sodium carbonate (or sodium bicarbonate) by setting up gas supply quantity and also processing time appropriately according to the surface area

  19. Separation of uranium from sodium carbonate - sodium bicarbonate eluate by ion exchange method

    International Nuclear Information System (INIS)

    Sakane, Kohji; Hirotsu, Takahiro; Fujii, Ayako; Katoh, Shunsaku; Sugasaka, Kazuhiko

    1982-01-01

    The ion exchange method was used for separating uranium from the eluate (0.5 N Na 2 CO 3 -0.5 N NaHCO 3 ) that was obtained in the extraction process of uranium from natural sea water by using the titanium-activated carbon composite adsorbent. Uranium in the eluate containing 3 mg/1 uranium was adsorbed by ion exchange resin (Amberlite IRA-400), and was eluted with the eluant (5 % NaCl-0.5 % Na 2 CO 3 ). The concentration ratio of uranium in the final concentrated-eluate became more than 20 times. The eluting solution to the adsorbent and the eluant to the resin could be repeatedly used in the desorption-ion exchange process. Sodium carbonate was consumed at the desorption step, and sodium bicarbonate was consumed at the ion exchange step. The concentration ratio of uranium was found to decrease as chloride ion in the eluate increased. (author)

  20. Separation of uranium from sodium carbonate-sodium bicarbonate eluate by ion exchange method

    International Nuclear Information System (INIS)

    Sakane, Kohji; Hirotsu, Takahiro; Fujii, Ayako; Katoh, Shunsaku; Sugasaka, Kazuhiko

    1982-01-01

    The ion exchange method was used for separating uranium from the eluate (0.5 N Na 2 CO 3 -0.5 N NaHCO 3 ) that was obtained in the extraction process of uranium from natural sea water by using the titanium-activated carbon composite adsorbent. Uranium in the eluate containing 3 mg/l uranium was adsorbed by ion exchange resin (Amberlite IRA-400), and was eluted with the eluent (5% NaCl-0.5% Na 2 CO 3 ). The concentration ratio of uranium in the final concentrated-eluate became more than 20 times. The eluting solution to the adsorbent and the eluant to the resin could be repeatedly used in the desorption-ion exchange process. Sodium carbonate was consumed at the desorption step, and sodium bicarbonate was consumed at the ion exchange step. The concentration ratio of uranium was found to decrease as chloride ion in the eluate increased. (author)

  1. Sodium Hypochlorite and Sodium Bromide Individualized and Stabilized Carbon Nanotubes in Water

    KAUST Repository

    Xu, Xuezhu

    2017-09-20

    Aggregation is a major problem for hydrophobic carbon nanomaterials such as carbon nanotubes (CNTs) in water because it reduces the effective particle concentration, prevents particles from entering the medium, and leads to unstable electronic device performances when a colloidal solution is used. Molecular ligands such as surfactants can help the particles to disperse, but they tend to degrade the electrical properties of CNTs. Therefore, self-dispersed particles without the need for surfactant are highly desirable. We report here, for the first time to our knowledge, that CNT particles with negatively charged hydrophobic/water interfaces can easily self-disperse themselves in water via pretreating the nanotubes with a salt solution with a low concentration of sodium hypochlorite (NaClO) and sodium bromide (NaBr). The obtained aqueous CNT suspensions exhibit stable and superior colloidal performances. A series of pH titration experiments confirmed the presence and role of the electrical double layers on the surface of the salted carbon nanotubes and of functional groups and provided an in-depth understanding of the phenomenon.

  2. Sodium Hypochlorite and Sodium Bromide Individualized and Stabilized Carbon Nanotubes in Water

    KAUST Repository

    Xu, Xuezhu; Zhou, Jian; Colombo, Veronica; Xin, Yangyang; Tao, Ran; Lubineau, Gilles

    2017-01-01

    Aggregation is a major problem for hydrophobic carbon nanomaterials such as carbon nanotubes (CNTs) in water because it reduces the effective particle concentration, prevents particles from entering the medium, and leads to unstable electronic device performances when a colloidal solution is used. Molecular ligands such as surfactants can help the particles to disperse, but they tend to degrade the electrical properties of CNTs. Therefore, self-dispersed particles without the need for surfactant are highly desirable. We report here, for the first time to our knowledge, that CNT particles with negatively charged hydrophobic/water interfaces can easily self-disperse themselves in water via pretreating the nanotubes with a salt solution with a low concentration of sodium hypochlorite (NaClO) and sodium bromide (NaBr). The obtained aqueous CNT suspensions exhibit stable and superior colloidal performances. A series of pH titration experiments confirmed the presence and role of the electrical double layers on the surface of the salted carbon nanotubes and of functional groups and provided an in-depth understanding of the phenomenon.

  3. Separation of uranium from sodium carbonate - sodium bicarbonate eluate by ion exchange method

    Energy Technology Data Exchange (ETDEWEB)

    Sakane, Kohji; Hirotsu, Takahiro; Fujii, Ayako; Katoh, Shunsaku; Sugasaka, Kazuhiko (Government Industrial Research Inst., Shikoku, Takamatsu (Japan))

    1982-09-01

    The ion exchange method was used for separating uranium from the eluate (0.5 N Na/sub 2/CO/sub 3/-0.5 N NaHCO/sub 3/) that was obtained in the extraction process of uranium from natural sea water by using the titanium-activated carbon composite adsorbent. Uranium in the eluate containing 3 mg/1 uranium was adsorbed by ion exchange resin (Amberlite IRA-400), and was eluted with the eluant (5 % NaCl-0.5 % Na/sub 2/CO/sub 3/). The concentration ratio of uranium in the final concentrated-eluate became more than 20 times. The eluting solution to the adsorbent and the eluant to the resin could be repeatedly used in the desorption-ion exchange process. Sodium carbonate was consumed at the desorption step, and sodium bicarbonate was consumed at the ion exchange step. The concentration ratio of uranium was found to decrease as chloride ion in the eluate increased.

  4. Separation of uranium from sodium carbonate-sodium bicarbonate eluate by ion exchange method

    Energy Technology Data Exchange (ETDEWEB)

    Sakane, K.; Hirotsu, T.; Fujii, A.; Katoh, S.; Sugasaka, K. (Government Industrial Research. Inst., Shikoku, Takamatsu (Japan))

    1982-01-01

    The ion exchange method was used for separating uranium from the eluate (0.5 N Na/sub 2/CO/sub 3/-0.5 N NaHCO/sub 3/) that was obtained in the extraction process of uranium from natural sea water by using the titanium-activated carbon composite adsorbent. Uranium in the eluate containing 3 mg/l uranium was adsorbed by ion exchange resin (Amberlite IRA-400), and was eluted with the eluent (5% NaCl-0.5% Na/sub 2/CO/sub 3/). The concentration ratio of uranium in the final concentrated-eluate became more than 20 times. The eluting solution to the adsorbent and the eluant to the resin could be repeatedly used in the desorption-ion exchange process. Sodium carbonate was consumed at the desorption step, and sodium bicarbonate was consumed at the ion exchange step. The concentration ratio of uranium was found to decrease as chloride ion in the eluate increased.

  5. 21 CFR 582.1742 - Sodium carbonate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium carbonate. 582.1742 Section 582.1742 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1742 Sodium carbonate. (a) Product. Sodium carbonate. (b) Conditions of use. This substance...

  6. Analysis of carbon transport in the EBR-II and FFTF primary sodium systems

    International Nuclear Information System (INIS)

    Snyder, R.B.; Natesan, K.; Kassner, T.F.

    1976-01-01

    An analysis of the carburization-decarburization behavior of austenitic stainless steels in the primary heat-transport systems of the EBR-II and FFTF has been made that is based upon a kinetic model for the diffusion process and the surface area of steel in contact with flowing sodium at various temperatures in the two systems. The analysis was performed for operating conditions that result in sodium outlet temperatures of 474 and 566 0 C in the FFTF and 470 0 C in the EBR-II. If there was no external source of carbon to the system, i.e., other than the carbon initially present in the steel and the sodium, the dynamic-equilibrium carbon concentrations calculated for the FFTF primary sodium were approximately 0.025 and approximately 0.065 ppm for the 474 and 566 0 C outlet temperatures, respectively, and approximately 0.018 ppm for the EBR-II primary system. The analysis indicated that a carbon-source rate of approximately 250 g/y would be required to increase the carbon concentration of the EBR-II sodium to the measured range of approximately 0.16--0.19 ppm. An evaluation of possible carbon sources and the amount of carbonaceous material introduced into the reactor cover gas and sodium suggests that the magnitude of the calculated contamination rate is reasonable. For a 566 0 C outlet temperature, carbonaceous material would have to be introduced into the FFTF primary system at a rate approximately 4--6 times higher than in EBR-II to achieve the same carbon concentration in the sodium in the two systems. Since contamination rates of approximately 1500 g/y are unlikely, high-temperature fuel cladding in the FFTF should exhibit decarburization similar to that observed in laboratory loop systems, in contrast to the minimal compositional changes that result after exposure of Type 316 stainless steel to EBR-II sodium at temperatures between approximately 625 and 650 0 C

  7. 21 CFR 184.1742 - Sodium carbonate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium carbonate. 184.1742 Section 184.1742 Food... Specific Substances Affirmed as GRAS § 184.1742 Sodium carbonate. (a) Sodium carbonate (Na2CO3, CAS Reg. No... ore calcined to impure soda ash and then purified; or (3) synthesized from limestone by the Solvay...

  8. Factors Affecting Dissolution Resistance of AC Anodizing Al in Sodium Carbonate Solution

    International Nuclear Information System (INIS)

    Abou-Krisha, M.

    2001-01-01

    Studies were performed to determine the effect of different factors on the properties and so the dissolution resistance of the anodic film of Al. Conductance and thermometric measurements were applied to evaluate the dissolution rate. The effect of applied AC voltage concentration of sodium carbonate solution, the anodization time and the temperature of sodium carbonate solutions show a parallel increase in the dissolution resistance of studied Al in hydrochloride acid. The results show that films formed by sodium carbonate solution were of porous type and have pronounced high resistance. Scanning electron microscope and x-ray diffraction further examined the films. The anodic and cathodic behavior and the effect of the scanning rate on the polarization of Al in sodium carbonate solution were studied. The regression analysis was applied to all results. (Author)

  9. Chemistry of carbon in dynamic sodium

    Energy Technology Data Exchange (ETDEWEB)

    Lievens, F; Casteels, F [SCK/CEN, Mol (Belgium)

    1980-05-01

    The chemistry of carbon in sodium is described by its chemical activity measurements using alloy monitor foils, by its behaviour in the heat exchanger of the Na 2 sodium loop after 60,000 hours of operation, and by measurements with on-line meters. Efforts toward the identification of the carbon chemical states present in dynamic sodium, and responsible for the carbon chemical activity, are described. (author)

  10. Chemistry of carbon in dynamic sodium

    International Nuclear Information System (INIS)

    Lievens, F.; Casteels, F.

    1980-01-01

    The chemistry of carbon in sodium is described by its chemical activity measurements using alloy monitor foils, by its behaviour in the heat exchanger of the Na 2 sodium loop after 60,000 hours of operation, and by measurements with on-line meters. Efforts toward the identification of the carbon chemical states present in dynamic sodium, and responsible for the carbon chemical activity, are described. (author)

  11. Carbon transport in sodium systems

    International Nuclear Information System (INIS)

    Martin Espigares, M.; Lapena, J.; La Torre, M. de

    1983-01-01

    Carbon activities in dynamic non isothermal sodium system are determined using an equilibratium method. Foils of Fe-18 w% Cr-8 W% Ni alloy with low carbon content (in the as received condition) are exposed to dynamic liquid sodium in the temperature range between 450 0 C and 700 0 C. The analysis was used to evaluate the carburization-decarburization behaviour of type 304 stainless steel exposed to sodium. (author)

  12. Measurement of carbon thermodynamic activity in sodium

    Energy Technology Data Exchange (ETDEWEB)

    Kozlov, F A; Zagorulko, Yu I; Kovalev, Yu P; Alekseev, V V [Institute of Physics and Power Engineering, Obninsk (USSR)

    1980-05-01

    The report presents the brief outline on system of carbon activity detecting system in sodium (SCD), operating on the carbon-permeable membrane, of the methods and the results of testing it under the experimental circulating loop conditions. The results of carbon activity sensor calibration with the use of equilibrium samples of XI8H9, Fe -8Ni, Fe -12Mn materials are listed. The behaviour of carbon activity sensor signals in sodium under various transitional conditions and hydrodynamic perturbation in the circulating loop, containing carbon bearing impurities in the sodium flow and their deposits on the surfaces flushed by sodium, are described. (author)

  13. Metal corrosion in a supercritical carbon dioxide - liquid sodium power cycle.

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Robert Charles; Conboy, Thomas M.

    2012-02-01

    A liquid sodium cooled fast reactor coupled to a supercritical carbon dioxide Brayton power cycle is a promising combination for the next generation nuclear power production process. For optimum efficiency, a microchannel heat exchanger, constructed by diffusion bonding, can be used for heat transfer from the liquid sodium reactor coolant to the supercritical carbon dioxide. In this work, we have reviewed the literature on corrosion of metals in liquid sodium and carbon dioxide. The main conclusions are (1) pure, dry CO{sub 2} is virtually inert but can be highly corrosive in the presence of even ppm concentrations of water, (2) carburization and decarburization are very significant mechanism for corrosion in liquid sodium especially at high temperature and the mechanism is not well understood, and (3) very little information could be located on corrosion of diffusion bonded metals. Significantly more research is needed in all of these areas.

  14. Process for the production of sodium carbonate anhydrate

    OpenAIRE

    Oosterhof, H.; Van Rosmalen, G.M.; Witkamp, G.J.; De Graauw, J.

    2000-01-01

    The invention is directed to a process for the production of sodium carbonate-anhydrate having a bulk density of at least 800 kg/m, said process comprising: providing a suspension of solid sodium carbonate and/or solid sodium bicarbonate and/or solid double salts at least comprising one of sodium carbonate and sodium bicarbonate, in a mixture containing water and an organic, water miscible or partly water miscible solvent, which solvent influences the transition temperature below which sodium...

  15. Parametric Effect of Sodium Hydroxide and Sodium Carbonate on the Potency of a Degreaser

    OpenAIRE

    Babatope Abimbola Olufemi

    2016-01-01

    Experimental and statistical analysis was carried out on the comparative effect of sodium hydroxide and sodium carbonate on the potency of a laboratory produced degreaser in this work. The materials used include; octadecyl benzene sulphonic acid, sodium hydroxide, sodium carbonate, sodium metasilicate, carboxyl methyl cellulose (C.M.C), formadelhyde, perfume, colourant and distilled water. Different samples of degreaser were produced with varying composition of sodium hydroxide and sodium car...

  16. Measurement of carbon activity in sodium by Fe-Mn 20% alloy, and by strainless austenitic steel 304L and 316L

    International Nuclear Information System (INIS)

    Oberlin, C.; Saint Paul, P.; Baque, P.; Champeix, L.

    1980-01-01

    Precise knowledge of carbon activity in sodium used as coolant in fast breeder reactors, is essential for continuous survey of carburization-decarburization processes. Carbon activity can be periodically surveyed by measuring the carbon concentration or by hot trap like metal alloy strip placed in sodium loop. In fact, in equilibrium, activity of carbon in sodium is equal to the activity in metal alloy. Thus if the relation between concentration of carbon and it activity in the alloy is known, it is possible to estimate the activity of carbon in sodium. Materials to be used should have high solubility in carbon at the needed temperature. They should quickly attain equilibrium with sodium and they should not contain impurities that can affect the results. Materials chosen according to these criteria were Fe-Mn 20%, stainless austenitic steel AISI 304L and 316L

  17. A computational model for the carbon transfer in stainless steel sodium systems

    International Nuclear Information System (INIS)

    Casadio, S.; Scibona, G.

    1980-01-01

    A method is proposed of computing the carbon transfer in the type 316, 304 and 321 stainless steels in sodium environment as a function of temperature, exposure time and carbon concentration in the sodium. The method is based on the criteria developed at ANL by introducing some simplifications and takes also into account the correlations obtained at WARD. Calculated carbon profiles are compared both with experimental data and with the results available by the other computer methods. The limits for quantitative predictions of the stainless steel carburization or decarburization exposed in a specific environment are discussed. (author)

  18. Process for the production of sodium carbonate anhydrate

    NARCIS (Netherlands)

    Oosterhof, H.; Van Rosmalen, G.M.; Witkamp, G.J.; De Graauw, J.

    2000-01-01

    The invention is directed to a process for the production of sodium carbonate-anhydrate having a bulk density of at least 800 kg/m<3>, said process comprising: providing a suspension of solid sodium carbonate and/or solid sodium bicarbonate and/or solid double salts at least comprising one of sodium

  19. Specialists' meeting on carbon in sodium. Summary report

    International Nuclear Information System (INIS)

    1980-05-01

    The purpose of the meeting was to provide a forum for the exchange of views on: the chemistry and thermodynamics of carbon in sodium; the analysis and monitoring of carbon in sodium; the behaviour of carbon in sodium circuits; and the implications of the above in LMFBRs. The technical parts of the meeting were divided into five major sessions

  20. Specialists' meeting on carbon in sodium. Summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-05-01

    The purpose of the meeting was to provide a forum for the exchange of views on: the chemistry and thermodynamics of carbon in sodium; the analysis and monitoring of carbon in sodium; the behaviour of carbon in sodium circuits; and the implications of the above in LMFBRs. The technical parts of the meeting were divided into five major sessions.

  1. Comparative solubilisation of potassium carbonate, sodium bicarbonate and sodium carbonate in hot dimethylformamide: application of cylindrical particle surface-controlled dissolution theory.

    Science.gov (United States)

    Forryan, Claire L; Compton, Richard G; Klymenko, Oleksiy V; Brennan, Colin M; Taylor, Catherine L; Lennon, Martin

    2006-02-07

    A surface-controlled dissolution of cylindrical solid particles model is applied to potassium carbonate, sodium bicarbonate and sodium carbonate in dimethylformamide at elevated temperatures. Previously published data for the dissolution of potassium carbonate is interpreted assuming a cylindrical rather than a spherical shape of the particles, the former representing a closer approximation to the true shape of the particles as revealed by scanning electron microscopy. The dissolution kinetics of sodium carbonate and sodium bicarbonate in dimethylformamide at 100 degrees C were investigated via monitoring of the deprotonation of 2-cyanophenol with dissolved solid to form the 2-cyanophenolate anion that was detected with UV-visible spectroscopy. From fitting of experimental results to theory, the dissolution rate constant, k, for the dissolutions of potassium carbonate, sodium bicarbonate and sodium carbonate in dimethylformamide at 100 degrees C were found to have the values of (1.0 +/- 0.1) x 10(-7) mol cm(-2) s(-1), (5.5 +/- 0.3) x 10(-9) mol cm(-2) s(-1) and (9.7 +/- 0.8) x 10(-9) mol cm(-2) s(-1), respectively.

  2. Solubility of ammonium metavanadate in ammonium carbonate and sodium bicarbonate solutions at 25 deg C

    International Nuclear Information System (INIS)

    Fedorov, P.I.; Andreev, V.K.; Slotvinskij-Sidak, N.P.

    1978-01-01

    Solubility at 25 deg C has been studied in the system ammonium metavanadate - sodium bicarbonate - water which is a stable section of the corresponding quaternary mutual system. In the eutonic point the content of ammonium metavanadate is 4.95% and of sodium bicarbonate 12.1%. The crystallization branch of ammonium metavanadate has been studied in the system ammonium metavanadate - ammonium carbonate - water at 25 deg C. Metavanadate solubility attains minimum (0.14%) at ammonium carbonate concentration 2.6%. Three sections have been studied of the quaternary system ammonium - metavanadate - ammonium carbonate - sodium bicarbonate-water at 25 deg C in the crystallization region of ammonium metavanadate at a ratio of sodium bicarbonate to ammonium carbonate 3:1, 1:1, and 1:3. A region of minimum solubility of ammonium metavanadate has been detected (0.1%)

  3. Analysis and monitoring of carbon in sodium

    Energy Technology Data Exchange (ETDEWEB)

    Lievens, F; Parmentier, C [SCK/CEN, Mol (Belgium)

    1980-05-01

    Chemical analyses used by SCK/CEN at Mol Belgium, in the carbon mass transfer studies include on-line activity measurements, and off-line carbon determinations on sodium samples and on alloys equilibrated with the carbon activity in the loop sodium. For carbon activity measurements efforts were directed to the development of EMF and diffusion type carbon meters. The Monitor tab technique was used for calibration. Chemical off-line analyses were developed for identification and measurement of total carbon and for carbon chemical states in the ppb range. Analysed chemical states are carbides, Carbonates, Carbonyl and Cyanide. (author)

  4. Analysis and monitoring of carbon in sodium

    International Nuclear Information System (INIS)

    Lievens, F.; Parmentier, C.

    1980-01-01

    Chemical analyses used by SCK/CEN at Mol Belgium, in the carbon mass transfer studies include on-line activity measurements, and off-line carbon determinations on sodium samples and on alloys equilibrated with the carbon activity in the loop sodium. For carbon activity measurements efforts were directed to the development of EMF and diffusion type carbon meters. The Monitor tab technique was used for calibration. Chemical off-line analyses were developed for identification and measurement of total carbon and for carbon chemical states in the ppb range. Analysed chemical states are carbides, Carbonates, Carbonyl and Cyanide. (author)

  5. Gold nanoparticle/multi-walled carbon nanotube modified glassy carbon electrode as a sensitive voltammetric sensor for the determination of diclofenac sodium.

    Science.gov (United States)

    Afkhami, Abbas; Bahiraei, Atousa; Madrakian, Tayyebeh

    2016-02-01

    A simple and highly sensitive sensor for the determination of diclofenac sodium based on gold nanoparticle/multi-walled carbon nanotube modified glassy carbon electrode is reported. Scanning electron microscopy along with energy dispersive X-ray spectroscopy, electrochemical impedance spectroscopy, cyclic voltammetry and square wave voltammetry was used to characterize the nanostructure and performance of the sensor and the results were compared with those obtained at the multi-walled carbon nanotube modified glassy carbon electrode and bare glassy carbon electrode. Under the optimized experimental conditions diclofenac sodium gave linear response over the range of 0.03-200μmolL(-1). The lower detection limits were found to be 0.02μmolL(-1). The effect of common interferences on the current response of DS was investigated. The practical application of the modified electrode was demonstrated by measuring the concentration of diclofenac sodium in urine and pharmaceutical samples. This revealed that the gold nanoparticle/multiwalled carbon nanotube modified glassy carbon electrode shows excellent analytical performance for the determination of diclofenac sodium in terms of a very low detection limit, high sensitivity, very good accuracy, repeatability and reproducibility. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Gold nanoparticle/multi-walled carbon nanotube modified glassy carbon electrode as a sensitive voltammetric sensor for the determination of diclofenac sodium

    International Nuclear Information System (INIS)

    Afkhami, Abbas; Bahiraei, Atousa; Madrakian, Tayyebeh

    2016-01-01

    A simple and highly sensitive sensor for the determination of diclofenac sodium based on gold nanoparticle/multi-walled carbon nanotube modified glassy carbon electrode is reported. Scanning electron microscopy along with energy dispersive X-ray spectroscopy, electrochemical impedance spectroscopy, cyclic voltammetry and square wave voltammetry was used to characterize the nanostructure and performance of the sensor and the results were compared with those obtained at the multi-walled carbon nanotube modified glassy carbon electrode and bare glassy carbon electrode. Under the optimized experimental conditions diclofenac sodium gave linear response over the range of 0.03–200 μmol L −1 . The lower detection limits were found to be 0.02 μmol L −1 . The effect of common interferences on the current response of DS was investigated. The practical application of the modified electrode was demonstrated by measuring the concentration of diclofenac sodium in urine and pharmaceutical samples. This revealed that the gold nanoparticle/multiwalled carbon nanotube modified glassy carbon electrode shows excellent analytical performance for the determination of diclofenac sodium in terms of a very low detection limit, high sensitivity, very good accuracy, repeatability and reproducibility. - Highlights: • GCE was modified with multiwalled carbon nanotube and gold nanoparticles. • AuNP/MWCNT/GCE was used for the determination of diclofenac sodium. • Modified electrode was characterized by SEM, EDS and EIS. • The proposed method showed excellent analytical figures of merit. • This sensor was used for the determination of diclofenac sodium in real samples.

  7. Gold nanoparticle/multi-walled carbon nanotube modified glassy carbon electrode as a sensitive voltammetric sensor for the determination of diclofenac sodium

    Energy Technology Data Exchange (ETDEWEB)

    Afkhami, Abbas, E-mail: afkhami@basu.ac.ir; Bahiraei, Atousa; Madrakian, Tayyebeh

    2016-02-01

    A simple and highly sensitive sensor for the determination of diclofenac sodium based on gold nanoparticle/multi-walled carbon nanotube modified glassy carbon electrode is reported. Scanning electron microscopy along with energy dispersive X-ray spectroscopy, electrochemical impedance spectroscopy, cyclic voltammetry and square wave voltammetry was used to characterize the nanostructure and performance of the sensor and the results were compared with those obtained at the multi-walled carbon nanotube modified glassy carbon electrode and bare glassy carbon electrode. Under the optimized experimental conditions diclofenac sodium gave linear response over the range of 0.03–200 μmol L{sup −1}. The lower detection limits were found to be 0.02 μmol L{sup −1}. The effect of common interferences on the current response of DS was investigated. The practical application of the modified electrode was demonstrated by measuring the concentration of diclofenac sodium in urine and pharmaceutical samples. This revealed that the gold nanoparticle/multiwalled carbon nanotube modified glassy carbon electrode shows excellent analytical performance for the determination of diclofenac sodium in terms of a very low detection limit, high sensitivity, very good accuracy, repeatability and reproducibility. - Highlights: • GCE was modified with multiwalled carbon nanotube and gold nanoparticles. • AuNP/MWCNT/GCE was used for the determination of diclofenac sodium. • Modified electrode was characterized by SEM, EDS and EIS. • The proposed method showed excellent analytical figures of merit. • This sensor was used for the determination of diclofenac sodium in real samples.

  8. Sodium phthalamates as corrosion inhibitors for carbon steel in aqueous hydrochloric acid solution

    International Nuclear Information System (INIS)

    Flores, Eugenio A.; Olivares, Octavio; Likhanova, Natalya V.; Dominguez-Aguilar, Marco A.; Nava, Noel; Guzman-Lucero, Diego; Corrales, Monica

    2011-01-01

    Highlights: → N-Alkyl-sodium phthalamates as corrosion inhibitors for industry in acidic medium. → Compounds behaved as mixed type inhibitors and followed Langmuir adsorption isotherm. → Efficiencies were proportional to aliphatic chain length and inhibitor concentration. → Iron complexes and chelates with phthalamates contributed to carbon steel protection. - Abstract: Three compounds of N-alkyl-sodium phthalamates were synthesized and tested as corrosion inhibitors for carbon steel in 0.5 M aqueous hydrochloric acid. Tests showed that inhibitor efficiencies were related to aliphatic chain length and dependent on concentration. N-1-n-tetradecyl-sodium phthalamate displayed moderate efficiency against uniform corrosion, 42-86% at 25 deg. C and 25-60% at 40 o C. Tests indicated that compounds behave as mixed type inhibitors where molecular adsorption on steel followed Langmuir isotherm, whereas thermodynamic suggested that a physisorption process occurred. XPS analysis confirmed film formation on surface, where Fe +2 complexes and Fe +2 chelates with phthalamates prevented steel from further corrosion.

  9. Reducing biomass recalcitrance via mild sodium carbonate pretreatment.

    Science.gov (United States)

    Mirmohamadsadeghi, Safoora; Chen, Zhu; Wan, Caixia

    2016-06-01

    This study examined the effects of mild sodium carbonate (Na2CO3) pretreatment on enzymatic hydrolysis of different feedstocks (i.e., corn stover, Miscanthus, and switchgrass). The results showed that sodium carbonate pretreatment markedly enhanced the sugar yields of the tested biomass feedstocks. The pretreated corn stover, Miscanthus, and switchgrass gave the glucose yields of 95.1%, 62.3%, and 81.3%, respectively, after enzymatic hydrolysis. The above glucose yields of pretreated feedstocks were 2-4 times that of untreated ones. The pretreatment also enhanced the xylose yields, 4 times for corn stover and 20 times for both Miscanthus and switchgrass. Sodium carbonate pretreatment removed 40-59% lignin from the tested feedstocks while preserving most of cellulose (sodium carbonate pretreatment was effective for reducing biomass recalcitrance and subsequently improving the digestibility of lignocellulosic biomass. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. THE SODIUM PREVALENCE IN CARBONATED SOFT DRINKS SOLD IN BRAZIL

    Directory of Open Access Journals (Sweden)

    Sandra Fernanda Nunes

    2012-12-01

    Full Text Available The carbonated soft drinks intake has changed the children eating habits. This factor may be directly associated with arterial hypertension due the high consumption of sodium present in foods and drinks industrialized. This study was to compare sodium levels between two different types of carbonated soft drinks, carbonated sugar drinks and diet drinks to define what type of drink has the lowest sodium content and alerting healthcare professionals about the presence of sodium in industrialized beverages. The study included labels of carbonated soft drinks n = 33 – sugar drinks (n = 21 or diet drinks (n = 12 – of five different flavors.All carbonated soft drinks evaluated have sodium in its composition. However, the sodium presence in carbonated sugar drinks was significantly lower when compared with carbonated diet drinks (69.05 ± 16.55 vs. 145.30 ± 47.36mg Na/l, respectively.Studies to identify children's eating habits related with increased consumption of foods and drinks manufactured are needed to identify, reduce and prevent high blood pressure.

  11. Mixed Solvent Reactive Recrystallization of Sodium Carbonate

    NARCIS (Netherlands)

    Gaertner, R.S.

    2005-01-01

    Investigation of the reactive recrystallization of trona (sodium sesquicarbonate) and sodium bicarbonate to sodium carbonate (soda) in a mixed solvent led to the design of several alternative, less energy consumptive, economically very attractive process routes for the production of soda from all

  12. Leaching of uranium from Syrian phosphorite (sodium carbonate-bicarbonate)

    International Nuclear Information System (INIS)

    Abou-Jamous, J.Kh.

    1991-01-01

    The leaching of uranium from Syrian phosphorite by sodium carbonate-bicarbonate solution has been studied, using a batch technique. Parameters influencing percentage extraction of uranium that are considered and studies in this work are: Leachant concentration, particle size, heat treatment, leachant renewal, phosphorite renewal and contact time. All measurements of uranium from aqueous solutions were carried out by fluorometry. (author). 12 refs., 4 figs., 1 tab

  13. Laboratory-scale sodium-carbonate aggregate concrete interactions

    International Nuclear Information System (INIS)

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

    1983-09-01

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

  14. Carbon in sodium: a status review of the USA R and D work

    International Nuclear Information System (INIS)

    McCown, J.J.; Bagnall, C.

    1979-01-01

    A review is presented concerning R and D work on carbon in sodium with reference to LMFBR primary coolant circuits. The chemistry of carbon in sodium, analysis and monitoring of carbon in sodium, carbon meters, and problems of carbon in sodium are described. 31 references

  15. Enhanced electrochemical stability of carbon-coated antimony nanoparticles with sodium alginate binder for sodium-ion batteries

    Directory of Open Access Journals (Sweden)

    Jianmin Feng

    2018-04-01

    Full Text Available The poor cycling stability of antimony during a repeated sodium ion insertion and desertion process is the key issue, which leads to an unsatisfactory application as an anode material in a sodium-ion battery. Addressed at this, we report a facile two-step method to coat antimony nanoparticles with an ultrathin carbon layer of few nanometers (denoted Sb@C NPs for sodium-ion battery anode application. This carbon layer could buffer the volume change of antimony in the charge-discharge process and improve the battery cycle performance. Meanwhile, this carbon coating could also enhance the interfacial stability by firmly connecting the sodium alginate binders through its oxygen-rich surface. Benefitted from these advantages, an improved initial discharge capacity (788.5 mA h g−1 and cycling stability capacity (553 mA h g−1 after 50 times cycle have been obtained in a battery using Sb@C NPs as anode materials at 50 mA g−1. Keywords: Sodium-ion battery, Antimony, Sodium alginate, Liquid-phase reduction, Carbon coating

  16. Pyro-oxidation of plutonium spent salts with sodium carbonate

    International Nuclear Information System (INIS)

    Bourges, G.; Godot, A.; Valot, C.; Devillard, D.

    2001-01-01

    The purification of plutonium generates spent salts, which are temporarily stored in a nuclear building. A development programme for pyrochemical treatment is in progress to stabilize and concentrate these salts in order to reduce the quantities for long-term disposal. The treatment, inspired by work previously done by LANL, consists of a pyro-oxidation of the salt with sodium carbonate to convert the actinides into oxides, then of a vacuum distillation to separate the oxides from the volatile salt matrix. Pyro-oxidation of NaCl/KCl base spent salts first produces a 'black salt' which contains more than 97% of the initial actinides. XRD analyses indicate PuO 2 as major plutonium species and sodium plutonates or plutonium sub-oxides PuO 2-x can also be identified. Next appears a 'white salt' containing less than 500 ppm of plutonium, which meets the operational criterion for LLW discard. For these salts, the pyro-oxidation process in and of itself is expected to reduce the quantities to be stored on-site by more than one-third. The pyro-oxidation of CaCl 2 /NaCl base americium extraction salts leads to oxides PuO 2 and probably AmO 2 , but the yield of concentration in the black salt is lower and the white salt cannot be discarded as LLW. During vacuum distillation, excess carbonate can dissociate and damage the efficiency of the process. Appropriate chlorine sparging at the end of the oxidation can eliminate this carbonate. (authors)

  17. Measurement of the activity coefficient of carbon in steels in liquid sodium

    International Nuclear Information System (INIS)

    Surville, G.

    1983-06-01

    In sodium cooled fast reactors carbon is both a carbon impurity and element of structural materials. Carbon transfert through liquid sodium can produce carburization or decarburization of structural materials. Carbon content in sodium is determined with thin foils of austenitic alloys, when equilibrium is reached thermodynamic activity of carbon in sodium is deduced from carbon activity in alloys. Studied alloys are FeMn 20%, FeNi 30%, Z2CN 18-10 and Z3CND17-13. Carbon activity of alloys in sodium was between 5.10 -3 and 10 -1 at 600 and 650 0 C. Calibration was obtained with the alloys FeNi 30% in gaseous mixtures He-CO-CO 2 of known activity [fr

  18. Rheological behavior of high-concentration sodium caseinate dispersions.

    Science.gov (United States)

    Loveday, Simon M; Rao, M Anandha; Creamer, Lawrence K; Singh, Harjinder

    2010-03-01

    Apparent viscosity and frequency sweep (G', G'') data for sodium caseinate dispersions with concentrations of approximately 18% to 40% w/w were obtained at 20 degrees C; colloidal glass behavior was exhibited by dispersions with concentration >or=23% w/w. The high concentrations were obtained by mixing frozen powdered buffer with sodium caseinate in boiling liquid nitrogen, and allowing the mixtures to thaw and hydrate at 4 degrees C. The low-temperature G'-G'' crossover seen in temperature scans between 60 and 5 degrees C was thought to indicate gelation. Temperature scans from 5 to 90 degrees C revealed gradual decrease in G' followed by plateau values. In contrast, G'' decreased gradually and did not reach plateau values. Increase in hydrophobicity of the sodium caseinate or a decrease in the effective volume fraction of its aggregates may have contributed to these phenomena. The gelation and end of softening temperatures of the dispersions increased with the concentration of sodium caseinate. From an Eldridge-Ferry plot, the enthalpy of softening was estimated to be 29.6 kJ mol(-1). The results of this study should be useful for creating new products with high concentrations of sodium caseinate.

  19. A Small-Scale Capsule Test for Investigating the Sodium-Carbon Dioxide Reaction

    International Nuclear Information System (INIS)

    Kim, B. H.; Choi, J. H.; Suk, S. D.; Kim, J. M.; Choi, B. H.; Kim, B. H.; Hahn, D. H.

    2007-01-01

    The utilization of modular sodium-to-supercritical CO 2 heat exchangers may yield significant improvements for an overall plant energy utilization. The consequences of a failure of the sodium CO 2 heat exchanger boundary, however, would involve the blowdown and intermixing of high-pressure CO 2 in a sodium pool, causing a pressurization which may threaten the structural integrity of the heat exchanger. Available data seems to indicate that the chemical reaction between sodium and CO 2 would likely produce sodium oxides, sodium carbonate, carbon and carbon monoxide. Information on the kinetics of the sodium-CO 2 reaction is virtually non-existent

  20. Corrosion performance of advanced structural materials in sodium.

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-05-16

    Test Facility, and Clinch River Breeder Reactor. Among the nonmetallic elements discussed, oxygen is deemed controllable and its concentration in sodium can be maintained in sodium for long reactor life by using cold-trap method. It was concluded that among the cold-trap and getter-trap methods, the use of cold trap is sufficient to achieve oxygen concentration of the order of 1 part per million. Under these oxygen conditions in sodium, the corrosion performance of structural materials such as austenitic stainless steels and ferritic steels will be acceptable at a maximum core outlet sodium temperature of {approx}550 C. In the current sodium compatibility studies, the oxygen concentration in sodium will be controlled and maintained at {approx}1 ppm by controlling the cold trap temperature. The oxygen concentration in sodium in the forced convection sodium loop will be controlled and monitored by maintaining the cold trap temperature in the range of 120-150 C, which would result in oxygen concentration in the range of 1-2 ppm. Uniaxial tensile specimens are being exposed to flowing sodium and will be retrieved and analyzed for corrosion and post-exposure tensile properties. Advanced materials for sodium exposure include austenitic alloy HT-UPS and ferritic-martensitic steels modified 9Cr-1Mo and NF616. Among the nonmetallic elements in sodium, carbon was assessed to have the most influence on structural materials since carbon, as an impurity, is not amenable to control and maintenance by any of the simple purification methods. The dynamic equilibrium value for carbon in sodium systems is dependent on several factors, details of which were discussed in the earlier report. The current sodium compatibility studies will examine the role of carbon concentration in sodium on the carburization-decarburization of advanced structural materials at temperatures up to 650 C. Carbon will be added to the sodium by exposure of carbon-filled iron tubes, which over time will enable

  1. Corrosion performance of advanced structural materials in sodium

    International Nuclear Information System (INIS)

    Natesan, K.; Momozaki, Y.; Li, M.; Rink, D.L.

    2012-01-01

    Clinch River Breeder Reactor. Among the nonmetallic elements discussed, oxygen is deemed controllable and its concentration in sodium can be maintained in sodium for long reactor life by using cold-trap method. It was concluded that among the cold-trap and getter-trap methods, the use of cold trap is sufficient to achieve oxygen concentration of the order of 1 part per million. Under these oxygen conditions in sodium, the corrosion performance of structural materials such as austenitic stainless steels and ferritic steels will be acceptable at a maximum core outlet sodium temperature of ∼550 C. In the current sodium compatibility studies, the oxygen concentration in sodium will be controlled and maintained at ∼1 ppm by controlling the cold trap temperature. The oxygen concentration in sodium in the forced convection sodium loop will be controlled and monitored by maintaining the cold trap temperature in the range of 120-150 C, which would result in oxygen concentration in the range of 1-2 ppm. Uniaxial tensile specimens are being exposed to flowing sodium and will be retrieved and analyzed for corrosion and post-exposure tensile properties. Advanced materials for sodium exposure include austenitic alloy HT-UPS and ferritic-martensitic steels modified 9Cr-1Mo and NF616. Among the nonmetallic elements in sodium, carbon was assessed to have the most influence on structural materials since carbon, as an impurity, is not amenable to control and maintenance by any of the simple purification methods. The dynamic equilibrium value for carbon in sodium systems is dependent on several factors, details of which were discussed in the earlier report. The current sodium compatibility studies will examine the role of carbon concentration in sodium on the carburization-decarburization of advanced structural materials at temperatures up to 650 C. Carbon will be added to the sodium by exposure of carbon-filled iron tubes, which over time will enable carbon to diffuse through iron and

  2. A Small-Scale Capsule Test for Investigating the Sodium-Carbon Dioxide Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, B. H.; Choi, J. H.; Suk, S. D.; Kim, J. M.; Choi, B. H.; Kim, B. H.; Hahn, D. H

    2007-01-15

    The utilization of modular sodium-to-supercritical CO{sub 2} heat exchangers may yield significant improvements for an overall plant energy utilization. The consequences of a failure of the sodium CO{sub 2} heat exchanger boundary, however, would involve the blowdown and intermixing of high-pressure CO{sub 2} in a sodium pool, causing a pressurization which may threaten the structural integrity of the heat exchanger. Available data seems to indicate that the chemical reaction between sodium and CO{sub 2} would likely produce sodium oxides, sodium carbonate, carbon and carbon monoxide. Information on the kinetics of the sodium-CO{sub 2} reaction is virtually non-existent.

  3. Carbon in sodium - A review of work in the UK

    International Nuclear Information System (INIS)

    Thorley, A.W.; Hobdell, M.R.

    1980-01-01

    It has been shown experimentally that when a difference in carbon potential exists between two points in a sodium circuit, carbon will move from regions of high carbon potential to regions of low carbon potential. Instrumental in this transport process is the liquid sodium which provides an efficient. means of transport between sources and sinks. In terms of operation of LMFBRs the point of concern is that impairment of mechanical properties may occur if significant amounts of carbon are gained or lost from structures exposed to sodium. In the UK the behaviour of carbon in liquid sodium is being studied at AERE Harwell, Berkeley Nuclear Laboratories (BNL), the Dounreay Nuclear Establishment (DNE), and the Risley Nuclear Laboratories (RNL). The scope of this review reflects the type of work being carried out at various establishments and presents our current views on certain topics. A survey of the UK position and an indication of where more work is required is also included in the paper. Specialist material is provided in the form of appendices

  4. Carbon in sodium - A review of work in the UK

    Energy Technology Data Exchange (ETDEWEB)

    Thorley, A W; Hobdell, M R [CEGB, Berkeley Nuclear Laboratories, Berkely, Gloucestershire (United Kingdom)

    1980-05-01

    It has been shown experimentally that when a difference in carbon potential exists between two points in a sodium circuit, carbon will move from regions of high carbon potential to regions of low carbon potential. Instrumental in this transport process is the liquid sodium which provides an efficient. means of transport between sources and sinks. In terms of operation of LMFBRs the point of concern is that impairment of mechanical properties may occur if significant amounts of carbon are gained or lost from structures exposed to sodium. In the UK the behaviour of carbon in liquid sodium is being studied at AERE Harwell, Berkeley Nuclear Laboratories (BNL), the Dounreay Nuclear Establishment (DNE), and the Risley Nuclear Laboratories (RNL). The scope of this review reflects the type of work being carried out at various establishments and presents our current views on certain topics. A survey of the UK position and an indication of where more work is required is also included in the paper. Specialist material is provided in the form of appendices.

  5. Studies on the kinetics of UO2 dissolution in carbonate-bicarbonate medium using sodium hypochlorite as oxidant

    International Nuclear Information System (INIS)

    Sharma, J.N.; Bhattacharya, K.; Swami, R.G.; Tangri, S.K.; Mukherjee, T.K.

    1996-01-01

    The dissolution of UO 2 in carbonate-bicarbonate solutions containing sodium hypochlorite as an oxidant has been investigated. The effect of temperature, sodium hypochlorite concentration and stirring speed was examined. In the temperature range of 303 to 318 K, the leaching reaction displayed linear kinetics. Apparent activation energy obtained from the differential approach was found to be 57 kJ mol -1 . This relatively high activation energy value indicates a chemically controlled behavior of UO 2 dissolution. The order of reaction with respect to sodium hypochlorite concentration was found to be unity. (author). 18 refs., 6 figs

  6. Sodium Carbonate is Saltier Than Sodium Chloride to Sodium-Depleted Rats.

    Science.gov (United States)

    St John, Steven J; McBrayer, Anya M; Krauskopf, Erin E

    2017-10-01

    In a series of behavioral experiments in the 1960s, G.R. Morrison identified several unique features of the taste of Na2CO3 to rats; namely, it is 1) considerably more intense than NaCl at isomolar concentrations, 2) avoided at 10 times lower concentrations than NaCl to thirsty rats, 3) preferred at 10 times lower concentrations than NaCl in sodium-depleted rats. He also demonstrated its qualitatively similarity to NaCl. In Experiment 1, we confirmed and extended many of Morrison's observations. Rats were injected with furosemide on 3 occasions to stimulate a sodium appetite. After each depletion, rats were given a brief-access taste test in a lickometer presenting, in random order, water and 7 concentrations of salt. One test used NaCl (0.028-0.89 M, quarter log steps), another used Na2CO3, and the third used Na2CO3, but at a tenfold lower concentration range (0.0028-0.089 M). Rats licked NaCl in an inverted-U shaped concentration-response function peaking at 0.158-0.281 M. As Morrison's results predicted, rats licked Na2CO3 in nearly identical fashion, but at a tenfold lower concentration range (peak at 0.0158-0.028 M). In a second experiment, furosemide-treated rats were repeatedly tested with the lower Na2CO3 range but mixed in the epithelial sodium channel blocker amiloride at various concentrations (3-300 μM, half log steps). Amiloride reduced licking for Na2CO3 and shifted the peak response rightward up to about half a log unit. Thus, this "super-saltiness" of Na2CO3 to rats is at least partly amiloride-dependent. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Correlation for predicting aerosol concentration in sodium spray fires

    International Nuclear Information System (INIS)

    Marimuthu, K.

    2001-01-01

    Aerosol behaviour computer codes are reported for the study of time-dependent airborne aerosol concentration in a containment. The use of available computer codes requires a thorough knowledge of the various rate processes employed to describe the aerosol behaviour. The present work describes a simple empirical equation to calculate sodium fire aerosol concentration with respect to time in a containment and is applicable to sodium spray fire conditions. Sodium spray fire aerosol concentration values obtained using this simplified approach agree reasonably well with experimental results. The empirical equation described in the present work is incorporated in the spray fire code NACOM and the code calculated values of aerosol concentration agreement with the sodium spray fire experimental results is reasonably good. (author)

  8. Altering plasma sodium concentration rapidly changes blood pressure during haemodialysis.

    Science.gov (United States)

    Suckling, Rebecca J; Swift, Pauline A; He, Feng J; Markandu, Nirmala D; MacGregor, Graham A

    2013-08-01

    Plasma sodium is increased following each meal containing salt. There is an increasing interest in the effects of plasma sodium concentration, and it has been suggested that it may have direct effects on blood pressure (BP) and possibly influences endothelial function. Experimental increases of plasma sodium concentration rapidly raise BP even when extracellular volume falls. Ten patients with end-stage renal failure established on haemodialysis were studied during the first 2 h of dialysis without fluid removal during this period. They were randomized to receive haemodialysis with (i) dialysate sodium concentration prescribed to 135 mmol/L and (ii) 145 mmol/L in random order in a prospective, single-blinded crossover study. BP measurements and blood samples were taken every 30 min. Pre-dialysis sitting BP was 137/76 ± 7/3 mmHg. Lower dialysate sodium concentration (135 mmol/L) reduced plasma sodium concentration [139.49 ± 0.67 to 135.94 ± 0.52 mmol/L (P area under the curve (AUC) 15823.50 ± 777.15 (mmHg)min] compared with 145 mmol/L [AUC 17018.20 ± 1102.17 (mmHg)min], mean difference 1194.70 ± 488.41 (mmHg)min, P < 0.05. There was a significant positive relationship between change in plasma sodium concentration and change in systolic BP. This direct relationship suggests that a fall of 1 mmol/L in plasma sodium concentration would be associated with a 1.7 mmHg reduction in systolic BP (P < 0.05). The potential mechanism for the increase in BP seen with salt intake may be through small but significant changes in plasma sodium concentration.

  9. Thermodynamics of aqueous carbonate solutions including mixtures of sodium carbonate, bicarbonate, and chloride

    Energy Technology Data Exchange (ETDEWEB)

    Peiper, J.C.; Pitzer, K.S.

    1982-01-01

    Recently the authors examined electrochemical-cell data leading to values of the activity coefficient for aqueous sodium bicarbonate. Since that preliminary analysis, new experimental measurements have been published which contribute significantly to the overall thermodynamic understanding of (sodium carbonate + sodium bicarbonate + carbonic acid). In this more extensive examination we consider a wide variety of measurements leading to activity coefficients of Na/sub 2/CO/sub 3/ and NaHCO/sub 3/ from 273 to 323 K and to relative molar enthalpies and heat capacities at 298.15 K. Tables of thermodynamic quantities at selected temperatures are included. 47 references, 2 figures, 6 tables.

  10. Measurement of carbon activity of sodium using nickel tabs and the Harwell Carbon Meter - Preliminary experience

    International Nuclear Information System (INIS)

    Blundell, A.; Thorley, A.W.

    1980-01-01

    Carbon can have an important effect on the mechanical properties of certain constructional materials likely to be used in the LMFBRs. Transfer of carbon will occur between the metal and the sodium at any particular location to bring the chemical potential of carbon in both components to the sam: value. Thus, in a mixed system containing austenitic stainless steel and unstabilized ferritic steel, carbon could be transferred by the sodium from the high carbon activity ferritic to the lower activity austenitic steel. Loss of carbon from the unstabilized ferritic steel leads to a weaker, more ductile material, while carburization of the stainless steel could lead to its embrittlement. Similarly carbon entering the coolant in the form of oil from leaking mechanical pumps could have similar effects on the mechanical property of stainless steels. In the light of these possibilities it is essential to measure the carbon activity of the sodium so that its effect on materials properties can be predicted

  11. Measurement of carbon activity of sodium using nickel tabs and the Harwell Carbon Meter - Preliminary experience

    Energy Technology Data Exchange (ETDEWEB)

    Blundell, A; Thorley, A W [UKAEA, Risley, Warrington, Cheshire (United Kingdom)

    1980-05-01

    Carbon can have an important effect on the mechanical properties of certain constructional materials likely to be used in the LMFBRs. Transfer of carbon will occur between the metal and the sodium at any particular location to bring the chemical potential of carbon in both components to the sam: value. Thus, in a mixed system containing austenitic stainless steel and unstabilized ferritic steel, carbon could be transferred by the sodium from the high carbon activity ferritic to the lower activity austenitic steel. Loss of carbon from the unstabilized ferritic steel leads to a weaker, more ductile material, while carburization of the stainless steel could lead to its embrittlement. Similarly carbon entering the coolant in the form of oil from leaking mechanical pumps could have similar effects on the mechanical property of stainless steels. In the light of these possibilities it is essential to measure the carbon activity of the sodium so that its effect on materials properties can be predicted.

  12. 40 CFR 180.1234 - Sodium carbonate; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Sodium carbonate; exemption from the... Exemptions From Tolerances § 180.1234 Sodium carbonate; exemption from the requirement of a tolerance. An exemption from the requirement of a tolerance is established for residues of sodium carbonate. [70 FR 33363...

  13. Measurement of carbon activity in sodium and steel and the behaviour of carbon-bearing species

    International Nuclear Information System (INIS)

    Rajendran Pillai, S.; Ranganathan, R.; Mathews, C.K.

    1988-01-01

    Carburization or decarburization of structural materials in a sodium system depends on the local differences in carbon activity. The behaviour of carbon-bearing species in sodium influences its carbon activity. In order to understand the behaviour of carbon in these systems, an electrochemical carbon meter was fabricated in our laboratory. The original version of this meter was capable of operating in the temperature range of 850-980 K. Studies are carried out to extend this lower limit of temperature. Employing the carbon meter, experiments were carried out to understand the behaviour of carbon-bearing species. Gas equilibration experiments were also carried out with the same view. A new method for measuring the carbon activity in steels are described which employs the carbon meter. A review on these investigations and the conclusions reached on the behaviour of carbon in fast reactor loops are described

  14. Promoting effect of active carbons on methanol dehydrogenation on sodium carbonate - hydrogen spillover

    OpenAIRE

    Su, S.; Prairie, M.; Renken, A.

    1993-01-01

    Methanol dehydrogenation to formaldehyde was conducted in a fixed-bed flow reactor with sodium carbonate catalyst mixed with active carbons or transition metals. The additives promoted the reaction rate at 880-970 K without modifying formaldehyde selectivity. This effect increases with increasing carbon content in the carbon-carbonate mixture. Activation energy of methanol conversion is the same for the mixture and the carbonate alone. Temperature-programmed desorption experiments showed that...

  15. The effectiveness of sodium hydroxide (NaOH) and sodium carbonate (Na2CO3) on the impurities removal of saturated salt solution

    Science.gov (United States)

    Pujiastuti, C.; Ngatilah, Y.; Sumada, K.; Muljani, S.

    2018-01-01

    Increasing the quality of salt can be done through various methods such as washing (hydro-extraction), re-crystallization, ion exchange methods and others. In the process of salt quality improvement by re-crystallization method where salt product diluted with water to form saturated solution and re-crystallized through heating process. The quality of the salt produced is influenced by the quality of the dissolved salt and the crystallization mechanism applied. In this research is proposed a concept that before the saturated salt solution is recrystallized added a chemical for removal of the impurities such as magnesium ion (Mg), calcium (Ca), potassium (K) and sulfate (SO4) is contained in a saturated salt solution. The chemical reagents that used are sodium hydroxide (NaOH) 2 N and sodium carbonate (Na2CO3) 2 N. This research aims to study effectiveness of sodium hydroxide and sodium carbonate on the impurities removal of magnesium (Mg), calcium (Ca), potassium (K) and sulfate (SO4). The results showed that the addition of sodium hydroxide solution can be decreased the impurity ions of magnesium (Mg) 95.2%, calcium ion (Ca) 45%, while the addition of sodium carbonate solution can decreased magnesium ion (Mg) 66.67% and calcium ion (Ca) 77.5%, but both types of materials are not degradable sulfate ions (SO4). The sodium hydroxide solution more effective to decrease magnesium ion than sodium carbonate solution, and the sodium carbonate solution more effective to decrease calcium ion than sodium hydroxide solution.

  16. Titration of Monoprotic Acids with Sodium Hydroxide Contaminated by Sodium Carbonate.

    Science.gov (United States)

    Michalowski, Tadeusz

    1988-01-01

    Discusses the effects of using carbon dioxide contaminated sodium hydroxide solution as a titrant for a solution of a weak monoprotic acid and the resulting distortion of the titration curve in comparison to one obtained when an uncontaminated titrant is used. (CW)

  17. Sodium and potassium concentrations in floral nectars in relation to ...

    African Journals Online (AJOL)

    Sodium and potassium concentrations have been measured in nectar from a variety of flowering plants visited by honey bees (Apis mellifera capensis). In 18 plant species the mean sodium concentration was 9,8 ± 1,4 mmol (± S.E.), and the mean potassium concentration was 18,7 ± 4,3 mmol. These results are compared ...

  18. Reactions between sodium and various carbon bearing compounds

    Energy Technology Data Exchange (ETDEWEB)

    Raine, A C; Thorley, A W [UKAEA, Risley, Warrington, Cheshire (United Kingdom)

    1980-05-01

    The presence of carbon bearing materials in liquid sodium is undesirable because of their ability to carburise stainless steel components. It has been demonstrated for example that carbon taken up by stainless steels can affect their mechanical properties and that thinner sectioned material such as fuel cladding and the tubing of intermediate heat exchanger may be more sensitive to such effects. Generally speaking, there are a number of potential carbon sources in reactor systems. Some of the sources such as the graphite in neutron shield rods, boron carbide in control rods and carbide fuels are part of the reactor designs while others such as oil in mechanical pumps arid 'coupling-fluids' used to inspect plant components are associated with the respective operation arid inspection of the plant. In this paper it is intended to discuss in general terms the way these various compounds behave in liquid sodium and to assess what effect their presence will have on the materials of construction in fast reactor systems. The paper also reviews the chemistry of the environment in relation to the types of carburizing species which may exist in sodium systems.

  19. Effects of Inulin and Sodium Carbonate in Phosphate-Free Restructured Poultry Steaks

    Science.gov (United States)

    Öztürk, B.; Serdaroğlu, M.

    2017-09-01

    Recently inorganic phosphates used in meat product formulations have caused negative impact on consumers due to their potential health risks. Therefore, utilization of natural ingredients as phosphate replacers has come into prominence as a novel research topic to meet consumer demands for clean-label trends. In this study, we objected to investigate the effects of inulin utilization either in the powder or gelled form, alone or in combination with sodium carbonate on quality of phosphate-free restructured chicken steaks. Total moisture, protein, lipid and ash values of the trial groups were in the range of 71.54-75.46%, 22.60-24.31%, 0.94-1.70% and 1.45-2.13%, respectively. pH of the samples was between 6.18-6.39, significant increments were recorded in samples containing inulin with sodium carbonate. L*, a* and b* values were recorded as 78.92-81.05, 1.76-3.05 and 10.80-11.94, respectively, where use of gelled inulin resulted in changes of L* and a* values. Utilization of inulin in combination with sodium carbonate decreased cook loss and enhanced product yield. Sensory scores in control group with phosphate showed a similar pattern to sensory scores in groups with inulin and sodium carbonate. During storage, purge loss and lipid oxidation rate were similar in control and inulin + sodium carbonate samples. The results showed that use of inulin in combination with sodium carbonate provided equivalent physical, chemical and sensory quality to phosphates in restructured chicken steaks.

  20. Brain intra- and extracellular sodium concentration in multiple sclerosis: a 7 T MRI study.

    Science.gov (United States)

    Petracca, Maria; Vancea, Roxana O; Fleysher, Lazar; Jonkman, Laura E; Oesingmann, Niels; Inglese, Matilde

    2016-03-01

    Intra-axonal accumulation of sodium ions is one of the key mechanisms of delayed neuro-axonal degeneration that contributes to disability accrual in multiple sclerosis. In vivo sodium magnetic resonance imaging studies have demonstrated an increase of brain total sodium concentration in patients with multiple sclerosis, especially in patients with greater disability. However, total sodium concentration is a weighted average of intra- and extra-cellular sodium concentration whose changes reflect different tissue pathophysiological processes. The in vivo, non-invasive measurement of intracellular sodium concentration is quite challenging and the few applications in patients with neurological diseases are limited to case reports and qualitative assessments. In the present study we provide first evidence of the feasibility of triple quantum filtered (23)Na magnetic resonance imaging at 7 T, and provide in vivo quantification of global and regional brain intra- and extra-cellular sodium concentration in 19 relapsing-remitting multiple sclerosis patients and 17 heathy controls. Global grey matter and white matter total sodium concentration (respectively P brain regional level, clusters of increased total sodium concentration and intracellular sodium concentration and decreased intracellular sodium volume fraction were found in several cortical, subcortical and white matter regions when patients were compared with healthy controls (P Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Enhanced Lithium- and Sodium-Ion Storage in an Interconnected Carbon Network Comprising Electronegative Fluorine.

    Science.gov (United States)

    Hong, Seok-Min; Etacheri, Vinodkumar; Hong, Chulgi Nathan; Choi, Seung Wan; Lee, Ki Bong; Pol, Vilas G

    2017-06-07

    Fluorocarbon (C x F y ) anode materials were developed for lithium- and sodium-ion batteries through a facile one-step carbonization of a single precursor, polyvinylidene fluoride (PVDF). Interconnected carbon network structures were produced with doped fluorine in high-temperature carbonization at 500-800 °C. The fluorocarbon anodes derived from the PVDF precursor showed higher reversible discharge capacities of 735 mAh g -1 and 269 mAh g -1 in lithium- and sodium-ion batteries, respectively, compared to the commercial graphitic carbon. After 100 charge/discharge cycles, the fluorocarbon showed retentions of 91.3% and 97.5% in lithium (at 1C) and sodium (at 200 mA g -1 ) intercalation systems, respectively. The effects of carbonization temperature on the electrochemical properties of alkali metal ion storage were thoroughly investigated and documented. The specific capacities in lithium- and sodium-ion batteries were dependent on the fluorine content, indicating that the highly electronegative fluorine facilitates the insertion/extraction of lithium and sodium ions in rechargeable batteries.

  2. Normative data on regional sweat-sodium concentrations of professional male team-sport athletes.

    Science.gov (United States)

    Ranchordas, Mayur K; Tiller, Nicholas B; Ramchandani, Girish; Jutley, Raj; Blow, Andrew; Tye, Jonny; Drury, Ben

    2017-01-01

    The purpose of this paper was to report normative data on regional sweat sweat-sodium concentrations of various professional male team-sport athletes, and to compare sweat-sodium concentrations among sports. Data to this effect would inform our understanding of athlete sodium requirements, thus allowing for the individualisation of sodium replacement strategies. Accordingly, data from 696 athletes (Soccer, n = 270; Rugby, n = 181; Baseball, n = 133; American Football, n = 60; Basketball, n = 52) were compiled for a retrospective analysis. Regional sweat-sodium concentrations were collected using the pilocarpine iontophoresis method, and compared to self-reported measures collected via questionnaire. Sweat-sodium concentrations were significantly higher ( p soccer (43.2 ± 12.0 mmol·L -1 ) or rugby (44.0 ± 12.1 mmol·L -1 ), but with no differences among the N.American or British sports. There were strong positive correlations between sweat-sodium concentrations and self-reported sodium losses in American football ( r s = 0.962, p soccer ( r s = 0.748, p strategies to meet the sodium demands of professional team-sport athletes. Moreover, these novel data suggest that self-reported measures of sodium loss might serve as an effective surrogate in the absence of direct measures; i.e., those which are more expensive or non-readily available.

  3. Crystal growth of calcium carbonate in silk fibroin/sodium alginate hydrogel

    Science.gov (United States)

    Ming, Jinfa; Zuo, Baoqi

    2014-01-01

    As known, silk fibroin-like protein plays a pivotal role during the formation of calcium carbonate (CaCO3) crystals in the nacre sheets. Here, we have prepared silk fibroin/sodium alginate nanofiber hydrogels to serve as templates for calcium carbonate mineralization. In this experiment, we report an interesting finding of calcium carbonate crystal growth in the silk fibroin/sodium alginate nanofiber hydrogels by the vapor diffusion method. The experimental results indicate calcium carbonate crystals obtained from nanofiber hydrogels with different proportions of silk fibroin/sodium alginate are mixture of calcite and vaterite with unusual morphologies. Time-dependent growth study was carried out to investigate the crystallization process. It is believed that nanofiber hydrogels play an important role in the process of crystallization. This study would help in understanding the function of organic polymers in natural mineralization, and provide a novel pathway in the design and synthesis of new materials related unique morphology and structure.

  4. Design and test of a vacuum distillation method for determining carbon in sodium

    International Nuclear Information System (INIS)

    Irmisch, R.; Rettig, D.; Woelke, K.

    1976-08-01

    A method is described for determining total and carbonate carbon in sodium samples until 10 g. Sodium is removed by vacuum distillation at 300 0 C and the carbon in the residue is converted to carbon dioxide by combustion in a stream of air or thermic splitting in a stream of cover gas at 1000 0 C. The carbon dioxide is measured manometrically. It is therefore not necessary to carry out calibration. Distillation and combustion rig are combined with inertgas filled transfer box. Therefore the sodium sample does not get into touch with air. Test of this method was carried out with Na 2 CO 3 and WC. Carbon recoveries were for Na 2 CO 3 between 103 and 107% and for WC between 92 and 96%. The blank value found being 9 μg C and sensitivity 3 μg C. (author)

  5. Cast Stone Formulation At Higher Sodium Concentrations

    International Nuclear Information System (INIS)

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

    2013-01-01

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium

  6. Cast Stone Formulation At Higher Sodium Concentrations

    International Nuclear Information System (INIS)

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

    2014-01-01

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium

  7. Cast Stone Formulation At Higher Sodium Concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Roberts, K. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Edwards, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-02-28

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium

  8. Cast Stone Formulation At Higher Sodium Concentrations

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-10-02

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium

  9. Cast Stone Formulation At Higher Sodium Concentrations

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-09-17

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium

  10. Effect of carbon activity on the creep behaviour of 21/4Cr, 1Mo steel in sodium

    International Nuclear Information System (INIS)

    Cordwell, J.E.; Charnock, W.; Nicholson, R.D.

    1979-02-01

    The creep endurance and creep cracking behaviour of 2 1/4Cr, 1Mo steel in sodium at 475 0 C have been studied at three different sodium carbon activities. Creep endurance was found to increase with increasing carbon activity of the sodium. Tests carried out in high carbon activity sodium were discontinued before fracture. Creep crack initiation displacement at notches decreased with increasing carbon activity, presumably as a result of notch tip carburisation. The plastic zones at the tips of blunt notches in specimens exposed in high carbon activity sodium were preferentially carburised. These observations were similar to those made previously on 9Cr, 1Mo steel. One difference detected metallographically was that in a high carburising environment uniform carburisation was obtained in the 2 1/4Cr, 1Mo steel specimens whereas carburisation gradients were observed in the 9Cr, 1Mo steel. Creep crack propagation rates for given notch opening displacement rates in low and intermediate carbon activity sodium were indistinguishable. However, the strenthening that resulted from the mild carburisation of the specimen in the intermediate carbon activity sodium caused slower notch opening displacement rates and crack propagation rates than in the low carbon activity sodium, when the rates were compared at the same crack length. (author)

  11. Continuous analyzers of hydrogen and carbon in liquid sodium and of hydrocarbon total in protective atmosphere above sodium

    International Nuclear Information System (INIS)

    Pitak, O.; Fresl, M.

    1980-01-01

    The principle is described of a leak detector for detecting water penetration into sodium in a steam generator. The device operates as a diffusion H-meter with an ion pump. Ni or Fe diffusion diaphragm is washed with sodium while diffused hydrogen is pumped and also monitored with the ion pump. Another detector uses the principle of analyzing hydrocarbons in the cover gas above the sodium level. The carrier gas flow for the analyzer divided into measuring and reference parts is passed through a chamber housing the diffusion standard. For measuring carbon content in sodium, the detector analytical part may be completed with a chamber with moisturizing filling for scrubbing gas. Carbon passing through the diffusion Fe diaphragm is scrubbed on the inner wall in the form of CO which is reduced to methane and measured using the detector C-meter. (M.S.)

  12. Solvation behavior of carbonate-based electrolytes in sodium ion batteries.

    Science.gov (United States)

    Cresce, Arthur V; Russell, Selena M; Borodin, Oleg; Allen, Joshua A; Schroeder, Marshall A; Dai, Michael; Peng, Jing; Gobet, Mallory P; Greenbaum, Steven G; Rogers, Reginald E; Xu, Kang

    2016-12-21

    Sodium ion batteries are on the cusp of being a commercially available technology. Compared to lithium ion batteries, sodium ion batteries can potentially offer an attractive dollar-per-kilowatt-hour value, though at the penalty of reduced energy density. As a materials system, sodium ion batteries present a unique opportunity to apply lessons learned in the study of electrolytes for lithium ion batteries; specifically, the behavior of the sodium ion in an organic carbonate solution and the relationship of ion solvation with electrode surface passivation. In this work the Li + and Na + -based solvates were characterized using electrospray mass spectrometry, infrared and Raman spectroscopy, 17 O, 23 Na and pulse field gradient double-stimulated-echo pulse sequence nuclear magnetic resonance (NMR), and conductivity measurements. Spectroscopic evidence demonstrate that the Li + and Na + cations share a number of similar ion-solvent interaction trends, such as a preference in the gas and liquid phase for a solvation shell rich in cyclic carbonates over linear carbonates and fluorinated carbonates. However, quite different IR spectra due to the PF 6 - anion interactions with the Na + and Li + cations were observed and were rationalized with the help of density functional theory (DFT) calculations that were also used to examine the relative free energies of solvates using cluster - continuum models. Ion-solvent distances for Na + were longer than Li + , and Na + had a greater tendency towards forming contact pairs compared to Li + in linear carbonate solvents. In tests of hard carbon Na-ion batteries, performance was not well correlated to Na + solvent preference, leading to the possibility that Na + solvent preference may play a reduced role in the passivation of anode surfaces and overall Na-ion battery performance.

  13. Sodium sampling and impurities determination

    International Nuclear Information System (INIS)

    Docekal, J.; Kovar, C.; Stuchlik, S.

    1980-01-01

    Samples may be obtained from tubes in-built in the sodium facility and further processed or they are taken into crucibles, stored and processed later. Another sampling method is a method involving vacuum distillation of sodium, thus concentrating impurities. Oxygen is determined by malgamation, distillation or vanadium balance methods. Hydrogen is determined by the metal diaphragm extraction, direct extraction or amalgamation methods. Carbon is determined using dry techniques involving burning a sodium sample at 1100 degC or using wet techniques by dissolving the sample with an acid. Trace amounts of metal impurities are determined after dissolving sodium in ethanol. The trace metals are concentrated and sodium excess is removed. (M.S.)

  14. Inhibitive effect of N,N'-Dimethylaminoethanol on carbon steel corrosion in neutral sodium chloride solution, at different temperatures

    Directory of Open Access Journals (Sweden)

    Hassoune Mohammed

    2018-01-01

    Full Text Available The inhibition of carbon steel corrosion in neutral sodium chloride solution by N,N'- Dimethylaminoethanol (DMEA, at different temperatures, was investigated using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS techniques. The results obtained confirm that DMEA is a good organic corrosion inhibitor for carbon steel in 0.5M of NaCl (concentration encountered in the Mediterranean seawater, over the whole range of temperatures studied. The inhibition efficiency (IE% increases with increasing DMEA concentration; it reaches highest value for a concentration around 0.125 mol.L-1. Potentiodynamic polarization data show that, the compound studied in this research predominantly act as anodic-type inhibitor. The EIS study reveals that the addition of DMEA decreases the corrosion rate of carbon steel in neutral sodium chloride solution, due to the fact that the inhibitor molecules are strongly adsorbed on the active sites following Langmuir isotherm, thus leading to the formation of a stable protective film on the steel surface which is able to keep the metal/solution interface in a passive state. Furthermore, the values of the activation parameters, i.e. ΔHa and Ea obtained in this study indicate that the adsorption process of DMEA is endothermic and could be mainly attributed to chemisorption, respectively.

  15. Characteristics of Sodium Polyacrylate/Nano-Sized Carbon Hydrogel for Biomedical Patch.

    Science.gov (United States)

    Park, Jong-Kyu; Seo, Sun-Kyo; Cho, Seungkwan; Kim, Han-Sung; Lee, Chi-Hwan

    2018-03-01

    Conductive hydrogels were prepared for biomedical patch in order to improve the electrical conductivity. Sodium polyacrylate and nano-sized carbon were mixed and fabricated by aqueous solution gelation process in various contents of nano-sized carbon with 0.1, 0.5, 1.0 and 2.0 wt%. Sodium polyacrylate/nano-sized carbon conductive hydrogels were investigated by molecular structure, surface morphology and electrical conductivity. The conductivity of the hydrogel/nano-sized carbon conductive hydrogel proved to be 10% higher than conductive hydrogel without nano-sized carbon. However, it was founded that conductive hydrogels with nano-sized carbon content from 0.5 up to 2.0 wt% were remarkably decreased. This may be due to the non-uniform distribution of nano-sized carbon, resulting from agglomerates of nano-sized carbon. The developed hydrogel is intended for use in the medical and cosmetic fields that is applicable to supply micro-current from device to human body.

  16. The effect of variations in carbon activity on the carburization of austenitic steels in sodium

    International Nuclear Information System (INIS)

    Gwyther, J.R.; Hobdell, M.R.; Hooper, A.J.

    1978-07-01

    Experience has shown that the liquid sodium coolant of fast breeder reactors is an effective carbon-transport medium; the resulting carburization of thin austenitic stainless steel components (eg IHX and fuel cladding) could adversely affect their mechanical integrity. The degree and nature of steel carburization depend, inter alia, on the carbon activity of the sodium environment. Exploratory tests are described in which specimens of austenitic stainless steel were carburized in sodium, the carbon activity of which was continuously monitored by a BNL electrochemical carbon meter. The sodium carbon activity was initially high, but decreased with time, simulating conditions equivalent to plant start-up or coolant clean-up following accidental oil ingress. The extent and nature of steel carburization was identified by metallography, electron microscopy, X-ray crystallography and chemical analysis. (author)

  17. Dissolution of barite for the analysis of strontium isotopes and other chemical and isotopic variations using aqueous sodium carbonate

    Science.gov (United States)

    Breit, G.N.; Simmons, E.C.; Goldhaber, M.B.

    1985-01-01

    A simple procedure for preparing barite samples for chemical and isotopic analysis is described. Sulfate ion, in barite, in the presence of high concentrations of aqueous sodium carbonate, is replaced by carbonate. This replacement forms insoluble carbonates with the cations commonly in barite: Ba, Sr, Ca and Pb. Sulfate is released into the solution by the carbonate replacement and is separated by filtration. The aqueous sulfate can then be reprecipitated for analysis of the sulfur and oxygen isotopes. The cations in the carbonate phase can be dissolved by acidifying the solid residue. Sr can be separated from the solution for Sr isotope analysis by ion-exchange chromatography. The sodium carbonate used contains amounts of Sr which will affect almost all barite 87Sr 86Sr ratios by less than 0.00001 at 1.95?? of the mean. The procedure is preferred over other techniques used for preparing barite samples for the determination of 87Sr 86Sr ratios because it is simple, rapid and enables simultaneous determination of many compositional parameters on the same material. ?? 1985.

  18. Carbon in sodium - A status review of the U.S.A. R and D work

    International Nuclear Information System (INIS)

    McCown, J.J.; Bagnall, C.

    1980-01-01

    Liquid Metal Fast Breeder Reactors contain several types of steel in primary and secondary sodium systems. Austenitic stainless steels are used for in-core components, valves, heat exchangers, tanks and fuel cladding in primary systems. In power generating plants, the secondary or intermediate heat transport system may contain both austenitic and ferritic steel such as 2-1/4 Cr-l Mo type. Sodium circulating throughout the plant contains a number of impurities, metallic and non-metallic, with the steel interstitial elements carbon, hydrogen and oxygen being of prime importance. These elements can affect corrosion rates and mechanical behavior of materials. In the case of carbon, the sodium provides a transport medium with carburization and decarburization occurring in several parts of a system at rates depending upon temperature and types of steel. The US Sodium Technology R and D programs have investigated the behavior, transport, measurement and control of carbon in sodium. Measurement and control methods for carbon-containing materials which might contaminate the plant systems during reactor operation have also been studied. During the early 1970's, several US laboratories were active in studying carbon solubility, activity in sodium and interstitial transfer using both theoretical and experimental approaches. Modelling studies were done and models were used to predict FFTF and CRBRP materials requirements, component design and plant operating conditions. Over the past several years, carbon work has not been heavily emphasized. Most of the R and D studies have centered on improving chemical analysis methods for measuring active carbon, both by on-line monitors and by metal foil equilibration procedures; and on studies of pump oil-sodium reactions, reaction products, temperature effects and oil leak detection methods. One program at General Electric is investigating carburization-decarburization in a ferritic-austenitic system simulating conditions expected in

  19. Carbon in sodium - A status review of the U.S.A. R and D work

    Energy Technology Data Exchange (ETDEWEB)

    McCown, J J; Bagnall, C [HEDL, Richland, WA (United States)

    1980-05-01

    Liquid Metal Fast Breeder Reactors contain several types of steel in primary and secondary sodium systems. Austenitic stainless steels are used for in-core components, valves, heat exchangers, tanks and fuel cladding in primary systems. In power generating plants, the secondary or intermediate heat transport system may contain both austenitic and ferritic steel such as 2-1/4 Cr-l Mo type. Sodium circulating throughout the plant contains a number of impurities, metallic and non-metallic, with the steel interstitial elements carbon, hydrogen and oxygen being of prime importance. These elements can affect corrosion rates and mechanical behavior of materials. In the case of carbon, the sodium provides a transport medium with carburization and decarburization occurring in several parts of a system at rates depending upon temperature and types of steel. The US Sodium Technology R and D programs have investigated the behavior, transport, measurement and control of carbon in sodium. Measurement and control methods for carbon-containing materials which might contaminate the plant systems during reactor operation have also been studied. During the early 1970's, several US laboratories were active in studying carbon solubility, activity in sodium and interstitial transfer using both theoretical and experimental approaches. Modelling studies were done and models were used to predict FFTF and CRBRP materials requirements, component design and plant operating conditions. Over the past several years, carbon work has not been heavily emphasized. Most of the R and D studies have centered on improving chemical analysis methods for measuring active carbon, both by on-line monitors and by metal foil equilibration procedures; and on studies of pump oil-sodium reactions, reaction products, temperature effects and oil leak detection methods. One program at General Electric is investigating carburization-decarburization in a ferritic-austenitic system simulating conditions expected in

  20. Chemical sensors for monitoring non-metallic impurities in liquid sodium coolant

    International Nuclear Information System (INIS)

    Ganesan, Rajesh; Jayaraman, V.; Rajan Babu, S.; Sridharan, R.; Gnanasekaran, T.

    2011-01-01

    Liquid sodium is the coolant of choice for fast breeder reactors. Liquid sodium is highly compatible with structural steels when the concentration of dissolved non-metallic impurities such as oxygen and carbon are low. However, when their concentrations are above certain threshold limits, enhanced corrosion and mass transfer and carburization of the steels would occur. The threshold concentration levels of oxygen in sodium are determined by thermochemical aspects of various ternary oxides of Na-M-O systems (M alloying elements in steels) which take part in corrosion and mass transfer. Dissolved carbon also influences these threshold levels by establishing relevant carbide equilibria. An event of steam leak into sodium at the steam generator, if undetected at its inception itself, can lead to extensive wastage of the tubes of the steam generator and prolonged shutdown. Air ingress into the argon cover gas and leak of hydrocarbon oil used as cooling fluids of the shafts of the centrifugal pumps of sodium are the sources of oxygen and carbon impurities in sodium. Continuous monitoring of the concentration of dissolved hydrogen, carbon and oxygen in sodium coolant will help identifying their ingress at inception itself. An electrochemical hydrogen sensor based on CaHBr-CaBr 2 hydride ion conducting solid electrolyte has been developed for detecting the steam leak during normal operating conditions of the reactor. A nickel diffuser based sensor system using thermal conductivity detector (TCD) and Pd-doped tin oxide thin film sensor has been developed for use during low power operations of the reactor or during its start up. For monitoring carbon in sodium, an electrochemical sensor with molten Na 2 CO 3 -LiCO 3 as the electrolyte and pure graphite as reference electrode has been developed. Yttria Doped Thoria (YDT) electrolyte based oxygen sensor is under development for monitoring dissolved oxygen levels in sodium. Fabrication, assembly, testing and performance of

  1. Characterization of reaction products in sodium-oxygen batteries : An electrolyte concentration study

    OpenAIRE

    Hedman, Jonas

    2017-01-01

    In this thesis, the discharge products formed at the cathode and the performance and cell chemistry of sodium-oxygen batteries have been studied. This was carried out using different NaOTf salt concentrations. The influence of different salt concentrations on sodium-oxygen batteries was investigated since it has been shown that increasing the salt concentration beyond conventional concentrations could result in advantages such as increased stability of the electrolytes towards decomposition, ...

  2. Comparison of the use of sodium carbonate (washing soda crystals) and apomorphine for inducing emesis in dogs.

    Science.gov (United States)

    Yam, E; Hosgood, G; Smart, L

    2016-12-01

    To describe the use of sodium carbonate and apomorphine in a historical cohort of dogs, compare the occurrence of emesis and report any adverse effects recorded. This historical, observational study included information from medical records of dogs that received an emetic agent. The occurrence of emesis with apomorphine or sodium carbonate was calculated and the association between emesis and agent was explored, with the odds ratio and 95% confidence interval (CI) reported. A non-inferiority analysis of the occurrence of emesis for sodium carbonate was performed against an equivalence range of ±7% of the estimated occurrence of emesis with apomorphine. Owners were emailed a short survey about their dog's health after their visit to the hospital for induced emesis. Records for 787 dogs seen from January 2007 to December 2013 were included. For apomorphine, 382/392 dogs showed emesis (97%, 95% CI 95-100%). For sodium carbonate, 320/395 dogs showed emesis (81%, 95% CI 77-85%), which fell below the equivalence range for apomorphine (97 ± 7%, 90-100%) and was considered inferior. The odds ratio of emesis with apomorphine to sodium carbonate was 9.0 (95% CI 4.6-17.6). Of 18 responses to the survey, 5 reported abnormalities after emesis (3 with sodium carbonate, 2 with apomorphine). The occurrence of emesis with sodium carbonate was high but inferior to apomorphine. However, the advantages of sodium carbonate, including less expense and ease of accession compared with apomorphine, make it a viable choice in emergency medicine. © 2016 Australian Veterinary Association.

  3. Morphological alteration, lysosomal membrane fragility and apoptosis of the cells of Indian freshwater sponge exposed to washing soda (sodium carbonate).

    Science.gov (United States)

    Mukherjee, Soumalya; Ray, Mitali; Dutta, Manab Kumar; Acharya, Avanti; Mukhopadhyay, Sandip Kumar; Ray, Sajal

    2015-12-01

    Washing soda is chemically known as sodium carbonate and is a component of laundry detergent. Domestic effluent, drain water and various anthropogenic activities have been identified as major routes of sodium carbonate contamination of the freshwater ecosystem. The freshwater sponge, Eunapius carteri, bears ecological and evolutionary significance and is considered as a bioresource in aquatic ecosystems. The present study involves estimation of morphological damage, lysosomal membrane integrity, activity of phosphatases and apoptosis in the cells of E. carteri under the environmentally realistic concentrations of washing soda. Exposure to washing soda resulted in severe morphological alterations and damages in cells of E. carteri. Fragility and destabilization of lysosomal membranes of E. carteri under the sublethal exposure was indicative to toxin induced physiological stress in sponge. Prolonged exposure to sodium carbonate resulted a reduction in the activity of acid and alkaline phosphatases in the cells of E. carteri. Experimental concentration of 8 mg/l of washing soda for 192 h yielded an increase in the physiological level of cellular apoptosis among the semigranulocytes and granulocytes of E. carteri, which was suggestive to possible shift in apoptosis mediated immunoprotection. The results were indicative of an undesirable shift in the immune status of sponge. Contamination of the freshwater aquifers by washing soda thus poses an alarming ecotoxicological threat to sponges. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Hydrogen substituted graphdiyne as carbon-rich flexible electrode for lithium and sodium ion batteries.

    Science.gov (United States)

    He, Jianjiang; Wang, Ning; Cui, Zili; Du, Huiping; Fu, Lin; Huang, Changshui; Yang, Ze; Shen, Xiangyan; Yi, Yuanping; Tu, Zeyi; Li, Yuliang

    2017-10-27

    Organic electrodes are potential alternatives to current inorganic electrode materials for lithium ion and sodium ion batteries powering portable and wearable electronics, in terms of their mechanical flexibility, function tunability and low cost. However, the low capacity, poor rate performance and rapid capacity degradation impede their practical application. Here, we concentrate on the molecular design for improved conductivity and capacity, and favorable bulk ion transport. Through an in situ cross-coupling reaction of triethynylbenzene on copper foil, the carbon-rich frame hydrogen substituted graphdiyne film is fabricated. The organic film can act as free-standing flexible electrode for both lithium ion and sodium ion batteries, and large reversible capacities of 1050 mAh g -1 for lithium ion batteries and 650 mAh g -1 for sodium ion batteries are achieved. The electrode also shows a superior rate and cycle performances owing to the extended π-conjugated system, and the hierarchical pore bulk with large surface area.

  5. Ultrasonic Assisted Synthesis of Chromenes Catalyzed by Sodium Carbonate in Aqueous Media.

    Science.gov (United States)

    Sabbaghan, Maryam; Sofalgar, Pegah

    2015-01-01

    A simple, efficient, and environmentally benign procedure for the synthesis of 2-amino-4H-chromene ring has been achieved by the three-component reaction of an aromatic aldehyde, malononitrile and diverse enolizable C-H activated compound under ultrasound irradiation using sodium carbonate as a catalyst in aqueous media. Sodium carbonate as a natural salt, being available as an inexpensive catalyst combined with ultrasound method promoted this protocol in comparison to other methods and catalysts.

  6. Influence of sodium carbonate on decomposition of formic acid by pulsed discharge plasma inside bubble in water

    Science.gov (United States)

    Iwabuchi, Masashi; Takahashi, Katsuyuki; Takaki, Koichi; Satta, Naoya

    2016-07-01

    The influence of sodium carbonate on the decomposition of formic acid by discharge inside bubbles in water was investigated experimentally. Oxygen or argon gases were injected into the water through a vertically positioned glass tube, in which the high-voltage wire electrode was placed to generate plasmas at low applied voltage. The concentration of formic acid was determined by ion chromatography. In the case of sodium carbonate additive, the pH increased owing to the decomposition of the formic acid. In the case of oxygen injection, the percentage of conversion of formic acid increased with increasing pH because the reaction rate of ozone with formic acid increased with increasing pH. In the case of argon injection, the percentage of conversion was not affected by the pH owing to the high rate loss of hydroxyl radicals.

  7. Intraerythrocytic sodium and potassium concentrations during acute and chronic digitalization.

    Science.gov (United States)

    Pedersen, K E; Koldkjaer, O; Berndtz, N H; Hvidt, S; Kjaer, K; Midtskov, C; Sanchez, G

    1982-01-01

    To assess the cellular effects of digoxin, intraerythrocytic sodium and potassium concentrations were measured in 17 patients during the early phase of digitalization, in 45 patients on long-term therapy and in 64 non-digitalized control patients. Acute digitalization raised intraerythrocytic sodium from 11.6 +/- 0.4 to 16.7 +/- 1.0 mmol/l (mean +/- SEM) (p less than 0.01) and reduced intraerythrocytic potassium from 100.1 +/- 1.3 to 95.9 +/- 1.8 mmol/l (p less than 0.01). These changes were strongly correlated with the steady-state plasma digoxin concentration. During a few weeks of digoxin therapy, the intraerythrocytic cation composition normalized gradually. In patients on chronic treatment, neither intraerythrocytic sodium (11.3 +/- 0.3 mmol/l) nor potassium concentrations (100.0 +/- 0.6 mmol/l) differed significantly from the values of the control group (11.4 +/- 0.2 and 99.9 +/- 0.5 mmol/l, respectively). The changes in intraerythrocytic cation concentrations, induced by acute digitalization, seem to disappear during chronic administration of the drug.

  8. Carbon coated anatase TiO2 mesocrystals enabling ultrastable and robust sodium storage

    Science.gov (United States)

    Zhang, Weifeng; Lan, Tongbin; Ding, Tianli; Wu, Nae-Lih; Wei, Mingdeng

    2017-08-01

    Nanoporous anatase TiO2 mesocrystals with tunable architectures and crystalline phases were successfully fabricated in the presence of the butyl oleate and oleylamine. Especially, the introduced surfactants served as a carbon source, bring a uniform carbon layer (about 2-8 nm) for heightening the electronic conductivity. The carbon coated TiO2 mesocrystals assembled from crystalline tiny subunits have more space sites for sodium-ion storage. When the material was applied as an electrode material in rechargeable sodium-ion batteries, it exhibited a superior capacity of about 90 mA h g-1 at 20 C (1 C = 168 mA g-1) and a highly reversible capacity for 5000 cycles, which is the longest cycle life reported for sodium storage in TiO2 electrodes.

  9. Nickel adsorption by sodium polyacrylate-grafted activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Ewecharoen, A. [Division of Biotechnology, School of Bioresources and Technology, King Mongkut' s University of Technology Thonburi, 83 Moo 8 Thakham, Bangkhuntien, Bangkok 10150 (Thailand); Thiravetyan, P., E-mail: paitip@hotmail.com [Division of Biotechnology, School of Bioresources and Technology, King Mongkut' s University of Technology Thonburi, 83 Moo 8 Thakham, Bangkhuntien, Bangkok 10150 (Thailand); Wendel, E.; Bertagnolli, H. [Institut fuer Physikalische Chemie, Universitaet Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany)

    2009-11-15

    A novel sodium polyacrylate grafted activated carbon was produced by using gamma radiation to increase the number of functional groups on the surface. After irradiation the capacity for nickel adsorption was studied and found to have increased from 44.1 to 55.7 mg g{sup -1}. X-ray absorption spectroscopy showed that the adsorbed nickel on activated carbon and irradiation-grafted activated carbon was coordinated with 6 oxygen atoms at 2.04-2.06 A. It is proposed that this grafting technique could be applied to other adsorbents to increase the efficiency of metal adsorption.

  10. Efficient lactulose production from cheese whey using sodium carbonate.

    Science.gov (United States)

    Seo, Yeong Hwan; Park, Gwon Woo; Han, Jong-In

    2015-04-15

    An economical method of lactulose production from cheese whey was developed using sodium carbonate (Na2CO3). Three parameters such as temperature, reaction time, and Na2CO3 concentration were identified as experimental factors, and yield was selected as a response parameter. The experimental factors were optimised employing Response Surface Methodology (RSM). Maximum yield of 29.6% was obtained at reaction time of 20.41 min, Na2CO3 of 0.51% at 90 °C. To overcome this limited lactulose yield, due to the conversion of lactulose to galactose, fed batch system was applied using dried cheese whey as lactose source. By this system, limit was broken, and 15.8 g/L of lactulose is produced in hour. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Effects of sodium bicarbonate concentration on growth, photosynthesis, and carbonic anhydrase activity of macroalgae Gracilariopsis lemaneiformis, Gracilaria vermiculophylla, and Gracilaria chouae (Gracilariales, Rhodophyta).

    Science.gov (United States)

    Zhou, Wei; Sui, Zhenghong; Wang, Jinguo; Hu, Yiyi; Kang, Kyoung Ho; Hong, Hye Ran; Niaz, Zeeshan; Wei, Huihui; Du, Qingwei; Peng, Chong; Mi, Ping; Que, Zhou

    2016-06-01

    There is potential for bicarbonate to improve crop yields and economic efficiency of marine algae. However, few studies have focused on the effect of bicarbonate on the growth, photosynthesis, and enzyme activity associated with carbon utilization, especially in commercial macroalgae. Here, the addition of bicarbonate (up to 420 mg L(-1)) to macroalgal cultures has been evaluated for Gracilariopsis lemaneiformis, Gracilaria vermiculophylla, and Gracilaria chouae with respect to growth rate, photosynthetic activity, carbonic anhydrase activity, and biochemical composition. The results showed that the effects of NaHCO3 on growth, chlorophyll a, phycoerythrin, photosynthetic oxygen evolution, photochemical parameters of PSI and PSII, carbonic anhydrase activity, and nitrogen content were significant (P 336 mg L(-1) for Gp. lemaneiformis and >420 mg L(-1) for the other two species). Moreover, species-specific differences induced by supplementation with bicarbonate were discovered during culture. Optimal concentrations of NaHCO3 used in this study were 252 mg L(-1) for Gp. lemaneiformis and 336 mg L(-1) for G. vermiculophylla and G. chouae. These results suggest that an adequate supplementation of sodium bicarbonate is a viable strategy for promoting growth and photosynthetic activity in some macroalgae as well as for improving biochemical composition. The study will help to accelerate the growth rate of algae and improve the quality of thalli, and will also be useful for enhancing the understanding of carbon utilization in macroalgae.

  12. Biological activity and safety of Tripterygium extract prepared by sodium carbonate extraction.

    Science.gov (United States)

    Fang, Wei; Peng, Fan; Yi, Tao; Zhang, Cong; Wan, Chunxi; Xu, Huibi; Lam, Christopher Waikei; Yang, Xiangliang

    2012-09-17

    The commercial preparation named “Tripterygium glycosides” prepared by column chromatography has been used for the treatment of inflammatory and autoimmune diseases with significant efficacy but concurrent toxicity. The aim of this study was to reduce the toxicity of Tripterygium extracts, using cytotoxicity and anti-inflammatory activity of the three principal active components of Tripterygium wilfordii Hook. F. (TWHF)as guiding parameters. Column chromatography was replaced by sodium carbonate extraction for removing the acidic compounds and enriching epoxyditerpenoids and alkaloids in the extract. Results showed that the therapeutic index (IC50/EC50) on murine macrophage Raw 264.7 cells and rat mesangial HBZY-1 cells of the extract prepared by sodium carbonate extraction was significantly higher than that of Tripterygium glycosides(0.8 and 5.2 vs. 0.3 and 2.6, p sodium carbonate extraction may represent a potentially optimal source of medicine with good therapeutic index.

  13. Monitoring and measurement of oxygen concentrations in liquid sodium

    International Nuclear Information System (INIS)

    Smith, D.L.

    1976-01-01

    The measurement of oxygen concentrations in sodium at levels of interest for LMFBR applications is reviewed. Additional data are presented to support the validity of the vanadium-equilibration method as a reference for determination of oxygen concentrations in sodium at levels equal to or less than 15 ppM. Operating experience with electrochemical oxygen meters that have a thoria-yttria electrolyte and a Na--Na 2 O reference electrode is described. Meter lifetimes in excess of one year have generally been achieved for operating temperatures of 352 and 402 0 C, and fairly stable emfs have been observed for periods of several months. 7 fig, 21 references

  14. Spectroscopic and redox properties of curium and californium ions in concentrated aqueous carbonate-bicarbonate media

    International Nuclear Information System (INIS)

    Hobart, D.E.; Varlashkin, P.G.; Samhoun, K.; Haire, R.G.; Peterson, J.R.

    1983-01-01

    Multimilligram quantities of trivalent curium-248 and californium-249 were investigated by absorption spectroscopy, cyclic voltammetry, and bulk solution electrolysis in concentrated aqueous carbonate-bicarbonate solution. Actinide concentrations between 10 -4 and 10 -2 M were studied in 2 M sodium carbonate and 5.5 M potassium carbonate solutions at pH values from 8 to 14. The solution absorption spectra of Cm(III) and Cf(III) in carbonate media are presented for the first time and compared to literature spectra of these species in noncomplexing aqueous solution. It was anticipated that carbonate complexation of the actinide ions could provide a sufficient negative shift in the formal potentials of the M(IV)/M(III) couples of Cm and Cf to permit the generation and stabilization of their tetravalent states in aqueous carbonate-bicarbonate medium. No conclusive evidence was found in the present work to indicate the existence of any higher oxidation states of curium or californium in carbonate solution. Some possible reasons for our inability to generate and detect oxidized species of curium and californium in this medium are discussed

  15. Cementification for radioactive waste including high-concentration sodium sulfate and high-concentration radioactive nuclide

    International Nuclear Information System (INIS)

    Miyamoto, Shinya; Sato, Tatsuaki; Sasoh, Michitaka; Sakurai, Jiro; Takada, Takao

    2005-01-01

    For the cementification of radioactive waste that has large concentrations of sodium sulfate and radioactive nuclide, a way of fixation for sulfate ion was studied comprising the pH control of water in contact with the cement solid, and the removal of the excess water from the cement matrix to prevent hydrogen gas generation with radiolysis. It was confirmed that the sulfate ion concentration in the contacted water with the cement solid is decreased with the formation of ettringite or barium sulfate before solidification, the pH value of the pore water in the cement solid can control less than 12.5 by the application of zeolite and a low-alkali cement such as alumina cement or fly ash mixed cement, and removal of the excess water from the cement matrix by heating is possible with aggregate addition. Consequently, radioactive waste including high-concentration sodium sulfate and high-concentration radioactive nuclide can be solidified with cementitious materials. (author)

  16. Carbon dioxide absorbents containing potassium hydroxide produce much larger concentrations of compound A from sevoflurane in clinical practice.

    Science.gov (United States)

    Yamakage, M; Yamada, S; Chen, X; Iwasaki, S; Tsujiguchi, N; Namiki, A

    2000-07-01

    We investigated the concentrations of degraded sevoflurane Compound A during low-flow anesthesia with four carbon dioxide (CO(2)) absorbents. The concentrations of Compound A, obtained from the inspiratory limb of the circle system, were measured by using a gas chromatograph. In the groups administered 2 L/min fresh gas flow with 1% sevoflurane, when the conventional CO(2) absorbents, Wakolime(TM) (Wako, Tokyo, Japan) and Drägersorb(TM) (Dräger, Lübeck, Germany), were used, the concentrations of Compound A increased steadily from a baseline to 14.3 ppm (mean) and 13.2 ppm, respectively, at 2 h after exposure to sevoflurane. In contrast, when the other novel types of absorbents containing decreased or no potassium hydroxide/sodium hydroxide, Medisorb(TM) (Datex-Ohmeda, Louisville, CO) and Amsorb(TM) (Armstrong, Coleraine, Northern Ireland), were used, Compound A remained at baseline (potassium hydroxide/sodium hydroxide produce much larger concentrations of Compound A from sevoflurane in clinical practice. An absorbent containing neither potassium hydroxide nor sodium hydroxide produces the smallest concentrations of Compound A.

  17. Survey on investigations on carbon chemistry and transfer in sodium

    International Nuclear Information System (INIS)

    Menken, G.; Jung, J.

    1980-01-01

    The operation of Liquid Metal Fast Reactor Systems at elevated temperatures requires the control of carbon impurities in sodium and of carbon transfer related to the metallic structural materials wetted by the coolant. This review is aimed at providing a brief statement of the objectives and accomplishments in some major areas of the investigations on the behaviour of carbon impurities in the heat transfer circuits of the SNR-300 reactor presently under construction at Kalkar on the Rhine

  18. Some observations on the carburization of type 316 stainless steel foil in a low carbon activity sodium environment

    International Nuclear Information System (INIS)

    Thorley, A.W.; Jeffcoat, P.J.

    1982-01-01

    Work currently being undertaken to establish the equilibrium composition of carbides which form in stainless steel foils during their exposure to low carbon activity sodium environment is described. The time it takes the carbon to reach equilibrium during exposure to sodium of different carbon activity is discussed. The lowest carbon activity measureable in test loops where the sodium is just above carburizing to stainless steel is reported. Analytical techniques are used to determine the composition of the carbide and the austenite matrix and hence estimate the carbon activity of the equilibrium structure. This provides a comparison with carbon activity values determined by alternative methods such as the Harwell Carbon Meter and nickel tab techniques

  19. Chemical acceleration of a neutral granulated blast-furnace slag activated by sodium carbonate

    International Nuclear Information System (INIS)

    Kovtun, Maxim; Kearsley, Elsabe P.; Shekhovtsova, Julia

    2015-01-01

    This paper presents results of a study on chemical acceleration of a neutral granulated blast-furnace slag activated using sodium carbonate. As strength development of alkali-activated slag cements containing neutral GBFS and sodium carbonate as activator at room temperature is known to be slow, three accelerators were investigated: sodium hydroxide, ordinary Portland cement and a combination of silica fume and slaked lime. In all cements, the main hydration product is C–(A)–S–H, but its structure varies between tobermorite and riversideite depending on the accelerator used. Calcite and gaylussite are present in all systems and they were formed due to either cation exchange reaction between the slag and the activator, or carbonation. With accelerators, compressive strength up to 15 MPa can be achieved within 24 h in comparison to 2.5 MPa after 48 h for a mix without an accelerator

  20. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Alejandro Lopez-Ortiz; Douglas P. Harrison; Ya Liang

    2001-07-01

    Sodium based sorbents including sodium carbonate may be used to capture carbon dioxide from flue gas. A relatively concentrated carbon dioxide stream may be recoverable for sequestration when the sorbent is regenerated. Electrobalance tests indicated that sodium carbonate monohydrate was formed in a mixture of helium and water vapor at temperatures below 65 C. Additional compounds may also form, but this could not be confirmed. In the presence of carbon dioxide and water vapor, both the initial reaction rate of sodium carbonate with carbon dioxide and water and the sorbent capacity decreased with increasing temperature, consistent with the results from the previous quarter. Increasing the carbon dioxide concentration at constant temperature and water vapor concentration produced a measurable increase in rate, as did increasing the water vapor concentration at constant carbon dioxide concentration and temperature. Runs conducted with a flatter TGA pan resulted in a higher initial reaction rate, presumably due to improved gas-solid contact, but after a short time, there was no significant difference in the rates measured with the different pans. Analyses of kinetic data suggest that the surface of the sodium carbonate particles may be much hotter than the bulk gas due to the highly exothermic reaction with carbon dioxide and water, and that the rate of heat removal from the particle may control the reaction rate. A material and energy balance was developed for a cyclic carbonation/calcination process which captures about 26 percent of the carbon dioxide present in flue gas available at 250 C.

  1. Sodium removal disassembly and examination of the Fermi secondary sodium pump

    International Nuclear Information System (INIS)

    Maffei, H.P.; Funk, C.W.; Ballif, J.L.

    1974-01-01

    The Fermi secondary pump is a centrifugal single stage design. The pump had been operated more than 42,000 hours between 450 and 800 0 F. Sodium was drained from the pump in 1973 and the system was back filled with carbon dioxide. The pump was fabricated for 2.25 Cr-1 Mo Croloy steel. Prior to cleaning the pump was inerted and heated with 150 0 F nitrogen using the pump casing as the containment vessel. The water-vapor-nitrogen process was used in three increasing stages of water concentration. The hydrogen concentration in the discharge line was followed as an indicator of the sodium-water reaction rate. Upon completion of the hydrogen evolution, the pump was rinsed several times with hot water. Six pounds of sodium were removed from the pump during a process cycle of 79 hours including rinsing. The maximum pump temperature recorded was 175 0 F with no variation exceeding 10 0 F. The hydrogen concentration in the effluent provided a very satisfactory index for control of the reaction by adjustment of the water-vapor concentration feed to the system. Rinsing effectiveness was limited by a pool of water in the volute that was not drainable with the available system hook up. Sodium and its compounds were removed from all internal surfaces that could be observed by the first stage of disassembly. All such surfaces were coated with a black deposit. Areas above the sodium liquid level were coated with a vermillion colored oxide. Sodium was found on the (1) threads of the impeller nut lock screw, (2) impeller nut-tapered shaft interface, and (3) vapor deposited sodium was found in the oil seal

  2. Scalable and sustainable synthesis of carbon microspheres via a purification-free strategy for sodium-ion capacitors

    Science.gov (United States)

    Wang, Shijie; Wang, Rutao; Zhang, Yabin; Jin, Dongdong; Zhang, Li

    2018-03-01

    Sodium-based energy storage receives a great deal of interest due to the virtually inexhaustible sodium reserve, while the scalable and sustainable strategies to synthesize carbon-based materials with suitable interlayer spaces and large sodium storage capacities are yet to be fully investigated. Carbon microspheres, with regular geometry, non-graphitic characteristic, and stable nature are promising candidates, yet the synthetic methods are usually complex and energy consuming. In this regard, we report a scalable purification-free strategy to synthesize carbon microspheres directly from 5 species of fresh juice. As-synthesized carbon microspheres exhibit dilated interlayer distance of 0.375 nm and facilitate Na+ uptake and release. For example, such carbon microsphere anodes have a specific capacity of 183.9 mAh g-1 at 50 mA g-1 and exhibit ultra-stability (99.0% capacity retention) after 10000 cycles. Moreover, via facile activation, highly porous carbon microsphere cathodes are fabricated and show much higher energy density at high rate than commercial activated carbon. Coupling the compelling anodes and cathodes above, novel sodium-ion capacitors show the high working potential up to 4.0 V, deliver a maximum energy density of 52.2 Wh kg-1, and exhibit an acceptable capacity retention of 85.7% after 2000 cycles.

  3. Study of new complexes of uranium and comba radical. I.- Complexes defective in sodium carbonate

    International Nuclear Information System (INIS)

    Vera Palomino, J.; Galiano Sedano, J. A.; Parellada Bellod, R.; Bellido Gonzalez, A.

    1975-01-01

    Some complexes formed in presence of defect of sodium carbonate with respect to the stoichiometric ratio (U): (C0 3 ) = 1:3 are studied. This ratio corresponds to the main complex which is responsible for the uranium extraction with CDMBAC organic solutions and from U(VI) aqueous solutions with an excess of sodium carbonate. (Author) 10 refs

  4. JOYO coolant sodium and cover gas purity control database (MK-II core)

    International Nuclear Information System (INIS)

    Ito, Kazuhiro; Nemoto, Masaaki

    2000-03-01

    The experimental fast reactor 'JOYO' served as the MK-II irradiation bed core for testing fuel and material for FBR development for 15 years from 1982 to 1997. During the MK-II operation, impurities concentrations in the sodium and the argon gas were determined by 67 samples of primary sodium, 81 samples of secondary sodium, 75 samples of primary argon gas, 89 samples of secondary argon gas (the overflow tank) and 89 samples of secondary argon gas (the dump tank). The sodium and the argon gas purity control data were accumulated from in thirty-one duty operations, thirteen special test operations and eight annual inspections. These purity control results and related plant data were compiled into database, which were recorded on CD-ROM for user convenience. Purity control data include concentration of oxygen, carbon, hydrogen, nitrogen, chlorine, iron, nickel and chromium in sodium, concentration of oxygen, hydrogen, nitrogen, carbon dioxide, methane and helium in argon gas with the reactor condition. (author)

  5. Studies Conducted of Sodium Carbonate Contaminant Found on the Wing Leading Edge and the Nose Cap of the Space Shuttle Orbiter

    Science.gov (United States)

    Jacobson, Nathan S.; Palou, Jaime J.

    2003-01-01

    In early 2001, three of the space shuttle orbiters were found to have a sodium carbonate contaminant on the wing leading edge and nose cap. These parts are made of a reinforced carbon/carbon material protected by silicon carbide (SiC) and a glass coating. The glass coating is known as Type A and is primarily sodium silicate with particles of SiC. NASA Glenn Research Center's Environmental Durability Branch was asked to determine the chemistry of this deposit formation and assess any possible detrimental effects. At low temperatures, the reverse reaction is favorable. Previous studies of the corrosion of glass show that carbon dioxide in the presence of water does form sodium carbonate on sodium silicate glass (ref. 1). It is quite likely that a similar scenario exists for the orbiter wing leading edge. All three orbiters that formed sodium carbonate were exposed to rain. This formation of sodium carbonate was duplicated in the laboratory. The Type A glass, which coats the wing leading edge and nose cap, was made in a freestanding form and exposed to water in two separate experiments. In one set of experiments, the coating was placed in a petri dish filled with water. As the water evaporated, sodium carbonate formed. In another case, water was slowly dripped on the coating and sodium carbonate formed. The sodium carbonate was detected by chemical analysis and, in some cases, xray diffraction showed a hydrated sodium carbonate. The next step was to examine possible detrimental effects of this sodium carbonate. There are three likely scenarios for the sodium carbonate deposit: (1) it may be removed with a simple rinse, (2) it may remain and flow back into the Type A glass after heating during reentry, or (3) it may remain and flow onto unprotected SiC and/or other parts after heating during reentry. The effect of case 1 is to remove the Na2O constituent from the Type A glass, thus decreasing its effectiveness as a sealant. Even so, overall, it is probably the best

  6. Sodium fire test at broad ranges of temperature and oxygen concentration. 4. Low temperature sodium spray fire tests

    International Nuclear Information System (INIS)

    Kawata, Koji; Miyahara, Shinya

    2005-08-01

    Sodium spray fire tests at the initial sodium temperature of 250degC were conducted under the atmospheric conditions of air and 3% oxygen containing nitrogen to determine the sodium burning rate and the aerosol release fraction and compare them with the test results at the initial sodium temperature of 500degC in air atmosphere. In the tests, sodium was supplied using a commercial spray nozzle into a stainless steel vessel of 100 m 3 volume (SOLFA-2). The sodium burning rate was calculated from two independent methods: the consumption rate of oxygen in the vessel and the enthalpy change of vessel components during the test. The aerosol release fraction was determined from the comparison between the measured aerosol concentrations and the calculated ones by the ABC-INTG code. The main conclusions were as follows, (1) In air atmosphere, a) sodium droplets ignited instantaneously and the spray fire was observed, and b) the sodium burning rate was about 440 g-Na/s and the fraction of supplied sodium was about 70%. (2) In 3% oxygen containing nitrogen, a) ignition of sodium droplets was not observed, and b) the sodium burning rate was about 44 g-Na/s and the fraction of supplied sodium was less than 10%. (author)

  7. Studies on sorption of plutonium on inorganic exchangers from sodium carbonate medium

    Energy Technology Data Exchange (ETDEWEB)

    Pius, I C; Charyulu, M M; Sivaramakrishnan, C K [Fuel Chemistry Division, Bhabha Atomic Research Centre, Mumbai (India); Venkataramani, B [Chemistry Division, Bhabha Atomic Research Centre, Mumbai (India)

    1994-06-01

    Sorption of Pu(IV) from sodium carbonate medium has been investigated by using different inorganic exchangers alumina, silica gel and hydrous titanium oxide. Distribution ratios of Pu(IV) for its sorption on these exchangers from sodium carbonate medium were found to be sufficiently high indicating the suitability of these exchangers for the removal of Pu(IV). The presence of uranium and dibutyl phosphate do not have any effect on distribution ratio. The 10% Pu(IV) breakthrough capacities for above exchangers have been determined with 5 ml bed at a flow rate of 30 ml/hour. (author). 4 refs., 2 tabs.

  8. Sodium and chlorine concentrations in mixed saliva of healthy and cystic fibrosis children

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez-Reyes, M. [Instituto Nacional de Investigaciones Nucleares, Mexico City (Mexico); Sanchez-Aguirre, F.J. [Instituto Mexicano del Seguro Social (Mexico). Dept. de Genetica

    1996-03-01

    Sodium and chlorine concentrations in mixed saliva were simultaneously measured by neutron activation analysis in nine normal children and in nine patients with cystic fibrosis. Sodium levels showed a significant difference (P < 0.01) between patients and controls. The concentration of chlorine was similar in both the control and the cystic fibrosis groups. (author).

  9. Sodium and chlorine concentrations in mixed saliva of healthy and cystic fibrosis children

    International Nuclear Information System (INIS)

    Jimenez-Reyes, M.; Sanchez-Aguirre, F.J.

    1996-01-01

    Sodium and chlorine concentrations in mixed saliva were simultaneously measured by neutron activation analysis in nine normal children and in nine patients with cystic fibrosis. Sodium levels showed a significant difference (P < 0.01) between patients and controls. The concentration of chlorine was similar in both the control and the cystic fibrosis groups. (author)

  10. Thermal Decomposition of Sodium Hydrogen Carbonate and Textural Features of Its Calcines

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Svoboda, Karel; Pohořelý, Michael; Šyc, Michal

    2013-01-01

    Roč. 52, č. 31 (2013), s. 10619-10626 ISSN 0888-5885 R&D Projects: GA MŠk(CZ) 7C11009 Grant - others:RFCS(XE) RFCR-CT-2010-00009 Institutional support: RVO:67985858 Keywords : thermal decomposition * sodium hydrogen carbonate * sodium bicarbonate Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.235, year: 2013

  11. Dehydration of sodium carbonate monohydrate with indirect microwave heating

    International Nuclear Information System (INIS)

    Seyrankaya, Abdullah; Ozalp, Baris

    2006-01-01

    In this study, dehydration of sodium carbonate monohydrate (Na 2 CO 3 .H 2 O) (SCM) in microwave (MW) field with silicon carbide (SiC) as an indirect heating medium was investigated. SCM samples containing up to 3% free moisture were placed in the microwave oven. The heating experiments showed that SCM is a poor microwave energy absorber for up to 6 min of irradiation at an 800 W of microwave power. The heat for SCM calcination is provided by SiC which absorbs microwave. The monohydrate is then converted to anhydrous sodium carbonate on the SiC plate by calcining, i.e. by removing the crystal water through heating of the monohydrate temperatures of over 120 deg. C. The calcination results in a solid phase recrystallization of the monohydrate into anhydrate. In the microwave irradiation process, dehydration of SCM in terms of indirect heating can be accelerated by increasing the microwave field power

  12. Integrated carbon nanospheres arrays as anode materials for boosted sodium ion storage

    Directory of Open Access Journals (Sweden)

    Wangjia Tang

    2018-01-01

    Full Text Available Developing cost-effective advanced carbon anode is critical for innovation of sodium ion batteries. Herein, we develop a powerful combined method for rational synthesis of free-standing binder-free carbon nanospheres arrays via chemical bath plus hydrothermal process. Impressively, carbon spheres with diameters of 150–250 nm are randomly interconnected with each other forming highly porous arrays. Positive advantages including large porosity, high surface and strong mechanical stability are combined in the carbon nanospheres arrays. The obtained carbon nanospheres arrays are tested as anode material for sodium ion batteries (SIBs and deliver a high reversible capacity of 102 mAh g−1 and keep a capacity retention of 95% after 100 cycles at a current density of 0.25 A g−1 and good rate performance (65 mAh g−1 at a high current density of 2 A g−1. The good electrochemical performance is attributed to the stable porous nanosphere structure with fast ion/electron transfer characteristics.

  13. Low-Dimensional Network Formation in Molten Sodium Carbonate.

    Science.gov (United States)

    Wilding, Martin C; Wilson, Mark; Alderman, Oliver L G; Benmore, Chris; Weber, J K R; Parise, John B; Tamalonis, Anthony; Skinner, Lawrie

    2016-04-15

    Molten carbonates are highly inviscid liquids characterized by low melting points and high solubility of rare earth elements and volatile molecules. An understanding of the structure and related properties of these intriguing liquids has been limited to date. We report the results of a study of molten sodium carbonate (Na2CO3) which combines high energy X-ray diffraction, containerless techniques and computer simulation to provide insight into the liquid structure. Total structure factors (F(x)(Q)) are collected on the laser-heated carbonate spheres suspended in flowing gases of varying composition in an aerodynamic levitation furnace. The respective partial structure factor contributions to F(x)(Q) are obtained by performing molecular dynamics simulations treating the carbonate anions as flexible entities. The carbonate liquid structure is found to be heavily temperature-dependent. At low temperatures a low-dimensional carbonate chain network forms, at T = 1100 K for example ~55% of the C atoms form part of a chain. The mean chain lengths decrease as temperature is increased and as the chains become shorter the rotation of the carbonate anions becomes more rapid enhancing the diffusion of Na(+) ions.

  14. Efficacy of systemic diclofenac sodium on intravitreal concentration.

    Science.gov (United States)

    Panahi, Yunes; Naderi, Mostafa; Jadidi, Khosrow; Hoseini, Hadise; Abrishami, Mojtaba

    2018-02-01

    Nonsteroidal anti-inflammatory drugs (NSAIDs), as an alternative, are replacing corticosteroids in ocular inflammatory diseases. Diclofenac has been used mainly topically, and recent focus has been on intravitreal delivery. Both of these methods have been shown to have complications in long-term application. To assess the efficacy of slow release oral diclofenac sodium on intravitreal concentration in experimental model of chemically injured eyes. In an experimental double-masked clinical trial, right eyes of 24 albino rabbits were chemically injured by 1 N NaOH. One hour after chemical injury, 10 cc suspension gavage containing 100 mg slow release diclofenac sodium was administered in all cases. 2, 4, 6, 12, 24, 48 h after gavage, vitreous samples were obtained in all cases. Intravitreal concentration of diclofenac sodium was evaluated in all samples using high-performance liquid chromatography (HPLC) method. Intravitreal diclofenac levels by oral intake were enhanced by the inflammation in all the measurements. In inflamed eyes, diclofenac concentration was ten times more than control eye (2.658 ± 0.344 vs. 0.242 ± 0.0279 and 1.617 ± 0.527 vs. 0.148 ± 0.095; in 2 and 4 h, respectively). After 6 h, diclofenac concentration was statistically different, although it reduced below 1 μg/ml. Diclofenac is delivered to the inflamed eye more than healthy eye. It seems that by oral diclofenac consumption, it is possible to make a significant intravitreal concentration.

  15. Effect of alternative salt use on broiler breast meat yields, tenderness, flavor, and sodium concentration.

    Science.gov (United States)

    Broadway, P R; Behrends, J M; Schilling, M W

    2011-12-01

    Fresh chicken breast fillets were marinated with gourmet-style salts: Himalayan pink salt, Sonoma gourmet salt, sel gus de Guerande, and Bolivian rose salt to evaluate their effects on marination and cook loss yields, tenderness, sensory attributes, and sodium concentration. Fresh chicken breast fillets (48-h postmortem) were vacuum tumbled (137 kPa at 20 rpm for 17 min) in a solution of water, salt, and sodium tripolyphosphate at a level of 20% of the meat weights. Instrumental analyses showed no significant difference (P > 0.05) in meat quality with respect to marination yield, cook yield, or shear-force value. There were also no significant differences (P > 0.05) in sensory descriptors between salt treatments. However, Sonoma gourmet salt showed a tendency (P = 0.0693) to score increased savory note values from panelists, whereas Bolivian rose salt received the lowest score. There were no significant differences (P > 0.05) in sodium concentrations between salt treatments, but numerically, sel gus de Guerande had the lowest sodium concentration, which could be important in producing reduced sodium products. Understanding different salts and sodium concentrations allows the poultry industry to use gourmet salts in products and maintain overall meat quality and flavor.

  16. Comparative study of sodium and potassium in different types of gallstones and in serum of subjects with gallstones and controls

    International Nuclear Information System (INIS)

    Channa, N.A.; Ghanghro, A.B.; Soomro, A.M.

    2008-01-01

    The study comprises evaluation of sodium and potassium in the pathogenesis of human gallstones as well as measurement of the concentration of these elements in gallstones and in sera of 109 gallstone subjects and 100 controls (age and sex matched with no personal or family history of gallstone disease). It was observed that serum concentrations for both sodium and potassium were comparable (p<0.05) between gallstone subjects and control subjects. In gallstones the concentration of sodium was significantly higher as compared to potassium (p<0.5). Normal sodium to potassium ratio was seen in serum of gallstone subject, whereas, low sodium to potassium ratio was seen in gallstone carriers. Amongst the different types of gallstones, significantly high (p<0.05) concentrations of sodium and potassium were seen in calcium bilirubinate gallstones. The levels for these mineral elements were also raised in serum of pure calcium carbonate gallstone subjects. The results demonstrate that the higher concentration of sodium and potassium in gallstones may involve in both calcium bilirubinate gallstones and in serum of calcium carbonate gallstone subjects, which indicate their association with calcium in the precipitation of calcium bilirubinate and calcium carbonate in bile. Furthermore, low sodium to potassium ratio in gallstones indicates low ratio in bile of gallstone subjects. (author)

  17. Comparative Study of Sodium and Potassium in Different Types of Gallstones and in Serum of Subjects with Gallstones and Controls

    Directory of Open Access Journals (Sweden)

    Ali Mohammad Soomro

    2008-06-01

    Full Text Available The study comprises evaluation of sodium and potassium in the pathogenesis of human gallstones as well as measurement of the concentration of these elements in gallstones and in sera of 109 gallstone subjects and 100 controls (age and sex matched with no personal or family history of gallstone disease. It was observed that serum concentrations for both sodium and potassium were comparable (p>0.05 between gallstone subjects and control subjects. In gallstones the concentration of sodium was significantly higher as compared to potassium (p<0.05. Normal sodium to potassium ratio was seen in serum of gallstone subjects, whereas, low sodium to potassium ratio was seen in gallstone carriers. Amongst the different types of gallstones, significantly high (p<0.05 concentrations of sodium and potassium were seen in calcium bilirubinate gallstones. The levels for these mineral elements were also raised in serum of pure calcium carbonate gallstone subjects.The results demonstrate that the higher concentration of sodium and potassium in gallstones may involve in both calcium bilirubinate gallstones and in serum of calcium carbonate gallstone subjects, which indicate their association with calcium in the precipitation of calcium bilirubinate and calcium carbonate in bile. Furthermore, low sodium to potassium ratio in gallstones indicates low ratio in bile of gallstone subjects.

  18. Enrichment of yttrium from rare earth concentrate by ammonium carbonate leaching and peroxide precipitation

    International Nuclear Information System (INIS)

    Vasconcellos, Mari E. de; Rocha, S.M.R. da; Pedreira, W.R.; Queiroz S, Carlos A. da; Abrao, Alcidio

    2006-01-01

    The rare earth elements (REE) solubility with ammonium carbonate vary progressively from element to element, the heavy rare earth elements (HRE) being more soluble than the light rare earth elements (LRE). Their solubility is function of the carbonate concentration and the kind of carbonate as sodium, potassium and ammonium. In this work, it is explored this ability of the carbonate for the dissolution of the REE and an easy separation of yttrium was achieved using the precipitation of the peroxide from complex yttrium carbonate. For this work is used a REE concentrate containing (%) Y 2 O 3 2.4, Dy 2 O 3 0.6, Gd 2 O 3 2.7, CeO 2 2.5, Nd 2 O 3 33.2, La 2 O 3 40.3, Sm 2 O 3 4.1 and Pr 6 O 11 7.5. The mentioned concentrate was produced industrially from the chemical treatment of monazite sand by NUCLEMON in Sao Paulo. The yttrium concentrate was treated with 200 g L -1 ammonium carbonate during 10 and 30 min at room temperature. The experiments indicated that a single leaching operation was sufficient to get a rich yttrium solution with about 60.3% Y 2 O 3 . In a second step, this yttrium solution was treated with an excess of hydrogen peroxide (130 volumes), cerium, praseodymium and neodymium peroxides being completely precipitated and separated from yttrium. Yttrium was recovered from the carbonate solution as the oxalate and finally as oxide. The final product is an 81% Y 2 O 3 . This separation envisages an industrial application. The work discussed the solubility of the REE using ammonium carbonate and the subsequent precipitation of the correspondent peroxides

  19. Proteomic analysis of carbon concentrating chemolithotrophic bacteria Serratia sp. for sequestration of carbon dioxide.

    Science.gov (United States)

    Bharti, Randhir K; Srivastava, Shaili; Thakur, Indu Shekhar

    2014-01-01

    A chemolithotrophic bacterium enriched in the chemostat in presence of sodium bicarbonate as sole carbon source was identified as Serratia sp. by 16S rRNA sequencing. Carbon dioxide sequestering capacity of bacterium was detected by carbonic anhydrase enzyme and ribulose-1, 5- bisphosphate carboxylase/oxygenase (RuBisCO). The purified carbonic anhydrase showed molecular weight of 29 kDa. Molecular weight of RuBisCO was 550 kDa as determined by fast protein liquid chromatography (FPLC), however, sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) showed presence of two subunits whose molecular weights were 56 and 14 kDa. The Western blot analysis of the crude protein and purified sample cross reacted with RuBisCO large-subunit polypeptides antibodies showed strong band pattern at molecular weight around 56 kDa regions. Whole cell soluble proteins of Serratia sp. grown under autotrophic and heterotrophic conditions were resolved by two-dimensional gel electrophoresis and MALDI-TOF/MS for differential expression of proteins. In proteomic analysis of 63 protein spots, 48 spots were significantly up-regulated in the autotrophically grown cells; seven enzymes showed its utilization in autotrophic carbon fixation pathways and other metabolic activities of bacterium including lipid metabolisms indicated sequestration potency of carbon dioxide and production of biomaterials.

  20. Proteomic analysis of carbon concentrating chemolithotrophic bacteria Serratia sp. for sequestration of carbon dioxide.

    Directory of Open Access Journals (Sweden)

    Randhir K Bharti

    Full Text Available A chemolithotrophic bacterium enriched in the chemostat in presence of sodium bicarbonate as sole carbon source was identified as Serratia sp. by 16S rRNA sequencing. Carbon dioxide sequestering capacity of bacterium was detected by carbonic anhydrase enzyme and ribulose-1, 5- bisphosphate carboxylase/oxygenase (RuBisCO. The purified carbonic anhydrase showed molecular weight of 29 kDa. Molecular weight of RuBisCO was 550 kDa as determined by fast protein liquid chromatography (FPLC, however, sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE showed presence of two subunits whose molecular weights were 56 and 14 kDa. The Western blot analysis of the crude protein and purified sample cross reacted with RuBisCO large-subunit polypeptides antibodies showed strong band pattern at molecular weight around 56 kDa regions. Whole cell soluble proteins of Serratia sp. grown under autotrophic and heterotrophic conditions were resolved by two-dimensional gel electrophoresis and MALDI-TOF/MS for differential expression of proteins. In proteomic analysis of 63 protein spots, 48 spots were significantly up-regulated in the autotrophically grown cells; seven enzymes showed its utilization in autotrophic carbon fixation pathways and other metabolic activities of bacterium including lipid metabolisms indicated sequestration potency of carbon dioxide and production of biomaterials.

  1. [Effect of sodium carbonate assisted hydrothermal process on heavy metals stabilization in medical waste incinerator fly ash].

    Science.gov (United States)

    Jin, Jian; Li, Xiao-dong; Chi, Yong; Yan, Jian-hua

    2010-04-01

    A sodium carbonate assisted hydrothermal process was induced to stabilize the fly ash from medical waste incinerator. The results showed that sodium carbonate assisted hydrothermal process reduced the heavy metals leachability of fly ash, and the heavy metal waste water from the process would not be a secondary pollution. The leachability of heavy metals studied in this paper were Cd 1.97 mg/L, Cr 1.56 mg/L, Cu 2.56 mg/L, Mn 17.30 mg/L, Ni 1.65 mg/L, Pb 1.56 mg/L and Zn 189.00 mg/L, and after hydrothermal process with the optimal experimental condition (Na2CO3/fly ash dosage = 5/20, reaction time = 8 h, L/S ratio = 10/1) the leachability reduced to < 0.02 mg/L for Cd, Cr, Cu, Mn, Ni, Pb, and 0.05 mg/L for Zn, according to GB 5085.3-2007. Meanwhile, the concentrations of heavy metals in effluent after hydrothermal process were less than 0.8 mg/L. The heavy metals leachability and concentration in effluent reduced with prolonged reaction time. Prolonged aging can affect the leachability of metals as solids become more crystalline, and heavy metals transferred inside of crystalline. The mechanism of heavy metal stabilization can be concluded to the co precipitation and adsorption effect of aluminosilicates formation, crystallization and aging process.

  2. Interfacial composition and stability of emulsions made with mixtures of commercial sodium caseinate and whey protein concentrate.

    Science.gov (United States)

    Ye, Aiqian

    2008-10-15

    The interfacial composition and the stability of oil-in-water emulsion droplets (30% soya oil, pH 7.0) made with mixtures of sodium caseinate and whey protein concentrate (WPC) (1:1 by protein weight) at various total protein concentrations were examined. The average volume-surface diameter (d32) and the total surface protein concentration of emulsion droplets were similar to those of emulsions made with both sodium caseinate alone and WPC alone. Whey proteins were adsorbed in preference to caseins at low protein concentrations (caseins were adsorbed in preference to whey proteins at high protein concentrations. The creaming stability of the emulsions decreased markedly as the total protein concentration of the system was increased above 2% (sodium caseinate >1%). This was attributed to depletion flocculation caused by the sodium caseinate in these emulsions. Whey proteins did not retard this instability in the emulsions made with mixtures of sodium caseinate and WPC. Copyright © 2008 Elsevier Ltd. All rights reserved.

  3. Carbon-supported cobalt catalyst for hydrogen generation from alkaline sodium borohydride solution

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Dongyan; Liu, Xinmin; Cao, Changqing; Guo, Qingjie [College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Dai, Ping [College of Electromechanical Engineering, Qingdao University of Science and Technology, Qingdao 266061 (China)

    2008-08-01

    Low cost transition metal catalysts with high performance are attractive for the development of on-board hydrogen generation systems by catalytic hydrolysis of sodium borohydride (NaBH{sub 4}) in fuel cell fields. In this study, hydrogen production from alkaline NaBH{sub 4} via hydrolysis process over carbon-supported cobalt catalysts was studied. The catalytic activity of the supported cobalt catalyst was found to be highly dependent on the calcination temperatures. The hydrogen generation rate increases with calcination temperatures in the range of 200-400 C, but a high calcination temperature above 500 C led to markedly decreased activity. X-ray diffraction patterns reveal that the catalysts experience phase transition from amorphous Co-B to crystalline cobalt hydroxide with increase in calcination temperatures. The reaction performance is also dependent on the concentration of NaBH{sub 4}, and the hydrogen generation rate increases for lower NaBH{sub 4} concentrations and decreases after reaching a maximum at 10 wt.% of NaBH{sub 4}. (author)

  4. Kinetics of sodium borohydride direct oxidation and oxygen reduction in sodium hydroxide electrolyte

    International Nuclear Information System (INIS)

    Chatenet, Marian; Micoud, Fabrice; Roche, Ivan; Chainet, Eric

    2006-01-01

    The direct oxidation of sodium borohydride in concentrated sodium hydroxide medium has been studied by cyclic and linear voltammetry, chronoamperometry and chronopotentiometry for silver and gold electrocatalysts, either bulk and polycrystalline or nanodispersed over high area carbon blacks. Gold and silver yield rather complete utilisation of the reducer: around 7.5 electrons are delivered on these materials, versus 4 at the most for platinum as a result of the BH 4 - non-negligible hydrolysis taking place on this latter material. The kinetic parameters for the direct borohydride oxidation are better for gold than for silver. A strong influence of the ratio of sodium hydroxide versus sodium borohydride is found: whereas the theoretical stoichiometry does forecast that eight hydroxide ions are needed for each borohydride ion, our experimental results prove that a larger excess hydroxide ion is necessary in quasi-steady state conditions. When the above-mentioned ratio is unity (1 M NaOH and 1 M NaBH 4 ), the tetrahydroborate ions direct oxidation is limited by the hydroxide concentration, and their hydrolysis is no longer negligible. The hydrolysis products are probably BH 3 OH - ions, for which gold displays a rather good oxidation activity. Additionally, silver, which is a weak BH 4 - oxidation electrocatalyst, exhibits the best activity of all the studied materials towards the BH 3 OH - direct oxidation. Finally, carbon-supported gold nanoparticles seem promising as anode material to be used in direct borohydride fuel cells

  5. EFFECT OF SODIUM HYDROXIDE CONCENTRATION ON FRESH PROPERTIES AND COMPRESSIVE STRENGTH OF SELF-COMPACTING GEOPOLYMER CONCRETE

    Directory of Open Access Journals (Sweden)

    FAREED AHMED MEMON

    2013-02-01

    Full Text Available This paper reports the results of the laboratory tests conducted to investigate the effect of sodium hydroxide concentration on the fresh properties and compressive strength of self-compacting geopolymer concrete (SCGC. The experiments were conducted by varying the concentration of sodium hydroxide from 8 M to 14 M. Test methods such as Slump flow, V-Funnel, L-box and J-Ring were used to assess the workability characteristics of SCGC. The test specimens were cured at 70°C for a period of 48 hours and then kept in room temperature until the day of testing. Compressive strength test was carried out at the ages of 1, 3, 7 and 28 days. Test results indicate that concentration variation of sodium hydroxide had least effect on the fresh properties of SCGC. With the increase in sodium hydroxide concentration, the workability of fresh concrete was slightly reduced; however, the corresponding compressive strength was increased. Concrete samples with sodium hydroxide concentration of 12 M produced maximum compressive strength.

  6. Water leak detection in sodium heated steam generators through measurement of hydrogen concentration in sodium

    International Nuclear Information System (INIS)

    Cambillard, E.; Lacroix, A.; Martin, P.; Viala, J.

    1980-07-01

    This report includes a description of apparatus for measuring hydrogen concentration in the secondary sodium system of the PHENIX reactor. The calibration method and results obtained since the commissioning of the reactor are also described. Mention is made of improvements to be built into SUPER PHENIX [fr

  7. Influences of sodium carbonate on physicochemical properties of lansoprazole in designed multiple coating pellets.

    Science.gov (United States)

    He, Wei; Yang, Min; Fan, Jun Hong; Feng, Cai Xia; Zhang, Su Juan; Wang, Jin Xu; Guan, Pei Pei; Wu, Wei

    2010-09-01

    Lansoprazole (LSP), a proton-pump inhibitor, belongs to class II drug. It is especially instable to heat, light, and acidic media, indicating that fabrication of a formulation stabilizing the drug is difficult. The addition of alkaline stabilizer is the most powerful method to protect the drug in solid formulations under detrimental environment. The purpose of the study was to characterize the designed multiple coating pellets of LSP containing an alkaline stabilizer (sodium carbonate) and assess the effect of the stabilizer on the physicochemical properties of the drug. The coated pellets were prepared by layer-layer film coating with a fluid-bed coater. In vitro release and acid-resistance studies were carried out in simulated gastric fluid and simulated intestinal fluid, respectively. Furthermore, the moisture-uptake test was performed to evaluate the influence of sodium carbonate on the drug stability. The results indicate that the drug exists in the amorphous state or small (nanometer size) particles without crystallization even after storage at 40°C/75% for 5 months. The addition of sodium carbonate to the pellet protects the drug from degradation in simulated gastric fluid in a dose-dependent manner. The moisture absorbed into the pellets has a detrimental effect on the drug stability. The extent of drug degradation is directly correlated with the content of moisture absorption. In conclusion, these results suggest that the presence of sodium carbonate influence the physicochemical properties of LSP, and the designed multiple coating pellets enhance the drug stability.

  8. THE STIMULATING EFFECT OF LASER RED LIGHT, FAR RED LIGHT AND SODIUM CARBONATE AT THE INITIAL STAGES OF BARLEY ONTOGENESIS

    Directory of Open Access Journals (Sweden)

    G. P. Dudin

    2014-01-01

    Full Text Available Summary. Modern ecological state of the environment and human unhealthy diet cause many diseases. A healthy diet is the one that contains adequate amounts of proteins, fats, carbohydrates, vitamins, macronutrients and micronutrients. Photosynthesis i. e. the process by which plants produce organic compounds from carbon dioxide and water, is the source of life, the source of evolution and proliferation of life forms on the Earth. Thus, the juice made from sprouted barley provides physiologically active chlorophyll, macronutrients and micronutrients, vitamins А, В2 , В3 , В5 , В6 , В8 , Е and К. It is well known that light from a red laser with a wavelength of 638.2 nm has a stimulating action on the germination energy, germination ability and productivity of seeds, and on the crop yields. Therefore, this research is of primary importance today. The research result produced a sharp decline in plant vigor and germinating capacity of barley when soaking in 1n sodium carbonate solution, as well as changes in the ratio of potassium-sodium balance in plants. Thus at lower concentrations of sodium carbonate and 0.1 n sodium increasing of pigment content in barley is observed on the seventh day. The red laser light has a similar stimulating action: the chlorophyll content of barley plants increased after the red laser treatment of barley seeds. However, the chlorophyll contents were depressed when the seeds were exposed to far red light with wavelengths of 754±10 nm. Using these factors, one can manage the content of chlorophyll and sodium-potassium balance in the initial stages of barley ontogenesis in the technology of barley juice or the powder for a healthy and proper human diet.

  9. Structure and polymer form of poly-3-hydroxyalkanoates produced by Pseudomonas oleovorans grown with mixture of sodium octanoate/undecylenic acid and sodium octanoate/5-phenylvaleric acid.

    Science.gov (United States)

    Ho, I-Ching; Yang, Sheng-Pin; Chiu, Wen-Yen; Huang, Shih-Yow

    2007-01-30

    PHAs (poly-3-hydroxyalkanoates) obtained by Pseudomonas oleovorans grown with mixed carbon sources were investigated. Mixed carbon sources were sodium octanoate/undecylenic acid and sodium octanoate/5-phenylvaleric acid. Effect of carbon source in pre-culture on PHAs structure was investigated. Main fermentation was conducted with mixture of sodium octanoate/undecylenic acid, and PHA contained both saturated and unsaturated units. When more undecylenic acid was used in the medium, the ratio of unsaturated unit increased and the T(g) of the products also changed. The PHA grown with mixture of sodium octanoate and undecylenic acid was a random copolymer, which was determined by DSC analysis. Using mixed carbon sources of sodium octanoate and 5-phenylvaleric acid, highest dry cell weight and PHA concentration were obtained when 0.02g or 0.04g of 5-phenylvaleric acid were added in 50mL medium. Cultured with sodium octanoate and 5-phenylvaleric acid, PHA containing HO (3-hydroxyoctanoate) unit and HPV (3-hydroxy-5-phenylvalerate) unit was produced. T(g) of the products fell between those of pure PHO and pure PHPV. By means of DSC analysis and fractionation method, the PHA obtained was regarded as a random copolymer.

  10. X-ray Absorption Spectroscopy Identifies Calcium-Uranyl-Carbonate Complexes at Environmental Concentrations

    International Nuclear Information System (INIS)

    Kelly, Shelly D.; Kemner, Kenneth M.; Brooks, Scott C.

    2007-01-01

    Current research on bioremediation of uranium-contaminated groundwater focuses on supplying indigenous metal-reducing bacteria with the appropriate metabolic requirements to induce microbiological reduction of soluble uranium(VI) to poorly soluble uranium(IV). Recent studies of uranium(VI) bioreduction in the presence of environmentally relevant levels of calcium revealed limited and slowed uranium(VI) reduction and the formation of a Ca-UO2-CO3 complex. However, the stoichiometry of the complex is poorly defined and may be complicated by the presence of a Na-UO2-CO3 complex. Such a complex might exist even at high calcium concentrations, as some UO2-CO3 complexes will still be present. The number of calcium and/or sodium atoms coordinated to a uranyl carbonate complex will determine the net charge of the complex. Such a change in aqueous speciation of uranium(VI) in calcareous groundwater may affect the fate and transport properties of uranium. In this paper, we present the results from X-ray absorption fine structure (XAFS) measurements of a series of solutions containing 50 lM uranium(VI) and 30 mM sodium bicarbonate, with various calcium concentrations of 0-5 mM. Use of the data series reduces the uncertainty in the number of calcium atoms bound to the UO2-CO3 complex to approximately 0.6 and enables spectroscopic identification of the Na-UO2-CO3 complex. At nearly neutral pH values, the numbers of sodium and calcium atoms bound to the uranyl triscarbonate species are found to depend on the calcium concentration, as predicted by speciation calculations

  11. Recent Progress in Design of Biomass-Derived Hard Carbons for Sodium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Joanna Górka

    2016-12-01

    Full Text Available Sodium ion batteries (SIBs have attracted lots of attention over last few years due to the abundance and wide availability of sodium resources, making SIBs the most cost-effective alternative to the currently used lithium ion batteries (LIBs. Many efforts are underway to find effective anodes for SIBs since the commercial anode for LIBs, graphite, has shown very limited capacity for SIBs. Among many different types of carbons, hard carbons—especially these derived from biomass—hold a great deal of promise for SIB technology thanks to their constantly improving performance and low cost. The main scope of this mini-review is to present current progress in preparation of negative electrodes from biomass including aspects related to precursor types used and their impact on the final carbon characteristics (structure, texture and composition. Another aspect discussed is how certain macro- and microstructure characteristics of the materials translate to their performance as anode for Na-ion batteries. In the last part, current understanding of factors governing sodium insertion into hard carbons is summarized, specifically those that could help solve existing performance bottlenecks such as irreversible capacity, initial low Coulombic efficiency and poor rate performance.

  12. Fluoroethylene Carbonate-Based Electrolyte with 1 M Sodium Bis(fluorosulfonyl)imide Enables High-Performance Sodium Metal Electrodes.

    Science.gov (United States)

    Lee, Yongwon; Lee, Jaegi; Lee, Jeongmin; Kim, Koeun; Cha, Aming; Kang, Sujin; Wi, Taeung; Kang, Seok Ju; Lee, Hyun-Wook; Choi, Nam-Soon

    2018-05-02

    Sodium (Na) metal anodes with stable electrochemical cycling have attracted widespread attention because of their highest specific capacity and lowest potential among anode materials for Na batteries. The main challenges associated with Na metal anodes are dendritic formation and the low density of deposited Na during electrochemical plating. Here, we demonstrate a fluoroethylene carbonate (FEC)-based electrolyte with 1 M sodium bis(fluorosulfonyl)imide (NaFSI) salt for the stable and dense deposition of the Na metal during electrochemical cycling. The novel electrolyte combination developed here circumvents the dendritic Na deposition that is one of the primary concerns for battery safety and constructs the uniform ionic interlayer achieving highly reversible Na plating/stripping reactions. The FEC-NaFSI constructs the mechanically strong and ion-permeable interlayer containing NaF and ionic compounds such as Na 2 CO 3 and sodium alkylcarbonates.

  13. Sodium fluxes in sweet pepper exposed to varying sodium concentrations

    NARCIS (Netherlands)

    Blom-Zandstra, M.; Vogelzang, S.A.; Veen, B.W.

    1998-01-01

    The sodium transport and distribution of sweet pepper (Capsicum annuum L.) under saline conditions were studied after transferring the plants to a sodium-free nutrient solution. Sodium stress up to 60 mM did not affect the growth of sweet pepper, as it appears able to counteract the unfavourable

  14. Glycolysis of carbon fiber-epoxy unidirectional mat catalysed by sodium hydroxide

    Science.gov (United States)

    Zaini, Mariana Binti Mohd; Badri, Khairiah Haji

    2014-09-01

    This study was conducted to recycle carbon fibre-epoxy (CFRP) composite in woven sheet/ mat form. The CFRP was recycled through glycolysis with polyethlyene glycol (PEG 200) as the solvent. The CFRP was loaded into the solvent at a ratio of 4:1 (w/w). PEG200 was diluted with water to a ratio of 80:20 (v/v). This reaction was catalysed by sodium hydroxide (NaOH) solution with varying concentrations at 1.5, 1.7 and 1.9% (w/v). The glycolysis was conducted at 180-190 °C. The recovered CF (rCF) was analysed using Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray (EDX) while the degraded solution was analysed using FTIR and the epoxy content was determined. The FTIR spectrum of the rCF exhibited the disappearance of the COC peak belonged to epoxy and supported by the SEM micrographs that showed clear rCF. On the other hand, the analysed filtrate detected the disappearance of oxygen peak element in the EDX spectrum for all rCF samples. This gave an indication that the epoxy resin has been removed from the surface of the carbon fiber.

  15. Glycolysis of carbon fiber-epoxy unidirectional mat catalysed by sodium hydroxide

    Energy Technology Data Exchange (ETDEWEB)

    Zaini, Mariana Binti Mohd [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Badri, Khairiah Haji [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia and Polymer Research Center, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43 (Malaysia)

    2014-09-03

    This study was conducted to recycle carbon fibre-epoxy (CFRP) composite in woven sheet/ mat form. The CFRP was recycled through glycolysis with polyethlyene glycol (PEG 200) as the solvent. The CFRP was loaded into the solvent at a ratio of 4:1 (w/w). PEG200 was diluted with water to a ratio of 80:20 (v/v). This reaction was catalysed by sodium hydroxide (NaOH) solution with varying concentrations at 1.5, 1.7 and 1.9% (w/v). The glycolysis was conducted at 180-190 °C. The recovered CF (rCF) was analysed using Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray (EDX) while the degraded solution was analysed using FTIR and the epoxy content was determined. The FTIR spectrum of the rCF exhibited the disappearance of the COC peak belonged to epoxy and supported by the SEM micrographs that showed clear rCF. On the other hand, the analysed filtrate detected the disappearance of oxygen peak element in the EDX spectrum for all rCF samples. This gave an indication that the epoxy resin has been removed from the surface of the carbon fiber.

  16. Geographic distribution of soluble salts, exchangeable sodium and calcium carbonate in the Caribbean Region of Colombia

    International Nuclear Information System (INIS)

    Pulido, Carlos E

    2000-01-01

    A research was carried out to establish the distribution of soluble salts, exchangeable sodium and calcium carbonate in the soils of the Caribbean Region. The results show that 28,3% (3.506.033 ha) of the soils have problems related to salinity. The soils of the arid and semiarid zones and those belonging to the sea plain are affected severely by soluble salts, exchangeable sodium and calcium carbonate

  17. Enhanced gelation of chitosan/β-sodium glycerophosphate thermosensitive hydrogel with sodium bicarbonate and biocompatibility evaluated.

    Science.gov (United States)

    Deng, Aipeng; Kang, Xi; Zhang, Jing; Yang, Yang; Yang, Shulin

    2017-09-01

    The application of chitosan/β-sodium glycerophosphate (β-GP) thermosensitive hydrogel has been limited by the relatively slow gelation, weak mechanical resistance and poor cytocompatibility. In this study, sodium hydrogen carbonate (NaHCO 3 ) was applied with β-GP as gel agents to produce high-strength hydrogel. The hydrogels prepared with high NaHCO 3 concentration or more gel agents showed shorter gelation time, better thermostability, drastically enhanced resistance in compression. Meanwhile, the hydrogels presented obvious porous structures and excellent biocompatibility to HUVEC and NIH 3T3 cultured in vitro with higher NaHCO 3 concentration and moderate concentration of β-GP. Overall, appropriate concentration of β-GP combined with NaHCO 3 can be a good gel regent to improve properties of chitosan thermosensitive hydrogels. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. The effect of sodium bicarbonate and validation of beckman coulter AU680 analyzers for measuring total carbon dioxide (TCO2) concentrations in horse serum.

    Science.gov (United States)

    Dirikolu, Levent; Waller, Pamela; Waguespack, Mona Landry; Andrews, Frank Michael; Keowen, Michael Layne; Gaunt, Stephen David

    2017-11-01

    This study evaluated the usage of Beckman Coulter AU680 analyzers for measurement of TCO 2 in horse serum, and the effect of sodium bicarbonate administrations on serum TCO 2 levels in resting horses. Treatment of horses with sodium bicarbonate did not result in any adverse events. Mean TCO 2 concentration was significantly higher from 1 to 8 h in the sodium bicarbonate-treated horses compared to the untreated controls. Within an hour, administration of sodium bicarbonate increased the TCO 2 level from 31.5 ± -2.5 (SD) to 34.0 ± 2.65 (SD) mmol/L and at 2-8 h post-administration, the TCO 2 level was above the 36 mmol/L cut-off level. In all quality control analysis of Australian standard by Beckman Coulter AU680 analyzer, the instrument slightly over estimated the TCO 2 level but the values were in close agreement with mean TCO 2 level being 38.03 with ± 0.87 mmol/L (SD). Expanded uncertainty was calculated using different levels of confidence interval. Based on 99.5% confidence interval using 0.805% expanded uncertainty using mean measured concentration of 38.05 mmol/L, it was estimated that any race samples TCO 2 level higher than 38.5 mmol/L will be indicative of sodium bicarbonate administration using Beckman Coulter AU680 analyzer in Louisiana.

  19. Dietary Sodium Modifies Serum Uric Acid Concentrations in Humans.

    Science.gov (United States)

    Todd, Alwyn S; Walker, Robert J; MacGinley, Robert J; Kelly, Jaimon; Merriman, Tony R; Major, Tanya J; Johnson, Richard J

    2017-11-06

    Subjects with hypertension are frequently obese or insulin resistant, both conditions in which hyperuricemia is common. Obese and insulin-resistant subjects are also known to have blood pressure that is more sensitive to changes in dietary sodium intake. Whether hyperuricemia is a resulting consequence, moderating or contributing factor to the development of hypertension has not been fully evaluated and very few studies have reported interactions between sodium intake and serum uric acid. We performed further analysis of our randomized controlled clinical trials (Australian New Zealand Clinical Trials Registry #12609000161224 and #12609000292279) designed to assess the effects of modifying sodium intake on concentrations of serum markers, including uric acid. Uric acid and other variables (including blood pressure, renin, and aldosterone) were measured at baseline and 4 weeks following the commencement of low (60 mmol/day), moderate (150 mmol/day), and high (200-250 mmol/day) dietary sodium intake. The median aldosterone-to-renin ratio was 1.90 [pg/ml]/[pg/ml] (range 0.10-11.04). Serum uric acid fell significantly in both the moderate and high interventions compared to the low sodium intervention. This pattern of response occurred when all subjects were analyzed, and when normotensive or hypertensive subjects were analyzed alone. Although previously reported in hypertensive subjects, these data provide evidence in normotensive subjects of an interaction between dietary sodium intake and serum uric acid. As this interaction is present in the absence of hypertension, it is possible it could play a role in hypertension development, and will need to be considered in future trials of dietary sodium intake. The trials were registered with the Australian and New Zealand Clinical Trials Registry as ACTRN12609000161224 and ACTRN1260. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  20. Relationship between plasma growth hormone concentration and cellular sodium transport in acromegaly

    Energy Technology Data Exchange (ETDEWEB)

    Herlitz, H.; Jonsson, O.; Bengtsson, B.-Aa. (Departments of Nephrology, Urology and Endocrinology, University of Goeteborg, Goeteborg (Sweden))

    1992-01-01

    We investigated the relationship between mean plasma growth hormone (GH) concentration and cellular sodium transport in untreated and treated acromegaly. Seventeen patients (age 55 [+-] 3 years) with active acromegaly were studied with respect to plasma GH (mean of 24 h GH profile) and erythrocyte electrolyte content as well as transmembrane sodium transport. The patients were reinvestigated two weeks after successful surgery (N = 14) and again after one year (N = 13). Erythrocyte electrolytes were analyzed by flame photometry and sodium influx and efflux rate constant determined by in vitro incubation using a modified Keyne's formula. In patients with active acromegaly there was a significant positive correlation between IGF-1 and cellular sodium transport, while GH tended to show a negative relatonship to the same parameter. After successful treatment, both IGF-1 and GH disclosed a positive relationship to cellular sodium transport. After one year, a significant increase in erythrocyte sodium content was seen in the patients compared to the preoperative situation. In conclusion, if this is a generalized phenomonen the results are compatible with a sodium-retaining effect of GH via stimulation of transmembrane sodium transport. In active acromegaly this may be counteracted by a sodium transport inhibitor giving the reverse relationship between GH and cellular sodium transport. (au).

  1. Sodium carbonate activated slag as cement replacement in autoclaved aerated concrete

    NARCIS (Netherlands)

    Yuan, B.; Straub, C.; Segers, S.; Yu, Q.; Brouwers, H.J.H.

    2017-01-01

    This paper aims to study the suitability of fully replacing cement by sodium carbonate activated slag in producing autoclaved aerated concrete (AAC). The material properties of the product are characterized in terms of green strength development, mechanical properties, pore related properties such

  2. Long-term sodium chloride retention in a rural watershed: legacy effects of road salt on streamwater concentration.

    Science.gov (United States)

    Kelly, Victoria R; Lovett, Gary M; Weathers, Kathleen C; Findlay, Stuart E G; Strayer, David L; Burns, David I; Likens, Gene E

    2008-01-15

    Sodium and chloride concentrations and export increased from 1986 to 2005 in a rural stream in southeastern New York. Concentrations increased 1.5 mg/L per year (chloride) and 0.9 mg/L per year (sodium), and export increased 33,000 kg/year (chloride) and 20,000 kg/year (sodium) during this period. We estimate that salt used for deicing accounted for 91% of the sodium chloride input to the watershed, while sewage and water softeners accounted for less than 10% of the input. Road salt use in the watershed did not increase during the study, but sodium and chloride from sewage and water softeners is likely to have increased slightly due to a small increase in population. Increased input from sewage and water softeners cannot account for the increase in concentration and export from the watershed. Model results suggest that the increase in streamwater concentration and export was likely due to a lag effect of long-term road salt use and subsurface buildup.

  3. Dynamical analysis on carbon transfer in liquid metal cooled fast breeder reactor

    International Nuclear Information System (INIS)

    Kataoka, Tadayuki; Matsumoto, Keishi

    1979-01-01

    The dynamical analysis was undertaken on the exchange of carbon taking place between the structural steels and sodium for the case of a bi-metallic secondary system constituted of type 304 stainless and 2 1/4Cr-1Mo steels, representing the secondary system of a liquid sodium cooled fast breeder reactor. The analysis brought to light the effects to be expected on the long terms carbon transfer behavior of: (a) the surface areas of structural steels in contact with flowing sodium, (b) the thickness of the sodium-boundary layer, (c) the initial carbon concentration in the sodium, and (d) the rate of carbon contamination of the sodium. (author)

  4. Na-ion capacitor using sodium pre-doped hard carbon and activated carbon

    International Nuclear Information System (INIS)

    Kuratani, Kentaro; Yao, Masaru; Senoh, Hiroshi; Takeichi, Nobuhiko; Sakai, Tetsuo; Kiyobayashi, Tetsu

    2012-01-01

    We assembled a sodium-ion capacitor (Na-IC) by combining sodium pre-doped hard carbon (HC) as the negative- and activated carbon (AC) as the positive-electrode. The electrochemical properties were compared with two lithium-ion capacitors (Li-ICs) in which the negative electrodes were prepared with Li pre-doped HC and mesocarbon microbeads (MCMB). The positive and negative electrodes were prepared using the established doctor blade method. The negative electrodes were galvanostatically pre-doped with Na or Li to 80% of the full capacity of carbons. The potential of the negative electrodes after pre-doping was around 0.0 V vs. Na/Na + or Li/Li + , which resulted in the higher output potential difference of the Na-IC and Li-ICs than that of the conventional electrochemical double-layer capacitors (EDLCs) because AC positive electrode works in the same principle both in the ion capacitors and in the EDLC. The state-of-charge of the negative electrode varied 80 ± 10% during the electrochemical charging and discharging. The capacity of the cell was evaluated using galvanostatic charge–discharge measurement. At the discharge current density of 10 mA cm −2 , the Na-IC maintained 70% of the capacity that obtained at the current density of 0.5 mA cm −2 , which was comparable to the Li-ICs. At 50 mA cm −2 , the capacities of the Li-IC(MCMB) and the Na-IC dropped to 20% whereas the Li-IC(HC) retained 30% of the capacity observed at 0.5 mA cm −2 . The capacities of the Na-IC and Li-ICs decreased by 9% and 3%, respectively, after 1000 cycles of charging and discharging.

  5. Preparation of Carbon-Chitosan-Polyvinyl Chloride (CC-PVC) Material and its Application to Electrochemical Degradation of Methylene Blue in Sodium Chloride Solution

    Science.gov (United States)

    Riyanto; Prawidha, A. D.

    2018-01-01

    Electrochemical degradation of methylene blue using Carbon-Chitosan-Polyvinyl Chloride (CC-PVC) electrode in sodium chloride have been done. The aim of this work was to degradation of methylene blue using Carbon-Chitosan-Polyvinyl Chloride (CC-PVC). Carbon chitosan composite electrode was preparing by Carbon and Chitosan powder and PVC in 4 mL tetrahydrofuran (THF) solvent and swirled flatly to homogeneous followed by drying in an oven at 100 °C for 3 h. The mixture was placed in stainless steel mould and pressed at 10 ton/cm2. Sodium chloride was used electrolyte solution. The effects of the current and electrolysis time were investigated using spectrophotometer UV-Visible. The experimental results showed that the carbon-chitosan composite electrode have higher effect in the electrochemical degradation of methylene blue in sodium chloride. Based on UV-visible spectra analysis shows current and electrolysis time has high effect to degradation of methylene blue in sodium chloride. Chitosan and polyvinyl chloride can strengthen the bond between the carbons so that the material has the high stability and conductivity. As conclusions is Carbon-Chitosan-Polyvinyl Chloride (CC-PVC) electrode have a high electrochemical activity for degradation of methylene blue in sodium chloride.

  6. Rubber-based carbon electrode materials derived from dumped tires for efficient sodium-ion storage.

    Science.gov (United States)

    Wu, Zhen-Yue; Ma, Chao; Bai, Yu-Lin; Liu, Yu-Si; Wang, Shi-Feng; Wei, Xiao; Wang, Kai-Xue; Chen, Jie-Sheng

    2018-04-03

    The development of sustainable and low cost electrode materials for sodium-ion batteries has attracted considerable attention. In this work, a carbon composite material decorated with in situ generated ZnS nanoparticles has been prepared via a simple pyrolysis of the rubber powder from dumped tires. Upon being used as an anode material for sodium-ion batteries, the carbon composite shows a high reversible capacity and rate capability. A capacity as high as 267 mA h g-1 is still retained after 100 cycles at a current density of 50 mA g-1. The well dispersed ZnS nanoparticles in carbon significantly enhance the electrochemical performance. The carbon composites derived from the rubber powder are proposed as promising electrode materials for low-cost, large-scale energy storage devices. This work provides a new and effective method for the reuse of dumped tires, contributing to the recycling of valuable waste resources.

  7. Clinical findings and effect of sodium hydrogen carbonate in patients with glutathione synthetase deficiency.

    Science.gov (United States)

    Gündüz, Mehmet; Ünal, Özlem; Kavurt, Sumru; Türk, Emrecan; Mungan, Neslihan Önenli

    2016-04-01

    Glutathione synthetase (GS) deficiency is a rare inborn error of glutathione (GSH) metabolism manifested by severe metabolic acidosis, hemolytic anemia, neurological problems and massive excretion of pyroglutamic acid (5-oxoproline) in the urine. The disorder has mild, moderate, and severe clinical variants. We aimed to report clinical and laboratory findings of four patients, effect of sodium hydrogen carbonate treatment and long-term follow up of three patients. Urine organic acid analysis was performed with gas chromatography-mass spectrometry. Molecular genetic analysis was performed in three patients, mutation was found in two of them. Enzyme analysis was performed in one patient. Clinical and laboratory findings of four patients were evaluated. One patient died at 4 months old, one patient's growth and development are normal, two patients have developed intellectual disability and seizures in the long term follow up period. Three patients benefited from sodium hydrogen carbonate treatment. The clinical picture varies from patient to patient, so it is difficult to predict the prognosis and the effectiveness of treatment protocols. We reported long term follow up of four patients and demonstrated that sodium hydrogen carbonate is effective for treatment of chronic metabolic acidosis in GS deficieny.

  8. The evaluation of the efficacy of sodium carbonate as zearalenone destructor in feeding stuffs.

    Science.gov (United States)

    Polak, M; Gajecki, M; Kulik, T; Łuczyński, M K; Obremski, K; Góra, M; Gajecka, M; Jakimiuk, E; Zielonka, Ł

    2009-01-01

    Contamination of feed with zearalenone (ZEA) is still a serious problem in farm animals feeding, especially in gilts, sensitive to this compound. The relative failure of current methods of decontamination and quality control lead us to look for new techniques. The commonly accepted method for breaking down ZEA was performed in controlled temperature and time conditions. Various sodium carbonate doses (0.5 - 4%) were added to feed naturally contaminated with ZEA (ZEA biosynthesis by F. graminearum isolates). These doses were found to be effective in in vitro studies. The addition of 2% sodium carbonate gave the best results in reducing the phytoestrogen in the feed.

  9. Modelling with response surface methodology of the effects of egg yolk, egg white and sodium carbonate on some textural properties of beef patties.

    Science.gov (United States)

    Parlak, Ozgür; Zorba, Omer; Kurt, Sükrü

    2014-04-01

    This study was accomplished to determine the effects of egg yolk, egg white and sodium carbonate on textural properties of beef patties by using Central Composite Design of Response Surface Methodology. Meat patties were prepared using beef, lamb tail fat and spices. Effects of addition of egg yolk powder (0-1%), egg white powder (0-1%) and sodium carbonate (0-1%) on textural properties were studied by using a texture analyzer. The TPA and cutting force tests were measured in the samples. Effects of sodium carbonate were found to be significant (P  0.05). The levels of sodium carbonate up to 0.72% improved the textural properties of beef patties.

  10. Conversion of Carbon Dioxide into Ethanol by Electrochemical Synthesis Method Using Cu-Zn Electrode

    Science.gov (United States)

    Riyanto; Ramadan, S.; Fariduddin, S.; Aminudin, A. R.; Hayatri, A. K.

    2018-01-01

    Research on conversion of carbon dioxide into ethanol has been done. The conversion process is carried out in a sodium bicarbonate electrolyte solution in an electrochemical synthesis reactor. As cathode was used Cu-Zn, while as anode carbon was utilized. Variations of voltage, concentration of sodium bicarbonate electrolyte solution and time of electrolysis were performed to determine the optimum conditions to convert carbon dioxide into ethanol. Sample of the electrochemical synthesis process was analyzed by gas chromatography. From the result, it is found that the optimum conditions of the electrochemical synthesis process of carbon dioxide conversion into ethanol are voltage, concentration of sodium bicarbonate electrolyte solution and time of electrolysis are 3 volts, 0.4 M and 90 minutes with the ethanol concentration of 10.44%.

  11. Contribution to the simultaneous determination of several light elements in alkalin metals by gamma photon and charged particle activation. Application to carbon and nitrogen determination in sodium

    International Nuclear Information System (INIS)

    Bock, Patrice.

    1976-10-01

    A new γ activation method for the simultaneous determination of carbon and nitrogen in sodium is described. It makes use of the nuclear reactions: 12 C(γ,n) 11 C and 14 N(γ,n) 13 N. The process used to separate carbone-11 and nitrogen-13 from sodium with a view to their radio-activity determination is based on vacuum dissolution of the sample in a mixture of oxidizing and acid fused salts. The oxidized carbon is trapped as CO 2 on soda asbestos and the nitrogen as N 2 on molecular sieve at -196 deg C. The efficiency of the technique is estimated by means of tracer tests and by proton activation. The relative influence of competitive nuclear reactions on elements close to the above two impurities, or even on the matrix itself, is examined. The method described has a theoretical detection limit of some 10 -8 g.g -1 for the two elements in question and mean concentrations of 0.3+-0.1x10 -6 g.g -1 carbon and 1.0+-0.5x10 -6 g.g -1 nitrogen have in fact been measured in a batch of 0.5 g sodium samples [fr

  12. Source contributions to atmospheric fine carbon particle concentrations

    Science.gov (United States)

    Andrew Gray, H.; Cass, Glen R.

    A Lagrangian particle-in-cell air quality model has been developed that facilitates the study of source contributions to atmospheric fine elemental carbon and fine primary total carbon particle concentrations. Model performance was tested using spatially and temporally resolved emissions and air quality data gathered for this purpose in the Los Angeles area for the year 1982. It was shown that black elemental carbon (EC) particle concentrations in that city were dominated by emissions from diesel engines including both on-highway and off-highway applications. Fine primary total carbon particle concentrations (TC=EC+organic carbon) resulted from the accumulation of small increments from a great variety of emission source types including both gasoline and diesel powered highway vehicles, stationary source fuel oil and gas combustion, industrial processes, paved road dust, fireplaces, cigarettes and food cooking (e.g. charbroilers). Strategies for black elemental carbon particle concentration control will of necessity need to focus on diesel engines, while controls directed at total carbon particle concentrations will have to be diversified over a great many source types.

  13. [Preoperatively administered flomoxef sodium concentration in aqueous humor].

    Science.gov (United States)

    Miyamoto, Mariko; Watanabe, Yoichiro; Mizuki, Nobuhisa

    2007-04-01

    We intravenously administered flomoxef sodium (FMOX) 0.5-3.5 hours before cataract surgery and measured the concentration of the agent in the aqueous humor to investigate its penetration into the aqueous humor and its efficacy in the prevention of postoperative endophthalmitis. 56 patients who underwent cataract surgery were enrolled in this study. They received 1 g FMOX via a 20-minute intravenous drip beginning 0.5-3.5 hours before the operation. Aqueous humor was aspirated from the anterior chamber and assayed for FMOX concentration using high-performance liquid chromatography. The mean intraoperative FMOX concentrations in the patients' aqueous humor were 0.79 +/- 0.24 microg/ml (administered 3.5 hours before surgery)--1.47 0.79 microg/ml (administered 1.5 hours before surgery). These concentrations administered 0.5-3.0 hours before surgery sufficiently exceeded the minimum inhibitory concentration (MIC) 90 values against Staphylococcus epidermidis, Staphylococcus aureus and Propionibacterium acnes, but did not achieve the MIC90 values against Enterococcus faecalis and Pseudomonas aeruginosa. The FMOX concentrations in the aqueous humor sampling were adequate to kill bacteria in vitro. This drug may be efficacious in the prevention of postoperative endophthalmitis in patients undergoing cataract surgery.

  14. High cyclability of carbon-coated TiO2 nanoparticles as anode for sodium-ion batteries

    International Nuclear Information System (INIS)

    Ge, Yeqian; Jiang, Han; Zhu, Jiadeng; Lu, Yao; Chen, Chen; Hu, Yi; Qiu, Yiping; Zhang, Xiangwu

    2015-01-01

    Highlights: • Titanium oxide nanopaticles were modified by carbon coating from pyrolyzing of PVP. • Carbon coating gave rise to excellent cycling ability of TiO 2 for sodium-ion batteries. • The reversible capacity of carbon-coated TiO 2 reached 242.3 mAh g −1 at 30 mA g −1 . • Good rate performance of carbon-coated TiO 2 was presented up to 800 mA g −1 . - Abstract: Owing to the merits of good chemical stability, elemental abundance and nontoxicity, titanium dioxide (TiO 2 ) has drawn increasing attraction for use as anode material in sodium-ion batteries. Nanostructured TiO 2 was able to achieve high energy density. However, nanosized TiO 2 is typically electrochemical instable, which leads to poor cycling performance. In order to improve the cycling stability, carbon from thermolysis of poly(vinyl pyrrolidone) was coated onto TiO 2 nanoparticles. Electronic conductivity and electrochemical stability were enhanced by coating carbon onto TiO 2 nanoparticles. The resultant carbon-coated TiO 2 nanoparticles exhibited high reversible capacity (242.3 mAh g −1 ), high coulombic efficiency (97.8%), and good capacity retention (87.0%) at 30 mA g −1 over 100 cycles. By comparison, untreated TiO 2 nanoparticles showed comparable reversible capacity (237.3 mAh g −1 ) and coulombic efficiency (96.2%), but poor capacity retention (53.2%) under the same condition. The rate performance of carbon-coated TiO 2 nanoparticles was also displayed as high as 127.6 mAh g −1 at a current density of 800 mA g −1 . The improved cycling performance and rate capability were mostly attributed to protective carbon layer helping stablize solid electrolyte interface formation of TiO 2 nanoparticles and improving the electronic conductivity. Therefore, it is demonstrated that carbon-coated TiO 2 nanoparticles are promising anode candidate for sodium-ion batteries

  15. [The relationship between PMI and concentration of potassium ion and sodium ion in swine aqueous humor after death].

    Science.gov (United States)

    Han, Ju; Yu, Guang-biao; Dong, Ye-qiang; Fang, Chao; Jing, Hua-lan; Luo, Si-min

    2010-04-01

    To explored the relationship between the concentration of potassium ion as well as sodium ion in the aqueous humor and post-mortem interval (PMI). The concentrations of potassium ion and sodium ion in the aqueous humor of swine within 48 h after death at 4 degrees C and 28 degrees C were detected using Z-500 atomic absorption spectrophotometer. The concentrations of potassium ion and sodium ion in aqueous humor of isolated swine eyeballs within 48 h after death when the environmental temperature was 4 degrees C were significantly related to PMI. The relationship between PMI and the concentration of potassium ion was PMI = -0.178[K+]2 + 49.978 (R2 = 0.995). The relationship between PMI and the rate of sodium ion and potassium ion was PMI = 120.987/[Na+/K+]-28.834 (R2 = 0.905). The concentration of potassium in aqueous humor of isolated swine eyeballs may be one of the reference indicators to estimate PMI of the corpses at lower temperatures.

  16. 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)

  17. Renal blood flow, early distal sodium, and plasma renin concentrations during osmotic diuresis

    DEFF Research Database (Denmark)

    Leyssac, P P; Holstein-Rathlou, N H; Skøtt, O

    2000-01-01

    .6 mmHg. Urine flow increased 10-fold, and sodium excretion increased by 177%. Plasma renin concentration (PRC) increased by 58%. Renal blood flow and glomerular filtration rate decreased, however end-proximal flow remained unchanged. After a similar volume of hypotonic glucose (152 mM), ED......(NaCl) increased by 3.6 mM, (P renal hemodynamics, urine flow, sodium excretion rate, or PRC. Infusion of 300 micromol NaCl in a smaller volume caused ED(NaCl) to increase by 6.4 mM without significant changes in PRC. Urine flow and sodium excretion increased significantly...

  18. Use of sodium carbonate as a binder in ceramic tile compositions; Uso del carbonato sodico como ligante en composiciones de baldosas ceramicas

    Energy Technology Data Exchange (ETDEWEB)

    Quereda, F.; Sanchez, E.; Garcia-Ten, J.; Gozalbo, A.; Beltran, V.; Sanchez, J.; Sales, J.

    2010-07-01

    This study analyses, first, the influence of sodium carbonate content on the behaviour of the ceramic tile body composition during the different manufacturing process stages (preparation of the suspension, pressing, and firing), as well as on unfired tile mechanical strength. It has been verified that sodium carbonate can be used as a binder in ceramic tile compositions, since small percentages considerably enhance dry tile mechanical strength. It has furthermore been determined that for each composition there is an optimum addition content, with high increased mechanical strength (up to 70%), without this noticeably affecting the rheological behaviour of the suspension to be spray dried. These results are currently being patented (patent application P200930148). Once the binding effect of sodium carbonate had been verified, it was sought to establish its action mechanism. For this purpose, drops of mixtures of a standard ceramic composition and increasing quantities of sodium carbonate were prepared. The drops were rapidly dried and the granules were characterised by scanning electron microscopy. It was thus verified that the most likely sodium carbonate action mechanism was formation of solid bridges by crystallisation. (Author)

  19. Assessing the chemical involvement of limestone powder in sodium carbonate activated slag

    NARCIS (Netherlands)

    Yuan, B.; Yu, Q.; Brouwers, H.J.H.

    2017-01-01

    This study aims to investigate the effect of limestone powder (LP) on the reaction of sodium carbonate activated slag. The results show that the incorporated LP up to 30% improves the strength development, especially at advanced curing ages. A slightly accelerated reaction is observed for samples

  20. Improving the desulfurization performance of CaCO3 with sodium humate

    Science.gov (United States)

    Feng, Run; Sun, Zhiguo; Zhang, Wenqing; Huang, Hao; Hu, Haihang; Zhang, Li; Xie, Hongyong

    2018-02-01

    The influence of these factors on desulphurization efficiency was studied by changing the amount of calcium carbonate, the concentration of sulfur dioxide, the liquid flow rate of absorbent and the air flow rate, the optimum working condition was determined by the research of limestone-gypsum desulphurization process commonly used in industry. By changing the amount of calcium carbonate, we conclude that the volume of water in the desulfurization efficiency does not increase with the adding amount of calcium carbonate. The optimum conditions were determined : at the condicion of the concentration of 500ppm of sulfur dioxide, 10g calcium carbonate, 150L/h liquid flow and the minimum air flow rate of 6.75m3/h, the highest desulfurization efficiency was close to 100% when sodium humate was not added, but the holding time was only about 5 minutes. After adding 3g of humic acid, the desulfurization efficiency was improved obviously, and the instantaneous efficiency of 100% lasting for about 40 minutes. It can be seen that, calcium carbonate in the addition of humic acid sodium can significantly improve the absorption of calcium carbonate performance of SO2.

  1. Inactivation of Foot-and-Mouth Disease Virus by Citric Acid and Sodium Carbonate with Deicers

    Science.gov (United States)

    Hong, Jang-Kwan; You, Su-Hwa; Kim, Su-Mi; Tark, Dongseob; Lee, Hyang-Sim; Ko, Young-Joon; Seo, Min-Goo; Park, Jong-Hyeon; Kim, Byounghan

    2015-01-01

    Three out of five outbreaks of foot-and-mouth disease (FMD) since 2010 in the Republic of Korea have occurred in the winter. At the freezing temperatures, it was impossible to spray disinfectant on the surfaces of vehicles, roads, and farm premises because the disinfectant would be frozen shortly after discharge and the surfaces of the roads or machines would become slippery in cold weather. In this study, we added chemical deicers (ethylene glycol, propylene glycol, sodium chloride, calcium chloride, ethyl alcohol, and commercial windshield washer fluid) to keep disinfectants (0.2% citric acid and 4% sodium carbonate) from freezing, and we tested their virucidal efficacies under simulated cold temperatures in a tube. The 0.2% citric acid could reduce the virus titer 4 logs at −20°C with all the deicers. On the other hand, 4% sodium carbonate showed little virucidal activity at −20°C within 30 min, although it resisted being frozen with the function of the deicers. In conclusion, for the winter season, we may recommend the use of citric acid (>0.2%) diluted in 30% ethyl alcohol or 25% sodium chloride solvent, depending on its purpose. PMID:26319879

  2. Effect of different concentrations of sodium hyaluronate on the ocular surface change of dry eye in New Zealand rabbits

    Directory of Open Access Journals (Sweden)

    Shuang-Yong Wang

    2015-10-01

    Full Text Available AIM:To observe the effect of different concentrations of sodium hyaluronate on ocular surface change of dry eye. METHODS: New Zealand rabbits with dry eye was prepared and treated with 0.1% and 0.3% sodium hyaluronate drops fluid respectively, which were regarded as low concentration treatment group(group Band high concentration treatment group(group Crespectively. However, the rabbits treated with saline were regarded as control group(group A. And then, corneal fluorescein staining, Schirmer test, conjunctival goblet cells, mucin expression and histological changes were observed.RESULTS: On D7 and D14 after treatment, corneal fluorescein staining scores were lower in group B and group C than that in group A(PP PCONCLUSION: The sodium hyaluronate can improve ocular surface damage of dry eye in New Zealand rabbits. The high concentration of sodium hyaluronate has better effect than low concentration.

  3. Reactive extraction of carboxylic acids from apolar hydrocarbons using aqueous solutions of sodium hydrogen carbonate with back-recovery using carbon dioxide under pressure

    NARCIS (Netherlands)

    Kuzmanovic, B.; Kuipers, N.J.M.; de Haan, A.B.; Kwant, Gerard

    2005-01-01

    A combination of using an aqueous solution of sodium hydrogen carbonate for forward-extraction of carboxylic acids from a dilute apolar organic solvent, and carbon dioxide under pressure for its back-recovery, is studied. Used in combination, these two steps might provide a technique for the

  4. Room temperature synthesis of glycerol carbonate catalyzed by spray dried sodium aluminate microspheres

    OpenAIRE

    Sreerangappa, Ramesh; Debecker, Damien P.; 13th European Congress on Catalysis – EuropaCat 2017

    2017-01-01

    Nanostructured NaAlO2 microspheres are produced by one-pot spray dried route, and are characterized by various physico-chemical methods. The obtained solids are composed of spherical aggregates of sodium aluminate with small crystallite size and strong surface basicity. This makes them highly active catalysts in the base-catalyzed synthesis of glycerol carbonate from glycerol and dimethyl carbonate. The catalyst does not leach and showed good reusability up to three cycles.

  5. Fission product concentration evolution in sodium pool following a fuel subassembly failure in an LMFBR

    International Nuclear Information System (INIS)

    Natesan, K.; Velusamy, K.; Selvaraj, P.; Kasinathan, N.; Chellapandi, P.; Chetal, S.; Bhoje, S.

    2003-01-01

    During a fuel element failure in a liquid metal cooled fast breeder reactor, the fission products originating from the failed pins mix into the sodium pool. Delayed Neutron Detectors (DND) are provided in the sodium pool to detect such failures by way of detection of delayed neutrons emitted by the fission products. The transient evolution of fission product concentration is governed by the sodium flow distribution in the pool. Transient hydraulic analysis has been carried out using the CFD code PHOENICS to estimate fission product concentration evolution in hot pool. k- ε turbulence model and zero laminar diffusivity for the fission product concentration have been considered in the analysis. Times at which the failures of various fuel subassemblies (SA) are detected by the DND are obtained. It has been found that in order to effectively detect the failure of every fuel SA, a minimum of 8 DND in hot pool are essential

  6. Technical Information on the Carbonation of the EBR-II Reactor, Summary Report Part 1: Laboratory Experiments and Application to EBR-II Secondary Sodium System

    Energy Technology Data Exchange (ETDEWEB)

    Steven R. Sherman

    2005-04-01

    Residual sodium is defined as sodium metal that remains behind in pipes, vessels, and tanks after the bulk sodium metal has been melted and drained from such components. The residual sodium has the same chemical properties as bulk sodium, and differs from bulk sodium only in the thickness of the sodium deposit. Typically, sodium is considered residual when the thickness of the deposit is less than 5-6 cm. This residual sodium must be removed or deactivated when a pipe, vessel, system, or entire reactor is permanently taken out of service, in order to make the component or system safer and/or to comply with decommissioning regulations. As an alternative to the established residual sodium deactivation techniques (steam-and-nitrogen, wet vapor nitrogen, etc.), a technique involving the use of moisture and carbon dioxide has been developed. With this technique, sodium metal is converted into sodium bicarbonate by reacting it with humid carbon dioxide. Hydrogen is emitted as a by-product. This technique was first developed in the laboratory by exposing sodium samples to humidified carbon dioxide under controlled conditions, and then demonstrated on a larger scale by treating residual sodium within the Experimental Breeder Reactor II (EBR-II) secondary cooling system, followed by the primary cooling system, respectively. The EBR-II facility is located at the Idaho National Laboratory (INL) in southeastern Idaho, U.S.A. This report is Part 1 of a two-part report. It is divided into three sections. The first section describes the chemistry of carbon dioxide-water-sodium reactions. The second section covers the laboratory experiments that were conducted in order to develop the residual sodium deactivation process. The third section discusses the application of the deactivation process to the treatment of residual sodium within the EBR-II secondary sodium cooling system. Part 2 of the report, under separate cover, describes the application of the technique to residual sodium

  7. Carbonic acid ionization and the stability of sodium bicarbonate and carbonate ion pairs to 200 °C - A potentiometric and spectrophotometric study

    Science.gov (United States)

    Stefánsson, Andri; Bénézeth, Pascale; Schott, Jacques

    2013-11-01

    Carbonic acid ionization and sodium bicarbonate and carbonate ion pair formation constants have been experimentally determined in dilute hydrothermal solutions to 200 °C. Two experimental approaches were applied, potentiometric acid-base titrations at 10-60 °C and spectrophotometric pH measurements using the pH indicators, 2-napthol and 4-nitrophenol, at 25-200 °C. At a given temperature, the first and second ionization constants of carbonic acid (K1, K2) and the ion pair formation constants for NaHCO(aq)(K) and NaCO3-(aq)(K) were simultaneously fitted to the data. Results of this study compare well with previously determined values of K1 and K2. The NaHCO(aq) and NaCO3-(aq) ion pair formation constants vary between 25 and 200 °C having values of logK=-0.18 to 0.58 and logK=1.01 to 2.21, respectively. These ion pairs are weak at low-temperatures but become increasingly important with increasing temperature under neutral to alkaline conditions in moderately dilute to concentrated NaCl solutions, with NaCO3-(aq) predominating over CO32-(aq) in ⩾0.1 M NaCl solution at temperatures above 100 °C. The results demonstrate that NaCl cannot be considered as an inert (non-complexing) electrolyte in aqueous carbon dioxide containing solutions at elevated temperatures.

  8. In situ Microscopic Observation of Sodium Deposition/Dissolution on Sodium Electrode

    OpenAIRE

    Yuhki Yui; Masahiko Hayashi; Jiro Nakamura

    2016-01-01

    Electrochemical sodium deposition/dissolution behaviors in propylene carbonate-based electrolyte solution were observed by means of in situ light microscopy. First, granular sodium was deposited at pits in a sodium electrode in the cathodic process. Then, the sodium particles grew linearly from the electrode surface, becoming needle-like in shape. In the subsequent anodic process, the sodium dissolved near the base of the needles on the sodium electrode and the so-called ?dead sodium? broke a...

  9. Flomoxef sodium and levofloxacin concentrations in aqueous humor.

    Science.gov (United States)

    Mizuki, Nobuhisa; Watanabe, Yoichiro; Miyamoto, Mariko; Iijima, Yasuhito; Takiyama, Naoaki; Ito, Yoshiki; Ito, Norihiko; Nishida, Tomomi; Iwata, Shinko; Endo, Yoko; Ito, Daizo

    2005-01-01

    We intravenously administered flomoxef sodium (FMOX) 120 minutes before cataract surgery, topically administered levofloxacin (LVFX) into the eyes four times at 30-minute intervals before surgery, and measured the aqueous humor concentrations of these agents to investigate their penetration into the aqueous humor and their efficacy in the prevention of postoperative endophthalmitis. Sixty-eight patients who underwent cataract surgery at the Department of Ophthalmology, Yokohama City University School of Medicine, or its affiliate, Kanazawa Hospital, Yokohama, were enrolled in this study. They received one or both of the following: 1.0 g FMOX via a 20-minute intravenous drip and LVFX ophthalmic solution applied four times at 30-minute intervals, both beginning two hours before the operation. Aqueous humor was aspirated from the anterior chamber and assayed for FMOX and LVFX concentrations using high-performance liquid chromatography (HPLC). The mean intraoperative FMOX and LVFX concentrations in the patients' aqueous humor were 1.21 +/- 0.63 microg/ml and 0.69 +/- 0.47 microg/ml, respectively. These concentrations sufficiently exceeded the MIC90 values against Staphylococcus epidermidis, S. aureus, and Propionibacterium acnes. The FMOX and LVFX concentrations in the aqueous humor sampling were adequate to kill bacteria in vitro. These drugs may have efficacy in the prevention of postoperative endophthalmitis in patients undergoing cataract surgery.

  10. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    International Nuclear Information System (INIS)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Douglas P. Harrison; Ya Liang

    2001-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO(sub 2) as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO(sub 2) stream after condensation of water vapor. Testing conducted previously confirmed that the reaction rate and achievable CO(sub 2) capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO(sub 2) and H(sub 2)O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbon dioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed-bed, fluidized-bed, and transport

  11. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Douglas P. Harrison; Ya Liang

    2001-10-01

    The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. Testing conducted previously confirmed that the reaction rate and achievable CO{sub 2} capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO{sub 2} and H{sub 2}O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbon dioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed

  12. Sodium fire protection

    International Nuclear Information System (INIS)

    Raju, C.; Kale, R.D.

    1979-01-01

    Results of experiments carried out with sodium fires to develop extinguishment techniques are presented. Characteristics, ignition temperature, heat evolution and other aspects of sodium fires are described. Out of the powders tested for extinguishment of 10 Kg sodium fires, sodium bi-carbonate based dry chemical powder has been found to be the best extinguisher followed by large sized vermiculite and then calcium carbonate powders distributed by spray nozzles. Powders, however, do not extinguish large fires effectively due to sodium-concrete reaction. To control large scale fires in a LMFBR, collection trays with protective cover have been found to cause oxygen starvation better than flooding with inert gas. This system has an added advantage in that there is no damage to the sodium facilities as has been in the case of powders which often contain chlorine compounds and cause stress corrosion cracking. (M.G.B.)

  13. 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)

  14. Quantification of Kinetic Rate Law Parameters of Uranium Release from Sodium Autunite as a Function of Aqueous Bicarbonate Concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Gudavalli, Ravi; Katsenovich, Yelena; Wellman, Dawn M.; Lagos, Leonel; Tansel, Berrin

    2013-09-05

    ABSTRACT: Hydrogen carbonate is one of the most significant components within the uranium geochemical cycle. In aqueous solutions, hydrogen carbonate forms strong complexes with uranium. As such, aqueous bicarbonate may significantly increase the rate of uranium release from uranium minerals. Quantifying the relationship of aqueous hydrogen carbonate solutions to the rate of uranium release during dissolution is critical to understanding the long-term fate of uranium within the environment. Single-pass flow-through (SPTF) experiments were conducted to estimate the rate of uranium release from Na meta-autunite as a function of bicarbonate solutions (0.0005-0.003 M) under the pH range of 6-11 and temperatures of 5-60oC. Consistent with the results of previous investigation, the rate of uranium release from sodium autunite exhibited minimal dependency on temperature; but were strongly dependent on pH and increasing concentrations of bicarbonate solutions. Most notably at pH 7, the rate of uranium release exhibited 370 fold increases relative to the rate of uranium release in the absence of bicarbonate. However, the effect of increasing concentrations of bicarbonate solutions on the release of uranium was significantly less under higher pH conditions. It is postulated that at high pH values, surface sites are saturated with carbonate, thus the addition of more bicarbonate would have less effect on uranium release. Results indicate the activation energies were unaffected by temperature and bicarbonate concentration variations, but were strongly dependent on pH conditions. As pH increased from 6 to 11, activation energy values were observed to decrease from 29.94 kJ mol-1 to 13.07 kJ mol-1. The calculated activation energies suggest a surface controlled dissolution mechanism.

  15. Inactivation of foot-and-mouth disease virus by citric acid and sodium carbonate with deicers.

    Science.gov (United States)

    Hong, Jang-Kwan; Lee, Kwang-Nyeong; You, Su-Hwa; Kim, Su-Mi; Tark, Dongseob; Lee, Hyang-Sim; Ko, Young-Joon; Seo, Min-Goo; Park, Jong-Hyeon; Kim, Byounghan

    2015-11-01

    Three out of five outbreaks of foot-and-mouth disease (FMD) since 2010 in the Republic of Korea have occurred in the winter. At the freezing temperatures, it was impossible to spray disinfectant on the surfaces of vehicles, roads, and farm premises because the disinfectant would be frozen shortly after discharge and the surfaces of the roads or machines would become slippery in cold weather. In this study, we added chemical deicers (ethylene glycol, propylene glycol, sodium chloride, calcium chloride, ethyl alcohol, and commercial windshield washer fluid) to keep disinfectants (0.2% citric acid and 4% sodium carbonate) from freezing, and we tested their virucidal efficacies under simulated cold temperatures in a tube. The 0.2% citric acid could reduce the virus titer 4 logs at -20°C with all the deicers. On the other hand, 4% sodium carbonate showed little virucidal activity at -20°C within 30 min, although it resisted being frozen with the function of the deicers. In conclusion, for the winter season, we may recommend the use of citric acid (>0.2%) diluted in 30% ethyl alcohol or 25% sodium chloride solvent, depending on its purpose. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  16. 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 ...

  17. 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

  18. Room temperature synthesis of glycerol carbonate catalyzed by spray dried sodium aluminate microspheres

    OpenAIRE

    Sreerangappa, Ramesh; Debecker, Damien P.

    2017-01-01

    Nanostructured NaAlO2 microspheres are produced from an aqueous solution, by a one-pot spray drying route. The obtained solids are composed of spherical aggregates of sodium aluminate with small crystallite size and strong surface basicity. This makes them highly active catalysts in the base-catalyzed synthesis of glycerol carbonate from glycerol and dimethyl carbonate. The new catalyst does not leach and is recyclable. NaAlO2 microspheres outcompete commercially available NaAlO2 as well as o...

  19. Cadmium, zinc, copper, sodium and potassium concentrations in rooster and turkey semen and their correlation.

    Science.gov (United States)

    Massanyi, Peter; Weis, Jan; Lukac, Norbert; Trandzik, Jozef; Bystricka, Judita

    2008-04-01

    The purpose of this study was to assess concentration of selected elements (cadmium, zinc, copper, sodium and potassium) in rooster and turkey semen and to find possible correlations between these elements. Samples were analyzed on the atomic absorption spectrophotometer. The analysis of cadmium showed that the concentration in rooster is 9.06 +/- 7.70 and in turkey 4.10 +/- 3.59 microg/mL. In zinc 5.25 +/- 1.96 microg/mL in rooster and 3.70 +/- 1.26 microg/mL in turkey were detected. Higher concentration of copper was found in rooster semen (6.79 +/- 6.42 microg/mL) in comparison with turkey semen (4.29 +/- 5.43 microg/mL). The level of sodium (3.96 +/- 1.02 microg/mL; 3.14 +/- 0.85 microg/mL) and potassium (2.88 +/- 0.65 microg/mL; 3.42 +/- 1.41 microg/mL) was very similar in both species. Correlation analysis detected high positive correlation between cadmium and zinc (r = 0.701) in rooster and between sodium and potassium (r = 0.899) in turkey semen.

  20. Long-term progress prediction for the carbon steel corrosion in diluted artificial seawater with and without zinc / sodium carbonate mixed phosphate

    International Nuclear Information System (INIS)

    Fujii, Kazumi; Ishioka, Shinichi; Iwanami, Masaru; Kaneko, Tetsuji; Tanaka, Norihiko; Kawaharada, Yoshiyuki; Yokoyama, Yutaka; Umehara, Ryuji; Kato, Chiaki; Ueno, Fumiyoshi; Fukaya, Yuichi; Kumaga, Katsuhiko

    2017-01-01

    The Fukushima Daiichi Nuclear Power Plants (1F) were damaged by an unprecedented severe accident in the great east Japan earthquake on 11th, March, 2011, and seawater and fresh water were injected as an emergency countermeasure for the core cooling. The primary containment vessels (PCVs), made of carbon steel, were exposed to seawater and fresh water, and have had the possibility of corrosion. The PCVs of 1F are the most important equipment for the core cooling and removal of the fuel debris, the structural integrity of the PCV must be maintained until decommissioning. Therefore, evaluation of PCV carbon steel corrosion behavior is important, as well as evaluation of corrosion inhibitors as one of the corrosion protection methods. In this study, long-term immersion corrosion tests for up to 10000 hours were performed in diluted artificial seawater simulating 1F with and without zinc / sodium carbonate mixed phosphate. Based on the long-term immersion corrosion test results, diagnosis method of the reduction in plate thickness of the nuclear vessel was examined. The validity of the existing corrosion progress models following parabolic rate law was confirmed. The corrosion progress models were also applicable to the corrosion inhibited condition adding zinc / sodium carbonate mixed phosphate. It was found that the corrosion rate of carbon steel drastically fell down by adding this corrosion inhibitor. (author)

  1. On the Sodium Concentration Diffusion with Three-Dimensional Extracellular Stimulation

    Directory of Open Access Journals (Sweden)

    Luisa Consiglieri

    2011-01-01

    Full Text Available We deal with the transmembrane sodium diffusion in a nerve. We study a mathematical model of a nerve fibre in response to an imposed extracellular stimulus. The presented model is constituted by a diffusion-drift vectorial equation in a bidomain, that is, two parabolic equations defined in each of the intra- and extra-regions. This system of partial differential equations can be understood as a reduced three-dimensional Poisson-Nernst-Planck model of the sodium concentration. The representation of the membrane includes a jump boundary condition describing the mechanisms involved in the excitation-contraction couple. Our first novelty comes from this general dynamical boundary condition. The second one is the three-dimensional behaviour of the extracellular stimulus. An analytical solution to the mathematical model is proposed depending on the morphology of the excitation.

  2. Turning into carbonate the residual sodium left in BN-350 circuits may alleviate concerns over their long term safe confinement

    International Nuclear Information System (INIS)

    Rahmani, L

    2000-01-01

    After the coolant is drained from the reactor vessel and from the primary and secondary circuits of the BN-350 nuclear power plant, what sodium is left in ponds and films may amount to hundreds of kilograms. For the long term safe storage period which is to follow, preliminary safety analyses (e.g. derived from those made for French sodium cooled reactors) might show that the risks incurred through loss of leaktightness are significant. The ingress of moisture into the circuits would generate, by reaction with the sodium, two undesirable products : sodium hydroxide and hydrogene. Even when considering that water would enter the circuits progressively, so that the heat of the reaction does not give rise to over-pressure, some main risk factors remain. The most promising solution to this challenge appears to be the carbonation of the sodium residues, by progressive diffusion of an appropriate association of carbon dioxyde and water vapour through the inert gaseous medium which fills the circuits. The desired product is porous sodium hydrogenocarbonate

  3. A Novel Method for Analysis of Dissolved Inorganic Carbon Concentration and δ13C by Cavity Ring-Down Spectroscopy

    Science.gov (United States)

    Smith, E.; Gonneea, M. E.; Boze, L. G.; Casso, M.; Pohlman, J.

    2017-12-01

    Dissolved inorganic carbon (DIC) is the largest pool of carbon in the oceans and is where about half of anthropogenic carbon dioxide (CO2) emissions are being sequestered. Determining the concentration and stable carbon isotopic content (δ13C) of DIC allows us to delineate carbon sources that contribute to marine DIC. A simple and reliable method for measuring DIC concentration and δ13C can be used to apportion contributions from external sources and identify effects from biogeochemical reactions that contribute or remove DIC. The U.S. Geological Survey has developed a discrete sample analysis module (DSAM) that interfaces to a Picarro G-2201i cavity ring-down spectrometer (CRDS, Picarro Inc.) to analyze CO2 and methane concentrations and δ13C from discrete gas samples. In this study, we adapted the USGS DSAM-CRDS analysis system to include an AutoMate prep device (Automate FX, Inc.) for analysis of DIC concentration and δ13C from aqueous samples. The Automate prep device was modified to deliver CO2 extracted from DIC to the DSAM, which conditions and transfers the gas to the CRDS. LabVIEW software (National Instruments) triggers the Automate Prep device, controls the DSAM and collects data from the CRDS. CO2 mass concentration data are obtained by numerical integration of the CO2 volumetric concentrations output by the CRDS and subsequent comparison to standard materials. CO2 carbon isotope values from the CRDS (iCO2) are converted to δ13C values using a slope and offset correction calibration procedure. The system design and operation was optimized using sodium bicarbonate (NaHCO3) standards and a certified reference material. Surface water and pore water samples collected from Sage Lot Pond, a salt marsh in Cape Cod MA, have been analyzed for concentration by coulometry and δ13C by isotope ratio mass spectrometry and will be used to validate the DIC-DSAM-CRDS method for field applications.

  4. The monitoring of oxygen, hydrogen and carbon in the sodium circuits of the PFR

    International Nuclear Information System (INIS)

    Mason, L.; Morrison, N.S.; Robertson, C.M.; Trevillion, E.A.

    1984-01-01

    The paper reviews the instrumentation available for monitoring oxygen, hydrogen, tritium and carbon impurity levels on the primary and secondary circuits of PFR. Circuit oxygen levels measured using electrochemical oxygen meters are compared to estimates from circuit plugging meters. The data are interpreted in the light of information from cold trap temperatures. Measurements of secondary circuit hydrogen levels using both the sodium and gas phase hydrogen detection equipment are compared to estimates of circuit hydrogen levels from plugging meters and variations in sodium phase hydrogen levels during power operation are discussed. (author)

  5. The use of sodium carbonate to improve curing treatments against green and blue moulds on citrus fruits.

    Science.gov (United States)

    Plaza, Pilar; Usall, Josep; Torres, Rosario; Abadias, Maribel; Smilanick, Joseph L; Viñas, Immaculada

    2004-08-01

    The effectiveness of curing oranges and lemons at 33 degrees C for 65h followed by storage under ambient and cold-storage conditions was investigated. This treatment effectively reduced the incidence of Penicillium digitatum (Pers) Sacc and P italicum Wehmer decay on inoculated and naturally infected oranges and lemons stored at 20 degrees C for 7 days. However, it failed to control green and blue mould infections on fruits placed in long-term cold storage, except green mould on oranges, which was effectively controlled. Dipping fruits in a sodium carbonate solution (20 g litre(-1)) for 2.5 min following a curing treatment at 33 degrees C for 65 h satisfactorily reduced green and blue mould incidence during subsequent long-term storage at 4 degrees C on oranges and at 10 degrees C on lemons. The efficacy was greater on injured fruits inoculated after the combination of treatments was applied, achieving a 60-80% reduction in decay in comparison with the curing treatment alone in all cases. A significant reduction of blue mould was also observed on fruits inoculated both before the treatments and on those re-inoculated after the treatments, demonstrating both protectant and eradicant activity. Thus, combining curing at 33 degrees C for 65 h with sodium carbonate treatment effectively controlled these post-harvest diseases on artificially inoculated citrus fruits and protected against re-infection. With naturally inoculated lemons, curing followed by sodium carbonate significantly reduced both green and blue mould incidence, but was not superior to curing alone. With naturally infected oranges, curing significantly reduced blue mould, but decay was not reduced further when followed by sodium carbonate treatment.

  6. In vitro study of the effect of a dentifrice containing 8% arginine, calcium carbonate, and sodium monofluorophosphate on acid-softened enamel.

    Science.gov (United States)

    Rege, Aarti; Heu, Rod; Stranick, Michael; Sullivan, Richard J

    2014-01-01

    To investigate the possible mode of action of a dentifrice containing 8% arginine and calcium carbonate (Pro-Argin Technology), and sodium monofluorophosphate in delivering the benefits of preventing acid erosion and rehardening acid-softened enamel. The surfaces of acid-softened bovine enamel specimens were evaluated after application of a dentifrice containing 8% arginine, calcium carbonate, and sodium monofluorophosphate in vitro. Scanning Electron Microscopy (SEM), Electronic Spectrometry for Chemical Analysis (ESCA), and Secondary Ion Mass Spectrometry (SIMS) were used to characterize the enamel surfaces. Exposure of pristine enamel surfaces to citric acid resulted in clear roughening of the surface. Multiple applications of a dentifrice containing 8% arginine, calcium carbonate, and sodium monofluorophosphate to the surface of the enamel resulted in the disappearance of the microscopic voids observed by SEM as a function of treatment applications. The ESCA analysis demonstrated that both the nitrogen and carbonate levels increased as the number of treatments increased, which provides evidence that arginine and calcium carbonate were bound to the surface. Observance of arginine's signature mass fragmentation pattern by SIMS analysis confirmed the identity of arginine on the enamel surface. A series of in vitro experiments has demonstrated a possible mode of action by which a dentifrice containing 8% arginine, calcium carbonate, and sodium monofluorophosphate delivers the benefits of preventing acid erosion and rehardening acid-softened enamel. The combination of arginine and calcium carbonate adheres to the enamel surface and helps to fill the microscopic gaps created by acid, which in turn helps repair the enamel and provides a protective coating against future acid attacks.

  7. Autogenous and drying shrinkage of sodium carbonate activated slag altered by limestone powder incorporation

    NARCIS (Netherlands)

    Yuan, B.; Yu, Q.L.; Dainese, E.; Brouwers, H.J.H.

    2017-01-01

    This paper aims to study the shrinkage mechanism of sodium carbonate activated slag containing limestone powder (LP). The workability, pore structure, reaction kinetics and strength development were characterized. The results show that the autogenous shrinkage increases when the dosage of LP is low

  8. Ionophore-based optical nanosensors incorporating hydrophobic carbon dots and a pH-sensitive quencher dye for sodium detection.

    Science.gov (United States)

    Galyean, A A; Behr, M R; Cash, K J

    2018-01-21

    Nanosensors present a biological monitoring method that is biocompatible, reversible, and nano-scale, and they offer many advantages over traditional organic indicators. Typical ionophore-based nanosensors incorporate nile-blue derivative pH indicators but suffer from photobleaching while quantum dot alternatives pose a potential toxicity risk. In order to address this challenge, sodium selective nanosensors containing carbon dots and a pH-sensitive quencher molecule were developed based on an ion-exchange theory and a decoupled recognition element from the pH indicator. Carbon dots were synthesized and integrated into nanosensors containing a pH-indicator, an analyte-binding ligand (ionophore), and a charge-balancing additive. These nanosensors are ion-selective against potassium (selectivity coefficient of 0.4) and lithium (selectivity coefficient of 0.9). Reversible nanosensor response to sodium is also demonstrated. The carbon dot nanosensors are resistant to changes in optical properties for at least 12 h and display stable selectivity to physiologically-relevant sodium (alpha = 0.5 of 200 mM NaCl) for a minimum of 6 days.

  9. Effect of sodium on the creep-rupture behavior of type 304 stainless steel

    International Nuclear Information System (INIS)

    Natesan, K.; Chopra, O.K.; Kassner, T.F.

    1976-01-01

    Uniaxial creep-rupture data have been obtained for Type 304 stainless steel in the solution-annealed condition and after exposure to a flowing sodium environment at temperatures of 700, 650, and 600 0 C.The specimens were exposed to sodium for time periods between 120 and 5012 h to produce carbon penetration depths of approximately 0.010, 0.020, and 0.038 cm in the steel. Results showed that, as the depth of carbon penetration and the average carbon concentration in the steel increase, the rupture life increases and the minimum creep rate decreases. Creep correlations that relate rupture life, minimum creep rate, and time-to-tertiary creep were developed for the steel in both the solution-annealed and sodium-exposed conditions. Isochronous stress-creep strain curves and results on the calculations of the stress levels for 1 percent creep strain and long-term rupture life are also presented. 11 fig

  10. Carbon and nitrogen transport in sodium systems

    International Nuclear Information System (INIS)

    Schrock, S.L.; Shiels, S.A.; Bagnall, C.

    1976-01-01

    Materials for the liquid metal cooled fast breeder reactor will be exposed to high temperature sodium for time periods up to 30 years. One consequence of this exposure will be changes in the interstitial element concentrations of the alloys and concomitant alterations in their mechanical behavior characteristics. Several ongoing technology programs have as their objective a quantitative definition of the rate and extent of this interstitial movement. The paper summarizes the status of these programs and reports in detail on the results of a recently completed, USERDA funded program at the Advanced Reactors Division of Westinghouse. These results, while substantiating earlier reported trends on interstitial movement, indicate the problem is not as severe as initially estimated. Moreover, the present wastage allowance for most reactor components contains sufficient conservatism to compensate for changes in mechanical strength resulting from this change in interstitial concentration

  11. Biomass carbon micro/nano-structures derived from ramie fibers and corncobs as anode materials for lithium-ion and sodium-ion batteries

    International Nuclear Information System (INIS)

    Jiang, Qiang; Zhang, Zhenghao; Yin, Shengyu; Guo, Zaiping; Wang, Shiquan; Feng, Chuanqi

    2016-01-01

    Highlights: • Ramie fibers and corncobs are used as precursors to prepare the biomass carbons. • The ramie fiber carbon (RFC) took on morphology of 3D micro-rods. • The corncob carbon (CC) possessed a 2D nanosheets structure. • Both RFC and CC exhibited outstanding electrochemical performances in LIBs and SIBs systems. - Abstract: Three-dimensional (3D) rod-like carbon micro-structures derived from natural ramie fibers and two-dimensional (2D) carbon nanosheets derived from corncobs have been fabricated by heat treatment at 700 °C under argon atomsphere. The structure and morphology of the as-obtained ramie fiber carbon (RFC) and corncob carbon (CC) were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) technique. The electrochemical performances of the biomass carbon-based anode in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) were investigated. When tested as anode material for lithium ion batteries, both the RFC microrods and CC nanosheets exhibited high capacity, excellent rate capability, and stable cyclability. The specific capacity were still as high as 489 and 606 mAhg −1 after 180 cycles when cycled at room temperature in a 3.0–0.01 V potential (vs. Li/Li + ) window at current density of 100 mAg −1 , respectively, which are much higher than that of graphite (375 mAhg −1 ) under the same current density. Although the anodes in sodium ion batteries showed poorer specific capability than that in lithium-ion batteries, they still achieve a reversible sodium intercalation capacity of 122 and 139 mAhg −1 with similar cycling stability. The feature of stable cycling performance makes the biomass carbon derived from natural ramie fibers and corncobs to be promising candidates as electrodes in rechargeable sodium-ion batteries and lithium-ion batteries.

  12. Biomass carbon micro/nano-structures derived from ramie fibers and corncobs as anode materials for lithium-ion and sodium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Qiang; Zhang, Zhenghao [Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for Synthesis and Applications of Organic Functional Molecules, Hubei University, Wuhan 430062 (China); Yin, Shengyu [College of Environmental and Biological Engineering, Wuhan Technology and Business University, Wuhan 430065 (China); Guo, Zaiping [Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for Synthesis and Applications of Organic Functional Molecules, Hubei University, Wuhan 430062 (China); Institute for Superconducting & Electronic Materials, University of Wollongong, NSW 2522 (Australia); Wang, Shiquan [Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for Synthesis and Applications of Organic Functional Molecules, Hubei University, Wuhan 430062 (China); Feng, Chuanqi, E-mail: cfeng@hubu.edu.cn [Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for Synthesis and Applications of Organic Functional Molecules, Hubei University, Wuhan 430062 (China)

    2016-08-30

    Highlights: • Ramie fibers and corncobs are used as precursors to prepare the biomass carbons. • The ramie fiber carbon (RFC) took on morphology of 3D micro-rods. • The corncob carbon (CC) possessed a 2D nanosheets structure. • Both RFC and CC exhibited outstanding electrochemical performances in LIBs and SIBs systems. - Abstract: Three-dimensional (3D) rod-like carbon micro-structures derived from natural ramie fibers and two-dimensional (2D) carbon nanosheets derived from corncobs have been fabricated by heat treatment at 700 °C under argon atomsphere. The structure and morphology of the as-obtained ramie fiber carbon (RFC) and corncob carbon (CC) were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) technique. The electrochemical performances of the biomass carbon-based anode in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) were investigated. When tested as anode material for lithium ion batteries, both the RFC microrods and CC nanosheets exhibited high capacity, excellent rate capability, and stable cyclability. The specific capacity were still as high as 489 and 606 mAhg{sup −1} after 180 cycles when cycled at room temperature in a 3.0–0.01 V potential (vs. Li/Li{sup +}) window at current density of 100 mAg{sup −1}, respectively, which are much higher than that of graphite (375 mAhg{sup −1}) under the same current density. Although the anodes in sodium ion batteries showed poorer specific capability than that in lithium-ion batteries, they still achieve a reversible sodium intercalation capacity of 122 and 139 mAhg{sup −1} with similar cycling stability. The feature of stable cycling performance makes the biomass carbon derived from natural ramie fibers and corncobs to be promising candidates as electrodes in rechargeable sodium-ion batteries and lithium-ion batteries.

  13. Sodium vapor deposition onto a horizontal flat plate above liquid sodium surface, (3)

    International Nuclear Information System (INIS)

    Kudo, Kazuhiko; Hirata, Masaru.

    1978-01-01

    Sodium vapour and sodium mist in the cover gas of a sodium system of a fast breeder reactor cause various problems. In this report, with the results of measurements of sodium mist concentration, the distribution of sodium mist diameter in cover gas was analytically obtained. The analysis was made by using the different nucleus model B. The measurement of the concentration of sodium mist was carried out with a sodium mist pot designed by the author. The experiment was done at the sodium temperature of 400 and 500 degree centigrade. The relations among sodium temperature, upper wall temperature, and the sodium mist concentration in cover gas were obtained. Evaluation of effective condensed nuclear radius in the cover gas was made by the comparison of analysis and experimental results. The results of this evaluation shows the following conclusions. It is impossible to express the distribution of sodium mist diameter by normal distribution or logarithmic normal distribution. Drop of sodium temperature results in the decrease of weight mean radius of generated sodium mist. Drop of upper wall temperature causes the decrease of weight mean radius, and increases sodium mist concentration. (Kato, T.)

  14. Three-dimensional iron sulfide-carbon interlocked graphene composites for high-performance sodium-ion storage

    DEFF Research Database (Denmark)

    Huang, Wei; Sun, Hongyu; Shangguan, Huihui

    2018-01-01

    Three-dimensional (3D) carbon-wrapped iron sulfide interlocked graphene (Fe7S8@C-G) composites for high-performance sodium-ion storage are designed and produced through electrostatic interactions and subsequent sulfurization. The iron-based metal–organic frameworks (MOFs, MIL-88-Fe) interact with...

  15. Electrochemical Performance of Electrospun carbon nanofibers as free-standing and binder-free anodes for Sodium-Ion and Lithium-Ion Batteries

    International Nuclear Information System (INIS)

    Jin, Juan; Shi, Zhi-qiang; Wang, Cheng-yang

    2014-01-01

    Highlights: • Electrospun carbon nanofiber webs were prepared by pyrolysis of polyacrylonitrile. • The webs as binder-free and current collector-free electrodes for SIBs and LIBs. • Different layer spacing and pore size for Li and Na lead different electrochemical behavior. • Electrochemical performances of the electrodes were high. - Abstract: A series of hard carbon nanofiber-based electrodes derived from electrospun polyacrylonitrile (PAN) nanofibers (PAN-CNFs) have been fabricated by stabilization in air at about 280 °C and then carbonization in N 2 at heat treatment temperatures (HTT) between 800 and 1500 °C. The electrochemical performances of the binder-free, current collector-free carbon nanofiber-based anodes in lithium-ion batteries and sodium-ion batteries are systematically investigated and compared. We demonstrate the presence of similar alkali metal insertion mechanisms in both cases, but just the differences of the layer spacing and pore size available for lithium and sodium ion lead the discharge capacity delivered at sloping region and plateau region to vary from the kinds of alkali elements. Although the anodes in sodium-ion batteries show poorer rate capability than that in lithium-ion batteries, they still achieve a reversible sodium intercalation capacity of 275 mAh g −1 and similar cycling stability due to the conductive 3-D network, weakly ordered turbostratic structure and a large interlayer spacing between graphene sheets. The feature of high capacity and stable cycling performance makes PAN-CNFs to be promising candidates as electrodes in rechargeable sodium-ion batteries and lithium-ion batteries

  16. Influence of concentration, time and method of application of citric acid and sodium citrate in root conditioning

    Science.gov (United States)

    CAVASSIM, Rodrigo; LEITE, Fábio Renato Manzolli; ZANDIM, Daniela Leal; DANTAS, Andrea Abi Rached; RACHED, Ricardo Samih Georges Abi; SAMPAIO, José Eduardo Cezar

    2012-01-01

    Objective The aim of this study was to establish the parameters of concentration, time and mode of application of citric acid and sodium citrate in relation to root conditioning. Material and Methods A total of 495 samples were obtained and equally distributed among 11 groups (5 for testing different concentrations of citric acid, 5 for testing different concentrations of sodium citrate and 1 control group). After laboratorial processing, the samples were analyzed under scanning electron microscopy. A previously calibrated and blind examiner evaluated micrographs of the samples. Non-parametric statistical analysis was performed to analyze the data obtained. Results Brushing 25% citric acid for 3 min, promoted greater exposure of collagen fibers in comparison with the brushing of 1% citric acid for 1 minute and its topical application at 1% for 3 min. Sodium citrate exposed collagen fibers in a few number of samples. Conclusion Despite the lack of statistical significance, better results for collagen exposure were obtained with brushing application of 25% citric acid for 3 min than with other application parameter. Sodium citrate produced a few number of samples with collagen exposure, so it is not indicated for root conditioning. PMID:22858707

  17. Influence of concentration, time and method of application of citric acid and sodium citrate in root conditioning

    Directory of Open Access Journals (Sweden)

    Rodrigo Cavassim

    2012-06-01

    Full Text Available OBJECTIVES: The aim of this study was to establish the parameters of concentration, time and mode of application of citric acid and sodium citrate in relation to root conditioning. MATERIAL AND METHODS: A total of 495 samples were obtained and equally distributed among 11 groups (5 for testing different concentrations of citric acid, 5 for testing different concentrations of sodium citrate and 1 control group. After laboratorial processing, the samples were analyzed under scanning electron microscopy. A previously calibrated and blind examiner evaluated micrographs of the samples. Non-parametric statistical analysis was performed to analyze the data obtained. RESULTS: Brushing 25% citric acid for 3 min, promoted greater exposure of collagen fibers in comparison with the brushing of 1% citric acid for 1 minute and its topical application at 1% for 3 min. Sodium citrate exposed collagen fibers in a few number of samples. CONCLUSION: Despite the lack of statistical significance, better results for collagen exposure were obtained with brushing application of 25% citric acid for 3 min than with other application parameter. Sodium citrate produced a few number of samples with collagen exposure, so it is not indicated for root conditioning.

  18. Experimental and numerical analysis of sodium-carbonate salt gradient solar-pond performance under simulated solar-radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kurt, Hueseyin; Ozkaymak, Mehmet [Zonguldak Karaelmas University, Technical Education Faculty, 78200 Karabuk (Turkey); Binark, A. Korhan [Marmara University, Technical Education Faculty, 34722 Kuyubasi-Istanbul (Turkey)

    2006-04-01

    The objective of this study is to investigate experimentally and theoretically whether sodium carbonate (Na{sub 2}CO{sub 3}) salt is suitable for establishing a salinity gradient in a salt-gradient solar-pond (SGSP). For this purpose, a small-scale prismatic solar-pond was constructed. Experiments were conducted in the laboratory under the incident radiation from two halogen-lamps acting as a solar simulator. Furthermore, a one-dimensional transient mathematical model that describes the heat and mass transfer behaviour of the SGSP was developed. The differential equations obtained were solved numerically using a finite-difference method. It was found from the experiments that the density gradient, achieved using sodium carbonate salt, can suppress convection from the bottom to the surface of the pond. (author)

  19. Experimental and numerical analysis of sodium-carbonate salt gradient solar-pond performance under simulated solar-radiation

    International Nuclear Information System (INIS)

    Kurt, Hueseyin; Ozkaymak, Mehmet; Binark, A. Korhan

    2006-01-01

    The objective of this study is to investigate experimentally and theoretically whether sodium carbonate (Na 2 CO 3 ) salt is suitable for establishing a salinity gradient in a salt-gradient solar-pond (SGSP). For this purpose, a small-scale prismatic solar-pond was constructed. Experiments were conducted in the laboratory under the incident radiation from two halogen-lamps acting as a solar simulator. Furthermore, a one-dimensional transient mathematical model that describes the heat and mass transfer behaviour of the SGSP was developed. The differential equations obtained were solved numerically using a finite-difference method. It was found from the experiments that the density gradient, achieved using sodium carbonate salt, can suppress convection from the bottom to the surface of the pond

  20. An investigation of sodium iodide solubility in sodium-stainless steel systems

    International Nuclear Information System (INIS)

    Sagawa, Norihiko; Tashiro, Suguru

    1996-01-01

    Sodium iodide and major constituents of stainless steel in sodium are determined by using the steel capsules to obtain a better understanding on contribution of the constituents to the apparent iodide solubility in sodium. The capsule loaded with 20 g sodium and 0.1 - 0.3 g powder of sodium iodide is heated at its upper part in a furnace and cooled at its bottom on brass plates to establish a large temperature gradient along the capsule tube. After a given period of equilibration, the iodide and constituents are fixed in solidified sodium by quick quenching of the capsules. Sodium samples are taken from the sectioned capsule tube and submitted to sodium dissolution by vaporized water for determination of the iodine and to vacuum distillation for determination of the metal elements. Iron and nickel concentrations are observed to be lower in the samples at higher iodine concentrations. Chromium and manganese concentrations are seen to be insensitive to the iodine concentrations. The observations can be interpreted by a model that sodium oxide combines with metal iodide in sodium to form a complex compound and with consideration that the compound will fall and deposit onto the bottom of the capsule by thermal diffusion. (author)

  1. A novel method of non-violent dissolution of sodium metal in a concentrated aqueous solution of Epsom salt

    International Nuclear Information System (INIS)

    Lakshmanan, A.R.; Prasad, M.V.R.; Ponraju, D.; Krishnan, H.

    2004-01-01

    A new technique of non-violent and fast dissolution of sodium metal in a concentrated aqueous solution of Epsom salt (MgSO 4 .7H 2 O) at room temperature (RT) has been developed. The dissolution process is mildly exothermic but could be carried out even in a glass beaker in air under swift stirring condition. The reaction products consist of mixed salts of MgSO 4 and Na 2 SO 4 as well as Mg(OH) 2 which are only mildly alkaline and hence are non-corrosive and non-hazardous unlike NaOH. A 50 mL solution having Epsom salt concentration of 2 M was found to give the optimal composition for disposal of 1 g of sodium. Supersaturated (>2.7 M), as well as dilute (<1.1 M) solutions, however, cause violent reactions and hence should be avoided. Repeated sodium dissolution in Epsom solution produced a solid waste of 4.7 g per g of sodium dissolved which is comparable with the waste (4 g) produced in 8 M NaOH solution. A 1.4 M Epsom solution sprayed with a high-pressure jet cleaner at RT in air easily removed the sodium blocked inside a metal pipe made of mild steel. The above jet also dissolved peacefully residual sodium collected on the metal tray after a sodium fire experiment. No sodium fire or explosion was observed during this campaign. The Epsom solution spray effectively neutralized the minor quantity of sodium aerosol produced during this campaign. This novel technique would hence be quite useful for draining sodium from fast breeder reactor components and bulk processing of sodium as well as for sodium fire fighting

  2. Reduction of deoxynivalenol in barley by treatment with aqueous sodium carbonate and heat.

    Science.gov (United States)

    Abramson, David; House, James D; Nyachoti, C Martin

    2005-11-01

    Naturally contaminated lots of Canadian barley containing either 18.4 or 4.3 microg/g deoxynivalenol (DON) were heated at 80 degrees C, with small amounts of water or 1 M sodium carbonate solution to study the rate of DON reduction. Samples were heated in sealed polypropylene containers for periods of up to 8 days. In the 18.4 microg/g DON barley, rapid reductions were observed: with no solutions added, DON declined to 14.7 microg/g after 1 day, and to 4.9 microg/g after 8 days solely due to heat; with water at 10 mL/100 g barley, DON levels reached 3.7 microg/g after 8 days; with 1 M sodium carbonate solution added at 10 mL/100 g barley, DON declined to 4.7 microg/g after 1 day, and to 0.4 microg/g after 8 days; with 20 mL/100 g barley, DON declined to 1.4 microg/g after 1 day and to near-zero levels after 8 days. In the 4.3 microg/g DON barley, more gradual reductions were evident: with no solutions added, DON declined to 2.9 microg/g after 8 days solely due to heat; with water at 10 mL/100 g barley, DON levels reached 2.3 microg/g after 8 days; with 1 M sodium carbonate solution added at 10 mL/100 g barley, DON declined to 2.7 microg/g after 1 day, and to near-zero levels after 8 days; with 20 mL/100 g barley, DON declined to 1.4 microg/g after 1 day and to near-zero levels after 3, 5 and 8 days.

  3. Impact of sodium caseinate concentration and location on magnesium release from multiple W/O/W emulsions.

    Science.gov (United States)

    Bonnet, Marie; Cansell, Maud; Placin, Frédéric; Anton, Marc; Leal-Calderon, Fernando

    2010-06-15

    Water-in-oil-in-water (W/O/W) double emulsions were prepared and the rate of release of magnesium ions from the internal to the external aqueous phase was followed. Sodium caseinate was used not only as a hydrophilic surface-active species but also as a chelating agent able to bind magnesium ions. The release occurred without film rupturing (no coalescence). The kinetics of the release process depended on the location (in only one or in both aqueous compartments) and on the concentration of sodium caseinate. The rate of release increased with the concentration of sodium caseinate in the external phase and decreased when sodium caseinate was present in the inner droplets. The experiments were interpreted within the frame of a mean-field model based on diffusion, integrating the effect of ion binding. The data could be adequately fitted by considering a time-dependent permeation coefficient of the magnesium ions across the oil phase. Our results suggested that ion permeability was influenced by the state of the protein interfacial layers which itself depended on the extent of magnesium binding.

  4. Study of sodium combustion and fire extinction by pulverized substances. Role of additives

    International Nuclear Information System (INIS)

    Reuillon, Marcelline.

    1976-01-01

    A study is presented on inflammation and combustion of liquid sodium, extinction of the metal fires by comburant concentration reducing and cooling, liquid covering, powder smothering. The role of the additives is discussed. The setting up and the experimental process are given. The sodium combustion residues are analyzed. Various powder mixtures based on alkaline carbonates, NaCl-Na 2 CO 3 , NaCl-Na 2 CO 3 ,H 2 O etc... are studied. An attempt of interpretation on sodium fire extinction is presented [fr

  5. Unusual Passivation Ability of Superconcentrated Electrolytes toward Hard Carbon Negative Electrodes in Sodium-Ion Batteries.

    Science.gov (United States)

    Takada, Koji; Yamada, Yuki; Watanabe, Eriko; Wang, Jianhui; Sodeyama, Keitaro; Tateyama, Yoshitaka; Hirata, Kazuhisa; Kawase, Takeo; Yamada, Atsuo

    2017-10-04

    The passivation of negative electrodes is key to achieving prolonged charge-discharge cycling with Na-ion batteries. Here, we report the unusual passivation ability of superconcentrated Na-salt electrolytes. For example, a 50 mol % sodium bis(fluorosulfonyl)amide (NaFSA)/succinonitrile (SN) electrolyte enables highly reversible Na + insertion into a hard carbon negative electrode without any electrolyte additive, functional binder, or electrode pretreatment. Importantly, an anion-derived passivation film is formed via preferential reduction of the anion upon charging, which can effectively suppress further electrolyte reduction. As a structural characteristic of the electrolyte, most anions are coordinated to multiple Na + cations at high concentration, which shifts the lowest unoccupied molecular orbitals of the anions downward, resulting in preferential anion reduction. The present work provides a new understanding of the passivation mechanism with respect to the coordination state of the anion.

  6. Concentrations of chloride and sodium in groundwater in New Hampshire from 1960 through 2011

    Science.gov (United States)

    Medalie, Laura

    2013-01-01

    Several studies from the 1970s and more recently (for example, Hall (1975), Daley and others (2009) and Mullaney (2009)) have found that concentrations of chloride and sodium in groundwater in New Hampshire have increased during the past 50 years. Increases likely are related to road salt and other anthropogenic sources, such as septic systems, wastewater, and contamination from landfills and salt-storage areas. According to water-quality data reported to the New Hampshire Department of Environmental Services (NHDES), about 100 public water systems (5 percent) in 2010 had at least one groundwater sample with chloride concentrations that were equal to or exceeded the U.S. Environmental Protection Agency (USEPA) secondary maximum contaminant level (SMCL) of 250 mg/L before the water was treated for public consumption. The SMCL for chloride is a measurement of potential cosmetic or aesthetic effects of chloride in water. High concentrations of chloride and sodium in drinking-water sources can be costly to remove.

  7. Investigation of Plugging of Narrow Sodium Channels by Sodium and Carbon Dioxide Interaction

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sun Hee; Wi, Myung-Hwan; Min, Jae Hong; Kim, Tae-joon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    The supercritical CO{sub 2} Brayton cycle system is known to be a promising power conversion system for improving the efficiency and preventing the sodium water reaction (SWR) of the current SFR concept using a Rankine steam cycle. PCHEs are known to have potential for reducing the volume occupied by the sodium-to-CO{sub 2} exchangers as well as the heat exchanger mass relative to traditional shell-and-tube heat exchangers. Here, we report a study on a plugging test by the interaction of sodium and CO{sub 2} to investigate design parameters of sodium channels in the realistic operating conditions. We investigated a plugging test by an interaction of sodium and CO{sub 2} with different cross sectional areas of the sodium channels. It was found that the flow rate of sodium decreased earlier and faster with a narrower cross sectional area compared to a wider one. Our experimental results are expected to be used for determining the sodium channel areas of PCHEs.

  8. Early Jurassic Carbon and Sodium Sequestration in a CAMP basalt flow

    Science.gov (United States)

    Block, K. A.; Puffer, J. H.

    2017-12-01

    The initial HTQ-type CAMP Orange Mountain Basalt flow, as well as related pillowed flows and the overlying Preakness flows, locally underwent substantial and well documented albitization, chloritization, and sulphate, carbonate, and zeolite mineralization. Layers representing at least 25 vol % of the Orange Mountain Basalt have undergone a major net increase in sodium and carbon content and a major redistribution of magnesium and calcium. Most alteration occurred during the development of a widespread early Jurassic geothermal system similar to the active system of Iceland. In both cases alteration was controlled by active circulation of basin brines through vesicular layers during rapid burial at temperatures that were kept elevated by recurring magmatism. Whole rock Na2O levels typically increased from 2.2 wt. % in unaltered layers to 3.2 wt. % in vesicular layers, and commonly reached levels exceeding 5 wt. %. The environmental implications of the removal of such massive amounts of sodium from the geothermal system on the chlorine budget and the salt content of Early Jurassic lakes are currently being evaluated. Massive amounts of carbon sequestration from the geothermal system may have mitigated an increased burden on the early Jurassic atmosphere where geothermal CO2 may have otherwise been vented at hot springs or solfataras. Calcite amygdules typically account for 5 to 10 vol. % of the vesiculated layers amounting to 66 to 132 kg of CO2 per m3 of basalt. If 25 vol. % of the 160 thick Orange Mountain Basalt is vesiculated that would equate to about 2640 to 5280 kg of CO2 per m2 of basalt. The full extent of calcite enrichment across the entire CAMP province, however, has not yet been determined.

  9. Correlations between ANP concentrations in atria, plasma and cerebral structures and sodium chloride preference in Wistar rats

    Directory of Open Access Journals (Sweden)

    Glass H.

    1997-01-01

    Full Text Available We determined whether ANP (atrial natriuretic peptide concentrations, measured by radioimmunoassay, in the ANPergic cerebral regions involved in regulation of sodium intake and excretion and pituitary gland correlated with differences in sodium preference among 40 Wistar male rats (180-220 g. Sodium preference was measured as mean spontaneous ingestion of 1.5% NaCl solution during a test period of 12 days. The relevant tissues included the olfactory bulb (OB, the posterior and anterior lobes of the pituitary gland (PP and AP, respectively, the median eminence (ME, the medial basal hypothalamus (MBH, and the region anteroventral to the third ventricle (AV3V. We also measured ANP content in the right (RA and left atrium (LA and plasma. The concentrations of ANP in the OB and the AP were correlated with sodium ingestion during the preceding 24 h, since an increase of ANP in these structures was associated with a reduced ingestion and vice-versa (OB: r = -0.3649, P<0.05; AP: r = -0.3291, P<0.05. Moreover, the AP exhibited a correlation between ANP concentration and mean NaCl intake (r = -0.4165, P<0.05, but this was not the case for the OB (r = 0.2422. This suggests that differences in sodium preference among individual male rats can be related to variations of AP ANP level. Earlier studies indicated that the OB is involved in the control of NaCl ingestion. Our data suggest that the OB ANP level may play a role mainly in day-to-day variations of sodium ingestion in the individual rat

  10. One-step microwave synthesis of photoluminescent carbon nanoparticles from sodium dextran sulfate water solution

    Science.gov (United States)

    Kokorina, Alina A.; Goryacheva, Irina Y.; Sapelkin, Andrei V.; Sukhorukov, Gleb B.

    2018-04-01

    Photoluminescent (PL) carbon nanoparticles (CNPs) have been synthesized by one-step microwave irradiation from water solution of sodium dextran sulfate (DSS) as the sole carbon source. Microwave (MW) method is very simple and cheap and it provides fast synthesis of CNPs. We have varied synthesis time for obtaining high luminescent CNPs. The synthesized CNPs exhibit excitation-dependent photoluminescent. Final CNPs water solution has a blue- green luminescence. CNPs have low cytotoxicity, good photostability and can be potentially suitable candidates for bioimaging, analysis or analytical tests.

  11. Correlation of the concentration of the carbon-associated radiation damage levels with the total carbon concentration in silicon

    Energy Technology Data Exchange (ETDEWEB)

    Ferenczi, G.; Londos, C.A.; Pavelka, T.; Somogyi, M.; Mertens, A.

    1988-01-01

    The dominant carbon-related radiation damage center in silicon was studied in detail by deep level transient spectroscopy. Samples with different carbon and oxygen content were implanted with gradually increasing proton fluence. Two energetically closely spaced levels were revealed and tentative identities were assigned. One at E/sub T/+E/sub V/ = 0.344 eV (sigma/sub p/ = 1.1 x 10/sup -16/ cm/sup 2/) is assigned as the C+O/sub i/ complex, and that at E/sub T/+E/sub V/ = 0.370 eV (sigma/sub p/ = 8 x 10/sup -18/ cm/sup 2/) is assigned as the C/sub s/-Si/sub i/-C/sub s/ complex. It was shown that the concentration of these defects is correlated to the total concentration of carbon in the crystal.

  12. Efficacy of Sodium Carbonate Peroxyhydrate as A Catfish Egg Disinfectant and Comparison to Hydrogen Peroxide

    Science.gov (United States)

    Two experiments were conducted to evaluate the efficacy of sodium carbonate peroxyhydrate (SCP) for improving channel catfish Ictalurus punctatus hatching success when used as a prophylactic chemotherapeutant during egg incubation. In the first experiment, efficacy of SCP was evaluated in 379-L, al...

  13. The geochemical evolution of aqueous sodium in the Black Creek Aquifer, Horry and Georgetown counties, South Carolina

    Science.gov (United States)

    Zack, Allen L.; Roberts, Ivan

    1988-01-01

    The Black Creek aquifer contains dilute seawater near the North Carolina State line, probably the result of incomplete flushing of ancient seawater. Data do not indicate that the dilute seawater has migrated toward areas of fresh ground-water withdrawals. The concentration of chloride in ground-water samples ranges from 5 to 720 milligrams per liter and that of sodium from 160 to 690 milligrams per liter. Ion-exchange reactions (sodium for calcium and fluoride for hydroxyl) occur with the calcium carbonate dissolution reaction which produces calcium, bicarbonate, and hydroxyl ions. The reaction sequence and stoichiometry result in an aqueous solution in which the sum of bicarbonate and chloride equivalents per liter is equal to the equivalents per liter of sodium. Calcium ions are exchanged for sodium ions derived from sodium-rich clays upgradient of the dilute seawater. The cation-exchange reaction equilibrates at a sodium concentration of 280 milligrams per liter. Amounts of sodium greater than 280 milligrams per liter are contributed from dilute seawater. The cation-exchange reaction approaches an equilibrium which represents a mass-action limit in terms of the ratio of sodium to calcium in solution versus the ratio of exchangeable sodium to calcium on clay surfaces. Where the limit of calcium carbonate solubility is approached and dissolution ceases, some precipitation of calcite probably takes place. The dissolution of calcite exposes fossil shark teeth which release fluoride ions to the ground water through anion exchange with aqueous hydroxyl ions.

  14. New Silica Magnetite Sorbent: The Influence of Variations of Sodium Silicate Concentrations on Silica Magnetite Character

    Science.gov (United States)

    Azmiyawati, C.; Pratiwi, P. I.; Darmawan, A.

    2018-04-01

    The adsorption capacity of an adsorbent is determined by the adsorbent and the adsorbate properties. The character of the adsorbent will play a major role in its ability to adsorb the corresponding adsorbate. Therefore, in this study we looked at the effects of variations of sodium silicate concentrations on the resulting magnetite silica adsorbent properties. The application of silica coating on the magnetite was carried out through a sol-gel process with sodium silicate and HCl precursors. Based on the characterization data obtained, it was found that the silica coating on magnetite can increase the resistance to acid leaching, increase the particle size, but decrease the magnetic properties of the magnetite. Based on Gas Sorption Analyzer (GSA) and X-ray Difraction (XRD) data it can successively be determined that increase in concentration of sodium silicate will increase the surface area and amorphous structure of the Silica Magnetie.

  15. Interpretation of postmortem vitreous concentrations of sodium and chloride.

    Science.gov (United States)

    Zilg, B; Alkass, K; Berg, S; Druid, H

    2016-06-01

    Vitreous fluid can be used to analyze sodium and chloride levels in deceased persons, but it remains unclear to what extent such results can be used to diagnose antemortem sodium or chloride imbalances. In this study we present vitreous sodium and chloride levels from more than 3000 cases. We show that vitreous sodium and chloride levels both decrease with approximately 2.2mmol/L per day after death. Since potassium is a well-established marker for postmortem interval (PMI) and easily can be analyzed along with sodium and chloride, we have correlated sodium and chloride levels with the potassium levels and present postmortem reference ranges relative the potassium levels. We found that virtually all cases outside the reference range show signs of antemortem hypo- or hypernatremia. Vitreous sodium or chloride levels can be the only means to diagnose cases of water or salt intoxication, beer potomania or dehydration. We further show that postmortem vitreous sodium and chloride strongly correlate and in practice can be used interchangeably if analysis of one of the ions fails. It has been suggested that vitreous sodium and chloride levels can be used to diagnose drowning or to distinguish saltwater from freshwater drowning. Our results show that in cases of freshwater drowning, vitreous sodium levels are decreased, but that this mainly is an effect of postmortem diffusion between the eye and surrounding water rather than due to the drowning process, since the decrease in sodium levels correlates with immersion time. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. The various sodium purification techniques

    International Nuclear Information System (INIS)

    Courouau, J.L.; Masse, F.; Rodriguez, G.; Latge, C.; Redon, B.

    1997-01-01

    In the framework of sodium waste treatment, the sodium purification phase plays an essential role in the chain of operations leading to the transformation of the active sodium, considered as waste, into a stable sodium salt. The objectives of the purification operations are: To keep a low impurity level, particularly a low concentration in oxygen and hydrogen, in order to allow its transfer to a processing plant, and in order to avoid risks of plugging and/or corrosion in sodium facilities; To reduce the sodium activity in order to limit the dose rate close to the facilities, and in order to reduce the activity of the liquid and gaseous effluents. After a recall of the different kind of impurities that can be present in sodium, and of the different purification methods that could be associated with, the following points are highlighted: (i) Oxygen and hydrogen purification needs, and presentation of some selection criteria for a purification unit adapted to a sodium processing plant, as well as 2 cold trap concepts that are in accordance with these criteria: PSICHOS and PIRAMIDE. (ii) Tritium reduction in a bulk of liquid sodium by swamping, isotopic exchange, or permeation throughout a membrane. (iii) Caesium trapping on carbonaceous matrix. The main matrices used at present are R.V.C. (Reticulated Vitreous Carbon) and Actitex/Pica products. Tests in the laboratory and on an experimental device have demonstrated the performances of these materials, which are able to reduce sodium activity in Cs 134 and Cs 137 to very low values. The sodium purification processes as regards to the hydrogen, oxygen and caesium, that are aimed at facilitating the subsequent treatment of sodium, are therefore mastered operations. Regarding the operations associated with the reduction of the tritium activity, the methods are in the process of being qualified, or to be qualified. (author)

  17. Shift in aggregation, ROS generation, antioxidative defense, lysozyme and acetylcholinesterase activities in the cells of an Indian freshwater sponge exposed to washing soda (sodium carbonate).

    Science.gov (United States)

    Mukherjee, Soumalya; Ray, Mitali; Ray, Sajal

    2016-09-01

    Washing soda, chemically identified as anhydrous sodium carbonate, is a popular cleaning agent among the rural and urban populations of India which often contaminates the freshwater ponds and lakes, the natural habitat of sponge Eunapius carteri. Present investigation deals with estimation of cellular aggregation, generation of ROS and activities of antioxidant enzymes, lysozyme and acetylcholinesterase in the cells of E. carteri under the environmentally realistic concentrations of washing soda. Prolonged treatment of washing soda inhibited the degree of cellular aggregation. Experimental exposure of 8 and 16mg/l of sodium carbonate for 48h elevated the physiological level of reactive oxygen species (ROS) generation in the agranulocytes, semigranulocytes and granulocytes of E. carteri, whereas, treatment of 192h inhibited the ROS generation in three cellular morphotypes. Activities of superoxide dismutase, catalase and glutathione-S-transferase were recorded to be inhibited under prolonged exposure of washing soda. Washing soda mediated inhibition of ROS generation and depletion in the activities of antioxidant enzymes were indicative to an undesirable shift in cytotoxic status and antioxidative defense in E. carteri. Inhibition in the activity of lysozyme under the treatment of sodium carbonate was suggestive to a severe impairment of the innate immunological efficiency of E. carteri distributed in the washing soda contaminated habitat. Washing soda mediated inhibition in the activity of acetylcholinesterase indicated its neurotoxicity in E. carteri. Washing soda, a reported environmental contaminant, affected adversely the immunophysiological status of E. carteri with reference to cellular aggregation, oxidative stress, antioxidative defense, lysozyme and acetylcholinesterase activity. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. The sodium process facility at Argonne National Laboratory - West

    International Nuclear Information System (INIS)

    Michelbacher, J.A.; Henslee, S.P.; McDermott, M.D.; Price, J.R.; Rosenberg, K.E.; Wells, P.B.

    1997-01-01

    Argonne National Laboratory - West (ANL-W) has approximately 680,000 liters (180,000 gallons) of raw sodium stored in facilities on site. As mandated by the State of Idaho and the United States Department of Energy (DOE), this sodium must be transformed into a stable condition for land disposal. To comply with this mandate, ANL-W designed and built the Sodium Process Facility (SPF) for the processing of this sodium into a dry, sodium carbonate powder. The major portion of the sodium stored at ANL-W is radioactively contaminated. The SPF was designed to react elemental sodium to sodium carbonate through two-stages involving caustic process and carbonate process steps. The sodium is first reacted to sodium hydroxide in the caustic process step. The caustic process step involves the injection of sodium into a nickel reaction vessel filled with a 50 wt% solution of sodium hydroxide. Water is also injected, controlling the boiling point of the solution. In the carbonate process, the sodium hydroxide is reacted with carbon dioxide to form sodium carbonate. This dry powder, similar in consistency to baking soda, is a waste form acceptable for burial in the State of Idaho as a non-hazardous, radioactive waste. The caustic process was originally designed and built in the 1980s for reacting the 290,000 liters (77,000 gallons) of primary sodium from the Fermi-1 Reactor to sodium hydroxide. The hydroxide was slated to be used to neutralize acid products from the PUREX process at the Hanford site. However, changes in the DOE mission precluded the need for hydroxide and the caustic process was never operated. With the shutdown of the Experimental Breeder Reactor-II (EBR-II), the necessity for a facility to react sodium was identified. In order to comply with Resource Conservation and Recovery Act (RCRA) requirements, the sodium had to be converted into a waste form acceptable for disposal in a Sub-Title D low-level radioactive waste disposal facility. Sodium hydroxide is a RCRA

  19. Influence of sodium silicate concentration on structural and tribological properties of microarc oxidation coatings on 2017A aluminum alloy substrate

    International Nuclear Information System (INIS)

    Polat, Aytekin; Makaraci, Murat; Usta, Metin

    2010-01-01

    In this paper, thick and hard oxide coatings resistant to wear were produced on 2017A-T6 Al alloy by the microarc oxidation (MAO) technique in an alkali electrolyte consisting of different sodium silicate concentrations (0-8 g/l). The coatings were characterized by means of optical microscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and surface profilometry. Microhardness, scratch adhesion and pin-on-disk sliding wear tests were also performed to evaluate the tribological properties of the coatings. The influence of sodium silicate concentration on the structural and tribological properties of the MAO coatings was discussed. Results reveal that increasing sodium silicate concentration from 0 to 8 g/l in the electrolyte caused an increase in the electrolyte conductivity (from 7.71 to 18.1 mS/cm) and a decrease in positive final voltage (from 627 to 590 V) in the MAO process. In response to the increase in sodium silicate concentration, the thickness, surface roughness (R a ) and critical load (L c ) corresponding to adhesive failure of the coatings were increased simultaneously from 74 to 144 μm, and 4.4 to 6.58 μm, and 127.76 to 198.54 N, respectively. At the same time, the phase structure and composition of the coatings also varied by the participation of silicate ions in the reactions and their incorporation into the coating structure. Moreover, it was observed that the coating formed in the low sodium silicate concentration (4 g/l) had higher surface hardness (2020 HV) and improved wear resistance than the one (1800 HV) formed in the high sodium silicate concentration (8 g/l). The coatings produced in three different electrolytic solutions provided an excellent wear resistance and a load carrying capacity compared to the uncoated aluminum alloy.

  20. High quality bio-oil from catalytic flash pyrolysis of lignocellulosic biomass over alumina-supported sodium carbonate

    KAUST Repository

    Imran, Ali; Bramer, Eddy A.; Seshan, Kulathuiyer; Brem, Gerrit

    2014-01-01

    Performance of a novel alumina-supported sodium carbonate catalyst was studied to produce a valuable bio-oil from catalytic flash pyrolysis of lignocellulosic biomass. Post treatment of biomass pyrolysis vapor was investigated in a catalyst fixed

  1. Carbon dioxide concentrations are very high in developing oilseeds.

    Science.gov (United States)

    Goffman, Fernando D; Ruckle, Mike; Ohlrogge, John; Shachar-Hill, Yair

    2004-09-01

    A new method has been developed to rapidly determine the total inorganic carbon concentration (gaseous [CO2] + aqueous [CO(2)] + [HCO3-] + [CO3(2)-]) in developing seeds. Seeds are rapidly dissected and homogenized in 1 N HCl in gas-tight vials. The headspace gas is then analyzed by infrared gas analysis. Developing rapeseed (Brassica napus L.) and soybean [Glycine max (L.) Merr.] seeds were analyzed and found to have up to 40 and 12 mM total inorganic carbon, respectively. These concentrations are ca. 600-2000-fold higher than in ambient air or values reported for leaves. Carbon dioxide concentrations in rapeseed peaked during the stage of maximum oil synthesis and declined as seeds matured. The consequences for seed metabolism, physiology and carbon economy are discussed.

  2. Carbon monoxide and COHb concentration in blood in various circumstances

    Energy Technology Data Exchange (ETDEWEB)

    Modic, J. [Faculty of Mechanical Engineering, University of Ljubljana, Ljubljana (Slovenia)

    2003-07-01

    On the basis of known medical experiments we find out the correlation between the concentration of carbon monoxide (CO) in inhaling air and the concentration of carboxihemoglobyne (COHb) in human blood. All internal combustion engines produce exhaust gases containing noxious compounds: carbon monoxide, nitrogen oxides (NO{sub x}), carbon oxides (CxHy) and smoke. In a living room is important the smoke of cigarettes, smoke of furnaces, improper ventilation. In tunnel is most dangerous the carbon monoxide if it exceeds an allowable level. In human blood the carbon monoxide causes increasing the concentration of carboxihemoglobyne and in this case the hypoxia of web. With help of mathematical model the concentrations of some dangerous substances at the end of tunnel were calculated. For this case a differential equation also was developed and it shows the correlation between concentration of carbon monoxide in the air and concentration of carboxihemoglobyne in the blood. The constructed mathematical model shows circumstances in the tunnel (velocity of air moving as effect of induction, concentration of noxious substances and criterial number). Also a corresponding computer program was developed, which makes possible a quick and simple calculation. All the results are proved by experiments. Finally the differential equation was done, which shows a temporal connection between both parameters as a function of tunnel characteristics. (author)

  3. Preliminary Plugging tests in Narrow Sodium Channels by Sodium and Carbon Dioxide reaction

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sun Hee; Wi, Myung-Hwan; Min, Jae Hong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    This report is on the investigation of the physical/chemical phenomena that a slow loss of CO{sub 2} inventory into sodium after the sodium-CO{sub 2} boundary failure in PCHEs in realistic operating conditions. The first phenomenon is potential channel plugging inside the narrow PCHE channel. Unlike a conventional shell and- tube type HXs, failures in a PCHE are expected to be small cracks. If the faulted channel is blocked, it may have a positive function for plant safety because the pressure boundary would automatically recover due to this self-plugging. The other one is damage propagation on pressure boundary, which is referred to as potential wastage with combined corrosion/erosion effect. Physical/chemical phenomena that a slow loss of CO{sub 2} inventory into sodium after the sodium-CO{sub 2} boundary failure in printed circuit heat exchangers (PCHEs) were investigated. Our preliminary experimental results of plugging show that sodium flow immediately stopped as CO{sub 2} was injected through the nozzle at 300-400 .deg. C in 3 mm sodium channels, whereas sodium flow stopped about 60 min after CO{sub 2} injection in 5 mm sodium channels.

  4. Obtain of uranium concentrates from fertil liquids

    International Nuclear Information System (INIS)

    Narvaez Castillo, W.A.

    1992-01-01

    This research tried to encounter the form to remove uranium from the rock in the best way, for that it was used different process like leaching, extraction, concentration and precipitation. To leach the mineral was chosen basic leaching, using a mixture of carbonate-sodium bicarbonate, this method is more adequated for the basic nature of the mineral. In extraction was used specific uranium ionic interchanges, so was chosen a tertiary amine like Alamina 336. The concentration phase is intimately binding with the extraction by ionic interchange, for the capability of resine's extraction to obtain concentrated liquids. When the liquids were obtained with high concentration of uranium in the same time were purified and then were precipitated, for that we employed a precipitant agent like: Sodium hydroxide, Amonium hydroxide, Magnesium hydroxide, Hydrogen peroxide and phosphates. With all concentrates we obtain the YELLOW CAKE

  5. Single Sodium Pyruvate Ingestion Modifies Blood Acid-Base Status and Post-Exercise Lactate Concentration in Humans

    Directory of Open Access Journals (Sweden)

    Robert A. Olek

    2014-05-01

    Full Text Available This study examined the effect of a single sodium pyruvate ingestion on a blood acid-base status and exercise metabolism markers. Nine active, but non-specifically trained, male subjects participated in the double-blind, placebo-controlled, crossover study. One hour prior to the exercise, subjects ingested either 0.1 g·kg−1 of body mass of a sodium pyruvate or placebo. The capillary blood samples were obtained at rest, 60 min after ingestion, and then three and 15 min after completing the workout protocol to analyze acid-base status and lactate, pyruvate, alanine, glucose concentrations. The pulmonary gas exchange, minute ventilation and the heart rate were measured during the exercise at a constant power output, corresponding to ~90% O2max. The blood pH, bicarbonate and the base excess were significantly higher after sodium pyruvate ingestion than in the placebo trial. The blood lactate concentration was not different after the ingestion, but the post-exercise was significantly higher in the pyruvate trial (12.9 ± 0.9 mM than in the placebo trial (10.6 ± 0.3 mM, p < 0.05 and remained elevated (nonsignificant after 15 min of recovery. The blood pyruvate, alanine and glucose concentrations, as well as the overall pulmonary gas exchange during the exercise were not affected by the pyruvate ingestion. In conclusion, the sodium pyruvate ingestion one hour before workout modified the blood acid-base status and the lactate production during the exercise.

  6. Thermogravimetric study of rare earth concentrates

    International Nuclear Information System (INIS)

    Delyagejd, V.V.; Anisimova, V.N.; Eremenko, Z.V.; Kutsev, V.S.

    1974-01-01

    Methods of thermogravimetric, chemical and phase analysis were used in measuring the concentration of rare-earth elements of different origins. At temperatures 400-800 deg C a gradual decomposition of fluorocarbonates takes place leading to the formation of derivatives of corresponding oxides and oxyfluorides. For concentrates containing siderite the process takes place at 550-600 deg C followed by oxidation of bivalent iron into trivalent state. Reaction of rare-earth elements with sodium carbonate and the increase in the concentration of the latter results in a narrowing down of the interval of temperatures at which decomposition takes place. Under these conditions an intense reaction and a fusion take place leading to the formation of eutectic at 500-600 deg C and further synthesis of sodium fluoride and oxyfluoride derivatives of calcium and rare-earth elements

  7. Three-Dimensional SnS Decorated Carbon Nano-Networks as Anode Materials for Lithium and Sodium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Yanli Zhou

    2018-02-01

    Full Text Available The three-dimensional (3D SnS decorated carbon nano-networks (SnS@C were synthesized via a facile two-step method of freeze-drying combined with post-heat treatment. The lithium and sodium storage performances of above composites acting as anode materials were investigated. As anode materials for lithium ion batteries, a high reversible capacity of 780 mAh·g−1 for SnS@C composites can be obtained at 100 mA·g−1 after 100 cycles. Even cycled at a high current density of 2 A·g−1, the reversible capacity of this composite can be maintained at 610 mAh·g−1 after 1000 cycles. The initial charge capacity for sodium ion batteries can reach 333 mAh·g−1, and it retains a reversible capacity of 186 mAh·g−1 at 100 mA·g−1 after 100 cycles. The good lithium or sodium storage performances are likely attributed to the synergistic effects of the conductive carbon nano-networks and small SnS nanoparticles.

  8. Stability of sodium bicarbonate injection 8.4% in syringes over a six-week period in refrigerated temperature.

    Science.gov (United States)

    Seki, Jack T; Wang, Tian Q; Yip, Paul M; Mazzulli, Tony; Minden, Mark D

    2018-04-01

    Background Dysfunctional central venous catheter prohibits the administration of potential life-saving chemotherapy and the delivery of essential supportive care needs to patients. Sodium bicarbonate injection has been shown to impede against fibrin clot formation and prolong prothrombin time and thrombin clotting time. Sodium bicarbonate injection has been tried as a second-line agent with good results in a small number of patients (internal data not published) when alteplase failed. We assessed whether the pre-filled sodium bicarbonate injection in 5 mL syringes would not only preserve sterility and retain its pH and concentration but also amount to the potential cost savings for future use when stored in a refrigerated environment. Methodology Twelve pre-filled 5 mL syringes were prepared aseptically, of which four each were tested for pH, sodium bicarbonate injection concentration and sterility when stored in refrigerated temperature over a six-week period. A standard pH meter, enzymatic carbon dioxide analyzer, and a 14-day incubation for microbial detection were employed for this study. Results Sodium bicarbonate concentration measured in the form of carbon dioxide ranged from 923 mmol/L or (1846 mosol/L) to 1006 mmol/L or (2012 mosmol/L), and pH ranged from (7.88 to 8.05) were reported over the duration of the study period. The 14-day incubation period resulted in no microbial growth. Conclusion Our study results have indicated that the pH and sodium bicarbonate injection concentration values were stable and within range, comparable to those reported by the manufacturer within the study period. The contents of the subdivided sodium bicarbonate injection 5 mL syringes retained sterility over a 14-day incubation period.

  9. Changes in plasma potassium concentration during carbon dioxide pneumoperitoneum

    DEFF Research Database (Denmark)

    Perner, A; Bugge, K; Lyng, K M

    1999-01-01

    Hyperkalaemia with ECG changes had been noted during prolonged carbon dioxide pneumoperitoneum in pigs. We have compared plasma potassium concentrations during surgery in 11 patients allocated randomly to undergo either laparoscopic or open appendectomy and in another 17 patients allocated randomly...... to either carbon dioxide pneumoperitoneum or abdominal wall lifting for laparoscopic colectomy. Despite an increasing metabolic acidosis, prolonged carbon dioxide pneumoperitoneum resulted in only a slight increase in plasma potassium concentrations, which was both statistically and clinically insignificant....... Thus hyperkalaemia is unlikely to develop in patients with normal renal function undergoing carbon dioxide pneumoperitoneum for laparoscopic surgery....

  10. Restraining Sodium Volatilization in the Ferric Bauxite Direct Reduction System

    Directory of Open Access Journals (Sweden)

    Wentao Hu

    2016-03-01

    Full Text Available Direct reduction is an emerging utilization technology of ferric bauxite. However, it requires much more sodium carbonate than ordinary bauxite does. The volatilization is one of the most significant parts of sodium carbonate consumption, as reported in previous studies. Based on the new direct reduction method for utilization of ferric bauxite, this paper has systematically investigated factors including heating temperature, heating time, and sodium carbonate dosage influencing sodium volatilization. For the purpose of reducing sodium volatilization, the Box–Benhken design was employed, and the possibility of separating iron and sodium after direct reduction was also investigated.

  11. Deficiency of Carbonic Anhydrase II Results in a Urinary Concentrating Defect

    Directory of Open Access Journals (Sweden)

    Devishree Krishnan

    2018-01-01

    Full Text Available Carbonic anhydrase II (CAII is expressed along the nephron where it interacts with a number of transport proteins augmenting their activity. Aquaporin-1 (AQP1 interacts with CAII to increase water flux through the water channel. Both CAII and aquaporin-1 are expressed in the thin descending limb (TDL; however, the physiological role of a CAII-AQP1 interaction in this nephron segment is not known. To determine if CAII was required for urinary concentration, we studied water handling in CAII-deficient mice. CAII-deficient mice demonstrate polyuria and polydipsia as well as an alkaline urine and bicarbonaturia, consistent with a type III renal tubular acidosis. Natriuresis and hypercalciuria cause polyuria, however, CAII-deficient mice did not have increased urinary sodium nor calcium excretion. Further examination revealed dilute urine in the CAII-deficient mice. Urinary concentration remained reduced in CAII-deficient mice relative to wild-type animals even after water deprivation. The renal expression and localization by light microscopy of NKCC2 and aquaporin-2 was not altered. However, CAII-deficient mice had increased renal AQP1 expression. CAII associates with and increases water flux through aquaporin-1. Water flux through aquaporin-1 in the TDL of the loop of Henle is essential to the concentration of urine, as this is required to generate a concentrated medullary interstitium. We therefore measured cortical and medullary interstitial concentration in wild-type and CAII-deficient mice. Mice lacking CAII had equivalent cortical interstitial osmolarity to wild-type mice: however, they had reduced medullary interstitial osmolarity. We propose therefore that reduced water flux through aquaporin-1 in the TDL in the absence of CAII prevents the generation of a maximally concentrated medullary interstitium. This, in turn, limits urinary concentration in CAII deficient mice.

  12. Effect of Elevated Carbon Dioxide Concentration on Carbon Assimilation under Fluctuating Light

    Czech Academy of Sciences Publication Activity Database

    Holišová, Petra; Zitová, Martina; Klem, Karel; Urban, Otmar

    2012-01-01

    Roč. 41, č. 6 (2012), s. 1931-1938 ISSN 0047-2425 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA ČR(CZ) GAP501/10/0340; GA MŠk(CZ) LM2010007; GA AV ČR IAA600870701 Institutional support: RVO:67179843 Keywords : carbon * light * beech * spruce * carbon assimilation * elevat e carbon * dioxide concentration * mol * photosynthetic * assimilation * carbon dioxide * dioxide * concentracion * leave * photosynthetic efficiency Subject RIV: EH - Ecology, Behaviour Impact factor: 2.353, year: 2012

  13. Novel star-like surfactant as dispersant for multi-walled carbon nanotubes in aqueous suspensions at high concentration

    Science.gov (United States)

    Qiao, Min; Ran, Qianping; Wu, Shishan

    2018-03-01

    A kind of novel surfactant with star-like molecular structure and terminated sulfonate was synthesized, and it was used as the dispersant for multi-walled carbon nanotubes (CNTs) in aqueous suspensions compared with a traditional single-chained surfactant. The star-like surfactant showed good dispersing ability for multi-walled CNTs in aqueous suspensions. Surface tension analysis, total organic carbon analysis, X-ray photoelectron spectroscopy, zeta potential, dynamic light scattering and transmission electron microscopy were performed to research the effect of star-like surfactant on the dispersion of multi-walled CNTs in aqueous suspensions. With the assistance of star-like surfactant, the CNTs could disperse well in aqueous suspension at high concentration of 50 g/L for more than 30 days, while the CNTs precipitated completely in aqueous suspension after 1 day without any dispersant or after 10 days with sodium 4-dodecylbenzenesulfonic acid as dispersant.

  14. 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

  15. Elucidating the Role of Carbon Sources on Abiotic and Biotic Release of Arsenic into Cambodian Aquifers

    Science.gov (United States)

    Koeneke, M.

    2017-12-01

    Arsenic (As) is a naturally occurring contaminant in Cambodia that has been contaminating well-water sources of millions of people. Commonly, studies look into the biotic factors that cause the arsenic to be released from aquifer sediments to groundwater. However, abiotic release of As from sediments, though little studied, may also play key roles in As contamination of well water. The goal of this research is to quantitatively compare organic-carbon mediated abiotic and biotic release of arsenic from sediments to groundwater. Batch anaerobic incubation experiments under abiotic (sodium azide used to immobilize microbes) and biotic conditions were conducted using Cambodian aquifer sediments, four different organic carbon sources (sodium lactate, sodium citrate, sodium oxalate, and humic acid), and six different carbon concentrations (0, 1, 2.5, 5, 10, 25mg C/L). Dissolved arsenic, iron(Fe), and manganese(Mn) concentrations in the treatments were measured 112 days . In addition, sediment and solution carbon solution was measured . Collectively, these show how different carbon sources, different carbon concentrations, and how abiotic and biotic factors impact the release of arsenic from Cambodian sediments into aquifers. Overall, an introduction of organic carbon to the soil increases the amount of As released from the sediment. The biotic + abiotic and abiotic conditions seemed to play a minimal role in the amount of As released. Dissolved species analysis showed us that 100% of the As was As(V), Our ICP-MS results vary due to the heterogeneity of samples, but when high levels are Fe are seen in solution, we also see high levels of As. We also see higher As concentrations when there is a smaller amount of Mn in solution.

  16. Carbon-concentrating mechanisms in seagrasses.

    Science.gov (United States)

    Larkum, Anthony William D; Davey, Peter A; Kuo, John; Ralph, Peter J; Raven, John A

    2017-06-01

    Seagrasses are unique angiosperms that carry out growth and reproduction submerged in seawater. They occur in at least three families of the Alismatales. All have chloroplasts mainly in the cells of the epidermis. Living in seawater, the supply of inorganic carbon (Ci) to the chloroplasts is diffusion limited, especially under unstirred conditions. Therefore, the supply of CO2 and bicarbonate across the diffusive boundary layer on the outer side of the epidermis is often a limiting factor. Here we discuss the evidence for mechanisms that enhance the uptake of Ci into the epidermal cells. Since bicarbonate is plentiful in seawater, a bicarbonate pump might be expected; however, the evidence for such a pump is not strongly supported. There is evidence for a carbonic anhydrase outside the outer plasmalemma. This, together with evidence for an outward proton pump, suggests the possibility that local acidification leads to enhanced concentrations of CO2 adjacent to the outer tangential epidermal walls, which enhances the uptake of CO2, and this could be followed by a carbon-concentrating mechanism (CCM) in the cytoplasm and/or chloroplasts. The lines of evidence for such an epidermal CCM are discussed, including evidence for special 'transfer cells' in some but not all seagrass leaves in the tangential inner walls of the epidermal cells. It is concluded that seagrasses have a CCM but that the case for concentration of CO2 at the site of Rubisco carboxylation is not proven. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  17. Assessment of sodium status in large ruminants by measuring the sodium-to-potassium ratio in muzzle secretions.

    Science.gov (United States)

    Singh, S P; Rani, D

    1999-09-01

    To develop a simple diagnostic test to assess sodium status in large ruminants on the basis of the sodium-to-potassium ratio (Na:K) and to determine its relevance. 7 buffalo heifers and 21 lactating, pregnant, and nonpregnant dairy cows and heifers. Buffalo heifers were subjected in 2 experiments to variable dietary sodium intake or sodium depletion and changes in sodium and potassium concentrations; Na:K was simultaneously monitored in various body fluids to study its value for indicating sodium status. Validity of the muzzle secretion test was assessed. Muzzle secretion and urinary Na:K and sodium concentration, but not serum electrolyte concentrations, reflected the sodium status of buffalo heifers in response to the widely variable intake of sodium (0.03 to 0.16% of dry matter [DM]). Progressive sodium depletion during an 11-day period, using saliva deprivation caused reciprocal changes in sodium and potassium concentrations in saliva and muzzle secretion, but not in urine. Decreasing urine sodium concentration was associated with decreasing urine potassium concentration. Saliva, urine, and muzzle secretion Na:K closely reflected the degree of sodium deficit. Buffaloes or dairy cows maintained on optimal sodium intake had muzzle secretion and urine Na:K > 0.30. Muzzle secretion or urine Na:K muzzle secretion Na:K, and to a large extent urine Na:K, may be used as a convenient diagnostic tool to assess sodium status in large ruminants. It has accuracy similar to that of saliva Na:K.

  18. Influence of antihypertensive therapy, sodium intake and the concentration of potassium in plasma on concentration of aldosterone and plasma renin activity

    Directory of Open Access Journals (Sweden)

    Lalić Tijana

    2013-01-01

    Full Text Available Introduction: Primary aldosteronism (PA is a group of disorders which are characterized by inadequate and non-suppressible production of aldosterone. The prevalence of PA is increasing in hypertensive population. The golden standard of screening for primary aldosteronism, determination of aldosterone/plasma renin activity (ARR, is influenced by numerous exogenous and endogenous factors. Testing cannot always be conducted under optimal conditions. Objective: To determine influence of antihypertensive drugs and concentrations of potassium and sodium in blood and urine on values of aldosterone and plasma renin activity. Methods: In this retrospective study, we analyzed medical reports of patients admitted to Department of thyroid gland disease in the period from 2009 to 2011, with increased risk for primary aldosteronism. Body weight and height, sodium and potassium in serum and urine, plasma aldosterone concentrations and plasma renin activity, data on medicines and comorbidity were analyzed in all patients. In processing data, statistical methods descriptive analysis, Student T test and univariate linear regression were applied. Result: Of 137 patients, there were more patients with resistant hypertension (53,28% than with adrenal tumors (46,72%. Most patients used calcium channel blockers. Treatment with alpha blockers and calcium channel blockers does not influence ARR. Beta blockers and ACE inhibitors can influence ARR and diuretics and vasodilatators have definite influence. Diabetes mellitus can have higher risk of false negative results. Urine sodium excretion is significantly correlated with plasma aldosteron and serum potassium. Plasma aldosteron and PRA are significantly correlated with concentrations of electrolites in urine. Conclusion: Increased prevalence of primary aldosteronism necessitates need for accurate and better diagnostics.

  19. Changes in sodium and uric acid concentrations in plasma during the menstrual cycle.

    Science.gov (United States)

    Mira, M; Stewart, P M; Gebski, V; Llewellyn-Jones, D; Abraham, S F

    1984-03-01

    Hormonal changes during the menstrual cycle are well documented, but many other biochemical variables have not been studied. We find that in the luteal phase of the menstrual cycle the concentrations of sodium and uric acid are significantly lower. The changes may be of significance for the determination of the normal reference interval.

  20. Evaluation of sampling methods for measuring exposure to volatile inorganic acids in workplace air. Part 2: Sampling capacity and breakthrough tests for sodium carbonate-impregnated filters.

    Science.gov (United States)

    Demange, Martine; Oury, Véronique; Rousset, Davy

    2011-11-01

    In France, the MétroPol 009 method used to measure workplace exposure to inorganic acids, such as HF, HCl, and HNO3, consists of a closed-face cassette fitted with a prefilter to collect particles, and two sodium carbonate-impregnated filters to collect acid vapor. This method was compared with other European methods during the development of a three-part standard (ISO 21438) on the determination of inorganic acids in workplace air by ion chromatography. Results of this work, presented in a companion paper, led to a need to go deeper into the performance of the MétroPol 009 method regarding evaluation of the breakthrough of the acids, both alone and in mixtures, interference from particulate salts, the amount of sodium carbonate required to impregnate the sampling filter, the influence of sampler components, and so on. Results enabled improvements to be made to the sampling device with respect to the required amount of sodium carbonate to sample high HCl or HNO3 concentrations (500 μL of 5% Na2CO3 on each of two impregnated filters). In addition, a PVC-A filter used as a prefilter in a sampling device showed a propensity to retain HNO3 vapor so a PTFE filter was considered more suitable for use as a prefilter. Neither the material of the sampling cassette (polystyrene or polypropylene) nor the sampling flowrate (1 L/min or 2 L/min) influenced the performance of the sampling device, as a recovery of about 100% was achieved in all experiments for HNO3, HCl, and HF, as well as HNO3+HF and HNO3+HCl mixtures, over a wide range of concentrations. However, this work points to the possibility of interference between an acid and salts of other acids. For instance, interference can occur through interaction of HNO3 with chloride salts: the stronger the acid, the greater the interference. Methods based on impregnated filters are reliable for quantitative recovery of inorganic volatile acids in workplace atmosphere but are valuable only in the absence of interferents.

  1. Skin Sodium Concentration Correlates with Left Ventricular Hypertrophy in CKD.

    Science.gov (United States)

    Schneider, Markus P; Raff, Ulrike; Kopp, Christoph; Scheppach, Johannes B; Toncar, Sebastian; Wanner, Christoph; Schlieper, Georg; Saritas, Turgay; Floege, Jürgen; Schmid, Matthias; Birukov, Anna; Dahlmann, Anke; Linz, Peter; Janka, Rolf; Uder, Michael; Schmieder, Roland E; Titze, Jens M; Eckardt, Kai-Uwe

    2017-06-01

    The pathogenesis of left ventricular hypertrophy in patients with CKD is incompletely understood. Sodium intake, which is usually assessed by measuring urinary sodium excretion, has been inconsistently linked with left ventricular hypertrophy. However, tissues such as skin and muscle may store sodium. Using 23 sodium-magnetic resonance imaging, a technique recently developed for the assessment of tissue sodium content in humans, we determined skin sodium content at the level of the calf in 99 patients with mild to moderate CKD (42 women; median [range] age, 65 [23-78] years). We also assessed total body overhydration (bioimpedance spectroscopy), 24-hour BP, and left ventricular mass (cardiac magnetic resonance imaging). Skin sodium content, but not total body overhydration, correlated with systolic BP ( r =0.33, P =0.002). Moreover, skin sodium content correlated more strongly than total body overhydration did with left ventricular mass ( r =0.56, P skin sodium content is a strong explanatory variable for left ventricular mass, unaffected by BP and total body overhydration. In conclusion, we found skin sodium content to be closely linked to left ventricular mass in patients with CKD. Interventions that reduce skin sodium content might improve cardiovascular outcomes in these patients. Copyright © 2017 by the American Society of Nephrology.

  2. EFFECTS OF SODIUM AND CALCIUM IN LIGNITE ON THE PERFORMANCE OF ACTIVATED CARBON PRODUCTS; TOPICAL

    International Nuclear Information System (INIS)

    Edwin S. Olson; Kurt E. Eylands; Daniel J. Stepan

    2001-01-01

    New federal drinking water regulations have been promulgated to restrict the levels of disinfection by-products (DBPs) in finished public water supplies. DBPs are suspected carcinogens and are formed when organic material is partially oxidized by disinfectants commonly used in the water treatment industry. Additional federal mandates are expected in the near future that will also affect public water suppliers with respect to DBPs. These new federal drinking water regulations may require public water suppliers to adjust treatment practices or incorporate additional treatment operations into their existing treatment trains. Many options have been identified, including membrane processes, granular activated carbon, powered activated carbon (PAC), enhanced coagulation and/or softening, and alternative disinfectants (e.g., chlorine dioxide, ozone, and chloramines). Of the processes being considered, PAC appears to offer an attractive benefit-to-cost advantage for many water treatment plants, particularly small systems (those serving fewer than 10,000 customers). PAC has traditionally been used by the water treatment industry for the removal of compounds contributing to taste and odor problems. PAC also has the potential to remove naturally occurring organic matter (NOM) from raw waters prior to disinfection, thus controlling the formation of regulated DBPs. Many small water systems are currently using PAC for taste and odor control and have the potential to use PAC for controlling DBPs. Activated carbons can be produced from a variety of raw materials, including wood, peat, coconut husks, and numerous types of coal. The Energy and Environmental Research Center (EERC) has been working on the development of a PAC product to remove NOM from surface water supplies to prevent the formation of carcinogenic DBPs during chlorination. During that study, the sodium and calcium content of the lignites showed a significant effect on the sorption capacity of the activated carbon

  3. Effects of sodium carbonate and sodium bicarbonate on yield and characteristics of Pacific white shrimp (Litopenaeus vannamei).

    Science.gov (United States)

    Chantarasuwan, C; Benjakul, S; Visessanguan, W

    2011-08-01

    Effects of sodium carbonate (Na2CO3) and sodium bicarbonate (NaHCO3) on yield and characteristics of Pacific white shrimp (Litopenaeus vannamei) were studied. Shrimp soaked in 2.5% NaCl containing both compounds at different levels of pH (5.5, 7, 8.5, 10 and 11.5) showed an increase in the weight gain and cooking yield and a reduced cooking loss as pH of solutions increased (p<0.05). Increases in pH and salt content in soaked shrimp muscle were obtained with increasing pH (p<0.05). Higher pH of soaking solution partially solubilized proteins in the muscle as well as carotenoproteins. pH of solutions above 8.5 led to the pronounced leaching of pigments, associated with the lowered redness of cooked shrimp. Shear force of raw and cooked shrimp continuously decreased as pH of solution increased (p<0.05). Solution containing 2.5% NaCl and 2.0% NaHCO3 (pH 8.5) was recommended for treatment of white shrimp as a promising alternative for phosphates to increase the yield and to lower cooking loss without any negative effect on sensory properties.

  4. Eliminating radium from uranium mill acid effluent with barium chloride-sodium carbonate precipitation

    International Nuclear Information System (INIS)

    Xiao Jiayuan

    1998-01-01

    The eliminating radium procedure, barium chloride-sodium carbonate-sand filtering, being used, radium can be eliminated to 3.7 x 10 -2 Bq/L order of magnitude from uranium mill acid effluents which contain 3.7 Bq/L Ra and pH 6∼9 when Ba 2+ is added by 3∼5 mg per litre, Na 2 CO 3 5mg. The radium elimination rate is more than 90%

  5. High quality bio-oil from catalytic flash pyrolysis of lignocellulosic biomass over alumina-supported sodium carbonate

    NARCIS (Netherlands)

    Ali Imran, A.; Bramer, Eduard A.; Seshan, Kulathuiyer; Brem, Gerrit

    2014-01-01

    Performance of a novel alumina-supported sodium carbonate catalyst was studied to produce a valuable bio-oil from catalytic flash pyrolysis of lignocellulosic biomass. Post treatment of biomass pyrolysis vapor was investigated in a catalyst fixed bed reactor at the downstream of the pyrolysis

  6. Enhancement of total lipid yield by nitrogen, carbon, and iron supplementation in isolated microalgae.

    Science.gov (United States)

    Sivaramakrishnan, Ramachandran; Incharoensakdi, Aran

    2017-08-01

    The biochemical contents and biodiesel production ability of three microalgal strains grown under different sodium nitrate, sodium carbonate, and ferric ammonium citrate (iron) levels were investigated. The highest biomass and lipid contents were found in Scenedesmus sp., Chlorella sp., and Chlamydomonas sp. when grown in normal BG-11 containing sodium carbonate concentration at 0.03 g · L -1 , and in normal BG-11 containing iron concentration (IC) at 0.009 or 0.012 g · L -1 . Increasing the sodium nitrate level increased the biomass content, but decreased the lipid content in all three microalgae. Among the three microalgae, Scenedesmus sp. showed the highest total lipid yield of 0.69 g · L -1 under the IC of 0.012 g · L -1 . Palmitic and oleic acids were the major fatty acids of Scenedesmus sp. and Chlamydomonas sp. lipids. On the other hand, Chlorella sp. lipids were rich in palmitic, oleic, and linolenic acids, and henceforth contributing to poor biodiesel properties below the standard limits. The three isolated strains had a potential for biodiesel production. Nevertheless, Scenedesmus sp. from stone quarry pond water was the most suitable source for biodiesel production with tolerance toward the high concentration of sodium carbonate without the loss of its biodiesel properties. © 2017 Phycological Society of America.

  7. Effect of sodium chloride concentration on elemental analysis of brines by laser-induced breakdown spectroscopy (LIBS).

    Science.gov (United States)

    Goueguel, Christian; Singh, Jagdish P; McIntyre, Dustin L; Jain, Jinesh; Karamalidis, Athanasios K

    2014-01-01

    Leakage of injected carbon dioxide (CO2) or resident fluids, such as brine, is a major concern associated with the injection of large volumes of CO2 into deep saline formations. Migration of brine could contaminate drinking water resources by increasing their salinity or endanger vegetation and animal life as well as human health. The main objective of this study was to investigate the effect of sodium chloride (NaCl) concentration on the detection of calcium and potassium in brine samples using laser-induced breakdown spectroscopy (LIBS). The ultimate goals were to determine the suitability of the LIBS technique for in situ measurements of metal ion concentrations in NaCl-rich solution and to develop a chemical sensor that can provide the early detection of brine intrusion into formations used for domestic or agricultural water production. Several brine samples of NaCl-CaCl2 and NaCl-KCl were prepared at NaCl concentrations between 0.0 and 3.0 M. The effect of NaCl concentration on the signal-to-background ratio (SBR) and signal-to-noise ratio (SNR) for calcium (422.67 nm) and potassium (769.49 nm) emission lines was evaluated. Results show that, for a delay time of 300 ns and a gate width of 3 μs, the presence of and changes in NaCl concentration significantly affect the SBR and SNR for both emission lines. An increase in NaCl concentration from 0.0 to 3.0 M produced an increase in the SNR, whereas the SBR dropped continuously. The detection limits obtained for both elements were in the milligrams per liter range, suggesting that a NaCl-rich solution does not severely limit the ability of LIBS to detect trace amount of metal ions.

  8. Structural and surface functionality changes in reticulated vitreous carbon produced from poly(furfuryl alcohol) with sodium hydroxide additions

    Energy Technology Data Exchange (ETDEWEB)

    Oishi, Silvia Sizuka, E-mail: silviaoishi@uol.com.br [LAS, Instituto Nacional de Pesquisas Espaciais (INPE), Av. dos Astronautas 1758, São José dos Campos, SP 12227-010 (Brazil); Botelho, Edson Cocchieri [Departamento de Materiais e Tecnologia, Univ Estadual Paulista (UNESP), Av. Doutor Ariberto Pereira da Cunha 333, Guaratinguetá, SP 12516-410 (Brazil); Rezende, Mirabel Cerqueira [Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo (UNIFESP), Rua Talim 330, São José dos Campos, SP 12231-280 (Brazil); Ferreira, Neidenêi Gomes [LAS, Instituto Nacional de Pesquisas Espaciais (INPE), Av. dos Astronautas 1758, São José dos Campos, SP 12227-010 (Brazil)

    2017-02-01

    Highlights: • Reticulated vitreous carbon (RVC) was processed from poly(furfuryl alcohol) with different amounts of NaOH. • A correlation between microstructure and surface functionalities was proposed. • The structural ordering was mainly influenced by the cured PFA polymerization degree and carboxylic acid content on RVC surface. - Abstract: The use of sodium hydroxide to neutralize the acid catalyst increases the storage life of poly(furfuryl alcohol) (PFA) resin avoiding its continuous polymerization. In this work, a concentrated sodium hydroxide solution (NaOH) was added directly to the PFA resin in order to minimize the production of wastes generated when PFA is washed with diluted basic solution. Thus, different amounts of this concentrated basic solution were added to the resin up to reaching pH values of around 3, 5, 7, and 9. From these four types of modified PFA two sample sets of reticulated vitreous carbon (RVC) were processed and heat treated at two different temperatures (1000 and 1700 °C). A correlation among cross-link density of PFA and RVC morphology, structural ordering and surface functionalities was systematically studied using Fourier transform infrared spectroscopy, scanning electron microscopy, Raman spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy techniques. The PFA neutralization (pH 7) led to its higher polymerization degree, promoting a crystallinity decrease on RVC treated at 1000 °C as well as its highest percentages of carboxylic groups on surface. A NaOH excess (pH 9) substantially increased the RVC oxygen content, but its crystallinity remained similar to those for samples from pH 3 and 5 treated at 1000 °C, probably due to the reduced presence of carboxylic group and the lower polymerization degree of its cured resin. Samples with pH 3 and 5 heat treated at 1000 and 1700 °C can be considered the most ordered which indicated that small quantities of NaOH may be advantageous to minimize continuous

  9. Yttrium and lanthanum recovery from low cerium carbonate, yttrium carbonate and yttrium concentrate

    International Nuclear Information System (INIS)

    Vasconcelos, Mari Estela de

    2006-01-01

    In this work, separation, enrichment and purification of lanthanum and yttrium were performed using as raw material a commercial low cerium rare earth concentrate named LCC (low cerium carbonate), an yttrium concentrate named 'yttrium carbonate', and a third concentrated known as 'yttrium earths oxide. The first two were industrially produced by the late NUCLEMON - NUCLEBRAS de Monazita e Associados Ltda, using Brazilian monazite. The 'yttrium earths oxide' come from a process for preparation of lanthanum during the course of the experimental work for the present thesis. The following techniques were used: fractional precipitation with urea; fractional leaching of the LCC using ammonium carbonate; precipitation of rare earth peroxycarbonates starting from the rare earth complex carbonates. Once prepared the enriched rare earth fractions the same were refined using the ion exchange chromatography with strong cationic resin without the use of retention ion and elution using the ammonium salt of ethylenediaminetetraacetic acid. With the association of the above mentioned techniques were obtained pure oxides of yttrium (>97,7%), lanthanum (99,9%), gadolinium (96,6%) and samarium (99,9%). The process here developed has technical and economic viability for the installation of a large scale unity. (author)

  10. Estimating 24-hour urinary sodium excretion from casual urinary sodium concentrations in Western populations

    DEFF Research Database (Denmark)

    Brown, Ian J; Dyer, Alan R; Chan, Queenie

    2013-01-01

    High intakes of dietary sodium are associated with elevated blood pressure levels and an increased risk of cardiovascular disease. National and international guidelines recommend reduced sodium intake in the general population, which necessitates population-wide surveillance. We assessed the util...

  11. Green synthesis of graphitic carbon nitride nanodots using sodium chloride template

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Bo [National University of Defense Technology, College of Science (China); Zou, Xianshuai; Yan, Tingnan; Fei, Junjie [Xiangtan University, College of Chemistry (China); Chu, Zengyong, E-mail: chuzy@nudt.edu.cn [National University of Defense Technology, College of Science (China)

    2016-05-15

    Graphitic carbon nitride (g-C{sub 3}N{sub 4}) nanodots are simply prepared by a thermal treatment of dicyandiamide (DCDA) confined within NaCl templates. Cyano groups are introduced to the nanodots due to the catalytic effect of NaCl. NaCl could facilitate the polymerization of DCDA at lower temperatures, but will promote the decomposition when the temperature is above 550 °C. Thermal treatment at 600 °C for 30 min is the optimal condition for the scalable synthesis of g-C{sub 3}N{sub 4} nanodots with an average diameter of ~9 nm. g-C{sub 3}N{sub 4} nanodots have a higher band gap of 3.1 eV, which can emit bright blue light due to the decreased diameter, the introduction of cyano groups, and the incorporation of some sodium ions. The residue sodium ions and the cyano groups might lead to the local distortion of the graphitic crystals, or act as recombination centers for the enhanced photoluminescence.Graphical Abstract.

  12. Electrochemical corrosion behavior of A 516 steel using corrosive environments with varying concentrations of sodium thiosulphate

    International Nuclear Information System (INIS)

    Karim, F.; Arif, M.; Reza, I.; Akram, M.; Hussain, N.; Ali, L.

    2012-01-01

    The corrosion behavior of A 516 steel was studied by potentiodynamic polarization technique. Environment used for these tests was sodium chloride (5%), acetic acid (0.5%) and sodium thiosulphate with varying concentration from 0.001 M to 1 M. Surface study was also carried out using optical microscope. The potentiodynamic polarization results revealed the formation of large number of pits in the sample, which was tested in the solution containing NaCl. Pitting corrosion study of alloy A516 G-70 was also conducted to see the effect of different concentrations of thiosulfate with or without addition of NaCl and acetic acid at room temperature. It was observed that different thiosulfate concentrations did not produce any difference in the polarization behavior of the alloys, when added in 5% NaCl and 0.5% acetic acid solution. However, in the absence of NaCl and acetic acid, thiosulfate concentration 0.001 mol/l or higher did produce general corrosion and pitting in the alloy at room temperature is shown.(Orig./A.B.)

  13. Solution chemistry of carbonate minerals and its effects on the flotation of hematite with sodium oleate

    Science.gov (United States)

    Li, Dong; Yin, Wan-zhong; Xue, Ji-wei; Yao, Jin; Fu, Ya-feng; Liu, Qi

    2017-07-01

    The effects of carbonate minerals (dolomite and siderite) on the flotation of hematite using sodium oleate as a collector were investigated through flotation tests, supplemented by dissolution measurements, solution chemistry calculations, zeta-potential measurements, Fourier transform infrared (FTIR) spectroscopic studies, and X-ray photoelectron spectroscopy (XPS) analyses. The results of flotation tests show that the presence of siderite or dolomite reduced the recovery of hematite and that the inhibiting effects of dolomite were stronger. Dissolution measurements, solution chemistry calculations, and flotation tests confirmed that both the cations (Ca2+ and Mg2+) and CO3 2- ions dissolved from dolomite depressed hematite flotation, whereas only the CO3 2- ions dissolved from siderite were responsible for hematite depression. The zeta-potential, FTIR spectroscopic, and XPS analyses indicated that Ca2+, Mg2+, and CO3 2- (HCO3 -) could adsorb onto the hematite surface, thereby hindering the adsorption of sodium oleate, which was the main reason for the inhibiting effects of carbonate minerals on hematite flotation.

  14. MoS{sub 2}/cotton-derived carbon fibers with enhanced cyclic performance for sodium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiang [School of Materials Science and Engineering, Guangdong Provincial Key Laboratory of Advanced Energy Storage Materials, South China University of Technology, Guangzhou, 510641 (China); Yang, Yan [School of Electrical Engineering, Southwest Jiaotong University, Chengdu, 610031 (China); Liu, Jiangwen; Ouyang, Liuzhang; Liu, Jun; Hu, Renzong [School of Materials Science and Engineering, Guangdong Provincial Key Laboratory of Advanced Energy Storage Materials, South China University of Technology, Guangzhou, 510641 (China); Yang, Lichun, E-mail: mslcyang@scut.edu.cn [School of Materials Science and Engineering, Guangdong Provincial Key Laboratory of Advanced Energy Storage Materials, South China University of Technology, Guangzhou, 510641 (China); Zhu, Min [School of Materials Science and Engineering, Guangdong Provincial Key Laboratory of Advanced Energy Storage Materials, South China University of Technology, Guangzhou, 510641 (China)

    2017-08-15

    Highlights: • MoS{sub 2} nanosheets vertically grow on cotton-derived carbon microfibers. • The carbon fibers facilitate charge transfer and structure stabilization. • The MoS{sub 2}/CDCFs exhibit enhanced cyclic performance for reversible Na{sup +} storage. - Abstract: Carbon fibers derived from bio-template are low cost and environmental benign, therefore have attracted much attention in energy storage materials. In this work, we successfully fabricated MoS{sub 2}/cotton-derived carbon fibers (MoS{sub 2}/CDCFs) via hydrothermal route followed by carbonization process. In the composite of MoS{sub 2}/CDCFs, MoS{sub 2} nanosheets vertically grow on the carbon fibers which offer fast ways for electron transfer and at the same time act as robust support to buffer the volume changes of MoS{sub 2} nanosheets during discharge/charge cycles. As anode materials for sodium-ion batteries, MoS{sub 2}/CDCFs exhibit good rate performance and markedly enhanced cyclic stability due to the conductive support of CDCFs. At a current density of 0.1 A g{sup −1}, the MoS{sub 2}/CDCFs-1 shows an initial reversible capacity of 504.9 mAh g{sup −1}, and maintains 444.5 mAh g{sup −1} after 50 cycles. Even when the current density increases to 0.5 A g{sup −1}, it maintains 323.1 mAh g{sup −1} after 150 cycles, which is much higher than the capacity retention of 149.6 mAh g{sup −1} for the bare MoS{sub 2} nanosheets. The improved electrochemical performance verifies the effective strategy of using cotton as carbon source to construct hierarchical composites for sodium-ion batteries.

  15. Investigation of biomass concentration, lipid production, and cellulose content in Chlorella vulgaris cultures using response surface methodology.

    Science.gov (United States)

    Aguirre, Ana-Maria; Bassi, Amarjeet

    2013-08-01

    The microalgae Chlorella vulgaris produce lipids that after extraction from cells can be converted into biodiesel. However, these lipids cannot be efficiently extracted from cells due to the presence of the microalgae cell wall, which acts as a barrier for lipid removal when traditional extraction methods are employed. Therefore, a microalgae system with high lipid productivity and thinner cell walls could be more suitable for lipid production from microalgae. This study addresses the effect of culture conditions, specifically carbon dioxide and sodium nitrate concentrations, on biomass concentration and the ratio of lipid productivity/cellulose content. Optimization of culture conditions was done by response surface methodology. The empirical model for biomass concentration (R(2)  = 96.0%) led to a predicted maximum of 1123.2 mg dw L(-1) when carbon dioxide and sodium nitrate concentrations were 2.33% (v/v) and 5.77 mM, respectively. For lipid productivity/cellulose content ratio (R(2)  = 95.2%) the maximum predicted value was 0.46 (mg lipid L(-1)  day(-1) )(mg cellulose mg biomass(-1) )(-1) when carbon dioxide concentration was 4.02% (v/v) and sodium nitrate concentration was 3.21 mM. A common optimum point for both variables (biomass concentration and lipid productivity/cellulose content ratio) was also found, predicting a biomass concentration of 1119.7 mg dw L(-1) and lipid productivity/cellulose content ratio of 0.44 (mg lipid L(-1)  day(-1) )(mg cellulose mg biomass(-1) )(-1) for culture conditions of 3.77% (v/v) carbon dioxide and 4.01 mM sodium nitrate. The models were experimentally validated and results supported their accuracy. This study shows that it is possible to improve lipid productivity/cellulose content by manipulation of culture conditions, which may be applicable to any scale of bioreactors. Copyright © 2013 Wiley Periodicals, Inc.

  16. Intravitreal flomoxef sodium in rabbits.

    Science.gov (United States)

    Mochizuki, K; Torisaki, M; Yamashita, Y; Komatsu, M; Tanahashi, T

    1993-01-01

    We studied the intraocular concentration of flomoxef sodium in nonvitrectomized and vitrectomized eyes of albino rabbits after intravenous administration of 100 mg/kg flomoxef sodium. The concentration of flomoxef sodium in the vitreous body was undetectable (flomoxef sodium was investigated with ophthalmoscopy, electroretinography (ERG) and light microscopy after intravitreal injection of 200, 500, 1,000 and 2,000 micrograms flomoxef sodium in albino and pigmented rabbits. No ERG changes were induced with 200 micrograms. Other higher doses caused transient ERG changes. After the 200-micrograms injection, the intravitreal concentration decreased exponentially, the half-life being 4.4 h. The antibacterial activity, broad coverage and low intravitreal toxicity of flomoxef sodium suggest that this compound may be used to treat bacterial endophthalmitis.

  17. Characteristic and composition of smokes in sodium fires

    International Nuclear Information System (INIS)

    Goncalves, A.C.; Torres, A.R.; Brito Aghina, L.O. de; Messere e Castro, P.

    1986-01-01

    The formation ratios of chemical principal compounds appear in smokes of fires up to 50 Kg of sodium in installations for fast reactor researches, were measured for a simulation in a scale of 1:1000. Relations of hydroxide concentrations, carbonate and bicarbonate appear in smokes retained in counter-current washing tower and in dry filters are presented. It is still presented the variation of the temperature profile and composition of burning wastes. (Author) [pt

  18. Recovery of gold from arsenopyrite concentrates by cyanidation-carbon adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Heinen, H.J.; McClelland, G.E., Lindstrom, R.E.

    1980-01-01

    The Bureau of Mines, investigated a cyanidation-carbon adsorption technique for extracting gold from arsenopyrite concentrates. Agitation leach experiments were conducted on 85%-minus-35-mesh gravity concentrates containing 21.8 oz gold and 6.4 oz silver per ton. Results obtained in leaching the concentrates showed that 96.9% gold and 90.7% silver extraction could be achieved in 96 hours of agitation. Gold and silver were recovered from the resulting pregnant solution by exposure to granular activated carbon in a countercurrent system. Carbon loadings of 2556 oz of gold and 502 oz of silver per ton were achieved. These loadings are significantly higher than heretofore thought practical.

  19. Effect of tri-sodium citrate concentration on structural, optical and electrical properties of chemically deposited tin sulfide films

    Energy Technology Data Exchange (ETDEWEB)

    Gode, F., E-mail: ftmgode@gmail.com [Department of Physics, Mehmet Akif Ersoy University, 15030 Burdur (Turkey); Guneri, E. [Department of Primary Education, Erciyes University, 38039 Kayseri (Turkey); Baglayan, O. [Department of Physics, Anadolu University, 26470 Eskisehir (Turkey)

    2014-11-01

    Graphical abstract: - Highlights: • SnS thin films grown by CBD in different concentration of tri-sodium citrate. • Grain size increases, while surface roughness decreases, with concentration. • Optical band gap decreases from 1.40 eV to 1.17 eV with increasing concentration. • Electrical conductivity improves with increasing concentration. - Abstract: Tin sulfide thin films were deposited onto glass substrates by chemical bath deposition. The effects of molar concentration of the complexing agent, tri-sodium citrate, on the structural, morphological, optical and electrical properties of the films were investigated. The films are characterized by X-ray diffraction, scanning electron microscopy, atomic force microscopy, optical absorption spectroscopy and Hall effect measurements. Polycrystalline film structure in orthorhombic phase was determined. Flower-like spherical grains are observed on the surface. While their average size increased from 345 nm to 750 nm when the tri-sodium citrate concentration was increased from 6.4 × 10{sup −3} M to 8.0 × 10{sup −3} M, the surface roughness varied in an opposite manner from approximately 120.18 nm to 29.36 nm. For these concentrations, optical band gap of the films decreased from 1.40 eV to 1.17 eV, whereas the Hall conductivity, mobility and carrier concentration of the films increased slightly from 5.91 × 10{sup −5} to 8.78 × 10{sup −5} (Ω cm){sup −1}, from 148 to 228 cm{sup 2} V{sup −1} s{sup −1} and from 1.73 × 10{sup 12} to 3.59 × 10{sup 12} cm{sup −1}, respectively.

  20. Carbon Concentration and Carbon-to-Nitrogen Ratio Influence Submerged-Culture Conidiation by the Potential Bioherbicide Colletotrichum truncatum NRRL 13737

    Science.gov (United States)

    Jackson, Mark A.; Bothast, Rodney J.

    1990-01-01

    We assessed the influence of various carbon concentrations and carbon-to-nitrogen (C:N) ratios on Colletotrichum truncatum NRRL 13737 conidium formation in submerged cultures grown in a basal salts medium containing various amounts of glucose and Casamino Acids. Under the nutritional conditions tested, the highest conidium concentrations were produced in media with carbon concentrations of 4.0 to 15.3 g/liter. High carbon concentrations (20.4 to 40.8 g/liter) inhibited sporulation and enhanced the formation of microsclerotiumlike hyphal masses. At all the carbon concentrations tested, a culture grown in a medium with a C:N ratio of 15:1 produced more conidia than cultures grown in media with C:N ratios of 40:1 or 5:1. While glucose exhaustion was often coincident with conidium formation, cultures containing residual glucose sporulated and those with high carbon concentrations (>25 g/liter) exhausted glucose without sporulation. Nitrogen source studies showed that the levels of C. truncatum NRRL 13737 conidiation were similar for all protein hydrolysates tested. Reduced conidiation occurred when amino acid and inorganic nitrogen sources were used. Of the nine carbon sources evaluated, acetate as the sole carbon source resulted in the lowest level of sporulation. Images PMID:16348348

  1. Evaluation of sodium carbonate peroxyhydrate as a potential catfish egg disinfectant.

    Science.gov (United States)

    Small, Brian C

    2009-06-01

    Two experiments were conducted to evaluate the efficacy of sodium carbonate peroxyhydrate (SCP) in improving the hatching success of channel catfish Ictalurus punctatus when used as a prophylactic chemotherapeutant during egg incubation. In the first experiment, the efficacy of SCP was evaluated in 379-L aluminum incubation troughs similar to those used in commercial hatcheries. Egg masses treated daily with 254 mg of SCP/L of water had significantly higher mean hatching success than untreated controls, and a pathogen-inhibiting effect was also evident (i.e., no gross infection was observed on the treated egg masses). In the second experiment, the hatching success of egg masses treated daily with 254 mg/L was compared with that of egg masses treated daily with hydrogen peroxide (70 mg/L). The effects of both treatments on the pH, dissolved oxygen, and hydrogen peroxide concentrations in the trough were also examined. Both SCP and hydrogen peroxide significantly improved hatching success. Unlike in the treatment with hydrogen peroxide, water pH increased during the treatment with SCP; however, no negative effects on hatching success were observed. The results of this research suggest that SCP acts similarly to hydrogen peroxide in improving channel catfish hatching success and warrants further research to determine whether it could be a practical and effective alternative for managing catfish egg infections in commercial hatcheries.

  2. Concentrated Aqueous Sodium Tosylate as Green Medium for Alkene Oxidation and Nucleophilic Substitution Reactions.

    Science.gov (United States)

    Sela, Tal; Lin, Xiaoxi; Vigalok, Arkadi

    2017-11-03

    A hydrotropic solution of highly concentrated sodium tosylate (NaOTs) can be used as a recyclable medium for the environmentally benign oxidation of conjugated alkenes with H 2 O 2 . Both uncatalyzed and metal-catalyzed reactions provided the corresponding oxidation products in higher yields than in pure water or many common organic solvents.

  3. Sodium setpoint and gradient in bicarbonate hemodialysis.

    Science.gov (United States)

    Basile, Carlo; Libutti, Pasquale; Lisi, Piero; Vernaglione, Luigi; Casucci, Francesco; Losurdo, Nicola; Teutonico, Annalisa; Lomonte, Carlo

    2013-01-01

    The demonstration of an individual osmolar setpoint in hemodialysis (HD) is crucial to individualize dialysate sodium concentrations. Furthermore, the diffusive gradient between plasma and dialysate sodium is important in the "fine tuning" of the intradialytic sodium mass balance (MB). The design of this study included part A: a retrospective analysis of predialysis plasma sodium concentrations extracted from a 6-year database in our HD population (147 prevalent white anuric patients); and part B: study of intradialytic sodium kinetics in 48 patients undergoing one 4-hour bicarbonate HD session. Direct potentiometry with an ion-selective electrode was used for sodium measurements. Study part A: the mean number of plasma sodium measurements per patient was 16.06 ± 14.03 over a mean follow-up of 3.55 ± 1.76 years. The mean of the averaged plasma sodium concentrations was 136.7 ± 2.1 mmol/L, with a low mean intraindividual coefficient of variation (1.39 ± 0.4). Study part B: mean predialysis and postdialysis plasma sodium concentrations were 135.8 ± 0.9 and 138.0 ± 0.9 mmol/L (p<0.001). Mean inlet dialyzer sodium concentration was 138.7 ± 1.1 mmol/L; the hourly diffusion concentration gradients showed a statistically significant transfer from dialysate to plasma (Wilks ? <0.0001). A statistically significant relationship was found between sodium MB and diffusion gradient (p<0.02), and between sodium MB and ultrafiltration volume (p<0.01). A relatively "fixed" and individual osmolar setpoint in HD patients was shown for the first time in a long-term follow-up. A dialysate sodium concentration of 140 mmol/L determined a dialysate to plasma sodium gradient.

  4. Synthesis of carbon-14-labeled sodium palmoxirate and its coenzyme A ester

    Energy Technology Data Exchange (ETDEWEB)

    Weaner, L.E.; Hoerr, D.C.

    1986-04-01

    Synthetic procedures for the preparation of carbon-14-labeled sodium palmoxirate (TDGA), labeled either in the carboxyl position or in the tetradecyl hydrocarbon chain, are described. In addition, the synthesis of the coenzyme A ester of TDGA-14C with a specific activity of 51 mCi/mmol is reported. The coenzyme A ester was prepared by formation of the acyl chloride with oxalyl chloride followed by reaction with coenzyme A (CoA) in a borate-buffered tetrahydrofuran solution. Purification methods and analytical and stability data are reported for the compounds.

  5. Surface modification, characterization and adsorptive properties of a coconut activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Lu Xincheng [Institute of Chemical Industry of Forest Products, CAF, National Engineering Lab. for Biomass Chemical Utilization, Key and Open Lab. of Forest Chemical Engineering, SFA, Key Lab. of Biomass Energy and Material, Jiangsu Province, Suojin wucun 16, Nanjing 210042 (China); Jiang Jianchun, E-mail: lhs_ac2011@yahoo.cn [Institute of Chemical Industry of Forest Products, CAF, National Engineering Lab. for Biomass Chemical Utilization, Key and Open Lab. of Forest Chemical Engineering, SFA, Key Lab. of Biomass Energy and Material, Jiangsu Province, Suojin wucun 16, Nanjing 210042 (China); Sun Kang; Xie Xinping; Hu Yiming [Institute of Chemical Industry of Forest Products, CAF, National Engineering Lab. for Biomass Chemical Utilization, Key and Open Lab. of Forest Chemical Engineering, SFA, Key Lab. of Biomass Energy and Material, Jiangsu Province, Suojin wucun 16, Nanjing 210042 (China)

    2012-08-01

    A coconut activated carbon was modified using chemical methods. Different concentration of nitric acid oxidation of the conventional sample produced samples with weakly acidic functional groups. The oxidized samples were characterized by scanning electron micrograph, nitrogen absorption-desorption, Fourier transform infra red spectroscopy, Bothem method, pH titration, adsorption capacity of sodium and formaldehyde, and the adsorption mechanism of activated carbons was investigated. The results showed that BET surface area and pore volume of activated carbons were decreased after oxidization process, while acidic functional groups were increased. The surface morphology of oxidized carbons looked clean and eroded which was caused by oxidization of nitric acid. The oxidized carbons showed high adsorption capacity of sodium and formaldehyde, and chemical properties of activated carbon played an important role in adsorption of metal ions and organic pollutants.

  6. Optimisation of entrapped activated carbon conditions to remove coloured compounds from winery wastewaters.

    Science.gov (United States)

    Devesa-Rey, R; Bustos, G; Cruz, J M; Moldes, A B

    2011-06-01

    The objective of this work was to study the entrapped conditions of activated carbon in calcium-alginate beads for the clarification of winery wastewaters. An incomplete 3(3) factorial design was carried out to study the efficiency of activated carbon (0.5-2%); sodium alginate (1-5%); and calcium chloride (0.050-0.900 M), on the following dependent variables: colour reduction at 280, 465, 530 and 665 nm. The activated carbon and calcium chloride were the most influential variables in the colour reduction. Nearly 100% colour reductions were found for the wavelengths assayed when employing 2% of activated carbon, 5% of sodium alginate and intermediate concentrations of calcium chloride (0.475 M). Instead, other conditions like, 2% of activated carbon, 4% of sodium alginate and 0.580 M of calcium chloride can also give absorbance reductions close to 100%. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Carbon isotopes and concentrations in mid-oceanic ridge basalts

    International Nuclear Information System (INIS)

    Pineau, F.; Javoy, M.

    1983-01-01

    In order to estimate carbon fluxes at mid-ocean ridges and carbon isotopic compositions in the convective mantle, we have studied carbon concentrations and isotopic compositions in tholeiitic glasses from the FAMOUS zone (Mid-Atlantic Ridge at 36 0 N) and East Pacific Rise from 21 0 N (RITA zone) to 20 0 S. These samples correspond essentially to the whole spectrum of spreading rates (2-16 cm/yr). The contain: -CO 2 vesicles in various quantities (3-220 ppm C) with delta 13 C between -4 and -9per mille relative to PDB, in the range of carbonatites and diamonds. - Carbonate carbon (3-100 ppm C) with delta 13 C between -2.6 and -20.0per mille relative to PDB. - Dissolved carbon at a concentration of 170+-10 ppm under 250 bar pressure with delta 13 C from -9 to -21per mille relative to PDB. This dissolved carbon, not contained in large CO 2 vesicles, corresponds to a variety of chemical forms among which part of the above carbonates, microscopic CO 2 bubbles and graphite. The lightest portions of this dissolved carbon are extracted at low temperatures (400-600 0 C) whereas the CO 2 from the vesicles is extracted near fusion temperature. These features can be explained by outgassing processes in two steps from the source region of the magma: (1) equilibrium outgassing before the second percolation threshold, where micron size bubbles are continuously reequilibrated with the magma; (2) distillation after the second percolation threshold when larger bubbles travel faster than magma concentrations to the surface. The second step may begin at different depths apparently related to the spreading rate, shallower for fast-spreading ridges than for slow-spreading ridges. (orig./WL)

  8. How Sodium Chloride Salt Inhibits the Formation of CO2 Gas Hydrates.

    Science.gov (United States)

    Holzammer, Christine; Finckenstein, Agnes; Will, Stefan; Braeuer, Andreas S

    2016-03-10

    We present an experimental Raman study on how the addition of sodium chloride to CO2-hydrate-forming systems inhibits the hydrate formation thermodynamically. For this purpose, the molar enthalpy of reaction and the molar entropy of reaction for the reaction of weakly hydrogen-bonded water molecules to strongly hydrogen bonded water molecules are determined for different salinities from the Raman spectrum of the water-stretching vibration. Simultaneously, the influence of the salinity on the solubility of CO2 in the liquid water-rich phase right before the start of hydrate formation is analyzed. The results demonstrate that various mechanisms contribute to the inhibition of gas hydrate formation. For the highest salt concentration of 20 wt % investigated, the temperature of gas hydrate formation is lowered by 12 K. For this concentration the molar enthalpy and entropy of reaction become smaller by 50 and 20%, respectively. Concurrently, the solubility of carbon dioxide is reduced by 70%. These results are compared with data in literature for systems of sodium chloride in water (without carbon dioxide).

  9. Glassy carbon electrode modified with multi-walled carbon nanotubes sensor for the quantification of antihistamine drug pheniramine in solubilized systems

    Directory of Open Access Journals (Sweden)

    Rajeev Jain

    2012-02-01

    Full Text Available A sensitive electroanalytical method for quantification of pheniramine in pharmaceutical formulation has been investigated on the basis of the enhanced electrochemical response at glassy carbon electrode modified with multi-walled carbon nanotubes in the presence of sodium lauryl sulfate. The experimental results suggest that the pheniramine in anionic surfactant solution exhibits electrocatalytic effect resulting in a marked enhancement of the peak current response. Peak current response is linearly dependent on the concentration of pheniramine in the range 200–1500 μg/mL with correlation coefficient 0.9987. The limit of detection is 58.31 μg/mL. The modified electrode shows good sensitivity and repeatability. Keywords: Pheniramine, Sodium lauryl sulfate (SLS, Glassy carbon electrode modified with multi-walled carbon nanotubes (GCE-MWCNTs, Solubilized systems, Voltammetric quantification

  10. Radiochemical measurement of mass transport in sodium

    International Nuclear Information System (INIS)

    Cooper, M.H.; Chiang, S.H.

    1976-01-01

    Mass transport processes in the sodium coolant of Liquid Metal Fast Breeder Reactors (LMFBRs) are significant in determining rates of corrosion and deposition of radioactive nuclides from the fuel cladding, deposition and cold trapping of fission products from defect or failed fuel, carbon and nitrogen redistribution in the containment materials, and removal of impurities by cold trapping or hot trapping. Mass transport between rotating, concentric cylinders in molten sodium has been investigated using a unique radiochemical method. Long-lived (33 year) cesium-137, dissolved in the sodium, decays radioactively emitting a beta to barium-137m, which decays with a short half-life (2.6 minutes) emitting a gamma. Cesium is weakly adsorbed and remains in solution, while the barium is strongly adsorbed on the stainless steel surfaces. Hence, by measuring the barium-137m activity on movable stainless steel surfaces, one can calculate the mass transport to that surface. Mass transfer coefficients in sodium measured by this method are in agreement with published heat transfer correlations when the effect of the volumetric mass source is taken into account. Hence, heat transfer correlations can be confidently utilized by analogy in estimating mass transfer in liquid-metal systems

  11. Adsorption of carbon-14 on mortar

    International Nuclear Information System (INIS)

    Matsumoto, Junko; Banba, Tsunetaka; Muraoka, Susumu

    1995-01-01

    The sorption experiments of carbon-14 on the mortar grain (grain size: 0.50--1.0 mm) focused on the chemical form of the carbon-14 were carried out by the batch method. Three kinds of carbon-14 chemical form were used for the experiments: sodium carbonate (Na 2 14 CO 3 ) as the inorganic radiocarbon, and sodium acetate (CH 3 14 COONa) and acetaldehyde ( 14 CH 3 14 CHO) as the organic radiocarbons. 0.30 gram samples of mortar were soaked in the solution with carbon-14 at 15 C for periods of up to 160 days. At the end of each run, carbon-14 concentrations in the supernatants were determined before and after centrifugation (3,500 rpm., 1 hr). In the mortar-sodium carbonate system, the retention process of carbon-14 related to reaction on the surface of the mortar was speculated as follows. First, 3CaO-SiO 2 and 2CaO-SiO 2 of the mortar components contact with water and produce Ca(OH) 2 . Ca(OH) 2 produces Ca 2+ and OH - in the solution. Then, calcite forms from Ca 2+ and CO 3 2- in the solution. Thus, the sorption ratio of carbon-14 onto mortar will be high until mortar has been completely carbonated because Ca 2+ is rich in the mortar and the solubility of calcite is low. In the mortar-organic carbon system, the soluble organic carbon-14 is hardly sorbed on the surface of the mortar. Therefore, the cementitious materials may not inhibit the release of organic radiocarbons from the low-level radioactive wastes, contrary to the case of inorganic radiocarbon

  12. The Effect of DNA and Sodium Cholate Dispersed Single-Walled Carbon Nano tubes on the Green Algae Chlamydomonas reinhardtii

    International Nuclear Information System (INIS)

    Williams, R.M.; Cox, Z.; Dolash, B.D.; Sooter, L.J.; Williams, R.M.; Taylor, H.K.; Thomas, J.

    2014-01-01

    Increasing use of single-walled carbon nano tubes (SWCNTs) will lead to their increased release into the environment. Previous work has shown negative effects of SWCNT on growth and survival of model organisms. The aim of the current study was to determine the effect of SWCNT well-dispersed by either DNA or sodium cholate (SC) on the unicellular green algae Chlamydomonas reinhardtii in stagnant water conditions. Growth measurements were taken up to ten days for algae treated with varied levels of DNA:SWCNT or SC:SWCNT or controls, and chlorophyll content after 10 days was determined. Results show no effect on either growth or chlorophyll content of algae at any concentration or duration. This is in contradiction to prior work showing toxicity of SWCNT to environmental model organisms.

  13. Extraction of transplutonium elements from carbonate solutions by alkylpyrocatechol

    International Nuclear Information System (INIS)

    Karalova, Z.K.; Myasoedov, B.F.; Rodionova, L.M.; Kuznetsova, V.S.

    1983-01-01

    Extraction of americium, berkelium as well as Ce, Eu, Th, U, Zr, Cs, Fe with solution of 4(α, α-dioctylethyl)pyrocatechol (DOP) in toluene from carbonate solutions to determine conditions of their separation has been studied. It is established that americium extraction is quite sensitive to the changes of potassium carbonate concentration. The maximum extraction of americium (R >90%) is observed in the case of 0.1-0.5 mol/l of K 2 CO 3 solutions and the minimum one (R=2.5%) - in the case of 8 mol/l K 2 CO 3 . Americium extraction increases sharply when sodium hydroxide is introduced in carbonate solutions. It is shown that varying sodium hydroxide concentration it is possible to achieve qualitative extraction of americium even from saturated solution of potassium carbonate. Reextraction of TPE is easily realized with 3 mol/l HCl solution. The system K 2 CO 3 (KOH)-DOP proved to be perspective for Am separation from Bk, Ce, Cs, actinoid elements as well as from Fe

  14. Study of Activated Carbons by Pyrolysis of Mangifera Indica Seed (Mango in Presence of Sodium and Potassium Hydroxide

    Directory of Open Access Journals (Sweden)

    J. C. Moreno-Piraján

    2012-01-01

    Full Text Available Activated carbons (ACs were prepared by pyrolysis of seeds mango in presence of sodium and potassium hydroxide (chemical activities. Seeds mango from Colombian Mango cultives were impregnated with aqueous solutions of NaOH and KOH following a variant of the incipient wetness method. Different concentrations were used to produce impregnation ratios of 3:1 (weight terms. Activation was carried out under argon flow by heating to 823 K with 1 h soaking time. The porous texture of the obtained ACs was characterized by physical adsorptions of N2 at 77 K and CO2 at 273 K. The impregnation ration and hydroxide type had a strong influence on the pore structure of these ACs, which could be easily controlled by simply varying the proportion of the hydroxides used in the activation. Thus, the development of porosity for precursors with low structural order (high reactivity is better with NaOH than KOH, whereas the opposite is observed for the highly ordered ones. Variable adsorption capacities and porosity distributions can be achieved depending on the activating agent selected. In general, KOH produces activated carbons with narrower micropore distributions than those prepared by NaOH.

  15. The carbon-nitrogen balance of the nodule and its regulation under elevated carbon dioxide concentration.

    Science.gov (United States)

    Libault, Marc

    2014-01-01

    Legumes have developed a unique way to interact with bacteria: in addition to preventing infection from pathogenic bacteria like any other plant, legumes also developed a mutualistic symbiotic relationship with one gender of soil bacteria: rhizobium. This interaction leads to the development of a new root organ, the nodule, where the differentiated bacteria fix for the plant the atmospheric dinitrogen (atmN2). In exchange, the symbiont will benefit from a permanent source of carbon compounds, products of the photosynthesis. The substantial amounts of fixed carbon dioxide dedicated to the symbiont imposed to the plant a tight regulation of the nodulation process to balance carbon and nitrogen incomes and outcomes. Climate change including the increase of the concentration of the atmospheric carbon dioxide is going to modify the rates of plant photosynthesis, the balance between nitrogen and carbon, and, as a consequence, the regulatory mechanisms of the nodulation process. This review focuses on the regulatory mechanisms controlling carbon/nitrogen balances in the context of legume nodulation and discusses how the change in atmospheric carbon dioxide concentration could affect nodulation efficiency.

  16. Development of a Rapid, Nondestructive Method to Measure Aqueous Carbonate in High Salinity Brines Using Raman Spectroscopy

    Science.gov (United States)

    McGraw, L.; Phillips-Lander, C. M.; Elwood Madden, A. S.; Parnell, S.; Elwood Madden, M.

    2015-12-01

    Traditional methods of quantitative analysis are often ill-suited to determining the bulk chemistry of high salinity brines due to their corrosive and clogging properties. Such methods are also often difficult to apply remotely in planetary environments. However, Raman spectroscopy can be used remotely without physical contact with the fluid and is not affected by many ionic brines. Developing methods to study aqueous carbonates is vital to future study of brines on Mars and other planetary bodies, as they can reveal important information about modern and ancient near-surface aqueous processes. Both sodium carbonate standards and unknown samples from carbonate mineral dissolution experiments in high salinity brines were analyzed using a 532 nm laser coupled to an inVia Renishaw spectrometer to collect carbonate spectra from near-saturated sodium chloride and sodium sulfate brines. A calibration curve was determined by collecting spectra from solutions of known carbonate concentrations mixed with a pH 13 buffer and a near-saturated NaCl or Na2SO4 brine matrix. The spectra were processed and curve fitted to determine the height ratio of the carbonate peak at 1066 cm-1 to the 1640 cm-1 water peak. The calibration curve determined using the standards was then applied to the experimental data after accounting for dilutions. Concentrations determined based on Raman spectra were compared against traditional acid titration measurements. We found that the two techniques vary by less than one order of magnitude. Further work is ongoing to verify the method and apply similar techniques to measure aqueous carbonate concentrations in other high salinity brines.Traditional methods of quantitative analysis are often ill-suited to determining the bulk chemistry of high salinity brines due to their corrosive and clogging properties. Such methods are also often difficult to apply remotely in planetary environments. However, Raman spectroscopy can be used remotely without physical

  17. The radiation chemistry of aqueous sodium terephthalate solutions

    International Nuclear Information System (INIS)

    Matthews, R.W.

    1980-04-01

    The radiation chemistry of cobalt-60 gamma-irradiated aqueous sodium terephthalate solutions has been studied. In aerated 4 x 10 -4 M sodium hydroxide solutions, the main products are hydroxyterephthalate (HTA) (G = 0.99 +- 0.01), carbonate (G = 1.31 +- 0.08), and peroxides (G = 2.84 +- 0.04). The HTA and carbonate species are both formed as a result of hydroxyl radical attack and account for approximately 90 per cent of hydroxyl radical reactions. Oxygen needs to be present for efficient conversion of the terephthalate-OH radical adduct to HTA and oxygenation increases G(HTA) above the aerated solution value. G(HTA) is unaffected by changes in terephthalate concentration between 1 x 10 -4 M and 1 x 10 -2 M in sodium hydroxide solutions at pH 10. Decreasing the solution pH does however affect G(HTA). In phosphate buffered solutions pH 6.85, G(HTA) is 0.93 +- 0.01 and lower values are obtained with further decrease in solution pH. The lowering of the G(HTA) value is attributed to recombination reactions between the terephthalate-OH radical products and reducing radical products. Experimental evidence supporting the recombination postulate was obtained from the measurement of a parallel decrease in the peroxide yield and the observation of a dose rate effect on G(HTA). Competition kinetic studies with the added solutes carbonate and bicarbonate gave the rate ratios k (OH + TA 2- ) : k(OH + CO 3 2- ) : k(OH + HCO 3 - ) = 1 : 0.105 : 0.0036

  18. Comparison of sodium carbonate-oxygen and sodium hydroxide-oxygen pretreatments on the chemical composition and enzymatic saccharification of wheat straw.

    Science.gov (United States)

    Geng, Wenhui; Huang, Ting; Jin, Yongcan; Song, Junlong; Chang, Hou-Min; Jameel, Hasan

    2014-06-01

    Pretreatment of wheat straw with a combination of sodium carbonate (Na2CO3) or sodium hydroxide (NaOH) with oxygen (O2) 0.5MPa was evaluated for its delignification ability at relatively low temperature 110°C and for its effect on enzymatic hydrolysis efficiency. In the pretreatment, the increase of alkali charge (as Na2O) up to 12% for Na2CO3 and 6% for NaOH, respectively, resulted in enhancement of lignin removal, but did not significantly degrade cellulose and hemicellulose. When the pretreated solid was hydrolyzed with a mixture of cellulases and hemicellulases, the sugar yield increased rapidly with the lignin removal during the pretreatment. A total sugar yield based on dry matter of raw material, 63.8% for Na2CO3-O2 and 71.9% for NaOH-O2 was achieved under a cellulase loading of 20FPU/g-cellulose. The delignification efficiency and total sugar yield from enzymatic hydrolysis were comparable to the previously reported results at much higher temperature without oxygen. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Riverine dissolved carbon concentration and yield in subtropical catchments, Taiwan

    Science.gov (United States)

    Chen, Pei-Hao; Shih, Yu-ting; Huang, -Chuan, Jr.

    2017-04-01

    Dissolved carbon is not highly correlated to carbon cycle, but also a critical water quality indicator and affected by interaction of terrestrial and aquatic environment at catchment scale. However, the rates and extent of the dissolved carbon export are still poorly understood and scarcely quantified especially for typhoon events. In this study, regular and events' data of riverine dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) were monitored to estimate the export. Meanwhile, the hydrological model and mixing model were used for determination of DOC and DIC flow pathways at 3 sites of Tsengwen reservoir in southern Taiwan in 2014-2015. Results showed that the mean DOC concentration was 1.5 - 2.2 mg l-1 (flow weighted) without seasonal variation. The average DOC yield was 3.1 ton-C km-2 yr-1. On the other hand, DIC concentration ranged from 15 to 25.8 mg l-1, but DIC concentration in dry season was higher than wet season. Mean annual DIC yield was 51 ton-C km-2 yr-1. The export-ratio of DOC:DIC was 1:16.5, which was extremely lower than that of worldwide large rivers (DOC:DIC=1:4.5 in average) and other mountainous rivers (DOC:DIC=1:4.6 in average). Both DOC and DIC concentration showed the dramatically discrepant change in typhoon events. The DOC concentration increased to 4-8 folds rapidly before the flood peak. However, DIC concentration was diluted to one third with discharge simultaneously and returned slowly to base concentration in more than a week. According to the hydrological model, events contributed 14.6% of the annual discharge and 21.9% and 11.1% of DOC and DIC annual flux, respectively. Furthermore, 68.9% of events' discharge derived from surface runoff which carried out 91.3% of DOC flux and 51.1% of DIC flux. It implied that increases of surface runoff transported DOC form near soil surface, but diluted DIC concentration likely implied the contribution of groundwater. Our study characterized the specialty of dissolved carbon

  20. Handheld Device Adapted to Smartphone Cameras for the Measurement of Sodium Ion Concentrations at Saliva-Relevant Levels via Fluorescence

    Directory of Open Access Journals (Sweden)

    Michelle Lipowicz

    2015-06-01

    Full Text Available The use of saliva sampling as a minimally-invasive means for drug testing and monitoring physiology is a subject of great interest to researchers and clinicians. This study describes a new optical method based on non-axially symmetric focusing of light using an oblate spheroid sample chamber. The device is simple, lightweight, low cost and is easily attached to several different brands/models of smartphones (Apple, Samsung, HTC and Nokia for the measurement of sodium ion levels at physiologically-relevant saliva concentrations. The sample and fluorescent reagent solutions are placed in a specially-designed, lightweight device that excludes ambient light and concentrates 470-nm excitation light, from a low-power photodiode, within the sample through non-axially-symmetric refraction. The study found that smartphone cameras and post-image processing quantitated sodium ion concentration in water over the range of 0.5–10 mM, yielding best-fit regressions of the data that agree well with a data regression of microplate luminometer results. The data suggest that fluorescence can be used for the measurement of salivary sodium ion concentrations in low-resource or point-of-care settings. With further fluorescent assay testing, the device may find application in a variety of enzymatic or chemical assays.

  1. Chemistry and Mechanism of Interaction Between Molybdenite Concentrate and Sodium Chloride When Heated in the Presence of Oxygen

    Science.gov (United States)

    Aleksandrov, P. V.; Medvedev, A. S.; Imideev, V. A.; Moskovskikh, D. O.

    2017-04-01

    Roasting of molybdenum concentrates with sodium chloride has high potential and can be an alternative to oxidizing roasting and autoclave leaching; however, the chemistry and mechanism are poorly known. The chemical mechanism of the roasting process between molybdenite concentrate and sodium chloride in the presence of atmospheric oxygen is proposed. It is demonstrated that the process occurs through molybdenite oxidation, up to molybdenum trioxide, with subsequent formation of sodium polymolybdates and molybdenum dioxydichloride from molybdenum trioxide. It is found that the formation of water-soluble sodium polymolybdates from molybdenum trioxide stops over time due to passivation of sodium chloride surface by polymolybdates. It is proved experimentally that preliminary grinding of the mixture in a furnace charge leads to an increase in the polymolybdate fraction of the roasting products, which constitutes approximately 65 pct of molybdenum initially in the roasted mixture against 20 to 22 pct in a nonground mixture (or 75 to 77 pct against 30 to 33 pct of molybdenum in calcine). For the first time, the presence of the Na2S2O7 phase in the calcine was confirmed experimentally. The suggested mechanism gives possible explanations for the sharp increase of MoO2Cl2 formation within the temperature range of 673 K to 723 K (400 °C to 450 °C) that is based on the catalytic reaction of molybdenum dioxydichloride from the Na2S2O7 liquid phase as it runs in a melt.

  2. High-resolution carbon dioxide concentration record 650,000-800,000 years before present

    Energy Technology Data Exchange (ETDEWEB)

    Luthi, D; Bereiter, B; Blunier, T; Siegenthaler, U; Kawamura, K; Stocker, T F [Climate and Environm. Physics, Physics Inst., Univ. Bern, CH-3012 Bern, (Switzerland); Luthi, D; Bereiter, B; Blunier, T; Siegenthaler, U; Kawamura, K; Stocker, T F [Oeschger Centre for Climate Change Research, Univ. Bern, CH-3012 Bern, (Switzerland); Le Floch, M; Barnola, J M; Raynaud, D [LGGE, CNRS-Univ. Grenoble 1, F-38402 Saint Martin d' Heres, (France); Jouzel, J [Inst. Pierre Simon Laplace, LSCE, CEA-CNRS-Universite Versailles-Saint Quentin, CEA Saclay, F-91191 Gif sur Yvette (France); Fischer, H [Alfred Wegener Inst. for Polar and Maine Research, D-27568 Bremerhaven, (Germany)

    2008-07-01

    Changes in past atmospheric carbon dioxide concentrations can be determined by measuring the composition of air trapped in ice cores from Antarctica. So far, the Antarctic Vostok and EPICA Dome C ice cores have provided a composite record of atmospheric carbon dioxide levels over the past 650,000 years. Here we present results of the lowest 200 m of the Dome C ice core, extending the record of atmospheric carbon dioxide concentration by two complete glacial cycles to 800,000 yr before present. From previously published data and the present work, we find that atmospheric carbon dioxide is strongly correlated with Antarctic temperature throughout eight glacial cycles but with significantly lower concentrations between 650,000 and 750,000 yr before present. Carbon dioxide levels are below 180 parts per million by volume (p.p.m.v.) for a period of 3,000 yr during Marine Isotope Stage 16, possibly reflecting more pronounced oceanic carbon storage. We report the lowest carbon dioxide concentration measured in an ice core, which extends the pre-industrial range of carbon dioxide concentrations during the late Quaternary by about 10 p.p.m.v. to 172-300 p.p.m.v. (authors)

  3. Solubility of NaNd(CO3)2.6H2O(c) in concentrated Na2CO3 and NaHCO3 solutions

    International Nuclear Information System (INIS)

    Rao, L.; Rai, D.; Felmy, A.R.; Fulton, R.W.; Novak, C.F.

    1996-01-01

    NaNd(CO 3 ) 2 x 6 H 2 O(c) was identified to be the final equilibrium solid phase in suspensions containing concentrated sodium carbonate (0.1 to 2.0 M) and sodium bicarbonate (0.1 to 1.0 M), with either NaNd(CO 3 ) 2 x 6 H 2 O(c) or Nd 2 (CO 3 ) 3 x xH 2 O(s) as initial solids. A thermodynamic model, based on Pitzer's specific into-interaction approach, was developed to interpret the solubility of NaNd(CO 3 ) 2 x 6 H 2 O(c) as functions of sodium carbonate and sodium bicarbonate concentrations. In this model, the solubility data of NaNd(CO 3 ) 2 x 6 H 2 O(c) were explained by assuming the formation of NdCO 3 + , Nd(CO 3 ) 2 - and Nd(CO 3 ) 3 3- species and invoking the specific ion interactions between Na + and Nd(CO 3 ) 3 3- . Ion interaction parameters for Na + -Nd(CO 3 ) 3 3- were developed to fit the solubility data. Based on the model calculations, Nd(CO 3 ) 3 3- was the predominant aqueous neodymium species in 0.1 to 2 M sodium carbonate and 0.1 to 1 M sodium bicarbonate solutions. The logarithm of the NaNd(CO 3 ) 2 x 6 H 2 O solubility product (NaNd(CO 3 ) 2 x 6 H 2 O(c)=Na + +Nd 3+ +2 CO 3 2- +6 H 2 O) was calculated to be -21.39. This model also provided satisfactory interpretation of the solubility data of the analogous Am(III) system in less concentrated carbonate and bicarbonate solutions. (orig.)

  4. Kinetic Effect on the Freezing of Ammonium-Sodium-Carbonate-Chloride Brines and Implications for Origin of Ceres' Bright Spots

    Science.gov (United States)

    Hodyss, R. P.; Thomas, E. C.; Vu, T. H.; Johnson, P. V.; Choukroun, M.

    2017-12-01

    Subsurface brines on Ceres containing natrite (Na2CO3) and smaller amounts of NH4Cl or NH4HCO3 have been proposed to reach the dwarf planet's surface from an internal reservoir, where the brines freeze and result in bright spots across Ceres. Kinetically frozen solutions containing the likely constituents of Ceres' subsurface brines (ammonium, sodium, carbonate, and chloride ions) were studied via infrared and micro-Raman spectroscopy, where the flash-frozen mixtures were found to preferentially form ammonium chloride and ammonium bicarbonate, even in sodium-dominated solutions. Additionally, sodium chloride only formed when sodium or chloride (or both) were present in excess in the brine solutions. Raman spectroscopy was further employed to analyze the effect of vacuum exposure on these frozen brines over longer periods of time to simulate the surface conditions of Ceres.

  5. Manipulating Adsorption-Insertion Mechanisms in Nanostructured Carbon Materials for High-Efficiency Sodium Ion Storage

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Shen [College of Chemistry and Molecular Sciences, Hubei Key Laboratory of Electrochemical Power Sources, Wuhan University, Wuhan 430072 China; Xiao, Lifen [College of Chemistry, Central China Normal University, Wuhan 430079 China; Pacific Northwest National Laboratory, Richland WA 99352 USA; Sushko, Maria L. [Pacific Northwest National Laboratory, Richland WA 99352 USA; Han, Kee Sung [Pacific Northwest National Laboratory, Richland WA 99352 USA; Shao, Yuyan [Pacific Northwest National Laboratory, Richland WA 99352 USA; Yan, Mengyu [State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070 China; Liang, Xinmiao [State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Science, Wuhan 430071 China; Mai, Liqiang [State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070 China; Feng, Jiwen [State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Science, Wuhan 430071 China; Cao, Yuliang [College of Chemistry and Molecular Sciences, Hubei Key Laboratory of Electrochemical Power Sources, Wuhan University, Wuhan 430072 China; Ai, Xinping [College of Chemistry and Molecular Sciences, Hubei Key Laboratory of Electrochemical Power Sources, Wuhan University, Wuhan 430072 China; Yang, Hanxi [College of Chemistry and Molecular Sciences, Hubei Key Laboratory of Electrochemical Power Sources, Wuhan University, Wuhan 430072 China; Liu, Jun [Pacific Northwest National Laboratory, Richland WA 99352 USA

    2017-05-12

    Hard carbon is one of the most promising anode materials for sodium-ion batteries, but the low coulombic efficiency is still a key barrier. In this paper we synthesized a series of nanostructured hard carbon materials with controlled architectures. Using a combination of in-situ XRD mapping, ex-situ NMR, EPR, electrochemical techniques and simulations, an “adsorption-intercalation” (A-I) mechanism is established for Na ion storage. During the initial stages of Na insertion, Na ions adsorb on the defect sites of hard carbon with a wide adsorption energy distribution, producing a sloping voltage profile. In the second stage, Na ions intercalate into graphitic layers with suitable spacing to form NaCx compounds similar to the Li ion intercalation process in graphite, producing a flat low voltage plateau. The cation intercalation with a flat voltage plateau should be enhanced and the sloping region should be avoided. Guided by this knowledge, non-porous hard carbon material has been developed which has achieved high reversible capacity and coulombic efficiency to fulfill practical application.

  6. Processing of Madagascar's concentrates; Traitement des concentres de Madagascar

    Energy Technology Data Exchange (ETDEWEB)

    Mouret, P; Madinier, A

    1949-06-01

    This report describes the equipment (tanks, filters..) of the ore processing workshop of Le Bouchet used for the processing of the uranium ore from Madagascar (autunite). Then it describes the processing scheme: treatment with sodium carbonate, de-complexing of uranyl carbonate with soda, filtering, washing, drying and calcination of sodium uranate. The volume of reagents used, the production rate and the purity of the uranate obtained are given in conclusion. (J.S.)

  7. Molecular dynamics simulation of siderite-hematite-quartz flotation with sodium oleate

    Science.gov (United States)

    Li, Lixia; Hao, Haiqing; Yuan, Zhitao; Liu, Jiongtian

    2017-10-01

    Models of sodium oleate adsorption on siderite, hematite and quartz were investigated by molecular dynamic simulation, respectively. Surface energy was calculated to confirm the cleavage plan of hematite and quartz. Both natural cleavage plane of siderite and calculated plane were used to investigate the flotation of the three minerals. Based on the molecular simulation in solution with water as medium, adsorption quantity and interaction capability of oleate ions on the three minerals indicated that siderite could be collected efficiently by sodium oleate at neutral pH. Results of flotation experiments were further demonstrated by analysis of relative concentration of carbon atoms and oxygen atoms.

  8. Application of the radioisotope process when studying the decarbonization of low-alloy multicomponent steels in sodium

    International Nuclear Information System (INIS)

    Pavlinov, L.V.; Evstratov, V.D.

    1982-06-01

    By means of the radioisotope process and the method of a planning matrix for factor experiments quantitative values have been found for the influence of alloys of chromium molybdenum, niobium, vanadium, titanium on the decarbonization of low alloy pearlitic steels in sodium at temperatures of 500 to 800 0 C. It has been proved that of all alloys with a concentration of 1 to 3% Cr, 1 to 2% Mo, 0 to 1% Nb, 0 to 0.25% V, and 0 to 0.25% Ti, which had been studied, the alloys of iron with 1-3% Cr and 1% Mo showed the greatest tendency for decarbonization in sodium where the carbon concentration decreases from 0.01 to 0.02% at the surface. An increase of the concentration of molybdenum and especially of niobium and titanium leads to a decrease of the decarbonization tendency of steel because the surface concentration of carbon remains at the level of 0.08 to 0.09% in alloys which contain up to 1% niobium and in complex alloy steels with up to 1% niobium, 0.25% vanadium, and 0.25% titanium. (orig.) [de

  9. Evaluation of cardiovascular toxicity of carbon nanotubes functionalized with sodium hyaluronate in oral regenerative medicine

    Energy Technology Data Exchange (ETDEWEB)

    Joviano-Santos, J.V.; Sá, M.A.; De Maria, M.L.A.; Almeida, T.C.S. [Departamento de Morfologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Geraldo, V.; Oliveira, S.; Ladeira, L.O. [Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Ferreira, A.J. [Departamento de Morfologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil)

    2014-05-23

    It has been demonstrated that carbon nanotubes (CNTs) associated with sodium hyaluronate (HY-CNTs) accelerate bone repair in the tooth sockets of rats. Before clinical application of HY-CNTs, it is important to assess their biocompatibility. Moreover, cardiac toxicity may be caused by the translocation of these particles to the blood stream. The aim of this study was to evaluate possible changes in cardiovascular function in male Wistar rats whose tooth sockets were treated with either CNTs or HY-CNTs (100 μg/mL, 0.1 mL). Blood pressure and heart rate were monitored in conscious rats 7 days after treatment. Cardiac function was evaluated using the Langendorff perfusion technique. The data showed no changes in blood pressure or heart rate in rats treated with either CNTs or HY-CNTs, and no significant changes in cardiac function were found in any of the groups. To confirm these findings, experiments were conducted in rats injected intraperitoneally with a high concentration of either CNTs or HY-CNTs (0.75 mg/kg). The same parameters were analyzed and similar results were observed. The results obtained 7 days following injection indicate that the administration of low concentrations of CNTs or HY-CNTs directly into tooth sockets did not cause any significant change in cardiovascular function in the rats. The present findings support the possibility of using these biocomposites in humans.

  10. Final report on the safety assessment of potassium silicate, sodium metasilicate, and sodium silicate.

    Science.gov (United States)

    Elmore, Amy R

    2005-01-01

    Potassium Silicate, Sodium Metasilicate, and Sodium Silicate combine metal cations with silica to form inorganic salts used as corrosion inhibitors in cosmetics. Sodium Metasilicate also functions as a chelating agent and Sodium Silicate as a buffering and pH adjuster. Sodium Metasilicate is currently used in 168 formulations at concentrations ranging from 13% to 18%. Sodium Silicate is currently used in 24 formulations at concentrations ranging from 0.3% to 55%. Potassium Silicate and Sodium Silicate have been reported as being used in industrial cleaners and detergents. Sodium Metasilicate is a GRAS (generally regarded as safe) food ingredient. Aqueous solutions of Sodium Silicate species are a part of a chemical continuum of silicates based on an equilibrium of alkali, water, and silica. pH determines the solubility of silica and, together with concentration, determines the degree of polymerization. Sodium Silicate administered orally is readily absorbed from the alimentary canal and excreted in the urine. The toxicity of these silicates has been related to the molar ratio of SiO2/Na2O and the concentration being used. The Sodium Metasilicate acute oral LD50 ranged from 847 mg/kg in male rats to 1349.3 mg/kg in female rats and from 770 mg/kg in female mice to 820 mg/kg in male mice. Gross lesions of variable severity were found in the oral cavity, pharynx, esophagus, stomach, larynx, lungs, and kidneys of dogs receiving 0.25 g/kg or more of a commercial detergent containing Sodium Metasilicate; similar lesions were also seen in pigs administered the same detergent and dose. Male rats orally administered 464 mg/kg of a 20% solution containing either 2.0 or 2.4 to 1.0 ratio of sodium oxide showed no signs of toxicity, whereas doses of 1000 and 2150 mg/kg produced gasping, dypsnea, and acute depression. Dogs fed 2.4 g/kg/day of Sodium Silicate for 4 weeks had gross renal lesions but no impairment of renal function. Dermal irritation of Potassium Silicate, Sodium

  11. Classroom Carbon Dioxide Concentration, School Attendance, and Educational Attainment

    Science.gov (United States)

    Gaihre, Santosh; Semple, Sean; Miller, Janice; Fielding, Shona; Turner, Steve

    2014-01-01

    Background: We tested the hypothesis that classroom carbon dioxide (CO[subscript 2]) concentration is inversely related to child school attendance and educational attainment. Methods: Concentrations of CO[subscript 2] were measured over a 3-5?day period in 60 naturally ventilated classrooms of primary school children in Scotland. Concentrations of…

  12. Sodium pool fire analysis of sodium-cooled fast reactor by calculation

    International Nuclear Information System (INIS)

    Yu Hong; Xu Mi; Jin Degui

    2002-01-01

    Theoretical models were established according to the characteristic of sodium pool fire, and the SPOOL code was created independently. Some transient processes in sodium pool fire were modeled, including chemical reaction of sodium and oxygen; sodium combustion heat transfer modes in several kids of media; production, deposition and discharge of sodium aerosol; mass and energy exchange between different media in different ventilating conditions. The important characteristic parameters were calculated, such as pressure and temperature of gas, temperature of building materials, mass concentration of sodium aerosol, and so on. The SPOOL code, which provided available safety analysis tool for sodium pool fire accidents in sodium-cooled fast reactor, was well demonstrated with experimental data

  13. Identification of impurities in sodium and its purification

    International Nuclear Information System (INIS)

    Subbotin, B.I.; Voltchkov, L.G.; Kozlov, F.A.; Zagorulko, Yu.I.; Kuznetsov, E.K.

    1976-01-01

    The paper presents some investigation results on sodium technology. In particular, a description is given of a calculation method for evaluation of sodium-cover gas-impurities equilibrium compositions as well as experimental results on development of methods for sodium sampling, equipment for non-metallic impurities (oxygen, hydrogen, carbon) constant control in sodium. The investigation results on sodium purification with cold traps are presented

  14. Comparative toxicity of sodium carbonate peroxyhydrate to freshwater organisms.

    Science.gov (United States)

    Geer, Tyler D; Kinley, Ciera M; Iwinski, Kyla J; Calomeni, Alyssa J; Rodgers, John H

    2016-10-01

    Sodium carbonate peroxyhydrate (SCP) is a granular algaecide containing H2O2 as an active ingredient to control growth of noxious algae. Measurements of sensitivities of target and non-target species to hydrogen peroxide are necessary for water resource managers to make informed decisions and minimize risks for non-target species when treating noxious algae. The objective of this study was to measure and compare responses among a target noxious alga (cyanobacterium Microcystis aeruginosa) and non-target organisms including a eukaryotic alga (chlorophyte Pseudokirchneriella subcapitata), microcrustacean (Ceriodaphnia dubia), benthic amphipod (Hyalella azteca), and fathead minnow (Pimephales promelas) to exposures of hydrogen peroxide as SCP. Hydrogen peroxide exposures were confirmed using the I3(-) method. SCP margins of safety for these organisms were compared with published toxicity data to provide context for other commonly used algaecides and herbicides (e.g. copper formulations, endothall, and diquat dibromide). Algal responses (cell density and chlorophyll a concentrations) and animal mortality were measured after 96h aqueous exposures to SCP in laboratory-formulated water to estimate EC50 and LC50 values, as well as potency slopes. Despite a shorter test duration, M. aeruginosa was more sensitive to hydrogen peroxide as SCP (96h EC50:0.9-1.0mgL(-)(1) H2O2) than the eukaryotic alga P. subcapitata (7-d EC50:5.2-9.2mgL(-1) H2O2), indicating potential for selective control of prokaryotic algae. For the three non-target animals evaluated, measured 96-h LC50 values ranged from 1.0 to 19.7mgL(-1) H2O2. C. dubia was the most sensitive species, and the least sensitive species was P. promelas, which is not likely to be affected by concentrations of hydrogen peroxide as SCP that would be used to control noxious algae (e.g. M. aeruginosa). Based on information from peer-reviewed literature, other algaecides could be similarly selective for cyanobacteria. Of the

  15. Visibility in sodium fume

    International Nuclear Information System (INIS)

    Hughes, G.W.; Anderson, N.R.

    1971-01-01

    The appearance of sodium fume of unknown concentration and the effects of short term exposure on unprotected workers is described. The molecular extinction coefficient of sodium fume is calculated from which light transmission data, and a rapid method for the estimation of the fume concentration is proposed. (author)

  16. Comparison of Prescribed and Measured Dialysate Sodium: A Quality Improvement Project.

    Science.gov (United States)

    Gul, Ambreen; Miskulin, Dana C; Paine, Susan S; Narsipur, Sriram S; Arbeit, Leonard A; Harford, Antonia M; Weiner, Daniel E; Schrader, Ronald; Horowitz, Bruce L; Zager, Philip G

    2016-03-01

    There is controversy regarding the optimal dialysate sodium concentration for hemodialysis patients. Dialysate sodium concentrations of 134 to 138 mEq/L may decrease interdialytic weight gain and improve hypertension control, whereas a higher dialysate sodium concentration may offer protection to patients with low serum sodium concentrations and hypotension. We conducted a quality improvement project to explore the hypothesis that prescribed and delivered dialysate sodium concentrations may differ significantly. Cross-sectional quality improvement project. 333 hemodialysis treatments in 4 facilities operated by Dialysis Clinic, Inc. Measure dialysate sodium to assess the relationships of prescribed and measured dialysate sodium concentrations. Magnitude of differences between prescribed and measured dialysate sodium concentrations. Dialysate sodium measured pre- and late dialysis. The least square mean of the difference between prescribed minus measured dialysate sodium concentration was -2.48 (95% CI, -2.87 to -2.10) mEq/L. Clinics with a greater number of different dialysate sodium prescriptions (clinic 1, n=8; clinic 2, n=7) and that mixed dialysate concentrates on site had greater differences between prescribed and measured dialysate sodium concentrations. Overall, 57% of measured dialysate sodium concentrations were within ±2 mEq/L of the prescribed dialysate sodium concentration. Differences were greater at higher prescribed dialysate sodium concentrations. We only studied 4 facilities and dialysate delivery machines from 2 manufacturers. Because clinics using premixed dialysate used the same type of machine, we were unable to independently assess the impact of these factors. Pressures in dialysate delivery loops were not measured. There were significant differences between prescribed and measured dialysate sodium concentrations. This may have beneficial or deleterious effects on clinical outcomes, as well as confound results from studies assessing the

  17. Carbon Quantum Dot Surface-Engineered VO2 Interwoven Nanowires: A Flexible Cathode Material for Lithium and Sodium Ion Batteries.

    Science.gov (United States)

    Balogun, Muhammad-Sadeeq; Luo, Yang; Lyu, Feiyi; Wang, Fuxin; Yang, Hao; Li, Haibo; Liang, Chaolun; Huang, Miao; Huang, Yongchao; Tong, Yexiang

    2016-04-20

    The use of electrode materials in their powdery form requires binders and conductive additives for the fabrication of the cells, which leads to unsatisfactory energy storage performance. Recently, a new strategy to design flexible, binder-, and additive-free three-dimensional electrodes with nanoscale surface engineering has been exploited in boosting the storage performance of electrode materials. In this paper, we design a new type of free-standing carbon quantum dot coated VO2 interwoven nanowires through a simple fabrication process and demonstrate its potential to be used as cathode material for lithium and sodium ion batteries. The versatile carbon quantum dots that are vastly flexible for surface engineering serve the function of protecting the nanowire surface and play an important role in the diffusion of electrons. Also, the three-dimensional carbon cloth coated with VO2 interwoven nanowires assisted in the diffusion of ions through the inner and the outer surface. With this unique architecture, the carbon quantum dot nanosurface engineered VO2 electrode exhibited capacities of 420 and 328 mAh g(-1) at current density rate of 0.3 C for lithium and sodium storage, respectively. This work serves as a milestone for the potential replacement of lithium ion batteries and next generation postbatteries.

  18. Formation of a sodium bicarbonate cluster in the structure of sodium-substituted hydroxyapatite

    Science.gov (United States)

    Tkachenko, M. V.; Kamzin, A. S.

    2015-02-01

    Ceramic sodium-substituted carbonated hydroxyapatite has been synthesized using the method of the solid-phase reaction in the temperature range of 640-820°C in water vapor. It has been established that substitutions of Ca2+ ions in the cation and anion subsystems with Na+ ions and the PO{4/3-} and OH- groups with CO{3/2-} ions lead to a considerable acceleration of the shrinkage and synthesis of dense ceramics at substantially lower temperatures than in the case of unsubstituted hydroxyapatite. Sintering in water vapor leads to densification of carbonate groups in channel positions, which induces the appearance of orderings of A2 and B2 types (bands with wave numbers 867 and 865 cm-1 in IR spectra, respectively) as well as the protonation of carbonate groups both in A and B sites and the formation of sodium bicarbonate clusters (856 and 859 cm-1) in addition to carbonate ordering of A1 and B1 types (879 and 872 cm-1).

  19. Hydraulic conductivity in response to exchangeable sodium percentage and solution salt concentration

    Directory of Open Access Journals (Sweden)

    Jefferson Luiz de Aguiar Paes

    2014-10-01

    Full Text Available Hydraulic conductivity is determined in laboratory assays to estimate the flow of water in saturated soils. However, the results of this analysis, when using distilled or deionized water, may not correspond to field conditions in soils with high concentrations of soluble salts. This study therefore set out to determine the hydraulic conductivity in laboratory conditions using solutions of different electrical conductivities in six soils representative of the State of Pernambuco, with the exchangeable sodium percentage adjusted in the range of 5-30%. The results showed an increase in hydraulic conductivity with both decreasing exchangeable sodium percentage and increasing electrical conductivity in the solution. The response to the treatments was more pronounced in soils with higher proportion of more active clays. Determination of hydraulic conductivity in laboratory is routinely performed with deionized or distilled water. However, in salt affected soils, these determinations should be carried out using solutions of electrical conductivity different from 0 dS m-1, with values close to those determined in the saturation extracts.

  20. Comparison of sodium carbonate pretreatment for enzymatic hydrolysis of wheat straw stem and leaf to produce fermentable sugars.

    Science.gov (United States)

    Jin, Yongcan; Huang, Ting; Geng, Wenhui; Yang, Linfeng

    2013-06-01

    The specific characteristics of biomass structure and chemical composition of straw stem and leaf may result in different behavior of pretreatment and enzymatic hydrolysis. In this work, sodium carbonate (SC) was employed as a pretreatment to improve the enzymatic digestibility of wheat straw. The chemical composition and enzymatic hydrolysis of wheat straw stem and leaf (sheath included) were investigated comparatively. Most of the polysaccharides are kept in the solid fractions after SC pretreatment, while the stem has better delignification selectivity than leaf at high temperature. The enzymatic hydrolysis efficiency of wheat straw leaf is significantly higher than that of stem. The maximum total sugar yield from SC pretreated leaf was about 16% higher than stem. The results show that sodium carbonate is of great potential to be used as a pretreatment for the production of bioethanol from straw handling waste in a straw pulp mill with a low feedstock cost. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Detection Test for Leakage of CO2 into Sodium Loop

    International Nuclear Information System (INIS)

    Park, Sun Hee; Wi, Myung-Hwan; Min, Jae Hong

    2015-01-01

    This report is about the facility for the detection test for leakage of CO 2 into sodium loop. The facility for the detection test for leakage of CO 2 into sodium loop was introduced. The test will be carried out. Our experimental results are going to be expected to be used for approach methods to detect CO 2 leaking into sodium in heat exchangers. A sodium-and-carbon dioxide (Na-CO 2 ) heat exchanger is one of the key components for the supercritical CO 2 Brayton cycle power conversion system of sodium-cooled fast reactors (SFRs). A printed circuit heat exchanger (PCHE) is considered for the Na-CO 2 heat exchanger, which is known to have potential for reducing the volume occupied by the exchangers compared to traditional shell-and-tube heat exchangers. Among various issues about the Na- CO 2 exchanger, detection of CO 2 leaking into sodium in the heat exchanger is most important thing for its safe operation. It is known that reaction products from sodium and CO 2 such as sodium carbonate (Na 2 CO 3 ) and amorphous carbon are hardly soluble in sodium, which cause plug sodium channels. Detection technique for Na 2 CO 3 in sodium loop has not been developed yet. Therefore, detection of CO 2 and CO from reaction of sodium and CO 2 are proper to detect CO 2 leakage into sodium loop

  2. Zinc sorption in two vertisol and one aridisol series as affected by electrolyte concentration and sodium adsorption ratio

    International Nuclear Information System (INIS)

    Hussein, A. A.; Elamin, E. A.; El Mahi, Y. E.

    2002-01-01

    The effects of electrolyte concentration (C) and sodium adsorption ratio (SAR) on zinc sorption was studied. Top soil samples (0-30 cm) were taken from soils representing three arid-zon smectitc sites in the Gezira Scheme (Sudan). The orders of these soils are vertisol (El-Hosh (now Wad El Ataya) and El-Suleimi) and aridisol (El-Laota). These soils had no previous history of zinc application, and were previously equilibrated with mixed NaCl-CaCl 2 solutions to render different levels of SAR and salt concentration. Zinc retention decreased as electrolyte concentration increased, where maximum sorption occurred at low electrolyte concentration soils having high pH and high negative charge. Sodium adsorption ratio had little effect on Zn sorption as precipitation prevailed at high pH. It was also found that the sorption capacity of three soils were similar despite the variation in CaCO 3 and clay contents, hence cation exchange capacity and surface area. The results indicated that Zn was more soluble in the saline phases of Gezira soils, whereas sodicity had little effect.(Author)

  3. A high energy and power sodium-ion hybrid capacitor based on nitrogen-doped hollow carbon nanowires anode

    Science.gov (United States)

    Li, Dongdong; Ye, Chao; Chen, Xinzhi; Wang, Suqing; Wang, Haihui

    2018-04-01

    The sodium ion hybrid capacitor (SHC) has been attracting much attention. However, the SHC's power density is significantly confined to a low level due to the sluggish ion diffusion in the anode. Herein, we propose to use an electrode with a high double layer capacitance as the anode in the SHC instead of insertion anodes. To this aim, nitrogen doped hollow carbon nanowires (N-HCNWs) with a high specific surface area are prepared, and the high capacitive contribution during the sodium ion storage process is confirmed by a series of electrochemical measurements. A new SHC consisting of a N-HCNW anode and a commercial active carbon (AC) cathode is fabricated for the first time. Due to the hybrid charge storage mechanism combining ion insertion and capacitive process, the as-fabricated SHC strikes a balance between the energy density and power density, a energy density of 108 Wh kg-1 and a power density of 9 kW kg-1 can be achieved, which overwhelms the electrochemical performances of most reported AC-based SHCs.

  4. Adsorption of sodium dodecylbenzenesulfonate on activated carbons: effects of solution chemistry and presence of bacteria.

    Science.gov (United States)

    Bautista-Toledo, M I; Méndez-Díaz, J D; Sánchez-Polo, M; Rivera-Utrilla, J; Ferro-García, M A

    2008-01-01

    The objective of the present investigation was to determine the effectiveness of activated carbon in removing sodium dodecylbenzenesulfonate (SDBS) and to analyze the chemical and textural characteristics of the activated carbons that are involved in the adsorption process. Studies were also performed on the influence of operational variables (pH, ionic strength, and presence of microorganisms) and on the kinetics and interactions involved in the adsorption of this pollutant on activated carbon. The kinetics study of SDBS adsorption revealed no problems in its diffusion on any of the activated carbons studied, and Weisz-Prater coefficient (C WP) values were considerably lower than unity for all activated carbons studied. SDBS adsorption isotherms on these activated carbons showed that: (i) adsorption capacity of activated carbons was very high (260-470 mg/g) and increased with larger surface area; and (ii) dispersive interactions between SDBS and carbon surface were largely responsible for the adsorption of this pollutant. SDBS adsorption was not significantly affected by the solution pH, indicating that electrostatic adsorbent-adsorbate interactions do not play an important role in this process. The presence of electrolytes (NaCl) in the medium favors SDBS adsorption, accelerating the process and increasing adsorption capacity. Under the working conditions used, SDBS is not degraded by bacteria; however, the presence of bacteria during the process accelerates and increases SDBS adsorption on the activated carbon. Microorganism adsorption on the activated carbon surface increases its hydrophobicity, explaining the results observed.

  5. Activated carbons as potentially useful non-nutritive additives to prevent the effect of fumonisin B1 on sodium bentonite activity against chronic aflatoxicosis.

    Science.gov (United States)

    Monge, María Del Pilar; Magnoli, Alejandra Paola; Bergesio, Maria Virginia; Tancredi, Nestor; Magnoli, Carina E; Chiacchiera, Stella Maris

    2016-06-01

    Aflatoxin B1 (AFB1) and fumonisin B1 (FB1) are mycotoxins that often co-occur in feedstuffs. The ingestion of AFB1 causes aflatoxicosis in humans and animals. Sodium bentonite (NaB), a cheap non-nutritive unselective sequestering agent incorporated in animal diets, can effectively prevent aflatoxicosis. Fumonisins are responsible for equine leukoencephalomalacia and porcine pulmonary oedema, and often have subclinical toxic effects in poultries. Fumonisin B1 and aflatoxin B1 are both strongly adsorbed in vitro on sodium bentonite. Co-adsorption studies, carried out with a weight ratio of FB1 to AFB1 that mimics the natural occurrence (200:1), showed that FB1 greatly decreases the in vitro ability of NaB to adsorb AFB1. The ability of two activated carbons to adsorb FB1 was also investigated. Both carbons showed high affinity for FB1. A complex behaviour of the FB1 adsorption isotherms with pH was observed. In vitro results suggest that under natural contamination levels of AFB1 and FB1, a mixture of activated carbon and sodium bentonite might be potentially useful for prevention of sub-acute aflatoxicosis.

  6. Rational design of Sn/SnO{sub 2}/porous carbon nanocomposites as anode materials for sodium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiaojia [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Li, Xifei, E-mail: xfli2011@hotmail.com [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Center for Advanced Energy Materials and Devices, Xi’an University of Technology, Xi’an 710048 (China); Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin 300071 (China); Fan, Linlin; Yu, Zhuxin; Yan, Bo; Xiong, Dongbin; Song, Xiaosheng; Li, Shiyu [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Adair, Keegan R. [Nanomaterials and Energy Lab., Department of Mechanical and Materials Engineering, Western University, London, Ontario N6A 5B9 (Canada); Li, Dejun, E-mail: dejunli@mail.tjnu.edu.cn [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Sun, Xueliang, E-mail: xsun9@uwo.ca [Nanomaterials and Energy Lab., Department of Mechanical and Materials Engineering, Western University, London, Ontario N6A 5B9 (Canada); Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China)

    2017-08-01

    Highlights: • Sn/SnO{sub 2}/porous carbon nanocomposites are rationally designed via a facile strategy. • The porous carbon mitigates the volume change and poor conductivity of Sn/SnO{sub 2}. • The nanocomposites exhibit the enhanced sodium storage performance. - Abstract: Sodium-ion batteries (SIBs) have successfully attracted considerable attention for application in energy storage, and have been proposed as an alternative to lithium ion batteries (LIBs) due to the abundance of sodium resources and low price. Sn has been deemed as a promising anode material in SIBs which holds high theoretical specific capacity of 845 mAh g{sup −1}. In this work we design nanocomposite materials consisting of porous carbon (PC) with SnO{sub 2} and Sn (Sn/SnO{sub 2}/PC) via a facile reflux method. Served as an anode material for SIBs, the Sn/SnO{sub 2}/PC nanocomposite delivers the primary discharge and charge capacities of 1148.1 and 303.0 mAh g{sup −1}, respectively. Meanwhile, it can preserve the discharge capacity approximately of 265.4 mAh g{sup −1} after 50 cycles, which is much higher than those of SnO{sub 2}/PC (138.5 mAh g{sup −1}) and PC (92.2 mAh g{sup −1}). Furthermore, the Sn/SnO{sub 2}/PC nanocomposite possesses better cycling stability with 77.8% capacity retention compared to that of SnO{sub 2}/PC (61.88%) over 50 cycles. Obviously, the Sn/SnO{sub 2}/PC composite with excellent electrochemical performance shows the great possibility of application in SIBs.

  7. The dismantling of fast reactors: sodium processing

    International Nuclear Information System (INIS)

    Rodriguez, G.; Berte, M.; Serpante, J.P.

    1999-01-01

    Fast reactors require a coolant that does not slow down neutrons so water can not be used. Metallic sodium has been chosen because of its outstanding neutronic and thermal properties but sodium reacts easily with air and water and this implies that sodium-smeary components can not be considered as usual nuclear wastes. A stage of sodium neutralizing is necessary in the processing of wastes from fast reactors. Metallic sodium is turned into a chemically stable compound: soda, carbonates or sodium salts. This article presents several methods used by Framatome in an industrial way when dismantling sodium-cooled reactors. (A.C.)

  8. Enhanced osteoconductivity of sodium-substituted hydroxyapatite by system instability.

    Science.gov (United States)

    Sang Cho, Jung; Um, Seung-Hoon; Su Yoo, Dong; Chung, Yong-Chae; Hye Chung, Shin; Lee, Jeong-Cheol; Rhee, Sang-Hoon

    2014-07-01

    The effect of substituting sodium for calcium on enhanced osteoconductivity of hydroxyapatite was newly investigated. Sodium-substituted hydroxyapatite was synthesized by reacting calcium hydroxide and phosphoric acid with sodium nitrate followed by sintering. As a control, pure hydroxyapatite was prepared under identical conditions, but without the addition of sodium nitrate. Substitution of calcium with sodium in hydroxyapatite produced the structural vacancies for carbonate ion from phosphate site and hydrogen ion from hydroxide site of hydroxyapatite after sintering. The total system energy of sodium-substituted hydroxyapatite with structural defects calculated by ab initio methods based on quantum mechanics was much higher than that of hydroxyapatite, suggesting that the sodium-substituted hydroxyapatite was energetically less stable compared with hydroxyapatite. Indeed, sodium-substituted hydroxyapatite exhibited higher dissolution behavior of constituent elements of hydroxyapatite in simulated body fluid (SBF) and Tris-buffered deionized water compared with hydroxyapatite, which directly affected low-crystalline hydroxyl-carbonate apatite forming capacity by increasing the degree of apatite supersaturation in SBF. Actually, sodium-substituted hydroxyapatite exhibited markedly improved low-crystalline hydroxyl-carbonate apatite forming capacity in SBF and noticeably higher osteoconductivity 4 weeks after implantation in calvarial defects of New Zealand white rabbits compared with hydroxyapatite. In addition, there were no statistically significant differences between hydroxyapatite and sodium-substituted hydroxyapatite on cytotoxicity as determined by BCA assay. Taken together, these results indicate that sodium-substituted hydroxyapatite with structural defects has promising potential for use as a bone grafting material due to its enhanced osteoconductivity compared with hydroxyapatite. © 2013 Wiley Periodicals, Inc.

  9. Excess Sodium Tetraphenylborate and Intermediates Decomposition Studies

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, M.J.

    1998-12-07

    The stability of excess amounts of sodium tetraphenylborate (NaTPB) in the In-Tank Precipitation (ITP) facility depends on a number of variables. Concentration of palladium, initial benzene, and sodium ion as well as temperature provide the best opportunities for controlling the decomposition rate. This study examined the influence of these four variable on the reactivity of palladium-catalyzed sodium tetraphenylborate decomposition. Also, single effects tests investigated the reactivity of simulants with continuous stirring and nitrogen ventilation, with very high benzene concentrations, under washed sodium concentrations, with very high palladium concentrations, and with minimal quantities of excess NaTPB.

  10. Reaction of Hydrogen Chloride Gas with Sodium Carbonate and Its Deep Removal in a Fixed-Bed Reactor

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Svoboda, Karel; Pohořelý, Michael; Šyc, Michal; Chen, Po-Ch.

    2014-01-01

    Roč. 53, č. 49 (2014), s. 19145-19158 ISSN 0888-5885 R&D Projects: GA ČR GC14-09692J Grant - others:NSC(TW) 102WBS0300011 Institutional support: RVO:67985858 Keywords : hot fuel gas purification * hydrogen chloride gas * active sodium carbonate Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.587, year: 2014

  11. Recommended oral sodium bicarbonate administration for urine alkalinization did not affect the concentration of mitomycin-C in non-muscle invasive bladder cancer patients.

    Science.gov (United States)

    Seo, Ho Kyung; Kim, Sung Han; Ahn, Kyung-Ohk; Lee, Sang-Jin; Park, Weon Seo; Kim, Sohee; Hwang, Sang-Hyun; Lee, Do Hoon; Joung, Jae Young; Chung, Jinsoo; Joo, Jungnam; Jeong, Kyung-Chae

    2017-11-10

    Sodium bicarbonate has been reported to maximize the efficacy of intravesical instillation of mitomycin-C (IVI-MMC) therapy by urine alkalinization in non-muscle-invasive bladder cancer (NMIBC). This study aimed to analyze the changes in MMC concentration according to urinary pH and evaluate the efficacy of sodium bicarbonate to maintain the concentration of active form of MMC during IVI-MMC. We prospectively enrolled 26 patients with NMIBC after transurethral resection of bladder tumor. Patients with very high-risk and low-risk NMIBC were excluded. Urinary creatinine, volume, pH, and concentrations of MMC and its degraded form were measured immediately before and after IVI-MMC. The patients were administered 1.5 g of oral sodium bicarbonate during the preceding evening, in the morning, and immediately before the fourth cycle of the six-cycle IVI-MMC. The correlation between MMC concentration and urinary pH changes was explored with or without oral bicarbonate therapy. Recurrence without progression to muscle-invasive disease was noted in 4 of 26 patients in a 23.7-month follow-up. The mean urinary pH before and after the therapy increased from 6.03 to 6.50, and 6.46 to 7.24, without or with oral SB therapy, respectively. Despite this increase, the concentration of active form of MMC did not change significantly. No correlation was found between urinary pH and MMC concentration. Urine alkalinization by SB administration did not maintain the high concentration of urinary MMC. Urine alkalinization by sodium bicarbonate administration for IVI-MMC did not maintain the high concentration of active urinary MMC in NMIBC.

  12. Atmospheric dispersion of sodium aerosol due to a sodium leak in a fast breeder reactor complex

    International Nuclear Information System (INIS)

    Punitha, G.; Sudha, A. Jasmin; Kasinathan, N.; Rajan, M.

    2008-01-01

    Liquid sodium at high temperatures (470 K to 825 K) is used as the primary and secondary coolant in Liquid Metal cooled Fast Breeder Reactors (LMFBR). In the event of a postulated sodium leak in the Steam Generator Building (SGB) of a LMFBR, sodium readily combusts in the ambient air, especially at temperatures above 523 K. Intense sodium fire results and sodium oxide fumes are released as sodium aerosols. Sodium oxides are readily converted to sodium hydroxide in air due to the presence of moisture in it. Hence, sodium aerosols are invariably in the form of particulate sodium hydroxide. These aerosols damage not only the equipment and instruments due to their corrosive nature but also pose health hazard to humans. Hence, it is essential to estimate the concentration of sodium aerosols within the plant boundary for a sodium leak event. The Gaussian Plume Dispersion Model can obtain the atmospheric dispersion of sodium aerosols in an open terrain. However, this model dose not give accurate results for dispersion in spaces close to the point of release and with buildings in between. The velocity field due to the wind is altered to a large extent by the intervening buildings and structures. Therefore, a detailed 3-D estimation of the velocity field and concentration has to be obtained through rigorous computational fluid dynamics (CFD) approach. PHOENICS code has been employed to determine concentration of sodium aerosols at various distances from the point of release. The dispersion studies have been carried out for the release of sodium aerosols at different elevations from the ground and for different wind directions. (author)

  13. Effect of carbonic anhydrase on silicate weathering and carbonate formation at present day CO₂ concentrations compared to primordial values.

    Science.gov (United States)

    Xiao, Leilei; Lian, Bin; Hao, Jianchao; Liu, Congqiang; Wang, Shijie

    2015-01-13

    It is widely recognized that carbonic anhydrase (CA) participates in silicate weathering and carbonate formation. Nevertheless, it is still not known if the magnitude of the effect produced by CA on surface rock evolution changes or not. In this work, CA gene expression from Bacillus mucilaginosus and the effects of recombination protein on wollastonite dissolution and carbonate formation under different conditions are explored. Real-time fluorescent quantitative PCR was used to explore the correlation between CA gene expression and sufficiency or deficiency in calcium and CO₂ concentration. The results show that the expression of CA genes is negatively correlated with both CO₂ concentration and ease of obtaining soluble calcium. A pure form of the protein of interest (CA) is obtained by cloning, heterologous expression, and purification. The results from tests of the recombination protein on wollastonite dissolution and carbonate formation at different levels of CO₂ concentration show that the magnitudes of the effects of CA and CO₂ concentration are negatively correlated. These results suggest that the effects of microbial CA in relation to silicate weathering and carbonate formation may have increased importance at the modern atmospheric CO₂ concentration compared to 3 billion years ago.

  14. Amorphous Red Phosphorus Embedded in Sandwiched Porous Carbon Enabling Superior Sodium Storage Performances.

    Science.gov (United States)

    Wu, Ying; Liu, Zheng; Zhong, Xiongwu; Cheng, Xiaolong; Fan, Zhuangjun; Yu, Yan

    2018-03-01

    The red P anode for sodium ion batteries has attracted great attention recently due to the high theoretical capacity, but the poor intrinsic electronic conductivity and large volume expansion restrain its widespread applications. Herein, the red P is successfully encapsulated into the cube shaped sandwich-like interconnected porous carbon building (denoted as P@C-GO/MOF-5) via the vaporization-condensation method. Superior cycling stability (high capacity retention of about 93% at 2 A g -1 after 100 cycles) and excellent rate performance (502 mAh g -1 at 10 A g -1 ) can be obtained for the P@C-GO/MOF-5 electrode. The superior electrochemical performance can be ascribed to the successful incorporation of red P into the unique carbon matrix with large surface area and pore volume, interconnected porous structure, excellent electronic conductivity and superior structural stability. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Removal of sodium from the component of the sodium purification loop

    International Nuclear Information System (INIS)

    Kim, Byung Ho; Jeong, Kyung Chai; Jeong, Ji Young; Kim, Jong Man; Choi, Byung Hae; Nam, Ho Yun

    2005-01-01

    The purpose of a cleaning process is to remove the residual sodium adhering to the component walls once it has been properly drained. It is necessary to clean and decontaminate a component, especially the large components of the primary coolant system; such as the intermediate heat exchangers and the primary pump. Improper and inadequate cleaning has in a number of cases resulted in problems in the storage, handling, and reuse of components. Several types of failures due to improper cleaning procedures have been defined in the past. Inadequate and incomplete removal of sodium results in residues which may contain metallic sodium and alkaline compounds such as sodium hydroxide, sodium oxide, sodium carbonate, and various types of alcoholates. Reinsertion of components containing these compounds into a high-temperature sodium system can result in either the intergranular penetration characteristic of a high-oxygen sodium or an accelerated corrosion due to oxygen. The methods used for cleaning sodium equipment depend on the condition and types of equipment to be cleaned and whether the equipment is to be reused. Cleaning methods are needed that will avoid a deleterious local overheating, material surface degradation or deposits, chemical, physical, or mechanical damage, and external effects. This paper discusses a steam-nitrogen gas cleaning method for the routine applications that permits the reuse of the cold trap in sodium

  16. A 5-day method for determination of soluble silicon concentrations in nonliquid fertilizer materials using a sodium carbonate-ammonium nitrate extractant followed by visible spectroscopy with heteropoly blue analysis: single-laboratory validation.

    Science.gov (United States)

    Sebastian, Dennis; Rodrigues, Hugh; Kinsey, Charles; Korndörfer, Gaspar; Pereira, Hamilton; Buck, Guilherme; Datnoff, Lawrence; Miranda, Stephen; Provance-Bowley, Mary

    2013-01-01

    A 5-day method for determining the soluble silicon (Si) concentrations in nonliquid fertilizer products was developed using a sodium carbonate (Na2CO3)-ammonium nitrate (NH4NO3) extractant followed by visible spectroscopy with heteropoly blue analysis at 660 nm. The 5-Day Na2CO3-NH4NO3 Soluble Si Extraction Method can be applied to quantify the plant-available Si in solid fertilizer products at levels ranging from 0.2 to 8.4% Si with an LOD of 0.06%, and LOQ of 0.20%. This Si extraction method for fertilizers correlates well with plant uptake of Si (r2 = 0.96 for a range of solid fertilizers) and is applicable to solid Si fertilizer products including blended products and beneficial substances. Fertilizer materials can be processed as received using commercially available laboratory chemicals and materials at ambient laboratory temperatures. The single-laboratory validation of the 5-Day Na2CO3-NH4NO3 Soluble Si Extraction Method has been approved by The Association of American Plant Food Control Officials for testing nonliquid Si fertilizer products.

  17. SnSe/carbon nanocomposite synthesized by high energy ball milling as an anode material for sodium-ion and lithium-ion batteries

    International Nuclear Information System (INIS)

    Zhang, Zhian; Zhao, Xingxing; Li, Jie

    2015-01-01

    Graphical abstract: A homogeneous nanocomposite of SnSe and carbon black was synthesised by high energy ball milling and empolyed as an anode material for sodium-ion batteries (SIBs) and lithium-ion batteries (LIBs). The nanocomposite anode exhibits excellent electrochemical performances in both SIBs and LIBs. - Highlights: • A homogeneous nanocomposite of SnSe and carbon black was fabricated by high energy ball milling. • SnSe and carbon black are homogeneously mixed at the nanoscale level. • The SnSe/C anode exhibits excellent electrochemical performances in both SIBs and LIBs. - Abstract: A homogeneous nanocomposite of SnSe and carbon black, denoted as SnSe/C nanocomposite, was fabricated by high energy ball milling and empolyed as a high performance anode material for both sodium-ion batteries and lithium-ion batteries. The X-ray diffraction patterns, scanning electron microscopy and transmission electron microscopy observations confirmed that SnSe in SnSe/C nanocomposite was homogeneously distributed within carbon black. The nanocomposite anode exhibited enhanced electrochemical performances including a high capacity, long cycling behavior and good rate performance in both sodium-ion batteries (SIBs) and lithium-ion batteries (LIBs). In SIBs, an initial capacitiy of 748.5 mAh g −1 was obtained and was maintained well on cycling (324.9 mAh g −1 at a high current density of 500 mA g −1 in the 200 th cycle) with 72.5% retention of second cycle capacity (447.7 mAh g −1 ). In LIBs, high initial capacities of approximately 1097.6 mAh g −1 was obtained, and this reduced to 633.1 mAh g −1 after 100 cycles at 500 mA g −1

  18. Muzzle secretion electrolytes as a possible indicator of sodium status in buffalo (Bubalus bubalis) calves: effects of sodium depletion and aldosterone administration.

    Science.gov (United States)

    Kumar, S; Singh, S P

    1981-01-01

    In two separate experiments, the effects of sodium depletion and aldosterone administration on sodium and potassium concentrations in muzzle secretion, saliva and urine were studied in buffalo calves. Sodium deficiency in the animals was experimentally produced by unilateral parotid saliva deprivation for 18 days. During sodium depletion, the sodium levels in saliva and muzzle secretion gradually fell while the potassium level gradually rose. The concentrations of both of these cations in urine gradually fell during the course of sodium depletion. Aldosterone administration in normal (sodium-replete) animals simulated the effects of sodium depletion as far as cationic changes in saliva were concerned. However, aldosterone did not affect sodium and potassium concentration in the urine and in muzzle secretion in a manner similar to that caused by sodium depletion. Though the hormone decreased urinary sodium without affecting urinary potassium, it did not affect the muzzle sodium or potassium. Results suggest that aldosterone affects the composition of saliva and urine in buffaloes as it does in sheep and other ruminants. Similar changes in composition of muzzle secretion and saliva during sodium depletion indicate that the concentration of sodium in muzzle secretion could possibly be used to evaluate the sodium status of animals.

  19. Structural study of concentrated micelle-solutions of sodium octanoate by light scattering

    International Nuclear Information System (INIS)

    Hayoun, Marc

    1982-05-01

    Structural investigation of sodium octanoate (CH 3 -(CH 2 ) 6 -COONa) by light scattering has been made to study properties of concentrated aqueous micelle-solutions. From static light scattering data, the micellar weight and shape have been determined. The monomer aggregation number and the apparent micellar charge have been confirmed. Quasi-elastic light scattering, has been used to measure the effective diffusion coefficient as a function of the volume fraction. Extrapolation to the c.m.c. give the hydrodynamic radius of the micelles. At low micelle-concentration, strong exchange reaction between monomers and micelles affects the Brownian motion and resulting is an increase in the diffusion coefficient. The experimental data show a strong hydrodynamic contribution to S(q) (factor structure) and D(q) (effective diffusion coefficient) arising from hard spheres interactions with a large repulsive potential. (author) [fr

  20. Mesoporous-activated carbon prepared from chitosan flakes via single-step sodium hydroxide activation for the adsorption of methylene blue.

    Science.gov (United States)

    Marrakchi, F; Ahmed, M J; Khanday, W A; Asif, M; Hameed, B H

    2017-05-01

    In this work, mesoporous-activated carbon (CSAC) was prepared from chitosan flakes (CS) via single-step sodium hydroxide activation for the adsorption of methylene blue (MB). CSAC was prepared using different impregnation ratios of NaOH:CS (1:1, 2:1, 3:1, and 4:1) at 800°C for 90min. The adsorption performance of CSAC was evaluated for MB at different adsorption variables, such MB initial concentrations (25-400mg/L), solution pH (3-11), and temperature (30-50°C). The adsorption isotherm data of CSAC-MB were well fitted to Langmuir model with a maximum adsorption capacity 143.53mg/g at 50°C. Best representation of kinetic data was obtained by the pseudo-second order model. CSAC exhibited excellent adsorption uptake for MB and can potentially be used for other cationic dyes. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Estimating Terrestrial Wood Biomass from Observed Concentrations of Atmospheric Carbon Dioxide

    NARCIS (Netherlands)

    Schaefer, K. M.; Peters, W.; Carvalhais, N.; van der Werf, G.; Miller, J.

    2008-01-01

    We estimate terrestrial disequilibrium state and wood biomass from observed concentrations of atmospheric CO2 using the CarbonTracker system coupled to the SiBCASA biophysical model. Starting with a priori estimates of carbon flux from the land, ocean, and fossil fuels, CarbonTracker estimates net

  2. Stability of aqueous-alkaline sodium borohydride formulations

    International Nuclear Information System (INIS)

    Minkina, V.G.; Shabunya, S.I.; Kalinin, V.I.; Martynenko, V.V.

    2008-01-01

    Stability of sodium borohydride in the form of concentrated solutions and suspensions and solids corresponding to a crystal hydrate in composition was studied. The effects of temperature, concentrations of sodium borohydride and alkali, and nature of alkali metal cation on the rate of sodium borohydride hydrolysis were studied [ru

  3. Characterization of Black and Brown Carbon Concentrations and Sources during winter in Beijing

    Science.gov (United States)

    Yan, Caiqing; Liu, Yue; Hansen, Anthony D. A.; Močnik, Griša; Zheng, Mei

    2017-04-01

    Carbonaceous aerosols, including black carbon (BC) and organic carbon (OC), play important roles in air quality, human health, and climate change. A better understanding of sources of light-absorbing carbonaceous aerosol (including black carbon and brown carbon) is particular critical for formulating emission-based control strategies and reducing uncertainties in current aerosol radiative forcing estimates. Beijing, the capital of China, has experienced serious air pollution problems and high concentrations of carbonaceous aerosols in recent years, especially during heating seasons. During November and December of 2016, several severe haze episodes occurred in Beijing, with hourly average PM2.5 mass concentration up to 400 μg/m3. In this study, concentration levels and sources of black carbon and brown carbon were investigated based on 7-wavelength Aethalometer (AE-33) with combination of other PM2.5 chemical composition information. Contributions of traffic and non-traffic emissions (e.g., coal combustion, biomass burning) were apportioned, and brown carbon was separated from black carbon. Our preliminary results showed that (1) Concentrations of BC were around 5.3±4.2 μg/m3 during the study period, with distinct diurnal variations during haze and non-haze days. (2) Traffic emissions contributed to about 37±17% of total BC, and exhibited higher contributions during non-haze days compared to haze days. (3) Coal combustion was a major source of black carbon and brown carbon in Beijing, which was more significant compared to biomass burning. Sources and the relative contributions to black carbon and brown carbon during haze and non-haze days will be further discussed.

  4. Uranium recovery by leaching with sodium carbonate at high temperature and pressure

    International Nuclear Information System (INIS)

    Soerensen, E.; Koefoed, S.; Lundgaard, T.

    1990-09-01

    An alkaline rock from the Ilimaussaq instrusion, SW Greenland, was proposed as a source of uranium. Its principal uranium bearing mineral, Steenstrupine, is a complex sodium REE phosphosilicate in which Fe, Mn, Th and U are minor constituents. A special feature of this ore body is the content of water soluble minerals: NaF (Villiaumite), Na 2 Si 2 O 5 (Natrosilite) and an organic substance which displays the characteristics of humus. Sulfides are sparse, the most important one being ZnS (Sphalerite) of which the content is generally less than 0.5%. In the mineral under consideration (Lujavrite) the Steenstrupine is mainly finelay disseminated throughout the rock, yielding a uranium content of 300-400 ppm and thorium content of 800-1000 ppm. Laboratory tests indicated that high temperature carbonate leaching was necessary to decompose Steenstrupine. The optium temperature was shown to be 260 deg. C and the leach liquor composition 120 g/l of NaHCO 3 and 20 g/l of Na 2 C0 3 . Addition of oxygen is necessary. The process was developed to industrial scale in a continuous pipe autoclave with a retention time of 20 min. After filtering on a belt filter, the liquor was recycled several times to obtain a higher U-concentration. By reductive precipitation with iron powder a raw UO 2 was obtained. It was purified after dissolution in HNO 3 . An overall yield of 80% could be obtained. (author) 32 tabs., 13 ills., 24 refs

  5. Lack of Effect of Sodium Benzoate at Reported Clinical Therapeutic Concentration on d-Alanine Metabolism in Dogs.

    Science.gov (United States)

    Popiolek, Michael; Tierney, Brendan; Steyn, Stefanus J; DeVivo, Michael

    2018-06-19

    Cognitive decline and psychosis have been hypothesized to be mediated by N-methyl-d-aspartate receptor (NMDAR) hypofunction. Consistent with this hypothesis, chronic treatment with d-alanine, a coagonist at the glycine site of the NMDAR, leads to an improvement of positive and cognitive symptoms in schizophrenic patients. d-alanine is oxidized by d-amino acid oxidase (DAAO); thus, an inhibitor of DAAO would be expected to enhance d-alanine levels and likewise lead to desirable clinical outcomes. Sodium benzoate, on the basis of d-amino acid inhibition, was observed to display beneficial clinical effects in schizophrenic and Alzheimer's patients. However, in the clinical pilot studies using sodium benzoate, d-amino acids were not quantified to verify that sodium benzoate's efficacy was mediated through DAAO inhibition. In this study, d-alanine content was monitored in cerebral spinal fluid (CSF) of dogs treated with daily injections of d-alanine (30 mg/kg) alone and in combination with sodium benzoate (30 mg/kg) for seven consecutive days. We reasoned that the cerebral spinal fluid d-alanine quantity is reflective of the brain d-alanine levels and it would increase as a consequence of DAAO inhibition with sodium benzoate. We found that d-alanine treatment lead to maximal concentration of 7.51 μM CSF d-alanine level; however, coadministration of sodium benzoate and d-alanine did not change CSF d-alanine level beyond that of d-alanine treatment alone. As a consequence, we conclude that clinical efficacy associated with chronic administration of sodium benzoate in schizophrenic and Alzheimer's patients is likely not mediated through inhibition of DAAO.

  6. Assurance of sodium concentration measurement on line in water supply to the secondary system in Atucha I and II nuclear power plants

    International Nuclear Information System (INIS)

    Ormando, Miguel-Angel; Galarza, Guillermo-Dario

    2012-09-01

    Sodium measurement is used for quality control in high purity water application, to monitor break-through of mixed bed ion exchanger, condenser leaks and also to prevent caustic corrosion in turbines. The measurement principle is based on a selective electrode that responds to Nernst equation. The samples were measured in Swan's Trace Sodium/Conductivity Analyzer, Model 2114 July 1993. The aim of this work was to present a method in order to assure sodium concentration measurement on line using the ion selective method for water supply to the secondary system. Conductivity, less sensitive but more reliable than sodium analysis, is an overall quality parameter of water. It is traditionally used to back-up sodium analyzer and is sensitive to any ionic impurities. (authors)

  7. Study the Properties of Sodium Silicate Composite as a Barrier Separating Between the Internal Oil Distillation Towers and Chemical Fumes of Crude Oil

    Directory of Open Access Journals (Sweden)

    سلام حسين علي

    2016-07-01

    Full Text Available The study of surface hardness, wear resistance, adhesion strength, electrochemical corrosion resistance and thermal conductivity of coatings composed from sodium silicate was prepared using graphite micro-size particles and carbon nano particles as fillers respectively of concentration of (1-5%, for the purpose of covering and protecting the oil distillation towers. The results showed that the sodium silicate coating reinforced with carbon nano-powder has higher resistance to stitches, mechanical wear, adhesive and thermal conductivity than graphite/sodium silicate composite especially when the ratio 5% and 1%, the electrochemical corrosion test confirmed that the coating process of stainless steel 304 lead to increasing the corrosion resistance, where the reinforcing of sodium silicate lead to a significant improvement in the corrosion resistance, the corrosion resistance behavior change depending on the type of reinforcement material, this is consistent with the field test results.

  8. N/S Co-Doped 3 D Porous Carbon Nanosheet Networks Enhancing Anode Performance of Sodium-Ion Batteries.

    Science.gov (United States)

    Zou, Lei; Lai, Yanqing; Hu, Hongxing; Wang, Mengran; Zhang, Kai; Zhang, Peng; Fang, Jing; Li, Jie

    2017-10-12

    A facile and scalable method is realized for the in situ synthesis of N/S co-doped 3 D porous carbon nanosheet networks (NSPCNNs) as anode materials for sodium-ion batteries. During the synthesis, NaCl is used as a template to prepare porous carbon nanosheet networks. In the resultant architecture, the unique 3 D porous architecture ensures a large specific surface area and fast diffusion paths of both electrons and ions. In addition, the import of N/S produces abundant defects, increased interlayer spacings, more active sites, and high electronic conductivity. The obtained products deliver a high specific capacity and excellent long-term cycling performance, specifically, a capacity of 336.2 mA h g -1 at 0.05 A g -1 , remaining as large as 214.9 mA h g -1 after 2000 charge/discharge cycles at 0.5 A g -1 . This material has great prospects for future applications of scalable, low-cost, and environmentally friendly sodium-ion batteries. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Continuing assessment of the 5 day sodium carbonate-ammonium nitrate extraction assay as an indicator test for silicon fertilizers

    Science.gov (United States)

    The five day sodium carbonate-ammonium nitrate extraction assay has been proposed by the AAFPCO as a standard test to identify fertilizers that provide plant-available Si. A single-lab validation test was previously performed; however, the analysis lacked any correlation to a grow-out study. To do...

  10. Antimicrobial Activity of Single-Walled Carbon Nanotubes Suspended in Different Surfactants

    Directory of Open Access Journals (Sweden)

    Lifeng Dong

    2012-01-01

    Full Text Available We investigated the antibacterial activity of single-walled carbon nanotubes (SWCNTs dispersed in surfactant solutions of sodium cholate, sodium dodecylbenzene sulfonate, and sodium dodecyl sulfate. Among the three surfactants, sodium cholate demonstrated the weakest antibacterial activity against Salmonella enterica, Escherichia coli, and Enterococcus faecium and thereby was used to disperse bundled SWCNTs in order to study nanotube antibiotic activity. SWCNTs exhibited antibacterial characteristics for both S. enterica and E. coli. With the increase of nanotube concentrations from 0.3 mg/mL to 1.5 mg/mL, the growth curves had plateaus at lower absorbance values whereas the absorbance value was not obviously affected by the incubation ranging from 5 min to 2 h. Our findings indicate that carbon nanotubes could become an effective alternative to antibiotics in dealing with drug-resistant and multidrug-resistant bacterial strains because of the physical mode of bactericidal action that SWCNTs display.

  11. Carbon dioxide sequestration using NaHSO4 and NaOH: A dissolution and carbonation optimisation study.

    Science.gov (United States)

    Sanna, Aimaro; Steel, Luc; Maroto-Valer, M Mercedes

    2017-03-15

    The use of NaHSO 4 to leach out Mg fromlizardite-rich serpentinite (in form of MgSO 4 ) and the carbonation of CO 2 (captured in form of Na 2 CO 3 using NaOH) to form MgCO 3 and Na 2 SO 4 was investigated. Unlike ammonium sulphate, sodium sulphate can be separated via precipitation during the recycling step avoiding energy intensive evaporation process required in NH 4 -based processes. To determine the effectiveness of the NaHSO 4 /NaOH process when applied to lizardite, the optimisation of the dissolution and carbonation steps were performed using a UK lizardite-rich serpentine. Temperature, solid/liquid ratio, particle size, concentration and molar ratio were evaluated. An optimal dissolution efficiency of 69.6% was achieved over 3 h at 100 °C using 1.4 M sodium bisulphate and 50 g/l serpentine with particle size 75-150 μm. An optimal carbonation efficiency of 95.4% was achieved over 30 min at 90 °C and 1:1 magnesium:sodium carbonate molar ratio using non-synthesised solution. The CO 2 sequestration capacity was 223.6 g carbon dioxide/kg serpentine (66.4% in terms of Mg bonded to hydromagnesite), which is comparable with those obtained using ammonium based processes. Therefore, lizardite-rich serpentinites represent a valuable resource for the NaHSO 4 /NaOH based pH swing mineralisation process. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Development of a sodium ionization detector for sodium-to-gas leaks

    International Nuclear Information System (INIS)

    Swaminathan, K.; Elumalai, G.

    1984-01-01

    A sensitive sodium-to-gas leak detector has been indigenously developed for use in liquid metal cooled fast breeder reactor. The detector relies on the relative ease with which sodium vapour or its aerosols including its oxides and hydroxides can be thermally ionized compared with other possible constituents such as nitrogen, oxygen, water vapour etc. in a carrier gas and is therefore called sodium ionization detector (SID). The ionization current is a measure of sodium concentration in the carrier gas sampled through the detector. Different sensor designs using platinum and rhodium as filament materials in varying sizes were constructed and their responses to different sodium aerosol concentrations in the carrier gas were investigated. Nitrogen was used as the carrier gas. Both the background current and speed of response were found to depend on the diameter of the filament. There was also a particular collector voltage which yielded maximum sensitivity of the detector. The sensor was therefore optimised considering influence of above factors and a detector has been built which demonstrates a sensitivity better than 0.3 nanogram of sodium per cubic centimetre of carrier gas for a signal to background ratio of 1:1. Its usefulness in detecting sodium fires in experimental area was also demonstrated. Currently efforts are under way to improve the life time of the filament used in the above detector. (author)

  13. The Sodium Process Facility at Argonne National Laboratory-West

    International Nuclear Information System (INIS)

    Michelbacher, J.A.; Henslee, S.P.; McDermott, M.D.; Price, J.R.; Rosenberg, K.E.; Wells, P.B.

    1998-01-01

    Argonne National Laboratory-West (ANL-W) has approximately 680,000 liters of raw sodium stored in facilities on site. As mandated by the State of Idaho and the US Department of Energy (DOE), this sodium must be transformed into a stable condition for land disposal. To comply with this mandate, ANL-W designed and built the Sodium Process Facility (SPF) for the processing of this sodium into a dry, sodium carbonate powder. The major portion of the sodium stored at ANL-W is radioactively contaminated. The sodium will be processed in three separate and distinct campaigns: the 290,000 liters of Fermi-1 primary sodium, the 50,000 liters of the Experimental Breeder Reactor-II (EBR-II) secondary sodium, and the 330,000 liters of the EBR-II primary sodium. The Fermi-1 and the EBR-II secondary sodium contain only low-level of radiation, while the EBR-II primary sodium has radiation levels up to 0.5 mSv (50 mrem) per hour at 1 meter. The EBR-II primary sodium will be processed last, allowing the operating experience to be gained with the less radioactive sodium prior to reacting the most radioactive sodium. The sodium carbonate will be disposed of in 270 liter barrels, four to a pallet. These barrels are square in cross-section, allowing for maximum utilization of the space on a pallet, minimizing the required landfill space required for disposal

  14. The Sodium Process Facility at Argonne National Laboratory-West

    Energy Technology Data Exchange (ETDEWEB)

    Michelbacher, J.A.; Henslee, S.P. McDermott, M.D.; Price, J.R.; Rosenberg, K.E.; Wells, P.B.

    1998-07-01

    Argonne National Laboratory-West (ANL-W) has approximately 680,000 liters of raw sodium stored in facilities on site. As mandated by the State of Idaho and the US Department of Energy (DOE), this sodium must be transformed into a stable condition for land disposal. To comply with this mandate, ANL-W designed and built the Sodium Process Facility (SPF) for the processing of this sodium into a dry, sodium carbonate powder. The major portion of the sodium stored at ANL-W is radioactively contaminated. The sodium will be processed in three separate and distinct campaigns: the 290,000 liters of Fermi-1 primary sodium, the 50,000 liters of the Experimental Breeder Reactor-II (EBR-II) secondary sodium, and the 330,000 liters of the EBR-II primary sodium. The Fermi-1 and the EBR-II secondary sodium contain only low-level of radiation, while the EBR-II primary sodium has radiation levels up to 0.5 mSv (50 mrem) per hour at 1 meter. The EBR-II primary sodium will be processed last, allowing the operating experience to be gained with the less radioactive sodium prior to reacting the most radioactive sodium. The sodium carbonate will be disposed of in 270 liter barrels, four to a pallet. These barrels are square in cross-section, allowing for maximum utilization of the space on a pallet, minimizing the required landfill space required for disposal.

  15. Effect of Na2CO3 degumming concentration on LiBr-formic acid-silk fibroin solution properties

    Directory of Open Access Journals (Sweden)

    Liu Zhi

    2016-01-01

    Full Text Available Salt-acid system has been proved to be of high efficiency for silk fibroin dissolution. Using salt-acid system to dissolve silk, native silk fibrils can be preserved in the regenerated solution. Increasing experiments indicate that acquirement of silk fibrils in solution is strongly associated with the degumming process. In this study, the effect of sodium carbonate degumming concentration on solution properties based on lithium bromide-formic acid dissolution system was systematically investigated. Results showed that the morphology transformation of silk fibroin in solution from nanospheres to nanofibrils is determined by sodium carbonate concentration during the degumming process. Solutions containing different silk fibroin structure exhibited different rheological behaviors and different electrospinnability, leading to different electrospun nanofibre properties. The results have guiding significance for preparation and application of silk fibroin solutions.

  16. Slicing sodium from bakery products

    NARCIS (Netherlands)

    Noort, M.

    2012-01-01

    The need for sodium reduction in our diet is clear to consumers, dieticians and food manufacturers. As sodium concentration has a strengthening effect on gluten, sodium reduction decreases dough mixing tolerance, dough resistance and induces dough stickiness. In particular, the latter may cause

  17. Self-doped carbon architectures with heteroatoms containing nitrogen, oxygen and sulfur as high-performance anodes for lithium- and sodium-ion batteries

    International Nuclear Information System (INIS)

    Lu, Mingjie; Yu, Wenhua; Shi, Jing; Liu, Wei; Chen, Shougang; Wang, Xin; Wang, Huanlei

    2017-01-01

    Highlights: •Self-doped carbon architectures with nitrogen, oxygen, and sulfur are derived from Carrageen. •The obtained carbon materials exhibit excellent electrochemical property. •The strategy provides a one-step synthesis route to design advanced anodes for batteries. -- Abstract: Nitrogen, oxygen and sulfur tridoped porous carbons have been successfully synthesized from natural biomass algae-Carrageen by using a simultaneous carbonization and activation procedure. The doped carbons with sponge-like interconnected architecture, partially ordered graphitic structure, and abundant heteroatom doping perform outstanding features for electrochemical energy storage. When tested as lithium-ion battery anodes, a high reversible capacity of 839 mAh g −1 can be obtained at the current density of 0.1 A g −1 after 100 cycles, while a high capacity of 228 mAh g −1 can be maintained at 10 A g −1 . Tested against sodium, a high specific capacity of 227 can be delivered at 0.1 A g −1 after 100 cycles, while a high capacity of 109 mAh g −1 can be achieved at 10 A g −1 . These results turn out that the doped carbons would be potential anode materials for lithium- and sodium-ion batteries, which can be achieved by a one-step and large-scale synthesis route. Our observation indicates that heteroatom doping (especially sulfur) can significantly promote ion storage and reduce irreversible ion trapping to some extent. This work gives a general route for designing carbon nanostructures with heteroatom doping for efficient energy storage.

  18. First principle study of sodium decorated graphyne

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Utpal, E-mail: utpalchemiitkgp@yahoo.com [Assam University, Silchar (India); Bhattacharya, Barnali [Assam University, Silchar (India); Seriani, Nicola [The Abdus Salam ICTP, Trieste (Italy)

    2015-11-05

    Highlights: • Presence of Na decreases the stability of the system. • Na-decorated graphyne compounds are metallic and might be used in electronics. • The sodium-adsorbed graphyne can be used as electrodes in Na-ion battery. - Abstract: We present first-principles calculations of the electronic properties of Na-decorated graphyne. This structure of the graphyne family is a direct band gap semiconductor with a band gap of 0.44 eV in absence of sodium, but Na-decorated graphyne compounds are metallic, and can then be employed as carbon-based conductors. Metallization is due to charge donation from sodium to carbon. Pristine graphyne is more stable than Na-decorated graphyne, therefore is seems probable that, if this material should be employed as electrode in Na-ion batteries, it would lead to the formation of metallic sodium rather than well dispersed sodium ions. On the other side, this property might be useful if graphyne is employed in water desalination. Finally, the abrupt change from a semiconducting to a metallic state in presence of a small amount of sodium might be exploited in electronics, e.g. for the production of smooth metal–semiconductor interfaces through spatially selective deposition of sodium.

  19. Dendrite-Free Sodium-Metal Anodes for High-Energy Sodium-Metal Batteries.

    Science.gov (United States)

    Sun, Bing; Li, Peng; Zhang, Jinqiang; Wang, Dan; Munroe, Paul; Wang, Chengyin; Notten, Peter H L; Wang, Guoxiu

    2018-05-31

    Sodium (Na) metal is one of the most promising electrode materials for next-generation low-cost rechargeable batteries. However, the challenges caused by dendrite growth on Na metal anodes restrict practical applications of rechargeable Na metal batteries. Herein, a nitrogen and sulfur co-doped carbon nanotube (NSCNT) paper is used as the interlayer to control Na nucleation behavior and suppress the Na dendrite growth. The N- and S-containing functional groups on the carbon nanotubes induce the NSCNTs to be highly "sodiophilic," which can guide the initial Na nucleation and direct Na to distribute uniformly on the NSCNT paper. As a result, the Na-metal-based anode (Na/NSCNT anode) exhibits a dendrite-free morphology during repeated Na plating and striping and excellent cycling stability. As a proof of concept, it is also demonstrated that the electrochemical performance of sodium-oxygen (Na-O 2 ) batteries using the Na/NSCNT anodes show significantly improved cycling performances compared with Na-O 2 batteries with bare Na metal anodes. This work opens a new avenue for the development of next-generation high-energy-density sodium-metal batteries. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Effect of Carbon Concentration on the Sputtering of Carbon-Rich SiC Bombarded by Helium Ions

    Directory of Open Access Journals (Sweden)

    Xinghao Liang

    2018-02-01

    Full Text Available Silicon carbide (SiC is considered as an important material for nuclear engineering due to its excellent properties. Changing the carbon content in SiC can regulate and control its elastic and thermodynamic properties, but a simulation study of the effect of carbon content on the sputtering (caused by the helium ions of SiC is still lacking. In this work, we used the Monte-Carlo and molecular dynamics simulation methods to study the effects of carbon concentration, incidence energy, incident angle, and target temperature on the sputtering yield of SiC. The results show that the incident ions’ energy and angle have a significant effect on sputtering yield of SiC when the carbon concentration in SiC is around 62 at %, while the target temperature has a little effect on the sputtering yield of SiC. Our work might provide theoretical support for the experimental research and engineering application of carbon fiber-reinforced SiC that be used as the plasma-facing material in tokamak fusion reactors.

  1. A Patient with MSUD: Acute Management with Sodium Phenylacetate/Sodium Benzoate and Sodium Phenylbutyrate

    OpenAIRE

    K?se, Melis; Canda, Ebru; Kagnici, Mehtap; U?ar, Sema Kalkan; ?oker, Mahmut

    2017-01-01

    In treatment of metabolic imbalances caused by maple syrup urine disease (MSUD), peritoneal dialysis, and hemofiltration, pharmacological treatments for elimination of toxic metabolites can be used in addition to basic dietary modifications. Therapy with sodium phenylacetate/benzoate or sodium phenylbutyrate (NaPB) in urea-cycle disorder cases has been associated with a reduction in branched-chain amino acid (BCAA) concentrations when the patients are on adequate dietary protein intake. Moreo...

  2. Sodium to sodium carbonate conversion process

    Science.gov (United States)

    Herrmann, Steven D.

    1997-01-01

    A method of converting radioactive alkali metal into a low level disposable solid waste material. The radioactive alkali metal is atomized and introduced into an aqueous caustic solution having caustic present in the range of from about 20 wt % to about 70 wt % to convert the radioactive alkali metal to a radioactive alkali metal hydroxide. The aqueous caustic containing radioactive alkali metal hydroxide and CO.sub.2 are introduced into a thin film evaporator with the CO.sub.2 present in an amount greater than required to convert the alkali metal hydroxide to a radioactive alkali metal carbonate, and thereafter the radioactive alkali metal carbonate is separated from the thin film evaporator as a dry powder. Hydroxide solutions containing toxic metal hydroxide including one or more metal ions of Sb, As, Ba, Be, Cd, Cr, Pb, Hg, Ni, Se, Ag and T1 can be converted into a low level non-hazardous waste using the thin film evaporator of the invention.

  3. The hydrolysis of C12 primary alkyl sulfates in concentrated aqueous solutions. Part 2. Influence of alkyl structure on hydrolytic reactivity in concentrated aqueous mixtures of sodium primary alkyl sulfates : 1-benzoyl-3-phenyl-1,2,4-triazole as a probe o

    NARCIS (Netherlands)

    Bethell, Donald; Fessey, Roger E.; Engberts, Jan B.F.N.; Roberts, David W.

    2001-01-01

    The kinetics of the hydrolysis of aqueous solutions of three sodium C12-alkyl sulfates (SXS), sodium 2-methylundecyl sulfate (SMS), sodium cycloundecylmethyl sulfate (SCS) and sodium 2-pentylheptyl sulfate (SPS), has been investigated at concentrations up to 70% and compared with the behaviour of

  4. Effect of Sodium Chloride Concentrations and Its Foliar Application Time on Quantitative and Qualitative Characteristics of Pomegranate Fruit (Punica granatum L. CV. “Malas Saveh”

    Directory of Open Access Journals (Sweden)

    V. Rouhi

    2016-02-01

    Full Text Available Introduction: Pomegranate (Punica granatum L. belong to Punicaceae family is native to Iran and grown extensively in arid and semi-arid regions worldwide. Pomegranate is also important in human medicine and its components have a wide range of clinical applications. Cracking causes a major fruit loss, which is a serious commercial loss to farmers. Fruit cracking, seems to be a problem that lessens the marketability to a great extent. Fruit cracking is one of the physiological disorders wherever pomegranate trees are grown. It may be due to moisture imbalances as this fruit is very sensitive to variation in soil moisture prolonged drought causes hardening of skin and if this is followed by heavy irrigation the pulp grows then skin grows and cracks. Many factors i.e., climate, soil and irrigation, varieties, pruning, insects and nutrition statues influence the growth and production of fruit trees. Deficiencies of various nutrients are related to soil types, plants and even to various cultivars. Most nutrients are readily fixed in soil having different PH. Plant roots are unable to absorb these nutrients adequately from the dry topsoil. Foliar fertilization is particularly useful under conditions where the absorption of nutrients through the soil and this difficult situation to be present in the nutrients such as calcium. Since the calcium element is needed, so spraying them at the right time is correct way to save the plant requirements. Therefore, a research conducted on effect of sodium chloride concentrations and its foliar application time on quantitative and qualitative characteristics of pomegranate fruit (Punica granatum L. CV. “Malas Saveh”. Materials and Methods: An experiment conducted at Jarghoyeh, Esfahan, Iran in 2012. The factors were Sodium chloride (0, 5 and 10 g/L and times of spray (15, 45 and 75 days before harvest. The study was factorial experiment in the base of randomized complete blocks design with three replications

  5. Lowering Plasma Glucose Concentration by Inhibiting Renal Sodium-Glucose Co-Transport

    Science.gov (United States)

    Abdul-Ghani, Muhammad A; DeFronzo, Ralph A

    2017-01-01

    Maintaining normoglycaemia not only reduces the risk of diabetic microvascular complications but also corrects the metabolic abnormalities that contribute to the development and progression of hyperglycaemia (i.e. insulin resistance and beta-cell dysfunction). Progressive beta-cell failure, in addition to the multiple side effects associated with many current antihyperglycaemic agents (e.g., hypoglycaemia and weight gain) presents major obstacle to the achievement of the recommended goal of glycaemic control in patients with diabetes mellitus (DM). Thus, novel effective therapies are needed for optimal glucose control in subjects with DM. Recently, specific inhibitors of renal sodium glucose cotransporter 2 (SGLT2) have been developed to produce glucosuria and lower the plasma glucose concentration. Because of their unique mechanism of action (which is independent of the secretion and action of insulin), these agents are effective in lowering the plasma glucose concentration in all stages of DM and can be combined with all other antidiabetic agents. In this review, we summarize the available data concerning the mechanism of action, efficacy and safety of this novel class of antidiabetic agent. PMID:24690096

  6. Deficiency of Carbonic Anhydrase II Results in a Urinary Concentrating Defect

    DEFF Research Database (Denmark)

    Krishnan, Devishree; Pan, Wanling; Beggs, Megan R

    2018-01-01

    (TDL); however, the physiological role of a CAII-AQP1 interaction in this nephron segment is not known. To determine if CAII was required for urinary concentration, we studied water handling in CAII-deficient mice. CAII-deficient mice demonstrate polyuria and polydipsia as well as an alkaline urine...... and bicarbonaturia, consistent with a type III renal tubular acidosis. Natriuresis and hypercalciuria cause polyuria, however, CAII-deficient mice did not have increased urinary sodium nor calcium excretion. Further examination revealed dilute urine in the CAII-deficient mice. Urinary concentration remained reduced...

  7. Detection Test for Leakage of CO{sub 2} into Sodium Loop

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sun Hee; Wi, Myung-Hwan; Min, Jae Hong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    This report is about the facility for the detection test for leakage of CO{sub 2} into sodium loop. The facility for the detection test for leakage of CO{sub 2} into sodium loop was introduced. The test will be carried out. Our experimental results are going to be expected to be used for approach methods to detect CO{sub 2} leaking into sodium in heat exchangers. A sodium-and-carbon dioxide (Na-CO{sub 2}) heat exchanger is one of the key components for the supercritical CO{sub 2} Brayton cycle power conversion system of sodium-cooled fast reactors (SFRs). A printed circuit heat exchanger (PCHE) is considered for the Na-CO{sub 2} heat exchanger, which is known to have potential for reducing the volume occupied by the exchangers compared to traditional shell-and-tube heat exchangers. Among various issues about the Na- CO{sub 2} exchanger, detection of CO{sub 2} leaking into sodium in the heat exchanger is most important thing for its safe operation. It is known that reaction products from sodium and CO{sub 2} such as sodium carbonate (Na{sub 2}CO{sub 3}) and amorphous carbon are hardly soluble in sodium, which cause plug sodium channels. Detection technique for Na{sub 2}CO{sub 3} in sodium loop has not been developed yet. Therefore, detection of CO{sub 2} and CO from reaction of sodium and CO{sub 2} are proper to detect CO{sub 2} leakage into sodium loop.

  8. Tissue concentration-time profile of selenium after sodium selenite administration to rats

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, Megumi; Natsuhori, Masahiro; Ito, Nobuhiko [Department of Veterinary Radiology and Radiation Biology, Kitasato University School of Veterinary Medicine, Towada, Aomori (Japan); Sera, Koichiro [Cyclotron Research Center, Iwate Medical University, Takizuka, Iwate (Japan); Futatsugawa, Shoji [Nishina Memorial Cyclotron Center (NMCC), Takizuka, Iwate (Japan)

    1999-07-01

    Selenium (Se) concentration-time profiles in plasma and organs including liver, kidney, heart, lung, spleen and brain of rats (Jcl Wister, 9 wks old, n=32) were investigated after a single intravenous (iv) / oral (po) administration of sodium selenite (dose is equivalent to 2 mg/kg b.w. of Se). The Se concentration was determined by PIXE analysis. Among the investigated biological samples, Se concentration was the highest in the kidney or liver, followed by the heart, lung or spleen, then plasma, and the brain. Se concentrations in these organs were 0.5 to 5 times of plasma Se. The distribution profiles of Se in the organs were dependent on the route of administration. Furthermore, their profiles appeared almost parallel to the plasma Se-concentration in a logarithmic scale. Compared to the Se concentration-time profiles in plasma and organs by the route of administration, po group showed about 1/4-1/2 of the Se concentration in iv group except for kidney. Kidney kept relatively higher concentration of Se, which was similar in the both groups. This may explain our recently published data that urinary excretion was similar in the both groups. The relative oral bioavailability of plasma and each organ was calculated by the ratio of area under the concentration-time curve after oral administration (AUCpo) to AUCiv. Each organ appeared to have their own bioavailability (i.e., liver 39%, kidney 97%, heart 37%, lung 18%, spleen 10%, and brain 72%), where plasma was 46%. These results highly suggested that different Se distribution in organs by the different route of administration was due to the different metabolic profile. (author)

  9. Tissue concentration-time profile of selenium after sodium selenite administration to rats

    International Nuclear Information System (INIS)

    Kaneko, Megumi; Natsuhori, Masahiro; Ito, Nobuhiko; Sera, Koichiro; Futatsugawa, Shoji

    1999-01-01

    Selenium (Se) concentration-time profiles in plasma and organs including liver, kidney, heart, lung, spleen and brain of rats (Jcl Wister, 9 wks old, n=32) were investigated after a single intravenous (iv) / oral (po) administration of sodium selenite (dose is equivalent to 2 mg/kg b.w. of Se). The Se concentration was determined by PIXE analysis. Among the investigated biological samples, Se concentration was the highest in the kidney or liver, followed by the heart, lung or spleen, then plasma, and the brain. Se concentrations in these organs were 0.5 to 5 times of plasma Se. The distribution profiles of Se in the organs were dependent on the route of administration. Furthermore, their profiles appeared almost parallel to the plasma Se-concentration in a logarithmic scale. Compared to the Se concentration-time profiles in plasma and organs by the route of administration, po group showed about 1/4-1/2 of the Se concentration in iv group except for kidney. Kidney kept relatively higher concentration of Se, which was similar in the both groups. This may explain our recently published data that urinary excretion was similar in the both groups. The relative oral bioavailability of plasma and each organ was calculated by the ratio of area under the concentration-time curve after oral administration (AUCpo) to AUCiv. Each organ appeared to have their own bioavailability (i.e., liver 39%, kidney 97%, heart 37%, lung 18%, spleen 10%, and brain 72%), where plasma was 46%. These results highly suggested that different Se distribution in organs by the different route of administration was due to the different metabolic profile. (author)

  10. Fractional ablative carbon dioxide laser followed by topical sodium stibogluconate application: A treatment option for pediatric cutaneous leishmaniasis.

    Science.gov (United States)

    Hilerowicz, Yuval; Koren, Amir; Mashiah, Jacob; Katz, Oren; Sprecher, Eli; Artzi, Ofir

    2018-05-01

    Leishmaniasis is a protozoan zoonotic parasitic infection with cutaneous, mucocutaneous, and visceral manifestations. Israel is endemic for cutaneous leishmaniasis, which is a self-limited disease but is associated with scarring, which is often a source of psychological and social burden for patients. Scars can be especially devastating for children and teenagers. A wide range of physical and medical approaches is used to treat cutaneous leishmaniasis, among which intralesional injections of sodium stibogluconate rank among the most frequently used. Unfortunately, despite being effective, this therapeutic modality can be very painful. Fractional ablative laser creates a controlled mesh-like pattern of tissue ablation in the skin that promotes dermal remodeling and collagen production while at the same time facilitating enhanced delivery of topically applied medications. Patients were treated with fractional ablative carbon dioxide laser followed by immediate topical application of sodium stibogluconate. All children were diagnosed with cutaneous leishmaniasis prior to treatment initiation.. Ten children were treated. One leishmania tropica-positive girl failed to respond. The other nine patients achieved clinical cure and demonstrated good to excellent final cosmesis. Self-rated patient satisfaction and tolerance were high No adverse effects were observed or reported during treatment. Fractional ablative carbon dioxide laser followed by topical sodium stibogluconate application appears to be a safe and promising treatment for cutaneous leishmaniasis infection in children. Future controlled studies are required to validate these findings and compare this technique with traditional approaches. © 2018 Wiley Periodicals, Inc.

  11. 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)

  12. Adsorptivity of uranium by aluminium-activated carbon composite adsorbent

    International Nuclear Information System (INIS)

    Katoh, Shunsaku; Sugasaka, Kazuhiko; Fujii, Ayako; Takagi, Norio; Miyai, Yoshitaka

    1976-01-01

    To research the adsorption process of uranium from sea water by aluminium-activated carbon composite adsorbent (C-Al-OH), the authors examined the effects of temperature, pH and carbonate ion concentration of the solution upon the adsorption of uranium, using sodium chloride solution and natural sea water. The continued mixing of the solution for the duration of two to four hours was required to attain the apparent equilibrium of adsorption. The adsorption velocity at an early stage and the uptake of uranium at the final stage showed an increase in proportion to a rise in the adsorption temperature. In the experiment of adsorption for which sodium chloride solution was used, the linear relationship between the logarithm of the distribution coefficient (K sub(d)) and the pH of the solution was recognized. The uptake of the uranium from the solution at the pH of 12 increased as the carbonate ion concentration in the solution decreased. The uranyl ion in the natural sea water was assumed to be uranyl carbonate complex ion (UO 2 (CO 3 ) 3 4- ). As the result of the calculation conducted by using the formation constants for uranyl complexes in literature, it was found that uranyl hydroxo complex ion (UO 2 (OH) 3 - ) increased in line with a decrease of the carbonate ion concentration in the solution. The above results of the experiment suggested that the adsorption of uranium by the adsorbent (C-Al-OH) was cationic adsorption or hydrolysis adsorption being related with the active proton on the surface of the adsorbent. (auth.)

  13. 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)

  14. Removal of Uranium and Associated Contaminants from Aqueous Solutions Using Functional Carbon Nanotubes-Sodium Alginate Conjugates

    Directory of Open Access Journals (Sweden)

    Hussein Allaboun

    2016-02-01

    Full Text Available Synthesis of hydrophilic/hydrophobic beads from functional carbon nanotubes (CNTs conjugated with sodium alginate was investigated. Glutaraldehyde was used as a coupling agent and Ca2+ as a crosslinking agent. The formed conjugate comprises two-dimensional sheets of sodium alginate bounded to long tufts of functional CNT tails of micro-size geometry. Detailed characterization of the conjugates was performed using thermogravimetric analysis (TGA and its first derivative (DTG, Fourier transform infrared (FTIR, and scanning electron microscope (SEM techniques. Different ratios of the conjugate were successfully prepared and used as biodegradable environmentally friendly sorbents. Removal of U6+, V3+, Cr3+, Mo3+, Pb2+, Mn2+, Cu2+, Ti4+ and Ni2+ from aqueous solutions using the synthesized biosorbent was experimentally demonstrated. Maximum metal uptake of 53 mg/g was achieved using the % Functional CNTs = 33 sample.

  15. Simultaneous and rapid determination of multiple component concentrations in a Kraft liquor process stream

    Science.gov (United States)

    Li, Jian [Marietta, GA; Chai, Xin Sheng [Atlanta, GA; Zhu, Junyoung [Marietta, GA

    2008-06-24

    The present invention is a rapid method of determining the concentration of the major components in a chemical stream. The present invention is also a simple, low cost, device of determining the in-situ concentration of the major components in a chemical stream. In particular, the present invention provides a useful method for simultaneously determining the concentrations of sodium hydroxide, sodium sulfide and sodium carbonate in aqueous kraft pulping liquors through use of an attenuated total reflectance (ATR) tunnel flow cell or optical probe capable of producing a ultraviolet absorbency spectrum over a wavelength of 190 to 300 nm. In addition, the present invention eliminates the need for manual sampling and dilution previously required to generate analyzable samples. The inventive method can be used in Kraft pulping operations to control white liquor causticizing efficiency, sulfate reduction efficiency in green liquor, oxidation efficiency for oxidized white liquor and the active and effective alkali charge to kraft pulping operations.

  16. Concentration of a sodium nitrate-based waste with a wiped film evaporation

    International Nuclear Information System (INIS)

    Farr, L.L.; Boring, M.D.; Fowler, V.L.; Hewitt, J.D.

    1995-01-01

    Oak Ridge National Laboratory (ORNL) currently has an inventory of 500,000 gallons of sodium nitrate-based radioactive liquid waste which is currently stored in the Melton Valley Storage Tanks (MVST). This waste needs to be treated and one option being considered is concentration of the wastes using evaporation. Testing is underway to determine whether a Wiped Film Evaporator (WFE) can be used to concentrate these wastes in an economical and reliable manner. The capability of the evaporator to process a non-radioactive simulant of the MVST wastes over a range of operating conditions is being studied. The equipment has to be checked for reliability, potential corrosion problems, and the effects of the waste on the efficiency of heat transfer due to scaling. Physical and chemical characteristics of the product and distillate are being investigated. Heat transfer coefficients and volume reductions are being determined under different operating conditions. Decontamination factors are being calculated to determine the necessity for further treatment of the distillate and off-gas

  17. High-resolution carbon dioxide concentration record 650,000-800,000 years before present

    DEFF Research Database (Denmark)

    Lüthi, Dieter; Le Floch, Martine; Bereiter, Bernhard

    2008-01-01

    Changes in past atmospheric carbon dioxide concentrations can be determined by measuring the composition of air trapped in ice cores from Antarctica. So far, the Antarctic Vostok and EPICA Dome C ice cores have provided a composite record of atmospheric carbon dioxide levels over the past 650......,000 years. Here we present results of the lowest 200 m of the Dome C ice core, extending the record of atmospheric carbon dioxide concentration by two complete glacial cycles to 800,000 yr before present. From previously published data and the present work, we find that atmospheric carbon dioxide...... is strongly correlated with Antarctic temperature throughout eight glacial cycles but with significantly lower concentrations between 650,000 and 750,000 yr before present. Carbon dioxide levels are below 180 parts per million by volume (p.p.m.v.) for a period of 3,000 yr during Marine Isotope Stage 16...

  18. Effect of oxide ion concentration on the electrochemical oxidation of carbon in molten LiCl

    International Nuclear Information System (INIS)

    Yun, J. W.; Choi, I. K.; Park, Y. S.; Kim, W. H.

    2001-01-01

    The continuous measurement of lithium oxide concentration was required in DOR (Direct Oxide Reduction) process, which converts spent nuclear fuel to metal form, for the reactivity monitor and effective control of the process. The concentration of lithium oxide was measured by the electrochemical method, which was based on the phenomenon that carbon atoms of glassy carbon electrode electrochemically react with oxygen ions of lithium oxide in molten LiCl medium. From the results of electrode polarization experiments, the trend of oxidation rate of carbon atoms was classified into two different regions, which were proportional and non-proportional ones, dependent on the amount of lithium oxide. Below about 2.5 wt % Li 2 O, as the carbon atom ionization rate was fast enough for reacting with diffusing lithium oxide to the surface of carbon electrode. In this concentration range, the oxidation rate of carbon atoms was controlled by the diffusion of lithium oxide, and the concentration of lithium oxide could be measured by electrochemical method. But, above 2.5 wt % Li 2 O, the oxidation rate of carbon atoms was controlled by the applied electrochemical potential, because the carbon atom ionization rate was suppressed by the huge amounts of diffusing Li 2 O. Above this concentration, the electrochemical method was not applicable to determine the concentration of lithium oxide

  19. Antimicrobial Activity of Single-Walled Carbon Nano tubes Suspended in Different Surfactants

    International Nuclear Information System (INIS)

    Dong, L.; Alex Henderson, A.; Field, Ch.

    2012-01-01

    We investigated the antibacterial activity of single-walled carbon nano tubes (SWCNTs) dispersed in surfactant solutions of sodium cholate, sodium dodecylbenzene sulfonate, and sodium dodecyl sulfate. Among the three surfactants, sodium cholate demonstrated the weakest antibacterial activity against Salmonella enterica, Escherichia coli, and Enterococcus faecium and thereby was used to disperse bundled SWCNTs in order to study nano tube antibiotic activity. SWCNTs exhibited antibacterial characteristics for both S. enterica and E. coli. With the increase of nano tube concentrations from 0.3 mg/mL to 1.5 mg/mL, the growth curves had plateaus at lower absorbance values whereas the absorbance value was not obviously affected by the incubation ranging from 5?min to 2 h. Our findings indicate that carbon nano tubes could become an effective alternative to antibiotics in dealing with drug-resistant and multidrug-resistant bacterial strains because of the physical mode of bactericidal action that SWCNTs display

  20. Synthesis of high luminescent carbon nanoparticles

    Science.gov (United States)

    Gvozdyuk, Alina A.; Petrova, Polina S.; Goryacheva, Irina Y.; Sukhorukov, Gleb B.

    2017-03-01

    In this article we report an effective and simple method for synthesis of high luminescent carbon nanodots (CDs). In our work as a carbon source sodium dextran sulfate (DS) was used because it is harmless, its analogs are used in medicine as antithrombotic compounds and blood substitutes after hemorrhage. was used as a substrate We investigated the influence of temperature parameters of hydrothermal synthesis on the photoluminescence (PL) intensity and position of emission maxima. We discovered that the PL intensity can be tuned by changing of synthesis temperature and CD concentration.

  1. Stable carbon and nitrogen isotope ratios of sodium and potassium cyanide as a forensic signature.

    Science.gov (United States)

    Kreuzer, Helen W; Horita, Juske; Moran, James J; Tomkins, Bruce A; Janszen, Derek B; Carman, April

    2012-01-01

    Sodium and potassium cyanide are highly toxic, produced in large amounts by the chemical industry, and linked to numerous high-profile crimes. The U.S. Centers for Disease Control and Prevention has identified cyanide as one of the most probable agents to be used in a chemical terrorism event. We investigated whether stable C and N isotopic content of sodium and potassium cyanide could serve as a forensic signature for sample matching, using a collection of 65 cyanide samples. Upon analysis, a few of the cyanide samples displayed nonhomogeneous isotopic content associated with degradation to a carbonate salt and loss of hydrogen cyanide. Most samples had highly reproducible isotope content. Of the 65 cyanide samples, >95% could be properly matched based on C and N isotope ratios, with a false match rate <3%. These results suggest that stable C and N isotope ratios are a useful forensic signature for matching cyanide samples. © 2011 American Academy of Forensic Sciences.

  2. Purification and characterization of smectite clay taken from Gafsa, Tunisia: Progressive elimination of carbonates

    International Nuclear Information System (INIS)

    Mhamdi, M; Gasmi, N; Elaloui, E; Kbir-Ariguib, N; Trabelsi-Ayadi, M

    2010-01-01

    This work shows the results of various analysis on a representative clay sample from southern west of Tunisia, particularly from Oued Tfal near the town of Gafsa. The raw smectite contains some carbonate, quartz, chlorite, and anorthite. During the attack of the carbonate clay with a solution of hydrochloric acid, a change of the chemical composition and physical properties was observed. This change is dependent on several factors: the initial concentration of the acid, the nature of the clay, the ratio acid / clay...). Although treatment to 0.5 M represents a total removal of carbonates, there are probably altered layers of the clay fraction. The result shows that for a treatment with acid solutions of concentrations below 0.5 M there is gradual removal of carbonate without protonation of the clay layers. The characterization of the clay fraction shows that the sodium clay purified (OTNa) consists of a sodium montmorillonite smectite. The cation exchange capacity and the specific surface of OTNa measured using the method of methylene blue are equal to 82 meq/100g and 667 m 2 / g respectively.

  3. Effect of carbonic anhydrase on silicate weathering and carbonate formation at present day CO2 concentrations compared to primordial values

    Science.gov (United States)

    Xiao, Leilei; Lian, Bin; Hao, Jianchao; Liu, Congqiang; Wang, Shijie

    2015-01-01

    It is widely recognized that carbonic anhydrase (CA) participates in silicate weathering and carbonate formation. Nevertheless, it is still not known if the magnitude of the effect produced by CA on surface rock evolution changes or not. In this work, CA gene expression from Bacillus mucilaginosus and the effects of recombination protein on wollastonite dissolution and carbonate formation under different conditions are explored. Real-time fluorescent quantitative PCR was used to explore the correlation between CA gene expression and sufficiency or deficiency in calcium and CO2 concentration. The results show that the expression of CA genes is negatively correlated with both CO2 concentration and ease of obtaining soluble calcium. A pure form of the protein of interest (CA) is obtained by cloning, heterologous expression, and purification. The results from tests of the recombination protein on wollastonite dissolution and carbonate formation at different levels of CO2 concentration show that the magnitudes of the effects of CA and CO2 concentration are negatively correlated. These results suggest that the effects of microbial CA in relation to silicate weathering and carbonate formation may have increased importance at the modern atmospheric CO2 concentration compared to 3 billion years ago. PMID:25583135

  4. Study of new complexes of uranium and comba radical. I.- Complexes defective in sodium carbonate; Estudio de nuevos complejos entre el uranio y el radical CDMBA. I. Complejos con defectos de carbonato sodico

    Energy Technology Data Exchange (ETDEWEB)

    Vera Palomino, J; Galiano Sedano, J A; Parellada Bellod, R; Bellido Gonzalez, A

    1975-07-01

    Some complexes formed in presence of defect of sodium carbonate with respect to the stoichiometric ratio (U): (C0{sub 3}) = 1:3 are studied. This ratio corresponds to the main complex which is responsible for the uranium extraction with CDMBAC organic solutions and from U(VI) aqueous solutions with an excess of sodium carbonate. (Author) 10 refs.

  5. Carbonic acid salts at 25 or 45 degrees C to control loquat decay under shelf life conditions.

    Science.gov (United States)

    Molinu, M G; D'Hallewin, G; Dore, A; Serusi, A; Venditti, T; Agabbio, M

    2005-01-01

    Generally recognised as save compounds (G.R.A.S) are attractive substitutes to synthetic chemicals in postharvest control diseases. They meet safety requirements, are cheap and able to be integrated with other disease control technologies. Among G.R.A.S compounds, carbonic acid salts have been investigated on carrots, bell pepper, melons, sweet cherries and their efficacy was also evaluated when combined with biological control agents. Moreover, the possibility to use sodium carbonate and sodium bicarbonate to prevent P. digitatum an P. italicum spread on Citrus fruit was studied since the begin of the 20th century. We explored the possibility to extend the use of carbonate-bicarbonate salts on loquat fruit in order to control the pathogens and to extend postharvest life. Loquat is a very perishable fruit, susceptible to decay, mechanical damage, moisture and nutritional losses during its postharvest life. We tested the combined effect of temperature and sodium or potassium carbonate-bicarbonate and ammonium carbonate. The fruit was dipped in the salt solutions at variable concentrations (0.5, 1 and 2% w/v) at 25 or 45 degrees C for two minutes and than stored under shelf life conditions (25 degrees C and 70% RH). Decay, weight loss, pH, titrable acidity and sugar content were detected after twelve days. Preliminary data show that the combined treatments were effective in decay control depending on salts. Best results were obtained with 2% potassium and sodium carbonate solution at 25 degrees C. Weight losses were related to treatment temperature and salts concentrations whereas, no differences were detected in the chemical parameters compared to the control.

  6. Evaluation of the potential of additives as corrosion inhibitors of CA-50 carbon steel used as reinforcement in concretes

    International Nuclear Information System (INIS)

    Mennucci, Marina Martins

    2006-01-01

    In this work, various compounds were tested to evaluate their potential capability for their use as corrosion inhibitors of carbon steel reinforcement in concretes. The additives tested were sodium benzoate, polyethylene glycol, hexamethylenetetramine, benzotriazole and yttrium carbonate. Initially, exploratory tests were carried out to select the ones to be used as corrosion inhibitors, based on the inhibit ion efficiency determined from electrochemical tests, specifically polarization tests and electrochemical impedance spectroscopy. These tests were carried out in a solution composed of 0.01 N sodium hydroxide (NaOH) and 0.05 N potassium hydroxide (KOH) to simulate the composition of the solution inside the pores in concretes. The additive that presented the most promising potential to be used as corrosion inhibitor was benzotriazole (BTA). After the elimination of some compounds and selection of the additive with higher corrosion inhibit ion efficiency in the test medium, the effect of its concentration on the corrosion inhibition efficiency was evaluated. Sodium nitrite solutions with the same concentrations as those solutions with BTA were tested for comparison reasons. Sodium nitrite is a well established corrosion inhibitor for carbon steel reinforcement in concretes but it has been related to toxic effects. The BTA was associated to higher corrosion inhibition efficiencies than that of sodium nitrite in similar concentrations. A blackish adherent film was formed on the steel surface exposed to BTA solutions during long periods of immersion in the alkaline medium. The results suggest that BTA is a potential candidate for substitution of nitrites as corrosion inhibitor of reinforcements in concrete. (author)

  7. Effect of sodium carbonate solution on self-setting properties of tricalcium silicate bone cement.

    Science.gov (United States)

    Zhiguang Huan; Jiang Chang

    2008-11-01

    In this study, the effects of sodium carbonate (Na(2)CO(3) ) solution with different concentrations (10, 15, 20, and 25 wt%) as liquid phase on the setting time and compressive strength of tricalcium silicate bone cements are investigated. The in vitro bioactivity and degradability of the resultant Ca(3)SiO(5)-Na(2)CO(3) solution paste was also studied. The results indicate that as the concentration of Na(2)CO(3) solution varies from 0 to 25 wt%, the initial and final setting time of the cement decrease significantly from 90 to 20 min and from 180 to 45 min, respectively. After setting for 24 h, the compressive strength of Ca(3)SiO(5)-Na(2)CO(3) solution paste reaches 5.1 MPa, which is significantly higher than that of Ca( 3)SiO(5)-water cement system. The in vitro bioactivity of the cements is investigated by soaking in simulated body fluid (SBF) for 7 days. The results show that the Ca(3)SiO(5)-Na(2)CO( 3) solution bone cement has a good bioactivity and can degrade in Ringer's solution. The results indicate that Na(2)CO(3) solution as a liquid phase significantly improves the self-setting properties of Ca( 3)SiO(5) cement as compared to water. The Ca(3)SiO( 5) cement paste prepared using Na(2)CO(3) solution shows good bioactivity and moderate degradability, and the Ca(3)SiO( 5)-Na(2)CO(3) solution system may be used as degradable and bioactive bone defect filling materials.

  8. Sodium aerosol recovering device

    International Nuclear Information System (INIS)

    Fujimori, Koji; Ueda, Mitsuo; Tanaka, Kazuhisa.

    1997-01-01

    A main body of a recovering device is disposed in a sodium cooled reactor or a sodium cooled test device. Air containing sodium aerosol is sucked into the main body of the recovering device by a recycling fan and introduced to a multi-staged metal mesh filter portion. The air about against each of the metal mesh filters, and the sodium aerosol in the air is collected. The air having a reduced sodium aerosol concentration circulates passing through a recycling fan and pipelines to form a circulation air streams. Sodium aerosol deposited on each of the metal mesh filters is scraped off periodically by a scraper driving device to prevent clogging of each of the metal filters. (I.N.)

  9. Effect of a passive sonic irrigation system on elimination of Enterococcus faecalis from root canal systems of primary teeth, using different concentrations of sodium hypochlorite: An in vitro evaluation

    Directory of Open Access Journals (Sweden)

    Elham Afshari

    2017-09-01

    Full Text Available Background. This in vitro study aimed to compare the antibacterial effect of different concentrations of sodium hypochlorite on elimination of Enterococcus faecalis from root canal systems of primary teeth with or without a passive sonic irrigation system (EndoActivator. Methods. The root canals of 120 extracted single-rooted primary incisors were prepared using the crown-down technique. The teeth were autoclaved and inoculated with E. faecalis. The infected samples were then randomly divided into 6 experimental groups of 15 and positive and negative control groups as follows: group 1: 0.5% sodium hypochlorite solution; group 2: 2.5% sodium hypochlorite solution; group 3: 5% sodium hypochlorite solution; group 4: 0.5% sodium hypochlorite solution + sonic activation; group 5: 2.5% sodium hypochlorite solution + sonic activation; and group 6: 5% sodium hypochlorite solution + sonic activation. Microbiological samples were collected before and after disinfection procedures and the colony-forming units were counted. Statistical analyses were performed using the two-way ANOVA and post hoc Duncan's tests in cases of significant difference. Results. There were no significant differences between the groups in any of the variables (concentration of antiseptic or use of sonic irrigation system. Conclusion. Use of passive sonic irrigation systems in endodontic treatment of single-rooted primary teeth is of no benefit compared to regular needle irrigation. The results of this study also recommends use of lower concentrations of sodium hypochlorite solution (0.5% for irrigation of the root canal system rather than higher concentrations given approximately equal efficacy.

  10. Comparison of manufactured and black carbon nanoparticle concentrations in aquatic sediments

    NARCIS (Netherlands)

    Koelmans, A.A.; Nowack, B.; Wiesner, M.

    2009-01-01

    In this paper, we show that concentrations of manufactured carbon-based nanoparticles (MCNPs) in aquatic sediments will be negligible compared to levels of black carbon nanoparticles (BCNPs). This is concluded from model calculations accounting for MCNP sedimentation fluxes, removal rates due to

  11. How low can you go? Assessing minimum concentrations of NSC in carbon limited tree saplings

    Science.gov (United States)

    Hoch, Guenter; Hartmann, Henrik; Schwendener, Andrea

    2016-04-01

    Tissue concentrations of non-structural carbohydrates (NSC) are frequently used to determine the carbon balance of plants. Over the last years, an increasing number of studies have inferred carbon starvation in trees under environmental stress like drought from low tissue NSC concentrations. However, such inferences are limited by the fact that minimum concentrations of NSC required for survival are not known. So far, it was hypothesized that even under lethal carbon starvation, starch and low molecular sugar concentrations cannot be completely depleted and that minimum NSC concentrations at death vary across tissues and species. Here we present results of an experiment that aimed to determine minimum NSC concentrations in different tissues of saplings of two broad-leaved tree species (Acer pseudoplatanus and Quercus petratea) exposed to lethal carbon starvation via continuous darkening. In addition, we investigated recovery rates of NSC concentrations in saplings that had been darkened for different periods of time and were then re-exposed to light. Both species survived continuous darkening for about 12 weeks (confirmed by testing the ability to re-sprout after darkness). In all investigated tissues, starch concentrations declined close to zero within three to six weeks of darkness. Low molecular sugars also decreased strongly within the first weeks of darkness, but seemed to stabilize at low concentrations of 0.5 to 2 % dry matter (depending on tissue and species) almost until death. NSC concentrations recovered surprisingly fast in saplings that were re-exposed to light. After 3 weeks of continuous darkness, tissue NSC concentrations recovered within 6 weeks to levels of unshaded control saplings in all tissues and in both species. To our knowledge, this study represents the first experimental attempt to quantify minimum tissue NSC concentrations at lethal carbon starvation. Most importantly, our results suggest that carbon-starved tree saplings are able to

  12. Synthesis and electrochemical probing of water-soluble poly(sodium 4-styrenesulfonate-co-acrylic acid)-grafted multiwalled carbon nanotubes

    International Nuclear Information System (INIS)

    Du Feipeng; Yang Yingkui; Xie Xiaolin; Wu Kangbing; Gan Tian; Liu Lang

    2008-01-01

    Water-soluble poly(sodium 4-styrenesulfonate-co-acrylic acid)-grafted multiwalled carbon nanotubes (MWNT-g-P(SSS-co-AA)) with core-shell nanostructure were successfully synthesized by in situ free radical copolymerization of sodium 4-strenesulfonate (SSS) and acrylic acid (AA) in the presence of MWNTs terminated with vinyl groups; their structure was characterized by FTIR, 1 H NMR, Raman, TGA and TEM. The results showed that the thickness and content of the copolymer layer grafted onto the MWNT surface are about 7-12 nm and 82.3%, respectively. The P(SSS-co-AA) covalently grafted on MWNTs provides MWNT-g-P(SSS-co-AA) with good hydrophilicity and solubility in water. Then a novel MWNT-g-P(SSS-co-AA)-modified glassy carbon electrode was fabricated by coating; its electrochemical properties were evaluated by electrochemical probe of K 3 [Fe(CN) 6 ], and its catalytic behaviors to the electrochemical oxidation processes of dopamine (DA) and serotonin (5-HT) were investigated. Since the MWNT-g-P(SSS-co-AA)-modified electrode possesses strong electron transfer capability, high electrochemical activity and catalytic ability, it can be used in sensitive, selective, rapid and simultaneous monitoring of biomolecules

  13. Silver birch and climate change: variable growth and carbon allocation responses to elevated concentrations of carbon dioxide and ozone

    International Nuclear Information System (INIS)

    Riikonen, J.; Holopainen, T.; Oksanen, E.; Lindsberg, M-M.; Lappi, J.; Peltonen, P.; Vapaavuori, E.

    2004-01-01

    The effects of elevated concentrations of carbon dioxide and ozone were studied on growth, biomass allocation and leaf area of field-grown ozone-tolerant (Clone 4) and ozone-sensitive (Clone 80) European silver birch trees. Seven-year old trees of both types were exposed for three years to outside and chamber control, (1) twice ambient ozone, (2) twice ambient carbon dioxide, and (3) twice ambient carbon dioxide and twice ambient ozone. No effect on biomass allocation was observed when results of the two clones were analyzed together. Total leaf area showed an increase, and leaf abscission appeared delayed in response to elevated carbon dioxide. Elevated ozone caused the dry mass of roots, branches and mean leaf size to decrease, and autumnal leaf abscission occurred earlier than usual in both clones. In general. the effects of elevated ozone were small, however, the interaction between elevated carbon dioxide and elevated oxygen were significant. When results from the two clones were analyzed separately, stem diameter, volume growth and total biomass of Clone 80 increased when exposed to elevated concentrations of carbon dioxide; elevated concentrations of ozone appeared to have no effect. In Clone 4 elevated ozone caused significant decrease in root and branch biomass, but the effects of elevated carbon dioxide were minimal. Responses to elevated ozone exposure were observed only under ambient carbon dioxide conditions. This response is believed to reflect the greater quantity of carbohydrates available for detoxification and repair under elevated carbon dioxide conditions. Alternatively, the response may be due to decreased stomatal conductance, thus decreased ozone uptake under elevated carbon dioxide conditions. 45 refs., 6 tabs., 4 figs

  14. Carbonic anhydrase (acetazolamide-sensitive esterase) activity in the blood, gill and kidney of the thermally acclimated rainbow trout, Salmo gairdneri

    Energy Technology Data Exchange (ETDEWEB)

    Houston, A.H.; McCarty, L.S.

    1978-04-01

    Gill, kidney and blood levels of acetazolamide-sensitive esterase (carbonic anhydrase) activity were estimated at acclimation temperature and at a common temperature (25/sup 0/C) in rainbow trout acclimated to 2, 10, and 18/sup 0/C. Plasma levels of sodium, potassium and chloride were also examined for possible acclimatory variations. Plasma sodium and chloride levels, and the sodium:chloride ratio were unaffected by thermal acclimation; potassium concentrations were significantly elevated at 18/sup 0/C. Significant, but modest changes in renal and branchial carbonic anhydrase activity were observed under physiologically realistic incubation temperature conditions. Blood carbonic anhydrase activity was sharply elevated at higher acclimation temperatures. The data are discussed in relation to the hypothesis that carbonic anhydrase in this relatively stenothermal freshwater salmonid, through its intimate association with the coupled HCO/sub 3//sup -//Cl/sup -/ and H/sup +/ + NH/sub 4//sup +//Na/sup +/ exchange systems may provide for relatively thermostable basal rates of sodium and chloride uptake from the medium and recovery from urine. The renal, and more notably the branchial (Na/sup +//K/sup +/)-simulated ATPase systems, and erythrocytic carbonic anhydrase may then serve primarily as high-temperature amplifiers of sodium and chloride recruitment respectively.

  15. Concentration of uranium in seawater by flotation

    International Nuclear Information System (INIS)

    Nozaki, Toru; Yamashita, Hiroshi

    1986-01-01

    A method has been developed for the concentration of uranium in seawater by precipitation flotation-carbonate extraction-ion flotation. Uranium in seawater was coprecipitated with hydrated iron (III) oxide by adjusting the pH to 5.5 after addition of 1.0 x 10 -3 mol/l of iron (III) and agitating for 1 hr, and the precipitate was floated with 1.0 x 10 -5 mol/l of sodium oleate and 5.0 x 10 -5 mol/l of sodium lauryl sulfate by bubbling nitrogen through the seawater for 15 min. Uranium was extracted from the precipitate scum at the yield of 89 % with 100 ml of 1.8 % of ammonium carbonate solution by agitating for 2 hr, and floated with 1.2 x 10 -3 mol/l of cetylpyridinium chloride by bubbling nitrogen through the extract diluted 5-fold for 30 min in the recovery of about 100 %. The fairly selective recovery of uranium was obtained from 4 l of seawater at the yield of 87 % throughout the entire process. (author)

  16. Characterization of Sodium Spray Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, C. T.; Koontz, R. L.; Silberberg, M. [Atomics International, North American Rockwell Corporation, Canoga Park, CA (United States)

    1968-12-15

    The consequences of pool and spray fires require evaluation in the safety analysis of liquid metal-cooled fast breeder reactors. Sodium spray fires are characterized by high temperature and pressure, produced during the rapid combustion of sodium in air. Following the initial energy release, some fraction of the reaction products are available as aerosols which follow the normal laws of agglomeration, growth, settling, and plating. An experimental study is underway at Atomics International to study the characteristics of high concentration sprays of liquid sodium in reduced oxygen atmospheres and in air. The experiments are conducted in a 31.5 ft{sup 3} (2 ft diam. by 10 ft high) vessel, certified for a pressure of 100 lb/in{sup 2} (gauge). The spray injection apparatus consists of a heated sodium supply pot and a spray nozzle through which liquid sodium is driven by nitrogen pressure. Spray rate and droplet size can be varied by the injection velocity (nozzle size, nitrogen pressure, and sodium temperature). Aerosols produced in 0, 4, and 10 vol. % oxygen environments have been studied. The concentration and particle size distribution of the material remaining in the air after the spray injection and reaction period are measured. Fallout rates are found to be proportional to the concentration of aerosol which remains airborne following the spray period. (author)

  17. Pitting corrosion of lead in sodium carbonate solutions containing NO3- ions

    International Nuclear Information System (INIS)

    Amin, Mohammed A.; Abdel Rehim, Sayed S.

    2004-01-01

    Pitting corrosion of Pb in Na 2 CO 3 solutions (pH=10.8) containing NaNO 3 as a pitting corrosion agent has been studied using potentiodynamic anodic polarization, cyclic voltammetry and chronoamperometry techniques, complemented with scanning electron microscopy (SEM) examinations of the electrode surface. In the absence of NO 3 - , the anodic voltammetric response exhibits three anodic peaks prior to oxygen evolution. The first anodic peak A 1 corresponds to the formation of PbCO 3 layer and soluble Pb 2+ species in solution. The second anodic peak A 2 is due to the formation of PbO beneath the carbonate layer. Peak A 2 is followed by a wide passive region which extends up to the appearance of the third anodic peak A 3 . The later is related to the formation of PbO 2 . Addition of NO 3 - to the carbonate solution stimulates the anodic dissolution through peaks A 1 and A 2 and breaks down the dual passive layer prior to peak A 3 . The breakdown potential decreases with an increase in nitrate concentration, temperature and electrode rotation rate, but increases with an increase in carbonate concentration and potential scan rate. Successive cycling leads to a progressive increase in breakdown potential. The current/time transients show that the incubation time for passivity breakdown decreases with increasing the applied anodic potential, nitrate concentration and temperature

  18. Nonlinear optical properties measurement of polypyrrole -carbon nanotubes prepared by an electrochemical polymerization method

    Directory of Open Access Journals (Sweden)

    Shahriari

    2017-02-01

    Full Text Available In this work, the optical properties dependence of Multi-Walled Carbon Nanotubes (MWNT on concentration was discussed. MWNT samples were prepared in polypyrrole by an electrochemical polymerization of monomers, in the presence of different concentrations of MWNTs, using Sodium Dodecyl-Benzen-Sulfonate (SDBS as surfactant at room temperature. The nonlinear refractive and nonlinear absorbtion indices were measured using a low power CW laser beam operated at 532 nm using z-scan method. The results show that nonlinear refractive and nonlinear absorbtion indices tend to be increased with increasing the concentration of carbon nanotubes. Optical properties of  carbone nanotubes indicate that they are good candidates for nonlinear optical devices

  19. Effects of sodium caseinate concentration and storage conditions on the oxidative stability of oil-in-water emulsions.

    Science.gov (United States)

    O' Dwyer, Sandra P; O' Beirne, David; Eidhin, Deirdre Ní; O' Kennedy, Brendan T

    2013-06-01

    The oxidative stability of various oils (sunflower, camelina and fish) and 20% oil-in-water (O/W) emulsions, were examined. The mean particle size decreased from 1179 to 325 nm as sodium caseinate (emulsifier) concentration was increased from 0.25% to 3% in O/W emulsions (Psodium caseinate concentration increased, and similarly decreased as microfluidisation pressure increased (P<0.05). Increasing storage temperature of the emulsions from 5 to 60°C, resulted in lower detectable lipid oxidation products during storage (P<0.05). Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Carbonic anhydrase levels and internal lacunar CO/sub 2/ concentrations in aquatic macrophytes

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, C.I.

    1979-01-01

    Carbonic anhydrase levels were examined in a variety of aquatic macrophytes from different habitats. In general, carbonic anhydrase levels increased across the habitat gradient such that activities were low in submersed aquatic macrophytes and high in emergent macrophytes with floating-leaved and free-floating plants exhibiting intermediate activities. Internal lacunar CO/sub 2/ concentrations were analyzed in relation to carbonic anhydrase activities. There was no correlation between these two parameters. Internal CO/sub 2/ concentrations ranged from low to high in submersed macrophytes, but were low in floating-leaved and emergent macrophytes. The observed internal CO/sub 2/ concentrations are discussed in relation to the individual morphologies of the plants and the environments in which they occurred.

  1. Study of lithium extraction from brine water, Bledug Kuwu, Indonesia by the precipitation series of oxalic acid and carbonate sodium

    Science.gov (United States)

    Sulistiyono, Eko; Lalasari, Latifa Hanum; Mayangsari, W.; Prasetyo, A. B.

    2018-05-01

    Lithium is one of the key elements in the development of batteries for electric car applications. Currently, the resources of the world's lithium are derived from brine water and lithium mineral based on spodumene rock. Indonesia which is located in the area of the ring of fire, has potential brine water resources in some area, such as brine water from Bledug Kuwu, Central Java that used in this research. The purposes of this research are to characterize brine water, Bledug Kuwu and to investigate the influence of chemical solvents on Li, Na, K, Ca, Mg, Al, B ion precipitation from brine water. This research was done with 2 times the process of chemical precipitation that runs series as follows: 5 liters of brine water were chemically precipitated using 400 ml of 12.43 N oxalic acid and followed by chemical precipitation using 400 mL of 7.07 N sodium carbonate solutions. Evaporation and filtration processes were also done twice in an effort to separate white precipitate and filtrate. The filtrate was analyzed by ICP-OES and white precipitates (salts) were analyzed by SEM, XRD, and XRF. The result shows that oxalate precipitation process extracted 32.24% Al, 23.42% B, 22.43% Ca, 14.26% Fe, 3.21 % K, 9.86% Na and 14.26% Li, the following process by carbonate precipitation process extracted 98.86% Mg, 73% Ca, 22.53% Li, 82.04% Al, 14.38% B, 12.50% K, 2.27% Na. There is 63.21% lithium is not extracted from the series process. The SEM analysis shows that the structure of granules on the precipitated salts by oxalic acid form gentle cubic-shaped solid. In the other hand, oxalate precipitation followed by sodium carbonate has various particle sizes and the shape of crystals is fragments, prism and cube look like magnesium carbonate, calcium chloride, and calcite's crystal respectively. This is in accordance with XRD analysis that phases of whewellite (CaC2O4.H2O), disodium oxalate (Na2C2O4), magnesite (MgCO3), calcium lithium aluminum (Al1.19 Ca1Li0.81), dolomite (CaCO3

  2. Modeling the Combined Effects of Temperature, pH, and Sodium Chloride and Sodium Lactate Concentrations on the Growth Rate of Lactobacillus plantarum ATCC 8014

    Directory of Open Access Journals (Sweden)

    Francieli Dalcanton

    2018-01-01

    Full Text Available Nowadays, microorganisms with probiotic or antimicrobial properties are receiving major attention as alternative resources for food preservation. Lactic acid bacteria are able to synthetize compounds with antimicrobial activity against pathogenic and spoilage flora. Among them, Lactobacillus plantarum ATCC 8014 has exhibited this capacity, and further studies reveal that the microorganism is able to produce bacteriocins. An assessment of the growth of L. plantarum ATCC 8014 at different conditions becomes crucial to predict its development in foods. A response surface model of the growth rate of L. plantarum was built in this study as a function of temperature (4, 7, 10, 13, and 16°C, pH (5.5, 6.0, 6.5, 7.0, and 7.5, and sodium chloride (0, 1.5, 3.0, 4.5, and 6.0% and sodium lactate (0, 1, 2, 3, and 4% concentrations. All the factors were statistically significant at a confidence level of 90%  (p<0.10. When temperature and pH increased, there was a corresponding increase in the growth rate, while a negative relationship was observed between NaCl and Na-lactate concentrations and the growth parameter. A mathematical validation was carried out with additional conditions, demonstrating an excellent performance of the model. The developed model could be useful for designing foods with L. plantarum ATCC 8014 added as a probiotic.

  3. Natural variability in the surface ocean carbonate ion concentration

    OpenAIRE

    N. S. Lovenduski; M. C. Long; K. Lindsay

    2015-01-01

    We investigate variability in the surface ocean carbonate ion concentration ([CO32−]) on the basis of a long control simulation with a fully-coupled Earth System Model. The simulation is run with a prescribed, pre-industrial atmospheric CO2 concentration for 1000 years, permitting investigation of natural [CO32−] variability on interannual to multi-decadal timescales. We find high interannual variability in surface [CO32−] in the tropical...

  4. Natural variability in the surface ocean carbonate ion concentration

    OpenAIRE

    Lovenduski, N. S.; Long, M. C.; Lindsay, K.

    2015-01-01

    We investigate variability in the surface ocean carbonate ion concentration ([CO32−]) on the basis of a~long control simulation with an Earth System Model. The simulation is run with a prescribed, pre-industrial atmospheric CO2 concentration for 1000 years, permitting investigation of natural [CO32−] variability on interannual to multi-decadal timescales. We find high interannual variability in surface [CO32−] in the tropical Pacific and ...

  5. Influence of Concentration and Agitation of Sodium Hypochlorite and Peracetic Acid Solutions on Tissue Dissolution.

    Science.gov (United States)

    Tanomaru-Filho, Mário; Silveira, Bruna Ramos Franco; Martelo, Roberta Bosso; Guerreiro-Tanomaru, Juliane Maria

    2015-11-01

    To evaluated the tissue dissolution of sodium hypochlorite (NaOCl) and peracetic acid (PA) solutions at different concentrations, with or without ultrasonic agitation. The following solutions were analyzed: 2.5% NaOCl, 0.5, 1 and 2% PA, 1% PA associated with 6.5% hydrogen peroxide (HP) and saline. Fragments of bovine pulp tissue with 25 ± 2g mg were immersed into test tubes containing 4 mL of the solutions for 10 minutes. In the groups with agitation, pulp tissues were submitted to 2 cycles of 1 minute of ultrasonic agitation. The specimens were weighed after the removal from the solutions. The percentage of mass loss was calculated according to the difference of mass before and after exposure to solutions. Data were submitted to ANOVA and Tukey tests (p Peracetic acid solution has pulp tissue dissolution. However, this ability is lower than 2.5% NaOCl solution. The sodium hypochlorite solution shows higher ability to dissolve tissue than PA.

  6. Effect of sodium bicarbonate and varying concentrations of sodium chloride in brine on the liquid retention of fish (Pollachius virens L.) muscle.

    Science.gov (United States)

    Åsli, Magnus; Ofstad, Ragni; Böcker, Ulrike; Jessen, Flemming; Einen, Olai; Mørkøre, Turid

    2016-03-15

    Negative health effects associated with excessive sodium (Na) intake have increased the demand for tasty low-Na products (<2% NaCl) rather than traditional heavily salted fish products (∼20% NaCl). This study investigates the causes of improved yield and liquid retention of fish muscle brined with a combination of salt (NaCl) and sodium bicarbonate (NaHCO3 ). Water characteristics and microstructure of saithe (Pollachius virens L.) muscle brined in solutions of NaCl and NaHCO3 or NaCl alone were compared using low-field nuclear magnetic resonance (LF-NMR) T2 relaxometry, microscopy, salt content, liquid retention and colorimetric measurements. Saithe muscle was brined for 92 h in 0, 30, 60, 120 or 240 g kg(-1) NaCl or the respective solutions with added 7.5 g kg(-1) NaHCO3 . NaHCO3 inclusion improved the yield in solutions ranging from 0 to 120 g kg(-1) NaCl, with the most pronounced effect being observed at 30 g kg(-1) NaCl. The changes in yield were reflected in water mobility, with significantly shorter T2 relaxation times in all corresponding brine concentrations. Salt-dependent microstructural changes were revealed by light microscopy, where NaHCO3 supplementation resulted in greater intracellular space at 30 and 60 g kg(-1) NaCl. Sodium bicarbonate addition to low-salt solutions can improve yield and flesh quality of fish muscle owing to altered water mobility and wider space between the muscle cells. © 2015 Society of Chemical Industry.

  7. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    International Nuclear Information System (INIS)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

    2002-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO(sub 2) as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbents being investigated in this project are primarily alkali carbonates, and particularly sodium carbonate and potassium carbonate, which are converted to bicarbonates, through reaction with carbon dioxide and water vapor. Bicarbonates are regenerated to carbonates when heated, producing a nearly pure CO(sub 2) stream after condensation of water vapor. This quarter, electrobalance tests conducted at LSU indicated that exposure of sorbent to water vapor prior to contact with carbonation gas does not significantly increase the reaction rate. Calcined fine mesh trona has a greater initial carbonation rate than calcined sodium bicarbonate, but appears to be more susceptible to loss of reactivity under severe calcination conditions. The Davison attrition indices for Grade 5 sodium bicarbonate, commercial grade sodium carbonate and extra fine granular potassium carbonate were, as tested, outside of the range suitable for entrained bed reactor testing. Fluidized bed testing at RTI indicated that in the initial stages of reaction potassium carbonate removed 35% of the carbon dioxide in simulated flue gas, and is reactive at higher temperatures than sodium carbonate. Removals declined to 6% when 54% of the capacity of the sorbent was exhausted. Carbonation data from electrobalance testing was correlated using a shrinking core reaction model. The activation energy of the reaction of sodium carbonate with carbon dioxide and water vapor was determined from nonisothermal thermogravimetry

  8. Equilibrium concentration of radionuclides in cement/groundwater/carbon steel system

    International Nuclear Information System (INIS)

    Keum, D. K.; Cho, W. J.; Hahn, P. S.

    1997-01-01

    Equilibrium concentration of major elements in an underground repository with a capacity of 100,000 drums have been simulated using the geochemical computer code (EQMOD). The simulation has been carried out at the conditions of pH 12 to 13.5, and Eh 520 and -520 mV. Solubilities of magnesium and calcium decrease with the increase of pH. The solubility of iron increases with pH at Eh -520 mV of reducing environment, while it almost entirely exists as the precipitate of Fe(OH) 3 (s) at Eh 520 mV of oxidizing environment. All of cobalt and nickel are predicted to be dissolved in the liquid phase regardless of pH since the solubility limit is greater than the total concentration. In the case of cesium and strontium, all forms of both ions are present in the liquid phase because they have negligible sorption capacity on cement and large solubility under disposal atmosphere. And thus the total concentration determines the equilibrium concentration. Adsorbed amounts of iodide and carbonate are dependent on adsorption capacity and adsorption equilibrium constant. Especially, the calcite turns out to be a solubility-limiting phase on the carbonate system. In order to validate the model, the equilibrium concentrations measured for a number of systems which consist of iron, cement, synthetic groundwater and radionuclides are compared with those predicted by the model. The concentrations between the model and the experiment of nonadsorptive elements - cesium, strontium, cobalt, nickel and iron, are well agreed. It indicates that the assumptions and the thermodynamic data in this work are valid. Using the adsorption equilibrium constant as a free parameter, the experimental data of iodide and carbonate have been fitted to the model. The model is in a good agreement with the experimental data of the iodide system. (author)

  9. Investigation of sodium - carbon dioxide interactions with calorimetric studies

    International Nuclear Information System (INIS)

    Simon, N.; Latge, C.; Gicquel, L.

    2007-01-01

    The supercritical CO 2 Brayton cycle could be a promising option to enhance the competitiveness of future Sodium fast reactors but it is highly necessary to get thermodynamic and kinetics information on potential sodium-CO 2 chemical reactions and their consequences. We have studied the interaction between Na and CO 2 via calorimetric methods. These methods are able to point out exothermic/endothermic phenomena and to measure heat of chemical reactions. The main feature of the Na/CO 2 interaction seems to be its sharp dependence on temperature. At low temperature, below 500 C degrees, CO 2 and sodium react and exhibit an induction time which decreases when temperature increases. Above 500 C degrees, we observe a global phenomenon with a fast and instantaneous chemical reaction which may be understood as an auto-combustion of CO 2 in sodium. We clearly demonstrated that Na/CO 2 interaction does not proceed as an auto-catalytic process and is more satisfactorily explained by the occurring of an auto-combustion phenomenon

  10. Improving the Corrosion Inhibitive Strength of Sodium Sulphite in Hydrogen Cyanide Solution Using Sodium Benzoate

    OpenAIRE

    Muhammed Olawale Hakeem AMUDA; Olusegun Olusoji SOREMEKUN; Olakunle Wasiu SUBAIR; Atinuke OLADOYE

    2008-01-01

    The improvement in the inhibitive strength of sodium sulphite on corrosion of mild steel in hydrogen cyanide by adding sodium benzoate in regulated volume was investigated using the fundamental weight loss measurement.500 ppm concentration inhibitive mixtures of sodium benzoate and sodium sulphite in three different volume ratios (5/15, 10/10, 15/5) were formulated and studied for corrosion rate in 200ml hydrogen cyanide fluid. Result obtained indicates that the corrosion rate of mild steel i...

  11. A comparative clinical study investigating the efficacy of a test dentifrice containing 8% strontium acetate and 1040 ppm sodium fluoride versus a marketed control dentifrice containing 8% arginine, calcium carbonate, and 1450 ppm sodium monofluorophosphate in reducing dentinal hypersensitivity.

    Science.gov (United States)

    Hughes, Nathan; Mason, Stephen; Jeffery, Peter; Welton, Helen; Tobin, Maira; O'Shea, Caoimhe; Browne, Mairead

    2010-01-01

    The objective of this clinical study was to evaluate and compare the efficacy in reducing dentin hypersensitivity of an 8% strontium acetate, 1040 ppm sodium fluoride dentifrice to a marketed control 8% arginine, calcium carbonate, 1450 ppm sodium monofluorophosphate dentifrice after twice-daily brushing for two, four, and eight weeks. This was a randomized, examiner-blind, two-arm parallel group, eight-week longitudinal clinical study with seventy-nine subjects, stratified based on baseline tooth sensitivity (Schiff score, Yeaple). Subjects brushed with either an 8% strontium acetate-based dentifrice or a marketed 8% arginine calcium carbonate dentifrice twice daily for approximately one minute. At screening, baseline, weeks two, four, and eight, subjects' tooth sensitivity was determined through both evaporative (Schiff and Visual Analogue Scale [VAS]) and tactile stimuli (Yeaple probe). Subject assessments using each stimulus were performed by the same examiner throughout the study. Seventy-seven subjects completed this clinical study. Both subject groups exhibited significant cumulative reductions from baseline to Days 14, 28, and 56 in dentin hypersensitivity as measured by Schiff, Yeaple, and VAS (for the 8% strontium acetate group, p carbonate group, p = 0.0031 for Yeaple at Day 14, p = 0.0015 for VAS at Day 14, and p 0.05) were observed between treatments for any of the time points and measures except for tactile sensitivity at Day 56, for which the 8% strontium acetate-based dentifrice was statistically superior (p = 0.0391) to the control 8% arginine calcium carbonate dentifrice. The 8% strontium acetate, 1040 ppm sodium fluoride dentifrice provided significant reductions in dentin hypersensitivity (p carbonate dentifrice showed no significant differences (p > 0.05) apart from tactile (Yeaple) sensitivity at week 8, where the 8% strontium acetate-based dentifrice showed significant improvement over the control (p = 0.0391).

  12. Experimental study o the sodium-concrete reaction

    International Nuclear Information System (INIS)

    Goncalves, A.C.; Torres, A.R.; Brito Aghina, L.O. de; Messere e Castro, P.

    1986-01-01

    Effects and aspects of security are verified during a sodium leakage in high temperatures on liners of contention cells and directly on the concrete. As this kinetic process involves reactions between materials in solid state (such as oxides and carbonates) vapors and gases (such as water and CO 2 )) with liquid sodium, effects of each phase of the heterogeneous mixture are separately analysed. Are still analysed produced products and briefly discussed the kinetic of the sodium-concrete reaction. (Author) [pt

  13. A quantitative metabolomics study of high sodium response in Clostridium acetobutylicum ATCC 824 acetone-butanol-ethanol (ABE) fermentation

    Science.gov (United States)

    Zhao, Xinhe; Condruz, Stefan; Chen, Jingkui; Jolicoeur, Mario

    2016-01-01

    Hemicellulose hydrolysates, sugar-rich feedstocks used in biobutanol refinery, are normally obtained by adding sodium hydroxide in the hydrolyze process. However, the resulting high sodium concentration in the hydrolysate inhibits ABE (acetone-butanol-ethanol) fermentation, and thus limits the use of these low-cost feedstocks. We have thus studied the effect of high sodium on the metabolic behavior of Clostridium acetobutyricum ATCC 824, with xylose as the carbon source. At a threshold sodium concentration of 200 mM, a decrease of the maximum cell dry weight (−19.50 ± 0.85%) and of ABE yield (−35.14 ± 3.50% acetone, −33.37 ± 0.74% butanol, −22.95 ± 1.81% ethanol) were observed compared to control culture. However, solvents specific productivities were not affected by supplementing sodium. The main effects of high sodium on cell metabolism were observed in acidogenesis, during which we observed the accumulation of ATP and NADH, and the inhibition of the pentose phosphate (PPP) and the glycolytic pathways with up to 80.73 ± 1.47% and 68.84 ± 3.42% decrease of the associated metabolic intermediates, respectively. However, the NADP+-to-NADPH ratio was constant for the whole culture duration, a phenomenon explaining the robustness of solvents specific productivities. Therefore, high sodium, which inhibited biomass growth through coordinated metabolic effects, interestingly triggered cell robustness on solvents specific productivity. PMID:27321153

  14. Application of sodium carbonate prevents sulphur poisoning of catalysts in automated total mercury analysis

    Science.gov (United States)

    McLagan, David S.; Huang, Haiyong; Lei, Ying D.; Wania, Frank; Mitchell, Carl P. J.

    2017-07-01

    Analysis of high sulphur-containing samples for total mercury content using automated thermal decomposition, amalgamation, and atomic absorption spectroscopy instruments (USEPA Method 7473) leads to rapid and costly SO2 poisoning of catalysts. In an effort to overcome this issue, we tested whether the addition of powdered sodium carbonate (Na2CO3) to the catalyst and/or directly on top of sample material increases throughput of sulphur-impregnated (8-15 wt%) activated carbon samples per catalyst tube. Adding 5 g of Na2CO3 to the catalyst alone only marginally increases the functional lifetime of the catalyst (31 ± 4 g of activated carbon analyzed per catalyst tube) in relation to unaltered catalyst of the AMA254 total mercury analyzer (17 ± 4 g of activated carbon). Adding ≈ 0.2 g of Na2CO3 to samples substantially increases (81 ± 17 g of activated carbon) catalyst life over the unaltered catalyst. The greatest improvement is achieved by adding Na2CO3 to both catalyst and samples (200 ± 70 g of activated carbon), which significantly increases catalyst performance over all other treatments and enables an order of magnitude greater sample throughput than the unaltered samples and catalyst. It is likely that Na2CO3 efficiently sequesters SO2, even at high furnace temperatures to produce Na2SO4 and CO2, largely negating the poisonous impact of SO2 on the catalyst material. Increased corrosion of nickel sampling boats resulting from this methodological variation is easily resolved by substituting quartz boats. Overall, this variation enables an efficient and significantly more affordable means of employing automated atomic absorption spectrometry instruments for total mercury analysis of high-sulphur matrices.

  15. Electrochemical Impedance Response of the surface treated FMS in Liquid Sodium Environment

    International Nuclear Information System (INIS)

    Lee, Jeong Hyeon; Shin, Sang Hun; Kim, Ji Hyun

    2014-01-01

    HT9 and Gr.92 are known as compatible in sodium environment because the usual refueling time of SFRs is designed about 54 months. It is very important to investigate the corrosion-related behavior such as surface corrosion rate, carburization, decarburization and mechanical properties for its operation time. SiC and Si 3 N 4 CVD coating for decarburization barrier on the surface of FMS is considered in this study. The decarburization process where dissolved carbon near the specimen surface disused in to the liquid sodium. This process can originate from the difference between dissolved carbon in the material and liquid sodium. A compatibility test the cladding tube revealed that a decrease of the mechanical property instigated by the aging proves governed the whole mechanical property. To monitor the corrosion behavior of these candidate materials in sodium environment, Electrochemical Impedance Spectroscopy (EIS) method is first introduced and investigated in this study. The compatibility of cladding and structural materials with sodium has to be carefully investigated, as sodium could promote corrosion of cladding and structural materials in two ways. One is produced by the dissolution of alloy constituents into the sodium, and the other is produced through a chemical reaction with impurities (especially oxygen and carbon) in the sodium environment. EIS test with pre-oxidized Gr. 92 specimen in 200 .deg. C liquid sodium environment was carried out in this study. A clear Nyquist and Bode plots were obtained in liquid metal environment and the resistance of sodium and the oxide, and the capacitance of the oxide were measured from this result

  16. Synergistic Inhibition of Carbon Steel Corrosion by Inhibitor-Blends in Chloride-Containing Simulated Cooling Water

    Energy Technology Data Exchange (ETDEWEB)

    Shaban, Abdul; Felhosi, Ilona [Hungarian Academy of Sciences, Budapest (Hungary); Vastag, Gyongyi [University of Novi Sad, Novi Sad (Serbia)

    2017-06-15

    The objective of this work was to develop efficient synergistic inhibitor combinations comprising sodium nitrite (NaNO{sub 2}) and an inhibitor-blend code named (SN-50), keeping in view of their application in industrial cooling water systems. The electrochemical characteristics of the carbon steel working electrode in simulated cooling water (SCW), without and with the addition of different combinations of the inhibitors, were investigated using electrochemical impedance spectroscopy (EIS), open circuit potential (OCP). The electrode surface changes were followed by visual characterization methods. It was demonstrated in this study that all the combinations of the inhibitors exhibited synergistic benefit and higher inhibition efficiencies than did either of the individual inhibitors. The addition of SN-50 inhibitor to the SCW shifted the OCP to more anodic values and increased the polarization resistance (R{sub p}) values of carbon steel at all applied concentrations. The higher the applied sodium nitrite concentration (in the protection concentration range), the higher the obtained R{sub p} values and the inhibition efficiency improved by increasing the inhibitor concentration.

  17. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of health claims related to carbonate and bicarbonate salts of sodium and potassium and maintenance of normal bone (ID 331, 1402) pursuant to Article 13(1) of Regulation (EC) No 1924/2006

    DEFF Research Database (Denmark)

    Tetens, Inge

    claims in relation to carbonate and bicarbonate salts of sodium and potassium and maintenance of normal bone. The scientific substantiation is based on the information provided by the Member States in the consolidated list of Article 13 health claims and references that EFSA has received from Member...... States or directly from stakeholders. The food constituents that are the subject of the health claim are carbonate and bicarbonate salts of sodium and potassium. The Panel considers that carbonate and bicarbonate salts of sodium and potassium are sufficiently characterised. The claimed effects are “acid...... the dietary intake of carbonate or bicarbonate salts of sodium or potassium and maintenance of normal bone....

  18. Comparison of manufactured and black carbon nanoparticle concentrations in aquatic sediments

    International Nuclear Information System (INIS)

    Koelmans, A.A.; Nowack, B.; Wiesner, M.R.

    2009-01-01

    In this paper, we show that concentrations of manufactured carbon-based nanoparticles (MCNPs) in aquatic sediments will be negligible compared to levels of black carbon nanoparticles (BCNPs). This is concluded from model calculations accounting for MCNP sedimentation fluxes, removal rates due to aggregation or degradation, and MCNP burial in deeper sediment layers. The resultant steady state MCNP levels are compared with BCNP levels calculated from soot levels in sediments and weight fractions of nanosized fractions of these soot particles. MCNP/BCNP ratios range from 10 -7 to 10 -4 (w:w). This suggests that the often acclaimed effect of MCNPs on organic pollutant binding and bioavailability will likely be below the level of detection if natural BCNPs are present, even if binding to MCNP is one to two orders of magnitude stronger than to BCNPs. Furthermore, exposure and toxic effects of MCNPs in sediments and soils will be negligible compared to that of BCNPs. - Concentrations of manufactured carbon-based nanoparticles in sediments and soils will be negligible compared to levels of black carbon (soot) nanoparticles

  19. Influence of the concentration of carbon nanotubes on electrical ...

    Indian Academy of Sciences (India)

    Influence of the concentration of carbon nanotubes on electrical conductivity of magnetically aligned MWCNT–polypyrrole composites. KAVEH KAZEMIKIA1,∗, FAHIMEH BONABI2, ALI ASADPOORCHALLO3 and. MAJID SHOKRZADEH4. 1Department of Electrical and Computer Engineering, Islamic Azad University, Bonab ...

  20. Capacitance-Assisted Sustainable Electrochemical Carbon Dioxide Mineralisation.

    Science.gov (United States)

    Lamb, Katie J; Dowsett, Mark R; Chatzipanagis, Konstantinos; Scullion, Zhan Wei; Kröger, Roland; Lee, James D; Aguiar, Pedro M; North, Michael; Parkin, Alison

    2018-01-10

    An electrochemical cell comprising a novel dual-component graphite and Earth-crust abundant metal anode, a hydrogen producing cathode and an aqueous sodium chloride electrolyte was constructed and used for carbon dioxide mineralisation. Under an atmosphere of 5 % carbon dioxide in nitrogen, the cell exhibited both capacitive and oxidative electrochemistry at the anode. The graphite acted as a supercapacitive reagent concentrator, pumping carbon dioxide into aqueous solution as hydrogen carbonate. Simultaneous oxidation of the anodic metal generated cations, which reacted with the hydrogen carbonate to give mineralised carbon dioxide. Whilst conventional electrochemical carbon dioxide reduction requires hydrogen, this cell generates hydrogen at the cathode. Carbon capture can be achieved in a highly sustainable manner using scrap metal within the anode, seawater as the electrolyte, an industrially relevant gas stream and a solar panel as an effective zero-carbon energy source. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  1. Bilateral {sup 23}Na MR imaging of the breast and quantification of sodium concentration; Bilaterale {sup 23}Na-MR-Bildgebung der Mamma und Quantifizierung der Natriumkonzentration

    Energy Technology Data Exchange (ETDEWEB)

    Danisch, Meike; Kalayciyan, Raffi; Schad, Lothar R. [Heidelberg Univ., Mannheim (Germany). Computerunterstuetzte Klinische Medizin; Wetterling, Friedrich [Trinity College Dublin (Ireland)

    2014-03-01

    A novel setup for {sup 23}Na MRI, which allows bilateral imaging of the breast, is presented. For this purpose a figure-eight receive-only {sup 23}Na surface coil was developed. For our experiments on three samples with NaCl solutions of different sodium concentrations and two female subjects we used an asymmetric birdcage coil in transmit mode and the developed surface coil for receiving the signal at 3 T. Imaging of the samples showed the applicability of the employed normalization method for measuring the distribution of sodium concentration. In a sample of concentration [Na{sup +}] = 51 mM we achieved SNR = 70 at a nominal isotropic resolution of 2,5 mm (T{sub R} = 66 ms, T{sub E} = 0,6 ms, T{sub A} = 20 min). Furthermore we showed that by means of this setup it is possible to quantify the sodium concentration in breast tissue (TSC) of a female subject with an accuracy of 23% (T{sub R} = 150 ms, T{sub E} = 0,5 ms, T{sub A} = 45 min). (orig.)

  2. The Effect of Carbon Source and Fluoride Concentrations in the "Streptococcus Mutans" Biofilm Formation

    Science.gov (United States)

    Paulino, Tony P.; Andrade, Ricardo O.; Bruschi-Thedei, Giuliana C. M.; Thedei, Geraldo, Jr.; Ciancaglini, Pietro

    2004-01-01

    The main objective of this class experiment is to show the influence of carbon source and of different fluoride concentrations on the biofilm formation by the bacterium "Streptococcus mutans." The observation of different biofilm morphology as a function of carbon source and fluoride concentration allows an interesting discussion regarding the…

  3. Measurements of hydrogen concentration in liquid sodium by using an inert gas carrier method

    International Nuclear Information System (INIS)

    Funada, T.; Nihei, I.; Yuhara, S.; Nakasuji, T.

    1979-01-01

    A technique was developed to measure the hydrogen level in liquid sodium using an inert gas carrier method. Hydrogen was extracted into an inert gas from sodium through a thin nickel membrane in the form of a helically wound tube. The amount of hydrogen in the inert gas was analyzed by gas chromatography. The present method is unique in that it can be used over the wide range of sodium temperatures (150 to 700 0 C) and has no problems associated with vacuum systems. The partial pressure of hydrogen in sodium was determined as a function of cold-trap temperature (T/sub c/). Sieverts' constant (K/sub s/) was determined as a function of sodium temperature (T). From Sieverts' constant, the solubility of hydrogen in sodium is calculated. It was found that other impurities in sodium, such as (O) and (OH), have little effect on the hydrogen pressure in the sodium loop

  4. Experimental study on oxidation and combustion characteristics of sodium droplets

    International Nuclear Information System (INIS)

    Zhang Zhigang; Sun Shubin; Liu Chongchong; Tang Yexin

    2015-01-01

    In the operation of the sodium-cooled fast reactor, the accident caused by the leakage and combustion of liquid sodium is common and frequent. In this paper, the oxidation and combustion characteristics of sodium droplets were studied by carrying out the experiments of the oxidation and combustion under different conditions of initial temperatures (140-370℃) of the sodium droplets and oxygen concentrations (4%-21%). The oxidation and combustion behaviors were visualized by a set of combustion apparatus of sodium droplet and a high speed camera. The experiment results show that the columnar oxides grow longer as the initial temperature of sodium droplet and oxygen concentration become lower. Under the same oxygen concentration condition, the sodium droplet with the higher initial temperature is easier to ignite and burn. When the initial temperature of sodium droplet is below 200℃, it is very difficult to ignite. If there is a turbulence damaging the oxide layer on the surface, the sodium droplet will also burn gradually. When the initial temperature ranges from 140℃ to 370℃ and the oxygen fraction is equal to or higher than 12%, the sodium droplet could burn completely and the maximum combustion temperature could roughly reach 600-800℃. When the oxygen concentration is below 12%, the sodium droplet could not burn completely and the highest combustion temperature is below 600℃. The results are helpful to the research on the columnar flow and spray sodium fire. (authors)

  5. Development of sodium disposal technology. Experiment of sodium compound solidification process

    International Nuclear Information System (INIS)

    Matsumoto, Toshiyuki; Ohura, Masato; Yatoh, Yasuo

    2007-07-01

    A large amount of sodium containing radioactive waste will come up at the time of final shutdown/decommission of FBR plant. The radioactive waste is managed as solid state material in a closed can in Japan. As for the sodium, there is no established method to convert the radioactive sodium to solid waste. Further, the sodium is highly reactive. Thus, it is recommended to convert the sodium to a stable substance before the solidification process. One of the stabilizing methods is conversion of sodium into sodium hydroxide solution. These stabilization and solidification processes should be safe, economical, and efficient. In order to develop such sodium disposal technology, nonradioactive sodium was used and a basic experiment was performed. Waste-fluid Slag Solidification method was employed as the solidification process of sodium hydroxide solution. Experimental parameters were mixing ratio of the sodium hydroxide and the slag solidification material, temperature and concentration of the sodium hydroxide. The best parameters were obtained to achieve the maximum filling ratio of the sodium hydroxide under a condition of enough high compressive strength of the solidified waste. In a beaker level test, the solidified waste was kept in a long term and it was shown that there was no change of appearance, density, and also the compressive strength was kept at a target value. In a real scale test, homogeneous profiles of the density and the compressive strength were obtained. The compressive strength was higher than the target value. It was shown that the Waste-fluid Slag Solidification method can be applied to the solidification process of the sodium hydroxide solution, which was produced by the stabilization process. (author)

  6. Hydrogen meter for service in liquid sodium

    International Nuclear Information System (INIS)

    McCown, J.J.

    1983-11-01

    This standard establishes the requirements for the design, materials, fabrication, quality assurance, examination, and acceptance testing of a hydrogen meter and auxiliary equipment for use in radioactive or nonradioactive liquid sodium service. The meter shall provide a continuous and accurate indication of the hydrogen impurity concentration over the range 0.03 to 10 ppM hydrogen in sodium at temperatures between 800 and 1000 0 F (427 and 538 0 C). The meter may also be used to rapidly monitor changes in hydrogen concentration, over the same concentration range, and, therefore can be used as a sensor for sodium-water reactions in LMFBR steam generators

  7. Lithium and sodium ion capacitors with high energy and power densities based on carbons from recycled olive pits

    Science.gov (United States)

    Ajuria, Jon; Redondo, Edurne; Arnaiz, Maria; Mysyk, Roman; Rojo, Teófilo; Goikolea, Eider

    2017-08-01

    In this work, we are presenting both lithium and sodium ion capacitors (LIC and NIC) entirely based on electrodes designed from recycled olive pit bio-waste derived carbon materials. On the one hand, olive pits were pyrolized to obtain a low specific surface area semigraphitic hard carbon to be used as the ion intercalation (battery-type) negative electrode. On the other hand, the same hard carbon was chemically activated with KOH to obtain a high specific surface area activated carbon that was further used as the ion-adsorption (capacitor-type) positive electrode. Both electrodes were custom-made to be assembled in a hybrid cell to either build a LIC or NIC in the corresponding Li- and Na-based electrolytes. For comparison purposes, a symmetric EDLC supercapacitor cell using the same activated carbon in 1.5 M Et4NBF4/acetonitrile electrolyte was also built. Both LIC and NIC systems demonstrate remarkable energy and power density enhancement over its EDLC counterpart while showing good cycle life. This breakthrough offers the possibility to easily fabricate versatile hybrid ion capacitors, covering a wide variety of applications where different requirements are demanded.

  8. Effect of tooth-bleaching on the carbonate concentration in dental enamel by Raman spectroscopy.

    Science.gov (United States)

    Vargas-Koudriavtsev, Tatiana; Herrera-Sancho, Óscar-Andrey

    2017-01-01

    There are not many studies evaluating the effects of surface treatments at the molecular level. The aim of this in vitro study was to analyze the concentration of carbonate molecules in dental enamel by Raman spectroscopy after the application of in-office and home whitening agents. Sixty human teeth were randomly divided into six groups and exposed to three different home bleaching gels (Day White) and three in-office whitening agents (Zoom! Whitespeed and PolaOffice) according to the manufacturer´s instructions. The concentration of carbonate molecules in enamel was measured prior to and during the treatment by means of Raman spectroscopy. Statistical analysis included repeated measures analysis of variance ( p ≤0.05) and Bonferroni pairwise comparisons. At home bleaching agents depicted a decrease in the carbonate molecule. This decrease was statistically significant for the bleaching gel with the highest hydrogen peroxide concentration ( p ≤0,05). In-office whitening agents caused an increase in carbonate, which was significant for all three groups ( p ≤0,05). In-office bleaching gels seem to cause a gain in carbonate of the enamel structure, whilst at-home whitening gels caused a loss in carbonate. Key words: Bleaching, whitening, hydrogen peroxide, carbamide peroxide, Raman spectroscopy, carbonate.

  9. Nontoxic concentration of ceftazidime and flomoxef sodium for intravitreal use--evaluated by in-vitro ERG.

    Science.gov (United States)

    Tanabe, J; Kitano, K; Suzuki, T; Okayama, Y; Mochizuki, K; Kawasaki, K

    1990-01-01

    The effects of ceftazidime (CAZ) and flomoxef sodium (FMOX) on the in-vitro electroretinogram (ERG) of albino rabbits were studied. The a-wave, the b-wave and the oscillatory potential (OP) were unchanged by 0.3mM (0.19mg/ml) CAZ-containing solution. The OP was suppressed by 0.5mM (0.32mg/ml) CAZ. The a-wave, the b-wave and the OP were unchanged by 0.5mM (0.26mg/ml) FMOX. The OP was suppressed and its peak latency was delayed by 2mM (0.52mg/ml) FMOX. The concentration of 0.3mM (0.19mg/ml) CAZ was higher than its minimum inhibitory concentration (MIC) against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Serratia marcescens and Propionibacterium acnes. The concentration of 0.5mM (0.26mg/ml) FMOX was higher than its MIC against Staphylococcus aureus, Staphylococcus epidermidis, Serratia marcescens and Propionibacterium acnes.

  10. Methods for the sodium cooled fast reactor fire safety provisions

    International Nuclear Information System (INIS)

    Gryaznov, B.V.; Dergachev, N.P.

    1983-01-01

    Problems of fire safety provision on NPPs with sodium cooled fast reactor are under discussion. Methods of sodium leak localization, measures eliminating sodium flaring up during leaks and main means of sodium fire extinguishing are considered. An extinguishing of sodium flaring up is performed by means of sodium temperatUre decrease and by limitation of hydrogen access to the flaring up surface. A conclusion is made that the most effective methods of extinguishing are the following: self-extinguishing (due to hydrogen burning out in a limiting volume); extinguishing by a gas mixture of nitrogen and carbonic acid (initial filling and blowing of rooms during sodium flaring up); extinguishing by special powders

  11. Potential use of the facultative halophyte Chenopodium quinoa Willd. as substrate for biogas production cultivated with different concentrations of sodium chloride under hydroponic conditions.

    Science.gov (United States)

    Turcios, Ariel E; Weichgrebe, Dirk; Papenbrock, Jutta

    2016-03-01

    This project analyses the biogas potential of the halophyte Chenopodium quinoa Willd. In a first approach C. quinoa was grown with different concentrations of NaCl (0, 10 and 20 ppt NaCl) and the crop residues were used as substrate for biogas production. In a second approach, C. quinoa was grown with 0, 10, 20 and 30 ppt NaCl under hydroponic conditions and the fresh biomass was used as substrate. The more NaCl is in the culture medium, the higher the sodium, potassium, crude ash and hemicellulose content in the plant tissue whereas the calcium, sulfur, nitrogen and carbon content in the biomass decrease. According to this study, it is possible to produce high yields of methane using biomass of C. quinoa. The highest specific methane yields were obtained using the substrate from the plants cultivated at 10 and 20 ppt NaCl in both experiments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Effect of sodium environment on the creep-rupture and low-cycle fatigue behavior of austenitic stainless steels

    International Nuclear Information System (INIS)

    Natesan, K.; Chopra, D.K.; Zeman, G.J.; Smith, D.L.; Kassner, T.F.

    1977-01-01

    Austenitic stainless steels used for in-core structural components, piping, valves, and the intermediate heat exchanger in Liquid-Metal Fast-Breeder Reactors (LMFBRs) are subjected to sodium at elevated temperatures and to complex stress conditions. As a result, the materials can undergo compositional and microstructural changes as well as mechanical deformation by creep and cyclic fatigue processes. In the present paper, information is presented on the creep-rupture and low-cycle fatigue behavior of Types 304 and 316 stainless steel in the solution-annealed condition and after long-term exposure to flowing sodium. The nonmetallic impurity-element concentrations in the sodium were controlled at levels similar to those in EBR-II primary sodium. Strain-time relationships developed from the experimental creep data were used to generate isochronous stress-creep strain curves as functions of sodium-exposure time and temperature. The low-cycle fatigue data were used to obtain relationships between plastic strain range and cycles-to-failure based on the Coffin-Manson formalism and a damage-rate approach developed at ANL. An analysis of the cyclic stress-strain behavior of the materials showed that the strain-hardening rates for the sodium-exposed steels were larger than those for the annealed material. However, the sodium-exposed specimens showed significant softening, as evidenced by the lower stress at half the fatigue life. Microstructural information obtained from the different specimens suggests that crack initiation is more difficult in the long-term sodium-exposed specimens when compared with the solution-annealed material. Based on the expected carbon concentrations in LMFBR primary system sodium, moderate carburization of the austenitic stainless steels will not degrade the mechanical properties to a significant extent, and therefore, will not limit the performance of out-of-core components. (author)

  13. Corrosion by concentrated sulfuric acid in carbon steel pipes and tanks: state of the art

    Energy Technology Data Exchange (ETDEWEB)

    Panossian, Zehbour; Almeida, Neusvaldo Lira de; Sousa, Raquel Maria Ferreira de [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil); Pimenta, Gutemberg de Souza [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas e Desenvolvimento (CENPES); Marques, Leandro Bordalo Schmidt [PETROBRAS Engenharia, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    PETROBRAS, allied to the policy of reduction of emission of pollutants, has been adjusting the processes of the new refineries to obtain products with lower sulfur content. Thus, the sulfur dioxide, extracted from the process gases of a new refinery to be built in the Northeast, will be used to produce sulfuric acid with concentration between (94-96) %. This acid will be stored in carbon steel tanks and transported through a buried 8-km carbon steel pipe from the refinery to a pier, where it will be loaded onto ships and sent to the consumer markets. Therefore, the corrosion resistance of carbon steel by concentrated acid will become a great concern for the mentioned storage and transportation. When the carbon steel comes into contact with concentrated sulfuric acid, there is an immediate acid attack with the formation of hydrogen gas and ferrous ions which, in turn, forms a protective layer of FeSO{sub 4} on the metallic surface. The durability of the tanks and pipes made of carbon steel will depend on the preservation of this protective layer. This work presents a review of the carbon steel corrosion in concentrated sulfuric acid and discusses the preventive methods against this corrosion, including anodic protection. (author)

  14. Study on Bleaching Technology of Cotton Fabric with Sodium Percarbonate

    OpenAIRE

    Li Zhi; Wang Yanling; Wang Zhichao

    2016-01-01

    Bleach cotton fabric with sodium percarbonate solution. Analyse of the effect of the concentration of sodium percarbonate solution, bleaching time, bleaching temperature and the light radiation on the bleaching effect of fabric.The result shows that increasing concentrations of percarbonate,increasing the bleaching time , raising the bleaching temperature and the UV irradiation may whiten the cotton fabric.The most suitable conditions for the bleaching process is concentration of sodium perca...

  15. Simulation of creep test on 316FR stainless steel in sodium environment at 550degC

    International Nuclear Information System (INIS)

    Satmoko, A.; Asayama, Tai

    1999-04-01

    In sodium environment, material 316FR stainless steel risks to suffer from carburization. In this study, an analysis using a Fortran program is conducted to evaluate the carbon influence on the creep behavior of 316FR based on experimental results from uni-axial creep test that had been performed at temperature 550degC in sodium environment simulating Fast Breeder Reactor condition. As performed in experiments, two parts are distinguished. At first, elastic-plastic behavior is used to simulate the fact that just before the beginning of creep test, specimen suffers from load or stress much higher than initial yield stress. In second part, creep condition occurs in which the applied load is kept constant. The plastic component should be included, since stresses increase due to section area reduction. For this reason, elastic-plastic-creep behavior is considered. Through time carbon penetration occurs and its concentration is evaluated empirically. This carburization phenomena are assumed to affect in increasing yield stress, decreasing creep strain rate, and increasing creep rupture strength of material. The model is capable of simulating creep test in sodium environment. Material near from surface risks to be carburized. Its material properties change leading to non-uniform distribution of stresses. Those layers of material suffer from stress concentration, and are subject to damage. By introducing a damage criteria, crack initialization can thus be predicted. And even, crack growth can be evaluated. For high stress levels, tensile strength criterion is more important than creep damage criterion. But in low stress levels, the latter gives more influence in fracture. Under high stress, time to rupture of a specimen in sodium environment is shorter than in air. But for stresses lower than 26 kgf/mm 2 , the time to rupture of creep in sodium environment is the same or little longer than in air. Quantitatively, the carburization effect at 550degC is not important. This

  16. Adsorption characteristics of activated carbon hollow fibers

    Directory of Open Access Journals (Sweden)

    B. V. Kaludjerović

    2009-01-01

    Full Text Available Carbon hollow fibers were prepared with regenerated cellulose or polysulfone hollow fibers by chemical activation using sodium phosphate dibasic followed by the carbonization process. The activation process increases the adsorption properties of fibers which is more prominent for active carbone fibers obtained from the cellulose precursor. Chemical activation with sodium phosphate dibasic produces an active carbon material with both mesopores and micropores.

  17. Adsorption of Crystal Violet on Activated Carbon Prepared from Coal Flotation Concentrate

    Science.gov (United States)

    Aydogmus, Ramazan; Depci, Tolga; Sarikaya, Musa; Riza Kul, Ali; Onal, Yunus

    2016-10-01

    The objective of this study is firstly to investigate the floatability properties of Zilan- Van coal after microwave irradiation and secondly to produce activated carbon from flotation concentrate in order to remove Crystal Violet (CV) from waste water. The flotation experiments showed that microwave heating at 0.9 kW power level for 60 sec exposure time enhanced the hydrophobicity and increased the flotation yield. The activated carbon with remarkable surface area (696 m2/g) was produced from the flotation concentrate and used to adsorb CV from aqueous solution in a batch reactor at different temperature. The adsorption properties of CV onto the activated carbon are discussed in terms of the adsorption isotherms (Langmuir and Freundlich) and found that the experimental results best fitted by the Langmuir model.

  18. Theoretical assessment of particle generation from sodium pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M., E-mail: monica.gmartin@ciemat.es [CIEMAT, Unit of Nuclear Safety Research, Av. Complutense, 40, 28040 Madrid (Spain); Herranz, L.E., E-mail: luisen.herranz@ciemat.es [CIEMAT, Unit of Nuclear Safety Research, Av. Complutense, 40, 28040 Madrid (Spain); Kissane, M.P., E-mail: Martin.KISSANE@oecd.org [Nuclear Safety Technology and Regulation Division, OECD Nuclear Energy Agency (NEA), 46 quai Alphonse Le Gallo, 92100 Boulogne-Billancourt (France)

    2016-12-15

    Highlights: • Development of particle generation model for sodium-oxides aerosol formation. • Development of partially validated numerical simulations to build up maps of saturation ratio. • Nucleation of supersaturated vapours as relevant source of aerosols over sodium pools. • Prediction of high concentrations of primary particles in the combustion zone. - Abstract: Potential sodium discharge in the containment during postulated Beyond Design Basis Accidents (BDBAs) in Sodium-cooled Fast Reactors (SFRs) would have major consequences for accident development in terms of energetics and source term. In the containment, sodium vaporization and subsequent oxidation would result in supersaturated oxide vapours that would undergo rapid nucleation creating toxic aerosols. Therefore, modelling this vapour nucleation is essential to proper source term assessment in SFRs. In the frame of the EU-JASMIN project, a particle generation model to calculate the particle generation rate and their primary size during an in-containment sodium pool fire has been developed. Based on a suite of individual models for sodium vaporization, oxygen natural circulation (3D modelling), sodium-oxygen chemical reactions, sodium-oxides-vapour nucleation and condensation, its consistency has been partially validated by comparing with available experimental data. As an outcome, large temperature and vapour concentration gradients set over the sodium pool have been found which result in large particle concentrations in the close vicinity of the pool.

  19. Technology for sodium purity control

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ji Young; Kim, B. H.; Kim, T. J. [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-10-01

    When sodium is used as heat transfer fluid, the plugging in coolant flow, the corrosion of structure material and the transfer of radioactive material caused by the impurities in sodium are worth considerable. Accordingly, these impurities must be monitored and controlled continuously by sodium purification devices in the heat transfer system which sodium is used as coolant. Sodium purification loop was constructed for the purpose of accumulating the technology for purity control of the coolant, developing and verifying further efficient instruments for sodium purification. The plugging meter and the cold trap is used as the implement for measuring and controlling the oxygen and the hydrogen, the main impurities in sodium coolant. They are capable of excellent performance as the implements which could detect and monitor the impurities to the concentration limit required for nuclear reactor. Sodium purification loop could be used variably according to the experimental purpose. 18 refs., 34 figs., 8 tabs. (Author)

  20. Kinetics of absorption of carbon dioxide in aqueous amine and carbonate solutions with carbonic anhydrase

    NARCIS (Netherlands)

    Penders-van Elk, Nathalie J. M. C.; Hamborg, Espen S.; Huttenhuis, Patrick J. G.; Fradette, Sylvie; Carley, Jonathan A.; Versteeg, Geert F.

    In the present work the absorption of carbon dioxide in aqueous N-methyldiethanolamine (MDEA) and aqueous sodium carbonate with and without carbonic anhydrase (CA) was studied in a stirred cell contactor in the temperature range 298-333 K. The CA was present as free enzyme and is compared to the

  1. Final report on the safety assessment of sodium sulfite, potassium sulfite, ammonium sulfite, sodium bisulfite, ammonium bisulfite, sodium metabisulfite and potassium metabisulfite.

    Science.gov (United States)

    Nair, Bindu; Elmore, Amy R

    2003-01-01

    Sodium Sulfite, Ammonium Sulfite, Sodium Bisulfite, Potassium Bisulfite, Ammonium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite are inorganic salts that function as reducing agents in cosmetic formulations. All except Sodium Metabisulfite also function as hair-waving/straightening agents. In addition, Sodium Sulfite, Potassium Sulfite, Sodium Bisulfite, and Sodium Metabisulfite function as antioxidants. Although Ammonium Sulfite is not in current use, the others are widely used in hair care products. Sulfites that enter mammals via ingestion, inhalation, or injection are metabolized by sulfite oxidase to sulfate. In oral-dose animal toxicity studies, hyperplastic changes in the gastric mucosa were the most common findings at high doses. Ammonium Sulfite aerosol had an acute LC(50) of >400 mg/m(3) in guinea pigs. A single exposure to low concentrations of a Sodium Sulfite fine aerosol produced dose-related changes in the lung capacity parameters of guinea pigs. A 3-day exposure of rats to a Sodium Sulfite fine aerosol produced mild pulmonary edema and irritation of the tracheal epithelium. Severe epithelial changes were observed in dogs exposed for 290 days to 1 mg/m(3) of a Sodium Metabisulfite fine aerosol. These fine aerosols contained fine respirable particle sizes that are not found in cosmetic aerosols or pump sprays. None of the cosmetic product types, however, in which these ingredients are used are aerosolized. Sodium Bisulfite (tested at 38%) and Sodium Metabisulfite (undiluted) were not irritants to rabbits following occlusive exposures. Sodium Metabisulfite (tested at 50%) was irritating to guinea pigs following repeated exposure. In rats, Sodium Sulfite heptahydrate at large doses (up to 3.3 g/kg) produced fetal toxicity but not teratogenicity. Sodium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite were not teratogenic for mice, rats, hamsters, or rabbits at doses up to 160 mg/kg. Generally, Sodium Sulfite, Sodium

  2. FFTF sodium and cover gas characterization and purification

    International Nuclear Information System (INIS)

    McCown, J.J.; Bloom, G.R.; Meadows, G.E.; Mettler, G.W.

    1980-02-01

    The FFTF Primary and Secondary Heat Transport System (HTS) sodium is purified with cold traps which have packed crystallizers and external economizers. The Primary HTS cold trap is NaK cooled and the Secondary HTS cold traps are air cooled. The FFTF cold traps have maintained high purity in the sodium since sodium fill. Plant operational procedures during fill and initial sodium heatup to 800 0 F were controlled to assure low release rates of impurities to the sodium. The FFTF sodium systems are monitored by plugging temperature indicators and by several sampling methods. During reactor fill and non-fueled operations at 400 to 800 0 F, impurity changes in the sodium were followed by continuous plugging indicator coverage, by exposing wires and foils to measure carbon, hydrogen and oxygen, and by bulk sample analysis of all other trace constituents. The sampling and analysis methods and data are presented, impurity excursions in the cover gas and sodium are described, and impurity trends are discussed

  3. Additional calcium carbonate into concentrate diet for sheep fed ensiled king grass as a based-diet

    Directory of Open Access Journals (Sweden)

    I-W Mathius

    1997-10-01

    Full Text Available In order to ascertain the effect of additional calcium carbonate into concentrate diet, on the performance of sheep fed ensiled king grass as a basal diet, a trial was conducted using 28 growing sheep ( average body weight 17 _+ 1 .4 kg. Based on body weight, the animals were grouped and randomized into four dietary treatments in block randomized design . Dietary treatments were (i chopped king grass + 400 g of concentrate, (ii ensiled king grass + 400 g concentrate + 0 % of calcium carbonate, (iii ensiled king grass + 400 g concentrate + 5 % calcium carbonate and (iv ensiled king grass + 400 g concentrate + 10 % calcium carbonate . Results showed that offering 5 % of calcium carbonate into concentrate diet increased (P 0 .05 for all groups . No differences in the apparent digestibility of the nutrient components were observed, but crude protein decreased significantly (P < 0 .05 . A significant relationship ( P < 0 .01 was found between nitrogen intake (NI and nitrogen retention (NR, and the equation was NR = - 0.1848 + 0.3788 NI ( r = 0.9 . Based on data found that feeding only ensiled king grass as a single diet could not meet the maintenance requirement of energy and protein, therefore, additional energy and crude protein sources is needed .

  4. Flue Gas Desulfurization by Mechanically and Thermally Activated Sodium Bicarbonate

    Directory of Open Access Journals (Sweden)

    Walawska Barbara

    2014-09-01

    Full Text Available This paper presents the results of study on structural parameters (particle size, surface area, pore volume and the sorption ability of mechanically and thermally activated sodium bicarbonate. The sorption ability of the modified sorbent was evaluated by: partial and overall SO2 removal efficiency, conversion rate, normalized stoichiometric ratio (NSR. Sodium bicarbonate was mechanically activated by various grinding techniques, using three types of mills: fluid bed opposed jet mill, fine impact mill and electromagnetic mill, differing in grinding technology. Grounded sorbent was thermally activated, what caused a significant development of surface area. During the studies of SO2 sorption, a model gas with a temperature of 300°C, of composition: sulfur dioxide at a concentration of 6292 mg/mn3, oxygen, carbon dioxide and nitrogen as a carrier gas, was used. The best development of surface area and the highest SO2 removal efficiency was obtained for the sorbent treated by electromagnetic grinding, with simultaneous high conversion rate.

  5. The influence of activating agents on the performance of rice husk-based carbon for sodium lauryl sulfate and chrome (Cr) metal adsorptions

    Science.gov (United States)

    Arneli; Safitri, Z. F.; Pangestika, A. W.; Fauziah, F.; Wahyuningrum, V. N.; Astuti, Y.

    2017-02-01

    This research aims to study the influence of activating agents to produce rice husk based-carbon with high adsorption capacity and efficiency for either hazardous organic molecules or heavy metals which are unfriendly for the environment. Firstly, rice husk was burned by pyrolysis at different temperatures to produce rice husk-based carbon. To improve its ability as an adsorbent, carbon was treated with activating agents, namely, H3PO4 and KOH at room and high temperature (420 °C). The performance of carbon was then tested by contacting it with surfactant (SLS). Finally, the surfactant-modified active carbon was applied for chrome metal removal. The result shows that activation of carbon using phosphate acid (H3PO4) was more effective than potassium hydroxide (KOH) conducted at high temperature to adsorb sodium lauryl sulfate (SLS) and chrome metal with the adsorption capacity 1.50 mgg-1 and 0.375 mgg-1, respectively.

  6. Using Sodium Hydrogen Carbonate for Foaming Polymers

    Directory of Open Access Journals (Sweden)

    Satin Lukáš

    2016-09-01

    Full Text Available All plastics products are made of the essential polymer mixed with a complex blend of materials known collectively as additives. Without additives, plastics would not work, but with them, they can be made safer, cleaner, tougher and more colourful. Additives cost money, but by reducing production costs and making products live longer, they help us save money and conserve the world's precious raw material reserves. In fact, our world would be a lot less safe, a lot more expensive and a great deal duller without the additives that turn basic polymers into useful plastics. One of these additives is sodium bicarbonate. Influence of sodium bicarbonate on properties of the product made of polystyrene was observed in the research described in this paper. Since polystyrene is typically used as a material for electrical components, the mechanical properties of tensile strength and inflammability were measured as a priority. Inflammability parameters were measured using a cone calorimeter.

  7. Liquid sodium oxygenmeter

    International Nuclear Information System (INIS)

    Jakes, D.; Fresl, M.; Svoboda, V.

    1979-02-01

    The results of test runs of two design varieties of liquid sodium oxygenmeter in sodium loops are described. The accuracy and sensitivity are discussed reached using this instrument within 1 and 10 p.p.m. of oxygen concentration. A change in the used reference system is proposed based on practical experiences and thermochemical calculations. Ceramic electrolyte corrosion is analysed and the possible interpretation of the corrosion effect on the galvanic cell electromotive force is suggested. (author)

  8. Hideout of sodium salts in tubesheet crevices: Final report

    International Nuclear Information System (INIS)

    Brunet, J.P.; Campon, J.L.

    1987-07-01

    The hideout of sodium hydroxide and sodium chloride in tubesheet crevices was studied in single tube model boilers at CADARACHE. Radioactive Na 24 was used for the measurements. Crevices of 0.2 mm width were empty or packed. A hydraulically expanded crevice and a rolled crevice were also studied. The concentration rate depends on the bulk water concentration but the equilibrium concentration appears to be related only to thermal conditions. The equilibrium value of 25 moles per liter in the crevice was extrapolated, the sodium concentration in the bulk water being in the range of 5 to 50 ppM. This equilibrium will be obtained with an ''integrated pollution'' of 5000 to 10,000 ppM x hours. Flushing produced by the boiler depressurization was shown to be an effective way to remove salt from the crevice. Sodium hydroxide was shown to concentrate even in a residual crevice of few μm width

  9. Improving the Corrosion Inhibitive Strength of Sodium Sulphite in Hydrogen Cyanide Solution Using Sodium Benzoate

    Directory of Open Access Journals (Sweden)

    Muhammed Olawale Hakeem AMUDA

    2008-12-01

    Full Text Available The improvement in the inhibitive strength of sodium sulphite on corrosion of mild steel in hydrogen cyanide by adding sodium benzoate in regulated volume was investigated using the fundamental weight loss measurement.500 ppm concentration inhibitive mixtures of sodium benzoate and sodium sulphite in three different volume ratios (5/15, 10/10, 15/5 were formulated and studied for corrosion rate in 200ml hydrogen cyanide fluid. Result obtained indicates that the corrosion rate of mild steel in hydrogen cyanide in the presence of sodium benzoate/sodium sulphite inhibitive mixtures range 0.322mmpy to 1.1269mmpy across the three volumetric ratios considered. The 15ml5ml sodium benzoatesodium sulphite mixture had the best average corrosion rate of 0.5123mmpy.The corrosion rate followed reducing pattern after the first 200 hours of immersion. The average corrosion rate in the sodium benzoate / sodium sulphite mixture is less than the rate in sodium sulphite and the mixture is only effective after long time exposure.It is concluded that adding sodium benzoate to sodium sulphite in the volumetric ratio 155ml improves the inhibitive strength of sodium sulphite on the corrosion of mild steel in hydrogen cyanide environment.

  10. Biodegradation of the anionic surfactant sodium dodecyl sulfate by local bacterial isolate

    International Nuclear Information System (INIS)

    Ibrahim, H.M.M.; NoorEl-Din, M.R.

    2011-01-01

    Anionic surfactants, e.g., sodium dodecyl sulfate (SDS), as a main components in the detergent and cosmetic industries, contribute significantly to the pollution profile of sewage and wastewaters of all kinds. The purpose of this study was to isolate local SDS degrading bacteria. Screening was carried out by the conventional enrichment culture technique. One bacterial isolate was obtained; this isolate was primarily defined as gram-negative rods . It was capable of degrading 100% of 1000 and 2000 mg/l of SDS after 6 days of incubation. The isolate exhibited maximum growth at SDS concentration 4000 mg/I, but it was significantly decreased at higher concentration (16000 mg/I).All the carbon sources being tested repressed the degradation ability. Sodium nitrate at concentration of 2.0 g/I was the best nitrogen source for growth and SDS biodegradation, it enhanced the degradation of 3000 mg/I SDS by 95%,i.e., by 32% upon the control (broth medium containing NH 4 Cl). SDS degradation by the bacterium was optimum at initial ph 8.5, incubation temperature 35 degree C, and inoculum size 2% (v/v). Under the optimized conditions, almost 98% of initial SDS concentration (4000 mg/l) was degraded after 120 h of incubation. Gamma irradiation did not improve the biodegradation ability of this bacterial isolate.

  11. Release of fission products from contaminated sodium fires

    International Nuclear Information System (INIS)

    Jordan, S.

    1976-01-01

    Leaks in the primary coolant system of a LMFBR and also serious incidents with tank rupture may entail the escape of fission products into the containment of the reactor. For incident analysis it is important to know the retention capability of sodium for the different fission products. The release of cesium and strontium from pools contaminated with 100 to 1000 ppM was investigated by experiments. The cesium content of airborne aerosols depends on oxygen concentration: at 21 percent oxygen concentration the Cs content of sodium-oxide aerosols is 3 times and at 0.5 percent 15 times as high as the initial Cs concentration in the pool. Strontium content of aerosols over burning contaminated sodium pools is 10 3 times smaller than the strontium pool concentration

  12. Stabilization of the Serum Lithium Concentration by Regulation of Sodium Chloride Intake: Case Report.

    Science.gov (United States)

    Tomita, Takashi; Goto, Hidekazu; Sumiya, Kenji; Yoshida, Tadashi; Tanaka, Katsuya; Kohda, Yukinao

    2016-01-01

    To avoid fluctuation of the serum lithium concentration (CLi), sodium chloride (NaCl) intake was regulated in oral alimentation. A 62-year-old woman was hospitalized and orally administered 400 mg of lithium carbonate a day to treat her mania. Her CLi was found to be 0.75-0.81 mEq/L. Vomiting made it difficult for the patient to ingest meals orally, and therefore parenteral nutrition with additional oral intake of protein-fortified food was initiated. On day 22, parenteral nutrition was switched to oral alimentation to enable oral intake of food. The total NaCl equivalent amount was decreased to 1.2 g/d, and the CLi increased to 1.15 mEq/L on day 26. Oral alimentation with semi-solid food blended in a mixer was immediately initiated. Although the total NaCl equivalent amount was increased to 4.5-5.0 g/d, her CLi remained high at 1.14-1.17 mEq/L on days 33 and 49, respectively. We investigated oral administration of NaCl (1.8 g/d) on day 52. The total NaCl equivalent amount was increased to 6.3-6.8 g/d, and the CLi decreased to 1.08-0.97 mEq/L on days 63 and 104, respectively. After the start of the orally administered NaCl, her diet was changed to a completely blended diet on day 125. The total NaCl equivalent amount was increased to 9.0-14.5 g/d, and the CLi decreased to 0.53 mEq/L on day 152; therefore, the oral administration of NaCl was discontinued on day 166. The CLi was found to be 0.70-0.85 mEq/L on days 176 and 220.

  13. Limestone-Concentrate-Pellet Roasting in wet Carbon Dioxide

    Institute of Scientific and Technical Information of China (English)

    1990-01-01

    A roast process for treating chalcopyrite concentrate was developed. The investigation of the reaction of limestone-concentrate-pellet in a wet carbon dioxide flow was carried out by means of a thermogravimetric analysis (TGA) to determine at which temperatures the roasting reaction would take place. The thermodynamic calculations on the roast reaction were made by the use of SOLGASMIX-PV program. The TGA curves and thermodynamic calculations indicated that the conversion of chalcopyrite into bornite took place at about 975K, and the conversion of bornite into chalcocite at 1065-1123K. The thermodynamic calculations also showed that the sulfur released was fixed as calcium sulfide within roasted pellets. X-ray diffraction examination identified these phases in products.

  14. Interaction of Celestine Concentrate and Reagent Grade SrSO4 with Oxalate Solutions

    Directory of Open Access Journals (Sweden)

    Abdullah Obut

    2012-12-01

    Full Text Available The interaction of reagent grade strontium sulphate and celestine concentrate with aqueous solutions of oxalic acid, sodiumoxalate and ammonium oxalate for the production of strontium carbonate were investigated for different oxalate compound:SrSO4 moleratios and reaction times using x-ray diffraction analysis and dissolution tests. Under the same experimental conditions, it was foundthat aqueous oxalic acid and sodium oxalate solutions had no or little effect on reagent grade strontium sulphate or celestineconcentrate, but aqueous ammonium oxalate solution converted them into strontium oxalate hydrate. Strontium carbonate was obtainedat conversion ratios of 74.7% for the celestine concentrate and 84.6 % for the reagent grade strontium sulphate by the decompositionof the obtained strontium oxalate hydrate at 600 °C under air atmosphere.

  15. A Comparison of Concentrations of Sodium and Related Nutrients (Potassium, Total Dietary Fiber, Total and Saturated Fat, and Total Sugar) in Private-Label and National Brands of Popular, Sodium-Contributing, Commercially Packaged Foods in the United States.

    Science.gov (United States)

    Ahuja, Jaspreet K C; Pehrsson, Pamela R; Cogswell, Mary

    2017-05-01

    Private-label brands account for about one in four foods sold in US supermarkets. They provide value to consumers due to their low cost. We know of no US studies comparing the nutrition content of private-label products with corresponding national brand products. The objective was to compare concentrations of sodium and related nutrients (potassium, total dietary fiber, total and saturated fat, and total sugar) in popular sodium-contributing, commercially packaged foods by brand type (national or private-label brand). During 2010 to 2014, the Nutrient Data Laboratory of the US Department of Agriculture obtained 1,706 samples of private-label and national brand products from up to 12 locations nationwide and chemically analyzed 937 composites for sodium and related nutrients. The samples came from 61 sodium-contributing, commercially packaged food products for which both private-label and national brands were among the top 75% to 80% of brands for US unit sales. In this post hoc comparative analysis, the authors assigned a variable brand type (national or private label) to each composite and determined mean nutrient contents by brand type overall and by food product and type. The authors tested for significant differences (Pfoods sampled, differences between brand types were not statistically significant for any of the nutrients studied. However, differences in both directions exist for a few individual food products and food categories. Concentrations of sodium and related nutrients (potassium, total dietary fiber, total and saturated fat, and total sugar) do not differ systematically between private-label and national brands, suggesting that brand type is not a consideration for nutritional quality of foods in the United States. The study data provide public health officials with baseline nutrient content by brand type to help focus US sodium-reduction efforts. Published by Elsevier Inc.

  16. Radioimmunoassay of sodium cromoglycate in human plasma

    Energy Technology Data Exchange (ETDEWEB)

    Brown, K; Gardner, J J; Lockley, W J.S.; Preston, J R; Wilkinson, D J [Fisons plc, Loughborough (UK). Pharmaceutical Div.

    1983-01-01

    A sensitive radioimmunoassay method for sodium cromoglycate in human plasma is described. The lowest quantifiable concentration of sodium cromoglycate is 0.93 nmol/l when 0.1 ml plasma samples are analysed. The range of the method is limited; both 0.01 and 0.1 ml volumes of plasma must be analysed to encompass the concentration range 0.93-139 nmol/l which may be encountered in plasma samples from patients and human volunteers. The method is specific for sodium cromoglycate as indicated by a low cross-reactivity of the anti-cromoglycate antiserum with a number of drugs.

  17. The Dissolution of Synthetic Na-Boltwoodite in Sodium Carbonate Solutions

    International Nuclear Information System (INIS)

    Ilton, Eugene S.; Liu, Chongxuan; Yantasee, Wassana; Wang, Zheming; Moore, Dean A.; Felmy, Andrew R.; Zachara, John M.

    2006-01-01

    Uranyl silicates such as uranophane and Na-boltwoodite appear to control the solubility of uranium in the contaminated sediments at the US Department of Energy Hanford site (Liu et al., 2004). Consequently, the solubility of synthetic Na-boltwoodite was determined over a wide range of bicarbonate concentrations, from circumneutral to alkaline pH, that are representative of porewater and groundwater compositions at the Hanford site. Results show that Na-boltwoodite dissolution was nearly congruent and its solubility increased with increasing bicarbonate concentration. Calculated solubility constants varied by nearly 2 log units from low bicarbonate (no added NaCO3) to 50 mmol/L bicarbonate. However, the solubility constants only vary by 0.5 log units from 0 added bicarbonate to 1.2 mmol/L bicarbonate, where logKsp = 5.39-5.92 and the average logKsp = 5.63. No systematic trend in logKsp was apparent over this range in bicarbonate concentrations. LogKsp values trended down with increasing bicarbonate concentration, where logKsp = 4.06 at 50 mmol/L bicarbonate. We conclude that the calculated solubility constants at high bicarbonate are compromised by an incomplete or inaccurate uranyl-carbonate speciation model

  18. One-dimensional coaxial Sb and carbon fibers with enhanced electrochemical performance for sodium-ion batteries

    Science.gov (United States)

    Zhu, Mengnan; Kong, Xiangzhong; Yang, Hulin; Zhu, Ting; Liang, Shuquan; Pan, Anqiang

    2018-01-01

    Antimony (Sb) has been intensively investigated as a promising anode material for sodium ion batteries (SIBs) in recent years. However, bulk Sb particles usually suffer from excessive volume expansion thus leading to dramatic capacity decay after cycling. To address this issue, Sb has been uniformly decorated on Polyacrylonitrile (PAN) derived carbon nanofibers (PCFs) via a simple chemical deposition strategy to form a one-dimensional (1D) core-shell nanostructure of Sb@PCFs. PCFs were first derived from electrospun PAN fibers and treated with subsequent calcination. The PCFs constructed an interwoven carbon network were later employed for Sb deposition, which can effectively alleviate aggregation or further cracking of Sb nanoparticles occurred in electrochemical kinetic process. The as-obtained Sb@PCFs nanocomposites demonstrated excellent cycling stability with good rate performances. This carefully designed core-shell nanostructure of antimony nanoparticles wrapped PCFs are responsible for good electrochemical Na-ion storage. Moreover, the 1D nanostructure manage to pave pathways for fast ions transfer during charge-discharge, which could extra contribute to the enhanced SIBs performances.

  19. Sorption and desorption kinetics of diuron, fluometuron, prometryn and pyrithiobac sodium in soils.

    Science.gov (United States)

    Baskaran, S; Kennedy, I R

    1999-11-01

    The sorption and desorption characteristics of four herbicides (diuron, fluometuron, prometryn and pyrithiobac-sodium) in three different cotton growing soils of Australia was investigated. Kinetics and equilibrium sorption and desorption isotherms were determined using the batch equilibrium technique. Sorption was rapid (> 80% in 2 h) and sorption equilibrium was achieved within a short period of time (ca 4 h) for all herbicides. Sorption isotherms of the four herbicides were described by Freundlich equation with an r2 value > 0.98. The herbicide sorption as measured by the distribution coefficient (Kd) values ranged from 3.24 to 5.71 L/kg for diuron, 0.44 to 1.13 L/kg for fluometuron, 1.78 to 6.04 L/kg for prometryn and 0.22 to 0.59 L/kg for pyrithiobac-sodium. Sorption of herbicides was higher in the Moree soil than in Narrabri and Wee Waa soils. When the Kd values were normalised to organic carbon content of the soils (Koc), it suggested that the affinity of the herbicides to the organic carbon increased in the order: pyrithiobac-sodium diuron. The desorption isotherms were also adequately described by the Freundlich equation. For desorption, all herbicides exhibited hysteresis and the hysteresis was stronger for highly sorbed herbicides (diuron and prometryn) than the weakly sorbed herbicides (fluometuron and pyrithiobac-sodium). Hysteresis was also quantified as the percentage of sorbed herbicides which is not released during the desorption step (omega = [nad/nde - 1] x 100). Soil type and initial concentration had significant effect on omega. The effect of sorption and desorption properties of these four herbicides on the off-site transport to contaminate surface and groundwater are also discussed in this paper.

  20. Stability of i.v. admixture containing metoclopramide, diphenhydramine hydrochloride, and dexamethasone sodium phosphate in 0.9% sodium chloride injection.

    Science.gov (United States)

    Kintzel, Polly E; Zhao, Ting; Wen, Bo; Sun, Duxin

    2014-12-01

    The chemical stability of a sterile admixture containing metoclopramide 1.6 mg/mL, diphenhydramine hydrochloride 2 mg/mL, and dexamethasone sodium phosphate 0.16 mg/mL in 0.9% sodium chloride injection was evaluated. Triplicate samples were prepared and stored at room temperature without light protection for a total of 48 hours. Aliquots from each sample were tested for chemical stability immediately after preparation and at 1, 4, 8, 24, and 48 hours using liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Metoclopramide, diphenhydramine hydrochloride, and dexamethasone sodium phosphate were selectively monitored using multiple-reaction monitoring. Samples were diluted differently for quantitation using three individual LC-MS/MS methods. To determine the drug concentration of the three compounds in the samples, three calibration curves were constructed by plotting the peak area or the peak area ratio versus the concentration of the calibration standards of each tested compound. Apixaban was used as an internal standard. Linearity of the calibration curve was evaluated by the correlation coefficient r(2). Constituents of the admixture of metoclopramide 1.6 mg/mL, diphenhydramine hydrochloride 2 mg/mL, and dexamethasone sodium phosphate 0.16 mg/mL in 0.9% sodium chloride injection retained more than 90% of their initial concentrations over 48 hours of storage at room temperature without protection from light. The observed variability in concentrations of these three compounds was within the limits of assay variability. An i.v. admixture containing metoclopramide 1.6 mg/mL, diphenhydramine hydrochloride 2 mg/mL, and dexamethasone sodium phosphate 0.16 mg/mL in 0.9% sodium chloride injection was chemically stable for 48 hours when stored at room temperature without light protection. Copyright © 2014 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  1. Evaluation of hydrous ferric oxide loaded activated carbon as a granular composite sorbent for radiostrontium

    International Nuclear Information System (INIS)

    Samanta, S.K.

    1997-01-01

    A composite sorbent was prepared in granular form by depositing hydrous ferric oxide inside the pores of activated carbon. The composite sorbent was found to show excellent sorption of radiostrontium in the presence of high sodium concentration under alkaline conditions. (author). 3 refs., 2 figs., 1 tab

  2. Local transport of vertically- and horizontally-emitted sodium oxide aerosols

    International Nuclear Information System (INIS)

    Fields, D.E.; Miller, C.W.; Cooper, A.C.

    1986-01-01

    Liquid-metal cooled breeder reactors are expected to use large quantities of sodium or sodium-potassium alloy, and evaluation of the possible consequences of a liquid-metal fire, henceforth referred to as a sodium fire, is an important consideration. Of particular interest is the sodium aerosol concentration at the air intake ports that are used for reactor cooling, and which might suffer restricted flow under high aerosol concentrations. We have devised and applied a methodology for estimating the concentration of aerosols released vertically and horizontally from building surfaces and monitored at other building surface points. We have used this methodology to make calculations that indicate the time-development of aerosol build-up, and the maximum aerosol concentrations, at air intake ports. Building wake effects, momentum-driven plume rise, and density-driven plume rise are considered

  3. Local transport of vertically and horizontally emitted sodium oxide aerosols

    International Nuclear Information System (INIS)

    Fields, D.E.; Miller, C.W.; Cooper, A.C.

    1986-01-01

    Liquid-metal-cooled breeder reactors are expected to use large quantities of sodium or sodium-potassium alloy, and evaluation of the possible consequences of a liquid-metal fire, henceforth referred to as a sodium fire, is an important consideration. Of particular interest is the sodium aerosol concentration at the air intake ports that are used for reactor cooling, and which might suffer restricted flow under high aerosol concentrations. The authors have devised and applied a methodology for estimating the concentration of aerosols released vertically and horizontally from building surfaces and monitored at other building surface points. This methodology has been used to make calculations that indicate the time development of aerosol buildup, and the maximum aerosol concentration, at air intake ports. Building wake effects, momentum-driven plume rise, and density-driven plume rise are considered

  4. Cesium Isotherm Testing with Spherical Resorcinol-Formaldehyde Resin at High Sodium Concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Russell, Renee L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fiskum, Sandra K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smoot, Margaret R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rinehart, Donald E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-04-01

    Washington River Protection Solutions (WRPS) is developing a Low-Activity Waste Pretreatment System (LAWPS) to provide low-activity waste (LAW) directly to the Hanford Tank Waste Treatment and Immobilization Plant (WTP) Low-Activity Waste Facility for immobilization. The pretreatment that will be conducted on tank waste supernate at the LAWPS facility entails filtration to remove entrained solids and cesium (Cs) ion exchange to remove Cs from the product sent to the WTP. Currently, spherical resorcinol-formaldehyde (sRF) resin (Microbeads AS, Skedsmokorset, Norway) is the Cs ion exchange resin of choice. Most work on Cs ion exchange efficacy in Hanford tank waste has been conducted at nominally 5 M sodium (Na). WRPS is examining the possibility of processing supernatant at high Na concentrations—up to 8 M Na—to maximize processing efficiency through the LAWPS. Minimal Cs ion exchange work has been conducted at 6 M and 8 M Na concentrations..

  5. Dependence of carbon dioxide concentration on microalgal carbon dioxide fixation

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Yeoung Sang; Park, Song Moon [Department of Chemical Engineering, School of Environmental Engineering, Pohang University of Science and Technology, Pohang (Korea); Bolesky, Bohumil [Department of Chemical Engineering, McGill University (Canada)

    1999-10-01

    Batch cultivation of chlorella vulgaris was carried out under various CO{sub 2} concentrations in order to understand and describe mathematically the CO{sub 2} inhibition of microalgal CO{sub 2} fixation. The volumetric CO{sub 2} transfer coefficient from mixture gas to culture medium was estimated from the volumetric O{sub 2} transfer coefficient obtained experimentally. Using this transfer coefficient and aquatic equilibrium relationship between dissolved inorganic carbons, the behavior of dissolved CO{sub 2} was calculated during microalgal culture. When air containing 0.035%(v/v) CO{sub 2} was supplied into microalgal culture, the fixation rate was limited by CO{sub 2} transfer rate. However, the limitation was disappeared by supplying mixture gas containing above 2%(v/v) CO{sub 2} and the dissolved CO{sub 2} concentration was maintained at the saturated value. In the range of CO{sub 2} partial pressure in the flue gases from thermal power sations and steel-making plants, the microalgal CO{sub 2} fixation rate was inhibited. The CO{sub 2} fixation rate was successfully formulated by a new empirical equation as a function of dissolved CO{sub 2} concentration, which could be useful for modeling and simulating the performance of photobioreaction with enriched CO{sub 2}. Also, it was found that the CO{sub 2} inhibition of microalgal CO{sub 2} fixation was reversible and that microalgal CO{sub 2} fixation process could be stable against a shock of unusually high CO{sub 2} concentration. 29 refs., 8 figs.

  6. The role of sodium in the body

    Directory of Open Access Journals (Sweden)

    Munteanu Constantin

    2011-05-01

    Full Text Available Sodium is a metallic element with the symbol Na , in the same group with Li, K, Rb, Cs; is widespread in nature in the form of salts (nitrates, carbonates, chlorides, atomic number 11 and atomic weight 22,9898 . It,s a soft metal, reactive and with a low melting point , with a relative density of 0,97 at 200C (680 F. From the commercial point of view, sodium is the most important of all the alkaline metals. Elemental sodium was first isolated by Humpry Davy in 1807 by passing an electric current through molten sodium hydroxide. Elemental sodium does not occur naturally on earth, because it quickly oxidizes in air and is violently reactive with water, so it must be stored in a non-oxidizing medium, such as liquid hydrocarbon . The free metal is used for some chemical synthesis, analysis, and heat transfer applications .

  7. Effect of carbon dioxide on the rate of iodine vapor absorption by aqueous solution of sodium hydroxide

    International Nuclear Information System (INIS)

    Eguchi, Wataru; Adachi, Motonari; Miyake, Yoshikazu

    1978-01-01

    There is always carbon dioxide in the atmosphere as an impurity. Since this is an acid gas similar to iodine, each absorption rate seems to be affected by the other due to the coexistence of these two. Experiments have been conducted to clarify the absorption rate and absorption mechanism of iodine in the simultaneous absorption of iodine and carbon dioxide. Carbon dioxide coexisting with gas phases as an impurity decreases the absorption rate of iodine in the removal by washing with water of iodine mixed in the air. The first cause of this is that the diffusion coefficient of iodine in gas phase decreases with the carbon dioxide content in the gas phase. The second cause is that coexistent carbon dioxide is an acid gas, dissociates by dissolving into the absorbing solution, increases hydrogen ion concentration together with the formation of negative ions of bicarbonate and carbonate, and reduces hydroxyl ion concentration as a result. It is more important that existence of iodine has a catalytic effect to the rate of basic catalytic hydrolysis of carbon dioxide simultaneously dissolved in water phase, and accelerates this reaction rate. The mechanism of catalytic effect of iodine for the hydrolysis of carbon dioxide can not be clarified in detail only by this experiment, but the simultaneous absorption rate of iodine and carbon dioxide can be explained satisfactorily. (Wakatsuki, Y

  8. Sensor development for in situ detection of concentration polarization and fouling of reverse osmosis membranes

    Science.gov (United States)

    Detrich, Kahlil T.; Goulbourne, Nakhiah C.

    2009-03-01

    The purpose of this research is to evaluate three polymer electroding techniques in developing a novel in situ sensor for an RO system using the electrical response of a thin film composite sensor. Electrical impedance spectroscopy (EIS) was used to measure the sensor response when exposed to sodium chloride solutions with concentrations from 0.1 M to 0.8 M in both single and double bath configurations. An insulated carbon grease sensor was mechanically stable while a composite Direct Assembly Process (DAP) sensor was fragile upon hydration. Scanning electron microscopy results from an impregnation-reduction technique showed gold nanoparticles were deposited most effectively when presoaked in a potassium hydroxide solution and on an uncoated membrane; surface resistances remained too high for sensor implementation. Through thickness carbon grease sensors showed a transient response to changes in concentration, and no meaningful concentration sensitivity was noted for the time scales over which EIS measurements were taken. Surface carbon grease electrodes attached to the polyamide thin film were not sensitive to concentration. The impedance spectra indicated the carbon grease sensor was unable to detect changes in concentration in double bath experiments when implemented with the polyamide surface exposed to salt solutions. DAP sensors lacked a consistent response to changes in concentration too. A reverse double bath experiment with the polysulfone layer exposed to a constant concentration exhibited a transient impedance response similar to through thickness carbon grease sensors in a single bath at constant concentration. These results suggest that the microporous polysulfone layer is responsible for sensor response to concentration.

  9. Preparation of Potassium Dichromate Crystals from the Chromite Concentrate by Microwave Assisted Leaching

    Directory of Open Access Journals (Sweden)

    Hua Liu

    2017-10-01

    Full Text Available In the present investigation, the oxidizing roasting process of chromite with sodium carbonate to prepare potassium dichromate crystals was studied in the microwave field with air, by heating the chromite and sodium carbonate. The chromite and sodium carbonate heated separately at 1000 °C in the microwave oven (frequency: 2.45 GHz; power 1.5 kW in order to study the microwave absorption properties. The dielectric constant and dielectric loss factor of the chromite and sodium carbonate examined. Then, chromite with sodium carbonate taken in (1:2 ratio and heated at 750 °C. Thus obtained samples were characterized using various techniques includes Powder-XRD (XRD, Scanning Electron Microscopy (SEM, and X-ray fluorescence (XRF. The XRD pattern reveals the existence of Fe3O4, Fe2O3, NaAlO2, and Na2CrO4. The iron and aluminum were leached out as Fe2O3 and Al(OH3 respectively. The resulting sample treated with the KCl to prepare potassium dichromate crystals. Finally, potassium dichromate crystals formed.

  10. 40 CFR 141.41 - Special monitoring for sodium.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Special monitoring for sodium. 141.41... and Prohibition on Lead Use § 141.41 Special monitoring for sodium. (a) Suppliers of water for... distribution system for the determination of sodium concentration levels; samples must be collected and...

  11. Chromatographic behavior of carbonate complexes of lanthanides and of thorium in alumina

    International Nuclear Information System (INIS)

    Tomida, E.K.

    1977-01-01

    The chromatographic behavior of some rare earth elements and thorium on alumina is studied in order to evaluate the possibility of separation from concentration of trace rare earths from high-purity thorium compounds. The effect of some factors on complex thorium carbonate formation and the extent of thorium solubility in sodium and potassium carbonate solutions investigated. The sorption of rare earth elements and thoriuum on alumina from alkali carbonate solution is observed, despite the reports that alumina acts as a cation exchanger in alkali media and that thorium and rare earths form stable anionic carbonate complexes. The formation of these elements between alumina and potassium carbonate solutions is studied as a function of pH, carbonate concentration and metal ion concentration. Also the elution of rare earths from alumina is studied and the best results are obtained with mineral acids and EDTA plus alkali carbonate solutions. The effect of some parameters as column aging, mixed solvents, column treatment with organic solvents, temperature, aluant concentration is investigated. Attempting to understand this sorption mechanism, some experiments with strongly basic anion exchanger and cation exchangers of strongly acid and weakly acid type are accomplished. It is observed that there are significant differences, in some conditions, between the behavior of rare earths and of thorium, pointing our the possibility of separation of one lanthanide from others and of these from thorium [pt

  12. An Amorphous Carbon Nitride Composite Derived from ZIF-8 as Anode Material for Sodium-Ion Batteries.

    Science.gov (United States)

    Fan, Jing-Min; Chen, Jia-Jia; Zhang, Qian; Chen, Bin-Bin; Zang, Jun; Zheng, Ming-Sen; Dong, Quan-Feng

    2015-06-08

    An composite comprising amorphous carbon nitride (ACN) and zinc oxide is derived from ZIF-8 by pyrolysis. The composite is a promising anode material for sodium-ion batteries. The nitrogen content of the ACN composite is as high as 20.4 %, and the bonding state of nitrogen is mostly pyridinic, as determined by X-ray photoelectron spectroscopy (XPS). The composite exhibits an excellent Na(+) storage performance with a reversible capacity of 430 mA h g(-1) and 146 mA h g(-1) at current densities of 83 mA g(-1) and 8.33 A g(-1) , respectively. A specific capacity of 175 mA h g(-1) was maintained after 2000 cycles at 1.67 A g(-1) , with only 0.016 % capacity degradation per cycle. Moreover, an accelerating rate calorimetry (ARC) test demonstrates the excellent thermal stability of the composite, with a low self heating rate and high onset temperature (210 °C). These results shows its promise as a candidate material for high-capacity, high-rate anodes for sodium-ion batteries. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Water relations link carbon and oxygen isotope discrimination to phloem sap sugar concentration in eucalyptus globulus

    International Nuclear Information System (INIS)

    Cernusak, L.A.; Farquhar, G.D.; Arthur, D.J; Pate, J.S.

    2002-01-01

    Full text: The carbon isotope ratio of phloem sap sugars has been previously observed to correlate strongly with the phloem sap sugar concentration in Eucalyptus globulus. We hypothesized that the correspondence between these two parameters results from co-linearity in their responses to variation in plant water potential. Carbon isotope discrimination is expected to decrease with decreasing plant water potential due to the influence of stomatal conductance on the ratio of intercellular to ambient CO 2 , concentrations (c 1 /c a ). Conversely, we expected the phloem sap sugar concentration to increase with decreasing plant water potential, thereby maintaining positive turgor pressure within the sieve tubes. The study comprised 40 individual Eucalyptus globulus trees growing in three plantations situated on opposing ends of a rainfall gradient in southwestern Australia. A strong correlation was observed between the carbon isotope ratio in phloem sap sugars and phloem sap sugar concentration. Carbon isotope discrimination correlated positively with shoot water potential, whereas phloem sap sugar concentration correlated negatively with shoot water potential. The relationship between carbon isotope discrimination measured in phloem sap sugars collected from the stem and c 1 /c a measured instantaneously on subtending leaves was close to that theoretically predicted. Accordingly, a strong, negative relationship was observed between instantaneous c 1 /c a and the phloem sap sugar concentration. Oxygen isotope discrimination in phloem sap sugars also correlated strongly with phloem sap sugar concentration. A theoretical model suggested that the observed variation in stomatal conductance was sufficient to account for the variation observed in oxygen isotope discrimination across the study. Results strongly support the contention that water relations form a mechanistic link between phloem sap sugar concentration and both instantaneous and integrated measures of the

  14. Sodium transport through the cerebral sodium-glucose transporter exacerbates neuron damage during cerebral ischaemia.

    Science.gov (United States)

    Yamazaki, Yui; Harada, Shinichi; Wada, Tetsuyuki; Yoshida, Shigeru; Tokuyama, Shogo

    2016-07-01

    We recently demonstrated that the cerebral sodium-glucose transporter (SGLT) is involved in postischaemic hyperglycaemia-induced exacerbation of cerebral ischaemia. However, the associated SGLT-mediated mechanisms remain unclear. Thus, we examined the involvement of cerebral SGLT-induced excessive sodium ion influx in the development of cerebral ischaemic neuronal damage. [Na+]i was estimated according to sodium-binding benzofuran isophthalate fluorescence. In the in vitro study, primary cortical neurons were prepared from fetuses of ddY mice. Primary cortical neurons were cultured for 5 days before each treatment with reagents, and these survival rates were assessed using biochemical assays. In in vivo study, a mouse model of focal ischaemia was generated using middle cerebral artery occlusion (MCAO). In these experiments, treatment with high concentrations of glucose induced increment in [Na+]i, and this phenomenon was suppressed by the SGLT-specific inhibitor phlorizin. SGLT-specific sodium ion influx was induced using a-methyl-D-glucopyranoside (a-MG) treatments, which led to significant concentration-dependent declines in neuronal survival rates and exacerbated hydrogen peroxide-induced neuronal cell death. Moreover, phlorizin ameliorated these effects. Finally, intracerebroventricular administration of a-MG exacerbated the development of neuronal damage induced by MCAO, and these effects were ameliorated by the administration of phlorizin. Hence, excessive influx of sodium ions into neuronal cells through cerebral SGLT may exacerbate the development of cerebral ischaemic neuronal damage. © 2016 Royal Pharmaceutical Society.

  15. Dual energy CT monitoring of the renal corticomedullary sodium gradient in swine

    International Nuclear Information System (INIS)

    Kumar, Rahi; Wang, Zhen J.; Forsythe, Carlos; Fu Yanjun; Chen, Yunn-Yi; Yeh, Benjamin M.

    2012-01-01

    Objective: To evaluate the feasibility of dual-energy CT (DECT) for monitoring dynamic changes in the renal corticomedullary sodium gradient in swine. Material and methods: This study was approved by our Institutional Animal Care and Use Committee. Four water-restricted pigs were CT-scanned at 80 and 140 kVp at baseline and at 5 min intervals for 30 min during saline or furosemide diuresis. The renal cortical and medullary CT numbers were recorded. A DECT basis material decomposition method was used to quantify renal cortical and medullary sodium concentrations and medulla-to-cortex sodium ratios at each time point based on the measured CT numbers. The sodium concentrations and medulla-to-cortex sodium ratios were compared between baseline and at 30 min diuresis using paired Student t-tests. The medulla-to-cortex sodium ratios were considered to reflect the corticomedullary sodium gradient. Results: At baseline prior to saline diuresis, the mean medullary and cortical sodium concentrations were 103.8 ± 8.7 and 65.3 ± 1.7 mmol/l, respectively, corresponding to a medulla-to-cortex sodium ratio of 1.59. At 30 min of saline diuresis, the medullary and cortical sodium concentrations decreased to 72.3 ± 1.0 and 56.0 ± 1.4 mmol/l, respectively, corresponding to a significantly reduced medulla-to-cortex sodium ratio of 1.29 (P < 0.05). At baseline prior to furosemide diuresis, the mean medullary and cortical sodium concentrations were 110.5 ± 3.6 and 66.7 ± 4.1 mmol/l, respectively, corresponding to a medulla-to-cortex sodium ratio of 1.66. At 30 min of furosemide diuresis, the medullary and cortical sodium concentrations decreased to 68.5 ± 0.3 and 58.9 ± 4.0 mmol/l, respectively, corresponding to a significantly reduced medulla-to-cortex sodium ratio of 1.16 (P < 0.05). One of the 4 pigs developed acute tubular necrosis likely related to prolonged hypoxia during intubation prior to the furosemide diuresis experiment. The medulla-to-cortex sodium ratio for this

  16. Glassy carbon electrode modified with multi-walled carbon nanotubes sensor for the quantification of antihistamine drug pheniramine in solubilized systems.

    Science.gov (United States)

    Jain, Rajeev; Sharma, Sanjay

    2012-02-01

    A sensitive electroanalytical method for quantification of pheniramine in pharmaceutical formulation has been investigated on the basis of the enhanced electrochemical response at glassy carbon electrode modified with multi-walled carbon nanotubes in the presence of sodium lauryl sulfate. The experimental results suggest that the pheniramine in anionic surfactant solution exhibits electrocatalytic effect resulting in a marked enhancement of the peak current response. Peak current response is linearly dependent on the concentration of pheniramine in the range 200-1500 μg/mL with correlation coefficient 0.9987. The limit of detection is 58.31 μg/mL. The modified electrode shows good sensitivity and repeatability.

  17. Thermal stability and oxidizing properties of mixed alkaline earth-alkali molten carbonates: A focus on the lithium-sodium carbonate eutectic system with magnesium additions

    International Nuclear Information System (INIS)

    Frangini, Stefano; Scaccia, Silvera

    2013-01-01

    Highlights: • TG/DSC analysis was conducted on magnesium-containing eutectic Li/Na eutectic carbonates. • Magnesium influence on the oxygen solubility properties of carbonate was also experimentally determined at 600 °C and 650 °C. • A reproducible partial decarbonation process in premelting region caused formation of magnesium oxycarbonate-like phases. • The acidobase buffering action of magnesium oxycarbonate species could explain the high basic/oxidizing properties of such carbonate melts. • A general correlation between thermal instability in premelting region and basic/oxidizing melt properties was established. - Abstract: A comparative study on thermal behavior and oxygen solubility properties of eutectic 52/48 lithium/sodium carbonate salt containing minor additions of magnesium up to 10 mol% has been made in order to determine whether a general correlation between these two properties can be found or not. Consecutive TG/DSC heating/cooling thermal cycles carried out under alternating CO 2 and N 2 gas flows allowed to assign thermal events observed in the premelting region to a partial decarbonation process of the magnesium-alkali mixed carbonates. The observed decarbonation process at 460 °C is believed to come from initial stage of thermal decomposition of magnesium carbonate resulting in the metastable formation of magnesium oxycarbonate-like phases MgO·2MgCO 3 , in a similar manner as previously reported for lanthanum. Reversible formation and decomposition of the magnesium carbonate phase has been observed under a CO 2 gas atmosphere. The intensity of the decomposition process shows a maximum for a 3 mol% MgO addition that gives also the highest oxygen solubility, suggesting therefore that instability thermal analysis in the premelting region can be considered as providing an effective measure of the basicity/oxidizing properties of alkali carbonate melts with magnesium or, in more general terms, with cations that are strong modifiers of

  18. Stabilized sulfur as cathodes for room temperature sodium-ion batteries.

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yunhua [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering; Liu, Yang [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Center for Integrated Nanotechnologies; Zhu, Yujie [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering; Zheng, Shiyou [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering; Liu, Yihang [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering; Luo, Chao [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering; Gaskell, Karen [Univ. of Maryland, College Park, MD (United States). Dept. of Chemistry and Biochemistry; Eichhorn, Bryan [Univ. of Maryland, College Park, MD (United States). Dept. of Chemistry and Biochemistry; Wang, Chunsheng [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering

    2013-05-01

    Sodium-sulfur batteries, offering high capacity and low cost, are promising alternative to lithium-ion batteries for large-scale energy storage applications. The conventional sodium-sulfur batteries, operating at a high temperature of 300–350°C in a molten state, could lead to severe safety problems. However, the room temperature sodium-sulfur batteries using common organic liuid electrolytes still face a significant challenge due to the dissolution of intermediate sodium polysulfides. For this study, we developed room temperatue sodium-sulfur batteries using a unique porous carbon/sulfur (C/S) composite cathode, which was synthesized by infusing sulfur vapor into porous carbon sphere particles at a high temperatrure of 600°C. The porous C/S composites delivered a reversible capacity of ~860 mAh/g and retained 83% after 300 cycles. The Coulombic efficiency of as high as 97% was observed over 300 cycles. The superior electrochemical performance is attrbuted to the super sulfur stability as evidenced by its lower sensitivity to probe beam irradiation in TEM, XPS and Raman charaterization and high evaperation temperature in TGA. The results make it promising for large-scale grid energy storage and electric vehicles.

  19. Degradation modes of austenitic and ferritic–martensitic stainless steels in He–CO–CO2 and liquid sodium environments of equivalent oxygen and carbon chemical potentials

    International Nuclear Information System (INIS)

    Gulsoy, G.; Was, G.S.; Pawel, S.J.; Busby, J.T.

    2013-01-01

    The objective of this work is to explore possible thermodynamic correlations between the degradation modes of austenitic and ferritic–martensitic alloys observed in high temperature He–CO–CO 2 environments with oxygen and carbon chemical potentials equivalent to that in a liquid sodium environment containing 2–5 molppm oxygen and 0.02–0.2 molppm carbon at temperatures 500–700 °C. Two He–CO–CO 2 environments (Pco/Pco 2 = 1320, Pco = 1980 molppm, and Pco/Pco 2 = 9, Pco = 13.5 molppm) were selected to test alloys NF616 and 316L at 700 and 850 °C. Upon exposure to He environments at 850 °C, 316L samples exhibited thick surface Cr 2 O 3 scales and substantial internal oxidation; however at 700 °C no significant internal oxidation was observed. NF616 samples exhibited relatively thinner surface Cr 2 O 3 scales compared to 316L samples at both temperatures. NF616 samples exposed to liquid sodium at 700 °C and He–Pco/Pco 2 = 9 at 850 °C showed decarburization. No surface oxide formation was observed on the sample exposed to the Na environment. Results obtained from He exposure experiments provide insight into what may occur during long exposure times in a sodium environment

  20. Preparation and investigation of ion exchange properties of sorbent based on activated carbon BAU and zirconium hydroxide

    International Nuclear Information System (INIS)

    Blokhin, A.A.; Semenov, M.I.; Taushkanov, V.P.; Andronov, E.A.

    1978-01-01

    The method of obtaining the sorbent based on the activated carbon and zirconium hydroxide, performed by carbon soaking by zirconium salt solution, hydrolytic decomposition, being in salt pores by ammonia solution and drying of the obtained sorbet in the air at the temperature of 105-115 deg. The kinetic characteristics of the obtained sorbent in the wide range of pH value of solutions are studied; sodium, chloride, fluoride and phosphate ion sorbtion taken as examples. A high selectivity of the sorbent to phosphate and fluoride ions has been established. The usefullness of the obtained sorbent for extraction of phosphorus microquantities from 1M sodium chloride solution and its concentration at the elution stage is shown

  1. Cleaning of Sodium in the Cold Trap

    International Nuclear Information System (INIS)

    Kim, Byung Ho; Jeong, Ji Young; Kim, Jong Man; Choi, Byung Hae; Nam, Ho Yun

    2005-01-01

    The purpose of a cleaning process is to remove the residual sodium adhering to the component walls once it has been properly drained. It is necessary to clean and decontaminate a component, especially the large components of the primary coolant system; such as the intermediate heat exchangers and the primary pump. Improper and inadequate cleaning has in a number of cases resulted in problems in the storage, handling, and reuse of components. Several types of failures due to improper cleaning procedures have been defined in the past. Inadequate and incomplete removal of sodium results in residues which may contain metallic sodium and alkaline compounds such as sodium hydroxide, sodium oxide, sodium carbonate, and various types of alcoholates. Reinsertion of components containing these compounds into a high-temperature sodium system can result in either the intergranular penetration characteristic of a high- oxygen sodium or an accelerated corrosion due to oxygen. The methods used for cleaning sodium equipment depend on the condition and types of equipment to be cleaned and whether the equipment is to be reused. Cleaning methods are needed that will avoid a deleterious local overheating, material surface degradation or deposits, chemical, physical, or mechanical damage, and external effects. This paper discusses a steam-nitrogen gas cleaning method for the routine applications that permits the reuse of the cold trap in sodium

  2. Effect of Biodiesel Concentration on Corrosion of Carbon Steel by Serratia marcescens

    Directory of Open Access Journals (Sweden)

    Pusparizkita Yustina M

    2018-01-01

    Full Text Available Biodiesel come into being used as an alternative source of energy as the diminishing of petroleum reserves. This fuel is typically stored in tanks that are commonly made from carbon steel, which is easily corroded by microorganisms. Recent studies have shown that bacteria aside from SRB may also be involved in corrosion. Therefore, this research was aimed to evaluate the effect of biodiesel concentration (15%, 20% and 30% v/v mixed in diesel oil on the corrosion of carbon steel by S. marcescens that dominate biocorrosion on hydrocarbon products. In this study, the corrosion process was investigated by evaluation of biofilm morphology and composition, the rate of corrosion and the corrosion product of carbon steel which was exposed in the mixture of hydrocarbons and the presence of S. marcescens. It can be concluded that higher concentration of biodiesel in diesel oil leads to higher growth of bacteria in the biofilm and higher corrosion rate.

  3. Sodium removal by alcohol process: Basic tests and its application

    International Nuclear Information System (INIS)

    Nakai, S.; Yamamoto, S.; Akai, M.; Yatabe, T.

    1997-01-01

    We have various methods for sodium removal; an alcohol cleaning process, a steam cleaning process and a direct burning process. Sodium removal by the alcohol process has a lot of advantages, such as causing no alkali corrosion to steel, short processing time and easy operation. Therefore the alcohol process was selected for the 1MWt double wall tube straight type steam generator. We have already had some experiences of the alcohol process, while still needed to confirm the sodium removal rate in the crevice and to develop an on-line sodium concentration monitoring method in alcohol during sodium removal. We have conducted the small scale sodium removal test with flowing alcohol where the sodium removal rate in the crevice and the alcohol conductivity were measured as functions of sodium concentration in alcohol and alcohol temperature. The sodium removal of the DWTSG was conducted by the devised alcohol process safely and efficiently. The process hour was about 1 day. Visual inspection during dismantling of the DWTSG showed no evidence of any un-reacted sodium. (author)

  4. Radiation-use of a forest exposed to elevated concentrations of atmospheric carbon dioxide

    International Nuclear Information System (INIS)

    DeLucia, E. H.; George, K.; Hamilton, J. G.

    2002-01-01

    Radiation-use efficiency of growth (defined as biomass accumulation per unit of absorbed photosynthetically active radiation) of loblobby pine forest plots exposed to ambient or elevated atmospheric carbon dioxide concentration was compared. Biomass accumulation of the dominant loblobby pines was calculated from monthly measurements of tree growth and site-specific allometric measurements. Leaf area index was estimated by optical, allometric and interfall methods, depending on species. Results showed that depending on tree height, elevated carbon dioxide did not alter the above-ground biomass allocation in loblobby pine. Leaf area index estimates by the different methods were found to vary significantly, but elevated carbon dioxide had only a slight effect on leaf area index in the first three years of this study. The 27 per cent increase in radiation-use efficiency of growth in response to carbon dioxide enrichment is believed to have been caused primarily by the stimulation of biomass increment. It was concluded that long-term increases in atmospheric carbon dioxide concentration can increase the radiation-use efficiency of growth in closed canopy forests, but the magnitude and duration of this increase in uncertain. 57 refs., 2 tabs., 3 figs

  5. Sodium tripolyphosphate cross-linked chitosan based sensor for enhacing sensing properties towards acetone

    Science.gov (United States)

    Nasution, T. I.; Asrosa, R.; Nainggolan, I.; Balyan, M.; Indah, R.; Wahyudi, A.

    2018-02-01

    In this report, sensing properties of sodium tripolyphosphate (TPP) cross-linked chitosan based sensor has been successfully enhanced towards acetone. Chitosan solutions were cross-linked with sodium TPP in variation of 0.1%, 0.5%, 1% and 1.5% w/v, respectively. The sensors were fabricated in film form using an electrochemical deposition method. The sensing properties of the sensors were observed by exposing the pure chitosan and sodium TPP cross-linked chitosan sensors towards acetone concentrations of 5, 10, 50, 100 and 200 ppm. The measurement results revealed that the maximum response in output voltage value of pure chitosan sensor was 0.35 V while sodium TPP crosslinked chitosan sensors were above 0.35 V towards 5 ppm acetone concentration. When the sensors were exposed towards acetone concentration of 200 ppm, the maximum response of pure chitosan was 0.45 V while sodium TPP crosslinked chitosan sensors were above 0.45 V. Amongst the variation of sodium TPP, the maximum response of 1% sodium TPP was the highest since the maximum response was 0.4 V and 0.6 V towards 5 ppm and 200 ppm acetone concentration, respectively. While the maximum responses of other sodium TPP concentrations were under 0.4 V and 0.6 V towards 5 ppm and 200 ppm acetone concentration. Moreover, 1% sodium TPP cross-linked chitosan based sensor showed good reproducibility and outstanding lifetime. Therefore, 1% sodium TPP cross-linked chitosan based sensor has exhibited remarkable sensing properties as a novel acetone sensor.

  6. Effect of the Carbon Concentration, Blend Concentration, and Renewal Rate in the Growth Kinetic of Chlorella sp.

    Directory of Open Access Journals (Sweden)

    Adriano Arruda Henrard

    2014-01-01

    Full Text Available The microalgae cultivation can be used as alternative sources of food, in agriculture, residual water treatment, and biofuels production. Semicontinuous cultivation is little studied but is more cost-effective than the discontinuous (batch cultivation. In the semicontinuous cultivation, the microalga is maintained in better concentration of nutrients and the photoinhibition by excessive cell is reduced. Thus, biomass productivity and biocompounds of interest, such as lipid productivity, may be higher than in batch cultivation. The objective of this study was to examine the influence of blend concentration, medium renewal rate, and concentration of sodium bicarbonate on the growth of Chlorella sp. during semicontinuous cultivation. The cultivation was carried out in Raceway type bioreactors of 6 L, for 40 d at 30°C, 41.6 µmol m−2 s−1, and a 12 h light/dark photoperiod. Maximum specific growth rate (0.149 d−1 and generating biomass (2.89 g L−1 were obtained when the blend concentration was 0.80 g L−1, the medium renewal rate was 40%, and NaHCO3 was 1.60 g L−1. The average productivity (0.091 g L−1 d−1 was achieved with 0.8 g L−1 of blend concentration and NaHCO3 concentration of 1.6 g L−1, independent of the medium renewal rate.

  7. Determination of Concentration Dependent Diffusion Coefficients of Carbon in Expanded Austenite

    DEFF Research Database (Denmark)

    Hummelshøj, Thomas Strabo; Christiansen, Thomas; Somers, Marcel A. J.

    2008-01-01

    Abstract. In the present paper various experimental procedures to experimentally determine the concentration dependent diffusion coefficient of carbon in expanded austenite are evaluated. To this end thermogravimetric carburization was simulated for various experimental conditions and the evaluated...... composition dependent diffusivity of carbon derived from the simulated experiments was compared with the input data. The most promising procedure for an accurate determination is shown to be stepwise gaseous carburizing of thin foils in a gaseous atmosphere; the finer the stepsize, the more accurate...

  8. Chronic activation of plasma renin is log-linearly related to dietary sodium and eliminates natriuresis in response to a pulse change in total body sodium

    DEFF Research Database (Denmark)

    Kjolby, Mads; Bie, Peter

    2008-01-01

    rate, urine flow, plasma potassium, and plasma renin activity did not change. The results indicate that sodium excretion is controlled by neurohumoral mechanisms that are quite resistant to acute changes in plasma volume and colloid osmotic pressure and are not down-regulated within 2 h. With previous......Cl administration increased PV (+6.3-8.9%) and plasma sodium concentration (~2%) and decreased plasma protein concentration (-6.4-8.1%). Plasma ANG II and aldosterone concentrations decreased transiently. Potassium excretion increased substantially. Sodium excretion, arterial blood pressure, glomerular filtration...

  9. Inhibiting pitting corrosion in carbon steel exposed to dilute radioactive waste slurries

    International Nuclear Information System (INIS)

    Zapp, P.E.; Hobbs, D.T.

    1991-01-01

    Dilute caustic high-level radioactive waste slurries can induce pitting corrosion in carbon steel. Cyclic potentiodynamic polarization tests were conducted in simulated and actual waste solutions to determine minimum concentrations of sodium nitrate which inhibit pitting in ASTM A537 class 1 steel exposed to these solutions. Susceptibility to pitting was assessed through microscopic inspection of specimens and inspection of polarization scans. Long-term coupon immersion tests were conducted to verify the nitrite concentrations established by the cyclic potentiodynamic polarization tests. The minimum effective nitrite concentration is expressed as a function of the waste nitrate concentration and temperature

  10. Production and characterization of biodiesel from carbon dioxide concentrating chemolithotrophic bacteria, Serratia sp. ISTD04.

    Science.gov (United States)

    Bharti, Randhir K; Srivastava, Shaili; Thakur, Indu Shekhar

    2014-02-01

    A chemolithotrophic bacterium, Serratia sp. ISTD04, enriched in the chemostat in presence of sodium bicarbonate as sole carbon source was evaluated for potential of carbon dioxide (CO2) sequestration and biofuel production. CO2 sequestration efficiency of the bacterium was determined by enzymatic activity of carbonic anhydrase and ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO). Further, Western blot analysis confirmed presence of RuBisCO. The bacterium produced 0.487 and 0.647mgmg(-1) per unit cell dry weight of hydrocarbons and lipids respectively. The hydrocarbons were within the range of C13-C24 making it equivalent to light oil. GC-MS analysis of lipids produced by the bacterium indicated presence of C15-C20 organic compounds that made it potential source of biodiesel after transesterification. GC-MS, FTIR and NMR spectroscopic characterization of the fatty acid methyl esters revealed the presence of 55% and 45% of unsaturated and saturated organic compounds respectively, thus making it a balanced biodiesel composition. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Neutral sodium/bicarbonate/sulfate hot waters in geothermal systems

    Energy Technology Data Exchange (ETDEWEB)

    Mahon, W.A.J. (Dept. of Industrial and Scientific Research, Wairakei, New Zealand); Klyen, L.E.; Rhode, M.

    1980-03-01

    The least understood thermal water is a near neutral water which contains varying amounts of bicarbonate and sulfate as the major anions, low concentrations of chloride (< 30 ppM) and sodium as the major cation. In the past this water has been referred to as a sodium bicarbonate water but present studies suggest that the quantities of bicarbonate and sulfate in this water type are frequently of the same order. Of particular interest is the distribution and position of the sodium/bicarbonate/sulfate water in the same and different systems. Many hot springs in Indonesia, for example, discharge water of this composition. Present studies indicate that this water type can originate from high temperature reservoirs which form the secondary steam heated part of a normal high temperature geothermal system. The hydrological conditions producing these waters in geothermal systems are investigated and the relationship between the water type and vapor dominated systems is discussed. It is suggested that the major water type occurring in the so called vapor dominated parts of geothermal systems is this water. The water does not simply represent steam condensate, rather it consists essentially of meteoric water which has been steam heated. The water composition results from the interaction of carbon dioxide and hydrogen sulfide with meteoric water and the rocks confining this water in the aquifer.

  12. Randomized, controlled clinical trial of safety and plasma concentrations of diclofenac in healthy neonatal foals after repeated topical application of 1% diclofenac sodium cream.

    Science.gov (United States)

    Barnett, Susan E; Sellon, Debra C; Hines, Melissa T; Seino, Kathy K; Knych, Heather K

    2017-04-01

    OBJECTIVE To determine the plasma pharmacokinetics and safety of 1% diclofenac sodium cream applied topically to neonatal foals every 12 hours for 7 days. ANIMALS Twelve 2- to 14-day old healthy Arabian and Arabian-pony cross neonatal foals. PROCEDURES A 1.27-cm strip of cream containing 7.3 mg of diclofenac sodium (n = 6 foals) or an equivalent amount of placebo cream (6 foals) was applied topically to a 5-cm square of shaved skin over the anterolateral aspect of the left tarsometatarsal region every 12 hours for 7 days. Physical examination, CBC, serum biochemistry, urinalysis, gastric endoscopy, and ultrasonographic examination of the kidneys and right dorsal colon were performed before and after cream application. Venous blood samples were collected at predefined intervals following application of the diclofenac cream, and plasma diclofenac concentrations were determined by liquid chromatography-mass spectrometry. RESULTS No foal developed any adverse effects attributed to diclofenac application, and no significant differences in values of evaluated variables were identified between treatment groups. Plasma diclofenac concentrations peaked rapidly following application of the diclofenac cream, reaching a maximum of diclofenac sodium cream to foals as described appeared safe, and low plasma concentrations of diclofenac suggested minimal systemic absorption. Practitioners may consider use of this medication to treat focal areas of pain and inflammation in neonatal foals.

  13. Filtration experiments of the KNK II primary sodium

    International Nuclear Information System (INIS)

    Stamm, H.H.

    1987-01-01

    The separated particles of the KNK primary sodium are a result of a normal corrosion rate by using ferritic and austenitic steels in sodium. Similar particle distributions and concentrations were found in primary circuits of other breeder plants (EBR-II et al). The experimental results of the particle concentration in the KNK primary sodium were lower than the theoretical calculation. Based on a corrosion rate of 0.5 micron/y for austenitic steels and a corrosion rate of 1.5 mg/square-cm y for a ferritic steel used in KNK as structure material an equilibrium particle concentration of 1.066 mg/kg Na was calculated. The experimental results of particle size are not in agreement with theoretical calculation of the BACCHUS code. (orig.)

  14. Calculation of Sodium Fire Test-I (Run-E6) using sodium combustion analysis code ASSCOPS version 2.0

    Energy Technology Data Exchange (ETDEWEB)

    Nakagiri, Toshio; Ohno, Shuji; Miyake, Osamu [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1997-11-01

    The calculation of Sodium Fire Test-I (Run-E6) was performed using the ASSCOPS (Analysis of Simultaneous Sodium Combustions in Pool and Spray) code version 2.0 in order to determine the parameters used in the code for the calculations of sodium combustion behavior of small or medium scale sodium leak, and to validate the applicability of the code. The parameters used in the code were determined and the validation of the code was confirmed because calculated temperatures, calculated oxygen concentration and other calculated values almost agreed with the test results. (author)

  15. Effect of increased carbon dioxide concentrations on stratospheric ozone

    International Nuclear Information System (INIS)

    Boughner, R.E.

    1978-01-01

    During the past several years, much attention has been focused on the destruction of ozone by anthropogenic pollutants such as the nitrogen oxides and chlorofluoromethane. Little or no attention has been given to the influence on ozone of an increased carbon dioxide concentration for which a measurable growth has been observed. Increased carbon dioxide can directly affect ozone by perturbing atmospheric temperatures, which will alter ozone production, whose rate displays a fairly strong temperature dependence. This paper presents one-dimensional model results for the steady state ozone behavior when the CO 2 concentration is twice its ambient level which account for coupling between chemistry and temperature. When the CO 2 level doubled, the total ozone burden increased in relation to the ambient burden by 1.2--2.5%, depending on the vertical diffusion coefficient used. Above 30 km. In this region the relation variations were insensitive to the choice of diffusion coefficient. Below 30 km, ozone concentrations were smaller than the unperturbed values and were sensitive to the vertical diffusion profile in this region (10--30 km). Ozone decreases in the lower stratosphere because of a reduction in ozone-producing solar radiation, which results in smaller downward ozone fluxes from the region at 25--30 km relative to the flux values for the ambient atmosphere. These offsetting changes occurring in the upper and lower stratosphere act to minimize the variation in total ozone

  16. Concentration of enteric virus indicator from seawater using granular activated carbon.

    Science.gov (United States)

    Cormier, Jiemin; Gutierrez, Miguel; Goodridge, Lawrence; Janes, Marlene

    2014-02-01

    Fecal contamination of shellfish growing seawater with enteric viruses is often associated with human outbreaks of gastroenteritis. Male specific bacteriophage MS2 is correlated with those of enteric viruses in a wide range of water environments and has been used widely as a surrogate for pathogenic waterborne viruses. Since viruses in contaminated water are usually at low levels, the development of methods to concentrate viruses from water is crucial for detection purposes. In the present study, granular activated carbon was evaluated for concentration of MS2 from artificial seawater, and different parameters of the seawater were also compared. Recovery of MS2 from warm seawater (37°C) was found to be significantly greater than from cold seawater (4 and 20°C), and even greater than from fresh water (4, 20 and 37°C); the difference between seawater and fresh water became less profound when the temperatures of both were below 37°C. Although not of statistical significance, recovery of MS2 from low salinity seawater (10 and 20 parts per thousand, ppt) was greater than from high salinity seawater (30 and 40ppt). One gram of granular activated carbon was able to extract 6-log plaque forming units (PFU) of MS2 from 500ml seawater at 37°C. This study demonstrated that granular activated carbon can concentrate an enteric virus indicator from shellfish growing seawater effectively. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Influence of mixing and solid concentration on sodium bicarbonate secondary nucleation rate in stirred tank

    Energy Technology Data Exchange (ETDEWEB)

    Wylock, C.; Debaste, F.; Haut, B. [Transfers, Interfaces and Processes - Chemical Engineering Unit, ULB, Brussels (Belgium); Gutierrez, V.; Delplancke-Ogletree, M.P. [Chemicals and Materials Department, ULB, Brussels (Belgium); Cartage, T. [Solvay SA, Brussels (Belgium)

    2010-09-15

    This work aims to investigate the influence of the solid concentration in suspension on the contact secondary nucleation rate of sodium bicarbonate crystallization in a stirred tank crystallizer and to show the necessity of a local description of the mixing for a nucleation rate influence study. Experiments and computational fluid dynamics (CFD) simulations are realized. Crystallization kinetic parameters are extracted from experimental data using a mass distribution fitting approach. CFD and the experimental results allow identifying that a mixing property correlated with the measurements of the secondary nucleation rate in the stirred tank crystallizer appears to be the turbulent dissipation rate on the edge of the impeller. Its influence and the influence of the solid concentration in the suspension on the secondary nucleation rate are estimated by the evaluation of their exponents in a kinetic law. The obtained exponent values are then discussed qualitatively. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Selective extraction of chromium(VI) using a leaching procedure with sodium carbonate from some plant leaves, soil and sediment samples

    Energy Technology Data Exchange (ETDEWEB)

    Elci, Latif, E-mail: elci@pamukkale.edu.tr [Department of Chemistry, Pamukkale University, 20017 Denizli (Turkey); Divrikli, Umit; Akdogan, Abdullah; Hol, Aysen; Cetin, Ayse [Department of Chemistry, Pamukkale University, 20017 Denizli (Turkey); Soylak, Mustafa [Department of Chemistry, Erciyes University, 38039 Kayseri (Turkey)

    2010-01-15

    Speciation of chromium in some plant leaves, soil and sediment samples was carried out by selective leaching of Cr(VI) using a sodium carbonate leaching procedure. Total chromium from the samples was extracted using aqua regia and oxidative acid digestion, respectively. The concentrations of chromium species in the extracts were determined using by graphite furnace atomic absorption spectrometry (GFAAS). Uncoated graphite furnace tubes were used as an atomizer. Due to the presence of relatively high amounts of Na{sub 2}CO{sub 3} in the resulting samples, the possible influences of Na{sub 2}CO{sub 3} on the absorbance signals were checked. There is no interference of Na{sub 2}CO{sub 3} on the chromium absorbance up to 0.1 mol L{sup -1} Na{sub 2}CO{sub 3}. A limit of detection (LOD) for determination of Cr(VI) in 0.1 Na{sub 2}CO{sub 3} solution by GFAAS was found to be 0.93 {mu}g L{sup -1}. The procedure was applied to environmental samples. The relative standard deviation, R.S.D. as precision for 10 replicate measurements of 20 {mu} L{sup -1} Cr in processed soil sample was 4.2%.

  19. Selective extraction of chromium(VI) using a leaching procedure with sodium carbonate from some plant leaves, soil and sediment samples.

    Science.gov (United States)

    Elci, Latif; Divrikli, Umit; Akdogan, Abdullah; Hol, Aysen; Cetin, Ayse; Soylak, Mustafa

    2010-01-15

    Speciation of chromium in some plant leaves, soil and sediment samples was carried out by selective leaching of Cr(VI) using a sodium carbonate leaching procedure. Total chromium from the samples was extracted using aqua regia and oxidative acid digestion, respectively. The concentrations of chromium species in the extracts were determined using by graphite furnace atomic absorption spectrometry (GFAAS). Uncoated graphite furnace tubes were used as an atomizer. Due to the presence of relatively high amounts of Na(2)CO(3) in the resulting samples, the possible influences of Na(2)CO(3) on the absorbance signals were checked. There is no interference of Na(2)CO(3) on the chromium absorbance up to 0.1 mol L(-1) Na(2)CO(3). A limit of detection (LOD) for determination of Cr(VI) in 0.1 Na(2)CO(3) solution by GFAAS was found to be 0.93 microg L(-1). The procedure was applied to environmental samples. The relative standard deviation, R.S.D. as precision for 10 replicate measurements of 20 microL(-1) Cr in processed soil sample was 4.2%.

  20. Analysis of the sodium concrete interactions with the NABE code

    International Nuclear Information System (INIS)

    Soule, N.

    1989-01-01

    Experimental studies have been performed in France to investigate sodium-concrete interactions: thermal decomposition of concrete, specific chemical reactions, experimentation in liquid and vapour phase, sodium-concrete interaction without liner protection. Simultaneously computer codes have been developed in order to study the response of the containment building of a liquid metal fast breeder reactor to a sodium pool fire worsened by a sodium-concrete interaction: the NABE code. This code takes into account: a) sodium combustion; b) thermal decomposition of concrete with associated chemical reactions: (liquid sodium-vapour water reaction, liquid sodium-carbon dioxide reaction, liquid sodium-solid compounds of concrete, hydrogen combustion); c) chemical reactions in vapour phase; d) decay heat; e) gas aerosol inlets/outlets; f) aerosol behaviour (sedimentation, diffusion, leak); g) thermal exchanges. An example of a situation, typical of assessment of beyond design basis situations in LMFBR, is given. (author)